Sample records for keratan sulfate proteoglycans

  1. Articular chondrocyte metabolism and osteoarthritis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leipold, H.R.

    The three main objectives of this study were: (1) to determine if depletion of proteoglycans from the cartilage matrix that occurs during osteoarthritis causes a measurable increase of cartilage proteoglycan components in the synovial fluid and sera, (2) to observe what effect intracellular cAMP has on the expression of matrix components by chondrocytes, and (3) to determine if freshly isolated chondrocytes contain detectable levels of mRNA for fibronectin. Canine serum keratan sulfate and hyaluronate were measured to determine if there was an elevation of these serum glycosaminoglycans in a canine model of osteoarthritis. A single intra-articular injection of chymopapain intomore » a shoulder joint increased serum keratan sulfate 10 fold and hyaluronate less than 2 fold in 24 hours. Keratan sulfate concentrations in synovial fluids of dogs about one year old were unrelated to the presence of spontaneous cartilage degeneration in the joints. High keratan sulfate in synovial fluids correlated with higher keratan sulfate in serum. The mean keratan sulfate concentration in sera of older dogs with osteoarthritis was 37% higher than disease-free controls, but the difference between the groups was not statistically significant. Treatment of chondrocytes with 0.5 millimolar (mM) dibutyryl cAMP (DBcAMP) caused the cells to adopt a more rounded morphology. There was no difference between the amount of proteins synthesized by cultures treated with DBcAMP and controls. The amount of fibronectin (FN) in the media of DBcAMP treated cultures detected by an ELISA was specifically reduced, and the amount of {sup 35}S-FN purified by gelatin affinity chromatography decreased. Moreover, the percentage of FN containing the extra domain. A sequence was reduced. Concomitant with the decrease in FN there was an increase in the concentration of keratan sulfate.« less

  2. A Better Way to Excise Inhibitory Molecules (CSPGs) from a Spinal Cord Injury Scar to Promote Regeneration

    DTIC Science & Technology

    2012-10-01

    chondroitin sulfate proteoglycans (CSPGs) are elevated in the glial scar and are a major...also  blocks  neural  regeneration.  Inhibitory   chondroitin   sulfate  proteoglycans  (CSPGs)  are  elevated  in  the... chondroitin   sulfate ,  keratan   sulfate ,  and  N-­‐linked  oligosaccharides  (Figure  3).  We  have   observed

  3. Bone sialoprotein keratan sulfate proteoglycan (BSP-KSPG) and FGF-23 are important physiological components of medullary bone.

    PubMed

    Hadley, Jill A; Horvat-Gordon, Maria; Kim, Woo-Kyun; Praul, Craig A; Burns, Dennis; Leach, Roland M

    2016-04-01

    Medullary bone is a specialized bone found in the marrow cavity of laying birds. It provides a significant contribution to the calcium supply for egg shell formation. Medullary bone is distinguished from cortical bone by the presence of large amounts of a keratan sulfate proteoglycan (KSPG). The aims of the present experiment are to confirm the identity of the core protein of KSPG, identify a marker of medullary bone metabolism, and determine whether changes in keratan sulfate (KS) concentration in blood are associated with the egg-laying cycle. Using two different isolation techniques- one specific for bone and another for blood- we have identified bone sialoprotein (BSP) to be the core protein of this KSPG. We also determined that the amount of keratan sulfate (KS) in laying hen blood fluctuates in synchrony with the egg-laying cycle, and thus can serve as a specific marker for medullary bone metabolism. During the course of this investigation, we also found FGF-23 (phosphatonin) to be expressed in medullary bone, in synchrony with the egg-laying cycle. Western blotting was used to demonstrate the presence of this peptide in both laying hen blood and medullary bone extracts. The importance of FGF-23 (phosphatonin) and parathyroid hormone in normalizing the dramatic changes in plasma calcium and phosphorus during the 24h egg-laying cycle is discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Podocalyxin as a major pluripotent marker and novel keratan sulfate proteoglycan in human embryonic and induced pluripotent stem cells.

    PubMed

    Toyoda, Hidenao; Nagai, Yuko; Kojima, Aya; Kinoshita-Toyoda, Akiko

    2017-04-01

    Podocalyxin (PC) was first identified as a heavily sialylated transmembrane protein of glomerular podocytes. Recent studies suggest that PC is a remarkable glycoconjugate that acts as a universal glyco-carrier. The glycoforms of PC are responsible for multiple functions in normal tissue, human cancer cells, human embryonic stem cells (hESCs), and human induced pluripotent stem cells (hiPSCs). PC is employed as a major pluripotent marker of hESCs and hiPSCs. Among the general antibodies for human PC, TRA-1-60 and TRA-1-81 recognize the keratan sulfate (KS)-related structures. Therefore, It is worthwhile to summarize the outstanding chemical characteristic of PC, including the KS-related structures. Here, we review the glycoforms of PC and discuss the potential of PC as a novel KS proteoglycan in undifferentiated hESCs and hiPSCs.

  5. Sequence, molecular properties, and chromosomal mapping of mouse lumican

    NASA Technical Reports Server (NTRS)

    Funderburgh, J. L.; Funderburgh, M. L.; Hevelone, N. D.; Stech, M. E.; Justice, M. J.; Liu, C. Y.; Kao, W. W.; Conrad, G. W.; Spooner, B. S. (Principal Investigator)

    1995-01-01

    PURPOSE. Lumican is a major proteoglycan of vertebrate cornea. This study characterizes mouse lumican, its molecular form, cDNA sequence, and chromosomal localization. METHODS. Lumican sequence was determined from cDNA clones selected from a mouse corneal cDNA expression library using a bovine lumican cDNA probe. Tissue expression and size of lumican mRNA were determined using Northern hybridization. Glycosidase digestion followed by Western blot analysis provided characterization of molecular properties of purified mouse corneal lumican. Chromosomal mapping of the lumican gene (Lcn) used Southern hybridization of a panel of genomic DNAs from an interspecific murine backcross. RESULTS. Mouse lumican is a 338-amino acid protein with high-sequence identity to bovine and chicken lumican proteins. The N-terminus of the lumican protein contains consensus sequences for tyrosine sulfation. A 1.9-kb lumican mRNA is present in cornea and several other tissues. Antibody against bovine lumican reacted with recombinant mouse lumican expressed in Escherichia coli and also detected high molecular weight proteoglycans in extracts of mouse cornea. Keratanase digestion of corneal proteoglycans released lumican protein, demonstrating the presence of sulfated keratan sulfate chains on mouse corneal lumican in vivo. The lumican gene (Lcn) was mapped to the distal region of mouse chromosome 10. The Lcn map site is in the region of a previously identified developmental mutant, eye blebs, affecting corneal morphology. CONCLUSIONS. This study demonstrates sulfated keratan sulfate proteoglycan in mouse cornea and describes the tools (antibodies and cDNA) necessary to investigate the functional role of this important corneal molecule using naturally occurring and induced mutants of the murine lumican gene.

  6. Fibroblast growth factor-2 promotes keratan sulfate proteoglycan expression by keratocytes in vitro

    NASA Technical Reports Server (NTRS)

    Long, C. J.; Roth, M. R.; Tasheva, E. S.; Funderburgh, M.; Smit, R.; Conrad, G. W.; Funderburgh, J. L.

    2000-01-01

    Keratocytes of the corneal stroma produce a specialized extracellular matrix responsible for corneal transparency. Corneal keratan sulfate proteoglycans (KSPG) are unique products of keratocytes that are down-regulated in corneal wounds and in vitro. This study used cultures of primary bovine keratocytes to define factors affecting KSPG expression in vitro. KSPG metabolically labeled with [(35)S]sulfate decreased during the initial 2-4 days of culture in quiescent cultures with low serum concentrations (0.1%). Addition of fetal bovine serum, fibroblast growth factor-2 (FGF-2), transforming growth factor beta, or platelet derived growth factor all stimulated cell division, but only FGF-2 stimulated KSPG secretion. Combined with serum, FGF-2 also prevented serum-induced KSPG down-regulation. KSPG secretion was lost during serial subculture with or without FGF-2. Expression of KSPG core proteins (lumican, mimecan, and keratocan) was stimulated by FGF-2, and steady state mRNA pools for these proteins, particularly keratocan, were significantly increased by FGF-2 treatment. KSPG expression therefore is supported by exogenous FGF-2 and eliminated by subculture of the cells in presence of serum. FGF-2 stimulates KSPG core protein expression primarily through an increase in mRNA pools.

  7. Proteoglycan biosynthesis in chondrocytes: protein A-gold localization of proteoglycan protein core and chondroitin sulfate within Golgi subcompartments

    PubMed Central

    1985-01-01

    The intracellular pathway of cartilage proteoglycan biosynthesis was investigated in isolated chondrocytes using a protein A-gold electron microscopy immunolocalization procedure. Proteoglycans contain a protein core to which chondroitin sulfate and keratan sulfate chains and oligosaccharides are added in posttranslational processing. Specific antibodies have been used in this study to determine separately the distribution of the protein core and chondroitin sulfate components. In normal chondrocytes, proteoglycan protein core was readily localized only in smooth-membraned vesicles which co-labeled with ricin, indicating them to be galactose-rich medial/trans-Golgi cisternae, whereas there was only a low level of labeling in the rough endoplasmic reticulum. Chondroitin sulfate was also localized in medial/trans-Golgi cisternae of control chondrocytes but was not detected in other cellular compartments. In cells treated with monensin (up to 1.0 microM), which strongly inhibits proteoglycan secretion (Burditt, L.J., A. Ratcliffe, P. R. Fryer, and T. Hardingham, 1985, Biochim. Biophys. Acta., 844:247-255), there was greatly increased intracellular localization of proteoglycan protein core in both ricin- positive vesicles, and in ricin-negative vesicles (derived from cis- Golgi stacks) and in the distended rough endoplasmic reticulum. Chondroitin sulfate also increased in abundance after monensin treatment, but continued to be localized only in ricin-positive vesicles. The results suggested that the synthesis of chondroitin sulfate on proteoglycan only occurs in medial/trans-Golgi cisternae as a late event in proteoglycan biosynthesis. This also suggests that glycosaminoglycan synthesis on proteoglycans takes place in a compartment in common with events in the biosynthesis of both O-linked and N-linked oligosaccharides on other secretory glycoproteins. PMID:3934179

  8. Bone Matrix Proteins: Isolation and Characterization of a Novel Cell-binding Keratan Sulfate Proteoglycan (Osteoadherin) from Bovine Bone

    PubMed Central

    Wendel, Mikael; Sommarin, Yngve; Heinegård, Dick

    1998-01-01

    A small cell-binding proteoglycan for which we propose the name osteoadherin was extracted from bovine bone with guanidine hydrochloride–containing EDTA. It was purified to homogeneity using a combination of ion-exchange chromatography, hydroxyapatite chromatography, and gel filtration. The Mr of the proteoglycan was 85,000 as determined by SDS-PAGE. The protein is rich in aspartic acid, glutamic acid, and leucine. Two internal octapeptides from the proteoglycan contained the sequences Glu-Ile-Asn-Leu-Ser-His-Asn-Lys and Arg-Asp-Leu-Tyr-Phe-Asn-Lys-Ile. These sequences are not previously described, and support the notion that osteoadherin belongs to the family of leucine-rich repeat proteins. A monospecific antiserum was raised in rabbits. An enzyme-linked immunosorbent assay was developed, and showed the osteoadherin content of bone extracts to be 0.4 mg/g of tissue wet weight, whereas none was found in extracts of various other bovine tissues. Metabolic labeling of primary bovine osteoblasts followed by immunoprecipitation showed the cells to synthesize and secrete the proteoglycan. Digesting the immunoprecipitated osteoadherin with N-glycosidase reduced its apparent size to 47 kD, thus showing the presence of several N-linked oligosaccharides. Digestion with keratanase indicated some of the oligosaccharides to be extended to keratan sulfate chains. In immunohistochemical studies of the bovine fetal rib growth plate, osteoadherin was exclusively identified in the primary bone spongiosa. Osteoadherin binds to hydroxyapatite. A potential function of this proteoglycan is to bind cells, since we showed it to be as efficient as fibronectin in promoting osteoblast attachment in vitro. The binding appears to be mediated by the integrin αvβ3, since this was the only integrin isolated by osteoadherin affinity chromatography of surface-iodinated osteoblast extracts. PMID:9566981

  9. Contaminants in commercial preparations of ‘purified’ small leucine-rich proteoglycans may distort mechanistic studies

    PubMed Central

    Brown, Sharon J.; Fuller, Heidi R.; Jones, Philip; Caterson, Bruce; Shirran, Sally L.; Botting, Catherine H.

    2016-01-01

    The present study reports the perplexing results that came about because of seriously impure commercially available reagents. Commercial reagents and chemicals are routinely ordered by scientists and expected to have been rigorously assessed for their purity. Unfortunately, we found this assumption to be risky. Extensive work was carried out within our laboratory using commercially sourced preparations of the small leucine-rich proteoglycans (SLRPs), decorin and biglycan, to investigate their influence on nerve cell growth. Unusual results compelled us to analyse the composition and purity of both preparations of these proteoglycans (PGs) using both mass spectrometry (MS) and Western blotting, with and without various enzymatic deglycosylations. Commercial ‘decorin’ and ‘biglycan’ were found to contain a mixture of PGs including not only both decorin and biglycan but also fibromodulin and aggrecan. The unexpected effects of ‘decorin’ and ‘biglycan’ on nerve cell growth could be explained by these impurities. Decorin and biglycan contain either chondroitin or dermatan sulfate glycosaminoglycan (GAG) chains whereas fibromodulin only contains keratan sulfate and the large (>2500 kDa), highly glycosylated aggrecan contains both keratan and chondroitin sulfate. The different structure, molecular weight and composition of these impurities significantly affected our work and any conclusions that could be made. These findings beg the question as to whether scientists need to verify the purity of each commercially obtained reagent used in their experiments. The implications of these findings are vast, since the effects of these impurities may already have led to inaccurate conclusions and reports in the literature with concomitant loss of researchers’ funds and time. PMID:27994047

  10. Studies on the asparagine-linked oligosaccharides from cartilage-specific proteoglycan

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cioffi, L.C.

    1987-01-01

    Chondrocytes synthesize and secrete a cartilage-specific proteoglycan (PG-H) as one of their major products. This proteoglycan has attached to it several types of carbohydrate chains, including chondroitin sulfate, keratan sulfate, O-linked oligosaccharides, and asparagine-linked oligosaccharides. The asparagine-linked oligosaccharides found on PG-H were investigated in these studies. Methodology was developed for the isolation and separation of standard of standard complex and high mannose type oligosaccharides. This included digesting glycoproteins with N-glycanase and separation of the oligosaccharides according to type by concanavalin-A lectin chromatography. The different oligosaccharide types were then analyzed by high pressure liquid chromatography. This methodology was used in themore » subsequent studies on the PG-H asparagine-linked oligosaccharides. Initially, the asparagine-linked oligosaccharides recovered from the culture medium (CM) and cell-associated (Ma) fractions of PG-H from of tibial chondrocytes were labeled with (/sup 3/H)-mannose and the oligosaccharides were isolated and analyzed.« less

  11. A multi-analytical approach to better assess the keratan sulfate contamination in animal origin chondroitin sulfate.

    PubMed

    Restaino, Odile Francesca; Finamore, Rosario; Diana, Paola; Marseglia, Mariacarmela; Vitiello, Mario; Casillo, Angela; Bedini, Emiliano; Parrilli, Michelangelo; Corsaro, Maria Michela; Trifuoggi, Marco; De Rosa, Mario; Schiraldi, Chiara

    2017-03-15

    Chondroitin sulfate is a glycosaminoglycan widely used as active principle of anti-osteoarthritis drugs and nutraceuticals, manufactured by extraction from animal cartilaginous tissues. During the manufacturing procedures, another glycosaminoglycan, the keratan sulfate, might be contemporarily withdrawn, thus eventually constituting a contaminant difficult to be determined because of its structural similarity. Considering the strict regulatory rules on the pureness of pharmaceutical grade chondrotin sulfate there is an urgent need and interest to determine the residual keratan sulfate with specific, sensitive and reliable methods. To pursue this aim, in this paper, for the first time, we set up a multi-analytical and preparative approach based on: i) a newly developed method by high performance anion-exchange chromatography with pulsed amperometric detection, ii) gas chromatography-mass spectrometry analyses, iii) size exclusion chromatography analyses coupled with triple detector array module and on iv) strong anion exchange chromatography separation. Varied KS percentages, in the range from 0.1 to 19.0% (w/w), were determined in seven pharmacopeia and commercial standards and nine commercial samples of different animal origin and manufacturers. Strong anion exchange chromatography profiles of the samples showed three or four different peaks. These peaks analyzed by high performance anion-exchange with pulsed amperometric detection and size exclusion chromatography with triple detector array, ion chromatography and by mono- or two-dimensional nuclear magnetic resonance revealed a heterogeneous composition of both glycosaminoglycans in terms of sulfation grade and molecular weight. High molecular weight species (>100 KDa) were also present in the samples that counted for chains still partially linked to a proteoglycan core. Copyright © 2016 The Author(s). Published by Elsevier B.V. All rights reserved.

  12. EDTA-insoluble, calcium-binding proteoglycan in bovine bone

    NASA Technical Reports Server (NTRS)

    Hashimoto, Y.; Lester, G. E.; Caterson, B.; Yamauchi, M.

    1995-01-01

    A calcium ion precipitable, trypsin-generated proteoglycan fragment has been isolated from the demineralized, EDTA-insoluble matrices of bone. The demineralized matrix was completely digested with trypsin, increasing concentrations of CaCl2 were added to the supernatant, and the resulting precipitates were analyzed. The amount of precipitate gradually increased with higher concentrations of calcium and was reversibly solubilized by EDTA. After molecular sieve and anion exchange chromatography, a proteoglycan-containing peak was obtained. Immunochemical analysis showed that this peak contained chondroitin 4-sulfate and possibly keratan sulfate. Amino acid analysis showed that this proteoglycan contained high amounts of aspartic acid/asparagine (Asx), serine (Ser), glutamic acid/glutamine (Glx), proline (Pro), and glycine (Gly); however, it contained little leucine (Leu) which suggests that it is not a member of the leucine-rich small proteoglycan family. In addition, significant amounts of phosphoserine (P-Ser) and hydroxyproline (Hyp) were identified in hydrolysates of this fraction. A single band (M(r) 59 kDa) was obtained on SDS-PAGE that stained with Stains-all but not with Coomassie Brilliant Blue R-250. If bone powder was trypsinized prior to demineralization, this proteoglycan-containing fraction was not liberated. Collectively, these results indicate that a proteoglycan occurs in the demineralized matrix that is precipitated with CaCl2 and is closely associated with both mineral and collagen matrices. Such a molecule might facilitate the structural network for the induction of mineralization in bone.

  13. Deciphering functional glycosaminoglycan motifs in development.

    PubMed

    Townley, Robert A; Bülow, Hannes E

    2018-03-23

    Glycosaminoglycans (GAGs) such as heparan sulfate, chondroitin/dermatan sulfate, and keratan sulfate are linear glycans, which when attached to protein backbones form proteoglycans. GAGs are essential components of the extracellular space in metazoans. Extensive modifications of the glycans such as sulfation, deacetylation and epimerization create structural GAG motifs. These motifs regulate protein-protein interactions and are thereby repsonsible for many of the essential functions of GAGs. This review focusses on recent genetic approaches to characterize GAG motifs and their function in defined signaling pathways during development. We discuss a coding approach for GAGs that would enable computational analyses of GAG sequences such as alignments and the computation of position weight matrices to describe GAG motifs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Sequence and structural implications of a bovine corneal keratan sulfate proteoglycan core protein. Protein 37B represents bovine lumican and proteins 37A and 25 are unique

    NASA Technical Reports Server (NTRS)

    Funderburgh, J. L.; Funderburgh, M. L.; Brown, S. J.; Vergnes, J. P.; Hassell, J. R.; Mann, M. M.; Conrad, G. W.; Spooner, B. S. (Principal Investigator)

    1993-01-01

    Amino acid sequence from tryptic peptides of three different bovine corneal keratan sulfate proteoglycan (KSPG) core proteins (designated 37A, 37B, and 25) showed similarities to the sequence of a chicken KSPG core protein lumican. Bovine lumican cDNA was isolated from a bovine corneal expression library by screening with chicken lumican cDNA. The bovine cDNA codes for a 342-amino acid protein, M(r) 38,712, containing amino acid sequences identified in the 37B KSPG core protein. The bovine lumican is 68% identical to chicken lumican, with an 83% identity excluding the N-terminal 40 amino acids. Location of 6 cysteine and 4 consensus N-glycosylation sites in the bovine sequence were identical to those in chicken lumican. Bovine lumican had about 50% identity to bovine fibromodulin and 20% identity to bovine decorin and biglycan. About two-thirds of the lumican protein consists of a series of 10 amino acid leucine-rich repeats that occur in regions of calculated high beta-hydrophobic moment, suggesting that the leucine-rich repeats contribute to beta-sheet formation in these proteins. Sequences obtained from 37A and 25 core proteins were absent in bovine lumican, thus predicting a unique primary structure and separate mRNA for each of the three bovine KSPG core proteins.

  15. Biochemical properties of a keratan sulphate/chondroitin sulphate proteoglycan expressed in primate pluripotent stem cells*

    PubMed Central

    Cooper, Susan; Bennett, William; Andrade, Jessica; Reubinoff, Benjamin E; Thomson, James; Pera, Martin F

    2002-01-01

    We previously identified a pericellular matrix keratan sulphate/chondroitin sulphate proteoglycan present on the surface of human embryonal carcinoma stem cells, cells whose differentiation mimics early development. Antibodies reactive with various epitopes on this molecule define a cluster of differentiation markers for primate pluripotent stem cells. We describe the purification of a form of this molecule which is secreted or shed into the culture medium. Biochemical analysis of the secreted form of this molecule shows that the monomeric form, whilst containing keratan sulphate, resembles mucins in its structure and its modification with O-linked carbohydrate. Immunofluorescence and immunoblotting data show that monkey and human pluripotent stem cells react with antibodies directed against epitopes on either carbohydrate side chains or the protein core of the molecule. PMID:12033730

  16. Purification of Keratan Sulfate-endogalactosidase and its action on keratan sulfates of different origin.

    PubMed

    Nakazawa, K; Suzuki, S

    1975-02-10

    A glycosidase which attacks corneal keratan sulfate was purified from extracts of Pseudomonas sp. IFO-13309. When corneal keratan sulfate was degraded by the purified enzyme, Sephadex G-50 chromatography indicated the presence of a number of oligosaccharides differing in size and sulfate content. The characterization of two major fractions of the oligosaccharides indicated that the point of enzyme attack is limited to the endo-beta-D-galactoside bonds in which nonsulfated D-galactose residues participate. The enzyme, unlike ordinary exo-beta-D-galactosidases, did not catalyze the hydrolysis of phenyl beta-D-galactoside. Moreover, beta-D-galactosyl-(1 leads to 3)-2-acetamido-2-deoxy-beta-D-glucosyl-(1 leads to 3)-beta-D-galactosyl-(1 leads to 4)-D-glucose ("lacto-N-tetraose") was completely refractory to the action of this enzyme, suggesting that a structure of the type, X-(1 leads to 3)-beta-D-galactosyl-(1 leads to 4)-Y, is not the only specificity-determining factor, i.e. neighboring sugars, X and Y, or even larger portions of substrate molecule must have an important effect. Compared with corneal keratan sulfate, keratan sulfates from human nucleus pulposus and shark cartilage were attacked at lower rates with a resultant production of oligosaccharides of relatively large size. The result is in agreement with the view that considerable variations exist in the structure of keratan sulfates of different origin, and further suggests that the enzyme may serve as a useful reagent in studying these variations.

  17. Expression of Glycosaminoglycan Epitopes During Zebrafish Skeletogenesis

    PubMed Central

    Hayes, Anthony J; Mitchell, Ruth E; Bashford, Andrew; Reynolds, Scott; Caterson, Bruce; Hammond, Chrissy L

    2013-01-01

    Background: The zebrafish is an important developmental model. Surprisingly, there are few studies that describe the glycosaminoglycan composition of its extracellular matrix during skeletogenesis. Glycosaminoglycans on proteoglycans contribute to the material properties of musculo skeletal connective tissues, and are important in regulating signalling events during morphogenesis. Sulfation motifs within the chain structure of glycosaminoglycans on cell-associated and extracellular matrix proteoglycans allow them to bind and regulate the sequestration/presentation of bioactive signalling molecules important in musculo-skeletal development. Results: We describe the spatio-temporal expression of different glycosaminoglycan moieties during zebrafish skeletogenesis with antibodies recognising (1) native sulfation motifs within chondroitin and keratan sulfate chains, and (2) enzyme-generated neoepitope sequences within the chain structure of chondroitin sulfate (i.e., 0-, 4-, and 6-sulfated isoforms) and heparan sulfate glycosaminoglycans. We show that all the glycosaminoglycan moieties investigated are expressed within the developing skeletal tissues of larval zebrafish. However, subtle changes in their patterns of spatio-temporal expression over the period examined suggest that their expression is tightly and dynamically controlled during development. Conclusions: The subtle differences observed in the domains of expression between different glycosaminoglycan moieties suggest differences in their functional roles during establishment of the primitive analogues of the skeleton. Developmental Dynamics 242:778–789, 2013. © 2013 Wiley Periodicals, Inc. Key Findings The developing zebrafish skeleton expresses many different glycosaminoglycan modifications. Multiple different glycosaminoglycan epitopes are dynamically expressed in the craniofacial skeleton. Expression of chondroitin sulfate moieties are dynamically expressed in the vertebral column and precede mineralisation. PMID:23576310

  18. Chondroitin sulfate and keratan sulfate are the major glycosaminoglycans present in the adult zebrafish Danio rerio (Chordata-Cyprinidae).

    PubMed

    Souza, Aline R C; Kozlowski, Eliene O; Cerqueira, Vinicius R; Castelo-Branco, Morgana T L; Costa, Manoel L; Pavão, Mauro S G

    2007-12-01

    The zebrafish Danio rerio (Chordata-Cyprinidae) is a model organism frequently used to study the functions of proteoglycans and their glycosaminoglycan (GAG) chains. Although several studies clearly demonstrate the participation of these polymers in different biological and cellular events that take place during embryonic development, little is known about the GAGs in adult zebrafish. In the present study, the total GAGs were extracted from the whole fish by proteolytic digestion, purified by anion-exchange chromatography and characterized by electrophoresis after degradation with specific enzymes and/or by high-performance liquid chromatography (HPLC) analysis of the disaccharides. Two GAGs were identified: a low-molecular-weight chondroitin sulfate (CS) and keratan sulfate (KS), corresponding to approximately 80% and 20% of the total GAGs, respectively. In the fish eye, KS represents approximately 80% of total GAGs. Surprisingly, no heparinoid was detected, but may be present in the fish at concentrations lower than the limit of the method used. HPLC of the disaccharides formed after chondroitin AC or ABC lyase degradation revealed that the zebrafish CS is composed by DeltaUA-1-->3-GalNAc(4SO4) (59.4%), DeltaUA-1-->3-GalNAc(6SO4) (23.1%), and DeltaUA-1-->3-GalNAc (17.5%) disaccharide units. No disulfated disaccharides were detected. Immunolocalization on sections from zebrafish retina using monoclonal antibodies against CS4- or 6-sulfate showed that in the retina these GAGs are restricted to the outer and inner plexiform layers. This is the first report showing the presence of KS in zebrafish eye, and the structural characterization of CS and its localization in the zebrafish retina. Detailed information about the structure and tissue localization of GAGs is important to understand the functions of these polymers in this model organism.

  19. Heterogeneity in macular corneal dystrophy.

    PubMed

    Edward, D P; Yue, B Y; Sugar, J; Thonar, E J; SunderRaj, N; Stock, E L; Tso, M O

    1988-11-01

    Macular corneal dystrophy is an autosomal recessive disorder in which abnormal deposits in the corneal stroma have been identified. We examined the corneal buttons of 12 patients, who had clinical features of macular dystrophy, by histochemical staining, transmission electron microscopy, and immunohistochemical techniques. All corneas exhibited positive staining with Muller Mowry's colloidal iron. Using monoclonal antibodies 1/20/5-D-4, J-10, J-19, and J-36 that recognize specific sites on the sulfated keratan sulfate molecule, we stained corneal sections by an avidin-biotin-peroxidase complex method and identified two groups of macular corneal dystrophy. One group consisting of four corneas reacted positively with all four antibodies, and the other group consisting of eight corneas did not react with any of the antibodies used. These results confirmed those recently presented by Yang et al that there may be subgroups of macular dystrophy that can be identified by immunohistochemical methods. Also, serum levels of sulfated keratan sulfate were determined in seven patients. One patient who displayed a normal level of serum keratan sulfate had positive corneal immunoreactivity. Of the six patients who lacked serum keratan sulfate, four showed negative and two had positive corneal immunostaining, suggesting at least three subgroups in the disease. An attempt was made to correlate the clinical features, histochemical-staining characteristics, and ultrastructural morphology with the immunoreactivity to keratan sulfate antibodies, but no correlations could be made.

  20. CELLULAR DIFFERENTIATION AND THE AGING PROCESS IN CARTILAGINOUS TISSUES

    PubMed Central

    Shulman, Herbert J.; Meyer, Karl

    1968-01-01

    Primary cell cultures of differentiated chondrocytes were shown to produce chondroitin-4-sulfate as the predominant mucopolysaccharide, with suggestive evidence for the synthesis of keratan sulfate and possibly chondroitin-6-sulfate. Chicken embryonic cartilage was shown to be composed mainly of chondroitin-4-sulfate, with a small amount of chondroitin-6-sulfate, but essentially no keratan sulfate. These findings were compared to the data of others, and a hypothesis explaining the aging process in cartilage in terms of cellular differentiation was presented. PMID:5688079

  1. Serum and synovial fluid concentrations of keratan sulfate and hyaluronan in dogs with induced stifle joint osteoarthritis following cranial cruciate ligament transection.

    PubMed

    Budsberg, Steven C; Lenz, Mary Ellen; Thonar, Eugene J-M A

    2006-03-01

    To examine longitudinal changes in serum and synovial fluid concentrations of keratan sulfate (KS) and hyaluronan (HA) after cranial cruciate ligament (CCL) transection in dogs. 12 clinically normal adult mixed-breed dogs. Following CCL transection in the right stifle joint, KS and HA concentrations were determined in serum and neat (undiluted) synovial fluid prior to and 1, 2, 3, and 12 months after surgery. Postsurgical dilution of synovial fluid was corrected by use of urea as a passive marker. Synovial fluid KS and HA concentrations decreased at 1, 2, and 3 months after surgery in operated stifle joints, compared with baseline values. Synovial fluid KS concentration decreased in unoperated stifle joints at 1 month. A decrease in synovial fluid KS concentration was found in operated stifle joints, compared with unoperated stifle joints, at 2 and 3 months, and a decrease in synovial fluid HA concentrations was also found in operated stifle joints, compared with unoperated stifle joints, at 1, 2, and 3 months. Serum KS concentrations increased from baseline values at 3 months after surgery. Hyaluronan concentrations in operated stifle joints were lower than baseline values at 1, 2, and 3 months. Urea-adjusted synovial fluid concentrations revealed that dilution did not account for the decline in biomarker concentrations. The initial decrease and subsequent increase in synovial fluid concentrations of HA and KS may be caused by an acute inflammatory response to surgical intervention that negatively affects cartilage metabolism or an increase in production of immature proteoglycans.

  2. Biosynthesis of glycosaminoglycans: associated disorders and biochemical tests.

    PubMed

    Sasarman, Florin; Maftei, Catalina; Campeau, Philippe M; Brunel-Guitton, Catherine; Mitchell, Grant A; Allard, Pierre

    2016-03-01

    Glycosaminoglycans (GAG) are long, unbranched heteropolymers with repeating disaccharide units that make up the carbohydrate moiety of proteoglycans. Six distinct classes of GAGs are recognized. Their synthesis follows one of three biosynthetic pathways, depending on the type of oligosaccharide linker they contain. Chondroitin sulfate, dermatan sulfate, heparan sulfate, and heparin sulfate contain a common tetrasaccharide linker that is O-linked to specific serine residues in core proteins. Keratan sulfate can contain three different linkers, either N-linked to asparagine or O-linked to serine/threonine residues in core proteins. Finally, hyaluronic acid does not contain a linker and is not covalently attached to a core protein. Most inborn errors of GAG biosynthesis are reported in small numbers of patients. To date, in 20 diseases, convincing evidence for pathogenicity has been presented for mutations in a total of 16 genes encoding glycosyltransferases, sulfotransferases, epimerases or transporters. GAG synthesis defects should be suspected in patients with a combination of characteristic clinical features in more than one connective tissue compartment: bone and cartilage (short long bones with or without scoliosis), ligaments (joint laxity/dislocations), and subepithelial (skin, sclerae). Some produce distinct clinical syndromes. The commonest laboratory tests used for this group of diseases are analysis of GAGs, enzyme assays, and molecular testing. In principle, GAG analysis has potential as a general first-line diagnostic test for GAG biosynthesis disorders.

  3. Proteoglycans synthesized by smooth muscle cells derived from monkey (Macaca nemestrina) aorta.

    PubMed

    Chang, Y; Yanagishita, M; Hascall, V C; Wight, T N

    1983-05-10

    Smooth muscle cells derived from monkey aorta were cultured in medium with [35S]sulfate and [3H]glucosamine as labeling precursors. Proteoglycans in the medium and in 4 M guanidine HCl extracts of the cell layer were purified by DEAE-Sephacel and molecular sieve chromatography. Both preparations contained a predominant, large chondroitin sulfate proteoglycan (Kav = 0.30 on Sepharose CL-2B) with glycosaminoglycan chains of Mr approximately 43,000 average containing a ratio of 6-sulfate to 4-sulfate of approximately 2. Approximately 7 and 27% of the 3H label in this proteoglycan were present in N-linked and O-linked oligosaccharides, respectively. Reaggregation experiments indicated that a large proportion of these proteoglycans can form link protein-stabilized aggregates. The medium fraction also contained a smaller dermatan sulfate proteoglycan (Kav = 0.67 on Sepharose CL-2B) with glycosaminoglycan chains of Mr approximately 43,000 containing a ratio of 6-sulfate to 4-sulfate of about 0.5. This proteoglycan contained approximately the same percentage of N-linked oligosaccharides as the chondroitin sulfate proteoglycan, but few or no O-linked oligosaccharides. A smaller dermatan sulfate proteoglycan with a single chain was present only in the cell layer. Additionally, small amounts of heparan sulfate proteoglycans were synthesized by the cells.

  4. Quantitative analysis of glycosaminoglycans, chondroitin/dermatan sulfate, hyaluronic acid, heparan sulfate, and keratan sulfate by liquid chromatography-electrospray ionization-tandem mass spectrometry.

    PubMed

    Osago, Harumi; Shibata, Tomoko; Hara, Nobumasa; Kuwata, Suguru; Kono, Michihaya; Uchio, Yuji; Tsuchiya, Mikako

    2014-12-15

    We developed a method using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) with a selected reaction monitoring (SRM) mode for simultaneous quantitative analysis of glycosaminoglycans (GAGs). Using one-shot analysis with our MS/MS method, we demonstrated the simultaneous quantification of a total of 23 variously sulfated disaccharides of four GAG classes (8 chondroitin/dermatan sulfates, 1 hyaluronic acid, 12 heparan sulfates, and 2 keratan sulfates) with a sensitivity of less than 0.5 pmol within 20 min. We showed the differences in the composition of GAG classes and the sulfation patterns between porcine articular cartilage and yellow ligament. In addition to the internal disaccharides described above, some saccharides derived from the nonreducing terminal were detected simultaneously. The simultaneous quantification of both internal and nonreducing terminal saccharides could be useful to estimate the chain length of GAGs. This method would help to establish comprehensive "GAGomic" analysis of biological tissues. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Proteoglycan: collagen interactions in connective tissues. Ultrastructural, biochemical, functional and evolutionary aspects.

    PubMed

    Scott, J E

    1991-06-01

    Electron histochemical investigations of mammalian and echinoderm tissues, using cupromeronic blue to stain proteoglycans (PGs) specifically in critical electrolyte concentration methods, showed that collagen fibrils are associated with keratan sulphate and chondroitin (dermatan) sulphate ('tadpole') PGs at the a, c, d and e bands on the fibril surface, giving rise to the 'one proteoglycan: one binding site' hypothesis. Intra-fibrillar PGs have been observed, distributed in a regular way which suggests that collagen fibrils are aggregates of 'protofibrils', some of which carry PGs at their surfaces. A scheme for remodelling of collagen fibrils, based on recycling of these protofibrils, is outlined. The choice of which tadpole PG to use to carry out a given function is decided to a considerable extent by the availability of oxygen to the relevant tissue element.

  6. Mapping the Differential Distribution of Glycosaminoglycans in the Adult Human Retina, Choroid, and Sclera

    PubMed Central

    Clark, Simon J.; Keenan, Tiarnan D. L.; Fielder, Helen L.; Collinson, Lisa J.; Holley, Rebecca J.; Merry, Catherine L. R.; van Kuppevelt, Toin H.; Day, Anthony J.; Bishop, Paul N.

    2011-01-01

    Purpose. To map the distribution of different classes of glycosaminoglycans (GAGs) in the healthy human retina, choroid, and sclera. Methods. Frozen tissue sections were made from adult human donor eyes. The GAG chains of proteoglycans (PGs) were detected with antibodies directed against various GAG structures (either directly or after pretreatment with GAG-degrading enzymes); hyaluronan (HA) was detected using biotinylated recombinant G1-domain of human versican. The primary detection reagents were identified with FITC-labeled probes and analyzed by fluorescence microscopy. Results. Heparan sulfate (HS), chondroitin sulfate (CS), dermatan sulfate (DS), and HA were present throughout the retina and choroid, but keratan sulfate (KS) was detected only in the sclera. HS labeling was particularly strong in basement membrane–containing structures, the nerve fiber layer (NFL), and retinal pigment epithelium (RPE)—for example, intense staining was seen with an antibody that binds strongly to sequences containing 3-O-sulfation in the internal limiting membrane (ILM) and in the basement membrane of blood vessels. Unsulfated CS was seen throughout the retina, particularly in the ILM and interphotoreceptor matrix (IPM) with 6-O-sulfated CS also prominent in the IPM. There was labeling for DS throughout the retina and choroid, especially in the NFL, ganglion cell layer, and blood vessels. Conclusions. The detection of GAG chains with specific probes and fluorescence microscopy provides for the first time a detailed analysis of their compartmentalization in the human retina, by both GAG chain type and sulfation pattern. This reference map provides a basis for understanding the functional regulation of GAG-binding proteins in health and disease processes. PMID:21746802

  7. Allelic heterogeneity of the carbohydrate sulfotransferase-6 gene in patients with macular corneal dystrophy.

    PubMed

    Sultana, A; Sridhar, M S; Klintworth, G K; Balasubramanian, D; Kannabiran, C

    2005-11-01

    Allelic heterogeneity of the carbohydrate sulfotransferase-6 gene in patients with macular corneal dystrophy. Macular corneal dystrophy (MCD) is an autosomal recessive disorder characterized by grayish white opacities in the cornea. It is caused by mutations in the carbohydrate sulfotransferase-6 (CHST6) gene, which codes for the enzyme corneal N-acetylglucosamine-6-sulfotransferase. This enzyme catalyzes the sulfation of keratan sulfate, an important component of corneal proteoglycans. We screened 31 patients from 26 families with MCD for mutations in the coding region of the CHST6 gene. Twenty-six different mutations were identified, of which 14 mutations are novel. The novel mutations are one nonsense mutation found in one patient (Trp2Ter), one frameshift (insertion plus deletion) mutation in two patients (His335fs), and 12 missense mutations (Leu3Met, Ser54Phe, Val56Arg, Ala73Thr, Ser98Leu, Cys165Trp, Ser167Phe, Phe178Cys, Leu193Pro, Pro204Arg, Arg272Ser, and Arg334Cys) in 11 patients. These data demonstrate a high degree of allelic heterogeneity of the CHST6 gene in patient populations with MCD from Southern India, where this disease may have a relatively higher prevalence than in outbred communities.

  8. Histopathologic and immunohistochemical features of capsular tissue around failed Ahmed glaucoma valves.

    PubMed

    Mahale, Alka; Fikri, Fatma; Al Hati, Khitam; Al Shahwan, Sami; Al Jadaan, Ibrahim; Al Katan, Hind; Khandekar, Rajiv; Maktabi, Azza; Edward, Deepak P

    2017-01-01

    Impervious encapsulation around Ahmed glaucoma valve (AGV) results in surgical failure raising intraocular pressure (IOP). Dysregulation of extracellular matrix (ECM) molecules and cellular factors might contribute to increased hydraulic resistance to aqueous drainage. Therefore, we examined these molecules in failed AGV capsular tissue. Immunostaining for ECM molecules (collagen I, collagen III, decorin, lumican, chondroitin sulfate, aggrecan and keratan sulfate) and cellular factors (αSMA and TGFβ) was performed on excised capsules from failed AGVs and control tenon's tissue. Staining intensity of ECM molecules was assessed using Image J. Cellular factors were assessed based on positive cell counts. Histopathologically two distinct layers were visible in capsules. The inner layer (proximal to the AGV) showed significant decrease in most ECM molecules compared to outer layer. Furthermore, collagen III (p = 0.004), decorin (p = 0.02), lumican (p = 0.01) and chondroitin sulfate (p = 0.02) was significantly less in inner layer compared to tenon's tissue. Outer layer labelling however was similar to control tenon's for most ECM molecules. Significantly increased cellular expression of αSMA (p = 0.02) and TGFβ (p = 0.008) was detected within capsular tissue compared to controls. Our results suggest profibrotic activity indicated by increased αSMA and TGFβ expression and decreased expression of proteoglycan (decorin and lumican) and glycosaminoglycans (chondroitin sulfate). Additionally, we observed decreased collagen III which might reflect increased myofibroblast contractility when coupled with increased TGFβ and αSMA expression. Together these events lead to tissue dysfunction potentially resulting in hydraulic resistance that may affect aqueous flow through the capsular wall.

  9. Effects of high glucose on the production of heparan sulfate proteoglycan by mesangial and epithelial cells.

    PubMed

    van Det, N F; van den Born, J; Tamsma, J T; Verhagen, N A; Berden, J H; Bruijn, J A; Daha, M R; van der Woude, F J

    1996-04-01

    Changes in heparan sulfate metabolism may be important in the pathogenesis of diabetic nephropathy. Recent studies performed on renal biopsies from patients with diabetic nephropathy revealed a decrease in heparan sulfate glycosaminoglycan staining in the glomerular basement membrane without changes in staining for heparan sulfate proteoglycan-core protein. To understand this phenomenon at the cellular level, we investigated the effect of high glucose conditions on the synthesis of heparan sulfate proteoglycan by glomerular cells in vitro. Human adult mesangial and glomerular visceral epithelial cells were cultured under normal (5 mM) and high glucose (25 mM) conditions. Immunofluorescence performed on cells cultured in 25 mM glucose confirmed and extended the in vivo histological observations. Using metabolic labeling we observed an altered proteoglycan production under high glucose conditions, with predominantly a decrease in heparan sulfate compared to dermatan sulfate or chondroitin sulfate proteoglycan. N-sulfation analysis of heparan sulfate proteoglycan produced under high glucose conditions revealed less di- and tetrasaccharides compared to larger oligosaccharides, indicating an altered sulfation pattern. Furthermore, with quantification of glomerular basement membrane heparan sulfate by ELISA, a significant decrease was observed when mesangial and visceral epithelial cells were cultured in high glucose conditions. We conclude that high glucose concentration induces a significant alteration of heparan sulfate production by mesangial cells and visceral epithelial cells. Changes in sulfation and changes in absolute quantities are both observed and may explain the earlier in vivo observations. These changes may be of importance for the altered integrity of the glomerular charge-dependent filtration barrier and growth-factor matrix interactions in diabetic nephropathy.

  10. Proteoglycans and neuronal migration in the cerebral cortex during development and disease

    PubMed Central

    Maeda, Nobuaki

    2015-01-01

    Chondroitin sulfate proteoglycans and heparan sulfate proteoglycans are major constituents of the extracellular matrix and the cell surface in the brain. Proteoglycans bind with many proteins including growth factors, chemokines, axon guidance molecules, and cell adhesion molecules through both the glycosaminoglycan and the core protein portions. The functions of proteoglycans are flexibly regulated due to the structural variability of glycosaminoglycans, which are generated by multiple glycosaminoglycan synthesis and modifying enzymes. Neuronal cell surface proteoglycans such as PTPζ, neuroglycan C and syndecan-3 function as direct receptors for heparin-binding growth factors that induce neuronal migration. The lectican family, secreted chondroitin sulfate proteoglycans, forms large aggregates with hyaluronic acid and tenascins, in which many signaling molecules and enzymes including matrix proteases are preserved. In the developing cerebrum, secreted chondroitin sulfate proteoglycans such as neurocan, versican and phosphacan are richly expressed in the areas that are strategically important for neuronal migration such as the striatum, marginal zone, subplate and subventricular zone in the neocortex. These proteoglycans may anchor various attractive and/or repulsive cues, regulating the migration routes of inhibitory neurons. Recent studies demonstrated that the genes encoding proteoglycan core proteins and glycosaminoglycan synthesis and modifying enzymes are associated with various psychiatric and intellectual disorders, which may be related to the defects of neuronal migration. PMID:25852466

  11. Embryonic lung morphogenesis in organ culture: experimental evidence for a proteoglycan function in the extracellular matrix

    NASA Technical Reports Server (NTRS)

    Spooner, B. S.; Bassett, K. E.; Spooner, B. S. Jr

    1993-01-01

    The lung rudiment, isolated from mid-gestation (11 day) mouse embryos, can undergo morphogenesis in organ culture. Observation of living rudiments, in culture, reveals both growth and ongoing bronchiolar branching activity. To detect proteoglycan (PG) biosynthesis, and deposition in the extracellular matrix, rudiments were metabolically labeled with radioactive sulfate, then fixed, embedded, sectioned and processed for autoradiography. The sulfated glycosaminoglycan (GAG) types, composing the carbohydrate component of the proteoglycans, were evaluated by selective GAG degradative approaches that showed chondroitin sulfate PG principally associated with the interstitial matrix, and heparan sulfate PG principally associated with the basement membrane. Experiments using the proteoglycan biosynthesis disrupter, beta-xyloside, suggest that when chondroitin sulfate PG deposition into the ECM is perturbed, branching morphogenesis is compromised.

  12. Reduced Sulfation of Chondroitin Sulfate but Not Heparan Sulfate in Kidneys of Diabetic db/db Mice

    PubMed Central

    Reine, Trine M.; Grøndahl, Frøy; Jenssen, Trond G.; Hadler-Olsen, Elin; Prydz, Kristian

    2013-01-01

    Heparan sulfate proteoglycans are hypothesized to contribute to the filtration barrier in kidney glomeruli and the glycocalyx of endothelial cells. To investigate potential changes in proteoglycans in diabetic kidney, we isolated glycosaminoglycans from kidney cortex from healthy db/+ and diabetic db/db mice. Disaccharide analysis of chondroitin sulfate revealed a significant decrease in the 4-O-sulfated disaccharides (D0a4) from 65% to 40%, whereas 6-O-sulfated disaccharides (D0a6) were reduced from 11% to 6%, with a corresponding increase in unsulfated disaccharides. In contrast, no structural differences were observed in heparan sulfate. Furthermore, no difference was found in the molar amount of glycosaminoglycans, or in the ratio of hyaluronan/heparan sulfate/chondroitin sulfate. Immunohistochemical staining for the heparan sulfate proteoglycan perlecan was similar in both types of material but reduced staining of 4-O-sulfated chondroitin and dermatan was observed in kidney sections from diabetic mice. In support of this, using qRT-PCR, a 53.5% decrease in the expression level of Chst-11 (chondroitin 4-O sulfotransferase) was demonstrated in diabetic kidney. These results suggest that changes in the sulfation of chondroitin need to be addressed in future studies on proteoglycans and kidney function in diabetes. PMID:23757342

  13. Reduced sulfation of chondroitin sulfate but not heparan sulfate in kidneys of diabetic db/db mice.

    PubMed

    Reine, Trine M; Grøndahl, Frøy; Jenssen, Trond G; Hadler-Olsen, Elin; Prydz, Kristian; Kolset, Svein O

    2013-08-01

    Heparan sulfate proteoglycans are hypothesized to contribute to the filtration barrier in kidney glomeruli and the glycocalyx of endothelial cells. To investigate potential changes in proteoglycans in diabetic kidney, we isolated glycosaminoglycans from kidney cortex from healthy db/+ and diabetic db/db mice. Disaccharide analysis of chondroitin sulfate revealed a significant decrease in the 4-O-sulfated disaccharides (D0a4) from 65% to 40%, whereas 6-O-sulfated disaccharides (D0a6) were reduced from 11% to 6%, with a corresponding increase in unsulfated disaccharides. In contrast, no structural differences were observed in heparan sulfate. Furthermore, no difference was found in the molar amount of glycosaminoglycans, or in the ratio of hyaluronan/heparan sulfate/chondroitin sulfate. Immunohistochemical staining for the heparan sulfate proteoglycan perlecan was similar in both types of material but reduced staining of 4-O-sulfated chondroitin and dermatan was observed in kidney sections from diabetic mice. In support of this, using qRT-PCR, a 53.5% decrease in the expression level of Chst-11 (chondroitin 4-O sulfotransferase) was demonstrated in diabetic kidney. These results suggest that changes in the sulfation of chondroitin need to be addressed in future studies on proteoglycans and kidney function in diabetes.

  14. Targeting Common but Complex Proteoglycans on Breast Cancer Cells and Stem Cells Using Evolutionary Refined Malaria Proteins

    DTIC Science & Technology

    2014-09-01

    chondroitin sulfate A proteoglycans present on all tested breast cancer cells and the vast majority of tested tissue biopsies. Using pull down assays...Invited, Daugaard. C) 2014. Gordon research conference, July 6-11; Targeting of cancer-specific chondroitin sulfate on circulating tumor cells using...now successfully identified a number of proteoglycans that interact with the recombinant malaria protein VAR2CSA when sulfated on carbon 4 of the CS

  15. Molecular Determinants Fundamental to Axon Regeneration after SCI

    DTIC Science & Technology

    2014-09-01

    mammalian spinal cord, axon regeneration is frustrated by inhibitors such as chondroitin sulfate proteoglycans (CSPGs) expressed by reactive astrocytes... chondroitin sulfates . Publications, Abstracts and Presentations: Publications: 1. Katerina Vajn, Jeffery A Plunkett, Alexis Tapanes...Jeffery A. Plunkett. Axonal growth of primary zebrafish brainstem neurons across inhibitory chondroitin sulfate proteoglycans. Manuscript in

  16. Release of chromaffin granule glycoproteins and proteoglycans from potassium-stimulated PC12 pheochromocytoma cells.

    PubMed

    Salton, S R; Margolis, R U; Margolis, R K

    1983-10-01

    Cultured PC12 pheochromocytoma cells were labeled with [3H]glucosamine, and the glycoproteins and proteoglycans released following potassium-induced depolarization were fractionated and characterized. Exposure of PC12 cells for 20 min to a high concentration of potassium (51.5 mM in Krebs-Ringers-HEPES buffer) results in an approximately sixfold increase in the release of labeled glycoproteins and proteoglycans, compared to incubation in physiological levels of potassium (6 mM). The released complex carbohydrates include chromogranins, dopamine beta-hydroxylase, and two chondroitin sulfate/heparan sulfate proteoglycan fractions, which together account for 7.4% of the soluble cell radioactivity. The chromogranins contained galactosyl(beta 1 leads to 3)N-acetylgalactosamine, as well as several mono- and disialyl O-glycosidically-linked oligosaccharides, and the tetrasaccharide AcNeu(alpha 2 leads to 3)Gal(beta 1 leads to 3)[AcNeu(alpha 2 leads to 6)] GalNAcol, obtained by alkaline borohydride treatment of the chromogranin glycopeptides, accounted for almost half of the total chromogranin labeling. The proteoglycan fractions varied in their relative proportions of chondroitin sulfate (23-68%), heparan sulfate (16-23%), and glycoprotein oligosaccharides (16-54%), which are of the tri- and tetraantennary and O-glycosidic types. As previously found in the case of proteoglycans from bovine chromaffin granules, the more acidic species has a considerably higher proportion of carbohydrate in the form of sulfated glycosaminoglycans.

  17. In vivo contribution of amino acid sulfur to cartilage proteoglycan sulfation

    PubMed Central

    Pecora, Fabio; Gualeni, Benedetta; Forlino, Antonella; Superti-Furga, Andrea; Tenni, Ruggero; Cetta, Giuseppe; Rossi, Antonio

    2006-01-01

    Cytoplasmic sulfate for sulfation reactions may be derived either from extracellular fluids or from catabolism of sulfur-containing amino acids and other thiols. In vitro studies have pointed out the potential relevance of sulfur-containing amino acids as sources for sulfation when extracellular sulfate concentration is low or when its transport is impaired such as in DTDST [DTD (diastrophic dysplasia) sulfate transporter] chondrodysplasias. In the present study, we have considered the contribution of cysteine and cysteine derivatives to in vivo macromolecular sulfation of cartilage by using the mouse model of DTD we have recently generated [Forlino, Piazza, Tiveron, Della Torre, Tatangelo, Bonafe, Gualeni, Romano, Pecora, Superti-Furga et al. (2005) Hum. Mol. Genet. 14, 859–871]. By intraperitoneal injection of [35S]cysteine in wild-type and mutant mice and determination of the specific activity of the chondroitin 4-sulfated disaccharide in cartilage, we demonstrated that the pathway by which sulfate is recruited from the intracellular oxidation of thiols is active in vivo. To check whether cysteine derivatives play a role, sulfation of cartilage proteoglycans was measured after treatment for 1 week of newborn mutant and wild-type mice with hypodermic NAC (N-acetyl-L-cysteine). The relative amount of sulfated disaccharides increased in mutant mice treated with NAC compared with the placebo group, indicating an increase in proteoglycan sulfation due to NAC catabolism, although pharmacokinetic studies demonstrated that the drug was rapidly removed from the bloodstream. In conclusion, cysteine contribution to cartilage proteoglycan sulfation in vivo is minimal under physiological conditions even if extracellular sulfate availability is low; however, the contribution of thiols to sulfation becomes significant by increasing their plasma concentration. PMID:16719839

  18. Effects of glucosamine on proteoglycan loss by tendon, ligament and joint capsule explant cultures.

    PubMed

    Ilic, M Z; Martinac, B; Samiric, T; Handley, C J

    2008-12-01

    To investigate the effect of glucosamine on the loss of newly synthesized radiolabeled large and small proteoglycans by bovine tendon, ligament and joint capsule. The kinetics of loss of (35)S-labeled large and small proteoglycans from explant cultures of tendon, ligament and joint capsule treated with 10mM glucosamine was investigated over a 10-day culture period. The kinetics of loss of (35)S-labeled small proteoglycans and the formation of free [(35)S]sulfate were determined for the last 10 days of a 15-day culture period. The proteoglycan core proteins were analyzed by gel electrophoresis followed by fluorography. The metabolism of tendon, ligament and joint capsule explants exposed to 10mM glucosamine was evaluated by incorporation of [(3)H]serine and [(35)S]sulfate into protein and glycosaminoglycans, respectively. Glucosamine at 10mM stimulated the loss of small proteoglycans from ligament explant cultures. This was due to the increased loss of both macromolecular and free [(35)S]sulfate to the medium indicating that glucosamine affected the release of small proteoglycans as well as their intracellular degradation. The degradation pattern of small proteoglycans in ligament was not affected by glucosamine. In contrast, glucosamine did not have an effect on the loss of large or small proteoglycans from tendon and joint capsule or large proteoglycans from ligament explant cultures. The metabolism of cells in tendon, ligament and joint capsule was not impaired by the presence of 10mM glucosamine. Glucosamine stimulated the loss of small proteoglycans from ligament but did not have an effect on small proteoglycan catabolism in joint capsule and tendon or large proteoglycan catabolism in ligament, tendon or synovial capsule. The consequences of glucosamine therapy at clinically relevant concentrations on proteoglycan catabolism in joint fibrous connective tissues need to be further assessed in an animal model.

  19. Decorin and biglycan of normal and pathologic human corneas

    NASA Technical Reports Server (NTRS)

    Funderburgh, J. L.; Hevelone, N. D.; Roth, M. R.; Funderburgh, M. L.; Rodrigues, M. R.; Nirankari, V. S.; Conrad, G. W.

    1998-01-01

    PURPOSE: Corneas with scars and certain chronic pathologic conditions contain highly sulfated dermatan sulfate, but little is known of the core proteins that carry these atypical glycosaminoglycans. In this study the proteoglycan proteins attached to dermatan sulfate in normal and pathologic human corneas were examined to identify primary genes involved in the pathobiology of corneal scarring. METHODS: Proteoglycans from human corneas with chronic edema, bullous keratopathy, and keratoconus and from normal corneas were analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), quantitative immunoblotting, and immunohistology with peptide antibodies to decorin and biglycan. RESULTS: Proteoglycans from pathologic corneas exhibit increased size heterogeneity and binding of the cationic dye alcian blue compared with those in normal corneas. Decorin and biglycan extracted from normal and diseased corneas exhibited similar molecular size distribution patterns. In approximately half of the pathologic corneas, the level of biglycan was elevated an average of seven times above normal, and decorin was elevated approximately three times above normal. The increases were associated with highly charged molecular forms of decorin and biglycan, indicating modification of the proteins with dermatan sulfate chains of increased sulfation. Immunostaining of corneal sections showed an abnormal stromal localization of biglycan in pathologic corneas. CONCLUSIONS: The increased dermatan sulfate associated with chronic corneal pathologic conditions results from stromal accumulation of decorin and particularly of biglycan in the affected corneas. These proteins bear dermatan sulfate chains with increased sulfation compared with normal stromal proteoglycans.

  20. Targeting Common but Complex Proteoglycans on Breast Cancer Cells and Stem Cells Using Evolutionary Refined Malaria Proteins

    DTIC Science & Technology

    2014-09-01

    protein VAR2CSA. We have extensive data demonstrating that this protein specifically targets sulfated chondroitin sulfate A proteoglycans present on all... chondroitin sulfate A on circulating tumor cells using a evolutionary refined malaria protein B) National Annual PhD meeting in Oncology, March 26-27...malaria protein VAR2CSA when sulfated on carbon 4 of the CS backbone. We have identified CSPG4 as a major protein in breast cancer cells, but also a

  1. RNA-Seq identifies SPGs as a ventral skeletal patterning cue in sea urchins.

    PubMed

    Piacentino, Michael L; Zuch, Daniel T; Fishman, Julie; Rose, Sviatlana; Speranza, Emily E; Li, Christy; Yu, Jia; Chung, Oliver; Ramachandran, Janani; Ferrell, Patrick; Patel, Vijeta; Reyna, Arlene; Hameeduddin, Hajerah; Chaves, James; Hewitt, Finnegan B; Bardot, Evan; Lee, David; Core, Amanda B; Hogan, John D; Keenan, Jessica L; Luo, Lingqi; Coulombe-Huntington, Jasmin; Blute, Todd A; Oleinik, Ekaterina; Ibn-Salem, Jonas; Poustka, Albert J; Bradham, Cynthia A

    2016-02-15

    The sea urchin larval skeleton offers a simple model for formation of developmental patterns. The calcium carbonate skeleton is secreted by primary mesenchyme cells (PMCs) in response to largely unknown patterning cues expressed by the ectoderm. To discover novel ectodermal cues, we performed an unbiased RNA-Seq-based screen and functionally tested candidates; we thereby identified several novel skeletal patterning cues. Among these, we show that SLC26a2/7 is a ventrally expressed sulfate transporter that promotes a ventral accumulation of sulfated proteoglycans, which is required for ventral PMC positioning and skeletal patterning. We show that the effects of SLC perturbation are mimicked by manipulation of either external sulfate levels or proteoglycan sulfation. These results identify novel skeletal patterning genes and demonstrate that ventral proteoglycan sulfation serves as a positional cue for sea urchin skeletal patterning. © 2016. Published by The Company of Biologists Ltd.

  2. Mucopolysaccharide and Protein—Polysaccharide of a Transplantable Rat Chondrosarcoma

    PubMed Central

    Choi, Haing Ug; Meyer, Karl; Swarm, Richard

    1971-01-01

    Two mucopolysaccharides, chondroitin 4-sulfate (97.8%) and hyaluronic acid (1.2%), were isolated after exhaustive proteolysis of a transplantable chondrosarcoma of the rat. The chondroitin 4-sulfate was fractionated into three fractions of varying degrees of sulfation and chain length. Keratan sulfate and chondroitin 6-sulfate were absent. Extraction of the fresh tumor gave two protein—polysaccharides of similar carbohydrate composition, one soluble in 0.5 M NaCl, the other insoluble. The latter was solubilized in 4 M guanidine·HCl. A dialyzable fraction from the 4 M guanidine solution may be responsible for the insolubility. Both protein—polysaccharides were antigenic and cross-reacted with similar fractions of bovine and human cartilage. PMID:4252539

  3. Mast Cells Produce a Unique Chondroitin Sulfate Epitope.

    PubMed

    Farrugia, Brooke L; Whitelock, John M; O'Grady, Robert; Caterson, Bruce; Lord, Megan S

    2016-02-01

    The granules of mast cells contain a myriad of mediators that are stored and protected by the sulfated glycosaminoglycan (GAG) chains that decorate proteoglycans. Whereas heparin is the GAG predominantly associated with mast cells, mast cell proteoglycans are also decorated with heparan sulfate and chondroitin sulfate (CS). This study investigated a unique CS structure produced by mast cells that was detected with the antibody clone 2B6 in the absence of chondroitinase ABC digestion. Mast cells in rodent tissue sections were characterized using toluidine blue, Leder stain and the presence of mast cell tryptase. The novel CS epitope was identified in rodent tissue sections and localized to cells that were morphologically similar to cells chemically identified as mast cells. The rodent mast cell-like line RBL-2H3 was also shown to express the novel CS epitope. This epitope co-localized with multiple CS proteoglycans in both rodent tissue and RBL-2H3 cultured cells. These findings suggest that the novel CS epitope that decorates mast cell proteoglycans may play a role in the way these chains are structured in mast cells. © 2016 The Histochemical Society.

  4. Shotgun Proteomic Analysis of Plasma from Dairy Cattle Suffering from Footrot: Characterization of Potential Disease-Associated Factors

    PubMed Central

    Sun, Dongbo; Zhang, Hong; Guo, Donghua; Sun, Anguo; Wang, Hongbin

    2013-01-01

    The plasma proteome of healthy dairy cattle and those with footrot was investigated using a shotgun LC-MS/MS approach. In total, 648 proteins were identified in healthy plasma samples, of which 234 were non-redundant proteins and 123 were high-confidence proteins; 712 proteins were identified from footrot plasma samples, of which 272 were non-redundant proteins and 138 were high-confidence proteins. The high-confidence proteins showed significant differences between healthy and footrot plasma samples in molecular weight, isoelectric points and the Gene Ontology categories. 22 proteins were found that may differentiate between the two sets of plasma proteins, of which 16 potential differential expression (PDE) proteins from footrot plasma involved in immunoglobulins, innate immune recognition molecules, acute phase proteins, regulatory proteins, and cell adhesion and cytoskeletal proteins; 6 PDE proteins from healthy plasma involved in regulatory proteins, cytoskeletal proteins and coagulation factors. Of these PDE proteins, haptoglobin, SERPINA10 protein, afamin precursor, haptoglobin precursor, apolipoprotein D, predicted peptidoglycan recognition protein L (PGRP-L) and keratan sulfate proteoglycan (KS-PG) were suggested to be potential footrot-associated factors. The PDE proteins PGRP-L and KS-PG were highlighted as potential biomarkers of footrot in cattle. The resulting protein lists and potential differentially expressed proteins may provide valuable information to increase understanding of plasma protein profiles in cattle and to assist studies of footrot-associated factors. PMID:23418487

  5. Heparan Sulfate Modification of the Transmembrane Receptor CD47 Is Necessary for Inhibition of T Cell Receptor Signaling by Thrombospondin-1*

    PubMed Central

    Kaur, Sukhbir; Kuznetsova, Svetlana A.; Pendrak, Michael L.; Sipes, John M.; Romeo, Martin J.; Li, Zhuqing; Zhang, Lijuan; Roberts, David D.

    2011-01-01

    Cell surface proteoglycans on T cells contribute to retroviral infection, binding of chemokines and other proteins, and are necessary for some T cell responses to the matricellular glycoprotein thrombospondin-1. The major cell surface proteoglycans expressed by primary T cells and Jurkat T cells have an apparent Mr > 200,000 and are modified with chondroitin sulfate and heparan sulfate chains. Thrombospondin-1 bound in a heparin-inhibitable manner to this proteoglycan and to a soluble form released into the medium. Based on mass spectrometry, knockdown, and immunochemical analyses, the proteoglycan contains two major core proteins as follows: amyloid precursor-like protein-2 (APLP2, apparent Mr 230,000) and CD47 (apparent Mr > 250,000). CD47 is a known thrombospondin-1 receptor but was not previously reported to be a proteoglycan. This proteoglycan isoform of CD47 is widely expressed on vascular cells. Mutagenesis identified glycosaminoglycan modification of CD47 at Ser64 and Ser79. Inhibition of T cell receptor signaling by thrombospondin-1 was lost in CD47-deficient T cells that express the proteoglycan isoform of APLP2, indicating that binding to APLP2 is not sufficient. Inhibition of CD69 induction was restored in CD47-deficient cells by re-expressing CD47 or an S79A mutant but not by the S64A mutant. Therefore, inhibition of T cell receptor signaling by thrombospondin-1 is mediated by CD47 and requires its modification at Ser64. PMID:21343308

  6. Homoserine as an Aspartic Acid Precursor for Synthesis of Proteoglycan Glycopeptide Containing Aspartic Acid and a Sulfated Glycan Chain.

    PubMed

    Yang, Weizhun; Ramadan, Sherif; Yang, Bo; Yoshida, Keisuke; Huang, Xuefei

    2016-12-02

    Among many hurdles in synthesizing proteoglycan glycopeptides, one challenge is the incorporation of aspartic acid in the peptide backbone and acid sensitive O-sulfated glycan chains. To overcome this, a new strategy was developed utilizing homoserine as an aspartic acid precursor. The conversion of homoserine to aspartic acid in the glycopeptide was successfully accomplished by late stage oxidation using (2,2,6,6-tetramethyl-piperidin-1-yl)oxyl (TEMPO) and bis(acetoxy)iodobenzene (BAIB). This is the first time that a glycopeptide containing aspartic acid and an O-sulfated glycan was synthesized.

  7. Experimental study using ER-YAG laser in discs: changes in glycosaminoglycan content and synthesis in discs

    NASA Astrophysics Data System (ADS)

    Maehara, Kazuyuki; Nakai, Sadaaki; Naga, Kumi; Nishimoto, Seiji

    2004-09-01

    Changes in discs after Er-Yag laser irradiation are scarcely reported. We made an experimental study using white rabbits and Er-Yag laser. Under general anesthesia, Er-Yag laser was irradiated into lumbar discs. Three or 8 weeks after irradiation, rabbits were sacrificed, and these discs were extracted. The quantitative analysis of the glycosaminoglycan content in the annulus fibrosus, and the incorporation of 35S-sulfate in chondroitin 4 sulfate were measured. The results showed, the increased incorporation of 35S-sulfate in chondroitin 4 sulfate and chondroitin 6 sulfates in groups of laser irradiation may indicate Er-Yag laser irradiation in nucleus pulposus, accelerated glycosaminoglycan production, in the annulus fibrosus. But no difference of unsaturated isomers of chondroitin 4 sulfate, and chondroitin 6 sulfate, and no difference of saturated isomer of keratan sulfate indicate, the influence of Er-Yag laser irradiation was not so high, as to bring the quantitative changes of matrix of annulus fibrosus in term of 8 weeks.

  8. Heparan sulfate proteoglycans undergo differential expression alterations in right sided colorectal cancer, depending on their metastatic character.

    PubMed

    Fernández-Vega, Iván; García-Suárez, Olivia; García, Beatriz; Crespo, Ainara; Astudillo, Aurora; Quirós, Luis M

    2015-10-20

    Heparan sulfate proteoglycans (HSPGs) are complex molecules involved in the growth, invasion and metastatic properties of cancerous cells. This study analyses the alterations in the expression patterns of these molecules in right sided colorectal cancer (CRC), both metastatic and non-metastatic. Twenty right sided CRCs were studied. A transcriptomic approach was used, employing qPCR to analyze both the expression of the enzymes involved in heparan sulfate (HS) chains biosynthesis, as well as the proteoglycan core proteins. Since some of these proteoglycans can also carry chondroitin sulfate (CS) chains, we include the study of the genes involved in the biosynthesis of these glycosaminoglycans. Immunohistochemical techniques were also used to analyze tissue expression of particular genes showing significant expression differences, of potential interest. Changes in proteoglycan core proteins differ depending on their location; those located intracellularly or in the extracellular matrix show very similar alteration patterns, while those located on the cell surface vary greatly depending on the nature of the tumor: glypicans 1, 3, 6 and betaglycan are affected in the non-metastatic tumors, whereas in the metastatic, only glypican-1 and syndecan-1 are modified, the latter showing opposing alterations in levels of RNA and of protein, suggesting post-transcriptional regulation in these tumors. Furthermore, in non-metastatic tumors, polymerization of glycosaminoglycan chains is modified, particularly affecting the synthesis of the tetrasaccharide linker and the initiation and elongation of CS chains, HS chains being less affected. Regarding the enzymes responsible for the modificaton of the HS chains, alterations were only found in non-metastatic tumors, affecting N-sulfation and the isoforms HS6ST1, HS3ST3B and HS3ST5. In contrast, synthesis of the CS chains suggests changes in epimerization and sulfation of the C4 and C2 in both types of tumor. Right sided CRCs show alterations in the expression of HSPGs, including the expression of the cell surface core proteins, many glycosiltransferases and some enzymes that modify the HS chains depending on the metastatic nature of the tumor, resulting more affected in non-metastatic ones. However, matrix proteoglycans and enzymes involved in CS fine structure synthesis are extensively modified independetly of the presence of lymph node metastasis.

  9. Immunoblotting assays for keratan sulfate.

    PubMed

    Yoon, Jung Hae; Brooks, Randolph; Halper, Jaroslava

    2002-07-15

    The detection of microquantities of glycosaminoglycans (GAGs) in biological samples has been hampered by the lack of sensitive methods. In this paper we describe the modification and development of three sensitive assays capable of detecting nanogram quantities of GAGs in biological samples. The first assay detects total GAGs. It is a modified Alcian blue dye precipitation assay in which the dye binds to the negatively charged GAGs in CsCl-fractionated extracts from chicken tendons. This assay compares favorably with the widely used uronic acid assay in terms of its sensitivity and ability to detect all classes of GAGs, including keratan sulfate (KS). Two other assays, dot-blotting and immunoblotting, detect KS in complex mixtures and can be easily adapted for the detection of other GAGs. Both take advantage of binding of carboxyl and sulfate groups of GAGs to trivalent neodymium. In dot-blotting, samples were directly blotted onto nitrocellulose membrane soaked in Nd(2)(SO(4))(3) buffer, and KS was detected with the monoclonal anti-KS 5-D-4 antibody and an avidin-biotin complex detection system. In immunoblotting, the samples were first separated in 28% polyacrylamide gels, transferred onto a Nd(2)(SO(4))(3)-soaked nitrocellulose membrane using a phosphate buffer system, and stained and developed using the same protocol as in dot-blotting. Whereas dot-blotting allows the use of very low quantities of samples because of its high sensitivity (lower detection limit was 5 ng), immunoblotting provides more specificity.

  10. The Role(s) of Heparan Sulfate Proteoglycan(s) in the wnt-1 Signaling Pathway

    DTIC Science & Technology

    1998-08-01

    First , the sequence of the cDNA, when compared to the genomic site of insertion of the P-element, revealed that the P-element is inserted 686 bp...stages 8 to 13 (Yoffe et al. 1995). We first examined whether ectopic expression of Wgts effectively restores the naked cuticle as it does in wg and...by Kjell~n and Lindahl, 1991) . HS/heparin N-deacetylase/N-sulfotransferase catalyzes N-deacetylation and N-sulfation that is the first and key step

  11. Dietary Keratan Sulfate from Shark Cartilage Modulates Gut Microbiota and Increases the Abundance of Lactobacillus spp.

    PubMed

    Shang, Qingsen; Li, Qinying; Zhang, Meifang; Song, Guanrui; Shi, Jingjing; Jiang, Hao; Cai, Chao; Hao, Jiejie; Li, Guoyun; Yu, Guangli

    2016-12-08

    Keratan sulfate (KS) represents an important family of glycosaminoglycans that are critical in diverse physiological processes. Recently, accumulating evidence has provided a wealth of information on the bioactivity of KS, which established it as an attractive candidate for drug development. However, although KS has been widely explored, less attention has been given to its effect on gut microbiota. Therefore, given that gut microbiota plays a pivotal role in health homeostasis and disease pathogenesis, we investigated here in detail the effect of KS on gut microbiota by high-throughput sequencing. As revealed by heatmap and principal component analysis, the mice gut microbiota was readily altered at different taxonomic levels by intake of low (8 mg/kg) and high dosage (40 mg/kg) of KS. Interestingly, KS exerted a differing effect on male and female microbiota. Specifically, KS induced a much more drastic increase in the abundance of Lactobacillus spp. in female (sixteen-fold) versus male mice (two-fold). In addition, combined with alterations in gut microbiota, KS also significantly reduced body weight while maintaining normal gut homeostasis. Altogether, we first demonstrated a sex-dependent effect of KS on gut microbiota and highlighted that it may be used as a novel prebiotic for disease management.

  12. Hyaluronate-binding proteins of murine brain.

    PubMed

    Marks, M S; Chi-Rosso, G; Toole, B P

    1990-01-01

    The distribution of hyaluronate-binding activity was determined in the soluble and membrane fractions derived from adult mouse brain by sonication in low-ionic-strength buffer. Approximately 60% of the total activity was recovered in the soluble fraction and 33% in membrane fractions. In both cases, the hyaluronate-binding activities were found to be of high affinity (KD = 10(-9) M), specific for hyaluronate, and glycoprotein in nature. Most of the hyaluronate-binding activity from the soluble fraction chromatographed in the void volume of Sepharose CL-4B and CL-6B. Approximately 50% of this activity was highly negatively charged, eluting from diethylaminoethyl (DEAE)-cellulose in 0.5 M NaCl, and contained chondroitin sulfate chains. This latter material also reacted with antibodies raised against cartilage link protein and the core protein of cartilage proteoglycan. Thus, the binding and physical characteristics of this hyaluronate-binding activity are consistent with those of a chondroitin sulfate proteoglycan aggregate similar to that found in cartilage. A 500-fold purification of this proteoglycan-like, hyaluronate-binding material was achieved by wheat germ agglutinin affinity chromatography, molecular sieve chromatography on Sepharose CL-6B, and ion exchange chromatography on DEAE-cellulose. Another class of hyaluronate-binding material (25-50% of that recovered) eluted from DEAE with 0.24 M NaCl; this material had the properties of a complex glycoprotein, did not contain chondroitin sulfate, and did not react with the antibodies against cartilage link protein and proteoglycan. Thus, adult mouse brain contains at least three different forms of hyaluronate-binding macromolecules. Two of these have properties similar to the link protein and proteoglycan of cartilage proteoglycan aggregates; the third is distinguishable from these entities.

  13. Proteoglycans: road signs for neurite outgrowth.

    PubMed

    Beller, Justin A; Snow, Diane M

    2014-02-15

    Proteoglycans in the central nervous system play integral roles as "traffic signals" for the direction of neurite outgrowth. This attribute of proteoglycans is a major factor in regeneration of the injured central nervous system. In this review, the structures of proteoglycans and the evidence suggesting their involvement in the response following spinal cord injury are presented. The review further describes the methods routinely used to determine the effect proteoglycans have on neurite outgrowth. The effects of proteoglycans on neurite outgrowth are not completely understood as there is disagreement on what component of the molecule is interacting with growing neurites and this ambiguity is chronicled in an historical context. Finally, the most recent findings suggesting possible receptors, interactions, and sulfation patterns that may be important in eliciting the effect of proteoglycans on neurite outgrowth are discussed. A greater understanding of the proteoglycan-neurite interaction is necessary for successfully promoting regeneration in the injured central nervous system.

  14. Changes in cat urinary glycosaminoglycans with age and in feline urologic syndrome.

    PubMed

    Pereira, Daionety A; Aguiar, Jair A K; Hagiwara, Mitika K; Michelacci, Yara M

    2004-04-07

    The aim of the present study was to characterize the urinary excretion of glycosaminoglycans in kittens and adult healthy cats, as well as in cats with a low urinary tract disease, the feline urologic syndrome (FUS). The main urinary glycosaminoglycan in cats was found to be chondroitin sulfate, with smaller amounts of dermatan sulfate and heparan sulfate. There was no difference in the urinary glycosaminoglycan concentration with sex, but a marked decrease occurred with age, due to chondroitin sulfate. Trace amounts of keratan sulfate were also detected in the urine of kittens, but not of healthy adult cats. Dermatan sulfate and heparan sulfate were the only glycosaminoglycans found in the urinary tract and kidney, and chondroitin sulfate was the only glycosaminoglycan found in the plasma. These data suggest that the main urinary glycosaminoglycan chondroitin sulfate is of systemic origin and filtered in the kidney, while the minor components dermatan sulfate and heparan sulfate may come from the urinary tract. The urinary glycosaminoglycan concentration was greatly decreased in animals with FUS, as compared to normal adults. We hypothesize that these low glycosaminoglycan levels reflect a damage to the bladder surface, resulting in absorption and/or degradation of the endogenous urinary glycosaminoglycans.

  15. Brain ageing changes proteoglycan sulfation, rendering perineuronal nets more inhibitory.

    PubMed

    Foscarin, Simona; Raha-Chowdhury, Ruma; Fawcett, James W; Kwok, Jessica C F

    2017-06-28

    Chondroitin sulfate (CS) proteoglycans in perineuronal nets (PNNs) from the central nervous system (CNS) are involved in the control of plasticity and memory. Removing PNNs reactivates plasticity and restores memory in models of Alzheimer's disease and ageing. Their actions depend on the glycosaminoglycan (GAG) chains of CS proteoglycans, which are mainly sulfated in the 4 (C4S) or 6 (C6S) positions. While C4S is inhibitory, C6S is more permissive to axon growth, regeneration and plasticity. C6S decreases during critical period closure. We asked whether there is a late change in CS-GAG sulfation associated with memory loss in aged rats. Immunohistochemistry revealed a progressive increase in C4S and decrease in C6S from 3 to 18 months. GAGs extracted from brain PNNs showed a large reduction in C6S at 12 and 18 months, increasing the C4S/C6S ratio. There was no significant change in mRNA levels of the chondroitin sulfotransferases. PNN GAGs were more inhibitory to axon growth than those from the diffuse extracellular matrix. The 18-month PNN GAGs were more inhibitory than 3-month PNN GAGs. We suggest that the change in PNN GAG sulfation in aged brains renders the PNNs more inhibitory, which lead to a decrease in plasticity and adversely affect memory.

  16. Liver heparan sulfate proteoglycans mediate clearance of triglyceride-rich lipoproteins independently of LDL receptor family members

    PubMed Central

    MacArthur, Jennifer M.; Bishop, Joseph R.; Stanford, Kristin I.; Wang, Lianchun; Bensadoun, André; Witztum, Joseph L.; Esko, Jeffrey D.

    2007-01-01

    We examined the role of hepatic heparan sulfate in triglyceride-rich lipoprotein metabolism by inactivating the biosynthetic gene GlcNAc N-deacetylase/N-sulfotransferase 1 (Ndst1) in hepatocytes using the Cre-loxP system, which resulted in an approximately 50% reduction in sulfation of liver heparan sulfate. Mice were viable and healthy, but they accumulated triglyceride-rich lipoprotein particles containing apoB-100, apoB-48, apoE, and apoCI-IV. Compounding the mutation with LDL receptor deficiency caused enhanced accumulation of both cholesterol- and triglyceride-rich particles compared with mice lacking only LDL receptors, suggesting that heparan sulfate participates in the clearance of cholesterol-rich lipoproteins as well. Mutant mice synthesized VLDL normally but showed reduced plasma clearance of human VLDL and a corresponding reduction in hepatic VLDL uptake. Retinyl ester excursion studies revealed that clearance of intestinally derived lipoproteins also depended on hepatocyte heparan sulfate. These findings show that under normal physiological conditions, hepatic heparan sulfate proteoglycans play a crucial role in the clearance of both intestinally derived and hepatic lipoprotein particles. PMID:17200715

  17. Knockdown of Zebrafish Lumican Gene (zlum) Causes Scleral Thinning and Increased Size of Scleral Coats*

    PubMed Central

    Yeh, Lung-Kun; Liu, Chia-Yang; Kao, Winston W.-Y.; Huang, Chang-Jen; Hu, Fung-Rong; Chien, Chung-Liang; Wang, I-Jong

    2010-01-01

    The lumican gene (lum), which encodes one of the major keratan sulfate proteoglycans (KSPGs) in the vertebrate cornea and sclera, has been linked to axial myopia in humans. In this study, we chose zebrafish (Danio rerio) as an animal model to elucidate the role of lumican in the development of axial myopia. The zebrafish lumican gene (zlum) spans ∼4.6 kb of the zebrafish genome. Like human (hLUM) and mouse (mlum), zlum consists of three exons, two introns, and a TATA box-less promoter at the 5′-flanking region of the transcription initiation site. Sequence analysis of the cDNA predicts that zLum encodes 344 amino acids. zLum shares 51% amino acid sequence identity with human lumican. Similar to hLUM and mlum, zlum mRNA is expressed in the eye and many other tissues, such as brain, muscle, and liver as well. Transgenic zebrafish harboring an enhanced GFP reporter gene construct downstream of a 1.7-kb zlum 5′-flanking region displayed enhanced GFP expression in the cornea and sclera, as well as throughout the body. Down-regulation of zlum expression by antisense zlum morpholinos manifested ocular enlargement resembling axial myopia due to disruption of the collagen fibril arrangement in the sclera and resulted in scleral thinning. Administration of muscarinic receptor antagonists, e.g. atropine and pirenzepine, effectively subdued the ocular enlargement caused by morpholinos in in vivo zebrafish larvae assays. The observation suggests that zebrafish can be used as an in vivo model for screening compounds in treating myopia. PMID:20551313

  18. [Stimulation of maturing and terminal differentiation by concanavalin A in rabbit permanent chondrocyte cultures].

    PubMed

    Yan, W Q; Yang, T S; Hou, L Z; Susuki, F; Kato, Y

    1994-12-01

    The effect of concanavalin A (Con A) on maturing and terminal differentiation in permanent chondrocyte cultures were examined. Chondrocytes isolated from permanent cartilage were seeded at low density and grown in MEM medium containing 10% fetal bovine serum, 50 micrograms/ml of ascorbic acid and antibiotics, at 37 degrees C under 50% CO2 in air. At 0.3% of low serum concentration, addition of Con A to the culture medium increased by 3- to 4-fold the incorporation of [35S] sulfate into large chondroitin sulfate proteoglycan that characteristically found in cartilage. Chemical analysis showed a 4-fold increase in the accumulation of macromolecular containing hexuronic acid in Con A-maintained cultures. The effect of Con A on [35S]sulfate incorporation into proteoglycan was greater than that of various growth factor or hormones. Brief exposure of the permanent chondrocytes to Con A (5 micrograms/ml) for 24 hours and subsequent incubation in its absence for 5-10 days resulted in 10- to 100-fold increase in alkaline phosphatase and binding of 1.25 (OH)2 vitamin D3 to cells. Treatment with Con A also resulted in 10- to 20-fold increase in calcium content and 45Ca incorporation into insoluble material. Methyl-D-mannopyranoside reversed the effect of Con A on [35S]sulfate incorporation into proteoglycan and alkaline phosphatase activity. Since other lectins, such as wheat germ agglutinin, lentil lectin, phytohemagglutinin, Ulex europeasu agglutinin and garden pea lectin had been tested to have little effect on [35S]sulfate incorporation into proteoglycans and induction of alkaline phosphatase activity, the Con A action on chondrocytes seems specific. These results indicate that Con A is a potent modulator of differentiation of chondrocytes, which induces the onset on a maturing and a terminal differentiation in chondrocytes, leading to extensive calcification of the extracellular matrix.

  19. The glycan keratan sulfate in inner ear crystals

    NASA Technical Reports Server (NTRS)

    Fermin, C. D.; Martin, D. S.; Li, Y. T.; Li, S. C.

    1995-01-01

    The otoconial matrix (OM) of chicks (Gallus domesticus) inner ear was analyzed. Histochemically the OM was reacted with phosphotungstic acid (PTA) and immunohistochemically with the monoclonal antibody antikeratan sulfate (antiKS). The OM was digested with the enzyme endo-beta-galactosidase (E beta Galase) or separated by 1D and 2D gel electrophoresis. PTA which reacts with glycoproteins precipitated the OM, suggesting that the OM contains glycoproteins. A central core in each crystal had no PTA staining, suggesting that the core lacked glycoproteins. Anti KS antibody stained the OM with increased density in older embryos as determined by color thresholding. E beta Galase, which cleaves the lactosamine repeating units in KS, decreased the immunostain by 30% in the OM and by 20% in the cartilage. The OM from the utricle, saccule and macula lagena contained similar molecular weight bands. Five dense bands in the OM were less dense in tissue and blood controls, suggesting that such bands are enriched in the OM. Isoelectric focusing of the OM showed a negatively charged high molecular weight smear not present in blood and faint in tissue controls. The high affinity of the OM for the cationic PTA stain, the strong immunohistochemical reaction of the OM with anti KS antibody and high molecular weight negative smear in 2D gels taken together suggest that: a) the OM contains large amounts of glycoproteins and glycans, one of which is keratan sulfate, because its immuno stain with antiKS antibody was decreased by the enzyme E beta Galase, b) the utricle, saccule and macula lagena may have similar composition, and c) the concentration of KS may increase gradually until complete mineralization of the OM is reached.

  20. Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar).

    PubMed

    Hannesson, Kirsten O; Ytteborg, Elisabeth; Takle, Harald; Enersen, Grethe; Bæverfjord, Grete; Pedersen, Mona E

    2015-08-01

    In the present study, the distribution of sulphated glycosaminoglycans (GAGs) in the developing vertebral column of Atlantic salmon (Salmo salar) at 700, 900, 1100 and 1400 d° was examined by light microscopy. The mineralization pattern was outlined by Alizarin red S and soft structures by Alcian blue. The temporal and spatial distribution patterns of different types of GAGs: chondroitin-4-sulphate/dermatan sulphate, chondroitin-6-sulphate, chondroitin-0-sulphate and keratan sulphate were addressed by immunohistochemistry using monoclonal antibodies against the different GAGs. The specific pattern obtained with the different antibodies suggests a unique role of the different GAG types in pattern formation and mineralization. In addition, the distribution of the different GAG types in normal and malformed vertebral columns from 15 g salmon was compared. A changed expression pattern of GAGs was found in the malformed vertebrae, indicating the involvement of these molecules during the pathogenesis. The molecular size of proteoglycans (PGs) in the vertebrae carrying GAGs was analysed with western blotting, and mRNA transcription of the PGs aggrecan, decorin, biglycan, fibromodulin and lumican by real-time qPCR. Our study reveals the importance of GAGs in development of vertebral column also in Atlantic salmon and indicates that a more comprehensive approach is necessary to completely understand the processes involved.

  1. Glycosaminoglycan in cerebrum, cerebellum and brainstem of young sheep brain with particular reference to compositional and structural variations of chondroitin-dermatan sulfate and hyaluronan.

    PubMed

    Kilia, Virginia; Skandalis, Spyros S; Theocharis, Achilleas D; Theocharis, Dimitrios A; Karamanos, Nikos K; Papageorgakopoulou, Nickoletta

    2008-09-01

    Recent advances in the structural biology of chondroitin sulfate chains have suggested important biological functions in the development of the brain. Several studies have demonstrated that the composition of chondroitin sulfate chains changes with aging and normal brain maturation. In this study, we determined the concentration of all glycosaminoglycan types, i.e. chondroitin sulfate, dermatan sulfate, keratan sulfate, heparan sulfate, hyaluronan and chondroitin in cerebrum, cerebellum and brainstem of young sheep brain. In all cases, chondroitin sulfate was the predominant glycosaminoglycan type, comprising about 54-58% of total glycosaminoglycans, with hyaluronan being present also in significant amounts of about 19-28%. Of particular interest was the increased presence of the disulfated disaccharides and dermatan sulfate in cerebellum and brainstem, respectively, as well as the detectable and measurable occurrence of chondroitin in young sheep brain. Among the three brain areas, cerebrum was found to be significantly richer in chondroitin sulfate and hyaluronan, two major extracellular matrix components. These findings imply that the extracellular matrix of the cerebrum is different from those of cerebellum and brainstem, and probably this fact is related to the particular histological and functional characteristics of each anatomic area of the brain.

  2. EGFR Activation Mediates Inhibition of Axon Regeneration by Myelin and Chondroitin Sulfate Proteoglycans

    NASA Astrophysics Data System (ADS)

    Koprivica, Vuk; Cho, Kin-Sang; Park, Jong Bae; Yiu, Glenn; Atwal, Jasvinder; Gore, Bryan; Kim, Jieun A.; Lin, Estelle; Tessier-Lavigne, Marc; Chen, Dong Feng; He, Zhigang

    2005-10-01

    Inhibitory molecules associated with myelin and the glial scar limit axon regeneration in the adult central nervous system (CNS), but the underlying signaling mechanisms of regeneration inhibition are not fully understood. Here, we show that suppressing the kinase function of the epidermal growth factor receptor (EGFR) blocks the activities of both myelin inhibitors and chondroitin sulfate proteoglycans in inhibiting neurite outgrowth. In addition, regeneration inhibitors trigger the phosphorylation of EGFR in a calcium-dependent manner. Local administration of EGFR inhibitors promotes significant regeneration of injured optic nerve fibers, pointing to a promising therapeutic avenue for enhancing axon regeneration after CNS injury.

  3. Site-specific identification of heparan and chondroitin sulfate glycosaminoglycans in hybrid proteoglycans.

    PubMed

    Noborn, Fredrik; Gomez Toledo, Alejandro; Green, Anders; Nasir, Waqas; Sihlbom, Carina; Nilsson, Jonas; Larson, Göran

    2016-10-03

    Heparan sulfate (HS) and chondroitin sulfate (CS) are complex polysaccharides that regulate important biological pathways in virtually all metazoan organisms. The polysaccharides often display opposite effects on cell functions with HS and CS structural motifs presenting unique binding sites for specific ligands. Still, the mechanisms by which glycan biosynthesis generates complex HS and CS polysaccharides required for the regulation of mammalian physiology remain elusive. Here we present a glycoproteomic approach that identifies and differentiates between HS and CS attachment sites and provides identity to the core proteins. Glycopeptides were prepared from perlecan, a complex proteoglycan known to be substituted with both HS and CS chains, further digested with heparinase or chondroitinase ABC to reduce the HS and CS chain lengths respectively, and thereafter analyzed by nLC-MS/MS. This protocol enabled the identification of three consensus HS sites and one hybrid site, carrying either a HS or a CS chain. Inspection of the amino acid sequence at the hybrid attachment locus indicates that certain peptide motifs may encode for the chain type selection process. This analytical approach will become useful when addressing fundamental questions in basic biology specifically in elucidating the functional roles of site-specific glycosylations of proteoglycans.

  4. Molecular Testing of 163 Patients with Morquio A (Mucopolysaccharidosis IVA) Identifies 39 Novel GALNS Mutations

    PubMed Central

    Morrone, A; Tylee, K.L.; Al-Sayed, M; Brusius-Facchin, A.C.; Caciotti, A.; Church, H.J.; Coll, M.J.; Davidson, K.; Fietz, M.J.; Gort, L.; Hegde, M.; Kubaski, F.; Lacerda, L.; Laranjeira, F.; Leistner-Segal, S.; Mooney, S.; Pajares, S.; Pollard, L.; Riberio, I.; Wang, R.Y.; Miller, N.

    2014-01-01

    Morquio A (Mucopolysaccharidosis IVA; MPS IVA) is an autosomal recessive lysosomal storage disorder caused by partial or total deficiency of the enzyme galactosamine-6-sulfate sulfatase (GALNS; also known as N-acetylgalactosamine-6-sulfate sulfatase) encoded by the GALNS gene. Patients who inherit two mutated GALNS gene alleles produce protein with decreased ability to degrade the glycosaminoglycans (GAGs) keratan sulfate and chondroitin 6-sulfate, thereby causing GAG accumulation within lysosomes and consequently pleiotropic disease. GALNS mutations occur throughout the gene and many mutations are identified only in single patients or families, causing difficulties both in mutation detection and interpretation. In this study, molecular analysis of 163 patients with Morquio A identified 99 unique mutations in the GALNS gene believed to negatively impact GALNS protein function, of which 39 are previously unpublished, together with 26 single-nucleotide polymorphisms. Recommendations for the molecular testing of patients, clear reporting of sequence findings, and interpretation of sequencing data are provided. PMID:24726177

  5. Molecular interactions between chondroitin-dermatan sulfate and growth factors/receptors/matrix proteins.

    PubMed

    Mizumoto, Shuji; Yamada, Shuhei; Sugahara, Kazuyuki

    2015-10-01

    Recent functional studies on chondroitin sulfate-dermatan sulfate (CS-DS) demonstrated its indispensable roles in various biological events including brain development and cancer. CS-DS proteoglycans exert their physiological activity through interactions with specific proteins including growth factors, cell surface receptors, and matrix proteins. The characterization of these interactions is essential for regulating the biological functions of CS-DS proteoglycans. Although amino acid sequences on the bioactive proteins required for these interactions have already been elucidated, the specific saccharide sequences involved in the binding of CS-DS to target proteins have not yet been sufficiently identified. In this review, recent findings are described on the interaction between CS-DS and some proteins which are especially involved in the central nervous system and cancer development/metastasis. Copyright © 2015. Published by Elsevier Ltd.

  6. Recombinant Domain V of Human Perlecan Is a Bioactive Vascular Proteoglycan.

    PubMed

    Rnjak-Kovacina, Jelena; Tang, Fengying; Lin, Xiaoting; Whitelock, John M; Lord, Megan S

    2017-12-01

    The C-terminal domain V of the extracellular matrix proteoglycan perlecan plays unique and often divergent roles in a number of biological processes, including angiogenesis, vascular cell interactions, wound healing, and autophagy. Recombinant forms of domain V have been proposed as therapeutic agents for the treatment of cancer, stroke, and the development of cardiovascular devices and bioartificial tissues. However, the effect of domain V appears to be related to the differences in domain V structure and function observed in different expression systems and environments and exactly how this occurs is not well understood. In this study, the sequence from amino acid 3626 to 4391 of the perlecan protein core, which includes domain V, is expressed in HEK-293 cells and purified as a secreted product from conditioned media. This recombinant domain V (rDV) is expressed as a proteoglycan decorated with heparan sulfate and chondroitin sulfate chains and supports endothelial cell interactions to the same extent as full-length perlecan. This expression system serves as an important model of recombinant proteoglycan expression, as well as a source of biologically active rDV for therapeutic applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Sequence Analysis and Domain Motifs in the Porcine Skin Decorin Glycosaminoglycan Chain*

    PubMed Central

    Zhao, Xue; Yang, Bo; Solakylidirim, Kemal; Joo, Eun Ji; Toida, Toshihiko; Higashi, Kyohei; Linhardt, Robert J.; Li, Lingyun

    2013-01-01

    Decorin proteoglycan is comprised of a core protein containing a single O-linked dermatan sulfate/chondroitin sulfate glycosaminoglycan (GAG) chain. Although the sequence of the decorin core protein is determined by the gene encoding its structure, the structure of its GAG chain is determined in the Golgi. The recent application of modern MS to bikunin, a far simpler chondroitin sulfate proteoglycans, suggests that it has a single or small number of defined sequences. On this basis, a similar approach to sequence the decorin of porcine skin much larger and more structurally complex dermatan sulfate/chondroitin sulfate GAG chain was undertaken. This approach resulted in information on the consistency/variability of its linkage region at the reducing end of the GAG chain, its iduronic acid-rich domain, glucuronic acid-rich domain, and non-reducing end. A general motif for the porcine skin decorin GAG chain was established. A single small decorin GAG chain was sequenced using MS/MS analysis. The data obtained in the study suggest that the decorin GAG chain has a small or a limited number of sequences. PMID:23423381

  8. Transmembrane proteoglycans control stretch-activated channels to set cytosolic calcium levels

    PubMed Central

    Gopal, Sandeep; Søgaard, Pernille; Multhaupt, Hinke A.B.; Pataki, Csilla; Okina, Elena; Xian, Xiaojie; Pedersen, Mikael E.; Stevens, Troy; Griesbeck, Oliver; Park, Pyong Woo; Pocock, Roger

    2015-01-01

    Transmembrane heparan sulfate proteoglycans regulate multiple aspects of cell behavior, but the molecular basis of their signaling is unresolved. The major family of transmembrane proteoglycans is the syndecans, present in virtually all nucleated cells, but with mostly unknown functions. Here, we show that syndecans regulate transient receptor potential canonical (TRPCs) channels to control cytosolic calcium equilibria and consequent cell behavior. In fibroblasts, ligand interactions with heparan sulfate of syndecan-4 recruit cytoplasmic protein kinase C to target serine714 of TRPC7 with subsequent control of the cytoskeleton and the myofibroblast phenotype. In epidermal keratinocytes a syndecan–TRPC4 complex controls adhesion, adherens junction composition, and early differentiation in vivo and in vitro. In Caenorhabditis elegans, the TRPC orthologues TRP-1 and -2 genetically complement the loss of syndecan by suppressing neuronal guidance and locomotory defects related to increases in neuronal calcium levels. The widespread and conserved syndecan–TRPC axis therefore fine tunes cytoskeletal organization and cell behavior. PMID:26391658

  9. Decorin inhibits cell migration through a process requiring its glycosaminoglycan side chain.

    PubMed

    Merle, B; Durussel, L; Delmas, P D; Clézardin, P

    1999-12-01

    Several studies overwhelmingly support the notion that decorin (DCN) is involved in matrix assembly, and in the control of cell adhesion and proliferation. However, nothing is known about the role of DCN during cell migration. Cell migration is a tightly regulated process which requires both adhesion (at the leading edge of the cell) and de-adhesion (at the trailing edge of the cell) from the substratum. We have determined in this study the effect of DCN on MG-63 osteosarcoma cell migration and have analyzed whether its effect is mediated by the protein core and/or the glycosaminoglycan side chain. DCN impeded the migration-promoting effect of matrix molecules (fibronectin, collagen type I) known to interact with the proteoglycan. Conversely, DCN did not counteract the migration-promoting effect of fibrinogen lacking proteoglycan affinity. DCN bearing dermatan-sulfate chains (i.e., skin and cartilage DCN) was about 20-fold more effective in inhibiting cell migration than DCN bearing chondroitin-sulfate chains (i.e., bone DCN). In addition, chondroitinase AC-treatment of cartilage DCN (which specifically removes chondroitin-sulfate chains) did not attenuate the inhibitory effect of this proteoglycan, while cartilage DCN deprived of both chondroitin- and dermatan-sulfate chains failed to alter cell migration promoted by either fibronectin or its heparin- and cell-binding domains. These data assert that the dermatan-sulfate chains of DCN are responsible for a negative influence on cell migration. However, isolated glycosaminoglycans failed to alter cell migration promoted by fibronectin, indicating that strongly negatively charged glycosaminoglycans alone cannot account for the impaired cell motility seen with DCN. Overall, these results show that the inhibitory action of DCN is dependent of substratum binding, is differentially mediated by its glycosaminoglycan side chains (chondroitin-sulfate vs. dermatan-sulfate chains), and is independent of a steric hindrance effect exerted by its glycosaminoglycan side chains. Copyright 1999 Wiley-Liss, Inc.

