LED device effectively increases serum levels of 25(OH)D3 in osteoporosis rats

Osteoporosis is a bone disease associated with aging. As the population ages, osteoporosis has become a significant public health problem that threaten life quality of most countries in the world. Adequate vitamin D is able to improve intestinal calcium absorption, promote bone mineralization, maintain muscle strength, enhance balancing ability, and reduce fall risks, whichplays a vital role in bone metabolism. Moreover, vitamin D is mainly produced by ultraviolet (UV) light. The serum levels of 25(OH)D3 is the tools for estimating of the osteoporosis.It is known that vitamin D deficiency is ubiquitous in the elderly population, hence, we adopted UV light-emitting diode (UV-LED) instruments to generate narrow-range wavelengths of UV and determined its capability for producing vitamin D. The osteoporosis SD rats are our research subjects. The study was to investigate the effects of UV-LEDs of different power densities on vitamin D production. There are 4 groups：0.1, 0.2, 0.4, 0.8mW/cm2 and the rats (n = 6 per group) were irradiated with different power densities twice a week for a total of 8 weeks. The results showed that serum 25(OH)D3 levels rapidly increased in all irradiated groups compared with those in the control group (P < 0.001 in all groups), and 25(OH)D3 level of the rats in groups of both 0.4 and 0.8 m W/cm2 were able to return to the initial level at the fourth week after irradiation, besides, the group of 0.4 mW/ W/cm2 can achieve and maintain the highest25(OH)D3 level and so as the group of 0.8 m W/cm2 as the continuing irradiation. We demonstrate that the proper irradiation density of UV-LED irradiation can increase the production of vitamin D in rats and does not adversely affect the skin of rats.