Institute for Advanced Study of Mathematical Sciences, Meiji University, Nakano-ku, Tokyo, 164-8525, Japan.
Shiseido Global Innovation Center, Nishi-ku, Yokohama, 220-0011, Japan.
Exp Dermatol. 2022 Apr;31(4):459-474. doi: 10.1111/exd.14494. Epub 2021 Nov 12.
It was long considered that the role of epidermal keratinocytes is solely to construct a water-impermeable protective membrane, the stratum corneum, at the uppermost layer of the skin. However, in the last two decades, it has been found that keratinocytes contain multiple sensory systems that detect environmental changes, including mechanical stimuli, sound, visible radiation, electric fields, magnetic fields, temperature and chemical stimuli, and also a variety of receptor molecules associated with olfactory or taste sensation. Moreover, neurotransmitters and their receptors that play crucial roles in the brain are functionally expressed in keratinocytes. Recent studies have demonstrated that excitation of keratinocytes can induce sensory perception in the brain. Here, we review the sensory and information processing capabilities of keratinocytes. We discuss the possibility that epidermal keratinocytes might represent the earliest stage in the development of the brain during the evolution of vertebrates.
长期以来，人们一直认为表皮角质形成细胞的作用仅仅是在皮肤的最上层构建一个不透水的保护膜——角质层。然而，在过去的二十年中，人们发现角质形成细胞包含多种感觉系统，可检测环境变化，包括机械刺激、声音、可见光、电场、磁场、温度和化学刺激，以及与嗅觉或味觉相关的各种受体分子。此外，在大脑中起关键作用的神经递质及其受体在角质形成细胞中也有功能性表达。最近的研究表明，角质形成细胞的兴奋可以在大脑中诱导感觉感知。在这里，我们回顾了角质形成细胞的感觉和信息处理能力。我们讨论了这样一种可能性，即表皮角质形成细胞可能代表了在脊椎动物进化过程中大脑发育的最早阶段。
