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Plasma 25-hydroxyvitamin D levels are favorably associated with β-cell function
Rudruidee Karnchanasorn1, Horng-Yih Ou, Ken C Chiu
1Department of Clinical Diabetes, Endocrinology, and Metabolism, City of Hope National Medical Center, Duarte, CA, USA.
Pancreas
|January 20, 2012
Summary
Vitamin D deficiency is linked to impaired insulin sensitivity and beta-cell function. This study highlights vitamin D
Area of Science:
- Endocrinology
- Metabolic Diseases
- Nutritional Science
Background:
- Hypovitaminosis D (vitamin D deficiency) is recognized as a factor in type 2 diabetes.
- While linked to insulin resistance, its specific impact on human beta-cell function is less understood.
Purpose of the Study:
- To investigate the relationship between plasma 25-hydroxyvitamin D [25(OH)D] levels and both insulin sensitivity and adjusted beta-cell function (ABCF) in healthy individuals.
Main Methods:
- 150 healthy, glucose-tolerant subjects underwent hyperglycemic clamp tests.
- Beta-cell function (acute insulin response) and insulin sensitivity index (ISI) were measured.
- Adjusted beta-cell function (ABCF) was calculated as the product of acute insulin response and ISI.
Main Results:
- Plasma 25(OH)D levels showed a significant positive association with ABCF (P = 0.00004).
- Plasma 25(OH)D levels were also positively associated with ISI (P < 0.00001).
- These associations remained significant after adjusting for multiple demographic and lifestyle factors.
Conclusions:
- Higher plasma 25(OH)D levels correlate with improved beta-cell function and insulin sensitivity.
- These findings suggest that vitamin D deficiency may contribute to the dual defects observed in type 2 diabetes pathogenesis.
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