The relationship between age and the fatty acid composition of cerebral cortex and erythrocytes in human subjects

The important role that neural tissue fatty acid composition plays in neuro development and various pathological states is increasingly recognized. How ever, there are limited data regarding the fatty acid composition of normal human brain at various ages. The purpose of this study was to describe hum an cerebral cortex fatty acid composition from ages 2 to 88 years. The rela tionship between cerebral cortex and erythrocyte fatty acid composition was also investigated. Samples of frontal cerebral cortex and of erythrocytes were obtained from 58 human subjects on whom autopsies were performed. The mean age of subjects was 40 +/- 29 years, with a range of 2 to 88 years. Th e fatty acid composition of tissues was determined, and linear regression m odels were used to describe the relationship between age and the fatty acid composition of cerebral cortex and erythrocytes. The data were bilinear, w ith changes occurring after the approximate age of 18 years. Therefore, the cohort was divided into subjects with ages less than or equal to 18 and gr eater than or equal to 18 years. In the younger group, the polyunsaturated fatty acids generally decreased with age, with the exception of 22:6n3, whi ch demonstrated a significant increase. The level of mono-unsaturated fatty acids, in contrast, generally increased to the age of 18 years. Several of the polyunsaturated fatty acids also decreased with age in the older cohor t, particularly 20:4n6. The levels of 18:2n6, however, increased significan tly with age in the older cohort. Among subjects less than or equal to 18 y ears of age, there was no significant relationship between cerebral cortex and erythrocyte fatty acid levels. In the older cohort, there was a signifi cant relationship between brain and erythrocyte levels for several fatty ac ids, particularly 16:0. These data demonstrate that levels of cerebral cort ex fatty acids change from early childhood through late adulthood, and indi cate that the levels of several erythrocyte fatty acids may be useful in pr edicting brain fatty acid levels in adults. (C) 2001 Elsevier Science Inc.