Vitamin D deficiency may be linked to the dysfunction of the hippocampus – a region of the brain thought to play a role in schizophrenia, say researchers.
Researchers from the National Institute of Mental Health and Neuroscience (NIMHANS) in India and the Harvard Medical School in the US looked at the serum vitamin D levels and the brain of 35 schizophrenia patients with an average age of 32.
They found 34 of the patients had sub-optimal levels of serum vitamin D - 83% of which equated to deficiency and 14% insufficiency.
A “significant positive correlation” was also seen between vitamin D and regional grey matter volume in the right hippocampus.
Previous research had suggested vitamin D supplementation may reduce the risk of schizophrenia in infants while another paper linked deficient serum levels with first-episode psychosis.
However this latest paper was the first to look at serum vitamin D levels and hippocampal volume in schizophrenia.
The hippocampus is one of the brain regions with maximum concentrations of vitamin D receptors and the vitamin has been shown to play a critical role in hippocampal cell survival through its neuroprotective effects.
They said the relationship could be due to vitamin D’s impact on neuron-supporting neurotrophin proteins, the nervous system’s interaction with the immune system and the excretion of amino acids.
“Since deficient brain-derived neurotrophic factor and increased oxidative stress have been associated with schizophrenia, these effects mediated by vitamin D through vitamin D receptors could be critical in this disorder,” the wrote in Psychiatry Research: Neuroimaging.
The hippocampus - named after its resemblance to a seahorse - is thought to play a key role in emotions and memory.