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排序方式: 共有4135条查询结果,搜索用时 31 毫秒
1.
《Saudi Journal of Biological Sciences》2017,24(6):1249-1254
Coronary Artery Disease (CAD) is a major killer disease throughout the world. Dyslipidemia is a major contributor to the risk of CAD. Several dietary articles traditionally used in India and other South Asian countries reduced dyslipidemia. The present study was undertaken to evaluate the combined effect of Mung bean (Vigna radiata) and Elephant foot yam (Amorphophallus paeoniifolius) on serum lipids and atherogenic indices in albino rats and to compare it with a standard drug Cholestyramine. Thirty healthy albino rats of both sexes (150–200 g) were randomized to 5 groups of 6 animals each. The grouping were done based on the following criteria: Group I: Normal Control Group, Group II: (Standard Group): Cholestyramine resin 5 mg/kg bw, Group III: (Half Dose Group): Drug powder at 540 mg/kg bw, Group IV: (Effective Dose Group): Drug powder at 1080 mg/kg bw, and Group V: (Double Dose Group): Drug powder at 2160 mg/kg bw. Lipid profile was estimated at the beginning and after 30 days of treatment. The Effective and Double doses of the drug reduced Total cholesterol along with levels of Triglycerides, Low density lipoprotein and Very low density lipoprotein levels significantly (p < 0.01) along with a significant (p < 0.01) increase in high density lipoproteins (HDL) in rats. There was also significant (p < 0.01) improvement in atherogenic indices like Castelli Risk Index I, Non HDL C/HDL, Castelli risk Index II, TG/HDL, Atherogenic coefficient and Atherogenic Index of Plasma. The combination of powdered sprouted mung bean and yam powder have excellent lipid lowering potential. 相似文献
2.
Plasma membrane is a multifunctional structure that acts as the initial barrier against infection by intracellular pathogens. The productive HIV-1 infection depends upon the initial interaction of virus and host plasma membrane. Immune cells such as CD4 + T cells and macrophages contain essential cell surface receptors and molecules such as CD4, CXCR4, CCR5 and lipid raft components that facilitate HIV-1 entry. From plasma membrane HIV-1 activates signaling pathways that prepare the grounds for viral replication. Through viral proteins HIV-1 hijacks host plasma membrane receptors such as Fas, TNFRs and DR4/DR5, which results in immune evasion and apoptosis both in infected and uninfected bystander cells. These events are hallmark in HIV-1 pathogenesis that leads towards AIDS. The interplay between HIV-1 and plasma membrane signaling has much to offer in terms of viral fitness and pathogenicity, and a better understanding of this interplay may lead to development of new therapeutic approaches. This article is part of a Special Issue entitled: Viral Membrane Proteins — Channels for Cellular Networking. 相似文献
3.
Stroke is the most common cause of motor disabilities and is a major cause of mortality worldwide. Adult stem cells have been shown to be effective against neuronal degeneration through mechanisms that include both the recovery of neurotransmitter activity and a decrease in apoptosis and oxidative stress. We chose the lineage stroke-prone spontaneously hypertensive rat (SHRSP) as a model for stem cell therapy. SHRSP rats can develop such severe hypertension that they generally suffer a stroke at approximately 1 year of age. The aim of this study was to evaluate whether mesenchymal stem cells (MSCs) decrease apoptotic death and oxidative stress in existing SHRSP brain tissue. The results of qRT-PCR assays showed higher levels of the antiapoptotic Bcl-2 gene in the MSC-treated animals, compared with untreated. Our study also showed that superoxide, apoptotic cells, and by-products of lipid peroxidation decreased in MSC-treated SHRSP to levels similar those found in the animal controls, Wistar Kyoto rats. In addition, we saw a repair of morphological damage at the hippocampal region after MSC transplantation. These data suggest that MSCs have neuroprotective and antioxidant potential in stroke-prone spontaneously hypertensive rats. 相似文献
4.
Trienoic fatty acids, namely -linolenic acid and hexadecatrienoic acid, present in leaf lipids are produced by -3 fatty acid desaturases located in the endoplasmic reticulum and plastid membranes. The changes in the level of trienoic fatty acids during leaf maturation were investigated in wild-type plants of Arabidopsis thaliana (L.) Heynh. and in the fad7 mutant deficient in the activity of a plastid -3 desaturase. The levels of trienoic fatty acids increased in 26 °C- and 15 °C-grown wild-type plants with maturation of leaves. The increase in trienoic fatty acids was mainly due to galactolipids enriched in plastid membranes. In addition, the relative levels of trienoic fatty acids in major glycerolipids, including phospholipids enriched in the endoplasmic reticulum membranes, also increased with leaf maturation. By contrast, when the fad7 mutant was grown at 26 °C, the relative levels of trienoic fatty acids in individual lipids decreased with leaf maturation. The decreases in the levels of trienoic fatty acids, however, were alleviated when the fad7 mutant was grown at 15 °C. These results suggest that the plastid -3 desaturase plays a major role in increasing the levels of trienoic fatty acids with leaf maturation.Abbreviations 163
hexadecatrienoic acid
- 183
-linolenic acid
- DGD
digalactosyldiacylglycerol
- MGD
monogalactosyldiacylglycerol
- PC
phosphatidylcholine
- PE
phosphatidylethanolamine
- TA
trienoic fatty acid
- WT
wild type
- -3
refers to the position of the double bond from the methyl end of a fatty acid
This research was supported in part by Grants-in-Aid for Scientific research (#07251214 and #06804050 to K.I.) from the Ministry of Education, Science and Culture, Japan, and by the research grant from Shorai Foundation. 相似文献
5.
