Tag Archives: adipose tissue
Diet-induced and age-related changes in rats: the impact of N-stearoylethanolamine intake on plasma lipoproteins, adiponectin, and adipocyte cholesterol-phospholipid composition
O. S. Tkachenko*, H. V. Kosiakova
Palladin Institute of Biochemistry,
National Academy of Sciences of Ukraine, Kyiv, Ukraine;
*e-mail: 888oksana.tkachenko@gmail.com
Received: 26 January 2024; Revised: 19 March 2024;
Accepted: 19 March 2024; Available on-line: 30 April 2024
Adiponectin is secreted by adipose tissue, associated with lipoprotein (LP) metabolism, down-regulated in insulin resistance states, and reduced in individuals suffering from obesity and cardiovascular diseases. Phospholipids and cholesterol are the main components of cell membranes and play a critical role in storage and secretory adipocyte functions. N-stearoylethanolamine (NSE) is a minor lipid affecting cell membrane lipids’ composition. Our study aimed to investigate plasma levels of adiponectin and cholesterol of low- and high-density LP (LDL and HDL) and adipocyte cholesterol-phospholipid (Chol-PL) composition of different age rats with high-fat diet (HFD)-induced obesity and insulin resistance and their changes under NSE administration. Our study demonstrated that chronic dietary fat overloading leads to obesity accompanied by impairment of glucose tolerance, a manifestation of dyslipidemia, and changes in plasma adiponectin levels in rats from two age groups (10-month-old and and 24-month-old). Prolonged HFD led to a reduction in plasma adiponectin levels and the growth of adipocyte cholesterol content in rats of different ages. A significant increase in plasma LDL-Chol level and main adipocyte PLs (phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, and lysophosphatidylcholine) was observed in younger rats, whereas not detected in elder animals after dietary fats overloading. The decrease in the content of anionic phospholipids (phosphatidylinositol + phosphatidylserine) was also detected in 10-month-old HFD rats compared to the control animals. NSE administration positively affected the normalization of adiponectin levels in both age HFD groups. It significantly impacted the reduction of LDL-Chol levels and the growth of HDL-Chol concentration in the blood plasma of 10-month-old rats as well as PL-composition of young HFD rats and anionic PL restoring in 24-month-old rats. The positive effect on investigated parameters makes NSE a prospective agent for treating diet-induced and age-related metabolic disorders threatening cardiovascular diseases.
Insulin resistance in obese adolescents and adult men modifies the expression of proliferation related genes
O. H. Minchenko1, Y. M. Viletska1, D. O. Minchenko1,2, V. V. Davydov3
1Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: ominchenko@yahoo.com;
2Bohomolets National Medical University, Kyiv, Ukraine
3SI “Institute of Children and Adolescent Health Care,
National Academy of Medical Sciences of Ukraine”, Kharkiv
Received: 11 December 2018; Accepted: 14 March 2019
Numerous data demonstrate that key regulatory factors, enzymes and receptors including HSPA5, MEST, SLC1A3, PDGFC, and ADM represent poly-functional, endoplasmic reticulum stress-dependent proteins, which control variable metabolic pathways. The expression level of genes of these proteins in the blood and subcutaneous adipose tissue of obese adolescents and adult men with and without insulin resistance was studied. It was shown that in blood of obese adolescents without insulin resistance the expression level of SLC1A3, HSPA5, MEST, and PDGFC genes was significantly increased, but development of insulin resistance led to down-regulation of these genes expression except HSPA5 gene as compared to the control group as well as to the group of obese adolescents without insulin resistance. At the same time, the expression level of ADM gene did not change significantly in obese adolescents without insulin resistance, but the development of insulin resistance led to down-regulation of this gene expression. In subcutaneous adipose tissue of obese adult men without insulin resistance the level of SLC1A3 gene expression was decreased, although ADM, MEST, and HSPA5 genes – increased. It was also shown that the development of insulin resistance in obese men affected the expression level of ADM and SLC1A3 genes only. Results of this investigation provide evidence that insulin resistance in obese adolescents and adult men is associated with specific changes in the expression of genes, which related to proliferation and development of obesity and insulin resistance as well as to endoplasmic reticulum stress and contribute to the development of obesity complications.
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.