Vitamin D biology and heart failure: Clinical and experimental studies

In the last decade, vitamin D biology has been studied more extensively than ever before.. The use of vitamin D supplements is common, and so is determination of plasma vitamin D status. Besides its role in bone homeostasis, vitamin D is thought to be an important player in the development and treatment of other diseases as well. This thesis therefore tested if vitamin D status is of importance in prevention and treatment of disease, and in particular heart failure. It describes that individuals with low levels of vitamin D often have more diseases, including cardiovascular disease. However, it also shows that in an experimental heart failure model, vitamin D supplementation does not reduce thickness of heart muscle wall, although it protects against stiffness and amount of scar tissue in the heart muscle. It appears that vitamin D and parathyroid hormone are no predictors of heart failure. The role for vitamin D as novel target in heart failure is not straightforward and may be limited. Nevertheless, at this stage, a potential utility of vitamin D supplementation or VDR activation cannot be ruled out yet. This thesis furthermore shows that low levels of vitamin D during pregnancy may influence health status in the offspring. Vitamin D deficiency has been related to epigenetic changes that are associated with increase in blood pressure. Low vitamin D in adults could therefore not only be a risk factor for development of disease in an individual, but could also affect future generation(s)