Institute of Allergology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Allergology and Immunology, Berlin, Germany.
Skin Pharmacol Physiol. 2022;35(5):266-277. doi: 10.1159/000526228. Epub 2022 Jul 29.
Skin microbiome and skin physiology are important indicators of the epidermal homeostasis status. Stress models can reveal pathological conditions and modulating effects. Here we investigated the cutaneous microbiome in relation to skin physiology after mild tape stripping (TS) without treatment compared to two cosmetic leave-on lotions (pH 5.5 vs. pH 9.3) in 25 healthy volunteers.
The microbiome was analyzed by 16S-rRNA-gene amplicon sequencing and put in relation to the following skin physiology parameter: epidermal barrier function (TEWA-Meter TM300), stratum corneum hydration (Corneometer CM 825), surface pH (pH-Meter), and skin erythema (Mexameter).
TS reduced the alpha diversity with a recovery over 7 days without treatment. Both lotions significantly accelerated the recovery of the alpha diversity already after 2 days with a slightly higher rate for the acidic lotion. After TS, the relative abundance of Proteobacteria was increased, whereas Actinobacteria were reduced. The relative abundances of typical skin-associated genera were reduced after TS. Taxa compositions returned to normal levels after 7 days in all treatment groups. An accelerated normalization could be observed with both lotions already after 2 days. A significant difference in skin pH was observed on day 2 and day 7 with an increased pH for the alkaline lotion. Both lotions induced an increase in stratum corneum hydration.
The study proved the suitability of an experimental stress model in the assessment of skin surface microbiome in relation to skin physiology. Stratum corneum hydration increased significantly with both lotions already at day 2. Microbiome parameters (alpha diversity, mean relative taxa, abundance of selected genera) normalized over 2-7 days. The following mechanisms could be responsible for the accelerated normalization of the microbiome: (a) optimized hydration during the recovery phase, (b) the composition of the lotion, (c) the induced repair mechanism. Thus, the formulation has a positive effect on the stratum corneum hydration and subsequently on cutaneous microbiome and skin physiology. Furthermore, this eventually has implications on the modulation of exogenous stress-induced epidermal alterations.
皮肤微生物组和皮肤生理学是表皮动态平衡状态的重要指标。应激模型可以揭示病理条件和调节作用。在这里，我们研究了 25 名健康志愿者在未经治疗的情况下进行轻度胶带剥离（TS）后，与两种美容留置液（pH5.5 与 pH9.3）相关的皮肤微生物组与皮肤生理学的关系。
通过 16S-rRNA 基因扩增子测序分析微生物组，并将其与以下皮肤生理学参数相关联：表皮屏障功能（TEWA-MeterTM300）、角质层水分（CorneometerCM825）、表面 pH（pH-Meter）和皮肤红斑（Mexameter）。
TS 降低了 alpha 多样性，未经治疗可在 7 天内恢复。两种洗液均能显著加速 alpha 多样性的恢复，酸性洗液的恢复速度略高。TS 后，变形菌门的相对丰度增加，而放线菌门的相对丰度减少。TS 后，典型皮肤相关属的相对丰度降低。所有治疗组在 7 天内，分类群组成均恢复正常水平。在 2 天内，两种洗液均可加速正常化。在第 2 天和第 7 天观察到皮肤 pH 值有显著差异，碱性洗液的 pH 值升高。两种洗液均能增加角质层水分。
该研究证明了实验性应激模型在评估皮肤表面微生物组与皮肤生理学的相关性方面的适用性。两种洗液在第 2 天就显著增加了角质层水分。微生物组参数（alpha 多样性、平均相对丰度、选定属的丰度）在 2-7 天内恢复正常。以下机制可能负责微生物组的加速正常化：（a）在恢复阶段优化水合作用，（b）洗液的组成，（c）诱导的修复机制。因此，配方对角质层水合作用具有积极影响，继而对皮肤微生物组和皮肤生理学产生积极影响。此外，这最终对调节外源性应激诱导的表皮改变具有影响。
