Mufangji tang ameliorates pulmonary arterial hypertension through improving vascular remodeling,inhibiting inflammatory response and oxidative stress,and inducing apoptosis

Background:Mufangji tang(MFJT)is composed of Ramulus Cinnamomi,Radix Ginseng,Cocculus orbiculatus(Linn.)DC.,and Gypsum.In clinical settings,MFJT has been effectively employed in addressing a range of respiratory disorders,notably including pulmonary arterial hypertension(PAH).However,the mechanism of action of MFJT on PAH remains unknown.Methods:In this study,a monocrotaline-induced PAH rat model was established and treated with MFJT.The therapeutic effects of MFJT on PAH rat model were evaluated.Network pharmacology was conducted to screen the possible targets for MFJT on PAH,and the molecular docking between the main active components and the core targets was carried out.The key targets identified from network pharmacology were tested.Results:Results showed significant therapeutic effects of MFJT on PAH rat model.Analysis of network pharmacology revealed several potential targets related to apoptosis,inflammation,oxidative stress,and vascular remodeling.Molecular docking showed that the key components were well docked with the core targets.Further experimental validation results that MFJT treatment induced apoptosis(downregulated Bcl-2 levels and upregulated Bax levels in lung tissue),inhibited inflammatory response and oxdative stress(decreased the levels of IL-1β,TNF-α,inducible NOS,and malondialdehyde,and increased the levels of endothelial nitric oxide synthase,nitric oxide,glutathione and superoxide dismutase),reduced the proliferation of pulmonary arterial smooth muscle cells(downregulated ET-1 andβ-catenin levels and ERK1/2 phosphorylation,increased GSK3βlevels).Conclusion:Our study revealed MFJT treatment could alleviate PAH in rats via induction of apoptosis,inhibition of inflammation and oxidative stress,and the prevention of vascular remodeling.

CircPMS1 promotes proliferation of pulmonary artery smooth muscle cells,pulmonary microvascular endothelial cells,and pericytes under hypoxia

Background:Circular RNAs(circRNAs)have been recognized as significant regulators of pulmonary hypertension(PH);however,the differential expression and function of circRNAs in different vascular cells under hypoxia remain unknown.Here,we identified co-differentially expressed circRNAs and determined their putative roles in the proliferation of pulmonary artery smooth muscle cells(PASMCs),pulmonary microvascular endothelial cells(PMECs),and pericytes(PCs)under hypoxia.Methods:Whole transcriptome sequencing was performed to analyze the differential expression of circRNAs in three different vascular cell types.Bioinformatic analysis was used to predict their putative biological function.Quantitative real-time polymerase chain reaction,Cell Counting Kit-8,and EdU Cell Proliferation assays were carried out to determine the role of circular postmeiotic segregation 1(circPMS1)as well as its potential sponge mechanism in PASMCs,PMECs,and PCs.Results:PASMCs,PMECs,and PCs exhibited 16,99,and 31 differentially expressed circRNAs under hypoxia,respectively.CircPMS1 was upregulated in PASMCs,PMECs,and PCs under hypoxia and enhanced the proliferation of vascular cells.CircPMS1may upregulate DEP domain containing 1(DEPDC1)and RNA polymerase II subunit D expression by targeting microRNA-432-5p(miR-432-5p)in PASMCs,upregulate MAX interactor 1(MXI1)expression by targeting miR-433-3p in PMECs,and upregulate zinc finger AN1-type containing 5(ZFAND5)expression by targeting miR-3613-5p in PCs.Conclusions:Our results suggest that circPMS1 promotes cell proliferation through the miR-432-5p/DEPDC1 or miR-432-5p/POL2D axis in PASMCs,through the miR-433-3p/MXI1 axis in PMECs,and through the miR-3613-5p/ZFAND5 axis in PCs,which provides putative targets for the early diagnosis and treatment of PH.

