title: Short-range ultraviolet irradiation with LED device effectively increases serum levels of 25(OH)D.
abstract: Impairment of the activities of daily living (ADL) by osteoporosis is an important concern in developed countries with a super-aging population. Vitamin D, which is a crucial molecule in bone metabolism and mainly produced endogenously with ultraviolet (UV) light exposure, is known to be insufficient in the elderly population. We used an UV Light-Emitting Diode (UV-LED) instrument generating a narrow-range wavelength to analyze the efficacy of endogenous vitamin D production. The primary purpose of this study was to examine the effects of UV irradiation at various narrow-range wavelengths using UV-LED on vitamin D supplementation. The second one was to clarify the short-term effects of UV irradiation on bone morphology in mice. Vitamin D-starved C57BL/6 female mice (n=7 per group) were UV-irradiated (268nm, 282nm, 290nm, 305nm, and 316nm) with 1kJ/m2twice a week for 4weeks. UV irradiation using UV-LED had significant effects on increasing serum 25(OH)D levels in all wavelength groups (P<0.001, all groups) as compared to a control group. Among irradiated groups, wavelength of 316nm had a less marked effect on 25(OH)D production compared with other wavelengths at 1week of UV irradiation (P<0.05). Levels of 1,25(OH)2D were significantly increased after 4weeks irradiation with UV-B or UV-C irradiation (P<0.05). mRNA levels of vitamin D 25-hydroxylase were increased with UV-B or UV-C irradiation (268nm-305nm), significantly. Micro-CT examination revealed that short-term (4weeks) UV-irradiation did not induce morphological change of mice in any group. This study provides essential information that narrow-range UV irradiation with LED can increase the endogenous production of vitamin D, and mRNA levels of the responsible enzyme. Although bone morphology was not altered by short-term UV irradiation in this study, an increase of serum vitamin D might improve bone morphology with long-term irradiation.
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya City 466-8550, Japan. Electronic address: daigood0301@yahoo.co.jp.
authors.forename: Daigo
authors.initials: D
authors.lastname: Morita
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya City 466-8550, Japan. Electronic address: ynishida@med.nagoya-u.ac.jp.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nishida
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya City 466-8550, Japan. Electronic address: rdggd215@yahoo.co.jp.
authors.forename: Yoshitoshi
authors.initials: Y
authors.lastname: Higuchi
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya City 466-8550, Japan. Electronic address: taiseki@med.nagoya-u.ac.jp.
authors.forename: Taisuke
authors.initials: T
authors.lastname: Seki
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya City 466-8550, Japan. Electronic address: k-ikuta@med.nagoya-u.ac.jp.
authors.forename: Kunihiro
authors.initials: K
authors.lastname: Ikuta
authors.affiliation: Development Department, NIKKISO GIKEN Co., Ltd., 4-20-3, Ebisu, Shibuya-ku, Tokyo 150-6022, Japan. Electronic address: hideki.asano@nikkiso.co.jp.
authors.forename: Hideki
authors.initials: H
authors.lastname: Asano
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya City 466-8550, Japan. Electronic address: n-ishi@med.nagoya-u.ac.jp.
authors.forename: Naoki
authors.initials: N
authors.lastname: Ishiguro
mesh_terms: D000818:Animals; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D014466:Ultraviolet Rays; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D055114:X-Ray Microtomography
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: Bone morphology; Light emitting diode; Osteoporosis; Ultraviolet; Vitamin D