Dopamine increased with vitamin D supplementation (in rats)
The Vitamin D Content of a High-Fat Diet Modulates Brain Reward Neurochemistry
The FASEB Journal, vol. 30 no. 1 Supplement lb202 , April 2016
Ruslan Kubant1, Diptendu Chatterjee1, Emanuela Pannia1 and G. Harvey Anderson1,2
1Nutritional Sciences, University of Toronto, Toronto, ON, Canada
2Physiology, University of Toronto, Toronto, ON, Canada
Background Obesity is associated with increased consumption and preference for palatable foods as well as reduced blood levels of 25[OH]D3, which has been linked to altered dopaminergic and serotonergic signalling in the brain. The effect of vitamin D on high fat diet induced changes in brain reward systems is unknown.
Objective To determine if vitamin D plays a role in modulating hedonic regulation of food intake in the brain in response to chronic consumption of a high fat diet.
Methods and Design Male Wistar rats at 21 days of age were fed ad libitum for 14 weeks a high-fat diet (60 kcal% fat) containing either: 1) the recommended amount (1,000 IU/kg diet) of vitamin D3 (HF-RD) or 2) high vitamin D3 (HF-HD, 7-fold increase of the recommended amount). Rats fed a normal-fat diet with the recommended amount of vitamin D3 (NF-RD, 16 kcal% from fat) served as control. Body weight, food intake, serum 25[OH]D3, and concentrations of dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA) were measured in the nucleus accumbens (NAc) and β-endorphin in the ventral tegmental area (VTA). DA and 5-HT turnover rates were calculated by the ratio of their primary metabolites DOPAC to DA and 5-HIAA to 5-HT respectively, and used as an index of dopamine/serotonin transmission.
Results The HF-RD group consumed more calories and gained more weight than the NF-RD group as well as exhibited increased DA (48%, P<0.05), DOPAC (330%, P<0.05), dopamine turnover (195%, P<0.05), 5-HT (85%, P<0.05), 5-HIAA (51%, P<0.05), and lower serotonin turnover (16%, P<0.05) in NAc. VTA levels of β-endorphin were lower (46%, P<0.05) in the HF-RD group compared to the NF-RD. Supplementation of a HF diet with high vitamin D3 for 14 weeks resulted in a 3-fold increase (P<0.05) in serum 25[OH]D3 and reduction (≈30%, P<0.05) in DOPAC levels and dopamine turnover compared to the HF-RD group, but had no statistically significant effect on food intake, body weight, 5-HT, 5-HIAA, serotonin turnover rate or β-endorphin levels in the brain.
Conclusion The vitamin D content of a high-fat diet modulates brain reward neurochemistry and may be a factor in neurotransmitter-mediated regulation of the reward-seeking behaviors.
Support or Funding Information
Canadian Institute of Health Research, Institute of Nutrition, Metabolism and Diabetes (CIHR-INMD), Reference MOP-130286.
This abstract is from the Experimental Biology 2016 Meeting.
There is no full text article associated with this abstract published in The FASEB Journal.