Interestingly, a trend toward a dose–response relationship between vitamin D status and cognitive measures was also observed with subjects in the lowest quartiles of serum vitamin D performing lower on the Mini-Mental Status Examination than those in the upper quartiles, a finding that has been replicated in other Selinexor mw studies [211]. These studies do not demonstrate causality between serum vitamin D levels and cognitive status

especially given that vitamin D status may be a surrogate for other lifestyle factors that are difficult to control. That being said, with the increasing number of people affected by AD and the relative safety and cost-effectiveness of vitamin D supplementation, it may be beta-catenin activation reasonable to consider exploring a possible link between vitamin D and AD more

closely in well-controlled, prospective, longitudinal studies and/or clinical trials. Alzheimer’s disease susceptibility demonstrates a heritable component with recent GWAS pointing to an increasing number of genes of modest effect associated with late onset AD [212]. Genetic studies have supported a role for vitamin D in AD risk as evidenced by association of the disease with genetic variation in the vitamin D receptor gene (Vdr) [213-215]. The observation that VDR-binding sites are closely associated with several candidate AD susceptibility genes adds further support to this claim; however, detailed study exploring the role of vitamin D on gene expression and disease susceptibility is needed. The brain function of a selection of the AD susceptibility genes with associated VDR binding sites is outlined in Tables 4 [216-225]. This review has highlighted the extensively diverse role of vitamin D and its metabolites in both nervous system health and disease. The convergence of in vitro, ex vivo, and animal model data provides compelling evidence that vitamin D has a crucial role aminophylline in proliferation,

differentiation, neurotrophism, neuroprotection, neurotransmission, and neuroplasticity. Animal models have also contributed to our knowledge and understanding of the consequences of vitamin D deficiency on brain development and its implications for adult psychiatric and neurological diseases. The role of vitamin D likely goes beyond its direct function on cellular processes in that this secosteroid may influence the expression of genes via vitamin D response elements. The culmination of epidemiological, neuropathological, experimental, and molecular genetic findings certainly implicate vitamin D in influencing susceptibility to a number of psychiatric and neurological diseases, such as schizophrenia, autism, Parkinson’s disease, ALS, MS, and AD. Much more needs to be done to unravel how vitamin D deficiency may alter disease risk.