OBJECTIVE: To investigate the effects of apple polyphenols on pulmonary vascular remodeling in rats with pulmonary arterial hypertension and its mechanism. METHODS: Rats were randomly divided into 4 groups:control (Con) group, monocrotaline (MCT) group, apple polyphenol (APP) group,monocrotaline + apple polyphenol (MCT+APP) group. In Con group, rats received a subcutaneous injection of physical saline. In APP group, rats received intraperitoneal injection of 20 mg/kg APP, every other day. In MCT group, rats received a single subcutaneous injection of MCT(60 mg/kg). In MCT+APP group, rats received subcutaneous injection of 60 mg/kg MCT followed by an intraperitoneal injection of 20 mg/kg APP every other day. All the disposal lasted 3 weeks. Then the PAH-relevant indicators, such as mean pulmonary artery pressure(mPAP), pulmonary vascular resistance(PVR), right ventricular hypertrophy index (RVHI) ,wall thickness (WT%) and wall area (WA%) were tested. After that, the inflammatory pathway related indicators, such as interleukin1(IL-1),interleukin1(IL-6), tumor necrosis factor α(TNF-α), cyclooxygenase 2(COX-2) and myeloperoxidase(MPO) in pulmonary tissue and free intracellular Ca in pulmonary smooth muscle cell(PASMC), content of eNOS and NO in endothelial cells were determined. RESULTS: Compared with the control group, the levels of mPAP, PVR, RVHI, WA%, WT%, and IL-1, IL-6, TNF-α, COX-2, MPO in tissue and the expression of Ca in PASMC of MCT group were increased significantly, while the contents of eNOS and NO in endothelial cells were decreased significantly (P＜0.05). Compared with the MCT group, the apple polyphenol treatment could improve the above mentioned situation, and the COX-2 and Ca indicators of the apple polyphenol treatment group were decreased significantly (P＜0.05). CONCLUSION MCT can increase COX-2 expression and intracellular Ca in pulmonary artery smooth muscle cells, decrease the contents of eNOS and NO in endothelial cells, while apple polyphenols can significantly inhibit these effects.
Animals ; Calcium ; metabolism ; Cyclooxygenase 2 ; metabolism ; Cytokines ; metabolism ; Malus ; chemistry ; Monocrotaline ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Polyphenols ; pharmacology ; Pulmonary Artery ; drug effects ; pathology ; Random Allocation ; Rats ; Vascular Remodeling ; drug effects

To investigate the effects and the underlying molecular mechanisms of curcumin on pulmonary artery smooth muscle cells in rat model with chronic obstructive pulmonary disease (COPD).A total of 75 male Wistar rats were randomly divided into control group (group CN), model group (group M), low-dose curcumin group (group CL), medium-dose curcumin group (group CM) and high-dose curcumin group (group CH). HE staining was used to observe the morphology of pulmonary artery. Proliferating cell nuclear antigen (PCNA), apoptosis-related protein Bcl-2 and Bax were detected by immunohistochemical staining. TUNEL kit was used to analyze the effects of curcumin on apoptosis of smooth muscle cells, and the protein expressions of SOCS-3/JAK2/STAT pathway in lung tissues were determined by western blot.Right ventricular systolic pressure (RVSP) and right ventricular hypertrophy index (RVMI) in group M were significantly higher than those in group CN, group CH and group CM (all<0.05). HE staining and TUNEL kit test showed that the number of pulmonary artery smooth muscle cells had a significant increase in group M, while the pulmonary artery tube became thin, and the smooth muscle cells shrinked in group CM and group CH. Immunohistochemistry showed that PCNA and Bcl-2 in group M were significantly higher than those in group CN (all<0.05), while Bax expression was significantly lower than that in group CN (<0.05). PCNA in group CM and group CH were significantly lower than that in group M (all<0.05), while Bax expression was significantly higher than that in group M (<0.05). Western blot showed that SOCS-3 protein was significantly decreased in group M, while the p-JAK2, p-STAT1, p-STAT3 were significantly increased (all<0.05). Compared with group M, SOCS-3 protein in group CM and group CH were significantly increased (all<0.05), while the p-JAK2, p-STAT3 were significantly reduced (all<0.05).Curcumin could promote the apoptosis of smooth muscle cells in rats with COPD, and improve the mean pulmonary artery pressure and RVMI through stimulating SOCS-3/JAK2/STAT signaling pathway.
Animals ; Apoptosis ; drug effects ; physiology ; Arterial Pressure ; drug effects ; physiology ; Curcumin ; pharmacology ; Hypertrophy, Right Ventricular ; pathology ; physiopathology ; Janus Kinase 2 ; drug effects ; physiology ; Lung ; chemistry ; drug effects ; Male ; Myocytes, Smooth Muscle ; drug effects ; pathology ; Proliferating Cell Nuclear Antigen ; drug effects ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; drug effects ; metabolism ; Pulmonary Artery ; drug effects ; pathology ; Pulmonary Disease, Chronic Obstructive ; pathology ; physiopathology ; Rats ; Rats, Wistar ; STAT Transcription Factors ; Suppressor of Cytokine Signaling 3 Protein ; drug effects ; physiology ; Ventricular Pressure ; drug effects ; bcl-2-Associated X Protein ; drug effects ; metabolism