  10. Optimization and Implementation of Long Nerve Allografts

    DTIC Science & Technology

    2014-10-01

    chondroitin   sulfate  chains  (CS56 immunolabeling),  myelin...3     CS56  antibody  labels  the  side-­‐chains  of   chondroitin   sulfate  proteoglycans.    All  processing...CS56  immunolabeling    showed  the   three  processing  methods  effectively  eliminate  the   chondroitin   sulfate

  11. C4St-1 and Chondroitin Sulfate in Stromal Control of wht Signaling in Breast Cancer

    DTIC Science & Technology

    2012-02-01

    Molecules of the tumor microenvironment play a critical role in tumor progression 1-4. The proteoglycan chondroitin sulfate , and chondroitin ...its role in breast cancer progression are not well understood. We investigated a novel chondroitin sulfate -based mechanism of tumor-stromal...cancer cells through the establishment of a microenvironment enriched in CS-E, a chondroitin sulfate product of C4ST-1. For this, we wanted to firstly

  12. Aggrecan-Like Biomimetic Proteoglycans (BPGs) Composed of Natural Chondroitin Sulfate Bristles Grafted onto Poly(acrylic acid) Core for Molecular Engineering of the Extracellular Matrix.

    PubMed

    Prudnikova, K; Lightfoot Vidal, S E; Sarkar, S; Yu, T; Yucha, R W; Ganesh, N; Penn, L S; Han, L; Schauer, C L; Vresilovic, E J; Marcolongo, M S

    2018-05-10

    Biomimetic proteoglycans (BPGs) were designed to mimic the three-dimensional (3D) bottlebrush architecture of natural extracellular matrix (ECM) proteoglycans, such as aggrecan. BPGs were synthesized by grafting native chondroitin sulfate bristles onto a synthetic poly(acrylic acid) core to form BPGs at a molecular weight of approximately ∼1.6 MDa. The aggrecan mimics were characterized chemically, physically, and structurally, confirming the 3D bottlebrush architecture as well as a level of water uptake, which is greater than that of the natural proteoglycan, aggrecan. Aggrecan mimics were cytocompatible at physiological concentrations. Fluorescently labeled BPGs were injected into the nucleus pulposus of the intervertebral disc ex vivo and were retained in tissue before and after static loading and equilibrium conditioning. BPGs infiltrated the tissue, distributed and integrated with the ECM on a molecular scale, in the absence of a bolus, thus demonstrating a new molecular approach to tissue repair: molecular matrix engineering. Molecular matrix engineering may compliment or offer an acellular alternative to current regenerative medicine strategies. Aggrecan is a natural biomolecule that is essential for connective tissue hydration and mechanics. Aggrecan is composed of negatively charged chondroitin sulfate bristles attached to a protein core in a bottlebrush configuration. With age and degeneration, enzymatic degradation of aggrecan outpaces cellular synthesis resulting in a loss of this important molecule. We demonstrate a novel biomimetic molecule composed of natural chondroitin sulfate bristles grafted onto an enzymatically-resistant synthetic core. Our molecule mimics a 3D architecture and charge density of the natural aggrecan, can be delivered via a simple injection and is retained in tissue after equilibrium conditioning and loading. This novel material can serve as a platform for molecular repair, drug delivery and tissue engineering in regenerative medicine approaches. Copyright © 2018. Published by Elsevier Ltd.

  13. Differential Effects of Fibromodulin Deficiency on Mouse Mandibular Bones and Teeth: A Micro-CT Time Course Study

    PubMed Central

    Goldberg, Michel; Marchadier, Arnaud; Vidal, Catherine; Harichane, Yassine; Kamoun-Goldrat, Agnès; Kellermann, Odile; Kilts, Tina; Young, Marian

    2011-01-01

    Fibromodulin (Fmod) is a keratan sulfate small leucine-rich proteoglycan which is enriched in bones and teeth. In order to determine its functions on bone and tooth mineralization we characterized the phenotype of Fmod-deficient (Fmod-KO) mice using a new-generation microfocus computerized tomography system (micro-CT) and software allowing advanced visualization of 3-D data. Three-week-old and 10- week-old Fmod-KO mandibles and teeth were compared with those of age-matched wild-type (WT) mice. In both young and mature mice the Fmod-KO mandibles were hypomineralized, especially the posterior (proximal) part of the mandible as it appeared to be the main target of the molecule deficiency whereas less extensive alterations were found in the alveolar bone. In transverse sections, larger marrow spaces were observed in the Fmod-KO mice compared with age-matched young or mature WT mice. Quantitative evaluation of the pulp volume of the first molar and 3-D reconstructions suggested that dentinogenesis was diminished in 3-week-old Fmod-KO teeth. In contrast, increased dentin formation was found in 10-week-old Fmod-KO mice and it was accompanied by a reduced pulp volume. Thus, the differential effects of Fmod deficiency on bones and teeth appear to diverge in adult mice. This may result from the previously reported differences in the molecular weight of Fmod in the 2 tissues or from compensatory mechanisms due to the overexpression of DSP and DMP-1 in the dental pulp of Fmod-KO. It is also possible that a single molecule plays diverging roles in a tissue-specific or region-specific manner. PMID:21597266

  14. Multiple bidirectional alterations of phenotype and changes in proliferative potential during the in vitro and in vivo passage of clonal mast cell populations derived from mouse peritoneal mast cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kanakura, Y.; Thompson, H.; Nakano, T.

    1988-09-01

    Mouse peritoneal mast cells (PMC) express a connective tissue-type mast cell (CTMC) phenotype, including reactivity with the heparin-binding fluorescent dye berberine sulfate and incorporation of (35S) sulfate predominantly into heparin proteoglycans. When PMC purified to greater than 99% purity were cultured in methylcellulose with IL-3 and IL-4, approximately 25% of the PMC formed colonies, all of which contained both berberine sulfate-positive and berberine sulfate-negative mast cells. When these mast cells were transferred to suspension culture, they generated populations that were 100% berberine sulfate-negative, a characteristic similar to that of mucosal mast cells (MMC), and that synthesized predominantly chondroitin sulfate (35S)more » proteoglycans. When ''MMC-like'' cultured mast cells derived from WBB6F1-+/+ PMC were injected into the peritoneal cavities of mast cell-deficient WBB6F1-W/Wv mice, the adoptively transferred mast cell population became 100% berberine sulfate-positive. In methylcellulose culture, these ''second generation PMC'' formed clonal colonies containing both berberine sulfate-positive and berberine sulfate-negative cells, but exhibited significantly less proliferative ability than did normal +/+ PMC. Thus, clonal mast cell populations initially derived from single PMC exhibited multiple and bidirectional alterations between CTMC-like and MMC-like phenotypes. However, this process was associated with a progressive diminution of the mast cells' proliferative ability.« less

  15. Molecular Determinants Fundamental to Axon Regeneration after SCI

    DTIC Science & Technology

    2012-10-01

    functions. In the mammalian spinal cord, axon regeneration is frustrated by inhibitors such as chondroitin sulfate proteoglycans (CSPGs) expressed by...CG, Becker T (2002) Repellent guidance of regeneration optic axons by chondroitin sulfate glycosaminoglycans in zebrafish. J Neurosci 22(3): 842-853...Shen Y, Tenney AP, Busch SA, Horn KP, Cuascut FX, Liu K, He Z, Silver J, Flanagan JG (2009) PTPσ is a receptor for chondroitin sulfate

  16. Optimization and Implementation of Long Nerve Allografts

    DTIC Science & Technology

    2013-03-01

    chondroitin   sulfate  proteoglycans.    All  processing  methods   include  the  same  treatment  step  with...methods  effectively  eliminate  the   chondroitin   sulfate  side-­‐chains  after  detergent   extractions...the  three   processing  methods  effectively  eliminate  the   chondroitin   sulfate  side-­‐chains  and  yet

  17. Chondroitin sulfatases differentially regulate Wnt signaling in prostate stem cells through effects on SHP2, phospho-ERK1/2, and Dickkopf Wnt signaling pathway inhibitor (DKK3)

    PubMed Central

    Bhattacharyya, Sumit; Feferman, Leo; Tobacman, Joanne K.

    2017-01-01

    The chondroitin sulfatases N-acetylgalactosamine-4-sulfatase (ARSB) and galactosamine-N-acetyl-6-sulfatase (GALNS) remove either the 4-sulfate group at the non-reducing end of chondroitin 4-sulfate (C4S) and dermatan sulfate, or the 6-sulfate group of chondroitin 6-sulfate, chondroitin 4,6-disulfate (chondroitin sulfate E), or keratan sulfate. In human prostate cancer tissues, the ARSB activity was reduced and the GALNS activity was increased, compared to normal prostate tissue. In human prostate stem cells, when ARSB was reduced by silencing or GALNS was increased by overexpression, activity of SHP2, the ubiquitous non-receptor tyrosine phosphatase, declined, attributable to increased binding of SHP2 with C4S. This led to increases in phospho-ERK1/2, Myc/Max nuclear DNA binding, DNA methyltransferase (DNMT) activity and expression, and methylation of the Dickkopf Wnt signaling pathway inhibitor (DKK)3 promoter and to reduced DKK3 expression. Since DKK3 negatively regulates Wnt/β-catenin signaling, silencing of ARSB or overexpression of GALNS disinhibited (increased) Wnt/β-catenin signaling. These findings indicate that the chondroitin sulfatases can exert profound effects on Wnt-mediated processes, due to epigenetic effects that modulate Wnt signaling. PMID:29245974

  18. Is there any scientific evidence for the use of glucosamine in the management of human osteoarthritis?

    PubMed Central

    2012-01-01

    Glucosamine in its acetylated form is a natural constituent of some glycosaminoglycans (for example, hyaluronic acid and keratan sulfate) in the proteoglycans found in articular cartilage, intervertebral disc and synovial fluid. Glucosamine can be extracted and stabilized by chemical modification and used as a drug or a nutraceutical. It has been approved for the treatment of osteoarthritis (OA) in Europe to promote cartilage and joint health and is sold over the counter as a dietary supplement in the United States. Various formulations of glucosamine have been tested, including glucosamine sulfate and glucosamine hydrochloride. In vitro and in vivo studies have uncovered glucosamine's mechanisms of action on articular tissues (cartilage, synovial membrane and subchondral bone) and justified its efficacy by demonstrating structure-modifying and anti-inflammatory effects at high concentrations. However, results from clinical trials have raised many concerns. Pharmacokinetic studies have shown that glucosamine is easily absorbed, but the current treatment doses (for example, 1,500 mg/day) barely reach the required therapeutic concentration in plasma and tissue. The symptomatic effect size of glucosamine varies greatly depending on the formulation used and the quality of clinical trials. Importantly, the effect size reduces when evidence is accumulated chronologically and evidence for the structure-modifying effects of glucosamine are sparse. Hence, glucosamine was at first recommended by EULAR and OARSI for the management of knee pain and structure improvement in OA patients, but not in the most recent NICE guidelines. Consequently, the published recommendations for the management of OA require revision. Glucosamine is generally safe and although there are concerns about potential allergic and salt-related side effects of some formulations, no major adverse events have been reported so far. This paper examines all the in vitro and in vivo evidence for the mechanism of action of glucosamine as well as reviews the results of clinical trials. The pharmacokinetics, side effects and differences observed with different formulations of glucosamine and combination therapies are also considered. Finally, the importance of study design and criteria of evaluation are highlighted as new compounds represent new interesting options for the management of OA. PMID:22293240

  19. Is there any scientific evidence for the use of glucosamine in the management of human osteoarthritis?

    PubMed

    Henrotin, Yves; Mobasheri, Ali; Marty, Marc

    2012-01-30

    Glucosamine in its acetylated form is a natural constituent of some glycosaminoglycans (for example, hyaluronic acid and keratan sulfate) in the proteoglycans found in articular cartilage, intervertebral disc and synovial fluid. Glucosamine can be extracted and stabilized by chemical modification and used as a drug or a nutraceutical. It has been approved for the treatment of osteoarthritis (OA) in Europe to promote cartilage and joint health and is sold over the counter as a dietary supplement in the United States. Various formulations of glucosamine have been tested, including glucosamine sulfate and glucosamine hydrochloride. In vitro and in vivo studies have uncovered glucosamine's mechanisms of action on articular tissues (cartilage, synovial membrane and subchondral bone) and justified its efficacy by demonstrating structure-modifying and anti-inflammatory effects at high concentrations. However, results from clinical trials have raised many concerns. Pharmacokinetic studies have shown that glucosamine is easily absorbed, but the current treatment doses (for example, 1,500 mg/day) barely reach the required therapeutic concentration in plasma and tissue. The symptomatic effect size of glucosamine varies greatly depending on the formulation used and the quality of clinical trials. Importantly, the effect size reduces when evidence is accumulated chronologically and evidence for the structure-modifying effects of glucosamine are sparse. Hence, glucosamine was at first recommended by EULAR and OARSI for the management of knee pain and structure improvement in OA patients, but not in the most recent NICE guidelines. Consequently, the published recommendations for the management of OA require revision. Glucosamine is generally safe and although there are concerns about potential allergic and salt-related side effects of some formulations, no major adverse events have been reported so far. This paper examines all the in vitro and in vivo evidence for the mechanism of action of glucosamine as well as reviews the results of clinical trials. The pharmacokinetics, side effects and differences observed with different formulations of glucosamine and combination therapies are also considered. Finally, the importance of study design and criteria of evaluation are highlighted as new compounds represent new interesting options for the management of OA.

  20. Border patrol: insights into the unique role of perlecan/heparan sulfate proteoglycan 2 at cell and tissue borders.

    PubMed

    Farach-Carson, Mary C; Warren, Curtis R; Harrington, Daniel A; Carson, Daniel D

    2014-02-01

    The extracellular matrix proteoglycan (ECM) perlecan, also known as heparan sulfate proteoglycan 2 or HSPG2, is one of the largest (>200 nm) and oldest (>550 M years) extracellular matrix molecules. In vertebrates, perlecan's five-domain structure contains numerous independently folding modules with sequence similarities to other ECM proteins, all connected like cars into one long, diverse complex train following a unique N-terminal domain I decorated with three long glycosaminoglycan chains, and an additional glycosaminoglycan attachment site in the C-terminal domain V. In lower invertebrates, perlecan is not typically a proteoglycan, possessing the majority of the core protein modules, but lacking domain I where the attachment sites for glycosaminoglycan chains are located. This suggests that uniting the heparan sulfate binding growth factor functions of domain I and the core protein functions of the rest of the molecule in domains II-V occurred later in evolution for a new functional purpose. In this review, we surveyed several decades of pertinent literature to ask a fundamental question: Why did nature design this protein uniquely as an extraordinarily long multifunctional proteoglycan with a single promoter regulating expression, rather than separating these functions into individual proteins that could be independently regulated? We arrived at the conclusion that the concentration of perlecan at functional borders separating tissues and tissue layers is an ancient key function of the core protein. The addition of the heparan sulfate chains in domain I likely occurred as an additional means of binding the core protein to other ECM proteins in territorial matrices and basement membranes, and as a means to reserve growth factors in an on-site depot to assist with rapid repair of those borders when compromised, such as would occur during wounding. We propose a function for perlecan that extends its role from that of an extracellular scaffold, as we previously suggested, to that of a critical agent for establishing and patrolling tissue borders in complex tissues in metazoans. We also propose that understanding these unique functions of the individual portions of the perlecan molecule can provide new insights and tools for engineering of complex multi-layered tissues including providing the necessary cues for establishing neotissue borders. © 2013.

  1. Border Patrol: Insights into the Unique Role of Perlecan/Heparan Sulfate Proteoglycan2 at Cell and Tissue Borders

    PubMed Central

    Farach-Carson, Mary C.; Warren, Curtis R.; Harrington, Daniel A.; Carson, Daniel D.

    2013-01-01

    The extracellular matrix proteoglycan (ECM) perlecan, also known as heparan sulfate proteoglycan 2 or HSPG2, is one of the largest (>200 nm) and oldest (>550M years) extracellular matrix molecules. In vertebrates, perlecan’s five-domain structure contains numerous independently folding modules with sequence similarities to other ECM proteins, all connected like cars into one long, diverse complex train following a unique N-terminal domain I decorated with three long glycosaminoglycan chains, and an additional glycosaminoglycan attachment site in the C-terminal domain V. In lower invertebrates, perlecan is not typically a proteoglycan, possessing the majority of the core protein modules, but lacking domain I where the attachment sites for glycosaminoglycan chains are located. This suggests that uniting the heparan sulfate binding growth factor functions of domain I and the core protein functions of the rest of the molecule in domains II-V occurred later in evolution for a new functional purpose. In this review, we surveyed several decades of pertinent literature to ask a fundamental question: Why did nature design this protein uniquely as an extraordinarily long multifunctional proteoglycan with a single promoter regulating expression, rather than separating these functions into individual proteins that could be independently regulated? We arrived at the conclusion that the concentration of perlecan at functional borders separating tissues and tissue layers is an ancient key function of the core protein. The addition of the heparan sulfate chains in domain I likely occurred as an additional means of binding the core protein to other ECM proteins in territorial matrices and basement membranes, and as a means to reserve growth factors in an on-site depot to assist with rapid repair of those borders when compromised, such as would occur during wounding. We propose a function for perlecan that extends its role from that of an extracellular scaffold, as we previously suggested, to that of a critical agent for establishing and patrolling tissue borders in complex tissues in metazoans. We also propose that understanding these unique functions of the individual portions of the perlecan molecule can provide new insights and tools for engineering of complex multi-layered tissues including providing the necessary cues for establishing neotissue borders. PMID:24001398

  2. Validated high-performance anion-exchange chromatography with pulsed amperometric detection method for the determination of residual keratan sulfate and other glucosamine impurities in sodium chondroitin sulfate.

    PubMed

    Bottelli, Susanna; Grillo, Gianluca; Barindelli, Edoardo; Nencioni, Alessandro; Di Maria, Alessandro; Fossati, Tiziano

    2017-07-07

    An efficient and sensitive analytical method based on high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) was devised for the determination of glucosamine (GlcN) in sodium chondroitin sulfate (CS). Glucosamine (GlcN) is intended as marker of residual keratan sulfate (KS) and other impurities generating glucosamine by acidic hydrolyzation. The latter brings CS and KS to their respective monomers. Since GlcN is present only in KS we developed a method that separates GlcN from GalN, the principal hydrolytic product of CS, and then we validated it in order to quantify GlcN. Method validation was performed by spiking CS raw material with known amounts of KS. Detection limit was 0.5% of KS in CS (corresponding to 0.1μg/ml), and the linear range was 0.5-5% of KS in CS (corresponding to 0.1-1μg/ml). The optimized analysis was carried out on an ICS-5000 system (Dionex, Sunnyvale, CA, USA) equipped with a Dionex Amino Trap guard column (3mm×30mm), Dionex CarboPac-PA20 (3mm×30mm) and a Dionex CarboPac-PA20 analytical column (3mm×150mm) using gradient elution at a 0.5ml/min flow rate. Regression equations revealed good linear relationship (R 2 =0.99, n=5) within the test ranges. Quality parameters, including precision and accuracy, were fully validated and found to be satisfactory. The fully validated HPAEC-PAD method was readily applied for the quantification of residual KS in CS in several raw materials and USP/EP reference substance. Results confirmed that the HPAEC-PAD method is more specific than the electrophoretic method for related substance reported in EP and provides sensitive determination of KS in acid-hydrolyzed CS samples, enabling the quantitation of KS and other impurities (generating glucosamine) in CS. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Concentration determination of collagen and proteoglycan in bovine nasal cartilage by Fourier transform infrared imaging and PLS

    NASA Astrophysics Data System (ADS)

    Zhang, Xuexi; Xiao, Zhi-Yan; Yin, Jianhua; Xia, Yang

    2014-09-01

    Fourier transform infrared imaging (FTIRI) combined with chemometrics can be used to detect the structure of bio-macromolecule, measure the concentrations of some components, and so on. In this study, FTIRI with Partial Least-Squares (PLS) regression was applied to study the concentration of two main components in bovine nasal cartilage (BNC), collagen and proteoglycan. An infrared spectrum library was built by mixing the collagen and chondroitin 6-sulfate (main of proteoglycan) at different ratios. Some pretreatments are needed for building PLS model. FTIR images were collected from BNC sections at 6.25μm and 25μm pixel size. The spectra extracted from BNC-FTIR images were imported into the PLS regression program to predict the concentrations of collagen and proteoglycan. These PLS-determined concentrations are agreed with the result in our previous work and biochemical analytical results. The prediction shows that the concentrations of collagen and proteoglycan in BNC are comparative on the whole. However, the concentration of proteoglycan is a litter higher than that of collagen, to some extent.

  4. N-linked oligosaccharides on chondroitin 6-sulfotransferase-1 are required for production of the active enzyme, Golgi localization, and sulfotransferase activity toward keratan sulfate.

    PubMed

    Yusa, Akiko; Kitajima, Ken; Habuchi, Osami

    2006-07-21

    We have shown previously that purified chondroitin 6-sulfotransferase-1 (C6ST-1) was a glycoprotein abundant in N-linked oligosaccharides and could sulfate both chondroitin (C6ST activity) and keratan sulfate (KSST activity); however, functional roles of the N-glycans have remained unclear. In the present study, we show essential roles of N-glycans attached to C6ST-1 in the generation of the active enzyme and in its KSST activity. Treatment with tunicamycin of COS-7 cells transfected with C6ST-1 cDNA totally abolished production of the active C6ST-1. A nearly complete removal of N-glycans of the recombinant C6ST-1 by peptide N-glycosidase F increased the C6ST activity but decreased the KSST activity. Among six potential N-glycosylation sites, deletion of the fourth or sixth site from the amino terminus inhibited production of the active C6ST-1, whereas deletion of the fifth site resulted in a marked loss of the KSST activity. Wild-type recombinant C6ST-1 showed a typical Golgi localization, whereas M-4 recombinant C6ST-1, in which the fourth N-glycosylation site was deleted, colocalized with calnexin, an endoplasmic reticulum-resident protein. Unlike wildtype recombinant C6ST-1, M-4 recombinant C6ST-1 showed a weak affinity toward wheat germ agglutinin and was converted completely to the nonglycosylated form by endoglycosidase H. These observations suggest that N-glycan attached to the fourth N-glycosylation site may function in the proper processing of N-glycans required for the Golgi localization, thereby causing the production of the active C6ST-1, and that N-glycan attached to the fifth N-glycosylation site may contribute to the KSST activity of C6ST-1.

  5. Fluid shear stress primes mouse embryonic stem cells for differentiation in a self-renewing environment via heparan sulfate proteoglycans transduction

    PubMed Central

    Toh, Yi-Chin; Voldman, Joel

    2011-01-01

    Shear stress is a ubiquitous environmental cue experienced by stem cells when they are being differentiated or expanded in perfusion cultures. However, its role in modulating self-renewing stem cell phenotypes is unclear, since shear is usually only studied in the context of cardiovascular differentiation. We used a multiplex microfluidic array, which overcomes the limitations of macroperfusion systems in shear application throughput and precision, to initiate a comprehensive, quantitative study of shear effects on self-renewing mouse embryonic stem cells (mESCs), where shear stresses varying by >1000 times (0.016–16 dyn/cm2) are applied simultaneously. When compared with static controls in the presence or absence of a saturated soluble environment (i.e., mESC-conditioned medium), we ascertained that flow-induced shear stress specifically up-regulates the epiblast marker Fgf5. Epiblast-state transition in mESCs involves heparan sulfate proteoglycans (HSPGs), which have also been shown to transduce shear stress in endothelial cells. By disrupting (with sulfation inhibitors and heparinase) and partially reconstituting (with heparin) HSPG function, we show that mESCs also mechanically sense shear stress via HSPGs to modulate Fgf5 expression. This study demonstrates that self-renewing mESCs possess the molecular machinery to sense shear stress and provides quantitative shear application benchmarks for future scalable stem cell culture systems.—Toh, Y.-C., Voldman, J. Fluid shear stress primes mouse embryonic stem cells for differentiation in a self-renewing environment via heparan sulfate proteoglycans transduction. PMID:21183594

  6. Immunocytochemistry of cell surface heparan sulfate proteoglycan in mouse tissues. A light and electron microscopic study.

    PubMed

    Hayashi, K; Hayashi, M; Jalkanen, M; Firestone, J H; Trelstad, R L; Bernfield, M

    1987-10-01

    The core protein of the proteoglycan at the cell surface of NMuMG mouse mammary epithelial cells bears both heparan and chondroitin sulfate chains and is recognized by the monoclonal antibody 281-2. Using this antibody and the peroxidase-antiperoxidase staining technique in adult mouse tissues, we found that the antibody recognizes the antigen in a highly restricted distribution, staining a variety of epithelial cells but no cells derived from embryonic mesoderm or neural crest. The antibody fails to stain any stromal (mesenchymal) or neuronal cells, with the exception of plasma cells and Leydig cells. Squamous and transitional epithelia stain intensely over their entire surfaces, whereas cuboidal and columnar epithelia stain moderately and only at the lateral surface of the basal cells. Within squamous and transitional epithelial tissues that undergo physiological regeneration (e.g., epidermis), the most superficial and differentiated cell types fail to stain. Within glandular and branched epithelia (e.g., pancreas), the secretory alveolar cells fail to stain. When evaluated by electron microscopy, granular deposits of stain are seen on the plasma membrane, especially on lateral surfaces, but none are noted within the cells or the basement membrane. These results indicate that in adult tissues the core protein of this heparan sulfate-rich proteoglycan is expressed almost exclusively at epithelial cell surfaces. Expression appears to be lost as the cells become either mature or highly differentiated.

  7. Acute UV irradiation increases heparan sulfate proteoglycan levels in human skin.

    PubMed

    Jung, Ji-Yong; Oh, Jang-Hee; Kim, Yeon Kyung; Shin, Mi Hee; Lee, Dayae; Chung, Jin Ho

    2012-03-01

    Glycosaminoglycans are important structural components in the skin and exist as various proteoglycan forms, except hyaluronic acid. Heparan sulfate (HS), one of the glycosaminoglycans, is composed of repeated disaccharide units, which are glucuronic acids linked to an N-acetyl-glucosamine or its sulfated forms. To investigate acute ultraviolet (UV)-induced changes of HS and HS proteoglycans (HSPGs), changes in levels of HS and several HSPGs in male human buttock skin were examined by immunohistochemistry and real-time quantitative polymerase chain reaction (qPCR) after 2 minimal erythema doses (MED) of UV irradiation (each n = 4-7). HS staining revealed that 2 MED of UV irradiation increased its expression, and staining for perlecan, syndecan-1, syndecan-4, CD44v3, and CD44 showed that UV irradiation increased their protein levels. However, analysis by real-time qPCR showed that UV irradiation did not change mRNA levels of CD44 and agrin, and decreased perlecan and syndecan-4 mRNA levels, while increased syndecan-1 mRNA level. As HS-synthesizing or -degrading enzymes, exostosin-1 and heparanase mRNA levels were increased, but exostosin-2 was decreased by UV irradiation. UV-induced matrix metalloproteinase-1 expression was confirmed for proper experimental conditions. Acute UV irradiation increases HS and HSPG levels in human skin, but their increase may not be mediated through their transcriptional regulation.

  8. Nerve Degeneration and Regeneration Associated with NF1 Tumors

    DTIC Science & Technology

    2012-06-01

    was  replaced   with  a  fibrotic  matrix  rich  in   chondroitin   sulfate  proteoglycan.       Continued  tumor  growth...the  axons  (C).    Immunolabeling  for   chondroitin   sulfate   protoeglycan  demonstrates  the  formation  of  a

  9. Chondroitin sulfates do not impede axonal regeneration in goldfish spinal cord.

    PubMed

    Takeda, Akihito; Okada, Soichiro; Funakoshi, Kengo

    2017-10-15

    Chondroitin sulfate proteoglycans produced in glial scar tissue are a major inhibitory factor for axonal regeneration after central nervous system injury in mammals. The inhibition is largely due to chondroitin sulfates, whose effects differ according to the sulfation pattern. In contrast to mammals, fish nerves spontaneously regenerate beyond the scar tissue after spinal cord injury, although the mechanisms that allow for axons to pass through the scar are unclear. Here, we used immunohistochemistry to examine the expression of two chondroitin sulfates with different sulfation variants at the lesion site in goldfish spinal cord. The intact spinal cord was immunoreactive for both chondroitin sulfate-A (CS-A) and chondroitin sulfate-C (CS-C), and CS-A immunoreactivity overlapped extensively with glial processes positive for glial fibrillary acidic protein. At 1week after inducing the spinal lesion, CS-A immunoreactivity was observed in the cell bodies and extracellular matrix, as well as in glial processes surrounding the lesion center. At 2weeks after the spinal lesion, regenerating axons entering the lesion center overtook the CS-A abundant area. In contrast, at 1week after lesion induction, CS-C immunoreactivity was significantly decreased, and at 2weeks after lesion induction, CS-C immunoreactivity was observed along the regenerating axons entering the lesion center. The present findings suggest that after spinal cord injury in goldfish, chondroitin sulfate proteoglycans are deposited in the extracellular matrix at the lesion site but do not form an impenetrable barrier to the growth of regenerating axons. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Inflammation-induced synthesis of proteoheparan sulfate: a novel acute-phase reactant in rat hepatocytes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Djovkar, A.; Gressner, A.M.

    1987-03-01

    The synthesis of proteoheparan sulfate in hepatocytes is positively regulated under acute-phase conditions produced either by turpentine or deep back incision. In both cases the incorporation of (/sup 35/S)sulfate and (/sup 14/C)glucosamine is doubled during a 4-h incubation period if compared with control rat hepatocytes. Neither the fractional secretion rate of heparan sulfate into the medium (less than 0.1 of cell-associated glycosaminoglycans) nor the composition of newly formed proteoglycans in hepatocytes are affected during acute phase reaction.

  11. Long-term Immunogenicity of Elosulfase Alfa in the Treatment of Morquio A Syndrome: Results From MOR-005, a Phase III Extension Study.

    PubMed

    Long, Brian; Tompkins, Troy; Decker, Celeste; Jesaitis, Lynne; Khan, Shahid; Slasor, Peter; Harmatz, Paul; O'Neill, Charles A; Schweighardt, Becky

    2017-01-01

    Elosulfase alfa is an enzyme replacement therapy for the treatment of Morquio A syndrome (mucopolysaccharidosis IVA), a lysosomal storage disorder caused by a deficiency of the enzyme N-acetylgalactose-amine-6-sulfatase. We previously reported immunogenicity data from our 24-week placebo-controlled Phase III study, MOR-004. Here, we report the long-term immunogenicity profile of elosulfase alfa from MOR-005, the Phase III extension trial to assess potential correlations between antidrug antibodies and efficacy and safety profile outcomes throughout 120 weeks of treatment. The long-term immunogenicity of elosulfase alfa was evaluated in patients with Morquio A syndrome in an open-label extension study for a total of 120 weeks. All patients received 2.0 mg/kg elosulfase alfa either weekly or every other week before establishment of 2.0 mg/kg/wk as the recommended dose, at which time all patients received weekly treatment. Efficacy measures were compared with those from the MOR-004 baseline, enabling analysis of changes over 120 weeks. The primary efficacy measure was the change from baseline in 6-minute walk test. Secondary measures included changes from baseline in 3-minute stair climb test and normalized urine keratan sulfate, a pharmacodynamic metric. All patients treated with elosulfase alfa developed antidrug total antibodies (TAb) by week 24 of MOR-004. In the extension study, all patients, including those who had previously received placebo, were TAb positive by study week 36 (MOR-005 week 12). All patients remained TAb positive throughout the study, and TAb titers were similar across treatment groups at week 120. Nearly all patients tested positive for neutralizing antibodies (NAb) at least once, with incidence of NAb positivity peaking at 85.9% at study week 36, then steadily declining to 66.0% at study week 120. In all treatment groups, mean urine keratan sulfate remained below treatment-naive baseline despite the presence of antidrug antibodies. No relationship was observed between TAb titers or NAb positivity and changes in urine keratan sulfate, 6-minute walk test, or 3-minute stair climb test from baseline to week 120. No consistent associations were detected between antidrug antibodies and the occurrence of hypersensitivity adverse events or anaphylaxis over the course of the study. Immunogenicity results from this long-term study are consistent with previously reported 24-week results. Despite the sustained presence of antidrug antibodies, elosulfase alfa was well tolerated, and patients continued to benefit from treatment through week 120. No associations were detected between higher TAb titers or NAb positivity and reduced treatment effect or worsened safety profile measures. ClinicalTrials.gov identifier: NCT01415427. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  12. A high molecular weight proteoglycan is differentially expressed during development of the mollusc Concholepas concholepas (Mollusca; Gastropoda; Muricidae).

    PubMed

    Brandan, E; González, M; Inestrosa, N C; Tremblay, C; Urrea, R

    1992-12-15

    Incorporation of radioactive sulfate to hatched veliger larvae of the gastropod muricid Concholepas concholepas indicated that over 87% of the sulfated macromolecules were found in the detergent insoluble fraction, rich in extracellular matrix (ECM) components. The sulfated material was solubilized with guanidine salt followed by urea dialysis and fractionated by DEAE-Sephacel chromatography. Three sulfated compounds eluting at 0.7, 1.1, and 3.0 M NaCl, called peaks I, II, and III, respectively, were obtained. The sulfated compound present in peak I was degraded by pronase or sodium alkaline treatment to a small sulfated resistant material, suggesting the presence of a proteoglycan (PG). Filtration analysis on Sephacryl S-500 and SDS-PAGE of the intact PG indicates that it has a high molecular weight (360,000 to over 1 x 10(6)). Monoclonal antibodies (mAb) against this PG were produced. The specificity of one mAb, the 6H2, was demonstrated by size chromatography and ELISA analysis. The epitope recognized by this mAb seems to be present in the core protein of the PG. Both the extent of sulfation and the presence of different sulfated species of PGs were evaluated during the development of this mollusc. A twelvefold increase in the incorporation of sulfate to PGs per milligram of protein was found in veliger larvae compared to blastula-glastula stages. This change correlated well with the differential expression of the sulfated PG present in peak I. Biochemical and immunological analysis indicate that high levels of this PG are found in veliger and trocophore larvae in comparison with blastula-gastrula and early juveniles.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. [The Role of Membrane-Bound Heat Shock Proteins Hsp90 in Migration of Tumor Cells in vitro and Involvement of Cell Surface Heparan Sulfate Proteoglycans in Protein Binding to Plasma Membrane].

    PubMed

    Snigireva, A V; Vrublevskaya, V V; Skarga, Y Y; Morenkov, O S

    2016-01-01

    Heat shock protein Hsp90, detected in the extracellular space and on the membrane of cells, plays an important role in cell motility, migration, invasion and metastasis of tumor cells. At present, the functional role and molecular mechanisms of Hsp90 binding to plasma membrane are not elucidated. Using isoform-specific antibodies against Hsp90, Hsp9α and Hsp90β, we showed that membrane-bound Hsp90α and Hsp90β play a significant role in migration of human fibrosarcoma (HT1080) and glioblastoma (A-172) cells in vitro. Disorders of sulfonation of cell heparan sulfates, cleavage of cell heparan. sulfates by heparinase I/III as well as treatment of cells with heparin lead to an abrupt reduction in the expression level of Hsp90 isoforms. Furthermore, heparin significantly inhibits tumor cell migration. The results obtained demonstrate that two isoforms of membrane-bound Hsp90 are involved in migration of tumor cells in vitro and that cell surface heparan sulfate proteoglycans play a pivotal role in the "anchoring" of Hsp90α and Hsp90β to the plasma membrane.

  14. Cerebroglycan: an integral membrane heparan sulfate proteoglycan that is unique to the developing nervous system and expressed specifically during neuronal differentiation

    PubMed Central

    1994-01-01

    Heparan sulfate proteoglycans (HSPGs) are found on the surface of all adherent cells and participate in the binding of growth factors, extracellular matrix glycoproteins, cell adhesion molecules, and proteases and antiproteases. We report here the cloning and pattern of expression of cerebroglycan, a glycosylphosphatidylinositol (GPI)- anchored HSPG that is found in the developing rat brain (previously referred to as HSPG M13; Herndon, M. E., and A. D. Lander. 1990. Neuron. 4:949-961). The cerebroglycan core protein has a predicted molecular mass of 58.6 kD and five potential heparan sulfate attachment sites. Together with glypican (David, G., V. Lories, B. Decock, P. Marynen, J.-J. Cassiman, and H. Van den Berghe. 1990. J. Cell Biol. 111:3165-3176), it defines a family of integral membrane HSPGs characterized by GPI linkage and conserved structural motifs, including a pattern of 14 cysteine residues that is absolutely conserved. Unlike other known integral membrane HSPGs, including glypican and members of the syndecan family of transmembrane proteoglycans, cerebroglycan is expressed in only one tissue: the nervous system. In situ hybridization experiments at several developmental stages strongly suggest that cerebroglycan message is widely and transiently expressed by immature neurons, appearing around the time of final mitosis and disappearing after cell migration and axon outgrowth have been completed. These results suggest that cerebroglycan may fulfill a function related to the motile behaviors of developing neurons. PMID:8294498

  15. The Glycosaminoglycans of Normal and Arthritic Cartilage

    PubMed Central

    Mankin, Henry J.; Lippiello, Louis

    1971-01-01

    The cartilages from the hip joints of 13 normal and 15 osteoarthritic humans were analyzed for glycosaminoglycan content and distribution. The GAGs were separated by elution with CPC on a short cellulose column by the technique of Svejcar and Robertson after digestion of the tissue with pronase and papain. The eluates were identified by a variety of methods including determination of molar ratios, N-acetyl-hexosamine determinations after hyaluronidase treatment and thin-layer chromatography of unhydrolyzed and hydrolyzed GAGs. From the data obtained, it was demonstrated that cartilage from arthritic patients showed a significant increase in the concentration of chondroitin 4-sulfate and a significant decrease in keratan sulfate, with only slight changes in the total amount of GAG present. Calculations of the molar ratios showed variation in the sulfation with chondroitin 4-sulfate appearing in the “supersulfated” state in the arthritic cartilage. The data lead to speculation regarding the process of osteoarthritis, and it is concluded that the changes seen are more likely to represent an altered pattern of synthesis rather than selective degradation. Since the changes suggest a younger cartilage, a theory is advanced that the chondrocyte responds to the chronic stress of osteoarthritis by modulation to a chondroblastic phase. PMID:4255496

  16. Age-related differences in human skin proteoglycans.

    PubMed

    Carrino, David A; Calabro, Anthony; Darr, Aniq B; Dours-Zimmermann, Maria T; Sandy, John D; Zimmermann, Dieter R; Sorrell, J Michael; Hascall, Vincent C; Caplan, Arnold I

    2011-02-01

    Previous work has shown that versican, decorin and a catabolic fragment of decorin, termed decorunt, are the most abundant proteoglycans in human skin. Further analysis of versican indicates that four major core protein species are present in human skin at all ages examined from fetal to adult. Two of these are identified as the V0 and V1 isoforms, with the latter predominating. The other two species are catabolic fragments of V0 and V1, which have the amino acid sequence DPEAAE as their carboxyl terminus. Although the core proteins of human skin versican show no major age-related differences, the glycosaminoglycans (GAGs) of adult skin versican are smaller in size and show differences in their sulfation pattern relative to those in fetal skin versican. In contrast to human skin versican, human skin decorin shows minimal age-related differences in its sulfation pattern, although, like versican, the GAGs of adult skin decorin are smaller than those of fetal skin decorin. Analysis of the catabolic fragments of decorin from adult skin reveals the presence of other fragments in addition to decorunt, although the core proteins of these additional decorin catabolic fragments have not been identified. Thus, versican and decorin of human skin show age-related differences, versican primarily in the size and the sulfation pattern of its GAGs and decorin in the size of its GAGs. The catabolic fragments of versican are detected at all ages examined, but appear to be in lower abundance in adult skin compared with fetal skin. In contrast, the catabolic fragments of decorin are present in adult skin, but are virtually absent from fetal skin. Taken together, these data suggest that there are age-related differences in the catabolism of proteoglycans in human skin. These age-related differences in proteoglycan patterns and catabolism may play a role in the age-related changes in the physical properties and injury response of human skin.

  17. Domain organization, genomic structure, evolution, and regulation of expression of the aggrecan gene family.

    PubMed

    Schwartz, N B; Pirok, E W; Mensch, J R; Domowicz, M S

    1999-01-01

    Proteoglycans are complex macromolecules, consisting of a polypeptide backbone to which are covalently attached one or more glycosaminoglycan chains. Molecular cloning has allowed identification of the genes encoding the core proteins of various proteoglycans, leading to a better understanding of the diversity of proteoglycan structure and function, as well as to the evolution of a classification of proteoglycans on the basis of emerging gene families that encode the different core proteins. One such family includes several proteoglycans that have been grouped with aggrecan, the large aggregating chondroitin sulfate proteoglycan of cartilage, based on a high number of sequence similarities within the N- and C-terminal domains. Thus far these proteoglycans include versican, neurocan, and brevican. It is now apparent that these proteins, as a group, are truly a gene family with shared structural motifs on the protein and nucleotide (mRNA) levels, and with nearly identical genomic organizations. Clearly a common ancestral origin is indicated for the members of the aggrecan family of proteoglycans. However, differing patterns of amplification and divergence have also occurred within certain exons across species and family members, leading to the class-characteristic protein motifs in the central carbohydrate-rich region exclusively. Thus the overall domain organization strongly suggests that sequence conservation in the terminal globular domains underlies common functions, whereas differences in the central portions of the genes account for functional specialization among the members of this gene family.

  18. Quantification of a Non-conventional Protein Secretion: The Low-Molecular-Weight FGF-2 Example.

    PubMed

    Arcondéguy, Tania; Touriol, Christian; Lacazette, Eric

    2016-01-01

    Quantification of secreted factors is most often measured with enzyme-linked immunosorbent assay (ELISA), Western Blot, or more recently with antibody arrays. However, some of these, like low-molecular-weight fibroblast growth factor-2 (LMW FGF-2; the 18 kDa form), exemplify a set of secreted but almost non-diffusible molecular actors. It has been proposed that phosphorylated FGF-2 is secreted via a non-vesicular mechanism and that heparan sulfate proteoglycans function as extracellular reservoir but also as actors for its secretion. Heparan sulfate is a linear sulfated polysaccharide present on proteoglycans found in the extracellular matrix or anchored in the plasma membrane (syndecan). Moreover the LMW FGF-2 secretion appears to be activated upon FGF-1 treatment. In order to estimate quantification of such factor export across the plasma membrane, technical approaches are presented (evaluation of LMW FGF-2: (1) secretion, (2) extracellular matrix reservoir, and (3) secretion modulation by surrounding factors) and the importance of such procedures in the comprehension of the biology of these growth factors is underlined.

  19. Compositional analysis and structural elucidation of glycosaminoglycans in chicken eggs

    PubMed Central

    Liu, Zhangguo; Zhang, Fuming; Li, Lingyun; Li, Guoyun; He, Wenqing; Linhardt, Robert J.

    2014-01-01

    Glycosaminoglycans (GAGs) have numerous applications in the fields of pharmaceuticals, cosmetics, nutraceuticals, and foods. GAGs are also critically important in the developmental biology of all multicellular animals. GAGs were isolated from chicken egg components including yolk, thick egg white, thin egg white, membrane, calcified shell matrix supernatant, and shell matrix deposit. Disaccharide compositional analysis was performed using ultra high-performance liquid chromatography-mass spectrometry. The results of these analyses showed that all four families of GAGs were detected in all egg components. Keratan sulfate was found in egg whites (thick and thin) and shell matrix (calcified shell matrix supernatant and deposit) with high level. Chondroitin sulfates were much more plentiful in both shell matrix components and membrane. Hyaluronan was plentiful in both shell matrix components and membrane, but were only present in a trace of quantities in the yolk. Heparan sulfate was plentiful in the shell matrix deposit but was present in a trace of quantities in the egg content components (yolk, thick and thin egg whites). Most of the chondroitin and heparan sulfate disaccharides were present in the GAGs found in chicken eggs with the exception of chondroitin and heparan sulfate 2,6-disulfated disaccharides. Both CS and HS in the shell matrix deposit contained the most diverse chondroitin and heparan sulfate disaccharide compositions. Eggs might provide a potential new source of GAGs. PMID:25218438

  20. The Role of Heparan Sulfate Proteoglycans in Optic Disc and Stalk Morphogenesis

    PubMed Central

    Cai, Zhigang; Grobe, Kay; Zhang, Xin

    2014-01-01

    Background Heparan sulfate proteoglycans (HSPG) are important for embryonic development via the regulation of gradient formation and signaling of multiple growth factors and morphogens. Previous studies have shown that Bmp/Shh/Fgf signaling are required for the regionalization of the optic vesicle (OV) and for the closure of the optic fissure (OF), the disturbance of which underlie ocular anomalies such as microphthalmia, coloboma and optic nerve hypoplasia. Results To study HSPG-dependent coordination of these signaling pathways during mammalian visual system development, we have generated a series of OV-specific mutations in the heparan sulfate (HS) N-sulfotransferase genes (Ndst1 and Ndst2) and HS O-sulfotransferase genes (Hs2st, Hs6st1 and Hs6st2) in mice. Interestingly, the resulting HS undersulfation still allowed for normal retinal neurogenesis and optic fissure closure, but led to defective optic disc and stalk development. The adult mutant animals further developed optic nerve aplasia/hypoplasia and displayed retinal degeneration. We observed that MAPK/ERK signaling was down-regulated in Ndst mutants, and consistent with this, HS-related optic nerve morphogenesis defects in mutant mice could partially be rescued by constitutive Kras activation. Conclusions These results suggest that HSPGs, depending on their HS sulfation pattern, regulate multiple signaling pathways in optic disc and stalk morphogenesis. PMID:24753163

  1. Carrier of Wingless (Cow), a Secreted Heparan Sulfate Proteoglycan, Promotes Extracellular Transport of Wingless

    PubMed Central

    Chang, Yung-Heng; Sun, Yi Henry

    2014-01-01

    Morphogens are signaling molecules that regulate growth and patterning during development by forming a gradient and activating different target genes at different concentrations. The extracellular distribution of morphogens is tightly regulated, with the Drosophila morphogen Wingless (Wg) relying on Dally-like (Dlp) and transcytosis for its distribution. However, in the absence of Dlp or endocytic activity, Wg can still move across cells along the apical (Ap) surface. We identified a novel secreted heparan sulfate proteoglycan (HSPG) that binds to Wg and promotes its extracellular distribution by increasing Wg mobility, which was thus named Carrier of Wg (Cow). Cow promotes the Ap transport of Wg, independent of Dlp and endocytosis, and this function addresses a previous gap in the understanding of Wg movement. This is the first example of a diffusible HSPG acting as a carrier to promote the extracellular movement of a morphogen. PMID:25360738

  2. Glycosaminoglycan Chain of Dentin Sialoprotein Proteoglycan

    PubMed Central

    Zhu, Q.; Sun, Y.; Prasad, M.; Wang, X.; Yamoah, A.K.; Li, Y.; Feng, J.; Qin, C.

    2010-01-01

    Dentin sialophosphoprotein (DSPP) is processed into dentin sialoprotein (DSP) and dentin phosphoprotein. A molecular variant of rat DSP, referred to as “HMW-DSP”, has been speculated to be a proteoglycan form of DSP. To determine if HMW-DSP is the proteoglycan form of DSP and to identify the glycosaminoglycan side-chain attachment site(s), we further characterized HMW-DSP. Chondroitinase ABC treatment reduced the migration rate for portions of rat HMW-DSP to the level of DSP. Disaccharide analysis showed that rat HMW-DSP contains glycosaminoglycan chains made of chondroitin-4-sulfate and has an average of 31-32 disaccharides/mol. These observations confirmed that HMW-DSP is the proteoglycan form of DSP (renamed “DSP-PG”). Edman degradation and mass spectrometric analyses of tryptic peptides from rat DSP-PG, along with substitution analyses of candidate Ser residues in mouse DSPP, confirmed that 2 glycosaminoglycan chains are attached to Ser241 and Ser253 in the rat, or Ser242 and Ser254 in the mouse DSPP sequence. PMID:20400719

  3. Glycosaminoglycan chain of dentin sialoprotein proteoglycan.

    PubMed

    Zhu, Q; Sun, Y; Prasad, M; Wang, X; Yamoah, A K; Li, Y; Feng, J; Qin, C

    2010-08-01

    Dentin sialophosphoprotein (DSPP) is processed into dentin sialoprotein (DSP) and dentin phosphoprotein. A molecular variant of rat DSP, referred to as "HMW-DSP", has been speculated to be a proteoglycan form of DSP. To determine if HMW-DSP is the proteoglycan form of DSP and to identify the glycosaminoglycan side-chain attachment site(s), we further characterized HMW-DSP. Chondroitinase ABC treatment reduced the migration rate for portions of rat HMW-DSP to the level of DSP. Disaccharide analysis showed that rat HMW-DSP contains glycosaminoglycan chains made of chondroitin-4-sulfate and has an average of 31-32 disaccharides/mol. These observations confirmed that HMW-DSP is the proteoglycan form of DSP (renamed "DSP-PG"). Edman degradation and mass spectrometric analyses of tryptic peptides from rat DSP-PG, along with substitution analyses of candidate Ser residues in mouse DSPP, confirmed that 2 glycosaminoglycan chains are attached to Ser(241) and Ser(253) in the rat, or Ser(242) and Ser(254) in the mouse DSPP sequence.

  4. Chondroitin-4-sulfation negatively regulates axonal guidance and growth

    PubMed Central

    Wang, Hang; Katagiri, Yasuhiro; McCann, Thomas E.; Unsworth, Edward; Goldsmith, Paul; Yu, Zu-Xi; Tan, Fei; Santiago, Lizzie; Mills, Edward M.; Wang, Yu; Symes, Aviva J.; Geller, Herbert M.

    2008-01-01

    Summary Glycosaminoglycan (GAG) side chains endow extracellular matrix proteoglycans with diversity and complexity based upon the length, composition, and charge distribution of the polysaccharide chain. Using cultured primary neurons, we show that specific sulfation in the GAG chains of chondroitin sulfate (CS) mediates neuronal guidance cues and axonal growth inhibition. Chondroitin-4-sulfate (CS-A), but not chondroitin-6-sulfate (CS-C), exhibits a strong negative guidance cue to mouse cerebellar granule neurons. Enzymatic and gene-based manipulations of 4-sulfation in the GAG side chains alter their ability to direct growing axons. Furthermore, 4-sulfated CS GAG chains are rapidly and significantly increased in regions that do not support axonal regeneration proximal to spinal cord lesions in mice. Thus, our findings provide the evidence showing that specific sulfation along the carbohydrate backbone carries instructions to regulate neuronal function. PMID:18768934

  5. Rosmarinic acid induces rabbit articular chondrocyte differentiation by decreases matrix metalloproteinase-13 and inflammation by upregulating cyclooxygenase-2 expression.

    PubMed

    Eo, Seong-Hui; Kim, Song Ja

    2017-09-18

    Matrix metalloproteinases (MMPs) are known to play an important role in the degradation of the extracellular matrix and the pathological progression of osteoarthritis (OA). The natural polyphenolic compound rosmarinic acid (Ros. A) has been shown to suppress the inhibitory activity of matrix metalloproteinases (MMPs). However, the effects of Ros. A on OA have not been investigated. In the current study, primary articular chondrocytes were cultured from rabbit articular cartilage and treated with Ros. A. Phenotypic characterization was performed by western blotting to assess specific markers, prostaglandin E 2 (PGE 2 ) assays, and alcian blue staining to measure sulfated-proteoglycan production. We report that in rabbit articular chondrocytes, Ros. A increased type II collagen, sulfated-proteoglycan, cyclooxygenase-2 (COX-2), and PGE 2 production in a dose- and time-dependent manner. Furthermore, Ros. A suppressed the expression of MMP-13. In addition, treatment with Ros A activated extracellular signal-regulated kinase (ERK)-1/2 and p38 kinase signaling pathways. Inhibition of MMP-13 enhanced Ros. A-induced type II collagen expression and sulfated-proteoglycan synthesis but COX-2 and PGE 2 production were unchanged. Ros. A-mediated up-regulation of ERK phosphorylation was abolished by the MEK inhibitor, PD98059, which prevented induction of the associated inflammatory response. Inhibition of p38 kinase with SB203580 enhanced the increase in type II collagen expression via Ros. A-mediated down-regulation of MMP-13. Results suggest that ERK-1/2 regulates Ros. A-induced inflammation and that p38 regulates differentiation by inhibiting MMP-13 in rabbit articular chondrocytes.

  6. Elevation of glycosaminoglycans in the amniotic fluid of a fetus with mucopolysaccharidosis VII

    PubMed Central

    Kubaski, Francyne; Brusius-Facchin, Ana Carolina; Mason, Robert W.; Patel, Pravin; Burin, Maira G.; Michelin-Tirelli, Kristiane; Kessler, Rejane Gus; Bender, Fernanda; Leistner-Segal, Sandra; Moreno, Carolina A.; Cavalcanti, Denise P.; Giugliani, Roberto; Tomatsu, Shunji

    2017-01-01

    Objective The aim of this study was to quantify GAGs in amniotic fluid (AF) from an MPS VII fetus compared with age-matched fetuses obtained from normal pregnancies. Method Disaccharides were measured by liquid chromatography tandem mass spectrometry (LC/MS/MS), compared to age-matched controls. Enzyme assay was performed in AF supernatant or cultured amniocytes. GUSB was analyzed by next generation sequencing using Ion Torrent Personal Genome Machine with a customized panel. Results No activity of β-glucuronidase was detected in fetal cells. The pregnancy was spontaneously terminated in the third trimester. Genetic studies identified a homozygous mutation of p.N379D (c.1135A>G) in the GUSB gene. LC/MS/MS showed that chondroitin sulfate, dermatan sulfate, heparan sulfate, and keratan sulfate levels were markedly increased in the MPS VII AF, compared to those in age-matched control AF (DS, HS, and C6S more than 10 × than age-matched controls; C4S and KS more than 3 times higher). Conclusion This is the first report of specific GAG analysis in AF from an MPS VII fetus, indicating that GAG elevation in AF occurs by 21 weeks of gestation and could be an additional tool for prenatal diagnosis of MPS VII and potentially other MPS types. PMID:28207930

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ecarot-Charrier, B.; Bouchard, F.; Delloye, C.

    Isolated mouse osteoblasts that retain their osteogenic activity in culture were incubated with (35S) sulfate. Two radiolabeled proteins, in addition to proteoglycans, were extracted from the calcified matrix of osteoblast cultures. All the sulfate label in both proteins was in the form of tyrosine sulfate as assessed by amino acid analysis and thin layer chromatography following alkaline hydrolysis. The elution behavior on DEAE-Sephacel of the major sulfated protein and the apparent Mr on sodium dodecyl sulfate gels were characteristic of bone sialoprotein II extracted from rat. This protein was shown to cross-react with an antiserum raised against bovine bone sialoproteinmore » II, indicating that bone sialoprotein II synthesized by cultured mouse osteoblasts is a tyrosine-sulfated protein. The minor sulfated protein was tentatively identified as bone sialoprotein I or osteopontin based on its elution properties on DEAE-Sephacel and anomalous behavior on sodium dodecyl sulfate gels similar to those reported for rat bone sialoprotein I.« less

  8. Do chondroitin sulfates with different structures have different activities on chondrocytes and macrophages?

    PubMed

    da Cunha, André L; Aguiar, Jair A K; Correa da Silva, Flavio S; Michelacci, Yara M

    2017-10-01

    The aim of the present study was to investigate the activities of natural chondroitin sulfates (CS) with different structures on cultured chondrocytes and macrophages. CS were isolated from cartilages of bovine trachea (BT), porcine trachea (PT), chicken sternum (Ch) and skate (Sk). The preparations were 90-98% pure, with ∼1% proteins, nucleic acids and keratan sulfate contaminants. Structural analysis of these CS and of commercial chondroitin 4- and 6-sulfate (C4S, C6S) have shown that most of their disaccharides are monosulfated, with varying proportions of 4- and 6-sulfation, and 2-7% non-sulfated disaccharides. Sk-CS and C6S contained detectable amounts of disulfated disaccharides. All the CS were polydisperse, with modal molecular weights of 26-135kDa. These CS had anti-inflammatory activities on both chondrocytes and macrophages, but with different efficiencies. On horse and human chondrocytes, they reduced the IL-1β-induced liberation of NO and PGE 2 , and on RAW 264.7 immortalized macrophage-like cell line, C4S, C6S, Ch and Sk-CS decreased the LPS-induced liberation of TNF-α, but did not affect IL-6. In contrast, on bone marrow derived macrophages, C4S, C6S, BT and PT-CS reduced the LPS-induced liberation of TNF-α, IL-6, IL-1β and NO, indicating that the RAW response to CS was different from that of primary macrophages. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Caenorhabditis elegans syndecan (SDN-1) is required for normal egg laying and associates with the nervous system and the vulva.

    PubMed

    Minniti, Alicia N; Labarca, Mariana; Hurtado, Claudia; Brandan, Enrique

    2004-10-01

    In Caenorhabditis elegans, the identification of many enzymes involved in the synthesis and modification of glycosaminoglycans (GAGs), essential components of proteoglycans, has attained special attention in recent years. Mutations in all the genes that encode for GAG biosynthetic enzymes show defects in the development of the vulva, specifically in the invagination of the vulval epithelium. Mutants for certain heparan sulfate modifying enzymes present axonal and cellular guidance defects in specific neuronal classes. Although most of the enzymes involved in the biosynthesis and modification of heparan sulfate have been characterized in C. elegans, little is known regarding the core proteins to which these GAGs covalently bind in proteoglycans. A single syndecan homologue (sdn-1) has been identified in the C. elegans genome through sequence analysis. In the present study, we show that C. elegans synthesizes sulfated proteoglycans, seen as three distinct species in western blot analysis. In the sdn-1 (ok449) deletion mutant allele we observed the lack of one species, which corresponds to a 50 kDa product after heparitinase treatment. The expression of sdn-1 mRNA and sequencing revealed that sdn-1 (ok449) deletion mutants lack two glycosylation sites. Hence, the missing protein in the western blot analysis probably corresponds to SDN-1. In addition, we show that SDN-1 localizes to the C. elegans nerve ring, nerve cords and to the vulva. SDN-1 is found specifically phosphorylated in nerve ring neurons and in the vulva, in both wild-type worms and sdn-1 (ok449) deletion mutants. These mutants show a defective egg-laying phenotype. Our results show for the first time, the identification, localization and some functional aspects of syndecan in the nematode C. elegans.

  10. Impaired proteoglycan glycosylation, elevated TGF-β signaling, and abnormal osteoblast differentiation as the basis for bone fragility in a mouse model for gerodermia osteodysplastica

    PubMed Central

    Chan, Wing Lee; Steiner, Magdalena; Egerer, Johannes; Mizumoto, Shuji; Pestka, Jan M.; Zhang, Haikuo; Khayal, Layal Abo; Ott, Claus-Eric; Kolanczyk, Mateusz; Schinke, Thorsten; Paganini, Chiara; Rossi, Antonio; Sugahara, Kazuyuki; Amling, Michael; Knaus, Petra; Chan, Danny; Mundlos, Stefan

    2018-01-01

    Gerodermia osteodysplastica (GO) is characterized by skin laxity and early-onset osteoporosis. GORAB, the responsible disease gene, encodes a small Golgi protein of poorly characterized function. To circumvent neonatal lethality of the GorabNull full knockout, Gorab was conditionally inactivated in mesenchymal progenitor cells (Prx1-cre), pre-osteoblasts (Runx2-cre), and late osteoblasts/osteocytes (Dmp1-cre), respectively. While in all three lines a reduction in trabecular bone density was evident, only GorabPrx1 and GorabRunx2 mutants showed dramatically thinned, porous cortical bone and spontaneous fractures. Collagen fibrils in the skin of GorabNull mutants and in bone of GorabPrx1 mutants were disorganized, which was also seen in a bone biopsy from a GO patient. Measurement of glycosaminoglycan contents revealed a reduction of dermatan sulfate levels in skin and cartilage from GorabNull mutants. In bone from GorabPrx1 mutants total glycosaminoglycan levels and the relative percentage of dermatan sulfate were both strongly diminished. Accordingly, the proteoglycans biglycan and decorin showed reduced glycanation. Also in cultured GORAB-deficient fibroblasts reduced decorin glycanation was evident. The Golgi compartment of these cells showed an accumulation of decorin, but reduced signals for dermatan sulfate. Moreover, we found elevated activation of TGF-β in GorabPrx1 bone tissue leading to enhanced downstream signalling, which was reproduced in GORAB-deficient fibroblasts. Our data suggest that the loss of Gorab primarily perturbs pre-osteoblasts. GO may be regarded as a congenital disorder of glycosylation affecting proteoglycan synthesis due to delayed transport and impaired posttranslational modification in the Golgi compartment. PMID:29561836

  11. High resolution immunoelectron microscopic localization of functional domains of laminin, nidogen, and heparan sulfate proteoglycan in epithelial basement membrane of mouse cornea reveals different topological orientations.

    PubMed

    Schittny, J C; Timpl, R; Engel, J

    1988-10-01

    Thin and ultrathin cryosections of mouse cornea were labeled with affinity-purified antibodies directed against either laminin, its central segments (domain 1), the end of its long arm (domain 3), the end of one of its short arms (domain 4), nidogen, or low density heparan sulfate proteoglycan. All basement membrane proteins are detected by indirect immunofluorescence exclusively in the epithelial basement membrane, in Descemet's membrane, and in small amorphous plaques located in the stroma. Immunoelectron microscopy using the protein A-gold technique demonstrated laminin domain 1 and nidogen in a narrow segment of the lamina densa at the junction to the lamina lucida within the epithelial basement membrane. Domain 3 shows three preferred locations at both the cellular and stromal boundaries of the epithelial basement membrane and in its center. Domain 4 is located predominantly in the lamina lucida and the adjacent half of the lamina densa. The low density heparan sulfate proteoglycan is found all across the basement membrane showing a similar uniform distribution as with antibodies against the whole laminin molecule. In Descemet's membrane an even distribution was found with all these antibodies. It is concluded that within the epithelial basement membrane the center of the laminin molecule is located near the lamina densa/lamina lucida junction and that its long arm favors three major orientations. One is close to the cell surface indicating binding to a cell receptor, while the other two are directed to internal matrix structures. The apparent codistribution of laminin domain 1 and nidogen agrees with biochemical evidence that nidogen binds to this domain.

  12. Astrocytes Specifically Remove Surface-Adsorbed Fibrinogen and Locally Express Chondroitin Sulfate Proteoglycans

    PubMed Central

    Hsiao, Tony W.; Swarup, Vimal P.; Kuberan, Balagurunathan; Tresco, Patrick A.; Hlady, Vladimir

    2013-01-01

    Surface-adsorbed fibrinogen (FBG) was recognized by adhering astrocytes and removed from the substrates in vitro by a two-phase removal process. The cells removed adsorbed FBG from binary proteins surface patterns (FBG + laminin, or FBG + albumin) while leaving the other protein behind. Astrocytes preferentially expressed chondroitin sulfate proteoglycan (CSPG) at the loci of fibrinogen stimuli; however no differences in overall CSPG production as a function of FBG surface coverage were identified. Removal of FBG by astrocytes was also found to be independent of transforming growth factor type β (TGF-β) receptor based signaling as cells maintained CSPG production in the presence of TGF-β receptor kinase inhibitor, SB 431542. The inhibitor decreased CSPG expression, but did not abolicsh it entirely. Because blood contact and subsequent FBG adsorption are unavoidable in neural implantations, the results indicate that implant-adsorbed FBG may contribute to reactive astrogliosis around the implant as astrocytes specifically recognize adsorbed FBG. PMID:23499985

  13. Distinct Secondary Structures of the Leucine-Rich Repeat Proteoglycans Decorin and Biglycan: Glycosylation-Dependent Conformational Stability

    NASA Technical Reports Server (NTRS)

    Krishnan, Priya; Hocking, Anne M.; Scholtz, J. Martin; Pace, C. Nick; Holik, Kimberly K.; McQuillan, David J.

    1998-01-01

    Biglycan and decorin, closely related small leucine-rich repeat proteoglycans, have been overexpressed in eukaryotic cers and two major glycoforms isolated under native conditions: a proteoglycan substituted with glycosaminoglycan chains; and a core protein form secreted devoid of glycosaminoglycans. A comparative biophysical study of these glycoforms has revealed that the overall secondary structures of biglycan and decorin are different. Far-UV Circular Dichroism (CD) spectroscopy of decorin and biglycan proteoglycans indicates that, although they are predominantly Beta-sheet, biglycan has a significantly higher content of alpha-helical structure. Decorin proteoglycan and core protein are very similar, whereas the biglycan core protein exhibits closer similarity to the decorin glycoforms than to. the biglycan proteoglycan form. However, enzymatic removal of the chondroitin sulfate chains from biglycan proteoglycan does not induce a shift to the core protein structure, suggesting that the fmal form is influenced by polysaccharide addition only during biosynthesis. Fluorescence emission spectroscopy demonstrated that the single tryptophan residue, which is at a conserved position at the C-terminal domain of both biglycan and decorin, is found in similar microenvironments. This indicates that at least in this specific domain, the different glycoforms do exhibit apparent conservation of structure. Exposure of decorin and biglycan to 10 M urea resulted in an increase in fluorescent intensity, which indicates that the emission from tryptophan in the native state is quenched. Comparison of urea-induced protein unfolding curves provided further evidence that decorin and biglycan assume different structures in solution. Decorin proteoglycan and core protein unfold in a manner similar to a classic two-state model, in which there is a steep transition to an unfolded state between 1-2 M urea. The biglycan core protein also shows a similar steep transition. However, biglycan proteoglycan shows a broad unfolding transition between 1-6 M urea, probably indicating the presence of stable unfolding intermediates.

  14. The structure of interfibrillar proteoglycan bridges (‘shape modules’) in extracellular matrix of fibrous connective tissues and their stability in various chemical environments

    PubMed Central

    SCOTT, JOHN E.; THOMLINSON, ALISON M.

    1998-01-01

    Collagen fibrils in extracellular matrices of connective tissues (tendon, cornea, etc.) are bridged and linked by the anionic glycosaminoglycans (AGAGs) of the small proteoglycans (decoron, etc.). It was proposed that these bridges and ties maintain the collagen fibril dispositions in relation to each other, helping to define tissue shape, and hence called shape modules. This investigation describes chemical and physicochemical conditions in which these structures are stable and what treatments cause their disruption. The effects on fixed and unfixed sections of tendon, cornea, lung and ear from rat, mouse and rabbit of pH, electrolyte concentration, EDTA, mercaptoethanol, hydrogen peroxide, free radicals, periodate, acetylation, urea, nonionic detergent and organic solvents were assessed by staining with Cupromeronic blue or Alcec blue in CEC techniques to localise AGAG bridges or their disintegration products. Ca2+ was not involved in the structures, oxidation/reduction had no effect and Triton X100, a nonionic detergent did not damage them. They were stable between pH 4.5 and 9.5. Periodate as a glycol-cleaving reagent did not affect them. High concentrations of urea (>2.0 m) and MgCl2 (0.5 m) disrupted the tissues. The combination of Triton and urea at concentrations too low to cause damage separately was disruptive. Free radicals in periodate solutions were damaging. Organic solvents caused collapse and rearrangements of the AGAG filaments. Acetylation caused considerable disruption of shape modules. Dermochondan but not keratan sulphate AGAGs were removed by treatment with NaOH. After fixing with glutaraldehyde only free radical and NaOH treatments were severely disruptive of shape modules. The results are compatible with a previously proposed structure for the shape modules, stabilised by hydrophobic and hydrogen bonding. PMID:9688505

  15. Functional Requirements for Heparan Sulfate Biosynthesis in Morphogenesis and Nervous System Development in C. elegans.

    PubMed

    Blanchette, Cassandra R; Thackeray, Andrea; Perrat, Paola N; Hekimi, Siegfried; Bénard, Claire Y

    2017-01-01

    The regulation of cell migration is essential to animal development and physiology. Heparan sulfate proteoglycans shape the interactions of morphogens and guidance cues with their respective receptors to elicit appropriate cellular responses. Heparan sulfate proteoglycans consist of a protein core with attached heparan sulfate glycosaminoglycan chains, which are synthesized by glycosyltransferases of the exostosin (EXT) family. Abnormal HS chain synthesis results in pleiotropic consequences, including abnormal development and tumor formation. In humans, mutations in either of the exostosin genes EXT1 and EXT2 lead to osteosarcomas or multiple exostoses. Complete loss of any of the exostosin glycosyltransferases in mouse, fish, flies and worms leads to drastic morphogenetic defects and embryonic lethality. Here we identify and study previously unavailable viable hypomorphic mutations in the two C. elegans exostosin glycosyltransferases genes, rib-1 and rib-2. These partial loss-of-function mutations lead to a severe reduction of HS levels and result in profound but specific developmental defects, including abnormal cell and axonal migrations. We find that the expression pattern of the HS copolymerase is dynamic during embryonic and larval morphogenesis, and is sustained throughout life in specific cell types, consistent with HSPGs playing both developmental and post-developmental roles. Cell-type specific expression of the HS copolymerase shows that HS elongation is required in both the migrating neuron and neighboring cells to coordinate migration guidance. Our findings provide insights into general principles underlying HSPG function in development.

  16. Human Metapneumovirus (HMPV) Binding and Infection Are Mediated by Interactions between the HMPV Fusion Protein and Heparan Sulfate

    PubMed Central

    Chang, Andres; Masante, Cyril; Buchholz, Ursula J.

    2012-01-01

    Human metapneumovirus (HMPV) is a major worldwide respiratory pathogen that causes acute upper and lower respiratory tract disease. The mechanism by which this virus recognizes and gains access to its target cell is still largely unknown. In this study, we addressed the initial steps in virus binding and infection and found that the first binding partner for HMPV is heparan sulfate (HS). While wild-type CHO-K1 cells are permissive to HMPV infection, mutant cell lines lacking the ability to synthesize glycosaminoglycans (GAGs), specifically, heparan sulfate proteoglycans (HSPGs), were resistant to binding and infection by HMPV. The permissiveness to HMPV infection was also abolished when CHO-K1 cells were treated with heparinases. Importantly, using recombinant HMPV lacking both the G and small hydrophobic (SH) proteins, we report that this first virus-cell binding interaction is driven primarily by the fusion protein (HMPV F) and that this interaction is needed to establish a productive infection. Finally, HMPV binding to cells did not require β1 integrin expression, and RGD-mediated interactions were not essential in promoting HMPV F-mediated cell-to-cell membrane fusion. Cells lacking β1 integrin, however, were less permissive to HMPV infection, indicating that while β1 integrins play an important role in promoting HMPV infection, the interaction between integrins and HMPV occurs after the initial binding of HMPV F to heparan sulfate proteoglycans. PMID:22238303

  17. Conditioning of native substrates by chondroitin sulfate proteoglycans during cardiac mesenchymal cell migration

    PubMed Central

    1986-01-01

    It is generally proposed that embryonic mesenchymal cells use sulfated macromolecules during in situ migration. Attempts to resolve the molecular mechanisms for this hypothesis using planar substrates have been met with limited success. In the present study, we provide evidence that the functional significance of certain sulfated macromolecules during mesenchyme migration required the presence of the endogenous migratory template; i.e., native collagen fibrils. Using three-dimensional collagen gel lattices and whole embryo culture procedures to produce metabolically labeled sulfated macromolecules in embryonic chick cardiac tissue, we show that these molecules were primarily proteoglycan (PG) in nature and that their distribution was class specific; i.e., heparan sulfate PG, the minor labeled component (15%), remained pericellular while chondroitin sulfate (CS) PG, the predominately labeled PG (85%), was associated with collagen fibrils as "trails" of 50-60-nm particles when viewed by scanning electron microscopy. Progressive "conditioning" of collagen with CS-PG inhibited the capacity of the template to support subsequent cell migration. Lastly, metabolically labeled, PG-derived CS chains were compared with respect to degree of sulfation in either the C-6 or C-4 position by chromatographic separation of chondroitinase AC digestion products. Results from temporal and regional comparisons of in situ-labeled PGs indicated a positive correlation between the presence of mesenchyme and an enrichment of disaccharide-4S relative to that from regions lacking mesenchyme (i.e., principally myocardial tissue). The suggestion of a mesenchyme-specific CS-PG was substantiated by similarly examining the PGs synthesized solely by cardiac mesenchymal cells migrating within hydrated collagen lattice in culture. These data were incorporated into a model of "substratum conditioning" which provides a molecular mechanism by which secretion of mesenchyme-specific CS-PGs not only provides for directed and sustained cell movement, but ultimately inhibits migration of the cell population as a whole. PMID:3782305

  18. Antibody recognizing 4-sulfated chondroitin sulfate proteoglycans restores memory in tauopathy-induced neurodegeneration.

    PubMed

    Yang, Sujeong; Hilton, Sam; Alves, João Nuno; Saksida, Lisa M; Bussey, Timothy; Matthews, Russell T; Kitagawa, Hiroshi; Spillantini, Maria Grazia; Kwok, Jessica C F; Fawcett, James W

    2017-11-01

    Chondroitin sulfate proteoglycans (CSPGs) are the main active component of perineuronal nets (PNNs). Digestion of the glycosaminoglycan chains of CSPGs with chondroitinase ABC or transgenic attenuation of PNNs leads to prolongation of object recognition memory and activation of various forms of plasticity in the adult central nervous system. The inhibitory properties of the CSPGs depend on the pattern of sulfation of their glycosaminoglycans, with chondroitin 4-sulfate (C4S) being the most inhibitory form. In this study, we tested a number of candidates for functional blocking of C4S, leading to selection of an antibody, Cat316, which specifically recognizes C4S and blocks its inhibitory effects on axon growth. It also partly blocks binding of semaphorin 3A to PNNs and attenuates PNN formation. We asked whether injection of Cat316 into the perirhinal cortex would have the same effects on memory as chondroitinase ABC treatment. We found that masking C4S with the Cat316 antibody extended long-term object recognition memory in normal wild-type mice to 24 hours, similarly to chondroitinase or transgenic PNN attenuation. We then tested Cat316 for restoration of memory in a neurodegeneration model. Mice expressing tau with the P301S mutation showed profound loss of object recognition memory at 4 months of age. Injection of Cat316 into the perirhinal cortex normalized object recognition at 3 hours in P301S mice. These data indicate that Cat316 binding to C4S in the extracellular matrix can restore plasticity and memory in the same way as chondroitinase ABC digestion. Our results suggest that antibodies to C4S could be a useful therapeutic to restore memory function in neurodegenerative disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Transforming growth factor-β2 is sequestered in preterm human milk by chondroitin sulfate proteoglycans

    PubMed Central

    Namachivayam, Kopperuncholan; Coffing, Hayley P.; Sankaranarayanan, Nehru Viji; Jin, Yingzi; MohanKumar, Krishnan; Frost, Brandy L.; Blanco, Cynthia L.; Patel, Aloka L.; Meier, Paula P.; Garzon, Steven A.; Desai, Umesh R.

    2015-01-01

    Human milk contains biologically important amounts of transforming growth factor-β2 isoform (TGF-β2), which is presumed to protect against inflammatory gut mucosal injury in the neonate. In preclinical models, enterally administered TGF-β2 can protect against experimental necrotizing enterocolitis, an inflammatory bowel necrosis of premature infants. In this study, we investigated whether TGF-β bioactivity in human preterm milk could be enhanced for therapeutic purposes by adding recombinant TGF-β2 (rTGF-β2) to milk prior to feeding. Milk-borne TGF-β bioactivity was measured by established luciferase reporter assays. Molecular interactions of TGF-β2 were investigated by nondenaturing gel electrophoresis and immunoblots, computational molecular modeling, and affinity capillary electrophoresis. Addition of rTGF-β2 (20–40 nM) to human preterm milk samples failed to increase TGF-β bioactivity in milk. Milk-borne TGF-β2 was bound to chondroitin sulfate (CS) containing proteoglycan(s) such as biglycan, which are expressed in high concentrations in milk. Chondroitinase treatment of milk increased the bioactivity of both endogenous and rTGF-β2, and consequently, enhanced the ability of preterm milk to suppress LPS-induced NF-κB activation in macrophages. These findings provide a mechanism for the normally low bioavailability of milk-borne TGF-β2 and identify chondroitinase digestion of milk as a potential therapeutic strategy to enhance the anti-inflammatory effects of preterm milk. PMID:26045614

  20. HB-EGF function in cardiac valve development requires interaction with heparan sulfate proteoglycans.

    PubMed

    Iwamoto, Ryo; Mine, Naoki; Kawaguchi, Taichiro; Minami, Seigo; Saeki, Kazuko; Mekada, Eisuke

    2010-07-01

    HB-EGF, a member of the EGF family of growth factors, plays an important role in cardiac valve development by suppressing mesenchymal cell proliferation. Here, we show that HB-EGF must interact with heparan sulfate proteoglycans (HSPGs) to properly function in this process. In developing valves, HB-EGF is synthesized in endocardial cells but accumulates in the mesenchyme by interacting with HSPGs. Disrupting the interaction between HB-EGF and HSPGs in an ex vivo model of endocardial cushion explants resulted in increased mesenchymal cell proliferation. Moreover, homozygous knock-in mice (HB(Delta)(hb/)(Delta)(hb)) expressing a mutant HB-EGF that cannot bind to HSPGs developed enlarged cardiac valves with hyperproliferation of mesenchymal cells; this resulted in a phenotype that resembled that of Hbegf-null mice. Interestingly, although Hbegf-null mice had abnormal heart chambers and lung alveoli, HB(Delta)(hb/)(Delta)(hb) mice did not exhibit these defects. These results indicate that interactions with HSPGs are essential for the function of HB-EGF, especially in cardiac valve development, in which HB-EGF suppresses mesenchymal cell proliferation.

  1. Structural Aspects of N-Glycosylations and the C-terminal Region in Human Glypican-1*

    PubMed Central

    Awad, Wael; Adamczyk, Barbara; Örnros, Jessica; Karlsson, Niclas G.; Mani, Katrin; Logan, Derek T.

    2015-01-01

    Glypicans are multifunctional cell surface proteoglycans involved in several important cellular signaling pathways. Glypican-1 (Gpc1) is the predominant heparan sulfate proteoglycan in the developing and adult human brain. The two N-linked glycans and the C-terminal domain that attach the core protein to the cell membrane are not resolved in the Gpc1 crystal structure. Therefore, we have studied Gpc1 using crystallography, small angle x-ray scattering, and chromatographic approaches to elucidate the composition, structure, and function of the N-glycans and the C terminus and also the topology of Gpc1 with respect to the membrane. The C terminus is shown to be highly flexible in solution, but it orients the core protein transverse to the membrane, directing a surface evolutionarily conserved in Gpc1 orthologs toward the membrane, where it may interact with signaling molecules and/or membrane receptors on the cell surface, or even the enzymes involved in heparan sulfate substitution in the Golgi apparatus. Furthermore, the N-glycans are shown to extend the protein stability and lifetime by protection against proteolysis and aggregation. PMID:26203194

  2. A chondrodysplasia family produced by mutations in the diastrophic dysplasia sulfate transporter gene: Genotype/phenotype correlations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Superti-Furga, A.; Steinmann, B.; Gitzelmann, R.

    1996-05-03

    Achondrogenesis type 1B (ACG-1B), atelosteogenesis type 2 (AO-2), and diastrophic dysplasia (DTD) are recessively inherited chondrodysplasia of decreasing severity caused by mutations in the diastrophic dysplasia sulfate transporter (DTDST) gene on chromosome 5. In these conditions, sulfate transport across the cell membrane is impaired which results in insufficient sulfation of cartilage proteoglycans and thus in an abnormally low sulfate content of cartilage. The severity of the phenotype correlates well with the predicted effect of the underlying DTDST mutations: homozygosity or compound heterozygosity for stop codons or transmembrane domain substitutions mostly result in achondrogenesis type 1B, while other structural or regulatorymore » mutations usually result in one of the less severe phenotypes. The chondrodysplasia arising at the DTDST locus constitute a bone dysplasia family with recessive inheritance. 28 refs., 2 tabs.« less

  3. Modification of P-selectin glycoprotein ligand-1 with a natural killer cell-restricted sulfated lactosamine creates an alternate ligand for L-selectin

    PubMed Central

    André, Pascale; Spertini, Olivier; Guia, Sophie; Rihet, Pascal; Dignat-George, Françoise; Brailly, Hervé; Sampol, José; Anderson, Paul J.; Vivier, Eric

    2000-01-01

    Natural killer (NK) cells are components of the innate immune system that can recognize and kill virally infected cells, tumor cells, and allogeneic cells without prior sensitization. NK cells also elaborate cytokines (e.g., interferon-γ and tumor necrosis factor-α) and chemokines (e.g., macrophage inflammatory protein-1α) that promote the acquisition of antigen-specific immunity. NK cell differentiation is accompanied by the cell surface expression of a mucin-like glycoprotein bearing an NK cell-restricted keratan sulfate-related lactosamine carbohydrate, the PEN5 epitope. Here, we report that PEN5 is a post-translational modification of P-selectin glycoprotein ligand-1 (PSGL-1). The PEN5 epitope creates on PSGL-1 a unique binding site for L-selectin, which is independent of PSGL-1 tyrosine sulfation. On the surface of NK cells, the expression of PEN5 is coordinated with the disappearance of L-selectin and the up-regulation of Killer cell Ig-like Receptors (KIR). These results indicate that NK cell differentiation is accompanied by the acquisition of a unique carbohydrate, PEN5, that can serve as part of a combination code to deliver KIR+ NK cells to specific tissues. PMID:10725346

  4. Mucopolysaccharidosis IVA and glycosaminoglycans

    PubMed Central

    Khan, Shaukat; Alméciga-Díaz, Carlos J.; Sawamoto, Kazuki; Mackenzie, William G.; Theroux, Mary C; Pizarro, Christian; Mason, Robert W.; Orii, Tadao; Tomatsu, Shunji

    2016-01-01

    Mucopolysaccharidosis IVA (MPS IVA; Morquio A: OMIM 253000) is a lysosomal storage disease with an autosomal recessive trait caused by the deficiency of N-acetylgalactosamine-6-sulfate sulfatase. Deficiency of this enzyme leads to accumulation of specific glycosaminoglycans (GAGs): chondroitin-6-sulfate (C6S) and keratan sulfate (KS). C6S and KS are mainly produced in the cartilage. Therefore, the undegraded substrates are stored primarily in cartilage and in its extracellular matrix (ECM), leading to a direct impact on cartilage and bone development, and successive systemic skeletal dysplasia. Chondrogenesis, the earliest phase of skeletal formation, is maintained by cellular interactions with the ECM, growth and differentiation factors, signaling pathways, and transcription factors in a temporal-spatial manner. In patients with MPS IVA, the cartilage is disrupted at birth as a consequence of abnormal chondrogenesis and/or endochondral ossification. The unique skeletal features are distinguished by a disproportional short stature, odontoid hypoplasia, spinal cord compression, tracheal obstruction, pectus carinatum, kyphoscoliosis, platyspondyly, coxa valga, genu valgum, waddling gait, and laxity of joints. In spite of many descriptions of these unique clinical features, delay of diagnosis still happens. The pathogenesis and treatment of systemic skeletal dysplasia in MPS IVA remains an unmet challenge. In this review article, we comprehensively describe historical aspect, property of GAGs, diagnosis, screening, pathogenesis, and current and future therapies of MPS IVA. PMID:27979613

  5. A comparison of glycosaminoglycan distributions, keratan sulphate sulphation patterns and collagen fibril architecture from central to peripheral regions of the bovine cornea

    PubMed Central

    Ho, Leona T.Y.; Harris, Anthony M.; Tanioka, Hidetoshi; Yagi, Naoto; Kinoshita, Shigeru; Caterson, Bruce; Quantock, Andrew J.; Young, Robert D.; Meek, Keith M.

    2014-01-01

    This study investigated changes in collagen fibril architecture and the sulphation status of keratan sulphate (KS) glycosaminoglycan (GAG) epitopes from central to peripheral corneal regions. Freshly excised adult bovine corneal tissue was examined as a function of radial position from the centre of the cornea outwards. Corneal thickness, tissue hydration, hydroxyproline content, and the total amount of sulphated GAG were all measured. High and low-sulphated epitopes of keratan sulphate were studied by immunohistochemistry and quantified by ELISA. Chondroitin sulphate (CS) and dermatan sulphate (DS) distributions were observed by immunohistochemistry following specific enzyme digestions. Electron microscopy and X-ray fibre diffraction were used to ascertain collagen fibril architecture. The bovine cornea was 1021 ± 5.42 μm thick at its outer periphery, defined as 9–12 mm from the corneal centre, compared to 844 ± 8.10 μm at the centre. The outer periphery of the cornea was marginally, but not significantly, more hydrated than the centre (H = 4.3 vs. H = 3.7), and was more abundant in hydroxyproline (0.12 vs. 0.06 mg/mg dry weight of cornea). DMMB assays indicated no change in the total amount of sulphated GAG across the cornea. Immunohistochemistry revealed the presence of both high- and low-sulphated epitopes of KS, as well as DS, throughout the cornea, and CS only in the peripheral cornea before the limbus. Quantification by ELISA, disclosed that although both high- and low-sulphated KS remained constant throughout stromal depth at different radial positions, high-sulphated epitopes remained constant from the corneal centre to outer-periphery, whereas low-sulphated epitopes increased significantly. Both small angle X-ray diffraction and TEM analysis revealed that collagen fibril diameter remained relatively constant until the outer periphery was reached, after which fibrils became more widely spaced (from small angle x-ray diffraction analysis) and of larger diameter as they approached the sclera. Depth-profiled synchrotron microbeam analyses showed that, at different radial positions from the corneal centre outwards, fibril diameter was greater superficially than in deeper stromal regions. The interfibrillar spacing was also higher at mid-depth in the stroma than it was in anterior and posterior stromal regions. Collagen fibrils in the bovine cornea exhibited a fairly consistent spacing and diameter from the corneal centre to the 12 mm radial position, after which a significant increase was seen. While the constancy of the overall sulphation levels of proteoglycans in the cornea may correlate with the fibrillar architecture, there was no correlation between the latter and the distribution of low-sulphated KS. PMID:25019467

  6. Imaging articular cartilage using second harmonic generation microscopy

    NASA Astrophysics Data System (ADS)

    Mansfield, Jessica C.; Winlove, C. Peter; Knapp, Karen; Matcher, Stephen J.

    2006-02-01

    Sub cellular resolution images of equine articular cartilage have been obtained using both second harmonic generation microscopy (SHGM) and two-photon fluorescence microscopy (TPFM). The SHGM images clearly map the distribution of the collagen II fibers within the extracellular matrix while the TPFM images show the distribution of endogenous two-photon fluorophores in both the cells and the extracellular matrix, highlighting especially the pericellular matrix and bright 2-3μm diameter features within the cells. To investigate the source of TPF in the extracellular matrix experiments have been carried out to see if it may originate from the proteoglycans. Pure solutions of the following proteoglycans hyaluronan, chondroitin sulfate and aggrecan have been imaged, only the aggrecan produced any TPF and here the intensity was not great enough to account for the TPF in the extracellular matrix. Also cartilage samples were subjected to a process to remove proteoglycans and cellular components. After this process the TPF from the samples had decreased by a factor of two, with respect to the SHG intensity.

  7. Culture of human anulus fibrosus cells on polyamide nanofibers: extracellular matrix production.

    PubMed

    Gruber, Helen E; Hoelscher, Gretchen; Ingram, Jane A; Hanley, Edward N

    2009-01-01

    Studies were approved by the authors' Human Subjects Institutional Review Board. Human anulus cells were tested for growth and extracellular matrix (ECM) production in vitro. To investigate cell attachment, cell proliferation, and ECM production of human intervertebral disc anulus cells seeded onto randomly oriented electrospun polyamide nanofibers. Because nanofibrillar matrices have the potential to promote microenvironments, which may mimic in vivo conditions and resemble connective tissue, their utilization opens new avenues for cell-based tissue engineering applications for disc cells. Anulus cells were isolated from 4 cervical spine surgical disc specimens, expanded, and seeded into either routine plastic culture (control) or a nanofiber surface of randomly oriented electrospun polyamide nanofibers (Ultra-Web-coated culture dish, Corning) with a positive charge or without a charge. Cells were cultured for 9 days, digital images captured, cells harvested, embedded in paraffin, and examined for production of extracellular matrix (ECM). Additional anulus cultures were tested to quantitatively assess total proteoglycan production and cell proliferation under control or nanofiber cultures. Cells attached well and exhibited cell extensions within the nanofiber layers; cells on the charged nanofiber surface deposited greater amounts of chondroitin sulfate than of type II collagen than cells cultured on the uncharged nanofiber surface. Results showed that culture of anulus cells on nanofibers was permissive for secretion and assembly of type II collagen and chondroitin sulfate. Significantly greater total proteoglycan formation was present after culture on the nanofiber with added charge conditions {control, 0.6116 microg/mL +/- 0.186 [4] [mean +/- sem(n)] vs. 1.201 +/- 0.2509 [4], P < 0.05}. Cell proliferation, however, did not differ among treatment groups. Culture of anulus cells on nanofibers was found to be permissive for secretion and assembly of type II collagen and chondroitin sulfate, and culture on nanofibers with added charge significantly increased total proteoglycan production. These novel findings point to the need for further examination of nanofibrillar 3D culture of anulus cells for tissue engineering applications.

  8. The Role of Heparanase and Sulfatases in the Modification of Heparan Sulfate Proteoglycans within the Tumor Microenvironment and Opportunities for Novel Cancer Therapeutics

    PubMed Central

    Hammond, Edward; Khurana, Ashwani; Shridhar, Viji; Dredge, Keith

    2014-01-01

    Heparan sulfate proteoglycans (HSPGs) are an integral and dynamic part of normal tissue architecture at the cell surface and within the extracellular matrix. The modification of HSPGs in the tumor microenvironment is known to result not just in structural but also functional consequences, which significantly impact cancer progression. As substrates for the key enzymes sulfatases and heparanase, the modification of HSPGs is typically characterized by the degradation of heparan sulfate (HS) chains/sulfation patterns via the endo-6-O-sulfatases (Sulf1 and Sulf2) or by heparanase, an endo-glycosidase that cleaves the HS polymers releasing smaller fragments from HSPG complexes. Numerous studies have demonstrated how these enzymes actively influence cancer cell proliferation, signaling, invasion, and metastasis. The activity or expression of these enzymes has been reported to be modified in a variety of cancers. Such observations are consistent with the degradation of normal architecture and basement membranes, which are typically compromised in metastatic disease. Moreover, recent studies elucidating the requirements for these proteins in tumor initiation and progression exemplify their importance in the development and progression of cancer. Thus, as the influence of the tumor microenvironment in cancer progression becomes more apparent, the focus on targeting enzymes that degrade HSPGs highlights one approach to maintain normal tissue architecture, inhibit tumor progression, and block metastasis. This review discusses the role of these enzymes in the context of the tumor microenvironment and their promise as therapeutic targets for the treatment of cancer. PMID:25105093

  9. (S)-[6]-Gingerol inhibits TGF-β-stimulated biglycan synthesis but not glycosaminoglycan hyperelongation in human vascular smooth muscle cells.

    PubMed

    Kamato, Danielle; Babaahmadi Rezaei, Hossein; Getachew, Robel; Thach, Lyna; Guidone, Daniel; Osman, Narin; Roufogalis, Basil; Duke, Colin C; Tran, Van Hoan; Zheng, Wenhua; Little, Peter J

    2013-07-01

    (S)-[6]-Gingerol is under investigation for a variety of therapeutic uses. Transforming growth factor (TGF)-β stimulates proteoglycan synthesis, leading to increased binding of low-density lipoproteins, which is the initiating step in atherosclerosis. We evaluated the effects of (S)-[6]-gingerol on these TGF-β-mediated proteoglycan changes to explore its potential as an anti-atherosclerotic agent. Purified (S)-[6]-gingerol was assessed for its effects on proteoglycan synthesis by [(35) S]-sulfate incorporation into glycosaminoglycan chains and [(35) S]-Met/Cys incorporation into proteoglycans and total proteins in human vascular smooth muscle cells. Biglycan level was assessed by real-time quantitative polymerase chain reactions and the effects of (S)-[6]-gingerol on TGF-β signalling by assessment of the phosphorylation of Smads and Akt by western blotting. (S)-[6]-Gingerol concentration-dependently inhibited TGF-β-stimulated proteoglycan core protein synthesis, and this was not secondary to inhibition of total protein synthesis. (S)-[6]-Gingerol inhibited biglycan mRNA expression. (S)-[6]-Gingerol did not inhibit TGF-β-stimulated glycosaminoglycan hyperelongation or phosphorylation of Smad 2, in either the carboxy terminal or linker region, or Akt phosphorylation. The activity of (S)-[6]-gingerol to inhibit TGF-β-stimulated biglycan synthesis suggests a potential role for ginger in the prevention of atherosclerosis or other lipid-binding diseases. The signalling studies indicate a novel site of action of (S)-[6]-gingerol in inhibiting TGF-β responses. © 2013 Royal Pharmaceutical Society.

  10. Smad2-dependent glycosaminoglycan elongation in aortic valve interstitial cells enhances binding of LDL to proteoglycans.

    PubMed

    Osman, Narin; Grande-Allen, K Jane; Ballinger, Mandy L; Getachew, Robel; Marasco, Silvana; O'Brien, Kevin D; Little, Peter J

    2013-01-01

    Calcific aortic valve disease is a progressive condition that shares some common pathogenic features with atherosclerosis. Transforming growth factor-β1 is a recognized mediator of atherosclerosis and is expressed in aortic valve lesions. Transforming growth factorβ1 stimulates glycosaminoglycan elongation of proteoglycans that is associated with increased lipid binding. We investigated the presence of transforming growth factor-β1 and downstream signaling intermediates in diseased human aortic valves and the effects of activated transforming growth factor-β1 receptor signaling on aortic valve interstitial cell proteoglycan synthesis and lipid binding as a possible mechanism for the initiation of the early lesion of calcific aortic valve disease. Diseased human aortic valve leaflets demonstrated strong immunohistochemical staining for transforming growth factor-β1 and phosphorylated Smad2/3. In primary porcine aortic valve interstitial cells, Western blots showed that transforming growth factor-β1 stimulated phosphorylation in both the carboxy and linker regions of Smad2/3, which was inhibited by the transforming growth factor-β1 receptor inhibitor SB431542. Gel electrophoresis and size exclusion chromatography demonstrated that SB431542 decreased transforming growth factor-β1-mediated [(35)S]-sulfate incorporation into proteoglycans in a dose-dependent manner. Further, in proteoglycans derived from transforming growth factor-β1-treated valve interstitial cells, gel mobility shift assays demonstrated that inhibition of transforming growth factor-β1 receptor signaling resulted in decreased lipid binding. Classic transforming growth factor-β1 signaling is present in human aortic valves in vivo and contributes to the modification of proteoglycans expressed by valve interstitial cells in vitro. These findings suggest that transforming growth factor-β1 may promote increased low-density lipoprotein binding in the early phases of calcific aortic valve disease. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Induction of Syndecan-4 by Organic-Inorganic Hybrid Molecules with a 1,10-Phenanthroline Structure in Cultured Vascular Endothelial Cells.

    PubMed

    Hara, Takato; Kojima, Takayuki; Matsuzaki, Hiroka; Nakamura, Takehiro; Yoshida, Eiko; Fujiwara, Yasuyuki; Yamamoto, Chika; Saito, Shinichi; Kaji, Toshiyuki

    2017-02-08

    Organic-inorganic hybrid molecules constitute analytical tools used in biological systems. Vascular endothelial cells synthesize and secrete proteoglycans, which are macromolecules consisting of a core protein and glycosaminoglycan side chains. Although the expression of endothelial proteoglycans is regulated by several cytokines/growth factors, there may be alternative pathways for proteoglycan synthesis aside from downstream pathways activated by these cytokines/growth factors. Here, we investigated organic-inorganic hybrid molecules to determine a variant capable of analyzing the expression of syndecan-4, a transmembrane heparan-sulfate proteoglycan, and identified 1,10-phenanthroline ( o -Phen) with or without zinc (Zn-Phen) or rhodium (Rh-Phen). Bovine aortic endothelial cells in culture were treated with these compounds, and the expression of syndecan-4 mRNA and core proteins was determined by real-time reverse transcription polymerase chain reaction and Western blot analysis, respectively. Our findings indicated that o -Phen and Zn-Phen specifically and strongly induced syndecan-4 expression in cultured vascular endothelial cells through activation of the hypoxia-inducible factor-1α/β pathway via inhibition of prolyl hydroxylase-domain-containing protein 2. These results demonstrated an alternative pathway involved in mediating induction of endothelial syndecan-4 expression and revealed organic-inorganic hybrid molecules as effective tools for analyzing biological systems.

  12. Matrix metalloproteinase 9-mediated shedding of syndecan 4 in response to tumor necrosis factor α: a contributor to endothelial cell glycocalyx dysfunction.

