Effects of cleavage factor Im25 downregulation in vascular smooth muscle cells on hyperlipidemia in mice / 中华老年医学杂志

Objective:To investigate the impact of cleavage factor Im25(CFIm25)on VSMCs-specific knockdown in the context of hyperlipidemia.Methods:Mice models were constructed with specific knockout of CFIm25 in VSMCs(CFIm25f/+ TaglnCre)and control mice(TaglnCre).The mice were fed a normal diet or high-fat diet(HFD)for 18 weeks and their body weight changes were monitored.ELISA was used to measure serum total cholesterol(TC), triacylglycerol(TG), high-density lipoprotein(HDL-C)and low-density lipoprotein(LDL-C)levels.The extent of aortic lipid deposition in mice was assessed by oil red O staining.Results:During the feeding of a high-fat diet, CFIm25f/+ TaglnCre mice showed a significant increase in body weight compared to the control group[Male(1.01±0.06)g and(0.87±0.31)g, t=7.53, P<0.05; Female: (0.64±0.02)g and(0.35±0.04)g, t=9.68, P<0.05].After 18 weeks of high-fat diet feeding, CFIm25f/+ TaglnCre mice had significantly higher levels of TC[(6.80±0.35)mmol/L and(3.76±0.87)mmol/L, t=5.63, P=0.004], TG[(0.97±0.21)mmol/L and(0.42±0.10)mmol/L, t=4.08, P=0.015], and LDL-C[(5.20±0.30)mmol/L and(2.00±0.98)mmol/L, t=5.40, P=0.006]compared to the TaglnCre group.Specifically, TC levels increased by 80.72%, TG increased by 132.79%, and LDL-C increased by 160.32%.There was a significant increase in aorta lipid deposition and atherosclerotic plaque area in CFIm25f/+ TaglnCre mice( P<0.05). Conclusions:The research indicated that VSMCs-specific CFIm25 knockdown in mice further worsened hyperlipidemia and atherosclerotic lesions.

Efecto del Camphenol Plus sobre el músculo liso vascular de vena porta en ratas Wistar / Effect of Camphenol Plus on portal vein vascular smooth muscle in Wistar rats

RESUMEN Introducción: uno de los antisépticos comúnmente empleado en Estomatología desde el pasado siglo y que mantiene su uso hasta la actualidad, lo constituye el Camphenol Plus. Son escasos los reportes científicos de su efecto sobre el endotelio y la dinámica contráctil del músculo liso vascular, en especial de tejidos venosos como la vena porta hepática. Objetivo: determinar el efecto del Camphenol Plus sobre el músculo liso vascular de la vena porta. Métodos: se realizó una investigación experimental preclínica, con la utilización de 21 venas porta obtenidas de ratas Wistar. Las preparaciones realizadas se colocaron en baño de órganos, se registró la tensión desarrollada por el músculo liso vascular tras la adición de diez microlitros de Camphenol Plus, en diferentes concentraciones y durante diferentes intervalos de tiempo. Resultados: el Camphenol Plus, tras la preactivación del musculo liso vascular de la vena porta, indujo vasorelajación, la que se incrementó durante todo el tiempo de estudio y según el incremento de las concentraciones del medicamento. Existieron diferencias significativas entre los valores de tensión promedios registrados en los diferentes intervalos de tiempo con los de la tensión espontánea basal y la tensión base inicial. Conclusiones: el Camphenol Plus, indujo "in vitro", relajación de la musculatura lisa de la vena porta a través de un acoplamiento excitación-contracción de tipo farmacomecánico.

ABSTRACT Introduction: Camphenol Plus is one of the antiseptics commonly used in Dentistry since the last century and still in use today. There are few scientific reports of its effect on the endothelium and contractile dynamics of vascular smooth muscle, especially in venous tissues such as the hepatic portal vein. Objective: to determine the effect of Camphenol Plus on the vascular smooth muscle of the portal vein. Methods: a preclinical experimental investigation was carried out using 21 portal veins obtained from Wistar rats. The preparations were placed in an organ bath and the tension developed by the vascular smooth muscle was recorded after the addition of ten microliter of Camphenol Plus, at different concentrations and during different time intervals. Results: Camphenol Plus, after the preactivation of the vascular smooth muscle of the portal vein, induced relaxation, which increased throughout the study time and according to the increase in drug concentrations. There were significant differences between the average tension values recorded in the different time intervals with those of the basal spontaneous tension and the initial baseline tension. Conclusions: Camphenol Plus induced "in vitro" relaxation of portal venous smooth muscles through a pharmacomechanical excitation-contraction coupling.

