Asiaticoside improves spatial learning and memory abilities of Alzheimer's disease rat model by promoting the expression of PPAγ and inhibiting inflammatory factors

Abstract

Aims: The present study is to investigate the effect of Asiaticoside (AS) on the expression of hippocampal Peroxisome Proliferator Activated Receptor Gamma (PPARγ) and inflammatory factors such as Interleukin (IL)-6 and Tumor Necrosis Factor (TNF)-α in rats after intracerebral injection of Aβ1-42. Methods: A total of 40 specific pathogen-free Sprague-Dawley rats were evenly divided into shamoperation (control) group, model group, model+AS (15 mg/kg) group and model+AS (45 mg/kg) group. Condensed β-amyloid protein (Aβ)-1-42 was slowly injected into the CA1 region in hippocampus of rats to simulate Alzheimer’s disease. Morris water maze test was used to examine the ability of spatial learning and memory of rats. Immunohistochemistry was performed to detect the deposition of Aβ1-42 in hippocampal tissues. Enzyme-linked immunosorbent assay was carried out to determine the contents of IL-6 and TNF-α in hippocampal tissues. Western blotting was employed to measure the protein expression of PPARγ. Results: Treatment with AS enhanced the spatial learning and memory, reduced the expression of Aβ1-42 in hippocampal region, decreased the contents of IL-6 and TNF-α in hippocampal tissues, and elevated the protein expression of PPARγ in hippocampal tissues of AD model rats. Conclusions: The present study demonstrates that AS improves spatial learning and memory abilities of AD model rats by promoting the expression of PPARγ and inhibiting the contents of inflammatory factors.