    PubMed

    Ramnath, Raina; Foster, Rebecca R; Qiu, Yan; Cope, George; Butler, Matthew J; Salmon, Andrew H; Mathieson, Peter W; Coward, Richard J; Welsh, Gavin I; Satchell, Simon C

    2014-11-01

    The endothelial surface glycocalyx is a hydrated mesh in which proteoglycans are prominent. It is damaged in diseases associated with elevated levels of tumor necrosis factor α (TNF-α). We investigated the mechanism of TNF-α-induced disruption of the glomerular endothelial glycocalyx. We used conditionally immortalized human glomerular endothelial cells (GEnCs), quantitative PCR arrays, Western blotting, immunoprecipitation, immunofluorescence, and dot blots to examine the effects of TNF-α. TNF-α induced syndecan 4 (SDC4) mRNA up-regulation by 2.5-fold, whereas cell surface SDC4 and heparan sulfate (HS) were reduced by 36 and 30%, respectively, and SDC4 and sulfated glycosaminoglycan in the culture medium were increased by 52 and 65%, respectively, indicating TNF-α-induced shedding. Small interfering (siRNA) knockdown of SDC4 (by 52%) caused a corresponding loss of cell surface HS of similar magnitude (38%), and immunoprecipitation demonstrated that SDC4 and HS are shed as intact proteoglycan ectodomains. All of the effects of TNF-α on SDC4 and HS were abrogated by the metalloproteinase (MMP) inhibitor batimastat. Also abrogated was the associated 37% increase in albumin passage across GEnC monolayers. Specific MMP9 knockdown by siRNA similarly blocked TNF-α effects. SDC4 is the predominant HS proteoglycan in the GEnC glycocalyx. TNF-α-induced MMP9-mediated shedding of SDC4 is likely to contribute to the endothelial glycocalyx disruption observed in diabetes and inflammatory states. © FASEB.

  13. Additionally sulfated xylomannan sulfates from Scinaia hatei and their antiviral activities.

    PubMed

    Ray, Sayani; Pujol, Carlos A; Damonte, Elsa B; Ray, Bimalendu

    2015-10-20

    Herpes simplex viruses (HSVs) display affinity for cell-surface heparan sulfate proteoglycans with biological relevance in virus entry. This study demonstrates the potential of chemically engineered sulfated xylomannans from Scinaia hatei as antiHSV drug candidate. Particularly, a dimethylformamide -SO3/pyridine based procedure has been employed for the generation of anionic polysaccharides. This one-step procedure has the power of providing a spectrum of xylomannans with varying molecular masses (<12-74kDa), sulfate content (1-50%) and glycosyl composition. Especially, the sulfated xylomannans S1F1 and S2F1 possessed altered activity against HSV-1 and HSV-2 compared to the parental compound (F1) and that too in the absence of drug-induced cytotoxicity. Regarding methodological facet, the directive decoration of hydroxyl functionality with sulfate group plus changes in the molecular mass and sugar composition during isolation by the used reagent opens a door for the production of new molecular entity with altered biological activity from other natural sources. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Search and Neutralize Factors (CSPGs) that Induce Decline in Transmission to Neurons from Spared Fibers after Chronic Spinal Cord Injury

    DTIC Science & Technology

    2012-10-01

    damaged spinal cord after chronic HX are the result of reduced conduction in uncut axons (Hunanyan et al. 2011). Since elevated level of chondroitin ... sulfate proteoglycans (CSPGs) in the vicinity of the injury has been reported to be a major obstacle for recovery after SCI (Snow et al., 1990; Jones

  15. Combinatorial Roles of Heparan Sulfate Proteoglycans and Heparan Sulfates in Caenorhabditis elegans Neural Development

    PubMed Central

    Kinnunen, Tarja K.

    2014-01-01

    Heparan sulfate proteoglycans (HSPGs) play critical roles in the development and adult physiology of all metazoan organisms. Most of the known molecular interactions of HSPGs are attributed to the structurally highly complex heparan sulfate (HS) glycans. However, whether a specific HSPG (such as syndecan) contains HS modifications that differ from another HSPG (such as glypican) has remained largely unresolved. Here, a neural model in C. elegans is used to demonstrate for the first time the relationship between specific HSPGs and HS modifications in a defined biological process in vivo. HSPGs are critical for the migration of hermaphrodite specific neurons (HSNs) as genetic elimination of multiple HSPGs leads to 80% defect of HSN migration. The effects of genetic elimination of HSPGs are additive, suggesting that multiple HSPGs, present in the migrating neuron and in the matrix, act in parallel to support neuron migration. Genetic analyses suggest that syndecan/sdn-1 and HS 6-O-sulfotransferase, hst-6, function in a linear signaling pathway and glypican/lon-2 and HS 2-O-sulfotransferase, hst-2, function together in a pathway that is parallel to sdn-1 and hst-6. These results suggest core protein specific HS modifications that are critical for HSN migration. In C. elegans, the core protein specificity of distinct HS modifications may be in part regulated at the level of tissue specific expression of genes encoding for HSPGs and HS modifying enzymes. Genetic analysis reveals that there is a delicate balance of HS modifications and eliminating one HS modifying enzyme in a compromised genetic background leads to significant changes in the overall phenotype. These findings are of importance with the view of HS as a critical regulator of cell signaling in normal development and disease. PMID:25054285

  16. Targeting Heparan Sulfate Proteoglycans and their Modifying Enzymes to Enhance Anticancer Chemotherapy Efficacy and Overcome Drug Resistance.

    PubMed

    Lanzi, Cinzia; Zaffaroni, Nadia; Cassinelli, Giuliana

    2017-01-01

    Targeting heparan sulfate proteoglycans (HSPGs) and enzymes involved in heparan sulfate (HS) chain editing is emerging as a new anticancer strategy. The involvement of HSPGs in tumor cell signaling, inflammation, angiogenesis and metastasis indicates that agents able to inhibit aberrant HSPG functions can potentially act as multitarget drugs affecting both tumor cell growth and the supportive boost provided by the microenvironment. Moreover, accumulating evidence supports that an altered expression or function of HSPGs, or of the complex enzyme system regulating their activities, can also depress the tumor response to anticancer treatments in several tumor types. Thereby, targeting HSPGs or HSPG modifying enzymes appears an appealing approach to enhance chemotherapy efficacy. A great deal of effort from academia and industry has led to the development of agents mimicking HS, and/or inhibiting HSPG modifying enzymes. Inhibitors of Sulf-2, an endosulfatase that edits the HS sulfation pattern, and inhibitors of heparanase, the endoglycosidase that produces functional HS fragments, appear particularly promising. In fact, a Sulf-2 inhibitor (OKN-007), and two heparanase inhibitors/HS mimics (roneparstat, PG545) are currently under early clinical investigation. In this review, we summarized preclinical studies in experimental tumor models of the main chemical classes of Sulf-2 and heparanase inhibitors. We described examples of different mechanisms through which heparanase and HSPGs, often in cooperation, may impact tumor sensitivity to various antitumor agents. Finally, we reported a few preclinical studies showing increased antitumor efficacy obtained with the use of candidate clinical HS mimics in combination regimens. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. Heparan sulfate proteoglycans mediate renal carcinoma metastasis.

    PubMed

    Qazi, Henry; Shi, Zhong-Dong; Song, Jonathan W; Cancel, Limary M; Huang, Peigen; Zeng, Ye; Roberge, Sylvie; Munn, Lance L; Tarbell, John M

    2016-12-15

    The surface proteoglycan/glycoprotein layer (glycocalyx) on tumor cells has been associated with cellular functions that can potentially enable invasion and metastasis. In addition, aggressive tumor cells with high metastatic potential have enhanced invasion rates in response to interstitial flow stimuli in vitro. Our previous studies suggest that heparan sulfate (HS) in the glycocalyx plays an important role in this flow mediated mechanostransduction and upregulation of invasive and metastatic potential. In this study, highly metastatic renal cell carcinoma cells were genetically modified to suppress HS production by knocking down its synthetic enzyme NDST1. Using modified Boyden chamber and microfluidic assays, we show that flow-enhanced invasion is suppressed in HS deficient cells. To assess the ability of these cells to metastasize in vivo, parental or knockdown cells expressing fluorescence reporters were injected into kidney capsules in SCID mice. Histological analysis confirmed that there was a large reduction (95%) in metastasis to distant organs by tumors formed from the NDST1 knockdown cells compared to control cells with intact HS. The ability of these cells to invade surrounding tissue was also impaired. The substantial inhibition of metastasis and invasion upon reduction of HS suggests an active role for the tumor cell glycocalyx in tumor progression. © 2016 UICC.

  18. Agrin and Perlecan Mediate Tumorigenic Processes in Oral Squamous Cell Carcinoma

    PubMed Central

    Kawahara, Rebeca; Granato, Daniela C.; Carnielli, Carolina M.; Cervigne, Nilva K.; Oliveria, Carine E.; Martinez, César A. R.; Yokoo, Sami; Fonseca, Felipe P.; Lopes, Marcio; Santos-Silva, Alan R.; Graner, Edgard; Coletta, Ricardo D.; Leme, Adriana Franco Paes

    2014-01-01

    Oral squamous cell carcinoma is the most common type of cancer in the oral cavity, representing more than 90% of all oral cancers. The characterization of altered molecules in oral cancer is essential to understand molecular mechanisms underlying tumor progression as well as to contribute to cancer biomarker and therapeutic target discovery. Proteoglycans are key molecular effectors of cell surface and pericellular microenvironments, performing multiple functions in cancer. Two of the major basement membrane proteoglycans, agrin and perlecan, were investigated in this study regarding their role in oral cancer. Using real time quantitative PCR (qRT-PCR), we showed that agrin and perlecan are highly expressed in oral squamous cell carcinoma. Interestingly, cell lines originated from distinct sites showed different expression of agrin and perlecan. Enzymatically targeting chondroitin sulfate modification by chondroitinase, oral squamous carcinoma cell line had a reduced ability to adhere to extracellular matrix proteins and increased sensibility to cisplatin. Additionally, knockdown of agrin and perlecan promoted a decrease on cell migration and adhesion, and on resistance of cells to cisplatin. Our study showed, for the first time, a negative regulation on oral cancer-associated events by either targeting chondroitin sulfate content or agrin and perlecan levels. PMID:25506919

  19. The effect of divalent salt in chondroitin sulfate solutions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aranghel, D., E-mail: daranghe@nipne.ro; Extreme Light Intrastructure Nuclear Physics; Badita, C. R.

    Chondroitin-4 sulfate (CS4) is the main glycosaminoglycan extracted from bovine trachea. CS4 play an important role in osteoarthritis treatment, anticoagulant activity, reduces the degradation of cartilage matrix components, reduces necrosis and apoptosis of chondrocytes and reduces the activity of collagenase. Chondroitin sulfate is also responsible for proteoglycans degradation. Chondroitin sulfate can bind calcium ions with different affinities, depending on their sulfation position. The purpose of this study was to determine the structural properties and the influence of Ca{sup 2+} cations. We carried out measurements on CS4 solutions and mixtures of liquid CS4 with Ca{sup 2+} by Small-Angle Neutron Scattering (SANS).more » CS4 have a mass fractal behavior and the addition of a salt (CaCl{sub 2}) in CS4 solutions generates the appearance of a correlation peak due to local ordering between adjacent chains with inter-chain distances between 483 Å and 233 Å for a calcium concentration of 0.01% w/w.« less

  20. The effect of divalent salt in chondroitin sulfate solutions

    NASA Astrophysics Data System (ADS)

    Aranghel, D.; Badita, C. R.; Radulescu, A.; Moldovan, L.; Craciunescu, O.; Balasoiu, M.

    2016-03-01

    Chondroitin-4 sulfate (CS4) is the main glycosaminoglycan extracted from bovine trachea. CS4 play an important role in osteoarthritis treatment, anticoagulant activity, reduces the degradation of cartilage matrix components, reduces necrosis and apoptosis of chondrocytes and reduces the activity of collagenase. Chondroitin sulfate is also responsible for proteoglycans degradation. Chondroitin sulfate can bind calcium ions with different affinities, depending on their sulfation position. The purpose of this study was to determine the structural properties and the influence of Ca2+ cations. We carried out measurements on CS4 solutions and mixtures of liquid CS4 with Ca2+ by Small-Angle Neutron Scattering (SANS). CS4 have a mass fractal behavior and the addition of a salt (CaCl2) in CS4 solutions generates the appearance of a correlation peak due to local ordering between adjacent chains with inter-chain distances between 483 Å and 233 Å for a calcium concentration of 0.01% w/w.

  1. Artemin Crystal Structure Reveals Insights into Heparan Sulfate Binding

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Silvian,L.; Jin, P.; Carmillo, P.

    2006-01-01

    Artemin (ART) promotes the growth of developing peripheral neurons by signaling through a multicomponent receptor complex comprised of a transmembrane tyrosine kinase receptor (cRET) and a specific glycosylphosphatidylinositol-linked co-receptor (GFR{alpha}3). Glial cell line-derived neurotrophic factor (GDNF) signals through a similar ternary complex but requires heparan sulfate proteoglycans (HSPGs) for full activity. HSPG has not been demonstrated as a requirement for ART signaling. We crystallized ART in the presence of sulfate and solved its structure by isomorphous replacement. The structure reveals ordered sulfate anions bound to arginine residues in the pre-helix and amino-terminal regions that were organized in a triad arrangementmore » characteristic of heparan sulfate. Three residues in the pre-helix were singly or triply substituted with glutamic acid, and the resulting proteins were shown to have reduced heparin-binding affinity that is partly reflected in their ability to activate cRET. This study suggests that ART binds HSPGs and identifies residues that may be involved in HSPG binding.« less

  2. Mucopolysaccharidosis IVA and glycosaminoglycans.

    PubMed

    Khan, Shaukat; Alméciga-Díaz, Carlos J; Sawamoto, Kazuki; Mackenzie, William G; Theroux, Mary C; Pizarro, Christian; Mason, Robert W; Orii, Tadao; Tomatsu, Shunji

    Mucopolysaccharidosis IVA (MPS IVA; Morquio A: OMIM 253000) is a lysosomal storage disease with an autosomal recessive trait caused by the deficiency of N-acetylgalactosamine-6-sulfate sulfatase. Deficiency of this enzyme leads to accumulation of specific glycosaminoglycans (GAGs): chondroitin-6-sulfate (C6S) and keratan sulfate (KS). C6S and KS are mainly produced in the cartilage. Therefore, the undegraded substrates are stored primarily in cartilage and in its extracellular matrix (ECM), leading to a direct impact on cartilage and bone development, and successive systemic skeletal dysplasia. Chondrogenesis, the earliest phase of skeletal formation, is maintained by cellular interactions with the ECM, growth and differentiation factors, signaling pathways, and transcription factors in a temporal-spatial manner. In patients with MPS IVA, the cartilage is disrupted at birth as a consequence of abnormal chondrogenesis and/or endochondral ossification. The unique skeletal features are distinguished by a disproportional short stature, odontoid hypoplasia, spinal cord compression, tracheal obstruction, pectus carinatum, kyphoscoliosis, platyspondyly, coxa valga, genu valgum, waddling gait, and laxity of joints. In spite of many descriptions of these unique clinical features, delay of diagnosis still happens. The pathogenesis and treatment of systemic skeletal dysplasia in MPS IVA remains an unmet challenge. In this review article, we comprehensively describe historical aspect, property of GAGs, diagnosis, screening, pathogenesis, and current and future therapies of MPS IVA. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Corneal Sulfated Glycosaminoglycans and Their Effects on Trigeminal Nerve Growth Cone Behavior In Vitro: Roles for ECM in Cornea Innervation

    PubMed Central

    Schwend, Tyler; Deaton, Ryan J.; Zhang, Yuntao; Caterson, Bruce; Conrad, Gary W.

    2012-01-01

    Purpose. Sensory trigeminal nerve growth cones innervate the cornea in a highly coordinated fashion. The purpose of this study was to determine if extracellular matrix glycosaminoglycans (ECM–GAGs), including keratan sulfate (KS), dermatan sulfate (DS), and chondroitin sulfate A (CSA) and C (CSC), polymerized in developing eyefronts, may provide guidance cues to nerves during cornea innervation. Methods. Immunostaining using antineuron-specific-β-tubulin and monoclonal antibodies for KS, DS, and CSA/C was performed on eyefronts from embryonic day (E) 9 to E14 and staining visualized by confocal microscopy. Effects of purified GAGs on trigeminal nerve growth cone behavior were tested using in vitro neuronal explant cultures. Results. At E9 to E10, nerves exiting the pericorneal nerve ring grew as tight fascicles, advancing straight toward the corneal stroma. In contrast, upon entering the stroma, nerves bifurcated repeatedly as they extended anteriorly toward the epithelium. KS was localized in the path of trigeminal nerves, whereas DS and CSA/C–rich areas were avoided by growth cones. When E10 trigeminal neurons were cultured on different substrates comprised of purified GAG molecules, their neurite growth cone behavior varied depending on GAG type, concentration, and mode of presentation (immobilized versus soluble). High concentrations of immobilized KS, DS, and CSA/C inhibited neurite growth to varying degrees. Neurites traversing lower, permissive concentrations of immobilized DS and CSA/C displayed increased fasciculation and decreased branching, whereas KS caused decreased fasciculation and increased branching. Enzymatic digestion of sulfated GAGs canceled their effects on trigeminal neurons. Conclusions. Data herein suggest that GAGs may direct the movement of trigeminal nerve growth cones innervating the cornea. PMID:23132805

  4. Expression of the cell-surface heparan sulfate proteoglycan syndecan-2 in developing rat anterior pituitary gland.

    PubMed

    Horiguchi, Kotaro; Syaidah, Rahimi; Fujiwara, Ken; Tsukada, Takehiro; Ramadhani, Dini; Jindatip, Depicha; Kikuchi, Motoshi; Yashiro, Takashi

    2013-09-01

    In the anterior pituitary gland, folliculo-stellate cells and five types of hormone-producing cells are surrounded by an extracellular matrix (ECM) essential for these cells to perform their respective roles. Syndecans-type I transmembrane cell-surface heparan sulfate proteoglycans act as major ECM coreceptors via their respective heparan sulfate chains and efficiently transduce intracellular signals through the convergent action of their transmembrane and cytoplasmic domains. The syndecans comprise four family members in vertebrates: syndecan-1, -2, -3 and -4. However, whether syndecans are produced in the pituitary gland or whether they have a role as a coreceptor is not known. We therefore used (1) reverse transcription plus the polymerase chain reaction to analyze the expression of syndecan genes and (2) immunohistochemical techniques to identify the cells that produce the syndecans in the anterior pituitary gland of adult rat. Syndecan-2 mRNA expression was clearly detected in the corticotropes of the anterior pituitary gland. Moreover, the expression of syndecan-2 in the developing pituitary gland had a distinct temporospatial pattern. To identify the cells expressing syndecan-2 in the developing pituitary gland, we used double-immunohistochemistry for syndecan-2 and the cell markers E-cadherin (immature cells) and Ki-67 (proliferating cells). Some E-cadherin- and Ki-67-immunopositive cells expressed syndecan-2. Therefore, syndecan-2 expression occurs in developmentally regulated patterns and syndecan-2 probably has different roles in adult and developing anterior pituitary glands.

  5. The involvement of heparan sulfate proteoglycans in stem cell differentiation and in malignant glioma

    NASA Astrophysics Data System (ADS)

    Kundu, Soumi; Xiong, Anqi; Forsberg-Nilsson, Karin

    2016-04-01

    Heparan sulfate (HS) proteoglycans (HSPG) are major components of the extracellular matrix. They interact with a plethora of macromolecules that are of physiological importance. The pattern of sulfation of the HS chain determines the specificity of these interactions. The enzymes that synthesize and degrade HS are thus key regulators of processes ranging from embryonic development to tissue homeostasis and tumor development. Formation of the nervous system is also critically dependent on appropriate HSPGs as shown by several studies on the role of HS in neural induction from embryonic stem cells. High-grade glioma is the most common primary malignant brain tumor among adults, and the prognosis is poor. Neural and glioma stem cells share several traits, including sustained proliferation and highly efficient migration in the brain. There are also similarities between the neurogenic niche where adult neural stem cells reside and the tumorigenic niche, including their interactions with components of the extracellular matrix (ECM). The levels of many of these components, for example HSPGs and enzymes involved in the biosynthesis and modification of HS are attenuated in gliomas. In this paper, HS regulation of pathways involved in neural differentiation and how these may be of importance for brain development are discussed. The literature suggesting that modifications of HS could regulate glioma growth and invasion is reviewed. Targeting the invasiveness of glioma cells by modulating HS may improve upon present therapeutic options, which only marginally enhance the survival of glioma patients.

  6. Placental Sequestration of Plasmodium falciparum Malaria Parasites Is Mediated by the Interaction Between VAR2CSA and Chondroitin Sulfate A on Syndecan-1

    PubMed Central

    Mao, Yang; Resende, Mafalda; Daugaard, Mads; Riis Kristensen, Anders; Damm, Peter; G. Theander, Thor; R. Hansson, Stefan; Salanti, Ali

    2016-01-01

    During placental malaria, Plasmodium falciparum infected erythrocytes sequester in the placenta, causing health problems for both the mother and fetus. The specific adherence is mediated by the VAR2CSA protein, which binds to placental chondroitin sulfate (CS) on chondroitin sulfate proteoglycans (CSPGs) in the placental syncytium. However, the identity of the CSPG core protein and the cellular impact of the interaction have remain elusive. In this study we identified the specific CSPG core protein to which the CS is attached, and characterized its exact placental location. VAR2CSA pull-down experiments using placental extracts from whole placenta or syncytiotrophoblast microvillous cell membranes showed three distinct CSPGs available for VAR2CSA adherence. Further examination of these three CSPGs by immunofluorescence and proximity ligation assays showed that syndecan-1 is the main receptor for VAR2CSA mediated placental adherence. We further show that the commonly used placental choriocarcinoma cell line, BeWo, express a different set of proteoglycans than those present on placental syncytiotrophoblast and may not be the most biologically relevant model to study placental malaria. Syncytial fusion of the BeWo cells, triggered by forskolin treatment, caused an increased expression of placental CS-modified syndecan-1. In line with this, we show that rVAR2 binding to placental CS impairs syndecan-1-related Src signaling in forskolin treated BeWo cells, but not in untreated cells. PMID:27556547

  7. High sodium diet converts renal proteoglycans into pro-inflammatory mediators in rats

    PubMed Central

    Shrestha, Pragyi; Sarpong, Kwaku A.; Yazdani, Saleh; el Masri, Rana; de Jong, Wilhelmina H. A.; Navis, Gerjan; Vivès, Romain R.; van den Born, Jacob

    2017-01-01

    Background High dietary sodium aggravates renal disease by affecting blood pressure and by its recently shown pro-inflammatory and pro-fibrotic effects. Moreover, pro-inflammatory modification of renal heparan sulfate (HS) can induce tissue remodeling. We aim to investigate if high sodium intake in normotensive rats converts renal HS into a pro-inflammatory phenotype, able to bind more sodium and orchestrate inflammation, fibrosis and lymphangiogenesis. Methods Wistar rats received a normal diet for 4 weeks, or 8% NaCl diet for 2 or 4 weeks. Blood pressure was monitored, and plasma, urine and tissue collected. Tissue sodium was measured by flame spectroscopy. Renal HS and tubulo-interstitial remodeling were studied by biochemical, immunohistochemical and qRT-PCR approaches. Results High sodium rats showed a transient increase in blood pressure (week 1; p<0.01) and increased sodium excretion (p<0.05) at 2 and 4 weeks compared to controls. Tubulo-interstitial T-cells, myofibroblasts and mRNA levels of VCAM1, TGF-β1 and collagen type III significantly increased after 4 weeks (all p<0.05). There was a trend for increased macrophage infiltration and lymphangiogenesis (both p = 0.07). Despite increased dermal sodium over time (p<0.05), renal concentrations remained stable. Renal HS of high sodium rats showed increased sulfation (p = 0.05), increased L-selectin binding to HS (p<0,05), and a reduction of sulfation-sensitive anti-HS mAbs JM403 (p<0.001) and 10E4 (p<0.01). Hyaluronan expression increased under high salt conditions (p<0.01) without significant changes in the chondroitin sulfate proteoglycan versican. Statistical analyses showed that sodium-induced tissue remodeling responses partly correlated with observed HS changes. Conclusion We show that high salt intake by healthy normotensive rats convert renal HS into high sulfated pro-inflammatory glycans involved in tissue remodeling events, but not in increased sodium storage. PMID:28594849

  8. Studies of proteoglycan involvement in CPP-mediated delivery.

    PubMed

    Wittrup, Anders; Zhang, Si-He; Belting, Mattias

    2011-01-01

    Cell-penetrating peptides (CPPs) are widely used to deliver macromolecular cargoes to intracellular sites of action. Many CPPs have been demonstrated to rely on cell surface heparan sulfate proteoglycans (HSPGs) for efficient cellular entry and delivery. In this chapter, we describe methods for the study of PG involvement in CPP uptake. We provide descriptions of how to determine whether uptake of a CPP of interest is dependent on PGs. We also provide detailed protocols for the purification of PGs by anion-exchange chromatography as well as the characterization of the HSPG core protein composition of a cell line of interest. Finally, we present methods for modulating the expression level of specific HSPG core proteins as a means to determine the core protein specificity in the uptake of a particular CPP.

  9. Synthesis and Characterization of a Chondroitin Sulfate Based Hybrid Bio/Synthetic Biomimetic Aggrecan Macromolecule

    NASA Astrophysics Data System (ADS)

    Sarkar, Sumona

    Lower back pain resulting from intervertebral disc degeneration is one of the leading musculoskeletal disorders confronting our health system. In order to mechanically stabilize the disc early in the degenerative cascade and prevent the need for spinal fusion surgeries, we have proposed the development of a hybrid-bio/synthetic biomimetic proteoglycan macromolecule for injection into the disc in the early stages of degeneration. The goal of this thesis was to incorporate natural chondroitin sulfate (CS) chains into bottle brush polymer synthesis strategies for the fabrication of CS-macromolecules which mimic the proteoglycan structure and function while resisting enzymatic degradation. Both the "grafting-to" and "grafting-through" techniques of bottle brush synthesis were explored. CS was immobilized via a terminal primary amine onto a model polymeric backbone (polyacrylic acid) for investigation of the "grafting-to" strategy and an epoxy-amine step-growth polymerization technique was utilized for the "grafting-through" synthesis of CS-macromolecules with polyethylene glycol backbone segments. Incorporation of a synthetic polymeric backbone at the terminal amine of CS was confirmed via biochemical assays, 1H-NMR and FTIR spectroscopy, and CS-macromolecule size was demonstrated to be higher than that of natural CS via gel permeation chromatography, transmission electron microscopy and viscosity measurements. Further analysis of CS-macromolecule functionality indicated maintenance of natural CS properties such as high fixed charge density, high osmotic potential and low cytotoxicity with nucleus pulposus cells. These studies are the first attempt at the incorporation of natural CS into biomimetic bottle brush structures. CS-macromolecules synthesized via the methods developed in these studies may be utilized in the treatment and prevention of debilitating back pain as well as act as mimetics for other proteoglycans implicated in cartilage, heart valve, and nervous system tissue function.

  10. Mucin (MUC1) Expression and Function in Prostate Cancer Cells

    DTIC Science & Technology

    2001-09-01

    Interactions at the Cell Surface of Mouse Uterine Epithelial Cells and Periimplantation -Stage Embryos. Trophoblast Res., 4:211-241, 1990. 37. Dutt...and Julian, J. Heparan Sulfate Proteoglycan Expression by Periimplantation Stage Embryos. Dev. Biol. 155:97-106,1993. 56. Rohde, L.H., and Carson...Modulators of Embryo-Uterine Epithelial Cell Attachment. In: S.K. Dey (ed.), Molecular and Cellular Aspects of Periimplantation Processes, Springer

  11. Experience-dependent development of perineuronal nets and chondroitin sulfate proteoglycan receptors in mouse visual cortex.

    PubMed

    Ye, Qian; Miao, Qing-Long

    2013-08-08

    Perineuronal nets (PNNs) are extracellular matrix structures consisting of chondroitin sulfate proteoglycans (CSPGs), hyaluronan, link proteins and tenascin-R (Tn-R). They enwrap a subset of GABAergic inhibitory interneurons in the cerebral cortex and restrict experience-dependent cortical plasticity. While the expression profile of PNN components has been widely studied in many areas of the central nervous system of various animal species, it remains unclear how these components are expressed during the postnatal development of mouse primary visual cortex (V1). In the present study, we characterized the developmental time course of the formation of PNNs in the mouse primary visual cortex, using the specific antibodies against the two PNN component proteins aggrecan and tenascin-R, or the lectin Wisteria floribunda agglutinin (WFA) that directly binds to glycosaminoglycan chains of chondroitin sulfate proteoglycans (CSPGs). We found that the fluorescence staining signals of both the WFA staining and the antibody against aggrecan rapidly increased in cortical neurons across layers 2-6 during postnatal days (PD) 10-28 and reached a plateau around PD42, suggesting a full construction of PNNs by the end of the critical period. Co-staining with antibodies to Ca(2+) binding protein parvalbumin (PV) demonstrated that the majority of PNN-surrounding cortical neurons are immunoreactive to PV. Similar expression profile of another PNN component tenascin-R was observed in the development of V1. Dark rearing of mice from birth significantly reduced the density of PNN-surrounding neurons. In addition, the expression of two recently identified CSPG receptors - Nogo receptor (NgR) and leukocyte common antigen-related phosphatase (LAR), showed significant increases from PD14 to PD70 in layer 2-6 of cortical PV-positive interneurons in normal reared mice, but decreased significantly in dark-reared ones. Taken together, these results suggest that PNNs form preferentially in cortical PV-positive interneurons in an experience-dependent manner, and reach full maturation around the end of the critical period of V1 development. © Elsevier B.V. All rights reserved.

  12. Monoclonal Antibody and an Antibody-Toxin Conjugate to a Cell Surface Proteoglycan of Melanoma Cells Suppress in vivo Tumor Growth

    NASA Astrophysics Data System (ADS)

    Bumol, T. F.; Wang, Q. C.; Reisfeld, R. A.; Kaplan, N. O.

    1983-01-01

    A monoclonal antibody directed against a cell surface chondroitin sulfate proteoglycan of human melanoma cells, 9.2.27, and its diphtheria toxin A chain (DTA) conjugate were investigated for their effects on in vitro protein synthesis and in vivo tumor growth of human melanoma cells. The 9.2.27 IgG and its DTA conjugate display similar serological activities against melanoma target cells but only the conjugate can induce consistent in vitro inhibition of protein synthesis and toxicity in M21 melanoma cells. However, both 9.2.27 IgG and its DTA conjugate effect significant suppression of M21 tumor growth in vivo in an immunotherapy model of a rapidly growing tumor in athymic nu/nu mice, suggesting that other host mechanisms may mediate monoclonal antibody-induced tumor suppression.

  13. Biphasic Role of Chondroitin Sulfate in Cardiac Differentiation of Embryonic Stem Cells through Inhibition of Wnt/β-Catenin Signaling

    PubMed Central

    Prinz, Robert D.; Willis, Catherine M.; van Kuppevelt, Toin H.; Klüppel, Michael

    2014-01-01

    The glycosaminoglycan chondroitin sulfate is a critical component of proteoglycans on the cell surface and in the extracellular matrix. As such, chondroitin sulfate side chains and the sulfation balance of chondroitin play important roles in the control of signaling pathways, and have a functional importance in human disease. In contrast, very little is known about the roles of chondroitin sulfate molecules and sulfation patterns during mammalian development and cell lineage specification. Here, we report a novel biphasic role of chondroitin sulfate in the specification of the cardiac cell lineage during embryonic stem cell differentiation through modulation of Wnt/beta-catenin signaling. Lineage marker analysis demonstrates that enzymatic elimination of endogenous chondroitin sulfates leads to defects specifically in cardiac differentiation. This is accompanied by a reduction in the number of beating cardiac foci. Mechanistically, we show that endogenous chondroitin sulfate controls cardiac differentiation in a temporal biphasic manner through inhibition of the Wnt/beta-catenin pathway, a known regulatory pathway for the cardiac lineage. Treatment with a specific exogenous chondroitin sulfate, CS-E, could mimic these biphasic effects on cardiac differentiation and Wnt/beta-catenin signaling. These results establish chondroitin sulfate and its sulfation balance as important regulators of cardiac cell lineage decisions through control of the Wnt/beta-catenin pathway. Our work suggests that targeting the chondroitin biosynthesis and sulfation machinery is a novel promising avenue in regenerative strategies after heart injury. PMID:24667694

  14. Biphasic role of chondroitin sulfate in cardiac differentiation of embryonic stem cells through inhibition of Wnt/β-catenin signaling.

    PubMed

    Prinz, Robert D; Willis, Catherine M; van Kuppevelt, Toin H; Klüppel, Michael

    2014-01-01

    The glycosaminoglycan chondroitin sulfate is a critical component of proteoglycans on the cell surface and in the extracellular matrix. As such, chondroitin sulfate side chains and the sulfation balance of chondroitin play important roles in the control of signaling pathways, and have a functional importance in human disease. In contrast, very little is known about the roles of chondroitin sulfate molecules and sulfation patterns during mammalian development and cell lineage specification. Here, we report a novel biphasic role of chondroitin sulfate in the specification of the cardiac cell lineage during embryonic stem cell differentiation through modulation of Wnt/beta-catenin signaling. Lineage marker analysis demonstrates that enzymatic elimination of endogenous chondroitin sulfates leads to defects specifically in cardiac differentiation. This is accompanied by a reduction in the number of beating cardiac foci. Mechanistically, we show that endogenous chondroitin sulfate controls cardiac differentiation in a temporal biphasic manner through inhibition of the Wnt/beta-catenin pathway, a known regulatory pathway for the cardiac lineage. Treatment with a specific exogenous chondroitin sulfate, CS-E, could mimic these biphasic effects on cardiac differentiation and Wnt/beta-catenin signaling. These results establish chondroitin sulfate and its sulfation balance as important regulators of cardiac cell lineage decisions through control of the Wnt/beta-catenin pathway. Our work suggests that targeting the chondroitin biosynthesis and sulfation machinery is a novel promising avenue in regenerative strategies after heart injury.

  15. Heparan sulfate proteoglycans regulate autophagy in Drosophila.

    PubMed

    Reynolds-Peterson, Claire E; Zhao, Na; Xu, Jie; Serman, Taryn M; Xu, Jielin; Selleck, Scott B

    2017-08-03

    Heparan sulfate-modified proteoglycans (HSPGs) are important regulators of signaling and molecular recognition at the cell surface and in the extracellular space. Disruption of HSPG core proteins, HS-synthesis, or HS-degradation can have profound effects on growth, patterning, and cell survival. The Drosophila neuromuscular junction provides a tractable model for understanding the activities of HSPGs at a synapse that displays developmental and activity-dependent plasticity. Muscle cell-specific knockdown of HS biosynthesis disrupted the organization of a specialized postsynaptic membrane, the subsynaptic reticulum (SSR), and affected the number and morphology of mitochondria. We provide evidence that these changes result from a dysregulation of macroautophagy (hereafter referred to as autophagy). Cellular and molecular markers of autophagy are all consistent with an increase in the levels of autophagy in the absence of normal HS-chain biosynthesis and modification. HS production is also required for normal levels of autophagy in the fat body, the central energy storage and nutritional sensing organ in Drosophila. Genetic mosaic analysis indicates that HS-dependent regulation of autophagy occurs non-cell autonomously, consistent with HSPGs influencing this cellular process via signaling in the extracellular space. These findings demonstrate that HS biosynthesis has important regulatory effects on autophagy and that autophagy is critical for normal assembly of postsynaptic membrane specializations.

  16. Perlecan, a heparan sulfate proteoglycan, regulates systemic metabolism with dynamic changes in adipose tissue and skeletal muscle.

    PubMed

    Yamashita, Yuri; Nakada, Satoshi; Yoshihara, Toshinori; Nara, Takeshi; Furuya, Norihiko; Miida, Takashi; Hattori, Nobutaka; Arikawa-Hirasawa, Eri

    2018-05-17

    Perlecan (HSPG2), a heparan sulfate proteoglycan, is a component of basement membranes and participates in a variety of biological activities. Here, we show physiological roles of perlecan in both obesity and the onset of metabolic syndrome. The perinatal lethality-rescued perlecan knockout (Hspg2 -/- -Tg) mice showed a smaller mass and cell size of white adipose tissues than control (WT-Tg) mice. Abnormal lipid deposition, such as fatty liver, was not detected in the Hspg2 -/- -Tg mice, and those mice also consumed more fat as an energy source, likely due to their activated fatty acid oxidation. In addition, the Hspg2 -/- -Tg mice demonstrated increased insulin sensitivity. Molecular analysis revealed the significantly relatively increased amount of the muscle fiber type IIA (X) isoform and a larger quantity of mitochondria in the skeletal muscle of Hspg2 -/- -Tg mice. Furthermore, the perlecan-deficient skeletal muscle also had elevated levels of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) protein. PGC1α expression is activated by exercise, and induces mitochondrial biosynthesis. Thus, perlecan may act as a mechano-regulator of catabolism of both lipids and glucose by shifting the muscle fiber composition to oxidative fibers. Our data suggest that downregulation of perlecan is a promising strategy to control metabolic syndrome.

  17. Acute Exacerbations of COPD Are Associated With Increased Expression of Heparan Sulfate and Chondroitin Sulfate in BAL.

    PubMed

    Papakonstantinou, Eleni; Klagas, Ioannis; Roth, Michael; Tamm, Michael; Stolz, Daiana

    2016-03-01

    Acute exacerbations of COPD (AECOPDs) are associated with accelerated aggravation of clinical symptoms and deterioration of pulmonary function. The mechanisms by which exacerbations may contribute to airway remodeling and declined lung function are poorly understood. We investigated whether AECOPDs are associated with differential expression of glycosaminoglycans in BAL in a cohort of 97 patients with COPD. Patients with COPD with either stable disease (n = 53) or AECOPD (n = 44) and undergoing diagnostic bronchoscopy were matched for demographics and lung function parameters. Levels of heparan sulfate, chondroitin sulfate, dermatan sulfate, and matrix metalloproteinases (MMPs) in BAL were measured by enzyme-linked immunosorbent assay. Heparan sulfate and chondroitin sulfate were significantly increased in BAL of patients during exacerbations. Levels of heparan sulfate were higher in the BAL of patients with microbial infections. Chondroitin sulfate was negatively correlated with FEV1 % predicted but not with diffusing capacity of lung for carbon monoxide % predicted, indicating that chondroitin sulfate is associated with airway remodeling, leading to obstruction rather than to emphysema. Furthermore, heparan sulfate and chondroitin sulfate were significantly correlated with MMP-9, MMP-2, and MMP-12 in BAL, indicating that they were cleaved from their respective proteoglycans by MMPs and subsequently washed out in BAL. During AECOPD, there is increased expression of heparan sulfate and chondroitin sulfate in BAL. These molecules are significantly correlated with MMPs in BAL, indicating that they may be associated with airway remodeling and may lead to lung function decline during exacerbations of COPD. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  18. Chondroitin Sulfate Is Indispensable for Pluripotency and Differentiation of Mouse Embryonic Stem Cells

    NASA Astrophysics Data System (ADS)

    Izumikawa, Tomomi; Sato, Ban; Kitagawa, Hiroshi

    2014-01-01

    Chondroitin sulfate (CS) proteoglycans are present on the surfaces of virtually all cells and in the extracellular matrix and are required for cytokinesis at early developmental stages. Studies have shown that heparan sulfate (HS) is essential for maintaining mouse embryonic stem cells (ESCs) that are primed for differentiation, whereas the function of CS has not yet been elucidated. To clarify the role of CS, we generated glucuronyltransferase-I-knockout ESCs lacking CS. We found that CS was required to maintain the pluripotency of ESCs and promoted initial ESC commitment to differentiation compared with HS. In addition, CS-A and CS-E polysaccharides, but not CS-C polysaccharides, bound to E-cadherin and enhanced ESC differentiation. Multiple-lineage differentiation was inhibited in chondroitinase ABC-digested wild-type ESCs. Collectively, these results suggest that CS is a novel determinant in controlling the functional integrity of ESCs via binding to E-cadherin.

  19. Biosynthesis and function of chondroitin sulfate.

    PubMed

    Mikami, Tadahisa; Kitagawa, Hiroshi

    2013-10-01

    Chondroitin sulfate proteoglycans (CSPGs) are principal pericellular and extracellular components that form regulatory milieu involving numerous biological and pathophysiological phenomena. Diverse functions of CSPGs can be mainly attributed to structural variability of their polysaccharide moieties, chondroitin sulfate glycosaminoglycans (CS-GAG). Comprehensive understanding of the regulatory mechanisms for CS biosynthesis and its catabolic processes is required in order to understand those functions. Here, we focus on recent advances in the study of enzymatic regulatory pathways for CS biosynthesis including successive modification/degradation, distinct CS functions, and disease phenotypes that have been revealed by perturbation of the respective enzymes in vitro and in vivo. Fine-tuned machineries for CS production/degradation are crucial for the functional expression of CS chains in developmental and pathophysiological processes. Control of enzymes responsible for CS biosynthesis/catabolism is a potential target for therapeutic intervention for the CS-associated disorders. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Effect of proteoglycans at interfaces as related to location, architecture, and mechanical cues

    DOE PAGES

    Kurylo, Michael P.; Grandfield, Kathryn; Marshall, Grayson W.; ...

    2015-12-03

    Covalently bound functional GAGs orchestrate tissue mechanics through time-dependent characteristics. The role of specific glycosaminoglycans (GAGs) at the ligament-cementum and cementum-dentin interfaces within a human periodontal complex were examined. Matrix swelling and resistance to compression under health and modeled diseased states was investigated. The presence of keratin sulfate (KS) and chondroitin sulfate (CS) GAGs at the ligament-cementum and cementum-dentin interfaces in human molars (N = 5) was illustrated by using enzymes, atomic force microscopy (AFM), and AFM-based nanoindentation. Furthermore, the change in physical characteristics of modeled diseased states through sequential digestion of keratin sulfate (KS) and chondroitin sulfate (CS) GAGsmore » was investigated. One-way ANOVA tests with P < 0.05 were performed to determine significant differences between groups. Additionally, the presence of mineral within the seemingly hygroscopic interfaces was investigated using transmission electron microscopy. Immunohistochemistry (N = 3) indicated presence of biglycan and fibromodulin small leucine rich proteoglycans at the interfaces. Digestion of matrices with enzymes confirmed the presence of KS and CS GAGs at the interfaces by illustrating a change in ti ssue architecture and mechanics. A significant increase in height (nm), decrease in elastic modulus (GPa), and tissue deformation rate (nm/s) of the PDL-C attachment site (215 ± 63-424 ± 94 nm; 1.5 ± 0.7-0.4 ± 0.2 GPa; 21 ± 7-48 ± 22 nm/s), and cementum-dentin interface (122 ± 69-360 ± 159 nm; 2.9 ± 1.3-0.7 ± 0.3 GPa; 18 ± 4-30 ± 6 nm/s) was observed. The sequential removal of GAGs indicated loss in intricate structural hierarchy of hygroscopic interfaces. From a mechanics perspective, GAGs provide tissue recovery/resilience. Our results provide insights into the role of GAGs toward conserved tooth movement in the socket in response to mechanical loads, and modulation of potentially deleterious strain at tissue interfaces.« less

  1. Oncofetal Chondroitin Sulfate Glycosaminoglycans Are Key Players in Integrin Signaling and Tumor Cell Motility.

    PubMed

    Clausen, Thomas Mandel; Pereira, Marina Ayres; Al Nakouzi, Nader; Oo, Htoo Zarni; Agerbæk, Mette Ø; Lee, Sherry; Ørum-Madsen, Maj Sofie; Kristensen, Anders Riis; El-Naggar, Amal; Grandgenett, Paul M; Grem, Jean L; Hollingsworth, Michael A; Holst, Peter J; Theander, Thor; Sorensen, Poul H; Daugaard, Mads; Salanti, Ali

    2016-12-01

    Many tumors express proteoglycans modified with oncofetal chondroitin sulfate glycosaminoglycan chains (ofCS), which are normally restricted to the placenta. However, the role of ofCS in cancer is largely unknown. The function of ofCS in cancer was analyzed using the recombinant ofCS-binding VAR2CSA protein (rVAR2) derived from the malaria parasite, Plasmodium falciparum We demonstrate that ofCS plays a key role in tumor cell motility by affecting canonical integrin signaling pathways. Binding of rVAR2 to tumor cells inhibited the interaction of cells with extracellular matrix (ECM) components, which correlated with decreased phosphorylation of Src kinase. Moreover, rVAR2 binding decreased migration, invasion, and anchorage-independent growth of tumor cells in vitro Mass spectrometry of ofCS-modified proteoglycan complexes affinity purified from tumor cell lines on rVAR2 columns revealed an overrepresentation of proteins involved in cell motility and integrin signaling, such as integrin-β1 (ITGB1) and integrin-α4 (ITGA4). Saturating concentrations of rVAR2 inhibited downstream integrin signaling, which was mimicked by knockdown of the core chondroitin sulfate synthesis enzymes β-1,3-glucuronyltransferase 1 (B3GAT1) and chondroitin sulfate N-acetylgalactosaminyltransferase 1 (CSGALNACT1). The ofCS modification was highly expressed in both human and murine metastatic lesions in situ and preincubation or early intravenous treatment of tumor cells with rVAR2 inhibited seeding and spreading of tumor cells in mice. This was associated with a significant increase in survival of the animals. These data functionally link ofCS modifications with cancer cell motility and further highlights ofCS as a novel therapeutic cancer target. The cancer-specific expression of ofCS aids in metastatic phenotypes and is a candidate target for therapy. Mol Cancer Res; 14(12); 1288-99. ©2016 AACR. ©2016 American Association for Cancer Research.

  2. Direct Peptide Interaction with Surface Glycosaminoglycans Contributes to the Cell Penetration of Maurocalcine*

    PubMed Central

    Ram, Narendra; Aroui, Sonia; Jaumain, Emilie; Bichraoui, Hicham; Mabrouk, Kamel; Ronjat, Michel; Lortat-Jacob, Hugues; De Waard, Michel

    2008-01-01

    Maurocalcine (MCa), initially identified from a tunisian scorpion venom, defines a new member of the family of cell penetrating peptides by its ability to efficiently cross the plasma membrane. The initiating mechanistic step required for the cell translocation of a cell penetrating peptide implicates its binding onto cell surface components such as membrane lipids and/or heparan sulfate proteoglycans. Here we characterized the interaction of wild-type MCa and MCa K20A, a mutant analogue with reduced cell-penetration efficiency, with heparin (HP) and heparan sulfates (HS) through surface plasma resonance. HP and HS bind both to MCa, indicating that heparan sulfate proteoglycans may represent an important entry route of the peptide. This is confirmed by the fact that (i) both compounds bind with reduced affinity to MCa K20A and (ii) the cell penetration of wild-type or mutant MCa coupled to fluorescent streptavidin is reduced by about 50% in mutant Chinese hamster ovary cell lines lacking either all glycosaminoglycans (GAGs) or just HS. Incubating MCa with soluble HS, HP, or chondroitin sulfates also inhibits the cell penetration of MCa-streptavidin complexes. Analyses of the cell distributions of MCa/streptavidin in several Chinese hamster ovary cell lines show that the distribution of the complex coincides with the endosomal marker Lyso-Tracker red and is not affected by the absence of GAGs. The distribution of MCa/streptavidin is not coincident with that of transferrin receptors nor affected by a dominant-negative dynamin 2 K44A mutant, an inhibitor of clathrin-mediated endocytosis. However, entry of the complex is greatly diminished by amiloride, indicating the importance of macropinocytosis in MCa/streptavidin entry. It is concluded that (i) interaction of MCa with GAGs quantitatively improves the cell penetration of MCa, and (ii) GAG-dependent and -independent MCa penetration rely similarly on the macropinocytosis pathway. PMID:18603532

  3. Early Transcriptional Responses of HepG2-A 16 Liver Cells to Infection by Plasmodium falciparum Sporozoites

    DTIC Science & Technology

    2011-07-29

    not wild-type sporozoites. Glypican-3 is a heparin sulfate proteoglycan (46) secreted in the plasma of hepatocellular carcinoma patients, and...regarded as a diagnostic serum marker for hepatocellular carcinoma (47-50). Unlike wild-type sporozoites, irradiated sporozoites are believed to invade...effector cells other than Kupffer cells. Expression of glypican-3 is known to stimulate the recruitment of macrophages into human hepatocellular

  4. Chondrocyte Culture in Three Dimensional Alginate Sulfate Hydrogels Promotes Proliferation While Maintaining Expression of Chondrogenic Markers

    PubMed Central

    Mhanna, Rami; Kashyap, Aditya; Palazzolo, Gemma; Vallmajo-Martin, Queralt; Becher, Jana; Möller, Stephanie; Schnabelrauch, Matthias

    2014-01-01

    The loss of expression of chondrogenic markers during monolayer expansion remains a stumbling block for cell-based treatment of cartilage lesions. Here, we introduce sulfated alginate hydrogels as a cartilage biomimetic biomaterial that induces cell proliferation while maintaining the chondrogenic phenotype of encapsulated chondrocytes. Hydroxyl groups of alginate were converted to sulfates by incubation with sulfur trioxide–pyridine complex (SO3/pyridine), yielding a sulfated material cross-linkable with calcium chloride. Passage 3 bovine chondrocytes were encapsulated in alginate and alginate sulfate hydrogels for up to 35 days. Cell proliferation was five-fold higher in alginate sulfate compared with alginate (p=0.038). Blocking beta1 integrins in chondrocytes within alginate sulfate hydrogels significantly inhibited proliferation (p=0.002). Sulfated alginate increased the RhoA activity of chondrocytes compared with unmodified alginate, an increase that was blocked by β1 blocking antibodies (p=0.017). Expression and synthesis of type II collagen, type I collagen, and proteoglycan was not significantly affected by the encapsulation material evidenced by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. Alginate sulfate constructs showed an opaque appearance in culture, whereas the unmodified alginate samples remained translucent. In conclusion, alginate sulfate provides a three dimensional microenvironment that promotes both chondrocyte proliferation and maintenance of the chondrogenic phenotype and represents an important advance for chondrocyte-based cartilage repair therapies providing a material in which cell expansion can be done in situ. PMID:24320935

  5. Adeno-associated virus type 2 binding study on model heparan sulfate surface

    NASA Astrophysics Data System (ADS)

    Negishi, Atsuko; Liu, Jian; McCarty, Douglas; Samulski, Jude; Superfine, Richard

    2003-11-01

    Understanding the mechanisms involved in virus infections is useful in its application in areas such as gene therapy, drug development and delivery, and biosensors. In collaboration with UNC Gene Therapy Center and School of Pharmacy, we are specifically looking at the interaction between human parvovirus adeno-associated virus type 2 (AAV2), a potential viral vector, and heparan sulfate proteoglycan (HSPG), a known cell surface receptor for AAV2. Recent development in glycobiology has shown that some protein-polysaccharide binding is sugar sequence dependent. Heparan sulfate (HS) is a polysaccharide chain of sulfated iduronic/glucuronic and sulfate glucosamine residues and can be differentiated into sequence specific structures by enzymes. These enzymatic modifications, known as heparan sulfate sulfotransferase modified modifications, have been shown to change the biological nature of heparan sulfate such as specific binding to proteins and viruses. For understanding HS-assisted viral infection mechanisms, we are interested in investigating the binding affinity and stability of AAV to different HS structures. We have developed a model heparan sulfate surface in which AAV adsorption studies are done and analyzed using the atomic force microscope (AFM). In addition, a miniArray assay has been created to facilitate to this study. Adsorption studies are done in 4 white LED wells with approximately 3 mm2 reaction areas which minimize sample use and waste.

  6. Glycosaminoglycan levels in dried blood spots of patients with mucopolysaccharidoses and mucolipidoses

    PubMed Central

    Kubaski, Francyne; Suzuki, Yasuyuki; Orii, Kenji; Giugliani, Roberto; Church, Heather J.; Mason, Robert W.; Dũng, Vũ Chí; Ngoc, Can Thi Bich; Yamaguchi, Seiji; Kobayashi, Hironori; Girisha, Katta M.; Fukao, Toshiyuki; Orii, Tadao; Tomatsu, Shunji

    2017-01-01

    Mucopolysaccharidoses (MPSs) and mucolipidoses (ML) are groups of lysosomal storage disorders in which lysosomal hydrolases are deficient leading to accumulation of undegraded glycosaminoglycans (GAGs), throughout the body, subsequently resulting in progressive damage to multiple tissues and organs. Assays using tandem mass spectrometry (MS/MS) have been established to measure GAGs in serum or plasma from MPS and ML patients, but few studies were performed to determine whether these assays are sufficiently robust to measure GAG levels in dried blood spots (DBS) of patients with MPS and ML. Material and methods In this study, we evaluated GAG levels in DBS samples from 124 MPS and ML patients (MPS I = 16; MPS II = 21; MPS III = 40; MPS IV = 32; MPS VI =10; MPS VII = 1; ML= 4), and compared them with 115 age-matched controls. Disaccharides were produced from polymer GAGs by digestion with chondroitinase B, heparitinase, and keratanase II. Subsequently, dermatan sulfate (DS), heparan sulfate (HS-0S, HS-NS), and keratan sulfate (mono-sulfated KS, di-sulfated KS, and ratio of di-sulfated KS in total KS) were measured by MS/MS. Results Untreated patients with MPS I, II, VI, and ML had higher levels of DS compared to control samples. Untreated patients with MPS I, II, III, VI, and ML had higher levels of HS-0S; and untreated patients with MPS II, III and VI and ML had higher levels of HS-NS. Levels of KS were age dependent, so although levels of both mono-sulfated KS and di-sulfated KS were generally higher in patients, particularly for MPS II and MPS IV, age group numbers were not sufficient to determine significance of such changes. However, the ratio of di-sulfated KS in total KS was significantly higher in all MPS patients younger than 5 years old, compared to age-matched controls. MPS I and VI patients treated with HSCT had normal levels of DS, and MPS I, VI, and VII treated with ERT or HSCT had normal levels of HS-0S and HS-NS, indicating that both treatments are effective in decreasing blood GAG levels. Conclusion Measurement of GAG levels in DBS is useful for diagnosis and potentially for monitoring the therapeutic efficacy in MPS. PMID:28065440

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ito, Gen; Kobayashi, Takeshi; Takeda, Yoshie

    Highlights: • Proteoglycan from salmon nasal cartridge (SNC-PG) promoted wound healing in fibroblast monolayers. • SNC-PG stimulated both cell proliferation and cell migration. • Interaction between chondroitin sulfate-units and CD44 is responsible for the effect. - Abstract: Proteoglycans (PGs) are involved in various cellular functions including cell growth, adhesion, and differentiation; however, their physiological roles are not fully understood. In this study, we examined the effect of PG purified from salmon nasal cartilage (SNC-PG) on wound closure using tissue-cultured cell monolayers, an in vitro wound-healing assay. The results indicated that SNC-PG significantly promoted wound closure in NIH/3T3 cell monolayers bymore » stimulating both cell proliferation and cell migration. SNC-PG was effective in concentrations from 0.1 to 10 μg/ml, but showed much less effect at higher concentrations (100–1000 μg/ml). The effect of SNC-PG was abolished by chondroitinase ABC, indicating that chondroitin sulfates (CSs), a major component of glycosaminoglycans (GAGs) in SNC-PG, are crucial for the SNC-PG effect. Furthermore, chondroitin 6-sulfate (C-6-S), a major CS of SNC-PG GAGs, could partially reproduce the SNC-PG effect and partially inhibit the binding of SNC-PG to cells, suggesting that SNC-PG exerts its effect through an interaction between the GAGs in SNC-PG and the cell surface. Neutralization by anti-CD44 antibodies or CD44 knockdown abolished SNC-PG binding to the cells and the SNC-PG effect on wound closure. These results suggest that interactions between CS-rich GAG-chains of SNC-PG and CD44 on the cell surface are responsible for the SNC-PG effect on wound closure.« less

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Quantock,A.; Boote, C.; Young, R.

    In the cornea of the eye light transmission is facilitated by the regular arrangement and uniform diameter of collagen fibrils that constitute the bulk of the extracellular corneal matrix. Matrix architecture, in turn, is believed to be governed by interactions between collagen fibrils and proteoglycan molecules modified with sulfated glycosaminoglycan side chains. Here, we outline the contribution made by small-angle X-ray scattering studies of the cornea in understanding the role of sulfated glycosaminoglycans in the control of collagen architecture in cornea, and present new depth-profiled microbeam data from swollen human eye-bank corneas that indicate no significant change in collagen fibrilmore » diameter throughout the tissue, but a lower collagen interfibrillar spacing in the anterior-most stromal regions compared with the ultrastructure of the deeper cornea.« less

  9. Agrin is a major heparan sulfate proteoglycan in the human glomerular basement membrane.

    PubMed

    Groffen, A J; Ruegg, M A; Dijkman, H; van de Velden, T J; Buskens, C A; van den Born, J; Assmann, K J; Monnens, L A; Veerkamp, J H; van den Heuvel, L P

    1998-01-01

    Agrin is a heparan sulfate proteoglycan (HSPG) that is highly concentrated in the synaptic basal lamina at the neuromuscular junction (NMJ). Agrin-like immunoreactivity is also detected outside the NMJ. Here we show that agrin is a major HSPG component of the human glomerular basement membrane (GBM). This is in addition to perlecan, a previously characterized HSPG of basement membranes. Antibodies against agrin and against an unidentified GBM HSPG produced a strong staining of the GBM and the NMJ, different from that observed with anti-perlecan antibodies. In addition, anti-agrin antisera recognized purified GBM HSPG and competed with an anti-GBM HSPG monoclonal antibody in ELISA. Furthermore, both antibodies recognized a molecule that migrated in SDS-PAGE as a smear and had a molecular mass of approximately 200-210 kD after deglycosylation. In immunoelectron microscopy, agrin showed a linear distribution along the GBM and was present throughout the width of the GBM. This was again different from perlecan, which was exclusively present on the endothelial side of the GBM and was distributed in a nonlinear manner. Quantitative ELISA showed that, compared with perlecan, the agrin-like GBM HSPG showed a sixfold higher molarity in crude glomerular extract. These results show that agrin is a major component of the GBM, indicating that it may play a role in renal ultrafiltration and cell matrix interaction. (J Histochem Cytochem 46:19-27, 1998)

  10. Down-regulation of fibroblast growth factor 2 and its co-receptors heparan sulfate proteoglycans by resveratrol underlies the improvement of cardiac dysfunction in experimental diabetes.

    PubMed

    Strunz, Célia Maria Cássaro; Roggerio, Alessandra; Cruz, Paula Lázara; Pacanaro, Ana Paula; Salemi, Vera Maria Cury; Benvenuti, Luiz Alberto; Mansur, Antonio de Pádua; Irigoyen, Maria Cláudia

    2017-02-01

    Cardiac remodeling in diabetes involves cardiac hypertrophy and fibrosis, and fibroblast growth factor 2 (FGF2) is an important mediator of this process. Resveratrol, a polyphenolic antioxidant, reportedly promotes the improvement of cardiac dysfunction in diabetic rats. However, little information exists linking the amelioration of the cardiac function promoted by resveratrol and the expression of FGF2 and its co-receptors, heparan sulfate proteoglycans (HSPGs: Glypican-1 and Syndecan-4), in cardiac muscle of Type 2 diabetic rats. Diabetes was induced experimentally by the injection of streptozotocin and nicotinamide, and the rats were treated with resveratrol for 6 weeks. According to our results, there is an up-regulation of the expression of genes and/or proteins of Glypican-1, Syndecan-4, FGF2, peroxisome proliferator-activated receptor gamma and AMP-activated protein kinase in diabetic rats. On the other hand, resveratrol treatment promoted the attenuation of left ventricular diastolic dysfunction and the down-regulation of the expression of all proteins under study. The trigger for the changes in gene expression and protein synthesis promoted by resveratrol was the presence of diabetes. The negative modulation conducted by resveratrol on FGF2 and HSPGs expression, which are involved in cardiac remodeling, underlies the amelioration of cardiac function. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  11. The spatiotemporal relationships between chondroitin sulfate proteoglycans and terminations of calcitonin gene related peptide and parvalbumin immunoreactive afferents in the spinal cord of mouse embryos.

    PubMed

    Wang, Liqing; Yu, Chao; Wang, Jun; Zhao, Hui; Chan, Sun-On

    2017-08-10

    Chondroitin sulfate (CS) proteoglycans (PGs) are a family of complex molecules in the extracellular matrix and cell surface that regulate axon growth and guidance during development of the central nervous system. In this study, the expression of CSPGs was investigated in the mouse spinal cord at late embryonic and neonatal stages using CS-56 antibody. CS immunoreactivity was observed abundantly in ventral regions of spinal cord of embryonic day (E) 15 embryos. At E16 to E18, CS expression spread dorsally, but never reached the superficial layers of the dorsal horn. This pattern was maintained until postnatal day 4, the latest stage examined. Antibodies against calcitonin gene related peptide (CGRP) and parvalbumin (PV) were employed to label primary afferents from nociceptors and proprioceptors, respectively. CGRP-immunoreactive fibers terminated in the superficial regions of the dorsal horn where CSPGs were weakly expressed, whereas PV-immunoreactive fibers were found in CSPG-rich regions in the ventral horn. Therefore, we conclude that CS expression is spatiotemporally regulated in the spinal cord, which correlates to the termination of sensory afferents. This pattern suggests a role of CSPGs on patterning afferents in the spinal cord, probably through a differential response of axons to these growth inhibitory molecules. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Basement membrane of mouse bone marrow sinusoids shows distinctive structure and proteoglycan composition: a high resolution ultrastructural study.

    PubMed

    Inoue, S; Osmond, D G

    2001-11-01

    Venous sinusoids in bone marrow are the site of a large-scale traffic of cells between the extravascular hemopoietic compartment and the blood stream. The wall of the sinusoids consists solely of a basement membrane interposed between a layer of endothelial cells and an incomplete covering of adventitial cells. To examine its possible structural specialization, the basement membrane of bone marrow sinusoids has now been examined by high resolution electron microscopy of perfusion-fixed mouse bone marrow. The basement membrane layer was discontinuous, consisting of irregular masses of amorphous material within a uniform 60-nm-wide space between apposing endothelial cells and adventitial cell processes. At maximal magnifications, the material was resolved as a random arrangement of components lacking the "cord network" formation seen in basement membranes elsewhere. Individual components exhibited distinctive ultrastructural features whose molecular identity has previously been established. By these morphological criteria, the basement membrane contained unusually abundant chondroitin sulfate proteoglycan (CSPG) revealed by 3-nm-wide "double tracks," and moderate amounts of both laminin as dense irregular coils and type IV collagen as 1-1.5-nm-wide filaments, together with less conspicuous amounts of amyloid P forming pentagonal frames. In contrast, 4.5-5-nm-wide "double tracks" characteristic of heparan sulfate proteoglycan (HSPG) were absent. The findings demonstrate that, in comparison with "typical" basement membranes in other tissues, the bone marrow sinusoidal basement membrane is uniquely specialized in several respects. Its discontinuous nature, lack of network organization, and absence of HSPG, a molecule that normally helps to maintain membrane integrity, may facilitate disassembly and reassembly of basement membrane material in concert with movements of adventitial cell processes as maturing hemopoietic cells pass through the sinusoidal wall: the exceptionally large quantity of CSPG may represent a reservoir of CD44 receptor for use in hemopoiesis. Copyright 2001 Wiley-Liss, Inc.

  13. Behavior of sea urchin primary mesenchyme cells in artificial extracellular matrices.

    PubMed

    Katow, H

    1986-02-01

    The primary mesenchyme cells (PMCs) were separated from the mesenchyme blastulae of Pseudocentrotus depressus using differential adhesiveness of these cells to plastic Petri dishes. These cells were incubated in various artificial extracellular matrices (ECMs) including horse serum plasma fibronectin, mouse EHS sarcoma laminin, mouse EHS sarcoma type IV collagen, and porcine skin dermatan sulfate. The cell behavior was monitored by a time-lapse videomicrograph and analysed with a microcomputer. The ultrastructure of the artificial ECM was examined by transmission electron microscopy (TEM), while the ultrastructure of the PMCs was examined by scanning electron microscopy (SEM). The PMCs did not migrate in type IV collagen gel, laminin or dermatan sulfate matrix either with or without collagen gel, whereas PMCs in the matrix which was composed of fibronectin and collagen gel migrated considerably. However, the most active and extensive PMC migration was seen in the matrix which contained dermatan sulfate in addition to fibronectin and collagen gel. This PMC migration involved an increase not only of migration speed but also of proportion of migration-promoted cells. These results support the hypothesis that the mechanism of PMC migration involves fibronectin, collagen and sulfated proteoglycans which contain dermatan sulfate.

  14. The Location-Specific Role of Proteoglycans in the Flexor Carpi Ulnaris Tendon

    PubMed Central

    Buckley, Mark R.; Huffman, George R.; Iozzo, Renato V.; Birk, David E.; Soslowsky, Louis J.

    2015-01-01

    Tendons like the flexor carpi ulnaris (FCU) that contain region-specific distributions of proteoglycans (PGs) as a result of the heterogeneous, multi-axial loads they are subjected to in vivo provide valuable models for understanding structure-function relationships in connective tissues. However, the contributions of specific PGs to FCU tendon mechanical properties are unknown. Therefore, the objective of this study was to determine how the location-dependent, viscoelastic mechanical properties of the FCU tendon are impacted individually by PG-associated glycosaminoglycans (GAGs) and by two small leucine-rich proteoglycans (SLRPs), biglycan and decorin. Full length FCU tendons from biglycan- and decorin-null mice were compared to wild type mice to evaluate the effects of specific SLRPs, while chondroitinase ABC digestion of isolated specimens removed from the tendon midsubstance was used to determine how chontroitin/dermatan sulfate (CS/DS) GAGs impact mechanics in mature FCU tendons. A novel combined genetic knockout/ digestion technique also was employed to compare SLRP-null and wild-type tendons in the absence of CS/DS GAGs that may impact properties in the mature state. In all genotypes, mechanical properties in the FCU tendon midsubstance were not affected by GAG digestion. Full-length tendons exhibited complex, multi-axial deformation under tension that may be associated with their in vivo loading environment. Mechanical properties were adversely affected by the absence of biglycan, and a decreased modulus localized in the center of the tendon was measured. These results help elucidate the role that local alterations in proteoglycan levels may play in processes that adversely impact tendon functionality including injury and pathology. PMID:23941206

  15. "Coding" and "Decoding": hypothesis for the regulatory mechanism involved in heparan sulfate biosynthesis.

    PubMed

    Zhang, Xu; Wang, Fengshan; Sheng, Juzheng

    2016-06-16

    Heparan sulfate (HS) is widely distributed in mammalian tissues in the form of HS proteoglycans, which play essential roles in various physiological and pathological processes. In contrast to the template-guided processes involved in the synthesis of DNA and proteins, HS biosynthesis is not believed to involve a template. However, it appears that the final structure of HS chains was strictly regulated. Herein, we report research based hypothesis that two major steps, namely "coding" and "decoding" steps, are involved in the biosynthesis of HS, which strictly regulate its chemical structure and biological activity. The "coding" process in this context is based on the distribution of sulfate moieties on the amino groups of the glucosamine residues in the HS chains. The sulfation of these amine groups is catalyzed by N-deacetylase/N-sulfotransferase, which has four isozymes. The composition and distribution of sulfate groups and iduronic acid residues on the glycan chains of HS are determined by several other modification enzymes, which can recognize these coding sequences (i.e., the "decoding" process). The degree and pattern of the sulfation and epimerization in the HS chains determines the extent of their interactions with several different protein factors, which further influences their biological activity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Effect of Dermatan Sulfate on the Indentation and Tensile Properties of Articular Cartilage

    PubMed Central

    Hall, Melanie L.; Krawczak, David A.; Simha, Narendra K.; Lewis, Jack L.

    2009-01-01

    Objective This paper examines the hypothesis that the dermatan sulfate (DS) chain on decorin is a load carrying element in cartilage and that its damage or removal will alter the material properties. Methods To test this hypothesis, indentation and tensile testing of cartilage from bovine patella was performed before and after digestion with chondroitinase B (cB). Removal of significant amounts of DS by cB digestion was verified by Western blot analysis of proteoglycans extracted from whole and sectioned specimens. Specimens (control and treated) were subjected to a series of step-hold displacements. Elastic modulus during the step rise (rapid modulus) and at equilibrium (equilibrium modulus), and the relaxation function during each step were measured for test (cB and buffer) and control (buffer alone) conditions. Results cB had no effect on any of the viscoelastic mechanical properties measured, either in indentation or tension Conclusion Removing or damaging approximately 50% of the dermatan sulfate had no effect on the mechanical properties, strongly suggesting that dermatan sulfate either carries very low load or no load. PMID:19036614

  17. Molecular dissection of placental malaria protein VAR2CSA interaction with a chemo-enzymatically synthesized chondroitin sulfate library.

    PubMed

    Sugiura, Nobuo; Clausen, Thomas Mandel; Shioiri, Tatsumasa; Gustavsson, Tobias; Watanabe, Hideto; Salanti, Ali

    2016-12-01

    Placental malaria, a serious infection caused by the parasite Plasmodium falciparum, is characterized by the selective accumulation of infected erythrocytes (IEs) in the placentas of the pregnant women. Placental adherence is mediated by the malarial VAR2CSA protein, which interacts with chondroitin sulfate (CS) proteoglycans present in the placental tissue. CS is a linear acidic polysaccharide composed of repeating disaccharide units of D-glucuronic acid and N-acetyl-D-galactosamine that are modified by sulfate groups at different positions. Previous reports have shown that placental-adhering IEs were associated with an unusually low sulfated form of chondroitin sulfate A (CSA) and that a partially sulfated dodecasaccharide is the minimal motif for the interaction. However, the fine molecular structure of this CS chain remains unclear. In this study, we have characterized the CS chain that interacts with a recombinant minimal CS-binding region of VAR2CSA (rVAR2) using a CS library of various defined lengths and sulfate compositions. The CS library was chemo-enzymatically synthesized with bacterial chondroitin polymerase and recombinant CS sulfotransferases. We found that C-4 sulfation of the N-acetyl-D-galactosamine residue is critical for supporting rVAR2 binding, whereas no other sulfate modifications showed effects. Interaction of rVAR2 with CS is highly correlated with the degree of C-4 sulfation and CS chain length. We confirmed that the minimum structure binding to rVAR2 is a tri-sulfated CSA dodecasaccharide, and found that a highly sulfated CSA eicosasaccharide is a more potent inhibitor of rVAR2 binding than the dodecasaccharides. These results suggest that CSA derivatives may potentially serve as targets in therapeutic strategies against placental malaria.

  18. A Better Way to Excise Inhibitory Molecules (CSPGs) from a Spinal Cord Injury Scar to Promote Regeneration

    DTIC Science & Technology

    2013-10-01

    556. 41. Zhang, G. ,R.-L. Lin, M. Wiggers, D.M. Snow, and L.-Y. Lee (2008) Altered expression of TRPV1 and sensitivity to capsaicin in pulmonary...chondroitin sulfate proteoglycans in vitro focusing on cortical astrocytes interactions with sensory neurons. "Role of TRPV1 in Airway Hypersensitivity...Aims: To investigate the role of TRPV1 in the development of airway hypersensitivity when chronic airway inflammation is induced by allergen

  19. The Cysteine-Rich Domain of the Macrophage Mannose Receptor Is a Multispecific Lectin That Recognizes Chondroitin Sulfates a and B and Sulfated Oligosaccharides of Blood Group Lewisa and Lewisx Types in Addition to the Sulfated N-Glycans of Lutropin

    PubMed Central

    Leteux, Christine; Chai, Wengang; Loveless, R. Wendy; Yuen, Chun-Ting; Uhlin-Hansen, Lars; Combarnous, Yves; Jankovic, Mila; Maric, Svetlana C.; Misulovin, Ziva; Nussenzweig, Michel C.; Ten Feizi

    2000-01-01

    The mannose receptor (MR) is an endocytic protein on macrophages and dendritic cells, as well as on hepatic endothelial, kidney mesangial, tracheal smooth muscle, and retinal pigment epithelial cells. The extracellular portion contains two types of carbohydrate-recognition domain (CRD): eight membrane-proximal C-type CRDs and a membrane-distal cysteine-rich domain (Cys-MR). The former bind mannose-, N-acetylglucosamine-, and fucose-terminating oligosaccharides, and may be important in innate immunity towards microbial pathogens, and in antigen trapping for processing and presentation in adaptive immunity. Cys-MR binds to the sulfated carbohydrate chains of pituitary hormones and may have a role in hormonal clearance. A second feature of Cys-MR is binding to macrophages in marginal zones of the spleen, and to B cell areas in germinal centers which may help direct MR-bearing cells toward germinal centers during the immune response. Here we describe two novel classes of carbohydrate ligand for Cys-MR: chondroitin-4 sulfate chains of the type found on proteoglycans produced by cells of the immune system, and sulfated blood group chains. We further demonstrate that Cys-MR interacts with cells in the spleen via the binding site for sulfated carbohydrates. Our data suggest that the three classes of sulfated carbohydrate ligands may variously regulate the trafficking and function of MR-bearing cells. PMID:10748230

  20. Effects of exercise on knee joints with osteoarthritis: a pilot study of biologic markers

    NASA Technical Reports Server (NTRS)

    Bautch, J. C.; Malone, D. G.; Vailas, A. C.

    1997-01-01

    OBJECTIVE: To determine the effects of low intensity weight-bearing exercise on osteoarthritis (OA) of the knee. METHODS: Synovial fluid keratan sulfate (KS) and hydroxyproline were measured as markers of cartilage degradation. The Arthritis Impact Measurement Scales (AIMS) were used to measure health status, and a visual analog scale for pain assessment was used before and after intervention. An exercise (EX) group (n = 15) received a thrice-weekly 12-week low intensity exercise program and a weekly educational program, and a minimal treatment (Min RX) group (n = 15) received only the education program. RESULTS: Pain levels declined in the EX group, and the Min RX group showed improvement on the AIMS. Synovial fluid was obtained in 11 subjects before and after the intervention. Levels of KS and hydroxyproline did not change. CONCLUSION: Further study of exercise effects should include both clinical and biologic parameters to examine the outcome of exercise as a therapeutic intervention in OA of the knee.

  1. Can we produce heparin/heparan sulfate biomimetics using "mother-nature" as the gold standard?

    PubMed

    Farrugia, Brooke L; Lord, Megan S; Melrose, James; Whitelock, John M

    2015-03-05

    Heparan sulfate (HS) and heparin are glycosaminoglycans (GAGs) that are heterogeneous in nature, not only due to differing disaccharide combinations, but also their sulfate modifications. HS is well known for its interactions with various growth factors and cytokines; and heparin for its clinical use as an anticoagulant. Due to their potential use in tissue regeneration; and the recent adverse events due to contamination of heparin; there is an increased surge to produce these GAGs on a commercial scale. The production of HS from natural sources is limited so strategies are being explored to be biomimetically produced via chemical; chemoenzymatic synthesis methods and through the recombinant expression of proteoglycans. This review details the most recent advances in the field of HS/heparin synthesis for the production of low molecular weight heparin (LMWH) and as a tool further our understanding of the interactions that occur between GAGs and growth factors and cytokines involved in tissue development and repair.

  2. Permeability of the Peritrophic Envelopes of Herbivorous Insects to Dextran Sulfate: a Test of the Polyanion Exclusion Hypothesis.

    PubMed

    MARTIN, M M.; BARBEHENN, R V.

    1997-03-01

    We tested the hypothesis that the permeability of the peritrophic envelope in herbivorous insects is greatly reduced for polyanions as a result of an extensive network of anionic sites in the proteoglycans of the matrix. 14C-Dextran sulfate (polyanionic, 8000 M(w)) and fluorescein isothiocyanate-labeled (FITC) dextran (monoanionic, 9400 M(w)) were introduced together into the endoperitrophic space of the midguts of Orgyia leucostigma (Lepidoptera) larvae and Melanoplus sanguinipes (Orthoptera) adults. In all cases more of the 14C-dextran sulfate permeated the peritrophic envelope than the FITC-dextran, the opposite of the result predicted by the polyanion exclusion hypothesis. We conclude that polyanion exclusion is not a mechanism that contributes significantly to the permeability properties of the peritrophic envelopes of these two species, or that explains the failure of tannic acid to cross the peritrophic envelopes of lepidopteran larvae. Copyright 1997 Elsevier Science Ltd. All rights reserved

  3. Heparan Sulfates Support Pyramidal Cell Excitability, Synaptic Plasticity, and Context Discrimination

    PubMed Central

    Minge, Daniel; Senkov, Oleg; Kaushik, Rahul; Herde, Michel K.; Tikhobrazova, Olga; Wulff, Andreas B.; Mironov, Andrey; van Kuppevelt, Toin H.; Oosterhof, Arie; Kochlamazashvili, Gaga

    2017-01-01

    Abstract Heparan sulfate (HS) proteoglycans represent a major component of the extracellular matrix and are critical for brain development. However, their function in the mature brain remains to be characterized. Here, acute enzymatic digestion of HS side chains was used to uncover how HSs support hippocampal function in vitro and in vivo. We found that long-term potentiation (LTP) of synaptic transmission at CA3–CA1 Schaffer collateral synapses was impaired after removal of highly sulfated HSs with heparinase 1. This reduction was associated with decreased Ca2+ influx during LTP induction, which was the consequence of a reduced excitability of CA1 pyramidal neurons. At the subcellular level, heparinase treatment resulted in reorganization of the distal axon initial segment, as detected by a reduction in ankyrin G expression. In vivo, digestion of HSs impaired context discrimination in a fear conditioning paradigm and oscillatory network activity in the low theta band after fear conditioning. Thus, HSs maintain neuronal excitability and, as a consequence, support synaptic plasticity and learning. PMID:28119345

  4. Characterization of Glycan Structures of Chondroitin Sulfate-Glycopeptides Facilitated by Sodium Ion-Pairing and Positive Mode LC-MS/MS

    NASA Astrophysics Data System (ADS)

    Nilsson, Jonas; Noborn, Fredrik; Gomez Toledo, Alejandro; Nasir, Waqas; Sihlbom, Carina; Larson, Göran

    2017-02-01

    Purification and liquid chromatography-tandem mass spectrometry (LC-MS/MS) characterization of glycopeptides, originating from protease digests of glycoproteins, enables site-specific analysis of protein N- and O-glycosylations. We have described a protocol to enrich, hydrolyze by chondroitinase ABC, and characterize chondroitin sulfate-containing glycopeptides (CS-glycopeptides) using positive mode LC-MS/MS. The CS-glycopeptides, originating from the Bikunin proteoglycan of human urine samples, had ΔHexAGalNAcGlcAGalGalXyl- O-Ser hexasaccharide structure and were further substituted with 0-3 sulfate and 0-1 phosphate groups. However, it was not possible to exactly pinpoint sulfate attachment residues, for protonated precursors, due to extensive fragmentation of sulfate groups using high-energy collision induced dissociation (HCD). To circumvent the well-recognized sulfate instability, we now introduced Na+ ions to form sodiated precursors, which protected sulfate groups from decomposition and facilitated the assignment of sulfate modifications. Sulfate groups were pinpointed to both Gal residues and to the GalNAc of the hexasaccharide structure. The intensities of protonated and sodiated saccharide oxonium ions were very prominent in the HCD-MS2 spectra, which provided complementary structural analysis of sulfate substituents of CS-glycopeptides. We have demonstrated a considerable heterogeneity of the bikunin CS linkage region. The realization of these structural variants should be beneficial in studies aimed at investigating the importance of the CS linkage region with regards to the biosynthesis of CS and potential interactions to CS binding proteins. Also, the combined use of protonated and sodiated precursors for positive mode HCD fragmentation analysis will likely become useful for additional classes of sulfated glycopeptides.

  5. Proton conductivity in ampullae of Lorenzini jelly

    PubMed Central

    Josberger, Erik E.; Hassanzadeh, Pegah; Deng, Yingxin; Sohn, Joel; Rego, Michael J.; Amemiya, Chris T.; Rolandi, Marco

    2016-01-01

    In 1678, Stefano Lorenzini first described a network of organs of unknown function in the torpedo ray—the ampullae of Lorenzini (AoL). An individual ampulla consists of a pore on the skin that is open to the environment, a canal containing a jelly and leading to an alveolus with a series of electrosensing cells. The role of the AoL remained a mystery for almost 300 years until research demonstrated that skates, sharks, and rays detect very weak electric fields produced by a potential prey. The AoL jelly likely contributes to this electrosensing function, yet the exact details of this contribution remain unclear. We measure the proton conductivity of the AoL jelly extracted from skates and sharks. The room-temperature proton conductivity of the AoL jelly is very high at 2 ± 1 mS/cm. This conductivity is only 40-fold lower than the current state-of-the-art proton-conducting polymer Nafion, and it is the highest reported for a biological material so far. We suggest that keratan sulfate, identified previously in the AoL jelly and confirmed here, may contribute to the high proton conductivity of the AoL jelly with its sulfate groups—acid groups and proton donors. We hope that the observed high proton conductivity of the AoL jelly may contribute to future studies of the AoL function. PMID:27386543

  6. An affinity adsorption media that mimics heparan sulfate proteoglycans for the treatment of drug-resistant bacteremia

    NASA Astrophysics Data System (ADS)

    McCrea, Keith R.; Ward, Robert S.

    2016-06-01

    Removal of several drug-resistant bacteria from blood by affinity adsorption onto a heparin-functional media is reported. Heparin is a chemical analogue of heparan sulfate (HS) proteoglycans, found on transmembrane proteins of endothelial cells. Many blood-borne human pathogens, including bacteria, viruses, parasites, and fungi have been reported to target HS as an initial step in their pathogenesis. Here, we demonstrate the binding and removal of Methicillin-resistant Staphylococcus aureus (MRSA), Extended-Spectrum Betalactamase Klebsiella pneumoniae (ESBL), and two Carbapenem-resistant Enterobacteriaceae (both CRE Escherichia coli and CRE K. pneumoniae) using 300 μm polyethylene beads surface modified with end-point-attached heparin. Depending on the specific bacteria, the amount removed ranged between 39% (ESBL) and 99.9% (CRE). The total amount of bacteria adsorbed ranged between 2.8 × 105 and 8.6 × 105 colony forming units (CFU) per gram of adsorption media. Based on a polymicrobial challenge which showed no competitive binding, MRSA and CRE apparently utilize different binding sequences on the immobilized heparin ligand. Since the total circulating bacterial load during bacteremia seldom exceeds 5 × 105 CFUs, it appears possible to significantly reduce bacterial concentration in infected patients by multi-pass recirculation of their blood through a small extracorporeal affinity filter containing the heparin-functional adsorption media. This 'dialysis-like therapy' is expected to improve patient outcomes and reduce the cost of care, particularly when there are no anti-infective drugs available to treat the infection.

  7. Accumulation of neurocan, a brain chondroitin sulfate proteoglycan, in association with the retinal vasculature in RCS rats.

    PubMed

    Zhang, Yiqin; Rauch, Uwe; Perez, Maria-Thereza R

    2003-03-01

    To examine whether and how the retinal distribution of the chondroitin sulfate proteoglycan neurocan is affected after photoreceptor cell loss and whether it correlates with the multiple secondary cellular changes that accompany the photoreceptor degeneration. Retinas from normal rats (Sprague-Dawley; postnatal days [P]0-P70), RCS rats with dystrophic retinas (P0-P300), RCS-rdy(+) congenic rats with nondystrophic retinas (P0-202), and rhodopsin mutant rats, P23H (P0-P257) and S334ter (P0-P220), were processed for immunohistochemistry using a polyclonal antibody to rat neurocan. The overall distribution of neurocan was similar in all retinas examined. Neurocan immunostaining was detected over the nerve fiber layer, the plexiform layers, the photoreceptor outer segments region, and the ciliary epithelium. With age, labeling throughout the plexiform layers decreased continuously. In RCS rats however, conspicuous labeling was also seen in association with retinal vessels, from P15 onward. Accumulation of neurocan in association with the retinal vasculature does not correlate with photoreceptor cell loss, because it was not observed in the rhodopsin mutant rats. During the earliest stages of the disease, accumulation of debris in the subretinal space in RCS rats may be sufficient per se to initiate a cascade of metabolic changes that result in accumulation of neurocan. With time, the neurocan accumulated perivascularly may, by interaction with other matrix molecules, modulate at least some of the vascular alterations observed in this animal model.

  8. Biomimetic Proteoglycan Interactions with Type I Collagen Investigated via 2D and 3D TEM

    NASA Astrophysics Data System (ADS)

    Moorehead, Carli

    Collagen is one of the leading components in extracellular matrix (ECM), providing durability, structural integrity, and functionality for many tissues. Regulation of collagen fibrillogenesis and degradation is important in the treatment of a number of diseases from orthopedic injuries to genetic deficiencies. Recently, novel, biocompatible, semi-synthetic biomimetic proteoglycans (BPGs) were developed, which consist of an enzymatically resistant synthetic polymer core and natural chondroitin sulfate bristles. It was demonstrated that BPGs affect type I collagen fibrillogenesis in vitro, as reflected by their impact delaying the kinetic formation of gels similar to native PGs. This indicates that the morphology of collagen scaffolds as well as endogenous ECM could also be modulated by these proteoglycan mimics. However, the imaging modality used previously, reflectance confocal microscopy, did not yield the resolution necessary to spatially localize BPGs within the collagen network or investigate the effect of BPGs on the quality of collagen fibrils produced in an in vitro fibrillogenesis model which is important for understanding the method of interaction. Consequently, a histological technique, electron tomography, was adapted and utilized to 3D image the nano-scale structures within this simplified tissue model. BPGs were found to aid in lateral growth and enhance fibril banding periodicity resulting in structures more closely resembling those in tissue, in addition to attaching to the collagen surface despite the lack of a protein core.

  9. Matrix Disruptions, Growth, and Degradation of Cartilage with Impaired Sulfation*

    PubMed Central

    Mertz, Edward L.; Facchini, Marcella; Pham, Anna T.; Gualeni, Benedetta; De Leonardis, Fabio; Rossi, Antonio; Forlino, Antonella

    2012-01-01

    Diastrophic dysplasia (DTD) is an incurable recessive chondrodysplasia caused by mutations in the SLC26A2 transporter responsible for sulfate uptake by chondrocytes. The mutations cause undersulfation of glycosaminoglycans in cartilage. Studies of dtd mice with a knock-in Slc26a2 mutation showed an unusual progression of the disorder: net undersulfation is mild and normalizing with age, but the articular cartilage degrades with age and bones develop abnormally. To understand underlying mechanisms, we studied newborn dtd mice. We developed, verified and used high-definition infrared hyperspectral imaging of cartilage sections at physiological conditions, to quantify collagen and its orientation, noncollagenous proteins, and chondroitin chains, and their sulfation with 6-μm spatial resolution and without labeling. We found that chondroitin sulfation across the proximal femur cartilage varied dramatically in dtd, but not in the wild type. Corresponding undersulfation of dtd was mild in most regions, but strong in narrow articular and growth plate regions crucial for bone development. This undersulfation correlated with the chondroitin synthesis rate measured via radioactive sulfate incorporation, explaining the sulfation normalization with age. Collagen orientation was reduced, and the reduction correlated with chondroitin undersulfation. Such disorientation involved the layer of collagen covering the articular surface and protecting cartilage from degradation. Malformation of this layer may contribute to the degradation progression with age and to collagen and proteoglycan depletion from the articular region, which we observed in mice already at birth. The results provide clues to in vivo sulfation, DTD treatment, and cartilage growth. PMID:22556422

  10. Structure of a fucose-branched chondroitin sulfate from sea cucumber. Evidence for the presence of 3-O-sulfo-beta-D-glucuronosyl residues.

    PubMed

    Vieira, R P; Mulloy, B; Mourão, P A

    1991-07-25

    The structure of a unique focose-branched chondroitin sulfate isolated from the body wall of a sea cucumber was examined in detail. This glycosaminoglycan contains side chain disaccharide units of sulfated fucopyranosyl units linked to approximately one-half of the glucuronic acid moieties through the O-3 position of the acid. The intact polysaccharide is totally resistant to chondroitinase degradation, whereas, after defucosylation, it is partially degraded by the enzyme. However, only after an additional step of desulfation, the chondroitin from sea cucumber is almost totally degraded by chondroitinase AC or ABC. This result, together with the methylation and NMR studies of the native and chemically modified polysaccharide, suggest that besides the fucose branches, the sea cucumber chondroitin sulfate contains sulfate esters at position O-3 of the beta-D-glucuronic acid units. Furthermore, the proteoglycan from the sea cucumber chondroitin sulfate is recognized by anti-Leu-7 monoclonal antibody, which specifically recognizes 3-sulfoglucuronic acid residues. In analogy with the fucose branched units, the 3-O-sulfo-beta-D-glucuronosyl residues are resistant to chondroitinase degradation. Regarding the position of the glycosidic linkage and site of sulfation in the fucose branches, our results suggest high heterogeneity. Tentatively, it is possible to suggest the preponderance of disaccharide units formed by 3,4-di-O-sulfo-alpha-L-fucopyranosyl units glycosidically linked through position 1----2 to 4-O-sulfo-alpha-L-fucopyranose. Finally, the presence of unusual 4/6-disulfated disaccharide units, together with the common 6-sulfated and non-sulfated units, was detected in the chondroitin sulfate core of this polysaccharide.

  11. Synaptogenesis Is Modulated by Heparan Sulfate in Caenorhabditis elegans

    PubMed Central

    Lázaro-Peña, María I.; Díaz-Balzac, Carlos A.; Bülow, Hannes E.; Emmons, Scott W.

    2018-01-01

    The nervous system regulates complex behaviors through a network of neurons interconnected by synapses. How specific synaptic connections are genetically determined is still unclear. Male mating is the most complex behavior in Caenorhabditis elegans. It is composed of sequential steps that are governed by > 3000 chemical connections. Here, we show that heparan sulfates (HS) play a role in the formation and function of the male neural network. HS, sulfated in position 3 by the HS modification enzyme HST-3.1/HS 3-O-sulfotransferase and attached to the HS proteoglycan glypicans LON-2/glypican and GPN-1/glypican, functions cell-autonomously and nonautonomously for response to hermaphrodite contact during mating. Loss of 3-O sulfation resulted in the presynaptic accumulation of RAB-3, a molecule that localizes to synaptic vesicles, and disrupted the formation of synapses in a component of the mating circuits. We also show that the neural cell adhesion protein NRX-1/neurexin promotes and the neural cell adhesion protein NLG-1/neuroligin inhibits the formation of the same set of synapses in a parallel pathway. Thus, neural cell adhesion proteins and extracellular matrix components act together in the formation of synaptic connections. PMID:29559501

  12. Epac1 increases migration of endothelial cells and melanoma cells via FGF2-mediated paracrine signaling

    PubMed Central

    Baljinnyam, Erdene; Umemura, Masanari; Chuang, Christine; De Lorenzo, Mariana S; Iwatsubo, Mizuka; Chen, Suzie; Goydos, James S; Ishikawa, Yoshihiro; Whitelock, John M; Iwatsubo, Kousaku

    2014-01-01

    Fibroblast growth factor (FGF2) regulates endothelial and melanoma cell migration. The binding of FGF2 to its receptor requires N-sulfated heparan sulfate (HS) glycosamine. We have previously reported that Epac1, an exchange protein activated by cAMP, increases N-sulfation of HS in melanoma. Therefore, we examined whether Epac1 regulates FGF2-mediated cell–cell communication. Conditioned medium (CM) of melanoma cells with abundant expression of Epac1 increased migration of human umbilical endothelial cells (HUVEC) and melanoma cells with poor expression of Epac1. CM-induced increase in migration was inhibited by antagonizing FGF2, by the removal of HS and by the knockdown of Epac1. In addition, knockdown of Epac1 suppressed the binding of FGF2 to FGF receptor in HUVEC, and in vivo angiogenesis in melanoma. Furthermore, knockdown of Epac1 reduced N-sulfation of HS chains attached to perlecan, a major secreted type of HS proteoglycan that mediates the binding of FGF2 to FGF receptor. These data suggested that Epac1 in melanoma cells regulates melanoma progression via the HS–FGF2-mediated cell–cell communication. PMID:24725364

  13. The Ndst Gene Family in Zebrafish: Role of Ndst1b in Pharyngeal Arch Formation

    PubMed Central

    Haitina, Tatjana; Habicher, Judith; Ledin, Johan; Kjellén, Lena

    2015-01-01

    Heparan sulfate (HS) proteoglycans are ubiquitous components of the extracellular matrix and plasma membrane of metazoans. The sulfation pattern of the HS glycosaminoglycan chain is characteristic for each tissue and changes during development. The glucosaminyl N-deacetylase/N-sulfotransferase (NDST) enzymes catalyze N-deacetylation and N-sulfation during HS biosynthesis and have a key role in designing the sulfation pattern. We here report on the presence of five NDST genes in zebrafish. Zebrafish ndst1a, ndst1b, ndst2a and ndst2b represent duplicated mammalian orthologues of NDST1 and NDST2 that arose through teleost specific genome duplication. Interestingly, the single zebrafish orthologue ndst3, is equally similar to tetrapod Ndst3 and Ndst4. It is likely that a local duplication in the common ancestor of lobe-finned fish and tetrapods gave rise to these two genes. All zebrafish Ndst genes showed distinct but partially overlapping expression patterns during embryonic development. Morpholino knockdown of ndst1b resulted in delayed development, craniofacial cartilage abnormalities, shortened body and pectoral fin length, resembling some of the features of the Ndst1 mouse knockout. PMID:25767878

  14. Diagnosis of Morquio Syndrome in Dried Blood Spots Based on a New MRM-MS Assay.

    PubMed

    Cozma, Claudia; Eichler, Sabrina; Wittmann, Gyula; Flores Bonet, Alba; Kramp, Guido Johannes; Giese, Anne-Katrin; Rolfs, Arndt

    2015-01-01

    Mucopolysaccharidosis IVA (MPS IVA; Morquio A disease) is an autosomal recessive disease caused and characterized by a decreased activity of N-acetylgalactosamine-6-sulfate sulfatase (GALNS), resulting in accumulation of keratan sulfate and chondroitin-6-sulfate in tissues and secondary organ damage. Recently approved enzyme replacement therapy renders the easy and early identification of MPS IVA of out-most importance. We propose a completely new assay for the stable and reproducible detection of GALNS deficiency in dry blood spots (DBS). For the validation blood samples were taken from 59 healthy individuals and 24 randomly selected genetically confirmed MPS IVA patients. The material extracted from DBS was incubated with a 4-methylumbelliferyl-β-D-galactopyranoside-6-sulfate as a specific substrate. Final enzymatic product, 4-methylumbelliferone, obtained after adding exogenous beta-galactosidase, was quantified by LC/MRM-MS (liquid-chromatography/multiple-reaction-monitoring mass-spectrometry). 4-propyl-5-hydroxy-7-methyl-2h-chromen-2-one was used as internal standard, a compound with a similar molecular structure and fragmentation pattern in negative ion mode as 4-methylumbelliferone. The enzymatic assay yielded a positive and negative predictive value of 1.0 for genetically confirmed MPS IVA patients (GALNS activity of 0.35 ± 0.21 μmol/L/h) and for controls with normal GALNS activity (23.1 ± 5.3 μmol/L /h). With present enzymatic conditions, the reaction yield in dried blood spots is at least 20 fold higher than any previously reported data with other assays. The present LC/MRM-MS based assay for MPS IVA diagnosis provides an easy, highly-standardized, accurate and innovative quantification of the enzymatic product in vitro and distinguishes perfectly between MPS IVA affected patients and normal controls. This technique will significantly simplify the early detection of MPS IVA patients.

  15. The Tyrosine Sulfate Domain of Fibromodulin Binds Collagen and Enhances Fibril Formation.

    PubMed

    Tillgren, Viveka; Mörgelin, Matthias; Önnerfjord, Patrik; Kalamajski, Sebastian; Aspberg, Anders

    2016-11-04

    Small leucine-rich proteoglycans interact with other extracellular matrix proteins and are important regulators of matrix assembly. Fibromodulin has a key role in connective tissues, binding collagen through two identified binding sites in its leucine-rich repeat domain and regulating collagen fibril formation in vitro and in vivo Some nine tyrosine residues in the fibromodulin N-terminal domain are O-sulfated, a posttranslational modification often involved in protein interactions. The N-terminal domain mimics heparin, binding proteins with clustered basic amino acid residues. Because heparin affects collagen fibril formation, we investigated whether tyrosine sulfate is involved in fibromodulin interactions with collagen. Using full-length fibromodulin and its N-terminal tyrosine-sulfated domain purified from tissue, as well as recombinant fibromodulin fragments, we found that the N-terminal domain binds collagen. The tyrosine-sulfated domain and the leucine-rich repeat domain both bound to three specific sites along the collagen type I molecule, at the N terminus and at 100 and 220 nm from the N terminus. The N-terminal domain shortened the collagen fibril formation lag phase and tyrosine sulfation was required for this effect. The isolated leucine-rich repeat domain inhibited the fibril formation rate, and full-length fibromodulin showed a combination of these effects. The fibrils formed in the presence of fibromodulin or its fragments showed more organized structure. Fibromodulin and its tyrosine sulfate domain remained bound on the formed fiber. Taken together, this suggests a novel, regulatory function for tyrosine sulfation in collagen interaction and control of fibril formation. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Assessment of bone dysplasia by micro-CT and glycosaminoglycan levels in mouse models for mucopolysaccharidosis type I, IIIA, IVA, and VII

    PubMed Central

    Rowan, Daniel J.; Tomatsu, Shunji; Grubb, Jeffrey H.; Montaño, Adriana M.; Sly, William S.