Mechanisms for Nogo-B mediating mitochondrial reactive oxygen species generation during vascular remodeling in mice / 中华老年医学杂志

Objective:To investigate the role of Nogo-B in mitochondrial reactive oxygen species(m-ROS)production and vascular remodeling in vascular smooth muscle cells(VSMCs), and to further clarify the molecular mechanism for Nogo-B in m-ROS production via regulating ATP synthase expression.Methods:A mouse model of vascular remodeling was established.The expression of Nogo-B in mouse smooth muscle cells was detected.Forty mice were divided into the AAV-NC+ control, AAV-NC+ angiotensin Ⅱ(AngⅡ), AAV-Nogo-B+ control and AAV-Nogo-B+ AngⅡ groups(n=10 for each group). VSMCs cultured in vitro were divided into the control group and the Nogo-B overexpression group(Ad-Nogo-B). The expression of Nogo-B in VSMCs in vitro stimulated with AngⅡ was detected.Through experiments conducted in vivo, Nogo-B was overexpressed in VSMCs, then VSMCs were stimulated with AngⅡ, and m-ROS production, tissue fibrosis and mitochondrial function were examined.The regulatory effects of Nogo-B on m-ROS production were explored.Molecular mechanisms for NoGO-B in vascular remodeling via regulating ATP synthase/m-ROS production were examined. Results:Compared with the control group, the expression of Nogo-B was decreased in VSMCs treated with AngⅡ(0.36±0.13 vs.1.00±0.13, t=8.44, P<0.05). The production of m-ROS, fibrosis and mitochondrial dysfunction were increased in VSMCs during vascular remodeling( P<0.05), while overexpression of Nogo-B significantly reduced m-ROS production, fibrosis and mitochondrial dysfunction( P<0.05). ATP synthase expression in VSMCs was positively regulated by Nogo-B.ATP synthase expression was higher in the AAV-Nogo-B+ AngⅡ group than in the AAV-NC+ AngⅡ group(0.86±0.14 vs.0.49±0.17, t=-3.97, P<0.05). The production of m-ROS was reduced by Nogo-B and was lower in the AAV-Nogo-B+ AngⅡ group than in the AAV-NC+ AngⅡ group(1.28±0.34 vs.3.26±0.57, t=7.18, P<0.05). Meanwhile, the ability of Nogo-B to mitigate the deleterious effects of oxidative stress in VSMCs could be offset by oligomycin. Conclusions:Nogo-B participates in vascular remodeling by regulating ATP synthase-mediated m-ROS production.

Effects of ezetimibe and rosuvastatin on the expression of Caveolin-1 mRNA in smooth muscle derived foam cells / 中国医师杂志

Objective To investigate the influence of ezetimibe combined with rosuvastatin on expression of Caveolin-1 in smooth muscle derived foam cells induced by oxidized low density lipoprotein (oxLDL).Methods The rat thoracic aortic smooth muscle cells (VSMCs) were selected from generations 3-5 in logarithmic growth cycle.The rat vascular smooth cells were induced using oxidized low density lipoprotein(ox-LDL 50 μg/ml for 48 h) to establish foam cell model.The normal cultured rat thoracic aortic smooth muscle cells were used as blank control group.Foam cells were divided into foam cell group,different concentrations of ezetimibe group,different concentrations of rosuvastatin group,combination group.The foam cells were incubated with different doses of ezetimibe (3.0,10.0,30.0 μmol/L) or rosuvastatin (0.1,1.0,5.0 μmol/L) for 24 h,or cultured with rosuvastatin 5.0 μmol/L + ezetimibe 30.0 μmol/L in combination groups.Oil red O staining was used to identify foam cell models.The expression of Caveolin-1 mRNA was detected by real-time fluorescent quantitative polymerase chain reaction (qRT-PCR).Results Compared with blank control group,the mRNA expression of Caveolin-1 in foam cell group were decreased significantly [(0.248 7 ± 0.042 0) vs (1.004 1 ± 0.017 1),P ＜ 0.05].Compared with foam cell group,the mRNA expression of Caveolin-1 was increased in a dose-dependent manner in ezetimibe group and rosuvastatin group [(0.371 3 ±0.025 2),(0.489 8 ±0.027 9),(0.726 1 ±0.029 1) vs (0.248 7 ±0.042 0);(0.460 2±0.022 8),(0.623 7 ±0.028 8),(0.751 8 ±0.043 1) vs (0.248 7 ±0.042 0),P ＜0.05].Compared with the ezetimibe (30.0 μmol/L) and the rosuvastatin (5.0 μmol/L),the mRNA expression of Caveolin-1 in combined group were increased,the difference was statistically significant [(0.726 1 ±0.029 1),(0.751 8 ± 0.043 1) vs (0.937 6 ± 0.029 7),P ＜ 0.05].Conclusions Ezetimibe and rosuvastatin can promote the reverse transport of cholesterol (RCT) in smooth muscle derived foam cells by upregulating expression of Caveolin-1 mRNA.And the combination of ezetimibe (30.0 μmol/L) and rosuvastatin (5.0 μmol/L) has more significant effect.

