Abstract 532: New Agonist of A2a Receptor Reduces Ventricular and Vascular Dysfunction in Monocrotaline-induced Pulmonary Arterial Hypertension in Rats

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Allan K Alencar ◽  
Sharlene L Pereira ◽  
Arthur E Kummerle ◽  
Sharon S Langraf ◽  
Celso Caruso-Neves ◽  
...  

Pulmonary arterial hypertension (PAH) is characterized by enhanced pulmonary vascular resistance with subsequent remodeling and right ventricular hypertrophy. Vascular reactivity and ventricular function were investigated in rats with monocrotaline-induced PAH and treated with a new N-acylhydrazone derivative named as LASSBio-1359. METHODS: Protocols were approved by Animal Care and Use Committee at Universidade Federal do Rio de Janeiro. Male Wistar rats received a single i.p. injection of monocrotaline (MCT) (60 mg/kg) for PAH induction and were randomly divided in groups which were treated with: saline, vehicle and LASSBio-1359 (50 mg/kg p.o.). After 14 days of treatment, some parameters were evaluated: pulmonary acceleration time (PAT); right ventricular systolic pressure (RVSP); vascular reactivity to acetylcholine; expression of iNOS in pulmonary tissue; wall thickness of pulmonary artery (PAWT). Results: PAT (ms) was increased from 26.2 ± 2.8 to 41.3 ± 3.9 in PAH group treated with vehicle (n=8, p<0.05) and was reduced to 24.2 ± 1.7 when PAH group was treated with LASSBio-1359. RVSP (mmHg) increased from 26.0 ± 2.0 to 55.2 ± 2.3 in PAH group (p<0.05) but was similar to control after treatment with LASSBio-1359 (31.8 ± 2.3 mm Hg). Ratio of right ventricle and body weight (mg/g) was 0.66 ± 0.02, 1.63 ± 0.16 and 0.87 ± 0.10 for control, vehicle- and LASSBio-1359-treated PAH groups, respectively. PAH promoted ventricular dysfunction which was reduced by LASSBio-1359. The pulmonary artery maximum relaxation (%) was 57.3 ± 5.5, 43.6 ± 1.2 and 61.4 ± 8.4 for control, vehicle and LASSBio-1359-treated groups indicating that PAH promoted endothelium injury which was recovered by LASSBio-1359. iNOS expression in pulmonary tissue was increased from 0.48 ± 1.31 to 0.98 ± 3.14 in PAH group and reduced to 0.53 ± 1.83 in rats treated with LASSBio-1359. The PAWT (%) were increased from 74.1 ± 1.3 to 90.2 ± 2.7 in PAH group (p<0.05) but was 74.4 ± 1.3 when treated with LASSBio-1359. This compound showed an in vitro vasodilatory activity mediated by activation of adenosinergic A2A receptor. Conclusion: LASSBio-1359 reduced ventricular and vascular dysfunction in monocrotaline-induced PAH in rats indicating a possible new alternative to treat PAH.

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
E Oliver ◽  
S.F Rocha ◽  
M Spaczynska ◽  
D.V Lalama ◽  
M Gomez ◽  
...  

Abstract Background Endothelial dysfunction is one of the most important hallmarks of pulmonary arterial hypertension (PAH). This leads to anomalous production of vasoactive mediators that are responsible for a higher vascular tone and a subsequent increase in pulmonary artery pressure (PAP), and to an increased vascular permeability that favors perivascular inflammation and remodeling, thus worsening the disease. Therefore, preservation of the endothelial barrier could become a relevant therapeutic strategy. Purpose In previous studies, others and we have suggested the pharmacological activation of the β3-adrenergic receptor (AR) as a potential therapeutic strategy for pulmonary hypertension (PH) due to left heart disease. However, its potential use in other forms of PH remain unclear. The aim of the present study was to elucidate whether the β3-AR agonist mirabegron could preserve pulmonary endothelium function and be a potential new therapy in PAH. Methods For this purpose, we have evaluated the effect of mirabegron (2 and 10 mg/kg·day) in different animal models, including the monocrotaline and the hypoxia-induced PAH models in rats and mice, respectively. Additionally, we have used a transgenic mouse model with endothelial overexpression of human β3-AR in a knockout background, and performed in vitro experiments with human pulmonary artery endothelial cells (HPAECs) for mechanistic experiments. Results Our results show a dose dependent effect of mirabegron in reducing mean PAP and Right Ventricular Systolic Pressure in both mice and rats. In addition, the use of transgenic mice has allowed us to determine that pulmonary endothelial cells are key mediators of the beneficial role of β3-AR pathway in ameliorating PAH. Mechanistically, we have shown in vitro that activation of β3-AR with mirabegron protects HPAECs from hypoxia-induced ROS production and mitochondrial fragmentation by restoring mitochondrial fission/fusion dynamics. Conclusions This protective effect of mirabegron would lead to endothelium integrity and preserved pulmonary endothelial function, which are necessary for a correct vasodilation, avoiding increased permeability and remodeling. Altogether, the current study demonstrates a beneficial effect of the β3-AR agonist mirabegron that could open new therapeutic avenues in PAH. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Programa de Atracciόn de Talento, Comunidad de Madrid


