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1.
Chloroquine (CQ) is an antimalaria drug that has been widely used for decades. However, CQ-induced pruritus remains one of the major obstacles in CQ treatment for uncomplicated malaria. Recent studies have revealed that MrgprX1 plays an essential role in CQ-induced itch. To date, a few MrgprX1 antagonists have been discovered, but they are clinically unavailable or lack selectivity. Here, a cell-based high-throughput screening was performed to identify novel antagonists of MrgprX1, and the screening of 2543 compounds revealed two novel MrgprX1 inhibitors, berbamine and closantel. Notably, berbamine potently inhibited CQ-mediated MrgprX1 activation (IC50 = 1.6 μM) but did not alter the activity of other pruritogenic GPCRs. In addition, berbamine suppressed the CQ-mediated phosphorylation of ERK1/2. Interestingly, CQ-induced pruritus was significantly reduced by berbamine in a dose-dependent manner, but berbamine had no effect on histamine-induced, protease-activated receptors 2-activating peptide-induced, and deoxycholic acid-induced itch in mice. These results suggest that berbamine is a novel, potent, and selective antagonist of MrgprX1 and may be a potential drug candidate for the development of therapeutic agents to treat CQ-induced pruritus.  相似文献   

2.
The 2019 novel coronavirus, known as severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) or coronavirus disease 2019 (COVID-19), is causing a global pandemic. The virus primarily affects the upper and lower respiratory tracts and raises the risk of a variety of non-pulmonary consequences, the most severe and possibly fatal of which are cardiovascular problems. Data show that almost one-third of the patients with a moderate or severe form of COVID-19 had preexisting cardiovascular comorbidities such as diabetes mellitus, obesity, hypertension, heart failure, or coronary artery disease. SARS-CoV2 causes hyper inflammation, hypoxia, apoptosis, and a renin–angiotensin system imbalance in a variety of cell types, primarily endothelial cells. Profound endothelial dysfunction associated with COVID-19 can be the cause of impaired organ perfusion that may generate acute myocardial injury, renal failure, and a procoagulant state resulting in thromboembolic events. We discuss the most recent results on the involvement of endothelial dysfunction in the pathogenesis of COVID-19 in patients with cardiometabolic diseases in this review. We also provide insights on treatments that may reduce the severity of this viral infection.  相似文献   

3.
A small molecule, perylene bisimide imidazolyl derivative (PBI‐ID), has been identified and developed as a specific marker for labelling multifunctional fat bodies in various organisms, including Drosophila and mammalian adipocytes. Interestingly, PBI‐ID neither labels the plasma membranes nor cell nuclei by trapping into it. A remarkable feature of unbound PBI‐ID is diminished fluorescence, which reduces the background emission noise, while contrasting the bound state effectively.  相似文献   

4.
Hydroxy lipids (L-OH) and 4-hydroxy-2-hexenal (HHE) levels as well as other parameters such as lipid level, lipid class, fatty acid composition, and other aldehydes levels in the liver of diseased fish were investigated. Although significant differences in lipid level, lipid class, fatty acid composition, and other aldehyde levels were not always observed between normal and diseased fish, L-OH and HHE levels were significantly higher in the liver of the diseased fish than in that of the normal fish cultured with the same feeds under the same conditions. In the liver of puffer fish (Fugu rubripes) infected with Trichodina, L-OH and HHE levels significantly increased from 25.29 ± 5.04 to 47.70 ± 5.27 nmol/mg lipid and from 299.79 ± 25.25 to 1,184.40 ± 60.27 nmol/g tissue, respectively. When the levels of HHE and other aldehydes in the liver of the normal and diseased puffer fish were plotted, a linear relationship with a high correlation coefficient was observed between HHE and propanal (r 2 = 0.9447). Increased L-OH and HHE levels in the liver of the diseased fish and a high correlation between HHE and propanal in the liver of the normal and diseased fish were also observed in flat fish (Paralichthys olivaceus) infected with streptococcus, yellowtail (Seriola quinqueradiata) infected with jaundice, and amberjack (S. purpurascens) infected with Photobacterium damselae subsp. piscicida.  相似文献   

