Protective Effect Of Dietary Fiber From Bamboo Shoots On Lipid Metabolism In High-fat Diet-fed Mice

Bamboo shoots are a good source of dietary fiber,which can prevent obesity in mice,exhibiting better effects than various common dietary fibers,and can improve insulin resistance.However,the mechanism of bamboo shoot fiber in preventing obesity is not yet clear.Therefore,this article compares the effects of bamboo shoot dietary fiber and cellulose on lipid metabolism,as well as the effects of bamboo shoot dietary fiber with probiotics and cellulose with probiotics on lipid metabolism in high-fat diet mice,providing reference for the utilization of bamboo shoot dietary fiber.This study used a high fat diet containing 60% fat to induce obesity in C57BL/6J male mice.Dietary fiber in the high fat diet was replaced by an equal amount of 10% bamboo shoot dietary fiber.Probiotics were administered by gavage with an equal volume of bacterial solution.The animals were divided into 5 groups,namely the normal control group(CL),high fat group(HFC),bamboo shoot fiber group(HFF),high fat probiotics group(HFCB),and bamboo shoot fiber probiotics group(HFFB).The animals were fed for 12 weeks and weighed every week.The contents of total cholesterol(TC),triglyceride(TG),low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C)in serum were measured at 0,4,8 and 12 weeks.After 12-week feeding,fasting blood glucose levels were measured,while livers,adipose tissues,bloods,and cecal contents were collected.After liver and adipose tissue fixation,HE staining was performed to observe structural changes.Cecum contents were used for 16 S r DNA sequencing and analysis of intestinal flora;colon feces were used in quantitative analysis of short chain fatty acids;the overall changes of genes related to liver lipid metabolism were determined by transcriptome sequencing using liver tissues.The experimental results showed that,compared with the CL group,mice in the HFC group had a significant increase in body weight.Compared with the HFC group,the HFCB group showed a decreasing trend in body weight.Mice in both the HFF group and HFFB group showed significantly reduced in the weight gain of mice,but there was no significant difference between this two groups.Compared with the HFC group,mice in the HFCB group,HFF group and HFFB group showed significantly reduced fasting blood glucose,total cholesterol,LDL-C,and HDL-C levels,reduced liver fat infiltration,and improved adipocyte enlargement.Between the HFF group and the HHFB group,the blood glucose levels in the HFF group were significantly lower than those in the HFFB group,and there was no significant difference in body weight,blood lipids,and lipid accumulation.The results of microbial diversity sequencing showed that,compared with the HFC group,the diversity of gut microbiota in the HFF and HFFB groups increased,and the richness of specific microbiota increased.At the phylum level,the relative abundance of Firmicutes,Actinobacteriota,and Bacteroidota increased.At a subordinate level,the intake of dietary fiber from bamboo shoots can reduce the incidence of Faecalibaculum and unclassified bacteria＿f＿The abundance of Lachnospiraceae and Blautia increased Lachnospiraceae＿NK4A136＿The relative abundance of group,Lachnoclostridium,and Desulfovibrio can increase the growth of Lactobacillus in combination with probiotics.In addition,the effect of dietary fiber from bamboo shoots on body weight,blood lipids,and gut microbiota in high-fat diet mice is greater than that of probiotics.Therefore,fecal short chain fatty acids and liver transcriptome were analyzed only in the CL,HFC and HFF groups.The results showed that compared with HFC,HFF diet significantly increased the content of acetic acid,butyric acid,isovaleric acid and total short chain fatty acids,which may be a way to inhibit lipid accumulation.The increase of short chain fat is related to Clostridium,Spirillaceae and anaerobes.Bamboo shoot dietary fiber stays in the intestine for a long time,producing rich short chain fatty acids to regulate the balance of intestinal microbiota,which may partially regulate intestinal microbiota by increasing fecal volume and transport time.The results of mouse liver transcriptome showed that there were 6951 differential genes(3192 up-regulated genes and 3759 down regulated genes)in HFC group and HFF group,including 149 genes related to lipid metabolism(99 up-regulated genes and 50 down regulated genes),which were enriched in 15 signal pathways,indicating that bamboo shoot dietary fiber had a significant impact on lipid metabolism genes.Through the above analysis,it has been clarified that bamboo shoot dietary fiber and bamboo shoot dietary fiber with probiotics regulate the intestinal microbiota,increase the production of short chain fatty acids,and regulate gene expressions involve in lipid metabolism,ultimately improving the lipid metabolism in mice.This article only focuses on obesity and the metabolic differential genes caused by obesity.The potential physiological effects of dietary fiber from bamboo shoots in the future can be considered from multiple perspectives.China has abundant bamboo resources,and this study is beneficial for the better development and utilization of bamboo shoot resources in China,promoting human health,helping farmers in mountainous areas to lift themselves out of poverty and become prosperous,and playing a beneficial role in promoting the Yunnan plateau characteristic agricultural economy.