Neuroprotective effects of Epigallocatechin-3-gallate (EGCG) in optic nerve crush model in rats.
Epigallocatechin-3-gallate (EGCG), the major catechin found in green tea, is a powerful antioxidant and has anti-inflammatory with neuroprotective potential. This study aims to investigate the neuroprotective effects of EGCG in an optic nerve crush (ONC) model in rats. Seventy-two Wistar rats were randomly divided into four groups: normal control (group A), sham operation+EGCG (group B), ONC+vehicle (group C), and ONC+EGCG (group D). The rats were treated intraperitoneally and orally with either vehicle or EGCG (25 mg/kg, injected daily for 5 days and 2 mg/kg orally daily afterwards). Two days after the first injection, an ONC injury was performed by using a micro optic nerve clipper with 40 g power at approximately 2 mm from the optic nerve head for 60 s. Fluorogold was injected into the bilateral superior colliculi 5 days before sacrifice and fluorescent gold-labelled retinal ganglion cells (RGCs) were counted under fluorescence microscopy on days 7, 14 and 28 after ONC. The expression of Neurofilament triplet L (NF-L) was measured via immunohistochemical and Western blotting analysis. In group C, a progressive loss of RGCs was observed after ONC. In contrast, the density of RGCs was significantly higher in group D (p=0.009, independent samples t-test) on day 7 after ONC, and statistical differences were obtained on days 14 and 28 (p=0.026 and p=0.019, respectively, independent samples t-test). The results of immunohistochemical and Western blotting analysis showed significantly higher NF-L protein expression in group D in comparison with group C on days 7, 14 and 28 after ONC. These findings suggest that there are protective effects of EGCG on RGCs after ONC, indicating EGCG might be a potential therapeutic agent for optic nerve diseases.
Xie
Jun
J
Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, PR China.
Jiang
Libin
L
Zhang
Ting
T
Jin
Yulan
Y
Yang
Dongmei
D
Chen
Fei
F
D000818:Animals; D002392:Catechin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D002452:Cell Count; D002470:Cell Survival / Q000187:drug effects; D004195:Disease Models, Animal; D005260:Female; D009409:Nerve Crush; D016900:Neurofilament Proteins / Q000378:metabolism; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D020221:Optic Nerve Injuries / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012160:Retina / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D012165:Retinal Ganglion Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D013997:Time Factors; D016896:Treatment Outcome
D016900:Neurofilament Proteins; D018696:Neuroprotective Agents; C044882:neurofilament protein L; D002392:Catechin; C045651:epigallocatechin gallate