The Neuroprotective Potential of Vitamin D₃

Vitamin D₃ plays a pivotal role not only in bone health but also in the functioning of the nervous system, particularly in the context of age-related neurodegenerative diseases such as Alzheimer's disease, multiple sclerosis, and Parkinson's disease. Vitamin D₃ deficiency has been associated with cognitive decline, heightened inflammation, and shortened leukocyte telomere length, which may contribute to accelerated cellular aging. Therapeutic interventions involving vitamin D₃ have been reported in selected clinical studies and meta-analyses to potentially enhance cognitive function, decrease amyloid β biomarkers, and prolong telomere length, although heterogeneity remains across study designs and populations. Furthermore, vitamin D₃ has been shown to influence the expression of genes implicated in DNA repair and oxidative stress response, including NRF2, OGG1, MYH, and MTH1. This narrative review synthesizes current knowledge on the molecular mechanisms of vitamin D₃ action in the context of neuroprotection and discusses potential directions for future research, including its possible therapeutic applications in neurodegenerative diseases.