Zhuge Qun, Zhang Yi, Liu Biao, Wu Mingjuan
Department of Gastroenterology, Shangrao People's Hospital, Shangrao 334000, China.
Ann Palliat Med. 2020 May;9(3):1045-1054. doi: 10.21037/apm.2020.03.38. Epub 2020 May 7.
This study aims to explore blueberry polyphenols and its roles in nonalcoholic fatty liver disease (NAFLD) by relieving hepatic steatosis, and to understand alcoholic fatty liver disease (AFLD). Cell autophagy has been proved to promote lipid metabolism and is involved in the pathogenesis of AFLD; however, whether blueberry polyphenol affects autophagy is unknown. Therefore, our study analyzes the functions of blueberry polyphenol on AFLD and if its mechanisms are engaged with hepatocytes autophagy.
We built the AFLD mice model via alcohol abduction, and the TG lipid droplets content detected the hepatic steatosis through ORO and HE stains. For blood lipid levels measurements, serum CHOL and TG concentrations were tests. For mechanism analysis, the lipogenic genes of SREBP1, FAS, and ACCα, and the lipodieretic genes of ATGL and Sirt1 were evaluated by qRT-PCR, as well as the autophagy proteins of p62; WB measured LC3-I and LC3-II.
We found that chronic alcohol intake successfully induced AFLD occurrence with increased TG lipid droplets content in liver and serum CHOL and TG levels that accompanied by increased lipogenic and reduced lipodieretic mRNA levels, as well as enhancive p62 protein and decreased LC3-II/LC3-I proportion. However, after blueberry polyphenol intake, there were opposite outcomes happened. Moreover, blueberry polyphenol alone did not affect the lipid metabolism but promoted the hepatocytes autophagy at 200 mg/kg concentration.
In summary, we are unparalleled that illustrated blueberry polyphenols can prevent AFLD development by promoting autophagy to accelerate lipid metabolism than to lighten hepatic steatosis.
本研究旨在通过减轻肝脏脂肪变性来探索蓝莓多酚及其在非酒精性脂肪性肝病(NAFLD)中的作用,并了解酒精性脂肪性肝病(AFLD)。细胞自噬已被证明可促进脂质代谢,并参与AFLD的发病机制;然而,蓝莓多酚是否影响自噬尚不清楚。因此,我们的研究分析了蓝莓多酚对AFLD的作用及其机制是否与肝细胞自噬有关。
我们通过酒精诱导建立AFLD小鼠模型,通过油红O和苏木精-伊红(HE)染色检测肝脂肪变性的甘油三酯(TG)脂滴含量。检测血脂水平时,测试血清胆固醇(CHOL)和TG浓度。进行机制分析时,通过实时定量聚合酶链反应(qRT-PCR)评估固醇调节元件结合蛋白1(SREBP1)、脂肪酸合酶(FAS)和乙酰辅酶A羧化酶α(ACCα)的脂肪生成基因,以及脂肪甘油三酯脂肪酶(ATGL)和沉默信息调节因子1(Sirt1)的脂质分解基因,同时检测自噬蛋白p62;蛋白质免疫印迹法(WB)检测微管相关蛋白1轻链3(LC3)-I和LC3-II。
我们发现,长期摄入酒精成功诱导了AFLD的发生,肝脏中TG脂滴含量增加,血清CHOL和TG水平升高,同时脂肪生成mRNA水平升高,脂质分解mRNA水平降低,以及p62蛋白增加和LC3-II/LC3-I比例降低。然而,摄入蓝莓多酚后,出现了相反的结果。此外,单独的蓝莓多酚在200mg/kg浓度下不影响脂质代谢,但促进了肝细胞自噬。
总之,我们首次证明蓝莓多酚可通过促进自噬来加速脂质代谢,而非减轻肝脏脂肪变性,从而预防AFLD的发展。