Sensing the environment

Viac o knihe

The skin, the body's largest organ, serves as a crucial interface with the external environment, detecting and responding to various stressors, including solar radiation. It functions as a peripheral neuroendocrine-immune organ, closely linked to central regulatory systems, aiding in the maintenance of peripheral homeostasis. Epidermal and dermal cells produce and respond to stress neurotransmitters, neuropeptides, and hormones, stimulated by ultraviolet radiation, biological factors, and other agents. Local biologically active products include cytokines, biogenic amines (such as catecholamines, histamine, serotonin), melatonin, acetylcholine, and various neuropeptides and hormones from the pituitary and hypothalamus. The production of these molecules follows a hierarchical organization along classical neuroendocrine axes, including the hypothalamic-pituitary-adrenal axis and others. Disruptions in these axes or their communication can lead to skin and systemic diseases. Additionally, these neuroendocrine networks help limit the effects of harmful environmental agents, preserving local and global homeostasis. Skin-derived factors can activate cutaneous nerve endings to alert the brain or coordinate responses through direct neurotransmission. Rapid communication between epidermal, dermal, and adnexal compartments is also facilitated by neurotransmission, allowing skin cells to regulate both peripheral and global homeostasis eff