Abstract
Purpose :
To investigate the changes in inflammatory and angiogenic cytokine levels in aqueous humor and vitreous body after intravitreal injection of bevacizumab (IVB) or triamcinolone (IVTA), as well as sub-Tenon injection of triamcinolone (STTA) after retinal laser photocoagulation in rabbits.
Methods :
Pigmented rabbits were treated with retinal laser photocoagulation and divided into 4 groups, namely Control (no additional treatment), IVB, IVTA or STTA accordingly. Samples of vitreous and aqueous humor were collected on post-treatment days 0, 1, 7 and 14. The levels of intraocular vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), intercellular adhesion molecule-1 (ICAM-1) and monocyte chemotactic protein-1 (MCP-1) were measured using an immunoassay.
Results :
The levels of VEGF, IL-6, ICAM-1 and MCP-1 were significantly elevated 1 day after laser treatment (P<0.05). IVTA and STTA significantly reduced the increase in the levels of VEGF, IL-6, ICAM-1 and MCP-1, while IVB reduced that of VEGF only in aqueous humor and vitreous body (P<0.05, unpaired student t-test). The protein amount in the aqueous humor transiently increased 1 day after laser, and was significantly prevented by IVTA or STTA but not IVB.
Conclusions :
Data showed that bevacizumab only reduced intraocular VEGF after laser, while triamcinolone suppressed both the expression of VEGF and proinflammatory cytokines. We propose that these cytokine profiles may play an important role in the pathogenesis of inflammation after photocoagulation and the underlying mechanism of treatment with anti-VEGF drug and corticosteroids.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.