The gut microbiota seems to play a role in the development and progression of obesity. The human body contains staggering numbers of microbes, including thousands of bacterial species, in addition to many eukaryotes, achaea, protists, and viruses, which collectively contain an estimated 5 million genes that have profound metabolic and immunomodulatory effects upon the mammalian host 8. Prebiotics reduce body fat and alter intestinal microbiota in. Gut microbiota can influence energy extraction from food, lipid metabolism, immune response and endocrine functions and its profile has shown to differs between obese. Mass reproduce only with permission from mayo clinic proceedings. Particularly, the use of germfree animals and microbiota transplant showed that the gut microbiota may play a causal role in the development of obesity and associated metabolic disorders, and lead to identification of several mechanisms. Gut dysbiosis was identified in overweight and moderate obesity,4 5 as evidenced by substantial. Potential therapies to alter the gut microbiota to treat obesity include dietary changes, supplementation of the diet with probiotic organisms and prebiotic compounds that influence bacterial growth, and the use of faecal microbiota transplant, in which gut microbiota from healthy individuals are introduced into the gut. A role for probiotics ludovico abenavoli 1, emidio scarpellini 2, carmela colica 3, luigi boccuto 4,5, bahare salehi 6, javad shari. The gut microbiota is considered as one of the relevant contributors involved in the complex causes of obesity and related metabolic disorders. The connection between gut microbiota and energy homeostasis and in. As early as the 1980s, the gut microbiota has been associated with obesity in human 19 and rats 20 by utilizing culturedependent methods, which only sees pieces of microbes in the gut. Gut microbiota is the most complex ecosystem in nature since it harbors large bacterial populations in the intestine and colon, with around 10111012 microorganismsgram of the intestinal content and mostly are anaerobes 95% of the total organisms 12. It is sensitive to dietary changes and able to alter composition within hours in both animals and humans 25.
Human gut microbiota associated with obesity in chinese. Animal studies as well as proof of concept studies using fecal transplantation demonstrate the pivotal role of the gut. Gut microbiota and obesity 2278 diabetes care, volume 33, number 10, october 2010 care. Gut microbiota, prebiotics, probiotics and synbiotics in management of obesity and prediabetes. Prebiotics reduce body fat and alter intestinal microbiota. Dietary fiber has been shown to prevent highfat diet induced obesity through modulating the gut microbiota.
Current thinking considers a potential role of gut microbiota on the development of obesity and its related comorbidities. Therefore, the gut microbiome has been suggested as a driving force in the pathogenesis of obesity. These findings raise the possibility that the gut microbiota has an important role in regulating weight and may be partly responsible for the development of obesity in. Research from the last 30 years has clarified the role of the imbalance between energy intake and expenditure, unhealthy lifestyle, and genetic variability in the development of obesity. Impact of the gut microbiota on inflammation, obesity, and metabolic disease claire l.
May 03, 2018 impact of gut microbiota on local and distant organs contributes to obesity development and progression. Gut microbiota and obesity british society for immunology. Nowadays, obesity is one of the most prevalent human health problems. The number of bacterial cells in an adult human body is ten times more than the cells constituting the human body. Lactose digestion lipid metabolism oxalate metabolism composition and metabolic markers of the gut microbiota xenobiotics, phytochemicals indigestible dietary components metabolic activity of gastrointestinal mucosa and liver ibd and ibs inflammatory bowel diseases.
Development of obesity correlates with a shift in the abundance of the 2 dominating divisions, the bacteroidetes and the firmicutes. Here, we show that the hepatic translocation of obesity induced lipoteichoic acid. Research about obesity and the gut microbiota has been dominated by studies focused on nhws e. The proposed mechanisms by which the microbiome may contribute to the development of obesity include. Jun, 2018 gut microbiota dysbiosis probably promotes diet induced obesity and metabolic complications by a variety of mechanisms including immune dysregulation, altered energy regulation, altered gut hormone regulation, and proinflammatory mechanisms such as lipopolysaccharide endotoxins crossing the gut barrier and entering the portal circulation29 30. Diet and obesity diet shapes the gut microbiota before addressing the involvement of the gut microbiota towards shaping obesity and associated metabolic disorders, it is appropriate to.
