Collagen: The Skin Structural Protein

Collagen is a major structural protein in the skin. It plays a key role in providing the structural scaffolding for cells, tissues, and organs. If it weren't for collagen, the body would literally fall apart. Collagen also gives the skin its strength and durability and is responsible for the smooth, plump appearance of young, healthy skin. Understanding the structure and function of collagen will help you better know how to maintain a healthy, youthful appearance.

What Is Collagen?
Collagen is the body's major structural protein composed of three protein chains wound together in a tight triple helix. This unique structure gives collagen a greater tensile strength than steel. Approximately 33 percent of the protein in the body is collagen. This protein supports tissues and organs and connects these structures to bones. In fact, bones are also composed of collagen combined with certain minerals such as calcium and phosphorus.

Collagen plays a key role in providing the structural scaffolding surrounding cells that helps to support cell shape and differentiation, similar to how steel rods reinforce a concrete block. The mesh-like collagen network binds cells together and provides the supportive framework or environment in which cells develop and function, and tissues and bones heal.

Collagen and Beauty
Collagen makes up 75 percent of our skin; thus, the smooth, plump appearance of young, healthy skin is due in large part to the presence of healthy collagen levels. Because of this, beauty seekers around the globe search for new ways to boost collagen levels and repair past collagen damage—some go so far as to inject collagen proteins into the skin to plump wrinkles and add volume to the lips. The breakdown of healthy collagen and the decline in collagen production leads to the development of unwanted wrinkles and the appearance of aged skin.

Collagen Synthesis
Collagen is created by fibroblasts, which are specialized skin cells located in the dermis. Fibroblasts also produce other skin structural proteins such as elastin (a protein which gives the skin its ability to snap back) and glucosaminoglycans (GAGs). GAGs make up the ground substance that keeps the dermis hydrated. In order to signal or turn on the production of skin structural proteins, fibroblast cells have specially shaped receptors on their outside membranes that act as binding sites to which signal molecules with a matching shape can fit. When the receptors are bound by the correct combination of signal molecules (called fibroblast growth factors, or FGFs), the fibroblast begins the production of collagen.

Fibroblasts initially produce short collagen subunits called procollagen. These are transported out of the fibroblast cells and later join together to form the complete collagen molecule. Vitamin C acts as a cofactor during many steps of the process. Without sufficient levels of vitamin C, collagen formation is disrupted. This disruption leads to a variety of disorders such as scurvy—a disease where the body cannot produce collagen and, as a result, essentially falls apart as these support structures (collagen) deteriorate.

Collagen synthesis occurs continuously throughout our lives to repair and replace damaged collagen tissue or build new cellular structures. The degradation and recycling of old or damaged collagen is a healthy, natural process used to create protein fragments needed to build new cellular structures, such as in the healing process. With age, collagen levels drop off due to a decrease in production and an increase in degradation.

Protecting Current Collagen Levels and Preventing Future Collagen Degradation
The best way to maintain a healthy, youthful looking appearance is to protect the healthy collagen you currently have and to prevent future collagen degradation. There are two main ways to do this: 1) avoid UVA and UVB radiation and 2) prevent free radical damage.

Exposure to ultraviolet (UVA and UVB) radiation emanating from the sun is the most prolific contributor to premature skin aging, accounting for an estimated 90 percent of the signs associated with aging skin. UV exposure must be limited and individuals should wear a daily sunscreen to protect healthy collagen. Many skin care companies understand this need and incorporate sunscreens into their daytime moisturizers.

The second preventive step in protecting existing and future collagen levels is supplementation with both oral and topical antioxidants. As antioxidants fight free radicals from UV light, ozone, pollution, cigarette smoke, and internal metabolic processes, they prevent the degradation of existing collagen fibers and protect the healthy function of fibroblast cells.

Promoting the Synthesis of New Collagen
There are many ways to promote the synthesis of new, healthy collagen. First, you can provide the skin with a reserve of vitamin C. As a necessary cofactor in collagen synthesis, vitamin C is proven to increase the production of collagen. One study showed that extended exposure of human connective-tissue cells to vitamin C stimulated an eight-fold increase in the synthesis of collagen (Murad et al., 1981).

Another way to promote the synthesis of collagen is to use chemical exfoliants, such as alphahydroxy and polyhydroxy acids, which break down the bonds between cells of the stratum corneum and slough away dead skin. Consistent exfoliation stimulates cell renewal. Chemical exfoliation has also been shown to increase dermal thickness. Scientists attribute this dermal thickening to the synthesis of glycosaminoglycans and collagen within the dermis.

A third way to promote collagen synthesis is to supplement with collagen stimulating peptides. Fibroblasts are naturally stimulated to begin the synthesis of collagen when specific combinations of peptide signal molecules (fibroblast growth factors) bind to receptor sites on the fibroblast membrane. These signal molecules can be supplemented with topically and help boost collagen production. Some skin care companies are including these peptide fragments in their treatment products.

Because collagen gives the skin its strength, durability, and smooth, plump appearance, it's important to protect and promote collagen growth. Taking good care of your skin means taking care of your collagen.

Zoe Diana Draelos
M.D., F.A.A.D.

Dr. Draelos worked extensively with Nu Skin to create the Nu Skin® Profiler and conducted clinical research on the use of Tru Face™ Revealing Gel with Polishing Peel,™ as well as studies on Tru Face™ Line Corrector and Tru Face™ IdealEyes.® She serves on the board of directors for the American Academy of Dermatology and has a research interest in cosmetics, toiletries, and biologically active skin medications. Dr. Draelos is a practicing, board certified dermatologist in High Point, North Carolina, and a clinical associate professor of dermatology at Wake Forest University School of Medicine.