Aim To elucidate whether Astragaloside Ⅳcould ameliorate pathological myocardial hypertrophy and fibrosis via the EGR1-SIRT1-PPARα-SCAD signa-ling pathway in TAC mice.Methods After randomi-zing mice into groups,the Sham+AS-Ⅳ group and TAC+AS-Ⅳ group were intragastrically administered 20 mg·kg-1AS-Ⅳ once daily,whereas the Sham+NS group and TAC+NS group were given equivalent saline.Six weeks post-surgery,an evaluation of cardiac function was conducted,heart weight index was compu-ted,morphological alterations in heart were noted,vari-ations in collagen and myocardial hypertrophy indexes were analyzed,ATP content,free fatty acid content,hydroxyproline content,SCAD expression,and enzyme activity were measured,and an initial investigation into the protein expression of EGR1-SIRT1-PPARα-SCAD in myocardial tissues was undertaken.Results After AS-Ⅳ intervention,the heart weight index of TAC mice decreased(P＜0.01),LVAWd,LVAWs,LVPWd and LVPWs values decreased(P＜0.01,P＜0.05),EF％and FS％values increased(all P＜0.01),myocardial hypertrophy markers and collagen area decreased,FFA content,HYP content and collagen expression de-creased(all P＜0.01),SCAD enzyme activity and ex-pression increased(P＜0.01,P＜0.05),and ATP content increased(P＜0.01).The expression of EGR1 protein decreased,and the expression of SIRT1 and PPARα protein increased(all P＜0.01).Conclu-sions AS-Ⅳ may improve fatty acid oxidation via the EGR1-SIRT1-PPARα-SCAD signaling pathway,thereby ameliorating pathological myocardial hypertrophy and fibrosis in TAC model mice.

Aim To elucidate whether Astragaloside Ⅳcould ameliorate pathological myocardial hypertrophy and fibrosis via the EGR1-SIRT1-PPARα-SCAD signa-ling pathway in TAC mice.Methods After randomi-zing mice into groups,the Sham+AS-Ⅳ group and TAC+AS-Ⅳ group were intragastrically administered 20 mg·kg-1AS-Ⅳ once daily,whereas the Sham+NS group and TAC+NS group were given equivalent saline.Six weeks post-surgery,an evaluation of cardiac function was conducted,heart weight index was compu-ted,morphological alterations in heart were noted,vari-ations in collagen and myocardial hypertrophy indexes were analyzed,ATP content,free fatty acid content,hydroxyproline content,SCAD expression,and enzyme activity were measured,and an initial investigation into the protein expression of EGR1-SIRT1-PPARα-SCAD in myocardial tissues was undertaken.Results After AS-Ⅳ intervention,the heart weight index of TAC mice decreased(P＜0.01),LVAWd,LVAWs,LVPWd and LVPWs values decreased(P＜0.01,P＜0.05),EF％and FS％values increased(all P＜0.01),myocardial hypertrophy markers and collagen area decreased,FFA content,HYP content and collagen expression de-creased(all P＜0.01),SCAD enzyme activity and ex-pression increased(P＜0.01,P＜0.05),and ATP content increased(P＜0.01).The expression of EGR1 protein decreased,and the expression of SIRT1 and PPARα protein increased(all P＜0.01).Conclu-sions AS-Ⅳ may improve fatty acid oxidation via the EGR1-SIRT1-PPARα-SCAD signaling pathway,thereby ameliorating pathological myocardial hypertrophy and fibrosis in TAC model mice.

AIM:To investigate the changes of short-chain acyl-CoA dehydrogenase(SCAD)in hypertensive vascular remodeling and to explore the relationship between SCAD and vascular remodeling in hypertension.METHODS:The spontaneously hypertensive rats(SHR;24 weeks old)and Wistar rats(24 weeks old)were used as experimental con-trol groups.The SHR and Wistar rats of 16 weeks old were trained by swimming as experimental groups.The systolic pres-sure was measured periodically.The thickness of vascular wall and the diameter of the vascular lumen were measured.The contents of ROS and ATP,the enzyme activity of SCAD, and the expression of SCAD at mRNA and protein levels in the aorta were determined.The free fatty acid in the serum and aorta was also measured.RESULTS:Compared with Wistar group,the diameter of vascular lumen decreased in SHR group.The thickness of vascular wall,the ratio of vascular wall and the diameter of vascular lumen,and the blood pressure in SHR group were increased significantly(P<0.05).Com-pared with SHR group,the diameter of vascular lumen increased in SHR +swim group.The thickness of vascular wall,the ratio of vascular wall and the diameter of vascular lumen,and the blood pressure in SHR +swim group were decreased sig-nificantly.Compared with control group, the expression of SCAD at mRNA and protein levels, the enzyme activity of SCAD,and the content of ATP were decreased in SHR group.However,the free fatty acid in the serum and aorta,and the content of ROS in the aorta were increased in SHR group.The expression of SCAD at mRNA and protein levels,the en-zyme activity of SCAD,the content of ATP were increased in Wistar +swim group and SHR +swim group.However, the free fatty acid in serum and aorta,and the content of ROS in the aorta were decreased in Wistar +swim group and SHR+swim group.CONCLUSION: Decrease in SCAD expression may be associated with hypertensive vascular remodeling. Swimming training can reverse hypertensive vascular remodeling by increasing the expression of SCAD in the aorta.