Proliferation Of Pulmonary Artery Smooth Cells Research Articles

Parthenolide attenuates hypoxia-induced pulmonary hypertension through inhibiting STAT3 signaling

BackgroundPulmonary hypertension (PH) is a chronic lung disease characterized by the progressive pulmonary vascular remodeling with increased pulmonary arterial pressure and right ventricular failure. Pulmonary vascular remodeling involves the proliferation, migration, and resistance to apoptosis of pulmonary artery smooth cells (PASMCs). Parthenolide (PTN) is a bioactive compound derived from a traditional medical plant feverfew (Tanacetum parthenium), and it has been studied for treatment of pulmonary fibrosis, lung cancer, and other related ailments. However, the function of PTN in the treatment of PH has not been studied. PurposeThis study aimed to evaluate the anti-proliferation and pro-apoptosis effects of PTN on PH and investigate its potential mechanisms. MethodsAn in vivo hypoxia-induced pulmonary hypertension (HPH) model was established by maintaining male rats in a hypoxia chamber (10% O2) for 3 weeks, and PTN was intraperitoneally administered at the dose of 10 or 30 mg/kg. We assessed the impact of PTN on mean pulmonary arterial pressure (mPAP), pulmonary vascular remodeling, and right ventricular hypertrophy. In vitro, we evaluated hypoxia-induced cellular proliferation, migration, and apoptosis of rat PASMCs. Proteins related to the STAT3 signaling axis were analyzed by western blotting and immunofluorescence assays. Recovery experiments were performed using the STAT3 activator, colivelin TFA. ResultsPTN significantly alleviated the symptoms of HPH rats by attenuating pulmonary arterial remodeling. It also prevented the proliferation and migration of PASMCs. PTN also induced the apoptosis of PASMCs. PTN could directly interact with STAT3 and markedly inhibited STAT3 phosphorylation and nuclear translocation. In vitro, and in vivo experiments demonstrated that overexpression of STAT3 partially suppressed the effect of PTN. ConclusionOur study indicated that PTN alleviated hypoxia-induced pulmonary hypertension in rats by suppressing STAT3 activity.

Levels of aryl hydrocarbon receptor nuclear translocator in lung tissue of children with congenital heart disease pulmonary hypertension and its effect on proliferation and migration of pulmonary artery smooth muscle cells

Objective To observe the levels of aryl hydrocarbon receptor nuclear translocator (ARNT) in lung tissue of children with congenital heart disease (CHD) pulmonary artery hypertension (PAH) and its effect on proliferation and migration of human pulmonary artery smooth muscle cells (HPASMCs), and to investigate the action mechanism of ARNT in the pathogenesis of CHD-PAH. Methods Sixty patients with CHD ventricular septal defect-associated PAH were selected as CHD-PAH group and 60 children with CHD ventricular septal defect without PAH were selected as CHD group (CHD group) in our hospital. There were no significant difference in age and gender between the two groups. HPASMCs were divided into normoxia group and hypoxia group, which were induced by normoxia and hypoxia respectively. HPASMCs were divided into blank control group (BC group), negative control group (NC group) and siR-ARNT group. The cells in the siR-ARNT group were transfected with ARNT-shRNA lentivirus, and those in the NC group were transfected with negative control lentivirus. The cells in the BC group were not transfected. The expression levels of ARNT protein and mRNA in lung tissue and cells were detected by Western blotting and reverse transcription-polymerase chain reaction (RT-PCR). The cell proliferation ability was determined by the cell counting kit-8 (CCK-8) method. Transwell and scratch assays were used to measure cell migration ability. SPSS 20.0 software was used for analysis. The test methods were t test and analysis of variance. Results The expression levels of ARNT protein and mRNA in lung tissue of CHD-PAH group (0.53±0.06 and 2.36±0.17) were significantly higher than those in CHD group (0.09±0.02, 1.00±0.12, t=53.889 and 50.626, P 0.05). Conclusion The ARNT levels in lung tissue of children with CHD-PAH are elevated. ARNT may participate in the development of CHD-PAH by affecting the proliferation and migration of HPASMCs. Key words: Congenital heart disease; Pulmonary hypertension; Aryl hydrocarbon receptor nuclear translocation protein; Pulmonary artery smooth muscle cells; Proliferation; Migration