Calpain mediated pulmonary vascular remodeling in hypoxia induced pulmonary hypertension

OBJECTIVE To explore the role of calpain in in pulmonary vascular remodeling in hypoxia induced pulmonary hypertension and the underlying mechanism.METHODS Sprague-Dawley rats were randomly divided into hypoxia group and normoxia control group.Right ventricular systolic pressure(RVSP)and mean pulmonary artery pressure(m PAP)were monitored by the method of right external jugular vein cannula.Right ventricular hypertrophy index was expressed as the ratio of right ventricular weight to left ventricular weight(left ventricle plus septum weight).Level of calpain-1,calpain-2and calpain-4 m RNA in pulmonary artery trunk were determined by real-time PCR.Expression of calpain-1,calpain-2 and calpain-4 protein was determined by Western Blot.Primary rat pulmonary arterial smooth muscle cells(PASMCs)were divided into 4 groups:normoxia control group,normoxia+MDL28170 group,hypoxia group and hypoxia+MDL28170 group.Cell proliferation was detected by MTS and flow cytometry.Level of Ki-67 and PCNA m RNA were determined by real-time PCR.RESULTS RVSP,m PAP and right ventricular remodeling index were significantly higher in the hypoxia group than those in the normoxia group.In the hypoxia group,pulmonary vascular remodeling occurred,and the expression of calpain-1,calpain-2 and calpain-4 m RNA and protein expression was increased in the pulmonary artery.MDL28170 significantly inhibited hypoxia-induced proliferation of PASMCs accompanied with decreased Ki-67and PCNA m RNA expression.CONCLUSION Calpain mediated vascular remodeling via promoting proliferation of PASMCs in hypoxia induced pulmonary hypertension.

The role of HSPB1 and ectopic F1Fo-ATPase interaction in hypoxia pulmonary hypertension vascular adventitial vasa vasorum remodeling

OBJECTIVE To investigate the role of adventitial vasa vasorum in artery remodeling during the process of pulmonary artery hypertension(PAH),we checked the small heat shock protein 27/25(HSPB1)whether involved in pathological basis of vascular remodeling.METHODS We explored the potential role of HSPB1 interacts with ectopic F1Fo-ATPase in the pulmonary vascular remodeling,investigate its effects on the endothelium cell dynamic,and further reveal its possible molecular mechanisms using hypoxic pulmonary hypertension rat model,transgenic mice and pulmonary adventitial vasa vasorum endothelial cell culture in vitro.RESULTS Our studies have shown that HSPB1 improves adventitial vasa vasorum angiogenesis and remodeling.We found that hypoxia induces-HSPB1 upregulation and HSPB1 interact with ectopic F1Fo-ATPase modulate adventitial vasa vasorum endothelial cell proliferation,migration and tube formation.And the inhibition of HSPB1can reverse the vascular inflammation and fibrosis amazingly.CONCLUSION Adventitial vasa vasorum plays an important role in vascular remodeling,and small heat shock protein 27/25 was involved in a variety of diseases during the development of PAH,which could an efficient therapeutic targets and prevention strategy for PAH clinical.

Hypoxia promotes pulmonary vascular remodeling via HIF-1α to regulate mitochondrial dynamics

Background Increasing research suggests that mitochondrial defect plays a major role in pulmonary hypertension(PH) pathogenesis. Mitochondrial dynamics and quality control have a central role in the maintenance of the cell proliferation and apoptosis balance. However, the molecular mechanism underlying of this balance is still unknown. Methods To clarify the biological effects of hypoxic air exposure and hypoxia-inducible factor-1α(HIF-1α) on pulmonary arterial smooth muscle cell(PASMC) and pulmonary arterial hypertension rats, the cells were cultured in a hypoxic chamber under oxygen concentrations. Cell viability, reactive oxygen species level, cell death, mitochondrial morphology, mitochondrial membrane potential, mitochondrial function and mitochondrial biosynthesis, as well as fission-and fusion-related proteins, were measured under hypoxic conditions. In addition, rats were maintained under hypoxic conditions, and the right ventricular systolic pressure, right ventricular hypertrophy index and right ventricular weight/body weight ratio were examined and recorded. Further, we assessed the role of HIF-1α in the development and progression of PH using HIF-1α gene knockdown using small interfering RNA transfection. Mdivi-1 treatment was performed before hypoxia to inhibit dynamin-related protein 1(Drp1). Results We found that HIF-1α expression was increased during hypoxia, which was crucial for hypoxia-induced mitochondrial dysfunction and hypoxia-stimulated PASMCs proliferation and apoptosis. We also found that targeting mitochondrial fission Drp1 by mitochondrial division inhibitor Mdivi-1 was effective in PH model rats. The results showed that mitochondrial dynamics were involved in the pulmonary vascular remodeling under hypoxia in vivo and in vitro. Furthermore, HIF-1α also modulated mitochondrial dynamics in pulmonary vascular remodeling under hypoxia through directly regulating the expression of Drp1. Conclusions In conclusion, our data suggests that abnormal mitochondrial dynamics could be a marker for the early diagnosis of PH and monitoring disease progression. Further research is needed to study the signaling pathways that govern mitochondrial fission/fusion in PH.

