Hippocampal proteins discovery of Panax quinquefolius and Acorus gramineus ameliorating cognitive impairment in diabetic rats.

Abstract

Early diagnosis of diabetic cognitive impairment (DCI) and investigation of effective medicines are significant to prevent or delay the occurrence of irreversible dementia. In this study, proteomics was applied to investigate the changes of hippocampal proteins after administration of Panax quinquefolius-Acorus gramineus (PQ-AG) to DCI rats, with a view to discover the differentially expressed proteins of PQ-AG action and elucidated the potential biological relationships. The model and PQ-AG group rats were injected intraperitoneally with streptozotocin, and the PQ-AG group rats were continuously administered with PQ-AG. Social interaction and Morris water maze were performed to evaluate the behavior of rats on the 17th week after the model was established, and DCI rats were screened out from the model group by a screening approach. The hippocampal protein differences were investigated with proteomics in DCI and PQ-AG-treated rats. The learning and memory abilities and contact duration of DCI rats were improved after 16weeks of PQ-AG administration. Altogether, 9 and 17 differentially expressed proteins were observed in control versus DCI rats and in DCI versus PQ-AG-treated rats, respectively. Three proteins were confirmed with western blotting analyses. These proteins were mainly involved in the pathways of JAK-STAT, apoptosis, PI3K/AKT, fork-head box protein O3, fructose, and mannose metabolism. This suggested that PQ-AG ameliorated cognitive impairment of diabetic rats by influencing the above pathways and providing an experimental basis for the mechanism of DCI and PQ-AG.