| Background and purpose:Sjogren's syndrome(SS)is an autoimmune systemic chronic progressive disease.The inflammatory response caused by macrophage injury plays a key role in the development of Sjogren's syndrome.Macrophages has an important role in the context of the innate immune system,activation of macrophages can not only through the synthesis of reactive oxygen species(ROS)and reactive nitrogen material(RNS)kill microorganisms,and the ability to secrete a series of related factors,to immunity and inflammation have a vital role,and the damage caused by excessive activation of the body's inflammatory reaction process and the degree of tissue damage has very important influence.The mechanism may be that by inhibiting the activation of TLR4/MyD88/NF-?B signaling pathway and NLRP3 inflammatory bodies,Ophiopogon japonicus polysaccharide reduces the oxidative stress response and macrophage apoptosis,thereby reducing the macrophage injury and secretion of inflammatory factors.In this study,a Lipopolysaccharide(LPS)induced injury model of macrophages(RAW264.7)was established in vitro to observe the protective effect of Ophiopogon japonicus polysaccharide on its injury,and to further explore its possible mechanism.Methods:In vitro culture of RAW264.7,cells were treated with different concentrations of LPS(0,1,2,4,8,16,32,64,128ug/ml)and Ophiopogon japonicus polysaccharide(0,5,10,50,100,500,1000ug/ml)for 6h and 24h respectively.Cell counting kit-8(CCK8)was used to screen the appropriate molding agent and drug concentration.The contents of IL-1?,IL-6 and TNF-? in the supernatant were detected by ELISA,the activity of superoxide dismutase(SOD)and the content of lipid peroxides(MDA)were detected by the kit,and the expression of related proteins in NF-?B signaling pathway and NLRP3 inflammatory bodies signaling pathway were detected by Western Blot.Results:When the concentration of LPS was 8ug/ml,the activity of macrophages significantly decreased,while each dose of Ophiopogon japonicus polysaccharide had no significant effect on the activity of macrophages.Therefore,in this study,8ug/ml LPS was selected as the concentration of molding agent,and 50,100 and 500ug/ml as low,medium and high doses of Ophiopogon japonicus polysaccharide;Compared with the blank control group,IL-1?,IL-6,TNF-? and MDA levels in the supernatant of the model group increased significantly,and SOD activity decreased significantly.In the model group,the expression levels of TLR4,MyD88 and the phosphorylation levels of I?B? and p65 increased significantly,and the expression levels of I?B? protein decreased significantly.In the model group,the expression levels of NLRP3,ASC,Caspase-1 and IL-1? all increased significantly,while the expression levels of Bcl-2 decreased significantly;After pretreatment with low,medium and high dose concentrations of Ophiopogon japonicus polysaccharide,macrophage viability increased in each dose group of Ophiopogon japonicus polysaccharide,and the expression levels of IL-1?,IL-6,TNF-? in the supernatant decreased significantly.MDA expression levels decreased significantly,SOD expression levels increased,I?Ba expression levels increased,TLR4,MyD88 expression,and I?B?,p65 phosphorylation levels decreased;NLRP3,ASC,Caspase-1,IL-1? in each dose group of Ophiopogon japonicus polysaccharide protein expression level decreased significantly,Bcl-2 protein expression level increased significantly.Conclusion:Ophiopogon japonicus polysaccharide have a good protective effect on macrophages,can improve the viability of macrophages,reduce the expression of IL-1?,IL-6,TNF-? and MDA in macrophages,increase the expression of SOD in macrophages;The mechanism may be through inhibiting TLR4/MyD88/NF-?B-related signaling pathways and activation of NLRP3 inflammatory bodies,reducing oxidative stress and macrophage apoptosis,thereby reducing macrophage damage and inflammatory factors secretion. |
PDF Full Text Request