Berberine Inhibits Mechanical Stretch Stress induced MAPK Phosphorylation，Proliferation and Migration of Vascular Smooth Muscle Cells / 中山大学学报(医学科学版)

@#【Objective】To observe whether berberine can inhibit vascular smooth muscle cells（VSMC）proliferation induced by mechanical strength stress and to investigate the role of MAPK pathway in it.【Methods】The cultured VSMC were divided into 4 groups：negative control group（NC group），stretch stress group（SS group），berberine pretreated and stretch stress stimulation group（BBR+SS group），and berberine group. In NC group，phosphate buffer saline was used as a negative control；in SS group，stretch stress was given to VSMC；in BBR+SS group，VSMC were pretreated with berberine for 1 hour and then exposed to stretch stress；in BBR group，VSMC were treated only with berberine for 1 hour and cultured in serum- free DMEM afterwards. We collected VSMC in each group ，detected and analyzed their MAPK phosphorylation，proliferation and migration by using Western blotting，immunofluorescence and wound-healing assay respectively. 【Results】 Compare with NC group，stretch stress markedly induced VSMC proliferation and migration ，which could be inhibited significantly by berberine. Stretch stress obviously increased phosphorylation of MAPK （ERK，JNK，p38），which could be inhibited by berberine in a concentration dependent manner. 【Conclusion】 Berberine inhibits hypertension-induced proliferation and migration of VSMC through MAPK pathway. The results revealed the new use and mechanism of berberine，and provided important data for further study on the prevention and treatment of vascular remodeling caused by abnormal increase of mechanical stress in hypertension.

Effect of alisol A 24-acetate on proliferation of aorta smooth muscle cells in rats induced by ox-LDL / 中国中药杂志

Alisol A 24-acetate, a triterpenoid extracted from Alisma orientale, has shown anti-atherosclerotic actions and many studies have proved that oxidized low density lipoprotein (Ox-LDL) could promote proliferation of aorta smooth muscle cells (VSMCs) which are closely related to atherosclerosis (AS). The purpose of this study was to evaluate the effect of alisol A 24-acetate on the proliferation of VSMCs isolated from the thoracic aorta of rats induced by ox-LDL. VSMCs were induced by ox-LDL(50 mg·L⁻¹) to establish the proliferation model and intervened by alisol A 24-acetate (5, 10, 20 mg·L⁻¹) for 12, 24 and 48 h. Then the proliferation of VSMCs was detected by MTT assay; protein expression levels of VSMCs PCNA, cyclinD1, cyclinE, p21, p27 and VSMCs PCNA, p21and p27 mRNA expression levels were detected by Western blot and Real-time polymerase chain reaction (RT-PCR) respectively. The results showed that ox-LDL could induce the proliferation of VSMCs (<0.05), increase the protein expression levels of PCNA, cyclinD1 and cyclinE in the VSMCs (<0.05) and inhibit the protein and mRNA expression levels of p21 and p27 (<0.05). As compared with the model group, alisol A 24-acetate inhibited the proliferation of VSMCs in rats induced by ox-LDL and inhibited the protein expression of VSMCs PCNA, cyclinD1, cyclinE and enhanced the protein and mRNA p21 and p27 expression levels (<0.05). The effect was more obvious with the increase of concentration of alisol A 24-acetate. These data indicate that alisol A 24-acetate can inhibit the proliferation of VSMCs induced by ox-LDL and the mechanism may be associated with inhibiting expression of cyclin protein, including cyclinD1, cyclinE, p21, p27 and so on.

