Low energy irradiation of narrow-range UV-LED prevents osteosarcopenia associated with vitamin D deficiency in senescence-accelerated mouse prone 6

摘要

Deficiency of vitamin D is an important cause of osteosarcopenia. The purpose of this study is to examine the effects of low energy narrow-range UV-LED on osteosarcopenia in animal models of senescence-accelerated mouse prone 6 (SAMP6). Preliminary experiments specified the minimum irradiance intensity and dose efficacy for vitamin D production (316?nm, 0.16?mW/cm2, 1,000?J/m2). we set a total of 4 groups (n?=?8 per group); vitamin D-repletion without UV irradiation (Vit.D+UV?), vitamin D-repletion with UV irradiation (Vit.D+UV?+), vitamin D-deficiency without UV irradiation, (Vit.D?UV?), and vitamin D-deficiency with UV irradiation (Vit.D?UV?+). Serum levels of 25(OH)D at 28 and 36?weeks of age were increased in Vit.D?UV+ group as compared with Vit.D?UV??group. Trabecular bone mineral density on micro-CT was higher in Vit.D?UV+ group than in Vit.D?UV? group at 36?weeks of age. In the histological assay, fewer osteoclasts were observed in Vit.D?UV+ group than in Vit.D?UV? group. Grip strength and muscle mass were higher in Vit.D?UV+ group than in Vit.D?UV? group at 36?weeks of age. Signs of severe damage induced by UV irradiation was not found in skin histology. Low energy narrow-range UV irradiation may improve osteosarcopenia associated with vitamin D deficiency in SAMP6.