Pulmonology ◽  
2019 ◽  
Vol 25 (4) ◽  
pp. 248-251
Author(s):  
S. Hoette ◽  
N. Creuzé ◽  
C.E. Rochitte ◽  
G. Simonneau ◽  
M. Humbert ◽  
...  

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Yijia Xiang ◽  
Changhong Cai ◽  
Yonghui Wu ◽  
Lebing Yang ◽  
Shiyong Ye ◽  
...  

Background. Pulmonary artery remodeling is important in the development of pulmonary artery hypertension. The TGF-β1/Smads signaling pathway is activated in pulmonary arterial hypertension (PAH) in rats. Icariin (ICA) suppresses the TGF-β1/Smad2 pathway in myocardial fibrosis in rats. Therefore, we investigated the role of icariin in PAH by inhibiting the TGF-β1/Smads pathway. Methods. Rats were randomly divided into control, monocrotaline (MCT), MCT + ICA-low, and MCT + ICA-high groups. MCT (60 mg/kg) was subcutaneously injected to induce PAH, and icariin (50 or 100 mg/kg.d) was orally administered for 2 weeks. At the end of the fourth week, right ventricular systolic pressure (RVSP) was obtained and the right ventricular hypertrophy index (RI) was determined as the ratio of the right ventricular weight to the left ventricular plus septal weight (RV/LV + S). Western blots were used to determine the expression of TGF-β1, Smad2/3, P-Smad2/3, and matrix metalloproteinase-2 (MMP2) in lung tissues. Results. Compared to the control group, RVSP and RI were increased in the MCT group (ρ < 0.05). Additionally, TGF-β1, Smad2/3, P-Smad2/3, and MMP2 expressions were obviously increased (ρ < 0.01). Compared to the MCT group, RVSP and RI were decreased in the MCT + ICA group (ρ < 0.05). TGF-β1, Smad2/3, P-Smad2/3, and MMP2 expressions were also inhibited in the icariin treatment groups (ρ < 0.05). Conclusions. Icariin may suppress MCT-induced PAH via the inhibition of the TGFβ1-Smad2/3 pathway.


2019 ◽  
Vol 9 (4) ◽  
pp. 204589401987859 ◽  
Author(s):  
Guosen Yan ◽  
Jinxia Wang ◽  
Tao Yi ◽  
Junfen Cheng ◽  
Haixu Guo ◽  
...  

Pulmonary arterial hypertension is a rapidly progressive and often fatal disease. As the pathogenesis of pulmonary arterial hypertension remains unclear, there is currently no good drug for pulmonary arterial hypertension and new therapy is desperately needed. This study investigated the effects and mechanism of baicalin on vascular remodeling in rats with pulmonary arterial hypertension. A rat pulmonary arterial hypertension model was constructed using intraperitoneal injection of monocrotaline, and different doses of baicalin were used to treat these rats. The mean pulmonary arterial pressure (mPAP) and right ventricular systolic pressure (RVSP) were measured with a right heart catheter. Moreover, the hearts were dissected to determine the right ventricular hypertrophy index (RVHI). The lung tissues were stained with H&E and Masson's staining to estimate the pulmonary vascular remodeling and collagen fibrosis, and the expression of proteins in the AKT, ERK, and NF-κB p65 phosphorylation (p-AKT, p-ERK, p-p65) was examined by Western blot analysis. We found that compared with untreated pulmonary arterial hypertension rats, baicalin ameliorated pulmonary vascular remodeling and cardiorespiratory injury, inhibited p-p65 and p-ERK expression, and promoted p-AKT and p-eNOS expression. In conclusion, baicalin interfered with pulmonary vascular remodeling and pulmonary arterial hypertension development in rats through the AKT/eNOS, ERK and NF-κB signaling pathways.


