肠道菌群代谢产物氧化三甲胺调控奶牛肝脏脂质沉积的可能机制

Possible Mechanism of Gut Microbiota Metabolite TrimethylamineOxide Regulating Liver Lipid Deposition in Dairy Cows

氧化三甲胺(TMAO)是一种具有生物活性的肠道菌群代谢产物。饲粮中胆碱、肉碱和甜菜碱经肠道菌群代谢生成三甲胺(TMA),大部分TMA在肝脏进一步被肝黄素依赖性单加氧酶(FMO)氧化为TMAO。近年来,众多研究发现血浆TMAO浓度与心血管疾病、慢性肾病、糖尿病、结直肠癌和非酒精性脂肪肝等疾病呈正相关关系,TMAO在畜禽脂肪沉积中的作用也被证实。本文综述了TMAO的代谢过程、生理功能及其在奶牛脂肪肝发生发展中的潜在作用,以期为高产奶牛脂肪肝发病机制、营养调控和防治研究提供新的方向与思路。

Trimethylamine oxide(TMAO)is a biologically active metabolite of the gut microbiota.Choline,betaine and carnitine in the diet are metabolized by the gut microbiota to produce trimethylamine(TMA),most of which is further oxidized to TMAO by flavin-containing monooxygenase(FMO)in the liver.In recent years,numerous studies have found that plasma TMAO concentration is positively correlated with cardiovascular disease,chronic kidney disease,diabetes,colorectal cancer and non-alcoholic fatty liver disease.The role of TMAO in fat deposition in livestock and poultry has also been confirmed.In this paper,the metabolic process,physiological function and potential role of TMAO in the occurrence and development of fatty liver in dairy cows were reviewed,in order to provide new directions and ideas for the pathogenesis,nutritional regulation and prevention of fatty liver in high-yield dairy cows.