The combination of red and near IR LED lights may significantly induce COL1A1, ELN, collagen and elastin protein formation in both human adult dermal fibroblasts and in human skin explants. Furthermore, it is shown for the first time that red plus near IR lights combination may also induce LOXL1 gene expression and enhance elastic fiber crosslinks, which are necessary for functional elastic fibers to contribute to skin structural support as skin firmness decreased with photo-aging. The mechanism of action (MOA) of red plus near IR lights combination treatment may be through inducing ATP production.

Raman spectra acquired on pigmented, intermediate and unpigmented hair. (a) Dendrogram showing the hierarchical cluster analysis (HCA) of Raman spectra acquired on hair ex vivo. (b) Mean Raman spectra representative of each group previously determined by HCA. (c) Zoom on Raman spectral region (Raman band center : 1,580 cm-1 corresponding to the vibration of the ring νC–C) analyzed to investigate melanin content. (d) Quantification of melanin content in each group. Statistical analyses according to Student’s t test compared to pigmented hair (with ***: p < 0.001)

In this study, the repeated differences in the indoor and outdoor temperature and humidity in South Korea and Southeast Asia during summer have been suggested to lead to skin aging.