Modulation of tropoelastin and fibrillin-1 by infrared radiation in human skin in vivo.
BACKGROUND
The heat produced by exposure to infrared radiation (IR) has been demonstrated to modulate the expression of tropoelastin and fibrillin-1, the two main components of elastic fibers in human skin in vivo. However, the effect of IR range of radiations on tropoelastin and fibrillin-1 expression has not been thoroughly investigated.


METHODS
Eighteen volunteers were enrolled in this study involving three trials. Time-dependent, dose-dependent and cumulative effects of IR were investigated, respectively. Tropoelastin and fibrillin-1 expression was measured by immunohistochemical staining on skin biopsy samples from volunteers. In addition, we also measured tropoelastin mRNA expression by a real-time RT-polymerase chain reaction.


RESULTS
A single dose of IR (2 minimal heating dose) induced a time-dependent increase in tropoelastin expression at the protein level. An inverse correlation was found between the alterations of tropoelastin and fibrillin-1. Furthermore, IR was found to increase tropoelastin expression in a dose-dependent manner at both the mRNA and the protein level. Repeated low doses of IR increased tropoelastin expression and decreased fibrillin-1 expression at the protein level in the dermis. Meanwhile, the number of both fibers along the dermal-epidermal junction was increased.


CONCLUSIONS
IR can alter the expression of tropoelastin and fibrillin-1, which may result in abnormal elastic fiber formation.
Chen
Zhou
Z
Department of Dermatology, Peking University People's Hospital, Beijing, China.
Zhuo
Feng-Lin
FL
Zhang
Shang-Jun
SJ
Tian
Yan
Y
Tian
Shan
S
Zhang
Jian-Zhong
JZ
D001483:Base Sequence; D017931:DNA Primers; D004307:Dose-Response Relationship, Radiation; D000071838:Fibrillin-1; D000071837:Fibrillins; D006801:Humans; D007150:Immunohistochemistry; D007259:Infrared Rays; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012867:Skin / Q000378:metabolism / Q000528:radiation effects*; D014333:Tropoelastin / Q000235:genetics / Q000378:metabolism*; D054392:Adipokines
D017931:DNA Primers; D000071838:Fibrillin-1; D000071837:Fibrillins; D008840:Microfilament Proteins; D012333:RNA, Messenger; D014333:Tropoelastin; C000605722:FBN1 protein, human; D054392:Adipokines