Protective effect of probiotics and ascorbic acid on bile duct ligation-induced chronic hepatic encephalopathy in rats

BACKGROUND AND PURPOSE: Hepatic encephalopathy (HE) is a brain dysfunction caused by acute and chronic hepatic failure. The pathogenesis of HE is unknown, although small intestinal bacterial overgrowth associated with chronic liver damage, hyperammonemia, and oxidative stress are considered major factors for HE. Effective lowering of circulating ammonia and neuroinflammation is the main strategy for preventing and treating HE in cirrhosis. In the present study, the protective effect of probiotics (Lactobacillus plantarum and Bacillus clausii) and ascorbic acid in combination was assessed in bile duct ligation (BDL)-induced chronic HE in rats. EXPERIMENTAL APPROACH: Sprague Dawley rats were divided into five groups (n = 6). All groups were subjected to double ligation of the bile duct and fed a hyperammonemia diet, except group I (normal control). Groups III and IV were treated with a low and high dose of combination therapy, respectively, while group V was given lactulose. Four weeks post ligation, behavioral, biochemical, and neurochemical parameters were measured. The liver and brain were dissected for histopathology and protein analyses. FINDINGS / RESULTS: Combination therapy reduced plasma AST, ALT, ALP, and ammonia levels and attenuated hepatic inflammation/fibrosis in cirrhotic rats. Furthermore, combination therapy significantly improved behavioral parameters and restored the antioxidant enzyme activity. Histological changes were observed in the brain and liver of BDL animals. CONCLUSION AND IMPLICATIONS: The additive impact of probiotics and ascorbic acid on BDL-induced chronic HE in rats was mediated by a reduction in ammonia and oxidative stress, implying the therapeutic potential of combination therapy in HE.