Changes in expression of Talin1 and F-actin during serum-induced proliferation of pulmonary artery smooth muscle cells of rats with hepatopulmonary syndrome

Objective To evaluate the changes in the expression of Talin1 and F-actin during serum-induced proliferation of pulmonary artery smooth muscle cells (PASMCs) of rats with hepatopulmonary syndrome (HPS). Methods Twenty healthy male Sprague-Dawley rats, weighing 220-250 g, were used for producing HPS by chronic ligation of the common bile duct.Blood samples from the abdominal aorta were collected to prepare serum.Primarily cultured PASMCs obtained from rats were seed in 6- or 96-well plates and divided into 2 groups using a random number table method: control group (group C) and HPS group (group HPS), with 24 wells in each group (for 6-well plates) or with 30 wells in each group (for 96-well plates). In C and HPS groups, normal rat serum or HPS rat serum were added, respectively, with the final concentration of 5%.At 24, 48 and 72 h of incubation, the expression of Talin1, F-actin and G-actin was determined by Western blot, the F-actin/G-actin ratio was calculated, and the proliferation of PASMCs was measured by 3H-TdR incorporation and CCK-8 assays. Results Compared with group C, the proliferation of PASMCs was significantly enhanced, the expression of Talin1 was up-regulated, and the F-actin/G-actin ratio was increased in group HPS (P<0.05). The proliferation of PASMCs was gradually enhanced, the expression of Talin1 was gradually up-regulated, and the F-actin/G-actin ratio was gradually increased with the prolonged incubation time in group HPS (P<0.05). Conclusion The mechanism by which the HPS rat serum induces proliferation of PASMCs may be related to up-regulating the expression of Talin1 and F-actin. Key words: Hepatopulmonary syndrome; Myocytes, smooth muscle; Pulmonary artery; Cell proliferation; Talin; Actins

Effect of emodin on the proliferation and migration of hypoxia pulmonary artery smooth muscle cells

Objective To observe the inhibitory effect of emodin on the proliferation and migration of pulmonary artery smooth muscle cells. Methods Primary cultured human pulmonary arterial smooth muscle cells (HPASMC) were cultured in a routine manner to establish an hypoxic cell model. Emodin at different concentrations (0, 5, 10, 15 and 20 μmol/L) 48 and 72 h later, the proliferation and migration of hypoxic pulmonary artery were detected by methyl thiazol tetrazolium (MTT) assay and Transwell invasion assay. Western blotting assay was used to determine the expression of p38 protein in hypoxia HPASMC induced by emodin. Results Emodin inhibited the proliferation and migration of hypoxic HPASMC in a time-and concentration-dependent manner. When the concentration was 20 μmol/L, the effect was the most significant, and the inhibitory rates at 12, 24, 48 and 72 h were (53.46±1.81)%, (61.32±2.69)%, (76.34±3.05)% and (84.43±3.18)%, respectively. (68.90±8.49), (46.10±5.63), (27.56±5.38) in the Transwell experimental group (5, 10, 15 and 20 μmol/[(12.61±3.68)] compared with the control group [(88.59±8.56)]. Compared with the control group, the experimental group p38 protein expression was reduced (P=0.001). Conclusion Emodin can significantly inhibit the proliferation and migration of human pulmonary artery smooth muscle cells under hypoxic conditions and down-regulate the expression of p38 protein. Key words: Emodin; Pulmonary artery smooth muscle cells; Proliferation; Migration

Effects of T-type calcium channel inhibitors on monocrotaline-induced pulmonary arterial hypertension in rats