The Role of Endogenous Carbon Monoxide in the Hypoxic Vascular Remodeling of Rat Model of Hypoxic Pulmonary Hypertension

We investigated the expression of heme oxygenase 1 (HO 1) gene and production of endogenous carbon monoxide (CO) in the rat lung tissue at different time points of chronic hypoxic pulmonary hypertension and the effect of hemin on the expression of HO 1 gene and pulmonary hypertension. A rat model of hypoxic pulmonary hypertension was recreated by exposure to intermittent normobaric hypoxic environment (10 % O 2). Reverse transcriptase polymerase chain reaction (RT PCR) was performed to determine the level of HO 1 mRNA in the rat lung tissue and double wave length spectrophotometry was used to evaluate the quantity of COHb in arterial blood. Cardiac catheterization was employed to measure the right ventricular systolic pressure (RVSP) and HE staining was performed in dissected lung tissue to observe the pathological changes of the intra acinar pulmonary arteries (IAPA). It was found that (1) There was a low level of HO 1 mRNA in normal rat lung tissue, but the level of HO 1 mRNA increased by 2-4 times in the lung tissue of hypoxic rats ( P <0.01). The quantity of COHb was 2-3 times those of control group ( P <0.01 or P <0.05). These were accompanied by the increased of RVSP and the thickened IAPA; (2) Hemin could keep the HO 1 mRNA and COHb in the hypoxic rat lung tissue at a high level, and partially suppressed the increase of rat RVSP, thereby ameliorating the pathological changes of IAPA. In conclusion, the upregulation of the expression of HO 1 gene and production of CO in the rat lung of hypoxic pulmonary hypertension plays a role of inhibition in the development of hypoxic pulmonary hypertension. Hemin has a therapeutic effect on hypoxic pulmonary hypertension.

Effects of serum Fractalkine on vascular remodeling and oxidative stress activation in patients with COPD complicated by pulmonary heart disease

Objective: To study the effects of serum Fractalkine on vascular remodeling and oxidative stress activation in patients with COPD complicated by pulmonary heart disease. Methods:Patients who were hospitalized in Chongqing Armed Corps Police Hospital due to COPD between June 2014 and April 2017 were selected, the patients with COPD alone were included in COPD group, and the patients with COPD complicated by pulmonary heart disease were included in COPD+PHD group;healthy volunteers who underwent physical examination during the same period were selected as the control group of the study. The serum was collected to determine the contents of Fractalkine, vascular remodeling indexes and oxidative stress indexes. Results: Serum Fractalkine, ANG-2, MMP2, MMP9, VEGF, FGF2, Nogo-B, ET-1 and MDA contents of COPD+PHD group and COPD group were higher than those of control group whereas T-AOC contents were lower than that of control group;serum Fractalkine, ANG-2, MMP2, MMP9, VEGF, FGF2, Nogo-B, ET-1 and MDA contents of COPD+PHD group were higher than those of COPD group whereas T-AOC content was lower than that of COPD group. Serum ANG-2, MMP2, MMP9, VEGF, FGF2, Nogo-B, ET-1 and MDA contents of COPD+PHD group of patients with high Fractalkine content were significantly higher than those of COPD+PHD group of patients with low Fractalkine content whereas T-AOC content was lower than that of COPD+PHD group of patients with low Fractalkine content. Conclusion: The increase of serum Fractalkine in patients with COPD complicated by pulmonary heart disease can aggravate the vascular remodeling and promote the oxidative stress activation.

