Objective:To explore the molecular mechanisms of isoliquiritigenin in stabilizing atherosclerotic plaques by activating PPAR-γsignal pathway to regulate ox-LDL metabolism.Methods:The ApoE-/-mice AS carotid plaque mod...Objective:To explore the molecular mechanisms of isoliquiritigenin in stabilizing atherosclerotic plaques by activating PPAR-γsignal pathway to regulate ox-LDL metabolism.Methods:The ApoE-/-mice AS carotid plaque model was prepared by using high fat diet and right perivascular carotid collar placement(PCCP).ApoE-/-mice were randomly divided into the model group and the isoliquiritigenin group after PCCP.C57BL/6J mice were used for the control group.High fat diet continued feeding for 8 weeks after PCCP to establish the AS model.Automatic biochemical analyzer was used to test levels of total cholesterol(TC),triacylglyceride(TG),low-density lipoprotein cholesterol(LDL-C)and high-density lipoprotein cholesterol(HDL-C).ELISA was used to measure oxidized low-density lipoprotein(ox-LDL)in serum.Hematoxylin-eosin(HE)staining was used to observe the pathological pattern of the carotid artery,and then calculated the carotid parameters.Oil red O staining was used for lipid determination,Masson staining was used to determine collagen content,MOMA-2 andα-SMA immunohistochemical staining were used to determine macrophages and smooth muscle cells,and to calculate the vulnerability index.Western blot was used to detected the expression of PPAR-γ,LXR-α,FABP-4,MMP-2 and MMP-9 in mice arteries.Results:Compared with the normal group,TC、TG、LDL-C、HDL-C and ox-LDL were increased in the model group.Compared with the model group,TC、TG、LDL-C and ox-LDL were reduced,and there was no significant change in HDL-C of the isoliquiritigenin group.Compared with the normal group,intima thickness(IT),intima/media thickness(IT/MT),plaque area(PA),and plaque area/lumen area(PA/LA)of carotid arteries were increased,the content of lipid and MOMA-2 in plaques was increased,collagen andα-SMA content decreased,and the vulnerability index was higher in the model group.The expression of PPAR-γand LXR-αwere reduced and the expression of FABP-4,MMP-2 and MMP-9 were increased in the model group.Compared with the model group,carotid IT,IT/MT,PA,and PA/LA were reduced,the content of lipid and MOMA-2 in plaques was decreased,collagen andα-SMA content were increased,and the vulnerability index was decreased in the isoliquiritigenin group.PPAR-γand LXR-αexpression were increased,FABP-4,MMP-2 and MMP-9 expression were decreased significantly in the isoliquiritigenin group.Conclusion:Isoliquiritigenin can exert anti-AS effects by activating PPAR-γ,up-regulating LXR-α,reducing FABP-4 expression,reducing ox-LDL,reducing the protein expression of MMP-2 and MMP-9,decreasing plaque vulnerability index,and increasing plaque stability.展开更多
基金National Natural Science Foundation of China(No.82274488,81874446)。
文摘Objective:To explore the molecular mechanisms of isoliquiritigenin in stabilizing atherosclerotic plaques by activating PPAR-γsignal pathway to regulate ox-LDL metabolism.Methods:The ApoE-/-mice AS carotid plaque model was prepared by using high fat diet and right perivascular carotid collar placement(PCCP).ApoE-/-mice were randomly divided into the model group and the isoliquiritigenin group after PCCP.C57BL/6J mice were used for the control group.High fat diet continued feeding for 8 weeks after PCCP to establish the AS model.Automatic biochemical analyzer was used to test levels of total cholesterol(TC),triacylglyceride(TG),low-density lipoprotein cholesterol(LDL-C)and high-density lipoprotein cholesterol(HDL-C).ELISA was used to measure oxidized low-density lipoprotein(ox-LDL)in serum.Hematoxylin-eosin(HE)staining was used to observe the pathological pattern of the carotid artery,and then calculated the carotid parameters.Oil red O staining was used for lipid determination,Masson staining was used to determine collagen content,MOMA-2 andα-SMA immunohistochemical staining were used to determine macrophages and smooth muscle cells,and to calculate the vulnerability index.Western blot was used to detected the expression of PPAR-γ,LXR-α,FABP-4,MMP-2 and MMP-9 in mice arteries.Results:Compared with the normal group,TC、TG、LDL-C、HDL-C and ox-LDL were increased in the model group.Compared with the model group,TC、TG、LDL-C and ox-LDL were reduced,and there was no significant change in HDL-C of the isoliquiritigenin group.Compared with the normal group,intima thickness(IT),intima/media thickness(IT/MT),plaque area(PA),and plaque area/lumen area(PA/LA)of carotid arteries were increased,the content of lipid and MOMA-2 in plaques was increased,collagen andα-SMA content decreased,and the vulnerability index was higher in the model group.The expression of PPAR-γand LXR-αwere reduced and the expression of FABP-4,MMP-2 and MMP-9 were increased in the model group.Compared with the model group,carotid IT,IT/MT,PA,and PA/LA were reduced,the content of lipid and MOMA-2 in plaques was decreased,collagen andα-SMA content were increased,and the vulnerability index was decreased in the isoliquiritigenin group.PPAR-γand LXR-αexpression were increased,FABP-4,MMP-2 and MMP-9 expression were decreased significantly in the isoliquiritigenin group.Conclusion:Isoliquiritigenin can exert anti-AS effects by activating PPAR-γ,up-regulating LXR-α,reducing FABP-4 expression,reducing ox-LDL,reducing the protein expression of MMP-2 and MMP-9,decreasing plaque vulnerability index,and increasing plaque stability.