Inhibitory effects of solid lipid nanoparticles of rhynchophylline on proliferation of rat vasculars mooth muscle cells induced by TGF-β1 / 国际中医中药杂志

Objective To observe the effect of Rhy-SLN on the proliferation of rat vascular smooth muscle cells (VSMC) induced by TGF-β1, and explore the mechanism. Methods The primary culture of rat thoracic aortic vascular smooth muscle cells was studied by tissue block culture method. The cells were divided into the control group, TGF-β1 group, TGF-β1+ the high, medium and low dosage groups of Rhy-SLN. In addition to the control group, the cells of the other groups were involved in the intervention of TGF-β1 of 20 g/L, and the high, medium and low dosage groups of Rhy-SLN cells were involved in the intervention of 25, 50, 100 mg/L of the hook teng solid lipid nanoparticles. After 24 hours of culture, MTT assay was used to detect cell proliferation inhibition rate in each group, and the cell cycle was detected by flow cytometry. The expression of c-myc and c-Fos protein in each group was detected by Western blot method. Results Compared with the TGF-β1 group, the absorbance value (0.457 ± 0.046 vs. 0.975 ± 0.049) of TGF-β1+ rhy-sln high dose group significantly decreased (P<0.01); the number of S phase cells (15.87% ± 2.47%, 15.23% ± 1.69%, 17.02% ± 2.87% vs.38.58% ± 2.68%)of TGF-β1+rhy-sln in each dose group significantly decreased(P<0.01);The c-myc(48.65 ±3.65,50.69 ± 4.16,55.29 ± 3.67 vs.68.21 ± 3.25)and c-Fos(38.78 ± 4.25,43.56 ± 3.69,46.58 ± 3.57 vs.66.54 ± 4.09) of the TGF-β1+ rhy-sln each dose group significantly decreased (P<0.01). Conclusions The Rhy-SLN can inhibit the proliferation of VSMC in rats induced by TGF-β1.Its mechanism is related to the conversion of G0/G1 phase to the S phase and the expression of the reduction of c-myc and c-fos protein.

Research advances in signal pathway and molecular mechanism of vascular calcification / 中华老年医学杂志

Vascular disease,such as atherosclerosis and diabetic vasculopathy,is frequently complicated by vascular calcification.Previously believed to be an end-stage process of unregulated mineral precipitation,it is now well established to be a multi-faceted disease.The numerous regulatory signaling pathways that influence vascular calcification,and these pathways are directly or indirectly related to bone remodeling.This review provides a brief overview of the research progresses of vascular calcification-related molecular signaling pathways from the perspective of osteoblastic differentiation.

The protective mechanism of D-pinitol on advanced glycation end products-induced proliferation and migration in vascular smooth muscle cells / 中华老年医学杂志

Objective To investigate the effect and its mechanism of D-pinitol on advanced glycation end products(AGEs)-induced proliferation and migration in mouse aortic vascular smooth muscle cells (VSMC).Methods VSMCs were isolated from mouse aorta and cultured in vitro.Effects of different concentrations of D-pinitol on proliferation and migration of VSMCs were observed by using the AGEs-induced glycosylation injury model of VSMCs.Cell proliferation and migration were detected by CCK-8 assay and cell scratch,respectively.The protein expression levels of transforming growth factor-β1(TGF-β1),p-smad2,p-smad3 and asporin were determined by Western blot.Results Compared with control group,AGEs group showed the increased protein expression levels of asporin,TGF-β1,p-smad2 and p-smad3 (40.06 ± 4.50 vs.17.47 ± 0.57),(55.25 ± 2.07 vs.14.42± 2.07),(0.97 ± 0.02 vs.0.47 ± 0.02),(0.45±0.01 vs.0.26 ± 0.02),all P＜ 0.01.Compared to AGEs group,D-pinitol group could inhibit the cell proliferation and migration and cause dose-dependent decreases of protein expressions of TGF-β1,p-smad2,p-smad3 and asporin(P ＜ 0.05 or P＜0.01).Conclusions D-pinitol can inhibit AGEs-induced cell proliferation and migration in mouse aortic VSMCs.Asporin may participate in the VSMCs extracellular matrix remodeling via TGF-β/smad pathway.

Effects of a Single Bout of Resistance Exercise in Different Volumes on Endothelium Adaptations in Healthy Animals / Efeitos de uma Sessão de Exercício Resistido em Diferentes Volumes sobre Adaptações Endoteliais em Animais Saudáveis

