The 5 pillars of skin ageing

As skin ages naturally, a cascade of events is put in motion. These events modify the skin’s histological and molecular composition, affecting its conditions of moisturization, luminosity, presence of wrinkles or its elasticity, among other factors.

Based on the scientific evidence, we believe there are five essential pillars that significantly contribute to maintaining and regulating healthy skin.

With age, skin loses its elasticity due to deficiencies in the composition of collagen and elastin, proteins that are key to keeping skin young and moisturized. Collagen is a protein that is released into the space between the cells that make up skin. It interacts with other proteins present in this space to form the extracellular matrix. Collagen binds together to form fibrillar structures, thus acting as a scaffold for skin cells. Collagen is responsible for giving skin its elasticity and smoothness. Its structure is like a “safety net” for our cells. Collagen is naturally synthesized and degraded in the skin. But as the skin ages, this balance breaks down, and the natural production of collagen becomes slower than its degradation. This collagen deficiency translates into signs of cutaneous ageing such as: less smoothness, greater flaccidity, more dehydration or dryness and appearance of visible wrinkles. A marked effect on the depth and size of wrinkles is directly related with the concentration of collagen in the skin.

In histological terms, skin is made up of two layers of cells: the epidermis and the dermis. The area where these two layers are joined is called the dermal-epidermal junction. The exchange of nutrients and metabolites (as well as waste products) takes place here. Throughout life, skin cells divide to replace those that have aged. It must be remembered that epithelial tissue is in permanent regeneration. Therefore, the cell division rate in this tissue is among the highest in the entire body. Our genetic material, organized into chromosomes inside the cells, has a repetitive DNA structure that protects its tips, which are called telomeres. The length of telomeres is directly related with our cells’ and skin’s stage of ageing. Over the progressive cell divisions of epithelial cells, the length of the telomeres is compromised. As they are shortened, they stop protecting the tips of our chromosomes, leading to the degeneration and death of skin cells, which trigger inflammatory processes and oxidative stress in epithelial tissue.

In the process of ageing, either due to external factors such as UV radiation, pollution or chemical agents, or internal physiological factors caused by cell death or inflammatory processes, the skin’s oxidation level is altered, leading to the accumulation of cells from the immune system and free radicals. These are molecules capable of oxidizing proteins or other molecules, altering their natural, healthy function. 
Inflamed skin with a high content of free radicals does not have a healthy appearance. It may show spots, lack consistency or luminosity.
This is why antioxidant substances have such beneficial effects on skin, just like all products capable of controlling inflammatory processes that occur due to the death of epithelial cells. The death of skin cells generates a less healthy appearance and an accumulation of waste products that are detrimental to the maintenance of young and luminous skin.

It has been observed that as cells age, there is an increase in the concentration of beta-galactosidase (b-Gal). B-Gal is an enzyme (a protein with a specific function) whose function is to ferment sugars. An increase in b-Gal is associated with a dysfunction or poor function of cellular lysosomes (organelles containing important enzymes that regulate a number of cellular processes, such as intracellular digestion of matter from inside and outside the cell, nutrients, etc.) and that can be considered the beginning of a degenerative effect on the tissue to which the cell belongs. B-Gal is considered an important senescence marker, and key for the proper physiological function of healthy cells.

As already mentioned, skin is a tissue in constant cellular renewal. The epidermis, its most outer layer, contains four different cell types: keratinocytes, melanocytes, Langerhans cells and Merkel cells. Keratinocytes are the most abundant cells in the epidermis (some 80% of epidermal cells) and are essential to regulate, among other functions, the skin’s permeability. Melanocytes are cells responsible for producing melanin, that are very important for protection against UV radiation. Fibroblasts, the cells responsible for collagen production, are prominent in the dermis, the most internal layer of the skin. The development and differentiation of these cells originate in a group of pluripotent stem cells located in the deepest layers of the skin. As skin ages, the number of stem cells diminishes, leading to a lower regeneration rate of the cells that make up the skin. The non-replacement of dead cells by new cells translates into a marked ageing effect of the skin.