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Sample records for acid-derived lipid mediators

  1. Metabonomics Reveals Drastic Changes in Anti-Inflammatory/Pro-Resolving Polyunsaturated Fatty Acids-Derived Lipid Mediators in Leprosy Disease

    PubMed Central

    Amaral, Julio J.; Antunes, Luis Caetano M.; de Macedo, Cristiana S.; Mattos, Katherine A.; Han, Jun; Pan, Jingxi; Candéa, André L. P.; Henriques, Maria das Graças M. O.; Ribeiro-Alves, Marcelo; Borchers, Christoph H.; Sarno, Euzenir N.; Bozza, Patrícia T.; Finlay, B. Brett; Pessolani, Maria Cristina V.

    2013-01-01

    Despite considerable efforts over the last decades, our understanding of leprosy pathogenesis remains limited. The complex interplay between pathogens and hosts has profound effects on host metabolism. To explore the metabolic perturbations associated with leprosy, we analyzed the serum metabolome of leprosy patients. Samples collected from lepromatous and tuberculoid patients before and immediately after the conclusion of multidrug therapy (MDT) were subjected to high-throughput metabolic profiling. Our results show marked metabolic alterations during leprosy that subside at the conclusion of MDT. Pathways showing the highest modulation were related to polyunsaturated fatty acid (PUFA) metabolism, with emphasis on anti-inflammatory, pro-resolving omega-3 fatty acids. These results were confirmed by eicosanoid measurements through enzyme-linked immunoassays. Corroborating the repertoire of metabolites altered in sera, metabonomic analysis of skin specimens revealed alterations in the levels of lipids derived from lipase activity, including PUFAs, suggesting a high lipid turnover in highly-infected lesions. Our data suggest that omega-6 and omega-3, PUFA-derived, pro-resolving lipid mediators contribute to reduced tissue damage irrespectively of pathogen burden during leprosy disease. Our results demonstrate the utility of a comprehensive metabonomic approach for identifying potential contributors to disease pathology that may facilitate the development of more targeted treatments for leprosy and other inflammatory diseases. PMID:23967366

  2. Arachidonic acid-derived signaling lipids and functions in impaired healing

    PubMed Central

    Dhall, Sandeep; Wijesinghe, Dayanjan Shanaka; Karim, Zubair A.; Castro, Anthony; Vemana, Hari Priya; Khasawneh, Fadi T.; Chalfant, Charles E.; Martins-Green, Manuela

    2016-01-01

    Very little is known about lipid function during wound healing, and much less during impaired healing. Such understanding will help identify what roles lipid signaling plays in the development of impaired/chronic wounds. We took a lipidomics approach to study the alterations in lipid profile in the LIGHT−/− mouse model of impaired healing which has characteristics that resemble those of impaired/chronic wounds in humans, including high levels of oxidative stress, excess inflammation, increased extracellular matrix degradation and blood vessels with fibrin cuffs. The latter suggests excess coagulation and potentially increased platelet aggregation. We show here that in these impaired wounds there is an imbalance in the arachidonic acid (AA) derived eicosonoids that mediate or modulate inflammatory reactions and platelet aggregation. In the LIGHT−/− impaired wounds there is a significant increase in enzymatically derived breakdown products of AA. We found that early after injury there was a significant increase in the eicosanoids 11-, 12-, and 15-hydroxyeicosa-tetranoic acid, and the proinflammatory leukotrienes (LTD4 and LTE) and prostaglandins (PGE2 and PGF2α). Some of these eicosanoids also promote platelet aggregation. This led us to examine the levels of other eicosanoids known to be involved in the latter process. We found that thromboxane (TXA2/B2), and prostacyclins 6kPGF1α are elevated shortly after wounding and in some cases during healing. To determine whether they have an impact in platelet aggregation and hemostasis, we tested LIGHT−/− mouse wounds for these two parameters and found that, indeed, platelet aggregation and hemostasis are enhanced in these mice when compared with the control C57BL/6 mice. Understanding lipid signaling in impaired wounds can potentially lead to development of new therapeutics or in using existing nonsteroidal anti-inflammatory agents to help correct the course of healing. PMID:26135854

  3. Lipid-Mediated Endocytosis

    PubMed Central

    Ewers, Helge; Helenius, Ari

    2011-01-01

    Receptor-mediated endocytosis is used by a number of viruses and toxins to gain entry into cells. Some have evolved to use specific lipids in the plasma membrane as their receptors. They include bacterial toxins such as Shiga and Cholera toxin and viruses such as mouse polyoma virus and simian virus 40. Through multivalent binding to glycosphingolipids, they induce lipid clustering and changes in membrane properties. Internalization occurs by unusual endocytic mechanisms involving lipid rafts, induction of membrane curvature, trans-bilayer coupling, and activation of signaling pathways. Once delivered to early endosomes, they follow diverse intracellular routes to the lumen of the ER, from which they penetrate into the cytosol. The role of the lipid receptors is central in these well-studied processes. PMID:21576253

  4. Deoxycholic acid derivatives as inhibitors of P-glycoprotein-mediated multidrug efflux.

    PubMed

    Rocheblave, Luc; de Ravel, Marc Rolland; Monniot, Elodie; Tavenard, Jeremy; Cuilleron, Claude-Yves; Grenot, Catherine; Radix, Sylvie; Matera, Eva-Laure; Dumontet, Charles; Walchshofer, Nadia

    2016-12-01

    Deoxycholic acid derivatives were designed as P-glycoprotein (Pgp, ABCB1) inhibitors. Thus the synthesis and the biological activity of methyl deoxycholate derivatives 5-10 and their ether analogs 15-20 have been reported. The potency of these compounds to modulate Pgp-mediated MDR was evaluated through daunorubicin accumulation and potentiation of doxorubicin cytotoxicity in K562/R7 multidrug resistant cells overexpressing Pgp. In parallel, their intrinsic toxicity was appreciated on K562 sensitive cells. Methyl 12α-[(2R or 2S) tetrahydro-2H-pyran-2-yloxy]-3-oxo-5β-cholan-24-oate 9b has shown a good efficiency as a Pgp inhibitor and a low intrinsic toxicity. Therefore, this derivative constitutes a new lead compound which can be used as a starting point to improve the design of non-toxic Pgp modulators.

  5. In vitro inhibition of OATP-mediated uptake of phalloidin using bile acid derivatives

    SciTech Connect

    Herraez, Elisa; Macias, Rocio I.R.; Vazquez-Tato, Jose; Vicens, Marta; Monte, Maria J.; Marin, Jose J.G.

    2009-08-15

    Hepatocyte uptake of phalloidin is carried out mainly by OATP1B1. We have used this compound as a prototypic substrate and assayed the ability to inhibit OATP-mediated phalloidin transport of four bile acid derivatives (BALU-1, BALU-2, BALU-3 and BALU-4) that showed positive results in preliminary screening. Using Xenopus laevis oocytes for heterologous expression of transporters, BALUs were found to inhibit taurocholic acid (TCA) transport by OATP1B1 (but not OATP1B3) as well as by rat Oatp1a1, Oatp1a4 and Oatp1b2. The study of their ability to inhibit sodium-dependent bile acid transporters revealed that the four BALUs induced an inhibition of rat Asbt-mediated TCA transport, which was similar to TCA-induced self-inhibition. Regarding human NTCP and rat Ntcp, BALU-1 differs from the other three BALUS in its lack of effect on TCA transport by these proteins. Using HPLC-MS/MS and CHO cells stably expressing OATP1B1 the ability of BALU-1 to inhibit the uptake of phalloidin itself by this transporter was confirmed. Kinetic analysis using X. laevis oocytes revealed that BALU-1-induced inhibition of OATP1B1 was mainly due to a competitive mechanism (Ki = 8 {mu}M). In conclusion, BALU-1 may be useful as a pharmacological tool to inhibit the uptake of compounds mainly taken up by OATP1B1 presumably without impairing bile acid uptake by the major carrier accounting for this process, i.e., NTCP.

  6. Bioconversion of volatile fatty acids derived from waste activated sludge into lipids by Cryptococcus curvatus.

    PubMed

    Liu, Jia; Liu, Jia-Nan; Yuan, Ming; Shen, Zi-Heng; Peng, Kai-Ming; Lu, Li-Jun; Huang, Xiang-Feng

    2016-07-01

    Pure volatile fatty acid (VFA) solution derived from waste activated sludge (WAS) was used to produce microbial lipids as culture medium in this study, which aimed to realize the resource recovery of WAS and provide low-cost feedstock for biodiesel production simultaneously. Cryptococcus curvatus was selected among three oleaginous yeast to produce lipids with VFAs derived from WAS. In batch cultivation, lipid contents increased from 10.2% to 16.8% when carbon to nitrogen ratio increased from about 3.5 to 165 after removal of ammonia nitrogen by struvite precipitation. The lipid content further increased to 39.6% and the biomass increased from 1.56g/L to 4.53g/L after cultivation for five cycles using sequencing batch culture (SBC) strategy. The lipids produced from WAS-derived VFA solution contained nearly 50% of monounsaturated fatty acids, including palmitic acid, heptadecanoic acid, ginkgolic acid, stearic acid, oleic acid, and linoleic acid, which showed the adequacy of biodiesel production.

  7. Lipid Mediators in Acne

    PubMed Central

    Ottaviani, Monica; Camera, Emanuela; Picardo, Mauro

    2010-01-01

    Multiple factors are involved in acne pathogenesis, and sebum secretion is one of the main ones. The role sebum plays in acne development has not been completely elucidated yet; however, increasing amounts of data seem to confirm the presence of alterations in sebum from acne patients. Altered ratio between saturated and unsaturated fatty acids has been indicated as an important feature to be considered in addition to the altered amount of specific fatty acids such as linoleic acid. Furthermore, particular attention has been focused on squalene peroxide that seems to be able to induce an inflammatory response beyond cytotoxicity and comedones formation. Moreover, recent data suggest that lipid mediators are able to interfere with sebocytes differentiation and sebogenesis through the activation of pathways related to peroxisome proliferators-activated receptors. Understanding the factors and mechanisms that regulate sebum production is needed in order to identify novel therapeutic strategies for acne treatment. PMID:20871834

  8. Lipid mediators in the neural cell nucleus: their metabolism, signaling, and association with neurological disorders.

    PubMed

    Farooqui, Akhlaq A

    2009-08-01

    Lipid mediators are important endogenous regulators of neural cell proliferation, differentiation, oxidative stress, inflammation, and apoptosis. They originate from enzymic degradation of glycerophospholipids, sphingolipids, and cholesterol by phospholipases, sphingomyelinases, and cytochrome P450 hydroxylases, respectively. Arachidonic acid-derived lipid mediators are called eicosanoids. Eicosanoids have emerged as key regulators of cell proliferation, differentiation, oxidative stress, and neuroinflammation. Another arachidonic acid-derived lipid mediator is lipoxin. Eicosanoids have proinflammatory effects, whereas lipoxins produce antiinflammatory effects. The crossponding lipid mediators of docosahexaenoic acid metabolism are named docosanoids. They include resolvins, protectins, and neuroprotectins. Docosanoids produce antioxidant, anti-inflammatory, and antiapoptotic effects in the brain tissue. Other glycerophospholipid-derived lipid mediators are platelet-activating factor, lysophosphatidic acid, and endocannabinoids. Degradation of sphingolipids also results in the generation of sphingolipid-derived lipid mediators. Sphingolipid-derived lipid mediators are ceramide, ceramide 1-phosphate, sphingosine, and sphingosine 1-phosphate. They mediate cellular differentiation, cell growth, and apoptosis. Similarly, cholesterol-derived lipid mediators hydroxycholesterol and oxycholesterol produce apoptosis. Most of these mediators originate from the plasma membrane. The nucleus has its own set of enzymes and lipid mediators that originate from the nuclear envelope and matrix. The purpose of this commentary is to describe basic and clinical information on lipid mediators in the nucleus.

  9. Lipid mediators in diabetic nephropathy

    PubMed Central

    2014-01-01

    The implications of lipid lowering drugs in the treatment of diabetic nephropathy have been considered. At the same time, the clinical efficacy of lipid lowering drugs has resulted in improvement in the cardiovascular functions of chronic kidney disease (CKD) patients with or without diabetes, but no remarkable improvement has been observed in the kidney outcome. Earlier lipid mediators have been shown to cause accumulative effects in diabetic nephropathy (DN). Here, we attempt to analyze the involvement of lipid mediators in DN. The hyperglycemia-induced overproduction of diacyglycerol (DAG) is one of the causes for the activation of protein kinase C (PKCs), which is responsible for the activation of pathways, including the production of VEGF, TGFβ1, PAI-1, NADPH oxidases, and NFҟB signaling, accelerating the development of DN. Additionally, current studies on the role of ceramide are one of the major fields of study in DN. Researchers have reported excessive ceramide formation in the pathobiological conditions of DN. There is less report on the effect of lipid lowering drugs on the reduction of PKC activation and ceramide synthesis. Regulating PKC activation and ceramide biosynthesis could be a protective measure in the therapeutic potential of DN. Lipid lowering drugs also upregulate anti-fibrotic microRNAs, which could hint at the effects of lipid lowering drugs in DN. PMID:25206927

  10. [Effect of 3-oxypyridine and succinic acid derivatives on endometrial leucocyte infiltration and lipid peroxidation in recrudescence of inflammatory diseases of the uterus and its appendages].

    PubMed

    Volchegorskiĭ, I A; Pravdin, E V; Uzlova, T V

    2013-01-01

    The effect of domestic 3-oxypyridine and succinic acid derivatives (emoxipin, reamberin and mexidol) included in the complex treatment of recrudescence of inflammatory diseases of the uterus and its appendages, as manifested in endometrial leucocyte infiltration (ELI) compared to lipid peroxidation products concentration in blood serum, was assessed in a short-term, prospective placebo-controlled single-blind randomized trial. It has been found that two-week infusions of emoxipin (single dose, 150 mg), reamberin (single dose, 400 ml), and mexidol (single dose, 300 mg) favor a decrease in ELI and influence ambiguously on lipid peroxidation - antioxidant (LPA) system condition in blood serum of patients. It has been found that 3-oxypyridine derivative (emoxipin) decreases the intensity of ELI, but does not affect LPA system condition. Succinic acid derivative (reamberin) is inferior to emoxipin in the degree of decreasing ELI, but reduces the concentration of the antioxidant protein ceruloplasmin. Mexidol, being 3-oxipyridine and succinic acid derivative simultaneously, exceeds reamberin in decreasing ELI, increases concentration of blood antioxidant components (alpha-tocopherol and ceruloplasmin), and decreases the level of primary isopropanol-soluble products of lipid peroxidation.

  11. Magnesium-mediated intramolecular reductive coupling: a stereoselective synthesis of C(2)-symmetric 3,4-bis-silyl-substituted adipic acid derivatives.

    PubMed

    Kundu, Pintu K; Ghosh, Sunil K

    2009-11-21

    Chiral C(2)-symmetric 3,4-bis-silyl-substituted adipic acid derivatives have been synthesised by a Mg/trimethylsilyl chloride-mediated intramolecular reductive coupling of symmetrical disiloxanes of beta-silylacrylic acid N-oxazolidinone derivatives. Efficient and short syntheses of enantiomerically pure enantiomers of 2,6-dioxabicyclo[3.3.0]octane-3,7-dione have been achieved from the bis-silylated adipic acid derivatives using Fleming-Tamao oxidation as the key step.

  12. Volatile fatty acids derived from waste organics provide an economical carbon source for microbial lipids/biodiesel production.

    PubMed

    Park, Gwon Woo; Fei, Qiang; Jung, Kwonsu; Chang, Ho Nam; Kim, Yeu-Chun; Kim, Nag-jong; Choi, Jin-dal-rae; Kim, Sangyong; Cho, Jaehoon

    2014-12-01

    Volatile fatty acids (VFAs) derived from organic waste, were used as a low cost carbon source for high bioreactor productivity and titer. A multi-stage continuous high cell density culture (MSC-HCDC) process was employed for economic assessment of microbial lipids for biodiesel production. In a simulation study we used a lipid yield of 0.3 g/g-VFAs, cell mass yield of 0.5 g/g-glucose or wood hydrolyzates, and employed process variables including lipid contents from 10-90% of cell mass, bioreactor productivity of 0.5-48 g/L/h, and plant capacity of 20000-1000000 metric ton (MT)/year. A production cost of USD 1.048/kg-lipid was predicted with raw material costs of USD 0.2/kg for wood hydrolyzates and USD 0.15/kg for VFAs; 9 g/L/h bioreactor productivity; 100, 000 MT/year production capacity; and 75% lipids content. The variables having the highest impact on microbial lipid production costs were the cost of VFAs and lipid yield, followed by lipid content, fermenter cost, and lipid productivity. The cost of raw materials accounted for 66.25% of total operating costs. This study shows that biodiesel from microbial lipids has the potential to become competitive with diesels from other sources.

  13. Lipid mediators of insulin resistance.

    PubMed

    Holland, William L; Knotts, Trina A; Chavez, Jose A; Wang, Li-Ping; Hoehn, Kyle L; Summers, Scott A

    2007-06-01

    Lipid abnormalities such as obesity, increased circulating free fatty acid levels, and excess intramyocellular lipid accumulation are frequently associated with insulin resistance. These observations have prompted investigators to speculate that the accumulation of lipids in tissues not suited for fat storage (e.g., skeletal muscle and liver) is an underlying component of insulin resistance and the metabolic syndrome. We review the metabolic fates of lipids in insulin-responsive tissues and discuss the roles of specific lipid metabolites (e.g., ceramides, GM3 ganglioside, and diacylglycerol) as antagonists of insulin signaling and action.

  14. [EFfect of quinazolone-alkyl-carboxylic acid derivatives on the transmembrane Ca2+ ion flux mediated by AMPA receptors].

    PubMed

    Szárics, Eva; LaszTóczi, Bálint; Nyikos, Lajos; Barabás, Péter; Kovács, Ilona; Skuban, Nina; Nagy, Péter I; Kökösi, József; Takácsné, Novák Krisztina; Kardos, Julianna

    2002-01-01

    The excitatory neurotransmitter, Glu, plays a crucial role in many sensory and motor functions as well as in brain development, learning and memory and it is also involved in the pathogenesis of a number of neurological disorders, including epilepsy, Alzheimer's and Parkinson's diseases. Therefore, the study of Glu receptors (GluRs) is of therapeutical importance. We showed here by fluorescence monitoring of transmembrane Ca2+ ion fluxes in response to (S)-alpha-amino-3-hidroxi-5-metil-4-izoxazol propionic acid ((S)-AMPA) on the time scale of 0.00004-10 s that Ca2+ ion influx proceeds through faster and slower desensitizing receptors. Pharmacological isolation of the slower and faster desensitizing AMPA receptor was possible by fluorescence monitoring of Ca2+ ion translocation in response to (S)-AMPA in the presence and absence of various 2-methyl-4-oxo-3H-quinazoline-3-alkyl-carboxilic acid derivatives (Qxs): the acetic acid Q1 inhibits the slower desensitizing receptor response specifically, while the acetyl-piperidine Q5 is a more potent inhibitor of the faster desensitizing receptor response. In addition, spontaneous interictal activity, as induced by high [K+] conditions in hippocampal slices, was reduced significantly by Q5, suggesting a possible anticonvulsant property of Q5. Substitutions of Qxs into the GluR2 S1S2 binding core were consistent with their effect by causing variable degree of S1S2 bridging interaction as one of the main determinants of AMPA receptor agonist activity. The exploitation of differences between similar receptors will be important in the development and use of drugs with high pharmacological specificity.

  15. Amino acid derivative-mediated detoxification and functionalization of dual cure dental restorative material for dental pulp cell mineralization.

    PubMed

    Minamikawa, Hajime; Yamada, Masahiro; Iwasa, Fuminori; Ueno, Takeshi; Deyama, Yoshiaki; Suzuki, Kuniaki; Yawaka, Yasutaka; Ogawa, Takahiro

    2010-10-01

    Current dental restorative materials are only used to fill the defect of hard tissues, such as dentin and enamel, because of their cytotoxicity. Therefore, exposed dental pulp tissues in deep cavities must be first covered by a pulp capping material like calcium hydroxide to form a layer of mineralized tissue. However, this tissue mineralization is based on pathological reaction and triggers long-lasting inflammation, often causing clinical problems. This study tested the ability of N-acetyl cysteine (NAC), amino acid derivative, to reduce cytotoxicity and induce mineralized tissue conductivity in resin-modified glass ionomer (RMGI), a widely used dental restorative material having dual cure mechanism. Rat dental pulp cells were cultured on untreated or NAC-supplemented RMGI. NAC supplementation substantially increased the percentage of viable cells from 46.7 to 73.3% after 24-h incubation. Cell attachment, spreading, proliferative activity, and odontoblast-related gene and protein expressions increased significantly on NAC-supplemented RMGI. The mineralization capability of cells, which was nearly suppressed on untreated RMGI, was induced on NAC-supplemented RMGI. These improved behaviors and functions of dental pulp cells on NAC-supplemented RMGI were associated with a considerable reduction in the production of intracellular reactive oxygen species and with the increased level of intracellular glutathione reserves. These results demonstrated that NAC could detoxify and functionalize RMGIs via two different mechanisms involving in situ material detoxification and antioxidant cell protection. We believe that this study provides a new approach for developing dental restorative materials that enables mineralized tissue regeneration.

  16. Carbon Nanotubes Mediate Fusion of Lipid Vesicles.

    PubMed

    Bhaskara, Ramachandra M; Linker, Stephanie M; Vögele, Martin; Köfinger, Jürgen; Hummer, Gerhard

    2017-02-28

    The fusion of lipid membranes is opposed by high energetic barriers. In living organisms, complex protein machineries carry out this biologically essential process. Here we show that membrane-spanning carbon nanotubes (CNTs) can trigger spontaneous fusion of small lipid vesicles. In coarse-grained molecular dynamics simulations, we find that a CNT bridging between two vesicles locally perturbs their lipid structure. Their outer leaflets merge as the CNT pulls lipids out of the membranes, creating an hourglass-shaped fusion intermediate with still intact inner leaflets. As the CNT moves away from the symmetry axis connecting the vesicle centers, the inner leaflets merge, forming a pore that completes fusion. The distinct mechanism of CNT-mediated membrane fusion may be transferable, providing guidance in the development of fusion agents, e.g., for the targeted delivery of drugs or nucleic acids.

  17. Peroxynitrite-mediated formation of free radicals in human plasma: EPR detection of ascorbyl, albumin-thiyl and uric acid-derived free radicals.

    PubMed Central

    Vásquez-Vivar, J; Santos, A M; Junqueira, V B; Augusto, O

    1996-01-01

    Formation of peroxynitrite by the fast reaction between nitric oxide and superoxide anion may represent a critical control point in cells producing both species, leading to either down-regulation of the physiological effects of superoxide anion and nitric oxide by forming an inert product, nitrate, or to potentiation of their toxic effects by oxidation of nearby molecules by peroxynitrite. (The term peroxynitrite is used to refer to the sum of all possible forms of peroxynitrite anion and peroxynitrous acid unless otherwise specified.) In this report we demonstrate that, in spite of all the antioxidant defences present in human plasma, its interaction with peroxynitrite leads to generation of free radical intermediates such as (i) the ascorbyl radical, detected by direct EPR, (ii) the albumin-thiyl radical, detected by spin-trapping experiments with both N-tert-butyl-alpha-phenylnitrone and 5,5-dimethyl-1-pyrroline N-oxide (DMPO), and (iii) a uric acid-derived free radical, detected as the DMPO radical adduct in plasma whose thiol groups were previously blocked with 5,5-dithiobis-(2-nitrobenzoic acid). The identity of the latter adduct was confirmed by parallel experiments demonstrating that it is not detectable in plasma pretreated with uricase, whereas it is formed in incubations of peroxynitrite with uric acid. Peroxynitrite-mediated oxidations were also followed by oxygen consumption and ascorbate and plasma-thiol depletion. Our results support the view that peroxynitrite-mediated one-electron oxidation of biomolecules may be an important event in its cytotoxic mechanism. In addition, the data have methodological implications by providing support for the use of EPR methodologies for monitoring both free radical reactions and ascorbate concentrations in biological fluids. PMID:8615782

  18. Cytokine and lipid mediator networks in tuberculosis

    PubMed Central

    Mayer-Barber, Katrin D.; Sher, Alan

    2014-01-01

    Summary A major approach for immunologic intervention in tuberculosis involves redirecting the outcome of the host immune response from the induction of disease to pathogen control. Cytokines and lipid mediators known as eicosanoids play key roles in regulating this balance and as such represent important targets for immunologic intervention. While the evidence for cytokine/eicosanoid function derives largely from the investigation of murine and zebra fish experimental infection models, clinical studies have confirmed the existence of many of the same pathways in tuberculosis patients. Here we summarize new data that reveal important intersections between the cytokine and eicosanoid networks in the host response to mycobacteria and discuss how targeting this crosstalk can promote resistance to lethal Mycobacterium tuberculosis infection. This approach could lead to new host-directed therapies to be used either as an adjunct for improving the efficacy of standard antibiotic treatment or for the management of drug-resistant infections. PMID:25703565

  19. Human inflammatory and resolving lipid mediator responses to resistance exercise and ibuprofen treatment

    PubMed Central

    Markworth, James F.; Vella, Luke; Lingard, Benjamin S.; Tull, Dedreia L.; Rupasinghe, Thusitha W.; Sinclair, Andrew J.; Maddipati, Krishna Rao

    2013-01-01

    Classical proinflammatory eicosanoids, and more recently discovered lipid mediators with anti-inflammatory and proresolving bioactivity, exert a complex role in the initiation, control, and resolution of inflammation. Using a targeted lipidomics approach, we investigated circulating lipid mediator responses to resistance exercise and treatment with the NSAID ibuprofen. Human subjects undertook a single bout of unaccustomed resistance exercise (80% of one repetition maximum) following oral ingestion of ibuprofen (400 mg) or placebo control. Venous blood was collected during early recovery (0–3 h and 24 h postexercise), and serum lipid mediator composition was analyzed by LC-MS-based targeted lipidomics. Postexercise recovery was characterized by elevated levels of cyclooxygenase (COX)-1 and 2-derived prostanoids (TXB2, PGE2, PGD2, PGF2α, and PGI2), lipooxygenase (5-LOX, 12-LOX, and 15-LOX)-derived hydroxyeicosatetraenoic acids (HETEs), and leukotrienes (e.g., LTB4), and epoxygenase (CYP)-derived epoxy/dihydroxy eicosatrienoic acids (EpETrEs/DiHETrEs). Additionally, we detected elevated levels of bioactive lipid mediators with anti-inflammatory and proresolving properties, including arachidonic acid-derived lipoxins (LXA4 and LXB4), and the EPA (E-series) and DHA (D-series)-derived resolvins (RvD1 and RvE1), and protectins (PD1 isomer 10S, 17S-diHDoHE). Ibuprofen treatment blocked exercise-induced increases in COX-1 and COX-2-derived prostanoids but also resulted in off-target reductions in leukotriene biosynthesis, and a diminished proresolving lipid mediator response. CYP pathway product metabolism was also altered by ibuprofen treatment, as indicated by elevated postexercise serum 5,6-DiHETrE and 8,9-DiHETrE only in those receiving ibuprofen. These findings characterize the blood inflammatory lipid mediator response to unaccustomed resistance exercise in humans and show that acute proinflammatory signals are mechanistically linked to the induction of a

  20. Distribution of bioactive lipid mediators in human skin.

    PubMed

    Kendall, Alexandra C; Pilkington, Suzanne M; Massey, Karen A; Sassano, Gary; Rhodes, Lesley E; Nicolaou, Anna

    2015-06-01

    The skin produces bioactive lipids that participate in physiological and pathological states, including homeostasis, induction, propagation, and resolution of inflammation. However, comprehension of the cutaneous lipid complement, and contribution to differing roles of the epidermal and dermal compartments, remains incomplete. We assessed the profiles of eicosanoids, endocannabinoids, N-acyl ethanolamides, and sphingolipids, in human dermis, epidermis, and suction blister fluid. We identified 18 prostanoids, 12 hydroxy-fatty acids, 9 endocannabinoids and N-acyl ethanolamides, and 21 non-hydroxylated ceramides and sphingoid bases, several demonstrating significantly different expression in the tissues assayed. The array of dermal and epidermal fatty acids was reflected in the lipid mediators produced, whereas similarities between lipid profiles in blister fluid and epidermis indicated a primarily epidermal origin of suction blister fluid. Supplementation with omega-3 fatty acids ex vivo showed that their action is mediated through perturbation of existing species and formation of other anti-inflammatory lipids. These findings demonstrate the diversity of lipid mediators involved in maintaining tissue homeostasis in resting skin and hint at their contribution to signaling, cross-support, and functions of different skin compartments. Profiling lipid mediators in biopsies and suction blister fluid can support studies investigating cutaneous inflammatory responses, dietary manipulation, and skin diseases lacking biomarkers and therapeutic targets.

  1. The expanding field of cannabimimetic and related lipid mediators

    PubMed Central

    Bradshaw, Heather B; Walker, J Michael

    2005-01-01

    The discovery of the endogenous cannabimimetic lipid mediators, anandamide and 2-arachidonoyl glycerol, opened the door to the discovery of other endogenous lipid mediators similar in structure and function. The majority of these compounds do not bind appreciably to known cannabinoid receptors; yet some of them produce cannabimimetic effects while others exert actions through novel mechanisms that remain to be elucidated. This review explores the growing diversity of recently discovered putative lipid mediators and their relationship to the endogenous cannabinoid system. The possibility that there remain many unidentified signalling lipids coupled with the evidence that many of these yield bioactive metabolites due to actions of known enzymes (e.g. cyclooxygenases, lipoxygenases, cytochrome P450s) suggests the existence of a large and complex family of lipid mediators about which only little is known at this time. The elucidation of the biochemistry and pharmacology of these compounds may provide therapeutic targets for a variety of conditions including sleep dysfunction, eating disorders, cardiovascular disease, as well as inflammation and pain. PMID:15655504

  2. Oleic acid-derived oleoylethanolamide: A nutritional science perspective.

    PubMed

    Bowen, Kate J; Kris-Etherton, Penny M; Shearer, Gregory C; West, Sheila G; Reddivari, Lavanya; Jones, Peter J H

    2017-04-04

    The fatty acid ethanolamide oleoylethanolamide (OEA) is an endogenous lipid mediator derived from the monounsaturated fatty acid, oleic acid. OEA is synthesized from membrane glycerophospholipids and is a high-affinity agonist of the nuclear transcription factor peroxisome proliferator-activated receptor α (PPAR-α). Dietary intake of oleic acid elevates circulating levels of OEA in humans by increasing substrate availability for OEA biosynthesis. Numerous clinical studies demonstrate a beneficial relationship between high-oleic acid diets and body composition, with emerging evidence to suggest OEA may mediate this response through modulation of lipid metabolism and energy intake. OEA exposure has been shown to stimulate fatty acid uptake, lipolysis, and β-oxidation, and also promote food intake control. Future research on high-oleic acid diets and body composition is warranted to confirm these outcomes and elucidate the underlying mechanisms by which oleic acid exerts its biological effects. These findings have significant practical implications, as the oleic acid-derived OEA molecule may be a promising therapeutic agent for weight management and obesity treatment.

  3. Liberating Chiral Lipid Mediators, Inflammatory Enzymes, and LIPID MAPS from Biological Grease

    PubMed Central

    Dennis, Edward A.

    2016-01-01

    In 1970, it was well accepted that the central role of lipids was in energy storage and metabolism, and it was assumed that amphipathic lipids simply served a passive structural role as the backbone of biological membranes. As a result, the scientific community was focused on nucleic acids, proteins, and carbohydrates as information-containing molecules. It took considerable effort until scientists accepted that lipids also “encode” specific and unique biological information and play a central role in cell signaling. Along with this realization came the recognition that the enzymes that act on lipid substrates residing in or on membranes and micelles must also have important signaling roles, spurring curiosity into their potentially unique modes of action differing from those acting on water-soluble substrates. This led to the creation of the concept of “surface dilution kinetics” for describing the mechanism of enzymes acting on lipid substrates, as well as the demonstration that lipid enzymes such as phospholipase A2 (PLA2) contain allosteric activator sites for specific phospholipids as well as for membranes. As our understanding of phospholipases advanced, so did the understanding that many of the lipids released by these enzymes are chiral information-containing signaling molecules; for example, PLA2 regulates the generation of precursors for the biosynthesis of eicosanoids and other bioactive lipid mediators of inflammation and resolution underlying disease progression. The creation of the LIPID MAPS initiative in 2003 and the ensuing development of the lipidomics field have revealed that lipid metabolites are central to human metabolism. Today lipids are recognized as key mediators of health and disease as we enter a new era of biomarkers and personalized medicine. This article is my personal “reflection” on these scientific advances. PMID:27555328

  4. Anti-Inflammatory and Pro-Resolving Lipid Mediators

    PubMed Central

    Serhan, Charles N.; Yacoubian, Stephanie; Yang, Rong

    2009-01-01

    The popular view that all lipid mediators are pro-inflammatory arises largely from the finding that non-steroidal anti-inflammatory drugs block the biosynthesis of prostaglandins. The resolution of inflammation was widely held to be a passive event until recently, with the characterization of novel biochemical pathways and lipid-derived mediators that are actively turned on in resolution possessing potent anti-inflammatory and pro-resolving actions. A lipid mediator informatics approach was employed to systematically identify new families of endogenous local-acting mediators from omega-3-polyunsaturated fatty acids (eicosapentaenoic acid and docosahexaenoic acid) in resolving exudates in addition to the lipoxins and aspirin-triggered lipoxins generated from arachidonic acid. These new chemical mediator families were coined resolvins and protectins, given their potent bioactions. In this annual review, we present recent advances on the biosynthesis and stereospecific actions of these new pro-resolving mediators, which have also proven to be organ protective and anti-fibrotic. PMID:18233953

  5. Intravenous fish oil lipid emulsion promotes a shift toward anti-inflammatory proresolving lipid mediators

    PubMed Central

    Kalish, Brian T.; Le, Hau D.; Fitzgerald, Jonathan M.; Wang, Samantha; Seamon, Kyle; Gura, Kathleen M.; Gronert, Karsten

    2013-01-01

    Parenteral nutrition (PN)-associated liver disease (PNALD) is a life-threatening complication of the administration of PN. The development of PNALD may be partly due to the composition of the lipid emulsion administered with PN: soybean oil-based lipid emulsions (SOLE) are associated with liver disease, while fish oil-based lipid emulsions (FOLE) are associated with prevention and improvement of liver disease. The objective of this study was to determine how the choice of lipid emulsion modified the production of bioactive lipid mediators (LMs). We utilized a mouse model of steatosis to study the differential effect of FOLE and SOLE. We subsequently validated these results in serum samples from a small cohort of human infants transitioning from SOLE to FOLE. In mice, FOLE was associated with production of anti-inflammatory, proresolving LMs; SOLE was associated with increased production of inflammatory LMs. In human infants, the transition from SOLE to FOLE was associated with a shift toward a proresolving lipidome. Together, these results demonstrate that the composition of the lipid emulsion directly modifies inflammatory homeostasis. PMID:24091595

  6. Ca-Mediated Electroformation of Cell-Sized Lipid Vesicles

    PubMed Central

    Tao, Fei; Yang, Peng

    2015-01-01

    Cell-sized lipid giant unilamellar vesicles (GUVs) are formed when lipid molecules self-assemble to construct a single bilayer compartment with similar morphology to living cells. The physics of self-assembly process is only generally understood and the size distribution of GUVs tends to be very polydisperse. Herein we report a strategy for the production of controlled size distributions of GUVs by a novel mechanism dissecting the mediation ability of calcium (Ca) on the conventional electroformation of GUVs. We finely construct both of the calcium ion (Ca2+) and calcium carbonate (CaCO3) mineral adsorption layers on a lipid film surface respectively during the electroformation of GUVs. It is found that Ca2+ Slip plane polarized by alternating electric field could induce a pattern of electroosmotic flow across the surface, and thus confine the fusion and growth of GUVs to facilitate the formation of uniform GUVs. The model is further improved by directly using CaCO3 that is in situ formed on a lipid film surface, providing a GUV population with narrow polydispersity. The two models deciphers the new biological function of calcium on the birth of cell-like lipid vesicles, and thus might be potentially relevant to the construction of new model to elucidate the cellular development process. PMID:25950604

  7. Lipoprotein mediated lipid uptake in oocytes of polychaetes (Annelida).

    PubMed

    Schenk, Sven; Hoeger, Ulrich

    2009-08-01

    The uptake of the 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI)-labeled sex-unspecific Nereis lipoprotein was investigated in oocytes of the nereidid polychaetes Nereis virens and Platynereis dumerilii. The fluorescence label was first observed in endocytic vesicles (<1 microm diameter), which later fused to larger vesicles (2-3 microm); these were finally incorporated into existing unlabeled yolk granules (5-6 microm). In Platynereis oocytes, the fusion of endocytic vesicles was delayed in oocytes at their final stage of development compared with those at an early stage of development. Lipoprotein double-labeled with fluorescein isothiocyanate (FITC) and DiI revealed that both the protein and the lipid moiety remained co-localized during incorporation into the yolk granules of the oocyte. No labeling of the cytoplasmic lipid droplets was observed. In N. virens, unlabeled Nereis lipoprotein was effective as a competitive inhibitor of DiI-labeled Nereis lipoprotein. Ligand blot experiments demonstrated the presence of a lipoprotein receptor with an apparent molecular mass of 120 kDa, which is different from that of the known yolk protein receptor. This indicates the presence, in the polychaete oocyte, of two distinct receptors mediating yolk protein and lipoprotein uptake, respectively. Thus, the sex-unspecific lipoprotein contributes to the lipid supply of the growing oocyte in addition to the known uptake of the yolk-protein-associated lipids. The absence of label in the cytoplasmic lipid droplets, even after prolonged incubation with labeled lipoprotein, suggests that these lipids arise either by the breakdown and resynthesis of lipoprotein-derived lipids and/or by de novo synthesis within the oocyte.

  8. Aspirin and lipid mediators in the cardiovascular system.

    PubMed

    Schrör, Karsten; Rauch, Bernhard H

    2015-09-01

    Aspirin is an unique compound because it bears two active moieties within one and the same molecule: a reactive acetyl group and the salicylate metabolite. Salicylate has some effects similar to aspirin, however only at higher concentrations, usually in the millimolar range, which are not obtained at conventional antiplatelet aspirin doses of 100-300 mg/day. Pharmacological actions of aspirin in the cardiovascular system at these doses are largely if not entirely due to target structure acetylation. Several classes of lipid mediators become affected: Best known is the cyclooxygenase-1 (COX-1) in platelets with subsequent inhibition of thromboxane and, possibly, thrombin formation. By this action, aspirin also inhibits paracrine thromboxane functions on other lipid mediators, such as the platelet storage product sphingosine-1-phosphate (S1P), an inflammatory mediator. Acetylation of COX-2 allows for generation of 15-(R)HETE and subsequent formation of "aspirin-triggered lipoxin" (ATL) by interaction with white cell lipoxygenases. In the cardiovascular system, aspirin also acetylates eNOS with subsequent upregulation of NO formation and enhanced expression of the antioxidans heme-oxygenase-1. This action is possibly also COX-2/ATL mediated. Many more acetylation targets have been identified in live cells by quantitative acid-cleavable activity-based protein profiling and might result in discovery of even more aspirin targets in the near future.

  9. Lipid Mediators in Aspirin-Exacerbated Respiratory Disease.

    PubMed

    Parker, Andrew R; Ayars, Andrew G; Altman, Matthew C; Henderson, William R

    2016-11-01

    Aspirin-exacerbated respiratory disease (AERD) is a syndrome of severe asthma and rhinosinusitis with nasal polyposis with exacerbations of baseline eosinophil-driven and mast cell-driven inflammation after nonsteroidal antiinflammatory drug ingestion. Although the underlying pathophysiology is poorly understood, dysregulation of the cyclooxygenase and 5-lipoxygenase pathways of arachidonic acid metabolism is thought to be key. Central features of AERD pathogenesis are overproduction of proinflammatory and bronchoconstrictor cysteinyl leukotrienes and prostaglandin (PG) D2 and inhibition of bronchoprotective and antiinflammatory PGE2. Imbalance in the ratio of these lipid mediators likely leads to the increased eosinophilic and mast cell inflammatory responses in the respiratory tract.

  10. Oxidized lipids and lipid-mediators are involved in cardiovascular injury induced by diesel exhaust particles and ozone

    EPA Science Inventory

    The mechanisms by which air pollutants induce cardiac and vascular injuries are unknown. We hypothesized that these injuries involve alterations in'aortic membrane lipids and lipid-mediators. We exposed male Wistar Kyoto rats (12-15 wk old), nose-only to air, ozone (03; 0.5 ppm),...

  11. Novel Lipid Mediators and Resolution Mechanisms in Acute Inflammation

    PubMed Central

    Serhan, Charles N.

    2010-01-01

    Because inflammation is appreciated as a unifying basis of many widely occurring diseases, the mechanisms involved in its natural resolution are of considerable interest. Using contained, self-limited inflammatory exudates and a systems approach, novel lipid-derived mediators and pathways were uncovered in the resolution of inflammatory exudates. These new families of local mediators control both the duration and magnitude of acute inflammation as well as the return of the site to homeostasis in the process of catabasis. This new genus of specialized proresolving mediators (SPM) includes essential fatty acid–derived lipoxins, resolvins, protectins, and, most recently, maresins. These families were named based on their unique structures and potent stereoselective actions. The temporally initiated biosynthesis of SPM and their direct impact on leukocyte trafficking and macrophage-directed clearance mechanisms provide clear evidence that resolution is an active, programmed response at the tissue level. Moreover, SPM that possess anti-inflammatory (ie, limiting PMN infiltration) and proresolving (enhance macrophage uptake and clearance of apoptotic PMN and microbial particles) actions as well as stimulating mucosal antimicrobial responses demonstrate that anti-inflammation and proresolution are different responses of the host and novel defining properties of these molecules. The mapping of new resolution circuits has opened the possibility for understanding mechanisms that lead from acute to chronic inflammation, or to the resolution thereof, as well as to potential, resolution-based immunopharmacological therapies. PMID:20813960

  12. Evaluation of Novel Polyunsaturated Fatty Acid Derived Lipid Mediators of Inflammation to Ameliorate the Deleterious Effects of Blast Overpressure on Eye and Brain Visual Processing Centers in Rats

    DTIC Science & Technology

    2013-10-01

    simulated blast overpressure waves the cellular, neuronal signaling, behavioral pathology of injuries to the eyes - specifically retina - and brain ...adult rat model of blast wave exposure, we rigorously characterized the cellular and functional damage to the eyes (retinas) and brain visual...strong relationship between the retina and brain optic tract cell damage (r = 0.8). Overall, our findings demonstrate that blast wave exposure leads

  13. Evaluation of Novel Polyunsaturated Fatty Acid Derived Lipid Mediators of Inflammation to Ameliorate the Deleterious Effects of Blast Overpressure on Eye and Brain Visual Processing Centers in Rats

    DTIC Science & Technology

    2014-10-01

    to high fidelity simulated blast over pressure waves (Friedlander waveform), as produced by a compressed air driven shock tube. Eye and brain ... brain , suggesting they have a rather limited potential as visual system therapeutics. 15. SUBJECT TERMS: Brain , eye, retina, blast wave , neuronal...face. It is also possible that the brain visual processing centers are being directly affected, since it is well established that blast wave exposure

  14. Silica nanoparticles to control the lipase-mediated digestion of lipid-based oral delivery systems.

    PubMed

    Tan, Angel; Simovic, Spomenka; Davey, Andrew K; Rades, Thomas; Boyd, Ben J; Prestidge, Clive A

    2010-04-05

    We investigate the role of hydrophilic fumed silica in controlling the digestion kinetics of lipid emulsions, hence further exploring the mechanisms behind the improved oral absorption of poorly soluble drugs promoted by silica-lipid hybrid (SLH) microcapsules. An in vitro lipolysis model was used to quantify the lipase-mediated digestion kinetics of a series of lipid vehicles formulated with caprylic/capric triglycerides: lipid solution, submicrometer lipid emulsions (in the presence and absence of silica), and SLH microcapsules. The importance of emulsification on lipid digestibility is evidenced by the significantly higher initial digestion rate constants for SLH microcapsules and lipid emulsions (>15-fold) in comparison with that of the lipid solution. Silica particles exerted an inhibitory effect on the digestion of submicrometer lipid emulsions regardless of their initial location, i.e., aqueous or lipid phases. This inhibitory effect, however, was not observed for SLH microcapsules. This highlights the importance of the matrix structure and porosity of the hybrid microcapsule system in enhancing lipid digestibility as compared to submicrometer lipid emulsions stabilized by silica. For each studied formulation, the digestion kinetics is well correlated to the corresponding in vivo plasma concentrations of a model drug, celecoxib, via multiple-point correlations (R(2) > 0.97). This supports the use of the lipid digestion model for predicting the in vivo outcome of an orally dosed lipid formulation. SLH microcapsules offer the potential to enhance the oral absorption of poorly soluble drugs via increased lipid digestibility in conjunction with improved drug dissolution/dispersion.

  15. Line tension at lipid phase boundaries as driving force for HIV fusion peptide-mediated fusion.

    PubMed

    Yang, Sung-Tae; Kiessling, Volker; Tamm, Lukas K

    2016-04-26

    Lipids and proteins are organized in cellular membranes in clusters, often called 'lipid rafts'. Although raft-constituent ordered lipid domains are thought to be energetically unfavourable for membrane fusion, rafts have long been implicated in many biological fusion processes. For the case of HIV gp41-mediated membrane fusion, this apparent contradiction can be resolved by recognizing that the interfaces between ordered and disordered lipid domains are the predominant sites of fusion. Here we show that line tension at lipid domain boundaries contributes significant energy to drive gp41-fusion peptide-mediated fusion. This energy, which depends on the hydrophobic mismatch between ordered and disordered lipid domains, may contribute tens of kBT to fusion, that is, it is comparable to the energy required to form a lipid stalk intermediate. Line-active compounds such as vitamin E lower line tension in inhomogeneous membranes, thereby inhibit membrane fusion, and thus may be useful natural viral entry inhibitors.

  16. Line tension at lipid phase boundaries as driving force for HIV fusion peptide-mediated fusion

    NASA Astrophysics Data System (ADS)

    Yang, Sung-Tae; Kiessling, Volker; Tamm, Lukas K.

    2016-04-01

    Lipids and proteins are organized in cellular membranes in clusters, often called `lipid rafts'. Although raft-constituent ordered lipid domains are thought to be energetically unfavourable for membrane fusion, rafts have long been implicated in many biological fusion processes. For the case of HIV gp41-mediated membrane fusion, this apparent contradiction can be resolved by recognizing that the interfaces between ordered and disordered lipid domains are the predominant sites of fusion. Here we show that line tension at lipid domain boundaries contributes significant energy to drive gp41-fusion peptide-mediated fusion. This energy, which depends on the hydrophobic mismatch between ordered and disordered lipid domains, may contribute tens of kBT to fusion, that is, it is comparable to the energy required to form a lipid stalk intermediate. Line-active compounds such as vitamin E lower line tension in inhomogeneous membranes, thereby inhibit membrane fusion, and thus may be useful natural viral entry inhibitors.

  17. Pseudomonas aeruginosa sabotages the generation of host proresolving lipid mediators.

    PubMed

    Flitter, Becca A; Hvorecny, Kelli L; Ono, Emiko; Eddens, Taylor; Yang, Jun; Kwak, Daniel H; Bahl, Christopher D; Hampton, Thomas H; Morisseau, Christophe; Hammock, Bruce D; Liu, Xinyu; Lee, Janet S; Kolls, Jay K; Levy, Bruce D; Madden, Dean R; Bomberger, Jennifer M

    2017-01-03

    Recurrent Pseudomonas aeruginosa infections coupled with robust, damaging neutrophilic inflammation characterize the chronic lung disease cystic fibrosis (CF). The proresolving lipid mediator, 15-epi lipoxin A4 (15-epi LXA4), plays a critical role in limiting neutrophil activation and tissue inflammation, thus promoting the return to tissue homeostasis. Here, we show that a secreted P. aeruginosa epoxide hydrolase, cystic fibrosis transmembrane conductance regulator inhibitory factor (Cif), can disrupt 15-epi LXA4 transcellular biosynthesis and function. In the airway, 15-epi LXA4 production is stimulated by the epithelial-derived eicosanoid 14,15-epoxyeicosatrienoic acid (14,15-EET). Cif sabotages the production of 15-epi LXA4 by rapidly hydrolyzing 14,15-EET into its cognate diol, eliminating a proresolving signal that potently suppresses IL-8-driven neutrophil transepithelial migration in vitro. Retrospective analyses of samples from patients with CF supported the translational relevance of these preclinical findings. Elevated levels of Cif in bronchoalveolar lavage fluid were correlated with lower levels of 15-epi LXA4, increased IL-8 concentrations, and impaired lung function. Together, these findings provide structural, biochemical, and immunological evidence that the bacterial epoxide hydrolase Cif disrupts resolution pathways during bacterial lung infections. The data also suggest that Cif contributes to sustained pulmonary inflammation and associated loss of lung function in patients with CF.

  18. Lipid membrane-mediated attraction between curvature inducing objects

    PubMed Central

    van der Wel, Casper; Vahid, Afshin; Šarić, Anđela; Idema, Timon; Heinrich, Doris; Kraft, Daniela J.

    2016-01-01

    The interplay of membrane proteins is vital for many biological processes, such as cellular transport, cell division, and signal transduction between nerve cells. Theoretical considerations have led to the idea that the membrane itself mediates protein self-organization in these processes through minimization of membrane curvature energy. Here, we present a combined experimental and numerical study in which we quantify these interactions directly for the first time. In our experimental model system we control the deformation of a lipid membrane by adhering colloidal particles. Using confocal microscopy, we establish that these membrane deformations cause an attractive interaction force leading to reversible binding. The attraction extends over 2.5 times the particle diameter and has a strength of three times the thermal energy (−3.3 kBT). Coarse-grained Monte-Carlo simulations of the system are in excellent agreement with the experimental results and prove that the measured interaction is independent of length scale. Our combined experimental and numerical results reveal membrane curvature as a common physical origin for interactions between any membrane-deforming objects, from nanometre-sized proteins to micrometre-sized particles. PMID:27618764

  19. Lipid membrane-mediated attraction between curvature inducing objects

    NASA Astrophysics Data System (ADS)

    van der Wel, Casper; Vahid, Afshin; Šarić, Anđela; Idema, Timon; Heinrich, Doris; Kraft, Daniela J.

    2016-09-01

    The interplay of membrane proteins is vital for many biological processes, such as cellular transport, cell division, and signal transduction between nerve cells. Theoretical considerations have led to the idea that the membrane itself mediates protein self-organization in these processes through minimization of membrane curvature energy. Here, we present a combined experimental and numerical study in which we quantify these interactions directly for the first time. In our experimental model system we control the deformation of a lipid membrane by adhering colloidal particles. Using confocal microscopy, we establish that these membrane deformations cause an attractive interaction force leading to reversible binding. The attraction extends over 2.5 times the particle diameter and has a strength of three times the thermal energy (‑3.3 kBT). Coarse-grained Monte-Carlo simulations of the system are in excellent agreement with the experimental results and prove that the measured interaction is independent of length scale. Our combined experimental and numerical results reveal membrane curvature as a common physical origin for interactions between any membrane-deforming objects, from nanometre-sized proteins to micrometre-sized particles.

  20. Effect of dietary alpha-linolenic fatty acid derived from chia when fed as ground seed, whole seed and oil on lipid content and fatty acid composition of rat plasma.

    PubMed

    Ayerza, Ricardo; Coates, Wayne

    2007-01-01

    Coronary heart disease (CHD) is the most common cause of death in the Western world. In both the USA and the EU it accounts for over 600,000 deaths yearly. Early data showing the benefits n-3 fatty acids provide in preventing CHD disease were obtained using 20:5n-3 and 22:6n-3 fatty acids derived from fish. Recently, however, it has been shown that reduced risks of CHD and other cardiovascular diseases are found with 18:3n-3 fatty acid as well. To determine if 18:3n-3 fatty acids positively influence plasma composition, 32 male Wistar rats were fed ad libitum four isocaloric diets with the energy derived from corn oil (T(1)), whole chia seed (T(2)), ground chia seed (T(3)), or chia oil (T(4)) for 30 days. At the end of the feeding period the rats were sacrificed, and blood samples were analyzed to determine serum CHOL, HDL, LDL, TG content, hemogram, and fatty acid composition. Chia decreased serum TG content and increased HDL content. Only with the T(2) diet was TG significantly (p < 0.05) lower, and only with the T(3) diet was HDL significantly (p < 0.05) higher, than the control diet. Chia significantly (p < 0.05) increased the 18:3n-3, 20:5n-3 and 22:6n-3 plasma contents compared to the control diet, with no significant (p < 0.05) difference among chia diets detected. Significant (p < 0.05) improvement in n-6/n-3 fatty acid ratio was observed for all chia diets when compared to the control.

  1. Duality of lipid mediators in host response against Mycobacterium tuberculosis: good cop, bad cop

    PubMed Central

    Dietzold, Jillian; Gopalakrishnan, Archana

    2015-01-01

    Lipid mediators play an important role in infection- and tissue injury-driven inflammatory responses and in the subsequent inhibition and resolution of the response. Here, we discuss recent findings that substantiate how Mycobacterium tuberculosis promotes its survival in the host by dysregulation of lipid mediator balance. By inhibiting prostaglandin E2 (PGE2) and enhancing lipoxin production, M. tuberculosis induces necrotic death of the macrophage, an environment that favors its growth. These new findings provide opportunities for developing and repurposing therapeutics to modulate lipid mediator balance and enhance M. tuberculosis growth restriction. PMID:25926980

  2. Protein-mediated transbilayer movement of lipids in eukaryotes and prokaryotes: the relevance of ABC transporters.

    PubMed

    Tannert, Astrid; Pohl, Antje; Pomorski, Thomas; Herrmann, Andreas

    2003-09-01

    Lipid distribution across cellular membranes is regulated by specific membrane proteins controlling transbilayer movement of lipids. Flippases facilitate flip-flop of lipids and allow them to equilibrate between the two membrane leaflets independent of ATP. Distinct P-Type-ATPases transport specific lipids unidirectionally across the membrane at the expense of ATP. A group of ATP-dependent lipid transporters, the ATP-binding cassette (ABC) transporter family, was identified in studies originally related to multidrug resistance (MDR) in cancer cells. Meanwhile, lipid transport activity has been shown for full and half size ABC proteins in eukaryotic and prokaryotic cells. This activity may not only modify the organisation of lipids in membranes, but could also be of significant consequence for cell homeostasis. The various types of lipid movement mediating proteins and their cellular localisation in eukaryotes and prokaryotes are reviewed.

  3. In Vivo Availability of Pro-Resolving Lipid Mediators in Oxazolone Induced Dermal Inflammation in the Mouse

    PubMed Central

    Homann, Julia; Suo, Jing; Schmidt, Mike; de Bruin, Natasja; Scholich, Klaus; Geisslinger, Gerd; Ferreirós, Nerea

    2015-01-01

    The activation and infiltration of polymorphonuclear neutrophils (PMN) are critical key steps in inflammation. PMN-mediated inflammation is limited by anti-inflammatory and pro-resolving mechanisms, including specialized pro-resolving lipid mediators (SPM). We examined the effects of 15-epi-LXA4 on inflammation and the biosynthesis of pro-inflammatory mediators, such as prostaglandins, leukotriene B4 and various hydroxyeicosatetraenoic acids and SPM, in an oxazolone (OXA)-induced hypersensitivity model for dermal inflammation. 15-epi-LXA4 (100 μM, 5 μL subcutaneously injected) significantly (P < 0.05) reduced inflammation in skin, 24 hours after the OXA challenge, as compared to skin treated with vehicle. No significant influence on the biosynthesis of prostaglandins or leukotriene B4 was observed, whereas the level of 15S-hydroxy-eicosatetraenoic acid was significantly (P < 0.05) lower in the skin areas treated with 15-epi-LXA4. In spite of the use of a fully validated analytical procedure, no SPM were detected in the biological samples. To investigate the reason for the lack of analytical signal, we tried to mimic the production of SPM (lipoxins, resolvins, maresin and protectin) by injecting them subcutaneously into the skin of mice and studying the in vivo availability and distribution of the compounds. All analytes showed very little lateral distribution in skin tissue and their levels were markedly decreased (> 95%) 2 hours after injection. However, docosahexaenoic acid derivatives were biologically more stable than SPM derived from arachidonic acid or eicosapentaenoic acid. PMID:26599340

  4. Counterion-mediated pattern formation in membranes containing anionic lipids

    PubMed Central

    Slochower, David R.; Wang, Yu-Hsiu; Tourdot, Richard W.; Radhakrishnan, Ravi; Janmey, Paul A.

    2014-01-01

    Most lipid components of cell membranes are either neutral, like cholesterol, or zwitterionic, like phosphatidylcholine and sphingomyelin. Very few lipids, such as sphingosine, are cationic at physiological pH. These generally interact only transiently with the lipid bilayer, and their synthetic analogs are often designed to destabilize the membrane for drug or DNA delivery. However, anionic lipids are common in both eukaryotic and prokaryotic cell membranes. The net charge per anionic phospholipid ranges from −1 for the most abundant anionic lipids such has phosphatidylserine, to near −7 for phosphatidylinositol 3,4,5 trisphosphate, although the effective charge depends on many environmental factors. Anionic phospholipids and other negatively charged lipids such as lipopolysaccharides are not randomly distributed in the lipid bilayer, but are highly restricted to specific leaflets of the bilayer and to regions near transmembrane proteins or other organized structures within the plane of the membrane. This review highlights some recent evidence that counterions, in the form of monovalent or divalent metal ions, polyamines, or cationic protein domains, have a large influence of the lateral distribution of anionic lipids within the membrane, and that lateral demixing of anionic lipids has effects on membrane curvature and protein function that are important for biological control. PMID:24556233

  5. Gene Expression of Proresolving Lipid Mediator Pathways Is Associated With Clinical Outcomes in Trauma Patients

    PubMed Central

    Orr, Sarah K.; Butler, Kathryn L.; Hayden, Douglas; Tompkins, Ronald G.; Serhan, Charles N.; Irimia, Daniel

    2015-01-01

    Objectives Specialized proresolving lipid mediators have emerged as powerful modulators of inflammation and activators of resolution. Animal models show significant benefits of specialized proresolving lipid mediators on survival and wound healing after major burn trauma. To date, no studies have investigated specialized proresolving lipid mediators and their relation to other lipid mediator pathways in humans after trauma. Here we determine if patients with poor outcomes after trauma have dysregulated lipid mediator pathways. Design We studied blood leukocyte expression of 18 genes critical to the synthesis, signaling, and metabolism of specialized proresolving lipid mediators and proinflammatory lipid mediators, and we correlated these expression patterns with clinical outcomes in trauma patients from the Inflammation and the Host Response to Injury study. Setting Seven U.S. medical trauma centers. Subjects Ninety-six patients enrolled in the Inflammation and Host Response to Injury study, after blunt trauma and unambiguously classified as having uncomplicated or complicated recoveries. Twenty-eight healthy volunteers were enrolled as controls. Interventions None. Measurements and Main Results Within each patient, the 18 genes of interest were used to calculate scores for distinct families of lipid mediators, including resolvins, lipoxins, prostaglandins, and leukotrienes, as well as leukotriene to resolvin score ratios. Scores were built using a simple weighting scheme, taking into consideration both dependent and independent activities of enzymes and receptors responsible for lipid mediator biosynthesis and function. Individually, ALOX12, PTGS2, PTGES, PTGDS, ALOX5AP, LTA4H, FPR2, PTGER2, LTB4R, HPGD, PTGR1, and CYP4F3 were expressed differentially over 28 days posttrauma between patients with uncomplicated and complicated recoveries (p < 0.05). When all genes were combined into scores, patients with uncomplicated recoveries had differential and higher resolvin

  6. Phloem proteomics reveals new lipid-binding proteins with a putative role in lipid-mediated signaling

    SciTech Connect

    Barbaglia, Allison M.; Tamot, Banita; Greve, Veronica; Hoffmann-Benning, Susanne

    2016-04-28

    Global climate changes inversely affect our ability to grow the food required for an increasing world population. To combat future crop loss due to abiotic stress, we need to understand the signals responsible for changes in plant development and the resulting adaptations, especially the signaling molecules traveling long-distance through the plant phloem. Using a proteomics approach, we had identified several putative lipid-binding proteins in the phloem exudates. Simultaneously, we identified several complex lipids as well as jasmonates. These findings prompted us to propose that phloem (phospho-) lipids could act as long-distance developmental signals in response to abiotic stress, and that they are released, sensed, and moved by phloem lipid-binding proteins (Benning et al., 2012). Indeed, the proteins we identified include lipases that could release a signaling lipid into the phloem, putative receptor components, and proteins that could mediate lipid-movement. To test this possible protein-based lipid-signaling pathway, three of the proteins, which could potentially act in a relay, are characterized here: (I) a putative GDSL-motif lipase (II) a PIG-P-like protein, with a possible receptor-like function; (III) and PLAFP (phloem lipid-associated family protein), a predicted lipid-binding protein of unknown function. Here we show that all three proteins bind lipids, in particular phosphatidic acid (PtdOH), which is known to participate in intracellular stress signaling. Genes encoding these proteins are expressed in the vasculature, a prerequisite for phloem transport. Cellular localization studies show that the proteins are not retained in the endoplasmic reticulum but surround the cell in a spotted pattern that has been previously observed with receptors and plasmodesmatal proteins. Abiotic signals that induce the production of PtdOH also regulate the expression of GDSL-lipase and PLAFP, albeit in opposite patterns. Our findings suggest that while all three

  7. Phloem proteomics reveals new lipid-binding proteins with a putative role in lipid-mediated signaling

    DOE PAGES

    Barbaglia, Allison M.; Tamot, Banita; Greve, Veronica; ...

    2016-04-28

    Global climate changes inversely affect our ability to grow the food required for an increasing world population. To combat future crop loss due to abiotic stress, we need to understand the signals responsible for changes in plant development and the resulting adaptations, especially the signaling molecules traveling long-distance through the plant phloem. Using a proteomics approach, we had identified several putative lipid-binding proteins in the phloem exudates. Simultaneously, we identified several complex lipids as well as jasmonates. These findings prompted us to propose that phloem (phospho-) lipids could act as long-distance developmental signals in response to abiotic stress, and thatmore » they are released, sensed, and moved by phloem lipid-binding proteins (Benning et al., 2012). Indeed, the proteins we identified include lipases that could release a signaling lipid into the phloem, putative receptor components, and proteins that could mediate lipid-movement. To test this possible protein-based lipid-signaling pathway, three of the proteins, which could potentially act in a relay, are characterized here: (I) a putative GDSL-motif lipase (II) a PIG-P-like protein, with a possible receptor-like function; (III) and PLAFP (phloem lipid-associated family protein), a predicted lipid-binding protein of unknown function. Here we show that all three proteins bind lipids, in particular phosphatidic acid (PtdOH), which is known to participate in intracellular stress signaling. Genes encoding these proteins are expressed in the vasculature, a prerequisite for phloem transport. Cellular localization studies show that the proteins are not retained in the endoplasmic reticulum but surround the cell in a spotted pattern that has been previously observed with receptors and plasmodesmatal proteins. Abiotic signals that induce the production of PtdOH also regulate the expression of GDSL-lipase and PLAFP, albeit in opposite patterns. Our findings suggest that while all

  8. Phloem Proteomics Reveals New Lipid-Binding Proteins with a Putative Role in Lipid-Mediated Signaling

    PubMed Central

    Barbaglia, Allison M.; Tamot, Banita; Greve, Veronica; Hoffmann-Benning, Susanne

    2016-01-01

    Global climate changes inversely affect our ability to grow the food required for an increasing world population. To combat future crop loss due to abiotic stress, we need to understand the signals responsible for changes in plant development and the resulting adaptations, especially the signaling molecules traveling long-distance through the plant phloem. Using a proteomics approach, we had identified several putative lipid-binding proteins in the phloem exudates. Simultaneously, we identified several complex lipids as well as jasmonates. These findings prompted us to propose that phloem (phospho-) lipids could act as long-distance developmental signals in response to abiotic stress, and that they are released, sensed, and moved by phloem lipid-binding proteins (Benning et al., 2012). Indeed, the proteins we identified include lipases that could release a signaling lipid into the phloem, putative receptor components, and proteins that could mediate lipid-movement. To test this possible protein-based lipid-signaling pathway, three of the proteins, which could potentially act in a relay, are characterized here: (I) a putative GDSL-motif lipase (II) a PIG-P-like protein, with a possible receptor-like function; (III) and PLAFP (phloem lipid-associated family protein), a predicted lipid-binding protein of unknown function. Here we show that all three proteins bind lipids, in particular phosphatidic acid (PtdOH), which is known to participate in intracellular stress signaling. Genes encoding these proteins are expressed in the vasculature, a prerequisite for phloem transport. Cellular localization studies show that the proteins are not retained in the endoplasmic reticulum but surround the cell in a spotted pattern that has been previously observed with receptors and plasmodesmatal proteins. Abiotic signals that induce the production of PtdOH also regulate the expression of GDSL-lipase and PLAFP, albeit in opposite patterns. Our findings suggest that while all three

  9. Conversion of α-linolenic acid to long-chain omega-3 fatty acid derivatives and alterations of HDL density subfractions and plasma lipids with dietary polyunsaturated fatty acids in Monk parrots (Myiopsitta monachus).

    PubMed

    Petzinger, C; Larner, C; Heatley, J J; Bailey, C A; MacFarlane, R D; Bauer, J E

    2014-04-01

    The effect of α-linolenic acid from a flaxseed (FLX)-enriched diet on plasma lipid and fatty acid metabolism and possible atherosclerosis risk factors was studied in Monk parrots (Myiopsitta monachus). Twenty-four Monk parrots were randomly assigned to diets containing either 10% ground SUNs or 10% ground FLXs. Feed intake was calculated daily. Blood samples, body condition scores and body weights were obtained at -5 weeks, day 0, 7, 14, 28, 42 and 70. Plasma samples were analysed for total cholesterol, free cholesterol, triacylglycerols and lipoproteins. Phospholipid subfraction fatty acid profiles were determined. By day 70, the FLX group had significantly higher plasma phospholipid fatty acids including 18:3n-3 (α-linolenic acid), 20:5n-3 (eicosapentaenoic acid) and 22:6n-3 (docosahexaenoic acid). The sunflower group had significantly higher plasma phospholipid levels of 20:4n-6 (arachidonic acid). By day 70, the high-density lipoprotein (HDL) peak shifted resulting in significantly different HDL peak densities between the two experimental groups (1.097 g/ml FLX group and 1.095 g/ml SUN group, p = 0.028). The plasma fatty acid results indicate that Monk parrots can readily convert α-linolenic acid to the long-chain omega-3 derivatives including docosahexaenoic acid and reduce 20:4n-6 accumulation in plasma phospholipids. The reason for a shift in the HDL peak density is unknown at this time.

  10. Structure-activity relationship in cationic lipid mediated gene transfection.

    PubMed

    Niculescu-Duvaz, Dan; Heyes, James; Springer, Caroline J

    2003-07-01

    Non-viral synthetic vectors for gene delivery represent a safer alternative to viral vectors. Their main drawback is the low transfection efficiency, especially in vivo. Among the non-viral vectors currently in use, the cationic liposomes composed of cationic lipids are the most common. This review discusses the physicochemical properties of cationic lipids, the formation, macrostructure and specific parameters of the corresponding formulated liposomes, and the effect of all these parameters on transfection efficiency. The optimisation of liposomal vectors requires both the understanding of the biological variables involved in the transfection process, and the effect of the structural elements of the cationic lipids on these biological variables. The biological barriers relevant for in vitro and in vivo transfection are identified, and solutions to overcome them based on rational design of the cationic lipids are discussed. The review focuses on the relationship between the structure of the cationic lipid and the transfection activity. The structure is analysed in a modular manner. The hydrophobic domain, the cationic head group, the backbone that acts as a scaffold for the other domains, the linkers between backbone, hydrophobic domain and cationic head group, the polyethyleneglycol chains and the targeting moiety are identified as distinct elements of the cationic lipids used in gene therapy. The main chemical functionalities used to built these domains, as well as overall molecular features such as architecture and geometry, are presented. Studies of structure-activity relationships of each cationic lipid domain, including the authors', and the trends identified by these studies, help furthering the understanding of the mechanism governing the formation and behaviour of cationic liposomes in gene delivery, and therefore the rational design of new improved cationic lipids vectors capable of achieving clinical significance.

  11. The TULIP superfamily of eukaryotic lipid-binding proteins as a mediator of lipid sensing and transport.

    PubMed

    Alva, Vikram; Lupas, Andrei N

    2016-08-01

    The tubular lipid-binding (TULIP) superfamily has emerged in recent years as a major mediator of lipid sensing and transport in eukaryotes. It currently encompasses three protein families, SMP-like, BPI-like, and Takeout-like, which share a common fold. This fold consists of a long helix wrapped in a highly curved anti-parallel β-sheet, enclosing a central, lipophilic cavity. The SMP-like proteins, which include subunits of the ERMES complex and the extended synaptotagmins (E-Syts), appear to be mainly located at membrane contacts sites (MCSs) between organelles, mediating inter-organelle lipid exchange. The BPI-like proteins, which include the bactericidal/permeability-increasing protein (BPI), the LPS (lipopolysaccharide)-binding protein (LBP), the cholesteryl ester transfer protein (CETP), and the phospholipid transfer protein (PLTP), are either involved in innate immunity against bacteria through their ability to sense lipopolysaccharides, as is the case for BPI and LBP, or in lipid exchange between lipoprotein particles, as is the case for CETP and PLTP. The Takeout-like proteins, which are comprised of insect juvenile hormone-binding proteins and arthropod allergens, transport, where known, lipid hormones to target tissues during insect development. In all cases, the activity of these proteins is underpinned by their ability to bind large, hydrophobic ligands in their central cavity and segregate them away from the aqueous environment. Furthermore, where they are involved in lipid exchange, recent structural studies have highlighted their ability to establish lipophilic, tubular channels, either between organelles in the case of SMP domains or between lipoprotein particles in the case of CETP. Here, we review the current knowledge on the structure, versatile functions, and evolution of the TULIP superfamily. We propose a deep evolutionary split in this superfamily, predating the Last Eukaryotic Common Ancestor, between the SMP-like proteins, which act on

  12. Drosophila Lipophorin Receptors Recruit the Lipoprotein LTP to the Plasma Membrane to Mediate Lipid Uptake

    PubMed Central

    Rodríguez-Vázquez, Míriam; Mejía-Morales, John E.; Culi, Joaquim

    2015-01-01

    Lipophorin, the main Drosophila lipoprotein, circulates in the hemolymph transporting lipids between organs following routes that must adapt to changing physiological requirements. Lipophorin receptors expressed in developmentally dynamic patterns in tissues such as imaginal discs, oenocytes and ovaries control the timing and tissular distribution of lipid uptake. Using an affinity purification strategy, we identified a novel ligand for the lipophorin receptors, the circulating lipoprotein Lipid Transfer Particle (LTP). We show that specific isoforms of the lipophorin receptors mediate the extracellular accumulation of LTP in imaginal discs and ovaries. The interaction requires the LA-1 module in the lipophorin receptors and is strengthened by a contiguous region of 16 conserved amino acids. Lipophorin receptor variants that do not interact with LTP cannot mediate lipid uptake, revealing an essential role of LTP in the process. In addition, we show that lipophorin associates with the lipophorin receptors and with the extracellular matrix through weak interactions. However, during lipophorin receptor-mediated lipid uptake, LTP is required for a transient stabilization of lipophorin in the basolateral plasma membrane of imaginal disc cells. Together, our data suggests a molecular mechanism by which the lipophorin receptors tether LTP to the plasma membrane in lipid acceptor tissues. LTP would interact with lipophorin particles adsorbed to the extracellular matrix and with the plasma membrane, catalyzing the exchange of lipids between them. PMID:26121667

  13. Lipid rafts mediate ultraviolet light-induced Fas aggregation in M624 melanoma cells.

    PubMed

    Elyassaki, Walid; Wu, Shiyong

    2006-01-01

    Ultraviolet light (UV) induces aggregation of Fas-receptor through a Fas-ligand-independent pathway. However, the mechanism of ultraviolet light-induced Fas-receptor aggregation is not known. In this report, we show that lipid rafts mediate ultraviolet light-induced aggregation of Fas. Our data show that UV induces a redistribution of Fas-receptor in a 25-5% Optiprep continuous gradient. The amount of Fas-receptorS is significantly increased in a gradient fraction that contain lipid rafts and is associated with an increase of FADD and caspase-8. Our data also show that the active dimeric form of caspase-8 (p44/p41) is increased in the lipid raft fraction. In addition, our data show that cholesterol, a major component of lipid rafts, is significantly reduced in only the lipid raft fractions after UV-irradiation. However, ceramide, another major lipid raft component, is increased evenly in all gradient fractions after UV-irradiation. These results suggest that UV alters the composition of major lipid raft components, which leads to the recruitment of Fas-receptor and FADD, with subsequent activation of caspase-8. Based on our results, we propose a novel mechanism by which UV induces apoptosis through a membrane lipid raft-mediated signaling pathway.

  14. Signal Integration by Lipid-Mediated Spatial Cross Talk between Ras Nanoclusters

    PubMed Central

    Zhou, Yong; Liang, Hong; Rodkey, Travis; Ariotti, Nicholas; Parton, Robert G.

    2014-01-01

    Lipid-anchored Ras GTPases form transient, spatially segregated nanoclusters on the plasma membrane that are essential for high-fidelity signal transmission. The lipid composition of Ras nanoclusters, however, has not previously been investigated. High-resolution spatial mapping shows that different Ras nanoclusters have distinct lipid compositions, indicating that Ras proteins engage in isoform-selective lipid sorting and accounting for different signal outputs from different Ras isoforms. Phosphatidylserine is a common constituent of all Ras nanoclusters but is only an obligate structural component of K-Ras nanoclusters. Segregation of K-Ras and H-Ras into spatially and compositionally distinct lipid assemblies is exquisitely sensitive to plasma membrane phosphatidylserine levels. Phosphatidylserine spatial organization is also modified by Ras nanocluster formation. In consequence, Ras nanoclusters engage in remote lipid-mediated communication, whereby activated H-Ras disrupts the assembly and operation of spatially segregated K-Ras nanoclusters. Computational modeling and experimentation reveal that complex effects of caveolin and cortical actin on Ras nanoclustering are similarly mediated through regulation of phosphatidylserine spatiotemporal dynamics. We conclude that phosphatidylserine maintains the lateral segregation of diverse lipid-based assemblies on the plasma membrane and that lateral connectivity between spatially remote lipid assemblies offers important previously unexplored opportunities for signal integration and signal processing. PMID:24366544

  15. Lipid and polymeric carrier-mediated nucleic acid delivery

    PubMed Central

    Zhu, Lin; Mahato, Ram I

    2010-01-01

    Importance of the field Nucleic acids such as plasmid DNA, antisense oligonucleotide, and RNA interference (RNAi) molecules, have a great potential to be used as therapeutics for the treatment of various genetic and acquired diseases. To design a successful nucleic acid delivery system, the pharmacological effect of nucleic acids, the physiological condition of the subjects or sites, and the physicochemical properties of nucleic acid and carriers have to be thoroughly examined. Areas covered in this review The commonly used lipids, polymers and corresponding delivery systems are reviewed in terms of their characteristics, applications, advantages and limitations. What the reader will gain This article aims to provide an overview of biological barriers and strategies to overcome these barriers by properly designing effective synthetic carriers for nucleic acid delivery. Take home message A thorough understanding of biological barriers and the structure–activity relationship of lipid and polymeric carriers is the key for effective nucleic acid therapy. PMID:20836625

  16. Synthesis of Lipid Mediators during UVB-Induced Inflammatory Hyperalgesia in Rats and Mice

    PubMed Central

    Sisignano, Marco; Angioni, Carlo; Ferreiros, Nerea; Schuh, Claus-Dieter; Suo, Jing; Schreiber, Yannick; Dawes, John M.; Antunes-Martins, Ana; Bennett, David L. H.; McMahon, Stephen B.; Geisslinger, Gerd; Scholich, Klaus

    2013-01-01

    Peripheral sensitization during inflammatory pain is mediated by a variety of endogenous proalgesic mediators including a number of oxidized lipids, some of which serve endogenous modulators of sensory TRP-channels. These lipids are eicosanoids of the arachidonic acid and linoleic acid pathway, as well as lysophophatidic acids (LPAs). However, their regulation pattern during inflammatory pain and their contribution to peripheral sensitization is still unclear. Here, we used the UVB-model for inflammatory pain to investigate alterations of lipid concentrations at the site of inflammation, the dorsal root ganglia (DRGs) as well as the spinal dorsal horn and quantified 21 lipid species from five different lipid families at the peak of inflammation 48 hours post irradiation. We found that known proinflammatory lipids as well as lipids with unknown roles in inflammatory pain to be strongly increased in the skin, whereas surprisingly little changes of lipid levels were seen in DRGs or the dorsal horn. Importantly, although there are profound differences between the number of cytochrome (CYP) genes between mice and rats, CYP-derived lipids were regulated similarly in both species. Since TRPV1 agonists such as LPA 18∶1, 9- and 13-HODE, 5- and 12-HETE were elevated in the skin, they may contribute to thermal hyperalgesia and mechanical allodynia during UVB-induced inflammatory pain. These results may explain why some studies show relatively weak analgesic effects of cyclooxygenase inhibitors in UVB-induced skin inflammation, as they do not inhibit synthesis of other proalgesic lipids such as LPA 18∶1, 9-and 13-HODE and HETEs. PMID:24349046

  17. Reversal of intramyocellular lipid accumulation by lipophagy and a p62-mediated pathway

    PubMed Central

    Lam, T; Harmancey, R; Vasquez, H; Gilbert, B; Patel, N; Hariharan, V; Lee, A; Covey, M; Taegtmeyer, H

    2016-01-01

    We have previously observed the reversal of lipid droplet deposition in skeletal muscle of morbidly obese patients following bariatric surgery. We now investigated whether activation of autophagy is the mechanism underlying this observation. For this purpose, we incubated rat L6 myocytes over a period of 6 days with long-chain fatty acids (an equimolar, 1.0 mM, mixture of oleate and palmitate in the incubation medium). At day 6, the autophagic inhibitor (bafilomycin A1, 200 nM) and the autophagic activator (rapamycin, 1 μM) were added separately or in combination for 48 h. Intracellular triglyceride (TG) accumulation was visualized and quantified colorimetrically. Protein markers of autophagic flux (LC3 and p62) and cell death (caspase-3 cleavage) were measured by immunoblotting. Inhibition of autophagy by bafilomycin increased TG accumulation and also increased lipid-mediated cell death. Conversely, activation of autophagy by rapamycin reduced both intracellular lipid accumulation and cell death. Unexpectedly, treatment with both drugs added simultaneously resulted in decreased lipid accumulation. In this treatment group, immunoblotting revealed p62 degradation (autophagic flux), immunofluorescence revealed the colocalization of p62 with lipid droplets, and co-immunoprecipitation confirmed the interaction of p62 with ADRP (adipose differentiation-related protein), a lipid droplet membrane protein. Thus the association of p62 with lipid droplet turnover suggests a novel pathway for the breakdown of lipid droplets in muscle cells. In addition, treatment with rapamycin and bafilomycin together also suggested the export of TG into the extracellular space. We conclude that lipophagy promotes the clearance of lipids from myocytes and switches to an alternative, p62-mediated, lysosomal-independent pathway in the context of chronic lipid overload (*P<0.05, **P<0.01, ***P<0.001, ****P<0.0001). PMID:27625792

  18. Modulation of the Activities of Neuronal Ion Channels by Fatty Acid-Derived Pro-Resolvents

    PubMed Central

    Choi, Geunyeol; Hwang, Sun Wook

    2016-01-01

    Progress of inflammation depends on the balance between two biological mechanisms: pro-inflammatory and pro-resolving processes. Many extracellular and intracellular molecular components including cytokines, growth factors, steroids, neurotransmitters, and lipidergic mediators and their receptors contribute to the two processes, generated from cellular participants during inflammation. Fatty acid-derived mediators are crucial in directing the inflammatory phase and orchestrating heterogeneous reactions of participants such as inflamed cells, innate immune cells, vascular components, innervating neurons, etc. As well as activating specific types of receptor molecules, lipidergic mediators can actively control the functions of various ion channels via direct binding and/or signal transduction, thereby altering cellular functions. Lipid mediators can be divided into two classes based on which of the two processes they promote: pro-inflammatory, which includes prostaglandins and leukotrienes, and pro-resolving, which includes lipoxins, resolvins, and maresins. The research on the modulations of neuronal ion channels regarding the actions of the pro-inflammatory class has begun relatively earlier while the focus is currently expanding to cover the ion channel interaction with pro-resolvents. As a result, knowledge of inhibitory mechanisms by the pro-resolvents, historically seldom found for other known endogenous modulators or pro-inflammatory mediators, is accumulating particularly upon sensory neuronal cation channels. Diverse mechanistic explanations at molecular levels are being proposed and refined. Here we overviewed the interactions of lipidergic pro-resolvents with neuronal ion channels and outcomes from the interactions, focusing on transient receptor potential (TRP) ion channels. We also discuss unanswered hypotheses and perspectives regarding their interactions. PMID:27877134

  19. Novel cajaninstilbene acid derivatives as antibacterial agents.

    PubMed

    Geng, Zhi-Zhong; Zhang, Jian-Jun; Lin, Jing; Huang, Mei-Yan; An, Lin-Kun; Zhang, Hong-Bin; Sun, Ping-Hua; Ye, Wen-Cai; Chen, Wei-Min

    2015-07-15

    Discovery of novel antibacterial agents with new structural scaffolds that combat drug-resistant pathogens is an urgent task. Cajaninstilbene acid, which is isolated from pigeonpea leaves, has shown antibacterial activity. In this study, a series of cajaninstilbene acid derivatives were designed and synthesized. The antibacterial activities of these compounds against gram-negative and gram-positive bacteria, as well as nine strains of methicillin-resistant staphylococcus aureus (MRSA) bacteria are evaluated,and the related structure-activity relationships are discussed. Assays suggest that some of the synthetic cajaninstilbene acid derivatives exhibit potent antibacterial activity against gram-positive bacterial strains and MRSA. Among these compounds, 5b, 5c, 5j and 5k show better antibacterial activity than the positive control compounds. The results of MTT assays illustrate the low cytotoxicity of the active compounds.

  20. Kinetics of enzyme-mediated hydrolysis of lipid vesicles

    NASA Astrophysics Data System (ADS)

    Zhdanov, Vladimir P.; Agnarsson, Björn; Höök, Fredrik

    2016-10-01

    Membrane enzymatic reactions can now be experimentally studied at the level of single sub-100 nm lipid vesicles. To interpret such experiments, we scrutinize theoretically various aspects of the hydrolysis of vesicles by single enzyme molecules and enzyme (e.g., PLA2) supplied with the constant rate. Using the mean-field kinetic model, we illustrate the shape of the corresponding kinetics and the dependence of the time scale of the reaction on the vesicle radius. Stochastic effects are illustrated as well. In addition, we discuss the likely mechanisms of the reaction-induced pore formation and bilayer rupture.

