Dipeptide-6 is a dipeptide formed through a peptide bond linking proline (Pro) and hydroxyproline (Hyp). Considered one of the primary characteristic peptide fragments produced during the digestion and subsequent breakdown of collagen within the human body, it serves as a near-constant biomarker of collagen metabolism. Hydroxyproline itself is an amino acid unique to collagen; the stability and various forms of biological activity associated with this dipeptide depend heavily on its presence – maintaining at least partial structural integrity of the skin being one such outcome.

Sequence

H-Pro-Hyp-OH

CAS Number

18684-24-7

Molecular Formula

C₁₀H₁₆N₂O₄

Molecular Weight

228.25 g/mol

Research Of Dipeptide-6

Collagen is the primary structural protein found in most connective tissues (skin, bones, cartilage being prime examples). Characteristic repeating sequences (Gly-X-Y, X/Y again typically Pro or Hyp) give these tissues their desired elasticity and all round mechanical strength. Hydroxyproline as mentioned is that defining amino acid, its content a near real time reflection of the body’s current metabolic state regarding collagen.

Hydroxyproline containing peptide segments are the key bioactive parts of any collagen derived peptide – Pro-Hyp and related forms being well documented. Oral administration allows for some level of absorption, entering the bloodstream to at least partially regulate skin fibroblast function.

Dipeptide-6 is a naturally occurring peptide, derived from said collagen. Animal sourced collagen (fish skin, bovine etc.) undergoes both human and industrial digestion/hydrolysis; long chains break down into small peptides, H-Pro-Hyp-OH being one of the more easily detected bioactive end products.

Research into its mechanism is currently pointing towards the anti-aging effects of dipeptide-6 as being directly related to the stimulation of fibroblast proliferation and activity.

Promoting Fibroblast Proliferation and Collagen Synthesis: Fibroblasts are the primary ‘factories’ responsible for synthesizing the skin scaffolding and hydrating components; collagen, elastin, and hyaluronic acid being the most well-documented examples. Their active function significantly declines with age.

Multiple in vitro studies consistently show that Dipeptide-6 effectively activates fibroblast proliferation and subsequent migration. Research specifically points to Dipeptide-6 stimulating this proliferation and growth – mouse and human skin fibroblasts both responding to it.

A chemotactic aspect is also observed, fibroblasts being attracted to move towards certain areas; repair of skin damage and various forms of tissue remodeling depend on this process.

Dipeptide-6 has been shown to significantly enhance hyaluronic acid synthase activity within fibroblasts. Directly related to the above, improved skin hydration (a plumper, near-dewy appearance) results from increased production.

A randomized, double-blind, placebo controlled clinical trial using a high concentration collagen peptide formulation containing Pro-Hyp demonstrated improvements in facial skin hydration, elasticity, wrinkles and roughness metrics over 8 weeks.

Promoting ECM Regeneration and Remodeling: Activating fibroblasts as mentioned above, indirect ECM regeneration is a key outcome. Upregulation of specific ECM proteins (type I collagen being the prime example, along with elastin and fibronectin) at the genetic level has been reported.

Inhibition of Matrix Metalloproteinase-1 (MMP-1) Expression: Oral supplementation of collagen peptides leads to increased plasma levels of Gly-Pro and all related dipeptides; reducing UVB induced MMP-1 is one of the more measurable end points of this pathway.

Dipeptide-6, in all its forms, is a true multi-faceted regulator of skin physiology. Facial aging is only one of many potential benefits of Pro-Hyp or similar dipeptides.