Hyaluronic acid: A key molecule in skin aging

TLDR

Skin aging involves intrinsic and extrinsic mechanisms that reduce moisture, and hyaluronic acid—through its water‑retaining capacity and complex regulation—plays a central role in maintaining skin turgor. The study aims to elucidate how hyaluronic acid metabolism varies across skin layers and interacts with other components to enable rational modulation of skin moisture.

Abstract

Skin aging is a multifactorial process consisting of two distinct and independent mechanisms: intrinsic and extrinsic aging. Youthful skin retains its turgor, resilience and pliability, among others, due to its high content of water. Daily external injury, in addition to the normal process of aging, causes loss of moisture. The key molecule involved in skin moisture is hyaluronic acid (HA) that has unique capacity in retaining water. There are multiple sites for the control of HA synthesis, deposition, cell and protein association and degradation, reflecting the complexity of HA metabolism. The enzymes that synthesize or catabolize HA and HA receptors responsible for many of the functions of HA are all multigene families with distinct patterns of tissue expression. Understanding the metabolism of HA in the different layers of the skin and the interactions of HA with other skin components will facilitate the ability to modulate skin moisture in a rational manner.