Premium
Neuroprotective effect of epigallocatechin‐3‐gallate against N ‐methyl‐D‐aspartate‐induced excitotoxicity in the adult rat retina
Author(s) -
Chen Fei,
Jiang Libin,
Shen Ceying,
Wan Hongfei,
Xu Liang,
Wang Ningli,
Jonas Jost B.
Publication year - 2012
Publication title -
acta ophthalmologica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.534
H-Index - 87
eISSN - 1755-3768
pISSN - 1755-375X
DOI - 10.1111/j.1755-3768.2012.02502.x
Subject(s) - excitotoxicity , nmda receptor , saline , neuroprotection , intraperitoneal injection , retina , ganglion cell layer , glutamate receptor , retinal , pharmacology , endocrinology , medicine , chemistry , anesthesia , ophthalmology , biology , receptor , neuroscience
. Purpose: Epigallocatechin‐3‐gallate (EGCG), the major polyphenol of green tea, has been suggested to reduce glutamate excitotoxicity. We therefore investigated the potentially protective effects of EGCG against N ‐methyl‐ d ‐aspartate (NMDA)‐induced excitotoxicity in the retina. Methods: Female Wistar rats ( n = 171) were divided into a normal control group ( n = 9); saline control group with intravitreal saline injections ( n = 54); NMDA control group with an intravitreal NMDA injection and intraperitoneal saline injections ( n = 54); and NMDA study group ( n = 54) receiving an intravitreal NMDA injection plus intraperitoneal EGCG (25 mg/kg) injections. Starting at 2 days prior to the intravitreal NMDA injection, the intraperitoneal injections were performed daily for the whole study period. At 12 hr, 1, 2, 3 days, 1 and 2 weeks after the intravitreal NMDA injection, the animals were killed. We counted the neurons in the retinal ganglion cell layer (GCL) on histological sections, measured the thickness of Thy‐1 immunoreactivity and assessed the expression of Thy‐1 mRNA by real‐time polymerase chain reaction. Results: At all time‐points, GCL cell density, thickness of Thy‐1 immunoreactivity and expression of Thy‐1 mRNA were significantly (all p < 0.05) lower in the NMDA control group than in the NMDA study group, in which the parameters were significantly (all p < 0.05) lower than in the saline control group and the normal control group. In both groups with an intravitreal NMDA injection, GCL cell density, thickness of Thy‐1 immunoreactivity and expression of Thy‐1 mRNA decreased significantly with increasing follow‐up time. Conclusions: Intraperitoneal application of EGCG resulted in a significantly less marked NMDA‐associated loss of retinal ganglion cells.