Abstract
Methotrexate (MTX) is a classical chemotherapeutic agent with nephrotoxicity as the most disturbing adverse effect. So far, its underlying molecular mechanisms, particularly PI3K/Akt/eNOS transduction, are inadequately explored. Several antioxidant modalities have been characterized to ameliorate MTX-induced renal injury. In this regard, Camel milk (CM) is a natural product with recognized antioxidant and anti-inflammatory features. Thus, the current study aimed to investigate the potential ameliorating effects of CM in MTX-induced kidney injury in rats. Renal tissues were studied in terms of renal injury markers, histopathology, oxidative stress, apoptosis and PI3K/Akt/eNOS signaling. CM was orally administered (10 ml kg-1) and the renal injury was induced by a single i.p. injection of MTX (20 mg kg-1). Interestingly, CM dose-dependently attenuated MTX-triggered increase of BUN and serum creatinine and renal Kim-1 expression and mitigated the renal histopathological changes. CM counteracted renal oxidative stress as manifested by lowering of lipid peroxides, restoration of NOX-1 levels and augmentation of the antioxidant defenses e.g., GSH, SOD, GPx and total antioxidant capacity. With respect to apoptosis, CM curbed the cleavage of PARP and caspase-3, downregulated p53, Bax and Cyt C proapoptotic signals and enhanced Bcl-2 and PCNA levels. In the same context, CM activated the prosurvival PI3K/Akt/eNOS pathway via enhancing PI3K p110, phospho-Akt and phospho-eNOS levels. Equally important, CM preconditioning did not interfere with MTX cytotoxicity in TK-10 or PC-3 cancer cells. Together, the current findings demonstrate, for the first time, the renoprotective effects of CM in MTX-induced kidney injury via activation of PI3K/Akt/eNOS signaling and combating oxidative stress and apoptosis.