Role of ROS/Kv/HIF Axis in the Development of Hypoxia-Induced Pulmonary Hypertension

Hypoxic pulmonary hypertension (HPH) is a common complication in patients with chronic obstructive pulmonary disease (COPD), sleep-disordered breathing, or dwellers in high altitude. The exact mechanisms underlying the development of HPH still remain unclear. Reactive oxygen species (ROS),hypoxia inducible factors (HIF), and potassium channels (KV) are believed as the main factors during the development of HPH. We propose that the “ROS/Kv/HIF axis” may play an important initiating role in the development of HPH. Being formed under a hypoxic condition, ROS affects the expression and function of HIFs or KV, and consequently triggers multiple downstream signaling pathways and genes expression that participate in promoting pulmonary vasoconstriction and arterial remodeling. Thus, further study determining the initiating role of “ROS/Kv/HIF axis” in the development of HPH could provide theoretic evidences to better understand the underlying mechanisms of HPH, and help identify new potential targets in the treatment of HPH.

Vascular Metabolic Mechanisms of Pulmonary Hypertension

Pulmonary hypertension(PH)is a severe and progressive disease characterized by increased pulmonary vascular resistance leading to right heart failure and death.In PH,the cellular metabolisms including those of the three major nutrients(carbohydrate,lipid and protein)are aberrant in pulmonary vascular cells.Glucose uptake,glycolysis,insulin resistance,sphingolipid S1P,PGE2,TXA2,leukotrienes and glutaminolysis are upregulated,and phospholipid-prostacyclin and L-arginine-nitric oxide pathway are compromised in lung vascular cells.Fatty acid metabolism is disordered in lung endothelial cells and smooth muscle cells.These molecular mechanisms are integrated to promote PH-specific abnormal vascular cell proliferation and vascular remodeling.This review summarizes the recent advances in the metabolic reprogramming of glucose,fatty acid,and amino acid metabolism in pulmonary vascular remodeling in PH and the mechanisms for how these alterations affect vascular cell fate and impact the course of PH.

Effects of low ambient temperatures and dietary vitamin C supplementation on pulmonary vascular remodeling and hypoxic gene expression of 21-d-old broilers

The objective of this study was to evaluate the effects of low ambient temperature （LAT） and dietary vitamin C （VC） sup- plementation on pulmonary vascular remodeling （PVR） and the relative expression of hypoxia inducible factor-la （HIF-la）, vascular endothelial growth factor （VEGF） and its receptor 2 （VEGFR-2） mRNA of lungs in 21-d-old broilers. 400 1-d-old male Cobb broilers were assigned randomly to 4 treatments as follows for 21 d： 1 ） LAT and a basal diet; 2） LAT and a basal diet supplemented with 1 000 mg kg-1 VC （LAT＋VC）; 3） normal ambient temperature （NAT） and a basal diet; 4） NAT and a basal diet supplemented with 1 000 mg kg-1 VC （NAT＋VC）. Each treatment was composed of 10 replicates of 10 birds per replicate. Samples of lung were collected after the broilers were killed at d 21. LAT increased the ratio of vessel wall area to vessel total area （WA/TA, %） and mean media thickness in pulmonary arterioles （mMTPA, %） （P〈0.05）. Dietary VC supplementation decreased mMTPA （P〈0.05）, but had no effect on the WA/TA. LAT increased （P〈0.05） the relative mRNA expression of HIF-la, VEGF and VEGFR-2, while adding VC to the diet could decrease （P〈0.05） their relative mRNA expression. A significant positive correlation existed between the level of VEGF mRNA expression and the value of WA/WT （P〈0.05） or mMTPA （P〈0.05）. These results suggested LAT resulted in pulmonary vascular remodeling, and the increase of HIF-la, VEGF and VEGFR-2 mRNA expression, and dietary VC supplementation can alleviate pulmonary vascular remodeling in broiler by affecting these gene expression.

Animal models of pulmonary hypertension due to left heart disease

Pulmonary hypertension due to left heart disease(PH-LHD) is regarded as the most prevalent form of pulmonary hypertension(PH). Indeed, PH is an independent risk factor and predicts adverse prognosis for patients with left heart disease(LHD). Clinically, there are no drugs or treatments that directly address PH-LHD, and treatment of LHD alone will not also ameliorate PH. To target the underlying physiopathological alterations of PH-LHD and to develop novel therapeutic approaches for this population, animal models that simulate the pathophysiology of PH-LHD are required. There are several available models for PH-LHD that have been successfully employed in rodents or large animals by artificially provoking an elevated pressure load on the left heart, which by transduction elicits an escalated pressure in pulmonary artery. In addition, metabolic derangement combined with aortic banding or vascular endothelial growth factor receptor antagonist is also currently applied to reproduce the phenotype of PH-LHD. As of today, none of the animal models exactly recapitulates the condition of patients with PH-LHD. Nevertheless, the selection of an appropriate animal model is essential in basic and translational studies of PH-LHD. Therefore, this review will summarize the characteristics of each PH-LHD animal model and discuss the advantages and limitations of the different models.

