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Sample records for acid oa dinophysistoxins

  1. Structure–Activity Relationship Studies Using Natural and Synthetic Okadaic Acid/Dinophysistoxin Toxins

    PubMed Central

    Twiner, Michael J.; Doucette, Gregory J.; Pang, Yucheng; Fang, Chao; Forsyth, Craig J.; Miles, Christopher O.

    2016-01-01

    Okadaic acid (OA) and the closely related dinophysistoxins (DTXs) are algal toxins that accumulate in shellfish and are known serine/threonine protein phosphatase (ser/thr PP) inhibitors. Phosphatases are important modulators of enzyme activity and cell signaling pathways. However, the interactions between the OA/DTX toxins and phosphatases are not fully understood. This study sought to identify phosphatase targets and characterize their structure–activity relationships (SAR) with these algal toxins using a combination of phosphatase activity and cytotoxicity assays. Preliminary screening of 21 human and yeast phosphatases indicated that only three ser/thr PPs (PP2a, PP1, PP5) were inhibited by physiologically saturating concentrations of DTX2 (200 nM). SAR studies employed naturally-isolated OA, DTX1, and DTX2, which vary in degree and/or position of methylation, in addition to synthetic 2-epi-DTX2. OA/DTX analogs induced cytotoxicity and inhibited PP activity with a relatively conserved order of potency: OA = DTX1 ≥ DTX2 >> 2-epi-DTX. The PPs were also differentially inhibited with sensitivities of PP2a > PP5 > PP1. These findings demonstrate that small variations in OA/DTX toxin structures, particularly at the head region (i.e., C1/C2), result in significant changes in toxicological potency, whereas changes in methylation at C31 and C35 (tail region) only mildly affect potency. In addition to this being the first study to extensively test OA/DTX analogs’ activities towards PP5, these data will be helpful for accurately determining toxic equivalence factors (TEFs), facilitating molecular modeling efforts, and developing highly selective phosphatase inhibitors. PMID:27827901

  2. LC-MS/MS analysis of diarrhetic shellfish poisoning (DSP) toxins, okadaic acid and dinophysistoxin analogues, and other lipophilic toxins.

    PubMed

    Suzuki, Toshiyuki; Quilliam, Michael A

    2011-01-01

    Diarrhetic shellfish poisoning (DSP) is a severe gastrointestinal illness caused by consumption of shellfish contaminated with DSP toxins that are originally produced by toxic dinoflagellates. Based on their structures, DSP toxins were initially classified into three groups, okadaic acid (OA)/dinophysistoxin (DTX) analogues, pectenotoxins (PTXs), and yessotoxins (YTXs). Because PTXs and YTXs have been subsequently shown to have no diarrhetic activities, PTXs and YTXs have recently been eliminated from the definition of DSP toxins. Mouse bioassay (MBA), which is the official testing method of DSP in Japan and many countries, also detects PTXs and YTXs, and thus alternative testing methods detecting only OA/DTX analogues are required in DSP monitoring. Electrospray ionization (ESI) liquid chromatography-mass spectrometry (LC-MS) is a very powerful tool for the detection, identification and quantification of DSP and other lipophilic toxins. In the present review, application of ESI LC-MS techniques to the analysis of each toxin group is described.

  3. Sublethal doses of dinophysistoxin-1 and okadaic acid stimulate secretion of inflammatory factors on innate immune cells: Negative health consequences.

    PubMed

    Del Campo, Miguel; Zhong, Ta-Ying; Tampe, Ricardo; García, Lorena; Lagos, Néstor

    2017-02-01

    One of the proposed mechanisms to explain why Diarrhetic Shellfish Poison (DSP) toxins are tumor promoters is founded on the capacity of these toxins to increase TNF-α secretion. Although macrophages are the principal cells in the activation of the inflammatory response, the immune profile that Okadaic acid (OA) and Dinophysistoxin-1 (DTX-1) trigger in these cells has not been fully explored. We have therefore investigated the effect of various concentrations of both toxins on the activity of several inflammatory factors. Our results demonstrate that OA and DTX-1, at sublethal doses, stimulate secretion of inflammatory factors. Nevertheless DTX-1 was more potent than OA in increasing TNF-α and IL-6 as well as their dependent chemokines KC, MCP-1, LIX, MIP-1 α, MIP-1 β and MIP-2. On the other hand, secretion of IFN-γ and the anti-inflammatory cytokines, IL-4 and IL-10, was unaffected. In addition, DTX-1 also raises matrix metalloproteinase-9 (MMP-9) activity. In this study, for the first time the effect of OA and DTX-1 over the secretion of pro-inflammatory and carcinogenic signals in macrophages are compared, showing that DTX-1 is ten times more potent that OA. The inflammatory profile produced by DTX-1 is shown for the first time. The safe limit regulation should be changed to DSP toxins zero tolerance in the shellfish to be consumed by humans.

  4. In vitro bioaccessibility of the marine biotoxins okadaic acid, dinophysistoxin-2 and their 7-O-acyl fatty acid ester derivatives in raw and steamed shellfish.

    PubMed

    Manita, Diana; Alves, Ricardo N; Braga, Ana Catarina; Fogaça, Fabiola H S; Marques, António; Costa, Pedro Reis

    2017-03-01

    Okadaic acid (OA), Dinophysistoxins (DTX1 and DTX2) and their acyl-derivatives (DTX3) are marine toxins responsible for the human diarrhetic shellfish poisoning. To date the amount of toxins ingested from consumption of shellfish has been considered equal to the amount of toxins available for uptake by the human body. The aim of this study is to assess the OA, DTX2 and DTX3 fractions released from raw and steamed mussels and cockles into the digestive fluids (bioaccessibility) using a static in vitro digestion model. Higher bioaccessibility was found in mussels (86 ± 4%) than in cockles (59 ± 9%). A significant reduction of ester derivatives of OA and an increase of OA were observed in the bioaccessible fraction of mussel samples, suggesting that DTX3 undergo conversion into their more toxic parent compounds during human digestion. However, similar increase of DTX2 and reduction of the respective acyl derivatives was not observed. Steaming lead to significant reduction of OA and analogues bioaccessibility in both species even though increased concentrations of toxins are obtained after this treatment. Risk assessment based solely on DSP toxins occurrence in seafood can conduct to an overestimation of the exposure and lead to more conservative regulatory measures.

  5. Evaluation of the Impact of Mild Steaming and Heat Treatment on the Concentration of Okadaic Acid, Dinophysistoxin-2 and Dinophysistoxin-3 in Mussels.

    PubMed

    Rodríguez, Inés; Alfonso, Amparo; Antelo, Alvaro; Alvarez, Mercedes; Botana, Luis M

    2016-06-06

    This study explores the effect of laboratory and industrial steaming on mussels with toxin concentrations above and below the legal limit. We used mild conditions for steaming, 100 °C for 5 min in industrial processing, and up to 20 min in small-scale laboratory steaming. Also, we studied the effect of heat on the toxin concentration of mussels obtained from two different locations and the effect of heat on the levels of dinophysistoxins 3 (DTX3) in both the mussel matrix and in pure form (7-O-palmitoyl okadaic ester and 7-O-palmytoleyl okadaic ester). The results show that the loss of water due to steaming was very small with a maximum of 9.5%, that the toxin content remained unchanged with no concentration effect or increase in toxicity, and that dinophysistoxins 3 was hydrolyzed or degraded to a certain extent under heat treatment. The use of liquid-certified matrix showed a 55% decrease of dinophysistoxins 3 after 10 min steaming, and a 50% reduction in total toxicity after treatment with an autoclave (121 °C for 20 min).

  6. Evaluation of the Impact of Mild Steaming and Heat Treatment on the Concentration of Okadaic Acid, Dinophysistoxin-2 and Dinophysistoxin-3 in Mussels

    PubMed Central

    Rodríguez, Inés; Alfonso, Amparo; Antelo, Alvaro; Alvarez, Mercedes; Botana, Luis M.

    2016-01-01

    This study explores the effect of laboratory and industrial steaming on mussels with toxin concentrations above and below the legal limit. We used mild conditions for steaming, 100 °C for 5 min in industrial processing, and up to 20 min in small-scale laboratory steaming. Also, we studied the effect of heat on the toxin concentration of mussels obtained from two different locations and the effect of heat on the levels of dinophysistoxins 3 (DTX3) in both the mussel matrix and in pure form (7-O-palmitoyl okadaic ester and 7-O-palmytoleyl okadaic ester). The results show that the loss of water due to steaming was very small with a maximum of 9.5%, that the toxin content remained unchanged with no concentration effect or increase in toxicity, and that dinophysistoxins 3 was hydrolyzed or degraded to a certain extent under heat treatment. The use of liquid-certified matrix showed a 55% decrease of dinophysistoxins 3 after 10 min steaming, and a 50% reduction in total toxicity after treatment with an autoclave (121 °C for 20 min). PMID:27275833

  7. Experimental Basis for the High Oral Toxicity of Dinophysistoxin 1: A Comparative Study of DSP

    PubMed Central

    Fernández, Diego A.; Louzao, M. Carmen; Fraga, María; Vilariño, Natalia; Vieytes, Mercedes R.; Botana, Luis M.

    2014-01-01

    Okadaic acid (OA) and its analogues, dinophysistoxin 1 (DTX1) and dinophysistoxin 2 (DTX2), are lipophilic and heat-stable marine toxins produced by dinoflagellates, which can accumulate in filter-feeding bivalves. These toxins cause diarrheic shellfish poisoning (DSP) in humans shortly after the ingestion of contaminated seafood. Studies carried out in mice indicated that DSP poisonous are toxic towards experimental animals with a lethal oral dose 2–10 times higher than the intraperitoneal (i.p.) lethal dose. The focus of this work was to study the absorption of OA, DTX1 and DTX2 through the human gut barrier using differentiated Caco-2 cells. Furthermore, we compared cytotoxicity parameters. Our data revealed that cellular viability was not compromised by toxin concentrations up to 1 μM for 72 h. Okadaic acid and DTX2 induced no significant damage; nevertheless, DTX1 was able to disrupt the integrity of Caco-2 monolayers at concentrations above 50 nM. In addition, confocal microscopy imaging confirmed that the tight-junction protein, occludin, was affected by DTX1. Permeability assays revealed that only DTX1 was able to significantly cross the intestinal epithelium at concentrations above 100 nM. These data suggest a higher oral toxicity of DTX1 compared to OA and DTX2. PMID:24394641

  8. Experimental basis for the high oral toxicity of dinophysistoxin 1: a comparative study of DSP.

    PubMed

    Fernández, Diego A; Louzao, M Carmen; Fraga, María; Vilariño, Natalia; Vieytes, Mercedes R; Botana, Luis M

    2014-01-03

    Okadaic acid (OA) and its analogues, dinophysistoxin 1 (DTX1) and dinophysistoxin 2 (DTX2), are lipophilic and heat-stable marine toxins produced by dinoflagellates, which can accumulate in filter-feeding bivalves. These toxins cause diarrheic shellfish poisoning (DSP) in humans shortly after the ingestion of contaminated seafood. Studies carried out in mice indicated that DSP poisonous are toxic towards experimental animals with a lethal oral dose 2-10 times higher than the intraperitoneal (i.p.) lethal dose. The focus of this work was to study the absorption of OA, DTX1 and DTX2 through the human gut barrier using differentiated Caco-2 cells. Furthermore, we compared cytotoxicity parameters. Our data revealed that cellular viability was not compromised by toxin concentrations up to 1 μM for 72 h. Okadaic acid and DTX2 induced no significant damage; nevertheless, DTX1 was able to disrupt the integrity of Caco-2 monolayers at concentrations above 50 nM. In addition, confocal microscopy imaging confirmed that the tight-junction protein, occludin, was affected by DTX1. Permeability assays revealed that only DTX1 was able to significantly cross the intestinal epithelium at concentrations above 100 nM. These data suggest a higher oral toxicity of DTX1 compared to OA and DTX2.

  9. Inhibition equivalency factors for dinophysistoxin-1 and dinophysistoxin-2 in protein phosphatase assays: applicability to the analysis of shellfish samples and comparison with LC-MS/MS.

    PubMed

    Garibo, Diana; de la Iglesia, Pablo; Diogène, Jorge; Campàs, Mònica

    2013-03-13

    The protein phosphatase inhibition assay (PPIA) is a well-known strategy for the determination of diarrheic shellfish poisoning (DSP) lipophilic toxins, which deserves better characterization and understanding to be used as a routine screening tool in monitoring programs. In this work, the applicability of two PPIAs to the determination of okadaic acid (OA), dinophysistoxin-1 (DTX-1), dinophysistoxin-2 (DTX-2), and their acyl ester derivatives in shellfish has been investigated. The inhibitory potencies of the DSP toxins on a recombinant and a wild PP2A have been determined, allowing the establishment of inhibition equivalency factors (IEFs) (1.1 and 0.9 for DTX-1, and 0.4 and 0.6 for DTX-2, for recombinant and wild PP2A, respectively). The PPIAs have been applied to the determination of OA equivalent contents in spiked and naturally contaminated shellfish samples. Results have been compared to those obtained by LC-MS/MS analysis, after application of the IEFs, showing good agreements.

  10. Structural Basis for the Reduced Toxicity of Dinophysistoxin-2

    SciTech Connect

    Huhn, J.; Jeffrey, F; Larsen, K; Rundberget, T; Rise, F; Cox, N; Arcus, V; Shi, Y; Miles, C

    2009-01-01

    Okadaic acid (OA), dinophysistoxin-1 (DTX-1), and dinophysistoxin-2 (DTX-2) are algal toxins that can accumulate in shellfish and cause diarrhetic shellfish poisoning. Recent studies indicate that DTX-2 is about half as toxic and has about half the affinity for protein phosphatase 2A (PP2A) as OA. NMR structural studies showed that DTX-1 possessed an equatorial 35-methyl group but that DTX-2 had an axial 35-methyl group. Molecular modeling studies indicated that an axial 35-methyl could exhibit unfavorable interactions in the PP2A binding site, and this has been proposed as the reason for the reduced toxicity of DTX-2. Statistical analyses of published data indicate that the affinity of PP2A for DTX-1 is 1.6-fold higher, and for DTX-2 is 2-fold lower, than for OA. We obtained X-ray crystal structures of DTX-1 and DTX-2 bound to PP2A. The crystal structures independently confirm the C-35 stereochemistries determined in the earlier NMR study. The structure for the DTX-1 complex was virtually identical to that of the OA-PP2A complex, except for the presence of the equatorial 35-methyl on the ligand. The favorable placement of the equatorial 35-methyl group of DTX-1 against the aromatic {pi}-bonds of His191 may account for the increased affinity of PP2A toward DTX-1. In contrast, the axial 35-methyl of DTX-2 caused the side chain of His191 to rotate 140{sup o} so that it pointed toward the solvent, thereby opening one end of the hydrophobic binding cage. This rearrangement to accommodate the unfavorable interaction from the axial 35-methyl of DTX-2 reduces the binding energy and appears to be responsible for the reduced affinity of PP2A for DTX-2. These results highlight the potential of molecular modeling studies for understanding the relative toxicity of analogues once the binding site at the molecular target has been properly characterized.

  11. Differential dynamics of dinophysistoxins and pectenotoxins between blue mussel and common cockle: a phenomenon originating from the complex toxin profile of Dinophysis acuta.

    PubMed

    Vale, Paulo

    2004-08-01

    Different toxin profiles of dinophysistoxins and pectenotoxins have been reported before between blue mussel and other bivalve species, such as common cockle, razor clam, clams, etc. Comparison of toxins present in plankton in mussel growing areas and in cockle growing areas, respectively, showed there was no particular incidence of dinophysistoxin-2 (DTX2) in plankton from mussel growing areas that could account for the higher percentage of DTX2 in relation to okadaic acid (OA) found in mussels; or of pectenotoxin-2 in cockle growing areas that could explain the higher levels of pectenotoxin-2 seco acid (PTX2sa) found in cockles. A detoxification experiment between mussels and cockles showed the higher percentage of DTX2 in mussels was due to slower elimination of this toxin in relation to OA; while the lower levels of PTX2sa were due to quicker elimination by mussels than by cockles. The slower elimination of DTX2 explains why in late summer and autumn this toxin gradually accumulate in mussels throughout the entire coast, while other bivalves species have a lower percentage of DTX2, very close to the 3:2 OA:DTX2 ratio found in natural plankton assemblages when Dinophysis acuta predominates. In the clam Donax spp., DTX2 concentration also tends to build up in relation to OA, this being made up predominantly by free DTX2 while esterified DTX2 is found only in trace levels (similarly to what is found in mussel for DTX2). We hypothesise that the esterified forms of OA and DTX2 are more easily eliminated than the free forms, by all shellfish species. The free forms are more difficult to eliminate. This is particularly notable in these two species that present a very low conversion of DTX2 into acyl esters. The high pool of free toxins is partially responsible for these two species (mussel and Donax clams) being the sentinel species for DSP contamination throughout the Portuguese coast. Esters of OA and DTX2 were found in a plankton sample where D. acuta was the

  12. Effects of tiaprofenic acid on plasminogen activators and inhibitors in human OA and RA synovium.

    PubMed

    Pelletier, J P; McCollum, R; Cloutier, J M; Martel-Pelletier, J

    1992-01-01

    The effect of therapeutic and pharmacological concentrations of tiaprofenic acid, a non-steroidal anti-inflammatory drug (NSAID), on the synthesis of the plasminogen activators, urokinase plasminogen activator (uPA) and tissue plasminogen activator (tPA), and the plasminogen activator inhibitors 1 and 2 (PAI-1 and PAI-2), by human synovial membranes isolated from osteoarthritis (OA) and rheumatoid arthritis (RA) sufferers was evaluated. Both forms of plasminogen activator (PA) and PA inhibitor (PAI) were synthesized by the arthritic synovium. PAI-1 and PAI-2 were both synthesized in greater amounts than the plasminogen activators. Tiaprofenic acid induced a dose-dependent decrease in uPA synthesis in both OA and RA, particularly in OA synovium, but had no true effect on tPA. Tiaprofenic acid also exerted a suppressive effect on the synthesis of PAI-1 in both OA and RA synovial membranes, and on the release of PAI-2 in RA synovium. The results of this study indicate that a decrease in uPA synthesis may be one of the mechanisms by which tiaprofenic acid could exert its effects on the arthritic process. The suppressive action of tiaprofenic acid on PAI is not likely to have a significant impact on the balance of plasminogen activators and plasminogen activator inhibitors, as plasminogen activator inhibitors are synthesized in greater amounts than plasminogen activators.

  13. Oleanolic acid (OA) as an antileishmanial agent: Biological evaluation and in silico mechanistic insights.

    PubMed

    Melo, Tahira Souza; Gattass, Cerli Rocha; Soares, Deivid Costa; Cunha, Micael Rodrigues; Ferreira, Christian; Tavares, Maurício Temotheo; Saraiva, Elvira; Parise-Filho, Roberto; Braden, Hannah; Delorenzi, Jan Carlo

    2016-06-01

    Although a worldwide health problem, leishmaniasis is considered a highly neglected disease, lacking efficient and low toxic treatment. The efforts for new drug development are based on alternatives such as new uses for well-known drugs, in silico and synthetic studies and naturally derived compounds. Oleanolic acid (OA) is a pentacyclic triterpenoid widely distributed throughout the Plantae kingdom that displays several pharmacological activities. OA showed potent leishmancidal effects in different Leishmania species, both against promastigotes (IC(50 L. braziliensis) 30.47 ± 6.35 μM; IC(50 L. amazonensis) 40.46 ± 14.21 μM; IC(50 L. infantum) 65.93 ± 15.12 μM) and amastigotes (IC(50 L. braziliensis) 68.75 ± 16.55 μM; IC(50 L. amazonensis) 38.45 ± 12.05 μM; IC(50 L. infantum) 64.08 ± 23.52 μM), with low cytotoxicity against mouse peritoneal macrophages (CC(50) 235.80 ± 36.95 μM). Moreover, in silico studies performed to evaluate OA molecular properties and to elucidate the possible mechanism of action over the Leishmania enzyme sterol 14α-demethylase (CYP51) suggested that OA interacts efficiently with CYP51 and could inhibit the ergosterol synthesis pathway. Collectively, these data indicate that OA is a good candidate as leading compound for the development of a new leishmaniasis treatment.

  14. OAS proteins and cGAS: unifying concepts in sensing and responding to cytosolic nucleic acids.

    PubMed

    Hornung, Veit; Hartmann, Rune; Ablasser, Andrea; Hopfner, Karl-Peter

    2014-08-01

    Recent discoveries in the field of innate immunity have highlighted the existence of a family of nucleic acid-sensing proteins that have similar structural and functional properties. These include the well-known oligoadenylate synthase (OAS) family proteins and the recently identified OAS homologue cyclic GMP-AMP (cGAMP) synthase (cGAS). The OAS proteins and cGAS are template-independent nucleotidyltransferases that, once activated by double-stranded nucleic acids in the cytosol, produce unique classes of 2'-5'-linked second messenger molecules, which - through distinct mechanisms - have crucial antiviral functions. 2'-5'-linked oligoadenylates limit viral propagation through the activation of the enzyme RNase L, which degrades host and viral RNA, and 2'-5'-linked cGAMP activates downstream signalling pathways to induce de novo antiviral gene expression. In this Progress article, we describe the striking functional and structural similarities between OAS proteins and cGAS, and highlight their roles in antiviral immunity.

  15. First evidence of Dinophysistoxin-1 ester and carcinogenic polycyclic aromatic hydrocarbons in smoked bivalves collected in the Patagonia fjords.

    PubMed

    García, Carlos; González, Viviana; Cornejo, Carlos; Palma-Fleming, Hernán; Lagos, Néstor

    2004-02-01

    Diarrhetic shellfish poisoning (DSP) is a gastrointestinal disease caused by fat-soluble polyether toxins produced by dinoflagellates and accumulated in shellfish. Up to the present, only four fat-soluble polyethers have been known as diarrhetic shellfish toxins. Among them,*** Okadaic acid, Dinophysistoxin-1, Dinophysistoxin-2 and Dinophysistoxin-3. Outbreaks associated with DSP have occurred in the Chilean Patagonia fjords since 1970. Native people, who live in small communities close to the southern fjords, smoke fresh shellfish. During this popular smoking procedure, they impregnate the shellfish with polycyclic aromatic hydrocarbons, as incomplete combustion products, which are potent carcinogenic compounds, this product is sold in local markets without phycotoxins analysis or inclusion in any monitoring program. The present paper shows, DSP phycotoxins quantitation, using high performance liquid chromatography with fluorescent and mass spectrometric detection and the measurements of polycyclic aromatic hydrocarbons by gas chromatography with mass detection, in smoked shellfish samples. The presence of Dinophysistoxin-3, the Dinophysistoxin-1 ester (7-O-acyl-derivatives of dinophysistoxin-1), was assessed in all shellfish samples analyzed. The 7-OH in Dinophysistoxin-1 was esterified with palmitic fatty acid. The shellfish meat contains seven polycyclic aromatic hydrocarbons, among them fluoranthene, phenanthrene, anthracene, pyrene and benzo[a]pyrene. The gas chromatography-mass spectrometry analysis showed four of the six most frequent carcinogenic polycyclic aromatic hydrocarbons reported. The content of benzo[a]pyrene in the Razor Clam and Ribbed Mussel were 78.61 and 4.94 ng/g of shellfish dry weight, respectively. In both cases the benzo[a]pyrene amounts were greater than the acceptable tolerance limits of 1 microg/kg of sample. The Razor Clam samples also show amount further above the maximum label regulated by FAO/WHO (10 microg/kg). The presence of

  16. Assessment of the hydrolysis process for the determination of okadaic acid-group toxin ester: presence of okadaic acid 7-O-acyl-ester derivates in Spanish shellfish.

    PubMed

    Villar-González, A; Rodríguez-Velasco, M L; Ben-Gigirey, B; Yasumoto, T; Botana, L M

    2008-04-01

    The contamination of different types of shellfish by okadaic acid (OA)-group toxin esters is an important problem that presents serious risk for human health. During previous investigations carried out in our laboratory by liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS), the occurrence of a high percentage of esters in relation to the total OA equivalents has been observed in several shellfish species. The determination of these kinds of toxins using LC/MS or other chemical methods requires a hydrolysis step in order to convert the sterified compounds into the parent toxins, OA, dinophysistoxins-1 (DTX-1) and dinophysistoxins-2 (DTX-2). Most of the hydrolysis procedures are based on an alkaline hydrolysis reaction. However, despite hydrolysis being a critical step within the analysis, it has not been studied in depth up to now. The present paper reports the results obtained after evaluating the hydrolysis process of an esterified form of OA by using a standard of 7-O-acyl ester with palmitoyl as the fatty acid (palOA). Investigations were focused on checking the effectiveness of the hydrolysis for palOA using methanol as solvent standard and matrices matched standards. From the results obtained, no matrix influence on the hydrolysis process was observed and the quantity of palOA converted into OA was always above 80%. The analyses of different Spanish shellfish samples showed percentages of palOA in relation to the total OA esters ranging from 27% to 90%, depending on the shellfish specie.

  17. Silverleaf Whitefly Induces Salicylic Acid Defenses and Suppresses Effectual Jasmonic Acid Defenses1[W][OA

    PubMed Central

    Zarate, Sonia I.; Kempema, Louisa A.; Walling, Linda L.

    2007-01-01

    The basal defenses important in curtailing the development of the phloem-feeding silverleaf whitefly (Bemisia tabaci type B; SLWF) on Arabidopsis (Arabidopsis thaliana) were investigated. Sentinel defense gene RNAs were monitored in SLWF-infested and control plants. Salicylic acid (SA)-responsive gene transcripts accumulated locally (PR1, BGL2, PR5, SID2, EDS5, PAD4) and systemically (PR1, BGL2, PR5) during SLWF nymph feeding. In contrast, jasmonic acid (JA)- and ethylene-dependent RNAs (PDF1.2, VSP1, HEL, THI2.1, FAD3, ERS1, ERF1) were repressed or not modulated in SLWF-infested leaves. To test for a role of SA and JA pathways in basal defense, SLWF development on mutant and transgenic lines that constitutively activate or impair defense pathways was determined. By monitoring the percentage of SLWF nymphs in each instar, we show that mutants that activate SA defenses (cim10) or impair JA defenses (coi1) accelerated SLWF nymphal development. Reciprocally, mutants that activate JA defenses (cev1) or impair SA defenses (npr1, NahG) slowed SLWF nymphal development. Furthermore, when npr1 plants, which do not activate downstream SA defenses, were treated with methyl jasmonate, a dramatic delay in nymph development was observed. Collectively, these results showed that SLWF-repressed, JA-regulated defenses were associated with basal defense to the SLWF. PMID:17189328

  18. Overlapping Patterns of Rapid Evolution in the Nucleic Acid Sensors cGAS and OAS1 Suggest a Common Mechanism of Pathogen Antagonism and Escape

    PubMed Central

    Hancks, Dustin C.; Hartley, Melissa K.; Hagan, Celia; Clark, Nathan L.; Elde, Nels C.

    2015-01-01

    A diverse subset of pattern recognition receptors (PRRs) detects pathogen-associated nucleic acids to initiate crucial innate immune responses in host organisms. Reflecting their importance for host defense, pathogens encode various countermeasures to evade or inhibit these immune effectors. PRRs directly engaged by pathogen inhibitors often evolve under recurrent bouts of positive selection that have been described as molecular ‘arms races.’ Cyclic GMP-AMP synthase (cGAS) was recently identified as a key PRR. Upon binding cytoplasmic double-stranded DNA (dsDNA) from various viruses, cGAS generates the small nucleotide secondary messenger cGAMP to signal activation of innate defenses. Here we report an evolutionary history of cGAS with recurrent positive selection in the primate lineage. Recent studies indicate a high degree of structural similarity between cGAS and 2’-5’-oligoadenylate synthase 1 (OAS1), a PRR that detects double-stranded RNA (dsRNA), despite low sequence identity between the respective genes. We present comprehensive comparative evolutionary analysis of cGAS and OAS1 primate sequences and observe positive selection at nucleic acid binding interfaces and distributed throughout both genes. Our data revealed homologous regions with strong signatures of positive selection, suggesting common mechanisms employed by unknown pathogen encoded inhibitors and similar modes of evasion from antagonism. Our analysis of cGAS diversification also identified alternately spliced forms missing multiple sites under positive selection. Further analysis of selection on the OAS family in primates, which comprises OAS1, OAS2, OAS3 and OASL, suggests a hypothesis where gene duplications and domain fusion events result in paralogs that provide another means of escaping pathogen inhibitors. Together our comparative evolutionary analysis of cGAS and OAS provides new insights into distinct mechanisms by which key molecular sentinels of the innate immune system have

  19. YAP and 14-3-3γ are involved in HS-OA-induced growth inhibition of hepatocellular carcinoma cells: A novel mechanism for hydrogen sulfide releasing oleanolic acid

    PubMed Central

    Xu, Guanglin; Wang, Jing; Wu, Fangfang; Wang, Na; Zhou, Wenli; Wang, Qian; Pan, Wang; Ao, Guizhen; Yang, Jiquan

    2016-01-01

    Hydrogen sulfide-releasing oleanolic acid (HS-OA) is an emerging novel class of compounds and consists of an oleanolic acid (OA) and a H2S-releasing moiety. Although it exhibits improved anti-inflammatory activity, its potency in human cancers has not been understood yet. In this study, we examined the effects of HS-OA on the growth of liver cancer cell lines and the underlying mechanisms. HS-OA inhibited the growth of all four cancer cell lines studied, with potencies of 10- to 30-fold greater than that of its counterpart (OA). HS-OA induced significant apoptosis and decreased viability, clonogenic activity and migration of Hep G2 cells. Further studies showed that HS-OA resulted in the reduction of YAP expression and its downstream targets, CTGF and CYR 61, thus promoting cell apoptosis. In addition, HS-OA caused a decrease of 14-3-3γ expression, which led to Bad translocation to the mitochondria, ΔΨm loss, cytochrome c release, caspase activation and a recovery of 14-3-3γ reversed these effects induced by HS-OA. These findings indicate that YAP and 14-3-3γ are involved in HS-OA's effects on liver cancer cells and identifying HS-OA as a potential new drug candidate for cancer therapy. PMID:27437776

  20. Diarrhetic effect of okadaic acid could be related with its neuronal action: Changes in neuropeptide Y.

    PubMed

    Louzao, M Carmen; Fernández, Diego A; Abal, Paula; Fraga, Maria; Vilariño, Natalia; Vieytes, Mercedes R; Botana, Luis M

    2015-09-02

    Okadaic acid (OA) and dinophysistoxins (DTXs) are a group of marine toxins that cause diarrheic shellfish poisoning (DSP) in humans and animals. These compounds are produced by dinoflagellates of the Prorocentrum and Dinophysis genera and can accumulate in filter-feeding bivalves, posing a serious health risk for shellfish consumers. The enteric nervous system (ENS) plays a crucial role in the regulation of the gastrointestinal tract. In addition, neuropeptides produced by ENS affects the epithelial barrier functions. In the present work we used a two-compartment human coculture model containing the SH-SY5Y neuroblastoma cell line and polarized colonic epithelial monolayers (Caco-2) to study the OA intestinal permeability. First, we have determined OA cytotoxicity and we have found that OA reduces the viability of SH-SY5Y in a dose-dependent way, even though DTX1 is 4 to 5 times more potent than OA. Besides DTX1 is 15 to 18 orders of magnitude more potent than OA in decreasing transepithelial electrical resistance (TEER) of caco-2 cells without inducing cytotoxicity. Permeability assays indicate that OA cross the monolayer and modulates the neuropeptide Y (NPY) secretion by neuroblastoma cells. This NPY also affects the permeability of OA. This offers a novel approach to establish the influence of OA neuronal action on their diarrheic effects through a cross talk between ENS and intestine via OA induced NPY secretion. Therefore, the OA mechanisms of toxicity that were long attributed only to the inhibition of protein phosphatases, would require a reevaluation.

  1. Abscisic Acid Mediates a Divergence in the Drought Response of Two Conifers1[W][OA

    PubMed Central

    Brodribb, Timothy J.; McAdam, Scott A.M.

    2013-01-01

    During water stress, stomatal closure occurs as water tension and levels of abscisic acid (ABA) increase in the leaf, but the interaction between these two drivers of stomatal aperture is poorly understood. We investigate the dynamics of water potential, ABA, and stomatal conductance during the imposition of water stress on two drought-tolerant conifer species with contrasting stomatal behavior. Rapid rehydration of excised shoots was used as a means of differentiating the direct influences of ABA and water potential on stomatal closure. Pinus radiata (Pinaceae) was found to exhibit ABA-driven stomatal closure during water stress, resulting in strongly isohydric regulation of water loss. By contrast, stomatal closure in Callitris rhomboidea (Cupressaceae) was initiated by elevated foliar ABA, but sustained water stress saw a marked decline in ABA levels and a shift to water potential-driven stomatal closure. The transition from ABA to water potential as the primary driver of stomatal aperture allowed C. rhomboidea to rapidly recover gas exchange after water-stressed plants were rewatered, and was associated with a strongly anisohydric regulation of water loss. These two contrasting mechanisms of stomatal regulation function in combination with xylem vulnerability to produce highly divergent strategies of water management. Species-specific ABA dynamics are proposed as a central component of drought survival and ecology. PMID:23709665

  2. A Nuclear Factor Regulates Abscisic Acid Responses in Arabidopsis1[W][OA

    PubMed Central

    Kim, Min Jung; Shin, Ryoung; Schachtman, Daniel P.

    2009-01-01

    Abscisic acid (ABA) is a plant hormone that regulates plant growth as well as stress responses. In this study, we identified and characterized a new Arabidopsis (Arabidopsis thaliana) protein, Nuclear Protein X1 (NPX1), which was up-regulated by stress and treatment with exogenous ABA. Stomatal closure, seed germination, and primary root growth are well-known ABA responses that were less sensitive to ABA in NPX1-overexpressing plants. NPX1-overexpressing plants were more drought sensitive, and the changes in response to drought were due to the altered guard cell sensitivity to ABA in transgenic plants and not to a lack of ABA production. The nuclear localization of NPX1 correlated with changes in the expression of genes involved in ABA biosynthesis and ABA signal transduction. To understand the function of NPX1, we searched for interacting proteins and found that an ABA-inducible NAC transcription factor, TIP, interacted with NPX1. Based on the whole plant phenotypes, we hypothesized that NPX1 acts as a transcriptional repressor, and this was demonstrated in yeast, where we showed that TIP was repressed by NPX1. Our results indicate that the previously unknown protein NPX1 acts as a negative regulator in plant response to changes in environmental conditions through the control of ABA-regulated gene expression. The characterization of this factor enhances our understanding of guard cell function and the mechanisms that plants use to modulate water loss from leaves under drought conditions. PMID:19759343

  3. Nickel Deficiency Disrupts Metabolism of Ureides, Amino Acids, and Organic Acids of Young Pecan Foliage[OA

    PubMed Central

    Bai, Cheng; Reilly, Charles C.; Wood, Bruce W.

    2006-01-01

    The existence of nickel (Ni) deficiency is becoming increasingly apparent in crops, especially for ureide-transporting woody perennials, but its physiological role is poorly understood. We evaluated the concentrations of ureides, amino acids, and organic acids in photosynthetic foliar tissue from Ni-sufficient (Ni-S) versus Ni-deficient (Ni-D) pecan (Carya illinoinensis [Wangenh.] K. Koch). Foliage of Ni-D pecan seedlings exhibited metabolic disruption of nitrogen metabolism via ureide catabolism, amino acid metabolism, and ornithine cycle intermediates. Disruption of ureide catabolism in Ni-D foliage resulted in accumulation of xanthine, allantoic acid, ureidoglycolate, and citrulline, but total ureides, urea concentration, and urease activity were reduced. Disruption of amino acid metabolism in Ni-D foliage resulted in accumulation of glycine, valine, isoleucine, tyrosine, tryptophan, arginine, and total free amino acids, and lower concentrations of histidine and glutamic acid. Ni deficiency also disrupted the citric acid cycle, the second stage of respiration, where Ni-D foliage contained very low levels of citrate compared to Ni-S foliage. Disruption of carbon metabolism was also via accumulation of lactic and oxalic acids. The results indicate that mouse-ear, a key morphological symptom, is likely linked to the toxic accumulation of oxalic and lactic acids in the rapidly growing tips and margins of leaflets. Our results support the role of Ni as an essential plant nutrient element. The magnitude of metabolic disruption exhibited in Ni-D pecan is evidence of the existence of unidentified physiological roles for Ni in pecan. PMID:16415214

  4. Effects of Glucosamine and Chondroitin Sulfate on Cartilage Metabolism in OA: Outlook on Other Nutrient Partners Especially Omega-3 Fatty Acids

    PubMed Central

    Jerosch, Jörg

    2011-01-01

    Osteoarthritis (OA) is a degenerative joint disease that is characterized by increasing loss of cartilage, remodeling of the periarticular bone, and inflammation of the synovial membrane. Besides the common OA therapy with nonsteroidal anti-inflammatory drugs (NSAIDs), the treatment with chondroprotectives, such as glucosamine sulfate, chondroitin sulfate, hyaluronic acid, collagen hydrolysate, or nutrients, such as antioxidants and omega-3 fatty acids is a promising therapeutic approach. Numerous clinical studies have demonstrated that the targeted administration of selected micronutrients leads to a more effective reduction of OA symptoms, with less adverse events. Their chondroprotective action can be explained by a dual mechanism: (1) as basic components of cartilage and synovial fluid, they stimulate the anabolic process of the cartilage metabolism; (2) their anti-inflammatory action can delay many inflammation-induced catabolic processes in the cartilage. These two mechanisms are able to slow the progression of cartilage destruction and may help to regenerate the joint structure, leading to reduced pain and increased mobility of the affected joint. PMID:21826146

  5. In vitro acylation of okadaic acid in the presence of various bivalves' extracts.

    PubMed

    Konoki, Keiichi; Onoda, Tatsuya; Watanabe, Ryuichi; Cho, Yuko; Kaga, Shinnosuke; Suzuki, Toshiyuki; Yotsu-Yamashita, Mari

    2013-01-29

    The dinoflagellate Dinophysis spp. is responsible for diarrhetic shellfish poisoning (DSP). In the bivalves exposed to the toxic bloom of the dinoflagellate, dinophysistoxin 3 (DTX3), the 7-OH acylated form of either okadaic acid (OA) or DTX1, is produced. We demonstrated in vitro acylation of OA with palmitoyl CoA in the presence of protein extract from the digestive gland, but not other tissues of the bivalve Mizuhopecten yessoensis. The yield of 7-O-palmitoyl OA reached its maximum within 2 h, was the highest at 37 °C followed by 28 °C, 16 °C and 4 °C and was the highest at pH 8 in comparison with the yields at pH 6 and pH 4. The transformation also proceeded when the protein extract was prepared from the bivalves Corbicula japonica and Crassostrea gigas. The OA binding protein OABP2 identified in the sponge Halichondria okadai was not detected in the bivalve M. yessoensis, the bivalve Mytilus galloprovincialis and the ascidian Halocynthia roretzi, though they are known to accumulate diarrhetic shellfish poisoning toxins. Since DTX3 does not bind to protein phosphatases 1 and 2A, the physiological target for OA and DTXs in mammalian cells, the acylation of DSP toxins would be related to a detoxification mechanism for the bivalve species.

  6. A hyaluronic acid-salmon calcitonin conjugate for the local treatment of osteoarthritis: chondro-protective effect in a rabbit model of early OA.

    PubMed

    Mero, Anna; Campisi, Monica; Favero, Marta; Barbera, Carlo; Secchieri, Cynthia; Dayer, Jean M; Goldring, Mary B; Goldring, Steven R; Pasut, Gianfranco

    2014-08-10

    Osteoarthritis (OA) is characterized by chronic degeneration of joints, involving mainly the articular cartilage and the underlying bone, and severely impairing the quality of life of the patient. Although with limited efficacy, currently available pharmacological treatments for OA aim to control pain and to retard disease progression. Salmon calcitonin (sCT) is a drug which has been shown to have therapeutic effects in experimental arthritis by inhibiting both bone turnover and cartilage degradation and reducing the activities of matrix metalloproteinases (MMP). High molecular weight hyaluronic acid (HA) is used as a lubricant in OA therapy, and, interestingly, HA polymers may normalize the levels of MMP-1, -3 and -13. We demonstrated that sCT rapidly clears from the knee joint of rat animal model, after intra-articular (i.a.) administration, and it induces systemic effects. Here, sCT was conjugated to HA (200kDa) with the aim of prolonging the residence time of the polypeptide in the joint space by reducing its clearance. An aldehyde derivative of HA was used for N-terminal site-selective coupling of sCT. The activity of sCT was preserved, both in vitro and in vivo, after its conjugation and the i.a. injection of HA-sCT did not trigger any systemic effects in rats. The efficacy of HA-sCT treatment was tested in a rabbit OA model and clear chondro-protective effect was proven by macro- and microscopic assessments and histological findings. Our results indicate that HAylation of sCT increases the size of the polypeptide in a stable covalent manner and delays its passage into the blood stream. We conclude that HA conjugation prolongs the anti-catabolic effects of sCT in joint tissues, including the synovial membrane and cartilage.

  7. The Phosphatidylcholine Diacylglycerol Cholinephosphotransferase Is Required for Efficient Hydroxy Fatty Acid Accumulation in Transgenic Arabidopsis1[W][OA

    PubMed Central

    Hu, Zhaohui; Ren, Zhonghai; Lu, Chaofu

    2012-01-01

    We previously identified an enzyme, phosphatidylcholine diacylglycerol cholinephosphotransferase (PDCT), that plays an important role in directing fatty acyl fluxes during triacylglycerol (TAG) biosynthesis. The PDCT mediates a symmetrical interconversion between phosphatidylcholine (PC) and diacylglycerol (DAG), thus enriching PC-modified fatty acids in the DAG pool prior to forming TAG. We show here that PDCT is required for the efficient metabolism of engineered hydroxy fatty acids in Arabidopsis (Arabidopsis thaliana) seeds. When a fatty acid hydroxylase (FAH12) from castor (Ricinus communis) was expressed in Arabidopsis seeds, the PDCT-deficient mutant accumulated only about half the amount of hydroxy fatty acids compared with that in the wild-type seeds. We also isolated a PDCT from castor encoded by the RcROD1 (Reduced Oleate Desaturation1) gene. Seed-specific coexpression of this enzyme significantly increased hydroxy fatty acid accumulation in wild type-FAH12 and in a previously produced transgenic Arabidopsis line coexpressing a castor diacylglycerol acyltransferase 2. Analyzing the TAG molecular species and regiochemistry, along with analysis of fatty acid composition in TAG and PC during seed development, indicate that PDCT acts in planta to enhance the fluxes of fatty acids through PC and enrich the hydroxy fatty acids in DAG, and thus in TAG. In addition, PDCT partially restores the oil content that is decreased in FAH12-expressing seeds. Our results add a new gene in the genetic toolbox for efficiently engineering unusual fatty acids in transgenic oilseeds. PMID:22371508

  8. New esters of okadaic acid in seawater and blue mussels (Mytilus edulis).

    PubMed

    Torgersen, Trine; Miles, Christopher O; Rundberget, Thomas; Wilkins, Alistair L

    2008-10-22

    Marine algal toxins of the okadaic acid (OA) group can occur as diol esters and sulfated diol esters in algae and as fatty acid esters in shellfish. Several of these ester forms have been identified, but the most common procedure for detecting OA group toxin esters is by measuring the increase in parent toxin after alkaline hydrolysis. Use of this alkaline hydrolysis method led to the discovery of high levels of conjugates of OA and dinophysistoxins-2 (DTX2) in seawater and of OA, DTX1, and DTX2 in blue mussel hepatopancreas (HP) from Flødevigen, Norway, during a bloom of Dinophysis spp. In the water sample, a C 8-diol ester, a C 9-diol ester, and a previously undescribed C 8-triol ester of OA were characterized using HPLC-MS (2), -MS (3), and -MS (4) in combination with various derivatization procedures. Palmitic acid (16:0) ester derivatives of these diol/triol esters were found in mussel HP and characterized using HPLC-MS (2), -MS (3), and -MS (4). To the authors' knowledge, hybrid diol-fatty acid esters of OA have not been previously described. Mass spectral analysis showed the presence of two forms of hybrid esters: one with the fatty acid conjugated to the 7-OH of the OA moiety and the other with the fatty acid conjugated to the OH group in the "diol" moiety. In the water sample, the C 8-diol ester was the most abundant, whereas in the mussels, the 16:0-C 9-diol hybrid ester was most abundant, and only minor amounts of the 16:0-C 8-diol hybrid ester were detected, suggesting that C 8- and C 9-diol esters of OA may be metabolized differently in blue mussels. 7- O-acyl esters of OA, DTX1, and DTX2 are thought to contribute to shellfish toxicity by being hydrolyzed in the human stomach to the parent toxins, and the newly characterized hybrid esters are likely to contribute similarly.

  9. From Amino Acid to Glucosinolate Biosynthesis: Protein Sequence Changes in the Evolution of Methylthioalkylmalate Synthase in Arabidopsis[W][OA

    PubMed Central

    de Kraker, Jan-Willem; Gershenzon, Jonathan

    2011-01-01

    Methylthioalkylmalate synthase (MAM) catalyzes the committed step in the side chain elongation of Met, yielding important precursors for glucosinolate biosynthesis in Arabidopsis thaliana and other Brassicaceae species. MAM is believed to have evolved from isopropylmalate synthase (IPMS), an enzyme involved in Leu biosynthesis, based on phylogenetic analyses and an overlap of catalytic abilities. Here, we investigated the changes in protein structure that have occurred during the recruitment of IPMS from amino acid to glucosinolate metabolism. The major sequence difference between IPMS and MAM is the absence of 120 amino acids at the C-terminal end of MAM that constitute a regulatory domain for Leu-mediated feedback inhibition. Truncation of this domain in Arabidopsis IPMS2 results in loss of Leu feedback inhibition and quaternary structure, two features common to MAM enzymes, plus an 8.4-fold increase in the kcat/Km for a MAM substrate. Additional exchange of two amino acids in the active site resulted in a MAM-like enzyme that had little residual IPMS activity. Hence, combination of the loss of the regulatory domain and a few additional amino acid exchanges can explain the evolution of MAM from IPMS during its recruitment from primary to secondary metabolism. PMID:21205930

  10. The Tryptophan Conjugates of Jasmonic and Indole-3-Acetic Acids Are Endogenous Auxin Inhibitors1[W][OA

    PubMed Central

    Staswick, Paul E.

    2009-01-01

    Most conjugates of plant hormones are inactive, and some function to reduce the active hormone pool. This study characterized the activity of the tryptophan (Trp) conjugate of jasmonic acid (JA-Trp) in Arabidopsis (Arabidopsis thaliana). Unexpectedly, JA-Trp caused agravitropic root growth in seedlings, unlike JA or nine other JA-amino acid conjugates. The response was dose dependent from 1 to100 μm, was independent of the COI1 jasmonate signaling locus, and unlike the jasmonate signal JA-isoleucine, JA-Trp minimally inhibited root growth. The Trp conjugate with indole-3-acetic acid (IAA-Trp) produced a similar response, while Trp alone and conjugates with benzoic and cinnamic acids did not. JA-Trp and IAA-Trp at 25 μm nearly eliminated seedling root inhibition caused by 2 μm IAA. The TIR1 auxin receptor is required for activity because roots of tir1-1 grew only approximately 60% of wild-type length on IAA plus JA-Trp, even though tir1-1 is auxin resistant. However, neither JA-Trp nor IAA-Trp interfered with IAA-dependent interaction between TIR1 and Aux/IAA7 in cell-free assays. Trp conjugates inhibited IAA-stimulated lateral root production and DR5-β-glucuronidase gene expression. JA-deficient mutants were hypersensitive to IAA and a Trp-overaccumulating mutant was less sensitive, suggesting endogenous conjugates affect auxin sensitivity. Conjugates were present at 5.8 pmol g−1 fresh weight or less in roots, seedlings, leaves, and flowers, and the values increased approximately 10-fold in roots incubated in 25 μm Trp and IAA or JA at 2 μm. These results show that JA-Trp and IAA-Trp constitute a previously unrecognized mechanism to regulate auxin action. PMID:19458116

  11. Characterization of the Branched-Chain Amino Acid Aminotransferase Enzyme Family in Tomato1[W][OA

    PubMed Central

    Maloney, Gregory S.; Kochevenko, Andrej; Tieman, Denise M.; Tohge, Takayuki; Krieger, Uri; Zamir, Dani; Taylor, Mark G.; Fernie, Alisdair R.; Klee, Harry J.

    2010-01-01

    Branched-chain amino acids (BCAAs) are synthesized in plants from branched-chain keto acids, but their metabolism is not completely understood. The interface of BCAA metabolism lies with branched-chain aminotransferases (BCAT) that catalyze both the last anabolic step and the first catabolic step. In this study, six BCAT genes from the cultivated tomato (Solanum lycopersicum) were identified and characterized. SlBCAT1, -2, -3, and -4 are expressed in multiple plant tissues, while SlBCAT5 and -6 were undetectable. SlBCAT1 and -2 are located in the mitochondria, SlBCAT3 and -4 are located in chloroplasts, while SlBCAT5 and -6 are located in the cytosol and vacuole, respectively. SlBCAT1, -2, -3, and -4 were able to restore growth of Escherichia coli BCAA auxotrophic cells, but SlBCAT1 and -2 were less effective than SlBCAT3 and -4 in growth restoration. All enzymes were active in the forward (BCAA synthesis) and reverse (branched-chain keto acid synthesis) reactions. SlBCAT3 and -4 exhibited a preference for the forward reaction, while SlBCAT1 and -2 were more active in the reverse reaction. While overexpression of SlBCAT1 or -3 in tomato fruit did not significantly alter amino acid levels, an expression quantitative trait locus on chromosome 3, associated with substantially higher expression of Solanum pennellii BCAT4, did significantly increase BCAA levels. Conversely, antisense-mediated reduction of SlBCAT1 resulted in higher levels of BCAAs. Together, these results support a model in which the mitochondrial SlBCAT1 and -2 function in BCAA catabolism while the chloroplastic SlBCAT3 and -4 function in BCAA synthesis. PMID:20435740

  12. Castor Phospholipid:Diacylglycerol Acyltransferase Facilitates Efficient Metabolism of Hydroxy Fatty Acids in Transgenic Arabidopsis1[W][OA

    PubMed Central

    van Erp, Harrie; Bates, Philip D.; Burgal, Julie; Shockey, Jay; Browse, John

    2011-01-01

    Producing unusual fatty acids (FAs) in crop plants has been a long-standing goal of green chemistry. However, expression of the enzymes that catalyze the primary synthesis of these unusual FAs in transgenic plants typically results in low levels of the desired FA. For example, seed-specific expression of castor (Ricinus communis) fatty acid hydroxylase (RcFAH) in Arabidopsis (Arabidopsis thaliana) resulted in only 17% hydroxy fatty acids (HFAs) in the seed oil. In order to increase HFA levels, we investigated castor phospholipid:diacylglycerol acyltransferase (PDAT). We cloned cDNAs encoding three putative PDAT enzymes from a castor seed cDNA library and coexpressed them with RcFAH12. One isoform, RcPDAT1A, increased HFA levels to 27%. Analysis of HFA-triacylglycerol molecular species and regiochemistry, along with analysis of the HFA content of phosphatidylcholine, indicates that RcPDAT1A functions as a PDAT in vivo. Expression of RcFAH12 alone leads to a significant decrease in FA content of seeds. Coexpression of RcPDAT1A and RcDGAT2 (for diacylglycerol acyltransferase 2) with RcFAH12 restored FA levels to nearly wild-type levels, and this was accompanied by a major increase in the mass of HFAs accumulating in the seeds. We show the usefulness of RcPDAT1A for engineering plants with high levels of HFAs and alleviating bottlenecks due to the production of unusual FAs in transgenic oilseeds. PMID:21173026

  13. Tricarboxylic Acid Cycle Activity Regulates Tomato Root Growth via Effects on Secondary Cell Wall Production1[W][OA

    PubMed Central

    van der Merwe, Margaretha J.; Osorio, Sonia; Araújo, Wagner L.; Balbo, Ilse; Nunes-Nesi, Adriano; Maximova, Eugenia; Carrari, Fernando; Bunik, Victoria I.; Persson, Staffan; Fernie, Alisdair R.

    2010-01-01

    Transgenic tomato (Solanum lycopersicum ‘Moneymaker’) plants independently expressing fragments of various genes encoding enzymes of the tricarboxylic acid cycle in antisense orientation have previously been characterized as exhibiting altered root growth. In this study, we evaluate the rates of respiration of roots from these lines in addition to determining their total dry weight accumulation. Given that these features were highly correlated, we decided to carry out an evaluation of the cell wall composition in the transformants that revealed a substantial reduction in cellulose. Since the bulk of cellulose is associated with the secondary cell walls in roots, we reasoned that the transformants most likely were deficient in secondary wall cellulose production. Consistent with these findings, cross-sections of the root collar (approximately 15 mm from the junction between root and stem) displayed reduced lignified secondary cell walls for the transformants. In contrast, cell and cell wall patterning displayed no differences in elongating cells close to the root tip. To further characterize the modified cell wall metabolism, we performed feeding experiments in which we incubated excised root tips in [U-14C]glucose in the presence or absence of phosphonate inhibitors of the reaction catalyzed by 2-oxoglutarate dehydrogenase. Taken together, the combined results suggest that restriction of root respiration leads to a deficit in secondary cell wall synthesis. These data are discussed in the context of current models of biomass partitioning and plant growth. PMID:20118274

  14. Sequencing around 5-Hydroxyconiferyl Alcohol-Derived Units in Caffeic Acid O-Methyltransferase-Deficient Poplar Lignins1[OA

    PubMed Central

    Lu, Fachuang; Marita, Jane M.; Lapierre, Catherine; Jouanin, Lise; Morreel, Kris; Boerjan, Wout; Ralph, John

    2010-01-01

    Caffeic acid O-methyltransferase (COMT) is a bifunctional enzyme that methylates the 5- and 3-hydroxyl positions on the aromatic ring of monolignol precursors, with a preference for 5-hydroxyconiferaldehyde, on the way to producing sinapyl alcohol. Lignins in COMT-deficient plants contain benzodioxane substructures due to the incorporation of 5-hydroxyconiferyl alcohol (5-OH-CA), as a monomer, into the lignin polymer. The derivatization followed by reductive cleavage method can be used to detect and determine benzodioxane structures because of their total survival under this degradation method. Moreover, partial sequencing information for 5-OH-CA incorporation into lignin can be derived from detection or isolation and structural analysis of the resulting benzodioxane products. Results from a modified derivatization followed by reductive cleavage analysis of COMT-deficient lignins provide evidence that 5-OH-CA cross couples (at its β-position) with syringyl and guaiacyl units (at their O-4-positions) in the growing lignin polymer and then either coniferyl or sinapyl alcohol, or another 5-hydroxyconiferyl monomer, adds to the resulting 5-hydroxyguaiacyl terminus, producing the benzodioxane. This new terminus may also become etherified by coupling with further monolignols, incorporating the 5-OH-CA integrally into the lignin structure. PMID:20427467

  15. Overproduction of Abscisic Acid in Tomato Increases Transpiration Efficiency and Root Hydraulic Conductivity and Influences Leaf Expansion1[OA

    PubMed Central

    Thompson, Andrew J.; Andrews, John; Mulholland, Barry J.; McKee, John M.T.; Hilton, Howard W.; Horridge, Jon S.; Farquhar, Graham D.; Smeeton, Rachel C.; Smillie, Ian R.A.; Black, Colin R.; Taylor, Ian B.

    2007-01-01

    Overexpression of genes that respond to drought stress is a seemingly attractive approach for improving drought resistance in crops. However, the consequences for both water-use efficiency and productivity must be considered if agronomic utility is sought. Here, we characterize two tomato (Solanum lycopersicum) lines (sp12 and sp5) that overexpress a gene encoding 9-cis-epoxycarotenoid dioxygenase, the enzyme that catalyzes a key rate-limiting step in abscisic acid (ABA) biosynthesis. Both lines contained more ABA than the wild type, with sp5 accumulating more than sp12. Both had higher transpiration efficiency because of their lower stomatal conductance, as demonstrated by increases in δ13C and δ18O, and also by gravimetric and gas-exchange methods. They also had greater root hydraulic conductivity. Under well-watered glasshouse conditions, mature sp5 plants were found to have a shoot biomass equal to the wild type despite their lower assimilation rate per unit leaf area. These plants also had longer petioles, larger leaf area, increased specific leaf area, and reduced leaf epinasty. When exposed to root-zone water deficits, line sp12 showed an increase in xylem ABA concentration and a reduction in stomatal conductance to the same final levels as the wild type, but from a different basal level. Indeed, the main difference between the high ABA plants and the wild type was their performance under well-watered conditions: the former conserved soil water by limiting maximum stomatal conductance per unit leaf area, but also, at least in the case of sp5, developed a canopy more suited to light interception, maximizing assimilation per plant, possibly due to improved turgor or suppression of epinasty. PMID:17277097

  16. Characterization of the dinophysistoxin-2 acute oral toxicity in mice to define the Toxicity Equivalency Factor.

    PubMed

    Abal, Paula; Louzao, M Carmen; Cifuentes, José Manuel; Vilariño, Natalia; Rodriguez, Ines; Alfonso, Amparo; Vieytes, Mercedes R; Botana, Luis M

    2017-04-01

    Ingestion of shellfish with dinophysistoxin-2 (DTX2) can lead to diarrheic shellfish poisoning (DSP). The official control method of DSP toxins in seafood is the liquid chromatography-mass spectrometry analysis (LC-MS). However in order to calculate the total toxicity of shellfish, the concentration of each compound must be multiplied by individual Toxicity Equivalency Factor (TEF). Considering that TEFs caused some controversy and the scarce information about DTX2 toxicity, the aim of this study was to characterize the oral toxicity of DTX2 in mice. A 4-Level Up and Down Procedure allowed the characterization of DTX2 effects and the estimation of DTX2 oral TEF based on determination of the lethal dose 50 (LD50). DTX2 passed the gastrointestinal barrier and was detected in urine and feces. Acute toxicity symptoms include diarrhea and motionless, however anatomopathology study and ultrastructural images restricted the toxin effects to the gastrointestinal tract. Nevertheless enterocytes microvilli and tight junctions were not altered, disconnecting DTX2 diarrheic effects from paracellular epithelial permeability. This is the first report of DTX2 oral LD50 (2262 μg/kg BW) indicating that its TEF is about 0.4. This result suggests reevaluation of the present TEFs for the DSP toxins to better determine the actual risk to seafood consumers.

  17. Douglas OA-4A Dolphin

    NASA Technical Reports Server (NTRS)

    1938-01-01

    Douglas OA-4A Dolphin: This twin-engine Douglas OA-4A Dolphin was unusual in comparison with other OA-4s in that it employed a nose wheel instead of a tail wheel during its NACA testing at Langley. Here is is seen in the NACA hangar in September 1938.

  18. Influence of OAS-1000 on mediators of inflammation.

    PubMed

    Scherl, D S; Afflitto, J; Gaffar, A

    1999-04-01

    OAS-1000 is a semisynthetic derivative of pseudopterosine A, isolated from sea whip (Pseudopterogorgia elizabethae), that has been shown to have topical anti-inflammatory activity. The purpose of this research was to investigate OAS-1000 for potential use as an anti-inflammatory agent for topical oral application, and to begin to investigate a mechanism of action. OAS-1000 was therefore evaluated as an inhibitor of 4 enzymes of the arachidonic acid metabolic pathways (prostaglandin G/H synthase I (PGHS-1, COX-1), prostaglandin G/H synthase II (PGHS-2, COX-2), arachidonate 5-lipoxygenase (5-LOX), and arachidonate 15-lipoxygenase (15-LOX)). It was found that OAS-1000 inhibits PGHS-1 activity with an IC-50 value of 80.3 microM, but had much less activity versus PGHS-2 enzyme and no activity versus the 15-LOX enzyme. 5-LOX activity showed some inhibition, but only at a high OAS-1000 concentrations. Additionally, OAS-1000 was tested for it's ability inhibit 1 ng/ml IL-1beta stimulated PGE2 production in a cell culture system. Inhibition of 46% was seen at an OAS-1000 concentration of 22.4 microM. Taken together, these experiments suggest that at least some of the topical anti-inflammatory activity of OAS-1000 may be attributed to inhibition of the arachidonic acid metabolites that have been shown to be important in inflammation and tissue destruction.

  19. The Magnesium-Chelatase H Subunit Binds Abscisic Acid and Functions in Abscisic Acid Signaling: New Evidence in Arabidopsis1[W][OA

    PubMed Central

    Wu, Fu-Qing; Xin, Qi; Cao, Zheng; Liu, Zhi-Qiang; Du, Shu-Yuan; Mei, Chao; Zhao, Chen-Xi; Wang, Xiao-Fang; Shang, Yi; Jiang, Tao; Zhang, Xiao-Feng; Yan, Lu; Zhao, Rui; Cui, Zi-Ning; Liu, Rui; Sun, Hai-Li; Yang, Xin-Ling; Su, Zhen; Zhang, Da-Peng

    2009-01-01

    Using a newly developed abscisic acid (ABA)-affinity chromatography technique, we showed that the magnesium-chelatase H subunit ABAR/CHLH (for putative abscisic acid receptor/chelatase H subunit) specifically binds ABA through the C-terminal half but not the N-terminal half. A set of potential agonists/antagonists to ABA, including 2-trans,4-trans-ABA, gibberellin, cytokinin-like regulator 6-benzylaminopurine, auxin indole-3-acetic acid, auxin-like substance naphthalene acetic acid, and jasmonic acid methyl ester, did not bind ABAR/CHLH. A C-terminal C370 truncated ABAR with 369 amino acid residues (631–999) was shown to bind ABA, which may be a core of the ABA-binding domain in the C-terminal half. Consistently, expression of the ABAR/CHLH C-terminal half truncated proteins fused with green fluorescent protein (GFP) in wild-type plants conferred ABA hypersensitivity in all major ABA responses, including seed germination, postgermination growth, and stomatal movement, and the expression of the same truncated proteins fused with GFP in an ABA-insensitive cch mutant of the ABAR/CHLH gene restored the ABA sensitivity of the mutant in all of the ABA responses. However, the effect of expression of the ABAR N-terminal half fused with GFP in the wild-type plants was limited to seedling growth, and the restoring effect of the ABA sensitivity of the cch mutant was limited to seed germination. In addition, we identified two new mutant alleles of ABAR/CHLH from the mutant pool in the Arabidopsis Biological Resource Center via Arabidopsis (Arabidopsis thaliana) Targeting-Induced Local Lesions in Genomes. The abar-2 mutant has a point mutation resulting in the N-terminal Leu-348→Phe, and the abar-3 mutant has a point mutation resulting in the N-terminal Ser-183→Phe. The two mutants show altered ABA-related phenotypes in seed germination and postgermination growth but not in stomatal movement. These findings support the idea that ABAR/CHLH is an ABA receptor and reveal

  20. Salicylic Acid Suppresses Jasmonic Acid Signaling Downstream of SCFCOI1-JAZ by Targeting GCC Promoter Motifs via Transcription Factor ORA59[C][W][OA

    PubMed Central

    Van der Does, Dieuwertje; Leon-Reyes, Antonio; Koornneef, Annemart; Van Verk, Marcel C.; Rodenburg, Nicole; Pauwels, Laurens; Goossens, Alain; Körbes, Ana P.; Memelink, Johan; Ritsema, Tita; Van Wees, Saskia C.M.; Pieterse, Corné M.J.

    2013-01-01

    Antagonism between the defense hormones salicylic acid (SA) and jasmonic acid (JA) plays a central role in the modulation of the plant immune signaling network, but the molecular mechanisms underlying this phenomenon are largely unknown. Here, we demonstrate that suppression of the JA pathway by SA functions downstream of the E3 ubiquitin-ligase Skip-Cullin-F-box complex SCFCOI1, which targets JASMONATE ZIM-domain transcriptional repressor proteins (JAZs) for proteasome-mediated degradation. In addition, neither the stability nor the JA-induced degradation of JAZs was affected by SA. In silico promoter analysis of the SA/JA crosstalk transcriptome revealed that the 1-kb promoter regions of JA-responsive genes that are suppressed by SA are significantly enriched in the JA-responsive GCC-box motifs. Using GCC:GUS lines carrying four copies of the GCC-box fused to the β-glucuronidase reporter gene, we showed that the GCC-box motif is sufficient for SA-mediated suppression of JA-responsive gene expression. Using plants overexpressing the GCC-box binding APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factors ERF1 or ORA59, we found that SA strongly reduces the accumulation of ORA59 but not that of ERF1. Collectively, these data indicate that the SA pathway inhibits JA signaling downstream of the SCFCOI1-JAZ complex by targeting GCC-box motifs in JA-responsive promoters via a negative effect on the transcriptional activator ORA59. PMID:23435661

  1. High abundances of oxalic, azelaic, and glyoxylic acids and methylglyoxal in the open ocean with high biological activity: Implication for secondary OA formation from isoprene

    NASA Astrophysics Data System (ADS)

    Bikkina, Srinivas; Kawamura, Kimitaka; Miyazaki, Yuzo; Fu, Pingqing

    2014-05-01

    Atmospheric dicarboxylic acids (DCA) are a ubiquitous water-soluble component of secondary organic aerosols (SOA), which can act as cloud condensation nuclei (CCN), affecting the Earth's climate. Despite the high abundances of oxalic acid and related compounds in the marine aerosols, there is no consensus on what controls their distributions over the open ocean. Marine biological productivity could play a role in the production of DCA, but there is no substantial evidence to support this hypothesis. Here we present latitudinal distributions of DCA, oxoacids and α-dicarbonyls in the marine aerosols from the remote Pacific. Their concentrations were found several times higher in more biologically influenced aerosols (MBA) than less biologically influenced aerosols. We propose isoprene and unsaturated fatty acids as sources of DCA as inferred from significantly higher abundances of isoprene-SOA tracers and azelaic acid in MBA. These results have implications toward the reassessment of climate forcing feedbacks of marine-derived SOA.

  2. The Acyl-Acyl Carrier Protein Synthetase from Synechocystis sp. PCC 6803 Mediates Fatty Acid Import1[C][W][OA

    PubMed Central

    von Berlepsch, Simon; Kunz, Hans-Henning; Brodesser, Susanne; Fink, Patrick; Marin, Kay; Flügge, Ulf-Ingo; Gierth, Markus

    2012-01-01

    The transfer of fatty acids across biological membranes is a largely uncharacterized process, although it is essential at membranes of several higher plant organelles like chloroplasts, peroxisomes, or the endoplasmic reticulum. Here, we analyzed loss-of-function mutants of the unicellular cyanobacterium Synechocystis sp. PCC 6803 as a model system to circumvent redundancy problems encountered in eukaryotic organisms. Cells deficient in the only cytoplasmic Synechocystis acyl-acyl carrier protein synthetase (SynAas) were highly resistant to externally provided α-linolenic acid, whereas wild-type cells bleached upon this treatment. Bleaching of wild-type cells was accompanied by a continuous increase of α-linolenic acid in total lipids, whereas no such accumulation could be observed in SynAas-deficient cells (Δsynaas). When SynAas was disrupted in the tocopherol-deficient, α-linolenic acid-hypersensitive Synechocystis mutant Δslr1736, double mutant cells displayed the same resistance phenotype as Δsynaas. Moreover, heterologous expression of SynAas in yeast (Saccharomyces cerevisiae) mutants lacking the major yeast fatty acid import protein Fat1p (Δfat1) led to the restoration of wild-type sensitivity against exogenous α-linolenic acid of the otherwise resistant Δfat1 mutant, indicating that SynAas is functionally equivalent to Fat1p. In addition, liposome assays provided direct evidence for the ability of purified SynAas protein to mediate α-[14C]linolenic acid retrieval from preloaded liposome membranes via the synthesis of [14C]linolenoyl-acyl carrier protein. Taken together, our data show that an acyl-activating enzyme like SynAas is necessary and sufficient to mediate the transfer of fatty acids across a biological membrane. PMID:22535424

  3. Turnover of Fatty Acids during Natural Senescence of Arabidopsis, Brachypodium, and Switchgrass and in Arabidopsis β-Oxidation Mutants1[C][W][OA

    PubMed Central

    Yang, Zhenle; Ohlrogge, John B.

    2009-01-01

    During leaf senescence, macromolecule breakdown occurs and nutrients are translocated to support growth of new vegetative tissues, seeds, or other storage organs. In this study, we determined the fatty acid levels and profiles in Arabidopsis (Arabidopsis thaliana), Brachypodium distachyon, and switchgrass (Panicum virgatum) leaves during natural senescence. In young leaves, fatty acids represent 4% to 5% of dry weight and approximately 10% of the chemical energy content of the leaf tissues. In all three species, fatty acid levels in leaves began to decline at the onset of leaf senescence and progressively decreased as senescence advanced, resulting in a greater than 80% decline in fatty acids on a dry weight basis. During senescence, Arabidopsis leaves lost 1.6% of fatty acids per day at a rate of 2.1 μg per leaf (0.6 μg mg−1 dry weight). Triacylglycerol levels remained less than 1% of total lipids at all stages. In contrast to glycerolipids, aliphatic surface waxes of Arabidopsis leaves were much more stable, showing only minor reduction during senescence. We also examined three Arabidopsis mutants, acx1acx2, lacs6lacs7, and kat2, which are blocked in enzyme activities of β-oxidation and are defective in lipid mobilization during seed germination. In each case, no major differences in the fatty acid contents of leaves were observed between these mutants and the wild type, indicating that several mutations in β-oxidation that cause reduced breakdown of reserve oil in seeds do not substantially reduce the degradation of fatty acids during leaf senescence. PMID:19561121

  4. Arabidopsis Deficient in Cutin Ferulate Encodes a Transferase Required for Feruloylation of ω-Hydroxy Fatty Acids in Cutin Polyester1[W][OA

    PubMed Central

    Rautengarten, Carsten; Ebert, Berit; Ouellet, Mario; Nafisi, Majse; Baidoo, Edward E.K.; Benke, Peter; Stranne, Maria; Mukhopadhyay, Aindrila; Keasling, Jay D.; Sakuragi, Yumiko; Scheller, Henrik Vibe

    2012-01-01

    The cuticle is a complex aliphatic polymeric layer connected to the cell wall and covers surfaces of all aerial plant organs. The cuticle prevents nonstomatal water loss, regulates gas exchange, and acts as a barrier against pathogen infection. The cuticle is synthesized by epidermal cells and predominantly consists of an aliphatic polymer matrix (cutin) and intracuticular and epicuticular waxes. Cutin monomers are primarily C16 and C18 unsubstituted, ω-hydroxy, and α,ω-dicarboxylic fatty acids. Phenolics such as ferulate and p-coumarate esters also contribute to a minor extent to the cutin polymer. Here, we present the characterization of a novel acyl-coenzyme A (CoA)-dependent acyl-transferase that is encoded by a gene designated Deficient in Cutin Ferulate (DCF). The DCF protein is responsible for the feruloylation of ω-hydroxy fatty acids incorporated into the cutin polymer of aerial Arabidopsis (Arabidopsis thaliana) organs. The enzyme specifically transfers hydroxycinnamic acids using ω-hydroxy fatty acids as acyl acceptors and hydroxycinnamoyl-CoAs, preferentially feruloyl-CoA and sinapoyl-CoA, as acyl donors in vitro. Arabidopsis mutant lines carrying DCF loss-of-function alleles are devoid of rosette leaf cutin ferulate and exhibit a 50% reduction in ferulic acid content in stem insoluble residues. DCF is specifically expressed in the epidermis throughout all green Arabidopsis organs. The DCF protein localizes to the cytosol, suggesting that the feruloylation of cutin monomers takes place in the cytoplasm. PMID:22158675

  5. Development of OA Abroad and Its Inspirations

    ERIC Educational Resources Information Center

    Bi, Jing

    2010-01-01

    This study introduces the concept and characteristics of open access (OA), analyses the status quo and development of OA in foreign countries, and discusses its inspiration to its future development in China.

  6. The Synthetic Elicitor 3,5-Dichloroanthranilic Acid Induces NPR1-Dependent and NPR1-Independent Mechanisms of Disease Resistance in Arabidopsis1[W][OA

    PubMed Central

    Knoth, Colleen; Salus, Melinda S.; Girke, Thomas; Eulgem, Thomas

    2009-01-01

    Immune responses of Arabidopsis (Arabidopsis thaliana) are at least partially mediated by coordinated transcriptional up-regulation of plant defense genes, such as the Late/sustained Up-regulation in Response to Hyaloperonospora parasitica (LURP) cluster. We found a defined region in the promoter of the LURP member CaBP22 to be important for this response. Using a CaBP22 promoter-reporter fusion, we have established a robust and specific high-throughput screening system for synthetic defense elicitors that can be used to trigger defined subsets of plant immune responses. Screening a collection of 42,000 diversity-oriented molecules, we identified 114 candidate LURP inducers. One representative, 3,5-dichloroanthranilic acid (DCA), efficiently induced defense reactions to the phytopathogens H. parasitica and Pseudomonas syringae. In contrast to known salicylic acid analogs, such as 2,6-dichloroisonicotinic acid (INA), which exhibit a long-lasting defense-inducing activity and are fully dependent on the transcriptional cofactor NPR1 (for Nonexpresser of Pathogenesis-Related genes1), DCA acts transiently and is only partially dependent on NPR1. Microarray analyses revealed a cluster of 142 DCA- and INA-responsive genes that show a pattern of differential expression coinciding with the kinetics of DCA-mediated disease resistance. These ACID genes (for Associated with Chemically Induced Defense) constitute a core gene set associated with chemically induced disease resistance, many of which appear to encode components of the natural immune system of Arabidopsis. PMID:19304930

  7. Comparative Transcriptome Analysis of Three Oil Palm Fruit and Seed Tissues That Differ in Oil Content and Fatty Acid Composition1[C][W][OA

    PubMed Central

    Dussert, Stéphane; Guerin, Chloé; Andersson, Mariette; Joët, Thierry; Tranbarger, Timothy J.; Pizot, Maxime; Sarah, Gautier; Omore, Alphonse; Durand-Gasselin, Tristan; Morcillo, Fabienne

    2013-01-01

    Oil palm (Elaeis guineensis) produces two oils of major economic importance, commonly referred to as palm oil and palm kernel oil, extracted from the mesocarp and the endosperm, respectively. While lauric acid predominates in endosperm oil, the major fatty acids (FAs) of mesocarp oil are palmitic and oleic acids. The oil palm embryo also stores oil, which contains a significant proportion of linoleic acid. In addition, the three tissues display high variation for oil content at maturity. To gain insight into the mechanisms that govern such differences in oil content and FA composition, tissue transcriptome and lipid composition were compared during development. The contribution of the cytosolic and plastidial glycolytic routes differed markedly between the mesocarp and seed tissues, but transcriptional patterns of genes involved in the conversion of sucrose to pyruvate were not related to variations for oil content. Accumulation of lauric acid relied on the dramatic up-regulation of a specialized acyl-acyl carrier protein thioesterase paralog and the concerted recruitment of specific isoforms of triacylglycerol assembly enzymes. Three paralogs of the WRINKLED1 (WRI1) transcription factor were identified, of which EgWRI1-1 and EgWRI1-2 were massively transcribed during oil deposition in the mesocarp and the endosperm, respectively. None of the three WRI1 paralogs were detected in the embryo. The transcription level of FA synthesis genes correlated with the amount of WRI1 transcripts and oil content. Changes in triacylglycerol content and FA composition of Nicotiana benthamiana leaves infiltrated with various combinations of WRI1 and FatB paralogs from oil palm validated functions inferred from transcriptome analysis. PMID:23735505

  8. Evolution of Diterpene Metabolism: Sitka Spruce CYP720B4 Catalyzes Multiple Oxidations in Resin Acid Biosynthesis of Conifer Defense against Insects1[C][W][OA

    PubMed Central

    Hamberger, Björn; Ohnishi, Toshiyuki; Hamberger, Britta; Séguin, Armand; Bohlmann, Jörg

    2011-01-01

    Diterpene resin acids (DRAs) are specialized (secondary) metabolites of the oleoresin defense of conifers produced by diterpene synthases and cytochrome P450s of the CYP720B family. The evolution of DRA metabolism shares common origins with the biosynthesis of ent-kaurenoic acid, which is highly conserved in general (primary) metabolism of gibberellin biosynthesis. Transcriptome mining in species of spruce (Picea) and pine (Pinus) revealed CYP720Bs of four distinct clades. We cloned a comprehensive set of 12 different Sitka spruce (Picea sitchensis) CYP720Bs as full-length cDNAs. Spatial expression profiles, methyl jasmonate induction, and transcript enrichment in terpenoid-producing resin ducts suggested a role of CYP720B4 in DRA biosynthesis. CYP720B4 was characterized as a multisubstrate, multifunctional enzyme by the formation of oxygenated diterpenoids in metabolically engineered yeast, yeast in vivo transformation of diterpene substrates, in vitro assays with CYP720B4 protein produced in Escherichia coli, and alteration of DRA profiles in RNA interference-suppressed spruce seedlings. CYP720B4 was active with 24 different diterpenoid substrates, catalyzing consecutive C-18 oxidations in the biosynthesis of an array of diterpene alcohols, aldehydes, and acids. CYP720B4 was most active in the formation of dehydroabietic acid, a compound associated with insect resistance of Sitka spruce. We identified patterns of convergent evolution of CYP720B4 in DRA metabolism and ent-kaurene oxidase CYP701 in gibberellin metabolism and revealed differences in the evolution of specialized and general diterpene metabolism in a gymnosperm. The genomic and functional characterization of the gymnosperm CYP720B family highlights that the evolution of specialized metabolism involves substantial diversification relative to conserved, general metabolism. PMID:21994349

  9. Abscisic Acid-Induced Resistance against the Brown Spot Pathogen Cochliobolus miyabeanus in Rice Involves MAP Kinase-Mediated Repression of Ethylene Signaling1[C][W][OA

    PubMed Central

    De Vleesschauwer, David; Yang, Yinong; Vera Cruz, Casiana; Höfte, Monica

    2010-01-01

    The plant hormone abscisic acid (ABA) is involved in an array of plant processes, including the regulation of gene expression during adaptive responses to various environmental cues. Apart from its well-established role in abiotic stress adaptation, emerging evidence indicates that ABA is also prominently involved in the regulation and integration of pathogen defense responses. Here, we demonstrate that exogenously administered ABA enhances basal resistance of rice (Oryza sativa) against the brown spot-causing ascomycete Cochliobolus miyabeanus. Microscopic analysis of early infection events in control and ABA-treated plants revealed that this ABA-inducible resistance (ABA-IR) is based on restriction of fungal progression in the mesophyll. We also show that ABA-IR does not rely on boosted expression of salicylic acid-, jasmonic acid -, or callose-dependent resistance mechanisms but, instead, requires a functional Gα-protein. In addition, several lines of evidence are presented suggesting that ABA steers its positive effect on brown spot resistance through antagonistic cross talk with the ethylene (ET) response pathway. Exogenous ethephon application enhances susceptibility, whereas genetic disruption of ET signaling renders plants less vulnerable to C. miyabeanus attack, thereby inducing a level of resistance similar to that observed on ABA-treated wild-type plants. Moreover, ABA treatment alleviates C. miyabeanus-induced activation of the ET reporter gene EBP89, while derepression of pathogen-triggered EBP89 transcription via RNA interference-mediated knockdown of OsMPK5, an ABA-primed mitogen-activated protein kinase gene, compromises ABA-IR. Collectively, these data favor a model whereby exogenous ABA enhances resistance against C. miyabeanus at least in part by suppressing pathogen-induced ET action in an OsMPK5-dependent manner. PMID:20130100

  10. Overexpression of a BAHD Acyltransferase, OsAt10, Alters Rice Cell Wall Hydroxycinnamic Acid Content and Saccharification1[C][W][OA

    PubMed Central

    Bartley, Laura E.; Peck, Matthew L.; Kim, Sung-Ryul; Ebert, Berit; Manisseri, Chithra; Chiniquy, Dawn M.; Sykes, Robert; Gao, Lingfang; Rautengarten, Carsten; Vega-Sánchez, Miguel E.; Benke, Peter I.; Canlas, Patrick E.; Cao, Peijian; Brewer, Susan; Lin, Fan; Smith, Whitney L.; Zhang, Xiaohan; Keasling, Jay D.; Jentoff, Rolf E.; Foster, Steven B.; Zhou, Jizhong; Ziebell, Angela; An, Gynheung; Scheller, Henrik V.; Ronald, Pamela C.

    2013-01-01

    Grass cell wall properties influence food, feed, and biofuel feedstock usage efficiency. The glucuronoarabinoxylan of grass cell walls is esterified with the phenylpropanoid-derived hydroxycinnamic acids ferulic acid (FA) and para-coumaric acid (p-CA). Feruloyl esters undergo oxidative coupling with neighboring phenylpropanoids on glucuronoarabinoxylan and lignin. Examination of rice (Oryza sativa) mutants in a grass-expanded and -diverged clade of BAHD acyl-coenzyme A-utilizing transferases identified four mutants with altered cell wall FA or p-CA contents. Here, we report on the effects of overexpressing one of these genes, OsAt10 (LOC_Os06g39390), in rice. An activation-tagged line, OsAT10-D1, shows a 60% reduction in matrix polysaccharide-bound FA and an approximately 300% increase in p-CA in young leaf tissue but no discernible phenotypic alterations in vegetative development, lignin content, or lignin composition. Two additional independent OsAt10 overexpression lines show similar changes in FA and p-CA content. Cell wall fractionation and liquid chromatography-mass spectrometry experiments isolate the cell wall alterations in the mutant to ester conjugates of a five-carbon sugar with p-CA and FA. These results suggest that OsAT10 is a p-coumaroyl coenzyme A transferase involved in glucuronoarabinoxylan modification. Biomass from OsAT10-D1 exhibits a 20% to 40% increase in saccharification yield depending on the assay. Thus, OsAt10 is an attractive target for improving grass cell wall quality for fuel and animal feed. PMID:23391577

  11. Structure-Function Analyses of a Caffeic Acid O-Methyltransferase from Perennial Ryegrass Reveal the Molecular Basis for Substrate Preference[W][OA

    PubMed Central

    Louie, Gordon V.; Bowman, Marianne E.; Tu, Yi; Mouradov, Aidyn; Spangenberg, German; Noel, Joseph P.

