Exploring the role of a nonablative laser (1320 nm cooltouch laser) in skin photorejuvenation

Background: Nonablative laser has been used for the treatment and prevention of skin aging for many years. Although the mechanism has not been elucidated, histological evaluation showed that the dermal fibroblasts and its collagen production should be the main target for this rejuvenation. In order to determine the effects of a 1320 nm nonablative laser on the human dermal fibroblasts, the two main secretion factors, basic fibroblast growth factor (bFGF) and transforming growth factor β1(TGF‐β1), in vitro were detected. Methods: The human dermal fibroblasts were cultured and irradiated with a 1320 nm laser at the dose of 15, 20, and 24 J/cm2 respectively. The number of fibroblasts was counted and the levels of bFGF and TGF‐β1 were detected by enzyme‐linked immunosorbent assay at the time points of 0, 24, 48, and 72 h after irradiation. Results: The results showed that both the number of fibroblasts and the secretion of bFGF increased after the irradiation at the dose of 20 and 24 J/cm2 (P