ADAR1 regulates vascular remodeling in hypoxic pulmonary hypertension through N1-methyladenosine modification of circCDK17

Pulmonary hypertension(PH)is an extremely malignant pulmonary vascular disease of unknown etiology.ADAR1 is an RNA editing enzyme that converts adenosine in RNA to inosine,thereby affecting RNA expression.However,the role of ADAR1 in PH development remains unclear.In the present study,we investigated the biological role and molecular mechanism of ADAR1 in PH pulmonary vascular remodeling.Overexpression of ADAR1 aggravated PH progression and promoted the proliferation of pulmonary artery smooth muscle cells(PASMCs).Conversely,inhibition of ADAR1 produced opposite effects.High-throughput whole transcriptome sequencing showed that ADAR1 was an important regulator of circRNAs in PH.CircCDK17 level was significantly lowered in the serum of PH patients.The effects of ADAR1 on cell cycle progression and proliferation were mediated by circCDK17.ADAR1 affects the stability of circCDK17 by mediating A-to-I modification at the A5 and A293 sites of circCDK17 to prevent it from mlA modification.We demonstrate for the first time that ADAR1 contributes to the PH development,at least partially,through m1A modification of circCDK17 and the subsequent PASMCs proliferation.Our study provides a novel therapeutic strategy for treatment of PH and the evidence for circCDK17 as a potential novel marker for the diagnosis of this disease.

The effect of bone marrow mesenchymal stem cell transplantation on hypoxic pulmonary hypertension in rats

Objective:To study the influence of bone marrow mesenchymal stem cells(MSCs)transplantation on hypoxic pulmonary hypertension(HPH)in rats.Methods:MSCs in SD rats were separated,cultivated,identified in vitro,and labeled by the green fluorescence protein(GFP)adenovirus.Healthy male SD rats were randomly divided into four groups:normal control group(NC group)and HPH group,with eight rats in each group respectively;HPH+mesenchymal stem cell transplantation group(MSCs group)and HPH+vascular endothelial growth factor+mesenchymal stem cell transplantation group(VEGF+MSCs group),with twenty-four rats in each group respectively.In this experiment,intermittent normobaric hypoxia was employed to establish the pulmonary hypertension rat models,with stem cells transfected and transplanted.The mean pulmonary artery pressure(mPAP)was observed in rats to calculate the right ventricular hypertrophy index(RVHI);the morphological changes of pulmonary arterioles in each group of rats were observed under the microscope;the distribution and manifestation of MSCs fluorescently labeled by adenovirus transfection were observed in pulmonary arterioles under the fluorescence microscope at the set time points of 7 d,14 d and 28 d after the transplantation of stem cells.Results:For NC group,the mPAP(mmHg)was 15.5±1.5 at 28 d,while the mPAP in HPH,MSCs and VEGF+MSCs groups were 26.1±1.9,21.6±2.7 and 20.1±2.9 respectively which were apparently higher than that in NC group(p<.01).Compared with HPH group(p<.01),the mPAP was obviously decreased in MSCs and VEGF+MSCs groups.There was no significant difference between MSCs and VEGF+MSCs groups.At 28 d,RVHI for NC group was 0.28±0.02,while the RVHI in HPH,MSCs and VEGF+MSCs groups were 0.43±0.07,0.34±0.03 and 0.35±0.01 respectively which were apparently higher than that in NC group(p<.01).In comparison with HPH group,RVHI was significantly decreased in MSCs and VEGF+MSCs groups(p<.05).There was no significant difference between MSCs and VEGF+MSCs groups.For HPH group,at 28 d,pulmonary arterioles were apparently thickened,with luminal stenosis&obliteration and incomplete endothelial cells.Compared with HPH group,pulmonary arterioles in MSCs group became thinning,with the lumen unobstructed and the integrity of endothelial cells improved.The changes in the manifestation of MSCs and VEGF+MSCs groups were not significant.Conclusions:The transplantation of MSCs can improve the remodeling of pulmonary arterioles to partially reverse the progress of HPH;the combined transplantation of VEGF and MSCs doesn’t improve the effect of MSC transplantation.