5.
Storage lipids, triacylglycerols (TAG), and steryl esters (SE), are predominant constituents of lipid droplets (LD) in fungi. In several yeast species, metabolism of TAG and SE is linked to various cellular processes, including cell division, sporulation, apoptosis, response to stress, and lipotoxicity. In addition, TAG are an important source for the generation of value-added lipids for industrial and biomedical applications. The fission yeast Schizosaccharomyces pombe is a widely used unicellular eukaryotic model organism. It is a powerful tractable system used to study various aspects of eukaryotic cellular and molecular biology. However, the knowledge of S. pombe neutral lipids metabolism is quite limited. In this review, we summarize and discuss the current knowledge of the homeostasis of storage lipids and of the role of LD in the fission yeast S. pombe with the aim to stimulate research of lipid metabolism and its connection with other essential cellular processes. We also discuss the advantages and disadvantages of fission yeast in lipid biotechnology and recent achievements in the use of S. pombe in the biotechnological production of valuable lipid compounds.  相似文献   

6.
The olive fruit is essentially constituted by the epicarp, or skin, mesocarp, or pulp, and the endocarp, or stone, and the latter includes the seed. Table olives (also called eating olives) are prepared from healthy, specifically cultivated, olive varieties picked at the right maturation stage and whose quality, after appropriate processing, corresponds to that of an edible well preserved product. The most important industrial preparations of table olives are the Spanish (or Sevillian) for green olives, the Californian for oxidised black olives, and the Greek for naturally black olives. In the Spanish and Californian procedures, olives are treated with a diluted aqueous NaOH solution, that brings about several changes in the susceptible classes of compounds in the fruit. Note, however, that the composition of the triglycerides remain unaffected by these procedures. After the treatment the olives are rinsed to remove the alkali, and the fruit is then left to ferment in brine for several months. The production of naturally black olives in brine, according to the Greek traditional method, is a simple, natural process which does not use chemicals. The main phenols in the olive are oleuropein, hydroxytyrosol (β(3‐4‐dihydroxyphenyl)ethanol), tyrosol (β(4‐hydroxyphenyl) ethanol) and verbascoside; the major polycyclic triterpenes are the oleanolic and maslinic acids. The NaOH treatment hydrolysed oleuropein into β(3‐4‐dihydroxyphenyl) ethanol, oleoside 11‐methylester and oleoside. These last glucosides and the oleuropein itself, in acidic medium, yielded glucose and a number of compounds called, collectively, oleuropein aglycones. During the fermentation process phenols diffuse from the pulp into the brine. Also, even during the alkaline treatment, there is the rapid diffusion of the pentacyclic oleanolic and maslinic acids salts into the brine.  相似文献   

7.
白果中总黄酮的含量及其油脂的化学成分研究   总被引:3,自引:0,他引:3  
对泰兴地区不同品种白果中油脂及总黄酮的含量进行分析。结果表明:东台果中油脂的含量高达7.58%,其次是大佛子和蝙蝠子,两者皆为4.32%。油脂脂肪酸中含有65%以上不饱和油酸和亚油酸,其中棕榈油酸2.342%;棕榈酸7.915%; 7,10-C18:2亚油酸2.446%;8,11-C18:2亚油酸31.136%;油酸(9,11-C18:1)32.873%;硬脂酸1.589%。同时筛选出总黄酮含量高的品种,其中大佛子与蝙蝠子总黄酮的含量分别为0.150%、0.127%。因此,白果具有很好的药食开发应用前景。  相似文献   

8.
According to the World Health Organization, cardiovascular diseases are the main cause of death worldwide. They may be caused by various factors or combinations of factors. Frequently, endothelial dysfunction is involved in either development of the disorder or results from it. On the other hand, the endothelium may be disordered for other reasons, e.g., due to infection, such as COVID-19. The understanding of the role and significance of the endothelium in the body has changed significantly over time—from a simple physical barrier to a complex system encompassing local and systemic regulation of numerous processes in the body. Endothelium disorders may arise from impairment of one or more signaling pathways affecting dilator or constrictor activity, including nitric oxide–cyclic guanosine monophosphate activation, prostacyclin–cyclic adenosine monophosphate activation, phosphodiesterase inhibition, and potassium channel activation or intracellular calcium level inhibition. In this review, plants are summarized as sources of biologically active substances affecting the endothelium. This paper compares individual substances and mechanisms that are known to affect the endothelium, and which subsequently may cause the development of cardiovascular disorders.  相似文献   

