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Deregulated Brain's Central Clock Management on Sleep-Wake Behavior in Women With Polycystic Ovary Syndrome:
1Vali-E-Asr Reproductive Health Research Center, Family Health Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
Abstract:
The aim of this narrative review is to investigate the reciprocal correlation between melatonin through the brain's central clock management on sleep-wake behavior in women with polycystic ovary syndrome (PCOS). Biological clocks are genetically programmed physiological systems that permit organisms to live in harmony with natural rhythms. The most important function of a biological clock is to regulate overt circadian biological rhythms. Circadian rhythms orchestrate the body's rhythmic physiologic functions like sleep-wake and menstruation cycle. Stress hormones, beta-endorphins, and melatonin which can easily affect the woman's reproductive system. For example, amplitude changes in the luteal phase are one of the results of menstrual-related disorders that occur through this circadian fluctuation. Many reports indicate that levels of melatonin and stress hormones are altered in women with PCOS. The melatonin metabolites are significantly raised in the level of night-time urinary in women with PCOS, which is associated with a significant reduction of sleep quality compared to normal women. The result of this narrative review showed the circadian rhythm as a normal coordinated function is a regulator of the natural structure of sleep-wake architecture. Disruption of this natural pattern can lead to phasic activation of the HPA axis, which increases the continuation of circadian activation; which there is in women with PCOS.
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