Effect of silymarin supplementation and continuous and high intensity interval training on liver enzymes and histological modifications in rats with dexamethasone-induced nonalcoholic fatty liver disease

The purpose of this study was to evaluate the effect of continuous and high intensity interval training with silymarin consumption on liver enzymes and histological modifications in rats with dexamethasone-induced nonalcoholic fatty liver disease. Male rats were initially divided into 2 groups: normal and exposed to dexamethasone. Dexamethasone group were randomly divided into 6 groups. control (C), Silymarin (S), continues training (CT), and continues training+silymarin (CTS), high intensity interval training (HIT), high intensity interval training+Silymarin (HITS). Silymarin groups, received 300 mg. kg-1.d-1 of silymarin solution through gavage. Animals in HIT groups performed 3-min bouts at 40 m/min, interspersed by 3-min active recovery at a running velocity of 20 m/min on a motorized treadmill with 15% incline, repeated six times per session. Continues training groups performed steady state running at the same speed as the active recovery's speed in the HIT group. Liver histological modifications and serum levels of alanine aminotransferase (ALT) and Aspartate transaminase (AST) were measured. Silymarin consumption and aerobic training were able to improve histological changes compared with control group. Interactive effect of silymarin supplementation and training on AST and ALT levels was not significant. Silymarin reduced liver AST and ALT levels (p≤0.05). Also, AST levels were significantly higher in HIT group than in control group (p≤0.05). The amount of this enzyme in the HITS was significantly reduced compared to HIT group (p≤0.05). Silymarin supplementation and aerobic training separately and in combination may improve liver histological status of rats with dexamethasone-induced nonalcoholic fatty liver.