Abstract Background: Resistance exercise (RE) has been recommended for patients with cardiovascular diseases. Recently, a few studies have demonstrated that the intensity of a single bout of RE has an effect on endothelial adaptations to exercise. However, there is no data about the effects of different volumes of RE on endothelium function. Objective: The aim of the study was to evaluate the effects of different volumes of RE in a single bout on endothelium-dependent vasodilatation and nitric oxide (NO) synthesis in the mesenteric artery of healthy animals. Methods: Male Wistar rats were divided into three groups: Control (Ct); low-volume RE (LV, 5 sets x 10 repetitions) and high-volume RE (HV, 15 sets x 10 repetitions). The established intensity was 70% of the maximal repetition test. After the exercise protocol, rings of mesenteric artery were used for assessment of vascular reactivity, and other mesenteric arteries were prepared for detection of measure NO production by DAF-FM fluorescence. Insulin responsiveness on NO synthesis was evaluated by stimulating the vascular rings with insulin (10 nM). Results: The maximal relaxation response to insulin increased in the HV group only as compared with the Ct group. Moreover, the inhibition of nitric oxide synthesis (L-NAME) completely abolished the insulin-induced vasorelaxation in exercised rats. NO production showed a volume-dependent increase in the endothelial and smooth muscle layer. In endothelial layer, only Ct and LV groups showed a significant increase in NO synthesis when compared to their respective group under basal condition. On the other hand, in smooth muscle layer, NO fluorescence increased in all groups when compared to their respective group under basal condition. Conclusions: Our results suggest that a single bout of RE promotes vascular endothelium changes in a volume-dependent manner. The 15 sets x 10 repetitions exercise plan induced the greatest levels of NO synthesis.

Resumo Fundamentos: O exercício resistido (ER) tem sido recomendado para pacientes com doenças cardiovasculares. Recentemente, alguns estudos demonstraram que a intensidade de uma sessão de ER exerce um efeito sobre a disfunção endotelial. No entanto, não há dados sobre os efeitos de diferentes volumes de ER sobre a função endotelial. Objetivo: O objetivo deste estudo foi avaliar os efeitos de diferentes volumes de ER, realizados em uma única sessão, sobre a vasodilatação dependente do endotélio e síntese de óxido nítrico (NO) em artéria mesentérica de animais saudáveis. Métodos: Ratos Wistar machos foram divididos em três grupos: Controle (Ct); baixo volume (BV, 5 séries x 10 repetições) e alto volume de ER (AV, 15 séries x 10 repetições). Foi estabelecida a intensidade de 70% do teste de repetição máxima. Após o protocolo de exercício, anéis de artéria mesentérica foram utilizados na avaliação da reatividade vascular, e outras artérias mesentéricas foram preparadas para a detecção da produção de NO por fluorescência com para do DAF-FM. A resposta à insulina pela síntese de NO foi avaliada estimulando-se os anéis vasculares com insulina (10nM). Resultados: A resposta máxima do relaxamento induzido por insulina foi aumentada somente no grupo AV em comparação ao grupo Ct. Além disso, a inibição da síntese do NO (L-NAME), aboliu completamente o relaxamento vascular induzido por insulina em ratos exercitados. A produção de NO mostrou um aumento dependente do volume no endotélio e no músculo liso. No endotélio, apenas os grupos Ct e BV mostraram aumento significativo na síntese de NO quando comparado aos seus respectivos grupos sob condição basal. No entanto, no músculo liso, a fluorescência foi aumentada em todos os grupos quando comparados aos seus respectivos grupos sob a condição basal. Conclusões: Nossos resultados sugerem que uma única sessão de ER foi capaz de promover adaptações no endotélio vascular. Além disso, nós observamos que este efeito é volume-dependente e o volume de 15 séries x10 repetições induziu o maior aumento na síntese de NO.

Expression of TRPC1-BK Signal Complex in Aortic Smooth Muscle Tissue in Experimental Mice of Atherosclerosis / 中国循环杂志

Objective: To observe the expression of transient receptor potential channel-1—large conductance Ca2+-activated K+channel (TRPC1-BK) signal complex in aortic smooth muscle tissue in experimental mice of atherosclerosis (AS). Methods: Our research included in 2 groups: Control group, wild C57BL/6J mice were fed by normal diet and AS group, ApoE-/- mice were fed by high fat diet to establish AS model. All animals were treated for 10 weeks, n=10 in each group. The total RNA and protein were extracted from aortic smooth muscle tissue in sacrificed mice. The mRNA and protein expressions of TRPC1, BKα and BKβ1 subunit were measured by RT-PCR, Western blot analysis and immunohistochemistry staining. Results: By RT-PCR examination, compared with Control group, AS group showed increased mRNA expression of TRPC1, P<0.05 and decreased mRNA expressions of BKα and BKβ1 subunit, both P<0.01. By Western blot analysis, compared with Control group, AS group had elevated protein expression of TRPC1, P<0.05 and reduced protein expressions of BKα and BKβ1 subunit, both P<0.01; by immunohistochemistry staining, AS group had the higher protein expression of TRPC1, P<0.01 and the lower protein expressions of BKα and BKβ1 subunit, both P<0.05. Conclusion: The mRNA and protein expressions of TRPC1-BK signal complex were affected in aortic smooth muscle tissue in AS mice, which speculated that TRPC1-BK signal complex might be become a new target for treating the relevant vascular disease.

