基于Toll样受体4/髓样分化因子88/核因子-κB通路探讨川芎嗪对ApoE-/-小鼠动脉粥样硬化的影响OA

Objective To explore the anti-inflammatory mechanism of tetramethylpyrazine(TMP)on ApoE-/-mice with atherosclerosis(AS)by inhibiting the Toll-like receptor 4(TLR4)/myeloid differentiation factor 88(MyD88)/nuclear factor kappa B(NF-κB)signaling pathway.Methods Eight male C57BL/6 mice fed with a standard chow diet were chosen as the control group.Male ApoE-/-mice were fed a high-fat diet to establish an AS model and randomly divided into two groups after weight matching:the AS group and the TMP group,8 in both group.Mice in the TMP group received intraperitoneal injections of 20 mg/mL TMP injection at a dose of 100 mg/kg.Mice in the AS and control groups were administered an equal volume of 0.9%sodium chloride solution via intraperitoneal injection.All treatments were administered once daily for three weeks.After the treatment period,blood was collected from the infraorbital vein of mice in each group.Serum was separated,and levels of high-density lipoprotein cholesterol(HDL-C)and low-density lipoprotein cholesterol(LDL-C)were measured by immunoturbidimetry.Levels of total cholesterol(TC),triglycerides(TG),tumor necrosis factor-alpha(TNF-α),interleukin-6(IL-6),and monocyte chemoattractant protein-1(MCP-1)were determined using enzyme-linked immunosorbent assay(ELISA).Aortic tissues from mice in each group were stained with SudanⅣ,Oil Red O,and hematoxylin-eosin(HE)to observe plaque formation.Reverse transcription polymerase chain reaction(RT-PCR)was used to measure the mRNA expression levels of TLR4,MyD88,inhibitor of nuclear factor κB α(IκBα),and p65 in the TLR4/MyD88/NF-κB signaling pathway in aortic tissue.Western blotting was performed to detect the protein expression levels of TLR4,MyD88,p-IκBα,IκBα,p-p65,and p65 in the same pathway.Results At both 12 and 16 weeks,there were statistically significant differences in body weight among the groups(F=7.251,27.406;P<0.01).Compared with the control group,body weights of the AS group and the TMP group were higher.The levels of TC,TG,LDL-C,TNF-α,IL-6,MCP-1,and plaque area were all statistically different among the groups(F=33.202,12.032,32.263,32.571,74.388,24.312,77.532;P<0.01).Compared with the AS group,the TMP group exhibited significantly lower levels of TNF-α,IL-6,MCP-1,and reduced AS plaque area(all P<0.05).There were statistically significant differences in the levels of TLR4 mRNA,MyD88 mRNA,IκBα mRNA,p65 mRNA,TLR4,MyD88,p-IκBα/IκBα,and p-p65/p65 in the aortic tissues in mice among the groups(F=28.603,35.433,128.014,39.052,42.532,38.911,138.314,319.327;P<0.01).Compared with the AS group,the levels of TLR4 mRNA,MyD88 mRNA,p65 mRNA,TLR4,MyD88,p-IκBα/IκBα,and p-p65/p65 in the TMP group decreased,while the level of IκBα mRNA increased(P<0.05).Conclusion Tetramethylpyrazine alleviates inflammatory response,reduces AS area,and inhibits the TLR4/MyD88/NF-κB signaling pathway in ApoE-/-mice with AS.