微生态护肤——皮肤屏障修复的新高度

浙江喜美恩健康管理有限公司    邵华

众所周知，皮肤是人体最大的器官，也是人体防御外部伤害的最外层屏障。起初，人们认为皮肤仅是一层被动的、无意识的机械防护屏障，但随着科学研究的深入，人们逐渐发现皮肤是能感知危险信号，并对入侵病原体采取适当防御措施的具有主动活性的器官。在2018年Cell Press出版的《Trends in Immunology》杂志中，发表了一篇关于皮肤屏障和皮肤免疫力的文章《Cutaneous Barriers and Skin Immunity: Differentiating A Connected Network》。文章着重论述了皮肤四层屏障（微生物屏障、化学屏障、物理屏障和免疫屏障）的不同功能特点、他们之间的互相联系、以及由此组成的完整屏障体系和强大防御体系。

The skin is the outermost barrier of the organism that ensures protection from external harm. Lately, our view of the skin has evolved from an inert mechanical barrier to an active organ that can sense danger signals and mount perfectly adapted defense measures in response to invading pathogens. This Review highlights the different levels of the cutaneous barrier (the microbiome, chemical, physical, and immune barriers), their characteristics, and functional, highly interconnected network of cells and mediators that allow balanced defense measures to protect the body and maintain barrier integrity^[1].

其实关于皮肤微生物群与皮肤屏障、皮肤疾病的关系，在近几年国内杂志中已相继有不少报道。皮肤微生物群是指定植在皮肤上的所有微生物，包括细菌、病毒、真菌等。许多常见皮肤病的发生都与皮肤微生物相关，如脂溢性皮炎、痤疮、特应性皮炎、银屑病等^[2]。相关研究显示，皮肤常驻菌具有占位保护作用，有层次有序地定植在皮肤上，犹如一层生物屏障，使致病菌及外籍菌无法立足于皮表。同时其可分解皮脂甘油三酯为脂肪酸，形成乳化皮脂膜，既对自身及表皮角质形成细胞具有营养作用，又可防止皮表水分蒸发^[3]。皮肤微生态系统在保护皮肤的健康状态中起到了不可忽视的作用。建立健康的表皮生物膜、激活人体抗菌肽和引入益生元等方式，是强化皮肤屏障的新手段。如个人护理品中使用的低聚果糖（FOS）和低聚半乳糖（GOS）就是著名的益生元，可以被皮肤有益菌使用，而不被致病菌利用^[4]。以乳杆菌与双歧杆菌为代表的益生菌，作为新一代皮肤病抗菌治疗的生物制剂，已经具备替代抗生素疗法的潜力。微生物制剂疗法逐渐成为研究者们关注的焦点^[5]。

喜美恩公司作为一家专注于护肤品研发和销售的公司，长期以来一直致力于问题肌肤的研究和解决，尤其在敏感肌的舒缓和屏障修复方面，联合国际专业研发实验室，秉承前沿护肤理念，甄选全球高品质原料，在修复系列产品中引入微生态护肤的理念，采用菊粉（FOS）和α-葡聚糖寡糖（GOS）等益生元成分，以及乳酸杆菌/豆浆发酵产物滤液、芽孢杆菌发酵产物等益生素成分，强化微生物屏障的保护和修复。

在传统概念里，皮肤屏障主要指的是皮脂膜加角质层的物理屏障。而《Cutaneous Barriers and Skin Immunity: Differentiating A Connected Network》一文中专门论述了皮肤的四层不同屏障及其主要功能。“微生物屏障”是皮肤屏障的最外层。皮肤表层的微生物群落组成了这层活跃、有效的“第一反应屏障”以应对外界环境状况。皮肤细胞、皮肤免疫系统和皮肤菌群间的三重联系实现了微生物屏障的功能性。“化学屏障”包含着维持皮肤表面酸性pH值的因子和“天然保湿因子（NMF）”。“物理屏障”主要包括角质层、紧密连接体系（即常说的“砖墙结构”）以及它们的调节功能（调节表皮水分流失TEWL）。“免疫屏障”代表了皮肤屏障的最后部分，表皮和真皮中有着各种免疫细胞。常驻免疫细胞进一步促进屏障修复和维持肌肤平衡状态。免疫屏障的细胞分布在全部皮肤上，因此，免疫屏障与其他皮肤屏障又高度相关联。

The microbiome barrier is the outermost layer of the cutaneous barriers. The microbial communities on the skin also constitute a living and ideal first response barrier to environmental factors. They act as a border post and transmit external signals to the functional immune network of the skin. The outcome of this threefold crosstalk between skin cells, the skin immune system, and skin microbiota determines the functionality of the macrobiotic barrier.