The Regulation of MiR-143/145 on Akt Signaling during VSMC Phenotype Switching in Exercise-induced Hypertensive Arteries / 中国运动医学杂志

Objective To explore the effect of exercise on vascular smooth muscle cell(VSMC) phenotype switching in hypertensive arteries and to figure out the regulatory mechanisms of mircroRNA (miR)-143/145 on Akt signaling during the process.Methods Three-month old(Wistar Kyoto rats) WKY and (spontaneously hypertensive rats) SHR were divided into 4 groups:WKY-C,SHR-C,WKY-E,and SHR-E,which were subjected to 8wk moderate treadmill training (E) or sedentary as control (C) with blood pressure being monitored.After the last bout of exercise,mesenteric arteries were isolated to determine VSMC phenotypic marker,miR143/145 expression and Akt phosphorylation.In transfection experiment in vitro,miR-145 mimic and miR-145 inhibitor were transfected into cultured VSMC,and given immunofluorescent staining using α-actin to detect the cell morphology.VSMC phenotype marker,Akt phosphorylation,and mRNA expressions of the insulin-like growth factor Ⅰ receptor (IGF-IR),Insulin receptor substrate 1 antibody(IRS-1),and p70S6K were determined.Results The blood pressure of SHR-E reduced significantly compared with that of SHR-C(P＜0.05),and the arterial thicknessof SHR-E decreased significantly (P＜0.05).The VSMC contractile marker calponin in SHR-E increased significantly when compared with SHR-C(P＜0.05),while the proliferative marker osteoppontin (OPN) in SHR-E reduced significantly than that in SHR-C(P＜0.05).The miR-145 of SHR-E was significantly enhanced(P＜0.05),while there was no significant difference in the miR-143.The Akt of SHR-E was activated more significantly than SHR-C(P＜0.05).The miR-145 overexpression by transfecting miR-145 mimic into VSMC increased α-actin significantly(P＜0.05),while miR-145 inhibitor made α-actin a decrease.Akt activation was significantly inhibited by miR-145 mimic and enhanced by miR-145 inhibitor(P＜0.05).The miR-145 significantly inhibited IRS-1 and IGF-1R mRNA(P＜ 0.05),but the targeting effects were not significant on p70S6K mRNA.Conclusions Exercise ameliorates the high blood pressure and remodels arterioles,which may rely on its regulatory role on VSMC switching from proliferative to contractile phenotype,and miR-145 is involved in this process.However,the Akt activation is not caused by the overexpression of miR-145,but through other means to promote the above VSMC switching.

A spleen tyrosine kinase inhibitor attenuates the proliferation and migration of vascular smooth muscle cells

BACKGROUND: Pathologic vascular smooth muscle cell (VSMC) proliferation and migration after vascular injury promotes the development of occlusive vascular disease. Therefore, an effective chemical agent to suppress aberrant proliferation and migration of VSMCs can be a potential therapeutic modality for occlusive vascular disease such as atherosclerosis and restenosis. To find an anti-proliferative chemical agent for VSMCs, we screened an in-house small molecule library, and the selected small molecule was further validated for its anti-proliferative effect on VSMCs using multiple approaches, such as cell proliferation assays, wound healing assays, transwell migration assays, and ex vivo aortic ring assay. RESULTS: Among 43 initially screened small molecule inhibitors of kinases that have no known anti-proliferative effect on VSMCs, a spleen tyrosine kinase (Syk) inhibitor (BAY61-3606) showed significant anti-proliferative effect on VSMCs. Further experiments indicated that BAY61 attenuated the VSMC proliferation in both concentration- and time-dependent manner, and it also significantly suppressed the migration of VSMCs as assessed by both wound healing assays and transwell assays. Additionally, BAY61 suppressed the sprouting of VSMCs from endothelium-removed aortic rings. CONCLUSION: The present study identified a Syk kinase inhibitor as a potent VSMC proliferation and migration inhibitor and warrants further studies to elucidate its underlying molecular mechanisms, such as its primary target, and to validate its in vivo efficacy as a therapeutic agent for restenosis and atherosclerosis.

