Thioacetamide (TAA) is one of the common fungicidal agents that induce liver injury varying from inflammation, necrosis, and fibrosis to cirrhosis. Many recent studies reported the beneficial effect of probiotics and silymarin on hepatotoxicity regardless the causative agents. Therefore, the present study aimed to evaluate the ameliorative role of probiotics and/or silymarin on TAA induced hepatotoxicity in rats via histological, and immunohistochemical methods. Twenty five male albino rats were used for this experiment and were divided into five groups (n=5 rats/group); group I acts as negative control, group II was orally administrated distilled water for six weeks, then injected with TAA (200 mg/kg b.wt./ 5 ml physiological saline/ I.P.) twice a week for another six weeks, group III was treated with probiotics at a dose of 135 mg/ kg b.wt. orally in drinking water daily for six weeks, then injected with TAA (dosage of group II), twice weekly for another six weeks, group IV was treated with silymarin at a dose of 200 mg/ kg b.wt orally 4 times per week for six weeks, then injected with TAA (dosage of group II), twice weekly for another six weeks and group V was treated with combination of both probiotics and silymarin, at the same dosage in groups III and IV respectively then injected with TAA (dosage of group II), twice weekly for another six weeks. Histologically, TAA induced hepatocytes degeneration, inflammatory cells infiltration, and pseudolobular parenchyma as well as, high apoptosis and low proliferation rates that were proved by immunohistochemical staining for caspase 3 and ki-67 respectively. Probiotics and/or silymarin improved the histological feature of hepatocytes, reduced apoptosis and stimulated proliferation. Based on these results, we concluded that the use of probiotics and silymarin combination ameliorates the hepatotoxic effect of TAA in rats more than the use of probiotics or silymarin alone.
KEY WORDS: Thioacetamide; Probiotics; Silymarin; Liver; Histology; Immunohistochemistry.