Noble Dendrobium Polysaccharides Attenuate Learning And Memory Deficits Induced By Lipopolysaccharide And Its Mechanisms In Rats

Objective:To investigate the protective effect of Noble dendrobium polysaccharides (NDP) on lipopolysaccharide (LPS)-induced learning and memory deficits in rats, and explore the active mechanisms.Methods:Treated with NDP (40,80,160mg·kg-1·d-1) for 7 days, the rat model with learning and memory deficits was induced by injection of LPS 20μg (2μg·μl-1) into the lateral ventricle. The abilities of spatial learning and memory of the rats were tested by Morris water maze. The mRNA levels of TNF-a, IL-1β, TGF-β1, COX-2 and iNOS were detected by real time RT-PCR, and the expressions of TNF-a, IL-1β, TGF-β1, COX-2 and iNOS proteins were examined by Western Blotting.Results:Compared to the sham-treated rats, LPS injection significantly prolonged the mean escape latency in the navigation test and shortened the adjusted escape latency, and the mRNA and protein expressions of TNF-a, IL-1β, TGF-β1, COX-2 and iNOS in hippocampus of the rats were notably increased. However, NDP treatments significantly decreased the mRNA and proteins expressions of TNF-α, IL-1β, TGF-β1, COX-2 and iNOS.Conclusion:NDP can attenuate the ability of spatial learning and memory deficits induced by LPS, which may be due to decreases of the mRNA and protein expressions of TNF-α,IL-1β,TGF-β1,iNOS and COX-2.