Osthole Improves Cognitive Function of Vascular Dementia Rats: Reducing Aβ Deposition via Inhibition NLRP3 Inflammasome

Vascular dementia (VD) is a common neurodegenerative disease, and the cognitive dysfunction is a major manifestation of VD. Lots of evidences showed that beta-amyloid (A beta) deposition and neuroinflammation act as vital elements in the progress of VD. The previous studies showed that osthole (OST) can improve the cognitive function of VD and Alzheimer's disease (AD). However, the effect of OST on A beta in VD brain is still unclear. Chronic cerebral hypoperfusion (CCH) of rats were used to investigate the effect of OST on A beta through nod-like receptor protein 3 (NLRP3) inllammasome in this study. Morris Water Maze and V-maze were used to test the spatial learning, memory and working abilities. Hematoxylin eosin (H&E) and Nissl staining were used to observe the morphology and number of hippocampal neurons. Immunofluorescence staining was used to observe the number of microglia activated. Western blot was used to detect the expression of proteins. The study results showed that OST obviously enhanced the spatial learning, memory and working abilities induced by modified bilateral common carotid artery occlusion (BCCAO) in rats, improved the pathological damage of hippocampal neurons induced by BCCAO in rats, inhibited the activation of microglia induced by BCCAO in rats. Furthermore, this study also discovered that OST reduced A beta deposition in VD hippocampus via inhibition the NLRP3 inflammasome. Together, these results suggest that OST reduces A beta deposition via inhibition NLRP3 inllammasome in microglial in VD.