    2010-01-01

    Lignin forms from the polymerization of phenylpropanoid-derived building blocks (the monolignols), whose modification through hydroxylation and O-methylation modulates the chemical and physical properties of the lignin polymer. The enzyme caffeic acid O-methyltransferase (COMT) is central to lignin biosynthesis. It is often targeted in attempts to engineer the lignin composition of transgenic plants for improved forage digestibility, pulping efficiency, or utility in biofuel production. Despite intensive investigation, the structural determinants of the regiospecificity and substrate selectivity of COMT remain poorly defined. Reported here are x-ray crystallographic structures of perennial ryegrass (Lolium perenne) COMT (Lp OMT1) in open conformational state, apo- and holoenzyme forms and, most significantly, in a closed conformational state complexed with the products S-adenosyl-l-homocysteine and sinapaldehyde. The product-bound complex reveals the post-methyl-transfer organization of COMT’s catalytic groups with reactant molecules and the fully formed phenolic-ligand binding site. The core scaffold of the phenolic ligand forges a hydrogen-bonding network involving the 4-hydroxy group that anchors the aromatic ring and thereby permits only metahydroxyl groups to be positioned for transmethylation. While distal from the site of transmethylation, the propanoid tail substituent governs the kinetic preference of ryegrass COMT for aldehydes over alcohols and acids due to a single hydrogen bond donor for the C9 oxygenated moiety dictating the preference for an aldehyde. PMID:21177481

  12. Intronic T-DNA Insertion Renders Arabidopsis opr3 a Conditional Jasmonic Acid-Producing Mutant1[C][W][OA

    PubMed Central

    Chehab, E. Wassim; Kim, Se; Savchenko, Tatyana; Kliebenstein, Daniel; Dehesh, Katayoon; Braam, Janet

    2011-01-01

    Jasmonic acid and its derived metabolites (JAs) orchestrate plant defense against insects and fungi. 12-Oxo-phytodienoic acid (OPDA), a JA precursor, has also been implicated in plant defense. We sought to define JAs and OPDA functions through comparative defense susceptibility characteristics of three Arabidopsis (Arabidopsis thaliana) genotypes: aos, lacking JAs and OPDA; opda reductase3 (opr3), deficient in JA production but can accumulate OPDA; and transgenics that overexpress OPR3. opr3, like aos, is susceptible to cabbage loopers (Trichoplusia ni) but, relative to aos, opr3 has enhanced resistance to a necrotrophic fungus. Gas chromatography-mass spectrometry reveals that opr3 produces OPDA but no detectable JAs following wounding and looper infestation; unexpectedly, substantial levels of JAs accumulate in opr3 upon fungal infection. Full-length OPR3 transcripts accumulate in fungal-infected opr3, potentially through splicing of the T-DNA containing intron. Fungal resistance correlates with levels of JAs not OPDA; therefore, opr3 resistance to some pests is likely due to JA accumulation, and signaling activities ascribed to OPDA should be reassessed because opr3 can produce JAs. Together these data (1) reinforce the primary role JAs play in plant defense against insects and necrotrophic fungi, (2) argue for a reassessment of signaling activities ascribed to OPDA, and (3) provide evidence that mutants with intron insertions can retain gene function. PMID:21487047

  13. The Effect of TRANSPARENT TESTA2 on Seed Fatty Acid Biosynthesis and Tolerance to Environmental Stresses during Young Seedling Establishment in Arabidopsis1[W][OA

    PubMed Central

    Chen, Mingxun; Wang, Zhong; Zhu, Yana; Li, Zhilan; Hussain, Nazim; Xuan, Lijie; Guo, Wanli; Zhang, Guoping; Jiang, Lixi

    2012-01-01

    In plants, fatty acids (FAs) and FA-derived complex lipids are major carbon and energy reserves in seeds. They are essential components of cellular membranes and cellular signal or hormone molecules. Although TRANSPARENT TESTA2 (TT2) is well studied for its function in regulating proanthocyanidin biosynthesis in the seed coat, little attention has been given to its role in affecting seed FA accumulation and tolerance to environmental stresses. We demonstrate that the tt2 mutation remarkably increased the seed FA content, decreased seed weight, and altered the FA composition. The increase in FA content in the tt2 seeds was due to the relative decrease of seed coat proportion as well as the more efficient FA synthesis in the tt2 embryo. Microarray analysis revealed that tt2 mutation up-regulated a group of genes critical to FA biosynthesis and embryonic development. The mutation also altered the gene expressions that respond to stress. The microarray analysis discovered that the increase in FA accumulation of the tt2 seeds were accompanied by the significant up-regulation of FUSCA3, a transcriptional factor for embryonic development and FATTY ACID ELONGASE1, which catalyzes the elongation of FA chains. Moreover, lower seed protein accumulation during seed maturation also contributed to the increased seed FA accumulation in tt2 mutants. This study advances the understanding of the TT2 gene in seed FA accumulation and abiotic stresses during seed germination and seedling establishment. PMID:22879396

  14. Oral Allergy Syndrome (OAS). General and stomatological aspects.

    PubMed

    Ausukua, Martina; Dublin, Igone; Echebarria, Maria A; Aguirre, Jose M

    2009-11-01

    Oral Allergy Syndrome (OAS) is a special contact allergy conditioned by specific amino acids in food allergens, usually fruits, as well as some proteins from different pollens. It is usually manifested in the mouth, however relatively little is known about the syndrome in Odontology. OAS is a fairly common adverse reaction that occurs after ingesting certain foods, such as peaches or apples, produced in atopic individuals who usually suffer from rhinitis, bronchial asthma or both. This syndrome mainly affects the oral cavity and oropharynx, provoking minor local alterations, although there may be serious systematic reactions, making it important to distinguish it from other oral processes when making the diagnosis. One of the more severe forms of OAS is anaphylaxis, which is food-induced. In this study, we will analyze the key etiopathogenic, clinical and therapeutic aspects of this syndrome, focusing specifically on the stomatological aspects.

  15. Cytokinins Mediate Resistance against Pseudomonas syringae in Tobacco through Increased Antimicrobial Phytoalexin Synthesis Independent of Salicylic Acid Signaling1[W][OA

    PubMed Central

    Großkinsky, Dominik K.; Naseem, Muhammad; Abdelmohsen, Usama Ramadan; Plickert, Nicole; Engelke, Thomas; Griebel, Thomas; Zeier, Jürgen; Novák, Ondřej; Strnad, Miroslav; Pfeifhofer, Hartwig; van der Graaff, Eric; Simon, Uwe; Roitsch, Thomas

    2011-01-01

    Cytokinins are phytohormones that are involved in various regulatory processes throughout plant development, but they are also produced by pathogens and known to modulate plant immunity. A novel transgenic approach enabling autoregulated cytokinin synthesis in response to pathogen infection showed that cytokinins mediate enhanced resistance against the virulent hemibiotrophic pathogen Pseudomonas syringae pv tabaci. This was confirmed by two additional independent transgenic approaches to increase endogenous cytokinin production and by exogenous supply of adenine- and phenylurea-derived cytokinins. The cytokinin-mediated resistance strongly correlated with an increased level of bactericidal activities and up-regulated synthesis of the two major antimicrobial phytoalexins in tobacco (Nicotiana tabacum), scopoletin and capsidiol. The key role of these phytoalexins in the underlying mechanism was functionally proven by the finding that scopoletin and capsidiol substitute in planta for the cytokinin signal: phytoalexin pretreatment increased resistance against P. syringae. In contrast to a cytokinin defense mechanism in Arabidopsis (Arabidopsis thaliana) based on salicylic acid-dependent transcriptional control, the cytokinin-mediated resistance in tobacco is essentially independent from salicylic acid and differs in pathogen specificity. It is also independent of jasmonate levels, reactive oxygen species, and high sugar resistance. The novel function of cytokinins in the primary defense response of solanaceous plant species is rather mediated through a high phytoalexin-pathogen ratio in the early phase of infection, which efficiently restricts pathogen growth. The implications of this mechanism for the coevolution of host plants and cytokinin-producing pathogens and the practical application in agriculture are discussed. PMID:21813654

  16. An Amino Acid Substitution Inhibits Specialist Herbivore Production of an Antagonist Effector and Recovers Insect-Induced Plant Defenses1[W][OA

    PubMed Central

    Schmelz, Eric A.; Huffaker, Alisa; Carroll, Mark J.; Alborn, Hans T.; Ali, Jared G.; Teal, Peter E.A.

    2012-01-01

    Plants respond to insect herbivory through the production of biochemicals that function as either direct defenses or indirect defenses via the attraction of natural enemies. While attack by closely related insect pests can result in distinctive levels of induced plant defenses, precise biochemical mechanisms responsible for differing responses remain largely unknown. Cowpea (Vigna unguiculata) responds to Fall armyworm (Spodoptera frugiperda) herbivory through the detection of fragments of chloroplastic ATP synthase γ-subunit proteins, termed inceptin-related peptides, present in larval oral secretions (OS). In contrast to generalists like Fall armyworm, OS of the legume-specializing velvetbean caterpillar (VBC; Anticarsia gemmatalis) do not elicit ethylene production and demonstrate significantly lower induced volatile emission in direct herbivory comparisons. Unlike all other Lepidoptera OS examined, which preferentially contain inceptin (Vu-In; +ICDINGVCVDA−), VBC OS contain predominantly a C-terminal truncated peptide, Vu-In−A (+ICDINGVCVD−). Vu-In−A is both inactive and functions as a potent naturally occurring antagonist of Vu-In-induced responses. To block antagonist production, amino acid substitutions at the C terminus were screened for differences in VBC gut proteolysis. A valine-substituted peptide (Vu-InΔV; +ICDINGVCVDV−) retaining full elicitor activity was found to accumulate in VBC OS. Compared with the native polypeptide, VBC that previously ingested 500 pmol of the valine-modified chloroplastic ATP synthase γ-subunit precursor elicited significantly stronger plant responses in herbivory assays. We demonstrate that a specialist herbivore minimizes the activation of defenses by converting an elicitor into an antagonist effector and identify an amino acid substitution that recovers these induced plant defenses to a level observed with generalist herbivores. PMID:23008466

  17. Metabolic Engineering of Seeds Can Achieve Levels of ω-7 Fatty Acids Comparable with the Highest Levels Found in Natural Plant Sources1[OA

    PubMed Central

    Nguyen, Huu Tam; Mishra, Girish; Whittle, Edward; Pidkowich, Mark S.; Bevan, Scott A.; Merlo, Ann Owens; Walsh, Terence A.; Shanklin, John

    2010-01-01

    Plant oils containing ω-7 fatty acids (FAs; palmitoleic 16:1Δ9 and cis-vaccenic 18:1Δ11) have potential as sustainable feedstocks for producing industrially important octene via metathesis chemistry. Engineering plants to produce seeds that accumulate high levels of any unusual FA has been an elusive goal. We achieved high levels of ω-7 FA accumulation by systematic metabolic engineering of Arabidopsis (Arabidopsis thaliana). A plastidial 16:0-ACP desaturase has been engineered to convert 16:0 to 16:1Δ9 with specificity >100-fold than that of naturally occurring paralogs, such as that from cat's claw vine (Doxantha unguis-cati). Expressing this engineered enzyme (Com25) in seeds increased ω-7 FA accumulation from <2% to 14%. Reducing competition for 16:0-ACP by down-regulating the β-ketoacyl-ACP synthase II 16:0 elongase further increased accumulation of ω-7 FA to 56%. The level of 16:0 exiting the plastid without desaturation also increased to 21%. Coexpression of a pair of fungal 16:0 desaturases in the cytosol reduced the 16:0 level to 11% and increased ω-7 FA to as much as 71%, equivalent to levels found in Doxantha seeds. PMID:20943853

  18. A Plasma Membrane Receptor Kinase, GHR1, Mediates Abscisic Acid- and Hydrogen Peroxide-Regulated Stomatal Movement in Arabidopsis[W][OA

    PubMed Central

    Hua, Deping; Wang, Cun; He, Junna; Liao, Hui; Duan, Ying; Zhu, Ziqiang; Guo, Yan; Chen, Zhizhong; Gong, Zhizhong

    2012-01-01

    The plant hormone abscisic acid (ABA) regulates stomatal movement under drought stress, and this regulation requires hydrogen peroxide (H2O2). We isolated GUARD CELL HYDROGEN PEROXIDE-RESISTANT1 (GHR1), which encodes a receptor-like kinase localized on the plasma membrane in Arabidopsis thaliana. ghr1 mutants were defective ABA and H2O2 induction of stomatal closure. Genetic analysis indicates that GHR1 is a critical early component in ABA signaling. The ghr1 mutation impaired ABA- and H2O2-regulated activation of S-type anion currents in guard cells. Furthermore, GHR1 physically interacted with, phosphorylated, and activated the S-type anion channel SLOW ANION CHANNEL-ASSOCIATED1 when coexpressed in Xenopus laevis oocytes, and this activation was inhibited by ABA-INSENSITIVE2 (ABI2) but not ABI1. Our study identifies a critical component in ABA and H2O2 signaling that is involved in stomatal movement and resolves a long-standing mystery about the differential functions of ABI1 and ABI2 in this process. PMID:22730405

  19. Novel Plant Immune-Priming Compounds Identified via High-Throughput Chemical Screening Target Salicylic Acid Glucosyltransferases in Arabidopsis[W][OA

    PubMed Central

    Noutoshi, Yoshiteru; Okazaki, Masateru; Kida, Tatsuya; Nishina, Yuta; Morishita, Yoshihiko; Ogawa, Takumi; Suzuki, Hideyuki; Shibata, Daisuke; Jikumaru, Yusuke; Hanada, Atsushi; Kamiya, Yuji

    2012-01-01

    Plant activators are compounds, such as analogs of the defense hormone salicylic acid (SA), that protect plants from pathogens by activating the plant immune system. Although some plant activators have been widely used in agriculture, the molecular mechanisms of immune induction are largely unknown. Using a newly established high-throughput screening procedure that screens for compounds that specifically potentiate pathogen-activated cell death in Arabidopsis thaliana cultured suspension cells, we identified five compounds that prime the immune response. These compounds enhanced disease resistance against pathogenic Pseudomonas bacteria in Arabidopsis plants. Pretreatments increased the accumulation of endogenous SA, but reduced its metabolite, SA-O-β-d-glucoside. Inducing compounds inhibited two SA glucosyltransferases (SAGTs) in vitro. Double knockout plants that lack both SAGTs consistently exhibited enhanced disease resistance. Our results demonstrate that manipulation of the active free SA pool via SA-inactivating enzymes can be a useful strategy for fortifying plant disease resistance and may identify useful crop protectants. PMID:22960909

  20. Early Induction of Apple Fruitlet Abscission Is Characterized by an Increase of Both Isoprene Emission and Abscisic Acid Content12[W][OA

    PubMed Central

    Giulia, Eccher; Alessandro, Botton; Mariano, Dimauro; Andrea, Boschetti; Benedetto, Ruperti; Angelo, Ramina

    2013-01-01

    Apple (Malus domestica) fruitlet abscission represents an interesting model system to study the early phases of the shedding process, during which major transcriptomic changes and metabolic rearrangements occur within the fruit. In apple, the drop of fruits at different positions within the cluster can be selectively magnified through chemical thinners, such as benzyladenine and metamitron, acting as abscission enhancers. In this study, different abscission potentials were obtained within the apple fruitlet population by means of the above-cited thinners. A metabolomic study was conducted on the volatile organic compounds emitted by abscising fruitlets, allowing for identification of isoprene as an early marker of abscission induction. A strong correlation was also observed between isoprene production and abscisic acid (ABA) levels in the fruit cortex, which were shown to increase in abscising fruitlets with respect to nonabscising ones. Transcriptomic evidence indicated that abscission-related ABA is biologically active, and its increased biosynthesis is associated with the induction of a specific ABA-responsive 9-cis-epoxycarotenoid dioxygenase gene. According to a hypothetical model, ABA may transiently cooperate with other hormones and secondary messengers in the generation of an intrafruit signal leading to the downstream activation of the abscission zone. The shedding process therefore appears to be triggered by multiple interdependent pathways, whose fine regulation, exerted within a very short temporal window by both endogenous and exogenous factors, determines the final destiny of the fruitlets. PMID:23444344

  1. Abscisic Acid Deficiency Causes Changes in Cuticle Permeability and Pectin Composition That Influence Tomato Resistance to Botrytis cinerea1[C][W][OA

    PubMed Central

    Curvers, Katrien; Seifi, Hamed; Mouille, Grégory; de Rycke, Riet; Asselbergh, Bob; Van Hecke, Annelies; Vanderschaeghe, Dieter; Höfte, Herman; Callewaert, Nico; Van Breusegem, Frank; Höfte, Monica

    2010-01-01

    A mutant of tomato (Solanum lycopersicum) with reduced abscisic acid (ABA) production (sitiens) exhibits increased resistance to the necrotrophic fungus Botrytis cinerea. This resistance is correlated with a rapid and strong hydrogen peroxide-driven cell wall fortification response in epidermis cells that is absent in tomato with normal ABA production. Moreover, basal expression of defense genes is higher in the mutant compared with the wild-type tomato. Given the importance of this fast response in sitiens resistance, we investigated cell wall and cuticle properties of the mutant at the chemical, histological, and ultrastructural levels. We demonstrate that ABA deficiency in the mutant leads to increased cuticle permeability, which is positively correlated with disease resistance. Furthermore, perturbation of ABA levels affects pectin composition. sitiens plants have a relatively higher degree of pectin methylesterification and release different oligosaccharides upon inoculation with B. cinerea. These results show that endogenous plant ABA levels affect the composition of the tomato cuticle and cell wall and demonstrate the importance of cuticle and cell wall chemistry in shaping the outcome of this plant-fungus interaction. PMID:20709830

  2. Suppression of 9-cis-Epoxycarotenoid Dioxygenase, Which Encodes a Key Enzyme in Abscisic Acid Biosynthesis, Alters Fruit Texture in Transgenic Tomato1[W][OA

    PubMed Central

    Sun, Liang; Sun, Yufei; Zhang, Mei; Wang, Ling; Ren, Jie; Cui, Mengmeng; Wang, Yanping; Ji, Kai; Li, Ping; Li, Qian; Chen, Pei; Dai, Shengjie; Duan, Chaorui; Wu, Yan; Leng, Ping

    2012-01-01

    Cell wall catabolism during fruit ripening is under complex control and is key for fruit quality and shelf life. To examine the role of abscisic acid (ABA) in tomato (Solanum lycopersicum) fruit ripening, we suppressed SlNCED1, which encodes 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in the biosynthesis of ABA. To suppress SlNCED1 specifically in tomato fruits, and thus avoid the pleiotropic phenotypes associated with ABA deficiency, we used an RNA interference construct driven by the fruit-specific E8 promoter. ABA accumulation and SlNCED1 transcript levels in the transgenic fruit were down-regulated to between 20% and 50% of the levels measured in the control fruit. This significant reduction in NCED activity led to a down-regulation in the transcription of genes encoding major cell wall catabolic enzymes, specifically polygalacturonase (SlPG), pectin methyl esterase (SlPME), β-galactosidase precursor mRNA (SlTBG), xyloglucan endotransglycosylase (SlXET), endo-1,4-β-cellulose (SlCels), and expansin (SlExp). This resulted in an increased accumulation of pectin during ripening. In turn, this led to a significant extension of the shelf life to 15 to 29 d compared with a shelf life of only 7 d for the control fruit and an enhancement of fruit firmness at the mature stage by 30% to 45%. In conclusion, ABA affects cell wall catabolism during tomato fruit ripening via down-regulation of the expression of major catabolic genes (SlPG, SlPME, SlTBG, SlXET, SlCels, and SlExp). PMID:22108525

  3. The Manipulation of Auxin in the Abscission Zone Cells of Arabidopsis Flowers Reveals That Indoleacetic Acid Signaling Is a Prerequisite for Organ Shedding1[C][W][OA

    PubMed Central

    Basu, Manojit M.; González-Carranza, Zinnia H.; Azam-Ali, Sayed; Tang, Shouya; Shahid, Ahmad Ali; Roberts, Jeremy A.

    2013-01-01

    A number of novel strategies were employed to examine the role of indoleacetic acid (IAA) in regulating floral organ abscission in Arabidopsis (Arabidopsis thaliana). Analysis of auxin influx facilitator expression in β-glucuronidase reporter plants revealed that AUXIN RESISTANT1, LIKE AUX1, and LAX3 were specifically up-regulated at the site of floral organ shedding. Flowers from mutants where individual family members were down-regulated exhibited a reduction in the force necessary to bring about petal separation; however, the effect was not additive in double or quadruple mutants. Using the promoter of a polygalacturonase (At2g41850), active primarily in cells undergoing separation, to drive expression of the bacterial genes iaaL and iaaM, we have shown that it is possible to manipulate auxin activity specifically within the floral organ abscission zone (AZ). Analysis of petal breakstrength reveals that if IAA AZ levels are reduced, shedding takes place prematurely, while if they are enhanced, organ loss is delayed. The At2g41850 promoter was also used to transactivate the gain-of-function AXR3-1 gene in order to disrupt auxin signaling specifically within the floral organ AZ cells. Flowers from transactivated lines failed to shed their sepals, petals, and anthers during pod expansion and maturity, and these organs frequently remained attached to the plant even after silique desiccation and dehiscence had taken place. These observations support a key role for IAA in the regulation of abscission in planta and reveal, to our knowledge for the first time, a requirement for a functional IAA signaling pathway in AZ cells for organ shedding to take place. PMID:23509178

  4. Pithy Protection: Nicotiana attenuata’s Jasmonic Acid-Mediated Defenses Are Required to Resist Stem-Boring Weevil Larvae1[W][OA

    PubMed Central

    Diezel, Celia; Kessler, Danny; Baldwin, Ian T.

    2011-01-01

    Folivory is the best studied plant-herbivore interaction, but it is unclear whether the signaling and resistance traits important for the defense of leaves are also important for other plant parts. Larvae of the tobacco stem weevil, Trichobaris mucorea, burrow into stems of Nicotiana attenuata and feed on the pith. Transgenic N. attenuata lines silenced in signaling and foliar defense traits were evaluated in a 2-year field study for resistance against attack by naturally occurring T. mucorea larva. Plants silenced in early jasmonic acid (JA) biosynthesis (antisense [as]-lipoxygenase3 [lox3]; inverted repeat [ir]-allene oxide cyclase), JA perception (as-coronatine insensitive1), proteinase inhibitors (ir-pi), and nicotine (ir-putrescine methyl-transferase) direct defenses and lignin (ir-cad) biosynthesis were infested more frequently than wild-type plants. Plants unable to emit C6 aldehydes (as-hpl) had lower infestation rates, while plants silenced in late steps in JA biosynthesis (ir-acyl-coenzyme A oxidase, ir-opr) and silenced in diterpene glycoside production (ir-geranylgeranyl pyrophosphate synthase) did not differ from wild type. Pith choice assays revealed that ir-putrescine methyl-transferase, ir-coronatine insensitive1, and ir-lox3 pith, which all had diminished nicotine levels, were preferred by larvae compared to wild-type pith. The lack of preference for ir-lox2 and ir-cad piths, suggest that oviposition attraction and vascular defense, rather than pith palatability accounts for the higher attack rates observed for these plants. We conclude that traits that influence a plant’s apparency, stem hardness, and pith direct defenses all contribute to resistance against this herbivore whose attack can be devastating to N. attenuata’s fitness. PMID:21300916

  5. Gene Expression and Metabolite Profiling of Developing Highbush Blueberry Fruit Indicates Transcriptional Regulation of Flavonoid Metabolism and Activation of Abscisic Acid Metabolism1[W][OA

    PubMed Central

    Zifkin, Michael; Jin, Alena; Ozga, Jocelyn A.; Zaharia, L. Irina; Schernthaner, Johann P.; Gesell, Andreas; Abrams, Suzanne R.; Kennedy, James A.; Constabel, C. Peter

    2012-01-01

    Highbush blueberry (Vaccinium corymbosum) fruits contain substantial quantities of flavonoids, which are implicated in a wide range of health benefits. Although the flavonoid constituents of ripe blueberries are known, the molecular genetics underlying their biosynthesis, localization, and changes that occur during development have not been investigated. Two expressed sequence tag libraries from ripening blueberry fruit were constructed as a resource for gene identification and quantitative real-time reverse transcription-polymerase chain reaction primer design. Gene expression profiling by quantitative real-time reverse transcription-polymerase chain reaction showed that flavonoid biosynthetic transcript abundance followed a tightly regulated biphasic pattern, and transcript profiles were consistent with the abundance of the three major classes of flavonoids. Proanthocyanidins (PAs) and corresponding biosynthetic transcripts encoding anthocyanidin reductase and leucoanthocyanidin reductase were most concentrated in young fruit and localized predominantly to the inner fruit tissue containing the seeds and placentae. Mean PA polymer length was seven to 8.5 subunits, linked predominantly via B-type linkages, and was relatively constant throughout development. Flavonol accumulation and localization patterns were similar to those of the PAs, and the B-ring hydroxylation pattern of both was correlated with flavonoid-3′-hydroxylase transcript abundance. By contrast, anthocyanins accumulated late in maturation, which coincided with a peak in flavonoid-3-O-glycosyltransferase and flavonoid-3′5′-hydroxylase transcripts. Transcripts of VcMYBPA1, which likely encodes an R2R3-MYB transcriptional regulator of PA synthesis, were prominent in both phases of development. Furthermore, the initiation of ripening was accompanied by a substantial rise in abscisic acid, a growth regulator that may be an important component of the ripening process and contribute to the regulation

  6. Nicotiana attenuata SIPK, WIPK, NPR1, and Fatty Acid-Amino Acid Conjugates Participate in the Induction of Jasmonic Acid Biosynthesis by Affecting Early Enzymatic Steps in the Pathway1[W][OA

    PubMed Central

    Kallenbach, Mario; Alagna, Fiammetta; Baldwin, Ian Thomas; Bonaventure, Gustavo

    2010-01-01

    Wounding and herbivore attack elicit the rapid (within minutes) accumulation of jasmonic acid (JA) that results from the activation of previously synthesized biosynthetic enzymes. Recently, several regulatory factors that affect JA production have been identified; however, how these regulators affect JA biosynthesis remains at present unknown. Here we demonstrate that Nicotiana attenuata salicylate-induced protein kinase (SIPK), wound-induced protein kinase (WIPK), nonexpressor of PR-1 (NPR1), and the insect elicitor N-linolenoyl-glucose (18:3-Glu) participate in mechanisms affecting early enzymatic steps of the JA biosynthesis pathway. Plants silenced in the expression of SIPK and NPR1 were affected in the initial accumulation of 13-hydroperoxy-linolenic acid (13-OOH-18:3) after wounding and 18:3-Glu elicitation by mechanisms independent of changes in 13-lipoxygenase activity. Moreover, 18:3-Glu elicited an enhanced and rapid accumulation of 13-OOH-18:3 that depended partially on SIPK and NPR1 but was independent of increased 13-lipoxygenase activity. Together, the results suggested that substrate supply for JA production was altered by 18:3-Glu elicitation and SIPK- and NPR1-mediated mechanisms. Consistent with a regulation at the level of substrate supply, we demonstrated by virus-induced gene silencing that a wound-repressed plastidial glycerolipase (NaGLA1) plays an essential role in the induction of de novo JA biosynthesis. In contrast to SIPK and NPR1, mechanisms mediated by WIPK did not affect the production of 13-OOH-18:3 but were critical to control the conversion of this precursor into 12-oxo-phytodienoic acid. These differences could be partially accounted for by reduced allene oxide synthase activity in WIPK-silenced plants. PMID:19897603

  7. Long-term balancing selection at the antiviral gene OAS1 in Central African chimpanzees.

    PubMed

    Ferguson, William; Dvora, Shira; Fikes, Ronald W; Stone, Anne C; Boissinot, Stéphane

    2012-04-01

    Oligoadenylate synthetases (OAS) are interferon-induced enzymes that participate in the first line of defense against a wide range of viral infection in animals. Upon activation by viral double-stranded RNA, OAS synthesizes (2-5) oligoadenylates, which activate RNase L, leading to the nonspecific degradation of cellular and viral RNA. Some association studies in humans suggest that variation at one of the OAS genes, OAS1, could be influencing host susceptibility to viral infection. We assessed the diversity of OAS1 in hominoid primates with a focus on chimpanzees. We found that the OAS1 gene is extremely polymorphic in Central African chimpanzee and exhibits levels of silent and replacement diversity much higher than neutral regions of the chimpanzee genome. This level of variation strongly suggests that balancing selection is acting on OAS1, and indeed, this conclusion was validated by several tests of neutrality. We further demonstrated that balancing selection has been acting at this locus since the split between chimpanzees, humans, and gorillas (~8.6 Ma) and caused the persistence of two deeply divergent allelic lineages in Central African chimpanzees. These two groups of OAS1 alleles differ by a large number of amino acids (a.a.), including several a.a. putatively involved in RNA binding. It is therefore very likely that variation at the OAS1 locus affects the innate immune response of individuals to specific viral infection. Our data strongly suggest that interactions between viral RNA and OAS1 are responsible for the maintenance of ancestral polymorphisms at this locus for at least 13.2 My.

  8. OBE, Effective Schools and NCA's OA: Romance or Feud?

    ERIC Educational Resources Information Center

    Armstrong, Robert L.

    1992-01-01

    Explains the North Central Association's Outcomes Accreditation (OA) alternative to traditional accreditation status. Reviews the Effective Schools and Outcome-Based Education (OBE) literature, and considers basic requirements for OA. Considers OBE compatible with OA. (DMM)

  9. Perturbations of Amino Acid Metabolism Associated with Glyphosate-Dependent Inhibition of Shikimic Acid Metabolism Affect Cellular Redox Homeostasis and Alter the Abundance of Proteins Involved in Photosynthesis and Photorespiration1[W][OA

    PubMed Central

    Vivancos, Pedro Diaz; Driscoll, Simon P.; Bulman, Christopher A.; Ying, Liu; Emami, Kaveh; Treumann, Achim; Mauve, Caroline; Noctor, Graham; Foyer, Christine H.

    2011-01-01

    The herbicide glyphosate inhibits the shikimate pathway of the synthesis of amino acids such as phenylalanine, tyrosine, and tryptophan. However, much uncertainty remains concerning precisely how glyphosate kills plants or affects cellular redox homeostasis and related processes in glyphosate-sensitive and glyphosate-resistant crop plants. To address this issue, we performed an integrated study of photosynthesis, leaf proteomes, amino acid profiles, and redox profiles in the glyphosate-sensitive soybean (Glycine max) genotype PAN809 and glyphosate-resistant Roundup Ready Soybean (RRS). RRS leaves accumulated much more glyphosate than the sensitive line but showed relatively few changes in amino acid metabolism. Photosynthesis was unaffected by glyphosate in RRS leaves, but decreased abundance of photosynthesis/photorespiratory pathway proteins was observed together with oxidation of major redox pools. While treatment of a sensitive genotype with glyphosate rapidly inhibited photosynthesis and triggered the appearance of a nitrogen-rich amino acid profile, there was no evidence of oxidation of the redox pools. There was, however, an increase in starvation-associated and defense proteins. We conclude that glyphosate-dependent inhibition of soybean leaf metabolism leads to the induction of defense proteins without sustained oxidation. Conversely, the accumulation of high levels of glyphosate in RRS enhances cellular oxidation, possibly through mechanisms involving stimulation of the photorespiratory pathway. PMID:21757634

  10. The ocular albinism type 1 gene product, OA1, spans intracellular membranes 7 times.

    PubMed

    Sone, Michio; Orlow, Seth J

    2007-12-01

    OA1 (GPR143) is a pigment cell-specific intracellular glycoprotein consisting of 404 amino acid residues that is mutated in patients with ocular albinism type 1, the most common form of ocular albinism. While its cellular localization is suggested to be endolysosomal and melanosomal, the physiological function of OA1 is currently unclear. Recent reports predicted that OA1 functions as a G protein coupled receptor (GPCR) based on its weak amino acid sequence similarity to known GPCRs, and on demonstration of GPCR activity in OA1 mislocalized to the plasma membrane. Because mislocalization of proteins is often caused by or induces defects in their proper folding/assembly, the significance of these studies remains unclear. A characteristic feature of GPCRs is a seven transmembrane domain structure. We analyzed the membrane topology of OA1 properly localized to intracellular lysosomal organelles in COS-1 cells. To accomplish this analysis, we established experimental conditions that allowed selective permeabilization of the plasma membrane while leaving endolysosomal membranes intact. Domains were mapped by the insertion of a hemagglutinin (HA) tag into the predicted cytosolic/luminal regions of OA1 molecule and the accessibility of tag to HA antibody was determined by immunofluorescence. HA-tagged lysosome associated membrane protein 1 (LAMP1), a type I membrane protein, was employed as a reporter for selective permeabilization of the plasma membrane. Our results show experimentally that the C-terminus of OA1 is directed to the cytoplasm and that the protein spans the intracellular membrane 7 times. Thus, OA1, properly localized intracellularly, is a 7 transmembrane domain integral membrane protein consistent with its putative role as an intracellular GPCR.

  11. Long-term balancing selection at the west nile virus resistance gene, Oas1b, maintains transspecific polymorphisms in the house mouse.

    PubMed

    Ferguson, William; Dvora, Shira; Gallo, Juliana; Orth, Annie; Boissinot, Stéphane

    2008-08-01

    Oligoadenylate synthetases (OASs) are interferon-inducible enzymes that participate in the first line of defense against a wide range of viral infection. Recent studies have determined that Oas1b, a member of the OAS gene family in the house mouse (Mus musculus), provides specific protection against flavivirus infection (e.g., West Nile virus, dengue fever virus, and yellow fever virus). We characterized the nucleotide sequence variation in coding and noncoding regions of the Oas1b gene for a large number of wild-derived strains of M. musculus and related species. Our sequence analyses determined that this gene is one of the most polymorphic genes ever described in any mammal. The level of variation in noncoding regions of Oas1b is an order of magnitude higher than the level reported for other regions of the mouse genome and is significantly different from the level of intraspecific variation expected under neutrality. Furthermore, a phylogenetic analysis of intronic sequences demonstrated that Oas1b alleles are ancient and that their divergence predates several speciation events, resulting in transspecific polymorphisms. The amino acid sequence of Oas1b is also extremely variable, with 1 out of 7 amino acid positions being polymorphic within M. musculus. Oas1b alleles are comparatively more divergent at synonymous positions than most autosomal genes and the ratio of nonsynonymous to synonymous substitution is remarkably high, suggesting that positive selection has been acting on Oas1b. The ancestry of Oas1b polymorphisms and the high level of amino acid polymorphisms strongly suggest that the allelic variation at Oas1b has been maintained in mouse populations by long-term balancing selection.

  12. CYP86B1 Is Required for Very Long Chain ω-Hydroxyacid and α,ω-Dicarboxylic Acid Synthesis in Root and Seed Suberin Polyester1[W][OA

    PubMed Central

    Compagnon, Vincent; Diehl, Patrik; Benveniste, Irène; Meyer, Denise; Schaller, Hubert; Schreiber, Lukas; Franke, Rochus; Pinot, Franck

    2009-01-01

    Suberin composition of various plants including Arabidopsis (Arabidopsis thaliana) has shown the presence of very long chain fatty acid derivatives C20 in addition to the C16 and C18 series. Phylogenetic studies and plant genome mining have led to the identification of putative aliphatic hydroxylases belonging to the CYP86B subfamily of cytochrome P450 monooxygenases. In Arabidopsis, this subfamily is represented by CYP86B1 and CYP86B2, which share about 45% identity with CYP86A1, a fatty acid ω-hydroxylase implicated in root suberin monomer synthesis. Here, we show that CYP86B1 is located to the endoplasmic reticulum and is highly expressed in roots. Indeed, CYP86B1 promoter-driven β-glucuronidase expression indicated strong reporter activities at known sites of suberin production such as the endodermis. These observations, together with the fact that proteins of the CYP86B type are widespread among plant species, suggested a role of CYP86B1 in suberin biogenesis. To investigate the involvement of CYP86B1 in suberin biogenesis, we characterized an allelic series of cyp86B1 mutants of which two strong alleles were knockouts and two weak ones were RNA interference-silenced lines. These root aliphatic plant hydroxylase lines had a root and a seed coat aliphatic polyester composition in which C22- and C24-hydroxyacids and α,ω-dicarboxylic acids were strongly reduced. However, these changes did not affect seed coat permeability and ion content in leaves. The presumed precursors, C22 and C24 fatty acids, accumulated in the suberin polyester. These results demonstrate that CYP86B1 is a very long chain fatty acid hydroxylase specifically involved in polyester monomer biosynthesis during the course of plant development. PMID:19525321

  13. A facile strategy to synthesize monodisperse superparamagnetic OA-modified Fe3O4 nanoparticles with PEG assistant

    NASA Astrophysics Data System (ADS)

    Sun, Minmin; Zhu, Aimei; Zhang, Qiugen; Liu, Qinglin

    2014-11-01

    A facile strategy was reported to synthesize monodisperse super-paramagnetic oleic acid (OA) modified Fe3O4 nanoparticles, which the poly ethylene glycol (PEG) was used as the assistant. The influence of the molecular weight and concentration of PEG was investigated in the process of OA-modification. In addition, the mechanism of PEG action in the reaction system was discussed. The morphology and properties of the as-synthesized Fe3O4 magnetic nanoparticles were characterized by the scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and superconducting quantum interference device (SQUID). The size (12 nm) of the as-prepared Fe3O4 nanoparticles is smaller than the superparamagnetic critical size (25 nm) of Fe3O4 nanoparticles, which endows the OA-modified Fe3O4 nanoparticles with superparamagnetic property. Furthermore, the dispersibility and stability of as-synthesized OA-modified Fe3O4 magnetic nanoparticles were very good. As the stabilizer and dispersant, PEG played a very important role and did not encapsulate the OA-modified Fe3O4 nanoparticles. The condition for OA-modified Fe3O4 nanoparticles preparation was optimized.

  14. Overexpression of the Trehalase Gene AtTRE1 Leads to Increased Drought Stress Tolerance in Arabidopsis and Is Involved in Abscisic Acid-Induced Stomatal Closure1[W][OA

    PubMed Central

    Van Houtte, Hilde; Vandesteene, Lies; López-Galvis, Lorena; Lemmens, Liesbeth; Kissel, Ewaut; Carpentier, Sebastien; Feil, Regina; Avonce, Nelson; Beeckman, Tom; Lunn, John E.; Van Dijck, Patrick

    2013-01-01

    Introduction of microbial trehalose biosynthesis enzymes has been reported to enhance abiotic stress resistance in plants but also resulted in undesirable traits. Here, we present an approach for engineering drought stress tolerance by modifying the endogenous trehalase activity in Arabidopsis (Arabidopsis thaliana). AtTRE1 encodes the Arabidopsis trehalase, the only enzyme known in this species to specifically hydrolyze trehalose into glucose. AtTRE1-overexpressing and Attre1 mutant lines were constructed and tested for their performance in drought stress assays. AtTRE1-overexpressing plants had decreased trehalose levels and recovered better after drought stress, whereas Attre1 mutants had elevated trehalose contents and exhibited a drought-susceptible phenotype. Leaf detachment assays showed that Attre1 mutants lose water faster than wild-type plants, whereas AtTRE1-overexpressing plants have a better water-retaining capacity. In vitro studies revealed that abscisic acid-mediated closure of stomata is impaired in Attre1 lines, whereas the AtTRE1 overexpressors are more sensitive toward abscisic acid-dependent stomatal closure. This observation is further supported by the altered leaf temperatures seen in trehalase-modified plantlets during in vivo drought stress studies. Our results show that overexpression of plant trehalase improves drought stress tolerance in Arabidopsis and that trehalase plays a role in the regulation of stomatal closure in the plant drought stress response. PMID:23341362

  15. Powdery Mildew Resistance Conferred by Loss of the ENHANCED DISEASE RESISTANCE1 Protein Kinase Is Suppressed by a Missense Mutation in KEEP ON GOING, a Regulator of Abscisic Acid Signaling1[W][OA

    PubMed Central

    Wawrzynska, Anna; Christiansen, Katy M.; Lan, Yinan; Rodibaugh, Natalie L.; Innes, Roger W.

    2008-01-01

    Loss-of-function mutations in the Arabidopsis (Arabidopsis thaliana) ENHANCED DISEASE RESISTANCE1 (EDR1) gene confer enhanced resistance to infection by powdery mildew (Golovinomyces cichoracearum). EDR1 encodes a protein kinase, but its substrates and the pathways regulated by EDR1 are unknown. To identify components of the EDR1 signal transduction pathway(s), we conducted a forward genetic screen for mutations that suppressed edr1-mediated disease resistance. Genetic mapping and cloning of one of these suppressor mutations revealed a recessive missense mutation in the KEEP ON GOING gene (KEG; At5g13530), which we designated keg-4. KEG encodes a multidomain protein that includes a RING E3 ligase domain, a kinase domain, ankyrin repeats, and HERC2-like repeats. The KEG protein has previously been shown to have ubiquitin ligase activity and to negatively regulate protein levels of the transcription factor ABCISIC ACID INSENSITIVE5. KEG mRNA levels were found to be 3-fold higher in edr1 mutant plants compared to wild type. Loss-of-function mutations in KEG are seedling lethal and are hypersensitive to glucose and abscisic acid (ABA). The keg-4 mutation, in contrast, conferred resistance to 6% glucose and suppressed edr1-mediated hypersensitivity to ABA, suggesting that the keg-4 mutation suppresses ABA signaling by altering KEG function. Several ABA-responsive genes were found to be further up-regulated in the edr1 mutant following ABA treatment, and this up-regulation was suppressed by the keg-4 mutation. We conclude that edr1-mediated resistance to powdery mildew is mediated, in part, by enhanced ABA signaling. PMID:18815384

  16. 41 CFR 102-85.140 - How are changes in Rent reflected in OAs?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... reflected in OAs? 102-85.140 Section 102-85.140 Public Contracts and Property Management Federal Property... OCCUPANCY IN GSA SPACE Rent Charges § 102-85.140 How are changes in Rent reflected in OAs? (a) If Rent changes in ways that are identified in the OA, then no change to the OA is required. Typically, OAs...

  17. The Pepper E3 Ubiquitin Ligase RING1 Gene, CaRING1, Is Required for Cell Death and the Salicylic Acid-Dependent Defense Response1[C][W][OA

    PubMed Central

    Lee, Dong Hyuk; Choi, Hyong Woo; Hwang, Byung Kook

    2011-01-01

    Ubiquitination is essential for ubiquitin/proteasome-mediated protein degradation in plant development and defense. Here, we identified a novel E3 ubiquitin ligase RING1 gene, CaRING1, from pepper (Capsicum annuum). In pepper, CaRING1 expression is induced by avirulent Xanthomonas campestris pv vesicatoria infection. CaRING1 contains an amino-terminal transmembrane domain and a carboxyl-terminal RING domain. In addition, it displays in vitro E3 ubiquitin ligase activity, and the RING domain is essential for E3 ubiquitin ligase activity in CaRING1. CaRING1 also localizes to the plasma membrane. In pepper plants, virus-induced gene silencing of CaRING1 confers enhanced susceptibility to avirulent X. campestris pv vesicatoria infection, which is accompanied by compromised hypersensitive cell death, reduced expression of PATHOGENESIS-RELATED1, and lowered salicylic acid levels in leaves. Transient expression of CaRING1 in pepper leaves induces cell death and the defense response that requires the E3 ubiquitin ligase activity of CaRING1. By contrast, overexpression of CaRING1 in Arabidopsis (Arabidopsis thaliana) confers enhanced resistance to hemibiotrophic Pseudomonas syringae pv tomato and biotrophic Hyaloperonospora arabidopsidis infections. Taken together, these results suggest that CaRING1 is involved in the induction of cell death and the regulation of ubiquitination during the defense response to microbial pathogens. PMID:21628629

  18. Characterization of the β-Carotene Hydroxylase Gene DSM2 Conferring Drought and Oxidative Stress Resistance by Increasing Xanthophylls and Abscisic Acid Synthesis in Rice1[C][W][OA

    PubMed Central

    Du, Hao; Wang, Nili; Cui, Fei; Li, Xianghua; Xiao, Jinghua; Xiong, Lizhong

    2010-01-01

    Drought is a major limiting factor for crop production. To identify critical genes for drought resistance in rice (Oryza sativa), we screened T-DNA mutants and identified a drought-hypersensitive mutant, dsm2. The mutant phenotype was caused by a T-DNA insertion in a gene encoding a putative β-carotene hydroxylase (BCH). BCH is predicted for the biosynthesis of zeaxanthin, a carotenoid precursor of abscisic acid (ABA). The amounts of zeaxanthin and ABA were significantly reduced in two allelic dsm2 mutants after drought stress compared with the wild type. Under drought stress conditions, the mutant leaves lost water faster than the wild type and the photosynthesis rate, biomass, and grain yield were significantly reduced, whereas malondialdehyde level and stomata aperture were increased in the mutant. The mutant is also hypersensitive to oxidative stresses. The mutant had significantly lower maximal efficiency of photosystem II photochemistry and nonphotochemical quenching capacity than the wild type, indicating photoinhibition in photosystem II and decreased capacity for eliminating excess energy by thermal dissipation. Overexpression of DSM2 in rice resulted in significantly increased resistance to drought and oxidative stresses and increases of the xanthophylls and nonphotochemical quenching. Some stress-related ABA-responsive genes were up-regulated in the overexpression line. DSM2 is a chloroplast protein, and the response of DSM2 to environmental stimuli is distinctive from the other two BCH members in rice. We conclude that the DSM2 gene significantly contributes to control of the xanthophyll cycle and ABA synthesis, both of which play critical roles in the establishment of drought resistance in rice. PMID:20852032

  19. Drought and Salt Stress Tolerance of an Arabidopsis Glutathione S-Transferase U17 Knockout Mutant Are Attributed to the Combined Effect of Glutathione and Abscisic Acid1[C][W][OA

    PubMed Central

    Chen, Jui-Hung; Jiang, Han-Wei; Hsieh, En-Jung; Chen, Hsing-Yu; Chien, Ching-Te; Hsieh, Hsu-Liang; Lin, Tsan-Piao

    2012-01-01

    Although glutathione S-transferases (GSTs) are thought to play major roles in oxidative stress metabolism, little is known about the regulatory functions of GSTs. We have reported that Arabidopsis (Arabidopsis thaliana) GLUTATHIONE S-TRANSFERASE U17 (AtGSTU17; At1g10370) participates in light signaling and might modulate various aspects of development by affecting glutathione (GSH) pools via a coordinated regulation with phytochrome A. Here, we provide further evidence to support a negative role of AtGSTU17 in drought and salt stress tolerance. When AtGSTU17 was mutated, plants were more tolerant to drought and salt stresses compared with wild-type plants. In addition, atgstu17 accumulated higher levels of GSH and abscisic acid (ABA) and exhibited hyposensitivity to ABA during seed germination, smaller stomatal apertures, a lower transpiration rate, better development of primary and lateral root systems, and longer vegetative growth. To explore how atgstu17 accumulated higher ABA content, we grew wild-type plants in the solution containing GSH and found that they accumulated ABA to a higher extent than plants grown in the absence of GSH, and they also exhibited the atgstu17 phenotypes. Wild-type plants treated with GSH also demonstrated more tolerance to drought and salt stresses. Furthermore, the effect of GSH on root patterning and drought tolerance was confirmed by growing the atgstu17 in solution containing l-buthionine-(S,R)-sulfoximine, a specific inhibitor of GSH biosynthesis. In conclusion, the atgstu17 phenotype can be explained by the combined effect of GSH and ABA. We propose a role of AtGSTU17 in adaptive responses to drought and salt stresses by functioning as a negative component of stress-mediated signal transduction pathways. PMID:22095046

  20. The Nuclear Interactor PYL8/RCAR3 of Fagus sylvatica FsPP2C1 Is a Positive Regulator of Abscisic Acid Signaling in Seeds and Stress1[C][W][OA

    PubMed Central

    Saavedra, Xandra; Modrego, Abelardo; Rodríguez, Dolores; González-García, Mary Paz; Sanz, Luis; Nicolás, Gregorio; Lorenzo, Oscar

    2010-01-01

    The functional protein phosphatase type 2C from beechnut (Fagus sylvatica; FsPP2C1) was a negative regulator of abscisic acid (ABA) signaling in seeds. In this report, to get deeper insight on FsPP2C1 function, we aim to identify PP2C-interacting partners. Two closely related members (PYL8/RCAR3 and PYL7/RCAR2) of the Arabidopsis (Arabidopsis thaliana) BetV I family were shown to bind FsPP2C1 in a yeast two-hybrid screening and in an ABA-independent manner. By transient expression of FsPP2C1 and PYL8/RCAR3 in epidermal onion (Allium cepa) cells and agroinfiltration in tobacco (Nicotiana benthamiana) as green fluorescent protein fusion proteins, we obtained evidence supporting the subcellular localization of both proteins mainly in the nucleus and in both the cytosol and the nucleus, respectively. The in planta interaction of both proteins in tobacco cells by bimolecular fluorescence complementation assays resulted in a specific nuclear colocalization of this interaction. Constitutive overexpression of PYL8/RCAR3 confers ABA hypersensitivity in Arabidopsis seeds and, consequently, an enhanced degree of seed dormancy. Additionally, transgenic 35S:PYL8/RCAR3 plants are unable to germinate under low concentrations of mannitol, NaCl, or paclobutrazol, which are not inhibiting conditions to the wild type. In vegetative tissues, Arabidopsis PYL8/RCAR3 transgenic plants show ABA-resistant drought response and a strong inhibition of early root growth. These phenotypes are strengthened at the molecular level with the enhanced induction of several ABA response genes. Both seed and vegetative phenotypes of Arabidopsis 35S:PYL8/RCAR3 plants are opposite those of 35S:FsPP2C1 plants. Finally, double transgenic plants confirm the role of PYL8/RCAR3 by antagonizing FsPP2C1 function and demonstrating that PYL8/RCAR3 positively regulates ABA signaling during germination and abiotic stress responses. PMID:19889877

  1. Low Red/Far-Red Ratios Reduce Arabidopsis Resistance to Botrytis cinerea and Jasmonate Responses via a COI1-JAZ10-Dependent, Salicylic Acid-Independent Mechanism1[C][W][OA

    PubMed Central

    Cerrudo, Ignacio; Keller, Mercedes M.; Cargnel, Miriam D.; Demkura, Patricia V.; de Wit, Mieke; Patitucci, Micaela S.; Pierik, Ronald; Pieterse, Corné M.J.; Ballaré, Carlos L.

    2012-01-01

    Light is an important modulator of plant immune responses. Here, we show that inactivation of the photoreceptor phytochrome B (phyB) by a low red/far-red ratio (R:FR), which is a signal of competition in plant canopies, down-regulates the expression of defense markers induced by the necrotrophic fungus Botrytis cinerea, including the genes that encode the transcription factor ETHYLENE RESPONSE FACTOR1 (ERF1) and the plant defensin PLANT DEFENSIN1.2 (PDF1.2). This effect of low R:FR correlated with a reduced sensitivity to jasmonate (JA), thus resembling the antagonistic effects of salicylic acid (SA) on JA responses. Low R:FR failed to depress PDF1.2 mRNA levels in a transgenic line in which PDF1.2 transcription was up-regulated by constitutive expression of ERF1 in a coronatine insensitive1 (coi1) mutant background (35S::ERF1/coi1). These results suggest that the low R:FR effect, in contrast to the SA effect, requires a functional SCFCOI1-JASMONATE ZIM-DOMAIN (JAZ) JA receptor module. Furthermore, the effect of low R:FR depressing the JA response was conserved in mutants impaired in SA signaling (sid2-1 and npr1-1). Plant exposure to low R:FR ratios and the phyB mutation markedly increased plant susceptibility to B. cinerea; the effect of low R:FR was (1) independent of the activation of the shade-avoidance syndrome, (2) conserved in the sid2-1 and npr1-1 mutants, and (3) absent in two RNA interference lines disrupted for the expression of the JAZ10 gene. Collectively, our results suggest that low R:FR ratios depress Arabidopsis (Arabidopsis thaliana) immune responses against necrotrophic microorganisms via a SA-independent mechanism that requires the JAZ10 transcriptional repressor and that this effect may increase plant susceptibility to fungal infection in dense canopies. PMID:22371506

  2. Activation of TRPC channels contributes to OA-NO2-induced responses in guinea-pig dorsal root ganglion neurons

    PubMed Central

    Zhang, Xiulin; Beckel, Jonathan M; Daugherty, Stephanie L; Wang, Ting; Woodcock, Stephen R; Freeman, Bruce A; de Groat, William C

    2014-01-01

    Effects of nitro-oleic acid (OA-NO2) on TRP channels were examined in guinea-pig dissociated dorsal root ganglia (DRG) neurons using calcium imaging and patch clamp techniques. OA-NO2 increased intracellular Ca2+ in 60–80% DRG neurons. 1-Oleoyl-2acetyl-sn-glycerol (OAG), a TRPC agonist, elicited responses in 36% of OA-NO2-sensitive neurons while capsaicin (TRPV1 agonist) or allyl-isothiocyanate (AITC, TRPA1 agonist) elicited responses in only 16% and 10%, respectively, of these neurons. A TRPV1 antagonist (diarylpiperazine, 5 μm) in combination with a TRPA1 antagonist (HC-030031, 30 μm) did not change the amplitude of the Ca2+ transients or percentage of neurons responding to OA-NO2; however, a reducing agent DTT (50 mm) or La3+ (50 μm) completely abolished OA-NO2 responses. OA-NO2 also induced a transient inward current associated with a membrane depolarization followed by a prolonged outward current and hyperpolarization in 80% of neurons. The reversal potentials of inward and outward currents were approximately −20 mV and −60 mV, respectively. Inward current was reduced when extracellular Na+ was absent, but unchanged by niflumic acid (100 μm), a Cl− channel blocker. Outward current was abolished in the absence of extracellular Ca2+ or a combination of two Ca2+-activated K+ channel blockers (iberiotoxin, 100 nm and apamin, 1 μm). BTP2 (1 or 10 μm), a broad spectrum TRPC antagonist, or La3+ (50 μm) completely abolished OA-NO2 currents. RT-PCR performed on mRNA extracted from DRGs revealed the expression of all seven subtypes of TRPC channels. These results support the hypothesis that OA-NO2 activates TRPC channels other than the TRPV1 and TRPA1 channels already known to be targets in rat and mouse sensory neurons and challenge the prevailing view that electrophilic compounds act specifically on TRPA1 or TRPV1 channels. The modulation of sensory neuron excitability via actions on multiple TRP channels can contribute to the anti-inflammatory effect

  3. PRP in OA knee – update, current confusions and future options

    PubMed Central

    Dhillon, Mandeep S.; Patel, Sandeep; John, Rakesh

    2017-01-01

    Positive results have been uniformly observed by various researchers for platelet-rich plasma (PRP) in early osteoarthritis (OA) knee in the past few years. PRP has clearly demonstrated its supremacy in comparison to hyaluronic acid (HA) and placebo in various clinical trials and is undoubtedly the best option available for symptomatic treatment in early OA. The release of growth factors from PRP occurs immediately and lasts for around three weeks and the clinical effect tends to wane down by the end of the year. Prolonged and sustained release of growth factors from platelets could possibly help in much better biological healing and sustained clinical effects. PRP in combination with biocompatible carriers could be one way of achieving this. Gelatin hydrogel PRP and chitosan PRP seem to be promising based on early in vitro studies and animal studies. PRP in combination with hyaluronic acid also seems to be additive. This article intends to discuss the present status of the PRP, confusions surrounding its use, upcoming trends and ideas for improvising PRP for use early OA knees based on available evidence. PMID:28322719

  4. Inhibition of the OAS/RNase L pathway by viruses.

    PubMed

    Drappier, Melissa; Michiels, Thomas

    2015-12-01

    The OAS/RNase L system was one of the first characterized interferon effector pathways. It relies on the synthesis, by oligoadenylate synthetases (OAS), of short oligonucleotides that act as second messengers to activate the latent cellular RNase L. Viruses have developed diverse strategies to escape its antiviral effects. This underscores the importance of the OAS/RNase L pathway in antiviral defenses. Viral proteins such as the NS1 protein of Influenza virus A act upstream of the pathway while other viral proteins such as Theiler's virus L* protein act downstream. The diversity of escape strategies used by viruses likely stems from their relative susceptibility to OAS/RNase L and other antiviral pathways, which may depend on their host and cellular tropism.

  5. Oxalic acid alleviates chilling injury in peach fruit by regulating energy metabolism and fatty acid contents.

    PubMed

    Jin, Peng; Zhu, Hong; Wang, Lei; Shan, Timin; Zheng, Yonghua

    2014-10-15

    The effects of postharvest oxalic acid (OA) treatment on chilling injury, energy metabolism and membrane fatty acid content in 'Baifeng' peach fruit stored at 0°C were investigated. Internal browning was significantly reduced by OA treatment in peaches. OA treatment markedly inhibited the increase of ion leakage and the accumulation of malondialdehyde. Meanwhile, OA significantly increased the contents of adenosine triphosphate and energy charge in peach fruit. Enzyme activities of energy metabolism including H(+)-adenosine triphosphatase, Ca(2+)-adenosine triphosphatase, succinic dehydrogenase and cytochrome C oxidase were markedly enhanced by OA treatment. The ratio of unsaturated/saturated fatty acid in OA-treated fruit was significantly higher than that in control fruit. These results suggest that the alleviation in chilling injury by OA may be due to enhanced enzyme activities related to energy metabolism and higher levels of energy status and unsaturated/saturated fatty acid ratio.

  6. Acute Cardiotoxicity Evaluation of the Marine Biotoxins OA, DTX-1 and YTX

    PubMed Central

    Ferreiro, Sara F.; Carrera, Cristina; Vilariño, Natalia; Louzao, M. Carmen; Santamarina, Germán; Cantalapiedra, Antonio G.; Botana, Luis M.

    2015-01-01

    Phycotoxins are marine toxins produced by phytoplankton that can get accumulated in filter feeding shellfish. Human intoxication episodes occur due to contaminated seafood consumption. Okadaic acid (OA) and dynophysistoxins (DTXs) are phycotoxins responsible for a severe gastrointestinal syndrome called diarrheic shellfish poisoning (DSP). Yessotoxins (YTXs) are marine toxins initially included in the DSP class but currently classified as a separated group. Food safety authorities from several countries have regulated the content of DSPs and YTXs in shellfish to protect human health. In mice, OA and YTX have been associated with ultrastructural heart damage in vivo. Therefore, this study explored the potential of OA, DTX-1 and YTX to cause acute heart toxicity. Cardiotoxicity was evaluated in vitro by measuring hERG (human èter-a-go-go gene) channel activity and in vivo using electrocardiogram (ECG) recordings and cardiac damage biomarkers. The results demonstrated that these toxins do not exert acute effects on hERG channel activity. Additionally, in vivo experiments showed that these compounds do not alter cardiac biomarkers and ECG in rats acutely. Despite the ultrastructural damage to the heart reported for these toxins, no acute alterations of heart function have been detected in vivo, suggesting a functional compensation in the short term. PMID:25826053

  7. A homolog of the human Hermansky-Pudluck syndrome-5 (HPS5) gene is responsible for the oa larval translucent mutants in the silkworm, Bombyx mori.

    PubMed

    Fujii, T; Banno, Y; Abe, H; Katsuma, S; Shimada, T

    2012-12-01

    Normally, many granules containing uric acid accumulate in the larval integument of the silkworm, Bombyx mori. These uric acid granules cause the wild-type larval integument to be white or opaque, and the absence of these granules results in a translucent integument. Although about 30 B. mori loci governing larval translucency have been mapped, most have not been molecularly identified yet. Here, based on a structural analysis of a deletion of chromosome 14 that included the oa (aojyuku translucent) locus, we concluded that the BmHPS5 encoding a Bombyx homolog of the HPS5 subunit of biogenesis of lysosome-related organelles complex-2 is the candidate for the oa locus. Nucleotide sequence analyses of cDNAs and genomic DNAs in three mutant strains, each of which were homozygous for the respective allele of the oa locus (oa, oa ( 2 ), and oa ( v )), revealed that each mutant strain has a frame shift or a premature stop codon (caused by deletion or nonsense mutation, respectively) in the BmHPS5 gene. Our findings indicate that some genes that cause the translucent phenotype in Bombyx, some HPS-associated genes in humans, and some genes that cause mutant eye color phenotypes in Drosophila are homologous and participate in an evolutionarily conserved mechanism that leads to biogenesis of lysosome-related organelles.

  8. D-erythroascorbic acid: Its preparations, chemistry, and metabolism (fungi and plants)

    SciTech Connect

    Loewus, F.A. . Inst. of Biological Chemistry); Seib, P.A. . Dept. of Grain Science and Industry)

    1990-01-01

    Sclerotinia sclerotiorum contains D-erythroascorbic acid (EAA) and a closely related reducing acid, possibly the open-chain form of EAA. The organism cleaves one of these products or possibly both to yield OA and D-glyceric acid. The OA is rapidly secreted into the medium. An analogy can be made between AA-linked OA biosynthesis in higher plants and EAA-linked OA biosynthesis in fungi as exemplified by S. sclerotiorum.

  9. Activation of RNase L is dependent on OAS3 expression during infection with diverse human viruses

    PubMed Central

    Li, Yize; Banerjee, Shuvojit; Wang, Yuyan; Goldstein, Stephen A.; Dong, Beihua; Gaughan, Christina; Silverman, Robert H.; Weiss, Susan R.

    2016-01-01

    The 2′,5′-oligoadenylate (2-5A) synthetase (OAS)–RNase L system is an IFN-induced antiviral pathway. RNase L activity depends on 2-5A, synthesized by OAS. Although all three enzymatically active OAS proteins in humans—OAS1, OAS2, and OAS3—synthesize 2-5A upon binding dsRNA, it is unclear which are responsible for RNase L activation during viral infection. We used clustered regularly interspaced short palindromic repeats (CRISPR)–CRISPR-associated protein-9 nuclease (Cas9) technology to engineer human A549-derived cell lines in which each of the OAS genes or RNase L is knocked out. Upon transfection with poly(rI):poly(rC), a synthetic surrogate for viral dsRNA, or infection with each of four viruses from different groups (West Nile virus, Sindbis virus, influenza virus, or vaccinia virus), OAS1-KO and OAS2-KO cells synthesized amounts of 2-5A similar to those synthesized in parental wild-type cells, causing RNase L activation as assessed by rRNA degradation. In contrast, OAS3-KO cells synthesized minimal 2-5A, and rRNA remained intact, similar to infected RNase L-KO cells. All four viruses replicated to higher titers in OAS3-KO or RNase L-KO A549 cells than in parental, OAS1-KO, or OAS2-KO cells, demonstrating the antiviral effects of OAS3. OAS3 displayed a higher affinity for dsRNA in intact cells than either OAS1 or OAS2, consistent with its dominant role in RNase L activation. Finally, the requirement for OAS3 as the major OAS isoform responsible for RNase L activation was not restricted to A549 cells, because OAS3-KO cells derived from two other human cell lines also were deficient in RNase L activation. PMID:26858407

  10. Activation of RNase L is dependent on OAS3 expression during infection with diverse human viruses.

    PubMed

    Li, Yize; Banerjee, Shuvojit; Wang, Yuyan; Goldstein, Stephen A; Dong, Beihua; Gaughan, Christina; Silverman, Robert H; Weiss, Susan R

    2016-02-23

    The 2',5'-oligoadenylate (2-5A) synthetase (OAS)-RNase L system is an IFN-induced antiviral pathway. RNase L activity depends on 2-5A, synthesized by OAS. Although all three enzymatically active OAS proteins in humans--OAS1, OAS2, and OAS3--synthesize 2-5A upon binding dsRNA, it is unclear which are responsible for RNase L activation during viral infection. We used clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein-9 nuclease (Cas9) technology to engineer human A549-derived cell lines in which each of the OAS genes or RNase L is knocked out. Upon transfection with poly(rI):poly(rC), a synthetic surrogate for viral dsRNA, or infection with each of four viruses from different groups (West Nile virus, Sindbis virus, influenza virus, or vaccinia virus), OAS1-KO and OAS2-KO cells synthesized amounts of 2-5A similar to those synthesized in parental wild-type cells, causing RNase L activation as assessed by rRNA degradation. In contrast, OAS3-KO cells synthesized minimal 2-5A, and rRNA remained intact, similar to infected RNase L-KO cells. All four viruses replicated to higher titers in OAS3-KO or RNase L-KO A549 cells than in parental, OAS1-KO, or OAS2-KO cells, demonstrating the antiviral effects of OAS3. OAS3 displayed a higher affinity for dsRNA in intact cells than either OAS1 or OAS2, consistent with its dominant role in RNase L activation. Finally, the requirement for OAS3 as the major OAS isoform responsible for RNase L activation was not restricted to A549 cells, because OAS3-KO cells derived from two other human cell lines also were deficient in RNase L activation.

  11. α-Lactalbumin:Oleic Acid Complex Spontaneously Delivers Oleic Acid to Artificial and Erythrocyte Membranes.

    PubMed

    Wen, Hanzhen; Strømland, Øyvind; Halskau, Øyvind

    2015-09-25

    Human α-lactalbumin made lethal to tumor cells (HAMLET) is a tumoricidal complex consisting of human α-lactalbumin and multiple oleic acids (OAs). OA has been shown to play a key role in the activity of HAMLET and its related complexes, generally known as protein-fatty acid (PFA) complexes. In contrast to what is known about the fate of the protein component of such complexes, information about what happens to OA during their action is still lacking. We monitored the membrane, OA and protein components of bovine α-lactalbumin complexed with OA (BLAOA; a HAMLET-like substance) and how they associate with each other. Using ultracentrifugation, we found that the OA and lipid components follow each other closely. We then firmly identify a transfer of OA from BLAOA to both artificial and erythrocyte membranes, indicating that natural cells respond similarly to BLAOA treatment as artificial membranes. Uncomplexed OA is unable to similarly affect membranes at the conditions tested, even at elevated concentrations. Thus, BLAOA can spontaneously transfer OA to a lipid membrane. After the interaction with the membrane, the protein is likely to have lost most or all of its OA. We suggest a mechanism for passive import of mainly uncomplexed protein into cells, using existing models for OA's effect on membranes. Our results are consistent with a membrane destabilization mediated predominantly by OA insertion being a significant contribution to PFA cytotoxicity.

  12. Exchangeable hydrogen explains the pH of spodosol Oa horizons

    USGS Publications Warehouse

    Ross, D.S.; David, M.B.; Lawrence, G.B.; Bartlett, R.J.

    1996-01-01

    The chemistry of extremely acid Oa horizons does not conform to traditional pH, Al, and base saturation relationships. Results from two separate studies of northeastern U.S. forested soils were used to investigate relationships between pH in water or dilute salt solutions and other soil characteristics. In Oa horizons with pH below 4, soil pH in dilute CaCl2 solution was correlated with exchangeable H+ measured either by titration (r = -0.88, P = 0.0001, n = 142) or by electrode (r = -0.89, P = 0.0001, n = 45). Exchangeable H+ expressed as a percentage of the cation-exchange capacity (CEC) was linear with pH and showed similar slopes for data from both studies. For all samples, pHw = 4.21 - 1.80 x H+/CEC (R2 = 0.69, n = 194). The reciprocal of the H+/CEC ratio is base saturation with Al added to the bases. Because of the low pH, exchangeable Al does not appear to behave as an acid. Exchangeable H+ remains an operationally defined quantity because of the difficulty in separating exchange and hydrolysis reactions. In a variety of neutral-salt extractants, concentration of H+ were correlated with 0.1 M BaCl2-exchangeable H+ (r > 0.91, P = 0.0001, n = 26) regardless of the strength of the extract. Nine successive extractions with 0.33 mM CaCl2 removed more H+ than was removed by single batch extractions with either 1 M KCl or 0.1 M BaCl2 (average H+ of 70, 43, and 49 mmol kg-1, respectively for 26 samples). The data showed little difference in the chemical behavior of Oa horizons from a variety of geographical sites and vegetation types.

  13. BOREAS TF-1 SSA-OA Soil Characteristics Data

    NASA Technical Reports Server (NTRS)

    Black, T. Andrew; Chen, Z; Nesic, Z.; Hall, Forrest G. (Editor); Papagno, Andrea (Editor)

    2000-01-01

    The BOREAS TF-1 team collected several data sets in support of its efforts to characterize and interpret soil information at the SSA-OA tower site in 1994 as part of BOREAS. Data sets collected include soil respiration, temperature, moisture, and gravimetric data. The data are stored in tabular ASCII format.

  14. Oleanolic acid alters bile acid metabolism and produces cholestatic liver injury in mice

    SciTech Connect

    Liu, Jie; Lu, Yuan-Fu; Zhang, Youcai; Wu, Kai Connie; Fan, Fang; Klaassen, Curtis D.

    2013-11-01

    Oleanolic acid (OA) is a triterpenoids that exists widely in plants. OA is effective in protecting against hepatotoxicants. Whereas a low dose of OA is hepatoprotective, higher doses and longer-term use of OA produce liver injury. This study characterized OA-induced liver injury in mice. Adult C57BL/6 mice were given OA at doses of 0, 22.5, 45, 90, and 135 mg/kg, s.c., daily for 5 days, and liver injury was observed at doses of 90 mg/kg and above, as evidenced by increases in serum activities of alanine aminotransferase and alkaline phosphatase, increases in serum total bilirubin, as well as by liver histopathology. OA-induced cholestatic liver injury was further evidenced by marked increases of both unconjugated and conjugated bile acids (BAs) in serum. Gene and protein expression analysis suggested that livers of OA-treated mice had adaptive responses to prevent BA accumulation by suppressing BA biosynthetic enzyme genes (Cyp7a1, 8b1, 27a1, and 7b1); lowering BA uptake transporters (Ntcp and Oatp1b2); and increasing a BA efflux transporter (Ostβ). OA increased the expression of Nrf2 and its target gene, Nqo1, but decreased the expression of AhR, CAR and PPARα along with their target genes, Cyp1a2, Cyp2b10 and Cyp4a10. OA had minimal effects on PXR and Cyp3a11. Taken together, the present study characterized OA-induced liver injury, which is associated with altered BA homeostasis, and alerts its toxicity potential. - Highlights: • Oleanolic acid at higher doses and long-term use may produce liver injury. • Oleanolic acid increased serum ALT, ALP, bilirubin and bile acid concentrations. • OA produced feathery degeneration, inflammation and cell death in the liver. • OA altered bile acid homeostasis, affecting bile acid synthesis and transport.

  15. Bitterness in Almonds1[C][OA

    PubMed Central

    Sánchez-Pérez, Raquel; Jørgensen, Kirsten; Olsen, Carl Erik; Dicenta, Federico; Møller, Birger Lindberg

    2008-01-01

    Bitterness in almond (Prunus dulcis) is determined by the content of the cyanogenic diglucoside amygdalin. The ability to synthesize and degrade prunasin and amygdalin in the almond kernel was studied throughout the growth season using four different genotypes for bitterness. Liquid chromatography-mass spectrometry analyses showed a specific developmentally dependent accumulation of prunasin in the tegument of the bitter genotype. The prunasin level decreased concomitant with the initiation of amygdalin accumulation in the cotyledons of the bitter genotype. By administration of radiolabeled phenylalanine, the tegument was identified as a specific site of synthesis of prunasin in all four genotypes. A major difference between sweet and bitter genotypes was observed upon staining of thin sections of teguments and cotyledons for β-glucosidase activity using Fast Blue BB salt. In the sweet genotype, the inner epidermis in the tegument facing the nucellus was rich in cytoplasmic and vacuolar localized β-glucosidase activity, whereas in the bitter cultivar, the β-glucosidase activity in this cell layer was low. These combined data show that in the bitter genotype, prunasin synthesized in the tegument is transported into the cotyledon via the transfer cells and converted into amygdalin in the developing almond seed, whereas in the sweet genotype, amygdalin formation is prevented because the prunasin is degraded upon passage of the β-glucosidase-rich cell layer in the inner epidermis of the tegument. The prunasin turnover may offer a buffer supply of ammonia, aspartic acid, and asparagine enabling the plants to balance the supply of nitrogen to the developing cotyledons. PMID:18192442

  16. Baseline Vitamin D Status is Predictive of Longitudinal Change in Tibial BMD in Knee Osteoarthritis (OA)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With its lack of effective treatment and high prevalence, the public health impact of OA is substantial. Peri-articular bone in OA can be evaluated with the medial:lateral tibial BMD ratio (M:L BMD) obtained from dual x-ray absorptiometry (DXA). Higher M:L BMD is associated with medial OA features...

  17. 41 CFR 102-85.25 - What is the basic principle governing OAs?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What is the basic principle governing OAs? 102-85.25 Section 102-85.25 Public Contracts and Property Management Federal... governing OAs? The basic principle governing OAs is to adopt the private sector practice of capturing in...

  18. Integration of the B-52G Offensive Avionics System (OAS) with the Global Positioning System (GPS)

    NASA Astrophysics Data System (ADS)

    Foote, A. L.; Pluntze, S. C.

    Integration of the B-52G OAS with the GPS has been accomplished by modification of existing OAS software. GPS derived position and velocity data are used to enhance the quality of the OAS inertial and dead reckoning navigation systems. The engineering design and the software development process used to implement this design are presented.

  19. D-erythroascorbic acid: Its preparations, chemistry, and metabolism (fungi and plants). Second year [annual] report, [May 23, 1988--May 22, 1990

    SciTech Connect

    Loewus, F.A.; Seib, P.A.

    1990-12-31

    Sclerotinia sclerotiorum contains D-erythroascorbic acid (EAA) and a closely related reducing acid, possibly the open-chain form of EAA. The organism cleaves one of these products or possibly both to yield OA and D-glyceric acid. The OA is rapidly secreted into the medium. An analogy can be made between AA-linked OA biosynthesis in higher plants and EAA-linked OA biosynthesis in fungi as exemplified by S. sclerotiorum.

  20. Welcome to volume 3 of Future Science OA.

    PubMed

    Lake, Francesca

    2017-03-01

    Happy New Year to all of our readers! Welcome to volume 3 of Future Science OA. 2016 was another excellent year, with us receiving some superb content for publication, and our becoming indexed on both Chemical Abstracts and the Emerging Sources Citation Index, meaning our content now appears on Web of Science. We thank our readers, reviewers, authors and Editorial Board members for their continued support, and look forward to working with everyone in 2017.

  1. NF-κB Signaling: Multiple angles to target OA

    PubMed Central

    Marcu, Kenneth B.; Otero, Miguel; Olivotto, Eleonora; Borzi, Rosa Maria; Goldring, Mary B.

    2011-01-01

    In the context of OA disease, NF-κB transcription factors can be triggered by a host of stress-related stimuli including pro-inflammatory cytokines, excessive mechanical stress and ECM degradation products. Activated NF-κB regulates the expression of many cytokines and chemokines, adhesion molecules, inflammatory mediators, and several matrix degrading enzymes. NF-κB also influences the regulated accumulation and remodeling of ECM proteins and has indirect positive effects on downstream regulators of terminal chondrocyte differentiation (including β-catenin and Runx2). Although driven partly by pro-inflammatory and stress-related factors, OA pathogenesis also involves a “loss of maturational arrest” that inappropriately pushes chondrocytes towards a more differentiated, hypertrophic-like state. Growing evidence points to NF-κB signaling as not only playing a central role in the pro-inflammatory stress-related responses of chondrocytes to extra- and intra-cellular insults, but also in the control of their differentiation program. Thus unlike other signaling pathways the NF-κB activating kinases are potential therapeutic OA targets for multiple reasons. Targeted strategies to prevent unwanted NF-κB activation in this context, which do not cause side effects on other proteins or signaling pathways, need to be focused on the use of highly specific drug modalities, siRNAs or other biological inhibitors that are targeted to the activating NF-κB kinases IKKα or IKKβ or specific activating canonical NF-κB subunits. However, work remains in its infancy to evaluate the effects of efficacious, targeted NF-κB inhibitors in animal models of OA disease in vivo and to also target these strategies only to affected cartilage and joints to avoid other undesirable systemic effects. PMID:20199390

  2. Welcome to volume 3 of Future Science OA

    PubMed Central

    Lake, Francesca

    2017-01-01

    Happy New Year to all of our readers! Welcome to volume 3 of Future Science OA. 2016 was another excellent year, with us receiving some superb content for publication, and our becoming indexed on both Chemical Abstracts and the Emerging Sources Citation Index, meaning our content now appears on Web of Science. We thank our readers, reviewers, authors and Editorial Board members for their continued support, and look forward to working with everyone in 2017. PMID:28344821

  3. Absolute Quantification of Lipophilic Shellfish Toxins by Quantitative Nuclear Magnetic Resonance Using Removable Internal Reference Substance with SI Traceability.

    PubMed

    Kato, Tsuyoshi; Saito, Maki; Nagae, Mika; Fujita, Kazuhiro; Watai, Masatoshi; Igarashi, Tomoji; Yasumoto, Takeshi; Inagaki, Minoru

    2016-01-01

    Okadaic acid (OA), a lipophilic shellfish toxin, was accurately quantified using quantitative nuclear magnetic resonance with internal standards for the development of an authentic reference standard. Pyridine and the residual proton in methanol-d4 were used as removable internal standards to limit any contamination. They were calibrated based on a maleic acid certified reference material. Thus, the concentration of OA was traceable to the SI units through accurate quantitative NMR with an internal reference substance. Signals from the protons on the oxygenated and unsaturated carbons of OA were used for quantification. A reasonable accuracy was obtained by integrating between the lower and upper (13)C satellite signal range when more than 4 mg of OA was used. The best-determined purity was 97.4% (0.16% RSD) when 20 mg of OA was used. Dinophysistoxin-1, a methylated analog of OA having an almost identical spectrum, was also quantified by using the same methodology.

  4. Hydroxy-oleic acid, but not oleic acid, inhibits vascular responsiveness in isolated aortic tissue

    EPA Science Inventory

    Oleic acid (OA) and other fatty acids can become abundant in circulation after air pollution exposure as endogenously released lipolysis byproducts or by entering the body as a component of air pollution. Vascular damage has been observed with OA infusion, but it is not yet estab...

  5. Mitochondrial localization of the OAS1 p46 isoform associated with a common single nucleotide polymorphism

    PubMed Central

    2014-01-01

    Background The expression of 2′-5′-Oligoadenylate synthetases (OASs) is induced by type 1 Interferons (IFNs) in response to viral infection. The OAS proteins have a unique ability to produce 2′-5′ Oligoadenylates, which bind and activate the ribonuclease RNase L. The RNase L degrades cellular RNAs which in turn inhibits protein translation and induces apoptosis. Several single nucleotide polymorphisms (SNPs) in the OAS1 gene have been associated with disease. We have investigated the functional effect of two common SNPs in the OAS1 gene. The SNP rs10774671 affects splicing to one of the exons in the OAS1 gene giving rise to differential expression of the OAS1 isoforms, and the SNP rs1131454 (former rs3741981) resides in exon 3 giving rise to OAS1 isoforms with either a Glycine or a Serine at position 162 in the core OAS unit. Results We have used three human cell lines with different genotypes in the OAS1 SNP rs10774671, HeLa cells with the AA genotype, HT1080 cells with AG, and Daudi cells with GG. The main OAS1 isoform expressed in Daudi and HT1080 cells was p46, and the main OAS1 isoform expressed in HeLa cells was p42. In addition, low levels of the OAS1 p52 mRNA was detected in HeLa cells and p48 mRNA in Daudi cells, and trace amounts of p44a mRNA were detected in the three cell lines treated with type 1 interferon. We show that the OAS1 p46 isoform was localized in the mitochondria in Daudi cells, whereas the OAS1 isoforms in HeLa cells were primarily localized in cytoplasmic vacuoles/lysosomes. By using recombinantly expressed OAS1 mutant proteins, we found that the OAS1 SNP rs1131454 (former rs3741981) did not affect the enzymatic OAS1 activity. Conclusions The SNP rs10774671 determines differential expression of the OAS1 isoforms. In Daudi and HT1080 cells the p46 isoform is the most abundantly expressed isoform associated with the G allele, whereas in HeLa cells the most abundantly expressed isoform is p42 associated with the A allele. The SNP rs

  6. Influence of Oleic Acid on Rumen Fermentation and Fatty Acid Formation In Vitro

    PubMed Central

    Tang, Shaoxun; Guan, Leluo; He, Zhixiong; Guan, Yongjuan; Tan, Zhiliang; Han, Xuefeng; Zhou, Chuanshe; Kang, Jinhe; Wang, Min

    2016-01-01

    A series of batch cultures were conducted to investigate the effects of oleic acid (OA) on in vitro ruminal dry matter degradability (IVDMD), gas production, methane (CH4) and hydrogen (H2) production, and proportion of fatty acids. Rumen fluid was collected from fistulated goats, diluted with incubation buffer, and then incubated with 500 mg Leymus chinensis meal supplemented with different amounts of OA (0, 20, 40, and 60 mg for the CON, OA20, OA40 and OA60 groups, respectively). Incubation was carried out anaerobically at 39°C for 48 h, and the samples were taken at 12, 24 and 48 h and subjected to laboratory analysis. Supplementation of OA decreased IVDMD, the cumulative gas production, theoretical maximum of gas production and CH4 production, but increased H2 production. However, no effect was observed on any parameters of rumen fermentation (pH, ammonia, production of acetate, propionate and butyrate and total volatile fatty acid production). The concentrations of some beneficial fatty acids, such as cis monounsaturated fatty acids and conjugated linoleic acid (CLA) were higher (P < 0.05) from OA groups than those from the control group at 12 h incubation. In summary, these results suggest that the OA supplementation in diet can reduce methane production and increase the amount of some beneficial fatty acids in vitro. PMID:27299526

  7. Downstream extraction process development for recovery of organic acids from a fermentation broth.

    PubMed

    Bekatorou, Argyro; Dima, Agapi; Tsafrakidou, Panagiotia; Boura, Konstantina; Lappa, Katerina; Kandylis, Panagiotis; Pissaridi, Katerina; Kanellaki, Maria; Koutinas, Athanasios A

    2016-11-01

    The present study focused on organic acids (OAs) recovery from an acidogenic fermentation broth, which is the main problem regarding the use of OAs for production of ester-based new generation biofuels or other applications. Specifically, 10 solvents were evaluated for OAs recovery from aqueous media and fermentation broths. The effects of pH, solvent/OAs solution ratios and application of successive extractions were studied. The 1:1 solvent/OAs ratio showed the best recovery rates in most cases. Butyric and isobutyric acids showed the highest recovery rates (80-90%), while lactic, succinic, and acetic acids were poorly recovered (up to 45%). The OAs recovery was significantly improved by successive 10-min extractions. Alcohols presented the best extraction performance. The process using repeated extractions with 3-methyl-1-butanol led to the highest OAs recovery. However, 1-butanol can be considered as the most cost-effective option taking into account its price and availability.