  1. The Role of Lipid Competition for Endosymbiont-Mediated Protection against Parasitoid Wasps in Drosophila

    PubMed Central

    Schüpfer, Fanny

    2016-01-01

    ABSTRACT Insects commonly harbor facultative bacterial endosymbionts, such as Wolbachia and Spiroplasma species, that are vertically transmitted from mothers to their offspring. These endosymbiontic bacteria increase their propagation by manipulating host reproduction or by protecting their hosts against natural enemies. While an increasing number of studies have reported endosymbiont-mediated protection, little is known about the mechanisms underlying this protection. Here, we analyze the mechanisms underlying protection from parasitoid wasps in Drosophila melanogaster mediated by its facultative endosymbiont Spiroplasma poulsonii. Our results indicate that S. poulsonii exerts protection against two distantly related wasp species, Leptopilina boulardi and Asobara tabida. S. poulsonii-mediated protection against parasitoid wasps takes place at the pupal stage and is not associated with an increased cellular immune response. In this work, we provide three important observations that support the notion that S. poulsonii bacteria and wasp larvae compete for host lipids and that this competition underlies symbiont-mediated protection. First, lipid quantification shows that both S. poulsonii and parasitoid wasps deplete D. melanogaster hemolymph lipids. Second, the depletion of hemolymphatic lipids using the Lpp RNA interference (Lpp RNAi) construct reduces wasp success in larvae that are not infected with S. poulsonii and blocks S. poulsonii growth. Third, we show that the growth of S. poulsonii bacteria is not affected by the presence of the wasps, indicating that when S. poulsonii is present, larval wasps will develop in a lipid-depleted environment. We propose that competition for host lipids may be relevant to endosymbiont-mediated protection in other systems and could explain the broad spectrum of protection provided. PMID:27406568

  2. OSBP-Related Protein Family: Mediators of Lipid Transport and Signaling at Membrane Contact Sites.

    PubMed

    Kentala, Henriikka; Weber-Boyvat, Marion; Olkkonen, Vesa M

    2016-01-01

    Oxysterol-binding protein (OSBP) and its related protein homologs, ORPs, constitute a conserved family of lipid-binding/transfer proteins (LTPs) expressed ubiquitously in eukaryotes. The ligand-binding domain of ORPs accommodates cholesterol and oxysterols, but also glycerophospholipids, particularly phosphatidylinositol-4-phosphate (PI4P). ORPs have been implicated as intracellular lipid sensors or transporters. Most ORPs carry targeting determinants for the endoplasmic reticulum (ER) and non-ER organelle membrane. ORPs are located and function at membrane contact sites (MCSs), at which ER is closely apposed with other organelle limiting membranes. Such sites have roles in lipid transport and metabolism, control of Ca(2+) fluxes, and signaling events. ORPs are postulated either to transport lipids over MCSs to maintain the distinct lipid compositions of organelle membranes, or to control the activity of enzymes/protein complexes with functions in signaling and lipid metabolism. ORPs may transfer PI4P and another lipid class bidirectionally. Transport of PI4P followed by its hydrolysis would in this model provide the energy for transfer of the other lipid against its concentration gradient. Control of organelle lipid compositions by OSBP/ORPs is important for the life cycles of several pathogenic viruses. Targeting ORPs with small-molecular antagonists is proposed as a new strategy to combat viral infections. Several ORPs are reported to modulate vesicle transport along the secretory or endocytic pathways. Moreover, antagonists of certain ORPs inhibit cancer cell proliferation. Thus, ORPs are LTPs, which mediate interorganelle lipid transport and coordinate lipid signals with a variety of cellular regimes.

  3. Resolvins, specialized proresolving lipid mediators, and their potential roles in metabolic diseases.

    PubMed

    Spite, Matthew; Clària, Joan; Serhan, Charles N

    2014-01-07

    Inflammation is associated with the development of diseases characterized by altered nutrient metabolism. Although an acute inflammatory response is host-protective and normally self-limited, chronic low-grade inflammation associated with metabolic diseases is sustained and detrimental. The resolution of inflammation involves the termination of neutrophil recruitment, counterregulation of proinflammatory mediators, stimulation of macrophage-mediated clearance, and tissue remodeling. Specialized proresolving lipid mediators (SPMs)-resolvins, protectins, and maresins-are novel autacoids that resolve inflammation, protect organs, and stimulate tissue regeneration. Here, we review evidence that the failure of resolution programs contributes to metabolic diseases and that SPMs may play pivotal roles in their resolution.

  4. Morphogenesis of protrusions from confined lipid bilayers mediated by mechanics

    NASA Astrophysics Data System (ADS)

    Arroyo, Marino; Staykova, Margarita; Rahimi, Mohammad; Stone, Howard A.

    2012-02-01

    Biological membranes adopt a wide range of shapes that structure and give functionality to cells, compartmentalizing the cytosol, forming organelles, or regulating their area. The formation, stabilization, and remodeling of these structures is generally attributed to localized forces or to biochemical processes (insertion of proteins, active compositional regulation). Noting that in the crowded intra and extra-cellular environments membranes are highly constrained, we explore to what extent can mechanics explain the shape of protrusions out of confined membranes. For this purpose, we developed an in-vitro system coupling a lipid bilayer to the strain-controlled deformation of an elastic sheet (Staykova et al, PNAS 108, 2011). We show that upon contracting the elastic support, tubular or spherical protrusions grow out of the adhered membrane, which can be reversibly controlled with strain and osmolarity without resorting to localized forces or chemical alterations of the bilayer. The morphologies produced by our minimal system are ubiquitous in cells, suggesting mechanics may be a simple and generic organizing principle. We can understand most of our observations in terms of a phase diagram accounting for elasticity, adhesion, and the limited amount of area and volume available.

  5. 40 CFR 721.6097 - Phosphoric acid derivative (generic name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phosphoric acid derivative (generic... Specific Chemical Substances § 721.6097 Phosphoric acid derivative (generic name). (a) Chemical substance... phosphoric acid derivative (PMN P-95-284) is subject to reporting under this section for the significant...

  6. 40 CFR 721.6097 - Phosphoric acid derivative (generic name).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phosphoric acid derivative (generic... Specific Chemical Substances § 721.6097 Phosphoric acid derivative (generic name). (a) Chemical substance... phosphoric acid derivative (PMN P-95-284) is subject to reporting under this section for the significant...

  7. 40 CFR 721.6097 - Phosphoric acid derivative (generic name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Phosphoric acid derivative (generic... Specific Chemical Substances § 721.6097 Phosphoric acid derivative (generic name). (a) Chemical substance... phosphoric acid derivative (PMN P-95-284) is subject to reporting under this section for the significant...

  8. 40 CFR 721.6097 - Phosphoric acid derivative (generic name).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phosphoric acid derivative (generic... Specific Chemical Substances § 721.6097 Phosphoric acid derivative (generic name). (a) Chemical substance... phosphoric acid derivative (PMN P-95-284) is subject to reporting under this section for the significant...

  9. 40 CFR 721.6097 - Phosphoric acid derivative (generic name).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Phosphoric acid derivative (generic... Specific Chemical Substances § 721.6097 Phosphoric acid derivative (generic name). (a) Chemical substance... phosphoric acid derivative (PMN P-95-284) is subject to reporting under this section for the significant...

  10. Opt2 mediates the exposure of phospholipids during cellular adaptation to altered lipid asymmetry.

    PubMed

    Yamauchi, Saori; Obara, Keisuke; Uchibori, Kenya; Kamimura, Akiko; Azumi, Kaoru; Kihara, Akio

    2015-01-01

    Plasma membrane lipid asymmetry is important for various membrane-associated functions and is regulated by membrane proteins termed flippases and floppases. The Rim101 pathway senses altered lipid asymmetry in the yeast plasma membrane. The mutant lem3Δ cells, in which lipid asymmetry is disturbed owing to the inactivation of the plasma membrane flippases, showed a severe growth defect when the Rim101 pathway was impaired. To identify factors involved in the Rim101-pathway-dependent adaptation to altered lipid asymmetry, we performed DNA microarray analysis and found that Opt2 induced by the Rim101 pathway plays an important role in the adaptation to altered lipid asymmetry. Biochemical investigation of Opt2 revealed its localization to the plasma membrane and the Golgi, and provided several lines of evidence for the Opt2-mediated exposure of phospholipids. In addition, Opt2 was found to be required for the maintenance of vacuolar morphology and polarized cell growth. These results suggest that Opt2 is a novel factor involved in cell homeostasis by regulating lipid asymmetry.

  11. Enzymatic synthesis of cinnamic acid derivatives.

    PubMed

    Lee, Gia-Sheu; Widjaja, Arief; Ju, Yi-Hsu

    2006-04-01

    Using Novozym 435 as catalyst, the syntheses of ethyl ferulate (EF) from ferulic acid (4-hydroxy 3-methoxy cinnamic acid) and ethanol, and octyl methoxycinnamate (OMC) from p-methoxycinnamic acid and 2-ethyl hexanol were successfully carried out in this study. A conversion of 87% was obtained within 2 days at 75 degrees C for the synthesis of EF. For the synthesis of OMC at 80 degrees C, 90% conversion can be obtained within 1 day. The use of solvent and high reaction temperature resulted in better conversion for the synthesis of cinnamic acid derivatives. Some cinnamic acid esters could also be obtained with higher conversion and shorter reaction times in comparison to other methods reported in the literature. The enzyme can be reused several times before significant activity loss was observed.

  12. Lipid Raft-Mediated Regulation of Hyaluronan–CD44 Interactions in Inflammation and Cancer

    PubMed Central

    Murai, Toshiyuki

    2015-01-01

    Hyaluronan is a major component of the extracellular matrix and plays pivotal roles in inflammation and cancer. Hyaluronan oligomers are frequently found in these pathological conditions, in which they exert their effects via association with the transmembrane receptor CD44. Lipid rafts are cholesterol- and glycosphingolipid-enriched membrane microdomains that may regulate membrane receptors while serving as platforms for transmembrane signaling at the cell surface. This article focuses on the recent discovery that lipid rafts regulate the interaction between CD44 and hyaluronan, which depends largely on hyaluronan’s size. Lipid rafts regulate CD44’s ability to bind hyaluronan in T cells, control the rolling adhesion of lymphocytes on vascular endothelial cells, and regulate hyaluronan- and CD44-mediated cancer cell migration. The implications of these findings for preventing inflammatory disorders and cancer are also discussed. PMID:26347743

  13. Lipid Geometry and Bilayer Curvature Modulate LC3/GABARAP-Mediated Model Autophagosomal Elongation

    PubMed Central

    Landajuela, Ane; Hervás, Javier H.; Antón, Zuriñe; Montes, L. Ruth; Gil, David; Valle, Mikel; Rodriguez, J. Francisco; Goñi, Felix M.; Alonso, Alicia

    2016-01-01

    Autophagy, an important catabolic pathway involved in a broad spectrum of human diseases, implies the formation of double-membrane-bound structures called autophagosomes (AP), which engulf material to be degraded in lytic compartments. How APs form, especially how the membrane expands and eventually closes upon itself, is an area of intense research. Ubiquitin-like ATG8 has been related to both membrane expansion and membrane fusion, but the underlying molecular mechanisms are poorly understood. Here, we used two minimal reconstituted systems (enzymatic and chemical conjugation) to compare the ability of human ATG8 homologs (LC3, GABARAP, and GATE-16) to mediate membrane fusion. We found that both enzymatically and chemically lipidated forms of GATE-16 and GABARAP proteins promote extensive membrane tethering and fusion, whereas lipidated LC3 does so to a much lesser extent. Moreover, we characterize the GATE-16/GABARAP-mediated membrane fusion as a phenomenon of full membrane fusion, independently demonstrating vesicle aggregation, intervesicular lipid mixing, and intervesicular mixing of aqueous content, in the absence of vesicular content leakage. Multiple fusion events give rise to large vesicles, as seen by cryo-electron microscopy observations. We also show that both vesicle diameter and selected curvature-inducing lipids (cardiolipin, diacylglycerol, and lyso-phosphatidylcholine) can modulate the fusion process, smaller vesicle diameters and negative intrinsic curvature lipids (cardiolipin, diacylglycerol) facilitating fusion. These results strongly support the hypothesis of a highly bent structural fusion intermediate (stalk) during AP biogenesis and add to the growing body of evidence that identifies lipids as important regulators of autophagy. PMID:26789764

  14. Fish oil supplementation alters levels of lipid mediators of inflammation in microenvironment of acute human wounds

    PubMed Central

    McDaniel, Jodi C.; Massey, Karen; Nicolaou, Anna

    2013-01-01

    Chronic wounds often result from prolonged inflammation involving excessive polymorphonuclear leukocyte activity. Studies show that the ω-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) found in fish oils generate bioactive lipid mediators that reduce inflammation and polymorphonuclear leukocyte recruitment in numerous inflammatory disease models. This study’s purpose was to test the hypotheses that boosting plasma levels of EPA and DHA with oral supplementation would alter lipid mediator levels in acute wound microenvironments and reduce polymorphonuclear leukocyte levels. Eighteen individuals were randomized to 28 days of either EPA + DHA supplementation (Active Group) or placebo. After 28 days, the Active Group had significantly higher plasma levels of EPA (p < 0.001) and DHA (p < 0.001) than the Placebo Group and significantly lower wound fluid levels of two 15-lipoxygenase products of ω-6 polyunsaturated fatty acids (9-hydroxyoctadecadienoic acid [p=0.033] and 15-hydroxyeicosatrienoic acid [p=0.006]), at 24 hours postwounding. The Active Group also had lower mean levels of myeloperoxidase, a leukocyte marker, at 12 hours and significantly more reepithelialization on Day 5 postwounding. We suggest that lipid mediator profiles can be manipulated by altering polyunsaturated fatty acid intake to create a wound microenvironment more conducive to healing. PMID:21362086

  15. Synthesis, saccharide-binding and anti-cancer cell proliferation properties of arylboronic acid derivatives of indoquinolines.

    PubMed

    Meng, Junxiu; Yu, Shaoqing; Wan, Shengbiao; Ren, Sumei; Jiang, Tao

    2011-11-01

    A facile synthesis of a series of saccharide-binding arylboronic acid derivatives of indoloquinoline was described. The key synthetic steps were polyphosphoric acid-mediated cyclization, chlorinative aromatization, and amidation. Mass spectrometry experiments revealed these synthetic arylboronic acid derivatives of indoquinolines could bind to biologically important carbohydrates (sialic acid, fucose, glucose, and galactose) by forming boronate di-esters in alkaline aqueous solution. Most of the arylboronic acid derivatives of indoquinolines inhibited human breast cancer cell (MDA-231) proliferation at a concentration of 5 μm, whereas the compound 17 exhibited highest percentages (76.74%) of the cancer cell proliferation inhibition.

  16. Oxidative stress is a mediator for increased lipid accumulation in a newly isolated Dunaliella salina strain.

    PubMed

    Yilancioglu, Kaan; Cokol, Murat; Pastirmaci, Inanc; Erman, Batu; Cetiner, Selim

    2014-01-01

    oxidative stress mediates lipid accumulation. Understanding such relationships may provide guidance for efficient production of algal biodiesels.

  17. Lipid-Mediated Regulation of Embedded Receptor Kinases via Parallel Allosteric Relays.

    PubMed

    Ghosh, Madhubrata; Wang, Loo Chien; Ramesh, Ranita; Morgan, Leslie K; Kenney, Linda J; Anand, Ganesh S

    2017-02-28

    Membrane-anchored receptors are essential cellular signaling elements for stimulus sensing, propagation, and transmission inside cells. However, the contributions of lipid interactions to the function and dynamics of embedded receptor kinases have not been described in detail. In this study, we used amide hydrogen/deuterium exchange mass spectrometry, a sensitive biophysical approach, to probe the dynamics of a membrane-embedded receptor kinase, EnvZ, together with functional assays to describe the role of lipids in receptor kinase function. Our results reveal that lipids play an important role in regulating receptor function through interactions with transmembrane segments, as well as through peripheral interactions with nonembedded domains. Specifically, the lipid membrane allosterically modulates the activity of the embedded kinase by altering the dynamics of a glycine-rich motif that is critical for phosphotransfer from ATP. This allostery in EnvZ is independent of membrane composition and involves direct interactions with transmembrane and periplasmic segments, as well as peripheral interactions with nonembedded domains of the protein. In the absence of the membrane-spanning regions, lipid allostery is propagated entirely through peripheral interactions. Whereas lipid allostery impacts the phosphotransferase function of the kinase, extracellular stimulus recognition is mediated via a four-helix bundle subdomain located in the cytoplasm, which functions as the osmosensing core through osmolality-dependent helical stabilization. Our findings emphasize the functional modularity in a membrane-embedded kinase, separated into membrane association, phosphotransferase function, and stimulus recognition. These components are integrated through long-range communication relays, with lipids playing an essential role in regulation.

  18. Comparative time-courses of copper-ion-mediated protein and lipid oxidation in low-density lipoprotein.

    PubMed

    Knott, Heather M; Baoutina, Anna; Davies, Michael J; Dean, Roger T

    2002-04-15

    Free radicals damage both lipids and proteins and evidence has accumulated for the presence of both oxidised lipids and proteins in aged tissue samples as well as those from a variety of pathologies including atherosclerosis, diabetes, and Parkinson's disease. Oxidation of the protein and lipid moieties of low-density lipoprotein is of particular interest due to its potential role in the unregulated uptake of lipids and cholesterol by macrophages; this may contribute to the initial stage of foam cell formation in atherosclerosis. In the study reported here, we examined the comparative time-courses of lipid and protein oxidation during copper-ion-mediated oxidation of low-density lipoprotein. We show that there is an early, lipid-mediated loss of 40-50% of the Trp residues of the apoB100 protein. There is no comparable loss over an identical period during the copper-ion-mediated oxidation of lipid-free BSA. Concomitant with Trp loss, the antioxidant alpha-tocopherol is consumed with subsequent extensive lipid peroxidation. Further changes to the protein, including the copper-ion-dependent 3.5-fold increase in 3,4-dihydroxyphenylalanine and the copper-ion-independent 3-5-fold increase in o-tyrosine, oxidation products of Tyr and Phe, respectively, only occur after maximal lipid peroxidation. Long incubation periods result in depletion of 3,4-dihydroxyphenylalanine, presumably reflecting further oxidative changes. Overall, copper-ion-mediated oxidation of LDL appears to proceed initially by lipid radical-dependent processes, even though some of the earliest detectable changes occur on the apoB100 protein. This is followed by extensive lipid peroxidation and subsequent additional oxidation of aromatic residues on apoB100, though it is not yet clear whether this late protein oxidation is lipid-dependent or occurs as a result of direct radical attack.

  19. Lipid droplet-mediated ER homeostasis regulates autophagy and cell survival during starvation.

    PubMed

    Velázquez, Ariadna P; Tatsuta, Takashi; Ghillebert, Ruben; Drescher, Ingmar; Graef, Martin

    2016-03-14

    Lipid droplets (LDs) are conserved organelles for intracellular neutral lipid storage. Recent studies suggest that LDs function as direct lipid sources for autophagy, a central catabolic process in homeostasis and stress response. Here, we demonstrate that LDs are dispensable as a membrane source for autophagy, but fulfill critical functions for endoplasmic reticulum (ER) homeostasis linked to autophagy regulation. In the absence of LDs, yeast cells display alterations in their phospholipid composition and fail to buffer de novo fatty acid (FA) synthesis causing chronic stress and morphologic changes in the ER. These defects compromise regulation of autophagy, including formation of multiple aberrant Atg8 puncta and drastically impaired autophagosome biogenesis, leading to severe defects in nutrient stress survival. Importantly, metabolically corrected phospholipid composition and improved FA resistance of LD-deficient cells cure autophagy and cell survival. Together, our findings provide novel insight into the complex interrelation between LD-mediated lipid homeostasis and the regulation of autophagy potentially relevant for neurodegenerative and metabolic diseases.

  20. Sphingosine-1-phosphate and other lipid mediators generated by mast cells as critical players in allergy and mast cell function.

    PubMed

    Kulinski, Joseph M; Muñoz-Cano, Rosa; Olivera, Ana

    2016-05-05

    Sphingosine-1-phosphate (S1P), platelet activating factor (PAF) and eicosanoids are bioactive lipid mediators abundantly produced by antigen-stimulated mast cells that exert their function mostly through specific cell surface receptors. Although it has long been recognized that some of these bioactive lipids are potent regulators of allergic diseases, their exact contributions to disease pathology have been obscured by the complexity of their mode of action and the regulation of their metabolism. Indeed, the effects of such lipids are usually mediated by multiple receptor subtypes that may differ in their signaling mechanisms and functions. In addition, their actions may be elicited by cell surface receptor-independent mechanisms. Furthermore, these lipids may be converted into metabolites that exhibit different functionalities, adding another layer of complexity to their overall biological responses. In some instances, a second wave of lipid mediator synthesis by both mast cell and non-mast cell sources may occur late during inflammation, bringing about additional roles in the altered environment. New evidence also suggests that bioactive lipids in the local environment can fine-tune mast cell maturation and phenotype, and thus their responsiveness. A better understanding of the subtleties of the spatiotemporal regulation of these lipid mediators, their receptors and functions may aid in the pursuit of pharmacological applications for allergy treatments.

  1. Free radical scavenging, DNA protection, and inhibition of lipid peroxidation mediated by uric acid.

    PubMed

    Stinefelt, Beth; Leonard, Stephen S; Blemings, Kenneth P; Shi, Xianglin; Klandorf, Hillar

    2005-01-01

    Uric acid (UA) has been proposed to be the dominant antioxidant in birds. The objective of this study was to investigate the quenching effect of varying concentrations of UA, including those found in avian plasma, on specific reactive oxygen species (ROS) and to determine the ability of UA to protect DNA and cellular membranes from ROS-mediated damage. Hydroxyl (OH) and superoxide (O2-) radicals were detected by electron spin resonance (ESR) and their presence was reduced following addition of UA (p <0.05) in a concentration-dependent manner. UA inhibited hydroxyl-mediated DNA damage, indicated by the presence of more precise, dense bands of lambda Hind III DNA after agarose gel electrophoresis and ethidium bromide staining (p <0.05). Lipid peroxidation of silica-exposed RAW 264.7 cell membranes was diminished (p <0.02) after addition of UA to the cell incubation mixture. These studies demonstrate that UA scavenges hydroxyl and superoxide radicals and protects against DNA damage and lipid peroxidation. These results indicate specific antioxidant protection that UA may afford birds against ROS-mediated damage.

  2. NCAM-140 Translocation into Lipid Rafts Mediates the Neuroprotective Effects of GDNF.

    PubMed

    Li, Li; Chen, Huizhen; Wang, Meng; Chen, Fangfang; Gao, Jin; Sun, Shen; Li, Yunqing; Gao, Dianshuai

    2016-03-22

    Glial cell line-derived neurotrophic factor (GDNF) is a potent neurotrophic factor for substantia nigra dopaminergic (DA) neuronal cells. Recent studies have demonstrated that neural cell adhesion molecule functions as a signal transduction receptor for GDNF. The purpose of this study is to reveal whether neural cell adhesion molecule (NCAM) mediates the protective effects of GDNF on DA neuronal cells and further explore the mechanisms involved. We utilized SH-SY5Y cell line to establish a model of 6-hydroxydopamine (6-OHDA)-injured DA neuronal cells. Lentiviral vectors were constructed to knockdown or overexpress NCAM-140, and a density gradient centrifugation method was employed to separate membrane lipid rafts. 3-(4,5-Dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), flow cytometric analysis, and western blotting were used to evaluate the protective effects of GDNF. The results showed that GDNF could protect 6-OHDA-injured SH-SY5Y cells via improving cell viability and decreasing the cell death rate and cleaved caspase-3 expression. NCAM-140 knockdown decreased cell viability and increased the cell death rate and cleaved caspase-3 expression, while its overexpression had the opposite effects. Notably, the amount of NCAM-140 located in lipid rafts increased after GDNF treatment. Pretreatment with 2-bromopalmitate, a specific inhibitor of protein palmitoylation, suppressed NCAM-140 translocation to lipid rafts and reduced the NCAM-mediated protective effects of GDNF on injured DA neuronal cells. Our results suggest that GDNF have the protective effects on injured DA cells by influencing NCAM-140 translocation into lipid rafts.

  3. Cell type-specific modulation of lipid mediator's formation in murine adipose tissue by omega-3 fatty acids.

    PubMed

    Kuda, Ondrej; Rombaldova, Martina; Janovska, Petra; Flachs, Pavel; Kopecky, Jan

    2016-01-15

    Mutual interactions between adipocytes and immune cells in white adipose tissue (WAT) are involved in modulation of lipid metabolism in the tissue and also in response to omega-3 polyunsaturated fatty acids (PUFA), which counteract adverse effects of obesity. This complex interplay depends in part on in situ formed anti- as well as pro-inflammatory lipid mediators, but cell types engaged in the synthesis of the specific mediators need to be better characterized. We used tissue fractionation and metabolipidomic analysis to identify cells producing lipid mediators in epididymal WAT of mice fed for 5 weeks obesogenic high-fat diet (lipid content 35% wt/wt), which was supplemented or not by omega-3 PUFA (4.3 mg eicosapentaenoic acid and 14.7 mg docosahexaenoic acid per g of diet). Our results demonstrate selective increase in levels of anti-inflammatory lipid mediators in WAT in response to omega-3, reflecting either their association with adipocytes (endocannabinoid-related N-docosahexaenoylethanolamine) or with stromal vascular cells (pro-resolving lipid mediator protectin D1). In parallel, tissue levels of obesity-associated pro-inflammatory endocannabinoids were suppressed. Moreover, we show that adipose tissue macrophages (ATMs), which could be isolated using magnetic force from the stromal vascular fraction, are not the major producers of protectin D1 and that omega-3 PUFA lowered lipid load in ATMs while promoting their less-inflammatory phenotype. Taken together, these results further document specific roles of various cell types in WAT in control of WAT inflammation and metabolism and they suggest that also other cells but ATMs are engaged in production of pro-resolving lipid mediators in response to omega-3 PUFA.

  4. Human serum activates CIDEB-mediated lipid droplet enlargement in hepatoma cells

    SciTech Connect

    Singaravelu, Ragunath; Lyn, Rodney K.; Srinivasan, Prashanth; Delcorde, Julie; Steenbergen, Rineke H.; Tyrrell, D. Lorne; Pezacki, John P.

    2013-11-15

    Highlights: •Human serum induced differentiation of hepatoma cells increases cellular lipid droplet (LD) size. •The observed increase in LD size correlates with increased PGC-1α and CIDEB expression. •Induction of CIDEB expression correlates with rescue of VLDL secretion and loss of ADRP. •siRNA knockdown of CIDEB impairs the human serum mediated increase in LD size. •This system represents a cost-efficient model to study CIDEB’s role in lipid biology. -- Abstract: Human hepatocytes constitutively express the lipid droplet (LD) associated protein cell death-inducing DFFA-like effector B (CIDEB). CIDEB mediates LD fusion, as well as very-low-density lipoprotein (VLDL) maturation. However, there are limited cell culture models readily available to study CIDEB’s role in these biological processes, as hepatoma cell lines express negligible levels of CIDEB. Recent work has highlighted the ability of human serum to differentiate hepatoma cells. Herein, we demonstrate that culturing Huh7.5 cells in media supplemented with human serum activates CIDEB expression. This activation occurs through the induced expression of PGC-1α, a positive transcriptional regulator of CIDEB. Coherent anti-Stokes Raman scattering (CARS) microscopy revealed a correlation between CIDEB levels and LD size in human serum treated Huh7.5 cells. Human serum treatment also resulted in a rapid decrease in the levels of adipose differentiation-related protein (ADRP). Furthermore, individual overexpression of CIDEB was sufficient to down-regulate ADRP protein levels. siRNA knockdown of CIDEB revealed that the human serum mediated increase in LD size was CIDEB-dependent. Overall, our work highlights CIDEB’s role in LD fusion, and presents a new model system to study the PGC-1α/CIDEB pathway’s role in LD dynamics and the VLDL pathway.

  5. Specialized proresolving lipid mediators in patients with coronary artery disease and their potential for clot remodeling.

    PubMed

    Elajami, Tarec K; Colas, Romain A; Dalli, Jesmond; Chiang, Nan; Serhan, Charles N; Welty, Francine K

    2016-08-01

    Inflammation in arterial walls leads to coronary artery disease (CAD). Because specialized proresolving lipid mediators (SPMs; lipoxins, resolvins, and protectins) stimulate resolution of inflammation in animal models, we tested whether n-3 fatty acids impact SPM profiles in patients with CAD and promote clot remodeling. Six patients with stable CAD were randomly assigned to either treatment with daily 3.36 g Lovaza for 1 yr or without. Targeted lipid mediator-metabololipidomics showed that both groups had absence of resolvin D1 (RvD1), RvD2, RvD3, RvD5 and resolvin E1-all of which are present in healthy patients. Those not taking Lovaza had an absence of aspirin-triggered resolvin D3 (AT-RvD3) and aspirin-triggered lipoxin B4 (AT-LXB4). Lovaza treatment restored AT-RvD3 and AT-LXB4 and gave levels of RvD6 and aspirin-triggered protectin D1 (AT-PD1) twice as high (resolvin E2 ∼5 fold) as well as lower prostaglandins. Principal component analysis indicated positive relationships for patients with CAD who were receiving Lovaza with increased AT-RvD3, RvD6, AT-PD1, and AT-LXB4 SPMs identified in Lovaza-treated patients with CAD enhanced ∼50% at 1 nM macrophage uptake of blood clots. These results indicate that patients with CAD have lower levels and/or absence of specific SPMs that were restored with Lovaza; these SPMs promote macrophage phagocytosis of blood clots. Together, they suggest that low vascular SPMs may enable progression of chronic vascular inflammation predisposing to coronary atherosclerosis and to thrombosis.-Elajami, T. K., Colas, R. A., Dalli, J., Chiang, N., Serhan, C. N., Welty, F. K. Specialized proresolving lipid mediators in patients with coronary artery disease and their potential for clot remodeling.

  6. Stereoselective synthesis of protectin D1: A potent anti-inflammatory and proresolving lipid mediator

    PubMed Central

    Aursnes, M.; Tungen, J. E.; Vik, A.; Dalli, J.; Hansen, T. V.

    2014-01-01

    A convergent stereoselective synthesis of the potent anti-inflammatory, proresolving and neuroprotective lipid mediator protectin D1 (2) has been achieved in 15% yield over eight steps. The key features were a stereocontrolled Evans-aldol reaction with Nagao’s chiral auxiliary and a highly selective Lindlar reduction of internal alkyne 23, allowing the sensitive conjugated E,E,Z-triene to be introduced late in the preparation of 2. The UV and LC/MS-MS data of synthetic protectin D1 (2) matched those obtained from endogenously produced material PMID:24253202

  7. Leukotriene inflammatory mediators meet their match.

    PubMed

    Funk, Colin D

    2011-01-19

    Leukotrienes are arachidonic acid-derived lipid mediators of inflammation. The initial catalytic step in the formation of leukotrienes is catalyzed by 5-lipoxygenase (5-LOX) in conjunction with its activating partner protein FLAP. The long-awaited crystal structure of 5-LOX--reported in a recent issue of Science--should lead to novel, purpose-designed inhibitors for the treatment of asthma and for probing leukotriene involvement in cardiovascular disease and cancer.

  8. The Resolution Code of Acute Inflammation: Novel Pro-Resolving Lipid Mediators in Resolution

    PubMed Central

    Serhan, Charles N.; Chiang, Nan; Dalli, Jesmond

    2015-01-01

    Studies into the mechanisms in resolution of self-limited inflammation and acute reperfusion injury have uncovered a new genus of pro-resolving lipid mediators coined specialized pro-resolving mediators (SPM) including lipoxins, resolvins, protectins and maresins that are each temporally produced by resolving-exudates with distinct actions for return to homeostasis. SPM evoke potent anti-inflammatory and novel pro-resolving mechanisms as well as enhance microbial clearance. While born in inflammation-resolution, SPM are conserved structures with functions discovered in microbial defense, pain, organ protection and tissue regeneration, wound healing, cancer, reproduction, and neurobiology-cognition. This review covers these SPM mechanisms and other new omega-3 PUFA pathways that open their path for functions in resolution physiology. PMID:25857211

  9. Fatty acid-derived diisocyanate and biobased polyurethane produced from vegetable oil: synthesis, polymerization, and characterization.

    PubMed

    Hojabri, Leila; Kong, Xiaohua; Narine, Suresh S

    2009-04-13

    A new linear saturated terminal diisocyanate was synthesized from oleic acid via Curtius rearrangement, and its chemical structure was identified by FTIR, (1)H and (13)C NMR, and MS. The feasibility of utilizing this new diisocyanate for the production of polyurethanes (PUs) was demonstrated by reacting it with commercial petroleum-derived polyols and canola oil-derived polyols, respectively. The physical properties of the PUs prepared from fatty acid-derived diisocyanate were compared to those prepared from the same polyols with a similar but petroleum-derived commercially available diisocyanate: 1,6-hexamethylene diisocyanate. It was found that the fatty acid-derived diisocyanate was capable of producing PUs with comparable properties within acceptable tolerances. This work is the first that establishes the production of linear saturated terminal diisocyanate derived from fatty acids and corresponding PUs mostly from lipid feedstock.

  10. Motor-mediated Cortical versus Astral Microtubule Organization in Lipid-monolayered Droplets

    PubMed Central

    Baumann, Hella; Surrey, Thomas

    2014-01-01

    The correct spatial organization of microtubules is of crucial importance for determining the internal architecture of eukaryotic cells. Microtubules are arranged in space by a multitude of biochemical activities and by spatial constraints imposed by the cell boundary. The principles underlying the establishment of distinct intracellular architectures are only poorly understood. Here, we studied the effect of spatial confinement on the self-organization of purified motors and microtubules that are encapsulated in lipid-monolayered droplets in oil, varying in diameter from 5–100 μm, which covers the size range of typical cell bodies. We found that droplet size alone had a major organizing influence. The presence of a microtubule-crosslinking motor protein decreased the number of accessible types of microtubule organizations. Depending on the degree of spatial confinement, the presence of the motor caused either the formation of a cortical array of bent microtubule bundles or the generation of single microtubule asters in the droplets. These are two of the most prominent forms of microtubule arrangements in plant and metazoan cells. Our results provide insights into the combined organizing influence of spatial constraints and cross-linking motor activities determining distinct microtubule architectures in a minimal biomimetic system. In the future, this simple lipid-monolayered droplet system characterized here can be expanded readily to include further biochemical activities or used as the starting point for the investigation of motor-mediated microtubule organization inside liposomes surrounded by a deformable lipid bilayer. PMID:24966327

  11. Theoretical analysis of hydrophobic matching and membrane-mediated interactions in lipid bilayers containing gramicidin.

    PubMed Central

    Harroun, T A; Heller, W T; Weiss, T M; Yang, L; Huang, H W

    1999-01-01

    We present a quantitative analysis of the effects of hydrophobic matching and membrane-mediated protein-protein interactions exhibited by gramicidin embedded in dimyristoylphosphatidylcholine (DMPC) and dilauroylphosphatidylcholine (DLPC) bilayers (Harroun et al., 1999. Biophys. J. 76:937-945). Incorporating gramicidin, at 1:10 peptide/lipid molar ratio, decreases the phosphate-to-phosphate (PtP) peak separation in the DMPC bilayer from 35.3 A without gramicidin to 32.7 A. In contrast, the same molar ratio of gramicidin in DLPC increases the PtP from 30.8 A to 32.1 A. Concurrently, x-ray in-plane scattering showed that the most probable nearest-neighbor separation between gramicidin channels was 26.8 A in DLPC, but reduced to 23.3 A in DMPC. In this paper we review the idea of hydrophobic matching in which the lipid bilayer deforms to match the hydrophobic surface of the embedded proteins. We use a simple elasticity theory, including thickness compression, tension, and splay terms to describe the membrane deformation. The energy of membrane deformation is compared with the energy cost of hydrophobic mismatch. We discuss the boundary conditions between a gramicidin channel and the lipid bilayer. We used a numerical method to solve the problem of membrane deformation profile in the presence of a high density of gramicidin channels and ran computer simulations of 81 gramicidin channels to find the equilibrium distributions of the channels in the plane of the bilayer. The simulations contain four parameters: bilayer thickness compressibility 1/B, bilayer bending rigidity Kc, the channel-bilayer mismatch Do, and the slope of the interface at the lipid-protein boundary s. B, Kc, and Do were experimentally measured; the only free parameter is s. The value of s is determined by the requirement that the theory produces the experimental values of bilayer thinning by gramicidin and the shift in the peak position of the in-plane scattering due to membrane-mediated channel

  12. Lipid-Mediated Targeting with Membrane Wrapped Nanoparticles in the Presence of Corona Formation

    PubMed Central

    Xu, Fangda; Reiser, Michael; Yu, Xinwei; Gummuluru, Suryaram; Wetzler, Lee; Reinhard, Björn M.

    2016-01-01

    Membrane wrapped nanoparticles represent a versatile platform for utilizing specific lipid-receptor interactions, such as siallyllactose-mediated binding of the ganglioside GM3 to Siglec1 (CD169), for targeting purposes. The membrane wrap around the nanoparticles does not only serve as a matrix to incorporate GM3 as targeting moiety for antigen presenting cells but also offers unique opportunities for constructing a biomimetic surface from lipids with potentially protein repellent properties. We characterize non-specific protein adsorption (corona formation) to membrane wrapped nanoparticles with core diameters of approx. 35 nm and 80 nm and its effect on the GM3-mediated targeting efficacy as function of surface charge through combined in vitro and in vivo studies. The stability and fate of the membrane wrap around the nanoparticles in a simulated biological fluid and after uptake in CD169 expressing antigen presenting cells is experimentally tested. Finally, we demonstrate in hock immunization studies in mice that GM3 decorated membrane wrapped nanoparticles achieve a selective enrichment in the peripheral regions of popliteal lymph nodes that contain high concentrations of CD169 expressing antigen presenting cells. PMID:26720275

  13. Inflammatory lipid mediator generation elicited by viable hemolysin- forming Escherichia coli in lung vasculature

    PubMed Central

    1990-01-01

    Escherichia coli hemolysin, a transmembrane pore-forming exotoxin, is considered an important virulence factor for E. coli-related extraintestinal infections and sepsis. The possible significance of hemolysin liberation for induction of inflammatory lipid mediators was investigated in isolated rabbit lungs infused with viable bacteria (concentration range, 10(4)-10(7)/ml). Hemolysin-secreting E. coli (E. coli-Hly+), but not an E. coli strain that releases an inactive form of the exotoxin, induced marked lung leukotriene (LT) generation with predominance of cysteinyl LTs. Eicosanoid synthesis was not inhibited in the presence of plasma with toxin-neutralizing capacity. Pre- application of 2 x 10(8) human granulocytes, which sequestered in the lung microvasculature, caused a severalfold increase in leukotriene generation in response to E. coli-Hly+ challenge both in the absence and presence of plasma. Data are presented indicating neutrophil- endothelial cell cooperation in arachidonic acid lipoxygenase metabolism as an underlying mechanism. We conclude that liberation of hemolysin from viable E. coli induces marked lipid mediator generation in lung vasculature, which is potentiated in the presence of neutrophil sequestration and may contribute to microcirculatory disturbances during the course of severe infections. PMID:2120384

  14. Surface Lipids as Multifunctional Mediators of Skin Responses to Environmental Stimuli

    PubMed Central

    De Luca, Chiara; Valacchi, Giuseppe

    2010-01-01

    Skin surface lipid (SSL) film is a mixture of sebum and keratinocyte membrane lipids, protecting skin from environment. Its composition is unique for the high percentage of long chain fatty acids, and of the polyterpenoid squalene, absent in other human tissues, and in non-human Primates sebum. Here, the still incomplete body of information on SSL as mediators of external chemical, physical, and microbial signals and stressors is revised, focusing on the central event of the continuous oxidative modification induced by the metabolic activity of residential and pathological microbial flora, natural or iatrogenic UV irradiation, exposure to chemicals and cosmetics. Once alpha-tocopherol and ubiquinol-10 antioxidant defences of SSL are overcome, oxidation of squalene and cholesterol gives rise to reactive by-products penetrating deeper into skin layers, to mediate local defensive inflammatory, photo-protective, immune reactions or, at higher concentrations, inducing local but also systemic immune depression, ultimately implicating skin cancerogenesis. Qualitative modifications of SSL represent a pathogenetic sign of diagnostic value in dermatological disorders involving altered sebum production, like pytiriasis versicolor, acne, atopic or seborrheic dermatitis, as well as photo-aging. Achievements of nutriceutical interventions aimed at restoring normal SSL composition and homeostasis are discussed, as feasible therapeutic goals and major means of photo-protection. PMID:20981292

  15. Surface lipids as multifunctional mediators of skin responses to environmental stimuli.

    PubMed

    De Luca, Chiara; Valacchi, Giuseppe

    2010-01-01

    Skin surface lipid (SSL) film is a mixture of sebum and keratinocyte membrane lipids, protecting skin from environment. Its composition is unique for the high percentage of long chain fatty acids, and of the polyterpenoid squalene, absent in other human tissues, and in non-human Primates sebum. Here, the still incomplete body of information on SSL as mediators of external chemical, physical, and microbial signals and stressors is revised, focusing on the central event of the continuous oxidative modification induced by the metabolic activity of residential and pathological microbial flora, natural or iatrogenic UV irradiation, exposure to chemicals and cosmetics. Once alpha-tocopherol and ubiquinol-10 antioxidant defences of SSL are overcome, oxidation of squalene and cholesterol gives rise to reactive by-products penetrating deeper into skin layers, to mediate local defensive inflammatory, photo-protective, immune reactions or, at higher concentrations, inducing local but also systemic immune depression, ultimately implicating skin cancerogenesis. Qualitative modifications of SSL represent a pathogenetic sign of diagnostic value in dermatological disorders involving altered sebum production, like pytiriasis versicolor, acne, atopic or seborrheic dermatitis, as well as photo-aging. Achievements of nutriceutical interventions aimed at restoring normal SSL composition and homeostasis are discussed, as feasible therapeutic goals and major means of photo-protection.

  16. Ca(2+)-mediated anionic lipid-plasmid DNA lipoplexes. Electrochemical, structural, and biochemical studies.

    PubMed

    Barrán-Berdón, Ana L; Yélamos, Belén; Malfois, Marc; Aicart, Emilio; Junquera, Elena

    2014-10-07

    . This fact would be indicating that, nowadays, lipofection via anionic lipids and divalent cations as mediators still needs to enhance transfection levels in order to be considered as a real and plausible alternative to lipofection through improved CLs-based lipoplexes.

  17. Inhibition of lipase and inflammatory mediators by Chlorella lipid extracts for antiacne treatment

    PubMed Central

    Sibi, G.

    2015-01-01

    pathogen could be reduced by the inhibiting the production of ROS and inflammatory mediators TNF-α and exposes new frontiers on the antiacne activities of Chlorella lipid extracts. PMID:25709963

  18. High lipid order of Arabidopsis cell-plate membranes mediated by sterol and DYNAMIN-RELATED PROTEIN1A function.

    PubMed

    Frescatada-Rosa, Márcia; Stanislas, Thomas; Backues, Steven K; Reichardt, Ilka; Men, Shuzhen; Boutté, Yohann; Jürgens, Gerd; Moritz, Thomas; Bednarek, Sebastian Y; Grebe, Markus

    2014-12-01

    Membranes of eukaryotic cells contain high lipid-order sterol-rich domains that are thought to mediate temporal and spatial organization of cellular processes. Sterols are crucial for execution of cytokinesis, the last stage of cell division, in diverse eukaryotes. The cell plate of higher-plant cells is the membrane structure that separates daughter cells during somatic cytokinesis. Cell-plate formation in Arabidopsis relies on sterol- and DYNAMIN-RELATED PROTEIN1A (DRP1A)-dependent endocytosis. However, functional relationships between lipid membrane order or lipid packing and endocytic machinery components during eukaryotic cytokinesis have not been elucidated. Using ratiometric live imaging of lipid order-sensitive fluorescent probes, we show that the cell plate of Arabidopsis thaliana represents a dynamic, high lipid-order membrane domain. The cell-plate lipid order was found to be sensitive to pharmacological and genetic alterations of sterol composition. Sterols co-localize with DRP1A at the cell plate, and DRP1A accumulates in detergent-resistant membrane fractions. Modifications of sterol concentration or composition reduce cell-plate membrane order and affect DRP1A localization. Strikingly, DRP1A function itself is essential for high lipid order at the cell plate. Our findings provide evidence that the cell plate represents a high lipid-order domain, and pave the way to explore potential feedback between lipid order and function of dynamin-related proteins during cytokinesis.

  19. Immunopathologic effects of scorpion venom on hepato-renal tissues: Involvement of lipid derived inflammatory mediators.

    PubMed

    Lamraoui, Amal; Adi-Bessalem, Sonia; Laraba-Djebari, Fatima

    2015-10-01

    Scorpion venoms are known to cause different inflammatory disorders through complex mechanisms in various tissues. In the study here, the involvement of phospholipase A2 (PLA2) and cyclo-oxygenase (COX)-derived metabolites in hepatic and renal inflammation responses were examined. Mice were envenomed with Androctonus australis hector scorpion venom in the absence or presence of inhibitors that can interfere with lipid inflammatory mediator synthesis, i.e., dexamethasone (PLA2 inhibitor), indomethacin (non-selective COX-1/COX-2 inhibitor), or celecoxib (selective COX-2 inhibitor). The inflammatory response was assessed by evaluating vascular permeability changes, inflammatory cell infiltration, oxidative/nitrosative stress marker levels, and by histologic and functional analyses of the liver and kidney. Results revealed that the venom alone induced an inflammatory response in this tissues marked by increased microvascular permeability and inflammatory cell infiltration, increases in levels of nitric oxide and lipid peroxidation, and decreases in antioxidant defense. Moreover, significant alterations in the histological architecture of these organs were associated with increased serum levels of some metabolic enzymes, as well as urea and uric acid. Pre-treatment of mice with dexamethasone led to significant decreases of the inflammatory disorders in the hepatic parenchyma; celecoxib pre-treatment seemed to be more effective against renal inflammation. Indomethacin pre-treatment only slightly reduced the inflammatory disorders in the tissues. These results suggest that the induced inflammation response in liver was mediated mainly by PLA2 activation, while the renal inflammatory process was mediated by prostaglandin formation by COX-2. These findings provide additional insight toward the understanding of activated pathways and related mechanisms involved in scorpion envenoming syndrome.

  20. Dysregulation of the Low-Density Lipoprotein Receptor Pathway Is Involved in Lipid Disorder-Mediated Organ Injury

    PubMed Central

    Zhang, Yang; Ma, Kun Ling; Ruan, Xiong Zhong; Liu, Bi Cheng

    2016-01-01

    The low-density lipoprotein receptor (LDLR) pathway is a negative feedback system that plays important roles in the regulation of plasma and intracellular cholesterol homeostasis. To maintain a cholesterol homeostasis, LDLR expression is tightly regulated by sterol regulatory element-binding protein-2 (SREBP-2) and SREBP cleavage-activating protein (SCAP) in transcriptional level and by proprotein convertase subtilisin/kexin type 9 (PCSK9) in posttranscriptional level. The dysregulation of LDLR expression results in abnormal lipid accumulation in cells and tissues, such as vascular smooth muscle cells, hepatic cells, renal mesangial cells, renal tubular cells and podocytes. It has been demonstrated that inflammation, renin-angiotensin system (RAS) activation, and hyperglycemia induce the disruption of LDLR pathway, which might contribute to lipid disorder-mediated organ injury (atherosclerosis, non-alcoholic fatty liver disease, kidney fibrosis, etc). The mammalian target of rapamycin (mTOR) pathway is a critical mediator in the disruption of LDLR pathway caused by pathogenic factors. The mTOR complex1 activation upregulates LDLR expression at the transcriptional and posttranscriptional levels, consequently resulting in lipid deposition. This paper mainly reviews the mechanisms for the dysregulation of LDLR pathway and its roles in lipid disorder-mediated organ injury under various pathogenic conditions. Understanding these mechanisms leading to the abnormality of LDLR expression contributes to find potential new drug targets in lipid disorder-mediated diseases. PMID:27019638

  1. Covalent attachment of lipid vesicles to a fluid supported bilayer allows observation of DNA-mediated vesicle interactions

    PubMed Central

    van Lengerich, Bettina; Rawle, Robert J.; Boxer, Steven G.

    2010-01-01

    Specific membrane interactions such as lipid vesicle docking and fusion can be mediated by synthetic DNA-lipid conjugates as a model for the protein-driven processes that are ubiquitous in biological systems. Here we present a method of tethering vesicles to a supported lipid bilayer that allows simultaneous deposition of cognate vesicle partners displaying complementary DNA, resulting in well-mixed populations of tethered vesicles that are laterally mobile. Vesicles are covalently attached to a supporting lipid bilayer using a DNA-templated click reaction; then DNA-mediated interactions between tethered vesicles are triggered by spiking the salt concentration. These interactions, such as docking and fusion, can then be observed for individual vesicles as they collide on the surface. The architecture of this new system also permits control over the number of lipid anchors that tether the vesicle to the supporting bilayer. The diffusion coefficient of tethered vesicles anchored by two lipids is approximately 1.6-fold slower than that of vesicles anchored only with a single lipid, consistent with a simple physical model. PMID:20180548

  2. Potential of specialized pro-resolving lipid mediators against rheumatic diseases.

    PubMed

    Murakami, Kosaku

    2016-01-01

      While arachidonic acid (AA), which is classified into n-6 polyunsaturated fatty acid (PUFA), has been mainly recognized as a substrate of pro-inflammatory mediators, eicosapentaenoic acid or docosahexaenoic acid, which are classified into n-3 PUFA, is currently identified as substrates of mediators inducing resolution of inflammation, namely pro-resolving mediators (SPM). As with any other pathological conditions, it is gradually elucidated that SPMs contributes a certain effect on joint inflammation. In osteoarthritis (OA), Lipid fractions extracted from adipocytes, especially in infrapatellar fat pad rather than subcutaneous tissue induce T cell skewing for producing IFN-γ or decrease the production of IL-12p40 from macrophages. In synovial tissues form OA, there are some of known receptors for SPM. In the synovial fluid from rheumatoid arthritis (RA), it could be identified and quantified a certain kind of SPMs such as maresin 1, lipoxin A4 and resolvin D5. In murine models of arthritis, some of SPMs are found to have some functions to reduce tissue damage. Correctively, SPMs might have some potential to a novel therapeutic target for arthritis or any other rheumatic diseases.

  3. Experimental evidence for hydrophobic matching and membrane-mediated interactions in lipid bilayers containing gramicidin.

    PubMed Central

    Harroun, T A; Heller, W T; Weiss, T M; Yang, L; Huang, H W

    1999-01-01

    Hydrophobic matching, in which transmembrane proteins cause the surrounding lipid bilayer to adjust its hydrocarbon thickness to match the length of the hydrophobic surface of the protein, is a commonly accepted idea in membrane biophysics. To test this idea, gramicidin (gD) was embedded in 1, 2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) and 1, 2-myristoyl-sn-glycero-3-phosphocholine (DMPC) bilayers at the peptide/lipid molar ratio of 1:10. Circular dichroism (CD) was measured to ensure that the gramicidin was in the beta6.3 helix form. The bilayer thickness (the phosphate-to-phosphate distance, or PtP) was measured by x-ray lamellar diffraction. In the Lalpha phase near full hydration, PtP is 30.8 A for pure DLPC, 32.1 A for the DLPC/gD mixture, 35.3 A for pure DMPC, and 32.7 A for the DMPC/gD mixture. Gramicidin apparently stretches DLPC and thins DMPC toward a common thickness as expected by hydrophobic matching. Concurrently, gramicidin-gramicidin correlations were measured by x-ray in-plane scattering. In the fluid phase, the gramicidin-gramicidin nearest-neighbor separation is 26.8 A in DLPC, but shortens to 23.3 A in DMPC. These experiments confirm the conjecture that when proteins are embedded in a membrane, hydrophobic matching creates a strain field in the lipid bilayer that in turn gives rise to a membrane-mediated attractive potential between proteins. PMID:9929495

  4. HDL surface lipids mediate CETP binding as revealed by electron microscopy and molecular dynamics simulation

    SciTech Connect

    Zhang, Meng; Charles, River; Tong, Huimin; Zhang, Lei; Patel, Mili; Wang, Francis; Rames, Matthew J.; Ren, Amy; Rye, Kerry-Anne; Qiu, Xiayang; Johns, Douglas G.; Charles, M. Arthur; Ren, Gang

    2015-03-04

    Cholesteryl ester transfer protein (CETP) mediates the transfer of cholesterol esters (CE) from atheroprotective high-density lipoproteins (HDL) to atherogenic low-density lipoproteins (LDL). CETP inhibition has been regarded as a promising strategy for increasing HDL levels and subsequently reducing the risk of cardiovascular diseases (CVD). Although the crystal structure of CETP is known, little is known regarding how CETP binds to HDL. Here, we investigated how various HDL-like particles interact with CETP by electron microscopy and molecular dynamics simulations. Results showed that CETP binds to HDL via hydrophobic interactions rather than protein-protein interactions. The HDL surface lipid curvature generates a hydrophobic environment, leading to CETP hydrophobic distal end interaction. This interaction is independent of other HDL components, such as apolipoproteins, cholesteryl esters and triglycerides. Thus, disrupting these hydrophobic interactions could be a new therapeutic strategy for attenuating the interaction of CETP with HDL.

  5. HDL surface lipids mediate CETP binding as revealed by electron microscopy and molecular dynamics simulation

    NASA Astrophysics Data System (ADS)

    Zhang, Meng; Charles, River; Tong, Huimin; Zhang, Lei; Patel, Mili; Wang, Francis; Rames, Matthew J.; Ren, Amy; Rye, Kerry-Anne; Qiu, Xiayang; Johns, Douglas G.; Charles, M. Arthur; Ren, Gang

    2015-03-01

    Cholesteryl ester transfer protein (CETP) mediates the transfer of cholesterol esters (CE) from atheroprotective high-density lipoproteins (HDL) to atherogenic low-density lipoproteins (LDL). CETP inhibition has been regarded as a promising strategy for increasing HDL levels and subsequently reducing the risk of cardiovascular diseases (CVD). Although the crystal structure of CETP is known, little is known regarding how CETP binds to HDL. Here, we investigated how various HDL-like particles interact with CETP by electron microscopy and molecular dynamics simulations. Results showed that CETP binds to HDL via hydrophobic interactions rather than protein-protein interactions. The HDL surface lipid curvature generates a hydrophobic environment, leading to CETP hydrophobic distal end interaction. This interaction is independent of other HDL components, such as apolipoproteins, cholesteryl esters and triglycerides. Thus, disrupting these hydrophobic interactions could be a new therapeutic strategy for attenuating the interaction of CETP with HDL.

  6. Forty five years with membrane phospholipids, phospholipases and lipid mediators: A historical perspective.

    PubMed

    Chap, Hugues

    2016-06-01

    Phospholipases play a key role in the metabolism of phospholipids and in cell signaling. They are also a very useful tool to explore phospholipid structure and metabolism as well as membrane organization. They are at the center of this review, covering a period starting in 1971 and focused on a number of subjects in which my colleagues and I have been involved. Those include determination of phospholipid asymmetry in the blood platelet membrane, biosynthesis of lysophosphatidic acid, biochemistry of platelet-activating factor, first attempts to define the role of phosphoinositides in cell signaling, and identification of novel digestive (phospho)lipases such as pancreatic lipase-related protein 2 (PLRP2) or phospholipase B. Besides recalling some of our contributions to those various fields, this review makes an appraisal of the impressive and often unexpected evolution of those various aspects of membrane phospholipids and lipid mediators. It is also the occasion to propose some new working hypotheses.

  7. HDL surface lipids mediate CETP binding as revealed by electron microscopy and molecular dynamics simulation

    DOE PAGES

    Zhang, Meng; Charles, River; Tong, Huimin; ...

    2015-03-04

    Cholesteryl ester transfer protein (CETP) mediates the transfer of cholesterol esters (CE) from atheroprotective high-density lipoproteins (HDL) to atherogenic low-density lipoproteins (LDL). CETP inhibition has been regarded as a promising strategy for increasing HDL levels and subsequently reducing the risk of cardiovascular diseases (CVD). Although the crystal structure of CETP is known, little is known regarding how CETP binds to HDL. Here, we investigated how various HDL-like particles interact with CETP by electron microscopy and molecular dynamics simulations. Results showed that CETP binds to HDL via hydrophobic interactions rather than protein-protein interactions. The HDL surface lipid curvature generates a hydrophobicmore » environment, leading to CETP hydrophobic distal end interaction. This interaction is independent of other HDL components, such as apolipoproteins, cholesteryl esters and triglycerides. Thus, disrupting these hydrophobic interactions could be a new therapeutic strategy for attenuating the interaction of CETP with HDL.« less

  8. Estradiol mediates vasculoprotection via ERRα-dependent regulation of lipid and ROS metabolism in the endothelium.

    PubMed

    Li, Huawen; Liu, Zhaoyu; Gou, Yulan; Yu, Haibing; Siminelakis, Stavros; Wang, Shixuan; Kong, Danli; Zhou, Yikai; Liu, Zhengxiang; Ding, Yuanling; Yao, Dachun

    2015-10-01

    The estrogen-mediated vasculoprotective effect has been widely reported in many animal studies, although the clinical trials are controversial and the detailed mechanisms remain unclear. In this study, we focused on the molecular mechanism and consequence of 17β-estradiol (E2)-induced ERRα (estrogen-related receptor alpha) expression in endothelium and its potential beneficial effects on vascular function. The human aorta endothelial cells were used to identify the detailed molecular mechanism and consequences for E2-induced ERRα expression through estrogen receptors (ER), where ERα responses E2-induced ERRα activation, and ERβ responses basal ERRα expression. E2-induced ERRα expression increases fatty acid uptake/oxidation with increased mitochondrial replication, ATP generation and attenuated reactive oxygen species (ROS) formation. We have obtained further in vivo proof from high-fat diet mice that the lentivirus-carried endothelium-specific delivery of ERRα expression on the vascular wall normalizes E2 deficiency-induced increased plasma lipids with ameliorated vascular damage. ERRα knockdown worsens the problem, and the E2 could only partly restore this effect. This is the first time we report the detailed mechanism with direct evidence that E2-induced ERRα expression modulates the fatty acid metabolism and reduces the circulating lipids through endothelium. We conclude that E2-induced ERRα expression in endothelium plays an important role for the E2-induced vasculoprotective effect.

  9. Cis and Trans Cooperativity of E-Cadherin Mediates Adhesion in Biomimetic Lipid Droplets

    PubMed Central

    Pontani, Lea-Laetitia; Jorjadze, Ivane; Brujic, Jasna

    2016-01-01

    The regulation of cell-cell adhesion is important in cell motility, tissue growth, and for the mechanical integrity of tissues. Although the role of active cytoskeleton dynamics in regulating cadherin interactions is crucial in vivo, here we present a biomimetic emulsion system to characterize the passive E-cadherin-mediated adhesion between droplets. The visualization of a three-dimensional assembly of lipid droplets, functionalized with extracellular E-cadherin domains, reveals a hierarchy of homophilic interactions. First, the high interfacial tension of droplets facilitates trans cadherin-cadherin adhesion, which is strong enough to stabilize looser than random close packing configurations. Second, fluorescence enhancement shows that adding clustering agents, such as calcium or chelating ligands, favor the lateral cis adhesion of the already bound cadherin pairs over the clustering of monomer cadherin on the surface. Finally, above a threshold cadherin and calcium concentration, the cis and trans protein interactions become strong enough to trigger and promote droplet fusion. While E-cadherin is not known to participate in cellular fusion, this mechanism is general because replacing calcium with cholesterol to cluster the cadherin-carrying lipids also promotes fusion. These results suggest that passive clustering, via calcium-induced dimerization or membrane ordering, may contribute to the reinforcement of cell-cell contacts. Alternatively, a molecular switch for fusion offers a route to mixing droplet contents and controlling their size in situ. PMID:26789762

  10. Mitochondrial Outer Membrane Proteins Assist Bid in Bax-mediated Lipidic Pore Formation

    PubMed Central

    Schafer, Blanca; Quispe, Joel; Choudhary, Vineet; Chipuk, Jerry E.; Ajero, Teddy G.; Du, Han; Schneiter, Roger

    2009-01-01

    Mitochondrial outer membrane permeabilization (MOMP) is a critical step in apoptosis and is regulated by Bcl-2 family proteins. In vitro systems using cardiolipin-containing liposomes have demonstrated the key features of MOMP induced by Bax and cleaved Bid; however, the nature of the “pores” and how they are formed remain obscure. We found that mitochondrial outer membranes contained very little cardiolipin, far less than that required for liposome permeabilization, despite their responsiveness to Bcl-2 family proteins. Strikingly, the incorporation of isolated mitochondrial outer membrane (MOM) proteins into liposomes lacking cardiolipin conferred responsiveness to cleaved Bid and Bax. Cardiolipin dependence was observed only when permeabilization was induced with cleaved Bid but not with Bid or Bim BH3 peptide or oligomerized Bax. Therefore, we conclude that MOM proteins specifically assist cleaved Bid in Bax-mediated permeabilization. Cryoelectron microscopy of cardiolipin-liposomes revealed that cleaved Bid and Bax produced large round holes with diameters of 25–100 nm, suggestive of lipidic pores. In sum, we propose that activated Bax induces lipidic pore formation and that MOM proteins assist cleaved Bid in this process in the absence of cardiolipin. PMID:19244344

  11. Evaluation of Novel Polyunsaturated Fatty Acid Derived Lipid Mediators of Inflammation to Ameliorate the Deleterious Effects of Blast Over Pressure on Eye and Brain Visual Processing Centers in Rats

    DTIC Science & Technology

    2015-08-01

    removal; and thus, they promote wound healing by moving an acute injury state toward a resolution phase, as opposed to entering a chronic state leading...The analysis was done to look for drug toxicity towards the white blood cells, kidneys, and liver . It is well known that these drugs work by...all blood cell types or other biochemical markers, especially those of kidney and liver function (e.g., aspartate transaminase and urea nitrogen

  12. The Regulation of Proresolving Lipid Mediator Profiles in Baboon Pneumonia by Inhaled Carbon Monoxide

    PubMed Central

    Dalli, Jesmond; Kraft, Bryan D.; Colas, Romain A.; Shinohara, Masakazu; Fredenburgh, Laura E.; Hess, Dean R.; Chiang, Nan; Welty-Wolf, Karen; Choi, Augustine M.; Piantadosi, Claude A.

    2015-01-01

    Strategies for the treatment of bacterial pneumonia beyond traditional antimicrobial therapy have been limited. The recently discovered novel genus of lipid mediators, coined “specialized proresolving mediators” (SPMs), which orchestrate clearance of recruited leukocytes and restore epithelial barrier integrity, have offered new insight into the resolution of inflammation. We performed lipid mediator (LM) metabololipidomic profiling and identification of LMs on peripheral blood leukocytes and plasma from a baboon model of Streptococcus pneumoniae pneumonia. Leukocytes and plasma were isolated from whole blood of S. pneumoniae–infected (n = 5–6 per time point) and control, uninfected baboons (n = 4 per time point) at 0, 24, 48, and 168 hours. In a subset of baboons with pneumonia (n = 3), we administered inhaled carbon monoxide (CO) at 48 hours (200–300 ppm for 60–90 min). Unstimulated leukocytes from control animals produced a proresolving LM signature with elevated resolvins and lipoxins. In contrast, serum-treated, zymosan-stimulated leukocytes and leukocytes from baboons with S. pneumoniae pneumonia produced a proinflammatory LM signature profile with elevated leukotriene B4 and prostaglandins. Plasma from baboons with S. pneumoniae pneumonia also displayed significantly reduced LM–SPM levels, including eicosapentaenoic acid–derived E-series resolvins (RvE) and lipoxins. CO inhalation increased levels of plasma RvE and lipoxins relative to preexposure levels. These results establish the leukocyte and plasma LM profiles biosynthesized during S. pneumoniae pneumonia in baboons and provide evidence for pneumonia-induced dysregulation of these proresolution programs. Moreover, these SPM profiles are partially restored with inhaled low-dose CO and SPM, which may shorten the time to pneumonia resolution. PMID:25568926

  13. Membrane lipid peroxidation in copper alloy-mediated contact killing of Escherichia coli.

    PubMed

    Hong, Robert; Kang, Tae Y; Michels, Corinne A; Gadura, Nidhi

    2012-03-01

    Copper alloy surfaces are passive antimicrobial sanitizing agents that kill bacteria, fungi, and some viruses. Studies of the mechanism of contact killing in Escherichia coli implicate the membrane as the target, yet the specific component and underlying biochemistry remain unknown. This study explores the hypothesis that nonenzymatic peroxidation of membrane phospholipids is responsible for copper alloy-mediated surface killing. Lipid peroxidation was monitored with the thiobarbituric acid-reactive substances (TBARS) assay. Survival, TBARS levels, and DNA degradation were followed in cells exposed to copper alloy surfaces containing 60 to 99.90% copper or in medium containing CuSO(4). In all cases, TBARS levels increased with copper exposure levels. Cells exposed to the highest copper content alloys, C11000 and C24000, exhibited novel characteristics. TBARS increased immediately at a very rapid rate but peaked at about 30 min. This peak was associated with the period of most rapid killing, loss in membrane integrity, and DNA degradation. DNA degradation is not the primary cause of copper-mediated surface killing. Cells exposed to the 60% copper alloy for 60 min had fully intact genomic DNA but no viable cells. In a fabR mutant strain with increased levels of unsaturated fatty acids, sensitivity to copper alloy surface-mediated killing increased, TBARS levels peaked earlier, and genomic DNA degradation occurred sooner than in the isogenic parental strain. Taken together, these results suggest that copper alloy surface-mediated killing of E. coli is triggered by nonenzymatic oxidative damage of membrane phospholipids that ultimately results in the loss of membrane integrity and cell death.

  14. Membrane Lipid Peroxidation in Copper Alloy-Mediated Contact Killing of Escherichia coli

    PubMed Central

    Hong, Robert; Kang, Tae Y.; Michels, Corinne A.

    2012-01-01

    Copper alloy surfaces are passive antimicrobial sanitizing agents that kill bacteria, fungi, and some viruses. Studies of the mechanism of contact killing in Escherichia coli implicate the membrane as the target, yet the specific component and underlying biochemistry remain unknown. This study explores the hypothesis that nonenzymatic peroxidation of membrane phospholipids is responsible for copper alloy-mediated surface killing. Lipid peroxidation was monitored with the thiobarbituric acid-reactive substances (TBARS) assay. Survival, TBARS levels, and DNA degradation were followed in cells exposed to copper alloy surfaces containing 60 to 99.90% copper or in medium containing CuSO4. In all cases, TBARS levels increased with copper exposure levels. Cells exposed to the highest copper content alloys, C11000 and C24000, exhibited novel characteristics. TBARS increased immediately at a very rapid rate but peaked at about 30 min. This peak was associated with the period of most rapid killing, loss in membrane integrity, and DNA degradation. DNA degradation is not the primary cause of copper-mediated surface killing. Cells exposed to the 60% copper alloy for 60 min had fully intact genomic DNA but no viable cells. In a fabR mutant strain with increased levels of unsaturated fatty acids, sensitivity to copper alloy surface-mediated killing increased, TBARS levels peaked earlier, and genomic DNA degradation occurred sooner than in the isogenic parental strain. Taken together, these results suggest that copper alloy surface-mediated killing of E. coli is triggered by nonenzymatic oxidative damage of membrane phospholipids that ultimately results in the loss of membrane integrity and cell death. PMID:22247141

  15. Lipid rafts and raft-mediated supramolecular entities in the regulation of CD95 death receptor apoptotic signaling.

    PubMed

    Gajate, Consuelo; Mollinedo, Faustino

    2015-05-01

    Membrane lipid rafts are highly ordered membrane domains enriched in cholesterol, sphingolipids and gangliosides that have the property to segregate and concentrate proteins. Lipid and protein composition of lipid rafts differs from that of the surrounding membrane, thus providing sorting platforms and hubs for signal transduction molecules, including CD95 death receptor-mediated signaling. CD95 can be recruited to rafts in a reversible way through S-palmitoylation following activation of cells with its physiological cognate ligand as well as with a wide variety of inducers, including several antitumor drugs through ligand-independent intracellular mechanisms. CD95 translocation to rafts can be modulated pharmacologically, thus becoming a target for the treatment of apoptosis-defective diseases, such as cancer. CD95-mediated signaling largely depends on protein-protein interactions, and the recruitment and concentration of CD95 and distinct downstream apoptotic molecules in membrane raft domains, forming raft-based supramolecular entities that act as hubs for apoptotic signaling molecules, favors the generation and amplification of apoptotic signals. Efficient CD95-mediated apoptosis involves CD95 and raft internalization, as well as the involvement of different subcellular organelles. In this review, we briefly summarize and discuss the involvement of lipid rafts in the regulation of CD95-mediated apoptosis that may provide a new avenue for cancer therapy.

  16. [Influence of ecdysteron-80 on the hormonal-mediator balance and lipid metabolism in rats with chronic cardiac failure].

    PubMed

    Fedorov, V N; Pynegova, N V

    2009-01-01

    Administration of ecdysteron-80 made of Serratula coronata L. to rats with experimental chronic cardiac failure partially corrects hormonal and mediator imbalance typical for this pathology. By some parameters this correction is full. By improving lipid metabolism, ecdysteron-80 reduces blood plasma atherogenicity.

  17. Maresin 1, a Proresolving Lipid Mediator, Mitigates Carbon Tetrachloride-Induced Liver Injury in Mice

    PubMed Central

    Li, Ruidong; Wang, Yaxin; Zhao, Ende; Wu, Ke; Li, Wei; Shi, Liang; Wang, Di; Xie, Gengchen; Yin, Yuping; Deng, Meizhou; Zhang, Peng; Tao, Kaixiong

    2016-01-01

    Maresin 1 (MaR 1) was recently reported to have protective properties in several different animal models of acute inflammation by inhibiting inflammatory response. However, its function in acute liver injury is still unknown. To address this question, we induced liver injury in BALB/c mice with intraperitoneal injection of carbon tetrachloride with or without treatment of MaR 1. Our data showed that MaR 1 attenuated hepatic injury, oxidative stress, and lipid peroxidation induced by carbon tetrachloride, as evidenced by increased thiobarbituric acid reactive substances and reactive oxygen species levels were inhibited by treatment of MaR 1. Furthermore, MaR 1 increased activities of antioxidative mediators in carbon tetrachloride-treated mice liver. MaR 1 decreased indices of inflammatory mediators such as tumor necrosis factor-α, interleukin-6, interleukin-1β, monocyte chemotactic protein 1, myeloperoxidase, cyclooxygenase-2, and inducible nitric oxide synthase. Administration of MaR 1 inhibited activation of nuclear factor kappa B (NF-κb) and mitogen-activated protein kinases (MAPKs) in the liver of CCl4 treated mice. In conclusion, these results suggested the antioxidative, anti-inflammatory properties of MaR 1 in CCl4 induced liver injury. The possible mechanism is partly implicated in its abilities to inhibit ROS generation and activation of NF-κb and MAPK pathway. PMID:26881046

  18. Effect of 4-hydroxy-2-nonenal on myoglobin-mediated lipid oxidation when varying histidine content and hemin affinity.

    PubMed

    Grunwald, Eric W; Tatiyaborworntham, Nantawat; Faustman, Cameron; Richards, Mark P

    2017-07-15

    The compound 4-hydroxy-2-nonenal (HNE) dissolved in water was examined to remove potential effects of using ethanol to solubilize the aldehyde such as altering protein structure or redox properties of myoglobin (Mb). HNE became covalently bound to sperm whale Mb at up to five sites based on ESI-MS analysis. Adducted Mb promoted lipid oxidation in washed muscle more effectively than non-adducted Mb. Alkylation of P88H/Q152HMb with HNE accelerated metMb formation and subsequent lipid oxidation. P88H/Q152HMb exposed to HNE enhanced lipid oxidation compared to wild-type Mb exposed to HNE. Results using H97A Mb suggested that the combination of HNE and low hemin affinity facilitated rapid decomposition of preformed lipid hydroperoxides to secondary lipid oxidation products. HNE and HHE (4-hydroxy-2-hexenal) facilitated Mb-mediated lipid oxidation similarly. The potential mechanisms by which Mb binding of α,β-unsaturated aldehydes affect Mb oxidation and the onset of lipid oxidation are discussed.

  19. Identification and signature profiles for pro-resolving and inflammatory lipid mediators in human tissue

    PubMed Central

    Colas, Romain A.; Shinohara, Masakazu; Dalli, Jesmond; Chiang, Nan

    2014-01-01

    Resolution of acute inflammation is an active process locally controlled by a novel genus of specialized pro-resolving mediators (SPM) that orchestrate key resolution responses. Hence, it is of general interest to identify individual bioactive mediators and profile their biosynthetic pathways with related isomers as well as their relation(s) to classic eicosanoids in mammalian tissues. Lipid mediator (LM)-SPM levels and signature profiles of their biosynthetic pathways were investigated using liquid chromatography-tandem mass spectrometry (LC-MS-MS)-based LM metabololipidomics. LM and SPM were identified using ≥6 diagnostic ions and chromatographic behavior matching with both authentic and synthetic materials. This approach was validated using the composite reference plasma (SRM1950) of 100 healthy individuals. Using targeted LM metabololipidomics, we profiled LM and SPM pathways in human peripheral blood (plasma and serum) and lymphoid organs. In these, we identified endogenous SPM metabolomes, namely, the potent lipoxins (LX), resolvins (Rv), protectins (PD), and maresins (MaR). These included RvD1, RvD2, RvD3, MaR1, and NPD1/PD1, which were identified in amounts within their bioactive ranges. In plasma and serum, principal component analysis (PCA) identified signature profiles of eicosanoids and SPM clusters. Plasma-SPM increased with omega-3 and acetylsalicylic acid intake that correlated with increased phagocytosis of Escherichia coli in whole blood. These findings demonstrate an approach for identification of SPM pathways (e.g., resolvins, protectins, and maresins) in human blood and lymphoid tissues that were in amounts commensurate with their pro-resolving, organ protective, and tissue regeneration functions. LM metabololipidomics coupled with calibration tissues and physiological changes documented herein provide a tool for functional phenotypic profiling. PMID:24696140

  20. Activation of autophagy in macrophages by pro-resolving lipid mediators

    PubMed Central

    Prieto, Patricia; Rosales-Mendoza, César Eduardo; Terrón, Verónica; Toledano, Víctor; Cuadrado, Antonio; López-Collazo, Eduardo; Bannenberg, Gerard; Martín-Sanz, Paloma; Fernández-Velasco, María; Boscá, Lisardo

    2015-01-01

    The resolution of inflammation is an active process driven by specialized pro-resolving lipid mediators, such as 15-epi-LXA4 and resolvin D1 (RvD1), that promote tissue regeneration. Macrophages regulate the innate immune response being key players during the resolution phase to avoid chronic inflammatory pathologies. Their half-life is tightly regulated to accomplish its phagocytic function, allowing the complete cleaning of the affected area. The balance between apoptosis and autophagy appears to be essential to control the survival of these immune cells within the inflammatory context. In the present work, we demonstrate that 15-epi-LXA4 and RvD1 at nanomolar concentrations promote autophagy in murine and human macrophages. Both compounds induced the MAP1LC3-I to MAP1LC3-II processing and the degradation of SQSTM1 as well as the formation of MAP1LC3+ autophagosomes, a typical signature of autophagy. Furthermore, 15-epi-LXA4 and RvD1 treatment favored the fusion of the autophagosomes with lysosomes, allowing the final processing of the autophagic vesicles. This autophagic response involves the activation of MAPK1 and NFE2L2 pathways, but by an MTOR-independent mechanism. Moreover, these pro-resolving lipids improved the phagocytic activity of macrophages via NFE2L2. Therefore, 15-epi-LXA4 and RvD1 improved both survival and functionality of macrophages, which likely supports the recovery of tissue homeostasis and avoiding chronic inflammatory diseases. PMID:26506892

  1. Activation of autophagy in macrophages by pro-resolving lipid mediators.

    PubMed

    Prieto, Patricia; Rosales-Mendoza, César Eduardo; Terrón, Verónica; Toledano, Víctor; Cuadrado, Antonio; López-Collazo, Eduardo; Bannenberg, Gerard; Martín-Sanz, Paloma; Fernández-Velasco, María; Boscá, Lisardo

    2015-01-01

    The resolution of inflammation is an active process driven by specialized pro-resolving lipid mediators, such as 15-epi-LXA4 and resolvin D1 (RvD1), that promote tissue regeneration. Macrophages regulate the innate immune response being key players during the resolution phase to avoid chronic inflammatory pathologies. Their half-life is tightly regulated to accomplish its phagocytic function, allowing the complete cleaning of the affected area. The balance between apoptosis and autophagy appears to be essential to control the survival of these immune cells within the inflammatory context. In the present work, we demonstrate that 15-epi-LXA4 and RvD1 at nanomolar concentrations promote autophagy in murine and human macrophages. Both compounds induced the MAP1LC3-I to MAP1LC3-II processing and the degradation of SQSTM1 as well as the formation of MAP1LC3(+) autophagosomes, a typical signature of autophagy. Furthermore, 15-epi-LXA4 and RvD1 treatment favored the fusion of the autophagosomes with lysosomes, allowing the final processing of the autophagic vesicles. This autophagic response involves the activation of MAPK1 and NFE2L2 pathways, but by an MTOR-independent mechanism. Moreover, these pro-resolving lipids improved the phagocytic activity of macrophages via NFE2L2. Therefore, 15-epi-LXA4 and RvD1 improved both survival and functionality of macrophages, which likely supports the recovery of tissue homeostasis and avoiding chronic inflammatory diseases.

  2. Ex Vivo Antioxidant Activity of Selected Medicinal Plants against Fenton Reaction-Mediated Oxidation of Biological Lipid Substrates

    PubMed Central

    Pai Kotebagilu, Namratha; Reddy Palvai, Vanitha; Urooj, Asna

    2015-01-01

    Free radical-mediated oxidation is often linked to various degenerative diseases. Biological substrates with lipids as major components are susceptible to oxygen-derived lipid peroxidation due to their composition. Lipid peroxide products act as biomarkers in evaluating the antioxidant potential of various plants and functional foods. The study focused on evaluation of the antioxidant potential of two extracts (methanol and 80% methanol) of four medicinal plants, Andrographis paniculata, Costus speciosus, Canthium parviflorum, and Abrus precatorius, against Fenton reaction-mediated oxidation of three biological lipid substrates; cholesterol, low-density lipoprotein, and brain homogenate. The antioxidant activity of the extracts was measured by thiobarbituric acid reactive substances method. Also, the correlation between the polyphenol, flavonoid content, and the antioxidant activity in biological substrates was analyzed. Results indicated highest antioxidant potential by 80% methanol extract of Canthium parviflorum (97.55%), methanol extract of Andrographis paniculata (72.15%), and methanol extract of Canthium parviflorum (49.55%) in cholesterol, low-density lipoprotein, and brain, respectively. The polyphenol and flavonoid contents of methanol extract of Andrographis paniculata in cholesterol (r = 0.816) and low-density lipoprotein (r = 0.948) and Costus speciosus in brain (r = 0.977, polyphenols, and r = 0.949, flavonoids) correlated well with the antioxidant activity. The findings prove the antioxidant potential of the selected medicinal plants against Fenton reaction in biological lipid substrates. PMID:26933511

  3. STAT3 promotes CD1d-mediated lipid antigen presentation by regulating a critical gene in glycosphingolipid biosynthesis.

    PubMed

    Iyer, Abhirami K; Liu, Jianyun; Gallo, Richard M; Kaplan, Mark H; Brutkiewicz, Randy R

    2015-11-01

    Cytokines that regulate the immune response signal through the Janus kinase / signal transducer and activation of transcription (JAK/STAT) pathway, but whether this pathway can regulate CD1d-mediated lipid antigen presentation to natural killer T (NKT) cells is unknown. Here, we found that STAT3 promotes antigen presentation by CD1d. Antigen-presenting cells (APCs) in which STAT3 expression was inhibited exhibited markedly reduced endogenous lipid antigen presentation to NKT cells without an impact on exogenous lipid antigen presentation by CD1d. Consistent with this observation, in APCs where STAT3 was knocked down, dramatically decreased levels of UDP glucose ceramide glucosyltransferase (UGCG), an enzyme involved in the first step of glycosphingolipid biosynthesis, were observed. Impaired lipid antigen presentation was reversed by ectopic expression of UGCG in STAT3-silenced CD1d(+) APCs. Hence, by controlling a fundamental step in CD1d-mediated lipid antigen presentation, STAT3 signalling promotes innate immune responses driven by CD1d.

  4. Silencing of lipid metabolism genes through IRE1α-mediated mRNA decay lowers plasma lipids in mice.

    PubMed

    So, Jae-Seon; Hur, Kyu Yeon; Tarrio, Margarite; Ruda, Vera; Frank-Kamenetsky, Maria; Fitzgerald, Kevin; Koteliansky, Victor; Lichtman, Andrew H; Iwawaki, Takao; Glimcher, Laurie H; Lee, Ann-Hwee

    2012-10-03

    XBP1 is a key regulator of the unfolded protein response (UPR), which is involved in a wide range of physiological and pathological processes. XBP1 ablation in liver causes profound hypolipidemia in mice, highlighting its critical role in lipid metabolism. XBP1 deficiency triggers feedback activation of its upstream enzyme IRE1α, instigating regulated IRE1-dependent decay (RIDD) of cytosolic mRNAs. Here, we identify RIDD as a crucial control mechanism of lipid homeostasis. Suppression of RIDD by RNA interference or genetic ablation of IRE1α reversed hypolipidemia in XBP1-deficient mice. Comprehensive microarray analysis of XBP1 and/or IRE1α-deficient liver identified genes involved in lipogenesis and lipoprotein metabolism as RIDD substrates, which might contribute to the suppression of plasma lipid levels by activated IRE1α. Ablation of XBP1 ameliorated hepatosteatosis, liver damage, and hypercholesterolemia in dyslipidemic animal models, suggesting that direct targeting of either IRE1α or XBP1 might be a feasible strategy to treat dyslipidemias.

  5. Central mechanisms mediating the hypophagic effects of oleoylethanolamide and N-acylphosphatidylethanolamines: different lipid signals?

