Skincare For Menopause

Collagen is the most abundant structural protein in the human body (accounting for approximately 30% of total proteins). It is composed of specific amino acid chains that wind into triple helix structures to form extremely resistant fibers. Collagen is diverse, and 28 types of human collagen have been identified in the entire body to date.^[1]

^[1] Ricard-Blum S. The collagen family. Cold Spring Harb Perspect Biol. 2011 Jan 1;3(1):a004978.

It ensures the cohesion, elasticity, and regeneration of all connective tissues. It is essential for the health of bones, cartilage, tendons, and ligaments. In the skin, collagen is vital for maintaining structure and mechanical properties;^[2] it forms a kind of scaffold that maintains the firmness and structure of the dermis. L'Oréal Research & Innovation has highlighted 16 types in the skin that can be classified into 4 collagen families according to their location and role: junctional, pillar, initiator, and linking.

^[2] Diegelmann RF. Analysis of collagen synthesis. Methods Mol Med. 2003; 78:349-58.

Among these 16 collagens present in the skin, there is a specific type that plays a central role in the life cycle of the hair follicle: collagen XVII (COL17). This type of collagen has a crucial anchoring function that is essential for maintaining the structural resilience of the skin and its overall homeostasis.^[3][4] In young, healthy hair follicles, COL17 is abundant. However, with age, its expression decreases. The loss of COL17 destabilizes the Hair Follicle Stem Cell (HFSC) niche, triggering a cascade of events that leads to progressive follicle miniaturization—a clinical characteristic of hair thinning.^[5][6]

^[3] Natsuga, K. (2019). "Life before and after blistering: The role of collagen XVII in epidermal physiology." Experimental Dermatology, 28(10), 1135-1141.
^[4] Xiang, Y., et al. (2022). "Reduced expression of collagen 17A1 in naturally aged, photoaged, and UV-irradiated human skin in vivo: potential links to epidermal aging." Journal of Cellular Communication and Signaling, 16(3), 421-432.
^[5] Matsumura, H. (2016). "Hair follicle aging is driven by transepidermal elimination of stem cells via COL17A1 proteolysis." Science 351(6273): aad4395.
^[6] Xiang, Y., et al. (2022). "Reduced expression of collagen 17A1 in naturally aged, photoaged, and UV-irradiated human skin in vivo: potential links to epidermal aging." Journal of Cellular Communication and Signaling, 16(3), 421-432.