Captopril attenuates oxidative stress and neuroinflammation implicated in cisplatin-induced cognitive deficits in rats.

RATIONALE

One of the most debilitating drawbacks of cisplatin chemotherapy is neurotoxicity which elicits memory impairment and cognitive dysfunction (chemobrain). This is primarily triggered by oxidative stress and inflammation. Captopril, an angiotensin-converting enzyme inhibitor, has been reported as a neuroprotective agent owing to its antioxidant and anti-inflammatory effects.

OBJECTIVE

We examined the possible neuroprotective effect of captopril against cisplatin-induced neurological and behavioral abnormalities in rats.

METHODS

Chemobrain was induced in rats by cisplatin (5 mg/kg, i.p.) on the 7th and 14th days of the study while captopril was administered orally (25 mg/kg) daily for three weeks. The effects of captopril were assessed by performing behavioral tests, histological examination, and evaluation of oxidative stress and inflammatory markers.

RESULTS

Cisplatin caused learning/memory dysfunction assessed by passive avoidance and Y-maze tests, decline in locomotion, and rotarod motor balance loss which were further verified by neurodegeneration observed in histological examination. Also, cisplatin aggravated oxidative stress by elevating lipid peroxidation (MDA) levels and diminishing catalase activity. Moreover, cisplatin upregulated the neuroinflammatory markers (TNF, IL-6, GFAP, and NF-κB). Captopril successfully ameliorated cisplatin damage on the levels of neurobehavioral and histopathological changes. Mechanistically, captopril significantly diminished MDA production and preserved catalase antioxidant activity. Captopril also counteracted neuroinflammation through inhibiting NF-κB and its downstream proinflammatory cytokines besides repressing astrocyte activity by reducing GFAP expression.

CONCLUSION

Our findings revealed that captopril could abrogate cisplatin neurotoxicity via reducing oxidative stress and neuroinflammation thus enhancing cognitive and behavioral performance. This could suggest the repurposing of captopril as a neuroprotective agent, especially in hypertensive cancer patients receiving cisplatin.