Obstructive sleep apnea syndrome and circadian rhythms of hormones and cytokines.

Abstract

Several cytokines exhibit a high degree of temporal regulation as well as somnogenic potency (e.g., interleukin-1 [IL-1], tumor necrosis factor-alpha [TNF-alpha]). Seeking the underlying cause of obstructive sleep apnea syndrome (OSAS), we investigated whether circadian rhythms of cytokine release were altered in 10 patients with OSAS. Ten healthy volunteers served as the control population. Seven of the 10 OSAS patients were reexamined after 3 mo of therapy with nasal continuous positive airway pressure (nCPAP) mask ventilation. Circadian cytokine release (IL-1, IL-6, gamma-interferon [gamma-IFN], TNF-alpha) was investigated ex vivo by short-term culture of blood samples. The circadian rhythm of TNF-alpha release was significantly disturbed in OSAS patients: nocturnal physiologic peaks in this cytokine had almost disappeared and an additional daytime peak had developed. Circadian variations in IL-1, IL-6, and gamma-IFN, and in the immunoregulatory hormones melatonin and cortisol, did not differ from those in the controls. Because TNF-alpha is a known modulator of sleep, and nCPAP therapy did not normalize TNF rhythms, we assume that TNF-alpha could well play a pathophysiologic role in OSAS. Further studies should be directed at whether a physiopathologic and/or pathogenic link exists between TNF-alpha and OSAS.

Continuous Positive Airway Pressure Treatment Increases Serum Vitamin D Levels in Male Patients with Obstructive Sleep Apnea

“…In fact, nCPAP is the treatment of choice to improve several internal parameters in patients with OSA. [14][15][16][17][18] Vitamin D has pleiotropic effects and plays major roles in an extended range of organ functions and disorders. 7 Vitamin D is a fat-soluble secosteroid hormone which undergoes two hydroxylation reactions, first in the liver and second in the kidney.…”

Low- versus High-Baseline Epinephrine Output Shapes Opposite Innate Cytokine Profiles: Presence of Lewis- and Fischer-Like Neurohormonal Immune Phenotypes in Humans?

“…T he production of cytokines associated with innate immunity shows large interindividual variations (1)(2)(3)(4). This phenomenon may have an important clinical relevance since recent evidence indicates that individuals with relatively high or low pro-and anti-inflammatory cytokine profiles have an increased risk or resistance to a number of immune-related diseases (4 -8).…”

Sleep Apnea and its Association with the Stress System, Inflammation, Insulin Resistance and Visceral Obesity

“…Plasma and urinary catecholamines measured during the nighttime, and surge of sympathetic nerve activity determined by microneurography, are elevated in patients with OSA compared to obese controls (16,17). However, the limited existing literature has failed to detect any differences in plasma cortisol levels between sleep apneics and controls (18). Most studies have focused on the effects of CPAP on cortisol with conflicting data (19)(20)(21)(22)(23).…”