Effects of lentivirus-mediated siRNA interference of USP39 on proliferation and migration of mice vascular smooth muscle cell / 中国生化药物杂志

Objective To investigate the effect of lentivirus-mediated siRNA interference of USP39 on proliferation and migration of mice vascular smooth muscle cell in vitro.Methods Five siRNAs of siControl, siRNAUSP39-70, siRNAUSP39-71, siRNAUSP39-72 and siRNAUSP39-73 were designed and sythezied,mice VSMCs were infected with the lentivirus for delivering siRNAUSP39-73, and the stably transfected cells were selected by puromycin.The interference efficiency of siRNAUSP39-73 was assessed with Western blot.The effect of USP39 interference on the proliferation of VSMCs was determined by cells counting and MTT assay.Transwell assay was used to detect the migration of VSMCs.Results Recombinant lentiviral vector siRNAUSP39-73 was successfully transfected into mice VSMCs.Comparing with siControl group and Normal group, USP39 protein level of siRNAUSP39-73 VSMCs were decreased(P<0.05), and the proliferation and migration ability were all inhibited(P<0.05).Conclusion Targeted down-regulation of USP39 expression can inhibit the proliferation and migration of mice VSMCs in vitro.

Effects of CurTn on proliferation of VSMC / 中国药理学通报

Aim To explore the anti-proliferation effects of curcumin trinicotinate ( CurTn ) on vascular smooth muscle cell ( VSMC ) and its mechanism. Methods The cells were cultured in DMEM supple-mented with 10% fetal bovine serum. MTT assay was used to examine cell proliferation. FCM was used to observe cell cycle. The expressions of PCNA, Cy-clinD1 and p-ERK1/2 were analyzed using Western blot. Results CurTn could inhibit the proliferation of VSMC and showed a certain amount-time relationship. What’ s more, CurTn could increase the G1 phase pro-portion of cell, decrease the S phase proportion and the expression level of PCNA protein. It was also found that CurTn significantly inhibit the protein expression of p-ERK1/2 and Cyclin D1 . Conclusion CurTn may inhibit the proliferation of VSMC via downregulating the expression of CyclinD1 and p-ERK1/2 .

Hydroxysafflor yellow A inhibits VSMCs proliferation via PCNA and MEK-ERK1/2 / 中国药理学通报

Abstrac:Aim To study the effect of hydroxysafflor yellow A ( HYSA ) on the proliferation of vascular smooth muscle cells ( VSMCs) and the related molecu-lar mechanism. Methods The inhibitory effects of hydroxysafflor yellow A on VSMC proliferation was de-tected using cell culture, MTT assay, Western blot and immunohistochemical staining. Results The results showed that HYSA inhibited cell proliferation induced by PDGF in a dose-dependent (5,10,20,40 μmol· L-1 ) manner, reduced proliferating cell nuclear anti-gen ( PCNA ) expression and blocked PDGFR-MEK-ERK1/2 signaling pathway activated by PDGF in VSMCs. Conclusion HYSA inhibits VSMCs prolifer-ation via reducing the expression of PCNA and blocking signal transduction of MEK-ERK1/2 in VSMCs.

Pitavastatin Regulates Ang II Induced Proliferation and Migration via IGFBP-5 in VSMC

Angiotensin II (Ang II), a key mediator of hypertensive, causes structural changes in the arteries (vascular remodeling), which involve alterations in cell growth, vascular smooth muscle cell (VSMC) hypertrophy. Ang II promotes fibrotic factor like IGFBP5, which mediates the profibrotic effects of Ang II in the heart and kidneys, lung and so on. The purpose of this study was to identify the signaling pathway of IGFBP5 on cell proliferation and migration of Ang II-stimulated VSMC. We have been interested in Ang II-induced IGFBP5 and were curious to determine whether a Pitavastatin would ameliorate the effects. Herein, we investigated the question of whether Ang II induced the levels of IGFBP5 protein followed by proliferation and migration in VSMC. Pretreatment with the specific Angiotensin receptor type 1 (AT1) inhibitor (Losartan), Angiotensin receptor type 2 (AT2) inhibitor (PD123319), MAPK inhibitor (U0126), ERK1/2 inhibitor (PD98059), P38 inhibitor (SB600125) and PI3K inhibitor (LY294002) resulted in significantly inhibited IGFBP5 production, proliferation, and migration in Ang II-stimulated VSMC. In addition, IGFBP5 knockdown resulted in modulation of Ang II induced proliferation and migration via IGFBP5 induction. In addition, Pitavastatin modulated Ang II induced proliferation and migration in VSMC. Taken together, our results indicated that Ang II induces IGFBP5 through AT1, ERK1/2, P38, and PI3K signaling pathways, which were inhibited by Pitavastatin. These findings may suggest that Pitavastatin has an effect on vascular disease including hypertension.

