The Effect of N-Stearoylethanolamine on the Adipocyte Fatty Acid Composition of Different Age Rats With Obesity-Induced Insulin Resistance

Abstract

Chronic hypernutrition and high fat diet (HFD), rich in saturated fatty acids leads to molecular changes in insulin sensitive tissues and is followed by dyslipidemia. That is why the aim of our study was to investigate the fatty acid (FA) composition of phospholipids (PL), free fatty acids (FFA), triacylglycerol (TAG) and cholesterol esters (CE) of adipocytes in different age rats with HFD-induced insulin resistance (IR) and its changes under N-stearoylethanolamine (NSE) administration. The experimental model was induced on rats in age 10-month-old and 24-month-old by 6-month HFD and confirmed by the oral glucose tolerance test. NSE was administrated as water suspension per os in a dosage 50 mg/kg daily during 2 weeks. Adipocytes were isolated from abdominal fat using Type 1 Collagenase solution. Adipocytes lipid extract was separated on the fractions by thin-layer chromatography. The fatty acid composition of lipid fractions was analyzed by gas-liquid chromatography. Experimental data were processed statistically using Student's t-test. It was demonstrated, that prolonged HFD induces IR and leads to changes in FA profile of adipocytes PL, TAG, CE and composition of FFA in rats from two age groups. The results we obtained shoved that the aging process affects the fatty acid composition of adipocytes. Particularly, there was a significant decrease in the amount of fatty acids in the fractions of phospholipids, triacylglycerols and cholesterol esters together with a decrease in the percentage of unsaturated fatty acids. It was also demonstrated, that HFD significantly alters the fatty acid composition of all investigated adipocytes lipid fractions of younger age group rats, while similar changes were much less manifested in older age group of animals. NSE administration had a positive effect on the normalization of the fatty acid composition of the studied lipid fractions of both age group rat adipocytes. This study demonstrated that prolonged HFD induces obesity, increases the risk of type 2 diabetes development and leads to changes in adipocytes FA profile in rats from two age groups. As far as NSE administration had a positive effect on normalization of FA composition of adipocytes, we can consider NSE as a prospective agent for the treatment of obesity-induced complications and correction of age-related dyslipidemia.