    2012-01-01

    Summary Mucopolysaccharidoses (MPS) are a group of lysosomal storage diseases caused by mutations in lysosomal enzymes involved in degradation of glycosaminoglycans (GAGs). Patients with MPS grow poorly and become physically disabled due to systemic bone disease. While many of the major skeletal effects in mouse models for MPS have been described, no detailed analysis that compares GAGs levels and characteristics of bone by micro-CT has been done. The aims of this study were to assess severity of bone dysplasia among four MPS mouse models (MPS I, IIIA, IVA and VII), to determine the relationship between severity of bone dysplasia and serum keratan sulfate (KS) and heparan sulfate (HS) levels in those models, and to explore the mechanism of KS elevation in MPS I, IIIA, and VII mouse models. Clinically, MPS VII mice had the most severe bone pathology; however, MPS I and IVA mice also showed skeletal pathology. MPS I and VII mice showed severe bone dysplasia, higher bone mineral density, narrowed spinal canal, and shorter sclerotic bones by micro-CT and radiographs. Serum KS and HS levels were elevated in MPS I, IIIA, and VII mice. Severity of skeletal disease displayed by micro-CT, radiographs and histopathology correlated with the level of KS elevation. We showed that elevated HS levels in MPS mouse models could inhibit N-acetylgalactosamine-6-sulfate sulfatase enzyme. These studies suggest that KS could be released from chondrocytes affected by accumulation of other GAGs and that KS could be useful as a biomarker for severity of bone dysplasia in MPS disorders. PMID:22971960

  17. GLYCOSAMINOGLYCANS AND PROTEOGLYCANS IN PALMAR FASCIA OF PATIENTS WITH DUPUYTREN.

    PubMed

    Nascimento, Priscilla Carneiro Hirai; Kobayashi, Elsa Yoko; Lenzi, Luiz Guilherme de Saboya; Dos Santos, João Baptista Gomes; Nader, Helena Bonciani; Faloppa, Flávio

    2016-01-01

    : To evaluate and compare the behavior of glycosaminoglycans (GAGs) in Dupuytren disease (DD). : This is an experimental study with 23 patients diagnosed with DD. Tissue collected through fasciectomy with incision type Brunner or McCash were evaluated by electrophoresis for identification of GAGs. The quantification was carried out by immunofluorescence and dosage of proteins for different types of glycosaminoglycans. The results were expressed in percentage and statistically evaluated. : A significant increase was observed through eletrophoresis in GAGs, as compared to the control (p<0.05). Immunofluorescence of hyaluronic acid was reduced (23 times) when compared to the control (p<0.0001). : An increase of sulfated GAGs in Dupuytren's disease, mainly dermatan sulfate, was evident from our results, as well as a pronounced decrease of hyaluronic acid in the palmar aponeurosis from the same patients. Level of Evidence III, Case-Control Study.

  18. Cartilage elasticity resides in shape module decoran and aggrecan sumps of damping fluid: implications in osteoarthrosis

    PubMed Central

    Scott, John E; Stockwell, Robin A

    2006-01-01

    Cartilage ultrastructure is based on collagen fibrils tied together by proteoglycans (PGs). Interfibrillar orthogonal PG bridges (‘shape modules’) were located by electron histochemistry using Cupromeronic blue methodology. Their frequency and size, similar to those in tendon, cornea, etc., were compatible with biochemical estimates of tissue decoran (formerly decorin), the PG component of shape module bridges. Digestion by hyaluronanase and chondroitinase AC helped to identify aggrecan and decoran and exemplified the destruction of shape modular organization by glycan-splitting agents. The anionic glycosaminoglycan (AGAG) of decoran, dermochondan sulphate (DS, formerly dermatan sulphate), contains l-iduronate, an elastic sugar unit. Chondroitan, keratan (present in aggrecan) and hyaluronan are not similarly elastic but can participate in sliding-filament reversible deformability. Mechanical properties predicted for the interfibrillar bridges accord with anisotropic stress/strain responses of articular cartilage to compressive or tensile stresses. We propose that fluid from pericellular aggrecan-rich domains moves under pressure into the interterritorial fibrillar arrays against the elastic resistance of the shape modules, which return the fluid, post-compression, to its original position. Cartilage is tendon-like, with the addition of expansile aggrecan-rich reservoirs of aqueous shock absorber fluid. Rupture or loss of interfibrillar ties would allow expansile PG to force the collagenous matrix apart, imbibing water, increasing swelling and fissuring – characteristic manifestations of osteoarthrosis (OA), a joint disease of major economic importance. Decoran may be a primary target of the OA disease process. PMID:16581860

  19. Heparan Sulfates Support Pyramidal Cell Excitability, Synaptic Plasticity, and Context Discrimination.

    PubMed

    Minge, Daniel; Senkov, Oleg; Kaushik, Rahul; Herde, Michel K; Tikhobrazova, Olga; Wulff, Andreas B; Mironov, Andrey; van Kuppevelt, Toin H; Oosterhof, Arie; Kochlamazashvili, Gaga; Dityatev, Alexander; Henneberger, Christian

    2017-02-01

    Heparan sulfate (HS) proteoglycans represent a major component of the extracellular matrix and are critical for brain development. However, their function in the mature brain remains to be characterized. Here, acute enzymatic digestion of HS side chains was used to uncover how HSs support hippocampal function in vitro and in vivo. We found that long-term potentiation (LTP) of synaptic transmission at CA3-CA1 Schaffer collateral synapses was impaired after removal of highly sulfated HSs with heparinase 1. This reduction was associated with decreased Ca2+ influx during LTP induction, which was the consequence of a reduced excitability of CA1 pyramidal neurons. At the subcellular level, heparinase treatment resulted in reorganization of the distal axon initial segment, as detected by a reduction in ankyrin G expression. In vivo, digestion of HSs impaired context discrimination in a fear conditioning paradigm and oscillatory network activity in the low theta band after fear conditioning. Thus, HSs maintain neuronal excitability and, as a consequence, support synaptic plasticity and learning. © The Author 2017. Published by Oxford University Press.

  20. Congenital joint dislocations caused by carbohydrate sulfotransferase 3 deficiency in recessive Larsen syndrome and humero-spinal dysostosis.

    PubMed

    Hermanns, Pia; Unger, Sheila; Rossi, Antonio; Perez-Aytes, Antonio; Cortina, Hector; Bonafé, Luisa; Boccone, Loredana; Setzu, Valeria; Dutoit, Michel; Sangiorgi, Luca; Pecora, Fabio; Reicherter, Kerstin; Nishimura, Gen; Spranger, Jürgen; Zabel, Bernhard; Superti-Furga, Andrea

    2008-06-01

    Deficiency of carbohydrate sulfotransferase 3 (CHST3; also known as chondroitin-6-sulfotransferase) has been reported in a single kindred so far and in association with a phenotype of severe chondrodysplasia with progressive spinal involvement. We report eight CHST3 mutations in six unrelated individuals who presented at birth with congenital joint dislocations. These patients had been given a diagnosis of either Larsen syndrome (three individuals) or humero-spinal dysostosis (three individuals), and their clinical features included congenital dislocation of the knees, elbow joint dysplasia with subluxation and limited extension, hip dysplasia or dislocation, clubfoot, short stature, and kyphoscoliosis developing in late childhood. Analysis of chondroitin sulfate proteoglycans in dermal fibroblasts showed markedly decreased 6-O-sulfation but enhanced 4-O-sulfation, confirming functional impairment of CHST3 and distinguishing them from diastrophic dysplasia sulphate transporter (DTDST)-deficient cells. These observations provide a molecular basis for recessive Larsen syndrome and indicate that recessive Larsen syndrome, humero-spinal dysostosis, and spondyloepiphyseal dysplasia Omani type form a phenotypic spectrum.

  1. Inhibition of chondroitin sulfate glycosaminoglycans incorporation affected odontoblast differentiation in cultured embryonic mouse molars.

    PubMed

    Liu, Lipei; Chen, Weiting; Li, Lefeng; Xu, Fangfang; Jiang, Beizhan

    2017-12-01

    Chondroitin sulfate proteoglycan (CSPG) is an important component of extracellular matrix (ECM), it is composed of a core protein and one or more chondroitin sulfate glycosaminoglycan side chains (CS-GAGs). To investigate the roles of its CS-GAGs in dentinogenesis, the mouse mandibular first molar tooth germs at early bell stage were cultivated with or without β-xyloside. As expected, the CS-GAGs were inhibited on their incorporation to CSPGs by β-xyloside, accompanied by the change of morphology of the cultured tooth germs. The histological results and the transmission electron microscopy (TEM) investigation indicated that β-xyloside exhibited obvious inhibiting effects on odontoblasts differentiation compared with the control group. Meanwhile the results of immunohistochemistry, in situ hybridization and quantitative RT-PCR for type I collagen, dentin matrix acidic phosphoprotein 1 and dentin sialophosphoprotein, the products of differentiated odontoblasts, further proved that odontoblasts differentiation was inhibited. Collagen fibers detected in TEM decreased and arranged in disorder as well. Thus we conclude that the inhibition of CS-GAGs incorporation to CSPGs can affect odontoblast differentiation in cultured embryonic mouse molars.

  2. Decreasing the metastatic potential in cancers--targeting the heparan sulfate proteoglycans.

    PubMed

    Fjeldstad, K; Kolset, S O

    2005-09-01

    The heterogeneity of proteoglycans (PG)s contributes to their functional diversity. Many functions depend on their ability to bind and modulate the activity of components of the extracellular matrix (ECM). The ability of PGs to interact with other molecules, such as growth factors, is largely determined by the fine structure of the glycosaminoglycan (GAG) chains. Tumorigenesis is associated with changes in the PG synthesis. Heparan sulfate (HS) PGs are involved in several aspects of cancer biology including tumor progression, angiogenesis, and metastasis. PGs can have both tumor promoting and tumor suppressing activities depending on the protein core, the GAG attached, molecules they associate with, localization, the tumor subtype, stages, and degree of tumor differentiation. Perlecan is an angiogenic factor involved in tumor invasiveness. The C-terminal domain V of perlecan, named endorepellin, has however been shown to inhibit angiogenesis. Another angiogenic factor is endostatin, the COOH-terminal domain of the part-time PG collagen XVIII. Glypicans and syndecans may promote local cancer cell growth in some cancer tissues, but inhibit tissue invasion and metastasis in others. The GAG hyaluronan (HA) promotes cancer growth by providing a loose matrix for migrating tumor cells and mediates adhesion of cancer cells. HSPG degrading enzymes like heparanase, heparitinase, and other enzymes such as hyaluronidase and MMP are also important in tumor metastasis. Several different treatment strategies that target PGs have been developed. They have the potential to be effective in reducing tumor growth and inhibit the formation of metastases. PGs are also valuable tumor markers in several cancers.

  3. The Effects of Glucosamine Sulfate on Intervertebral Disc Annulus Fibrosus Cells in Vitro

    PubMed Central

    Sowa, Gwendolyn; Coelho, J. Paulo; Jacobs, Lloydine; Komperda, Kasey; Sherry, Nora; Vo, Nam; Preuss, Harry; Balk, Judith; Kang, Jame

    2014-01-01

    Background context Glucosamine has gained widespread use among patients, despite inconclusive efficacy data. Inconsistency in the clinical literature may be related to lack of understanding of the effects of glucosamine on the intervertebral disc, and therefore, improper patient selection. Purpose The goal of our study was to investigate the effects of glucosamine on intervertebral disc cells in vitro under the physiological conditions of inflammation and mechanical loading. Study Design Controlled in vitro laboratory setting Methods Intervertebral disc cells isolated from the rabbit annulus fibrosus were exposed to glucosamine sulfate in the presence and absence of interleukin-1beta and tensile strain. Outcome measures included gene expression, measurement of total glycosaminoglycans, new proteoglycan synthesis, prostaglandin E2 production, and matrix metalloproteinase activity. The study was funded by NIH/NCCAM and the authors have no conflicts of interest. Results Under conditions of inflammatory stimulation alone, glucosamine demonstrated a dose dependent effect in decreasing inflammatory and catabolic mediators and increasing anabolic genes. However, under conditions of mechanical stimulation, although inflammatory gene expression was decreased, PGE2 was not. In addition, MMP-3 gene expression was increased and aggrecan expression decreased, both of which would have a detrimental effect on matrix homeostasis. Consistent with this, measurement of total glycosaminoglycans and new proteoglycan synthesis demonstrated detrimental effects of glucosamine under all conditions tested. Conclusions These results may in part help to explain the conflicting reports of efficacy, as there is biological plausibility for a therapeutic effect under conditions of predominate inflammation, but not under conditions where mechanical loading is present or in which matrix synthesis is needed. PMID:24361347

  4. Differentiation of EL4 lymphoma cells by tumoral environment is associated with inappropriate expression of the large chondroitin sulfate proteoglycan PG-M and the tumor-associated antigen HTgp-175.

    PubMed

    Rottiers, P; Verfaillie, T; Contreras, R; Revets, H; Desmedt, M; Dooms, H; Fiers, W; Grooten, J

    1998-11-09

    Progression to malignancy of transformed cells involves complex genetic alterations and aberrant gene expression patterns. While aberrant gene expression is often caused by alterations in individual genes, the contribution of the tumoral environment to the triggering of this gene expression is less well established. The stable but heterogeneous expression in cultured EL4/13 cells of a novel tumor-associated antigen, designated as HTgp-175, was chosen for the investigation of gene expression during tumor formation. Homogeneously HTgp-175-negative EL4/13 cells, isolated by cell sorting or obtained by subcloning, acquired HTgp-175 expression as a result of tumor formation. The tumorigenicity of HTgp-175-negative vs. HTgp-175-positive EL4 variants was identical, indicating that induction but not selection accounted for the phenotypic switch from HTgp-175-negative to HTgp-175-positive. Although mutagenesis experiments showed that the protein was not essential for tumor establishment, tumor-derived cells showed increased malignancy, linking HTgp-175 expression with genetic changes accompanying tumor progression. This novel gene expression was not an isolated event, since it was accompanied by ectopic expression of the large chondroitin sulfate proteoglycan PG-M and of normal differentiation antigens. We conclude that signals derived from the tumoral microenvironment contribute significantly to the aberrant gene expression pattern of malignant cells, apparently by fortuitous activation of differentiation processes and cause expression of novel differentiation antigens as well as of inappropriate tumor-associated and ectopic antigens.

  5. Distorted secretory granule composition in mast cells with multiple protease deficiency.

    PubMed

    Grujic, Mirjana; Calounova, Gabriela; Eriksson, Inger; Feyerabend, Thorsten; Rodewald, Hans-Reimer; Tchougounova, Elena; Kjellén, Lena; Pejler, Gunnar

    2013-10-01

    Mast cells are characterized by an abundance of secretory granules densely packed with inflammatory mediators such as bioactive amines, cytokines, serglycin proteoglycans with negatively charged glycosaminoglycan side chains of either heparin or chondroitin sulfate type, and large amounts of positively charged proteases. Despite the large biological impact of mast cell granules and their contents on various pathologies, the mechanisms that regulate granule composition are incompletely understood. In this study, we hypothesized that granule composition is dependent on a dynamic electrostatic interrelationship between different granule compounds. As a tool to evaluate this possibility, we generated mice in which mast cells are multideficient in a panel of positively charged proteases: the chymase mouse mast cell protease-4, the tryptase mouse mast cell protease-6, and carboxypeptidase A3. Through a posttranslational effect, mast cells from these mice additionally lack mouse mast cell protease-5 protein. Mast cells from mice deficient in individual proteases showed normal morphology. In contrast, mast cells with combined protease deficiency displayed a profound distortion of granule integrity, as seen both by conventional morphological criteria and by transmission electron microscopy. An assessment of granule content revealed that the distorted granule integrity in multiprotease-deficient mast cells was associated with a profound reduction of highly negatively charged heparin, whereas no reduction in chondroitin sulfate storage was observed. Taken together with previous findings showing that the storage of basic proteases conversely is regulated by anionic proteoglycans, these data suggest that secretory granule composition in mast cells is dependent on a dynamic interrelationship between granule compounds of opposite electrical charge.

  6. Transforming growth factor β-induced expression of chondroitin sulfate proteoglycans is mediated through non-Smad signaling pathways.

    PubMed

    Jahan, Naima; Hannila, Sari S

    2015-01-01

    The expression of chondroitin sulfate proteoglycans (CSPGs) by reactive astrocytes is a major factor contributing to glial scarring and regenerative failure after spinal cord injury, but the molecular mechanisms underlying CSPG expression remain largely undefined. One contributing factor is transforming growth factor β (TGFβ), which is upregulated after injury and has been shown to induce expression of CSPGs in vitro. TGFβ typically mediates its effects through the Smad2/3 signaling pathway, and it has been suggested that this pathway is responsible for CSPG expression. However, there is evidence that TGFβ can also activate non-Smad signaling pathways. In this study, we report that TGFβ-induced expression of three different CSPGs--neurocan, brevican, and aggrecan--is mediated through non-Smad signaling pathways. We observed significant increases in TGFβ-induced expression of neurocan, brevican, and aggrecan following siRNA knockdown of Smad2 or Smad4, which indicates that Smad signaling is not required for the expression of these CSPGs. In addition, we show that neurocan, aggrecan, and brevican levels are significantly reduced when TGFβ is administered in the presence of either the PI3K inhibitor LY294002 or the mTOR inhibitor rapamycin, but not the MEK1/2 inhibitor U0126. This suggests that TGFβ mediates this effect through non-Smad-dependent activation of the PI3K-Akt-mTOR signaling pathway, and targeting this pathway may therefore be an effective means of reducing CSPG expression in the injured CNS. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Disturbed Laminar Blood Flow Vastly Augments Lipoprotein Retention in the Artery Wall: A Key Mechanism Distinguishing Susceptible From Resistant Sites.

    PubMed

    Steffensen, Lasse Bach; Mortensen, Martin Bødtker; Kjolby, Mads; Hagensen, Mette Kallestrup; Oxvig, Claus; Bentzon, Jacob Fog

    2015-09-01

    Atherosclerosis develops initially at branch points and in areas of high vessel curvature. Moreover, experiments in hypercholesterolemic mice have shown that the introduction of disturbed flow in straight, atherosclerosis-resistant arterial segments turns them highly atherosclerosis susceptible. Several biomechanical mechanisms have been proposed, but none has been demonstrated. In the present study, we examined whether a causal link exists between disturbed laminar flow and the ability of the arterial wall to retain lipoproteins. Lipoprotein retention was detected at natural predilection sites of the murine thoracic aorta 18 hours after infusion of fluorescently labeled low-density lipoprotein. To test for causality between blood flow and the ability of these areas to retain lipoproteins, we manipulated blood flow in the straight segment of the common carotid artery using a constrictive collar. Disturbed laminar flow did not affect low-density lipoprotein influx, but increased the ability of the artery wall to bind low-density lipoprotein. Concordantly, disturbed laminar flow led to differential expression of genes associated with phenotypic modulation of vascular smooth muscle cells, increased expression of proteoglycan core proteins associated with lipoprotein retention, and of enzymes responsible for chondroitin sulfate glycosaminoglycan synthesis and sulfation. Blood flow regulates genes associated with vascular smooth muscle cell phenotypic modulation, as well as the expression and post-translational modification of lipoprotein-binding proteoglycan core proteins, and the introduction of disturbed laminar flow vastly augments the ability of a previously resistant, straight arterial segment to retain lipoproteins. © 2015 American Heart Association, Inc.

  8. Localization of extracellular matrix components in developing mouse salivary glands by confocal microscopy

    NASA Technical Reports Server (NTRS)

    Hardman, P.; Spooner, B. S.

    1992-01-01

    The importance of the extracellular matrix (ECM) in epithelial-mesenchymal interactions in developing organisms is well established. Proteoglycans and interstitial collagens are required for the growth, morphogenesis, and differentiation of epithelial organs and the distribution of these molecules has been described. However, much less is known about other ECM macromolecules in developing epithelial organs. We used confocal microscopy to examine the distribution of laminin, heparan sulfate (BM-1) proteoglycan, fibronectin, and collagen types I, IV, and V, in mouse embryonic salivary glands. Organ rudiments were isolated from gestational day 13 mouse embryos and cultured for 24, 48, or 72 hours. Whole mounts were stained by indirect immunofluorescence and then examined using a Zeiss Laser Scan Microscope. We found that each ECM component examined had a distinct distribution and that the distribution of some molecules varied with culture time. Laminin was mainly restricted to the basement membrane. BM-1 proteoglycan was concentrated in the basement membrane and also formed a fine network throughout the mesenchyme. Type IV collagen was mainly located in the basement membrane of the epithelium, but it was also present throughout the mesenchyme. Type V collagen was distributed throughout the mesenchyme at 24 hours, but at 48 hours was principally located in the basement membrane. Type I collagen was distributed throughout the mesenchyme at all culture times, and accumulated in the clefts and particularly at the epithelial-mesenchymal interface as time in culture increased. Fibronectin was observed throughout the mesenchyme at all times.

  9. Atomic force microscopy of adsorbed proteoglycan mimetic nanoparticles: Toward new glycocalyx-mimetic model surfaces.

    PubMed

    Hedayati, Mohammadhasan; Kipper, Matt J

    2018-06-15

    Blood vessels present a dense, non-uniform, polysaccharide-rich layer, called the endothelial glycocalyx. The polysaccharides in the glycocalyx include polyanionic glycosaminoglycans (GAGs). This polysaccharide-rich surface has excellent and unique blood compatibility. We report new methods for preparing and characterizing dense GAG surfaces that can serve as models of the vascular endothelial glycocalyx. The GAG-rich surfaces are prepared by adsorbing heparin or chondroitin sulfate-containing polyelectrolyte complex nanoparticles (PCNs) to chitosan-hyaluronan polyelectrolyte multilayers (PEMs). The surfaces are characterized by PeakForce tapping atomic force microscopy, both in air and in aqueous pH 7.4 buffer, and by PeakForce quantitative nanomechanics (PF-QNM) mode with high spatial resolution. These new surfaces provide access to heparin-rich or chondroitin sulfate-rich coatings that mimic both composition and nanoscale structural features of the vascular endothelial glycocalyx. Copyright © 2018. Published by Elsevier Ltd.

  10. Mechanisms of Heparanase Inhibitors in Cancer Therapy

    PubMed Central

    Heyman, Benjamin; Yang, Yiping

    2016-01-01

    Heparanase is an endo-β-D-glucuronidase capable of cleaving heparan sulfate (HS) side chains contributing to break down of the extracellular matrix. Increased expression of heparanase has been found in numerous malignancies, and is associated with a poor prognosis. It has generated significant interest as a potential anti-neoplastic target because of the multiple roles it plays in tumor growth and metastasis. The pro-tumorigenic effects of heparanase are enhanced by the release of HS side chains, with subsequent increase in bioactive fragments and increased cytokine levels; both promoting tumor invasion, angiogenesis and metastasis. Preclinical experiments have shown heparanase inhibitors to substantially reduce tumor growth and metastasis leading to clinical trials with heparan sulfate mimetics. In this review we will examine heparanase’s role in tumor biology, its interaction with heparan surface proteoglycans, specifically syndecan-1; as well as the mechanism of action for heparanase inhibitors developed as anti-neoplastic therapeutics. PMID:27576132

  11. Roles of Heparan Sulfate Sulfation in Dentinogenesis*

    PubMed Central

    Hayano, Satoru; Kurosaka, Hiroshi; Yanagita, Takeshi; Kalus, Ina; Milz, Fabian; Ishihara, Yoshihito; Islam, Md. Nurul; Kawanabe, Noriaki; Saito, Masahiro; Kamioka, Hiroshi; Adachi, Taiji; Dierks, Thomas; Yamashiro, Takashi

    2012-01-01

    Cell surface heparan sulfate (HS) is an essential regulator of cell signaling and development. HS traps signaling molecules, like Wnt in the glycosaminoglycan side chains of HS proteoglycans (HSPGs), and regulates their functions. Endosulfatases Sulf1 and Sulf2 are secreted at the cell surface to selectively remove 6-O-sulfate groups from HSPGs, thereby modifying the affinity of cell surface HSPGs for its ligands. This study provides molecular evidence for the functional roles of HSPG sulfation and desulfation in dentinogenesis. We show that odontogenic cells are highly sulfated on the cell surface and become desulfated during their differentiation to odontoblasts, which produce tooth dentin. Sulf1/Sulf2 double null mutant mice exhibit a thin dentin matrix and short roots combined with reduced expression of dentin sialophosphoprotein (Dspp) mRNA, encoding a dentin-specific extracellular matrix precursor protein, whereas single Sulf mutants do not show such defective phenotypes. In odontoblast cell lines, Dspp mRNA expression is potentiated by the activation of the Wnt canonical signaling pathway. In addition, pharmacological interference with HS sulfation promotes Dspp mRNA expression through activation of Wnt signaling. On the contrary, the silencing of Sulf suppresses the Wnt signaling pathway and subsequently Dspp mRNA expression. We also show that Wnt10a protein binds to cell surface HSPGs in odontoblasts, and interference with HS sulfation decreases the binding affinity of Wnt10a for HSPGs, which facilitates the binding of Wnt10a to its receptor and potentiates the Wnt signaling pathway, thereby up-regulating Dspp mRNA expression. These results demonstrate that Sulf-mediated desulfation of cellular HSPGs is an important modification that is critical for the activation of the Wnt signaling in odontoblasts and for production of the dentin matrix. PMID:22351753

  12. A novel method to identify hub pathways of rheumatoid arthritis based on differential pathway networks.

    PubMed

    Wei, Shi-Tong; Sun, Yong-Hua; Zong, Shi-Hua

    2017-09-01

    The aim of the current study was to identify hub pathways of rheumatoid arthritis (RA) using a novel method based on differential pathway network (DPN) analysis. The present study proposed a DPN where protein‑protein interaction (PPI) network was integrated with pathway‑pathway interactions. Pathway data was obtained from background PPI network and the Reactome pathway database. Subsequently, pathway interactions were extracted from the pathway data by building randomized gene‑gene interactions and a weight value was assigned to each pathway interaction using Spearman correlation coefficient (SCC) to identify differential pathway interactions. Differential pathway interactions were visualized using Cytoscape to construct a DPN. Topological analysis was conducted to identify hub pathways that possessed the top 5% degree distribution of DPN. Modules of DPN were mined according to ClusterONE. A total of 855 pathways were selected to build pathway interactions. By filtrating pathway interactions of weight values >0.7, a DPN with 312 nodes and 791 edges was obtained. Topological degree analysis revealed 15 hub pathways, such as heparan sulfate/heparin‑glycosaminoglycan (HS‑GAG) degradation, HS‑GAG metabolism and keratan sulfate degradation for RA based on DPN. Furthermore, hub pathways were also important in modules, which validated the significance of hub pathways. In conclusion, the proposed method is a computationally efficient way to identify hub pathways of RA, which identified 15 hub pathways that may be potential biomarkers and provide insight to future investigation and treatment of RA.

  13. Immunohistochemical Analysis Using Antipodocalyxin Monoclonal Antibody PcMab-47 Demonstrates Podocalyxin Expression in Oral Squamous Cell Carcinomas.

    PubMed

    Itai, Shunsuke; Yamada, Shinji; Kaneko, Mika K; Harada, Hiroyuki; Kato, Yukinari

    2017-10-01

    Podocalyxin is a CD34-related type I transmembrane protein that is highly glycosylated with N-glycan, O-glycan, and keratan sulfate. Podocalyxin was originally found in the podocytes of rat kidney and is reportedly expressed in many types of tumors, including brain tumors, colorectal cancers, and breast cancers. Overexpression of podocalyxin is an independent predictor of progression, metastasis, and poor outcome. We recently immunized mice with recombinant human podocalyxin, which was produced using LN229 glioblastoma cells, and produced a novel antipodocalyxin monoclonal antibody (mAb), PcMab-47, which reacts with endogenous podocalyxin-expressing cancer cell lines and normal cell lines independent of glycosylation in Western blot, flow cytometry, and immunohistochemical analyses. In this study, we performed immunohistochemical analysis against oral cancers using PcMab-47. PcMab-47-stained oral squamous cell carcinoma cells in a cytoplasmic pattern and detected 26/38 (68.4%) of oral squamous cell carcinoma cells on tissue microarrays. These results indicate that PcMab-47 is useful in detecting podocalyxin of oral cancers for immunohistochemical analysis.

  14. Symptom and structure modification in osteoarthritis with pharmaceutical-grade chondroitin sulfate: what's the evidence?

    PubMed

    Hochberg, M; Chevalier, X; Henrotin, Y; Hunter, D J; Uebelhart, D

    2013-03-01

    Osteoarthritis is a chronic disease characterized by irreversible damage to joint structures, including loss of articular cartilage, osteophyte formation, alterations in the subchondral bone and synovial inflammation. It has been shown that chondroitin sulfate interferes with the progression of structural changes in joint tissues and is used in the management of patients with osteoarthritis. This review summarizes data from relevant reports describing the mechanisms of action of chondroitin sulfate that may explain the beneficial effects of the drug and examines the evidence for clinical efficacy of oral chondroitin sulfate in osteoarthritis. Data included in the review were derived from a literature search in PubMed. Literature searches were performed in PubMed using the search terms 'chondroitin sulfate', 'pharmaceutical-grade', 'osteoarthritis', 'randomized clinical trials', 'humans'. The MEDLINE database was searched from January 1996 through August 2012 for all randomized controlled trials, meta-analyses, systematic reviews, and review articles of chondroitin sulfate in osteoarthritis. Chondroitin sulfate exerts in vitro a beneficial effect on the metabolism of different cell lines: chondrocytes, synoviocytes and cells from subchondral bone, all involved in osteoarthritis. It increases type II collagen and proteoglycan synthesis in human articular chondrocytes and is able to reduce the production of some pro-inflammatory factors and proteases, to reduce the cellular death process, and improve the anabolic/catabolic balance of the extracellular cartilage matrix (ECM). Clinical trials have reported a beneficial effect of chondroitin sulfate on pain and function. The structure-modifying effects of chondroitin sulfate have been reported and analyzed in recent meta-analyses. The results in knee osteoarthritis demonstrate a small but significant reduction in the rate of decline in joint space width. Because chondroitin sulfate quality of several nutraceuticals has been found to be poor, it is recommended that pharmaceutical-grade chondroitin sulfate is used rather than food supplements in the treatment of OA. Chondroitin sulfate is recommended by several guidelines from international societies in the management of knee and hip OA. Furthermore, its safety profile is favorable when compared with many other therapies used in OA. Chondroitin sulfate is an effective and safe treatment option for patients with osteoarthritis.

  15. The heparin/heparan sulfate sequence that interacts with cyclophilin B contains a 3-O-sulfated N-unsubstituted glucosamine residue.

    PubMed

    Vanpouille, Christophe; Deligny, Audrey; Delehedde, Maryse; Denys, Agnès; Melchior, Aurélie; Liénard, Xavier; Lyon, Malcolm; Mazurier, Joël; Fernig, David G; Allain, Fabrice

    2007-08-17

    Many of the biological functions of heparan sulfate (HS) proteoglycans can be attributed to specialized structures within HS moieties, which are thought to modulate binding and function of various effector proteins. Cyclophilin B (CyPB), which was initially identified as a cyclosporin A-binding protein, triggers migration and integrin-mediated adhesion of peripheral blood T lymphocytes by a mechanism dependent on interaction with cell surface HS. Here we determined the structural features of HS that are responsible for the specific binding of CyPB. In addition to the involvement of 2-O,6-O, and N-sulfate groups, we also demonstrated that binding of CyPB was dependent on the presence of N-unsubstituted glucosamine residues (GlcNH2), which have been reported to be precursors for sulfation by 3-O-sulfotransferases-3 (3-OST-3). Interestingly, 3-OST-3B isoform was found to be the main 3-OST isoenzyme expressed in peripheral blood T lymphocytes and Jurkat T cells. Moreover, down-regulation of the expression of 3-OST-3 by RNA interference potently reduced CyPB binding and consequent activation of p44/42 mitogen-activated protein kinases. Altogether, our results strongly support the hypothesis that 3-O-sulfation of GlcNH2 residues could be a key modification that provides specialized HS structures for CyPB binding to responsive cells. Given that 3-O-sulfation of GlcNH2-containing HS by 3-OST-3 also provides binding sites for glycoprotein gD of herpes simplex virus type I, these findings suggest an intriguing structural linkage between the HS sequences involved in CyPB binding and viral infection.

  16. Chondroitin Sulfate-E Binds to Both Osteoactivin and Integrin αVβ3 and Inhibits Osteoclast Differentiation.

    PubMed

    Miyazaki, Tatsuya; Miyauchi, Satoshi; Anada, Takahisa; Tawada, Akira; Suzuki, Osamu

    2015-10-01

    Integrins and their ligands have been suggested to be associated with osteoclast-mediated bone resorption. The present study was designed to investigate whether chondroitin sulfate E (CS-E), which is one of the sulfated glycosaminoglycans (GAGs), is involved in osteoactivin (OA) activity, and osteoclast differentiation. The binding affinity of sulfated GAGs to integrin and its ligand was measured using biotin-labeled CS-E, and the osteoclast differentiation was evaluated by tartrate-resistant acid phosphatase staining and a pit formation assay. CS-E as well as CS-B, synthetic chondroitin polysulfate, and heparin inhibited osteoclast differentiation of bone marrow-derived macrophages. Pre-coating of OA to synthetic calcium phosphate-coated plates enhanced the osteoclastic differentiation of RAW264 cells, and addition of a neutralizing antibody to OA inhibited its differentiation. CS-E bound not only to OA, fibronectin, and vitronectin, but also to its receptor integrin αVβ3, and inhibited the direct binding of OA to integrin αVβ3. Furthermore, CS-E blocked the binding of OA to cells and inhibited OA-induced osteoclastic differentiation. On the other hand, heparinase treatment of RAW264 cells inhibited osteoclastic differentiation. Since binding of OA to the cells was inhibited by the presence of heparan sulfate or heparinase treatment of cells, heparan sulfate proteoglycan (HSPG) was also considered to be an OA receptor. Taken together, the present results suggest that CS-E is capable of inhibiting OA-induced osteoclast differentiation by blocking the interaction of OA to integrin αVβ3 and HSPG. © 2015 Wiley Periodicals, Inc.

  17. Chondroitin 6-O-sulfate ameliorates experimental autoimmune encephalomyelitis.

    PubMed

    Miyamoto, Katsuichi; Tanaka, Noriko; Moriguchi, Kota; Ueno, Rino; Kadomatsu, Kenji; Kitagawa, Hiroshi; Kusunoki, Susumu

    2014-05-01

    Chondroitin sulfate proteoglycans (CSPGs) are the main component of the extracellular matrix in the central nervous system (CNS) and influence neuroplasticity. Although CSPG is considered an inhibitory factor for nerve repair in spinal cord injury, it is unclear whether CSPG influences the pathogenetic mechanisms of neuroimmunological diseases. We induced experimental autoimmune encephalomyelitis (EAE) in chondroitin 6-O-sulfate transferase 1-deficient (C6st1(-/-)) mice. C6ST1 is the enzyme that transfers sulfate residues to position 6 of N-acetylgalactosamine in the sugar chain of CSPG. The phenotypes of EAE in C6st1(-/-) mice were more severe than those in wild-type (WT) mice were. In adoptive-transfer EAE, in which antigen-reactive T cells from WT mice were transferred to C6st1(-/-) and WT mice, phenotypes were significantly more severe in C6st1(-/-) than in WT mice. The recall response of antigen-reactive T cells was not significantly different among the groups. Furthermore, the number of pathogenic T cells within the CNS was also not considerably different. When EAE was induced in C6ST1 transgenic mice with C6ST1 overexpression, the mice showed considerably milder symptoms compared with those in WT mice. In conclusion, the presence of sulfate at position 6 of N-acetylgalactosamine of CSPG may influence the effecter phase of EAE to prevent the progression of pathogenesis. Thus, modification of the carbohydrate residue of CSPG may be a novel therapeutic strategy for neuroimmunological diseases such as multiple sclerosis.

  18. Proportion of collagen type II in the extracellular matrix promotes the differentiation of human adipose-derived mesenchymal stem cells into nucleus pulposus cells.

    PubMed

    Tao, Yiqing; Zhou, Xiaopeng; Liu, Dongyu; Li, Hao; Liang, Chengzhen; Li, Fangcai; Chen, Qixin

    2016-01-01

    During degeneration process, the catabolism of collagen type II and anabolism of collagen type I in nucleus pulposus (NP) may influence the bioactivity of transplanted cells. Human adipose-derived mesenchymal stem cells (hADMSCs) were cultured as a micromass or in a series of gradual proportion hydrogels of a mix of collagen types I and II. Cell proliferation and cytotoxicity were detected using CCK-8 and LDH assays respectively. The expression of differentiation-related genes and proteins, including SOX9, aggrecan, collagen type I, and collagen type II, was examined using RT-qPCR and Western blotting. Novel phenotypic genes were also detected by RT-qPCR and western blotting. Alcian blue and dimethylmethylene blue assays were used to investigate sulfate proteoglycan expression, and PI3K/AKT, MAPK/ERK, and Smad signaling pathways were examined by Western blotting. The results showed collagen hydrogels have good biocompatibility, and cell proliferation increased after collagen type II treatment. Expressions of SOX9, aggrecan, and collagen type II were increased in a collagen type II dependent manner. Sulfate proteoglycan synthesis increased in proportion to collagen type II concentration. Only hADMSCs highly expressed NP cell marker KRT19 in collagen type II culture. Additionally, phosphorylated Smad3, which is associated with phosphorylated ERK, was increased after collagen type II-stimulation. The concentration and type of collagen affect hADMSC differentiation into NP cells. Collagen type II significantly ameliorates hADMSC differentiation into NP cells and promotes extracellular matrix synthesis. Therefore, anabolism of collagen type I and catabolism of type II may attenuate the differentiation and biosynthesis of transplanted stem cells. © 2016 International Union of Biochemistry and Molecular Biology.

  19. Heparan Sulfate Proteoglycans as Drivers of Neural Progenitors Derived From Human Mesenchymal Stem Cells.

    PubMed

    Okolicsanyi, Rachel K; Oikari, Lotta E; Yu, Chieh; Griffiths, Lyn R; Haupt, Larisa M

    2018-01-01

    Background: Due to their relative ease of isolation and their high ex vivo and in vitro expansive potential, human mesenchymal stem cells (hMSCs) are an attractive candidate for therapeutic applications in the treatment of brain injury and neurological diseases. Heparan sulfate proteoglycans (HSPGs) are a family of ubiquitous proteins involved in a number of vital cellular processes including proliferation and stem cell lineage differentiation. Methods: Following the determination that hMSCs maintain neural potential throughout extended in vitro expansion, we examined the role of HSPGs in mediating the neural potential of hMSCs. hMSCs cultured in basal conditions (undifferentiated monolayer cultures) were found to co-express neural markers and HSPGs throughout expansion with modulation of the in vitro niche through the addition of exogenous HS influencing cellular HSPG and neural marker expression. Results: Conversion of hMSCs into hMSC Induced Neurospheres (hMSC IN) identified distinctly localized HSPG staining within the spheres along with altered gene expression of HSPG core protein and biosynthetic enzymes when compared to undifferentiated hMSCs. Conclusion: Comparison of markers of pluripotency, neural self-renewal and neural lineage specification between hMSC IN, hMSC and human neural stem cell (hNSC H9) cultures suggest that in vitro generated hMSC IN may represent an intermediary neurogenic cell type, similar to a common neural progenitor cell. In addition, this data demonstrates HSPGs and their biosynthesis machinery, are associated with hMSC IN formation. The identification of specific HSPGs driving hMSC lineage-specification will likely provide new markers to allow better use of hMSCs in therapeutic applications and improve our understanding of human neurogenesis.

  20. Heparan Sulfate in Perlecan Promotes Mouse Atherosclerosis: Roles in Lipid Permeability, Lipid Retention, and Smooth Muscle Cell Proliferation

    PubMed Central

    Tran-Lundmark, Karin; Tran, Phan-Kiet; Paulsson-Berne, Gabrielle; Fridén, Vincent; Soininen, Raija; Tryggvason, Karl; Wight, Thomas N; Kinsella, Michael G; Borén, Jan; Hedin, Ulf

    2009-01-01

    Heparan sulfate (HS) has been proposed to be anti-atherogenic through inhibition of lipoprotein retention, inflammation, and smooth muscle cell proliferation. Perlecan is the predominant HS proteoglycan in the artery wall. Here, we investigated the role of perlecan HS chains using apoE null (ApoE0) mice that were cross-bred with mice expressing HS-deficient perlecan (Hspg2Δ3/Δ3). Morphometry of cross-sections from aortic roots and en face preparations of whole aortas revealed a significant decrease in lesion formation in ApoE0/Hspg2Δ3/Δ3 mice at both 15 and 33 weeks. In vitro, binding of labeled mouse triglyceride-rich lipoproteins and human LDL to total extracellular matrix, as well as to purified proteoglycans, prepared from ApoE0/Hspg2Δ3/Δ3 smooth muscle cells was reduced. In vivo, at 20 min influx of human 125I-LDL or mouse triglyceride-rich lipoproteins into the aortic wall was increased in ApoE0/Hspg2Δ3/Δ3 mice compared to ApoE0 mice. However, at 72 hours accumulation of 125I-LDL was similar in ApoE0/Hspg2Δ3/Δ3 and ApoE0 mice. Immunohistochemistry of lesions from ApoE0/Hspg2Δ3/Δ3 mice showed decreased staining for apoB and increased smooth muscle α-actin content, whereas accumulation of CD68-positive inflammatory cells was unchanged. We conclude that the perlecan HS chains are pro-atherogenic in mice, possibly through increased lipoprotein retention, altered vascular permeability, or other mechanisms. The ability of HS to inhibit smooth muscle cell growth may also influence development as well as instability of lesions. PMID:18596265

  1. Regulation of cytokine signaling by B cell antigen receptor and CD40-controlled expression of heparan sulfate proteoglycans.

    PubMed

    van der Voort, R; Keehnen, R M; Beuling, E A; Spaargaren, M; Pals, S T

    2000-10-16

    Recently, biochemical, cell biological, and genetic studies have converged to reveal that integral membrane heparan sulfate proteoglycans (HSPGs) are critical regulators of growth and differentiation of epithelial and connective tissues. As a large number of cytokines involved in lymphoid tissue homeostasis or inflammation contain potential HS-binding domains, HSPGs presumably also play important roles in the regulation of the immune response. In this report, we explored the expression, regulation, and function of HSPGs on B lymphocytes. We demonstrate that activation of the B cell antigen receptor (BCR) and/or CD40 induces a strong transient expression of HSPGs on human tonsillar B cells. By means of these HSPGs, the activated B cells can bind hepatocyte growth factor (HGF), a cytokine that regulates integrin-mediated B cell adhesion and migration. This interaction with HGF is highly selective since the HSPGs did not bind the chemokine stromal cell-derived factor (SDF)-1 alpha, even though the affinities of HGF and SDF-1alpha for heparin are similar. On the activated B cells, we observed induction of a specific HSPG isoform of CD44 (CD44-HS), but not of other HSPGs such as syndecans or glypican-1. Interestingly, the expression of CD44-HS on B cells strongly promotes HGF-induced signaling, resulting in an HS-dependent enhanced phosphorylation of Met, the receptor tyrosine kinase for HGF, as well as downstream signaling molecules including Grb2-associated binder 1 (Gab1) and Akt/protein kinase B (PKB). Our results demonstrate that the BCR and CD40 control the expression of HSPGs, specifically CD44-HS. These HSPGs act as functional coreceptors that selectively promote cytokine signaling in B cells, suggesting a dynamic role for HSPGs in antigen-specific B cell differentiation.

  2. RNA interference targeting carbohydrate sulfotransferase 3 diminishes macrophage accumulation, inhibits MMP-9 expression and promotes lung recovery in murine pulmonary emphysema.

    PubMed

    Kai, Yoshiro; Tomoda, Koichi; Yoneyama, Hiroyuki; Yoshikawa, Masanori; Kimura, Hiroshi

    2015-12-09

    Chondroitin sulfate proteoglycans are an important mediators in inflammation and leukocyte trafficking. However, their roles in pulmonary emphysema have not been explored. In a murine model of elastase-induced pulmonary emphysema, we found increased carbohydrate sulfotransferase 3 (CHST3), a specific enzyme that synthesizes chondroitin 6-sulfate proteoglycan (C6SPG). To elucidate the role of C6SPG, we investigated the effect of small interfering RNA (siRNA) targeting CHST3 that inhibits C6SPG-synthesis on the pathogenesis of pulmonary emphysema. Mice were intraperitoneally injected with CHST3 siRNA or negative control siRNA on day0 and 7 after intratracheal instillation of elastase. Histology, respiratory function, glycosaminoglycans (GAGs) content, bronchoalveolar lavage (BAL), elastin staining and gene expressions of tumor necrosis factor (TNF)-α and matrix metalloproteinase (MMP)-9 mRNA were evaluated on day7 and/or day21. CHST3 mRNA increased at day 7 and decreased thereafter in lung. CHST3 siRNA successfully inhibited the expression of CHST3 mRNA throughout the study and this was associated with significant reduction of GAGs and C6SPG. Airway destruction and respiratory function were improved by the treatment with CHST3 siRNA. CHST3 siRNA reduced the number of macrophages both in BAL and lung parenchyma and also suppressed the increased expressions of TNF-α and MMP-9 mRNA. Futhermore, CHST3 siRNA improved the reduction of the elastin in the alveolar walls. CHST3 siRNA diminishes accumulation of excessive macrophages and the mediators, leading to accelerate the functional recovery from airway damage by repair of the elastin network associated with pulmonary emphysema.

  3. Proinflammatory cytokine activities, matrix metalloproteinase-3 activity, and sulfated glycosaminoglycan content in synovial fluid of dogs with naturally acquired cranial cruciate ligament rupture.

    PubMed

    Fujita, Yukihiro; Hara, Yasushi; Nezu, Yoshinori; Schulz, Kurt S; Tagawa, Masahiro

    2006-06-01

    To measure and compare activities of interleukin-1beta (IL-1beta), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and matrix metalloproteinase-3 (MMP-3); as well as sulfated glycosaminoglycan (S-GAG) content in synovial fluid from dogs with cranial cruciate ligament rupture (CCLR) and dogs with clinically normal stifles. To determine whether correlations exist between demographic and disease-related variables and these synovial markers. Prospective clinical study. Dogs with CCLR (n=23) and Beagles with normal stifle joints (n=21). Synovial fluid activities of proinflammatory cytokines (IL-1beta, IL-6, and TNF-alpha) were determined by bioassay. MMP-3 activity was measured using fluorogenic substrate. S-GAG contents were determined by dimethylmethylene blue dye-binding assay. Mann-Whitney U-test was used to compare results from CCLR joints with normal controls. Spearman's rank correlation test was used to evaluate associations between demographic and disease-related markers and synovial markers. Mean values for synovial markers were significantly higher in CCLR joints compared with controls. IL-1beta and MMP-3 were positively correlated with lameness duration. Activities of proinflammatory cytokines, MMP-3 activity and S-GAG contents were significantly elevated in synovial fluid from canine stifle joints with naturally acquired CCLR. These results indicate that there is joint inflammation and increased release of GAGs into synovial fluid, suggesting that these inflammatory changes are associated with depletion of proteoglycan from articular cartilage. Medical and surgical treatments designed to decrease joint inflammation and breakdown of proteoglycans may be of value in the management of CCLR in the dog.

  4. NG2/CSPG4 and progranulin in the posttraumatic glial scar.

    PubMed

    Schäfer, Michael K E; Tegeder, Irmgard

    2018-08-01

    Traumatic injury of the central nervous system is one of the leading causes of death and disability in young adults. Failure of regeneration is caused by autonomous neuronal obstacles and by formation of the glial scar, which is essential to seal the injury but also constitutes a barrier for regrowing axons. The scar center is highly inflammatory and populated by NG2+ glia, whereas astrocytes form the sealing border and trap regrowing axons, suggesting that the non-permissive environment of activated astrocytes and extracellular matrix components is one of the reasons for the regenerative failure. Particularly, secreted chondroitin-sulfate proteoglycans, CSPGs, of the lectican family hinder axonal regrowth. In contrast, the transmembrane CSPG, NG2/CSPG4, appears to be functionally closer related to axon growth permissive heparan sulfate proteoglycans, HSPGs, and synaptic adhesion molecules, which all regulate synaptic signaling and plasticity upon alpha-secretase mediated shedding. Consequently, knockout of NG2/CSPG4 aggravates tissue loss, inflammation and neurologic deficits after brain injury, a phenotype partly mimicked by deletion of HSPG-binding proteins such as the HSPG2/perlecan-interacting protein, progranulin that is also a functional ligand of Notch and Eph2a. Indeed, structural features or progranulin's targets and NG2 may point to direct reciprocal regulations that may act in concert to overcome injury-evoked inflammation and neuronal dystrophy. This review provides an overview of the pathophysiology of the glial scar after brain injury, with a specific focus on NG2/CSPG4, its functions before and after shedding and putative reciprocal influences with the glycoprotein progranulin. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Heparan sulfate in perlecan promotes mouse atherosclerosis: roles in lipid permeability, lipid retention, and smooth muscle cell proliferation.

    PubMed

    Tran-Lundmark, Karin; Tran, Phan-Kiet; Paulsson-Berne, Gabrielle; Fridén, Vincent; Soininen, Raija; Tryggvason, Karl; Wight, Thomas N; Kinsella, Michael G; Borén, Jan; Hedin, Ulf

    2008-07-03

    Heparan sulfate (HS) has been proposed to be antiatherogenic through inhibition of lipoprotein retention, inflammation, and smooth muscle cell proliferation. Perlecan is the predominant HS proteoglycan in the artery wall. Here, we investigated the role of perlecan HS chains using apoE null (ApoE0) mice that were cross-bred with mice expressing HS-deficient perlecan (Hspg2(Delta3/Delta3)). Morphometry of cross-sections from aortic roots and en face preparations of whole aortas revealed a significant decrease in lesion formation in ApoE0/Hspg2(Delta3/Delta3) mice at both 15 and 33 weeks. In vitro, binding of labeled mouse triglyceride-rich lipoproteins and human LDL to total extracellular matrix, as well as to purified proteoglycans, prepared from ApoE0/Hspg2(Delta3/Delta3) smooth muscle cells was reduced. In vivo, at 20 minutes influx of human (125)I-LDL or mouse triglyceride-rich lipoproteins into the aortic wall was increased in ApoE0/Hspg2(Delta3/Delta3) mice compared to ApoE0 mice. However, at 72 hours accumulation of (125)I-LDL was similar in ApoE0/Hspg2(Delta3/Delta3) and ApoE0 mice. Immunohistochemistry of lesions from ApoE0/Hspg2(Delta3/Delta3) mice showed decreased staining for apoB and increased smooth muscle alpha-actin content, whereas accumulation of CD68-positive inflammatory cells was unchanged. We conclude that the perlecan HS chains are proatherogenic in mice, possibly through increased lipoprotein retention, altered vascular permeability, or other mechanisms. The ability of HS to inhibit smooth muscle cell growth may also influence development as well as instability of lesions.

  6. Human Single-Chain Fv Immunoconjugates Targeted to a Melanoma-Associated Chondroitin Sulfate Proteoglycan Mediate Specific Lysis of Human Melanoma Cells by Natural Killer Cells and Complement

    NASA Astrophysics Data System (ADS)

    Wang, Baiyang; Chen, Yi-Bin; Ayalon, Oran; Bender, Jeffrey; Garen, Alan

    1999-02-01

    Two antimelanoma immunoconjugates containing a human single-chain Fv (scFv) targeting domain conjugated to the Fc effector domain of human IgG1 were synthesized as secreted two-chain molecules in Chinese hamster ovary and Drosophila S2 cells, and purified by affinity chromatography on protein A. The scFv targeting domains originally were isolated as melanoma-specific clones from a scFv fusion-phage library, derived from the antibody repertoire of a vaccinated melanoma patient. The purified immunoconjugates showed similar binding specificity as did the fusion-phage clones. Binding occurred to human melanoma cells but not to human melanocytes or to several other types of normal cells and tumor cells. A 250-kDa melanoma protein was immunoprecipitated by the immunoconjugates and analyzed by mass spectrometry, using two independent procedures. A screen of protein sequence databases showed an exact match of several peptide masses between the immunoprecipitated protein and the core protein of a chondroitin sulfate proteoglycan, which is expressed on the surface of most human melanoma cells. The Fc effector domain of the immunoconjugates binds natural killer (NK) cells and also the C1q protein that initiates the complement cascade; both NK cells and complement can activate powerful cytolytic responses against the targeted tumor cells. An in vitro cytolysis assay was used to test for an immunoconjugate-dependent specific cytolytic response against cultured human melanoma cells by NK cells and complement. The melanoma cells, but not the human fibroblast cells used as the control, were efficiently lysed by both NK cells and complement in the presence of the immunoconjugates. The in vitro results suggest that the immunoconjugates also could activate a specific cytolytic immune response against melanoma tumors in vivo.

  7. Anti-chondroitin sulfate proteoglycan 4-specific antibodies modify the effects of vemurafenib on melanoma cells differentially in normoxia and hypoxia

    PubMed Central

    PUCCIARELLI, DANIELA; LENGGER, NINA; TAKACOVA, MARTINA; CSADEROVA, LUCIA; BARTOSOVA, MARIA; BREITENEDER, HEIMO; PASTOREKOVA, SILVIA; HAFNER, CHRISTINE

    2015-01-01

    Chondroitin sulfate proteoglycan 4 (CSPG4), a highly immunogenic melanoma tumor antigen, is a potential target for antibody-based immunotherapy. The mechanism by which CSPG4 affects melanoma progression is only partly understood, in particular the involvement of other receptor tyrosine kinases and the tumor microenvironment. We have previously reported on a mimotope-based vaccine against CSPG4 in a human melanoma xenograft model that resulted in reduction of tumor growth. Herein we describe the influence of hypoxia on the response to polyclonal anti-CSPG4-antibodies induced by this vaccine in combination with the BRAF inhibitor vemurafenib to enhance therapeutic efficacy by simultaneously targeting multiple signaling pathways. Melanoma cells were treated with polyclonal anti-CSPG4-antibodies and vemurafenib. Proliferation, migration and invasion were evaluated in a real-time setting in the impedance-based x-CELLigence® system. Western blotting and quantitative PCR arrays were used to determine protein and mRNA expression of hypoxia inducible factor 1α (HIF1α), carbonic anhydrase IX (CAIX) and signaling pathway proteins. A melanoma xenograft model was used to detect HIF1α and CAIX expression in vivo. Hypoxia enhanced the antiproliferative response to vemurafenib. The migration and invasion capacities of vemurafenib-treated melanoma cells were increased, in spite of vemurafenib-decreased expression of HIF1α and CAIX. Polyclonal anti-CSPG4-antibodies reduced the Transwell migration of vemurafenib-treated, BRAF V600E-mutant and CSPG4-expressing melanoma cells in hypoxia. This was associated with the downregulation of phosphorylated AKT, a kinase contributing to tumor cell migration. Our results highlight CSPG4 as a potential target for modulating treatment resistance to vemurafenib induced by the hypoxic microenvironment. PMID:25997619

  8. Anti-chondroitin sulfate proteoglycan 4-specific antibodies modify the effects of vemurafenib on melanoma cells differentially in normoxia and hypoxia.

    PubMed

    Pucciarelli, Daniela; Lengger, Nina; Takacova, Martina; Csaderova, Lucia; Bartosova, Maria; Breiteneder, Heimo; Pastorekova, Silvia; Hafner, Christine

    2015-07-01

    Chondroitin sulfate proteoglycan 4 (CSPG4), a highly immunogenic melanoma tumor antigen, is a potential target for antibody-based immunotherapy. The mechanism by which CSPG4 affects melanoma progression is only partly understood, in particular the involvement of other receptor tyrosine kinases and the tumor microenvironment. We have previously reported on a mimotope-based vaccine against CSPG4 in a human melanoma xenograft model that resulted in reduction of tumor growth. Herein we describe the influence of hypoxia on the response to polyclonal anti-CSPG4-antibodies induced by this vaccine in combination with the BRAF inhibitor vemurafenib to enhance therapeutic efficacy by simultaneously targeting multiple signaling pathways. Melanoma cells were treated with polyclonal anti-CSPG4-antibodies and vemurafenib. Proliferation, migration and invasion were evaluated in a real-time setting in the impedance-based x-CELLigence® system. Western blotting and quantitative PCR arrays were used to determine protein and mRNA expression of hypoxia inducible factor 1α (HIF1α), carbonic anhydrase IX (CAIX) and signaling pathway proteins. A melanoma xenograft model was used to detect HIF1α and CAIX expression in vivo. Hypoxia enhanced the antiproliferative response to vemurafenib. The migration and invasion capacities of vemurafenib-treated melanoma cells were increased, in spite of vemurafenib-decreased expression of HIF1α and CAIX. Polyclonal anti-CSPG4-antibodies reduced the Transwell migration of vemurafenib-treated, BRAF V600E-mutant and CSPG4-expressing melanoma cells in hypoxia. This was associated with the downregulation of phosphorylated AKT, a kinase contributing to tumor cell migration. Our results highlight CSPG4 as a potential target for modulating treatment resistance to vemurafenib induced by the hypoxic microenvironment.

  9. Deposition of tropoelastin into the extracellular matrix requires a competent elastic fiber scaffold but not live cells.

    PubMed

    Kozel, Beth A; Ciliberto, Christopher H; Mecham, Robert P

    2004-04-01

    The initial steps of elastic fiber assembly were investigated using an in vitro assembly model in which purified recombinant tropoelastin (rbTE) was added to cultures of live or dead cells. The ability of tropoelastin to associate with preexisting elastic fibers or microfibrils in the extracellular matrix was then assessed by immunofluorescence microscopy using species-specific tropoelastin antibodies. Results show that rbTE can associate with elastic fiber components in the absence of live cells through a process that does not depend on crosslink formation. Time course studies show a transformation of the deposited protein from an initial globular appearance early in culture to a more fibrous structure as the matrix matures. Deposition required the C-terminal region of tropoelastin and correlated with the presence of preexisting elastic fibers or microfibrils. Association of exogenously added tropoelastin to the cellular extracellular matrix was inhibited by the addition of heparan sulfate but not chondroitin sulfate sugars. Together, these results suggest that the matrix elaborated by the cell is sufficient for the initial deposition of tropoelastin in the extracellular space and that elastin assembly may be influenced by the composition of sulfated proteoglycans in the matrix.

  10. Medical Gains of Chondroitin Sulfate Upon Fucosylation.

    PubMed

    Pomin, Vitor H

    2015-01-01

    Chondroitin sulfate (CS) is a glycosaminoglycan (GAG) composed of alternating N-acetyl galactosamine and glucuronic acid units within disaccharide building blocks. CS is a key functional component in proteoglycans of cartilaginous tissues. Owing to its numerous biological roles, CS is widely explored in the pharmaceutical market as nutraceutical ingredient commonly utilized against arthritis, osteoarthrosis, and sometimes osteoporosis. Tissues like shark cartilage and bovine trachea are common sources of CS. Nonetheless, a new CS type has been introduced and investigated in the last few decades in what regards its medical potentials. It is named fucosylated chondroitin sulfate (FucCS). This less common CS type is isolated exclusively from the body wall of sea cucumbers. The presence of fucosyl branching units in the holothurian FucCS gives to this unique GAG, therapeutic properties in various pathophysiological systems which are inexistent in the common CS explored in the market. Examples of these systems are coagulation, thrombosis, hemodialysis, atherosclerosis, cellular growth, angiogenesis, fibrosis, tumor growth, inflammation, viral and protozoan infections, hyperglycemia, diabetes-related pathological events and tissue damage. This report aims at describing the medical benefits gained upon fucosylation of CS. Clinical prospects of these medical benefits are also discussed herein.

  11. The agmatine-containing poly(amidoamine) polymer AGMA1 binds cell surface heparan sulfates and prevents attachment of mucosal human papillomaviruses.

    PubMed

    Cagno, Valeria; Donalisio, Manuela; Bugatti, Antonella; Civra, Andrea; Cavalli, Roberta; Ranucci, Elisabetta; Ferruti, Paolo; Rusnati, Marco; Lembo, David

    2015-09-01

    The agmatine-containing poly(amidoamine) polymer AGMA1 was recently shown to inhibit the infectivity of several viruses, including human papillomavirus 16 (HPV-16), that exploit cell surface heparan sulfate proteoglycans (HSPGs) as attachment receptors. The aim of this work was to assess the antiviral activity of AGMA1 and its spectrum of activity against a panel of low-risk and high-risk HPVs and to elucidate its mechanism of action. AGMA1 was found to be a potent inhibitor of mucosal HPV types (i.e., types 16, 31, 45, and 6) in pseudovirus-based neutralization assays. The 50% inhibitory concentration was between 0.34 μg/ml and 0.73 μg/ml, and no evidence of cytotoxicity was observed. AGMA1 interacted with immobilized heparin and with cellular heparan sulfates, exerting its antiviral action by preventing virus attachment to the cell surface. The findings from this study indicate that AGMA1 is a leading candidate compound for further development as an active ingredient of a topical microbicide against HPV and other sexually transmitted viral infections. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  12. [Biotechnological aspects in "loco" larvae].

    PubMed

    Inestrosa, N C; Labarca, R; Perelman, A; Campos, E O; Araneda, R; González, M; Brandan, E; Sánchez, J P; González-Plaza, R

    1990-10-01

    The biology of planktotrophic larvae of Concholepas concholepas is the main bottleneck towards developing biotechnologies to rear this muricid. Data concerning planktonic larvae development, diets and environmental signals triggering larval settlement and recruitment is scarce. We have begun the study of the molecular and cell biology of embryos, larvae and recruits having as a final goal, the development of appropriate biotechnologies to rear this gastropod. First, an inverse ratio between BuChE and AChE enzyme activities was established. This ratio may be a precise developmental marker for this species. Second, for the first time a phosphoinositide related regulatory pathway is reported in a muricid, opening a new approach to the biotechnological management of larvae. Third, the relation between sulfate in sea water and larval motility was studied. Concentrations below 125 microM sulfate decreases larval motility. The sulfate is incorporated in proteoglycans which participate in different developmental phenomena. Lastly, a genomic Concholepas concholepas DNA sequence, similar to that of a human growth hormone probe was detected. This is very interesting since growth factors are key molecules during development, growth and are involved in food conversion rates in fish and also, in a variety of marine invertebrates.

  13. The heparan sulfate-modifying enzyme glucuronyl C5-epimerase HSE-5 controls Caenorhabditis elegans Q neuroblast polarization during migration.

    PubMed

    Wang, Xiangming; Liu, Jianhong; Zhu, Zhiwen; Ou, Guangshuo

    2015-03-15

    Directional cell migration is fundamental for neural development, and extracellular factors are pivotal for this process. Heparan sulfate proteoglycans (HSPGs) that carry long chains of differentially modified sugar residues contribute to extracellular matrix; however, the functions of HSPG in guiding cell migration remain elusive. Here, we used the Caenorhabditis elegans mutant pool from the Million Mutation Project and isolated a mutant allele of the heparan sulfate-modifying enzyme glucuronyl C5-epimerase HSE-5. Loss-of-function of this enzyme resulted in defective Q neuroblast migration. We showed that hse-5 controlled Q cell migration in a cell non-autonomous manner. By performing live cell imaging in hse-5 mutant animals, we found that hse-5 controlled initial polarization during Q neuroblast migration. Furthermore, our genetic epistasis analysis demonstrated that lon-2 might act downstream of hse-5. Finally, rescue of the hse-5 mutant phenotype by expression of human and mouse hse-5 homologs suggested a conserved function for this gene in neural development. Taken together, our results indicated that proper HSPG modification in the extracellular matrix by HSE-5 is essential for neuroblast polarity during migration. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Heparan Sulfate Differences in Rheumatoid Arthritis versus Healthy Sera

    PubMed Central

    López-Hoyos, Marcos; Seo, Youjin; Andaya, Armann; Leary, Julie A.

    2015-01-01

    Heparan sulfate (HS) is a complex and highly variable polysaccharide, expressed ubiquitously on the cell surface as HS proteoglycans (HSPGs), and found in the extracellular matrix as free HS fragments. Its heterogeneity due to various acetylation and sulfation patterns endows a multitude of functions. In animal tissues, HS interacts with a wide range of proteins to mediate numerous biological activities; given its multiple roles in inflammation processes, characterization of HS in human serum has significant potential for elucidating disease mechanisms. Historically, investigation of HS was limited by its low concentration in human serum, together with the complexity of the serum matrix. In this study, we used a modified mass spectrometry method to examine HS disaccharide profiles in the serum of 50 women with rheumatoid arthritis (RA), and compared our results to 51 sera from healthy women. Using various purification methods and online LC-MS/MS, we discovered statistically significant differences in the sulfation and acetylation patterns between populations. Since early diagnosis of RA is considered important in decelerating the disease's progression, identification of specific biomolecule characterizations may provide crucial information towards developing new therapies for suppressing the disease in its early stages. This is the first report of potential glycosaminoglycan biomarkers for RA found in human sera, while acknowledging the obvious fact that a larger population set, and more stringent collection parameters, will need to be investigated in the future. PMID:25217862

  15. Surface glycosaminoglycans mediate adherence between HeLa cells and Lactobacillus salivarius Lv72.

    PubMed

    Martín, Rebeca; Martín, Carla; Escobedo, Susana; Suárez, Juan E; Quirós, Luis M

    2013-09-17

    The adhesion of lactobacilli to the vaginal surface is of paramount importance to develop their probiotic functions. For this reason, the role of HeLa cell surface proteoglycans in the attachment of Lactobacillus salivarius Lv72, a mutualistic strain of vaginal origin, was investigated. Incubation of cultures with a variety of glycosaminoglycans (chondroitin sulfate A and C, heparin and heparan sulfate) resulted in marked binding interference. However, no single glycosaminoglycan was able to completely abolish cell binding, the sum of all having an additive effect that suggests cooperation between them and recognition of specific adhesins on the bacterial surface. In contrast, chondroitin sulfate B enhanced cell to cell attachment, showing the relevance of the stereochemistry of the uronic acid and the sulfation pattern on binding. Elimination of the HeLa surface glycosaminoglycans with lyases also resulted in severe adherence impairment. Advantage was taken of the Lactobacillus-glycosaminoglycans interaction to identify an adhesin from the bacterial surface. This protein, identify as a soluble binding protein of an ABC transporter system (OppA) by MALDI-TOF/(MS), was overproduced in Escherichia coli, purified and shown to interfere with L. salivarius Lv72 adhesion to HeLa cells. These data suggest that glycosaminoglycans play a fundamental role in attachment of mutualistic bacteria to the epithelium that lines the cavities where the normal microbiota thrives, OppA being a bacterial adhesin involved in the process.

  16. Sulfation and Cation Effects on the Conformational Properties of the Glycan Backbone of Chondroitin Sulfate Disaccharides

    PubMed Central

    Faller, Christina E.; Guvench, Olgun

    2015-01-01

    Chondroitin sulfate (CS) is one of several glycosaminoglycans that are major components of proteoglycans. A linear polymer consisting of repeats of the disaccharide -4GlcAβ1-3GalNAcβ1-, CS undergoes differential sulfation resulting in five unique sulfation patterns. Because of the dimer repeat, the CS glycosidic “backbone” has two distinct sets of conformational degrees of freedom defined by pairs of dihedral angles: (ϕ1, ψ1) about the β1-3 glycosidic linkage and (ϕ2, ψ2) about the β1-4 glycosidic linkage. Differential sulfation and the possibility of cation binding, combined with the conformational flexibility and biological diversity of CS, complicate experimental efforts to understand CS three-dimensional structures at atomic resolution. Therefore, all-atom explicit-solvent molecular dynamics simulations with Adaptive Biasing Force sampling of the CS backbone were applied to obtain high resolution, high precision free energies of CS disaccharides as a function of all possible backbone geometries. All ten disaccharides (β1-3 vs. β1-4 linkage x five different sulfation patterns) were studied; additionally, ion effects were investigated by considering each disaccharide in the presence of either neutralizing sodium or calcium cations. GlcAβ1-3GalNAc disaccharides have a single, broad, thermodynamically important free-energy minimum whereas GalNAcβ1-4GlcA disaccharides have two such minima. Calcium cations but not sodium cations bind to the disaccharides, and binding is primarily to the GlcA –COO− moiety as opposed to sulfate groups. This binding alters the glycan backbone thermodynamics in instances where a calcium cation bound to –COO− can act to bridge and stabilize an interaction with an adjacent sulfate group, whereas, in the absence of this cation, the proximity of a sulfate group to –COO− results in two like charges being both desolvated and placed adjacent to each other and is found to be destabilizing. In addition to providing information on sulfation and cation effects, the present results can be applied to building models of CS polymers and as a point of comparison in studies of CS polymer backbone dynamics and thermodynamics. PMID:25906376

  17. Sulfation and cation effects on the conformational properties of the glycan backbone of chondroitin sulfate disaccharides.

    PubMed

    Faller, Christina E; Guvench, Olgun

    2015-05-21

    Chondroitin sulfate (CS) is one of several glycosaminoglycans that are major components of proteoglycans. A linear polymer consisting of repeats of the disaccharide -4GlcAβ1-3GalNAcβ1-, CS undergoes differential sulfation resulting in five unique sulfation patterns. Because of the dimer repeat, the CS glycosidic "backbone" has two distinct sets of conformational degrees of freedom defined by pairs of dihedral angles: (ϕ1, ψ1) about the β1-3 glycosidic linkage and (ϕ2, ψ2) about the β1-4 glycosidic linkage. Differential sulfation and the possibility of cation binding, combined with the conformational flexibility and biological diversity of CS, complicate experimental efforts to understand CS three-dimensional structures at atomic resolution. Therefore, all-atom explicit-solvent molecular dynamics simulations with Adaptive Biasing Force sampling of the CS backbone were applied to obtain high-resolution, high-precision free energies of CS disaccharides as a function of all possible backbone geometries. All 10 disaccharides (β1-3 vs β1-4 linkage × five different sulfation patterns) were studied; additionally, ion effects were investigated by considering each disaccharide in the presence of either neutralizing sodium or calcium cations. GlcAβ1-3GalNAc disaccharides have a single, broad, thermodynamically important free-energy minimum, whereas GalNAcβ1-4GlcA disaccharides have two such minima. Calcium cations but not sodium cations bind to the disaccharides, and binding is primarily to the GlcA -COO(-) moiety as opposed to sulfate groups. This binding alters the glycan backbone thermodynamics in instances where a calcium cation bound to -COO(-) can act to bridge and stabilize an interaction with an adjacent sulfate group, whereas, in the absence of this cation, the proximity of a sulfate group to -COO(-) results in two like charges being both desolvated and placed adjacent to each other and is found to be destabilizing. In addition to providing information on sulfation and cation effects, the present results can be applied to building models of CS polymers and as a point of comparison in studies of CS polymer backbone dynamics and thermodynamics.

  18. Enzyme replacement therapy in newborn mucopolysaccharidosis IVA mice: early treatment rescues bone lesions?

    PubMed Central

    Tomatsu, Shunji; Montaño, Adriana M.; Oikawa, Hirotaka; Dung, Vu Chi; Hashimoto, Amiko; Oguma, Toshihiro; Takahashi, Tatsuo; Shimada, Tsutomu; Orii, Tadao; Sly, William S.

    2014-01-01

    We treated mucopolysaccharidosis IVA (MPS IVA) mice to assess the effects of long-term enzyme replacement therapy (ERT) initiated at birth, since adult mice treated by ERT showed little improvement in bone pathology (1). To conduct ERT in newborn mice, we used recombinant human N-acetylgalactosamine-6-sulfate sulfatase (GALNS) produced in a CHO cell line. First, to observe the tissue distribution pattern, a dose of 250 units/g body weight was administered intravenously in MPS IVA mice at day 2 or 3. The infused enzyme was primarily recovered in liver and spleen, with detectable activity in bone and brain. Second, newborn ERT was conducted after tissue distribution study. The first injection of newborn ERT was performed intravenously, the second to fourth weekly injections were intraperitoneal, and the remaining injections from 5th to 14th week were intravenous into the tail vein. MPS IVA mice treated with GALNS showed clearance of lysosomal storage in liver, spleen, and sinus lining cells in bone marrow. The column structure of the growth plate was organized better than adult mice treated with ERT; however, hyaline and fibrous cartilage cells in femur, spine, ligaments, discs, synovium, and periosteum still had storage materials to some extent. Heart valves were refractory to the treatment. Levels of serum keratan sulfate were kept normal in newborn ERT mice. In conclusion, the enzyme, which enters the cartilage before the cartilage cell layer becomes mature, prevents disorganization of column structure. Early treatment from birth leads to partial remission of bone pathology in MPS IVA mouse. PMID:24953405

  19. Characteristics of Mitochondrial Transformation into Human Cells

    PubMed Central

    Kesner, E. E.; Saada-Reich, A.; Lorberboum-Galski, H.

    2016-01-01

    Mitochondria can be incorporated into mammalian cells by simple co-incubation of isolated mitochondria with cells, without the need of transfection reagents or any other type of intervention. This phenomenon was termed mitochondrial transformation, and although it was discovered in 1982, currently little is known regarding its mechanism(s). Here we demonstrate that mitochondria can be transformed into recipient cells very quickly, and co-localize with endogenous mitochondria. The isolated mitochondria interact directly with cells, which engulf the mitochondria with cellular extensions in a way, which may suggest the involvement of macropinocytosis or macropinocytosis-like mechanisms in mitochondrial transformation. Indeed, macropinocytosis inhibitors but not clathrin-mediated endocytosis inhibition-treatments, blocks mitochondria transformation. The integrity of the mitochondrial outer membrane and its proteins is essential for the transformation of the mitochondria into cells; cells can distinguish mitochondria from similar particles and transform only intact mitochondria. Mitochondrial transformation is blocked in the presence of the heparan sulfate molecules pentosan polysulfate and heparin, which indicate crucial involvement of cellular heparan sulfate proteoglycans in the mitochondrial transformation process. PMID:27184109

  20. The Compact and Biologically Relevant Structure of Inter-α-inhibitor Is Maintained by the Chondroitin Sulfate Chain and Divalent Cations.

    PubMed

    Scavenius, Carsten; Nikolajsen, Camilla Lund; Stenvang, Marcel; Thøgersen, Ida B; Wyrożemski, Łukasz; Wisniewski, Hans-Georg; Otzen, Daniel E; Sanggaard, Kristian W; Enghild, Jan J

    2016-02-26

    Inter-α-inhibitor is a proteoglycan of unique structure. The protein consists of three subunits, heavy chain 1, heavy chain 2, and bikunin covalently joined by a chondroitin sulfate chain originating at Ser-10 of bikunin. Inter-α-inhibitor interacts with an inflammation-associated protein, tumor necrosis factor-inducible gene 6 protein, in the extracellular matrix. This interaction leads to transfer of the heavy chains from the chondroitin sulfate of inter-α-inhibitor to hyaluronan and consequently to matrix stabilization. Divalent cations and heavy chain 2 are essential co-factors in this transfer reaction. In the present study, we have investigated how divalent cations in concert with the chondroitin sulfate chain influence the structure and stability of inter-α-inhibitor. The results showed that Mg(2+) or Mn(2+), but not Ca(2+), induced a conformational change in inter-α-inhibitor as evidenced by a decrease in the Stokes radius and a bikunin chondroitin sulfate-dependent increase of the thermodynamic stability. This structure was shown to be essential for the ability of inter-α-inhibitor to participate in extracellular matrix stabilization. In addition, the data revealed that bikunin was positioned adjacent to both heavy chains and that the two heavy chains also were in close proximity. The chondroitin sulfate chain interacted with all protein components and inter-α-inhibitor dissociated when it was degraded. Conventional purification protocols result in the removal of the Mg(2+) found in plasma and because divalent cations influence the conformation and affect function it is important to consider this when characterizing the biological activity of inter-α-inhibitor. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Involvement of Receptor-like Protein Tyrosine Phosphatase ζ/RPTPβ and Its Ligand Pleiotrophin/Heparin-binding Growth-associated Molecule (HB-GAM) in Neuronal Migration

    PubMed Central

    Maeda, Nobuaki; Noda, Masaharu

    1998-01-01

    Pleiotrophin/heparin-binding growth-associated molecule (HB-GAM) is a specific ligand of protein tyrosine phosphatase ζ (PTPζ)/receptor-like protein tyrosine phosphatase β (RPTPβ) expressed in the brain as a chondroitin sulfate proteoglycan. Pleiotrophin and PTPζ isoforms are localized along the radial glial fibers, a scaffold for neuronal migration, suggesting that these molecules are involved in migratory processes of neurons during brain development. In this study, we examined the roles of pleiotrophin-PTPζ interaction in the neuronal migration using cell migration assay systems with glass fibers and Boyden chambers. Pleiotrophin and poly-l-lysine coated on the substratums stimulated cell migration of cortical neurons, while laminin, fibronectin, and tenascin exerted almost no effect. Pleiotrophin-induced and poly-l-lysine–induced neuronal migrations showed significant differences in sensitivity to various molecules and reagents. Polyclonal antibodies against the extracellular domain of PTPζ, PTPζ-S, an extracellular secreted form of PTPζ, and sodium vanadate, a protein tyrosine phosphatase inhibitor, added into the culture medium strongly suppressed specifically the pleiotrophin-induced neuronal migration. Furthermore, chondroitin sulfate C but not chondroitin sulfate A inhibited pleiotrophin-induced neuronal migration, in good accordance with our previous findings that chondroitin sulfate constitutes a part of the pleiotrophin-binding site of PTPζ, and PTPζ-pleiotrophin binding is inhibited by chondroitin sulfate C but not by chondroitin sulfate A. Immunocytochemical analysis indicated that the transmembrane forms of PTPζ are expressed on the migrating neurons especially at the lamellipodia along the leading processes. These results suggest that PTPζ is involved in the neuronal migration as a neuronal receptor of pleiotrophin distributed along radial glial fibers. PMID:9660874

  2. Expanding the role of 3-O sulfated heparan sulfate in herpes simplex virus type-1 entry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O'Donnell, Christopher D., E-mail: codonn3@uic.ed; Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612; Kovacs, Maria, E-mail: marcsika101@yahoo.co

    2010-02-20

    Heparan sulfate (HS) proteoglycans are commonly exploited by multiple viruses for initial attachment to host cells. Herpes simplex virus-1 (HSV-1) is unique because it can use HS for both attachment and penetration, provided specific binding sites for HSV-1 envelope glycoprotein gD are present. The interaction with gD is mediated by specific HS moieties or 3-O sulfated HS (3-OS HS), which are generated by all but one of the seven isoforms of 3-O sulfotransferases (3-OSTs). Here we demonstrate that several common experimental cell lines express unique sets of 3-OST isoforms. While the isoforms 3-OST-3, -5 and -6 were most commonly expressed,more » isoforms 3-OST-2 and -4 were undetectable in the cell lines examined. Since most cell lines expressed multiple 3-OST isoforms, we addressed the significance of 3-OS HS in HSV-1 entry by down-regulating 2-O-sulfation, a prerequisite for 3-OS HS formation, by knocking down 2-OST expression by RNA interference (RNAi). 2-OST knockdown was verified by reverse-transcriptase PCR and Western blot analysis, while 3-OS HS knockdown was verified by immunofluorescence. Cells showed a significant decrease in viral entry, suggesting an important role for 3-OS HS. Implicating 3-OS HS further, cells knocked down for 2-OST expression also demonstrated decreased cell-cell fusion when cocultivated with effector cells transfected with HSV-1 glycoproteins. Our findings suggest that 3-OS HS may play an important role in HSV-1 entry into many different cell lines.« less

  3. DSE promotes aggressive glioma cell phenotypes by enhancing HB-EGF/ErbB signaling.

    PubMed

    Liao, Wen-Chieh; Liao, Chih-Kai; Tsai, You-Huan; Tseng, To-Jung; Chuang, Li-Ching; Lan, Chyn-Tair; Chang, Hung-Ming; Liu, Chiung-Hui

    2018-01-01

    Remodeling of the extracellular matrix (ECM) in the tumor microenvironment promotes glioma progression. Chondroitin sulfate (CS) proteoglycans appear in the ECM and on the cell surface, and can be catalyzed by dermatan sulfate epimerase to form chondroitin sulfate/dermatan sulfate (CS/DS) hybrid chains. Dermatan sulfate epimerase 1 (DSE) is overexpressed in many types of cancer, and CS/DS chains mediate several growth factor signals. However, the role of DSE in gliomas has never been explored. In the present study, we determined the expression of DSE in gliomas by consulting a public database and conducting immunohistochemistry on a tissue array. Our investigation revealed that DSE was upregulated in gliomas compared with normal brain tissue. Furthermore, high DSE expression was associated with advanced tumor grade and poor survival. We found high DSE expression in several glioblastoma cell lines, and DSE expression directly mediated DS chain formation in glioblastoma cells. Knockdown of DSE suppressed the proliferation, migration, and invasion of glioblastoma cells. In contrast, overexpression of DSE in GL261 cells enhanced these malignant phenotypes and in vivo tumor growth. Interestingly, we found that DSE selectively regulated heparin-binding EGF-like growth factor (HB-EGF)-induced signaling in glioblastoma cells. Inhibiting epidermal growth factor receptor (EGFR) and ErbB2 with afatinib suppressed DSE-enhanced malignant phenotypes, establishing the critical role of the ErbB pathway in regulating the effects of DSE expression. This evidence indicates that upregulation of DSE in gliomas contributes to malignant behavior in cancer cells. We provide novel insight into the significance of DS chains in ErbB signaling and glioma pathogenesis.

  4. Structural and Functional Components of the Skate Sensory Organ Ampullae of Lorenzini.

    PubMed

    Zhang, Xing; Xia, Ke; Lin, Lei; Zhang, Fuming; Yu, Yanlei; St Ange, Kalib; Han, Xiaorui; Edsinger, Eric; Sohn, Joel; Linhardt, Robert J

    2018-05-09

    The skate, a cartilaginous fish related to sharks and rays, possesses a unique electrosensitive sensory organ known as the ampullae of Lorenzini (AoL). This organ is responsible for the detection of weak electric field changes caused by the muscle contractions of their prey. While keratan sulfate (KS) is believed to be a component of a jelly that fills this sensory organ and has been credited with its high proton conductivity, modern analytical methods have not been applied to its characterization. Surprisingly, total glycosaminoglycan (GAG) analysis demonstrates that the KS from skate jelly is extraordinarily pure, containing no other GAGs. This KS had a molecular weight of 20 to 30 kDa, consisting primarily of N-linked KS comprised mostly of a monosulfated disaccharide repeating unit, →3) Gal (1→4) GlcNAc6S (1→. Proteomic analysis of AoL jelly suggests that transferrin, keratin, and mucin serve as KS core proteins. Actin and tropomyosin are responsible for assembling the macrostructure of the jelly, and parvalbumin α-like protein and calreticulin regulate calcium and potassium channels involved in the transduction of the electrical signal, once conducted down the AoL by the jelly, serving as the molecular basis for electroreception.

  5. The Effects of Oxygen Level and Glucose Concentration on the Metabolism of Porcine TMJ Disc Cells

    PubMed Central

    Cisewski, Sarah E.; Zhang, Lixia; Kuo, Jonathan; Wright, Gregory J.; Wu, Yongren; Kern, Michael J.; Yao, Hai

    2015-01-01

    Objective To determine the combined effect of oxygen level and glucose concentration on cell viability, ATP production, and matrix synthesis of temporomandibular joint (TMJ) disc cells. Design TMJ disc cells were isolated from pigs aged 6-8 months and cultured in a monolayer. Cell cultures were preconditioned for 48 hours with 0, 1.5, 5, or 25mM glucose DMEM under 1%, 5%, 10%, or 21% O2 level, respectively. The cell viability was measured using the WST-1 assay. ATP production was determined using the Luciferin-Luciferase assay. Collagen and proteoglycan synthesis were determined by measuring the incorporation of [2, 3-3H]proline and [35S]sulfate into the cells, respectively. Results TMJ disc cell viability significantly decreased (P<0.0001) without glucose. With glucose present, decreased oxygen levels significantly increased viability (P<0.0001), while a decrease in glucose concentration significantly decreased viability (P<0.0001). With glucose present, decreasing oxygen levels significantly reduced ATP production (P<0.0001) and matrix synthesis (P<0.0001). A decreased glucose concentration significantly decreased collagen synthesis (P<0.0001). The interaction between glucose and oxygen was significant in regards to cell viability (P<0.0001), ATP production (P=0.00015), and collagen (P=0.0002) and proteoglycan synthesis (P<0.0001). Conclusions Although both glucose and oxygen are important, glucose is the limiting nutrient for TMJ disc cell survival. At low oxygen levels, the production of ATP, collagen, and proteoglycan are severely inhibited. These results suggest that steeper nutrient gradients may exist in the TMJ disc and it may be vulnerable to pathological events that impede nutrient supply. PMID:26033165

  6. The effects of oxygen level and glucose concentration on the metabolism of porcine TMJ disc cells.

    PubMed

    Cisewski, S E; Zhang, L; Kuo, J; Wright, G J; Wu, Y; Kern, M J; Yao, H

    2015-10-01

    To determine the combined effect of oxygen level and glucose concentration on cell viability, ATP production, and matrix synthesis of temporomandibular joint (TMJ) disc cells. TMJ disc cells were isolated from pigs aged 6-8 months and cultured in a monolayer. Cell cultures were preconditioned for 48 h with 0, 1.5, 5, or 25 mM glucose DMEM under 1%, 5%, 10%, or 21% O2 level, respectively. The cell viability was measured using the WST-1 assay. ATP production was determined using the Luciferin-Luciferase assay. Collagen and proteoglycan synthesis were determined by measuring the incorporation of [2, 3-(3)H] proline and [(35)S] sulfate into the cells, respectively. TMJ disc cell viability significantly decreased (P < 0.0001) without glucose. With glucose present, decreased oxygen levels significantly increased viability (P < 0.0001), while a decrease in glucose concentration significantly decreased viability (P < 0.0001). With glucose present, decreasing oxygen levels significantly reduced ATP production (P < 0.0001) and matrix synthesis (P < 0.0001). A decreased glucose concentration significantly decreased collagen synthesis (P < 0.0001). The interaction between glucose and oxygen was significant in regards to cell viability (P < 0.0001), ATP production (P = 0.00015), and collagen (P = 0.0002) and proteoglycan synthesis (P < 0.0001). Although both glucose and oxygen are important, glucose is the limiting nutrient for TMJ disc cell survival. At low oxygen levels, the production of ATP, collagen, and proteoglycan are severely inhibited. These results suggest that steeper nutrient gradients may exist in the TMJ disc and it may be vulnerable to pathological events that impede nutrient supply. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  7. T1ρ Dispersion in Articular Cartilage

    PubMed Central

    Besier, Thor F.; Pauly, John M.; Smith, R. Lane; Delp, Scott L.; Beaupre, Gary S.; Gold, Garry E.

    2015-01-01

    Objective This study assessed T1ρ relaxation dispersion, measured by magnetic resonance imaging (MRI), as a tool to noninvasively evaluate cartilage material and biochemical properties. The specific objective was to answer two questions: (1) does cartilage initial elastic modulus (E0) correlate with T1ρ dispersion effects and (2) does collagen or proteoglycan content correlate with T1ρ dispersion effects? Design Cadaveric patellae with and without visible cartilage damage on conventional MR were included. T2 and T1ρ relaxation times at 500 and 1000 Hz spin-lock field amplitudes were measured. We estimated T1ρ dispersion effects by measuring T1ρ relaxation time at 500 and 1000 Hz and T2 relaxation time and using a new tool, the ratio T1ρ/T2. Cartilage initial elastic modulus, E0, was measured from initial response of mechanical indentation creep tests. Collagen and proteoglycan contents were measured at the indentation test sites; proteoglycan content was measured by their covalently linked sulfated glycosaminoglycans (sGAG). Pearson correlation coefficients were determined, taking into account the clustering of multiple samples within a single patella specimen. Results Cartilage initial elastic modulus, E0, increased with decreasing values of T1ρ/T2 measurements at both 500 Hz (P = 0.034) and 1000 Hz (P = 0.022). 1/T1ρ relaxation time (500 Hz) increased with increasing sGAG content (P = 0.041). Conclusions T1ρ/T2 ratio, a new tool, and cartilage initial elastic modulus are both measures of water–protein interactions, are dependent on the cartilage structure, and were correlated in this study. PMID:26069714

  8. Aging and oxidative stress reduce the response of human articular chondrocytes to insulin-like growth factor 1 and osteogenic protein 1.

    PubMed

    Loeser, Richard F; Gandhi, Uma; Long, David L; Yin, Weihong; Chubinskaya, Susan

    2014-08-01

    To determine the effects of aging and oxidative stress on the response of human articular chondrocytes to insulin-like growth factor 1 (IGF-1) and osteogenic protein 1 (OP-1). Chondrocytes isolated from normal articular cartilage obtained from tissue donors were cultured in alginate beads or monolayer. Cells were stimulated with 50-100 ng/ml of IGF-1, OP-1, or both. Oxidative stress was induced using tert-butyl hydroperoxide. Sulfate incorporation was used to measure proteoglycan synthesis, and immunoblotting of cell lysates was performed to analyze cell signaling. Confocal microscopy was performed to measure nuclear translocation of Smad4. Chondrocytes isolated from the articular cartilage of tissue donors ranging in age from 24 years to 81 years demonstrated an age-related decline in proteoglycan synthesis stimulated by IGF-1 and IGF-1 plus OP-1. Induction of oxidative stress inhibited both IGF-1- and OP-1-stimulated proteoglycan synthesis. Signaling studies showed that oxidative stress inhibited IGF-1-stimulated Akt phosphorylation while increasing phosphorylation of ERK, and that these effects were greater in cells from older donors. Oxidative stress also increased p38 phosphorylation, which resulted in phosphorylation of Smad1 at the Ser(206) inhibitory site and reduced nuclear accumulation of Smad1. Oxidative stress also modestly reduced OP-1-stimulated nuclear translocation of Smad4. These results demonstrate an age-related reduction in the response of human chondrocytes to IGF-1 and OP-1, which are 2 important anabolic factors in cartilage, and suggest that oxidative stress may be a contributing factor by altering IGF-1 and OP-1 signaling. Copyright © 2014 by the American College of Rheumatology.

  9. An immunohistochemical study of the triangular fibrocartilage complex of the wrist: regional variations in cartilage phenotype

    PubMed Central

    Milz, S; Sicking, B; Sprecher, C M; Putz, R; Benjamin, M

    2007-01-01

    The triangular fibrocartilage complex (TFCC) transmits load from the wrist to the ulna and stabilizes the distal radioulnar joint. Damage to it is a major cause of wrist pain. Although its basic structure is well established, little is known of its molecular composition. We have analysed the immunohistochemical labelling pattern of the extracellular matrix of the articular disc and the meniscal homologue of the TFCC in nine elderly individuals (age range 69–96 years), using a panel of monoclonal antibodies directed against collagens, glycosaminoglycans, proteoglycans and cartilage oligomeric matrix protein (COMP). Although many of the molecules (types I, III and VI collagen, chondroitin 4 sulphate, dermatan sulphate and keratan sulphate, the oversulphated epitope of chondroitin 6 sulphate, versican and COMP) were found in all parts of the TFCC, aggrecan, link protein and type II collagen were restricted to the articular disc and to entheses. They were thus not a feature of the meniscal homologue. The shift in tissue phenotype within the TFCC, from a fibrocartilaginous articular disc to a more fibrous meniscal homologue, correlates with biomechanical data suggesting that the radial region is stiff and subject to considerable stress concentration. The presence of aggrecan, link protein and type II collagen in the articular disc could explain why the TFCC is destroyed in rheumatoid arthritis, given that it has been suggested that autoimmunity to these antigens results in the destruction of articular cartilage. The differential distribution of aggrecan within the TFCC is likely to be reflected by regional differences in water content and mobility on the radial and ulnar side. This needs to be taken into account in the design of improved MRI protocols for visualizing this ulnocarpal complex of the wrist. PMID:17532798

  10. Cell growth and migration under octenidine-antiseptic treatment.

    PubMed

    Jenull, S; Hojdar, K; Laggner, H; Velimirov, B; Zemann, N; Huettinger, M

    2015-06-01

    The toxicity of octenidine antiseptics in cultured cells contrasts their good tolerability in tissue. This phenomenon prompted us to examine which cell culture conditions allow survival and proliferation and to investigate a possible modulation of toxicity by the extracellular matrix proteoglycan chondroitin sulfate. We tested fibroblasts and MCF7 cells for growth using the MTT test, and assessed wound healing potency with a laceration assay. Expression levels of the genes involved in controlling wound healing were assessed with RT-PCR. A 24 hour exposure to the octenidine-based solution was found incompatible with cell growth. When octenidine solution (0.5-0.5mg/l) was coated on dishes, growth was profoundly reduced after 24 hours, however there was no cytotoxic effect at 0.012 mg/l. Interestingly, when dishes were first coated with chondroitin sulfate the cytotoxicity of octenidine-based solution was modulated. Cell migration was not inhibited by octenidine-based solution treatment (2 minutes; 15 mg/l). No significant changes in gene expression levels in response to the octenidine-based solution treatment were detected. In cell culture conditions application of the octenidine-based solution without toxicity can be observed, comparable to the minimal application required to give full bactericidal effect. Alteration of toxicity by interaction with chondroitin sulfate in cell culture suggests a similar function for extraceullar matrix in intact tissue.

  11. Sulfated Glycans and Related Digestive Enzymes in the Zika Virus Infectivity: Potential Mechanisms of Virus-Host Interaction and Perspectives in Drug Discovery.

    PubMed

    Pomin, Vitor H

    2017-01-01

    As broadly reported, there is an ongoing Zika virus (ZIKV) outbreak in countries of Latin America. Recent findings have demonstrated that ZIKV causes severe defects on the neural development in fetuses in utero and newborns. Very little is known about the molecular mechanisms involved in the ZIKV infectivity. Potential therapeutic agents are also under investigation. In this report, the possible mechanisms of action played by glycosaminoglycans (GAGs) displayed at the surface proteoglycans of host cells, and likely in charge of interactions with surface proteins of the ZIKV, are highlighted. As is common for the most viruses, these sulfated glycans serve as receptors for virus attachment onto the host cells and consequential entry during infection. The applications of (1) exogenous sulfated glycans of different origins and chemical structures capable of competing with the virus attachment receptors (supposedly GAGs) and (2) GAG-degrading enzymes able to digest the virus attachment receptors on the cells may be therapeutically beneficial as anti-ZIKV. This communication attempts, therefore, to offer some guidance for the future research programs aimed to unveil the molecular mechanisms underlying the ZIKV infectivity and to develop therapeutics capable of decreasing the devastating consequences caused by ZIKV outbreak in the Americas.

  12. Inhibition of Human Metapneumovirus Binding to Heparan Sulfate Blocks Infection in Human Lung Cells and Airway Tissues

    PubMed Central

    Klimyte, Edita M.; Smith, Stacy E.; Oreste, Pasqua; Lembo, David

    2016-01-01

    ABSTRACT Human metapneumovirus (HMPV), a recently discovered paramyxovirus, infects nearly 100% of the world population and causes severe respiratory disease in infants, the elderly, and immunocompromised patients. We previously showed that HMPV binds heparan sulfate proteoglycans (HSPGs) and that HMPV binding requires only the viral fusion (F) protein. To characterize the features of this interaction critical for HMPV binding and the role of this interaction in infection in relevant models, we utilized sulfated polysaccharides, heparan sulfate mimetics, and occluding compounds. Iota-carrageenan demonstrated potent anti-HMPV activity by inhibiting binding to lung cells mediated by the F protein. Furthermore, analysis of a minilibrary of variably sulfated derivatives of Escherichia coli K5 polysaccharide mimicking the HS structure revealed that the highly O-sulfated K5 polysaccharides inhibited HMPV infection, identifying a potential feature of HS critical for HMPV binding. The peptide dendrimer SB105-A10, which binds HS, reduced binding and infection in an F-dependent manner, suggesting that occlusion of HS at the target cell surface is sufficient to prevent infection. HMPV infection was also inhibited by these compounds during apical infection of polarized airway tissues, suggesting that these interactions take place during HMPV infection in a physiologically relevant model. These results reveal key features of the interaction between HMPV and HS, supporting the hypothesis that apical HS in the airway serves as a binding factor during infection, and HS modulating compounds may serve as a platform for potential antiviral development. IMPORTANCE Human metapneumovirus (HMPV) is a paramyxovirus that causes respiratory disease worldwide. It has been previously shown that HMPV requires binding to heparan sulfate on the surfaces of target cells for attachment and infection. In this study, we characterize the key features of this binding interaction using heparan sulfate mimetics, identify an important sulfate modification, and demonstrate that these interactions occur at the apical surface of polarized airway tissues. These findings provide insights into the initial binding step of HMPV infection that has potential for antiviral development. PMID:27489270

  13. Electrostatic Interactions Between Glycosaminoglycan Molecules

    NASA Astrophysics Data System (ADS)

    Song, Fan; Moyne, Christian; Bai, Yi-Long

    2005-02-01

    The electrostatic interactions between nearest-neighbouring chondroitin sulfate glycosaminoglycan (CS-GAG) molecular chains are obtained on the bottle brush conformation of proteoglycan aggrecan based on an asymptotic solution of the Poisson-Boltzmann equation the CS-GAGs satisfy under the physiological conditions of articular cartilage. The present results show that the interactions are associated intimately with the minimum separation distance and mutual angle between the molecular chains themselves. Further analysis indicates that the electrostatic interactions are not only expressed to be purely exponential in separation distance and decrease with the increasing mutual angle but also dependent sensitively on the saline concentration in the electrolyte solution within the tissue, which is in agreement with the existed relevant conclusions.

  14. Collagen Fibrils and Proteoglycans of Macular Dystrophy Cornea: Ultrastructure and 3D Transmission Electron Tomography.

    PubMed

    Akhtar, Saeed; Alkatan, Hind M; Kirat, Omar; Khan, Adnan A; Almubrad, Turki

    2015-06-01

    We report the ultrastructure and 3D transmission electron tomography of collagen fibrils (CFs), proteoglycans (PGs), and microfibrils within the CF of corneas of patients with macular corneal dystrophy (MCD). Three normal corneas and three MCD corneas from three Saudi patients (aged 25, 31, and 49 years, respectively) were used for this study. The corneas were processed for light and electron microscopy studies. 3D images were composed from a set of 120 ultrastructural images using the program "Composer" and visualized using the program "Visuliser Kai". 3D image analysis of MCD cornea showed a clear organization of PGs around the CF at very high magnification and degeneration of the microfibrils within the CF. Within the MCD cornea, the PG area in the anterior stroma was significantly larger than in the middle and posterior stroma. The PG area in the MCD cornea was significantly larger compared with the PG area in the normal cornea. The CF diameter and inter-fibrillar spacing of the MCD cornea were significantly smaller compared with those of the normal cornea. Ultrastructural 3D imaging showed that the production of unsulfated keratin sulfate (KS) may lead to the degeneration of micro-CFs within the CFs. The effect of the unsulfated KS was higher in the anterior stroma compared with the posterior stroma.

