[Early treatment with hepatocyte growth factor improves pulmonary artery and right ventricular remodeling in rats with pulmonary artery hypertension by modulating cytokines expression]

Abstract

Objective: To investigate the effect of early treatment with hepatocyte growth factor (HGF) on the cytokine expression and pulmonary artery, right ventricular (RV) remodeling in the rat model of pulmonary artery hypertension (PAH).

Methods: The rat model of PAH was produced by injecting monocrotaline, and the model rats were randomly divided into empty adenovirus transfection group (MCT group, n = 10) and HGF gene transfection group(HGF group, n = 10). Another group of rats served as the Sham operation group (Sham group n = 10). After 4 weeks of HGF gene transfection, the histological sections of the lungs and right ventricular (RV) were stained with hematoxylin-eosin (HE) and the pulmonary artery and RV remodeling were examined. The rat lung sections were also immunostained with antibodies against factor VIII, and the capillary density were calculated. Meanwhile, the mRNA expression of TNF-α, IL-6, IL-1β and TGF-β1 in pulmonary arteries and RV were detected by RT-PCR.

Results: HGF gene treatment significantly decreased the ratio of vessel wall thickness to pulmonary artery diameter and the ratio of vessel wall area to total area, and increased the capillary density of lung in PAH rats. HGF gene treatment also significantly decreased cross-sectional area of cardiomyocytes and collagen deposited in RV. Moreover, HGF gene treatment significantly decreased the expression of cytokines in pulmonary artery (TNF-α: 0.82 ± 0.07 vs 0.49 ± 0.09, IL-6: 1.13 ± 0.19 vs 0.68 ± 0.09, IL-1β: 0.86 ± 0.11 vs 0.51 ± 0.07, TGF-β1: 1.18 ± 0.12 vs 0.59 ± 0.10) and RV (TNF-α: 0.79 ± 0.11 vs 0.48 ± 0.08, IL-6: 1.03 ± 0.11 vs 0.63 ± 0.09, IL-1β: 0.81 ± 0.11 vs 0.52 ± 0.07, TGF-β1: 0.94 ± 0.12 vs 0.53 ± 0.10) in MCT induced PAH rats (P < 0.05) .

Conclusion: Early treatment with HGF improves pulmonary artery and RV remodeling, possibly by decreasing the expression of TNF-α, IL-6, IL-1β and TGF-β1 in pulmonary arteries and RV.