Chinese Prescription Kangen-karyu Attenuates Neuronal Damage and Improves Cognitive Function in Ischemic Stroke by Regulating ROS-Mediated MAPK Activation

OBJECTIVE Ischemic stroke is a leading cause of morbidity and mortality worldwide, largely due to the limited and inadequate therapeutic options currently available. As a result, developing new therapeutic approaches is crucial. This study aims to investigate the potential therapeutic effects of Kangen-karyu (KK), a compound that has garnered significant attention for its diverse biological functions, in mitigating brain damage induced by cerebral ischemia/reperfusion. METHODS Seven to eight-week-old male C57BL/6J mice underwent either sham surgery or bilateral common carotid artery occlusion (BCCAO) for 10 minutes, followed by reperfusion to induce cerebral ischemia/reperfusion injury. The mice were treated orally with either a vehicle, KK (200 mg/kg), or nimodipine (NP, 30 mg/kg), administered 2 hours before (Pre-KK) or after (Post-KK, Post-NP) BCCAO. The neurobehavioral performance of the mice was assessed. Additionally, histopathological changes, oxidative stress, inflammation, and apoptotic parameters were evaluated in brain tissues. RESULTS Infarct volume, brain water content, DHE, and Fluoro-Jade B staining confirmed that post-KK significantly ameliorated BCCAO-induced histopathological damage and neurobehavioral deficits compared to the pre-KK and post-NP groups. Additionally, administration of post-KK reduced the protein expression levels of phospho-c-Jun N-terminal kinase (p-JNK), phospho-p38, inducible nitric oxide synthase (iNOS), Bax, and caspase 3. In the cognition tests, BCCAO showed a decreased preference index and an increased alteration rate, which together indicate improved cognitive performance after post-KK. CONCLUSION Our study suggests that Kangen-karyu (KK) exerts a neuroprotective effect by reducing oxidative stress, inflammation, and apoptosis via the JNK/p38 pathway, indicating its potential as a therapeutic candidate for mitigating ischemia/reperfusion-induced brain damage.