Sea cucumber derived sulfated sterols (SS) significantly ameliorated insulin resistance and decreased lipid accumulation compared to plant sterols. Interestingly, our recent study found that intervention with sea cucumber sulfated sterols could significantly increase blood glucose levels of healthy mice in the presence of glucose, while cholesterol sulfate, as one of sulfated sterols, did not have the same effect. However, the exact mechanism of SS on glucose metabolism is still unknown. In the present study, we investigated the potential mechanism by which SS influenced blood glucose homeostasis in healthy mice. Results showed that intervention with sea cucumber sulfated sterols did not affect the levels of hormones related to glucose metabolism, while led to a significant decrease in the synthesis of liver glycogen and muscle glycogen. Besides, the expression of proteins associated with the promotion of gluconeogenesis dramatically increased in the mice intervened with sea cucumber sulfated sterols. These findings suggested that sea cucumber sulfated sterols might change blood glucose metabolism in healthy mice by reducing glycogenesis and promoting gluconeogenesis.

Trimethylamine N-oxide (TMAO) is a risk factor of various chronic diseases, which was produced by metabolism from precursors to trimethylamine (TMA) in gut and the oxidation from TMA in liver. The TMA generation was influenced by diet, mainly due to the rich TMAO precursors in diet. However, it was still unclear that the effects of different proportion and source of macronutrients in different dietary pattern on the production process of TMAO. Here, the generation of TMA from precursors and TMAO from TMA was determined after single oral choline chloride and intraperitoneal injection TMA, respectively, in mice fed with carbohydrates, proteins and fats in different proportion and sources. The results suggested that the generation of TMAO was increased by low non-meat protein and high fat via enhancing the production of TMAO from TMA, and decreased by plant protein and refined sugar via reducing TMA production from precursors in gut and TMAO transformation from TMA in liver. The high fat and high sugar diets accelerating the development of atherosclerosis did not increase the production of TMAO, the risk factor for atherosclerosis, which indicated that the dietary compositions rather than the elevated TMAO level might be a more key risk factor for atherosclerosis.

Sea cucumber saponins have attracted more attention in recent years due to biological activities. It is a popular practice to soak sea cucumber in Baijiu at home and being applied to industrial manufacturing in China. However, knowledge of the effect of alcohol on the absorption and metabolism of sea cucumber saponins is limited. The effects of alcohol on digestion, absorption and metabolism of sea cucumber saponins in BALB/c mice were investigated after gavage and tail intravenous injection. The results showed that the content of saponins in serum and liver was significantly higher under the influence of alcohol than that in the control group after oral administration. Alcohol promoted the absorption of sea cucumber saponins prototype as well as inhibited the process of saponins being transformed into deglycositic metabolites in the small intestine. Moreover, sea cucumber saponins remained in circulation for a long time and alcohol slowed down the clearance of sea cucumber saponins under the influence of alcohol after intravenous injection. This confirmed the feasibility of marinating sea cucumber in Baijiu to improve the efficacy of saponins and provides an important theoretical basis for the utilization of sea cucumber and the development of sea cucumber liquor.

Antarctic krill (Euphausia superba) oil has been gaining increasing attention due to its nutritional and functional potentials. Krill oil usually contains a high concentration (about 50%) of phospholipids (AKOP) rich in DHA and EPA accompanied with 30%–40% triacylglycerols. Phospholipids can be made into liposomes without emulsifiers due to its amphiphilic characteristics. However, the absorption kinetics of AKOP liposome in vivo is not clear, which restrict the molecular mechanism analysis related to its distinct bioactivities. The lipid analysis in serum, small intestinal content and wall was carried out after oral administration of AKOP liposome to illustrate its absorption kinetics in blood and the digestive tract of healthy mice by single gavage. The major type of the obtained AKOP was phosphatidylcholine, and the total contents of the DHA and EPA were 29.31%. AKOP liposome was almost completely digested in the small intestine in 1 h and the hydrolysis products could be quickly absorbed by intestinal enterocytes. The DHA in serum peaked at 2 h after administration of AKOP liposome. AKOP liposome could be quickly digested and absorbed in vivo. The obtained results might provide a scientific basis for the molecular mechanism analysis related to distinct bioactivities of Antarctic krill oil phospholipid.