    PubMed Central

    Romano, Adele; Tempesta, Bianca; Provensi, Gustavo; Passani, Maria B.; Gaetani, Silvana

    2015-01-01

    The spread of “obesity epidemic” and the poor efficacy of many anti-obesity therapies in the long-term highlight the need to develop novel efficacious therapy. This necessity stimulates a large research effort to find novel mechanisms controlling feeding and energy balance. Among these mechanisms a great deal of attention has been attracted by a family of phospholipid-derived signaling molecules that play an important role in the regulation of food-intake. They include N-acylethanolamines (NAEs) and N-acylphosphatidylethanolamines (NAPEs). NAPEs have been considered for a long time simply as phospholipid precursors of the lipid mediator NAEs, but increasing body of evidence suggest a role in many physiological processes including the regulation of feeding behavior. Several observations demonstrated that among NAEs, oleoylethanolamide (OEA) acts as a satiety signal, which is generated in the intestine, upon the ingestion of fat, and signals to the central nervous system. At this level different neuronal pathways, including oxytocinergic, noradrenergic, and histaminergic neurons, seem to mediate its hypophagic action. Similarly to NAEs, NAPE (with particular reference to the N16:0 species) levels were shown to be regulated by the fed state and this finding was initially interpreted as fluctuations of NAE precursors. However, the observation that exogenously administered NAPEs are able to inhibit food intake, not only in normal rats and mice but also in mice lacking the enzyme that converts NAPEs into NAEs, supported the hypothesis of a role of NAPE in the regulation of feeding behavior. Indirect observations suggest that the hypophagic action of NAPEs might involve central mechanisms, although the molecular target remains unknown. The present paper reviews the role that OEA and NAPEs play in the mechanisms that control food intake, further supporting this group of phospholipids as optimal candidate for the development of novel anti-obesity treatments. PMID

  6. Metformin reduces lipid accumulation in macrophages by inhibiting FOXO1-mediated transcription of fatty acid-binding protein 4

    SciTech Connect

    Song, Jun; Ren, Pingping; Zhang, Lin; Wang, Xing Li; Chen, Li; Shen, Ying H.

    2010-02-26

    Objective: The accumulation of lipids in macrophages contributes to the development of atherosclerosis. Strategies to reduce lipid accumulation in macrophages may have therapeutic potential for preventing and treating atherosclerosis and cardiovascular complications. The antidiabetic drug metformin has been reported to reduce lipid accumulation in adipocytes. In this study, we examined the effects of metformin on lipid accumulation in macrophages and investigated the mechanisms involved. Methods and results: We observed that metformin significantly reduced palmitic acid (PA)-induced intracellular lipid accumulation in macrophages. Metformin promoted the expression of carnitine palmitoyltransferase I (CPT-1), while reduced the expression of fatty acid-binding protein 4 (FABP4) which was involved in PA-induced lipid accumulation. Quantitative real-time PCR showed that metformin regulates FABP4 expression at the transcriptional level. We identified forkhead transcription factor FOXO1 as a positive regulator of FABP4 expression. Inhibiting FOXO1 expression with FOXO1 siRNA significantly reduced basal and PA-induced FABP4 expression. Overexpression of wild-type FOXO1 and constitutively active FOXO1 significantly increased FABP4 expression, whereas dominant negative FOXO1 dramatically decreased FABP4 expression. Metformin reduced FABP4 expression by promoting FOXO1 nuclear exclusion and subsequently inhibiting its activity. Conclusions: Taken together, these results suggest that metformin reduces lipid accumulation in macrophages by repressing FOXO1-mediated FABP4 transcription. Thus, metformin may have a protective effect against lipid accumulation in macrophages and may serve as a therapeutic agent for preventing and treating atherosclerosis in metabolic syndrome.

  7. Palladium(III)-Catalyzed Fluorination of Arylboronic Acid Derivatives

    PubMed Central

    Tang, Pingping; Murphy, Jennifer M.; Ritter, Tobias

    2013-01-01

    A practical, palladium-catalyzed synthesis of aryl fluorides from arylboronic acid derivatives is presented. The reaction is operationally simple and amenable to multi-gram-scale synthesis. Evaluation of the reaction mechanism suggests a single-electron-transfer pathway, involving a Pd(III) intermediate that has been isolated and characterized. PMID:24040932

  8. Palladium(III)-catalyzed fluorination of arylboronic acid derivatives.

    PubMed

    Mazzotti, Anthony R; Campbell, Michael G; Tang, Pingping; Murphy, Jennifer M; Ritter, Tobias

    2013-09-25

    A practical, palladium-catalyzed synthesis of aryl fluorides from arylboronic acid derivatives is presented. The reaction is operationally simple and amenable to multigram-scale synthesis. Evaluation of the reaction mechanism suggests a single-electron-transfer pathway, involving a Pd(III) intermediate that has been isolated and characterized.

  9. A new flavellagic acid derivative and phloroglucinol from Rhodomyrtus tomentosa.

    PubMed

    Hiranrat, A; Chitbankluoi, W; Mahabusarakam, W; Limsuwan, S; Voravuthikunchai, S P

    2012-01-01

    A new flavellagic acid derivative, 3,3',4,4'-tetra-O-methylflavellagic acid and six known compounds were isolated from the stems of Rhodomyrtus tomentosa while a new phloroglucinol, named rhodomyrtosone I, and six known compounds were isolated from the fruit. Their structures were elucidated by spectroscopic analyses as well as by comparisons with related compounds.

  10. Caffeic Acid Derivatives in Dried Lamiaceae and Echinacea purpurea Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The concentrations of caffeic acid derivatives within Lamiaceae and Echinacea (herb, spice, tea, and dietary supplement forms) readily available in the U.S. marketplace (n=72) were determined. After the first identification of chicoric acid in Ocimum basilicum (basil), the extent to which chicoric a...

  11. Transferrin mediated solid lipid nanoparticles containing curcumin: enhanced in vitro anticancer activity by induction of apoptosis.

    PubMed

    Mulik, Rohit S; Mönkkönen, Jukka; Juvonen, Risto O; Mahadik, Kakasaheb R; Paradkar, Anant R

    2010-10-15

    Photodegradation and low bioavailability are major hurdles for the therapeutic use of curcumin. Aim of the present study was to formulate transferrin-mediated solid lipid nanoparticles (Tf-C-SLN) to increase photostability, and enhance its anticancer activity against MCF-7 breast cancer cells. Tf-C-SLN were prepared by homogenization method and characterized by size, zeta potential, entrapment efficiency and stability, transmission electron microscopy (TEM), X-ray diffraction (XRD) and in vitro release study. Microplate analysis and flow cytometry techniques were used for cytotoxicity and apoptosis study. The physical characterization showed the suitability of method of preparation. TEM and XRD study revealed the spherical nature and entrapment of curcumin in amorphous form, respectively. The cytotoxicity, ROS and cell uptake was found to be increased considerably with Tf-C-SLN compared to curcumin solubilized surfactant solution (CSSS) and curcumin-loaded SLN (C-SLN) suggesting the targeting effect. AnnexinV-FITC/PI double staining, DNA analysis and reduced mitochondrial potential confirmed the apoptosis. The flow cytometric studies revealed that the anticancer activity of curcumin is enhanced with Tf-C-SLN compared to CSSS and C-SLN, and apoptosis is the mechanism underlying the cytotoxicity. The present study indicated the potential of Tf-C-SLN in enhancing the anticancer effect of curcumin in breast cancer cells in vitro.

  12. Mechanosensitivity is mediated directly by the lipid membrane in TRAAK and TREK1 K+ channels

    PubMed Central

    Brohawn, Stephen G.; Su, Zhenwei; MacKinnon, Roderick

    2014-01-01

    Mechanosensitive ion channels underlie neuronal responses to physical forces in the sensation of touch, hearing, and other mechanical stimuli. The fundamental basis of force transduction in eukaryotic mechanosensitive ion channels is unknown. Are mechanical forces transmitted directly from membrane to channel as in prokaryotic mechanosensors or are they mediated through macromolecular tethers attached to the channel? Here we show in cells that the K+ channel TRAAK (K2P4.1) is responsive to mechanical forces similar to the ion channel Piezo1 and that mechanical activation of TRAAK can electrically counter Piezo1 activation. We then show that the biophysical origins of force transduction in TRAAK and TREK1 (K2P2.1) two-pore domain K+ (K2P) channels come from the lipid membrane, not from attached tethers. These findings extend the “force-from-lipid” principle established for prokaryotic mechanosensitive channels MscL and MscS to these eukaryotic mechanosensitive K+ channels. PMID:24550493

  13. Ceramide mediates nanovesicle shedding and cell death in response to phosphatidylinositol ether lipid analogs and perifosine

    PubMed Central

    Gills, J J; Zhang, C; Abu-Asab, M S; Castillo, S S; Marceau, C; LoPiccolo, J; Kozikowski, A P; Tsokos, M; Goldkorn, T; Dennis, P A

    2012-01-01

    Anticancer phospholipids that inhibit Akt such as the alkylphospholipid perifosine (Per) and phosphatidylinositol ether lipid analogs (PIAs) promote cellular detachment and apoptosis and have a similar cytotoxicity profile against cancer cell lines in the NCI60 panel. While investigating the mechanism of Akt inhibition, we found that short-term incubation with these compounds induced rapid shedding of cellular nanovesicles containing EGFR, IGFR and p-Akt that occurred in vitro and in vivo, while prolonged incubation led to cell detachment and death that depended on sphingomyelinase-mediated generation of ceramide. Pretreatment with sphingomyelinase inhibitors blocked ceramide generation, decreases in phospho-Akt, nanovesicle release and cell detachment in response to alkylphospholipids and PIAs in non-small cell lung cancer cell lines. Similarly, exogenous ceramide also decreased active Akt and induced nanovesicle release. Knockdown of neutral sphingomyelinase decreased, whereas overexpression of neutral or acid sphingomyelinase increased cell detachment and death in response to the compounds. When transferred in vitro, PIA or Per-induced nanovesicles increased ceramide levels and death in recipient cells. These results indicate ceramide generation underlies the Akt inhibition and cytotoxicity of this group of agents, and suggests nanovesicle shedding and uptake might potentially propagate their cytotoxicity in vivo. PMID:22764099

  14. Estrogen negatively regulates epithelial wound healing and protective lipid mediator circuits in the cornea.

    PubMed

    Wang, Samantha B; Hu, Kyle M; Seamon, Kyle J; Mani, Vinidhra; Chen, Yangdi; Gronert, Karsten

    2012-04-01

    Estrogen receptors (ERs) are expressed in leukocytes and in every ocular tissue. However, sex-specific differences and the role of estradiol in ocular inflammatory-reparative responses are not well understood. We found that female mice exhibited delayed corneal epithelial wound closure and attenuated polymorphonuclear (PMN) leukocyte responses, a phenotype recapitulated by estradiol treatment both in vivo (topically in male mice) and in vitro (corneal epithelial cell wound healing). The cornea expresses 15-lipoxygenase (15-LOX) and receptors for lipoxin A(4) (LXA(4)), which have been implicated in an intrinsic lipid circuit that regulates corneal inflammation and wound healing. Delayed epithelial wound healing correlated with lower expression of 15-LOX in the regenerated epithelium of female mice. Estradiol in vitro and in vivo down-regulated epithelial 15-LOX expression and LXA(4) formation, while estradiol abrogation of epithelial wound healing was completely reversed by treatment with LXA(4). More important, ERβ and ERα selectively regulated epithelial wound healing, PMN cell recruitment, and activity of the intrinsic 15-LOX/LXA(4) circuit. Our results demonstrate for the first time a sex-specific difference in the corneal reparative response, which is mediated by ERβ and ERα selective regulation of the epithelial and PMN 15-LOX/LXA(4) circuit. These findings may provide novel insights into the etiology of sex-specific ocular inflammatory diseases.

  15. The effect of natural antioxidants on haemoglobin-mediated lipid oxidation during enzymatic hydrolysis of cod protein.

    PubMed

    Halldorsdottir, Sigrun M; Kristinsson, Hordur G; Sveinsdottir, Holmfridur; Thorkelsson, Gudjon; Hamaguchi, Patricia Y

    2013-11-15

    Heating and changes in pH often practised during fish protein hydrolysis can cause lipid oxidation. The effect of natural antioxidants towards haemoglobin-mediated lipid oxidation during enzymatic hydrolysis of cod proteins was investigated. Different variants of a washed cod model system, containing different combinations of haemoglobin and natural antioxidants (l-ascorbic acid and Fuscus vesiculosus extract), were hydrolysed using Protease P "Amano" 6 at pH 8 and 36°C to achieve 20% degree of hydrolysis. Lipid hydroperoxides and thiobarbituric acid reactive substances (TBARS) were analysed periodically during the hydrolysis process. The in vitro antioxidant activity of the final products was investigated. Results indicate that oxidation can develop rapidly during hydrolysis and antioxidant strategies are preferable to produce good quality products. Oxidation products did not have an impact on the in vitro antioxidant activity of the hydrolysates. The natural antioxidants inhibited oxidation during hydrolysis and contributed to the antioxidant activity of the final product.

  16. High levels of endogenous lipid mediators (N-acylethanolamines) in women with chronic widespread pain during acute tissue trauma

    PubMed Central

    Ghafouri, Bijar; Ghafouri, Nazdar; Gerdle, Björn

    2016-01-01

    Although chronic widespread musculoskeletal pain is a significant health problem, the molecular mechanisms involved in developing and maintaining chronic widespread musculoskeletal pain are poorly understood. Central sensitization mechanisms maintained by stimuli from peripheral tissues such as muscle have been suggested. Lipid mediators with anti-inflammatory characteristics such as endogenous ligands of peroxisome proliferator activating receptor-α, oleoylethanolamide, and palmitoylethanolamide are suggested to regulate nociceptive transmission from peripheral locations on route towards the central nervous system. This case–control study investigates the levels of anti-inflammatory lipids in microdialysis samples collected during the first 2 h after microdialysis probe insertion and explores the association of these lipids with different pain characteristics in women with chronic widespread musculoskeletal pain (n = 17) and female healthy controls (n = 19). The levels of oleoylethanolamide, palmitoylethanolamide, and stearoylethanolamide were determined. During sampling of dialysate, pain ratings were conducted using a numeric rating scale. Pain thresholds were registered from upper and lower parts of the body. Oleoylethanolamide and stearoylethanolamide levels were significantly higher (p ≤ 0.05) in chronic widespread musculoskeletal pain at all time points. Numeric rating scale correlated with levels of stearoylethanolamide in chronic widespread musculoskeletal pain. Higher levels of lipid mediators could reflect an altered tissue reactivity in response to microdialysis probe insertion in chronic widespread musculoskeletal pain. PMID:27531672

  17. Lipid mediator metabolic profiling demonstrates differences in eicosanoid patterns in two phenotypically distinct mast cell populations[S

    PubMed Central

    Lundström, Susanna L.; Saluja, Rohit; Adner, Mikael; Haeggström, Jesper Z.; Nilsson, Gunnar; Wheelock, Craig E.

    2013-01-01

    Mast cells are inflammatory cells that play key roles in health and disease. They are distributed in all tissues and appear in two main phenotypes, connective tissue and mucosal mast cells, with differing capacities to release inflammatory mediators. A metabolic profiling approach was used to obtain a more comprehensive understanding of the ability of mast cell phenotypes to produce eicosanoids and other lipid mediators. A total of 90 lipid mediators (oxylipins) were characterized using liquid chromatography-tandem mass spectrometry (LC-MS/MS), representing the cyclooxygenase (COX), lipoxygenase (LO), and cytochrome P450 (CYP) metabolic pathways. In vitro-derived murine mucosal-like mast cells (MLMC) and connective tissue-like mast cells (CTLMC) exhibited distinct mRNA expression patterns of enzymes involved in oxylipin biosynthesis. Oxylipins produced by 5-LO and COX pathways were the predominant species in both phenotypes, with 5-LO products constituting 90 ± 2% of the CTLMCs compared with 58 ± 8% in the MLMCs. Multivariate analyses demonstrated that CTLMCs and MLMCs secrete differing oxylipin profiles at baseline and following calcium ionophore stimulation, evidencing specificity in both a time- and biosynthetic pathway-dependent manner. In addition to the COX-regulated prostaglandin PGD2 and 5-LO-regulated cysteinyl-leukotrienes (e.g., LTC4), several other mediators evidenced phenotype-specificity, which may have biological implications in mast cell-mediated regulation of inflammatory responses. PMID:23034214

  18. CALCIUM-INDUCED LIPID PEROXIDATION IS MEDIATED BY RHODNIUS HEME-BINDING PROTEIN (RHBP) AND PREVENTED BY VITELLIN.

    PubMed

    Paes, Marcia C; Silveira, Alan B; Ventura-Martins, Guilherme; Luciano, Monalisa; Coelho, Marsen G P; Todeschini, Adriane R; Bianconi, M Lucia; Atella, Georgia C; Silva-Neto, Mário A C

    2015-10-01

    Lipid peroxidation is promoted by the quasi-lipoxygenase (QL) activity of heme proteins and enhanced by the presence of free calcium. Unlike mammalian plasma, the hemolymph of Rhodnius prolixus, a vector of Chagas disease, contains both a free heme-binding protein (RHBP) and circulating lipoproteins. RHBP binds and prevents the heme groups of the proteins from participating in lipid peroxidation reactions. Herein, we show that despite being bound to RHBP, heme groups promote lipid peroxidation through a calcium-dependent QL reaction. This reaction is readily inhibited by the presence of ethylene glycol tetraacetic acid (EGTA), the antioxidant butylated hydroxytoluene or micromolar levels of the main yolk phosphoprotein vitellin (Vt). The inhibition of lipid peroxidation is eliminated by the in vitro dephosphorylation of Vt, indicating that this reaction depends on the interaction of free calcium ions with negatively charged phosphoamino acids. Our results demonstrate that calcium chelation mediated by phosphoproteins occurs via an antioxidant mechanism that protects living organisms from lipid peroxidation.

  19. Lipid-mediated transfection of normal adult human hepatocytes in primary culture.

    PubMed

    Ourlin, J C; Vilarem, M J; Daujat, M; Harricane, M C; Domergue, J; Joyeux, H; Baulieux, J; Maurel, P

    1997-04-05

    The aim of this work was to develop a procedure for the lipid-mediated transfection of DNA into normal adult human hepatocytes in culture. Cells were plated in a serum-free culture medium at various cell densities, on plastic or collagen-coated dishes, both in the absence and in the presence of epidermal growth factor (EGF). The cells were incubated for various periods of time with mixtures of DNA-lipofectin or DNA-3 beta[N-(N',N'-dimethylaminoethane)-carbamoyl] cholesterol (DC-chol) liposomes, and the efficiency of transfection was assessed by measuring the activity of reporter genes, beta-galactosidase or chloramphenicol acetyl-transferase (CAT). For comparison, similar experiments were carried out with human cell lines including HepG2, Caco-2, and WRL68. The efficiency of transfection (in percentage of cells) was not significantly different after transfection with lipofectin or DC-chol and comprised between 0.04 and 1.7% (extreme values) for different cultures. The efficiency of transfection decreased as the age or density of the culture increased and increased in cultures treated with EGF. Direct measurement of the rate of DNA synthesis suggested that the efficiency of transfection was related to the number of cells entering the S phase. Under the same conditions, the efficiency of transfection was one to two orders of magnitude greater in the three cell lines. A plasmid harboring 660 bp of the 5'-flanking region of CYP1A1 (containing two xenobiotic enhancer elements) fused upstream of the promoter of thymidine kinase and the CAT reporter gene was constructed. When this plasmid was transfected in human hepatocytes, CAT activity was induced as expected. We conclude that normal adult human hepatocytes can be transfected with exogenous DNA and that the transfected construct is regulated in the manner expected from in vivo studies.

  20. [Cardioprotective properties of new glutamic acid derivative under stress conditions].

    PubMed

    Perfilova, V N; Sadikova, N V; Berestovitskaia, V M; Vasil'eva, O S

    2014-01-01

    The effect of new glutamic acid derivative on the cardiac ino- and chronotropic functions has been studied in experiments on rats exposed to 24-hour immobilization-and-pain stress. It is established that glutamic acid derivative RGPU-238 (glufimet) at a dose of 28.7 mg/kg increases the increment of myocardial contractility and relaxation rates and left ventricular pressure in stress-tested animals by 13 1,1, 72.4, and 118.6%, respectively, as compared to the control group during the test for adrenoreactivity. Compound RGPU-238 increases the increment of the maximum intensity of myocardium functioning by 196.5 % at 30 sec of isometric workload as compared to the control group. The cardioprotective effect of compound RGPU-238 is 1.5 - 2 times higher than that of the reference drug phenibut.

  1. Acetylcholinesterase inhibitory properties of some benzoic acid derivatives

    NASA Astrophysics Data System (ADS)

    Yildiz, Melike; Kiliç, Deryanur; Ünver, Yaǧmur; Şentürk, Murat; Askin, Hakan; Küfrevioǧlu, Ömer Irfan

    2016-04-01

    Acetylcholinesterase (AChE) hydrolyses the neurotransmitter acetylcholine to acetic acid and choline. AChE inhibitors are used in treatment of several neurodegeneartive disorder and Alzheimer's disease. In the present study, inhibition of AChE with some benzoic acid derivatives were investigated. 3-Chloro-benzoic acid (1), 2-hydroxy-5-sulfobenzoic acid (2), 2-(sulfooxy) benzoic acid (3), 2-hydroxybenzoic acid (4), 2,3-dimethoxybenzoic (5), and 3,4,5-trimethoxybenzoic (6) were calculated IC50 values AChE enzyme. Kinetic investigations showed that similarly to AChE inhibitors. Benzoic acid derivatives (1-6) investigated are encouraging agents which may be used as lead molecules in order to derivative novel AChE inhibitors that might be useful in medical applications.

  2. Caffeic acid derivatives in the roots of yacon (Smallanthus sonchifolius).

    PubMed

    Takenaka, Makiko; Yan, Xiaojun; Ono, Hiroshi; Yoshida, Mitsuru; Nagata, Tadahiro; Nakanishi, Tateo

    2003-01-29

    Five caffeic acid derivatives were found in the roots of yacon, Smallanthus sonchifolius (Poepp. and Endl.) H. Robinson, Asteraceae, as the major water-soluble phenolic compounds. The structures of these compounds were determined by analysis of spectroscopic data. Two of these were chlorogenic acid (3-caffeoylquinic acid) and 3,5-dicaffeoylquinic acid, common phenolic compounds in plants of the family Asteraceae. Three were esters of caffeic acid with the hydroxy groups of aldaric acid, derived from hexose. The structure of the aldaric moiety was determined by hydrolysis and comparison of NMR spectra with those of standard aldaric acids. The compounds were novel caffeic acid esters of altraric acid: 2,4- or 3,5-dicaffeoylaltraric acid, 2,5-dicaffeoylaltraric acid, and 2,3,5- or 2,4,5-tricaffeoylaltraric acid.

  3. Lipid transport mediated by Arabidopsis TGD proteins is unidirectional from the endoplasmic reticulum to the plastid

    SciTech Connect

    Xu, C.; Moellering, E. R., Muthan, B.; Fan, J.; Benning, C.

    2010-06-01

    The transfer of lipids between the endoplasmic reticulum (ER) and the plastid in Arabidopsis involves the TRIGALACTOSYLDIACYLGLYCEROL (TGD) proteins. Lipid exchange is thought to be bidirectional based on the presence of specific lipid molecular species in Arabidopsis mutants impaired in the desaturation of fatty acids of membrane lipids in the ER and plastid. However, it was unclear whether TGD proteins were required for lipid trafficking in both directions. This question was addressed through the analysis of double mutants of tgd1-1 or tgd4-3 in genetic mutant backgrounds leading to a defect in lipid fatty acid desaturation either in the ER (fad2) or the plastid (fad6). The fad6 tgd1-1 and fad6 tgd4-3 double mutants showed drastic reductions in the relative levels of polyunsaturated fatty acids and of galactolipids. The growth of these plants and the development of photosynthetic membrane systems were severely compromised, suggesting a disruption in the import of polyunsaturated fatty acid-containing lipid species from the ER. Furthermore, a forward-genetic screen in the tgd1-2 dgd1 mutant background led to the isolation of a new fad6-2 allele with a marked reduction in the amount of digalactosyldiacylglycerol. In contrast, the introduction of fad2, affecting fatty acid desaturation of lipids in the ER, into the two tgd mutant backgrounds did not further decrease the level of fatty acid desaturation in lipids of extraplastidic membranes. These results suggest that the role of TGD proteins is limited to plastid lipid import, but does not extend to lipid export from the plastid to extraplastidic membranes.

  4. The neutral lipid composition present in the digestive vacuole of Plasmodium falciparum concentrates heme and mediates β-hematin formation with an unusually low activation energy.

    PubMed

    Hoang, Anh N; Sandlin, Rebecca D; Omar, Aneesa; Egan, Timothy J; Wright, David W

    2010-11-30

    In eukaryotic cells, neutral lipids serve as major energy storage molecules; however, in Plasmodium falciparum, a parasite responsible for causing malaria in humans, neutral lipids may have other functions during the intraerythrocytic stage of the parasite life cycle. Specifically, experimental data suggest that neutral lipid structures behave as a catalyst for the crystallization of hemozoin, a detoxification byproduct of several blood-feeding organisms, including malaria parasites. Synthetic neutral lipid droplets (SNLDs) were produced by depositing a lipid blend solution comprised of mono- and diglycerides onto an aqueous surface. These lipid droplets are able to mediate the production of brown pigments that are morphologically and chemically identical to hemozoin. The partitioning of heme into these SNLDs was examined by employing Nile Red, a lipid specific dye. Soluble ferriprotoporphyrin IX was observed to spontaneously localize to the lipid droplets, partitioning in a pH-dependent manner with an estimated log P of 2.6. Interestingly, the pH profile of heme partitioning closely resembles that of β-hematin formation. Differential scanning calorimetry and kinetic studies demonstrated that the SNLDs provide a unique environment that promotes hemozoin formation. SNLD-mediated formation of the malaria pigment displayed an activation energy barrier lower than those of individual lipid components. In particular, lipid droplets composed of diglycerides displayed activation barriers lower than those composed of monoglycerides. This difference was attributed to the greater fluidity of these lipids. In conjunction with the known pattern of lipid body proliferation, it is suggested that neutral lipid structures within the digestive vacuole not only are the location of in vivo hemozoin formation but are also essential for the survival of the parasite by functioning as a kinetically competent and site specific mediator for heme detoxification.

  5. Acyl Meldrum's acid derivatives: application in organic synthesis

    NASA Astrophysics Data System (ADS)

    Janikowska, K.; Rachoń, J.; Makowiec, S.

    2014-07-01

    This review is focused on an important class of Meldrum's acid derivatives commonly known as acyl Meldrum's acids. The preparation methods of these compounds are considered including the recently proposed and rather rarely used ones. The chemical properties of acyl Meldrum's acids are described in detail, including thermal stability and reactions with various nucleophiles. The possible mechanisms of these transformations are analyzed. The bibliography includes 134 references.

  6. Citric-acid-derived photo-cross-linked biodegradable elastomers.

    PubMed

    Gyawali, Dipendra; Tran, Richard T; Guleserian, Kristine J; Tang, Liping; Yang, Jian

    2010-01-01

    Citric-acid-derived thermally cross-linked biodegradable elastomers (CABEs) have recently received significant attention in various biomedical applications, including tissue-engineering orthopedic devices, bioimaging and implant coatings. However, citric-acid-derived photo-cross-linked biodegradable elastomers are rarely reported. Herein, we report a novel photo-cross-linked biodegradable elastomer, referred to as poly(octamethylene maleate citrate) (POMC), which preserves pendant hydroxyl and carboxylic functionalities after cross-linking for the potential conjugation of biologically active molecules. Pre-POMC is a low-molecular-mass pre-polymer with an average molecular mass between 701 and 1291 Da. POMC networks are soft and elastic with an initial modulus of 0.07 to 1.3 MPa and an elongation-at-break between 38 and 382%. FT-IR-ATR results confirmed the successful surface immobilization of type-I collagen onto POMC films, which enhanced in vitro cellular attachment and proliferation. Photo-polymerized POMC films implanted subcutaneously into Sprague-Dawley rats demonstrated minimal in vivo inflammatory responses. The development of POMC enriches the family of citric-acid-derived biodegradable elastomers and expands the available biodegradable polymers for versatile needs in biomedical applications.

  7. Chylomicron components mediate intestinal lipid-induced inhibition of gastric motor function.

    PubMed

    Glatzle, Jörg; Kalogeris, Theodore J; Zittel, Tilman T; Guerrini, Stephania; Tso, Patrick; Raybould, Helen E

    2002-01-01

    Lipid, particularly long-chain triglyceride, initiates feedback regulation of gastrointestinal function. To determine whether the site of action of lipid is pre- or postabsorptive, we investigated the ability of mesenteric lipid-fed lymph to inhibit gastric motor function. Lymph was collected from awake lymph-fistula rats during intestinal infusion with either a glucose-saline maintenance solution or lipid. Intra-arterial injection of lymph collected during intestinal lipid infusion significantly inhibited gastric motility in anesthetized recipient rats compared with injection of equivalent amounts of triglyceride or lymph collected during intestinal infusion of maintenance solution. Lymph collected from rats during lipid infusion with Pluronic L-81 [an inhibitor of chylomicron formation and apolipoprotein (apo) A-IV secretion] compared with lymph injection from donor animals treated with Pluronic L-63 (a noninhibitory control for Pluronic L-81) was significantly less potent. Injection of purified recombinant apo A-IV significantly inhibited gastric motility. Products of lipid digestion and absorption, other than fatty acids or triglyceride, released by the intestine during lipid digestion likely serve as signals to initiate intestinal feedback regulation of gastrointestinal function. Most likely, apo A-IV is one of the signals involved.

  8. Lipid transfer protein-mediated resistance to a trichothecene mycotoxin – Novel players in FHB resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lipid transfer proteins are a class of basic cysteine rich proteins characterized by an eight cysteine motif backbone with intrinsic antimicrobial activities against bacterial and fungal pathogens. Previously, we identified two type IV nonspecific lipid transfer protein (nsLTP) genes (LTP4.4 and LTP...

  9. Efficacious gene silencing in serum and significant apoptotic activity induction by survivin downregulation mediated by new cationic gemini tocopheryl lipids.

    PubMed

    Kumar, Krishan; Maiti, Bappa; Kondaiah, Paturu; Bhattacharya, Santanu

    2015-02-02

    anticancer drug, doxorubicin, significantly. In short, the new tocopherol based gemini lipids appear to be highly promising for achieving siRNA mediated gene knockdown in various cell lines.

  10. Increased levels of palmitoylethanolamide and other bioactive lipid mediators and enhanced local mast cell proliferation in canine atopic dermatitis

    PubMed Central

    2014-01-01

    Background Despite the precise pathogenesis of atopic dermatitis (AD) is unknown, an immune dysregulation that causes Th2-predominant inflammation and an intrinsic defect in skin barrier function are currently the two major hypotheses, according to the so-called outside-inside-outside model. Mast cells (MCs) are involved in AD both by releasing Th2 polarizing cytokines and generating pruritus symptoms through release of histamine and tryptase. A link between MCs and skin barrier defects was recently uncovered, with histamine being found to profoundly contribute to the skin barrier defects. Palmitoylethanolamide and related lipid mediators are endogenous bioactive compounds, considered to play a protective homeostatic role in many tissues: evidence collected so far shows that the anti-inflammatory effect of palmitoylethanolamide depends on the down-modulation of MC degranulation. Based on this background, the purpose of the present study was twofold: (a) to determine if the endogenous levels of palmitoylethanolamide and other bioactive lipid mediators are changed in the skin of AD dogs compared to healthy animals; (b) to examine if MC number is increased in the skin of AD dogs and, if so, whether it depends on MC in-situ proliferation. Results The amount of lipid extract expressed as percent of biopsy tissue weight was significantly reduced in AD skin while the levels of all analyzed bioactive lipid mediators were significantly elevated, with palmitoylethanolamide showing the highest increase. In dogs with AD, the number of MCs was significantly increased in both the subepidermal and the perifollicular compartments and their granule content was significantly decreased in the latter. Also, in situ proliferation of MCs was documented. Conclusions The levels of palmitoylethanolamide and other bioactive lipid mediators were shown to increase in AD skin compared to healthy samples, leading to the hypothesis that they may be part of the body’s innate mechanisms to

  11. Noninvasive Imaging of Lipid Nanoparticle–Mediated Systemic Delivery of Small-Interfering RNA to the Liver

    PubMed Central

    Tao, Weikang; Davide, Joseph P; Cai, Mingmei; Zhang, Guo-Jun; South, Victoria J; Matter, Andrea; Ng, Bruce; Zhang, Ye; Sepp-Lorenzino, Laura

    2010-01-01

    Mouse models with liver-specific expression of firefly luciferase were developed that enable a noninvasive and longitudinal assessment of small-interfering RNA (siRNA)–mediated gene silencing in hepatocytes of live animals via bioluminescence imaging. Using these models, a set of lipid nanoparticles (LNPs) with different compositions of cationic lipids, polyethylene glycol (PEG), and cholesterol, were tested for their abilities in delivering a luciferase siRNA to the liver via systemic administration. A dose-dependent luciferase knockdown by LNP/siRNA assemblies was measured by in vivo bioluminescence imaging, which correlated well with the results from parallel ex vivo analyses of luciferase mRNA and protein levels in the liver. RNA interference (RNAi)–mediated target silencing was further confirmed by the detection of RNAi-specific target mRNA cleavage. A single dose of LNP02L at 3 mg/kg (siRNA) caused 90% reduction of luciferase expression and the target repression lasted for at least 10 days. With identical components, LNPs containing 2% PEG are more potent than those with 5.4% PEG. Our results demonstrate that these liver-luciferase mouse models provide a powerful tool for a high-throughput evaluation of hepatic delivery platforms by noninvasive imaging and that the molar ratio of PEG lipid can affect the efficacy of LNPs in silencing liver targets via systemic administration. PMID:20628357

  12. Noninvasive imaging of lipid nanoparticle-mediated systemic delivery of small-interfering RNA to the liver.

    PubMed

    Tao, Weikang; Davide, Joseph P; Cai, Mingmei; Zhang, Guo-Jun; South, Victoria J; Matter, Andrea; Ng, Bruce; Zhang, Ye; Sepp-Lorenzino, Laura

    2010-09-01

    Mouse models with liver-specific expression of firefly luciferase were developed that enable a noninvasive and longitudinal assessment of small-interfering RNA (siRNA)-mediated gene silencing in hepatocytes of live animals via bioluminescence imaging. Using these models, a set of lipid nanoparticles (LNPs) with different compositions of cationic lipids, polyethylene glycol (PEG), and cholesterol, were tested for their abilities in delivering a luciferase siRNA to the liver via systemic administration. A dose-dependent luciferase knockdown by LNP/siRNA assemblies was measured by in vivo bioluminescence imaging, which correlated well with the results from parallel ex vivo analyses of luciferase mRNA and protein levels in the liver. RNA interference (RNAi)-mediated target silencing was further confirmed by the detection of RNAi-specific target mRNA cleavage. A single dose of LNP02L at 3 mg/kg (siRNA) caused 90% reduction of luciferase expression and the target repression lasted for at least 10 days. With identical components, LNPs containing 2% PEG are more potent than those with 5.4% PEG. Our results demonstrate that these liver-luciferase mouse models provide a powerful tool for a high-throughput evaluation of hepatic delivery platforms by noninvasive imaging and that the molar ratio of PEG lipid can affect the efficacy of LNPs in silencing liver targets via systemic administration.

  13. Resonance-mode electrochemical impedance measurements of silicon dioxide supported lipid bilayer formation and ion channel mediated charge transport.

    PubMed

    Lundgren, Anders; Hedlund, Julia; Andersson, Olof; Brändén, Magnus; Kunze, Angelika; Elwing, Hans; Höök, Fredrik

    2011-10-15

    A single-chip electrochemical method based on impedance measurements in resonance mode has been employed to study lipid monolayer and bilayer formation on hydrophobic alkanethiolate and SiO(2) substrates, respectively. The processes were monitored by temporally resolving changes in interfacial capacitance and resistance, revealing information about the rate of formation, coverage, and defect density (quality) of the layers at saturation. The resonance-based impedance measurements were shown to reveal significant differences in the layer formation process of bilayers made from (i) positively charged lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-ethylphosphocholine (POEPC), (ii) neutral lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) on SiO(2), and (iii) monolayers made from POEPC on hydrophobic alkanethiolate substrates. The observed responses were represented with an equivalent circuit, suggesting that the differences primarily originate from the presence of a conductive aqueous layer between the lipid bilayers and the SiO(2). In addition, by adding the ion channel gramicidin D to bilayers supported on SiO(2), channel-mediated charge transport could be measured with high sensitivity (resolution around 1 pA).

  14. Lipid Nanoparticle-mediated siRNA Transfer Against PCTAIRE1/PCTK1/Cdk16 Inhibits In Vivo Cancer Growth

    PubMed Central

    Yanagi, Teruki; Tachikawa, Kiyoshi; Wilkie-Grantham, Rachel; Hishiki, Asami; Nagai, Ko; Toyonaga, Ellen; Chivukula, Pad; Matsuzawa, Shu-ichi

    2016-01-01

    PCTAIRE1/CDK16/PCTK1 plays critical roles in cancer cell proliferation and antiapoptosis. To advance our previously published in vitro results with PCTAIRE1 silencing, we examined the in vivo therapeutic potential of this approach by using small interfering RNA (siRNA) encapsulated by lipid nanoparticles. Therapy experiments of PCTAIRE1 siRNA were performed using human HCT116 colorectal cancer cells and human A2058 melanoma cells. A single dose of PCTAIRE1 siRNA-lipid nanoparticles was found to be highly effective in reducing in vivo PCTAIRE1 expression for up to 4 days as assayed by immunoblotting. Therapy experiments were started 4 days after subcutaneous injection of cancer cells. Treatment with PCTAIRE1 siRNA-lipid nanoparticles (0.5 mg/kg RNA, twice a week) reduced tumor volume and weight significantly compared with the scramble-control group. Histopathological analysis (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling) showed increased apoptosis of tumor cells treated with PCTAIRE1-siRNA. Overall, our results demonstrate that siRNA treatment targeting PCTAIRE1 is effective in vivo, suggesting that PCTAIRE1 siRNA-lipid nanoparticles might be a novel therapeutic approach against cancer cells. PMID:27351680

  15. Binding of DNA to zwitterionic lipid layers mediated by divalent cations.

    PubMed

    Mengistu, Demmelash H; Bohinc, Klemen; May, Sylvio

    2009-09-10

    Divalent cations, i.e., calcium, magnesium, and others, are able to enhance the ability of DNA to interact with membranes that are composed of zwitterionic lipids such as phosphatidylcholine. The resulting condensed complexes offer potential applications as nontoxic gene delivery vehicles. The present study suggests a generic theoretical model to describe the energetics and structural features of a zwitterionic lipid-DNA complex in the presence of divalent cations. Specifically, we consider the adsorption of a single molecule of double-stranded DNA onto a planar zwitterionic lipid layer. Our theoretical model is based on the continuum Poisson-Boltzmann formalisms, which we modified so as to account for the two opposite charges and orientational freedom of the zwitterionic lipid headgroups. We find a substantially more favorable adsorption free energy of the DNA if divalent cations are present. In addition, our model predicts the divalent cations to preferentially interact with the phosphate groups of the zwitterionic lipids, given these lipids are located in close vicinity to the DNA. This is accompanied by a small but notable reorientation of the zwitterionic headgroups toward the DNA. We demonstrate that the binding of DNA onto a zwitterionic lipid layer is not driven by the release of counterions. Instead, the binding leads to a partial redistribution of the divalent cations, from the phosphate groups of the DNA (prior to the binding) to the phosphate groups of the zwitterionic lipids (after the binding). Our results thus suggest a general physical mechanism underlying complex formation between DNA and zwitterionic lipids in terms of mean-field electrostatics, i.e., neither involving correlations nor specific interactions of the divalent cations.

  16. Carbon Monoxide Improves Efficacy of Mesenchymal Stromal Cells During Sepsis by Production of Specialized Proresolving Lipid Mediators*

    PubMed Central

    Tsoyi, Konstantin; Hall, Sean R. R.; Dalli, Jesmond; Colas, Romain A.; Ghanta, Sailaja; Ith, Bonna; Coronata, Anna; Fredenburgh, Laura E.; Baron, Rebecca M.; Choi, Augustine M. K.; Serhan, Charles N.; Liu, Xiaoli

    2016-01-01

    Objectives: Mesenchymal stromal cells are being investigated as a cell-based therapy for a number of disease processes, with promising results in animal models of systemic inflammation and sepsis. Studies are ongoing to determine ways to further improve the therapeutic potential of mesenchymal stromal cells. A gas molecule that improves outcome in experimental sepsis is carbon monoxide. We hypothesized that preconditioning of mesenchymal stromal cells with carbon monoxide ex vivo would promote further therapeutic benefit when cells are administered in vivo after the onset of polymicrobial sepsis in mice. Design: Animal study and primary cell culture. Setting: Laboratory investigation. Subjects: BALB/c mice. Interventions: Polymicrobial sepsis was induced by cecal ligation and puncture. Mesenchymal stromal cells, mesenchymal stromal cells-conditioned with carbon monoxide, fibroblasts, or fibroblasts-conditioned with carbon monoxide were delivered by tail vein injections to septic mice. The mice were assessed for survival, bacterial clearance, and the inflammatory response during sepsis in each of the groups. Mesenchymal stromal cells were also assessed for their ability to promote bacterial phagocytosis by neutrophils, the production of specialized proresolving lipid mediators, and their importance for mesenchymal stromal cells function using gene silencing. Measurements and Main Results: Ex vivo preconditioning with carbon monoxide allowed mesenchymal stromal cells to be administered later after the onset of sepsis (6 hr), and yet maintain their therapeutic effect with increased survival. Carbon monoxide preconditioned mesenchymal stromal cells were also able to alleviate organ injury, improve bacterial clearance, and promote the resolution of inflammation. Mesenchymal stromal cells exposed to carbon monoxide, with docosahexaenoic acid substrate, produced specialized proresolving lipid mediators, particularly D-series resolvins, which promoted survival. Silencing

  17. Ultrafine particles affect the balance of endogenous pro- and anti-inflammatory lipid mediators in the lung: in-vitro and in-vivo studies

    PubMed Central

    2012-01-01

    Background Exposure to ultrafine particles exerts diverse harmful effects including aggravation of pulmonary diseases like asthma. Recently we demonstrated in a mouse model for allergic airway inflammation that particle-derived oxidative stress plays a crucial role during augmentation of allergen-induced lung inflammation by ultrafine carbon particle (UfCP) inhalation. The mechanisms how particle inhalation might change the inflammatory balance in the lungs, leading to accelerated inflammatory reactions, remain unclear. Lipid mediators, known to be immediately generated in response to tissue injury, might be strong candidates for priming this particle-triggered change of the inflammatory balance. Methods We hypothesize that inhalation of UfCP may disturb the balance of pro- and anti-inflammatory lipid mediators in: i) a model for acute allergic pulmonary inflammation, exposing mice for 24 h before allergen challenge to UfCP inhalation (51.7 nm, 507 μg/m3), and ii) an in-vitro model with primary rat alveolar macrophages (AM) incubated with UfCP (10 μg/1 x 106 cells/ml) for 1 h. Lungs and AM were analysed for pro- and anti-inflammatory lipid mediators, namely leukotriene B4 (LTB4), prostaglandin E2 (PGE2), 15(S)-hydroxy-eicosatetraenoic acid (15(S)-HETE), lipoxin A4 (LXA4) and oxidative stress marker 8-isoprostane by enzyme immunoassays and immunohistochemistry. Results In non-sensitized mice UfCP exposure induced a light non-significant increase of all lipid mediators. Similarly but significantly in rat AM all lipid mediators were induced already within 1 h of UfCP stimulation. Also sensitized and challenge mice exposed to filtered air showed a partially significant increase in all lipid mediators. In sensitized and challenged mice UfCP exposure induced highest significant levels of all lipid mediators in the lungs together with the peak of allergic airway inflammation on day 7 after UfCP inhalation. The levels of LTB4, 8-isoprostane and PGE2 were significantly

  18. 21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Oleic acid derived from tall oil fatty acids. 172... FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and...

  19. 21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Oleic acid derived from tall oil fatty acids. 172... FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and...

  20. 21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Oleic acid derived from tall oil fatty acids. 172... FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and...

  1. 21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Oleic acid derived from tall oil fatty acids. 172... Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and as a component in the manufacture of...

  2. 21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Oleic acid derived from tall oil fatty acids. 172... FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and...

  3. Lipid-mediated regulation of SKN-1/Nrf in response to germ cell absence

    PubMed Central

    Steinbaugh, Michael J; Narasimhan, Sri Devi; Robida-Stubbs, Stacey; Moronetti Mazzeo, Lorenza E; Dreyfuss, Jonathan M; Hourihan, John M; Raghavan, Prashant; Operaña, Theresa N; Esmaillie, Reza; Blackwell, T Keith

    2015-01-01

    In Caenorhabditis elegans, ablation of germline stem cells (GSCs) extends lifespan, but also increases fat accumulation and alters lipid metabolism, raising the intriguing question of how these effects might be related. Here, we show that a lack of GSCs results in a broad transcriptional reprogramming in which the conserved detoxification regulator SKN-1/Nrf increases stress resistance, proteasome activity, and longevity. SKN-1 also activates diverse lipid metabolism genes and reduces fat storage, thereby alleviating the increased fat accumulation caused by GSC absence. Surprisingly, SKN-1 is activated by signals from this fat, which appears to derive from unconsumed yolk that was produced for reproduction. We conclude that SKN-1 plays a direct role in maintaining lipid homeostasis in which it is activated by lipids. This SKN-1 function may explain the importance of mammalian Nrf proteins in fatty liver disease and suggest that particular endogenous or dietary lipids might promote health through SKN-1/Nrf. DOI: http://dx.doi.org/10.7554/eLife.07836.001 PMID:26196144

  4. Conserved Amphipathic Helices Mediate Lipid Droplet Targeting of Perilipins 1–3*

    PubMed Central

    Rowe, Emily R.; Mimmack, Michael L.; Barbosa, Antonio D.; Haider, Afreen; Isaac, Iona; Ouberai, Myriam M.; Thiam, Abdou Rachid; Patel, Satish; Saudek, Vladimir; Siniossoglou, Symeon; Savage, David B.

    2016-01-01

    Perilipins (PLINs) play a key role in energy storage by orchestrating the activity of lipases on the surface of lipid droplets. Failure of this activity results in severe metabolic disease in humans. Unlike all other lipid droplet-associated proteins, PLINs localize almost exclusively to the phospholipid monolayer surrounding the droplet. To understand how they sense and associate with the unique topology of the droplet surface, we studied the localization of human PLINs in Saccharomyces cerevisiae, demonstrating that the targeting mechanism is highly conserved and that 11-mer repeat regions are sufficient for droplet targeting. Mutations designed to disrupt folding of this region into amphipathic helices (AHs) significantly decreased lipid droplet targeting in vivo and in vitro. Finally, we demonstrated a substantial increase in the helicity of this region in the presence of detergent micelles, which was prevented by an AH-disrupting missense mutation. We conclude that highly conserved 11-mer repeat regions of PLINs target lipid droplets by folding into AHs on the droplet surface, thus enabling PLINs to regulate the interface between the hydrophobic lipid core and its surrounding hydrophilic environment. PMID:26742848

  5. External lipid PI3P mediates entry of eukaryotic pathogen effectors into plant and animal host cells.

    PubMed

    Kale, Shiv D; Gu, Biao; Capelluto, Daniel G S; Dou, Daolong; Feldman, Emily; Rumore, Amanda; Arredondo, Felipe D; Hanlon, Regina; Fudal, Isabelle; Rouxel, Thierry; Lawrence, Christopher B; Shan, Weixing; Tyler, Brett M

    2010-07-23

    Pathogens of plants and animals produce effector proteins that are transferred into the cytoplasm of host cells to suppress host defenses. One type of plant pathogens, oomycetes, produces effector proteins with N-terminal RXLR and dEER motifs that enable entry into host cells. We show here that effectors of another pathogen type, fungi, contain functional variants of the RXLR motif, and that the oomycete and fungal RXLR motifs enable binding to the phospholipid, phosphatidylinositol-3-phosphate (PI3P). We find that PI3P is abundant on the outer surface of plant cell plasma membranes and, furthermore, on some animal cells. All effectors could also enter human cells, suggesting that PI3P-mediated effector entry may be very widespread in plant, animal and human pathogenesis. Entry into both plant and animal cells involves lipid raft-mediated endocytosis. Blocking PI3P binding inhibited effector entry, suggesting new therapeutic avenues.

  6. Activity of dehydroabietic acid derivatives against wood contaminant fungi.

    PubMed

    Savluchinske-Feio, Sonia; Nunes, Lina; Pereira, Pablo Tavares; Silva, Ana M; Roseiro, José C; Gigante, Bárbara; Marcelo Curto, Maria João

    2007-09-01

    The antifungal activity of 10 dehydroabietic acid derivatives with different configuration in A and B rings (cis/trans A/B junction) and different substituents and/or functionalities was evaluated in bioassays in vitro and in situ (pine wood blocks). The test compounds dissolved in acetone were assayed at several concentrations w/w (test compound/culture medium) against the fungi. The Relative Inhibition (RI) was determined by measuring the radial growth of colonies of the fungi treated with the test compounds by comparison with those of control cultures; the results are expressed as EC(50). The results of bioassays in vitro have shown that hydroxyl and aldehyde functions are required for antifungal activity in this group of compounds and deisopropylation can increase the activity. Our assay of antifungal activity in situ (in pine wood blocks) provides a means to investigate the preservative activities of these antifungal compounds under actual conditions of use. The dehydroabietic acid derivative cis-deisopropyldehydroabietanol (10) inhibited the growth of several of the fungi tested, in vitro and in situ. The results obtained in situ with the test compound (10) at 6% and 8% were not significantly different from the reference products and a good level of protection of the wood against the organisms tested was achieved. The results in wood bioassays present new possibilities in the search for natural new compounds in the wood protection, as an alternative to conventional fungicides.

  7. Plant amino acid-derived vitamins: biosynthesis and function.

    PubMed

    Miret, Javier A; Munné-Bosch, Sergi

    2014-04-01

    Vitamins are essential organic compounds for humans, having lost the ability to de novo synthesize them. Hence, they represent dietary requirements, which are covered by plants as the main dietary source of most vitamins (through food or livestock's feed). Most vitamins synthesized by plants present amino acids as precursors (B1, B2, B3, B5, B7, B9 and E) and are therefore linked to plant nitrogen metabolism. Amino acids play different roles in their biosynthesis and metabolism, either incorporated into the backbone of the vitamin or as amino, sulfur or one-carbon group donors. There is a high natural variation in vitamin contents in crops and its exploitation through breeding, metabolic engineering and agronomic practices can enhance their nutritional quality. While the underlying biochemical roles of vitamins as cosubstrates or cofactors are usually common for most eukaryotes, the impact of vitamins B and E in metabolism and physiology can be quite different on plants and animals. Here, we first aim at giving an overview of the biosynthesis of amino acid-derived vitamins in plants, with a particular focus on how this knowledge can be exploited to increase vitamin contents in crops. Second, we will focus on the functions of these vitamins in both plants and animals (and humans in particular), to unravel common and specific roles for vitamins in evolutionary distant organisms, in which these amino acid-derived vitamins play, however, an essential role.

  8. Lipid tail protrusions mediate the insertion of nanoparticles into model cell membranes

    NASA Astrophysics Data System (ADS)

    van Lehn, Reid C.; Ricci, Maria; Silva, Paulo H. J.; Andreozzi, Patrizia; Reguera, Javier; Voïtchovsky, Kislon; Stellacci, Francesco; Alexander-Katz, Alfredo

    2014-07-01

    Recent work has demonstrated that charged gold nanoparticles (AuNPs) protected by an amphiphilic organic monolayer can spontaneously insert into the core of lipid bilayers to minimize the exposure of hydrophobic surface area to water. However, the kinetic pathway to reach the thermodynamically stable transmembrane configuration is unknown. Here, we use unbiased atomistic simulations to show the pathway by which AuNPs spontaneously insert into bilayers and confirm the results experimentally on supported lipid bilayers. The critical step during this process is hydrophobic-hydrophobic contact between the core of the bilayer and the monolayer of the AuNP that requires the stochastic protrusion of an aliphatic lipid tail into solution. This last phenomenon is enhanced in the presence of high bilayer curvature and closely resembles the putative pre-stalk transition state for vesicle fusion. To the best of our knowledge, this work provides the first demonstration of vesicle fusion-like behaviour in an amphiphilic nanoparticle system.

  9. Deregulation of Hepatic Insulin Sensitivity Induced by Central Lipid Infusion in Rats Is Mediated by Nitric Oxide

    PubMed Central

    Marsollier, Nicolas; Kassis, Nadim; Mezghenna, Karima; Soty, Maud; Fioramonti, Xavier; Lacombe, Amélie; Joly, Aurélie; Pillot, Bruno; Zitoun, Carine; Vilar, José; Mithieux, Gilles; Gross, René; Lajoix, Anne-Dominique; Routh, Vanessa; Magnan, Christophe; Cruciani-Guglielmacci, Céline

    2009-01-01

    Background Deregulation of hypothalamic fatty acid sensing lead to hepatic insulin-resistance which may partly contribute to further impairment of glucose homeostasis. Methodology We investigated here whether hypothalamic nitric oxide (NO) could mediate deleterious peripheral effect of central lipid overload. Thus we infused rats for 24 hours into carotid artery towards brain, either with heparinized triglyceride emulsion (Intralipid, IL) or heparinized saline (control rats). Principal Findings Lipids infusion led to hepatic insulin-resistance partly related to a decreased parasympathetic activity in the liver assessed by an increased acetylcholinesterase activity. Hypothalamic nitric oxide synthases (NOS) activities were significantly increased in IL rats, as the catalytically active neuronal NOS (nNOS) dimers compared to controls. This was related to a decrease in expression of protein inhibitor of nNOS (PIN). Effect of IL infusion on deregulated hepatic insulin-sensitivity was reversed by carotid injection of non selective NOS inhibitor NG-monomethyl-L-arginine (L-NMMA) and also by a selective inhibitor of the nNOS isoform, 7-Nitro-Indazole (7-Ni). In addition, NO donor injection (L-arginine and SNP) within carotid in control rats mimicked lipid effects onto impaired hepatic insulin sensitivity. In parallel we showed that cultured VMH neurons produce NO in response to fatty acid (oleic acid). Conclusions/Significance We conclude that cerebral fatty acid overload induces an enhancement of nNOS activity within hypothalamus which is, at least in part, responsible fatty acid increased hepatic glucose production. PMID:19680547

  10. Rutin as a Mediator of Lipid Metabolism and Cellular Signaling Pathways Interactions in Fibroblasts Altered by UVA and UVB Radiation

    PubMed Central

    Rybałtowska-Kawałko, Paula

    2017-01-01

    Background. Rutin is a natural nutraceutical that is a promising compound for the prevention of UV-induced metabolic changes in skin cells. The aim of this study was to examine the effects of rutin on redox and endocannabinoid systems, as well as proinflammatory and proapoptotic processes, in UV-irradiated fibroblasts. Methods. Fibroblasts exposed to UVA and UVB radiation were treated with rutin. The activities and levels of oxidants/antioxidants and endocannabinoid system components, as well as lipid, DNA, and protein oxidation products, and the proinflammatory and pro/antiapoptotic proteins expression were measured. Results. Rutin reduced UV-induced proinflammatory response and ROS generation and enhanced the activity/levels of antioxidants (SOD, GSH-Px, vitamin E, GSH, and Trx). Rutin also normalized UV-induced Nrf2 expression. Its biological activity prevented changes in the levels of the lipid mediators: MDA, 4-HNE, and endocannabinoids, as well as the endocannabinoid receptors CB1/2, VR1, and GPR55 expression. Furthermore, rutin prevented the protein modifications (tyrosine derivatives formation in particular) and decreased the levels of the proapoptotic markers—caspase-3 and cytochrome c. Conclusion. Rutin prevents UV-induced inflammation and redox imbalance at protein and transcriptional level which favors lipid, protein, and DNA protection. In consequence rutin regulates endocannabinoid system and apoptotic balance. PMID:28168010

  11. Lipids as modulators of membrane fusion mediated by viral fusion proteins.

    PubMed

    Teissier, Elodie; Pécheur, Eve-Isabelle

    2007-11-01

    Enveloped viruses infect host cells by fusion of viral and target membranes. This fusion event is triggered by specific glycoproteins in the viral envelope. Fusion glycoproteins belong to either class I, class II or the newly described third class, depending upon their arrangement at the surface of the virion, their tri-dimensional structure and the location within the protein of a short stretch of hydrophobic amino acids called the fusion peptide, which is able to induce the initial lipid destabilization at the onset of fusion. Viral fusion occurs either with the plasma membrane for pH-independent viruses, or with the endosomal membranes for pH-dependent viruses. Although, viral fusion proteins are parted in three classes and the subcellular localization of fusion might vary, these proteins have to act, in common, on lipid assemblies. Lipids contribute to fusion through their physical, mechanical and/or chemical properties. Lipids can thus play a role as chemically defined entities, or through their preferential partitioning into membrane microdomains called "rafts", or by modulating the curvature of the membranes involved in the fusion process. The purpose of this review is to make a state of the art on recent findings on the contribution of cholesterol, sphingolipids and glycolipids in cell entry and membrane fusion of a number of viral families, whose members bear either class I or class II fusion proteins, or fusion proteins of the recently discovered third class.

  12. Arabidopsis D6PK is a lipid domain-dependent mediator of root epidermal planar polarity.

    PubMed

    Stanislas, Thomas; Hüser, Anke; Barbosa, Inês C R; Kiefer, Christian S; Brackmann, Klaus; Pietra, Stefano; Gustavsson, Anna; Zourelidou, Melina; Schwechheimer, Claus; Grebe, Markus

    2015-11-02

    Development of diverse multicellular organisms relies on coordination of single-cell polarities within the plane of the tissue layer (planar polarity). Cell polarity often involves plasma membrane heterogeneity generated by accumulation of specific lipids and proteins into membrane subdomains. Coordinated hair positioning along Arabidopsis root epidermal cells provides a planar polarity model in plants, but knowledge about the functions of proteo-lipid domains in planar polarity signalling remains limited. Here we show that Rho-of-plant (ROP) 2 and 6, phosphatidylinositol-4-phosphate 5-kinase 3 (PIP5K3), DYNAMIN-RELATED PROTEIN (DRP) 1A and DRP2B accumulate in a sterol-enriched, polar membrane domain during root hair initiation. DRP1A, DRP2B, PIP5K3 and sterols are required for planar polarity and the AGCVIII kinase D6 PROTEIN KINASE (D6PK) is a modulator of this process. D6PK undergoes phosphatidylinositol-4,5-bisphosphate- and sterol-dependent basal-to-planar polarity switching into the polar, lipid-enriched domain just before hair formation, unravelling lipid-dependent D6PK localization during late planar polarity signalling.

  13. Relative and absolute reliability of measures of linoleic acid-derived oxylipins in human plasma.

    PubMed

    Gouveia-Figueira, Sandra; Bosson, Jenny A; Unosson, Jon; Behndig, Annelie F; Nording, Malin L; Fowler, Christopher J

    2015-09-01

    Modern analytical techniques allow for the measurement of oxylipins derived from linoleic acid in biological samples. Most validatory work has concerned extraction techniques, repeated analysis of aliquots from the same biological sample, and the influence of external factors such as diet and heparin treatment upon their levels, whereas less is known about the relative and absolute reliability of measurements undertaken on different days. A cohort of nineteen healthy males were used, where samples were taken at the same time of day on two occasions, at least 7 days apart. Relative reliability was assessed using Lin's concordance correlation coefficients (CCC) and intraclass correlation coefficients (ICC). Absolute reliability was assessed by Bland-Altman analyses. Nine linoleic acid oxylipins were investigated. ICC and CCC values ranged from acceptable (0.56 [13-HODE]) to poor (near zero [9(10)- and 12(13)-EpOME]). Bland-Altman limits of agreement were in general quite wide, ranging from ±0.5 (12,13-DiHOME) to ±2 (9(10)-EpOME; log10 scale). It is concluded that relative reliability of linoleic acid-derived oxylipins varies between lipids with compounds such as the HODEs showing better relative reliability than compounds such as the EpOMEs. These differences should be kept in mind when designing and interpreting experiments correlating plasma levels of these lipids with factors such as age, body mass index, rating scales etc.

  14. Involvement of lipid peroxidation-derived aldehyde-protein adducts in autoimmunity mediated by trichloroethene.

    PubMed

    Wang, Gangduo; Ansari, G A S; Khan, M Firoze

    2007-12-01

    Lipid peroxidation, a major contributor to cellular damage, is also implicated in the pathogenesis of autoimmune diseases (AD). The focus of this study was to elucidate the role of lipid peroxidation-derived aldehydes in autoimmunity induced and/or exacerbated by chemical exposure. Previous studies showed that trichloroethene (TCE) is capable of inducing/accelerating autoimmunity. To test whether TCE-induced lipid peroxidation might be involved in the induction/exacerbation of autoimmune responses, groups of autoimmune-prone female MRL +/+ mice were treated with TCE (10 mmol/kg, i.p., every 4th day) for 6 or 12 wk. Significant increases of the formation of malondialdehyde (MDA)- and 4-hydroxynonenal (HNE)-protein adducts were found in the livers of TCE-treated mice at both 6 and 12 wk, but the response was greater at 12 wk. Further characterization of these adducts in liver microsomes showed increased formation of MDA-protein adducts with molecular masses of 86, 65, 56, 44, and 32 kD, and of HNE-protein adducts with molecular masses of 87, 79, 46, and 17 kD in TCE-treated mice. In addition, significant induction of anti-MDA- and anti-HNE-protein adduct-specific antibodies was observed in the sera of TCE-treated mice, and showed a pattern similar to MDA- or HNE-protein adducts. The increases in anti-MDA- and anti-HNE-protein adduct antibodies were associated with significant elevation in serum anti-nuclear-, anti-ssDNA- and anti-dsDNA-antibodies at 6 wk and, to a greater extent, at 12 wk. These studies suggest that TCE-induced lipid peroxidation is associated with induction/exacerbation of autoimmune response in MRL+/+ mice, and thus may play an important role in disease pathogenesis. Further interventional studies are needed to establish a causal relationship between lipid peroxidation and TCE-induced autoimmune response.

  15. Nitrogen Substituent Polarity Influences Dithiocarbamate-Mediated Lipid Oxidation, Nerve Copper Accumulation, and Myelin Injury

    PubMed Central

    Valentine, Holly L.; Viquez, Olga M.; Amarnath, Kalyani; Amarnath, Venkataraman; Zyskowski, Justin; Kassa, Endalkachew N.; Valentine, William M.

    2009-01-01

    Dithiocarbamates have a wide spectrum of applications in industry, agriculture, and medicine, with new applications being investigated. Past studies have suggested that the neurotoxicity of some dithiocarbamates may result from copper accumulation, protein oxidative damage, and lipid oxidation. The polarity of a dithiocarbamate’s nitrogen substituents influences the lipophilicity of the copper complexes it generates and thus potentially determines its ability to promote copper accumulation within nerve and induce myelin injury. In the current study, a series of dithiocarbamate-copper complexes differing in their lipophilicity were evaluated for their relative abilities to promote lipid peroxidation determined by malondialdehyde levels generated in an ethyl arachidonate oil-in-water emulsion. In a second component of this study, rats were exposed to either N,N-diethyldithiocarbamate or sarcosine dithiocarbamate; both generate dithiocarbamate-copper complexes that are lipid and water soluble, respectively. Following the exposures, brain, tibial nerve, spinal cord and liver tissue copper levels were measured by inductively coupled mass spectroscopy to assess the relative abilities of these two dithiocarbamates to promote copper accumulation. Peripheral nerve injury was evaluated using grip strengths, nerve conduction velocities and morphologic changes at the light microscope level. Additionally, the protein expression levels of glutathione transferase alpha and heme-oxygenase-1 in nerve were determined and the quantity of protein carbonyls measured to assess levels of oxidative stress and injury. The data provide evidence that dithiocarbamate-copper complexes are redox active; and that the ability of dithiocarbamate complexes to promote lipid peroxidation is correlated to the lipophilicity of the complex. Consistent with neurotoxicity requiring the formation of a lipid soluble copper complex, significant increases in copper accumulation, oxidative stress and myelin

  16. Nitrogen substituent polarity influences dithiocarbamate-mediated lipid oxidation, nerve copper accumulation, and myelin injury.

    PubMed

    Valentine, Holly L; Viquez, Olga M; Amarnath, Kalyani; Amarnath, Venkataraman; Zyskowski, Justin; Kassa, Endalkachew N; Valentine, William M

    2009-01-01

    Dithiocarbamates have a wide spectrum of applications in industry, agriculture, and medicine, with new applications being investigated. Past studies have suggested that the neurotoxicity of some dithiocarbamates may result from copper accumulation, protein oxidative damage, and lipid oxidation. The polarity of a dithiocarbamate's nitrogen substituents influences the lipophilicity of the copper complexes that it generates and thus potentially determines its ability to promote copper accumulation within nerve and induce myelin injury. In the current study, a series of dithiocarbamate-copper complexes differing in their lipophilicity were evaluated for their relative abilities to promote lipid peroxidation determined by malondialdehyde levels generated in an ethyl arachidonate oil-in-water emulsion. In a second component of this study, rats were exposed to either N,N-diethyldithiocarbamate or sarcosine dithiocarbamate; both generated dithiocarbamate-copper complexes that were lipid- and water-soluble, respectively. Following the exposures, brain, tibial nerve, spinal cord, and liver tissue copper levels were measured by inductively coupled mass spectroscopy to assess the relative abilities of these two dithiocarbamates to promote copper accumulation. Peripheral nerve injury was evaluated using grip strengths, nerve conduction velocities, and morphologic changes at the light microscope level. Additionally, the protein expression levels of glutathione transferase alpha and heme-oxygenase-1 in nerve were determined, and the quantity of protein carbonyls was measured to assess levels of oxidative stress and injury. The data provided evidence that dithiocarbamate-copper complexes are redox active and that the ability of dithiocarbamate complexes to promote lipid peroxidation is correlated to the lipophilicity of the complex. Consistent with neurotoxicity requiring the formation of a lipid-soluble copper complex, significant increases in copper accumulation, oxidative

  17. Alterations in lipid mediated signaling and Wnt/ β -catenin signaling in DMH induced colon cancer on supplementation of fish oil.

    PubMed

    Kansal, Shevali; Vaiphei, Kim; Agnihotri, Navneet

    2014-01-01

    Ceramide mediates inhibition of cyclooxygenase-2 (COX-2) which catalyzes formation of prostaglandin further activating peroxisome proliferator-activated receptor γ (PPAR γ ) and Wnt/ β -catenin pathway; and hence plays a critical role in cancer. Therefore, in current study, ceramide, COX-2, 15-deoxy prostaglandin J2(15-deoxy PGJ2), PPAR γ , and β -catenin were estimated to evaluate the effect of fish oil on lipid mediated and Wnt/ β -catenin signaling in colon carcinoma. Male Wistar rats in Group I received purified diet while Groups II and III received modified diet supplemented with FO : CO(1 : 1) and FO : CO(2.5 : 1), respectively. These were further subdivided into controls receiving ethylenediaminetetraacetic acid and treated groups receiving dimethylhydrazine dihydrochloride (DMH)/week for 4 weeks. Animals sacrificed 48 hours after last injection constituted initiation phase and those sacrificed after 16 weeks constituted postinitiation phase. Decreased ceramide and increased PPAR γ were observed in postinitiation phase only. On receiving FO+CO(1 : 1)+DMH and FO+CO(2.5 : 1)+DMH in both phases, ceramide was augmented whereas COX-2, 15-deoxy PGJ2, and nuclear translocation of β -catenin were reduced with respect to cancerous animals. Decrease was more significant in postinitiation phase with FO+CO(2.5 : 1)+DMH. Treatment with oils increased PPAR γ in initiation phase but decreased it in postinitiation phase. Hence, fish oil altered lipid mediated signalling in a dose and time dependent manner so as to inhibit progression of colon cancer.

  18. Microbial production of fatty acid-derived fuels and chemicals

    PubMed Central

    Lennen, Rebecca M; Pfleger, Brian F

    2013-01-01

    Fatty acid metabolism is an attractive route to produce liquid transportation fuels and commodity oleochemicals from renewable feedstocks. Recently, genes and enzymes, which comprise metabolic pathways for producing fatty acid-derived compounds (e.g. esters, alkanes, olefins, ketones, alcohols, polyesters) have been elucidated and used in engineered microbial hosts. The resulting strains often generate products at low percentages of maximum theoretical yields, leaving significant room for metabolic engineering. Economically viable processes will require strains to approach theoretical yields, particularly for replacement of petroleum-derived fuels. This review will describe recent progress toward this goal, highlighting the scientific discoveries of each pathway, ongoing biochemical studies to understand each enzyme, and metabolic engineering strategies that are being used to improve strain performance. PMID:23541503

  19. Anti-inflammatory effects of hydroxycinnamic acid derivatives

    SciTech Connect

    Nagasaka, Reiko; Chotimarkorn, Chatchawan; Shafiqul, Islam Md.; Hori, Masatoshi; Ozaki, Hiroshi; Ushio, Hideki . E-mail: hushio@kaiyodai.ac.jp

    2007-06-29

    NF-{kappa}B family of transcription factors are involved in numerous cellular processes, including differentiation, proliferation, and inflammation. It was reported that hydroxycinnamic acid derivatives (HADs) are inhibitors of NF-{kappa}B activation. Rice bran oil contains a lot of phytosteryl ferulates, one of HADs. We have investigated effects of phytosteryl ferulates on NF-{kappa}B activation in macrophage. Cycloartenyl ferulate (CAF), one of phytosteryl ferulates, significantly reduced lipopolysaccharide (LPS)-induced NO production and mRNA expression of inducible NO synthase and cyclooxygenese-2 but upregulated SOD activity. Electrophoresis mobility shift assay revealed that CAF inhibited DNA-binding of NF-{kappa}B. CAF and phytosteryl ferulates probably have potentially anti-inflammatory properties.

  20. [Acute kidney failure during psoriasis therapy with fumaric acid derivatives].

    PubMed

    Dalhoff, K; Faerber, P; Arnholdt, H; Sack, K; Strubelt, O

    1990-06-29

    24 days after starting treatment of psoriasis with fumaric acid derivatives (0.8-1.0 g orally, plus unknown quantities locally) a 21-year-old woman developed acute oliguric renal failure with a rise of serum creatinine levels to 1094 mumol/l (12.4 mg/dl). Deterioration of renal function had been preceded by severe abdominal symptoms with nausea, vomiting and colicky pain. On admission to hospital she was dehydrated with hyponatraemia and hypokalaemia. There was glomerular microhaematuria, increased excretion of renal epithelia, and tubular proteinuria. Renal biopsy demonstrated acute tubular damage with vacuolization of proximal epithelia, dilated tubules and scattered necroses. After intermittent haemodialysis (13 courses over two weeks) renal function gradually recovered, as demonstrated at a follow-up examination four months after discharge.

  1. Membrane extraction with thermodynamically unstable diphosphonic acid derivatives

    DOEpatents

    Horwitz, Earl Philip; Gatrone, Ralph Carl; Nash, Kenneth LaVerne

    1997-01-01

    Thermodynamically-unstable complexing agents which are diphosphonic acids and diphosphonic acid derivatives (or sulphur containing analogs), like carboxyhydroxymethanediphosphonic acid and vinylidene-1,1-diphosphonic acid, are capable of complexing with metal ions, and especially metal ions in the II, III, IV, V and VI oxidation states, to form stable, water-soluble metal ion complexes in moderately alkaline to highly-acidic media. However, the complexing agents can be decomposed, under mild conditions, into non-organic compounds which, for many purposes are environmentally-nondamaging compounds thereby degrading the complex and releasing the metal ion for disposal or recovery. Uses for such complexing agents as well as methods for their manufacture are also described.

  2. Membrane extraction with thermodynamically unstable diphosphonic acid derivatives

    DOEpatents

    Horwitz, E.P.; Gatrone, R.C.; Nash, K.L.

    1997-10-14

    Thermodynamically-unstable complexing agents which are diphosphonic acids and diphosphonic acid derivatives (or sulphur containing analogs), like carboxyhydroxymethanediphosphonic acid and vinylidene-1,1-diphosphonic acid, are capable of complexing with metal ions, and especially metal ions in the II, III, IV, V and VI oxidation states, to form stable, water-soluble metal ion complexes in moderately alkaline to highly-acidic media. However, the complexing agents can be decomposed, under mild conditions, into non-organic compounds which, for many purposes are environmentally-nondamaging compounds thereby degrading the complex and releasing the metal ion for disposal or recovery. Uses for such complexing agents as well as methods for their manufacture are also described. 1 fig.

  3. Frustrated smectic liquid crystalline phases in lactic acid derivatives

    NASA Astrophysics Data System (ADS)

    Glogarová, M.; Novotná, V.

    2016-08-01

    We have prepared and studied a series of compounds with different types of molecular core and lactate unit in the chiral terminal chain. We draw a survey and comparison of their mesomorphic properties with respect to the occurrence of twist grain boundary (TGB) phases. The materials exhibit extremely wide TGBA phase more than 60K broad, unique TGBA-TGBC-SmC*-SmCA* phase sequence and unique re-entrant TGBA phase below the SmA phase. TGB phases have been induced in binary mixtures of molecules with different molecular shape and chirality (chiral lactic acid derivative and non-chiral hockey-stick mesogen). Unique effect is observed for compounds with TGBA phase, where the applied electric field transforms the planar texture into the homeotropic one, homogeneously dark in crossed polarizers. The process is analogy of the Frederiks transition so far known only for nematics. This effect, changing the bright state to the dark one, is promising for applications.

  4. Vanadium-mediated lipid peroxidation in microsomes from human term placenta

    SciTech Connect

    Byczkowski, J.Z.; Wan, B.; Kulkarni, A.P.

    1988-11-01

    Vanadium is considered an essential element present in living organisms in trace amounts but it is toxic when introduced in excessive doses to animals and humans. Vanadium compounds are extensively used in modern industry and occupational exposure to high doses of vanadium is quite common. In pregnant mice, vanadium accumulates preferentially in the placenta and to lower extent in fetal skeleton and mammary gland during exposure to radioactive vanadium. Accumulation of vanadium in fetoplacental unit may present threat to the fetus by interacting with enzymes and ion-transporting systems in membranes. It is also possible that accumulation of vanadium with its concomitant reduction to vanadyl may lead to lipid peroxidation, followed by damage to biological membranes, lysosomal enzymes release and destruction of placental tissue. To explore some of these possibilities the authors decided to examine whether vanadate can undergo redox cycling in microsomes from human term placenta (HTP) that can lead to lipid peroxidation.

  5. Effects of Surface Ligand Density on Lipid-Monolayer-mediated 2D Assembly of Proteins

    SciTech Connect

    Fukuto, M.; Wang, S; Lohr, M; Kewalramani, S; Yang, L

    2010-01-01

    The two-dimensional (2D) assembly of the protein streptavidin on a biotin-bearing lipid monolayer was studied as a function of the surface density of biotin, a protein-binding ligand, by means of in situ X-ray scattering and optical Brewster angle microscopy measurements at the liquid-vapor interface. Although this model system has been studied extensively, the relationship between the surface biotin density and the adsorption, 2D phase behavior, and binding state of streptavidin has yet to be determined quantitatively. The observed equilibrium phase behavior provides direct structural evidence that the 2D crystallization of the lipid-bound streptavidin occurs as a density-driven first-order phase transition. The minimum biotin density required for the 2D crystallization of streptavidin is found to be remarkably close to the density of the ligand-binding sites in the protein crystal. Moreover, both above and below this transition, the observed biotin-density dependence of protein adsorption is well described by the binding of biotin-bearing lipids at both of the two available sites per streptavidin molecule. These results imply that even in the low-density noncrystalline phase, the bound proteins share a common, fixed orientation relative to the surface normal, and that the 2D crystallization occurs when the lateral protein density reaches 50-70% of the 2D crystal density. This study demonstrates that in addition to a well-defined molecular orientation, high lateral packing density is essential to the 2D crystallization of proteins.

  6. Hypericin-mediated sonodynamic therapy induces autophagy and decreases lipids in THP-1 macrophage by promoting ROS-dependent nuclear translocation of TFEB

    PubMed Central

    Li, Xuesong; Zhang, Xin; Zheng, Longbin; Kou, Jiayuan; Zhong, Zhaoyu; Jiang, Yueqing; Wang, Wei; Dong, Zengxiang; Liu, Zhongni; Han, Xiaobo; Li, Jing; Tian, Ye; Zhao, Yajun; Yang, Liming

    2016-01-01

    Lipid catabolism disorder is the primary cause of atherosclerosis. Transcription factor EB (TFEB) prevents atherosclerosis by activating macrophage autophagy to promote lipid degradation. Hypericin-mediated sonodynamic therapy (HY-SDT) has been proved non-invasively inducing THP-1-derived macrophage apoptosis; however, it is unknown whether macrophage autophagy could be triggered by HY-SDT to influence cellular lipid catabolism via regulating TFEB. Here, we report that HY-SDT resulted in the time-dependent THP-1-derived macrophage autophagy activation through AMPK/AKT/mTOR pathway. Besides, TFEB nuclear translocation in macrophage was triggered by HY-SDT to promote autophagy activation and lysosome regeneration which enhanced lipid degradation in response to atherogenic lipid stressors. Moreover, following HY-SDT, the ABCA1 expression level was increased to promote lipid efflux in macrophage, and the expression levels of CD36 and SR-A were decreased to inhibit lipid uptake, both of which were prevented by TFEB knockdown. These results indicated that TFEB nuclear translocation activated by HY-SDT was not only the key regulator of autophagy activation and lysosome regeneration in macrophage to promote lipolysis, but also had a crucial role in reverse cholesterol transporters to decrease lipid uptake and increase lipid efflux. Reactive oxygen species (ROS) were adequately generated in macrophage by HY-SDT. Further, ROS scavenger N-acetyl-l-cysteine abolished HY-SDT-induced TFEB nuclear translocation and autophagy activation, implying that ROS were the primary upstream factors responsible for these effects during HY-SDT. In summary, our data indicate that HY-SDT decreases lipid content in macrophage by promoting ROS-dependent nuclear translocation of TFEB to influence consequent autophagy activation and cholesterol transporters. Thus, HY-SDT may be beneficial for atherosclerosis via TFEB regulation to ameliorate lipid overload in atherosclerotic plaques. PMID:28005078

  7. Iron-Ascorbate-Mediated Lipid Peroxidation Causes Epigenetic Changes in the Antioxidant Defense in Intestinal Epithelial Cells: Impact on Inflammation

    PubMed Central

    Yara, Sabrina; Lavoie, Jean-Claude; Beaulieu, Jean-François; Delvin, Edgard; Amre, Devendra; Marcil, Valerie; Seidman, Ernest; Levy, Emile

    2013-01-01

    Introduction The gastrointestinal tract is frequently exposed to noxious stimuli that may cause oxidative stress, inflammation and injury. Intraluminal pro-oxidants from ingested nutrients especially iron salts and ascorbic acid frequently consumed together, can lead to catalytic formation of oxygen-derived free radicals that ultimately overwhelm the cellular antioxidant defense and lead to cell damage. Hypothesis Since the mechanisms remain sketchy, efforts have been exerted to evaluate the role of epigenetics in modulating components of endogenous enzymatic antioxidants in the intestine. To this end, Caco-2/15 cells were exposed to the iron-ascorbate oxygen radical-generating system. Results Fe/Asc induced a significant increase in lipid peroxidation as reflected by the elevated formation of malondialdehyde along with the alteration of antioxidant defense as evidenced by raised superoxide dismutase 2 (SOD2) and diminished glutathione peroxidase (GPx) activities and genes. Consequently, there was an up-regulation of inflammatory processes illustrated by the activation of NF-κB transcription factor, the higher production of interleukin-6 and cycloxygenase-2 as well as the decrease of IκB. Assessment of promoter’s methylation revealed decreased levels for SOD2 and increased degree for GPx2. On the other hand, pre-incubation of Caco-2/15 cells with 5-Aza-2′-deoxycytidine, a demethylating agent, or Trolox antioxidant normalized the activities of SOD2 and GPx, reduced lipid peroxidation and prevented inflammation. Conclusion Redox and inflammatory modifications in response to Fe/Asc -mediated lipid peroxidation may implicate epigenetic methylation. PMID:23717425

  8. Resolving inflammation: dual anti-inflammatory and pro-resolution lipid mediators

    PubMed Central

    Serhan, Charles N.; Chiang, Nan; Van Dyke, Thomas E.

    2009-01-01

    Preface Active resolution of acute inflammation is a previously unrecognized interface between innate and adaptive immunity. Once thought to be a passive process, the resolution of inflammation is now shown to involve active biochemical programmes that enable inflamed tissues to return to homeostasis. This Review presents newly uncovered cellular and molecular mechanisms for the resolution of inflammation, revealing key roles for eicosanoids, such as lipoxins, and new families of endogenous chemical mediators, termed resolvins and protectins. These mediators carry antiinflammatory and pro-resolution properties with leukocytes, protect organs and stimulate mucosal antimicrobial defence and clearance. Together, they control local inflammatory responses at multiple levels to stimulate resolution. PMID:18437155

  9. Revealing the mechanism of passive transport in lipid bilayers via phonon-mediated nanometre-scale density fluctuations

    DOE PAGES

    Zhernenkov, Mikhail; Bolmatov, Dima; Soloviov, Dmitry; ...

    2016-05-12

    We report the high resolution inelastic x-ray study of the in-plane phonon excitations in dipalmitoyl phosphatidylcholine (DPPC) above and below main transition temperature. In the Lβ' gel phase, we observe high frequency longitudinal phonon mode previously predicted by the molecular dynamics simulations and for the first time, we reveal low frequency weakly dispersive transverse acoustic mode which softens and exhibits a low-frequency phonon gap when the DPPC lipid transitions into the Lα fluid phase. The phonon softening of the high frequency longitudinal excitations and the transformation of the transverse excitations upon the phase transition from the Lβ' to Lα phasemore » is explained within the framework of the phonon theory of liquids. These findings illustrate the importance of the collective dynamics of biomembranes and reveal that hydrocarbon tails can act as an efficient mediator in controlling the passive transport across the bilayer plane.« less

  10. Receptor-mediated membrane adhesion of lipid-polymer hybrid (LPH) nanoparticles studied by dissipative particle dynamics simulations.

    PubMed

    Li, Zhenlong; Gorfe, Alemayehu A

    2015-01-14

    Lipid-polymer hybrid (LPH) nanoparticles represent a novel class of targeted drug delivery platforms that combine the advantages of liposomes and biodegradable polymeric nanoparticles. However, the molecular details of the interaction between LPHs and their target cell membranes remain poorly understood. We have investigated the receptor-mediated membrane adhesion process of a ligand-tethered LPH nanoparticle using extensive dissipative particle dynamics (DPD) simulations. We found that the spontaneous adhesion process follows a first-order kinetics characterized by two distinct stages: a rapid nanoparticle-membrane engagement, followed by a slow growth in the number of ligand-receptor pairs coupled with structural re-organization of both the nanoparticle and the membrane. The number of ligand-receptor pairs increases with the dynamic segregation of ligands and receptors toward the adhesion zone causing an out-of-plane deformation of the membrane. Moreover, the fluidity of the lipid shell allows for strong nanoparticle-membrane interactions to occur even when the ligand density is low. The LPH-membrane avidity is enhanced by the increased stability of each receptor-ligand pair due to the geometric confinement and the cooperative effect arising from multiple binding events. Thus, our results reveal the unique advantages of LPH nanoparticles as active cell-targeting nanocarriers and provide some general principles governing nanoparticle-cell interactions that may aid future design of LPHs with improved affinity and specificity for a given target of interest.

