Naringenin Attenuates Methotrexate-Induced Nephrotoxicity Accompanied by Alterations in Oxidative Stress, Inflammatory, Apoptotic, and Endoplasmic Reticulum Stress Responses.

Methotrexate (MTX) is widely used in the treatment of malignancies and inflammatory disorders, but nephrotoxicity remains a major adverse effect. Naringenin (NAR), a natural flavonoid, has antioxidant, anti-inflammatory, and nephroprotective properties. This study investigated the potential protective effects of NAR against MTX-induced nephrotoxicity at biochemical, molecular, and histopathological levels. Forty-two adult male Wistar albino rats were assigned to seven groups (n = 6): Control, CMC (carboxymethyl cellulose), NAR100, MTX, and MTX combined with NAR (25, 50, or 100 mg/kg/day). NAR was administered for 7 days, with MTX given on day 3. Renal function, histopathology, and genes associated with oxidative stress, apoptosis, endoplasmic reticulum stress, and inflammation were evaluated. MTX administration caused marked renal damage, increased creatinine and BUN levels, elevated apoptosis-, inflammation-, and ER stress-related gene expression, and suppressed antioxidant defense-related genes. However, 50 and 100 mg/kg/day NAR attenuated these alterations, with greater effects at 100 mg/kg/day. Histopathological damage was attenuated by NAR treatment, although complete recovery was not observed. These findings suggest that NAR may protect against MTX-induced nephrotoxicity through the modulation of pathways associated with oxidative stress, inflammation, apoptosis, and ER stress. However, the persistence of certain histopathological alterations indicates that structural recovery of renal tissue may take a longer period compared with molecular changes.