title: Oxidative damage and brain concentrations of free amino acid in chicks exposed to high ambient temperature.
abstract: High ambient temperatures (HT) reduce food intake and body weight in young chickens, and HT can cause increased expression of hypothalamic neuropeptides. The mechanisms by which HT act, and the effects of HT on cellular homeostasis in the brain, are however not well understood. In the current study lipid peroxidation and amino acid metabolism were measured in the brains of 14 d old chicks exposed to HT (35 °C for 24- or 48-h) or to control thermoneutral temperature (CT; 30 °C). Malondialdehyde (MDA) was measured in the brain to determine the degree of oxidative damage. HT increased body temperature and reduced food intake and body weight gain. HT also increased diencephalic oxidative damage after 48 h, and altered some free amino acid concentrations in the diencephalon. Diencephalic MDA concentrations were increased by HT and time, with the effect of HT more prominent with increasing time. HT altered cystathionine, serine, tyrosine and isoleucine concentrations. Cystathionine was lower in HT birds compared with CT birds at 24h, whilst serine, tyrosine and isoleucine were higher at 48 h in HT birds. An increase in oxidative damage and alterations in amino acid concentrations in the diencephalon may contribute to the physiological, behavioral and thermoregulatory responses of heat-exposed chicks.
authors.affiliation: Division for Arts and Science, Faculty of Arts and Science, Kyushu University, Fukuoka 819-0395, Japan. Electronic address: vc-sur@artsci.kyushu-u.ac.jp.
authors.forename: Vishwajit S
authors.initials: VS
authors.lastname: Chowdhury
authors.affiliation: Laboratory of Regulation in Metabolism and Behavior, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Shozo
authors.initials: S
authors.lastname: Tomonaga
authors.affiliation: Laboratory of Regulation in Metabolism and Behavior, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Taro
authors.initials: T
authors.lastname: Ikegami
authors.affiliation: Laboratory of Regulation in Metabolism and Behavior, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Edi
authors.initials: E
authors.lastname: Erwan
authors.affiliation: Laboratory of Regulation in Metabolism and Behavior, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ito
authors.affiliation: Institute for Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand.
authors.forename: John F
authors.initials: JF
authors.lastname: Cockrem
authors.affiliation: Laboratory of Regulation in Metabolism and Behavior, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Furuse
mesh_terms: D000222:Adaptation, Physiological; D000596:Amino Acids / Q000097:blood*; D000818:Animals; D001831:Body Temperature; D001835:Body Weight; D002645:Chickens / Q000378:metabolism*; D004027:Diencephalon / Q000378:metabolism*; D004435:Eating; D018869:Heat-Shock Response; D006358:Hot Temperature; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress
chemical_list: D000596:Amino Acids; D008315:Malondialdehyde
keywords: Brain; Chick; Food intake; Free amino acids; High ambient temperature; Oxidative damage