  15. Immunophenotypes of macular corneal dystrophy in India and correlation with mutations in CHST6.

    PubMed

    Sultana, Afia; Klintworth, Gordon K; Thonar, Eugene J-M A; Vemuganti, Geeta K; Kannabiran, Chitra

    2009-01-01

    To determine the immunophenotypes of macular corneal dystrophy (MCD) in Indian patients and to correlate them with mutations in the carbohydrate 6-sulfotransferase (CHST6) gene. Sixty-four patients from 53 families with MCD that were previously screened for mutations in CHST6 were included in an immunophenotype analysis. Antigenic keratan sulfate (AgKS) in serum as well as corneal tissue was evaluated in 31 families. Only cornea was evaluated in 11 families, and only serum was evaluated in 11 families. AgKS was detected in formalin-fixed, paraffin-embedded corneal sections by immunohistochemistry and in serum by ELISA using a monoclonal antibody against sulfated forms of KS in patients with MCD as well as normal controls. Analysis of corneal and/or serum AgKS disclosed MCD type I (27 families), MCD type IA (5 families), and MCD type II (3 families) in the cases studied. An additional 10 families were either MCD type I or MCD type IA since only serum AgKS data were available. Seven families manifested atypical immunophenotypes since the corneal AgKS expression was either of MCD type I or MCD type IA, but serum AgKS levels ranged from 19 ng/ml to 388 ng/ml. More than one immunophenotype was detected amongst siblings in two families. Each immunophenotype was associated with mutational heterogeneity in CHST6. MCD type I was the predominant immunophenotype in the Indian population studied followed by MCD type IA and then MCD type II. We detected further immunophenotypic heterogeneity by finding atypical patterns of AgKS reactivity in a subset of families. There were no simple correlations between immunophenotypes and specific mutations in CHST6, suggesting that factors other than CHST6 mutations may be contributing to the immunophenotypes in MCD.

  16. Systems biology analysis of hepatitis C virus infection reveals the role of copy number increases in regions of chromosome 1q in hepatocellular carcinoma metabolism.

    PubMed

    Elsemman, Ibrahim E; Mardinoglu, Adil; Shoaie, Saeed; Soliman, Taysir H; Nielsen, Jens

    2016-04-26

    Hepatitis C virus (HCV) infection is a worldwide healthcare problem; however, traditional treatment methods have failed to cure all patients, and HCV has developed resistance to new drugs. Systems biology-based analyses could play an important role in the holistic analysis of the impact of HCV on hepatocellular metabolism. Here, we integrated HCV assembly reactions with a genome-scale hepatocyte metabolic model to identify metabolic targets for HCV assembly and metabolic alterations that occur between different HCV progression states (cirrhosis, dysplastic nodule, and early and advanced hepatocellular carcinoma (HCC)) and healthy liver tissue. We found that diacylglycerolipids were essential for HCV assembly. In addition, the metabolism of keratan sulfate and chondroitin sulfate was significantly changed in the cirrhosis stage, whereas the metabolism of acyl-carnitine was significantly changed in the dysplastic nodule and early HCC stages. Our results explained the role of the upregulated expression of BCAT1, PLOD3 and six other methyltransferase genes involved in carnitine biosynthesis and S-adenosylmethionine metabolism in the early and advanced HCC stages. Moreover, GNPAT and BCAP31 expression was upregulated in the early and advanced HCC stages and could lead to increased acyl-CoA consumption. By integrating our results with copy number variation analyses, we observed that GNPAT, PPOX and five of the methyltransferase genes (ASH1L, METTL13, SMYD2, TARBP1 and SMYD3), which are all located on chromosome 1q, had increased copy numbers in the cancer samples relative to the normal samples. Finally, we confirmed our predictions with the results of metabolomics studies and proposed that inhibiting the identified targets has the potential to provide an effective treatment strategy for HCV-associated liver disorders.

  17. Allelic variation of the Lyme disease spirochete adhesin DbpA influences spirochetal binding to decorin, dermatan sulfate, and mammalian cells.

    PubMed

    Benoit, Vivian M; Fischer, Joshua R; Lin, Yi-Pin; Parveen, Nikhat; Leong, John M

    2011-09-01

    After transmission by an infected tick, the Lyme disease spirochete, Borrelia burgdorferi sensu lato, colonizes the mammalian skin and may disseminate systemically. The three major species of Lyme disease spirochete--B. burgdorferi sensu stricto, B. garinii, and B. afzelii--are associated with different chronic disease manifestations. Colonization is likely promoted by the ability to bind to target tissues, and Lyme disease spirochetes utilize multiple adhesive molecules to interact with diverse mammalian components. The allelic variable surface lipoprotein decorin binding protein A (DbpA) promotes bacterial binding to the proteoglycan decorin and to the glycosaminoglycan (GAG) dermatan sulfate. To assess allelic variation of DbpA in GAG-, decorin-, and cell-binding activities, we expressed dbpA alleles derived from diverse Lyme disease spirochetes in B. burgdorferi strain B314, a noninfectious and nonadherent strain that lacks dbpA. Each DbpA allele conferred upon B. burgdorferi strain B314 the ability to bind to cultured kidney epithelial (but not glial or endothelial) cells, as well as to purified decorin and dermatan sulfate. Nevertheless, allelic variation of DbpA was associated with dramatic differences in substrate binding activity. In most cases, decorin and dermatan sulfate binding correlated well, but DbpA of B. afzelii strain VS461 promoted differential binding to decorin and dermatan sulfate, indicating that the two activities are separable. DbpA from a clone of B. burgdorferi strain N40 that can cause disseminated infection in mice displayed relatively low adhesive activity, indicating that robust DbpA-mediated adhesive activity is not required for spread in the mammalian host.

  18. Delivering heparin-binding insulin-like growth factor 1 with self-assembling peptide hydrogels.

    PubMed

    Florine, Emily M; Miller, Rachel E; Liebesny, Paul H; Mroszczyk, Keri A; Lee, Richard T; Patwari, Parth; Grodzinsky, Alan J

    2015-02-01

    Heparin-binding insulin-like growth factor 1 (HB-IGF-1) is a fusion protein of IGF-1 with the HB domain of heparin-binding epidermal growth factor-like growth factor. A single dose of HB-IGF-1 has been shown to bind specifically to cartilage and to promote sustained upregulation of proteoglycan synthesis in cartilage explants. Achieving strong integration between native cartilage and tissue-engineered cartilage remains challenging. We hypothesize that if a growth factor delivered by the tissue engineering scaffold could stimulate enhanced matrix synthesis by both the cells within the scaffold and the adjacent native cartilage, integration could be enhanced. In this work, we investigated methods for adsorbing HB-IGF-1 to self-assembling peptide hydrogels to deliver the growth factor to encapsulated chondrocytes and cartilage explants cultured with growth factor-loaded hydrogels. We tested multiple methods for adsorbing HB-IGF-1 in self-assembling peptide hydrogels, including adsorption prior to peptide assembly, following peptide assembly, and with/without heparan sulfate (HS, a potential linker between peptide molecules and HB-IGF-1). We found that HB-IGF-1 and HS were retained in the peptide for all tested conditions. A subset of these conditions was then studied for their ability to stimulate increased matrix production by gel-encapsulated chondrocytes and by chondrocytes within adjacent native cartilage. Adsorbing HB-IGF-1 or IGF-1 prior to peptide assembly was found to stimulate increased sulfated glycosaminoglycan per DNA and hydroxyproline content of chondrocyte-seeded hydrogels compared with basal controls at day 10. Cartilage explants cultured adjacent to functionalized hydrogels had increased proteoglycan synthesis at day 10 when HB-IGF-1 was adsorbed, but not IGF-1. We conclude that delivery of HB-IGF-1 to focal defects in cartilage using self-assembling peptide hydrogels is a promising technique that could aid cartilage repair via enhanced matrix production and integration with native tissue.

  19. Cellular internalization mechanism and intracellular trafficking of filamentous M13 phages displaying a cell-penetrating transbody and TAT peptide.

    PubMed

    Kim, Aeyung; Shin, Tae-Hwan; Shin, Seung-Min; Pham, Chuong D; Choi, Dong-Ki; Kwon, Myung-Hee; Kim, Yong-Sung

    2012-01-01

    Cellular internalization of bacteriophage by surface-displayed cell penetrating peptides has been reported, though the underlying mechanism remains elusive. Here we describe in detail the internalization mechanism and intracellular trafficking and stability of filamentous M13 phages, the cellular entry of which is mediated by surface-displayed cell-penetrating light chain variable domain 3D8 VL transbody (3D8 VL-M13) or TAT peptide (TAT-M13). Recombinant 3D8 VL-M13 and TAT-M13 phages were efficiently internalized into living mammalian cells via physiologically relevant, energy-dependent endocytosis and were recovered from the cells in their infective form with the yield of 3D8 VL-M13 being higher (0.005 ≈ 0.01%) than that of TAT-M13 (0.001 ≈ 0.005%). Biochemical and genetic studies revealed that 3D8 VL-M13 was internalized principally by caveolae-mediated endocytosis via interaction with heparan sulfate proteoglycans as cell surface receptors, whereas TAT-M13 was internalized by clathrin- and caveolae-mediated endocytosis utilizing chondroitin sulfate proteoglycans as cell surface receptors, suggesting that phage internalization occurs by physiological endocytotic mechanism through specific cell surface receptors rather than non-specific transcytotic pathways. Internalized 3D8 VL-M13 phages routed to the cytosol and remained stable for more than 18 h without further trafficking to other subcellular compartments, whereas TAT-M13 phages routed to several subcellular compartments before being degraded in lysosomes even after 2 h of internalization. Our results suggest that the internalizing mechanism and intracellular trafficking of filamentous M13 bacteriophages largely follow the attributes of the displayed cell-penetrating moiety. Efficient internalization and cytosolic localization of 3D8 VL transbody-displayed phages will provide a useful tool for intracellular delivery of polar macromolecules such as proteins, peptides, and siRNAs.

  20. Cellular Internalization Mechanism and Intracellular Trafficking of Filamentous M13 Phages Displaying a Cell-Penetrating Transbody and TAT Peptide

    PubMed Central

    Shin, Seung-Min; Pham, Chuong D.; Choi, Dong-Ki; Kwon, Myung-Hee; Kim, Yong-Sung

    2012-01-01

    Cellular internalization of bacteriophage by surface-displayed cell penetrating peptides has been reported, though the underlying mechanism remains elusive. Here we describe in detail the internalization mechanism and intracellular trafficking and stability of filamentous M13 phages, the cellular entry of which is mediated by surface-displayed cell-penetrating light chain variable domain 3D8 VL transbody (3D8 VL-M13) or TAT peptide (TAT-M13). Recombinant 3D8 VL-M13 and TAT-M13 phages were efficiently internalized into living mammalian cells via physiologically relevant, energy-dependent endocytosis and were recovered from the cells in their infective form with the yield of 3D8 VL-M13 being higher (0.005∼0.01%) than that of TAT-M13 (0.001∼0.005%). Biochemical and genetic studies revealed that 3D8 VL-M13 was internalized principally by caveolae-mediated endocytosis via interaction with heparan sulfate proteoglycans as cell surface receptors, whereas TAT-M13 was internalized by clathrin- and caveolae-mediated endocytosis utilizing chondroitin sulfate proteoglycans as cell surface receptors, suggesting that phage internalization occurs by physiological endocytotic mechanism through specific cell surface receptors rather than non-specific transcytotic pathways. Internalized 3D8 VL-M13 phages routed to the cytosol and remained stable for more than 18 h without further trafficking to other subcellular compartments, whereas TAT-M13 phages routed to several subcellular compartments before being degraded in lysosomes even after 2 h of internalization. Our results suggest that the internalizing mechanism and intracellular trafficking of filamentous M13 bacteriophages largely follow the attributes of the displayed cell-penetrating moiety. Efficient internalization and cytosolic localization of 3D8 VL transbody-displayed phages will provide a useful tool for intracellular delivery of polar macromolecules such as proteins, peptides, and siRNAs. PMID:23251631

  1. The effect of nutritional status and myogenic satellite cell age on turkey satellite cell proliferation, differentiation, and expression of myogenic transcriptional regulatory factors and heparan sulfate proteoglycans syndecan-4 and glypican-1.

    PubMed

    Harthan, Laura B; McFarland, Douglas C; Velleman, Sandra G

    2014-01-01

    Posthatch satellite cell mitotic activity is a critical component of muscle development and growth. Satellite cells are myogenic stem cells that can be induced by nutrition to follow other cellular developmental pathways, and whose mitotic activity declines with age. The objective of the current study was to determine the effect of restricting protein synthesis on the proliferation and differentiation, expression of myogenic transcriptional regulatory factors myogenic determination factor 1, myogenin, and myogenic regulatory factor 4, and expression of the heparan sulfate proteoglycans syndecan-4 and glypican-1 in satellite cells isolated from 1-d-, 7-wk-, and 16-wk-old turkey pectoralis major muscle (1 d, 7 wk, and 16 wk cells, respectively) by using variable concentrations of Met and Cys. Four Met concentrations-30 (control), 7.5, 3, or 0 mg/L with 3.2 mg/L of Cys per 1 mg/L of Met-were used for culture of satellite cells to determine the effect of nutrition and age on satellite cell behavior during proliferation and differentiation. Proliferation was reduced by lower Met and Cys concentrations in all ages at 96 h of proliferation. Differentiation was increased in the 1 d Met-restricted cells, whereas the 7 wk cells treated with 3 mg/L of Met had decreased differentiation. Reduced Met and Cys levels from the control did not significantly affect the 16 wk cells at 72 h of differentiation. However, medium with no Met or Cys suppressed differentiation at all ages. The expression of myogenic determination factor 1, myogenin, myogenic regulatory factor 4, syndecan-4, and glypican-1 was differentially affected by age and Met or Cys treatment. These data demonstrate the age-specific manner in which turkey pectoralis major muscle satellite cells respond to nutritional availability and the importance of defining optimal nutrition to maximize satellite cell proliferation and differentiation for subsequent muscle mass accretion.

  2. Glypican Is a Modulator of Netrin-Mediated Axon Guidance

    PubMed Central

    Blanchette, Cassandra R.; Perrat, Paola N.; Thackeray, Andrea; Bénard, Claire Y.

    2015-01-01

    Netrin is a key axon guidance cue that orients axon growth during neural circuit formation. However, the mechanisms regulating netrin and its receptors in the extracellular milieu are largely unknown. Here we demonstrate that in Caenorhabditis elegans, LON-2/glypican, a heparan sulfate proteoglycan, modulates UNC-6/netrin signaling and may do this through interactions with the UNC-40/DCC receptor. We show that developing axons misorient in the absence of LON-2/glypican when the SLT-1/slit guidance pathway is compromised and that LON-2/glypican functions in both the attractive and repulsive UNC-6/netrin pathways. We find that the core LON-2/glypican protein, lacking its heparan sulfate chains, and secreted forms of LON-2/glypican are functional in axon guidance. We also find that LON-2/glypican functions from the epidermal substrate cells to guide axons, and we provide evidence that LON-2/glypican associates with UNC-40/DCC receptor–expressing cells. We propose that LON-2/glypican acts as a modulator of UNC-40/DCC-mediated guidance to fine-tune axonal responses to UNC-6/netrin signals during migration. PMID:26148345

  3. Amino acid sequence surrounding the chondroitin sulfate attachment site of thrombomodulin regulates chondroitin polymerization.

    PubMed

    Izumikawa, Tomomi; Kitagawa, Hiroshi

    2015-05-01

    Thrombomodulin (TM) is a cell-surface glycoprotein and a critical mediator of endothelial anticoagulant function. TM exists as both a chondroitin sulfate (CS) proteoglycan (PG) form and a non-PG form lacking a CS chain (α-TM); therefore, TM can be described as a part-time PG. Previously, we reported that α-TM bears an immature, truncated linkage tetrasaccharide structure (GlcAβ1-3Galβ1-3Galβ1-4Xyl). However, the biosynthetic mechanism to generate part-time PGs remains unclear. In this study, we used several mutants to demonstrate that the amino acid sequence surrounding the CS attachment site influences the efficiency of chondroitin polymerization. In particular, the presence of acidic residues surrounding the CS attachment site was indispensable for the elongation of CS. In addition, mutants defective in CS elongation did not exhibit anti-coagulant activity, as in the case with α-TM. Together, these data support a model for CS chain assembly in which specific core protein determinants are recognized by a key biosynthetic enzyme involved in chondroitin polymerization. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Differential expression of syndecan isoforms during mouse incisor amelogenesis.

    PubMed

    Muto, Taro; Miyoshi, Keiko; Munesue, Seiichi; Nakada, Hiroshi; Okayama, Minoru; Matsuo, Takashi; Noma, Takafumi

    2007-08-01

    Syndecans are transmembranous heparan sulfate proteoglycans (HSPGs) with covalently attached glycosaminoglycan side-chains located on the cell surface. The mammalian syndecan family is composed of four types of syndecans (syndecan-1 to -4). Syndecans interact with the intracellular cytoskeleton through the cytoplasmic domains of their core proteins and membrane proteins, extracellular enzymes, growth factors, and matrix components, through their heparan-sulfate chains, to regulate developmental processes.Here, as a first step to assess the possible roles of syndecan proteins in amelogenesis, we examined the expression patterns of all syndecan isoforms in continuously growing mouse incisors, in which we can overview major differentiation stages of amelogenesis at a glance. Understanding the expression domain of each syndecan isoform during specific developmental stages seems useful for investigating their physiological roles in amelogenesis. Immunohistochemical analysis of syndecan core proteins in the lower incisors from postnatal day 1 mice revealed spatially and temporally specific expression patterns, with syndecan-1 expressed in undifferentiated epithelial and mesenchymal cells, and syndecan-2, -3, and -4 in more differentiated cells. These findings suggest that each syndecan isoform functions distinctly during the amelogenesis of the incisors of mice.

  5. Antiangiogenic activity of semisynthetic biotechnological heparins: low-molecular-weight-sulfated Escherichia coli K5 polysaccharide derivatives as fibroblast growth factor antagonists.

    PubMed

    Presta, Marco; Oreste, Pasqua; Zoppetti, Giorgio; Belleri, Mirella; Tanghetti, Elena; Leali, Daria; Urbinati, Chiara; Bugatti, Antonella; Ronca, Roberto; Nicoli, Stefania; Moroni, Emanuela; Stabile, Helena; Camozzi, Maura; Hernandez, German Andrés; Mitola, Stefania; Dell'Era, Patrizia; Rusnati, Marco; Ribatti, Domenico

    2005-01-01

    Low-molecular-weight heparin (LMWH) exerts antitumor activity in clinical trials. The K5 polysaccharide from Escherichia coli has the same structure as the heparin precursor. Chemical and enzymatic modifications of K5 polysaccharide lead to the production of biotechnological heparin-like compounds. We investigated the fibroblast growth factor-2 (FGF2) antagonist and antiangiogenic activity of a series of LMW N,O-sulfated K5 derivatives. Surface plasmon resonance analysis showed that LMW-K5 derivatives bind FGF2, thus inhibiting its interaction with heparin immobilized to a BIAcore sensor chip. Interaction of FGF2 with tyrosine-kinase receptors (FGFRs), heparan sulfate proteoglycans (HSPGs), and alpha(v)beta3 integrin is required for biological response in endothelial cells. Similar to LMWH, LMW-K5 derivatives abrogate the formation of HSPG/FGF2/FGFR ternary complexes by preventing FGF2-mediated attachment of FGFR1-overexpressing cells to HSPG-bearing cells and inhibit FGF2-mediated endothelial cell proliferation. However, LMW-K5 derivatives, but not LMWH, also inhibit FGF2/alpha(v)beta3 integrin interaction and consequent FGF2-mediated endothelial cell sprouting in vitro and angiogenesis in vivo in the chick embryo chorioallantoic membrane. LMW N,O-sulfated K5 derivatives affect both HSPG/FGF2/FGFR and FGF2/alpha(v)beta3 interactions and are endowed with FGF2 antagonist and antiangiogenic activity. These compounds may provide the basis for the design of novel LMW heparin-like angiostatic compounds.

  6. Chondroitin 6-O-sulfotransferases are required for morphogenesis of the notochord in the ascidian embryo.

    PubMed

    Nakamura, Jun; Yoshida, Keita; Sasakura, Yasunori; Fujiwara, Shigeki

    2014-12-01

    Chondroitin sulfate (CS) is a sulfated polysaccharide chain that binds to various core proteins to form proteoglycans. The amount and position of sulfate groups in CS are variable among different tissues, and are determined by specific sulfotransferases. Although the ascidians are the closest relatives of vertebrates, the functions of their sulfotransferases have not been studied. The genome of the ascidian Ciona intestinalis contains eight genes encoding proteins similar to chondroitin 6-O-sulfotransferases (C6STs), which appear to have independently diverged in the ascidian lineage during evolution. Among them, Ci-C6ST-like1 and Ci-C6ST-like7 were predominantly expressed in the developing notochord. In addition, they were weakly expressed in the neural tube. The disruption of either one of them affected the convergent extension movement of notochordal cells. Presumptive notochord cells coming from both sides of the embryo did not intercalate. The results suggest that both of them are necessary. In some cases, the anterior neural tube failed to close. Forced expression of Ci-C6ST-like1 or Ci-C6ST-like7 in the notochord restored the normal intercalation of notochordal cells, indicating that the effects of morpholino oligos are specific. Ci-C6ST-like1 and Ci-C6ST-like7 are required for the morphogenesis of the notochord in the ascidian embryo. © 2014 Wiley Periodicals, Inc.

  7. LAR-RPTP Clustering Is Modulated by Competitive Binding between Synaptic Adhesion Partners and Heparan Sulfate

    PubMed Central

    Won, Seoung Youn; Kim, Cha Yeon; Kim, Doyoun; Ko, Jaewon; Um, Ji Won; Lee, Sung Bae; Buck, Matthias; Kim, Eunjoon; Heo, Won Do; Lee, Jie-Oh; Kim, Ho Min

    2017-01-01

    The leukocyte common antigen-related receptor protein tyrosine phosphatases (LAR-RPTPs) are cellular receptors of heparan sulfate (HS) and chondroitin sulfate (CS) proteoglycans that direct axonal growth and neuronal regeneration. LAR-RPTPs are also synaptic adhesion molecules that form trans-synaptic adhesion complexes by binding to various postsynaptic adhesion ligands, such as Slit- and Trk-like family of proteins (Slitrks), IL-1 receptor accessory protein-like 1 (IL1RAPL1), interleukin-1 receptor accessory protein (IL-1RAcP) and neurotrophin receptor tyrosine kinase C (TrkC), to regulate synaptogenesis. Here, we determined the crystal structure of the human LAR-RPTP/IL1RAPL1 complex and found that lateral interactions between neighboring LAR-RPTP/IL1RAPL1 complexes in crystal lattices are critical for the higher-order assembly and synaptogenic activity of these complexes. Moreover, we found that LAR-RPTP binding to the postsynaptic adhesion ligands, Slitrk3, IL1RAPL1 and IL-1RAcP, but not TrkC, induces reciprocal higher-order clustering of trans-synaptic adhesion complexes. Although LAR-RPTP clustering was induced by either HS or postsynaptic adhesion ligands, the dominant binding of HS to the LAR-RPTP was capable of dismantling pre-established LAR-RPTP-mediated trans-synaptic adhesion complexes. These findings collectively suggest that LAR-RPTP clustering for synaptogenesis is modulated by a complex synapse-organizing protein network. PMID:29081732

  8. Biosynthesis of small proteoglycan II (decorin) by chondrocytes and evidence for a procore protein.

    PubMed

    Sawhney, R S; Hering, T M; Sandell, L J

    1991-05-15

    We have studied the biosynthesis of cartilage dermatan sulfate proteoglycan II (DS-PGII) (decorin) using in vitro translation of mRNA to determine the size of the primary gene product and by radiolabeling the protein in the presence of tunicamycin to inhibit the addition of Asn-linked oligosaccharides. Pulse-chase experiments were performed to examine post-translational processing and secretion. Inhibitors of oligosaccharide processing were used to determine whether DS-PGII molecules containing partially processed oligosaccharides could become proteoglycans and be secreted. Cell-free translation of sucrose gradient-fractionated RNA and subsequent immunoprecipitation of the core protein confirmed that the functional translated mRNA is in the size range of the two mRNA species observed by hybridization of chondrocyte RNA with a bone PGII cloned probe and that the translation product is a single protein with an apparent molecular mass of 42 kDa. Digestion of the intact proteoglycan (average molecular mass = 103 kDa) with chondroitinase ABC or AC results in an approximately 48-49-kDa product. Chondrocytes treated with tunicamycin to inhibit Asn-linked oligosaccharide addition synthesize and secrete a glycosaminoglycan (GAG)-substituted proteoglycan (average molecular mass = 86 kDa), yielding a 42-kDa core protein after chondroitinase ABC digestion, showing that Asn-linked oligosaccharides are not required for the addition of GAG chains or secretion. Following a short pulse (10 min) of [3H]leucine, three glycosylated forms of the DS-PGII core protein were observed, one of which is likely to be the precursor form of PGII predicted by the implied protein sequence of both bovine and human cDNA clones. Following the apparent cleavage of the propeptide, GAG-substituted intracellular core protein is detectable. Susceptibility to endoglycosidase H indicates that approximately one-third of the secreted core protein contains exclusively complex-type Asn-linked oligosaccharides and approximately two-thirds contain high mannose as well as complex-type oligosaccharides. Secreted DS-PGII appears to be fully substituted with three Asn-linked oligosaccharide chains. Inhibitors of oligosaccharide processing, however, permitted secretion of GAG-substituted DS-PGII that was fully (three chains) or incompletely (one or two chains) substituted with partially processed Asn-linked carbohydrate chains. By comparison of chondrocyte DS-PGII with fibroblast DS-PGII, we conclude that the addition and processing of Asn-linked carbohydrate chains are directed by the amino acid sequence of the core protein. The results reported here also suggest that the addition of xylose, the initial step in GAG chain synthesis, occurs early in biosynthesis and is determined by the primary amino acid sequence of the core protein.(ABSTRACT TRUNCATED AT 400 WORDS)

  9. Analyses of chondrogenic induction of adipose mesenchymal stem cells by combined co-stimulation mediated by adenoviral gene transfer

    PubMed Central

    2013-01-01

    Introduction Adipose-derived stem cells (ASCs) have the potential to differentiate into cartilage under stimulation with some reported growth and transcriptional factors, which may constitute an alternative for cartilage replacement approaches. In this study, we analyzed the in vitro chondrogenesis of ASCs transduced with adenoviral vectors encoding insulin-like growth factor-1 (IGF-1), transforming growth factor beta-1 (TGF-β1), fibroblast growth factor-2 (FGF-2), and sex-determining region Y-box 9 (SOX9) either alone or in combinations. Methods Aggregate cultures of characterized ovine ASCs were transduced with 100 multiplicity of infections of Ad.IGF-1, Ad.TGF-β1, Ad.FGF-2, and Ad.SOX9 alone or in combination. These were harvested at various time points for detection of cartilage-specific genes expression by quantitative real-time PCR or after 14 and 28 days for histologic and biochemical analyses detecting proteoglycans, collagens (II, I and X), and total sulfated glycosaminoglycan and collagen content, respectively. Results Expression analyses showed that co-expression of IGF-1 and FGF-2 resulted in higher significant expression levels of aggrecan, biglycan, cartilage matrix, proteoglycan, and collagen II (all P ≤0.001 at 28 days). Aggregates co-transduced with Ad.IGF-1/Ad.FGF-2 showed a selective expression of proteoglycans and collagen II, with limited expression of collagens I and × demonstrated by histological analyses, and had significantly greater glycosaminoglycan and collagen production than the positive control (P ≤0.001). Western blot analyses for this combination also demonstrated increased expression of collagen II, while expression of collagens I and × was undetectable and limited, respectively. Conclusion Combined overexpression of IGF-1/FGF-2 within ASCs enhances their chondrogenic differentiation inducing the expression of chondrogenic markers, suggesting that this combination is more beneficial than the other factors tested for the development of cell-based therapies for cartilage repair. PMID:23899094

  10. Insights into the key roles of proteoglycans in breast cancer biology and translational medicine

    PubMed Central

    Theocharis, Achilleas D.; Skandalis, Spyros S.; Neill, Thomas; Multhaupt, Hinke A. B.; Hubo, Mario; Frey, Helena; Gopal, Sandeep; Gomes, Angélica; Afratis, Nikos; Lim, Hooi Ching; Couchman, John R.; Filmus, Jorge; Sanderson, Ralph D.; Schaefer, Liliana; Iozzo, Renato V.; Karamanos, Nikos K.

    2015-01-01

    Proteoglycans control numerous normal and pathological processes, among which are morphogenesis, tissue repair, inflammation, vascularization and cancer metastasis. During tumor development and growth, proteoglycan expression is markedly modified in the tumor microenvironment. Altered expression of proteoglycans on tumor and stromal cell membranes affects cancer cell signaling, growth and survival, cell adhesion, migration and angiogenesis. Despite the high complexity and heterogeneity of breast cancer, the rapid evolution in our knowledge that proteoglycans are among the key players in the breast tumor microenvironment suggests their potential as pharmacological targets in this type of cancer. It has been recently suggested that pharmacological treatment may target proteoglycan metabolism, their utilization as targets for immunotherapy or their direct use as therapeutic agents. The diversity inherent in the proteoglycans that will be presented herein provides the potential for multiple layers of regulation of breast tumor behavior. This review summarizes recent developments concerning the biology of selected proteoglycans in breast cancer, and presents potential targeted therapeutic approaches based on their novel key roles in breast cancer. PMID:25829250

  11. Acceptor Specificity of the Pasteurella Hyaluronan and Chondroitin Synthases and Production of Chimeric Glycosaminoglycans*†

    PubMed Central

    Tracy, Breca S.; Avci, Fikri Y.; Linhardt, Robert J.; DeAngelis, Paul L.

    2014-01-01

    The hyaluronan (HA) synthase, PmHAS, and the chondroitin synthase, PmCS, from the Gram-negative bacterium Pasteurella multocida polymerize the glycosaminoglycan (GAG) sugar chains HA or chondroitin, respectively. The recombinant Escherichia coli-derived enzymes were shown previously to elongate exogenously supplied oligosaccharides of their cognate GAG (e.g. HA elongated by PmHAS). Here we show that oligosaccharides and polysaccharides of certain noncognate GAGs (including sulfated and iduronic acid-containing forms) are elongated by PmHAS (e.g. chondroitin elongated by PmHAS) or PmCS. Various acceptors were tested in assays where the synthase extended the molecule with either a single monosaccharide or a long chain (~102–4 sugars). Certain GAGs were very poor acceptors in comparison to the cognate molecules, but elongated products were detected nonetheless. Overall, these findings suggest that for the interaction between the acceptor and the enzyme (a) the orientation of the hydroxyl at the C-4 position of the hexosamine is not critical, (b) the conformation of C-5 of the hexuronic acid (glucuronic versus iduronic) is not crucial, and (c) additional negative sulfate groups are well tolerated in certain cases, such as on C-6 of the hexosamine, but others, including C-4 sulfates, were not or were poorly tolerated. In vivo, the bacterial enzymes only process unsulfated polymers; thus it is not expected that the PmCS and PmHAS catalysts would exhibit such relative relaxed sugar specificity by acting on a variety of animal-derived sulfated or epimerized GAGs. However, this feature allows the chemoenzymatic synthesis of a variety of chimeric GAG polymers, including mimics of proteoglycan complexes. PMID:17099217

  12. Age-related impairment of endothelial progenitor cell migration correlates with structural alterations of heparan sulfate proteoglycans.

    PubMed

    Williamson, Kate A; Hamilton, Andrew; Reynolds, John A; Sipos, Peter; Crocker, Ian; Stringer, Sally E; Alexander, Yvonne M

    2013-02-01

    Aging poses one of the largest risk factors for the development of cardiovascular disease. The increased propensity toward vascular pathology with advancing age maybe explained, in part, by a reduction in the ability of circulating endothelial progenitor cells to contribute to vascular repair and regeneration. Although there is evidence to suggest that colony forming unit-Hill cells and circulating angiogenic cells are subject to age-associated changes that impair their function, the impact of aging on human outgrowth endothelial cell (OEC) function has been less studied. We demonstrate that OECs isolated from cord blood or peripheral blood samples from young and old individuals exhibit different characteristics in terms of their migratory capacity. In addition, age-related structural changes were discovered in OEC heparan sulfate (HS), a glycocalyx component that is essential in many signalling pathways. An age-associated decline in the migratory response of OECs toward a gradient of VEGF significantly correlated with a reduction in the relative percentage of the trisulfated disaccharide, 2-O-sulfated-uronic acid, N, 6-O-sulfated-glucosamine (UA[2S]-GlcNS[6S]), within OEC cell surface HS polysaccharide chains. Furthermore, disruption of cell surface HS reduced the migratory response of peripheral blood-derived OECs isolated from young subjects to levels similar to that observed for OECs from older individuals. Together these findings suggest that aging is associated with alterations in the fine structure of HS on the cell surface of OECs. Such changes may modulate the migration, homing, and engraftment capacity of these repair cells, thereby contributing to the progression of endothelial dysfunction and age-related vascular pathologies. © 2012 The Authors Aging Cell © 2012 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland.

  13. Gas-Phase Analysis of the Complex of Fibroblast GrowthFactor 1 with Heparan Sulfate: A Traveling Wave Ion Mobility Spectrometry (TWIMS) and Molecular Modeling Study

    NASA Astrophysics Data System (ADS)

    Zhao, Yuejie; Singh, Arunima; Xu, Yongmei; Zong, Chengli; Zhang, Fuming; Boons, Geert-Jan; Liu, Jian; Linhardt, Robert J.; Woods, Robert J.; Amster, I. Jonathan

    2017-01-01

    Fibroblast growth factors (FGFs) regulate several cellular developmental processes by interacting with cell surface heparan proteoglycans and transmembrane cell surface receptors (FGFR). The interaction of FGF with heparan sulfate (HS) is known to induce protein oligomerization, increase the affinity of FGF towards its receptor FGFR, promoting the formation of the HS-FGF-FGFR signaling complex. Although the role of HS in the signaling pathways is well recognized, the details of FGF oligomerization and formation of the ternary signaling complex are still not clear, with several conflicting models proposed in literature. Here, we examine the effect of size and sulfation pattern of HS upon FGF1 oligomerization, binding stoichiometry and conformational stability, through a combination of ion mobility (IM) and theoretical modeling approaches. Ion mobility-mass spectrometry (IMMS) of FGF1 in the presence of several HS fragments ranging from tetrasaccharide (dp4) to dodecasaccharide (dp12) in length was performed. A comparison of the binding stoichiometry of variably sulfated dp4 HS to FGF1 confirmed the significance of the previously known high-affinity binding motif in FGF1 dimerization, and demonstrated that certain tetrasaccharide-length fragments are also capable of inducing dimerization of FGF1. The degree of oligomerization was found to increase in the presence of dp12 HS, and a general lack of specificity for longer HS was observed. Additionally, collision cross-sections (CCSs) of several FGF1-HS complexes were calculated, and were found to be in close agreement with experimental results. Based on the (CCSs) a number of plausible binding modes of 2:1 and 3:1 FGF1-HS are proposed.

  14. A Novel Hyaluronidase from Brown Spider (Loxosceles intermedia) Venom (Dietrich's Hyaluronidase): From Cloning to Functional Characterization

    PubMed Central

    Ferrer, Valéria Pereira; de Mari, Thiago Lopes; Gremski, Luiza Helena; Trevisan Silva, Dilza; da Silveira, Rafael Bertoni; Gremski, Waldemiro; Chaim, Olga Meiri; Senff-Ribeiro, Andrea; Nader, Helena Bonciani; Veiga, Silvio Sanches

    2013-01-01

    Loxoscelism is the designation given to clinical symptoms evoked by Loxosceles spider's bites. Clinical manifestations include skin necrosis with gravitational spreading and systemic disturbs. The venom contains several enzymatic toxins. Herein, we describe the cloning, expression, refolding and biological evaluation of a novel brown spider protein characterized as a hyaluronidase. Employing a venom gland cDNA library, we cloned a hyaluronidase (1200 bp cDNA) that encodes for a signal peptide and a mature protein. Amino acid alignment revealed a structural relationship with members of hyaluronidase family, such as scorpion and snake species. Recombinant hyaluronidase was expressed as N-terminal His-tag fusion protein (∼45 kDa) in inclusion bodies and activity was achieved using refolding. Immunoblot analysis showed that antibodies that recognize the recombinant protein cross-reacted with hyaluronidase from whole venom as well as an anti-venom serum reacted with recombinant protein. Recombinant hyaluronidase was able to degrade purified hyaluronic acid (HA) and chondroitin sulfate (CS), while dermatan sulfate (DS) and heparan sulfate (HS) were not affected. Zymograph experiments resulted in ∼45 kDa lytic zones in hyaluronic acid (HA) and chondroitin sulfate (CS) substrates. Through in vivo experiments of dermonecrosis using rabbit skin, the recombinant hyaluronidase was shown to increase the dermonecrotic effect produced by recombinant dermonecrotic toxin from L. intermedia venom (LiRecDT1). These data support the hypothesis that hyaluronidase is a “spreading factor”. Recombinant hyaluronidase provides a useful tool for biotechnological ends. We propose the name Dietrich's Hyaluronidase for this enzyme, in honor of Professor Carl Peter von Dietrich, who dedicated his life to studying proteoglycans and glycosaminoglycans. PMID:23658852

  15. Structural studies reveal an important role for the pleiotrophin C-terminus in mediating interactions with chondroitin sulfate.

    PubMed

    Ryan, Eathen; Shen, Di; Wang, Xu

    2016-04-01

    Pleiotrophin (PTN) is a potent glycosaminoglycan-binding cytokine that is important in neural development, angiogenesis and tissue regeneration. Much of its activity is attributed to its interactions with the chondroitin sulfate (CS) proteoglycan, receptor type protein tyrosine phosphatase ζ (PTPRZ). However, there is little high resolution structural information on the interactions between PTN and CS, nor is it clear why the C-terminal tail of PTN is necessary for signaling through PTPRZ, even though it does not contribute to heparin binding. We determined the first structure of PTN and analyzed its interactions with CS. Our structure shows that PTN possesses large basic surfaces on both of its structured domains and also that residues in the hinge segment connecting the domains have significant contacts with the C-terminal domain. Our analysis of PTN-CS interactions showed that the C-terminal tail of PTN is essential for maintaining stable interactions with chondroitin sulfate A, the type of CS commonly found on PTPRZ. These results offer the first possible explanation of why truncated PTN missing the C-terminal tail is unable to signal through PTPRZ. NMR analysis of the interactions of PTN with CS revealed that the C-terminal domain and hinge of PTN make up the major CS-binding site in PTN, and that removal of the C-terminal tail weakened the affinity of the site for CSA but not for other high sulfation density CS. Coordinates of the ensemble of ten PTN structures have been deposited in RCSB under accession number 2n6f. Chemical shifts assignments and structural constraints have been deposited in BMRB under accession number 25762. © 2016 Federation of European Biochemical Societies.

  16. Drosophila glypicans Dally and Dally-like are essential regulators for JAK/STAT signaling and Unpaired distribution in eye development

    PubMed Central

    Zhang, Yan; You, Jia; Ren, Wenyan; Lin, Xinhua

    2013-01-01

    The highly conserved janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway is a well-known signaling system that is involved in many biological processes. In Drosophila, this signaling cascade is activated by ligands of the Unpaired (Upd) family. Therefore, the regulation of Upd distribution is one of the key issues in controlling the JAK/STAT signaling activity and function. Heparan sulfate proteoglycans (HSPGs) are macromolecules that regulate the distribution of many ligand proteins including Wingless, Hedgehog and Decapentaplegic (Dpp). Here we show that during Drosophila eye development, HSPGs are also required in normal Upd distribution and JAK/STAT signaling activity. Loss of HSPG biosynthesis enzyme Brother of tout-velu (Botv), Sulfateless (Sfl), or glypicans Division abnormally delayed (Dally) and Dally-like protein (Dlp) led to reduced levels of extracellular Upd and reduction in JAK/STAT signaling activity. Overexpression of dally resulted in the accumulation of Upd and up-regulation of the signaling activity. Luciferase assay also showed that Dally promotes JAK/STAT signaling activity, and is dependent on its heparin sulfate chains. These data suggest that Dally and Dlp are essential for Upd distribution and JAK/STAT signaling activity. PMID:23313126

  17. Replacement of proteoglycans in embryonic chick cartilage in organ culture after treatment with testicular hyaluronidase

    PubMed Central

    Hardingham, T. E.; Fitton-Jackson, Sylvia; Muir, Helen

    1972-01-01

    Explants of cartilage from tibiae of 11–12 days chick embryos were grown in organ culture. To one group hyaluronidase was added to the medium during the first 2 days of culture; the treated tissue was then cultured in medium without enzyme for a further 4 days. Control explants grown in hyaluronidase-free medium for 6 days grew rapidly in size and the total hexosamine content more than doubled during this time. After exposure to hyaluronidase, much of the hexosamine was lost from treated cartilage and appeared in the culture medium, but it was mostly replaced in the tissue during the subsequent recovery period. Analysis of cartilage and medium showed that net synthesis of hexosamine increased greatly in treated cartilage. The proteoglycans were extracted by two procedures from control and treated cartilage after 2, 4 and 6 days in culture. The hydrodynamic sizes of the purified proteoglycans were compared by gel chromatography and the composition of the gel-chromatographic fractions was determined. The proteoglycans from controls did not change during culture, but after exposure to hyaluronidase the proteoglycans from treated cartilage were of much smaller size and lower chondroitin sulphate content. During recovery, even though new proteoglycans were formed, they were nevertheless of smaller size and lower chondroitin sulphate content than control proteoglycans. They gradually became more like control proteoglycans during recovery from treatment, but even after 4 days they were not yet the same. After 2 days of treatment with the enzyme, the chondroitin sulphate in the cartilage was of shorter chain length than in controls but during recovery after 4 and 6 days in culture, the chain lengths in control and treated cartilage were similar. It is concluded that the proteoglycans formed in embryo cartilage in response to their depletion by enzyme treatment contained fewer chondroitin sulphate chains attached to the protein moiety of proteoglycans. This may have resulted from a failure under stress to glycosylate the protein moiety to the usual extent; alternatively the synthesis of normal proteoglycans of low chondroitin sulphate content may have increased, thus changing the proteoglycan population. PMID:4265022

  18. Assessment of Heparanase-Mediated Angiogenesis Using Microvascular Endothelial Cells: Identification of λ-Carrageenan Derivative as a Potent Anti Angiogenic Agent.

    PubMed

    Poupard, Nicolas; Badarou, Pamela; Fasani, Fabienne; Groult, Hugo; Bridiau, Nicolas; Sannier, Frédéric; Bordenave-Juchereau, Stéphanie; Kieda, Claudine; Piot, Jean-Marie; Grillon, Catherine; Fruitier-Arnaudin, Ingrid; Maugard, Thierry

    2017-05-09

    Heparanase is overexpressed by tumor cells and degrades the extracellular matrix proteoglycans through cleavage of heparan sulfates (HS), allowing pro-angiogenic factor release and thus playing a key role in tumor angiogenesis and metastasis. Here we propose new HS analogs as potent heparanase inhibitors: Heparin as a positive control, Dextran Sulfate, λ-Carrageenan, and modified forms of them obtained by depolymerization associated to glycol splitting (RD-GS). After heparanase activity assessment, 11 kDa RD-GS-λ-Carrageenan emerged as the most effective heparanase inhibitor with an IC 50 of 7.32 ng/mL compared to 10.7 ng/mL for the 16 kDa unfractionated heparin. The fractionated polysaccharides were then tested in a heparanase-rich medium-based in vitro model, mimicking tumor microenvironment, to determine their effect on microvascular endothelial cells (HSkMEC) angiogenesis. As a preliminary study, we identified that under hypoxic and nutrient poor conditions, MCF-7 cancer cells released much more mature heparanase in their supernatant than in normal conditions. Then a Matrigel TM assay using HSkMEC cultured under hypoxic conditions in the presence (or not) of this heparanase-rich supernatant was realized. Adding heparanase-rich media strongly enhanced angiogenic network formation with a production of twice more pseudo-vessels than with the control. When sulfated polysaccharides were tested in this angiogenesis assay, RD-GS-λ-Carrageenan was identified as a promising anti-angiogenic agent.

  19. Analysis of oversulfation in biglycan chondroitin/dermatan sulfate oligosaccharides by chip-based nanoelectrospray ionization multistage mass spectrometry.

    PubMed

    Flangea, Corina; Sisu, Eugen; Seidler, Daniela G; Zamfir, Alina D

    2012-01-15

    Biglycan (BGN) is a small proteoglycan that consists of a protein core containing leucine-rich repeat regions and two glycosaminoglycan (GAG) chains of either chondroitin sulfate (CS) or dermatan sulfate (DS) type. The development of novel, highly efficient analytical methods for structural identification of BGN-derived CS/DS motifs, possibly implicated in biological events, is currently the focus of research. In this work, an improved analytical method based on fully automated chip-nanoelectrospray ionization (nanoESI) in conjunction with high-capacity ion trap (HCT) multistage mass spectrometry (MS) by collision-induced dissociation (CID) was for the first time applied to BGN CS/DS oligosaccharide analysis. The CS/DS chains were released from transfected 293 BGN by β-elimination. The chain was digested with AC I lyase, and the resulting mixture was purified and subsequently separated by size exclusion chromatography (SEC). Di- and tetrasaccharide fractions were pooled and characterized in detail using the developed chip-nanoESI protocol. The chip-nanoESI MS profile in the negative ion mode revealed the presence of under-, regularly, and oversulfated species in both di- and tetrasaccharide fractions. CID MS(2)-MS(3) yielded sequence patterns consistent with unusual oversulfated 4,5-Δ-GlcA(2S)-GalNAc(4S) and 4,5-Δ-GlcA(2S)-GalNAc(6S)-IdoA(2S)-GalNAc(6S) motifs. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. The in vitro interactions between serum lipoproteins and proteoglycans of the neointima of rabbit aorta after a single balloon catheter injury.

    PubMed

    Alavi, M Z; Richardson, M; Moore, S

    1989-02-01

    The effect of injury-induced alterations in the aortic neointimal proteoglycans on their binding with homologous serum lipoproteins was examined. Proteoglycans of the aortic intimal-medial tissues of rabbits that had undergone denudation with a balloon catheter 12 weeks earlier were isolated after homogenization of the tissues in 0.33 M sucrose, ultracentrifugation and subsequently by gel-exclusion chromatography. Lipoproteins from the plasma of healthy donors were prepared by sequential, ultracentrifugal floatation after density adjustment with KBr. To study the interactions, aliquots of electrophoretically pure very low-density lipoproteins (VLDL, d less than 1.006 g/ml), low-density lipoproteins (LDL, d = 1.019-1.063 g/ml), or high-density lipoproteins (HDL, d = 1.210 g/ml) were incubated with proteoglycans in the presence of Ca++ and Mg++ at 4 C. The amount of cholesterol found in the resulting pellet was measured as a marker of the binding capacity of the proteoglycans. Among lipoprotein fractions both VLDL and LDL showed strong binding with proteoglycans, whereas no appreciable binding was observed when incubation experiments were done with HDL. There were significant differences in the lipoprotein binding capacity of proteoglycan of control and injured animals, indicating that injury induced changes in proteoglycan composition exert profound influences on their ionic interactions.

  1. An ultrastructural and immunogold localization study of proteoglycans associated with the osteocytes of fetal bone in osteogenesis imperfecta.

    PubMed

    Sarathchandra, P; Pope, F M; Ali, S Y

    1996-06-01

    Osteogenesis imperfecta (OI) is a rare, heterogeneous, inherited connective tissue disorder frequently caused by abnormalities of type I collagen. It is characterized by bone fragility, osteopenia, and progressive skeletal deformities. Electron microscopy of three OI type II fetal bone samples revealed numerous large osteocyte lacunae. In addition, there was a perilacunar osteoid-like band of collagen surrounding the osteocytes, which was unmineralized and morphologically unusual. Furthermore, large osteocyte lacunae contained fine particles and filamentous material similar to the expected ultrastructural appearance of proteoglycans. More detailed examination was carried out using histochemical and immunogold localization of proteoglycans at light and ultrastructural levels. These tests and the use of electron probe X-ray microanalysis confirmed that the material in the osteocyte lacunae was proteoglycan. In contrast, in the age- and site-matched normal fetal bone, all the osteocyte lacunae appeared negative for proteoglycan. Proteoglycans are regarded as inhibitors of calcification. Our observation of substantial amounts of proteoglycan in abnormally enlarged osteocytic lacunae of some OI fetal bone suggests association with the abnormal bone of this particular subtype of OI type II.

  2. Independent modulation of collagen fibrillogenesis by decorin and lumican.

    PubMed

    Neame, P J; Kay, C J; McQuillan, D J; Beales, M P; Hassell, J R

    2000-05-01

    The leucine-rich proteoglycans (also known as "small, leucine-rich proteoglycans," or SLRPs) lumican and decorin are thought to be involved in the regulation of collagen fibril assembly. Preparation of these proteoglycans in chemical amounts without exposure to denaturants has recently been achieved by infecting HT-1080 cells with vaccinia virus that contains an expression cassette for these molecules. Addition of lumican and decorin to a collagen fibrillogenesis assay based on turbidity demonstrated that lumican accelerated initial fibril formation while decorin retarded initial fibril formation. At the end of fibrillogenesis, both proteoglycans resulted in an overall reduced turbidity, suggesting that fibril diameter was lower. The presence of both proteoglycans had a synergistic effect, retarding fibril formation to a greater degree than either proteoglycan individually. Competitive binding studies showed that lumican did not compete for decorin-binding sites on collagen fibrils. Both proteoglycans increased the stability of fibrils to thermal denaturation to approximately the same degree. These studies show that lumican does not compete for decorin-binding sites on collagen, that decorin and lumican modulate collagen fibrillogenesis, and that, in the process, they also enhance collagen fibril stability.

  3. Analysis of the intermediate size proteoglycans from the developing chick limb buds.

    PubMed

    Vasan, N

    1982-08-01

    Limb-bud proteoglycans are heterogeneous molecules which vary in their chemical and physical properties with development. This report describes proteoglycan intermediates (PG-I) that predominate in stage-34 limbs, and compares them with proteoglycan aggregates (PG-A) in stage-38 limbs. We analysed proteoglycans and their components extracted with guanidinium chloride by subjecting them to density gradient centrifugation, molecular sieve chromatography, electrophoretic separation, and selective enzymatic degradation. PG-I and PG-A have similar chondroitin sulphate composition, amino sugars, chondroitin sulphate side-chain length, glycoprotein link factors, and hyaluronic acid binding capacity, and both cross react with antisera prepared against cartilage-specific chick sternal proteoglycans. However, PG-I has lower molecular weight, lower buoyant density, and fewer chondroitin sulphate side chains on the protein core. The PG-I in the developing limb can be considered a mixture of smaller aggregates and cartilage-specific large monomers in which the former predominate.

  4. Transcriptome Profiling and Molecular Pathway Analysis of Genes in Association with Salinity Adaptation in Nile Tilapia Oreochromis niloticus

    PubMed Central

    Xu, Zhixin; Gan, Lei; Li, Tongyu; Xu, Chang; Chen, Ke; Wang, Xiaodan; Qin, Jian G.; Chen, Liqiao; Li, Erchao

    2015-01-01

    Nile tilapia Oreochromis niloticus is a freshwater fish but can tolerate a wide range of salinities. The mechanism of salinity adaptation at the molecular level was studied using RNA-Seq to explore the molecular pathways in fish exposed to 0, 8, or 16 (practical salinity unit, psu). Based on the change of gene expressions, the differential genes unions from freshwater to saline water were classified into three categories. In the constant change category (1), steroid biosynthesis, steroid hormone biosynthesis, fat digestion and absorption, complement and coagulation cascades were significantly affected by salinity indicating the pivotal roles of sterol-related pathways in response to salinity stress. In the change-then-stable category (2), ribosomes, oxidative phosphorylation, signaling pathways for peroxisome proliferator activated receptors, and fat digestion and absorption changed significantly with increasing salinity, showing sensitivity to salinity variation in the environment and a responding threshold to salinity change. In the stable-then-change category (3), protein export, protein processing in endoplasmic reticulum, tight junction, thyroid hormone synthesis, antigen processing and presentation, glycolysis/gluconeogenesis and glycosaminoglycan biosynthesis—keratan sulfate were the significantly changed pathways, suggesting that these pathways were less sensitive to salinity variation. This study reveals fundamental mechanism of the molecular response to salinity adaptation in O. niloticus, and provides a general guidance to understand saline acclimation in O. niloticus. PMID:26305564

  5. Immunophenotypes of macular corneal dystrophy in India and correlation with mutations in CHST6

    PubMed Central

    Klintworth, Gordon K.; Thonar, Eugene J-M.A.; Vemuganti, Geeta K.; Kannabiran, Chitra

    2009-01-01

    Purpose To determine the immunophenotypes of macular corneal dystrophy (MCD) in Indian patients and to correlate them with mutations in the carbohydrate 6-sulfotransferase (CHST6) gene. Methods Sixty-four patients from 53 families with MCD that were previously screened for mutations in CHST6 were included in an immunophenotype analysis. Antigenic keratan sulfate (AgKS) in serum as well as corneal tissue was evaluated in 31 families. Only cornea was evaluated in 11 families, and only serum was evaluated in 11 families. AgKS was detected in formalin-fixed, paraffin-embedded corneal sections by immunohistochemistry and in serum by ELISA using a monoclonal antibody against sulfated forms of KS in patients with MCD as well as normal controls. Results Analysis of corneal and/or serum AgKS disclosed MCD type I (27 families), MCD type IA (5 families), and MCD type II (3 families) in the cases studied. An additional 10 families were either MCD type I or MCD type IA since only serum AgKS data were available. Seven families manifested atypical immunophenotypes since the corneal AgKS expression was either of MCD type I or MCD type IA, but serum AgKS levels ranged from 19 ng/ml to 388 ng/ml. More than one immunophenotype was detected amongst siblings in two families. Each immunophenotype was associated with mutational heterogeneity in CHST6. Conclusions MCD type I was the predominant immunophenotype in the Indian population studied followed by MCD type IA and then MCD type II. We detected further immunophenotypic heterogeneity by finding atypical patterns of AgKS reactivity in a subset of families. There were no simple correlations between immunophenotypes and specific mutations in CHST6, suggesting that factors other than CHST6 mutations may be contributing to the immunophenotypes in MCD. PMID:19204788

  6. The Identification of Proteoglycans and Glycosaminoglycans in Archaeological Human Bones and Teeth

    PubMed Central

    Coulson-Thomas, Yvette M.; Coulson-Thomas, Vivien J.; Norton, Andrew L.; Gesteira, Tarsis F.; Cavalheiro, Renan P.; Meneghetti, Maria Cecília Z.; Martins, João R.; Dixon, Ronald A.; Nader, Helena B.

    2015-01-01

    Bone tissue is mineralized dense connective tissue consisting mainly of a mineral component (hydroxyapatite) and an organic matrix comprised of collagens, non-collagenous proteins and proteoglycans (PGs). Extracellular matrix proteins and PGs bind tightly to hydroxyapatite which would protect these molecules from the destructive effects of temperature and chemical agents after death. DNA and proteins have been successfully extracted from archaeological skeletons from which valuable information has been obtained; however, to date neither PGs nor glycosaminoglycan (GAG) chains have been studied in archaeological skeletons. PGs and GAGs play a major role in bone morphogenesis, homeostasis and degenerative bone disease. The ability to isolate and characterize PG and GAG content from archaeological skeletons would unveil valuable paleontological information. We therefore optimized methods for the extraction of both PGs and GAGs from archaeological human skeletons. PGs and GAGs were successfully extracted from both archaeological human bones and teeth, and characterized by their electrophoretic mobility in agarose gel, degradation by specific enzymes and HPLC. The GAG populations isolated were chondroitin sulfate (CS) and hyaluronic acid (HA). In addition, a CSPG was detected. The localization of CS, HA, three small leucine rich PGs (biglycan, decorin and fibromodulin) and glypican was analyzed in archaeological human bone slices. Staining patterns were different for juvenile and adult bones, whilst adolescent bones had a similar staining pattern to adult bones. The finding that significant quantities of PGs and GAGs persist in archaeological bones and teeth opens novel venues for the field of Paleontology. PMID:26107959

  7. Targeting of adhesion molecules as a therapeutic strategy in multiple myeloma.

    PubMed

    Neri, Paola; Bahlis, Nizar J

    2012-09-01

    Multiple myeloma (MM) is a clonal disorder of plasma cells that remains, for the most part, incurable despite the advent of several novel therapeutic agents. Tumor cells in this disease are cradled within the bone marrow (BM) microenvironment by an array of adhesive interactions between the BM cellular residents, the surrounding extracellular matrix (ECM) components such as fibronectin (FN), laminin, vascular cell adhesion molecule-1 (VCAM-1), proteoglycans, collagens and hyaluronan, and a variety of adhesion molecules on the surface of MM cells including integrins, hyaluronan receptors (CD44 and RHAMM) and heparan sulfate proteoglycans. Several signaling responses are activated by these interactions, affecting the survival, proliferation and migration of MM cells. An important consequence of these direct adhesive interactions between the BM/ECM and MM cells is the development of drug resistance. This phenomenon is termed "cell adhesion-mediated drug resistance" (CAM-DR) and it is thought to be one of the major mechanisms by which MM cells escape the cytotoxic effects of therapeutic agents. This review will focus on the adhesion molecules involved in the cross-talk between MM cells and components of the BM microenvironment. The complex signaling networks downstream of these adhesive molecules mediated by direct ligand binding or inside-out soluble factors signaling will also be reviewed. Finally, novel therapeutic strategies targeting these molecules will be discussed. Identification of the mediators of MM-BM interaction is essential to understand MM biology and to elucidate novel therapeutic targets for this disease.

  8. Decorin content and near infrared spectroscopy analysis of dried collagenous biomaterial samples.

    PubMed

    Aldema-Ramos, Mila L; Castell, Joan Carles; Muir, Zerlina E; Adzet, Jose Maria; Sabe, Rosa; Schreyer, Suzanne

    2012-12-14

    The efficient removal of proteoglycans, such as decorin, from the hide when processing it to leather by traditional means is generally acceptable and beneficial for leather quality, especially for softness and flexibility. A patented waterless or acetone dehydration method that can generate a product similar to leather called Dried Collagenous Biomaterial (known as BCD) was developed but has no effect on decorin removal efficiency. The Alcian Blue colorimetric technique was used to assay the sulfated glycosaminoglycan (sGAG) portion of decorin. The corresponding residual decorin content was correlated to the mechanical properties of the BCD samples and was comparable to the control leather made traditionally. The waterless dehydration and instantaneous chrome tanning process is a good eco-friendly alternative to transforming hides to leather because no additional effects were observed after examination using NIR spectroscopy and additional chemometric analysis.

  9. Dwarfism and age-associated spinal degeneration of heterozygote cmd mice defective in aggrecan

    PubMed Central

    Watanabe, Hideto; Nakata, Ken; Kimata, Koji; Nakanishi, Isao; Yamada, Yoshihiko

    1997-01-01

    Mouse cartilage matrix deficiency (cmd) is an autosomal recessive disorder caused by a genetic defect of aggrecan, a large chondroitin sulfate proteoglycan in cartilage. The homozygotes (−/−) are characterized by cleft palate and short limbs, tail, and snout. They die just after birth because of respiratory failure, and the heterozygotes (+/−) appear normal at birth. Here we report that the heterozygotes show dwarfism and develop spinal misalignment with age. Within 19 months of age, they exhibit spastic gait caused by misalignment of the cervical spine and die because of starvation. Histological examination revealed a high incidence of herniation and degeneration of vertebral discs. Electron microscopy showed a degeneration of disc chondrocytes in the heterozygotes. These findings may facilitate the identification of mutations in humans predisposed to spinal degeneration. PMID:9192671

  10. Regulation of Hedgehog Signalling Inside and Outside the Cell

    PubMed Central

    Ramsbottom, Simon A.; Pownall, Mary E.

    2016-01-01

    The hedgehog (Hh) signalling pathway is conserved throughout metazoans and plays an important regulatory role in both embryonic development and adult homeostasis. Many levels of regulation exist that control the release, reception, and interpretation of the hedgehog signal. The fatty nature of the Shh ligand means that it tends to associate tightly with the cell membrane, and yet it is known to act as a morphogen that diffuses to elicit pattern formation. Heparan sulfate proteoglycans (HSPGs) play a major role in the regulation of Hh distribution outside the cell. Inside the cell, the primary cilium provides an important hub for processing the Hh signal in vertebrates. This review will summarise the current understanding of how the Hh pathway is regulated from ligand production, release, and diffusion, through to signal reception and intracellular transduction. PMID:27547735

  11. Functional conservation of the human EXT1 tumor suppressor gene and its Drosophila homolog tout velu.

    PubMed

    Dasgupta, Ujjaini; Dixit, Bharat L; Rusch, Melissa; Selleck, Scott; The, Inge

    2007-08-01

    Heparan sulfate proteoglycans play a vital role in signaling of various growth factors in both Drosophila and vertebrates. In Drosophila, mutations in the tout velu (ttv) gene, a homolog of the mammalian EXT1 tumor suppressor gene, leads to abrogation of glycosaminoglycan (GAG) biosynthesis. This impairs distribution and signaling activities of various morphogens such as Hedgehog (Hh), Wingless (Wg), and Decapentaplegic (Dpp). Mutations in members of the exostosin (EXT) gene family lead to hereditary multiple exostosis in humans leading to bone outgrowths and tumors. In this study, we provide genetic and biochemical evidence that the human EXT1 (hEXT1) gene is conserved through species and can functionally complement the ttv mutation in Drosophila. The hEXT1 gene was able to rescue a ttv null mutant to adulthood and restore GAG biosynthesis.

  12. A multicenter, randomized, double-blind, dose-finding study of condoliase in patients with lumbar disc herniation.

    PubMed

    Matsuyama, Yukihiro; Chiba, Kazuhiro; Iwata, Hisashi; Seo, Takayuki; Toyama, Yoshiaki

    2018-05-01

    OBJECTIVE Chemonucleolysis with condoliase has the potential to be a new, less invasive therapeutic option for patients with lumbar disc herniation (LDH). The aim of the present study was to determine the most suitable therapeutic dose of condoliase. METHODS Patients between 20 and 70 years of age with unilateral leg pain, positive findings on the straight leg raise test, and LDH were recruited. All eligible patients were randomly assigned to receive condoliase (1.25, 2.5, or 5 U) or placebo. The primary end point was a change in the worst leg pain from preadministration (baseline) to week 13. The secondary end points were changes from baseline in the following items: worst back pain, Oswestry Disability Index (ODI), SF-36, and neurological examination. For pharmacokinetic and pharmacodynamic analyses, plasma condoliase concentrations and serum keratan sulfate concentrations were measured. The safety end points were adverse events (AEs) and radiographic and MRI parameters. Data on leg pain, back pain, abnormal neurological findings, and imaging parameters were collected until week 52. RESULTS A total of 194 patients received an injection of condoliase or placebo. The mean change in worst leg pain from baseline to week 13 was -31.7 mm (placebo), -46.7 mm (1.25 U), -41.1 mm (2.5 U), and -47.6 mm (5 U). The differences were significant at week 13 in the 1.25-U group (-14.9 mm; 95% CI -28.4 to -1.4 mm; p = 0.03) and 5-U group (-15.9 mm; 95% CI -29.0 to -2.7 mm; p = 0.01) compared with the placebo group. The dose-response improvement in the worst leg pain at week 13 was not significant (p = 0.14). The decrease in the worst leg pain in all 3 condoliase groups was observed from week 1 through week 52. Regarding the other end points, the worst back pain and results of the straight leg raise test, ODI, and SF-36 showed a tendency for sustained improvement in each of the condoliase groups until week 52. In all patients at all time points, plasma condoliase concentrations were below the detectable limit (< 100 μU/ml). Serum keratan sulfate concentrations significantly increased from baseline to 6 hours and 6 weeks after administration in all 3 condoliase groups. No patient died or developed anaphylaxis or neurological sequelae. Five serious AEs occurred in 5 patients (3 patients in the condoliase groups and 2 patients in the placebo group), resolved, and were considered unrelated to the investigational drug. Severe AEs occurred in 10 patients in the condoliase groups and resolved or improved. In the condoliase groups, back pain was the most frequent AE. Modic type 1 change and decrease in disc height were frequent imaging findings. Dose-response relationships were observed for the incidence of adverse drug reactions and decrease in disc height. CONCLUSIONS Condoliase significantly improved clinical symptoms in patients with LDH and was well tolerated. While all 3 doses had similar efficacy, the incidence of adverse drug reactions and decrease in disc height were dose dependent, thereby suggesting that 1.25 U would be the recommended clinical dose of condoliase. Clinical trial registration no.: NCT00634946 (clinicaltrials.gov).

  13. Effects of oxygen toxicity on cuprolinic blue-stained proteoglycans in alveolar basement membranes.

    PubMed

    Ferrara, T B; Fox, R B

    1992-02-01

    Effects of oxygen toxicity on distribution and density of proteoglycans in basement membranes of newborn rat lungs were assessed by electron microscopic analysis of tissues processed with cuprolinic blue, a cationic label that characteristically labels these anionically charged macromolecules. Newborn rats placed in greater than 95% oxygen at birth were killed at weekly intervals for 4 wk, and lung tissues fixed in 2.5% glutaraldehyde with 0.2% cuprolinic blue were processed for electron microscopy. Alveolar basement membranes from oxygen-treated and control animals were compared for differences in thickness and proteoglycan concentration and distribution. Results showed progressive thickening of alveolar basement membranes with increased duration of oxygen exposure. The normal distribution of proteoglycans, which is predominantly in the lamina rara externa of alveolar basement membranes, was frequently lost in thickened membranes found in oxygen-treated animals. Density of proteoglycans in these membranes decreased to 56% of normal by 2 wk of age and remained low with continued oxygen administration. Proteoglycan concentration in basement membranes on the interstitial side of alveolar capillaries in both control and oxygen-treated animals was low compared with proteoglycan concentration in basement membranes that opposed the alveolar air space, and administration of oxygen diminished these differences. These results demonstrate a direct alteration of proteoglycan distribution and density in the developing lung as a result of oxygen toxicity. This could result in decreased cell adhesion, influence the cellular response to lung injury, and contribute to the increased permeability seen with this disorder.

  14. Gravidity-Dependent Production of Antibodies That Inhibit Binding of Plasmodium falciparum-Infected Erythrocytes to Placental Chondroitin Sulfate Proteoglycan during Pregnancy

    PubMed Central

    O'Neil-Dunne, Iona; Achur, Rajeshwara N.; Agbor-Enoh, Sean T.; Valiyaveettil, Manojkumar; Naik, Ramachandra S.; Ockenhouse, Christian F.; Zhou, Ainong; Megnekou, Rosette; Leke, Rose; Taylor, Diane W.; Gowda, D. Channe

    2001-01-01

    During pregnancy, Plasmodium falciparum-infected erythrocytes sequester in the placenta by adhering to chondroitin 4-sulfate, creating a risk factor for both the mother and the fetus. The primigravidae are at higher risk for placental malaria than the multigravidae. This difference in susceptibility has been attributed to the lack of antibodies that block the adhesion of infected erythrocytes to placental chondroitin 4-sulfate in primigravid women. However, recent results show that many primigravidae at term have antibody levels similar to those of multigravidae, and thus the significance of antiadhesion antibodies in providing protection against malaria during pregnancy remains unclear. In this study, we analyzed plasma samples from women of various gravidities at different gestational stages for antiadhesion antibodies. The majority of women, regardless of gravidity, had similar levels of antibodies at term. Most primigravidae had low levels of or no antiadhesion antibodies prior to ∼20 weeks of pregnancy and then produced antibodies. Multigravidae also lacked antibodies until ∼12 weeks of pregnancy, but thereafter they efficiently produced antibodies. In pregnant women who had placental infection at term, higher levels of antiadhesion antibodies correlated with lower levels of placental parasitemia. The difference in kinetics of antibody production between primigravidae and multigravidae correlated with the prevalence of malaria in these groups, suggesting that antibodies are produced during pregnancy in response to placental infection. The early onset of efficient antibody response in multigravidae and the delayed production to antibodies in primigravidae appear to account for the gravidity-dependent differential susceptibilities of pregnant women to placental malaria. PMID:11705924

  15. Gravidity-dependent production of antibodies that inhibit binding of Plasmodium falciparum-infected erythrocytes to placental chondroitin sulfate proteoglycan during pregnancy.

    PubMed

    O'Neil-Dunne, I; Achur, R N; Agbor-Enoh, S T; Valiyaveettil, M; Naik, R S; Ockenhouse, C F; Zhou, A; Megnekou, R; Leke, R; Taylor, D W; Gowda, D C

    2001-12-01

    During pregnancy, Plasmodium falciparum-infected erythrocytes sequester in the placenta by adhering to chondroitin 4-sulfate, creating a risk factor for both the mother and the fetus. The primigravidae are at higher risk for placental malaria than the multigravidae. This difference in susceptibility has been attributed to the lack of antibodies that block the adhesion of infected erythrocytes to placental chondroitin 4-sulfate in primigravid women. However, recent results show that many primigravidae at term have antibody levels similar to those of multigravidae, and thus the significance of antiadhesion antibodies in providing protection against malaria during pregnancy remains unclear. In this study, we analyzed plasma samples from women of various gravidities at different gestational stages for antiadhesion antibodies. The majority of women, regardless of gravidity, had similar levels of antibodies at term. Most primigravidae had low levels of or no antiadhesion antibodies prior to ~20 weeks of pregnancy and then produced antibodies. Multigravidae also lacked antibodies until ~12 weeks of pregnancy, but thereafter they efficiently produced antibodies. In pregnant women who had placental infection at term, higher levels of antiadhesion antibodies correlated with lower levels of placental parasitemia. The difference in kinetics of antibody production between primigravidae and multigravidae correlated with the prevalence of malaria in these groups, suggesting that antibodies are produced during pregnancy in response to placental infection. The early onset of efficient antibody response in multigravidae and the delayed production to antibodies in primigravidae appear to account for the gravidity-dependent differential susceptibilities of pregnant women to placental malaria.

  16. Tensile loading modulates bone marrow stromal cell differentiation and the development of engineered fibrocartilage constructs.

    PubMed

    Connelly, John T; Vanderploeg, Eric J; Mouw, Janna K; Wilson, Christopher G; Levenston, Marc E

    2010-06-01

    Mesenchymal progenitors such as bone marrow stromal cells (BMSCs) are an attractive cell source for fibrocartilage tissue engineering, but the types or combinations of signals required to promote fibrochondrocyte-specific differentiation remain unclear. The present study investigated the influences of cyclic tensile loading on the chondrogenesis of BMSCs and the development of engineered fibrocartilage. Cyclic tensile displacements (10%, 1 Hz) were applied to BMSC-seeded fibrin constructs for short (24 h) or extended (1-2 weeks) periods using a custom loading system. At early stages of chondrogenesis, 24 h of cyclic tension stimulated both protein and proteoglycan synthesis, but at later stages, tension increased protein synthesis only. One week of intermittent cyclic tension significantly increased the total sulfated glycosaminoglycan and collagen contents in the constructs, but these differences were lost after 2 weeks of loading. Constraining the gels during the extended culture periods prevented contraction of the fibrin matrix, induced collagen fiber alignment, and increased sulfated glycosaminoglycan release to the media. Cyclic tension specifically stimulated collagen I mRNA expression and protein synthesis, but had no effect on collagen II, aggrecan, or osteocalcin mRNA levels. Overall, these studies suggest that the combination of chondrogenic stimuli and tensile loading promotes fibrochondrocyte-like differentiation of BMSCs and has the potential to direct fibrocartilage development in vitro.

  17. Matrix detachment and proteasomal inhibitors diminish Sulf-2 expression in breast cancer cell lines and mouse xenografts

    PubMed Central

    Khurana, Ashwani; Jung-Beom, Deok; He, Xiaoping; Kim, Sung-Hoon; Busby, Robert C.; Lorenzon, Laura; Villa, Massimo; Baldi, Alfonso; Molina, Julian; Goetz, Matthew P.; Shridhar, Viji

    2013-01-01

    Sulfatase 2 (Sulf-2) has been previously shown to be upregulated in breast cancer. Sulf-2 removes sulfate moieties on heparan sulfate proteoglycans which in turn modulate heparin binding growth factor signaling. Here we report that matrix detachment resulted in decreased Sulf-2 expression in breast cancer cells and increased cleavage of poly ADP-ribose polymerase. Silencing of Sulf-2 promotes matrix detachment induced cell death in MCF10DCIS cells. In an attempt to identify Sulf-2 specific inhibitor, we found that proteasomal inhibitors such as MG132, Lactacystin and Bortezomib treatment abolished Sulf-2 expression in multiple breast cancer cell lines. Additionally, we show that Bortezomib treatment of MCF10DCIS cell xenografts in mouse mammary fat pads significantly reduced tumor size, caused massive apoptosis and more importantly reduced Sulf-2 levels in vivo. Finally, our immunohistochemistry analysis of Sulf-2 expression in cohort of patient derived breast tumors indicates that Sulf-2 is significantly upregulated in autologous metastatic lesions compared to primary tumors (p < 0.037, Pearson correlation, Chi-Square analysis). In all, our data suggest that Sulf-2 might play an important role in breast cancer progression from ductal carcinoma in situ into an invasive ductal carcinoma potentially by resisting cell death. PMID:23412907

  18. Different patterns of collagen-proteoglycan interaction: a scanning electron microscopy and atomic force microscopy study.

    PubMed

    Raspanti, M; Congiu, T; Alessandrini, A; Gobbi, P; Ruggeri, A

    2000-01-01

    The extracellular matrix of unfixed, unstained rat corneal stroma, visualized with high-resolution scanning electron microscopy and atomic force microscopy after minimal preliminary treatment, appears composed of straight, parallel, uniform collagen fibrils regularly spaced by a three-dimensional, irregular network of thin, delicate proteoglycan filaments. Rat tail tendon, observed under identical conditions, appears instead made of heterogeneous, closely packed fibrils interwoven with orthogonal proteoglycan filaments. Pre-treatment with cupromeronic blue just thickens the filaments without affecting their spatial layout. Digestion with chondroitinase ABC rids the tendon matrix of all its interconnecting filaments while the corneal stroma architecture remains virtually unaffected, its fibrils always being separated by an evident interfibrillar spacing which is never observed in tendon. Our observations indicate that matrix proteoglycans are responsible for both the highly regular interfibrillar spacing which is distinctive of corneal stroma, and the strong interfibrillar binding observed in tendon. These opposite interaction patterns appear to be distinctive of different proteoglycan species. The molecular details of proteoglycan interactions are still incompletely understood and are the subject of ongoing research.

  19. Decorin Content and Near Infrared Spectroscopy Analysis of Dried Collagenous Biomaterial Samples

    PubMed Central

    Aldema-Ramos, Mila L.; Castell, Joan Carles; Muir, Zerlina E.; Adzet, Jose Maria; Sabe, Rosa; Schreyer, Suzanne

    2012-01-01

    The efficient removal of proteoglycans, such as decorin, from the hide when processing it to leather by traditional means is generally acceptable and beneficial for leather quality, especially for softness and flexibility. A patented waterless or acetone dehydration method that can generate a product similar to leather called Dried Collagenous Biomaterial (known as BCD) was developed but has no effect on decorin removal efficiency. The Alcian Blue colorimetric technique was used to assay the sulfated glycosaminoglycan (sGAG) portion of decorin. The corresponding residual decorin content was correlated to the mechanical properties of the BCD samples and was comparable to the control leather made traditionally. The waterless dehydration and instantaneous chrome tanning process is a good eco-friendly alternative to transforming hides to leather because no additional effects were observed after examination using NIR spectroscopy and additional chemometric analysis. PMID:24970152

  20. Eradication of melanomas by targeted elimination of a minor subset of tumor cells

    PubMed Central

    Schmidt, Patrick; Kopecky, Caroline; Hombach, Andreas; Zigrino, Paola; Mauch, Cornelia; Abken, Hinrich

    2011-01-01

    Proceeding on the assumption that all cancer cells have equal malignant capacities, current regimens in cancer therapy attempt to eradicate all malignant cells of a tumor lesion. Using in vivo targeting of tumor cell subsets, we demonstrate that selective elimination of a definite, minor tumor cell subpopulation is particularly effective in eradicating established melanoma lesions irrespective of the bulk of cancer cells. Tumor cell subsets were specifically eliminated in a tumor lesion by adoptive transfer of engineered cytotoxic T cells redirected in an antigen-restricted manner via a chimeric antigen receptor. Targeted elimination of less than 2% of the tumor cells that coexpress high molecular weight melanoma-associated antigen (HMW-MAA) (melanoma-associated chondroitin sulfate proteoglycan, MCSP) and CD20 lastingly eradicated melanoma lesions, whereas targeting of any random 10% tumor cell subset was not effective. Our data challenge the biological therapy and current drug development paradigms in the treatment of cancer. PMID:21282657

  1. Syndecan promotes axon regeneration by stabilizing growth cone migration

    PubMed Central

    Edwards, Tyson J.; Hammarlund, Marc

    2014-01-01

    SUMMARY Growth cones facilitate the repair of nervous system damage by providing the driving force for axon regeneration. Using single-neuron laser axotomy and in vivo time-lapse imaging, we show that syndecan, a heparan sulfate (HS) proteoglycan, is required for growth cone function during axon regeneration in C. elegans. In the absence of syndecan, regenerating growth cones form but are unstable and collapse, decreasing the effective growth rate and impeding regrowth to target cells. We provide evidence that syndecan has two distinct functions during axon regeneration: 1) a canonical function in axon guidance that requires expression outside the nervous system and depends on HS chains, and 2) a novel intrinsic function in growth cone stabilization that is mediated by the syndecan core protein, independently of HS. Thus, syndecan is a novel regulator of a critical choke point in nervous system repair. PMID:25001284

  2. Syndecan promotes axon regeneration by stabilizing growth cone migration.

    PubMed

    Edwards, Tyson J; Hammarlund, Marc

    2014-07-10

    Growth cones facilitate the repair of nervous system damage by providing the driving force for axon regeneration. Using single-neuron laser axotomy and in vivo time-lapse imaging, we show that syndecan, a heparan sulfate (HS) proteoglycan, is required for growth cone function during axon regeneration in C. elegans. In the absence of syndecan, regenerating growth cones form but are unstable and collapse, decreasing the effective growth rate and impeding regrowth to target cells. We provide evidence that syndecan has two distinct functions during axon regeneration: (1) a canonical function in axon guidance that requires expression outside the nervous system and depends on HS chains and (2) an intrinsic function in growth cone stabilization that is mediated by the syndecan core protein, independently of HS. Thus, syndecan is a regulator of a critical choke point in nervous system repair. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Proteoglycans in polarized epithelial Madin-Darby canine kidney cells.

    PubMed Central

    Svennevig, K; Prydz, K; Kolset, S O

    1995-01-01

    Madin-Darby canine kidney (MDCK) cells were cultured on polycarbonate filters to study the synthesis and sorting of proteoglycans in polarized epithelial cells. Two strains of MDCK cells were used. MDCK I cells resemble distal tubule epithelial cells, and MDCK II cells share some characteristics with proximal tubule cells. Both strains were grown to confluency and labelled with [35S]sulphate for 24 h. The apical and basolateral media and the cell fractions were harvested and analysed by DEAE ion-exchange chromatography. A large portion of the [35S]sulphate-labelled macromolecules bound strongly to the ion-exchange columns, and could be eluted in three distinct peaks. The latest eluting peak was demonstrated to contain almost exclusively chondroitin sulphate, whereas peak 2 contained mostly heparan sulphate, demonstrated by using chondroitinase ABC and nitrous acid (pH 1.5) respectively to depolymerize the [35S]glycosaminoglycan chains. Peak 1 contained negligible amounts of proteoglycans. Large differences could be observed in proteoglycan sorting in MDCK I and II cells. Strain I secreted approx. 67% of the proteoglycans to the apical side and 17% to the basolateral side. The cell fraction contained 17% of the proteoglycans after 24 h of labelling. In contrast, 19% of the proteoglycans were sorted to the apical side of MDCK II cells and 61% to the basolateral side, whereas the cell fraction contained 20%. Furthermore, the level of [35S]proteoglycan biosynthesis (apical and basolateral media and cell fraction total) was higher in MDCK I cells than in strain II. Based on the amount of material degraded by chondroitinase ABC and nitrous acid respectively, and the total amounts of [35S]proteoglycans recovered from the cells, it was calculated that the MDCK I strain synthesized approx. 56% chondroitin sulphate and 44% heparan sulphate. In contrast, the MDCK II strain synthesized 69% heparan sulphate and 31% chondroitin sulphate. To further identify the [35S]proteoglycans synthesized by MDCK I and II cells, antibodies against perlecan, versican and syndecan were used. The antibody against mouse syndecan did not cross-react with any of the proteoglycans produced in MDCK I or II cells. Both MDCK I and II cells expressed perlecan; 57-61% could be recovered from the basolateral fractions and 18-34% from the apical medium. Versican was also found in both MDCK I and II cells. Compared with perlecan, a larger percentage of versican (43-53%) was found in the cell fractions. Images Figure 3 Figure 4 Figure 5 Figure 6 PMID:7487945

  4. The extracellular matrix of rat pacinian corpuscles: an analysis of its fine structure.

    PubMed

    Dubový, P; Bednárová, J

    1999-12-01

    The Pacinian corpuscle consists of a sensory axon terminal that is enveloped by two different structures, the inner core and the capsule. Since proteoglycans are extremely water soluble and are extracted by conventional methods for electron microscopy, the current picture of the structural composition of the extracellular matrix in the inner core and the capsule of the Pacinian corpuscle is incomplete. To study the structural composition of the extracellular matrix of the Pacinian corpuscles, cationic dyes (ruthenium red, alcian blue, acridine orange) and tannic acid were applied simultaneously with the aldehyde fixation. The interosseal Pacinian corpuscles of the rat were fixed either in 2% formaldehyde and 1.5% glutaraldehyde, with the addition of one of these cationic dyes or, in Zamboni's fixative, with tannic acid added. The cationic dyes and tannic acid revealed a different structural pattern of proteoglycans in the extracellular matrix in the inner core and in the capsule of the rat Pacinian corpuscles. The inner core surrounding the sensory axon terminal is a compartment containing proteoglycans that were distributed not only in the extracellular matrix but also in the cytoplasm of the lamellae. In addition, this excitable domain was separated from the capsular fluid by a thick layer of proteoglycans on its surface. An enlarged interlamellar space of the capsule contained large amounts of proteoglycans that were removed by digestion with chondroitinase-ABC. Ruthenium red and alcian blue provided only electron dense granules, probably corresponding to collapsed monomeric proteoglycan molecules. Acridine orange and tannic acid preserved proteoglycans very well and made it possible to visualize them as "bottlebrush" structures in the electron microscope. These results show that the inner core and the capsule of rat Pacinian corpuscles have different structural patterns of proteoglycans, which are probably involved in different functions.

  5. High-oleic canola oil consumption enriches LDL particle cholesteryl oleate content and reduces LDL proteoglycan binding in humans

    PubMed Central

    Jones, Peter J. H.; MacKay, Dylan. S.; Senanayake, Vijitha K.; Pu, Shuaihua; Jenkins, David J. A.; Connelly, Philip W.; Lamarche, Benoît; Couture, Patrick; Kris-Etherton, Penny M.; West, Sheila G.; Liu, Xiaoran; Fleming, Jennifer A.; Hantgan, Roy R.; Rudel, Lawrence L.

    2015-01-01

    Oleic acid consumption is considered cardio-protective according to studies conducted examining effects of the Mediterranean diet. However, animal models have shown that oleic acid consumption increases LDL particle cholesteryl oleate content which is associated with increased LDL-proteoglycan binding and atherosclerosis. The objective was to examine effects of varying oleic, linoleic and docosahexaenoic acid consumption on human LDL-proteoglycan binding in a non-random subset of the Canola Oil Multi-center Intervention Trial (COMIT) participants. COMIT employed a randomized, double-blind, five-period, cross-over trial design. Three of the treatment oil diets; 1) a blend of corn/safflower oil (25:75); 2) high oleic canola oil; and 3) DHA-enriched high oleic canola oil were selected for analysis of LDL-proteoglycan binding in 50 participants exhibiting good compliance. LDL particles were isolated from frozen plasma by gel filtration chromatography and LDL cholesteryl esters quantified by mass-spectrometry. LDL-proteoglycan binding was assessed using surface plasmon resonance. LDL particle cholesterol ester fatty acid composition was sensitive to the treatment fatty acid compositions, with the main fatty acids in the treatments increasing in the LDL cholesterol esters. The corn/safflower oil and high-oleic canola oil diets lowered LDL-proteoglycan binding relative to their baseline values (p=0.0005 and p=0.0012, respectively). At endpoint, high-oleic canola oil feeding resulted in lower LDL-proteoglycan binding than corn/safflower oil (p=0.0243) and DHA-enriched high oleic canola oil (p=0.0249), although high-oleic canola oil had the lowest binding at baseline (p=0.0344). Our findings suggest that high-oleic canola oil consumption in humans increases cholesteryl oleate percentage in LDL, but in a manner not associated with a rise in LDL-proteoglycan binding. PMID:25528432

  6. Large proteoglycan complexes and disturbed collagen architecture in the corneal extracellular matrix of mucopolysaccharidosis type VII (Sly syndrome).

    PubMed

    Young, Robert D; Liskova, Petra; Pinali, Christian; Palka, Barbara P; Palos, Michalis; Jirsova, Katerina; Hrdlickova, Enkela; Tesarova, Marketa; Elleder, Milan; Zeman, Jiri; Meek, Keith M; Knupp, Carlo; Quantock, Andrew J

    2011-08-24

    Deficiencies in enzymes involved in proteoglycan (PG) turnover underlie a number of rare mucopolysaccharidoses (MPS), investigations of which can considerably aid understanding of the roles of PGs in corneal matrix biology. Here, the authors analyze novel pathologic changes in MPS VII (Sly syndrome) to determine the nature of PG-collagen associations in stromal ultrastructure. Transmission electron microscopy and electron tomography were used to investigate PG-collagen architectures and interactions in a cornea obtained at keratoplasty from a 22-year-old man with MPS VII, which was caused by a compound heterozygous mutation in the GUSB gene. Transmission electron microscopy showed atypical morphology of the epithelial basement membrane and Bowman's layer in MPS VII. Keratocytes were packed with cytoplasmic vacuoles containing abnormal glycosaminoglycan (GAG) material, and collagen fibrils were thinner than in normal cornea and varied considerably throughout anterior (14-32 nm), mid (13-42 nm), and posterior (17-39 nm) regions of the MPS VII stroma. PGs viewed in three dimensions were striking in appearance in that they were significantly larger than PGs in normal cornea and formed highly extended linkages with multiple collagen fibrils. Cellular changes in the MPS VII cornea resemble those in other MPS. However, the wide range of collagen fibril diameters throughout the stroma and the extensive matrix presence of supranormal-sized PG structures appear to be unique features of this disorder. The findings suggest that the accumulation of stromal chondroitin-, dermatan-, and heparan-sulfate glycosaminoglycans in the absence of β-glucuronidase-mediated degradation can modulate collagen fibrillogenesis.

  7. Molecular pathways of platelet factor 4/CXCL4 signaling.

    PubMed

    Kasper, Brigitte; Petersen, Frank

    2011-01-01

    The platelet-derived chemokine CXCL4 takes a specific and unique position within the family of chemotactic cytokines. Today, much attention is directed to CXCL4's capacity to inhibit angiogenesis and to promote innate immune responses, which makes this chemokine an interesting tool and target for potential intervention in tumor growth and inflammation. However, such attempts demand a comprehensive knowledge on the molecular mechanisms and pathways underlying the corresponding cellular functions. At least two structurally different receptors, CXCR3-B and a chondroitin sulfate proteoglycan, are capable of binding CXCL4 and to induce a specific intracellular signaling machinery. While signaling mediated by CXCR3-B involves Gs proteins, elevated cAMP levels, and p38 MAP kinase, signaling via proteoglycans appears to be more complicated and varies strongly between the cell types analyzed. In CXCL4-activated neutrophils and monocytes, tyrosine kinases of the Src family and Syk as well as monomeric GTPases and members of the MAP kinase family have been identified as essential intracellular signals. Most intriguingly, signaling does not proceed in a linear sequence of events but in a repeated activation of certain transducing elements like Rac2 or sphingosine kinase 1. Depending on the downstream targets, such biphasic kinetics either leads to a redundant and prolonged activation of a single pathway or to a timely separated initiation of disparate signals and functions. Results of the studies reviewed here help to understand the molecular basis of CXCL4's functional diversity and provide insights into integrated signaling processes in general. Copyright © 2011 Elsevier GmbH. All rights reserved.

  8. Vocal fold proteoglycans and their influence on biomechanics.

    PubMed

    Gray, S D; Titze, I R; Chan, R; Hammond, T H

    1999-06-01

    To examine the interstitial proteins of the vocal fold and their influence on the biomechanical properties of that tissue. Anatomic study of the lamina propria of human cadaveric vocal folds combined with some viscosity testing. Identification of proteoglycans is performed with histochemical staining. Quantitative analysis is performed using an image analysis system. A rheometer is used for viscosity testing. Three-dimensional rendering program is used for the computer images. Proteoglycans play an important role in tissue biomechanics. Hyaluronic acid is a key molecule that affects viscosity. The proteoglycans of the lamina propria have important biological and biomechanical effects. The role of hyaluronic acid in determining tissue viscosity is emphasized. Viscosity, its effect on phonatory threshold pressure and energy expended due to phonation is discussed. Proteoglycans, particularly hyaluronic acid, play important roles in determining biomechanical properties of tissue oscillation. Future research will likely make these proteins of important therapeutic interest.

  9. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cintron, C.; Hong, B.S.; Covington, H.I.

    Whole neonate rabbit corneas and adult corneas containing 2-week-old scars were incubated in the presence of (/sup 14/C) glycine. Radiolabeled collagen extracted from the corneas and scar tissue were analyzed by sodium dodecylsulfate/polyacrylamide gel electrophoresis and fluorography to determine the types and relative quantity of collagen polypeptides present and synthesized by these tissues. In addition to other collagen types, type III was found in both neonate cornea and scar tissue from adult cornea, albeit in relatively small quantities. Type III collagen in normal cornea was associated with the residue after pepsin digestion and formic acid extraction of the tissue, andmore » the same type of collagen was extracted from scar tissue after similar treatment. Type III collagen-specific monoclonal antibody bound to developing normal corneas and healing adult tissue sections, as determined by immunofluorescence. Antibody binding was localized to the endothelium and growing Descemet's membrane in fetal and neonate corneas, and restricted to the most posterior region of the corneal scar tissue. Although monoclonal antibody to keratan sulfate, used as a marker for stromal fibroblasts, bound to most of the scar tissue, the antibody failed to bind to the posterior scar tissue positive for type III collagen. We conclude that endothelial cells from fetal and neonate rabbit cornea and endothelium-derived fibroblasts from healing wounds of adult cornea synthesize and deposit type III collagen. Moreover, this collagen appears to be incorporated into the growing Descemet's membrane of normal corneas and narrow posterior portion of the scar tissue.« less

  10. Keratocyte behavior in three-dimensional photopolymerizable poly(ethylene glycol) hydrogels

    PubMed Central

    Thibault, Richard; Ambrose, Winnette McIntosh; Schein, Oliver D.; Chakravarti, Shukti; Elisseeff, Jennifer

    2015-01-01

    The goal of this study was to evaluate three-dimensional (3-D) poly(ethylene glycol) (PEG) hydrogels as a culture system for studying corneal keratocytes. Bovine keratocytes were subcultured in DMEM/F-12 containing 10% fetal bovine serum (FBS) through passage 5. Primary keratocytes (P0) and corneal fibroblasts from passages 1 (P1) and 3 (P3) were photoencapsulated at various cell concentrations in PEG hydrogels via brief exposure to light. Additional hydrogels contained adhesive YRGDS and nonadhesive YRDGS peptides. Hydrogel constructs were cultured in DMEM/F-12 with 10% FBS for 2 and 4 weeks. Cell viability was assessed by DNA quantification and vital staining. Biglycan, type I collagen, type III collagen, keratocan and lumican expression were determined by reverse transcriptase–polymerase chain reaction. Deposition of type I collagen, type III collagen and keratan sulfate (KS)-containing matrix components was visualized using confocal microscopy. Keratocytes in a monolayer lost their stellate morphology and keratocan expression, displayed elongated cell bodies, and up-regulated biglycan, type I collagen and type III collagen characteristic of corneal fibroblasts. Encapsulated keratocytes remained viable for 4 weeks with spherical morphologies. Hydrogels supported production of KS, type I collagen and type III collagen matrix components. PEG-based hydrogels can support keratocyte viability and matrix production. 3-D hydrogel culture can stabilize but not restore the keratocyte phenotype. This novel application of PEG hydrogels has potential use in the study of corneal keratocytes in a 3-D environment. PMID:18567550

  11. Multiple chimeric antigen receptors successfully target chondroitin sulfate proteoglycan 4 in several different cancer histologies and cancer stem cells

    PubMed Central

    2014-01-01

    Background The development of immunotherapy has led to significant progress in the treatment of metastatic cancer, including the development of genetic engineering technologies that redirect lymphocytes to recognize and target a wide variety of tumor antigens. Chimeric antigen receptors (CARs) are hybrid proteins combining antibody recognition domains linked to T cell signaling elements. Clinical trials of CAR-transduced peripheral blood lymphocytes (PBL) have induced remission of both solid organ and hematologic malignancies. Chondroitin sulfate proteoglycan 4 (CSPG4) is a promising target antigen that is overexpressed in multiple cancer histologies including melanoma, triple-negative breast cancer, glioblastoma, mesothelioma and sarcoma. Methods CSPG4 expression in cancer cell lines was assayed using flow cytometry (FACS) and reverse-transcription PCR (RT-PCR). Immunohistochemistry was utilized to assay resected melanomas and normal human tissues (n = 30) for CSPG4 expression and a reverse-phase protein array comprising 94 normal tissue samples was also interrogated for CSPG4 expression. CARs were successfully constructed from multiple murine antibodies (225.28S, TP41.2, 149.53) using second generation (CD28.CD3ζ) signaling domains. CAR sequences were cloned into a gamma-retroviral vector with subsequent successful production of retroviral supernatant and PBL transduction. CAR efficacy was assayed by cytokine release and cytolysis following coculture with target cell lines. Additionally, glioblastoma stem cells were generated from resected human tumors, and CSPG4 expression was determined by RT-PCR and FACS. Results Immunohistochemistry demonstrated prominent CSPG4 expression in melanoma tumors, but failed to demonstrate expression in any of the 30 normal human tissues studied. Two of 94 normal tissue protein lysates were positive by protein array. CAR constructs demonstrated cytokine secretion and cytolytic function after co-culture with tumor cell lines from multiple different histologies, including melanoma, breast cancer, mesothelioma, glioblastoma and osteosarcoma. Furthermore, we report for the first time that CSPG4 is expressed on glioblastoma cancer stem cells (GSC) and demonstrate that anti-CSPG4 CAR-transduced T cells recognize and kill these GSC. Conclusions The functionality of multiple different CARs, with the widespread expression of CSPG4 on multiple malignancies, suggests that CSPG4 may be an attractive candidate tumor antigen for CAR-based immunotherapies using appropriate technology to limit possible off-tumor toxicity. PMID:25197555

  12. Effect of body temperature on chondroitinase ABC's ability to cleave chondroitin sulfate glycosaminoglycans.

    PubMed

    Tester, Nicole J; Plaas, Anna H; Howland, Dena R

    2007-04-01

    Chondroitinase ABC (Ch'ase ABC) is a bacterial lyase that degrades chondroitin sulfate (CS), dermatan sulfate, and hyaluronan glycosaminoglycans (GAGs). This enzyme has received significant attention as a potential therapy for promoting central nervous system and peripheral nervous system repair based on its degradation of CS GAGs. Determination of the stability of Ch'ase ABC activity at temperatures equivalent to normal (37 degrees C) and elevated (39 degrees C) body temperatures is important for optimizing its clinical usage. We report here data obtained from examining enzymatic activity at these temperatures across nine lots of commercially available protease-free Ch'ase ABC. CS GAG degrading activity was assayed by using 1) immunohistochemical detection of unsaturated disaccharide stubs generated by digestion of proteoglycans in tissue sections and 2) fluorophore-assisted carbohydrate electrophoresis (FACE) and/or high-performance liquid chromatography (HPLC) to separate and quantify unsaturated disaccharide digestion products. Our results indicate that there is a significant effect of lot and time on enzymatic thermostability. Average enzymatic activity is significantly decreased at 1 and 3 days at 39 degrees C and 37 degrees C, respectively. Furthermore, the average activity seen after 1 day was significantly different between the two temperatures. Addition of bovine serum albumin as a stabilizer significantly preserved enzymatic activity at 1 day, but not 3 days, at 39 degrees C. These results show that the CS GAG degrading activity of Ch'ase ABC is significantly decreased with incubation at body temperature over time and that all lots do not show equal thermostability. These findings are important for the design and interpretation of experimental and potential clinical studies involving Ch'ase ABC. (c) 2007 Wiley-Liss, Inc.

  13. Spatiotemporal expression of chondroitin sulfate sulfotransferases in the postnatal developing mouse cerebellum.

    PubMed

    Ishii, Maki; Maeda, Nobuaki

    2008-08-01

    Chondroitin sulfate (CS) proteoglycans are major components of the cell surface and the extracellular matrix in the developing brain and bind to various proteins via CS chains in a CS structure-dependent manner. This study demonstrated the expression pattern of three CS sulfotransferase genes, dermatan 4-O-sulfotransferase (D4ST), uronyl 2-O-sulfotransferase (UST), and N-acetylgalactosamine 4-sulfate 6-O-sulfotransferase (GalNAc4S-6ST), in the mouse postnatal cerebellum. These sulfotransferases are responsible for the biosynthesis of oversulfated structures in CS chains such as B, D, and E units, which constitute the binding sites for various heparin-binding proteins. Real-time reverse transcription-polymerase chain reaction analysis indicated that the expression of UST increased remarkably during cerebellar development. The amounts of B and D units, which are generated by UST activity, in the cerebellar CS chains also increased during development. In contrast, the expression of GalNAc4S-6ST and its biosynthetic product, E unit, decreased during postnatal development. In situ hybridization experiments revealed the levels of UST and GalNAc4S-6ST mRNAs to correlate inversely in many cells including Purkinje cells, granule cells in the external granular layer, and inhibitory interneurons. In these neurons, the expression of UST increased and that of GalNAc4S-6ST decreased during development and/or maturation. D4ST was also expressed by many neurons, but its expression was not simply correlated with development, which might contribute to the diversification of CS structures expressed by distinct neurons. These results suggest that the CS structures of various cerebellar neurons change during development and such changes of CS are involved in the regulation of various signaling pathways.