High Glucose Induces Connective Tissue Growth Factor Expression and Extracellular Matrix Accumulation in Rat Aorta Vascular Smooth Muscle Cells Via Extracellular Signal-Regulated Kinase 1/2

Connective tissue growth factor (CTGF) is a potent pro-fibrotic factor, which is implicated in fibrosis through extracellular matrix (ECM) induction in diabetic cardiovascular complications. It is an important downstream mediator in the fibrotic action of transforming growth factor beta (TGFbeta) and is potentially induced by hyperglycemia in human vascular smooth muscle cells (VSMCs). Therefore, the goal of this study is to identify the signaling pathways of CTGF effects on ECM accumulation and cell proliferation in VSMCs under hyperglycemia. We found that high glucose stimulated the levels of CTGF mRNA and protein and followed by VSMC proliferation and ECM components accumulation such as collagen type 1, collagen type 3 and fibronectin. By depleting endogenous CTGF we showed that CTGF is indispensable for the cell proliferation and ECM components accumulation in high glucose-stimulated VSMCs. In addition, pretreatment with the MEK1/2 specific inhibitors, PD98059 or U0126 potently inhibited the CTGF production and ECM components accumulation in high glucose-stimulated VSMCs. Furthermore, knockdown with ERK1/2 MAPK siRNA resulted in significantly down regulated of CTGF production, ECM components accumulation and cell proliferation in high glucose-stimulated VSMCs. Finally, ERK1/2 signaling regulated Egr-1 protein expression and treatment with recombinant CTGF reversed the Egr-1 expression in high glucose-induced VSMCs. It is conceivable that ERK1/2 MAPK signaling pathway plays an important role in regulating CTGF expression and suggests that blockade of CTGF through ERK1/2 MAPK signaling may be beneficial for therapeutic target of diabetic cardiovascular complication such as atherosclerosis.

PDGF-induced Proliferation of Smooth Muscular Cells Is Related to the Regulation of CREB Phosphorylation and Nur77 Expression / 华中科技大学学报（医学）（英德文版）

This study examined the relationship between PDGF-induced proliferation of vascular smooth muscle cells (VSMCs) and Nur77 expression and the effect of atorvastatin on VSMC proliferation and Nur77 in PDGF-treated VSMCs.Rat VSMCs were isolated and cultured.After incubation with atorvastatin or Nur77 siRNA,the cells were stimulated with PDGF and detected for BrdU incorporation to measure the proliferation of the VSMCs.Quantitative PCR and Western blotting were used to determine the Nur77 protein and the CREB phosphorylation level,to observe their relations with PDGF-induced VSMC proliferation.Our results showed that PDGF increased the BrdU incorporation in VSMCs,suggesting that it induced the proliferation of the cells.The VSMC proliferation was associated with increased Nur77 expression and elevated CREB phosphorylation.Atorvastatin inhibited the PDGF-induced VSMC proliferation,suppressed Nur77 expression.After silencing of Nur77 gene,the PDGF-induced VSMC proliferation was decreased.It was concluded that PDGF-induced VSMC proliferation was related to the Nur77 expression and CREB phosphorylation.Atorvastatin reduced the Nur77 expression and,at the same time,inhibited the VSMC proliferation.

