The gut microbiota is an indispensable symbiotic entity within the human holobiont, serving as a critical regulator of host lipid metabolism homeostasis. Therefore, it has emerged as a central subject of research in the pathophysiology of metabolic disorders. This microbial consortium orchestrates key aspects of host lipid dynamics-including absorption, metabolism, and storage-through multifaceted mechanisms such as the enzymatic processing of dietary polysaccharides, the facilitation of long-chain fatty acid uptake by intestinal epithelial cells (IECs), and the bidirectional modulation of adipose tissue functionality. Mounting evidence underscores that gut microbiota-derived metabolites not only directly mediate canonical lipid metabolic pathways but also interface with host immune pathways, epigenetic machinery, and circadian regulatory systems, thereby establishing an intricate crosstalk that coordinates systemic metabolic outputs. Perturbations in microbial composition (dysbiosis) drive pathological disruptions to lipid homeostasis, serving as a pathogenic driver for conditions such as obesity, hyperlipidemia, and non-alcoholic fatty liver disease (NAFLD). This review systematically examines the emerging mechanistic insights into the gut microbiota-mediated regulation of intestinal lipid metabolism, while it elucidates its translational implications for understanding metabolic disease pathogenesis and developing targeted therapies.
Humans ; Gastrointestinal Microbiome/physiology* ; Lipid Metabolism ; Animals ; Intestinal Mucosa/metabolism* ; Homeostasis ; Dysbiosis ; Obesity/metabolism* ; Intestines/microbiology* ; Non-alcoholic Fatty Liver Disease/metabolism* ; Metabolic Diseases/metabolism*

OBJECTIVE: To investigate the characterization of the salivary microbiome in people with obesity and the differences in microbial composition, gene function and metabolic pathways of salivary microbiome between people with obesity and normal weight controls. METHODS: The study was carried out in people with obesity and age- and sex-matched normal weight controls. None of these selected participants had the systemic disease, oral mucosal disease or periodontal disease. Unstimulated saliva samples were collected and oral examination was conducted. DNAs from saliva samples were extracted and sequenced in an Illumina NextSeq 500 platform. Community composition, linear discriminant analysis of taxonomic differences,gene prediction, gene set construction and annotation of gene function were performed. RESULTS: The classified bacterial reads of the samples were 2 630 428 for each sample. A total of 11 phyla, 19 classes, 26 orders, 41 families, 62 genera and 164 species were detected ultimately. All samples had the same predominant phyla (Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria and Fusobacteria). There were statistical differences between the groups at the class, order, family, genus and species levels. At the class level, Negativicutes and Erysipelotrichia were more abundant in the obesity group, while Flavobacteriia and Bateroidetes dominated in normal weight group (P<0.05). At the species level, 16 showed significant differences in relative abundance among the groups, in which Prevotella melaninogenica,Prevotella salivae,Solobacterium moorei and Atopobium parvulum ware more abundant in the obesity group, whereas Streptococcus sanguinis dominated in normal weight group (P<0.05). The people with obesity had a higher number of salivary microbial genes (P<0.05). We produced statistics on gene prediction and found salivary microbiome of obesity group had a higher number of genes (P < 0.05). Genes associated with the pathways of metabolism and environmental information processing and human diseases were significantly enriched in the saliva samples of people with obesity (P < 0.01). CONCLUSION Significant differences were seen in composition, gene function and metabolic pathways of salivary microbiome between people with obesity and normal weight people. We hope to go on further study with larger sample size in the near future.
Bacteria/isolation & purification* ; Female ; Humans ; Male ; Microbiota ; Obesity/microbiology* ; Pilot Projects ; RNA, Ribosomal, 16S ; Saliva/microbiology*

Animals ; Gastrointestinal Microbiome ; Gastrointestinal Tract ; microbiology ; Humans ; Obesity ; microbiology ; pathology ; therapy