Commonly, the ‘chemical barrier’ comprises factors that contribute to the acidic surface pH and compounds that together comprise the ‘natural moisturizing factor’ (NMF) .

Important parts of the physical barrier are the SC and the system of tight junctions (TJ) and their regulation. The contents of those granules fill the acellular space of the SC, which is often referred to as ‘mortar between bricks’. These intercellular lipids provide a tight and effective barrier that also regulates trans epidermal water loss (TEWL) .

The immune barrier represents the final part of the cutaneous barrier and comprises a variety of resident immune cells populating the epidermis and dermis. Resident immune cells further contribute to barrier repair and homeostasis. Given that cells of the immune barrier are distributed all over the skin, this barrier is highly interconnected with other levels of the cutaneous barrier^[1].

同时，文章还进一步强调：不同程度的屏障受损都会导致微生物生态失衡。因此，微生物屏障是皮肤屏障密不可分的一部分。皮肤屏障层次的多样性、可塑性和灵活性，以及巨大的再生潜力，一定程度上都依赖于功能健全的微生物屏障。通过微生物成分的调节来精准管理屏障功能是一种前瞻性的方法，甚至还可以干预疾病的发展。

Barrier disruption at different levels results in microbial dysbiosis. Therefore, microbiome barrier is an integrated part of the cutaneous barriers. The diversity of the components of the cutaneous barriers, their plasticity and flexibility, together with their enormous potential to regenerate, partly rely on a well-functioning microbiome barrier. Precise orchestration of cutaneous barrier functioning through regulation of the microbial composition is a promising approach to use to intervene with disease development^[1].

随着越来越多皮肤疾病的发生，不同程度导致屏障功能的破坏，而屏障功能的破坏又进一步加重这些皮肤病甚至成为新问题产生的诱因。皮肤屏障的作用不言而喻，修复屏障也成为了皮肤病治疗环节中的重要一环。在各类皮肤疾病的《诊疗指南》、《专家共识》中，也都强调修复屏障的重要性，强调合理使用护肤品的必要性。而屏障修复需要满足两个条件：一个是组织的自愈能力，一个是微生物屏障的修复。虽然皮肤的自愈过程已广为人知，但微生物屏障的修复却还需要进一步的深入研究。

To restore barrier integrity, two prerequisites have to be fulfilled: initiation of tissue healing and restoration of the microbiome barrier. Whereas wound-healing responses are largely well understood, the restoration of the microbiome barrier is not and, therefore, is currently under intensive investigation^[1].

喜美恩明星修复系列，在结合前沿理念，注重微生态护肤的基础上，与“屏障修复明星”神经酰胺、天然保湿因子（NMF）以及免疫调节修复的β-葡聚糖等成分，做到全方位、多层次修复屏障，真正从源头维护皮肤健康！

参   考   文   献

[1] Stefanie Eyerich. et al. Cutaneous Barriers and Skin Immunity: Differentiating A Connected Network [J]. Trends in Immunology, 2018,39(4):315-327. dol:10.1016/j.it.2018.02.004

[2] 闫慧敏,姜薇.人类皮肤微生物群和皮肤疾病[J].中国皮肤性病学杂志,2015,29(12):1292-1294

[3] 方红.皮肤微生态的研究进展[J].中华皮肤科杂志,2014,47(1):1-3

[4] 孙琦.皮肤微生物组对强化皮肤屏障的作用[J].生物化工,2017,3(6):116-120

[5] 马晨,张和平.皮肤微生物与益生菌在皮肤疾病诊疗中的应用[J].食品科学,2016,37(9):269-273