December 07, 2016

SFU researchers have identified the crucial first stage of how collagen self-assembles into fibrils. The study, funded by the Natural Sciences and Engineering Research Council, was published today in Biophysical Journal.

Collagen is a fundamental structural protein in the human body that makes up 30 per cent of our skin, bone and other connective tissues. 

Understanding at what stage collagen assembly takes place will further guide the ability to manipulate this process so it can be controlled for advantageous purposes, such as tissue regeneration or the design of new biocompatible materials. Lead investigator Nancy Forde, a professor in the Department of Physics at SFU, explains the research further.

What are fibrils?

Fibrils are rope-like structures with threads of individual collagen proteins. They are found throughout the human body performing critical mechanical and biochemical functions. They are also widely used in bioengineering to make new materials for tissue engineering and for medicine.

What does collagen do?

One of collagen’s remarkable features is its ability to send biological signals to direct cellular development and undergo processes of renewal. Throughout their biological lifespan, our collagen-containing connective tissues undergo processes of renewal, where collagen fibrils are broken down and rebuilt by cells living in their housing.

How can collagen renewal be harmful to one’s health?

Collagen renewal balances fibril production and demolition. Problems can arise if this balance is upset. For example, excess collagen production can lead to fibrosis (permanent scarring), which can have severe medical implications. Excess collagen removal is implicated in metastasis of cancer and in many age-related connective tissue diseases. 

Meanwhile chemical changes in collagen lead to mechanical changes in the protein structure that manifest as, for example, wrinkling skin, brittle bones and arthritis. In wound healing, collagen can be produced and assembled too quickly. This can lead to significant health challenges such as fibrosis, which results in permanent scarring and underlying tissue damage.

What did your research find?

It has long been known that the ability of collagens to adhere to each other and rapidly grow into thick fibrils was suppressed when the short ends of collagens (called telopeptides) were removed.  We found that this telopeptide-dependent stickiness was apparent even before collagen started assembling into fibrils, much earlier than had been previously known.  This provides guidance in the search for a "dial" to control the rate at which collagen assembles into fibrils.

 Can your research eventually impact these conditions?

We hope so. Other projects in our lab focus on how genetic mutations and chemical modifications associated with aging alter the mechanical properties of collagen.  We are also looking at how these affect collagen’s ability to be remodelled.