Metformin ameliorates doxorubicin-induced cardiotoxicity targeting HMGB1/TLR4/NLRP3 signaling pathway in mice

Oxidative stress and inflammation have been linked to doxorubicin (DOX)-induced cardiotoxicity, while the exact molecular processes are currently under investigation. The goal of this study is to investigate Metformin's preventive role in cardiotoxicity induced by DOX. Male albino mice were divided randomly into 4 groups. Metformin (Met) 200 mg/kg orally (p.o.) was given either alone or when combined with a single DOX (15 mg/kg; i.p.). A control group of 5 mice was also provided. Met was initiated 7 days before DOX, lasting for 14 days. Besides, docking studies of Met towards HMGB1, NF-kB, and caspase 3 were performed. Heart weight, cardiac troponin T (cTnT), creatine kinase Myocardial Band (CK-MB) levels, malondialdehyde (MDA), and nitric oxide (NO) contents all increased significantly when comparing the DOX group to the control normal group. Conversely, there was a substantial decline in superoxide dismutase (SOD) and glutathione peroxidase (GSH). DOX group depicts a high expression of TLR4, HMGB1, and caspase 3. Immunohistochemical staining revealed an increase in NLRP3 inflammasome and NF-κB expressions alongside histopathological modifications. Additionally, Met dramatically decreased cardiac weight, CK-MB, and cTnT while maintaining the tissues' histological integrity. Inflammatory biomarkers, including HMGB1, TLR4, NF-κB, inflammasome, and caspase 3 were reduced after Met therapy. Furthermore, molecular docking studies suggested the antagonistic activity of Met towards HMGB1, NF-κB, and caspase 3 target receptors. According to recent evidence, Met is a desirable strategy for improving cardiac toxicity produced by DOX by inhibiting the HMGB1/NF-κB inflammatory pathway, thus preserving heart function.