Nutrition in wound healing: investigation of the molecular mechanisms, a narrative review.

Nutrition can be outlined in terms of epigenetic signals influencing each of the wound healing steps (haemostasis, inflammatory, proliferative and remodelling phase). Specific nutrients, such as amino acids, minerals, vitamins, natural compounds and herbal extracts, target DNA-regulating transcription factors, cytokines, extracellular matrix proteins and glycosaminoglycan, and are specifically involved in the wound healing process. This review focuses on experimental in vivo and clinical evidence of dietary supplements administration in pressure ulcers. A good nutritional status is, for example, fundamental to the haemostasis phase of skin wounds. In the inflammatory phase, vitamin A enhances cytokine release, bromelain and amino acids prevent prolonged inflammatory events, while vitamin C enhances neutrophil migration and lymphocyte activation. In the proliferative phase, vitamin C and Centella asiatica are required for collagen synthesis. Glucosamine enhances hyaluronic acid production, vitamin A promotes epithelial cell differentiation, zinc is required for DNA and protein synthesis and cell division, and Aloe vera supports granulation tissue generation. Finally, in the remodelling phase, amino acids and proteins play a key role in wound scar stabilisation.