Purchase this article with an account.
H. Zong, A. Madden, A. Limb, P. Yong, M. Ward, A. Stitt; The Dimerisation of the Receptor for Advanced Glycation End-Products (RAGE) Is Essential for AGE-Induced Signaling in Diabetic Retinopathy. Invest. Ophthalmol. Vis. Sci. 2009;50(13):5365.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Accumulation of advanced glycation end-products (AGEs) and activation of the pro-inflammatory receptor for AGEs (RAGE) has been implicated in diabetic microvascular disease. S100B, beta-amyloid, HMGB1 and AGEs can function as RAGE ligands but the pathological consequences of RAGE activation in the diabetic retina remain unelucidated. This study has analysed RAGE expression and signaling responses in diabetic retina in vivo and in retinal Muller glia in vitro.
STZ-induced diabetes was maintained in rats for 4 months. Cryosections of retina were analysed for RAGE, S100B and AGE immunoreactivity. Diabetes-mediated activation of GFAP in Muller glia was also assessed. RAGE cDNA was amplified and used to construct RAGE expression plasmids. Co-immunoprecipitation (CoIP) was performed using cell lysates from transfected MIOM1 cells, a human Muller cell line. Cell surface proteins were crosslinked by BS3. The protein and mRNA expression of cytokines was measured by protein chipset array and also by real-time RT-PCR.
Co-localisation and increased expression level of S100B, RAGE and various AGE adducts were detected in Muller glia of diabetic retina compared to normal retina. In MIOM1 cells, CoIP assay showed RAGE self-interaction, and that the IgV domain, which is the potential ligand binding domain, was responsible for RAGE self-interaction. RAGE dimers were detected in BS3-crosslinked MIOM1 cells. S100B and AGEs induced the expression of IL6, IL8, VEGF, IFN-γ and MCP1 (p<0.01), an effect modulated by RAGE.
RAGE and its ligands are increased in diabetic retina, especially in Muller glia. RAGE modulates cytokine responses from Muller cells in vitro, Our data also indicate that dimerisation of RAGE can regulate the signaling response, with consequences for pro-inflammatory pathology in diabetic retinopathy.
This PDF is available to Subscribers Only