Background. Stem cells from adipose tissue (ADSCs) and platelet-rich plasma (PRP) are innovative modalities that arise due to their regenerative potential. Objective. The aim of this study was to characterize possible histological changes induced by PRP and ADSC therapies in photoaged skin. Methods. A prospective randomized study involving 20 healthy individuals, showing skin aging. They underwent two therapeutic protocols (protocol 1: PRP; protocol 2: ADSCs). Biopsies were obtained before and after treatment (4 months). Results. PRP protocol showed unwanted changes in the reticular dermis, mainly due to the deposition of a horizontal layer of collagen (fibrosis) and elastic fibers tightly linked. Structural analyses revealed infiltration of mononuclear cells and depot of fibrotic material in the reticular dermis. The ADSC protocol leads to neoelastogenesis with increase of tropoelastin and fibrillin. There was an improvement of solar elastosis inducing an increment of macrophage polarization and matrix proteinases. These last effects are probably related to the increase of elastinolysis and the remodeling of the dermis. Conclusions. The PRP promoted an inflammatory process with an increase of reticular dermis thickness with a fibrotic aspect. On the other hand, ADSC therapy is a promising modality with an important antiaging effect on photoaged human skin.

中文翻译：

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PRP 和 ADSC 的光老化皮肤治疗：一项比较研究。

背景。来自脂肪组织 (ADSC) 和富含血小板的血浆 (PRP) 的干细胞是由于其再生潜力而出现的创新模式。客观。本研究的目的是描述 PRP 和 ADSC 疗法在光老化皮肤中可能引起的组织学变化。方法。一项涉及 20 名健康个体的前瞻性随机研究，显示皮肤老化。他们接受了两种治疗方案（方案 1：PRP；方案 2：ADSC）。在治疗前后（4个月）进行活检。结果. PRP 协议显示网状真皮发生了不必要的变化，主要是由于胶原蛋白（纤维化）和紧密连接的弹性纤维的水平层沉积。结构分析揭示了网状真皮中单核细胞的浸润和纤维化物质的储存。ADSC 方案导致新弹性体生成，原弹性蛋白和原纤维蛋白增加。日光弹性组织有改善，导致巨噬细胞极化和基质蛋白酶增加。这些最后的影响可能与弹性蛋白溶解的增加和真皮的重塑有关。结论. PRP 促进炎症过程，增加网状真皮厚度并伴有纤维化。另一方面，ADSC 疗法是一种很有前途的方式，对光老化的人体皮肤具有重要的抗衰老作用。