ABSTRACT
Pulmonary hypertension(PH)is a chronic,progressive,high-mortality disease characterized by a continuous increase in pulmonary vascular pressure. All types of PH have the same characteristics,i.e.,the excessive proliferation,anti-apoptosis and inflammation of pulmonary artery endothelial cells and smooth muscle cells,which leads to progressive thickening of pulmonary small vessels,resulting in pulmonary vascular remodeling and increased pulmonary vascular resistance,ultimately leading to right ventricular hypertrophy,heart failure,and death. The drugs used to treat PH mainly include L-type calcium channel blockers,phosphodiesterase 5 inhibitors,guanosine cyclase activators,endothelin receptor antagonists,and synthetic prostacyclin and its analogues. These drugs reduce pulmonary artery pressure by relaxing pulmonary blood vessels but do not cure the patient,and their prognosis remains poor. Therefore,the development of drugs that can effectively improve or even reverse pulmonary vascular remodeling is the key to treating PH. In recent years,studies on pulmonary vascular remodeling mainly included(1)the synthesis of new small-molecule compounds;(2)the transformation of mature drugs,such as the use of drug combinations and dosage form transformation,etc.;(3)the pharmacodynamic evaluation of traditional Chinese medicines and derived compounds based on the theory of "lung distension";(4)research into monomers of traditional Chinese medicine; and(5)research into new targets.
ABSTRACT
Objective:To investigate the effects of notoginsenoside R1 （NR1） on the proliferation of mice aortic smooth muscle cells （MOVAS cells） induced by angiotensinⅡ （AngⅡ） and the signal pathway of angiotensin Ⅱ type 1 receptor （AT1R） / mitogen activated protein kinases （MAPKs）. Methods:The proliferation of MOVAS cells was detected by BrdU method after AngⅡ induction. Western blot was used to detect the expression of the two main receptors of AngⅡ （AT1R and AT2R） and MAPKs pathway related proteins （ERK， p38， and JNK）. Results:（1） AngⅡ （5 μmol/L） could promote the proliferation of MOVAS cells （P<0.01）. NR1 （50 μmol/L） could inhibit the proliferation of MOVAS cells induced by AngⅡ （P<0.01）. There was no significant difference between control group and NR1 group （P>0.05）. （2） Compared with AngⅡ group， the expression of AT1R protein in AngⅡ+ NR1 group was significantly lower （P<0.05）， but there was no difference in the expression of AT2R protein （P>0.05）. （3） NR1 could significantly inhibit the phosphorylation of ERK， p38 and JNK protein after AngⅡ stimulation （P<0.01）. Conclusion:NR1 can inhibit the proliferation of MOVAS cells induced by AngⅡ， which may be related to down regulating AT1R and inhibiting the activation of MAPKs.
ABSTRACT
The effects of an ethanolic extract of Angelica gigas (EAG) on the vascular smooth muscle cell (VSMC) proliferation and high-cholesterol diet-induced hypercholesterolemia and atherosclerosis were investigated. Rat aortic VSMCs were stimulated with platelet-derived growth factor-BB (25 ng/mL) for the induction of DNA synthesis and cell proliferation. EAG (1-10 microg/mL) significantly inhibited both the thymidine incorporation and cell proliferation in a concentration-dependent manner. Hypercholesterolemia was induced by feeding male New Zealand white rabbits with 0.5% cholesterol in diet for 10 weeks, during which EAG (1% in diet) was given for the final 8 weeks after 2-week induction of hypercholesterolemia. Hypercholesterolemic rabbits exhibited great increases in serum total cholesterol and low-density lipoproteins (LDL) levels, and finally severe atheromatous plaque formation covering 28.4% of the arterial walls. EAG significantly increased high-density lipoproteins (HDL), slightly decreased LDL, and potentially reduced the atheroma area to 16.6%. The results indicate that EAG attenuates atherosclerosis not only by inhibiting VASC proliferation, but also by increasing blood HDL levels. Therefore, it is suggested that EAG could be an alternative or an adjunct therapy for the improvement of hypercholesterolemia and atherosclerosis.
Subject(s)
Animals , Humans , Male , Rabbits , Rats , Angelica , Atherosclerosis , Cell Proliferation , Cholesterol , Diet , DNA , Ethanol , Hypercholesterolemia , Lipoproteins, HDL , Lipoproteins, LDL , Muscle, Smooth, Vascular , Plaque, Atherosclerotic , ThymidineABSTRACT
Objective To investigate the effects of low frequency ultrasound (LFU) on the proliferation and apoptosis of smooth muscle cells (SMCs) in rabbits with carotid atherosclerosis(CA).Methods CA models were established in 30 New Zealand rabbits using a high fat diet and air-drying.They were randomly divided into a control group and four LFU groups:group A received 0.5 W/cm~2 LFU for 5 min/d,group B 0.5 W/cm~2 for 10 min/d, group C 1 W/cm~2,5 min/d,and group D 1 W/cm~2,10 min/d.The rabbits' carotid arteries were autopsied after 20 d of the LFU treatment.The expression of PCNA and TUNEL staining were used to explore the proliferation and apopto- sis of SMCs,and the proliferation rates (PRs) and apoptosis rates (ARs) were calculated.Results Compared with the control group,the PRs in groups B,C and D were significantly lower,while the ARs in groups B,C and D were significantly higher.There was no significant difference in ARs or PRs among groups B,C and D.Con- clusion LFU can induce SMC apoptosis and inhibit SMC proliferation in rabbits with CA.
ABSTRACT
Intimal hyperplasia, an abnormal migration and proliferation of vascular smooth muscle cells with associated deposition of extracellular connective tissue matrix, is a chronic structual changes occuring in denuded arteries, arterialized vein and prosthetic bypass graft. This is one of the most important cause of vascular graft failure within the first year after operation. Certain growth factors, particularly basic fibroblast growth factor, transforming growth factor- , and platelet-derived growth factor, are believed to be the cause of the smooth muscle cell proliferation and migration. This smooth muscle cell proliferation and collagen deposition eventually produce intimal thickening with subsequent stenosis or occlusion of the vascular lumen. In order to evaluate the serial changes of injured vessel wall, aortic patch allograft was done in rat, and studied the morphological finding at 1 day, 1, 2, 6, and 8 weeks after graft. The results were summerized as follows; (1) During the early phase after graft, no significant wall changes were seen in the region of the anastomotic site except the presence of acute inflammatory cells with platelet aggregation and thrombus formation. (2) The intimal thickening was apparent by 1 week and was predominantly composed of smooth muscle cells. At the 2 weeks after graft, endothelial cells were partially regenerated to cover the patch graft, and intimal hyperplasia was composed of a mixture of smooth muscle cells and extracellular matrix, mostly collagen. (3) Six weeks after graft, prominent features were production and deposition of collagen rather than proliferation of smooth muscle cells. Reendothelialization over the thickened intima was seen at 8 weeks and the propagation of intimal hyperplasia to adjacent intima of normal vessel was also noted. In conclusion, intimal hyperplasia after vascular injury seemed to be a progressive response of the proliferation and migration of smooth muscle cells and this result might be used for further study about the suppression of intimal hyperplasia.