9.
Many cellular processes are controlled by small GTPases, which can be activated by guanine nucleotide exchange factors (GEFs). The RhoGEF Trio contains two GEF domains that differentially activate the small GTPases such as Rac1/RhoG and RhoA. These small RhoGTPases are mainly involved in the remodeling of the actin cytoskeleton. In the endothelium, they regulate junctional stabilization and play a crucial role in angiogenesis and endothelial barrier integrity. Multiple extracellular signals originating from different vascular processes can influence the activity of Trio and thereby the regulation of the forementioned small GTPases and actin cytoskeleton. This review elucidates how various signals regulate Trio in a distinct manner, resulting in different functional outcomes that are crucial for endothelial cell function in response to inflammation.  相似文献   

10.
The endothelium has a fundamental role in the cardiovascular complications of coronavirus disease 2019 (COVID-19). Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) particularly affects endothelial cells. The virus binds to the angiotensin-converting enzyme 2 (ACE-2) receptor (present on type 2 alveolar cells, bronchial epithelial cells, and endothelial cells), and induces a cytokine storm. The cytokines tumor necrosis factor alpha, interleukin-1 beta, and interleukin-6 have particular effects on endothelial cells—leading to endothelial dysfunction, endothelial cell death, changes in tight junctions, and vascular hyperpermeability. Under normal conditions, apoptotic endothelial cells are removed into the bloodstream. During COVID-19, however, endothelial cells are detached more rapidly, and do not regenerate as effectively as usual. The loss of the endothelium on the luminal surface abolishes all of the vascular responses mediated by the endothelium and nitric oxide production in particular, which results in greater contractility. Moreover, circulating endothelial cells infected with SARS-CoV-2 act as vectors for viral dissemination by forming clusters that migrate into the circulation and reach distant organs. The cell clusters and the endothelial dysfunction might contribute to the various thromboembolic pathologies observed in COVID-19 by inducing the formation of intravascular microthrombi, as well as by triggering disseminated intravascular coagulation. Here, we review the contributions of endotheliopathy and endothelial-cell-derived extracellular vesicles to the pathogenesis of COVID-19, and discuss therapeutic strategies that target the endothelium in patients with COVID-19.  相似文献   

11.
Early endosomes are dynamic intracellular compartments that fuse with incoming endocytic carrier vesicles and associated cargoes from the plasma membrane. It has been long known that the chemical structures of lipids confer striking properties and rich biochemistry on bilayers. Although the organisational principles of the plasma membrane are relatively better understood, understanding endosomal membranes has been challenging. It has become increasingly apparent that endosomal membranes, because of their lipid compositions and interactions, use distinct lipid chemistries. We discuss the biochemical and biophysical phenomena in play at the early endosomal membrane. We focus on cholesterol, phosphoinositides, and phosphatidylserine and their clear roles in endosome functions. We discuss the various principles and mechanisms underpinning how these lipids are implicated at the functional level in the working of endosomes, and we summarise early endosomes as a multimodal organelle employing distinct lipid‐specific mechanisms.  相似文献   

12.
The ability to cope with and adapt to changes in the environment is essential for all organisms. Osmotic pressure is a universal threat when environmental changes result in an imbalance of osmolytes inside and outside the cell which causes a deviation from the normal turgor. Cells have developed a potent system to deal with this stress in the form of mechanosensitive ion channels. Channel opening releases solutes from the cell and relieves the stress immediately. In bacteria, these channels directly sense the increased membrane tension caused by the enhanced turgor levels upon hypoosmotic shock. The mechanosensitive channel of small conductance, MscS, from Escherichia coli is one of the most extensively studied examples of mechanically stimulated channels. Different conformational states of this channel were obtained in various detergents and membrane mimetics, highlighting an intimate connection between the channel and its lipidic environment. Associated lipids occupy distinct locations and determine the conformational states of MscS. Not all these features are preserved in the larger MscS-like homologues. Recent structures of homologues from bacteria and plants identify common features and differences. This review discusses the current structural and functional models for MscS opening, as well as the influence of certain membrane characteristics on gating.  相似文献   

