RESUMO
Impairment of host defenses is chief among sleep deprivation outcomes, as evidenced by strikingly poor control over endogenous microorganisms. Interleukin [IL]-6 is a multifunctional cytokine. It is an inflammatory cytokine, which causes sickness manifestations. This cytokine might play a significant role in mediating the sleepiness and fatigue in the day after sleep deprivation. Leukocytosis has been a consistent finding in sleep deprivation inspite of the impaired immunity. Blood leukocyte differentials were performed to determine the cell types responsible for this finding of increased circulating white blood cell counts. Fatty acid composition of rodent diets can affect immune function as measured in vitro and in vivo and can modulates the immune response to different types of stress. This study was designed to investigate the effect of 4 days of sleep deprivation on the serum level of IL-6 and the differential count of white blood cells. Also to examine the effect of diet enriched with fat on the changes induced by sleep deprivation. Forty adult male albino rats were included in this study and were divided into 4 groups: Group I: [Control group] included 10 rats received standard rat chow and water and have normal sleep pattern, at -12 hours dark-light cycles. Group II: [Fat fed group] included 10 rats received standard rat chow enriched with corn oil and water, and have normal sleep pattern, at -12 hours dark-light cycles. Group III: [Sleep deprivation group] included 10 rats received standard rat chow and water, and was exposed to sleep deprivation. Group IV: [Fat fed and sleep deprived group] included 10 rats received standard rat chow enriched with corn oil and water, and was exposed to sleep deprivation in the same pattern as group III. Sleep deprivation was carried out by audio-visual mechanism. The results indicated decreased body weight, leukocytosis with neutrophilia and shift to the left, monocytosis and lymphopenia in sleep-deprived rats. The serum revealed an evolving pro-inflammatory state, as evidenced by high incidence of interleukin-6. Feeding the rats diet enriched with fat ameliorated the inflammatory state as evidenced by significant lower levels of IL-6 and partially corrected the change induced by sleep deprivation on the total and the differential blood count of WBCs. We can conclude that sleep deprivation has a considerable impact on the immune response. Nearly all of the immune-related events that emerged as responses to sleep deprivation have been implicated as a pro-inflammatory states that represents a risk factor for many diseases. Feeding sleep deprived rats a diet enriched in fatty acids ameliorated the effect of sleep deprivation on IL-6 secretion and partially attenuated the stimulation of inflammatory responses induced by sleep deprivation as indicated by partial correction of the body weight and WBCs count and composition