Lactate in skin homeostasis: metabolism, skin barrier, and immunomodulation

Lactate is crucial for skin homeostasis, influencing metabolism, the skin barrier, and immune responses. It is produced by skin cells like keratinocytes and hair follicle stem cells and contributes to energy metabolism, protein and lipid synthesis, and cell renewal. Lactate acts as a signaling molecule, modulating inflammation and immune responses, and is involved in post-translational modifications affecting gene expression. It enhances skin barrier proteins, modulates pH, and influences protective functions. In inflammatory skin diseases, lactate promotes anti-inflammatory macrophage polarization and regulates immune cells, offering therapeutic potential. It also plays roles in hair loss, wound healing, and skin aging, with applications in treating alopecia and improving skin smoothness. Elevated lactate levels are linked to skin disorders, making it a target for therapeutic strategies. Further research is needed to optimize its use in skin health.