Premature Aging Takes the Heat with Infrared

Infrared A radiation increased levels of the collagen-degrading enzyme MMP-1 and depleted cutaneous antioxidents.

Excessive exposure to sunlight ages skin prematurely. Although researchers have attributed the harm primarily to UVA and UVB radiation, sunlight includes wavelengths outside the UV spectrum. In fact, approximately 30% of all solar energy that reaches the earth’s surface lies within the infrared A (IRA) range (760–1440 nm). To determine whether infrared A contributes to photoaging, investigators exposed 23 volunteers to 360 or 720 J/cm² IRA, levels that can be reached with a few hours of sun exposure in temperate climates.

In approximately 80% of the volunteers, these doses produced 3-fold to 14-fold increases in matrix metalloproteinase-1 (MMP-1), an enzyme that degrades elastin and types I and III collagen. The effect of infrared A on MMP-1…

Reviewing Author

Craig A. Elmets, MD

Disclosures

Consultant / Advisory board Astellas Pharmaceuticals

EquityVaxin

Grant / Research support NIH; NIH/NCI; Veteran’s Administration; Ferndale Laboratories; Kyowa Hakko Kirin Pharma, Inc.

Editorial boards Cancer Prevention Research; Photodermatology, Photoimmunology, & Photomedicine; UpToDate; eMedicine; Journal of Dermatological Sciences; JAMA Dermatology

Leadership positions in professional societies American Academy of Dermatology (Vice Chair, Committee on Science and Research); Photomedicine Society (Board of Directors)