Melatonin is a hormone produced in animals by the pineal gland and in plants under stress. Melatonin research has expanded rapidly, affecting an impressive enhancement in the understanding of its functions in plants and animals. However, far less focus has been directed to clarifying the nature of melatonin dose-response relationships. Here, we provide substantial evidence of melatonin-induced biphasic dose-response relationships from a series of independent studies involving plant and animal models. The characteristics of these dose responses are similar to those of the broad toxicological and pharmacological hormesis literature. Our analysis suggests that melatonin, in coordination with the circadian rhythms, is involved in stress adaptive responses, and may act as a conditioning agent protecting organisms against subsequent health threats within an hormetic framework. Incorporation of melatonin-induced hormesis in research protocols has the potential to enhance the treatment of neuropsychiatric diseases, cancers, and other animal diseases, as well as protection against environmental stress and to increase plant productivity.

褪黑激素是松果体在动物体内和植物在压力下产生的一种激素。褪黑激素的研究迅速发展，对植物和动物功能的认识有了显着提高。然而，很少有焦点集中在阐明褪黑激素剂量反应关系的本质上。在这里，我们从涉及植物和动物模型的一系列独立研究中提供了褪黑激素诱导的双相剂量反应关系的实质性证据。这些剂量反应的特征类似于广泛的毒理学和药理学毒理学文献。我们的分析表明，褪黑素与昼夜节律有关，参与了压力适应性反应，并可以充当调理剂，以保护生物体在紧缩的框架内免受随后的健康威胁。将褪黑激素诱导的兴奋剂纳入研究方案中，具有增强神经精神疾病，癌症和其他动物疾病的治疗，以及对抗环境压力和提高植物生产力的潜力。