[Experimental study on improvement of alcoholic liver disease by polysaccharides from Balanophora henryi through targeting miR-122a].

The aim of this paper was to investigate the effect of total polysaccharide from Balanophora henryi(TBP) on alcoholic liver disease(ALD) and explore the possible mechanism. C57 BL/6 N mice were randomly divided into 4 groups: pair-feeding group, alcohol-feeding model group, model+TBP group and TBP drug control group. The Gao-binge method was used to prepare the chronic ALD model, and at the same time, 400 mg·kg~(-1) TBP was given for interventional therapy. After feeding for 6 weeks, the serum, liver and colon tissues were collected for detection. As compared with the pair-feeding group, the model group mice showed obvious fatty degeneration and a large number of infiltration of inflammatory cells in the liver, with increased serum ALT and AST levels. After TBP intervention, histopathological changes in liver tissues were significantly improved, with decreased lipid deposition, closer arrangement of hepatocytes, lower expression level of inflammatory factors, and reduced activity of serum ALT and AST, indicating that TBP had a significant improvement effect on ALD. The observation of colonic tissues in mice showed that TBP effectively maintained the integrity of intestinal tissue structure of mice with ALD, enhanced the expression of tight junction protein occludin and reduced miR-122 a expression level. More importantly, TBP significantly reduced serum lipopolysaccharide(LPS) level in model mice. These results indicated that TBP may improve ALD by maintaining and enhancing intestinal barrier function. In vitro experiments showed that TBP significantly inhibited the expression level of miR-122 a in Caco-2 cells exposed to ethanol. Overexpression of miR-122 a in Caco-2 cells induced the inhibition of occludin protein production, and the addition of TBP significantly interfered with the effect. These results suggested that TBP could improve ALD by maintaining the stability of intestinal barrier function and reducing LPS content into the liver, and the mechanism may be partially related to inhibiting miR-122 a expression.