Plasma corticosterone elevation inhibits the activation of nuclear factor kappa B (NFKB) in the Syrian hamster pineal gland

Autor(es)

Ferreira, Z. S. ^{[1, 2]} ; Bothorel, B. ^[2] ; Markus, R. P. ^[1] ; Simonneaux, V. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biociencias, Lab Cronofarmacol, BR-05508900 Sao Paulo - Brazil

^[2] CNRS, Inst Neurosci Cellulaires & Integrat, Dept Neurobiol Rhytmes, UPR 3212, Strasbourg - France

• Tipo de documento: Artigo Científico
• Fonte: STRESS-THE INTERNATIONAL JOURNAL ON THE BIOLOGY OF STRESS; v. 15, n. 3, p. 339-347, MAY 2012.
• Citações Web of Science: 8

Resumo

We evaluated how the mild stress-induced increase in endogenous corticosterone affected the pineal gland in Syrian hamsters (Mesocricetus auratus). The animals were maintained under constant light for 1 day, instead of a cycle of 14:10-h, to increase the circulating corticosterone levels during the daytime. The nuclear translocation of nuclear factor kappa B (NFKB), which is the pivotal transcription factor for stress and injury, presented a daily rhythm in normal animals. NFKB nuclear content increased linearly from the onset of light {[}Zeitgeber Time 0 (ZT0)] until ZT11 and decreased after ZT12 when the plasma corticosterone peak was detected in normal animals. However, the 24-h profiles of the two curves were different, and they did not clearly support an exclusive relationship between corticosterone levels and NFKB content. Therefore, we tested the effect of increased endogenous corticosterone through inducing mild stress by maintaining daytime illumination for one night. This stressful condition, which increased daytime corticosterone levels, resulted in a daytime decrease in NFKB nuclear content, and this was inhibited by mifepristone. Overall, this study shows that NFKB has a daily rhythm in Syrian hamster pineal glands and, by increasing endogenous corticosterone with a stressful condition, NFKB activity is regulated. Therefore, this study suggests that the pineal gland in the Syrian hamster is a sensor of stressful conditions. (AU)

• Processo FAPESP: 07/07871-6 - Eixo Imune-Pineal: produção endócrina e parácrina de melatonina em condições de injúria
• Beneficiário: Regina Pekelmann Markus
• Linha de fomento: Auxílio à Pesquisa - Temático
• Processo FAPESP: 06/57009-6 - Estudo funcional e molecular das vias de sinalizacao intracelular moduladas por lps em penealocitos de rato em cultura.
• Beneficiário: Zulma Felisbina da Silva Ferreira
• Linha de fomento: Auxílio à Pesquisa - Regular