13.
This study examined the dietary effects of enzymatically modified sesame oil with caprylic acid (structured lipids, SL) and phytosteryl esters (PE) on blood lipid profiles and cardiovascular parameters of spontaneously hypertensive rats (SHR) fed high-fat and high-cholesterol (HFHC) diets. The dietary groups were: normal diet (control), sesame oil (SO), SL, SO fortified with PE (SOP), and SL fortified with PE (SLP). After 9 weeks of feeding, the body weights, liver weights, and liver weight/body weight ratios in all HFHC-fed groups were higher than controls. Plasma total and LDL cholesterol levels in all HFHC-fed groups were similar to one another but higher than those in controls. Plasma HDL cholesterol levels in rats fed SOP and SLP were higher than those in controls or rats fed SO and SL. Plasma HDL/total cholesterol ratios in rats fed SOP and SLP were similar to those in controls and were higher than those in rats fed SO and SL. There was no difference in plasma lipid profiles between rats fed SO and SL. Arterial blood pressures (BP) in conscious HFHC-fed rats were similar to those in controls whereas heart rates (HR) in all HFHC-fed groups were similar to one another but were higher than that in controls. These findings demonstrate that (1) the dietary effects of SL on plasma lipid profiles and resting BP and HR are similar to those of SO, (2) PE had positive effects on plasma lipid profiles, and (3) 9-week intake of SL and PE did not have pronounced effects on resting BP but induced tachycardia in SHR.  相似文献   

14.
Since first being reported in 2006, the DNA origami approach has attracted increasing attention due to programmable shapes, structural stability, biocompatibility, and fantastic addressability. Herein, we provide an account of recent developments of DNA origami as scaffolds for templating the selfassembly of distinct biocomponents, essentially proteins and lipids, into a diverse spectrum of integrated supramolecular architectures. First, the historical development of the DNA origami concept is briefly reviewed. Next, various applications of DNA origami constructs in controllable directed assembly of soluble proteins are discussed. The manipulation and self-assembly of lipid membranes and membrane proteins by using DNA origami as scaffolds are also addressed. Furthermore, recent progress in applying DNA origami in cryoelectron microscopy analysis is discussed. These advances collectively emphasize that the DNA origami approach is a highly versatile, fast evolving tool that may be integrated with lipids and proteins in a way that meets future challenges in molecular biology and nanomedicine.  相似文献   

15.
Two double chain cationic lipids QAS C n -2-S (n = 12, 14) derived from thio galactose and carbamate-linkage tertiary amine were synthesized and their structures were confirmed by MS, TOF-MS, 1H NMR and 13C NMR. The QAS C12-2-S revealed superior surface activity compared with QAS C14-2-S with lower CMC and γCMC. Though Lipo C12-2-S displayed large average particle-size with high polydispersity, positive charged Lipo C n -2-S can be combined with the negative charged DNA, also negatively stained TEM images confirmed the formation of vesicles. All the above prove that the Lipo C n -2-S is helpful for gene transfection.  相似文献   

16.
In this study, fatty acid analysis and lipid nutrition assessment of five common cod products from fishery markets are performed by gas chromatography (GC). Meanwhile, a lipid‐based rapid identification method for cod products using thin‐layer chromatography (TLC) is established. GC analysis showed that 13, 11, 13, 13, and 6 types of fatty acids are identified in Atlantic cod, Pacific cod, sablefish, silver cod, and oilfish, respectively. The nutrition assessment shows that Atlantic cod, Pacific cod, sablefish, and silver cod have healthier atherogenicity index (AI) and thrombogenic index (TI), suggesting these four types of fish have higher nutritive value. In terms of the fatty acid, the five species of fish can be classified by systematic clustering and heat map analysis. The TLC‐rapid lipid identification method shows that sablefish and silver cod contain characteristic triglyceride, and oilfish contains characteristic wax ester, which are obviously different from the Atlantic cod and the Pacific cod. The oilfish could be distinguished from the high nutritive value of sablefish, silver cod, Atlantic cod, and Pacific cod by the rapid identification method in a few minutes. This study provides important nutritional information and a method for rapid identification of cod products.  相似文献   

