Ginsenoside compound K attenuates cognitive deficits in vascular dementia rats by reducing the Aβ deposition

Abstract

Ginsenoside compound K (CK) is the main metabolite of protopanaxadiol-type ginsenosides and has been demonstrated to exert neuroprotective and cognition-enhancing effects. The effects of CK on cognitive function in vascular dementia (VD) has not been elucidated. Therefore, the present study aims to elucidate the effects of CK on memory function as well as its potential mechanism in VD rats. Sprague–Dawley rats were subjected to Chronic Cerebral Hypoperfusion (CCH) by permanent bilateral common carotid artery occlusion (2VO). CCH induced neuronal damage and aggravated the aggregation of Amyloid-β1-42 peptides (Aβ1-42), which plays a critical role in the neurotoxicity and cognitive impairment. CK treatment attenuated CCH-induced Aβ1-42 deposition and ameliorated cognition impairment. Furthermore, CK enhanced the activity of the pSer9-Glycogen synthase kinase 3β (pSer9-GSK3β) and the insulin degrading enzyme (IDE), which mainly involved the production and clearance of Aβ1-42. Moreover, CK treatment enhanced the activity of protein kinase B (PKB/Akt), a key kinase in phosphatidylinositol 3 kinase (PI3K)/Akt pathway that can regulate the activity of GSK-3β and IDE. In short, our findings provide the first evidence that CK might attenuate cognitive deficits and Aβ1-42 deposition in the hippocampus via enhancing the expression of pSer9-GSK-3β and IDE.