Effect of Dangfei Liganning capsule on liver X receptor α/steroid regulatory element binding protein-1/fatty acid synthase signal pathway in rats with metabolic- associated fatty liver disease.

OBJECTIVE
To study the mechanism of Dangfei Liganning capsule in the treatment of rats with metabolic associated fatty liver disease (MAFLD).


METHODS
Totally 48 specific pathogen free Sprague-Dawley male rats were randomly divided into normal Group, model group, Dangfei Liganning high, moderate, and low-dose groups and Essentiale group which were fed with high fat diet for 8 weeks, and gavage and molding were carried out simultaneously. Dangfei Liganning high, middle and low-dose group were given 0.27, 0.135 and 0.0675 g·kg·d respectively by gavage, Essentiale group was given 0.123 g·kg·d by gavage, the same amount of distilled water was given by gavage in the normal group and the model group. The rats were weighed at the 0th week, 2nd week, 4th week, 6th week and 8th weekend respectively. The rats were sacrificed at the end of the 8th week. Serum levels of alanine aminotransferase (ALT), alanine aminotransferase (AST), triglyceride (TG), total cholesterol (CHO), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein (LDL-C), total protein (TP), albumin (Alb), globulin (GLB), total bilirubin (TBIL), direct bilirubin (DBIL), tumor necrosis factor-α(TNF-α) and interleukin-6 (IL-6) were measured. The levels of liver tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and liver pathology [hematoxylin and eosin (HE) staining, oil red O staining] were detected. The expression levels of liver X receptor α (LXRα), steroid regulatory element binding protein-1 (SREBP-1) and fatty acid synthase (FAS) were detected by immunohistochemistry, Western blot and reverse transcription-polymerase chain reaction reverse transcription-polymerase chain reaction.


RESULTS
From the beginning to the 8th week, the growth rate of body weight in the Dangfei Liganning high-dose group was slower than all other groups. There was no significant difference in ALB level in all groups ( 0.05). Compared with the model group, the levels of ALT, AST, LDL-C, TG, CHO, TP, GLB, TBIL, DBIL, IL-6, TNF-α were significantly decreased and HDL-C were significantly increased in Dangfei Liganning high-dose group (0.01, < 0.05). HE and oil red O staining showed that the fatty lesions in rat liver were alleviated, while the expressions of LXRα, SREBP-1, FAS mRNA and protein were significantly decreased (0.01).


CONCLUSIONS
Dangfei Liganning capsule can slow down the increase of body weight of MAFLD rats, reduce the levels of transaminase, Lipid and inflammatory factors in MAFLD rats, promote the synthesis of liver protein and bile metabolism, and improve the liver fatty lesion of MAFLD rats, among which the Dangfei Liganning high-dose group is more effective. The mechanism of action may be through blocking LXR-SREBP-1-FAS signal pathway.