Aims
This study investigated effects of narrow-range ultraviolet irradiation (UVR) by a new UV-LED device on vitamin D supply and changes of bone in senescence-accelerated mouse P6 (SAMP6) with vitamin D deficiency. Main
Methods
We used female SAMP6 mice as a senile osteoporotic model. We set a total of 3 groups (n = 4 per group); D-UVR+ group (vitamin D deficient-dietary and UVR), D- (vitamin D deficient-dietary), and D+ groups (vitamin D contained-dietary). Mice in the D-UVR + group were UV-irradiated (305nm) with 1 kJ/m2 twice a week for 12 weeks from 20 to 32 weeks of age. Serum 25(OH)D, 1,25(OH)2D, and micro-computed tomography (CT) were assessed over time. Mechanical test, and histological assay were performed for femurs removed at 32 weeks of age. Key findings: UVR increased both serum 25(OH)D and 1,25(OH)2D levels at 4 and 8 weeks-UVR in the D-UVR+ group compared with that in the D- group (P < 0.05, respectively). Relative levels of trabecular bone mineral density in micro-CT were higher in the D-UVR+ group than in the D- group at 8 weeks-UVR (P = 0.048). The ultimate load was significantly higher in the D-UVR+ group than in the D- group (P = 0.036). In histological assay, fewer osteoclasts and less immature bone (/mature bone) could be observed in the D-UVR+ group than in the D- group, significantly. Significance: UVR may have possibility to improve bone metabolism associated with vitamin D deficiency in SAMP6 mice.
Significance
UVR may have possibility to improve bone metabolism associated with vitamin D deficiency in SAMP6 mice.