Background: Tamoxifen (TAM) is a chemotherapeutic drug widely utilized to treat breast cancer. On the other hand, it exerts deleterious cellular effects in clinical applications as an antineoplastic agent, such as liver damage and cirrhosis. TAM-induced hepatic toxicity is mainly attributed to oxidative stress and inflammation. Pioglitazone (PIO), a peroxisome proliferator-activated receptor-gamma (PPAR-γ) agonist, is utilized to treat diabetes mellitus type-2. PIO has been reported to exert anti-inflammatory and antioxidant effects in different tissues. This research assessed the impact of PIO against TAM-induced hepatic intoxication.
Methods: Rats received PIO (10 mg/kg) and TAM (45 mg/kg) orally for 10 days.
Results: TAM increased aspartate aminotransferase (AST) and alanine aminotransferase (ALT), triggered several histopathological alterations, NF-κB p65, increased hepatic oxidative stress, and pro-inflammatory cytokines. PIO protects against TAM-induced liver dysfunction, reduced malondialdehyde (MDA), and pro-inflammatory markers along with improved hepatic antioxidants. Moreover, PIO, increased hepatic Bcl-2 expression while reducing Bax expression and caspase-3 levels. In addition, PIO decreased Keap-1, Notch1, and Hes-1 while upregulated HO-1, Nrf2, and SIRT1. Molecular docking showed the binding affinity of PIO for Keap-1, NF-κB, and SIRT1.
Conclusion: PIO mitigated TAM hepatotoxicity by decreasing apoptosis, inflammation, and oxidative stress. The protecting ability of PIO was accompanied by reducing Keap-1 and NF-κB and regulating Keap1/Nrf2/HO-1 and Sirt1/Notch1 signaling. A schematic diagram illustrating the protective effect of PIO against TAM hepatotoxicity. PIO prevented TAM-induced liver injury by regulating Nrf2/HO-1 and SIRT1/Notch1 signaling and mitigating oxidative stress, inflammation, and apoptosis.
Keywords: Hepatotoxicity; Notch1; Nrf2; Pioglitazone; Sitruin1; Tamoxifen.
© 2023. The Author(s).