Eşrefoğlu Mukaddes, Seyhan Muammer, Gül Mehmet, Parlakpinar Hakan, Batçioğlu Kadir, Uyumlu Burçin
Department of Embryology and Histology, Faculty of Medicine, Inonu University, Malatya, Turkey.
J Pineal Res. 2005 Oct;39(3):231-7. doi: 10.1111/j.1600-079X.2005.00235.x.
It is generally agreed that one of the major contributors to skin aging is reactive oxygen species. As organisms reach advanced age, free radical generation increases and the activity of tissue antioxidant enzyme system decreases. Melatonin is an antioxidant and free radical scavenger. The present study was first aimed to determine the morphometric and biochemical changes caused by long-term pinealectomy in order to investigate the role of melatonin as skin architecture. Secondly, the effect of exogenous melatonin administration on these changes was determined. Rats were pinealectomized or sham operated (control) for 6 months. Half of the pinealectomized rats were treated with 4 mg/kg melatonin during the last month of the experiment. Pinealectomy resulted in important morphometric and biochemical changes in the back, abdominal and thoracic skin. The thickness of epidermis and dermis and the number of dermal papillae and hair follicles were reduced. Melatonin administration to pinealectomized rats significantly improved these alterations in all body areas (P < 0.005). On the contrary, in pinealectomized rats the levels of antioxidant enzymes, catalase and glutathione peroxidase were decreased. Melatonin restored the levels of these enzymes. The pinealectomy-induced increases in lipid peroxidation in the abdominal and thoracic skin were significantly reduced by melatonin treatment (P < 0.005 and 0.01 respectively). These results suggest that melatonin is highly efficient anti-aging factor and, as melatonin levels decrease with age, melatonin treatment may reduce age-related skin changes.
人们普遍认为，活性氧是皮肤衰老的主要促成因素之一。随着生物体步入老年，自由基生成增加，组织抗氧化酶系统的活性降低。褪黑素是一种抗氧化剂和自由基清除剂。本研究首先旨在确定长期松果体切除所引起的形态学和生化变化，以研究褪黑素在皮肤结构中的作用。其次，确定外源性给予褪黑素对这些变化的影响。将大鼠进行松果体切除或假手术（对照）6个月。在实验的最后一个月，对一半的松果体切除大鼠给予4mg/kg的褪黑素。松果体切除导致背部、腹部和胸部皮肤出现重要的形态学和生化变化。表皮和真皮厚度以及真皮乳头和毛囊数量减少。给松果体切除的大鼠施用褪黑素显著改善了所有身体部位的这些改变（P<0.005）。相反，在松果体切除的大鼠中，抗氧化酶、过氧化氢酶和谷胱甘肽过氧化物酶的水平降低。褪黑素恢复了这些酶的水平。褪黑素处理显著降低了松果体切除诱导的腹部和胸部皮肤脂质过氧化增加（分别为P<0.005和0.01）。这些结果表明，褪黑素是一种高效的抗衰老因子，并且随着年龄增长褪黑素水平下降，褪黑素治疗可能会减少与年龄相关的皮肤变化。