Bier's spots with onset in childhood

Abstract Bier spots are small, irregular, hypopigmented macules that are usually found on the arms and legs. The macules disappear when the limb is raised. Bier spots have been reported in association with a number of conditions but there is no consistent association to specific desease. Although they usually affect young adults, we report a case of Bier spots that began in childhood. As an asymptomatic and possibly transitional condition, the disease does not require treatment.

Jabuticaba-Induced Endothelium-Independent Vasodilating Effect on Isolated Arteries / Efeito Vasodilatador Independente do Endotélio Induzido pela Jabuticaba (M. cauliflora) em Artérias Isoladas

Abstract Background: Despite the important biological effects of jabuticaba, its actions on the cardiovascular system have not been clarified. Objectives: To determine the effects of jabuticaba hydroalcoholic extract (JHE) on vascular smooth muscle (VSM) of isolated arteries. Methods: Endothelium-denuded aortic rings of rats were mounted in isolated organ bath to record isometric tension. The relaxant effect of JHE and the influence of K+ channels and Ca2+ intra- and extracellular sources on JHE-stimulated response were assessed. Results: Arteries pre-contracted with phenylephrine showed concentration-dependent relaxation (0.380 to 1.92 mg/mL). Treatment with K+ channel blockers (tetraethyl-ammonium, glibenclamide, 4-aminopyridine) hindered relaxation due to JHE. In addition, phenylephrine-stimulated contraction was hindered by previous treatment with JHE. Inhibition of sarcoplasmic reticulum Ca2+ ATPase did not change relaxation due to JHE. In addition, JHE inhibited the contraction caused by Ca2+ influx stimulated by phenylephrine and KCl (75 mM). Conclusion: JHE induces endothelium-independent vasodilation. Activation of K+ channels and inhibition of Ca2+ influx through the membrane are involved in the JHE relaxant effect.

Resumo Fundamentos: Embora a jabuticaba apresente importantes efeitos biológicos, suas ações sobre o sistema cardiovascular ainda não foram esclarecidas. Objetivos: Determinar os efeitos do extrato de jabuticaba (EHJ) sobre o músculo liso vascular (MLV) em artérias isoladas. Métodos: Aortas (sem endotélio) de ratos foram montadas em banho de órgãos isolados para registro de tensão isométrica. Foram verificados o efeito relaxante, a influência dos canais de K+ e das fontes de Ca2+ intra- e extracelular sob a resposta estimulada pelo EHJ. Resultados: Artérias pré-contraídas com fenilefrina apresentaram relaxamento concentração-dependente (0,380 a 1,92 mg/mL). O tratamento com bloqueadores de canais de K+ (tetraetilamônio, glibenclamida, 4-aminopiridina) prejudicaram o relaxamento pelo EHJ. A contração estimulada com fenilefrina também foi prejudicada pelo tratamento prévio com EHJ. A inibição da Ca2+ATPase do reticulo sarcoplasmático não alterou o relaxamento pelo EHJ. Além disso, o EHJ inibiu a contração causada pelo influxo de Ca2+ estimulado por fenilefrina e KCl (75 mM). Conclusão: O EHJ induz vasodilatação independente do endotélio. Ativação dos canais de K+ e inibição do influxo de Ca2+ através da membrana estão envolvidas no efeito relaxante do EHJ.

Dynamic alteration of microRNA in high phosphorus induced calcification of vascular smooth muscle cell / 北京大学学报(医学版)

Objective:To study the change of microRNA during the early stage of high phosphorus in-duced vascular smooth muscle cell (VSMC)calcification and its related mechanism.Methods:The in vitro calcification model was created through stimulating VSMC cell line A7r5 with high Pi (2.6 mmol /L)for 7 d.The calcification was validated through ocresolphthalein complexone colorimetry to detect the cellular calcium content,real-time PCR to measure the calcification-related gene expression and alizarin red staining to observe the formation of calcium nodules.Based on the cell calcification model,micro-RNA microarray array was applied to screen the profiles of microRNA expression in VSMC following high Pi stimulation for different periods (0,3 and 12 h).The array data were analyzed by TAMtool to explore the activated signaling pathway.Results:The calcium content of A7r5 cells induced by high Pi was in-creased 9.6 times high as cells without Pi treatment (P <0.05 ).VSMC contractile phenotype genes (SM-αactin,SM22)were down-regulated (P <0.05 ),while calcification-related genes (BMP2, MSX2,Runx2)were up-regulated (P <0.05)in VSMC stimulated by high Pi.The calcium nodules were obviously formed in cells after 7 d high Pi treatment.In microarray experiment,680 individual mi-croRNAs were detected in high Pi-treated VSMCs at different time points (0,3 and 12 h).Among these genes,miR-183,miR-664 and miR-9 * were increased whereas miR-542-5P,let-7f and miR-29a were decreased in time-dependent manners.Twenty-six kinds of signaling pathways,including cell apoptosis, differentiation and proliferation,were significantly activated.All these activated pathways were associated with calcification.Conclusion:This study implies that microRNA changed in high Pi-induced VSMCs may involve in the process of calcification.

