Antiphotoaging effect of chitooligosaccharides on human dermal fibroblasts

Background/Purpose: In the present study, the effect of 3-5 kDa chitooligosaccharide (COS) on homeostasis between the expression of collagen-degrading matrix metalloproteinases (MMPs) and collagen synthesis was investigated using ultraviolet (UV)-A irradiated dermal fibroblasts. Methods: UV protection imparted by 3-5 kDa COS was measured by examining the UV absorption spectrum. Collagenase MMP secretion was examined using an enzyme-linked immunosorbent assay. The levels of collagenases and collagen synthetic markers were determined by employing the reverse transcriptase-polymerase chain reaction and Western blot analysis. Results: The 3-5 kDa COS not only absorbed UV-A and UV-B light but also inhibited collagenase (MMP-1, MMP-8, and MMP-13) and gelatinase (MMP-2 and MMP-9) MMP expression. The suppression of MMP expression was found to be due to an increase in expression of the tissue inhibitors of MMP (TIMP)-1 and TIMP-2. Treatment with 3-5 kDa COS enhanced collagen synthetic markers such as procollagen, type I, III, and IV collagens in UV-A-irradiated dermal fibroblasts. Furthermore, the effects of 3-5 kDa COS on collagen degradation and collagen synthesis in UV-A irradiated dermal fibroblasts were regulated via the inhibition of activating protein-1 (AP-1) signaling. Conclusion: Our results suggest that 3-5 kDa COS can be used to develop as topical applications for antiphotoaging cosmeceuticals as it enhances collagen synthesis.