A DNA enzyme targeting Egr-1 inhibits rat vascular smooth muscle cell proliferation by down-regulation of cyclin D1 and TGF-â1

We have demonstrated that a synthetic DNA enzyme targeting early growth response factor-1 (Egr-1) can inhibit neointimal hyperplasia following vascular injury. However, the detailed mechanism of this inhibition is not known. Thus, the objective of the present study was to further investigate potential inhibitory mechanisms. Catalytic DNA (ED5) and scrambled control DNA enzyme (ED5SCR) were synthesized and transfected into primary cultures of rat vascular smooth muscle cells (VSMCs). VSMC proliferation and DNA synthesis were analyzed by the MTT method and BrdU staining, respectively. Egr-1, TGF-â1, p53, p21, Bax, and cyclin D1 expression was detected by RT-PCR and Western blot. Apoptosis and cell cycle assays were performed by FACS. Green fluorescence could be seen localized in the cytoplasm of 70.6 ± 1.52 and 72 ± 2.73 percent VSMCs 24 h after transfection of FITC-labeled ED5 and ED5SCR, respectively. We found that transfection with ED5 significantly inhibited cultured VSMC proliferation in vitro after 24, 48, and 72 h of serum stimulation, and also effectively decreased the uptake of BrdU by VSMC. ED5 specifically reduced serum-induced Egr-1 expression in VSMCs, further down-regulated the expression of cyclin D1 and TGF-â1, and arrested the cells at G0/G1, inhibiting entry into the S phase. FACS analysis indicated that there was no significant difference in the rate of apoptosis between ED5- and ED5SCR-transfected cells. Thus, ED5 can specifically inhibit Egr-1 expression, and probably inhibits VSMC proliferation by down-regulating the expressions of cyclin D1 and TGF-â1. However, ED5 has no effect on VSMC apoptosis.

Inhibitory effects and mechanism of ursolic acid on the proliferation of rat aortic smooth muscle cells / 中国药科大学学报

Aim: To observe the effect of ursolic acid(UA)on the proliferation of rat vascular smooth muscle cell(VSMC)induced by high-level glucose and explore its relationship with p38MAPK signal transduction pathway.Methods: The proliferation of VSMC induced by high-level glucose(25 mmol/L glucose)was adopted as model,the inhibition of UA on the proliferation of VSMC was measured by MTT assay,and the expression lev-els of phospho-p38MAPK was detected by cell-based ELISA as well as the expression of c-fos protein was exam-ined by SABC method.Results: UA(20 μmol/L and 40 μmoL/L)inhibited glucose-induced proliferation of VSMC(P <0.05).Compared with the group subjected to glucose induction,UA decreased the expression levels of phosphorylated p38MAPK(P < 0.05),and also inhibited c-fos expression.Conclusion: UA suppressed glucose induced proliferation of VSMC,which might be related to the suppression of the activation of p38MAPK signal transduction pathway,and thereby down-regulated c-fos expression.

Effect of Endothelins on Restenosis after Percutaneous Coronary Intervention (review) / 中国康复理论与实践

@# A general situation on research about the endothelins (ET) such as its synthesis, secretion and the mitogenic activity on vascular smooth muscle cells (VSMC), and its effect on restenosis after percutaneous coronary intervention (PCI) was reviewed by the authors.

The Role of Janus Kinase in Superoxide-mediated Proliferation of Diabetic Vascular Smooth Muscle Cells

To elucidate a potential molecular link between diabetes and atherosclerosis, we investigated the role of Janus tyrosine kinase (JAK) for NAD(P)H oxidase-derived superoxide generation in the enhanced proliferative capacity of vascular smooth muscle cells (VSMC) of Otsuka Long-Evans Tokushima Fatty (OLETF) rat, an animal model of type 2 diabetes. An enhanced proliferative response to 10% fetal bovine serum (FBS) and superoxide generation with an increased NAD(P)H oxidase activity were observed in diabetic (OLETF) VSMC. Both the enhanced proliferation and superoxide generation in diabetic VSMC were significantly attenuated by AG490, JAK2 inhibitor, and PP2, Src kinase inhibitor. Tyrosine phosphorylation of proteins in diabetic VSMC, especially JAK2, was increased compared to control VSMC. Furthermore, the enhanced NAD(P)H oxidase activity in diabetic VSMC was significantly attenuated by AG490 in a dose-dependent manner. Together, these results indicate that the signal pathway which leads to diabetes-associated activation of Src kinase/JAK is critically involved in the diabetic VSMC proliferation through NAD(P)H oxidase activation and superoxide generation.

