Although
cisplatin attacks various
tumors with remarkable efficacy, its clinical usage has been limited by its side effects, particularly nephrotoxicity.
Salubrinal, a selective eukaryotic translation
initiation factor 2 subunit α (eIF2α) dephosphorylation inhibitor, has been found to protect cells from endoplasmic reticulum (ER)-stress-induced cytotoxicity. In this study, we hypothesized that
salubrinal would protect against
cisplatin-induced nephrotoxicity in a mouse model.
Cisplatin treatment significantly increased serum blood
urea nitrogen and
creatinine levels, renal kidney injury marker (kim-1)
mRNA expression, renal cell apoptosis, and renal histopathological changes in mice. Unexpectedly, administration of
salubrinal significantly enhanced the
cisplatin-induced nephrotoxicity in mice.
Salubrinal by itself did not induce alterations in the function or histomorphology of mouse kidneys.
Salubrinal significantly enhanced the phosphorylation of eIF2α, the
protein expression of
activating transcription factor 4 and
CCAAT/enhancer binding protein homologous
protein, and the cleavage of
caspases 12, 9, and 3 in the kidneys of
cisplatin-treated mice. Moreover,
salubrinal enhanced the
cisplatin-induced oxidative stress in the kidneys. The
antioxidant N-acetylcysteine significantly reversed the increased renal lipid peroxidation, activated renal
caspase cascade, and increased blood BUN and
creatinine in
cisplatin-alone- or
cisplatin plus
salubrinal-treated mice. These findings suggest that
salubrinal aggravates
cisplatin-induced nephrotoxicity through the enhancement of oxidative stress and ER stress-related cell apoptosis.