Vitamin D (Calcifediol) Supplementation Modulates NGF and BDNF and Improves Memory Function in Postmenopausal Women: a Pilot Study

Abstract

1,25-dihydroxy vitamin D (vitamin D), a steroid hormone essential for calcium metabolism and various extra skeletal functions, is an in vitro inducer of Nerve Growth Factor (NGF) and modulates Brain-Derived Neurotrophic Factor (BDNF) in neurons, while its receptor is expressed in central nervous system. Due to restricted sunlight exposure and/or dietary intake many people are vitamin D–deficient and need supplementation. Vitamin D status has been associated with impairment in cognitive functions, but up to now no clinical studies have been conducted to verify its effect on neurotrophins and memory in humans. 20 postmenopausal women with low vitamin D levels were treated by calcifediol (25-OH D3) and followed in open for three months. At baseline and after three months NGF and BDNF together with Wechsler Memory Scale (WMS) were assessed. Mean plasma vitamin D levels were 14.52 (+/-5.65 SD) ng/ml at baseline and 47.58 (+/-15.05 SD) ng/ml after three months of supplementation. At the end of the study a statistical significant decrease in both neurotrophins was observed. NGF plasma levels were respectively: 451.13 (+/-243.20 SD) pg/ml and 323.68 (+/-195.60 SD) pg/ml (p=0.05); BDNF levels were 431.10 (+/-182.21 SD) pg/ml and 366.25 (+/-142.75 SD) pg/ml (p=0.02). WMS scored meanly 97.00 (+/-13.54 SD) at baseline and 107.82 (+/-16.19 SD) after three months (p=0.003). Considering the role of vitamin D in calcium metabolism and neurotrophic factors regulation, it seems indispensable in brain function and its deficiency must be considered in cognitive diseases.