Effect of large conductance Ca2+-activated K+ channel current and cytosolic calcium concentrations in retinal artery smooth muscle cells on diabetic retinal artery tension / 中华实验眼科杂志

Background Diabetic retinopathy (DR) is a common microvascular complications of the retina,retinal vascular smooth muscle cells of large conductance calcium-activated potassium channels (BK) is a major factor in regulating vasomotor and hemodynamic.Currently,functional changes of BK channel in retinal artery smooth muscle cells (RASMCs) and its role in DR were rarely reported.Objective This study was to investigate the early vascular damage mechanisms in DR by detecting the changes of BK channels current,calcium concentration and open probability (NP0) of BK channel with different calcium concentration in RASMCs of normal and diabetic rats.Method Fifty SPF SD 8-12 weeks old rats were randomly divided into normal control group and diabetic model group.Forty diabetic rats was intraperitoneally injected with 60 mg/kg streptozotocin to form type 1 diabetic model,10 rats (the normal control group) were injected sodium citrate solution with the same manner.Fluorescent probe was applied to detect calcium concentration in rat RASMCs;RASMCs were isolated by using enzyme digestion,and BK-channel electric currents and calcium concentrations in the RASMCs were measured by whole-cell patch clamp technique and fluorescence assay,respectively.The NP0 of BK channel was measured by single patch clamp technique.Results Diabetic models were successfully established in 36 rats with the success rate 90％.When stimulation voltage is greater than 60 mV,the current density of BK channel in RASMCs of diabetic model group decreased;when stimulating voltage was 100 mV,the BK channel currents of RASMCs in the normal control group and diabetic model group were (100±23) PA/PF and (50 ± 7) PA/PF,the difference was statistically significant (t =19.80,P ＜ 0.05).After adding specific BK channel blocker African scorpion toxin 100 nmol,the BK channel current in the normal control group significantly reduced,and that in the diabetes model group was not significantly changed;the calcium ion concentrations in RASMCs were (123±11)nmol/L and (255± 10)nmol/L in the normal control group and diabetic model group,the difference was statistically significant (t =32.50,P＜0.05).When stimulation voltage was 60 mV,with increasing calcium ion concentration,the NP0 of BK channel increased (F =15.28,P＜0.05).Conclusions The electric current and NP0 of BK-channel are obviously reduced and the calcium concentration is evidently elevated in RASMCs of diabetic rats,suggesting that the abnormal of BK-channel is probably one of the important causes of retinal artery abnormal contraction in diabetic rats.

Study on the action mechanism of basic fibroblast growth factor on vascular smooth muscle cells in spontaneously hypertensive rats / 中华老年医学杂志

Objective To explore the action mechanism of basic fibroblast growth factor (bFGF) on vascular smooth muscle cells (VSMCs) in spontaneously hypertensive rats (SHR).Methods Ts were obtained from SHR and SD rats.The aortic VSMCs were cultured in vitro by tissue explant method.VSMCs were treated with different concentration of exogenous bFGF (0 ng/ml,20 ng/ml,40 ng/ml,60 ng/ml,80 ng/ml,100 ng/ml) for 48 h,then cell proliferation was detected by 3 (4,5 dimethylthiazol)2,5 diphenyltetrazolium bromide (MTT) colorimetric assay.VSMCs from SHR in control group were treated with bFGF (100 ng/ml) for 48h.VSMCs from SHR in treatment group were treated with bFGF (100 ng/ml) plus Proteinkinase C(PKC) inhibitor (staurosporine) for 48 h.Results After treatment with different concentration (0 ng/ml,20 ng/ml,40 ng/ml,60 ng/ml,80 ng/ml,100 ng/ml) of bFGF for 48 h,the values measured by MTT colorimetric method were 0.402 ± 0.103,0.605 ±0.090,0.696 ± 0.131,0.812 ± 0.080,0.901 ± 0.065,1.056±0.078 respectively in aortic VSMCs from SD rats,and 0.404±0.065,0.507±0.078,0.608±0.057,0.704 ± 0.107,0.812 ± 0.097,0.908 ± 0.032 respectively in aortic VSMCs from SHR.Compared with control group,the values measured by MTT colorimetric method were decreased in treatment group (P＜0.05).The proliferative effect of bFGF in aortic VSMCs from SHR was attenuated after administration of PKC inhibitor staurosporine.Conclusions Exogenous bFGF administration promotes VSMCs proliferation in SHR and SD rats in a concentration-dependent manner.PKC plays an important role in the signal transduction mechanism in VSMCs proliferation by exogenous bFGF.

