Protective effect of long-chain polyunsaturated fatty acids on hepatorenal syndrome in rats

BACKGROUND Hepatorenal syndrome(HRS)is the most prevalent form of acute kidney injury in cirrhotic patients.It is characterized by reduced renal blood flow and represents the most severe complication in cirrhotic patients with advanced disease.Previous research has indicated that antioxidants can delay the onset of a hyperdynamic circulatory state in cirrhosis and improve renal function in HRS patients.Regular omega-3 supplementation has significantly reduced the risk of liver disease.This supplementation could represent an additional therapy for individuals with HRS.AIM To evaluated the antioxidant effect of omega-3 polyunsaturated fatty acid supplementation on the kidneys of cirrhotic rats.METHODS Secondary biliary cirrhosis was induced in rats by biliary duct ligation(BDL)for 28 d.We used 24 male Wistar rats divided into the following groups:I(control);II(treated with omega-3,1 g/kg of body weight);III(BDL treated with omega-3,1 g/kg of body weight);and IV(BDL without treatment).The animals were killed by overdose of anesthetic;the kidneys were dissected,removed,frozen in liquid nitrogen,and stored in a freezer at-80℃for later analysis.We evaluated oxidative stress,nitric oxide(NO)metabolites,DNA damage by the comet assay,cell viability test,and apoptosis in the kidneys.Data were analyzed by one-way analysis of variance,and means were compared using the Tukey test,with P≤0.05.RESULTS Omega-3 significantly decreased the production of reactive oxygen species(P<0.001)and lipoperoxidation in the kidneys of cirrhotic rats treated with omega-3(P<0.001).The activity of the antioxidant enzymes superoxide dismutase and catalase increased in the BDL+omega-3 group compared to the BDL group(P<0.01).NO production,DNA damage,and caspase-9 cleavage decreased significantly in the omega-3-treated BDL group.There was an increase in mitochondrial electrochemical potential(P<0.001)in BDL treated with omega-3 compared to BDL.No changes in the cell survival index in HRS with omega-3 compared to the control group(P>0.05)were observed.CONCLUSION The study demonstrates that omega-3 can protect cellular integrity and function by increasing antioxidant enzymes,inhibiting the formation of free radicals,and reducing apoptosis.

Surplus dietary isoleucine intake enhanced monounsaturated fatty acid synthesis and fat accumulation in skeletal muscle of finishing pigs

Background: Isoleucine(Ile) has been implicated in the regulation of energy homeostasis and adipogenesis.However,the impact of surplus dietary Ile intake on muscle lipogenesis remains unknown.The present study aimed to investigate the impact of dietary supplementation of extra-Ile on lipogenesis,fatty acid profile and lipid accumulation in skeletal muscle in finishing pigs.Methods: Forty-eight barrows with initial body weight of 77.0 ± 0.1 kg were allotted to one of two groups and fed diets containing 0.39%,0.53% standardized ileal digestible(SID) Ile with six replicates per treatment and four pigs per replicate for 30 d.Results: Dietary Ile intake significantly improved the intramuscular fat(IMF) content and monounsaturated fatty acid(MUFA) concentration in the skeletal muscle(P < 0.05),and decreased the drip loss and shear force(P < 0.05) without influencing the growth performance of pigs(P > 0.05).Moreover,the phosphorylation of adenosine monophosphate activated protein kinase α(AMPKα) and acetyl coenzyme A carboxylase(ACC) proteins that monitor lipid metabolism were decreased in skeletal muscle of pigs offered extra-Ile diet(P < 0.05).The mRNA expression of adipose-specific genes adipocyte determination and differentiation factor 1(ADD1),fatty acid synthase(FAS),and stearoyl-CoA desaturase(SCD) were upregulated and the activity of SCD was increased as well(P < 0.05).Conclusions: Surplus dietary Ile intake could increase IMF accumulation and MUFA synthesis in skeletal muscle through depressing the phosphorylation of AMPKα-ACC and stimulating the expression and activity of SCD,and increasing the capability of lipogenesis in skeletal muscle.

