Elevation by Oxidative Stress and Aging of Hypothalamic-Pituitary-Adrenal Activity in Rats and Its Prevention by Vitamin E

• Kobayashi Naoko

  Division of Biochemistry, Shibaura Institute of Technology

• Machida Taiji

  Division of Biochemistry, Shibaura Institute of Technology

• Takahashi Takeyuki

  Division of Biochemistry, Shibaura Institute of Technology

• Takatsu Hirokatsu

  Division of Biochemistry, Shibaura Institute of Technology

• Shinkai Tadashi

  Tokyo Metropolitan Institute of Gerontology

• Abe Kouichi

  Vitamin E Information and Technology Section, Eisai Co. Ltd.

• Urano Shiro

  Division of Biochemistry, Shibaura Institute of Technology

抄録

The present study was conducted in order to determine whether oxidative stress during aging involves dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis in association with the emergence of cognitive deficits. When young rats were subjected to oxidative stress in the form of hyperoxia, thiobarbituric acid reactive substances, conjugated diene and lipid hydroperoxides increased markedly in the HPA axis. Vitamin E inhibited such increases in lipid peroxides in each organ. Levels of corticotrophin-releasing hormone in the hypothalamus and plasma levels of adrenocorticotrophic hormone and corticosterone were markedly elevated in young rats exposed to hyperoxia. However, young rats fed vitamin E-supplemented diets showed no abnormal hormone secretion, even after being subjected to hyperoxia. Furthermore, glucocorticosteroid receptors (GR) in pyramidal cells in the Cornus ammonis 1 region of the hippocampus in young rats were markedly decreased by oxidative stress. Similar phenomena were also observed in normal aged rats and young rats fed vitamin E-deficient diet kept in a normal atmosphere. Vitamin E supplementation prevented the decrease in GR in the hippocampus and the increase in corticosterone secretion caused by hyperoxia. These results suggest that oxidative stress induces oxidative damage in the hippocampus and the HPA axis during aging, resulting in a cognitive deficit in rats, and that negative-feedback inhibition on HPA activity was markedly dampened due to an increase in corticosterone levels caused by loss of GR.<br>

収録刊行物

• Ｊｏｕｒｎａｌ　ｏｆ　Ｃｌｉｎｉｃａｌ　Ｂｉｏｃｈｅｍｉｓｔｒｙ　ａｎｄ　Ｎｕｔｒｉｔｉｏｎ

  Ｊｏｕｒｎａｌ　ｏｆ　Ｃｌｉｎｉｃａｌ　Ｂｉｏｃｈｅｍｉｓｔｒｙ　ａｎｄ　Ｎｕｔｒｉｔｉｏｎ 45 (2), 207-213, 2009

  一般社団法人　日本酸化ストレス学会

キーワード

• Oxidative stress
• HPA activity
• corticosteroid receptor
• aging
• vitamin E

詳細情報

• CRID: 1390282679649225728
• NII論文ID: 130004466581
• DOI: 10.3164/jcbn.09-33
• COI: 1:CAS:528:DC%2BD1MXhtlWrsbjN
• ISSN: 18805086
• ISSN: 09120009
• 本文言語コード: en
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可