低氧诱导因子-1在低氧性肺动脉高压中的研究进展

低氧性肺动脉高压(HPH)是由缺氧引起的肺动脉压力进行性升高的肺血管疾病。低氧诱导因子-1(HIF-1)是维持细胞氧稳态的核心转录因子,可促进细胞糖代谢模式的转变、调节细胞膜表面离子通道活性、调节肺血管收缩及舒张因子活性等,在HPH的发生和发展中具有重要作用。现对HIF-1及其下游信号分子在HPH发生和发展中的作用机制进行综述,有助于为HPH的治疗提供新的理论依据和治疗靶点。

基于PPAR-γ/NF-κB信号通路探讨肺心汤对野百合碱诱导肺动脉高压大鼠模型的作用及机制

目的基于过氧化物酶体增殖物激活受体γ/核因子κB(PPAR-γ/NF-κB)信号通路探讨肺心汤(黄芪、桃仁、红花、葶苈子、赤芍等)对野百合碱诱导肺动脉高压(PAH)大鼠模型的作用及机制。方法将48只雄性SD大鼠随机分为正常组、模型组、西地那非组(0.025 g·kg^(-1))及肺心汤低、中、高剂量组(11.7、23.4、46.8 g·kg^(-1))。采用单次腹腔注射野百合碱溶液(60 mg·kg^(-1))构建PAH大鼠模型。造模1 h后开始灌胃给药,每日1次,连续28 d。检测各组大鼠的血流动力学及超声心动图指标:右心室收缩压(RVSP)、平均肺动脉压(m PAP)、右心肥厚指数(RVHI)、肺动脉加速时间(PAAT)、肺动脉射血时间(PET)、三尖瓣环缩期位移(TAPSE)、右心室舒张末期内径(RVIDd)和右心室前壁厚度(RVAWT);采用HE染色法观察肺小动脉病理改变;免疫荧光法检测大鼠肺动脉中α平滑肌肌动蛋白(α-SMA)表达水平;ELISA法检测血浆白细胞介素1β(IL-1β)、IL-6、肿瘤坏死因子α(TNF-α)水平;免疫组化和Western Blot法检测PPAR-γ/NF-κB信号通路相关蛋白表达水平。结果与正常组相比,模型组大鼠的RVSP、m PAP、RVHI、RVIDd及RVAWT显著升高(P<0.01),PAAT、PAAT/PET、TAPSE均显著降低(P<0.01);肺小动脉血管壁明显增厚,肺小动脉管壁厚度占血管直径的百分比、血管壁面积占小动脉总横截面积的百分比均显著升高(P<0.01);肺动脉中α-SMA蛋白免疫荧光的阳性表达率显著升高(P<0.01);血浆IL-1β、IL-6、TNF-α水平显著升高(P<0.01);肺组织中的PPAR-γ蛋白阳性表达率显著降低(P<0.01),NF-κB蛋白阳性表达率显著升高(P<0.01);肺组织中PPAR-γ、IκB-α蛋白表达显著下调(P<0.01);p-NF-κB/NF-κB蛋白表达比值显著升高(P<0.01)。与模型组比较,各给药组大鼠的RVSP、m PAP、RVHI、RVIDd和RVAWT均显著降低(P<0.05,P<0.01),PAAT、PAAT/PET、TAPSE均显著升高(P<0.05,P<0.01);血管壁厚度明显降低,肺小动脉管壁厚度占血管直径的百分比、血管壁面积占小动脉总横截面积的百分比均显著降低(P<0.05,P<0.01);肺动脉中α-SMA蛋白免疫荧光的阳性表达率显著降低(P<0.05,P<0.01);血浆IL-1β、IL-6、TNF-α水平均显著降低(P<0.05,P<0.01);肺组织中的PPAR-γ蛋白阳性率表达显著升高(P<0.05,P<0.01),NF-κB蛋白阳性表达率显著降低(P<0.05,P<0.01);肺组织中PPAR-γ蛋白表达显著上调(P<0.05,P<0.01),p-NF-κB/NF-κB蛋白表达比值显著降低(P<0.01);肺心汤高剂量组大鼠肺组织中IκB-α蛋白表达显著上调(P<0.01)。结论肺心汤能改善野百合碱诱导的PAH大鼠肺动脉压力升高、右心功能障碍和肺血管重塑,其机制可能与调控PPAR-γ/NF-κB信号通路抑制炎症反应有关。

