Phenolic-Rich Aronia melanocarpa (cv. Nero) Extract Attenuates Doxorubicin-Induced Nephrotoxicity Associated with Reduced Oxidative Stress, Inflammation, and Endoplasmic Reticulum Stress

Aronia melanocarpa (black chokeberry) is a polyphenol-rich berry recognized as a functional food because of its potent antioxidant properties. This study investigated the phenolic composition, antioxidant capacity, and nephroprotective effects of A. melanocarpa extract (AME) against doxorubicin (DXR)-induced renal injury. Antioxidant activity was evaluated by determining total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity. Thirty-six female Sprague–Dawley rats (180–220 g) were randomly allocated to four groups (n = 9 per group): Control, AME, DXR, and AME + DXR. AME (200 mg/kg/day) was administered orally for 21 consecutive days as a pretreatment, and acute nephrotoxicity was induced by a single intraperitoneal injection of DXR (20 mg/kg) on day 21. Samples were collected 24 h after DXR administration. Renal injury was evaluated using biochemical, histopathological, oxidative stress (OS), inflammatory, endoplasmic reticulum stress (ERS), and apoptosis-related parameters, together with TUNEL staining. HPLC–PDA analysis of 29 targeted phenolic compounds identified cya-nidin-3-galactoside (2440 µg/g FW), cyanidin-3-arabinoside (350 µg/g FW), chlorogenic acid (251.83 µg/g FW), and rutin (32.29 µg/g FW) as the major constituents. DXR markedly impaired renal function and increased oxidative stress, ERS, inflammation, and apoptosis, whereas AME pretreatment significantly attenuated these alterations. These findings are consistent with a protective effect of phenolic-rich AME against acute DXR-induced renal injury in rats, associated with attenuation of oxidative stress, inflammation, ERS, and apoptosis. Further studies are needed to confirm these findings and evaluate their potential clinical relevance.