  11. Transferrin-PEG-PE modified dexamethasone conjugated cationic lipid carrier mediated gene delivery system for tumor-targeted transfection

    PubMed Central

    Wang, Wei; Zhou, Fang; Ge, Linfu; Liu, Ximin; Kong, Fansheng

    2012-01-01

    Background The main barriers to non-viral gene delivery include cellular and nuclear membranes. As such, the aim of this study was to develop a type of vector that can target cells through receptor-mediated pathways and by using nuclear localization signal (NLS) to increase the nuclear uptake of genetic materials. Methods A dexamethasone (Dexa)-conjugated lipid was synthesized as the material of the solid lipid nanoparticles (SLNs), and transferrin (Tf) was linked onto polyethylene glycol-phosphatidylethanolamine (PEG-PE) to obtain Tf-PEG-PE ligands for the surface modification of the carriers. The in vitro transfection efficiency of the novel modified vectors was evaluated in human hepatoma carcinoma cell lines, and in vivo effects were observed in an animal model. Results Tf-PEG-PE modified SLNs/enhanced green fluorescence protein plasmid (pEGFP) had a particle size of 222 nm and a gene loading quantity of 90%. Tf-PEG-PE-modified SLNs/pEGFP (Tf-SLNs/pEGFP) displayed remarkably higher transfection efficiency than non-modified SLNs/pEGFP and the vectors not containing Dexa, both in vitro and in vivo. Conclusion It can be concluded that Tf and Dexa could function as an excellent active targeting ligand to improve the cell targeting and nuclear targeting ability of the carriers, and the resulting nanomedicine could be a promising active targeting drug/gene delivery system. PMID:22679364

  12. Lipid solvation effects contribute to the affinity of Gly-xxx-Gly motif-mediated helix-helix interactions.

    PubMed

    Johnson, Rachel M; Rath, Arianna; Melnyk, Roman A; Deber, Charles M

    2006-07-18

    Interactions between transmembrane helices are mediated by the concave Gly-xxx-Gly motif surface. Whether Gly residues per se are sufficient for selection of this motif has not been established. Here, we used the in vivo TOXCAT assay to measure the relative affinities of all 18 combinations of Gly, Ala, and Ser "small-xxx-small" mutations in glycophorin A (GpA) and bacteriophage M13 major coat protein (MCP) homodimers. Affinity values were compared with the accessibility to a methylene-sized probe of the total surface area of each helix monomer as a measure of solvation by membrane components. A strong inverse correlation was found between nonpolar-group lipid accessibility and dimer affinity (R = 0.75 for GpA, p = 0.013, and R = 0.81 for MCP, p = 0.004), suggesting that lipid as a poor membrane protein solvent, conceptually analogous to water in soluble protein folding, can contribute to dimer stability and help to define helix-helix interfaces.

  13. Rab14 specifies the apical membrane through Arf6-mediated regulation of lipid domains and Cdc42

    PubMed Central

    Lu, Ruifeng; Wilson, Jean M.

    2016-01-01

    The generation of cell polarity is essential for the development of multi-cellular organisms as well as for the function of epithelial organs in the mature animal. Small GTPases regulate the establishment and maintenance of polarity through effects on cytoskeleton, membrane trafficking, and signaling. Using short-term 3-dimensional culture of MDCK cells, we find that the small GTPase Rab14 is required for apical membrane specification. Rab14 knockdown results in disruption of polarized lipid domains and failure of the Par/aPKC/Cdc42 polarity complex to localize to the apical membrane. These effects are mediated through tight control of lipid localization, as overexpression of the phosphatidylinositol 4-phosphate 5-kinase α [PtdIns(4)P5K] activator Arf6 or PtdIns(4)P5K alone, or treatment with the phosphatidylinositol 3-kinase (PtdInsI3K) inhibitor wortmannin, rescued the multiple-apical domain phenotype observed after Rab14 knockdown. Rab14 also co-immunoprecipitates and colocalizes with the small GTPase Cdc42, and Rab14 knockdown results in increased Cdc42 activity. Furthermore, Rab14 regulates trafficking of vesicles to the apical domain, mitotic spindle orientation, and midbody position, consistent with Rab14’s reported localization to the midbody as well as its effects upon Cdc42. These results position Rab14 at the top of a molecular cascade that regulates the establishment of cell polarity. PMID:27901125

  14. Autotaxin-mediated lipid signaling intersects with LIF and BMP signaling to promote the naive pluripotency transcription factor program

    PubMed Central

    Kime, Cody; Sakaki-Yumoto, Masayo; Goodrich, Leeanne; Hayashi, Yohei; Sami, Salma; Derynck, Rik; Asahi, Michio; Panning, Barbara; Yamanaka, Shinya; Tomoda, Kiichiro

    2016-01-01

    Developmental signaling molecules are used for cell fate determination, and understanding how their combinatorial effects produce the variety of cell types in multicellular organisms is a key problem in biology. Here, we demonstrate that the combination of leukemia inhibitory factor (LIF), bone morphogenetic protein 4 (BMP4), lysophosphatidic acid (LPA), and ascorbic acid (AA) efficiently converts mouse primed pluripotent stem cells (PSCs) into naive PSCs. Signaling by the lipid LPA through its receptor LPAR1 and downstream effector Rho-associated protein kinase (ROCK) cooperated with LIF signaling to promote this conversion. BMP4, which also stimulates conversion to naive pluripotency, bypassed the need for exogenous LPA by increasing the activity of the extracellular LPA-producing enzyme autotaxin (ATX). We found that LIF and LPA-LPAR1 signaling affect the abundance of signal transducer and activator of transcription 3 (STAT3), which induces a previously unappreciated Kruppel-like factor (KLF)2-KLF4-PR domain 14 (PRDM14) transcription factor circuit key to establish naive pluripotency. AA also affects this transcription factor circuit by controlling PRDM14 expression. Thus, our study reveals that ATX-mediated autocrine lipid signaling promotes naive pluripotency by intersecting with LIF and BMP4 signaling. PMID:27738243

  15. Pro-resolving lipid mediator Resolvin D1 serves as a marker of lung disease in cystic fibrosis

    PubMed Central

    Fussbroich, Daniela; Mueller, Klaus; Serve, Friederike; Smaczny, Christina; Zielen, Stefan; Schubert, Ralf

    2017-01-01

    Background Cystic fibrosis (CF) is an autosomal recessive genetic disorder that affects multiple organs, including the lungs, pancreas, liver and intestine. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) locus lead to defective proteins and reduced Cl- secretion and Na+ hyperabsorption in the affected organs. In addition, patients suffering from CF display chronic inflammation that contributes to the pathogenesis of CF. Recent work suggests that CF patients have a reduced capacity to biosynthesize specialized pro-resolving lipid mediators (SPMs), which contributes to the development and duration of the unwanted inflammation. Alterations in the metabolism of arachidonic acid (AA) and docosahexaenoic acid (DHA) to specialized pro-resolving mediators (SPMs), like lipoxins (LXs), maresins (MaRs), protectins (PDs) and resolvins (Rvs), may play a major role on clinical impact of airway inflammation in CF. Methods In this study, our aims were to detect and quantitate Resolvin D1 (RvD1) in sputum and plasma from patients with CF and compare levels of RvD1 with biomarkers of inflammation and lung function. We studied 27 CF patients aged 6 to 55 years (median 16 years) in a prospective approach. Results DHA can be found in the plasma of our CF patients in the milligram range and is decreased in comparison to a healthy control group. The DHA-derived pro-resolving mediator Resolvin D1 (RvD1) was also present in the plasma (286.4 ± 50 pg/ mL, mean ± SEM) and sputum (30.0 ± 2.6 pg/ mL, mean ± SEM) samples from our patients with CF and showed a positive correlation with sputum inflammatory markers. The plasma concentrations of RvD1 were ten times higher than sputum concentrations. Interestingly, sputum RvD1/ IL-8 levels showed a positive correlation with FEV1 (rs = 0.3962, p< 0.05). Conclusions SPMs, like RvD1, are well known to down-regulate inflammatory pathways. Our study shows that the bioactive lipid mediator RvD1, derived from DHA, was

  16. Group X Phospholipase A2 Stimulates the Proliferation of Colon Cancer Cells by Producing Various Lipid Mediators

    PubMed Central

    Surrel, Fanny; Jemel, Ikram; Boilard, Eric; Bollinger, James G.; Payré, Christine; Mounier, Carine M.; Talvinen, Kati A.; Laine, Veli J. O.; Nevalainen, Timo J.; Gelb, Michael H.

    2009-01-01

    Among mammalian secreted phospholipases A2 (sPLA2s), the group X enzyme has the most potent hydrolyzing capacity toward phosphatidylcholine, the major phospholipid of cell membrane and lipoproteins. This enzyme has recently been implicated in chronic inflammatory diseases such as atherosclerosis and asthma and may also play a role in colon tumorigenesis. We show here that group X sPLA2 [mouse (m)GX] is one of the most highly expressed PLA2 in the mouse colon and that recombinant mouse and human enzymes stimulate proliferation and mitogen-activated protein kinase activation of various colon cell lines, including Colon-26 cancer cells. Among various recombinant sPLA2s, mGX is the most potent enzyme to stimulate cell proliferation. Based on the use of sPLA2 inhibitors, catalytic site mutants, and small interfering RNA silencing of cytosolic PLA2α and M-type sPLA2 receptor, we demonstrate that mGX promotes cell proliferation independently of the receptor and via its intrinsic catalytic activity and production of free arachidonic acid and lysophospholipids, which are mitogenic by themselves. mGX can also elicit the production of large amounts of prostaglandin E2 and other eicosanoids from Colon-26 cells, but these lipid mediators do not play a role in mGX-induced cell proliferation because inhibitors of cyclooxygenases and lipoxygenases do not prevent sPLA2 mitogenic effects. Together, our results indicate that group X sPLA2 may play an important role in colon tumorigenesis by promoting cancer cell proliferation and releasing various lipid mediators involved in other key events in cancer progression. PMID:19602573

  17. Group X phospholipase A2 stimulates the proliferation of colon cancer cells by producing various lipid mediators.

    PubMed

    Surrel, Fanny; Jemel, Ikram; Boilard, Eric; Bollinger, James G; Payré, Christine; Mounier, Carine M; Talvinen, Kati A; Laine, Veli J O; Nevalainen, Timo J; Gelb, Michael H; Lambeau, Gérard

    2009-10-01

    Among mammalian secreted phospholipases A2 (sPLA(2)s), the group X enzyme has the most potent hydrolyzing capacity toward phosphatidylcholine, the major phospholipid of cell membrane and lipoproteins. This enzyme has recently been implicated in chronic inflammatory diseases such as atherosclerosis and asthma and may also play a role in colon tumorigenesis. We show here that group X sPLA(2) [mouse (m)GX] is one of the most highly expressed PLA(2) in the mouse colon and that recombinant mouse and human enzymes stimulate proliferation and mitogen-activated protein kinase activation of various colon cell lines, including Colon-26 cancer cells. Among various recombinant sPLA(2)s, mGX is the most potent enzyme to stimulate cell proliferation. Based on the use of sPLA(2) inhibitors, catalytic site mutants, and small interfering RNA silencing of cytosolic PLA(2)alpha and M-type sPLA(2) receptor, we demonstrate that mGX promotes cell proliferation independently of the receptor and via its intrinsic catalytic activity and production of free arachidonic acid and lysophospholipids, which are mitogenic by themselves. mGX can also elicit the production of large amounts of prostaglandin E2 and other eicosanoids from Colon-26 cells, but these lipid mediators do not play a role in mGX-induced cell proliferation because inhibitors of cyclooxygenases and lipoxygenases do not prevent sPLA(2) mitogenic effects. Together, our results indicate that group X sPLA(2) may play an important role in colon tumorigenesis by promoting cancer cell proliferation and releasing various lipid mediators involved in other key events in cancer progression.

  18. Resveratrol-mediated autophagy requires WIPI-1-regulated LC3 lipidation in the absence of induced phagophore formation.

    PubMed

    Mauthe, Mario; Jacob, Anke; Freiberger, Sandra; Hentschel, Katharina; Stierhof, York-Dieter; Codogno, Patrice; Proikas-Cezanne, Tassula

    2011-12-01

    Canonical autophagy is positively regulated by the Beclin 1/phosphatidylinositol 3-kinase class III (PtdIns3KC3) complex that generates an essential phospholipid, phosphatidylinositol 3-phosphate (PtdIns(3)P), for the formation of autophagosomes. Previously, we identified the human WIPI protein family and found that WIPI-1 specifically binds PtdIns(3)P, accumulates at the phagophore and becomes a membrane protein of generated autophagosomes. Combining siRNA-mediated protein downregulation with automated high through-put analysis of PtdIns(3)P-dependent autophagosomal membrane localization of WIPI-1, we found that WIPI-1 functions upstream of both Atg7 and Atg5, and stimulates an increase of LC3-II upon nutrient starvation. Resveratrol-mediated autophagy was shown to enter autophagic degradation in a noncanonical manner, independent of Beclin 1 but dependent on Atg7 and Atg5. By using electron microscopy, LC3 lipidation and GFP-LC3 puncta-formation assays we confirmed these results and found that this effect is partially wortmannin-insensitive. In line with this, resveratrol did not promote phagophore localization of WIPI-1, WIPI-2 or the Atg16L complex above basal level. In fact, the presence of resveratrol in nutrient-free conditions inhibited phagophore localization of WIPI-1. Nevertheless, we found that resveratrol-mediated autophagy functionally depends on canonical-driven LC3-II production, as shown by siRNA-mediated downregulation of WIPI-1 or WIPI-2. From this it is tempting to speculate that resveratrol promotes noncanonical autophagic degradation downstream of the PtdIns(3)P-WIPI-Atg7-Atg5 pathway, by engaging a distinct subset of LC3-II that might be generated at membrane origins apart from canonical phagophore structures.

  19. Nanoparticle-mediated intracellular lipid accumulation during C2C12 cell differentiation

    SciTech Connect

    Tsukahara, Tamotsu; Haniu, Hisao

    2011-03-25

    Research highlights: {yields} HTT2800 has a significant effect on intracellular lipid accumulation. {yields} HTT2800 reduced muscle-specific genes and led to the emergence of adipocyte-related genes. {yields} HT2800 converts the differentiation pathway of C2C12 myoblasts to that of adipoblast-like cells. -- Abstract: In this report, we sought to elucidate whether multiwall carbon nanotubes are involved in the modulation of the proliferation and differentiation of the skeletal muscle cell line C2C12. Skeletal muscle is a major mass peripheral tissue that accounts for 40% of total body weight and 50% of energy consumption. We focused on the differentiation pathway of myoblasts after exposure to a vapor-grown carbon fiber, HTT2800, which is one of the most highly purified carbon nanotubes. This treatment leads in parallel to the expression of a typical adipose differentiation program. We found that HTT2800 stimulated intracellular lipid accumulation in C2C12 cells. We have also shown by quantified PCR analysis that the expression of adipose-related genes was markedly upregulated during HTT2800 exposure. Taken together, these results suggest that HTT2800 specifically converts the differentiation pathway of C2C12 myoblasts to that of adipoblast-like cells.

  20. Microtubule-Mediated Inositol Lipid Signaling Plays Critical Roles in Regulation of Blebbing.

    PubMed

    Sugiyama, Tatsuroh; Pramanik, Md Kamruzzaman; Yumura, Shigehiko

    2015-01-01

    Cells migrate by extending pseudopods such as lamellipodia and blebs. Although the signals leading to lamellipodia extension have been extensively investigated, those for bleb extension remain unclear. Here, we investigated signals for blebbing in Dictyostelium cells using a newly developed assay to induce blebbing. When cells were cut into two pieces with a microneedle, the anucleate fragments vigorously extended blebs. This assay enabled us to induce blebbing reproducibly, and analyses of knockout mutants and specific inhibitors identified candidate molecules that regulate blebbing. Blebs were also induced in anucleate fragments of leukocytes, indicating that this assay is generally applicable to animal cells. After cutting, microtubules in the anucleate fragments promptly depolymerized, followed by the extension of blebs. Furthermore, when intact cells were treated with a microtubule inhibitor, they frequently extended blebs. The depolymerization of microtubules induced the delocalization of inositol lipid phosphatidylinositol 3,4,5-trisphosphate from the cell membrane. PI3 kinase-null cells frequently extended blebs, whereas PTEN-null cells extended fewer blebs. From these observations, we propose a model in which microtubules play a critical role in bleb regulation via inositol lipid metabolism.

  1. Structural Basis for Ca2+-mediated Interaction of the Perforin C2 Domain with Lipid Membranes*

    PubMed Central

    Yagi, Hiromasa; Conroy, Paul J.; Leung, Eleanor W. W.; Law, Ruby H. P.; Trapani, Joseph A.; Voskoboinik, Ilia; Whisstock, James C.; Norton, Raymond S.

    2015-01-01

    Natural killer cells and cytotoxic T-lymphocytes deploy perforin and granzymes to kill infected host cells. Perforin, secreted by immune cells, binds target membranes to form pores that deliver pro-apoptotic granzymes into the target cell. A crucial first step in this process is interaction of its C2 domain with target cell membranes, which is a calcium-dependent event. Some aspects of this process are understood, but many molecular details remain unclear. To address this, we investigated the mechanism of Ca2+ and lipid binding to the C2 domain by NMR spectroscopy and x-ray crystallography. Calcium titrations, together with dodecylphosphocholine micelle experiments, confirmed that multiple Ca2+ ions bind within the calcium-binding regions, activating perforin with respect to membrane binding. We have also determined the affinities of several of these binding sites and have shown that this interaction causes a significant structural rearrangement in CBR1. Thus, it is proposed that Ca2+ binding at the weakest affinity site triggers changes in the C2 domain that facilitate its interaction with lipid membranes. PMID:26306037

  2. Microtubule-Mediated Inositol Lipid Signaling Plays Critical Roles in Regulation of Blebbing

    PubMed Central

    Sugiyama, Tatsuroh; Pramanik, Md. Kamruzzaman; Yumura, Shigehiko

    2015-01-01

    Cells migrate by extending pseudopods such as lamellipodia and blebs. Although the signals leading to lamellipodia extension have been extensively investigated, those for bleb extension remain unclear. Here, we investigated signals for blebbing in Dictyostelium cells using a newly developed assay to induce blebbing. When cells were cut into two pieces with a microneedle, the anucleate fragments vigorously extended blebs. This assay enabled us to induce blebbing reproducibly, and analyses of knockout mutants and specific inhibitors identified candidate molecules that regulate blebbing. Blebs were also induced in anucleate fragments of leukocytes, indicating that this assay is generally applicable to animal cells. After cutting, microtubules in the anucleate fragments promptly depolymerized, followed by the extension of blebs. Furthermore, when intact cells were treated with a microtubule inhibitor, they frequently extended blebs. The depolymerization of microtubules induced the delocalization of inositol lipid phosphatidylinositol 3,4,5-trisphosphate from the cell membrane. PI3 kinase-null cells frequently extended blebs, whereas PTEN-null cells extended fewer blebs. From these observations, we propose a model in which microtubules play a critical role in bleb regulation via inositol lipid metabolism. PMID:26317626

  3. Tempol protects blood proteins and lipids against peroxynitrite-mediated oxidative damage

    PubMed Central

    Mustafa, Ayman G; Bani-Ahmad, Mohammad A; Jaradat, Ahmad Q

    2015-01-01

    Oxidative stress is characterized by excessive production of various free radicals and reactive species among which, peroxynitrite is most frequently produced in several pathological conditions. Peroxynitrite is the product of the superoxide anion reaction with nitric oxide, which is reported to take place in the intravascular compartment. Several studies have reported that peroxynitrite targets red blood cells, platelets and plasma proteins, and induces various forms of oxidative damage. This in vitro study was designed to further characterize the types of oxidative damage induced in platelets and plasma proteins by peroxynitrite. This study also determined the ability of tempol to protect blood plasma and platelets against peroxynitrite-induced oxidative damage. The ability of various concentrations of tempol (25, 50, 75, and 100 µM) to antagonize peroxynitrite-induced oxidation was evaluated by measuring the levels of protein carbonyl groups and thiobarbituric-acid-reactive substances in experimental groups. Exposure of platelets and plasma to 100 µM peroxynitrite resulted in an increased levels of carbonyl groups and lipid peroxidation (P < 0.05). Tempol significantly inhibited carbonyl group formation in plasma and platelet proteins (P < 0.05). In addition, tempol significantly reduced the levels of lipid peroxidation in both plasma and platelet samples (P < 0.05). Thus, tempol has antioxidative properties against peroxynitrite-induced oxidative damage in blood plasma and platelets. PMID:25107897

  4. Fucoidan improves serum lipid levels and atherosclerosis through hepatic SREBP-2-mediated regulation.

    PubMed

    Park, Jinhee; Yeom, Mijung; Hahm, Dae-Hyun

    2016-06-01

    Hyperlipidemia is associated with increased risk of the development of cardiovascular diseases. Although a great deal of attention has been paid to the hypolipidemic activity of fucoidan, complex polysaccharides from brown seaweeds, the underlying mechanism is still unclear. This study was performed to investigate whether and how fucoidan has lipid-lowering potential in poloxamer-407 (P407)-induced hyperlipidemic mice. Fucoidan treatment 2 h after acute administration of P407 in these mice significantly reduced serum total cholesterol, triglycerides, and LDL cholesterol levels, but increased the levels of HDL cholesterol. In HepG2 hepatocytes and the liver, fucoidan decreased the expression of FAS and ACC mRNA with no or only a moderate inhibitory effect on SREBP-1c mRNA expression. Furthermore, fucoidan attenuated the hepatic expression of mature SREBP-2 protein with a subsequent decrease in hepatic HMG-CoA reductase mRNA expression and an increase in hepatic LDL receptor mRNA expression. In addition, atherosclerotic lesions in the aorta of chronically P407-treated mice were also reduced by fucoidan. These findings indicate that fucoidan improves serum lipid levels by regulating the expression of key enzymes of cholesterol and triglyceride syntheses in the liver through modulation of SREBP-2.

  5. TPL-2 Regulates Macrophage Lipid Metabolism and M2 Differentiation to Control TH2-Mediated Immunopathology

    PubMed Central

    Entwistle, Lewis J.; Khoury, Hania; Papoutsopoulou, Stamatia; Mahmood, Radma; Mansour, Nuha R.; Ching-Cheng Huang, Stanley; Pearce, Edward J.; Pedro S. de Carvalho, Luiz; Ley, Steven C.

    2016-01-01

    Persistent TH2 cytokine responses following chronic helminth infections can often lead to the development of tissue pathology and fibrotic scarring. Despite a good understanding of the cellular mechanisms involved in fibrogenesis, there are very few therapeutic options available, highlighting a significant medical need and gap in our understanding of the molecular mechanisms of TH2-mediated immunopathology. In this study, we found that the Map3 kinase, TPL-2 (Map3k8; Cot) regulated TH2-mediated intestinal, hepatic and pulmonary immunopathology following Schistosoma mansoni infection or S. mansoni egg injection. Elevated inflammation, TH2 cell responses and exacerbated fibrosis in Map3k8–/–mice was observed in mice with myeloid cell-specific (LysM) deletion of Map3k8, but not CD4 cell-specific deletion of Map3k8, indicating that TPL-2 regulated myeloid cell function to limit TH2-mediated immunopathology. Transcriptional and metabolic assays of Map3k8–/–M2 macrophages identified that TPL-2 was required for lipolysis, M2 macrophage activation and the expression of a variety of genes involved in immuno-regulatory and pro-fibrotic pathways. Taken together this study identified that TPL-2 regulated TH2-mediated inflammation by supporting lipolysis and M2 macrophage activation, preventing TH2 cell expansion and downstream immunopathology and fibrosis. PMID:27487182

  6. Endogenous pro-resolving and anti-inflammatory lipid mediators: a new pharmacologic genus.

    PubMed

    Serhan, C N; Chiang, N

    2008-03-01

    Complete resolution of an acute inflammatory response and its return to homeostasis are essential for healthy tissues. Here, we overview ongoing efforts to characterize cellular and molecular mechanisms that govern the resolution of self-limited inflammation. Systematic temporal analyses of evolving inflammatory exudates using mediator lipidomics-informatics, proteomics, and cellular trafficking with murine resolving exudates demonstrate novel endogenous pathways of local-acting mediators that share both anti-inflammatory and pro-resolving properties. In murine systems, resolving-exudate leukocytes switch their phenotype to actively generate new families of mediators from major omega-3 fatty acids EPA and DHA termed resolvins and protectins. Recent advances on their biosynthesis and actions are reviewed with a focus on the E-series resolvins (RvE1, RvE2), D series resolvins (RvD1, RvD2) and the protectins including neuroprotectin D1/protectin D1 (NPD1/PD1) as well as their aspirin-triggered epimeric forms. Members of each new family demonstrate potent stereo-specific actions, joining the lipoxins as endogenous local signals that govern resolution and endogenous anti-inflammation mechanisms. In addition to their origins and roles in resolution biology in the immune system, recent findings indicate that these new mediator families also display potent protective actions in lung, kidney, and eye as well as enhance microbial clearance. Thus, these endogenous agonists of resolution pathways constitute a novel genus of chemical mediators that possess pro-resolving, anti-inflammatory, and antifibrotic as well as host-directed antimicrobial actions. These may be useful in the design of new therapeutics and treatments for diseases with the underlying trait of uncontrolled inflammation and redox organ stress.

  7. Myoglobin and haemoglobin-mediated lipid oxidation in washed muscle: observations on crosslinking, ferryl formation, porphyrin degradation, and haemin loss rate.

    PubMed

    Lee, Sung Ki; Tatiyaborworntham, Nantawat; Grunwald, Eric W; Richards, Mark P

    2015-01-15

    Reduced trout haemoglobin (Hb) is a mixture of oxy- and deoxy-Hb at pH 6.3. Addition of oxy/deoxyHb to washed muscle resulted in detectable ferryl Hb while adding bovine oxyHb, trout metHb, or bovine metHb did not. Trout metHb promoted lipid oxidation more rapidly than bovine metHb, attributable to lower haemin affinity in fish Hbs. Protoporphyrin IX degradation was prevalent during trout and bovine Hb-mediated lipid oxidation. Caffeic acid prevented porphyrin degradation and lipid oxidation. Crosslinked myoglobin (Mb) promoted lipid oxidation more effectively than metMb. Fish metMb released haemin more readily than mammalian metMb at pH 5.5. These studies suggest haemin dissociation from metHb causes formation of free radicals that degrade protoporphyrin and cause lipid oxidation, and appreciable quantities of deoxyHb are needed to generate ferryl Hb oxidant. Crosslinking appears to facilitate Mb-mediated lipid oxidation in washed muscle yet haemin release can occur from fish metMb at low pH.

  8. Interactions of salicylic acid derivatives with calcite crystals.

    PubMed

    Ukrainczyk, Marko; Gredičak, Matija; Jerić, Ivanka; Kralj, Damir

    2012-01-01

    Investigation of basic interactions between the active pharmaceutical compounds and calcium carbonates is of great importance because of the possibility to use the carbonates as a mineral carrier in drug delivery systems. In this study the mode and extent of interactions of salicylic acid and its amino acid derivates, chosen as pharmaceutically relevant model compounds, with calcite crystals are described. Therefore, the crystal growth kinetics of well defined rhombohedral calcite seed crystals in the systems containing salicylic acid (SA), 5-amino salicylic acid (5-ASA), N-salicyloil-l-aspartic acid (N-Sal-Asp) or N-salicyloil-l-glutamic acid (N-Sal-Glu), were investigated. The precipitation systems were of relatively low initial supersaturation and of apparently neutral pH. The data on the crystal growth rate reductions in the presence of the applied salicylate molecules were analyzed by means of Cabrera & Vermileya's, and Kubota & Mullin's models of interactions of the dissolved additives and crystal surfaces. The crystal growth kinetic experiments were additionally supported with the appropriate electrokinetic, spectroscopic and adsorption measurements. The Langmuir adsorption constants were determined and they were found to be in a good correlation with values obtained from crystal growth kinetic analyses. The results indicated that salicylate molecules preferentially adsorb along the steps on the growing calcite surfaces. The values of average spacing between the adjacent salicylate adsorption active sites and the average distance between the neighboring adsorbed salicylate molecules were also estimated.

  9. Urease inhibitory activities of β-boswellic acid derivatives

    PubMed Central

    2013-01-01

    Background and the purpose of the study Boswellia carterii have been used in traditional medicine for many years for management different gastrointestinal disorders. In this study, we wish to report urease inhibitory activity of four isolated compound of boswellic acid derivative. Methods 4 pentacyclic triterpenoid acids were isolated from Boswellia carterii and identified by NMR and Mass spectroscopic analysis (compounds 1, 3-O-acetyl-9,11-dehydro-β-boswellic acid; 2, 3-O-acetyl-11-hydroxy-β-boswellic acid; 3. 3-O- acetyl-11-keto-β-boswellic acid and 4, 11-keto-β-boswellic acid. Their inhibitory activity on Jack bean urease were evaluated. Docking and pharmacophore analysis using AutoDock 4.2 and Ligandscout 3.03 programs were also performed to explain possible mechanism of interaction between isolated compounds and urease enzyme. Results It was found that compound 1 has the strongest inhibitory activity against Jack bean urease (IC50 = 6.27 ± 0.03 μM), compared with thiourea as a standard inhibitor (IC50 = 21.1 ± 0.3 μM). Conclusion The inhibition potency is probably due to the formation of appropriate hydrogen bonds and hydrophobic interactions between the investigated compounds and urease enzyme active site and confirms its traditional usage. PMID:23351363

  10. Anti-Trichomonas vaginalis activity of betulinic acid derivatives.

    PubMed

    Hübner, Dariana Pimentel Gomes; de Brum Vieira, Patrícia; Frasson, Amanda Piccoli; Menezes, Camila Braz; Senger, Franciane Rios; Santos da Silva, Gloria Narjara; Baggio Gnoatto, Simone Cristina; Tasca, Tiana

    2016-12-01

    Caused by Trichomonas vaginalis, trichomoniasis is the most common non-viral STD worldwide. Currently, metronidazole and tinidazole are the only drugs approved for treatment of the condition. However, problems such as metronidazole-resistant T. vaginalis isolates and allergic reactions have been reported. Based on data previously published by our group, structural changes in betulinic acid (1) were performed, generating three new compounds that were tested for in vitro anti-T.vaginalis activity in this study. Whereas derivative 2 did not demonstrate anti-T. vaginalis activity, derivatives 3 and 4 reduced trophozoite viability by 100%, with MIC values of 50μM. The structural difference of two compounds was performed only on the C-28 position. Derivative 3 showed low cytotoxicity against Vero cells in 24h; however, derivative 4 was highly cytotoxic, but efficient when associated with metronidazole in the synergism assay. ROS production by neutrophils was reduced, and derivative 3 showed anti-inflammatory effect. Collectively, the results of this study provide in vitro evidence that betulinic acid derivatives 3 and 4 are potential compounds with anti-T. vaginalis activity.

  11. Retention of caffeic acid derivatives in dried Echinacea purpurea.

    PubMed

    Kim, H O; Durance, T D; Scaman, C H; Kitts, D D

    2000-09-01

    Different drying methods were applied to fresh Canadian-grown Echinacea purpurea flowers to determine optimal drying procedures for preserving caffeic acid derivatives. Fresh flowers of E. purpurea were dried by freeze-drying (FD), vacuum microwave drying with full vacuum (VMD), and air-drying (AD) at 25, 40, and 70 degrees C. Using HPLC, chicoric acid and caftaric acid levels were quantitated in dried flowers. These acids were significantly affected by the drying method conditions used. Although significant (p < 0.05) loss of chicoric acid was observed when flowers were stored at high moisture, VMD flowers with a low moisture content retained the highest levels of chicoric acid and caftaric acid similar to FD flowers. Flowers that were AD at 25 degrees C retained about 50%, while those dried by AD at 70 degrees C resulted in the lowest retention of these acids. Although flowers dried by AD at 40 degrees C retained relatively high amounts of chicoric acid and caftaric acid, the time (55 h) required to reach optimal drying was considerably longer than that (47 min) for VMD.

  12. Correction of Apolipoprotein A-I-mediated Lipid Efflux and High Density Lipoprotein Particle Formation in Human Niemann-Pick Type C Disease Fibroblasts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Impaired cell cholesterol trafficking in Niemann-Pick type C (NPC) disease results in the first known instance of impaired regulation of the ATP-binding cassette transporter A1 (ABCA1), a lipid transporter mediating the rate-limiting step in high density lipoprotein (HDL) formation, as a cause of lo...

  13. Proinflammatory and lipid biomarkers mediate metabolically healthy obesity: A proteomics study

    PubMed Central

    Zhou, Jie; Zhou, Ming; Prieto, DaRue; Rotimi, Charles N.; Adeyemo, Adebowale

    2016-01-01

    Objective The metabolically healthy obesity (MHO) phenotype is an important obesity subtype in which obesity is not accompanied by any metabolic comorbidity. However, the underlying molecular mechanisms remain elusive. In this study, a shotgun proteomics approach to identify circulating biomolecules and pathways associated with MHO was used. Methods The subjects were 20 African‐American women: 10 MHO cases and 10 metabolically abnormal individuals with obesity (MAO) controls. Serum proteins were detected and quantified using label‐free proteomics. Differential expression of proteins between the two groups was analyzed, and the list of differentially expressed proteins was analyzed to determine enriched biological pathways. Results Twenty proteins were differentially expressed between MHO and controls. These proteins included: hemoglobin subunits (HBA1, P = 6.00 × 10−18), haptoglobin‐related protein (HPR, P = 1.2 × 10−15), apolipoproteins (APOB‐100, P = 1.50 × 10−40; APOA4, P = 1.1 × 10−14), retinol‐binding protein 4 (RBP4, P = 7.1 × 10−08), and CRP (P = 2.0 × 10−04). MHO was associated with lower levels of proinflammatory and higher levels of anti‐inflammatory biomarkers when compared with MAO. Pathway analysis showed enrichment of lipids and inflammatory pathways, including LXR/RXR and FXR/RXR activation, and acute phase response signaling. Conclusions These findings suggested that protection from dysregulated inflammatory and lipid processes were primary molecular hallmarks of MHO. The candidate biomarkers (AHSG, RBP4, and APOA4) identified in this study are potential prognostic markers for MHO. PMID:27106679

  14. [Gene transfer system mediated by PEI-cholesterol lipopolymer with lipid microbubbles].

    PubMed

    Jiang, Yong-Nan; Mo, Hong-Ying; Chen, Jian-Hai

    2010-05-01

    The properties of polyethyleneimine-cholesterol cationic lipopolymer (PEI-Chol) as gene carries and its gene transfer efficiency in vitro with lipid microbubbles were presented in this paper. PEI-Chol lipopolymer was synthesized by linking cholesterol chloroformate to the amino groups of branched poly(ethyleneimine) (PEI) of 1 800. The structure and molecular weight of PEI-Chol were confirmed by IR, 1H NMR and MADI-TOF-MS (matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry), respectively. The average molecular weight of PEI-Chol was approximately 2 000. The gene delivery system of bubble/PEI-Chol/DNA was constructed by mixed PEI-Chol/pDNA (N/P 10:1) complexes with lipid microbubbles (2-8 microm) which were prepared by DPPC, DSPE-PEG2000 and perfluoropropane with the reverse phase evaporation technique. pEGFP-Cl (enhanced green fluorescent protein) was used as report gene to investigate the DNA condensing ability of PEI-Chol lipopolymer by agarose gel electrophoresis. And their cytotoxicity and in vitro transfer efficiency of different complexes were compared with each other in A549 and MCF-7. The results indicated PEI-Chol lipopolymer can condense plasmid DNA when N/P ratio upto 4, PEI-Chol complexes and bubble/PEI-Chol/DNA complexes were nontoxic to A549 and MCF-7 when formulated at the N/P ratio of 10/1 as determined by MTT assay. This bubble/PEI-Chol/DNA delivery system provided good transfer efficiency with other desirable characteristics such as against-precipitation of plasma proteins. In conclusion, bubble/PEI-Chol/DNA complex is a novel non-viral gene delivery system.

  15. Lipid Flippase Subunit Cdc50 Mediates Drug Resistance and Virulence in Cryptococcus neoformans

    PubMed Central

    Huang, Wei; Liao, Guojian; Baker, Gregory M.; Wang, Yina; Lau, Richard; Paderu, Padmaja; Perlin, David S.

    2016-01-01

    ABSTRACT Cryptococcus neoformans is a human fungal pathogen and a major cause of fungal meningitis in immunocompromised individuals. Treatment options for cryptococcosis are limited. Of the two major antifungal drug classes, azoles are active against C. neoformans but exert a fungistatic effect, necessitating long treatment regimens and leaving open an avenue for emergence of azole resistance. Drugs of the echinocandin class, which target the glucan synthase and are fungicidal against a number of other fungal pathogens, such as Candida species, are ineffective against C. neoformans. Despite the sensitivity of the target enzyme to the drug, the reasons for the innate resistance of C. neoformans to echinocandins remain unknown. To understand the mechanism of echinocandin resistance in C. neoformans, we screened gene disruption and gene deletion libraries for mutants sensitive to the echinocandin-class drug caspofungin and identified a mutation of CDC50, which encodes the β-subunit of membrane lipid flippase. We found that the Cdc50 protein localized to membranes and that its absence led to plasma membrane defects and enhanced caspofungin penetration into the cell, potentially explaining the increased caspofungin sensitivity. Loss of CDC50 also led to hypersensitivity to the azole-class drug fluconazole. Interestingly, in addition to functioning in drug resistance, CDC50 was also essential for fungal resistance to macrophage killing and for virulence in a murine model of cryptococcosis. Furthermore, the surface of cdc50Δ cells contained increased levels of phosphatidylserine, which has been proposed to act as a macrophage recognition signal. Together, these results reveal a previously unappreciated role of membrane lipid flippase in C. neoformans drug resistance and virulence. PMID:27165800

  16. Fatty acid amide hydrolase ablation promotes ectopic lipid storage and insulin resistance due to centrally mediated hypothyroidism.

    PubMed

    Brown, Whitney H; Gillum, Matthew P; Lee, Hui-Young; Camporez, Joao Paulo G; Zhang, Xian-man; Jeong, Jin Kwon; Alves, Tiago C; Erion, Derek M; Guigni, Blas A; Kahn, Mario; Samuel, Varman T; Cravatt, Benjamin F; Diano, Sabrina; Shulman, Gerald I

    2012-09-11

    Fatty acid amide hydrolase (FAAH) knockout mice are prone to excess energy storage and adiposity, whereas mutations in FAAH are associated with obesity in humans. However, the molecular mechanism by which FAAH affects energy expenditure (EE) remains unknown. Here we show that reduced energy expenditure in FAAH(-/-) mice could be attributed to decreased circulating triiodothyronine and thyroxine concentrations secondary to reduced mRNA expression of both pituitary thyroid-stimulating hormone and hypothalamic thyrotropin-releasing hormone. These reductions in the hypothalamic-pituitary-thyroid axis were associated with activation of hypothalamic peroxisome proliferating-activated receptor γ (PPARγ), and increased hypothalamic deiodinase 2 expression. Infusion of NAEs (anandamide and palmitoylethanolamide) recapitulated increases in PPARγ-mediated decreases in EE. FAAH(-/-) mice were also prone to diet-induced hepatic insulin resistance, which could be attributed to increased hepatic diacylglycerol content and protein kinase Cε activation. Our data indicate that FAAH deletion, and the resulting increases in NAEs, predispose mice to ectopic lipid storage and hepatic insulin resistance by promoting centrally mediated hypothyroidism.

  17. Differential control of ATGL-mediated lipid droplet degradation by CGI-58 and G0S2.

    PubMed

    Lu, Xin; Yang, Xingyuan; Liu, Jun

    2010-07-15

    Lipid droplets (LDs) are intracellular storage sites for triacylglyerols (TAGs)and steryl esters, and play essential roles in energy metabolism and membrane biosynthesis. Adipose triglyceride lipase (ATGL) is the key enzyme for TAG hydrolysis (lipolysis) in adipocytes and LD degradation in nonadipocyte cells. Lipase activity of ATGL in vivo largely depends on its C-terminal sequence as well as coactivation by CGI-58. Here we demonstrate that the C-terminal hydrophobic domain in ATGL is required for LD targeting and CGI-58-independent LD degradation. Overexpression of wild type ATGL causes a dramatic decrease in LD size and number, whereas a mutant lacking the hydrophobic domain fails to localize to LDs and to affect their morphology. Interestingly, coexpression of CGI-58 is able to promote LD turnover mediated by this ATGL mutant. Recently we have discovered that G0S2 acts as an inhibitor of ATGL activity and ATGL-mediated lipolysis. Here we show that G0S2 binds to ATGL irrelevantly of its activity state or the presence of CGI-58. In G0S2-expressing cells, the combined expression of CGI-58 and ATGL is incapable of stimulating LD turnover. We propose that CGI-58 and G0S2 regulate ATGL via non-competing mechanisms.

  18. Insulin receptor Thr1160 phosphorylation mediates lipid-induced hepatic insulin resistance

    PubMed Central

    Petersen, Max C.; Madiraju, Anila K.; Gassaway, Brandon M.; Marcel, Michael; Nasiri, Ali R.; Butrico, Gina; Marcucci, Melissa J.; Zhang, Dongyan; Abulizi, Abudukadier; Zhang, Xian-Man; Philbrick, William; Hubbard, Stevan R.; Samuel, Varman T.; Rinehart, Jesse

    2016-01-01

    Nonalcoholic fatty liver disease (NAFLD) is a risk factor for type 2 diabetes (T2D), but whether NAFLD plays a causal role in the pathogenesis of T2D is uncertain. One proposed mechanism linking NAFLD to hepatic insulin resistance involves diacylglycerol-mediated (DAG-mediated) activation of protein kinase C-ε (PKCε) and the consequent inhibition of insulin receptor (INSR) kinase activity. However, the molecular mechanism underlying PKCε inhibition of INSR kinase activity is unknown. Here, we used mass spectrometry to identify the phosphorylation site Thr1160 as a PKCε substrate in the functionally critical INSR kinase activation loop. We hypothesized that Thr1160 phosphorylation impairs INSR kinase activity by destabilizing the active configuration of the INSR kinase, and our results confirmed this prediction by demonstrating severely impaired INSR kinase activity in phosphomimetic T1160E mutants. Conversely, the INSR T1160A mutant was not inhibited by PKCε in vitro. Furthermore, mice with a threonine-to-alanine mutation at the homologous residue Thr1150 (InsrT1150A mice) were protected from high fat diet–induced hepatic insulin resistance. InsrT1150A mice also displayed increased insulin signaling, suppression of hepatic glucose production, and increased hepatic glycogen synthesis compared with WT controls during hyperinsulinemic clamp studies. These data reveal a critical pathophysiological role for INSR Thr1160 phosphorylation and provide further mechanistic links between PKCε and INSR in mediating NAFLD-induced hepatic insulin resistance. PMID:27760050

  19. The Important Role of Lipid Raft-Mediated Attachment in the Infection of Cultured Cells by Coronavirus Infectious Bronchitis Virus Beaudette Strain

    PubMed Central

    Guo, Huichen; Huang, Mei; Yuan, Quan; Wei, Yanquan; Gao, Yuan; Mao, Lejiao; Gu, Lingjun; Tan, Yong Wah; Zhong, Yanxin; Liu, Dingxiang; Sun, Shiqi

    2017-01-01

    Lipid raft is an important element for the cellular entry of some viruses, including coronavirus infectious bronchitis virus (IBV). However, the exact role of lipid rafts in the cellular membrane during the entry of IBV into host cells is still unknown. In this study, we biochemically fractionated IBV-infected cells via sucrose density gradient centrifugation after depleting plasma membrane cholesterol with methyl-β-cyclodextrin or Mevastatin. Our results demonstrated that unlike IBV non-structural proteins, IBV structural proteins co-localized with lipid raft marker caveolin-1. Infectivity assay results of Vero cells illustrated that the drug-induced disruption of lipid rafts significantly suppressed IBV infection. Further studies revealed that lipid rafts were not required for IBV genome replication or virion release at later stages. However, the drug-mediated depletion of lipid rafts in Vero cells before IBV attachment significantly reduced the expression of viral structural proteins, suggesting that drug treatment impaired the attachment of IBV to the cell surface. Our results indicated that lipid rafts serve as attachment factors during the early stages of IBV infection, especially during the attachment stage. PMID:28081264

  20. The critical role of ABCG1 and PPARγ/LXRα signaling in TLR4 mediates inflammatory responses and lipid accumulation in vascular smooth muscle cells.

    PubMed

    Cao, Xiaojie; Zhang, Lili; Chen, Chunhai; Wang, Qingsong; Guo, Lu; Ma, Qinlong; Deng, Ping; Zhu, Gang; Li, Binghu; Pi, Yan; Long, Chunyan; Zhang, Lei; Yu, Zhengping; Zhou, Zhou; Li, Jingcheng

    2017-04-01

    Toll-like receptor 4 (TLR4) plays critical roles in vascular inflammation, lipid accumulation and atherosclerosis development. However, the mechanisms underlying these processes are still not well established, especially in vascular smooth muscle cells (VSMCs). ATP-binding cassette transporter G1 (ABCG1) is one of the key genes mediating inflammation and cellular lipid accumulation. The function of TLR4 in regulating the expression of ABCG1 and the underlying molecular mechanisms remain to be elucidated. In this study, we cultured VSMCs from the thoracic aortas of mice and treated the cells with 50 μg/ml oxidized low-density lipoprotein (oxLDL) to activate TLR4 signaling. We observed that activating TLR4 with oxLDL induced inflammatory responses and lipid accumulation in VSMCs. The expression of peroxisome proliferator-activated receptor gamma (PPARγ), liver X receptor alpha (LXRα) and ABCG1 was inhibited by TLR4 activation. However, these effects could be reversed by knocking out TLR4. PPARγ activation by rosiglitazone rescued LXRα and ABCG1 expression and reduced TLR4-induced inflammation and lipid accumulation. Silencing PPARγ expression with a specific small interfering RNA (siRNA) inhibited LXRα and ABCG1 expression and, importantly, enhanced TLR4-induced inflammation and lipid accumulation. In conclusion, ABCG1 expression was down-regulated by TLR4, which induces inflammation and lipid accumulation in VSMCs via PPARγ/LXRα signaling. These findings indicate a novel molecular mechanism underlying TLR4-induced inflammation and lipid accumulation.

  1. Non-receptor-mediated actions are responsible for the lipid-lowering effects of iodothyronines in FaO rat hepatoma cells.

    PubMed

    Grasselli, Elena; Voci, Adriana; Canesi, Laura; Goglia, Fernando; Ravera, Silvia; Panfoli, Isabella; Gallo, Gabriella; Vergani, Laura

    2011-07-01

    Iodothyronines influence lipid metabolism and energy homeostasis. Previous studies demonstrated that 3,5-l-diiodothyronine (T(2)), as well as 3,3',5-L-triiodothyronine (T(3)), was able to both prevent and reverse hepatic steatosis in rats fed a high-fat diet, and this effect depends on a direct action of iodothyronines on the hepatocyte. However, the involvement of thyroid hormone receptors (TRs) in mediating the lipid-lowering effect of iodothyronines was not elucidated. In this study, we investigated the ability of T(2) and T(3) to reduce the lipid overloading using the rat hepatoma FaO cells defective for functional TRs. The absence of constitutive mRNA expression of both TRα1 and TRβ1 in FaO cells was verified by RT-qPCR. To mimic the fatty liver condition, FaO cells were treated with a fatty acid mixture and then exposed to pharmacological doses of T(2) or T(3) for 24 h. Lipid accumulation, mRNA expression of the peroxisome proliferator-activated receptors (PPAR-α, -γ, -δ) the acyl-CoA oxidase (AOX), and the stearoyl CoA desaturase (SCD1), as well as fuel-stimulated O(2) consumption in intact cells, were evaluated. Lipid accumulation was associated with an increase in triacylglycerol content, PPARγ mRNA expression, and a decrease in PPARδ and SCD1 mRNA expression. The addition of T(2) or T(3) to lipid-overloaded cells resulted in i) reduction in lipid content; ii) downregulation of PPARα, PPARγ, and AOX expression; iii) increase in PPARδ expression; and iv) stimulation of mitochondrial uncoupling. These data demonstrate, for the first time, that in the hepatocyte, the lipid-lowering actions of both T(2) and T(3) are not mediated by TRs.

  2. Metabolic engineering of Saccharomyces cerevisiae for production of fatty acid-derived biofuels and chemicals.

    PubMed

    Runguphan, Weerawat; Keasling, Jay D

    2014-01-01

    As the serious effects of global climate change become apparent and access to fossil fuels becomes more limited, metabolic engineers and synthetic biologists are looking towards greener sources for transportation fuels. In recent years, microbial production of high-energy fuels by economically efficient bioprocesses has emerged as an attractive alternative to the traditional production of transportation fuels. Here, we engineered the budding yeast Saccharomyces cerevisiae to produce fatty acid-derived biofuels and chemicals from simple sugars. Specifically, we overexpressed all three fatty acid biosynthesis genes, namely acetyl-CoA carboxylase (ACC1), fatty acid synthase 1 (FAS1) and fatty acid synthase 2 (FAS2), in S. cerevisiae. When coupled to triacylglycerol (TAG) production, the engineered strain accumulated lipid to more than 17% of its dry cell weight, a four-fold improvement over the control strain. Understanding that TAG cannot be used directly as fuels, we also engineered S. cerevisiae to produce drop-in fuels and chemicals. Altering the terminal "converting enzyme" in the engineered strain led to the production of free fatty acids at a titer of approximately 400 mg/L, fatty alcohols at approximately 100mg/L and fatty acid ethyl esters (biodiesel) at approximately 5 mg/L directly from simple sugars. We envision that our approach will provide a scalable, controllable and economic route to this important class of chemicals.

  3. Synthesis and cholinesterase inhibition of cativic acid derivatives.

    PubMed

    Alza, Natalia P; Richmond, Victoria; Baier, Carlos J; Freire, Eleonora; Baggio, Ricardo; Murray, Ana Paula

    2014-08-01

    Alzheimer's disease (AD) is a neurodegenerative disorder associated with memory impairment and cognitive deficit. Most of the drugs currently available for the treatment of AD are acetylcholinesterase (AChE) inhibitors. In a preliminary study, significant AChE inhibition was observed for the ethanolic extract of Grindelia ventanensis (IC₅₀=0.79 mg/mL). This result prompted us to isolate the active constituent, a normal labdane diterpenoid identified as 17-hydroxycativic acid (1), through a bioassay guided fractionation. Taking into account that 1 showed moderate inhibition of AChE (IC₅₀=21.1 μM), selectivity over butyrylcholinesterase (BChE) (IC₅₀=171.1 μM) and that it was easily obtained from the plant extract in a very good yield (0.15% w/w), we decided to prepare semisynthetic derivatives of this natural diterpenoid through simple structural modifications. A set of twenty new cativic acid derivatives (3-6) was prepared from 1 through transformations on the carboxylic group at C-15, introducing a C2-C6 linker and a tertiary amine group. They were tested for their inhibitory activity against AChE and BChE and some structure-activity relationships were outlined. The most active derivative was compound 3c, with an IC₅₀ value of 3.2 μM for AChE. Enzyme kinetic studies and docking modeling revealed that this inhibitor targeted both the catalytic active site and the peripheral anionic site of this enzyme. Furthermore, 3c showed significant inhibition of AChE activity in SH-SY5Y human neuroblastoma cells, and was non-cytotoxic.

  4. Evading P-glycoprotein mediated-efflux chemoresistance using Solid Lipid Nanoparticles.

    PubMed

    Cavaco, Marco C; Pereira, Carolina; Kreutzer, Bruna; Gouveia, Luis F; Silva-Lima, Beatriz; Brito, Alexandra M; Videira, Mafalda

    2017-01-01

    Multidrug resistance (MDR), whereby cancer cells become resistant to the cytotoxic effects of various structurally and mechanistically unrelated chemotherapeutic agents, is a major problem in the clinical treatment of cancer. P-glycoprotein (P-gp) is a transmembrane protein responsible for drug efflux, which decreases drug intracellular bioavailability, consequently decreasing their efficacy against cancer. Solid Lipid Nanoparticles (SLNs) have not only the ability to protect the entrapped drug against proteolytic degradation, but also allow a selective intracellular targeting. Hypothetically, the entrapped drug enter the target cells by different uptake mechanisms, "nanocitose", as compared to the free drug and may evade efflux-transporters, like P-gp. The functional role of P-gp in limiting the permeability of the anticancer drug paclitaxel (Ptx) was assessed in MDA-MB-436 cells. The observed increase in the pharmacologic efficacy of drug entrapped in SLN relatively to the free drug indicates that this system is shielding the drug. Therefore, "blinding" the nanoparticle from the efflux transporters. The effect was confirmed by the decrease expression of P-gp with loaded-SLNs and through the impact on cellular MDR1 expression. Besides the ability to prevent MDR events, functionalization of SLN with a specific antibody against membrane receptors (anti-CD44v6) improves the nanoparticle capability to target selectively malignant cells. This results allow to anticipate that poor clinical outcomes related to tumour P-gp overexpression might be overcome in a near future.

  5. Folic acid mediated solid lipid nanocarriers loaded with docetaxel and oxidized single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Zhu, Xiali; Huang, Shengnan; Xie, Yingxia; Zhang, Huijuan; Hou, Lin; Zhang, Yingjie; Huang, Heqing; Shi, Jinjin; Wang, Lei; Zhang, Zhenzhong

    2014-01-01

    Single-walled carbon nanotubes (SWNT) possess high-near-infrared absorption coefficient, large surface area, and have great potential in drug delivery. In this study, we obtained ultrashort oxidized SWNT (OSWNT) using mixed acid oxidation method. Then, docetaxel (DTX) and folic acid (FA) are conjugated with OSWNT via π- π accumulation and amide linkage, respectively. A targeting and photothermal sensitive drug delivery system FA-DTX-OSWNT-SLN was prepared following a microemulsion technique. The size and zeta potential of FA-DTX-OSWNT-SLN were 182.8 ± 2.8 nm and -34.59 ± 1.50 mV, respectively. TEM images indicated that FA-DTX-OSWNT-SLN was spherical and much darker than general solid lipid nanoparticles (SLN). Furthermore, OSWNT may wind round, insert into or be encapsulated into the nanocarriers. Compared with free DTX, FA-DTX-OSWNT-SLN could efficiently cross cell membranes and afford higher antitumor efficacy in MCF-7 cells in vitro. Meanwhile, the combination of near-infrared laser (NIR) irradiation at 808 nm significantly enhanced cell inhibition. In conclusion, FA-DTX-OSWNT-SLN drug delivery system in combination with 808 nm NIR laser irradiation may be promising for targeting and photothermal cancer therapy with multiple mechanisms in future.

  6. Polyelectrolyte-Mediated Transport of Doxorubicin Through the Bilayer Lipid Membrane

    NASA Astrophysics Data System (ADS)

    Yaroslavov, Alexander A.; Kitaeva, Marina V.; Melik-Nubarov, Nikolay S.; Menger, Frederic M.

    A model is developed for the effect of ionic polymers on the transport of doxorubicin, an antitumor drug, through a bilayer membrane. Accordingly, a protonated (cationic) form of doxorubicin binds to an anionic polymer, poly(acrylic acid), the resulting complex being several hundred nanometers in size. Nevertheless, large complex species associate with neutral egg lecithin liposomes by means of hydrophobic attraction between the doxorubicin and the liposome bilayer. Then, the doxorubicin enters the liposome interior which has been imparted with an acidic buffer to protonate the doxorubicin. The rate of transmembrane Dox permeation decreases when elevating the polyacid-to-doxorubicin ratio. A cationic polymer, polylysine, being coupled with liposomes containing the negative lipid cardiolipin, accelerates membrane transport of doxorubicin with the maximum rate at a complete neutralization of the membrane charge by an interacting polycation. The effect of a polycation on doxorubicin transport becomes more pronounced as small negative liposomes (60-80 nm in diameter) are changed to larger ones (approx. 600 nm in diameter). An opportunity thus opens up for the manipulation of the kinetics of drug uptake by cells and, ultimately, the control of the pharmaceutical action of drugs.

  7. Fucose decorated solid-lipid nanocarriers mediate efficient delivery of methotrexate in breast cancer therapeutics.

    PubMed

    Garg, Neeraj K; Singh, Bhupinder; Jain, Ashay; Nirbhavane, Pradip; Sharma, Rajeev; Tyagi, Rajeev K; Kushwah, Varun; Jain, Sanyog; Katare, Om Prakash

    2016-10-01

    The present study is designed to engineer fucose anchored methotrexate loaded solid lipid nanoparticles (SLNs) to target breast cancer. The developed nano-carriers were characterized with respect to particle size, PDI, zeta potential, drug loading and entrapment, in-vitro release etc. The characterized formulations were used to comparatively assess cellular uptake, cell-viability, apoptosis, lysosomal membrane permeability, bioavailability, biodistribution, changes in tumor volume and animal survival. The ex-vivo results showed greater cellular uptake and better cytotoxicity at lower IC50 of methotrexate in breast cancer cells. Further, we observed increased programmed cell death (apoptosis) with altered lysosomal membrane permeability and better rate of degradation of lysosomal membrane in-vitro. On the other hand, in-vivo evaluation showed maximum bioavailability and tumor targeting efficiency with minimum secondary drug distribution in various organs with formulated and anchored nano-carrier when compared with free drug. Moreover, sizeable reduction in tumor burden was estimated with fucose decorated SLNs as compared to that seen with free MTX and SLNs-MTX. Fucose decorated SLNs showed promising results to develop therapeutic interventions for breast cancer, and paved a way to explore this promising and novel nano-carrier which enables to address breast cancer.

  8. Stereochemical assignment and anti-inflammatory properties of the omega-3 lipid mediator resolvin E3.

    PubMed

    Isobe, Yosuke; Arita, Makoto; Iwamoto, Ryo; Urabe, Daisuke; Todoroki, Hidenori; Masuda, Koji; Inoue, Masayuki; Arai, Hiroyuki

    2013-04-01

    Uncontrolled inflammation is now considered to be a link between many widely occurring diseases. Thus, controlling the innate inflammatory response and its local chemical mediators has been receiving increasing attention. We recently identified a novel family of eicosapentaenoic acid (EPA)-derived mediators produced by eosinophils, denoted as resolvin E3 (RvE3), that possess potent anti-inflammatory actions both in vitro and in vivo. Carbons at 17 and 18 positions are asymmetric and thus the molecule has a total of four potential stereoisomers. Here, we assigned the stereochemistry of the conjugated double bonds and chirality of alcohols present in two natural isomers of RvE3 with four different stereoisomers prepared by total organic synthesis. The complete structures of two natural isomers of RvE3 were determined to be 17R,18S- and 17R,18R-dihydroxy-5Z,8Z,11Z,13E,15E-EPA, respectively. These natural isomers prepared by total organic synthesis displayed a potent anti-inflammatory action by limiting neutrophil infiltrations both in vitro and in vivo. The unnatural stereoisomers were much less active compared with the natural isomers, demonstrating the stereoselective action of RvE3.

  9. Metastasis Stimulation by Hypoxia and Acidosis-Induced Extracellular Lipid Uptake Is Mediated by Proteoglycan-Dependent Endocytosis.

    PubMed

    Menard, Julien A; Christianson, Helena C; Kucharzewska, Paulina; Bourseau-Guilmain, Erika; Svensson, Katrin J; Lindqvist, Eva; Indira Chandran, Vineesh; Kjellén, Lena; Welinder, Charlotte; Bengzon, Johan; Johansson, Maria C; Belting, Mattias

    2016-08-15

    Hypoxia and acidosis are inherent stress factors of the tumor microenvironment and have been linked to increased tumor aggressiveness and treatment resistance. Molecules involved in the adaptive mechanisms that drive stress-induced disease progression constitute interesting candidates of therapeutic intervention. Here, we provide evidence of a novel role of heparan sulfate proteoglycans (HSPG) in the adaptive response of tumor cells to hypoxia and acidosis through increased internalization of lipoproteins, resulting in a lipid-storing phenotype and enhanced tumor-forming capacity. Patient glioblastoma tumors and cells under hypoxic and acidic stress acquired a lipid droplet (LD)-loaded phenotype, and showed an increased recruitment of all major lipoproteins, HDL, LDL, and VLDL. Stress-induced LD accumulation was associated with increased spheroid-forming capacity during reoxygenation in vitro and lung metastatic potential in vivo On a mechanistic level, we found no apparent effect of hypoxia on HSPGs, whereas lipoprotein receptors (VLDLR and SR-B1) were transiently upregulated by hypoxia. Importantly, however, using pharmacologic and genetic approaches, we show that stress-mediated lipoprotein uptake is highly dependent on intact HSPG expression. The functional relevance of HSPG in the context of tumor cell stress was evidenced by HSPG-dependent lipoprotein cell signaling activation through the ERK/MAPK pathway and by reversal of the LD-loaded phenotype by targeting of HSPGs. We conclude that HSPGs may have an important role in the adaptive response to major stress factors of the tumor microenvironment, with functional consequences on tumor cell signaling and metastatic potential. Cancer Res; 76(16); 4828-40. ©2016 AACR.

  10. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  11. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  12. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  13. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  14. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  15. 40 CFR 721.430 - Oxo-substituted amino-al-kanoic acid derivative.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Oxo-substituted amino-al-kanoic acid... Specific Chemical Substances § 721.430 Oxo-substituted amino-al-kanoic acid derivative. (a) Chemical... as oxo-substituted amino al-kan-oic acid derivative (PMN No. P-92-692) is subject to reporting...

  16. 40 CFR 721.430 - Oxo-substituted amino-al-kanoic acid derivative.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Oxo-substituted amino-al-kanoic acid... Specific Chemical Substances § 721.430 Oxo-substituted amino-al-kanoic acid derivative. (a) Chemical... as oxo-substituted amino al-kan-oic acid derivative (PMN No. P-92-692) is subject to reporting...

  17. 40 CFR 721.430 - Oxo-substituted amino-al-kanoic acid derivative.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Oxo-substituted amino-al-kanoic acid... Specific Chemical Substances § 721.430 Oxo-substituted amino-al-kanoic acid derivative. (a) Chemical... as oxo-substituted amino al-kan-oic acid derivative (PMN No. P-92-692) is subject to reporting...

  18. 40 CFR 721.430 - Oxo-substituted amino-al-kanoic acid derivative.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Oxo-substituted amino-al-kanoic acid... Specific Chemical Substances § 721.430 Oxo-substituted amino-al-kanoic acid derivative. (a) Chemical... as oxo-substituted amino al-kan-oic acid derivative (PMN No. P-92-692) is subject to reporting...

  19. 40 CFR 721.430 - Oxo-substituted amino-al-kanoic acid derivative.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Oxo-substituted amino-al-kanoic acid... Specific Chemical Substances § 721.430 Oxo-substituted amino-al-kanoic acid derivative. (a) Chemical... as oxo-substituted amino al-kan-oic acid derivative (PMN No. P-92-692) is subject to reporting...

  20. Glia and mast cells as targets for palmitoylethanolamide, an anti-inflammatory and neuroprotective lipid mediator.

    PubMed

    Skaper, Stephen D; Facci, Laura; Giusti, Pietro

    2013-10-01

    Glia are key players in a number of nervous system disorders. Besides releasing glial and neuronal signaling molecules directed to cellular homeostasis, glia respond also to pro-inflammatory signals released from immune-related cells, with the mast cell being of particular interest. A proposed mast cell-glia communication may open new perspectives for designing therapies to target neuroinflammation by differentially modulating activation of non-neuronal cells normally controlling neuronal sensitization-both peripherally and centrally. Mast cells and glia possess endogenous homeostatic mechanisms/molecules that can be upregulated as a result of tissue damage or stimulation of inflammatory responses. Such molecules include the N-acylethanolamines, whose principal family members are the endocannabinoid N-arachidonoylethanolamine (anandamide), and its congeners N-stearoylethanolamine, N-oleoylethanolamine, and N-palmitoylethanolamine (PEA). A key role of PEA may be to maintain cellular homeostasis when faced with external stressors provoking, for example, inflammation: PEA is produced and hydrolyzed by microglia, it downmodulates mast cell activation, it increases in glutamate-treated neocortical neurons ex vivo and in injured cortex, and PEA levels increase in the spinal cord of mice with chronic relapsing experimental allergic encephalomyelitis. Applied exogenously, PEA has proven efficacious in mast cell-mediated experimental models of acute and neurogenic inflammation. This fatty acid amide possesses also neuroprotective effects, for example, in a model of spinal cord trauma, in a delayed post-glutamate paradigm of excitotoxic death, and against amyloid β-peptide-induced learning and memory impairment in mice. These actions may be mediated by PEA acting through "receptor pleiotropism," i.e., both direct and indirect interactions of PEA with different receptor targets, e.g., cannabinoid CB2 and peroxisome proliferator-activated receptor-alpha.

  1. Lipid peroxidation-derived aldehyde-protein adducts contribute to trichloroethene-mediated autoimmunity via activation of CD4+ T cells.

    PubMed

    Wang, Gangduo; König, Rolf; Ansari, G A S; Khan, M Firoze

    2008-04-01

    Lipid peroxidation is implicated in the pathogenesis of various autoimmune diseases. Lipid peroxidation-derived aldehydes such as malondialdehyde (MDA) and 4-hydroxynonenal (HNE) are highly reactive and bind to proteins, but their role in eliciting an autoimmune response and their contribution to disease pathogenesis remain unclear. To investigate the role of lipid peroxidation in the induction and/or exacerbation of autoimmune response, 6-week-old autoimmune-prone female MRL+/+ mice were treated for 4 weeks with trichloroethene (TCE; 10 mmol/kg, ip, once a week), an environmental contaminant known to induce lipid peroxidation. Sera from TCE-treated mice showed significant levels of antibodies against MDA-and HNE-adducted proteins along with antinuclear antibodies. This suggested that TCE exposure not only caused increased lipid peroxidation, but also accelerated autoimmune responses. Furthermore, stimulation of cultured splenic lymphocytes from both control and TCE-treated mice with MDA-adducted mouse serum albumin (MDA-MSA) or HNE-MSA for 72 h showed significant proliferation of CD4+ T cells in TCE-treated mice as analyzed by flow cytometry. Also, splenic lymphocytes from TCE-treated mice released more IL-2 and IFN-gamma into cultures when stimulated with MDA-MSA or HNE-MSA, suggesting a Th1 cell activation. Thus, our data suggest a role for lipid peroxidation-derived aldehydes in TCE-mediated autoimmune responses and involvement of Th1 cell activation.

  2. Influence of lipids with hydroxyl-containing head groups on Fe2+ (Cu2+)/H2O2-mediated transformation of phospholipids in model membranes.

    PubMed

    Olshyk, Viktoriya N; Melsitova, Inna V; Yurkova, Irina L

    2014-01-01

    Under condition of ROS formation in lipid membranes, free radical reactions can proceed in both hydrophobic (peroxidation of lipids, POL) and polar (free radical fragmentation) parts of the bilayer. Free-radical fragmentation is typical for the lipids containing a hydroxyl group in β-position with respect to an ester or amide bond. The present study has been undertaken to investigate free-radical transformations of phospholipids in model membranes containing lipids able to undergo fragmentation in their polar part. Liposomes from egg yolk lecithin containing saturated or monounsaturated glycero- and sphingolipids were subjected to the action of an HO* - generating system - Fe(2+)(Cu(2+))/H2O2/Asc, and the POL products were investigated. In parallel with this, the effects of monoacylglycerols and scavengers of reactive species on Fe(2+)(Cu(2+))/H2O2/Asc - mediated free-radical fragmentation of phosphatidylglycerols were studied. Hydroxyl-containing sphingolipids and glycerolipids, which undergo free-radical fragmentation under such conditions, manifested antioxidant properties in the model membranes. In the absence of HO groups in the lipid structure, the effect was either pro-oxidant or neutral. Monoacylglycerols slowed down the rate of both peroxidation in the hydrophobic part and free-radical fragmentation in the hydrophilic part of phospholipid membrane. Scavengers of reactive species inhibited the fragmentation of phosphatidylglycerol substantially. Thus, the ability of hydroxyl-containing lipids to undergo free-radical fragmentation in polar part apparently makes a substantial contribution to the mechanism of their protector action.

  3. Membrane protein complexes catalyze both 4- and 3-hydroxylation of cinnamic acid derivatives in monolignol biosynthesis

    PubMed Central

    Chen, Hsi-Chuan; Li, Quanzi; Shuford, Christopher M.; Liu, Jie; Muddiman, David C.; Sederoff, Ronald R.; Chiang, Vincent L.

    2011-01-01

    The hydroxylation of 4- and 3-ring carbons of cinnamic acid derivatives during monolignol biosynthesis are key steps that determine the structure and properties of lignin. Individual enzymes have been thought to catalyze these reactions. In stem differentiating xylem (SDX) of Populus trichocarpa, two cinnamic acid 4-hydroxylases (PtrC4H1 and PtrC4H2) and a p-coumaroyl ester 3-hydroxylase (PtrC3H3) are the enzymes involved in these reactions. Here we present evidence that these hydroxylases interact, forming heterodimeric (PtrC4H1/C4H2, PtrC4H1/C3H3, and PtrC4H2/C3H3) and heterotrimeric (PtrC4H1/C4H2/C3H3) membrane protein complexes. Enzyme kinetics using yeast recombinant proteins demonstrated that the enzymatic efficiency (Vmax/km) for any of the complexes is 70–6,500 times greater than that of the individual proteins. The highest increase in efficiency was found for the PtrC4H1/C4H2/C3H3-mediated p-coumaroyl ester 3-hydroxylation. Affinity purification-quantitative mass spectrometry, bimolecular fluorescence complementation, chemical cross-linking, and reciprocal coimmunoprecipitation provide further evidence for these multiprotein complexes. The activities of the recombinant and SDX plant proteins demonstrate two protein-complex–mediated 3-hydroxylation paths in monolignol biosynthesis in P. trichocarpa SDX; one converts p-coumaric acid to caffeic acid and the other converts p-coumaroyl shikimic acid to caffeoyl shikimic acid. Cinnamic acid 4-hydroxylation is also mediated by the same protein complexes. These results provide direct evidence for functional involvement of membrane protein complexes in monolignol biosynthesis. PMID:22160716

  4. Understanding the connection between platelet-activating factor, a UV-induced lipid mediator of inflammation, immune suppression and skin cancer.

    PubMed

    Damiani, Elisabetta; Ullrich, Stephen E

    2016-07-01

    Lipid mediators of inflammation play important roles in several diseases including skin cancer, the most prevalent type of cancer found in the industrialized world. Ultraviolet (UV) radiation is a complete carcinogen and is the primary cause of skin cancer. UV radiation is also a potent immunosuppressive agent, and UV-induced immunosuppression is a well-known risk factor for skin cancer induction. An essential mediator in this process is the glyercophosphocholine 1-alkyl-2-acetyl-sn-glycero-3-phosphocholine commonly referred to as platelet-activating factor (PAF). PAF is produced by keratinocytes in response to diverse stimuli and exerts its biological effects by binding to a single specific G-protein-coupled receptor (PAF-R) expressed on a variety of cells. This review will attempt to describe how this lipid mediator is involved in transmitting the immunosuppressive signal from the skin to the immune system, starting from its production by keratinocytes, to its role in activating mast cell migration in vivo, and to the mechanisms involved that ultimately lead to immune suppression. Recent findings related to its role in regulating DNA repair and activating epigenetic mechanisms, further pinpoint the importance of this bioactive lipid, which may serve as a critical molecular mediator that links the environment (UVB radiation) to the immune system and the epigenome.

  5. An imbalance between specialized pro-resolving lipid mediators and pro-inflammatory leukotrienes promotes instability of atherosclerotic plaques

    PubMed Central

    Fredman, Gabrielle; Hellmann, Jason; Proto, Jonathan D.; Kuriakose, George; Colas, Romain A.; Dorweiler, Bernhard; Connolly, E. Sander; Solomon, Robert; Jones, David M.; Heyer, Eric J.; Spite, Matthew; Tabas, Ira

    2016-01-01

    Chronic unresolved inflammation plays a causal role in the development of advanced atherosclerosis, but the mechanisms that prevent resolution in atherosclerosis remain unclear. Here, we use targeted mass spectrometry to identify specialized pro-resolving lipid mediators (SPM) in histologically-defined stable and vulnerable regions of human carotid atherosclerotic plaques. The levels of SPMs, particularly resolvin D1 (RvD1), and the ratio of SPMs to pro-inflammatory leukotriene B4 (LTB4), are significantly decreased in the vulnerable regions. SPMs are also decreased in advanced plaques of fat-fed Ldlr−/− mice. Administration of RvD1 to these mice during plaque progression restores the RvD1:LTB4 ratio to that of less advanced lesions and promotes plaque stability, including decreased lesional oxidative stress and necrosis, improved lesional efferocytosis, and thicker fibrous caps. These findings provide molecular support for the concept that defective inflammation resolution contributes to the formation of clinically dangerous plaques and offer a mechanistic rationale for SPM therapy to promote plaque stability. PMID:27659679

  6. Flagella interact with ionic plant lipids to mediate adherence of pathogenic Escherichia coli to fresh produce plants.

    PubMed

    Rossez, Yannick; Holmes, Ashleigh; Wolfson, Eliza B; Gally, David L; Mahajan, Arvind; Pedersen, Henriette L; Willats, William G T; Toth, Ian K; Holden, Nicola J

    2014-07-01

    Bacterial attachment to plant and animal surfaces is generally thought to constitute the initial step in colonization, requiring adherence factors such as flagella and fimbriae. We describe the molecular mechanism underpinning flagella-mediated adherence to plant tissue for the foodborne pathogen, enterohaemorrhagic Escherichia coli. Escherichia coli H7 flagella interacted with a sulphated carbohydrate (carrageenan) on a glycan array, which occurred in a dose-dependent manner. Adherence of E. coli O157 : H-expressing flagella of serotype H7, H6 or H48 to plants associated with outbreaks from fresh produce and to Arabidopsis thaliana, was dependent on flagella interactions with phospholipids and sulpholipids in plasma membranes. Adherence of purified H7 and H48 flagella to carrageenan was reduced at higher concentrations of KH2 PO4 or KCl, showing an ionic basis to the interactions. Purified H7 flagella were observed to physically interact with plasma membranes in spinach plants and in A.thaliana. The results show a specific interaction between E. coli H7, H6 and H48 flagella and ionic lipids in plant plasma membranes. The work extends our understanding of the molecular mechanisms underpinning E.coli flagella targeting of plant hosts and suggests a generic mechanism of recognition common in eukaryotic hosts belonging to different biological kingdoms.

  7. Systemic delivery of proresolving lipid mediators resolvin D2 and maresin 1 attenuates intimal hyperplasia in mice.

    PubMed

    Akagi, Daisuke; Chen, Mian; Toy, Robert; Chatterjee, Anuran; Conte, Michael S

    2015-06-01

    Vascular injury induces a potent inflammatory response that influences vessel remodeling and patency, limiting long-term benefits of cardiovascular interventions such as angioplasty. Specialized proresolving lipid mediators (SPMs) derived from ω-3 polyunsaturated fatty acids [eicosapentaenoic acid and docosahexaenoic acid (DHA)] orchestrate resolution in diverse settings of acute inflammation. We hypothesized that systemic administration of DHA-derived SPMs [resolvin D2 (RvD2) and maresin 1 (MaR1)] would influence vessel remodeling in a mouse model of arterial neointima formation (carotid ligation). In vitro, SPM treatment inhibited mouse aortic smooth muscle cell migration (IC₅₀ ≅ 1 nM) to a PDGF gradient and reduced TNF-α-stimulated p65 translocation, superoxide production, and proinflammatory gene expression (MCP-1). In vivo, adult FVB mice underwent unilateral carotid artery ligation with administration of RvD2, MaR1, or vehicle (100 ng by intraperitoneal injection at 0, 1, 3, 5, and 7 d after ligation). In ligated carotid arteries at 4 d, SPM treatment was associated with reduced cell proliferation and neutrophil and macrophage recruitment and increased polarization of M2 macrophages in the arterial wall. Neointimal hyperplasia (at 14 d) was notably attenuated in RvD2 (62%)- and MaR1 (67%)-treated mice, respectively. Modulation of resolution pathways may offer new opportunities to regulate the vascular injury response and promote vascular homeostasis.

  8. Revealing the mechanism of passive transport in lipid bilayers via phonon-mediated nanometre-scale density fluctuations

    SciTech Connect

    Zhernenkov, Mikhail; Bolmatov, Dima; Soloviov, Dmitry; Zhernenkov, Kirill; Toperverg, Boris P.; Cunsolo, Alessandro; Bosak, Alexey; Cai, Yong

    2016-05-12

    We report the high resolution inelastic x-ray study of the in-plane phonon excitations in dipalmitoyl phosphatidylcholine (DPPC) above and below main transition temperature. In the Lβ' gel phase, we observe high frequency longitudinal phonon mode previously predicted by the molecular dynamics simulations and for the first time, we reveal low frequency weakly dispersive transverse acoustic mode which softens and exhibits a low-frequency phonon gap when the DPPC lipid transitions into the Lα fluid phase. The phonon softening of the high frequency longitudinal excitations and the transformation of the transverse excitations upon the phase transition from the Lβ' to Lα phase is explained within the framework of the phonon theory of liquids. These findings illustrate the importance of the collective dynamics of biomembranes and reveal that hydrocarbon tails can act as an efficient mediator in controlling the passive transport across the bilayer plane.

  9. Megalin- and cubilin-mediated endocytosis of protein-bound vitamins, lipids, and hormones in polarized epithelia.

    PubMed

    Moestrup, S K; Verroust, P J

    2001-01-01

    Polarized epithelia have several functional and morphological similarities, including a high capacity for uptake of various substances present in the fluids facing the apical epithelial surfaces. Studies during the past decade have shown that receptor-mediated endocytosis, rather than nonspecific pinocytosis, accounts for the apical epithelial uptake of many carrier-bound nutrients and hormones. The two interacting receptors of distinct evolutionary origin, megalin and cubilin, are main receptors in this process. Both receptors are apically expressed in polarized epithelia, in which they function as biological affinity matrices for overlapping repertoires of ligands. The ability to bind multiple ligands is accounted for by a high number of replicated low-density lipoprotein receptor type-A repeats in megalin and CUB (complement C1r/C1s, Uegf, and bone morphogenic protein-1) domains in cubilin. Here we summarize and discuss the structural, genetic, and functional aspects of megalin and cubilin, with emphasis on their function as receptors for uptake of protein-associated vitamins, lipids, and hormones.

  10. Effects of Acidification and Alkalinization on the Lipid Emulsion-Mediated Reversal of Toxic Dose Levobupivacaine-Induced Vasodilation in the Isolated Rat Aorta.

    PubMed

    Ok, Seong-Ho; Kim, Won Ho; Yu, Jongsun; Lee, Youngju; Choi, Mun-Jeoung; Lim, Dong Hoon; Hwang, Yeran; Kim, Yeon A; Sohn, Ju-Tae

    2016-01-01

    The goal of this in vitro study was to examine the effects of pre-acidification and pre-akalinization on the lipid emulsion-mediated reversal of toxic dose levobupivacaine-induced vasodilation in isolated rat aorta. Isolated aortic rings with and without the nitric oxide synthase inhibitor N(ω)-nitro-L-arginine methyl ester (L-NAME) were exposed to four types of Krebs solution (pH 7.0, 7.2, 7.4, and 7.6), followed by the addition of 60 mM potassium chloride. When the toxic dose of levobupivacaine (3 × 10(-4) M) produced a stable and sustained vasodilation in the isolated aortic rings that were precontracted with 60 mM potassium chloride, increasing lipid emulsion concentrations (SMOFlipid(®): 0.24, 0.48, 0.95 and 1.39%) were added to generate concentration-response curves. The effects of mild pre-acidification alone and mild pre-acidification in combination with a lipid emulsion on endothelial nitric oxide synthase (eNOS) phosphorylation in human umbilical vein endothelial cells were investigated by Western blotting. Mild pre-acidification caused by the pH 7.2 Krebs solution enhanced the lipid emulsion-mediated reversal of levobupivacaine-induced vasodilation in isolated endothelium-intact aortic rings, whereas mild pre-acidification caused by the pH 7.2 Krebs solution did not significantly alter the lipid emulsion-mediated reversal of the levobupivacaine-induced vasodilation in isolated endothelium-denuded aortic rings or endothelium-intact aortic rings with L-NAME. A lipid emulsion attenuated the increased eNOS phosphorylation induced by the pH 7.2 Krebs solution. Taken together, these results suggest that mild pre-acidification enhances the lipid emulsion-mediated reversal of toxic dose levobupivacaine-induced vasodilation in the endothelium-intact aorta via the inhibition of nitric oxide.

  11. Hypolipidemic and hypoglycemic activities of a oleanolic acid derivative from Malva parviflora on streptozotocin-induced diabetic mice.

    PubMed

    Gutiérrez, Rosa Martha Pérez

    2016-12-10

    One new oleanolic acid derivative, 2α,3β,23α,29α tetrahydroxyolean-12(13)-en-28-oic acid (1) was isolated from the aerial parts of Malva parviflora. Their structure was characterized by spectroscopic methods. The hypolipidemic and hypoglycemic activities of 1 was analyzed in in streptozotocin (STZ)-nicotinamide-induced type 2 diabetes in mice (MD) and type 1 diabetes in streptozotocin-induced diabetic mice (SD). Triterpene was administered orally at doses of 20 mg/kg for 4 weeks. Organ weight, body weight, glucose, fasting insulin, cholesterol-related lipid profile parameters, glutamate oxaloacetate transaminase (SGOT), glutamate pyruvate transaminase (SGPT), serum alkaline phosphatase (SALP), glucokinase, hexokinase, glucose-6-phosphatase activities and glycogen in liver were measured after 4 weeks of treatment. The results indicated that 1 regulate glucose metabolism, lipid profile, lipid peroxidation, increased body weight, glucokinase and hexokinase activities inhibited triglycerides, total cholesterol, low density lipoproteins level, SGOT, SGPT, SALP, glycogen in liver and glucose-6-phosphatase. In addition, improvement of insulin resistance and protective effect for pancreatic β-cells, also 1 may changes the expression of pro-inflammatory cytokine (IL-6 and TNF-α levels) and enzymes (PAL2, COX-2, and LOX). The results suggest that 1 has hypolipidemic and hypoglycemic, anti-inflammatory, activities, improve insulin resistance and hepatic enzymes in streptozotocin-induced diabetic mice.

  12. Primary aminophospholipids in the external layer of liposomes protect their component polyunsaturated fatty acids from 2,2'-azobis(2-amidinopropane)- dihydrochloride-mediated lipid peroxidation.

