Vitamin D deficiency influences fatty acid metabolism

Reports indicate that maternal vitamin D deficiency may be associated with increased inflammation. Long chain polyunsaturated fatty acids (LCPUFAs); omega-3 and omega-6 fatty acids are known to have anti-inflammatory and pro-inflammatory properties respectively. The present study examines the effect of vitamin D deficiency on fatty acid composition and metabolism in a rat model. Female Wistar rats were randomly divided into two groups (n = 8/group) as follows; control and vitamin D deficient (VDD). Diets (control: 1000 IU D3/kg diet; VDD: 0 IU D3/kg diet) were given from weaning and continued throughout pregnancy. Pregnant female rats were dissected on gestational day 20 to collect blood, liver and placenta. The VDD diet reduced maternal serum 25-hydroxyviatmin D3 levels (p < 0.001) as compared to control. Maternal vitamin D deficiency resulted in lower total weight gain and placental weight (p < 0.05 for both) during pregnancy. Animals from VDD group demonstrated higher arachidonic acid (AA) levels in both the liver and plasma (p < 0.05 for both) as compared to control. Liver, plasma and placental monounsaturated fatty acid levels (MUFA) were lower (p < 0.01 for all) while plasma total saturated fatty acids (SFA) (p = 0.05) were higher in the VDD group. Animals from the VDD group demonstrated lower Delta 9-desaturase activity index (p < 0.01 for all) in the liver, plasma and placenta. The plasma Delta 5-desaturase activity index (p < 0.05) was higher although no change was observed in the Delta 6-desaturase activity index. However, the mRNA levels of liver Delta 6-desaturase was lower (p < 0.05) in the VDD group. Our findings indicate that maternal vitamin D deficiency influences fatty acid desaturase activity and expression and therefore alters maternal fatty acid metabolism.