Effect Of Fuxinyixian Decoction On Myocardial Fibrosis After Myocardial Infarction Through Shh Signal Pathway

Objective:To investigate the possible mechanism of improving myocardial fibrosis and cardiac function after myocardial infarction by studying the effect of Fuxinyixian Decoction on Shh signaling pathway in myocardial tissues of rats with myocardial infarction.Methods:Seventy SPF grade male rats,aged 6 weeks,with a body mass of(200 ± 20)g,were randomly extracted to establish a myocardial infarction model by ligating the left anterior descending branch of the coronary artery.The remaining 10 rats were used as a sham operation group,with only threading and no ligation.The standard for determining the success of myocardial infarction modeling was the elevation of the ST segment in lead II of the electrocardiogram for more than 15 minutes.The rats successfully modeled were randomly divided into 5 groups: model group,rosuvastatin group,low dose Fuxinyixian Decoction group,medium dose Fuxinyixian Decoction group,and high dose Fuxinyixian Decoction group,with 10 rats in each group.The rosuvastatin group was given 2 mg/kg by gavage,the low dose group of Fuxinyixian Decoction was given 0.7 g/kg by gavage,the medium dose group of Fuxinyixian Decoction was given 1.4 g/kg by gavage,the high dose group of Fuxinyixian Decoction was given 2.8 g/kg by gavage,and the sham operation group and model group were given equal volume of physiological saline by gavage once a day for 8 consecutive weeks.During this period,the general condition of the rats was observed.After treatment,rats were anesthetized and their cardiac function was measured by ultrasound and left ventricular end diastolic internal diameter(LVIDD),left ventricular end systolic internal diameter(LVISD),left ventricular fraction shortening(LVFS),and left ventricular ejection fraction(LVEF)were measured.After ultrasound,the rats were killed,and cardiac tissue was removed.Hematoxylin eosin(HE)staining was used to observe the morphological changes of myocardial tissue,and Masson staining was used to observe the area of myocardial fibrosis;The changes of Shh,Ptc1,Gli1 and α-SMA protein expression levels were detected by Western blot;The changes of Shh,Ptc1,Gli1 and α-SMA m RNA expression levels in myocardial tissues were detected by RTPCR.Results:1.Changes in cardiac function of rats in each group: Compared with the sham operation group,LVIDD and LVISD in the model group increased,while LVEF and LVFS decreased(P < 0.01);Compared with the model group,LVIDD and LVISD in the rosuvastatin group and the low,medium,and high dose groups of Fuxinyixian Decoction decreased,while LVEF and LVFS increased(P < 0.01).The degree of improvement of heart function in each treatment group from high to low were as follows: the high dose group of Fuxinyixian Decoction > the medium dose group of Fuxinyixian Decoction > rosuvastatin group > the low dose group of Fuxinyixian Decoction.2.Morphological changes of myocardial tissue of rats in each group: After HE staining,under the light microscope,it was found that compared with the sham operation group,the arrangement of myocardial fibers in the model group is extremely irregular,with significant myocardial fiber breakage,and significant disorder in the structure of myocardial cells,with a large number of inflammatory cell infiltration visible;Compared with the model group,in the rosuvastatin group and the low,medium,and high dose groups of Fuxinyixian Decoction significantly increased the alignment of myocardial fibers,reduced the rupture of myocardial fibers,increased the structural integrity of myocardial cells,and reduced the infiltration of inflammatory cells.The improvement degree of each treatment group from high to low were as follows: the high dose group of Fuxinyixian Decoction > the medium dose group of Fuxinyixian Decoction > rosuvastatin group > the low dose group of Fuxinyixian Decoction.3.Changes in myocardial fibrosis area of rats in each group: After Masson staining,it was observed under the light microscope that compared with the sham operation group,large areas of blue staining were visible in the myocardial tissue of the model group,showing myocardial fibrosis changes,with a significant increase in the area of fibrosis(P < 0.01);Compared with the model group,the blue staining area of myocardial tissue in the rosuvastatin group and the low,medium,and high dose groups of Fuxinyixian Decoction significantly decreased,and the degree of fibrosis was reduced(P < 0.01).The degree of improvement of myocardial fibrosis in each treatment group ranged from high to low as follows: the high dose group of Fuxinyixian Decoction > the medium dose group of Fuxinyixian Decoction > rosuvastatin group>the low dose group of Fuxinyixian Decoction.4.Changes in α-SMA expression and Shh,Gli1,Ptc1 protein expression in myocardial tissue of rats in each group: Compared with the sham operation group,in the myocardial tissue of the model group α-SMA,Shh,Gli1,and Ptc1 significantly increased(P < 0.01,P < 0.05).Compared with the model group,the myocardial tissue of the rosuvastatin group,the Fuxinyixian Decoction medium and high dose groups α-SMA and Shh protein decreased(P < 0.01,P < 0.05),while Gli1 and Ptc1 protein in myocardial tissue decreased(P < 0.01,P < 0.05)in the rosuvastatin group,low,medium,and high dose groups of Fuxinyixian Decoction.The degree of reduction in each treatment group from high to low were as follows: the high dose group of Fuxinyixian Decoction > the medium dose group of Fuxinyixian Decoction >rosuvastatin group> the low dose group of Fuxinyixian Decoction.5.Changes in α-SMA m RNA expression and Shh,Gli1,Ptc1 m RNA expression in the myocardial tissue of the model group α-SMA,Shh,Gli1,and Ptc1 m RNA significantly increased(P < 0.01).Compared with the model group,in the myocardial tissue of the rosuvastatin group and the low,medium,and high dose groups of Fuxinyixian Decoction α-SMA,Shh,Gli1,and Ptc1 m RNA significantly increased(P< 0.01).The degree of reduction in each treatment group ranged from high to low were as follows: the high dose group of Fuxinyixian Decoction > the medium dose group of Fuxinyixian Decoction > rosuvastatin group> the low dose group of Fuxinyixian Decoction.Conclusions:1.Fuxinyixian Decoction had the effect of reducing LVIDD and LVISD,increasing LVEF and LVFS,improved cardiac function,reduced inflammatory cell infiltration in myocardial tissue,and improved myocardial fibrosis in rats after myocardial infarction.The high dose group of Fuxinyixian Decoction had the best effect.2.Fuxinyixian Decoction could reduce α-SMA and Shh,Gli1,Ptc1 protein and m RNA expression levels.The high dose group of Fuxinyixian Decoction had the best effect.3.Fuxinyixian Decoction protected cardiac function,improved myocardial fibrosis,and reduced α-SMA expression may be related to downregulation of Shh signaling pathway.