    PubMed

    Kubo, Kazuhiro; Sekine, Seiji; Saito, Morio

    2005-02-09

    We showed in our previous study that docosahexaenoic acid-rich phosphatidylethanolamine in the external layer of small-size liposomes, as a model for biomembranes, protected its docosahexaenoic acid from 2,2'-azobis(2-amidinopropane)dihydrochloride- (AAPH-) mediated lipid peroxidation in vitro. Besides phosphatidylethanolamine, both phosphatidylserine and an alkenyl-acyl analogue of phosphatidylethanolamine, phosphatidylethanolamine plasmalogen, are reported to possess characteristic antioxidant activities. However, there are few reports about the relationship between the protective activity of phosphatidylethanolamine plasmalogen and/or phosphatidylserine against lipid peroxidation and their distribution in a phospholipid bilayer. Furthermore, it is unclear whether phosphatidylethanolamine plasmalogen and/or phosphatidylserine protect their component polyunsaturated fatty acids (PUFAs) from lipid peroxidation. In the present study, we examined the relationship between the transbilayer distribution of aminophospholipids, such as phosphatidylethanolamine rich in arachidonic acid, phosphatidylethanolamine plasmalogen, and phosphatidylserine, and the oxidative stability of their component PUFAs. The transbilayer distribution of these aminophospholipids in liposomes was modulated by coexisting phosphatidylcholine bearing two types of acyl chain: dipalmitoyl or dioleoyl. The amounts of these primary aminophospholipids in the external layer became significantly higher in liposomes containing dioleoylphosphatidylcholine than in those containing dipalmitoylphosphatidylcholine. Phosphatidylethanolamine rich in arachidonic acid, phosphatidylethanolamine plasmalogen or phosphatidylserine in the external layer of liposomes, as well as external docosahexaenoic acid-rich phosphatidylethanolamine, were able to protect their component PUFAs from AAPH-mediated lipid peroxidation.

  13. P2X1 receptors localized in lipid rafts mediate ATP motor responses in the human vas deferens longitudinal muscles.

    PubMed

    Donoso, María Verónica; Norambuena, Andrés; Navarrete, Camilo; Poblete, Inés; Velasco, Alfredo; Huidobro-Toro, Juan Pablo

    2014-02-01

    To assess the role of the P2X1 receptors (P2X1R) in the longitudinal and circular layers of the human vas deferens, ex vivo-isolated strips or rings were prepared from tissue biopsies to record isometric contractions. To ascertain its membrane distribution, tissue extracts were analyzed by immunoblotting following sucrose gradient ultracentrifugation. ATP, alpha,beta-methylene ATP, or electrical field stimulation elicited robust contractions of the longitudinal layer but not of the circular layer which demonstrated inconsistent responses. Alpha,beta-methylene ATP generated stronger and more robust contractions than ATP. In parallel, prostatic segments of the rat vas deferens were examined. The motor responses in both species were not sustained but decayed within the first minute, showing desensitization to additional applications. Cross-desensitization was established between alpha,beta-methylene ATP or ATP-evoked contractions and electrical field stimulation-induced contractions. Full recovery of the desensitized motor responses required more than 30 min and showed a similar pattern in human and rat tissues. Immunoblot analysis of the human vas deferens extracts revealed a P2X1R oligomer of approximately 200 kDa under nonreducing conditions, whereas dithiothreitol-treated extracts showed a single band of approximately 70 kDa. The P2X1R was identified in ultracentrifugation fractions containing 15%-29% sucrose; the receptor localized in the same fractions as flotillin-1, indicating that it regionalized into smooth muscle lipid rafts. In conclusion, ATP plays a key role in human vas deferens contractile responses of the longitudinal smooth muscle layer, an effect mediated through P2X1Rs.

  14. 40 CFR 721.10039 - Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721.10039 Section... Substances § 721.10039 Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic...

  15. 40 CFR 721.10039 - Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721.10039 Section... Substances § 721.10039 Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic...

  16. 40 CFR 721.10039 - Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721.10039 Section... Substances § 721.10039 Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic...

  17. 40 CFR 721.10039 - Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721.10039 Section... Substances § 721.10039 Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic...

  18. 40 CFR 721.10039 - Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic acid derivative, ammonium salt (generic). 721.10039 Section... Substances § 721.10039 Diethoxybenzenamine derivative, diazotized, coupled with aminonaphthalenesulfonic...

  19. Metabolic engineering of yeast to produce fatty acid-derived biofuels: bottlenecks and solutions

    PubMed Central

    Sheng, Jiayuan; Feng, Xueyang

    2015-01-01

    Fatty acid-derived biofuels can be a better solution than bioethanol to replace petroleum fuel, since they have similar energy content and combustion properties as current transportation fuels. The environmentally friendly microbial fermentation process has been used to synthesize advanced biofuels from renewable feedstock. Due to their robustness as well as the high tolerance to fermentation inhibitors and phage contamination, yeast strains such as Saccharomyces cerevisiae and Yarrowia lipolytica have attracted tremendous attention in recent studies regarding the production of fatty acid-derived biofuels, including fatty acids, fatty acid ethyl esters, fatty alcohols, and fatty alkanes. However, the native yeast strains cannot produce fatty acids and fatty acid-derived biofuels in large quantities. To this end, we have summarized recent publications in this review on metabolic engineering of yeast strains to improve the production of fatty acid-derived biofuels, identified the bottlenecks that limit the productivity of biofuels, and categorized the appropriate approaches to overcome these obstacles. PMID:26106371

  20. Troxerutin improves hepatic lipid homeostasis by restoring NAD(+)-depletion-mediated dysfunction of lipin 1 signaling in high-fat diet-treated mice.

    PubMed

    Zhang, Zi-Feng; Fan, Shao-Hua; Zheng, Yuan-Lin; Lu, Jun; Wu, Dong-Mei; Shan, Qun; Hu, Bin

    2014-09-01

    Recent evidences suggest that NAD(+) depletion leads to abnormal hepatic lipid metabolism in high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD); however, the contributing mechanism is not well understood. Our previous study showed that troxerutin, a trihydroxyethylated derivative of natural bioflavonoid rutin, effectively inhibited obesity, and normalized hyperglycemia and hyperlipidemia in high-cholesterol diet-induced diabetic mice. Here we investigated whether troxerutin improved hepatic lipid metabolism via preventing NAD(+) depletion in HFD-induced NAFLD mouse model and the mechanisms underlying these effects. Our results showed that troxerutin markedly prevented obesity, liver steatosis and injury in HFD-fed mice. Troxerutin largely suppressed oxidative stress-mediated NAD(+)-depletion by increasing nicotinamide phosphoribosyltransferase (NAMPT) protein expression and decreasing poly (ADP-ribose) polymerase-1 (PARP1) protein expression and activity in HFD-treated mouse livers. Consequently, troxerutin remarkably restored Silent mating type information regulation 2 homolog1 (SirT1) protein expression and activity in HFD-treated mouse livers. Therefore, troxerutin promoted SirT1-mediated AMP-activated protein kinase (AMPK) activation to inhibit mammalian target of rapamycin complex 1 (mTORC1) signaling, which enhanced nuclear lipin 1 localization, lowered cytoplasmic lipin 1 localization and the ratio of hepatic Lpin 1β/α. Ultimately, troxerutin improved lipid homeostasis by enhancing fatty acid oxidation and triglyceride secretion, and suppressing lipogenesis in HFD-fed mouse livers. In conclusion, troxerutin displayed beneficial effects on hepatic lipid homeostasis in HFD-induced NAFLD by blocking oxidative stress to restore NAD(+)-depletion-mediated dysfunction of lipin 1 signaling. This study provides novel mechanistic insights into NAFLD pathogenesis and indicates that troxerutin is a candidate for pharmacological intervention of NAFLD

  1. Non-Viral, Lipid-Mediated DNA and mRNA Gene Therapy of the Central Nervous System (CNS): Chemical-Based Transfection.

    PubMed

    Hecker, James G

    2016-01-01

    Appropriate gene delivery systems are essential for successful gene therapy in clinical medicine. Cationic lipid-mediated delivery is an alternative to viral vector-mediated gene delivery. Lipid-mediated delivery of DNA or mRNA is usually more rapid than viral-mediated delivery, offers a larger payload, and has a nearly zero risk of incorporation. Lipid-mediated delivery of DNA or RNA is therefore preferable to viral DNA delivery in those clinical applications that do not require long-term expression for chronic conditions. Delivery of RNA may be preferable to non-viral DNA delivery in some clinical applications, because transit across the nuclear membrane is not necessary and onset of expression with RNA is therefore even faster than with DNA, although both are faster than most viral vectors. Here, we describe techniques for cationic lipid-mediated delivery of nucleic acids encoding reporter genes in a variety of cell lines. We describe optimized formulations and transfection procedures that we previously assessed by bioluminescence and flow cytometry. RNA transfection demonstrates increased efficiency relative to DNA transfection in non-dividing cells. Delivery of mRNA results in onset of expression within 1 h after transfection and a peak in expression 5-7 h after transfection. Duration of expression in eukaryotic cells after mRNA transcript delivery depends on multiple factors, including transcript stability, protein turnover, and cell type. Delivery of DNA results in onset of expression within 5 h after transfection, a peak in expression 24-48 h after transfection, and a return to baseline that can be as long as several weeks after transfection. In vitro results are consistent with our in vivo delivery results, techniques for which are described as well. RNA delivery is suitable for short-term transient gene expression due to its rapid onset, short duration of expression and greater efficiency, particularly in non-dividing cells, while the longer duration and

  2. Activation of integrin α5 mediated by flow requires its translocation to membrane lipid rafts in vascular endothelial cells.

    PubMed

    Sun, Xiaoli; Fu, Yi; Gu, Mingxia; Zhang, Lu; Li, Dan; Li, Hongliang; Chien, Shu; Shyy, John Y-J; Zhu, Yi

    2016-01-19

    Local flow patterns determine the uneven distribution of atherosclerotic lesions. Membrane lipid rafts and integrins are crucial for shear stress-regulated endothelial function. In this study, we investigate the role of lipid rafts and integrin α5 in regulating the inflammatory response in endothelial cells (ECs) under atheroprone versus atheroprotective flow. Lipid raft proteins were isolated from ECs exposed to oscillatory shear stress (OS) or pulsatile shear stress, and then analyzed by quantitative proteomics. Among 396 proteins redistributed in lipid rafts, integrin α5 was the most significantly elevated in lipid rafts under OS. In addition, OS increased the level of activated integrin α5 in lipid rafts through the regulation of membrane cholesterol and fluidity. Disruption of F-actin-based cytoskeleton and knockdown of caveolin-1 prevented the OS-induced integrin α5 translocation and activation. In vivo, integrin α5 activation and EC dysfunction were observed in the atheroprone areas of low-density lipoprotein receptor-deficient (Ldlr(-/-)) mice, and knockdown of integrin α5 markedly attenuated EC dysfunction in partially ligated carotid arteries. Consistent with these findings, mice with haploinsufficency of integrin α5 exhibited a reduction of atherosclerotic lesions in the regions under atheroprone flow. The present study has revealed an integrin- and membrane lipid raft-dependent mechanotransduction mechanism by which atheroprone flow causes endothelial dysfunction.

  3. Modulation by glycyrrhetinic acid derivatives of TPA-induced mouse ear oedema.

    PubMed Central

    Inoue, H.; Mori, T.; Shibata, S.; Koshihara, Y.

    1989-01-01

    1. The anti-inflammatory effects of glycyrrhetinic acid and its derivatives on TPA (12-O-tetradecanoylphorbol-13-acetate)-induced mouse ear oedema were studied. The mechanisms of TPA-induced ear oedema were first investigated with respect to the chemical mediators. 2. The formation of ear oedema reached a maximum 5 h after TPA application (2 micrograms per ear) and the prostaglandin E2 (PGE2) production of mouse ear increased with the oedema formation. 3. TPA-induced ear oedema was prevented by actinomycin D and cycloheximide (0.1 mg per ear, respectively) when applied during 60 min after TPA treatment. 4. Of glycyrrhetinic acid derivatives examined, dihemiphthalate derivatives (IIe, IIe', IIIa, IIIa', IVa, IVa') most strongly inhibited ear oedema on both topical (ID50, 1.6 mg per ear for IIe, 2.0 mg per ear for IIIa and 1.6 mg per ear for IVa) and oral (ID50, 88 mg kg-1 for IIe', 130 mg kg-1 for IIIa' and 92 mg kg-1 for IVa') administration. 5. Glycyrrhetinic acid (Ia) and its derivatives applied 30 min before TPA treatment were much more effective in inhibiting oedema than when applied 30 min after TPA. A dihemiphthalate of triterpenoid compound IVa completely inhibited oedema, even when applied 3 h before TPA treatment. 6. Glycyrrhetinic acid (Ia) and deoxoglycyrrhetol (IIa), the parent compounds, produced little inhibition by oral administration at less than 200 mg kg-1. 7. These results suggest that the dihemiphthalate derivatives of triterpenes derived from glycyrrhetinic acid by chemical modification are useful for the treatment of skin inflammation by both topical and oral application. PMID:2924072

  4. The influence of humic acids derived from earthworm-processed organic wastes on plant growth.

    PubMed

    Atiyeh, R M; Lee, S; Edwards, C A; Arancon, N Q; Metzger, J D

    2002-08-01

    Some effects of humic acids, formed during the breakdown of organic wastes by earthworms (vermicomposting), on plant growth were evaluated. In the first experiment, humic acids were extracted from pig manure vermicompost using the classic alkali/acid fractionation procedure and mixed with a soilless container medium (Metro-Mix 360), to provide a range of 0, 50, 100, 150, 200, 250, 500, 1,000, 2,000, and 4,000 mg of humate per kg of dry weight of container medium, and tomato seedlings were grown in the mixtures. In the second experiment, humates extracted from pig manure and food wastes vermicomposts were mixed with vermiculite to provide a range of 0, 50, 125, 250, 500, 1,000, and 4,000 mg of humate per kg of dry weight of the container medium, and cucumber seedlings were grown in the mixtures. Both tomato and cucumber seedlings were watered daily with a solution containing all nutrients required to ensure that any differences in growth responses were not nutrient-mediated. The incorporation of both types of vermicompost-derived humic acids, into either type of soilless plant growth media, increased the growth of tomato and cucumber plants significantly, in terms of plant heights, leaf areas, shoot and root dry weights. Plant growth increased with increasing concentrations of humic acids incorporated into the medium up to a certain proportion, but this differed according to the plant species, the source of the vermicompost, and the nature of the container medium. Plant growth tended to be increased by treatments of the plants with 50-500 mg/kg humic acids, but often decreased significantly when the concentrations of humic acids derived in the container medium exceeded 500-1,000 mg/kg. These growth responses were most probably due to hormone-like activity of humic acids from the vermicomposts or could have been due to plant growth hormones adsorbed onto the humates.

  5. [Cerebroprotective effect of 3-oxypyridine and succinic acid derivatives in acute phase of alloxan-induced diabetes mellitus in rats].

    PubMed

    Volchegorskiĭ, I A; Rassokhina, L M; Miroshnichenko, I Iu

    2011-01-01

    The effects of original domestic derivatives of 3-oxypyridine and succinic acid (emoxipine, reamberin, and mexidol) on cellular composition of cortical and diencephalic structures in rat brain were studied in parallel with monitoring of behavioral, conditional learning, and metabolic disorders in acute phase of alloxan-induced diabetes in rats. The efficiency of 3-oxypyridine derivatives was compared to the results of alpha-lipoic acid administration. Single administration of emoxipine, reamberin, and mexidol in optimal doses prevented lipofuscin deposition in CA1 field neurocytes in hippocampus and/or increased the amount of terminally differentiated cells ofneuroectodermal lineage (oligodendrocytes, pyramid and basket cells) in this zone ofpaleocortex. Concurrently conditional learning capacity in morbid animals was restored. The cerebroprotective and nootropic effects of emoxipine and reamberin were associated with increased exploration motivation in the open field and were independent of their effects on carbohydrate and lipid metabolism dysfunction. On the contrary, the neuroprotective and nootropic effects of mexidol were associated with additional inhibition of morbid rat activity in the open field and a decrease in the level of circulating products of lipid peroxidation. It is established that 3-oxypyridine and succinic acid derivatives significantly exceed alpha-lipoic acid in terms of neuroprotective effects but exhibit significantly lower hypolipdemic activity in acute phase of alloxan diabetes.

  6. Effects of hydrostatic pressure on lipid bilayer membranes. II. Activation and reaction volumes of carrier mediated ion transport.

    PubMed Central

    Benz, R.; Conti, F.

    1986-01-01

    Measurements of voltage relaxations following brief charge-pulses applied to lipid bilayers have been performed at different hydrostatic pressures in the presence of the neutral carriers cyclo (D-Val-L-Pro-L-Val-D-Pro)3(PV) and valinomycin. From double-exponential relaxations observed in membranes containing PV-K+ complexes estimates were obtained of the amount of membrane absorbed complexes, NMS, and of the rate of complex translocation, kMS. The pressure dependence of kMS corresponded to an activation volume for translocation of approximately 12 cm3/mol independent of ionic strength and K+ concentration. The pressure dependence of NMS strongly varied with K+-concentration suggesting a major role of ion-complexation in solution which is estimated to involve a reaction volume of 25.5 cm3/mol, while the volume of absorption of a PV-K+ complex by the membrane was estimated -7.5 cm3/mol. The relaxations observed in the presence of valinomycin contained three exponentials and could be used to estimate four rate constants and one absorption parameter which characterize the valinomycin-mediated transport. When the transport of Rb+ was tested, the rate constant for the complex dissociation, kD, and the total concentration of free and complexed carriers in the membrane, No, were found to be pressure insensitive. The translocation rates for the complex, kMS and for the free carrier, kS, were instead markedly pressure dependent according to estimated activation volumes in the range of 11 to 18 cm3/mol. The recombination rate constant kR was also pressure dependent according to an activation volume of 12-14 cm3/mol. The study of the valinomycin-K+ transport yielded similar results as far as N.,ks, and kms are concerned, but in this case kR was pressure independent, while kD was increased by pressure. The net volume change associated with the transfer of a free ion to the membrane in the form of a valinomycin-ion complex was nevertheless very similar for K+ and Rb+. It is

  7. Receptor-Mediated Uptake and Intracellular Sorting of Multivalent Lipid Nanoparticles Against the Epidermal Growth Factor Receptor (EGFR) and the Human EGFR 2 (HER2)

    NASA Astrophysics Data System (ADS)

    Tran, David Tu

    In the area of receptor-targeted lipid nanoparticles for drug delivery, efficiency has been mainly focused on cell-specificity, endocytosis, and subsequently effects on bioactivity such as cell growth inhibition. Aspects of targeted liposomal uptake and intracellular sorting are not well defined. This dissertation assessed a series of ligands as targeted functional groups against HER2 and EGFR for liposomal drug delivery. Receptor-mediated uptake, both mono-targeted and dual-targeted to multiple receptors of different ligand valence, and the intracellular sorting of lipid nanoparticles were investigated to improve the delivery of drugs to cancer cells. Lipid nanoparticles were functionalized through a new sequential micelle transfer---conjugation method, while the micelle transfer method was extended to growth factors. Through a combination of both techniques, anti-HER2 and anti-EGFR dual-targeted immunoliposomes with different combinations of ligand valence were developed for comparative studies. With the array of lipid nanoparticles, the uptake and cytotoxicity of lipid nanoparticles in relationship to ligand valence, both mono-targeting and dual-targeting, were evaluated on a small panel of breast cancer cell lines that express HER2 and EGFR of varying levels. Comparable uptake ratios of ligand to expressed receptor and apparent cooperativity were observed. For cell lines that express both receptors, additive dose-uptake effects were also observed with dual-targeted immunoliposomes, which translated to marginal improvements in cell growth inhibition with doxorubicin delivery. Colocalization analysis revealed that ligand-conjugated lipid nanoparticles settle to endosomal compartments similar to their attached ligands. Pathway transregulation and pathway saturation were also observed to affect trafficking. In the end, liposomes routed to the recycling endosomes were never observed to traffic beyond the endosomes nor to be exocytose like recycled ligands. Based on

  8. Lipid rafts mediate the interaction between myelin-associated glycoprotein (MAG) on myelin and MAG-receptors on neurons.

    PubMed

    Vinson, Mary; Rausch, Oliver; Maycox, Peter R; Prinjha, Rab K; Chapman, Debra; Morrow, Rachel; Harper, Alex J; Dingwall, Colin; Walsh, Frank S; Burbidge, Stephen A; Riddell, David R

    2003-03-01

    The interaction between myelin-associated glycoprotein (MAG), expressed at the periaxonal membrane of myelin, and receptors on neurons initiates a bidirectional signalling system that results in inhibition of neurite outgrowth and maintenance of myelin integrity. We show that this involves a lipid-raft to lipid-raft interaction on opposing cell membranes. MAG is exclusively located in low buoyancy Lubrol WX-insoluble membrane fractions isolated from whole brain, primary oligodendrocytes, or MAG-expressing CHO cells. Localisation within these domains is dependent on cellular cholesterol and occurs following terminal glycosylation in the trans-Golgi network, characteristics of association with lipid rafts. Furthermore, a recombinant form of MAG interacts specifically with lipid-raft fractions from whole brain and cultured cerebellar granule cells, containing functional MAG receptors GT1b and Nogo-66 receptor and molecules required for transduction of signal from MAG into neurons. The localisation of both MAG and MAG receptors within lipid rafts on the surface of opposing cells may create discrete areas of high avidity multivalent interaction, known to be critical for signalling into both cell types. Localisation within lipid rafts may provide a molecular environment that facilitates the interaction between MAG and multiple receptors and also between MAG ligands and molecules involved in signal transduction.

  9. Synthesis of new glycyrrhetinic acid derived ring A azepanone, 29-urea and 29-hydroxamic acid derivatives as selective 11β-hydroxysteroid dehydrogenase 2 inhibitors.

    PubMed

    Gaware, Rawindra; Khunt, Rupesh; Czollner, Laszlo; Stanetty, Christian; Da Cunha, Thierry; Kratschmar, Denise V; Odermatt, Alex; Kosma, Paul; Jordis, Ulrich; Classen-Houben, Dirk

    2011-03-15

    Glycyrrhetinic acid, the metabolite of the natural product glycyrrhizin, is a well known nonselective inhibitor of 11β-hydroxysteroid dehydrogenase (11β-HSD) type 1 and type 2. Whereas inhibition of 11β-HSD1 is currently under consideration for treatment of metabolic diseases, such as obesity and diabetes, 11β-HSD2 inhibitors may find therapeutic applications in chronic inflammatory diseases and certain forms of cancer. Recently, we published a series of hydroxamic acid derivatives of glycyrrhetinic acid showing high selectivity for 11β-HSD2. The most potent and selective compound is active against human 11β-HSD2 in the low nanomolar range with a 350-fold selectivity over human 11β-HSD1. Starting from the lead compounds glycyrrhetinic acid and the hydroxamic acid derivatives, novel triterpene type derivatives were synthesized and analyzed for their biological activity against overexpressed human 11β-HSD1 and 11β-HSD2 in cell lysates. Here we describe novel 29-urea- and 29-hydroxamic acid derivatives of glycyrrhetinic acid as well as derivatives with the Beckman rearrangement of the 3-oxime to a seven-membered ring, and the rearrangement of the C-ring from 11-keto-12-ene to 12-keto-9(11)-ene. The combination of modifications on different positions led to compounds comprising further improved selective inhibition of 11β-HSD2 in the lower nanomolar range with up to 3600-fold selectivity.

  10. CD1d-mediated presentation of endogenous lipid antigens by adipocytes requires microsomal triglyceride transfer protein.

    PubMed

    Rakhshandehroo, Maryam; Gijzel, Sanne M W; Siersbæk, Rasmus; Broekema, Marjoleine F; de Haar, Colin; Schipper, Henk S; Boes, Marianne; Mandrup, Susanne; Kalkhoven, Eric

    2014-08-08

    Obesity-induced adipose tissue (AT) dysfunction results in a chronic low-grade inflammation that predisposes to the development of insulin resistance and type 2 diabetes. During the development of obesity, the AT-resident immune cell profile alters to create a pro-inflammatory state. Very recently, CD1d-restricted invariant (i) natural killer T (NKT) cells, a unique subset of lymphocytes that are reactive to so called lipid antigens, were implicated in AT homeostasis. Interestingly, recent data also suggest that human and mouse adipocytes can present such lipid antigens to iNKT cells in a CD1d-dependent fashion, but little is known about the lipid antigen presentation machinery in adipocytes. Here we show that CD1d, as well as the lipid antigen loading machinery genes pro-saposin (Psap), Niemann Pick type C2 (Npc2), α-galactosidase (Gla), are up-regulated in early adipogenesis, and are transcriptionally controlled by CCAAT/enhancer-binding protein (C/EBP)-β and -δ. Moreover, adipocyte-induced Th1 and Th2 cytokine release by iNKT cells also occurred in the absence of exogenous ligands, suggesting the display of endogenous lipid antigen-D1d complexes by 3T3-L1 adipocytes. Furthermore, we identified microsomal triglyceride transfer protein, which we show is also under the transcriptional regulation of C/EBPβ and -δ, as a novel player in the presentation of endogenous lipid antigens by adipocytes. Overall, our findings indicate that adipocytes can function as non-professional lipid antigen presenting cells, which may present an important aspect of adipocyte-immune cell communication in the regulation of whole body energy metabolism and immune homeostasis.

  11. CD1d-mediated Presentation of Endogenous Lipid Antigens by Adipocytes Requires Microsomal Triglyceride Transfer Protein*

    PubMed Central

    Rakhshandehroo, Maryam; Gijzel, Sanne M. W.; Siersbæk, Rasmus; Broekema, Marjoleine F.; de Haar, Colin; Schipper, Henk S.; Boes, Marianne; Mandrup, Susanne; Kalkhoven, Eric

    2014-01-01

    Obesity-induced adipose tissue (AT) dysfunction results in a chronic low-grade inflammation that predisposes to the development of insulin resistance and type 2 diabetes. During the development of obesity, the AT-resident immune cell profile alters to create a pro-inflammatory state. Very recently, CD1d-restricted invariant (i) natural killer T (NKT) cells, a unique subset of lymphocytes that are reactive to so called lipid antigens, were implicated in AT homeostasis. Interestingly, recent data also suggest that human and mouse adipocytes can present such lipid antigens to iNKT cells in a CD1d-dependent fashion, but little is known about the lipid antigen presentation machinery in adipocytes. Here we show that CD1d, as well as the lipid antigen loading machinery genes pro-saposin (Psap), Niemann Pick type C2 (Npc2), α-galactosidase (Gla), are up-regulated in early adipogenesis, and are transcriptionally controlled by CCAAT/enhancer-binding protein (C/EBP)-β and -δ. Moreover, adipocyte-induced Th1 and Th2 cytokine release by iNKT cells also occurred in the absence of exogenous ligands, suggesting the display of endogenous lipid antigen-D1d complexes by 3T3-L1 adipocytes. Furthermore, we identified microsomal triglyceride transfer protein, which we show is also under the transcriptional regulation of C/EBPβ and –δ, as a novel player in the presentation of endogenous lipid antigens by adipocytes. Overall, our findings indicate that adipocytes can function as non-professional lipid antigen presenting cells, which may present an important aspect of adipocyte-immune cell communication in the regulation of whole body energy metabolism and immune homeostasis. PMID:24966328

  12. Stabilization of caffeic acid derivatives in Echinacea purpurea L. glycerin extract.

    PubMed

    Bergeron, Chantal; Gafner, Stefan; Batcha, Laura L; Angerhofer, Cindy K

    2002-07-03

    Recent work has shown that enzymatic degradation and oxidation of cichoric acid and other caffeic derivatives occurs in Echinacea preparations. However, very little is known as to the means of stabilizing these phytopreparations. To stabilize the glycerin extract of Echinacea purpurea, we have evaluated the effects of 3 natural antioxidants (citric acid, malic acid, and hibiscus extract) on the stability of the major caffeic acid derivatives (caftaric acid, caffeic acid, cichoric acid, and 2-O-feruloyl-tartaric acid). Chlorogenic acid, which normally occurs in an ethanol extract of E. purpurea, was not present in the glycerin extract. The caffeic acid derivatives, with the exception of 2-O-feruloyl-tartaric acid, were subject to degradation in the control sample. 2-O-Feruloyl-tartaric acid was stable during the whole testing period. All antioxidant treatments greatly improved the stability of caffeic acid derivatives. Stability was dependent upon the concentration of antioxidant added.

  13. Possible protective effect of membrane lipid rafts against interleukin-1β-mediated anti-proliferative effect in INS-1 cells.

    PubMed

    Chentouf, Myriam; Guzman, Caroline; Hamze, Moustafa; Gross, René; Lajoix, Anne Dominique; Peraldi-Roux, Sylvie

    2014-01-01

    We recently reported that pancreatic islets from pre-diabetic rats undergo an inflammatory process in which IL-1β takes part and controls β-cell function. In the present study, using the INS-1 rat pancreatic β-cell line, we investigated the potential involvement of membrane-associated cholesterol-enriched lipid rafts in IL-1β signaling and biological effects on insulin secretion, β-cell proliferation and apoptosis. We show that, INS-1 cells exposure to increasing concentrations of IL-1β leads to a progressive inhibition of insulin release, an increase in the number of apoptotic cells and a dose-dependent decrease in pancreatic β-cell proliferation. Disruption of membrane lipid rafts markedly reduced glucose-stimulated insulin secretion but did not affect either cell apoptosis or proliferation rate, demonstrating that membrane lipid raft integrity is essential for β-cell secretory function. In the same conditions, IL-1β treatment of INS-1 cells led to a slight further decrease in insulin secretion for low concentrations of the cytokine, and a more marked one, similar to that observed in normal cells for higher concentrations. These effects occurred together with an increase in iNOS expression and surprisingly with an upregulation of tryptophane hydroxylase and protein Kinase C in membrane lipid rafts suggesting that compensatory mechanisms develop to counteract IL-1β inhibitory effects. We also demonstrate that disruption of membrane lipid rafts did not prevent cytokine-induced cell death recorded after exposure to high IL-1β concentrations. Finally, concerning cell proliferation, we bring strong evidence that membrane lipid rafts exert a protective effect against IL-1β anti-proliferative effect, possibly mediated at least partly by modifications in ERK and PKB expression/activities. Our results 1) demonstrate that IL-1β deleterious effects do not require a cholesterol-dependent plasma membrane compartmentalization of IL-1R1 signaling and 2) confer to

  14. Synthesis, in vitro and in vivo antitumor activity of pyrazole-fused 23-hydroxybetulinic acid derivatives.

    PubMed

    Zhang, Hengyuan; Zhu, Peiqing; Liu, Jie; Lin, Yan; Yao, Hequan; Jiang, Jieyun; Ye, Wencai; Wu, Xiaoming; Xu, Jinyi

    2015-02-01

    A collection of pyrazole-fused 23-hydroxybetulinic acid derivatives were designed, synthesized and evaluated for their antitumor activity. Most of the newly synthesized compounds exhibited significant antiproliferative activity. Especially compound 15e displayed the most potent activity with the IC50 values of 5.58 and 6.13μM against B16 and SF763 cancer cell lines, respectively. Furthermore, the significant in vivo antitumor activity of 15e was validated in H22 liver cancer and B16 melanoma xenograft mouse models. The structure-activity relationships of these 23-hydroxybetulinic acid derivatives were also discussed based on the present investigation.

  15. Revealing the mechanism of passive transport in lipid bilayers via phonon-mediated nanometre-scale density fluctuations

    PubMed Central

    Zhernenkov, Mikhail; Bolmatov, Dima; Soloviov, Dmitry; Zhernenkov, Kirill; Toperverg, Boris P.; Cunsolo, Alessandro; Bosak, Alexey; Cai, Yong Q.

    2016-01-01

    The passive transport of molecules through a cell membrane relies on thermal motions of the lipids. However, the nature of transmembrane transport and the precise mechanism remain elusive and call for a comprehensive study of phonon excitations. Here we report a high resolution inelastic X-ray scattering study of the in-plane phonon excitations in 1,2-dipalmitoyl-sn-glycero-3-phosphocholine above and below the main transition temperature. In the gel phase, for the first time, we observe low-frequency transverse modes, which exhibit a phonon gap when the lipid transitions into the fluid phase. We argue that the phonon gap signifies the formation of short-lived nanometre-scale lipid clusters and transient pores, which facilitate the passive molecular transport across the bilayer plane. Our findings suggest that the phononic motion of the hydrocarbon tails provides an effective mechanism of passive transport, and illustrate the importance of the collective dynamics of biomembranes. PMID:27175859

  16. Revealing the mechanism of passive transport in lipid bilayers via phonon-mediated nanometre-scale density fluctuations

    SciTech Connect

    Zhernenkov, Mikhail; Bolmatov, Dima; Soloviov, Dmitry; Zhernenkov, Kirill; Toperverg, Boris P.; Cunsolo, Alessandro; Bosak, Alexey; Cai, Yong Q.

    2016-05-12

    The passive transport of molecules through a cell membrane relies on thermal motions of the lipids. However, the nature of transmembrane transport and the precise mechanism remain elusive and call for a comprehensive study of phonon excitations. Here we report a high resolution inelastic X-ray scattering study of the in-plane phonon excitations in 1,2-dipalmitoyl-sn-glycero-3-phosphocholine above and below the main transition temperature. In the gel phase, for the first time, we observe low-frequency transverse modes, which exhibit a phonon gap when the lipid transitions into the fluid phase. We argue that the phonon gap signifies the formation of short-lived nanometre-scale lipid clusters and transient pores, which facilitate the passive molecular transport across the bilayer plane. Finally, our findings suggest that the phononic motion of the hydrocarbon tails provides an effective mechanism of passive transport, and illustrate the importance of the collective dynamics of biomembranes.

  17. Dose-dependent effects of siRNA-mediated inhibition of SCAP on PCSK9, LDLR, and plasma lipids in mouse and rhesus monkey[S

    PubMed Central

    Jensen, Kristian K.; Tadin-Strapps, Marija; Wang, Sheng-ping; Hubert, James; Kan, Yanqing; Ma, Yong; McLaren, David G.; Previs, Stephen F.; Herath, Kithsiri B.; Mahsut, Ablatt; Liaw, Andy; Wang, Shubing; Stout, Steven J.; Keohan, CarolAnn; Forrest, Gail; Coelho, David; Yendluri, Satya; Williams, Stephanie; Koser, Martin; Bartz, Steven; Akinsanya, Karen O.; Pinto, Shirly

    2016-01-01

    SREBP cleavage-activating protein (SCAP) is a key protein in the regulation of lipid metabolism and a potential target for treatment of dyslipidemia. SCAP is required for activation of the transcription factors SREBP-1 and -2. SREBPs regulate the expression of genes involved in fatty acid and cholesterol biosynthesis, and LDL-C clearance through the regulation of LDL receptor (LDLR) and PCSK9 expression. To further test the potential of SCAP as a novel target for treatment of dyslipidemia, we used siRNAs to inhibit hepatic SCAP expression and assess the effect on PCSK9, LDLR, and lipids in mice and rhesus monkeys. In mice, robust liver Scap mRNA knockdown (KD) was achieved, accompanied by dose-dependent reduction in SREBP-regulated gene expression, de novo lipogenesis, and plasma PCSK9 and lipids. In rhesus monkeys, over 90% SCAP mRNA KD was achieved resulting in approximately 75, 50, and 50% reduction of plasma PCSK9, TG, and LDL-C, respectively. Inhibition of SCAP function was demonstrated by reduced expression of SREBP-regulated genes and de novo lipogenesis. In conclusion, siRNA-mediated inhibition of SCAP resulted in a significant reduction in circulating PCSK9 and LDL-C in rodent and primate models supporting SCAP as a novel target for the treatment of dyslipidemia. PMID:27707816

  18. Regulation of lipid and glucose homeostasis by mango tree leaf extract is mediated by AMPK and PI3K/AKT signaling pathways.

    PubMed

    Zhang, Yi; Liu, Xuefeng; Han, Lifeng; Gao, Xiumei; Liu, Erwei; Wang, Tao

    2013-12-01

    Ethanolic extract of Mangifera indica (mango) dose-dependently decreased serum glucose and triglyceride in KK-A(y) mice. Our in vitro and in vivo investigations revealed that the effect of mango leave extract (ME) on glucose and lipid homeostasis is mediated, at least in part, through the PI3K/AKT and AMPK signaling pathway. ME up-regulated the expression of PI3K, AKT and GYS genes by 2.0-fold, 3.2-fold, and 2.7-fold, respectively, leading to a decrease in glucose level. On the other hand, ME up-regulated AMPK and altered lipid metabolism. ME also down-regulated ACC (2.8-fold), HSL (1.6-fold), FAS (1.8-fold) and PPAR-γ (4.0-fold). Finally, we determined that active metabolites of benzophenone C-glucosides, Iriflophenone 3-C-β-glucoside and Foliamangiferoside A from ME, may play a dominant role in this integrated regulation of sugar and lipid homeostasis.

  19. A comparison of heart rate variability, n-3 PUFA status and lipid mediator profile in age- and BMI-matched middle-aged vegans and omnivores.

    PubMed

    Pinto, Ana M; Sanders, Thomas A B; Kendall, Alexandra C; Nicolaou, Anna; Gray, Robert; Al-Khatib, Haya; Hall, Wendy L

    2017-04-03

    Low heart rate variability (HRV) predicts sudden cardiac death. Long-chain (LC) n-3 PUFA (C20-C22) status is positively associated with HRV. This cross-sectional study investigated whether vegans aged 40-70 years (n 23), whose diets are naturally free from EPA (20 : 5n-3) and DHA (22 : 6n-3), have lower HRV compared with omnivores (n 24). Proportions of LC n-3 PUFA in erythrocyte membranes, plasma fatty acids and concentrations of plasma LC n-3 PUFA-derived lipid mediators were significantly lower in vegans. Day-time interbeat intervals (IBI), adjusted for physical activity, age, BMI and sex, were significantly shorter in vegans compared with omnivores (mean difference -67 ms; 95 % CI -130, -3·4, P50 % and high-frequency power) were similarly lower in vegans, with no differences during sleep. In conclusion, vegans have higher 24 h SDNN, but lower day-time HRV and shorter day-time IBI relative to comparable omnivores. Vegans may have reduced availability of precursor markers for pro-resolving lipid mediators; it remains to be determined whether there is a direct link with impaired cardiac function in populations with low-n-3 status.

  20. Experimental Evidence of ω-3 Polyunsaturated Fatty Acid Modulation of Inflammatory Cytokines and Bioactive Lipid Mediators: Their Potential Role in Inflammatory, Neurodegenerative, and Neoplastic Diseases

    PubMed Central

    Calviello, Gabriella; Su, Hui-Min; Weylandt, Karsten H.; Fasano, Elena; Serini, Simona; Cittadini, Achille

    2013-01-01

    A large body of evidence has emerged over the past years to show the critical role played by inflammation in the pathogenesis of several diseases including some cardiovascular, neoplastic, and neurodegenerative diseases, previously not considered inflammation-related. The anti-inflammatory action of ω-3 polyunsaturated fatty acids (PUFAs), as well as their potential healthy effects against the development and progression of the same diseases, has been widely studied by our and others' laboratories. As a result, a rethinking is taking place on the possible mechanisms underlying the beneficial effects of ω-3 PUFAs against these disorders, and, in particular, on the influence that they may exert on the molecular pathways involved in inflammatory process, including the production of inflammatory cytokines and lipid mediators active in the resolving phase of inflammation. In the present review we will summarize and discuss the current knowledge regarding the modulating effects of ω-3 PUFAs on the production of inflammatory cytokines and proresolving or protective lipid mediators in the context of inflammatory, metabolic, neurodegenerative, and neoplastic diseases. PMID:23691510

  1. Vibrio vulnificus VvpE inhibits mucin 2 expression by hypermethylation via lipid raft-mediated ROS signaling in intestinal epithelial cells

    PubMed Central

    Lee, S-J; Jung, Y H; Oh, S Y; Jang, K K; Lee, H S; Choi, S H; Han, H J

    2015-01-01

    Mucin is an important physical barrier against enteric pathogens. VvpE is an elastase encoded by Gram-negative bacterium Vibrio vulnificus; however, the functional role of VvpE in intestinal mucin (Muc) production is yet to be elucidated. The recombinant protein (r) VvpE significantly reduced the level of Muc2 in human mucus-secreting HT29-MTX cells. The repression of Muc2 induced by rVvpE was highly susceptible to the knockdown of intelectin-1b (ITLN) and sequestration of cholesterol by methyl-β-cyclodextrin. We found that rVvpE induces the recruitment of NADPH oxidase 2 and neutrophil cytosolic factor 1 into the membrane lipid rafts coupled with ITLN to facilitate the production of reactive oxygen species (ROS). The bacterial signaling of rVvpE through ROS production is uniquely mediated by the phosphorylation of ERK, which was downregulated by the silencing of the PKCδ. Moreover, rVvpE induced region-specific methylation in the Muc2 promoter to promote the transcriptional repression of Muc2. In two mouse models of V. vulnificus infection, the mutation of the vvpE gene from V. vulnificus exhibited an increased survival rate and maintained the level of Muc2 expression in intestine. These results demonstrate that VvpE inhibits Muc2 expression by hypermethylation via lipid raft-mediated ROS signaling in the intestinal epithelial cells. PMID:26086960

  2. Total synthesis of the lipid mediator PD1n-3 DPA: configurational assignments and anti-inflammatory and pro-resolving actions.

    PubMed

    Aursnes, Marius; Tungen, Jørn E; Vik, Anders; Colas, Romain; Cheng, Chien-Yee C; Dalli, Jesmond; Serhan, Charles N; Hansen, Trond V

    2014-04-25

    The polyunsaturated lipid mediator PD1n-3 DPA (5) was recently isolated from self-resolving inflammatory exudates of 5 and human macrophages. Herein, the first total synthesis of PD1n-3 DPA (5) is reported in 10 steps and 9% overall yield. These efforts, together with NMR data of its methyl ester 6, confirmed the structure of 5 to be (7Z,10R,11E,13E,15Z,17S,19Z)-10,17-dihydroxydocosa-7,11,13,15,19-pentaenoic acid. The proposed biosynthetic pathway, with the involvement of an epoxide intermediate, was supported by results from trapping experiments. In addition, LC-MS/MS data of the free acid 5, obtained from hydrolysis of the synthetic methyl ester 6, matched data for the endogenously produced biological material. The natural product PD1n-3 DPA (5) demonstrated potent anti-inflammatory properties together with pro-resolving actions stimulating human macrophage phagocytosis and efferocytosis. These results contribute new knowledge on the n-3 DPA structure-function of the growing numbers of specialized pro-resolving lipid mediators and pathways.

  3. Identification of cytochrome CYP2E1 as critical mediator of synergistic effects of alcohol and cellular lipid accumulation in hepatocytes in vitro

    PubMed Central

    Mahli, Abdo; Thasler, Wolfgang E.; Patsenker, Eleonora; Müller, Sebastian; Stickel, Felix; Müller, Martina; Seitz, Helmut K.; Cederbaum, Arthur I.; Hellerbrand, Claus

    2015-01-01

    Clinical studies propose a causative link between the consumption of alcohol and the development and progression of liver disease in obese individuals. However, it is incompletely understood how alcohol and obesity interact and whether the combined effects are additive or synergistic. In this study, we developed an in vitro model to address this question. Lipid accumulation in primary human hepatocytes was induced by incubation with oleic acid. Subsequently, steatotic and control hepatocytes were incubated with up to 50 mM alcohol. This alcohol concentration on its own revealed only minimal effects but significantly enhanced oleate-induced lipogenesis and cellular triglyceride content compared to control cells. Similarly, lipid peroxidation, oxidative stress and pro-inflammatory gene expression as well as CYP2E1 levels and activity were synergistically induced by alcohol and steatosis. CYP2E1 inhibition blunted these synergistic pathological effects. Notably, alcohol and cellular steatosis also induced autophagy in a synergistic manner, and also this was mediated via CYP2E1. Further induction of autophagy ameliorated the joint effects of alcohol and oleic acid on hepatocellular lipid accumulation and inflammatory gene expression while inhibition of autophagy further enhanced the dual pathological effects. Further analyses revealed that the joint synergistic effect of alcohol and steatosis on autophagy was mediated via activation of the JNK-pathway. In summary, our data indicate that alcohol induces not only pathological but also protective mechanisms in steatotic hepatocytes via CYP2E1. These findings may have important implications on the prognosis and treatment of alcoholic liver disease particularly in obese individuals. PMID:26497211

  4. Compare ultrasound-mediated heating and cavitation between flowing polymer- and lipid-shelled microbubbles during focused ultrasound exposures.

    PubMed

    Zhang, Siyuan; Zong, Yujin; Wan, Mingxi; Yu, Xiaojun; Fu, Quanyou; Ding, Ting; Zhou, Fanyu; Wang, Supin

    2012-06-01

    This paper compares the efficiency of flowing polymer- and lipid-shelled microbubbles (MBs) in the heating and cavitation during focused ultrasound exposures. Temperature and cavitation activity were simultaneously measured as the two types of shelled MBs and saline flowing through a 3 mm diameter vessel in the phantom with varying flow velocities (0-20 cm/s) at different acoustic power levels (0.6-20 W) with each exposure for 5 s. Temperature and cavitation for the lipid-shelled MBs were higher than those for the polymer-shelled MBs. Temperature rise decreased with increasing flow velocities for the two types of shelled MBs and saline at acoustic power 1.5 W. At acoustic power 11.1 W, temperature rise increased with increasing flow velocities for the lipid-shelled MBs. For the polymer-shelled MBs, the temperature rise increased with increasing flow velocities from 3-15 cm/s and decreased at 20 cm/s. Cavitation increased with increasing flow velocity for the two shelled MBs and there were no significant changes of cavitation with increasing flow velocities for saline. These results suggested that lipid-shelled MBs may have a greater efficiency than polymer-shelled MBs in heating and cavitation during focused ultrasound exposures.

  5. Proatherogenic Abnormalities Of Lipid Metabolism In SirT1 Transgenic Mice Are Mediated Through Creb Deacetylation

    PubMed Central

    Qiang, Li; Lin, Hua V.; Kim-Muller, Ja Young; Welch, Carrie L.; Gu, Wei; Accili, Domenico

    2011-01-01

    SUMMARY Dyslipidemia and atherosclerosis are associated with reduced insulin sensitivity and diabetes, but the mechanism is unclear. Gain-of-function of the gene encoding deacetylase SirT1 improves insulin sensitivity, and could be expected to protect against lipid abnormalities. Surprisingly, when transgenic mice overexpressing SirT1 (SirBACO) are placed on atherogenic diet, they maintain better glucose homeostasis, but develop worse lipid profiles and larger atherosclerotic lesions than controls. We show that transcription factor cAMP response element binding protein (Creb) is deacetylated in SirBACO mice. We identify Lys136 is a substrate for SirT1-dependent deacetylation that affects Creb activity by preventing its cAMP-dependent phosphorylation, leading to reduced expression of glucogenic genes, and promoting hepatic lipid accumulation and secretion. Expression of constitutively acetylated Creb (K136Q) in SirBACO mice mimics Creb activation and abolishes the dyslipidemic and insulin-sensitizing effects of SirT1 gain-of-function. We propose that SirT1-dependent Creb deacetylation regulates the balance between glucose and lipid metabolism, integrating fasting signals. PMID:22078933

  6. Fast and efficient charge transport across a lipid bilayer is electronically mediated by C{sub 70} fullerene aggregates

    SciTech Connect

    Niu, S.; Mauzerall, D.

    1996-06-19

    Fullerene anions, made by photoreduction in a lipid bilayer, produce the largest trans-membrane steady state photocurrents yet observed, nearly 6.0 {mu}A/cm{sup 2}. Since these photocurrents are not light saturated, their maximum value is considerably larger. Dithionite was used as electron donor for its ability to reduce photoexcited fullerenes at the donor interface on a time scale faster than 15 ns. Both photovoltage and photocurrent increase 15-fold on adding the acceptor ferricyanide trans to the donor. There are two components to the transit time of negative charge across the bilayer, <100 ns and 6 {mu}s, in the 100 mM dithionite 0.6 mM C{sub 70} 5 mM ferricyanide system, where stands for the water-bilayer interface. This is strong evidence that the conduction is electronic and not diffusive-ionic. The plot of the ratio of photovoltage for the dithionite C{sub 70} system to that of the dithionite C{sub 70} ferricyanide system versus concentration of C{sub 70} in the lipid-forming solution is highly monlinear. This suggests that aggregates of the fullerene are responsible for the fast negative charge transport. The action spectrum of the photocurrent further supports the existence of photoactive C{sub 70} aggregates in the lipid bilayer. These aggregates may form the conductive path for electrons across the lipid bilayer. 23 refs., 5 figs., 1 tab.

  7. Archaeosomes varying in lipid composition differ in receptor-mediated endocytosis and differentially adjuvant immune responses to entrapped antigen

    PubMed Central

    Sprott, G. Dennis; Sad, Subash; Fleming, L. Perry; DiCaire, Chantal J.; Patel, Girishchandra B.; Krishnan, Lakshmi

    2003-01-01

    Archaeosomes prepared from total polar lipids extracted from six archaeal species with divergent lipid compositions had the capacity to deliver antigen for presentation via both MHC class I and class II pathways. Lipid extracts from Halobacterium halobium and from Halococcus morrhuae strains 14039 and 16008 contained archaetidylglycerol methylphosphate and sulfated glycolipids rich in mannose residues, and lacked archaetidylserine, whereas the opposite was found in Methanobrevibacter smithii, Methanosarcina mazei and Methanococcus jannaschii. Annexin V labeling revealed a surface orientation of phosphoserine head groups in M. smithii, M. mazei and M. jannaschii archaeosomes. Uptake of rhodamine-labeled M. smithii or M. jannaschii archaeosomes by murine peritoneal macrophages was inhibited by unlabeled liposomes containing phosphatidylserine, by the sulfhydryl inhibitor N-ethylmaleimide, and by ATP depletion using azide plus fluoride, but not by H. halobium archaeosomes. In contrast, N-ethylmaleimide failed to inhibit uptake of the four other rhodamine-labeled archaeosome types, and azide plus fluoride did not inhibit uptake of H. halobium or H. morrhuae archaeosomes. These results suggest endocytosis ofarchaeosomes rich in surface-exposed phosphoserine head groups via a phosphatidylserine receptor, and energy-independent surface adsorption of certain other archaeosome composition classes. Lipid composition affected not only the endocytic mechanism, but also served to differentially modulate the activation of dendritic cells. The induction of IL-12 secretion from dendritic cells exposed to H. morrhuae 14039 archaeosomes was striking compared with cells exposed to archaeosomes from 16008. Thus, archaeosome types uniquely modulate antigen delivery and dendritic cell activation. PMID:15803661

  8. Effects of Vanadium-Containing Compounds on Membrane Lipids and on Microdomains Used in Receptor-Mediated Signaling

    PubMed Central

    Roess, Deborah A.; Smith, Steven M. L.; Winter, Peter; Zhou, Jun; Dou, Ping; Baruah, Bharat; Trujillo, Alejandro M.; Levinger, Nancy E.; Yang, Xioda; Barisas, B. George; Crans, Debbie C.

    2011-01-01

    There is increasing evidence for the involvement of plasma membrane microdomains in insulin receptor function. Moreover, disruption of these structures, which are typically enriched in sphingomyelin and cholesterol, results in insulin resistance. Treatment strategies for insulin resistance include the use of vanadium compounds which have been shown in animal models to enhance insulin responsiveness. One possible mechanism for insulin-enhancing effects might involve direct effects of vanadium compounds on membrane lipid organization. These changes in lipid organization promote the partitioning of insulin receptors and other receptors into membrane microdomains where receptors are optimally functional. To explore this possibility, we have used several strategies involving vanadium complexes such as [VO2dipic]− (pyridin-2,6-dicarboxylatodioxovanadium(V)), decavanadate (V10O286−, V10), BMOV (bis(maltolato)oxovanadium(IV)) and [VO(saltris)]2 (2-salicylideniminato-2-(hydroxymethyl)-1,3-dihydroxypropane-oxovanadium(V)). Our strategies include an evaluation of interactions between vanadium-containing compounds and model lipid systems, an evaluation of the effects of vanadium compounds on lipid fluidity in erythrocyte membranes, and studies of the effects of vanadium-containing compounds on signaling events initiated by receptors known to use membrane microdomains as signaling platforms. PMID:18729092

  9. Effects of vanadium-containing compounds on membrane lipids and on microdomains used in receptor-mediated signaling.

    PubMed

    Roess, Deborah A; Smith, Steven M L; Winter, Peter; Zhou, Jun; Dou, Ping; Baruah, Bharat; Trujillo, Alejandro M; Levinger, Nancy E; Yang, Xioda; Barisas, B George; Crans, Debbie C

    2008-08-01

    There is increasing evidence for the involvement of plasma membrane microdomains in insulin receptor function. Moreover, disruption of these structures, which are typically enriched in sphingomyelin and cholesterol, results in insulin resistance. Treatment strategies for insulin resistance include the use of vanadium (V) compounds which have been shown in animal models to enhance insulin responsiveness. One possible mechanism for insulin-enhancing effects might involve direct effects of V compounds on membrane lipid organization. These changes in lipid organization promote the partitioning of insulin receptors and other receptors into membrane microdomains where receptors are optimally functional. To explore this possibility, we have used several strategies involving V complexes such as [VO(2)(dipic)](-) (pyridin-2,6-dicarboxylatodioxovanadium(V)), decavanadate (V(10)O(28)(6-), V(10)), BMOV (bis(maltolato)oxovanadium(IV)), and [VO(saltris)](2) (2-salicylideniminato-2-(hydroxymethyl)-1,3-dihydroxypropane-oxovanadium(V)). Our strategies include an evaluation of interactions between V-containing compounds and model lipid systems, an evaluation of the effects of V compounds on lipid fluidity in erythrocyte membranes, and studies of the effects of V-containing compounds on signaling events initiated by receptors known to use membrane microdomains as signaling platforms.

  10. Effects of various compounds on lipid peroxidation mediated by detergent-solubilized rat liver NADPH-cytochrome C reductase.

    PubMed

    Kamataki, T; Sugita, O; Naminohira, S; Kitagawa, H

    1978-12-01

    A reconstituted lipid peroxidation system containing NADPH-cytochrome c reductase isolated from detergent-solubilized rat liver microsomes was used to determine the effects of several compounds, including drugs, on the lipid peroxidation activity. EDTA and ferrous ion were essential requirements for reconstitution of the activity. The addition of 1,10-phenanthroline to the system containing both EDTA and ferrous ion further enhanced the activity. Pyrocatecol, thymol, p-aminophenol, imipramine, p-chloromercuribenzoate (PCMB) and alpha-tocopherol exhibited strong inhibition, aniline, N-monomethylaniline, aminopyrine, benzphetamine, SKF 525-A and NADP exhibited moderate inhibition, and phenol, benzoic acid, acetanilide and nicotinamide exhibited less or no inhibition at the concentrations lower than 1000 micron M. Metal ions such as Hg+, Hg2+, Co2+, Cu2+, Mn2+ and U6+ inhibited lipid peroxidation strongly. In addition, Cd2+, St2+ and Ca2+ exhibited less potent to moderate inhibition, and Ba2+ and Mg2+ were without effects on the activity. Among sulfhydryl compounds tested, dithiothreitol inhibited lipid peroxidation to a greater extent than did the other three compounds, glutathione, cysteine and mercaptoethanol.

  11. Direct control of peripheral lipid deposition by CNS GLP-1 receptor signaling is mediated by the sympathetic nervous system and blunted in diet-induced obesity.

    PubMed

    Nogueiras, Ruben; Pérez-Tilve, Diego; Veyrat-Durebex, Christelle; Morgan, Donald A; Varela, Luis; Haynes, William G; Patterson, James T; Disse, Emmanuel; Pfluger, Paul T; López, Miguel; Woods, Stephen C; DiMarchi, Richard; Diéguez, Carlos; Rahmouni, Kamal; Rohner-Jeanrenaud, Françoise; Tschöp, Matthias H

    2009-05-06

    We investigated a possible role of the central glucagon-like peptide (GLP-1) receptor system as an essential brain circuit regulating adiposity through effects on nutrient partitioning and lipid metabolism independent from feeding behavior. Both lean and diet-induced obesity mice were used for our experiments. GLP-1 (7-36) amide was infused in the brain for 2 or 7 d. The expression of key enzymes involved in lipid metabolism was measured by real-time PCR or Western blot. To test the hypothesis that the sympathetic nervous system may be responsible for informing adipocytes about changes in CNS GLP-1 tone, we have performed direct recording of sympathetic nerve activity combined with experiments in genetically manipulated mice lacking beta-adrenergic receptors. Intracerebroventricular infusion of GLP-1 in mice directly and potently decreases lipid storage in white adipose tissue. These effects are independent from nutrient intake. Such CNS control of adipocyte metabolism was found to depend partially on a functional sympathetic nervous system. Furthermore, the effects of CNS GLP-1 on adipocyte metabolism were blunted in diet-induced obese mice. The CNS GLP-1 system decreases fat storage via direct modulation of adipocyte metabolism. This CNS GLP-1 control of adipocyte lipid metabolism appears to be mediated at least in part by the sympathetic nervous system and is independent of parallel changes in food intake and body weight. Importantly, the CNS GLP-1 system loses the capacity to modulate adipocyte metabolism in obese states, suggesting an obesity-induced adipocyte resistance to CNS GLP-1.

  12. Precious-Metal-Free Heteroarylation of Azlactones: Direct Synthesis of α-Pyridyl, α-Substituted Amino Acid Derivatives.

    PubMed

    Johnson, Tarn C; Marsden, Stephen P

    2016-10-21

    A one-pot, three-component synthesis of α-pyridyl, α-substituted amino acid derivatives is described. The key transformation is a direct, precious-metal-free heteroarylation of readily available, amino acid derived azlactones with electrophilically activated pyridine N-oxides. The resulting intermediates can be used directly as efficient acylating agents for a range of nucleophiles, leading to the heteroarylated amino acid derivatives in a single vessel.

  13. Involvement of inducible nitric oxide synthase in hydroxyl radical-mediated lipid peroxidation in streptozotocin-induced diabetes

    PubMed Central

    Stadler, Krisztian; Bonini, Marcelo G.; Dallas, Shannon; Jiang, JinJie; Radi, Rafael; Mason, Ronald P.; Kadiiska, Maria B.

    2008-01-01

    Free radical production is implicated in the pathogenesis of diabetes mellitus, where several pathways and different mechanisms were suggested in the pathophysiology of the complications. In this study, we used electron paramagnetic resonance (EPR) spectroscopy combined with in vivo spin-trapping techniques to investigate the sources and mechanisms of free radical formation in streptozotocin-induced diabetic rats. Free radical production was directly detected in the diabetic bile, which correlated with lipid peroxidation in the liver and kidney. EPR spectra showed the trapping of a lipid-derived radical. Such radicals were demonstrated to be induced by hydroxyl radical through isotope labeling experiments. Multiple enzymes and metabolic pathways were examined as the potential source of the hydroxyl radicals using specific inhibitors. Neither xanthine oxidase, cytochrome P450s, the Fenton reaction, nor macrophage activation were required for the production of radical adducts. Interestingly, inducible nitric oxide synthase (apparently uncoupled) was identified as the major source of radical generation. The specific iNOS inhibitor 1400W as well as l-arginine pretreatment reduced the EPR signals to baseline levels, implicating peroxynitrite as the source of hydroxyl radical production. Applying immunological techniques, we localized iNOS overexpression in the liver and kidney of diabetic animals, which was closely correlated with the lipid radical generation and 4-hydroxynonenal-adducted protein formation, indicating lipid peroxidation. In addition, protein oxidation to protein free radicals occurred in the diabetic target organs. Taken together, our studies support inducible nitric oxide synthase as a significant source of EPR-detectable reactive intermediates, which leads to lipid peroxidation and may contribute to disease progression as well. PMID:18620046

  14. Correlation between chemical structure and rodent repellency of benzoic acid derivatives

    USGS Publications Warehouse

    Fearn, J.E.; DeWitt, J.B.

    1965-01-01

    Sixty-five benzoic acid derivatives were either prepared or obtained from commercial concerns, tested for rat repellency, and their indices of repellency computed. The data from these tests were considered analytically for any correlation between chemical structure and rat repellency. The results suggest a qualitative relationship which is useful in deciding probability of repellency in other compounds.

  15. A novel trans-4-hydroxycinnamic acid derivative from Meyer lemon (Citrus meyeri).

    PubMed

    Miyake, Yoshiaki; Ito, Chihiro; Itoigawa, Masataka

    2012-12-15

    Isolation and structural elucidation of a new trans-4-hydroxycinnamic acid derivative from Meyer lemon (Citrus meyeri hort. ex Y. Tanaka) was carried out. The derivative exhibited the antioxidative activity by ORAC (oxygen radical absorbance capacity) assay and was found in the flavedo and alvedo of Meyer lemon peel.

  16. Proceedings of Symposium Lipid Mediators in Immunology of Shock Held in Copenhagen, Denmark 21-25 July 1986

    DTIC Science & Technology

    1989-07-01

    transmitted to local wound bacteria. New topical agents such as chlorhexidine hydrochloride (which has never been shown to be carried on a plasmid...177 CORONARY STUDIES Methods Domestic pigs (9-12 weeks old) weighing 25-35 kg were sedated with ketamine hydrochloride (20 mg/kg per hr i.v.) and...acetate sodium buffer (M Caroff et al. manuscript in preparation), the Lipid A contained 2 glucosamine residues, 2 phosphate groups, and 5 fatty acids; a

  17. Autonomic nervous system-mediated effects of galanin-like peptide on lipid metabolism in liver and adipose tissue

    PubMed Central

    Hirako, Satoshi; Wada, Nobuhiro; Kageyama, Haruaki; Takenoya, Fumiko; Izumida, Yoshihiko; Kim, Hyounju; Iizuka, Yuzuru; Matsumoto, Akiyo; Okabe, Mai; Kimura, Ai; Suzuki, Mamiko; Yamanaka, Satoru; Shioda, Seiji

    2016-01-01

    Galanin-like peptide (GALP) is a neuropeptide involved in the regulation of feeding behavior and energy metabolism in mammals. While a weight loss effect of GALP has been reported, its effects on lipid metabolism have not been investigated. The aim of this study was to determine if GALP regulates lipid metabolism in liver and adipose tissue via an action on the sympathetic nervous system. The respiratory exchange ratio of mice administered GALP intracerebroventricularly was lower than that of saline-treated animals, and fatty acid oxidation-related gene mRNA levels were increased in the liver. Even though the respiratory exchange ratio was reduced by GALP, this change was not significant when mice were treated with the sympatholytic drug, guanethidine. Lipolysis-related gene mRNA levels were increased in the adipose tissue of GALP-treated mice compared with saline-treated animals. These results show that GALP stimulates fatty acid β-oxidation in liver and lipolysis in adipose tissue, and suggest that the anti-obesity effect of GALP may be due to anorexigenic actions and improvement of lipid metabolism in peripheral tissues via the sympathetic nervous system. PMID:26892462

  18. Integrated systems biology analysis of KSHV latent infection reveals viral induction and reliance on peroxisome mediated lipid metabolism.

    PubMed

    Sychev, Zoi E; Hu, Alex; DiMaio, Terri A; Gitter, Anthony; Camp, Nathan D; Noble, William S; Wolf-Yadlin, Alejandro; Lagunoff, Michael

    2017-03-01

    Kaposi's Sarcoma associated Herpesvirus (KSHV), an oncogenic, human gamma-herpesvirus, is the etiological agent of Kaposi's Sarcoma the most common tumor of AIDS patients world-wide. KSHV is predominantly latent in the main KS tumor cell, the spindle cell, a cell of endothelial origin. KSHV modulates numerous host cell-signaling pathways to activate endothelial cells including major metabolic pathways involved in lipid metabolism. To identify the underlying cellular mechanisms of KSHV alteration of host signaling and endothelial cell activation, we identified changes in the host proteome, phosphoproteome and transcriptome landscape following KSHV infection of endothelial cells. A Steiner forest algorithm was used to integrate the global data sets and, together with transcriptome based predicted transcription factor activity, cellular networks altered by latent KSHV were predicted. Several interesting pathways were identified, including peroxisome biogenesis. To validate the predictions, we showed that KSHV latent infection increases the number of peroxisomes per cell. Additionally, proteins involved in peroxisomal lipid metabolism of very long chain fatty acids, including ABCD3 and ACOX1, are required for the survival of latently infected cells. In summary, novel cellular pathways altered during herpesvirus latency that could not be predicted by a single systems biology platform, were identified by integrated proteomics and transcriptomics data analysis and when correlated with our metabolomics data revealed that peroxisome lipid metabolism is essential for KSHV latent infection of endothelial cells.

  19. Integrated systems biology analysis of KSHV latent infection reveals viral induction and reliance on peroxisome mediated lipid metabolism

    PubMed Central

    Sychev, Zoi E.; Hu, Alex; Lagunoff, Michael

    2017-01-01

    Kaposi’s Sarcoma associated Herpesvirus (KSHV), an oncogenic, human gamma-herpesvirus, is the etiological agent of Kaposi’s Sarcoma the most common tumor of AIDS patients world-wide. KSHV is predominantly latent in the main KS tumor cell, the spindle cell, a cell of endothelial origin. KSHV modulates numerous host cell-signaling pathways to activate endothelial cells including major metabolic pathways involved in lipid metabolism. To identify the underlying cellular mechanisms of KSHV alteration of host signaling and endothelial cell activation, we identified changes in the host proteome, phosphoproteome and transcriptome landscape following KSHV infection of endothelial cells. A Steiner forest algorithm was used to integrate the global data sets and, together with transcriptome based predicted transcription factor activity, cellular networks altered by latent KSHV were predicted. Several interesting pathways were identified, including peroxisome biogenesis. To validate the predictions, we showed that KSHV latent infection increases the number of peroxisomes per cell. Additionally, proteins involved in peroxisomal lipid metabolism of very long chain fatty acids, including ABCD3 and ACOX1, are required for the survival of latently infected cells. In summary, novel cellular pathways altered during herpesvirus latency that could not be predicted by a single systems biology platform, were identified by integrated proteomics and transcriptomics data analysis and when correlated with our metabolomics data revealed that peroxisome lipid metabolism is essential for KSHV latent infection of endothelial cells. PMID:28257516

  20. Pulmonary surfactant protein A and surfactant lipids upregulate IRAK-M, a negative regulator of TLR-mediated inflammation in human macrophages

    PubMed Central

    Nguyen, Huy A.; Rajaram, Murugesan V. S.; Meyer, Douglas A.

    2012-01-01

    Alveolar macrophages (AMs) are exposed to frequent challenges from inhaled particulates and microbes and function as a first line of defense with a highly regulated immune response because of their unique biology as prototypic alternatively activated macrophages. Lung collectins, particularly surfactant protein A (SP-A), contribute to this activation state by fine-tuning the macrophage inflammatory response. During short-term (10 min–2 h) exposure, SP-A's regulation of human macrophage responses occurs through decreased activity of kinases required for proinflammatory cytokine production. However, AMs are continuously exposed to surfactant, and the biochemical pathways underlying long-term reduction of proinflammatory cytokine activity are not known. We investigated the molecular mechanism(s) underlying SP-A- and surfactant lipid-mediated suppression of proinflammatory cytokine production in response to Toll-like receptor (TLR) 4 (TLR4) activation over longer time periods. We found that exposure of human macrophages to SP-A for 6–24 h upregulates expression of IL-1 receptor-associated kinase M (IRAK-M), a negative regulator of TLR-mediated NF-κB activation. Exposure to Survanta, a natural bovine lung extract lacking SP-A, also enhances IRAK-M expression, but at lower magnitude and for a shorter duration than SP-A. Surfactant-mediated upregulation of IRAK-M in macrophages suppresses TLR4-mediated TNF-α and IL-6 production in response to LPS, and IRAK-M knockdown by small interfering RNA reverses this suppression. In contrast to TNF-α and IL-6, the surfactant components upregulate LPS-mediated immunoregulatory IL-10 production, an effect reversed by IRAK-M knockdown. In conclusion, these data identify an important signaling regulator in human macrophages that is used by surfactant to control the long-term alveolar inflammatory response, i.e., enhanced IRAK-M activity. PMID:22886503

  1. The primary role of iron-mediated lipid peroxidation in the differential cytotoxicity caused by two varieties of talc nanoparticles on A549 cells and lipid peroxidation inhibitory effect exerted by ascorbic acid.

    PubMed

    Akhtar, Mohd Javed; Kumar, Sudhir; Murthy, Ramesh Chandra; Ashquin, Mohd; Khan, Mohd Imran; Patil, Govil; Ahmad, Iqbal

    2010-06-01

    Talc particles, the basic ingredient in different kinds of talc-based cosmetic and pharmaceutical products, pose a health risk to pulmonary and ovarian systems due to domestic and occupational exposures. Two types of talc nanoparticles depending on the source of geographical origin - indigenous- and commercial talc nanoparticles were assessed for their potential in vitro toxicity on A(549) cells; along with indigenous conventionally used microtalc particles. Cell viability, determined through live/dead staining and 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, decreased as a function of concentration, origin and size of particles. Both varieties of talc nanoparticles differentially induced lipid peroxidation (LPO), which was correlated with the pattern of lactate dehydrogenase (LDH) leakage, reactive oxygen species (ROS) generation, and glutathione (GSH) depletion. Relatively higher cytotoxicity of indigenous nanotalc could be attributed to its higher content of iron as compared to commercial nanotalc. The known scavenger of ROS, l-ascorbic acid significantly inhibited LPO induction due to talc particles. Data suggest that nanotalc toxicity on A(549) cells was mediated through oxidative stress, wherein role of iron-mediated LPO was much pronounced in differential cytotoxicity.

  2. Total synthesis of the anti-inflammatory and pro-resolving lipid mediator MaR1n-3 DPA utilizing an sp(3) -sp(3) Negishi cross-coupling reaction.

    PubMed

    Tungen, Jørn Eivind; Aursnes, Marius; Dalli, Jesmond; Arnardottir, Hildur; Serhan, Charles Nicholas; Hansen, Trond Vidar

    2014-11-03

    The first total synthesis of the lipid mediator MaR1n-3 DPA (5) has been achieved in 12 % overall yield over 11 steps. The stereoselective preparation of 5 was based on a Pd-catalyzed sp(3) -sp(3) Negishi cross-coupling reaction and a stereocontrolled Evans-Nagao acetate aldol reaction. LC-MS/MS results with synthetic material matched the biologically produced 5. This novel lipid mediator displayed potent pro-resolving properties stimulating macrophage efferocytosis of apoptotic neutrophils.

  3. Glucagon-mediated impairments in hepatic and peripheral tissue nutrient disposal are not aggravated by increased lipid availability

    PubMed Central

    Chen, Sheng-Song; Santomango, Tammy S.; Williams, Phillip E.; Lacy, D. Brooks; McGuinness, Owen P.

    2009-01-01

    Glucose, fat, and glucagon availability are increased in diabetes. The normal response of the liver to chronic increases in glucose availability is to adapt to become a marked consumer of glucose. Yet this fails to occur in diabetes. The aim was to determine whether increased glucagon and lipid interact to impair the adaptation to increased glucose availability. Chronically catheterized well controlled depancreatized conscious dogs (n = 21) received 3 days of continuous parenteral nutrition (TPN) that was either high in glucose [C; 75% nonprotein calories (NPC)] or in lipid (HL; 75% NPC) in the presence or absence of a low dose (one-third basal) chronic intraportal infusion of glucagon (GN; 0.25 ng·kg−1·min−1). During the 3 days of TPN, all groups received the same insulin algorithm; the total amount of glucose infused (GIR) was varied to maintain isoglycemia (∼120 mg/dl). On day 3 of TPN, hepatic metabolism was assessed. Glucose and insulin levels were similar in all groups. GIR was decreased in HL and C + GN (∼30%) and was further decreased in HL + GN (55%). Net hepatic glucose uptake was decreased ∼15% in C + GN, and HL and was decreased ∼50% in HL + GN. Lipid alone or combined with glucagon decreased glucose uptake by peripheral tissues. Despite impairing whole body glucose utilization, HL did not limit whole body energy disposal. In contrast, glucagon suppressed whole body energy disposal irrespective of the diet composition. In summary, failure to appropriately suppress glucagon secretion adds to the dietary fat-induced impairment in both hepatic and peripheral glucose disposal. In addition, unlike increasing the percentage of calories as fat, inappropriate glucagon secretion in the absence of compensatory hyperinsulinemia limits whole body nutrient disposition. PMID:19208853

  4. Acetylsalicylic Acid reduces the severity of dextran sodium sulfate-induced colitis and increases the formation of anti-inflammatory lipid mediators.

    PubMed

    Köhnke, Thomas; Gomolka, Beate; Bilal, Süleyman; Zhou, Xiangzhi; Sun, Yanping; Rothe, Michael; Baumgart, Daniel C; Weylandt, Karsten H

    2013-01-01

    The role of non-steroidal anti-inflammatory drugs in inflammatory bowel disease is controversial, as they have been implicated in disease aggravation. Different from other cyclooxygenase inhibitors, acetylsalicylic acid (ASA) enhances the formation of anti-inflammatory and proresolution lipoxins derived from arachidonic acid as well as resolvins from omega-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA). In this study, we examined the effect of ASA on murine dextran sodium sulfate colitis. A mouse magnetic resonance imaging (MRI) protocol and post mortem assessment were used to assess disease severity, and lipid metabolites were measured using liquid chromatography-coupled tandem mass spectrometry. Decreased colitis activity was demonstrated by phenotype and MRI assessment in mice treated with ASA, and confirmed in postmortem analysis. Analysis of lipid mediators showed sustained formation of lipoxin A4 and an increase of DHA-derived 17-hydroxydocosahexaenoic acid (17-HDHA) after treatment with ASA. Furthermore, in vitro experiments in RAW264.7 murine macrophages demonstrated significantly increased phagocytosis activity after incubation with 17-HDHA, supporting its proresolution effect. These results show a protective effect of ASA in a murine colitis model and could give a rationale for a careful reassessment of ASA therapy in patients with inflammatory bowel disease and particularly ulcerative colitis, possibly combined with DHA supplementation.

  5. Phospholipid-modified polyethylenimine-based nanopreparations for siRNA–mediated gene silencing: Implications for transfection and the role of lipid components

    PubMed Central

    Navarro, Gemma; Essex, Sean; Sawant, Rupa R.; Biswas, Swati; Nagesha, Dattatri; Sridhar, Srinivas; de ILarduya, Conchita Tros; Torchilin, Vladimir P.

    2013-01-01

    The clinical application of gene silencing mediated by small interfering RNA (siRNA) has been limited by the lack of efficient and safe carriers. Phospholipid modification of low molecular weight polyethylenimine (PEI 1.8 kDa) dramatically increased its gene down-regulation capacity while keeping cytotoxicity levels low. The silencing efficacy was highly dependent on the nature of the lipid grafted to PEI and the polymer/siRNA ratio employed. Phosphoethanolamine (DOPE and DPPE) and phosphocholine (PC) conjugation did not change the physicochemical properties and siRNA binding capacity of PEI complexes but had a large impact on their transfection and ability to downregulate Green Fluorescent Protein (GFP) expression (60%, 30% and 5% decrease of GFP expression respectively). We found that the micelle-forming structure of DOPE and DPPE-PEI dramatically changed PEI’s interaction with cell membranes and played a key role in promoting PEI 1.8 kDa transfection, completely ineffective in the absence of the lipid modification. PMID:23928214

  6. Soluble Glucan Is Internalized and Trafficked to the Golgi Apparatus in Macrophages via a Clathrin-Mediated, Lipid Raft-Regulated Mechanism

    PubMed Central

    Goldman, Matthew P.; Kalbfleisch, John H.; Williams, David L.

    2012-01-01

    Glucans are natural product carbohydrates that stimulate immunity. Glucans are internalized by the pattern recognition receptor, Dectin-1. Glucans were thought to be trafficked to phagolysosomes, but this is unproven. We examined the internalization and trafficking of soluble glucans in macrophages. Incubation of macrophages with glucan resulted in internalization of Dectin-1 and glucan. Inhibition of clathrin blocked internalization of the Dectin-1/glucan complex. Lipid raft depletion resulted in decreased Dectin levels and glucan uptake. Once internalized, glucans colocalized with early endosomes at 0 to 15 min, with the Golgi apparatus at 15 min to 24 h, and with Dectin-1 immediately (0 h) and again later (15 min-24 h). Glucans did not colocalize with lysosomes at any time interval examined. We conclude that the internalization of Dectin-1/glucan complexes in macrophages is mediated by clathrin and negatively regulated by lipid rafts and/or caveolin-1. Upon internalization, soluble glucans are trafficked via endosomes to the Golgi apparatus, not lysosomes. PMID:22700434

  7. Lipid Peroxide-Derived Short-Chain Carbonyls Mediate Hydrogen Peroxide-Induced and Salt-Induced Programmed Cell Death in Plants.

    PubMed

    Biswas, Md Sanaullah; Mano, Jun'ichi

    2015-07-01

    Lipid peroxide-derived toxic carbonyl compounds (oxylipin carbonyls), produced downstream of reactive oxygen species (ROS), were recently revealed to mediate abiotic stress-induced damage of plants. Here, we investigated how oxylipin carbonyls cause cell death. When tobacco (Nicotiana tabacum) Bright Yellow-2 (BY-2) cells were exposed to hydrogen peroxide, several species of short-chain oxylipin carbonyls [i.e. 4-hydroxy-(E)-2-nonenal and acrolein] accumulated and the cells underwent programmed cell death (PCD), as judged based on DNA fragmentation, an increase in terminal deoxynucleotidyl transferase dUTP nick end labeling-positive nuclei, and cytoplasm retraction. These oxylipin carbonyls caused PCD in BY-2 cells and roots of tobacco and Arabidopsis (Arabidopsis thaliana). To test the possibility that oxylipin carbonyls mediate an oxidative signal to cause PCD, we performed pharmacological and genetic experiments. Carnosine and hydralazine, having distinct chemistry for scavenging carbonyls, significantly suppressed the increase in oxylipin carbonyls and blocked PCD in BY-2 cells and Arabidopsis roots, but they did not affect the levels of ROS and lipid peroxides. A transgenic tobacco line that overproduces 2-alkenal reductase, an Arabidopsis enzyme to detoxify α,β-unsaturated carbonyls, suffered less PCD in root epidermis after hydrogen peroxide or salt treatment than did the wild type, whereas the ROS level increases due to the stress treatments were not different between the lines. From these results, we conclude that oxylipin carbonyls are involved in the PCD process in oxidatively stressed cells. Our comparison of the ability of distinct carbonyls to induce PCD in BY-2 cells revealed that acrolein and 4-hydroxy-(E)-2-nonenal are the most potent carbonyls. The physiological relevance and possible mechanisms of the carbonyl-induced PCD are discussed.

  8. Supramolecular chiral host-guest nanoarchitecture induced by the selective assembly of barbituric acid derivative enantiomers

    NASA Astrophysics Data System (ADS)

    Sun, Xiaonan; Silly, Fabien; Maurel, Francois; Dong, Changzhi

    2016-10-01

    Barbituric acid derivatives are prochiral molecules, i.e. they are chiral upon adsorption on surfaces. Scanning tunneling microscopy reveals that barbituric acid derivatives self-assemble into a chiral guest-host supramolecular architecture at the solid-liquid interface on graphite. The host nanoarchitecture has a sophisticated wavy shape pattern and paired guest molecules are nested insides the cavities of the host structure. Each unit cell of the host structure is composed of both enantiomers with a ratio of 1:1. Furthermore, the wavy patterns of the nanoarchitecture are formed from alternative appearance of left- and right-handed chiral building blocks, which makes the network heterochiral. The functional guest-host nanoarchitecture is the result of two-dimensional chiral amplification from single enantiomers to organizational heterochiral supramolecular self-assembly.

  9. Ellagic acid derivatives from Syzygium cumini stem bark: investigation of their antiplasmodial activity.

    PubMed

    Simões-Pires, Claudia A; Vargas, Sandra; Marston, Andrew; Ioset, Jean-Robert; Paulo, Marçal Q; Matheeussen, An; Maes, Louis

    2009-10-01

    Bioguided fractionation of Syzygium cumini (Myrtaceae) bark decoction for antiplasmodial activity was performed, leading to the isolation of three known ellagic acid derivatives (ellagic acid, ellagic acid 4-O-alpha-L-2"-acetylrhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-L-rhamnopyranoside), as well as the new derivative 3-O-methylellagic acid 3'-O-beta-D-glucopyranoside. Activity investigation was based on the reduction of P. falciparum (PfK1) parasitaemia in vitro and the inhibition of beta-hematin formation, a known mechanism of action of some antimalarial drugs. Among the investigated ellagic acid derivatives, only ellagic acid was able to reduce P. falciparum parasitaemia in vitro and inhibit beta-hematin formation, suggesting that free hydroxyl groups are necessary for activity within this class of compounds.

  10. Synthesis and preliminary biological evaluations of (+)-isocampholenic acid-derived amides.

    PubMed

    Grošelj, Uroš; Golobič, Amalija; Knez, Damijan; Hrast, Martina; Gobec, Stanislav; Ričko, Sebastijan; Svete, Jurij

    2016-08-01

    The synthesis of two novel (+)-isocampholenic acid-derived amines has been realized starting from commercially available (1S)-(+)-10-camphorsulfonic acid. The novel amines as well as (+)-isocampholenic acid have been used as building blocks in the construction of a library of amides using various aliphatic, aromatic, and amino acid-derived coupling partners using BPC and CDI as activating agents. Amide derivatives have been assayed against several enzymes that hold potential for the development of new drugs to battle bacterial infections and Alzheimer's disease. Compounds 20c and 20e showed promising selective sub-micromolar inhibition of human butyrylcholinesterase [Formula: see text] ([Formula: see text] values [Formula: see text] and [Formula: see text], respectively).

  11. Quinic acid derivatives from Pimpinella brachycarpa exert anti-neuroinflammatory activity in lipopolysaccharide-induced microglia.

    PubMed

    Lee, Seung Young; Moon, Eunjung; Kim, Sun Yeou; Lee, Kang Ro

    2013-04-01

    Five new quinic acid derivatives (1-5), together with 10 known quinic acid derivatives (6-15), were isolated from the MeOH extract of Pimpinella brachycarpa (Umbelliferae). Their structures were established on the basis of spectroscopic analyses including extensive 2D NMR studies (COSY, HMQC and HMBC). Isolated compounds 1-15 were evaluated for their inhibitory activities on nitric oxide (NO) production in an activated murine microglial cell line. Compounds 2, 3, 8 and 11 significantly inhibited NO production without high cell toxicity in lipopolysaccharide (LPS)-activated BV-2 cells, a microglia cell line (IC50=4.66, 12.52, 9.04 and 12.11 μM, respectively).

  12. Revealing the mechanism of passive transport in lipid bilayers via phonon-mediated nanometre-scale density fluctuations

    DOE PAGES

    Zhernenkov, Mikhail; Bolmatov, Dima; Soloviov, Dmitry; ...