To discuss the effect of puerarin (Pue) on the proliferation of hypoxia-induced pulmonary artery smooth muscle cells (PASMCs) and discuss whether its mechanism is achieved by regulating reactive oxygen. PASMCs of primarily cultured rats (2-5 generations) were selected in the experiment. MTT, Western blot, FCM and DCFH-DA were used to observe Pue's effect the proliferation of PASMCs. The Western blot was adopted to detect whether ROS participated in Pue's effect in inhibiting PASMC proliferation. The PASMCs were divided into five groups: the normoxia group, the hypoxia group, the hypoxia + Pue group, the hypoxia + Pue + Rotenone group and the hypoxia + Rotenone group, with Rotenone as the ROS blocker. According to the results, under the conditions of normoxia, Pue had no effect on the PASMC proliferation; But, under the conditions of hypoxia, it could inhibit the PASMC proliferation; Under the conditions of normoxia and hypoxia, Pue had no effect on the expression of the tumor necrosis factor-α (TNF-α) among PASMCs, could down-regulate the expression of hypoxia-induced cell cycle protein Cyclin A and proliferative nuclear antigen (PCNA). DCFH-DA proved Pue could reverse ROS rise caused by hypoxia. Both Rotenone and Pue could inhibit the up-regulated expressions of HIF-1α, Cyclin A, PCNA caused by anoxia, with a synergistic effect. The results suggested that Pue could inhibit the hypoxia-induced PASMC proliferation. Its mechanism may be achieved by regulating ROS.
Animals ; Cell Cycle ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Hypoxia ; pathology ; Isoflavones ; pharmacology ; Male ; Myocytes, Smooth Muscle ; drug effects ; physiology ; Proliferating Cell Nuclear Antigen ; analysis ; Pulmonary Artery ; cytology ; drug effects ; Rats ; Rats, Wistar ; Reactive Oxygen Species ; metabolism

OBJECTIVETo investigate the effect of panax notoginseng saponins (PNS) injection on pulmonary artery pressure and the expression of p38MAPK in lung tissue of rats subjected to chronic hypoxia.

METHODSThirty adult male Sprague Dawley rats were randomly divided into three groups (ten in each group): rats in control group were exposed to normoxic condition and the rats in hypoxia group and PNS group were subjected to 4-week hypoxia, and PNS injection (50 mg · kg(-1) · d(-1)) was administrated intraperitoneally at 30 min in the PNS group daily before the rats were kept in the hypoxic chamber, while rats in the other two groups received equal dose of normal saline instead. After chronic hypoxia, mean pulmonary artery pressure (mPAP) and mean carotid artery pressure (mCAP) were measured. The heart and lung tissues were harvested, and right ventricle (RV) and left ventricle plus ventricular septum (LV+S) were weighed to calculate the ratio of RV/(LV+S). The expression of p38MAPK mRNA was determined by reverse transcription-polymerase chain reaction, the quantity of phosphorylated p38MAPK (p-p38MAPK) in rat lung tissues and pulmonary arterioles was determined by Western blot and immunohistochemistry.

