title: Nitric oxide pathway activity modulation alters the protective effects of (-)Epigallocatechin-3-gallate on reserpine-induced impairment in rats.
abstract: Reserpine (RES) has been reported to increase the brain's neural oxidative stress and cause cognitive dysfunction. Having powerful antioxidative properties, green tea catechins, especially (-)epigallocatechin-3-gallate (EGCG), are able to protect against many oxidative injuries. In this study, we examined the protecting properties of EGCG on RES-induced impairment of short-term memory in three-month-old male Wistar rats. RES (1mg/kg i.p.) induced memory impairment (p<0.001) as evaluated by the social recognition task. EGCG treatment (100mg/kg i.p. for 7days, starting 6days before RES injection) was able to improve the impaired memory caused by RES. RES treatment increased the nitric oxide (NO) level and lipid peroxidation (LPO) production, and decreased the antioxidation power in hippocampi. EGCG treatment was able to counteract the RES-induced NO level and LPO production, as well as enhanced the hippocampal antioxidation power in RES-treated rats. In order to examine the implication of NO pathway activity in RES treatment, either NO precursor (L-arginine; L-A) or NO synthase inhibitor (L-NAME; L-N) was co-pretreated with EGCG; NO precursor treatment eliminated the protective effect of EGCG, in contrast to that NO synthase inhibitor treatment significantly increased the EGCG effects on cognitive and biochemical protection in RES-treated rats. These results suggested that the NO pathway was implicated, at least in part, in the RES-induced impairment, as well as in the protective effect of EGCG in treating RES-induced impairment of memory. The above evidence provides a clinically relevant value for EGCG in preventing RES-induced cognitive dysfunction.
authors.affiliation: Division of Neurosurgery, Department of Surgery, Taitung br. of Mackay Memorial Hospital, Taitung 95054, Taiwan, ROC.
authors.forename: Cheng-Neng
authors.initials: CN
authors.lastname: Chen
authors.affiliation: Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei 10608, Taiwan, ROC.
authors.forename: Kuo-Chi
authors.initials: KC
authors.lastname: Chang
authors.affiliation: Department of Neurosurgery, Mackay Memorial Hospital, Taipei 10449, Taiwan, ROC.
authors.forename: Rui-Feng
authors.initials: RF
authors.lastname: Lin
authors.affiliation: Department of Anesthesia, En Chu Kon Hospital, Sanshia District, New Taipei City 23702, Taiwan, ROC; Department of Optometry, Yuanpei University, Hsinchu 30015, Taiwan, ROC.
authors.forename: Mao-Hsien
authors.initials: MH
authors.lastname: Wang
authors.affiliation: Department of Anesthesia, En Chu Kon Hospital, Sanshia District, New Taipei City 23702, Taiwan, ROC.
authors.forename: Ruoh-Lan
authors.initials: RL
authors.lastname: Shih
authors.affiliation: Department of Anesthesiology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei 11101, Taiwan, ROC; School of Medicine, Fu Jen Catholic University, New Taipei City 24205, Taiwan, ROC.
authors.forename: Hsiang-Chien
authors.initials: HC
authors.lastname: Tseng
authors.affiliation: Department of Psychiatry, Yuan-Shan br. of Taipei Veteran General Hospital, Yilan County 26604, Taiwan, ROC.
authors.forename: Hung-Sheng
authors.initials: HS
authors.lastname: Soung
authors.affiliation: Department of Neurosurgery, Mackay Memorial Hospital, Taipei 10449, Taiwan, ROC; Graduate Institute of Injury Prevention and Control, Taipei Medical University, Taipei 11031, Taiwan, ROC. Electronic address: dschang580704@yahoo.com.tw.
authors.forename: Cheng-Chia
authors.initials: CC
authors.lastname: Tsai
mesh_terms: D000818:Animals; D001120:Arginine / Q000494:pharmacology; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D004192:Discrimination, Psychological / Q000187:drug effects; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005106:Exploratory Behavior / Q000187:drug effects; D005978:Glutathione / Q000378:metabolism; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D008569:Memory Disorders / Q000139:chemically induced / Q000188:drug therapy*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D018696:Neuroprotective Agents / Q000494:pharmacology / Q000627:therapeutic use; D009569:Nitric Oxide / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012110:Reserpine / Q000633:toxicity; D015398:Signal Transduction / Q000187:drug effects*; D012903:Smell / Q000187:drug effects; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D018696:Neuroprotective Agents; D009569:Nitric Oxide; D012110:Reserpine; D002392:Catechin; D001120:Arginine; C045651:epigallocatechin gallate; D013482:Superoxide Dismutase; D005978:Glutathione; D019331:NG-Nitroarginine Methyl Ester
keywords: (−)Epigallocatechin-3-gallate; Memory; Nitric oxide; Reserpine