Alessia Antonini Silvia Caioli Luana Saba Giulia Vindigni Silvia Biocca Nadia Canu Cristina Zona 《生物化学与生物物理学报:疾病的分子基础》2018,1864(2):509-519
Amyotrophic Lateral Sclerosis (ALS) is a chronic neurodegenerative disease affecting upper and lower motor neurons, with unknown aetiology. Lipid rafts, cholesterol enriched microdomains of the plasma membrane, have been linked to neurodegenerative disorders like ALS. The NMDA-receptor subcellular localization in lipid rafts is known to play many roles, from modulating memory strength to neurotoxicity. In this study, performed on the widely used G93A mouse model of ALS, we have shown an equal content of total membrane cholesterol in Control and G93A cortical cultures. Moreover, by electrophysiological studies, we have recorded NMDA- and AMPA-evoked currents which were not significantly different between the two neuronal populations. To study the role of membrane cholesterol on glutamate receptor functionality, we have analysed NMDA and AMPA receptors following cholesterol membrane depletion by methyl-β-cyclodextrin (MβCD). Interestingly, MβCD chronic treatment has provoked a significant reduction of NMDA-evoked currents in both cellular populations which was dose- and time-dependent but significantly higher in ALS neurons compared to Control. The different MβCD effect on NMDA-evoked currents was not due to a different membrane receptor subunit composition but seemed to cause in both neuronal populations a NMDA receptor membrane redistribution. MβCD treatment effect was receptor-specific since no alterations in the two neuronal populations were detected on AMPA receptors.These results lead us to speculate for an altered proteomic composition of lipid rafts in cortical mutated neurons and suggest the need for further studies on the lipid rafts composition and on their interaction with membrane receptors in ALS cortices. 相似文献
6.
Himgauri Naik Ted Gauthier Sitanshu Singh Seetharama Jois 《Bioorganic & medicinal chemistry letters》2018,28(22):3506-3513
The human epidermal growth factor receptor (EGFR) family is known to be involved in cell signaling pathways. The extracellular domain of EGFR consists of four domains, of which domain II and domain IV are known to be involved in the dimerization process. Overexpression of these receptors is known to play a significant role in heterodimerization of these receptors leading to the development of cancer. We have designed peptidomimetic molecules to inhibit the EGFR heterodimerization interaction that have shown antiproliferative activity and specificity for HER2-positive cancer cell lines. Among these, a peptidomimetic, compound 5, exhibited antiproliferative activity at low nanomolar concentrations in HER2-overexpressing cancer cell lines. To improve the stability of this peptidomimetic, we have designed and synthesized a novel conjugate of peptidomimetic compound 5 with a lipid, stearic acid. The antiproliferative activity of this conjugate was evaluated in HER2-positive cancer cell lines. Results suggested that the conjugate exhibited selective antiproliferative activity in HER2-overexpressing breast and lung cancer cell lines and was able to block HER2:HER3 heterodimerization. Also, the conjugate showed improved stability with a half-life of 5?h in human serum compared to the half-life of 2?h for parent compound 5. The binding affinity of the conjugate to HER2 protein was evaluated by SPR analysis, and the mode of binding of the lipid conjugate to domain IV of HER2 protein was demonstrated by docking analysis. Thus, this novel lipid conjugate can be used to target HER2-overexpressing cancers. 相似文献
7.
Michael Habeck Haim Haviv Adriana Katz Einat Kapri-Pardes Sophie Ayciriex Andrej Shevchenko Haruo Ogawa Chikashi Toyoshima Steven J. D. Karlish 《The Journal of biological chemistry》2015,290(8):4829-4842
The activity of membrane proteins such as Na,K-ATPase depends strongly on the surrounding lipid environment. Interactions can be annular, depending on the physical properties of the membrane, or specific with lipids bound in pockets between transmembrane domains. This paper describes three specific lipid-protein interactions using purified recombinant Na,K-ATPase. (a) Thermal stability of the Na,K-ATPase depends crucially on a specific interaction with 18:0/18:1 phosphatidylserine (1-stearoyl-2-oleoyl-sn-glycero-3-phospho-l-serine; SOPS) and cholesterol, which strongly amplifies stabilization. We show here that cholesterol associates with SOPS, FXYD1, and the α subunit between trans-membrane segments αTM8 and -10 to stabilize the protein. (b) Polyunsaturated neutral lipids stimulate Na,K-ATPase turnover by >60%. A screen of the lipid specificity showed that 18:0/20:4 and 18:0/22:6 phosphatidylethanolamine (PE) are the optimal phospholipids for this effect. (c) Saturated phosphatidylcholine and sphingomyelin, but not saturated phosphatidylserine or PE, inhibit Na,K-ATPase activity by 70–80%. This effect depends strongly on the presence of cholesterol. Analysis of the Na,K-ATPase activity and E1-E2 conformational transitions reveals the kinetic mechanisms of these effects. Both stimulatory and inhibitory lipids poise the conformational equilibrium toward E2, but their detailed mechanisms of action are different. PE accelerates the rate of E1 → E2P but does not affect E2(2K)ATP → E13NaATP, whereas sphingomyelin inhibits the rate of E2(2K)ATP → E13NaATP, with very little effect on E1 → E2P. We discuss these lipid effects in relation to recent crystal structures of Na,K-ATPase and propose that there are three separate sites for the specific lipid interactions, with potential physiological roles to regulate activity and stability of the pump. 相似文献
8.
