Methotrexate (MTX) is commonly employed in cancer treatment, but its clinical use is restricted due to the MTX‐associated renal injury. This study investigates the combined potential of Rhus coriaria (sumac) and bone marrow mesenchymal stem cells (BMMSCs) against MTX‐induced nephrotoxicity in rats. The high‐resolution‐liquid chromatography‐mass spectrometry (HR‐LC‐MS) of sumac extract tentatively identified 22 phytochemicals, mostly flavonoids, anthocyanins, and steroids. Preparation of sumac liposomes attained a suitable particle size of 3041.33 ± 339.42 nm, a polydispersity index of 0.208 ± 0.086, and an encapsulation efficiency of 84.92 ± 3.47%. Rat BMMSCs were injected into the tail vein of the experimental rats (0.5 × 106 cells, intravenous [iv]) of seven treated groups. The experimental design relies on either pre‐ or posttreatment of rats with intraperitoneal (IP) sumac liposomes (SL) (200 mg/kg, daily with a dose of MTX (300 µg/kg/14 days). The histopathological examination and serum analysis of creatinine and urea revealed good results, besides regulating levels of oxidative stress and inflammatory markers. Additionally, a significant decrease in the gene expression levels of B‐Cell Lymphoma 2 (Bcl‐2) and caspases‐3 and −9, a remarkable increase in the Bcl‐2 Associated X‐Protein (Bax), nuclear factor erythroid 2‐related factor 2 (Nrf2), and heme‐oxygenase 1 expression, and a downregulation of Kelch‐like ECH‐associated protein 1 (Keap1). Collectively, the coadministration of SL with BMMSCs might be a potent therapeutic strategy for attenuation of MTX‐induced renal damage. The network pharmacology analysis identified the involved key hub genes as KEAP1, Nrf2, HMOX1, mitogen‐activated protein kinase (MAPK1), nuclear factor‐kappa B (NF‐KB), interleukin‐1 beta (IL‐1B), and caspase‐3. The docking results revealed strong binding affinities of 7‐O‐methyl‐cyanidin‐3‐O‐(2″‐galloyl)‐galactoside with Keap1 and amentoflavone with MAPK. These insights pave the way for future experimental validation and therapeutic development of sumac‐based phytoconstituents against MTX‐induced nephrotoxicity.
