Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
Department of Physiology, Federal University of São Paulo, São Paulo, Brazil.
Neuroendocrinology. 2022;112(2):115-129. doi: 10.1159/000516148. Epub 2021 Mar 26.
Melatonin, an indolamine mainly released from the pineal gland, is associated with many biological functions, namely, the modulation of circadian and seasonal rhythms, sleep inducer, regulator of energy metabolism, antioxidant, and anticarcinogenic. Although several pieces of evidence also recognize the influence of melatonin in the reproductive physiology, the crosstalk between melatonin and sex hormones is not clear. Here, we review the effects of sex differences in the circulating levels of melatonin and update the current knowledge on the link between sex hormones and melatonin. Furthermore, we explore the effects of melatonin on gonadal steroidogenesis and hormonal control in females. The literature review shows that despite the strong evidence that sex differences impact on the circadian profiles of melatonin, reports are still considerably ambiguous, and these differences may arise from several factors, like the use of contraceptive pills, hormonal status, and sleep deprivation. Furthermore, there has been an inconclusive debate about the characteristics of the reciprocal relationship between melatonin and reproductive hormones. In this regard, there is evidence for the role of melatonin in gonadal steroidogenesis brought about by research that shows that melatonin affects multiple transduction pathways that modulate Sertoli cell physiology and consequently spermatogenesis, and also estrogen and progesterone production. From the outcome of our research, it is possible to conclude that understanding the correlation between melatonin and reproductive hormones is crucial for the correction of several complications occurring during pregnancy, like preeclampsia, and for the control of climacteric symptoms.
褪黑素是一种主要由松果体分泌的吲哚胺，与许多生物学功能有关，即调节昼夜节律和季节性节律、诱导睡眠、调节能量代谢、抗氧化和抗癌。尽管有一些证据也承认褪黑素对生殖生理的影响，但褪黑素与性激素之间的相互作用尚不清楚。在这里，我们回顾了循环褪黑素水平的性别差异的影响，并更新了性激素与褪黑素之间联系的现有知识。此外，我们还探讨了褪黑素对女性性腺类固醇生成和激素控制的影响。文献综述表明，尽管有强有力的证据表明性别差异会影响褪黑素的昼夜节律模式，但报告仍然相当模糊，这些差异可能源于多种因素，如避孕药的使用、激素状态和睡眠剥夺。此外，关于褪黑素和生殖激素之间相互关系的特征还存在着不确定的争论。在这方面，有证据表明褪黑素在性腺类固醇生成中的作用，研究表明褪黑素影响调节支持细胞生理学进而影响精子发生的多种转导途径，以及雌激素和孕激素的产生。从我们的研究结果可以得出结论，理解褪黑素和生殖激素之间的相关性对于纠正妊娠期间发生的几种并发症（如子痫前期）以及控制更年期症状至关重要。
