1,25-dihydroxyvitamin D3 triggers an anti-inflammatory response in brain pericyte

Background: Epidemiology and experimental studies suggest 1,25-dihydroxyvitamin D3 plays a neuroprotective role in neurodegenerative diseases including Alzheimer's disease. Most of the experimental data on the genes regulated by this hormone in brain cells have been obtained with neuron and glial cells. Emerging evidence demonstrates pericyte plays a critical role in brain function that encompasses its classical function in the control and maintenance of the blood brain barrier. However, the gene response of brain pericyte to 1,25D remains to be investigated. Methods: The transcriptomic response of human brain pericytes to 1,25-dihydroxyvitamin D3 was analyzed. Results were confirmed by RT-qPCR for the genes of interest. Results: We demonstrate that human brain pericyte in culture responds to 1,25-dihydroxyvitamin D3 by regulating genes involved in the control of neuro-inflammation. We also showed that pericytes respond to the pro-inflammatory cytokines TNF-alpha and Interferon gamma by inducing the expression of the gene involved in the synthesis of 1,25-dihydroxyvitamin D3 named CYP27B1. Conclusion: Taken together these results suggest that neuro-inflammation could trigger the synthesis of 1,25-dihydroxyvitamin D3 by brain pericytes, which will in turn respond to the hormone by a global anti-inflammatory response. Four samples were analysed, two replicates for control samples and two replicates treated with 1,25D3.