Purchase this article with an account.
Guoge Han, John P. Wood, Glyn Childlow, Teresa Mammone, Robert J. Casson; Mechanisms of Glucose Protection of Cultured Rat Retinal Cells from Experimental Anoxia. Invest. Ophthalmol. Vis. Sci. 2012;53(14):779.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Previous experiments have demonstrated that elevating vitreal glucose levels, either by short-term diabetes,or intraocular glucose delivery in rats rendered the retina resistant to subsequent metabolic insults, such as acute high-intraocluar pressure-induced ischaemic retinal injury or experimental glaucomatous optic neuropathy. The present study aimed to elucidate the mechanisms involved in this protective response in vitro.
Retinal cultures comprising neurons and glia were treated with the mitochondrial complex I inhibitor, rotenone (10nm-100μM), for up to 24 hours. Transporters for gluocse and monocarboxylates were respectively inhibited by specific blockers to test whether metabolic coupling was involved in the mechanism. In some cases glucose(25mM) or the alternate energy substrates, pyruvate or lactate, and/or inhibitors of glycolysis or the pentose phosphate pathway (PPP) were also applied.Analysis of cell viability was by immunocytochemistry, immunoblotting and cytotoxicity assays as well as by TUNEL for apoptosis detection. Other metabolic assessments were undertaken by determining alterations in cellular levels of ATP, reactive oxygen species (ROS) and NAD(P)H.
Rotenone concentration-dependently caused the preferential loss of neurons from retinal cultures; glial cells were also affected at higher concentrations (>1μM).Inhibition of transporters for glucose(cytochalasin 10μm) and monocarboxylates (4-CIN 1μm) caused the respective loss of glia or neurons in mixed retinal cell cultures.Cell loss was by apoptosis and necrosis and was preceded by a reduction of cellular ATP and NADH and an increase in ROS levels. Glucose (25mM), but not pyruvate or lactate, was able to dose-dependently counteract the detrimental effects of rotenone; this effect involved a reduction in ROS and an increase in cellular ATP/NAD(P)H and could partially be reversed by PPP or glycolysis inhibition.
Glucose was able to protect rat retinal cells from rotenone-induced toxicity. Glucose acted via the PPP and glycolytic pathways, and helped to maintain cellular ATP and NAD(P)H levels and to reduce the increase in ROS. These data have implications for treatment of retinal diseases which involve neuronal metabolic compromise.
This PDF is available to Subscribers Only