二酰基甘油酰基转移酶1在脂肪代谢和奶牛酮病中的作用

Role of diacylglycerol acyltransferase 1 in fat metabolism and ketosis in dairy cows

酮病是奶牛围产期高发的营养代谢性疾病,剧烈的脂肪分解是导致奶牛酮病的重要因素之一,即酶促分解脂肪组织中的甘油三酯(TG)。二酰基甘油酰基转移酶1(DGAT1)由9个跨膜α螺旋(TM1至TM9)和3个loop区(EL1、IL1、IL2)构成,在TG合成过程中可以催化甘油二酯(DG)的酰基化这一关键反应。DGAT1在脂肪代谢中参与脂肪吸收和能量代谢过程,并调控脂蛋白的转运通量以及血浆中脂质浓度。此外,DGAT1还能通过增强脂质合成基因的表达,抑制脂解相关基因的表达,从而改善酮病奶牛的脂肪分解功能。文章深入探讨了DGAT1的结构及其在TG合成和脂肪代谢中的关键作用,以期为奶牛酮病的预防和治疗提供参考依据。

Ketosis is a highly prevalent nutritional and metabolic disease in dairy cows during the periparturient period,and intense lipolysis is one of the most important factors contributing to ketosis in dairy cows,which is the enzymatic catabolism of triglyceride(TG)in adipose tissue.Diacylglycerol acyltransferase 1(DGAT1),which consists of nine transmembraneα-helices(TM1 to TM9)and three loops(EL1,IL1,and IL2),catalyzes the acylation of diacylglycerol(DG),a key reaction during TG synthesis.DGAT1 can participate in fat uptake and energy metabolism in lipid metabolism,and regulate the transport flux of lipoproteins as well as plasma lipid concentration.In addition,DGAT1 improves adipose tissue catabolism in ketosis cows by enhancing and regulating the expression of lipid synthesis genes and suppressing the expression of lipolysis-related genes.In this paper,the structure of DGAT1 and its key role in TG synthesis and lipid metabolism are discussed in depth,with a view to providing theoretical references and bases for the occurrence and prevention of ketosis in dairy cows.