title: (-)-Epigallocatechin gallate attenuates NADPH-d/nNOS expression in motor neurons of rats following peripheral nerve injury.
abstract: BACKGROUND
  Oxidative stress and large amounts of nitric oxide (NO) have been implicated in the pathophysiology of neuronal injury and neurodegenerative disease. Recent studies have shown that (-)-epigallocatechin gallate (EGCG), one of the green tea polyphenols, has potent antioxidant effects against free radical-mediated lipid peroxidation in ischemia-induced neuronal damage. The purpose of this study was to examine whether EGCG would attenuate neuronal expression of NADPH-d/nNOS in the motor neurons of the lower brainstem following peripheral nerve crush. Thus, young adult rats were treated with EGCG (10, 25, or 50 mg/kg, i.p.) 30 min prior to crushing their hypoglossal and vagus nerves for 30 seconds (left side, at the cervical level). The treatment (pre-crush doses of EGCG) was continued from day 1 to day 6, and the animals were sacrificed on days 3, 7, 14 and 28. Nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry and neuronal nitric oxide synthase (nNOS) immunohistochemistry were used to assess neuronal NADPH-d/nNOS expression in the hypoglossal nucleus and dorsal motor nucleus of the vagus.
  
  
  RESULTS
  In rats treated with high dosages of EGCG (25 or 50 mg/kg), NADPH-d/nNOS reactivity and cell death of the motor neurons were significantly decreased.
  
  
  CONCLUSIONS
  The present evidence indicated that EGCG can reduce NADPH-d/nNOS reactivity and thus may enhance motor neuron survival time following peripheral nerve injury.
authors.affiliation: Department of Anatomy and Cell Biology, College of Medicine, China Medical University, Taichung, Taiwan. ihwei@mail.cmu.edu.tw
authors.forename: I-Hua
authors.initials: IH
authors.lastname: Wei
authors.forename: Hui-Chin
authors.initials: HC
authors.lastname: Tu
authors.forename: Chih-Chia
authors.initials: CC
authors.lastname: Huang
authors.forename: Mang-Hung
authors.initials: MH
authors.lastname: Tsai
authors.forename: Chi-Yu
authors.initials: CY
authors.lastname: Tseng
authors.forename: Jeng-Yung
authors.initials: JY
authors.lastname: Shieh
mesh_terms: D000818:Animals; D001933:Brain Stem / Q000187:drug effects* / Q000378:metabolism; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D016923:Cell Death / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D008297:Male; D009046:Motor Neurons / Q000187:drug effects* / Q000378:metabolism; D009249:NADP / Q000378:metabolism*; D009409:Nerve Crush; D018696:Neuroprotective Agents / Q000494:pharmacology*; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism*; D059348:Peripheral Nerve Injuries; D051381:Rats; D017208:Rats, Wistar
chemical_list: D018696:Neuroprotective Agents; D009249:NADP; D002392:Catechin; C045651:epigallocatechin gallate; D052248:Nitric Oxide Synthase Type I