Desaturation Function Does Not Decline after Menopause in Human Females

Aging appears to decrease Δ6-desaturase activity in males, but in females it is uncertain. Δ6- and Δ5-desaturase functions were investigated in pre- and post-menopausal women who were normoglycemic or had type 2 diabetes (2 × 2 factorial, n = 37). Subjects were compared for indicators of diabetic control, estrogen levels, fatty acid profiles and indices of Δ6-and Δ5-desaturase activity. Diet intakes that were compared to determine whether results were a function of dietary factors known to influence desaturase activity revealed no differences (P > 0.05). Post-menopausal women with type 2 diabetes had more 18:2 n6 in serum phospholipids (P < 0.05) than did the pre- and post-menopausal control subjects. Fatty acid ratios of 18:3 n6/18:2 n6 indicated greater Δ6-desaturase activity for women with type 2 diabetes, but differences were not found between pre- and post-menopausal groups. Significant correlation (P < 0.05) indicates an association between diabetic status and desaturase function, but function did not appear to be affected by menopausal status. In contrast to reports using male subjects, we found no evidence that desaturase function decreased in aging females, as reported for males, or increased as hypothesized in this study.

Key words

Δ6-Desaturase - Δ5-Desaturase - Aging - Type 2 Diabetes - Insulin - Estrogen