Tag Archives: experimental insulin resistance
The effect of N-stearoylethanolamine on adipocytes free cholesterol content and phospholipid composition in rats with obesity-induced insulin resistance
O. S. Dziuba, Ie. A. Hudz, H. V. Kosiakova, T. M. Horid’ko, V. M. Klimashevsky, N. M. Hula
Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: oksana.dziuba86@gmail.com
Obesity induces molecular changes that promote associated disorders, such as insulin resistance (IR) and type 2 diabetes. Low insulin sensitivity occurs primarily due to defects in the pathway of insulin action in target tissues, and there is a hypothesis that IR may originate in adipose tissue and is followed by dyslipidemia. In this study using methods of thin-layer and gas-liquid chromatography we investigated free cholesterol content and phospholipid composition of adipocytes of obesity-induced IR rats and its changes induced by the N-stearoylethanolamine (NSE) administration. The results we obtained demonstrated that free cholesterol content significantly increased in adipocytes of IR rats compared to control. The analysis of phospholipid composition indicated a reduction of phosphatidylcholine and the total content of phosphatidylinositol with phosphatidylserine, whereas the content of lysophosphatidylcholine, sphingomyelin and phosphatidylethanolamine increased in IR group compared to control. NSE administration caused a statistically significant decrease in total cholesterol level and had a considerable effect on normalization of individual phospholipids content. As far as NSE administration caused a statistically significant decrease in free cholesterol level and had a considerable effect on normalization of individual phospholipids content of adipocytes, we can consider NSE as a prospective compound worthy more complex investigation of its action under the pathological conditions.
The effect of N-stearoylethanolamine on cholesterol content, fatty acid composition and protein carbonylation level in rats with alimentary obesity-induced insulin resistance
O. V. Onopchenko, G. V. Kosiakova, E. F. Meged,
V. M. Klimashevsky, N. M. Hula
Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: onop.89.av@mail.ru
The effect of N-stearoylethanolamine (NSE) on liver free fatty acid composition, cholesterol content and carbonylated protein level in rats with obesity-induced insulin resistance (IR) was studied in the work. The experimental insulin resistance was induced by prolonged high fat diet (58% of energy derived from fat) for 6 months combined with one injection of low-dose (15 mg/kg) of streptozotocin. The lipid assay showed a rise in liver free cholesterol content and a significant reduction in cholesterol esters level. Analyzing liver fatty acid composition, a decrease in polyunsaturated of fatty acid (PUFA) level and an increase in monounsaturated fatty acid (MUFA) content was found. Fatty acid imbalance with high content of MUFA was associated with elevated level of protein carbonylation. The NSE administration (50 mg/kg of body weight) for 2 weeks decreased free cholesterol content, increased cholesterol esters level and reduced free oleic fatty acid content in the liver of rats with IR. The effect of NSE on lipid imbalance led to a decrease in protein carbonylation level that may result in improvement of transmembrane protein function under obesity-induced insulin resistance state.
The effect of N-stearoylethanolamine on plasma lipid composition in rats with experimental insulin resistance
O. V. Onopchenko, G. V. Kosiakova, V. M. Klimashevsky, N. M. Hula
Palladin Institute of Biochemistry, National Academy
of Sciences of Ukraine, Kyiv;
e-mail: onop.89.av@mail.ru
A model of insulin resistance (IR), induced by prolonged high fat diet with high content of saturated fats was used to investigate the effect of N-stearoylethanolamine (NSE) on the composition of free fatty acids (FFA), plasma lipoprotein spectrum and content of proinflammatory cytokine TNFα in rats. The results of this work showed a rise in the content of monounsaturated fatty acids (18:1 n-9) and a reduction in the level of polyunsaturated fatty acids (20:4 n-6) in plasma of rats with experimental IR. These findings are accompanied by the increased TNFα production and significant changes in plasma lipoprotein profile of rats with the fat overload. Particularly, a decreased high-density lipoprotein (HDL) cholesterol level and increased low-density (LDL) and very low-density lipoprotein (VLDL) cholesterol level were detected. The NSE administration to obese rats with IR restored the content of mono- and polyunsaturated FFA, increased HDL cholesterol content and reduced LDL cholesterol level. In addition, the IR rats treated with NSE showed normalization in the serum TNFα level. Our results showed the restoration of plasma lipid profile under NSE administration in rats with obesity-induced IR. Considering the fact that plasma lipid composition displays the lipid metabolism in general, the NSE actions may play a significant role in the prevention of IR-associated complications.