Anti-inflammatory Effects Of Lycium Barbarum Ploysaccharides In Lipopolysaccharide-induced BV2Microglia Cell

Lycium barbarum, a chinese traditional medicine, has been used as a food supplement forcenturies. Polysaccharides (LBPs) are the major active ingredients in Lycium barbarum.Previous studies showed that Lycium barbarum benefits eye-protective, immunoregulation[2]，anti-aging[3]and anti-tumor properties. However, the effect of LBPs in CNS are poorlyunderstood. The present study aimed to investigate the inhibitory effects of LBPs onproduction of lipopolysaccharide (LPS)–induced pro-inflammatory mediators in BV2microglia. Our data showed that LPS induced the activation of NFκB and its upstreamCASPASE3and upregulated the expression of another apoptosis-inducing factor, HSP60inBV2microglia cells and increased the release of TNF-α and HSP60in culture media. AfterLBPs treatment, activated NFκB and CASPASE3were significantly suppressed. Theenhanced expression of HSP60was reduced and LPS induced release of TNF-α and HSP60were inhibited. These results suggest that LBPs may offer substantial therapeutic potential fortreatment of neurodegenerative diseases that are accompanied by microglia activation.Objective:We aimed to investigate the neuroprotective effects of LBPs as well as the underlyingmechanisms by focusing on inflammatory response. It was possible that we could offer a cluefor treatment of neurodegenerative diseases.Methods:BV2microglia cell were treated with indicated concentration of of LBPs. We investigated the effect of LBPs on viability of LPS-stimulated BV2microglia by MTT assay. Using thewestern blot，we studied that Effects of LBPs on NF-κB, CASPASE3and HSP60proteinexpression in LPS-stimulated BV2microglia. Finally，we investigated Effects of LBPs on therelease of TNF-α and HSP60in LPS-stimulated BV2microglia.Results:1、 MTT assay demonstrated that treatment of BV2microglia with24h of exposure to LPSdecreased the viability of LPS-stimulated BV2microglia (P＜0.05). however，treatment ofmicroglia with LBPs(200-800ug/ml) for up to24h could significantly increase the viability ofLPS-stimulate BV2microglia in compared with LPS only （P＜0.05）. These resultssuggested LBPs may have a positive effect on viability of LPS-stimulated BV2microglia.2、 Western blot assay suggested that treatment of microglia with200ng/mL LPS for up to24h increased expression of CASPASE3，HSP60，NF-κB（P＜0.05）. however，LBPs couldsignificantly increase the expression of CASPASE3，HSP60，NF-κB in compared with LPSonly（P＜0.05）. Our results indicated the anti-inflammatory effects of LBPs may beassociated with inhibition of NF-κB signaling cascade.3、Using ELISA (Enzyme-linked immunosorbent assay)，LPS alone (200ng/ml) markedlyinduced the release of TNF-α and HSP60compared to control（P＜0.05）. however，LBPssignificantly reduced HSP60production induced by LPS（P＜0.05）. In summary, theseresults suggested LBPs could inhibit the release of TNF-α and HSP60in LPS-stimulated BV2microglia.Conclusion:1、 LBPs may have a positive effect on viability of LPS-stimulated BV2microglia.2、 LBPs significantly inhibited the expression of NF-κB, CASPASE3and HSP60. theseresults suggested that the anti-inflammatory effects of LBPs may be associated with inhibition of NF-κB signaling cascade.3、 LBPs effectively suppressed the production of TNF-α and HSP60in over-activatedmicroglia.