Association of Vitamin D Status with Neurobiological Biomarkers in Healthy Elderly Population

Alzheimer's disease (AD), the most prevalent type of dementia, is a progressive and irreversible neurological disorder that significantly disrupts social and occupational functioning due to cognitive and behavioral decline. It primarily affects older adults globally. Key factors like synaptic plasticity and neurotransmission in dopaminergic neural circuits is being contributed by vitamin D which offers its therapeutical capability and a new diagnostic tool.

This cross-sectional study was conducted at the Department of Biochemistry, Centre for Basic Sciences, KMC, Mangalore, involving 90 subjects aged between 45-65 with the different vitamin D status grouping them into Deficient (n=30), Insufficient (n=30) and optimum (n=30). Serum biomarkers, including Aβ42, BDNF, Calcium, Glutathione and Acetylcholinesterase, were analyzed using ELISA and spectrophotometric methods from stored samples. Statistical analysis was performed to explore the relationship between vitamin D status and cognitive related biomarkers.

This study analyzed neurobiological biomarkers in a study population of 90 individuals with different vitamin D status. Vitamin D status was significantly associated with Aβ42, BDNF, Calcium, Glutathione and Acetylcholinesterase. Individuals in the optimum group exhibited lower Aβ 42 levels and higher levels of BDNF, Calcium and Glutathione compared to deficient and insufficient groups indicating potential neuroprotective and antioxidant benefits.

Vitamin D offers a protective role in neurodegeneration in healthy aging adults, the more likely mechanisms being enhanced neurogenesis, improved antioxidant status and modulation of neuronal calcium as hallmarks of reducing the levels of the amyloid marker Aβ42. Amongst these, the effect of vitamin D in increasing BDNF was found to be most significant. Vitamin D does not seem to be involved in cholinergic pathway of neurodegeneration as observed in our study.