Abstract P1133: Association Of Mesenchymal Stem Cells Therapy And An Agonist Of Adenosine Receptor On Monocrotaline-induced Pulmonary Arterial Hypertension In Rats

Abstract

Introduction: Pulmonary arterial hypertension (PAH) is characterized by an intense inflammatory component leading to vascular remodeling, increasing the pulmonary artery pressure, eventually resulting in right ventricular dysfunction. Hypothesis: Association of human mesenchymal stem cells (hMSC) therapy and LASSBio-1860 (agonist of adenosine receptors) would reduce the inflammatory response and vascular remodeling, decreasing the vascular resistance and pulmonary artery pressure, improving right ventricle function and reducing hypertrophy. Methods: Protocols were approved by Animal Care and Use Committee at Universidade Federal do Rio de Janeiro. PAH was induced in male Wistar rats by injection of monocrotaline (MCT; 60 mg/kg, i.p.) and confirmed within 14 days by transthoracic echocardiography. Groups were orally treated daily during 14 days with vehicle, LASSBio-1860 (180 μmol/kg) after a single intravenous injection of 10 5 hMSC At the end of protocol, tissues were collected and processed to evaluate expression of proteins using immunohistochemical and western-blotting analysis. Results: Mean pulmonary artery acceleration time (PAAT) was reduced in MCT-induced PAH group compared to the control group from 31.0 ± 1.5 to 21.9 ± 1.3 ms. In contrast, the association of LASSBio-1860 and hMSC has recovered the PAAT to 31.0 ± 2.0 ms, which effect was not observed in isolated treatment either with LASSBio-1860 or hMSC (23.5 ± 2.1 and 22.2 ± 2.2 ms). Table 1 shows hemodynamic, molecular and immunohistochemical parameters. In conclusion, the association of LASSBio-1860 and hMSC improved hemodynamic, morphologic and inflammatory parameters in an MCT-induced model of PAH.