Abstract
Purpose: :
We have previously shown that increased expression of activated TGF–ß1 causes similar ocular complications found in diabetic patients, including abnormal retinal blood vessels due to disrupted recruitment of retinal pericytes, lens cataracts, and corneal opacities. The long–term goal of this study is to determine if inflammatory cytokines cause the activation of transforming growth factor beta 1 (TGF–b1) that is observed in diabetic patients. The purpose of this study is to determine whether or not cytokines such as tumor necrosis factor alpha (TNF–α) can cause TGF–ß1 activation in vivo.
Methods: :
Recombinant TNF–α was injected into the vitreous of BalbC mice. Two days after injection, TGF–ß1 was measured by ELISA specific for activated TGF–ß1. Vascular permeability was also used to monitor the integrity of the blood retinal barrier.
Results: :
Intravitreal injections of TNF–α led to activation of TGF–ß1 when compared to PBS injected controls.
Conclusions: :
Our previous studies have shown that elevated expression of activated TGF–ß1 causes disruptions in the retinal vasculature including failure of pericyte recruitment. Data from this study suggest that inflammation induced by diabetes may result in activation of endogenous TGF–ß1.
Keywords: diabetic retinopathy • cytokines/chemokines • inflammation