  8. Oleic acid is a key cytotoxic component of HAMLET-like complexes.

    PubMed

    Permyakov, Sergei E; Knyazeva, Ekaterina L; Khasanova, Leysan M; Fadeev, Roman S; Zhadan, Andrei P; Roche-Hakansson, Hazeline; Håkansson, Anders P; Akatov, Vladimir S; Permyakov, Eugene A

    2012-01-01

    HAMLET is a complex of α-lactalbumin (α-LA) with oleic acid (OA) that selectively kills tumor cells and Streptococcus pneumoniae. To assess the contribution of the proteinaceous component to cytotoxicity of HAMLET, OA complexes with proteins structurally and functionally distinct from α-LA were prepared. Similar to HAMLET, the OA complexes with bovine β-lactoglobulin (bLG) and pike parvalbumin (pPA) (bLG-OA-45 and pPA-OA-45, respectively) induced S. pneumoniae D39 cell death. The activation mechanisms of S. pneumoniae death for these complexes were analogous to those for HAMLET, and the cytotoxicity of the complexes increased with OA content in the preparations. The half-maximal inhibitory concentration for HEp-2 cells linearly decreased with rise in OA content in the preparations, and OA concentration in the preparations causing HEp-2 cell death was close to the cytotoxicity of OA alone. Hence, the cytotoxic action of these complexes against HEp-2 cells is induced mostly by OA. Thermal stabilization of bLG upon association with OA implies that cytotoxicity of bLG-OA-45 complex cannot be ascribed to molten globule-like conformation of the protein component. Overall, the proteinaceous component of HAMLET-like complexes studied is not a prerequisite for their activity; the cytotoxicity of these complexes is mostly due to the action of OA.

  9. Heat capacities and entropies of Mg2SiOa, Mn2SiOa, and Co2SiOa between 5 and 380 K

    USGS Publications Warehouse

    Robie, Richard A.; Hemingway, Bruch S.; Takei, Humihiko

    1982-01-01

    whereas the shoulder near 12 K corresponds to the change from the collinear to a canted spin structure. Our calorimetric values for the antiferromagnetic-paramagnetictr ansition temperature (N6el Temperature) are in excellent agreement with those obtained by powder magnetic susceptibility measurements, 49t2 K and 5015 K for co2Sioa and Mn2Sioa respectively. The thermal Debye temperature, 0$, of Mg2Sioa calculated from our c$ measurements between 6.3 and 13.8 K is 768+15 K and agrees well with the elastic vaiue ofi of 758 K based on the mean sound velocity calculated from the room temperature elastic stiffness constants (ci:) of Graham and Barsch. At 298.15K (25"c) the molar heat capacitiesa re 118.6,1 28.7, and 133.4J /(mol . K) and the molar entropiesa re 94.11-r0.101, 55.910.4a nd,1 42.6-+0.J2l (mol . K) respectivelyf or Mg2SiO4M, n2SiOaa, nd Co2SiOa.

  10. Activation of the 2-5OAS/RNase L pathway in CVB1 or HAV/18f infected FRhK-4 cells does not require induction of OAS1 or OAS2 expression

    SciTech Connect

    Kulka, Michael; Calvo, Mona S.; Ngo, Diana T.; Wales, Samantha Q.; Goswami, Biswendu B.

    2009-05-25

    The latent, constitutively expressed protein RNase L is activated in coxsackievirus and HAV strain 18f infected FRhK-4 cells. Endogenous oligoadenylate synthetase (OAS) from uninfected and virus infected cell extracts synthesizes active forms of the triphosphorylated 2-5A oligomer (the only known activator of RNase L) in vitro and endogenous 2-5A is detected in infected cell extracts. However, only the largest OAS isoform, OAS3, is readily detected throughout the time course of infection. While IFNbeta treatment results in an increase in the level of all three OAS isoforms in FRhK-4 cells, IFNbeta pretreatment does not affect the temporal onset or enhancement of RNase L activity nor inhibit virus replication. Our results indicate that CVB1 and HAV/18f activate the 2-5OAS/RNase L pathway in FRhK-4 cells during permissive infection through endogenous levels of OAS, but contrary to that reported for some picornaviruses, CVB1 and HAV/18f replication is insensitive to this activated antiviral pathway.

  11. 15 CFR 742.17 - Exports of firearms to OAS member countries.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... activities as drug trafficking, terrorism, and transnational organized crime. (c) Contract sanctity. Contract..., terrorism, and transnational organized crime. (e) OAS member countries to which firearms controls under...

  12. 15 CFR 742.17 - Exports of firearms to OAS member countries.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... activities as drug trafficking, terrorism, and transnational organized crime. (c) Contract sanctity. Contract..., terrorism, and transnational organized crime. (e) OAS member countries to which firearms controls under...

  13. 15 CFR 742.17 - Exports of firearms to OAS member countries.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... activities as drug trafficking, terrorism, and transnational organized crime. (c) Contract sanctity. Contract..., terrorism, and transnational organized crime. (e) OAS member countries to which firearms controls under...

  14. Inflammation and Joint Tissue Interactions in OA: Implications for Potential Therapeutic Approaches

    PubMed Central

    Rainbow, Roshni; Ren, Weiping; Zeng, Li

    2012-01-01

    It is increasingly recognized that the pathogenesis of cartilage degradation in osteoarthritis (OA) is multifactorial and involves the interactions between cartilage and its surrounding tissues. These interactions regulate proinflammatory cytokine-mediated cartilage destruction, contributing to OA progression as well as cartilage repair. This review explores the pathogenesis of OA in the context of the multiple tissue types in the joint and discusses the implications of such complex tissue interaction in the development of anti-inflammatory therapeutics for the treatment of OA. PMID:22745906

  15. Experimental study using optoacoustic spectroscopy (OAS) on spherical gold nanoparticles

    NASA Astrophysics Data System (ADS)

    Lamela, Horacio; Cunningham, Vincent; Gallego, Daniel C.

    2011-02-01

    In this paper a spectroscopic characterisation method based on the optoacoustic technique has been used to investigate the optical properties of two separate spherical gold nanoparticle (SGNP) solutions where an absorption peak located at 520 nm has been observed. This analysis has been carried out over the visible wavelength range from 410 to 650 nm using a Q-switched Nd:YAG pumped optical parametric oscillator (OPO). To verify the reliability of optoacoustic spectroscopy (OAS), the results obtained have been compared to those from more standard and limited spectrophotometer and reference collimated optical transmission schemes, where good agreement is shown. The experimental procedure presented here demonstrates the potential of this technique for integration along with optoacoustic imaging methods to identify physiological information for non-destructive in- vivo applications.

  16. Mx1, OAS1 and OAS2 polymorphisms are associated with the severity of liver disease in HIV/HCV-coinfected patients: A cross-sectional study

    PubMed Central

    García-Álvarez, Mónica; Berenguer, Juan; Jiménez-Sousa, María A.; Pineda-Tenor, Daniel; Aldámiz-Echevarria, Teresa; Tejerina, Francisco; Diez, Cristina; Vázquez-Morón, Sonia; Resino, Salvador

    2017-01-01

    The mechanisms involved in the chronic hepatitis C progression are incompletely understood. The aim was to analyze the association between 2′5′oligoadenylate synthetase 1,2 and 3 (OAS1-3) and myxovirus resistance proteins 1 (Mx1) polymorphisms and severity of liver disease in human immunodeficiency virus (HIV)/hepatitis C virus (HCV) coinfected patients. We performed a cross-sectional study in 219 patients that underwent a liver biopsy. DNA genotyping for Mx1 (rs469390), OAS1 (rs2285934), OAS2 (rs1293762) and OAS3 (rs2010604) was performed by using GoldenGate assay. The outcome variables ion liver biopsy were: (i) significant fibrosis (F ≥ 2); (ii) moderate activity grade (A ≥ 2). Additive model of inheritance for genetic association test was used. The likelihood of having significant fibrosis (F ≥ 2) was lower in patients carrying OAS2 rs1293762 A allele [adjusted odds ratio (aOR) = 0.51; p = 0.040]. Besides, the likelihood of having moderate activity grade (A ≥ 2) was higher in patients carrying Mx1 rs464397 C allele (aOR = 1.63; p = 0.028) and Mx1 rs469390 G allele (aOR = 1.97; p = 0.005), while it was lower in patients carrying OAS1 rs2285934 A allele (aOR = 0.64; p = 0.039) and OAS2 rs1293762 A allele (aOR = 0.41; p = 0.009). In conclusion, Mx1 and OAS1-2 polymorphisms were associated with the severity of liver disease in HIV/HCV-coinfected patients, suggesting a significant role in the progression of hepatic fibrosis. PMID:28139728

  17. X-linked late-onset sensorineural deafness caused by a deletion involving OA1 and a novel gene containing WD-40 repeats.

    PubMed Central

    Bassi, M T; Ramesar, R S; Caciotti, B; Winship, I M; De Grandi, A; Riboni, M; Townes, P L; Beighton, P; Ballabio, A; Borsani, G

    1999-01-01

    We have identified a novel gene, transducin (beta)-like 1 (TBL1), in the Xp22.3 genomic region, that shows high homology with members of the WD-40-repeat protein family. The gene contains 18 exons spanning approximately 150 kb of the genomic region adjacent to the ocular albinism gene (OA1) on the telomeric side. However, unlike OA1, TBL1 is transcribed from telomere to centromere. Northern analysis indicates that TBL1 is ubiquitously expressed, with two transcripts of approximately 2.1 kb and 6.0 kb. The open reading frame encodes a 526-amino acid protein, which shows the presence of six beta-transducin repeats (WD-40 motif) in the C-terminal domain. The homology with known beta-subunits of G proteins and other WD-40-repeat containing proteins is restricted to the WD-40 motif. Genomic analysis revealed that the gene is either partly or entirely deleted in patients carrying Xp22.3 terminal deletions. The complexity of the contiguous gene-syndrome phenotype shared by these patients depends on the number of known disease genes involved in the deletions. Interestingly, one patient carrying a microinterstitial deletion involving the 3' portion of both TBL1 and OA1 shows the OA1 phenotype associated with X-linked late-onset sensorineural deafness. We postulate an involvement of TBL1 in the pathogenesis of the ocular albinism with late-onset sensorineural deafness phenotype. PMID:10330347

  18. Enhancement of Platelet Aggregation by Ursolic Acid and Oleanolic Acid

    PubMed Central

    Kim, Mikyung; Han, Chang-ho; Lee, Moo-Yeol

    2014-01-01

    The pentacyclic triterpenoid ursolic acid (UA) and its isomer oleanolic acid (OA) are ubiquitous in food and plant medicine, and thus are easily exposed to the population through natural contact or intentional use. Although they have diverse health benefits, reported cardiovascular protective activity is contentious. In this study, the effect of UA and OA on platelet aggregation was examined on the basis that alteration of platelet activity is a potential process contributing to cardiovascular events. Treatment of UA enhanced platelet aggregation induced by thrombin or ADP, which was concentration-dependent in a range of 5–50 μM. Quite comparable results were obtained with OA, in which OA-treated platelets also exhibited an exaggerated response to either thrombin or ADP. UA treatment potentiated aggregation of whole blood, while OA failed to increase aggregation by thrombin. UA and OA did not affect plasma coagulation assessed by measuring prothrombin time and activated partial thromboplastin time. These results indicate that both UA and OA are capable of making platelets susceptible to aggregatory stimuli, and platelets rather than clotting factors are the primary target of them in proaggregatory activity. These compounds need to be used with caution, especially in the population with a predisposition to cardiovascular events. PMID:25009707

  19. Omega-9 Oleic Acid Induces Fatty Acid Oxidation and Decreases Organ Dysfunction and Mortality in Experimental Sepsis.

    PubMed

    Gonçalves-de-Albuquerque, Cassiano Felippe; Medeiros-de-Moraes, Isabel Matos; Oliveira, Flora Magno de Jesus; Burth, Patrícia; Bozza, Patrícia Torres; Castro Faria, Mauro Velho; Silva, Adriana Ribeiro; Castro-Faria-Neto, Hugo Caire de

    2016-01-01

    Sepsis is characterized by inflammatory and metabolic alterations, which lead to massive cytokine production, oxidative stress and organ dysfunction. In severe systemic inflammatory response syndrome, plasma non-esterified fatty acids (NEFA) are increased. Several NEFA are deleterious to cells, activate Toll-like receptors and inhibit Na+/K+-ATPase, causing lung injury. A Mediterranean diet rich in olive oil is beneficial. The main component of olive oil is omega-9 oleic acid (OA), a monounsaturated fatty acid (MUFA). We analyzed the effect of OA supplementation on sepsis. OA ameliorated clinical symptoms, increased the survival rate, prevented liver and kidney injury and decreased NEFA plasma levels in mice subjected to cecal ligation and puncture (CLP). OA did not alter food intake and weight gain but diminished reactive oxygen species (ROS) production and NEFA plasma levels. Carnitine palmitoyltransferase IA (CPT1A) mRNA levels were increased, while uncoupling protein 2 (UCP2) liver expression was enhanced in mice treated with OA. OA also inhibited the decrease in 5' AMP-activated protein kinase (AMPK) expression and increased the enzyme expression in the liver of OA-treated mice compared to septic animals. We showed that OA pretreatment decreased NEFA concentration and increased CPT1A and UCP2 and AMPK levels, decreasing ROS production. We suggest that OA has a beneficial role in sepsis by decreasing metabolic dysfunction, supporting the benefits of diets high in monounsaturated fatty acids (MUFA).

  20. Non-covalent complexes of folic acid and oleic acid conjugated polyethylenimine: An efficient vehicle for antisense oligonucleotide delivery

    PubMed Central

    Yang, Shuang; Yang, Xuewei; Liu, Yan; Zheng, Bin; Meng, Lingjun; Lee, Robert J.; Xie, Jing; Teng, Lesheng

    2016-01-01

    Polyethylenimine (PEI) was conjugated to oleic acid (PEI-OA) and evaluated as a delivery agent for LOR-2501, an antisense oligonucleotide against ribonucleotide reductase R1 subunit. PEI-OA/LOR-2501 complexes were further coated with folic acid (FA/PEI-OA/LOR-2501) and evaluated in tumor cells. The level of cellular uptake of FA/PEI-OA/LOR-2501 was more than double that of PEI/LOR-2501 complexes, and was not affected by the expression level of folate receptor (FR) on the cell surface. Efficient delivery was seen in several cell lines. Furthermore, pathway specific cellular internalization inhibitors and markers were used to reveal the principal mechanism of cellular uptake. FA/PEI-OA/LOR-2501 significantly induced the downregulation of R1 mRNA and R1 protein. This novel formulation of FA/PEI-OA provides a reliable and highly efficient method for delivery of oligonucleotide and warrants further investigation. PMID:26263216

  1. A Cross-Cultural Evaluation of the OAS: Measuring Brazilian Occupational Aspirations

    ERIC Educational Resources Information Center

    Hansen, David O.

    1978-01-01

    The study aimed to evaluate empirically the reliability and validity of the Occupational Aspiration Scale (OAS) for southern Brazil. Analyses of mean differences between types of items conformed to expected variations, and the OAS had satisfactory construct validity for the Brazilian sample. However other analyses indicated that it had somewhat…

  2. Sponge OAS has a distinct genomic structure within the 2-5A synthetase family.

    PubMed

    Reintamm, Tõnu; Kuusksalu, Anne; Metsis, Madis; Päri, Mailis; Vallmann, Kerli; Lopp, Annika; Justesen, Just; Kelve, Merike

    2008-11-01

    2',5'-Oligoadenylate synthetases (2-5A synthetases, OAS) are enzymes that play an important role in the interferon-induced antiviral defense mechanisms in mammals. Sponges, the evolutionarily lowest multicellular animals, also possess OAS; however, their function is presently unclear. Low homology between primary structures of 2-5A synthetases from vertebrates and sponges renders their evolutionary relationship obscure. The genomic structure of vertebrate OASs has been thoroughly examined, making it possible to elucidate molecular evolution and expansion of this gene family. Until now, no OAS gene structure was available from sponges to compare it with the corresponding genes from higher organisms. In the present work, we determined the exon/intron structure of the OAS gene from the marine sponge Geodia cydonium and found it to be completely different from the strictly conserved exon/intron pattern of the OAS genes from vertebrates. This finding was corroborated by the analysis of OAS genes from another sponge, Amphimedon queenslandica, whose genome was recently sequenced. Our data suggest that vertebrate and sponge OAS genes have no direct common intron-containing ancestor and two (sub)types of OAS may be discriminated. This study opens new perspectives for understanding the phylogenesis and evolution of 2-5A synthetases as well as functional aspects of this multigene family.

  3. 41 CFR 102-85.20 - What does an Occupancy Agreement (OA) do?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 85-PRICING POLICY FOR OCCUPANCY IN GSA SPACE Pricing Policy-General § 102-85.20 What does an Occupancy Agreement (OA) do? An OA defines GSA's relationship with each customer agency and: (a) Establishes specific financial...

  4. Physical properties of edible emulsified films based on carboxymethyl cellulose and oleic acid.

    PubMed

    Ghanbarzadeh, Babak; Almasi, Hadi

    2011-01-01

    Glycerol and oleic acid (OA) were incorporated into carboxymethyl cellulose (CMC) films by an emulsification method. Films containing different amounts of glycerol and OA were examined for mechanical properties, water vapor permeability (WVP), and moisture uptake, optical and thermal properties. Addition of OA to the CMC films significantly improved the barrier property. However, the effect of OA on the mechanical properties was lower than glycerol. By increasing of OA content, the cloudiness of the CMC films was intensified and Hunter value (b) of the films increased (by ca. 35.8%).

  5. Differential regulation of placental amino acid transport by saturated and unsaturated fatty acids.

    PubMed

    Lager, Susanne; Jansson, Thomas; Powell, Theresa L

    2014-10-15

    Fatty acids are critical for normal fetal development but may also influence placental function. We have previously reported that oleic acid (OA) stimulates amino acid transport in primary human trophoblasts (PHTs). In other tissues, saturated and unsaturated fatty acids have distinct effects on cellular signaling, for instance, palmitic acid (PA) but not OA reduces IκBα expression. We hypothesized that saturated and unsaturated fatty acids differentially affect trophoblast amino acid transport and cellular signaling. To test this hypothesis, PHTs were cultured in docosahexaenoic acid (DHA; 50 μM), OA (100 μM), or PA (100 μM). DHA and OA were also combined to test whether DHA could counteract the OA stimulatory effect on amino acid transport. The effects of fatty acids were compared against a vehicle control. Amino acid transport was measured by isotope-labeled tracers. Activation of inflammatory-related signaling pathways and the mechanistic target of rapamycin (mTOR) pathway were determined by Western blot analysis. Exposure of PHTs to DHA for 24 h reduced amino acid transport and phosphorylation of p38 MAPK, STAT3, mTOR, eukaryotic initiation factor 4E-binding protein 1, and ribosomal protein (rp)S6. In contrast, OA increased amino acid transport and phosphorylation of ERK, mTOR, S6 kinase 1, and rpS6. The combination of DHA with OA increased amino acid transport and rpS6 phosphorylation. PA did not affect amino acid transport but reduced IκBα expression. In conclusion, these fatty acids differentially regulated placental amino acid transport and cellular signaling. Taken together, these findings suggest that dietary fatty acids could alter the intrauterine environment by modifying placental function, thereby having long-lasting effects on the developing fetus.

  6. Anthropometrics provide a better estimate of urinary organic acid anion excretion than a dietary mineral intake-based estimate in children, adolescents, and young adults.

    PubMed

    Berkemeyer, Shoma; Remer, Thomas

    2006-05-01

    The role of elevated net endogenous acid production (NEAP) in the causation of osteoporosis, muscle wasting, and kidney stones is currently under discussion. The aim of this study was to examine whether urinary organic acid anion excretion, a major component of NEAP, is predicted primarily by anthropometric- (OA(anthro)) or diet- (OA(diet)) based estimates. Dietary intakes, anthropometric data, and 24-h urinary excretion rates of organic acids (24h-OA(urine)) were determined cross sectionally in healthy children (6-7 y; n = 217), adolescents (13-14 y; n = 91), and young adults (18-22 y; n = 82). OA(anthro) was computed from body surface area and OA(diet) calculated using a published algorithm based on dietary intakes of mineral anions and cations. There was a significant increase (P < 0.0001) in 24h-OA(urine) across the age groups that was no longer discernible after correction for body surface area. In almost all sex-stratified subsamples, OA(anthro) had a higher correlation with 24h-OA(urine) than OA(diet). Multiple regression analyses, using energy-corrected diet variables, revealed that OA(anthro) was consistently the primary predictor of 24h-OA(urine) (R(2) varying from 0.15 to 0.39) and dietary fat and protein were sporadic predictors. In accordance with the observed age independency of 24h-OA(urine) after body surface area correction, our findings indicate that OA(anthro) is a better estimate of 24h-OA(urine) in healthy children, adolescents, and young adults than OA(diet). This further confirms that the (principally diet-dependent) NEAP comprises a component, i.e., organic acid anions, that is reasonably predictable by anthropometrics. Consequently, the other component, i.e., the potential renal acid load, appears to be the primary parameter that characterizes the diet-induced acid load.

  7. Esterification of DSP toxins by Portuguese bivalves from the Northwest coast determined by LC-MS--a widespread phenomenon.

    PubMed

    Vale, Paulo; Sampayo, Maria Antónia de M

    2002-01-01

    Okadaic acid (OA) and dinophysistoxin-2 (DTX2) were confirmed by liquid chromatography with mass spectrometry detection both in extracts of digestive glands and edible parts of Portuguese shellfish. No dinophysistoxin-1 was found even in highly contaminated samples examined. However, only in blue mussel (Mytilus edulis) were these two parent toxins commonly found in a free form. Usually they were found largely esterified in all remaining shellfish species-common cockle (Cerastoderma edule), peppery furrow shell (Scrobicularia plana), carpet shell (Venerupis pullastra), oyster (Crassostrea japonica), razor clam (Ensisspp.), and clam (Ruditapes decussata). Oysters were the least toxic. In mussels esterified OA did not surpass 50% of the total OA found in edible parts, while DTX2 esterification rates were usually much lower. In remaining shellfish species usually more than 95% of the total OA was found esterified, while free DTX2 was rarely found. Also ratios of total DTX2/total OA were higher in mussels than in the remaining species examined. From all these species commercially exploited at the northern coast, mussels and cockles contained the highest levels of DSP toxins, thus representing the highest theoretical health risk. The previous association of DTX2 with the dinoflagellate Dinophysis acuta was confirmed with selective MS detection; while OA was the only parent diarrhoeic toxin found associated with Dinophysis acuminata.

  8. OAS Gene Family Expression Is Associated with HIV-Related Neurocognitive Disorders.

    PubMed

    Sanfilippo, C; Pinzone, M R; Cambria, D; Longo, A; Palumbo, M; Di Marco, R; Condorelli, F; Nunnari, G; Malaguarnera, L; Di Rosa, M

    2017-02-24

    HIV-associated neurocognitive disorders are common in HIV-infected individuals, even in the combination antiretroviral therapy (c-ART) era. Several mechanisms are involved in neuronal damage, including chronic inflammation immune activation. Mammalian 2'-5'-oligoadenylate synthetase (OAS) genes are produced in response to interferon (IFN), mainly by monocytes, and exert their antiviral functions by activation of RNase L that degrades viral and cellular RNAs. In this study, we aimed at exploring OAS gene family RNA expression in simian immunodeficiency virus encephalitis (SIVE), in HIV-associated neurocognitive disorders (HAND), and in HIV-associate dementia (HAD). We analyzed three microarray datasets obtained from the NCBI in order to assess the expression levels of OAS gene family network in brain biopsies of macaques with SIVE vs uninfected animals, as well as post-mortem brain of individuals with HAND (on or off ART) vs uninfected controls and three brain regions of HIV-infected individuals with both neurocognitive impairment (HAD) and encephalitis (HIVE). All OAS genes were upregulated both in SIVE and in HAND. OAS expression was significantly higher in high-viremic individuals; increased expression levels persisted in cART subjects when compared to healthy controls. OAS gene network analysis showed that several genes belonging to the type I IFN pathway, especially CXCL10 and IFIT3, were similarly upregulated in SIVE/HAND. Furthermore, we identified a significant upregulation of OAS gene family RNA expression in basal ganglia, white matter, and frontal cortex of HIV-1, HAD, and HAD/HIVE patients compared to healthy subjects. OAS gene family expression is increased in brain sections from individuals with HAND, HAD, and HIVE as well as macaques with SIVE. OAS family expression is likely to be induced by IFN as a consequence of viral replication in the CNS. Its long-term upregulation may contribute to the chronic inflammatory status and neurocognitive impairment

  9. The control of Varroa destructor using oxalic acid.

    PubMed

    Gregorc, Ales; Planinc, I

    2002-05-01

    Twenty-four honeybee (Apis mellifera) colonies were used to monitor the efficacy of a solution of 2.9% oxalic acid (OA) and 31.9% sugar against the mite Varroa destructor. Mite mortality was established prior to and after OA treatments, which were conducted in August and September. The treatments resulted in 37% mite mortality as opposed to 1.11% in the controls. OA treatment conducted in September on previously untreated colonies resulted in 25% mite mortality. OA treatments in October and November resulted in approximately 97% mite mortality. These results suggest that OA is effective during the broodless period and less effective when applied to colonies with capped broods. The possible use of OA against the Varroa mite in honeybee colonies as an alternative to routine chemical treatments is discussed.

  10. Oleanolic acid alters bile acid metabolism and produces cholestatic liver injury in mice

    PubMed Central

    Liu, Jie; Lu, Yuan-Fu; Zhang, Youcai; Wu, Kai Connie; Fan, Fang; Klaassen, Curtis D.

    2013-01-01

    Oleanolic acid (OA) is a triterpenoids that exists widely in plants. OA is effective in protecting against hepatotoxicants. Whereas a low dose of OA is hepatoprotective, higher doses and longer-term use of OA produce liver injury. This study characterized OA-induced liver injury in mice. Adult C57BL/6 mice were given OA at doses of 0, 22.5, 45, 90, and 135 mg/kg, s.c., daily for 5 days, and liver injury was observed at doses of 90 mg/kg and above, as evidenced by increases in serum activities of alanine aminotransferase and alkaline phosphatase, increases in serum total bilirubin, as well as by liver histopathology. OA-induced cholestatic liver injury was further evidenced by marked increases of both unconjugated and conjugated bile acids (BAs) in serum. Gene and protein expression analysis suggested that livers of OA-treated mice had adaptive responses to prevent BA accumulation by suppressing BA biosynthetic enzyme genes (Cyp7a1, 8b1, 27a1, and 7b1); lowering BA uptake transporters (Ntcp and Oatp1b2); and increasing a BA efflux transporter (Ostβ). OA increased the expression of Nrf2 and its target gene, Nqo1, but decreased the expression of AhR, CAR and PPARα along with their target genes, Cyp1a2, Cyp2b10 and Cyp4a10. OA had minimal effects on PXR and Cyp3a11. Taken together, the present study characterized OA-induced liver injury, which is associated with altered BA homeostasis, and alerts its toxicity potential. PMID:23948738

  11. CAISI Operational Assessment (OA) data collection results. Final report

    SciTech Connect

    1997-01-31

    One of the lessons learned from Operation Desert Shield/Storm was the inability of deployed Combat Service Support (CSS) computers to exchange data effectively in a battlefield environment. The work-around solution to this previously identified problem has been to physically carry floppy disks between computers. A General Officer Steering Committee, directed by the Vice Chief of Staff of the Army, determined that immediate corrective action was necessary to ensure viability of the CSS Battlefield Mission Area. The study recommended that a three-phased system development plan address short-, mid- and long-term CSS automation communication interface requirements. In response to this study, Program Executive Office (PEO) Standard Army Management Information System (STAMIS) authorized the development of the CSS Automated Information System Interface (CAISI). Phase I (Near-Term) equipped the {open_quotes}first to fight{close_quotes} Contingency Corps units. Phase II (Mid-Term) is being fielded to the remainder of Force Package One units in the active force. Phase III (Long-Term) will equip the remaining units. CAISI is now in the early stages of Phase II fielding. Prior to full Phase II fielding, CAISI must be approved for production by a Milestone III decision authority. Part of the data that will be used in the Milestone III decision is a demonstration of the CAISI`s operational suitability, as assessed by the US Army Operational Test and Evaluation Command (OPTEC). This assessment will be performed through an Operational Assessment (OA) using data provided from previous technical testing, such as the CAISI Customer User Test (CUT), and a field training exercise conducted by units of the XVIII Airborne Corps. The field training exercise data collection took place during two events.

  12. Effect of perfluoroalkyl chain length on monolayer behavior of partially fluorinated oleic acid molecules at the air-water interface.

    PubMed

    Baba, Teruhiko; Takai, Katsuki; Takagi, Toshiyuki; Kanamori, Toshiyuki

    2013-01-01

    A series of oleic acid (OA) analogs containing terminal perfluoroalkyl groups (CF3, C2F5, n-C3F7, n-C4F9 or n-C8F17) was synthesized to clarify how the fluorinated chain length affects the stability and molecular packing of liquid-expanded OA monolayers at the air-water interface. Although the substitution of terminal CF3 group for CH3 in OA had no effect on monolayer stability, further fluorination led to a gradual increase in monolayer stability at 25 °C. Surface pressure-area isotherm revealed that partially fluorinated OA analogs form more expanded monolayers than OA at low surface pressures, and that the monolayer behavior of OA analogs with the even-carbon numbered fluorinated chain is almost the same as that of OA upon monolayer compression, whereas the behavior of OA analogs with the odd-carbon numbered fluorinated chain significantly differs from that of OA. These results indicate: (i) the terminal short part (at least C2 residue) in OA predominantly determines the liquid-expanded monolayer stability; (ii) the molecular packing state of OA may be perturbed by the substitution of a short odd-carbon numbered fluorinated chain; (iii) hence, OA analogs with even-carbon numbered chain are considered to be preferable as hydrophobic building blocks for the synthesis of fluorinated phospholipids.

  13. Differences in metabolism of the marine biotoxin okadaic acid by human and rat cytochrome P450 monooxygenases.

    PubMed

    Kolrep, Franziska; Hessel, Stefanie; These, Anja; Ehlers, Anke; Rein, Kathleen; Lampen, Alfonso

    2016-08-01

    The ingestion of seafood contaminated with the marine biotoxin okadaic acid (OA) can lead to diarrhetic shellfish poisoning with symptoms like nausea, vomiting and abdominal cramps. Both rat and the human hepatic cytochrome P450 monooxygenases (CYP) metabolize OA. However, liver cell toxicity of metabolized OA is mainly unclear. The aim of our study was to detect the cellular effects in HepG2 cells exposed to OA in the presence of recombinant CYP enzymes of both rat and human for the investigation of species differences. The results should be set in correlation with a CYP-specific metabolite pattern. Comparative metabolite profiles of OA after incubation in rat and human recombinant CYP enzymes were established by using LC-MS/MS technique. Results demonstrated that metabolism of OA to oxygenated metabolites correlates with detoxification which was mainly catalyzed by human CYP3A4 and CYP3A5. Detoxification by rat Cyp3a1 was lower compared to human CYP3A enzymes and activation of OA by Cyp3a2 was observed, coincident with minor overall conversion capacity of OA. By contrast human and rat CYP1A2 seem to activate OA into cytotoxic intermediates. In conclusion, different mechanisms of OA metabolism may occur in the liver. At low OA doses, the human liver is likely well protected against cytotoxic OA, but for high shellfish consumers a potential risk cannot be excluded.

  14. Operational results for the experimental DOE/NASA Mod-OA wind turbine project

    NASA Technical Reports Server (NTRS)

    Shaltens, R. K.; Birchenough, A. G.

    1983-01-01

    The Mod-OA wind turbine project which was to gain early experience in the operation of large wind turbines in a utility environment is discussed. The Mod-OA wind turbines were a first generation design, and even though not cost effective, the operating experience and performance characteristics had a significant effect on the design and development of the second and third generation machines. The Mod-OA machines were modified as a result of the operational experience, particularly the blade development and control system strategy. The results of study to investigate the interaction of a Mod-OA wind turbine with an isolated diesel generation system are discussed. The machine configuration, its advantages and disadvantages and the machine performance and availability are discussed.

  15. 15 CFR 742.17 - Exports of firearms to OAS member countries.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... activities as drug trafficking, terrorism, and transnational organized crime. (c) Contract sanctity. Contract..., terrorism, and transnational organized crime. (e) OAS member countries to which firearms controls under this... Salvador, Grenada, Guatemala, Guyana, Haiti, Honduras, Jamaica, Mexico, Nicaragua, Panama, Paraguay,...

  16. 15 CFR 742.17 - Exports of firearms to OAS member countries.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... activities as drug trafficking, terrorism, and transnational organized crime. (c) Contract sanctity. Contract..., terrorism, and transnational organized crime. (e) OAS member countries to which firearms controls under this... Salvador, Grenada, Guatemala, Guyana, Haiti, Honduras, Jamaica, Mexico, Nicaragua, Panama, Paraguay,...

  17. Multiple irradiation sensing of the optical effective attenuation coefficient for spectral correction in handheld OA imaging.

    PubMed

    Held, K Gerrit; Jaeger, Michael; Rička, Jaro; Frenz, Martin; Akarçay, H Günhan

    2016-06-01

    Spectral optoacoustic (OA) imaging enables spatially-resolved measurement of blood oxygenation levels, based on the distinct optical absorption spectra of oxygenated and de-oxygenated blood. Wavelength-dependent optical attenuation in the bulk tissue, however, distorts the acquired OA spectrum and thus makes quantitative oxygenation measurements challenging. We demonstrate a correction for this spectral distortion without requiring a priori knowledge of the tissue optical properties, using the concept of multiple irradiation sensing: recording the OA signal amplitude of an absorbing structure (e.g. blood vessel), which serves as an intrinsic fluence detector, as function of irradiation position. This permits the reconstruction of the bulk effective optical attenuation coefficient μeff,λ . If performed at various irradiation wavelengths, a correction for the wavelength-dependent fluence attenuation is achieved, revealing accurate spectral information on the absorbing structures. Phantom studies were performed to show the potential of this technique for handheld clinical combined OA and ultrasound imaging.

  18. A candidate gene for X-linked Ocular Albinism (OA1)

    SciTech Connect

    Bassi, M.T.; Schiaffino, V.; Rugarli, E.

    1994-09-01

    Ocular Albinism of the Nettleship-Fall type 1 (OA1) is the most common form of ocular albinism. It is transmitted as an X-linked recessive trait with affected males showing severe reduction of visual acuity, nystagmus, strabismus, photophobia. Ophthalmologic examination reveals foveal hypoplasia, hypopigmentation of the retina and iris translucency. Microscopic examination of melanocytes suggests that the underlying defect in OA1 is an abnormality in melanosome formation. Recently we assembled a 350 kb cosmid contig spanning the entire critical region on Xp22.3, which measures approximately 110 kb. A minimum set of cosmids was used to identify transcribed sequences using both cDNA selection and exon amplification. Two putative exons recovered by exon amplification strategy were found to be highly conserved throughout evolution and, therefore, they were used as probes for the screening of fetal and adult retina cDNA libraries. This led to the isolation of clones spanning a full-length cDNA which measures 7.6 kb. Sequence analysis revealed that the predicted protein product shows homology with syntrophines and a Xenopus laevis apical protein. The gene covers approximately 170 kb of DNA and spans the entire critical region for OA1, being deleted in two patients with contiguous gene deletion including OA1 and in one patient with isolated OA1. Therefore, this new gene represents a very strong candidate for involvement in OA1 (an alternative, but unlikely possibility to be considered is that the true OA1 gene lies within an intron of the former). Northern analysis revealed very high level of expression in retina and melanoma. Unlike most Xp22.3 genes, this gene is conserved in the mouse. We are currently performing SSCP analysis and direct sequencing of exons on DNAs from approximately 60 unrelated patients with OA1 for mutation detection.

  19. BOREAS TF-1 SSA-OA Weekly Tower CH4 and N2O Flux

    NASA Technical Reports Server (NTRS)

    Thurtell, George; Edwards, Grant; Simpson, George; Hall, Forrest G. (Editor); Huemmrich, Karl (Editor)

    2000-01-01

    The BOREAS TF-1 team collected various trace gas and energy flux data in its efforts to characterize the temporal energy and gas exchanges that occurred over the SSA-OA site. This data set contains methane (CH4) and nitrous oxide (N2O) fluxes that were measured at the BOREAS SSA-OA site. These fluxes were measured from 16-Apr to 16-Sep-1994. The data were averaged to weekly values and are available in tabular ASCII files.

  20. Molecular mechanism of flip-flop in triple-layer oleic-acid membrane: correlation between oleic acid and water.

    PubMed

    Ngo, Van A; Kalia, Rajiv K; Nakano, Aiichiro; Vashishta, Priya

    2012-11-15

    We perform all-atom molecular dynamics simulations to study a pure oleic acid (OA) membrane in water that results in a triple-layer structure. We compute the pressure profiles to examine the hydrophobic and hydrophilic regions, and to estimate the surface tension (≈34.5 mN/m), which is similar to those of lipid membranes. We observe that the membrane of OAs having a large diffusion coefficient (0.4 × 10(-7) cm(2)/s) along the normal to the membrane is an ideal model to study oleic acid flip-flop. In the model, the membrane contains a middle layer serving as an intermediate for water and OAs to easily migrate (flip-flop) from one to other leaflets. Water molecules surrounding OA head-groups help to reduce the barriers at the hydrophobic interface to trigger flip-flop events. Within 500 ns, we observe 175 flip-flop events of OAs and 305 events of water traversing the membrane. The ratio of water passing rate (k(H(2)O) = 0.673 ns(-1)) to OA flip-flop rate (k(OA) = 0.446 ns(-1)) is 3/2. The ratio of the totally correlated water-OA events to the totally uncorrelated water-OA events, n(cor)/n(uncor), is also 3/2. The probability of the totally and partially correlated events is 69%. The results indicate that the trans-membrane movement of water and OAs is cooperative and correlated, and agrees with experimentally measured absorption rates. They support the idea that OA flip-flop is more favorable than transport by means of functional proteins. This study might provide further insight into how primitive cell membranes work, and how the interplay and correlation between water and fatty acids may occur.

  1. Oleanolic acid ameliorates high glucose-induced endothelial dysfunction via PPARδ activation

    PubMed Central

    Zhang, Zihui; Jiang, Manli; Xie, Xinya; Yang, Haixia; Wang, Xinfeng; Xiao, Lei; Wang, Nanping

    2017-01-01

    Oleanolic acid (3β-hydroxyolean-12-en-28-oic acid, OA) is a pentacyclic triterpenes widely distributed in food, medicinal plants and nutritional supplements. OA exhibits various pharmacological properties, such as hepatoprotective and anti-tumor effects. In this study, we analyzed the effect of OA on endothelial dysfunction induced by high glucose in human vascular endothelial cells (ECs). Western blotting showed that OA attenuated high glucose-reduced nitric production oxide (NO) as well as Akt-Ser473 and eNOS-Ser1177 phosphorylation in cultured human umbilical vein ECs (HUVECs). Next, luciferase reporter assay showed that OA activated peroxisome proliferators-activated receptor δ (PPARδ) activity. Quantitative reverse transcriptase PCR (qRT-PCR) demonstrated that OA increased the expressions of PPARδ target genes (PDK4, ADRP and ANGPTL4) in ECs. Meanwhile, the induced expressions of PDK4, ADRP and ANGPTL4 by OA were inhibited by GSK0660, a specific antagonist of PPARδ. In addition, inhibition of PPARδ abolished OA-induced the Akt-Ser473 and eNOS-Ser1177 phosphorylation, and NO production. Finally, by using Multi Myograph System, we showed that OA prevented high glucose-impaired vasodilation. This protective effect on vasodilation was inhibited in aortic rings pretreated with GSK0660. Collectively, we demonstrated that OA improved high glucose-impaired endothelial function via a PPARδ-mediated mechanism and through eNOS/Akt/NO pathway. PMID:28067284

  2. Synthesis of novel oleanolic acid and ursolic acid in C-28 position derivatives as potential anticancer agents.

    PubMed

    Tian, Tian; Liu, Xinyu; Lee, Eung-Seok; Sun, Jingyang; Feng, Zhonghua; Zhao, Longxuan; Zhao, Chunhui

    2017-04-01

    A series of nitrogen-containing derivatives of oleanolic acid and ursolic acid were prepared by a modification at C-28 position via esterification with 2-hydroxyacetic acid followed by amidation with amines, such as piperazine, N-methylpiperazine, and alkane-1, 2-diamines, alkane-1, 4-diamines, alkane-1, 6-diamines. In vitro antiproliferative activities of the compounds prepared towards MCF-7, Hela and A549 cell lines were evaluated by a MTT method to show that OA-5a, OA-5b, OA-5c and UA-5a showed somewhat improved antiproliferative activities against MCF-7, Hela and A549 cells comparing to that of the positive control, gefitinib.

  3. “Let’s Talk about OA Pain”: A Qualitative Analysis of the Perceptions of People Suffering from OA. Towards the Development of a Specific Pain OA-Related Questionnaire, the Osteoarthritis Symptom Inventory Scale (OASIS)

    PubMed Central

    Cedraschi, Christine; Delézay, Sylvie; Marty, Marc; Berenbaum, Francis; Bouhassira, Didier; Henrotin, Yves; Laroche, Françoise; Perrot, Serge

    2013-01-01

    Introduction Pain is the primary outcome measurement in osteoarthritis, and its assessment is mostly based on its intensity. The management of this difficult chronic condition could be improved by using pain descriptors to improve analyses of painful sensations. This should help to define subgroups of patients based on pain phenotype, for more adapted treatment. This study draws upon patients’ descriptions of their pain, to identify and understand their perception of osteoarthritis pain and to categorize pain dimensions. Methods This qualitative study was conducted with representative types of patients suffering from osteoarthritis. Two focus groups were conducted with a sample of 14 participants, with either recent or chronic OA, at one or multiple sites. Focus groups were semi-structured and used open-ended questions addressing personal experiences to explore the experiences of patients with OA pain and the meanings they attributed to these pains. Results Two main points emerged from content analyses: -A major difficulty in getting patients to describe their osteoarthritis pain: perception that nobody wants to hear about it; necessity to preserve one’s self and social image; notion of self-imposed stoicism; and perception of osteoarthritis as a complex, changing, illogical disease associated with aging. -Osteoarthritis pains were numerous and differed in intensity, duration, depth, type of occurrence, impact and rhythm, but also in painful sensations and associated symptoms. Based on analyses of the verbatim interviews, seven dimensions of OA pain emerged: pain sensory description, OA-related symptoms, pain variability profile, pain-triggering factors, pain and physical activity, mood and image, general physical symptoms. Summary In osteoarthritis, pain analysis should not be restricted to intensity. Our qualitative study identified pain descriptors and defined seven dimensions of osteoarthritis pain. Based on these dimensions, we aim to develop a specific

  4. The Effects of Transdermally Delivered Oleanolic Acid on Malaria Parasites and Blood Glucose Homeostasis in P. berghei-Infected Male Sprague-Dawley Rats

    PubMed Central

    Mabandla, Musa V.

    2016-01-01

    The present study investigated the effects of transdermally delivered oleanolic acid (OA) monotherapy and in combination with chloroquine (CHQ) on malaria parasites and glucose homeostasis of P. berghei-infected male Sprague-Dawley rats. Oral glucose test (OGT) responses to OA-pectin patch and CHQ-OA combination matrix patch were monitored in non-infected and infected rats. To evaluate the short-term effects of treatment, percentage parasitaemia, blood glucose, glycogen and plasma insulin were monitored in separate groups of animals treated with either OA-patch monotherapy or CHQ-OA combination pectin patch over a 21-days period. Animals treated with drug-free pectin and CHQ acted as untreated and treated positive controls, respectively. Infected control rats exhibited significantly increased parasitaemia which was accompanied by hypoglycaemia. Both OA monotherapy and CHQ-OA combination therapy reduced and cleared the malaria parasites within a period of 4 and 3 days, respectively. Compared to respective controls groups, OGT responses of animals treated with OA monotherapy or CHQ-OA combination therapy exhibited lower blood glucose levels at all time points. A once-off transdermal application of OA-patch or CHQ-OA combination patch significantly improved blood glucose concentrations inducing any changes in insulin concentration. Transdermal OA used as a monotherapy or in combination with CHQ is able to clear and reduce the malaria parasites within a shorter period of time without eliciting any adverse effects on glucose homeostasis of P. berghei-infected rats. PMID:27907019

  5. Identification of 19-epi-okadaic Acid, a New Diarrhetic Shellfish Poisoning Toxin, by Liquid Chromatography with Mass Spectrometry Detection

    PubMed Central

    Paz, Beatriz; Daranas, Antonio H.; Cruz, Patricia G.; Franco, José M.; Norte, Manuel; Fernández, José J.

    2008-01-01

    Okadaic acid (1) (OA) and its congeners are mainly responsible for diarrhetic shellfish poisoning (DSP) syndrome. The presence of several OA derivatives have already been confirmed in Prorocentrum and Dinophysis spp. In this paper, we report on the detection and identification of a new DSP toxin, the OA isomer 19-epi-okadaic acid (2) (19-epi-OA), isolated from cultures of Prorocentrum belizeanum, by determining its retention time (RT) and fragmentation pattern using liquid chromatography coupled with mass spectrometry (LC–MS/MS). PMID:19005581

  6. Anti-glycative effects of oleanolic acid and ursolic acid in kidney of diabetic mice.

    PubMed

    Wang, Zhi-hong; Hsu, Cheng-chin; Huang, Chien-ning; Yin, Mei-chin

    2010-02-25

    Inhibitory effects of oleanolic acid (OA) and ursolic acid (UA) on aldose reductase (AR) and glycative products in kidney of diabetic mice were examined. OA or UA at 0.05, 0.1 or 0.2% was supplied for 10 weeks. Diabetic mice with 0.1 or 0.2% OA or UA treatments had significantly higher body weight and lower kidney weight at weeks 5 and 10 (P<0.05). OA or UA intake at 0.1 or 0.2% increased their content in the kidney, dose-dependently decreased plasma glucose, HbA1c, renal N(epsilon)-(carboxymethyl)lysine, urinary glycated albumin and urinary albumin levels; elevated plasma insulin and renal creatinine clearance levels; as well as decreased renal sorbitol and fructose concentrations (P<0.05). OA or UA treatments at 0.1 and 0.2% also significantly diminished renal AR activity and dose-dependently down-regulated renal AR mRNA expression (P<0.05). These two compounds at 0.2% significantly reduced renal sorbitol dehydrogenase activity (P<0.05). OA, not UA, treatments at 0.1 or 0.2% dose-dependently enhanced renal glyoxalase I (GLI) activity, up-regulated renal GLI mRNA expression and lowered renal methylglyoxal level (P<0.05). Based on these marked anti-glycative effects, the supplement of OA or UA might be helpful for the prevention or alleviation of glycation associated renal diseases.

  7. Anti-anaphylactic action of nordihydroguaiaretic acid in antigen sensitized guinea pigs.

    PubMed

    Bergren, Dale R; Valentine, Jimmie L

    2016-12-01

    Therapeutic natural products and medicinal herbs has gained popularity. The anti-antigenic action of the plant alkaloid nordihydroguaiaretic acid (NDGA) was studied in ovalbumin (OA)-sensitized guinea pigs. In one series of experiments conscious, non-sedated guinea pigs were challenged with OA aerosol. Specific airway resistance (SRAW) was monitored using a two-chambered whole-body plethysmograph. OA aerosol increased SRAW above that produced by vehicle administration. Prior NDGA administration by a 1min 0.9% aerosol (w/vol) attenuated the increase in SRAW resulting from OA challenge. In the anesthetized guinea pig pretreated with indomethacin, pyrilamine and propranolol, intravenous OA injection increased intra-tracheal pressure above vehicle injection. Intravenous NDGA administration (5mg/kg) reduced the intra-tracheal pressure increases. In a third series of experiments plasma leukotriene C4 was measured by radio-immunoassay in 3 groups challenged with OA aerosol: vehicle-treated OA-sensitized, OA-sensitized receiving NDGA and vehicle treated guinea pigs. NDGA pretreatment reduced plasma LTC4 in response to OA challenge in OA sensitized guinea pigs. This study demonstrates that NDGA is an effective antigenic agent when given by aerosol or intravenous injection in either conscious or anesthetized guinea pigs, respectively. The mechanism of action of NDGA is presumed primarily be due to the blockage of 5-lipoxygenase and therefore the synthesis of leukotrienes.

  8. Genomic and functional characterization of the oas gene family encoding O-acetylserine (thiol) lyases, enzymes catalyzing the final step in cysteine biosynthesis in Arabidopsis thaliana.

    PubMed

    Jost, R; Berkowitz, O; Wirtz, M; Hopkins, L; Hawkesford, M J; Hell, R

    2000-08-08

    The final step of cysteine biosynthesis in plants is catalyzed by O-acetylserine (thiol) lyase (OAS-TL), which occurs as several isoforms found in the cytosol, the plastids and the mitochondria. Genomic DNA blot hybridization and isolation of genomic clones indicate single copy genes (oasA1, oasA2, oasB and oasC) that encode the activities of OAS-TL A, B and C found in separate subcellular compartments in the model plant Arabidopsis thaliana. Sequence analysis reveals that the newly discovered oasA2 gene represents a pseudogene that is still transcribed, but is not functionally translated. The comparison of gene structures suggests that oasA1/oasA2 and oasB/oasC are closely related and may be derived from a common ancestor by subsequent duplications. OAS-TL A, B and C were overexpressed in an Escherichia coli mutant lacking cysteine synthesis and exhibited bifunctional OAS-TL and beta-cyanoalanine synthase (CAS) activities. However, all three proteins represent true OAS-TLs according to kinetic analysis and are unlikely to function in cyanide detoxification or secondary metabolism. In addition, it was demonstrated that the mitochondrial OAS-TL C exhibits in vivo protein-protein interaction capabilities with respect to cysteine synthase complex formation similar to cytosolic OAS-TL A and plastid OAS-TL B. Multiple database accessions for each of the A. thaliana OAS-TL isoforms can thus be attributed to a specified number of oas genes to which functionally defined gene products are assigned, and which are responsible for compartment-specific cysteine synthesis.

  9. Degradation of oxalic acid by the mycoparasite Coniothyrium minitans plays an important role in interacting with Sclerotinia sclerotiorum.

    PubMed

    Zeng, Li-Mei; Zhang, Jing; Han, Yong-Chao; Yang, Long; Wu, Ming-de; Jiang, Dao-Hong; Chen, Weidong; Li, Guo-Qing

    2014-08-01

    Coniothyrium minitans (Cm) is a mycoparasite of the phytopathogenic fungus Sclerotinia sclerotiorum (Ss). Ss produces a virulence factor oxalic acid (OA) which is toxic to plants and also to Cm, and Cm detoxifies OA by degradation. In this study, two oxalate decarboxylase genes, Cmoxdc1 and Cmoxdc2, were cloned from Cm strain Chy-1. OA and low pH induced expression of Cmoxdc1, but not Cmoxdc2. Cmoxdc1 was partially responsible for OA degradation, whereas Cmoxdc2 had no effect on OA degradation. Disruption of Cmoxdc1 in Cm reduced its ability to infect Ss in dual cultures where OA accumulated. Compared with Chy-1, the Cmoxdc1-disrupted mutants had reduced expression levels of two mycoparasitism-related genes chitinase (Cmch1) and β-1,3-glucanase (Cmg1), and had no detectable activity of extracellular proteases in the presence of OA. On the other hand, the cultural filtrates of the Cmoxdc1-disrupted mutants in OA-amended media showed enhanced antifungal activity, possibly because of increased production of antifungal substances under acidic pH condition resulted from reduced Cmoxdc1-mediated OA degradation. This study provides direct genetic evidence of OA degradation regulating mycoparasitism and antibiosis of Cm against Ss, and sheds light on the sophisticated strategies of Cm in interacting with metabolically active mycelia and dormant sclerotia of Ss.

  10. Comparison of model and observations of the wake of a MOD-OA wind turbine

    SciTech Connect

    Doran, J.C.; Packard, K.R.

    1982-10-01

    A series of wind velocity measurements upwind and downwind of the MOD-OA wind turbine at Clayton, New Mexico, was used to determine some of the characteristics of wakes within approximately two blade diameters of the machine. The magnitudes and shapes of the velocity profiles downwind of the turbine were compared with results obtained from a model. Generally good agreement was obtained at speeds well below the rated speed of the MOD-OA, but the results were not as satisfactory for higher values.

  11. An oleic acid-capped CdSe quantum-dot sensitized solar cell

    SciTech Connect

    Chen Jing; Song, J. L.; Deng, W. Q.; Sun, X. W.; Jiang, C. Y.; Lei, W.; Huang, J. H.; Liu, R. S.

    2009-04-13

    In this letter, we report an oleic acid (OA)-capped CdSe quantum-dot sensitized solar cell (QDSSC) with an improved performance. The TiO{sub 2}/OA-CdSe photoanode in a two-electrode device exhibited a photon-to-current conversion efficiency of 17.5% at 400 nm. At AM1.5G irradiation with 100 mW/cm{sup 2} light intensity, the QDSSCs based on OA-capped CdSe showed a power conversion efficiency of about 1%. The function of OA was to increase QD loading, extend the absorption range and possibly suppress the surface recombination.

  12. Veratrole Biosynthesis in White Campion1[W][OA

    PubMed Central

    Akhtar, Tariq A.; Pichersky, Eran

    2013-01-01

    White campion (Silene latifolia) is a dioecious plant that emits 1,2-dimethoxybenzene (veratrole), a potent pollinator attractant to the nocturnal moth Hadena bicruris. Little is known about veratrole biosynthesis, although methylation of 2-methoxyphenol (guaiacol), another volatile emitted from white campion flowers, has been proposed. Here, we explore the biosynthetic route to veratrole. Feeding white campion flowers with [13C9]l-phenylalanine increased guaiacol and veratrole emission, and a significant portion of these volatile molecules contained the stable isotope. When white campion flowers were treated with the phenylalanine ammonia lyase inhibitor 2-aminoindan-2-phosphonic acid, guaiacol and veratrole levels were reduced by 50% and 63%, respectively. Feeding with benzoic acid (BA) or salicylic acid (SA) increased veratrole emission 2-fold, while [2H5]BA and [2H6]SA feeding indicated that the benzene ring of both guaiacol and veratrole is derived from BA via SA. We further report guaiacol O-methyltransferase (GOMT) activity in the flowers of white campion. The enzyme was purified to apparent homogeneity, and the peptide sequence matched that encoded by a recently identified complementary DNA (SlGOMT1) from a white campion flower expressed sequence tag database. Screening of a small population of North American white campion plants for floral volatile emission revealed that not all plants emitted veratrole or possessed GOMT activity, and SlGOMT1 expression was only observed in veratrole emitters. Collectively these data suggest that veratrole is derived by the methylation of guaiacol, which itself originates from phenylalanine via BA and SA, and therefore implies a novel branch point of the general phenylpropanoid pathway. PMID:23547102

  13. Bovine lactoferrin binds oleic acid to form an anti-tumor complex similar to HAMLET.

    PubMed

    Fang, Bing; Zhang, Ming; Tian, Mai; Jiang, Lu; Guo, Hui Yuan; Ren, Fa Zheng

    2014-04-04

    α-Lactalbumin (α-LA) can bind oleic acid (OA) to form HAMLET-like complexes, which exhibited highly selective anti-tumor activity in vitro and in vivo. Considering the structural similarity to α-LA, we conjectured that lactoferrin (LF) could also bind OA to obtain a complex with anti-tumor activity. In this study, LF-OA was prepared and its activity and structural changes were compared with α-LA-OA. The anti-tumor activity was evaluated by methylene blue assay, while the apoptosis mechanism was analyzed using flow cytometry and Western blot. Structural changes of LF-OA were measured by fluorescence spectroscopy and circular dichroism. The interactions of OA with LF and α-LA were evaluated by isothermal titration calorimetry (ITC). LF-OA was obtained by heat-treatment at pH8.0 with LD50 of 4.88, 4.95 and 4.62μM for HepG2, HT29, and MCF-7 cells, respectively, all of which were 10 times higher than those of α-LA-OA. Similar to HAMLET, LF-OA induced apoptosis in tumor cells through both death receptor- and mitochondrial-mediated pathways. Exposure of tryptophan residues and the hydrophobic regions as well as the loss of tertiary structure were observed in LF-OA. Besides these similarities, LF showed different secondary structure changes when compared with α-LA, with a decrease of α-helix and β-turn and an increase of β-sheet and random coil. ITC results showed that there was a higher binding number of OA to LF than to α-LA, while both of the proteins interacted with OA through van der Waals forces and hydrogen bonds. This study provides a theoretical basis for further exploration of protein-OA complexes.

  14. Octanoic acid in alcohol-responsive essential tremor

    PubMed Central

    McCrossin, Gayle; Lungu, Codrin; Considine, Elaine; Toro, Camilo; Nahab, Fatta B.; Auh, Sungyoung; Buchwald, Peter; Grimes, George J.; Starling, Judith; Potti, Gopal; Scheider, Linda; Kalowitz, Daniel; Bowen, Daniel; Carnie, Andrea; Hallett, Mark

    2013-01-01

    Objective: To assess safety and efficacy of an oral, single, low dose of octanoic acid (OA) in subjects with alcohol-responsive essential tremor (ET). Methods: We conducted a double-blind, placebo-controlled, crossover, phase I/II clinical trial evaluating the effect of 4 mg/kg OA in 19 subjects with ET. The primary outcome was accelerometric postural tremor power of the dominant hand 80 minutes after administration. Secondary outcomes included digital spiral analysis, pharmacokinetic sampling, as well as safety measures. Results: OA was safe and well tolerated. Nonserious adverse events were mild (Common Terminology Criteria for Adverse Events grade 1) and equally present after OA and placebo. At the primary outcome, OA effects were not different from placebo. Secondary outcome analyses of digital spiral analysis, comparison across the entire time course in weighted and nonweighted accelerometry, as well as nondominant hand tremor power did not show a benefit of OA over placebo. The analysis of individual time points showed that OA improved tremor at 300 minutes (dominant hand, F1,16 = 5.49, p = 0.032 vs placebo), with a maximum benefit at 180 minutes after OA (both hands, F1,16 = 6.1, p = 0.025). Conclusions: Although the effects of OA and placebo at the primary outcome were not different, secondary outcome measures suggest superiority of OA in reducing tremor at later time points, warranting further trials at higher dose levels. Classification of evidence: This study provides Class I evidence that a single 4-mg/kg dose of OA is not effective in reducing postural tremor in patients with ET at a primary outcome of 80 minutes, but is effective for a secondary outcome after 180 minutes. PMID:23408867

  15. A New Green Ionic Liquid-Based Corrosion Inhibitor for Steel in Acidic Environments.

    PubMed

    Atta, Ayman M; El-Mahdy, Gamal A; Al-Lohedan, Hamad A; Ezzat, Abdel Rahman O

    2015-06-17

    This work examines the use of new hydrophobic ionic liquid derivatives, namely octadecylammonium tosylate (ODA-TS) and oleylammonium tosylate (OA-TS) for corrosion protection of steel in 1 M hydrochloric acid solution. Their chemical structures were determined from NMR analyses. The surface activity characteristics of the prepared ODA-TS and OA-TS were evaluated from conductance, surface tension and contact angle measurements. The data indicate the presence of a double bond in the chemical structure of OA-TS modified its surface activity parameters. Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) measurements, scanning electron microscope (SEM), Energy dispersive X-rays (EDX) analysis and contact angle measurements were utilized to investigate the corrosion protection performance of ODA-TS and OA-TS on steel in acidic solution. The OA-TS and ODA-TS compounds showed good protection performance in acidic chloride solution due to formation of an inhibitive film on the steel surface.

  16. Effect of a controlled-release drug delivery system made of oleanolic acid formulated into multivesicular liposomes on hepatocellular carcinoma in vitro and in vivo.

    PubMed

    Luo, Yuling; Liu, Zhongbing; Zhang, Xiaoqin; Huang, Juan; Yu, Xin; Li, Jinwei; Xiong, Dan; Sun, Xiaoduan; Zhong, Zhirong

    2016-01-01

    The aim of the present study was to develop a novel dosage form of multivesicular liposomes for oleanolic acid (OA) to overcome its poor solubility, prolong therapeutic drug levels in the blood, and enhance the antitumor effect on hepatocellular carcinoma. OA-encapsulated multivesicular liposomes (OA-MVLs) were prepared by a double-emulsion method, and the formulation was optimized by the central composite design. The morphology, particle size, and drug-loading efficiency of OA-MVLs were investigated. Furthermore, OA-MVLs were also characterized both in vitro and in vivo. The results showed that OA-MVLs were spherical particles with an average particle size of 11.57 μm and an encapsulation efficiency of 82.3%±0.61%. OA-MVLs exhibited a sustained-release pattern in vitro, which was fitted to Ritger-Peppas equation. OA-MVLs inhibited the growth of human HepG2 cells which was confirmed by the MTT assay and fluorescence microscopy detection. The in vivo release of OA from OA-MVLs exhibited a sustained manner, indicating a longer circulation time compared to OA solution. The in vivo toxicity study indicated that medium-dose OA-MVLs exerted no toxic effect on the hosts. Importantly, OA-MVLs suppressed the growth of murine H22 hepatoma and prolonged the survival of tumor-bearing mice. In conclusion, the poorly soluble OA could be encapsulated into MVLs to form a novel controlled-release drug delivery system. The present study may hold promise for OA-MVLs as a new dosage form for sustained-release drug delivery in cancer therapy.

  17. Sources, properties, aging, and anthropogenic influences on OA and SOA over the Southeast US and the Amazon during SOAS, DC3, SEAC4RS, and GoAmazon

    NASA Astrophysics Data System (ADS)

    Jimenez, J. L.; Campuzano Jost, P.; Hu, W.; Palm, B. B.; Thompson, S.; Krechmer, J.; Day, D. A.; Stark, H.; Peng, Z.; Ortega, A. M.; Isaacman, G. A.; Goldstein, A. H.; Holzinger, R.; de Sá, S. S.; Martin, S. T.; Alexander, M. L.; Guenther, A. B.; Canagaratna, M. R.; Massoli, P.; Kimmel, J.; Jayne, J. T.; Worsnop, D. R.; Brune, W. H.; Lee-Taylor, J. M.; Hodzic, A.; Madronich, S.; Offenberg, J. H.; Ferreira De Brito, J.; Artaxo, P.; Manzi, A. O.

    2014-12-01

    The SE US and the Amazon have large sources of biogenic VOCs and varying anthropogenic pollution impact, and often poor aerosol model performance. Recent results on the sources, properties, aging, and impact of anthropogenic pollution on OA and secondary OA (SOA) over these regions will be presented. SOA from IEPOX accounts for 14-17% of the OA on average over the SE US and extending up to 6 km. Higher IEPOX-SOA correlates with airmasses of high isoprene, IEPOX, sulfate, acidity, and lower NO. The IEPOX organosulfate accounts for ~10% of IEPOX-SOA over the SE US. The AMS ion C5H6O+ is shown to be a good marker of IEPOX-SOA, while total m/z 82 (as in ACSM) suffers larger interferences. The sinks of IEPOX-SOA via both OH oxidation and evaporation are slow. The low-volatility of IEPOX-SOA contrasts with the small semivolatile molecules that have so far been identified as its components, suggesting the importance of oligomerization. Urban SOA is estimated to account for 25% of the OA in the SE US using either the GEOS-Chem model or the measured 14C (using recent results that urban SOA (POA) is 30% (50%) non-fossil, mainly due to cooking emissions). An oxidation flow reactor (OFR) is used to investigate SOA formation by OH, O3, and NO3 in-situ. Largest SOA formation is always observed at night when monoterpenes (MT) are largest, and is underpredicted by SOA models that use MT as precursors but ignore partially-oxidized products. Closure results from models (VBS and GECKO-A) that account for the whole oxidation chain will be presented. The partitioning of organic acids is found to proceed rapidly in response to temperature changes, in contrast with recent reports of very slow equilibration. The agreement with absorptive partitioning theory is reasonable for most species, except small acids that may be formed by thermal decomposition during analysis. Partitioning data from four instruments is compared, with reasonable agreement in many cases including the rapid response

  18. Treatment with oleic acid reduces IgE binding to peanut and cashew allergens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oleic acid (OA) is known to bind and change the bioactivities of proteins, such as a-lactalbumin and ß-lactoglobulin in vitro. The objective of this study was to determine if OA binds to allergens from a peanut extract or cashew allergen and changes their allergenic properties. Peanut extract or c...

  19. Structure of equine 2'-5'oligoadenylate synthetase (OAS) gene family and FISH mapping of OAS genes to ECA8p15-->p14 and BTA17q24-->q25.

    PubMed

    Perelygin, A A; Lear, T L; Zharkikh, A A; Brinton, M A

    2005-01-01

    Mammalian 2'-5' oligoadenylate (2-5A) synthetases are important mediators of the antiviral activity of interferons. Both human and mouse 2-5A synthetase gene families encode four forms of enzymes: small, medium, large and ubiquitin-like. In this study, the structures of four equine OAS genes were determined using DNA sequences derived from fifteen cDNA and four BAC clones. Composition of the equine OAS gene family is more similar to that of the human OAS family than the mouse Oas family. Two OAS-containing bovine BAC clones were identified in GenBank. Both equine and bovine BAC clones were physically assigned by FISH to horse and cattle chromosomes, ECA8p15-->p14 and BTA17q24--> q25, respectively. The comparative mapping data confirm conservation of synteny between ungulates, humans and rodents.

  20. Functional Imaging in OA: Role of Imaging in the Evaluation of Tissue Biomechanics

    PubMed Central

    Neu, Corey P.

    2014-01-01

    Functional imaging refers broadly to the visualization of organ or tissue physiology using medical image modalities. In load-bearing tissues of the body, including articular cartilage lining the bony ends of joints, changes in strain, stress, and material properties occur in osteoarthritis (OA), providing an opportunity to probe tissue function through the progression of the disease. Here, biomechanical measures in cartilage and related joint tissues are discussed as key imaging biomarkers in the evaluation of OA. Emphasis will be placed on the a) potential of radiography, ultrasound, and magnetic resonance imaging to assess early tissue pathomechanics in OA, b) relative utility of kinematic, structural, morphological, and biomechanical measures as functional imaging biomarkers, and c) improved diagnostic specificity through the combination of multiple imaging biomarkers with unique contrasts, including elastography and quantitative assessments of tissue biochemistry. In comparison to other modalities, magnetic resonance imaging provides an extensive range of functional measures at the tissue level, with conventional and emerging techniques available to potentially to assess the spectrum of preclinical to advance OA. PMID:25278049

  1. 41 CFR 102-85.20 - What does an Occupancy Agreement (OA) do?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... defines GSA's relationship with each customer agency and: (a) Establishes specific financial terms... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What does an Occupancy Agreement (OA) do? 102-85.20 Section 102-85.20 Public Contracts and Property Management Federal...

  2. 41 CFR 102-85.140 - How are changes in Rent reflected in OAs?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false How are changes in Rent reflected in OAs? 102-85.140 Section 102-85.140 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 85-PRICING POLICY...

  3. BOREAS TF-1 SSA-OA Tower Flux, Meteorological, and Soil Temperature Data

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Huemmrich, Karl (Editor); Black, T. Andrew; Chen, Z.; Nesic, Zoran

    2000-01-01

    The BOREAS TF-1 team collected energy, carbon dioxide, and momentum flux data above the canopy along with meteorological and soils data at the BOREAS SSA-OA site from mid-April to the end of the year for 1996. The data are available in tabular ASCII files.

  4. BOREAS TF-1 SSA-OA Understory Flux, Meteorological, and Soil Temperature Data

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Huemmrich, Karl (Editor); Black, T. Andrew; Chen, Z.; Nesic, Zoran

    2000-01-01

    The BOREAS TF-1 team collected energy, carbon dioxide, and momentum flux data under the canopy along with meteorological and soils data at the BOREAS SSA-OA site from mid-October to mid-November of 1993 and throughout all of 1994. The data are available in tabular ASCII files.

  5. 41 CFR 102-85.205 - What happens if a customer agency continues occupancy after the expiration of an OA?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... assignments. However, provisions are necessary to cover the GSA and customer relationship if an OA expires... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What happens if a customer agency continues occupancy after the expiration of an OA? 102-85.205 Section 102-85.205...

  6. Polymorphisms of interferon-inducible genes OAS associated with interferon-α treatment response in chronic HBV infection.

    PubMed

    Ren, Shan; Yu, Haibin; Zhang, Hongwei; Liu, Ying; Huang, Yanxiang; Ma, Lina; Wei, Lai; Wu, Hao; Chen, Xinyue

    2011-03-01

    To evaluate the role of host single nucleotide polymorphisms (SNPs) of 2',5'-oligoadenylate synthetase (OAS) in predicting IFN response in patients with HBV infection, OAS gene and four SNPs were examined in 363 patients with chronic HBV infection (including 41 patients with HBsAg seroconversion) and 57 healthy controls. One SNP and three haplotypes were identified after adjustment for age, sex, HBV DNA. The frequency of OAS3T/C heterozygotes is 52.2% in responders (R) and 38.2% in non-responders (NR), with an odds ratio (OR) of 1.511 (P = 0.018). For complete responders (CR) and NR, the OR reached 2.323(P = 0.023). Haplotype analyses revealed significant association between three OAS haplotypes and response to IFN-α treatment. Genotype combination and interaction between gene-gene analyses disclosed that there was a positive interaction between OAS2/OAS3 and OAS3/OASL, and the rate of OR was 2.46 (likelihood test, P = 0.004) and 4.46 (likelihood test, P = 0.004), respectively. Our results suggest that OAS gene variations may play an important role in response to IFN-α and provide a novel strategy for the resolution of HBV infection.

  7. The effect of oleic and palmitic acid on induction of steatosis and cytotoxicity on rat hepatocytes in primary culture.

    PubMed

    Moravcová, A; Červinková, Z; Kučera, O; Mezera, V; Rychtrmoc, D; Lotková, H

    2015-01-01

    In vitro models serve as a tool for studies of steatosis. Palmitic and oleic acids can induce steatosis in cultured hepatocytes. The aim of our study was to verify steatogenic and cytotoxic effects of palmitic acid (PA), oleic acid (OA) and their combinations as well as their impact on functional capacity of rat primary hepatocytes. Hepatocytes were exposed to OA or PA (0.125-2 mmol/l) or their combination at ratios of 3:1, 2:1 or 1:1 at the final concentrations of 0.5-1 mmol/l. Both OA and PA caused a dose-dependent increase in triacylglycerol content in hepatocytes. PA was more steatogenic at 0.25 and 0.5 mmol/l while OA at 0.75 and 1 mmol/l. PA exhibited a dose-dependent cytotoxic effect associated with ROS production, present markers of apoptosis and necrosis and a decrease in albumin production. OA induced a damage of the cytoplasmic membrane from 1 mM concentration. Mixture of OA and PA induced lower cytotoxicity with less weakened functional capacity than did PA alone. Extent of steatosis was comparable to that after exposure to OA alone. In conclusion, OA or combination of OA with PA is more suitable for simulation of simple steatosis than PA alone.

  8. The effect of low-molecular-weight organic acids on copper toxicity in E. fetida in an acute exposure system.

    PubMed

    Zhou, Chuifan; Huang, Meiying; Yu, Jiaoda; Li, Ying; Liu, Aiqin

    2017-02-18

    In the present study, the effects of low-molecular-weight organic acids (OAs) on the toxicity of copper (Cu) to the earthworm Eisenia fetida (E. fetida) were investigated in a simulated soil solution. We exposed E. fetida to soil solution containing Cu and a variety of OAs (acetic acid, oxalic acid, citric acid, and EDTA). We found that the addition of OAs reduced the toxicity of Cu to E. fetida, where the reduction was strongest in EDTA and weakest in acetic acid. These compounds decreased the mortality rate of E. fetida that were exposed to Cu and reduced levels of antioxidant enzymes and malondialdehyde to unexposed control levels. E. fetida were exposed to Cu with OAs had reduced Cu(2+), which were likely caused by Cu forming complexes with the OAs, reducing the availability of Cu. The presence of OAs also reduced Cu-induced damage on earthworm cellular ultrastructures and changed the subcellular distribution of Cu. These results demonstrated that OAs could reduce the toxicity, as well as the bioavailability, of heavy metals in soil solutions where both OAs and heavy metals often coexist.

  9. MEMANTINE ATTENUATES THE OKADAIC ACID INDUCED SHORT-TERM SPATIAL MEMORY IMPAIRMENT AND HIPPOCAMPAL CELL LOSS IN RATS.

    PubMed

    Dashniani, M; Chighladze, M; Burjanadze, M; Beselia, G; Kruashvili, L

    2016-03-01

    In the present study, the possible beneficial effect of memantine on the Okadaic Acid (OA) induced spatial short-term memory impairment was examined in spatial alternation task, and the neuroprotective potential of memantine on OA-induced structural changes in the hippocampus was evaluated by Nissl staining. OA was dissolved in artificial cerebrospinal fluid (aCSF) and injected intracerebroventriculary (ICV) 200 ng in a volume of 10 μl bilaterally. Vehicle control received aCSF ICV bilaterally. Control and OA injected rats were divided into 2 subgroups injected i.p. with saline or memantine (5 mg/kg). Memantine or saline were given daily for 13 days starting from the day of OA injection. Behavioral study showed that bilateral ICV microinjection of OA induced impairment in spatial short-term memory. Nissl staining in the present study showed that the ICV microinjection of OA significantly decreased the number of surviving pyramidal neurons in the CA1 region of the hippocampus. Chronic administration of memantine effectively attenuated OA induced spatial short-term memory impairment and the OA-induced neuropathological changes in the hippocampus. Therefore, ICV injection of OA can be used as an experimental model to study mechanisms of neurodegeneration and define novel therapeutics targets for AD pathology.

  10. Synergistic Effect of Oleanolic Acid on Aminoglycoside Antibiotics against Acinetobacter baumannii

    PubMed Central

    Shin, Bora; Park, Woojun

    2015-01-01

    Difficulties involved in treating drug-resistant pathogens have created a need for new therapies. In this study, we investigated the possibility of using oleanolic acid (OA), a natural pentacyclic triterpenoid, as a natural adjuvant for antibiotics against Acinetobacter baumannii. High concentrations of OA can kill cells, partly because it generates reactive oxygen species. Measurement of the fractional inhibitory concentration (FIC) for OA and time-kill experiments demonstrated that it only synergizes with aminoglycoside antibiotics (e.g., gentamicin, kanamycin). Other classes of antibiotics (e.g., ampicillin, rifampicin, norfloxacin, chloramphenicol, and tetracycline) have no interactions with OA. Microarray and quantitative reverse transcription-PCR analysis indicated that genes involved in ATP synthesis and cell membrane permeability, the gene encoding glycosyltransferase, peptidoglycan-related genes, phage-related genes, and DNA repair genes were upregulated under OA. OA highly induces the expression of adk, which encodes an adenylate kinase, and des6, which encodes a linoleoyl-CoA desaturase, and deletion of these genes increased FICs; these observations indicate that adk and des6 are involved in the synergism of OA with aminoglycosides. Data obtained using 8-anilino-1-naphthalenesulfonic acid, fluorescence-conjugated gentamicin, and membrane fatty acid analysis indicates that adk and des6 are involved in changes in membrane permeability. Proton-motive force and ATP synthesis tests show that those genes are also involved in energy metabolism. Taken together, our data show that OA boosts aminoglycoside uptake by changing membrane permeability and energy metabolism in A. baumannii. PMID:26360766

  11. Role of p53 in the cellular response following oleic acid accumulation in Chang liver cells.

    PubMed

    Park, Eun-Jung; Lee, Ah Young; Chang, Seung-Hee; Yu, Kyeong-Nam; Kim, Jae-Ho; Cho, Myung-Haing

    2014-01-03

    Abnormal accumulation of fatty acids triggers the harmful cellular response called lipotoxicity. In this study, we investigated the cellular response following accumulation of oleic acid (OA), a monounsaturated fatty acid, in human Chang liver cells. OA droplets were distributed freely in the cytoplasm and/or degraded within lysosomes. OA exposure increased ATP production and concomitantly dilated mitochondria. At 24h after OA exposure, cell viability decreased slightly and was coupled with a reduction in mitochondrial Ca(2+) concentration, the alteration in cell viability was also associated with the generation of reactive oxygen species and changes in the cell cycle. Moreover, OA treatment increased the expression of autophagy- and apoptotic cell death-related proteins in a dose-dependent manner. Furthermore, we investigated the role of p53, a tumor suppressor protein, in the cellular response elicited by OA accumulation. OA-induced changes in cell viability and ATP production were rescued to control levels when cells were pretreated with pifithrin-alpha (PTA), a p53 inhibitor. By contrast, the expressions of LC3-II and perilipin, proteins required for lipophagy, were down-regulated by PTA pretreatment. Taken together, our results suggest that p53 plays a key role in the cellular response elicited by OA accumulation in Chang liver cells.

  12. Anacardic Acid, Salicylic Acid, and Oleic Acid Differentially Alter Cellular Bioenergetic Function in Breast Cancer Cells.

    PubMed

    Radde, Brandie N; Alizadeh-Rad, Negin; Price, Stephanie M; Schultz, David J; Klinge, Carolyn M

    2016-11-01

    Anacardic acid is a dietary and medicinal phytochemical that inhibits breast cancer cell proliferation and uncouples oxidative phosphorylation (OXPHOS) in isolated rat liver mitochondria. Since mitochondrial-targeted anticancer therapy (mitocans) may be useful in breast cancer, we examined the effect of anacardic acid on cellular bioenergetics and OXPHOS pathway proteins in breast cancer cells modeling progression to endocrine-independence: MCF-7 estrogen receptor α (ERα)+ endocrine-sensitive; LCC9 and LY2 ERα+, endocrine-resistant, and MDA-MB-231 triple negative breast cancer (TNBC) cells. At concentrations similar to cell proliferation IC50 s, anacardic acid reduced ATP-linked oxygen consumption rate (OCR), mitochondrial reserve capacity, and coupling efficiency while increasing proton leak, reflecting mitochondrial toxicity which was greater in MCF-7 compared to endocrine-resistant and TNBC cells. These results suggest tolerance in endocrine-resistant and TNBC cells to mitochondrial stress induced by anacardic acid. Since anacardic acid is an alkylated 2-hydroxybenzoic acid, the effects of salicylic acid (SA, 2-hydroxybenzoic acid moiety) and oleic acid (OA, monounsaturated alkyl moiety) were tested. SA inhibited whereas OA stimulated cell viability. In contrast to stimulation of basal OCR by anacardic acid (uncoupling effect), neither SA nor OA altered basal OCR- except OA inhibited basal and ATP-linked OCR, and increased ECAR, in MDA-MB-231 cells. Changes in OXPHOS proteins correlated with changes in OCR. Overall, neither the 2-hydroxybenzoic acid moiety nor the monounsaturated alky moiety of anacardic acid is solely responsible for the observed mitochondria-targeted anticancer activity in breast cancer cells and hence both moieties are required in the same molecule for the observed effects. J. Cell. Biochem. 117: 2521-2532, 2016. © 2016 Wiley Periodicals, Inc.

  13. Identification of okadaic acid binding protein 2 in reconstituted sponge cell clusters from Halichondria okadai and its contribution to the detoxification of okadaic acid.

