title: Antioxidant activity of tryptophan in rats under experimental endotoxic shock.
abstract: Tryptophan (TRP), the precursor of the scavenger or immunomodulator molecules melatonin (MLT) and picolinic acid, can be found in the diet; and could be an alternative nutritional supplement used to regulate the immune response in the generation of free radicals. In an experimental model, the systemic administration of lipopolysaccharide (LPS), to promote the synthesis of pro-inflammatory cytokines, reactive oxygen species, and antioxidant enzymes, was performed on adult female, pregnant and lactating rats fed with a diet of TRP content (0.5mg/100g protein). Lung tissue was evaluated for levels of the products of lipoperoxidation (LPO's), malonaldehyde (MDA) and 4-hydroxy alkenals (4-HDA); nitrites (NO2), glutathione peroxidase (Gpx) enzyme activity, and the serum concentration of interferon-gamma (IFN-gamma), which were measured in the following groups: control (CTRL), LPS, MLT, TRP, LPS plus MLT (LPS+MLT), and LPS plus TRP (LPS+TRP). Results showed that the lung tissue levels of MDA and 4-HDA in the LPS+TRP group were significantly lower than in the TRP group. Statistically significant differences were not observed in nitric oxide levels among the groups LPS+MLT and LPS+TRP compared to the group under endotoxic shock (LPS). The Gpx enzyme activity was modified in the LPS+MLT vs the LPS group, but the difference was not statistically significant. The LPS+MLT group showed a smaller serum concentration (98%) of IFN-gamma than the LPS group. Statistically significant differences were not observed among the animals of the LPS+TRP and the LPS groups.
authors.affiliation: Centro de Investigación Biomédica de Occidente, Instituto Mexicano del Seguro Social, Sierra Mojada 800, Colonia Independencia, CP: 44340, Guadalajara, Jalisco, Mexico. kurtbitzer@gmail.com
authors.forename: Oscar Kurt
authors.initials: OK
authors.lastname: Bitzer-Quintero
authors.forename: Airam Jenny
authors.initials: AJ
authors.lastname: Dávalos-Marín
authors.forename: Genaro Gabriel
authors.initials: GG
authors.lastname: Ortiz
authors.forename: Alma Rosa del Angel
authors.initials: AR
authors.lastname: Meza
authors.forename: Blanca Miriam
authors.initials: BM
authors.lastname: Torres-Mendoza
authors.forename: Ramón Gaxiola
authors.initials: RG
authors.lastname: Robles
authors.forename: Veronica Chaparro
authors.initials: VC
authors.lastname: Huerta
authors.forename: Carlos
authors.initials: C
authors.lastname: Beas-Zárate
mesh_terms: D000818:Animals; D000833:Animals, Suckling; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology*; D016207:Cytokines / Q000187:drug effects / Q000378:metabolism; D019587:Dietary Supplements; D004195:Disease Models, Animal; D005260:Female; D008070:Lipopolysaccharides; D008168:Lung / Q000187:drug effects / Q000276:immunology; D008550:Melatonin / Q000378:metabolism; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism; D012772:Shock, Septic / Q000188:drug therapy* / Q000276:immunology; D014364:Tryptophan / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D016207:Cytokines; D008070:Lipopolysaccharides; D017382:Reactive Oxygen Species; D014364:Tryptophan; D008550:Melatonin