Redox and Antioxidant Modulation of Circadian Rhythms: Effects of Nitroxyl, N-Acetylcysteine and Glutathione.
Molecules
; 26(9)2021 Apr 26.
Article
en En
| MEDLINE
| ID: mdl-33925826
ABSTRACT
The circadian clock at the hypothalamic suprachiasmatic nucleus (SCN) entrains output rhythms to 24-h light cycles. To entrain by phase-advances, light signaling at the end of subjective night (circadian time 18, CT18) requires free radical nitric oxide (NOâ¢) binding to soluble guanylate cyclase (sGC) heme group, activating the cyclic guanosine monophosphate (cGMP)-dependent protein kinase (PKG). Phase-delays at CT14 seem to be independent of NOâ¢, whose redox-related species were yet to be investigated. Here, the one-electron reduction of NO⢠nitroxyl was pharmacologically delivered by Angeli's salt (AS) donor to assess its modulation on phase-resetting of locomotor rhythms in hamsters. Intracerebroventricular AS generated nitroxyl at the SCN, promoting phase-delays at CT14, but potentiated light-induced phase-advances at CT18. Glutathione/glutathione disulfide (GSH/GSSG) couple measured in SCN homogenates showed higher values at CT14 (i.e., more reduced) than at CT18 (oxidized). In addition, administration of antioxidants N-acetylcysteine (NAC) and GSH induced delays per se at CT14 but did not affect light-induced advances at CT18. Thus, the relative of NO⢠nitroxyl generates phase-delays in a reductive SCN environment, while an oxidative favors photic-advances. These data suggest that circadian phase-locking mechanisms should include redox SCN environment, generating relatives of NOâ¢, as well as coupling with the molecular oscillator.
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Banco de datos:
MEDLINE
Asunto principal:
Oxidación-Reducción
/
Ritmo Circadiano
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Antioxidantes
Idioma:
En
Año:
2021
Tipo del documento:
Article