  14. The Synthetic Antimicrobial Peptide 19-2.5 Interacts with Heparanase and Heparan Sulfate in Murine and Human Sepsis.

    PubMed

    Martin, Lukas; De Santis, Rebecca; Koczera, Patrick; Simons, Nadine; Haase, Hajo; Heinbockel, Lena; Brandenburg, Klaus; Marx, Gernot; Schuerholz, Tobias

    2015-01-01

    Heparanase is an endo-β-glucuronidase that cleaves heparan sulfate side chains from their proteoglycans. Thereby, heparanase liberates highly potent circulating heparan sulfate-fragments (HS-fragments) and triggers the fatal and excessive inflammatory response in sepsis. As a potential anti-inflammatory agent for sepsis therapy, peptide 19-2.5 belongs to the class of synthetic anti-lipopolysaccharide peptides; however, its activity is not restricted to Gram-negative bacterial infection. We hypothesized that peptide 19-2.5 interacts with heparanase and/or HS, thereby reducing the levels of circulating HS-fragments in murine and human sepsis. Our data indicate that the treatment of septic mice with peptide 19-2.5 compared to untreated control animals lowers levels of plasma heparanase and circulating HS-fragments and reduces heparanase activity. Additionally, mRNA levels of heparanase in heart, liver, lung, kidney and spleen are downregulated in septic mice treated with peptide 19-2.5 compared to untreated control animals. In humans, plasma heparanase level and activity are elevated in septic shock. The ex vivo addition of peptide 19-2.5 to plasma of septic shock patients decreases heparanase activity but not heparanase level. Isothermal titration calorimetry revealed a strong exothermic reaction between peptide 19-2.5 and heparanase and HS-fragments. However, a saturation character has been identified only in the peptide 19-2.5 and HS interaction. In conclusion, the findings of our current study indicate that peptide 19-2.5 interacts with heparanase, which is elevated in murine and human sepsis and consecutively attenuates the generation of circulating HS-fragments in systemic inflammation. Thus, peptide 19-2.5 seems to be a potential anti-inflammatory agent in sepsis.

  15. A Network of HSPG Core Proteins and HS Modifying Enzymes Regulates Netrin-Dependent Guidance of D-Type Motor Neurons in Caenorhabditis elegans

    PubMed Central

    Gysi, Stephan; Rhiner, Christa; Flibotte, Stephane; Moerman, Donald G.; Hengartner, Michael O.

    2013-01-01

    Heparan sulfate proteoglycans (HSPGs) are proteins with long covalently attached sugar side chains of the heparan sulfate (HS) type. Depending on the cellular context HS chains carry multiple structural modifications such as sulfate residues or epimerized sugars allowing them to bind to a wide range of molecules. HSPGs have been found to play extremely diverse roles in animal development and were shown to interact with certain axon guidance molecules. In this study we describe the role of the Caenorhabditis elegans HSPG core proteins Syndecan (SDN-1) and Glypican (LON-2) and the HS modifying enzymes in the dorsal guidance of D-type motor axons, a process controlled mainly by the conserved axon guidance molecule UNC-6/Netrin. Our genetic analysis established the specific HS code relevant for this axon guidance event. Using two sensitized genetic backgrounds, we isolated novel components influencing D-type motor axon guidance with a link to HSPGs, as well as new alleles of several previously characterized axon guidance genes. Interestingly, the dorsal axon guidance defects induced by mutations in zfp-1 or lin-35 depended on the transgene oxIs12 used to visualize the D-type motor neurons. oxIs12 is a large multi-copy transgene that enlarges the X chromosome by approximately 20%. In a search for genes with a comparable phenotype we found that a mutation in the known dosage compensation gene dpy-21 showed similar axon guidance defects as zfp-1 or lin-35 mutants. Thus, derepression of genes on X, where many genes relevant for HS dependent axon guidance are located, might also influence axon guidance of D-type motor neurons. PMID:24066155

  16. Software for peak finding and elemental composition assignment for glycosaminoglycan tandem mass spectra.

    PubMed

    Hogan, John D; Klein, Joshua A; Wu, Jiandong; Chopra, Pradeep; Boons, Geert-Jan; Carvalho, Luis; Lin, Cheng; Zaia, Joseph

    2018-04-03

    Glycosaminoglycans (GAGs) covalently linked to proteoglycans (PGs) are characterized by repeating disaccharide units and variable sulfation patterns along the chain. GAG length and sulfation patterns impact disease etiology, cellular signaling, and structural support for cells. We and others have demonstrated the usefulness of tandem mass spectrometry (MS2) for assigning the structures of GAG saccharides; however, manual interpretation of tandem mass spectra is time-consuming, so computational methods must be employed. In the proteomics domain, the identification of monoisotopic peaks and charge states relies on algorithms that use averagine, or the average building block of the compound class being analyzed. While these methods perform well for protein and peptide spectra, they perform poorly on GAG tandem mass spectra, due to the fact that a single average building block does not characterize the variable sulfation of GAG disaccharide units. In addition, it is necessary to assign product ion isotope patterns in order to interpret the tandem mass spectra of GAG saccharides. To address these problems, we developed GAGfinder, the first tandem mass spectrum peak finding algorithm developed specifically for GAGs. We define peak finding as assigning experimental isotopic peaks directly to a given product ion composition, as opposed to deconvolution or peak picking, which are terms more accurately describing the existing methods previously mentioned. GAGfinder is a targeted, brute force approach to spectrum analysis that utilizes precursor composition information to generate all theoretical fragments. GAGfinder also performs peak isotope composition annotation, which is typically a subsequent step for averagine-based methods. Data are available via ProteomeXchange with identifier PXD009101. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Acid glycosaminoglycan (aGAG) excretion is increased in children with autism spectrum disorder, and it can be controlled by diet.

    PubMed

    Endreffy, Ildikó; Bjørklund, Geir; Dicső, Ferenc; Urbina, Mauricio A; Endreffy, Emőke

    2016-04-01

    Autism research continues to receive considerable attention as the options for successful management are limited. The understanding of the autism spectrum disorder (ASD) etiology has now progressed to encompass genetic, epigenetic, neurological, hormonal, and environmental factors that affect outcomes for patients with ASD. Glycosaminoglycans (GAGs) are a family of linear, sulfated polysaccharides that are associated with central nervous system (CNS) development, maintenance, and disorders. Proteoglycans (PG) regulate diverse functions in the central nervous system. Heparan sulfate (HS) and chondroitin sulfate (CS) are two major GAGs present in the PGs of the CNS. As neuroscience advances, biochemical treatments to correct brain chemistry become better defined. Nutrient therapy can be very potent and has minimal to no side effects, since no molecules foreign to the body are needed. Given GAGs are involved in several neurological functions, and that its level can be somewhat modulated by the diet, the present study aimed to evaluate the role of GAGs levels in ASD symptoms. Both tGAG and its different fractions were evaluated in the urine of ASD and healthy control childrens. As levels differed between groups, a second trial was conduted evaluating if diet could reduce tGAG levels and if this in turn decrease ASD symptoms. The present study found that tGAG concentration was significantly higher in the urine of children with ASD compared to healthy control children and this was also evident in all GAG fractions. Within groups (controls and ASD), no gender differences in GAG excretion were found. The use of a 90 days elimination diet (casein-free, special carbohydrates, multivitamin/mineral supplement), had major effects in reducing urinary tGAG excretion in children with ASD.

  18. Interactions of signaling proteins, growth factors and other proteins with heparan sulfate: mechanisms and mysteries.

    PubMed

    Billings, Paul C; Pacifici, Maurizio

    2015-01-01

    Heparan sulfate (HS) is a component of cell surface and matrix-associated proteoglycans (HSPGs) that, collectively, play crucial roles in many physiologic processes including cell differentiation, organ morphogenesis and cancer. A key function of HS is to bind and interact with signaling proteins, growth factors, plasma proteins, immune-modulators and other factors. In doing so, the HS chains and HSPGs are able to regulate protein distribution, bio-availability and action on target cells and can also serve as cell surface co-receptors, facilitating ligand-receptor interactions. These proteins contain an HS/heparin-binding domain (HBD) that mediates their association and contacts with HS. HBDs are highly diverse in sequence and predicted structure, contain clusters of basic amino acids (Lys and Arg) and possess an overall net positive charge, most often within a consensus Cardin-Weintraub (CW) motif. Interestingly, other domains and residues are now known to influence protein-HS interactions, as well as interactions with other glycosaminoglycans, such as chondroitin sulfate. In this review, we provide a description and analysis of HBDs in proteins including amphiregulin, fibroblast growth factor family members, heparanase, sclerostin and hedgehog protein family members. We discuss HBD structural and functional features and important roles carried out by other protein domains, and also provide novel conformational insights into the diversity of CW motifs present in Sonic, Indian and Desert hedgehogs. Finally, we review progress in understanding the pathogenesis of a rare pediatric skeletal disorder, Hereditary Multiple Exostoses (HME), characterized by HS deficiency and cartilage tumor formation. Advances in understanding protein-HS interactions will have broad implications for basic biology and translational medicine as well as for the development of HS-based therapeutics.

  19. Metabolic Effects of Avocado/Soy Unsaponifiables on Articular Chondrocytes

    PubMed Central

    Nardo, Joseph V.; Harlan, Robert; Chiou, Tiffany

    2008-01-01

    Avocado/soy unsaponifiable (ASU) components are reported to have a chondroprotective effect by virtue of anti-inflammatory and proanabolic effects on articular chondrocytes. The identity of the active component(s) remains unknown. In general, sterols, the major component of unsaponifiable plant material have been demonstrated to be anti-inflammatory in vitro and in animal models. These studies were designed to clarify whether the sterol content of ASU preparations were the primary contributors to biological activity in articular chondrocytes. ASU samples were analyzed by high pressure liquid chromatography (HPLC) and GC mass spectrometry. The sterol content was normalized between diverse samples prior to in vitro testing on bovine chondrocytes. Anabolic activity was monitored by uptake of 35-sulfate into proteoglycans and quantitation of labeled hydroxyproline and proline content after incubation with labeled proline. Anti-inflammatory activity was assayed by measuring reduction of interleukin-1 (IL-1)-induced synthesis of PGE2 and metalloproteases and release of label from tissue prelabeled with S-35.All ASU samples exerted a similar time-dependent up-regulation of 35-sulfate uptake in bovine cells reaching a maximum of greater than 100% after 72 h at sterol doses of 1–10 μg/ml. Non-collagenous protein (NCP) and collagen synthesis were similarly up-regulated. All ASU were equally effective in dose dependently inhibiting IL-1-induced MMP-3 activity (23–37%), labeled sulfate release (15–23%) and PGE2 synthesis (45–58%). Up-regulation of glycosaminoglycan and collagen synthesis and reduction of IL-1 effects in cartilage are consistent with chondroprotective activity. The similarity of activity of ASU from diverse sources when tested at equal sterol levels suggests sterols are important for biologic effects in articular chondrocytes. PMID:18604259

  20. Inappropriate claims from non-equivalent medications in osteoarthritis: a position paper endorsed by the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO).

    PubMed

    Bruyère, Olivier; Cooper, Cyrus; Al-Daghri, Nasser M; Dennison, Elaine M; Rizzoli, René; Reginster, Jean-Yves

    2018-02-01

    Osteoarthritis (OA) is a progressive joint disease, that occurs frequently in the aging population and is a major cause of disability worldwide. Both glucosamine and chondroitin are biologically active molecules that are substrates for proteoglycan, an essential component of the cartilage matrix. Evidence supports the use of glucosamine and chondroitin as symptomatic slow-acting drugs for osteoarthritis (SYSADOAs) with impact on OA symptoms and disease-modifying effects in the long term. Glucosamine and chondroitin are administered in exogenous form as a sulfate salt and multiple formulations of these agents are available, both as prescription-grade products and nutritional supplements. However, while all preparations may claim to deliver a therapeutic level of glucosamine or chondroitin not all are supported by clinical evidence. Only patented crystalline glucosamine sulfate (pCGS) is shown to deliver consistently high glucosamine bioavailability and plasma concentration in humans, which corresponds to demonstrated clinical efficacy. Similarly, clinical evidence supports only the pharmaceutical-grade chondroitin sulfate. The European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) advocates, through careful consideration of the evidence base, that judicious choice of glucosamine and chondroitin formulation is essential to maximize clinical benefit, patient adherence and satisfaction with treatment. In future, the ESCEO recommends that complex molecules with biological activity such as pCGS may be treated as "biosimilars" akin to the European Medicines Agency guidance on biological medicinal products. It seems likely that for all other complex molecules classed as SYSADOAs, the recommendation to use only formulations clearly supported by the evidence-base should apply.

  1. Proteoglycomics: Recent Progress and Future Challenges

    PubMed Central

    Ly, Mellisa; Laremore, Tatiana N.

    2010-01-01

    Abstract Proteoglycomics is a systematic study of structure, expression, and function of proteoglycans, a posttranslationally modified subset of a proteome. Although relying on the established technologies of proteomics and glycomics, proteoglycomics research requires unique approaches for elucidating structure–function relationships of both proteoglycan components, glycosaminoglycan chain, and core protein. This review discusses our current understanding of structure and function of proteoglycans, major players in the development, normal physiology, and disease. A brief outline of the proteoglycomic sample preparation and analysis is provided along with examples of several recent proteoglycomic studies. Unique challenges in the characterization of glycosaminoglycan component of proteoglycans are discussed, with emphasis on the many analytical tools used and the types of information they provide. PMID:20450439

  2. Neoproteoglycans in tissue engineering.

    PubMed

    Weyers, Amanda; Linhardt, Robert J

    2013-05-01

    Proteoglycans, comprised of a core protein to which glycosaminoglycan chains are covalently linked, are an important structural and functional family of macromolecules found in the extracellular matrix. Advances in our understanding of biological interactions have lead to a greater appreciation for the need to design tissue engineering scaffolds that incorporate mimetics of key extracellular matrix components. A variety of synthetic and semisynthetic molecules and polymers have been examined by tissue engineers that serve as structural, chemical and biological replacements for proteoglycans. These proteoglycan mimetics have been referred to as neoproteoglycans and serve as functional and therapeutic replacements for natural proteoglycans that are often unavailable for tissue engineering studies. Although neoproteoglycans have important limitations, such as limited signaling ability and biocompatibility, they have shown promise in replacing the natural activity of proteoglycans through cell and protein binding interactions. This review focuses on the recent in vivo and in vitro tissue engineering applications of three basic types of neoproteoglycan structures, protein-glycosaminoglycan conjugates, nano-glycosaminoglycan composites and polymer-glycosaminoglycan complexes. © 2013 The Authors Journal compilation © 2013 FEBS.

  3. Neoproteoglycans in tissue engineering

    PubMed Central

    Weyers, Amanda; Linhardt, Robert J.

    2014-01-01

    Proteoglycans, comprised of a core protein to which glycosaminoglycan chains are covalently linked, are an important structural and functional family of macromolecules found in the extracellular matrix. Advances in our understanding of biological interactions have lead to a greater appreciation for the need to design tissue engineering scaffolds that incorporate mimetics of key extracellular matrix components. A variety of synthetic and semisynthetic molecules and polymers have been examined by tissue engineers that serve as structural, chemical and biological replacements for proteoglycans. These proteoglycan mimetics have been referred to as neoproteoglycans and serve as functional and therapeutic replacements for natural proteoglycans that are often unavailable for tissue engineering studies. Although neoproteoglycans have important limitations, such as limited signaling ability and biocompatibility, they have shown promise in replacing the natural activity of proteoglycans through cell and protein binding interactions. This review focuses on the recent in vivo and in vitro tissue engineering applications of three basic types of neoproteoglycan structures, protein–glycosaminoglycan conjugates, nano-glycosaminoglycan composites and polymer–glycosaminoglycan complexes. PMID:23399318

  4. Characterization of the interactions of type XII collagen with two small proteoglycans from fetal bovine tendon, decorin and fibromodulin.

    PubMed

    Font, B; Eichenberger, D; Rosenberg, L M; van der Rest, M

    1996-11-01

    In addition to the major collagens, such as type I or type II, connective tissues contain a number of less abundant collagens and proteoglycans, whose association contributes to the different properties of the tissues. Type XII and type XIV collagens have been described in soft connective tissues, and type XIV collagen has been shown to interact specifically with decorin through its glycosaminoglycan chain (Font et al., J. Biol. Chem. 268, 25015-25018, 1993). Interactions between these collagens and the small proteoglycans have been characterized further by studying the binding of type XII collagen to decorin by solid phase assays. Our results show a saturable binding of the proteoglycan through its glycosaminoglycan chain to type XII collagen, which does not seem to involve the large non-collagenous NC3 domain of the molecule. This interaction is strongly inhibited by heparin. Furthermore, we report that another small proteoglycan, fibromodulin, isolated from tendon under non-denaturing conditions, is able to bind to type XII collagen. This interaction has been characterized and, unlike that observed with decorin, type XII collagen-fibromodulin interaction seems to take place with the core protein of the proteoglycan. In addition, we report that type XII-type I collagen interactions are not necessarily mediated by decorin as previously suggested.

  5. Novel role of ADAMTS-5 protein in proteoglycan turnover and lipoprotein retention in atherosclerosis.

    PubMed

    Didangelos, Athanasios; Mayr, Ursula; Monaco, Claudia; Mayr, Manuel

    2012-06-01

    Atherosclerosis is initiated by the retention of lipoproteins on proteoglycans in the arterial intima. However, the mechanisms leading to proteoglycan accumulation and lipoprotein retention are poorly understood. In this study, we set out to investigate the role of ADAMTS-5 (a disintegrin and metalloprotease with thrombospondin motifs-5) in the vasculature. ADAMTS-5 was markedly reduced in atherosclerotic aortas of apolipoprotein E-null (apoE(-/-)) mice. The reduction of ADAMTS-5 was accompanied by accumulation of biglycan and versican, the major lipoprotein-binding proteoglycans, in atherosclerosis. ADAMTS-5 activity induced the release of ADAMTS-specific versican (DPEAAE(441)) and aggrecan ((374)ALGS) fragments as well as biglycan and link protein from the aortic wall. Fibroblast growth factor 2 (FGF-2) inhibited ADAMTS-5 expression in isolated aortic smooth muscle cells and blocked the spontaneous release of ADAMTS-generated versican and aggrecan fragments from aortic explants. In aortas of ADAMTS-5-deficient mice, DPEAAE(441) versican neoepitopes were not detectable. Instead, biglycan levels were increased, highlighting the role of ADAMTS-5 in the catabolism of vascular proteoglycans. Importantly, ADAMTS-5 proteolytic activity reduced the LDL binding ability of biglycan and released LDL from human aortic lesions. This study provides the first evidence implicating ADAMTS-5 in the regulation of proteoglycan turnover and lipoprotein retention in atherosclerosis.

  6. Decorin and biglycan retain LDL in disease-prone valvular and aortic subendothelial intimal matrix

    PubMed Central

    Neufeld, Edward B.; Zadrozny, Leah M.; Phillips, Darci; Aponte, Angel; Yu, Zu-Xi; Balaban, Robert S.

    2014-01-01

    Objective Subendothelial LDL retention by intimal matrix proteoglycans is an initial step in atherosclerosis and calcific aortic valve disease. Herein, we identify decorin and biglycan as the proteoglycans that preferentially retain LDL in intimal matrix at disease-prone sites in normal valve and vessel wall. Methods The porcine aortic valve and renal artery ostial diverter, initiation sites of calcific valve disease and renal atherosclerosis, respectively, from normal non-diseased animals were used as models in these studies. Results Fluorescent human LDL was selectively retained on the lesion-prone collagen/proteoglycan-enriched aortic surface of the valve, where the elastic lamina is depleted, as previously observed in lesion-prone sites in the renal ostium. iTRAQ mass spectrometry of valve and diverter protein extracts identified decorin and biglycan as the major subendothelial intimal matrix proteoglycans electrostatically retained on human LDL affinity columns. Decorin levels correlated with LDL binding in lesion-prone sites in both tissues. Collagen binding to LDL was shown to be proteoglycan-mediated. All known basement membrane proteoglycans bound LDL suggesting they may modulate LDL uptake into the subendothelial matrix. The association of purified decorin with human LDL in an in vitro microassay was blocked by serum albumin and heparin suggesting anti-atherogenic roles for these proteins in vivo. Conclusions LDL electrostatic interactions with decorin and biglycan in the valve leaflets and vascular wall is a major source of LDL retention. The complementary electrostatic sites on LDL or these proteoglycans may provide a novel therapeutic target for preventing one of the earliest events in these cardiovascular diseases. PMID:24529131

  7. High-oleic canola oil consumption enriches LDL particle cholesteryl oleate content and reduces LDL proteoglycan binding in humans.

    PubMed

    Jones, Peter J H; MacKay, Dylan S; Senanayake, Vijitha K; Pu, Shuaihua; Jenkins, David J A; Connelly, Philip W; Lamarche, Benoît; Couture, Patrick; Kris-Etherton, Penny M; West, Sheila G; Liu, Xiaoran; Fleming, Jennifer A; Hantgan, Roy R; Rudel, Lawrence L

    2015-02-01

    Oleic acid consumption is considered cardio-protective according to studies conducted examining effects of the Mediterranean diet. However, animal models have shown that oleic acid consumption increases LDL particle cholesteryl oleate content which is associated with increased LDL-proteoglycan binding and atherosclerosis. The objective was to examine effects of varying oleic, linoleic and docosahexaenoic acid consumption on human LDL-proteoglycan binding in a non-random subset of the Canola Oil Multi-center Intervention Trial (COMIT) participants. COMIT employed a randomized, double-blind, five-period, cross-over trial design. Three of the treatment oil diets: 1) a blend of corn/safflower oil (25:75); 2) high oleic canola oil; and 3) DHA-enriched high oleic canola oil were selected for analysis of LDL-proteoglycan binding in 50 participants exhibiting good compliance. LDL particles were isolated from frozen plasma by gel filtration chromatography and LDL cholesteryl esters quantified by mass-spectrometry. LDL-proteoglycan binding was assessed using surface plasmon resonance. LDL particle cholesterol ester fatty acid composition was sensitive to the treatment fatty acid compositions, with the main fatty acids in the treatments increasing in the LDL cholesterol esters. The corn/safflower oil and high-oleic canola oil diets lowered LDL-proteoglycan binding relative to their baseline values (p = 0.0005 and p = 0.0012, respectively). At endpoint, high-oleic canola oil feeding resulted in lower LDL-proteoglycan binding than corn/safflower oil (p = 0.0243) and DHA-enriched high oleic canola oil (p = 0.0249), although high-oleic canola oil had the lowest binding at baseline (p = 0.0344). Our findings suggest that high-oleic canola oil consumption in humans increases cholesteryl oleate percentage in LDL, but in a manner not associated with a rise in LDL-proteoglycan binding. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. Tensile Loading Modulates Bone Marrow Stromal Cell Differentiation and the Development of Engineered Fibrocartilage Constructs

    PubMed Central

    Connelly, John T.; Vanderploeg, Eric J.; Mouw, Janna K.; Wilson, Christopher G.

    2010-01-01

    Mesenchymal progenitors such as bone marrow stromal cells (BMSCs) are an attractive cell source for fibrocartilage tissue engineering, but the types or combinations of signals required to promote fibrochondrocyte-specific differentiation remain unclear. The present study investigated the influences of cyclic tensile loading on the chondrogenesis of BMSCs and the development of engineered fibrocartilage. Cyclic tensile displacements (10%, 1 Hz) were applied to BMSC-seeded fibrin constructs for short (24 h) or extended (1–2 weeks) periods using a custom loading system. At early stages of chondrogenesis, 24 h of cyclic tension stimulated both protein and proteoglycan synthesis, but at later stages, tension increased protein synthesis only. One week of intermittent cyclic tension significantly increased the total sulfated glycosaminoglycan and collagen contents in the constructs, but these differences were lost after 2 weeks of loading. Constraining the gels during the extended culture periods prevented contraction of the fibrin matrix, induced collagen fiber alignment, and increased sulfated glycosaminoglycan release to the media. Cyclic tension specifically stimulated collagen I mRNA expression and protein synthesis, but had no effect on collagen II, aggrecan, or osteocalcin mRNA levels. Overall, these studies suggest that the combination of chondrogenic stimuli and tensile loading promotes fibrochondrocyte-like differentiation of BMSCs and has the potential to direct fibrocartilage development in vitro. PMID:20088686

  9. Heparanase and Syndecan-4 Are Involved in Low Molecular Weight Fucoidan-Induced Angiogenesis

    PubMed Central

    Haddad, Oualid; Guyot, Erwan; Marinval, Nicolas; Chevalier, Fabien; Maillard, Loïc; Gadi, Latifa; Laguillier-Morizot, Christelle; Oudar, Olivier; Sutton, Angela; Charnaux, Nathalie; Hlawaty, Hanna

    2015-01-01

    Induction of angiogenesis is a potential treatment for chronic ischemia. Low molecular weight fucoidan (LMWF), the sulfated polysaccharide from brown seaweeds, has been shown to promote revascularization in a rat limb ischemia, increasing angiogenesis in vivo. We investigated the potential role of two heparan sulfate (HS) metabolism enzymes, exostosin-2 (EXT2) and heparanase (HPSE), and of two HS-membrane proteoglycans, syndecan-1 and -4 (SDC-1 and SDC-4), in LMWF induced angiogenesis. Our results showed that LMWF increases human vascular endothelial cell (HUVEC) migration and angiogenesis in vitro. We report that the expression and activity of the HS-degrading HPSE was increased after LMWF treatment. The phenotypic tests of LMWF-treated and EXT2- or HPSE-siRNA-transfected cells indicated that EXT2 or HPSE expression significantly affect the proangiogenic potential of LMWF. In addition, LMWF increased SDC-1, but decreased SDC-4 expressions. The effect of LMWF depends on SDC-4 expression. Silencing EXT2 or HPSE leads to an increased expression of SDC-4, providing the evidence that EXT2 and HPSE regulate the SDC-4 expression. Altogether, these data indicate that EXT2, HPSE, and SDC-4 are involved in the proangiogenic effects of LMWF, suggesting that the HS metabolism changes linked to LMWF-induced angiogenesis offer the opportunity for new therapeutic strategies of ischemic diseases. PMID:26516869

  10. Structural and functional characterization of the interaction between cyclophilin B and a heparin-derived oligosaccharide.

    PubMed

    Hanoulle, Xavier; Melchior, Aurélie; Sibille, Nathalie; Parent, Benjamin; Denys, Agnès; Wieruszeski, Jean-Michel; Horvath, Dragos; Allain, Fabrice; Lippens, Guy; Landrieu, Isabelle

    2007-11-23

    The chemotaxis and integrin-mediated adhesion of T lymphocytes triggered by secreted cyclophilin B (CypB) depend on interactions with both cell surface heparan sulfate proteoglycans (HSPG) and the extracellular domain of the CD147 membrane receptor. Here, we use NMR spectroscopy to characterize the interaction of CypB with heparin-derived oligosaccharides. Chemical shift perturbation experiments allowed the precise definition of the heparan sulfate (HS) binding site of CypB. The N-terminal extremity of CypB, which contains a consensus sequence for heparin-binding proteins was modeled on the basis of our experimental NMR data. Because the HS binding site extends toward the CypB catalytic pocket, we measured its peptidyl-prolyl cis-trans isomerase (PPIase) activity in the absence or presence of a HS oligosaccharide toward a CD147-derived peptide. We report the first direct evidence that CypB is enzymatically active on CD147, as it is able to accelerate the cis/trans isomerization of the Asp(179)-Pro(180) bond in a CD147-derived peptide. However, HS binding has no significant influence on this PPIase activity. We thus conclude that the glycanic moiety of HSPG serves as anchor for CypB at the cell surface, and that the signal could be transduced by CypB via its PPIase activity toward CD147.

  11. The role of heparins and nano-heparins as therapeutic tool in breast cancer.

    PubMed

    Afratis, Nikos A; Karamanou, Konstantina; Piperigkou, Zoi; Vynios, Demitrios H; Theocharis, Achilleas D

    2017-06-01

    Glycosaminoglycans are integral part of the dynamic extracellular matrix (ECM) network that control crucial biochemical and biomechanical signals required for tissue morphogenesis, differentiation, homeostasis and cancer development. Breast cancer cells communicate with stromal ones to modulate ECM mainly through release of soluble effectors during cancer progression. The intracellular cross-talk between cell surface receptors and estrogen receptors is important for the regulation of breast cancer cell properties and production of ECM molecules. In turn, reorganized ECM-cell surface interface modulates signaling cascades, which regulate almost all aspects of breast cell behavior. Heparan sulfate chains present on cell surface and matrix proteoglycans are involved in regulation of breast cancer functions since they are capable of binding numerous matrix molecules, growth factors and inflammatory mediators thus modulating their signaling. In addition to its anticoagulant activity, there is accumulating evidence highlighting various anticancer activities of heparin and nano-heparin derivatives in numerous types of cancer. Importantly, heparin derivatives significantly reduce breast cancer cell proliferation and metastasis in vitro and in vivo models as well as regulates the expression profile of major ECM macromolecules, providing strong evidence for therapeutic targeting. Nano-formulations of the glycosaminoglycan heparin are possibly novel tools for targeting tumor microenvironment. In this review, the role of heparan sulfate/heparin and its nano-formulations in breast cancer biology are presented and discussed in terms of future pharmacological targeting.

  12. Nucleolin is a nuclear target of heparan sulfate derived from glypican-1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cheng, Fang; Belting, Mattias; Fransson, Lars-Åke

    The recycling, S-nitrosylated heparan sulfate (HS) proteoglycan glypican-1 releases anhydromannose (anMan)-containing HS chains by a nitrosothiol-catalyzed cleavage in endosomes that can be constitutive or induced by ascorbate. The HS-anMan chains are then transported to the nucleus. A specific nuclear target for HS-anMan has not been identified. We have monitored endosome-to-nucleus trafficking of HS-anMan by deconvolution and confocal immunofluorescence microscopy using an anMan-specific monoclonal antibody in non-growing, ascorbate-treated, and growing, untreated, wild-type mouse embryonic fibroblasts and hypoxia-exposed Alzheimer mouse Tg2576 fibroblasts and human U87 glioblastoma cells. In all cells, nuclear HS-anMan targeted a limited number of sites of variable size wheremore » it colocalized with DNA and nucleolin, an established marker for nucleoli. HS-anMan also colocalized with ethynyl uridine-tagged nascent RNA and two acetylated forms of histone H3. Acute hypoxia increased the formation of HS-anMan in both Tg2576 and U87 cells. A portion of HS-anMan colocalized with nucleolin at small discrete sites, while most of the nucleolin and nascent RNA was dispersed. In U87 cells, HS-anMan, nucleolin and nascent RNA reassembled after prolonged hypoxia. Nucleolar HS may modulate synthesis and/or release of rRNA.« less

  13. Elevation of a collagenase generated type II collagen neoepitope and proteoglycan epitopes in synovial fluid following induction of joint instability in the dog

    PubMed Central

    Chu, Q.; Lopez, M.; Hayashi, K.; lonescu, M.; Billinghurst, R. C.; Johnson, K. A.; Poole, A. R.; Markel, M. D.

    2007-01-01

    Summary Clinical relevance Measurement of markers of cartilage pathology in synovial fluid may provide clinical rheumatologists and osteoarthritis (OA) researchers important information for early diagnosis of OA as well as a method for monitoring disease progression and response to treatment. This study demonstrates the value of this approach in an established model of OA (cranial cruciate ligament rupture) at a point distant enough from the original surgical manipulation so as to have little to no effect on the marker concentrations. Objective The objective of this study was to determine whether measurement of markers of cartilage collagen cleavage and proteoglycan turnover in synovial fluid from a canine model could be used to detect cartilage changes following the onset of joint instability during the development of OA. Design A model of joint instability that develops OA was created in 18 mature dogs using monopolar radiofrequency energy (MRFE). MRFE was arthroscopically applied to one cranial cruciate ligament (CCL) while the contralateral CCL was sham treated. The treated CCLs ruptured approximately 8 weeks (55 ± 1.6 days) after MRFE treatment. Synovial fluid was collected at time zero prior to MRFE treatment, 4 weeks after MRFE treatment, and at 4, 8, and 16 weeks after CCL rupture. Synovial fluid concentrations of the neoepitope COL2-3/4C long (type II collagen cleavage by collagenase) and epitopes 3B3(–) (proteoglycan aggrecan sulfation) and 846 (associated with aggrecan synthesis) were analyzed. Results Compared to sham treated joints, the synovial fluid concentrations of COL2-3/4C long and 3B3(–) were significantly increased 2.2 fold and 2.9 fold, respectively, in joints with MRFE treated CCLs following CCL rupture. Concentrations of the 846 epitope in synovial fluid showed a trend toward an increase, which was not significant, after CCL rupture. Conclusions Concentrations of the collagenase-cleaved type II collagen neoepitope and 3B3(–) epitope in synovial fluid were significantly increased by 4 weeks and remained elevated for at least 16 weeks after CCL rupture. This suggests that in dogs the COL2-3/4C long neoepitope and 3B3(–) epitope are sensitive markers for changes in joint cartilage turnover in joints that are developing OA. PMID:12479389

  14. Elevation of a collagenase generated type II collagen neoepitope and proteoglycan epitopes in synovial fluid following induction of joint instability in the dog.

    PubMed

    Chu, Q; Lopez, M; Hayashi, K; Ionescu, M; Billinghurst, R C; Johnson, K A; Poole, A R; Markel, M D

    2002-08-01

    Measurement of markers of cartilage pathology in synovial fluid may provide clinical rheumatologists and osteoarthritis (OA) researchers important information for early diagnosis of OA as well as a method for monitoring disease progression and response to treatment. This study demonstrates the value of this approach in an established model of OA (cranial cruciate ligament rupture) at a point distant enough from the original surgical manipulation so as to have little to no effect on the marker concentrations. The objective of this study was to determine whether measurement of markers of cartilage collagen cleavage and proteoglycan turnover in synovial fluid from a canine model could be used to detect cartilage changes following the onset of joint instability during the development of OA. A model of joint instability that develops OA was created in 18 mature dogs using monopolar radiofrequency energy (MRFE). MRFE was arthroscopically applied to one cranial cruciate ligament (CCL) while the contralateral CCL was sham treated. The treated CCLs ruptured approximately 8 weeks (55 +/- 1.6 days) after MRFE treatment. Synovial fluid was collected at time zero prior to MRFE treatment, 4 weeks after MRFE treatment, and at 4, 8, and 16 weeks after CCL rupture. Synovial fluid concentrations of the neoepitope COL2-3/4C long (type II collagen cleavage by collagenase) and epitopes 3B3(-) (proteoglycan aggrecan sulfation) and 846 (associated with aggrecan synthesis) were analyzed. Compared to sham treated joints, the synovial fluid concentrations of COL2-3/4C long and 3B3(-) were significantly increased 2.2 fold and 2.9 fold, respectively, in joints with MRFE treated CCLs following CCL rupture. Concentrations of the 846 epitope in synovial fluid showed a trend toward an increase, which was not significant, after CCL rupture. Concentrations of the collagenase-cleaved type II collagen neoepitope and 3B3(-) epitope in synovial fluid were significantly increased by 4 weeks and remained elevated for at least 16 weeks after CCL rupture. This suggests that in dogs the COL2-3/4C long neoepitope and 3B3(-) epitope are sensitive markers for changes in joint cartilage turnover in joints that are developing OA.

  15. Interactions between meniscal cells and a self assembled biomimetic surface composed of hyaluronic acid, chitosan and meniscal extracellular matrix molecules.

    PubMed

    Tan, Guak-Kim; Dinnes, Donna L M; Butler, Lauren N; Cooper-White, Justin J

    2010-08-01

    Menisci are one of the most commonly injured parts of the knee with a limited healing potential. This study focuses on fabrication and characterization of biomimetic surfaces for meniscal tissue engineering. To achieve this, a combination of hyaluronic acid/chitosan (HA/CH) mutilayers with covalently immobilized major extracellular matrix (ECM) components of native meniscus, namely collagen I/II (COL.I/II) and chondroitin-6-sulfate (C6S) was employed. Adsorption of the biomolecules was monitored using a quartz crystal microbalance with dissipation (QCM-D) and fourier transform-surface plasmon resonance (FT-SPR). Immobilization of the biomolecules onto HA/CH mutilayers was achieved by sequential adsorption, with optimum binding at a molar ratio of 1.4:1 (COL.I/II: C6S). After adding COL.I/II, the layers became relatively more rigid and large aggregates were evident. The effects of the modified surfaces on cell proliferation, gene expression and proteoglycan production of rat meniscal cells were examined. Quantitative real-time reverse transcriptase polymerase chain reaction (RT-qPCR) analysis showed that primary meniscal cells dedifferentiated rapidly after one passage in monolayer culture. This process could be reversed by culturing the cells on C6S surfaces, as indicated by increases in both collagen II and aggrecan gene expression, as well as proteoglycan production. Cells with abundant lipid vacuoles were evident on all the surfaces over an extended culture period. The results demonstrate the feasibility of C6S surfaces to avoid the dedifferentiation that normally occurs during monolayer expansion of meniscal cells. Crown Copyright 2010. Published by Elsevier Ltd. All rights reserved.

  16. The role of microtubules in the regulation of proteoglycan synthesis in chondrocytes under hydrostatic pressure.

    PubMed

    Jortikka, M O; Parkkinen, J J; Inkinen, R I; Kärner, J; Järveläinen, H T; Nelimarkka, L O; Tammi, M I; Lammi, M J

    2000-02-15

    Chondrocytes of the articular cartilage sense mechanical factors associated with joint loading, such as hydrostatic pressure, and maintain the homeostasis of the extracellular matrix by regulating the metabolism of proteoglycans (PGs) and collagens. Intermittent hydrostatic pressure stimulates, while continuous high hydrostatic pressure inhibits, the biosynthesis of PGs. High continuous hydrostatic pressure also changes the structure of cytoskeleton and Golgi complex in cultured chondrocytes. Using microtubule (MT)-affecting drugs nocodazole and taxol as tools we examined whether MTs are involved in the regulation of PG synthesis in pressurized primary chondrocyte monolayer cultures. Disruption of the microtubular array by nocodazole inhibited [(35)S]sulfate incorporation by 39-48%, while MT stabilization by taxol caused maximally a 17% inhibition. Continuous hydrostatic pressure further decreased the synthesis by 34-42% in nocodazole-treated cultures. This suggests that high pressure exerts its inhibitory effect through mechanisms independent of MTs. On the other hand, nocodazole and taxol both prevented the stimulation of PG synthesis by cyclic 0. 5 Hz, 5 MPa hydrostatic pressure. The drugs did not affect the structural and functional properties of the PGs, and none of the treatments significantly affected cell viability, as indicated by the high level of PG synthesis 24-48 h after the release of drugs and/or high hydrostatic pressure. Our data on two-dimensional chondrocyte cultures indicate that inhibition of PG synthesis by continuous high hydrostatic pressure does not interfere with the MT-dependent vesicle traffic, while the stimulation of synthesis by cyclic pressure does not occur if the dynamic nature of MTs is disturbed by nocodazole. Similar phenomena may operate in cartilage matrix embedded chondrocytes. Copyright 2000 Academic Press.

  17. Syndecan-2 is upregulated in colorectal cancer cells through interactions with extracellular matrix produced by stromal fibroblasts.

    PubMed

    Vicente, Carolina Meloni; Ricci, Ritchelli; Nader, Helena Bonciani; Toma, Leny

    2013-05-25

    The extracellular matrix (ECM) influences the structure, viability and functions of cells and tissues. Recent evidence indicates that tumor cells and stromal cells interact through direct cell-cell contact, the production of ECM components and the secretion of growth factors. Syndecans are a family of transmembrane heparan sulfate proteoglycans that are involved in cell adhesion, motility, proliferation and differentiation. Syndecan-2 has been found to be highly expressed in colorectal cancer cell lines and appears to be critical for cancer cell behavior. We have examined the effect of stromal fibroblast-produced ECM on the production of proteoglycans by colorectal cancer cell lines. Our results showed that in a highly metastatic colorectal cancer cell line, HCT-116, syndecan-2 expression is enhanced by fibroblast ECM, while the expression of other syndecans decreased. Of the various components of the stromal ECM, fibronectin was the most important in stimulating the increase in syndecan-2 expression. The co-localization of syndecan-2 and fibronectin suggests that these two molecules are involved in the adhesion of HCT-116 cells to the ECM. Additionally, we demonstrated an increase in the expression of integrins alpha-2 and beta-1, in addition to an increase in the expression of phospho-FAK in the presence of fibroblast ECM. Furthermore, blocking syndecan-2 with a specific antibody resulted in a decrease in cell adhesion, migration, and organization of actin filaments. Overall, these results show that interactions between cancer cells and stromal ECM proteins induce significant changes in the behavior of cancer cells. In particular, a shift from the expression of anti-tumorigenic syndecans to the tumorigenic syndecan-2 may have implications in the migratory behavior of highly metastatic tumor cells.

  18. Choroidal retinoic acid synthesis: a possible mediator between refractive error and compensatory eye growth.

    PubMed

    Mertz, J R; Wallman, J

    2000-04-01

    Research over the past two decades has shown that the growth of young eyes is guided by vision. If near- or far-sightedness is artificially imposed by spectacle lenses, eyes of primates and chicks compensate by changing their rate of elongation, thereby growing back to the pre-lens optical condition. Little is known about what chemical signals might mediate between visual effects on the retina and alterations of eye growth. We present five findings that point to choroidal retinoic acid possibly being such a mediator. First, the chick choroid can convert retinol into all-trans-retinoic acid at the rate of 11 +/- 3 pmoles mg protein(-1) hr(-1), compared to 1.3 +/- 0.3 for retina/RPE and no conversion for sclera. Second, those visual conditions that cause increased rates of ocular elongation (diffusers or negative lens wear) produce a sharp decrease in all-trans-retinoic acid synthesis to levels barely detectable with our assay. In contrast, visual conditions which result in decreased rates of ocular elongation (recovery from diffusers or positive lens wear) produce a four- to five-fold increase in the formation of all-trans-retinoic acid. Third, the choroidal retinoic acid is found bound to a 28-32 kD protein. Fourth, a large fraction of the choroidal retinoic acid synthesized in culture is found in a nucleus-enriched fraction of sclera. Finally, application of retinoic acid to cultured sclera at physiological concentrations produced an inhibition of proteoglycan production (as assessed by measuring sulfate incorporation) with a EC50 of 8 x 10(-7) M. These results show that the synthesis of choroidal retinoic acid is modulated by those visual manipulations that influence ocular elongation and that this retinoic acid may reach the sclera in concentrations adequate to modulate scleral proteoglycan formation.

  19. Altered synaptic marker abundance in the hippocampal stratum oriens of Ts65Dn mice is associated with exuberant expression of versican

    PubMed Central

    Howell, Matthew D; Gottschall, Paul E

    2012-01-01

    DS (Down syndrome), resulting from trisomy of chromosome 21, is the most common cause of genetic mental retardation; however, the molecular mechanisms underlying the cognitive deficits are poorly understood. Growing data indicate that changes in abundance or type of CSPGs (chondroitin sulfate proteoglycans) in the ECM (extracellular matrix) can influence synaptic structure and plasticity. The purpose of this study was to identify changes in synaptic structure in the hippocampus in a model of DS, the Ts65Dn mouse, and to determine the relationship to proteoglycan abundance and/or cleavage and cognitive disability. We measured synaptic proteins by ELISA and changes in lectican expression and processing in the hippocampus of young and old Ts65Dn mice and LMCs (littermate controls). In young (5 months old) Ts65Dn hippocampal extracts, we found a significant increase in the postsynaptic protein PSD-95 (postsynaptic density 95) compared with LMCs. In aged (20 months old) Ts65Dn hippocampus, this increase was localized to hippocampal stratum oriens extracts compared with LMCs. Aged Ts65Dn mice exhibited impaired hippocampal-dependent spatial learning and memory in the RAWM (radial-arm water maze) and a marked increase in levels of the lectican versican V2 in stratum oriens that correlated with the number of errors made in the final RAWM block. Ts65Dn stratum oriens PNNs (perineuronal nets), an extension of the ECM enveloping mostly inhibitory interneurons, were dispersed over a larger area compared with LMC mice. Taken together, these data suggest a possible association with alterations in the ECM and inhibitory neurotransmission in the Ts65Dn hippocampus which could contribute to cognitive deficits. PMID:22225533

  20. Nature of the interaction of chondroitin 4-sulphate and chondroitin sulphate–proteoglycan with collagen

    PubMed Central

    Öbrink, Björn; Wasteson, Åke

    1971-01-01

    The electrostatic interaction of chondroitin sulphate and the chondroitin sulphate–proteoglycan with collagen was studied by chromatography of the glycosaminoglycan and the proteoglycan on a collagen gel. The observed binding between the macromolecules increased with decreasing pH and ionic strength, and was significant under physiological conditions. A study of the interaction between chondroitin sulphate and a preparation of soluble collagen, with a partition-equilibrium technique, afforded similar results. PMID:4256063

  1. Salubrinal inhibits the expression of proteoglycans and favors neurite outgrowth from cortical neurons in vitro.

    PubMed

    Barreda-Manso, M Asunción; Yanguas-Casás, Natalia; Nieto-Sampedro, Manuel; Romero-Ramírez, Lorenzo

    2015-07-01

    After CNS injury, astrocytes and mesenchymal cells attempt to restore the disrupted glia limitans by secreting proteoglycans and extracellular matrix proteins (ECMs), forming the so-called glial scar. Although the glial scar is important in sealing the lesion, it is also a physical and functional barrier that prevents axonal regeneration. The synthesis of secretory proteins in the RER is under the control of the initiation factor of translation eIF2α. Inhibiting the synthesis of secretory proteins by increasing the phosphorylation of eIF2α, might be a pharmacologically efficient way of reducing proteoglycans and other profibrotic proteins present in the glial scar. Salubrinal, a neuroprotective drug, decreased the expression and secretion of proteoglycans and other profibrotic proteins induced by EGF or TGFβ, maintaining eIF2α phosphorylated. Besides, Salubrinal also reduced the transcription of proteoglycans and other profibrotic proteins, suggesting that it induced the degradation of non-translated mRNA. In a model in vitro of the glial scar, cortical neurons grown on cocultures of astrocytes and fibroblasts with TGFβ treated with Salubrinal, showed increased neurite outgrowth compared to untreated cells. Our results suggest that Salubrinal may be considered of therapeutic value facilitating axonal regeneration, by reducing overproduction and secretion of proteoglycans and profibrotic protein inhibitors of axonal growth. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Infection of Hepatocytes With HCV Increases Cell Surface Levels of Heparan Sulfate Proteoglycans, Uptake of Cholesterol and Lipoprotein, and Virus Entry by Up-regulating SMAD6 and SMAD7.

    PubMed

    Zhang, Fang; Sodroski, Catherine; Cha, Helen; Li, Qisheng; Liang, T Jake

    2017-01-01

    The signaling molecule and transcriptional regulator SMAD6, which inhibits the transforming growth factor β signaling pathway, is required for infection of hepatocytes by hepatitis C virus (HCV). We investigated the mechanisms by which SMAD6 and another inhibitory SMAD (SMAD7) promote HCV infection in human hepatoma cells and hepatocytes. We infected Huh7 and Huh7.5.1 cells and primary human hepatocytes with Japanese fulminant hepatitis-1 (JFH1) HCV cell culture system (HCVcc). We then measured HCV binding, intracellular levels of HCV RNA, and expression of target genes. We examined HCV entry in HepG2/microRNA (miR) 122/CD81 cells, which support entry and replication of HCV, were transfected these cells with small interfering RNAs targeting inhibitory SMADs to analyze gene expression profiles. Uptake of labeled low-density lipoprotein (LDL) and cholesterol was measured. Cell surface proteins were quantified by flow cytometry. We obtained liver biopsy samples from 69 patients with chronic HCV infection and 19 uninfected individuals (controls) and measured levels of syndecan 1 (SDC1), SMAD7, and SMAD6 messenger RNAs (mRNAs). Small interfering RNA knockdown of SMAD6 blocked the binding and infection of hepatoma cell lines and primary human hepatocytes by HCV, whereas SMAD6 overexpression increased HCV infection. We found levels of mRNAs encoding heparan sulfate proteoglycans (HSPGs), particularly SDC1 mRNA, and cell surface levels of heparan sulfate to be reduced in cells after SMAD6 knockdown. SMAD6 knockdown also reduced transcription of genes encoding lipoprotein and cholesterol uptake receptors, including the LDL receptor (LDLR), the very LDLR, and the scavenger receptor class B member 1 in hepatocytes; knockdown of SMAD6 also inhibited cell uptake of cholesterol and lipoprotein. Overexpression of SMAD6 increased the expression of these genes. Similar effects were observed with knockdown and overexpression of SMAD7. In addition, HCV infection of cells increased the expression of SMAD6, which required the activity of nuclear factor-κB, but not transforming growth factor β. Liver tissues from patients with chronic HCV infection had significantly higher levels of SMAD6, SMAD7, and HSPG mRNAs than controls. In studies of hepatoma cell lines and primary human hepatocytes, we found that infection with HCV leads to activation of nuclear factor-κB, resulting in increased expression of SMAD6 and SMAD7. Up-regulation of SMAD6 and SMAD7 induces the expression of HSPGs, such as SDC1, as well as LDLR, very LDLR, and the scavenger receptor class B member 1, which promote HCV entry and propagation, as well as cellular uptake of cholesterol and lipoprotein. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

  3. Targeting Common but Complex Proteoglycans on Breast Cancer Cells and Stem Cells Using Evolutionary Refined Malaria Proteins

    DTIC Science & Technology

    2015-11-01

    AWARD NUMBER: W81XWH-13-1-0139 TITLE: Targeting Common but Complex Proteoglycans on Breast Cancer Cells and Stem Cells Using Evolutionary Refined...DATES COVERED 15Aug2013 - 14Aug2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER W81XWH-13-1-0139 Targeting Common but Complex Proteoglycans on...outbreaks in epidemic regions of the world. Prior to this application we discovered that human breast cancer cells express this same carbohydrate

  4. Changes in collagen fibril network organization and proteoglycan distribution in equine articular cartilage during maturation and growth

    PubMed Central

    Hyttinen, Mika M; Holopainen, Jaakko; René van Weeren, P; Firth, Elwyn C; Helminen, Heikki J; Brama, Pieter A J

    2009-01-01

    The aim of this study was to record growth-related changes in collagen network organization and proteoglycan distribution in intermittently peak-loaded and continuously lower-level-loaded articular cartilage. Cartilage from the proximal phalangeal bone of the equine metacarpophalangeal joint at birth, at 5, 11 and 18 months, and at 6–10 years of age was collected from two sites. Site 1, at the joint margin, is unloaded at slow gaits but is subjected to high-intensity loading during athletic activity; site 2 is a continuously but less intensively loaded site in the centre of the joint. The degree of collagen parallelism was determined with quantitative polarized light microscopy and the parallelism index for collagen fibrils was computed from the cartilage surface to the osteochondral junction. Concurrent changes in the proteoglycan distribution were quantified with digital densitometry. We found that the parallelism index increased significantly with age (up to 90%). At birth, site 2 exhibited a more organized collagen network than site 1. In adult horses this situation was reversed. The superficial and intermediate zones exhibited the greatest reorganization of collagen. Site 1 had a higher proteoglycan content than site 2 at birth but here too the situation was reversed in adult horses. We conclude that large changes in joint loading during growth and maturation in the period from birth to adulthood profoundly affect the architecture of the collagen network in equine cartilage. In addition, the distribution and content of proteoglycans are modified significantly by altered joint use. Intermittent peak-loading with shear seems to induce higher collagen parallelism and a lower proteoglycan content in cartilage than more constant weight-bearing. Therefore, we hypothesize that the formation of mature articular cartilage with a highly parallel collagen network and relatively low proteoglycan content in the peak-loaded area of a joint is needed to withstand intermittent stress and shear, whereas a constantly weight-bearing joint area benefits from lower collagen parallelism and a higher proteoglycan content. PMID:19732210

  5. Collagen-Proteoglycan Relationships in Epiphyseal Cartilage

    PubMed Central

    Eisenstein, Reuben; Larsson, Sven-Erik; Sorgente, Nino; Kuettner, Klaus E.

    1973-01-01

    Columnar and hypertrophic zones of calf scapular cartilage were studied before and after extraction with 3 M guanidinium chloride (GuCl) and digestion with enzymes which degrade various components of the extracellular matrix. Morphologic and chemical analysis suggests that there are at least two anatomic pools of proteoglycan in this tissue. One, which resides between collagen fibrils, is extractable with GuCl. Another appears attached to collagen by strong bonds and is apparently not extractable with GuCl. This type of collagen-proteoglycan relationship is possibly restricted to epiphyseal cartilage. The morphology of the lacuna is different in the columnar and hypertrophic zones. Proteoglycans in the distal hypertrophic zone are less resistant to GuCl extraction. ImagesFig 9Fig 10Fig 11Fig 1Fig 2Fig 3Fig 4Fig 5Fig 6Fig 7Fig 8 PMID:4357177

  6. Evaluation of the effect of antiarthritic drugs on the secretion of proteoglycans by lapine chondrocytes using a novel assay procedure.

    PubMed Central

    Collier, S; Ghosh, P

    1989-01-01

    A new method is described for separating free 35SO4-- from 35SO4 labelled proteoglycans synthesised by rabbit articular chondrocytes cultured in the presence of excess 35SO4--. The procedure uses the low solubility product of barium sulphate to remove, by precipitation, free 35SO4-- from culture medium. Optimum recovery of 35SO4 labelled proteoglycans was achieved after papain digestion to release 35SO4-glycosaminoglycans, and addition of chondroitin sulphate before the precipitation step. Using this assay, we studied the effect of six drugs-indomethacin, diclofenac, sodium pentosan polysulphate, glycosaminoglycan polysulphate ester, tiaprofenic acid, and ketoprofen-on the secretion into the medium of labelled proteoglycans by lapine chondrocytes. The six drugs were tested at 0.1, 1, 10, 50, and 100 micrograms/ml over four consecutive 48 hour culture periods. A consistent concentration-response pattern was found for the four non-steroidal anti-inflammatory drugs (NSAIDs) studied. Generally they inhibited proteoglycan secretion at 50 and 100 micrograms/ml but had no effect at lower concentrations. Inhibition of secretion was strongest with indomethacin and diclofenac at 50 and 100 micrograms/ml. In contrast with the NSAIDs studied, the two sulphated polysaccharides (sodium pentosan polysulphate and glycosaminoglycan polysulphate ester) at low concentrations increased proteoglycan secretion by chondrocytes, with maximal stimulation occurring at 1 microgram/ml. Sodium pentosan polysulphate, but not glycosaminoglycan polysulphate ester, showed inhibitory activity at 50 and 100 micrograms/ml. PMID:2471470

  7. SomethiNG 2 talk about-Transcriptional regulation in embryonic and adult oligodendrocyte precursors.

    PubMed

    Küspert, Melanie; Wegner, Michael

    2016-05-01

    Glial cells that express the chondroitin sulfate proteoglycan NG2 represent an inherently heterogeneous population. These so-called NG2-glia are present during development and in the adult CNS, where they are referred to as embryonic oligodendrocyte precursors and adult NG2-glia, respectively. They give rise to myelinating oligodendrocytes at all times of life. Over the years much has been learnt about the transcriptional network in embryonic oligodendrocyte precursors, and several transcription factors from the HLH, HMG-domain, zinc finger and homeodomain protein families have been identified as main constituents. Much less is known about the corresponding network in adult NG2-glia. Here we summarize and discuss current knowledge on functions of each of these transcription factor families in NG2-glia, and where possible compare transcriptional regulation in embryonic oligodendrocyte precursors and adult NG2-glia. This article is part of a Special Issue entitled SI:NG2-glia (Invited only). Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Syndecan defines precise spindle orientation by modulating Wnt signaling in C. elegans.

    PubMed

    Dejima, Katsufumi; Kang, Sukryool; Mitani, Shohei; Cosman, Pamela C; Chisholm, Andrew D

    2014-11-01

    Wnt signals orient mitotic spindles in development, but it remains unclear how Wnt signaling is spatially controlled to achieve precise spindle orientation. Here, we show that C. elegans syndecan (SDN-1) is required for precise orientation of a mitotic spindle in response to a Wnt cue. We find that SDN-1 is the predominant heparan sulfate (HS) proteoglycan in the early C. elegans embryo, and that loss of HS biosynthesis or of the SDN-1 core protein results in misorientation of the spindle of the ABar blastomere. The ABar and EMS spindles both reorient in response to Wnt signals, but only ABar spindle reorientation is dependent on a new cell contact and on HS and SDN-1. SDN-1 transiently accumulates on the ABar surface as it contacts C, and is required for local concentration of Dishevelled (MIG-5) in the ABar cortex adjacent to C. These findings establish a new role for syndecan in Wnt-dependent spindle orientation. © 2014. Published by The Company of Biologists Ltd.

  9. The Caenorhabditis elegans Ephrin EFN-4 Functions Non-cell Autonomously with Heparan Sulfate Proteoglycans to Promote Axon Outgrowth and Branching

    PubMed Central

    Schwieterman, Alicia A.; Steves, Alyse N.; Yee, Vivian; Donelson, Cory J.; Bentley, Melissa R.; Santorella, Elise M.; Mehlenbacher, Taylor V.; Pital, Aaron; Howard, Austin M.; Wilson, Melissa R.; Ereddia, Danielle E.; Effrein, Kelsie S.; McMurry, Jonathan L.; Ackley, Brian D.; Chisholm, Andrew D.; Hudson, Martin L.

    2016-01-01

    The Eph receptors and their cognate ephrin ligands play key roles in many aspects of nervous system development. These interactions typically occur within an individual tissue type, serving either to guide axons to their terminal targets or to define boundaries between the rhombomeres of the hindbrain. We have identified a novel role for the Caenorhabditis elegans ephrin EFN-4 in promoting primary neurite outgrowth in AIY interneurons and D-class motor neurons. Rescue experiments reveal that EFN-4 functions non-cell autonomously in the epidermis to promote primary neurite outgrowth. We also find that EFN-4 plays a role in promoting ectopic axon branching in a C. elegans model of X-linked Kallmann syndrome. In this context, EFN-4 functions non-cell autonomously in the body-wall muscle and in parallel with HS modification genes and HSPG core proteins. This is the first report of an epidermal ephrin providing a developmental cue to the nervous system. PMID:26645816

  10. Craniofacial skeletal defects of adult zebrafish glypican 4 (knypek) mutants

    PubMed Central

    LeClair, Elizabeth E.; Mui, Stephanie R.; Huang, Angela; Topczewska, Jolanta M.; Topczewski, Jacek

    2010-01-01

    The heparan sulfate proteoglycan Glypican 4 (Gpc4) is part of the Wnt/planar cell polarity pathway, which is required for convergence and extension during zebrafish gastrulation. To observe Glypican 4-deficient phenotypes at later stages, we rescued gpc4−/− (knypek) homozygotes and raised them for more than one year. Adult mutants showed diverse cranial malformations of both dermal and endochondral bones, ranging from shortening of the rostral-most skull to loss of the symplectic. Additionally, the adult palatoquadrate cartilage was disorganized, with abnormal chondrocyte orientation. To understand how the palatoquadrate cartilage normally develops, we examined a juvenile series of wild type and mutant specimens. This identified two novel domains of elongated chondrocytes in the larval palatoquadrate, which normally form prior to endochondral ossification. In contrast, gpc4−/− larvae never form these domains, suggesting a failure of chondrocyte orientation, though not differentiation. Our findings implicate Gpc4 in the regulation of zebrafish cartilage and bone morphogenesis. PMID:19777561

  11. Identification of the heparin binding site on adeno-associated virus serotype 3B (AAV-3B)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lerch, Thomas F.; Chapman, Michael S., E-mail: chapmami@ohsu.edu

    2012-02-05

    Adeno-associated virus is a promising vector for gene therapy. In the current study, the binding site on AAV serotype 3B for the heparan sulfate proteoglycan (HSPG) receptor has been characterized. X-ray diffraction identified a disaccharide binding site at the most positively charged region on the virus surface. The contributions of basic amino acids at this and other sites were characterized using site-directed mutagenesis. Both heparin and cell binding are correlated to positive charge at the disaccharide binding site, and transduction is significantly decreased in AAV-3B vectors mutated at this site to reduce heparin binding. While the receptor attachment sites ofmore » AAV-3B and AAV-2 are both in the general vicinity of the viral spikes, the exact amino acids that participate in electrostatic interactions are distinct. Diversity in the mechanisms of cell attachment by AAV serotypes will be an important consideration for the rational design of improved gene therapy vectors.« less

  12. Identification of the heparin binding site on adeno-associated virus serotype 3B (AAV-3B)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lerch, Thomas F.; Chapman, Michael S.

    2012-05-24

    Adeno-associated virus is a promising vector for gene therapy. In the current study, the binding site on AAV serotype 3B for the heparan sulfate proteoglycan (HSPG) receptor has been characterized. X-ray diffraction identified a disaccharide binding site at the most positively charged region on the virus surface. The contributions of basic amino acids at this and other sites were characterized using site-directed mutagenesis. Both heparin and cell binding are correlated to positive charge at the disaccharide binding site, and transduction is significantly decreased in AAV-3B vectors mutated at this site to reduce heparin binding. While the receptor attachment sites ofmore » AAV-3B and AAV-2 are both in the general vicinity of the viral spikes, the exact amino acids that participate in electrostatic interactions are distinct. Diversity in the mechanisms of cell attachment by AAV serotypes will be an important consideration for the rational design of improved gene therapy vectors.« less

  13. Proliferative activity of elastin-like-peptides depends on charge and phase transition.

    PubMed

    Yuan, Yuan; Koria, Piyush

    2016-03-01

    Elastin-like-peptides (ELPs) are stimulus-responsive protein-based polymers and are attractive biomaterials due to their biocompatibility and unique properties. This study shows that in addition to their physical properties, ELPs have biological activities that are conducive to tissue regeneration. Specifically, we found that ELPs induce fibroblast proliferation via cell surface heparan sulfate proteoglycans (HSPG). Furthermore, our data suggests that ELP based materials with differential proliferative potential can be designed by controlling the interaction of ELPs with HSPGs by incorporating either hydrophobic or positively charged residues within the ELP sequence. Fibroblast proliferation is important for granulation tissue formation which is important in chronic wounds as well as in healing of other tissues. The customizable biological activity of ELPs coupled with their unique physical properties will enable us to design novel, sustainable and cost effective therapies for different tissue regeneration applications. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 697-706, 2016. © 2015 Wiley Periodicals, Inc.

  14. R-spondins can potentiate WNT signaling without LGRs.

    PubMed

    Lebensohn, Andres M; Rohatgi, Rajat

    2018-02-06

    The WNT signaling pathway regulates patterning and morphogenesis during development and promotes tissue renewal and regeneration in adults. The R-spondin (RSPO) family of four secreted proteins, RSPO1-4, amplifies target cell sensitivity to WNT ligands by increasing WNT receptor levels. Leucine-rich repeat-containing G-protein coupled receptors (LGRs) 4-6 are considered obligate high-affinity receptors for RSPOs. We discovered that RSPO2 and RSPO3, but not RSPO1 or RSPO4, can potentiate WNT/β-catenin signaling in the absence of all three LGRs. By mapping the domains on RSPO3 that are necessary and sufficient for this activity, we show that the requirement for LGRs is dictated by the interaction between RSPOs and the ZNRF3/RNF43 E3 ubiquitin ligases and that LGR-independent signaling depends on heparan sulfate proteoglycans (HSPGs). We propose that RSPOs can potentiate WNT signals through distinct mechanisms that differ in their use of either LGRs or HSPGs, with implications for understanding their biological functions. © 2017, Lebensohn et al.

  15. R-spondins can potentiate WNT signaling without LGRs

    PubMed Central

    2018-01-01

    The WNT signaling pathway regulates patterning and morphogenesis during development and promotes tissue renewal and regeneration in adults. The R-spondin (RSPO) family of four secreted proteins, RSPO1-4, amplifies target cell sensitivity to WNT ligands by increasing WNT receptor levels. Leucine-rich repeat-containing G-protein coupled receptors (LGRs) 4-6 are considered obligate high-affinity receptors for RSPOs. We discovered that RSPO2 and RSPO3, but not RSPO1 or RSPO4, can potentiate WNT/β-catenin signaling in the absence of all three LGRs. By mapping the domains on RSPO3 that are necessary and sufficient for this activity, we show that the requirement for LGRs is dictated by the interaction between RSPOs and the ZNRF3/RNF43 E3 ubiquitin ligases and that LGR-independent signaling depends on heparan sulfate proteoglycans (HSPGs). We propose that RSPOs can potentiate WNT signals through distinct mechanisms that differ in their use of either LGRs or HSPGs, with implications for understanding their biological functions. PMID:29405118

  16. NMR Studies of Cartilage Dynamics, Diffusion, Degradation

    NASA Astrophysics Data System (ADS)

    Huster, Daniel; Schiller, Jurgen; Naji, Lama; Kaufmann Jorn; Arnold, Klaus

    An increasing number of people is suffering from rheumatic diseases, and, therefore, methods of early diagnosis of joint degeneration are urgently required. For their establishment, however, an improved knowledge about the molecular organisation of cartilage would be helpful. Cartilage consists of three main components: Water, collagen and chondroitin sulfate (CS) that is (together with further polysaccharides and proteins) a major constituent of the proteoglycans of cartilage. 1H and 13C MAS (magic-angle spinning) NMR (nuclear magnetic resonance) opened new perspectives for the study of the macromolecular components in cartilage. We have primarily studied the mobilities of CS and collagen in bovine nasal and pig articular cartilage (that differ significantly in their collagen/polysaccharide content) by measuring 13C NMR relaxation times as well as the corresponding 13C CP (cross polarisation) MAS NMR spectra. These data clearly indicate that the mobility of cartilage macromolecules is broadly distributed from almost completely rigid (collagen) to highly mobile (polysaccharides), which lends cartilage its mechanical strength and shock-absorbing properties.

  17. Casting a Wide Net: Role of Perineuronal Nets in Neural Plasticity.

    PubMed

    Sorg, Barbara A; Berretta, Sabina; Blacktop, Jordan M; Fawcett, James W; Kitagawa, Hiroshi; Kwok, Jessica C F; Miquel, Marta

    2016-11-09

    Perineuronal nets (PNNs) are unique extracellular matrix structures that wrap around certain neurons in the CNS during development and control plasticity in the adult CNS. They appear to contribute to a wide range of diseases/disorders of the brain, are involved in recovery from spinal cord injury, and are altered during aging, learning and memory, and after exposure to drugs of abuse. Here the focus is on how a major component of PNNs, chondroitin sulfate proteoglycans, control plasticity, and on the role of PNNs in memory in normal aging, in a tauopathy model of Alzheimer's disease, and in drug addiction. Also discussed is how altered extracellular matrix/PNN formation during development may produce synaptic pathology associated with schizophrenia, bipolar disorder, major depression, and autism spectrum disorders. Understanding the molecular underpinnings of how PNNs are altered in normal physiology and disease will offer insights into new treatment approaches for these diseases. Copyright © 2016 the authors 0270-6474/16/3611459-10$15.00/0.

  18. Cell-free HTLV-1 infects dendritic cells leading to transmission and transformation of CD4(+) T cells.

    PubMed

    Jones, Kathryn S; Petrow-Sadowski, Cari; Huang, Ying K; Bertolette, Daniel C; Ruscetti, Francis W

    2008-04-01

    Cell-free human T-lymphotropic virus type 1 (HTLV-1) virions are poorly infectious in vitro for their primary target cells, CD4(+) T cells. Here, we show that HTLV-1 can efficiently infect myeloid and plasmacytoid dendritic cells (DCs). Moreover, DCs exposed to HTLV-1, both before and after being productively infected, can rapidly, efficiently and reproducibly transfer virus to autologous primary CD4(+) T cells. This DC-mediated transfer of HTLV-1 involves heparan sulfate proteoglycans and neuropilin-1 and results in long-term productive infection and interleukin-2-independent transformation of the CD4(+) T cells. These studies, along with observations of HTLV-1-infected DCs in the peripheral blood of infected individuals, indicate that DCs have a central role in HTLV-1 transmission, dissemination and persistence in vivo. In addition to altering the current paradigm concerning how HTLV-1 transmission occurs, these studies suggest that impairment of DC function after HTLV-1 infection plays a part in pathogenesis.

  19. Crystal Structure of the Frizzled-Like Cysteine-Rich Domain of the Receptor Tyrosine Kinase MuSK

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stiegler, A.; Burden, S; Hubbard, S

    Muscle-specific kinase (MuSK) is an essential receptor tyrosine kinase for the establishment and maintenance of the neuromuscular junction (NMJ). Activation of MuSK by agrin, a neuronally derived heparan-sulfate proteoglycan, and LRP4 (low-density lipoprotein receptor-related protein-4), the agrin receptor, leads to clustering of acetylcholine receptors on the postsynaptic side of the NMJ. The ectodomain of MuSK comprises three immunoglobulin-like domains and a cysteine-rich domain (Fz-CRD) related to those in Frizzled proteins, the receptors for Wnts. Here, we report the crystal structure of the MuSK Fz-CRD at 2.1 {angstrom} resolution. The structure reveals a five-disulfide-bridged domain similar to CRDs of Frizzled proteinsmore » but with a divergent C-terminal region. An asymmetric dimer present in the crystal structure implicates surface hydrophobic residues that may function in homotypic or heterotypic interactions to mediate co-clustering of MuSK, rapsyn, and acetylcholine receptors at the NMJ.« less

  20. In Sickness and in Health: Perineuronal Nets and Synaptic Plasticity in Psychiatric Disorders

    PubMed Central

    Pantazopoulos, Harry; Berretta, Sabina

    2016-01-01

    Rapidly emerging evidence implicates perineuronal nets (PNNs) and extracellular matrix (ECM) molecules that compose or interact with PNNs, in the pathophysiology of several psychiatric disorders. Studies on schizophrenia, autism spectrum disorders, mood disorders, Alzheimer's disease, and epilepsy point to the involvement of ECM molecules such as chondroitin sulfate proteoglycans, Reelin, and matrix metalloproteases, as well as their cell surface receptors. In many of these disorders, PNN abnormalities have also been reported. In the context of the “quadripartite” synapse concept, that is, the functional unit composed of the pre- and postsynaptic terminals, glial processes, and ECM, and of the role that PNNs and ECM molecules play in regulating synaptic functions and plasticity, these findings resonate with one of the most well-replicated aspects of the pathology of psychiatric disorders, that is, synaptic abnormalities. Here we review the evidence for PNN/ECM-related pathology in these disorders, with particular emphasis on schizophrenia, and discuss the hypothesis that such pathology may significantly contribute to synaptic dysfunction. PMID:26839720

  1. Identification and expression analysis of zebrafish glypicans during embryonic development.

    PubMed

    Gupta, Mansi; Brand, Michael

    2013-01-01

    Heparan sulfate Proteoglycans (HSPG) are ubiquitous molecules with indispensable functions in various biological processes. Glypicans are a family of HSPG's, characterized by a Gpi-anchor which directs them to the cell surface and/or extracellular matrix where they regulate growth factor signaling during development and disease. We report the identification and expression pattern of glypican genes from zebrafish. The zebrafish genome contains 10 glypican homologs, as opposed to six in mammals, which are highly conserved and are phylogenetically related to the mammalian genes. Some of the fish glypicans like Gpc1a, Gpc3, Gpc4, Gpc6a and Gpc6b show conserved synteny with their mammalian cognate genes. Many glypicans are expressed during the gastrulation stage, but their expression becomes more tissue specific and defined during somitogenesis stages, particularly in the developing central nervous system. Existence of multiple glypican orthologs in fish with diverse expression pattern suggests highly specialized and/or redundant function of these genes during embryonic development.

  2. An Attractive Reelin Gradient Establishes Synaptic Lamination in the Vertebrate Visual System.

    PubMed

    Di Donato, Vincenzo; De Santis, Flavia; Albadri, Shahad; Auer, Thomas Oliver; Duroure, Karine; Charpentier, Marine; Concordet, Jean-Paul; Gebhardt, Christoph; Del Bene, Filippo

    2018-03-07

    A conserved organizational and functional principle of neural networks is the segregation of axon-dendritic synaptic connections into laminae. Here we report that targeting of synaptic laminae by retinal ganglion cell (RGC) arbors in the vertebrate visual system is regulated by a signaling system relying on target-derived Reelin and VLDLR/Dab1a on the projecting neurons. Furthermore, we find that Reelin is distributed as a gradient on the target tissue and stabilized by heparan sulfate proteoglycans (HSPGs) in the extracellular matrix (ECM). Through genetic manipulations, we show that this Reelin gradient is important for laminar targeting and that it is attractive for RGC axons. Finally, we suggest a comprehensive model of synaptic lamina formation in which attractive Reelin counter-balances repulsive Slit1, thereby guiding RGC axons toward single synaptic laminae. We establish a mechanism that may represent a general principle for neural network assembly in vertebrate species and across different brain areas. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. Sonic hedgehog regulates its own receptor on postcrossing commissural axons in a glypican1-dependent manner.

    PubMed

    Wilson, Nicole H; Stoeckli, Esther T

    2013-08-07

    Upon reaching their intermediate target, the floorplate, commissural axons acquire responsiveness to repulsive guidance cues, allowing the axons to exit the midline and adopt a contralateral, longitudinal trajectory. The molecular mechanisms that regulate this switch from attraction to repulsion remain poorly defined. Here, we show that the heparan sulfate proteoglycan Glypican1 (GPC1) is required as a coreceptor for the Shh-dependent induction of Hedgehog-interacting protein (Hhip) in commissural neurons. In turn, Hhip is required for postcrossing axons to respond to a repulsive anteroposterior Shh gradient. Thus, Shh is a cue with dual function. In precrossing axons it acts as an attractive guidance molecule in a transcription-independent manner. At the same time, Shh binds to GPC1 to induce the expression of its own receptor, Hhip, which mediates the repulsive response of postcrossing axons to Shh. Our study characterizes a molecular mechanism by which navigating axons switch their responsiveness at intermediate targets. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Isolation and Purification of Versican and Analysis of Versican Proteolysis

    PubMed Central

    Foulcer, Simon J.; Day, Anthony J.; Apte, Suneel S.

    2017-01-01

    Versican is a widely distributed chondroitin sulfate proteoglycan that forms large complexes with the glycosaminoglycan hyaluronan (HA). As a consequence of HA binding to its receptor CD44 and interactions of the versican C-terminal globular (G3) domain with a variety of extracellular matrix proteins, versican is a key component of well-defined networks in pericellular matrix and extracellular matrix. It is crucial for several developmental processes in the embryo and there is increasing interest in its roles in cancer and inflammation. Versican proteolysis by ADAMTS proteases is highly regulated, occurs at specific peptide bonds, and is relevant to several physiological and disease mechanisms. In this chapter, methods are described for the isolation and detection of intact and cleaved versican in tissues using morphologic and biochemical techniques. These, together with the methodologies for purification and analysis of recombinant versican and a versican fragment provided here, are likely to facilitate further progress on the biology of versican and its proteolysis. PMID:25325983

  5. Isolation and purification of versican and analysis of versican proteolysis.

    PubMed

    Foulcer, Simon J; Day, Anthony J; Apte, Suneel S

    2015-01-01

    Versican is a widely distributed chondroitin sulfate proteoglycan that forms large complexes with the glycosaminoglycan hyaluronan (HA). As a consequence of HA binding to its receptor CD44 and interactions of the versican C-terminal globular (G3) domain with a variety of extracellular matrix proteins, versican is a key component of well-defined networks in pericellular matrix and extracellular matrix. It is crucial for several developmental processes in the embryo and there is increasing interest in its roles in cancer and inflammation. Versican proteolysis by ADAMTS proteases is highly regulated, occurs at specific peptide bonds, and is relevant to several physiological and disease mechanisms. In this chapter, methods are described for the isolation and detection of intact and cleaved versican in tissues using morphologic and biochemical techniques. These, together with the methodologies for purification and analysis of recombinant versican and a versican fragment provided here, are likely to facilitate further progress on the biology of versican and its proteolysis.

  6. Graded levels of FGF protein span the midbrain and can instruct graded induction and repression of neural mapping labels

    PubMed Central

    Chen, Yao; Mohammadi, Moosa; Flanagan, John G.

    2009-01-01

    Summary Graded guidance labels are widely used in neural map formation, but it is not well understood which potential strategy leads to their graded expression. In midbrain tectal map development, FGFs can induce an entire midbrain, but their protein distribution is unclear, nor is it known whether they may act instructively to produce graded gene expression. Using a receptor-alkaline phosphatase fusion probe, we find a long-range posterior>anterior FGF protein gradient spanning the midbrain. Heparan sulfate proteoglycan (HSPG) is required for this gradient. To test whether graded FGF concentrations can instruct graded gene expression, a quantitative tectal explant assay was developed. Engrailed-2 and ephrin-As, normally in posterior>anterior tectal gradients, showed graded upregulation. Moreover, EphAs, normally in anterior>posterior countergradients, showed coordinately graded downregulation. These results provide a mechanism to establish graded mapping labels, and more generally provide a developmental strategy to coordinately induce a structure and pattern its cell properties in gradients. PMID:19555646

  7. Occurrence and structural characterization of versican-like proteoglycan in human vitreous.

    PubMed

    Theocharis, Achilleas D; Papageorgakopoulou, Nickoletta; Feretis, Elias; Theocharis, Dimitrios A

    2002-12-01

    Human vitreous gel is a special type of extracellular matrix, in which interpenetrating networks of collagen fibrils and hyaluronan are found. In this study, we report that apart from significant amounts of collagen, hyaluronan and sialylated glycoproteins, it was found that the human vitreous gel also contained low amounts of versican-like proteoglycan. The concentration of versican-like proteoglycan in the whole vitreous is 0.06 mg protein/ml of vitreous gel and represents a small percentage (about 5%) of the total protein content. The versican-like proteoglycan has a molecular mass of 380 kDa, as estimated by gel chromatography. Its core protein is substituted by chondroitin sulphate side chains (average molecular weight 37 kDa), in which 6-sulphated disaccharides predominated. According to the physicochemical data, the number of chondroitin sulphate chains is likely to be 5-7 per molecule. These proteoglycan monomers form large aggregates with endogenous hyaluronan. Versican, which is able to bind lectins via its C-terminal region, may bridge or interconnect various constituents of the extracellular matrix via its terminal domains in order to stabilize large supramolecular complexes at the vitreous, contributing towards the integrity and specific properties of the tissue.

  8. Cell surface chondroitin sulfate glycosaminoglycan in melanoma: role in the activation of pro-MMP-2 (pro-gelatinase A)

    PubMed Central

    Iida, Joji; Wilhelmson, Krista L.; Ng, Janet; Lee, Peter; Morrison, Charlotte; Tam, Eric; Overall, Christopher M.; McCarthy, James B.

    2007-01-01

    We previously reported that CS (chondroitin sulfate) GAG (glycosaminoglycan), expressed on MCSP (melanoma-specific CS proteoglycan), is important for regulating MT3-MMP [membrane-type 3 MMP (matrix metalloproteinase)]-mediated human melanoma invasion and gelatinolytic activity in vitro. In the present study, we sought to determine if CS can directly enhance MT3-MMP-mediated activation of pro-MMP-2. Co-immunoprecipitation studies suggest that MCSP forms a complex with MT3-MMP and MMP-2 on melanoma cell surface. When melanoma cells were treated with βDX (p-nitro-β-D-xylopyranoside) to inhibit coupling of CS on the core protein, both active form and proform of MMP-2 were no longer co-immunoprecipitated with either MCSP or MT3-MMP, suggesting a model in which CS directly binds to MMP-2 and presents the gelatinase to MT3-MMP to be activated. By using recombinant proteins, we determined that MT3-MMP directly activates pro-MMP-2 and that this activation requires the interaction of the C-terminal domain of pro-MMP-2 with MT3-MMP. Activation of pro-MMP-2 by suboptimal concentrations of MT3-MMP is also significantly enhanced in the presence of excess C4S (chondroitin 4-sulfate), whereas C6S (chondroitin 6-sulfate) or low-molecular-mass hyaluronan was ineffective. Affinity chromatography studies using CS isolated from aggrecan indicate that the catalytic domain of MT3-MMP and the C-terminal domain of MMP-2 directly bind to the GAG. Thus the direct binding of pro-MMP-2 with CS through the C-domain would present the catalytic domain of pro-MMP-2 to MT3-MMP, which facilitates the generation of the active form of MMP-2. These results suggest that C4S, which is expressed on tumour cell surface, can function to bind to pro-MMP-2 and facilitate its activation by MT3-MMP-expressing tumour cells to enhance invasion and metastasis. PMID:17217338

  9. Heparin Oligosaccharides as Potential Therapeutic Agents in Senile Dementia

    PubMed Central

    Ma, Qing; Cornelli, Umberto; Hanin, Israel; Jeske, Walter P.; Linhardt, Robert J.; Walenga, Jeanine M.; Fareed, Jawed; Lee, John M.

    2014-01-01

    Heparin is a glycosaminoglycan mixture currently used in prophylaxis and treatment of thrombosis. Heparin possesses non-anticoagulant properties, including modulation of various proteases, interactions with fibroblast growth factors, and anti-inflammatory actions. Senile dementia of Alzheimer’s type is accompanied by inflammatory responses contributing to irreversible changes in neuronal viability and brain function. Vascular factors are also involved in the pathogenesis of senile dementia. Inflammation, endogenous proteoglycans, and assembly of senile plagues and neurofibrillary tangles contribute directly and indirectly to further neuronal damage. Neuron salvage can be achieved by anti-inflammation and the competitive inhibition of proteoglycans accumulation. The complexity of the pathology of senile dementia provides numerous potential targets for therapeutic interventions designed to modulate inflammation and proteoglycan assembly. Heparin and related oligosaccharides are known to exhibit anti-inflammatory effects as well as inhibitory effects on proteoglycan assembly and may prove useful as neuroprotective agents. PMID:17504153

  10. Dermatan sulphate-rich proteoglycan associates with rat tail-tendon collagen at the d band in the gap region.

    PubMed Central

    Scott, J E; Orford, C R

    1981-01-01

    Rat tail tendon was stained with a cationic phthalocyanin dye, Cupromeronic Blue, in a 'critical-electrolyte-concentration' method [Scott (1980) Biochem. J. 187, 887-891] specifically to demonstrate proteoglycan by electron microscopy. Hyaluronidase digestion in the presence of proteinase inhibitors corroborated the results. Collagen was stained with uranyl acetate and/or phosphotungstic acid to demonstrate the banding pattern a-e in the D period. Proteoglycan was distributed about the collagen fibrils in an orthogonal array, the transverse elements of which were located almost exclusively at the d band, in the gap zone. The proteoglycan may inhibit (1) fibril radial growth by accretion of collagen molecules or fibril fusion, through interference with cross-linking, and (2) calcification by occupying the holes in the gap region later to be filled with hydroxyapatite. Images PLATE 1 PMID:7317031

  11. Glycosaminoglycan-Mediated Downstream Signaling of CXCL8 Binding to Endothelial Cells

    PubMed Central

    Derler, Rupert; Weber, Corinna; Strutzmann, Elisabeth; Miller, Ingrid; Kungl, Andreas

    2017-01-01

    The recruitment of leukocytes, mediated by endothelium bound chemokine gradients, is a vital process in inflammation. The highly negatively charged, unbranched polysaccharide family of glycosaminoglycans (GAGs), such as heparan sulfate and chondroitin sulfate mediate chemokine immobilization. Specifically the binding of CXCL8 (interleukin 8) to GAGs on endothelial cell surfaces is known to regulate neutrophil recruitment. Currently, it is not clear if binding of CXCL8 to GAGs leads to endothelial downstream signaling in addition to the typical CXCR1/CXCR2 (C-X-C motif chemokine receptor 1 and 2)-mediated signaling which activates neutrophils. Here we have investigated the changes in protein expression of human microvascular endothelial cells induced by CXCL8. Tumor necrosis factor alpha (TNFα) stimulation was used to mimic an inflammatory state which allowed us to identify syndecan-4 (SDC4) as the potential proteoglycan co-receptor of CXCL8 by gene array, real-time PCR and flow cytometry experiments. Enzymatic GAG depolymerization via heparinase III and chondroitinase ABC was used to emulate the effect of glycocalyx remodeling on CXCL8-induced endothelial downstream signaling. Proteomic analyses showed changes in the expression pattern of a number of endothelial proteins such as Zyxin and Caldesmon involved in cytoskeletal organization, cell adhesion and cell mobility. These results demonstrate for the first time a potential role of GAG-mediated endothelial downstream signaling in addition to the well-known CXCL8-CXCR1/CXCR2 signaling pathways in neutrophils. PMID:29207576

  12. DcR3 binds to ovarian cancer via heparan sulfate proteoglycans and modulates tumor cells response to platinum with corresponding alteration in the expression of BRCA1

    PubMed Central

    2012-01-01

    Background Overcoming platinum resistance is a major obstacle in the treatment of Epithelial Ovarian Cancer (EOC). In our previous work Decoy Receptor 3 (DcR3) was found to be related to platinum resistance. The major objective of this work was to define the cellular interaction of DcR3 with EOC and to explore its effects on platinum responsiveness. Methods We studied cell lines and primary cultures for the expression of and the cells ability to bind DcR3. Cells were cultured with DcR3 and then exposed to platinum. Cell viability was determined by MTT assay. Finally, the cells molecular response to DcR3 was studied using real time RT-PCR based differential expression arrays, standard RT-PCR, and Western blot. Results High DcR3 in the peritoneal cavity of women with EOC is associated with significantly shorter time to first recurrence after platinum based therapy (p = 0.02). None-malignant cells contribute DcR3 in the peritoneal cavity. The cell lines studied do not secrete DcR3; however they all bind exogenous DcR3 to their surface implying that they can be effected by DcR3 from other sources. DcR3s protein binding partners are minimally expressed or negative, however, all cells expressed the DcR3 binding Heparan Sulfate Proteoglycans (HSPGs) Syndecans-2, and CD44v3. DcR3 binding was inhibited by heparin and heparinase. After DcR3 exposure both SKOV-3 and OVCAR-3 became more resistant to platinum with 15% more cells surviving at high doses. On the contrary CaOV3 became more sensitive to platinum with 20–25% more cell death. PCR array analysis showed increase expression of BRCA1 mRNA in SKOV-3 and OVCAR-3 and decreased BRCA1 expression in CaOV-3 after exposure to DcR3. This was confirmed by gene specific real time PCR and Western blot analysis. Conclusions Non-malignant cells contribute to the high levels of DcR3 in ovarian cancer. DcR3 binds readily to EOC cells via HSPGs and alter their responsiveness to platinum chemotherapy. The paradoxical responses seen were related to the expression pattern of HSPGs available on the cells surface to interact with. Although the mechanism behind this is not completely known alterations in DNA repair pathways including the expression of BRCA1 appear to be involved. PMID:22583667

  13. Two Faces of Chondroitin Sulfate Proteoglycan in Spinal Cord Repair: A Role in Microglia/Macrophage Activation

    PubMed Central

    London, Anat; Segev, Yifat; Jacob-Hirsch, Jasmin; Amariglio, Ninette; Rechavi, Gidon; Schwartz, Michal

    2008-01-01

    Background Chondroitin sulfate proteoglycan (CSPG) is a major component of the glial scar. It is considered to be a major obstacle for central nervous system (CNS) recovery after injury, especially in light of its well-known activity in limiting axonal growth. Therefore, its degradation has become a key therapeutic goal in the field of CNS regeneration. Yet, the abundant de novo synthesis of CSPG in response to CNS injury is puzzling. This apparent dichotomy led us to hypothesize that CSPG plays a beneficial role in the repair process, which might have been previously overlooked because of nonoptimal regulation of its levels. This hypothesis is tested in the present study. Methods and Findings We inflicted spinal cord injury in adult mice and examined the effects of CSPG on the recovery process. We used xyloside to inhibit CSPG formation at different time points after the injury and analyzed the phenotype acquired by the microglia/macrophages in the lesion site. To distinguish between the resident microglia and infiltrating monocytes, we used chimeric mice whose bone marrow-derived myeloid cells expressed GFP. We found that CSPG plays a key role during the acute recovery stage after spinal cord injury in mice. Inhibition of CSPG synthesis immediately after injury impaired functional motor recovery and increased tissue loss. Using the chimeric mice we found that the immediate inhibition of CSPG production caused a dramatic effect on the spatial organization of the infiltrating myeloid cells around the lesion site, decreased insulin-like growth factor 1 (IGF-1) production by microglia/macrophages, and increased tumor necrosis factor alpha (TNF-α) levels. In contrast, delayed inhibition, allowing CSPG synthesis during the first 2 d following injury, with subsequent inhibition, improved recovery. Using in vitro studies, we showed that CSPG directly activated microglia/macrophages via the CD44 receptor and modulated neurotrophic factor secretion by these cells. Conclusions Our results show that CSPG plays a pivotal role in the repair of injured spinal cord and in the recovery of motor function during the acute phase after the injury; CSPG spatially and temporally controls activity of infiltrating blood-borne monocytes and resident microglia. The distinction made in this study between the beneficial role of CSPG during the acute stage and its deleterious effect at later stages emphasizes the need to retain the endogenous potential of this molecule in repair by controlling its levels at different stages of post-injury repair. PMID:18715114

  14. Analysis of maternal-zygotic ugdh mutants reveals divergent roles for HSPGs in vertebrate embryogenesis and provides new insight into the initiation of left-right asymmetry.

    PubMed

    Superina, Simone; Borovina, Antonia; Ciruna, Brian

    2014-03-15

    Growth factors and morphogens regulate embryonic patterning, cell fate specification, cell migration, and morphogenesis. The activity and behavior of these signaling molecules are regulated in the extracellular space through interactions with proteoglycans (Bernfield et al., 1999; Perrimon and Bernfield 2000; Lander and Selleck 2000; Selleck 2000). Proteoglycans are high molecular-weight proteins consisting of a core protein with covalently linked glycosaminoglycan (GAG) side chains, which are thought to mediate ligand interaction. Drosophila mutant embryos deficient for UDP-glucose dehydrogenase activity (Ugdh, required for GAG synthesis) exhibit abnormal Fgf, Wnt and TGFß signaling and die during gastrulation, indicating a broad and critical role for proteoglycans during early embryonic development (Lin et al., 1999; Lin and Perrimon 2000) (Hacker et al., 1997). Mouse Ugdh mutants also die at gastrulation, however, only Fgf signaling appears disrupted (Garcia-Garcia and Anderson, 2003). These findings suggested a possible divergence in the requirement for proteoglycans during Drosophila and mouse embryogenesis, and that mammals may have evolved alternative means of regulating Wnt and TGFß activity. To further examine the function of proteoglycans in vertebrate development, we have characterized zebrafish mutants devoid of both maternal and zygotic Ugdh/Jekyll activity (MZjekyll). We demonstrate that MZjekyll mutant embryos display abnormal Fgf, Shh, and Wnt signaling activities, with concomitant defects in central nervous system patterning, cardiac ventricular fate specification and axial morphogenesis. Furthermore, we uncover a novel role for proteoglycans in left-right pattern formation. Our findings resolve longstanding questions into the evolutionary conservation of Ugdh function and provide new mechanistic insights into the initiation of left-right asymmetry. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Loss of intra-islet heparan sulfate is a highly sensitive marker of type 1 diabetes progression in humans.

    PubMed

    Simeonovic, Charmaine J; Popp, Sarah K; Starrs, Lora M; Brown, Debra J; Ziolkowski, Andrew F; Ludwig, Barbara; Bornstein, Stefan R; Wilson, J Dennis; Pugliese, Alberto; Kay, Thomas W H; Thomas, Helen E; Loudovaris, Thomas; Choong, Fui Jiun; Freeman, Craig; Parish, Christopher R

    2018-01-01

    Type 1 diabetes (T1D) is an autoimmune disease in which insulin-producing beta cells in pancreatic islets are progressively destroyed. Clinical trials of immunotherapies in recently diagnosed T1D patients have only transiently and partially impacted the disease course, suggesting that other approaches are required. Our previous studies have demonstrated that heparan sulfate (HS), a glycosaminoglycan conventionally expressed in extracellular matrix, is present at high levels inside normal mouse beta cells. Intracellular HS was shown to be critical for beta cell survival and protection from oxidative damage. T1D development in Non-Obese Diabetic (NOD) mice correlated with loss of islet HS and was prevented by inhibiting HS degradation by the endoglycosidase, heparanase. In this study we investigated the distribution of HS and heparan sulfate proteoglycan (HSPG) core proteins in normal human islets, a role for HS in human beta cell viability and the clinical relevance of intra-islet HS and HSPG levels, compared to insulin, in human T1D. In normal human islets, HS (identified by 10E4 mAb) co-localized with insulin but not glucagon and correlated with the HSPG core proteins for collagen type XVIII (Col18) and syndecan-1 (Sdc1). Insulin-positive islets of T1D pancreases showed significant loss of HS, Col18 and Sdc1 and heparanase was strongly expressed by islet-infiltrating leukocytes. Human beta cells cultured with HS mimetics showed significantly improved survival and protection against hydrogen peroxide-induced death, suggesting that loss of HS could contribute to beta cell death in T1D. We conclude that HS depletion in beta cells, possibly due to heparanase produced by insulitis leukocytes, may function as an important mechanism in the pathogenesis of human T1D. Our findings raise the possibility that intervention therapy with dual activity HS replacers/heparanase inhibitors could help to protect the residual beta cell mass in patients recently diagnosed with T1D.

  16. Musculocontractural Ehlers–Danlos syndrome and neurocristopathies: dermatan sulfate is required for Xenopus neural crest cells to migrate and adhere to fibronectin

    PubMed Central

    Gouignard, Nadège; Maccarana, Marco; Strate, Ina; von Stedingk, Kristoffer; Malmström, Anders

    2016-01-01

    ABSTRACT Of all live births with congenital anomalies, approximately one-third exhibit deformities of the head and face. Most craniofacial disorders are associated with defects in a migratory stem and progenitor cell population, which is designated the neural crest (NC). Musculocontractural Ehlers–Danlos syndrome (MCEDS) is a heritable connective tissue disorder with distinct craniofacial features; this syndrome comprises multiple congenital malformations that are caused by dysfunction of dermatan sulfate (DS) biosynthetic enzymes, including DS epimerase-1 (DS-epi1; also known as DSE). Studies in mice have extended our understanding of DS-epi1 in connective tissue maintenance; however, its role in fetal development is not understood. We demonstrate that DS-epi1 is important for the generation of isolated iduronic acid residues in chondroitin sulfate (CS)/DS proteoglycans in early Xenopus embryos. The knockdown of DS-epi1 does not affect the formation of early NC progenitors; however, it impairs the correct activation of transcription factors involved in the epithelial–mesenchymal transition (EMT) and reduces the extent of NC cell migration, which leads to a decrease in NC-derived craniofacial skeleton, melanocytes and dorsal fin structures. Transplantation experiments demonstrate a tissue-autonomous role for DS-epi1 in cranial NC cell migration in vivo. Cranial NC explant and single-cell cultures indicate a requirement of DS-epi1 in cell adhesion, spreading and extension of polarized cell processes on fibronectin. Thus, our work indicates a functional link between DS and NC cell migration. We conclude that NC defects in the EMT and cell migration might account for the craniofacial anomalies and other congenital malformations in MCEDS, which might facilitate the diagnosis and development of therapies for this distressing condition. Moreover, the presented correlations between human DS-epi1 expression and gene sets of mesenchymal character, invasion and metastasis in neuroblastoma and malignant melanoma suggest an association between DS and NC-derived cancers. PMID:27101845

  17. Tissue engineering approaches for studying the effect of biochemical and physiological stimuli on cell behavior

    NASA Astrophysics Data System (ADS)

    Jimenez Vergara, Andrea Carolina

    Tissue engineering (TE) approaches have emerged as an alternative to traditional tissue and organ replacements. The aim of this work was to contribute to the understanding of the effects of cell-material and endothelial cell (EC) paracrine signaling on cell responses using poly(ethylene glycol) diacrylate (PEGDA) hydrogels as a material platform. Three TE applications were explored. First, the effect of glycosaminoglycan (GAG) identity was evaluated for vocal fold restoration. Second, the influence of GAG identity was explored and a novel approach for stable endothelialization was developed for vascular graft applications. Finally, EC paracrine signaling in the presence of cyclic stretch, and hydrophobicity and inorganic content were studied for osteogenic applications. In terms of vocal fold restoration, it was found that vocal fold fibroblast (VFF) phenotype and extracellular matrix (ECM) production were impacted by GAG identity. VFF phenotype was preserved in long-term cultured hydrogels containing high molecular weight hyaluronan (HAHMW). Furthermore, collagen I deposition, fibronectin production and smooth muscle α-actin (SM-α-actin) expression in PEG-HA, PEG-chondroitin sulfate C and PEG-heparan sulfate (HS) gels suggest that CSC and HS may be undesirable for vocal fold implants. Regarding vascular graft applications, the impact of GAG identity on smooth muscle cell (SMC) foam cell formation was explored. Results support the increasing body of literature that suggests a critical role for dermatan sulfate (DS)-bearing proteoglycans in early atherosclerosis. In addition, an approach for fabricating bi-layered tissue engineering vascular grafts (TEVGs) with stable endothelialization was validated using PEGDA as an intercellular “cementing” agent between adjacent endothelial cells (ECs). Finally, mesenchymal stem cell (MSC) differentiation toward osteogenic like cells was evaluated. ECM and cell phenotypic data showed that elevated scaffold inorganic content and hydrophobicity were indeed correlated with increased osteogenic differentiation. Moreover, the present results suggest that EC paracrine signaling enhances MSC osteogenesis in the presence of cyclic stretch.

  18. Musculocontractural Ehlers-Danlos syndrome and neurocristopathies: dermatan sulfate is required for Xenopus neural crest cells to migrate and adhere to fibronectin.

