Effect of postlactation iron deficiency on the composition of fatty acids of whole brain myelin

Abstract

The composition of myelin fatty acids isolated from Wistar male rat brains was analysed after induction of nutritional iron-deficiency from postnatal days 21-63. From whole brain, myelin was obtained as the fraction of total lipids by phase separation under mildly acidic conditions. Fatty acids were separated by methylation and determined by gas chromatography. Significant differences in the polyunsaturated fatty acids n-6/n-3 relationship as well as an increment of eicosapentaenoic, eicosadienoic and docosadienoic acids and a reduction of stearic acid were determined in iron-deficient rats. The observed changes of myelin fatty acid expression strongly suggest an increased membrane fluidity, possibly affecting its three-dimensional structure, something which could partially correlate with the cognitive and psychomotor impairments observed in iron-deficient children and adolescents. Due to the fact that no significant differences have been observed in brain weight or size under iron deficiency, the increased expression of eicosapentaenoic acid (EPA) during postlactation development may play a moderately neuroprotective role.