    PubMed

    Konoki, Keiichi; Okada, Kayo; Kohama, Mami; Matsuura, Hiroki; Saito, Kaori; Cho, Yuko; Nishitani, Goh; Miyamoto, Tomofumi; Fukuzawa, Seketsu; Tachibana, Kazuo; Yotsu-Yamashita, Mari

    2015-12-15

    Okadaic acid (OA) and OA binding protein 2 (OABP2) were previously isolated from the marine sponge Halichondria okadai. Because the amino acid sequence of OABP2 is completely different from that of protein phosphatase 2A, a well-known target of OA, we have been investigating the production and function of OABP2. In the present study, we hypothesized that OABP2 plays a role in the detoxification of OA in H. okadai and that the OA concentrations are in proportional to the OABP2 concentrations in the sponge specimens. Based on the OA concentrations and the OABP2 concentrations in the sponge specimens collected in various places and in different seasons, however, we could not determine a positive correlation between OA and OABP2. We then attempted to determine distribution of OA and OABP2 in the sponge specimen. When the mixture of dissociated sponge cells and symbiotic species were separated with various pore-sized nylon meshes, most of the OA and OABP2 was detected from the same 0-10 μm fraction. Next, when sponge cell clusters were prepared from a mixture of dissociated sponge cells and symbiotic species in the presence of penicillin and streptomycin, we identified the 18S rDNA of H. okadai and the gene of OABP2 in the analysis of genomic DNA but could not detect OA by LC-MS/MS. We thus concluded that the sponge cells express OABP2, and that OA was not apparently present in the sponge cells but could be colocalized with OABP2 in the sponge cells at a concentration less than the limit of detection.

  14. Who is Mr. HAMLET? Interaction of human alpha-lactalbumin with monomeric oleic acid.

    PubMed

    Knyazeva, Ekaterina L; Grishchenko, Valery M; Fadeev, Roman S; Akatov, Vladimir S; Permyakov, Sergei E; Permyakov, Eugene A

    2008-12-09

    A specific state of the human milk Ca(2+) binding protein alpha-lactalbumin (hLA) complexed with oleic acid (OA) prepared using an OA-pretreated ion-exchange column (HAMLET) triggers several cell death pathways in various tumor cells. The possibility of preparing a hLA-OA complex with structural and cytotoxic properties similar to those of the HAMLET but under solution conditions has been explored. The complex was formed by titration of hLA by OA at pH 8.3 up to OA critical micelle concentration. We have shown that complex formation strongly depends on calcium, ionic strength, and temperature; the optimal conditions were established. The spectrofluorimetrically estimated number of OA molecules irreversibly bound per hLA molecule (after dialysis of the OA-loaded preparation against water followed by lyophilization) depends upon temperature: 2.9 at 17 degrees C (native apo-hLA; resulting complex referred to as LA-OA-17 state) and 9 at 45 degrees C (thermally unfolded apo-hLA; LA-OA-45). Intrinsic tryptophan fluorescence measurements revealed substantially decreased thermal stability of Ca(2+)-free forms of HAMLET, LA-OA-45, and OA-saturated protein. The irreversibly bound OA does not affect the Ca(2+) association constant of the protein. Phase plot analysis of fluorimetric and CD data indicates that the OA binding process involves several hLA intermediates. The effective pseudoequilibrium OA association constants for Ca(2+)-free hLA were estimated. The far-UV CD spectra of Ca(2+)-free hLA show that all OA-bound forms of the protein are characterized by elevated content of alpha-helical structure. The various hLA-OA complexes possess similar cytotoxic activities against human epidermoid larynx carcinoma cells. Overall, the LA-OA-45 complex possesses physicochemical, structural, and cytotoxic properties closely resembling those of HAMLET. The fact that the HAMLET-like complex can be formed in aqueous solution makes the process of its preparation more transparent and

  15. The binding of okadaic acid analogs to recombinant OABP2.1 originally isolated from the marine sponge Halichondria okadai.

    PubMed

    Konoki, Keiichi; Onoda, Tatsuya; Furumochi, Sachie; Cho, Yuko; Yotsu-Yamashita, Mari; Yasumoto, Takeshi

    2013-11-01

    The binding between [24-(3)H]okadaic acid (OA) and a recombinant OA binding protein OABP2.1 was examined using various OA analog, including methyl okadaate, norokadanone, 7-deoxy OA, and 14,15-dihydro OA, 7-O-palmitoyl DTX1, to investigate the structure activity relationship. Among them, 7-O-palmitoyl DTX1, which is one of the diarrhetic shellfish poisoning (DSP) toxins identified in shellfish, displayed an IC50 for [24-(3)H]OA binding at 51±6.3nM (Mean±SD). In addition, a synthetic compound, N-pyrenylmethyl okadamide, exhibited its IC50 at 10±2.9nM (Mean±SD). These results suggested that the recombinant OABP2.1 and the N-pyrenylmethyl okadamide might be core substances in a novel assay for the DSP toxins.

  16. An evaluation of the anti-tumor efficacy of oleanolic acid-loaded PEGylated liposomes

    NASA Astrophysics Data System (ADS)

    Tang, Shengnan; Gao, Dawei; Zhao, Tingting; Zhou, Jing; Zhao, Xiaoning

    2013-06-01

    The effective delivery of oleanolic acid (OA) to the target site has several benefits in therapy for different pathologies. However, the delivery of OA is challenging due to its poor aqueous solubility. The study aims to evaluate the tumor inhibition effect of the PEGylated OA nanoliposome on the U14 cervical carcinoma cell line. In our previous study, OA was successfully encapsulated into PEGylated liposome with the modified ethanol injection method. Oral administration of PEGylated OA liposome was demonstrated to be more efficient in inhibiting xenograft tumors. The results of organ index indicated that PEG liposome exhibited higher anti-tumor activity and lower cytotoxicity. It was also found that OA and OA liposomes induced tumor cell apoptosis detected by flow cytometry. Furthermore, effects of OA on the morphology of tumor and other tissues were observed by hematoxylin and eosin staining. The histopathology sections did not show pathological changes in kidney or liver in tested mice. In contrast, there was a significant difference in tumor tissues between treatment groups and the negative control group. These observations imply that PEGylated liposomes seem to have advantages for cancer therapy in terms of effective delivery of OA.

  17. Optimized formulation of multivesicular liposomes loaded with oleanolic acid enhanced anticancer effect in vitro

    PubMed Central

    Wang, Yunlong; Luo, Yuling; Li, Chunhong; Zhang, Xiaoqin; Pi, Chao; Yu, Lu; Wang, Shurong; Zhong, Zhirong

    2017-01-01

    Invasion and metastasis are the main causes leading to the death of patients with hepatocellular carcinoma (HCC). Multivesicular liposomes loaded with oleanolic acid (OA-MVLs) have been well demonstrated to suppress survival, growth and angiogenesis of HCC cells. Emerging evidence demonstrates that OA was able to suppress the invasion of HCC cells by down-regulating myocyte enhancer factor-2. We hypothesized that the optimized OA-MVLs could inhibit the migration and invasion of HCC cells. In this study, we utilized central composite design and response surface methodology to assess the influence of some parameters on particle size and encapsulation efficiency and obtain the optimized formulation of OA-MVLs. Subsequently, the human HCC cell lines SMMC-7721 and HepG2 were treated with different doses of OA-MVLs and OA, respectively. Cellular survival, adhesion, migration and invasion in vitro were evaluated. We found that the optimized OA-MVLs significantly decreased the ability of HCC cells to adhere, migrate and invade in vitro. Furthermore, OA-MVLs significantly inhibited the survival of HCC cells at 160 µmol/L but showed no obvious inhibition effect on the cell vitality of normal liver cells. Our findings indicate that OA-MVLs did inhibit the cell survival, adhesion, invasion and metastasis of HCC cells in vitro. Although the involved mechanisms are still unclear, our findings can contribute to a better development of a preventive and therapeutic strategy for human HCC. PMID:28392677

  18. Oxalic acid: a prospective tool for reducing Varroa mite populations in package bees.

    PubMed

    Aliano, Nicholas P; Ellis, Marion D

    2009-08-01

    Numerous studies have investigated using oxalic acid (OA) to control Varroa mites in honey bee colonies. In contrast, techniques for treating package bees with OA have not been investigated. The goal of this study was to develop a protocol for using OA to reduce mite infestation in package bees. We made 97 mini packages of Varroa-infested adult bees. Each package contained 1,613 +/- 18 bees and 92 +/- 3 mites, and represented an experimental unit. We prepared a 2.8% solution of OA by mixing 35 g OA with 1 l of sugar water (sugar:water = 1:1; w:w). Eight treatments were assigned to the packages based on previous laboratory bioassays that characterized the acute contact toxicity of OA to mites and bees. We administered the treatments by spraying the OA solution directly on the bees through the mesh screen cage using a pressurized air brush and quantified mite and bee mortality over a 10-day period. Our results support applying an optimum volume of 3.0 ml of a 2.8% OA solution per 1,000 bees to packages for effective mite control with minimal adult bee mortality. The outcome of our research provides beekeepers and package bee shippers guidance for using OA to reduce mite populations in package bees.

  19. High Anti-Dengue Virus Activity of the OAS Gene Family Is Associated With Increased Severity of Dengue.

    PubMed

    Simon-Loriere, Etienne; Lin, Ren-Jye; Kalayanarooj, Sita Mint; Chuansumrit, Ampaiwan; Casademont, Isabelle; Lin, Shyr-Yi; Yu, Han-Pang; Lert-Itthiporn, Worachart; Chaiyaratana, Wathanee; Tangthawornchaikul, Nattaya; Tangnararatchakit, Kanchana; Vasanawathana, Sirijitt; Chang, Bi-Lan; Suriyaphol, Prapat; Yoksan, Sutee; Malasit, Prida; Despres, Philipe; Paul, Richard; Lin, Yi-Ling; Sakuntabhai, Anavaj

    2015-12-15

    Dengue is a mosquito-borne viral disease that afflicts millions of individuals worldwide every year. Infection by any of the 4 dengue virus (DENV) serotypes can result in a spectrum of disease severity. We investigated the impact of variants of interferon-regulated innate immunity genes with a potent antiviral effect on the outcome of DENV infection. We compared the effect of OAS gene family variants on 2 DENV serotypes in cell culture. While both OAS1-p42 and p46 showed antiviral activity against DENV-2, only OAS1-p42 presented anti-DENV-1 activity. Conversely, whereas both OAS3_S381 and R381 variants were able to block DENV-1 infection, the anti-DENV-2 activity observed for OAS3_S381 was largely lost for the R381 variant. By means of an allelic association study of a cohort of 740 patients with dengue, we found a protective effect of OAS3_R381 against shock (odds ratio [OR], 0.37; P < .001). This effect was due to DENV-2 infections (OR, 0.13; P = .007) but was absent for DENV-1, in accordance with the serotype-dependent OAS3 activity found in the functional study. Severe dengue has long been associated with a cytokine storm of unclear origin. This work identifies an early innate immunity process that could lead to the immune overreaction observed in severe dengue and could be triggered by a specific host genotype-pathogen genotype interaction.

  20. Sources, Properties, Aging, and Anthropogenic Influences on OA and SOA over the Southeast US and the Amazon duing SOAS, DC3, SEAC4RS, and GoAmazon

    EPA Science Inventory

    The SE US and the Amazon have large sources of biogenic VOCs, varying anthropogenic pollution impacts, and often poor organic aerosol (OA) model performance. Recent results on the sources, properties, aging, and impact of anthropogenic pollution on OA and secondary OA (SOA) over ...

  1. GPNMB/OA protein increases the invasiveness of human metastatic prostate cancer cell lines DU145 and PC3 through MMP-2 and MMP-9 activity

    SciTech Connect

    Fiorentini, Chiara; Bodei, Serena; Bedussi, Francesca; Fragni, Martina; Bonini, Sara Anna; Simeone, Claudio; Zani, Danilo; Berruti, Alfredo; Missale, Cristina; Memo, Maurizio; Spano, PierFranco; Sigala, Sandra

    2014-04-15

    Non-metastatic glycoprotein melanoma protein B (GPNMB), also known as osteoactivin (OA) is expressed in a wide array of tumors and represents an emerging target for drug development. In this study, we investigated the role of GPNMB/OA in the progression of human metastatic DU145 and PC3 prostate cancer cells. GPNMB/OA contribution in PCa malignant phenotype has been analyzed by small interfering RNA-induced GPNMB/OA silencing. We found that following GPNMB/OA silencing the migration capability of both DU145 and PC3 cells, evaluated by using in vitro invasivity assay, as well as the metalloproteinases MMP-2 and MMP-9 activity were equally strongly inhibited. By contrast knocking down GPNMB/OA weakly attenuated cell proliferation rate of DU145, an effect that paralleled with an increase number of apoptotic cells. However, PC3 cell growth seems to be not affected by GPNMB/OA. Together, these data reveal that GPNMB/OA acts as a critical molecular mediator promoting the acquisition of the more aggressive, pro-metastatic phenotype distinctive of human DU145 and PC3 cell lines. - Highlights: • GPNMB/OA expression correlates with DU145 and PC3 cells malignant phenotype. • GPNMB/OA silencing affects the migration capability of both DU145 and PC3 cells. • GPNMB/OA increases invasiveness by up-regulating MMPs activity. • GPNMB/OA promotes DU145 and PC3 cells progression into a more aggressive phenotype.

  2. Nrf2-dependent and -independent responses to nitro-fatty acids in human endothelial cells: identification of heat shock response as the major pathway activated by nitro-oleic acid.

    PubMed

    Kansanen, Emilia; Jyrkkänen, Henna-Kaisa; Volger, Oscar L; Leinonen, Hanna; Kivelä, Annukka M; Häkkinen, Sanna-Kaisa; Woodcock, Steven R; Schopfer, Francisco J; Horrevoets, Anton J; Ylä-Herttuala, Seppo; Freeman, Bruce A; Levonen, Anna-Liisa

    2009-11-27

    Electrophilic fatty acid derivatives, including nitrolinoleic acid and nitro-oleic acid (OA-NO(2)), can mediate anti-inflammatory and pro-survival signaling reactions. The transcription factor Nrf2, activated by electrophilic fatty acids, suppresses redox-sensitive pro-inflammatory gene expression and protects against vascular endothelial oxidative injury. It was therefore postulated that activation of Nrf2 by OA-NO(2) accounts in part for its anti-inflammatory actions, motivating the characterization of Nrf2-dependent and -independent effects of OA-NO(2) on gene expression using genome-wide transcriptional profiling. Control and Nrf2-small interfering RNA-transfected human endothelial cells were treated with vehicle, oleic acid, or OA-NO(2), and differential gene expression profiles were determined. Although OA-NO(2) significantly induced the expression of Nrf2-dependent genes, including heme oxygenase-1 and glutamate-cysteine ligase modifier subunit, the majority of OA-NO(2)-regulated genes were regulated by Nrf2-independent pathways. Moreover, gene set enrichment analysis revealed that the heat shock response is the major pathway activated by OA-NO(2), with robust induction of a number of heat shock genes regulated by the heat shock transcription factor. Inasmuch as the heat shock response mediates anti-inflammatory and cytoprotective actions, this mechanism is proposed to contribute to the protective cell signaling functions of nitro-fatty acids and other electrophilic fatty acid derivatives.

  3. Degradation of oxalic acid by the mycoparasite Coniothyrium minitans plays an important role in interacting with Sclerotinia sclerotiorum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Coniothyrium minitans is a mycoparasite of the phytopathogenic fungus Sclerotinia sclerotiorum. Sclerotinia sclerotiorum produces a virulence factor oxalic acid (OA) which is toxic to plants and also to C. minitans, and C. minitans detoxifies OA by degradation. In this study, two oxalate decarboxyla...

  4. Construction of low-cost, Mod-OA wood composite wind turbine blades

    NASA Technical Reports Server (NTRS)

    Lark, R. F.

    1983-01-01

    Two sixty-foot, low-cost, wood composite blades for service on 200 kW Mod-OA wind turbines were constructed. The blades were constructed of epoxy resin-bonded Douglas fir veneers for the leading edge sections, and paper honeycombcored, birch plywood faced panels for the afterbody sections. The blades were joined to the wind turbine hub by epoxy resin-bonded steel load take-off studs embedded into the root end of the blades. The blades were installed on the 200 kW Mod-OA wind turbine facility at Kahuku, Hawaii, The blades completed nearly 8,000 hours of operation over an 18 month period at an average power of 150 kW prior to replacement with another set of wood composite blades. The blades were replaced because of a corrosion failure of the steel shank on one stud. Inspections showed that the wood composite structure remained in excellent condition.

  5. Evaluation of an operating MOD-OA 200 kW wind turbine blade

    NASA Technical Reports Server (NTRS)

    Donham, R. E.

    1979-01-01

    Operating loads and structural damage were monitored during operation of the MOD-OA electric generating system. The turbine was damaged locally between stations 48 and 125 after 2.8 million rotations. Loads due to degraded yaw stiffness and fretting at rib station 48 were identified as primary to this distress. The repaired blades operated an additional 4.8 million rotations without problems.

  6. BOREAS TF-2 SSA-OA Tethersonde Meteorological and Ozone Data

    NASA Technical Reports Server (NTRS)

    Arnold, A. James; Mickle, Robert E.; Hall, Forrest G. (Editor); Huemmrich, Karl (Editor)

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study Tower Flux-2 (BOREAS TF-2) team collected meteorological and ozone measurements from instruments mounted below a tethered balloon. These data were collected at the Southern Study Area Old Aspen (SSA-OA) site to extend meteorological and ozone measurements made from the flux tower to heights of 300 m. The tethersonde operated during the fall of 1993 and the spring, summer, and fall of 1994. The data are available in tabular ASCII files.

  7. Altered function in cartilage derived mesenchymal stem cell leads to OA-related cartilage erosion

    PubMed Central

    Xia, Zenan; Ma, Pei; Wu, Nan; Su, Xinlin; Chen, Jun; Jiang, Chao; Liu, Sen; Chen, Weisheng; Ma, Bupeng; Yang, Xu; Ma, Yufen; Weng, Xisheng; Qiu, Guixing; Huang, Shishu; Wu, Zhihong

    2016-01-01

    A portion of osteoarthritis (OA) patients with total knee arthroplasty (TKA) had monocondylar destruction in medial femoral condyle, but healthy-appearant cartilage in lateral side. However, there is limited information concerning functional differences of cartilage derived mesenchymal stem cell (CMSC) between these two locations in the same donor and its possible role in the pathogenesis of OA. Cells isolated from the degraded cartilage in medial condyle and normal cartilage in lateral side from OA patients were identified with co-expressed markers CD105 and CD166 and confirmed as CMSCs by immunophenotype. The relative percentage, proliferation activity, multi-lineage differentiation potential and miRNA expression profile of CMSCs in two groups were compared by flow cytometry, CCK-8 assay, cytochemical staining, immunohistochemistry, real-time PCR and miRNA microarray analysis. Our study suggested that the percentage (10.61±6.97% vs. 18.44±9.97%, P<0.05) and proliferation rate (P<0.01) of CD105+/CD166+ CMSCs from the degraded cartilage were significantly reduced compared with those from the normal cartilage. CMSCs from the degraded cartilage also showed stronger osteogenic (P<0.05), weaker adipogenic (P<0.01), and comparable chondrogenic potential (P>0.05) during differentiation. MiR-31-5p and miR-424-5p were down regulated in CMSCs from the degraded cartilage. In conclusion, altered function such as reduced percentage and proliferation ability, as well as changes in differentiation profile of CMSC contributed to homeostasis imbalance, leading to OA-related cartilage erosion. Furthermore, regulatory networks of multiple miRNAs may be partially responsible for the dysfunction of CMSCs. PMID:27158337

  8. Expression of ocular albinism 1 (OA1), 3, 4- dihydroxy- L-phenylalanine (DOPA) receptor, in both neuronal and non-neuronal organs.

    PubMed

    Fukuda, Nobuhiko; Naito, Saki; Masukawa, Daiki; Kaneda, Moemi; Miyamoto, Hiroshi; Abe, Takaya; Yamashita, Yui; Endo, Itaru; Nakamura, Fumio; Goshima, Yoshio

    2015-03-30

    Oa1 is the casual gene for ocular albinism-1 in humans. The gene product OA1, alternatively designated as GPR143, belongs to G-protein coupled receptors. It has been reported that OA1 is a specific receptor for 3, 4-dihydroxy- L-phenylalanine (DOPA) in retinal pigmental epithelium where DOPA facilitates the pigmentation via OA1 stimulation. We have recently shown that OA1 mediates DOPA-induced depressor response in rat nucleus tractus solitarii. However, the distribution and function of OA1 in other regions are largely unknown. We have generated oa1 knockout mice and examined OA1 expression in both neuronal and non-neuronal tissues by immunohistochemical analyses using anti-mouse OA1 monoclonal antibodies. In the telencephalon, OA1 was expressed in cerebral cortex and hippocampus. Predominant expression of OA1 was observed in the pyramidal neurons in these regions. OA1 was also expressed in habenular nucleus, hypothalamus, substantia nigra, and medulla oblongata. The expression of OA1 in the nucleus tractus solitarii of medulla oblongata may support the reduction of blood pressure by the microinjection of DOPA into this region. Outside of the nervous system, OA1 was expressed in heart, lung, liver, kidney and spleen. Abundant expression was observed in the renal tubules and the splenic capsules. These peripheral regions are innervated by numerous sympathetic nerve endings. In addition, substantia nigra contains a large population of dopaminergic neurons. Thus, the immunohistochemical analyses suggest that OA1 may modulate the monoaminergic functions in both peripheral and central nervous systems.

  9. Okadaic Acid: More than a Diarrheic Toxin

    PubMed Central

    Valdiglesias, Vanessa; Prego-Faraldo, María Verónica; Pásaro, Eduardo; Méndez, Josefina; Laffon, Blanca

    2013-01-01

    Okadaic acid (OA) is one of the most frequent and worldwide distributed marine toxins. It is easily accumulated by shellfish, mainly bivalve mollusks and fish, and, subsequently, can be consumed by humans causing alimentary intoxications. OA is the main representative diarrheic shellfish poisoning (DSP) toxin and its ingestion induces gastrointestinal symptoms, although it is not considered lethal. At the molecular level, OA is a specific inhibitor of several types of serine/threonine protein phosphatases and a tumor promoter in animal carcinogenesis experiments. In the last few decades, the potential toxic effects of OA, beyond its role as a DSP toxin, have been investigated in a number of studies. Alterations in DNA and cellular components, as well as effects on immune and nervous system, and even on embryonic development, have been increasingly reported. In this manuscript, results from all these studies are compiled and reviewed to clarify the role of this toxin not only as a DSP inductor but also as cause of alterations at the cellular and molecular levels, and to highlight the relevance of biomonitoring its effects on human health. Despite further investigations are required to elucidate OA mechanisms of action, toxicokinetics, and harmful effects, there are enough evidences illustrating its toxicity, not related to DSP induction, and, consequently, supporting a revision of the current regulation on OA levels in food. PMID:24184795

  10. Nitrooleic Acid Attenuates Lipid Metabolic Disorders and Liver Steatosis in DOCA-Salt Hypertensive Mice.

    PubMed

    Wang, Haiping; Sun, Jing; Jia, Zhanjun; Yang, Tianxin; Xu, Liang; Zhao, Bing; Yu, Kezhou; Wang, Rong

    2015-01-01

    Nitrooleic acid (OA-NO2) is endogenous ligands for peroxisome proliferator-activated receptors. The present study was aimed at investigating the beneficial effects of OA-NO2 on the lipid metabolism and liver steatosis in deoxycorticosterone acetate- (DOCA-) salt induced hypertensive mice model. Male C57BL/6 mice were divided to receive DOCA-salt plus OA-NO2 or DOCA-salt plus vehicle and another group received neither DOCA-salt nor OA-NO2 (control group). After 3-week treatment with DOCA-salt plus 1% sodium chloride in drinking fluid, the hypertension was noted; however, OA-NO2 had no effect on the hypertension. In DOCA-salt treated mice, the plasma triglyceride and total cholesterol levels were significantly increased compared to control mice, and pretreatment with OA-NO2 significantly reduced these parameters. Further, the histopathology of liver exhibited more lipid distribution together with more serious micro- and macrovesicular steatosis after DOCA-salt treatment and that was consistent with liver tissue triglyceride and nonesterified fatty acids (NEFA) content. The mice pretreated with OA-NO2 showed reduced liver damage accompanied with low liver lipid content. Moreover, the liver TBARS, together with the expressions of gp91phox and p47phox, were parallelly decreased. These findings indicated that OA-NO2 had the protective effect on liver injury against DOCA-salt administration and the beneficial effect could be attributed to its antihyperlipidemic activities.

  11. Effects of oleic acid on distinct populations of neurons in the hypothalamic arcuate nucleus are dependent on extracellular glucose levels.

    PubMed

    Wang, R; Cruciani-Guglielmacci, C; Migrenne, S; Magnan, C; Cotero, V E; Routh, V H

    2006-03-01

    Pharmacological manipulation of fatty acid metabolism in the hypothalamic arcuate nucleus (ARC) alters energy balance and glucose homeostasis. Thus, we tested the hypotheses that distinctive populations of ARC neurons are oleic acid (OA) sensors that exhibit a glucose dependency, independent of whether some of these OA sensors are also glucose-sensing neurons. We used patch-clamp recordings to investigate the effects of OA on ARC neurons in brain slices from 14- to 21-day-old Sprague-Dawley (SD) rats. Additionally, we recorded spontaneous discharge rate in ARC neurons in 8-wk-old fed and fasted SD rats in vivo. Patch-clamp studies showed that in 2.5 mM glucose 12 of 94 (13%) ARC neurons were excited by 2 microM OA (OA-excited or OAE neurons), whereas six of 94 (6%) were inhibited (OA-inhibited2.5 or OAI2.5 neurons). In contrast, in 0.1 mM glucose, OA inhibited six of 20 (30%) ARC neurons (OAI0.1 neurons); none was excited. None of the OAI0.1 neurons responded to OA in 2.5 mM glucose. Thus OAI2.5 and OAI0.1 neurons are distinct. Similarly, in seven of 20 fed rats (35%) the overall response was OAE-like, whereas in three of 20 (15%) it was OAI-like. In contrast, in fasted rats only OAI-like response were observed (three of 15; 20%). There was minimal overlap between OA-sensing neurons and glucose-sensing neurons. In conclusion, OA regulated three distinct subpopulations of ARC neurons in a glucose-dependent fashion. These data suggest that an interaction between glucose and fatty acids regulates OA sensing in ARC neurons.

  12. Transglutaminase 2 is a Marker of Chondrocyte Hypertrophy and Osteoarthritis Severity in the Hartley Guinea Pig Model of Knee OA

    PubMed Central

    Huebner, Janet L; Johnson, Kristen A.; Kraus, Virginia B.; Terkeltaub, Robert A.

    2011-01-01

    Objective The transglutaminase (TG) isoenzyme TG2, which catalyzes protein cross-linking via transamidation, influences healing phenotype in multiple forms of tissue injury. Moreover, TG2 knockout suppresses cartilage destruction but promotes osteophyte formation in instability-induced mouse knee OA. TG2 is marker of growth plate chondrocyte hypertrophy. Moreover, TG2 secreted by chondrocytes acts in part by promoting chondrocyte maturation to hypertrophy, a differentiation state linked with MMP-13 expression and disease progression in OA. Moreover, glucosamine, which is currently under investigation as an OA therapy, binds and inhibits TG2. Here, we examined TG2 as a potential marker of cartilage hypertrophy in the spontaneous guinea pig model of OA. Methods Synovial fluid ELISA and cartilage Immunohistochemistry and quantitative RT-PCR, were used to examine TG2 expression and TG transamidation-catalyzed isopeptide bonds. Results TG isopeptide bonds and TG2 were most abundant in articular cartilage in early knee OA. TG2 expression was robust at sites of early but not established osteophytes. Synovial fluid TG2 correlated with knee OA total histological score (r=0.47, p=0.01), as did medial tibial plateau cartilage TG2 mRNA (r=1.0, p=0.003). At 12 months of age, medial tibial plateau cartilage TG2 mRNA expression rose markedly in association with elevated type X collagen, as well as ADAMTS-5, and MMP-13 expression, changes not shared in age-matched Strain 13 guinea pigs that are less susceptible to knee OA. Conclusion Hartley guinea pig knee TG2 expression associates with enhanced articular chondrocyte hypertrophy and is a biomarker of OA severity. PMID:19328881

  13. Oxalic acid capped iron oxide nanorods as a sensing platform.

    PubMed

    Sharma, Anshu; Baral, Dinesh; Bohidar, H B; Solanki, Pratima R

    2015-08-05

    A label free impedimetric immunosensor has been fabricated using protein bovine serum albumin (BSA) and monoclonal antibodies against Vibrio cholerae (Ab) functionalized oxalic acid (OA) capped iron oxide (Fe3O4) nanorods for V. cholerae detection. The structural and morphological studies of Fe3O4 and OA-Fe3O4, were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and dynamic light scattering (DLS) techniques. The average crystalline size of Fe3O4, OA-Fe3O4 nanorods were obtained as about 29±1 and 39±1nm, respectively. The hydrodynamic radius of nanorods is found as 116nm (OA-Fe3O4) and 77nm (Fe3O4) by DLS measurement. Cytotoxicity of Fe3O4 and OA-Fe3O4 nanorods has been investigated in the presence of human epithelial kidney (HEK) cell line 293 using MTT assay. The cell viability and proliferation studies reveal that the OA-Fe3O4 nanorods facilitate cell growth. The results of electrochemical response studies of the fabricated BSA/Ab/OA-Fe2O3/ITO immunosensor exhibits good linearity in the range of 12.5-500ng mL(-1) with low detection limit of 0.5ng mL(-1), sensitivity 0.1Ωng(-1)ml(-1)cm(-2) and reproducibility more than 11 times.

  14. Crystal Structure of Okadaic Acid Binding Protein 2.1: A Sponge Protein Implicated in Cytotoxin Accumulation.

    PubMed

    Ehara, Haruhiko; Makino, Marie; Kodama, Koichiro; Konoki, Keiichi; Ito, Takuhiro; Sekine, Shun-ichi; Fukuzawa, Seketsu; Yokoyama, Shigeyuki; Tachibana, Kazuo

    2015-07-06

    Okadaic acid (OA) is a marine polyether cytotoxin that was first isolated from the marine sponge Halichondria okadai. OA is a potent inhibitor of protein serine/threonine phosphatases (PP) 1 and 2A, and the structural basis of phosphatase inhibition has been well investigated. However, the role and mechanism of OA retention in the marine sponge have remained elusive. We have solved the crystal structure of okadaic acid binding protein 2.1 (OABP2.1) isolated from H. okadai; it has strong affinity for OA and limited sequence homology to other proteins. The structure revealed that OABP2.1 consists of two α-helical domains, with the OA molecule deeply buried inside the protein. In addition, the global fold of OABP2.1 was unexpectedly similar to that of aequorin, a jellyfish photoprotein. The presence of structural homologues suggested that, by using similar protein scaffolds, marine invertebrates have developed diverse survival systems adapted to their living environments.

  15. ERK inhibition sensitizes cancer cells to oleanolic acid-induced apoptosis through ERK/Nrf2/ROS pathway.

    PubMed

    Liu, Jia; Ma, Leina; Chen, Xiao; Wang, Jianxun; Yu, Tao; Gong, Ying; Ma, Aiguo; Zheng, Lanhong; Liang, Hui

    2016-06-01

    Oleanolic acid (OA) is a natural triterpenoid that is widely distributed in edible and medicinal plants. OA exerts anti-tumor activity on a wide range of cancer cells primarily through inducing apoptosis. Dysregulated ERK signaling is closely complicated in the biology of cancer, such as metastasis, proliferation, and survival, and it can be activated by various stimuli. In this study, we found that OA induced the activation of ERK in cancer cells. ERK activation compromised the apoptosis induced by OA. Blocking ERK activation by U0126 or siRNAs was able to potentiate the pro-apoptotic activity of OA on cancer cells. OA was shown to promote ERK-dependent Nrf2 expression in cancer cells, and in turn, Nrf2 expression was able to suppress OA-induced ROS generation. Blockade of Nrf2 expression was able to increase ROS levels and apoptotic death in cancer cells. In conclusion, we provided evidences that ERK activation is a mechanism underlying the resistance of cancer cells to OA-induced apoptosis and targeting ERK is a promising strategy to enhance the anti-tumor efficacy of OA.

  16. Structural characterization of more potent alternatives to HAMLET, a tumoricidal complex of α-lactalbumin and oleic acid.

    PubMed

    Nemashkalova, Ekaterina L; Kazakov, Alexei S; Khasanova, Leysan M; Permyakov, Eugene A; Permyakov, Sergei E

    2013-09-10

    HAMLET is a complex of human α-lactalbumin (hLA) with oleic acid (OA) that kills various tumor cells and strains of Streptococcus pneumoniae. More potent protein-OA complexes were previously reported for bovine α-lactalbumin (bLA) and β-lactoglobulin (bLG), and pike parvalbumin (pPA), and here we explore their structural features. The concentration dependencies of the tryptophan fluorescence of hLA, bLA, and bLG complexes with OA reveal their disintegration at protein concentrations below the micromolar level. Chemical cross-linking experiments provide evidence that association with OA shifts the distribution of oligomeric forms of hLA, bLA, bLG, and pPA toward higher-order oligomers. This effect is confirmed for bLA and bLG using the dynamic light scattering method, while pPA is shown to associate with OA vesicles. Like hLA binding, OA binding increases the affinity of bLG for small unilamellar dipalmitoylphosphatidylcholine vesicles, while pPA efficiently binds to the vesicles irrespective of OA binding. The association of OA with bLG and pPA increases their α-helix and cross-β-sheet content and resistance to enzymatic proteolysis, which is indicative of OA-induced protein structuring. The lack of excess heat sorption during melting of bLG and pPA in complex with OA and the presence of a cooperative thermal transition at the level of their secondary structure suggest that the OA-bound forms of bLG and pPA lack a fixed tertiary structure but exhibit a continuous thermal transition. Overall, despite marked differences, the HAMLET-like complexes that were studied exhibit a common feature: a tendency toward protein oligomerization. Because OA-induced oligomerization has been reported for other proteins, this phenomenon is inherent to many proteins.

  17. The biological activities of protein/oleic acid complexes reside in the fatty acid.

    PubMed

    Fontana, Angelo; Spolaore, Barbara; Polverino de Laureto, Patrizia

    2013-06-01

    A complex formed by human α-lactalbumin (α-LA) and oleic acid (OA), named HAMLET, has been shown to have an apoptotic activity leading to the selective death of tumor cells. In numerous publications it has been reported that in the complex α-LA is monomeric and adopts a partly folded or "molten globule" state, leading to the idea that partly folded proteins can have "beneficial effects". The protein/OA molar ratio initially has been reported to be 1:1, while recent data have indicated that the OA-complex is given by an oligomeric protein capable of binding numerous OA molecules per protein monomer. Proteolytic fragments of α-LA, as well as other proteins unrelated to α-LA, can form OA-complexes with biological activities similar to those of HAMLET, thus indicating that a generic protein can form a cytotoxic complex under suitable experimental conditions. Moreover, even the selective tumoricidal activity of HAMLET-like complexes has been questioned. There is recent evidence that the biological activity of long chain unsaturated fatty acids, including OA, can be ascribed to their effect of perturbing the structure of biological membranes and consequently the function of membrane-bound proteins. In general, it has been observed that the cytotoxic effects exerted by HAMLET-like complexes are similar to those reported for OA alone. Overall, these findings can be interpreted by considering that the protein moiety does not have a toxic effect on its own, but merely acts as a solubilising agent for the inherently toxic fatty acid.

  18. Microencapsulation of okadaic acid as a tool for studying the accumulation of DSP toxins in mussels.

    PubMed

    Rossignoli, Araceli E; Fernández, David; Acosta, Carmen P; Blanco, Juan

    2011-02-01

    The possibility and effectiveness of microencapsulation of okadaic acid (OA) in gelatin-acacia microcapsules has been studied. The encapsulation efficiency was higher than 33%. The microcapsules were shown to be very stable, not leaching more than 9% of the encapsulated OA in a 20-h period. OA from the microcapsules was absorbed by the mussels very efficiently, accumulating--after 3 days of feeding and one of depuration--65% of the OA in microcapsules and 22% of the total OA used at the beginning of the microencapsulation process. These efficiencies and the possibility of encapsulating single DSP toxins and derivatives constitute a valuable tool for the study of the accumulation and biotransformation of DSP toxins in bivalves.

  19. Alterations of amino acid metabolism in osteoarthritis: its implications for nutrition and health.

    PubMed

    Li, Yusheng; Xiao, Wenfeng; Luo, Wei; Zeng, Chao; Deng, Zhenhan; Ren, Wenkai; Wu, Guoyao; Lei, Guanghua

    2016-04-01

    Osteoarthritis (OA) is a common form of arthritis in humans. It has long been regarded as a non-inflammatory disease, but a degree of inflammation is now recognized as being a vital inducer of subpopulation of OA. Besides inflammation, the establishment and development of OA are associated with alterations in metabolism and profiles of amino acids (AA), including glutamate- and arginine-family AA as well as their related metabolites (e.g., creatinine, hydroxyproline, γ-aminobutyrate, dimethylarginines and homoarginine). Functional AA (e.g., glutamine, arginine, glutamate, glycine, proline, and tryptophan) have various benefits (i.e., anti-inflammation and anti-oxidation) in treatment of inflammation-associated diseases, including OA. Thus, these AA have potential as immunomodulatory nutrients for patients with inflammation-induced OA.

  20. Evolution of organic aerosol mass spectra upon heating: implications for OA phase and partitioning behavior

    SciTech Connect

    UC Davis; Cappa, Christopher D.; Wilson, Kevin R.

    2010-10-28

    Vacuum Ultraviolet (VUV) photoionization mass spectrometry has been used to measure the evolution of chemical composition for two distinct organic aerosol types as they are passed through a thermodenuder at different temperatures. The two organic aerosol types considered are primary lubricating oil (LO) aerosol and secondary aerosol from the alpha-pinene + O3 reaction (alphaP). The evolution of the VUV mass spectra for the two aerosol types with temperature are observed to differ dramatically. For LO particles, the spectra exhibit distinct changes with temperature in which the lower m/z peaks, corresponding to compounds with higher vapor pressures, disappear more rapidly than the high m/z peaks. In contrast, the alphaP aerosol spectrum is essentially unchanged by temperature even though the particles experience significant mass loss due to evaporation. The variations in the LO spectra are found to be quantitatively in agreement with expectations from absorptive partitioning theory whereas the alphaP spectra suggest that the evaporation of alphaP derived aerosol appears to not be governed by partitioning theory. We postulate that this difference arises from the alphaP particles existing as in a glassy state instead of having the expected liquid-like behavior. To reconcile these observations with decades of aerosol growth measurements, which indicate that OA formation is described by equilibrium partitioning, we present a conceptual model wherein the secondary OA is formed and then rapidly converted from an absorbing form to a non-absorbing form. The results suggest that although OA growth may be describable by equilibrium partitioning theory, the properties of organic aerosol once formed may differ significantly from the properties determined in the equilibrium framework.

  1. Microprocessor control system for 200-kilowatt Mod-OA wind turbines

    NASA Technical Reports Server (NTRS)

    Nyland, T. W.; Birchenough, A. G.

    1982-01-01

    The microprocessor system and program used to control the operation of the 200-kW Mod-OA wind turbines is described. The system is programmed to begin startup and shutdown sequences automatically and to control yaw motion. Rotor speed and power output are controlled with integral and proportional control of the blade pitch angle. Included in the report are a description of the hardware and a discussion of the software programming technique. A listing of the PL/M software program is given.

  2. BOREAS TF-2 SSA-OA Tower Flux, Meteorological, and Precipitation Data

    NASA Technical Reports Server (NTRS)

    Neumann, Harold; Mickle, Robert; Staebler, Ralf; Hall, Forrest G. (Editor); Huemmrich, Karl (Editor)

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study Tower Flux-2 (BOREAS TF-2) team collected energy, carbon dioxide, water vapor, and momentum flux data above the canopy and in profiles through the canopy, along with meteorological data at the BOREAS Southern Study Area-Old Aspen (SSA-OA) site. Above-canopy measurements began in early February and ran through mid-September of 1994. Measurements were collected over a longer period of 1994 than most BOREAS flux sites. Daily precipitation data from several gauges were also collected. The data are available in tabular ASCII files.

  3. Role of ocular albinism type 1 (OA1) GPCR in Asian gypsy moth development and transcriptional expression of heat-shock protein genes.

    PubMed

    Sun, LiLi; Wang, ZhiYing; Wu, HongQu; Liu, Peng; Zou, ChuanShan; Xue, XuTing; Cao, ChuanWang

    2016-01-01

    The ocular albinism type 1 gene, named OA1, is a coding pigment cell-specific G protein-coupled receptor exclusively localized in intracellular organelles. However, the function of OA1 in insects remains generally unknown. In the present study, we explore for the first time the function of LdOA1 in the Asian gypsy moth, Lymantria dispar. To identify the function of LdOA1 gene in the development and growth of the Asian gypsy moth, the LdOA1 gene in third instar larvae was knocked down by RNAi. Compared with the controls, the knockdown of LdOA1 increased larval mortality but did not significantly affect their utilization of nutrition. Moreover, LdOA1 was stably transformed into the third chromosome of Drosophila melanogaster. The LdOA1 gene in the transformed D. melanogaster modulated the expression of heat-shock protein (hsp) and increased the expression of hsp genes under deltamethrin stress, which indicates that LdOA1 is involved in the regulation of hsp gene expression. These results deepen our understanding of the molecular function of OA1 in insects.

  4. Effect of okadaic acid on cultured clam heart cells: involvement of MAPkinase pathways.

    PubMed

    Hanana, Houda; Talarmin, Hélène; Pennec, Jean-Pierre; Droguet, Mickael; Morel, Julie; Dorange, Germaine

    2012-12-15

    Okadaic acid (OA) is one of the main diarrhetic shellfish poisoning toxins and a potent inhibitor of protein phosphatases 1 and 2A. The downstream signal transduction pathways following the protein phosphatase inhibition are still unknown and the results of most of the previous studies are often conflicting. The aim of the present study was to evaluate the effects of OA on heart clam cells and to analyse its possible mechanisms of action by investigating the signal transduction pathways involved in OA cytotoxicity. We showed that OA at 1 µM after 24 h of treatment induces disorganization of the actin cytoskeleton, rounding and detachment of fibroblastic cells. Moreover, treatment of heart cells revealed a sequential activation of MAPK proteins depending on the OA concentration. We suggest that the duration of p38 and JNK activation is a critical factor in determining cell apoptosis in clam cardiomyocytes. In the opposite, ERK activation could be involved in cell survival. The cell death induced by OA is a MAPK modulated pathway, mediated by caspase 3-dependent mechanism. OA was found to induce no significant effect on spontaneous beating rate or inward L-type calcium current in clam cardiomyocytes, suggesting that PP1 was not inhibited even by the highest dose of OA.

  5. A New Oleanolic Acid Derivative against CCl4-Induced Hepatic Fibrosis in Rats

    PubMed Central

    Xiang, Hongjun; Han, Yaotian; Zhang, Yuzhong; Yan, Wenqiang; Xu, Bing; Chu, Fuhao; Xie, Tianxin; Jia, Menglu; Yan, Mengmeng; Zhao, Rui; Wang, Penglong; Lei, Haimin

    2017-01-01

    A novel hepatoprotective oleanolic acid derivative, 3-oxours-oleana-9(11), 12-dien-28-oic acid (Oxy-Di-OA), has been reported. In previous studies, we found that Oxy-Di-OA presented the anti-HBV (Hepatitis B Virus) activity (IC50 = 3.13 µg/mL). Remarkably, it is superior to lamivudine in the inhibition of the rebound of the viral replication rate. Furthermore, Oxy-Di-OA showed good performance of anti-HBV activity in vivo. Some studies showed that liver fibrosis may affiliate with HBV gene mutations. In addition, the anti-hepatic fibrosis activity of Oxy-Di-OA has not been studied. Therefore, we evaluated the protective effect of Oxy-Di-OA against carbon tetrachloride (CCl4)-induced liver injury in rats. Daily intraperitoneally administration of Oxy-Di-OA prevented the development of CCl4-induced liver fibrosis, which was evidenced by histological study and immunohistochemical analysis. The entire experimental protocol lasted nine weeks. Oxy-Di-OA significantly suppressed the increases of plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels (p < 0.05). Furthermore, Oxy-Di-OA could prevent expression of transforming growth factor β1 (TGF-β1). It is worth noting that the high-dose group Oxy-Di-OA is superior to bifendate in elevating hepatic function. Compared to the model group, Oxy-Di-OA in the high-dose group and low-dose group can significantly reduce the liver and spleen indices (p < 0.05). The acute toxicity test showed that LD50 and a 95% confidence interval (CIs) value of Oxy-Di-OA were 714.83 mg/kg and 639.73–798.73 mg/kg via intraperitoneal injection in mice, respectively. The LD50 value of Oxy-Di-OA exceeded 2000 mg/kg via gavage in mice. In addition, a simple and rapid high performance liquid chromatography-ultraviolet (HPLC-UV) method was developed and validated to study the pharmacokinetic characteristics of the compound. After single-dose oral administration, time to reach peak concentration of Oxy-Di-OA (Cmax = 8.18

  6. A graphene-based electrochemical competitive immunosensor for the sensitive detection of okadaic acid in shellfish

    NASA Astrophysics Data System (ADS)

    Eissa, Shimaa; Zourob, Mohammed

    2012-11-01

    A novel graphene-based voltammetric immunosensor for sensitive detection of okadaic acid (OA) was developed. A simple and efficient electrografting method was utilized to functionalize graphene-modified screen-printed carbon electrodes (GSPE) by the electrochemical reduction of in situ generated 4-carboxyphenyl diazonium salt in acidic aqueous solution. Next, the okadaic acid antibody was covalently immobilized on the carboxyphenyl modified graphene electrodes via carbodiimide chemistry. Square wave voltammetry (SWV) was used to investigate the stepwise assembly of the immunosensor. A competitive assay between OA and a fixed concentration of okadaic acid-ovalbumin conjugate (OA-OVA) for the immobilized antibodies was employed for the detection of okadaic acid. The decrease of the [Fe(CN)6]3-/4- reduction peak current in the square wave voltammetry for various concentrations of okadaic acid was used for establishing the calibration curve. A linear relationship between the SWV peak current difference and OA concentration was obtained up to ~5000 ng L-1. The developed immunosensor allowed a detection limit of 19 ng L-1 of OA in PBS buffer. The matrix effect studied with spiked shellfish tissue extracts showed a good percentage of recovery and the method was also validated with certified reference mussel samples.A novel graphene-based voltammetric immunosensor for sensitive detection of okadaic acid (OA) was developed. A simple and efficient electrografting method was utilized to functionalize graphene-modified screen-printed carbon electrodes (GSPE) by the electrochemical reduction of in situ generated 4-carboxyphenyl diazonium salt in acidic aqueous solution. Next, the okadaic acid antibody was covalently immobilized on the carboxyphenyl modified graphene electrodes via carbodiimide chemistry. Square wave voltammetry (SWV) was used to investigate the stepwise assembly of the immunosensor. A competitive assay between OA and a fixed concentration of okadaic acid

  7. Location and binding mechanism of an ESIPT probe 3-hydroxy-2-naphthoic acid in unsaturated fatty acid bound serum albumins.

    PubMed

    Ghorai, Shyamal Kr; Tripathy, Debi Ranjan; Dasgupta, Swagata; Ghosh, Sanjib

    2014-02-05

    The binding site and the binding mechanism of 3-hydroxy-2-naphthoic acid (3HNA) in oleic acid (OA) bound serum albumins (bovine serum albumin (BSA) and human serum albumin (HSA)) have been determined using steady state and time resolved emission of tryptophan residues (Trp) in proteins and the ESIPT emission of 3HNA. Time resolved anisotropy of the probe 3HNA and low temperature phosphorescence of Trp residues of BSA in OA bound BSA at 77K reveals a drastic change of the binding site of 3HNA in the ternary system compared to that in the free protein. 3HNA binds near Trp213 in the ternary system whereas 3HNA binds near Trp134 in the free protein. The structure of OA bound BSA generated using docking methodology exhibits U-bend configuration of all bound OA. The docked pose of 3HNA in the free protein and in OA bound albumins (ternary systems) and the concomitant perturbation of the structure of proteins around the binding region of 3HNA corroborate the enhanced ESIPT emission of 3HNA and the energy transfer efficiency from the donor Trp213 of BSA to 3HNA acceptor in 3HNA-OA-BSA system.

  8. Rotationally sampled wind characteristics and correlations with MOD-OA wind turbine response

    SciTech Connect

    George, R.L.; Connell, J.R.

    1984-09-01

    This report presents results of a comprehensive wind and wind turbine measurement program: the Clayton, New Mexico, vertical plane array/MOD-OA project. In this experiment, the turbulent wind was measured for a large array of fixed anemometers located two blade diameters upwind of a 200-kW horizontal-axis wind turbine (HAWT). Simultaneously, key wind turbine response parameters were also measured. The first of two major objectives of this experiment was to determine the turbulent wind, rotationally sampled to emulate the motion of the wind turbine blade, for the range of different wind speeds and stability classes actually experienced by the wind turbine. The second major objective was to correlate this rotationally sampled wind with the wind turbine blade stress and power, in order to assess the usefulness of the wind measurements for wind turbine loads testing a prediction. Time series of rotationally sampled winds and wind turbine blade bending moments and power were converted to frequency spectra using Fourier transform techniques. These spectra were used as the basis for both qualitative and quantitative comparisons among the various cases. A quantitative comparison between the rotationally sampled wind input and blade bending response was made, using the Fourier spectra to estimate the blade transfer function. These transfer functions were then used to calculate an approximate damping coefficient for the MOD-OA fiberglass blade.

  9. The mammalian 2'-5' oligoadenylate synthetase gene family: evidence for concerted evolution of paralogous Oas1 genes in Rodentia and Artiodactyla.

    PubMed

    Perelygin, Andrey A; Zharkikh, Andrey A; Scherbik, Svetlana V; Brinton, Margo A

    2006-10-01

    Multiple 2'-5' oligoadenylate (2-5A) synthetases are important components of innate immunity in mammals. Gene families encoding these proteins have previously been studied mainly in humans and mice. To reconstruct the evolution of this gene family in mammals, a search for additional 2-5A synthetase genes was performed in rat, cattle, pig, and dog. Twelve 2'-5' oligoadenylate synthetase (Oas) genes were identified in the rat genome, including eight Oas1 genes, two Oas1 pseudogenes, single copies of Oas2 and Oas3, and two Oas-like genes, Oasl1 and Oasl2. Four OAS genes were detected in the pig genome and five OAS genes were found in both the cattle and dog genomes. An OAS3 gene was not found in either the cattle or the pig genome. While two tandemly duplicated OAS-like (OASL) genes were identified in the dog genome, only a single OASL orthologue was found in both the cattle and the pig genomes. The bovine and porcine OASL genes contain premature stop codons and encode truncated proteins, which lack the typical C-terminal double ubiquitin domains. The cDNA sequences of the rat, cattle, pig, and dog OAS genes were amplified, sequenced and compared with each other and with those in the human, mouse, horse, and chicken genomes. Evidence of concerted evolution of paralogous 2'-5' oligoadenylate synthetase 1 genes was obtained in rodents (Rodentia) and even-toed ungulates (Artiodactyla). Calculations using the nonparametric Kolmogorov-Smirnov test suggested that the homogenization of paralogous OAS1 sequences was due to gene conversion rather than stabilizing selection.

  10. Ca(2+)-dependent permeabilization of mitochondria and liposomes by palmitic and oleic acids: a comparative study.

    PubMed

    Belosludtsev, Konstantin N; Belosludtseva, Natalia V; Agafonov, Alexey V; Astashev, Maxim E; Kazakov, Alexey S; Saris, Nils-Erik L; Mironova, Galina D

    2014-10-01

    In the present work, we examine and compare the effects of saturated (palmitic) and unsaturated (oleic) fatty acids in relation to their ability to cause the Ca(2+)-dependent membrane permeabilization. The results obtained can be summarized as follows. (1) Oleic acid (OA) permeabilizes liposomal membranes at much higher concentrations of Ca(2+) than palmitic acid (PA): 1mM versus 100μM respectively. (2) The OA/Ca(2+)-induced permeabilization of liposomes is not accompanied by changes in the phase state of lipid bilayer, in contrast to what is observed with PA and Ca(2+). (3) The addition of Ca(2+) to the PA-containing vesicles does not change their size; in the case of OA, it leads to the appearance of larger and smaller vesicles, with larger vesicles dominating. This can be interpreted as a result of fusion and fission of liposomes. (4) Like PA, OA is able to induce a Ca(2+)-dependent high-amplitude swelling of mitochondria, yet it requires higher concentrations of Ca(2+) (30 and 100μM for PA and OA respectively). (5) In contrast to PA, OA is unable to cause the Ca(2+)-dependent high-amplitude swelling of mitoplasts, suggesting that the cause of OA/Ca(2+)-induced permeability transition in mitochondria may be the fusion of the inner and outer mitochondrial membranes. (6) The presence of OA enhances PA/Ca(2+)-induced permeabilization of liposomes and mitochondria. The paper discusses possible mechanisms of PA/Ca(2+)- and OA/Ca(2+)-induced membrane permeabilization, the probability of these mechanisms to be realized in the cell, and their possible physiological role.

  11. Oleanolic acid inhibits cell survival and proliferation of prostate cancer cells in vitro and in vivo through the PI3K/Akt pathway.

    PubMed

    Li, Xuechao; Song, Yarong; Zhang, Peng; Zhu, Hongxue; Chen, Lifeng; Xiao, Yajun; Xing, Yifei

    2016-06-01

    Oleanolic acid (OA) is a naturally occurring pentacyclic triterpenoid and possesses diverse pharmacological activities, including anti-cancer effects that have been confirmed in multiple types of human cancers. However, the potential effect of natural OA on human prostate cancer is still unclear. The present study aimed to explore whether and how OA exerted anti-cancer effects in prostate cancer. Our data showed that OA inhibited cell viability and proliferation, and promoted cell apoptosis and G0/G1 phase cell cycle arrest in prostate cancer PC-3, DU145, and LNCaP cells, in a dose-dependent manner. In addition, OA was found to regulate the expression levels of apoptosis-related and cell cycle-related proteins, as well as the activity of PI3K/Akt pathway, in a dose-dependent manner. Mechanistically, our data revealed that OA exerted anti-cancer effects in vitro in PC-3 and DU145 cells by repressing the PI3K/Akt pathway. In agreement, OA also suppressed the tumor growth of PC-3 cells in vivo via inhibition of the PI3K/Akt pathway. In conclusion, our findings demonstrate the anti-cancer properties of OA in prostate cancer cells, both in vitro and in vivo, and provide the experimental evidence for the use of OA as an adjuvant agent for prostate cancer patients.

  12. Synthesis of oleic acid functionalized Fe3O4 magnetic nanoparticles and studying their interaction with tumor cells for potential hyperthermia applications.

    PubMed

    Jadhav, Neena V; Prasad, Amresh I; Kumar, Amit; Mishra, R; Dhara, Sangita; Babu, K R; Prajapat, C L; Misra, N L; Ningthoujam, R S; Pandey, B N; Vatsa, R K

    2013-08-01

    In the present study, oleic acid (OA) functionalized Fe3O4 magnetic nanoparticles (MN) were synthesized following modified wet method of MN synthesis. The optimum amount of OA required for capping of MN and the amount of bound and unbound/free OA was determined by thermogravimetric analysis (TGA). Further, we have studied the effect of water molecules, associated with MN, on the variation in their induction heating ability under alternating current (AC) magnetic field conditions. We have employed a new approach to achieve dispersion of OA functionalized MN (MN-OA) in aqueous medium using sodium carbonate, which improves their biological applicability. Interactions amongst MN, OA and sodium carbonate were studied by Fourier transform infrared spectroscopy (FT-IR). Intracellular localization of MN-OA was studied in mouse fibrosarcoma cells (WEHI-164) by prussian blue staining and confocal laser scanning microscopy (CLSM) using nile blue A as a fluorescent probe. Results showed MN-OA to be interacting mainly with the cell membrane. Their hyperthermic killing ability was evaluated in WEHI-164 cells by trypan blue method. Cells treated with MN-OA in combination with induction heating showed decreased viability as compared to respective induction heating controls. These results were supported by altered cellular morphology after treatment of MN-OA in combination with induction heating. Further, the magnitude of apoptosis was found to be ~5 folds higher in cells treated with MN-OA in combination with induction heating as compared to untreated control. These results suggest the efficacy of MN-OA in killing of tumor cells by cellular hyperthermia.

  13. Oleanolic Acid Prevents Increase in Blood Pressure and Nephrotoxicity in Nitric Oxide Dependent Type of Hypertension in Rats

    PubMed Central

    Bachhav, Sagar S.; Bhutada, Mukesh S.; Patil, Sachin P.; Sharma, Kinjal S.; Patil, Savita D.

    2015-01-01

    Background: Recently, we have reported antihypertensive activity of oleanolic acid (OA) in glucocorticoid-induced hypertension with restoration of nitric oxide (NO) level. However, the involvement of NO-releasing action of OA was unclear. Objective: To explore antihypertensive activity of OA in Nω-nitro-L-arginine methyl ester (L-NAME) hypertensive rats wherein NO is completely blocked, which would allow exploring the possibility of involvement of NO-releasing action of OA. Materials and Methods: Five groups of rats were investigated as normal control, L-NAME (40 mg/kg/day), L-NAME + enalapril (15 mg/kg/day), L-NAME + l-arginine (100 mg/kg/day), and L-NAME + OA (60 mg/kg/day) for 4 weeks. The systolic blood pressure, body weight, and heart rate were measured weekly for 4 weeks. Serum nitrate/nitrite (NOx) level, urine electrolytes concentration, cardiac mass index, and serum creatinine level were determined followed by organ histopathology. Results: OA and enalapril delayed the rise in blood pleasure following L-NAME administration. Decreased serum NOx level was not significantly increased with any of the treatment. OA produced a small, though nonsignificant, increase in the NOx level. L-NAME administration did not affect cardiac mass index. There was an increase in serum creatinine upon L-NAME administration which was prevented by OA. Decreased urine volume, urine sodium and potassium were reversed by OA. Conclusion: These results suggest that the antihypertensive effect of OA in L-NAME hypertension is due to diuresis and nephroprotection. However, OA has nonsignificantly affected the NO levels. PMID:26692754

  14. Bat Mx1 and Oas1, but not Pkr are highly induced by bat interferon and viral infection.

    PubMed

    Zhou, Peng; Cowled, Christopher; Wang, Lin-Fa; Baker, Michelle L

    2013-01-01

    Bats harbour many emerging and re-emerging viruses, several of which are highly pathogenic in other mammals but cause no diseases in bats. As the interferon (IFN) response represents a first line of defence against viral infection, the ability of bats to control viral replication may be linked to the activation of the IFN system. The three most studied antiviral IFN-stimulated genes (ISGs) in other mammals; Pkr, Mx1 and Oas1 were examined in our model bat species, Pteropus alecto. Our results demonstrate that the three ISGs from P. alecto are highly conserved in their functional domains and promoter elements compared to corresponding genes from other mammals. However, P. alecto Oas1 contains two IFN-stimulated response elements (ISRE) in its promoter region compared with the single ISRE present in human OAS1 which may lead to higher IFN inducibility of the bat gene. Both Oas1 and Mx1 were induced in a highly IFN-dependent manner following stimulation with IFN or synthetic double-strand RNA (dsRNA) whereas Pkr showed evidence of being induced in an IFN-independent manner. Furthermore, bat Oas1 appeared to be the most inducible of the three ISGs following either IFN stimulation or viral infection, providing evidence that Oas1 may play a more important role in antiviral activity in bats compared with Mx1 or Pkr. Our results have important implications for the different roles of ISGs in bats and provide the first step in understanding the role of these molecules in the ability of bats to coexist with viruses.

  15. Sasa quelpaertensis and p-coumaric acid attenuate oleic acid-induced lipid accumulation in HepG2 cells.

    PubMed

    Kim, Jeong-Hwan; Kang, Seong-Il; Shin, Hye-Sun; Yoon, Seon-A; Kang, Seung-Woo; Ko, Hee-Chul; Kim, Se-Jae

    2013-01-01

    In this study, we examined the effects of Jeju dwarf bamboo (Sasa quelpaertensis Nakai) extract (JBE) and p-coumaric acid (CA) on oleic acid (OA)-induced lipid accumulation in HepG2 cells. JBE and CA increased the phosphorylation of AMP-activated protein kinase (AMPK), and acetyl-CoA carboxylase (ACC) and the expression of carnitine palmitoyl transferase 1a (CPT1a) in OA-treated HepG2 cells. Additionally, these compounds decreased sterol regulatory element-binding protein-1c (SREBP-1c), fatty acid synthase (FAS), and OA-induced lipid accumulation, suggesting that JBE and CA modulate lipid metabolism in HepG2 cells via the AMPK activation pathway.

  16. The MOD-OA 200 kilowatt wind turbine generator design and analysis report

    NASA Technical Reports Server (NTRS)

    Andersen, T. S.; Bodenschatz, C. A.; Eggers, A. G.; Hughes, P. S.; Lampe, R. F.; Lipner, M. H.; Schornhorst, J. R.

    1980-01-01

    The project requirements, approach, system description, design requirements, design, analysis, system tests, installation safety considerations, failure modes and effects analysis, data acquisition, and initial performance for the MOD-OA 200 kw wind turbine generator are discussed. The components, the rotor, driven train, nacelle equipment, yaw drive mechanism and brake, tower, foundation, electrical system, and control systems are presented. The rotor includes the blades, hub and pitch change mechanism. The drive train includes the low speed shaft, speed increaser, high speed shaft, and rotor brake. The electrical system includes the generator, switchgear, transformer, and utility connection. The control systems are the blade pitch, yaw, and generator control, and the safety system. Manual, automatic, and remote control and Dynamic loads and fatigue are analyzed.

  17. Neandertal origin of genetic variation at the cluster of OAS immunity genes.

    PubMed

    Mendez, Fernando L; Watkins, Joseph C; Hammer, Michael F

    2013-04-01

    Analyses of ancient DNA from extinct humans reveal signals of at least two independent hybridization events in the history of non-African populations. To date, there are very few examples of specific genetic variants that have been rigorously identified as introgressive. Here, we survey DNA sequence variation in the OAS gene cluster on chromosome 12 and provide strong evidence that a haplotype extending for ~185 kb introgressed from Neandertals. This haplotype is nearly restricted to Eurasians and is estimated to have diverged from the Neandertal sequence ~125 kya. Despite the potential for novel functional variation, the observed frequency of this haplotype is consistent with neutral introgression. This is the second locus in the human genome, after STAT2, carrying distinct haplotypes that appear to have introgressed separately from both Neandertals and Denisova.

  18. Differential stress reaction of human colon cells to oleic-acid-stabilized and unstabilized ultrasmall iron oxide nanoparticles

    PubMed Central

    Schütz, Catherine A; Staedler, Davide; Crosbie-Staunton, Kieran; Movia, Dania; Chapuis Bernasconi, Catherine; Kenzaoui, Blanka Halamoda; Prina-Mello, Adriele; Juillerat-Jeanneret, Lucienne

    2014-01-01

    Therapeutic engineered nanoparticles (NPs), including ultrasmall superparamagnetic iron oxide (USPIO) NPs, may accumulate in the lower digestive tract following ingestion or injection. In order to evaluate the reaction of human colon cells to USPIO NPs, the effects of non-stabilized USPIO NPs (NS-USPIO NPs), oleic-acid-stabilized USPIO NPs (OA-USPIO NPs), and free oleic acid (OA) were compared in human HT29 and CaCo2 colon epithelial cancer cells. First the biophysical characteristics of NS-USPIO NPs and OA-USPIO NPs in water, in cell culture medium supplemented with fetal calf serum, and in cell culture medium preconditioned by HT29 and CaCo2 cells were determined. Then, stress responses of the cells were evaluated following exposure to NS-USPIO NPs, OA-USPIO NPs, and free OA. No modification of the cytoskeletal actin network was observed. Cell response to stress, including markers of apoptosis and DNA repair, oxidative stress and degradative/autophagic stress, induction of heat shock protein, or lipid metabolism was determined in cells exposed to the two NPs. Induction of an autophagic response was observed in the two cell lines for both NPs but not free OA, while the other stress responses were cell- and NP-specific. The formation of lipid vacuoles/droplets was demonstrated in HT29 and CaCo2 cells exposed to OA-USPIO NPs but not to NS-USPIO NPs, and to a much lower level in cells exposed to equimolar concentrations of free OA. Therefore, the induction of lipid vacuoles in colon cells exposed to OA utilized as a stabilizer for USPIO NPs is higly amplified compared to free OA, and is not observed in the absence of this lipid in NS-USPIO NPs. PMID:25092978

  19. Global genetic variation at OAS1 provides evidence of archaic admixture in Melanesian populations.

    PubMed

    Mendez, Fernando L; Watkins, Joseph C; Hammer, Michael F

    2012-06-01

    Recent analysis of DNA extracted from two Eurasian forms of archaic human shows that more genetic variants are shared with humans currently living in Eurasia than with anatomically modern humans in sub-Saharan Africa. Although these genome-wide average measures of genetic similarity are consistent with the hypothesis of archaic admixture in Eurasia, analyses of individual loci exhibiting the signal of archaic introgression are needed to test alternative hypotheses and investigate the admixture process. Here, we provide a detailed sequence analysis of the innate immune gene OAS1, a locus with a divergent Melanesian haplotype that is very similar to the Denisova sequence from the Altai region of Siberia. We resequenced a 7-kb region encompassing the OAS1 gene in 88 individuals from six Old World populations (San, Biaka, Mandenka, French Basque, Han Chinese, and Papua New Guineans) and discovered previously unknown and ancient genetic variation. The 5' region of this gene has unusual patterns of diversity, including 1) higher levels of nucleotide diversity in Papuans than in sub-Saharan Africans, 2) very deep ancestry with an estimated time to the most recent common ancestor of >3 myr, and 3) a basal branching pattern with Papuan individuals on either side of the rooted network. A global geographic survey of >1,500 individuals showed that the divergent Papuan haplotype is nearly restricted to populations from eastern Indonesia and Melanesia. Polymorphic sites within this haplotype are shared with the draft Denisova genome over a span of ∼90 kb and are associated with an extended block of linkage disequilibrium, supporting the hypothesis that this haplotype introgressed from an archaic source that likely lived in Eurasia.

  20. Ocean acidification increases copper toxicity differentially in two key marine invertebrates with distinct acid-base responses

    PubMed Central

    Lewis, Ceri; Ellis, Robert P.; Vernon, Emily; Elliot, Katie; Newbatt, Sam; Wilson, Rod W.

    2016-01-01

    Ocean acidification (OA) is expected to indirectly impact biota living in contaminated coastal environments by altering the bioavailability and potentially toxicity of many pH-sensitive metals. Here, we show that OA (pH 7.71; pCO2 1480 μatm) significantly increases the toxicity responses to a global coastal contaminant (copper ~0.1 μM) in two keystone benthic species; mussels (Mytilus edulis) and purple sea urchins (Paracentrotus lividus). Mussels showed an extracellular acidosis in response to OA and copper individually which was enhanced during combined exposure. In contrast, urchins maintained extracellular fluid pH under OA by accumulating bicarbonate but exhibited a slight alkalosis in response to copper either alone or with OA. Importantly, copper-induced damage to DNA and lipids was significantly greater under OA compared to control conditions (pH 8.14; pCO2 470 μatm) for both species. However, this increase in DNA-damage was four times lower in urchins than mussels, suggesting that internal acid-base regulation in urchins may substantially moderate the magnitude of this OA-induced copper toxicity effect. Thus, changes in metal toxicity under OA may not purely be driven by metal speciation in seawater and may be far more diverse than either single-stressor or single-species studies indicate. This has important implications for future environmental management strategies. PMID:26899803

  1. The cytotoxicity of BAMLET complexes is due to oleic acid and independent of the α-lactalbumin component

    PubMed Central

    Delgado, Yamixa; Morales-Cruz, Moraima; Figueroa, Cindy M.; Hernández-Román, José; Hernández, Glinda; Griebenow, Kai

    2015-01-01

    Lipid–protein complexes comprised of oleic acid (OA) non-covalently coupled to human/bovine α-lactalbumin, named HAMLET/BAMLET, display cytotoxic properties against cancer cells. However, there is still a substantial debate about the role of the protein in these complexes. To shed light into this, we obtained three different BAMLET complexes using varying synthesis conditions. Our data suggest that to form active BAMLET particles, OA has to reach critical micelle concentration with an approximate diameter of 250 nm. Proteolysis experiments on BAMLET show that OA protects the protein and is probably located on the surface, consistent with a micelle-like structure. Native or unfolded α-lactalbumin without OA lacked any tumoricidal activity. In contrast, OA alone killed cancer cells with the same efficiency at equimolar concentrations as its formulation as BAMLET. Our data show unequivocally that the cytotoxicity of the BAMLET complex is exclusively due to OA and that OA alone, when formulated as a micelle, is as toxic as the BAMLET complex. The contradictory literature results on the cytotoxicity of BAMLET might be explained by our finding that it was imperative to sonicate the samples to obtain toxic OA. PMID:26101738

  2. Apis mellifera octopamine receptor 1 (AmOA1) expression in antennal lobe networks of the honey bee (Apis mellifera) and fruit fly (Drosophila melanogaster)

    PubMed Central

    Sinakevitch, Irina T.; Smith, Adrian N.; Locatelli, Fernando; Huerta, Ramon; Bazhenov, Maxim; Smith, Brian H.

    2013-01-01

    Octopamine (OA) underlies reinforcement during appetitive conditioning in the honey bee and fruit fly, acting via different subtypes of receptors. Recently, antibodies raised against a peptide sequence of one honey bee OA receptor, AmOA1, were used to study the distribution of these receptors in the honey bee brain (Sinakevitch et al., 2011). These antibodies also recognize an isoform of the AmOA1 ortholog in the fruit fly (OAMB, mushroom body OA receptor). Here we describe in detail the distribution of AmOA1 receptors in different types of neurons in the honey bee and fruit fly antennal lobes. We integrate this information into a detailed anatomical analysis of olfactory receptor neurons (ORNs), uni- and multi-glomerular projection neurons (uPNs, and mPNs) and local interneurons (LNs) in glomeruli of the antennal lobe. These neurons were revealed by dye injection into the antennal nerve, antennal lobe, medial and lateral antenno-protocerbral tracts (m-APT and l-APT), and lateral protocerebral lobe (LPL) by use of labeled cell lines in the fruit fly or by staining with anti-GABA. We found that ORN receptor terminals and uPNs largely do not show immunostaining for AmOA1. About seventeen GABAergic mPNs leave the antennal lobe through the ml-APT and branch into the LPL. Many, but not all, mPNs show staining for AmOA1. AmOA1 receptors are also in glomeruli on GABAergic processes associated with LNs. The data suggest that in both species one important action of OA in the antennal lobe involves modulation of different types of inhibitory neurons via AmOA1 receptors. We integrated this new information into a model of circuitry within glomeruli of the antennal lobes of these species. PMID:24187534

  3. Apis mellifera octopamine receptor 1 (AmOA1) expression in antennal lobe networks of the honey bee (Apis mellifera) and fruit fly (Drosophila melanogaster).

    PubMed

    Sinakevitch, Irina T; Smith, Adrian N; Locatelli, Fernando; Huerta, Ramon; Bazhenov, Maxim; Smith, Brian H

    2013-01-01

    Octopamine (OA) underlies reinforcement during appetitive conditioning in the honey bee and fruit fly, acting via different subtypes of receptors. Recently, antibodies raised against a peptide sequence of one honey bee OA receptor, AmOA1, were used to study the distribution of these receptors in the honey bee brain (Sinakevitch et al., 2011). These antibodies also recognize an isoform of the AmOA1 ortholog in the fruit fly (OAMB, mushroom body OA receptor). Here we describe in detail the distribution of AmOA1 receptors in different types of neurons in the honey bee and fruit fly antennal lobes. We integrate this information into a detailed anatomical analysis of olfactory receptor neurons (ORNs), uni- and multi-glomerular projection neurons (uPNs, and mPNs) and local interneurons (LNs) in glomeruli of the antennal lobe. These neurons were revealed by dye injection into the antennal nerve, antennal lobe, medial and lateral antenno-protocerbral tracts (m-APT and l-APT), and lateral protocerebral lobe (LPL) by use of labeled cell lines in the fruit fly or by staining with anti-GABA. We found that ORN receptor terminals and uPNs largely do not show immunostaining for AmOA1. About seventeen GABAergic mPNs leave the antennal lobe through the ml-APT and branch into the LPL. Many, but not all, mPNs show staining for AmOA1. AmOA1 receptors are also in glomeruli on GABAergic processes associated with LNs. The data suggest that in both species one important action of OA in the antennal lobe involves modulation of different types of inhibitory neurons via AmOA1 receptors. We integrated this new information into a model of circuitry within glomeruli of the antennal lobes of these species.

  4. Oleanolic acid and its synthetic derivatives for the prevention and therapy of cancer: Preclinical and clinical evidence

    PubMed Central

    Shanmugam, Muthu K.; Dai, Xiaoyun; Kumar, Alan Prem; Tan, Benny KH; Sethi, Gautam; Bishayee, Anupam

    2014-01-01

    Oleanolic acid (OA, 3β-hydroxyolean-12-en-28-oic acid) is a ubiquitous pentacyclic multifunctional triterpenoid, widely found in several dietary and medicinal plants. Natural and synthetic OA derivatives can modulate multiple signaling pathways including nuclear factor-κB, AKT, signal transducer and activator of transcription 3, mammalian target of rapamycin, caspases, intercellular adhesion molecule 1, vascular endothelial growth factor, and poly (ADP-ribose) polymerase in a variety of tumor cells. Importantly, synthetic derivative of OA, 2-cyano-3,12-dioxoolean-1,9-dien-28-oic acid (CDDO), and its C-28 methyl ester (CDDO-Me) and C28 imidazole (CDDO-Im) have demonstrated potent antiangiogenic and antitumor activities in rodent cancer models. These agents are presently under evaluation in phase I studies in cancer patients. This review summarizes the diverse molecular targets of OA and its derivatives and also provides clear evidence on their promising potential in preclinical and clinical situations. PMID:24486850

  5. Determination of lipophilic toxins by LC/MS/MS: single-laboratory validation.

    PubMed

    Villar-González, Adriano; Rodríguez-Velasco, María Luisa; Gago-Martínez, Ana

    2011-01-01

    An LC/MS/MS method has been developed, assessed, and intralaboratory-validated for the analysis of the lipophilic toxins currently regulated by European Union legislation: okadaic acid (OA) and dinophysistoxins 1 and 2, including their ester forms; azaspiracids 1, 2, and 3; pectenotoxins 1 and 2; yessotoxin (YTX), and the analogs 45 OH-YTX, Homo YTX, and 45 OH-Homo YTX; as well as for the analysis of 13-desmetil-spirolide C. The method consists of duplicate sample extraction with methanol and direct analysis of the crude extract without further cleanup or concentration. Ester forms of OA and dinophysistoxins are detected as the parent ions after alkaline hydrolysis of the extract. The validation process of this method was performed using both fortified and naturally contaminated samples, and experiments were designed according to International Organization for Standardization, International Union of Pure and Applied Chemistry, and AOAC guidelines. With the exception of YTX in fortified samples, RSDr below 15% and RSDR were below 25%. Recovery values were between 77 and 95%, and LOQs were below 60 microg/kg. These data together with validation experiments for recovery, selectivity, robustness, traceability, and linearity, as well as uncertainty calculations, are presented in this paper.

  6. Blade design and operating experience on the MOD-OA 200 kW wind turbine at Clayton, New Mexico

    NASA Technical Reports Server (NTRS)

    Linscott, B. S.; Shaltens, R. K.

    1979-01-01

    Two 60 foot long aluminum wind turbine blades were operated for over 3000 hours on the MOD-OA wind turbine. The first signs of blade structural damage were observed after 400 hours of operation. Details of the blade design, loads, cost, structural damage, and repair are discussed.

  7. Epigenetic regulation of OAS2 shows disease-specific DNA methylation profiles at individual CpG sites

    PubMed Central

    Gu, Xiaolian; Boldrup, Linda; Coates, Philip J.; Fahraeus, Robin; Nylander, Elisabet; Loizou, Christos; Olofsson, Katarina; Norberg-Spaak, Lena; Gärskog, Ola; Nylander, Karin

    2016-01-01

    Epigenetic modifications are essential regulators of biological processes. Decreased DNA methylation of OAS2 (2′-5′-Oligoadenylate Synthetase 2), encoding an antiviral protein, has been seen in psoriasis. To provide further insight into the epigenetic regulation of OAS2, we performed pyrosequencing to detect OAS2 DNA methylation status at 11 promoter and first exon located CpG sites in psoriasis (n = 12) and two common subtypes of squamous cell carcinoma (SCC) of the head and neck: tongue (n = 12) and tonsillar (n = 11). Compared to corresponding controls, a general hypomethylation was seen in psoriasis. In tongue and tonsillar SCC, hypomethylation was found at only two CpG sites, the same two sites that were least demethylated in psoriasis. Despite differences in the specific residues targeted for methylation/demethylation, OAS2 expression was upregulated in all conditions and correlations between methylation and expression were seen in psoriasis and tongue SCC. Distinctive methylation status at four successively located CpG sites within a genomic area of 63 bp reveals a delicately integrated epigenetic program and indicates that detailed analysis of individual CpGs provides additional information into the mechanisms of epigenetic regulation in specific disease states. Methylation analyses as clinical biomarkers need to be tailored according to disease-specific sites. PMID:27572959

  8. Ocean acidification effects on Caribbean scleractinian coral calcification using a recirculating system: a novel approach to OA research

    EPA Science Inventory

    Projected increases in ocean pCO2 levels are likely to affect calcifying organisms more rapidly and to a greater extent than any other marine organisms. The effects of ocean acidification (OA) has been documented in numerous species of corals in both laboratory and field studies....

  9. Polymorphisms of interferon-inducible genes OAS-1 and MxA associated with SARS in the Vietnamese population.

    PubMed

    Hamano, Emi; Hijikata, Minako; Itoyama, Satoru; Quy, Tran; Phi, Nguyen Chi; Long, Hoang Thuy; Ha, Le Dang; Ban, Vo Van; Matsushita, Ikumi; Yanai, Hideki; Kirikae, Fumiko; Kirikae, Teruo; Kuratsuji, Tadatoshi; Sasazuki, Takehiko; Keicho, Naoto

    2005-04-22

    We hypothesized that host antiviral genes induced by type I interferons might affect the natural course of severe acute respiratory syndrome (SARS). We analyzed single nucleotide polymorphisms (SNPs) of 2',5'-oligoadenylate synthetase 1 (OAS-1), myxovirus resistance-A (MxA), and double-stranded RNA-dependent protein kinase in 44 Vietnamese SARS patients with 103 controls. The G-allele of non-synonymous A/G SNP in exon 3 of OAS-1 gene showed association with SARS (p=0.0090). The G-allele in exon 3 of OAS-1 and the one in exon 6 were in strong linkage disequilibrium and both of them were associated with SARS infection. The GG genotype and G-allele of G/T SNP at position -88 in the MxA gene promoter were found more frequently in hypoxemic group than in non-hypoxemic group of SARS (p=0.0195). Our findings suggest that polymorphisms of two IFN-inducible genes OAS-1 and MxA might affect susceptibility to the disease and progression of SARS at each level.

  10. 41 CFR 102-85.70 - Are the standard OA terms appropriate for non-cancelable space?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... terms appropriate for non-cancelable space? 102-85.70 Section 102-85.70 Public Contracts and Property... PROPERTY 85-PRICING POLICY FOR OCCUPANCY IN GSA SPACE Occupancy Agreement § 102-85.70 Are the standard OA terms appropriate for non-cancelable space? Yes, most of the standard terms apply; however, the right...

  11. Luminescence properties of LaF{sub 3}:Ce nanoparticles encapsulated by oleic acid

    SciTech Connect

    Kim, Jaewoo; Lee, Jun-Hyung; An, Hyejin; Lee, Jungkuk; Park, Seong-Hee; Seo, Young-Soo; Miller, William H.

    2014-09-15

    Highlights: • In-situ hydrophobization of water dispersible LaF{sub 3}:Ce nanoparticles was achieved. • Oleic acid surface modification of the nanoparticles was verified by IR spectra. • Quantum yields of LaF{sub 3}:Ce and OA-LaF{sub 3}:Ce nanoparticles were evaluated. • Quantum yields of LaF{sub 3}:Ce are strongly dependent on OA surface modification. - Abstract: Cerium ions doped lanthanum fluoride (LaF{sub 3}:Ce) nanopowder as well as LaF{sub 3}:Ce nanopowder whose surfaces was modified by oleic acid (OA) were synthesized by using an in-situ hydrothermal process under the various doping concentrations. Based on the XRD spectra and TEM images, it was confirmed that the crystalline structured hexagonal LaF{sub 3}:Ce nanopowder was synthesized. Oleic acid was efficient for conversion of the water dispersible LaF{sub 3}:Ce nanoparticles to hydrophobic ones. Surface modification was verified by FTIR absorption spectrum as well as TEM images, showing no agglomeration between 5 and 10 nm scaled particles. Photoluminescence based on 5d ⟶ 4f electronic transition of cerium ions excited at λ{sub ex} ∼256 nm for both neat and OA encapsulated LaF{sub 3}:Ce nanoparticles decreases as the cerium concentration increases, while the quantum yields of OA encapsulated nanoparticles were much lower than the neat particles due to low photon transmittance of OA at the range longer than ∼350 nm.

  12. Sex-Specific Protection of Osteoarthritis by Deleting Cartilage Acid Protein 1

    PubMed Central

    Ge, Xianpeng; Ritter, Susan Y.; Tsang, Kelly; Shi, Ruirui; Takei, Kohtaro; Aliprantis, Antonios O.

