| Objective: In this study,through the establishment of experimental insulin resistance model of rats by feeding with atherogenic-diet,to observe the influence of Didangtang on the proliferation of G0/G1,S,G2/M,PI and apoptosis-related genes Fas,anti-apoptotic gene Bcl-2 on smooth muscle cells,to explore Didangtang in the prevention and treatment of IR for the pathology of cardiovascular and cerebrovascular diseases based on the mechanism,which could provide theoretical basis for the clinical applications.Didangtang is originated from Zhang Zhongjing,composed of rhubarb,peach kernel,Tabanus and leeches 4 herbs.It is a classical prescription to treat excessive pattern of stagnated blood with the effects of disease involving taiyang and yangming simultaneously.We use Didangtang to treat the IR rat model,discuss the mechanism and control methods of vascular smooth cells proliferation and apoptosis,providing the scientific basis for clinical use of drugs.Methods:1 35 health and clean level Wistar male rats in 180g-220 g weight were chosen and randomly divided into 5 groups: blank control group(Ⅰ),model group(Ⅱ),Didangtang low-dose group(Ⅲ),Didangtang high-dose group(Ⅳ)and Xuezhikang group(Ⅴ),respectively N = 7.2 The administration of drugs: The rats of blank control group were fed with normal diet,other groups were fed with high fat diet.Blank control group and model group every day in tragastric administrated with stilled water l0ml/kg;Didangtang low-dose group every day in tragastric administrated with Didangtang 1g crude drug/kg.d(the dose equivalent to 10 times of adult daily per kilogram of body weight);Didangtang high-dose group every day in tragastric administrated with Didangtang 2g crude drug/kg.d(the dose equiv-alent to 20 times of adult daily per kilogram of body weight);Xuezhikang group every day in tragastric administrated with Xuezhikang 0.2g/Kg.d(the dose equivalent to 10 times of adult daily per kilogram of body weight).3 Indicators: All animals were fed 8 weeks continuously,then take blood by decapitate at the end of 8th week,Serum blood lipids,FBG and INS were detected,HOMA-IR and ISI were calculated;Thoracic aorta was retained,cut off the outer membrane organization,a part in the 10% formalin fixed,paraffin section,HE staining observation of pathological;a part in the 10% in ethanol,the number of cells in proliferation cycle and proliferation index was detected by flow cytometry,apoptotic-related genes Fas and Bcl-2 were detected by Immunohistochemical SP method.Results:1 Effect of Didangtang on ISI and HOMA-IR of the IR ratCompared with blank control group,the model group’s ISI was statistically decreased(P<0.05),HOMA-IR was increased(P<0.01).Compared with model group,ISI was significantly higher,HOMA-IR was significantly reduced in rats of low and high dose groups(P<0.01);Low group compared with high group,was a trendency that the effect in low dose group was better than that in high group,but without statistical differance;Compared with Xuezhikang group,there were no statistical significance in low and high dose groups.Which indicated that Didangtang can increase insulin sensitivity,improve insulin resistance.2 Effect of Didangtang on blood lipids of the IR ratCompared with control group,TC,TG,LDL-C were increased(P<0.01),while HDL-C was decreased obviously in model group(P<0.01);Compared with model group,TC,TG,LDL-C were decreased(P<0.01 or P<0.05),while HDL-C was increased obviously in low-dose group(P<0.01);Compared with model group,TC,TG,LDL-C were decreased obviously(P<0.01),while HDL-C was increased in high-dose group(P<0.01);Compared high-dose group with low-dose group,there was a trendency that the effect in high dose group was better than that in low group,but has no statistical significance;Co-mpared low-dose with Xuezhikang group,has no statistical significance.Compared high-dose group with Xuezhikang group,TC was decreased P<0.05),TG,LDL-C were decreased more than Xuezhikang group,but there was no statistical significance.HDL-C was increased(P<0.05).3 Effect of Didangtang on aorta smooth muscle cells proliferation cycle of the IR ratCompared with blank control group,the proportion of G0/G1 stage decreased,that of S and G2/M stage increased in model group,PI increased(P<0.01);The low dose group’s proportion of G0/G1 stage increased(P<0.05),S stage decreased(P<0.01),G2/M stage has the tendency of decreasing,but without statistical difference;The proportion of G0/G1 stage increased,and that of S and G2/M decreased,PI decreased,which in high dose group(P<0.01).Low group compared with high group,was a trendency that th the effect in high dose group was better than that in low group,but without statistical differance;Compared with Xuezhikang group,the low and high dose groups’ data,has no statistical significance.Which indicated that Didangtang can reduce PI,thus inhibit the proliferation of smooth muscle cells.4 Effect of Didangtang to the expression of Fas and Bcl-2 in the aorta smooth musle cellsCompared with blank control group,model group’s Fas gene expression decreased significantly,with statistically significant(P<0.01),the expression of Bcl-2 gene was increased,with statistically significant(P<0.05);Compared with model group,Fas gene increased,while Bcl-2 gene was significantly reduced in rats of low and high dose groups,statistics learn significant difference(P<0.01);Low group compared with high group,was a trendency that the effect in high dose group was better than that in low group,but without statistical differance;Compared with Xuezhikang group,there were no statistical significance in low and high dose groups(P>0.05).Which indicated that Didangtang can increase the expression of Fas,reduce Bcl-2,thus promote the apoptosis of smooth muscle cells.5 Aortic pathologyBlank group: aortic intima have complete endothelial,which continuous smooth,lower with a small amount of loose connective tissue.Membrane in the direction is clear,smooth muscle without hyperplasia;Elastic fiber is no exception;Model group: endometrial thickening,obviously visible endothelial intima layer has accumulated inflammatory cells,endothelial incomplete,discontinuous surface is not smooth,the surface of the ups and downs,endothelial lower obvious thickening,disordered arrangement of a large number of smooth muscle fibers,elastic fiber fracture and dislocation in the membrane,smooth muscle hyperplasia.The low-dose group: endometrial endothelium intact,no inflammatory cells but uneven surface slightly rise and fall,endothelial lower slightly thick,a small amount of smooth muscle,elastic fiber arrangement not seen obvious abnormity,slightly thick membrane in smooth muscle,part of the elastic fiber corrugated fracture.The high dose group: full continuous lining endothelial,smooth surface,the surface of endothelial no inflammatory cells,endothelial lower layer is very thin,not seen obvious hyperplasia of elastic fibers and smooth muscle;Homogeneous and the thickness of membrane smooth muscle hyperplasia is not obvious.Xuezhikang group: visible endothelial integrity,endothelial lower layer is very thin,not seen obvious hyperplasia of elastic fibers and smooth muscle.Membrane smooth muscle in the direction is clear,uniform thickness,hyperplasia is not obvious.Conclusions:1 IR rat model was successfully established by feeding high fat diet,which proved that high fat diet can induce IR.2 Didangtang could increase ISI,decrease HOMA-IR,which indicated that Didangtang can increase insulin sensitivity,improve insulin resistance.3 Didangtang could decrease TC,TG and LDL,increase HDL,which indicated that Didangtang can regulate blood lipid,improve insulin resistance.4 Didangtang could decrease PI,indicating that Didangtang can inhibit the proliferation of vascular smooth muscle cells.5 Didangtang could increase Fas gene,decrease Bcl-2 gene,shows that Didangtang can promote the apoptosis of vascular smooth muscle cells. |
PDF Full Text Request