Objective To investigate the effects of T-type calcium channel inhibitors (ProTx-1, micromolar Ni2+ and Mibefradil) on Monocrotaline(MCT)-induced pulmonary arterial hypertension (PAH) in rats. Methods Forty male Sprague-Dawley rats were randomly divided into 5 groups: normal control group, MCT group, ProTx-1 group, micromolar Ni2+ group and Mibefradil group (8 cases in each group). The right ventricular systolic pressure (RVSP), the right ventricular hypertrophy index (RVHI), and the index of pulmonary vascular remodeling(MA%) were measured on day 28 after MCT-treatment.Western blot was used to detect the expression of proliferating cell nuclear antigen(PCNA) and Cleaved Caspase-3 in pulmonary artery. Results (1)RVSP and RVHI in MCT group were significantly higher than those in the other 4 groups (F=21.55, P 0.05). (2)MA% in normal control group[(23.43±1.95)%] was lower than that in MCT group[(80.42±4.30)%], ProTx-1 group[(60.35±3.83)%], micromolar Ni2+ group[(62.44±3.81)%] and Mibefradil group[(58.66±4.23)%](F=216.2, P 0.05), however, they were all signi-ficantly lower than that in MCT group.(3)The expression of PCNA in MCT group was higher than that in normal control group, meanwhile, 3 intervention groups were significantly lower than that in MCT group.The expression of Cleaved Caspase-3 in MCT group was higher than that in normal control group, nevertheless, 3 intervention groups showed no significant changes compared with MCT group, respectively. Conclusions T-type calcium channel inhibitors could ameliorate the progression of MCT-PAH in rats, mainly through suppressing the proliferation of pulmonary artery smooth muscle cells. Key words: Pulmonary arterial hypertension; Monocrotaline; Voltage dependent calcium channel; Proliferation; Apoptosis

Relevant factors of pulmonary arterial smooth muscle cells proliferation and pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a disease of unknown etiology that leads to a progressive increase in pulmonary vascular resistance (PVR), if untreated, ultimately right heart failure and high mortality.It is concerted pulmonary vascular contraction and vascular remodeling are the 2 main courses of physiology and pathology leading to PAH, especially the significant role of proliferation of pulmonary arterial smooth muscle cells.A lot of relevant factors are revealed to take a participation into regulating the proliferation of pulmonary arterial smooth muscle cells and finally PAH. Key words: Pulmonary arterial smooth muscle cell; Cell proliferation; Relevant factor; Pulmonary arterial hypertension

Impact and mechanism of Captopril on the pulmonary arterial hypertension model induced by chronic hypoxia in rats

Objective To investigate the effects of Captopril on the hemodynamic changes,the proliferation of pulmonary arterial smooth muscle cells and phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) mRNA and protein expression in pulmonary arterial hypertension (PAH) induced by chronic hypoxia in rats.Methods Thirty male SD rats were randomly divided into control group (n =10),PAH group (n =10) and Captopril group (n =10).The rats in PAH group and Captopril group were treated with chronic hypoxia,and those in Captopril group were given intragastric administration of Captopril 100 mg/(kg·day),while other groups were given the intragastric administration of the same volume of normal saline.The rats in each group were sacrificed at the end of experiment (28th day).The hemedynamics of PAH was measured and the morphological parameters relevant to the proliferation of pulmonary arterial smooth muscle cells were observed.The reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting were used to detect the expression levels of PI3K/Akt mRNA and protein in the pulmonary tissues.Results The PAH group had significantly higher mPAP [(38.3 ± 2.3) mm Hg (1 mm Hg =0.133 kPa)],sRVP [(57.1 ±4.8) mmHg],RV/(LV +S) ratio [(0.47±0.03)％],and RMT [(53.9-±5.9)％] than in control group (all P ＜0.05).The levels of PI3K/Akt mRNA and protein expression were significantly up-regulated in PAH group as compared with control group (P ＜ 0.05).The Captopril group had significantly lower mPAP [(16.5 ±0.6) mm Hg],sRVP [(22.8 ±0.7) mm Hg],RV/(LV + S) ratio [(0.35 ± 0.03) ％],and RMT [(30.5 ± 3.8) ％] (all P ＜ 0.05) than in control group.The levels of PI3K/Akt mRNA and protein expression were significantly down-regulated in Captopril group as compared with control group (P ＜ 0.05).There was no significant differences in mPAP,sRVP,RV/(LV + S),and the expression levels of PI3K/Akt mRNA and protein between control group and Captopril group (all P ＞ 0.05).Conclusion Captopril inhibits the pathological progress of the PAH,which may be contributed to the inhibition of up-regulation of the PI3K/Akt in the rats with PAH induced by chronic hypoxia. Key words: Captopril; Phosphatidylinositol 3 kinase/protein kinase B ; Pulmonary hypertension

GW24-e3078 Vascular peroxidase 1 is involved in pulmonary arterial hypertension via mediate pulmonary arterial smooth cells proliferation

ObjectivesHypoxia could induce pulmonary arterial smooth muscle cells (PASMCs) proliferation via hydrogen peroxide (H2O2)-induced oxidative stress. Our previous research had demonstrated that vascular peroxidase 1 (VPO1) could utilise hydrogen peroxide...