    2016-01-01

    Cartilage acidic protein 1 (CRTAC1) was recently identified as an elevated protein in the synovial fluid of patients with osteoarthritis (OA) by a proteomic analysis. This gene is also upregulated in both human and mouse OA by transcriptomic analysis. The objective of this study was to characterize the expression and function of CRTAC1 in OA. Here, we first confirm the increase of CRTAC1 in cartilage biopsies from OA patients undergoing joint replacement by real-time PCR and immunohistochemistry. Furthermore, we report that proinflammatory cytokines interleukin-1beta and tumor necrosis factor alpha upregulate CRTAC1 expression in primary human articular chondrocytes and synovial fibroblasts. Genetic deletion of Crtac1 in mice significantly inhibited cartilage degradation, osteophyte formation and gait abnormalities of post-traumatic OA in female, but not male, animals undergoing the destabilization of medial meniscus (DMM) surgery. Taken together, CRTAC1 is upregulated in the osteoarthritic joint and directly induced in chondrocytes and synovial fibroblasts by pro-inflammatory cytokines. This molecule is necessary for the progression of OA in female mice after DMM surgery and thus represents a potential therapy for this prevalent disease, especially for women who demonstrate higher rates and more severe OA. PMID:27415616

  13. Histone-dependent IgG conservation in octanoic acid precipitation and its mechanism.

    PubMed

    Chen, Quan; Toh, Phyllicia; Sun, Yue; Latiff, Sarah Maria Abdul; Hoi, Aina; Xian, Mo; Zhang, Haibo; Nian, Rui; Zhang, Wei; Gagnon, Pete

    2016-12-01

    Octanoic acid (OA) precipitation has long been used in protein purification. Recently, we reported a new cell culture clarification method for immunoglobulin G (IgG) purification, employing an advance elimination of chromatin heteroaggregates with a hybrid OA-solid phase system. This treatment reduced DNA more than 3 logs, histone below the detection limit (LOD), and non-histone host cell proteins (nh-HCP) by 90 % while conserving more than 90 % of the IgG monomer. In this study, we further investigated the conservation of IgG monomer and antibody light chain (LC) to the addition of OA/OA-solid phase complex, with or without histone and DNA in different combinations. The results showed that highly basic histone protein was the prime target in OA/OA-solid phase precipitation system for IgG purification, and the selective conservation of IgG monomer in this system was histone dependent. Our findings partially support the idea that OA works by sticking to electropositive hydrophobic domains on proteins, reducing their solubility, and causing them to agglomerate into large particles that precipitate from solution. Our findings also provide a new perspective for IgG purification and emphasize the necessity to re-examine the roles of various host contaminants in IgG purification.

  14. Rotenone and oxalic acid as alternative acaricidal treatments for Varroa destructor in honeybee colonies.

    PubMed

    Gregorc, Ales; Poklukar, Janez

    2003-02-27

    This experiment assessed the efficacy of rotenone and oxalic acid (OA) in an aqueous sugar solution in controlling the honeybee mite Varroa destructor. Colonies were populated with mite-infested brood combs and worker bees. Three rotenone or OA treatments administered during the period with capped brood on 31 July, 14 and 18 August resulted in an average efficacy of 24.10%. In untreated colonies mite mortality averaged 5.40%. No significant differences (P>0.05) were found between the rotenone and OA treatments. Three OA treatments administered on 9, 12 and 18 September resulted in a 77.93% mite mortality. An increase in mite drop (P<0.05) was observed at 2 and 4 days after each treatment. OA applications in broodless colonies resulted in significantly (P<0.001) higher mite mortality rates (98.65% average) than the three treatments of rotenone or OA in colonies with capped brood. The dynamics of mite mortality after each rotenone or OA treatment are discussed in this study.

  15. Nitrooleic acid, an endogenous product of nitrative stress, activates nociceptive sensory nerves via the direct activation of TRPA1.

    PubMed

    Taylor-Clark, Thomas E; Ghatta, Srinivas; Bettner, Weston; Undem, Bradley J

    2009-04-01

    Transient Receptor Potential A1 (TRPA1) is a nonselective cation channel, preferentially expressed on a subset of nociceptive sensory neurons, that is activated by a variety of reactive irritants via the covalent modification of cysteine residues. Excessive nitric oxide during inflammation (nitrative stress), leads to the nitration of phospholipids, resulting in the formation of highly reactive cysteine modifying agents, such as nitrooleic acid (9-OA-NO(2)). Using calcium imaging and electrophysiology, we have shown that 9-OA-NO(2) activates human TRPA1 channels (EC(50), 1 microM), whereas oleic acid had no effect on TRPA1. 9-OA-NO(2) failed to activate TRPA1 in which the cysteines at positions 619, 639, and 663 and the lysine at 708 had been mutated. TRPA1 activation by 9-OA-NO(2) was not inhibited by the NO scavenger carboxy-PTIO. 9-OA-NO(2) had no effect on another nociceptive-specific ion channel, TRPV1. 9-OA-NO(2) activated a subset of mouse vagal and trigeminal sensory neurons, which also responded to the TRPA1 agonist allyl isothiocyanate and the TRPV1 agonist capsaicin. 9-OA-NO(2) failed to activate neurons derived from TRPA1(-/-) mice. The action of 9-OA-NO(2) at nociceptive nerve terminals was investigated using an ex vivo extracellular recording preparation of individual bronchopulmonary C fibers in the mouse. 9-OA-NO(2) evoked robust action potential discharge from capsaicin-sensitive fibers with slow conduction velocities (0.4-0.7 m/s), which was inhibited by the TRPA1 antagonist AP-18. These data demonstrate that nitrooleic acid, a product of nitrative stress, can induce substantial nociceptive nerve activation through the selective and direct activation of TRPA1 channels.

  16. Protein-dependent Membrane Interaction of A Partially Disordered Protein Complex with Oleic Acid: Implications for Cancer Lipidomics

    PubMed Central

    Chaudhuri, Arunima; Prasanna, Xavier; Agiru, Priyanka; Chakraborty, Hirak; Rydström, Anna; Ho, James C. S.; Svanborg, Catharina; Sengupta, Durba; Chattopadhyay, Amitabha

    2016-01-01

    Bovine α-lactalbumin (BLA) forms cytotoxic complexes with oleic acid (OA) that perturbs tumor cell membranes, but molecular determinants of these membrane-interactions remain poorly understood. Here, we aim to obtain molecular insights into the interaction of BLA/BLA-OA complex with model membranes. We characterized the folding state of BLA-OA complex using tryptophan fluorescence and resolved residue-specific interactions of BLA with OA using molecular dynamics simulation. We integrated membrane-binding data using a voltage-sensitive probe and molecular dynamics (MD) to demonstrate the preferential interaction of the BLA-OA complex with negatively charged membranes. We identified amino acid residues of BLA and BLA-OA complex as determinants of these membrane interactions using MD, functionally corroborated by uptake of the corresponding α-LA peptides across tumor cell membranes. The results suggest that the α-LA component of these cytotoxic complexes confers specificity for tumor cell membranes through protein interactions that are maintained even in the lipid complex, in the presence of OA. PMID:27731329

  17. Oleic acid increases mitochondrial reactive oxygen species production and decreases endothelial nitric oxide synthase activity in cultured endothelial cells.

    PubMed

    Gremmels, Hendrik; Bevers, Lonneke M; Fledderus, Joost O; Braam, Branko; van Zonneveld, Anton Jan; Verhaar, Marianne C; Joles, Jaap A

    2015-03-15

    Elevated plasma levels of free fatty acids (FFA) are associated with increased cardiovascular risk. This may be related to FFA-induced elevation of oxidative stress in endothelial cells. We hypothesized that, in addition to mitochondrial production of reactive oxygen species, endothelial nitric oxide synthase (eNOS)-mediated reactive oxygen species production contributes to oleic acid (OA)-induced oxidative stress in endothelial cells, due to eNOS uncoupling. We measured reactive oxygen species production and eNOS activity in cultured endothelial cells (bEnd.3) in the presence of OA bound to bovine serum albumin, using the CM-H2DCFDA assay and the L-arginine/citrulline conversion assay, respectively. OA induced a concentration-dependent increase in reactive oxygen species production, which was inhibited by the mitochondrial complex II inhibitor thenoyltrifluoroacetone (TTFA). OA had little effect on eNOS activity when stimulated by a calcium-ionophore, but decreased both basal and insulin-induced eNOS activity, which was restored by TTFA. Pretreatment of bEnd.3 cells with tetrahydrobiopterin (BH4) prevented OA-induced reactive oxygen species production and restored inhibition of eNOS activity by OA. Elevation of OA levels leads to both impairment in receptor-mediated stimulation of eNOS and to production of mitochondrial-derived reactive oxygen species and hence endothelial dysfunction.

  18. Protein-dependent Membrane Interaction of A Partially Disordered Protein Complex with Oleic Acid: Implications for Cancer Lipidomics

    NASA Astrophysics Data System (ADS)

    Chaudhuri, Arunima; Prasanna, Xavier; Agiru, Priyanka; Chakraborty, Hirak; Rydström, Anna; Ho, James C. S.; Svanborg, Catharina; Sengupta, Durba; Chattopadhyay, Amitabha

    2016-10-01

    Bovine α-lactalbumin (BLA) forms cytotoxic complexes with oleic acid (OA) that perturbs tumor cell membranes, but molecular determinants of these membrane-interactions remain poorly understood. Here, we aim to obtain molecular insights into the interaction of BLA/BLA-OA complex with model membranes. We characterized the folding state of BLA-OA complex using tryptophan fluorescence and resolved residue-specific interactions of BLA with OA using molecular dynamics simulation. We integrated membrane-binding data using a voltage-sensitive probe and molecular dynamics (MD) to demonstrate the preferential interaction of the BLA-OA complex with negatively charged membranes. We identified amino acid residues of BLA and BLA-OA complex as determinants of these membrane interactions using MD, functionally corroborated by uptake of the corresponding α-LA peptides across tumor cell membranes. The results suggest that the α-LA component of these cytotoxic complexes confers specificity for tumor cell membranes through protein interactions that are maintained even in the lipid complex, in the presence of OA.

  19. [Polymorphism in the human 2'-5'-oligoadenylate synthetase genes (OAS), associated with predisposition to severe forms of tick-borne encephalitis, in populations from North Eurasia].

    PubMed

    Barkhash, A V; Babenko, V N; Kobzev, V F; Romashchenko, A G; Voevoda, M I

    2010-01-01

    2'-5'-oligoadenylate synthetases are a family of interferon-induced enzymes which play an important role in the antiviral defense in mammals. In human genome three genes encoding functional synthetases (OAS1, OAS2 and OAS3) form a cluster. Previously we found that particular genotypes and/or alleles of five single nucleotide polymorphisms (SNPs) located within OAS2 and OAS3 genes are associated with predisposition to severe forms of tick-borne encephalitis (TBE) in Russian population. In current study we investigated the distribution of three of that SNPs (OAS3rs2285932 (C/T Ile438Ile), OAS3rs2072136 (G/A, Ser567Ser) and OAS2 rs15895 (G/A, Trp720Ter relative to p71 isoform)) in seven populations from North Eurasia: Caucasians (Russians and Germans (from Altai region)), Central Asian Mongoloids (Altaians, Khakasses, Tuvinians and Shorians) and Arctic Mongoloids (Chukchi). Differences between populations in genotype, allele and haplotype frequencies and in linkage disequilibrium structure for these SNPs were detected. We found that these frequencies correlate with the ethnicity of the populations and with their supposed differential exposure to TBE virus. Particularly, the lowest frequencies of G/G genotype for OAS3 gene rs2072136 SNP (that according to our previously obtained data is associated with predisposition to severe forms of TBE) were found in Altaians, Khakasses, Tuvinians and Shorians who may highly contact with TBE virus in places of their habitation. Thus, data obtained allow to suppose that TBE virus might act as a selection factor for particular OAS genes variants in Central Asian Mongoloids.

  20. Crystal structure and physicochemical characterization of 3β-hydroxyolea-12-en-28-oic acid-3,5,6-trimethylpyrazin-2-methyl ester

    NASA Astrophysics Data System (ADS)

    Fu, Jing; Dong, Xiaoxv; Yin, Xinbing; Cao, Sali; Yang, Chunjing; He, Huyiligeqi; Ni, Jian

    2017-02-01

    3β-hydroxyolea-12-en-28-oic acid-3,5,6-trimethylpyrazin-2-methyl ester (T-OA) is a newly discovered potential antitumor compound. However, the poor solubility of T-OA leads to poor dissolution and limited clinical application. So as to enhance the dissolution and bioavailability of T-OA, an investigation of the polymorphism of T-OA was successfully undertaken. A new solvate and an amorphous form of T-OA were discovered through a comprehensive polymorph screening experiments. Their structures were elucidated by single-crystal structure analysis and extensively characterized by PXRD, DSC and SEM. The powder dissolution rates were compared with those of the previously known polymorph. Thermodynamic stability and phase transformation are also discussed in detail.

  1. Free Fatty Acids Induce Autophagy and LOX-1 Upregulation in Cultured Aortic Vascular Smooth Muscle Cells.

    PubMed

    Cheng, Cheng-I; Lee, Yueh-Hong; Chen, Po-Han; Lin, Yu-Chun; Chou, Ming-Huei; Kao, Ying-Hsien

    2016-11-05

    Elevation of free fatty acids (FFAs) is known to affect microvascular function and contribute to obesity-associated insulin resistance, hypertension, and microangiopathy. Proliferative and synthetic vascular smooth muscle cells (VSMCs) increase intimal thickness and destabilize atheromatous plaques. This study aimed to investigate whether saturated palmitic acid (PA) and monounsaturated oleic acid (OA) modulate autophagy activity, cell proliferation, and vascular tissue remodeling in an aortic VSMC cell line. Exposure to PA and OA suppressed growth of VSMCs without apoptotic induction, but enhanced autophagy flux with elevation of Beclin-1, Atg5, and LC3I/II. Cotreatment with autophagy inhibitors potentiated the FFA-suppressed VSMC growth and showed differential actions of PA and OA in autophagy flux retardation. Both FFAs upregulated lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) but only OA increased LDL uptake by VSMCs. Mechanistically, FFAs induced hyperphosphorylation of Akt, ERK1/2, JNK1/2, and p38 MAPK. All pathways, except OA-activated PI3K/Akt cascade, were involved in the LOX-1 upregulation, whereas blockade of PI3K/Akt and MEK/ERK cascades ameliorated the FFA-induced growth suppression on VSMCs. Moreover, both FFAs exhibited tissue remodeling effect through increasing MMP-2 and MMP-9 expression and their gelatinolytic activities, whereas high-dose OA significantly suppressed collagen type I expression. Conversely, siRNA-mediated LOX-1 knockdown significantly attenuated the OA-induced tissue remodeling effects in VSMCs. In conclusion, OA and PA enhance autophagy flux, suppress aortic VSMC proliferation, and exhibit vascular remodeling effect, thereby leading to the loss of VSMCs and interstitial ECM in vascular walls and eventually the instability of atheromatous plaques. J. Cell. Biochem. 9999: 1-13, 2016. © 2016 Wiley Periodicals, Inc.

  2. Antiurolithiatic Activity of Extract and Oleanolic Acid Isolated from the Roots of Lantana camara on Zinc Disc Implantation Induced Urolithiasis.

    PubMed

    Vyas, Narendra; Argal, Ameeta

    2013-01-01

    The present study was done to evaluate the antiurolithiatic activity of ethanolic extract of roots (ELC 200 mg/kg) and oleanolic acid (OA 60 mg/kg, O.A. 80 mg/kg, O.A. 100 mg/kg) isolated from roots of Lantana camara in albino wistar male rats using zinc disc implantation induced urolithiatic model. The group in which only zinc disc was implanted without any treatment showed increase in calcium output (23  ± 2.7 mg/dL). Cystone receiving animals showed significant protection from such change (P < 0.01). Treatment with OA and ELC significantly reduced the calcium output at a dose of OA 60 mg/kg (P < 0.01), OA 80 mg/kg (P < 0.01), ELC 200 mg/kg (P < 0.01), and OA 100 mg/kg (P < 0.001), as compared with zinc disc implanted group. The average weight of zinc discs along with the deposited crystals in the only disc implanted group was found to be 111 ± 8.6 mg. Group that received Cystone 500 mg/kg showed significant reduction in the depositions (P < 0.001). Similarly, the rats which received OA and ELC showed reduced formation of depositions around the zinc disc (P < 0.001). The X-ray images of rats also showed significant effect of OA and ELC on urolitiasis. Thus, OA and ELC showed promising antiurolithiatic activity in dose dependant manner.

  3. Lipophilic toxin profile in Galicia (Spain): 2005 toxic episode.

    PubMed

    Villar-González, A; Rodríguez-Velasco, M L; Ben-Gigirey, B; Botana, L M

    2007-06-15

    By the end of 2005, a toxic episode of phytoplankton origin in bivalve shellfish led to the closing down of several shellfish production areas in Galicia (northwestern region of Spain). During this time, different kinds of shellfish were collected and analysed by LC-MS/MS to search for the following lipophilic toxins: okadaic acid (OA), dinophysistoxins (DTXs), pectenotoxins (PTXs), azaspiracids (AZAs) and spirolides. Samples were analysed before alkaline hydrolysis in order to investigate the presence of free OA and DTXs, AZAs, PTXs and spirolides, and after alkaline hydrolysis to detect OA and DTXs esters. All of the samples were found to be contaminated with OA and/or DTX-2, as well as esterified forms of these diarrhetic shellfish poison (DSP) toxins, at levels around and above European regulatory limit (160 microg of okadaic acid equivalents/kg). The analyses of mussels and razor clam also revealed the presence of 13-desmethyl spirolide C (SPX-1) at levels below 31 microg/kg. Likewise, in many of the samples different levels of pectenotoxin-2 secoacid (PTX-2sa) were detected. DSP toxin esters represent practically the 100% of the total OA equivalents for scallops, clams, razor clams and cockles.

  4. Development of Certified Reference Materials for Diarrhetic Shellfish Poisoning Toxins, Part 2: Shellfish Matrix Materials.

    PubMed

    McCarron, Pearse; Reeves, Kelley L; Giddings, Sabrina D; Beach, Daniel G; Quilliam, Michael A

    2016-09-01

    Okadaic acid (OA) and its analogs, dinophysistoxins-1 (DTX1) and -2 (DTX2) are lipophilic biotoxins produced by marine algae that can accumulate in shellfish and cause the human illness known as diarrhetic shellfish poisoning (DSP). Regulatory testing of shellfish is required to protect consumers and the seafood industry. Certified reference materials (CRMs) are essential for the development, validation, and quality control of analytical methods, and thus play an important role in toxin monitoring. This paper summarizes work on research and development of shellfish tissue reference materials for OA and DTXs. Preliminary work established the appropriate conditions for production of shellfish tissue CRMs for OA and DTXs. Source materials, including naturally incurred shellfish tissue and cultured algae, were screened for their DSP toxins. This preliminary work informed planning and production of a wet mussel (Mytilus edulis) tissue homogenate matrix CRM. The homogeneity and stability of the CRM were evaluated and found to be fit-for-purpose. Extraction and LC-tandem MS methods were developed to accurately certify the concentrations of OA, DTX1, and DTX2 using a combination of standard addition and matrix-matched calibration to compensate for matrix effects in electrospray ionization. The concentration of domoic acid was also certified. Uncertainties were assigned following standards and guidelines from the International Organization for Standardization. The presence of other toxins in the CRM was also assessed and information values are reported for OA and DTX acyl esters.

  5. Assessment of okadaic acid effects on cytotoxicity, DNA damage and DNA repair in human cells.

    PubMed

    Valdiglesias, Vanessa; Méndez, Josefina; Pásaro, Eduardo; Cemeli, Eduardo; Anderson, Diana; Laffon, Blanca

    2010-07-07

    Okadaic acid (OA) is a phycotoxin produced by several types of dinoflagellates causing diarrheic shellfish poisoning (DSP) in humans. Symptoms induced by DSP toxins are mainly gastrointestinal, but the intoxication does not appear to be fatal. Despite this, this toxin presents a potential threat to human health even at concentrations too low to induce acute toxicity, since previous animal studies have shown that OA has very potent tumour promoting activity. However, its concrete action mechanism has not been described yet and the results reported with regard to OA cytotoxicity and genotoxicity are often contradictory. In the present study, the genotoxic and cytotoxic effects of OA on three different types of human cells (peripheral blood leukocytes, HepG2 hepatoma cells, and SHSY5Y neuroblastoma cells) were evaluated. Cells were treated with a range of OA concentrations in the presence and absence of S9 fraction, and MTT test and Comet assay were performed in order to evaluate cytotoxicity and genotoxicity, respectively. The possible effects of OA on DNA repair were also studied by means of the DNA repair competence assay, using bleomycin as DNA damage inductor. Treatment with OA in absence of S9 fraction induced not statistically significant decrease in cell viability and significant increase in DNA damage in all cell types at the highest concentrations investigated. However, only SHSY5Y cells showed OA induced genotoxic and cytotoxic effects in presence of S9 fraction. Furthermore, we found that OA can induce modulations in DNA repair processes when exposure was performed prior to BLM treatment, in co-exposure, or during the subsequent DNA repair process.

  6. Ursodeoxycholic Acid ameliorates pain severity and cartilage degeneration in monosodium iodoacetate-induced osteoarthritis in rats.

    PubMed

    Moon, Su-Jin; Jeong, Jeong-Hee; Jhun, Joo Yeon; Yang, Eun Ji; Min, Jun-Ki; Choi, Jong Young; Cho, Mi-La

    2014-02-01

    Osteoarthritis (OA) is a degenerative joint disease characterized by a progressive loss of cartilage. And, increased oxidative stress plays a relevant role in the pathogenesis of OA. Ursodeoxycholic acid (UDCA) is a used drug for liver diseases known for its free radical-scavenging property. The objectives of this study were to investigate the in vivo effects of UDCA on pain severity and cartilage degeneration using an experimental OA model and to explore its mode of actions. OA was induced in rats by intra-articular injection of monosodium iodoacetate (MIA) to the knee. Oral administration UDCA was initiated on the day of MIA injection. Limb nociception was assessed by measuring the paw withdrawal latency and threshold. Samples were analyzed macroscopically and histologically. Immunohistochemistry was used to investigate the expression of interleukin-1β (IL-1β), IL-6, nitrotyrosine and inducible nitric oxide synthase (iNOS) in knee joints. UDCA showed an antinociceptive property and attenuated cartilage degeneration. OA rats given oral UDCA significantly exhibited a decreased number of osteoclasts in subchondral bone legion compared with the vehicle-treated OA group. UDCA reduced the expression of IL-1β, IL-6, nitrotyrosine and iNOS in articular cartilage. UDCA treatment significantly attenuated the mRNA expression of matrix metalloproteinase-3 (MMP-3), -13, and ADAMTS5 in IL-1β-stimulated human OA chondrocytes. These results show the inhibitory effects of UDCA on pain production and cartilage degeneration in experimentally induced OA. The chondroprotective properties of UDCA were achieved by suppressing oxidative damage and inhibiting catabolic factors that are implicated in the pathogenesis of cartilage damage in OA.

  7. Orientatio ad Sidera (OAS): a comprehensive project for cultural astronomy research in ancient Mediterranean cultures

    NASA Astrophysics Data System (ADS)

    Belmonte, Juan Antonio; César González-García, A.; Rodríguez-Antón, Andrea

    2015-08-01

    During the last decade (starting in 2005), the OAS Project has been run, with the support of the Spanish research agencies. Within its framework, research on cultural astronomy has been developed for a series of ancient cultures from the Atlantic Islands to the Arabian Peninsula with the Meditterranean Sea as the pricipal axis of the project. A catalogue of studies has been performed in a set of cultures such as the Megalithic Phenomenon, ancient Egypt, Middle East Bronze and Iron Age civilizations and the Roman World, among many others. In this essay a general scope of the project and a series of most interesting outcomes will be presented. The evolutionary ties of the megalithic monuments of the Iberian Peninsula and elsewhere, the pattern of orientation of Egyptian temples and skyscaping practices within the Hittite, Commagenian or Nabataean cultures, among others, will be shown; finishing in a comprehensive, statistical and comparative study of the orientation patterns of thousands of ancient monuments of the Mediterranean region. Finally, a sketch of our most recent, still ongoing, research on the astronomical and non-astronomical practices used in the planning of cities in the Roman World will be a compelling and promising closing remark of our analysis.

  8. BOREAS TE-1 CH4 Flux Data Over The SSA-OA

    NASA Technical Reports Server (NTRS)

    Anderson, Darwin; Papagno, Andrea; Hall, Forrest G. (Editor); Newcomer, Jeffrey A. (Editor)

    2000-01-01

    The BOREAS TE-1 team collected various data to characterize the soil-plant systems in the BOREAS SSA. Particular emphasis was placed on nutrient biochemistry, the stores and transfers of organic carbon, and how the characteristics were related to measured methane fluxes. The overall transect in the Prince Albert National Park (Saskatchewan, Canada) included the major plant communities and related soils that occurred in that section of the boreal forest. Soil physical, chemical, and biological measurements along the transect were used to characterize the static environment, which allowed them to be related to methane fluxes. Chamber techniques were used to provide a measure of methane production/uptake. Chamber measurements coupled with flask sampling were used to determine the seasonality of methane fluxes. This particular data set contains methane flux and soil profile methane concentration values from the SSA-OA site. The data were collected from 29-May to 17-Sep-1994. The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  9. Fabrication of low-cost Mod-OA wood composite wind turbine blades

    NASA Technical Reports Server (NTRS)

    Lark, R. F.; Gougeon, M.; Thomas, G.; Zuteck, M.

    1983-01-01

    The wood composite blades were fabricated by using epoxy resin-bonded laminates of Douglas fir veneers for the leading edge spar sections and honeycomb-cored birch plywood panels for the blade trailing edge or afterbody sections. The blade was joined to the wind turbine hub assembly by epoxy resin-bonded steel load take-off studs. The wood composite blades were installed in the Mod-OA wind turbine test facility at Kahuku, Hawaii. The wood composite blades have successfully completed high power (average of 150 kW) operations for an eighteen month period (nearly 8,000 hr) before replacement with another set of wood composite blades. The original set of blades was taken out of service because of the failure of the shank on one stud. An inspection of the blades at NASA-Lewis showed that the shank failure was caused by a high stress concentration at a corrosion pit on the shank fillet radius which resulted in fatigue stresses in excess of the endurance limit.

  10. ORMDL3 is an inducible lung epithelial gene regulating metalloproteases, chemokines, OAS, and ATF6.

    PubMed

    Miller, Marina; Tam, Arvin B; Cho, Jae Youn; Doherty, Taylor A; Pham, Alexa; Khorram, Naseem; Rosenthal, Peter; Mueller, James L; Hoffman, Hal M; Suzukawa, Maho; Niwa, Maho; Broide, David H

    2012-10-09

    Orosomucoid like 3 (ORMDL3) has been strongly linked with asthma in genetic association studies, but its function in asthma is unknown. We demonstrate that in mice ORMDL3 is an allergen and cytokine (IL-4 or IL-13) inducible endoplasmic reticulum (ER) gene expressed predominantly in airway epithelial cells. Allergen challenge induces a 127-fold increase in ORMDL3 mRNA in bronchial epithelium in WT mice, with lesser 15-fold increases in ORMDL-2 and no changes in ORMDL-1. Studies of STAT-6-deficient mice demonstrated that ORMDL3 mRNA induction highly depends on STAT-6. Transfection of ORMDL3 in human bronchial epithelial cells in vitro induced expression of metalloproteases (MMP-9, ADAM-8), CC chemokines (CCL-20), CXC chemokines (IL-8, CXCL-10, CXCL-11), oligoadenylate synthetases (OAS) genes, and selectively activated activating transcription factor 6 (ATF6), an unfolded protein response (UPR) pathway transcription factor. siRNA knockdown of ATF-6α in lung epithelial cells inhibited expression of SERCA2b, which has been implicated in airway remodeling in asthma. In addition, transfection of ORMDL3 in lung epithelial cells activated ATF6α and induced SERCA2b. These studies provide evidence of the inducible nature of ORMDL3 ER expression in particular in bronchial epithelial cells and suggest an ER UPR pathway through which ORMDL3 may be linked to asthma.

  11. [Effectiveness and safety of intra-articular use of hyaluronic acid (Suplasyn) in the treatment of knee osteoarthritis].

    PubMed

    Gadek, Artur; Miśkowiec, Krzysztof; Wordliczek, Jerzy; Liszka, Henryk

    2011-01-01

    Osteoarthritis (OA) is one of the leading causes of disability in the elderly. The changes in the lubricating properties of synovial fluid lead to significant pain and loss of function. Viscosupplemen-tation, in which hyaluronic acid (HA) is injected into the knee joint, has evolved into an important part of our current therapeutic regimen in addressing the patient with knee pain due to OA. Intra-articular HA or hylan have proven to be an effective, safe, and tolerable treatment for symptomatic knee OA. In an effort to limit cardiovascular, gastrointestinal, and renal safety concerns with COX-2 selective and nonselective NSAIDs and maximize HA efficacy, it is even proposed using HA earlier in the treatment paradigm for knee OA and also as part of a comprehensive treatment strategy. Our study reconfirmed effectiveness and safety of intra-articular use of hyaluronic acid (Suplasyn) in the treatment of knee osteoarthritis.

  12. Nitro-oleic acid downregulates lipoprotein-associated phospholipase A2 expression via the p42/p44 MAPK and NFκB pathways

    PubMed Central

    Wang, Gangqi; Ji, Yuan; Li, Zhuang; Han, Xiaolei; Guo, Nannan; Song, Qi; Quan, Longquan; Wang, Tiedong; Han, Wenyu; Pang, Daxin; Ouyang, Hongsheng; Tang, Xiaochun

    2014-01-01

    Nitro-oleic acid (OA-NO2), acting as anti-inflammatory signaling mediators, are involved in multiple signaling pathways. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is well known as a cardiovascular risk biomarker. Our results showed that OA-NO2 downregulated the expression of Lp-PLA2 in a time- and dose-dependent manner, whereas native OA had no such effect. Furthermore, OA-NO2 could repress Lp-PLA2 expression in the peripheral blood mononuclear cells of apo CIII-transgenic (apo CIII TG) pigs, which exhibited higher Lp-PLA2 expression and activity than did wild-type (WT) pigs. OA-NO2 inhibited Lp-PLA2 expression in macrophages, independent of nitric oxide formation and PPARγ-activation. However, OA-NO2 downregulates Lp-PLA2 by inhibiting the p42/p44 mitogen-activated protein kinase (MAPK) and the nuclear factor κB (NFκB) pathways. When used to mediate anti-inflammatory signaling, the regulation of inflammatory cytokines and SOD by OA-NO2 might be associated with the reduction of Lp-PLA2. These results suggested that OA-NO2 might exert a vascular-protective effect partially via Lp-PLA2 inhibition. PMID:24809325

  13. Nitro-oleic acid downregulates lipoprotein-associated phospholipase A2 expression via the p42/p44 MAPK and NFκB pathways.

    PubMed

    Wang, Gangqi; Ji, Yuan; Li, Zhuang; Han, Xiaolei; Guo, Nannan; Song, Qi; Quan, Longquan; Wang, Tiedong; Han, Wenyu; Pang, Daxin; Ouyang, Hongsheng; Tang, Xiaochun

    2014-05-09

    Nitro-oleic acid (OA-NO2), acting as anti-inflammatory signaling mediators, are involved in multiple signaling pathways. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is well known as a cardiovascular risk biomarker. Our results showed that OA-NO2 downregulated the expression of Lp-PLA2 in a time- and dose-dependent manner, whereas native OA had no such effect. Furthermore, OA-NO2 could repress Lp-PLA2 expression in the peripheral blood mononuclear cells of apo CIII-transgenic (apo CIII TG) pigs, which exhibited higher Lp-PLA2 expression and activity than did wild-type (WT) pigs. OA-NO2 inhibited Lp-PLA2 expression in macrophages, independent of nitric oxide formation and PPARγ-activation. However, OA-NO2 downregulates Lp-PLA2 by inhibiting the p42/p44 mitogen-activated protein kinase (MAPK) and the nuclear factor κB (NFκB) pathways. When used to mediate anti-inflammatory signaling, the regulation of inflammatory cytokines and SOD by OA-NO2 might be associated with the reduction of Lp-PLA2. These results suggested that OA-NO2 might exert a vascular-protective effect partially via Lp-PLA2 inhibition.

  14. The Activation Mechanism of 2'-5'-Oligoadenylate Synthetase Gives New Insights Into OAS/cGAS Triggers of Innate Immunity.

    PubMed

    Lohöfener, Jan; Steinke, Nicola; Kay-Fedorov, Penelope; Baruch, Petra; Nikulin, Alexey; Tishchenko, Svetlana; Manstein, Dietmar J; Fedorov, Roman

    2015-05-05

    2'-5'-Oligoadenylate synthetases (OASs) produce the second messenger 2'-5'-oligoadenylate, which activates RNase L to induce an intrinsic antiviral state. We report on the crystal structures of catalytic intermediates of OAS1 including the OAS1·dsRNA complex without substrates, with a donor substrate, and with both donor and acceptor substrates. Combined with kinetic studies of point mutants and the previously published structure of the apo form of OAS1, the new data suggest a sequential mechanism of OAS activation and show the individual roles of each component. They reveal a dsRNA-mediated push-pull effect responsible for large conformational changes in OAS1, the catalytic role of the active site Mg(2+), and the structural basis for the 2'-specificity of product formation. Our data reveal similarities and differences in the activation mechanisms of members of the OAS/cyclic GMP-AMP synthase family of innate immune sensors. In particular, they show how helix 3103-α5 blocks the synthesis of cyclic dinucleotides by OAS1.

  15. Electrostatic interactions play an essential role in the binding of oleic acid with α-lactalbumin in the HAMLET-like complex: a study using charge-specific chemical modifications.

    PubMed

    Xie, Yongjing; Min, Soyoung; Harte, Níal P; Kirk, Hannah; O'Brien, John E; Voorheis, H Paul; Svanborg, Catharina; Hun Mok, K

    2013-01-01

    Human α-lactalbumin made lethal to tumor cells (HAMLET) and its analogs are partially unfolded protein-oleic acid (OA) complexes that exhibit selective tumoricidal activity normally absent in the native protein itself. To understand the nature of the interaction between protein and OA moieties, charge-specific chemical modifications of lysine side chains involving citraconylation, acetylation, and guanidination were employed and the biophysical and biological properties were probed. Upon converting the original positively-charged lysine residues to negatively-charged citraconyl or neutral acetyl groups, the binding of OA to protein was eliminated, as were any cytotoxic activities towards osteosarcoma cells. Retention of the positive charges by converting lysine residues to homoarginine groups (guanidination); however, yielded unchanged binding of OA to protein and identical tumoricidal activity to that displayed by the wild-type α-lactalbumin-oleic acid complex. With the addition of OA, the wild-type and guanidinated α-lactalbumin proteins underwent substantial conformational changes, such as partial unfolding, loss of tertiary structure, but retention of secondary structure. In contrast, no significant conformational changes were observed in the citraconylated and acetylated α-lactalbumins, most likely because of the absence of OA binding. These results suggest that electrostatic interactions between the positively-charged basic groups on α-lactalbumin and the negatively-charged carboxylate groups on OA molecules play an essential role in the binding of OA to α-lactalbumin and that these interactions appear to be as important as hydrophobic interactions.

  16. Segmental pulmonary vascular resistances during oleic acid lung injury in rabbits.

    PubMed

    Maarek, J M; Grimbert, F

    1994-10-01

    We studied in isolated rabbit lungs the effects of oleic acid (OA) injury on the segmental distribution of vascular resistance. Vascular occlusion pressures were measured in control and OA-injured preparations over 90 min. Capillary filtration coefficient KF,C increased from 0.61 (+/- 0.10) to 0.91 (+/- 0.14) g.min-1.mmHg-1.(100 g)-1 in OA-injured lungs whereas it remained constant in control lungs. Total pulmonary vascular resistance changed little in both control and OA-injured lungs. OA injury resulted in a 15% increase of the double occlusion capillary pressure. In addition, the contribution of the microvascular to the total vascular resistance rose from 8% to 22%. The increase in microvascular resistance was significant 15 min after OA on the arteriolar side and became significant 30 min later on the venular side. Oleic acid injury does not change the total pulmonary vascular resistance but alters the distribution of segmental resistances in the isolated rabbit lung, thereby contributing to the accumulation of lung water in this model of low pressure permeability edema.

  17. Protective effect of oleanolic acid on oxidized-low density lipoprotein induced endothelial cell apoptosis.

    PubMed

    Cao, Jianhua; Li, Guanghui; Wang, Meizhi; Li, Hui; Han, Zhiwu

    2015-10-01

    Oleanolic acid (3β-hydroxyolean-12-en-28-oic acid, OA) is a naturally-occurring triterpenoid with various promising pharmacological properties. The present study was conducted to determine the protective effects of OA against oxidized low-density lipoprotein (ox-LDL) induced endothelial cell apoptosis and the possible underlying mechanisms. Our results showed that ox-LDL significantly decreased cell viability and induced apoptosis in human umbilical vein endothelial cells (HUVECs). OA in the co-treatment showed a protective effect against ox-LDL induced loss in cell viability and an increase in apoptosis, which was associated with the modulating effect of OA on ox-LDL induced hypoxia-inducible factor 1α(HIF-1α) expression. Moreover, our results showed that the modulating effect of OA against ox-LDL induced HIF-1α expression was obtained via inhibition of lipoprotein receptor 1 (LOX-1)/reactive oxygen species (ROS) signaling. Collectively, we suggested that the protective effect of OA against ox-LDL induced HUVEC apoptosis might, at least in part, be obtained via inhibition of the LOX-1/ROS/HIF-1α signaling pathway.

  18. Effects of oleic acid on the high threshold barium current in seabass Dicentrarchus labrax ventricular myocytes.

    PubMed

    Chatelier, A; Imbert, N; Infante, J L Zambonino; McKenzie, D J; Bois, P

    2006-10-01

    The present study employed a patch clamp technique in isolated seabass ventricular myocytes to investigate the hypothesis that oleic acid (OA), a mono-unsaturated fatty acid, can exert direct effects upon whole-cell barium currents. Acute application of free OA caused a dose-dependent depression of the whole-cell barium current that was evoked by a voltage step to 0 mV from a holding potential of -80 mV. The derived 50% inhibitory concentration (IC50) was 12.49+/-0.27 micromol l(-1). At a concentration of 30 micromol l(-1), OA significantly reduced the current density to about 45% of control values, but did not modify either the shape of the current-density voltage relationship or the apparent reversal potential. In addition, OA did not modify the voltage dependence of either steady state inactivation or activation curves. Taken together, these results indicate that physiological concentrations of free OA decrease the conductance of the L-type inward current, without altering its properties of selectivity and its voltage dependence. The inhibitory effect of OA upon the L-type calcium channel may translate, in vivo, into a protective effect against arrhythmias induced by Ca2+ overload.

  19. Preparation and antitumor evaluation of self-assembling oleanolic acid-loaded Pluronic P105/d-α-tocopheryl polyethylene glycol succinate mixed micelles for non-small-cell lung cancer treatment

    PubMed Central

    Wu, Hao; Zhong, Qingxiang; Zhong, Rongling; Huang, Houcai; Xia, Zhi; Ke, Zhongcheng; Zhang, Zhenhai; Song, Jie; Jia, Xiaobin

    2016-01-01

    Oleanolic acid (OA) is a triterpenoid found in various fruits and vegetables and used in traditional Chinese medicine. OA plays a crucial role in the treatment of several cancers, but poor water solubility, low permeability, and significant efflux have limited its widespread clinical use. Vitamin E-d-α-tocopheryl polyethylene glycol succinate (vitamin E-TPGS) and Pluronic P105 were used to improve the solubility and permeability and to decrease the efflux of OA. OA-loaded mixed micelles were prepared by ethanol thin-film hydration. The physicochemical properties of the micelles, including zeta potential, morphology, particle size, solubility, drug loading, and drug entrapment efficiency were characterized. OA release from micelles was slower than that from the free drug system. OA uptake by A549 non-small-cell lung cancer (NSCLC) cells was enhanced by the micelles. A tumor model was established by injecting A549 cells into nude mice. In vivo imaging showed that OA-micelles could accumulate in the tumors of nude mice. Additionally, smaller tumor size and increased expression of pro-apoptotic proteins were observed in OA-micelle-treated mice, indicating that OA-micelles are more effective than free OA in treating cancer. In vitro experiments were performed using two NSCLC cell lines (A549 and PC-9). Cytotoxicity evaluations showed that the half-maximal inhibitory concentrations of free OA and OA-micelles were 36.8±4.8 and 20.9±3.7 μM, respectively, in A549 cells and 82.7±7.8 and 56.7±4.7 μM, respectively, in PC-9 cells. Apoptosis assays revealed that the apoptotic rate of OA-micelle-treated A549 and PC-9 cells was higher than that of cells treated with the same concentration of free OA. Wound healing and transwell assays showed that migration and invasion were significantly suppressed in OA-micelle-treated cells. Immunofluorescence and Western blot analyses confirmed that the epithelial–mesenchymal transition was reversed in OA-micelle-treated cells. Mixed

  20. Preparation and antitumor evaluation of self-assembling oleanolic acid-loaded Pluronic P105/d-α-tocopheryl polyethylene glycol succinate mixed micelles for non-small-cell lung cancer treatment.

    PubMed

    Wu, Hao; Zhong, Qingxiang; Zhong, Rongling; Huang, Houcai; Xia, Zhi; Ke, Zhongcheng; Zhang, Zhenhai; Song, Jie; Jia, Xiaobin

    Oleanolic acid (OA) is a triterpenoid found in various fruits and vegetables and used in traditional Chinese medicine. OA plays a crucial role in the treatment of several cancers, but poor water solubility, low permeability, and significant efflux have limited its widespread clinical use. Vitamin E-d-α-tocopheryl polyethylene glycol succinate (vitamin E-TPGS) and Pluronic P105 were used to improve the solubility and permeability and to decrease the efflux of OA. OA-loaded mixed micelles were prepared by ethanol thin-film hydration. The physicochemical properties of the micelles, including zeta potential, morphology, particle size, solubility, drug loading, and drug entrapment efficiency were characterized. OA release from micelles was slower than that from the free drug system. OA uptake by A549 non-small-cell lung cancer (NSCLC) cells was enhanced by the micelles. A tumor model was established by injecting A549 cells into nude mice. In vivo imaging showed that OA-micelles could accumulate in the tumors of nude mice. Additionally, smaller tumor size and increased expression of pro-apoptotic proteins were observed in OA-micelle-treated mice, indicating that OA-micelles are more effective than free OA in treating cancer. In vitro experiments were performed using two NSCLC cell lines (A549 and PC-9). Cytotoxicity evaluations showed that the half-maximal inhibitory concentrations of free OA and OA-micelles were 36.8±4.8 and 20.9±3.7 μM, respectively, in A549 cells and 82.7±7.8 and 56.7±4.7 μM, respectively, in PC-9 cells. Apoptosis assays revealed that the apoptotic rate of OA-micelle-treated A549 and PC-9 cells was higher than that of cells treated with the same concentration of free OA. Wound healing and transwell assays showed that migration and invasion were significantly suppressed in OA-micelle-treated cells. Immunofluorescence and Western blot analyses confirmed that the epithelial-mesenchymal transition was reversed in OA-micelle-treated cells. Mixed

  1. Evidence of okadaic acid production in a cultured strain of the marine dinoflagellate Prorocentrum rhathymum from Malaysia.

    PubMed

    Caillaud, A; de la Iglesia, P; Campàs, M; Elandaloussi, L; Fernández, M; Mohammad-Noor, N; Andree, K; Diogène, J

    2010-01-01

    Protein phosphatase inhibition assay (PPIA), Neuroblastoma cell-based assay (Neuro-2a CBA) and LC-MS/MS analysis revealed for the first time the production of okadaic acid (OA) by a Prorocentrum rhathymum strain. Low amounts of OA were detected by LC-MS/MS analysis. Inhibition of PP2A activity and a weak toxicity to the Neuro-2a CBA were also observed.

  2. Designer laying hen diets to improve egg fatty acid profile and maintain sensory quality

    PubMed Central

    Goldberg, Erin M; Ryland, Donna; Gibson, Robert A; Aliani, Michel; House, James D

    2013-01-01

    The fatty acid composition of eggs is highly reflective of the diet of the laying hen; therefore, nutritionally important fatty acids can be increased in eggs in order to benefit human health. To explore the factors affecting the hen's metabolism and deposition of fatty acids of interest, the current research was divided into two studies. In Study 1, the fatty acid profile of eggs from Bovan White hens fed either 8%, 14%, 20%, or 28% of the omega-6 fatty acid, linoleic acid (LA) (expressed as a percentage of total fatty acids), and an additional treatment of 14% LA containing double the amount of saturated fat (SFA) was determined. Omega-6 fatty acids and docosapentaenoic acid (DPA) in the yolk were significantly (P < 0.05) increased, and oleic acid (OA) and eicosapentaenoic acid (EPA) were significantly decreased with an increasing dietary LA content. In Study 2, the fatty acid and sensory profiles were determined in eggs from Shaver White hens fed either (1) 15% or 30% of the omega-3 fatty acid, alpha-linolenic acid (ALA) (of total fatty acids), and (2) low (0.5), medium (1), or high (2) ratios of SFA: LA+OA. Increasing this ratio resulted in marked increases in lauric acid, ALA, EPA, DPA, and docosahexaenoic acid (DHA), with decreases in LA and arachidonic acid. Increasing the dietary ALA content from 15% to 30% (of total fatty acids) did not overcome the DHA plateau observed in the yolk. No significant differences (P ≥ 0.05) in aroma or flavor between cooked eggs from the different dietary treatments were observed among trained panelists (n = 8). The results showed that increasing the ratio of SFA: LA+OA in layer diets has a more favorable effect on the yolk fatty acid profile compared to altering the LA content at the expense of OA, all while maintaining sensory quality. PMID:24804037

  3. Designer laying hen diets to improve egg fatty acid profile and maintain sensory quality.

    PubMed

    Goldberg, Erin M; Ryland, Donna; Gibson, Robert A; Aliani, Michel; House, James D

    2013-07-01

    The fatty acid composition of eggs is highly reflective of the diet of the laying hen; therefore, nutritionally important fatty acids can be increased in eggs in order to benefit human health. To explore the factors affecting the hen's metabolism and deposition of fatty acids of interest, the current research was divided into two studies. In Study 1, the fatty acid profile of eggs from Bovan White hens fed either 8%, 14%, 20%, or 28% of the omega-6 fatty acid, linoleic acid (LA) (expressed as a percentage of total fatty acids), and an additional treatment of 14% LA containing double the amount of saturated fat (SFA) was determined. Omega-6 fatty acids and docosapentaenoic acid (DPA) in the yolk were significantly (P < 0.05) increased, and oleic acid (OA) and eicosapentaenoic acid (EPA) were significantly decreased with an increasing dietary LA content. In Study 2, the fatty acid and sensory profiles were determined in eggs from Shaver White hens fed either (1) 15% or 30% of the omega-3 fatty acid, alpha-linolenic acid (ALA) (of total fatty acids), and (2) low (0.5), medium (1), or high (2) ratios of SFA: LA+OA. Increasing this ratio resulted in marked increases in lauric acid, ALA, EPA, DPA, and docosahexaenoic acid (DHA), with decreases in LA and arachidonic acid. Increasing the dietary ALA content from 15% to 30% (of total fatty acids) did not overcome the DHA plateau observed in the yolk. No significant differences (P ≥ 0.05) in aroma or flavor between cooked eggs from the different dietary treatments were observed among trained panelists (n = 8). The results showed that increasing the ratio of SFA: LA+OA in layer diets has a more favorable effect on the yolk fatty acid profile compared to altering the LA content at the expense of OA, all while maintaining sensory quality.

  4. Dissecting the contribution of knee joint NGF to spinal nociceptive sensitization in a model of OA pain in the rat

    PubMed Central

    Sagar, D.R.; Nwosu, L.; Walsh, D.A.; Chapman, V.

    2015-01-01

    Summary Objective Although analgesic approaches targeting nerve growth factor (NGF) for the treatment of osteoarthritis (OA) pain remain of clinical interest, neurophysiological mechanisms by which NGF contribute to OA pain remain unclear. We investigated the impact of local elevation of knee joint NGF on knee joint, vs remote (hindpaw), evoked responses of spinal neurones in a rodent model of OA pain. Design In vivo spinal electrophysiology was carried out in anaesthetised rats with established pain behaviour and joint pathology following intra-articular injection of monosodium iodoacetate (MIA), vs injection of saline. Neuronal responses to knee joint extension and flexion, mechanical punctate stimulation of the peripheral receptive fields over the knee and at a remote site (ipsilateral hind paw) were studied before, and following, intra-articular injection of NGF (10 μg/50 μl) or saline. Results MIA-injected rats exhibited significant local (knee joint) and remote (lowered hindpaw withdrawal thresholds) changes in pain behaviour, and joint pathology. Intra-articular injection of NGF significantly (P < 0.05) increased knee extension-evoked firing of spinal neurones and the size of the peripheral receptive fields of spinal neurones (100% increase) over the knee joint in MIA rats, compared to controls. Intra-articular NGF injection did not significantly alter responses of spinal neurones following noxious stimulation of the ipsilateral hind paw in MIA-injected rats. Conclusion The facilitatory effects of intra-articular injection of NGF on spinal neurones receiving input from the knee joint provide a mechanistic basis for NGF mediated augmentation of OA knee pain, however additional mechanisms may contribute to the spread of pain to remote sites. PMID:25623624

  5. The Emergence of Regional Organizations in Latin America and Implications for the Future of the Organization of American States (OAS)

    DTIC Science & Technology

    2012-04-10

    opportunities for cooperation between the two organizations. 9 In 2011, Insulza, at the Summit of Heads of State of MERCOSUR in Uruguay, also said...that MERCOSUR will play an increasing responsibility in the new advances of the international structure. 10 5 The OAS is a relevant institution...Southern Market ( MERCOSUR ) was created. In 1993, the US, Canada, and Mexico signed the North American Free Trade Agreement (NAFTA). 106 In 1996, an

  6. Management of osteoarthritis (OA) with the pharma-standard supplement FlexiQule (Boswellia): a 12-week registry.

    PubMed

    Belcaro, G; Dugall, M; Luzzi, R; Ledda, A; Pellegrini, L; Hu, S; Ippolito, E

    2015-10-22

    This registry study assessed the pharma-standard supplement FlexiQule (Boswellia extract in capsules) in the management of symptoms associated to osteoarthritis (OA) also managed with the 'standard management' (SM) in comparison with a group of patients managed only with SM. The 12- week registry included patients with symptomatic knee arthrosis. They were able to walk on a treadmill for a walking test and to complete the WOMAC questionnaire.

  7. Impact of OAS1 Exon 7 rs10774671 Genetic Variation on Liver Fibrosis Progression in Egyptian HCV Genotype 4 Patients.

    PubMed

    Bader El Din, Noha G; Anany, Mohamed A; Dawood, Reham M; Ibrahim, Marwa K; El-Shenawy, Reem; El Abd, Yasmin S; El Awady, Mostafa K

    2015-11-01

    The aim of this study was to assess the impact of genetic variants of oligoadenylate synthetase 1 (OAS1) single-nucleotide polymorphism (SNP) rs10774671 at the exon 7 splice acceptor site on liver fibrosis progression and hepatitis C virus (HCV) outcome in Egyptian HCV genotype 4 patients. In this study, 195 subjects were enrolled; 60 controls and 135 chronic HCV genotype 4 patients with different fibrosis grades. All subjects were genotyped for OAS1 SNP rs10774671 polymorphism by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. There was an increasing trend of liver fibrosis progression as 52.9% GG, 73.6% GA, and 83.3% AA genotypes were detected in late fibrosis patients (p = 0.025). The AA genotype was higher in the late fibrosis group than in the early fibrosis group (83.3% vs. 16.7%) (p = 0.001). The A allele was significantly affecting the liver fibrosis progression rate, more than the G allele (p = 0.001). The multivariate analysis showed that the OAS1 GA and AA genotypes were independent factors associated with liver progression (p = 0.009, odds ratio [OR] 3.467, 95% confidence interval [CI] 1.273-7.584). In addition, the A allele was associated with liver fibrosis progression (p = 0.014, OR 2.525, 95% CI 1.157-4.545). The polymorphism at OAS1 exon 7 rs3741981 might be a potential genetic marker and can be useful in the assessment of liver fibrosis progression and disease outcome in HCV-infected patients.

  8. Adverse Effects (AEs) of Topical NSAIDs in Older Adults with Osteoarthritis (OA): a Systematic Review of the Literature

    PubMed Central

    Makris, UE.; Kohler, MJ.; Fraenkel, L.

    2010-01-01

    Objective To systematically review the literature on reported adverse effects (AEs) associated with topical NSAID use in older adults with osteoarthritis (OA). Methods A systematic search of Medline (1950 to November 2009), Scopus, Embase, Web of Science, Cochrane databases, Dissertation and American College of Rheumatology Meeting Abstracts was performed to identify original randomized controlled trials, case reports, observational studies, editorials or dissertations reporting AEs from topical NSAIDs in older adults with OA. Information was sought on study and participant characteristics, detailed recording of application site and systemic AEs as well as withdrawals due to AEs. Results The initial search yielded 953 articles of which 19 met eligibility criteria. Subjects receiving topical NSAIDs reported up to 39.3% application site AEs, and up to 17.5% systemic AEs. Five cases of warfarin potentiation with topical agents were reported; 1 resulting in gastrointestinal bleeding. In formal trials, the withdrawal rate from AEs ranged from 0-21% in the topical agents, 0-25% in the oral NSAIDs, and 0-16% in the placebo group. Conclusion In summary, although topical NSAIDs are safer than oral NSAIDs (fewer severe gastrointestinal AEs), a substantial proportion of older adults report systemic AEs with topical agents. Moreover, the withdrawal rate due to AEs with topical agents is comparable to that of oral NSAIDs. Given the safety profile and withdrawal rates described in this study, further data are needed to determine the incremental benefits of topical NSAIDs compared to other treatment modalities in older adults with OA. PMID:20360183

  9. Overexpression of the Transcription Factor Sp1 Activates the OAS-RNAse L-RIG-I Pathway

    PubMed Central

    Dupuis-Maurin, Valéryane; Brinza, Lilia; Baguet, Joël; Plantamura, Emilie; Schicklin, Stéphane; Chambion, Solène; Macari, Claire; Tomkowiak, Martine; Deniaud, Emmanuelle; Leverrier, Yann

    2015-01-01

    Deregulated expression of oncogenes or transcription factors such as specificity protein 1 (Sp1) is observed in many human cancers and plays a role in tumor maintenance. Paradoxically in untransformed cells, Sp1 overexpression induces late apoptosis but the early intrinsic response is poorly characterized. In the present work, we studied increased Sp1 level consequences in untransformed cells and showed that it turns on an early innate immune transcriptome. Sp1 overexpression does not activate known cellular stress pathways such as DNA damage response or endoplasmic reticulum stress, but induces the activation of the OAS-RNase L pathway and the generation of small self-RNAs, leading to the upregulation of genes of the antiviral RIG-I pathway at the transcriptional and translational levels. Finally, Sp1-induced intrinsic innate immune response leads to the production of the chemokine CXCL4 and to the recruitment of inflammatory cells in vitro and in vivo. Altogether our results showed that increased Sp1 level in untransformed cells constitutes a novel danger signal sensed by the OAS-RNase L axis leading to the activation of the RIG-I pathway. These results suggested that the OAS-RNase L-RIG-I pathway may be activated in sterile condition in absence of pathogen. PMID:25738304

  10. Overexpression of the transcription factor Sp1 activates the OAS-RNAse L-RIG-I pathway.

    PubMed

    Dupuis-Maurin, Valéryane; Brinza, Lilia; Baguet, Joël; Plantamura, Emilie; Schicklin, Stéphane; Chambion, Solène; Macari, Claire; Tomkowiak, Martine; Deniaud, Emmanuelle; Leverrier, Yann; Marvel, Jacqueline; Michallet, Marie-Cécile

    2015-01-01

    Deregulated expression of oncogenes or transcription factors such as specificity protein 1 (Sp1) is observed in many human cancers and plays a role in tumor maintenance. Paradoxically in untransformed cells, Sp1 overexpression induces late apoptosis but the early intrinsic response is poorly characterized. In the present work, we studied increased Sp1 level consequences in untransformed cells and showed that it turns on an early innate immune transcriptome. Sp1 overexpression does not activate known cellular stress pathways such as DNA damage response or endoplasmic reticulum stress, but induces the activation of the OAS-RNase L pathway and the generation of small self-RNAs, leading to the upregulation of genes of the antiviral RIG-I pathway at the transcriptional and translational levels. Finally, Sp1-induced intrinsic innate immune response leads to the production of the chemokine CXCL4 and to the recruitment of inflammatory cells in vitro and in vivo. Altogether our results showed that increased Sp1 level in untransformed cells constitutes a novel danger signal sensed by the OAS-RNase L axis leading to the activation of the RIG-I pathway. These results suggested that the OAS-RNase L-RIG-I pathway may be activated in sterile condition in absence of pathogen.

  11. A novel compact mass detection platform for the open access (OA) environment in drug discovery and early development.

    PubMed

    Gao, Junling; Ceglia, Scott S; Jones, Michael D; Simeone, Jennifer; Antwerp, John Van; Zhang, Li-Kang; Ross, Charles W; Helmy, Roy

    2016-04-15

    A new 'compact mass detector' co-developed with an instrument manufacturer (Waters Corporation) as an interface for liquid chromatography (LC), specifically Ultra-high performance LC(®) (UPLC(®) or UHPLC) analysis was evaluated as a potential new Open Access (OA) LC-MS platform in the Drug Discovery and Early Development space. This new compact mass detector based platform was envisioned to provide increased reliability and speed while exhibiting significant cost, noise, and footprint reductions. The new detector was evaluated in batch mode (typically 1-3 samples per run) to monitor reactions and check purity, as well as in High Throughput Screening (HTS) mode to run 24, 48, and 96 well plates. The latter workflows focused on screening catalysis conditions, process optimization, and library work. The objective of this investigation was to assess the performance, reliability, and flexibility of the compact mass detector in the OA setting for a variety of applications. The compact mass detector results were compared to those obtained by current OA LC-MS systems, and the capabilities and benefits of the compact mass detector in the open access setting for chemists in the drug discovery and development space are demonstrated.

  12. Preharvest application of oxalic acid increased fruit size, bioactive compounds, and antioxidant capacity in sweet cherry cultivars (Prunus avium L.).

    PubMed

    Martínez-Esplá, Alejandra; Zapata, Pedro Javier; Valero, Daniel; García-Viguera, Cristina; Castillo, Salvador; Serrano, María

    2014-04-16

    Trees of 'Sweet Heart' and 'Sweet Late' sweet cherry cultivars (Prunus avium L.) were treated with oxalic acid (OA) at 0.5, 1.0, and 2.0 mM at 98, 112, and 126 days after full blossom. Results showed that all treatments increased fruit size at harvest, manifested by higher fruit volume and weight in cherries from treated trees than from controls, the higher effect being found with 2.0 mM OA (18 and 30% higher weight for 'Sweet Heart' and 'Sweet Late', respectively). Other quality parameters, such as color and firmness, were also increased by OA treatments, although no significant differences were found in total soluble solids or total acidity, showing that OA treatments did not affect the on-tree ripening process of sweet cherry. However, the increases in total anthocyanins, total phenolics, and antioxidant activity associated with the ripening process were higher in treated than in control cherries, leading to fruit with high bioactive compounds and antioxidant potential at commercial harvest (≅45% more anthocyanins and ≅20% more total phenolics). In addition, individual anthocyanins, flavonols, and chlorogenic acid derivatives were also increased by OA treatment. Thus, OA preharvest treatments could be an efficient and natural way to increase the quality and functional properties of sweet cherries.

  13. Oleic acid derivative of polyethylenimine-functionalized proliposomes for enhancing oral bioavailability of extract of Ginkgo biloba.

    PubMed

    Zheng, Bin; Yang, Shuang; Fan, Chunyu; Bi, Ye; Du, Lin; Zhao, Lingzhi; Lee, Robert J; Teng, Lesheng; Teng, Lirong; Xie, Jing

    2016-05-01

    The present systematic study focused to investigate the oleic acid derivative of branched polyethylenimine (bPEI-OA)-functionalized proliposomes for improving the oral delivery of extract of Ginkgo biloba (GbE). The GbE proliposomes were prepared by a spray drying method at varying ratios of egg yolk phosphatidylcholine and cholesterol, and the optimized formulation was tailored with bPEI-OA to obtain bPEI-OA-functionalized proliposomes. The formulations were characterized for particle size, zeta potential, and entrapment efficiency. The release of GbE from proliposomes exhibited a sustained release. And the release rate was regulated by changing the amount of bPEI-OA on the proliposomes. The physical state characterization studies showed some interactions between GbE and other materials, such as hydrogen bonds and van der Waals forces during the process of preparation of proliposomes. The in situ single-pass perfusion and oral bioavailability studies were performed in rats. The significant increase in absorption constant (Ka) and apparent permeability coefficient (Papp) from bPEI-OA-functionalized proliposomes indicated the importance of positive charge for effective uptake across the gastrointestinal tract. The oral bioavailability of bPEI-OA-functionalized proliposomes was remarkable enhanced in comparison with control and conventional proliposomes. The bPEI-OA-functionalized proliposomes showed great potential of improving oral absorption of GbE as a suitable carrier.

  14. Enhanced enzymatic hydrolysis and acetone-butanol-ethanol fermentation of sugarcane bagasse by combined diluted acid with oxidate ammonolysis pretreatment.

    PubMed

    Li, Hailong; Xiong, Lian; Chen, Xuefang; Wang, Can; Qi, Gaoxiang; Huang, Chao; Luo, Mutan; Chen, Xinde

    2017-03-01

    This study aims to propose a biorefinery pretreatment technology for the bioconversion of sugarcane bagasse (SB) into biofuels and N-fertilizers. Performance of diluted acid (DA), aqueous ammonia (AA), oxidate ammonolysis (OA) and the combined DA with AA or OA were compared in SB pretreatment by enzymatic hydrolysis, structural characterization and acetone-butanol-ethanol (ABE) fermentation. Results indicated that DA-OA pretreatment improves the digestibility of SB by sufficiently hydrolyzing hemicellulose into fermentable monosaccharides and oxidating lignin into soluble N-fertilizer with high nitrogen content (11.25%) and low C/N ratio (3.39). The enzymatic hydrolysates from DA-OA pretreated SB mainly composed of glucose was more suitable for the production of ABE solvents than the enzymatic hydrolysates from OA pretreated SB containing high ratio of xylose. The fermentation of enzymatic hydrolysates from DA-OA pretreated SB produced 12.12g/L ABE in 120h. These results suggested that SB could be utilized efficient, economic, and environmental by DA-OA pretreatment.

  15. Oxaloacetate acetylhydrolase gene mutants of Sclerotinia sclerotiorum do not accumulate oxalic acid, but do produce limited lesions on host plants.

    PubMed

    Liang, Xiaofei; Liberti, Daniele; Li, Moyi; Kim, Young-Tae; Hutchens, Andrew; Wilson, Ron; Rollins, Jeffrey A

    2015-08-01

    The oxaloacetate acetylhydrolase (OAH, EC 3.7.1.1)-encoding gene Ss-oah1 was cloned and functionally characterized from Sclerotinia sclerotiorum. Ss-oah1 transcript accumulation mirrored oxalic acid (OA) accumulation with neutral pH induction dependent on the pH-responsive transcriptional regulator Ss-Pac1. Unlike previously characterized ultraviolet (UV)-induced oxalate-deficient mutants ('A' mutants) which retain the capacity to accumulate OA, gene deletion Δss-oah1 mutants did not accumulate OA in culture or during plant infection. This defect in OA accumulation was fully restored on reintroduction of the wild-type (WT) Ss-oah1 gene. The Δss-oah1 mutants were also deficient in compound appressorium and sclerotium development and exhibited a severe radial growth defect on medium buffered at neutral pH. On a variety of plant hosts, the Δss-oah1 mutants established very restricted lesions in which the infectious hyphae gradually lost viability. Cytological comparisons of WT and Δss-oah1 infections revealed low and no OA accumulation, respectively, in subcuticular hyphae. Both WT and mutant hyphae exhibited a transient association with viable host epidermal cells at the infection front. In summary, our experimental data establish a critical requirement for OAH activity in S. sclerotiorum OA biogenesis and pathogenesis, but also suggest that factors independent of OA contribute to the establishment of primary lesions.

  16. Lack of association of a variable number of aspartic acid residues in the asporin gene with osteoarthritis susceptibility: case-control studies in Spanish Caucasians

    PubMed Central

    Rodriguez-Lopez, Julio; Pombo-Suarez, Manuel; Liz, Myriam; Gomez-Reino, Juan J; Gonzalez, Antonio

    2006-01-01

    A recent genetic association study has identified a microsatellite in the coding sequence of the asporin gene as a susceptibility factor for osteoarthritis (OA). Alleles of this microsatellite determine the variable number of aspartic acid residues in the amino-terminal end of the asporin protein. Asporin binds directly to the growth factor transforming growth factor beta and inhibits its anabolic effects in cartilage, which include stimulation of collagen and aggrecan synthesis. The OA-associated allele, with 14 aspartic acid residues, inhibits the anabolic effects of transforming growth factor beta more strongly than other asporin alleles, leading to increased OA liability. We have explored whether the association found in several cohorts of Japanese hip OA and knee OA patients was also present in Spanish Caucasians. We studied patients that had undergone total joint replacement for primary OA in the hip (n = 303) or the knee (n = 188) and patients with hand OA (n = 233), and we compared their results with controls (n = 294) lacking overt OA clinical symptoms. No significant differences were observed in any of the multiple comparisons performed, which included global tests of allele frequency distributions and specific comparisons as well as stratification by affected joint and by sex. Our results, together with reports from the United Kingdom and Greece, indicate that the stretch of aspartic acid residues in asporin is not an important factor in OA susceptibility among European Caucasians. It remains possible that lifestyle, environmental or genetic differences allow for an important effect of asporin variants in other ethnic groups as has been reported in the Japanese, but this should be supported by additional studies. PMID:16542493

  17. Evaluation of a commercially available organic acid product on body weight loss, carcass yield, and meat quality during preslaughter feed withdrawal in broiler chickens: A poultry welfare and economic perspective1

    PubMed Central

    Menconi, A.; Kuttappan, V. A.; Hernandez-Velasco, X.; Urbano, T.; Matté, F.; Layton, S.; Kallapura, G.; Latorre, J.; Morales, B. E.; Prado, O.; Vicente, J. L.; Barton, J.; Filho, R. L. Andreatti; Lovato, M.; Hargis, B. M.; Tellez, G.

    2014-01-01

    The effect of a commercial organic acid (OA) product on BW loss (BWL) during feed withdrawal and transportation, carcass yield, and meat quality was evaluated in broiler chickens. Two experiments were conducted in Brazil. Commercial houses were paired as control groups receiving regular water and treated groups receiving OA in the water. Treated birds had a reduction in BWL of 37 g in experiment 1 and 32.2 g in experiment 2. In experiment 2, no differences were observed in carcass yield between groups. Estimation of the cost benefit suggested a 1:16 ratio by using the OA. In experiment 3, conducted in Mexico, significant differences on water consumption, BWL, and meat quality characteristics were observed in chickens that were treated with the OA (P < 0.05). These data suggest this OA product may improve animal welfare and economic concerns in the poultry industry by reducing BWL and improving meat quality attributes. PMID:24570468

  18. Evaluation of a commercially available organic acid product on body weight loss, carcass yield, and meat quality during preslaughter feed withdrawal in broiler chickens: a poultry welfare and economic perspective.

    PubMed

    Menconi, A; Kuttappan, V A; Hernandez-Velasco, X; Urbano, T; Matté, F; Layton, S; Kallapura, G; Latorre, J; Morales, B E; Prado, O; Vicente, J L; Barton, J; Andreatti Filho, R L; Lovato, M; Hargis, B M; Tellez, G

    2014-02-01

    The effect of a commercial organic acid (OA) product on BW loss (BWL) during feed withdrawal and transportation, carcass yield, and meat quality was evaluated in broiler chickens. Two experiments were conducted in Brazil. Commercial houses were paired as control groups receiving regular water and treated groups receiving OA in the water. Treated birds had a reduction in BWL of 37 g in experiment 1 and 32.2 g in experiment 2. In experiment 2, no differences were observed in carcass yield between groups. Estimation of the cost benefit suggested a 1:16 ratio by using the OA. In experiment 3, conducted in Mexico, significant differences on water consumption, BWL, and meat quality characteristics were observed in chickens that were treated with the OA (P < 0.05). These data suggest this OA product may improve animal welfare and economic concerns in the poultry industry by reducing BWL and improving meat quality attributes.

  19. Nitro-oleic acid desensitizes TRPA1 and TRPV1 agonist responses in adult rat DRG neurons.

    PubMed

    Zhang, Xiulin; Koronowski, Kevin B; Li, Lu; Freeman, Bruce A; Woodcock, Stephen; de Groat, William C

    2014-01-01

    Nitro-oleic acid (OA-NO2), an electrophilic fatty acid nitroalkene byproduct of redox reactions, activates transient receptor potential ion channels (TRPA1 and TRPV1) in primary sensory neurons. To test the possibility that signaling actions of OA-NO2 might modulate TRP channels, we examined: (1) interactions between OA-NO2 and other agonists for TRPA1 (allyl-isothiocyanate, AITC) and TRPV1 (capsaicin) in rat dissociated dorsal root ganglion cells using Ca(2+) imaging and patch clamp techniques and (2) interactions between these agents on sensory nerves in the rat hindpaw. Ca(2+) imaging revealed that brief application (15-30 s) of each of the three agonists induced homologous desensitization. Heterologous desensitization also occurred when one agonist was applied prior to another agonist. OA-NO2 was more effective in desensitizing the response to AITC than the response to capsaicin. Prolonged exposure to OA-NO2 (20 min) had a similar desensitizing effect on AITC or capsaicin. Homologous and heterologous desensitizations were also demonstrated with patch clamp recording. Deltamethrin, a phosphatase inhibitor, reduced the capsaicin or AITC induced desensitization of OA-NO2 but did not suppress the OA-NO2 induced desensitization of AITC or capsaicin, indicating that heterologous desensitization induced by either capsaicin or AITC occurs by a different mechanism than the desensitization produced by OA-NO2. Subcutaneous injection of OA-NO2 (2.5mM, 35 μl) into a rat hindpaw induced delayed and prolonged nociceptive behavior. Homologous desensitization occurred with AITC and capsaicin when applied at 15 minute intervals, but did not occur with OA-NO2 when applied at a 30 min interval. Pretreatment with OA-NO2 reduced AITC-evoked nociceptive behaviors but did not alter capsaicin responses. These results raise the possibility that OA-NO2 might be useful clinically to reduce neurogenic inflammation and certain types of painful sensations by desensitizing TRPA1 expressing

  20. Oleanolic acid modulates the immune-inflammatory response in mice with experimental autoimmune myocarditis and protects from cardiac injury. Therapeutic implications for the human disease.

    PubMed

    Martín, R; Cordova, C; San Román, J A; Gutierrez, B; Cachofeiro, V; Nieto, M L

    2014-07-01

    Myocarditis and dilated cardiomyopathy (DCM) are inflammatory diseases of the myocardium, for which appropriate treatment remains a major clinical challenge. Oleanolic acid (OA), a natural triterpene widely distributed in food and medicinal plants, possesses a large range of biological effects with beneficial properties for health and disease prevention. Several experimental approaches have shown its cardioprotective actions, and OA has recently been proven effective for treating Th1 cell-mediated inflammatory diseases; however, its effect on inflammatory heart disorders, including myocarditis, has not yet been addressed. Therefore, the present study was undertaken to determine the effectiveness of OA in prevention and treatment of experimental autoimmune myocarditis (EAM). The utility of OA was evaluated in vivo through their administration to cardiac α-myosin (MyHc-α614-629)-immunized BALB/c mice from day 0 or day 21 post-immunization to the end of the experiment, and in vitro through their addition to stimulated-cardiac cells. Prophylactic and therapeutic administration of OA dramatically decreased disease severity: the heart weight/body weight ratio as well as plasma levels of brain natriuretic peptide and myosin-specific autoantibodies production were significantly reduced in OA-treated EAM animals, compared with untreated ones. Histological heart analysis showed that OA-treatment diminished cell infiltration, fibrosis and dystrophic calcifications. OA also decreased proliferation of cardiac fibroblast in vitro and attenuated calcium and collagen deposition induced by relevant cytokines of active myocarditis. Furthermore, in OA-treated EAM mice the number of Treg cells and the production of IL-10 and IL-35 were markedly increased, while proinflammatory and profibrotic cytokines were significantly reduced. We demonstrate that OA ameliorates both developing and established EAM by promoting an antiinflammatory cytokine profile and by interfering with the

  1. Hyaluronic acid in the management of osteoarthritis: injection therapies innovations

    PubMed Central

    Santilli, Valter; Paoloni, Marco; Mangone, Massimiliano; Alviti, Federica; Bernetti, Andrea

    2016-01-01

    Summary Osteoarthritis (OA) is a chronic degenerative joint disease characterized by pain and progressive functional limitation. Viscosupplementation with intra-articular (IA) hyaluronic acid (HA) could be a treatment option in OA, however recommendations made in different international guidelines for the non-surgical management of OA are not always concordant with regard to the role of IA injection therapies. Results from a recent Italian Consensus Conference underline how IA-HA to treat OA represents a widely used therapy in Italy. Specifically high molecular weight HA, cross-linked HA, and mobile reticulum HA are considered very useful to treat the OA joints from a great number of expert in Italy. These kinds of HA could reduce the NSAIDs intake, furthermore high-molecular weight and mobile reticulum HA are considered to be able to delay or avoid a joint prosthetic implant. This mini review highlights the results obtained from the Italian Consensus Conference “Appropriateness of clinical and organizational criteria for intra-articular injection therapies in osteoarthritis” and give further indication about innovation in IA-HA therapies. PMID:27920810

  2. A wogonin-rich-fraction of Scutellaria baicalensis root extract exerts chondroprotective effects by suppressing IL-1β-induced activation of AP-1 in human OA chondrocytes

    PubMed Central

    Khan, Nazir M.; Haseeb, Abdul; Ansari, Mohammad Y.; Haqqi, Tariq M.

    2017-01-01

    Osteoarthritis (OA) is a common joint disorder with varying degrees of inflammation and sustained oxidative stress. The root extract of Scutellaria baicalensis (SBE) has been used for the treatment of inflammatory and other diseases. Here, we performed activity-guided HPLC-fractionation of SBE, identified the active ingredient(s) and investigated its chondroprotective potential. We found that the Wogonin containing fraction-4 (F4) was the most potent fraction based on its ability to inhibit ROS production and the suppression of catabolic markers including IL-6, COX-2, iNOS, MMP-3, MMP-9, MMP-13 and ADAMTS-4 in IL-1β-treated OA chondrocytes. OA chondrocytes treated with F4 in the presence of IL-1β showed significantly enhanced expression of anabolic genes ACAN and COL2A1. In an in vitro model of cartilage degradation treatment with F4 inhibited s-GAG release from IL-1β-treated human cartilage explants. The inhibitory effect of F4 was not mediated through the inhibition of MAPKs and NF-κB activation but was mediated through the suppression of c-Fos/AP-1 activity at transcriptional and post transcriptional levels in OA chondrocytes. Purified Wogonin mimicked the effects of F4 in IL-1β-stimulated OA chondrocytes. Our data demonstrates that a Wogonin-rich fraction of SBE exert chondroprotective effects through the suppression of c-Fos/AP-1 expression and activity in OA chondrocytes under pathological conditions. PMID:28256567

  3. Tipping the balance: Sclerotinia sclerotiorum secreted oxalic acid suppresses host defenses by manipulating the host redox environment.

    PubMed

    Williams, Brett; Kabbage, Mehdi; Kim, Hyo-Jin; Britt, Robert; Dickman, Martin B

    2011-06-01

    Sclerotinia sclerotiorum is a necrotrophic ascomycete fungus with an extremely broad host range. This pathogen produces the non-specific phytotoxin and key pathogenicity factor, oxalic acid (OA). Our recent work indicated that this fungus and more specifically OA, can induce apoptotic-like programmed cell death (PCD) in plant hosts, this induction of PCD and disease requires generation of reactive oxygen species (ROS) in the host, a process triggered by fungal secreted OA. Conversely, during the initial stages of infection, OA also dampens the plant oxidative burst, an early host response generally associated with plant defense. This scenario presents a challenge regarding the mechanistic details of OA function; as OA both suppresses and induces host ROS during the compatible interaction. In the present study we generated transgenic plants expressing a redox-regulated GFP reporter. Results show that initially, Sclerotinia (via OA) generates a reducing environment in host cells that suppress host defense responses including the oxidative burst and callose deposition, akin to compatible biotrophic pathogens. Once infection is established however, this necrotroph induces the generation of plant ROS leading to PCD of host tissue, the result of which is of direct benefit to the pathogen. In contrast, a non-pathogenic OA-deficient mutant failed to alter host redox status. The mutant produced hypersensitive response-like features following host inoculation, including ROS induction, callose formation, restricted growth and cell death. These results indicate active recognition of the mutant and further point to suppression of defenses by the wild type necrotrophic fungus. Chemical reduction of host cells with dithiothreitol (DTT) or potassium oxalate (KOA) restored the ability of this mutant to cause disease. Thus, Sclerotinia uses a novel strategy involving regulation of host redox status to establish infection. These results address a long-standing issue involving the

  4. [Effectiveness and safety of intra-articular use of hyaluronic acid (Suplasyn I-Shot) in the treatment of knee osteoarthritis].

    PubMed

    Miśkowiec, Krzysztof; Gądek, Artur; Jurecka, Alicja; Sówka, Justyna; Ślusarski, Jakub; Liszka, Henryk; Wordliczek, Jerzy

    2016-01-01

    Osteoarthritis (OA) is one of the leading causes of disability in the elderly. The changes in the lubricating properties of synovial fluid lead to significant pain and loss of function. Viscosupplementation, in which hyaluronic acid (HA) is injected into the knee joint, has evolved into an important part of our current therapeutic regimen in addressing the patient with knee pain due to OA. Intra-articular HA has proven to be an effective, safe, and tolerable treatment for symptomatic knee OA. In an effort to limit cardiovascular, gastrointestinal and renal safety concerns with COX-2 selective and nonselective NSAIDs and maximize HA efficacy, it is even proposed using HA earlier in the treatment paradigm for knee OA and also as part of a comprehensive treatment strategy. Our study reconfirmed effectiveness and safety of intra-articular use of hyaluronic acid (Suplasyn) in the treatment of knee osteoarthritis.

  5. Effects of sulfur dioxide concentration on organic acids and β-carotene in dried apricots during storage.

    PubMed

    Salur-Can, Ayşenur; Türkyılmaz, Meltem; Özkan, Mehmet

    2017-04-15

    The effects of various sulfur dioxide (SO2) concentrations (0, 451, 832, 1594, 2112 and 3241mg/kg) on the profiles and contents of organic acids (OAs) and β-carotene in sulfured dried apricots (SDAs) were investigated during storage at 4, 20 and 30°C for 379days. In all samples, four OAs [malic acid (MA), citric acid (CA), succinic acid (SA) and oxalic acid (OXA)] were identified. SA (13.9-31.8g/kgdw) was the major OA in SDAs containing SO2 at lower than 1594mgSO2/kg, while MA (11.7-11.7g/kgdw) was the major OA in SDAs containing SO2 at higher than 1594mgSO2/kg. As SO2 concentration increased, CA and OXA contents increased whereas MA contents decreased. Moreover, the highest stabilities of β-carotene, MA and SO2 were determined in SDAs containing 1594mgSO2/kg at 4°C. Therefore, we suggest using 1594mgSO2/kg and storing SDAs at 4°C to protect OAs and β-carotene.

  6. Oleanolic acid suppresses aerobic glycolysis in cancer cells by switching pyruvate kinase type M isoforms.

    PubMed

    Liu, Jia; Wu, Ning; Ma, Leina; Liu, Ming; Liu, Ge; Zhang, Yuyan; Lin, Xiukun

    2014-01-01

    Warburg effect, one of the hallmarks for cancer cells, is characterized by metabolic switch from mitochondrial oxidative phosphorylation to aerobic glycolysis. In recent years, increased expression level of pyruvate kinase M2 (PKM2) has been found to be the culprit of enhanced aerobic glycolysis in cancer cells. However, there is no agent inhibiting aerobic glycolysis by targeting PKM2. In this study, we found that Oleanolic acid (OA) induced a switch from PKM2 to PKM1, and consistently, abrogated Warburg effect in cancer cells. Suppression of aerobic glycolysis by OA is mediated by PKM2/PKM1 switch. Furthermore, mTOR signaling was found to be inactivated in OA-treated cancer cells, and mTOR inhibition is required for the effect of OA on PKM2/PKM1 switch. Decreased expression of c-Myc-dependent hnRNPA1 and hnRNPA1 was responsible for OA-induced switch between PKM isoforms. Collectively, we identified that OA is an antitumor compound that suppresses aerobic glycolysis in cancer cells and there is potential that PKM2 may be developed as an important target in aerobic glycolysis pathway for developing novel anticancer agents.

