摘要
目的:分析苜蓿皂苷提取物对正常和脂变Buffalo大鼠肝细胞(BRL细胞)中Ldlr、LXRα和FXR m RNA表达的影响,进而初步探讨苜蓿皂苷调节脂质代谢及降低机体胆固醇含量的机制。创新点:苜蓿皂苷具有调节脂质代谢,降低机体胆固醇含量的作用,但是目前对其机理研究并不多,特别是在细胞水平上。本试验以BRL细胞为对象,研究苜蓿皂苷对胆固醇代谢相关基因表达的影响,从而探究苜蓿皂苷在细胞水平上对胆固醇代谢的调节作用。方法:通过50%胎牛血清诱导BRL细胞48 h建立细胞脂肪变性模型,运用实时荧光定量聚合酶链式反应(q RT-PCR)检测正常和脂变BRL细胞Ldlr、LXRα和FXR m RNA的表达,从而得出各处理组BRL细胞内Ldlr、LXRα和FXR m RNA表达的变化。结论:(1)添加苜蓿皂苷后,正常BRL细胞中Ldlr m RNA的表达量显著上调,脂变BRL细胞Ldlr m RNA的表达有增加的趋势;(2)苜蓿皂苷可以显著下调正常和脂变BRL细胞中LXRα和FXR m RNA的表达。因此,在细胞水平上,苜蓿皂苷可能通过促进Ldlr的表达,抑制LXRα和FXR的表达,从而调节BRL细胞胆固醇的代谢。
We studied the effects of alfalfa saponin extract(ASE) on low density lipoprotein receptor(Ldlr), liver X receptor α(LXRα), and farnesoid X receptor(FXR) in normal and hyperlipidemic Buffalo rat liver(BRL) cells. Normal and hyperlipidemic BRL cells were divided into eight groups: normal, or normal cells treated with 50, 100, and 150 mg/L ASE, hyperlipidemic, or hyperlipidemic cells treated with 50, 100, and 150 mg/L ASE. After treatment for 24 h, Ldlr, LXRα, and FXR m RNA expression levels were measured by quantitative real-time polymerase chain reaction(q RT-PCR). Data showed that m RNA expression of Ldlr in normal BRL cells was significantly up-regulated by ASE treatment and m RNA expressions of LXRα and FXR were significantly down-regulated both in normal and hyperlipidemic BRL cells after ASE treatment. Thus, ASE might ameliorate hepatic steatosis by regulating genes involved in cholesterol metabolism, including up-regulation of Ldlr as well as down-regulation of LXRα and FXR.
基金
Project supported by the National Natural Science Foundation of China(No.31301983)
the Earmarked Fund for Modern Agro-industry Technology Research System of China(No.CARS-35)