    PubMed

    Gouignard, Nadège; Maccarana, Marco; Strate, Ina; von Stedingk, Kristoffer; Malmström, Anders; Pera, Edgar M

    2016-06-01

    Of all live births with congenital anomalies, approximately one-third exhibit deformities of the head and face. Most craniofacial disorders are associated with defects in a migratory stem and progenitor cell population, which is designated the neural crest (NC). Musculocontractural Ehlers-Danlos syndrome (MCEDS) is a heritable connective tissue disorder with distinct craniofacial features; this syndrome comprises multiple congenital malformations that are caused by dysfunction of dermatan sulfate (DS) biosynthetic enzymes, including DS epimerase-1 (DS-epi1; also known as DSE). Studies in mice have extended our understanding of DS-epi1 in connective tissue maintenance; however, its role in fetal development is not understood. We demonstrate that DS-epi1 is important for the generation of isolated iduronic acid residues in chondroitin sulfate (CS)/DS proteoglycans in early Xenopus embryos. The knockdown of DS-epi1 does not affect the formation of early NC progenitors; however, it impairs the correct activation of transcription factors involved in the epithelial-mesenchymal transition (EMT) and reduces the extent of NC cell migration, which leads to a decrease in NC-derived craniofacial skeleton, melanocytes and dorsal fin structures. Transplantation experiments demonstrate a tissue-autonomous role for DS-epi1 in cranial NC cell migration in vivo Cranial NC explant and single-cell cultures indicate a requirement of DS-epi1 in cell adhesion, spreading and extension of polarized cell processes on fibronectin. Thus, our work indicates a functional link between DS and NC cell migration. We conclude that NC defects in the EMT and cell migration might account for the craniofacial anomalies and other congenital malformations in MCEDS, which might facilitate the diagnosis and development of therapies for this distressing condition. Moreover, the presented correlations between human DS-epi1 expression and gene sets of mesenchymal character, invasion and metastasis in neuroblastoma and malignant melanoma suggest an association between DS and NC-derived cancers. © 2016. Published by The Company of Biologists Ltd.

  19. Synovial joint formation requires local Ext1 expression and heparan sulfate production in developing mouse embryo limbs and spine.

    PubMed

    Mundy, Christina; Yasuda, Tadashi; Kinumatsu, Takashi; Yamaguchi, Yu; Iwamoto, Masahiro; Enomoto-Iwamoto, Motomi; Koyama, Eiki; Pacifici, Maurizio

    2011-03-01

    Heparan sulfate proteoglycans (HSPGs) regulate a number of major developmental processes, but their roles in synovial joint formation remain unknown. Here we created conditional mouse embryo mutants lacking Ext1 in developing joints by mating Ext1(f/f) and Gdf5-Cre mice. Ext1 encodes a subunit of the Ext1/Ext2 Golgi-associated protein complex responsible for heparan sulfate (HS) synthesis. The proximal limb joints did form in the Gdf5-Cre;Ext1(f/f) mutants, but contained an uneven articulating superficial zone that expressed very low lubricin levels. The underlying cartilaginous epiphysis was deranged as well and displayed random patterns of cell proliferation and matrillin-1 and collagen IIA expression, indicative of an aberrant phenotypic definition of the epiphysis itself. Digit joints were even more affected, lacked a distinct mesenchymal interzone and were often fused likely as a result of local abnormal BMP and hedgehog activity and signaling. Interestingly, overall growth and lengthening of long bones were also delayed in the mutants. To test whether Ext1 function is needed for joint formation at other sites, we examined the spine. Indeed, entire intervertebral discs, normally composed by nucleus pulposus surrounded by the annulus fibrosus, were often missing in Gdf5-Cre;Ext1(f/f) mice. When disc remnants were present, they displayed aberrant organization and defective joint marker expression. Similar intervertebral joint defects and fusions occurred in Col2-Cre;β-catenin(f/f) mutants. The study provides novel evidence that local Ext1 expression and HS production are needed to maintain the phenotype and function of joint-forming cells and coordinate local signaling by BMP, hedgehog and Wnt/β-catenin pathways. The data indicate also that defects in joint formation reverberate on, and delay, overall long bone growth. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. Massive aggrecan and versican accumulation in thoracic aortic aneurysm and dissection

    PubMed Central

    Cikach, Frank S.; Koch, Christopher D.; Mead, Timothy J.; Galatioto, Josephine; Willard, Belinda B.; Emerton, Kelly B.; Eagleton, Matthew J.; Blackstone, Eugene H.; Ramirez, Francesco; Roselli, Eric E.; Apte, Suneel S.

    2018-01-01

    Proteoglycan accumulation is a hallmark of medial degeneration in thoracic aortic aneurysm and dissection (TAAD). Here, we defined the aortic proteoglycanome using mass spectrometry, and based on the findings, investigated the large aggregating proteoglycans aggrecan and versican in human ascending TAAD and a mouse model of severe Marfan syndrome. The aortic proteoglycanome comprises 20 proteoglycans including aggrecan and versican. Antibodies against these proteoglycans intensely stained medial degeneration lesions in TAAD, contrasting with modest intralamellar staining in controls. Aggrecan, but not versican, was increased in longitudinal analysis of Fbn1mgR/mgR aortas. TAAD and Fbn1mgR/mgR aortas had increased aggrecan and versican mRNAs, and reduced expression of a key proteoglycanase gene, ADAMTS5, was seen in TAAD. Fbn1mgR/mgR mice with ascending aortic dissection and/or rupture had dramatically increased aggrecan staining compared with mice without these complications. Thus, aggrecan and versican accumulation in ascending TAAD occurs via increased synthesis and/or reduced proteolytic turnover, and correlates with aortic dissection/rupture in Fbn1mgR/mgR mice. Tissue swelling imposed by aggrecan and versican is proposed to be profoundly deleterious to aortic wall mechanics and smooth muscle cell homeostasis, predisposing to type-A dissections. These proteoglycans provide potential biomarkers for refined risk stratification and timing of elective aortic aneurysm repair. PMID:29515038

  1. Massive aggrecan and versican accumulation in thoracic aortic aneurysm and dissection.

    PubMed

    Cikach, Frank S; Koch, Christopher D; Mead, Timothy J; Galatioto, Josephine; Willard, Belinda B; Emerton, Kelly B; Eagleton, Matthew J; Blackstone, Eugene H; Ramirez, Francesco; Roselli, Eric E; Apte, Suneel S

    2018-03-08

    Proteoglycan accumulation is a hallmark of medial degeneration in thoracic aortic aneurysm and dissection (TAAD). Here, we defined the aortic proteoglycanome using mass spectrometry, and based on the findings, investigated the large aggregating proteoglycans aggrecan and versican in human ascending TAAD and a mouse model of severe Marfan syndrome. The aortic proteoglycanome comprises 20 proteoglycans including aggrecan and versican. Antibodies against these proteoglycans intensely stained medial degeneration lesions in TAAD, contrasting with modest intralamellar staining in controls. Aggrecan, but not versican, was increased in longitudinal analysis of Fbn1mgR/mgR aortas. TAAD and Fbn1mgR/mgR aortas had increased aggrecan and versican mRNAs, and reduced expression of a key proteoglycanase gene, ADAMTS5, was seen in TAAD. Fbn1mgR/mgR mice with ascending aortic dissection and/or rupture had dramatically increased aggrecan staining compared with mice without these complications. Thus, aggrecan and versican accumulation in ascending TAAD occurs via increased synthesis and/or reduced proteolytic turnover, and correlates with aortic dissection/rupture in Fbn1mgR/mgR mice. Tissue swelling imposed by aggrecan and versican is proposed to be profoundly deleterious to aortic wall mechanics and smooth muscle cell homeostasis, predisposing to type-A dissections. These proteoglycans provide potential biomarkers for refined risk stratification and timing of elective aortic aneurysm repair.

  2. Biomimetic soluble collagen purified from bones.

    PubMed

    Ferreira, Ana Marina; Gentile, Piergiorgio; Sartori, Susanna; Pagliano, Cristina; Cabrele, Chiara; Chiono, Valeria; Ciardelli, Gianluca

    2012-11-01

    Type I collagen has been extensively exploited as a biomaterial for biomedical applications and drug delivery; however, small molecular alterations occurring during the isolation procedure and its interaction with residual bone extracellular matrix molecules or proteins might affect the overall material biocompatibility and performance. The aim of the current work is to study the potential alterations in collagen properties and organization associated with the absence of proteoglycans, which mimic pathological conditions associated with age-related diseases. A new approach for evaluating the effect of proteoglycans on the properties of isolated type I collagen from the bone matrix is described. Additional treatment with guanidine hydrochloride was introduced to remove residual proteoglycans from the collagen matrix. The properties of the isolated collagen with/without guanidine hydrochloride treatment were investigated and compared with a commercial rabbit collagen as control. We demonstrate that the absence of proteoglycans in the isolated type I collagen affects its thermal properties, the extraction into its native structure, and its ability to hydrate and self-assemble into fibers. The fine control and tuning of all these features, linked to the absence of non-collagenous proteins as proteoglycans, offer the possibility of designing new strategies and biomaterials with advanced biomimetic properties aimed at regenerating bone tissue in the case of fragility and/or defects. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Microgravity in the STS-29 space shuttle discovery affected the vestibular system of chick embryos

    NASA Technical Reports Server (NTRS)

    Fermin, C. D.; Martin, D.; Jones, T.; Vellinger, J.; Deuser, M.; Hester, P.; Hullinger, R.

    1996-01-01

    Out of 32 embryos flown (16 @ E2 + 16 @ E9) for 5 days, 16 survived. All sixteen E2 were dead at landing. Eight were opened and eight were incubated at 1.0G. Autopsy showed that 4 E2 survived over 24 hours in space. Eight E14 hatched without anatomical malformations, and 8 E14 were fixed. The height of the macular epithelia was 31 mu m (mean) in control and 26 mu m in flight chicks. The cross-sectional area of macular nuclei of control was 17 mu m(2) for hair cells and 14 mu m(2) in supporting cells. In flight, cross-sectional area was 17 mu m(2) in hair cells and 15 mu m(2) in supporting cells (n=250). The shape factor of cartilage cells (1.0 = perfect circle) between control (mean = 0.70) and flight (mean = 0.72), and the area of cartilaginous cells between controls (mean = 9 mu m(2)) and flight (mean = 9 mu m(2)) did not differ (n=300). The nuclei of support cells were closer to the basement membrane in flight than in control chicks. The immunoreactivity of otoconia with anti keratan, fibronectin or chrondroitin sulfate was not different between flight and control ears. There were more afferent fibers inside the macular epithelia of flight (p<0.05) than control. Three of 8 flight animals had elevated vestibular thresholds (VT), with normal mean response amplitudes and latencies. Modified afferent innervation patterns requiring weeks to compensate are sufficient to elevate VT, and should be investigated further. Other reversible (sublethal) microgravity effects on sensory epithelia (vacuoles, swelling, etc) require quantification.

  4. Novel mutations in the CHST6 gene associated with macular corneal dystrophy in southern India.

    PubMed

    Warren, John F; Aldave, Anthony J; Srinivasan, M; Thonar, Eugene J; Kumar, Abha B; Cevallos, Vicky; Whitcher, John P; Margolis, Todd P

    2003-11-01

    To further characterize the role of the carbohydrate sulfotransferase (CHST6) gene in macular corneal dystrophy (MCD) through identification of causative mutations in a cohort of affected patients from southern India. Genomic DNA was extracted from buccal epithelium of 75 patients (51 families) with MCD, 33 unaffected relatives, and 48 healthy volunteers. The coding region of the CHST6 gene was evaluated by means of polymerase chain reaction amplification and direct sequencing. Subtyping of MCD into types I and II was performed by measuring serum levels of antigenic keratan sulfate. Seventy patients were classified as having type I MCD, and 5 patients as having type II MCD. Analysis of the CHST6 coding region in patients with type I MCD identified 11 homozygous missense mutations (Leu22Arg, His42Tyr, Arg50Cys, Arg50Leu, Ser53Leu, Arg97Pro, Cys102Tyr, Arg127Cys, Arg205Gln, His249Pro, and Glu274Lys), 2 compound heterozygous missense mutations (Arg93His and Ala206Thr), 5 homozygous deletion mutations (delCG707-708, delC890, delA1237, del1748-1770, and delORF), and 2 homozygous replacement mutations (ACCTAC 1273 GGT, and GCG 1304 AT). One patient with type II MCD was heterozygous for the C890 deletion mutation, whereas 4 possessed no CHST6 coding region mutations. A variety of previously unreported mutations in the coding region of the CHST6 gene are associated with type I MCD in a cohort of patients in southern India. An improved understanding of the genetic basis of MCD allows for earlier, more accurate diagnosis of affected individuals, and may provide the foundation for the development of novel disease treatments.

  5. Macular corneal dystrophy in a Chinese family related with novel mutations of CHST6

    PubMed Central

    Dang, Xiuhong; Zhu, Qingguo; Wang, Li; Su, Hong; Lin, Hui; Zhou, Nan; Liang, Ting; Wang, Zheng; Huang, Shangzhi; Ren, Qiushi

    2009-01-01

    Purpose To identify mutations in the carbohydrate sulfotransferase gene (CHST6) for a Chinese family with macular corneal dystrophy (MCD) and to investigate the histopathological changes in the affected cornea. Methods A corneal button of the proband was obtained by penetrating keratoplasty. The half button and ultrathin sections from the other half button were examined with special stains under a light microscope (LM) and an electron microscope (EM) separately. Genomic DNA was extracted from peripheral blood of 11 family members, and the coding region of CHST6 was amplified by the polymerase chain reaction (PCR) method. The PCR products were analyzed by direct sequencing and restriction enzyme digestion. Results The positive reaction to colloidal iron stain (extracellular blue accumulations in the stroma) was detected under light microscopy. Transmission electron microscopy revealed the enlargement of smooth endoplasmic reticulum and the presence of intracytoplasmic vacuoles. The compound heterozygous mutations, c.892C>T and c.1072T>C, were identified in exon 3 of CHST6 in three patients. The two transversions resulted in the substitution of a stop codon for glutamine at codon 298 (p.Q298X) and a missense mutation at codon 358, tyrosine to histidine (p.Y358H). The six unaffected family individuals carried alternative heterozygous mutations. These two mutations were not detected in any of the 100 control subjects. Conclusions Those novel compound heterozygous mutations were thought to contribute to the loss of CHST6 function, which induced the abnormal metabolism of keratan sulfate (KS) that deposited in the corneal stroma. It could be proved by the observation of a positive stain reaction and the enlarged collagen fibers as well as hyperplastic fibroblasts under microscopes. PMID:19365571

  6. 3D Functional Corneal Stromal Tissue Equivalent Based on Corneal Stromal Stem Cells and Multi-Layered Silk Film Architecture.

    PubMed

    Ghezzi, Chiara E; Marelli, Benedetto; Omenetto, Fiorenzo G; Funderburgh, James L; Kaplan, David L

    2017-01-01

    The worldwide need for human cornea equivalents continues to grow. Few clinical options are limited to allogenic and synthetic material replacements. We hypothesized that tissue engineered human cornea systems based on mechanically robust, patterned, porous, thin, optically clear silk protein films, in combination with human corneal stromal stem cells (hCSSCs), would generate 3D functional corneal stroma tissue equivalents, in comparison to previously developed 2D approaches. Silk film contact guidance was used to control the alignment and distribution of hCSSCs on RGD-treated single porous silk films, which were then stacked in an orthogonally, multi-layered architecture and cultured for 9 weeks. These systems were compared similar systems generated with human corneal fibroblasts (hCFs). Both cell types were viable and preferentially aligned along the biomaterial patterns for up to 9 weeks in culture. H&E histological sections showed that the systems seeded with the hCSSCs displayed ECM production throughout the entire thickness of the constructs. In addition, the ECM proteins tested positive for keratocyte-specific tissue markers, including keratan sulfate, lumican, and keratocan. The quantification of hCSSC gene expression of keratocyte-tissue markers, including keratocan, lumican, human aldehyde dehydrogenase 3A1 (ALDH3A1), prostaglandin D2 synthase (PTDGS), and pyruvate dehydrogenase kinase, isozyme 4 (PDK4), within the 3D tissue systems demonstrated upregulation when compared to 2D single silk films and to the systems generated with the hCFs. Furthermore, the production of ECM from the hCSSC seeded systems and subsequent remodeling of the initial matrix significantly improved cohesiveness and mechanical performance of the constructs, while maintaining transparency after 9 weeks.

  7. Peptide p5 binds both heparinase-sensitive glycosaminoglycans and fibrils in patient-derived AL amyloid extracts.

    PubMed

    Martin, Emily B; Williams, Angela; Heidel, Eric; Macy, Sallie; Kennel, Stephen J; Wall, Jonathan S

    2013-06-21

    In previously published work, we have described heparin-binding synthetic peptides that preferentially recognize amyloid deposits in a mouse model of reactive systemic (AA) amyloidosis and can be imaged by using positron and single photon emission tomographic imaging. We wanted to extend these findings to the most common form of visceral amyloidosis, namely light chain (AL); however, there are no robust experimental animal models of AL amyloidosis. To further define the binding of the lead peptide, p5, to AL amyloid, we characterized the reactivity in vitro of p5 with in situ and patient-derived AL amyloid extracts which contain both hypersulfated heparan sulfate proteoglycans as well as amyloid fibrils. Histochemical staining demonstrated that the peptide specifically localized with tissue-associated AL amyloid deposits. Although we anticipated that p5 would undergo electrostatic interactions with the amyloid-associated glycosaminoglycans expressing heparin-like side chains, no significant correlation between peptide binding and glycosaminoglycan content within amyloid extracts was observed. In contrast, following heparinase I treatment, although overall binding was reduced, a positive correlation between peptide binding and amyloid fibril content became evident. This interaction was further confirmed using synthetic light chain fibrils that contain no carbohydrates. These data suggest that p5 can bind to both the sulfated glycosaminoglycans and protein fibril components of AL amyloid. Understanding these complex electrostatic interactions will aid in the optimization of synthetic peptides for use as amyloid imaging agents and potentially as therapeutics for the treatment of amyloid diseases. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. The effects of high-dose methotrexate on the development of cartilage lesions in a lapine model of osteoarthrosis.

    PubMed

    Neidel, J; Schroers, B; Sintermann, F

    1998-01-01

    To determine whether systemic administration of methotrexate (MTX) can prevent joint destruction in experimental osteoarthrosis (OA) in rabbits, the disorder was induced unilaterally in the knee joints of 40 rabbits by partial medial meniscectomy and sectioning of the medial collateral and both cruciate ligaments. A sham operation (arthrotomy only) was performed in another four animals. Effects on the cartilage of the femoral condyles were studied after 6 and 12 weeks. Twelve weeks after induction, femoral and tibial osteophyte formation was demonstrated on radiographs in all cases. Marked cartilage damage was found histologically (median Mankin score 10 vs 1 for non-operated controls; P < 0.05, Wilcoxon test). Cartilage proteoglycan (GAG) content (dye binding assay) was reduced in operated joints [63 +/- 8 (mean +/- SEM) vs 75 +/- 6 micrograms chondroitin sulfate/mg cartilage wet weight], and the leukocyte count in the joints was elevated (226 +/- 14 vs 7 +/- 3 leukocytes per microliter joint aspirate after injection of 0.5 ml saline solution; both P < 0.05, Wilcoxon test). The rate of GAG synthesis was unchanged (ex vivo labelling with 35S-sulfate). Treatment with MTX (30 mg x kg body weight-1 x week-1 i.m., starting 12 h postoperatively) reduced cartilage damage (median Mankin score 8 vs 10 for placebo, P < 0.05, Mann-Whitney U-test), but had no significant effect on the other parameters tested. No significant MTX effects were observed on cartilage from nonoperated joints. Our data indicate that MTX may have a limited therapeutic effect in experimental OA in the rabbit.

  9. An Automated, High-Throughput Method for Interpreting the Tandem Mass Spectra of Glycosaminoglycans

    NASA Astrophysics Data System (ADS)

    Duan, Jiana; Jonathan Amster, I.

    2018-05-01

    The biological interactions between glycosaminoglycans (GAGs) and other biomolecules are heavily influenced by structural features of the glycan. The structure of GAGs can be assigned using tandem mass spectrometry (MS2), but analysis of these data, to date, requires manually interpretation, a slow process that presents a bottleneck to the broader deployment of this approach to solving biologically relevant problems. Automated interpretation remains a challenge, as GAG biosynthesis is not template-driven, and therefore, one cannot predict structures from genomic data, as is done with proteins. The lack of a structure database, a consequence of the non-template biosynthesis, requires a de novo approach to interpretation of the mass spectral data. We propose a model for rapid, high-throughput GAG analysis by using an approach in which candidate structures are scored for the likelihood that they would produce the features observed in the mass spectrum. To make this approach tractable, a genetic algorithm is used to greatly reduce the search-space of isomeric structures that are considered. The time required for analysis is significantly reduced compared to an approach in which every possible isomer is considered and scored. The model is coded in a software package using the MATLAB environment. This approach was tested on tandem mass spectrometry data for long-chain, moderately sulfated chondroitin sulfate oligomers that were derived from the proteoglycan bikunin. The bikunin data was previously interpreted manually. Our approach examines glycosidic fragments to localize SO3 modifications to specific residues and yields the same structures reported in literature, only much more quickly.

  10. Facilitation of learning and modulation of frontal cortex acetylcholine by ventral pallidal injection of heparin glucosaminoglycan.

    PubMed

    De Souza Silva, M A; Jezek, K; Weth, K; Müller, H W; Huston, J P; Brandao, M L; Hasenöhrl, R U

    2002-01-01

    We examined the effects of heparin on learning and frontal cortex acetylcholine parameters following injection of the glucosaminoglycan into the ventral pallidum. In Experiment 1, possible mnemoactive effects of intrapallidal heparin injection were assessed. Rats with chronically implanted cannulae were administered heparin (0.1, 1.0, 10 ng) or vehicle (0.5 microl) and were tested on a one-trial step-through avoidance task. Two retention tests were carried out in each animal, one at 1.5 h after training to measure short-term memory and another at 24 h to measure long-term memory. Post-trial intrapallidal injection of 1.0 ng heparin improved both short- and long-term retention of the task, whereas the lower and the higher dose of the glucosaminoglycan had no effect. When the effective dose of heparin was injected 5 h, rather than immediately after training, it no longer facilitated long-term retention of the conditioned avoidance response. In Experiment 2, the effects of ventral pallidal heparin injection on frontal cortex acetylcholine and choline concentrations were investigated with in vivo microdialysis in anaesthetized rats. Heparin, administered in the dose of 1.0 ng, which was effective in facilitating avoidance performance, produced a delayed increase in cortical acetylcholine levels ipsi- and contralaterally to the side of intrabasalis injection, resembling the known neurochemical effects obtained for another glycosaminoglycan, chondroitin sulfate, which recently was shown to facilitate inhibitory avoidance learning and to increase frontal cortex acetylcholine. The present findings indicate that heparin, like other extracellular matrix proteoglycans, can exert beneficial effects on memory and strengthen the presumptive relationship between such promnestic effects of proteoglycans and basal forebrain cholinergic mechanisms. The data are discussed with respect to the presumed roles of matrix molecules in extrasynaptic volume transmission and in the 'cross-talk' between synapses.

  11. The Development and Activity-Dependent Expression of Aggrecan in the Cat Visual Cortex

    PubMed Central

    Sengpiel, F.; Beaver, C. J.; Crocker-Buque, A.; Kelly, G. M.; Matthews, R. T.; Mitchell, D. E.

    2013-01-01

    The Cat-301 monoclonal antibody identifies aggrecan, a chondroitin sulfate proteoglycan in the cat visual cortex and dorsal lateral geniculate nucleus (dLGN). During development, aggrecan expression increases in the dLGN with a time course that matches the decline in plasticity. Moreover, examination of tissue from selectively visually deprived cats shows that expression is activity dependent, suggesting a role for aggrecan in the termination of the sensitive period. Here, we demonstrate for the first time that the onset of aggrecan expression in area 17 also correlates with the decline in experience-dependent plasticity in visual cortex and that this expression is experience dependent. Dark rearing until 15 weeks of age dramatically reduced the density of aggrecan-positive neurons in the extragranular layers, but not in layer IV. This effect was reversible as dark-reared animals that were subsequently exposed to light showed normal numbers of Cat-301-positive cells. The reduction in aggrecan following certain early deprivation regimens is the first biochemical correlate of the functional changes to the γ-aminobutyric acidergic system that have been reported following early deprivation in cats. PMID:22368089

  12. HIV internalization into oral and genital epithelial cells by endocytosis and macropinocytosis leads to viral sequestration in the vesicles

    PubMed Central

    Yasen, Aizezi; Herrera, Rossana; Rosbe, Kristina; Lien, Kathy; Tugizov, Sharof M.

    2018-01-01

    Recently, we showed that HIV-1 is sequestered, i.e., trapped, in the intracellular vesicles of oral and genital epithelial cells. Here, we investigated the mechanisms of HIV-1 sequestration in vesicles of polarized tonsil, foreskin and cervical epithelial cells. HIV-1 internalization into epithelial cells is initiated by multiple entry pathways, including clathrin-, caveolin/lipid raft-associated endocytosis and macropinocytosis. Inhibition of HIV-1 attachment to galactosylceramide and heparan sulfate proteoglycans, and virus endocytosis and macropinocytosis reduced HIV-1 sequestration by 30–40%. T-cell immunoglobulin and mucin domain 1 (TIM-1) were expressed on the apical surface of polarized tonsil, cervical and foreskin epithelial cells. However, TIM-1-associated HIV-1 macropinocytosis and sequestration were detected mostly in tonsil epithelial cells. Sequestered HIV-1 was resistant to trypsin, pronase, and soluble CD4, indicating that the sequestered virus was intracellular. Inhibition of HIV-1 intraepithelial sequestration and elimination of vesicles containing virus in the mucosal epithelium may help in the prevention of HIV-1 mucosal transmission. PMID:29277006

  13. Knockdown of versican 1 blocks cigarette-induced loss of insoluble elastin in human lung fibroblasts.

    PubMed

    Xu, Lu-lu; Lu, Yun-tao; Zhang, Jing; Wu, Lian; Merrilees, Mervyn J; Qu, Jie-ming

    2015-08-15

    COPD lung is characterized by loss of alveolar elastic fibers and an increase in the chondroitin sulfate (CS) matrix proteoglycan versican V1 (V1). V1 is a known inhibitor of elastic fiber deposition and this study investigates the effects of knockdown of V1, and add-back of CS, on CCL-210 lung fibroblasts treated with cigarette smoke extract (CSE) as a model for COPD. CSE inhibited fibroblast proliferation, viability, tropoelastin synthesis, and elastin deposition, and increased V1 synthesis and secretion. V1 siRNA decreased V1 and constituent CS, did not affect tropoelastin production, but blocked the CSE-induced loss in insoluble elastin. Exogenous CS reduced insoluble elastin, even in the presence of V1 siRNA. These findings confirm that V1 and CS impair the assembly of tropoelastin monomers into insoluble fibers, and further demonstrate that specific knockdown of V1 alleviates the impaired assembly of elastin seen in cultures of pulmonary fibroblasts exposed to CSE, indicating a regulatory role for this protein in the pathophysiology of COPD. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. A heparin-functionalized carbon nanotube-based affinity biosensor for dengue virus.

    PubMed

    Wasik, Daniel; Mulchandani, Ashok; Yates, Marylynn V

    2017-05-15

    Dengue virus is an arthropod-borne virus transmitted primarily by Aedes mosquitos and is major cause of disease in tropical and subtropical regions. Colloquially known as Dengue Fever, infection can cause hemorrhagic disorders and death in humans and non-human primates. We report a novel electronic biosensor based on a single-walled carbon nanotube network chemiresistive transducer that is functionalized with heparin for low-cost, label-free, ultra-sensitive, and rapid detection of whole dengue virus (DENV). Heparin, an analog of the heparan sulfate proteoglycans that are receptors for dengue virus during infection of Vero cells and hepatocytes, was used for the first time in a biosensor as a biorecognition element instead of traditional antibody. Detection of DENV in viral culture supernatant has similar sensitivity as the corresponding viral titer in phosphate buffer despite the presence of growth media and Vero cell lysate. The biosensor demonstrated sensitivity within the clinically relevant range for humans and infected Aedes aegypti. It has potential application in clinical diagnosis and can improve point-of-care diagnostics of dengue infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Alport syndrome and Pierson syndrome: Diseases of the glomerular basement membrane.

    PubMed

    Funk, Steven D; Lin, Meei-Hua; Miner, Jeffrey H

    2018-04-16

    The glomerular basement membrane (GBM) is an important component of the kidney's glomerular filtration barrier. Like all basement membranes, the GBM contains type IV collagen, laminin, nidogen, and heparan sulfate proteoglycan. It is flanked by the podocytes and glomerular endothelial cells that both synthesize it and adhere to it. Mutations that affect the GBM's collagen α3α4α5(IV) components cause Alport syndrome (kidney disease with variable ear and eye defects) and its variants, including thin basement membrane nephropathy. Mutations in LAMB2 that impact the synthesis or function of laminin α5β2γ1 (LM-521) cause Pierson syndrome (congenital nephrotic syndrome with eye and neurological defects) and its less severe variants, including isolated congenital nephrotic syndrome. The very different types of kidney diseases that result from mutations in collagen IV vs. laminin are likely due to very different pathogenic mechanisms. A better understanding of these mechanisms should lead to targeted therapeutic approaches that can help people with these rare but important diseases. Copyright © 2017 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.

  16. p27 Nuclear localization and growth arrest caused by perlecan knockdown in human endothelial cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sakai, Katsuya; Oka, Kiyomasa; Matsumoto, Kunio

    2010-02-12

    Perlecan, a secreted heparan sulfate proteoglycan, is a major component of the vascular basement membrane and participates in angiogenesis. Here, we used small interference RNA-mediated knockdown of perlecan expression to investigate the regulatory function of perlecan in the growth of human vascular endothelial cells. Basic fibroblast growth factor (bFGF)-induced ERK phosphorylation and cyclin D1 expression were unchanged by perlecan deficiency in endothelial cells; however, perlecan deficiency inhibited the Rb protein phosphorylation and DNA synthesis induced by bFGF. By contrast to cytoplasmic localization of the cyclin-dependent kinase inhibitor p27 in control endothelial cells, p27 was localized in the nucleus and itsmore » expression increased in perlecan-deficient cells, which suggests that p27 mediates inhibition of Rb phosphorylation. In addition to the well-characterized function of perlecan as a co-receptor for heparin-binding growth factors such as bFGF, our results suggest that perlecan plays an indispensible role in endothelial cell proliferation and acts through a mechanism that involves subcellular localization of p27.« less

  17. Peripheral Nervous System Genes Expressed in Central Neurons Induce Growth on Inhibitory Substrates

    PubMed Central

    Buchser, William J.; Smith, Robin P.; Pardinas, Jose R.; Haddox, Candace L.; Hutson, Thomas; Moon, Lawrence; Hoffman, Stanley R.; Bixby, John L.; Lemmon, Vance P.

    2012-01-01

    Trauma to the spinal cord and brain can result in irreparable loss of function. This failure of recovery is in part due to inhibition of axon regeneration by myelin and chondroitin sulfate proteoglycans (CSPGs). Peripheral nervous system (PNS) neurons exhibit increased regenerative ability compared to central nervous system neurons, even in the presence of inhibitory environments. Previously, we identified over a thousand genes differentially expressed in PNS neurons relative to CNS neurons. These genes represent intrinsic differences that may account for the PNS’s enhanced regenerative ability. Cerebellar neurons were transfected with cDNAs for each of these PNS genes to assess their ability to enhance neurite growth on inhibitory (CSPG) or permissive (laminin) substrates. Using high content analysis, we evaluated the phenotypic profile of each neuron to extract meaningful data for over 1100 genes. Several known growth associated proteins potentiated neurite growth on laminin. Most interestingly, novel genes were identified that promoted neurite growth on CSPGs (GPX3, EIF2B5, RBMX). Bioinformatic approaches also uncovered a number of novel gene families that altered neurite growth of CNS neurons. PMID:22701605

  18. Endorepellin causes endothelial cell disassembly of actin cytoskeleton and focal adhesions through α2β1 integrin

    PubMed Central

    Bix, Gregory; Fu, Jian; Gonzalez, Eva M.; Macro, Laura; Barker, Amy; Campbell, Shelly; Zutter, Mary M.; Santoro, Samuel A.; Kim, Jiyeun K.; Höök, Magnus; Reed, Charles C.; Iozzo, Renato V.

    2004-01-01

    Endorepellin, the COOH-terminal domain of the heparan sulfate proteoglycan perlecan, inhibits several aspects of angiogenesis. We provide evidence for a novel biological axis that links a soluble fragment of perlecan protein core to the major cell surface receptor for collagen I, α2β1 integrin, and provide an initial investigation of the intracellular signaling events that lead to endorepellin antiangiogenic activity. The interaction between endorepellin and α2β1 integrin triggers a unique signaling pathway that causes an increase in the second messenger cAMP; activation of two proximal kinases, protein kinase A and focal adhesion kinase; transient activation of p38 mitogen-activated protein kinase and heat shock protein 27, followed by a rapid down-regulation of the latter two proteins; and ultimately disassembly of actin stress fibers and focal adhesions. The end result is a profound block of endothelial cell migration and angiogenesis. Because perlecan is present in both endothelial and smooth muscle cell basement membranes, proteolytic activity during the initial stages of angiogenesis could liberate antiangiogenic fragments from blood vessels' walls, including endorepellin. PMID:15240572

  19. Interaction of PF4 (CXCL4) with the vasculature: a role in atherosclerosis and angiogenesis.

    PubMed

    Aidoudi, Sallouha; Bikfalvi, Andreas

    2010-11-01

    Platelet factor-4 (PF4), a platelet-derived chemokine, has two important functions in the vasculature. It has a pro-atherogenic role while also having anti-angiogenic effects. The activity of platelet factor-4 (PF4), unlike other chemokines that bind to specific receptors, depends on its unusually high affinity for proteoglycans and other negatively charged molecules. High affinity for heparan sulfates was thought to be central to all of PF4's biological functions. However, other mechanisms have been described such as direct growth factor binding, activation of the CXCR3B chemokine receptor isoform that is present in some vascular cells or binding to lipoprotein-related protein-1 (LRP1). Furthermore, PF4 also binds to integrins with affinities similar to matrix molecules. These interactions may explain the effects of PF4 in healthy and pathological tissues. However, the mechanisms involved in PF4's activity are complex and may depend on a given tissue or localisation. Overall, while much is already known about PF4, its specific role in atherosclerosis and angiogenesis remains still to be clarified.

  20. Structural differences between cell matrix and culture medium N-linked oligosaccharides on heavy proteochondroitin sulfate proteoglycan (PCS-H)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cioffi, L.; Conrad, H.E.

    1986-05-01

    Tibial chondrocytes were labeled metabolically with /sup 3/H-man and the PCS-H was isolated from the culture medium (CM) and the cell matrix (Ma) pools. Equal amounts of /sup 3/H were incorporated into the PCS-H of the CM and Ma pools. The PCS-H pools were digested with thermolysin, Chondroitinase, and then N-glycanase, and the N-linked oligosaccharides were chromatographed on Con-A Sepharose. The ratios of complex to high mannose oligosaccharides for the CM and Ma were 6.1 and 2.6, respectively. More than 60% of the complex CM N-linked oligosaccharides were charged species whereas only 40% of the Ma N-linked oligosaccharides were charged.more » The oligosaccharides were analyzed by HPLC. Both complex and high mannose oligosaccharides found in the PCS-H of the CM and Ma pools were mixtures of identical structures but the amounts of each structure in the two pools showed marked differences. These observations indicate that distinct PCS-H species are found in the CM and Ma pools.« less

  1. Merging colloidal nanoplasmonics and surface plasmon resonance spectroscopy for enhanced profiling of multiple myeloma-derived exosomes.

    PubMed

    Di Noto, Giuseppe; Bugatti, Antonella; Zendrini, Andrea; Mazzoldi, Elena Laura; Montanelli, Alessandro; Caimi, Luigi; Rusnati, Marco; Ricotta, Doris; Bergese, Paolo

    2016-03-15

    A novel approach for sorting exosomes from multiple myeloma (MM), monoclonal gammopathy of undetermined significance (MGUS) and healthy individuals is presented. The method is based on the combination of colloidal gold nanoplasmonics and surface plasmon resonance (SPR) biosensing and probes distinctive colloidal properties of MM-derived exosomes, such as molar concentration and cell membrane binding preferences. It allowed to discover that MM patients produce about four folds more exosomes than MGUS and healthy individuals. In addition, it showed that among the analyzed exosomes, only the MM-derived ones bind heparin - a structural analog of heparan sulfate proteoglycans known to mediate exosome endocytosis - with an apparent dissociation constant (Kd) equal to about 1 nM, indicating a high affinity binding. This plasmonic method complements the classical biochemical profiling approach to exosomes, expanding the MM biomarker panel and adding biosensors to the toolbox to diagnose MM. It may find applications for other diseases and has wider interest for fundamental and translational research involving exosomes. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Heparanase-2 and syndecan-1 in colon cancer: the ugly ducklings or the beautiful swans?

    PubMed

    Giordano, Ricardo José

    2008-08-01

    Syndecan expression, or the lack thereof by tumor cells, has been associated with poor prognosis in several types of cancer, including colorectal cancer. Syndecan is a heparan sulfate proteoglycan involved in tumor adhesion, invasion, and metastasis. In addition, the expression of the enzyme heparanase by cancer cells correlates with malignant transformation and metastasis. Given the prominent role of syndecan and heparanase in physiological and pathological processes, they are promising molecular targets in the development of diagnostic methods and drugs for cancer and other diseases. A study in this issue of the European Journal of Gastroenterology & Hepatology reports the expression of syndecan-1 (Syn-1) and HPA2 in human colorectal cancer samples. These results confirm earlier observations that Syn-1 is downregulated by colorectal carcinoma cells but raise questions about its prognostic value. This study is also the first report on the upregulation of HPA2 in human cancer samples. HPA2 and Syn-1 expression by colorectal cancer tumor cells and the possible implications in disease progression are discussed.

  3. Differential Activation of Acid Sphingomyelinase and Ceramide Release Determines Invasiveness of Neisseria meningitidis into Brain Endothelial Cells

    PubMed Central

    Simonis, Alexander; Hebling, Sabrina; Gulbins, Erich; Schneider-Schaulies, Sibylle; Schubert-Unkmeir, Alexandra

    2014-01-01

    The interaction with brain endothelial cells is central to the pathogenicity of Neisseria meningitidis infections. Here, we show that N. meningitidis causes transient activation of acid sphingomyelinase (ASM) followed by ceramide release in brain endothelial cells. In response to N. meningitidis infection, ASM and ceramide are displayed at the outer leaflet of the cell membrane and condense into large membrane platforms which also concentrate the ErbB2 receptor. The outer membrane protein Opc and phosphatidylcholine-specific phospholipase C that is activated upon binding of the pathogen to heparan sulfate proteoglycans, are required for N. meningitidis-mediated ASM activation. Pharmacologic or genetic ablation of ASM abrogated meningococcal internalization without affecting bacterial adherence. In accordance, the restricted invasiveness of a defined set of pathogenic isolates of the ST-11/ST-8 clonal complex into brain endothelial cells directly correlated with their restricted ability to induce ASM and ceramide release. In conclusion, ASM activation and ceramide release are essential for internalization of Opc-expressing meningococci into brain endothelial cells, and this segregates with invasiveness of N. meningitidis strains. PMID:24945304

  4. Human Synovial Lubricin Expresses Sialyl Lewis x Determinant and Has L-selectin Ligand Activity*

    PubMed Central

    Jin, Chunsheng; Ekwall, Anna-Karin Hultgård; Bylund, Johan; Björkman, Lena; Estrella, Ruby P.; Whitelock, John M.; Eisler, Thomas; Bokarewa, Maria; Karlsson, Niclas G.

    2012-01-01

    Lubricin (or proteoglycan 4 (PRG4)) is an abundant mucin-like glycoprotein in synovial fluid (SF) and a major component responsible for joint lubrication. In this study, it was shown that O-linked core 2 oligosaccharides (Galβ1–3(GlcNAcβ1–6)GalNAcα1-Thr/Ser) on lubricin isolated from rheumatoid arthritis SF contained both sulfate and fucose residues, and SF lubricin was capable of binding to recombinant L-selectin in a glycosylation-dependent manner. Using resting human polymorphonuclear granulocytes (PMN) from peripheral blood, confocal microscopy showed that lubricin coated circulating PMN and that it partly co-localized with L-selectin expressed by these cells. In agreement with this, activation-induced shedding of L-selectin also mediated decreased lubricin binding to PMN. It was also found that PMN recruited to inflamed synovial area and fluid in rheumatoid arthritis patients kept a coat of lubricin. These observations suggest that lubricin is able to bind to PMN via an L-selectin-dependent and -independent manner and may play a role in PMN-mediated inflammation. PMID:22930755

  5. A patient with Simpson-Golabi-Behmel syndrome, biliary cirrhosis and successful liver transplantation.

    PubMed

    Jedraszak, Guillaume; Girard, Muriel; Mellos, Antonio; Djeddi, Djamal-Dine; Chardot, Christophe; Vanrenterghem, Audrey; Moizard, Marie-Pierre; Gondry, Jean; Sevestre, Henri; Mathieu-Dramard, Michele; Lacaille, Florence; Demeer, Benedicte

    2014-03-01

    Simpson-Golabi-Behmel syndrome type 1 (SGBS1) -OMIM 312870- is a rare X-linked inherited overgrowth syndrome caused by a loss of function mutation in the GPC3 gene. Affected patients present a variable phenotype with pre- and post-natal macrosomia, distinctive facial dysmorphism, organomegaly, and multiple congenital anomalies. Intellectual disability is not constant. About 10% of patients have an increased risk of developing embryonic tumors in early childhood. Only one case of biliary disease has been described so far. GPC3 is localized on Xq26. It encodes for glypican 3, a heparan sulfate proteoglycan, which among its different known roles, negatively regulates liver regeneration and hepatocyte proliferation. This report concerns a male with a SGBS1, carrier of a GPC3 pathogenic mutation, and neonatal liver disease, who developed an early biliary cirrhosis. Together with the associated risk of cancer and developmental delay, liver transplantation was discussed and then successfully performed at the age of 19 months. A hypothesis on the role of GPC3 in the patient's liver disease is also proposed. © 2013 Wiley Periodicals, Inc.

  6. Integrating computational and chemical biology tools in the discovery of antiangiogenic small molecule ligands of FGF2 derived from endogenous inhibitors

    PubMed Central

    Foglieni, Chiara; Pagano, Katiuscia; Lessi, Marco; Bugatti, Antonella; Moroni, Elisabetta; Pinessi, Denise; Resovi, Andrea; Ribatti, Domenico; Bertini, Sabrina; Ragona, Laura; Bellina, Fabio; Rusnati, Marco; Colombo, Giorgio; Taraboletti, Giulia

    2016-01-01

    The FGFs/FGFRs system is a recognized actionable target for therapeutic approaches aimed at inhibiting tumor growth, angiogenesis, metastasis, and resistance to therapy. We previously identified a non-peptidic compound (SM27) that retains the structural and functional properties of the FGF2-binding sequence of thrombospondin-1 (TSP-1), a major endogenous inhibitor of angiogenesis. Here we identified new small molecule inhibitors of FGF2 based on the initial lead. A similarity-based screening of small molecule libraries, followed by docking calculations and experimental studies, allowed selecting 7 bi-naphthalenic compounds that bound FGF2 inhibiting its binding to both heparan sulfate proteoglycans and FGFR-1. The compounds inhibit FGF2 activity in in vitro and ex vivo models of angiogenesis, with improved potency over SM27. Comparative analysis of the selected hits, complemented by NMR and biochemical analysis of 4 newly synthesized functionalized phenylamino-substituted naphthalenes, allowed identifying the minimal stereochemical requirements to improve the design of naphthalene sulfonates as FGF2 inhibitors. PMID:27000667

  7. Drosophila Glypicans Regulate Follicle Stem Cell Maintenance and Niche Competition.

    PubMed

    Su, Tsu-Yi; Nakato, Eriko; Choi, Pui Yee; Nakato, Hiroshi

    2018-04-09

    Adult stem cells reside in specialized microenvironments, called niches, which provide signals for stem cells to maintain their undifferentiated and self-renewing state. To maintain stem cell quality, several types of stem cells are known to be regularly replaced by progenitor cells through niche competition. However, the cellular and molecular bases for stem cell competition for niche occupancy are largely unknown. Here, we show that two Drosophila members of the glypican family of heparan sulfate proteoglycans (HSPGs), Dally and Dally-like (Dlp), differentially regulate follicle stem cell (FSC) maintenance and FSC competitiveness for niche occupancy. Lineage analyses of glypican mutant FSC clones showed that dally is essential for normal FSC maintenance. In contrast, dlp is a hyper-competitive mutation: dlp mutant FSC progenitors often eventually occupy the entire epithelial sheet. RNAi knockdown experiments showed that Dally and Dlp play both partially redundant and distinct roles in regulating Jak/Stat, Wg and Hh signaling in FSCs. The Drosophila FSC system offers a powerful genetic model to study the mechanisms by which HSPGs exert specific functions in stem cell replacement and competition. Copyright © 2018, Genetics.

  8. Molecular characterization and transcriptional analysis of the female-enriched chondroitin proteoglycan 2 of Toxocara canis.

    PubMed

    Ma, G X; Zhou, R Q; Hu, L; Luo, Y L; Luo, Y F; Zhu, H H

    2018-03-01

    Toxocara canis is an important but neglected zoonotic parasite, and is the causative agent of human toxocariasis. Chondroitin proteoglycans are biological macromolecules, widely distributed in extracellular matrices, with a great diversity of functions in mammals. However, there is limited information regarding chondroitin proteoglycans in nematode parasites. In the present study, a female-enriched chondroitin proteoglycan 2 gene of T. canis (Tc-cpg-2) was cloned and characterized. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to measure the transcription levels of Tc-cpg-2 among tissues of male and female adult worms. A 485-amino-acid (aa) polypeptide was predicted from a continuous 1458-nuleotide open reading frame and designated as TcCPG2, which contains a 21-aa signal peptide. Conserved domain searching indicated three chitin-binding peritrophin-A (CBM_14) domains in the amino acid sequence of TcCPG2. Multiple alignment with the inferred amino acid sequences of Caenorhabditis elegans and Ascaris suum showed that CBM_14 domains were well conserved among these species. Phylogenetic analysis suggested that TcCPG2 was closely related to the sequence of chondroitin proteoglycan 2 of A. suum. Interestingly, a high level of Tc-cpg-2 was detected in female germline tissues, particularly in the oviduct, suggesting potential roles of this gene in reproduction (e.g. oogenesis and embryogenesis) of adult T. canis. The functional roles of Tc-cpg-2 in reproduction and development in this parasite and related parasitic nematodes warrant further functional studies.

  9. Structure of corneal layers, collagen fibrils, and proteoglycans of tree shrew cornea.

    PubMed

    Almubrad, Turki; Akhtar, Saeed

    2011-01-01

    The stroma is the major part of the cornea, in which collagen fibrils and proteoglycans are distributed uniformly. We describe the ultrastructure of corneal layers, collagen fibrils (CF), and proteoglycans (PGs) in the tree shrew cornea. Tree shrew corneas (5, 6, and 10 week old animals) and normal human corneas (24, 25, and 54 years old) were fixed in 2.5% glutaraldehyde containing cuprolinic blue in a sodium acetate buffer. The tissue was processed for electron microscopy. The 'iTEM Olympus Soft Imaging Solutions GmbH' program was used to measure the corneal layers, collagen fibril diameters and proteoglycan areas. The tree shrew cornea consists of 5 layers: the epithelium, Bowman's layer, stroma, Descemet's membrane, and endothelium. The epithelium was composed of squamous cells, wing cells and basal cells. The Bowman's layer was 5.5±1.0 µm thick and very similar to a normal human Bowman's layer. The stroma was 258±7.00 µm thick and consisted of collagen fibril lamellae. The lamellae were interlaced with one another in the anterior stroma, but ran parallel to one another in the middle and posterior stroma. Collagen fibrils were decorated with proteoglycan filaments with an area size of 390 ±438 nm(2). The collagen fibril had a minimum diameter of 39±4.25 nm. The interfibrillar spacing was 52.91±6.07 nm. Within the collagen fibrils, very small electron-dense particles were present. The structure of the tree shrew cornea is very similar to that of the normal human cornea. As is the case with the human cornea, the tree shrew cornea had a Bowman's layer, lamellar interlacing in the anterior stroma and electron-dense particles within the collagen fibrils. The similarities of the tree shrew cornea with the human cornea suggest that it could be a good structural model to use when studying changes in collagen fibrils and proteoglycans in non-genetic corneal diseases, such as ectasia caused after LASIK (laser-assisted in situ keratomileusis).

  10. Utilization of Glycosaminoglycans/Proteoglycans as Carriers for Targeted Therapy Delivery

    PubMed Central

    Misra, Suniti; Hascall, Vincent C.; Atanelishvili, Ilia; Moreno Rodriguez, Ricardo; Markwald, Roger R.; Ghatak, Shibnath

    2015-01-01

    The outcome of patients with cancer has improved significantly in the past decade with the incorporation of drugs targeting cell surface adhesive receptors, receptor tyrosine kinases, and modulation of several molecules of extracellular matrices (ECMs), the complex composite of collagens, glycoproteins, proteoglycans, and glycosaminoglycans that dictates tissue architecture. Cancer tissue invasive processes progress by various oncogenic strategies, including interfering with ECM molecules and their interactions with invasive cells. In this review, we describe how the ECM components, proteoglycans and glycosaminoglycans, influence tumor cell signaling. In particular this review describes how the glycosaminoglycan hyaluronan (HA) and its major receptor CD44 impact invasive behavior of tumor cells, and provides useful insight when designing new therapeutic strategies in the treatment of cancer. PMID:26448753

  11. Altered Liver Proteoglycan/Glycosaminoglycan Structure as a Manifestation of Extracellular Matrix Remodeling upon BCG-induced Granulomatosis in Mice.

    PubMed

    Kim, L B; Shkurupy, V A; Putyatina, A N

    2017-01-01

    Experimental BCG-induced granulomatosis in mice was used to study changes in the dynamics of individual liver proteoglycan components reflecting phasic extracellular matrix remodeling, determined by the host-parasite interaction and associated with granuloma development. In the early BCG-granulomatosis period, the increase in individual proteoglycan components promotes granuloma formation, providing conditions for mycobacteria adhesion to host cells, migration of phagocytic cells from circulation, and cell-cell interaction leading to granuloma development and fibrosis. Later, reduced reserve capacity of the extracellular matrix, development of interstitial fibrosis and granuloma fibrosis can lead to trophic shortage for cells within the granulomas, migration of macrophages out of them, and development of spontaneous necrosis and apoptosis typical of tuberculosis.

  12. Phase I studies of treatment of malignant gliomas and neoplastic meningitis with 131I-radiolabeled monoclonal antibodies anti-tenascin 81C6 and anti-chondroitin proteoglycan sulfate Me1-14 F (ab')2--a preliminary report.

    PubMed

    Bigner, D D; Brown, M; Coleman, R E; Friedman, A H; Friedman, H S; McLendon, R E; Bigner, S H; Zhao, X G; Wikstrand, C J; Pegram, C N

    1995-01-01

    The advent of monoclonal antibody (MAb) technology has made Ehrlich's postulate of the 'magic bullet' an attainable goal. Although specific localization of polyvalent antibodies to human gliomas was demonstrated in the 1960s, the lack of specific, high affinity antibody populations and of defined target antigens of sufficient density precluded therapeutic applications. Not until the identification of operationally specific tumor-associated antigens (present in tumor tissue but not normal central nervous system tissue); production of homogeneous, high affinity MAbs to such antigens; and the use of compartmental administration (intrathecal or intracystic), has the promise of passive immunotherapy of primary and metastatic central nervous system neoplasms been recognized. We report here preliminary data from Phase I studies of the compartmental administration of the anti-tenascin MAb 81C6 and F(ab2)2 fragments of MAb Me1-14, which recognizes the proteoglycan chondroitin sulfate-associated protein of gliomas and melanomas, to patients with primary central nervous system tumors or tumors metastatic to the central nervous system. Phase I dose escalation studies of intracystically administered 131I-labeled anti-tenascin MAb 81C6 to either spontaneous cysts of recurrent gliomas or surgically created cystic resection cavities have resulted in striking responses. Of five patients with recurrent cystic gliomas treated, four had partial responses, clinically or radiographically. Similarly, in patients with surgically created resection cavities, a partial response at the treatment site and extended stable disease status has been obtained following intracystic administration of 131I-labeled 81C6. No evidence of hematologic or neurologic toxicity has been observed in either patient population, with the exception of transient exacerbation of a pre-existing seizure disorder in a single patient. Dosimetry calculations indicated high intracystic retention for four to six weeks with little or no systemic dissemination; estimated total doses intracystically ranged from 12,700-70,290 rad. Intrathecal administration of labeled MAbs to patients with neoplastic meningitis is more difficult to assess in terms of clinical responsiveness. Of patients so treated with either 131I-labeled 81C6 or 131I-labeled Me1-14 (F(ab)2, cerebrospinal fluid and radiographic responses have been achieved, and survival prolongation through maintenance of stable disease has been observed in several cases. Initial results from pHase I dose escalation trials are encouraging in terms of the proportion of cases of disease stabilization and partial and complete responses obtained. Importantly, neurotoxicity has been virtually nonexistent, and hematologic toxicity rare and rapidly responsive to treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

  13. Murine T cell activation is regulated by surfen (bis-2-methyl-4-amino-quinolyl-6-carbamide)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Warford, Jordan, E-mail: jordan.warford@dal.ca; Doucette, Carolyn D., E-mail: carolyn.doucette@dal.ca; Hoskin, David W., E-mail: d.w.hoskin@dal.ca

    2014-01-10

    Highlights: •Surfen is the first inhibitor of glycosaminoglycan function to be studied in murine T cells. •Surfen reduces T cell proliferation stimulated in vitro and in vivo. •Surfen reduces CD25 expression in T cells activated in vivo but not in vitro. •Surfen increases T cell proliferation when T cell receptor activation is bypassed. •Surfen’s effects are blocked by co-administration of heparin sulfate. -- Abstract: Surfen (bis-2-methyl-4-amino-quinolyl-6-carbamide) binds to glycosaminoglycans (GAGs) and has been shown to influence their function, and the function of proteoglycans (complexes of GAGs linked to a core protein). T cells synthesize, secrete and express GAGs and proteoglycansmore » which are involved in several aspects of T cell function. However, there are as yet no studies on the effect of GAG-binding agents such as surfen on T cell function. In this study, surfen was found to influence murine T cell activation. Doses between 2.5 and 20 μM produced a graduated reduction in the proliferation of T cells activated with anti-CD3/CD28 antibody-coated T cell expander beads. Surfen (20 mg/kg) was also administered to mice treated with anti-CD3 antibody to activate T cells in vivo. Lymphocytes from surfen-treated mice also showed reduced proliferation and lymph node cell counts were reduced. Surfen reduced labeling with a cell viability marker (7-ADD) but to a much lower extent than its effect on proliferation. Surfen also reduced CD25 (the α-subunit of the interleukin (IL)-2 receptor) expression with no effect on CD69 expression in T cells treated in vivo but not in vitro. When receptor activation was bypassed by treating T cells in vitro with phorbyl myristate acetate (10 ng/ml) and ionomycin (100 ng/ml), surfen treatment either increased proliferation (10 μM) or had no effect (2.5, 5 and 20 μM). In vitro treatment of T cells with surfen had no effect on IL-2 or interferon-γ synthesis and did not alter proliferation of the IL-2 dependent cell line CTLL-2. The effect of surfen was antagonized dose-dependently by co-treatment with heparin sulfate. We conclude that surfen inhibits T cell proliferation in vitro and in vivo. When T cell receptor-driven activation is bypassed surfen had a neutral or stimulatory effect on T cell proliferation. The results imply that endogenous GAGs and proteoglycans play a complex role in promoting or inhibiting different aspects of T cell activation.« less

  14. Salmon cartilage proteoglycan suppresses mouse experimental colitis through induction of Foxp3{sup +} regulatory T cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mitsui, Toshihito; Department of Digestive Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori 036-8562; Sashinami, Hiroshi

    Research highlights: {yields} Salmon proteoglycan suppresses IL-10{sup -/-} cell transfer-induced colitis progression. {yields} Salmon proteoglycan suppresses Th1- and Th17-related factors in colitis mice. {yields} Salmon proteoglycan enhances Foxp3 expression. -- Abstract: Proteoglycans (PGs) are complex glycohydrates which are widely distributed in extracellular matrix (ECM). PGs are involved in the construction of ECM, cell proliferation and differentiation. ECM components are involved in transduction of proinflammatory responses, but it is still unknown whether PGs are involved in inflammatory response. In this study, we investigated the effect of PG extracted from salmon cartilage on the progression of experimental colitis-induced in severe combined immunodeficiencymore » mice by cell transfer from interleukin-10 (IL-10){sup -/-} mice. IL-10{sup -/-} cell-transferred mice showed weight loss, colon shortening and histological appearance of mild colitis. Daily oral administration of PG attenuated the clinical progression of colitis in a dose-dependent manner. Colitis-induced mice showed the elevated expression of IFN-{gamma}, IL-12, TNF-{alpha}, IL-21, IL-23p19, IL-6, IL-17A and retinoic acid-related orphan receptor {gamma}t (ROR{gamma}t) in lamina propria mononuclear cells (LPMCs) and oral administration of PG suppressed the expression of these factors. Conversely, expression of Foxp3 that induces CD4{sup +}CD25{sup +} regulatory T cells in LPMCs was enhanced by PG administration. These findings suggested that salmon PG attenuated the progression of colitis due to suppression of inflammatory response by enhancement of regulatory T cell induction.« less

  15. Soybean-fragmented proteoglycans against skin aging.

    PubMed

    Barba, Clara; Alonso, Cristina; Sánchez, Isabel; Suñer, Elisa; Sáez-Martín, L C; Coderch, Luisa

    2017-08-01

    The majority of age-dependent skin changes happen in the dermis layer inducing changes in skin collagen and in the proteoglycans. The main aim of this work is to study the efficacy of a Proteum serum, containing soybean-fragmented proteoglycans, against skin aging. In vitro tests were performed to evaluate the Proteum serum ability on activating the production of collagen and proteoglycans. An in vivo long-term study was performed to determine the efficacy of the Proteum serum when applied on skin. Protection of healthy skin against detergent-induced dermatitis and the antioxidant properties of the applied Proteum serum were also studied. The in vitro tests demonstrated that the Proteum serum was able to elevate the production of molecules which are essential for supporting the dermal extracellular matrix organization. These results were correlated by the in vivo measurements where a clear trend on improving the measured skin parameters due to the Proteum serum application was found. A beneficial effect of the Proteum serum was demonstrated with an improvement in the skin roughness and a reinforcement of the skin barrier function. Moreover, a significant protector effect on human stratum corneum against lipids peroxides (LPO) was demonstrated.

  16. Apple procyanidins promote mitochondrial biogenesis and proteoglycan biosynthesis in chondrocytes.

    PubMed

    Masuda, Isao; Koike, Masato; Nakashima, Shohei; Mizutani, Yu; Ozawa, Yusuke; Watanabe, Kenji; Sawada, Yoko; Sugiyama, Hiroshi; Sugimoto, Atsushi; Nojiri, Hidetoshi; Sashihara, Koichi; Yokote, Koutaro; Shimizu, Takahiko

    2018-05-08

    Apples are well known to have various benefits for the human body. Procyanidins are a class of polyphenols found in apples that have demonstrated effects on the circulatory system and skeletal organs. Osteoarthritis (OA) is a locomotive syndrome that is histologically characterized by cartilage degeneration associated with the impairment of proteoglycan homeostasis in chondrocytes. However, no useful therapy for cartilage degeneration has been developed to date. In the present study, we detected beneficial effects of apple polyphenols or their procyanidins on cartilage homeostasis. An in vitro assay revealed that apple polyphenols increased the activities of mitochondrial dehydrogenases associated with an increased copy number of mitochondrial DNA as well as the gene expression of peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC-1α), suggesting the promotion of PGC-1α-mediated mitochondrial biogenesis. Apple  procyanidins also enhanced proteoglycan biosynthesis with aggrecan upregulation in primary chondrocytes. Of note, oral treatment with apple procyanidins prevented articular cartilage degradation in OA model mice induced by mitochondrial dysfunction in chondrocytes. Our findings suggest that apple procyanidins are promising food components that inhibit OA progression by promoting mitochondrial biogenesis and proteoglycan homeostasis in chondrocytes.

  17. Thrombin-mediated proteoglycan synthesis utilizes both protein-tyrosine kinase and serine/threonine kinase receptor transactivation in vascular smooth muscle cells.

    PubMed

    Burch, Micah L; Getachew, Robel; Osman, Narin; Febbraio, Mark A; Little, Peter J

    2013-03-08

    G protein-coupled receptor signaling is mediated by three main mechanisms of action; these are the classical pathway, β-arrestin scaffold signaling, and the transactivation of protein-tyrosine kinase receptors such as those for EGF and PDGF. Recently, it has been demonstrated that G protein-coupled receptors can also mediate signals via transactivation of serine/threonine kinase receptors, most notably the transforming growth factor-β receptor family. Atherosclerosis is characterized by the development of lipid-laden plaques in blood vessel walls. Initiation of plaque development occurs via low density lipoprotein retention in the neointima of vessels due to binding with modified proteoglycans secreted by vascular smooth muscle cells. Here we show that transactivation of protein-tyrosine kinase receptors is mediated by matrix metalloproteinase triple membrane bypass signaling. In contrast, serine/threonine kinase receptor transactivation is mediated by a cytoskeletal rearrangement-Rho kinase-integrin system, and both protein-tyrosine kinase and serine/threonine kinase receptor transactivation concomitantly account for the total proteoglycan synthesis stimulated by thrombin in vascular smooth muscle. This work provides evidence of thrombin-mediated proteoglycan synthesis and paves the way for a potential therapeutic target for plaque development and atherosclerosis.

  18. Structure of corneal layers, collagen fibrils, and proteoglycans of tree shrew cornea

    PubMed Central

    Almubrad, Turki

    2011-01-01

    Purpose The stroma is the major part of the cornea, in which collagen fibrils and proteoglycans are distributed uniformly. We describe the ultrastructure of corneal layers, collagen fibrils (CF), and proteoglycans (PGs) in the tree shrew cornea. Methods Tree shrew corneas (5, 6, and 10 week old animals) and normal human corneas (24, 25, and 54 years old) were fixed in 2.5% glutaraldehyde containing cuprolinic blue in a sodium acetate buffer. The tissue was processed for electron microscopy. The ‘iTEM Olympus Soft Imaging Solutions GmbH’ program was used to measure the corneal layers, collagen fibril diameters and proteoglycan areas. Results The tree shrew cornea consists of 5 layers: the epithelium, Bowman’s layer, stroma, Descemet’s membrane, and endothelium. The epithelium was composed of squamous cells, wing cells and basal cells. The Bowman’s layer was 5.5±1.0 µm thick and very similar to a normal human Bowman’s layer. The stroma was 258±7.00 µm thick and consisted of collagen fibril lamellae. The lamellae were interlaced with one another in the anterior stroma, but ran parallel to one another in the middle and posterior stroma. Collagen fibrils were decorated with proteoglycan filaments with an area size of 390 ±438 nm2. The collagen fibril had a minimum diameter of 39±4.25 nm. The interfibrillar spacing was 52.91±6.07 nm. Within the collagen fibrils, very small electron-dense particles were present. Conclusions The structure of the tree shrew cornea is very similar to that of the normal human cornea. As is the case with the human cornea, the tree shrew cornea had a Bowman's layer, lamellar interlacing in the anterior stroma and electron-dense particles within the collagen fibrils. The similarities of the tree shrew cornea with the human cornea suggest that it could be a good structural model to use when studying changes in collagen fibrils and proteoglycans in non-genetic corneal diseases, such as ectasia caused after LASIK (laser-assisted in situ keratomileusis). PMID:21921979

  19. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Martin, Emily B.; Williams, Angela; Heidel, Eric

    Highlights: •Polybasic peptide p5 binds human light chain amyloid extracts. •The binding of p5 with amyloid involves both glycosaminoglycans and fibrils. •Heparinase treatment led to a correlation between p5 binding and fibril content. •p5 binding to AL amyloid requires electrostatic interactions. -- Abstract: In previously published work, we have described heparin-binding synthetic peptides that preferentially recognize amyloid deposits in a mouse model of reactive systemic (AA) amyloidosis and can be imaged by using positron and single photon emission tomographic imaging. We wanted to extend these findings to the most common form of visceral amyloidosis, namely light chain (AL); however, theremore » are no robust experimental animal models of AL amyloidosis. To further define the binding of the lead peptide, p5, to AL amyloid, we characterized the reactivity in vitro of p5 with in situ and patient-derived AL amyloid extracts which contain both hypersulfated heparan sulfate proteoglycans as well as amyloid fibrils. Histochemical staining demonstrated that the peptide specifically localized with tissue-associated AL amyloid deposits. Although we anticipated that p5 would undergo electrostatic interactions with the amyloid-associated glycosaminoglycans expressing heparin-like side chains, no significant correlation between peptide binding and glycosaminoglycan content within amyloid extracts was observed. In contrast, following heparinase I treatment, although overall binding was reduced, a positive correlation between peptide binding and amyloid fibril content became evident. This interaction was further confirmed using synthetic light chain fibrils that contain no carbohydrates. These data suggest that p5 can bind to both the sulfated glycosaminoglycans and protein fibril components of AL amyloid. Understanding these complex electrostatic interactions will aid in the optimization of synthetic peptides for use as amyloid imaging agents and potentially as therapeutics for the treatment of amyloid diseases.« less

  20. A chondroitin sulfate chain attached to the bone dentin matrix protein 1 NH2-terminal fragment.

    PubMed

    Qin, Chunlin; Huang, Bingzhen; Wygant, James N; McIntyre, Bradley W; McDonald, Charles H; Cook, Richard G; Butler, William T

    2006-03-24

    Dentin matrix protein 1 (DMP1) is an acidic noncollagenous protein shown by gene ablations to be critical for the proper mineralization of bone and dentin. In the extracellular matrix of these tissues DMP1 is present as fragments representing the NH2-terminal (37 kDa) and COOH-terminal (57 kDa) portions of the cDNA-deduced amino acid sequence. During our separation of bone noncollagenous proteins, we observed a high molecular weight, DMP1-related component (designated DMP1-PG). We purified DMP1-PG with a monoclonal anti-DMP1 antibody affinity column. Amino acid analysis and Edman degradation of tryptic peptides proved that the core protein for DMP1-PG is the 37-kDa fragment of DMP1. Chondroitinase treatments demonstrated that the slower migration rate of DMP1-PG is due to the presence of glycosaminoglycan. Quantitative disaccharide analysis indicated that the glycosaminoglycan is made predominantly of chondroitin 4-sulfate. Further analysis on tryptic peptides led us to conclude that a single glycosaminoglycan chain is linked to the core protein via Ser74, located in the Ser74-Gly75 dipeptide, an amino acid sequence specific for the attachment of glycosaminoglycans. Our findings show that in addition to its existence as a phosphoprotein, the NH2-terminal fragment from DMP1 occurs as a proteoglycan. Amino acid sequence alignment analysis showed that the Ser74-Gly75 dipeptide and its flanking regions are highly conserved among a wide range of species from caiman to the Homo sapiens, indicating that this glycosaminoglycan attachment domain has survived an extremely long period of evolution pressure, suggesting that the glycosaminoglycan may be critical for the basic biological functions of DMP1.

  1. Fibroblast Growth Factor-based Signaling through Synthetic Heparan Sulfate Blocks Copolymers Studied Using High Cell Density Three-dimensional Cell Printing*

    PubMed Central

    Sterner, Eric; Masuko, Sayaka; Li, Guoyun; Li, Lingyun; Green, Dixy E.; Otto, Nigel J.; Xu, Yongmei; DeAngelis, Paul L.; Liu, Jian; Dordick, Jonathan S.; Linhardt, Robert J.

    2014-01-01

    Four well-defined heparan sulfate (HS) block copolymers containing S-domains (high sulfo group content) placed adjacent to N-domains (low sulfo group content) were chemoenzymatically synthesized and characterized. The domain lengths in these HS block co-polymers were ∼40 saccharide units. Microtiter 96-well and three-dimensional cell-based microarray assays utilizing murine immortalized bone marrow (BaF3) cells were developed to evaluate the activity of these HS block co-polymers. Each recombinant BaF3 cell line expresses only a single type of fibroblast growth factor receptor (FGFR) but produces neither HS nor fibroblast growth factors (FGFs). In the presence of different FGFs, BaF3 cell proliferation showed clear differences for the four HS block co-polymers examined. These data were used to examine the two proposed signaling models, the symmetric FGF2-HS2-FGFR2 ternary complex model and the asymmetric FGF2-HS1-FGFR2 ternary complex model. In the symmetric FGF2-HS2-FGFR2 model, two acidic HS chains bind in a basic canyon located on the top face of the FGF2-FGFR2 protein complex. In this model the S-domains at the non-reducing ends of the two HS proteoglycan chains are proposed to interact with the FGF2-FGFR2 protein complex. In contrast, in the asymmetric FGF2-HS1-FGFR2 model, a single HS chain interacts with the FGF2-FGFR2 protein complex through a single S-domain that can be located at any position within an HS chain. Our data comparing a series of synthetically prepared HS block copolymers support a preference for the symmetric FGF2-HS2-FGFR2 ternary complex model. PMID:24563485

  2. Glucosamine Hydrochloride but Not Chondroitin Sulfate Prevents Cartilage Degradation and Inflammation Induced by Interleukin-1α in Bovine Cartilage Explants

    PubMed Central

    Bascoul-Colombo, Cécile; Garaiova, Iveta; Plummer, Sue F.; Harwood, John L.; Caterson, Bruce; Hughes, Clare E

    2016-01-01

    Objective Glucosamine hydrochloride (GH) and chondroitin sulfate (CS) are commonly used for the treatment of osteoarthritis (OA). The aim of this study was to assess their effects, alone and in combination, on preventing aggrecan degradation and inflammation in an in vitro model of OA. Design To test the effects of GH and/or CS as a preventative treatment, cartilage explants were pretreated with the compound(s) using concentrations that showed no detrimental effect on chondrocyte viability. Interleukin-1α (IL-1α) was added to induce cartilage degradation, supernatant and explants were analyzed for proteoglycan degradation products, aggrecanase mRNA expression and activity, and for the release of inflammatory markers. Results Following treatment with IL-1α, 2 mg/mL dose of GH pretreatment was associated with a reduction of glycosaminoglycan release, reduced generation of the pathological interglobular domain aggrecan catabolites, decreased mRNA levels of ADAMTS-4 and -5 and reduced activity of ADAMTS-4. In contrast, CS alone did not have a significant effect on IL-1α-induced cartilage degradation and the addition of 0.4 mg/mL CS to 2 mg/mL GH did not further inhibit IL-1α-induced activity. Pretreatment with 2 mg/mL GH also reduced the release of inflammatory markers, prostaglandin E2 and nitric oxide induced by IL-1α while CS did not have a significant effect. Conclusions The results suggest that GH prevents cartilage degradation mediated by aggrecanases ADAMTS-4 and -5, and may also reduce inflammation. This could be part of the mechanisms by which GH is effective in maintaining joint integrity and function, and preventing or delaying early symptoms of OA. PMID:26958319

  3. Genome-wide siRNA screen reveals a new cellular partner of NK cell receptor KIR2DL4: heparan sulfate directly modulates KIR2DL4-mediated responses

    PubMed Central

    Brusilovsky, Michael; Cordoba, Moti; Rosental, Benyamin; Hershkovitz, Oren; Andrake, Mark D.; Pecherskaya, Anna; Einarson, Margret B.; Zhou, Yan; Braiman, Alex

    2013-01-01

    KIR2DL4 (CD158d) is a distinct member of the killer cell Ig-like receptor (KIR) family in human NK cells that can induce cytokine production and cytolytic activity in resting NK cells. Soluble HLA-G, normally expressed only by fetal-derived trophoblast cells, was reported to be a ligand for KIR2DL4; however, KIR2DL4 expression is not restricted to the placenta and can be found in CD56high subset of peripheral blood NK cells. We demonstrated that KIR2DL4 can interact with alternative ligand(s), expressed by cells of epithelial or fibroblast origin. A genome-wide high-throughput siRNA screen revealed that KIR2DL4 recognition of cells surface ligand(s) is directly regulated by heparan sulfate (HS) glucosamine 3-O-sulfotransferase 3B1 (HS3ST3B1). KIR2DL4 was found to directly interact with HS/heparin, and the D0-domain of KIR2DL4 was essential for this interaction. Accordingly, exogenous HS/heparin can regulate cytokine production by KIR2DL4-expressing NK cells and HEK293T cells (HEK293T-2DL4) and induces differential localization of KIR2DL4 to rab5+ and rab7+ endosomes, thus leading to down-regulation of cytokine production and degradation of the receptor. Furthermore, we showed that intimate interaction of syndecan-4 (SDC4) HS Proteo-Glycan (HSPG) and KIR2DL4 directly affects receptor endocytosis and membrane trafficking. PMID:24127555

  4. Newly generated heparanase knock-out mice unravel co-regulation of heparanase and matrix metalloproteinases.

    PubMed

    Zcharia, Eyal; Jia, Juan; Zhang, Xiao; Baraz, Lea; Lindahl, Ulf; Peretz, Tamar; Vlodavsky, Israel; Li, Jin-Ping

    2009-01-01

    Heparanase, a mammalian endo-beta-D-glucuronidase, specifically degrades heparan sulfate proteoglycans ubiquitously associated with the cell surface and extracellular matrix. This single gene encoded enzyme is over-expressed in most human cancers, promoting tumor metastasis and angiogenesis. We report that targeted disruption of the murine heparanase gene eliminated heparanase enzymatic activity, resulting in accumulation of long heparan sulfate chains. Unexpectedly, the heparanase knockout (Hpse-KO) mice were fertile, exhibited a normal life span and did not show prominent pathological alterations. The lack of major abnormalities is attributed to a marked elevation in the expression of matrix metalloproteinases, for example, MMP2 and MMP14 in the Hpse-KO liver and kidney. Co-regulation of heparanase and MMPs was also noted by a marked decrease in MMP (primarily MMP-2,-9 and 14) expression following transfection and over-expression of the heparanase gene in cultured human mammary carcinoma (MDA-MB-231) cells. Immunostaining (kidney tissue) and chromatin immunoprecipitation (ChIP) analysis (Hpse-KO mouse embryonic fibroblasts) suggest that the newly discovered co-regulation of heparanase and MMPs is mediated by stabilization and transcriptional activity of beta-catenin. The lack of heparanase expression and activity was accompanied by alterations in the expression level of MMP family members, primarily MMP-2 and MMP-14. It is conceivable that MMP-2 and MMP-14, which exert some of the effects elicited by heparanase (i.e., over branching of mammary glands, enhanced angiogenic response) can compensate for its absence, in spite of their different enzymatic substrate. Generation of viable Hpse-KO mice lacking significant abnormalities may provide a promising indication for the use of heparanase as a target for drug development.

  5. MDA-MB-231 breast cancer cell viability, motility and matrix adhesion are regulated by a complex interplay of heparan sulfate, chondroitin-/dermatan sulfate and hyaluronan biosynthesis.

    PubMed

    Viola, Manuela; Brüggemann, Kathrin; Karousou, Evgenia; Caon, Ilaria; Caravà, Elena; Vigetti, Davide; Greve, Burkhard; Stock, Christian; De Luca, Giancarlo; Passi, Alberto; Götte, Martin

    2017-06-01

    Proteoglycans and glycosaminoglycans modulate numerous cellular processes relevant to tumour progression, including cell proliferation, cell-matrix interactions, cell motility and invasive growth. Among the glycosaminoglycans with a well-documented role in tumour progression are heparan sulphate, chondroitin/dermatan sulphate and hyaluronic acid/hyaluronan. While the mode of biosynthesis differs for sulphated glycosaminoglycans, which are synthesised in the ER and Golgi compartments, and hyaluronan, which is synthesized at the plasma membrane, these polysaccharides partially compete for common substrates. In this study, we employed a siRNA knockdown approach for heparan sulphate (EXT1) and heparan/chondroitin/dermatan sulphate-biosynthetic enzymes (β4GalT7) in the aggressive human breast cancer cell line MDA-MB-231 to study the impact on cell behaviour and hyaluronan biosynthesis. Knockdown of β4GalT7 expression resulted in a decrease in cell viability, motility and adhesion to fibronectin, while these parameters were unchanged in EXT1-silenced cells. Importantly, these changes were associated with a decreased expression of syndecan-1, decreased signalling response to HGF and an increase in the synthesis of hyaluronan, due to an upregulation of the hyaluronan synthases HAS2 and HAS3. Interestingly, EXT1-depleted cells showed a downregulation of the UDP-sugar transporter SLC35D1, whereas SLC35D2 was downregulated in β4GalT7-depleted cells, indicating an intricate regulatory network that connects all glycosaminoglycans synthesis. The results of our in vitro study suggest that a modulation of breast cancer cell behaviour via interference with heparan sulphate biosynthesis may result in a compensatory upregulation of hyaluronan biosynthesis. These findings have important implications for the development of glycosaminoglycan-targeted therapeutic approaches for malignant diseases.

  6. Anatomically Discrete Sex Differences in Neuroplasticity in Zebra Finches as Reflected by Perineuronal Nets

    PubMed Central

    Cornez, Gilles; ter Haar, Sita M.; Cornil, Charlotte A.; Balthazart, Jacques

    2015-01-01

    Large morphological sex differences in the vertebrate brain were initially identified in song control nuclei of oscines. Besides gross differences between volumes of nuclei in males and females, sex differences also concern the size and dendritic arborization of neurons and various neurochemical markers, such as the calcium-binding protein parvalbumin (PV). Perineuronal nets (PNN) of the extracellular matrix are aggregates of different compounds, mainly chondroitin sulfate proteoglycans, that surround subsets of neurons, often expressing PV. PNN develop in zebra finches song control nuclei around the end of the sensitive period for song learning and tutor deprivation, known to delay the end of the song learning sensitive period, decreases the numbers of PNN in HVC. We demonstrate here the existence in zebra finches of a major sex difference (males > females) affecting the number of PNN (especially those surrounding PV-positive cells) in HVC and to a smaller extent the robust nucleus of the arcopallium, RA, the two main nuclei controlling song production. These differences were not present in Area X and LMAN, the lateral magnocellular nucleus of the anterior nidopallium. A dense expression of material immunoreactive for chondroitin sulfate was also detected in several nuclei of the auditory and visual pathways. This material was often organized in perineuronal rings but quantification of these PNN did not reveal any sex difference with the exception that the percentage of PNN surrounding PV-ir cells in the dorsal lateral mesencephalic nucleus, MLd, was larger in females than in males, a sex difference in the opposite direction compared to what is seen in HVC and RA. These data confirm and extend previous studies demonstrating the sex difference affecting PNN in HVC-RA by showing that this sex difference is anatomically specific and does not concern visual or auditory pathways. PMID:25848776

  7. Characterization of hyaluronate binding proteins isolated from 3T3 and murine sarcoma virus transformed 3T3 cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Turley, E.A.; Moore, D.; Hayden, L.J.

    1987-06-02

    A hyaluronic acid binding fraction was purified from the supernatant media of both 3T3 and murine sarcoma virus (MSV) transformed 3T3 cultures by hyaluronate and immunoaffinity chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis resolved the hyaluronate affinity-purified fraction into three major protein bands of estimated molecular weight (M/sub r,e/) 70K, 66K, and 56K which contained hyaluronate binding activity and which were termed hyaluronate binding proteins (HABP). Hyaluronate affinity chromatography combined with immunoaffinity chromatography, using antibody directed against the larger HABP, allowed a 20-fold purification of HABP. Fractions isolated from 3T3 supernatant medium also contained additional binding molecules in the molecular weightmore » range of 20K. This material was present in vanishingly small amounts and was not detected with a silver stain or with (/sup 35/S)methionine label. The three protein species isolated by hyaluronate affinity chromatography (M/sub r,e/ 70K, 66K, and 56K) were related to one another since they shared antigenic determinants and exhibited similar pI values. In isocratic conditions, HABP occurred as aggregates of up to 580 kilodaltons. Their glycoprotein nature was indicated by their incorporation of /sup 3/H-sugars. Enzyme-linked immunoadsorbent assay showed they were antigenically distinct from other hyaluronate binding proteins such as fibronectin, cartilage link protein, and the hyaluronate binding region of chondroitin sulfate proteoglycan. The results are discussed with regard both to the functional significance of hyaluronate-cell surface interactions in transformed as well as normal cells and to the relationship of HABP to other reported hyaluronate binding proteins.« less

  8. Effects of chondroitin sulfate and interleukin-1beta on human chondrocyte cultures exposed to pressurization: a biochemical and morphological study.

    PubMed

    Nerucci, F; Fioravanti, A; Cicero, M R; Collodel, G; Marcolongo, R

    2000-07-01

    Objective This study investigated the in vitro effects of chondroitin sulfate (CS) on human articular chondrocytes cultivated in the presence or in the absence of interleukin-1beta (IL-1beta) during 10 days of culture with and without pressurization cycles. Design The effects of CS (10 and 100 microg/ml) with and without IL-1beta were assessed in the culture medium of cells exposed to pressurization cycles in the form of synusoidal waves (minimum pressure 1 Mpa, maximum pressure 5 Mpa) and a frequency of 0.25 Hz for 3 h by immunoenzymatic method on microplates for the quantitative measurement of human proteoglycans (PG). On the 4th and 10th day of culture the cells were used for morphological analysis by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Results The presence of IL-1beta determines a significant decrease in PG concentration measured in the culture medium. When the cells are cultured in the presence of IL-1beta and CS, a statistically significant restoration of PG levels is observed. Under pressurization conditions, we observed that PG concentration in the medium of cells presents a significant increase at baseline conditions, in the presence of IL-1beta+CS10 and IL-1beta+CS100, but not with IL-1beta alone. The results concerning metabolic evaluation are confirmed by the morphologic findings obtained by TEM and SEM. Conclusions These in vitro studies confirm the protective role of CS, which counteracts the IL-1beta induced effects and they confirm the importance of pressure on chondrocyte metabolism and morphology.

  9. Generation of a Close-to-Native In Vitro System to Study Lung Cells-Extracellular Matrix Crosstalk.

    PubMed

    Garlíková, Zuzana; Silva, Ana Catarina; Rabata, Anas; Potěšil, David; Ihnatová, Ivana; Dumková, Jana; Koledová, Zuzana; Zdráhal, Zbyněk; Vinarský, Vladimír; Hampl, Aleš; Pinto-do-Ó, Perpétua; Nascimento, Diana Santos

    2018-01-01

    Extracellular matrix (ECM) is an essential component of the tissue microenvironment, actively shaping cellular behavior. In vitro culture systems are often poor in ECM constituents, thus not allowing for naturally occurring cell-ECM interactions. This study reports on a straightforward and efficient method for the generation of ECM scaffolds from lung tissue and its subsequent in vitro application using primary lung cells. Mouse lung tissue was subjected to decellularization with 0.2% sodium dodecyl sulfate, hypotonic solutions, and DNase. Resultant ECM scaffolds were devoid of cells and DNA, whereas lung ECM architecture of alveolar region and blood and airway networks were preserved. Scaffolds were predominantly composed of core ECM and ECM-associated proteins such as collagens I-IV, nephronectin, heparan sulfate proteoglycan core protein, and lysyl oxidase homolog 1, among others. When homogenized and applied as coating substrate, ECM supported the attachment of lung fibroblasts (LFs) in a dose-dependent manner. After ECM characterization and biocompatibility tests, a novel in vitro platform for three-dimensional (3D) matrix repopulation that permits live imaging of cell-ECM interactions was established. Using this system, LFs colonized the ECM scaffolds, displaying a close-to-native morphology in intimate interaction with the ECM fibers, and showed nuclear translocation of the mechanosensor yes-associated protein (YAP), when compared with cells cultured in two dimensions. In conclusion, we developed a 3D-like culture system, by combining an efficient decellularization method with a live-imaging culture platform, to replicate in vitro native lung cell-ECM crosstalk. This is a valuable system that can be easily applied to other organs for ECM-related drug screening, disease modeling, and basic mechanistic studies.

  10. Suppression of amyloid beta A11 antibody immunoreactivity by vitamin C: possible role of heparan sulfate oligosaccharides derived from glypican-1 by ascorbate-induced, nitric oxide (NO)-catalyzed degradation.

    PubMed

    Cheng, Fang; Cappai, Roberto; Ciccotosto, Giuseppe D; Svensson, Gabriel; Multhaup, Gerd; Fransson, Lars-Åke; Mani, Katrin

    2011-08-05

    Amyloid β (Aβ) is generated from the copper- and heparan sulfate (HS)-binding amyloid precursor protein (APP) by proteolytic processing. APP supports S-nitrosylation of the HS proteoglycan glypican-1 (Gpc-1). In the presence of ascorbate, there is NO-catalyzed release of anhydromannose (anMan)-containing oligosaccharides from Gpc-1-nitrosothiol. We investigated whether these oligosaccharides interact with Aβ during APP processing and plaque formation. anMan immunoreactivity was detected in amyloid plaques of Alzheimer (AD) and APP transgenic (Tg2576) mouse brains by immunofluorescence microscopy. APP/APP degradation products detected by antibodies to the C terminus of APP, but not Aβ oligomers detected by the anti-Aβ A11 antibody, colocalized with anMan immunoreactivity in Tg2576 fibroblasts. A 50-55-kDa anionic, sodium dodecyl sulfate-stable, anMan- and Aβ-immunoreactive species was obtained from Tg2576 fibroblasts using immunoprecipitation with anti-APP (C terminus). anMan-containing HS oligo- and disaccharide preparations modulated or suppressed A11 immunoreactivity and oligomerization of Aβ42 peptide in an in vitro assay. A11 immunoreactivity increased in Tg2576 fibroblasts when Gpc-1 autoprocessing was inhibited by 3-β[2(diethylamino)ethoxy]androst-5-en-17-one (U18666A) and decreased when Gpc-1 autoprocessing was stimulated by ascorbate. Neither overexpression of Gpc-1 in Tg2576 fibroblasts nor addition of copper ion and NO donor to hippocampal slices from 3xTg-AD mice affected A11 immunoreactivity levels. However, A11 immunoreactivity was greatly suppressed by the subsequent addition of ascorbate. We speculate that temporary interaction between the Aβ domain and small, anMan-containing oligosaccharides may preclude formation of toxic Aβ oligomers. A portion of the oligosaccharides are co-secreted with the Aβ peptides and deposited in plaques. These results support the notion that an inadequate supply of vitamin C could contribute to late onset AD in humans.

  11. Chondroitinase C Selectively Degrades Chondroitin Sulfate Glycosaminoglycans that Inhibit Axonal Growth within the Endoneurium of Peripheral Nerve.

    PubMed

    Graham, James B; Muir, David

    2016-01-01

    The success of peripheral nerve regeneration is highly dependent on the regrowth of axons within the endoneurial basal lamina tubes that promote target-oriented pathfinding and appropriate reinnervation. Restoration of nerve continuity at this structural level after nerve transection injury by direct repair and nerve grafting remains a major surgical challenge. Recently, biological approaches that alter the balance of growth inhibitors and promoters in nerve have shown promise to improve appropriate axonal regeneration and recovery of peripheral nerve function. Chondroitin sulfate proteoglycans (CSPGs) are known inhibitors of axonal growth. This growth inhibition is mainly associated with a CSPG's glycosaminoglycan chains. Enzymatic degradation of these chains with chondroitinase eliminates this inhibitory activity and, when applied in vivo, can improve the outcome of nerve repair. To date, these encouraging findings were obtained with chondroitinase ABC (a pan-specific chondroitinase). The aim of this study was to examine the distribution of CSPG subtypes in rodent, rabbit, and human peripheral nerve and to test more selective biological enzymatic approaches to improve appropriate axonal growth within the endoneurium and minimize aberrant growth. Here we provide evidence that the endoneurium, but not the surrounding epineurium, is rich in CSPGs that have glycosaminoglycan chains readily degraded by chondroitinase C. Biochemical studies indicate that chondroitinase C has degradation specificity for 6-sulfated glycosaminoglycans found in peripheral nerve. We found that chondroitinase C degrades and inactivates inhibitory CSPGs within the endoneurium but not so much in the surrounding nerve compartments. Cryoculture bioassays (neurons grown on tissue sections) show that chondroitinase C selectively and significantly enhanced neuritic growth associated with the endoneurial basal laminae without changing growth-inhibiting properties of the surrounding epineurium. Interestingly, chondroitinase ABC treatment increased greatly the growth-promoting properties of the epineurial tissue whereas chondroitinase C had little effect. Our evidence indicates that chondroitinase C effectively degrades and inactivates inhibitory CSPGs present in the endoneurial Schwann cell basal lamina and does so more specifically than chondroitinase ABC. These findings are discussed in the context of improving nerve repair and regeneration and the growth-promoting properties of processed nerve allografts.

  12. Proteoglycan 4: A Dynamic Regulator of Skeletogenesis and Parathyroid Hormone Skeletal Anabolism

    PubMed Central

    Novince, Chad M; Michalski, Megan N; Koh, Amy J; Sinder, Benjamin P; Entezami, Payam; Eber, Matthew R; Pettway, Glenda J; Rosol, Thomas J; Wronski, Thomas J; Kozloff, Ken M; McCauley, Laurie K

    2014-01-01

    Proteoglycan 4 (Prg4), known for its lubricating and protective actions in joints, is a strong candidate regulator of skeletal homeostasis and parathyroid hormone (PTH) anabolism. Prg4 is a PTH-responsive gene in bone and liver. Prg4 null mutant mice were used to investigate the impact of proteoglycan 4 on skeletal development, remodeling, and PTH anabolic actions. Young Prg4 mutant and wild-type mice were administered intermittent PTH(1–34) or vehicle daily from 4 to 21 days. Young Prg4 mutant mice had decreased growth plate hypertrophic zones, trabecular bone, and serum bone formation markers versus wild-type mice, but responded with a similar anabolic response to PTH. Adult Prg4 mutant and wild-type mice were administered intermittent PTH(1–34) or vehicle daily from 16 to 22 weeks. Adult Prg4 mutant mice had decreased trabecular and cortical bone, and blunted PTH-mediated increases in bone mass. Joint range of motion and animal mobility were lower in adult Prg4 mutant versus wild-type mice. Adult Prg4 mutant mice had decreased marrow and liver fibroblast growth factor 2 (FGF-2) mRNA and reduced serum FGF-2, which were normalized by PTH. A single dose of PTH decreased the PTH/PTHrP receptor (PPR), and increased Prg4 and FGF-2 to a similar extent in liver and bone. Proteoglycan 4 supports endochondral bone formation and the attainment of peak trabecular bone mass, and appears to support skeletal homeostasis indirectly by protecting joint function. Bone- and liver-derived FGF-2 likely regulate proteoglycan 4 actions supporting trabeculae formation. Blunted PTH anabolic responses in adult Prg4 mutant mice are associated with altered biomechanical impact secondary to joint failure. PMID:21932346

  13. Tec-kinase-mediated phosphorylation of fibroblast growth factor 2 is essential for unconventional secretion.

    PubMed

    Ebert, Antje D; Laussmann, Mareike; Wegehingel, Sabine; Kaderali, Lars; Erfle, Holger; Reichert, Jürgen; Lechner, Johannes; Beer, Hans-Dietmar; Pepperkok, Rainer; Nickel, Walter

    2010-06-01

    Fibroblast growth factor 2 (FGF2) is a potent mitogen that is exported from cells by an endoplasmic reticulum (ER)/Golgi-independent mechanism. Unconventional secretion of FGF2 occurs by direct translocation across plasma membranes, a process that depends on the phosphoinositide phosphatidylinositol 4,5-biphosphate (PI(4,5)P(2)) at the inner leaflet as well as heparan sulfate proteoglycans at the outer leaflet of plasma membranes; however, additional core and regulatory components of the FGF2 export machinery have remained elusive. Here, using a highly effective RNAi screening approach, we discovered Tec kinase as a novel factor involved in unconventional secretion of FGF2. Tec kinase does not affect FGF2 secretion by an indirect mechanism, but rather forms a heterodimeric complex with FGF2 resulting in phosphorylation of FGF2 at tyrosine 82, a post-translational modification shown to be essential for FGF2 membrane translocation to cell surfaces. Our findings suggest a crucial role for Tec kinase in regulating FGF2 secretion under various physiological conditions and, therefore, provide a new perspective for the development of a novel class of antiangiogenic drugs targeting the formation of the FGF2/Tec complex.

  14. Cell-Surface Bound Nonreceptors and Signaling Morphogen Gradients

    PubMed Central

    Wan, Frederic Y.M.

    2013-01-01

    The patterning of many developing tissues is orchestrated by gradients of signaling morphogens. Included among the molecular events that drive the formation of morphogen gradients are a variety of elaborate regulatory interactions. Such interactions are thought to make gradients robust, i.e. insensitive to change in the face of genetic or environmental perturbations. But just how this is accomplished is a major unanswered question. Recently extensive numerical simulations suggest that robustness of signaling gradients can be achieved through morphogen degradation mediated by cell surface bound non-signaling receptor molecules (or nonreceptors for short) such as heparan sulfate proteoglycans (HSPG). The present paper provides a mathematical validation of the results from the aforementioned numerical experiments. Extension of a basic extracellular model to include reversible binding with nonreceptors synthesized at a prescribed rate and mediated morphogen degradation shows that the signaling gradient diminishes with increasing concentration of cell-surface nonreceptors. Perturbation and asymptotic solutions obtained for i) low (receptor and nonreceptor) occupancy, and ii) high nonreceptor concntration permit more explicit delineation of the effects of nonreceptors on signaling gradients and facilitate the identification of scenarios in which the presence of nonreceptors may or may not be effective in promoting robustness. PMID:25232201

  15. Adeno-associated virus-2 and its primary cellular receptor-Cryo-EM structure of a heparin complex

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O'Donnell, Jason; Taylor, Kenneth A.; Chapman, Michael S.

    2009-03-15

    Adeno-associated virus serotype 2 (AAV-2) is a leading candidate vector for gene therapy. Cell entry starts with attachment to a primary receptor, Heparan Sulfate Proteoglycan (HSPG) before binding to a co-receptor. Here, cryo-electron microscopy provides direct visualization of the virus-HSPG interactions. Single particle analysis was performed on AAV-2 complexed with a 17 kDa heparin fragment at 8.3 A resolution. Heparin density covers the shoulder of spikes surrounding viral 3-fold symmetry axes. Previously implicated, positively charged residues R{sub 448/585}, R{sub 451/588} and R{sub 350/487} from another subunit cluster at the center of the heparin footprint. The footprint is much more extensivemore » than apparent through mutagenesis, including R{sub 347/484}, K{sub 395/532} and K{sub 390/527} that are more conserved, but whose roles have been controversial. It also includes much of a region proposed as a co-receptor site, because prior studies had not revealed heparin interactions. Heparin density bridges over the viral 3-fold axes, indicating multi-valent attachment to symmetry-related binding sites.« less

  16. Deposition of insoluble elastin by pulmonary fibroblasts from patients with COPD is increased by treatment with versican siRNA.

    PubMed

    Wu, Lian; Zhang, Jing; Qu, Jie Ming; Bai, Chun-Xue; Merrilees, Mervyn J

    2017-01-01

    A reduced content of alveolar elastic fibers is a key feature of COPD lung. Despite continued elastogenic potential by alveolar fibroblasts in the lung affected by COPD, repair of elastic fibers does not take place, which is due to increased levels of the chondroitin sulfate proteoglycan versican that inhibits the assembly of tropoelastin into fibers. In this study, primary pulmonary fibroblast cell lines from COPD and non-COPD patients were treated with a small interfering RNA (siRNA) against versican to determine if knockdown of versican could restore the deposition of insoluble elastin. Versican siRNA treatment reduced versican expression and secretion by pulmonary fibroblasts from both COPD and non-COPD patients ( P <0.01) and significantly increased deposition of insoluble elastin in the COPD cell cultures ( P <0.05). The treatment, however, did not significantly affect production of soluble elastin (tropoelastin) in either the COPD or non-COPD cell cultures, supporting a role for versican in inhibiting assembly but not synthesis of tropoelastin. These results suggest that removal or knockdown of versican may be a possible therapeutic strategy for increasing deposition of insoluble elastin and stimulating repair of elastic fibers in COPD lung.

  17. Lipoprotein lipase-dependent binding and uptake of low density lipoproteins by THP-1 monocytes and macrophages: possible involvement of lipid rafts.

    PubMed

    Makoveichuk, Elena; Castel, Susanna; Vilaró, Senen; Olivecrona, Gunilla

    2004-11-08

    Lipoprotein lipase (LPL) is produced by cells in the artery wall and can mediate binding of lipoproteins to cell surface heparan sulfate proteoglycans (HSPG), resulting in endocytosis (the bridging function). Active, dimeric LPL may dissociate to inactive monomers, the main form found in plasma. We have studied binding/internalization of human low density lipoprotein (LDL), mediated by bovine LPL, using THP-1 monocytes and macrophages. Uptake of (125)I-LDL was similar in monocytes and macrophages and was not affected by the LDL-receptor family antagonist receptor-associated protein (RAP) or by the phagocytosis inhibitor cytochalasin D. In contrast, uptake depended on HSPG and on membrane cholesterol. Incubation in the presence of dexamethasone increased the endogenous production of LPL by the cells and also increased LPL-mediated binding of LDL to the cell surfaces. Monomeric LPL was bound to the cells mostly in a heparin-resistant fashion. We conclude that the uptake of LDL mediated by LPL dimers is receptor-independent and involves cholesterol-enriched membrane areas (lipid rafts). Dimeric and monomeric LPL differ in their ability to mediate binding/uptake of LDL, probably due to different mechanisms for binding/internalization.

  18. Extracellular matrix controls neuronal features that mediate the persistence of fear.

    PubMed

    Pignataro, Annabella; Pagano, Roberto; Guarneri, Giorgia; Middei, Silvia; Ammassari-Teule, Martine

    2017-12-01

    Degradation of the chondroitin sulfate proteoglycans of the extracellular matrix (ECM) by injections of the bacterial enzyme chondroitinase ABC (ChABC) in the basolateral amygdala (BLA) does not impair fear memory formation but accelerates its extinction and disrupts its reactivation. These observations suggest that the treatment might selectively interfere with the post-extinction features of neurons that mediate the reinstatement of fear. Here, we report that ChABC mice show regular fear memory and memory-driven c-fos activation and dendritic spine formation in the BLA. These mice then rapidly extinguish their fear response and exhibit a post-extinction concurrent reduction in c-fos activation and large dendritic spines that extends to the anterior cingulate cortex 7 days later. At this remote time point, fear renewal and fear retrieval are impaired. These findings show that a non-cellular component of the brain tissue controls post-extinction levels of neuronal activity and spine enlargement in the regions sequentially remodelled during the formation of recent and remote fear memory. By preventing BLA and aCC neurons to retain neuronal features that serve to reactivate an extinguished fear memory, ECM digestion might offer a therapeutic strategy for durable attenuation of traumatic memories.

