Effect of Lactobacillus paracasei A221‐fermented ginseng on impaired spatial memory in a rat model with cerebral ischemia and β‐amyloid injection

Abstract

ABSTRACTAimGinseng, a traditional herbal medicine, has been shown to prevent the progression of dementia, but its therapeutic effects vary because ginseng's components must first be activated by intestinal bacteria before being absorbed into the blood. We therefore focused on a fermented ginseng (FG), which contains activated components prepared by Lactobacillus paracasei A221, and compared its effects with those of non‐FG. In this study, we investigated whether FG is effective on spatial memory impairment in rats.MethodsRats with spatial memory impairment were prepared with transient cerebral ischemia and intraventricular injection of β‐amyloid 1‐42 for 7 days (CI + Aβ). Oral FG or non‐FG was given for 7 days after the cerebral ischemia. Spatial memory was evaluated using the Morris water maze (MWM). We observed neuronal neuclei‐positive cells to assess hippocampal neuron loss, and investigated the protein expression of caspase‐3 and cleaved caspase‐3 for neuronal apoptosis, ionized calcium‐binding adapter molecule 1 (Iba‐1) for microglia, and glial fibrillary acidic protein for astrocytes.ResultsFG treatment in the CI + Aβ‐operated rats shortened the extended time to reach the platform in the MWM, whereas non‐FG treatment did not affect the extended time. FG ameliorated loss of hippocampal cornu amonis (CA)1 neurons and the increase in caspase‐3 and Iba‐1 in the CI + Aβ‐operated rats.ConclusionFG improved spatial memory impairment in CI + Aβ‐operated rats. The effect of FG might be attributed to the amelioration of apoptotic neuronal cell death and the inactivation of microglia. FG is a more useful treatment for patients with cognitive dysfunction than non‐FG.