    2016-05-12

    The passive transport of molecules through a cell membrane relies on thermal motions of the lipids. However, the nature of transmembrane transport and the precise mechanism remain elusive and call for a comprehensive study of phonon excitations. Here we report a high resolution inelastic X-ray scattering study of the in-plane phonon excitations in 1,2-dipalmitoyl-sn-glycero-3-phosphocholine above and below the main transition temperature. In the gel phase, for the first time, we observe low-frequency transverse modes, which exhibit a phonon gap when the lipid transitions into the fluid phase. We argue that the phonon gap signifies the formation of short-lived nanometre-scale lipidmore » clusters and transient pores, which facilitate the passive molecular transport across the bilayer plane. Finally, our findings suggest that the phononic motion of the hydrocarbon tails provides an effective mechanism of passive transport, and illustrate the importance of the collective dynamics of biomembranes.« less

  13. General Detoxification and Stress Responses Are Mediated by Oxidized Lipids through TGA Transcription Factors in Arabidopsis[W

    PubMed Central

    Mueller, Stefan; Hilbert, Beate; Dueckershoff, Katharina; Roitsch, Thomas; Krischke, Markus; Mueller, Martin J.; Berger, Susanne

    2008-01-01

    12-oxo-phytodienoic acid and several phytoprostanes are cyclopentenone oxylipins that are formed via the enzymatic jasmonate pathway and a nonenzymatic, free radical–catalyzed pathway, respectively. Both types of cyclopentenone oxylipins induce the expression of genes related to detoxification, stress responses, and secondary metabolism, a profile clearly distinct from that of the cyclopentanone jasmonic acid. Microarray analyses revealed that 60% of the induction by phytoprostanes and 30% of the induction by 12-oxo-phytodienoic acid was dependent on the TGA transcription factors TGA2, TGA5, and TGA6. Moreover, treatment with phytoprostanes and 12-oxo-phytodienoic acid inhibited cell division and root growth, a property also shared by jasmonic acid. Besides being potent signals, cyclopentenones and other lipid peroxidation products are reactive electrophiles that can covalently bind to and damage proteins. To this end, we show that at least two of the induced detoxification enzymes efficiently metabolize cyclopentenones in vitro. Accumulation of two of these metabolites was detectable during Pseudomonas infection. The cyclopentenone oxylipin gene induction profile resembles the defense response induced by a variety of lipophilic xenobiotics. Hence, oxidized lipids may activate chemosensory mechanisms of a general broad-spectrum detoxification network involving TGA transcription factors. PMID:18334669

  14. Novel long chain fatty acid derivatives of quercetin-3-O-glucoside reduce cytotoxicity induced by cigarette smoke toxicants in human fetal lung fibroblasts.

    PubMed

    Warnakulasuriya, Sumudu N; Ziaullah; Rupasinghe, H P Vasantha

    2016-06-15

    Smoking has become a global health concern due to its association with many disease conditions, such as chronic obstructive pulmonary disease (COPD), cardiovascular diseases (CVD) and cancer. Flavonoids are plant polyphenolic compounds, studied extensively for their antioxidant, anti-inflammatory, and anti-carcinogenic properties. Quercetin-3-O-glucoside (Q3G) is a flavonoid which is widely found in plants. Six novel long chain fatty acid [stearic acid, oleic acid, linoleic acid, α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] derivatives of Q3G were evaluated for their potential in protecting human lung fibroblasts against cytotoxicity induced by selected cigarette smoke toxicants: 4-(methylnitrosoamino)-1-(3-pyridinyl)-1-butanone (NNK), benzo-α-pyrene (BaP), nicotine and chromium (Cr[VI]). Nicotine and Cr[VI] induced toxicity in fibroblasts and reduced the percentage of viable cells, while BaP and NNK did not affect cell viability. The fatty acid derivatives of Q3G provided protection against nicotine- and Cr[VI]-induced cell death and membrane lipid peroxidation. Based on the evaluation of inflammatory markers of cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2), the fatty acid derivatives of Q3G were found to be effective in lowering the inflammatory response. Overall, these novel fatty acid esters of Q3G warrant further investigation as potential cytoprotective agents.

  15. Synthesis of new kojic acid based unnatural α-amino acid derivatives.

    PubMed

    Balakrishna, C; Payili, Nagaraju; Yennam, Satyanarayana; Devi, P Uma; Behera, Manoranjan

    2015-11-01

    An efficient method for the preparation of kojic acid based α-amino acid derivatives by alkylation of glycinate schiff base with bromokojic acids have been described. Using this method, mono as well as di alkylated kojic acid-amino acid conjugates have been prepared. This is the first synthesis of C-linked kojic acid-amino acid conjugate where kojic acid is directly linked to amino acid through a C-C bond.

  16. Synthesis of sulfonic acid derivatives by oxidative deprotection of thiols using tert-butyl hypochlorite.

    PubMed

    Joyard, Yoann; Papamicaël, Cyril; Bohn, Pierre; Bischoff, Laurent

    2013-05-03

    Starting from alkyl halides or Michael acceptors, thioacetates were prepared in situ and further treated with t-BuOCl, affording the corresponding sulfonyl chlorides which were trapped with nucleophiles such as water, alcohol, or amines. The three steps can be achieved in a one-pot procedure. Oxidative deprotection also proved to be efficient with S-trityl and S-tert-butyl groups, making it a convenient route toward cysteic acid derivatives.

  17. Production of Fatty Acid-derived valuable chemicals in synthetic microbes.

    PubMed

    Yu, Ai-Qun; Pratomo Juwono, Nina Kurniasih; Leong, Susanna Su Jan; Chang, Matthew Wook

    2014-01-01

    Fatty acid derivatives, such as hydroxy fatty acids, fatty alcohols, fatty acid methyl/ethyl esters, and fatty alka(e)nes, have a wide range of industrial applications including plastics, lubricants, and fuels. Currently, these chemicals are obtained mainly through chemical synthesis, which is complex and costly, and their availability from natural biological sources is extremely limited. Metabolic engineering of microorganisms has provided a platform for effective production of these valuable biochemicals. Notably, synthetic biology-based metabolic engineering strategies have been extensively applied to refactor microorganisms for improved biochemical production. Here, we reviewed: (i) the current status of metabolic engineering of microbes that produce fatty acid-derived valuable chemicals, and (ii) the recent progress of synthetic biology approaches that assist metabolic engineering, such as mRNA secondary structure engineering, sensor-regulator system, regulatable expression system, ultrasensitive input/output control system, and computer science-based design of complex gene circuits. Furthermore, key challenges and strategies were discussed. Finally, we concluded that synthetic biology provides useful metabolic engineering strategies for economically viable production of fatty acid-derived valuable chemicals in engineered microbes.

  18. Monoterpene-based chiral β-amino acid derivatives prepared from natural sources: syntheses and applications.

    PubMed

    Szakonyi, Zsolt; Fülöp, Ferenc

    2011-08-01

    Natural monoterpenes have proved to be good starting materials for the synthesis of β-amino acid derivatives. In the past decade, a number of well-known synthetic procedures have been applied for the preparation of monoterpene-based β-amino acid derivatives, e.g. from β-lactams via the 1,2-dipolar cycloaddition of chlorosulfonyl isocyanate to commercial or readily available monoterpenes [e.g. (+)- and (-)-α- or δ-pinene, (+)-3- and 2-carene, (+)- and (-)-apopinene], the conjugate addition of amides to monoterpene-based α,β-unsaturated esters or the transformations of (-)-cis-pinonoic acid prepared by the oxidative cleavage of (+)- and (-)-verbenone. β-Amino acid derivatives are excellent building blocks for versatile transformations, e.g. multicomponent reactions resulting in β-lactams, syntheses of 1,3-heterocycles and diaminopyrimidine derivatives or the formation of peptides containing an H12 helix. 1,3-Amino alcohol derivatives prepared from β-amino esters have been applied as chiral catalysts in enantioselective transformations. Several of these compounds are of noteworthy pharmacological importance, such as tyrosine kinase Axl inhibitor diaminopyrimidine-coupled β-aminocarboxamides, MDR inhibitor thiourea derivatives of β-amino esters or 2-imino-1,3-oxazines, which exhibit marked growth inhibitory activity on multiple cancer cell lines. The present review summarizes recent developments relating to the syntheses, applications and pharmaceutical importance of monoterpene-based β-amino acids and their derivatives.

  19. Production of Fatty Acid-Derived Valuable Chemicals in Synthetic Microbes

    PubMed Central

    Yu, Ai-Qun; Pratomo Juwono, Nina Kurniasih; Leong, Susanna Su Jan; Chang, Matthew Wook

    2014-01-01

    Fatty acid derivatives, such as hydroxy fatty acids, fatty alcohols, fatty acid methyl/ethyl esters, and fatty alka(e)nes, have a wide range of industrial applications including plastics, lubricants, and fuels. Currently, these chemicals are obtained mainly through chemical synthesis, which is complex and costly, and their availability from natural biological sources is extremely limited. Metabolic engineering of microorganisms has provided a platform for effective production of these valuable biochemicals. Notably, synthetic biology-based metabolic engineering strategies have been extensively applied to refactor microorganisms for improved biochemical production. Here, we reviewed: (i) the current status of metabolic engineering of microbes that produce fatty acid-derived valuable chemicals, and (ii) the recent progress of synthetic biology approaches that assist metabolic engineering, such as mRNA secondary structure engineering, sensor-regulator system, regulatable expression system, ultrasensitive input/output control system, and computer science-based design of complex gene circuits. Furthermore, key challenges and strategies were discussed. Finally, we concluded that synthetic biology provides useful metabolic engineering strategies for economically viable production of fatty acid-derived valuable chemicals in engineered microbes. PMID:25566540

  20. Induction of hepatocyte growth factor production in human dermal fibroblasts by caffeic acid derivatives.

    PubMed

    Kurisu, Manami; Nakasone, Rie; Miyamae, Yusaku; Matsuura, Daisuke; Kanatani, Hirotoshi; Yano, Shingo; Shigemori, Hideyuki

    2013-01-01

    Hepatocyte growth factor (HGF) has mitogenic, motogenic, and morphogenic activities in epithelial cells. Induction of HGF production may be involved in organ regeneration, wound healing and embryogenesis. In this study, we examined the effects of caffeic acid derivatives including 4,5-di-O-caffeoylquinic acid (1) and acteoside (2) on HGF production in Neonatal Normal Human Dermal Fibroblasts (NHDF). Both 4,5-di-O-caffeoylquinic acid (1) and acteoside (2) significantly induced HGF production dose-dependent manner. To know the important substructure for HGF production activity, we next investigated the effect of the partial structure of these caffeic acid derivatives. From the results, caffeic acid (3) showed strong activity on the promotion of HGF production, while hydroxytyrosol (4) and quinic acid (5) didn't show any activity. Our findings suggest that the caffeoyl moiety of caffeic acid derivatives is essential for accelerated production of HGF. The compound which has the caffeoyl moiety may be useful for the treatment of some intractable organ disease.

  1. Pd(II)-catalysed meta-C–H functionalizations of benzoic acid derivatives

    PubMed Central

    Li, Shangda; Cai, Lei; Ji, Huafang; Yang, Long; Li, Gang

    2016-01-01

    Benzoic acids are highly important structural motifs in drug molecules and natural products. Selective C–H bond functionalization of benzoic acids will provide synthetically useful tools for step-economical organic synthesis. Although direct ortho-C–H functionalizations of benzoic acids or their derivatives have been intensely studied, the ability to activate meta-C–H bond of benzoic acids or their derivatives in a general manner via transition-metal catalysis has been largely unsuccessful. Although chelation-assisted meta-C–H functionalization of electron-rich arenes was reported, chelation-assisted meta-C–H activation of electron-poor arenes such as benzoic acid derivatives remains a formidable challenge. Herein, we report a general protocol for meta-C–H olefination of benzoic acid derivatives using a nitrile-based sulfonamide template. A broad range of benzoic acid derivatives are meta-selectively olefinated using molecular oxygen as the terminal oxidant. The meta-C–H acetoxylation, product of which is further transformed at the meta-position, is also reported. PMID:26813919

  2. Endoplasmic reticulum stress and dysregulation of calcium homeostasis mediate Cu-induced alteration in hepatic lipid metabolism of javelin goby Synechogobius hasta.

    PubMed

    Song, Yu-Feng; Huang, Chao; Shi, Xi; Pan, Ya-Xiong; Liu, Xu; Luo, Zhi

    2016-06-01

    The present study was conducted to investigate the effect of Cu exposure on endoplasmic reticulum (ER) stress and Ca(2+) homeostasis, and also explore the underlying mechanism of the ER stress and Ca(2+) homeostasis in the Cu-induced change of hepatic lipid metabolism in javelin goby Synechogobius hasta. To this end, four experiments were conducted. In experiment 1, the full-length cDNA sequences of two ER molecular chaperones [glucose-regulated protein 78 (GRP78) and calreticulin (CRT)] and three ER stress sensors [PKR-like ER kinase (PERK), inositol requiring enzyme (IRE)-1α, and activating transcription factor (ATF)-6α] cDNAs were firstly characterized from S. hasta. The predicted amino acid sequences for the S. hasta GRP78, CRT, PERK, IRE-1α and ATF-6α revealed that the proteins contained all of the structural features characteristic in other species. mRNAs of the five genes were expressed in various tissues, but their mRNA levels varied among tissues. In experiment 2, S. hasta were exposed to four waterborne Cu concentrations (control, 19μg/l, 38μg/l, and 57μg/l, respectively) for 60days. Cu exposure evoked ER stress in liver of S. hasta in a time- and concentration-course change. In experiment 3, specific inhibitors, 2-aminoethyldiphenyl borate (2-APB) and dantrolene, were used to explore whether Ca(2+) release from ER was involved in the Cu-induced ER stress change. Dantrolene and 2-APB prevented Cu-induced intracellular Ca(2+) elevation, which demonstrated the release of Ca(2+) from the ER was mediated by both RyR and IP3R. In experiment 4, a chemical chaperone, 4-phenyl butyric acid (4-PBA), was used to demonstrate whether Cu-induced alteration in lipid metabolism was suppressed through the attenuation of ER stress. Cu exposure evoked ER stress and sterol-regulator element-binding protein-1c (SREBP-1c) activation in hepatocytes of S. hasta, resulting in dysregulation of hepatic lipid metabolism. 4-PBA attenuated the Cu-induced elevation of m

  3. CD169+ MACROPHAGES PRESENT LIPID ANTIGENS TO MEDIATE EARLY ACTIVATION OF INVARIANT NKT CELLS IN LYMPH NODES

    PubMed Central

    Barral, Patricia; Polzella, Paolo; Bruckbauer, Andreas; van Rooijen, Nico; Besra, Gurdyal S.; Cerundolo, Vincenzo; Batista, Facundo D.

    2010-01-01

    Invariant NKT (iNKT) cells are involved in host defence against microbial infections. While it is known that iNKT cells recognize glycolipids presented by CD1d, how and where they encounter antigen in vivo remains unclear. We used multi-photon microscopy to visualize the dynamics and activation of iNKT cells in lymph nodes. Following antigen administration, iNKT cells become confined in a CD1d-dependent manner in close proximity to subcapsular sinus CD169+ macrophages. These macrophages retain, internalize and present lipid antigen, and are required for iNKT cell activation, cytokine production and expansion. Thus, CD169+ macrophages can act as bona fide antigen presenting cells controlling early iNKT cell activation and favouring fast initiation of immune responses. PMID:20228797

  4. CD169(+) macrophages present lipid antigens to mediate early activation of iNKT cells in lymph nodes.

    PubMed

    Barral, Patricia; Polzella, Paolo; Bruckbauer, Andreas; van Rooijen, Nico; Besra, Gurdyal S; Cerundolo, Vincenzo; Batista, Facundo D

    2010-04-01

    Invariant natural killer T cells (iNKT cells) are involved in the host defense against microbial infection. Although it is known that iNKT cells recognize glycolipids presented by CD1d, how and where they encounter antigen in vivo remains unclear. Here we used multiphoton microscopy to visualize the dynamics and activation of iNKT cells in lymph nodes. After antigen administration, iNKT cells became confined in a CD1d-dependent manner in close proximity to subcapsular sinus CD169(+) macrophages. These macrophages retained, internalized and presented lipid antigen and were required for iNKT cell activation, cytokine production and population expansion. Thus, CD169(+) macrophages can act as true antigen-presenting cells controlling early iNKT cell activation and favoring the fast initiation of immune responses.

  5. Peptidoglycan-mediated IL-8 expression in human alveolar type II epithelial cells requires lipid raft formation and MAPK activation.

    PubMed

    Cheon, In Su; Woo, Sang Su; Kang, Seok-Seong; Im, Jintaek; Yun, Cheol-Heui; Chung, Dae Kyun; Park, Dong Ki; Han, Seung Hyun

    2008-03-01

    Staphylococcus aureus, a major sepsis-causing Gram-positive bacterium, invades pulmonary epithelial cells and causes lung diseases. In the lung, alveolar type II epithelial cells play an important role in innate immunity by secreting chemokines and antimicrobial peptides upon bacterial infection whereas type I cells mainly function in gas-exchange. In this study, we investigated the ability of S. aureus peptidoglycan (PGN) to induce expression of a chemokine, IL-8, in a human alveolar type II epithelial cell line, A549. PGN induces IL-8 mRNA and protein expression in a dose- and time-dependent manner. Supplementation of soluble CD14 further enhanced the PGN-induced IL-8 expression. Interestingly, PGN-induced IL-8 expression was inhibited by nystatin, a specific inhibitor for lipid rafts, but not by chlorpromazine, a specific inhibitor for clathrin-coated pits. Furthermore, PGN-induced IL-8 expression was attenuated by inhibitors for MAP kinases such as ERK, p38 kinase, and JNK/SAPK, whereas no inhibitory effect was observed by inhibitors for reactive oxygen species or protein kinase C. Electrophoretic mobility shift assay demonstrates that PGN increased the DNA binding of the transcription factors, AP-1 and NF-kappaB while minimally, NF-IL6, all of which are involved in the transcription of IL-8. Taken together, these results suggest that PGN induces IL-8 expression in a CD14-enhanced manner in human alveolar type II epithelial cells, through the formation of lipid rafts and the activation of MAP kinases, which ultimately leads to activation of AP-1, NF-kappaB, and NF-IL6.

  6. High content analysis platform for optimization of lipid mediated CRISPR-Cas9 delivery strategies in human cells

    PubMed Central

    Steyer, Benjamin; Carlson-Stevermer, Jared; Angenent-Mari, Nicolas; Khalil, Andrew; Harkness, Ty; Saha, Krishanu

    2016-01-01

    Non-viral gene-editing of human cells using the CRISPR-Cas9 system requires optimized delivery of multiple components. Both the Cas9 endonuclease and a single guide RNA, that defines the genomic target, need to be present and co-localized within the nucleus for efficient gene-editing to occur. This work describes a new high-throughput screening platform for the optimization of CRISPR-Cas9 delivery strategies. By exploiting high content image analysis and microcontact printed plates, multi-parametric gene-editing outcome data from hundreds to thousands of isolated cell populations can be screened simultaneously. Employing this platform, we systematically screened four commercially available cationic lipid transfection materials with a range of RNAs encoding the CRISPR-Cas9 system. Analysis of Cas9 expression and editing of a fluorescent mCherry reporter transgene within human embryonic kidney cells was monitored over several days after transfection. Design of experiments analysis enabled rigorous evaluation of delivery materials and RNA concentration conditions. The results of this analysis indicated that the concentration and identity of transfection material have significantly greater effect on gene-editing than ratio or total amount of RNA. Cell subpopulation analysis on microcontact printed plates, further revealed that low cell number and high Cas9 expression, 24 hours after CRISPR-Cas9 delivery, were strong predictors of gene-editing outcomes. These results suggest design principles for the development of materials and transfection strategies with lipid-based materials. This platform could be applied to rapidly optimize materials for gene-editing in a variety of cell/tissue types in order to advance genomic medicine, regenerative biology and drug discovery. PMID:26747759

  7. A conserved, lipid-mediated sorting mechanism of yeast Ist2 and mammalian STIM proteins to the peripheral ER.

    PubMed

    Ercan, Ebru; Momburg, Frank; Engel, Ulrike; Temmerman, Koen; Nickel, Walter; Seedorf, Matthias

    2009-12-01

    Sorting of yeast Ist2 to the plasma membrane (PM) or the cortical endoplasmic reticulum (ER) requires a cortical sorting signal (CSS(Ist2)) that interacts with lipids including phosphatidylinositol-4,5-bisphosphate (PI(4,5)P(2)) at the PM. Here, we show that the expression of Ist2 in mammalian cells resulted in a peripheral patch-like localization without any detection of Ist2 at the cell surface. Attached to C-termini of mammalian integral membrane proteins, the CSS(Ist2) targeted these proteins to PM-associated domains of the ER and abolished trafficking via the classical secretory pathway. The interaction of integral membrane proteins with PI(4,5)P(2) at the PM created ER-PM contacts. This process is similar to the regulated coupling of ER domains to the PM via stromal interaction molecule (STIM) proteins during store-operated Ca(2+) entry (SOCE). The CSS(Ist2) and the C-terminus of the ER-located Ca(2+) sensor STIM2 were sufficient to bind PI(4,5)P(2) and PI(3,4,5)P(3) at the PM, showing that an evolutionarily conserved mechanism is involved in the sorting of integral membrane proteins to PM-associated domains of the ER. Yeast Ist2 and STIM2 share a common basic and amphipathic signal at their extreme C-termini. STIM1 showed binding preference for liposomes containing PI(4,5)P(2), suggesting a specific contribution of lipids to the recruitment of ER domains to the PM during SOCE.

  8. Pathway Markers for Pro-resolving Lipid Mediators in Maternal and Umbilical Cord Blood: A Secondary Analysis of the Mothers, Omega-3, and Mental Health Study

    PubMed Central

    Mozurkewich, Ellen L.; Greenwood, Matthew; Clinton, Chelsea; Berman, Deborah; Romero, Vivian; Djuric, Zora; Qualls, Clifford; Gronert, Karsten

    2016-01-01

    The omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are precursors to immune regulatory and specialized pro-resolving mediators (SPM) of inflammation termed resolvins, maresins, and protectins. Evidence for lipid mediator formation in vivo can be gained through evaluation of their 5-lipoxygenase (LOX) and 15-LOX metabolic pathway precursors and downstream metabolites. We performed a secondary blood sample analysis from 60 participants in the Mothers, Omega-3, and Mental Health study to determine whether SPM and SPM precursors are augmented by dietary EPA- and DHA-rich fish oil supplementation compared to soy oil placebo. We also aimed to study whether SPM and their precursors differ in early and late pregnancy or between maternal and umbilical cord blood. We found that compared to placebo supplementation, EPA- and DHA-rich fish oil supplementation increased SPM precursor 17-hydroxy docosahexaenoic acid (17-HDHA) concentrations in maternal and umbilical cord blood (P = 0.02). We found that the D-series resolvin pathway marker 17-HDHA increased significantly between enrollment and late pregnancy (P = 0.049). Levels of both 14-HDHA, a maresin pathway marker, and 17-HDHA were significantly greater in umbilical cord blood than in maternal blood (P < 0.001, both). PMID:27656142

  9. [Effectiveness of 3-hydroxypyridine and succinic acid derivatives in complex treatment of primary open-angle glaucoma].

    PubMed

    Volchegorskiĭ, I A; Tur, E V; Soliannikova, O V; Rykun, V S; Sumina, M S; Dmitrienko, V N; Berdnikova, E V

    2012-01-01

    Prospective, placebo-controlled, single-blind, randomized clinical investigation of the influence of domestic 3-hydroxypyridine and succinic acid derivatives (emoxipin, reamberin, mexidol) on the effectiveness of a complex treatment of primary open-angle glaucoma (POAG) has been performed in a group of patients. It is established that intravenous infusion of 3-hydroxypyridine derivatives (emoxipin and mexidol) for two weeks, beginning 14 days after the start of POAG treatment, produced a retinoprotective action, with three months postponed changes in the central retinal artery (CRA) blood velocity. The retinoprotective effect of emoxipin (single dose, 150 mg) was manifested by reduction in the horizontal size of blind spot in two weeks, with the subsequent reduction of the CRA end-diastolic blood velocity observed three months after finish of the infusion therapy. The administration of mexidol (single dose, 300 mg) after 14 days of treatment led to widening of the summarized field of vision (test-object square, 16 mm), accompanied by a decrease in the electrosensitivity threshold of the optic nerve and the intensity of POAG-associated hypothymia. All indices of CRA blood velocity increased three months after termination of mexidol infusions. Reamberin (single dose, 400 ml 1,5% solution of reamberine, containing polyelectrolyte and meglumine succinate mixture) did not show retinoprotective action, but caused proatherogenic changes of blood lipids and 3 months postponed CRA end-diastolic blood velocity increase. The effect of mexidol (which is a derivative of both 3- hydroxypyridine and succinic acid) exceeds that of separate 3-hydroxypyridine (emoxipin) and succinic acid (reamberin) derivatives in the degree of retinoprotection and positive effect on the optic nerve condition and mood of POAG patients.

  10. A Copper-Mediated Disulfiram-Loaded pH-Triggered PEG-Shedding TAT Peptide-Modified Lipid Nanocapsules for Use in Tumor Therapy.

    PubMed

    Zhang, Ling; Tian, Bin; Li, Yi; Lei, Tian; Meng, Jia; Yang, Liu; Zhang, Yan; Chen, Fen; Zhang, Haotian; Xu, Hui; Zhang, Yu; Tang, Xing

    2015-11-18

    Disulfiram, which exhibits marked tumor inhibition mediated by copper, was encapsulated in lipid nanocapsules modified with TAT peptide (TATp) and pH-triggered sheddable PEG to target cancer cells on the basis of tumor environmental specificity. PEG-shedding lipid nanocapsules (S-LNCs) were fabricated from LNCs by decorating short PEG chains with TATp (HS-PEG(1k)-TATp) to form TATp-LNCs and then covered by pH-sensitive graft copolymers of long PEG chains (PGA-g-PEG(2k)). The DSF-S-LNCs had sizes in the range of 60-90 nm and were stable in the presence of 50% plasma. DSF-S-LNCs exhibited higher intracellular uptake and antitumor activity at pH 6.5 than at pH 7.4. The preincubation of Cu showed that the DSF cytotoxicity was based on the accumulation of Cu in Hep G2 cells. Pharmacokinetic studies showed the markedly improved pharmacokinetic profiles of DSF-S-LNCs (AUC= 3921.391 μg/L·h, t(1/2z) = 1.294 h) compared with free DSF (AUC = 907.724 μg/L·h, t(1/2z) = 0.252 h). The in vivo distribution of S-LNCs was investigated using Cy5.5 as a fluorescent probe. In tumor-bearing mice, the delivery efficiency of S-LNCs was found to be 496.5% higher than that of free Cy5.5 and 74.5% higher than that of LNCs in tumors. In conclusion, DSF-S-LNCs increased both the stability and tumor internalization and further increased the cytotoxicity because of the higher copper content.

  11. Salacia oblonga root improves cardiac lipid metabolism in Zucker diabetic fatty rats: Modulation of cardiac PPAR-{alpha}-mediated transcription of fatty acid metabolic genes

    SciTech Connect

    Huang, Tom H.-W.; Yang Qinglin; Harada, Masaki; Uberai, Jasna; Radford, Jane; Li, George Q.; Yamahara, Johji; Roufogalis, Basil D.; Li Yuhao . E-mail: yuhao@pharm.usyd.edu.au

    2006-01-15

    Excess cardiac triglyceride accumulation in diabetes and obesity induces lipotoxicity, which predisposes the myocytes to death. On the other hand, increased cardiac fatty acid (FA) oxidation plays a role in the development of myocardial dysfunction in diabetes. PPAR-{alpha} plays an important role in maintaining homeostasis of lipid metabolism. We have previously demonstrated that the extract from Salacia oblonga root (SOE), an Ayurvedic anti-diabetic and anti-obesity medicine, improves hyperlipidemia in Zucker diabetic fatty (ZDF) rats (a genetic model of type 2 diabetes and obesity) and possesses PPAR-{alpha} activating properties. Here we demonstrate that chronic oral administration of SOE reduces cardiac triglyceride and FA contents and decreases the Oil red O-stained area in the myocardium of ZDF rats, which parallels the effects on plasma triglyceride and FA levels. Furthermore, the treatment suppressed cardiac overexpression of both FA transporter protein-1 mRNA and protein in ZDF rats, suggesting inhibition of increased cardiac FA uptake as the basis for decreased cardiac FA levels. Additionally, the treatment also inhibited overexpression in ZDF rat heart of PPAR-{alpha} mRNA and protein and carnitine palmitoyltransferase-1, acyl-CoA oxidase and 5'-AMP-activated protein kinase mRNAs and restored the downregulated acetyl-CoA carboxylase mRNA. These results suggest that SOE inhibits cardiac FA oxidation in ZDF rats. Thus, our findings suggest that improvement by SOE of excess cardiac lipid accumulation and increased cardiac FA oxidation in diabetes and obesity occurs by reduction of cardiac FA uptake, thereby modulating cardiac PPAR-{alpha}-mediated FA metabolic gene transcription.

  12. Possible involvement of membrane lipids peroxidation and oxidation of catalytically essential thiols of the cerebral transmembrane sodium pump as component mechanisms of iron-mediated oxidative stress-linked dysfunction of the pump's activity.

    PubMed

    Omotayo, T I; Akinyemi, G S; Omololu, P A; Ajayi, B O; Akindahunsi, A A; Rocha, J B T; Kade, I J

    2015-01-01

    The precise molecular events defining the complex role of oxidative stress in the inactivation of the cerebral sodium pump in radical-induced neurodegenerative diseases is yet to be fully clarified and thus still open. Herein we investigated the modulation of the activity of the cerebral transmembrane electrogenic enzyme in Fe(2+)-mediated in vitro oxidative stress model. The results show that Fe(2+) inhibited the transmembrane enzyme in a concentration dependent manner and this effect was accompanied by a biphasic generation of aldehydic product of lipid peroxidation. While dithiothreitol prevented both Fe(2+) inhibitory effect on the pump and lipid peroxidation, vitamin E prevented only lipid peroxidation but not inhibition of the pump. Besides, malondialdehyde (MDA) inhibited the pump by a mechanism not related to oxidation of its critical thiols. Apparently, the low activity of the pump in degenerative diseases mediated by Fe(2+) may involve complex multi-component mechanisms which may partly involve an initial oxidation of the critical thiols of the enzyme directly mediated by Fe(2+) and during severe progression of such diseases; aldehydic products of lipid peroxidation such as MDA may further exacerbate this inhibitory effect by a mechanism that is likely not related to the oxidation of the catalytically essential thiols of the ouabain-sensitive cerebral electrogenic pump.

  13. CD44 interaction with ankyrin and IP3 receptor in lipid rafts promotes hyaluronan-mediated Ca2+ signaling leading to nitric oxide production and endothelial cell adhesion and proliferation.

    PubMed

    Singleton, Patrick A; Bourguignon, Lilly Y W

    2004-04-15

    In this study, we have showed that aortic endothelial cells (GM7372A cell line) express CD44v10 [a hyaluronan (HA) receptor], which is significantly enriched in cholesterol-containing lipid rafts (characterized as caveolin-rich plasma membrane microdomains). HA binding to CD44v10 promotes recruitment of the cytoskeletal protein, ankyrin and inositol 1,4,5-triphosphate (IP3) receptor into cholesterol-containing lipid rafts. The ankyrin repeat domain (ARD) of ankyrin is responsible for binding IP3 receptor to CD44v10 at lipid rafts and subsequently triggering HA/CD44v10-mediated intracellular calcium (Ca2+) mobilization leading to a variety of endothelial cell functions such as nitric oxide (NO) production, cell adhesion and proliferation. Further analyses indicate (i) disruption of lipid rafts by depleting cholesterol from the membranes of GM7372A cells (using methyl-beta-cyclodextrin treatment) or (ii) interference of endogenous ankyrin binding to CD44 and IP3 receptor using overexpression of ARD fragments (by transfecting cells with ARDcDNA) not only abolishes ankyrin/IP3 receptor accumulation into CD44v10/cholesterol-containing lipid rafts, but also blocks HA-mediated Ca2+ signaling and endothelial cell functions. Taken together, our findings suggest that CD44v10 interaction with ankyrin and IP3 receptor in cholesterol-containing lipid rafts plays an important role in regulating HA-mediated Ca2+ signaling and endothelial cell functions such as NO production, cell adhesion and proliferation.

  14. A Lipid Mediator Hepoxilin A3 Is a Natural Inducer of Neutrophil Extracellular Traps in Human Neutrophils

    PubMed Central

    Douda, David N.; Grasemann, Hartmut; Pace-Asciak, Cecil

    2015-01-01

    Pulmonary exacerbations in cystic fibrosis airways are accompanied by inflammation, neutrophilia, and mucous thickening. Cystic fibrosis sputum contains a large amount of uncleared DNA contributed by neutrophil extracellular trap (NET) formation from neutrophils. The exact mechanisms of the induction of NETosis in cystic fibrosis airways remain unclear, especially in uninfected lungs of patients with early cystic fibrosis lung disease. Here we show that Hepoxilin A3, a proinflammatory eicosanoid, and the synthetic analog of Hepoxilin B3, PBT-3, directly induce NETosis in human neutrophils. Furthermore, we show that Hepoxilin A3-mediated NETosis is NADPH-oxidase-dependent at lower doses of Hepoxilin A3, while it is NADPH-oxidase-independent at higher doses. Together, these results demonstrate that Hepoxilin A3 is a previously unrecognized inducer of NETosis in cystic fibrosis lungs and may represent a new therapeutic target for treating cystic fibrosis and other inflammatory lung diseases. PMID:25784781

  15. Biodistribution of Small Interfering RNA at the Organ and Cellular Levels after Lipid Nanoparticle-mediated Delivery

    PubMed Central

    Shi, Bin; Keough, Ed; Matter, Andrea; Leander, Karen; Young, Stephanie; Carlini, Ed; Sachs, Alan B.; Tao, Weikang; Abrams, Marc; Howell, Bonnie; Sepp-Lorenzino, Laura

    2011-01-01

    Chemically stabilized small interfering RNA (siRNA) can be delivered systemically by intravenous injection of lipid nanoparticles (LNPs) in rodents and primates. The biodistribution and kinetics of LNP–siRNA delivery in mice at organ and cellular resolution have been studied using immunofluorescence (IF) staining and quantitative polymerase chain reaction (qPCR). At 0.5 and 2 hr post tail vein injection of Cy5-labeled siRNA encapsulated in LNP, the organ rank-order of siRNA levels is liver > spleen > kidney, with only negligible accumulation in duodenum, lung, heart, and brain. Similar conclusions were drawn by using qPCR to measure tissue siRNA levels as a secondary end point. siRNA levels in these tissues decreased by more than 10-fold after 24 hr. Within the liver, LNPs delivered siRNA to hepatocytes, Kupffer cells, and sinusoids in a time-dependent manner, as revealed by IF staining and signal quantitation methods established using OPERA/Columbus software. siRNA first accumulated in liver sinusoids and trafficked to hepatocytes by 2 hr post dose, corresponding to the onset of target mRNA silencing. Fluorescence in situ hybridization methods were used to detect both strands of siRNA in fixed tissues. Collectively, the authors have implemented a platform to evaluate biodistribution of siRNA across cell types and across tissues in vivo, with the objective of elucidating the pharmacokinetic and pharmacodynamic relationship to guide optimization of delivery vehicles. PMID:21804077

  16. Synthesis of Functionalized Dialkyl Ketones From Carboxylic Acid Derivatives and Alkyl Halides

    PubMed Central

    Wotal, Alexander C.; Weix, Daniel J.

    2012-01-01

    Unsymmetrical dialkyl ketones can be directly prepared by the nickel-catalyzed reductive coupling of carboxylic acid chlorides or (2-pyridyl)thioesters with alkyl iodides or benzylic chlorides. A wide variety of functional groups are tolerated by this process, including common nitrogen protecting groups and C-B bonds. Even hindered ketones flanked by tertiary and secondary centers can be formed. The mechanism is proposed to involve the reaction of a (L)Ni(alkyl)2 intermediate with the carboxylic acid derivative. PMID:22360350

  17. Copper-catalyzed asymmetric conjugate reduction as a route to novel β-azaheterocyclic acid derivatives

    PubMed Central

    Rainka, Matthew P.; Aye, Yimon; Buchwald, Stephen L.

    2004-01-01

    A chiral copper-hydride catalyst for the asymmetric conjugate reduction of α,β-unsaturated carbonyl compounds has been used for the reduction of substrates containing β-nitrogen substituents. A new set of reaction conditions has allowed for a variety of β-azaheterocyclic acid derivatives to be synthesized in excellent yields and with high degrees of enantioselectivity. In addition, the effect that the nature of the nitrogen substituent has on the rate of the conjugate reduction reaction has been explored. PMID:15067136

  18. Bicyclic alpha,omega-dicarboxylic acid derivatives from a colonial tunicate of the family Polyclinidae.

    PubMed

    Bao, Baoquan; Dang, Hung The; Zhang, Ping; Hong, Jongki; Lee, Chong-O; Cho, Hee Young; Jung, Jee H

    2009-11-01

    In the course of our search for bioactive metabolites from a colonial tunicate of the family Polyclinidae, six new (1-6) cyclic fatty acid derivatives were isolated. Their planar structures were established on the basis of NMR and MS spectroscopic analyses. The relative configuration was determined by NOESY experiment. Compounds 1-6 represent a fused bicyclic skeleton possibly derived from alpha,omega-dicarboxylic acids such as eicosanedioic acid or docosanedioic acid via a Diels-Alder type of cyclization. Compounds 1-4 and 6 showed mild cytotoxicity against a panel of five human solid tumor cell lines.

  19. Synthesis and Bioactivity of (R)-Ricinoleic Acid Derivatives: A Review.

    PubMed

    Pabiś, Sylwia; Kula, Józef

    2016-01-01

    (R)-Ricinoleic acid (RA) [(12R,9Z)-hydroxyoctadecenoic acid], the main compound of castor seed oil, because of its unusual structure readily undergoes multi-directional chemical and biochemical transformations to produce derivatives with the retained carbon skeleton or with its degradation. Many of these are of high biological activity, as documented by an in vitro study, and possess therapeutic potential. This review article provides an overview of the recent developments in the area of synthesis of RA based compounds with anticancer and antimicrobial activities. Moreover, the antiinflammatory and analgesic properties of some ricinoleic acid derivatives are also highlighted.

  20. A benzoic acid derivative and flavokawains from Piper species as schistosomiasis vector controls.

    PubMed

    Rapado, Ludmila N; Freitas, Giovana C; Polpo, Adriano; Rojas-Cardozo, Maritza; Rincón, Javier V; Scotti, Marcus T; Kato, Massuo J; Nakano, Eliana; Yamaguchi, Lydia F

    2014-04-23

    The search of alternative compounds to control tropical diseases such as schistosomiasis has pointed to secondary metabolites derived from natural sources. Piper species are candidates in strategies to control the transmission of schistosomiasis due to their production of molluscicidal compounds. A new benzoic acid derivative and three flavokawains from Piper diospyrifolium, P. cumanense and P. gaudichaudianum displayed significant activities against Biomphalaria glabrata snails. Additionally, "in silico" studies were performed using docking assays and Molecular Interaction Fields to evaluate the physical-chemical differences among the compounds in order to characterize the observed activities of the test compounds against Biomphalaria glabrata snails.

  1. Synthesis and biological evaluation of new heteroaryl carboxylic acid derivatives as anti-inflammatory-analgesic agents.

    PubMed

    Abouzid, Khaled Abouzid Mohamed; Khalil, Nadia Abdalla; Ahmed, Eman Mohamed; Zaitone, Sawsan Abo-Bakr

    2013-01-01

    A series of nicotinic acid derivatives structurally related to niflumic acid and certain pyridazine-containing compounds have been synthesized and characterized by analytical and spectral data. All compounds were screened for their potential analgesic and anti-inflammatory activities. The compounds which displayed analgesic and anti-inflammatory activities were tested for ulcerogenicity and screened for in vivo inhibition of certain inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and cyclooxygenase-2 (COX-2). Compounds 1c, 2a, 2b, and 5a have shown potent analgesic and anti-inflammatory activities.

  2. HYPERSENSITIVITY TO PENICILLENIC ACID DERIVATIVES IN HUMAN BEINGS WITH PENICILLIN ALLERGY

    PubMed Central

    Parker, Charles W.; Shapiro, Jack; Kern, Milton; Eisen, Herman N.

    1962-01-01

    Multifunctional derivatives of penicillenic acid are effective elicitors of wheal-and-erythema skin responses in humans allergic to penicillin. Of the effective derivatives, penicilloyl-polylysines are particularly attractive as skin test reagents because they appear to be incapable of inducing antibody formation. The skin responses are specifically inhibitable in most instances by homologous unifunctional haptens. The penicillenic acid derivatives which appear to be determinants of human allergic reactions to penicillin are: penicilloyl, penicillenate, and groups of the penamaldate-penilloaldehyde type. Of these, the most significant appears to be the penicilloyl-lysyl determinant. PMID:14483916

  3. Quantitation of flavanols, proanthocyanidins, isoflavones, flavanones, dihydrochalcones, stilbenes, and benzoic Acid derivatives after identification by LC-MS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A general method was developed for the systematic quantitation of catechins, proanthocyanidins, isoflavones, flavanones, dihydrochalcones, stilbenes, and hydroxybenzoic acid derivatives (mainly hydrolyzable tannins) using the UV relative mole response factors (MRRF) of the reference standard from ea...

  4. iNOS null MRL+/+ mice show attenuation of trichloroethene-mediated autoimmunity: contribution of reactive nitrogen species and lipid-derived reactive aldehydes

    PubMed Central

    Wang, Gangduo; Wakamiya, Maki; Wang, Jianling; Ansari, G.A.S.; Khan, M. Firoze

    2015-01-01

    Earlier studies from our laboratory in MRL+/+ mice suggest that free radicals, especially overproduction of reactive nitrogen species (RNS) and lipid-derived reactive aldehydes (LDRAs), are associated with trichloroethene (TCE)-mediated autoimmune response. The current study was undertaken to further assess the contribution of RNS and LDRAs in TCE-mediated autoimmunity by using iNOS-null MRL+/+ mice. iNOS-null MRL+/+ mice were obtained by backcrossing iNOS-null mice (B6.129P2-Nos2tm1Lau/J) to MRL +/+ mice. Female MRL+/+ and iNOS-null MRL+/+ mice were given TCE (10 mmol/kg, i.p., every 4th day) for 6 weeks; their respective controls received corn oil only. TCE exposure led to significantly increased iNOS mRNA in livers, iNOS protein in livers and sera, increased nitrotyrosine (NT) formation in both livers and sera, induction of MDA-/HNE-protein adducts in livers and their respective antibodies in sera along with significant increases in serum antinuclear antibodies (ANA) and anti-dsDNA in MRL+/+ mice. Even though in iNOS-null MRL+/+ mice, the iNOS and NT levels were negligible in both TCE-treated and untreated groups, TCE treatment still led to significant increases in MDA-/HNE-protein adducts and their respective antibodies along with increases in serum ANA and anti-dsDNA compared to controls. Most remarkably, the increases in serum ANA and anti-dsDNA induced by TCE in the iNOS-null MRL+/+ mice were significantly less pronounced compared to that in MRL+/+ mice. Our results provide further evidence that both RNS and LDRAs contribute to TCE-induced autoimmunity in MRL+/+ mice, and iNOS deficiency attenuates this autoimmune response. PMID:26472195

  5. iNOS null MRL+/+ mice show attenuation of trichloroethene-mediated autoimmunity: contribution of reactive nitrogen species and lipid-derived reactive aldehydes.

    PubMed

    Wang, Gangduo; Wakamiya, Maki; Wang, Jianling; Ansari, G A S; Firoze Khan, M

    2015-12-01

    Earlier studies from our laboratory in MRL+/+ mice suggest that free radicals, especially overproduction of reactive nitrogen species (RNS) and lipid-derived reactive aldehydes (LDRAs), are associated with trichloroethene (TCE)-mediated autoimmune response. The current study was undertaken to further assess the contribution of RNS and LDRAs in TCE-mediated autoimmunity by using iNOS-null MRL+/+ mice. iNOS-null MRL+/+ mice were obtained by backcrossing iNOS-null mice (B6.129P2-Nos2(tm1Lau)/J) to MRL +/+ mice. Female MRL+/+ and iNOS-null MRL+/+ mice were given TCE (10 mmol/kg, i.p., every 4(th) day) for 6 weeks; their respective controls received corn oil only. TCE exposure led to significantly increased iNOS mRNA in livers, iNOS protein in livers and sera, increased nitrotyrosine (NT) formation in both livers and sera, induction of MDA-/HNE-protein adducts in livers and their respective antibodies in sera along with significant increases in serum antinuclear antibodies (ANA) and anti-dsDNA in MRL+/+ mice. Even though in iNOS-null MRL+/+ mice, the iNOS and NT levels were negligible in both TCE-treated and untreated groups, TCE treatment still led to significant increases in MDA-/HNE-protein adducts and their respective antibodies along with increases in serum ANA and anti-dsDNA compared to controls. Most remarkably, the increases in serum ANA and anti-dsDNA induced by TCE in the iNOS-null MRL+/+ mice were significantly less pronounced compared to that in MRL+/+ mice. Our results provide further evidence that both RNS and LDRAs contribute to TCE-induced autoimmunity in MRL+/+ mice, and iNOS deficiency attenuates this autoimmune response.

  6. Maresin-like lipid mediators are produced by leukocytes and platelets and rescue reparative function of diabetes-impaired macrophages.

    PubMed

    Hong, Song; Lu, Yan; Tian, Haibin; Alapure, Bhagwat V; Wang, Quansheng; Bunnell, Bruce A; Laborde, James Monroe

    2014-10-23

    Nonhealing diabetic wounds are associated with impaired macrophage (Mf) function. Leukocytes and platelets (PLT) play crucial roles in wound healing by poorly understood mechanisms. Here we report the identification and characterization of the maresin-like(L) mediators 14,22-dihydroxy-docosa-4Z,7Z,10Z,12E,16Z,19Z-hexaenoic acids, 14S,22-diHDHA (maresin-L1), and 14R,22-diHDHA (maresin-L2) that are produced by leukocytes and PLT and involved in wound healing. We show that 12-lipoxygenase-initiated 14S-hydroxylation or cytochrome P450 catalyzed 14R-hydroxylation and P450-initiated ω(22)-hydroxylation are required for maresin-L biosynthesis. Maresin-L treatment restores reparative functions of diabetic Mfs, suggesting that maresin-Ls act as autocrine/paracrine factors responsible for, at least in part, the reparative functions of leukocytes and PLT in wounds. Additionally, maresin-L ameliorates Mf inflammatory activation and has the potential to suppress the chronic inflammation in diabetic wounds caused by activation of Mfs. These findings provide initial insights into maresin-L biosynthesis and mechanism of action and potentially offer a therapeutic option for better treatment of diabetic wounds.

  7. Combined anticalcification treatment of bovine pericardium with decellularization and hyaluronic acid derivative.

    PubMed

    Zhu, Deyi; Jin, Liqiang; Wang, Xuemei; Xu, Li; Liu, Tianqi

    2014-01-01

    The objective of this work was to evaluate the effect of decellularization and hyaluronic acid derivative on the improvement of anticalcification of glutaraldehyde fixed bovine pericardium (GFBP) using a rat subcutaneous implantation model A cell extraction process was employed to remove the cells and cellular components from bovine pericardium (BP), leaving a framework of largely insoluble collagen. Then acellular BP was cross-linked by glutaraldehyde solution and treated with hyaluronic acid derivative (HA-ADH) which was obtained by coupling adipic dihydrazide (ADH) on-COOH of hyaluronic acid (HA). The results of in vivo calcification tests showed that the calcium content was decreased dramatically by decellularization alone (from 28.07 ± 18.87 to 2.44 ± 0.55 μg Ca/mg dry tissue after 8 weeks' implantation), and even less concentration was shown by the combination of HA derivative treatment and decellularization (GFaBP-HA group) (0.25 ± 0.08 μg Ca/mg dry tissue after 8 weeks' implantation). In addition, GFaBP-HA group not only presented a lower degree of calcification, but also showed lower ratios of Ca/P molar, which corresponded to amorphous calcium phosphates. The obtained results indicated that GFaBP-HA was a potential candidate for the manufacture of anticalcification bioprostheses.

  8. Ursolic acid derivative ameliorates streptozotocin-induced diabestic bone deleterious effects in mice

    PubMed Central

    Yu, Su-Guo; Zhang, Cheng-Jie; Xu, Xiu-E; Sun, Ji-Hua; Zhang, Li; Yu, Peng-Fei

    2015-01-01

    Objective: This study was performed to investigate bone deteriorations of diabetic mice in response to the treatment of ursolic acid derivative (UAD). Methods: The biomarkers in serum and urine were measured, tibias were taken for the measurement on gene and protein expression and histomorphology analysis, and femurs were taken for the measurement on bone Ca and three-dimensional architecture of trabecular bone. Results: UAD showed a greater increase in bone Ca, BMD and significantly increased FGF-23 and OCN, reduced PTH and CTX in diabetic mice. UAD reversed STZ-induced trabecular deleterious effects and stimulated bone remodeling. The treatment of STZ group with UAD significantly elevated the ratio of OPG/RANKL. Moreover, insulin and IGF-1 showed a negative correlation with both FBG and Hb1Ac in STZ group. We attributed down-regulating the level of Hb1Ac in diabetic mice to that ursolic acid derivative could primely control blood sugar levels. After analyzing of two adipocyte markers, PPARγ and aP2, increased expression in the tibias of diabetic mice, and UAD could improve STZ-induced adipocyte dysfunction. Conclusions: These results demonstrated that UAD could ameliorate STZ-induced bone deterioration through improving adipocyte dysfunction and enhancing new bone formation and inhibiting absorptive function of osteoclast in the bone of diabetic mice. PMID:26097549

  9. Poly(L-aspartic acid) derivative soluble in a volatile organic solvent for biomedical application.

    PubMed

    Oh, Nam Muk; Oh, Kyung Taek; Youn, Yu Seok; Lee, Eun Seong

    2012-09-01

    In order to develop a novel functional poly(L-amino acid) that can dissolve in volatile organic solvents, we prepared poly[L-aspartic acid-g-(3-diethylaminopropyl)]-b-poly(ethylene glycol) [poly(L-Asp-g-DEAP)-b-PEG] via the conjugation of 3-diethylaminopropyl (DEAP) to carboxylate groups of poly(L-Asp) (M(n) 4 K)-b-PEG (M(n) 2 K). This poly(L-aspartic acid) derivative evidenced a relatively high solubility in volatile organic solvents such as dichloromethane, chloroform, and acetone. We fabricated a model nanostructure (i.e., polymeric micelle) using poly(L-Asp-g-DEAP)-b-PEG by the film rehydration method, which involves the simple removal of the volatile organic solvent (dichloromethane) used to dissolve polymer, reducing concerns about organic solvents remaining in a nano-sized particle. Interestingly, this micelle showed the pH-stimulated release of encapsulated model drug [i.e., doxorubicin (DOX)] due to the protonation of DEAP according to the pH of the solution. We expect that this poly(L-aspartic acid) derivative promises to provide pharmaceutical potential for constituting a new stimuli-sensitive drug carrier for various drug molecules.

  10. Copper extraction by fatty hydroxamic acids derivatives synthesized based on palm kernel oil.

    PubMed

    Haron, Jelas; Jahangirian, Hossein; Silong, Sidik; Yusof, Nor Azah; Kassim, Anuar; Moghaddam, Roshanak Rafiee; Peyda, Mazyar; Abdollahi, Yadollah; Amin, Jamileh; Gharayebi, Yadollah

    2012-01-01

    Fatty hydroxamic acids derivatives based on palm kernel oil which are phenyl fatty hydroxamic acids (PFHAs), methyl fatty hydroxamic acids (MFHAs), isopropyl fatty hydroxamic acids (IPFHAs) and benzyl fatty hydroxamic acids (BFHAs) were applied as chelating agent for copper liquid-liquid extraction. The extraction of copper from aqueous solution by MFHAs, PFHAs, BFHAs or IPFHAs were carried out in hexane as an organic phase through the formation of copper methyl fatty hydroxamate (Cu-MFHs), copper phenyl fatty hydroxamate (Cu-PFHs), copper benzyl fatty hydroxamate (Cu-BFHs) and copper isopropyl fatty hydroxamate (Cu-IPFHs). The results showed that the fatty hydroxamic acid derivatives could extract copper at pH 6.2 effectively with high percentage of extraction (the percentages of copper extraction by MFHAs, PFHAs, IPFHs and BFHAs were found to be 99.3, 87.5, 82.3 and 90.2%, respectively). The extracted copper could be quantitatively stripped back into sulphuric acid (3M) aqueous solution. The obtained results showed that the copper recovery percentages from Cu-MFHs, Cu-PFHs, Cu-BFHs and Cu-IPFHs are 99.1, 99.4, 99.6 and 99.9 respectively. The copper extraction was not affected by the presence of a large amount of Mg (II), Ni (II), Al (III), Mn (II) and Co (II) ions in the aqueous solution.

  11. Anti-HIV activities of natural antioxidant caffeic acid derivatives: toward an antiviral supplementation diet.

    PubMed

    Bailly, Fabrice; Cotelle, Philippe

    2005-01-01

    Since 1996, highly active antiretroviral therapy (HAART) was designed to rapidly control HIV replication. It has had a significant impact on patient health and progression of AIDS in developed countries, but its success has not been complete. HAART strategy still suffers from issues of patient compliance, cost, deleterious side effects and emerging drug resistance. Therefore, expansion of novel anti-HIV drugs and targets will be critical in the coming years. In this context, discovering anti-HIV agents from natural sources and particularly from plants, may highlight the principle of a nutritional antioxidant antiretroviral diet. In this paper, we review the putative anti-HIV activity of simple caffeic acid derivatives, together with their antioxidant properties. Toxicity, metabolism and bioavailability, when known, will also be detailed. Well-known caffeic acid derivatives, such as chicoric, rosmarinic and lithospermic acids, may be designed as future leads multi-target anti-HIV compounds and the plants and vegetables containing them as potent nutritional therapeutic supplementation source. They are not expected to replace the actual antiretroviral therapy, but more likely, to complete and perhaps lighten it by adapted diet.

  12. Biotechnological production of caffeic acid derivatives from cell and organ cultures of Echinacea species.

    PubMed

    Murthy, Hosakatte Niranjana; Kim, Yun-Soo; Park, So-Young; Paek, Kee-Yoeup

    2014-09-01

    Caffeic acid derivatives (CADs) are a group of bioactive compounds which are produced in Echinacea species especially Echinacea purpurea, Echinacea angustifolia, and Echinacea pallida. Echinacea is a popular herbal medicine used in the treatment of common cold and it is also a prominent dietary supplement used throughout the world. Caffeic acid, chlorogenic acid (5-O-caffeoylquinic acid), caftaric acid (2-O-caffeoyltartaric acid), cichoric acid (2, 3-O-dicaffeoyltartaric acid), cynarin, and echinacoside are some of the important CADs which have varied pharmacological activities. The concentrations of these bioactive compounds are species specific and also they vary considerably with the cultivated Echinacea species due to geographical location, stage of development, time of harvest, and growth conditions. Due to these reasons, plant cell and organ cultures have become attractive alternative for the production of biomass and caffeic acid derivatives. Adventitious and hairy roots have been induced in E. pupurea and E. angustifolia, and suspension cultures have been established from flask to bioreactor scale for the production of biomass and CADs. Tremendous progress has been made in this area; various bioprocess methods and strategies have been developed for constant high-quality productivity of biomass and secondary products. This review is aimed to discuss biotechnological methods and approaches employed for the sustainable production of CADs.

  13. Dissociation of the trimeric gp41 ectodomain at the lipid-water interface suggests an active role in HIV-1 Env-mediated membrane fusion.

    PubMed

    Roche, Julien; Louis, John M; Grishaev, Alexander; Ying, Jinfa; Bax, Adriaan

    2014-03-04

    The envelope glycoprotein gp41 mediates the process of membrane fusion that enables entry of the HIV-1 virus into the host cell. The actual fusion process involves a switch from a homotrimeric prehairpin intermediate conformation, consisting of parallel coiled-coil helices, to a postfusion state where the ectodomains are arranged as a trimer of helical hairpins, adopting a six-helix bundle (6HB) state. Here, we show by solution NMR spectroscopy that a water-soluble 6HB gp41 ectodomain binds to zwitterionic detergents that contain phosphocholine or phosphatidylcholine head groups and phospholipid vesicles that mimic T-cell membrane composition. Binding results in the dissociation of the 6HB and the formation of a monomeric state, where its two α-helices, N-terminal heptad repeat (NHR) and C-terminal heptad repeat (CHR), become embedded in the lipid-water interface of the virus and host cell. The atomic structure of the gp41 ectodomain monomer, based on NOE distance restraints and residual dipolar couplings, shows that the NHR and CHR helices remain mostly intact, but they completely lose interhelical contacts. The high affinity of the ectodomain helices for phospholipid surfaces suggests that unzippering of the prehairpin intermediate leads to a state where the NHR and CHR helices become embedded in the host cell and viral membranes, respectively, thereby providing a physical force for bringing these membranes into close juxtaposition before actual fusion.

  14. In silico modelling of prostacyclin and other lipid mediators to nuclear receptors reveal novel thyroid hormone receptor antagonist properties.

    PubMed

    Perez Diaz, Noelia; Zloh, Mire; Patel, Pryank; Mackenzie, Louise S

    2016-01-01

    Prostacyclin (PGI2) is a key mediator involved in cardiovascular homeostasis, acting predominantly on two receptor types; cell surface IP receptor and cytosolic peroxisome proliferator activated receptor (PPAR) β/δ. Having a very short half-life, direct methods to determine its long term effects on cells is difficult, and little is known of its interactions with nuclear receptors. Here we used computational chemistry methods to investigate the potential for PGI2, beraprost (IP receptor agonist), and GW0742 (PPARβ/δ agonist), to bind to nuclear receptors, confirmed with pharmacological methods. In silico screening predicted that PGI2, beraprost, and GW0742 have the potential to bind to different nuclear receptors, in particular thyroid hormone β receptor (TRβ) and thyroid hormone α receptor (TRα). Docking analysis predicts a binding profile to residues thought to have allosteric control on the TR ligand binding site. Luciferase reporter assays confirmed that beraprost and GW0742 display TRβ and TRα antagonistic properties; beraprost IC50 6.3 × 10(-5)mol/L and GW0742 IC50 4.9 × 10(-6) mol/L. Changes to triiodothyronine (T3) induced vasodilation of rat mesenteric arteries measured on the wire myograph were measured in the presence of the TR antagonist MLS000389544 (10(-5) mol/L), beraprost (10(-5) mol/L) and GW0742 (10(-5) mol/L); all significantly inhibited T3 induced vasodilation compared to controls. We have shown that both beraprost and GW0742 exhibit TRβ and TRα antagonist behaviour, and suggests that PGI2 has the ability to affect the long term function of cells through binding to and inactivating thyroid hormone receptors.

  15. The effects of derivatives of the nitroxide tempol on UVA-mediated in vitro lipid and protein oxidation.

    PubMed

    Damiani, Elisabetta; Castagna, Riccardo; Greci, Lucedio

    2002-07-01

    Derivatives of tetramethylpiperidines are extensively employed in polymers to prevent photooxidation, and their stabilizing effect is attributed to the activity of the nitroxide radical derived from the parent amine. In this study, we examined the photoprotective effect of a commercial polymer photostabilizer, HALS-1, its corresponding nitroxide, bis(2,2,6,6-tetramethyl-piperidine-1-oxyl-4-yl)sebacate (TINO), and two derivatives of the piperidine nitroxide TEMPOL, 2,2,6,6-tetramethyl-piperidin-4-acetyloxy-1-oxyl (TEMP2) and 2,2,6,6-tetramethyl-piperidin-4-octanoyloxy-1-oxyl (TEMP8) synthesized by us, in liposomes exposed to ultraviolet A (UVA) radiation. For comparison, the UVA-absorber, 4-tert-butyl-4'-methoxydibenzoylmethane (Parsol 1789) used in many suncream formulations, was also included. The nitroxide TINO resulted extremely efficient at inhibiting aldehydic breakdown products deriving from 30 min exposure of liposomes to UVA and the protection was dose-dependent (10-100 microM). The corresponding amine HALS-1 was the least efficient while protection increased in the order: TEMP2 < Parsol 1789 < TEMP 8. HALS-1, TINO, and the two TEMPOL derivatives were also tested in a simple protein system consisting of bovine serum albumin (BSA) exposed to UVA. In this case, these compounds did not inhibit nor enhance UVA-mediated protein carbonyl formation in BSA. The differences in protection between the compounds are discussed in relation to their chemical reactivity, UVA-absorbing capacities, and their molecular structure. Overall, the results obtained envisage the potential use of nitroxide compounds as topical antioxidants.

  16. Stimulation of Microbially Mediated Arsenic Release in Bangladesh Aquifers by Young Carbon Indicated by Radiocarbon Analysis of Sedimentary Bacterial Lipids.

    PubMed

    Whaley-Martin, K J; Mailloux, B J; van Geen, A; Bostick, B C; Silvern, R F; Kim, C; Ahmed, K M; Choudhury, I; Slater, G F

    2016-07-19

    The sources of reduced carbon driving the microbially mediated release of arsenic to shallow groundwater in Bangladesh remain poorly understood. Using radiocarbon analysis of phospholipid fatty acids (PLFAs) and potential carbon pools, the abundance and carbon sources of the active, sediment-associated, in situ bacterial communities inhabiting shallow aquifers (<30 m) at two sites in Araihazar, Bangladesh, were investigated. At both sites, sedimentary organic carbon (SOC) Δ(14)C signatures of -631 ± 54‰ (n = 12) were significantly depleted relative to dissolved inorganic carbon (DIC) of +24 ± 30‰ and dissolved organic carbon (DOC) of -230 ± 100‰. Sediment-associated PLFA Δ(14)C signatures (n = 10) at Site F (-167‰ to +20‰) and Site B (-163‰ to +21‰) were highly consistent and indicated utilization of carbon sources younger than the SOC, likely from the DOC pool. Sediment-associated PLFA Δ(14)C signatures were consistent with previously determined Δ(14)C signatures of microbial DNA sampled from groundwater at Site F indicating that the carbon source for these two components of the subsurface microbial community is consistent and is temporally stable over the two years between studies. These results demonstrate that the utilization of relatively young carbon sources by the subsurface microbial community occurs at sites with varying hydrology. Further they indicate that these young carbon sources drive the metabolism of the more abundant sediment-associated microbial communities that are presumably more capable of Fe reduction and associated release of As. This implies that an introduction of younger carbon to as of yet unaffected sediments (such as those comprising the deeper Pleistocene aquifer) could stimulate microbial communities and result in arsenic release.

  17. Effects of parenteral infusion with fish-oil or safflower-oil emulsion on hepatic lipids, plasma amino acids, and inflammatory mediators in septic rats.

    PubMed

    Chao, C Y; Yeh, S L; Lin, M T; Chen, W J

    2000-04-01

    This study was designed to investigate the effects of preinfusion with total parenteral nutrition (TPN) using fish-oil (FO) versus safflower-oil (SO) emulsion as fat sources on hepatic lipids, plasma amino-acid profiles, and inflammatory-related mediators in septic rats. Normal rats, with internal jugular catheters, were assigned to two different groups and received TPN. TPN provided 300 kcal. kg(-1). d(-1), with 40% of the non-protein energy as fat. All TPN solutions were isonitrogenous and identical in nutrient composition except for the fat emulsion, which was made of SO or FO. After receiving TPN for 6 d, each group of rats was further divided into control and sepsis subgroups. Sepsis was induced by cecal ligation and puncture; control rats received sham operation. All rats were classified into four groups as follows: FO control group (FOC; n = 7), FO sepsis group (FOS; n = 8), SO control group (SOC; n = 8), and SO sepsis group (SOS; n = 9). The results of the study demonstrated that plasma concentrations of triacylglycerol and non-esterified fatty acids did not differ between the FO and SO groups, regardless of whether the animals were septic. SOS had significantly higher total lipids and cholesterol content in the liver than did the SOC group. The FOS group, however, showed no difference from the FOC group. Plasma leucine and isoleucine levels were significantly lower in the SOS group than in the SOC group, whereas no difference in these two amino acids was observed between the FOC and FOS groups. Plasma arginine levels were significantly lower in both septic groups than in the groups without sepsis when either FO or SO was infused. Plasma glutamine levels, however, did not differ across groups. No differences in interleukin-1beta, interleukin-6, tumor necrosis factor-alpha, or leukotriene B(4) concentrations in peritoneal lavage fluid were observed between the two septic groups. These results suggest that catabolic reaction in septic rats preinfused with FO

  18. Effects of parenteral infusion with medium-chain triglycerides and safflower oil emulsions on hepatic lipids, plasma amino acids and inflammatory mediators in septic rats.

    PubMed

    Yeh, S; Chao, C; Lin, M; Chen, W

    2000-04-01

    This study was designed to investigate the effects of preinfusion with total parenteral nutrition (TPN) using medium-chain triglycerides (MCT) versus safflower oil (SO) emulsion as fat sources on hepatic lipids, plasma amino acid profiles, and inflammatory-related mediators in septic rats. Normal rats, with internal jugular catheters, were divided into two groups and received TPN. TPN provided 300kcal/kg/day with 40% of the non-protein energy provided as fat. All TPN solutions were isonitrogenous and identical in nutrient composition except for the fat emulsion, which was made of SO or a mixture of MCT and soybean oil (9:1) (MO). After receiving TPN for 6 days, each group of rats was further divided into control and sepsis subgroups. Sepsis was induced by cecal ligation and puncture, whereas control rats received sham operation. All rats were classified into four groups as follows: MCT control group (MOC, n= 8), MCT sepsis group (MOS, n= 8), safflower oil control group (SOC, n= 8), and safflower oil sepsis group (SOS, n= 11). The results of the study demonstrated that the MOS group had lower hepatic lipids than did the SOS group. Plasma leucine and isoleucine levels were significantly lower in the SOS than in the SOC group, but no differences in these two amino acids were observed between the MOC and MOS groups. Plasma arginine levels were significantly lower in septic groups than in those without sepsis despite whether MCT or safflower oil was infused. Plasma glutamine and alanine levels, however, did not differ between septic and non-septic groups either in the SO or MO groups. No differences in interleukin-1b, interleukin-6, tumor necrosis factor-alpha, and leukotriene B(4)concentrations in peritoneal lavage fluid were observed between the two septic groups. These results suggest that catabolic reaction is septic rats preinfused MCT is not as obvious as those preinfused safflower oil. Compared with safflower oil, TPN with MCT administration has better effects on

  19. Insights into diastereoisomeric characterization of tetrahydropyridazine amino acid derivatives: crystal structures and gas phase ion chemistry.

    PubMed

    Giorgi, Gianluca; Favi, Gianfranco; Attanasi, Orazio A

    2013-08-14

    Structural, conformational properties, and gas phase reactivity of two representative diastereoisomeric members of a series of α,α-tetrahydropyridazine amino acid derivatives have been investigated by using X-ray crystallography, tandem mass spectrometry and theoretical calculations. Both diastereoisomers show an unusual screw-boat conformation of the tetrahydropyridazine ring. While protonated molecules mainly decompose in the gas phase by loss of acetamide, the main reactivity of the [M + Na](+) species consists of loss of PhNCO followed by acetamide and it is strictly dependent upon the stereochemistry of the parent compound. The most stable energy minimized structures obtained by theoretical calculations are in full agreement with the experimental data and allowed us to rationalize the gas phase reaction pathways.

  20. Antioxidative properties of hydroxycinnamic acid derivatives and a phenylpropanoid glycoside. A pulse radiolysis study

    NASA Astrophysics Data System (ADS)

    Lin, Weizhen; Navaratnam, Suppiah; Yao, Side; Lin, Nianyun

    1998-10-01

    Spectral and redox properties of the phenoxyl radicals from hydroxycinnamic acid derivatives and one selected component of phenylpropanoid glycosides, verbascoside, were studied using pulse radiolysis techniques. On the basis of the pH dependence of phenoxyl radical absorptions, the p Ka values for deprotonation of sinapic acid radical and ferulic acid radical are 4.9 and 5.2. The rate constants of one electron oxidation of those antioxidants by azide radical and bromide radical ion were determined at pH 7. The redox potentials of those antioxidants were determined as 0.59-0.71 V vs NHE at pH 7 with reference standard 4-methoxyphenol and resorcinol.

  1. Hydroxamic acid derivatives: a promising scaffold for rational compound optimization in Chagas disease.

    PubMed

    de Menezes, Dayanne da Rocha; Calvet, Claudia Magalhães; Rodrigues, Giseli Capaci; de Souza Pereira, Mirian Claudia; Almeida, Igor Rodrigues; de Aguiar, Alcino Palermo; Supuran, Claudiu T; Vermelho, Alane Beatriz

    2016-12-01

    This work describes the antitrypanocidal activity of two hydroxamic acid derivatives containing o-ethoxy (HAD1) and p-ethoxy (HAD2) as substituent in the aromatic ring linked to the isoxazoline ring. HAD1 and HAD2 induced a significant reduction in the number of intracellular parasites and consequently showed activity on the multiplication of the parasite. Treatment of cardiomyocytes and macrophages with the compounds revealed no significant loss in cell viability. Ultrastructural alterations after treatment of cardiomyocytes or macrophages infected by Trypanosoma cruzi with the IC50 value of HAD1 revealed alterations to amastigotes, showing initial damage seen as swelling of the kinetoplast. This gave a good indication of the ability of the drug to permeate through the host cell membrane as well as its selectivity to the parasite target. Both compounds HAD1 and 2 were able to reduce the cysteine peptidases and decrease the activity of metallopeptidases.

  2. Design and synthesis of N-benzoyl amino acid derivatives as DNA methylation inhibitors.

    PubMed

    Garella, Davide; Atlante, Sandra; Borretto, Emily; Cocco, Mattia; Giorgis, Marta; Costale, Annalisa; Stevanato, Livio; Miglio, Gianluca; Cencioni, Chiara; Fernández-de Gortari, Eli; Medina-Franco, José L; Spallotta, Francesco; Gaetano, Carlo; Bertinaria, Massimo

    2016-11-01

    The inhibition of human DNA Methyl Transferases (DNMT) is a novel promising approach to address the epigenetic dysregulation of gene expression in different diseases. Inspired by the validated virtual screening hit NSC137546, a series of N-benzoyl amino acid analogues was synthesized and obtained compounds were assessed for their ability to inhibit DNMT-dependent DNA methylation in vitro. The biological screening allowed the definition of a set of preliminary structure-activity relationships and the identification of compounds promising for further development. Among the synthesized compounds, L-glutamic acid derivatives 22, 23, and 24 showed the highest ability to prevent DNA methylation in a total cell lysate. Compound 22 inhibited DNMT1 and DNMT3A activity in a concentration-dependent manner in the micromolar range. In addition, compound 22 proved to be stable in human serum and it was thus selected as a starting point for further biological studies.

  3. In vitro trypanocidal activity of dibutyltin dichloride and its fatty acid derivatives.

    PubMed

    Shuaibu, M N; Kanbara, H; Yanagi, T; Ichinose, A; Ameh, D A; Bonire, J J; Nok, A J

    2003-09-01

    Searching for new compounds against pathogenic trypanosomes has been substantially accelerated by the development of in vitro screening assays. In an attempt to explore the chemotherapeutic potential of organotin compounds and to broaden the search for newer trypanocides, fatty acid derivatives of dibutyltin dichloride were synthesized and their in vitro trypanocidal profiles studied on Trypanosoma brucei brucei, Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense. A 24-h time course experiment was conducted with various concentrations of the compounds using a 24-well microtiter plate technique. The compounds tested were trypanocidal in a dose-dependent fashion: inhibiting survival and growth, resulting in irreversible morphological deformation and the eventual death of the parasites. The minimum inhibitory concentrations of the tested diorganotins are at low micromolar ranges: from 0.15-0.75 microM for T. b. brucei, T. b. gambiense and T. b. rhodesiense. These observations suggest that organotin has chemotherapeutic potential.

  4. New neolignan glycoside and an unusual benzoyl malic acid derivative from Maytenus senegalensis leaves.

    PubMed

    Okoye, Festus Basden Chiedu; Agbo, Matthias Onyebuchi; Nworu, Chukwuemeka Sylvester; Nwodo, Ngozi Justina; Esimone, Charles Okechukwu; Osadebe, Patience Ogoamaka; Proksch, Peter

    2015-01-01

    Further investigation of the methanol leaf extract of Maytenus senegalensis led to the isolation of six compounds, including mayselignoside (1) and an unusual benzoyl malic acid derivative, benzoyl R-(+)-malic acid (2). Two known lignan derivatives (+)-lyoniresinol (3) and (-)-isolariciresinol (4), a known neolignan derivative dihydrodehydrodiconiferyl alcohol (5) and the triterpenoid, β-amyrin (6) were also isolated. The structures of these compounds were elucidated by a combination of 1D and 2D NMR and mass spectroscopy. All compounds were tested for cytotoxicity against mouse lymphoma cell line (L5178Y) and for antimicrobial activity against strains of bacteria and fungi. None of the compounds showed promising cytotoxic and/or antimicrobial activities.

  5. Endiandric Acid Derivatives and Other Constituents of Plants from the Genera Beilschmiedia and Endiandra (Lauraceae)

    PubMed Central

    Ndjakou Lenta, Bruno; Chouna, Jean Rodolphe; Nkeng-Efouet, Pepin Alango; Sewald, Norbert

    2015-01-01

    Plants of the Lauraceae family are widely used in traditional medicine and are sources of various classes of secondary metabolites. Two genera of this family, Beilschmiedia and Endiandra, have been the subject of numerous investigations over the past decades because of their application in traditional medicine. They are the only source of bioactive endiandric acid derivatives. Noteworthy is that their biosynthesis contains two consecutive non-enzymatic electrocyclic reactions. Several interesting biological activities for this specific class of secondary metabolites and other constituents of the two genera have been reported, including antimicrobial, enzymes inhibitory and cytotoxic properties. This review compiles information on the structures of the compounds described between January 1960 and March 2015, their biological activities and information on endiandric acid biosynthesis, with 104 references being cited. PMID:26117852

  6. Two glucosylated abscisic acid derivates from avocado seeds (Persea americana Mill. Lauraceae cv. Hass).

    PubMed

    del Refugio Ramos, María; Jerz, Gerold; Villanueva, Socorro; López-Dellamary, Fernando; Waibel, Reiner; Winterhalter, Peter

    2004-04-01

    Phytochemical investigation of avocado seed material (Persea americana Mill., Lauraceae) resulted in the isolation of two glucosylated abscisic acid derivates. One of these was not known as a natural product and can be regarded as a potential 'missing link' in abscisic acid metabolism in plants. After fractionation by high-speed countercurrent chromatography, and multiple steps of column chromatography, structures were elucidated by 1D-, 2D-NMR, electrospray-MS to be the novel beta-d-glucoside of (1'S,6'R)-8'-hydroxyabscisic acid, and (1'R,3'R,5'R,8'S)-epi-dihydrophaseic acid beta-d-glucoside. Absolute configuration was determined by circulardichroism, optical rotation, and by NOE experiments.

  7. Synthesis, evaluation and molecular docking studies of amino acid derived N-glycoconjugates as antibacterial agents.

    PubMed

    Baig, Noorullah; Singh, Rajnish Prakash; Chander, Subhash; Jha, Prabhat Nath; Murugesan, Sankaranarayanan; Sah, Ajay K

    2015-12-01

    Six amino acid derived N-glycoconjugates of d-glucose were synthesized, characterized and tested for antibacterial activity against G(+)ve (Bacillus cereus) as well as G(-)ve (Escherichia coli and Klebsiella pneumoniae) bacterial strains. All the tested compounds exhibited moderate to good antibacterial activity against these bacterial strains. The results were compared with the antibacterial activity of standard drug Chloramphenicol, where results of A5 (Tryptophan derived glycoconjugates) against E. coli and A4 (Isoleucine derived glycoconjugates) against K. pneumoniae bacterial strains are comparable with the standard drug molecule. In silico docking studies were also performed in order to understand the mode of action and binding interactions of these molecules. The docking studies revealed that, occupation of compound A5 at the ATP binding site of subunit GyrB (DNA gyrase, PDB ID: 3TTZ) via hydrophobic and hydrogen bonding interactions may be the reason for its significant in vitro antibacterial activity.

  8. Hydroxycinnamic acid-derived polymers constitute the polyaromatic domain of suberin

    NASA Technical Reports Server (NTRS)

    Bernards, M. A.; Lopez, M. L.; Zajicek, J.; Lewis, N. G.

    1995-01-01

    Suberin is an abundant, complex, intractable, plant cell wall polymeric network that forms both protective and wound-healing layers. Its function is, therefore, critical to the survival of all vascular plants. Its chemical structure and biosynthesis are poorly defined, although it is known to consist of both aromatic and aliphatic domains. While the composition of the aliphatic component has been fairly well characterized, that of the phenolic component has not. Using a combination of specific carbon-13 labeling techniques, and in situ solid state 13C NMR spectroscopic analysis, we now provide the first direct evidence for the nature of the phenolic domain of suberin and report here that it is almost exclusively comprised of a covalently linked, hydroxycinnamic acid-derived polymeric matrix.

  9. Brevianamides and Mycophenolic Acid Derivatives from the Deep-Sea-Derived Fungus Penicillium brevicompactum DFFSCS025

    PubMed Central

    Xu, Xinya; Zhang, Xiaoyong; Nong, Xuhua; Wang, Jie; Qi, Shuhua

    2017-01-01

    Four new compounds (1–4), including two brevianamides and two mycochromenic acid derivatives along with six known compounds were isolated from the deep-sea-derived fungus Penicillium brevicompactum DFFSCS025. Their structures were elucidated by spectroscopic analysis. Moreover, the absolute configurations of 1 and 2 were determined by quantum chemical calculations of the electronic circular dichroism (ECD) spectra. Compound 9 showed moderate cytotoxicity against human colon cancer HCT116 cell line with IC50 value of 15.6 μM. In addition, 3 and 5 had significant antifouling activity against Bugula neritina larval settlement with EC50 values of 13.7 and 22.6 μM, respectively. The NMR data of 6, 8, and 9 were assigned for the first time. PMID:28218640

  10. New hydroxamic acid derivatives of fluoroquinolones: synthesis and evaluation of antibacterial and anticancer properties.

    PubMed

    Rajulu, Gavara Govinda; Bhojya Naik, Halehatty Seephya; Viswanadhan, Abhilash; Thiruvengadam, Jayaraman; Rajesh, Kondodiyil; Ganesh, Sambasivam; Jagadheshan, Hiriyan; Kesavan, Poonimangadu Koppolu

    2014-01-01

    A series of new hydroxamic acid derivatives (6a-f) at C-3 position of fluoroquinolones were designed and synthesized through multistep synthesis. The design concept involved replacement of the 3-carboxylic acid in fluoquinolones with hydroxamic acid as an acid mimicking group. The synthetic work employed in this work provides a good example for the synthesis of pure hydroxamic acid based fluoroquinolones. The synthesized compounds were characterized by (1)H-NMR, electrospray ionization (ESI)-MS and IR. The new compounds were tested for their in vitro antimicrobial and anti-proliferative activity. Out of the six derivatives, compound 6e exhibited moderate antibacterial activity by inhibiting the growth of Escherichia coli and Klebsiella pneumoniae (MIC: 4.00-8.00 µg/mL). Compounds 6b and 6f displayed good growth inhibition against A549 Lung adenocarcinoma and HCT-116 Colon carcinoma cell lines.

  11. Synthesis, spectroscopic and conformational analysis of 1,4-dihydroisonicotinic acid derivatives

    NASA Astrophysics Data System (ADS)

    Goba, Inguna; Turovska, Baiba; Belyakov, Sergey; Liepinsh, Edvards

    2014-09-01

    Structural and conformational properties of 1,4-dihydroisonicotinic acid derivatives, characterized by ester, ketone or cyano functions at positions 3 and 5 in solid and liquid states have been investigated by X-ray analysis and nuclear magnetic resonance and supported by quantum chemical calculations. The dihydropyridine ring in each of the compounds exists in flattened boat-type conformation. The observed ring distortions around the C(4) and N(1) atoms are interrelated. The substituent at N(1) has great influence on nitrogen atom pyramidality. The 1H, 13C and 15N NMR chemical shifts and coupling constants are discussed in terms of their relationship to structural features such as character and position of the substituent in heterocycle, N-alkyl substitution and nitrogen lone pair delocalization within the conjugated system.

  12. Synthesis and film formation of furfuryl- and maleimido carbonic acid derivatives of dextran.

    PubMed

    Elschner, Thomas; Obst, Franziska; Stana-Kleinschek, Karin; Kargl, Rupert; Heinze, Thomas

    2017-04-01

    Carbonic acid derivatives of dextran possessing furfuryl- and maleimido moieties were synthesized and processed into thin films by spin coating. First, products with different degrees of substitution (DS) of up to 3.0 and substitution patterns were obtained and characterized by NMR- and FTIR spectroscopy, as well as elemental analysis. Thin films possessing maleimide groups were obtained by spin coating of maleimido dextran (furan-protected) and dextran furfuryl carbamate that was converted with bismaleimide. The removal of the protecting group (furan) on the thin film was monitored by QCM-D and compared with gravimetric analysis of the bulk material. Film morphology and wettability were determined by means of AFM and contact angle measurements.

  13. New matrix polymers for photo-activated resin composites using di-alpha-fluoroacrylic acid derivatives.

    PubMed

    Kurata, Shigeaki; Yamazaki, Noboru

    2008-07-01

    A novel matrix resin for photo-activated resin composites was developed using alpha-fluoroacrylic acid derivatives. To render resin composites with improved mechanical properties, silica fillers were also used. It was found that the newly developed fluorine-substituted monomer was polymerized quite easily not only by free radical chemical initiators, but also by photoirradiation using free radical photoinitiator system. In particular, the photopolymerization rate of the novel monomer was more than two times faster than that of corresponding methacrylate-based monomer. Composite based on the newly developed matrix resin had higher micro-Vickers hardness and compressive strength values than the methacrylate-based composite, and that it contained only trace residual monomers compared with the methacrylate-based material. The high polymerization conversion of the fluorine-substituted monomer could be attributed to the polar effect or the small steric hindrance of fluorine at the alpha-position.

  14. [Anxiolytic and antidepressant effects of 3-oxypiridine and succinic acid derivatives in alloxan diabetes].

