Collagen is the most abundant protein in the human body; accounting for approximately 25% of the body’s protein mass. As a major component of connective tissue, it can be found in the skin, muscles and tendons. In the last few years, this protein has gained a lot of attention in the media due to the plethora of scientific studies revealing its ability to support gut integrity, ageing skin, bone mass and joint health.
What is important to realise, however, is that there are many different types of collagen – each with their own biological function. To date, over 29 different types of collagen have been identified;1 with types I, II and III being the most prevalent within the human body. For this reason, it is important to choose the most appropriate type of collagen depending on needs.
This article will discuss the basics of collagen synthesis, with a focus on collagen type II; the form of collagen which makes up 70-95% of the cartilage in joints.
How does collagen work in the body?
As a type of protein, collagen is made up of amino acids such as glycine, lysine and proline. Specialised cells called fibroblasts play a key role in collagen synthesis. They work by incorporating these amino acids into complex strands in order to create the basic collagen molecule. This basic molecule then undergoes further binding, cross-linking and folding depending on the final type of collagen being produced. It is important to note that vitamin C is an essential co-factor in this process and so low levels of this vitamin can impair collagen production.
As mentioned, 29 types of collagen have been identified to date, with 80-90% of them belonging to types I, II and III.
|Type I||Dermis, tendon, ligaments and bone|
|Type II||Cartilage, vitreous body (in the eye), nucleus pulposus (inner core of vertebral disc)|
|Type III||Skin, vessel wall, reticular fibres of most tissues (lungs, liver, spleen etc.)|
Function of collagen type II
Hyaline (or articular) cartilage is a firm, gel-like substance which covers the bones. Its primary function is to provide cushioning and reduce friction between bones as they slide over or against each other. Collagen type II is a major component of the extracellular matrix of this hyaline cartilage and its synthesis and catabolism is regulated by chondrocytes (cells found in cartilage connective tissue).
The hyaline cartilage within the body has a very specific composition, with its predominant matrix elements consisting of:
- Collagen type II fibres: the main structural component of cartilage, providing structure, firmness and resistance to compression – this accounts for 60% of cartilage.
- Glycosaminoglycans (GAGs): mainly consist of two building blocks – aggrecan (a large proteoglycan containing chondroitin sulphate) and hyaluronic acid, both essential components for maintaining a cushioned and lubricated joint environment, allowing for easy joint movement – this accounts for approximately 40% of the cartilage.
Sources of collagen
Collagen can be found in animal proteins like eggs, chicken, meat and bone broth; with the body naturally making collagen from certain amino acids and nutrients including vitamin A, vitamin C and copper. The body’s ability to produce collagen naturally declines with age by as much as a 1% reduction annually.2,3 As such, supplementary collagen has been investigated as a possible way to mitigate the effects of this decline.
Collagen supplements: what’s the difference?
There are three key types of collagen available as supplements: gelatin, hydrolysed collagen and undenatured collagen. When collagen is boiled down for a significant amount of time (such as in bone broth), gelatin is produced. When this is further broken down or ‘pre-digested’ into its amino acid peptides, hydrolysed collagen is created. On the other hand, undenatured collagen, often referred to as UC-II is not broken down.
|Grade||Structure||Solubility||Absorption & Digestibility||Applications|
Native (undenatured) collagen
Large triple helix chains of amino acids
Medical materials, collagen casings, supplements
Soluble in warm liquids
Gelatin desserts, confectionary, functional foods
Soluble in warm and cold liquids
Dietary supplements, functional foods
Much of the research which has been carried out regarding collagen type II has used either undenatured (UC-II) or hydrolysed (Peptan IIm) collagen. However, as these are essentially two different products, they can be difficult to compare:
As it is not broken down, this undenatured collagen is insoluble, with low bioavailability within the body. As such, its primary mode of action is based on immune modulation.4,5 It has been shown that UC-II can induce an immune response signalling the activation of collagen production, but does not provide the specific building blocks required for cartilage creation. As only small amounts of this collagen can be absorbed, a low dose between 20-40mg is recommended.
A form of hydrolysed collagen type II which has been specifically formulated with joint health in mind. It has been matrixed with chondroitin sulphate and hyaluronic acid, making it identical to the composition of cartilage in humans. As a natural source of collagen, it can stimulate the synthesis of collagen within the body, while also providing the building blocks necessary for joint support. The recommended dose for Peptan IIm is 1-3g/daily.
Peptan IIm collagen Type II and Joint Health – what does the research say?
Maintaining sufficient levels of collagen is essential for the maintenance of healthy and flexible joints. Studies have shown the following effects of collagen type II consumption on joint health:
- Improved overall joint health: Peptan treatment resulted in a 32% decrease in joint pain and a 44% improvement in stiffness among women with osteoarthritis (classification: 0-III).6 A statistically significant reduction in the WOMAC score (international standard method for assessing joint health) was also observed
- Improved knee-joint function: Peptan treatment resulted in a 7% increase in the Lysholm score; a scale linked to improved knee movement in everyday activities.6 In a 24-week clinical trial, improved joint health and a reduced risk of joint deterioration in athletes was observed following supplementation with hydrolysed collagen.7 Furthermore, statistically significant improvements in activity related joint pain versus control were also observed8
- Chondrocyte (cartilage cell) stimulation: Hydrolysed collagen type II treatment stimulated chondrocyte excretion of type II collagen9
- Protection from degeneration: In a model for post-traumatic osteoarthritis, Peptan supplementation provided protection to cartilage from degeneration, as well as promotion of lubrication through the stimulation of proteoglycan synthesis in chrondrocytes.10 Similar findings were found in a model for obesity-associated osteoarthritis10
- Anti-inflammatory effect: Peptan supplementation showed an anti-inflammatory effect in the knee joint10
- Improved recovery: Following supplementation with hydrolysed type II collagen and glycosaminoglycans, blood markers associated with muscular stress, including creatine kinase, lactate dehydrogenase and c-reactive protein all showed improvements compared with control11
- Collagen is the most abundant protein in the human body. As a major component of connective tissue, it can be found in the skin, muscles and tendons etc.