Targeting Epigenetic Changes for the Reprogramming of Vascular Walls in Pulmonary Arterial Hypertension, the Role of Histone Deacetylases and their Inhibitors

Pulmonary arterial hypertension (PAH) is a disease of the pulmonary vasculature as defined by an ele vated pulmonary vascular resistance (PVR) leading to a failure of the right heart and ultimately death [1]. Although the overall 5-year survival for PAH has significantly increased in the past years, none of the approved therapies have shown an ability to cure the disease. Current available treatments are limited, expensive, and often associated with significant, side effects. As such, furthering our understanding of the mechanisms underlying PAH development is important to improve patient management and outcomes. A number of evidence have shown that cellular and molecular changes occur in the pulmonary arteries in response to chronic hypoxic exposure [1,2], and primary lung diseases including chronic obstructive pulmonary disease, cystic fibrosis, etc. are associated with the presence of chronic hypoxia. In PAH, the pulmonary arteries (PAs) exhibit pathological proliferative vascular remodeling related to medial and adventitial thickening of pulmonary arterial walls. The excessive proliferation of smooth muscle cells as well as the accumulation of fibroblasts and myofibroblasts plays an important role in the medial and adventitial thickening respectively. Epigenetics describes that heritable changes in gene expression or cellular phenotype are caused by mechanisms other than changes in the underlying DNA sequence. Histone modification is one of the predominant epigenetic phenomena. It selectively modulates gene expressions that control many biological processes including cell proliferation. Histone deacetylases (HDACs) remove an acetyl group from lysine residues of target proteins to regulate a number of cellular processes. There are 18 HDAC enzymes which are identified and grouped into four classes. Class I, II, and IV share sequence similarity and are dependent on Zn2+ for enzymatic activity, whereas the class III sirtuins act through a distinct NAD+-dependent mechanism. Pulmonary vascular remodeling (PAR) is a characteristic pathological change of PAH. The development of PAR involves all layers of the vessel wall. It has been reported that adventitial fibroblasts in the pulmonary hypertensive vessel wall exhibit a hyper proliferative, inflammatory, and invasive phenotype. Hypoxia-induced PAR is characterized by the emergence of a distinct adventitial fibroblast population. This population exhibits a constitutively activated, pro-inflammatory phenotype that is capable of inducing recruitment, retension and pro-inflammatory activation of monocytes/microphages. Stenmark’s group has recently demonstrated that pulmonary adventitial fibroblasts from chronically hypoxic hypertensive calves (PH-Fibs) expressed a constitutive and persistent proinflammatory phenotype. The proinflammatory phenotype of PH-Fibs was associated with epigenetic alterations as demonstrated by increased activity of HDACs. Importantly, a reversal of this proinflammatory phenotype can be achieved with the use of class I HDAC inhibitors [3]. Another hallmark feature of PAR is excessive smooth muscle cell proliferation leading to medial thickening. In our high altitude longterm (LTH) sheep model, an obvious pulmonary arterial remodeling was observed. We found that the level of global histone acetylation was significantly decreased in LTH fetus PAs, and it was accompanied by the loss of the cyclin-dependent kinase inhibitor, p21, as opposed to the control. The treatment of the pulmonary arterial smooth cells (PASMC), isolated from LTH fetal lung, with a class I HDAC inhibitor markedly decreased their proliferation rate in part due to an increased expression of p21 at both the RNA and protein level. Interestingly, a class II HDAC inhibitor also showed an inhibitory effect on cell proliferation when used with a relative higher concentration. However, a class III inhibitor exhibited no effect on cell proliferation [4]. These findings suggested that epigenetic alterations caused by chronic hypoxia led to fetal PASMC proliferation and vessel remodeling as associated with vascular proliferative disease, and that this process is regulated by p21. This is consistent with a previous study which showed that a p53 gene deficiency decreased p21 expression levels that eventually resulted in hypoxia-induced PAH and vascular remodeling in mice [5]. The above studies correlate with in vivo data showing that small molecules (MGCD0103 and MS-275) that selectively block class I HDACs reduce hypoxia-induced PAH in a manner that associates with a blunted medial thickening of PAs and a reduced proliferation of PASMC in these vessels [6]. These findings support a unique role for HDACs as important targets for PAH, and highlight the potential of isoform-specific HDAC inhibitors for the treatment of cardiovascular diseases.