Long-chain acyl-CoA synthetase in fatty acid metabolism involved in liver and other diseases:An update

Long-chain acyl-Co A synthetase(ACSL) family members include five different ACSL isoforms, each encoded by a separate gene and have multiple spliced variants. ACSLs on endoplasmic reticulum and mitochondrial outer membrance catalyze fatty acids with chain lengths from 12 to 20 carbon atoms to form acyl-Co As, which are lipid metabolic intermediates and involved in fatty acid metabolism, membrane modifications and various physiological processes. Gain- or lossof-function studies have shown that the expression of individual ACSL isoforms can alter the distribution and amount of intracellular fatty acids. Changes in the types and amounts of fatty acids, in turn, can alter the expression of intracellular ACSLs. ACSL family members affect not only the proliferation of normal cells, but the proliferation of malignant tumor cells. They also regulate cell apoptosis through different signaling pathways and molecular mechanisms. ACSL members have individual functions in fatty acid metabolism in different types of cells depending on substrate preferences, subcellular location and tissue specificity, thus contributing to liver diseases and metabolic diseases, such as fatty liver disease, obesity, atherosclerosis and diabetes. They are also linked to neurological disorders and other diseases. However, the mechanisms are unclear. This review addresses new findings in the classification and properties of ACSLs and the fatty acid metabolismassociated effects of ACSLs in diseases.

Impacts of the unsaturation degree of long-chain fatty acids on the volatile fatty acid profiles of rumen microbial fermentation in goats in vitro

This study investigated the impacts of the degree of unsaturation （unsaturity） of long-chain fatty acids on volatile fatty acid （VFA） profiles of rumen fermentation in vitro. Six types of long-chain fatty acids, including stearic acid （C18：0, control group）, oleic acid （C18：1, n-9）, linoleic acid （C18：2, n-6）, a-linolenic acid （C18：3, n-3）, arachidonic acid （C20：4, n-6） and eicosapentaenoic acid （C20：5, n-3）, were tested. Rumen fluid from three goats fitted with ruminal fistulae was used as inoculum and the inclusion rate of long-chain fatty acid was at 3% （w/w） of substrate. Samples were taken for VFA analysis at 0, 3, 6, 9, 12, 18 and 24 h of incubation, respectively. The analysis showed that there were significant differences in the total VFA among treatments, sampling time points, and treatment×time point interactions （P〈0.01）. a-Linolenic acid had the highest total VFA （P〈0.01） among different long-chain fatty acids tested. The molar proportion of acetate in total VFA significantly differed among treatments （P〈0.01） and sampling time points （P〈0.01）, but not treatment×time point interactions （P〉0.05）. In contrast, the molar proportion of propionate did not differ among treatments during the whole incubation （P〉0.05）. However, for butyrate molar proportions, significant differences were found not only among sampling time points but also among treatments and treatment×time point interactions （P〈0.01）, with eicosapentaenoic acid having the highest value （P〈0.01）. Additionally, no statistically significant differences were found in the acetate to propionate ratios among treatments groups （P〉0.05）, even the treatments stearic acid and a-linolenic acid were numerically higher than the others. The inclusion of 3% long-chain unsaturated fatty acids differing in the degree of unsaturation brought out a significant quadratic regression relation between the total VFA concentration and the double bond number of fatty acid. In conclusion, the a-linolenic acid with 3 double bonds appeared better for improving rumen microbial fermentation and the total VFA concentration.

Effects of long-chain fatty acid supplementation on the growth performance of grower and finisher pigs: a meta-analysis