    PubMed

    Volchegorskii, L A; Miroshnichenko, I Yu; Rassokhina, L M; Faizullin, R M; Pryakhina, K E; Kalugina, A V

    2015-03-01

    The effects of 3-oxypyridine and succinic acid derivatives (emoxipine, reamberin and mexidol) on affective disorders in rats with alloxan diabetes were studied. The efficiency of emoxipine, reamberin and mexidol was compared to alpha-lipoic acid, which is considered a "golden standard" in treatment of diabetic neuropathies. Emoxipine, reamberin and mexidol after seven administrations in single doses, that are equivalent to therapeutic range in humans, corrected the anxiety-depressive disorders in rats with alloxan diabetes. Unlike reamberin and alpha-lipoic acid, emoxipine and mexidol corrected the affective status concurrently with the decrease in hyperglycemia. At the same time, emoxipine outperformed mexidol in tranquilizing action (in maximal doses) but yielded mexidol in the antidepressant effect (in minimal doses).

  15. Fatty Acid-Derived Biofuels and Chemicals Production in Saccharomyces cerevisiae.

    PubMed

    Zhou, Yongjin J; Buijs, Nicolaas A; Siewers, Verena; Nielsen, Jens

    2014-01-01

    Volatile energy costs and environmental concerns have spurred interest in the development of alternative, renewable, sustainable, and cost-effective energy resources. Environment-friendly processes involving microbes can be used to synthesize advanced biofuels. These fuels have the potential to replace fossil fuels in supporting high-power demanding machinery such as aircrafts and trucks. From an engineering perspective, the pathway for fatty acid biosynthesis is an attractive route for the production of advanced fuels such as fatty acid ethyl esters, fatty alcohols, and alkanes. The robustness and excellent accessibility to molecular genetics make the yeast Saccharomyces cerevisiae a suitable host for the purpose of bio-manufacturing. Recent advances in metabolic engineering, as well as systems and synthetic biology, have now provided the opportunity to engineer yeast metabolism for the production of fatty acid-derived fuels and chemicals.

  16. Amino Acid Derivatives as New Zinc Binding Groups for the Design of Selective Matrix Metalloproteinase Inhibitors

    PubMed Central

    Giustiniano, Mariateresa; Agamennone, Mariangela; Rossello, Armando; Gomez-Monterrey, Isabel; Novellino, Ettore; Campiglia, Pietro; Vernieri, Ermelinda; Bertamino, Alessia; Carotenuto, Alfonso

    2013-01-01

    A number of matrix metalloproteinases (MMPs) are important medicinal targets for conditions ranging from rheumatoid arthritis to cardiomyopathy, periodontal disease, liver cirrhosis, multiple sclerosis, and cancer invasion and metastasis, where they showed to have a dual role, inhibiting or promoting important processes involved in the pathology. MMPs contain a zinc (II) ion in the protein active site. Small-molecule inhibitors of these metalloproteins are designed to bind directly to the active site metal ions. In an effort to devise new approaches to selective inhibitors, in this paper, we describe the synthesis and preliminary biological evaluation of amino acid derivatives as new zinc binding groups (ZBGs). The incorporation of selected metal-binding functions in more complex biphenyl sulfonamide moieties allowed the identification of one compound able to interact selectively with different MMP enzymatic isoforms. PMID:23555050

  17. Synthesis of anthranilic acid derivatives through iron-catalyzed ortho amination of aromatic carboxamides with N-chloroamines.

    PubMed

    Matsubara, Tatsuaki; Asako, Sobi; Ilies, Laurean; Nakamura, Eiichi

    2014-01-15

    Arenes possessing an 8-quinolinylamide group as a directing group are ortho aminated with N-chloroamines and N-benzoyloxyamines in the presence of an iron/diphosphine catalyst and an organometallic base to produce anthranilic acid derivatives in high yield. The reaction proceeds via iron-catalyzed C-H activation, followed by the reaction of the resulting iron intermediate with N-chloroamine. The choice of the directing group and diphosphine ligand is crucial for obtaining the anthranilic acid derivative with high yield and product selectivity.

  18. Synthesis and characteristics of (Hydrogenated) ferulic acid derivatives as potential antiviral agents with insecticidal activity

    PubMed Central

    2013-01-01

    Background Plant viruses cause many serious plant diseases and are currently suppressed with the simultaneous use of virucides and insecticides. The use of such materials, however, increases the amounts of pollutants in the environment. To reduce environmental contaminants, virucides with insecticidal activity is an attractive option. Results A series of substituted ferulic acid amide derivatives 7 and the corresponding hydrogenated ferulic acid amide derivatives 13 were synthesized and evaluated for their antiviral and insecticidal activities. The majority of the synthesized compounds exhibited good levels of antiviral activity against the tobacco mosaic virus (TMW), with compounds 7a, 7b and 7d in particular providing higher levels of protective and curative activities against TMV at 500 μg/mL than the control compound ribavirin. Furthermore, these compounds displayed good insecticidal activities against insects with piercing-sucking mouthparts, which can spread plant viruses between and within crops. Conclusions Two series of ferulic acid derivatives have been synthesized efficiently. The bioassay showed title compounds not only inhibit the plant viral infection, but also prevented the spread of plant virus by insect vectors. These findings therefore demonstrate that the ferulic acid amides represent a new template for future antiviral studies. PMID:23409923

  19. Identification and quantitation of new glutamic acid derivatives in soy sauce by UPLC/MS/MS.

    PubMed

    Frerot, Eric; Chen, Ting

    2013-10-01

    Glutamic acid is an abundant amino acid that lends a characteristic umami taste to foods. In fermented foods, glutamic acid can be found as a free amino acid formed by proteolysis or as a non-proteolytic derivative formed by microorganisms. The aim of the present study was to identify different structures of glutamic acid derivatives in a typical fermented protein-based food product, soy sauce. An acidic fraction was prepared with anion-exchange solid-phase extraction (SPE) and analyzed by UPLC/MS/MS and UPLC/TOF-MS. α-Glutamyl, γ-glutamyl, and pyroglutamyl dipeptides, as well as lactoyl amino acids, were identified in the acidic fraction of soy sauce. They were chemically synthesized for confirmation of their occurrence and quantified in the selected reaction monitoring (SRM) mode. Pyroglutamyl dipeptides accounted for 770 mg/kg of soy sauce, followed by lactoyl amino acids (135 mg/kg) and γ-glutamyl dipeptides (70 mg/kg). In addition, N-succinoylglutamic acid was identified for the first time in food as a minor compound in soy sauce (5 mg/kg).

  20. Incorporation of salicylic acid derivatives to hydrophilic copolymer systems with biomedical applications.

    PubMed

    Elvira, C; Gallardo, A; Lacroix, N; Schacht, E; San Román, J

    2001-06-01

    Hydrogels based on polymeric derivatives of salicylic acid have been prepared for biomedical applications by free radical copolymerization of 2-hydroxy-4-methacrylamidobenzoic acid, 4HMA, and 2-hydroxy-5-methacrylamidobenzoic acid, 5HMA, with 2- hydroxyethylmethacrylate, HEMA, in a wide range of compositions. The reactivity ratios of 4HMA and 5HMA with HEMA in radical copolymerization processes have been determined from their 1H NMR spectra by applying linearization methods and non-linear least square treatments. Tgs of the corresponding copolymers were analyzed by DSC. The swelling behavior in water of the prepared copolymers was studied in comparison to poly-(HEMA), poly-(4HMA) and poly-(5HMA) hydration degrees, being in all cases superior to 35%. The hydrolytical behavior of the synthesized copolymers was studied at three different pHs (2, 7.4 and 10) determining the release percentage of the salicylic acid derivatives, 4-amino salicylic acid, 4ASA, and 5-amino salicylic acid, 5ASA, analyzed by high performance liquid chromatography (HPLC). The release analysis was followed during 230 days and a pH dependence was observed obtaining the highest release percentages at pH=10, whereas at physiological pH (7.4) the release percentages were in range from 2 to 5% at that time for all copolymer systems. The hydrolytical stability is enough for long-term applications like bone cements, ionomers, etc.

  1. Precision synthesis of bio-based acrylic thermoplastic elastomer by RAFT polymerization of itaconic acid derivatives.

    PubMed

    Satoh, Kotaro; Lee, Dong-Hyung; Nagai, Kanji; Kamigaito, Masami

    2014-01-01

    Bio-based polymer materials from renewable resources have recently become a growing research focus. Herein, a novel thermoplastic elastomer is developed via controlled/living radical polymerization of plant-derived itaconic acid derivatives, which are some of the most abundant renewable acrylic monomers obtained via the fermentation of starch. The reversible addition-fragmentation chain-transfer (RAFT) polymerizations of itaconic acid imides, such as N-phenylitaconimide and N-(p-tolyl)itaconimide, and itaconic acid esters, such as di-n-butyl itaconate and bis(2-ethylhexyl) itaconate, are examined using a series of RAFT agents to afford well-defined polymers. The number-average molecular weights of these polymers increase with the monomer conversion while retaining relatively narrow molecular weight distributions. Based on the successful controlled/living polymerization, sequential block copolymerization is subsequently investigated using mono- and di-functional RAFT agents to produce block copolymers with soft poly(itaconate) and hard poly(itaconimide) segments. The properties of the obtained triblock copolymer are evaluated as bio-based acrylic thermoplastic elastomers.

  2. Synthesis and biological activity of thiazolyl-acetic acid derivatives as possible antimicrobial agents.

    PubMed

    Shirai, Akihiro; Fumoto, Yasuko; Shouno, Tomoaki; Maseda, Hideaki; Omasa, Takeshi

    2013-01-01

    5a-h, a series of (5-substituted-2-methyl-1,3-thiazole-4-yl) acetic acids as heterocyclic acetic acid derivatives, was designed and synthesized from ethyl acetoacetate. The synthesized compounds were screened for their antimicrobial activities against bacterial and fungal strains, and their characteristics were investigated by assays under various temperature and pH conditions. Cytotoxicity was evaluated with the use of sheep erythrocytes and human neonate dermal fibroblasts. Similarly, agents such as lauric acid 6 and parabens 7a-b, which are used as preservative agents for commercial cosmetics and detergents, were assayed for comparison. Although the structure of 5a is simple, comprising a thiazole attached with an octyl group and acetic acid moiety, the compound showed stronger and broader antibacterial and antifungal activities among the 5 series against the tested microbes other than gram-negative bacteria. Interestingly, 5a overcame the weak antifungal activity of parabens 7a-b. Also, the cytotoxicity of 5a was less than that of parabens 7a-b, especially to human dermal fibroblasts. These results suggest that thiazolyl-acetic acid 5a is a potentially effective biocide, and that it could be used as a preservative agent in commercially sold cosmetics and detergents, facilitated by the hydrophilic and charge properties of its carboxylic acid moiety.

  3. De novo biosynthesis of trans-cinnamic acid derivatives in Saccharomyces cerevisiae.

    PubMed

    Gottardi, Manuela; Knudsen, Jan Dines; Prado, Lydie; Oreb, Mislav; Branduardi, Paola; Boles, Eckhard

    2017-03-29

    The production of natural aroma compounds is an expanding field within the branch of white biotechnology. Three aromatic compounds of interest are cinnamaldehyde, the typical cinnamon aroma that has applications in agriculture and medical sciences, as well as cinnamyl alcohol and hydrocinnamyl alcohol, which have applications in the cosmetic industry. Current production methods, which rely on extraction from plant materials or chemical synthesis, are associated with drawbacks regarding scalability, production time, and environmental impact. These considerations make the development of a sustainable microbial-based production highly desirable. Through steps of rational metabolic engineering, we engineered the yeast Saccharomyces cerevisiae as a microbial host to produce trans-cinnamic acid derivatives cinnamaldehyde, cinnamyl alcohol, and hydrocinnamyl alcohol, from externally added trans-cinnamic acid or de novo from glucose as a carbon source. We show that the desired products can be de novo synthesized in S. cerevisiae via the heterologous overexpression of the genes encoding phenylalanine ammonia lyase 2 from Arabidopsis thaliana (AtPAL2), aryl carboxylic acid reductase (acar) from Nocardia sp., and phosphopantetheinyl transferase (entD) from Escherichia coli, together with endogenous alcohol dehydrogenases. This study provides a proof of concept and a strain that can be further optimized for production of high-value aromatic compounds.

  4. Production of fatty acid-derived oleochemicals and biofuels by synthetic yeast cell factories

    PubMed Central

    Zhou, Yongjin J.; Buijs, Nicolaas A.; Zhu, Zhiwei; Qin, Jiufu; Siewers, Verena; Nielsen, Jens

    2016-01-01

    Sustainable production of oleochemicals requires establishment of cell factory platform strains. The yeast Saccharomyces cerevisiae is an attractive cell factory as new strains can be rapidly implemented into existing infrastructures such as bioethanol production plants. Here we show high-level production of free fatty acids (FFAs) in a yeast cell factory, and the production of alkanes and fatty alcohols from its descendants. The engineered strain produces up to 10.4 g l−1 of FFAs, which is the highest reported titre to date. Furthermore, through screening of specific pathway enzymes, endogenous alcohol dehydrogenases and aldehyde reductases, we reconstruct efficient pathways for conversion of fatty acids to alkanes (0.8 mg l−1) and fatty alcohols (1.5 g l−1), to our knowledge the highest titres reported in S. cerevisiae. This should facilitate the construction of yeast cell factories for production of fatty acids derived products and even aldehyde-derived chemicals of high value. PMID:27222209

  5. Modification of the cellulosic component of hemp fibers using sulfonic acid derivatives: Surface and thermal characterization.

    PubMed

    George, Michael; Mussone, Paolo G; Bressler, David C

    2015-12-10

    The aim of this study was to characterize the surface, morphological, and thermal properties of hemp fibers treated with two commercially available, inexpensive, and water soluble sulfonic acid derivatives. Specifically, the cellulosic component of the fibers were targeted, because cellulose is not easily removed during chemical treatment. These acids have the potential to selectively transform the surfaces of natural fibers for composite applications. The proposed method proceeds in the absence of conventional organic solvents and high reaction temperatures. Surface chemical composition and signature were measured using gravimetric analysis, X-ray photoelectron spectroscopy (XPS) and Fourier transform infra-red spectroscopy (FTIR). XPS data from the treated hemp fibers were characterized by measuring the reduction in O/C ratio and an increase in abundance of the C-C-O signature. FTIR confirmed the reaction with the emergence of peaks characteristic of disubstituted benzene and amino groups. Grafting of the sulfonic derivatives resulted in lower surface polarity. Thermogravimetric analysis revealed that treated fibers were characterized by lower percent degradation between 200 and 300 °C, and a higher initial degradation temperature.

  6. Discovery of a novel activator of 5-lipoxygenase from an anacardic acid derived compound collection

    PubMed Central

    Wisastra, Rosalina; Kok, Petra A.M; Eleftheriadis, Nikolaos; Baumgartner, Matthew P.; Camacho, Carlos J.; Haisma, Hidde J.; Dekker, Frank J.

    2013-01-01

    Lipoxygenases (LOXs) and cyclooxygenases (COXs) metabolize poly-unsaturated fatty acids into inflammatory signaling molecules. Modulation of the activity of these enzymes may provide new approaches for therapy of inflammatory diseases. In this study, we screened novel anacardic acid derivatives as modulators of human 5-LOX and COX-2 activity. Interestingly, a novel salicylate derivative 23a was identified as a surprisingly potent activator of human 5-LOX. This compound showed both non-competitive activation towards the human 5-LOX activator adenosine triphosphate (ATP) and non-essential mixed type activation against the substrate linoleic acid, while having no effect on the conversion of the substrate arachidonic acid. The kinetic analysis demonstrated a non-essential activation of the linoleic acid conversion with a KA of 8.65 μM, αKA of 0.38 μM and a β value of 1.76. It is also of interest that a comparable derivative 23d showed a mixed type inhibition for linoleic acid conversion. These observations indicate the presence of an allosteric binding site in human 5-LOX distinct from the ATP binding site. The activatory and inhibitory behavior of 23a and 23d on the conversion of linoleic compared to arachidonic acid are rationalized by docking studies, which suggest that the activator 23a stabilizes linoleic acid, whereas the larger inhibitor 23d blocks the enzyme active site. PMID:24231650

  7. The retinoic acid derivative, ABPN, inhibits pancreatic cancer through induction of Nrdp1

    PubMed Central

    Byun, Sanguine; Shin, Seung Ho; Lee, Eunjung; Lee, Jihoon; Lee, Sung-Young; Farrand, Lee; Jung, Sung Keun; Cho, Yong-Yeon; Um, Soo-Jong; Sin, Hong-Sig; Kwon, Youn-Ja; Zhang, Chengjuan; Tsang, Benjamin K.; Bode, Ann M.; Lee, Hyong Joo; Lee, Ki Won; Dong, Zigang

    2015-01-01

    Combination chemotherapy for the treatment of pancreatic cancer commonly employs gemcitabine with an EGFR inhibitor such as erlotinib. Here, we show that the retinoic acid derivative, ABPN, exhibits more potent anticancer effects than erlotinib, while exhibiting less toxicity toward noncancerous human control cells. Low micromolar concentrations of ABPN induced apoptosis in BxPC3 and HPAC pancreatic cancer cell lines, concomitant with a reduction in phosphorylated EGFR as well as decreased ErbB3, Met and BRUCE protein levels. The degradation of ErbB3 is a result of proteasomal degradation, possibly due to the ABPN-dependent upregulation of Nrdp1. Administration of ABPN showed significant reductions in tumor size when tested using a mouse xenograft model, with higher potency than erlotinib at the same concentration. Analysis of the tumors demonstrated that ABPN treatment suppressed ErbB3 and Met and induced Nrdp1 in vivo. The data suggest that ABPN may be more suitable in combination chemotherapy with gemcitabine than the more widely used EGFR inhibitor, erlotinib. PMID:26464195

  8. The retinoic acid derivative, ABPN, inhibits pancreatic cancer through induction of Nrdp1.

    PubMed

    Byun, Sanguine; Shin, Seung Ho; Lee, Eunjung; Lee, Jihoon; Lee, Sung-Young; Farrand, Lee; Jung, Sung Keun; Cho, Yong-Yeon; Um, Soo-Jong; Sin, Hong-Sig; Kwon, Youn-Ja; Zhang, Chengjuan; Tsang, Benjamin K; Bode, Ann M; Lee, Hyong Joo; Lee, Ki Won; Dong, Zigang

    2015-12-01

    Combination chemotherapy for the treatment of pancreatic cancer commonly employs gemcitabine with an EGFR inhibitor such as erlotinib. Here, we show that the retinoic acid derivative, ABPN, exhibits more potent anticancer effects than erlotinib, while exhibiting less toxicity toward noncancerous human control cells. Low micromolar concentrations of ABPN induced apoptosis in BxPC3 and HPAC pancreatic cancer cell lines, concomitant with a reduction in phosphorylated EGFR as well as decreased ErbB3, Met and BRUCE protein levels. The degradation of ErbB3 is a result of proteasomal degradation, possibly due to the ABPN-dependent upregulation of Nrdp1. Administration of ABPN showed significant reductions in tumor size when tested using a mouse xenograft model, with higher potency than erlotinib at the same concentration. Analysis of the tumors demonstrated that ABPN treatment suppressed ErbB3 and Met and induced Nrdp1 in vivo. The data suggest that ABPN may be more suitable in combination chemotherapy with gemcitabine than the more widely used EGFR inhibitor, erlotinib.

  9. Hydroxycinnamic Acid Derivatives Obtained from a Commercial Crataegus Extract and from Authentic Crataegus spp.§

    PubMed Central

    Kuczkowiak, Ulrich; Petereit, Frank; Nahrstedt, Adolf

    2014-01-01

    Abstract Eleven hydroxycinnamic acid derivatives were isolated from a 70% methanolic Crataegus extract (Crataegi folium cum flore) and partly verified and quantified for individual Crataegus species (C. laevigata, C. monogyna, C. nigra, C. pentagyna) by HPLC: 3-O-(E)-p-coumaroylquinic acid (1), 5-O-(E)-p-coumaroyl-quinic acid (2), 4-O-(E)-p-coumaroylquinic acid (3), 3-O-(E)-caffeoylquinic acid (4), 4-O-(E)-caffeoylquinic acid (5), 5-O-(E)-caffeoylquinic acid (6), 3,5-di-O-(E)-caffeoylquinic acid (7), 4,5-di-O-(E)-caffeoylquinic acid (8), (-)-2-O-(E)-caffeoyl-L-threonic acid (9), (-)-4-O-(E)-caffeoyl-L-threonic acid (10), and (-)-4-O-(E)-p-coumaroyl-L-threonic acid (11). Further, (-)-2-O-(E)-caffeoyl-D-malic acid (12) was isolated from C. submollis and also identified for C. pentagyna and C. nigra by co-chromatography. The isolates 10 and 11 were not found in the authentic fresh specimen, indicating that they may be formed during extraction by acyl migration from the 2-O-acylderivatives. Also, 9 and 11 are described here for the first time. All structures were assigned on the basis of their spectroscopic data (1H-, 13C-NMR, MS, optical rotation). PMID:26171328

  10. Hydrodecarboxylation of Carboxylic and Malonic Acid Derivatives via Organic Photoredox Catalysis: Substrate Scope and Mechanistic Insight.

    PubMed

    Griffin, Jeremy D; Zeller, Mary A; Nicewicz, David A

    2015-09-09

    A direct, catalytic hydrodecarboxylation of primary, secondary, and tertiary carboxylic acids is reported. The catalytic system consists of a Fukuzumi acridinium photooxidant with phenyldisulfide acting as a redox-active cocatalyst. Substoichiometric quantities of Hünig's base are used to reveal the carboxylate. Use of trifluoroethanol as a solvent allowed for significant improvements in substrate compatibilities, as the method reported is not limited to carboxylic acids bearing α heteroatoms or phenyl substitution. This method has been applied to the direct double decarboxylation of malonic acid derivatives, which allows for the convenient use of dimethyl malonate as a methylene synthon. Kinetic analysis of the reaction is presented showing a lack of a kinetic isotope effect when generating deuterothiophenol in situ as a hydrogen atom donor. Further kinetic analysis demonstrated first-order kinetics with respect to the carboxylate, while the reaction is zero-order in acridinium catalyst, consistent with another finding suggesting the reaction is light limiting and carboxylate oxidation is likely turnover limiting. Stern-Volmer analysis was carried out in order to determine the efficiency for the carboxylates to quench the acridinium excited state.

  11. Dehydroabietic Acid Derivative QC2 Induces Oncosis in Hepatocellular Carcinoma Cells

    PubMed Central

    Zhang, Guang; Jiang, Chunping; Wang, Zhongxia; Chen, Weibo; Gu, Wen; Ding, Yitao

    2014-01-01

    Aim. Rosin, the traditional Chinese medicine, is reported to be able to inhibit skin cancer cell lines. In this report, we investigate the inhibitory effect against HCC cells of QC2, the derivative of rosin's main components dehydroabietic acid. Methods. MTT assay was used to determine the cytotoxicity of QC2. Morphological changes were observed by time-lapse microscopy and transmission electron microscopy and the cytoskeleton changes were observed by laser-scanning confocal microscopy. Cytomembrane integrity and organelles damage were confirmed by detection of the reactive oxygen (ROS), lactate dehydrogenase (LDH), and mitochondrial membrane potential (Δψm). The underlying mechanism was manifested by Western blotting. The oncotic cell death was further confirmed by detection of oncosis related protein calpain. Results. Swelling cell type and destroyed cytoskeleton were observed in QC2-treated HCC cells. Organelle damage was visualized by transmission electron microscopy. The detection of ROS accumulation, increased LDH release, and decreased ATP and Δψm confirmed the cell death. The oncotic related protein calpain was found to increase time-dependently in QC2-treated HCC cells, while its inhibitor PD150606 attenuated the cytotoxicity. Conclusions. Dehydroabietic acid derivative QC2 activated oncosis related protein calpain to induce the damage of cytomembrane and organelles which finally lead to oncosis in HCC cells. PMID:25110686

  12. Green Synthesis and Urease Inhibitory Activity of Spiro-Pyrimidinethiones/Spiro-Pyrimidinones-Barbituric Acid Derivatives

    PubMed Central

    Mohammadi Ziarani, Ghodsi; Asadi, Shima; Faramarzi, Sakineh; Amanlou, Massoud

    2015-01-01

    Sulfonic acid functionalized SBA-15 (SBA-Pr-SO3H) with pore size 6 nm as an efficient heterogeneous nanoporous solid acid catalyst exhibited good catalytic activity in the Biginelli-like reaction in the synthesis of spiroheterobicyclic rings with good yield and good recyclability. Spiro-pyrimidinethiones/spiro-pyrimidinones-barbituric acid derivatives were synthesized in a simple and efficient method using the one-pot three-component reaction of a cyclic 1,3- dicarbonyl compounds (barbituric acid), an aromatic aldehyde and urea or thiourea in the presence of nanoporous silica SBA-Pr-SO3H under solvent free conditions. Urease inhibitory activity of spiro compounds were tested against Jack bean urease using Berthelot alkaline phenol–hypochlorite method. Five of 13 compounds were inhibitor and two of them were enzyme activators. Analysis of the docking results showed that, in most of the spiro molecules, one of the carbonyl groups is coordinated with both nickel atoms, while the other one is involved in the formation of hydrogen bonds with important active-site residues. The effect of inserting two methyl groups on N atoms of barbiturate ring, S substituted, ortho, meta and para substituted compounds were investigated too. PMID:26664377

  13. [Experimental study of 3-oxypiridine and succinic acid derivates antidepressant activity in mice].

    PubMed

    Volchegorskiĭ, I A; Miroshnichenko, I Iu; Rassokhina, L M; Faĭzullin, R M

    2013-01-01

    Effect of Russian 3-oxypiridine and succinic acid derivatives (emoxipin, reamberin and mexidol) on duration of behavioral despair in mice in forced swimming test (by Porsolot) and tail suspension test (by Steru) was investigated. In addition impact assessment of studied medicinal products (MP) on animals' behavior in open field test was performed. Amitriptyline and alpha-lipoic acid were used as reference drugs. It was determined that single delivery of all studied drugs in optimal doses eqvivalent to therapeutic range for human reduces lasting of behavioral despair in Porsolot and Steru tests. This effect of reamberin, mexidol and alpha-lipoic acid indicates their antidepressant action unrelated to stimulatory activity, as far as these MPs like amitriptyline show sedative action in open field test. Reduction of behavioral despair due to effect of emoxipin in relative low doses was associated with increase of mice activity in open field test and so it can't be considered to be antidepressant action per se. Increase of emoxipin dose leads to progressive decrease of its stimulatory effect impact in behavioral despair reduction and induce antidepressant effect in the setting of sedation.

  14. [Antihypoxic effect of 3-hydroxypyridine and succinic acid derivatives and their nootropic action in alloxan diabetes].

    PubMed

    Volchegorskiĭ, I A; Rassokhina, L M; Miroshnichenko, I Iu

    2011-01-01

    Relationship between the antihypoxic effect of 3-hydroxypyridine and succinic acid derivatives (emoxipine, reamberin and mexidol) and their effect on conditional learning, glycemia, and lipidemia was studied in rats with alloxan-induced diabetes. In parallel, the analogous relationship was investigated for alpha-lipoic acid that is regarded as a "gold standard" in treatment of diabetic neuropathy. It was established that single administration of emoxipine and mexidol in mice in doses equivalent to therapeutic-range doses in humans produces antihypoxic effect manifested by increased resistance to acute hypoxic hypoxia in test animals. Alpha-lipoic acid is inferior to emoxipin and mexidol in the degree of antihypoxic action. Reamberin does not exhibit this effect. The introduction of emoxipin, reamberin, mexidol, and alpha-lipoic acid in rats with alloxan diabetes during 7 or 14 days in doses equivalent to therapeutic-range doses in humans corrects conditional learning disorders in direct relationship with the antihypoxic activity of these drugs. The development of the nootropic effect of emoxipin, mexidol, and alpha-lipoic acid is related to a decrease in hyperglycemia and hyperlipidemia in rats with alloxan diabetes. The nootropic action of reamberin is accompanied by a transient hypoglycemizing effect and aggravation of dyslipidemic disorders. The antihypoxic activity of investigated drugs determines the direction and expression of their lipidemic effect, but is not correlated with the hypoglycemizing action these drugs on test animals with alloxan diabetes.

  15. Mathematical models of antisickling activities of benzoic acid derivatives on red blood cells of sicklers.

    PubMed

    Fasanmade, A A; Olaniyi, A A; Ab-Yisak, W

    1994-12-01

    A classical drug design technique based on the quantitative structure--activity relationship is applied to a series of synthetic benzoic acid derivatives. Some of the active derivatives tested include; p-toluic acid, p-dimethyl-amino benzoic acid, p-fluorobenzoic acid, p-chlorobenzoic acid, m-chlorobenzoic acid, p-bromobenzoic acid, p-nitrobenzoic acid, and p-iodobenzoic acid. The Hansch lipophilicity, pi, and the Hammett electronic parameters; sigma, were found to predict activities of the agents on the reversal of sickle-shaped deoxygenated sickle red blood cell to normal morphology. A series of equations correlating the biological activities with the structure of the tested compounds were analysed using multiple regression techniques. The most applicable of the equations was found to be; Log BR = -A sigma + B pi--C pi 2 + K Interpretation of this equation in terms of the biological action of the drugs on red blood cells was attempted. In designing a potent antisickling agent, the benzoic acid should have strong electron donating group(s) attached to the benzene ring and should be made averagely lipophilic to satisfy the relationship derived in this study.

  16. Synthesis, characterization, and computational study of the supramolecular arrangement of a novel cinnamic acid derivative.

    PubMed

    Oliveira, S S; Santin, L G; Almeida, L R; Malaspina, L A; Lariucci, C; Silva, J F; Fernandes, W B; Aquino, G L B; Gargano, R; Camargo, A J; Napolitano, H B

    2017-02-01

    In this work, we present the synthesis, characterization, and computational study of the supramolecular arrangement of a new cinnamic acid derivative: ethyl-(2E)-3-(4-hydroxy-3,5-dimethoxyphenyl)-prop-2-enoate (EHD). Single crystals of EHD were obtained using ethyl ether as solvent and a slow evaporation technique. Its crystallographic structure, derived from X-ray diffraction experiments, includes a disordered water molecule on the EHD supramolecular structure. This water molecule participates in four O-H···O hydrogen bonds, which are arranged as a centrosymmetric H-bond array with the water at the center. Electronic and structural properties of the isolated EHD molecule and of the EHD molecule in the presence of one water molecule were calculated at the B3LYP/6-311++G(2d,2p) level of theory. These calculations show that the HOMO-LUMO energy gap of EHD decreases upon the introduction of the water molecule, suggesting that EHD becomes a stronger electron acceptor. These results indicate that the water molecule helps to stabilize the crystal structure in this system containing unequal numbers of acceptor and donor atoms. The supramolecular synthon involving the disordered water molecule and the supramolecular features presented here provide new possibilities in the design of functional materials and should also help us to gain a deeper understanding of the processes by which molecules recognize biological targets.

  17. Amphipathic β2,2-Amino Acid Derivatives Suppress Infectivity and Disrupt the Intracellular Replication Cycle of Chlamydia pneumoniae

    PubMed Central

    Tiirola, Terttu M.; Strøm, Morten B.; Vuorela, Pia M.

    2016-01-01

    We demonstrate in the current work that small cationic antimicrobial β2,2-amino acid derivatives (Mw < 500 Da) are highly potent against Chlamydia pneumoniae at clinical relevant concentrations (< 5 μM, i.e. < 3.4 μg/mL). C. pneumoniae is an atypical respiratory pathogen associated with frequent treatment failures and persistent infections. This gram-negative bacterium has a biphasic life cycle as infectious elementary bodies and proliferating reticulate bodies, and efficient treatment is challenging because of its long and obligate intracellular replication cycle within specialized inclusion vacuoles. Chlamydicidal effect of the β2,2-amino acid derivatives in infected human epithelial cells was confirmed by transmission electron microscopy. Images of infected host cells treated with our lead derivative A2 revealed affected chlamydial inclusion vacuoles 24 hours post infection. Only remnants of elementary and reticulate bodies were detected at later time points. Neither the EM studies nor resazurin-based cell viability assays showed toxic effects on uninfected host cells or cell organelles after A2 treatment. Besides the effects on early intracellular inclusion vacuoles, the ability of these β2,2-amino acid derivatives to suppress Chlamydia pneumoniae infectivity upon treatment of elementary bodies suggested also a direct interaction with bacterial membranes. Synthetic β2,2-amino acid derivatives that target C. pneumoniae represent promising lead molecules for development of antimicrobial agents against this hard-to-treat intracellular pathogen. PMID:27280777

  18. A general approach to quantification of hydroxycinnamic acid derivatives and flavones, flavonols, and their glycosides by UV spectrophotometry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A general method was developed for the quantification of hydroxycinnamic acid derivatives and flavones, flavonols, and their glycosides based on the UV molar relative response factors (MRRF) of the standards. Each of these phenolic compounds contains a cinnamoyl structure and has a maximum absorban...

  19. [Enzymatic formation of a cis,cis-muconic acid derivative using pyrazon-degrading bacteria (author's transl)].

    PubMed

    Blobel, F; Eberspächer, J; Haug, S; Lingens, F

    1976-01-01

    The cis,cis-muconic acid derivative of pyrazon, which was formerly isolated from the medium of pyrazon-degrading bacteria, was formed enzymatically by incubation of the catechol derivative of pyrazon with partially purified ortho pyrocatechase from pyrazon-degrading bacteria.

  20. Engineering alfalfa to accumulate useful caffeic acid derivatives and characterization of hydroxycinnamoyl-CoA transferases from legumes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Some forages crops, such as red clover, accumulate high levels of caffeic acid derivatives. Oxidation of these o-diphenols to quinones by endogenous polyphenol oxidases (PPOs) and the subsequent reactions of these quinones (probably with endogenous plant proteases) result in a significant reduction ...

  1. Synthesis and biological activity evaluation of novel amino acid derivatives as potential elicitors against Tomato yellow leaf curl virus.

    PubMed

    Deng, Yufang; He, Shun; Geng, Qianqian; Duan, Yongheng; Guo, Mingcheng; Li, Jianqiang; Cao, Yongsong

    2015-12-01

    Disease caused by Tomato yellow leaf curl virus (TYLCV) brings serious production losses of cultivated tomato worldwide. In our previous study, two novel amino acid derivatives exerted satisfactory antiviral activities against TYLCV. In this study, the variation of TYLCV, the transcriptional expression level of Ty-1 and the enzyme activities of POD and PPO in tomato were monitored after treatment with two amino acid derivatives to illustrate the antiviral mechanism. The results showed the symptom severity caused by TYLCV was reduced significantly by two compounds and was associated with the inhibition of viral DNA level at the early stage. Among three levels of concentration, the highest inhibition rate of CNBF-His was 40.66% at 1000 mg/L, for CNBF-Asn, the highest inhibition rate was 36.26% at 2000 mg/L 30 days post-inoculation. Two compounds could also enhance the activities of PPO and POD and the transcriptional expression level of Ty-1 which correlates with plant resistance in tomato. In the field test, two compounds increased the yields of tomato and the maximum increase of yield was 37.66%. This is the first report of novel amino acid derivatives inducing resistance in tomato plant against TYLCV. It is suggested that amino acid derivatives have the potential to be an effective approach against TYLCV in tomato plant.

  2. Molecular structure and spectroscopic investigations combined with hypoglycemic/anticancer and docking studies of a new barbituric acid derivative

    NASA Astrophysics Data System (ADS)

    Barakat, Assem; Soliman, Saied M.; Elshaier, Yaseen A. M. M.; Ali, M.; Al-Majid, Abdullah Mohammed; Ghabbour, Hazem A.

    2017-04-01

    The one-pot synthesis reaction of barbituric acid derivative, 1,3-cyclohexandione, and 4-fluorobenzaldehyde in water mediated by NHEt2 as base afforded 4 with excellent yield. The synthesized compound was characterized by spectrophotometric tools as well as X-ray single crystal diffraction technique. The stability of the nine possible isomers of the synthesized compound was studied using the B3LYP method and 6-31G(d,p) basis set. The electronic and spectroscopic properties of the most stable isomer were predicted. The UV-Vis absorption spectrum displayed two bands at 203 and 257 nm in the solvent chloroform. The latter was calculated at 235.6 nm (f = 0.1995) in the gas phase due to H-2→L (42%) and H-1→L+2 (14%) excitations. In solution, using chloroform as a solvent, a slight bathochromic shift to 237.6 nm with an increase in the absorption intensity (f = 0.2898) was predicted. The molecular orbital energy level diagram of this transition band was characterized mainly by π-π* transitions. The 13C and 1H NMR chemical shifts correlated well with the experimental data. The correlations had higher correlation coefficients (R2) when solvent effects were considered. The atomic charges were calculated using natural population analysis and the charged regions were presented using a molecular electrostatic potential (MEP) map. The synthesized compound was examined as a hypoglycemic agent via inhibition of α-glucosidase and β-glucuronidase enzymes. Its inhibitory activity against α-glucosidase was 10 times greater than the inhibitory activity of the standard drug acarbose (IC50 77.9 ± 0.3 μM and 840 ± 1.73 μM, respectively). Moreover, the target compound was evaluated for anticancer activity against MCF-7, H460, 3T3, and Hela cell lines. It demonstrated inhibitory activity against the MCF-7 and H460 cell lines with IC50 5.80 ± 0.12 and 19.6 ± 0.5 μM, respectively, in comparison to doxorubicin. The docking study was performed using the OpenEye program.

  3. C13C4.5/Spinster, an evolutionarily conserved protein that regulates fertility in C. elegans through a lysosome-mediated lipid metabolism process.

    PubMed

    Han, Mei; Chang, Hao; Zhang, Peng; Chen, Tao; Zhao, Yanhua; Zhang, Yongdeng; Liu, Pingsheng; Xu, Tao; Xu, Pingyong

    2013-05-01

    Lipid droplets, which are conserved across almost all species, are cytoplasmic organelles used to store neutral lipids. Identification of lipid droplet regulators will be conducive to resolving obesity and other fat-associated diseases. In this paper, we selected 11 candidates that might be associated with lipid metabolism in Caenorhabditis elegans. Using a BODIPY 493/503-based flow cytometry screen, 6 negative and 3 positive regulators of fat content were identified. We selected one negative regulator of lipid content, C13C4.5, for future study. C13C4.5 was mainly expressed in the worm intestine. We found that this gene was important for maintaining the metabolism of lipid droplets. Biochemical results revealed that 50% of triacylglycerol (TAG) was lost in C13C4.5 knockout worms. Stimulated Raman scattering (SRS) signals in C13C4.5 mutants showed only 49.6% of the fat content in the proximal intestinal region and 86.3% in the distal intestinal region compared with wild type animals. The mean values of lipid droplet size and intensity in C13C4.5 knockout animals were found to be significantly decreased compared with those in wild type worms. The LMP-1-labeled membrane structures in worm intestines were also enlarged in C13C4.5 mutant animals. Finally, fertility defects were found in C13C4.5(ok2087) mutants. Taken together, these results indicate that C13C4.5 may regulate the fertility of C. elegans by changing the size and fat content of lipid droplets by interfering with lysosomal morphology and function.

  4. Microbial engineering for the production of fatty acids and fatty acid derivatives

    DOEpatents

    Stephanopoulos, Gregory; Abidi, Syed Hussain Imam

    2014-07-01

    Some aspects of this invention relate to methods useful for the conversion of a carbon source to a biofuel or biofuel precursor using engineered microbes. Some aspects of this invention relate to the discovery of a key regulator of lipid metabolism in microbes. Some aspects of this invention relate to engineered microbes for biofuel or biofuel precursor production.

  5. Solid Phase Micro-extraction (SPME) with In Situ Transesterification: An Easy Method for the Detection of Non-volatile Fatty Acid Derivatives on the Insect Cuticle.

    PubMed

    Kühbandner, Stephan; Ruther, Joachim

    2015-06-01

    Triacylglycerides (TAGs) and other non-volatile fatty acid derivatives (NFADs) occur in large amounts in the internal tissues of insects, but their presence on the insect cuticle is controversially discussed. Most studies investigating cuticular lipids of insects involve solvent extraction, which implies the risk of extracting lipids from internal tissues. Here, we present a new method that overcomes this problem. The method employs solid phase micro-extraction (SPME) to sample NFADs by rubbing the SPME fiber over the insect cuticle. Subsequently, the sampled NFADs are transesterified in situ with trimethyl sulfonium hydroxide (TMSH) into more volatile fatty acid methyl esters (FAMEs), which can be analyzed by standard GC/MS. We performed two types of control experiments to enable significant conclusions: (1) to rule out contamination of the GC/MS system with NFADs, and (2) to exclude the presence of free fatty acids on the insect cuticle, which would also furnish FAMEs after TMSH treatment, and thus might simulate the presence of NFADs. In combination with these two essential control experiments, the described SPME technique can be used to detect TAGs and/or other NFADs on the insect cuticle. We analyzed six insect species from four insect orders with our method and compared the results with conventional solvent extraction followed by ex situ transesterification. Several fatty acids typically found as constituents of TAGs were detected by the SPME method on the cuticle of all species analyzed. A comparison of the two methods revealed differences in the fatty acid compositions of the samples. Saturated fatty acids showed by trend higher relative abundances when sampled with the SPME method, while several minor FAMEs were detected only in the solvent extracts. Our study suggests that TAGs and maybe other NFADs are far more common on the insect cuticle than usually thought.

  6. Structural Investigation for Optimization of Anthranilic Acid Derivatives as Partial FXR Agonists by in Silico Approaches

    PubMed Central

    Chen, Meimei; Yang, Xuemei; Lai, Xinmei; Kang, Jie; Gan, Huijuan; Gao, Yuxing

    2016-01-01

    In this paper, a three level in silico approach was applied to investigate some important structural and physicochemical aspects of a series of anthranilic acid derivatives (AAD) newly identified as potent partial farnesoid X receptor (FXR) agonists. Initially, both two and three-dimensional quantitative structure activity relationship (2D- and 3D-QSAR) studies were performed based on such AAD by a stepwise technology combined with multiple linear regression and comparative molecular field analysis. The obtained 2D-QSAR model gave a high predictive ability (R2train = 0.935, R2test = 0.902, Q2LOO = 0.899). It also uncovered that number of rotatable single bonds (b_rotN), relative negative partial charges (RPC−), oprea's lead-like (opr_leadlike), subdivided van der Waal’s surface area (SlogP_VSA2) and accessible surface area (ASA) were important features in defining activity. Additionally, the derived3D-QSAR model presented a higher predictive ability (R2train = 0.944, R2test = 0.892, Q2LOO = 0.802). Meanwhile, the derived contour maps from the 3D-QSAR model revealed the significant structural features (steric and electronic effects) required for improving FXR agonist activity. Finally, nine newly designed AAD with higher predicted EC50 values than the known template compound were docked into the FXR active site. The excellent molecular binding patterns of these molecules also suggested that they can be robust and potent partial FXR agonists in agreement with the QSAR results. Overall, these derived models may help to identify and design novel AAD with better FXR agonist activity. PMID:27070594

  7. Protective effect of bile acid derivatives in phalloidin-induced rat liver toxicity

    SciTech Connect

    Herraez, Elisa; Macias, Rocio I.R.; Vazquez-Tato, Jose; Hierro, Carlos; Monte, Maria J.; Marin, Jose J.G.

    2009-08-15

    Phalloidin causes severe liver damage characterized by marked cholestasis, which is due in part to irreversible polymerization of actin filaments. Liver uptake of this toxin through the transporter OATP1B1 is inhibited by the bile acid derivative BALU-1, which does not inhibit the sodium-dependent bile acid transporter NTCP. The aim of the present study was to investigate whether BALU-1 prevents liver uptake of phalloidin without impairing endogenous bile acid handling and hence may have protective effects against the hepatotoxicity induced by this toxin. In anaesthetized rats, i.v. administration of BALU-1 increased bile flow more than taurocholic acid (TCA). Phalloidin administration decreased basal (- 60%) and TCA-stimulated bile flow (- 55%) without impairing bile acid output. Phalloidin-induced cholestasis was accompanied by liver necrosis, nephrotoxicity and haematuria. In BALU-1-treated animals, phalloidin-induced cholestasis was partially prevented. Moreover haematuria was not observed, which was consistent with histological evidences of BALU-1-prevented injury of liver and kidney tissue. HPLC-MS/MS analysis revealed that BALU-1 was secreted in bile mainly in non-conjugated form, although a small proportion (< 5%) of tauro-BALU-1 was detected. BALU-1 did not inhibit the biliary secretion of endogenous bile acids. When highly choleretic bile acids, - ursodeoxycholic (UDCA) and dehydrocholic acid (DHCA) - were administered, they were found less efficient than BALU-1 in preventing phalloidin-induced cholestasis. Biliary phalloidin elimination was low but it was increased by BALU-1 > TCA > DHCA > UDCA. In conclusion, BALU-1 is able to protect against phalloidin-induced hepatotoxicity, probably due to an inhibition of the liver uptake and an enhanced biliary secretion of this toxin.

  8. Hepatic fibroblast growth factor 21 is regulated by PPARalpha and is a key mediator of hepatic lipid metabolism in ketotic states.

    PubMed

    Badman, Michael K; Pissios, Pavlos; Kennedy, Adam R; Koukos, George; Flier, Jeffrey S; Maratos-Flier, Eleftheria

    2007-06-01

    Mice fed a high-fat, low-carbohydrate ketogenic diet (KD) exhibit marked changes in hepatic metabolism and energy homeostasis. Here, we identify liver-derived fibroblast growth factor 21 (FGF21) as an endocrine regulator of the ketotic state. Hepatic expression and circulating levels of FGF21 are induced by both KD and fasting, are rapidly suppressed by refeeding, and are in large part downstream of PPARalpha. Importantly, adenoviral knockdown of hepatic FGF21 in KD-fed mice causes fatty liver, lipemia, and reduced serum ketones, due at least in part to altered expression of key genes governing lipid and ketone metabolism. Hence, induction of FGF21 in liver is required for the normal activation of hepatic lipid oxidation, triglyceride clearance, and ketogenesis induced by KD. These findings identify hepatic FGF21 as a critical regulator of lipid homeostasis and identify a physiological role for this hepatic hormone.

  9. Rhodium-catalyzed asymmetric addition of arylboronic acids to cyclic N-sulfonyl ketimines towards the synthesis of α,α-diaryl-α-amino acid derivatives.

    PubMed

    Takechi, Ryosuke; Nishimura, Takahiro

    2015-05-07

    Rhodium/chiral diene complex-catalyzed asymmetric addition of arylboronic acids to cyclic ketimines having an ester group proceeded to give the corresponding α-amino acid derivatives in high yields with high enantioselectivity. The cyclic amino acid derivative was transformed into a linear α,α-diaryl-substituted α-N-methylamino acid ester.

  10. Adenylyl cyclase type 6 overexpression selectively enhances beta-adrenergic and prostacyclin receptor-mediated inhibition of cardiac fibroblast function because of colocalization in lipid rafts.

    PubMed

    Liu, Xiaoqiu; Thangavel, Muthusamy; Sun, Shu Qiang; Kaminsky, Joseph; Mahautmr, Penden; Stitham, Jeremiah; Hwa, John; Ostrom, Rennolds S

    2008-06-01

    Cardiac fibroblasts produce and degrade extracellular matrix and are critical in regulating cardiac remodeling and hypertrophy. Fibroblasts are activated by factors such as transforming growth factor beta and inhibited by agents that elevate 3',5'-cyclic adenosine monophosphate (cAMP) levels. cAMP signal generation and response is known to be compartmentalized in many cell types in part through the colocalization of receptors and specific adenylyl cyclase isoforms in lipid rafts and caveolae. The present study sought to define the localization of key G protein-coupled receptors with adenylyl cyclase type 6 (AC6) in lipid rafts of rat cardiac fibroblasts and to determine if this colocalization was functionally relevant. We found that cardiac fibroblasts produce cAMP in response to agonists for beta-adrenergic (isoproterenol), prostaglandin EP2 (butaprost), adenosine (adenosine-5'-N-ethylcarboxamide, NECA), and prostacyclin (beraprost) receptors. Overexpression of AC6 increased cAMP production stimulated by isoproterenol and beraprost but not by butaprost or NECA. A key function of fibroblasts is the production of collagen. Isoproterenol- and beraprostmediated inhibition of collagen synthesis was also enhanced by AC6 overexpression, while inhibition by butaprost and NECA were unaltered. Lipid raft fractions from cardiac fibroblasts contain the preponderance of beta-adrenergic receptors and AC6 but exclude EP2 receptors. While we could not determine the localization of native prostacyclin receptors, we were able to determine that epitope-tagged prostanoid IP receptors (IPR) expressed in COS7 cells did localize, in part, in lipid raft fractions. These findings indicate that IP receptors are expressed in lipid rafts and can activate raft-localized AC isoforms. AC6 is completely compartmentized in lipid raft domains where it is activated solely by coresident G protein-coupled receptors to regulate cardiac fibroblast function.

  11. Harnessing Yeast Peroxisomes for Biosynthesis of Fatty-Acid-Derived Biofuels and Chemicals with Relieved Side-Pathway Competition.

    PubMed

    Zhou, Yongjin J; Buijs, Nicolaas A; Zhu, Zhiwei; Gómez, Diego Orol; Boonsombuti, Akarin; Siewers, Verena; Nielsen, Jens

    2016-11-30

    Establishing efficient synthetic pathways for microbial production of biochemicals is often hampered by competing pathways and/or insufficient precursor supply. Compartmentalization in cellular organelles can isolate synthetic pathways from competing pathways, and provide a compact and suitable environment for biosynthesis. Peroxisomes are cellular organelles where fatty acids are degraded, a process that is inhibited under typical fermentation conditions making them an interesting workhouse for production of fatty-acid-derived molecules. Here, we show that targeting synthetic pathways to peroxisomes can increase the production of fatty-acid-derived fatty alcohols, alkanes and olefins up to 700%. In addition, we demonstrate that biosynthesis of these chemicals in the peroxisomes results in significantly decreased accumulation of byproducts formed by competing enzymes. We further demonstrate that production can be enhanced up to 3-fold by increasing the peroxisome population. The strategies described here could be used for production of other chemicals, especially acyl-CoA-derived molecules.

  12. Synthesis, cytotoxic evaluation and in silico pharmacokinetic prediction of some benzo[a]phenazine-5-sulfonic acid derivatives.

    PubMed

    Hari Narayana Moorthy, N S; Karthikeyan, C; Trivedi, Piyush

    2009-11-01

    Cancer is one of the life threatening diseases and the development of novel anticancer molecules is limited by many reasons. In the present investigation, some novel benzo[a]phenazine-5-sulfonic acid derivatives as DNA intercalator was designed with optimized pharmacokinetic features for cancer treatment. The compounds with desired pharmacokinetic profile were synthesized and structurally characterized. Cytotoxic activity study against HL-60 tumor cell lines shows that 10-dimethyl carboxamido derivative of benzo[a]phenazine-5-sulfonic acid is found to be the most active in the series with cytotoxic activity (IC(50) = 19 microM) comparable to cisplatin (IC(50) = 7 microM). The study concluded that the novel benzo[a]phenazine-5-sulfonic acid derivatives were found to have enhanced DNA binding affinity and exhibited significant activity in vitro against HL-60 cell lines. This work will also guide for further development of effective DNA intercalators for cancer treatment.

  13. Synthesis and biological relationships of 3',6-substituted 2-phenyl-4-quinolone-3-carboxylic acid derivatives as antimitotic agents.

    PubMed

    Lai, Ya-Yun; Huang, Li-Jiau; Lee, Kuo-Hsiung; Xiao, Zhiyan; Bastow, Kenneth F; Yamori, Takao; Kuo, Sheng-Chu

    2005-01-03

    As part of a continuing search for potential anticancer drug candidates in the 2-phenyl-4-quinolone series, 3',6-substituted 2-phenyl-4-quinolone-3-carboxylic acid derivatives and their salts were synthesized and evaluated. Preliminary screening showed that carboxylic acid analogs containing a m-fluoro substituted 2-phenyl group displayed the highest in vitro anticancer activity. Activity decreased significantly if a chlorine or methoxy group replaced the fluorine atom. 3'-Fluoro-6-methoxy-2-phenyl-4-quinolone-3-carboxylic acid (68) had the highest in vitro cytotoxic activity among all tested carboxylic acid derivatives and their salts. The mechanism of action may be similar, but not identical, to that of tubulin binding drugs, such as navelbine and taxol. Compound 68 merits further investigation as a novel hydrophilic antimitotic agent.

  14. Use of humic acids derived from peat and lignite as phenanthrene sorbents

    NASA Astrophysics Data System (ADS)

    Sofikitis, Elias; Giannouli, Andriana; Kalaitzidis, Stavros; Christanis, Kimon; Karapanagioti, Hrissi K.; Papanicolaou, Cassiani

    2015-04-01

    A broad range of materials is being applied for environmental remediation of water, among them sorbents such as humic acids. Being natural substances, the extraction and purification of humic acids might be cheaper than the production of synthetic sorbents. Having higher absorbing capacity than most of the sorbents used to date, humic acids have a competitive advantage against commonly used sorbents such as active charcoals and biochar. Humic acids are "complex colloidal super-mixtures" that are characterized by their functional groups. Therefore, composition and molecular formula can vary depending on the properties of the parent material. The aim of this project was (a) to study the sorption capacity of humic acids derived from peat and lignite samples picked up from deposits spread throughout Greece and (b) to compare the results with these of the parent materials. This comparison provides an insight to which matrix samples are suitable for further chemical treatment for the isolation of humic acids to be used as sorbents. The selected model pollutant was phenanthrene, which is a PAH that consists of three fused benzene rings. Humic acids were extracted according to the methodology proposed by the IHSS, slightly modified, in order to fit better to the properties of organic sediments. Sorption experiments were conducted by mixing 0.004 g of the sorbent (peat or lignite or humic acid) with aqueous solutions of phenanthrene at different concentrations of 30, 50, 100, 300, and 500 μg/L. The results show that phenanthrene sorption is higher for the humic acid than for the original lignite and peat samples. The original samples display higher sorption at the lower phenanthere solutions (30 μg/L; Kd ranges from 15,000 to 47,000 L/kg) than at the higher one (500 μg/L; Kd ranges from 4,100 to 13,000 L/Kg) suggesting non-linear sorption. The humic acids display mainly linear isotherms with Kd ranges from 6,600 to 120,000 L/kg. Concerning the suitability of the studied

  15. Antileishmanial activity of semisynthetic lupane triterpenoids betulin and betulinic acid derivatives: synergistic effects with miltefosine.

    PubMed

    Sousa, Maria C; Varandas, Raquel; Santos, Rita C; Santos-Rosa, Manuel; Alves, Vera; Salvador, Jorge A R

    2014-01-01

    Leishmaniasis is a neglected tropical disease (NTDs), endemic in 88 countries, affecting more than 12 million people. The treatment consists in pentavalent antimony compounds, amphotericin B, pentamidine and miltefosine, among others. However, these current drugs are limited due to their toxicity, development of biological resistance, length of treatment and high cost. Thus, it is important to continue the search for new effective and less toxic treatments. The anti-Leishmania activity of sixteen semisynthetic lupane triterpenoids derivatives of betulin (BT01 to BT09) and betulinic acid (AB10 to AB16) were evaluated. Drug interactions between the active compounds and one current antileishmanial drug, miltefosine, were assessed using the fixed ratio isobologram method. In addition, effects on the cell cycle, apoptosis/necrosis events, morphology and DNA integrity were studied. The derivatives BT06 (3β-Hydroxy-(20R)-lupan-29-oxo-28-yl-1H-imidazole-1-carboxylate) and AB13 (28-(1H-imidazole-1-yl)-3,28-dioxo-lup-1,20(29)-dien-2-yl-1H-imidazole-1-carboxylate) were found to be the most active, with IC50 values of 50.8 µM and 25.8 µM, respectively. Interactions between these two compounds and miltefosine were classified as synergistic, with the most effective association being between AB13 and miltefosine, where decreases of IC50 values to 6 µM were observed, similar to the miltefosine activity alone. AB13 induced significant morphological changes, while both derivatives produced anti-proliferative activity through cell cycle arrest at the G0/G1 phase. Neither of these derivatives induced significant apoptosis/necrosis, as indicated by phosphatidylserine externalization and DNA fragmentation assays. In addition, neither of the derivatives induced death in macrophage cell lines. Thus, they do not present any potential risk of toxicity for the host cells. This study has identified the betulin derivative BT06 and the betulinic acid derivative AB13 as promising molecules

  16. 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

  17. Palladium-catalyzed fluorocarbonylation using N-formylsaccharin as CO source: general access to carboxylic acid derivatives.

    PubMed

    Ueda, Tsuyoshi; Konishi, Hideyuki; Manabe, Kei

    2013-10-18

    N-formylsaccharin, an easily accessible crystalline compound, has been employed as an efficient CO source in Pd-catalyzed fluorocarbonylation of aryl halides to afford the corresponding acyl fluorides in high yields. The reactions use a near-stoichiometric amount of the CO source (1.2 equiv) and tolerate diverse functional groups. The acyl fluorides obtained could be readily transformed into various carboxylic acid derivatives such as carboxylic acid, esters, thioesters, and amides in a one-pot procedure.

  18. Asymmetric Synthesis of an Amino Acid Derivative from Achiral Aroyl Acrylamide by Reversible Michael Addition and Preferential Crystallization.

    PubMed

    Kaji, Yuki; Uemura, Naohiro; Kasashima, Yoshio; Ishikawa, Hiroki; Yoshida, Yasushi; Mino, Takashi; Sakamoto, Masami

    2016-11-07

    Single-handed α-amino acid derivatives were generated from achiral precursors without an external chiral source. Conjugate addition of phenethylamine to an achiral aroyl acrylamide under homogeneous conditions gave the α-amino amides in quantitative yields, which crystallized as a conglomerate of a P21 crystal system. Dynamic preferential crystallization or attrition-enhanced deracemization resulted in the formation of enantiomorphic crystals of 99 % ee.

  19. Sulfotanone, a new alkyl sulfonic acid derivative from Streptomyces sp. IFM 11694 with TRAIL resistance-overcoming activity.

    PubMed

    Abdelfattah, Mohamed S; Ishikawa, Naoki; Karmakar, Utpal K; Ishibashi, Masami

    2016-04-01

    One new alkyl sulfonic acid derivative, sulfotanone (1), and the known panosialin wA (2) were isolated from the methanolic extract of mycelium of Streptomyces sp. 11694. The structure of the new compound (1) was established by a combination of spectroscopic techniques, including HRESIMS, IR, 1D and 2D NMR measurements. Compound 1 (40 µM) in combination with TRAIL showed synergistic activity in sensitizing TRAIL-resistance in human gastric adenocarcinoma cell lines.

  20. FAX1, a Novel Membrane Protein Mediating Plastid Fatty Acid Export

    PubMed Central

    Li, Nannan; Gügel, Irene Luise; Giavalisco, Patrick; Zeisler, Viktoria; Schreiber, Lukas; Soll, Jürgen; Philippar, Katrin

    2015-01-01

    Fatty acid synthesis in plants occurs in plastids, and thus, export for subsequent acyl editing and lipid assembly in the cytosol and endoplasmatic reticulum is required. Yet, the transport mechanism for plastid fatty acids still remains enigmatic. We isolated FAX1 (fatty acid export 1), a novel protein, which inserts into the chloroplast inner envelope by α-helical membrane-spanning domains. Detailed phenotypic and ultrastructural analyses of FAX1 mutants in Arabidopsis thaliana showed that FAX1 function is crucial for biomass production, male fertility and synthesis of fatty acid-derived compounds such as lipids, ketone waxes, or pollen cell wall material. Determination of lipid, fatty acid, and wax contents by mass spectrometry revealed that endoplasmatic reticulum (ER)-derived lipids decreased when FAX1 was missing, but levels of several plastid-produced species increased. FAX1 over-expressing lines showed the opposite behavior, including a pronounced increase of triacyglycerol oils in flowers and leaves. Furthermore, the cuticular layer of stems from fax1 knockout lines was specifically reduced in C29 ketone wax compounds. Differential gene expression in FAX1 mutants as determined by DNA microarray analysis confirmed phenotypes and metabolic imbalances. Since in yeast FAX1 could complement for fatty acid transport, we concluded that FAX1 mediates fatty acid export from plastids. In vertebrates, FAX1 relatives are structurally related, mitochondrial membrane proteins of so-far unknown function. Therefore, this protein family might represent a powerful tool not only to increase lipid/biofuel production in plants but also to explore novel transport systems involved in vertebrate fatty acid and lipid metabolism. PMID:25646734

  1. Anti-Inflammatory Activity of Tanzawaic Acid Derivatives from a Marine-Derived Fungus Penicillium steckii 108YD142

    PubMed Central

    Shin, Hee Jae; Pil, Gam Bang; Heo, Soo-Jin; Lee, Hyi-Seung; Lee, Jong Seok; Lee, Yeon-Ju; Lee, Jihoon; Won, Ho Shik

    2016-01-01

    Chemical investigation of a marine-derived fungus, Penicillium steckii 108YD142, resulted in the discovery of a new tanzawaic acid derivative, tanzawaic acid Q (1), together with four known analogues, tanzawaic acids A (2), C (3), D (4), and K (5). The structures of tanzawaic acid derivatives 1–5 were determined by the detailed analysis of 1D, 2D NMR and LC-MS data, along with chemical methods and literature data analysis. These compounds significantly inhibited nitric oxide (NO) production and the new tanzawaic acid Q (1) inhibited the lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins and mRNA expressions in RAW 264.7 macrophages. Additionally, compound 1 reduced the mRNA levels of inflammatory cytokines. Taken together, the results of this study demonstrated that the new tanzawaic acid derivative inhibits LPS-induced inflammation. This is the first report on the anti-inflammatory activity of tanzawaic acid Q (1). PMID:26761016

  2. Design, synthesis, and characterization of a protein sequencing reagent yielding amino acid derivatives with enhanced detectability by mass spectrometry.

    PubMed Central

    Aebersold, R.; Bures, E. J.; Namchuk, M.; Goghari, M. H.; Shushan, B.; Covey, T. C.

    1992-01-01

    We report the design, chemical synthesis, and structural and functional characterization of a novel reagent for protein sequence analysis by the Edman degradation, yielding amino acid derivatives rapidly detectable at high sensitivity by ion-evaporation mass spectrometry. We demonstrate that the reagent 3-[4'(ethylene-N,N,N-trimethylamino)phenyl]-2-isothiocyanate is chemically stable and shows coupling and cyclization/cleavage yields comparable to phenylisothiocyanate, the standard reagent in chemical sequence analysis, under conditions typically encountered in manual or automated sequence analysis. Amino acid derivatives generated with this reagent were detectable by ion-evaporation mass spectrometry at the subfemtomole sensitivity level at a pace of one sample per minute. Furthermore, derivatives were identified by their mass, thus permitting the rapid and highly sensitive determination of the molecular nature of modified amino acids. Derivatives of amino acids with acidic, basic, polar, or hydrophobic side chains were reproducibly detectable at comparable sensitivities. The polar nature of the reagent required covalent immobilization of polypeptides prior to automated sequence analysis. This reagent, used in automated sequence analysis, has the potential for overcoming the limitations in sensitivity, speed, and the ability to characterize modified amino acid residues inherent in the chemical sequencing methods that are currently used. PMID:1304351

  3. Graphene-sensitized microporous membrane/solvent microextraction for the preconcentration of cinnamic acid derivatives in Rhizoma Typhonii.

    PubMed

    Xing, Rongrong; Hu, Shuang; Chen, Xuan; Bai, Xiaohong

    2014-09-01

    A novel graphene-sensitized microporous membrane/solvent microextraction method named microporous membrane/graphene/solvent synergistic microextraction, coupled with high-performance liquid chromatography and UV detection, was developed and introduced for the extraction and determination of three cinnamic acid derivatives in Rhizoma Typhonii. Several factors affecting performance were investigated and optimized, including the types of graphene and extraction solvent, concentration of graphene dispersed in octanol, sample phase pH, ionic strength, stirring rate, extraction time, extraction temperature, and sample volume. Under optimized conditions, the enrichment factors of cinnamic acid derivatives ranged from 75 to 269. Good linearities were obtained from 0.01 to 10 μg/mL for all analytes with regression coefficients between 0.9927 and 0.9994. The limits of quantification were <1 ng/mL, and satisfactory recoveries (99-104%) and precision (1.1-10.8%) were also achieved. The synergistic microextraction mechanism based on graphene sensitization was analyzed and described. The experimental results showed that the method was simple, sensitive, practical, and effective for the preconcentration and determination of cinnamic acid derivatives in Rhizoma Typhonii.

  4. Betulinic acid derived hydroxamates and betulin derived carbamates are interesting scaffolds for the synthesis of novel cytotoxic compounds.

    PubMed

    Wiemann, Jana; Heller, Lucie; Perl, Vincent; Kluge, Ralph; Ströhl, Dieter; Csuk, René

    2015-12-01

    The betulinic acid-derived hydroxamates 5-18, the amides 19-24, and betulin-derived bis-carbamates 25-28 as well as the carbamates 31-40 and 44-48 were prepared and evaluated for their antiproliferative activity in a photometric sulforhodamine B (SRB) assay against several human cancer cell lines and nonmalignant mouse fibroblasts (NIH 3T3). While for 3-O-acetyl hydroxamic acid 5 EC50 values as low as EC50 = 1.3 μM were found, N,O-bis-alkyl substituted hydroxamates showed lowered cytotoxicity (EC50 = 16-20 μM). In general, hydroxamic acid derivatives showed only reduced selectivity for tumor cells, except for allyl substituted compound 13 (EC50 = 5.9 μM for A2780 human ovarian carcinoma cells and EC50 > 30 μM for nonmalignant mouse fibroblasts). The cytotoxicity of betulinic acid derived amides 19-24 and of betulin derived bis-carbamates 25-28 was low, except for N-ethyl substituted 25. Hexyl substituted 39 showed EC50 = 5.6 μM (518A2 cells) while for mouse fibroblasts EC50 > 30 was determined.

  5. Arachidonic Acid Derivatives and Their Role in Peripheral Nerve Degeneration and Regeneration

    PubMed Central

    Camara-Lemarroy, Carlos Rodrigo; Gonzalez-Moreno, Emmanuel Irineo; Guzman-de la Garza, Francisco Javier; Fernandez-Garza, Nancy Esthela

    2012-01-01

    After peripheral nerve injury, a process of axonal degradation, debris clearance, and subsequent regeneration is initiated by complex local signaling, called Wallerian degeneration (WD). This process is in part mediated by neuroglia as well as infiltrating inflammatory cells and regulated by inflammatory mediators such as cytokines, chemokines, and the activation of transcription factors also related to the inflammatory response. Part of this neuroimmune signaling is mediated by the innate immune system, including arachidonic acid (AA) derivatives such as prostaglandins and leukotrienes. The enzymes responsible for their production, cyclooxygenases and lipooxygenases, also participate in nerve degeneration and regeneration. The interactions between signals for nerve regeneration and neuroinflammation go all the way down to the molecular level. In this paper, we discuss the role that AA derivatives might play during WD and nerve regeneration, and the therapeutic possibilities that arise. PMID:22997489

  6. The iA{beta}5p {beta}-breaker peptide regulates the A{beta}(25-35) interaction with lipid bilayers through a cholesterol-mediated mechanism

    SciTech Connect

    Vitiello, Giuseppe; Grimaldi, Manuela; D'Ursi, Anna Maria; D'Errico, Gerardino

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer iA{beta}5p shows a significant tendency to deeply penetrates the hydrophobic core of lipid membrane. Black-Right-Pointing-Pointer A{beta}(25-35) locates in the external region of the membrane causing a re-positioning of CHOL. Black-Right-Pointing-Pointer iA{beta}5p withholds cholesterol in the inner hydrophobic core of the lipid membrane. Black-Right-Pointing-Pointer iA{beta}5p prevents the A{beta}(25-35) release from the lipid membrane. -- Abstract: Alzheimer's disease is characterized by the deposition of aggregates of the {beta}-amyloid peptide (A{beta}) in the brain. A potential therapeutic strategy for Alzheimer's disease is the use of synthetic {beta}-sheet breaker peptides, which are capable of binding A{beta} but unable to become part of a {beta}-sheet structure, thus inhibiting the peptide aggregation. Many studies suggest that membranes play a key role in the A{beta} aggregation; consequently, it is strategic to investigate the interplay between {beta}-sheet breaker peptides and A{beta} in the presence of lipid bilayers. In this work, we focused on the effect of the {beta}-sheet breaker peptide acetyl-LPFFD-amide, iA{beta}5p, on the interaction of the A{beta}(25-35) fragment with lipid membranes, studied by Electron Spin Resonance spectroscopy, using spin-labeled membrane components (either phospholipids or cholesterol). The ESR results show that iA{beta}5p influences the A{beta}(25-35) interaction with the bilayer through a cholesterol-mediated mechanism: iA{beta}5p withholds cholesterol in the inner hydrophobic core of the bilayer, making the interfacial region more fluid and capable to accommodate A{beta}(25-35). As a consequence, iA{beta}5p prevents the A{beta}(25-35) release from the lipid membrane, which is the first step of the {beta}-amyloid aggregation process.

  7. Fenretinide mediated retinoic acid receptor signalling and inhibition of ceramide biosynthesis regulates adipogenesis, lipid accumulation, mitochondrial function and nutrient stress signalling in adipocytes and adipose tissue

    PubMed Central

    Mcilroy, George D.; Tammireddy, Seshu R.; Maskrey, Benjamin H.; Grant, Louise; Doherty, Mary K.; Watson, David G.; Delibegović, Mirela; Whitfield, Phillip D.; Mody, Nimesh

    2016-01-01

    Fenretinide (FEN) is a synthetic retinoid that inhibits obesity and insulin resistance in high-fat diet (HFD)-fed mice and completely prevents 3T3-L1 pre-adipocyte differentiation. The aim of this study was to determine the mechanism(s) of FEN action in 3T3-L1 adipocytes and in mice. We used the 3T3-L1 model of adipogenesis, fully differentiated 3T3-L1 adipocytes and adipose tissue from HFD-induced obese mice to investigate the mechanisms of FEN action. We measured expression of adipogenic and retinoid genes by qPCR and activation of nutrient-signalling pathways by western blotting. Global lipid and metabolite analysis was performed and specific ceramide lipid species measured by liquid chromatography-mass spectrometry. We provide direct evidence that FEN inhibits 3T3-L1 adipogenesis via RA-receptor (RAR)-dependent signaling. However, RARα antagonism did not prevent FEN-induced decreases in lipid levels in mature 3T3-L1 adipocytes, suggesting an RAR-independent mechanism. Lipidomics analysis revealed that FEN increased dihydroceramide lipid species 5- to 16-fold in adipocytes, indicating an inhibition of the final step of ceramide biosynthesis. A similar blockade in adipose tissue from FEN-treated obese mice was associated with a complete normalisation of impaired mitochondrial β-oxidation and tricarboxylic acid cycle flux. The FEN catabolite, 4-oxo-N-(4-hydroxyphenyl)retinamide (4-OXO), also decreased lipid accumulation without affecting adipogenesis. FEN and 4-OXO (but not RA) treatment additionally led to the activation of p38-MAPK, peIF2α and autophagy markers in adipocytes. Overall our data reveals FEN utilises both RAR-dependent and -independent pathways to regulate adipocyte biology, both of which may be required for FEN to prevent obesity and insulin resistance in vivo. PMID:26592777

  8. Mitotane Inhibits Sterol-O-Acyl Transferase 1 Triggering Lipid-Mediated Endoplasmic Reticulum Stress and Apoptosis in Adrenocortical Carcinoma Cells.

    PubMed

    Sbiera, Silviu; Leich, Ellen; Liebisch, Gerhard; Sbiera, Iuliu; Schirbel, Andreas; Wiemer, Laura; Matysik, Silke; Eckhardt, Carolin; Gardill, Felix; Gehl, Annemarie; Kendl, Sabine; Weigand, Isabel; Bala, Margarita; Ronchi, Cristina L; Deutschbein, Timo; Schmitz, Gerd; Rosenwald, Andreas; Allolio, Bruno; Fassnacht, Martin; Kroiss, Matthias

    2015-11-01

    Adrenocortical carcinoma (ACC) is a rare malignancy that harbors a dismal prognosis in advanced stages. Mitotane is approved as an orphan drug for treatment of ACC and counteracts tumor growth and steroid hormone production. Despite serious adverse effects, mitotane has been clinically used for decades. Elucidation of its unknown molecular mechanism of action seems essential to develop better ACC therapies. Here, we set out to identify the molecular target of mitotane and altered downstream mechanisms by combining expression genomics and mass spectrometry technology in the NCI-H295 ACC model cell line. Pathway analyses of expression genomics data demonstrated activation of endoplasmic reticulum (ER) stress and profound alteration of lipid-related genes caused by mitotane treatment. ER stress marker CHOP was strongly induced and the two upstream ER stress signalling events XBP1-mRNA splicing and eukaryotic initiation factor 2 A (eIF2α) phosphorylation were activated by mitotane in NCI-H295 cells but to a much lesser extent in four nonsteroidogenic cell lines. Lipid mass spectrometry revealed mitotane-induced increase of free cholesterol, oxysterols, and fatty acids specifically in NCI-H295 cells as cause of ER stress. We demonstrate that mitotane is an inhibitor of sterol-O-acyl-transferase 1 (SOAT1) leading to accumulation of these toxic lipids. In ACC tissue samples we show variable SOAT1 expression correlating with the response to mitotane treatment. In conclusion, mitotane confers adrenal-specific cytotoxicity and down-regulates steroidogenesis by inhibition of SOAT1 leading to lipid-induced ER stress. Targeting of cancer-specific lipid metabolism opens new avenues for treatment of ACC and potentially other types of cancer.

  9. The hepatitis C virus core protein inhibits adipose triglyceride lipase (ATGL)-mediated lipid mobilization and enhances the ATGL interaction with comparative gene identification 58 (CGI-58) and lipid droplets.

    PubMed

    Camus, Gregory; Schweiger, Martina; Herker, Eva; Harris, Charles; Kondratowicz, Andrew S; Tsou, Chia-Lin; Farese, Robert V; Herath, Kithsiri; Previs, Stephen F; Roddy, Thomas P; Pinto, Shirly; Zechner, Rudolf; Ott, Melanie

    2014-12-26

    Liver steatosis is a common health problem associated with hepatitis C virus (HCV) and an important risk factor for the development of liver fibrosis and cancer. Steatosis is caused by triglycerides (TG) accumulating in lipid droplets (LDs), cellular organelles composed of neutral lipids surrounded by a monolayer of phospholipids. The HCV nucleocapsid core localizes to the surface of LDs and induces steatosis in cultured cells and mouse livers by decreasing intracellular TG degradation (lipolysis). Here we report that core at the surface of LDs interferes with the activity of adipose triglyceride lipase (ATGL), the key lipolytic enzyme in the first step of TG breakdown. Expressing core in livers or mouse embryonic fibroblasts of ATGL(-/-) mice no longer decreases TG degradation as observed in LDs from wild-type mice, supporting the model that core reduces lipolysis by engaging ATGL. Core must localize at LDs to inhibit lipolysis, as ex vivo TG hydrolysis is impaired in purified LDs coated with core but not when free core is added to LDs. Coimmunoprecipitation experiments revealed that core does not directly interact with the ATGL complex but, unexpectedly, increased the interaction between ATGL and its activator CGI-58 as well as the recruitment of both proteins to LDs. These data link the anti-lipolytic activity of the HCV core protein with altered ATGL binding to CGI-58 and the enhanced association of both proteins with LDs.

  10. Novel 1,3-diacylamidopropane-2-[bis-(2-dimethylaminoethane)] carbamate pH-sensitive lipids for cationic liposome-mediated transfection

    NASA Astrophysics Data System (ADS)

    Spelios, Michael G.

    A novel series of 1,3-diacylamidopropane-2-[bis(2-dimethylaminoethane)] carbamate analogs (1,3lb) were designed for cationic lipid-assisted transfection (lipofection). First, their physicochemical properties in self-assemblies with and without plasmid DNA (pDNA) were evaluated to examine the effects of hydrophobic tail length and degree of saturation on gene delivery and expression. Significant in vitro lipofection was induced at a nitrogen:phosphate ratio (N:P) of 4:1 by the dimyristoyl, dipalmitoyl, and dioleoyl analogs 1,3lb2, 1,3lb3, and 1,3lb5, respectively, without inclusion of neutral "lipofection enhancing" co-lipids in the cationic lipid formulations. Lipofection was reduced in the presence of co-lipids except for 1,3lb5 which maintained reporter gene expression levels at N:P 4:1 and yielded increased bioactivity at a lower NP of 2:1. Physicochemical characterization of the bioactive transfection agents (cytofectins) revealed: high hydration and in-plane elasticity of lipid monolayers by Langmuir film balance measurements; fluid lipid bilayers, with gel---liquid crystalline phase transitions below physiological temperature, by fluorescence anisotropy; lipid mixing with biomembrane-mimicking vesicles by fluorescence resonance energy transfer; efficient pDNA binding and compaction by ethidium bromide displacement; cationic liposome---nucleic acid complexes (lipoplexes) with large particle sizes (mean diameter ≥ 500 nm) and zeta potentials of positive values by dynamic light scattering and electrophoretic mobility, respectively. The results suggest that well hydrated and elastic cationic lipids forming fluid lamellar assemblies are extremely potent and minimally toxic cytofectins. Second, a comparison was made between 1,3lb2 and two derivatives, one an isomer with a shorter space between the myristoyl chains and the other the monovalent form, in an effort to delineate the biological effects of interchain distance and pH-induced polar headgroup expandability

  11. D77, one benzoic acid derivative, functions as a novel anti-HIV-1 inhibitor targeting the interaction between integrase and cellular LEDGF/p75

    SciTech Connect

    Du Li; Zhao Yaxue; Chen, Jing; Yang Liumeng; Zheng Yongtang; Tang Yun Shen Xu Jiang Hualiang

    2008-10-10

    Integration of viral-DNA into host chromosome mediated by the viral protein HIV-1 integrase (IN) is an essential step in the HIV-1 life cycle. In this process, Lens epithelium-derived growth factor (LEDGF/p75) is discovered to function as a cellular co-factor for integration. Since LEDGF/p75 plays an important role in HIV integration, disruption of the LEDGF/p75 interaction with IN has provided a special interest for anti-HIV agent discovery. In this work, we reported that a benzoic acid derivative, 4-[(5-bromo-4-{l_brace}[2,4-dioxo-3-(2-oxo-2-phenylethyl) -1,3-thiazolidin-5-ylidene]methyl{r_brace}-2-ethoxyphenoxy)methyl]benzoic acid (D77) could potently inhibit the IN-LEDGF/p75 interaction and affect the HIV-1 IN nuclear distribution thus exhibiting antiretroviral activity. Molecular docking with site-directed mutagenesis analysis and surface plasmon resonance (SPR) binding assays has clarified possible binding mode of D77 against HIV-1 integrase. As the firstly discovered small molecular compound targeting HIV-1 integrase interaction with LEDGF/p75, D77 might supply useful structural information for further anti-HIV agent discovery.

  12. Lipids and immune function.

    PubMed

    Vitale, J J; Broitman, S A

    1981-09-01

    There is in vitro and in vivo evidence to suggest that dietary lipids play a role in modulating immune function. A review of the current literature on the interrelationships among dietary lipids, blood cholesterol levels, immunosuppression, and tumorigenesis makes for a very strong argument that (a) immunosuppression may be causally related to lymphoproliferative disorders, as well as to tumorigenesis and (b) diets high in polyunsaturated fat, relative to diets high in saturated fat, are more immunosuppressive and are better promotors of tumorigenesis. The effects of dietary fat on immune function seem to be mediated though its component parts, the unsaturated fatty acids, specially linoleic, linolenic, and arachidonic. It is not clear how these components affect immune function. Several studies suggest that one effect is mediated by altering the lipid component of the cell membrane and thus its fluidity; the more fluid the membrane, the less responsive it is. Thus, fluidity of both immune cells and those to be destroyed or protected may be affected. The effects of saturated as well as unsaturated fatty acids may be mediated by modulating serum lipoprotein levels, prostaglandin metabolism, and cholesterol concentrations and metabolism.

  13. The process of lipid storage in insect oocytes: The involvement of β-chain of ATP synthase in lipophorin-mediated lipid transfer in the chagas' disease vector Panstrongylus megistus (Hemiptera: Reduviidae).

    PubMed

    Fruttero, Leonardo L; Leyria, Jimena; Ramos, Fabián O; Stariolo, Raúl; Settembrini, Beatriz P; Canavoso, Lilián E

    2017-01-01

    Lipophorin is the main lipoprotein in the hemolymph of insects. During vitellogenesis, lipophorin delivers its hydrophobic cargo to developing oocytes by its binding to non-endocytic receptors at the plasma membrane of the cells. In some species however, lipophorin may also be internalized to some extent, thus maximizing the storage of lipid resources in growing oocytes. The ectopic β chain of ATP synthase (β-ATPase) was recently described as a putative non-endocytic lipophorin receptor in the anterior midgut of the hematophagous insect Panstrongylus megistus. In the present work, females of this species at the vitellogenic stage of the reproductive cycle were employed to investigate the role of β-ATPase in the transfer of lipids to the ovarian tissue. Subcellular fractionation and western blot revealed the presence of β-ATPase in the microsomal membranes of the ovarian tissue, suggesting its localization in the plasma membrane. Immunofluorescence assays showed partial co-localization of β-ATPase and lipophorin in the membrane of oocytes as well as in the basal domain of the follicular epithelial cells. Ligand blotting and co-immunoprecipitation approaches confirmed the interaction between lipophorin and β-ATPase. In vivo experiments with an anti-β-ATPase antibody injected to block such an interaction demonstrated that the antibody significantly impaired the transfer of fatty acids from lipophorin to the oocyte. However, the endocytic pathway of lipophorin was not affected. On the other hand, partial inhibition of ATP synthase activity did not modify the transfer of lipids from lipophorin to oocytes. When the assays were performed at 4°C to diminish endocytosis, the results showed that the antibody interfered with lipophorin binding to the oocyte plasma membrane as well as with the transfer of fatty acids from the lipoprotein to the oocyte. The findings strongly support that β-ATPase plays a role as a docking lipophorin receptor at the ovary of P. megistus

  14. Lipid-induced insulin resistance mediated by the proinflammatory receptor TLR4 requires saturated fatty acid-induced ceramide biosynthesis in mice.

    PubMed

    Holland, William L; Bikman, Benjamin T; Wang, Li-Ping; Yuguang, Guan; Sargent, Katherine M; Bulchand, Sarada; Knotts, Trina A; Shui, Guanghou; Clegg, Deborah J; Wenk, Markus R; Pagliassotti, Michael J; Scherer, Philipp E; Summers, Scott A

    2011-05-01

    Obesity is associated with an enhanced inflammatory response that exacerbates insulin resistance and contributes to diabetes, atherosclerosis, and cardiovascular disease. One mechanism accounting for the increased inflammation associated with obesity is activation of the innate immune signaling pathway triggered by TLR4 recognition of saturated fatty acids, an event that is essential for lipid-induced insulin resistance. Using in vitro and in vivo systems to model lipid induction of TLR4-dependent inflammatory events in rodents, we show here that TLR4 is an upstream signaling component required for saturated fatty acid-induced ceramide biosynthesis. This increase in ceramide production was associated with the upregulation of genes driving ceramide biosynthesis, an event dependent of the activity of the proinflammatory kinase IKKβ. Importantly, increased ceramide production was not required for TLR4-dependent induction of inflammatory cytokines, but it was essential for TLR4-dependent insulin resistance. These findings suggest that sphingolipids such as ceramide might be key components of the signaling networks that link lipid-induced inflammatory pathways to the antagonism of insulin action that contributes to diabetes.

