Role of HIF-1α in hypercoagulable state of COPD in rats

Abstract

Objective: To explore the role of HIF-1α in hypercoagulable state of COPD induced by lipopolysaccharide plus smoking in rats. It also has to explore the regulatory mechanism of HIF-1α-EPO/EDN-1/VEGF pathway by using its activator and inhibitor.

Methods: 60 Sprague-Dawley rats (SD rats) were randomly divided into healthy control group, COPD hypercoagulable control group, activator group, and inhibitor group with 15 rats in each group. The healthy control group was fed freely. The other groups were given smoke and lipopolysaccharide by tracheal instillation to establish the experimental animal model of COPD hypercoagulability. After successful modeling, each experimental group was given 0.9 % sodium chloride solution and corresponding drugs by intraperitoneal injection for 7 days. Lung function was detected after drug administration. Hematoxylin-eosin staining was used to observe the pathological changes of lung tissue. Enzyme-linked immunosorbent assay was used to detect serum D-D,F (1 + 2),IL-6,TNF-α. The mRNA expressions of HIF-1α, EPO, EDN-1, and VEGF were detected by RT-PCR. Western-Blot and IHC were used to detect the expression of HIF-1α, EPO, EDN-1, and VEGF in lung tissue of rats.

Results: Compared with the healthy control group, rats in COPD hypercoagulable control group had COPD symptoms/signs, decreased lung function, increased the expression of serum D-D and F (1 + 2), increased the expression of inflammatory factors IL-6,TNF-α, and increased the expression of proteins HIF-1α, EPO, EDN-1 and VEGF. Compared with COPD hypercoagulable control group, lung function in activator group and inhibitor group had no obvious changes. The expressions of serum D-D,F (1 + 2),IL-6,TNF-α in activator group have increased noticeably. The expressions of proteins HIF-1α, EPO, EDN-1, and VEGF have further increased. Compared with COPD hypercoagulable control group, the expression of serum D-D, F (1 + 2), HIF-1α, EPO, EDN-1, and VEGF in the inhibitor group decreased.

Conclusion: HIF-1α-EPO/EDN-1/VEGF pathway plays an important role in the hypercoagulable state of COPD. HIF-1α inhibitor can improve airway inflammation and reduce hypercoagulability in COPD model rats.

Keywords: Blood hypercoagulability; Chronic obstructive pulmonary disease; HIF-1α; Hypercoagulable state.