1. The effect of acute administration of Vitamin D on micro vascular endothelial function in Caucasians and South Asian Indians
- Author
-
Iman Akef Khowailed, Jinal Shah, Jerrold S. Petrofsky, Faris Alshammari, Rakhi Save, Guyeon Chung, Sophia Rodrigues, Siddhesh Akerkar, and Pooja Potnis
- Subjects
Adult ,Vitamin ,South asia ,Endothelium ,Dose ,Rest ,India ,Physiology ,vitamin D ,Pharmacology ,Vascular occlusion ,White People ,chemistry.chemical_compound ,Immune system ,Clinical Research ,medicine ,Vitamin D and neurology ,Humans ,Skin ,South Asian Indians ,business.industry ,General Medicine ,Blood flow ,endothelial cells ,medicine.anatomical_structure ,chemistry ,inflammation ,Regional Blood Flow ,Microvessels ,Endothelium, Vascular ,medicine.symptom ,Skin Temperature ,business - Abstract
Background Vitamin D is a modulator of the immune system. There is some limited evidence that it also increases local blood flow in response to stress. Material and methods In the present study, we examined 20 age matched subjects; 10 whom were from India and 10 Caucasians from the United States. Subjects were administered 4000 IU of Vitamin D3 for 3 weeks at breakfast. The function of the endothelial cells was evaluated in 2 ways; first, the response to 4 minutes of vascular occlusion was measured with a laser Doppler flow meter and second, the blood flow response to local heat at 42°C for 6 minutes. Results The results of the experiments showed that, as reported previously, the endothelial function in people from India was less than their Caucasian counterparts. The blood flow response to heat was reduced after 3 weeks administration of vitamin D in both groups and the response to vascular occlusion in the Caucasian group. But there was only a 20% reduction in the blood flow response to heat in the Caucasian group and a 50% reduction in the group from India. Conclusions Thus acute doses of vitamin D may increase vascular tone and reduce blood flow to tissue during stressors. Dosages administered for a longer duration may have beneficial effects on endothelial function but this was not examined here.
- Published
- 2013
- Full Text
- View/download PDF