  7. Effects of methylene blue in acute lung injury induced by oleic acid in rats

    PubMed Central

    Cassiano Silveira, Ana Paula; Vento, Daniella Alves; Albuquerque, Agnes Afrodite Sumarelli; Celotto, Andrea Carla; Tefé-Silva, Cristiane; Ramos, Simone Gusmão; Rubens de Nadai, Tales; Rodrigues, Alfredo José; Poli-Neto, Omero Benedicto

    2016-01-01

    Background In acute lung injury (ALI), rupture of the alveolar-capillary barrier determines the protein-rich fluid influx into alveolar spaces. Previous studies have reported that methylene blue (MB) attenuates such injuries. This investigation was carried out to study the MB effects in pulmonary capillary permeability. Methods Wistar rats were divided into five groups: (I) Sham: saline bolus; (II) MB, MB infusion for 2 h; (III) oleic acid (OA), OA bolus; (IV) MB/OA, MB infusion for 2 h, and at 5 min after from the beginning, concurrently with an OA bolus; and (V) OA/MB, OA bolus, and after 2 h, MB infusion for 2 h. After 4 h, blood, bronchoalveolar lavage (BAL), and lung tissue were collected from all groups for analysis of plasma and tissue nitric oxide, calculation of the wet weight to dry weight ratio (WW/DW), and histological examination of lung tissue. Statistical analysis was performed using nonparametric test. Results Although favourable trends have been observed for permeability improvement parameters (WW/WD and protein), the results were not statistically significant. However, histological analysis of lung tissue showed reduced lesion areas in both pre- and post-treatment groups. Conclusions The data collected using this experimental model was favourable only through macroscopic and histological analysis. These observations are valid for both MB infusions before or after induction of ALI. PMID:26855944

  8. Fermentation parameter optimization of microbial oxalic acid production from cashew apple juice.

    PubMed

    Betiku, Eriola; Emeko, Harrison A; Solomon, Bamidele O

    2016-02-01

    The potential of cashew apple juice (CAJ) as a carbon source for oxalic acid (OA) production via fermentation process was investigated in this study. The effects and interactions of CAJ concentration, time, pH, NaNO3 concentration and methanol concentration on OA production were determined in a central composite design (CCD) and the process was modelled and optimized using response surface methodology (RSM). The results showed that OA fermentation can be described significantly (p < 0.05) by a quadratic model giving regression coefficient (R (2)) of 0.9964. NaNO3 concentration was the most significant positive variable while methanol was not a significant variable. A maximum OA concentration of 122.68 g/l could be obtained using the optimum levels of CAJ of 150.0 g/l, pH of 5.4, time of 7.31 days, NaNO3 of 2 g/l and methanol of 1% volume. The production of OA was found to increase from 106.75 to 122.68 g/l using the statistically design optimization. This study revealed that CAJ could serve as an inexpensive and abundant feedstock for fermentative OA production, the resulting model could be used in the design of a typical pilot plant for a scale up production.

  9. Oleanolic Acid Suppresses Aerobic Glycolysis in Cancer Cells by Switching Pyruvate Kinase Type M Isoforms

    PubMed Central

    Ma, Leina; Liu, Ming; Liu, Ge; Zhang, Yuyan; Lin, Xiukun

    2014-01-01

    Warburg effect, one of the hallmarks for cancer cells, is characterized by metabolic switch from mitochondrial oxidative phosphorylation to aerobic glycolysis. In recent years, increased expression level of pyruvate kinase M2 (PKM2) has been found to be the culprit of enhanced aerobic glycolysis in cancer cells. However, there is no agent inhibiting aerobic glycolysis by targeting PKM2. In this study, we found that Oleanolic acid (OA) induced a switch from PKM2 to PKM1, and consistently, abrogated Warburg effect in cancer cells. Suppression of aerobic glycolysis by OA is mediated by PKM2/PKM1 switch. Furthermore, mTOR signaling was found to be inactivated in OA-treated cancer cells, and mTOR inhibition is required for the effect of OA on PKM2/PKM1 switch. Decreased expression of c-Myc-dependent hnRNPA1 and hnRNPA1 was responsible for OA-induced switch between PKM isoforms. Collectively, we identified that OA is an antitumor compound that suppresses aerobic glycolysis in cancer cells and there is potential that PKM2 may be developed as an important target in aerobic glycolysis pathway for developing novel anticancer agents. PMID:24626155

  10. Okadaic Acid Toxin at Sublethal Dose Produced Cell Proliferation in Gastric and Colon Epithelial Cell Lines

    PubMed Central

    del Campo, Miguel; Toledo, Héctor; Lagos, Néstor

    2013-01-01

    The aim of this study was to analyze the effect of Okadaic Acid (OA) on the proliferation of gastric and colon epithelial cells, the main target tissues of the toxin. We hypothesized that OA, at sublethal doses, activates multiple signaling pathways, such as Erk and Akt, through the inhibition of PP2A. To demonstrate this, we carried out curves of doses and time response against OA in AGS, MKN-45 and Caco 2 cell lines, and found an increase in the cell proliferation at sublethal doses, at 24 h or 48 h exposure. Indeed, cells can withstand high concentrations of the toxin at 4 h exposure, the time chosen considering the maximum time before total gastric emptying. We have proved that this increased proliferation is due to an overexpression of Cyclin B, a cyclin that promotes the passage from G2 to mitosis. In addition, we have demonstrated that OA induces activation of Akt and Erk in the three cells lines, showing that OA can activate pathways involved in oncogenesis. In conclusion, this study contributes to the knowledge about the possible effects of chronic OA consumption. PMID:24317467

  11. Enzyme-linked immunosensor based on super paramagnetic nanobeads for easy and rapid detection of okadaic acid.

    PubMed

    Hayat, Akhtar; Barthelmebs, Lise; Marty, Jean-Louis

    2011-04-01

    Okadaic acid (OA), a lipophilic phycotoxin highly toxic to humans is produced by toxigenic dinoflagellates. The need to develop high performing methods for OA analysis able to improve the traditional ones is evident. In this work, competitive indirect enzyme-linked electrochemical immunosensor based on super paramagnetic nanobeads has been developed for the detection of OA. Streptavidin-coated magnetic beads were used as support to immobilize the biotinylated OA. Preliminary, colorimetric tests were performed in order to optimize different experimental parameters. Electrochemical detection was carried out by differential pulse voltammetry (DPV). The limit of detection (LOD) (0.38 μg L(-1)), the mid point value (IC(50)) (3.15 μg L(-1)) and the time needed (60 min) for analysis of a real sample validated the developed electrochemical immunosensor as a promising tool for routine use. The matrix effect and the recovery rate were also assessed, showing an excellent percentage of recovery.

  12. Okadaic acid meet and greet: an insight into detection methods, response strategies and genotoxic effects in marine invertebrates.

    PubMed

    Prego-Faraldo, María Verónica; Valdiglesias, Vanessa; Méndez, Josefina; Eirín-López, José M

    2013-08-09

    Harmful Algal Blooms (HABs) constitute one of the most important sources of contamination in the oceans, producing high concentrations of potentially harmful biotoxins that are accumulated across the food chains. One such biotoxin, Okadaic Acid (OA), is produced by marine dinoflagellates and subsequently accumulated within the tissues of filtering marine organisms feeding on HABs, rapidly spreading to their predators in the food chain and eventually reaching human consumers causing Diarrhetic Shellfish Poisoning (DSP) syndrome. While numerous studies have thoroughly evaluated the effects of OA in mammals, the attention drawn to marine organisms in this regard has been scarce, even though they constitute primary targets for this biotoxin. With this in mind, the present work aimed to provide a timely and comprehensive insight into the current literature on the effect of OA in marine invertebrates, along with the strategies developed by these organisms to respond to its toxic effect together with the most important methods and techniques used for OA detection and evaluation.

  13. Stearic acid-induced cardiac lipotoxicity is independent of cellular lipid and is mitigated by the fatty acids oleic and capric acid but not by the PPAR agonist troglitazone.

    PubMed

    Rabkin, Simon W; Lodhia, Parth; Lodha, Parth

    2009-08-01

    The objective of this study was to examine the potential of stearic acid to induce cardiomyocyte cell death and the hypothesis that the amount of cellular lipid is a determinant of cell death. In cardiomyocytes from embryonic chick heart, stearic acid (SA) produced a significant (P < 0.001) concentration-dependent increase in cell death with an ED(50) of 71 microM. In contrast, capric (C10:0) or oleic acid (OA; C18:1), at < 200 microM, did not alter cell viability. Stearic acid-induced cell death was significantly reduced by OA and to a lesser extent by capric acid. Neither OA nor capric acid altered cell death produced by potassium cyanide and deoxyglucose. Stearic acid (100 microM) induced a significant (P < 0.05) twofold increase in cellular lipid as assessed by Nile blue and Sudan Black staining. A role for cellular lipid in cardiomyocyte death was excluded because OA increased cellular lipid, at concentrations that did not induce cell death; OA did not alter SA-induced cellular fat stores but reduced cell death; and the PPARgamma; agonist troglitazone at concentrations that reduced cellular lipid content did not alter cell death. High concentrations of troglitazone, however, induced cell death. In summary, SA is a potent inducer of cardiac cell death and intracellular lipid accumulation. The amount of intracellular lipid, however, is not a determinant of cardiomyocyte cell death. Troglitazone has potential cardiotoxicity at high doses but, at lower concentrations, does not prevent cardiac lipotoxicity, which can be completely prevented by low concentrations of oleic acid.

  14. GC-FID determination and pharmacokinetic studies of oleanolic acid in human serum.

    PubMed

    Rada, Mirela; Castellano, José María; Perona, Javier S; Guinda, Ángeles

    2015-11-01

    Analytical interest of OA determination in human serum has increased owing to the increasing interest in pharmaceutical research by pharmaceutical properties. A simple, specific, precise and accurate GC method with flame ionization detector (FID) developed and validated for the determination of oleanolic acid (OA) in human serum (HS). To an aliquot of HS, internal standard was added and a combination of liquid-liquid extraction with a mixture of diethyl ether-isopropyl alcohol, filtration and consecutive GC resulted in separation and quantification of OA. The organic phase was analyzed using a GC system equipped with a 30 × 0.25 mm i.d. Rtx-65TG capillary column and FID detection. Total chromatographic time was 10 min and no interfering peaks from endogenous components in blank serum were observed. The OA/internal standard peak area ratio was linearly fitted to the OA concentration (r = 0.992) over the range 10-1500 ng/mL. The mean serum extraction recovery of OA was 96.7 ± 1.0% and the lower limit of quantification based on 5 mL of serum was 10.7 ng/mL. The intra-day coefficient of variation ranged from 1.3 to 3.6% and inter-day varied from 1.4 to 4.5%. The developed method was used to study the pharmacokinetics of OA after oral administration in humans. The assay was simple, sensitive, precise and accurate for the use in the study of the mechanisms of absorption and distribution of OA in humans.

  15. Evaluation of 10-Nitro Oleic Acid Bio-Elimination in Rats and Humans

    PubMed Central

    Salvatore, Sonia R.; Vitturi, Dario A.; Fazzari, Marco; Jorkasky, Diane K.; Schopfer, Francisco J.

    2017-01-01

    Nitrated fatty acids are endogenously present in human and animal tissues, as well as in plant-derived oils. In particular, 10-nitro oleic acid (10-NO2-OA) potently induces Nrf2-dependent antioxidant gene expression and inhibits TLR4/NF-κB signaling, thus promoting an overall cyto-protective and anti-inflammatory response. 10-NO2-OA has been extensively tested in animal models and is currently undergoing clinical evaluation in humans. Bio-elimination pathways for 10-NO2-OA were evaluated in rats (30 mg/kg·day) and in humans (0.34 mg/kg) using samples obtained from a double-blind, dose-rising clinical trial. Quantitative radiochromatographic/MS analysis indicated that the renal and fecal pathways are the main routes for 10-NO2-OA excretion in rats, and allowed the identification of 4-nitro-octanedioic acid (NO2-8:0-diCOOH) as the most abundant metabolite in rat urine. In addition, high resolution LC-MS/MS analysis revealed the presence of a novel series of urinary metabolites including ω-carboxylation and β-oxidation products, as well as N-acetylcysteine, taurine and sulfo-conjugates in both rats and humans. Overall, the findings reported herein not only provide valuable tools for the experimental evaluation of 10-NO2-OA levels in vivo, but importantly they also set the basis for monitoring its metabolism during potential clinical interventions in humans. PMID:28054588

  16. Triterpenic Acids Present in Hawthorn Lower Plasma Cholesterol by Inhibiting Intestinal ACAT Activity in Hamsters.

    PubMed

    Lin, Yuguang; Vermeer, Mario A; Trautwein, Elke A

    2011-01-01

    Hawthorn (Crataegus pinnatifida) is an edible fruit used in traditional Chinese medicine to lower plasma lipids. This study explored lipid-lowering compounds and underlying mechanisms of action of hawthorn. Hawthorn powder extracts inhibited acylCoA:cholesterol acyltransferase (ACAT) activity in Caco-2 cells. The inhibitory activity was positively associated with triterpenic acid (i.e., oleanolic acid (OA) and ursolic acid (UA)) contents in the extracts. Cholesterol lowering effects of hawthorn and its potential additive effect in combination with plant sterol esters (PSE) were further studied in hamsters. Animals were fed a semi-synthetic diet containing 0.08% (w/w) cholesterol (control) or the same diet supplemented with (i) 0.37% hawthorn dichloromethane extract, (ii) 0.24% PSE, (iii) hawthorn dichloromethane extract (0.37%) plus PSE (0.24%) or (iv) OA/UA mixture (0.01%) for 4 weeks. Compared to the control diet, hawthorn, PSE, hawthorn plus PSE and OA/UA significantly lowered plasma non-HDL (VLDL + LDL) cholesterol concentrations by 8%, 9%, 21% and 6% and decreased hepatic cholesterol ester content by 9%, 23%, 46% and 22%, respectively. The cholesterol lowering effects of these ingredients were conversely associated with their capacities in increasing fecal neutral sterol excretion. In conclusion, OA and UA are responsible for the cholesterol lowering effect of hawthorn by inhibiting intestinal ACAT activity. In addition, hawthorn and particularly its bioactive compounds (OA and UA) enhanced the cholesterol lowering effect of plant sterols.

  17. Identification of olivetolic acid cyclase from Cannabis sativa reveals a unique catalytic route to plant polyketides.

    PubMed

    Gagne, Steve J; Stout, Jake M; Liu, Enwu; Boubakir, Zakia; Clark, Shawn M; Page, Jonathan E

    2012-07-31

    Δ(9)-Tetrahydrocannabinol (THC) and other cannabinoids are responsible for the psychoactive and medicinal properties of Cannabis sativa L. (marijuana). The first intermediate in the cannabinoid biosynthetic pathway is proposed to be olivetolic acid (OA), an alkylresorcinolic acid that forms the polyketide nucleus of the cannabinoids. OA has been postulated to be synthesized by a type III polyketide synthase (PKS) enzyme, but so far type III PKSs from cannabis have been shown to produce catalytic byproducts instead of OA. We analyzed the transcriptome of glandular trichomes from female cannabis flowers, which are the primary site of cannabinoid biosynthesis, and searched for polyketide cyclase-like enzymes that could assist in OA cyclization. Here, we show that a type III PKS (tetraketide synthase) from cannabis trichomes requires the presence of a polyketide cyclase enzyme, olivetolic acid cyclase (OAC), which catalyzes a C2-C7 intramolecular aldol condensation with carboxylate retention to form OA. OAC is a dimeric α+β barrel (DABB) protein that is structurally similar to polyketide cyclases from Streptomyces species. OAC transcript is present at high levels in glandular trichomes, an expression profile that parallels other cannabinoid pathway enzymes. Our identification of OAC both clarifies the cannabinoid pathway and demonstrates unexpected evolutionary parallels between polyketide biosynthesis in plants and bacteria. In addition, the widespread occurrence of DABB proteins in plants suggests that polyketide cyclases may play an overlooked role in generating plant chemical diversity.

  18. The nitrated fatty acid 10-nitro-oleate attenuates allergic airway disease.

    PubMed

    Reddy, Aravind T; Lakshmi, Sowmya P; Dornadula, Sireesh; Pinni, Sudheer; Rampa, Dileep R; Reddy, Raju C

    2013-09-01

    Asthma is a serious, growing problem worldwide. Inhaled steroids, the current standard therapy, are not always effective in this chronic inflammatory disease and can cause adverse effects. We tested the hypothesis that nitrated fatty acids (NFAs) may provide an effective alternative treatment. NFAs are endogenously produced by nonenzymatic reaction of NO with unsaturated fatty acids and exert anti-inflammatory actions both by activating the nuclear hormone receptor peroxisome proliferator-activated receptor (PPAR)γ and via PPAR-independent mechanisms, but whether they might ameliorate allergic airway disease was previously untested. We found that pulmonary delivery of the NFA 10-nitro-oleic acid (OA-NO2) reduced the severity of murine allergic airway disease, as assessed by various pathological and molecular markers. Fluticasone, an inhaled steroid commonly used to treat asthma, produced similar effects on most end points, but only OA-NO2 induced robust apoptosis of neutrophils and their phagocytosis by alveolar macrophages. This suggests that OA-NO2 may be particularly effective in neutrophil-rich, steroid-resistant severe asthma. In primary human bronchial epithelial cells, OA-NO2 blocked phosphorylation and degradation of IκB and enhanced inhibitory binding of PPARγ to NF-κB. Our results indicate that the NFA OA-NO2 is efficacious in preclinical models of allergic airway disease and may have potential for treating asthma patients.

  19. In vivo analgesic and anti-inflammatory activities of ursolic acid and oleanoic acid from Miconia albicans (Melastomataceae).

    PubMed

    Vasconcelos, Maria Anita L; Royo, Vanessa A; Ferreira, Daniele S; Crotti, Antonio E Miller; Andrade e Silva, Márcio L; Carvalho, José Carlos T; Bastos, Jairo Kenupp; Cunha, Wilson R

    2006-01-01

    The aim of this work was to use in vivo models to evaluate the analgesic and anti-inflammatory activities of ursolic acid (UA) and oleanoic acid (OA), the major compounds isolated as an isomeric mixture from the crude methylene chloride extract of Miconia albicans aerial parts in an attempt to clarify if these compounds are responsible for the analgesic properties displayed by this plant. Ursolic acid inhibited abdominal constriction in a dose-dependent manner, and the result obtained at a content of 40 mg kg(-1) was similar to that produced by administration of acetylsalicylic acid at a content of 100 mg kg(-1). Both acids reduced the number of paw licks in the second phase of the formalin test, and both of them displayed a significant anti-inflammatory effect at a content of 40 mg kg(-1). It is noteworthy that the administration of the isolated mixture, containing 65% ursolic acid/35% oleanolic acid, did not display significant analgesic and anti-inflammatory activities. On the basis of the obtained results, considering that the mixture of UA and OA was poorly active, it is suggested that other compounds, rather than UA and OA, should be responsible for the evaluated activities in the crude extract, since the crude extract samples displayed good activities.

  20. Aberrant splicing in the ocular albinism type 1 gene (OA1/GPR143) is corrected in vitro by morpholino antisense oligonucleotides.

    PubMed

    Vetrini, Francesco; Tammaro, Roberta; Bondanza, Sergio; Surace, Enrico M; Auricchio, Alberto; De Luca, Michele; Ballabio, Andrea; Marigo, Valeria

    2006-05-01

    An intronic point mutation was identified in the ocular albinism type 1 (OA1) gene (HUGO symbol, GPR143) in a family with the X-linked form of ocular albinism. Interestingly, the mutation creates a new acceptor splice site in intron 7 of the OA1 gene. In addition to low levels of normally spliced mRNA product of the OA1 gene, the patient samples contained also an aberrantly spliced mRNA with a 165 bp fragment of intron 7 (from position +750 to +914) inserted between exons 7 and 8. The abnormal transcript contained a premature stop codon and was unstable, as revealed by Northern blot analysis. We defined that mutation NC_000023.8:g.25288G>A generated a consensus binding motif for the splicing factor enhancer ASF/SF2, which most likely favored transcription of the aberrant mRNA. Furthermore, it activated a cryptic donor-splice site causing the inclusion between exons 7 and 8 of the 165 bp intronic fragment. Thus, the aberrant splicing is most likely explained by the generation of a de novo splicing enhancer motif. Finally, to rescue OA1 expression in the patient's melanocytes, we designed an antisense morpholino modified oligonucleotide complementary to the mutant sequence. The morpholino oligonucleotide (MO) was able to rescue OA1 expression and restore the OA1 protein level in the patient's melanocytes through skipping of the aberrant inclusion. The use of MO demonstrated that the lack of OA1 was caused by the generation of a new splice site. Furthermore, this technique will lead to new approaches to correct splice site mutations that cause human diseases.

  1. Delayed treatment with oleanolic acid attenuates tubulointerstitial fibrosis in chronic cyclosporine nephropathy through Nrf2/HO-1 signaling

    PubMed Central

    2014-01-01

    Background Nuclear factor erythroid-2-related factor-2 (Nrf2) is known to protect against tissue injury by orchestrating antioxidant and detoxification responses to oxidative stress. This study investigated whether upregulation of Nrf2-dependent signaling by oleanolic acid (OA), which is known to activate Nrf2, could attenuate renal inflammation and fibrosis in cyclosporine (CsA)-induced kidney injury. Methods Male ICR mice were divided into four treatment groups: Vehicle (VH, n = 6), VH + OA (n = 6), CsA (n = 8), and CsA + OA (n = 8). For the OA-treated groups, OA (25 mg/kg/day) was administered by intraperitoneal injection for the final week of the 4-week experimental period. Renal function, morphologies and signaling were evaluated at the end of the study. Results Treatment with CsA resulted in decreased kidney function and urine osmolality and increased urine volume and urinary albumin levels. The CsA-induced changes were improved by OA treatment. Specifically, administration of OA decreased tubulointerstitial fibrosis and inflammation scores that were increased in CsA-treated mice. Furthermore, OA treatment decreased urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) and 8-epi-prostaglandin F2α (8-iso-PGF2α) levels. The beneficial effects of OA were attributed to an increased ratio of nuclear/total Nrf2 and subsequently enhanced expression of heme oxygenase (HO)-1, as well as a stable level of Kelch-like ECH-associated protein 1 (Keap1) expression, indicating that OA enhanced nuclear translocation of Nrf2. Increased apoptotic cell death and a high ratio of B cell leukaemia/lymphoma 2 (Bcl-2)-associated X protein (Bax) to Bcl-2 in CsA-treated mice were also significantly ameliorated by OA treatment. Conclusion Our results suggest that OA activates Nrf2/HO-1 signaling in chronic CsA nephropathy, which may have beneficial effects on inflammation and oxidative stress. PMID:24559268

  2. Determination of residues of oxolinic acid and flumequine in freeze-dried salmon muscle and skin by HPLC with fluorescence detection.

    PubMed

    Pouliquen, H; Morvan, M L

    2002-03-01

    A procedure for the determination of residues of oxolinic acid (OA) and flumequine (FLU) in freeze-dried salmon muscle with attached skin, using reversed-phase high-performance liquid chromatography, is described. OA and FLU were extracted by a solid-liquid extraction procedure: after addition of hydrochloric acid, extraction used successively ethyl acetate, sodium hydroxide and chloroform. Liquid chromatography was performed on a 5 microm PuroSpher RP-18E cartridge using acetonitrile and 0.02 M aqueous orthophosphoric acid solution as mobile phase, with fluorescence detection. The performance of the method was established by spiking tissues with OA and FLU before the freeze-drying step. The method was linear over the concentration range 50-2000 ng/g freeze-dried tissue. Limits of detection and quantitation were 3.2 and 16 ng/g wet weight tissue respectively both for OA and FLU. Mean extraction recoveries of OA and FLU from freeze-dried tissue were 85.5 and 85.2% respectively. The method is suitable as a regulatory one for determination of residues of OA and FLU in freeze-dried salmon tissue.

  3. The CHROMEVALOA Database: A Resource for the Evaluation of Okadaic Acid Contamination in the Marine Environment Based on the Chromatin-Associated Transcriptome of the Mussel Mytilus galloprovincialis

    PubMed Central

    Suárez-Ulloa, Victoria; Fernández-Tajes, Juan; Aguiar-Pulido, Vanessa; Rivera-Casas, Ciro; González-Romero, Rodrigo; Ausio, Juan; Méndez, Josefina; Dorado, Julián; Eirín-López, José M.

    2013-01-01

    Okadaic Acid (OA) constitutes the main active principle in Diarrhetic Shellfish Poisoning (DSP) toxins produced during Harmful Algal Blooms (HABs), representing a serious threat for human consumers of edible shellfish. Furthermore, OA conveys critical deleterious effects for marine organisms due to its genotoxic potential. Many efforts have been dedicated to OA biomonitoring during the last three decades. However, it is only now with the current availability of detailed molecular information on DNA organization and the mechanisms involved in the maintenance of genome integrity, that a new arena starts opening up for the study of OA contamination. In the present work we address the links between OA genotoxicity and chromatin by combining Next Generation Sequencing (NGS) technologies and bioinformatics. To this end, we introduce CHROMEVALOAdb, a public database containing the chromatin-associated transcriptome of the mussel Mytilus galloprovincialis (a sentinel model organism) in response to OA exposure. This resource constitutes a leap forward for the development of chromatin-based biomarkers, paving the road towards the generation of powerful and sensitive tests for the detection and evaluation of the genotoxic effects of OA in coastal areas. PMID:23481679

  4. Roles of Organic Acid Anion Secretion in Aluminium Tolerance of Higher Plants

    PubMed Central

    Yang, Lin-Tong; Qi, Yi-Ping; Jiang, Huan-Xin; Chen, Li-Song

    2013-01-01

    Approximately 30% of the world's total land area and over 50% of the world's potential arable lands are acidic. Furthermore, the acidity of the soils is gradually increasing as a result of the environmental problems including some farming practices and acid rain. At mildly acidic or neutral soils, aluminium(Al) occurs primarily as insoluble deposits and is essentially biologically inactive. However, in many acidic soils throughout the tropics and subtropics, Al toxicity is a major factor limiting crop productivity. The Al-induced secretion of organic acid (OA) anions, mainly citrate, oxalate, and malate, from roots is the best documented mechanism of Al tolerance in higher plants. Increasing evidence shows that the Al-induced secretion of OA anions may be related to the following several factors, including (a) anion channels or transporters, (b) internal concentrations of OA anions in plant tissues, (d) temperature, (e) root plasma membrane (PM) H+-ATPase, (f) magnesium (Mg), and (e) phosphorus (P). Genetically modified plants and cells with higher Al tolerance by overexpressing genes for the secretion and the biosynthesis of OA anions have been obtained. In addition, some aspects needed to be further studied are also discussed. PMID:23509687

  5. Roles of organic acid anion secretion in aluminium tolerance of higher plants.

    PubMed

    Yang, Lin-Tong; Qi, Yi-Ping; Jiang, Huan-Xin; Chen, Li-Song

    2013-01-01

    Approximately 30% of the world's total land area and over 50% of the world's potential arable lands are acidic. Furthermore, the acidity of the soils is gradually increasing as a result of the environmental problems including some farming practices and acid rain. At mildly acidic or neutral soils, aluminium (Al) occurs primarily as insoluble deposits and is essentially biologically inactive. However, in many acidic soils throughout the tropics and subtropics, Al toxicity is a major factor limiting crop productivity. The Al-induced secretion of organic acid (OA) anions, mainly citrate, oxalate, and malate, from roots is the best documented mechanism of Al tolerance in higher plants. Increasing evidence shows that the Al-induced secretion of OA anions may be related to the following several factors, including (a) anion channels or transporters, (b) internal concentrations of OA anions in plant tissues, (d) temperature, (e) root plasma membrane (PM) H(+)-ATPase, (f) magnesium (Mg), and (e) phosphorus (P). Genetically modified plants and cells with higher Al tolerance by overexpressing genes for the secretion and the biosynthesis of OA anions have been obtained. In addition, some aspects needed to be further studied are also discussed.

  6. Organic acids from root exudates of banana help root colonization of PGPR strain Bacillus amyloliquefaciens NJN-6

    PubMed Central

    Yuan, Jun; Zhang, Nan; Huang, Qiwei; Raza, Waseem; Li, Rong; Vivanco, Jorge M.; Shen, Qirong

    2015-01-01

    The successful colonization of plant growth promoting rhizobacteria (PGPR) in the rhizosphere is an initial and compulsory step in the protection of plants from soil-borne pathogens. Therefore, it is necessary to evaluate the role of root exudates in the colonization of PGPR. Banana root exudates were analyzed by high pressure liquid chromatography (HPLC) which revealed exudates contained several organic acids (OAs) including oxalic, malic and fumaric acid. The chemotactic response and biofilm formation of Bacillus amyloliquefaciens NJN-6 were investigated in response to OA’s found in banana root exudates. Furthermore, the transcriptional levels of genes involved in biofilm formation, yqxM and epsD, were evaluated in response to OAs via quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Results suggested that root exudates containing the OAs both induced the chemotaxis and biofilm formation in NJN-6. In fact, the strongest chemotactic and biofilm response was found when 50 μM of OAs were applied. More specifically, malic acid showed the greatest chemotactic response whereas fumaric acid significantly induced biofilm formation by a 20.7–27.3% increase and therefore biofilm formation genes expression. The results showed banana root exudates, in particular the OAs released, play a crucial role in attracting and initiating PGPR colonization on the host roots. PMID:26299781

  7. Ursolic and oleanolic acids as antimicrobial and immunomodulatory compounds for tuberculosis treatment

    PubMed Central

    2013-01-01

    Background New alternatives for the treatment of Tuberculosis (TB) are urgently needed and medicinal plants represent a potential option. Chamaedora tepejilote and Lantana hispida are medicinal plants from Mexico and their hexanic extracts have shown antimycobacterial activity. Bioguided investigation of these extracts showed that the active compounds were ursolic acid (UA) and oleanolic acid (OA). Methods The activity of UA and OA against Mycobacterium tuberculosis H37Rv, four monoresistant strains, and two drug-resistant clinical isolates were determined by MABA test. The intracellular activity of UA and OA against M. tuberculosis H37Rv and a MDR clinical isolate were evaluated in a macrophage cell line. Finally, the antitubercular activity of UA and OA was tested in BALB/c mice infected with M. tuberculosis H37Rv or a MDR strain, by determining pulmonary bacilli loads, tissue damage by automated histomorphometry, and expression of IFN-γ, TNF-α, and iNOS by quantitative RT-PCR. Results The in vitro assay showed that the UA/OA mixture has synergistic activity. The intracellular activity of these compounds against M. tuberculosis H37Rv and a MDR clinical isolate in a macrophage cell line showed that both compounds, alone and in combination, were active against intracellular mycobacteria even at low doses. Moreover, when both compounds were used to treat BALB/c mice with TB induced by H37Rv or MDR bacilli, a significant reduction of bacterial loads and pneumonia were observed compared to the control. Interestingly, animals treated with UA and OA showed a higher expression of IFN-γ and TNF-α in their lungs, than control animals. Conclusion UA and OA showed antimicrobial activity plus an immune-stimulatory effect that permitted the control of experimental pulmonary TB. PMID:24098949

  8. Association of plasma n-6 and n-3 polyunsaturated fatty acids with synovitis in the knee: the MOST study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In osteoarthritis (OA) the synovium is often inflamed and inflammatory cytokines contribute to cartilage damage. Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have anti-inflammatory effects whereas omega-6 polyunsaturated fatty acids (n-6 PUFAs) have, on balance, proinflammatory effects. The goal ...

  9. Interleukin-1β induced Stress Granules Sequester COX-2 mRNA and Regulates its Stability and Translation in Human OA Chondrocytes

    PubMed Central

    Ansari, Mohammad Y.; Haqqi, Tariq M.

    2016-01-01

    Enhanced and immediate expression of cyclooxygenase-2 (COX-2) mRNA is observed in IL-1β-stimulated OA chondrocytes but the synthesis of protein found significantly delayed. Here we investigated the role of stress granules (SGs), ribonucleoprotein complexes that regulate mRNA translation, in the delayed translation of COX-2 mRNAs in IL-1β-stimulated OA chondrocytes. Stimulation of human chondrocytes with IL-1β activated the stress response genes and the phosphorylation of eIF2α that triggered the assembly of SGs. Using combined immunofluorescence staining of SGs markers and COX-2 protein, RNA fluorescence in situ hybridization and RNA immunoprecipitation, the COX-2 mRNAs were found sequestered in SGs in IL-1β-stimulated OA chondrocytes. No increase in COX-2 protein expression was observed during the persistence of SGs but enhanced expression of COX-2 protein was noted upon clearance of the SGs. Inhibition of SGs clearance blocked COX-2 mRNA translation whereas blocking the assembly of SGs by TIA-1 depletion resulted in rapid and increased production of COX-2 and PGE2. Our findings show for the first time assembly of SGs and sequestration of COX-2 mRNAs in human OA chondrocytes under pathological conditions. Post-transcriptional regulation of COX-2 mRNAs translation by SGs indicates a role in IL-1β-mediated catabolic response that could be therapeutically targeted in OA. PMID:27271770

  10. Pre-harvest application of oxalic acid increases quality and resistance to Penicillium expansum in kiwifruit during postharvest storage.

    PubMed

    Zhu, Yuyan; Yu, Jie; Brecht, Jeffrey K; Jiang, Tianjia; Zheng, Xiaolin

    2016-01-01

    Kiwifruit (Actinidia deliciosa cv. Bruno) fruits were sprayed with 5mM oxalic acid (OA) at 130, 137, and 144 days after full blossom, and then harvested at commercial maturity [soluble solid content (SSC) around 10.0%] and stored at room temperature (20 ± 1 °C). Pre-harvest application of OA led to fruit with higher ascorbic acid content at harvest, slowed the decreases in fruit firmness and ascorbic acid content and increase in SSC during storage, and also decreased the natural disease incidence, lesion diameter, and patulin accumulation in fruit inoculated with Penicillium expansum, indicating that the OA treatment increased quality and induced disease resistance in kiwifruit. It was suggested that the increase in activities of defense-related enzymes and in levels of substances related to disease resistance might collectively contribute to resistance in kiwifruit against fungi such as P. expansum in storage.

  11. Profiles of fatty acids and 7-O-acyl okadaic acid esters in bivalves: can bacteria be involved in acyl esterification of okadaic acid?

    PubMed

    Vale, Paulo

    2010-01-01

    The presence of 7-O-acyl okadaic acid (OA) esters was studied by LC-MS in the digestive glands of blue mussel (Mytilus galloprovincialis) and common cockle (Cerastoderma edule) from Albufeira lagoon, located 20km south of Lisbon. The profile of free and total fatty acids (FA) was analysed using a similar LC separation with a reversed phase C8 column and mass spectrometry detection. In mussel the free FA profile was reflected in the FA esterified to OA, being palmitic acid for instance the most abundant in both cases. In cockle, 7-O-acyl esters with palmitic acid were almost absent and esters with a C16:0 isomer were dominant, followed by esters with C15:1 and C15:0. The cockle free FA profile was similar to mussel, and in accordance with literature findings in bivalves. After hydrolysis, a major difference in the FA profile occurred in both species, presenting a high percentage of a C16:0 isomer. The isomer found in general lipids and bound to OA seemed to be related, presenting similar relative retention times (RRT) to C16:0, differing from expected RRT of monomethyl-branched isomers (iso- or anteiso-). A tentative identification was made with the multimethyl-branched isoprenoid, 4,8,12-trimethyltridecanoic acid (TMTD). TMTD is a product of phytol degradation. This was also suspected when the proportion of this compound in relation to palmitic acid was reduced in vivo in mussels fed a chlorophyll-free diet. Extensive esterification of OA by, among others, phytol-degrading bacteria is discussed as a plausible hypothesis in cockle, but not in mussel, due to the relatively high specific proportion of odd-numbered and branched FA.

  12. Molecular Mechanisms of Selenium Tolerance and Hyperaccumulation in Stanleya pinnata1[W][OA

    PubMed Central

    Freeman, John L.; Tamaoki, Masanori; Stushnoff, Cecil; Quinn, Colin F.; Cappa, Jennifer J.; Devonshire, Jean; Fakra, Sirine C.; Marcus, Matthew A.; McGrath, Steve P.; Van Hoewyk, Doug; Pilon-Smits, Elizabeth A.H.

    2010-01-01

    The molecular mechanisms responsible for selenium (Se) tolerance and hyperaccumulation were studied in the Se hyperaccumulator Stanleya pinnata (Brassicaceae) by comparing it with the related secondary Se accumulator Stanleya albescens using a combination of physiological, structural, genomic, and biochemical approaches. S. pinnata accumulated 3.6-fold more Se and was tolerant to 20 μm selenate, while S. albescens suffered reduced growth, chlorosis and necrosis, impaired photosynthesis, and high levels of reactive oxygen species. Levels of ascorbic acid, glutathione, total sulfur, and nonprotein thiols were higher in S. pinnata, suggesting that Se tolerance may in part be due to increased antioxidants and up-regulated sulfur assimilation. S. pinnata had higher selenocysteine methyltransferase protein levels and, judged from liquid chromatography-mass spectrometry, mainly accumulated the free amino acid methylselenocysteine, while S. albescens accumulated mainly the free amino acid selenocystathionine. S. albescens leaf x-ray absorption near-edge structure scans mainly detected a carbon-Se-carbon compound (presumably selenocystathionine) in addition to some selenocysteine and selenate. Thus, S. albescens may accumulate more toxic forms of Se in its leaves than S. pinnata. The species also showed different leaf Se sequestration patterns: while S. albescens showed a diffuse pattern, S. pinnata sequestered Se in localized epidermal cell clusters along leaf margins and tips, concentrated inside of epidermal cells. Transcript analyses of S. pinnata showed a constitutively higher expression of genes involved in sulfur assimilation, antioxidant activities, defense, and response to (methyl)jasmonic acid, salicylic acid, or ethylene. The levels of some of these hormones were constitutively elevated in S. pinnata compared with S. albescens, and leaf Se accumulation was slightly enhanced in both species when these hormones were supplied. Thus, defense-related phytohormones

  13. In Vivo Packaging of Triacylglycerols Enhances Arabidopsis Leaf Biomass and Energy Density1[W][OA

    PubMed Central

    Winichayakul, Somrutai; Scott, Richard William; Roldan, Marissa; Hatier, Jean-Hugues Bertrand; Livingston, Sam; Cookson, Ruth; Curran, Amy Christina; Roberts, Nicholas John

    2013-01-01

    Our dependency on reduced carbon for energy has led to a rapid increase in the search for sustainable alternatives and a call to focus on energy densification and increasing biomass yields. In this study, we generated a uniquely stabilized plant structural protein (cysteine [Cys]-oleosin) that encapsulates triacylglycerol (TAG). When coexpressed with diacylglycerol O-acyltransferase (DGAT1) in Arabidopsis (Arabidopsis thaliana), we observed a 24% increase in the carbon dioxide (CO2) assimilation rate per unit of leaf area and a 50% increase in leaf biomass as well as approximately 2-, 3-, and 5-fold increases in the fatty acid content of the mature leaves, senescing leaves, and roots, respectively. We propose that the coexpression led to the formation of enduring lipid droplets that prevented the futile cycle of TAG biosynthesis/lipolysis and instead created a sustained demand for de novo lipid biosynthesis, which in turn elevated CO2 recycling in the chloroplast. Fatty acid profile analysis indicated that the formation of TAG involved acyl cycling in Arabidopsis leaves and roots. We also demonstrate that the combination of Cys-oleosin and DGAT1 resulted in the highest accumulation of fatty acids in the model single-cell eukaryote, Saccharomyces cerevisiae. Our results support the notion that the prevention of lipolysis is vital to enabling TAG accumulation in vegetative tissues and confirm the earlier speculation that elevating fatty acid biosynthesis in the leaf would lead to an increase in CO2 assimilation. The Cys-oleosins have applications in biofuels, animal feed, and human nutrition as well as in providing a tool for investigating fatty acid biosynthesis and catabolism. PMID:23616604

  14. Metabolic pathways regulated by abscisic acid, salicylic acid and γ-aminobutyric acid in association with improved drought tolerance in creeping bentgrass (Agrostis stolonifera).

    PubMed

    Li, Zhou; Yu, Jingjin; Peng, Yan; Huang, Bingru

    2017-01-01

    Abscisic acid (ABA), salicylic acid (SA) and γ-aminobutyric acid (GABA) are known to play roles in regulating plant stress responses. This study was conducted to determine metabolites and associated pathways regulated by ABA, SA and GABA that could contribute to drought tolerance in creeping bentgrass (Agrostis stolonifera). Plants were foliar sprayed with ABA (5 μM), GABA (0.5 mM) and SA (10 μM) or water (untreated control) prior to 25 days drought stress in controlled growth chambers. Application of ABA, GABA or SA had similar positive effects on alleviating drought damages, as manifested by the maintenance of lower electrolyte leakage and greater relative water content in leaves of treated plants relative to the untreated control. Metabolic profiling showed that ABA, GABA and SA induced differential metabolic changes under drought stress. ABA mainly promoted the accumulation of organic acids associated with tricarboxylic acid cycle (aconitic acid, succinic acid, lactic acid and malic acid). SA strongly stimulated the accumulation of amino acids (proline, serine, threonine and alanine) and carbohydrates (glucose, mannose, fructose and cellobiose). GABA enhanced the accumulation of amino acids (GABA, glycine, valine, proline, 5-oxoproline, serine, threonine, aspartic acid and glutamic acid) and organic acids (malic acid, lactic acid, gluconic acid, malonic acid and ribonic acid). The enhanced drought tolerance could be mainly due to the enhanced respiration metabolism by ABA, amino acids and carbohydrates involved in osmotic adjustment (OA) and energy metabolism by SA, and amino acid metabolism related to OA and stress-defense secondary metabolism by GABA.

  15. Oleic acid content is responsible for the reduction in blood pressure induced by olive oil.

    PubMed

    Terés, S; Barceló-Coblijn, G; Benet, M; Alvarez, R; Bressani, R; Halver, J E; Escribá, P V

    2008-09-16

    Numerous studies have shown that high olive oil intake reduces blood pressure (BP). These positive effects of olive oil have frequently been ascribed to its minor components, such as alpha-tocopherol, polyphenols, and other phenolic compounds that are not present in other oils. However, in this study we demonstrate that the hypotensive effect of olive oil is caused by its high oleic acid (OA) content (approximately 70-80%). We propose that olive oil intake increases OA levels in membranes, which regulates membrane lipid structure (H(II) phase propensity) in such a way as to control G protein-mediated signaling, causing a reduction in BP. This effect is in part caused by its regulatory action on G protein-associated cascades that regulate adenylyl cyclase and phospholipase C. In turn, the OA analogues, elaidic and stearic acids, had no hypotensive activity, indicating that the molecular mechanisms that link membrane lipid structure and BP regulation are very specific. Similarly, soybean oil (with low OA content) did not reduce BP. This study demonstrates that olive oil induces its hypotensive effects through the action of OA.

  16. Lack of DNA damage induction by okadaic acid, a marine toxin, in the CHO-Hprt and the in vitro UDS assays.

    PubMed

    Le Hégarat, Ludovic; Nesslany, Fabrice; Mourot, Annick; Marzin, Daniel; Fessard, Valérie

    2004-12-12

    Okadaic acid (OA) is a marine toxin produced by dinoflagellates and responsible for human intoxications. OA is a specific inhibitor of serine/threonine protein phosphatases PP1 and PP2A and a potent tumor promoter in mouse skin and rat glandular stomach. In a previous study, we demonstrated that OA induced aneuploidy in CHO-K1 cells using the cytokinesis-block micronucleus (CBMN) assay coupled to FISH and concluded that OA was not a direct mutagen. As some previous in vitro mutagenicity studies had given positive results with OA, we decided to perform two additional in vitro mutagenicity assays in accordance with the OECD guidelines: (i) the CHO/Hprt test, which provides end points about locus-specific gene mutation; (ii) the in vitro unscheduled DNA synthesis (UDS) assay in rat hepatocytes, which measures [(3)H]thymidine incorporation into DNA undergoing excision repair. In the CHO/Hprt assay, there was no significant increase in the number of mutants for doses ranging from 5 to 5000 nM in the presence or absence of rat liver S9 fraction. In the in vitro UDS assay, OA did not induce primary DNA damages in rat hepatocytes following 18 h exposure at concentrations between 1.32 and 100 nM. As OA could affect the DNA repair systems via the inhibition of protein phosphatases, its effects on the repair kinetic of 2AAF-induced DNA damage were also investigated with the UDS assay. The results showed that OA did not interact with the DNA-repair process involved in in vitro UDS in rat hepatocytes. We concluded that OA failed to induce direct DNA damage but acted principally by altering the chromosome number, which could contribute to its carcinogenic effect.

  17. The methyl ester of okadaic acid is more potent than okadaic acid in disrupting the actin cytoskeleton and metabolism of primary cultured hepatocytes

    PubMed Central

    Espiña, Begoña; Louzao, MCarmen; Cagide, Eva; Alfonso, Amparo; Vieytes, Mercedes R; Yasumoto, Takeshi; Botana, Luis M

    2010-01-01

    Background and purpose: Okadaic acid (OA) and microcystins (MCs) are structurally different toxins with the same mechanism of action, inhibition of serine/threonine protein phosphatases (PPs). Methyl okadaate (MeOk), a methyl ester derivative of OA, was considered almost inactive due to its weak inhibition of PP1 and PP2A. Here, we have investigated the activity and potency of MeOk in hepatic cells in comparison with that of OA and MCs. Experimental approach: We tested the effects of MeOK, OA and microcystin-leucine and arginine (MC-LR) on the metabolic rate, the actin cytoskeleton and glucose uptake in a rat hepatocyte cell line (Clone 9) and in primary cultured rat hepatocytes. PP2A was assayed to compare OA and MeOk activity. Key results: MeOk disrupted the actin cytoskeleton and depressed the metabolic rate of both types of rat hepatocytes, being six-fold less potent than OA in Clone 9 cells but nearly six-fold more potent in primary cultured hepatocytes. However, unlike OA, MeOk did not change glucose uptake in these cells, suggesting a weak inhibition of PP2A, as confirmed in direct assays of PP2A activity. Conclusions and implications: Although MeOk was originally described as a weakly bioactive molecule, it clearly depressed the metabolic rate and disrupted the cytoskeleton in primary and immortalized rat hepatocytes. Furthermore, MeOk affected primary hepatocytes at much lower concentrations than those affecting immortalized cells. These effects were unrelated to PP2A inhibition. Our results suggest the risk to public health from MeOk in foodstuffs should be re-evaluated. PMID:20015092

  18. Detection of okadaic acid and related esters in mussels during diarrhetic shellfish poisoning (DSP) episodes in Greece using the mouse bioassay, the PP2A inhibition assay and HPLC with fluorimetric detection.

    PubMed

    Prassopoulou, Eleanna; Katikou, Panagiota; Georgantelis, Dimitrios; Kyritsakis, Apostolos

    2009-02-01

    An approach involving chemical, functional and biological techniques was taken for the detection and quantification of the marine toxin okadaic acid (OA) in mussels from Thermaikos and Saronikos Gulfs, Greece, during DSP episodes that occurred in 2006-2007. Samples were analyzed using the mouse bioassay, high performance liquid chromatography with fluorimetric detection (HPLC-FLD), using l-bromoacetylpyrene (BAP), as a precolumn derivatisation reagent, and the protein phosphatase 2A inhibition assay (PP2AIA) using a commercially available kit. Okadaic acid (OA) and its polar and non-polar esters were detected and quantified by HPLC-FLD, after hydrolysis of the samples during preparation. The detection limit of the HPLC method for OA was 5.86 microg OA/kg, which permits this method to be used for the regulatory control of these toxins in shellfish. Comparison of the results by all three methods revealed excellent consistency.

  19. Occurrence of Lipophilic Marine Toxins in Shellfish from Galicia (NW of Spain) and Synergies among Them

    PubMed Central

    Rodríguez, Laura P.; González, Virginia; Martínez, Aníbal; Paz, Beatriz; Lago, Jorge; Cordeiro, Victoria; Blanco, Lucía; Vieites, Juan Manuel; Cabado, Ana G.

    2015-01-01

    Lipophilic marine toxins pose a serious threat for consumers and an enormous economic problem for shellfish producers. Synergistic interaction among toxins may play an important role in the toxicity of shellfish and consequently in human intoxications. In order to study the toxic profile of molluscs, sampled during toxic episodes occurring in different locations in Galicia in 2014, shellfish were analyzed by liquid chromatography tandem mass spectrometry (LC–MS/MS), the official method for the detection of lipophilic toxins. The performance of this procedure was demonstrated to be fit for purpose and was validated in house following European guidelines. The vast majority of toxins present in shellfish belonged to the okadaic acid (OA) group and some samples from a particular area contained yessotoxin (YTX). Since these toxins occur very often with other lipophilic toxins, we evaluated the potential interactions among them. A human neuroblastoma cell line was used to study the possible synergies of OA with other lipophilic toxins. Results show that combination of OA with dinophysistoxin 2 (DTX2) or YTX enhances the toxicity triggered by OA, decreasing cell viability and cell proliferation, depending on the toxin concentration and incubation time. The effects of other lipophilic toxins as 13-desmethyl Spirolide C were also evaluated in vitro. PMID:25815891

  20. Development of Certified Reference Materials for Diarrhetic Shellfish Poisoning Toxins, Part 1: Calibration Solutions.

    PubMed

    Beach, Daniel G; Crain, Sheila; Lewis, Nancy; LeBlanc, Patricia; Hardstaff, William R; Perez, Ruth A; Giddings, Sabrina D; Martinez-Farina, Camilo F; Stefanova, Roumiana; Burton, Ian W; Kilcoyne, Jane; Melanson, Jeremy E; Quilliam, Michael A; McCarron, Pearse

    2016-09-01

    Okadaic acid (OA) and its analogs dinophysistoxins-1 (DTX1) and -2 (DTX2) are lipophilic polyethers produced by marine dinoflagellates. These toxins accumulate in shellfish and cause diarrhetic shellfish poisoning (DSP) in humans. Regulatory testing of shellfish is essential to safeguard public health and for international trade. Certified reference materials (CRMs) play a key role in analytical monitoring programs. This paper presents an overview of the interdisciplinary work that went into the planning, production, and certification of calibration-solution CRMs for OA, DTX1, and DTX2. OA and DTX1 were isolated from large-scale algal cultures and DTX2 from naturally contaminated mussels. Toxins were isolated by a combination of extraction and chromatographic steps with processes adapted to suit the source and concentration of each toxin. New 19-epi-DSP toxin analogs were identified as minor impurities. Once OA, DTX1, and DTX2 were established to be of suitable purity, solutions were prepared and dispensed into flame-sealed glass ampoules. Certification measurements were carried out using quantitative NMR spectroscopy and LC-tandem MS. Traceability of measurements was established through certified external standards of established purity. Uncertainties were assigned following standards and guidelines from the International Organization for Standardization, with components from the measurement, stability, and homogeneity studies being propagated into final combined uncertainties.

  1. Occurrence of diarrhetic shellfish poisoning (DSP) toxins in clams (Ruditapes decussatus) from Tunis north lagoon.

    PubMed

    Armi, Zina; Turki, Souad; Trabelsi, Elbahri; Ceredi, Alfiero; Riccardi, Elena; Milandri, Anna

    2012-08-01

    The main diarrhetic shellfish toxins, okadaic acid (OA) and dinophysistoxin-1, 2 (DTX-2, 2) were detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) as pyrenacyl esters in clams (Ruditapes decussatus) collected in Tunis north lagoon from January 2007 to June 2008. Sample analyses by LC-MS/MS displayed OA and related congeners (DTX-2, 2) with a highest detected level of 21 μg OA eq/kg shellfish meat for the samples of January 2007. Nevertheless, all samples were MBA negative. During the study period, potentially toxic dinoflagellate Dinophysis sacculus was recorded all year, blooming at different times. Highest concentrations were recorded during January 2007 with 4.6 × 10(4) cells per liter and 4.10(4) cells per liter in the northern and southern districts, respectively. Results show that there is no significant correlation between D. sacculus densities in water column and diarrhetic shellfish poisoning (DSP) toxins concentrations unregistered in clams. These data reveal that DSP toxicity in clams of Tunis north lagoon is low according to European regulatory limit (160 μg OA eq/kg shellfish meat). However, a potential threat, in this area, is represented by DSP toxic species as D. sacculus and provides grounds for widen and reinforcing sanitary control of the phycotoxin measures in the region.

  2. Occurrence of lipophilic marine toxins in shellfish from Galicia (NW of Spain) and synergies among them.

    PubMed

    Rodríguez, Laura P; González, Virginia; Martínez, Aníbal; Paz, Beatriz; Lago, Jorge; Cordeiro, Victoria; Blanco, Lucía; Vieites, Juan Manuel; Cabado, Ana G

    2015-03-25

    Lipophilic marine toxins pose a serious threat for consumers and an enormous economic problem for shellfish producers. Synergistic interaction among toxins may play an important role in the toxicity of shellfish and consequently in human intoxications. In order to study the toxic profile of molluscs, sampled during toxic episodes occurring in different locations in Galicia in 2014, shellfish were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS), the official method for the detection of lipophilic toxins. The performance of this procedure was demonstrated to be fit for purpose and was validated in house following European guidelines. The vast majority of toxins present in shellfish belonged to the okadaic acid (OA) group and some samples from a particular area contained yessotoxin (YTX). Since these toxins occur very often with other lipophilic toxins, we evaluated the potential interactions among them. A human neuroblastoma cell line was used to study the possible synergies of OA with other lipophilic toxins. Results show that combination of OA with dinophysistoxin 2 (DTX2) or YTX enhances the toxicity triggered by OA, decreasing cell viability and cell proliferation, depending on the toxin concentration and incubation time. The effects of other lipophilic toxins as 13-desmethyl Spirolide C were also evaluated in vitro.

  3. Marked Synergistic Bactericidal Effects and Mode of Action of Medium-Chain Fatty Acids in Combination with Organic Acids against Escherichia coli O157:H7

    PubMed Central

    Kim, S. A.

    2013-01-01

    The aim of this study was to examine the synergistic bactericidal effects of medium-chain fatty acids (MCFAs; caprylic, capric, and lauric acid) and organic acids (OAs; acetic, lactic, malic, and citric acid) against Escherichia coli O157:H7 and to identify their underlying mechanism(s) of action. E. coli O157:H7 was treated with MCFAs, OAs, or different combinations of MCFAs and OAs. Membrane damage and cell morphology were examined by flow cytometry and transmission electron microscopy, respectively. Combined treatment resulted in an additional log-unit reduction compared with the sum of the reductions obtained after individual treatment. For example, caprylic acid (1.0 mM, or 0.016%) and citric acid (1.0 mM, or 0.012%) alone showed negligible bactericidal effects (0.30- and 0.06-log-unit reductions, respectively); however, a marked synergistic effect (>7.15-log-unit reduction) was observed when the two were combined. Although flow cytometry and microscopic analyses of bacteria treated with individual MCFAs and OAs showed evidence of membrane disruption, the bacteria were still able to form colonies; thus, the cell damage was recoverable. In contrast, cells exposed to combined treatments showed clear membrane disintegration and/or cell death (irreversible damage). The mechanism underlying the antimicrobial effects of combined treatment with MCFAs or OAs may involve disruption of the bacterial membrane, which then facilitates the entry of other antimicrobial compounds into the cytoplasm. The main advantage of combined treatment with very low concentrations of natural antimicrobial compounds is that it is very cost-effective. Thus, this approach may be an alternative to more conventional antimicrobial treatments, such as those currently used in public health, medical centers, and the food industry. PMID:23956396

  4. Carbon and Nitrogen Provisions Alter the Metabolic Flux in Developing Soybean Embryos1[W][OA

    PubMed Central

    Allen, Doug K.; Young, Jamey D.

    2013-01-01

    Soybean (Glycine max) seeds store significant amounts of their biomass as protein, levels of which reflect the carbon and nitrogen received by the developing embryo. The relationship between carbon and nitrogen supply during filling and seed composition was examined through a series of embryo-culturing experiments. Three distinct ratios of carbon to nitrogen supply were further explored through metabolic flux analysis. Labeling experiments utilizing [U-13C5]glutamine, [U-13C4]asparagine, and [1,2-13C2]glucose were performed to assess embryo metabolism under altered feeding conditions and to create corresponding flux maps. Additionally, [U-14C12]sucrose, [U-14C6]glucose, [U-14C5]glutamine, and [U-14C4]asparagine were used to monitor differences in carbon allocation. The analyses revealed that: (1) protein concentration as a percentage of total soybean embryo biomass coincided with the carbon-to-nitrogen ratio; (2) altered nitrogen supply did not dramatically impact relative amino acid or storage protein subunit profiles; and (3) glutamine supply contributed 10% to 23% of the carbon for biomass production, including 9% to 19% of carbon to fatty acid biosynthesis and 32% to 46% of carbon to amino acids. Seed metabolism accommodated different levels of protein biosynthesis while maintaining a consistent rate of dry weight accumulation. Flux through ATP-citrate lyase, combined with malic enzyme activity, contributed significantly to acetyl-coenzyme A production. These fluxes changed with plastidic pyruvate kinase to maintain a supply of pyruvate for amino and fatty acids. The flux maps were independently validated by nitrogen balancing and highlight the robustness of primary metabolism. PMID:23314943

  5. Host-guest inclusion system of oleanolic acid with methyl-β-cyclodextrin: Preparation, characterization and anticancer activity

    NASA Astrophysics Data System (ADS)

    Ren, Yufeng; Liu, Ying; Niu, Raomei; Liao, Xiali; Zhang, Jihong; Yang, Bo

    2016-08-01

    In this study, the solid inclusion complex of oleanolic acid (OA) with methyl-β-cyclodextrin (M-β-CD) was prepared and characterized by nuclear magnetic resonance (NMR), X-ray diffraction (XRD), scanning electron microscope (SEM) and differential scanning calorimetry (DSC). The inclusion behaviors of OA/M-β-CD complex were studied by fluorescence spectroscopy and the Job plot, which indicated a 1:1 inclusion mode between OA and M-β-CD. The stability constant (Ks) of the complex was 1072.30 ± 20 M-1 determined by spectral titration at 25 °C. Besides, the water solubility of OA was significantly increased to 8.2 mg/mL by inclusion complexation, compared to only ca. 0.012 μg/mL of free OA. The in vitro cytotoxicity of the inclusion complex was noticeably better than that of native OA with the IC50 values of 8.89, 7.89 and 5.77 μM on human cancer cell lines HepG2, HT29 and HCT116, respectively, by MTT assay.

  6. Rebamipide Attenuates Mandibular Condylar Degeneration in a Murine Model of TMJ-OA by Mediating a Chondroprotective Effect and by Downregulating RANKL-Mediated Osteoclastogenesis

    PubMed Central

    Izawa, Takashi; Mori, Hiroki; Shinohara, Tekehiro; Mino-Oka, Akiko; Hutami, Islamy Rahma; Iwasa, Akihiko; Tanaka, Eiji

    2016-01-01

    Temporomandibular joint osteoarthritis (TMJ-OA) is characterized by progressive degradation of cartilage and changes in subchondral bone. It is also one of the most serious subgroups of temporomandibular disorders. Rebamipide is a gastroprotective agent that is currently used for the treatment of gastritis and gastric ulcers. It scavenges reactive oxygen radicals and has exhibited anti-inflammatory potential. The aim of this study was to investigate the impact of rebamipide both in vivo and in vitro on the development of cartilage degeneration and osteoclast activity in an experimental murine model of TMJ-OA, and to explore its mode of action. Oral administration of rebamipide (0.6 mg/kg and 6 mg/kg) was initiated 24 h after TMJ-OA was induced, and was maintained daily for four weeks. Rebamipide treatment was found to attenuate cartilage degeneration, to reduce the number of apoptotic cells, and to decrease the expression levels of matrix metalloproteinase-13 (MMP-13) and inducible nitric oxide synthase (iNOS) in TMJ-OA cartilage in a dose-dependent manner. Rebamipide also suppressed the activation of transcription factors (e.g., NF-κB, NFATc1) and mitogen-activated protein kinases (MAPK) by receptor activator of nuclear factor kappa-B ligand (RANKL) to inhibit the differentiation of osteoclastic precursors, and disrupted the formation of actin rings in mature osteoclasts. Together, these results demonstrate the inhibitory effects of rebamipide on cartilage degradation in experimentally induced TMJ-OA. Furthermore, suppression of oxidative damage, restoration of extracellular matrix homeostasis of articular chondrocytes, and reduced subchondral bone loss as a result of blocked osteoclast activation suggest that rebamipide is a potential therapeutic strategy for TMJ-OA. PMID:27123995

  7. OAS and PKR are not required for the antiviral effect of Ad:IFN-gamma against acute HSV-1 in primary trigeminal ganglia cultures.

    PubMed

    Austin, Bobbie Ann; Halford, William; Silverman, Robert H; Williams, Bryan R G; Carr, Daniel J J

    2006-04-01

    Three interferon-gamma (IFN-gamma)-induced antiviral pathways have been reported. Involved antiviral proteins include: Mx, RNase L/2',5'-OAS, and protein kinase R (PKR). Involvement of OAS and PKR in IFN-gamma-induced anti-herpes simplex virus-1 (HSV-1) pathways has not been reported previously, but IFN-gamma induces OAS and PKR when other viruses invade the nervous system. The aim of the current study was to determine if the absence of intact OAS and PKR antiviral pathways affects the antiviral activity of IFN-gamma during acute HSV-1 infection within the trigeminal ganglia (TG). To investigate this, primary TG cultures were established using TGs removed from C57BL/6 (wild-type), RNase L knockout, and RNase L/PKR double knockout mice. Each dissociated TG was transduced with an adenoviral vector containing an IFN-gamma transgene or vector alone. Viral titers after HSV-1 infection of primary TG cell cultures were determined. Significant differences in viral titer for Ad:Null-transduced vs. Ad:IFN-gamma-tranduced TG were found in each genotype. However, the effectiveness of Ad:IFN-gamma was not reduced in the absence of both OAS and PKR pathways or OAS alone. Recombinant IFN-gamma also exhibited anti-HSV-1 activity. The effectiveness of the IFN-gamma transgene was lost in primary TG cells from IFN-gamma receptor knockout mice. The data suggest that novel anti-HSV-1 mechanisms are induced by IFN-gamma.

  8. Caveolin-1 plays a key role in the oleanolic acid-induced apoptosis of HL-60 cells.

    PubMed

    Ma, Wei; Wang, Di-Di; Li, Li; Feng, Yu-Kuan; Gu, Hong-Mei; Zhu, Gui-Ming; Piao, Jin-Hua; Yang, Yu; Gao, Xu; Zhang, Peng-Xia

    2014-07-01

    Our previous study found that caveolin-1 (CAV-1) protein expression is upregulated during oleanolic acid (OA)-induced inhibition of proliferation and promotion of apoptosis in HL-60 cells. CAV-1 is the main structural protein component of caveolae, playing important roles in tumorigenesis and tumor development. It has been shown that cav-1 expression is lower in leukemia cancer cell lines SUP-B15, HL-60, THP-1 and K562 and in chronic lymphocytic leukemia primary (CLP) cells when compared with normal white blood cells, with the lowest cav-1 expression level found in HL-60 cells. To study the effects of cav-1 in HL-60 cells and the effects of cav-1 overexpression on OA drug efficacy, cav-1 was overexpressed in HL-60 cells using lentiviral-mediated transfection combined with OA treatment. The results showed that cav-1 overexpression inhibited HL-60 cell proliferation, promoted apoptosis, arrested the cell cycle in the G1 phase and inhibited activation of the PI3K/AKT/mTOR signaling pathway. Overexpression of CAV-1 also increased HL-60 cell sensitivity to OA. To further verify whether OA affects HL-60 cells via the activation of downstream signaling pathways by CAV-1, cav-1 gene expression was silenced using RNAi, and the cells were treated with OA to examine its efficacy. The results showed that after cav-1 silencing, OA had little effect on cell activity, apoptosis, the cell cycle and phosphorylation of HL-60 cells. This study is the first to show that CAV-1 plays a crucial role in the effects of OA on HL-60 cells.

  9. Development of a novel immunobiosensor method for the rapid detection of okadaic acid contamination in shellfish extracts.

    PubMed

    Llamas, Nuria M; Stewart, Linda; Fodey, Terry; Higgins, H Cowan; Velasco, María Luisa R; Botana, Luis M; Elliott, Christopher T

    2007-09-01

    The mouse bioassay is the methodology that is most widely used to detect okadaic acid (OA) in shellfish samples. This is one of the best-known toxins, and it belongs to the family of marine biotoxins referred to as the diarrhetic shellfish poisons (DSP). Due to animal welfare concerns, alternative methods of toxin detection are being sought. A rapid and specific biosensor immunoassay method was developed and validated for the detection of OA. An optical sensor instrument based on the surface plasmon resonance (SPR) phenomenon was utilised. A polyclonal antibody to OA was raised against OA-bovine thyroglobulin conjugate and OA-N-hydroxy succinimide ester was immobilised onto an amine sensor chip surface. The assay parameters selected for the analysis of the samples were: antibody dilution, 1/750; ratio of antibody to standard, 1:1; volume of sample injected, 25 microl min(-1); flow rate, 25 microl min(-1). An assay action limit of 126 ng g(-1) was established by analysing of 20 shellfish samples spiked with OA at the critical concentration of 160 ng g(-1), which is the action limit established by the European Union (EU). At this concentration of OA, the assay delivered coefficient of variations (CVs) of <10%. The chip surface developed was shown to be highly stable, allowing more than 50 analyses per channel. When the concentrations of OA determined with the biosensor method were compared with the values obtained by LC-MS in contaminated shellfish samples, the correlation between the two analytical methods was found to be highly satisfactory (r(2) = 0.991).

  10. The preparation of CeF{sub 3} nanocluster capped with oleic acid by extraction method and application to lithium grease

    SciTech Connect

    Wang Libo; Zhang Ming; Wang Xiaobo; Liu Weimin

    2008-08-04

    CeF{sub 3} nanocluster surface-capped with oleic acid (coded as OA-CeF{sub 3}) were prepared using extraction method. The resulting OA-CeF{sub 3} nanocluster was characterized by means of transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transformation infrared spectrometry (FTIR), and X-ray photoelectron spectroscopy (XPS). The effect of the OA-CeF{sub 3} nanocluster as an additive in synthetic lithium grease was investigated using a four-ball friction and wear tester. It was found that the as-prepared OA-CeF{sub 3} nanocluster had a broad size distribution, with the average diameter to be about 20 nm, which was confirmed by both the XRD and TEM analytical results. The oleic acid as the capping agent was chemically bonded to the CeF{sub 3} nanocores via strong chemical interaction. The OA-CeF{sub 3} nanocluster as the additive led to an obvious improvement in the antiwear and extreme pressure properties of the synthetic lithium grease. However, the OA-CeF{sub 3} nanocluster as the additive had little effect on the friction-reducing behavior of the lithium grease.

  11. Accumulation, transformation and breakdown of DSP toxins from the toxic dinoflagellate Dinophysis acuta in blue mussels, Mytilus edulis.

    PubMed

    Nielsen, Lasse Tor; Hansen, Per Juel; Krock, Bernd; Vismann, Bent

    2016-07-01

    Okadaic acid (OA), dinophysistoxins (DTX) and pectenotoxins (PTX) produced by the dinoflagellates Dinophysis spp. can accumulate in shellfish and cause diarrhetic shellfish poisoning upon human consumption. Shellfish toxicity is a result of algal abundance and toxicity as well as accumulation and depuration kinetics in mussels. We mass-cultured Dinophysis acuta containing OA, DTX-1b and PTX-2 and fed it to the blue mussel, Mytilus edulis under controlled laboratory conditions for a week to study toxin accumulation and transformation. Contents of OA and DTX-1b in mussels increased linearly with incubation time, and the net toxin accumulation was 66% and 71% for OA and DTX-1b, respectively. Large proportions (≈50%) of both these toxins were transformed to fatty acid esters. Most PTX-2 was transformed to PTX-2 seco-acid and net accumulation was initially high, but decreased progressively throughout the experiment, likely due to esterification and loss of detectability. We also quantified depuration during the subsequent four days and found half-life times of 5-6 days for OA and DTX-1b. Measurements of dissolved toxins revealed that depuration was achieved through excreting rather than metabolizing toxins. This is the first study to construct a full mass balance of DSP toxins during both accumulation and depuration, and we demonstrate rapid toxin accumulation in mussels at realistic in situ levels of Dinophysis. Applying the observed accumulation and depuration kinetics, we model mussel toxicity, and demonstrate that a concentration of only 75 Dinophysis cells l(-1) is enough to make 60 mm long mussels exceed the regulatory threshold for OA equivalents.

  12. Transcriptional and Metabolic Analysis of Senescence Induced by Preventing Pollination in Maize1[W][OA

    PubMed Central

    Sekhon, Rajandeep S.; Childs, Kevin L.; Santoro, Nicholas; Foster, Cliff E.; Buell, C. Robin; de Leon, Natalia; Kaeppler, Shawn M.

    2012-01-01

    Transcriptional and metabolic changes were evaluated during senescence induced by preventing pollination in the B73 genotype of maize (Zea mays). Accumulation of free glucose and starch and loss of chlorophyll in leaf was manifested early at 12 d after anthesis (DAA), while global transcriptional and phenotypic changes were evident only at 24 DAA. Internodes exhibited major transcriptomic changes only at 30 DAA. Overlaying expression data onto metabolic pathways revealed involvement of many novel pathways, including those involved in cell wall biosynthesis. To investigate the overlap between induced and natural senescence, transcriptional data from induced senescence in maize was compared with that reported for Arabidopsis (Arabidopsis thaliana) undergoing natural and sugar-induced senescence. Notable similarities with natural senescence in Arabidopsis included up-regulation of senescence-associated genes (SAGs), ethylene and jasmonic acid biosynthetic genes, APETALA2, ethylene-responsive element binding protein, and no apical meristem transcription factors. However, differences from natural senescence were highlighted by unaltered expression of a subset of the SAGs, and cytokinin, abscisic acid, and salicylic acid biosynthesis genes. Key genes up-regulated during sugar-induced senescence in Arabidopsis, including a cysteine protease (SAG12) and three flavonoid biosynthesis genes (PRODUCTION OF ANTHOCYANIN PIGMENT1 (PAP1), PAP2, and LEUCOANTHOCYANIDIN DIOXYGENASE), were also induced, suggesting similarities in senescence induced by pollination prevention and sugar application. Coexpression analysis revealed networks involving known senescence-related genes and novel candidates; 82 of these were shared between leaf and internode networks, highlighting similarities in induced senescence in these tissues. Insights from this study will be valuable in systems biology of senescence in maize and other grasses. PMID:22732243

  13. Contribution of Ethylene Biosynthesis for Resistance to Blast Fungus Infection in Young Rice Plants1[OA

    PubMed Central

    Iwai, Takayoshi; Miyasaka, Atsushi; Seo, Shigemi; Ohashi, Yuko

    2006-01-01

    The role of ethylene (ET) in resistance to infection with blast fungus (Magnaporthe grisea) in rice (Oryza sativa) is poorly understood. To study it, we quantified ET levels after inoculation, using young rice plants at the four-leaf stage of rice cv Nipponbare (wild type) and its isogenic plant (IL7), which contains the Pi-i resistance gene to blast fungus race 003. Small necrotic lesions by hypersensitive reaction (HR) were formed at 42 to 72 h postinoculation (hpi) in resistant IL7 leaves, and whitish expanding lesions at 96 hpi in susceptible wild-type leaves. Notable was the enhanced ET emission at 48 hpi accompanied by increased 1-aminocyclopropane-1-carboxylic acid (ACC) levels and highly elevated ACC oxidase (ACO) activity in IL7 leaves, whereas only an enhanced ACC increase at 96 hpi in wild-type leaves. Among six ACC synthase (ACS) and seven ACO genes found in the rice genome, OsACS2 was transiently expressed at 48 hpi in IL7 and at 96 hpi in wild type, and OsACO7 was expressed at 48 hpi in IL7. Treatment with an inhibitor for ACS, aminooxyacetic acid, suppressed enhanced ET emission at 48 hpi in IL7, resulting in expanding lesions instead of HR lesions. Exogenously supplied ACC compromised the aminooxyacetic acid-induced breakdown of resistance in IL7, and treatment with 1-methylcyclopropene and silver thiosulfate, inhibitors of ET action, did not suppress resistance. These findings suggest the importance of ET biosynthesis and, consequently, the coproduct, cyanide, for HR-accompanied resistance to blast fungus in young rice plants and the contribution of induced OsACS2 and OsACO7 gene expression to it. PMID:17012402

  14. New Insights into the Properties of Pubescent Surfaces: Peach Fruit as a Model1[OA

    PubMed Central

    Fernández, Victoria; Khayet, Mohamed; Montero-Prado, Pablo; Heredia-Guerrero, José Alejandro; Liakopoulos, Georgios; Karabourniotis, George; del Río, Víctor; Domínguez, Eva; Tacchini, Ignacio; Nerín, Cristina; Val, Jesús; Heredia, Antonio

    2011-01-01

    The surface of peach (Prunus persica ‘Calrico’) is covered by a dense indumentum, which may serve various protective purposes. With the aim of relating structure to function, the chemical composition, morphology, and hydrophobicity of the peach skin was assessed as a model for a pubescent plant surface. Distinct physicochemical features were observed for trichomes versus isolated cuticles. Peach cuticles were composed of 53% cutan, 27% waxes, 23% cutin, and 1% hydroxycinnamic acid derivatives (mainly ferulic and p-coumaric acids). Trichomes were covered by a thin cuticular layer containing 15% waxes and 19% cutin and were filled by polysaccharide material (63%) containing hydroxycinnamic acid derivatives and flavonoids. The surface free energy, polarity, and work of adhesion of intact and shaved peach surfaces were calculated from contact angle measurements of water, glycerol, and diiodomethane. The removal of the trichomes from the surface increased polarity from 3.8% (intact surface) to 23.6% and decreased the total surface free energy chiefly due to a decrease on its nonpolar component. The extraction of waxes and the removal of trichomes led to higher fruit dehydration rates. However, trichomes were found to have a higher water sorption capacity as compared with isolated cuticles. The results show that the peach surface is composed of two different materials that establish a polarity gradient: the trichome network, which has a higher surface free energy and a higher dispersive component, and the cuticle underneath, which has a lower surface free energy and higher surface polarity. The significance of the data concerning water-plant surface interactions is discussed within a physiological context. PMID:21685175

  15. Unbiased high-throughput characterization of mussel transcriptomic responses to sublethal concentrations of the biotoxin okadaic acid

    PubMed Central

    Suarez-Ulloa, Victoria; Fernandez-Tajes, Juan; Aguiar-Pulido, Vanessa; Prego-Faraldo, M. Veronica; Florez-Barros, Fernanda; Sexto-Iglesias, Alexia; Mendez, Josefina

    2015-01-01

    Background. Harmful Algal Blooms (HABs) responsible for Diarrhetic Shellfish Poisoning (DSP) represent a major threat for human consumers of shellfish. The biotoxin Okadaic Acid (OA), a well-known phosphatase inhibitor and tumor promoter, is the primary cause of acute DSP intoxications. Although several studies have described the molecular effects of high OA concentrations on sentinel organisms (e.g., bivalve molluscs), the effect of prolonged exposures to low (sublethal) OA concentrations is still unknown. In order to fill this gap, this work combines Next-Generation sequencing and custom-made microarray technologies to develop an unbiased characterization of the transcriptomic response of mussels during early stages of a DSP bloom. Methods. Mussel specimens were exposed to a HAB episode simulating an early stage DSP bloom (200 cells/L of the dinoflagellate Prorocentrum lima for 24 h). The unbiased characterization of the transcriptomic responses triggered by OA was carried out using two complementary methods of cDNA library preparation: normalized and Suppression Subtractive Hybridization (SSH). Libraries were sequenced and read datasets were mapped to Gene Ontology and KEGG databases. A custom-made oligonucleotide microarray was developed based on these data, completing the expression analysis of digestive gland and gill tissues. Results. Our findings show that exposure to sublethal concentrations of OA is enough to induce gene expression modifications in the mussel Mytilus. Transcriptomic analyses revealed an increase in proteasomal activity, molecular transport, cell cycle regulation, energy production and immune activity in mussels. Oppositely, a number of transcripts hypothesized to be responsive to OA (notably the Serine/Threonine phosphatases PP1 and PP2A) failed to show substantial modifications. Both digestive gland and gill tissues responded similarly to OA, although expression modifications were more dramatic in the former, supporting the choice of

  16. Examination, evaluation and repair of laminated wood blades after service on the Mod-OA wind turbine

    NASA Technical Reports Server (NTRS)

    Faddoul, J. R.

    1983-01-01

    Laminated wood blades were designed, fabricated, and installed on a 200-KW wind turbine (Mod-OA). The machine uses a two-blade rotor with a diameter of 38.1 m (125 ft). Each blade weights less than 1361 kg (3000 lb). After operating in the field, two blade sets were returned for inspection. One set had been in Hawaii for 17 months (7844 hr of operation) and the other had been at Block Island, Rhode Island, for 26 months (22 months operating - 7564 hr). The Hawaii set was returned because of one of the studs that holds the blade to the hub had failed. This was found to be caused by a combination of improper installation and inadequate corrosion protection. No other problems were found. The broken stud (along with four others that were badly corroded) was replaced and the blades are now in storage. The Block Island set of blades was returned at the completion of the test program, but one blade was found to have developed a crack in the leading edge along the entire span. This crack was found to be the result of a manufacturing process problem but was not structurally critical. When a load-deflection test was conducted on the cracked blade, the response was identical to that measured before installation. In general, the laminate quality of both blade sets was excellent. No significant internal delamination or structural defects were found in any blade. The stud bonding process requires close tolerance control and adequate corrosion protection, but studs can be removed and replaced without major problems. Moisture content stabilization does not appear to be a problem, and laminated wood blades are satisfactory for long-term operation on Mod-OA wind turbines.

  17. The Coronatine Toxin of Pseudomonas syringae Is a Multifunctional Suppressor of Arabidopsis Defense[W][OA

    PubMed Central

    Geng, Xueqing; Cheng, Jiye; Gangadharan, Anju; Mackey, David

    2012-01-01

    The phytotoxin coronatine (COR) promotes various aspects of Pseudomonas syringae virulence, including invasion through stomata, growth in the apoplast, and induction of disease symptoms. COR is a structural mimic of active jasmonic acid (JA) conjugates. Known activities of COR are mediated through its binding to the F-box–containing JA coreceptor CORONATINE INSENSITIVE1. By analyzing the interaction of P. syringae mutants with Arabidopsis thaliana mutants, we demonstrate that, in the apoplastic space of Arabidopsis, COR is a multifunctional defense suppressor. COR and the critical P. syringae type III effector HopM1 target distinct signaling steps to suppress callose deposition. In addition to its well-documented ability to suppress salicylic acid (SA) signaling, COR suppresses an SA-independent pathway contributing to callose deposition by reducing accumulation of an indole glucosinolate upstream of the activity of the PEN2 myrosinase. COR also suppresses callose deposition and promotes bacterial growth in coi1 mutant plants, indicating that COR may have multiple targets inside plant cells. PMID:23204405

  18. Regulation of Solute Flux through Plasmodesmata in the Root Meristem1[W][OA

    PubMed Central

    Rutschow, Heidi L.; Baskin, Tobias I.; Kramer, Eric M.

    2011-01-01

    Plasmodesmata permit solutes to move between cells nonspecifically and without having to cross a membrane. This symplastic connectivity, while straightforward to observe using fluorescent tracers, has proven difficult to quantify. We use fluorescence recovery after photobleaching, combined with a mathematical model of symplastic diffusion, to assay plasmodesmata-mediated permeability in the Arabidopsis (Arabidopsis thaliana) root meristem in wild-type and transgenic lines, and under selected chemical treatments. The permeability measured for the wild type is nearly 10-times greater than previously reported. Plamodesmal permeability remains constant in seedlings treated with auxin (30 nm indoleacetic acid for 2 and 24 h; 100 nm indoleacetic acid for 2 h); however, permeability is diminished in two lines previously reported to have impaired plasmodesmal function as well as in wild-type seedlings treated for 24 h with 0.6 mm tryptophan. Moreover, plasmodesmal permeability is strongly altered by applied hydrogen peroxide within 2 h of treatment, being approximately doubled at a low concentration (0.6 mm) and nearly eliminated at a higher one (6 mm). These results reveal that the plasmodesmata in the root meristem carry a substantial flux of small molecules and that this flux is subject to rapid regulation. PMID:21325566

  19. Unraveling the confusion behind hyaluronic acid efficacy in the treatment of symptomatic knee osteoarthritis

    PubMed Central

    Miller, Larry E; Altman, Roy D; McIntyre, Louis F

    2016-01-01

    Hyaluronic acid (HA) is a commonly prescribed treatment for knee pain resulting from osteoarthritis (OA). Although numerous HA products have been approved for use by the US Food and Drug Administration, the efficacy of HA injections for knee OA remains disputed with meta-analyses and societal clinical guidelines drawing disparate conclusions. The American Academy of Orthopaedic Surgeons (AAOS) recently published a best-evidence systematic review and concluded that available data did not support the routine use of HA for knee OA. The purpose of the current article is to highlight issues that confound interpretation of meta-analyses on HA for knee OA, to provide realistic estimates of the true efficacy of HA injections in knee OA, and to provide commentary on the methods and conclusions from the AAOS systematic review. In general, the clinical benefit of HA is underestimated using conventional meta-analytic techniques. When accounting for differential control group effects in HA studies, it can be reasonably concluded that HA injections may be beneficial to an appreciable number of patients with knee OA. In addition, the systematic review methodology used by AAOS was questionable due to exclusion of numerous relevant studies and inclusion of studies that used HAs not approved for use in the US, both of which underestimated the true efficacy of HA injections. Overall, the efficacy of HA injections for knee OA is likely better than previously reported. Future clinical trials and meta-analyses should account for differential control group effects in order to avoid the continued confusion surrounding HA injection efficacy. PMID:27382328

  20. Oleanolic Acid Controls Allergic and Inflammatory Responses in Experimental Allergic Conjunctivitis

    PubMed Central

    Martínez-García, Carmen; Martín, Rubén; Gallego-Muñoz, Patricia; Hernández, Marita; Nieto, María L.