Effects of PNS on the Apoptosis and Expression of C-myc of Vascular Smooth muscle Cells / 医学研究杂志

Objective To observe the effects of panax notoginseng saponins on the apoptosis and expression of C-myc of vascular VSMC in vitro.Methods VSMC derived from rabbit aorta were cultured in vitro and different concentrations of PNS were added in experimental groups.VSMC apoptosis was evaluated with cell ultrastructure under electron microscopy and flow cytometry.Expression of C-myc was observing by immunocytochemical method.Results The ratio of apoptosis and the expression of C-myc in PNS groups were high than control group.Conclusions PNS can increase the ratio of VSMC apoptosis which may be related the expression promoting of C-myc.

Nitric Oxide Donor, NOR-3, Increased Expression of Cyclooxygenase-2, but not of Cyclooxygenase-1 in Cultured VSMC

NO and cyclooxygenase-2 (COX-2) are contributes to vascular inflammation induced by various stimulation. The mechanism, which explains a linkage between NO and COX-2, could be of importance in promoting pathophysiological conditions of vessel. We investigated the effects of NO donors on the COX-1 and COX-2 mRNA/protein expression, as well as the nitrite production in culture medium of vascular smooth muscle cell (VSMC). VSMC was primarily cultured from thoracic aorta of rat. In this experiments, COX-1 and COX-2 mRNA/protein expressions were analysed and nitrite productions were investigated using Griess reagent. VSMC did not express COX-2 protein in basal condition (Non-lipopolysaccharide (LPS) stimulated). In LPS-stimulated experiments, after 3 hours of NO donor pretreatment, LPS 10 microgram/ml was treated for 24 hours. COX-1 protein expressions were unchanged by SNP and NOR-3. NOR-3 significantly increased COX-2 mRNA/protein expression under LPS stimulation. In contrast, SNP did not increase COX-2 mRNA/protein expression under LPS stimulation. Nitrite production was higher in NOR-3 treatment than SNP treatment under LPS stimulation. These results suggest that the expression of COX-2 in VSMC is regulated by NOR-3, COX-2 expressions were depending on the types of NO donor and LPS stimulation in VSMC.

Androgen Hormone Inhibits Expression of iNOS and COX-2 Protein in Rat Vascular Smooth Muscle Cell

We investigated the effects of testosterone and dihydrotestosterone on inflammatory response of iNOS and COX-2 expression in rat vascular smooth muscle cells. Rat vascular smooth muscle cells (VSMC) stimulated with bacterial lipopolysaccharide (LPS; 10microgram/ml) for 24 hours were incubated with increasing amounts of testosterone and dihydrotestosterone (1 and 100 nM). LPS was found to induce inflammatory response of iNOS and COX-2 mRNA and protein in VSMC. These processes were affected by male sex steroid hormones. For 3 hours, however, pretreatment of the cells with 100 nM each of testosterone and dihydrotestosterone suppressed LPS induced iNOS and COX-2 protein expression. RT-PCR analysis revealed that testosterone and dihydrotestosterone did not inhibit mRNA expression of iNOS and COX-2 stimulated by 24 hours of LPS incubation. Proliferation rate was slower in VSMC treated with testosterone and dihydrotestosterone. Testosterone enhanced androgen receptor expression, and LPS significantly reduced androgen receptor protein expression in VSMC. These results indicate that the expression of both iNOS and COX-2 proteins was suppressed by testosterone and dihydrotestosterone in LPS stimulated VSMC and leading to reduction of vascular inflammation.