RESULTSCompared with the control group, mPAP and the ratio of RV/(LV+S) in the hypoxia group were increased, the expression of p-p38MAPK in pulmonary arterioles and p38MAPK mRNA in the lung were higher (P<0.05). The changes of these parameters in the hypoxia group were significantly attenuated by PNS treatment (P<0.05).

CONCLUSIONPNS injection was shown to prevent hypoxic pulmonary hypertension at least partly by regulating p38MAPK pathway.

Animals ; Arterioles ; drug effects ; metabolism ; Blood Pressure ; drug effects ; Blotting, Western ; Carotid Arteries ; drug effects ; physiopathology ; Disease Models, Animal ; Heart Ventricles ; drug effects ; physiopathology ; Hemodynamics ; drug effects ; Hypertension, Pulmonary ; complications ; enzymology ; physiopathology ; Hypoxia ; complications ; enzymology ; physiopathology ; Injections ; Lung ; drug effects ; enzymology ; pathology ; physiopathology ; MAP Kinase Signaling System ; drug effects ; Male ; Panax notoginseng ; chemistry ; Pulmonary Artery ; drug effects ; physiopathology ; RNA, Messenger ; genetics ; metabolism ; Rats, Sprague-Dawley ; Saponins ; administration & dosage ; pharmacology ; p38 Mitogen-Activated Protein Kinases ; genetics ; metabolism

Pulmonary arterial hypertension (PAH) causes right ventricular failure due to a gradual increase in pulmonary vascular resistance. The purposes of this study were to confirm the engraftment of human umbilical cord blood-mesenchymal stem cells (hUCB-MSCs) placed in the correct place in the lung and research on changes of hemodynamics, pulmonary pathology, immunomodulation and several gene expressions in monocrotaline (MCT)-induced PAH rat models after hUCB-MSCs transfusion. The rats were grouped as follows: the control (C) group; the M group (MCT 60 mg/kg); the U group (hUCB-MSCs transfusion). They received transfusions via the external jugular vein a week after MCT injection. The mean right ventricular pressure (RVP) was significantly reduced in the U group after the 2 week. The indicators of RV hypertrophy were significantly reduced in the U group at week 4. Reduced medial wall thickness in the pulmonary arteriole was noted in the U group at week 4. Reduced number of intra-acinar muscular pulmonary arteries was observed in the U group after 2 week. Protein expressions such as endothelin (ET)-1, endothelin receptor A (ERA), endothelial nitric oxide synthase (eNOS) and matrix metalloproteinase (MMP)-2 significantly decreased at week 4. The decreased levels of ERA, eNOS and MMP-2 immunoreactivity were noted by immnohistochemical staining. After hUCB-MSCs were administered, there were the improvement of RVH and mean RVP. Reductions in several protein expressions and immunomodulation were also detected. It is suggested that hUCB-MSCs may be a promising therapeutic option for PAH.
Animals ; Cytokines/metabolism ; Disease Models, Animal ; Endothelin-1/metabolism ; Fetal Blood/*cytology ; Gene Expression Regulation/drug effects ; Hemodynamics ; Humans ; Hypertension, Pulmonary/chemically induced/*therapy ; Hypertrophy, Right Ventricular/physiopathology ; Immunohistochemistry ; Lung/metabolism/pathology ; Male ; Matrix Metalloproteinase 2/metabolism ; *Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells/*cytology/metabolism ; Monocrotaline/toxicity ; Nitric Oxide Synthase Type III/metabolism ; Pulmonary Artery/pathology ; Rats ; Rats, Sprague-Dawley ; Receptor, Endothelin A/metabolism

OBJECTIVETo investigate the mechanism of how curcumin improves pulmonary vascular remodeling associated with chronic pulmonary arterial hypertension.