17.
Although widely occurring lipid oxidation, which is triggered by reactive oxygen species (ROS), produces a variety of oxidized lipids, practical methods to efficiently analyze oxidized lipids remain elusive. Herein, it is shown that the glycoblotting platform can be used to analyze oxidized lipids. Analysis is based on the principle that lipid aldehydes, one of the oxidized lipid species, can be captured selectively, enriched, and detected. Moreover, 3‐methyl‐1‐p‐tolyltriazene (MTT) methylates phosphoric and carboxylic acids, and this MTT‐mediated methylation is, in combination with conventional tandem mass spectrometry (MS/MS) analysis, an effective method for the structural analysis of oxidized lipids. By using three classes of standards, liposomes, and a lipoprotein, it is demonstrated that glycoblotting represents a powerful approach for focused lipidomics, even in complex macromolecules.  相似文献   

18.
微拟球藻油脂萃取及脱脂藻水热液化   总被引:1,自引:0,他引:1  
唐晓寒  杨晓奕 《化工学报》2019,70(11):4356-4362
为提高微藻的综合利用效率,使用不同的溶剂系统分别对干、湿微拟球藻进行油脂萃取,并对脱脂后的藻渣进行水热液化实验,探究溶剂萃取脱脂对微藻水热液化产物的影响。溶剂萃取的结果表明,极性溶剂对油脂的萃取率达到25.0%,但对脂质的萃取缺乏选择,萃取物的脂肪酸甲酯产率仅为29.68%;混合溶剂萃取的脂肪酸甲酯回收率达到57.70%。脱脂后的微拟球藻水热粗油产率为27.7%~34.6%,氮含量为5.29%~6.68%,主要由脂肪酸、脂肪酸酯、脂肪酸酰胺、长链烃类、胺类、含氧化合物和含氮杂环化合物组成。经甲醇萃取后的湿藻水热粗油产率为34.6%,氮含量为5.44%,过程能耗低,表明甲醇萃取湿藻结合水热液化具有一定的应用前景。  相似文献   

19.
Chopra R  Sambaiah K 《Lipids》2009,44(1):37-46
Lipase-catalyzed interesterification was used to prepare different structured lipids (SL) from rice bran oil (RBO) by replacing some of the fatty acids with α-linolenic acid (ALA) from linseed oil (LSO) and n-3 long chain polyunsaturated fatty acids (PUFA) from cod liver oil (CLO). In one SL, the ALA content was 20% whereas in another the long chain n-3 PUFA content was 10%. Most of the n-3 PUFA were incorporated into the sn-1 and sn-3 positions of triacylglycerol. The influence of SL with RBO rich in ALA and EPA + DHA was studied on various lipid parameters in experimental animals. Rats fed RBO showed a decrease in total serum cholesterol by 10% when compared to groundnut oil (GNO). Similarly structured lipids with CLO and LSO significantly decreased total serum cholesterol by 19 and 22% respectively compared to rice bran oil. The serum TAGs level of rats fed SLs and blended oils were also significantly decreased by 14 and 17% respectively compared to RBO. Feeding of an n-3 PUFA rich diet resulted in the accumulation of long chain n-3 PUFA in various tissues and a reduction in the long chain n-6 PUFA. These studies indicate that the incorporation of ALA and EPA + DHA into RBO can offer health benefits.  相似文献   

20.
Bixa orellana L. seeds possess a resinous lipid (6.3 %), which has a pungent and spicy odour. The seed is known for its medicinal properties such as anti‐inflammatory, antipyretic activity and as a cure for tonsilitis. Trachyspermum copticum L. seed is a well known digestive aid and relief from colic pain. T. copticum possesses essential oil rich in thymol (>50 %) and lipid (15.6 %). The present study was aimed to quantify lipid classes of these two species by silicic acid chromatography and analyze their fatty acid composition by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). It was observed that the seed lipids are rich in neutral lipids with 98.1 and 95.2 % and lower quantities of glycolipids of 1.5 and 3.8 % and phospholipids of 0.36 and 1.0 % in B. orellana and T. copticum, respectively. The fatty acid composition of B. orellana seed lipid showed major quantities of palmitic (26.9 %), linoleic (26.1 %), oleic (17.5 %), linolenic (15.1 %), stearic acid (10.8 %) and small quantities of eicosanoic acid (3.6 %). In T. copticum seed lipids, petroselinic acid (68.3 %) and linoleic acid (25.3 %) together constituted 93 % of the total lipid. The results revealed that the lipids after recovery of the essential components namely, bixin and volatile oil from B. orellana and T. copticum, respectively can be further explored for industrial applications.  相似文献   

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