Inhibition of Angiotensin II-Induced Vascular Smooth Muscle Cell Hypertrophy by Different Catechins

A cumulative evidence indicates that consumption of tea catechin, flavan-3-ol derived from green tea leaves, lowers the risk of cardiovascular diseases. However, a precise mechanism for this cardiovascular action has not yet been fully understood. In the present study, we investigated the effects of different green tea catechins, such as epigallocatechin-3 gallate (EGCG), epigallocatechin (EGC), epicatechin-3 gallate (ECG), and epicatechin (EC), on angiotensin II (Ang II) -induced hypertrophy in primary cultured rat aortic vascular smooth muscle cell (VSMC). [3H]-leucine incorporation was used to assess VSMC hypertrophy, protein kinase assay, and western blot analysis were used to assess mitogen-activated protein kinase (MAPK) activity, and RT-PCR was used to assess c-jun or c-fos transcription. Ang II increased [3H]-leucine incorporation into VSMC. However, EGCG and ECG, but not EGC or EC, inhibited [3H]-leucine incorporation increased by Ang II. Ang II increased phosphorylation of c-Jun, extracellular-signal regulated kinase (ERK) 1/2 and p38 MAPK in VSMC, however, EGCG and ECG, but not EGC or EC, attenuated c-Jun phosphorylation increased by Ang II. ERK 1/2 and p38 MAPK phosphorylation induced by Ang II were not affected by any catechins. Ang II increased c-jun and c-fos mRNA expression in VSMC, however, EGCG inhibited c-jun but not c-fos mRNA expression induced by Ang II. ECG, EGC and EC did not affect c-jun or c-fos mRNA expression induced by Ang II. Our findings indicate that the galloyl group in the position 3 of the catechin structure of EGCG or ECG is essential for inhibiting VSMC hypertrophy induced by Ang II via the specific inhibition of JNK signaling pathway, which may explain the beneficial effects of green tea catechin on the pathogenesis of cardiovascular diseases observed in several epidemiological studies.

Vascular Collagen Remodeling, Apoptosis and Bcl-2/Bax of Vascular Smooth Muscle Cells in Carotid Artery on SHR / 介入放射学杂志

Objective To observe the vascular collagen remodeling, apoptosis and Bcl-2/Bax of vascular smooth muscle cells in carotid artery on SHR . Methods 12 SHR treated with Irbesartan ,12 SHR without treated Irbesartan ,12 wistar rats were normotensive control group. The vascular volume fraction of Collagen were determined by picrosirius red staining .The expression of the proteins Bcl-2 and Bax were determined by Immunhistochemia,VSMC apoptosis was identified by in situ TDT-mediated dUTP nick end labeling(TUNEL). Results Significant Fibrosis exists in carotid artery of SHR. After 20 week's treating, the vascular volume fraction of Collagen and the ratio of wall/cavity were descended, but weren't parallel. The expression of the protein Bcl-2 and APOI were higher than the subjects of normotensive control, its reduced after treating; The expression of the proteins Bax was similar with control, it increased after treating. Conclusions The results suggest that vascular collagen remodeling exist, its maybe related with apoptosis , the proteins Bcl-2 and Bax of VSMC. The Irbesartan can treat it.

Involvement of NAD (P) H Oxidase in a Potential Link between Diabetes and Vascular Smooth Muscle Cell Proliferation

The cellular mechanisms that contribute to the acceleration of atherosclerosis in diabetes are poorly understood. Therefore, the potential mechanisms involved in the diabetes-dependent increase in vascular smooth muscle cell (VSMC) proliferation was investigated. Using primary culture of VSMC from streptozotocin-induced diabetic rat aorta, cell proliferation assay showed two-fold increase in cell number accompanied with enhanced superoxide generation compared to normal VSMC, 2 days after plating. Both the increased superoxide production and cell proliferation in diabetic VSMC were significantly attenuated by not only tiron (1 mM), a superoxide scavenger, but also by diphenyleneiodonium (DPI; 10micrometer), an NAD (P) H oxidase inhibitor. NAD (P) H oxidase activity in diabetic VSMC was significantly higher than that in control cell, accompanied with increased mRNA expression of p22phox, a membrane subunit of oxidase. Furthermore, inhibition of p22phox expression by transfection of antisense p22phox oligonucleotides into diabetic VSMC resulted in a decrease in superoxide production, which was accompanied by a significant inhibition of cell proliferation. Based on these results, it is suggested that diabetes-associated increase in NAD (P) H oxidase activity via enhanced expression of p22phox contributes to augmented VSMC proliferation in diabetic rats.