Acyl-coenzyme A: cholesterol acyltransferase family

The enzymes of the acyl-coenzyme A:cholesterol acyltransferase(ACAT)family are responsible for the in vivo synthesis of neutral lipids.They are potential drug targets for the intervention of atherosclerosis,hyperlipidemia,obesity,type II diabetes and even Alzheimer’s disease.ACAT family enzymes are integral endoplasmic reticulum(ER)membrane proteins and can be divided into ACAT branch and acyl-coenzyme A:diacylglycerol acyltransferase 1(DGAT1)branch according to their substrate specificity.The ACAT branch catalyzes synthesis of cholesteryl esters using long-chain fatty acyl-coenzyme A and cholesterol as substrates,while the DGAT1 branch catalyzes synthesis of triacylglycerols using fatty acylcoenzyme A and diacylglycerol as substrates.In this review,we mainly focus on the recent progress in the structural research of ACAT family enzymes,including their disulfide linkage,membrane topology,subunit interaction and catalysis mechanism.

普洱茶提取物对饮食诱导肥胖大鼠脂质合成相关基因表达的影响

目的观察普洱茶提取物(PTE)对饮食诱导性肥胖大鼠脂质合成相关基因的影响,探讨普洱茶抗肥胖的作用机制。方法30只雄性Sprague-Dawley大鼠随机分为3组(n=10):正常对照组,普通饲料;高脂组,高脂饲料;高脂+PTE组,高脂饲料+PTE。采用高脂饲料建立肥胖大鼠模型,测定大鼠体重和脂肪组织重量,判定减肥效果;采用real-timePCR检测PTE对脂质合成相关基因的表达影响。结果PTE能有效减轻动物体重和脂肪组织重量,显著下调二酰基甘油酰转移酶-1(DGAT1)、固醇辅酶A去饱和酶1(SCD1)和固醇调节元件结合蛋白(SREBP)-1cmRNA的表达。结论PTE可通过调节脂质合成相关基因,减少脂肪的合成,达到预防肥胖的作用。