• bevacizumab;
  • diabetes;
  • prevention;
  • retinal angiogenesis


Purpose:  To evaluate the efficacy of intravitreal injection of bevacizumab as a preventive intervention of vascular endothelial cell proliferation in the retina of diabetic rats.

Methods:  Fifty-four streptozotocin-induced diabetic Wistar rats were injected intravitreally with 3 µL (25 mg/mL) of bevacizumab into left eyes and 3 µL of saline into the right eyes. Immunohistochemistry and enzyme-linked immunosorbent assays for CD34 and VEGF were used to assess retinal angiogenesis, and transmission electron microscopy was used to evaluate the ultrastructure of retinal capillaries.

Results:  Retinal expression of VEGF was inhibited 1 week and 1 month after injection (P < 0.01, paired t-test), and the expression of CD34 was not obviously inhibited until 2 months after injection (P < 0.05, paired t-test). Using multiple comparisons between the left eyes of bevacizumab-treated rats, the VEGF expression before injection was higher than at 1 week or 1 month after injection (P < 0.05, Dunnett's t-test), and similar to 2 months after injection (P > 0.05, Dunnett's t-test). The amount of VEGF expression was higher 2 months after injection than 1 week or 1 month after injection, and also higher 1 week after injection compared with 1 month after injection (P < 0.05, Student–Newman–Keuls test). CD34 expression decreased more significantly 2 months after injection compared with before injection, 1 week or 1 month after injection (P < 0.05, Dunnett's t-test).

Conclusion:  A single intraocular injection of bevacizumab may be beneficial as a therapy for preventing retinal vascular endothelial cell growth in the eyes of diabetic rats.