In recent years, more and more studies have noted the close association between gut microbiota and the development and progression of obesity. Gut microbiota may act on obesity by increasing energy intake, affecting the secretion of intestinal hormones, inducing chronic systemic inflammation, and producing insulin resistance. This article reviews the association between childhood obesity and gut microbiota, as well as possible mechanisms, in an attempt to provide a reference for the etiology, prevention and treatment of childhood obesity.
Animals ; Energy Metabolism ; Gastrointestinal Microbiome ; Glucagon-Like Peptide 2 ; physiology ; Humans ; Insulin Resistance ; Obesity ; etiology ; microbiology ; prevention & control

OBJECTIVETo investigate the effect of intermittent fasting on metabolize and gut microbiota in obese presenium rats fed with high-fat-sugar-diet.

METHODSWe fed the Wistar rats with high-fat and high-sugar diet to induce adiposity, and the rats for intermittent fasting were selected base on their body weight. The rats were subjected to fasting for 72 h every 2 weeks for 18 weeks. OGTT test was performed and fasting blood samples and fecal samples were collected for measurement of TC, TG, HDL-C and LDL-C and sequence analysis of fecal 16S rRNA V4 tags using Illumina. Gut microbial community structure was analyzed with QIIME and LEfSe.

RESULTSAfter the intervention, the body weight of the fasting rats was significantly lower than that in high-fat diet group (P<0.01). OGTT results suggested impairment of sugar tolerance in the fasting group, which showed a significantly larger AUC than compared with the high-fat diet group (P<0.05). Intermittent fasting significantly reduced blood HDL-C and LDL-C levels (P<0.05) and partially restored liver steatosis, and improved the gut microbiota by increasing the abundance of YS2, RF32 and Helicobacteraceae and reducing Lactobacillus, Roseburia, Erysipelotrichaceae and Ralstonia. Bradyrhizobiaceae was found to be positively correlated with CHOL and HDL-C, and RF39 was inversely correlated with the weight of the rats.

CONCLUSIONIntermittent fasting can decrease the body weight and blood lipid levels and restore normal gut microbiota but can cause impairment of glucose metabolism in obese presenium rats.

Animals ; Body Weight ; Diet, High-Fat ; Fasting ; Fatty Liver ; microbiology ; physiopathology ; Gastrointestinal Microbiome ; Lipids ; blood ; Obesity ; microbiology ; physiopathology ; RNA, Ribosomal, 16S ; Rats ; Rats, Wistar

For understanding the effect of MDG-1, a water-soluble β-D-fructan polysaccharide from Ophiopogon japonicas, on intestinal microecological balance, especially on the changes of lactobacillus, sixty 8-week-old male C57BL/6J mice were given a high-fat diet for six weeks and were also gavaged with saline once a day simultaneously. Then the mice which is below 30 grams or dropped more than 10% through lavage were eliminated and the rest were randomly divided into four groups: diet-induced obese (DIO) model group (n = 12, gavaged with saline), low-dose MDG-1 group (n = 12, gavaged with MDG-1, 75 mg · kg(-1)) , medial-dose MDG- 1 group (n = 12, gavaged with 150 mg · kg(-1)), and high-dose MDG-1 group (n = 12, gavaged with 300 mg · kg(-1)) according to the weight and blood glucose; the model group and MDG-1 group were placed on a high-fat diet while the normal control group (n = 12, gavaged with saline) were kept on a low-fat diet through the experiment. After 12-weeks of treatment, feces samples were collected and cultured for intestinal microecological balance analysis. Then the intestinal probiotics were cultured through traditional methods combined with modified gradient gel electrophoresis (DGGE) method. The changes of lactobacillus in each treatment group were also detected by a statistical analysis of the total number of the intestinal flora. We have established the phylogenetic tree by 16S rDNA sequencing and use some molecular identification methods such as PCR-DGGE to analyse the changes of the dominant bacteria floras, and also get the pure culture. In conclusion, different concentrations of MDG-1 can increase the number of the intestinal probiotics, especially Taiwan lactobacillus and Lactobacillus murinus, and improve their diversity and promote proliferation in a dose-dependent way.
Animals ; Biodiversity ; Diet, High-Fat ; adverse effects ; Dietary Carbohydrates ; administration & dosage ; analysis ; Humans ; Intestines ; drug effects ; metabolism ; microbiology ; Lactobacillus ; classification ; drug effects ; genetics ; growth & development ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Obese ; Molecular Structure ; Obesity ; drug therapy ; metabolism ; microbiology ; Ophiopogon ; chemistry ; Phylogeny ; Plant Extracts ; administration & dosage ; chemistry ; Polysaccharides ; administration & dosage ; chemistry

