title: Green tea (-)epigallocatechin-3-gallate reverses oxidative stress and reduces acetylcholinesterase activity in a streptozotocin-induced model of dementia.
abstract: Alzheimer's disease (AD) is the most prevalent form of dementia. Intracerebroventricular (ICV) infusion of streptozotocin (STZ) provides a relevant animal model of chronic brain dysfunction that is characterized by long-term and progressive deficits in learning, memory, and cognitive behavior, along with a permanent and ongoing cerebral energy deficit. Numerous studies on green tea epigallocatechin gallate (EGCG) demonstrate its beneficial effects on cognition and memory. As such, this study evaluated, for the first time, the effects of sub-chronic EGCG treatment in rats that were submitted to ICV infusion of STZ (3mg/kg). Male Wistar rats were divided into sham, STZ, sham+EGCG and STZ+EGCG groups. EGCG was administered at a dose of 10mg/kg/day for 4 weeks per gavage. Learning and memory was evaluated using Morris' Water Maze. Oxidative stress markers and involvement of the nitric oxide (NO) system, acetylcholinesterase activity (AChE) and glucose uptake were evaluated as well as glial parameters including S100B content and secretion and GFAP content. Our results show that EGCG was not able to modify glucose uptake and glutathione content, although cognitive deficit, S100B content and secretion, AChE activity, glutathione peroxidase activity, NO metabolites, and reactive oxygen species content were completely reversed by EGCG administration, confirming the neuroprotective potential of this compound. These findings contribute to the understanding of diseases accompanied by cognitive deficits and the STZ-model of dementia.
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-anexo, 90035-003, Porto Alegre, RS, Brazil.
authors.forename: Regina
authors.initials: R
authors.lastname: Biasibetti
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-anexo, 90035-003, Porto Alegre, RS, Brazil.
authors.forename: Ana Carolina
authors.initials: AC
authors.lastname: Tramontina
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-anexo, 90035-003, Porto Alegre, RS, Brazil.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Costa
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-anexo, 90035-003, Porto Alegre, RS, Brazil.
authors.forename: Márcio Ferreira
authors.initials: MF
authors.lastname: Dutra
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-anexo, 90035-003, Porto Alegre, RS, Brazil.
authors.forename: André
authors.initials: A
authors.lastname: Quincozes-Santos
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-anexo, 90035-003, Porto Alegre, RS, Brazil.
authors.forename: Patrícia
authors.initials: P
authors.lastname: Nardin
authors.affiliation: Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite, 500, 90050-170, Porto Alegre, RS, Brazil.
authors.forename: Caren Luciane
authors.initials: CL
authors.lastname: Bernardi
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-anexo, 90035-003, Porto Alegre, RS, Brazil.
authors.forename: Krista Minéia
authors.initials: KM
authors.lastname: Wartchow
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-anexo, 90035-003, Porto Alegre, RS, Brazil.
authors.forename: Paula Santana
authors.initials: PS
authors.lastname: Lunardi
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-anexo, 90035-003, Porto Alegre, RS, Brazil; Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Sarmento Leite, 500, 90050-170, Porto Alegre, RS, Brazil. Electronic address: casg@ufrgs.br.
authors.forename: Carlos-Alberto
authors.initials: CA
authors.lastname: Gonçalves
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000008:administration & dosage; D000975:Antioxidants / Q000494:pharmacology*; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D003071:Cognition / Q000187:drug effects; D003704:Dementia / Q000139:chemically induced* / Q000378:metabolism*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D007276:Injections, Intraventricular; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D009414:Nerve Growth Factors / Q000378:metabolism; D009457:Neuroglia / Q000378:metabolism; D018696:Neuroprotective Agents; D009569:Nitric Oxide / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000378:metabolism; D013028:Space Perception / Q000187:drug effects; D013311:Streptozocin / Q000008:administration & dosage; D013662:Tea / Q000737:chemistry*
chemical_list: D000903:Antibiotics, Antineoplastic; D000975:Antioxidants; D005904:Glial Fibrillary Acidic Protein; D009414:Nerve Growth Factors; D018696:Neuroprotective Agents; D017382:Reactive Oxygen Species; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C579158:S100b protein, rat; D013662:Tea; D009569:Nitric Oxide; D013311:Streptozocin; D002392:Catechin; C045651:epigallocatechin gallate; D005979:Glutathione Peroxidase; D000110:Acetylcholinesterase; D005978:Glutathione; D005947:Glucose