Adverse effect of obesity on red cell membrane arachidonic and docosahexaenoic acids in gestational diabetes.

Gestational diabetes is a metabolic disorder affecting 2-5% of women and is a predictor of obesity, Type 2 diabetes mellitus and cardiovascular disease. Insulin resistance, a characteristic of gestational diabetes and obesity, is correlated with the fatty acids profile of the red cell and skeletal muscle membranes. We investigated the plasma and red cell fatty acid status of gestational diabetes. The effect of obesity on membrane fatty acids was also examined. Fasting blood obtained at diagnosis was analysed for the fatty acids in plasma choline phosphoglycerides and red cell choline and ethanolamine phosphoglycerides. There were reductions in arachidonic acid (controls 10.74+/-2.35 vs gestational diabetes 8.35+/-3.49, p<0.01) and docosahexaenoic acid (controls 6.31+/-2.67 vs gestational diabetes 3.25+/-2.00, p<0.0001) in the red cell choline phosphoglycerides in gestational diabetes. A similar pattern was found in the ethanolamine phosphoglycerides. Moreover, the arachidonic and docosahexaenoic acids depletion in the red cell choline phosphoglycerides was much greater in overweight/obese gestational diabetes (arachidonic acid=7.49+/-3.37, docosahexaenoic acid=2.98+/-2.18, p<0.01) compared with lean gestational diabetes (arachidonic acid=10.03+/-2.74, docosahexaenoic acid=4.18+/-1.42). Apparently normal plasma choline phosphoglycerides fatty acids profile in the gestational diabetic women suggested that membrane lipid abnormality is associated specifically with perturbation in the membrane. The fact that the lipid abnormality is more pronounced in the outer leaflet of the membrane where most of receptor binding and enzyme activities take place might provide an explanation for the increased insulin resistance in gestational diabetes and obesity.