Background: Supplementation of feed with long-chain fatty acids(LCFAs) during the grower and finisher phases has long been discussed as a growth promotion strategy in pigs, but its effects are inconsistent. The purpose of our study was to comprehensively evaluate its effects on the growth performance based on the average daily gain(ADG), average daily feed intake(ADFI) and gain: feed(G:F) ratio and to unveil the roles of the basal diet, LCFA concentration and LCFA saturation.Results: We searched the Pub Med and Web of Science databases(articles published from Jan 1 st, 2000, to Sep 30 th,2018;restricted to English) and compared LCFA-supplemented diets with control diets. We retrieved 2346 studies, 18 of which(1314 pigs, 26 records) were eligible for our analysis. We used a random-effects model to calculate the weighted mean differences(WMDs) and 95% confidence intervals(CIs). LCFA supplementation in the grower-finisher phase improved the ADG(WMD = 41.74 g/d, 95% CI: 8.81 to 74.66, P = 0.013) and G:F ratio(WMD = 0.019, 95% CI: 0.006 to 0.032, P = 0.003). For supplementation solely in the finisher phase, we found a similar performance in the ADG(WMD = 39.93 g/d, 95% CI: 26.48 to 53.38, P < 0.001) and G:F ratio(WMD = 0.019, 95% CI: 0.006 to 0.032, P < 0.001) but a reduction in the ADFI(WMD =-83.863 g/d, 95% CI:-156.157 to-11.569, P = 0.023). Specifically, approximately 5%LCFA supplementation in the finisher phase had significant effects on the ADG(WMD = 51.385 g/d, 95% CI: 35.816 to66.954, P < 0.001), ADFI(WMD =-102.869 g/d, 95% CI:-189.236 to-16.502, P = 0.02) and G:F ratio(WMD = 0.028, 95%CI: 0.018 to 0.039, P < 0.001), whereas a concentration of approximately 1% exhibited no effects.Conclusions: Overall, regardless of the basal diet and saturation, LCFA supplementation greatly improves the growth performance of grower and finisher pigs, primarily by increasing the energy density.

Identification of a Long-Chain Fatty Acid Elongase from Nannochloropsis sp. Involved in the Biosynthesis of Fatty Acids by Heterologous Expression in Saccharomyces cerevisiae

The marine microalga Nannochloropsis sp.contains various elongases and desaturases that are critical for biosynthesis of polyunsaturated fatty acids.A full-length cDNA encoding a long-chain fatty acid elongase,named Ns FAE,was cloned from Nannochloropsis sp..The open reading frame of Ns FAE(GenBank accession no.MF680548)consisted of 1068 bp and encoded a predicted protein of 355 amino acids with molecular mass 38.8 k Da.The deduced polypeptide showed 43%–44%identity to fatty acyl elongases from other algae.RT-PCR experiments indicated that the Ns FAE gene exhibited the highest expression in Nannochloropsis sp.at 72 h(i.e.,during the third growth stage)and the expression was significantly lower in the other four growth stages.Plasmid p Ns FAE-CRISPR and a recombinant DNA fragment(ADH1p-Ns FAE-CYCt)were transformed into Saccharomyces cerevisiae strain BY4742 using the CRISPR-Cas system.Yeast transformants containing Ns FAE produced three fatty acids not normally present in wild-type BY4742-linoleic acid,linolenic acid and eicosadienoic acid-indicating that Ns FAE encodes a functional elongase enzyme.

The effects of the unsaturated degree of long-chain fatty acids on the rumen microbial protein content and the activities of transaminases and dehydrogenase in vitro

This study investigated the effects of the degree of unsaturation（unsaturity） of long-chain fatty acids on microbial protein content and the activities of transaminases and dehydrogenase in vitro using goat rumen fluid as the cultural medium.Six types of fatty acids,stearic acid（C18：0,group A,control group）,oleic acid（C18：1,n-9,group B）,linoleic acid（C18：2,n-6,group C）,α-linolenic acid（C18：3,n-3,group D）,arachidonic acid（C20：4,n-6,group E）,and eicosapentaenoic acid（C20：5,n-3,group F）,were tested,and the inclusion ratio of each fatty acid was 3%（w/w） in total of culture substrate.Samples were taken at 0,3,6,9,12,18 and 24 h,respectively,during culture for analyses.Compared with stearic acid,linoleic acid,a-linolenic acid,and arachidonic acid increased the bacterial protein content,while oleic acid and eicosapentaenoic acid had no significant effects;the protozoal protein content was reduced for all the unsaturated fatty acids,and the magnitude of the reduction appeared to be associated with the degree of unsaturity of fatty acids.The total microbial protein content was dominantly accounted by the protozoal protein content（about 4-9 folds of the bacterial protein）,and only increased by linoleic acid,but reduced by oleic acid,arachidonic acid and eicosapentaenoic acid.There were no significant effects in the activities of both glutamic oxaloacetic transaminase（GOT） and glutamic-pyruvic transaminase（GPT） for all the other fatty acids,except for arachidonic acid which enhanced GOT activity and oleic acid which enhanced GPT activity.The total dehydrogenase activity was positively correlated with the degree of unsaturation of fatty acids.In conclusion,the inclusion of 3%of long-chain unsaturated fatty acids increased bacterial protein content,whereas reduced protozoal protein content and enhanced dehydrogenase activity.The fatty acids with more than three double bonds had detrimental effects on the microbial protein content.This work demonstrates for the first time the effect rule of the unsaturation degree of long-chain fatty acids on the rumen microbial protein in vitro.

