内分泌学
内科学
酰基辅酶A
脂肪组织
脂肪酸合成
丙酮酸羧化酶
脂肪甘油三酯脂肪酶
辅酶A
酰基转移酶
胰岛素
脂肪酸合酶
生物
生物化学
化学
脂质代谢
酶
脂解
医学
还原酶
作者
Rupalie L. Meegalla,Jeffrey T. Billheimer,Dong Cheng
标识
DOI:10.1016/s0006-291x(02)02466-x
摘要
Glucose and insulin are anabolic signals which upregulate the transcriptions of a series of lipogenic enzymes to convert excess carbohydrate into triglycerides for efficient energy storage. These enzymes include ATP-citrate lyase (ACL), acetyl-coenzyme A carboxylase (ACC), fatty acid synthase (FAS), and glycerol-3-phosphate acyltransferase (G3PA). Acyl-coenzyme A:diacylglycerol acyltransferase (DGAT) is important to synthesize fatty acids into triglycerides. Two DGATs from different gene families have recently been identified. In the current study, we report that glucose preferentially enhances DGAT1 mRNA expression, whereas insulin specifically increases the level of DGAT2 mRNA. Treatment of adipocytes with glucose and insulin together results in higher DGAT activity in the membrane than cells treated with either of the agents alone, indicating that glucose and insulin have additive effect on DGAT activation. In mice treated with fast/refeeding protocol, DGAT2 mRNA decreased upon fasting and was replenished upon refeeding in adipose tissue and liver. This pattern of change was not observed for DGAT1. Inasmuch as DGAT1 mRNA is less abundant in liver, we suggest that DGAT1 is more involved in fat absorption in the intestine and in basal level triglyceride synthesis in adipose tissue where it is more highly expressed. In contrast, DGAT2 is more likely to play important roles in assembly of de novo synthesized fatty acids into VLDL particles in the liver.
科研通智能强力驱动
Strongly Powered by AbleSci AI