A combined supplementation of vitamin B12 and n-3 polyunsaturated fatty acids across two generations improves nerve growth factor and vascular endothelial growth factor levels in the rat hippocampus

Abstract

Vitamin B12 and n-3 polyunsaturated fatty acid (n-3 PUFA) are known to influence cognition. This study aims to examine if these nutrients affect the protein levels and gene expression of nerve growth factor (NGF) and vascular endothelial growth factor (VEGF) in the cortex and hippocampus in the second-generation offspring at 3 mo of age. Wistar rats were fed the following diets for two generations: Control (CON), vitamin B12 deficient (VBD), vitamin B12 deficient supplemented with n-3 PUFA (VBDO), vitamin B12 supplemented (VBS), vitamin B12 supplemented with n-3 PUFA (VBSO). The VEGF and NGF gene expression and protein levels in the hippocampus were lower (P⩽0.01) in the VBD group as compared to the CON group while the VBDO group restored the VEGF and NGF gene expression (P⩽0.01). The VBS group showed similar levels of NGF and VEGF to that of the CON group. However, the VBSO group demonstrated higher (P⩽0.05) NGF gene expression and protein levels in the hippocampus and higher cortex NGF protein levels as compared to the CON group. In addition, VEGF (in hippocampus) and NGF (in cortex and hippocampus) protein levels were also higher (P⩽0.05) in the VBSO group as compared to the VBS group. Our results indicate that the combined supplementation of vitamin B12 and n-3 PUFA improves NGF and maintains VEGF levels in the brain which may improve neurovascular function.