Melatonin is the primary circadian output signal from the brain and is mainly synthesized in pinealocytes. The rhythm and secretion of melatonin are under the control of an endogenous oscillator located in the SCN or the master biological clock. Disruptions in circadian rhythms by shift work, aging, or light at night are associated with bone loss and increased fracture risk. Restoration of nocturnal melatonin peaks to normal levels or therapeutic levels through timed melatonin supplementation has been demonstrated to provide bone-protective actions in various models. Melatonin is a unique molecule with diverse molecular actions targeting melatonin receptors located on the plasma membrane or mitochondria or acting independently of receptors through its actions as an antioxidant or free radical scavenger to stimulate osteoblastogenesis, inhibit osteoclastogenesis, and improve bone density. Its additional actions on entraining circadian rhythms and improving quality of life in an aging population coupled with its safety profile make it an ideal therapeutic candidate for protecting against bone loss in susceptible populations. The intent of this review is to provide a focused discussion on bone loss and disorders of the bone as it relates to melatonin and conditions that modify melatonin levels with the hope that future therapies include those that include melatonin and correct those factors that modify melatonin levels like circadian disruption.

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褪黑激素对骨骼的影响：用作治疗骨质流失的意义

褪黑激素是大脑的主要昼夜节律输出信号，主要在松果体细胞中合成。褪黑激素的节律和分泌受位于 SCN 或主生物钟中的内源性振荡器的控制。轮班工作、衰老或夜间光线导致的昼夜节律中断与骨质流失和骨折风险增加有关。通过定时补充褪黑激素将夜间褪黑激素峰值恢复到正常水平或治疗水平已被证明可在各种模型中提供骨骼保护作用。褪黑激素是一种独特的分子，具有多种分子作用，靶向位于质膜或线粒体上的褪黑激素受体，或通过其作为抗氧化剂或自由基清除剂的作用刺激成骨细胞生成，独立于受体发挥作用，抑制破骨细胞生成，提高骨密度。其在调节昼夜节律和改善老龄化人群生活质量方面的额外作用及其安全性使其成为防止易感人群骨质流失的理想治疗候选药物。这篇综述的目的是集中讨论骨质流失和骨骼疾病，因为它与褪黑激素和改变褪黑激素水平的疾病有关，希望未来的疗法包括那些包括褪黑激素的疗法，并纠正那些改变褪黑激素水平的因素，如昼夜节律紊乱。其在调节昼夜节律和改善老龄化人群生活质量方面的额外作用及其安全性使其成为防止易感人群骨质流失的理想治疗候选药物。本综述的目的是重点讨论骨质流失和骨骼疾病，因为它与褪黑激素和改变褪黑激素水平的病症有关，希望未来的疗法包括那些包括褪黑激素的疗法，并纠正那些改变褪黑激素水平的因素，如昼夜节律紊乱。其在调节昼夜节律和改善老龄化人群生活质量方面的额外作用及其安全性使其成为防止易感人群骨质流失的理想治疗候选药物。本综述的目的是重点讨论骨质流失和骨骼疾病，因为它与褪黑激素和改变褪黑激素水平的病症有关，希望未来的疗法包括那些包括褪黑激素的疗法，并纠正那些改变褪黑激素水平的因素，如昼夜节律紊乱。