Yanik Rodríguez1, Armand B Christophe. 1. Department of Physiology and Biochemistry, Institute of Nutrition and Food Hygiene, Havana, Cuba.
Abstract
BACKGROUND: Associations have been described between insulin action and long-chain omega6 polyunsaturated fatty acids in skeletal muscle and erythrocytes of healthy individuals. We evaluated whether there was an association between insulin resistance and long-chain omega6 polyunsaturated fatty acids in erythrocyte phospholipids of type 2 diabetics. METHODS: Erythrocyte phospholipid fatty acid composition was determined in 43 adult non-obese type 2 diabetics. Insulin resistance was estimated by the HOMA mathematical approximations. Individual omega6 fatty acids and the sum of long-chain omega6 polyunsaturated fatty acids were correlated with insulin resistance. The same association was assessed for fatty acid product/precursor ratios taken as measures of Delta5 desaturase, Delta6 desaturase and their combined action. RESULTS: Except for 18:2omega6, 20:2omega6 and 20:3omega6, the individual omega6 fatty acids tested and the sum of long-chain omega6 polyunsaturated fatty acids correlated negatively with insulin resistance at p<0.005. Likewise, a negative correlation was found for the combined action of Delta5 and Delta6 desaturases (p<0.005). CONCLUSIONS: Our results indicate that formation of long-chain omega6 fatty acids from 18:2omega6 by desaturation-elongation is impaired under insulin resistant conditions and reduced desaturase activities may be involved. In view of our results, we hypothesize that in insulin resistant conditions, insulin-mediated activation of Delta5 and Delta6 desaturases may not occur.
BACKGROUND: Associations have been described between insulin action and long-chain omega6 polyunsaturated fatty acids in skeletal muscle and erythrocytes of healthy individuals. We evaluated whether there was an association between insulin resistance and long-chain omega6 polyunsaturated fatty acids in erythrocyte phospholipids of type 2 diabetics. METHODS: Erythrocyte phospholipid fatty acid composition was determined in 43 adult non-obese type 2 diabetics. Insulin resistance was estimated by the HOMA mathematical approximations. Individual omega6 fatty acids and the sum of long-chain omega6 polyunsaturated fatty acids were correlated with insulin resistance. The same association was assessed for fatty acid product/precursor ratios taken as measures of Delta5 desaturase, Delta6 desaturase and their combined action. RESULTS: Except for 18:2omega6, 20:2omega6 and 20:3omega6, the individual omega6 fatty acids tested and the sum of long-chain omega6 polyunsaturated fatty acids correlated negatively with insulin resistance at p<0.005. Likewise, a negative correlation was found for the combined action of Delta5 and Delta6 desaturases (p<0.005). CONCLUSIONS: Our results indicate that formation of long-chain omega6 fatty acids from 18:2omega6 by desaturation-elongation is impaired under insulin resistant conditions and reduced desaturase activities may be involved. In view of our results, we hypothesize that in insulin resistant conditions, insulin-mediated activation of Delta5 and Delta6 desaturases may not occur.
Authors: Natalie L Weir; Sarah O Nomura; Brian T Steffen; Weihua Guan; Amy B Karger; Ronald Klein; Barbara E K Klein; Mary Frances Cotch; Michael Y Tsai Journal: Clin Nutr Date: 2020-01-22 Impact factor: 7.324