    2014-01-01

    Pollen is the most common aeroallergen to cause seasonal conjunctivitis. The result of allergen exposure is a strong Th2-mediated response along with conjunctival mast cell degranulation and eosinophilic infiltration. Oleanolic acid (OA) is natural a triterpene that displays strong anti-inflammatory and immunomodulatory properties being an active anti-allergic molecule on hypersensitivity reaction models. However, its effect on inflammatory ocular disorders including conjunctivits, has not yet been addressed. Hence, using a Ragweed pollen (RWP)-specific allergic conjunctivitis (EAC) mouse model we study here whether OA could modify responses associated to allergic processes. We found that OA treatment restricted mast cell degranulation and infiltration of eosinophils in conjunctival tissue and decreased allergen-specific Igs levels in EAC mice. Th2-type cytokines, secreted phospholipase A2 type-IIA (sPLA2-IIA), and chemokines levels were also significantly diminished in the conjunctiva and serum of OA-treated EAC mice. Moreover, OA treatment also suppressed RWP-specific T-cell proliferation. In vitro studies, on relevant cells of the allergic process, revealed that OA reduced the proliferative and migratory response, as well as the synthesis of proinflammatory mediators on EoL-1 eosinophils and RBL-2H3 mast cells exposed to allergic and/or crucial inflammatory stimuli such as RWP, sPLA2-IIA or eotaxin. Taken together, these findings demonstrate the beneficial activity of OA in ocular allergic processes and may provide a new intervention strategy and potential therapy for allergic diseases. PMID:24699261

  1. Comparison of Oil Content and Fatty Acid Profile of Ten New Camellia oleifera Cultivars

    PubMed Central

    Yang, Chunying; Liu, Xueming; Chen, Zhiyi; Lin, Yaosheng; Wang, Siyuan

    2016-01-01

    The oil contents and fatty acid (FA) compositions of ten new and one wild Camellia oleifera varieties were investigated. Oil contents in camellia seeds from new C. oleifera varied with cultivars from 41.92% to 53.30% and were affected by cultivation place. Average oil content (47.83%) of dry seeds from all ten new cultivars was almost the same as that of wild common C. oleifera seeds (47.06%). New C. oleifera cultivars contained similar FA compositions which included palmitic acid (C16:0, PA), palmitoleic acid (C16:1), stearic acid (C18:0, SA), oleic acid (C18:1, OA), linoleic acid (C18:2, LA), linolenic acid (C18:3), eicosenoic acid (C20:1), and tetracosenoic acid (C24:1). Predominant FAs in mature seeds were OA (75.78%~81.39%), LA (4.85%~10.79%), PA (7.68%~10.01%), and SA (1.46%~2.97%) and OA had the least coefficient of variation among different new cultivars. Average ratio of single FA of ten artificial C. oleifera cultivars was consistent with that of wild common C. oleifera. All cultivars contained the same ratios of saturated FA (SFA) and unsaturated FA (USFA). Oil contents and FA profiles of new cultivars were not significantly affected by breeding and selection. PMID:26942012

  2. Efficacy of oxalic acid to reduce Salmonella spp. at various states of poultry processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The microbiological safety of fresh eviscerated poultry has continued to be a major concern of the consumer and the poultry industry due to the frequent foodborne illnesses caused by Salmonella spp. Oxalic acid (OA) was evaluated as an antimicrobial treatment at equivalent dip, scalding, and chillin...

  3. An overview of the modulatory effects of oleic acid in health and disease.

    PubMed

    Sales-Campos, Helioswilton; Souza, Patricía Reis de; Peghini, Bethânea Crema; da Silva, João Santana; Cardoso, Cristina Ribeiro

    2013-02-01

    Evidences in the last years have showed the effects of oleic acid (OA) in human health and disease. Olive oil, rich in oleic acid, is supposed to present modulatory effects in a wide physiological functions, while some studies also suggest a beneficial effect on cancer, autoimmune and inflammatory diseases, besides its ability to facilitate wound healing. Although the OA role in immune responses are still controversial, the administration of olive oil containing diets may improve the immune response associated to a more successful elimination of pathogens such as bacteria and fungi, by interfering in many components of this system such as macrophages, lymphocytes and neutrophils. Then, novel putative therapies for inflammatory and infectious diseases could be developed based on the characteristics presented by unsaturated fatty acids like OA. Finally, the purpose of this work was to review some of the modulatory effects of OA on inflammatory diseases and health, aiming at high lightening its potential role on the future establishment of novel therapeutic approaches for infections, inflammatory, immune, cardiovascular diseases or skin repair based on this fatty acid mainly found in the Mediterranean diet.

  4. Reduced Carbohydrate Availability Enhances the Susceptibility of Arabidopsis toward Colletotrichum higginsianum1[W][OA

    PubMed Central

    Engelsdorf, Timo; Horst, Robin J.; Pröls, Reinhard; Pröschel, Marlene; Dietz, Franziska; Hückelhoven, Ralph; Voll, Lars M.

    2013-01-01

    Colletotrichum higginsianum is a hemibiotrophic ascomycete fungus that is adapted to Arabidopsis (Arabidopsis thaliana). After breaching the host surface, the fungus establishes an initial biotrophic phase in the penetrated epidermis cell, before necrotrophic growth is initiated upon further host colonization. We observed that partitioning of major leaf carbohydrates was shifted in favor of sucrose and at the expense of starch during necrotrophic fungal growth. Arabidopsis mutants with impaired starch turnover were more susceptible toward C. higginsianum infection, exhibiting a strong negative correlation between diurnal carbohydrate accumulation and fungal proliferation for the tested genotypes. By altering the length of the light phase and employing additional genotypes impaired in nocturnal carbon mobilization, we revealed that reduced availability of carbon enhances susceptibility in the investigated pathosystem. Systematic starvation experiments resulted in two important findings. First, we showed that carbohydrate supply by the host is dispensable during biotrophic growth of C. higginsianum, while carbon deficiency was most harmful to the host during the necrotrophic colonization phase. Compared with the wild type, the increases in the total salicylic acid pool and camalexin accumulation were reduced in starch-free mutants at late interaction stages, while an increased ratio of free to total salicylic acid did not convey elevated pathogenesis-related gene expression in starch-free mutants. These observations suggest that reduced carbon availability dampens induced defense responses. In contrast, starch-free mutants were more resistant toward the fungal biotroph Erysiphe cruciferarum, indicating that reduced carbohydrate availability influences susceptibility differently in the interaction with the investigated hemibiotrophic and biotrophic fungal pathogens. PMID:23487433

  5. Role for Apyrases in Polar Auxin Transport in Arabidopsis1[C][W][OA

    PubMed Central

    Liu, Xing; Wu, Jian; Clark, Greg; Lundy, Stacey; Lim, Minhui; Arnold, David; Chan, Jing; Tang, Wenqiang; Muday, Gloria K.; Gardner, Gary; Roux, Stanley J.

    2012-01-01

    Recent evidence indicates that extracellular nucleotides regulate plant growth. Exogenous ATP has been shown to block auxin transport and gravitropic growth in primary roots of Arabidopsis (Arabidopsis thaliana). Cells limit the concentration of extracellular ATP in part through the activity of ectoapyrases (ectonucleoside triphosphate diphosphohydrolases), and two nearly identical Arabidopsis apyrases, APY1 and APY2, appear to share this function. These findings, plus the fact that suppression of APY1 and APY2 blocks growth in Arabidopsis, suggested that the expression of these apyrases could influence auxin transport. This report tests that hypothesis. The polar movement of [3H]indole-3-acetic acid in both hypocotyl sections and primary roots of Arabidopsis seedlings was measured. In both tissues, polar auxin transport was significantly reduced in apy2 null mutants when they were induced by estradiol to suppress the expression of APY1 by RNA interference. In the hypocotyl assays, the basal halves of APY-suppressed hypocotyls contained considerably lower free indole-3-acetic acid levels when compared with wild-type plants, and disrupted auxin transport in the APY-suppressed roots was reflected by their significant morphological abnormalities. When a green fluorescent protein fluorescence signal encoded by a DR5:green fluorescent protein construct was measured in primary roots whose apyrase expression was suppressed either genetically or chemically, the roots showed no signal asymmetry following gravistimulation, and both their growth and gravitropic curvature were inhibited. Chemicals that suppress apyrase activity also inhibit gravitropic curvature and, to a lesser extent, growth. Taken together, these results indicate that a critical step connecting apyrase suppression to growth suppression is the inhibition of polar auxin transport. PMID:23071251

  6. Toward the Storage Metabolome: Profiling the Barley Vacuole1[W][OA

    PubMed Central

    Tohge, Takayuki; Ramos, Magali Schnell; Nunes-Nesi, Adriano; Mutwil, Marek; Giavalisco, Patrick; Steinhauser, Dirk; Schellenberg, Maja; Willmitzer, Lothar; Persson, Staffan; Martinoia, Enrico; Fernie, Alisdair R.

    2011-01-01

    While recent years have witnessed dramatic advances in our capacity to identify and quantify an ever-increasing number of plant metabolites, our understanding of how metabolism is spatially regulated is still far from complete. In an attempt to partially address this question, we studied the storage metabolome of the barley (Hordeum vulgare) vacuole. For this purpose, we used highly purified vacuoles isolated by silicon oil centrifugation and compared their metabolome with that found in the mesophyll protoplast from which they were derived. Using a combination of gas chromatography-mass spectrometry and Fourier transform-mass spectrometry, we were able to detect 59 (primary) metabolites for which we know the exact chemical structure and a further 200 (secondary) metabolites for which we have strong predicted chemical formulae. Taken together, these metabolites comprise amino acids, organic acids, sugars, sugar alcohols, shikimate pathway intermediates, vitamins, phenylpropanoids, and flavonoids. Of the 259 putative metabolites, some 12 were found exclusively in the vacuole and 34 were found exclusively in the protoplast, while 213 were common in both samples. When analyzed on a quantitative basis, however, there is even more variance, with more than 60 of these compounds being present above the detection limit of our protocols. The combined data were also analyzed with respect to the tonoplast proteome in an attempt to infer specificities of the transporter proteins embedded in this membrane. Following comparison with recent observations made using nonaqueous fractionation of Arabidopsis (Arabidopsis thaliana), we discuss these data in the context of current models of metabolic compartmentation in plants. PMID:21949213

  7. Nitro-oleic acid inhibits firing and activates TRPV1- and TRPA1-mediated inward currents in dorsal root ganglion neurons from adult male rats.

    PubMed

    Sculptoreanu, A; Kullmann, F A; Artim, D E; Bazley, F A; Schopfer, F; Woodcock, S; Freeman, B A; de Groat, W C

    2010-06-01

    Nitro-oleic acid (OA-NO(2)), an electrophilic fatty acid by-product of nitric oxide and nitrite reactions, is present in normal and inflamed mammalian tissues at up to micromolar concentrations and exhibits anti-inflammatory signaling actions. The effects of OA-NO(2) on cultured dorsal root ganglion (DRG) neurons were examined using fura-2 Ca(2+) imaging and patch clamping. OA-NO(2) (3.5-35 microM) elicited Ca(2+) transients in 20 to 40% of DRG neurons, the majority (60-80%) of which also responded to allyl isothiocyanate (AITC; 1-50 microM), a TRPA1 agonist, and to capsaicin (CAPS; 0.5 microM), a TRPV1 agonist. The OA-NO(2)-evoked Ca(2+) transients were reduced by the TRPA1 antagonist 2-(1,3-dimethyl-2,6-dioxo-1,2,3,6-tetrahydro-7H-purin-7-yl)-N-(4-isopropylphenyl) acetamide (HC-030031; 5-50 microM) and the TRPV1 antagonist capsazepine (10 microM). Patch-clamp recording revealed that OA-NO(2) depolarized and induced inward currents in 62% of neurons. The effects of OA-NO(2) were elicited by concentrations >or=5 nM and were blocked by 10 mM dithiothreitol. Concentrations of OA-NO(2) >or=5 nM reduced action potential (AP) overshoot, increased AP duration, inhibited firing induced by depolarizing current pulses, and inhibited Na(+) currents. The effects of OA-NO(2) were not prevented or reversed by the NO-scavenger carboxy-2-phenyl-4,4,5,5-tetramethylimidazolineoxyl-1-oxyl-3-oxide. A large percentage (46-57%) of OA-NO(2)-responsive neurons also responded to CAPS (0.5 microM) or AITC (0.5 microM). OA-NO(2) currents were reduced by TRPV1 (diarylpiperazine; 5 microM) or TRPA1 (HC-030031; 5 microM) antagonists. These data reveal that endogenous OA-NO(2) generated at sites of inflammation may initially activate transient receptor potential channels on nociceptive afferent nerves, contributing to the initiation of afferent nerve activity, and later suppresses afferent firing.

  8. Fatty Acid Ethyl Esters Are Less Toxic Than Their Parent Fatty Acids Generated during Acute Pancreatitis

    PubMed Central

    Patel, Krutika; Durgampudi, Chandra; Noel, Pawan; Trivedi, Ram N.; de Oliveira, Cristiane; Singh, Vijay P.

    2017-01-01

    Although ethanol causes acute pancreatitis (AP) and lipolytic fatty acid (FA) generation worsens AP, the contribution of ethanol metabolites of FAs, ie, FA ethyl esters (FAEEs), to AP outcomes is unclear. Previously, pancreata of dying alcoholics and pancreatic necrosis in severe AP, respectively, showed high FAEEs and FAs, with oleic acid (OA) and its ethyl esters being the most abundant. We thus compared the toxicities of FAEEs and their parent FAs in severe AP. Pancreatic acini and peripheral blood mononuclear cells were exposed to FAs or FAEEs in vitro. The triglyceride of OA (i.e., glyceryl tri-oleate) or OAEE was injected into the pancreatic ducts of rats, and local and systemic severities were studied. Unsaturated FAs at equimolar concentrations to FAEEs induced a larger increase in cytosolic calcium, mitochondrial depolarization, and necro-apoptotic cell death. Glyceryl tri-oleate but not OAEE resulted in 70% mortality with increased serum OA, a severe inflammatory response, worse pancreatic necrosis, and multisystem organ failure. Our data show that FAs are more likely to worsen AP than FAEEs. Our observations correlate well with the high pancreatic FAEE concentrations in alcoholics without pancreatitis and high FA concentrations in pancreatic necrosis. Thus, conversion of FAs to FAEE may ameliorate AP in alcoholics. PMID:26878214

  9. The ocular albinism type 1 (OA1) GPCR is ubiquitinated and its traffic requires endosomal sorting complex responsible for transport (ESCRT) function

    PubMed Central

    Giordano, Francesca; Simoes, Sabrina; Raposo, Graça

    2011-01-01

    The function of signaling receptors is tightly controlled by their intracellular trafficking. One major regulatory mechanism within the endo-lysosomal system required for receptor localization and down-regulation is protein modification by ubiquitination and downstream interactions with the endosomal sorting complex responsible for transport (ESCRT) machinery. Whether and how these mechanisms operate to regulate endosomal sorting of mammalian G protein-coupled receptors (GPCRs) remains unclear. Here, we explore the involvement of ubiquitin and ESCRTs in the trafficking of OA1, a pigment cell-specific GPCR, target of mutations in Ocular Albinism type 1, which localizes intracellularly to melanosomes to regulate their biogenesis. Using biochemical and morphological methods in combination with overexpression and inactivation approaches we show that OA1 is ubiquitinated and that its intracellular sorting and down-regulation requires functional ESCRT components. Depletion or overexpression of subunits of ESCRT-0, -I, and -III markedly inhibits OA1 degradation with concomitant retention within the modified endosomal system. Our data further show that OA1 ubiquitination is uniquely required for targeting to the intralumenal vesicles of multivesicular endosomes, thereby regulating the balance between down-regulation and delivery to melanosomes. This study highlights the role of ubiquitination and the ESCRT machinery in the intracellular trafficking of mammalian GPCRs and has implications for the physiopathology of ocular albinism type 1. PMID:21730137

  10. The ocular albinism type 1 (OA1) GPCR is ubiquitinated and its traffic requires endosomal sorting complex responsible for transport (ESCRT) function.

    PubMed

    Giordano, Francesca; Simoes, Sabrina; Raposo, Graça

    2011-07-19

    The function of signaling receptors is tightly controlled by their intracellular trafficking. One major regulatory mechanism within the endo-lysosomal system required for receptor localization and down-regulation is protein modification by ubiquitination and downstream interactions with the endosomal sorting complex responsible for transport (ESCRT) machinery. Whether and how these mechanisms operate to regulate endosomal sorting of mammalian G protein-coupled receptors (GPCRs) remains unclear. Here, we explore the involvement of ubiquitin and ESCRTs in the trafficking of OA1, a pigment cell-specific GPCR, target of mutations in Ocular Albinism type 1, which localizes intracellularly to melanosomes to regulate their biogenesis. Using biochemical and morphological methods in combination with overexpression and inactivation approaches we show that OA1 is ubiquitinated and that its intracellular sorting and down-regulation requires functional ESCRT components. Depletion or overexpression of subunits of ESCRT-0, -I, and -III markedly inhibits OA1 degradation with concomitant retention within the modified endosomal system. Our data further show that OA1 ubiquitination is uniquely required for targeting to the intralumenal vesicles of multivesicular endosomes, thereby regulating the balance between down-regulation and delivery to melanosomes. This study highlights the role of ubiquitination and the ESCRT machinery in the intracellular trafficking of mammalian GPCRs and has implications for the physiopathology of ocular albinism type 1.

  11. A genome-wide association study suggests that a locus within the ataxin 2 binding protein 1 gene is associated with hand osteoarthritis: the Treat-OA consortium

    PubMed Central

    Zhai, G; van Meurs, J B J; Livshits, G; Meulenbelt, I; Valdes, A M; Soranzo, N; Hart, D; Zhang, F; Kato, B S; Richards, J B; Williams, F M K; Inouye, M; Kloppenburg, M; Deloukas, P; Slagboom, E; Uitterlinden, A; Spector, T D

    2009-01-01

    To identify the susceptibility gene in hand osteoarthritis (OA) the authors used a two-stage approach genome-wide association study using two discovery samples (the TwinsUK cohort and the Rotterdam discovery subset; a total of 1804 subjects) and four replication samples (the Chingford Study, the Chuvasha Skeletal Aging Study, the Rotterdam replication subset and the Genetics, Arthrosis, and Progression (GARP) Study; a total of 3266 people). Five single-nucleotide polymorphisms (SNPs) had a likelihood of association with hand OA in the discovery stage and one of them (rs716508), was successfully confirmed in the replication stage (meta-analysis p = 1.81×10−5). The C allele conferred a reduced risk of 33% to 41% using a case–control definition. The SNP is located in intron 1 of the A2BP1 gene. This study also found that the same allele of the SNP significantly reduced bone density at both the hip and spine (p<0.01), suggesting the potential mechanism of the gene in hand OA might be via effects on subchondral bone. The authors' findings provide a potential new insight into genetic mechanisms in the development of hand OA. PMID:19508968

  12. Research of fluorescent spectra of oleic acid-stabilized ZnSe nanocrystals based on UV light modification

    NASA Astrophysics Data System (ADS)

    Hao, Licai; Bai, Zhongchen; Huang, Zhaoliang; Liao, Sha; Zhang, Zhengping

    2016-11-01

    The non-aqueous synthesized and post-preparative treatment of oleic acid (OA)-stabilized ZnSe nanocrystals were studied systematically. ZnSe nanocrystals were successfully synthesized via paraffin liquid and oleic acid system by using OA as stabilizer. Synthesized nanocrystals were characterized by means of absorption and fluorescent spectra, Fourier transform infrared spectrometer, transmission electron microscopy and selected area electron diffraction. Furthermore, solutions of ZnSe nanocrystals were illuminated with UV light. The experimental results showed that the fluorescent peak was red-shifted from 445 to 510 nm. The results suggested that, when the solution under illumination, OA was removed from the surface of ZnSe nanocrystals and the surface of ZnSe nanocrystals was oxidized to ZnO nanocrystals. ZnSe/ZnO core/shell nanocrystals were formed when the solution of ZnSe nanocrystals illuminated with UV light.

  13. Is Protein Phosphatase Inhibition Responsible for the Toxic Effects of Okadaic Acid in Animals?

    PubMed Central

    Munday, Rex

    2013-01-01

    Okadaic acid (OA) and its derivatives, which are produced by dinoflagellates of the genera Prorocentrum and Dinophysis, are responsible for diarrhetic shellfish poisoning in humans. In laboratory animals, these toxins cause epithelial damage and fluid accumulation in the gastrointestinal tract, and at high doses, they cause death. These substances have also been shown to be tumour promoters, and when injected into the brains of rodents, OA induces neuronal damage reminiscent of that seen in Alzheimer’s disease. OA and certain of its derivatives are potent inhibitors of protein phosphatases, which play many roles in cellular metabolism. In 1990, it was suggested that inhibition of these enzymes was responsible for the diarrhetic effect of these toxins. It is now repeatedly stated in the literature that protein phosphatase inhibition is not only responsible for the intestinal effects of OA and derivatives, but also for their acute toxic effects, their tumour promoting activity and their neuronal toxicity. In the present review, the evidence for the involvement of protein phosphatase inhibition in the induction of the toxic effects of OA and its derivatives is examined, with the conclusion that the mechanism of toxicity of these substances requires re-evaluation. PMID:23381142

  14. Marine Toxin Okadaic Acid Affects the Immune Function of Bay Scallop (Argopecten irradians).

    PubMed

    Chi, Cheng; Giri, Sib Sankar; Jun, Jin Woo; Kim, Hyoun Joong; Yun, Saekil; Kim, Sang Guen; Park, Se Chang

    2016-08-24

    Okadaic acid (OA) is produced by dinoflagellates during harmful algal blooms and is a diarrhetic shellfish poisoning toxin. This toxin is particularly problematic for bivalves that are cultured for human consumption. This study aimed to reveal the effects of exposure to OA on the immune responses of bay scallop, Argopecten irradians. Various immunological parameters were assessed (total hemocyte counts (THC), reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH), lactate dehydrogenase (LDH), and nitric oxide (NO) in the hemolymph of scallops at 3, 6, 12, 24, and 48 h post-exposure (hpe) to different concentrations of OA (50, 100, and 500 nM). Moreover, the expression of immune-system-related genes (CLT-6, FREP, HSP90, MT, and Cu/ZnSOD) was also measured. Results showed that ROS, MDA, and NO levels and LDH activity were enhanced after exposure to different concentrations of OA; however, both THC and GSH decreased between 24-48 hpe. The expression of immune-system-related genes was also assessed at different time points during the exposure period. Overall, our results suggest that exposure to OA had negative effects on immune system function, increased oxygenic stress, and disrupted metabolism of bay scallops.

  15. Oleanolic Acid Induces the Type III Secretion System of Ralstonia solanacearum

    PubMed Central

    Wu, Dousheng; Ding, Wei; Zhang, Yong; Liu, Xuejiao; Yang, Liang

    2015-01-01

    Ralstonia solanacearum, the causal agent of bacterial wilt, can naturally infect a wide range of host plants. The type III secretion system (T3SS) is a major virulence determinant in this bacterium. Studies have shown that plant-derived compounds are able to inhibit or induce the T3SS in some plant pathogenic bacteria, though no specific T3SS inhibitor or inducer has yet been identified in R. solanacearum. In this study, a total of 50 different compounds were screened and almost half of them (22 of 50) significantly inhibited or induced the T3SS expression of R. solanacearum. Based on the strong induction activity on T3SS, the T3SS inducer oleanolic acid (OA) was chosen for further study. We found that OA induced the expression of T3SS through the HrpG-HrpB pathway. Some type III effector genes were induced in T3SS inducing medium supplemented with OA. In addition, OA targeted only the T3SS and did not affect other virulence determinants. Finally, we observed that induction of T3SS by OA accelerated disease progress on tobacco. Overall our results suggest that plant-derived compounds are an abundant source of R. solanacearum T3SS regulators, which could prove useful as tools to interrogate the regulation of this key virulence pathway. PMID:26732647

  16. Docosahexenoic acid treatment ameliorates cartilage degeneration via a p38 MAPK-dependent mechanism

    PubMed Central

    WANG, ZHENZHONG; GUO, AI; MA, LIFENG; YU, HAOMIAO; ZHANG, LIANG; MENG, HAI; CUI, YINPENG; YU, FEI; YANG, BO

    2016-01-01

    Osteoarthritis (OA) is a common chronic inflammatory disease, characterized by cartilage degradation. The aberrant expression of matrix metalloproteinase-13 (MMP-13) plays a vital role in the pathogenesis of OA. The anti-inflammatory property of docosahexenoic acid (DHA) was previously revealed and showed that DHA retards the progress of many types of inflammatory disease. To evaluate the prophylactic function of DHA in OA, the effect of DHA on cartilage degeneration was assessed in interleukin-1β (IL-1β) stimulated human chondrosarcoma SW1353 cells or a rat model of adjuvant-induced arthritis (AIA). The safe concentration range (0–50 µg/ml in vitro) of DHA was determined by flow cytometry and MTT assay. The inhibitory effects of DHA on MMP-13 mRNA and protein expression were confirmed by RT-qPCR, ELISA and western blotting. Furthermore, findings of an in vivo study showed that DHA can increase the thickness of articular cartilage and decrease MMP-13 expression in cartilage matrix in a rat AIA model. We also revealed the mechanism by which DHA ameliorates cartilage degeneration from OA. The DHA-mediated inhibition of MMP-13 expression was partially attributed to the inactivation of the p38 mitogen-activated protein kinases pathway by suppressing p-p38 in IL-1β-stimulated SW1353 cells and a rat AIA model. Our findings suggested that DHA is a promising therapeutic agent that may be used for the prevention and treatment of OA. PMID:27082436

  17. Identification of okadaic acid-induced phosphorylation events by a mass spectrometry approach

    SciTech Connect

    Hill, Jennifer J. . E-mail: Jennifer.Hill@nrc.gc.ca; Callaghan, Deborah A.; Ding Wen; Kelly, John F.; Chakravarthy, Balu R.

    2006-04-14

    Okadaic acid (OA) is a widely used small-molecule phosphatase inhibitor that is thought to selectively inhibit protein phosphatase 2A (PP2A). Multiple studies have demonstrated that PP2A activity is compromised in Brains of Alzheimer's disease patients. Thus, we set out to determine changes in phosphorylation that occur upon OA treatment of neuronal cells. Utilizing isotope-coded affinity tags and mass spectrometry analysis, we determined the relative abundance of proteins in a phosphoprotein enriched fraction from control and OA-treated primary cortical neurons. We identified many proteins whose phosphorylation state is regulated by OA, including glycogen synthase kinase 3{beta}, collapsin-response mediator proteins (DRP-2, DPYSL-5, and CRMP-4), and the B subunit of PP2A itself. Most interestingly, we have found that complexin 2, an important regulator of neurotransmitter release and synaptic plasticity, is phosphorylated at serine 93 upon OA treatment of neurons. This is First report of a phosphorylation site on complexin 2.

  18. Okadaic acid-induced inhibition of B-50 dephosphorylation by presynaptic membrane-associated protein phosphatases.

    PubMed

    Han, Y F; Dokas, L A

    1991-10-01

    The neuronal tissue-specific protein kinase C (PKC) substrate B-50 can be dephosphorylated by endogenous protein phosphatases (PPs) in synaptic plasma membranes (SPMs). The present study characterizes membrane-associated B-50 phosphatase activity by using okadaic acid (OA) and purified 32P-labeled substrates. At a low concentration of [gamma-32P]ATP, PKC-mediated [32P]phosphate incorporation into B-50 in SPMs reached a maximal value at 30 s, followed by dephosphorylation. OA, added 30 s after the initiation of phosphorylation, partially prevented the dephosphorylation of B-50 at 2 nM, a dose that inhibits PP-2A. At the higher concentration of 1 microM, a dose of OA that inhibits PP-1 as well as PP-2A, a nearly complete blockade of B-50 dephosphorylation was seen. Heat-stable PP inhibitor-2 (I-2) also inhibited dephosphorylation of B-50. The effects of OA and I-2 on B-50 phosphatase activity were additive. Endogenous PP-1- and PP-2A-like activities in SPMs were also demonstrated by their capabilities of dephosphorylating [32P]phosphorylase a and [32P]casein. With these exogenous substrates, sensitivities of the membrane-bound phosphatases to OA and I-2 were found to be similar to those of purified forms of these enzymes. These results indicate that PP-1- and PP-2A-like enzymes are the major B-50 phosphatases in SPMs.

  19. Biochemical Basis of the Antidiabetic Activity of Oleanolic Acid and Related Pentacyclic Triterpenes

    PubMed Central

    Castellano, Jose M.; Guinda, Angeles; Delgado, Teresa; Rada, Mirela; Cayuela, Jose A.

    2013-01-01

    Oleanolic acid (OA), a natural component of many plant food and medicinal herbs, is endowed with a wide range of pharmacological properties whose therapeutic potential has only partly been exploited until now. Throughout complex and multifactorial mechanisms, OA exerts beneficial effects against diabetes and metabolic syndrome. It improves insulin response, preserves functionality and survival of β-cells, and protects against diabetes complications. OA may directly modulate enzymes connected to insulin biosynthesis, secretion, and signaling. However, its major contributions appear to be derived from the interaction with important transduction pathways, and many of its effects are consistently related to activation of the transcription factor Nrf2. Doing that, OA induces the expression of antioxidant enzymes and phase II response genes, blocks NF-κB, and represses the polyol pathway, AGEs production, and hyperlipidemia. The management of type 2 diabetes requires an integrated approach, which includes the early intervention to prevent or delay the disease progression, and the use of therapies to control glycemia and lipidemia in its late stages. In this sense, the use of functional foods or drugs containing OA is, undoubtedly, an interesting path. PMID:23704520

  20. Doxorubicin hydrochloride-oleic acid conjugate loaded nanostructured lipid carriers for tumor specific drug release.

    PubMed

    Zhao, Shuangni; Minh, Le Van; Li, Na; Garamus, Vasil M; Handge, Ulrich A; Liu, Jianwen; Zhang, Rongguang; Willumeit-Römer, Regine; Zou, Aihua

    2016-09-01

    The hydrophilic drug Doxorubicin hydrochloride (DOX) paired with oleic acid (OA) was successfully incorporated into nanostructured lipid carriers (NLCs) by a high-pressure homogenization (HPH) method. Drug nanovehicles with proper physico-chemical characteristics (less than 200nm with narrow size distribution, spherical shape, layered internal organization, and negative electrical charge) were prepared and characterized by dynamic light scattering, zeta potential measurements, transmission electron microscopy, small-angle X-ray scattering and differential scanning calorimetry. The drug loading and entrapment efficiency of DOX-OA/NLCs were 4.09% and 97.80%, respectively. A pH-dependent DOX release from DOX-OA/NLCs, i.e., fast at pH 3.8 and 5.7 and sustained at pH 7.4, was obtained. A cytotoxicity assay showed that DOX-OA/NLCs had comparable cytotoxicity to pure DOX and were favorably taken up by HCT 116 cells. The intracellular distribution of DOX was also studied using a confocal laser scanning microscope. All of these results demonstrated that DOX-OA/NLCs could be a promising drug delivery system with tumor-specific DOX release for cancer treatment.

  1. Sulfated glycosaminoglycans and glucosamine may synergize in promoting synovial hyaluronic acid synthesis.

    PubMed

    McCarty, M F; Russell, A L; Seed, M P

    2000-05-01

    High-molecular-weight hyaluronic acid (HA) produced by the synovium may function physiologically to aid preservation of cartilage structure and prevent arthritic pain; both the size and concentration of HA in synovial fluid are diminished in osteoarthritis (OA). Glucosamine therapy for OA can be expected to increase synovial HA production by providing rate-limiting substrate. In addition, certain sulfated glycosaminoglycans and polysaccharides - including chondroitin sulfate (CS), dermatan sulfate, and pentosan polysulfate - stimulate synovial HA production, apparently owing to a hormone-like effect triggered by the binding of these polymers to membrane proteins of synovial cells. Surprisingly, a significant proportion of orally administered CS is absorbed as intact polymers - apparently by pinocytosis. These considerations may rationalize clinical studies concluding that oral CS provides slow-onset but durable pain relief and functional improvement in OA. The possibility that oral glucosamine and CS may interact in a complementary or synergistic fashion to improve synovial fluid HA content in OA should be assessed in clinical studies, and the potential of adjunctive CS administration to improve the clinical response achievable with optimal intakes of glucosamine should likewise be evaluated. In light of the fact that the synovium virtually functions as a 'placenta' for cartilage, focusing on synovium as the target for therapeutic intervention in OA may be a rational strategy.

  2. Comparing oxalic acid and sucrocide treatments for Varroa destructor (Acari: Varroidae) control under desert conditions.

    PubMed

    Sammataro, D; Finley, J; Underwood, R

    2008-08-01

    The effectiveness of oxalic acid (OA) and Sucrocide (S) (AVA Chemical Ventures, L.L.C., Portsmouth, NH) in reducing populations of the varroa mite Varroa destructor Anderson & Trueman (Acari: Varroidae) in honey bee, Apis mellifera L. (Hymenoptera: Apidae) colonies was measured under the desert conditions of Arizona, USA. OA and S were applied three times 7 d apart. A 3.2% solution of OA was applied in sugar syrup via a large volume syringe, trickling 5 ml per space between frames in the colony. S was applied at a concentration of 0.625% (mixed with water), according to the label directions, using a compressed air Chapin sprayer at 20 psi to apply 59 ml per frame space. Varroa mites, collected on a sticky board before, during, and after the treatments, were counted to assess the effectiveness of the treatments. This study showed that a desert climate zone did not confer any positive or negative results on the acaricidal properties of OA. Even with brood present in colonies, significant varroa mite mortality occurred in the OA colonies. In contrast, we found that Sucrocide was not effective as a mite control technique. Despite its ability to increase mite mortality in the short-term, varroa mite populations measured posttreatment were not affected any more by Sucrocide than by no treatment at all.

  3. SOCS-1 and SOCS-3 inhibit IFN-alpha-induced expression of the antiviral proteins 2,5-OAS and MxA.

    PubMed

    Vlotides, George; Sörensen, Astrid S; Kopp, Florian; Zitzmann, Kathrin; Cengic, Neziha; Brand, Stephan; Zachoval, Reinhart; Auernhammer, Christoph J

    2004-07-30

    Although the use of IFN-alpha in combination with ribavirin has improved the treatment efficacy of chronic hepatitis C virus (HCV) infection, 20-50% of patients still fail to eradicate the virus depending on the HCV genotype. Recently, overexpression of HCV core protein has been shown to inhibit IFN signaling and induce SOCS-3 expression. Aim of this study was to examine the putative role of SOCS proteins in IFN resistance. By Western blot analysis, a 4-fold induction of STAT-1/3 phosphorylation by IFN-alpha was observed in mock-transfected HepG2 clones. In contrast, IFN-induced STAT-1/3 phosphorylation was considerably downregulated by SOCS-1/3 overexpression. In mock-transfected cells, IFN-alpha induced 2',5'-OAS and myxovirus resistance A (MxA) promoter activity 40- to 80-fold and 10- to 35-fold, respectively, and this effect was abrogated in SOCS-1/3 overexpressing cells. As detected by Northern blot technique, IFN-alpha potently induced 2',5'-OAS and MxA mRNA expression in the control clones. Overexpression of SOCS-1 completely abolished both 2',5'-OAS and MxA mRNA expression, whereas SOCS-3 mainly inhibited 2',5'-OAS mRNA expression. Our results demonstrate that SOCS-1 and SOCS-3 proteins inhibit IFN-alpha-induced activation of the Jak-STAT pathway and expression of the antiviral proteins 2',5'-OAS and MxA. These data suggest a potential role of SOCS proteins in IFN resistance during antiviral treatment.

  4. Terpene Biosynthesis in Glandular Trichomes of Hop12[W][OA

    PubMed Central

    Wang, Guodong; Tian, Li; Aziz, Naveed; Broun, Pierre; Dai, Xinbin; He, Ji; King, Andrew; Zhao, Patrick X.; Dixon, Richard A.

    2008-01-01

    Hop (Humulus lupulus L. Cannabaceae) is an economically important crop for the brewing industry, where it is used to impart flavor and aroma to beer, and has also drawn attention in recent years due to its potential pharmaceutical applications. Essential oils (mono- and sesquiterpenes), bitter acids (prenylated polyketides), and prenylflavonoids are the primary phytochemical components that account for these traits, and all accumulate at high concentrations in glandular trichomes of hop cones. To understand the molecular basis for terpene accumulation in hop trichomes, a trichome cDNA library was constructed and 9,816 cleansed expressed sequence tag (EST) sequences were obtained from random sequencing of 16,152 cDNA clones. The ESTs were assembled into 3,619 unigenes (1,101 contigs and 2,518 singletons). Putative functions were assigned to the unigenes based on their homology to annotated sequences in the GenBank database. Two mono- and two sesquiterpene synthases identified from the EST collection were expressed in Escherichia coli. Hop MONOTERPENE SYNTHASE2 formed the linear monterpene myrcene from geranyl pyrophosphate, whereas hop SESQUITERPENE SYNTHASE1 (HlSTS1) formed both caryophyllene and humulene from farnesyl pyrophosphate. Together, these enzymes account for the production of the major terpene constituents of the hop trichomes. HlSTS2 formed the minor sesquiterpene constituent germacrene A, which was converted to β-elemene on chromatography at elevated temperature. We discuss potential functions for other genes expressed at high levels in developing hop trichomes. PMID:18775972

  5. Physiological Genomics of Response to Soil Drying in Diverse Arabidopsis Accessions[W][OA

    PubMed Central

    Des Marais, David L.; McKay, John K.; Richards, James H.; Sen, Saunak; Wayne, Tierney; Juenger, Thomas E.

    2012-01-01

    Arabidopsis thaliana, like many species, is characterized by abundant genetic variation. This variation is rapidly being cataloged at the sequence level, but careful dissection of genetic variation in whole-organism responses to stresses encountered in the natural environment are lacking; this functional variation can be exploited as a natural mutant screen to determine gene function. Here, we document physiological and transcriptomic response to soil drying in 17 natural accessions of Arabidopsis. By imposing ecologically realistic stress conditions, we found that acclimation in Arabidopsis involved a strong signature of increased investment in photosynthesis, carbohydrate turnover, and root growth. Our results extend previous work in the Columbia accession suggesting that abscisic acid signaling pathways play an important role in drought stress response. We also identified several mechanisms, including an increase in leaf nitrogen concentration and upregulation of two-component signaling relays, that were common to most natural accessions but had not been identified in studies using only the Columbia accession. Principal component analysis reveals strong correlations between suites of genes and specific physiological responses to stress. The functional variants we identified may represent adaptive mutations in natural habitats and useful variants for agronomic improvement of crop species. PMID:22408074

  6. Glutathione-Indole-3-Acetonitrile Is Required for Camalexin Biosynthesis in Arabidopsis thaliana[W][OA

    PubMed Central

    Su, Tongbing; Xu, Juan; Li, Yuan; Lei, Lei; Zhao, Luo; Yang, Hailian; Feng, Jidong; Liu, Guoqin; Ren, Dongtao

    2011-01-01

    Camalexin, a major phytoalexin in Arabidopsis thaliana, consists of an indole ring and a thiazole ring. The indole ring is produced from Trp, which is converted to indole-3-acetonitrile (IAN) by CYP79B2/CYP79B3 and CYP71A13. Conversion of Cys(IAN) to dihydrocamalexic acid and subsequently to camalexin is catalyzed by CYP71B15. Recent studies proposed that Cys derivative, not Cys itself, is the precursor of the thiazole ring that conjugates with IAN. The nature of the Cys derivative and how it conjugates to IAN and subsequently forms Cys(IAN) remain obscure. We found that protein accumulation of multiple glutathione S-transferases (GSTs), elevation of GST activity, and consumption of glutathione (GSH) coincided with camalexin production. GSTF6 overexpression increased and GSTF6-knockout reduced camalexin production. Arabidopsis GSTF6 expressed in yeast cells catalyzed GSH(IAN) formation. GSH(IAN), (IAN)CysGly, and γGluCys(IAN) were determined to be intermediates within the camalexin biosynthetic pathway. Inhibitor treatments and mutant analyses revealed the involvement of γ-glutamyl transpeptidases (GGTs) and phytochelatin synthase (PCS) in the catabolism of GSH(IAN). The expression of GSTF6, GGT1, GGT2, and PCS1 was coordinately upregulated during camalexin biosynthesis. These results suggest that GSH is the Cys derivative used during camalexin biosynthesis, that the conjugation of GSH with IAN is catalyzed by GSTF6, and that GGTs and PCS are involved in camalexin biosynthesis. PMID:21239642

  7. Arabidopsis PPR40 Connects Abiotic Stress Responses to Mitochondrial Electron Transport1[W][OA

    PubMed Central

    Zsigmond, Laura; Rigó, Gábor; Szarka, András; Székely, Gyöngyi; Ötvös, Krisztina; Darula, Zsuzsanna; Medzihradszky, Katalin F.; Koncz, Csaba; Koncz, Zsuzsa; Szabados, László

    2008-01-01

    Oxidative respiration produces adenosine triphosphate through the mitochondrial electron transport system controlling the energy supply of plant cells. Here we describe a mitochondrial pentatricopeptide repeat (PPR) domain protein, PPR40, which provides a signaling link between mitochondrial electron transport and regulation of stress and hormonal responses in Arabidopsis (Arabidopsis thaliana). Insertion mutations inactivating PPR40 result in semidwarf growth habit and enhanced sensitivity to salt, abscisic acid, and oxidative stress. Genetic complementation by overexpression of PPR40 complementary DNA restores the ppr40 mutant phenotype to wild type. The PPR40 protein is localized in the mitochondria and found in association with Complex III of the electron transport system. In the ppr40-1 mutant the electron transport through Complex III is strongly reduced, whereas Complex IV is functional, indicating that PPR40 is important for the ubiqinol-cytochrome c oxidoreductase activity of Complex III. Enhanced stress sensitivity of the ppr40-1 mutant is accompanied by accumulation of reactive oxygen species, enhanced lipid peroxidation, higher superoxide dismutase activity, and altered activation of several stress-responsive genes including the alternative oxidase AOX1d. These results suggest a close link between regulation of oxidative respiration and environmental adaptation in Arabidopsis. PMID:18305213

  8. Detection of bromine by ICP-oa-ToF-MS following photochemical vapor generation.

    PubMed

    Sturgeon, Ralph E

    2015-03-03

    A unique flow-through photochemical reactor is utilized for the generation of volatile methyl bromide from aqueous solutions of bromide and bromate ions in a medium of 2% acetic acid containing 3000 μg/mL NH4Cl. The volatile product is transported to a thin-film gas-liquid phase separator and directed to an inductively coupled plasma (ICP) tine-of-flight mass spectrometer for detection and quantitation using either of the (79)Br or (81)Br isotopes. Utilizing a sample flow rate of 3.3 mL/min and a 13 s irradiation time, a detection limit of 0.14 ng/mL is achieved, yielding a 17-fold enhancement over conventional solution nebulization. The estimated generation efficiency of 95% provides for a significant increase in analyte transport efficiency to the ICP. Precision of replicate measurement is 2.5% (RSD) at 20 ng/mL. The methodology was validated by successful determination of bromine in reference materials, including IRMM (BCR-611) low level bromide in groundwater, NIST SRM 1568b Rice Flour, and SRM 1632 bituminous coal.

  9. The Binding of Auxin to the Arabidopsis Auxin Influx Transporter AUX11[OA

    PubMed Central

    Carrier, David J.; Bakar, Norliza Tendot Abu; Swarup, Ranjan; Callaghan, Richard; Napier, Richard M.; Bennett, Malcolm J.; Kerr, Ian D.

    2008-01-01

    The cellular import of the hormone auxin is a fundamental requirement for the generation of auxin gradients that control a multitude of plant developmental processes. The AUX/LAX family of auxin importers, exemplified by AUX1 from Arabidopsis (Arabidopsis thaliana), has been shown to mediate auxin import when expressed heterologously. The quantitative nature of the interaction between AUX1 and its transport substrate indole-3-acetic acid (IAA) is incompletely understood, and we sought to address this in the present investigation. We expressed AUX1 to high levels in a baculovirus expression system and prepared membrane fragments from baculovirus-infected insect cells. These membranes proved suitable for determination of the binding of IAA to AUX1 and enabled us to determine a Kd of 2.6 μm, comparable with estimates for the Km for IAA transport. The efficacy of a number of auxin analogues and auxin transport inhibitors to displace IAA binding from AUX1 has also been determined and can be rationalized in terms of their physiological effects. Determination of the parameters describing the initial interaction between a plant transporter and its hormone ligand provides novel quantitative data for modeling auxin fluxes. PMID:18614710

  10. Abnormal Glycosphingolipid Mannosylation Triggers Salicylic Acid–Mediated Responses in Arabidopsis[W][OA

    PubMed Central

    Mortimer, Jenny C.; Yu, Xiaolan; Albrecht, Sandra; Sicilia, Francesca; Huichalaf, Mariela; Ampuero, Diego; Michaelson, Louise V.; Murphy, Alex M.; Matsunaga, Toshiro; Kurz, Samantha; Stephens, Elaine; Baldwin, Timothy C.; Ishii, Tadashi; Napier, Johnathan A.; Weber, Andreas P.M.; Handford, Michael G.; Dupree, Paul

    2013-01-01

    The Arabidopsis thaliana protein GOLGI-LOCALIZED NUCLEOTIDE SUGAR TRANSPORTER (GONST1) has been previously identified as a GDP-d-mannose transporter. It has been hypothesized that GONST1 provides precursors for the synthesis of cell wall polysaccharides, such as glucomannan. Here, we show that in vitro GONST1 can transport all four plant GDP-sugars. However, gonst1 mutants have no reduction in glucomannan quantity and show no detectable alterations in other cell wall polysaccharides. By contrast, we show that a class of glycosylated sphingolipids (glycosylinositol phosphoceramides [GIPCs]) contains Man and that this mannosylation is affected in gonst1. GONST1 therefore is a Golgi GDP-sugar transporter that specifically supplies GDP-Man to the Golgi lumen for GIPC synthesis. gonst1 plants have a dwarfed phenotype and a constitutive hypersensitive response with elevated salicylic acid levels. This suggests an unexpected role for GIPC sugar decorations in sphingolipid function and plant defense signaling. Additionally, we discuss these data in the context of substrate channeling within the Golgi. PMID:23695979

  11. Spatial Mapping of Lipids at Cellular Resolution in Embryos of Cotton[W][OA

    PubMed Central

    Horn, Patrick J.; Korte, Andrew R.; Neogi, Purnima B.; Love, Ebony; Fuchs, Johannes; Strupat, Kerstin; Borisjuk, Ljudmilla; Shulaev, Vladimir; Lee, Young-Jin; Chapman, Kent D.

    2012-01-01

    Advances in mass spectrometry (MS) have made comprehensive lipidomics analysis of complex tissues relatively commonplace. These compositional analyses, although able to resolve hundreds of molecular species of lipids in single extracts, lose the original cellular context from which these lipids are derived. Recently, high-resolution MS of individual lipid droplets from seed tissues indicated organelle-to-organelle variation in lipid composition, suggesting that heterogeneity of lipid distributions at the cellular level may be prevalent. Here, we employed matrix-assisted laser desorption/ionization–MS imaging (MALDI-MSI) approaches to visualize lipid species directly in seed tissues of upland cotton (Gossypium hirsutum). MS imaging of cryosections of mature cotton embryos revealed a distinct, heterogeneous distribution of molecular species of triacylglycerols and phosphatidylcholines, the major storage and membrane lipid classes in cotton embryos. Other lipids were imaged, including phosphatidylethanolamines, phosphatidic acids, sterols, and gossypol, indicating the broad range of metabolites and applications for this chemical visualization approach. We conclude that comprehensive lipidomics images generated by MALDI-MSI report accurate, relative amounts of lipid species in plant tissues and reveal previously unseen differences in spatial distributions providing for a new level of understanding in cellular biochemistry. PMID:22337917

  12. Determination of Oleanolic and Ursolic Acids in Hedyotis diffusa Using Hyphenated Ultrasound-Assisted Supercritical Carbon Dioxide Extraction and Chromatography

    PubMed Central

    Hong, Show-Jen

    2015-01-01

    Oleanolic acid (OA) and ursolic acid (UA) were extracted from Hedyotis diffusa using a hyphenated procedure of ultrasound-assisted and supercritical carbon dioxide (HSC–CO2) extraction at different temperatures, pressures, cosolvent percentages, and SC–CO2 flow rates. The results indicated that these parameters significantly affected the extraction yield. The maximal yields of OA (0.917 mg/g of dry plant) and UA (3.540 mg/g of dry plant) were obtained at a dynamic extraction time of 110 min, a static extraction time of 15 min, 28.2 MPa, and 56°C with a 12.5% (v/v) cosolvent (ethanol/water = 82/18, v/v) and SC–CO2 flowing at 2.3 mL/min (STP). The extracted yields were then analyzed by high performance liquid chromatography (HPLC) to quantify the OA and UA. The present findings revealed that H. diffusa is a potential source of OA and UA. In addition, using the hyphenated procedure for extraction is a promising and alternative process for recovering OA and UA from H. diffusa at high concentrations. PMID:26089939

  13. Determination of the spectrum of low molecular mass organic acids in urine by capillary electrophoresis with contactless conductivity and ultraviolet photometric detection--an efficient tool for monitoring of inborn metabolic disorders.

    PubMed

    Tůma, Petr; Samcová, Eva; Stulík, Karel

    2011-01-24

    A mixture of 29 organic acids (OAs) occurring in urine was analyzed by capillary electrophoresis (CE) with capacitively coupled contactless conductivity detection (C(4)D) and UV photometric detection. The optimized analytical system involved a 100 cm long polyacrylamide-coated capillary (50 μm i.d.) and the background electrolyte of 20mM 2-morpholinoethanesulfonic acid (MES)/NaOH+10% (v/v) methanol, pH 6.0 (pH is related to the 20mM MES/NaOH buffer in water). The LOD values obtained by C(4)D for the OAs which do not absorb UV radiation range from 0.6 μM (oxalic acid) to 6.8 μM (pyruvic acid); those obtained by UV photometry for the remaining OAs range from 2.9 μM (5-hydroxy-3-indoleacetic acid) to 10.2 μM (uric acid). The repeatability of the procedure developed is characterized by the coefficients of variation, which vary between 0.3% (tartaric acid) and 0.6% (5-hydroxy-3-indoleacetic acid) for the migration time and between 1.3% (tartaric acid) and 3.5% (lactic acid) for the peak area. The procedure permitted quantitation of 20 OAs in a real urine sample and was applied to monitoring of the occurrence of the inborn metabolic fault of methylmalonic aciduria.

  14. Persistent Contamination of Octopuses and Mussels with Lipophilic Shellfish Toxins during Spring Dinophysis Blooms in a Subtropical Estuary

    PubMed Central

    Mafra, Luiz L.; Lopes, Daiana; Bonilauri, Vanessa C.; Uchida, Hajime; Suzuki, Toshiyuki

    2015-01-01

    This study investigates the occurrence of diarrhetic shellfish toxins (DSTs) and their producing phytoplankton species in southern Brazil, as well as the potential for toxin accumulation in co-occurring mussels (Perna perna) and octopuses (Octopus vulgaris). During the spring in 2012 and 2013, cells of Dinophysis acuminata complex were always present, sometimes at relatively high abundances (max. 1143 cells L−1), likely the main source of okadaic acid (OA) in the plankton (max. 34 ng L−1). Dinophysis caudata occurred at lower cell densities in 2013 when the lipophilic toxins pectenotoxin-2 (PTX-2) and PTX-2 seco acid were detected in plankton and mussel samples. Here, we report for the first time the accumulation of DSTs in octopuses, probably linked to the consumption of contaminated bivalves. Perna perna mussels were consistently contaminated with different DSTs (max. 42 µg kg−1), and all octopuses analyzed (n = 5) accumulated OA in different organs/tissues: digestive glands (DGs) > arms > gills > kidneys > stomach + intestine. Additionally, similar concentrations of 7-O-palmytoyl OA and 7-O-palmytoly dinophysistoxin-1 (DTX-1) were frequently detected in the hepatopancreas of P. perna and DGs of O. vulgaris. Therefore, octopuses can be considered a potential vector of DSTs to both humans and top predators such as marine mammals. PMID:26096277

  15. Persistent Contamination of Octopuses and Mussels with Lipophilic Shellfish Toxins during Spring Dinophysis Blooms in a Subtropical Estuary.

    PubMed

    Mafra, Luiz L; Lopes, Daiana; Bonilauri, Vanessa C; Uchida, Hajime; Suzuki, Toshiyuki

    2015-06-18

    This study investigates the occurrence of diarrhetic shellfish toxins (DSTs) and their producing phytoplankton species in southern Brazil, as well as the potential for toxin accumulation in co-occurring mussels (Perna perna) and octopuses (Octopus vulgaris). During the spring in 2012 and 2013, cells of Dinophysis acuminata complex were always present, sometimes at relatively high abundances (max. 1143 cells L-1), likely the main source of okadaic acid (OA) in the plankton (max. 34 ng L-1). Dinophysis caudata occurred at lower cell densities in 2013 when the lipophilic toxins pectenotoxin-2 (PTX-2) and PTX-2 seco acid were detected in plankton and mussel samples. Here, we report for the first time the accumulation of DSTs in octopuses, probably linked to the consumption of contaminated bivalves. Perna perna mussels were consistently contaminated with different DSTs (max. 42 µg kg-1), and all octopuses analyzed (n = 5) accumulated OA in different organs/tissues: digestive glands (DGs) > arms > gills > kidneys > stomach + intestine. Additionally, similar concentrations of 7-O-palmytoyl OA and 7-O-palmytoly dinophysistoxin-1 (DTX-1) were frequently detected in the hepatopancreas of P. perna and DGs of O. vulgaris. Therefore, octopuses can be considered a potential vector of DSTs to both humans and top predators such as marine mammals.

  16. Major Proteome Variations Associated with Cherry Tomato Pericarp Development and Ripening[OA

    PubMed Central

    Faurobert, Mireille; Mihr, Christina; Bertin, Nadia; Pawlowski, Tomasz; Negroni, Luc; Sommerer, Nicolas; Causse, Mathilde

    2007-01-01

    Tomato (Solanum lycopersicum) is a model plant for studying fleshy fruit development. Several genetic and molecular approaches have been developed to increase our knowledge about the physiological basis of fruit growth, but very few data are yet available at the proteomic level. The main stages of fruit development were first determined through the dynamics of fruit diameter and pericarp cell number. Then, total proteins were extracted from pericarp tissue at six relevant developmental stages and separated by two-dimensional gel electrophoresis. Protein patterns were markedly different between stages. Proteins showing major variations were monitored. We identified 90 of 1,791 well-resolved spots either by matrix-assisted laser-desorption ionization time-of-flight peptide mass fingerprinting or liquid chromatography-mass spectrometry sequencing and expressed sequence tag database searching. Clustered correlation analysis results pointed out groups of proteins with similar expression profiles during fruit development. In young fruit, spots linked to amino acid metabolism or protein synthesis were mainly expressed during the cell division stage and down-regulated later. Some spots linked to cell division processes could be identified. During the cell expansion phase, spots linked to photosynthesis and proteins linked to cell wall formation transiently increased. In contrast, the major part of the spots related to C compounds and carbohydrate metabolism or oxidative processes were up-regulated during fruit development, showing an increase in spot intensity during development and maximal abundance in mature fruit. This was also the case for spots linked to stress responses and fruit senescence. We discuss protein variations, taking into account their potential role during fruit growth and comparing our results with already known variations at mRNA and metabolite-profiling levels. PMID:17208958

  17. Prunasin Hydrolases during Fruit Development in Sweet and Bitter Almonds1[C][W][OA

    PubMed Central

    Sánchez-Pérez, Raquel; Belmonte, Fara Sáez; Borch, Jonas; Dicenta, Federico; Møller, Birger Lindberg; Jørgensen, Kirsten

    2012-01-01

    Amygdalin is a cyanogenic diglucoside and constitutes the bitter component in bitter almond (Prunus dulcis). Amygdalin concentration increases in the course of fruit formation. The monoglucoside prunasin is the precursor of amygdalin. Prunasin may be degraded to hydrogen cyanide, glucose, and benzaldehyde by the action of the β-glucosidase prunasin hydrolase (PH) and mandelonitirile lyase or be glucosylated to form amygdalin. The tissue and cellular localization of PHs was determined during fruit development in two sweet and two bitter almond cultivars using a specific antibody toward PHs. Confocal studies on sections of tegument, nucellus, endosperm, and embryo showed that the localization of the PH proteins is dependent on the stage of fruit development, shifting between apoplast and symplast in opposite patterns in sweet and bitter cultivars. Two different PH genes, Ph691 and Ph692, have been identified in a sweet and a bitter almond cultivar. Both cDNAs are 86% identical on the nucleotide level, and their encoded proteins are 79% identical to each other. In addition, Ph691 and Ph692 display 92% and 86% nucleotide identity to Ph1 from black cherry (Prunus serotina). Both proteins were predicted to contain an amino-terminal signal peptide, with the size of 26 amino acid residues for PH691 and 22 residues for PH692. The PH activity and the localization of the respective proteins in vivo differ between cultivars. This implies that there might be different concentrations of prunasin available in the seed for amygdalin synthesis and that these differences may determine whether the mature almond develops into bitter or sweet. PMID:22353576

  18. Proline Dehydrogenase Contributes to Pathogen Defense in Arabidopsis1[C][W][OA

    PubMed Central

    Cecchini, Nicolás Miguel; Monteoliva, Mariela Inés; Alvarez, María Elena

    2011-01-01

    l-Proline (Pro) catabolism is activated in plants recovering from abiotic stresses associated with water deprivation. In this catabolic pathway, Pro is converted to glutamate by two reactions catalyzed by proline dehydrogenase (ProDH) and Δ1-pyrroline-5-carboxylate dehydrogenase (P5CDH), with Δ1-pyrroline-5-carboxylate (P5C) as the intermediate. Alternatively, under certain conditions, the P5C derived from Pro is converted back to Pro by P5C reductase, thus stimulating the Pro-P5C cycle, which may generate reactive oxygen species (ROS) as a consequence of the ProDH activity. We previously observed that Pro biosynthesis is altered in Arabidopsis (Arabidopsis thaliana) tissues that induce the hypersensitive response (HR) in response to Pseudomonas syringae. In this work, we characterized the Pro catabolic pathway and ProDH activity in this model. Induction of ProDH expression was found to be dependent on salicylic acid, and an increase in ProDH activity was detected in cells destined to die. To evaluate the role of ProDH in the HR, ProDH-silenced plants were generated. These plants displayed reduced ROS and cell death levels as well as enhanced susceptibility in response to avirulent pathogens. Interestingly, the early activation of ProDH was accompanied by an increase in P5C reductase but not in P5CDH transcripts, with few changes occurring in the Pro and P5C levels. Therefore, our results suggest that in wild-type plants, ProDH is a defense component contributing to HR and disease resistance, which apparently potentiates the accumulation of ROS. The participation of the Pro-P5C cycle in the latter response is discussed. PMID:21311034

  19. Clinical effectiveness in severe knee osteoarthritis after intra-articular platelet-rich plasma therapy in association with hyaluronic acid injection: three case reports

    PubMed Central

    Chen, Szu-Hsuan; Kuan, Ta-Shen; Kao, Mu-Jung; Wu, Wei-Ting; Chou, Li-Wei

    2016-01-01

    Osteoarthritis (OA) is a degenerative disorder resulting from loss of joint cartilage and underlying bone and causes pain and loss of function. The treatment of knee OA is still a challenge because of the poor self-regeneration capacity of cartilage. The nonsurgical interventions include control of the aggravating factor (such as weight control and the use of walking aids), symptomatic treatment (such as acetaminophen or nonsteroidal anti-inflammatory drugs), prolotherapy, and viscosupplementation. However, the combination of platelet-rich plasma (PRP) and hyaluronic acid (HA) has not been widely used because of lack of clinical evidence and several limitations in patients with severe knee OA. Three patients who suffered from knee pain and poor walking endurance were diagnosed with advanced knee OA. They underwent PRP treatment in association with intra-articular HA injection and showed pain relief and functional improvement. The follow-up standard weight-bearing X-ray images of knees also confirmed the improvement and indicated the possibility of regeneration of the articular cartilage. These cases provide clinical and radiographic evidence for a new therapy for advanced knee OA. This treatment strategy of PRP in association with HA injection can offer a chance to treat severe knee OA, rather than immediate surgery, or a chance for those who cannot undergo surgery. It can also postpone the need of arthroplasty and can significantly improve the daily activity function. PMID:27660427

  20. Clinical effectiveness in severe knee osteoarthritis after intra-articular platelet-rich plasma therapy in association with hyaluronic acid injection: three case reports.

    PubMed

    Chen, Szu-Hsuan; Kuan, Ta-Shen; Kao, Mu-Jung; Wu, Wei-Ting; Chou, Li-Wei

    Osteoarthritis (OA) is a degenerative disorder resulting from loss of joint cartilage and underlying bone and causes pain and loss of function. The treatment of knee OA is still a challenge because of the poor self-regeneration capacity of cartilage. The nonsurgical interventions include control of the aggravating factor (such as weight control and the use of walking aids), symptomatic treatment (such as acetaminophen or nonsteroidal anti-inflammatory drugs), prolotherapy, and viscosupplementation. However, the combination of platelet-rich plasma (PRP) and hyaluronic acid (HA) has not been widely used because of lack of clinical evidence and several limitations in patients with severe knee OA. Three patients who suffered from knee pain and poor walking endurance were diagnosed with advanced knee OA. They underwent PRP treatment in association with intra-articular HA injection and showed pain relief and functional improvement. The follow-up standard weight-bearing X-ray images of knees also confirmed the improvement and indicated the possibility of regeneration of the articular cartilage. These cases provide clinical and radiographic evidence for a new therapy for advanced knee OA. This treatment strategy of PRP in association with HA injection can offer a chance to treat severe knee OA, rather than immediate surgery, or a chance for those who cannot undergo surgery. It can also postpone the need of arthroplasty and can significantly improve the daily activity function.

  1. Effect of okadaic acid and calyculin-A, two protein phosphatase inhibitors, on thyrotropin-stimulated triiodothyronine secretion in cultured sheep thyroid cells.

    PubMed

    Arufe, M C; Beckett, G J; Durán, R; Alfonso, M

    1999-12-01

    We have studied the effect of two protein phosphatase inhibitors on thyrotropin (TSH)-stimulated triiodothyronine (T3) production by sheep thyroid cells grown in primary culture. Incubation of sheep thyrocytes with okadaic acid (OA) and calyculin-A (CL-A), two potent inhibitors of type 1 (PP1) and type 2A (PP2A) protein phosphatases, resulted in an increase of TSH-stimulated T3 production. This effect was detected using concentrations as low as 0.1 pM with OA and 1 fM with CL-A. An inhibitory effect on T3 production, due to cellular death, was observed with 6 nM OA and 1 nM CL-A. In the absence of TSH, OA or CL-A had no effect on T3 production by thyrocytes. Forskoline (10 microM), an activator of adenylate cyclase, increased the basal and TSH-stimulated T3 release by sheep thyroid cells; this effect was increased by OA in cells grown in the basal state but not in the presence of TSH. These results suggest that the marine toxins OA and CL-A, two potent inhibitors of PP-1 and PP-2A, have significant stimulatory effects on T3 secretion promoted by TSH and FK. These observations indicate that these proteins could be important mediators of thyroid hormone production.

  2. Heat transfer behaviour of silver particles containing oleic acid surfactant: application in a two phase closed rectangular cross sectional thermosyphon (RTPTC)

    NASA Astrophysics Data System (ADS)

    Bhuwakietkumjohn, N.; Parametthanuwat, T.

    2017-01-01

    This article focuses on heat transfer behaviour of silver nanoparticles containing oleic acid surfactant (OA) applied as a working fluid in a two-phase closed rectangular cross sectional thermosyphon (RTPTC). Thus, the OA could reduce the surface tension of the working fluid, which improved the colloidal ability and increased the lead-time period for nanoparticles to be uniformly dispersed. It highlights theories for investigating the effects on heat transfer characteristics of RTPTC such as heat transfer rate, thermal resistance, heat transfer coefficients and nanofluids behaviour. The most important heat transfer characteristic to be examined in this experiment is the relative thermal efficiency ( R T ). Five working fluids were tested, these include: de-ionized water; de-ionized water base with a silver nanoparticles concentration of 0.5 wt% (NP); and NP containing 0.5; 1; and 1.5 wt% of OA respectively. The results showed that 0.5 wt% NP containing 1 wt% OA produced the best results. It was further found that the heat transfer rate of 0.5 wt% NP containing 1 wt% of OA with a R T value of 1, was the highest across all experimental parameters studied. The NP containing OA demonstrated approximately 80 % higher heat transfer rate than the de-ionized water.

  3. Characterization of the serine acetyltransferase gene family of Vitis vinifera uncovers differences in regulation of OAS synthesis in woody plants

    PubMed Central

    Tavares, Sílvia; Wirtz, Markus; Beier, Marcel P.; Bogs, Jochen; Hell, Rüdiger; Amâncio, Sara

    2015-01-01

    In higher plants cysteine biosynthesis is catalyzed by O-acetylserine(thiol)lyase (OASTL) and represents the last step of the assimilatory sulfate reduction pathway. It is mainly regulated by provision of O-acetylserine (OAS), the nitrogen/carbon containing backbone for fixation of reduced sulfur. OAS is synthesized by Serine acetyltransferase (SERAT), which reversibly interacts with OASTL in the cysteine synthase complex (CSC). In this study we identify and characterize the SERAT gene family of the crop plant Vitis vinifera. The identified four members of the VvSERAT protein family are assigned to three distinct groups upon their sequence similarities to Arabidopsis SERATs. Expression of fluorescently labeled VvSERAT proteins uncover that the sub-cellular localization of VvSERAT1;1 and VvSERAT3;1 is the cytosol and that VvSERAT2;1 and VvSERAT2;2 localize in addition in plastids and mitochondria, respectively. The purified VvSERATs of group 1 and 2 have higher enzymatic activity than VvSERAT3;1, which display a characteristic C-terminal extension also present in AtSERAT3;1. VvSERAT1;1 and VvSERAT2;2 are evidenced to form the CSC. CSC formation activates VvSERAT2;2, by releasing CSC-associated VvSERAT2;2 from cysteine inhibition. Thus, subcellular distribution of SERAT isoforms and CSC formation in cytosol and mitochondria is conserved between Arabidopsis and grapevine. Surprisingly, VvSERAT2;1 lack the canonical C-terminal tail of plant SERATs, does not form the CSC and is almost insensitive to cysteine inhibition (IC50 = 1.9 mM cysteine). Upon sulfate depletion VvSERAT2;1 is strongly induced at the transcriptional level, while transcription of other VvSERATs is almost unaffected in sulfate deprived grapevine cell suspension cultures. Application of abiotic stresses to soil grown grapevine plants revealed isoform-specific induction of VvSERAT2;1 in leaves upon drought, whereas high light- or temperature- stress hardly trigger VvSERAT2;1 transcription. PMID:25741355

  4. Characterization of the serine acetyltransferase gene family of Vitis vinifera uncovers differences in regulation of OAS synthesis in woody plants.

    PubMed

    Tavares, Sílvia; Wirtz, Markus; Beier, Marcel P; Bogs, Jochen; Hell, Rüdiger; Amâncio, Sara

    2015-01-01

    In higher plants cysteine biosynthesis is catalyzed by O-acetylserine(thiol)lyase (OASTL) and represents the last step of the assimilatory sulfate reduction pathway. It is mainly regulated by provision of O-acetylserine (OAS), the nitrogen/carbon containing backbone for fixation of reduced sulfur. OAS is synthesized by Serine acetyltransferase (SERAT), which reversibly interacts with OASTL in the cysteine synthase complex (CSC). In this study we identify and characterize the SERAT gene family of the crop plant Vitis vinifera. The identified four members of the VvSERAT protein family are assigned to three distinct groups upon their sequence similarities to Arabidopsis SERATs. Expression of fluorescently labeled VvSERAT proteins uncover that the sub-cellular localization of VvSERAT1;1 and VvSERAT3;1 is the cytosol and that VvSERAT2;1 and VvSERAT2;2 localize in addition in plastids and mitochondria, respectively. The purified VvSERATs of group 1 and 2 have higher enzymatic activity than VvSERAT3;1, which display a characteristic C-terminal extension also present in AtSERAT3;1. VvSERAT1;1 and VvSERAT2;2 are evidenced to form the CSC. CSC formation activates VvSERAT2;2, by releasing CSC-associated VvSERAT2;2 from cysteine inhibition. Thus, subcellular distribution of SERAT isoforms and CSC formation in cytosol and mitochondria is conserved between Arabidopsis and grapevine. Surprisingly, VvSERAT2;1 lack the canonical C-terminal tail of plant SERATs, does not form the CSC and is almost insensitive to cysteine inhibition (IC50 = 1.9 mM cysteine). Upon sulfate depletion VvSERAT2;1 is strongly induced at the transcriptional level, while transcription of other VvSERATs is almost unaffected in sulfate deprived grapevine cell suspension cultures. Application of abiotic stresses to soil grown grapevine plants revealed isoform-specific induction of VvSERAT2;1 in leaves upon drought, whereas high light- or temperature- stress hardly trigger VvSERAT2;1 transcription.

  5. Enzyme-entrapped mesoporous silica for treatment of uric acid disorders.

    PubMed

    Muthukoori, Shanthini; Narayanan, Naagarajan; Chandra, Manuguri Sesha Sarath; Sethuraman, Swaminathan; Krishnan, Uma Maheswari

    2013-05-01

    Gout is an abnormality in the body resulting in the accumulation of uric acid mainly in joints. Dissolution of uric acid crystals into soluble allantoin by the enzyme uricase might provide a better alternative for the treatment of gout. This work aims to investigate the feasibility of a transdermal patch loaded with uricase for better patient compliance. Mesoporous silica (SBA-15) was chosen as the matrix for immobilisation of uricase. Highly oriented mesoporous SBA-15 was synthesized, characterized and uricase was physisorbed in the mesoporous material. The percentage adsorption and release of enzyme in borate buffer was monitored. The release followed linear kinetics and greater than 80% enzyme activity was retained indicating the potential of this system as an effective enzyme immobilization matrix. The enzyme permeability was studied with Wistar rat skin and human cadaver skin. It was found that in case of untreated rat skin 10% of enzyme permeated through skin in 100 h. The permeation increased by adding permeation enhancer (combination of oleic acid in propylene glycol (OA in PG)). The permeation enhancement was studied under two concentrations of OA in PG (1%, 5%) in both rat and human cadaver skin and it was found that 1% OA in PG showed better result in rat skin and 5% OA in PG showed good results in human cadaver skin.

  6. Hyaluronic acid reverses the abnormal synthetic activity of human osteoarthritic subchondral bone osteoblasts.

    PubMed

    Lajeunesse, Daniel; Delalandre, Aline; Martel-Pelletier, Johanne; Pelletier, Jean Pierre

    2003-10-01

    The underlying mechanisms responsible for both cartilage loss and subchondral bone changes in osteoarthritis (OA) remain unknown. It is becoming recognized that the extracellular matrix influences the metabolism of cells both in vivo and in vitro and can modify their responses to external stimuli. Indeed, the glycosaminoglycan/proteoglycan matrix is of major importance for the proliferation and/or differentiation of a number of cells. Here, we determined the potential role of hyaluronic acid (HA) of increasing molecular weight (MW) to alter the expression of metabolic markers and cytokine production by human osteoarthritic (OA) subchondral osteoblasts (Ob). Both 1,25(OH)(2)D(3)-induced alkaline phosphatase activity (ALPase) and osteocalcin release were increased in OA Ob when compared to normal. HA reduced osteocalcin release in OA Ob at MW of 300 and above, whereas HA failed to significantly modify ALPase. Parathyroid hormone (PTH) stimulated cyclic AMP (cAMP) formation by OA Ob. HA had a biphasic effect on this PTH-dependent activity, totally inhibiting cAMP formation at MW of 300 and 800. HA of increasing MW progressively reduced the levels of Prostaglandin E(2) (PGE(2)) and interleukin-6 (IL-6) produced by OA Ob. Interestingly, urokinase plasminogen activator (uPA) and and PA inhibitor-1 (PAI-1) levels were not significantly affected by HA of increasing MW; however, the PAI-1 to uPA ratio showed a slight, yet nonsignificant increase. Surprisingly, uPA activity was increased in OA Ob under the same conditions. Last, HA had no effect on the production of insulin-like growth factor-1 by these cells. Our data suggest that high MW HA can modify cellular parameters in OA Ob that are increased when compared to normal. The effect of HA on inflammatory mediators, such as PGE(2) and IL-6, and on uPA activity is more striking at higher MW as well. Taken together, these results could suggest that HA of increasing MW has positive effects on OA Ob by modifying their

  7. A Case of 9.7 Mb Terminal Xp Deletion Including OA1 Locus Associated with Contiguous Gene Syndrome

    PubMed Central

    Cho, Eun-Hae; Kim, Sook-Young

    2012-01-01

    Terminal or interstitial deletions of Xp (Xp22.2→Xpter) in males have been recognized as a cause of contiguous gene syndromes showing variable association of apparently unrelated clinical manifestations such as Leri-Weill dyschondrosteosis (SHOX), chondrodysplasia punctata (CDPX1), mental retardation (NLGN4), ichthyosis (STS), Kallmann syndrome (KAL1), and ocular albinism (GPR143). Here we present a case of a 13.5 yr old boy and sister with a same terminal deletion of Xp22.2 resulting in the absence of genes from the telomere of Xp to GPR143 of Xp22. The boy manifested the findings of all of the disorders mentioned above. We began a testosterone enanthate monthly replacement therapy. His sister, 11 yr old, manifested only Leri-Weill dyschondrosteosis, and had engaged in growth hormone therapy for 3 yr. To the best of our knowledge, this is the first report of a male with a 9.7 Mb terminal Xp deletion including the OA1 locus in Korea. PMID:23091330

  8. Regulation of melanosome number, shape and movement in the zebrafish retinal pigment epithelium by OA1 and PMEL

    PubMed Central

    Burgoyne, Thomas; O'Connor, Marie N.; Seabra, Miguel C.; Cutler, Daniel F.; Futter, Clare E.

    2015-01-01

    ABSTRACT Analysis of melanosome biogenesis in the retinal pigment epithelium (RPE) is challenging because it occurs predominantly in a short embryonic time window. Here, we show that the zebrafish provides an ideal model system for studying this process because in the RPE the timing of melanosome biogenesis facilitates molecular manipulation using morpholinos. Morpholino-mediated knockdown of OA1 (also known as GPR143), mutations in the human homologue of which cause the most common form of human ocular albinism, induces a major reduction in melanosome number, recapitulating a key feature of the mammalian disease where reduced melanosome numbers precede macromelanosome formation. We further show that PMEL, a key component of mammalian melanosome biogenesis, is required for the generation of cylindrical melanosomes in zebrafish, which in turn is required for melanosome movement into the apical processes and maintenance of photoreceptor integrity. Spherical and cylindrical melanosomes containing similar melanin volumes co-exist in the cell body but only cylindrical melanosomes enter the apical processes. Taken together, our findings indicate that melanosome number and shape are independently regulated and that melanosome shape controls a function in the RPE that depends on localisation in the apical processes. PMID:25690007

  9. Nonperturbative O(a) improvement of Wilson quark action in three-flavor QCD with plaquette gauge action

    SciTech Connect

    Yamada, N.; Hashimoto, S.; Kaneko, T.; Tsutsui, N.; Aoki, S.; Taniguchi, Y.; Fukugita, M.; Ishikawa, K-I.; Okawa, M.; Ishizuka, N.; Iwasaki, Y.; Kanaya, K.; Kuramashi, Y.; Ukawa, A.; Yoshie, T.

    2005-03-01

    We perform a nonperturbative determination of the O(a)-improvement coefficient c{sub SW} for the Wilson quark action in three-flavor QCD with the plaquette gauge action. Numerical simulations are carried out in a range of {beta}=12.0-5.2 on a single lattice size of 8{sup 3}x16 employing the Schroedinger functional setup of lattice QCD. As our main result, we obtain an interpolation formula for c{sub SW} and the critical hopping parameter K{sub c} as a function of the bare coupling. This enables us to remove the O(a) scaling violation from physical observables in future numerical simulation in the wide range of {beta}. Our analysis with a perturbatively modified improvement condition for c{sub SW} suggests that finite volume effects in c{sub SW} are not large on the 8{sup 3}x16 lattice. We investigate N{sub f} dependence of c{sub SW} by additional simulations for N{sub f}=4, 2, and 0 at {beta}=9.6. As a preparatory step for this study, we also determine c{sub SW} in two-flavor QCD at {beta}=5.2. At this {beta}, several groups have carried out large-scale calculations of the hadron spectrum, while no systematic determination of c{sub SW} has been performed.

  10. Impact of IL28B and OAS gene family polymorphisms on interferon treatment response in Caucasian children chronically infected with hepatitis B virus

    PubMed Central

    Domagalski, Krzysztof; Pawłowska, Małgorzata; Zaleśna, Agnieszka; Pilarczyk, Małgorzata; Rajewski, Paweł; Halota, Waldemar; Tretyn, Andrzej

    2016-01-01

    AIM To investigate the impact of IL28B and OAS gene polymorphisms on interferon treatment responses in children with chronic hepatitis B. METHODS We enrolled 52 children (between the ages of 4 and 18) with hepatitis B e antigen-negative chronic hepatitis B (CHB), who were treated with pegylated interferon alfa for 48 wk. Single nucleotide polymorphisms in the OAS1 (rs1131476), OAS2 (rs1293747), OAS3 (rs2072136), OASL (rs10849829) and IL28B (rs12979860, rs12980275 and rs8099917) genes were studied to examine their associations with responses to IFN treatment in paediatric patients. We adopted two criteria for the therapeutic response, achieving an hepatitis B virus (HBV) DNA level < 2000 IU/mL and normalization of ALT activity (< 40 IU/L). To perform the analyses, we compared the patients in terms of achieving a partial response (PR) and a complete response (CR) upon measurement at the 24-wk post-treatment follow-up. RESULTS The PR and CR rates were 80.8% and 42.3%, respectively. Factors such as age, gender and liver histology had no impact on the type of response (partial or complete). A statistically significant relationship between higher baseline HBV DNA and ALT activity levels and lower rates of PR and CR was shown (P < 0.05). The allele association analysis revealed that only the IL-28B rs12979860 (C vs T) and IL28B rs12980275 (A vs G) markers significantly affected the achievement of PR (P = 0.021, OR = 3.3, 95%CI: 1.2-9.2 and P = 0.014, OR = 3.7, 95%CI: 1.3-10.1, respectively). However, in the genotype analysis, only IL-28B rs12980275 was significantly associated with PR (AA vs AG-GG, P = 0.014, OR = 10.9, 95%CI: 1.3-93.9). The association analysis for CR showed that the TT genotype of IL28B rs12979860 was present only in the no-CR group (P = 0.033) and the AA genotype of OASL rs10849829 was significantly more frequent in the no-CR group (P = 0.044, OR = 0.26, 95%CI: 0.07-0.88). The haplotype analysis revealed significant associations between PR and CR and

  11. Hypolipidemic effect of oleanolic acid is mediated by the miR-98-5p/PGC-1β axis in high-fat diet-induced hyperlipidemic mice.

    PubMed

    Chen, Siyu; Wen, Xiaoan; Zhang, Wenxiang; Wang, Chen; Liu, Jun; Liu, Chang

    2017-03-01

    Oleanolic acid (OA) is an active component of the traditional Chinese herb Olea europaea L. and has been found to exhibit a significant lipid-lowering effect; however, its direct molecular target is still unknown, which limits its clinical application and the possible structure modification to improve its beneficial functions. In this regard, we carried out the present study to identify potential hepatic targets of OA to mediate its lipid-lowering effect. We found that both acute and chronic OA treatments reduced serum levels of triglycerides, total cholesterol, and LDL cholesterol, and decreased hepatic expression levels of peroxisome proliferator-activated receptor-γ coactivator-1β (PGC-1β), which is an important regulator in maintaining hepatic lipid homeostasis, and its downstream target genes. Of note, liver-specific knockdown of PGC-1β recapitulated the hypolipidemic effects of OA. At the molecular level, OA accelerated mRNA degradation of PGC-1β. Microarray analysis revealed a host of microRNAs that potentially mediate OA-induced PGC-1β mRNA degradation, among which, miR-98-5p significantly inhibited activity of Pgc-1β 3' UTR as well as PGC-1β expression and promoted its mRNA degradation. Conversely, miR-98-5p inhibitors blunted the inhibitory effects of OA on PGC-1β expression. Collectively, our data demonstrated that OA ameliorated hyperlipidemia, likely via regulation of the miR-98-5p/PGC-1β axis.-Chen, S., Wen, X., Zhang, W., Wang, C., Liu, J., Liu, C. Hypolipidemic effect of oleanolic acid is mediated by the miR-98-5p/PGC-1β axis in high-fat diet-induced hyperlipidemic mice.

  12. Generation and esterification of electrophilic fatty acid nitroalkenes in triacylglycerides.

    PubMed

    Fazzari, Marco; Khoo, Nicholas; Woodcock, Steven R; Li, Lihua; Freeman, Bruce A; Schopfer, Francisco J

    2015-10-01

    Electrophilic fatty acid nitroalkenes (NO(2)-FA) are products of nitric oxide and nitrite-mediated unsaturated fatty acid nitration. These electrophilic products induce pleiotropic signaling actions that modulate metabolic and inflammatory responses in cell and animal models. The metabolism of NO(2)-FA includes reduction of the vinyl nitro moiety by prostaglandin reductase-1, mitochondrial β-oxidation, and Michael addition with low molecular weight nucleophilic amino acids. Complex lipid reactions of fatty acid nitroalkenes are not well defined. Herein we report the detection and characterization of NO(2)-FA-containing triacylglycerides (NO(2)-FA-TAG) via mass spectrometry-based methods. In this regard, unsaturated fatty acids of dietary triacylglycerides are targets for nitration reactions during gastric acidification, where NO(2)-FA-TAG can be detected in rat plasma after oral administration of nitro-oleic acid (NO(2)-OA). Furthermore, the characterization and profiling of these species, including the generation of beta oxidation and dehydrogenation products, could be detected in NO(2)-OA-supplemented adipocytes. These data revealed that NO(2)-FA-TAG, formed by either the direct nitration of esterified unsaturated fatty acids or the incorporation of nitrated free fatty acids into triacylglycerides, contribute to the systemic distribution of these reactive electrophilic mediators and may serve as a depot for subsequent mobilization by lipases to in turn impact adipocyte homeostasis and tissue signaling events.