Roles of Long-chain Acyl Coenzyme A Synthetase in Absorption and Transport of Fatty Acid

Long-chain acyl coenzyme A synthetase(ACSL) is a member of the synthetase family encoded by a multigene family;it plays an important role in the absorption and transport of fatty acid.Here we review the roles of ACSL in the regulating absorption and transport of fatty acid,as well as the connection between ACSL and some metabolic diseases.

Study on Extracting Rare Earth from Sulfate System by Long-Chain Fatty Acid

The extraction of rare earths by long-chain fatty acid in kerosene from sulphate system was described.It was demonstrated from the experimental results that the ratio of kerosene: fatty acid: isooctanol = 55 : 30: 15 ( V/V),By the saturation capability method and the slope method, the extracted reaction mechanism of the extraction of rare earth was studied.It is shown that the extraction reaction conform to the cation exchange reaction mechanism.The extracted sequence of rare earth was determined in this system and it is shown that there is no tetrad effect and the position of yttrium is between lanthanum and cerium.

Natural long-chain saturated fatty acids doped LNPs enabling spleen selective mRNA translation and potent cancer immunotherapy

Rationally tailored lipid nanoparticles(LNPs)with efficient and tunable delivery of mRNA in vivo are crucial for mRNA vaccines.Selective expression of antigenic protein in lymphoid tissues/organs could improve the immunostimulatory efficacy and safety of LNPs-based mRNA vaccines.Inspired by the metabolic behavior that long-chain saturated fatty acids tending to enter lymphoid tissue rather than the liver,we developed fatty acid-doped LNPs capable of mediating differential protein expressions in the liver and spleen when administered intravenously.When the molar ratio of saturated fatty acid located 60%–70%,the doped LNPs achieved the spleen selective mRNA translation.The mechanism could be attributed to the different cellular uptake behaviors of saturated fatty acids in hepatocytes.Immunization with a model antigen(ovalbumin)mRNA-loaded spleen selective LNPs,we observed enhanced antigen-specific T cell immune responses,and potent immunotherapeutic and immunoprophylactic efficacy in the mouse lymphoma model.Our natural long-chain saturated fatty acids metabolic characteristics-inspired design of LNPs for spleen-selective mRNA vaccines delivery will provide references for designing mRNA vaccines with high efficacy and safety for tumor immunotherapy.

Fatty acid metabolism and acyl-CoA synthetases in the liver-gut axis

Fatty acids are energy substrates and cell components which participate in regulating signal transduction,transcription factor activity and secretion of bioactive lipid mediators.The acyl-CoA synthetases(ACSs)family containing 26 family members exhibits tissue-specific distribution,distinct fatty acid substrate preferences and diverse biological functions.Increasing evidence indicates that dysregulation of fatty acid metabolism in the liver-gut axis,designated as the bidirectional relationship between the gut,microbiome and liver,is closely associated with a range of human diseases including metabolic disorders,inflammatory disease and carcinoma in the gastrointestinal tract and liver.In this review,we depict the role of ACSs in fatty acid metabolism,possible molecular mechanisms through which they exert functions,and their involvement in hepatocellular and colorectal carcinoma,with particular attention paid to long-chain fatty acids and small-chain fatty acids.Additionally,the liver-gut communication and the liver and gut intersection with the microbiome as well as diseases related to microbiota imbalance in the liver-gut axis are addressed.Moreover,the development of potentially therapeutic small molecules,proteins and compounds targeting ACSs in cancer treatment is summarized.

