Effects of dopamine on oxidative stress and VEGF expression in retinal tissues of rats with diabetic retinopathy model / 国际生物医学工程杂志

ABSTRACT

Objective:To investigate the effect of dopamine on oxidative stress and vascular endothelial growth factor (VEGF) expression in the retinal tissue of diabetic retinopathy (DR) model rats.Methods:Ninety rats were randomly divided into three groups the control group, the model group, and the dopamine group, with 30 rats in each group. In the dopamine group, the DR model was established by a high-sugar and high-fat diet for four consecutive weeks, and no drug intervention was given to the control or model groups. The eyes of rats in the dopamine group were injected intravitreally with 50 mg/kg dopamine solution. The retinal tissues of the rats in the three groups were observed under a light microscope after hematoxylin-eosin staining. The levels of catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA), monocyte chemotactic protein-1 (MCP-1), interleukin-6 (IL-6), and VEGF were detected by enzyme-linked immunosorbent assay (ELISA) in the retinal tissues of the rats in the three groups. Western blot was used to detect VEGF expression in the three groups of rats.Results:In the control rats, the inner retinal border membrane was flat, with fewer neovascular endothelial cells protruding into the vitreous, and no neovascularization connected to the inner membrane reaching the intravitreous was observed. Compared with the control group, rats in the model group had more vascular endothelial cells breaking through the inner border membrane, and significant cellular proliferation was observed under the inner border membrane. Compared with the model group, rats in the dopamine group had a less flat inner retinal border membrane, fewer neovascularized endothelial cells protruding into the vitreous, and less cellular proliferation under the inner border membrane. Compared with the control group, CAT and SOD levels were decreased, while MDA, MCP-1, IL-6, and VEGF levels were increased in the model group, and the differences between the two groups were statistically significant (all P < 0.05). Compared with the model group, CAT and SOD levels were increased in the dopamine group, while MDA, MCP-1, IL-6, and VEGF levels were decreased, and the differences between the two groups were statistically significant (all P < 0.05). Conclusions:Dopamine up-regulated CAT and SOD levels and down-regulated MDA, MCP-1, IL-6 levels, and VEGF expression in the retinal tissues of DR rats.