title: The role of mast cells in non-ablative laser resurfacing with 1,320 nm neodymium:yttrium-aluminium-garnet laser.
abstract: The aim of this study was to investigate the role of mast cells in mechanisms of collagen remodelling induced by non-ablative laser treatment. The dorsal skin of Kunming (KM) mice was exposed to 1,320 nm neodymium-yttrium-aluminium garnet (Nd:YAG) laser weekly for four consecutive weeks. Biopsies were taken 1 h after irradiation and 1 day, 7 days, 14 days, 30 days and 60 days after the first treatment. Skin samples were studied for mast cells, fibroblasts, and type I and III collagen, by toluidine blue, haematoxylin-eosin (HE) and immunohistochemical staining, respectively. The total number of mast cells in the skin of experimental group was significantly greater than that in the control at 1 h, 1 day, 21 days and 60 days after the first treatment (P < 0.05, respectively). At any of the time points studied, the number of degranulated mast cells in the experimental group was significantly higher than in the control (P < 0.01, P < 0.01, P < 0.05, P < 0.01, P < 0.05, P < 0.05, respectively).The number of fibroblasts in the experimental group exhibited a significant increase in comparison with those in control skin at days 7, 21, 30 and 60 after irradiation (P < 0.05, P < 0.01, P < 0.01, P < 0.05, respectively). The amount of type I collagen was significantly higher than in the control from day 21 to day 60 (P < 0.05, P < 0.01, P < 0.01, respectively), and type III collagen showed a marked increase between day 7 and day 60, compared with the control (P < 0.01, P < 0.05, P < 0.01, P < 0.01, respectively). There was a significant positive correlation between the number of fibroblasts and granulated mast cells (r = 0.549, P < 0.01). The amount of type I and III collagen also showed significant positive correlations with the number of degranulated mast cells (r = 0.555, P < 0.01 and r = 0.579, P < 0.01, respectively). The results suggested that dermal mast cells might be involved in the inflammatory response, fibroblast proliferation and collagen remodelling induced by non-ablative laser treatment.
authors: Institute for Laser Medicine and Bio-photonics, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China.
authors: Yingbin
authors: Y
authors: Shang
authors: Zhan
authors: Z
authors: Wang
authors: Ying
authors: Y
authors: Pang
authors: Peng
authors: P
authors: Xi
authors: Qiushi
authors: Q
authors: Ren
mesh_terms: D000818:Animals; D049109:Cell Proliferation / Q000528:radiation effects; D024042:Collagen Type I / Q000378:metabolism; D024061:Collagen Type III / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D028022:Low-Level Light Therapy; D008407:Mast Cells / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D051379:Mice; D015595:Skin Aging / Q000473:pathology / Q000502:physiology / Q000528:radiation effects*; D014945:Wound Healing / Q000528:radiation effects
chemical_list: D024042:Collagen Type I; D024061:Collagen Type III