Study Improing Effect Of Fucans Isolated From Sea Cucumbers On The Type2Diabetes And Tumor Metastasis Mice

Sea cucumber, an important food and medicine resource, has lots of bioactivesubstances, such as collagen proteins, saponins, sea cucumber polysaccharide andpolypeptide. And the sea cucumber polysaccharide is one of the most importantbioactive substances. There are the sulfated fucoidan (SC-FUC) and sea cucumberchondroitin sulfate (SC-CHS) of the sea cucumber polysaccharide. SC-FUCcomposed chiefly of fucose and sulfate, an object of simple construction. In this study,sea cucumber fucoidans (SC-FUC) were isolated from the Cucumaria frondosa,Thelenata anax and Acaudina molpadioidea, the composition of monosaccharide hasbeen identified by acid hydrolysis and HPLC analysis. Together with fucoidanextracted from Laminaria japonica Aresch, this paper is to explore the ameliorativeeffect and mechanism of SC-FUC on insulin resistance and glucose metabolism onthe type2diabetes mice; What’s more, their anti-tumor and anti-metastasis effect wasstudied in animal models. Results are shown as follows:The monosaccharide composition of the SC-FUC was simple and almostcomposed chiefly of fucose, mainly with molar ratio0.1:1:0.3:0.17,0.26:1:0.15:0.21and0.02：1：0.04：0.02of glucuronic acid (GlcUA), fucose (Fuc), galactose(Gal)and galactosamine (GlaN) in fucoidans isolated from Cucumaria frondosa, Thelenataanax and Acaudina molpadioidea. Type2diabetes mouse models were establishmentwith long high fat diets, and all mice were sacrificed after75days. The three kinds ofSC-FUC could significantly reduce weight gain (P<0.01), fasting blood insulin andglucose levels, which was high in type2diabetes mice. They have significant effectof easing obesity in mice with impaired glucose tolerance and increased muscle andliver glycogen accumulation. It also could decrease serum and liver lipid levels(P<0.05). Detected with RT-PCR, it was find out that SC-FUC could promote IR、 PI3K、AKT2mRNA expression and decreased GSK3β mRNA expression inmuscle and liver. It can suggest that SC-FUC could improve the glycogenaccumulation. And it could increase serum levels of adiponectin and promoteGLUT4mRNA expression in adipose and muscle tissue of mice also (P<0.05).Fucoidan from sea cucumber can significantly reduce blood glucose levels and lipidaccumulation, improve insulin resistance and it improved glucose transporters andglucose metabolism the target organs of insulin.The Lewis lung carcinoma models of C57BL/6mice were established and theresults showed that the tumor growth was suppressed significantly in SC-FUC groups.The metastatic colonies occurrence rate of SC-FUC groups was lower than controlgroup, and the difference were significant (P<0.05). SC-FUC could significantlydown-regulated the expression levels of HIF-1α、b-FGF and VEGF mRNA of thetumor than control. They could down-regulated the expression levels of MMP2/9andHpa mRNA also. The results suggested SC-FUC has inhibitory effect on growth andmetastasis of Lewis lung carcinoma cell in mice, and may be through inhibiting solidtumor angiogenesis and invasive potential of cancer cells.To observe the inhibitory effect of SC-FUC on lung metastasis of mousemelanoma cell line B16-F10. The results suggested that SC-FUC clearly suppressedlung metastasis in mice and could reduce the levels of serum saliva acid content andγ-GT energy clearly. Biochemical parameters such as hydroxyproline, hexosaminesand uronic acid levels in the lung were also reduced clearly in the SC-FUC treatedanimals. Therefore, the results indicate that SC-FUC can inhibit the metastasis ofB16-F10metastatic mouse melanoma cells and its mechanism is maybe that it caninhibit the B16-F10cells adhering to the ECM and reduce the migration ability ofB16-F10cells.In this study, we systemically investigated the improing effect on the type2diabetes and anti-metastasis effect of fucoidan; furthermore we do lots of work to dothat contribute to the illustration of the mechanism of its effect. Our works provide the scientific improvements for the research of the bioactive function of the sea cucumberpolysaccharide and good use in food and medicine.