  19. Raman spectroscopic investigation of spinal cord injury in a rat model

    NASA Astrophysics Data System (ADS)

    Saxena, Tarun; Deng, Bin; Stelzner, Dennis; Hasenwinkel, Julie; Chaiken, Joseph

    2011-02-01

    Raman spectroscopy was used to study temporal molecular changes associated with spinal cord injury (SCI) in a rat model. Raman spectra of saline-perfused, injured, and healthy rat spinal cords were obtained and compared. Two injury models, a lateral hemisection and a moderate contusion were investigated. The net fluorescence and the Raman spectra showed clear differences between the injured and healthy spinal cords. Based on extensive histological and biochemical characterization of SCI available in the literature, these differences were hypothesized to be due to cell death, demyelination, and changes in the extracellular matrix composition, such as increased expression of proteoglycans and hyaluronic acid, at the site of injury where the glial scar forms. Further, analysis of difference spectra indicated the presence of carbonyl containing compounds, hypothesized to be products of lipid peroxidation and acid catalyzed hydrolysis of glycosaminoglycan moieties. These results compared well with in vitro experiments conducted on chondroitin sulfate sugars. Since the glial scar is thought to be a potent biochemical barrier to nerve regeneration, this observation suggests the possibility of using near infrared Raman spectroscopy to study injury progression and explore potential treatments ex vivo, and ultimately monitor potential remedial treatments within the spinal cord in vivo.

  20. Agrin Signalling Contributes to Cell Activation and Is Overexpressed in T Lymphocytes from Lupus Patients1

    PubMed Central

    Jury, Elizabeth C.; Eldridge, Jillian; Isenberg, David A.; Kabouridis, Panagiotis S.

    2008-01-01

    It is shown in this study that the heparan sulfate proteoglycan agrin is overexpressed in T cells isolated from patients with the autoimmune disease systemic lupus erythematosus (SLE). Freshly isolated CD4+ and CD8+ subpopulations both exhibited higher expression over healthy controls, which however, gradually declined when cells were cultured in vitro. Agrin expression was induced following in vitro activation of cells via their Ag receptor, or after treatment with IFN-α, a cytokine shown to be pathogenic in lupus. Furthermore, serum from SLE patients with active disease was able to induce agrin expression when added to T cells from healthy donors, an increase that was partially blocked by neutralizing anti-IFN-α Abs. Cross-linking agrin with mAbs resulted in rapid reorganization of the actin cytoskeleton, activation of the ERK MAPK cascade, and augmentation of anti-CD3-induced proliferation and IL-10 production, indicating that agrin is a functional receptor in T cells. These results demonstrate that agrin expression in human T cells is regulated by cell activation and IFN-α, and may have an important function during cell activation with potential implications for autoimmunity. PMID:18025246

  1. Crystal Structure of the Agrin-Responsive Immunoglobulin-like Domains 1 and 2 of the Receptor Tyrosine Kinase MuSK

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stiegler,A.; Burden, S.; Hubbard, S.

    Muscle-specific kinase (MuSK) is a receptor tyrosine kinase expressed exclusively in skeletal muscle, where it is required for formation of the neuromuscular junction. MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. Here, we report the crystal structure of the agrin-responsive first and second immunoglobulin-like domains (Ig1 and Ig2) of the MuSK ectodomain at 2.2 {angstrom} resolution. The structure reveals that MuSK Ig1 and Ig2 are Ig-like domains of the I-set subfamily, which are configured in a linear, semi-rigid arrangement. In addition to the canonical internal disulfide bridge, Ig1 contains a second, solvent-exposed disulfide bridge, which our biochemical datamore » indicate is critical for proper folding of Ig1 and processing of MuSK. Two Ig1-2 molecules form a non-crystallographic dimer that is mediated by a unique hydrophobic patch on the surface of Ig1. Biochemical analyses of MuSK mutants introduced into MuSK{sup -/-} myotubes demonstrate that residues in this hydrophobic patch are critical for agrin-induced MuSK activation.« less

  2. Collagen 18 and agrin are secreted by neural crest cells to remodel their microenvironment and regulate their migration during enteric nervous system development.

    PubMed

    Nagy, Nandor; Barad, Csilla; Hotta, Ryo; Bhave, Sukhada; Arciero, Emily; Dora, David; Goldstein, Allan M

    2018-05-08

    The enteric nervous system (ENS) arises from neural crest cells that migrate, proliferate, and differentiate into enteric neurons and glia within the intestinal wall. Many extracellular matrix (ECM) components are present in the embryonic gut, but their role in regulating ENS development is largely unknown. Here, we identify heparan sulfate proteoglycan proteins, including collagen XVIII (Col18) and agrin, as important regulators of enteric neural crest-derived cell (ENCDC) development. In developing avian hindgut, Col18 is expressed at the ENCDC wavefront, while agrin expression occurs later. Both proteins are normally present around enteric ganglia, but are absent in aganglionic gut. Using chick-mouse intestinal chimeras and enteric neurospheres, we show that vagal- and sacral-derived ENCDCs from both species secrete Col18 and agrin. Whereas glia express Col18 and agrin, enteric neurons only express the latter. Functional studies demonstrate that Col18 is permissive whereas agrin is strongly inhibitory to ENCDC migration, consistent with the timing of their expression during ENS development. We conclude that ENCDCs govern their own migration by actively remodeling their microenvironment through secretion of ECM proteins. © 2018. Published by The Company of Biologists Ltd.

  3. Target cell cyclophilins facilitate human papillomavirus type 16 infection.

    PubMed

    Bienkowska-Haba, Malgorzata; Patel, Hetalkumar D; Sapp, Martin

    2009-07-01

    Following attachment to primary receptor heparan sulfate proteoglycans (HSPG), human papillomavirus type 16 (HPV16) particles undergo conformational changes affecting the major and minor capsid proteins, L1 and L2, respectively. This results in exposure of the L2 N-terminus, transfer to uptake receptors, and infectious internalization. Here, we report that target cell cyclophilins, peptidyl-prolyl cis/trans isomerases, are required for efficient HPV16 infection. Cell surface cyclophilin B (CyPB) facilitates conformational changes in capsid proteins, resulting in exposure of the L2 N-terminus. Inhibition of CyPB blocked HPV16 infection by inducing noninfectious internalization. Mutation of a putative CyP binding site present in HPV16 L2 yielded exposed L2 N-terminus in the absence of active CyP and bypassed the need for cell surface CyPB. However, this mutant was still sensitive to CyP inhibition and required CyP for completion of infection, probably after internalization. Taken together, these data suggest that CyP is required during two distinct steps of HPV16 infection. Identification of cell surface CyPB will facilitate the study of the complex events preceding internalization and adds a putative drug target for prevention of HPV-induced diseases.

  4. LDL receptor-related protein mediates cell-surface clustering and hepatic sequestration of chylomicron remnants in LDLR-deficient mice.

    PubMed

    Yu, K C; Chen, W; Cooper, A D

    2001-06-01

    It has been proposed that in the liver, chylomicron remnants (lipoproteins carrying dietary lipid) may be sequestered before being internalized by hepatocytes. To study this, chylomicron remnants labeled with a fluorescent dye were perfused into isolated livers of LDL receptor-deficient (LDLR-deficient) mice (Ldlr(-/-)) and examined by confocal microscopy. In contrast to livers from normal mice, there was clustering of the chylomicron remnants on the cell surface in the space of DISSE: These remnant clusters colocalized with clusters of LDLR-related protein (LRP) and could be eliminated by low concentrations of receptor-associated protein, an inhibitor of LRP. When competed with ligands of heparan sulfate proteoglycans (HSPGs), the remnant clusters still appeared but were fewer in number, although syndecans (membrane HSPGs) colocalized with the remnant clusters. This suggests that the clustering of remnants is not dependent on syndecans but that the syndecans may modify the binding of remnants. These results establish that sequestration is a novel process, the clustering of remnants in the space of DISSE: The clustering involves remnants binding to the LRP, and this may be stabilized by binding with syndecans, eventually followed by endocytosis.

  5. The role of novel chitin-like polysaccharides in Alzheimer disease.

    PubMed

    Castellani, Rudy J; Perry, George; Smith, Mark A

    2007-12-01

    While controversy over the role of carbohydrates in amyloidosis has existed since the initial recognition of amyloid, current understanding of the role of polysaccharides in the pathogenesis of amyloid deposition of Alzheimer disease and other amyloidoses is limited to studies of glyco-conjugates such as heparin sulfate proteoglycan. We hypothesized that polysaccharides may play a broader role in light of 1) the impaired glucose utilization in Alzheimer disease; 2) the demonstration of amylose in the Alzheimer disease brain; 3) the role of amyloid in Alzheimer disease pathogenesis. Specifically, as with glucose polymers (amyloid), we wanted to explore whether glucosamine polymers such as chitin were being synthesized and deposited as a result of impaired glucose utilization and aberrant hexosamine pathway activation. To this end, using calcofluor histochemistry, we recently demonstrated that amyloid plaques and blood vessels affected by amyloid angiopathy in subjects with sporadic and familial Alzheimer disease elicit chitin-type characteristics. Since chitin is a highly insoluble molecule and a substrate for glycan-protein interactions, chitin-like polysaccharides within the Alzheimer disease brain could provide a scaffolding for amyloid-beta deposition. As such, glucosamine may facilitate the process of amyloidosis, and /or provide neuroprotection in the Alzheimer disease brain.

  6. A Newly Defined Area of the Mouse Anterior Hypothalamus Involved in Septohypothalamic Circuit: Perifornical Area of the Anterior Hypothalamus, PeFAH.

    PubMed

    Horii-Hayashi, Noriko; Nishi, Mayumi

    2018-02-27

    Although the hypothalamus is classified into more than 10 compartments, it still contains uncharacterized areas. In this study, we identified a new triangular-shaped area between the paraventricular hypothalamic nucleus (PVN) and the fornix area in the mouse anterior hypothalamus, which is enriched in chondroitin sulfate proteoglycans (CSPGs). We designated this region as the perifornical area of the anterior hypothalamus (PeFAH) based on its anatomical location. As evidenced by Nissl staining, the PeFAH was distinguishable as an area of relatively low density. Immunohistochemical and DNA microarray analyses indicated that PeFAH contains sparsely distributed calretinin-positive neurons and densely clustered enkephalin-positive neurons. Furthermore, the PeFAH was shown to have bidirectional neural connections with the lateral septum. Indeed, we confirmed enkephalinergic projections from PeFAH neurons to the lateral septum, and inversely, calbindin-positive lateral septum neurons as afferents to the PeFAH. Finally, c-Fos expression analysis revealed that the activity of certain PeFAH neuronal populations tended to be increased by psychological stressors, but not that of enkephalinergic neurons. We proposed PeFAH as a new region in the AH.

  7. Syndecan-1 Is Required to Maintain Intradermal Fat and Prevent Cold Stress

    PubMed Central

    Wollny, Damian; Clark, Rod J.; Roopra, Avtar; Colman, Ricki J.; MacDougald, Ormond A.; Shedd, Timothy A.; Nelson, David W.; Yen, Mei-I; Yen, Chi-Liang Eric; Alexander, Caroline M.

    2014-01-01

    Homeostatic temperature regulation is fundamental to mammalian physiology and is controlled by acute and chronic responses of local, endocrine and nervous regulators. Here, we report that loss of the heparan sulfate proteoglycan, syndecan-1, causes a profoundly depleted intradermal fat layer, which provides crucial thermogenic insulation for mammals. Mice without syndecan-1 enter torpor upon fasting and show multiple indicators of cold stress, including activation of the stress checkpoint p38α in brown adipose tissue, liver and lung. The metabolic phenotype in mutant mice, including reduced liver glycogen, is rescued by housing at thermoneutrality, suggesting that reduced insulation in cool temperatures underlies the observed phenotypes. We find that syndecan-1, which functions as a facultative lipoprotein uptake receptor, is required for adipocyte differentiation in vitro. Intradermal fat shows highly dynamic differentiation, continuously expanding and involuting in response to hair cycle and ambient temperature. This physiology probably confers a unique role for Sdc1 in this adipocyte sub-type. The PPARγ agonist rosiglitazone rescues Sdc1−/− intradermal adipose tissue, placing PPARγ downstream of Sdc1 in triggering adipocyte differentiation. Our study indicates that disruption of intradermal adipose tissue development results in cold stress and complex metabolic pathology. PMID:25101993

  8. Broad-spectrum non-toxic antiviral nanoparticles with a virucidal inhibition mechanism

    NASA Astrophysics Data System (ADS)

    Cagno, Valeria; Andreozzi, Patrizia; D'Alicarnasso, Marco; Jacob Silva, Paulo; Mueller, Marie; Galloux, Marie; Le Goffic, Ronan; Jones, Samuel T.; Vallino, Marta; Hodek, Jan; Weber, Jan; Sen, Soumyo; Janeček, Emma-Rose; Bekdemir, Ahmet; Sanavio, Barbara; Martinelli, Chiara; Donalisio, Manuela; Rameix Welti, Marie-Anne; Eleouet, Jean-Francois; Han, Yanxiao; Kaiser, Laurent; Vukovic, Lela; Tapparel, Caroline; Král, Petr; Krol, Silke; Lembo, David; Stellacci, Francesco

    2018-02-01

    Viral infections kill millions yearly. Available antiviral drugs are virus-specific and active against a limited panel of human pathogens. There are broad-spectrum substances that prevent the first step of virus-cell interaction by mimicking heparan sulfate proteoglycans (HSPG), the highly conserved target of viral attachment ligands (VALs). The reversible binding mechanism prevents their use as a drug, because, upon dilution, the inhibition is lost. Known VALs are made of closely packed repeating units, but the aforementioned substances are able to bind only a few of them. We designed antiviral nanoparticles with long and flexible linkers mimicking HSPG, allowing for effective viral association with a binding that we simulate to be strong and multivalent to the VAL repeating units, generating forces (~190 pN) that eventually lead to irreversible viral deformation. Virucidal assays, electron microscopy images, and molecular dynamics simulations support the proposed mechanism. These particles show no cytotoxicity, and in vitro nanomolar irreversible activity against herpes simplex virus (HSV), human papilloma virus, respiratory syncytial virus (RSV), dengue and lenti virus. They are active ex vivo in human cervicovaginal histocultures infected by HSV-2 and in vivo in mice infected with RSV.

  9. Heparanase expression in periapical granulomas and radicular cysts.

    PubMed

    Elad, S; Sherman, Y; Palmon, A; Vlodavsky, I; Or, R

    2013-01-01

    Heparanase is an endo-β-D-glucuronidase enzyme which degrades heparan sulfate glycosaminoglycan side chains of proteoglycans in the extracellular matrix and in basement membranes. The aim of this study was to evaluate the expression of heparanase in periapical granulomas (PGs) and radicular cysts (RCs). Immunohistochemistry was used to assess heparanase expression in PGs and RCs. Parameters including stain intensity, location and cell type were used to characterize heparanase expression in the periapical lesions. Ordered categories (from weak to strong) were used to compare the level of heparanase staining in the PG and RC groups. Both epithelial cells and inflammatory cells were positive for heparanase. The relative staining of the epithelial cells was strong, whereas the relative staining of the inflammatory cells was weak. Significant differences in immunohistochemical staining of epithelial cells were observed between RCs and PGs (p = 0.002). The relative expression of heparanase in epithelial cells in RCs was strong. In PGs, lesions with few or no epithelial cells, heparanase was predominantly expressed weakly by inflammatory cells. PGs and RCs have the same infectious origin. Therefore, the different cellular sources of heparanase in these periapical lesions may imply that this enzyme has specific pathogenetic functions in RCs and PGs.

  10. Delivery of Alginate Scaffold Releasing Two Trophic Factors for Spinal Cord Injury Repair

    PubMed Central

    Grulova, I.; Slovinska, L.; Blaško, J.; Devaux, S.; Wisztorski, M.; Salzet, M.; Fournier, I.; Kryukov, O.; Cohen, S.; Cizkova, D.

    2015-01-01

    Spinal cord injury (SCI) has been implicated in neural cell loss and consequently functional motor and sensory impairment. In this study, we propose an alginate -based neurobridge enriched with/without trophic growth factors (GFs) that can be utilized as a therapeutic approach for spinal cord repair. The bioavailability of key GFs, such as Epidermal Growth factor (EGF) and basic Fibroblast Growth Factor (bFGF) released from injected alginate biomaterial to the central lesion site significantly enhanced the sparing of spinal cord tissue and increased the number of surviving neurons (choline acetyltransferase positive motoneurons) and sensory fibres. In addition, we document enhanced outgrowth of corticospinal tract axons and presence of blood vessels at the central lesion. Tissue proteomics was performed at 3, 7 and 10 days after SCI in rats indicated the presence of anti-inflammatory factors in segments above the central lesion site, whereas in segments below, neurite outgrowth factors, inflammatory cytokines and chondroitin sulfate proteoglycan of the lectican protein family were overexpressed. Collectively, based on our data, we confirm that functional recovery was significantly improved in SCI groups receiving alginate scaffold with affinity-bound growth factors (ALG +GFs), compared to SCI animals without biomaterial treatment. PMID:26348665

  11. The Extract of Roots of Sophora flavescens Enhances the Recovery of Motor Function by Axonal Growth in Mice with a Spinal Cord Injury.

    PubMed

    Tanabe, Norio; Kuboyama, Tomoharu; Kazuma, Kohei; Konno, Katsuhiro; Tohda, Chihiro

    2015-01-01

    Although axonal extension to reconstruct spinal tracts should be effective for restoring function after spinal cord injury (SCI), chondroitin sulfate proteoglycan (CSPG) levels increase at spinal cord lesion sites, and inhibit axonal regrowth. In this study, we found that the water extract of roots of Sophora flavescens extended the axons of mouse cortical neurons, even on a CSPG-coated surface. Consecutive oral administrations of S. flavescens extract to SCI mice for 31 days increased the density of 5-HT-positive axons at the lesion site and improved the motor function. Further, the active constituents in the S. flavescens extract were identified. The water and alkaloid fractions of the S. flavescens extract each exhibited axonal extension activity in vitro. LC/MS analysis revealed that these fractions mainly contain matrine and/or oxymatrine, which are well-known major compounds in S. flavescens. Matrine and oxymatrine promoted axonal extension on the CSPG-coated surface. This study is the first to demonstrate that S. flavescens extract, matrine, and oxymatrine enhance axonal growth in vitro, even on a CSPG-coated surface, and that S. flavescens extract improves motor function and increases axonal density in SCI mice.

  12. The vascular basement membrane in the healthy and pathological brain.

    PubMed

    Thomsen, Maj S; Routhe, Lisa J; Moos, Torben

    2017-10-01

    The vascular basement membrane contributes to the integrity of the blood-brain barrier (BBB), which is formed by brain capillary endothelial cells (BCECs). The BCECs receive support from pericytes embedded in the vascular basement membrane and from astrocyte endfeet. The vascular basement membrane forms a three-dimensional protein network predominantly composed of laminin, collagen IV, nidogen, and heparan sulfate proteoglycans that mutually support interactions between BCECs, pericytes, and astrocytes. Major changes in the molecular composition of the vascular basement membrane are observed in acute and chronic neuropathological settings. In the present review, we cover the significance of the vascular basement membrane in the healthy and pathological brain. In stroke, loss of BBB integrity is accompanied by upregulation of proteolytic enzymes and degradation of vascular basement membrane proteins. There is yet no causal relationship between expression or activity of matrix proteases and the degradation of vascular matrix proteins in vivo. In Alzheimer's disease, changes in the vascular basement membrane include accumulation of Aβ, composite changes, and thickening. The physical properties of the vascular basement membrane carry the potential of obstructing drug delivery to the brain, e.g. thickening of the basement membrane can affect drug delivery to the brain, especially the delivery of nanoparticles.

  13. Syndecan-2 regulates melanin synthesis via protein kinase C βII-mediated tyrosinase activation.

    PubMed

    Jung, Hyejung; Chung, Heesung; Chang, Sung Eun; Choi, Sora; Han, Inn-Oc; Kang, Duk-Hee; Oh, Eok-Soo

    2014-05-01

    Syndecan-2, a transmembrane heparan sulfate proteoglycan that is highly expressed in melanoma cells, regulates melanoma cell functions (e.g. migration). Since melanoma is a malignant tumor of melanocytes, which largely function to synthesize melanin, we investigated the possible involvement of syndecan-2 in melanogenesis. Syndecan-2 expression was increased in human skin melanoma tissues compared with normal skin. In both mouse and human melanoma cells, siRNA-mediated knockdown of syndecan-2 was associated with reduced melanin synthesis, whereas overexpression of syndecan-2 increased melanin synthesis. Similar effects were also detected in human primary epidermal melanocytes. Syndecan-2 expression did not affect the expression of tyrosinase, a key enzyme in melanin synthesis, but instead enhanced the enzymatic activity of tyrosinase by increasing the membrane and melanosome localization of its regulator, protein kinase CβII. Furthermore, UVB caused increased syndecan-2 expression, and this up-regulation of syndecan-2 was required for UVB-induced melanin synthesis. Taken together, these data suggest that syndecan-2 regulates melanin synthesis and could be a potential therapeutic target for treating melanin-associated diseases. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Bovine lactoferricin induces TIMP-3 via the ERK1/2-Sp1 axis in human articular chondrocytes

    PubMed Central

    Yan, Dongyao; Chen, Di; Hawse, John R; van Wijnen, Andre J; Im, Hee-Jeong

    2013-01-01

    Bovine lactoferricin (LfcinB) is a heparan sulfate-binding peptide with multiple bioactivities. In human articular cartilage, LfcinB antagonizes interleukin-1 β (IL-1β) and fibroblast growth factor 2 (FGF-2) in proteoglycan metabolism, catabolic protease expression, and induction of pro-inflammatory mediators. LfcinB specifically activates ERK1/2, p38 and Akt, but whether these signaling pathways control the expression of LfcinB target genes remained unknown. In this report, we characterized a novel aspect of LfcinB-mediated genetic response in human articular chondrocytes, tissue inhibitor of metalloproteinase 3 (TIMP-3) induction. Inhibition of individual signaling pathways revealed that ERK1/2 functions as the major pathway in TIMP-3 expression, whereas Akt plays a minor role. Further investigation identified Sp1 as a critical transcriptional activator in TIMP-3 regulation, and Sp1 activity is modulated by ERK1/2, not Akt. Comparative quantification indicates significant downregulation of TIMP-3 occurs in OA chondrocytes, suggesting a beneficial role of LfcinB in OA pathogenesis. Our results collectively provide new insights into the mechanism of action of LfcinB, and support the candidacy of LfcinB as a chondroprotective agent. PMID:23313877

  15. Bone Proteoglycan Changes During Skeletal Unloading

    NASA Technical Reports Server (NTRS)

    Yamauchi, M.; Uzawa, K.; Pornprasertsuk, S.; Arnaud, S.; Grindeland, R.; Grzesik, W.

    1999-01-01

    Skeletal adaptability to mechanical loads is well known since the last century. Disuse osteopenia due to the microgravity environment is one of the major concerns for space travelers. Several studies have indicated that a retardation of the mineralization process and a delay in matrix maturation occur during the space flight. Mineralizing fibrillar type I collagen possesses distinct cross-linking chemistries and their dynamic changes during mineralization correlate well with its function as a mineral organizer. Our previous studies suggested that a certain group of matrix proteoglycans in bone play an inhibitory role in the mineralization process through their interaction with collagen. Based on these studies, we hypothesized that the altered mineralization during spaceflight is due in part to changes in matrix components secreted by cells in response to microgravity. In this study, we employed hindlimb elevation (tail suspension) rat model to study the effects of skeletal unloading on matrix proteoglycans in bone.

  16. Developmental alcohol exposure leads to a persistent change on astrocyte secretome

    PubMed Central

    Trindade, P; Hampton, B; Manhães, AC; Medina, AE

    2016-01-01

    Fetal alcohol spectrum disorder (FASD) is the most common cause of mental disabilities in the western world. It has been quite established that acute alcohol exposure can dramatically affect astrocyte function. Because the effects of early alcohol exposure on cell physiology can persist into adulthood, we tested the hypothesis that ethanol exposure in ferrets during a period equivalent to the last months of human gestation leads to persistent changes in astrocyte secretome in vitro. Animals were treated with ethanol (3.5g/kg) or saline between post-natal day (P)10-30. At P31, astrocyte cultures were made and cells were submitted to stable isotope labeling by amino acids (SILAC). 24h-conditioned media of cells obtained from ethanol- or saline-treated animals (ET-CM or SAL-CM) were collected and analyzed by quantitative mass spectrometry in tandem with liquid chromatography. Here we show that 65 out of 280 quantifiable proteins displayed significant differences comparing ET-CM to SAL-CM. Among the 59 proteins that were found to be reduced in ET-CM we observed components of the extracellular matrix such as Laminin subunits α2, α4, β1, β2 and γ1 and the proteoglycans Biglycan, Heparin Sulfate Proteoglycan 2 and Lumican. Proteins with trophic function such as Insulin-Like Growth Factor Binding Protein 4, Pigment Epithelium-Derived Factor and Clusterin as well as proteins involved on modulation of proteolysis such as TIMP-1 and PAI-1 were also reduced. In contrast, pro-synaptogeneic proteins like Thrombospondin-1, Hevin as well as the modulator of extracelular matrix expression, Angiotensinogen, were found increased in ET-CM. The analysis of interactome maps through Ingenuity Pathway Analysis demonstrated that the Amyloid beta A4 protein precursor (APP), which was found reduced in ET-CM, was previously shown to interact with ten other proteins that exhibited significant changes in the ET-CM. Taken together our results strongly suggest that early exposure to teratogens such as alcohol may lead to an enduring change in astrocyte secretome. PMID:26801685

  17. Viability of porcine nasal septal cartilage grafts following Nd:YAG (n=1.32μm) laser radiation

    NASA Astrophysics Data System (ADS)

    Chao, Kenneth K. H.; Wong, Brian J.; Kim, Hong K.; Milner, Thomas E.; Sung, Chung-Ho; Sobol, Emil N.; Nelson, J. Stuart

    2000-06-01

    Mechanically deformed morphologic cartilage grafts undergo a temperature dependent phase transformation during sustained laser irradiation that results in reshaping of the specimen. While thermal, optical, and mechanical properties of cartilage undergoing laser heating have been previously investigated, the viability of these irradiated grafts has yet to be examined closely until now. In this study, chondrocyte viability following laser irradiation was determined by measuring the incorporation of radiolabelled sulfate (Na 35SO4-2) into proteoglycan (PTG) macromolecules. Proteoglycans are highly sulfated and are the principal molecular constituents of cartilage matrix. Their synthesis directly reflects chondrocyte viability. By measuring the scintillation counts of 35SO4-2 uptake and normalizing the value by the total protein content of each specimen we can determine the level of PTG synthesis rates following laser reshaping. Regional baseline PTG synthesis rates as a function of location was determined by dividing each specimen into six regions. All regions except the most cephalic are demonstrated similar PTG synthesis rates. The most cephalic region exhibited a significantly greater PTG synthesis rates. In order to establish a positive control for this study, specimens were immersed in boiling saline water for approximately 40 minutes. The boiled specimens demonstrated a fivefold increase in normalized radioisotope uptake and suggest that the non-specific uptake of radioactive Na35SO4-2 is caused by structural alterations in the collagen matrix caused by extensive thermal exposure. To avoid this thermal artifact, another positive control was established using nitric oxide was to induce apoptosis of the chondrocytes, resulting in significantly lower PTG synthesis compared to untreated tissue. Cartilage specimens (25 X 10 X 2 mm) were irradiated with light emitted from an Nd:YAG laser (25 W/cm2, (lambda) equals 1.32 micrometer) while radiometric surface temperature, internal stress, and backscattered light were simultaneously recorded. Individual specimens underwent either one, two, or three sequential laser exposures with the duration of each exposure determined in real-time from observation of characteristic changes in integrated backscattered light intensity that correlate with thermal mediated stress relaxation. A five-minute time interval between each irradiation was given to allow the cartilage to return to thermal equilibrium. Average laser exposure for each irradiation sequence was recorded (5, 8.3, 12.2 sec). PTG synthesis decreased with increasing laser exposure, but was noted to remain above baseline levels for NO treated tissue. To further refine these results and minimize the effect of regional tissue variations, 7 mm diameter discs excised from the most cephalic portions and a middle region of the pig nasal septal cartilages were irradiated. A reduction of PTG synthesis rates was noted with each successive irradiation, suggesting that laser mediated cartilage reshaping acutely does not eliminate the population of viable chondrocytes. The degree of reduction in PTG synthesis is dependent upon the time-temperature dependent heating profile created during laser irradiation, and carefully monitored dosimetry is necessary to ensure chondrocyte viability.

  18. Effect of depletion of interstitial hyaluronan on hydraulic conductance in rabbit knee synovium

    PubMed Central

    Coleman, P J; Scott, D; Abiona, A; Ashhurst, D E; Mason, R M; Levick, J R

    1998-01-01

    The hydraulic resistance of the synovial lining to fluid outflow from a joint cavity () is important for the retention of intra-articular lubricant. The resistance has been attributed in part to extracellular glycosaminoglycans, including hyaluronan and chondroitin sulphates. Increased permeability in joints infused with testicular hyaluronidase, which digests both chondroitin sulphates and hyaluronan, supports this view. In this study the importance of interstitial hyaluronan per se was assessed using leech and Streptomyces hyaluronidases, which degrade only hyaluronan. Ringer solution was infused into the knee joint cavity of anaesthetized rabbits for 30 min, with or without hyaluronidase, after which intra-articular pressure (Pj) was raised and the relation between pressure and outflow determined. Treatment with Streptomyces, leech or testicular hyaluronidases increased the fluid escape rates by similar factors, namely 4- to 6-fold. After Streptomyces hyaluronidase treatment the slope d/dPj, which at low pressures represents synovial hydraulic conductance, increased from a control of 0.90 ± 0.20 μl min−1 cmH2O−1 (mean ± s.e.m., n = 6) to 4.52 ± 0.70 μl min−1 cmH2O−1. The slope d/dPj increased to a similar level after testicular hyaluronidase, namely to 4.14 ± 1.06 μl min−1 cmH2O−1 (control, 0.54 ± 0.24 μl min−1 cmH2O−1). Streptomyces and leech hyaluronidases were as effective as testicular hyaluronidase (no statistically significant differences) despite differences in substrate specificity. It was shown using histochemical and immunohistochemical techniques that hyaluronan was removed from the synovium by leech, Streptomyces and testicular hyaluronidases. The binding of antibodies 2-B-6 and 3-B-3 showed that the core proteins of the chondroitin sulphate proteoglycans remained intact after treatment with hyaluronidases, and the binding of 5-D-4 showed that keratan sulphate was unaffected. An azocasein digestion assay confirmed that the hyaluronidase preparations had no significant proteolytic activity. The effect of the hyaluronidases was four times greater than predicted from the low concentration of interstitial hyaluronan and its resistivity. Factors that might amplify the effect of hyaluronan depletion include the matrix-organizing role of hyaluronan, and/or non-uniformity of hyaluronan distribution. It is concluded that interstitial hyaluronan makes a major contribution to synovial hydraulic resistance, but the mechanisms are as yet poorly understood. PMID:9596792

  19. Small leucine-rich repeat proteoglycans associated with mature insoluble elastin serve as binding sites for galectins.

    PubMed

    Itoh, Aiko; Nonaka, Yasuhiro; Ogawa, Takashi; Nakamura, Takanori; Nishi, Nozomu

    2017-11-01

    We previously reported that galectin-9 (Gal-9), an immunomodulatory animal lectin, could bind to insoluble collagen preparations and exerted direct cytocidal effects on immune cells. In the present study, we found that mature insoluble elastin is capable of binding Gal-9 and other members of the human galectin family. Lectin blot analysis of a series of commercial water-soluble elastin preparations, PES-(A) ~ PES-(E), revealed that only PES-(E) contained substances recognized by Gal-9. Gal-9-interacting substances in PES-(E) were affinity-purified, digested with trypsin and then analyzed by reversed-phase HPLC. Peptide fragments derived from five members of the small leucine-rich repeat proteoglycan family, versican, lumican, osteoglycin/mimecan, prolargin, and fibromodulin, were identified by N-terminal amino acid sequence analysis. The results indicate that Gal-9 and possibly other galectins recognize glycans attached to small leucine-rich repeat proteoglycans associated with insoluble elastin and also indicate the possibility that mature insoluble elastin serves as an extracellular reservoir for galectins.

  20. Decorin is a Zn(2+) Metalloprotein

    NASA Technical Reports Server (NTRS)

    Yang, Vivian W.-C.; LaBrenz, Steven R.; Rosenberg, Lawrence C.; McQuillan, David; Hoeoek, Magnus

    1998-01-01

    Decorin is ubiquitously distributed in the extracellular matrix of mammals and a member of the proteoglycan family characterized by a core protein dominated by Leucine Rich Repeat motifs. We here demonstrate that decorin extracted from bovine tissues under denaturing conditions or produced in recombinant "native" form by cultured mammalian cells, has a high affinity for Zn(2+). Binding of Zn(2+) to decorin is demonstrated by Zn(2+) chelating chromatography and equilibrium dialyses. The Zn(2+) binding sites are localized to the N-terminal domain of the core protein that contains 4 Cys residues in the spacing reminiscent of a Zn finger. A recombinant 41 amino acid long peptide representing the N-terminal domain of decorin has full Zn(2+) binding activity and binds two Zn(2+) ions with an average K(D) of 3 x 10(exp -7) M. Biglycan, a proteoglycan that is structurally closely related to decorin contains a similar high affinity Zn(2+) binding segment, whereas the structurally more distantly related proteoglycans, epiphycan and osteoglycin, did not bind Zn(2+) with high affinity.

  1. Expression of small leucine-rich proteoglycans in rat anterior pituitary gland.

    PubMed

    Horiguchi, Kotaro; Syaidah, Rahimi; Fujiwara, Ken; Tsukada, Takehiro; Ramadhani, Dini; Jindatip, Depicha; Kikuchi, Motoshi; Yashiro, Takashi

    2013-01-01

    Proteoglycans are components of the extracellular matrix and comprise a specific core protein substituted with covalently linked glycosaminoglycan chains. Small leucine-rich proteoglycans (SLRPs) are a major family of proteoglycans and have key roles as potent effectors in cellular signaling pathways. Research during the last two decades has shown that SLRPs regulate biological functions in many tissues such as skin, tendon, kidney, liver, and heart. However, little is known of the expression of SLRPs, or the characteristics of the cells that produce them, in the anterior pituitary gland. Therefore, we have determined whether SLRPs are present in rat anterior pituitary gland. We have used real-time reverse transcription with the polymerase chain reaction to analyze the expression of SLRP genes and have identified the cells that produce SLRPs by using in situ hybridization with a digoxigenin-labeled cRNA probe. We have clearly detected the mRNA expression of SLRP genes, and cells expressing decorin, biglycan, fibromodulin, lumican, proline/arginine-rich end leucine-rich repeat protein (PRELP), and osteoglycin are located in the anterior pituitary gland. We have also investigated the possible double-staining of SLRP mRNA and pituitary hormones, S100 protein (a marker of folliculostellate cells), desmin (a marker of capillary pericytes), and isolectin B4 (a marker of endothelial cells). Decorin, biglycan, fibromodulin, lumican, PRELP, and osteoglycin mRNA have been identified in S100-protein-positive and desmin-positive cells. Thus, we conclude that folliculostellate cells and pericytes produce SLRPs in rat anterior pituitary gland.

  2. Changes in content and synthesis of collagen types and proteoglycans in osteoarthritis of the knee joint and comparison of quantitative analysis with Photoshop-based image analysis.

    PubMed

    Lahm, Andreas; Mrosek, Eike; Spank, Heiko; Erggelet, Christoph; Kasch, Richard; Esser, Jan; Merk, Harry

    2010-04-01

    The different cartilage layers vary in synthesis of proteoglycan and of the distinct types of collagen with the predominant collagen Type II with its associated collagens, e.g. types IX and XI, produced by normal chondrocytes. It was demonstrated that proteoglycan decreases in degenerative tissue and a switch from collagen type II to type I occurs. The aim of this study was to evaluate the correlation of real-time (RT)-PCR and Photoshop-based image analysis in detecting such lesions and find new aspects about their distribution. We performed immunohistochemistry and histology with cartilage tissue samples from 20 patients suffering from osteoarthritis compared with 20 healthy biopsies. Furthermore, we quantified our results on the gene expression of collagen type I and II and aggrecan with the help of real-time (RT)-PCR. Proteoglycan content was measured colorimetrically. Using Adobe Photoshop the digitized images of histology and immunohistochemistry stains of collagen type I and II were stored on an external data storage device. The area occupied by any specific colour range can be specified and compared in a relative manner directly from the histogram using the "magic wand tool" in the select similar menu. In the image grow menu gray levels or luminosity (colour) of all pixels within the selected area, including mean, median and standard deviation, etc. are depicted. Statistical Analysis was performed using the t test. With the help of immunohistochemistry, RT-PCR and quantitative RT- PCR we found that not only collagen type II, but also collagen type I is synthesized by the cells of the diseased cartilage tissue, shown by increasing amounts of collagen type I mRNA especially in the later stages of osteoarthritis. A decrease of collagen type II is visible especially in the upper fibrillated area of the advanced osteoarthritic samples, which leads to an overall decrease. Analysis of proteoglycan showed a loss of the overall content and a quite uniform staining in the different zones compared to the healthy cartilage with a classical zonal formation. Correlation analysis of the proteoglycan Photoshop measurements with the RT-PCR using Spearman correlation analysis revealed strong correlation for Safranin O and collagen type I, medium for collagen type II and glycoprotein but weak correlation between PCR aggrecan results. Photoshop-based image analysis might become a valuable supplement for well known histopathological grading systems of lesioned articular cartilage.

  3. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wall, Jonathan; Martin, Emily B.; Richey, Tina

    Amyloid is a complex pathologic matrix comprised principally of para-crystalline protein fibrils and heparan sulfate proteoglycans. Systemic amyloidoses are rare (~3500 new cases per year in the US); thus, routine diagnosis is often challenging, and effective treatment options are limited, resulting in high morbidity and mortality rates. Glycosaminoglycans contribute inextricably to the formation of amyloid fibrils and foster the deposition of amyloid in tissues. Those present in amyloid deposits are biochemically and electrochemically distinct from glycosaminoglycans found in the plasma membrane and extracellular matrices of healthy tissues due to the presence of a high degree of heparin-like hypersulfation. We havemore » exploited this unique property and evaluated heparin-reactive peptides, such as p5+14. Herein we show efficacious detection of murine systemic amyloid in vivo by using molecular imaging, and the specific targeting of the peptide to major forms of human amyloid in tissue sections. Furthermore, we have demonstrated that the peptide also binds synthetic amyloid fibrils that lack glycosaminoglycans implying that the dense anionic motif present on heparin is mimicked by the amyloid protein fibril itself. These biochemical and functional data support the translation of radiolabeled peptide p5+14 for the clinical imaging of amyloid in patients; thus, providing a novel technique for prognostication, patient stratification, and monitoring response to therapy.« less

  4. Reduction of Syndecan Transcript Levels in the Insulin-Producing Cells Affects Glucose Homeostasis in Adult Drosophila melanogaster.

    PubMed

    Warren, Jonathan L; Hoxha, Eneida; Jumbo-Lucioni, Patricia; De Luca, Maria

    2017-11-01

    Signaling by direct cell-matrix interactions has been shown to impact the transcription, secretion, and storage of insulin in mammalian β cells. However, more research is still needed in this area. Syndecans are transmembrane heparan sulfate proteoglycans that function independently and in synergy with integrin-mediated signaling to mediate cell adhesion to the extracellular matrix. In this study, we used the model organism Drosophila melanogaster to determine whether knockdown of the Syndecan (Sdc) gene expression specifically in the insulin-producing cells (IPCs) might affect insulin-like peptide (ILP) production and secretion. IPCs of adult flies produce three ILPs (ILP2, ILP3, and ILP5), which have significant homology to mammalian insulin. We report that flies with reduced Sdc expression in the IPCs did not show any difference in the expression of ilp genes compared to controls. However, they had significantly reduced levels of the circulating ILP2 protein, higher circulating carbohydrates, and were less glucose tolerant than control flies. Finally, we found that IPCs-specific Sdc knockdown led to reduced levels of head Glucose transporter1 gene expression, extracellular signal-regulated kinase phosphorylation, and reactive oxygen species. Taken together, our findings suggest a cell autonomous role for Sdc in insulin release in D. melanogaster.

  5. Motoneurons secrete angiogenin to induce RNA cleavage in astroglia.

    PubMed

    Skorupa, Alexandra; King, Matthew A; Aparicio, Isabela M; Dussmann, Heiko; Coughlan, Karen; Breen, Bridget; Kieran, Dairin; Concannon, Caoimhin G; Marin, Philippe; Prehn, Jochen H M

    2012-04-11

    Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disorder affecting motoneurons. Mutations in angiogenin, encoding a member of the pancreatic RNase A superfamily, segregate with ALS. We previously demonstrated that angiogenin administration shows promise as a neuroprotective therapeutic in studies using transgenic ALS mice and primary motoneuron cultures. Its mechanism of action and target cells in the spinal cord, however, are largely unknown. Using mixed motoneuron cultures, motoneuron-like NSC34 cells, and primary astroglia cultures as model systems, we here demonstrate that angiogenin is a neuronally secreted factor that is endocytosed by astroglia and mediates neuroprotection in paracrine. We show that wild-type angiogenin acts unidirectionally to induce RNA cleavage in astroglia, while the ALS-associated K40I mutant is also secreted and endocytosed, but fails to induce RNA cleavage. Angiogenin uptake into astroglia requires heparan sulfate proteoglycans, and engages clathrin-mediated endocytosis. We show that this uptake mechanism exists for mouse and human angiogenin, and delivers a functional RNase output. Moreover, we identify syndecan 4 as the angiogenin receptor mediating the selective uptake of angiogenin into astroglia. Our data provide new insights into the paracrine activities of angiogenin in the nervous system, and further highlight the critical role of non-neuronal cells in the pathogenesis of ALS.

  6. Perlecan expression influences the keratin 15‐positive cell population fate in the epidermis of aging skin

    PubMed Central

    Dos Santos, Morgan; Michopoulou, Anna; André‐Frei, Valérie; Boulesteix, Sophie; Guicher, Christine; Dayan, Guila; Whitelock, John; Damour, Odile; Rousselle, Patricia

    2016-01-01

    The epidermis is continuously renewed by stem cell proliferation and differentiation. Basal keratinocytes append the dermal‐epidermal junction, a cell surface‐associated, extracellular matrix that provides structural support and influences their behaviour. It consists of laminins, type IV collagen, nidogens, and perlecan, which are necessary for tissue organization and structural integrity. Perlecan is a heparan sulfate proteoglycan known to be involved in keratinocyte survival and differentiation. Aging affects the dermal epidermal junction resulting in decreased contact with keratinocytes, thus impacting epidermal renewal and homeostasis. We found that perlecan expression decreased during chronological skin aging. Our in vitro studies revealed reduced perlecan transcript levels in aged keratinocytes. The production of in vitro skin models revealed that aged keratinocytes formed a thin and poorly organized epidermis. Supplementing these models with purified perlecan reversed the phenomenon allowing restoration of a well‐differentiated multi‐layered epithelium. Perlecan down‐regulation in cultured keratinocytes caused depletion of the cell population that expressed keratin 15. This phenomenon depended on the perlecan heparan sulphate moieties, which suggested the involvement of a growth factor. Finally, we found defects in keratin 15 expression in the epidermis of aging skin. This study highlighted a new role for perlecan in maintaining the self‐renewal capacity of basal keratinocytes. PMID:26996820

  7. Shortwave-infrared Raman spectroscopic classification of water fractions in articular cartilage ex vivo

    NASA Astrophysics Data System (ADS)

    Unal, Mustafa; Akkus, Ozan

    2018-01-01

    Water loss is an early onset indicator of osteoarthritis. Although Raman spectroscopy (RS) holds the potential for measurement of cartilage hydration, the knowledge of Raman OH-stretch bands of biological tissue is very limited. We assesed here the sensitivity of RS to identify and classify water types in the cartilage. Raman spectrum measurements over the high wavenumber range were employed to identify different water fractions in articular cartilage. Raman spectra were collected from wet and sequentially dehydrated cartilage along with pure collagen type II and chondroitin sulfate standards. OH-stretch band of cartilage is dominated by mobile water, up to 95% of total intensities. We identified six peaks in cartilage spectrum using second-derivative analysis: peaks at 3200 and 3650 cm-1 are associated with organic matrix (both collagen and proteglycan) and matrix-bound water molecules. Peaks at 3250, 3453, and 3630 cm-1 are associated with collagen and collagen-related water molecules, whereas the peak at 3520 cm-1 is associated with proteoglycan (PG) and PG-related water molecules. The current work is the first thorough analysis of the Raman OH-stretch band of the cartilage and with the knowledge generated by this study, it may now be possible to study on cartilage hydration by RS.

  8. Tumor Cell Plasticity in Uveal Melanoma

    PubMed Central

    Folberg, Robert; Arbieva, Zarema; Moses, Jonas; Hayee, Amin; Sandal, Tone; Kadkol, ShriHari; Lin, Amy Y.; Valyi-Nagy, Klara; Setty, Suman; Leach, Lu; Chévez-Barrios, Patricia; Larsen, Peter; Majumdar, Dibyen; Pe’er, Jacob; Maniotis, Andrew J.

    2006-01-01

    The histological detection of laminin-rich vasculogenic mimicry patterns in human primary uveal melanomas is associated with death from metastases. We therefore hypothesized that highly invasive uveal melanoma cells forming vasculogenic mimicry patterns after exposure to a laminin-rich three-dimensional microenvironment would differentially express genes associated with invasive and metastatic behavior. However, we discovered that genes associated with differentiation (GDF15 and ATF3) and suppression of proliferation (CDKNa1/p21) were up-regulated in highly invasive uveal melanoma cells forming vasculogenic mimicry patterns, and genes associated with promotion of invasive and metastatic behavior such as CD44, CCNE2 (cyclin E2), THBS1 (thrombospondin 1), and CSPG2 (chondroitin sulfate proteoglycan; versican) were down-regulated. After forming vasculogenic mimicry patterns, uveal melanoma cells invaded only short distances, failed to replicate, and changed morphologically from the invasive epithelioid to the indolent spindle A phenotype. In human tissue samples, uveal melanoma cells within vasculogenic mimicry patterns assumed the spindle A morphology, and the expression of Ki67 was significantly reduced in adjacent melanoma cells. Thus, the generation of vasculogenic mimicry patterns is accompanied by dampening of the invasive and metastatic uveal melanoma genotype and phenotype and underscores the plasticity of these cells in response to cues from the microenvironment. PMID:17003493

  9. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation.

    PubMed

    Gaviglio, Angela L; Knelson, Erik H; Blobe, Gerard C

    2017-05-01

    High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor-like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.-Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. © FASEB.

  10. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation

    PubMed Central

    Gaviglio, Angela L.; Knelson, Erik H.; Blobe, Gerard C.

    2017-01-01

    High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor–like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.—Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. PMID:28174207

  11. Interaction of Human Tumor Viruses with Host Cell Surface Receptors and Cell Entry

    PubMed Central

    Schäfer, Georgia; Blumenthal, Melissa J.; Katz, Arieh A.

    2015-01-01

    Currently, seven viruses, namely Epstein-Barr virus (EBV), Kaposi’s sarcoma-associated herpes virus (KSHV), high-risk human papillomaviruses (HPVs), Merkel cell polyomavirus (MCPyV), hepatitis B virus (HBV), hepatitis C virus (HCV) and human T cell lymphotropic virus type 1 (HTLV-1), have been described to be consistently associated with different types of human cancer. These oncogenic viruses belong to distinct viral families, display diverse cell tropism and cause different malignancies. A key to their pathogenicity is attachment to the host cell and entry in order to replicate and complete their life cycle. Interaction with the host cell during viral entry is characterized by a sequence of events, involving viral envelope and/or capsid molecules as well as cellular entry factors that are critical in target cell recognition, thereby determining cell tropism. Most oncogenic viruses initially attach to cell surface heparan sulfate proteoglycans, followed by conformational change and transfer of the viral particle to secondary high-affinity cell- and virus-specific receptors. This review summarizes the current knowledge of the host cell surface factors and molecular mechanisms underlying oncogenic virus binding and uptake by their cognate host cell(s) with the aim to provide a concise overview of potential target molecules for prevention and/or treatment of oncogenic virus infection. PMID:26008702

  12. Raman microspectrometry of laser-reshaped rabbit auricular cartilage: preliminary study on laser-induced cartilage mineralization

    NASA Astrophysics Data System (ADS)

    Heger, Michal; Mordon, Serge R.; Leroy, Gérard; Fleurisse, Laurence; Creusy, Collette

    2006-03-01

    Laser-assisted cartilage reshaping (LACR) is a relatively novel technique designed to noninvasively and permanently restructure cartilaginous tissue. It is believed that heat-induced stress relaxation, in which a temperature-mediated disruption of H2O binding is associated with conformational alterations in the proteoglycan and collagen-rich matrix, constitutes the underlying mechanism of LACR. Several reports have suggested that laser-mediated cartilage mineralization may contribute to the permanent shape change of laser-reshaped cartilage. In an effort to validate these results in the context of Er:glass LACR, we performed a preliminary Raman microspectrometric study to characterize the crystal deposits in laser-irradiated chondrocytes and extracellular matrix. For the first time, we identified intracellular calcium sulfate deposits and extracellular calcium phosphate (apatite) crystals in laser-reshaped rabbit auricular cartilage. Calcium carbonate deposits are localized in both irradiated and nonirradiated samples, suggesting that this mineral plays no role in conformational retention. In our discussion, we elaborate on the possible molecular and cellular mechanisms responsible for intra- and extracellular crystallization, and propose a novel hypothesis on the formation of apatite, inasmuch as the biological function of this mineral (providing structure and rigidity in bones and dental enamel) may be extrapolated to the permanent shape change of laser-irradiated cartilage.

  13. Low Piconewton Towing of CNS Axons against Diffusing and Surface-Bound Repellents Requires the Inhibition of Motor Protein-Associated Pathways

    NASA Astrophysics Data System (ADS)

    Kilinc, Devrim; Blasiak, Agata; O'Mahony, James J.; Lee, Gil U.

    2014-11-01

    Growth cones, dynamic structures at axon tips, integrate chemical and physical stimuli and translate them into coordinated axon behaviour, e.g., elongation or turning. External force application to growth cones directs and enhances axon elongation in vitro; however, direct mechanical stimulation is rarely combined with chemotactic stimulation. We describe a microfluidic device that exposes isolated cortical axons to gradients of diffusing and substrate-bound molecules, and permits the simultaneous application of piconewton (pN) forces to multiple individual growth cones via magnetic tweezers. Axons treated with Y-27632, a RhoA kinase inhibitor, were successfully towed against Semaphorin 3A gradients, which repel untreated axons, with less than 12 pN acting on a small number of neural cell adhesion molecules. Treatment with Y-27632 or monastrol, a kinesin-5 inhibitor, promoted axon towing on substrates coated with chondroitin sulfate proteoglycans, potent axon repellents. Thus, modulating key molecular pathways that regulate contractile stress generation in axons counteracts the effects of repellent molecules and promotes tension-induced growth. The demonstration of parallel towing of axons towards inhibitory environments with minute forces suggests that mechanochemical stimulation may be a promising therapeutic approach for the repair of the damaged central nervous system, where regenerating axons face repellent factors over-expressed in the glial scar.

  14. Chondrodysplasia with multiple dislocations: comprehensive study of a series of 30 cases.

    PubMed

    Ranza, E; Huber, C; Levin, N; Baujat, G; Bole-Feysot, C; Nitschke, P; Masson, C; Alanay, Y; Al-Gazali, L; Bitoun, P; Boute, O; Campeau, P; Coubes, C; McEntagart, M; Elcioglu, N; Faivre, L; Gezdirici, A; Johnson, D; Mihci, E; Nur, B G; Perrin, L; Quelin, C; Terhal, P; Tuysuz, B; Cormier-Daire, V

    2017-06-01

    The group of chondrodysplasia with multiple dislocations includes several entities, characterized by short stature, dislocation of large joints, hand and/or vertebral anomalies. Other features, such as epiphyseal or metaphyseal changes, cleft palate, intellectual disability are also often part of the phenotype. In addition, several conditions with overlapping features are related to this group and broaden the spectrum. The majority of these disorders have been linked to pathogenic variants in genes encoding proteins implicated in the synthesis or sulfation of proteoglycans (PG). In a series of 30 patients with multiple dislocations, we have performed exome sequencing and subsequent targeted analysis of 15 genes, implicated in chondrodysplasia with multiple dislocations, and related conditions. We have identified causative pathogenic variants in 60% of patients (18/30); when a clinical diagnosis was suspected, this was molecularly confirmed in 53% of cases. Forty percent of patients remain without molecular etiology. Pathogenic variants in genes implicated in PG synthesis are of major importance in chondrodysplasia with multiple dislocations and related conditions. The combination of hand features, growth failure severity, radiological aspects of long bones and of vertebrae allowed discrimination among the different conditions. We propose key diagnostic clues to the clinician. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. {sup 1}H NMR spectroscopic studies establish that heparanase is a retaining glycosidase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wilson, Jennifer C., E-mail: jennifer.wilson@griffith.edu.au; Laloo, Andrew Elohim; Singh, Sanjesh

    2014-01-03

    Highlights: •{sup 1}H and {sup 13}C NMR chemical shifts of fondaparinux were fully assigned by 1D and 2D NMR techniques. •Hydrolysis of fondaparinux by heparanase was monitored by {sup 1}H NMR spectroscopy. •Heparanase is established to be a retaining glycosidase. -- Abstract: Heparanase is an endo-β-glucuronidase that cleaves heparan sulfate side chains of proteoglycans in basement membranes and the extracellular matrix (ECM). Heparanase is implicated in several diverse pathological processes associated with ECM degradation such as metastasis, inflammation and angiogenesis and is thus an important target for anti-cancer and anti-inflammatory drug discovery. Heparanase has been classed as belonging to themore » clan A glycoside hydrolase family 79 based on sequence analysis, secondary structure predictions and mutagenic analysis, and thus it has been inferred that it is a retaining glycosidase. However, there has been no direct experimental evidence to support this conclusion. Herein we describe {sup 1}H NMR spectroscopic studies of the hydrolysis of the pentasaccharide substrate fondaparinux by heparanase, and provide conclusive evidence that heparanase hydrolyses its substrate with retention of configuration and is thus established as a retaining glycosidase. Knowledge of the mechanism of hydrolysis may have implications for future design of inhibitors for this important drug target.« less

  16. Distribution of type VI collagen in association with osteoblast lineages in the groove of Ranvier during rat postnatal development.

    PubMed

    Kohara, Yukihiro; Soeta, Satoshi; Izu, Yayoi; Arai, Kiyotaka; Amasaki, Hajime

    2016-11-01

    In the groove of Ranvier (GOR), osteoblast lineages form bone bark, which develops into endosteal cortical bone. This ossification process is thought to be regulated by the microenvironment in the GOR. Type VI collagen (Col VI), an extracellular matrix (ECM) protein found in the periosteum/perichondrium, mediates osteoblast differentiation via the cell-surface receptor neural/glial antigen 2 (NG2) chondroitin sulfate proteoglycan. In order to clarify the function of Col VI during osteoblast differentiation in the GOR, in the present study, we examined the distribution of Col VI and osteoblast lineages expressing NG2 in the rat tibia proximal end during postnatal growing periods by immunohistochemistry. Our data revealed that Col VI accumulated in the ECM of the GOR middle layer and that Col VI accumulation was reduced and disappeared in the inner and middle lower regions. Runt-related transcription factor 2-immunoreactive pre-osteoblasts expressed NG2 in Col VI-immunopositive areas. However, Osterix-immunoreactive mature osteoblasts were only found in the Col VI-immunonegative area. These findings indicate that Col VI provided a characteristic microenvironment in the GOR and that NG2-Col VI interactions may regulate the differentiation of osteoblast lineages prior to terminal maturation. Copyright © 2016 Elsevier GmbH. All rights reserved.

  17. Characterization of the fibrillar layer at the epithelial-mesenchymal junction in tooth germs.

    PubMed

    Sawada, T; Inoue, S

    1994-12-01

    A characteristic layer containing numerous fibrils is associated with the basement membrane of the inner enamel epithelium during the early stages of odontogenesis. However, its nature is not well understood. In this study, the layer was examined with high-resolution electron microscopy and immuno-histochemical staining. Tooth germs of monkeys (Macaca fuscata) were studied and each fibril in the layer was found to be a tubular structure, 8-9 nm in width, resembling a "basotubule", the tubular structure previously observed in various basement membranes. The space between the fibrils was filled with a network formed by irregular anastomosing strands with an average thickness of 4 nm; these strands resembled the "cords" forming the network in the lamina densa of basement membranes. After immunoperoxidase staining, fine threads immunoreactive for laminin staining were seen winding along the strands of the network, and 1.5-nm wide filaments, immunoreactive for type IV collagen, took the form of a network arrangement. The 5-nm-wide ribbon-like structures associated with the strands were identified as heparan sulfate proteoglycan by immunostaining. These results are similar to those obtained for the cord network of the lamina densa. The "fibrillar layer" therefore represents a highly specialized lamina fibroreticularis of the basement membrane of the inner enamel epithelium, and rich in basotubules.

  18. Role of heparanase on hepatic uptake of intestinal derived lipoprotein and fatty streak formation in mice.

    PubMed

    Planer, David; Metzger, Shulamit; Zcharia, Eyal; Wexler, Isaiah D; Vlodavsky, Israel; Chajek-Shaul, Tova

    2011-04-04

    Heparanase modulates the level of heparan sulfate proteoglycans (HSPGs) which have an important role in multiple cellular processes. Recent studies indicate that HSPGs have an important function in hepatic lipoprotein handling and processes involving removal of lipoprotein particles. To determine the effects of decreased HSPGs chain length on lipoprotein metabolism and atherosclerosis, transgenic mice over-expressing the human heparanase gene were studied. Hepatic lipid uptake in hpa-Tg mice were evaluated by giving transgenic mice oral fat loads and labeled retinol. Sections of aorta from mice over-expressing heparanase (hpa-Tg) and controls (C57/BL6) fed an atherogenic diet were examined for evidence of atherosclerosis. Heparanase over-expression results in reduced hepatic clearance of postprandial lipoproteins and higher levels of fasting and postprandial serum triglycerides. Heparanase over-expression also induces formation of fatty streaks in the aorta. The mean lesion cross-sectional area in heparanase over-expressing mice was almost 6 times higher when compared to control mice (23,984 µm(2)±5,922 vs. 4,189 µm(2)±1,130, p<0.001). Over-expression of heparanase demonstrates the importance of HSPGs for the uptake of intestinal derived lipoproteins and its role in the formation of fatty streaks.

  19. Role of Heparanase on Hepatic Uptake of Intestinal Derived Lipoprotein and Fatty Streak Formation in Mice

    PubMed Central

    Planer, David; Metzger, Shulamit; Zcharia, Eyal; Wexler, Isaiah D.; Vlodavsky, Israel; Chajek-Shaul, Tova

    2011-01-01

    Background Heparanase modulates the level of heparan sulfate proteoglycans (HSPGs) which have an important role in multiple cellular processes. Recent studies indicate that HSPGs have an important function in hepatic lipoprotein handling and processes involving removal of lipoprotein particles. Principal Findings To determine the effects of decreased HSPGs chain length on lipoprotein metabolism and atherosclerosis, transgenic mice over-expressing the human heparanase gene were studied. Hepatic lipid uptake in hpa-Tg mice were evaluated by giving transgenic mice oral fat loads and labeled retinol. Sections of aorta from mice over-expressing heparanase (hpa-Tg) and controls (C57/BL6) fed an atherogenic diet were examined for evidence of atherosclerosis. Heparanase over-expression results in reduced hepatic clearance of postprandial lipoproteins and higher levels of fasting and postprandial serum triglycerides. Heparanase over-expression also induces formation of fatty streaks in the aorta. The mean lesion cross-sectional area in heparanase over-expressing mice was almost 6 times higher when compared to control mice (23,984 µm2±5,922 vs. 4,189 µm2±1,130, p<0.001). Conclusions Over-expression of heparanase demonstrates the importance of HSPGs for the uptake of intestinal derived lipoproteins and its role in the formation of fatty streaks. PMID:21483695

  20. Correlation of Versican Expression, Accumulation, and Degradation during Embryonic Development by Quantitative Immunohistochemistry

    PubMed Central

    Snyder, Jessica M.; Washington, Ida M.; Birkland, Timothy; Chang, Mary Y.; Frevert, Charles W.

    2015-01-01

    Versican, a chondroitin sulfate proteoglycan, is important in embryonic development, and disruption of the versican gene is embryonically lethal in the mouse. Although several studies show that versican is increased in various organs during development, a focused quantitative study on versican expression and distribution during lung and central nervous system development in the mouse has not previously been performed. We tracked changes in versican (Vcan) gene expression and in the accumulation and degradation of versican. Vcan expression and quantitative immunohistochemistry performed from embryonic day (E) 11.5 to E15.5 showed peak Vcan expression at E13.5 in the lungs and brain. Quantitative mRNA analysis and versican immunohistochemistry showed differences in the expression of the versican isoforms in the embryonic lung and head. The expression of Vcan mRNA and accumulation of versican in tissues was complementary. Immunohistochemistry demonstrated co-localization of versican accumulation and degradation, suggesting distinct roles of versican deposition and degradation in embryogenesis. Very little versican mRNA or protein was found in the lungs of 12- to 16-week-old mice but versican accumulation was significantly increased in mice with Pseudomonas aeruginosa lung infection. These data suggest that versican plays an important role in fundamental, overlapping cellular processes in lung development and infection. PMID:26385570

  1. Reelin Promotes Neuronal Orientation and Dendritogenesis during Preplate Splitting

    PubMed Central

    Nichols, Anna J.

    2010-01-01

    The secreted ligand Reelin is thought to regulate the translocation and positioning of prospective layer 6 (L6) neurons into the preplate, a plexus of neurons overlying the ventricular zone. We examined wild type and Reelin-deficient cortices and found that L6 neurons were equivalently positioned beneath the pia during the period of preplate splitting and initial cortical plate (CP) formation. The absence of detectable L6 ectopia in “reeler” cortices at this developmental time point indicates that Reelin-signaling might not regulate L6 neuron migration or gross positioning during preplate splitting. To explore the acute response of L6 neurons to Reelin, subpial injections of Reelin were made into Reelin-deficient explants. Reelin injection caused L6 neurons to orient their nuclei and polarize their Golgi toward the pia while initiating exuberant dendritic (MAP2+) outgrowth within 4 h. This rapid Reelin-dependent neuronal orientation and alignment created CP-like histology without any significant change in the mean position of the population of L6 neurons. Conversely, subplate cells and chondroitin sulfate proteoglycan immunoreactivity were found at significantly deeper positions from the pial surface after injection, suggesting that Reelin partially rescues preplate splitting within 4 h. Thus, Reelin has a direct role in promoting rapid morphological differentation and orientation of L6 neurons during preplate splitting. PMID:20064940

  2. The Extract of Roots of Sophora flavescens Enhances the Recovery of Motor Function by Axonal Growth in Mice with a Spinal Cord Injury

    PubMed Central

    Tanabe, Norio; Kuboyama, Tomoharu; Kazuma, Kohei; Konno, Katsuhiro; Tohda, Chihiro

    2016-01-01

    Although axonal extension to reconstruct spinal tracts should be effective for restoring function after spinal cord injury (SCI), chondroitin sulfate proteoglycan (CSPG) levels increase at spinal cord lesion sites, and inhibit axonal regrowth. In this study, we found that the water extract of roots of Sophora flavescens extended the axons of mouse cortical neurons, even on a CSPG-coated surface. Consecutive oral administrations of S. flavescens extract to SCI mice for 31 days increased the density of 5-HT-positive axons at the lesion site and improved the motor function. Further, the active constituents in the S. flavescens extract were identified. The water and alkaloid fractions of the S. flavescens extract each exhibited axonal extension activity in vitro. LC/MS analysis revealed that these fractions mainly contain matrine and/or oxymatrine, which are well-known major compounds in S. flavescens. Matrine and oxymatrine promoted axonal extension on the CSPG-coated surface. This study is the first to demonstrate that S. flavescens extract, matrine, and oxymatrine enhance axonal growth in vitro, even on a CSPG-coated surface, and that S. flavescens extract improves motor function and increases axonal density in SCI mice. PMID:26834638

  3. Bovine lactoferricin induces TIMP-3 via the ERK1/2-Sp1 axis in human articular chondrocytes.

    PubMed

    Yan, Dongyao; Chen, Di; Hawse, John R; van Wijnen, Andre J; Im, Hee-Jeong

    2013-03-15

    Bovine lactoferricin (LfcinB) is a heparan sulfate-binding peptide with multiple bioactivities. In human articular cartilage, LfcinB antagonizes interleukin-1 β (IL-1β) and fibroblast growth factor 2 (FGF-2) in proteoglycan metabolism, catabolic protease expression, and induction of pro-inflammatory mediators. LfcinB specifically activates ERK1/2, p38 and Akt, but whether these signaling pathways control the expression of LfcinB target genes remained unknown. In this report, we characterized a novel aspect of LfcinB-mediated genetic response in human articular chondrocytes, tissue inhibitor of metalloproteinase 3 (TIMP-3) induction. Inhibition of individual signaling pathways revealed that ERK1/2 functions as the major pathway in TIMP-3 expression, whereas Akt plays a minor role. Further investigation identified Sp1 as a critical transcriptional activator in TIMP-3 regulation, and Sp1 activity is modulated by ERK1/2, not Akt. Comparative quantification indicates that significant downregulation of TIMP-3 occurs in OA chondrocytes, suggesting a beneficial role of LfcinB in OA pathogenesis. Our results collectively provide new insights into the mechanism of action of LfcinB, and support the candidacy of LfcinB as a chondroprotective agent. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Effects of concanavalin A on chondrocyte hypertrophy and matrix calcification.

    PubMed

    Yan, W; Pan, H; Ishida, H; Nakashima, K; Suzuki, F; Nishimura, M; Jikko, A; Oda, R; Kato, Y

    1997-03-21

    Resting chondrocytes do not usually undergo differentiation to the hypertrophic stage and calcification. However, incubating these cells with concanavalin A resulted in 10-100-fold increases in alkaline phosphatase activity, binding of 1,25(OH)2-vitamin D3, type X collagen synthesis, 45Ca incorporation into insoluble material, and calcium content. On the other hand, other lectins tested (including wheat germ agglutinin, lentil lectin, pea lectin, phytohemagglutinin-L, and phytohemagglutinin-E) marginally affected alkaline phosphatase activity, although they activate lymphocytes. Methylmannoside reversed the effect of concanavalin A on alkaline phosphatase within 48 h. Concanavalin A did not increase alkaline phosphatase activity in articular chondrocyte cultures. In resting chondrocyte cultures, succinyl concanavalin A was as potent as concanavalin A in increasing alkaline phosphatase activity, the incorporation of [35S]sulfate, D-[3H]glucosamine, and [3H]serine into proteoglycans, and the incorporation of [3H]serine into protein, although concanavalin A, but not succinyl concanavalin A, induced a rapid change in the shape of the cells from flat to spherical. These findings suggest that concanavalin A induces a switch from the resting, to the growth-plate stage, and that this action of concanavalin A is not secondary to changes in the cytoskeleton. Chondrocytes exposed to concanavalin A may be useful as a novel model of endochondral bone formation.

  5. Redistribution of insoluble interphotoreceptor matrix components during photoreceptor differentiation in the mouse retina.

    PubMed

    Mieziewska, K; Szél, A; Van Veen, T; Aguirre, G D; Philp, N

    1994-07-01

    The development of the nervous system is largely influenced by the extracellular matrix (ECM). In the neural retina, the photoreceptors are surrounded by a unique ECM, the interphotoreceptor matrix (IPM). The IPM plays a central and possibly crucial role in the development, maintenance and specific function of the photoreceptors. Therefore, the characterization of IPM components is necessary to understand the mechanisms regulating photoreceptor differentiation. The IPM in the mouse retina was examined during photoreceptor morphogenesis with the monoclonal antibody (MAb) F22, which recognizes a 250 kDa component of the interphotoreceptor matrix. The binding pattern of MAb F22 revealed a striking redistribution in the expression of the 250 kDa F22 antigen in late stage of postnatal photoreceptor differentiation in the mouse retina. The F22 staining was detectable in the IPM around the inner segments on the third postnatal day (P3). The MAb F22 initially labeled the region around inner segments, but as the outer segments elongated, the F22 distribution became concentrated to the matrix around the rod and cone outer segments until P16-17. At P17, the F22 label around rods began to disappear, while the label around cones became more defined. The shift in label distribution was largely completed by P20. Residual rod-associated label disappeared within a few days. In the adult animal, the F22 antibody labeled the cone-associated matrix only, and this labeling pattern remained stationary. The change in the distribution of MAb F22 demonstrated by immunolabeling was not accompanied by changes in the size of the molecule; F22 antigen isolated from the IPM of P13-15, and from adult IPM migrated with the same molecular weight on SDS gels. The distribution of MAb F22 was compared to that of chondroitin sulfate proteoglycans which are abundant in the IPM. The labeling patterns of MAbs CS-56, C6-S and C4-S were distinct from that of MAb F22. A general decrease of the label intensity was seen with two chondroitin sulfate MAbs (CS-56 and C4-S) between 16 days and 4 months, but a total loss of rod-associated label was not observed. All three chondroitin sulfate MAbs labeled the retina at embryonic day (E) 11.5-13.5, a time of outgrowth of ganglion cell axons, but the F22 antigen was not detected in the retina at this stage of development. The results demonstrate that the F22 and the chondroitin sulfate antibodies are recognizing different molecules that have distinct roles in retinal morphogenesis.(ABSTRACT TRUNCATED AT 400 WORDS)

  6. Acetylcholine, ATP, and proteoglycan are common to synaptic vesicles isolated from the electric organs of electric eel and electric catfish as well as from rat diaphragm.

    PubMed

    Volknandt, W; Zimmermann, H

    1986-11-01

    Cholinergic synaptic vesicles were isolated from the electric organs of the electric eel (Electrophorus electricus) and the electric catfish (Malapterurus electricus) as well as from the diaphragm of the rat by density gradient centrifugation followed by column chromatography on Sephacryl-1000. This was verified by both biochemical and electron microscopic criteria. Differences in size between synaptic vesicles from the various tissue sources were reflected by their elution pattern from the Sephacryl column. Specific activities of acetylcholine (ACh; in nmol/mg of protein) of chromatography-purified vesicle fractions were 36 (electric eel), 2 (electric catfish), and 1 (rat diaphragm). Synaptic vesicles from all three sources contained ATP in addition to ACh (molar ratios of ACh/ATP, 9-12) as well as binding activity for an antibody raised against Torpedo cholinergic synaptic vesicle proteoglycan. Synaptic vesicles from rat diaphragm contained binding activity for the monoclonal antibody asv 48 raised against a rat brain 65-kilodalton synaptic vesicle protein. Antibody asv 48 binding was absent from electric eel and electric catfish synaptic vesicles. These antibody binding results, which were obtained by a dot blot assay on isolated vesicles, directly correspond to the immunocytochemical results demonstrating fluorescein isothiocyanate staining in the respective nerve terminals. Our results imply that ACh, ATP, and proteoglycan are common molecular constituents of motor nerve terminal-derived synaptic vesicles from Torpedo to rat. In addition to ACh, both ATP and proteoglycan may play a specific role in the process of cholinergic signal transmission.

  7. Cartilage proteoglycans inhibit fibronectin-mediated adhesion

    NASA Astrophysics Data System (ADS)

    Rich, A. M.; Pearlstein, E.; Weissmann, G.; Hoffstein, S. T.

    1981-09-01

    Normal tissues and organs show, on histological examination, a pattern of cellular and acellular zones that is characteristic and unique for each organ or tissue. This pattern is maintained in health but is sometimes destroyed by disease. For example, in mobile joints, the articular surfaces consist of relatively acellular hyaline cartilage, and the joint space is enclosed by a capsule of loose connective tissue with a lining of fibroblasts and macrophages. In the normal joint these cells are confined to the synovial lining and the articular surface remains acellular. In in vitro culture, macrophages and their precursor monocytes are very adhesive, and fibroblasts can migrate and overgrow surfaces such as collagen or plastic used for tissue culture. The fibroblasts adhere to collagen by means of fibronectin, which they synthesize and secrete1. Because the collagen of cartilage is capable of binding serum fibronectin2 and fibronectin is present in cartilage during its development3, these cells should, in theory, slowly migrate from the synovial lining to the articular surface. It is their absence from the articular cartilage in normal circumstances, and then presence in such pathological states as rheumatoid arthritis, that is striking. We therefore set out to determine whether a component of cartilage could prevent fibroblast adherence in a defined adhesion assay. As normal cartilage is composed of 50% proteoglycans and 50% collagen by dry weight4, we tested the possibility that the proteoglycans in cartilage inhibit fibroblast adhesion to collagen. We present here evidence that fibroblast spreading and adhesion to collagenous substrates is inhibited by cartilage proteoglycans.

  8. Human mast cell neutral proteases generate modified LDL particles with increased proteoglycan binding.

    PubMed

    Maaninka, Katariina; Nguyen, Su Duy; Mäyränpää, Mikko I; Plihtari, Riia; Rajamäki, Kristiina; Lindsberg, Perttu J; Kovanen, Petri T; Öörni, Katariina

    2018-04-13

    Subendothelial interaction of LDL with extracellular matrix drives atherogenesis. This interaction can be strengthened by proteolytic modification of LDL. Mast cells (MCs) are present in atherosclerotic lesions, and upon activation, they degranulate and release a variety of neutral proteases. Here we studied the ability of MC proteases to cleave apoB-100 of LDL and affect the binding of LDL to proteoglycans. Mature human MCs were differentiated from human peripheral blood-derived CD34 + progenitors in vitro and activated with calcium ionophore to generate MC-conditioned medium. LDL was incubated in the MC-conditioned medium or with individual MC proteases, and the binding of native and modified LDL to isolated human aortic proteoglycans or to human atherosclerotic plaques ex vivo was determined. MC proteases in atherosclerotic human coronary artery lesions were detected by immunofluorescence and qPCR. Activated human MCs released the neutral proteases tryptase, chymase, carboxypeptidase A3, cathepsin G, and granzyme B. Of these, cathepsin G degraded most efficiently apoB-100, induced LDL fusion, and enhanced binding of LDL to isolated human aortic proteoglycans and human atherosclerotic lesions ex vivo. Double immunofluoresence staining of human atherosclerotic coronary arteries for tryptase and cathepsin G indicated that lesional MCs contain cathepsin G. In the lesions, expression of cathepsin G correlated with the expression of tryptase and chymase, but not with that of neutrophil proteinase 3. The present study suggests that cathepsin G in human atherosclerotic lesions is largely derived from MCs and that activated MCs may contribute to atherogenesis by enhancing LDL retention. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. SDN-1/Syndecan Acts in Parallel to the Transmembrane Molecule MIG-13 to Promote Anterior Neuroblast Migration.

    PubMed

    Sundararajan, Lakshmi; Norris, Megan L; Lundquist, Erik A

    2015-05-28

    The Q neuroblasts in Caenorhabditis elegans display left-right asymmetry in their migration, with QR and descendants on the right migrating anteriorly, and QL and descendants on the left migrating posteriorly. Initial QR and QL migration is controlled by the transmembrane receptors UNC-40/DCC, PTP-3/LAR, and the Fat-like cadherin CDH-4. After initial migration, QL responds to an EGL-20/Wnt signal that drives continued posterior migration by activating MAB-5/Hox activity in QL but not QR. QR expresses the transmembrane protein MIG-13, which is repressed by MAB-5 in QL and which drives anterior migration of QR descendants. A screen for new Q descendant AQR and PQR migration mutations identified mig-13 as well as hse-5, the gene encoding the glucuronyl C5-epimerase enzyme, which catalyzes epimerization of glucuronic acid to iduronic acid in the heparan sulfate side chains of heparan sulfate proteoglycans (HSPGs). Of five C. elegans HSPGs, we found that only SDN-1/Syndecan affected Q migrations. sdn-1 mutants showed QR descendant AQR anterior migration defects, and weaker QL descendant PQR migration defects. hse-5 affected initial Q migration, whereas sdn-1 did not. sdn-1 and hse-5 acted redundantly in AQR and PQR migration, but not initial Q migration, suggesting the involvement of other HSPGs in Q migration. Cell-specific expression studies indicated that SDN-1 can act in QR to promote anterior migration. Genetic interactions between sdn-1, mig-13, and mab-5 suggest that MIG-13 and SDN-1 act in parallel to promote anterior AQR migration and that SDN-1 also controls posterior migration. Together, our results indicate previously unappreciated complexity in the role of multiple signaling pathways and inherent left-right asymmetry in the control of Q neuroblast descendant migration. Copyright © 2015 Sundararajan et al.

  10. SDN-1/Syndecan Acts in Parallel to the Transmembrane Molecule MIG-13 to Promote Anterior Neuroblast Migration

    PubMed Central

    Sundararajan, Lakshmi; Norris, Megan L.; Lundquist, Erik A.

    2015-01-01

    The Q neuroblasts in Caenorhabditis elegans display left-right asymmetry in their migration, with QR and descendants on the right migrating anteriorly, and QL and descendants on the left migrating posteriorly. Initial QR and QL migration is controlled by the transmembrane receptors UNC-40/DCC, PTP-3/LAR, and the Fat-like cadherin CDH-4. After initial migration, QL responds to an EGL-20/Wnt signal that drives continued posterior migration by activating MAB-5/Hox activity in QL but not QR. QR expresses the transmembrane protein MIG-13, which is repressed by MAB-5 in QL and which drives anterior migration of QR descendants. A screen for new Q descendant AQR and PQR migration mutations identified mig-13 as well as hse-5, the gene encoding the glucuronyl C5-epimerase enzyme, which catalyzes epimerization of glucuronic acid to iduronic acid in the heparan sulfate side chains of heparan sulfate proteoglycans (HSPGs). Of five C. elegans HSPGs, we found that only SDN-1/Syndecan affected Q migrations. sdn-1 mutants showed QR descendant AQR anterior migration defects, and weaker QL descendant PQR migration defects. hse-5 affected initial Q migration, whereas sdn-1 did not. sdn-1 and hse-5 acted redundantly in AQR and PQR migration, but not initial Q migration, suggesting the involvement of other HSPGs in Q migration. Cell-specific expression studies indicated that SDN-1 can act in QR to promote anterior migration. Genetic interactions between sdn-1, mig-13, and mab-5 suggest that MIG-13 and SDN-1 act in parallel to promote anterior AQR migration and that SDN-1 also controls posterior migration. Together, our results indicate previously unappreciated complexity in the role of multiple signaling pathways and inherent left-right asymmetry in the control of Q neuroblast descendant migration. PMID:26022293

  11. Impairment of chondrocyte biosynthetic activity by exposure to 3-tesla high-field magnetic resonance imaging is temporary

    PubMed Central

    Sunk, Ilse-Gerlinde; Trattnig, Siegfried; Graninger, Winfried B; Amoyo, Love; Tuerk, Birgit; Steiner, Carl-Walter; Smolen, Josef S; Bobacz, Klaus

    2006-01-01

    The influence of magnetic resonance imaging (MRI) devices at high field strengths on living tissues is unknown. We investigated the effects of a 3-tesla electromagnetic field (EMF) on the biosynthetic activity of bovine articular cartilage. Bovine articular cartilage was obtained from juvenile and adult animals. Whole joints or cartilage explants were subjected to a pulsed 3-tesla EMF; controls were left unexposed. Synthesis of sulfated glycosaminoglycans (sGAGs) was measured by using [35S]sulfate incorporation; mRNA encoding the cartilage markers aggrecan and type II collagen, as well as IL-1β, were analyzed by RT–PCR. Furthermore, effects of the 3-tesla EMF were determined over the course of time directly after exposure (day 0) and at days 3 and 6. In addition, the influence of a 1.5-tesla EMF on cartilage sGAG synthesis was evaluated. Chondrocyte cell death was assessed by staining with Annexin V and TdT-mediated dUTP nick end labelling (TUNEL). Exposure to the EMF resulted in a significant decrease in cartilage macromolecule synthesis. Gene expression of both aggrecan and IL-1β, but not of collagen type II, was reduced in comparison with controls. Staining with Annexin V and TUNEL revealed no evidence of cell death. Interestingly, chondrocytes regained their biosynthetic activity within 3 days after exposure, as shown by proteoglycan synthesis rate and mRNA expression levels. Cartilage samples exposed to a 1.5-tesla EMF remained unaffected. Although MRI devices with a field strength of more than 1.5 T provide a better signal-to-noise ratio and thereby higher spatial resolution, their high field strength impairs the biosynthetic activity of articular chondrocytes in vitro. Although this decrease in biosynthetic activity seems to be transient, articular cartilage exposed to high-energy EMF may become vulnerable to damage. PMID:16831232

  12. Impairment of chondrocyte biosynthetic activity by exposure to 3-tesla high-field magnetic resonance imaging is temporary.

    PubMed

    Sunk, Ilse-Gerlinde; Trattnig, Siegfried; Graninger, Winfried B; Amoyo, Love; Tuerk, Birgit; Steiner, Carl-Walter; Smolen, Josef S; Bobacz, Klaus

    2006-01-01

    The influence of magnetic resonance imaging (MRI) devices at high field strengths on living tissues is unknown. We investigated the effects of a 3-tesla electromagnetic field (EMF) on the biosynthetic activity of bovine articular cartilage. Bovine articular cartilage was obtained from juvenile and adult animals. Whole joints or cartilage explants were subjected to a pulsed 3-tesla EMF; controls were left unexposed. Synthesis of sulfated glycosaminoglycans (sGAGs) was measured by using [35S]sulfate incorporation; mRNA encoding the cartilage markers aggrecan and type II collagen, as well as IL-1beta, were analyzed by RT-PCR. Furthermore, effects of the 3-tesla EMF were determined over the course of time directly after exposure (day 0) and at days 3 and 6. In addition, the influence of a 1.5-tesla EMF on cartilage sGAG synthesis was evaluated. Chondrocyte cell death was assessed by staining with Annexin V and TdT-mediated dUTP nick end labelling (TUNEL). Exposure to the EMF resulted in a significant decrease in cartilage macromolecule synthesis. Gene expression of both aggrecan and IL-1beta, but not of collagen type II, was reduced in comparison with controls. Staining with Annexin V and TUNEL revealed no evidence of cell death. Interestingly, chondrocytes regained their biosynthetic activity within 3 days after exposure, as shown by proteoglycan synthesis rate and mRNA expression levels. Cartilage samples exposed to a 1.5-tesla EMF remained unaffected. Although MRI devices with a field strength of more than 1.5 T provide a better signal-to-noise ratio and thereby higher spatial resolution, their high field strength impairs the biosynthetic activity of articular chondrocytes in vitro. Although this decrease in biosynthetic activity seems to be transient, articular cartilage exposed to high-energy EMF may become vulnerable to damage.

  13. Effect of Impaction Sequence on Osteochondral Graft Damage: The Role of Repeated and Varying Loads

    PubMed Central

    Kang, Richard W.; Friel, Nicole A.; Williams, James M.; Cole, Brian J.; Wimmer, Markus A.

    2013-01-01

    Background Osteochondral autografts and allografts require mechanical force for proper graft placement into the defect site; however, impaction compromises the tissue. This study aimed to determine the effect of impaction force and number of hits to seat the graft on cartilage integrity. Hypothesis Under constant impulse conditions, higher impaction load magnitudes are more detrimental to cell viability, matrix integrity and collagen network organization and will result in proteoglycan loss and nitric oxide release. Study Design Controlled laboratory study Methods Osteochondral explants, harvested from fresh bovine trochleas, were exposed to a series of consistent impact loads delivered by a pneumatically driven device. Each plug received the same overall impulse of 7 Ns, reflecting the mean of 23 clinically inserted plugs. Impaction loads of 37.5N, 75N, 150N, and 300N were matched with 74, 37, 21, and 11 hits respectively. Following impaction, the plugs were harvested and cartilage was analyzed for cell viability, histology by safranin-o and picosirius red, and release of sulfated glycosaminoglycans and nitric oxide. Data were compared with non-impacted control. Results Impacted plugs had significantly lower cell viability than non-impacted plugs. A dose response relationship in loss of cell viability with respect to load magnitude was seen immediately and after 4 days but lost after 8 days. Histologic analysis revealed intact cartilage surface in all samples (loaded or control), with loaded samples showing alterations in birefringence. While the sulfated GAG release was similar across varying impaction loads, release of nitric oxide increased with increasing impaction magnitudes and time. Conclusions Impaction loading parameters have a direct effect on the time course of the viability of the cartilage in the graft tissue. Clinical Relevance Optimal loading parameters for surgical impaction of osteochondral grafts are those with lower load magnitudes and a greater number of hits to ensure proper fit. PMID:19915099

  14. Micro- and Nanomechanical Analysis of Articular Cartilage by Indentation-Type Atomic Force Microscopy: Validation with a Gel-Microfiber Composite

    PubMed Central

    Loparic, Marko; Wirz, Dieter; Daniels, A.U.; Raiteri, Roberto; VanLandingham, Mark R.; Guex, Geraldine; Martin, Ivan; Aebi, Ueli; Stolz, Martin

    2010-01-01

    Abstract As documented previously, articular cartilage exhibits a scale-dependent dynamic stiffness when probed by indentation-type atomic force microscopy (IT-AFM). In this study, a micrometer-size spherical tip revealed an unimodal stiffness distribution (which we refer to as microstiffness), whereas probing articular cartilage with a nanometer-size pyramidal tip resulted in a bimodal nanostiffness distribution. We concluded that indentation of the cartilage's soft proteoglycan (PG) gel gave rise to the lower nanostiffness peak, whereas deformation of its collagen fibrils yielded the higher nanostiffness peak. To test our hypothesis, we produced a gel-microfiber composite consisting of a chondroitin sulfate-containing agarose gel and a fibrillar poly(ethylene glycol)-terephthalate/poly(butylene)-terephthalate block copolymer. In striking analogy to articular cartilage, the microstiffness distribution of the synthetic composite was unimodal, whereas its nanostiffness exhibited a bimodal distribution. Also, similar to the case with cartilage, addition of the negatively charged chondroitin sulfate rendered the gel-microfiber composite's water content responsive to salt. When the ionic strength of the surrounding buffer solution increased from 0.15 to 2 M NaCl, the cartilage's microstiffness increased by 21%, whereas that of the synthetic biomaterial went up by 31%. When the nanostiffness was measured after the ionic strength was raised by the same amount, the cartilage's lower peak increased by 28%, whereas that of the synthetic biomaterial went up by 34%. Of interest, the higher peak values remained unchanged for both materials. Taken together, these results demonstrate that the nanoscale lower peak is a measure of the soft PG gel, and the nanoscale higher peak measures collagen fibril stiffness. In contrast, the micrometer-scale measurements fail to resolve separate stiffness values for the PG and collagen fibril moieties. Therefore, we propose to use nanostiffness as a new biomarker to analyze structure-function relationships in normal, diseased, and engineered cartilage. PMID:20513418

  15. Polymerized laminin-332 matrix supports rapid and tight adhesion of keratinocytes, suppressing cell migration.

    PubMed

    Kariya, Yoshinobu; Sato, Hiroki; Katou, Naoko; Kariya, Yukiko; Miyazaki, Kaoru

    2012-01-01

    Laminin-332 (α3ß3γ2) (Lm332) supports the stable anchoring of basal keratinocytes to the epidermal basement membrane, while it functions as a motility factor for wound healing and cancer invasion. To understand these contrasting activities of Lm332, we investigated Lm332 matrices deposited by normal human keratinocytes and other Lm332-expressing cell lines. All types of the cells efficiently deposited Lm332 on the culture plates in specific patterns. On the contrary, laminins containing laminin ß1 and/or γ1 chains, such as Lm511 and Lm311, were not deposited on the culture plates even if secreted into culture medium. The Lm332 deposition was not inhibited by function-blocking antibodies to the α3 and α6 integrins but was inhibited by sodium selenate, suggesting that sulfated glycosaminoglycans on cell surface, e.g. heparan sulfate proteoglycans, might be involved in the process. HEK293 cells overexpressing exogenous Lm332 (Lm332-HEK) almost exclusively deposited Lm332 on the plates. The deposited Lm332 matrix showed a mesh-like network structure as analyzed by electron microscopy, suggesting that Lm332 was highly polymerized. When biological activity was analyzed, the Lm332 matrix rather suppressed the migration of keratinocytes as compared with purified Lm332, which highly promoted the cell migration. The Lm332 matrix supported adhesion of keratinocytes much more strongly and stably than purified Lm332. Integrin α3ß1 bound to the Lm332 matrix at a three times higher level than purified Lm332. Normal keratinocytes prominently showed integrin α6ß4-containing, hemidesmosome-like structures on the Lm332 matrix but not on the purified one. These results indicate that the polymerized Lm332 matrix supports stable cell adhesion by interacting with both integrin α6ß4 and α3ß1, whereas unassembled soluble Lm332 supports cell migration.

  16. Role of proteoglycans in neuro-inflammation and central nervous system fibrosis.

    PubMed

    Heindryckx, Femke; Li, Jin-Ping

    2018-01-31

    Fibrosis is defined as the thickening and scarring of connective tissue, usually as a consequence of tissue damage. The central nervous system (CNS) is special in the sense that fibrogenic cells are restricted to vascular and meningeal areas. Inflammation and the disruption of the blood-brain barrier can lead to the infiltration of fibroblasts and trigger fibrotic response. While the initial function of the fibrotic tissue is to restore the blood-brain barrier and to limit the site of injury, it also demolishes the structure of extracellular matrix and impedes the healing process by producing inhibitory molecules and forming a physical and biochemical barrier that prevents axon regeneration. As a major constituent in the extracellular matrix, proteoglycans participate in the neuro-inflammation, modulating the fibrotic process. In this review, we will discuss the pathophysiology of fibrosis during acute injuries of the CNS, as well as during chronic neurodegenerative conditions such as Alzheimer's disease, Parkinson's disease, multiple sclerosis and age-related neurodegeneration with focus on the functional roles of proteoglycans. Copyright © 2017 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.

  17. Anti-diabetic effects of Ganoderma lucidum.

    PubMed

    Ma, Haou-Tzong; Hsieh, Jung-Feng; Chen, Shui-Tein

    2015-06-01

    Ganoderma lucidum is a white rot fungus widely used as a tonic for the promotion of longevity and health. Extracts of G. lucidum have been recognized as an alternative adjuvant treatment for diabetes. Among the many biologically active constituents of G. lucidum, polysaccharides, proteoglycans, proteins and triterpenoids have been shown to have hypoglycemic effects. G. lucidum polysaccharides have been reported to have hypoglycemic activity by increasing plasma insulin levels and decreasing plasma sugar levels in mice. Protein tyrosine phosphatase 1B is a promising therapeutic target in diabetes, and G. lucidum proteoglycan can inhibit this enzyme in vitro. Moreover, G. lucidum triterpenoids were shown to have inhibitory activity on aldose reductase and α-glucosidase that can suppress postprandial hyperglycemia. In addition, a protein Ling Zhi-8 extracted from G. lucidum significantly decreased lymphocyte infiltration and increased the antibody detection of insulin in diabetic mice. This review summarizes most of the research about the hypoglycemic action effects of polysaccharides, proteoglycans, proteins and tritrerpenoids from G. lucidum as a guide for future research. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. A Role for Serglycin Proteoglycan in Mast Cell Apoptosis Induced by a Secretory Granule-mediated Pathway*

    PubMed Central

    Melo, Fabio Rabelo; Waern, Ida; Rönnberg, Elin; Åbrink, Magnus; Lee, David M.; Schlenner, Susan M.; Feyerabend, Thorsten B.; Rodewald, Hans-Reimer; Turk, Boris; Wernersson, Sara; Pejler, Gunnar

    2011-01-01

    Mast cell secretory granules (secretory lysosomes) contain large amounts of fully active proteases bound to serglycin proteoglycan. Damage to the granule membrane will thus lead to the release of serglycin and serglycin-bound proteases into the cytosol, which potentially could lead to proteolytic activation of cytosolic pro-apoptotic compounds. We therefore hypothesized that mast cells are susceptible to apoptosis induced by permeabilization of the granule membrane and that this process is serglycin-dependent. Indeed, we show that wild-type mast cells are highly sensitive to apoptosis induced by granule permeabilization, whereas serglycin-deficient cells are largely resistant. The reduced sensitivity of serglycin−/− cells to apoptosis was accompanied by reduced granule damage, reduced release of proteases into the cytosol, and defective caspase-3 activation. Mechanistically, the apoptosis-promoting effect of serglycin involved serglycin-dependent proteases, as indicated by reduced sensitivity to apoptosis and reduced caspase-3 activation in cells lacking individual mast cell-specific proteases. Together, these findings implicate serglycin proteoglycan as a novel player in mast cell apoptosis. PMID:21123167

  19. Synthetic Xylosides: Probing the Glycosaminoglycan Biosynthetic Machinery for Biomedical Applications.

    PubMed

    Chua, Jie Shi; Kuberan, Balagurunathan

    2017-11-21

    Glycosaminoglycans (GAGs) are polysaccharides ubiquitously found on cell surfaces and in the extracellular matrix (ECM). They regulate numerous cellular signaling events involved in many developmental and pathophysiological processes. GAGs are composed of complex sequences of repeating disaccharide units, each of which can carry many different modifications. The tremendous structural variations account for their ability to bind many proteins and thus, for their numerous functions. Although the sequence of GAG biosynthetic events and the enzymes involved mostly were deduced a decade ago, the emergence of tissue or cell specific GAGs from a nontemplate driven process remains an enigma. Current knowledge favors the hypothesis that macromolecular assemblies of GAG biosynthetic enzymes termed "GAGOSOMEs" coordinate polymerization and fine structural modifications in the Golgi apparatus. Distinct GAG structures arise from the differential channeling of substrates through the Golgi apparatus to various GAGOSOMEs. As GAGs perform multiple regulatory roles, it is of great interest to develop molecular strategies to selectively interfere with GAG biosynthesis for therapeutic applications. In this Account, we assess our present knowledge on GAG biosynthesis, the manipulation of GAG biosynthesis using synthetic xylosides, and the unrealized potential of these xylosides in various biomedical applications. Synthetic xylosides are small molecules consisting of a xylose attached to an aglycone group, and they compete with endogenous proteins for precursors and biosynthetic enzymes to assemble GAGs. This competition reduces endogenous proteoglycan-bound GAGs while increasing xyloside-bound free GAGs, mostly chondroitin sulfate (CS) and less heparan sulfate (HS), resulting in a variety of biological consequences. To date, hundreds of xylosides have been published and the importance of the aglycone group in determining the structure of the primed GAG chains is well established. However, the structure-activity relationship has long been cryptic. Nonetheless, xylosides have been designed to increase HS priming, modified to inhibit endogenous GAG production without priming, and engineered to be more biologically relevant. Synthetic xylosides hold great promise in many biomedical applications and as therapeutics. They are small, orally bioavailable, easily excreted, and utilize the host cell biosynthetic machinery to assemble GAGs that are likely nonimmunogenic. Various xylosides have been shown, in different biological systems, to have anticoagulant effects, selectively kill tumor cells, abrogate angiogenic and metastatic pathways, promote angiogenesis and neuronal growth, and affect embryonic development. However, most of these studies utilized the commercially available one or two β-D-xylosides and focused on the impact of endogenous proteoglycan-bound GAG inhibition on biological activity. Nevertheless, the manipulation of cell behavior as a result of stabilizing growth factor signaling with xyloside-primed GAGs is also reckonable but underexplored. Recent advances in the use of molecular modeling and docking simulations to understand the structure-activity relationships of xylosides have opened up the possibility of a more rational aglycone design to achieve a desirable biological outcome through selective priming and inhibitory activities. We envision these advances will encourage more researchers to explore these fascinating xylosides, harness the GAG biosynthetic machinery for a wider range of biomedical applications, and accelerate the successful transition of xyloside-based therapeutics from bench to bedside.

  20. Effect of disulfide bonding and multimerization on proteoglycan 4's cartilage boundary lubricating ability and adsorption.

    PubMed

    Abubacker, Saleem; Ponjevic, Dragana; Ham, Hyun O; Messersmith, Phillip B; Matyas, John R; Schmidt, Tannin A

    2016-01-01

    The objectives of this study were to assess the cartilage boundary lubricating ability of (1) nonreduced (NR) disulfide-bonded proteoglycan 4 (PRG4) multimers versus PRG4 monomers and (2) NR versus reduced and alkylated (R/A) PRG4 monomers and to assess (3) the ability of NR PRG4 multimers versus monomers to adsorb to an articular cartilage surface. PRG4 was separated into two preparations, PRG4 multimer enriched (PRG4Multi+) and PRG4 multimer deficient (PRG4Multi-), using size exclusion chromatography (SEC) and characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The cartilage boundary lubricating ability of PRG4Multi+ and PRG4Multi- was compared at a physiological concentration (450 μg/mL) and assessed over a range of concentrations (45, 150, and 450 μg/mL). R/A and NR PRG4Multi- were evaluated at 450 μg/mL. Immunohistochemistry with anti-PRG4 antibody 4D6 was performed to visualize the adsorption of PRG4 preparations to the surface of articular cartilage explants. Separation into enriched populations of PRG4Multi+ and PRG4Multi- was achieved using SEC and was confirmed by SDS-PAGE. PRG4Multi+ and PRG4Multi- both functioned as effective friction-reducing cartilage boundary lubricants at 450 μg/mL, with PRG4Multi+ being more effective than PRG4Multi-. PRG4Multi+ lubricated in a dose-dependent manner, however, PRG4Multi- did not. R/A PRG4Multi- lubricated similar to NR PRG4Multi-. PRG4-containing solutions showed 4D6 immunoreactivity at the articular surface; the immunoreactive intensity of PRG4Multi+ appeared to be similar to SF, whereas PRG4Multi- appeared to have less intensity. These results demonstrate that the intermolecular disulfide-bonded multimeric structure of PRG4 is important for its ability to adsorb to a cartilage surface and function as a boundary lubricant. These findings contribute to a greater understanding of the molecular basis of cartilage boundary lubrication of PRG4. Elucidating the PRG4 structure-lubrication function relationship will further contribute to the understanding of PRG4's role in diarthrodial joint homeostasis and disease.

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