Kao discovers that SPARC is involved in the production of multiple types of collagen

 For many years, Kao has focused on collagen, which is important for skin firmness, and has been conducting research on the relationship between collagen and proteins existing in the body called SPARC (Secreted protein acidic and rich incysteine), and SPARC has multiple types of collagen. For the first time in the world, it was revealed that it plays a role as a control tower that works on production at the same time.

There are 9 types of collagen in the skin, and it plays an important role for the firmness of the skin by repeating synthesis and decomposition to keep it healthy. Type 1 collagen occupies about 70% of the dermis and forms the foundation of the skin in a thick fibrous morphology.

On the other hand, type 4 and type 7 collagen are the main constituents of the basement membrane that separates the dermis and epidermis of the skin, and type 4 collagen occupies about 50% of the biomolecules that make up the basement membrane and is in the form of a sheet. It forms the skeleton of the basement membrane, and type 7 collagen has the function of connecting the basement membrane and the dermis. Both collagens play an important role in the formation of the basement membrane, which has the function of maintaining healthy skin by controlling the supply of nutrients from the dermis to the epidermis.

SPARC is a protein that has various functions such as promoting cell proliferation, differentiation, and migration. It is made in the epidermis and dermis in the skin, and is known to increase when wounds heal.

The Kao Group is conducting research on the belief that SPARC plays an important role in skin collagen, and in 2012, it was found that SPARC promotes the production of type 1 collagen and reported.

This time, focusing on the action of SPARC on type 4 and type 7 collagen, when SPARC was added to cultured dermal fibroblasts and epidermal cells, respectively, the production of type 4 and type 7 collagen increased in both cells. It was confirmed.

Furthermore, when SPARC was added to the three-dimensional skin model, it was also found that type 4 and type 7 collagen accumulated in the basement membrane and promoted the formation of the basement membrane. From these findings, it became clear for the first time in the world that SPARC plays a role as a control tower that works on the production of multiple types of collagen at the same time.

It has been reported that the structure of the basement membrane deteriorates in aged skin, which affects firmness and wrinkles.

This time, in order to investigate the relationship between SPARC and photoaging, we compared the part of the same person who was aged by ultraviolet rays (photoaging) and the part that was not exposed to much ultraviolet rays, and found that SPARC decreased in the former part. It turned out that there was. From this, it is considered that the production of SPARC is reduced in photoaged skin, the ability to produce type 4 and type 7 collagen is weakened, and it is involved in the structural deterioration of the basement membrane.

We will continue to elucidate the relationship between SPARC and collagen and apply this knowledge to cosmetics development. The results of these studies were presented at the 53rd Annual Meeting of the Connective Tissue Society of Japan.