METHODSThe model of chromic hypoxia hypercapniapulmoary remodeling was made. Twenty-four male rats were randomly divided into 4 groups (n = 6): group I (normoxia control group), group II (hypxia and hypercapnia model group), group II (disodium cromoglycate control group), group IV (curcumin treated group). The last 3 group rats were put in a hypoxia cabin where the concentrate of O2 was 8% - 11% and the concentrate of CO2 was 3% - 5%, for 8 h a day and lasting 4 w in total. Group III rats were intraperitoneally injected with disodium cromoglycate (20 mg/kg) and group IV rats were administrated with curcumin by gavage (150 mg/kg). The morphological changes of pulmonary vessel walls and the ultrastructure of mast cells were observed by the optics microscope and the transmission electron microscope. Mast cells and its degranulation state were measured by toluidine blue staining and immunohistochemistry. Data were expressed as means ± SD (standard deviation) and analyzed with SPSS17.0 software.

RESULTS(1) By optics microscopy observation, the value of WA/TA was significantly higher in II group than other groups (P < 0.05). (2) Electron microscope showed that the endothelial cells of pulmonary arterioles in III and IV group were near to I group and the proliferation of pulmonary arterial media smooth cell layer and collagen fibers in adventitia was much lighter than those in II group. The membrane of mast cells was more intact in I, III, IV group than II group. (3) The number of mast cells, the degranulation rate of master cells and the number of positive tryptase stained cells in II group were significantly more than those in other groups. (P < 0.05).

CONCLUSIONCurcumin may inhibit the remodeling of pulmonary vessel induced by chronic hypoxia hypercapnia by mast cell regulation.

Animals ; Cell Degranulation ; Curcumin ; pharmacology ; Hypercapnia ; physiopathology ; Hypertension, Pulmonary ; drug therapy ; Hypoxia ; physiopathology ; Lung ; pathology ; Male ; Mast Cells ; physiology ; ultrastructure ; Pulmonary Artery ; drug effects ; Rats ; Rats, Sprague-Dawley ; Vascular Remodeling ; drug effects

BACKGROUNDPulmonary embolism (PE) is a common and often fatal disease. Early after pulmonary thromboembolism, inflammation and associated intimal hyperplasia occur within the pulmonary arteries, similar to what is observed with chronic thromboembolic pulmonary hypertension. This study tested the hypothesis that thrombolytic and anticoagulant agents would have anti-inflammatory effects or inhibit intimal hyperplasia of involved pulmonary arteries.

METHODSSeventy-two male New Zealand white rabbits were randomly divided into two groups (54 rabbits in the PE group and 18 in the sham group). Experimental PE was induced in 54 rabbits by femoral vein injection of autologous blood clots and confirmed with pulmonary angiography, and other 18 rabbits underwent sham operations. Fifty-four rabbits in the PE group were randomly divided into three groups: a control group (treated with normal saline), a low-molecular- weight heparin (LMWH) group (treated with LMWH), and a urokinase (UK) group (treated with UK). Arterial blood gas was analyzed at 2, 7, and 28 days (n = 6 per time point by random group division), then lung tissues were removed and were analyzed for pro-inflammatory cytokines and chemokines, and were stained for intimal hyperplasia.