  15. Lipid-induced insulin resistance mediated by the proinflammatory receptor TLR4 requires saturated fatty acid–induced ceramide biosynthesis in mice

    PubMed Central

    Holland, William L.; Bikman, Benjamin T.; Wang, Li-Ping; Yuguang, Guan; Sargent, Katherine M.; Bulchand, Sarada; Knotts, Trina A.; Shui, Guanghou; Clegg, Deborah J.; Wenk, Markus R.; Pagliassotti, Michael J.; Scherer, Philipp E.; Summers, Scott A.

    2011-01-01

    Obesity is associated with an enhanced inflammatory response that exacerbates insulin resistance and contributes to diabetes, atherosclerosis, and cardiovascular disease. One mechanism accounting for the increased inflammation associated with obesity is activation of the innate immune signaling pathway triggered by TLR4 recognition of saturated fatty acids, an event that is essential for lipid-induced insulin resistance. Using in vitro and in vivo systems to model lipid induction of TLR4-dependent inflammatory events in rodents, we show here that TLR4 is an upstream signaling component required for saturated fatty acid–induced ceramide biosynthesis. This increase in ceramide production was associated with the upregulation of genes driving ceramide biosynthesis, an event dependent of the activity of the proinflammatory kinase IKKβ. Importantly, increased ceramide production was not required for TLR4-dependent induction of inflammatory cytokines, but it was essential for TLR4-dependent insulin resistance. These findings suggest that sphingolipids such as ceramide might be key components of the signaling networks that link lipid-induced inflammatory pathways to the antagonism of insulin action that contributes to diabetes. PMID:21490391

  16. HIF-1 is induced via EGFR activation and mediates resistance to anoikis-like cell death under lipid rafts/caveolae-disrupting stress.

    PubMed

    Lee, Seong-Hee; Koo, Kyung Hee; Park, Jong-Wan; Kim, Hee-Jung; Ye, Sang-Kyu; Park, Jong Bae; Park, Byung-Kiu; Kim, Yong-Nyun

    2009-12-01

    The plasma membrane microdomains, lipid rafts, are involved in regulation of cellular functions such as cell survival and adhesion. Cholesterol is a critical component of lipid rafts in terms of their integrity and functions and rafts disruption by cholesterol depletion can induce detachment-induced cell death. Hypoxia inducible factor-1 (HIF-1) alpha is stabilized in hypoxia and transactivates numerous genes required for cellular adaptation to hypoxia. It is also induced by non-hypoxic stimuli and contributes to cell survival. Because hypoxia inhibits cholesterol synthesis and HIF-1alpha plays a role in this process, we here explored a possible connection between lipid rafts and HIF-1alpha. We investigated whether HIF-1alpha is regulated during cholesterol depletion/rafts disruption in A431 cells in normoxic conditions. Methyl-beta cyclodextrin (MbetaCD), which induces cholesterol depletion, upregulated HIF-1alpha even under normoxic conditions and this upregulation required epidermal growth factor receptor (EGFR) and extracellular signal-regulated kinase 1 and 2 activation, but not Akt activation. MbetaCD treatment induced HIF-1alpha upregulation at both the transcriptional and translational levels but not at the posttranslational levels. In addition, MbetaCD robustly induced vascular endothelial growth factor production and stimulated an hypoxia response element-driven luciferase reporter activity under normoxic conditions, indicating that MbetaCD-induced HIF-1alpha is functionally activated. Both EGFR activity and HIF-1alpha expression were higher in the attached cells than in the detached cells after MbetaCD treatment. Furthermore, inhibition of HIF-1alpha by RNA interference accelerated cell detachment, thus increasing cell death, indicating that HIF-1alpha expression attenuates MbetaCD-induced anoikis-like cell death. These data suggest that, depending on cholesterol levels, lipid rafts or membrane fluidity are probably to regulate HIF-1alpha expression in

  17. Hypoxia-inducible factor 1 mediates hypoxia-induced cardiomyocyte lipid accumulation by reducing the DNA binding activity of peroxisome proliferator-activated receptor {alpha}/retinoid X receptor

    SciTech Connect

    Belanger, Adam J.; Luo Zhengyu; Vincent, Karen A.; Akita, Geoffrey Y.; Cheng, Seng H.; Gregory, Richard J.; Jiang Canwen

    2007-12-21

    In response to cellular hypoxia, cardiomyocytes adapt to consume less oxygen by shifting ATP production from mitochondrial fatty acid {beta}-oxidation to glycolysis. The transcriptional activation of glucose transporters and glycolytic enzymes by hypoxia is mediated by hypoxia-inducible factor 1 (HIF-1). In this study, we examined whether HIF-1 was involved in the suppression of mitochondrial fatty acid {beta}-oxidation in hypoxic cardiomyocytes. We showed that either hypoxia or adenovirus-mediated expression of a constitutively stable hybrid form (HIF-1{alpha}/VP16) suppressed mitochondrial fatty acid metabolism, as indicated by an accumulation of intracellular neutral lipid. Both treatments also reduced the mRNA levels of muscle carnitine palmitoyltransferase I which catalyzes the rate-limiting step in the mitochondrial import of fatty acids for {beta}-oxidation. Furthermore, adenovirus-mediated expression of HIF-1{alpha}/VP16 in cardiomyocytes under normoxic conditions also mimicked the reduction in the DNA binding activity of peroxisome proliferator-activated receptor {alpha} (PPAR{alpha})/retinoid X receptor (RXR), in the presence or absence of a PPAR{alpha} ligand. These results suggest that HIF-1 may be involved in hypoxia-induced suppression of fatty acid metabolism in cardiomyocytes by reducing the DNA binding activity of PPAR{alpha}/RXR.

  18. The pmrCAB operon mediates polymyxin resistance in Acinetobacter baumannii ATCC 17978 and clinical isolates through phosphoethanolamine modification of lipid A.

    PubMed

    Arroyo, Luis A; Herrera, Carmen M; Fernandez, Lucia; Hankins, Jessica V; Trent, M Stephen; Hancock, Robert E W

    2011-08-01

    The emergence of multidrug resistance among Acinetobacter baumannii is leading to an increasing dependence on the use of polymyxins as last-hope antibiotics. Here, we utilized genetic and biochemical methods to define the involvement of the pmrCAB operon in polymyxin resistance in this organism. Sequence analysis of 16 polymyxin B-resistant strains, including 6 spontaneous mutants derived from strain ATCC 17978 and 10 clinical isolates from diverse sources, revealed that they had independent mutations in the pmrB gene, encoding a sensor kinase, or in the response regulator PmrA. Knockout of the pmrB gene in two mutants and two clinical isolates led to a decrease in the polymyxin B susceptibility of these strains, which could be restored with the cloned pmrAB genes from the mutants but not from the wild type. Reverse transcription-quantitative PCR (RT-qPCR) analysis also showed a correlation between the expression of pmrC and polymyxin B resistance. Characterization of lipid A species from the mutant strains, by thin-layer chromatography and mass spectrometry, indicated that the addition of phosphoethanolamine to lipid A correlated with resistance. This addition is performed in Salmonella enterica serovar Typhimurium by the product of the pmrC gene, which is a homolog of the pmrC gene from Acinetobacter. Knockout of this gene in the mutant R2 [pmrB(T235I)] reversed resistance as well as phosphoethanolamine modification of lipid A. These results demonstrate that specific alterations in the sequence of the pmrCAB operon are responsible for resistance to polymyxins in A. baumannii.

  19. The pmrCAB Operon Mediates Polymyxin Resistance in Acinetobacter baumannii ATCC 17978 and Clinical Isolates through Phosphoethanolamine Modification of Lipid A▿

    PubMed Central

    Arroyo, Luis A.; Herrera, Carmen M.; Fernandez, Lucia; Hankins, Jessica V.; Trent, M. Stephen; Hancock, Robert E. W.

    2011-01-01

    The emergence of multidrug resistance among Acinetobacter baumannii is leading to an increasing dependence on the use of polymyxins as last-hope antibiotics. Here, we utilized genetic and biochemical methods to define the involvement of the pmrCAB operon in polymyxin resistance in this organism. Sequence analysis of 16 polymyxin B-resistant strains, including 6 spontaneous mutants derived from strain ATCC 17978 and 10 clinical isolates from diverse sources, revealed that they had independent mutations in the pmrB gene, encoding a sensor kinase, or in the response regulator PmrA. Knockout of the pmrB gene in two mutants and two clinical isolates led to a decrease in the polymyxin B susceptibility of these strains, which could be restored with the cloned pmrAB genes from the mutants but not from the wild type. Reverse transcription-quantitative PCR (RT-qPCR) analysis also showed a correlation between the expression of pmrC and polymyxin B resistance. Characterization of lipid A species from the mutant strains, by thin-layer chromatography and mass spectrometry, indicated that the addition of phosphoethanolamine to lipid A correlated with resistance. This addition is performed in Salmonella enterica serovar Typhimurium by the product of the pmrC gene, which is a homolog of the pmrC gene from Acinetobacter. Knockout of this gene in the mutant R2 [pmrB(T235I)] reversed resistance as well as phosphoethanolamine modification of lipid A. These results demonstrate that specific alterations in the sequence of the pmrCAB operon are responsible for resistance to polymyxins in A. baumannii. PMID:21646482

  20. Efficient Cellular Knockdown Mediated by siRNA Nanovectors of Gemini Cationic Lipids Having Delocalizable Headgroups and Oligo-Oxyethylene Spacers.

    PubMed

    Martínez-Negro, María; Kumar, Krishan; Barrán-Berdón, Ana L; Datta, Sougata; Kondaiah, Paturu; Junquera, Elena; Bhattacharya, Santanu; Aicart, Emilio

    2016-08-31

    The use of small interfering RNAs (siRNAs) to silence specific genes is one of the most promising approaches in gene therapy, but it requires efficient nanovectors for successful cellular delivery. Recently, we reported liposomal gene carriers derived from a gemini cationic lipid (GCL) of the 1,2-bis(hexadecyl dimethyl imidazolium) oligo-oxyethylene series ((C16Im)2(C2H4O)nC2H4 with n = 1, 2, or 3) and 1,2-dioleyol phosphatidylethanolamine as highly efficient cytofectins for pDNA. On the basis of the satisfactory outcomes of the previous study, the present work focuses on the utility of coliposomes of these gemini lipids with the biocompatible neutral lipid mono oleoyl glycerol (MOG) as highly potent vectors for siRNA cellular transport in the presence of serum. The (C16Im)2(C2H4O)nC2H4/MOG-siRNA lipoplexes were characterized through (i) a physicochemical study (zeta potential, cryo-transmission electron microscopy, small-angle X-ray scattering, and fluorescence anisotropy) to establish the relationship between size, structure, fluidity, and the interaction between siRNA and the GCL/MOG gene vectors and (ii) a biological analysis (flow cytometry, fluorescence microscopy, and cell viability) to report the anti-GFP siRNA transfections in HEK 293T, HeLa, and H1299 cancer cell lines. The in vitro biological analysis confirms the cellular uptake and indicates that a short spacer, a very low molar fraction of GCL in the mixed lipid, and a moderate effective charge ratio of the lipoplex yielded maximum silencing efficacy. At these experimental conditions, the siRNA used in this work is compacted by the GCL/MOG nanovectors by forming two cubic structures (Ia3d and Pm3n) that are correlated with excellent silencing activity. These liposomal nanocarriers possess high silencing activity with a negligible cytotoxicity, which strongly supports their practical use for in vivo knockdown studies.

  1. Effects of a New Glutamic Acid Derivative on Myocardial Contractility of Stressed Animals under Conditions of Nitric Oxide Synthesis Blockade.

    PubMed

    Tyurenkov, I N; Perfilova, V N; Sadikova, N V; Berestovitskaya, V M; Vasil'eva, O S

    2015-07-01

    Glufimet (glutamic acid derivative) in a dose of 28.7 mg/kg limited the reduction of the cardiac functional reserve in animals subjected to 24-h stress under conditions of nonselective NO synthase blockade with L-NAME (10 mg/kg). Adrenoreactivity and increased afterload tests showed that the increment of myocardial contraction/relaxation rates, left-ventricular pressure, and HR were significantly higher in glufimet-treated stressed animals with NO synthesis blockade than in animals which received no glufimet. The efficiency of glufimet was higher than that of phenibut (the reference drug).

  2. Synthetic amphibian peptides and short amino-acids derivatives against planktonic cells and mature biofilm of Providencia stuartii clinical strains.

    PubMed

    Ostrowska, Kinga; Kamysz, Wojciech; Dawgul, Małgorzata; Różalski, Antoni

    2014-01-01

    Over the last decade, the growing number of multidrug resistant strains limits the use of many of the currently available chemotherapeutic agents. Furthermore, bacterial biofilm, due to its complex structure, constitutes an effective barrier to conventional antibiotics. The in vitro activities of naturally occurring peptide (Citropin 1.1), chemically engineered analogue (Pexiganan), newly-designed, short amino-acid derivatives (Pal-KK-NH2, Pal-KKK-NH2, Pal-RRR-NH2) and six clinically used antimicrobial agents (Gatifloxacin, Ampicilin, Cefotaxime, Ceftriaxone, Cefuroxime and Cefalexin) were investigated against planktonic cells and mature biofilm of multidrug-resistant Providencia stuartii strains, isolated from urological catheters. The MICs, MBCs values were determined by broth microdilution technique. Inhibition of biofilm formation by antimicrobial agents as well as biofilm susceptibility assay were tested using a surrogate model based on the Crystal Violet method. The antimicrobial activity of amino-acids derivatives and synthetic peptides was compared to that of clinically used antibiotics. For planktonic cells, MICs of peptides and antibiotics ranged between 1 and 256 μg/ml and 256 and ≥ 2048 μg/ml, respectively. The MBCs values of Pexiganan, Citropin 1.1 and amino-acids derivatives were between 16 and 256 μg/ml, 64 and 256 μg/ml and 16 and 512 μg/ml, respectively. For clinically used antibiotics the MBCs values were above 2048 μg/ml. All of the tested peptides and amino-acids derivatives, showed inhibitory activity against P. stuartii biofilm formation, in relation to their concentrations. Pexiganan and Citropin 1.1 in concentration range 32 and 256 μg/ml caused both strong and complete suppression of biofilm formation. None of the antibiotics caused complete inhibition of biofilm formation process. The biofilm susceptibility assay verified the extremely poor antibiofilm activity of conventional antibiotics compared to synthetic peptides. The

  3. [The establishment of the MPEL for carboxylic acid derivatives in the air of a work area by using mathematical models].

    PubMed

    Gurova, A I; Smoliar, N Ia; Drozhzhina, N A

    1992-01-01

    Reports of MACs for carboxylic acid derivatives as sodium methoxyacetate (SMOA), methyl chlorpropionate (MCP) and acetoacetic ether (AAE). SMOA shows low toxicity, no cumulation and specific action MCP demonstrates moderate toxicity, low cumulation no specific action in concentrations close to Limac. AAE presents toxicity low in oral usage and moderate when inhaled, low cumulation, no irritation and sensitization. Tentative safe level of injury and MAC estimated for the aforesaid substances together with toxicity parameters compared with the substances studied before allowed the authors to set the MAC of SMOA--10, MCP--2, AAE--10 mg/m3.

  4. Enantioseparation of gantofiban precursors on chiral stationary phases of the poly-(N-acryloyl amino acid derivative)-type.

    PubMed

    Schulte, Michael; Devant, R; Grosser, R

    2002-01-15

    A separation strategy for the preparative enantioseparation of intermediates of the synthesis route towards the new antithrombotic drug Gantofiban is outlined. The selectivities of six different intermediates on a series of chiral stationary phases of the poly-[N-(meth-)acryloyl amino acid derivative]-type are determined. The separations are optimized with respect to high enantioselectivities and good solubilities in the mobile phase. For three optimized combinations of chiral stationary and mobile phases the separation parameters for a simulated moving bed-systems are determined.

  5. Caffeoylglycolic and caffeoylamino acid derivatives, halfmers of L-chicoric acid, as new HIV-1 integrase inhibitors.

    PubMed

    Lee, Seung Uk; Shin, Cha-Gyun; Lee, Chong-Kyo; Lee, Yong Sup

    2007-10-01

    Human immunodeficiency virus (HIV) integrase (IN) catalyzes the integration of HIV DNA copy into the host cell DNA. L-Chicoric acid (1) has been found to be one of the most potent HIV-1 integrase inhibitor. Caffeoylglycolic and caffeoylamino acid derivatives' halfmeric structures of L-chicoric acid 2 were synthesized for the purpose of simplifying the structure of L-chicoric acid. Among synthesized, compounds 2c and 3f showed HIV-1 IN inhibitory activities with IC(50) values of 10.5 and 12.0 microM, respectively, comparable to that of parent compound L-chicoric acid (IC(50)=15.7 microM).

  6. Basic quinolinonyl diketo acid derivatives as inhibitors of HIV integrase and their activity against RNase H function of reverse transcriptase.

    PubMed

    Costi, Roberta; Métifiot, Mathieu; Chung, Suhman; Cuzzucoli Crucitti, Giuliana; Maddali, Kasthuraiah; Pescatori, Luca; Messore, Antonella; Madia, Valentina Noemi; Pupo, Giovanni; Scipione, Luigi; Tortorella, Silvano; Di Leva, Francesco Saverio; Cosconati, Sandro; Marinelli, Luciana; Novellino, Ettore; Le Grice, Stuart F J; Corona, Angela; Pommier, Yves; Marchand, Christophe; Di Santo, Roberto

    2014-04-24

    A series of antiviral basic quinolinonyl diketo acid derivatives were developed as inhibitors of HIV-1 IN. Compounds 12d,f,i inhibited HIV-1 IN with IC50 values below 100 nM for strand transfer and showed a 2 order of magnitude selectivity over 3'-processing. These strand transfer selective inhibitors also inhibited HIV-1 RNase H with low micromolar potencies. Molecular modeling studies based on both the HIV-1 IN and RNase H catalytic core domains provided new structural insights for the future development of these compounds as dual HIV-1 IN and RNase H inhibitors.

  7. Inhibition of stromelysin-1 by caffeic acid derivatives from a propolis sample from Algeria.

    PubMed

    Segueni, Narimane; Magid, Abdulmagid Alabdul; Decarme, Martine; Rhouati, Salah; Lahouel, Mesbah; Antonicelli, Frank; Lavaud, Catherine; Hornebeck, William

    2011-07-01

    Stromelysin-1 (matrix metalloproteinase-3: MMP-3) occupies a central position in collagenolytic and elastolytic cascades, leading to cutaneous intrinsic and extrinsic aging. We screened extracts of a propolis sample from Algeria with the aim to isolate compounds able to selectively inhibit this enzyme. A butanolic extract (B (3)) of the investigated propolis sample was found to potently inhibit MMP-3 activity (IC (50) = 0.15 ± 0.03 µg/mL), with no or only weak activity on other MMPs. This fraction also inhibited plasmin amidolytic activity (IC (50) = 0.05 µg/mL) and impeded plasmin-mediated proMMP-3 activation. B (3) was fractionated by HPLC, and one compound, characterized by NMR and mass spectroscopy and not previously identified in propolis, i.e., (+)-chicoric acid, displayed potent IN VITRO MMP-3 inhibitory activity (IC (50) = 6.3 × 10 (-7) M). In addition, both caffeic acid and (+)-chicoric acid methyl ester present in fraction B (3) significantly inhibited UVA-mediated MMP-3 upregulation by fibroblasts.

  8. Substrate-selective Inhibition of Cyclooxygeanse-2 by Fenamic Acid Derivatives Is Dependent on Peroxide Tone.

    PubMed

    Orlando, Benjamin J; Malkowski, Michael G

    2016-07-15

    Cyclooxygenase-2 (COX-2) catalyzes the oxygenation of arachidonic acid (AA) and endocannabinoid substrates, placing the enzyme at a unique junction between the eicosanoid and endocannabinoid signaling pathways. COX-2 is a sequence homodimer, but the enzyme displays half-of-site reactivity, such that only one monomer of the dimer is active at a given time. Certain rapid reversible, competitive nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to inhibit COX-2 in a substrate-selective manner, with the binding of inhibitor to a single monomer sufficient to inhibit the oxygenation of endocannabinoids but not arachidonic acid. The underlying mechanism responsible for substrate-selective inhibition has remained elusive. We utilized structural and biophysical methods to evaluate flufenamic acid, meclofenamic acid, mefenamic acid, and tolfenamic acid for their ability to act as substrate-selective inhibitors. Crystal structures of each drug in complex with human COX-2 revealed that the inhibitor binds within the cyclooxygenase channel in an inverted orientation, with the carboxylate group interacting with Tyr-385 and Ser-530 at the top of the channel. Tryptophan fluorescence quenching, continuous-wave electron spin resonance, and UV-visible spectroscopy demonstrate that flufenamic acid, mefenamic acid, and tolfenamic acid are substrate-selective inhibitors that bind rapidly to COX-2, quench tyrosyl radicals, and reduce higher oxidation states of the heme moiety. Substrate-selective inhibition was attenuated by the addition of the lipid peroxide 15-hydroperoxyeicosatertaenoic acid. Collectively, these studies implicate peroxide tone as an important mechanistic component of substrate-selective inhibition by flufenamic acid, mefenamic acid, and tolfenamic acid.

  9. CoMFA and CoMSIA 3D-QSAR analysis on hydroxamic acid derivatives as urease inhibitors.

    PubMed

    Ul-Haq, Zaheer-; Wadood, Abdul; Uddin, Reaz

    2009-02-01

    Urease (EC 3.5.1.5) serves as a virulence factor in pathogens that are responsible for the development of many diseases in humans and animals. Urease allows soil microorganisms to use urea as a source of nitrogen and aid in the rapid break down of urea-based fertilizers resulting in phytopathicity. It has been well established that hydroxamic acids are the potent inhibitors of urease activity. The 3D-QSAR studies on thirty five hydroxamic acid derivatives as known urease inhibitors were performed by Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Indices Analysis (CoMSIA) methods to determine the factors required for the activity of these compounds. The CoMFA model produced statistically significant results with cross-validated (q(2)) 0.532 and conventional (r(2)) correlation coefficients 0.969.The model indicated that the steric field (70.0%) has greater influence on hydroxamic acid inhibitors than the electrostatic field (30.0%). Furthermore, five different fields: steric, electrostatic, hydrophobic, H-bond donor and H-bond acceptor assumed to generate the CoMSIA model, which gave q(2) 0.665 and r(2) 0.976.This model showed that steric (43.0%), electrostatic (26.4%) and hydrophobic (20.3%) properties played a major role in urease inhibition. The analysis of CoMFA and CoMSIA contour maps provided insight into the possible modification of the hydroxamic acid derivatives for improved activity.

  10. The Effects of Benzofuran-2-Carboxylic Acid Derivatives as Countermeasures in Immune Modulation and Cancer Cell Inhibition

    NASA Astrophysics Data System (ADS)

    Sundaresan, A.; Marriott, K.; Mao, J.; Bhuiyan, S.; Denkins, P.

    2015-06-01

    Microgravity and radiation exposure experienced during space flights result in immune system suppression. In long-term spaceflight, the crew is exposed to space radiation, microgravity, infectious agents from other crew members, and microbial contamination, all of which have a significant impact on the body's immune system and may contribute to the development of autoimmune diseases, allergic reactions, and/or cancer initiation. Many studies have revealed strong effects of microgravity on immune cell function, and microgravity is now considered as one of the major causes of immune dysfunction during space flight (Sundaresan, Int. J. Transp. Phenom. 12(1-2), 93-100, 2011; Martinelli et al., IEEE Eng. Biol. Med. 28(4), 85-90, 2009). We screened two newly synthetized derivatives of benzofuran 2-carboxylic acid, KMEG and KM12. The former KMEG was assessed for lymphoproliferative activities while the latter, KM12, was used in an array of cancer cell lines for testing its cancer inhibiting effects. For ground-based studies, synthetic benzofuran-2-carboxylic acid derivatives were assessed for biological effects in several scenarios, which involved exposure to modeled microgravity and radiation, as well as their immune enhancement and anti-cancer effects. Initial findings indicate that the benzofuran-2-carboxylic acid derivatives possibly have immune enhancing and anti-tumor properties in human lymphocytes and cancer cells exposed to analog spaceflight conditions modeled microgravity and γ-radiation).

  11. Synthesis and olfactory activity of unnatural, sulfated 5β-bile acid derivatives in the sea lamprey (Petromyzon marinus)

    PubMed Central

    Burns, Aaron C.; Sorensen, Peter W.

    2011-01-01

    A variety of unnatural bile acid derivatives (9a–9f) were synthesized and used to examine the specificity with which the sea lamprey (Petromyzon marinus) olfactory system detects these compounds. These compounds are analogs of petromyzonol sulfate (PS, 1), a component of the sea lamprey migratory pheromone. Both the stereochemical configuration at C5 (i.e., 5α vs. 5β) and the extent and sites of oxygenation (hydroxylation or ketonization) of the bile acid derived steroid skeleton were evaluated by screening the compounds for olfactory activity using electro-olfactogram recording. 5β-Petromyzonol sulfate (9a) elicited a considerable olfactory response at sub-nanomolar concentration. In addition, less oxygenated systems (i.e., 9b–9e) elicited olfactory responses, albeit with less potency. The sea lamprey sex pheromone mimic 9f (5β-3-ketopetromyzonol sulfate) was also examined and found to produce a much lower olfactory response. Mixture studies conducted with 9a and PS (1) suggest that stimulation is occurring via similar modes of activation, demonstrating a relative lack of specificity for recognition of the allo-configuration (i.e., 5α) in sea lamprey olfaction. This attribute could facilitate design of pheromone analogs to control this invasive species. PMID:21145335

  12. Facile C(sp(2))-C(sp(2)) bond cleavage in oxalic acid-derived radicals.

    PubMed

    Molt, Robert W; Lecher, Alison M; Clark, Timothy; Bartlett, Rodney J; Richards, Nigel G J

    2015-03-11

    Oxalate decarboxylase (OxDC) catalyzes the Mn-dependent conversion of the oxalate monoanion into CO2 and formate. Many questions remain about the catalytic mechanism of OxDC although it has been proposed that the reaction proceeds via substrate-based radical intermediates. Using coupled cluster theory combined with implicit solvation models we have examined the effects of radical formation on the structure and reactivity of oxalic acid-derived radicals in aqueous solution. Our results show that the calculated solution-phase free-energy barrier for C-C bond cleavage to form CO2 is decreased from 34.2 kcal/mol for oxalic acid to only 9.3 kcal/mol and a maximum of 3.5 kcal/mol for the cationic and neutral oxalic acid-derived radicals, respectively. These studies also show that the C-C σ bonding orbital of the radical cation contains only a single electron, giving rise to an elongated C-C bond distance of 1.7 Å; a similar lengthening of the C-C bond is not observed for the neutral radical. This study provides new chemical insights into the structure and stability of plausible intermediates in the catalytic mechanism of OxDC, and suggests that removal of an electron to form a radical (with or without the concomitant loss of a proton) may be a general strategy for cleaving the unreactive C-C bonds between adjacent sp(2)-hybridized carbon atoms.

  13. Value-added potential of expeller-pressed canola oil refining: characterization of sinapic acid derivatives and tocopherols from byproducts.

    PubMed

    Chen, Yougui; Thiyam-Hollander, Usha; Barthet, Veronique J; Aachary, Ayyappan A

    2014-10-08

    Valuable phenolic antioxidants are lost during oil refining, but evaluation of their occurrence in refining byproducts is lacking. Rapeseed and canola oil are both rich sources of sinapic acid derivatives and tocopherols. The retention and loss of sinapic acid derivatives and tocopherols in commercially produced expeller-pressed canola oils subjected to various refining steps and the respective byproducts were investigated. Loss of canolol (3) and tocopherols were observed during bleaching (84.9%) and deodorization (37.6%), respectively. Sinapic acid (2) (42.9 μg/g), sinapine (1) (199 μg/g), and canolol (344 μg/g) were found in the refining byproducts, namely, soap stock, spent bleaching clay, and wash water, for the first time. Tocopherols (3.75 mg/g) and other nonidentified phenolic compounds (2.7 mg sinapic acid equivalent/g) were found in deodistillates, a byproduct of deodorization. DPPH radical scavenging confirmed the antioxidant potential of the byproducts. This study confirms the value-added potential of byproducts of refining as sources of endogenous phenolics.

  14. Antineurodegenerative effect of phenolic extracts and caffeic acid derivatives in romaine lettuce on neuron-like PC-12 cells.

    PubMed

    Im, Sung-Eun; Yoon, Hyungeun; Nam, Tae-Gyu; Heo, Ho Jin; Lee, Chang Yong; Kim, Dae-Ok

    2010-08-01

    In recent decades, romaine lettuce has been one of the fastest growing vegetables with respect to its consumption and production. An understanding is needed of the effect of major phenolic phytochemicals from romaine lettuce on biological protection for neuron-like PC-12 cells. Phenolics in fresh romaine lettuce were extracted, and then its total phenolics and total antioxidant capacity were measured spectrophotometrically. Neuroprotective effects of phenolic extract of romaine lettuce and its pure caffeic acid derivatives (caffeic, chicoric, chlorogenic, and isochlorogenic acids) in PC-12 cells were evaluated using two different in vitro methods: lactate dehydrogenase release and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assays. Total phenolics and total antioxidant capacity of 100 g of fresh romaine lettuce averaged 22.7 mg of gallic acid equivalents and 31.0 mg of vitamin C equivalents, respectively. The phenolic extract of romaine lettuce protected PC-12 cells against oxidative stress caused by H(2)O(2) in a dose-dependent manner. Isochlorogenic acid, one of the phenolics in romaine lettuce, showed stronger neuroprotection than the other three caffeic acid derivatives also found in the lettuce. Although romaine lettuce had lower levels of phenolics and antioxidant capacity compared to other common vegetables, its contribution to total antioxidant capacity and antineurodegenerative effect in human diets would be higher because of higher amounts of its daily per capita consumption compared to other common vegetables.

  15. Quantification of amino acids in fermentation media by isocratic HPLC analysis of their α-hydroxy acid derivatives.

    PubMed

    Pleissner, Daniel; Wimmer, Reinhard; Eriksen, Niels T

    2011-01-01

    In this paper we describe a novel method for quantification of amino acids. First, α-hydroxy acid derivatives of amino acids were formed after reaction with dinitrogen trioxide by the van Slyke reaction. Second, the α-hydroxy acid derivatives were separated on an Aminex HPX-87H column (Bio-Rad) eluted isocratically with 5 mM H(2)SO(4) and quantified by refractive index detection. We were able to measure the reaction products of 13 of the 20 classical amino acids: glycine, l-alanine, l-valine, l-leucine, l-isoleucine, l-methionine, l-serine, l-threonine, l-asparagine, l-glutamine, l-aspartic acid, l-glutamic acid, and l-proline. We obtained linear relationships between the product peak areas and initial amino acid concentration, whereby the concentrations of these amino acids could be quantified on the basis of the quantification of their products. The method can be used to analyze amino acids in parallel with other small molecules, such as sugars or short chain fatty acids, and was used for parallel quantification of glycine, l-alanine, or l-glutamic acid, and glucose uptake in cultures of the heterotrophic dinoflagellate Crypthecodinium cohnii . The method can also be used to quantify other amines, as demonstrated by detection of Tris (2-amino-2-(hydroxymethyl)propane-1,3-diol).

  16. Circulating Levels of Hormones, Lipids, and Immune Mediators in Post-Traumatic Stress Disorder – A 3-Month Follow-Up Study

    PubMed Central

    Jergović, Mladen; Bendelja, Krešo; Savić Mlakar, Ana; Vojvoda, Valerija; Aberle, Neda; Jovanovic, Tanja; Rabatić, Sabina; Sabioncello, Ante; Vidović, Anđelko

    2015-01-01

    A number of peripheral blood analytes have been proposed as potential biomarkers of post-traumatic stress disorder (PTSD). Few studies have investigated whether observed changes in biomarkers persist over time. The aim of this study was to investigate the association of combat-related chronic PTSD with a wide array of putative PTSD biomarkers and to determine reliability of the measurements, i.e., correlations over time. Croatian combat veterans with chronic PTSD (n = 69) and age-matched healthy controls (n = 32), all men, were assessed at two time points separated by 3 months. Serum levels of lipids, cortisol, dehydroepiandrosterone-sulfate (DHEA-S), prolactin, and C-reactive protein were determined. Multiplex assay was used for the simultaneous assessment of 13 analytes in sera: cytokines [interferon-γ, interleukin (IL)-1β, IL-2, IL-4, IL-6, TNF-α], adhesion molecules (sPECAM-1, sICAM-1), chemokines (IL-8 and MIP-1α), sCD40L, nerve growth factor, and leptin. Group differences and changes over time were tested by parametric or non-parametric tests, including repeated measures analysis of covariance. Reliability estimates [intraclass correlation coefficient (ICC) and kappa] were also calculated. Robust associations of PTSD with higher levels of DHEA-S [F(1,75) = 8.14, p = 0.006)] and lower levels of prolactin [F(1,75) = 5.40, p = 0.023] were found. Measurements showed good to excellent reproducibility (DHEA-S, ICC = 0.50; prolactin, ICC = 0.79). Serum lipids did not differ between groups but significant increase of LDL-C after 3 months was observed in the PTSD group (t = 6.87, p < 0.001). IL-8 was lower in the PTSD group (t = 4.37, p < 0.001) but assessments showed poor reproducibility (ICC = −0.08). Stable DHEA-S and prolactin changes highlight their potential to be reliable markers of PTSD. Change in lipid profiles after 3 months suggests that PTSD patients may be more prone to hyperlipidemia. High

  17. Effect of Probiotic Soy Milk on Serum Levels of Adiponectin, Inflammatory Mediators, Lipid Profile, and Fasting Blood Glucose Among Patients with Type II Diabetes Mellitus.

    PubMed

    Feizollahzadeh, Sadegh; Ghiasvand, Reza; Rezaei, Abbas; Khanahmad, Hossein; Sadeghi, Akram; Hariri, Mitra

    2017-03-01

    Probiotic therapies are going to be an effective alternative therapeutic strategy in the treatment and management of diabetes. The mechanism behind the essential effects of probiotic therapies in diabetic patients was not fully understood. The objective of this study was to evaluate the effects of probiotic soy milk containing Lactobacillus planetarum A7 on inflammation, lipid profile, fasting blood glucose, and serum adiponectin among patients with type 2 diabetes mellitus. Forty patients with type 2 diabetes, at the age of 35-68 years old, were assigned to two groups in this randomized, double-blind, controlled clinical trial. The patients in the intervention group consumed 200 ml/day of probiotic soy milk containing L. planetarum A7 and those in control group consumed 200 ml/day of pure soy milk for 8 weeks. Serum TNF-α, C reactive protein, adiponectin, lipid profile, and fasting blood glucose were determined before and after intervention. In intervention group, serum adiponectin in pre- and post-treatment did not show any significant changes (2.52 ± 0.74 vs 2.84 ± 0.61, P = 0.658), as well as changes in serum TNF-α and C reactive protein (172.44 ± 5.7 vs 172.83 ± 7.6, P = 0.278, 4.2 ± 1.4 vs 4.5 ± 1.9, P = 0.765, respectively). Low-density cholesterol and high-density cholesterol changed significantly (P = 0.023, P = 0.017, respectively), but fasting blood glucose did not show any significant changes. The results of this study showed that consumption of probiotic soy milk and soy milk has no effect on serum adiponectin and inflammation, but it can change lipid profile among type 2 diabetic patients.

  18. Solid lipid nanoparticles with TPGS and Brij 78: A co-delivery vehicle of curcumin and piperine for reversing P-glycoprotein-mediated multidrug resistance in vitro

    PubMed Central

    Tang, Jingling; Ji, Hongyu; Ren, Jinmei; Li, Mengting; Zheng, Nannan; Wu, Linhua

    2017-01-01

    Multidrug resistance (MDR) is a main clinical hurdle for chemotherapy of cancer, and overexpression of P-glycoprotein (P-gp) is a key factor. In the present study, a new co-delivery system for reversing MDR was designed and developed. The system was composed of curcumin (Cur) and piperine (Pip) encapsulated in solid lipid nanoparticles (SLNs) with tocopheryl polyethylene glycol succinate (TPGS) and Brij 78 [(Cur+Pip)-SLNs]. TPGS and Brij 78 could sensitize MDR tumors by inhibiting the P-gp drug efflux system. The combination of Cur and Pip, when administered in SLNs formulations, resulted in a significant enhancement in cytotoxicity and allowed efficient intracellular delivery of the drugs in drug-resistant A2780/Taxol cells. This dual inhibitory strategy may have significant potential in the clinical management of MDR in cancer. PMID:28123572

  19. Curcuma longa polyphenols improve insulin-mediated lipid accumulation and attenuate proinflammatory response of 3T3-L1 adipose cells during oxidative stress through regulation of key adipokines and antioxidant enzymes.

    PubMed

    Septembre-Malaterre, Axelle; Le Sage, Fanny; Hatia, Sarah; Catan, Aurélie; Janci, Laurent; Gonthier, Marie-Paule

    2016-07-08

    Plant polyphenols may exert beneficial action against obesity-related oxidative stress and inflammation which promote insulin resistance. This study evaluated the effect of polyphenols extracted from French Curcuma longa on 3T3-L1 adipose cells exposed to H2 O2 -mediated oxidative stress. We found that Curcuma longa extract exhibited high amounts of curcuminoids identified as curcumin, demethoxycurcumin, and bisdemethoxycurcumin, which exerted free radical-scavenging activities. Curcuma longa polyphenols improved insulin-mediated lipid accumulation and upregulated peroxisome proliferator-activated receptor-gamma gene expression and adiponectin secretion which decreased in H2 O2 -treated cells. Curcuminoids attenuated H2 O2 -enhanced production of pro-inflammatory molecules such as interleukin-6, tumor necrosis factor-alpha, monocyte chemoattractant protein-1, and nuclear factor κappa B. Moreover, they reduced intracellular levels of reactive oxygen species elevated by H2 O2 and modulated the expression of genes encoding superoxide dismutase and catalase antioxidant enzymes. Collectively, these findings highlight that Curcuma longa polyphenols protect adipose cells against oxidative stress and may improve obesity-related metabolic disorders. © 2016 BioFactors, 42(4):418-430, 2016.

  20. Lipid Nanotechnology

    PubMed Central

    Mashaghi, Samaneh; Jadidi, Tayebeh; Koenderink, Gijsje; Mashaghi, Alireza

    2013-01-01

    Nanotechnology is a multidisciplinary field that covers a vast and diverse array of devices and machines derived from engineering, physics, materials science, chemistry and biology. These devices have found applications in biomedical sciences, such as targeted drug delivery, bio-imaging, sensing and diagnosis of pathologies at early stages. In these applications, nano-devices typically interface with the plasma membrane of cells. On the other hand, naturally occurring nanostructures in biology have been a source of inspiration for new nanotechnological designs and hybrid nanostructures made of biological and non-biological, organic and inorganic building blocks. Lipids, with their amphiphilicity, diversity of head and tail chemistry, and antifouling properties that block nonspecific binding to lipid-coated surfaces, provide a powerful toolbox for nanotechnology. This review discusses the progress in the emerging field of lipid nanotechnology. PMID:23429269

  1. New highly toxic bile acids derived from deoxycholic acid, chenodeoxycholic acid and lithocholic acid.

    PubMed

    Májer, Ferenc; Sharma, Ruchika; Mullins, Claire; Keogh, Luke; Phipps, Sinead; Duggan, Shane; Kelleher, Dermot; Keely, Stephen; Long, Aideen; Radics, Gábor; Wang, Jun; Gilmer, John F

    2014-01-01

    We have prepared a new panel of 23 BA derivatives of DCA, chenodeoxycholic acid (CDCA) and lithocholic acid (LCA) in order to study the effect of dual substitution with 3-azido and 24-amidation, features individually associated with cytotoxicity in our previous work. The effect of the compounds on cell viability of HT-1080 and Caco-2 was studied using the 3-[4,5-dimethylthizol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Compounds with high potency towards reduction of cell viability were further studied using flow cytometry in order to understand the mechanism of cell death. Several compounds were identified with low micromolar IC₅₀ values for reducing cell viability in the Caco-2 and HT1080 cell lines, making them among the most potent BA apoptotic agents reported to date. There was no evidence of relationship between overall hydrophobicity and cytotoxicity supporting the idea that cell death induction by BAs may be structure-specific. Compounds derived from DCA caused cell death through apoptosis. There was some evidence of selectivity between the two cell lines studied which may be due to differing expression of CD95/FAS. The more toxic compounds increased ROS production in Caco-2 cells, and co-incubation with the antioxidant N-acetyl cysteine blunted pro-apoptotic effects. The properties these compounds suggest that there may be specific mechanism(s) mediating BA induced cell death. Compound 8 could be useful for investigating this phenomenon.

  2. Effect of eicosapentaenoic acid-derived prostaglandin E3 on intestinal epithelial barrier function.

    PubMed

    Rodríguez-Lagunas, Maria J; Ferrer, Ruth; Moreno, Juan J

    2013-05-01

    Prostaglandins (PG) are inflammatory mediators derived from arachidonic or eicosapentaenoic acid giving rise to the 2-series or the 3-series prostanoids, respectively. Previously, we have observed that PGE2 disrupts epithelial barrier function. Considering the beneficial effect of fish oil consumption in intestinal inflammatory processes, the aim of this study was to assess the role of PGE3 on epithelial barrier function assessed from transepithelial electrical resistance and dextran fluxes in Caco-2 cells. The results indicate that PGE3 increased paracellular permeability (PP) to the same extent as PGE2, through the interaction with EP1 and EP4 receptors and with intracellular Ca(2+) and cAMP as the downstream targets. Moreover, we observed a redistribution of tight junction proteins, occludin and claudin-4. In conclusion, PGE3 is able to increase PP thus leading to reconsider the role of PGE2/PGE3 ratio in the beneficial effects of dietary fish oil supplementation in the disruption of barrier function.

  3. Persistent Nociception Triggered by Nerve Growth Factor (NGF) Is Mediated by TRPV1 and Oxidative Mechanisms.

    PubMed

    Eskander, Michael A; Ruparel, Shivani; Green, Dustin P; Chen, Paul B; Por, Elaine D; Jeske, Nathaniel A; Gao, Xiaoli; Flores, Eric R; Hargreaves, Kenneth M

    2015-06-03

    Nerve growth factor (NGF) is elevated in certain chronic pain conditions and is a sufficient stimulus to cause lasting pain in humans, but the actual mechanisms underlying the persistent effects of NGF remain incompletely understood. We developed a rat model of NGF-induced persistent thermal hyperalgesia and mechanical allodynia to determine the role of transient receptor potential vanilloid 1 (TRPV1) and oxidative mechanisms in the persistent effects of NGF. Persistent thermal hypersensitivity and mechanical allodynia require de novo protein translation and are mediated by TRPV1 and oxidative mechanisms. By comparing effects after systemic (subcutaneous), spinal (intrathecal) or hindpaw (intraplantar) injections of test compounds, we determined that TRPV1 and oxidation mediate persistent thermal hypersensitivity via peripheral and spinal sites of action and mechanical allodynia via only a spinal site of action. Therefore, NGF-evoked thermal and mechanical allodynia are mediated by spatially distinct mechanisms. NGF treatment evoked sustained increases in peripheral and central TRPV1 activity, as demonstrated by increased capsaicin-evoked nocifensive responses, increased calcitonin gene-related peptide release from hindpaw skin biopsies, and increased capsaicin-evoked inward current and membrane expression of TRPV1 protein in dorsal root ganglia neurons. Finally, we showed that NGF treatment increased concentrations of linoleic and arachidonic-acid-derived oxidized TRPV1 agonists in spinal cord and skin biopsies. Furthermore, increases in oxidized TRPV1-active lipids were reduced by peripheral and spinal injections of compounds that completely blocked persistent nociception. Collectively, these data indicate that NGF evokes a persistent nociceptive state mediated by increased TRPV1 activity and oxidative mechanisms, including increased production of oxidized lipid TRPV1 agonists.

  4. Carbon–carbon bond cleavage for Cu-mediated aromatic trifluoromethylations and pentafluoroethylations

    PubMed Central

    Sugiishi, Tsuyuka; Aikawa, Kohsuke

    2015-01-01

    Summary This short review highlights the copper-mediated fluoroalkylation using perfluoroalkylated carboxylic acid derivatives. Carbon–carbon bond cleavage of perfluoroalkylated carboxylic acid derivatives takes place in fluoroalkylation reactions at high temperature (150–200 °C) or under basic conditions to generate fluoroalkyl anion sources for the formation of fluoroalkylcopper species. The fluoroalkylation reactions, which proceed through decarboxylation or tetrahedral intermediates, are useful protocols for the synthesis of fluoroalkylated aromatics. PMID:26734112

  5. pH-Responsive therapeutic solid lipid nanoparticles for reducing P-glycoprotein-mediated drug efflux of multidrug resistant cancer cells.

    PubMed

    Chen, Hsin-Hung; Huang, Wen-Chia; Chiang, Wen-Hsuan; Liu, Te-I; Shen, Ming-Yin; Hsu, Yuan-Hung; Lin, Sung-Chyr; Chiu, Hsin-Cheng

    2015-01-01

    In this study, a novel pH-responsive cholesterol-PEG adduct-coated solid lipid nanoparticles (C-PEG-SLNs) carrying doxorubicin (DOX) capable of overcoming multidrug resistance (MDR) breast cancer cells is presented. The DOX-loaded SLNs have a mean hydrodynamic diameter of ~100 nm and a low polydispersity index (under 0.20) with a high drug-loading efficiency ranging from 80.8% to 90.6%. The in vitro drug release profiles show that the DOX-loaded SLNs exhibit a pH-controlled drug release behavior with the maximum and minimum unloading percentages of 63.4% at pH 4.7 and 25.2% at pH 7.4, respectively. The DOX-loaded C-PEG-SLNs displayed a superior ability in inhibiting the proliferation of MCF-7/MDR cells. At a DOX concentration of 80 μM, the cell viabilities treated with C-PEG-SLNs were approximately one-third of the group treated with free DOX. The inhibition activity of C-PEG-SLNs could be attributed to the transport of C-PEG to cell membrane, leading to the change of the composition of the cell membrane and thus the inhibition of permeability glycoprotein activity. This hypothesis is supported by the confocal images showing the accumulation of DOX in the nuclei of cancer cells and the localization of C-PEG on the cell membranes. The results of in vivo study further demonstrated that the DOX delivered by the SLNs accumulates predominantly in tumor via enhanced permeability and retention effect, the enhanced passive tumor accumulation due to the loose intercellular junctions of endothelial cells lining inside blood vessels at tumor site, and the lack of lymphatic drainage. The growth of MCF-7/MDR xenografted tumor on Balb/c nude mice was inhibited to ~400 mm(3) in volume as compared with the free DOX treatment group, 1,140 mm(3), and the group treated with 1,2 distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)] solid lipid nanoparticles, 820 mm(3). Analysis of the body weight of nude mice and the histology of organs and tumor after the

  6. Nanostructured lipid carriers loaded with CoQ10: effect on human dermal fibroblasts under normal and UVA-mediated oxidative conditions.

    PubMed

    Brugè, Francesca; Damiani, Elisabetta; Puglia, Carmelo; Offerta, Alessia; Armeni, Tatiana; Littarru, Gian Paolo; Tiano, Luca

    2013-10-15

    Nanostructured lipid carriers (NLC) represent an emerging tool for drug delivery and are characterized by important features which promote increased bioavailability and epithelial penetration of lipophilic compounds. However, despite these advantages, their potential cytotoxicity should not be underestimated, especially under in vivo usage conditions. Here we analyzed the viability, intracellular reactive oxygen species (ROS), oxidative DNA damage and mitochondrial functionality in human dermal fibroblasts (HDF) in the presence of NLC either empty or loaded with the reduced or oxidized form of Coenzyme Q10. Experiments were carried out under standard culture conditions and under oxidative stress induced by UVA irradiation, where the latter treatment significantly affected all the endpoints tested above compared to the non-UVA condition. The data show that NLC alone, whether exposed or not exposed to UVA, produce a slight, though significant decrease in cell viability associated with enhanced oxidative stress, which did not however lead to oxidative DNA damage nor mitochondrial impairment. Reduced CoQ10-NLC, differently from oxidized CoQ10-NLC, were able to efficiently counteract UVA-associated mitochondrial depolarization suggesting a potential role of this molecule in antiageing cosmetological formulations. In conclusion, our results suggest that interactions of NLC with cells and biomolecules should be routinely assessed for understanding their compatibility and toxicity, not only under normal conditions, but also under any chemical or physical stress which these delivery systems might be subjected to during their employment.

  7. A Shigella effector dampens inflammation by regulating epithelial release of danger signal ATP through production of the lipid mediator PtdIns5P.

    PubMed

    Puhar, Andrea; Tronchère, Hélène; Payrastre, Bernard; Nhieu, Guy Tran Van; Sansonetti, Philippe J

    2013-12-12

    Upon infection with Shigella flexneri, epithelial cells release ATP through connexin hemichannels. However, the pathophysiological consequence and the regulation of this process are unclear. Here we showed that in intestinal epithelial cell ATP release was an early alert response to infection with enteric pathogens that eventually promoted inflammation of the gut. Shigella evolved to escape this inflammatory reaction by its type III secretion effector IpgD, which blocked hemichannels via the production of the lipid PtdIns5P. Infection with an ipgD mutant resulted in rapid hemichannel-dependent accumulation of extracellular ATP in vitro and in vivo, which preceded the onset of inflammation. At later stages of infection, ipgD-deficient Shigella caused strong intestinal inflammation owing to extracellular ATP. We therefore describe a new paradigm of host-pathogen interaction based on endogenous danger signaling and identify extracellular ATP as key regulator of mucosal inflammation during infection. Our data provide new angles of attack for the development of anti-inflammatory molecules.

  8. The crystal structure of Atg3, an autophagy-related ubiquitin carrier protein (E2) enzyme that mediates Atg8 lipidation.

    PubMed

    Yamada, Yuya; Suzuki, Nobuo N; Hanada, Takao; Ichimura, Yoshinobu; Kumeta, Hiroyuki; Fujioka, Yuko; Ohsumi, Yoshinori; Inagaki, Fuyuhiko

    2007-03-16

    Atg3 is an E2-like enzyme that catalyzes the conjugation of Atg8 and phosphatidylethanolamine (PE). The Atg8-PE conjugate is essential for autophagy, which is the bulk degradation process of cytoplasmic components by the vacuolar/lysosomal system. We report here the crystal structure of Saccharomyces cerevisiae Atg3 at 2.5-A resolution. Atg3 has an alpha/beta-fold, and its core region is topologically similar to canonical E2 enzymes. Atg3 has two regions inserted in the core region, one of which consists of approximately 80 residues and has a random coil structure in solution and another with a long alpha-helical structure that protrudes from the core region as far as 30 A. In vivo and in vitro analyses suggested that the former region is responsible for binding Atg7, an E1-like enzyme, and that the latter is responsible for binding Atg8. A sulfate ion was bound near the catalytic cysteine of Atg3, suggesting a possible binding site for the phosphate moiety of PE. The structure of Atg3 provides a molecular basis for understanding the unique lipidation reaction that Atg3 carries out.

  9. Boronic acid-tethered amphiphilic hyaluronic acid derivative-based nanoassemblies for tumor targeting and penetration.

    PubMed

    Jeong, Jae Young; Hong, Eun-Hye; Lee, Song Yi; Lee, Jae-Young; Song, Jae-Hyoung; Ko, Seung-Hak; Shim, Jae-Seong; Choe, Sunghwa; Kim, Dae-Duk; Ko, Hyun-Jeong; Cho, Hyun-Jong

    2017-02-16

    (3-Aminomethylphenyl)boronic acid (AMPB)-installed hyaluronic acid-ceramide (HACE)-based nanoparticles (NPs), including manassantin B (MB), were fabricated for tumor-targeted delivery. The amine group of AMPB was conjugated to the carboxylic acid group of hyaluronic acid (HA) via amide bond formation, and synthesis was confirmed by spectroscopic methods. HACE-AMPB/MB NPs with a 239-nm mean diameter, narrow size distribution, negative zeta potential, and >90% drug encapsulation efficiency were fabricated. Exposed AMPB in the outer surface of HACE-AMPB NPs (in the aqueous environment) may react with sialic acid of cancer cells. The improved cellular accumulation efficiency, in vitro antitumor efficacy, and tumor penetration efficiency of HACE-AMPB/MB NPs, compared with HACE/MB NPs, in MDA-MB-231 cells (CD44 receptor-positive human breast adenocarcinoma cells) may be based on the CD44 receptor-mediated endocytosis and phenylboronic acid-sialic acid interaction. Enhanced in vivo tumor targetability, infiltration efficiency, and antitumor efficacies of HACE-AMPB NPs, compared with HACE NPs, were observed in a MDA-MB-231 tumor-xenografted mouse model. In addition to passive tumor targeting (based on an enhanced permeability and retention effect) and active tumor targeting (interaction between HA and CD44 receptor), the phenylboronic acid-sialic acid interaction can play important roles in augmented tumor targeting and penetration of HACE-AMPB NPs. STATEMENT OF SIGNIFICANCE: (3-Aminomethylphenyl)boronic acid (AMPB)-tethered hyaluronic acid-ceramide (HACE)-based nanoparticles (NPs), including manassantin B (MB), were fabricated and their tumor targeting and penetration efficiencies were assessed in MDA-MB-231 (CD44 receptor-positive human adenocarcinoma) tumor models. MB, which exhibited antitumor efficacies via the inhibition of angiogenesis and hypoxia inducible factor (HIF)-1, was entrapped in HACE-AMPB NPs in this study. Phenylboronic acid located in the outer surface

  10. Effects of structural differences on the NMR chemical shifts in cinnamic acid derivatives: Comparison of GIAO and GIPAW calculations

    NASA Astrophysics Data System (ADS)

    Szeleszczuk, Łukasz; Pisklak, Dariusz Maciej; Zielińska-Pisklak, Monika; Wawer, Iwona

    2016-06-01

    In this article we report the results of combined theoretical and experimental structural studies on cinnamic acid derivatives (CADs), one of the main groups of secondary metabolites present in various medicinal plant species and food products of plant origin. The effects of structural differences in CADs on their spectroscopic properties were studied in detail by both: solid-state NMR and GIAO/GIPAW calculations. Theoretical computations were used in order to perform signal assignment in 13C CP/MAS NMR spectra of the cinnamic, o-coumaric, m-coumaric, p-coumaric, caffeic, ferulic, sinapic and 3,4-dimethoxycinnamic acids, and to evaluate the accuracy of GIPAW and GIAO methodology.

  11. Design, synthesis and molecular docking of salicylic acid derivatives containing metronidazole as a new class of antimicrobial agents.

    PubMed

    Guo, Zhi-Hua; Yin, Yong; Wang, Cong; Wang, Peng-Fei; Zhang, Xing-Tao; Wang, Zhong-Chang; Zhu, Hai-Liang

    2015-09-15

    A series of novel salicylic acid derivatives containing metronidazole as Staphylococcus aureus Tyrosyl-tRNA synthetase (TyrRS) inhibitors have been synthesized and evaluated their biology activities as potential antibacterial agents. Among these compounds, compound 5r exhibited the most potent antibacterial activity against Gram-positive (S. aureus ATCC 6538 and Bacillus subtilis ATCC 6633) and Gram-negative (Escherichia coli ATCC 35218 and Pseudomonas aeruginosa ATCC 13525) with MICs of 0.39-1.57 μg/mL and showed the most potent S. aureus Tyrosyl-tRNA synthetase inhibitory with 2.3 μM. Docking simulation was performed to insert compound 5r into the crystal structure of S. aureus Tyrosyl-tRNA synthetase active site to determine the probable binding model. These results suggested that compound 5r may be a promising antibacterial agent.

  12. Determination of drug-polymer binding constants by affinity capillary electrophoresis for aryl propionic acid derivatives and related compounds.

    PubMed

    Jia, Zhongjiang; Choi, Duk Soon; Chokshi, Hitesh

    2013-03-01

    The binding constants (K(b)s) of 17 aryl propionic acid derivatives (APADs) and related compounds with polyvinylpyrrolidone (PVP K30) and vinylpyrrolidone-vinyl acetate copolymer (Kollidon VA64) in aqueous media were determined by affinity capillary electrophoreses (ACE). The K(b)s of APAD to polymers increase with octanol-water partition coefficients of the compounds. Kollidon VA64 is a stronger binder than PVP K30 to APAD compounds. The K(b)s are greater at pH 4 than at pH 9. Both hydrophobic interaction and hydrogen bonding may be involved. However, hydrophobic interaction appears to be dominant. The ACE method is simple and fast, which could be used to study drug-polymer interaction in aqueous media.

  13. The anti-ageing potential of a new jasmonic acid derivative (LR2412): in vitro evaluation using reconstructed epidermis Episkin™.

    PubMed

    Michelet, Jean F; Olive, Christian; Rieux, Elodie; Fagot, Dominique; Simonetti, Lucie; Galey, Jean B; Dalko-Csiba, Maria; Bernard, Bruno A; Pereira, Rui

    2012-05-01

    Jasmonic acid is involved in plant wound repair and tissue regeneration, but no study has been reported in human skin. The effect of a jasmonic acid derivative, tetra-hydro-jasmonic acid (LR2412, 1 and 10 μm) was investigated on an in vitro reconstructed skin model, Episkin™. Using real time RTQPCR studies, results showed an increase in hyaluronan synthase 2 (HAS2) and hyaluronase synthase 3 (HAS3) expression. Furthermore, an increase in hyaluronic acid (HA) deposits in basal and suprabasal layers of the epidermis was observed. The percentage of positive Ki67 keratinocytes in the basal layer as well as the epidermis thickness were seen to increase. Immunohistochemistry studies showed that the synthesis of late differentiation proteins filaggrin and transglutaminase 1 was not modified. The human epidermis is known to thin with age while HA content has been reported to decrease. These results illustrate the potential of LR2412 in counteracting signs of skin ageing.

  14. The antimicrobial efficacy and structure activity relationship of novel carbohydrate fatty acid derivatives against Listeria spp. and food spoilage microorganisms.

    PubMed

    Nobmann, Patricia; Smith, Aoife; Dunne, Julie; Henehan, Gary; Bourke, Paula

    2009-01-15

    Novel mono-substituted carbohydrate fatty acid (CFA) esters and ethers were investigated for their antibacterial activity against a range of pathogenic and spoilage bacteria focussing on Listeria monocytogenes. Carbohydrate derivatives with structural differences enable comparative studies on the structure/activity relationship for antimicrobial efficacy and mechanism of action. The antimicrobial efficacy of the synthesized compounds was compared with commercially available compounds such as monolaurin and monocaprylin, as well as the pure free fatty acids, lauric acid and caprylic acid, which have proven antimicrobial activity. Compound efficacy was compared using an absorbance based broth microdilution assay to determine the minimum inhibitory concentration (MIC), increase in lag phase and decrease in maximum growth rate. Among the carbohydrate derivatives synthesized, lauric ether of methyl alpha-d-glucopyranoside and lauric ester of methyl alpha-d-mannopyranoside showed the highest growth-inhibitory effect with MIC values of 0.04 mM, comparable to monolaurin. CFA derivatives were generally more active against Gram positive bacteria than Gram negative bacteria. The analysis of both ester and ether fatty acid derivatives of the same carbohydrate, in tandem with alpha and beta configuration of the carbohydrate moiety suggest that the carbohydrate moiety is involved in the antimicrobial activity of the fatty acid derivatives and that the nature of the bond also has a significant effect on efficacy, which requires further investigation. This class of CFA derivatives has great potential for developing antibacterial agents relevant to the food industry, particularly for control of Listeria or other Gram-positive pathogens.

  15. Fisetin Suppresses Lipid Accumulation in Mouse Adipocytic 3T3-L1 Cells by Repressing GLUT4-Mediated Glucose Uptake through Inhibition of mTOR-C/EBPα Signaling.

    PubMed

    Watanabe, Marina; Hisatake, Mitsuhiro; Fujimori, Ko

    2015-05-27

    3,7,3',4'-Tetrahydroxyflavone (fisetin) is a flavonoid found in vegetables and fruits having broad biological activities. Here the effects of fisetin on adipogenesis and its regulatory mechanism in mouse adipocytic 3T3-L1 cells are studied. Fisetin inhibited the accumulation of intracellular lipids and lowered the expression of adipogenic genes such as peroxisome proliferator-activated receptor γ and CCAAT/enhancer-binding protein (C/EBP) α and fatty acid-binding protein 4 (aP2) during adipogenesis. Moreover, the mRNA levels of genes such as acetyl-CoA carboxylase, fatty acid synthase, and stearoyl-CoA desaturase involved in the fatty acid biosynthesis (lipogenesis) were reduced by the treatment with fisetin. The expression level of the glucose transporter 4 (GLUT4) gene was also decreased by fisetin, resulting in down-regulation of glucose uptake. Furthermore, fisetin inhibited the phosphorylation of the mammalian target of rapamycin (mTOR) and that of p70 ribosomal S6 kinase, a target of the mTOR complex, the inhibition of which was followed by a decreased mRNA level of the C/EBPα gene. The results obtained from a chromatin immunoprecipitation assay demonstrated that the ability of C/EBPα to bind to the GLUT4 gene promoter was reduced by the treatment with fisetin, which agreed well with those obtained when 3T3-L1 cells were allowed to differentiate into adipocytes in medium in the presence of rapamycin, an inhibitor for mTOR. These results indicate that fisetin suppressed the accumulation of intracellular lipids by inhibiting GLUT4-mediated glucose uptake through inhibition of the mTOR-C/EBPα signaling in 3T3-L1 cells.

  16. Rimonabant-mediated changes in intestinal lipid metabolism and improved renal vascular dysfunction in the JCR:LA-cp rat model of prediabetic metabolic syndrome.

    PubMed

    Russell, James C; Kelly, Sandra E; Diane, Abdoulaye; Wang, Ye; Mangat, Rabban; Novak, Susan; Vine, Donna F; Proctor, Spencer D

    2010-08-01

    Rimonabant (SR141716) is a specific antagonist of the cannabinoid-1 receptor. Activation of the receptor initiates multiple effects on central nervous system function, metabolism, and body weight. The hypothesis that rimonabant has protective effects against vascular disease associated with the metabolic syndrome was tested using JCR:LA-cp rats. JCR:LA-cp rats are obese if they are cp/cp, insulin resistant, and exhibit associated micro- and macrovascular disease with end-stage myocardial and renal disease. Treatment of obese rats with rimonabant (10 mg.kg(-1).day(-1), 12-24 wk of age) caused transient reduction in food intake for 2 wk, without reduction in body weight. However, by 4 wk, there was a modest, sustained reduction in weight gain. Glycemic control improved marginally compared with controls, but at the expense of increased insulin concentration. In contrast, rimonabant normalized fasting plasma triglyceride and reduced plasma plasminogen activator inhibitor-1 and acute phase protein haptoglobin in cp/cp rats. Furthermore, these changes were accompanied by reduced postprandial intestinal lymphatic secretion of apolipoprotein B48, cholesterol, and haptoglobin. While macrovascular dysfunction and ischemic myocardial lesion frequency were unaffected by rimonabant treatment, both microalbuminuria and glomerular sclerosis were substantially reduced. In summary, rimonabant has a modest effect on body weight in freely eating obese rats and markedly reduces plasma triglyceride levels and microvascular disease, in part due to changes in intestinal metabolism, including lymphatic secretion of apolipoprotein B48 and haptoglobin. We conclude that rimonabant improves renal disease and intestinal lipid oversecretion associated with an animal model of the metabolic syndrome that appears to be independent of hyperinsulinemia or macrovascular dysfunction.

  17. Emerging targets in lipid-based therapy☆

    PubMed Central

    Tucker, Stephanie C.; Honn, Kenneth V.

    2013-01-01

    The use of prostaglandins and NSAIDS in the clinic has proven that lipid mediators and their associated pathways make attractive therapeutic targets. When contemplating therapies involving lipid pathways, several basic agents come to mind. There are the enzymes and accessory proteins that lead to the metabolism of lipid substrates, provided through diet or through actions of lipases, the subsequent lipid products, and finally the lipid sensors or receptors. There is abundant evidence that molecules along this lipid continuum can serve as prognostic and diagnostic indicators and are in fact viable therapeutic targets. Furthermore, lipids themselves can be used as therapeutics. Despite this, the vernacular dialog pertaining to “biomarkers” does not routinely include mention of lipids, though this is rapidly changing. Collectively these agents are becoming more appreciated for their respective roles in diverse disease processes from cancer to preterm labor and are receiving their due appreciation after decades of ground work in the lipid field. By relating examples of disease processes that result from dysfunction along the lipid continuum, as well as examples of lipid therapies and emerging technologies, this review is meant to inspire further reading and discovery. PMID:23261527

  18. Quantitative Profiling of Hydroxy Lipid Metabolites in Mouse Organs Reveals Distinct Lipidomic Profiles and Modifications Due to Elevated n-3 Fatty Acid Levels

    PubMed Central

    Chiu, Cheng-Ying; Smyl, Christopher; Dogan, Inci; Rothe, Michael; Weylandt, Karsten-H.

    2017-01-01

    Polyunsaturated fatty acids (PUFA) are precursors of bioactive metabolites and mediators. In this study, the profile of hydroxyeicosatetraenoic (HETE), hydroxyeicosapentaenoic (HEPE) and hydroxydocosahexaenoic (HDHA) acids derived from arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in colon, liver, lung, spleen, muscle, heart and kidney tissue of healthy wildtype mice were characterized, and compared to profiles in organs from transgenic fat-1 mice engineered to express the Caenorhabditis elegans fat-1 gene encoding an n-3 desaturase and thereby with endogenously elevated n-3 PUFA levels. PUFAs were measured using gas chromatography. The lipid metabolites were assayed using LC-MS/MS. AA and DHA were the prominent PUFAs in wildtype and fat-1 mice. EPA levels were low in both groups even though there was a significant increase in fat-1 organs with an up to 12-fold increase in fat-1 spleen and kidney. DHA levels increased by approximately 1.5-fold in fat-1 as compared to wildtype mice. While HETEs remained the same or decreased moderately and HDHAs increased 1- to 3-fold, HEPE formation in fat-1 tissues increased from 8- (muscle) to 44-fold (spleen). These findings indicate distinct profiles of monohydroxy lipid metabolites in different organs and strong utilization of EPA for HEPE formation, by which moderate EPA supplementation might trigger formation of biologically active EPA-derived resolvins. PMID:28165385

  19. A pseudaminic acid or a legionaminic acid derivative transferase is strain-specifically implicated in the general protein O-glycosylation system of the periodontal pathogen Tannerella forsythia.

    PubMed

    Tomek, Markus B; Janesch, Bettina; Maresch, Daniel; Windwarder, Markus; Altmann, Friedrich; Messner, Paul; Schäffer, Christina

    2017-03-16

    The occurrence of nonulosonic acids in bacteria is wide-spread and linked to pathogenicity. However, the knowledge of cognate nonulosonic acid transferases is scarce. In the periodontopathogen Tannerella forsythia, several proposed virulence factors carry strain-specifically either a pseudaminic or a legionaminic acid derivative as terminal sugar on an otherwise structurally identical, protein-bound oligosaccharide. This study aims to shed light on the transfer of either nonulosonic acid derivative on a proximal N-acetylmannosaminuronic acid residue within the O-glycan structure, exemplified with the bacterium's abundant S-layer glycoproteins. Bioinformatic analyses provided the candidate genes Tanf_01245 (strain ATCC 43037) and TFUB4_00887 (strain UB4), encoding a putative pseudaminic and a legionaminic acid derivative transferase, respectively. These transferases have identical C-termini and contain motifs typical of glycosyltransferases (DXD) and bacterial sialyltransferases (D/E-D/E-G and HP). They share homology to type B glycosyltransferases and TagB, an enzyme catalyzing glycerol transfer to an N-acetylmannosamine residue in teichoic acid biosynthesis. Analysis of a cellular pool of nucleotide-activated sugars confirmed the presence of the CMP-activated nonulosonic acid derivatives, which are most likely serving as substrates for the corresponding transferase. Single gene knock-out mutants targeted at either transferase were analyzed for S-layer O-glycan composition by ESI-MS, confirming the loss of the nonulosonic acid derivative. Cross-complementation of the mutants with the nonnative nonulosonic acid transferase was not successful indicating high stringency of the enzymes. This study identified plausible candidates for a pseudaminic and a legionaminic acid derivative transferase; these may serve as valuable tools for engineering of novel sialoglycoconjugates.

  20. Cationic lipid-nanoceria hybrids, a novel nonviral vector-mediated gene delivery into mammalian cells: investigation of the cellular uptake mechanism

    PubMed Central

    Das, Joydeep; Han, Jae Woong; Choi, Yun-Jung; Song, Hyuk; Cho, Ssang-Goo; Park, Chankyu; Seo, Han Geuk; Kim, Jin-Hoi

    2016-01-01

    Gene therapy is a promising technique for the treatment of various diseases. The development of minimally toxic and highly efficient non-viral gene delivery vectors is the most challenging undertaking in the field of gene therapy. Here, we developed dimethyldioctadecylammonium bromide (DODAB)–nanoceria (CeO2) hybrids as a new class of non-viral gene delivery vectors. These DODAB-modified CeO2 nanoparticles (CeO2/DODAB) could effectively compact the pDNA, allowing for highly efficient gene transfection into the selected cell lines. The CeO2/DODAB nanovectors were also found to be non-toxic and did not induce ROS formation as well as any stress responsive and pro-survival signaling pathways. The overall vector performance of CeO2/DODAB nanohybrids was comparable with lipofectamine and DOTAP, and higher than calcium phosphate and DEAE-dextran for transfecting small plasmids. The increased cellular uptake of the nanovector/DNA complexes through clathrin- and caveolae-mediated endocytosis and subsequent release from the endosomes further support the increased gene transfection efficiency of the CeO2/DODAB vectors. Besides, CeO2/DODAB nanovectors could transfect genes in vivo without any sign of toxicity. Taken together, this new nano-vector has the potential to be used for gene delivery in biomedical applications. PMID:27380727

  1. [Effect of 3-oxypyridine and succinic acid derivatives on affective status in recrudescence of inflammatory diseases of uterus and its appendages].

    PubMed

    Volchegorskiĭ, I A; Pravdin, E V; Uzlova, T V

    2012-01-01

    Short-term, prospective placebo-controlled simple blind randomized study of the effects of 3-oxypyridine and succinic acid derivatives (emoxipin, reamberin, mexidol) on the affective status of females with recrudescence of the inflammatory diseases of uterus and its appendages (IDUA) in comparison to changes of systemic inflammatory response (SIR) markers level in the blood has been conducted. It is established that the inclusion of emoxipin, reamberin and mexidol in complex treatment of IDUA recrudescence reduce depression, anxiety and SIR laboratory signs. Mexidol being both 3-oxypyridine and succinic acid derivative showed the best influence on the dynamics of affective disorders and SIR changes.

  2. Lipid phase control of DNA delivery

    SciTech Connect

    Koynova, Rumiana; Wang, Li; Tarahovsky, Yury; MacDonald, Robert C.

    2010-01-18

    Cationic lipids form nanoscale complexes (lipoplexes) with polyanionic DNA and can be utilized to deliver DNA to cells for transfection. Here we report the correlation between delivery efficiency of these DNA carriers and the mesomorphic phases they form when interacting with anionic membrane lipids. Specifically, formulations that are particularly effective DNA carriers form phases of highest negative interfacial curvature when mixed with anionic lipids, whereas less effective formulations form phases of lower curvature. Structural evolution of the carrier lipid/DNA complexes upon interaction with cellular lipids is hence suggested as a controlling factor in lipid-mediated DNA delivery. A strategy for optimizing lipofection is deduced. The behavior of a highly effective lipoplex formulation, DOTAP/DOPE, is found to conform to this 'efficiency formula'.

  3. Comparative evaluation of 13 yeast species in the Yarrowia clade on lignocellulosic biomass hydrolysate and genetic engineering of inhibitor tolerant strains for lipid and biofuel production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yarrowia lipolytica is an oleaginous yeast that has garnered interest for commercial production of single cell oil and other fatty acid-derived chemicals because of its GRAS status and genetic tractability. Three recent peer-reviewed studies have highlighted the possibility of lipid production by th...

  4. 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.

  5. Design, synthesis and biological evaluation of 2-(substituted phenyl)thiazolidine-4-carboxylic acid derivatives as novel tyrosinase inhibitors.

    PubMed

    Ha, Young Mi; Park, Yun Jung; Lee, Ji Yeon; Park, Daeui; Choi, Yeon Ja; Lee, Eun Kyeong; Kim, Ji Min; Kim, Jin-Ah; Park, Ji Young; Lee, Hye Jin; Moon, Hyung Ryong; Chung, Hae Young

    2012-02-01

    Herein we describe the design, synthesis and biological activities of 2-(substituted phenyl)thiazolidine-4-carboxylic acid derivatives as novel tyrosinase inhibitors. The target compounds 2a-2j were designed and synthesized from the structural characteristics of N-phenylthiourea, tyrosinase inhibitor and tyrosine, and l-DOPA, the natural substrates of tyrosinase. Among them, (2R/S,4R)-2-(2,4-dimethoxyphenyl)thiazolidine-4-carboxylic acid (2g) caused the greatest inhibition 66.47% at 20 μM of l-DOPA oxidase activity of mushroom tyrosinase. Kinetic analysis of tyrosinase inhibition revealed that 2g is a competitive inhibitor. We predicted the tertiary structure of tyrosinase, and simulated the docking of mushroom tyrosinase with 2g. These results suggest that the binding affinity of 2g with tyrosinase is high. Also, 2g effectively inhibited tyrosinase activity and reduced melanin levels in B16 cells treated with α-MSH. These data strongly suggest that 2g can suppress the production of melanin via the inhibition of tyrosinase activity.

  6. Synthesis and evaluation of novel [alpha]-heteroaryl-phenylpropanoic acid derivatives as PPAR[alpha/gamma] dual agonists

    SciTech Connect

    Casimiro-Garcia, Agustin; Bigge, Christopher F.; Davis, Jo Ann; Padalino, Teresa; Pulaski, James; Ohren, Jeffrey F.; McConnell, Patrick; Kane, Christopher D.; Royer, Lori J.; Stevens, Kimberly A.; Auerbach, Bruce; Collard, Wendy; McGregor, Christine; Song, Kun; Pfizer

    2010-09-27

    The synthesis of a new series of phenylpropanoic acid derivatives incorporating an heteroaryl group at the {alpha}-position and their evaluation for binding and activation of PPAR{alpha} and PPAR{gamma} are presented in this report. Among the new compounds, (S)-3-{l_brace}4-[3-(5-methyl-2-phenyl-oxazol-4-yl)-propyl]-phenyl{r_brace}-2-1,2,3-triazol-2-yl-propionic acid (17j), was identified as a potent human PPAR{alpha}/{gamma} dual agonist (EC{sub 50} = 0.013 and 0.061 {micro}M, respectively) with demonstrated oral bioavailability in rat and dog. 17j was shown to decrease insulin levels, plasma glucose, and triglycerides in the ZDF female rat model. In the human apolipoprotein A-1/CETP transgenic mouse model 17j produced increases in hApoA1 and HDL-C and decreases in plasma triglycerides. The increased potency for binding and activation of both PPAR subtypes observed with 17j when compared to previous analogs in this series was explained based on results derived from crystallographic and modeling studies.

  7. Establishment of Hairy Root Cultures of Rhaponticum carthamoides (Willd.) Iljin for the Production of Biomass and Caffeic Acid Derivatives

    PubMed Central

    Skała, Ewa; Kicel, Agnieszka; Olszewska, Monika A.; Kiss, Anna K.

    2015-01-01

    The aim of the study was to obtain transformed roots of Rhaponticum carthamoides and evaluate their phytochemical profile. Hairy roots were induced from leaf explants by the transformation of Agrobacterium rhizogenes strains A4 and ATCC 15834. The best response (43%) was achieved by infection with A4 strain. The effects of different liquid media (WPM, B5, SH) with full and half-strength concentrations of macro- and micronutrients on biomass accumulation of the best grown hairy root line (RC3) at two different lighting conditions (light or dark) were investigated. The highest biomass (93 g L−1 of the fresh weight after 35 days) was obtained in WPM medium under periodic light. UPLC-PDA-ESI-MS3 and HPLC-PDA analyses of 80% aqueous methanol extracts from the obtained hairy roots revealed the presence of eleven caffeoylquinic acids and their derivatives and five flavonoid glycosides. The production of caffeoylquinic acids and their derivatives was elevated in hairy roots grown in the light. Only light-grown hairy roots demonstrated the capability for the biosynthesis of such flavonoid glycosides as quercetagetin, quercetin, luteolin, and patuletin hexosides. Chlorogenic acid, 3,5-di-O-caffeoylquinic acid and a tentatively identified tricaffeoylquinic acid derivative were detected as the major compounds present in the transformed roots. PMID:25811023

  8. Establishment of hairy root cultures of Rhaponticum carthamoides (Willd.) Iljin for the production of biomass and caffeic acid derivatives.

    PubMed

    Skała, Ewa; Kicel, Agnieszka; Olszewska, Monika A; Kiss, Anna K; Wysokińska, Halina

    2015-01-01

    The aim of the study was to obtain transformed roots of Rhaponticum carthamoides and evaluate their phytochemical profile. Hairy roots were induced from leaf explants by the transformation of Agrobacterium rhizogenes strains A4 and ATCC 15834. The best response (43%) was achieved by infection with A4 strain. The effects of different liquid media (WPM, B5, SH) with full and half-strength concentrations of macro- and micronutrients on biomass accumulation of the best grown hairy root line (RC3) at two different lighting conditions (light or dark) were investigated. The highest biomass (93 g L(-1) of the fresh weight after 35 days) was obtained in WPM medium under periodic light. UPLC-PDA-ESI-MS(3) and HPLC-PDA analyses of 80% aqueous methanol extracts from the obtained hairy roots revealed the presence of eleven caffeoylquinic acids and their derivatives and five flavonoid glycosides. The production of caffeoylquinic acids and their derivatives was elevated in hairy roots grown in the light. Only light-grown hairy roots demonstrated the capability for the biosynthesis of such flavonoid glycosides as quercetagetin, quercetin, luteolin, and patuletin hexosides. Chlorogenic acid, 3,5-di-O-caffeoylquinic acid and a tentatively identified tricaffeoylquinic acid derivative were detected as the major compounds present in the transformed roots.

  9. LBH589, A Hydroxamic Acid-Derived HDAC Inhibitor, is Neuroprotective in Mouse Models of Huntington’s Disease

    PubMed Central

    Chopra, Vanita; Quinti, Luisa; Khanna, Prarthana; Paganetti, Paolo; Kuhn, Rainer; Young, Anne B.; Kazantsev, Aleksey G.; Hersch, Steven

    2016-01-01

    Background: Modulation of gene transcription by HDAC inhibitors has been shown repeatedly to be neuroprotective in cellular, invertebrate, and rodent models of Huntington’s disease (HD). It has been difficult to translate these treatments to the clinic, however, because existing compounds have limited potency or brain bioavailability. Objective: In the present study, we assessed the therapeutic potential of LBH589, an orally bioavailable hydroxamic acid-derived nonselective HDAC inhibitor in mouse models of HD. Method: The efficacy of LBH589 is tested in two HD mouse models using various biochemical, behavioral and neuropathological outcome measures. Results: We show that LBH589 crosses the blood brain barrier; induces histone hyperacetylation and prevents striatal neuronal shrinkage in R6/2 HD mice. In full-length knock-in HD mice LBH589-treatment improves motor performance and reduces neuronal atrophy. Conclusions: Our efficacious results of LBH589 in fragment and full-length mouse models of HD suggest that LBH589 is a promising candidate for clinical assessment in HD patients and provides confirmation that non-selective HDAC inhibitors can be viable clinical candidates. PMID:27983565

  10. Precursor ion scan driven fast untargeted screening and semi-determination of caffeoylquinic acid derivatives in Cynara scolymus L.

    PubMed

    Shen, Qing; Lu, Yanbin; Dai, Zhiyuan; Cheung, Hon-Yeung

    2015-01-01

    A precursor ion scan (PIS) technique based strategy was developed for rapid screening and semi-determination of caffeoylquinic acid derivatives (CADs) in artichoke (Cynara scolymus L.) using ultra-performance liquid chromatography (UPLC) coupled with tandem mass spectrometry. 1,5-Dicaffeoylquinic acid and 5-caffeoylquinic acid were used for studying the fragmentation behaviour of two classes of CADs, setting m/z 191 as a diagnostic moiety. When it was applied to artichoke sample, ten CADs were detected and elucidated in a single PIS run. Furthermore, method validation was implemented including: specificity (no interference), linearity (≥0.9993), limit of detection (LOD<0.12 ng mL(-1)) and limit of quantification (LOQ<0.25 ng mL(-1)), precision (RSD≤3.6), recovery (91.4-95.9%) and stability (at least 12 h). This approach was proven to be a powerful, selective and sensitive tool for rapid screening and semi-determination of untargeted components in natural products.

  11. Resin-acid derivatives as potent electrostatic openers of voltage-gated K channels and suppressors of neuronal excitability.

    PubMed

    Ottosson, Nina E; Wu, Xiongyu; Nolting, Andreas; Karlsson, Urban; Lund, Per-Eric; Ruda, Katinka; Svensson, Stefan; Konradsson, Peter; Elinder, Fredrik

    2015-08-24

    Voltage-gated ion channels generate cellular excitability, cause diseases when mutated, and act as drug targets in hyperexcitability diseases, such as epilepsy, cardiac arrhythmia and pain. Unfortunately, many patients do not satisfactorily respond to the present-day drugs. We found that the naturally occurring resin acid dehydroabietic acid (DHAA) is a potent opener of a voltage-gated K channel and thereby a potential suppressor of cellular excitability. DHAA acts via a non-traditional mechanism, by electrostatically activating the voltage-sensor domain, rather than directly targeting the ion-conducting pore domain. By systematic iterative modifications of DHAA we synthesized 71 derivatives and found 32 compounds more potent than DHAA. The most potent compound, Compound 77, is 240 times more efficient than DHAA in opening a K channel. This and other potent compounds reduced excitability in dorsal root ganglion neurons, suggesting that resin-acid derivatives can become the first members of a new family of drugs with the potential for treatment of hyperexcitability diseases.

  12. Surface active molecules: preparation and properties of long chain n-acyl-l-alpha-amino-omega-guanidine alkyl acid derivatives.

    PubMed

    Infante, R; Dominguez, J G; Erra, P; Julia, R; Prats, M

    1984-12-01

    Synopsis A new route for the synthesis of long chain N(alpha)-acyl-l-alpha-amino-omega-guamdine alkyl acid derivatives, with cationic or amphoteric character has been established. The general formula of these compounds is shown below. A physico-chemical and antimicrobial s