  13. Generation and esterification of electrophilic fatty acid nitroalkenes in triacylglycerides

    PubMed Central

    Fazzari, Marco; Khoo, Nicholas; Woodcock, Steven R.; Li, Lihua; Freeman, Bruce A.; Schopfer, Francisco J.

    2015-01-01

    Electrophilic fatty acid nitroalkenes (NO2-FA) are products of nitric oxide and nitrite-mediated unsaturated fatty acid nitration. These electrophilic products induce pleiotropic signaling actions that modulate metabolic and inflammatory responses in cell and animal models. The metabolism of NO2-FA includes reduction of the vinyl nitro moiety by prostaglandin reductase-1, mitochondrial β–oxidation and Michael addition with low molecular weight nucleophilic amino acids. Complex lipid reactions of fatty acid nitroalkenes are not well defined. Herein we report the detection and characterization of NO2-FA-containing triacylglycerides (NO2-FA-TAG) via mass spectrometry-based methods. In this regard, unsaturated fatty acids of dietary triacylglycerides are targets for nitration reactions during gastric acidification, where NO2-FA-TAG can be detected in rat plasma after oral administration of nitro-oleic acid (NO2-OA). Furthermore, the characterization and profiling of these species, including the generation of beta oxidation and dehydrogenation products, could be detected in NO2-OA supplemented adipocytes. These data revealed that NO2-FA-TAG, formed by either the direct nitration of esterified unsaturated fatty acids or the incorporation of nitrated free fatty acids into triacylglycerides, contribute to the systemic distribution of these reactive electrophilic mediators and may serve as a depot for subsequent mobilization by lipases to in turn impact adipocyte homeostasis and tissue signaling events. PMID:26066303

  14. Nitro-oleic acid modulates classical and regulatory activation of macrophages and their involvement in pro-fibrotic responses.

    PubMed

    Ambrozova, Gabriela; Martiskova, Hana; Koudelka, Adolf; Ravekes, Thorben; Rudolph, Tanja K; Klinke, Anna; Rudolph, Volker; Freeman, Bruce A; Woodcock, Steven R; Kubala, Lukas; Pekarova, Michaela

    2016-01-01

    Inflammation is an immune response triggered by microbial invasion and/or tissue injury. While acute inflammation is directed toward invading pathogens and injured cells, thus enabling tissue regeneration, chronic inflammation can lead to severe pathologies and tissue dysfunction. These processes are linked with macrophage polarization into specific inflammatory "M1-like" or regulatory "M2-like" subsets. Nitro-fatty acids (NO2-FAs), produced endogenously as byproducts of metabolism and oxidative inflammatory conditions, may be useful for treating diseases associated with dysregulated immune homeostasis. The goal of this study was to characterize the role of nitro-oleic acid (OA-NO2) in regulating the functional specialization of macrophages induced by bacterial lipopolysaccharide or interleukin-4, and to reveal specific signaling mechanisms which can account for OA-NO2-dependent modulation of inflammation and fibrotic responses. Our results show that OA-NO2 inhibits lipopolysaccharide-stimulated production of both pro-inflammatory and immunoregulatory cytokines (including transforming growth factor-β) and inhibits nitric oxide and superoxide anion production. OA-NO2 also decreases interleukin-4-induced macrophage responses by inhibiting arginase-I expression and transforming growth factor-β production. These effects are mediated via downregulation of signal transducers and activators of transcription, mitogen-activated protein kinase and nuclear factor-кB signaling responses. Finally, OA-NO2 inhibits fibrotic processes in an in vivo model of angiotensin II-induced myocardial fibrosis by attenuating expression of α-smooth muscle actin, systemic transforming growth factor-β levels and infiltration of both "M1-" and "M2-like" macrophage subsets into afflicted tissue. Overall, the electrophilic fatty acid derivative OA-NO2 modulates a broad range of "M1-" and "M2-like" macrophage functions and represents a potential therapeutic approach to target diseases

  15. Synthesis and optimization ring opening of monoepoxide linoleic acid using p-toluenesulfonic acid.

    PubMed

    Salimon, Jumat; Abdullah, Bashar Mudhaffar; Yusop, Rahimi M; Salih, Nadia; Yousif, Emad

    2013-01-01

    Biolubricant base oils, 9,12-hydroxy-10,13-oleioxy-12-octadecanoic acid (HYOOA) was synthesized based on the esterification reaction of Monoepoxide linoleic acid 9(12)-10(13)-monoepoxy 12(9)-octadecanoic acid (MEOA) with oleic acid (OA) and catalyzed by p-Toluenesulfonic acid. The optimum conditions for the experiment using D-optimal design to obtain high yield% of 84.61, conversion% of 83.54 and lowest OOC% of 0.05 were predicted at OA/MEOA ratio of 0.2:1 (mol/mol), PTSA/MEOA ratio of 0.4:1 (mol/mol), reaction temperature at 110°C, and reaction time at 4.5 h. The FTIR peaks of HYOOA indicate the disappearance of the absorption band at 820 cm(-1), which belongs to the oxirane ring. (13)C and (1)H NMR spectra analyses confirmed the result of HYOOA with appearance carbon-ester (C = O) chemical shift at 174.1 ppm and at 4.06 ppm for (13)C and (1)H NMR respectively.

  16. Oleanolic Acid Inhibits High Salt-Induced Exaggeration of Warburg-like Metabolism in Breast Cancer Cells.

    PubMed

    Amara, Suneetha; Zheng, Mu; Tiriveedhi, Venkataswarup

    2016-09-01

    Cancer cells have a proliferative advantage by utilizing intermediates of aerobic glycolysis (Warburg effect) for their macromolecule synthesis. Although the exact causes of this Warburg effect are unclear, high osmotic stress in solid tumor microenvironment is considered one of the important factors. Oleanolic acid (OA) is known to exert anti-inflammatory and anti-cancer effect. In our current studies, using breast cancer cell lines, we determined the protective role of OA in high salt-mediated osmotic stress-induced cancer growth. Hypertonic (0.16 M NaCl) culture conditions enhanced the cancer cell growth (26 %, p < 0.05) and aerobic glycolysis as marked by increased glucose consumption (34 %, p < 0.05) and lactate production (25 %, p < 0.05) over untreated cells. This effect was associated with increased expression and activity of key rate-limiting enzymes of aerobic glycolysis, namely hexokinase, pyruvate kinase type M2, and lactate dehydrogenase A. Interestingly, this high salt-mediated enhanced expression of aerobic glycolytic enzymes was efficiently reversed by OA along with the decreased cancer cell proliferation. In cancer cells, enhanced aerobic glycolysis is associated with the decreased mitochondrial activity and mitochondrial-associated caspase activity. As expected, high salt further inhibited the mitochondrial related cytochrome oxidase and caspase-3 activity. However, OA efficiently reversed the high salt-mediated inhibition of cytochrome oxidase, caspase activity, and pro-apoptotic Bax expression, thus suggesting that OA induced mitochondrial activity and enhanced apoptosis. Taken together, our data indicate that OA efficiently reverses the enhanced Warburg-like metabolism induced by high salt-mediated osmotic stress along with potential application of OA in anti-cancer therapy.

  17. Knee Osteoarthritis Injection Choices: Platelet- Rich Plasma (PRP) Versus Hyaluronic Acid (A one-year randomized clinical trial)

    PubMed Central

    Raeissadat, Seyed Ahmad; Rayegani, Seyed Mansoor; Hassanabadi, Hossein; Fathi, Mohammad; Ghorbani, Elham; Babaee, Marzieh; Azma, Kamran

    2015-01-01

    INTRODUCTION Knee osteoarthritis (OA) is the most common articular disease. Different methods are used to alleviate the symptoms of patients with knee OA, including analgesics, physical therapy, exercise prescription, and intra-articular injections (glucocorticoids, hyaluronic acid [HA], etc). New studies have focused on modern therapeutic methods that stimulate cartilage healing process and improve the damage, including the use of platelet-rich plasma (PRP) as a complex of growth factors. Due to the high incidence of OA and its consequences, we decided to study the long-term effect of intraarticular injection of PRP and HA on clinical outcome and quality of life of patients with knee OA. METHOD This non-placebo-controlled randomized clinical trial involved 160 patients affected by knee OA, grade 1–4 of Kellgren–Lawrence scale. In the PRP group (n = 87), two intra-articular injections at 4-week interval were applied, and in the HA group (n = 73), three doses of intra-articular injection at 1-week interval were applied. All patients were prospectively evaluated before and at 12 months after the treatment by Western Ontario and McMaster Universities Arthritis Index (WOMAC) and SF-36 questionnaires. The results were analyzed using SPSS 16.1 software (RCT code: IRCT2014012113442N5). RESULTS At the 12-month follow-up, WOMAC pain score and bodily pain significantly improved in both groups; however, better results were determined in the PRP group compared to the HA group (P < 0.001). Other WOMAC and SF-36 parameters improved only in the PRP group. More improvement (but not statistically significant) was achieved in patients with grade 2 OA in both the groups. CONCLUSION This study suggests that PRP injection is more efficacious than HA injection in reducing symptoms and improving quality of life and is a therapeutic option in select patients with knee OA who have not responded to conventional treatment. PMID:25624776

  18. Oleanolic acid prevents progression of streptozotocin induced diabetic nephropathy and protects renal microstructures in Sprague Dawley rats

    PubMed Central

    Dubey, Vishal K.; Patil, Chandragouda R.; Kamble, Sarika M.; Tidke, Priti S.; Patil, Kalpesh R.; Maniya, Pragnesh J.; Jadhav, Ramchandra B.; Patil, Sudha P.

    2013-01-01

    Objective: To study the effect of oleanolic acid (OA) on streptozotocin induced diabetic nephropathy in Sprague Dawley rats. Materials and Methods: Four weeks after intra-peritoneal injection of streptozotocin (STZ; 55 mg/kg), the rats with proteinuria were grouped as: Control (non-diabetic, treated orally with vehicle), diabetic control (treated orally with vehicle) and three diabetic groups receiving 20, 40 and 60 mg/kg/day oral doses of OA. At the end of 8 weeks, urine and serum samples from the rats were processed for determination of creatinine, BUN and GFR. The kidney samples were processed for determination of weight changes, oxidative stress related parameters like catalase, superoxide dismutase and reduced glutathione levels. A part of one kidney from each rat was used for transmission electron microscopy (TEM). Result: As evident in TEM, OA inhibited the nephropathy induced alterations in podocyte integrity, basement membrane thickness and spacing between the podocytes at 60 mg/kg dose. It increased GFR and reduced oxidative stress in the kidneys in a dose dependent manner. These findings conclusively demonstrate the efficacy of OA in diabetic nephropathy. Significant decrease in the oxidative stress in kidneys indicates the role of anti-oxidant mechanisms in the effects of OA. However, OA is known to act through multiple mechanisms like inhibition of the generation of advanced glycation end products and improving the insulin secretion. These mechanisms might have contributed to its efficacy. Conclusion: These results conclusively demonstrate the efficacy of OA in diabetic nephropathy through its possible antioxidant activity. PMID:23662024

  19. Comparative Proteomic Study of Fatty Acid-treated Myoblasts Reveals Role of Cox-2 in Palmitate-induced Insulin Resistance.

    PubMed

    Chen, Xiulan; Xu, Shimeng; Wei, Shasha; Deng, Yaqin; Li, Yiran; Yang, Fuquan; Liu, Pingsheng

    2016-02-22

    Accumulated studies demonstrate that saturated fatty acids (FAs) such as palmitic acid (PA) inhibit insulin signaling in skeletal muscle cells and monounsaturated fatty acids such as oleic acid (OA) reverse the effect of PA on insulin signaling. The detailed molecular mechanism of these opposite effects remains elusive. Here we provide a comparative proteomic study of skeletal myoblast cell line C2C12 that were untreated or treated with PA, and PA plus OA. A total of 3437 proteins were quantified using SILAC in this study and 29 proteins fall into the pattern that OA reverses PA effect. Expression of some these proteins were verified using qRT-PCR and Western blot. The most significant change was cyclooxygenase-2 (Cox-2). In addition to whole cell comparative proteomic study, we also compared lipid droplet (LD)-associated proteins and identified that Cox-2 was one of three major altered proteins under the FA treatment. This finding was then confirmed using immunofluorescence. Finally, Cox-2 selective inhibitor, celecoxib protected cells from PA-reduced insulin signaling Akt phosphorylation. Together, these results not only provide a dataset of protein expression change in FA treatment but also suggest that Cox-2 and lipid droplets (LDs) are potential players in PA- and OA-mediated cellular processes.

  20. Fatty acid fouling of forward osmosis membrane: Effects of pH, calcium, membrane orientation, initial permeate flux and foulant composition.

    PubMed

    Zhao, Pin; Gao, Baoyu; Yue, Qinyan; Liu, Pan; Shon, Ho Kyong

    2016-08-01

    Octanoic acid (OA) was selected to represent fatty acids in effluent organic matter (EOM). The effects of feed solution (FS) properties, membrane orientation and initial permeate flux on OA fouling in forward osmosis (FO) were investigated. The undissociated OA formed a cake layer quickly and caused the water flux to decline significantly in the initial 0.5hr at unadjusted pH3.56; while the fully dissociated OA behaved as an anionic surfactant and promoted the water permeation at an elevated pH of 9.00. Moreover, except at the initial stage, the sudden decline of water flux (meaning the occurrence of severe membrane fouling) occurred in two conditions: 1. 0.5mmol/L Ca(2+), active layer facing draw solution (AL-DS) and 1.5mol/L NaCl (DS); 2. No Ca(2+), active layer-facing FS (AL-FS) and 4mol/L NaCl (DS). This demonstrated that cake layer compaction or pore blocking occurred only when enough foulants were absorbed into the membrane surface, and the water permeation was high enough to compact the deposit inside the porous substrate. Furthermore, bovine serum albumin (BSA) was selected as a co-foulant. The water flux of both co-foulants was between the fluxes obtained separately for the two foulants at pH3.56, and larger than the two values at pH9.00. This manifested that, at pH3.56, BSA alleviated the effect of the cake layer caused by OA, and OA enhanced BSA fouling simultaneously; while at pH9.00, the mutual effects of OA and BSA eased the membrane fouling.

  1. Early Genotoxic and Cytotoxic Effects of the Toxic Dinoflagellate Prorocentrum lima in the Mussel Mytilus galloprovincialis

    PubMed Central

    Prego-Faraldo, María Verónica; Valdiglesias, Vanessa; Laffon, Blanca; Mendez, Josefina; Eirin-Lopez, Jose M.

    2016-01-01

    Okadaic acid (OA) and dinophysistoxins (DTXs) are the main toxins responsible for diarrhetic shellfish poisoning (DSP) intoxications during harmful algal blooms (HABs). Although the genotoxic and cytotoxic responses to OA have been evaluated in vitro, the in vivo effects of these toxins have not yet been fully explored. The present work fills this gap by evaluating the in vivo effects of the exposure to the DSP-toxin-producing dinoflagellate Prorocentrum lima during the simulation of an early HAB episode in the mussel Mytilus galloprovincialis. The obtained results revealed that in vivo exposure to this toxic microalgae induced early genotoxicity in hemocytes, as a consequence of oxidative DNA damage. In addition, the DNA damage observed in gill cells seems to be mainly influenced by exposure time and P. lima concentration, similarly to the case of the oxidative damage found in hemocytes exposed in vitro to OA. In both cell types, the absence of DNA damage at low toxin concentrations is consistent with the notion suggesting that this level of toxicity does not disturb the antioxidant balance. Lastly, in vivo exposure to growing P. lima cell densities increased apoptosis but not necrosis, probably due to the presence of a high number of protein apoptosis inhibitors in molluscs. Overall, this work sheds light into the in vivo genotoxic and cytotoxic effects of P. lima. In doing so, it also demonstrates for the first time the potential of the modified (OGG1) comet assay for assessing oxidative DNA damage caused by marine toxins in marine invertebrates. PMID:27231936

  2. Temperature and base requirements for the alkaline hydrolysis of okadaite's esters.

    PubMed

    Rodrigues, Susana M; Vale, Paulo

    2009-06-01

    Portuguese bivalves are recurrently contaminated with okadaic acid (OA) and dinophysistoxin-2 (DTX2), found mainly in esterified forms. Throughout the years different conditions have been reported in the literature for releasing the parent toxins through an alkaline hydrolysis step, in order to simplify their detection by HPLC-FLD or LC-MS. In order to clearly understand toxin stability and reaction end-point the binominous temperature/time course and base concentration were studied using naturally contaminated bivalve samples. The results showed a strong temperature dependence of the reaction. At 60 degrees C and 70 degrees C the hydrolysis was fast, and 40min were sufficient for maximal recovery of OA and DTX2, while at 40 degrees C and 50 degrees C it was only complete after 100min and 60min, respectively. At room temperature the reaction was slow and incomplete even after 2h. Stability of OA and DTX2 in semi-purified bivalve matrix at 70 degrees C for 2h was demonstrated. Concentrations of sodium hydroxide lower than 2.5M, corresponding to a final incubation concentration of 0.23M, resulted in incomplete release of parent toxins, demonstrating that high concentrations are needed when taking into account the dilution in the supernatant extract.

  3. Two simple models for accounting mussel contamination with diarrhoetic shellfish poisoning toxins at Aveiro lagoon: Control by rainfall and atmospheric forcing

    NASA Astrophysics Data System (ADS)

    Vale, Paulo

    2012-02-01

    At Aveiro lagoon (Portuguese northwest coast) bivalve contamination with diarrhoetic shellfish poisoning toxins (DSTs), okadaic acid (OA) and dinophysistoxin-2 (DTX2), is a recurrent annual phenomenon seriously affecting seafood safety. The influence of meteorological parameters was studied to understand accumulation of DSTs in mussels, related to the blooming of the causative toxic microalgae, belonging to genus Dinophysis. Two simplified models were useful in predicting the accumulation of DSTs in blue mussels from this lagoon. Either the May river drainage or the rainfall accumulated from January through May could adequately predict the severity of OA accumulated from predation upon Dinophysis acuminata during June/July. In both cases a linear relationship was obtained, with correlation coefficients of 0.85 or greater. Winds with a west direction favour coastal concentration of Dinophysis acuta in Aveiro region. Both OA and DTX2 contamination increased exponentially in September/October with the cumulative number of days with W-wind orientation in the preceding August (correlation coefficients greater than 0.92). This relationship was attributed to the quadratic effect of wind stress on surface currents. August is a transitional month, when the continental runoff effect upon Dinophysis acuminata can still be observed and Dinophysis acuta advection may be promoted by westerly winds occurring in July. The frequency of periods with northerly winds in July can halt accumulation of toxins derived from Dinophysis acuta.

  4. Early Genotoxic and Cytotoxic Effects of the Toxic Dinoflagellate Prorocentrum lima in the Mussel Mytilus galloprovincialis.

    PubMed

    Prego-Faraldo, María Verónica; Valdiglesias, Vanessa; Laffon, Blanca; Mendez, Josefina; Eirin-Lopez, Jose M

    2016-05-24

    Okadaic acid (OA) and dinophysistoxins (DTXs) are the main toxins responsible for diarrhetic shellfish poisoning (DSP) intoxications during harmful algal blooms (HABs). Although the genotoxic and cytotoxic responses to OA have been evaluated in vitro, the in vivo effects of these toxins have not yet been fully explored. The present work fills this gap by evaluating the in vivo effects of the exposure to the DSP-toxin-producing dinoflagellate Prorocentrum lima during the simulation of an early HAB episode in the mussel Mytilus galloprovincialis. The obtained results revealed that in vivo exposure to this toxic microalgae induced early genotoxicity in hemocytes, as a consequence of oxidative DNA damage. In addition, the DNA damage observed in gill cells seems to be mainly influenced by exposure time and P. lima concentration, similarly to the case of the oxidative damage found in hemocytes exposed in vitro to OA. In both cell types, the absence of DNA damage at low toxin concentrations is consistent with the notion suggesting that this level of toxicity does not disturb the antioxidant balance. Lastly, in vivo exposure to growing P. lima cell densities increased apoptosis but not necrosis, probably due to the presence of a high number of protein apoptosis inhibitors in molluscs. Overall, this work sheds light into the in vivo genotoxic and cytotoxic effects of P. lima. In doing so, it also demonstrates for the first time the potential of the modified (OGG1) comet assay for assessing oxidative DNA damage caused by marine toxins in marine invertebrates.

  5. Quantitative determination of marine lipophilic toxins in mussels, oysters and cockles using liquid chromatography-mass spectrometry: inter-laboratory validation study.

    PubMed

    van den Top, H J; Gerssen, A; McCarron, P; van Egmond, H P

    2011-12-01

    Thirteen laboratories participated in an inter-laboratory study to evaluate the method performance characteristics of a liquid chromatography-tandem mass spectrometric method (LC-MS/MS) for marine lipophilic shellfish toxins. Method performance characteristics were evaluated for mussel (Mytilus edulis), oyster (Crassostrea gigas) and cockle (Cerastoderma edule) matrices. The specific toxin analogues tested included okadaic acid (OA), dinophysistoxins-1 and -2 (DTX1, -2), azaspiracids-1, -2 and -3 (AZA1, -2, -3), pectenotoxin-2 (PTX2), yessotoxin (YTX), and 45-OH-yessotoxin (45-OH-YTX). The instrumental technique was developed as an alternative to the still widely applied biological methods (mouse or rat bioassay). Validation was conducted according to the AOAC-harmonised protocol for the design, conduct and interpretation of method-performance studies. Eight different test materials were sent as blind duplicates to the participating laboratories. Twelve laboratories returned results that were accepted to be included in the statistical evaluation. The method precision was expressed as HORRATs. For the individual toxins (except for 45-OH-YTX) HORRATs were found to be ≤1.8 (median HORRAT=0.8) in all tested materials. The recoveries of OA-, AZA- and YTX-group toxins were within the range of 80-108% and PTX2 was within the range of 62-93%. Based on the acceptable values for precision and recovery, it was concluded that the method is suitable for official control purposes to quantitatively determine OA/DTXs, AZAs, YTXs and PTX2 in shellfish.

  6. The Mechanism of Diarrhetic Shellfish Poisoning Toxin Production in Prorocentrum spp.: Physiological and Molecular Perspectives

    PubMed Central

    Lee, Thomas Chun-Hung; Fong, Fiona Long-Yan; Ho, Kin-Chung; Lee, Fred Wang-Fat

    2016-01-01

    Diarrhetic shellfish poisoning (DSP) is a gastrointestinal disorder caused by the consumption of seafood contaminated with okadaic acid (OA) and dinophysistoxins (DTXs). OA and DTXs are potent inhibitors of protein phosphatases 2A, 1B, and 2B, which may promote cancer in the human digestive system. Their expression in dinoflagellates is strongly affected by nutritional and environmental factors. Studies have indicated that the level of these biotoxins is inversely associated with the growth of dinoflagellates at low concentrations of nitrogen or phosphorus, or at extreme temperature. However, the presence of leucine or glycerophosphate enhances both growth and cellular toxin level. Moreover, the presence of ammonia and incubation in continuous darkness do not favor the toxin production. Currently, studies on the mechanism of this biotoxin production are scant. Full genome sequencing of dinoflagellates is challenging because of the massive genomic size; however, current advanced molecular and omics technologies may provide valuable insight into the biotoxin production mechanism and novel research perspectives on microalgae. This review presents a comprehensive analysis on the effects of various nutritional and physical factors on the OA and DTX production in the DSP toxin-producing Prorocentrum spp. Moreover, the applications of the current molecular technologies in the study on the mechanism of DSP toxin production are discussed. PMID:27669302

  7. Hygroscopic Behavior of Multicomponent Aerosols Involving NaCl and Dicarboxylic Acids.

    PubMed

    Peng, Chao; Jing, Bo; Guo, Yu-Cong; Zhang, Yun-Hong; Ge, Mao-Fa

    2016-02-25

    Atmospheric aerosols are usually complex mixtures of inorganic and organic compounds. The hygroscopicity of mixed particles is closely related to their chemical composition and interactions between components, which is still poorly understood. In this study, the hygroscopic properties of submicron particles composed of NaCl and dicarboxylic acids including oxalic acid (OA), malonic acid (MA), and succinic acid (SA) with various mass ratios are investigated with a hygroscopicity tandem differential mobility analyzer (HTDMA) system. Both the Zdanovskii-Stokes-Robinson (ZSR) method and extended aerosol inorganics model (E-AIM) are applied to predict the water uptake behaviors of sodium chloride/dicarboxylic acid mixtures. For NaCl/OA mixed particles, the measured growth factors were significantly lower than predictions from the model methods, indicating a change in particle composition caused by chloride depletion. The hygroscopic growth of NaCl/MA particles was well described by E-AIM, and that of NaCl/SA particles was dependent upon mixing ratio. Compared with model predictions, it was determined that water uptake of the NaCl/OA mixture could be enhanced and could be closer to the predictions by addition of levoglucosan or malonic acid, which retained water even at low relative humidity (RH), leading to inhibition of HCl evaporation during dehydration. These results demonstrate that the coexisting hygroscopic species have a strong influence on the phase state of particles, thus affecting chemical interactions between inorganic and organic compounds as well as the overall hygroscopicity of mixed particles.

  8. Serum Fatty Acids Are Correlated with Inflammatory Cytokines in Ulcerative Colitis

    PubMed Central

    Wiese, Dawn M.; Horst, Sara N.; Brown, Caroline T.; Allaman, Margaret M.; Hodges, Mallary E.; Slaughter, James C.; Druce, Jennifer P.; Beaulieu, Dawn B.; Schwartz, David A.; Wilson, Keith T.; Coburn, Lori A.

    2016-01-01

    Background and Aims Ulcerative colitis (UC) is associated with increased dietary intake of fat and n-6 polyunsaturated fatty acids (PUFA). Modification of fat metabolism may alter inflammation and disease severity. Our aim was to assess differences in dietary and serum fatty acid levels between control and UC subjects and associations with disease activity and inflammatory cytokines. Methods Dietary histories, serum, and colonic tissue samples were prospectively collected from 137 UC subjects and 38 controls. Both histologic injury and the Mayo Disease Activity Index were assessed. Serum and tissue cytokines were measured by Luminex assay. Serum fatty acids were obtained by gas chromatography. Results UC subjects had increased total fat and oleic acid (OA) intake, but decreased arachidonic acid (AA) intake vs controls. In serum, there was less percent saturated fatty acid (SFA) and AA, with higher monounsaturated fatty acids (MUFA), linoleic acid, OA, eicosapentaenoic acid (EPA), and docosapentaenoic acid (DPA) in UC. Tissue cytokine levels were directly correlated with SFA and inversely correlated with PUFA, EPA, and DPA in UC subjects, but not controls. 5-aminosalicylic acid therapy blunted these associations. Conclusions In summary, we found differences in serum fatty acids in UC subjects that correlated with pro-inflammatory tissue cytokines. We propose that fatty acids may affect cytokine production and thus be immunomodulatory in UC. PMID:27227540

  9. Feasibility randomised controlled trial of Recovery-focused Cognitive Behavioural Therapy for Older Adults with bipolar disorder (RfCBT-OA): study protocol

    PubMed Central

    Tyler, Elizabeth; Lobban, Fiona; Sutton, Chris; Depp, Colin; Johnson, Sheri; Laidlaw, Ken; Jones, Steven H

    2016-01-01

    Introduction Bipolar disorder is a severe and chronic mental health problem that persists into older adulthood. The number of people living with this condition is set to rise as the UK experiences a rapid ageing of its population. To date, there has been very little research or service development with respect to psychological therapies for this group of people. Methods and analysis A parallel two-arm randomised controlled trial comparing a 14-session, 6-month Recovery-focused Cognitive-Behavioural Therapy for Older Adults with bipolar disorder (RfCBT-OA) plus treatment as usual (TAU) versus TAU alone. Participants will be recruited in the North-West of England via primary and secondary mental health services and through self-referral. The primary objective of the study is to evaluate the feasibility and acceptability of RfCBT-OA; therefore, a formal power calculation is not appropriate. It has been estimated that randomising 25 participants per group will be sufficient to be able to reliably determine the primary feasibility outcomes (eg, recruitment and retention rates), in line with recommendations for sample sizes for feasibility/pilot trials. Participants in both arms will complete assessments at baseline and then every 3 months, over the 12-month follow-up period. We will gain an estimate of the likely effect size of RfCBT-OA on a range of clinical outcomes and estimate parameters needed to determine the appropriate sample size for a definitive, larger trial to evaluate the effectiveness and cost-effectiveness of RfCBT-OA. Data analysis is discussed further in the Analysis section in the main paper. Ethics and dissemination This protocol was approved by the UK National Health Service (NHS) Ethics Committee process (REC ref: 15/NW/0330). The findings of the trial will be disseminated through peer-reviewed journals, national and international conference presentations and local, participating NHS trusts. Trial registration number ISRCTN13875321; Pre

  10. Complete Genome Sequence of the Multiresistant Acinetobacter baumannii Strain AbH12O-A2, Isolated during a Large Outbreak in Spain

    PubMed Central

    Merino, M.; Alvarez-Fraga, L.; Gómez, M. J.; Aransay, A. M.; Lavín, J. L.; Chaves, F.

    2014-01-01

    We report the complete genome sequence of Acinetobacter baumannii strain AbH12O-A2, isolated during a large outbreak in Spain. The genome has 3,875,775 bp and 3,526 coding sequences, with 39.4% G+C content. The availability of this genome will facilitate the study of the pathogenicity of the Acinetobacter species. PMID:25395646

  11. An Oleate Hydroxylase from the Fungus Claviceps purpurea: Cloning, Functional Analysis, and Expression in Arabidopsis[OA

    PubMed Central

    Meesapyodsuk, Dauenpen; Qiu, Xiao

    2008-01-01

    Claviceps purpurea, a fungal pathogen responsible for ergot diseases in many agriculturally important cereal crops, produces high levels of ricinoleic acid (12-hydroxyoctadec-cis-9-enoic acid) in its sclerotia. It has been believed for many years that the biosynthesis of this fatty acid in C. purpurea involves a hydration process with linoleic acid as the substrate. Using degenerate polymerase chain reaction, we cloned a gene from the sclerotia encoding an enzyme (CpFAH) that has high sequence similarity to the C. purpurea oleate desaturase, but only low similarity to plant oleate hydroxylases. Functional analysis of CpFAH in yeast (Saccharomyces cerevisiae) indicated it acted predominantly as a hydroxylase, introducing hydroxyl groups at the 12-position of oleic acid and palmitoleic acid. As well, it showed Δ12 desaturase activities on 16C and 18C monounsaturated fatty acids and, to a much lesser extent, ω3 desaturase activities on ricinoleic acid. Heterologous expression of CpFAH under the guidance of a seed-specific promoter in Arabidopsis (Arabidopsis thaliana) wild-type and mutant (fad2/fae1) plants resulted in the accumulation of relatively higher levels of hydroxyl fatty acids in seeds. These data indicate that the biosynthesis of ricinoleic acid in C. purpurea is catalyzed by the fungal desaturase-like hydroxylase, and CpFAH, the first Δ12 oleate hydroxylase of nonplant origin, is a good candidate for the transgenic production of hydroxyl fatty acids in oilseed crops. PMID:18467452

  12. The hematopoietic regulator, ELF-1, enhances the transcriptional response to Interferon-β of the OAS1 anti-viral gene.

    PubMed

    Larsen, Steven; Kawamoto, Shota; Tanuma, Sei-ichi; Uchiumi, Fumiaki

    2015-12-08

    Interferon (IFN) therapy is effective in treating cancers, haematological and virus induced diseases. The classical Jak/Stat pathway of IFN signal transduction leading to changes in transcriptional activity is well established but alone does not explain the whole spectrum of cellular responses to IFN. Gene promoters contain cis-acting sequences that allow precise and contextual binding of transcription factors, which control gene expression. Using the transcriptional response to IFN as a starting point we report a high frequency of tandem GGAA motifs in the proximal promoters of Interferon stimulated genes, suggesting a key regulatory action. Utilizing the well-characterized anti-viral gene, OAS1, as an example Interferon stimulated gene promoter containing such a duplicated GGAA motif, we have demonstrated a regulatory role of this promoter in response to IFN by mutation analysis. Furthermore, we identified ELF-1 as a direct binding factor at this motif. Additionally, recruitment of RB1 and SP1 factors to the promoter following IFN stimulation is shown. ELF-1 overexpression enhanced and knockdown of ELF-1 inhibited full activation of OAS1 by IFN stimulation. Collectively, ELF-1 binds an important duplicated GGAA cis-acting element at the OAS1 promoter and in cooperation with RB1 and SP1 recruitment contributes to regulation in response to IFN stimulation.

  13. Roles of OA1 octopamine receptor and Dop1 dopamine receptor in mediating appetitive and aversive reinforcement revealed by RNAi studies.

    PubMed

    Awata, Hiroko; Wakuda, Ryo; Ishimaru, Yoshiyasu; Matsuoka, Yuji; Terao, Kanta; Katata, Satomi; Matsumoto, Yukihisa; Hamanaka, Yoshitaka; Noji, Sumihare; Mito, Taro; Mizunami, Makoto

    2016-07-14

    Revealing reinforcing mechanisms in associative learning is important for elucidation of brain mechanisms of behavior. In mammals, dopamine neurons are thought to mediate both appetitive and aversive reinforcement signals. Studies using transgenic fruit-flies suggested that dopamine neurons mediate both appetitive and aversive reinforcements, through the Dop1 dopamine receptor, but our studies using octopamine and dopamine receptor antagonists and using Dop1 knockout crickets suggested that octopamine neurons mediate appetitive reinforcement and dopamine neurons mediate aversive reinforcement in associative learning in crickets. To fully resolve this issue, we examined the effects of silencing of expression of genes that code the OA1 octopamine receptor and Dop1 and Dop2 dopamine receptors by RNAi in crickets. OA1-silenced crickets exhibited impairment in appetitive learning with water but not in aversive learning with sodium chloride solution, while Dop1-silenced crickets exhibited impairment in aversive learning but not in appetitive learning. Dop2-silenced crickets showed normal scores in both appetitive learning and aversive learning. The results indicate that octopamine neurons mediate appetitive reinforcement via OA1 and that dopamine neurons mediate aversive reinforcement via Dop1 in crickets, providing decisive evidence that neurotransmitters and receptors that mediate appetitive reinforcement indeed differ among different species of insects.

  14. Roles of OA1 octopamine receptor and Dop1 dopamine receptor in mediating appetitive and aversive reinforcement revealed by RNAi studies

    PubMed Central

    Awata, Hiroko; Wakuda, Ryo; Ishimaru, Yoshiyasu; Matsuoka, Yuji; Terao, Kanta; Katata, Satomi; Matsumoto, Yukihisa; Hamanaka, Yoshitaka; Noji, Sumihare; Mito, Taro; Mizunami, Makoto

    2016-01-01

    Revealing reinforcing mechanisms in associative learning is important for elucidation of brain mechanisms of behavior. In mammals, dopamine neurons are thought to mediate both appetitive and aversive reinforcement signals. Studies using transgenic fruit-flies suggested that dopamine neurons mediate both appetitive and aversive reinforcements, through the Dop1 dopamine receptor, but our studies using octopamine and dopamine receptor antagonists and using Dop1 knockout crickets suggested that octopamine neurons mediate appetitive reinforcement and dopamine neurons mediate aversive reinforcement in associative learning in crickets. To fully resolve this issue, we examined the effects of silencing of expression of genes that code the OA1 octopamine receptor and Dop1 and Dop2 dopamine receptors by RNAi in crickets. OA1-silenced crickets exhibited impairment in appetitive learning with water but not in aversive learning with sodium chloride solution, while Dop1-silenced crickets exhibited impairment in aversive learning but not in appetitive learning. Dop2-silenced crickets showed normal scores in both appetitive learning and aversive learning. The results indicate that octopamine neurons mediate appetitive reinforcement via OA1 and that dopamine neurons mediate aversive reinforcement via Dop1 in crickets, providing decisive evidence that neurotransmitters and receptors that mediate appetitive reinforcement indeed differ among different species of insects. PMID:27412401

  15. Oleanolic acid inhibits proliferation and induces apoptosis in NB4 cells by targeting PML/RARα

    PubMed

    Li, Hongmei; He, Ning; Li, Xueyan; Zhou, Li; Zhao, Mingyu; Jiang, Hairui; Zhang, Xiaojie

    2013-10-01

    Oleanolic acid (OA), a naturally occurring pentacyclic triterpenoid contained in a variety of plant species, exhibits broad biological properties, including anticancer effects. Acute promyelocytic leukemia (APL) is a distinct subtype of acute myeloid leukemia. APL has a unique and specific chromosomal aberration, t(15;17), which results in the formation of a fusion gene and protein PML/RARα, which is not only necessary for the diagnosis of APL, but is also critical for APL pathogenesis. In the present study, the cytotoxic effect of OA on NB4 cells was investigated. Cell viability was assessed via the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The expression levels of bax and bcl-2 mRNA were determined by quantitative PCR. Apoptosis was analyzed using DNA fragment analysis and cell cycle distributions were analyzed by flow cytometry. The activity of caspase-3 and caspase-9 was determined by colorimetric assays. The expression of the PML/RARα fusion protein was analyzed by western blotting. The MTT assay showed that OA inhibited the proliferation of the NB4 cells. The expression levels of pro-apoptotic bax mRNA were increased and the levels of anti-apoptotic bcl-2 mRNA were decreased following the treatment of the NB4 cells with OA at 80 μmol/l. Treatment of the NB4 cells with OA at 80 μmol/l induced apoptosis and G1 phase arrest, while caspase-9 and caspase-3 activity was significantly increased. Furthermore, the expression of the PML/RARα fusion protein was decreased. Together, these data suggest that OA exerts a cytotoxic effect that inhibits proliferation and induces apoptosis in NB4 cells by targeting PML/RARα, making it a potent therapeutic agent against leukemia.

  16. Geochronology of the Neogene intrusive magmatism of the Oaș—Gutâi Mountains, Eastern Carpathians (NW Romania)

    NASA Astrophysics Data System (ADS)

    Kovacs, Marinel; Pécskay, Zoltán; Fülöp, Alexandrina; Jurje, Maria; Edelstein, Oscar

    2013-12-01

    Earlier geological work in the Oaș-Gutâi Mts (OG), Eastern Carpathians, has revealed the extensive presence of shallow subvolcanic intrusive bodies, both exposed on the surface and covered by Paleogene-Neogene sedimentary sequences and Neogene volcanic formations. This study is based on detailed mapping and sampling of the OG Neogene intrusive magmatic rocks. Thirty seven representative intrusions (sills, dykes, microlaccoliths, etc.) were selected for radiometric dating. These intrusions show a wide variety of petrographic rock-types: from microgabbros to microgranodiorites and from basalts to andesites. However, the intrusions consist of typical calc-alkaline, medium-K rocks, similar to the volcanic rocks which outcrop in the same areas. The K-Ar age determinations on whole-rock samples of intrusions yielded ages between 11.9 Ma and 7.0 Ma (from Late Sarmatian to Middle Pannonian). The results are in good agreement with the common assumption, based on the biostratigraphic and geological data, that large volumes of intrusions have formed during the paroxysm of the intermediate volcanic activity in the OG. Except for the Firiza basalt intrusive complex of the Gutâi Mts (8.1-7.0 Ma), the OG intrusions show similar K-Ar ages as the intrusions of the "Subvolcanic Zone" and Călimani Mts from Eastern Carpathians. The timing of the OG intrusive magmatism partially overlaps with the timing of the intrusive magmatic activity in the Eastern Moravia and Pieniny Mts. The systematic radiometric datings in the whole OG give clear evidence that the hydrothermal activity related to the epithermal systems always postdates intrusion emplacement.

  17. Antitumor Agents 255. Novel Glycyrrhetinic Acid-Dehydrozingerone Conjugates as Cytotoxic Agents

    PubMed Central

    Tatsuzaki, Jin; Taniguchi, Masahiko; Bastow, Kenneth F.; Nakagawa-Goto, Kyoko; Morris-Natschke, Susan L.; Itokawa, Hideji; Baba, Kimiye; Lee, Kuo-Hsiung

    2007-01-01

    Esterification of glycyrrhetinic acid (GA) with dehydrozingerone (DZ) resulted in a novel cytotoxic GA-DZ conjugate. Based on this exciting finding, we conjugated eleven different DZ analogs with GA or other triterpenoids, including oleanoic acid (OA) or ursolic acid (UA). In an in vitro anticancer assay using nine different human tumor cell lines, most of the GA-DZ conjugates showed significant potency. Particularly, compounds 5, 29, and 30 showed significant cytotoxic effects against LN-Cap, 1A9, and KB cells with ED50 values of 0.6, 0.8, and 0.9 μM, respectively. Similar conjugates between DZ and OA or UA were inactive suggesting that the GA component is critical for activity. Notably, although GA-DZ conjugates showed potent cytotoxic activity, the individual components (GA and DZ analogs) were inactive. Thus, GA-DZ conjugates are new chemical entities and represent interesting hits for anticancer drug discovery and development. PMID:17591444

  18. Hyaluronic acid attenuates osteoarthritis development in the anterior cruciate ligament-transected knee: Association with excitatory amino acid release in the joint dialysate.

    PubMed

    Jean, Yen-Hsuan; Wen, Zhi-Hong; Chang, Yi-Chen; Lee, Herng-Sheng; Hsieh, Shih-Peng; Wu, Ching-Tang; Yeh, Chun-Chang; Wong, Chih-Shung

    2006-05-01

    We previously reported increased release of the excitatory amino acid (EAA) neurotransmitters, glutamate and aspartate, during the early stage of experimental osteoarthritis (OA). Our present objective was to study the effect of intraarticular injection of hyaluronic acid (HA) on OA development, and to analyze concomitant changes in EAA levels in dialysates of anterior cruciate ligament-transected (ACLT) knee joints. OA was induced in Wistar rats by ACLT of one hindlimb; the knee of the other hindlimb was used as the sham-operated control. HA group (n = 12) were injected intraarticularly in the ACLT knee with 1 mg of HA once a week for 5 consecutive weeks, starting at 8 weeks after surgery. Saline group (n = 12) were injected as above with normal saline. The sham-operated group, underwent arthrotomy, but not ACLT, and received no treatment (n = 14). Twenty weeks after surgery, knee joint dialysates were collected by microdialysis and EAA levels assayed by high-performance liquid chromatography, and gross morphological examination and histopathological evaluation were performed on the medial femoral condyles and synovia. Rats receiving intraarticular HA injections showed a significantly lower degree of cartilage degeneration on the medial femoral condyle at both the macroscopic level and on the Mankin grading scale than rats receiving saline injections. Intraarticular HA treatment also suppressed synovitis. Moreover, glutamate and aspartate levels were significantly reduced in the HA group compared to the saline group. Intraarticular injection of HA limits articular cartilage and synovium damage and OA formation, and, in parallel, reduces EAA levels in ACLT joint dialysates. This study suggests that the underlying mechanism of the anti-inflammatory effect of HA is to inhibit glutamate and aspartate release in ACLT knee joints, which attenuates the early development of OA.

  19. Effect of eicosapentaenoic acid ethyl ester v. oleic acid-rich safflower oil on insulin resistance in type 2 diabetic model rats with hypertriacylglycerolaemia.

    PubMed

    Minami, Asako; Ishimura, Noriko; Sakamoto, Sadaichi; Takishita, Eiko; Mawatari, Kazuaki; Okada, Kazuko; Nakaya, Yutaka

    2002-02-01

    The purpose of the present study was to test whether hyperlipidaemia and insulin resistance in type 2 diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats can be improved by dietary supplementation with purified eicosapentaenoic acid (EPA) or oleic acid (OA). Male OLETF rats were fed powdered chow (510 g fat/kg) alone (n 8) or chow supplemented with 10 g EPA- (n 8) or OA- (n 8) rich oil/kg per d from 5 weeks until 30 weeks of age. An oral glucose tolerance test and hyperinsulinaemic euglycaemic clamp was performed at 25 and 30 weeks of age. EPA supplementation resulted in significantly (P<0.05) reduced plasma lipids, hepatic triacylglycerols, and abdominal fat deposits, and more efficient in vivo glucose disposal compared with OA supplementation and no supplementation. OA supplementation was associated with significantly increased insulin response to oral glucose compared with EPA supplementation and no supplementation. Inverse correlation was noted between glucose uptake and plasma triacylglycerol levels (r -086, P<0.001) and abdominal fat volume (r -0.80, P<0.001). The result of oral glucose tolerance test study showed that the rats fed EPA tended to improve glucose intolerance, although this was not statistically significant. Levels of plasma insulin at 60 min after glucose was significantly increased in rats fed OA compared with the other two groups. The results indicate that long-term feeding of EPA might be effective in preventing insulin resistance in diabetes-prone rats, at least in part, due to improving hypertriacylglycerolaemia.

  20. Okadaic acid mediates p53 hyperphosphorylation and growth arrest in cells with wild-type p53 but increases aberrant mitoses in cells with non-functional p53.

    PubMed

    Milczarek, G J; Chen, W; Gupta, A; Martinez, J D; Bowden, G T

    1999-06-01

    The protein phosphatase inhibitor and tumor promoting agent okadaic acid (OA), has been shown previously to induce hyperphosphorylation of p53 protein, which in turn correlated with increased transactivation or apoptotic function. However, how the tumor promotion effects of OA relate to p53 tumor supressor function (or dysfunction) remain unclear. Rat embryonic fibroblasts harboring a temperature-sensitive mouse p53 transgene were treated with 50 nM doses of OA. At the wild-type permissive temperature this treatment resulted in: (i) the hyperphosphorylation of sites within tryptic peptides of the transactivation domain of p53; (ii) an increase in p53 affinity for a p21(waf1) promotor oligonucleotide; (iii) an increase in cellular steady state levels of p21(waf1) message; (iv) a G2/M cell cycle blockage in addition to the G1/S arrest previously associated with p53; and (v) no increased incidence of apoptosis. On the other hand, OA treatment at the mutated p53 permissive temperature resulted in a relatively high incidence of aberrant mitosis with no upregulation of p21(waf1) message. These results suggest that while wild-type p53 blocks the proliferative effects of OA through p21(waf1)-mediated growth arrest, cells with non-functional p53 cannot arrest and suffer relatively high levels of OA-mediated aberrant mitoses.

  1. Selection and identification of DNA aptamers against okadaic acid for biosensing application.

    PubMed

    Eissa, Shimaa; Ng, Andy; Siaj, Mohamed; Tavares, Ana C; Zourob, Mohammed

    2013-12-17

    This work describes the selection and identification of DNA aptamers that bind with high affinity and specificity to okadaic acid (OA), a lipophilic marine biotoxin that accumulates in shellfish. The aptamers selected using systematic evolution of ligands by exponential enrichment (SELEX) exhibited dissociation constants in the nanomolar range. The aptamer with the highest affinity was then used for the fabrication of a label-free electrochemical biosensor for okadaic acid detection. The aptamer was first immobilized on the gold electrode by a self-assembly approach through Au-S interaction. The binding of okadaic acid to the aptamer immobilized on the electrode surface induces an alteration of the aptamer conformation causing a significant decrease in the electron-transfer resistance monitored by electrochemical impedance spectroscopy. The aptasensor showed a linear range for the concentrations of OA between 100 pg/mL and 60 ng/mL with a detection limit of 70 pg/mL. The dissociation constant of okadaic acid with the aptamer immobilized on the electrode surface showed good agreement with that determined using fluorescence assay in solution. Moreover, the aptasensor did not show cross-reactivity toward toxins with structures similar to okadaic acid such as dinophysis toxin-1 and 2 (DTX-1, DTX-2). Further biosensing applications of the selected aptamers are expected to offer promising alternatives to the traditional analytical and immunological methods for OA detection.

  2. Fate of orally administered radioactive fatty acids in the late-pregnant rat.

    PubMed

    López-Luna, Pilar; Ortega-Senovilla, Henar; López-Soldado, Iliana; Herrera, Emilio

    2016-03-01

    To investigate the biodisponibility of placental transfer of fatty acids, rats pregnant for 20 days were given tracer amounts of [(14)C]palmitic (PA), oleic (OA), linoleic (LA), α-linolenic (LNA), or docosahexaenoic acid (DHA) orally and euthanized at 0.5, 1.0, 2.0, or 8.0 h thereafter. Maternal plasma radioactivity in lipids initially increased only to decline at later times. Most of the label appeared first as triacylglycerols (TAG); later, the proportion in phospholipids (PhL) increased. The percentage of label in placental lipids was also always highest shortly after administration and declined later; again, PhL increased with time. Fetal plasma radioactivity increased with time, with its highest value at 8.0 h after DHA or LNA administration. DHA initially appeared primarily in the nonesterified fatty acids (NEFA) and PA, OA, LA, and LNA as TAG followed by NEFA; in all cases, there was an increase in PhL at later times. Measurement of fatty acid concentrations allowed calculation of specific (radio)activities, and the ratio (fetal/maternal) of these in the plasmas gave an index of placental transfer activity, which was LNA > LA > DHA = OA > PA. It is proposed that a considerable proportion of most fatty acids transferred through the placenta are released into the fetal circulation in the form of TAG.

  3. Understanding the effect low molecular weight organic acids on the desorption and availability of soil phosphorus

    NASA Astrophysics Data System (ADS)

    Blackburn, Daniel; Zhang, Hao; Stutter, Marc; Giles, Courtney; George, Timothy; Shand, Charles; Lumsdon, David; Cooper, Pat; Wendler, Renate; Brown, Lawrie; Blackwell, Martin; Darch, Tegan; Wearing, Catherine; Haygarth, Philip

    2016-04-01

    The mobility and resupply of inorganic phosphorus (P) from the soil solid phase after equilibration with increasing doses of citric acid (CA) and oxalic acid (OA) were studied in 2 soils with contrasting P status. The combined methods of diffusive gradients in thin films (DGT), diffusive equilibration in thin films (DET) and the DGT-induced fluxes in sediments model (DIFS) were used as tools to evaluate the changes in solid-to-solution interchange kinetics. A significant effect of CA and OA in soil solution P was observed only for doses over 1 mMol kg-1. Curiously, low organic acid doses (0.5-1 mMol kg-1) were associated with a steep increase in microbial biomass P, which was not seen for doses over 2 mMol kg-1. The trivalent CA was able to promote a higher increase in soil solution P than the bivalent OA for both soils. Organic phosphorus was only significantly mobilized by organic acids in the low P soil, possibly because in the high P soil these P forms were less labile than inorganic P. Both CA and OA promoted a decrease in the adsorbed-to-solution distribution coefficient, desorption rate constants and an increase in the response time of solution P equilibration. The extent of this effect was shown to be both soil specific and organic acid specific. Since both organic acids negatively affected the kinetics of P interchange between the soil matrix and the soil solution, their net effect on P bioavailability is expected to be much lower than the observed increase in solution concentration.

  4. OA Go Away: Development and Preliminary Validation of a Self-Management Tool to Promote Adherence to Exercise and Physical Activity for People with Osteoarthritis of the Hip or Knee.

    PubMed

    Paterson, Gail; Toupin April, Karine; Backman, Catherine; Tugwell, Peter

    2016-01-01

    Purpose: To determine the face and content validity, construct validity, and test-retest reliability of the OA Go Away (OGA), a personalized self-management tool to promote adherence to exercise and physical activity for people with osteoarthritis (OA) of the hip or knee. Methods: The face and content validity of OGA version 1.0 were determined via interviews with 10 people with OA of the hip or knee and 10 clinicians. A revised OGA version 2.0 was then tested for construct validity and test-retest reliability with a new sample of 50 people with OA of the hip or knee by comparing key items in the OGA journal with validated outcome measures assessing similar health outcomes and comparing scores on key items of the journal 4-7 days apart. Face and content validity were then confirmed with a new sample of 5 people with OA of the hip or knee and 5 clinicians. Results: Eighteen of 30 items from the OGA version 1.0 and 41 of 43 items from the OGA version 2.0 journal, goals and action plan, and exercise log had adequate content validity. Construct validity and test-retest reliability were acceptable for the main items of the OGA version 2.0 journal. The OGA underwent modifications based on results and participant feedback. Conclusion: The OGA is a novel self-management intervention and assessment tool for people with OA of the hip or knee that shows adequate preliminary measurement properties.

  5. Nitro-fatty acid pharmacokinetics in the adipose tissue compartment.

    PubMed

    Fazzari, Marco; Khoo, Nicholas K H; Woodcock, Steven R; Jorkasky, Diane K; Li, Lihua; Schopfer, Francisco J; Freeman, Bruce A

    2017-02-01

    Electrophilic nitro-FAs (NO2-FAs) promote adaptive and anti-inflammatory cell signaling responses as a result of an electrophilic character that supports posttranslational protein modifications. A unique pharmacokinetic profile is expected for NO2-FAs because of an ability to undergo reversible reactions including Michael addition with cysteine-containing proteins and esterification into complex lipids. Herein, we report via quantitative whole-body autoradiography analysis of rats gavaged with radiolabeled 10-nitro-[(14)C]oleic acid, preferential accumulation in adipose tissue over 2 weeks. To better define the metabolism and incorporation of NO2-FAs and their metabolites in adipose tissue lipids, adipocyte cultures were supplemented with 10-nitro-oleic acid (10-NO2-OA), nitro-stearic acid, nitro-conjugated linoleic acid, and nitro-linolenic acid. Then, quantitative HPLC-MS/MS analysis was performed on adipocyte neutral and polar lipid fractions, both before and after acid hydrolysis of esterified FAs. NO2-FAs preferentially incorporated in monoacyl- and diacylglycerides, while reduced metabolites were highly enriched in triacylglycerides. This differential distribution profile was confirmed in vivo in the adipose tissue of NO2-OA-treated mice. This pattern of NO2-FA deposition lends new insight into the unique pharmacokinetics and pharmacologic actions that could be expected for this chemically-reactive class of endogenous signaling mediators and synthetic drug candidates.

  6. Separation of aliphatic carboxylic acids and benzenecarboxylic acids by ion-exclusion chromatography with various cation-exchange resin columns and sulfuric acid as eluent.

    PubMed

    Ohta, Kazutoku; Ohashi, Masayoshi; Jin, Ji-Ye; Takeuchi, Toyohide; Fujimoto, Chuzo; Choi, Seong-Ho; Ryoo, Jae-Jeong; Lee, Kwang-Pill

    2003-05-16

    The application of various hydrophilic cation-exchange resins for high-performance liquid chromatography (sulfonated silica gel: TSKgel SP-2SW, carboxylated silica gel: TSKgel CM-2SW, sulfonated polymethacrylate resin: TSKgel SP-5PW, carboxylated polymethacrylate resins: TSKgel CM-5PW and TSKgel OA-Pak A) as stationary phases in ion-exclusion chromatography for C1-C7 aliphatic carboxylic acids (formic, acetic, propionic, butyric, isovaleric, valeric, isocaproic, caproic, 2-methylhexanoic and heptanoic acids) and benzenecarboxylic acids (pyromellitic, trimellitic, hemimellitic, o-phthalic, m-phthalic, p-phthalic, benzoic, salicylic acids and phenol) was carried out using diluted sulfuric acid as the eluent. Silica-based cation-exchange resins (TSKgel SP-2SW and TSKgel CM-2SW) were very suitable for the ion-exclusion chromatographic separation of these benzenecarboxylic acids. Excellent simultaneous separation of these benzenecarboxylic acids was achieved on a TSKgel SP-2SW column (150 x 6 mm I.D.) in 17 min using a 2.5 mM sulfuric acid at pH 2.4 as the eluent. Polymethacrylate-based cation-exchange resins (TSKgel SP-5PW, TSKgel CM-5PW and TSKgel OA-Pak A) acted as advanced stationary phases for the ion-exclusion chromatographic separation of these C1-C7 aliphatic carboxylic acids. Excellent simultaneous separation of these C1-C7 acids was achieved on a TSKgel CM-5PW column (150 x 6 mm I.D.) in 32 min using a 0.05 mM sulfuric acid at pH 4.0 as the eluent.

  7. Determination of oleanolic acid, ursolic acid and amygdalin in the flower of Eriobotrya japonica Lindl. by HPLC.

    PubMed

    Zhou, Chunhua; Chen, Kunsong; Sun, Chongde; Chen, Qingjun; Zhang, Wangshu; Li, Xian

    2007-07-01

    Simple and accurate HPLC methods were developed for the determination of oleanolic acid (OA), ursolic acid (UA) and amygdalin in loquat (Eriobotrya japonica Lindl.) flower, which is commonly used for the treatment of various diseases as a traditional Chinese medicine. HPLC assay was performed on a reversed-phase C(18) column and all three compounds were detected at 210 nm with a flow rate of 1.0 mL/min. The mobile phase consisted of methanol (A) and 0.03 mol/L phosphate buffer (pH 2.8) (B) with a ratio of 88:12 (A:B, v/v) for simultaneous detection of OA and UA, and 25:75 (A:B, v/v) for detection of amygdalin. The established methods showed good precision and accuracy with overall intra-day and inter-day variation of 0.99-3.55 and 1.05-4.05%, respectively, and overall recoveries of 97.37-99.32% for the three compounds. Application of these methods to determine the OA, UA and amygdalin contents in loquat flower showed that cultivar had a minor effect on the contents of all three compounds, with average amounts of 0.38-0.51 mg OA/g dry weight (DW), 2.15-2.68 mg UA/g DW and 1.23-1.56 mg amygdalin/g DW among five loquat cultivars tested. However, developmental stages and flower tissues showed significant effect on the contents of all three bioactive components.

  8. A solvent extraction approach to recover acetic acid from mixed waste acids produced during semiconductor wafer process.

    PubMed

    Shin, Chang-Hoon; Kim, Ju-Yup; Kim, Jun-Young; Kim, Hyun-Sang; Lee, Hyang-Sook; Mohapatra, Debasish; Ahn, Jae-Woo; Ahn, Jong-Gwan; Bae, Wookeun

    2009-03-15

    Recovery of acetic acid (HAc) from the waste etching solution discharged from silicon wafer manufacturing process has been attempted by using solvent extraction process. For this purpose 2-ethylhexyl alcohol (EHA) was used as organic solvent. In the pre-treatment stage >99% silicon and hydrofluoric acid was removed from the solution by precipitation. The synthesized product, Na(2)SiF(6) having 98.2% purity was considered of commercial grade having good market value. The waste solution containing 279 g/L acetic acid, 513 g/L nitric acid, 0.9 g/L hydrofluoric acid and 0.030 g/L silicon was used for solvent extraction study. From the batch test results equilibrium conditions for HAc recovery were optimized and found to be 4 stages of extraction at an organic:aqueous (O:A) ratio of 3, 4 stages of scrubbing and 4 stages of stripping at an O:A ratio of 1. Deionized water (DW) was used as stripping agent to elute HAc from organic phase. In the whole batch process 96.3% acetic acid recovery was achieved. Continuous operations were successfully conducted for 100 h using a mixer-settler to examine the feasibility of the extraction system for its possible commercial application. Finally, a complete process flowsheet with material balance for the separation and recovery of HAc has been proposed.

  9. Oleanolic acid, a natural triterpenoid improves blood glucose tolerance in normal mice and ameliorates visceral obesity in mice fed a high-fat diet.

    PubMed

    de Melo, Célio L; Queiroz, Maria Goretti R; Fonseca, Said G C; Bizerra, Ayla M C; Lemos, Telma L G; Melo, Tiago S; Santos, Flavia A; Rao, Vietla S

    2010-04-15

    Excess visceral adiposity may predispose to chronic diseases like hypertension and type 2 diabetes with a high risk for coronary artery disease. Adipose tissue secreted cytokines and oxidative stress play an important role in chronic disease progression. To combat adiposity, plant-derived triterpenes are currently receiving much attention as they possess antioxidant and anti-inflammatory properties and the ability to regulate glucose and lipid metabolism. In the search for potential antiobese compounds from natural sources, this study evaluated the effects of oleanolic acid (OA), a pentacyclic triterpene commonly present in fruits and vegetables, in glucose tolerance test and on high-fat diet (HFD)-induced obesity in mice. Adult male Swiss mice treated or not with OA (10 mg/kg) were fed a HFD during 15 weeks. Sibutramine (SIB) treated group (10 mg/kg) was included for comparison. Weekly body weights, food and water consumption were measured, and at the end of study period, the levels of blood glucose and lipids, plasma hormone levels of insulin, ghrelin and leptin, and the visceral abdominal fat content were analysed. Mice treated with OA and fed a HFD showed significantly (p<0.05) improved glucose tolerance, decreased body weights, visceral adiposity, blood glucose, plasma lipids relative to their respective controls fed no OA. Additionally, OA treatment, while significantly elevating the plasma hormone level of leptin, decreased the level of ghrelin. However, it caused a greater decrease in plasma amylase activity than lipase. Sibutramine-treated group also manifested similar effects like OA except for blood glucose level that was not different from HFD control. These findings suggest that OA ameliorates visceral adiposity and improves glucose tolerance in mice and thus has an antiobese potential through modulation of carbohydrate and fat metabolism.

  10. Identification of cellular genes induced in human cells after activation of the OAS/RNaseL pathway by vaccinia virus recombinants expressing these antiviral enzymes.

    PubMed

    Domingo-Gil, Elena; González, José Manuel; Esteban, Mariano

    2010-03-01

    Interferon (IFN) type I induces the expression of antiviral proteins such as 2',5'-oligoadenylate synthetases (OAS). The enzyme OAS is activated by dsRNA to produce 5'-phosphorylated, 2-5-linked oligoadenylates (2-5A) that activate RNaseL which, in turn, triggers RNA breakdown, leading to multiple biological functions. Although RNaseL is required for IFN antiviral function, there are many aspects of the molecular mechanisms that remain obscure. Here, we have used microarray analyses from human HeLa cells infected with vaccinia virus (VACV) recombinants expressing OAS-RNaseL enzymes (referred as 2-5A system) with the aim to identify host genes that are up- or down-regulated in the course of infection by the activation of this antiviral pathway. We found that activation of the 2-5A system from VACV recombinants produces a remarkable stimulation of transcription for genes that regulate many cellular processes, like those that promote cell growth arrest, GADD45B and KCTD11, apoptosis as CUL2, PDCD6, and TNFAIP8L2, IFN-stimulated genes as IFI6, and related to tumor suppression as PLA2G2A. The 2-5A system activation produces down-regulation of transcription of some genes that promote cell growth as RUNX2 and ESR2 and of genes in charge to maintain mitochondria homeostasis as MIPEP and COX5A. These results reveal new genes induced in response to the activation of the 2-5A system with roles in apoptosis, translational control, cell growth arrest, and tumor suppression.

  11. Polymorphisms in interferon-induced genes and the outcome of hepatitis C virus infection: roles of MxA, OAS-1 and PKR.

    PubMed

    Knapp, S; Yee, L J; Frodsham, A J; Hennig, B J W; Hellier, S; Zhang, L; Wright, M; Chiaramonte, M; Graves, M; Thomas, H C; Hill, A V S; Thursz, M R

    2003-09-01

    Interferon stimulates the expression of a number of genes encoding enzymes with antiviral activities, including myxovirus resistance-1 (MxA), 2-5-oligoadenylate synthetase 1 (OAS-1) and double-stranded RNA-dependent protein kinase (PKR). We examined whether polymorphisms in these genes influenced the outcome of hepatitis C virus (HCV) infection. We observed a lower frequency of the GG genotype at position -88 in the MxA gene promoter in self-limiting HCV infection (OR=0.56; 95% CI: 0.35-0.8; P=0.010) and in nonresponders to therapy (OR=0.49; 95% CI: 0.25-0.95; P=0.020). This genotype predominantly influenced the outcome of treatment in patients with viral genotype 1 (OR=0.22 95% CI: 0.07-0.67; P=0.002). A polymorphism in the 3'-untranslated region of the OAS-1 gene was associated with outcome of infection (GG genotype less frequent in self-limiting infection: OR=0.43; 95% CI: 0.21-0.86; P=0.010). A polymorphism at position -168 in the promoter region of the PKR gene was associated with self-limiting infection (CT genotype: OR=2.75; 95% CI: 1.45-5.24; P=0.002). Further associations were found with a CGG trinucleotide repeat in the 5'UTR region of the PKR gene. Polymorphisms in the interferon-induced genes, MxA, OAS-1 and PKR appear thus associated with HCV outcome.

  12. Comparative study of electroless nickel film on different organic acids modified cuprammonium fabric (CF)

    NASA Astrophysics Data System (ADS)

    Zhao, Hang; Lu, Yinxiang

    2016-01-01

    Nickel films were grown on citric acid (CA), malic acid (MA) and oxalic acid (OA) modified cuprammonium fabric (CF) substrates via electroless nickel deposition. The nickel films were examined using scanning electron microscopy (SEM) and X-ray diffraction (XRD). Their individual deposition rate and electromagnetic interference (EMI) shielding effectiveness (SE) were also investigated to compare the properties of electroless nickel films. SEM images illustrated that the nickel film on MA modified CF substrate was smooth and uniform, and the density of nickel nuclei was much higher. Compared with that of CA modified CF, the coverage of nickel nuclei on OA and MA modified CF substrate was very limited and the nickel particles size was too big. XRD analysis showed that the nickel films deposited on the different modified CF substrates had a structure with Ni (1 1 1) preferred orientation. All the nickel coatings via different acid modification were firmly adhered to the CF substrates, as demonstrated by an ultrasonic washing test. The result of tensile test indicated that the electroless nickel plating on CF has ability to strengthen the CF substrate while causes limited effect on tensile elongation. Moreover, the nickel film deposited on MA modified CF substrate showed more predominant in EMI SE than that deposited on CA or OA modified CF.

  13. Biodynamic performance of hyaluronic acid versus synovial fluid of the knee in osteoarthritis.

    PubMed

    Corvelli, Michael; Che, Bernadette; Saeui, Christopher; Singh, Anirudha; Elisseeff, Jennifer

    2015-08-01

    Hyaluronic acid (HA), a natural biomaterial present in healthy joints but depleted in osteoarthritis (OA), has been employed clinically to provide symptomatic relief of joint pain. Joint movement combined with a reduced joint lubrication in osteoarthritic knees can result in increased wear and tear, chondrocyte apoptosis, and inflammation, leading to cascading cartilage deterioration. Therefore, development of an appropriate cartilage model that can be evaluated for its friction properties with potential lubricants in different conditions is necessary, which can closely resemble a mechanically induced OA cartilage. Additionally, a comparison of different models with and without endogenous lubricating surface zone proteins, such as PRG4 promotes a well-rounded understanding of cartilage lubrication. In this study, we present our findings on the lubricating effects of HA on different articular cartilage model surfaces in comparison to synovial fluid, a physiological lubricating biomaterial. The mechanical testings data demonstrated that HA reduced average static and kinetic friction coefficient values of the cartilage samples by 75% and 70%, respectively. Furthermore, HA mimicked the friction characteristics of freshly harvested natural synovial fluid throughout all tested and modeled OA conditions with no statistically significant difference. These characteristics led us to exclusively identify HA as an effective boundary layer lubricant in the technology that we develop to treat OA (Singh et al., 2014).

  14. The bryophyte Fontinalis antipyretica Hedw. bioaccumulates oxytetracycline, flumequine and oxolinic acid in the freshwater environment.

    PubMed

    Delépée, Raphaël; Pouliquen, Hervé; Le Bris, Hervé

    2004-04-25

    In recent years, the fate of pharmacological substances in the aquatic environment have been more and more studied. Oxolinic acid (OA), flumequine (FLU) and oxytetracycline (OTC) are commonly used antibacterial agents. A large amount of these drugs is released into water directly by dissolved fraction and indirectly in urine and feces. Monitoring these compounds in the freshwater environment is difficult because of the lack of suitable indicators. The aim of this work was to evaluate the OA, FLU and OTC bioaccumulation abilities of Fontinalis antipyretica Hedw., known for heavy metal bioaccumulation. The experiment described was decomposed for two times: a 10-days accumulation period during which bryophytes were in contact with antibiotics and a 15-days post-exposure period during which bryophytes were in water with no antibiotic. This experiment showed that this bryophyte strongly accumulates OA, FLU and OTC in freshwater. Bioaccumulation factors (ratio of concentrations in bryophyte and water) ranged between 75 and 450. Moreover, OA, FLU and OTC persisted in the bryophyte for a long time with clearance between 0.19 and 3.04 ng/g/day. Mean residence times ranged between 18 and 59 days. Accumulation and decontamination mechanism models were proposed.

  15. Non-enzymatic oxalic acid sensor using platinum nanoparticles modified on graphene nanosheets.

    PubMed

    Chen, Xiaomei; Cai, Zhixiong; Huang, Zhiyong; Oyama, Munetaka; Jiang, Yaqi; Chen, Xi

    2013-07-07

    An enzyme-free oxalic acid (OA) electrochemical sensor was assembled using a platinum nanoparticle-loaded graphene nanosheets (PtNPGNs)-modified electrode. The PtNPGNs, with a high yield of PtNPs dispersed on the graphene nanosheets, were successfully achieved by a green, rapid, one-step and template-free method. The resulting PtNPGNs were characterized by transmission electron microscopy (TEM), high-resolution TEM, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and an X-ray diffraction technique. Electrochemical oxidation of OA on the PtNPGNs-modified electrode was investigated by cyclic voltammetry and differential pulse voltammetry methods. Based on the results, the modified electrode exhibited high electrochemical activity with well-defined peaks of OA oxidation and a notably decreased overpotential compared to the bare or even the GNs-modified electrode. Under optimized conditions, a good linear response was observed for the concentration of OA and its current response was in the range of 0.1-15 mM and 15-50 mM with a detection limit (S/N = 3) of 10 μM. Furthermore, the electrochemical sensor presented good characteristics in terms of stability and reproducibility, promising the applicability of the sensor in practical analysis.

  16. Effects of oleic acid-induced lung injury on oxygen transport and aerobic capacity.

    PubMed

    Crocker, George H; Jones, James H

    2014-06-01

    We tested the hypothesis that oleic-acid (OA) infusion impairs gas exchange, decreases total cardiopulmonary O2 delivery and lowers maximal aerobic capacity ( [Formula: see text] ). We infused 0.05ml OAkg(-1) (∼3ml) and ∼563ml saline into the right atria of four goats [59.1±14.0 (SD) kg] prior to running them on a treadmill at [Formula: see text] 2-h and 1-d following OA-induced acute lung injury, and with no lung injury. Acute lung injury decreased [Formula: see text] , O2 delivery, arterial O2 concentration and arterial O2 partial pressure compared to no lung injury. The [Formula: see text] positively correlated with O2 delivery and inversely correlated with alveolar-arterial O2 partial pressure difference, suggesting that impaired pulmonary gas exchange decreased O2 delivery and uptake. Results indicate OA infusion may be a useful model for acutely impairing pulmonary gas exchange for exercise studies. Seven OA infusions induced smaller chronic gas exchange and arterial O2 partial pressure changes than acute infusion.

  17. Application of silver nanofluid containing oleic acid surfactant in a thermosyphon economizer

    PubMed Central

    2011-01-01

    This article reports a recent study on the application of a two-phase closed thermosyphon (TPCT) in a thermosyphon for economizer (TPEC). The TPEC had three sections of equal size; the evaporator, the adiabatic section, and the condenser, of 250 mm × 250 mm × 250 mm (W × L × H). The TPCT was a steel tube of 12.7-mm ID. The filling ratios chosen to study were 30, 50, and 80% with respect to the evaporator length. The volumetric flow rates for the coolant (in the condenser) were 1, 2.5, and 5 l/min. Five working fluids investigated were: water, water-based silver nanofluid with silver concentration 0.5 w/v%, and the nanofluid (NF) mixed with 0.5, 1, and 1.5 w/v% of oleic acid (OA). The operating temperatures were 60, 70, and 80°C. Experimental data showed that the TPEC gave the highest heat flux of about 25 kW/m2 and the highest effectiveness of about 0.3 at a filling ratio of 50%, with the nanofluid containing 1 w/v% of OA. It was further found that the effectiveness of nanofluid and the OA containing nanofluids were superior in effectiveness over water in all experimental conditions came under this study. Moreover, the presence of OA had clearly contributed to raise the effectiveness of the nanofluid. PMID:21711856

  18. Amino Acid Residues Critical for the Specificity for Betaine Aldehyde of the Plant ALDH10 Isoenzyme Involved in the Synthesis of Glycine Betaine1[W][OA

    PubMed Central

    Díaz-Sánchez, Ángel G.; González-Segura, Lilian; Mújica-Jiménez, Carlos; Rudiño-Piñera, Enrique; Montiel, Carmina; Martínez-Castilla, León P.; Muñoz-Clares, Rosario A.

    2012-01-01

    Plant Aldehyde Dehydrogenase10 (ALDH10) enzymes catalyze the oxidation of ω-primary or ω-quaternary aminoaldehydes, but, intriguingly, only some of them, such as the spinach (Spinacia oleracea) betaine aldehyde dehydrogenase (SoBADH), efficiently oxidize betaine aldehyde (BAL) forming the osmoprotectant glycine betaine (GB), which confers tolerance to osmotic stress. The crystal structure of SoBADH reported here shows tyrosine (Tyr)-160, tryptophan (Trp)-167, Trp-285, and Trp-456 in an arrangement suitable for cation-π interactions with the trimethylammonium group of BAL. Mutation of these residues to alanine (Ala) resulted in significant Km(BAL) increases and Vmax/Km(BAL) decreases, particularly in the Y160A mutant. Tyr-160 and Trp-456, strictly conserved in plant ALDH10s, form a pocket where the bulky trimethylammonium group binds. This space is reduced in ALDH10s with low BADH activity, because an isoleucine (Ile) pushes the Trp against the Tyr. Those with high BADH activity instead have Ala (Ala-441 in SoBADH) or cysteine, which allow enough room for binding of BAL. Accordingly, the mutation A441I decreased the Vmax/Km(BAL) of SoBADH approximately 200 times, while the mutation A441C had no effect. The kinetics with other ω-aminoaldehydes were not affected in the A441I or A441C mutant, demonstrating that the existence of an Ile in the second sphere of interaction of the aldehyde is critical for discriminating against BAL in some plant ALDH10s. A survey of the known sequences indicates that plants have two ALDH10 isoenzymes: those known to be GB accumulators have a high-BAL-affinity isoenzyme with Ala or cysteine in this critical position, while non GB accumulators have low-BAL-affinity isoenzymes containing Ile. Therefore, BADH activity appears to restrict GB synthesis in non-GB-accumulator plants. PMID:22345508

  19. First U.S. report of shellfish harvesting closures due to confirmed okadaic acid in Texas Gulf coast oysters.

    PubMed

    Deeds, Jonathan R; Wiles, Kirk; Heideman, Gary B; White, Kevin D; Abraham, Ann

    2010-06-01

    Between March 7 and April 12, 2008, several bay systems on the east (Gulf of Mexico) coast of Texas, USA were closed to the harvesting of oysters (Crassostrea virginica) due to the presence of the DSP (Diarrheic Shellfish Poisoning) toxin okadaic acid in excess of the 20 microg/100 g tissue FDA regulatory guidance level. This was the first shellfish harvesting closure due to the confirmed presence of DSP toxins in US history. Light microscopic cell counts were performed on water samples collected from numerous sampling sites along the Texas Gulf coast where shellfish harvesting occurs. Ultra performance liquid chromatography, electrospray ionization, selected reaction monitoring, mass spectrometry (UPLC/ESI/SRM/MS) was used to detect DSP toxins in oysters. The closures were associated with an extensive bloom of the dinoflagellate Dinophysis cf. ovum. Only okadaic acid (OA) and OA acyl esters were found in shellfish tissues (max. OA eq. levels 47 microg/100 g tissue). OA was also confirmed in a bloom water sample. No illnesses were reported associated with this event. DSP toxins now add to a growing list of phycotoxins, which include those responsible for PSP (paralytic shellfish poisoning), NSP (neurotoxic shellfish poisoning), and ASP (amnesic shellfish poisoning) which must now be monitored for in US coastal waters where shellfish are harvested.

  20. c-Jun N-terminal Kinase (JNK) induces phosphorylation of amyloid precursor protein (APP) at Thr668, in okadaic acid-induced neurodegeneration

    PubMed Central

    Ahn, Ji-Hwan; So, Sang-Pil; Kim, Na-Young; Kim, Hyun-Ju; Yoon, Seung-Yong; Kim, Dong-Hou

    2016-01-01

    Several lines of evidence have revealed that phosphorylation of amyloid precursor protein (APP) at Thr668 is involved in the pathogenesis of Alzheimer’s disease (AD). Okadaic acid (OA), a protein phosphatase-2A inhibitor, has been used in AD research models to increase tau phosphorylation and induce neuronal death. We previously showed that OA increased levels of APP and induced accumulation of APP in axonal swellings. In this study, we found that in OA-treated neurons, phosphorylation of APP at Thr668 increased and accumulated in axonal swellings by c-jun N-terminal kinase (JNK), and not by Cdk5 or ERK/MAPK. These results suggest that JNK may be one of therapeutic targets for the treatment of AD. [BMB Reports 2016; 49(7): 376-381] PMID:26839154

  1. Diarrhetic Shellfish Toxins and Other Lipophilic Toxins of Human Health Concern in Washington State

    PubMed Central

    Trainer, Vera L.; Moore, Leslie; Bill, Brian D.; Adams, Nicolaus G.; Harrington, Neil; Borchert, Jerry; da Silva, Denis A. M.; Eberhart, Bich-Thuy L.

    2013-01-01

    The illness of three people in 2011 after their ingestion of mussels collected from Sequim Bay State Park, Washington State, USA, demonstrated the need to monitor diarrhetic shellfish toxins (DSTs) in Washington State for the protection of human health. Following these cases of diarrhetic shellfish poisoning, monitoring for DSTs in Washington State became formalized in 2012, guided by routine monitoring of Dinophysis species by the SoundToxins program in Puget Sound and the Olympic Region Harmful Algal Bloom (ORHAB) partnership on the outer Washington State coast. Here we show that the DSTs at concentrations above the guidance level of 16 μg okadaic acid (OA) + dinophysistoxins (DTXs)/100 g shellfish tissue were widespread in sentinel mussels throughout Puget Sound in summer 2012 and included harvest closures of California mussel, varnish clam, manila clam and Pacific oyster. Concentrations of toxins in Pacific oyster and manila clam were often at least half those measured in blue mussels at the same site. The primary toxin isomer in shellfish and plankton samples was dinophysistoxin-1 (DTX-1) with D. acuminata as the primary Dinophysis species. Other lipophilic toxins in shellfish were pectenotoxin-2 (PTX-2) and yessotoxin (YTX) with azaspiracid-2 (AZA-2) also measured in phytoplankton samples. Okadaic acid, azaspiracid-1 (AZA-1) and azaspiracid-3 (AZA-3) were all below the levels of detection by liquid chromatography tandem mass spectrometry (LC-MS/MS). A shellfish closure at Ruby Beach, Washington, was the first ever noted on the Washington State Pacific coast due to DSTs. The greater than average Fraser River flow during the summers of 2011 and 2012 may have provided an environment conducive to dinoflagellates and played a role in the prevalence of toxigenic Dinophysis in Puget Sound. PMID:23760013

  2. Diarrhetic shellfish toxins and other lipophilic toxins of human health concern in Washington State.

    PubMed

    Trainer, Vera L; Moore, Leslie; Bill, Brian D; Adams, Nicolaus G; Harrington, Neil; Borchert, Jerry; da Silva, Denis A M; Eberhart, Bich-Thuy L

    2013-05-28

    The illness of three people in 2011 after their ingestion of mussels collected from Sequim Bay State Park, Washington State, USA, demonstrated the need to monitor diarrhetic shellfish toxins (DSTs) in Washington State for the protection of human health. Following these cases of diarrhetic shellfish poisoning, monitoring for DSTs in Washington State became formalized in 2012, guided by routine monitoring of Dinophysis species by the SoundToxins program in Puget Sound and the Olympic Region Harmful Algal Bloom (ORHAB) partnership on the outer Washington State coast. Here we show that the DSTs at concentrations above the guidance level of 16 μg okadaic acid (OA) + dinophysistoxins (DTXs)/100 g shellfish tissue were widespread in sentinel mussels throughout Puget Sound in summer 2012 and included harvest closures of California mussel, varnish clam, manila clam and Pacific oyster. Concentrations of toxins in Pacific oyster and manila clam were often at least half those measured in blue mussels at the same site. The primary toxin isomer in shellfish and plankton samples was dinophysistoxin-1 (DTX-1) with D. acuminata as the primary Dinophysis species. Other lipophilic toxins in shellfish were pectenotoxin-2 (PTX-2) and yessotoxin (YTX) with azaspiracid-2 (AZA-2) also measured in phytoplankton samples. Okadaic acid, azaspiracid-1 (AZA-1) and azaspiracid-3 (AZA-3) were all below the levels of detection by liquid chromatography tandem mass spectrometry (LC-MS/MS). A shellfish closure at Ruby Beach, Washington, was the first ever noted on the Washington State Pacific coast due to DSTs. The greater than average Fraser River flow during the summers of 2011 and 2012 may have provided an environment conducive to dinoflagellates and played a role in the prevalence of toxigenic Dinophysis in Puget Sound.

  3. Efficacy study of two novel hyaluronic acid-based formulations for viscosupplementation therapy in an early osteoarthrosic rabbit model.