RESULTSThe overall survival of rabbits undergoing PE was 100%. PE distribution detected on digital signal angiography (DSA) and histopathology was shown in 67% of rabbits (36/54) in the bilateral low lobar pulmonary arteries (PAs). The results showed that alveolar-arterial partial pressure of oxygen (PO2) difference (PA-aO2) significantly increased and PO2 decreased in the control group compared with the sham group. Compared with controls, the UK group had a decreased level of PA-aO2 on day 2 (P < 0.05), however, there was no significant difference in the LMWH group. Compared with controls, the LMWH group had a decreased level of monocyte chemoattractant protein-1 (MCP-1) in affected tissue and serum samples on days 7 and 28 (P < 0.05), and the UK group had decreased levels on days 2 and 7 (P < 0.05). Compared with sham group, all PE groups had an increased level of interleukin-13 (IL-13) and transforming growth factor-β (TGF-β) in unaffected lung tissue samples at days 2 and 7. IL-13 in affected lung tissue in the LMWH group was decreased at all time points compared with controls (P < 0.05). However, TGF-β in affected lung tissue of the LMWH and UK groups increased at day 28. There was less intimal hyperplasia in involved pulmonary arteries at days 7 and 28 in the LMWH group compared with controls; there was no statistical difference in the UK group compared with controls.

CONCLUSIONSUK treatment can rapidly improve the V/Q mismatch in PE and appears a short-term anti-inflammatory benefit. However, LMWH maybe inhibit the later local inflammatory reaction and reduce intimal hyperplasia.

Animals ; Chemokines ; analysis ; Cytokines ; analysis ; Heparin, Low-Molecular-Weight ; therapeutic use ; Male ; Oxygen ; blood ; Pulmonary Artery ; drug effects ; pathology ; Pulmonary Embolism ; drug therapy ; immunology ; Rabbits ; Urokinase-Type Plasminogen Activator ; therapeutic use

The purpose of this study was to investigate the therapeutic effects of small hairpin RNA (shRNA) targeting endothelin-converting enzyme (ECE)-1 in monocrotaline (MCT)-induced pulmonary hypertensive rats. Ninty-four Sprague-Dawley rats were divided into three groups: control (n = 24), MCT (n = 35) and shRNA (n = 35). Four-week survival rate in the shRNA group was significantly increased compared to that in the MCT group. The shRNA group showed a significant improvement of right ventricular (RV) pressure compared with the MCT group. The MCT and shRNA groups also showed an increase in RV/(left ventricle + septum) ratio and lung/body weight. Plasma endothelin (ET)-1 concentrations in the shRNA group were lower than those in the MCT group. Medial wall thickness of pulmonary arterioles were increased after MCT injection and was significantly decreased in the shRNA group. The number of intra-acinar muscular pulmonary arteries was decreased in the shRNA group. The mRNA expressions of ET-1 and ET receptor A (ETA) were significantly decreased in the shRNA group in week 4. The protein levels of ETA were decreased in the shRNA group in week 2. The protein levels of tumor necrosis factor-alpha and vascular endothelial growth factor were decreased in the shRNA group in week 4. In conclusion, the gene silencing with lentiviral vector targeting ECE-1 could be effective against hemodynamic, histopathological and gene expression changes in pulmonary hypertension.
Animals ; Aspartic Acid Endopeptidases/*antagonists & inhibitors/blood/genetics ; Body Weight ; Heart Ventricles/physiopathology ; Hypertension, Pulmonary/chemically induced/*enzymology/mortality ; Lentivirus/genetics ; Lung/anatomy & histology/metabolism/pathology ; Male ; Metalloendopeptidases/*antagonists & inhibitors/blood/genetics ; Monocrotaline/toxicity ; Pulmonary Artery/drug effects/physiopathology ; RNA, Small Interfering/*metabolism ; Rats ; Rats, Sprague-Dawley ; Receptor, Endothelin A/genetics/metabolism ; Survival Rate ; Tumor Necrosis Factor-alpha/metabolism ; Vascular Endothelial Growth Factor A/metabolism