2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Gisele Zapata-Sudo ◽  
Allan K Alencar ◽  
Sharlene L Pereira ◽  
Emanelle Ferraz ◽  
José H Nascimento ◽  
...  

Aims: Pulmonary arterial hypertension (PAH) consists of increased pulmonary vascular resistance and remodeling and right ventricular hypertrophy. This work investigated the effects of a new N -acylhydrazone derivative, (E)-N’-(3,4-dimethoxybenzylidene)-4-methoxybenzohydrazide (LASSBio-1386), in rats with monocrotaline (MCT)-induced PAH. Methods and Results: Protocols were approved by Animal Care and Use Committee at Universidade Federal do Rio de Janeiro. Male Wistar rats received a single i.p. injection of MCT (60 mg/kg) for PAH induction. Experimental groups were: control, MCT + vehicle (DMSO), MCT + LASSBio-1386 (50 mg/kg p.o.). The animals were treated with vehicle or LASSBio-1386 for 14 days after the onset of disease (n = 6). Right ventricular systolic pressure (RVSP) and relation between RV weight to body weight (RV/BW) were analyzed. Transthoracic echocardiography was performed to determine pulmonary acceleration time (PAT), pulmonary artery diameter and RV wall thickness. Pulmonary vascular morphometry was analyzed using images of terminal arterioles and wall thickness was measured. The parameters evaluated are shown in table 1. In addition, LASSBio-1386-induced vasorelaxation was mediated partially by the activation of A2A adenosine receptors, with an IC50 of 6.2 ± 1.2 µM. Docking analysis in the A 2A crystal structure was performed using the program GOLD 5.1 and showed the interaction of the compound with A 2A receptor. Conclusions: LASSBio-1386 effectively reversed right ventricular hypertrophy and pulmonary vascular remodeling in rats with MCT-induced PAH through activation of adenosine receptor.


2017 ◽  
Vol 45 (04) ◽  
pp. 773-789 ◽  
Author(s):  
Lin-Bo Yuan ◽  
Chun-Yan Hua ◽  
Sheng Gao ◽  
Ya-Ling Yin ◽  
Mao Dai ◽  
...  

Astragalus polysaccharides (APS) have been shown to possess a variety of biological activities including anti-oxidant and anti-inflammation functions in a number of diseases. However, their function in pulmonary arterial hypertension (PAH) is still unknown. Rats received APS (200[Formula: see text]mg/kg once two days) for 2 weeks after being injected with monocrotaline (MCT; 60[Formula: see text]mg/kg). The pulmonary hemodynamic index, right ventricular hypertrophy, and lung morphological features of the rat models were examined, as well as the NO/eNOS ratio of wet lung and dry lung weight and MPO. A qRT-PCR and p-I[Formula: see text]B was used to assess IL-1[Formula: see text], IL-6 and TNF-[Formula: see text] and WB was used to detect the total I[Formula: see text]B. Based on these measurements, it was found that APS reversed the MCT-induced increase in mean pulmonary arterial pressure (mPAP) (from 32.731[Formula: see text]mmHg to 26.707[Formula: see text]mmHg), decreased pulmonary vascular resistance (PVR) (from 289.021[Formula: see text]mmHg[Formula: see text][Formula: see text] min/L to 246.351[Formula: see text]mmHg[Formula: see text][Formula: see text][Formula: see text]min/L), and reduced right ventricular hypertrophy (from 289.021[Formula: see text]mmHg[Formula: see text][Formula: see text][Formula: see text]min/L to 246.351 mmHg[Formula: see text][Formula: see text][Formula: see text]min/L) ([Formula: see text]0.05). In terms of pulmonary artery remodeling, the WT% and WA% decreased with the addition of APS. In addition, it was found that APS promoted the synthesis of eNOS and the secretion of NO, promoting vasodilation and APS decreased the MCT-induced elevation of MPO, IL-1[Formula: see text], IL-6 and TNF-[Formula: see text], reducing inflammation. Furthermore, APS was able to inhibit the activation of pho-I[Formula: see text]B[Formula: see text]. In couclusion, APS ameliorates MCT-induced pulmonary artery hypertension by inhibiting pulmonary arterial remodeling partially via eNOS/NO and NF-[Formula: see text]B signaling pathways.


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