Effect of aging on transcription and protein expressions of procollagen α polypeptide gene of vascular smooth muscle cells in rat / 中华老年医学杂志

Objective To investigate the effects of aging on procollagen α polypeptide gene transcription and protein expression in rat vascular smooth muscle cells.Methods Vascular smooth muscle cells from thoracoabdominal aorta in neonate and 9 months old healthy Wistar rats were cultured in vitro.Results Transcription polymerase chain reaction(RT PCR) and Western blotting were used to detect type Ⅰ and Ⅲ pro-collagen α polypeptide mRNA and protein.The RT-PCR displayed that type Ⅰ procollagen α polypeptide mRNA expression had no significant difference between young group and adult group [(76.62±1.05) vs.(78.37±2.42),P＞0.05].Type Ⅲ procollagen α polypeptide mRNA expression was (105.40 ± 2.66) in young group and (123.10 ± 3.81) in adult group(P＞0.05).Type Ⅰ procollagen α polypeptide mRNA expression was (3.13 ±0.54) in young group and (4.63 ± 1.03) in adult group (P=0.05).Type Ⅲ procollagen α polypeptide mRNA expression had no significant difference between the adult and young groups[(6.86 ±0.41) vs.(7.68±0.63),P＞0.05].Type Ⅰ and type Ⅲ procollagen α polypeptide protein expressions were increased significantly in adult group as compared with the young group [(0.10 ± 0.03) vs.(0.06±0.03),(0.58±0.06) vs.(0.40±0.02),both P＜0.05].Conclusions Aging increases the procollagen α polypeptide level in vascular smooth muscle cell,which may involve in the development of vascular remodeling and atherosclerosis.

The effects of Slit2 protein on proliferation and migration of rats vascular smooth muscle cells stimulated by TNF-α / 重庆医学

Objective To observe the effects of Slit2 protein on the proliferation and migration of VSMCs .Methods The VSMCs was cultured in our laboratory .The experiment was divided into two parts ,part one:VSMCs were divided into normal con‐trol group and experimental groups(culture with 50 ,75 ,100 ,125 and 150 ng/mL Slit2 respectively);part two :VSMCs were divided into normal control group ,positive control group(culture with TNF‐α10 ng/mL) and experimental groups(culture with TNF‐α10 ng/mL+Slit2 50 ng/mL ,TNF‐α10 ng/mL+Slit2 75ng/mL ,TNF‐α10 ng/mL+ Slit2 100 ng/mL ,TNF‐α10 ng/mL+ Slit2 125 ng/mL and TNF‐α10 ng/mL+Slit2 150 ng/mL respectively) .To detect proliferation and migration of VSMCs by CCK‐8 and tran‐swell experiment .Results The difference of OD value and numbers of VSMCs has no statistical significance in the presence of Slit 2 (P=0 .516 ,P=0 .52) .The numbers of VSMCs has statistical significance between control and positive control groups (P=0 .00) . The numbers of VSMCs in experimental groups were fewer than positive control group (P<0 .05) ,whereas the difference of OD value still has no statistical significance between experimental and positive groups (P= 0 .173) .Conclusion Recombinant Slit2 could inhibits migration in VSMCs induced by TNF‐α,whereas it has no effect on proliferation of VSMCs .

The different suppression on voltage-dependent potassium channels currents of smooth muscle cells from cerebral pial arteries and penetrating arteries by subarachnoid hemorrhage / 中华神经科杂志

Objective To study the effect of subarachnoid hemorrhage (SAH) on voltagedependent potassium channels (Kv) currents of smooth muscle cells,which is hypothesized to be different between cerebral pial arteries and penetrating arteries.Methods Smooth muscle cells from cerebral pial arteries and penetrating arteries in rats were enzymatically isolated 72 h after SAH,and patch clamp was used to test the relative cell size,resting potential and Kv currents.Results Resting potential of either pial ((45.63 ±1.18) mV) or penetrating artery ((41.55-± 1.19) mV) was shifted positively by SAH,even more significantly in latter (F =8.24,P ＜ 0.05 ; F =9.36,P ＜ 0.01) ; Resting potential of pial artery of control ((38.76 ± 1.03) mV),penetrating artery of control ((38.53 ± 0.67) mV),pial artery of SAH ((36.87 ± 1.49) mV) and penetrating artery of SAH((37.89 ± 1.24) mV) were shifted positively to the same level by 1 μmol/L 4-aminopyridine (4AP; F =3.08,P ＞0.05).Maximum Current Density (Imax) of either pial ((20.82 ±0.59) pA/pF) or penetrating artery ((15.15 ±0.37) pA/pF) was compromised by SAH,also more significantly in latter (F =6.22,P ＜ 0.05) ; Imax of pial artery of control (9.15 ± 0.16),penetrating artery of control (9.04 ± 0.36),pial artery of SAH (8.77 ± 0.26) and penetrating artery of SAH (9.12 ± 0.17) were decreased to the same level by 1 μmol/L 4AP (F =2.96,P ＞ 0.05).Conclusions SAH probably shares the similar pathway with Kv blocker (4AP) in Kv currents inhibition.Further,SAH differently inhibits smooth muscle cells Kv currents and resting potential of cerebral pial arteries and penetrating arteries,which may be related with their different sensitivity towards cerebral vasospasm following SAH.