Intravenous and intratracheal implantation of mesenchymal stem cells (MSCs) may offer ameliorating effects on pulmonary hypertension (PH) induced by monocrotaline (MCT) in rats. The aim of this study was to examine the anti-remodeling effect of intravenous MSCs (VMSCs) and intratracheal MSCs (TMSCs) in rats with PH, and the underlying mechanisms. MSCs were isolated from rat bone marrow and cultured. PH was induced in rats by intraperitoneal injection of MCT. One week after MCT administration, the rats were divided into 3 groups in terms of different treatments: VMSCs group (intravenous injection of MSCs), TMSCs group (intratracheal injection of MSCs), PH group (no treatment given). Those receiving saline instead of MCT served as negative control (control group). Pulmonary arterial structure was pathologically observed, pulmonary arterial dynamics measured, and remodeling-associated cytokines Smad2 and Smad3 detected in the lungs, three weeks after MCT injection. The results showed that PH group versus control group had higher pulmonary arterial pressure (PAP) and wall thickness index (WTI) 21 days after MCT treatment. The expression of phosphorylated (p)-Smad2 and the ratio of p-Smad2/Smad2 were much higher in PH group than in control group. Fluorescence-labeled MSCs were extensively distributed in rats' lungs in VMSCs and TMSCs groups 3 and 14 days after transplantation, but not found in the media of the pulmonary artery. WTI and PAP were significantly lower in both VMSCs and TMSCs groups than in PH group three weeks after MCT injection. The p-Smad2 expression and the ratio of p-Smad2/Smad2 were obviously reduced in VMSCs and TMSCs groups as compared with those in PH group. In conclusion, both intravenous and intratracheal transplantation of MSCs can attenuate PAP and pulmonary artery remodeling in MCT-induced PH rats, which may be associated with the early suppression of Smad2 phosphorylation via paracrine pathways.
Animals ; Atrial Remodeling ; drug effects ; physiology ; Hypertension, Pulmonary ; chemically induced ; physiopathology ; Male ; Mesenchymal Stromal Cells ; pathology ; Monocrotaline ; pharmacology ; Pulmonary Artery ; drug effects ; physiopathology ; Rats ; Rats, Sprague-Dawley

OBJECTIVEIt is known that Notch signal is very important to vascular remodeling during the process of embryonic development, vessel repair and tumor growth, but there are few studies about pulmonary vascular remodeling in pulmonary hypertension. This study was to explore the effect of inhibiting Notch signal on pulmonary vascular remodeling induced by angiotensin II.

METHODSVessel strips taken from healthy Wistar rats were co-cultured with extrogenous angiotensin II and the potent smooth muscle cell proliferation stimulators for 7 days. Vascular wall thickness, proliferating cell nuclear antigen (PCNA) positive cell rate and caspase-3 positive cell rate were examined in vessel strips. Then some vessel strips were cultured with angiotensin II and γ-secretase inhibitor DAPT, a Notch signaling inhibitor for 7 days. The levels of Notch 1 to 4 receptor and HERP1/2 mRNA were ascertained by FQ-PCR.

RESULTSAngiotensin II stimulation in the cultured normal pulmonary arteries resulted in an increase in the vascular medial thickness by nearly 50%, and a significant increase in the PCNA positive cell rate and a decrease in the caspase-3 positive cell rate. DAPT treatment did not result in the alterations of Notch 1 to 4 receptor levels, but decreased remarkably HERP1 and HERP2 mRNA expression. DAPT treatment also decreased angiotensin II-induced vascular medial thickness and PCNA positive cell rate and increased caspase-3 positive cell rate.

CONCLUSIONSInhibiting Notch signal by γ-secretase inhibitor may lead to the suppression of pulmonary vascular remodeling induced by angiotensin II, suggesting that the inhibition of Notch signal pathway might be a novel strategy for the treatment of pulmonary hypertension.

Angiotensin II ; pharmacology ; Animals ; Dipeptides ; pharmacology ; Proliferating Cell Nuclear Antigen ; analysis ; Pulmonary Artery ; drug effects ; pathology ; Rats ; Rats, Wistar ; Receptors, Notch ; antagonists & inhibitors ; physiology ; Signal Transduction ; drug effects ; physiology