Ann M. Dixon Lisa Drake Kelly T. Hughes Elizabeth Sargent Danielle Hunt Jonathan A. Harton James R. Drake 《The Journal of biological chemistry》2014,289(17):11695-11703
Major histocompatibility complex (MHC) class II molecules exhibit conformational heterogeneity, which influences their ability to stimulate CD4 T cells and drive immune responses. Previous studies suggest a role for the transmembrane domain of the class II αβ heterodimer in determining molecular structure and function. Our previous studies identified an MHC class II conformer that is marked by the Ia.2 epitope. These Ia.2+ class II conformers are lipid raft-associated and able to drive both tyrosine kinase signaling and efficient antigen presentation to CD4 T cells. Here, we establish that the Ia.2+ I-Ak conformer is formed early in the class II biosynthetic pathway and that differential pairing of highly conserved transmembrane domain GXXXG dimerization motifs is responsible for formation of Ia.2+
versus Ia.2− I-Ak class II conformers and controlling lipid raft partitioning. These findings provide a molecular explanation for the formation of two distinct MHC class II conformers that differ in their inherent ability to signal and drive robust T cell activation, providing new insight into the role of MHC class II in regulating antigen-presenting cell-T cell interactions critical to the initiation and control of multiple aspects of the immune response. 相似文献
9.
目的:探讨脂代谢紊乱在妊娠期糖尿病(GDM)中的作用,为妊娠期糖尿病的预防及指导临床干预提供理论依据。方法:观察妊娠期糖尿病患者和糖耐量正常孕妇血脂水平及胰岛素抵抗程度差异,分析妊娠期糖尿病患者饮食治疗前后的血脂及炎症标志物的动态变化,于孕12W、24W及36W分别抽取两组孕妇空腹静脉血,测定糖、脂代谢指标及炎症标志物水平,计算血浆致动脉粥样硬化指数(atherogenic index of the plasma,AIP);应用稳态模型胰岛素抵抗指数(HOMA-IR)及胰岛分泌功能指数(HBCI),评价胰岛素抵抗指数(IR)程度及胰岛功能。结果:(1)GDM组的C肽、FINS、HOMA-IR明显高于糖耐量正常组(normal glucose tolerance,NGT)组(p0.05),GDM组HBCI指数低于NGT组(p0.05)。(2)干预组与对照组比较,12W时,TC、TG、HDL、LDL差异均无统计学意义(p0.05);24W及32W差异均有统计学意义(p0.05),均较对照组高。(3)对GDM组中TC、TG、HDL、LDL、AIP、hs-CRP、N及WBC值进行分析,TG、TC、LDL、AIP、hs-CRP、N及WBC值24W较36W及12W高(p0.05);HDL水平24W较36W及12W低(p0.05)。(4)NGT组中TG、TC、LDL、AIP、hs-CRP、N及WBC值36W较24W及12W高(p0.05);HDL水平36W较24W及12W高(p0.05)。结论:GDM孕妇存在着明显的胰岛素抵抗和胰岛β细胞分泌功能受损。GDM孕妇合并较正常妊娠更为严重的炎症反应,血脂水平明显升高,饮食治疗后对改善IR有益,提示在妊娠期糖尿病患者中,通过适当的饮食治疗进而对血糖及血脂的调整可以显著减少母儿并发症。 相似文献
10.
B. Lubec K. R. Herkner H. Brückner H. Höger J. Gialamas D. Adamiker G. Lubec 《Amino acids》1991,1(2):289-292
Summary A series of alpha-alkyl-amino acids were tested for some biological functions in the mouse (OF-1 Himberg) by adding them to the animal chow (30 mg/kg/day) for a period of six weeks. No differences in fluid or food uptake could be observed during the feeding period, as compared to a control group. Histology of liver and kidney did not show any changes. Testing routine clinical chemical parameters (serum substrates and enzymes) revealed the following changes: Hex-Ala and But-Abu increased the serum glucose levels. But-Abu dramatically lowered the triglycerides. Serum albumin was increased by Pent-Ala, Me-Val, and But-Abu. LDH was inhibited by But-Abu. 相似文献