低氧性肺动脉高压大鼠肺内fractalkine的变化

目的探讨趋化因子fractalkine在低氧性肺动脉高压发病机制中的作用。方法将20只雄性SD大鼠随机分为对照组和低氧组,每组10只,低氧组以常压低氧建立肺动脉高压模型。以右心导管法检测平均肺动脉压(mPAP),图像分析法测量肺小动脉壁厚度,计算出管壁厚度占血管外径的百分比(WT%)和管壁面积占血管总面积的百分比(WA%),逆转录-聚合酶链式反应(RT-PCR)法观察大鼠肺组织fractalkine mRNA的表达和酶联免疫法观察肺组织匀浆fractalkine的变化。结果对照组大鼠mPAP为(16.3±2.1)mmHg(1 mmHg=0.133 kPa),低氧组为(28.7±3.8)mmHg,两组比较差异具有统计学意义(P<0.01);对照组大鼠WT%为(10.20±1.56)%、WA%为(38.11±2.30)%,低氧组大鼠WA%和WT%分别为(21.28±4.60)%和(67.08±9.44)%,两组比较差异均具有统计学意义(P均<0.01);低氧组大鼠肺组织fractalkine mRNA的含量较对照组增加〔(0.49±0.05)vs(0.29±0.02),P<0.01〕,肺组织匀浆fractalkine浓度亦高于对照组〔(7622.6±938.4)pg/mL vs(4168.5±403.5)pg/mL,P<0.01〕。相关分析表明,fractalkine mRNA和蛋白与WA%和WT%均呈正相关(P<0.05)。结论慢性低氧大鼠肺组织fractalkine的合成和释放增多,fractalkine增加可能与低氧性肺动脉高压的发生有关。

低氧大鼠血清和肺小动脉Fractalkine的变化

目的观察低氧性肺动脉高压形成过程中大鼠血清和肺小动脉fractalkine的表达变化,探讨fr-actalkine在低氧性肺动脉高压发病中的作用。方法通过间断低氧复制大鼠肺动脉高压模型,右心导管插入法检测平均肺动脉压力(mPAP),图像分析法测量肺小动脉厚度,酶联免疫法检测血清可溶性fractalkine的浓度,免疫组化及原位杂交法观察肺小动脉fractalkine蛋白和mRNA的表达。结果低氧14 d后的大鼠mPAP高于正常大鼠(P<0.01),但是,在低氧21 d时,肺小动脉厚度指标(WA%和WT%)及右心室肥厚指数RV/(LV+S)才增加(P<0.01)。与正常对照组比较,低氧21 d的大鼠肺小动脉fractalkine mRNA和蛋白表达明显增加,血清可溶性fractalkine浓度亦明显升高。相关分析显示fractalkine mRNA与WA%(r=0.749,P<0.01)和WT%(r=0.732,P<0.01)呈正相关,fractalkine蛋白与WA%(r=0.727,P<0.01)and WT%(r=0.683,P<0.01)亦呈正相关。结论慢性低氧刺激了fractalkine的合成和释放,fractalkine对于调节低氧性肺血管重建具有一定作用。

fractalkine在持续低氧大鼠肺动脉重构氧化应激机制中的作用

目的探讨fractalkine在持续低氧(CH)大鼠肺动脉重构氧化应激机制中的作用。方法 SD雄性大鼠18只按随机数字表法分为CH1、CH2和UC 3组。CH组舱内氧浓度保持10%～12%,7 h/d。CH1组给予NAC,CH2组予等量生理盐水。结果 CH1组血清及肺组织fractalkine、ROS、抑制羟自由基能力与CH2组及UC组比较差异有统计学意义(P<0.05);fractalkine与ROS正相关,与抑制羟自由基能力负相关。肺小动脉管壁厚度、WT%、WA%在CH1组较CH2组降低(P<0.05),较UC组升高(P<0.05)。三者与肺组织fractalkine、ROS成正相关,与抑制羟自由基能力呈负相关。结论 fractalkine参与CH大鼠肺动脉重构的发生,fractalkine可能是氧化应激导致肺小动脉重构的机制之一。

