How Does Vitamin D Modulate Human Health?
The mechanism by which vitamin D modulates human health has not yet been identified. However, it has been proposed that metabolic imprinting may be responsible for the long-term program effects of 25(OH)D. Metabolic imprinting is an adaptive process that fine tunes the expression of specific genes, without directly altering the DNA sequence, to produce a phenotype that is best suited to survive in its predicted environment.
To better understand the concept of metabolic imprinting, the human body can be thought of as a factory and metabolic imprinting as quality control. In a factory, quality control ensures that the product is designed and produced to meet or exceed consumer requirements. If the product is defective or if there is a possibility that it may malfunction in its given environment, minor modifications are used through various processes to optimize product success and longevity. However, these modifications can only be made if appropriate tools and resources (i.e., raw material) are available. Similarly, in the human body, metabolic imprinting, which takes place during critical windows of development such as the prenatal and neonatal stages of life, ensures that an array of differentiated tissues produces a phenotype that can survive in its given environment. If the phenotype is well matched to its environment, the organism will remain healthy; however, if there is any sort of mismatch, the organism's ability to respond to environmental challenges may be inadequate and risk of disease may be high. An overview of how vitamin D modulates system development and chronic disease susceptibility is summarized in Figure 2 and Table 1 and expanded upon below.
Summary of mechanisms by which a lack of vitamin D leads to disease. The arrows indicated by solid lines represent endocrine signals (i.e., molecules moving via the circulation to produce their effects). The large block arrows represent paracrine action of 25(OH)D (i.e., the effects of vitamin D produced by the local production of 1,25(OH)2D to permit communication between cells within each tissue). The arrows with light dashed lines represent mechanistic pathways. The asterisk (*) signifies that through a similar pathway, low plasma 25(OH)D can promote breast, prostate, or brain cancer.
J Midwifery Womens Health. 2010;55(6):550-560. © 2010
Elsevier Science, Inc.
Cite this: Relationship Between Vitamin D During Perinatal Development and Health - Medscape - Nov 01, 2010.