The Role of Periostin in Aging

The matricellular protein periostin contributes to proper collagen function and is downregulated during skin aging.
Egbert M1, Ruetze M2, Sattler M1, Wenck H1, Gallinat S1, Lucius R3, Weise JM4.
J Dermatol Sci. 2014 Jan;73(1):40-8. doi: 10.1016/j.jdermsci.2013.08.010. Epub 2013 Sep 3.

Skin aging can be seen:

• on the epidermis by changes in texture and color.
• in the dermis by inducing wrinkles and sagging skin.
• We will focus here on dermal aging.

The dermis is mostly responsible for the volume of the skin and during aging there are the following changes:

• decrease in the quantity of hyaluronic acid which acts to retain the water in the dermis. This is the basis for “filler” injections.
• alterations in the skeleton of the dermis (or extracellular matrix)
• These changes cannot always be compensated by “fillers” but paralysis/ relaxation of underlying muscles can help the extracellular matrix retain its function.

The following article describes how Periostin is important in the maintenance of functional collagen:

• Periostin is an extracellular matrix protein (EMP) which is present in collagen-rich tissues.
• Periostin influences collagen fibrillogenesis in fibroblasts likely by promoting the lateral association of single collagen fibrils.
• Contrarily to most other EMP proteins, it is present all the time, not just during embryogenesis or wound healing
• Through different methods: TaqMan, Real-time PCR, UV irradiation, knockdown experiments, immunostaining, electron microscopy, collagen degradation assay and collagen crosslink analysis…

The authors show that :

• Periostin expression is highest in the papillary dermis and that it is downregulated in intrinsic (natural) and extrinsic (UV light for example) aging.
• knockdown of periostin in fibroblasts  results in increased collagen fibril diameter and aberrant collagen structure.

Comment: Periostin appears to play an important role in the tensile strength of the dermis, and thus the firmness of youthful skin. Enhancing the presence of this protein either by enhancing its expression by fibroblasts or supplying it extrinsically to the tissues might be an interesting way to support this data.

Contributors

Dr Christophe Hsu – dermatologist. Geneva, Switzerland