Impact of Chain Length of Saturated Fatty Acids during Their Heterogeneously Catalyzed Deoxygenation

Fatty acids with different chain length were deoxygenated in the absence of hydrogen (caprylic acid (CA), lauric acid (LA) and stearic acid (SA)). The catalytic tests were carried over Pd-containing catalysts out in a batch reactor under inert gas for 6 h at 250&degC to 350&degC and pressures from 18 to 75 bar in the absence of additionally fed hydrogen. Pd-containing catalysts were tested;the best performing catalyst was 10% Pd/C with 63% undecane yield at 327&degC. These catalysts were used for a comparative decarboxylation of CA, LA and SA. At equal reaction conditions (300&degC, 6 h), the chain length of the fatty acid had a strong impact on the conversion, which was steadily increasing, whereas the alkane selectivity ran through a maximum. This work demonstrated the usability of Pd-containing catalysts for the decarboxylation of various fatty acids in the absence of additionally fed hydrogen with respect to the manufacture of hydrocarbons that can be used as blending components for fuels.

脂肪酸对延边牛前体脂肪细胞UCP1、UCP3的mRNA表达的影响

试验旨在探索前体脂肪细胞受到冷应激后的响应机制,并初步鉴定以单不饱和脂肪酸中的油酸(OA)、肉豆蔻油酸(MOA)对解偶联蛋白1(UCP1)、解偶联蛋白3(UCP3)基因表达的影响,探索以OA、MOA为代表的单不饱和脂肪酸与细胞冷应激之间是否存在关联。以OA、MOA以及延边牛前体脂肪细胞作为试验材料,分别用OA、MOA处理前体脂肪细胞96 h,通过油红O染色和三酰甘油含量的测定来评估前体脂肪细胞内脂肪生成情况,利用qPCR测定UCP1、UCP3基因的相对表达量。再分别对未经处理、OA处理96 h、MOA处理96 h的前体脂肪细胞进行4℃冷应激处理0、6、12、24 h后,分别检测其UCP1、UCP3基因的相对表达量。结果显示:OA组与MOA组均可显著降低UCP1和UCP3基因的表达水平(P<0.05);在冷处理6~24 h后UCP1基因表达量发生显著性上升(P<0.05),冷处理6~12 h的UCP3基因表达量发生显著性降低(P<0.05)。试验发现,OA、MOA处理前体脂肪细胞96 h后,再进行4℃冷应激处理24 h,会导致UCP1基因表达量上升,而UCP3的表达量随着冷应激处理时间的延长而降低,并且试验初步验证了OA及MOA对两种基因具有抑制作用。

Olive oil consumption and non-alcoholic fatty liver disease

The clinical implications of non-alcoholic fatty liver diseases(NAFLD)derive from their potential to progress to fibrosis and cirrhosis.Inappropriate dietary fat intake,excessive intake of soft drinks,insulin resistance and increased oxidative stress results in increased free fatty acid delivery to the liver and increased hepatic triglyceride(TG)accumulation.An olive oil-rich diet decreases accumulation of TGs in the liver,improves postprandial TGs,glucose and glucagonlike peptide-1 responses in insulin-resistant subjects, and upregulates glucose transporter-2 expression in the liver.The principal mechanisms include:decreased nuclear factor-kappaB activation,decreased lowdensity lipoprotein oxidation,and improved insulin resistance by reduced production of inflammatory cytokines(tumor necrosis factor,interleukin-6)and improvement of jun N-terminal kinase-mediated phosphorylation of insulin receptor substrate-1.The beneficial effect of the Mediterranean diet is derived from monounsaturated fatty acids,mainly from olive oil.In this review,we describe the dietary sources of the monounsaturated fatty acids,the composition of olive oil,dietary fats and their relationship to insulin resistance and postprandial lipid and glucose responses in non-alcoholic steatohepatitis,clinical and experimental studies that assess the relationship between olive oil and NAFLD,and the mechanism by which olive oil ameliorates fatty liver,and we discuss future perspectives.

