Vitamin D3 Therapy Corrects the Tissue Sensitivity to Angiotensin II Akin to the Action of a Converting Enzyme Inhibitor in Obese Hypertensives: An Interventional Study
Year: 2012
Type: article
Study design: Clinical Trial
Abstract: CONTEXT: Vitamin D deficiency and obesity are associated with increased tissue renin-angiotensin system (RAS) activity. OBJECTIVE: The objective of the study was to evaluate whether vitamin D(3) therapy in obesity reduces tissue-RAS activity, as indicated by an increase in tissue sensitivity to angiotensin II (AngII). PARTICIPANTS: Participants included obese subjects with hypertension and 25-hydroxyvitamin D less than 25 ng/ml. DESIGN: Subjects were studied before and after 1 month of vitamin D(3) 15,000 IU/d, while in dietary sodium balance, and off all interfering medications. Fourteen subjects successfully completed all study procedures. SETTING: The study was conducted at a clinical research center. OUTCOME MEASURES: At each study visit, tissue sensitivity to AngII was assessed by measuring renal plasma flow (RPF), mean arterial pressure (MAP), and adrenal secretion of aldosterone during an infusion of AngII. Subjects were then given captopril, and a second AngII infusion to evaluate the effect of captopril on tissue-RAS activity. RESULTS: Vitamin D(3) therapy increased 25-hydroxyvitamin D (18 to 52 ng/ml) and basal RPF (+5%) and lowered supine MAP (-3%) (all P < 0.01). There was a greater decline in RPF and higher stimulation of aldosterone with AngII infusion after vitamin D(3) therapy (both P < 0.05). As anticipated, captopril increased the renal-vascular, MAP, and adrenal sensitivity to AngII, but this effect was much smaller after vitamin D(3) therapy, indicating that vitamin D(3) therapy corrected the tissue sensitivity to AngII akin to captopril. CONCLUSIONS: Vitamin D(3) therapy in obese hypertensives modified RPF, MAP, and tissue sensitivity to AngII similar to converting enzyme inhibition. Whether chronic vitamin D(3) therapy abrogates the development of diseases associated with excess RAS activity warrants investigation.
DOI: 10.1210/jc.2012-1156
Institutions: Brigham and Women's Hospital, Harvard University
Language: English
Subfield: Cardiology and Cardiovascular Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
Awards: Informatics for Integrating Biology & the Bedside (i2b2), G1487753052, Vitamin D Deficiency Augments Renin-Angiotensin System Activity in Obesity, G2496518617, Harvard Clinical and Translational Science Center (UL1), G3740841103, General Clinical Research Center, G455375549, Training Program in Hypertension, SCOR MOLECULAR GENETICS OF HYPERTENSION, Vitamin D and Hormonal Mechanisms of Cardiovascular Disease in Obesity, G9000195782
OpenAlex ID: W2061737727