中文摘要：

综述了近年来microRNAs，尤其是miR－33在脂质代谢调控方面的功能研究进展．脂质代谢在细胞水平进行有规律的调控，主要参与者有肝X受体（LXRs）和固醇调节元件结合蛋白（SREBPs）等．最近研究发现，非编码RNAs家族成员microRNAs在转录后水平调节脂质代谢相关基因表达，参与胆固醇、甘油三酯和脂肪酸代谢．其中miR-33可靶向沉默三磷酸脂苷结合盒（ABC）转运体家族成员ABCAl和ABCGl，抑制胆固醇流出和高密度脂蛋白（HDL）合成；通过靶向沉默脂肪酸β-氧化相关基因，如CPTlA、CROT和HADHB表达，抑制脂肪酸氧化；还可沉默AMPK和RIPl40的表达，影响甘油三酯代谢．其他microRNAs如miR．122、miR-370、miR－125a－5p、miR－27、miR－320等，也参与调控胆固醇、甘油三脂、脂肪酸代谢及脂肪细胞分化．

英文摘要：

Lipid metabolism is tightly regulated at the cellular level, in addition to classic transcriptional regulation of cholesterol metabolism （e.g. by SREBP and LXR）. Members of a class of non-coding RNAs termed microRNAs have recently been identified to be potent post-transcriptional regulators of lipid metabolism genes, including metabolisms of cholesterol, triglyceride, and fatty acid. Several reports have recently shown that miR-33 regulates cholesterol efflux and HDL biogenesis by downregulating the expression of the ABC transporters, ABCA1 and ABCG1. Moreover, miR-33 also inhibits the translation of several transcriptional regulating proteins for fatty acid β-oxidation, including CPT1A, CROT, and HADHB, thereby inhibiting fatty acid degradation. In addition, miR-33 may regulates triglyceride metabolism through negatively regulating the activity of AMPK and RIP140. Other microRNAs including miR-122, miR-370, miR-125a-5p, miR-27 and miR-320 have been shown to play important roles in regulating cholesterol homeostasis, triglyceride, fatty acid metabolism and lipogenesis. The current progress of the microRNAs, especially miR-33, in regulating lipid metabolism were summarized.