The Effect Of Fucoidan On Blood Glucose Regulation And Intestinal Flora Repairment In Hyperglycemic Mice

The problem of hyperglycemia,hypertension and hyperlipidemia" has been gradually prominent in recent years,with the improvement of people’s living standards and the change in lifestyle,especially the number of diabetes patients is rising year by year.Studies have shown that hyperglycemia is a developmental process from quantitative to qualitative changes in diabetes.A significant way of avoiding the incidence of diabetes is to recognize factors closely linked to the development of hyperglycemia and to pursue targeted early intervention.The imbalance of intestinal flora and the incidence and growth of hyperglycemia have gained more and more interest in the academic community,among several related variables.Imbalanced intestinal flora can lead to a decrease in beneficial bacteria and an abnormal increase in harmful bacteria,leading to abnormal metabolism of glucose and lipids in the human body and causing low-grade chronic inflammation in the body.A new concept for the prevention and intervention of hyperglycemia is expected to be among the various strategies for the prevention and treatment of hyperglycemia,taking intestinal flora as the target and promoting the recovery of healthy intestinal flora and controlling blood glucose through appropriate adjustment of dietary structure.Wakame is East Asia,as marine algae,people often consume health care,keeping Alginic sugar gum as the key functional components of wakame in good health food,in recent years,researchers have progressively attracted focus on functional foods.This experiment is interrelated with the control of immune function by contrasting the high and low two doses of fucoidan to hyperglycemic mice caused by STZ hypoglycemic effect and exploring its repair with intestinal flora.Objectives:It was determined that high and low doses of fucoidan had an interventional effect on hyperglycemia mice,which was mainly achieved by restoring intestinal flora balance and regulating immune function.Methods:1.Polysaccharides were extracted using a water extraction method and pre-purified polysaccharides were obtained by precipitation with 80% ethanol.Polysaccharides were prepared in high and low concentrations of fucoidan based on a dosage of 600 mg/kg and 200 mg/kg.2.Male BALB/c mice were injected intraperitoneally with 50 mg/kg STZ to develop a mouse model of hyperglycemia.The mice were randomly divided into a hyperglycemia model group,a high-dose recovery group of fucoidan(600 mg/kg*d)and a low-dose recovery group of fucoidan(200 mg/kg*d),and a normal control group was established.The number of mice in each group was 5.During the experiment,the body weight,blood glucose and oral glucose tolerance tests were measured.After 35 days of intragastrical administration,mice were sacrificed and serum,pancreas,liver andcolonwere stored for later use.3.The feces of mice were collected and total DNA was extracted for the preliminary analysis of PCR-DGGE flora structure.After the experimental effect was determined,high-throughput sequencing analysis of 16 Sr RNA was conducted to further compare the composition and abundance of intestinal flora of mice in each group.Pathological changes in pancreas,liverand intestinal mucosa have been observed with H&E staining.Immunohistochemistry was used to detect the expression of intestinal mucin and mucin secreted by goblet cells in the tissues of the colon in order to detect the integrity of the mechanical and chemical intestinal barriers.Blood lipid metabolism of mice has been detected by lipid-related indices.Cytokines in mice serum have been detected by q PCR and ELISA to assess the level of inflammation in mice.Results:1.In terms of blood glucose regulation,the high-dose recovery group of fucoidan effectively reduced random blood glucose in mice and improved glucose tolerance.The hypoglycemic effect of polysaccharide in low dose group was not obvious in high dose group.2.In terms of improving the effect of blood glucose complications,the high-dose recovery group of fucoidan reduced pathological changes and improved the pathological inflammationin the liver and pancreas,and improved blood lipids.The fucoidan low-dose recovery group also had moderate improvement in the above-mentioned aspects,but none of the fucoidan high-dose group had significant effects.3.Sequencing results of 16 S r RNA gene amplifiers have shown that the intestinal microflora structure of mice has been improved in both high and low-dose of the fucoidan recovery groups,and that beneficial butyric acid-producing bacteria such as Odoribacter,Roseburia,Coprococcus and Rikenella have been significantly enhanced.At the same time,the average relative abundance of various opportunistic pathogens,such as Psychrobacter,Coprobacillus,Aggregatibacter,etc.,decreased significantly in both recovery groups.In addition,intestinal inflammation decreased in the recovery group and the expression of mucin secreted by goblet cells and tight junction protein increased significantly in intestinal tissue.4.Serum levels of LPS,IL-6,and IL-1β pro-inflammatory cytokines in hyperglycemic mice decreased significantly after fucoidan gavage,and the effect of fucoidan high-dose recovery was better than that of fucosin low-dose recovery group.Conclusions:1.Fucoidan may reduce symptoms of hyperglycemia caused by STZ and may improve glucose and lipid metabolism disorders and inflammation of the liver tissues associated with hyperglycemia and may have a dose-responsive effect.2.Fucoidan intervention promoted the balance of intestinal flora,repaired mechanical and chemical intestinal barriers,and improved immune function of mice,suggesting that restoration of intestinal microecology may be the main reason for the reduction of blood glucose in mice.