Vitamin D and brain

    There is evidence linking gestational and/or neonatal vitamin D deficiency with an increased risk of neurodevelopmental disorders such as schizophrenia and autism, and vitamin D deficiency in adults with certain degenerative conditions. Regarding neurotransmission, there is strong evidence (experimental models include cells and rodents) that vitamin D is important for the development and maintenance of dopamine signaling in the brain (the brain chemical most associated with motivation and reward-driven behavior). There is cellular data suggesting that vitamin D deficiency may also negatively affect the serotonergic system.

    In developing brains, the vitamin D receptor can be found early, around the time when most dopamine neurons are born. Vitamin D deficient brains (rodents) have been shown to have reduced numbers of specific proteins that are critical for dopamine neuron maturation (depletion of these proteins results in reduced numbers of dopamine cells and altered positioning of dopamine neurons - this has been shown to negatively affect dopamine metabolism later in life). Furthermore, another study has shown that vitamin D deficiency in the developing brain results in reduced expression and protein levels of tyrosine hydroxylase (the rate-limiting enzyme for dopamine production). The same study demonstrated that the same brains had reduced levels of BDNF (another study showed reduced Nerve Growth Factor) during critical periods of development.

    In models of neurodegeneration (rodents), the active hormonal form of vitamin D has been shown to protect against and in some cases alleviate specific disease pathology. For example, acute administration has been shown to protect dopamine neurons in different models of Parkinson's (by increasing tyrosine hydroxylase activity).

References

DOI: 10.1002/jbm4.10419

DOI: 10.1016/j.neulet.2009.05.070

DOI: 10.1016/j.bbr.2015.03.008

DOI: 10.1016/j.neuroscience.2016.07.020

DOI: 10.1002/jnr.21878