Analysis of Nutritional Components and Hypoglycemic Effect of Lecithin in Oncorhynchus masou Roes
WU Ruiyun, WANG An, CHEN Chunshan, SHANG Nan
1.College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; 2.Beijing Aquatic Wildlife Rescue and Conservation Centre, Beijing 102100, China; 3.College of Engineering, China Agricultural University, Beijing 100083, China
Abstract：The basic nutritional components of Oncorhynchus keta and Oncorhynchus masou roes including amino acids, minerals, vitamins and lecithin were analyzed by high performance liquid chromatography (HPLC). The effect of lecithin from Oncorhynchus masou roes on improving insulin resistance in HepG2 cells was evaluated by determining glucose absorption levels. The results showed that the contents of amino acids, vitamin B and lecithin in Oncorhynchus masou roes were significantly higher than those in Oncorhynchus keta roes; the lecithin content in Oncorhynchus masou roes was 234 mg/g, accounting for 23% of the total mass. Lecithin was the main component of the cell membrane, having many biological activities. The results of dipeptidylpeptidase-Ⅳ (DPP-Ⅳ) inhibition tests showed that lecithin had a potential hypoglycemic activity. Furthermore, glucose consumption was 3.87 mmol/L in the insulin resistance model group, significantly lower than in the normal control group (5.86 mmol/L) (P < 0.05), indicating successful modeling. Compared with the model group, lecithin from Oncorhynchus masou roes could improve the glucose consumption of insulin-resistant cells. The glucose consumption at a lecithin concentration of 800 μg/mL was 5.60 mmol/L, similar to that in the normal control group (5.86 mmol/L). Meanwhile, quantitative real-time polymerase chain reaction was used to detect the expression levels of the key enzymes in the insulin protein kinase B (Akt) signaling pathway, which indicated that lecithin reduced the relative expression levels of phosphoenolpyruvate carboxykinase (PEPCK), glucose-6-phosphatase (G6Pase), and glycogen synthase kinase 3β (GSK(3)β) genes in insulin-resistant HepG2 cells. Compared with the normal control group, the relative expression level of GSK(3)β was up-regulated by 2.60 folds in the model group, and the up-regulation fold was decreased to 1.59 in the lecithin-treated group. Lecithin increased the expression level of the glycogen synthase (GS) gene in hepatocytes and consequently promoted intracellular glycogen synthesis, increasing glycogen relative content from 30.67% to 73.00%, inhibited gluconeogenesis and improved the utilization of glucose in insulin-resistant HepG2 cells.
2021, Vol. 35 