甘油二酯对可可脂类油脂结晶和巧克力起霜的影响研究进展

可可脂类油脂富含对称型单不饱和甘油三酯,通过科学调控可可脂类油脂中的甘油二酯,可优化巧克力的调温工艺,控制其起霜行为。综述了可可脂类油脂中甘油二酯的含量与种类(包括脂肪酸饱和度、链长和位置分布),探讨其对油脂结晶行为的作用规律,进而分析其对巧克力抗霜性能的影响。在适宜含量下1,3-甘油二酯可促进油脂形成巧克力需要的Ⅴ型晶体结构,而1,2-甘油二酯则倾向于使油脂形成Ⅱ~Ⅳ型晶体结构,且作用程度受脂肪酸链长的影响。然而,高含量甘油二酯无法使油脂形成Ⅴ型晶体结构。当甘油二酯含量在3%~5%时,油脂虽可形成Ⅴ型晶体结构,但需根据具体含量对结晶参数进行调整。因此,有必要通过分提、复配等技术对可可脂类油脂的甘油二酯进行调控。

牛油果油对肥胖小鼠体重、血清生化指标和肝脏中胆固醇代谢相关基因表达的影响

本试验旨在探究牛油果油对高脂饲粮诱导的肥胖小鼠体内胆固醇代谢的调节作用及其机制。用水代法提取牛油果油,采用气相色谱-质谱联用法检测其脂肪酸组成;采用60%高脂饲粮喂养C57BL/6J雄性小鼠构建肥胖模型,造模成功后,以325、650和975 mg/(kg·d)剂量的牛油果油分组灌胃4周。灌胃结束后,测定肥胖小鼠的体重和血清生化指标,对肝脏和脂肪组织进行组织病理学观察,并检测肝脏胆固醇代谢相关基因的表达情况。结果显示:牛油果油中的主要脂肪酸成分为油酸、棕榈油酸、亚油酸、棕榈酸和13-十八碳烯酸,其中油酸占比为55.56%。325、650和975 mg/(kg·d)牛油果油干预可显著降低肥胖小鼠体重增加量(P<0.001)和肝脏系数(P<0.05),使肥胖小鼠血清谷丙转氨酶(ALT)活性显著降低(P<0.001),血清高密度脂蛋白胆固醇(HDL-C)含量显著增加(P<0.05),并改善肥胖小鼠肝脏和脂肪组织脂质沉积;此外,650和975 mg/(kg·d)牛油果油干预还可使肥胖小鼠血清总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)含量和谷草转氨酶(AST)活性显著降低(P<0.01)。在胆固醇代谢相关基因表达方面,325、650和975 mg/(kg·d)牛油果油干预使肥胖小鼠肝脏中FXR的mRNA相对表达量显著下调(P<0.05),肝脏中ATP结合盒转运体G5(ABCG5)、ATP结合盒转运体G8(ABCG8)和胆固醇7α-羟化酶(CYP7A1)的mRNA相对表达量显著上调(P<0.05);650和975 mg/(kg·d)牛油果油干预显著上调了肥胖小鼠肝脏中肝X受体(LXR)、腺苷酸活化蛋白激酶α(AMPKα)的mRNA相对表达量(P<0.05),显著下调了肝脏中固醇调控元件结合蛋白2(SREBP2)的mRNA相对表达量(P<0.05);325和650 mg/(kg·d)牛油果油干预显著下调了肥胖小鼠肝脏中ATP结合盒转运体G1(ABCG1)的mRNA相对表达量(P<0.05);975 mg/(kg·d)牛油果油干预显著上调了肥胖小鼠肝脏中胆固醇27α-羟化酶(CYP27A1)的mRNA相对表达量(P<0.05)。由此可见,牛油果油能调节由高脂饲粮诱导的小鼠脂质代谢紊乱,抑制胆固醇的生物合成,促进胆固醇排出和胆汁酸合成。

