Differential long-term stimulation of type I versus type III collagen after infrared irradiation.
BACKGROUND
The dermis is composed primarily of type I (soft) and type III (rigid scar-like) collagen. Collagen degradation is considered the primary cause of skin aging. Studies have proved the efficacy of infrared irradiation on collagen stimulation but have not investigated the differential long-term effects of infrared irradiation on type I and type III collagen.


OBJECTIVE
To determine differential long-term stimulation of type I and type III collagen after infrared (1,100-1,800 nm) irradiation.


METHODS
In vivo rat tissue was irradiated using the infrared device. Histology samples were analyzed for type I and III collagen stimulation, visual changes from baseline, and treatment safety up to 90 days post-treatment.


RESULTS
Infrared irradiation provided long-term stimulation of type I collagen and temporary stimulation of type III collagen. Treatment also created long-term smoothing of the epidermis, with no observed complications.


CONCLUSIONS
Infrared irradiation provides safe, consistent, long-term stimulation of type I collagen but only short-term stimulation in the more rigid type III collagen. This is preferential for cosmetic patients looking for improvement in laxity and wrinkles while seeking smoother, more youthful skin.
Tanaka
Yohei
Y
Department of Plastic and Reconstructive Surgery, School of Medicine, Shinshu University, Matsumoto, Japan. info@clinicatanaka.jp
Matsuo
Kiyoshi
K
Yuzuriha
Shunsuke
S
Shinohara
Hiroshi
H
D000818:Animals; D024042:Collagen Type I / Q000096:biosynthesis*; D024061:Collagen Type III / Q000096:biosynthesis*; D007259:Infrared Rays; D008297:Male; D023421:Models, Animal; D051381:Rats; D017208:Rats, Wistar; D012867:Skin / Q000473:pathology / Q000528:radiation effects*
D024042:Collagen Type I; D024061:Collagen Type III