Wound Healing and Regenerative Medicine Research Program, Department of Dermatology and Cutaneous Surgery, University of Miami Miller Medical School, Miami, Florida, USA.
Wound Healing and Regenerative Medicine Research Program, Department of Dermatology and Cutaneous Surgery, University of Miami Miller Medical School, Miami, Florida, USA.
J Invest Dermatol. 2015 Jun;135(6):1469-1471. doi: 10.1038/jid.2015.56.
UV radiation is among the most prevalent stressors in humans and diurnal rodents, exerting direct and indirect DNA damage, free-radical production, and interaction with specific chromophores that affects numerous biological processes. In addition to its panoply of effects, UVB (290-320 nm) radiation can specifically affect various local neuroendocrine activities by stimulating the expression of corticotropin-releasing hormone (CRH), urocortin, proopiomelanocortin (POMC), and POMC-derived peptides. Although very little is known about the interplay between the central hypothalamic-pituitary-adrenal (HPA) axis and the skin HPA axis analog, in the current issue Skobowiat and Slominski propose a novel mechanism by which exposure to UVB activates a local HPA axis in skin, which in turn activates the central HPA axis, with the requirement of a functional pituitary gland. This is the first evidence of the local HPA axis in skin contributing to the central neuroendocrine response. This raises intriguing possibilities regarding how local production of cortisol and other HPA axis molecules in skin influence overall systemic levels of cortisol and help regulate local and central HPA axes in the context of homeostasis, skin injury, and inflammatory skin disorders.
紫外线辐射是人类和昼行性啮齿动物最常见的应激源之一，它会直接和间接造成 DNA 损伤、自由基产生，并与特定的生色团相互作用，从而影响许多生物过程。除了其广泛的影响外，UVB（290-320nm）辐射还可以通过刺激促肾上腺皮质激素释放激素（CRH）、尿皮质素、前阿黑皮素原（POMC）和 POMC 衍生肽的表达，特异性地影响各种局部神经内分泌活动。尽管人们对中枢下丘脑-垂体-肾上腺（HPA）轴和皮肤 HPA 轴类似物之间的相互作用知之甚少，但在本期 Skobowiat 和 Slominski 提出了一个新的机制，即暴露于 UVB 会激活皮肤中的局部 HPA 轴，进而激活中枢 HPA 轴，而这需要一个功能正常的垂体。这是皮肤局部 HPA 轴有助于中枢神经内分泌反应的第一个证据。这就提出了一个有趣的可能性，即皮肤中皮质醇和其他 HPA 轴分子的局部产生如何影响皮质醇的整体系统水平，并有助于在稳态、皮肤损伤和炎症性皮肤疾病的背景下调节局部和中枢 HPA 轴。