高单不饱和脂肪酸液体鼻饲对急性脑卒中取栓术后患者糖脂代谢影响的动态分析

目的 动态分析高单不饱和脂肪酸液体鼻饲对急性脑卒中取栓术后患者糖脂代谢的影响。方法 纳入2021年1月至2022年9月上海市第六人民医院100例脑卒中取栓术后患者为研究对象,采用随机数字表法随机分为对照组和干预组,每组50例。对照组采用传统鼻饲方案进行肠内营养支持治疗,干预组予以高单不饱和脂肪酸液体鼻饲喂养。动态监测两组糖脂代谢指标,分析高单不饱和脂肪酸液体饮食对急性脑卒中患者糖脂代谢影响,并比较两组患者营养指标、氧化应激指标及不良反应。结果 两组第1个24 h血糖及胆固醇变异系数比较差异无统计学意义(P>0.05),第2个24 h及第3个24 h血糖及胆固醇变异系数干预组低于对照组(P<0.05);鼻饲结束后,两组内皮型一氧化氮合酶(eNOS)、丙二醛(MDA)、超氧化物歧化酶(SOD)水平均改善,且干预组MDA水平低于对照组,eNOS、SOD水平高于对照组(P<0.05);两组不良反应发生率比较差异无统计学意义(P>0.05)。结论 高单不饱和脂肪酸液体鼻饲可为急性脑卒中取栓术后患者提供营养,并可有效维持糖脂代谢平衡,降低患者应激反应,且不增加患者不良反应发生率。

Acyl-CoA synthase ACSL4:an essential target in ferroptosis and fatty acid metabolism

Long-chain acyl-coenzyme A(CoA)synthase 4(ACSL4)is an enzyme that esterifies CoA into specific polyunsaturated fatty acids,such as arachidonic acid and adrenic acid.Based on accumulated evidence,the ACSL4-catalyzed biosynthesis of arachidonoyl-CoA contributes to the execution of ferroptosis by triggering phospholipid peroxidation.Ferroptosis is a type of programmed cell death caused by iron-dependent peroxidation of lipids;ACSL4 and glutathione peroxidase 4 positively and negatively regulate ferroptosis,respectively.In addition,ACSL4 is an essential regulator of fatty acid(FA)metabolism.ACSL4 remodels the phospholipid composition of cell membranes,regulates steroidogenesis,and balances eicosanoid biosynthesis.In addition,ACSL4-mediated metabolic reprogramming and antitumor immunity have attracted much attention in cancer biology.Because it facilitates the cross-talk between ferroptosis and FA metabolism,ACSL4 is also a research hotspot in metabolic diseases and ischemia/reperfusion injuries.In this review,we focus on the structure,biological function,and unique role of ASCL4 in various human diseases.Finally,we propose that ACSL4 might be a potential therapeutic target.

7种经济贝类生殖腺脂肪酸含量的研究

为了提高文蛤等经济贝类的稚贝成活率,对文蛤等7种经济贝类的生殖腺中脂肪及脂肪酸的含量进行了研究.试验结果表明:不同的贝类总脂肪含量不同,其中,缢蛏最高,可达25.48%,虾夷扇贝22.32%,文蛤21.27%,泥蚶19.89%,紫贻贝16.79%,杂色鲍15.75%, 青蛤含量最低,只有14.88%.由于浙江沿海的缢蛏一般是在10～11月产卵、受精及完成胚胎发育,在这种低温条件下配子的成熟和受精卵发育需要大量的能量,缢蛏的脂肪含量为最高,精巢为11.02%(占所取样品干重),卵巢为14.46%.雌雄生殖腺的脂肪含量也不同,一般是雌性生殖腺脂肪含量明显高于雄性生殖腺.不饱和脂肪酸的含量大于饱和脂肪酸,其中,紫贻贝含量最高,为67.23%,文蛤次之67.19%,泥蚶第三64.27%,虾夷扇贝59.74%,缢蛏59.40%,青蛤最低,仅为57.51%.生殖腺的质量是繁殖成败的关键,其中脂质的积累是影响生殖腺发育的主要因素之一.