Abstract:

Objective To investigate expressions of adiponectin receptors (AdipoR1, AdipoR2) in lung tissue in type 1 and type 2 diabetes mellitus rats induced by streptozotocin (STZ). Methods A total of 40 SD rats were randomly divided into 4 groups: control (Con) group, type 1 diabetes mellitus (1-DM) group, 72 h after STZ injection (72 h) group, and type 2 diabetes mellitus (2-DM) group. The rats in 1-DM group and 72 h group were injected STZ intraperitoneally with a dose of 60 mg/kg while the ones in Con group were only done with the same dose of citric acid buffer. The rats in 2-DM group were injected STZ intraperitoneally with a dose of 35 mg/kg. Serum insulin and adiponectin levels were evaluated by ELISA. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) in lung tissue were measured. Expression of AdipoR1, AdipoR2 in lung tissue was determined by immunohistochemistry. The pathological changes of lung tissue were examined by HE staining under light microscope. Results The levels of serum adiponectin in 1-DM and 2-DM groups were lower than that in Con group (P<0.05). The level of serum adiponectin in 2-DM group was lower than that of 1-DM group (P<0.05). Compared with Con group, the expression of AdipoR1 and activity of SOD in lung tissue in 1-DM and 2-DM groups were lower while those in 72 h group were similar. In 1-DM and 2-DM groups, the rat lung tissue manifested injuries such as basement membrane thickening and blood vessel occlusion. Conclusion Adiponectin receptors expression in lung tissue is given priority to AdipoR1. High blood glucose may result in lung injury and decrease AdipoR1 expression and SOD activity.

Key words: adiponectin receptor, adiponectin, type 1 diabetes mellitus, type 2 diabetes mellitus