Mechanisms of focal adhesion kinase in the proliferation of human pulmonary artery smooth cells under hypoxia

To explore the mechanisms of focal adhesion kinase (FAK) in the proliferation of human pulmonary artery smooth muscle cells (HPASMCs) under hypoxia. Cultured HPASMCs were passively transfected with FAK oligonucleotides (ODNS) and under normoxia or hypoxia condition. They were divided into four groups: normoxia without fibronectin (FN), normoxia with FN, hypoxia without FN, hypoxia with FN in vitro respectively. Cytoplasmic FAK, Grb2 and paxillin were observed simultaneously by immunoprecipitation and Western blot. In addition, the expressions of cytoplasmic FAK, Grb2 and paxillin were detected by immunocytochemical staining. Immunoprecipitation and Western blot demonstrated that cytoplasmic expressions of FAK, Grb2 and paxillin in HPASMCs increased in hypoxia with FN from 43.4 ± 1.4, 69.7 ± 1.9, 59.3 ± 1.6 to 35.7 ± 1.2, 48.7 ± 1.3, 33.2 ± 1.8 at 1.5 h (all P < 0.05), from 41.3 ± 1.3, 71.3 ± 1.5, 59.4 ± 1.8 to 41.3 ± 1.3, 50.2 ± 1.7, 38.9 ± 1.9 at 24 h respectively (P < 0.01, P < 0.05, P < 0.05). Immunocytochemistry staining showed that the cytoplasmic expressions of FAK, Grb2 and paxillin were enhanced in hypoxia with FN versus normoxia with FN. There were significant differences. Hypoxia can induce the activation of cytoplasmic FAK, Grb2 and paxillin so as to regulate the migration, survival and proliferation of HPASMCs.

The expression variations of connective tissue growth factor and cyclinD1 in pulmonary vascular remodeling induced by cigarette smoke in rats

To investigate the expression variations of connective tissue growth factor (CTGF) and cyclin D1 in pulmonary vasculature in rats exposed to cigarette smoke and their roles in pulmonary vascular remodeling. Twenty-four male Wistar rats were randomly divided into 4 groups: 1 control group (C group) and 3 smoke exposure groups (S2w, S4w, S8w group). Arterial partial pressure of oxygen was measured. Pulmonary artery remodeling was observed by Hematoxylin-Eosin staining and the percentage of muscularised small pulmonary arteries. Immunohistochemistry methods were performed to observe CTGF and cyclin D1 expressions in pulmonary artery smooth muscle. Real time quantitative RT-PCR and Western blot analysis were used for detection of mRNA and protein expressions in pulmonary artery smooth muscle. There was no significant difference in arterial partial pressure of oxygen among all groups. The percentage of muscularised small vessels and W/T were significantly increased in S2w, S4w and S8w group compared to control group (P < 0.05). Compared to control group, significant increases of CTGF and cyclinD1 expressions in smoke exposure groups were observed (P < 0.05). The expressions of CTGF and cyclinD1 were significantly positively correlated with the severity of pulmonary vascular muscularization, and there was statistically positive correlation between the expression of CTGF and cyclinD1. CTGF and cyclinD1 expressions significantly were upregulated in pulmonary arteries from rats exposed to cigarette smoke (2-8w) and there was a significant positive correlation between their expressions. Their expression variations may be associated with abnormal proliferation of pulmonary artery smooth muscle cells induced by cigarette smoke.