Vitamin D is a fat-soluble vitamin that has proven to be extremely important for human health. Vitamin D has important functions that regulate calcium and phosphate absorption from the gastrointestinal tract. The regulation of calcium and phosphorus metabolism is extremely important for the maintenance of the structural integrity of the human skeleton, neuromuscular function and a wide variety of metabolic processes. A major source of vitamin D for most children and adults if exposure to sunlight. During sun exposure 7-dehydrocholesterol in the epidermis and dermis absorb solar ultraviolet B radiation with wavelengths of 290-315nm. This results in it being converted to previtamin D. Once formed, the thermodynamically unstable previtamin D is isomerized to vitamin D. Vitamin D is then hydroxylated in the liver and the kidneys to its active form before it can act as a homeostatic regulator of calcium and phosphorus metabolism. There are certain patients who do not respond well to vitamin D supplements because they suffer from fat malabsorption syndromes such as cystic fibrosis, Crohn’s disease and ulcerative colitis. In addition, gastric bypass patients have difficulty in absorbing dietary and supplemental vitamin D. One approach for treating vitamin D deficiency in these patients is to recommend that they be exposed to artificial UVB radiation either from a tanning bed or from a Sperti vitamin D producing lamp. Novel ultraviolet emitting light emitting diodes (LED) have emerged as a promising solution because of their size, efficiency, and ability to use narrow band UV radiation. A LED has been developed to emit narrowband UVB radiation with a peak wavelength of that 295nm.
This thesis provides evidence that this novel UVB-LED is able to cause the photo-conversion of 7-deyhdrocholesterol to previtamin D3 in vitro, using 7-dehydrocholesterol containing borosilicate ampoules as positive controls, as well as produce vitamin D3 in surgically obtained type II human skin. Results from this study suggest that vitamin D producing LEDs can be developed for the treatment of vitamin D deficiency, especially in patients with fat malabsorption syndromes.
| Identifer | oai:union.ndltd.org:bu.edu/oai:open.bu.edu:2144/41743 |
| Date | 01 December 2020 |
| Creators | Veronikis, Angeline |
| Contributors | Holick, Michael F., Shirvani, Arash |
| Source Sets | Boston University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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