CircRNA-Tbpl1海绵吸附miR-214-3p调控自噬在低氧性肺动脉高压血管重塑中的作用及其机制

目的 探讨CircRNA-Tbpl1通过海绵吸附miR-214-3p调控自噬在低氧性肺动脉高压(HPH)血管重塑中的作用,并分析其机制。方法 12只8周龄C57BL/6雄性小鼠根据随机数字表法分为两组:对照组和HPH组,每组6只,通过低氧构建HPH模型小鼠,观察两组小鼠血流动力学差异,HE染色检测肺组织病理学改变,蛋白免疫印迹(Western blot)检测选择性自噬接头蛋白(p62)、微管相关蛋白1轻链3(LC3)和重组人自噬效应蛋白(Beclin-1)水平,实时荧光定量PCR(qRT-PCR)检测CircRNA-Tbpl1和miR-214-3p表达水平。分离小鼠原代肺动脉平滑肌细胞(PASMCs)并进行高、低氧分组培养,低氧处理PASMCs,细胞计数试剂盒-8(CCK-8)检测细胞活性,Western blot检测自噬相关蛋白表达,qRT-PCR检测CircRNA-Tbpl1的相对表达水平。通过转染和自噬诱导剂雷帕霉素干预,分析CircRNA-Tbpl1与PASMCs自噬的相关性。通过共转染shCircRNA-Tbpl1和miR-214-3p抑制物,分析CircRNA-Tbpl1/miR-214-3p对低氧诱导的PASMCs自噬和细胞增殖活性的影响。结果 与对照组小鼠比较,HPH组小鼠的右心室收缩压(RVSP)[(39.50±3.69)mmHg比(21.00±3.42)mmHg,P<0.01]、右心室肥厚指数(RVHI)[(0.43±0.05)比(0.24±0.03),P<0.01]显著增加,且HPH组小鼠肺血管出现明显的中膜肥大和外膜增生,肺血管重塑。同时,HPH组小鼠的肺组织中LC3Ⅱ、Beclin-1表达水平显著上调,p62表达下调,CircRNA-Tbpl1水平[(2.99±0.28)比(1.00±0.15),P<0.01]升高,miR-214-3p水平[(0.49±0.28)比(1.00±0.11),P<0.01]降低。与高氧组比较,低氧组PASMCs细胞增殖活力[(152.02±7.81)%比(100.00±2.08)%,P<0.05]增加,LC3Ⅱ和Beclin-1表达水平上调,p62表达下调,CircRNA-Tbpl1水平[(2.84±0.34)比(1.00±0.12),P<0.01]升高,而miR-214-3P水平[(0.52±0.07)比(1.00±0.15),P<0.01]降低。此外还发现,下调CircRNA-Tbpl1可抑制低氧诱导的PASMCs自噬,减弱细胞增殖活性[(70.23±7.30)%比(100.00±4.56)%,P<0.05]。双荧光素酶报告基因检测结果显示,CircRNA-Tbpl1海绵吸附miR-214-3p。与sh-NC组比较,sh-CircRNA-Tbpl1组的自噬水平减弱,细胞增殖活力降低[(71.13±8.17)%比(100.00±5.32)%,P<0.05]。与sh-CircRNA-Tbpl1+miRNA-NC组比较,sh-CircRNA-Tbpl1+miR-214-3p抑制物组的自噬水平升高,细胞增殖活力增强[(85.78±5.37)%比(69.80±6.34)%,P<0.05]。结论CircRNA-Tbpl1可能通过海绵吸附miR-214-3p抑制低氧诱导的自噬,从而缓解HPH血管重塑。

基于络病理论探讨靶向肺血管重塑治疗肺动脉高压

肺动脉高压(PH)是一种进行性的肺血管疾病,可导致右心衰竭及死亡。近年来,PH发病率逐年上升且缺乏有效治疗手段。中医辨治PH疗效显著,可发挥重要的协同作用。肺血管重塑是PH的核心病理特征,其与络脉的生理结构及病理变化关系密切。本文基于络病理论阐述PH中西医关键病机肺心脉络病变、肺血管重塑,分析PH中“脉络-血管”的生理,梳理其病理相关性,探讨中医靶向肺血管重塑辨治PH,从而为PH的临床治疗提供新思路。