Effect of transplantation of mesenchymal stem cells transfected with the human receptor activity modifying protein 1 gene on post-angioplasty proliferation and apoptosis of vascular smooth muscle cells in rabbits / 中华老年医学杂志

Objective To explore the effect of transplantation of mesenchymal stem cells (MSCs) transfected with the human receptor activity modifying protein 1 (hRAMP1) gene on proliferation and apoptosis of vascular smooth muscle cells (VSMCs) after carotid balloon angioplasty was performed in rabbits with carotid atherosclerosis.Methods Density gradient centrifugation and adherent culture were carried out to obtain MSCs,which were then transinfected with an adenovirus vector carrying the hRAMP1 gene or an empty adenovirus vector.A rabbit model of atherosclerotic stenosis and balloon angioplasty was successfully established.Results were randomly divided into three groups:the hRAMP1-MSCs group,theadipose-derived MSCs (Ad-MSCs) group and the control group.MSCs were transinfected with Ad-EGFP-hRAMP1,Ad-EGFP or PBS by transplantation into the injured carotid arteries.Homing and differentiation were assessed with MSCs harvested at 7 d.With MSCs collected at 28 d,Western blotting was used to measure the expression of the hRAMP1 target gene in the carotid artery; the neointima and media area in the injured carotid arteries were estimated; carotid artery morphology was examined with H&E staining; and the proliferation and apoptosis of VSMCs were determined by immunohistochemistry and TUNEL.Results The expression of CD31 and EGFP was found in proliferating neointima lesions at 7d in the hRAMP1-MSCs group and the Ad-MSCs group.At 28d of MSC transplantation,the level of RAMP1 significantly increased in the hRAMP1-MSCs group,compared with the Ad-MSCs and control groups [(63.0±4.9) vs.(28.3±2.5) and (27.2±7.2),all P＜0.05],but there was no differencein the RAMP1 level between the Ad MSCs group and the control group (P＞0.05).Positive expression of the α-smooth muscle antibody (α-SMA) was found in all three groups at 28 d of MSC transplantation.The thickness of the hyperplastic neointima significantly decreased in the hRAMP1-MSCs group,compared with the other two groups (P＜0.05),and was lower in the Ad-MSCs group than in the control group (P＜0.05).The expression of proliferating cell nuclear antigen (PCNA) was lower in the hRAMP1-MSCs group than in the Ad-MSCs and control groups at 28d of MSC transplantation (P ＜0.05),while the PCNA level was lower in the Ad-MSCs group than in the control group (P＜ 0.05).The VSMC apoptosis rate significantly increased in the hRAMP1-MSCs group,compared with the Ad MSCs and control groups (P＜0.05),and was the lowest in the control group (P＜0.05).Conclusions Gene-modified stem cell therapy can effectively inhibit vascular intimal hyperplasia,thereby reducing restenosis after angioplasty.

The pathologic mechanism underlying hypertension-induced decline in arterial elasticity / 中华老年医学杂志

Objective To investigate the effect of hypertension on the large artery elasticity index (C1),the small artery elasticity index (C2) and the medial structure of the ascending aorta as well as the relationship between artery elasticity and the medial structure of the ascending aorta.Methods Sixty patients with CHD receiving coronary artery bypass graft surgery at our hospital were divided into two groups:30 patients in the hypertension group and 30 patients in the non-hypertension group.C1 and C2 were measured using the CVProfilor DO-2020 system.Sections of tissues taken from the anterior wall of the ascending aorta during the surgery were subjected to Masson's trichrome staining for the detection of vascular smooth muscle and collagen fibers and Weigert's resorcin-fuchsin staining for the detection of elastic fibers.The relative areas of vascular smooth muscle fibers,collagen fibers and elastic fibers of the ascending aorta were measured by a computer image analysis system under the light microscope.The linear correlations of C1 and C2 with the medial structure of the ascending aorta were analyzed.Results C1 in the non hypertension group was higher than that in thehypertensiongroup[11.9±1.8 (ml/mmHg×10) w 13.1±2.5 (ml/mmHg×10),t 2.22,P ＜0.05].In the media of the ascending aorta,the relative content of collagen fibers was higher,while the relative content of elastic fibers was lower in the hypertension group than in the non-hypertension group [(46.0±3.8)％ w (42.2±3.0)％,(17.5±3.5)％ vs.(19.3 2.7)％,respectively,t=4.24 and 2.20,P＜0.01 or 0.05].C1 was positively correlated with the relative content of elastic fibers but negatively correlated with the relative content of collagen fibers in both groups (r=0.52 and 0.39,respectively,P＜0.05 or 0.01).Conclusions The main pathogenic basis of hypertension-induced decline in arterial elasticity in CHD patients is increased collagen fibers and reduced elastic fibers with disorganization of the two types of components.C1 may accurately reflect the effect of hypertension on medial collagen fibers and elastic fibers in the ascending aorta.