β-Caryophyllene Ameliorates Thioacetamide-Induced Liver Fibrosis in Rats: A Preventative Approach.

Liver fibrosis is associated with increased rates of morbidity and mortality. At present, there are no specific treatments that can directly reverse hepatic fibrosis. The endocannabinoid system has been found to play a significant role in regulating the development and progression of liver diseases, in addition to having protective effects. In this study, we investigate the protective potential of β-Caryophyllene (BCP) against Thioacetamide (TAA)-induced liver fibrosis. Wistar rats were injected with TAA (200 mg/kg) three times per week for 8 weeks to induce liver fibrosis. They also received oral BCP before the TAA injections. AM630 (1 mg/kg) was administered to confirm the CB2 receptor-dependent effect of BCP. The BCP treatment (50 mg/kg) protected against cell injury and potentiated antioxidant defense by replenishing hepatic GSH, improving catalase activity, and inhibiting the formation of MDA. The co-administration of BCP mitigated the TAA-induced inflammatory response by decreasing the release of proinflammatory cytokines. Histological examination showed preserved cellular integrity, decreased collagen deposits with other extracellular matrix proteins, and low levels of myofibroblast activation. In addition, the BCP-treated rats demonstrated upregulated sirtuin 1 (SIRT1) expression, which had a direct inhibitory effect on hypoxia inducible factor (HIF-1α). AM630 pre-treatment inhibited all the aforementioned protective mechanisms of BCP. Based on our findings, BCP exerts protective effects in liver fibrosis, which can be attributed to its agonist action on CB2 receptors. This study provides preclinical evidence of the potential preventative benefits of BCP in liver fibrosis.