黑素细胞对表皮渗透屏障功能的影响

表皮渗透屏障功能是表皮的主要生理功能之一,深肤色个体较浅肤色个体具有更优越的表皮屏障功能,提示黑素细胞和/或黑素与表皮渗透屏障功能密切相关.有关黑素细胞对角质形成细胞及对表皮渗透屏障功能影响的机制尚不清楚,近几年研究发现,酸性黑素小体进入表皮可能是深肤色者表皮屏障功能增强的细胞基础,表皮pH对增强屏障功能重要性不可忽视,内源性酸化机理可能提供一个促进深肤色个体表皮酸化的新机制.此外,黑素细胞-角质形成细胞的交叉对话及相关信号机制可能在增强表皮渗透屏障功能中起重要作用.

Effects of Melanocytes on Epidermal Permeability Barrier

Human skin acts as the primary barrier between the body and its environment. As one of the major physiological functions of epidermis, the epidermal permeability barrier serve to protect the organism from environmental hazards and to prevent the loss of nutrients, water and i-ons. The dysfunction of epidermal permeability barrier underlies a wide array of skin diseases. It was found that increased pigmentation imparted enhanced barrier function to the epidermis of darkly pig-mented subjects, suggesting that melanocytes and/or melanin might be closely related to epidermal barrier function. The mechanisms by which melanocytes regulate keratinocytes and epidermal barrier function remains unclear. Recent studies suggested that melanin persistence/extrusion into the extra-cellular spaces and enhanced expression of the acidifying enzyme secretory phospholipase A2 f (sPLA2f) might contribute to the pH-dependent acceleration of lipid processing, lamellar bilayer maturation, and enhanced barrier function of pigmented epidermis. Furthermore, the keratinocyte-melanocyte cross-talk and associated-signals might play a critical role in this process.