Holding it together: uncovering the Diversity of collagen in the skin

Collagen is the most abundant protein in the human body and is often referred to as the glue that holds the body together. Its importance is most evident in the skin.

It is no wonder that the word collagen is derived from the Greek kolla, meaning glue,1 because of its incredible ability to hold the body together. In this article, we will explore the importance of collagen and its function within the dermis layer of the skin, the main types of collagens found within the skin, and how they each contribute to the overall health and appearance of the skin.

Collagen is the primary component of the extracellular matrix

In the skin, collagen is present as long fibres within the extracellular matrix of the dermis, the thickest layer of skin.2,3 Incredibly, excluding water, collagen accounts for a massive 75% of the skin by weight.3

The primary function of collagen in the extracellular matrix is to maintain the structural integrity of the skin, giving it mechanical stability, elasticity, and strength.2

Collagen is an essential protein that forms the structural foundation of the skin, specifically within the extracellular matrix of the skin’s dermis layer.2,3

The collagen-rich extracellular matrix plays an indispensable role in providing an environment in which the cells of the skin can thrive; an environment where cells can build and repair skin components to maintain structural integrity and function.2-4 Importantly, collagen fibres within the extracellular matrix provide the skin with tensile strength, durability, and elasticity, which together allow the skin to bounce back.3

The role of collagen in ageing skin

Changes to the skin are often a telltale sign of ageing, with fine lines and thinning skin occurring naturally as we age, alongside stress-induced changes, like deep wrinkles and loss of elasticity.3

In young and youthful skin, collagen fibres are abundant, tightly packed, and well-organised.3 However, in contrast, older and ageing skin contains collagen fibres that are often fragmented and distributed unevenly, resulting in the telltale signs of ageing.3

Both wrinkles and loss of elasticity caused by the ageing process have been linked to progressive thinning of the skin. Thinning of the skin includes a decrease in the amount of extracellular matrix, which is itself driven by a reduction of Collagen.3

Aging Skin

The collagen-rich extracellular matrix can also break down during ageing, becoming disparate and unevenly distributed. This process is driven by an overall decline in the amount of collagen in the skin, caused by both decreased production of collagen as well as increased breakdown of collagen.3

Overall, the reduction of collagen in ageing skin can cause the skin to undergo significant changes, contributing to the emergence of ageing features such as wrinkles and reduced skin elasticity.3

Young V Aged Skin

Collagen in the skin

Collagen is distinguished by its unique and intricate triple helix arrangement, which is the key to its distinctive and versatile properties. In the skin, collagen’s main properties influence firmness, strength, and elasticity.2

Amazingly, there are at least 28 distinct collagen types found all over the body, but the skin primarily consists of only three types: Collagen types 1, 3 and 5.5

Collagen in the skin has three distinct types, each with their own unique role

Dna Artwork
Type 1Type 3Type 5
80 – 90%8 – 12%Less than 5%
Structural support and strengthCreating and organising type 1 collagenRegulating the size and organisation of collagen
Firmness and durabilityElasticityBalancing firmness and elasticity

Type 1 collagen

Type 1 collagen is the most abundant form of collagen in the skin, comprising 80% to 90% of the total collagen in the skin.3 It is densely packed, forming compact fibres that provide structural support and strength to the skin.6

Type 1 is the most significant a pivotal role in maintaining the skin’s firmness and durability.6

As we age, the production of Type I collagen declines, leading to a loss of skin elasticity and the appearance of wrinkles.4

Type 3 collagen

Type 3 collagen makes up 8% to 12% of the total collagen in the skin and is often found alongside Type 1 collagen, which collectively contributes to almost 95% of the skin’s structure.3,5

Type 3 collagen plays a crucial role in the formation of Type 1 collagen by organising the densely packed Type 1 collagen fibres.2,5

Type 3 collagen is important for skin elasticity.2

Type 5 collagen

Although Type 5 collagen makes up less than 5% of the total collagen in the skin,3 it has a vital role in regulating the organisation and size of collagen fibres in the skin.7

Specifically, Type 5 collagen provides structural support. It regulates the diameter or thickness of collagen fibres which in turn influences the organisation of fibres. In doing so, Type 5 collagen is crucial for influencing the balance between firmness and elasticity of the skin.5,7

Understanding the different types of collagen and their roles may prove useful when adopting a skincare regime. Collagen underpins the structural integrity of the skin, with the various types of collagen working in unison to balance strength, firmness, and elasticity.2-4 Supporting collagen production in the skin could hold promising potential in maintaining youthful and radiant skin as we age.5

References

  1. “Collagen.” Oxford Advanced Learner’s Dictionary. Accessed [Date accessed: 27 March 2024]. Available from: https://www.oxfordlearnersdictionaries.com/definition/english/collagen?q=collagen
  2. Wang H. Polymers (Basel). 2023 Oct 5;15(19):3999.
  3. Shin JW, et al. Int J Mol Sci. 2019 Apr 29;20(9):2126.
  4. Campos LD, et al. Heliyon. 2023 Mar 28;9(4):e14961.
  5. Liu H, et al. Photodermatol Photoimmunol Photomed. 2024 Jan;40(1):e12931.
  6. Pu SY, et al. Nutrients. 2023 Apr 26;15(9):2080.
  7. Wenstrup RJ, et al. J Biol Chem. 2004 Dec 17;279(51):53331-7.