Melatonin attenuates thioacetamide-induced liver fibrosis in male rats through modulation of interleukin-6, interleukin-4, apoptosis and urokinase plasminogen activator receptor-associated protein/Endo180.

Liver fibrosis is a chronic progressive disease, its resolution still unclear, and the current study explored the role of melatonin in modulation of interleukin-6 (IL-6), interleukin-4 (IL-4), transforming growth factor beta1 (TGF-β1) and urokinase plasminogen activator receptor-associated protein/Endo180 (uPARAP/Endo180) pathway in thioacetamide (TAA)-induced hepatotoxicity. Thirty two adult Sprague-Dawley rats were divided into four groups: vehicle control group, TAA-induced liver fibrosis group that was left untreated, melatonin administration before and along with TAA and melatonin along with TAA group. TTA-induced massive liver necrosis, fibrosis around portal tract and increases serum levels of liver enzymes and total bilirubin when compared with control vehicle group. While both melatonin pretreatment and treatment retained liver parenchyma and liver enzymes quite similar to control group and reduced TAA-induced liver injury. Notably, melatonin pretreatment and treatment increased collagen degradation in TAA liver injury by19, 31.7-fold respectively evidence by collagen percentage area. Melatonin also decreased the amount of thiobarbituric acid reactive compounds and retained the reduced glutathione and superoxide dismutase to basal level quite similar to control group. Additionally, melatonin significantly (P value ≤0.05) decreased the levels of TGF-β1, epidermal growth factor (EGF), hydroxyproline, tissues IL-6, caspase-3, and receptor interacting serine/threonine kinase1 (RIPK1), fibrillin-1, and - smooth muscle actin in the liver tissues while significantly (P value ≤0.05) increasing the levels of IL-4 and uPARAP/Endo180. Due to its anti-inflammatory, anti-apoptotic, and antioxidant capabilities as well as its ability to decrease hepatic stellate cell activation and fibrogenesis, these data imply that melatonin has a powerful anti-fibrotic effect.