Protective effects of Rosmarinus officinalis against methotrexate-induced hepatorenal toxicity in Wistar rats: Biochemical, histopathological, and immunohistochemical evaluation

Abstract

Background: Methotrexate (MTX) is one of the most frequently used chemotherapeutic and immunosuppressive agents; however, its clinical use is limited to hepatotoxicity and other organ toxicities associated with oxidative stress and inflammatory responses. Aim: The current study was conducted to evaluate the potential protective effect of the ethanolic extract of Rosmarinus officinalis against MTX-induced hepatorenal injury in Wistar rats. Methods: Hepatorenal toxicity was induced in Wistar rats via a single intraperitoneal administration of MTX (20 mg/kg). Rosemary extract was orally administered at doses of 100 and 200 mg/kg body weight. Liver function biomarkers (alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase), renal function parameters (urea and creatinine), and hematological indices were determined alongside oxidative stress markers (superoxide dismutase, catalase, glutathione peroxidase, glutathione, and Malondialdehyde) and levels of tumor necrosis factor-alpha (TNF-α). Hem atoxylin and eosin staining and immunohistochemical profiling were used for histopathological evaluation. Results: MTX caused a significant increase in liver enzymes, oxidative markers, and TNF-α while lowering antioxidant defenses. Histopathological examination revealed hepatocyte degeneration, vascular congestion, and inflammatory infiltration. Treatment with R. officinalis extract alleviated these changes in a dose-dependent manner, resulting in improved biochemical parameters and reduced tissue injury. Conclusion: Rosmarinus officinalis extract may exert protective effects against MTX-induced hepatorenal injury through antioxidant and anti-inflammatory mechanisms. However, further studies are required to confirm these effects and validate their therapeutic potential.