Infrared and Broadband Light for Skin Aging

Studies in model organisms suggest that aged cells can be functionally rejuvenated, but whether this concept applies to human skin is unclear. Recently, we applied 3'-end sequencing for expression quantification ("3-seq") to discover the gene expression program associated with human photoaging and intrinsic skin aging (collectively termed "skin aging"), and the impact of broadband light (BBL) treatment. We found significant changes in 2,265 coding and noncoding RNAs, of which 1,293 that became "rejuvenated" after BBL treatment, whereby they became more similar to their expression level in youthful skin. Rejuvenated genes (RGs) included several known key regulators of organismal longevity and their proximal long noncoding RNAs. Hence, BBL treatment can restore gene expression pattern of photo-aged and intrinsically aged human skin to resemble young skin.

However, the duration of these effects and the potential to augment these effects through increases in particular wavelengths of light have not been explored. The Sciton SkinTyte (800-1800nm) is the ideal technology to examine these questions, since this device has been used in the clinical setting to reduce cheek and submental laxity (Gold, 2010). It incorporates the broadband light technology with an emphasis on 590 nm filter to achieve these clinical results.

This study will be conducted in accord with Declaration of Helsinki principles. After Institutional Review Board approval and informed consent is obtained, six female participants over the age of 55 years will undergo BBLST treatments to the left forearm. Inclusion criteria included Fitzpatrick skin type II or III, and a global assessment of forearm skin aging consistent with moderate or severe forearm skin aging (modified validated instrument from McKenzie et al., 2011) for treated participants. Treatments will be performed on the Sciton Joule Platform using BBL in Skintyte mode with 590ST filter. On a separate part of the arm that is clearly marked, Skintyte alone will be applied. Untreated areas will also be marked. All markings will be photographed. The same investigator will perform the treatments at 4-week intervals for a total of 3 treatments. At each treatment session, two or more passes were performed. Four weeks after the third BBL treatment, 4 mm skin biopsies will performed by Keys punch technique from the BBLST treated, ST treated and adjacent untreated skin. These specimens will be bisected and placed into either RNAlater (Ambion Cat# AM7022) or formalin solution for with H&E, von Giesen or PAS staining.

Inclusion criteria

• 1. Female 2. Age 55 years or older (total 6) 3. Fitzpatrick skin type 2-3 4. Photo-aging at least moderate on the extensor forearms

Exclusion criteria

• 1. Unable to understand and sign informed consent form 2. Unable to comply with study procedures 3. Pregnant or lactating 4. Prior treatment to forearms including topical retinoid, laser treatment, photodynamic treatment, prescription topical agents x 1 month 5. Active skin conditions that precluding treatment including zoster, blistering skin disease, psoriasis, atopic dermatitis, abnormal scarring, skin cancer in the area of study treatment 6. Currently on hormone based therapy (both systemic and topical)