- To date, over 29 different types of collagen have been identified, with types I, II and III accounting for 80-90% of collagen in the body.
- Specialised cells called fibroblasts play a key role in collagen synthesis in the body. They work by incorporating amino acids such as proline, lysine and glycine into complex strands in order to create the basic collagen molecule. This basic molecule then undergoes further binding, cross-linking and folding depending on the final type of collagen being produced. Vitamin A, vitamin C and copper are important for collagen production.
- The body’s ability to synthesise collagen declines with age.
- Collagen is naturally found in animal proteins such as eggs, chicken, meat and bone broth.
- Collagen type II is primarily used to support joint health as it makes up 70-95% of the cartilage in joints. It is a major component of the extracellular matrix of hyaline cartilage; a firm, gel-like substance which covers the bones. The primary function of cartilage is to provide cushioning and reduce friction between bones as they slide over or against each other. Collagen accounts for 60% of this, while other matrix elements such as aggrecan (a large proteoglycan containing chondroitin sulphate) and hyaluronic acid are also present.
- There are three key types of collagen available as supplements: gelatin, hydrolysed collagen and undenatured collagen.
- Undenatured collagen is not broken down and therefore is insoluble and has poor bioavailability in the body. Its primary mode of action is based on immune modulation.
- Hydrolysed collagen has been broken down or ‘pre-digested’ into its amino peptides which allow it to be fully soluble and highly bioavailable. A special form of hydrolysed collagen type II called Peptan IIm has been matrixed with chondroitin sulphate and hyaluronic acid, making it identical to the composition of human cartilage.
- Several studies looking into the effect of Peptan IIm on joints has demonstrated improvements in overall joint health, knee-joint function, stimulation of chrondrocytes (cartilage cells), protection from degeneration, improved recovery and an anti-inflammatory capacity.
CytoProtect® Joints is formulated using Peptan® IIm powder, a hydrolysed matrix of type II collagen and glycoaminoglycans (chondroitin sulphate and hyaluronic acid).
CoQ10 Multi – comprehensive multivitamin and mineral, additionally containing CoQ10
Vitamin A – vegan-friendly product, containing 5,000IU of retinol palmitate.
Cherry C – 200 mg vitamin C from acerola cherry plus naturally occurring bioflavonoids.
- Saxena T et al (2014) ‘Proteins and Poly(Amino Acids)’ Nat Synth Biomed Polym, pp. 43-65.
- Varani J et al (2006) ‘Decreased Collagen Production in Chronologically Aged Skin : Roles of Age-Dependent Alteration in Fibroblast Function and Defective Mechanical Stimulation’ Am J Pathol, 168(6), pp. 1861.
- Nyman JS et al (2006) ‘Age-related effect on the concentration of collagen crosslinks in human osteonal and interstitial bone tissue.’ Bone, 39(6), pp. 1210-1217.
- Barnett ML et al (1998) ‘Treatment of rheumatoid arthritis with oral type II collagen: Results of a multicenter, double-blind, placebo-controlled trial.’ Arthritis Rheum, 41(2), pp. 290-297.
- Min S-Y et al (2004) ‘Induction of IL-10-producing CD4+CD25+ T cells in animal model of collagen-induced arthritis by oral administration of type II collagen.’ Arthritis Res Ther, 6(3), pp. 213-9.
- Jiang I-X et al (2014) ‘Collagen Peptides Improve Knee Osteoarthritis in Elderly Women A 6-Month Randomized, Double-Blind, Placebo-Controlled Study’ Agro Food Industry High Tech, 25 (2), pp. 19-23.
- Clark KL et al (2008) ’24-Week study on the use of collagen hydrolysate as a dietary supplement in athletes with activity-related joint pain.’ Curr Med Res Opin, 24(5), pp. 1485-1496.
- Zdzieblik D et al (2017) ‘Improvement of activity-related knee joint discomfort following supplementation of specific collagen peptides.’ Appl Physiol Nutr Metab, 42(6), pp. 588-595.
- Oesser S and Seifert J (2003) ‘Stimulation of type II collagen biosynthesis and secretion in bovine chondrocytes cultured with degraded collagen.’ Cell Tissue Res, 311(3), pp. 393-399.
- Rousselot (2011) Rousselot Unpublished Data, retrieved from: https://www.peptan.com/about-peptan/downloads/peptan-joint-health-in-vitro-study-whitepaper/.
- Lopez HL et al (2014) ‘Effects of BioCell Collagen® on connective tissue protection and functional recovery from exercise in healthy adults: a pilot study.’ J Int Soc Sports Nutr, 11, pp. 48.