Type I collagen production stimulation of water-filtered near-infrared shown through gene expression changes in a 3-dimensional human epidermal tissue model



Background: Water-filtered broad-spectrum near-infrared treatment can provide safe, consistent, and long-term effects for skin rejuvenation, as our previous clinical, histological, and biochemical investigations showed. However, there are few studies that examined changes in gene expression induced. The objective of this study was to investigate changes in gene expression in a 3-dimensional reconstructed human tissue culture exposed to water-filtered broad-spectrum near-infrared irradiation.
Methods: Near-infrared device emits broad spectrum 1000-1800 nm near-infrared together with a water-filter that excludes wavelengths 1400-1500 nm (Titan; Cutera, Brisbane, CA, USA) was used. Cells were exposed to 5 or 10 rounds of near-infrared irradiation at 10 J ⁄cm2. DNA microarray and quantitative real-time PCR analysis was used to assess gene expression levels in a 3-dimensional reconstructed epidermal model composed of normal human epidermal cells exposed to water-filtered broad-spectrum near-infrared irradiation.
Results: A DNA microarray with over 50,700 different probes showed 22 genes that were up- or down-regulated by at least 2-fold after irradiation relative to the control group. Quantitative real-time PCR revealed that the genes which regulates collagen expression was significantly up-regulated compared with controls.
Conclusions: This study provides an objective assessment of gene expression changes induced by water-filtered broad-spectrum near-infrared, and demonstrates its ability to stimulate type I collagen production, which is beneficial for skin rejuvenation applications.


Dr. Yohei Tanaka

Clinica Tanaka Plastic and Reconstructive Surgery and Anti-aging Center

As one of the leading Plastic Surgeons in Japan, Dr. Tanaka brings with him years of experience and a wealth of knowledge in the fields of Plastic and Reconstructive Surgery, anti-aging, and photobiology. He also possesses a deep understanding of and a well-established knowledge about energy based devices. As well as being the Founder of International Photobiological Society, he is also a member of many Japanese and international institutions and societies. Dr. Tanaka has published over 40 peer-reviewed papers in English on topics ranging from plastic and reconstructive surgery to cancer research in a number of prestigious international journals. Through intensive photobiological research, Dr. Tanaka discovered the various biological effects of water-filtered broad-spectrum near-infrared (1000-1800 nm together with a water-filter that excludes wavelengths 1400-1500 nm) including anti-cancer effects.