High-dose dietary supplementation of vitamin A induces brain-derived neurotrophic factor and nerve growth factor production in mice with simultaneous deficiency of vitamin A and zinc

Department of Nutrition and Metabolism, University of Tokushima Graduate School, Tokushima, Japan.
Nutritional Neuroscience (Impact Factor: 2.11). 11/2008; 11(5):228-34. DOI: 10.1179/147683008X301603
Source: PubMed

ABSTRACT Marginal vitamin A and zinc (Zn) deficiency often co-exist in many populations. Vitamin A plays a trophic role in brain and is important for its development. We investigated effects of dietary supplementation of vitamin A on brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) production in mice depleted for vitamin A and Zn. After 3 months' feeding with a low vitamin A and Zn (LVA-LZ) diet, mice were divided into two groups and replenished with either normal or high vitamin A with low Zn diet for an additional 2 months. Levels of BDNF and NGF were measured from extracts of hippocampus, cortex and cerebellum at the end of the third and fifth months. The LVA-LZ group tended to show decreased amounts of the BDNF and NGF, while animals supplemented with high vitamin A along with Zn deficiency had high BDNF and NGF concentrations. From these results, we conclude that vitamin A may increase BDNF and NGF levels.

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