Overweight or obesity has become a serious public health problem in the world, scientists are concentrating their efforts on exploring novel ways to treat obesity. Nowadays, the availabilities of bariatric surgery and pharmacotherapy have enhanced obesity treatment, but it should has support from diet, physical exercise and lifestyle modification, especially the functional food. Resistant starch, an indigestible starch, has been studied for years for its beneficial effects on regulating blood glucose level and lipid metabolism. The aim of this review is to summarize the effect of resistant starch on weight loss and the possible mechanisms. According to numerous previous studies it could be concluded that resistant starch can reduce fat accumulation, enhance insulin sensitivity, regulate blood glucose level and lipid metabolism. Recent investigations have focused on the possible associations between resistant starch and incretins as well as gut microbiota. Resistant starch seems to be a promising dietary fiber for the prevention or treatment of obesity and its related diseases.
Dietary Carbohydrates ; metabolism ; Dietary Fiber ; metabolism ; therapeutic use ; Gastrointestinal Tract ; microbiology ; physiology ; Microbiota ; Obesity ; diet therapy ; prevention & control ; Starch ; metabolism ; Weight Loss

Animals ; Bacterial Translocation ; Fecal Microbiota Transplantation ; Gastrointestinal Microbiome ; Humans ; Insulin Resistance ; Obesity ; microbiology ; therapy ; Probiotics ; therapeutic use

OBJECTIVETo investigate the efficacy mechanisme of chicory extract interventing abdominal obesity rat from the aspect of gut bacteria.

METHODMale SD rats were randomly divided into five groups, namely the normal group, model group, large and small dose group of chicory and the fenofibrate group. Normal group was given deionized water, the other group was given fructose water and give the medical treatment of chicory and fenofibrate. Assay triglycerides, total cholesterol, LDL and HDL by biochemical methods and measure body weight and abdominal circumference and microscopicly observe the count changes of gut bacteria through real-time PCR method.

RESULTCompared with normal group, the triglyceride level and abdominal circumference were significantly higher (P < 0.05), weight and high-density lipoprotein increased but no significant changes and E. coli, lactobacillus increased significantly. Compared with model group, chicory extract large and small dose group and the fenofibrate group can significantly reduce triglyceride levels (P < 0.05), reduce the number of E. coli and Lactobacillus and increase the number of bifidobacteria. The fenofibrate group can significantly reduce total cholesterol and high-density lipoprotein levels.

CONCLUSIONThe chicory's treatment effect on abdominal obesity is significant. The efficacy mechanisme intervention abdominal obesity may be related to the reduction of the number of lactic acid bacteria and E. coli and the increase of bifidobacteria.

Animals ; Bacteria ; classification ; genetics ; isolation & purification ; Biodiversity ; Chicory ; chemistry ; metabolism ; Cholesterol ; metabolism ; Gastrointestinal Tract ; microbiology ; Humans ; Male ; Microbiota ; Obesity, Abdominal ; metabolism ; microbiology ; Plant Extracts ; metabolism ; Rats ; Rats, Sprague-Dawley ; Triglycerides ; metabolism

Bacteria ; genetics ; isolation & purification ; Bacterial Physiological Phenomena ; Bacteroidetes ; genetics ; isolation & purification ; Body Mass Index ; Body Weight ; Child ; Energy Metabolism ; Humans ; Infant ; Intestines ; metabolism ; microbiology ; Lactobacillus ; Obesity ; etiology ; metabolism ; prevention & control ; Probiotics ; therapeutic use ; Risk Factors