Therapeutic effects of silymarin and naringin on methotrexate-induced nephrotoxicity in rats: Biochemical evaluation of anti-inflammatory, antiapoptotic, and antiautophagic properties

Silymarin (SLY) and naringin (NRG) are natural flavonoids that have been reported to have many benefits and medicinal properties. The present study was designed to investigate the protective effect of SLY and NRG against methotrexate (MTX)-induced nephrotoxicity in experimental animals. Rats were subjected to oral pretreatment of SLY (25 and 50 mg/kg body weight (b.w.)/day) and NRG (50 and 100 mg/kg b.w./day) for 7 days against renal toxicity induced by single intraperitoneal administration of MTX (20 mg/kg b.w.). MTX resulted in an increase in serum toxicity markers, lipid peroxidation, and reduction in activities of antioxidant enzymes. Additionally, MTX provoked inflammatory responses by increasing the levels of TNF-alpha, IL-1 beta, IL-6, NF-kappa B, and activation of COX-2 and iNOS. Furthermore, MTX administration caused apoptosis and autophagy by increasing activity of Caspase-3 and light chain 3B level. Conversely, SLY and NRG therapy significantly decreased these values in rats. This study demonstrated that SLY and NRG protect against MTX-induced nephrotoxicity.