In local tissues, obesity associated gut microbiota have an increased capacity to harvest energy from the diet, stimulate gene. Its role in diabetes and obesity nutrients 2015, 7, 91719184 nutrients 2015, 7, pagepage 7 5. Mouse models are far from perfect for deciphering the relationship between diet, gut microbiota, and human obesity, and although alteration of the gut microbiota using antibiotics has been shown to markedly influence obesity and insulin resistance in mice 22, 23, it resulted in limited effects in humans. Jeffrey gordon at the washington university school of medicine showed that obese and lean human twins have clear differences in their gut. The obesity epidemic is globally considered as one of the topmost health concern whose multifactorial etiology. The global obesity epidemic has necessitated the search for better intervention strategies including the exploitation of the health benefits of some gut microbiota and their metabolic products. Each individual has a unique gut microbiota composition, but gut microbiota mainly belongs to four phyla, firmicutes, bacteroidetes, actinobacteria and proteobacteria. Nutrients free fulltext gut microbiota and obesity. We evaluated the 16s rrna gene, the enterotypes, and quantity of the gut microbiota among obese children and the control cohort and learned the differences of the gut microbiota. The correlation between host, microbiota, and diet is very complicated, but the procedures involved are well connected. Consumption of prebiotics, which are nondigestible food ingredients utilized by gut microorganisms and. Pediatric obesity remains a public health burden and continues to increase in prevalence. Research from the last 30 years has clarified the role of the imbalance between energy intake and expenditure, unhealthy lifestyle, and genetic variability in the development of.
Although several molecular pathways have widened the view on the causative association between gut microbiota alterations and obesity development, this linkage remains very complex. Obesity is a worldwide epidemiologic syndrome characterized by fat mass accumulation, mainly visceral fat. The gut microbiota has been linked with chronic diseases such as obesity in humans. Recent studies have shown that gut microbiota may influence liver diseases by transferring its metabolites and components. Bamboo shoot fiber prevents obesity in mice by modulating. In the 1990s, the application of cultureindependent molecular techniques based on 16s ribosomal rna rrna genes e. On a global scale, projection estimations have predicted that the obesity epidemic rose from 400 million obese adults in 2005 to 700 million in 2015, a trend that is set to continue towards 2030. Effects from dietinduced gut microbiota dysbiosis and. Particularly, the use of germfree animals and microbiota transplant showed that the gut microbiota may play a causal role in the development of obesity and associated metabolic disorders, and. Gut microbiota and obesity experimental models have revealed several mechanisms connecting the gut microbiota to obesity and metabolic disorders.
Early life antibiotic exposure linked to increased risk of. Most studies of overweight and obese people show a dysbiosis characterised by a lower diversity. The contribution of the gut microbiota to the development. The relationship between diet, gut microbiota, and energy homeostasis was further investigated in models of dietinduced obesity 4,5, e. Also it will be briefly presented some measures to combat obesity, including those that. The western diet increased the relative abundance of. The debate on the significance of the correlation between gut microbiota imbalance and obesity is one of the hottest topics in medicine. The connection between gut microbiota and energy homeostasis and inflammation and its role in the pathogenesis of obesity related disorders are increasingly recognized. Role of the gut microbiome in the pathogenesis of obesity and. Studies in mice have associated the phylum firmicutes with obesity and the phylum bacteroidetes with weight loss. Proposed mechanisms linking the microbiota to fat content and weight include.
Maternal gut microbiota in pregnancy influences offspring. Additionally, changes in the gut microbiota composition and permeability that have been highly documented in obesity 678 9, were also found to play a role in obesity related inflammation. More recently, the composition and metabolic functions of gut microbiota have been proposed as being able to affect obesity development. The gut microbiota plays a causal role in obesity and is a promising therapeutic target. Shortchain fatty acid production by gut microbiota from. There is also a growing body of evidence relating the gut microbiome composition to insulin resistance. Obesity increases the risk of cancers, including hepatocellular carcinomas hcc. Profiles of gut microbiota in children with obesity from.
Although the human microbiome has fantastic potential, it has. The gut microbiota of children with obesity and normal. Request pdf gut microbiota, obesity and diabetes the central role of the intestinal microbiota in the progression and, equally, prevention of metabolic dysfunction is becoming abundantly. We evaluated the 16s rrna gene, the enterotypes, and quantity of the gut microbiota among obese children and the control cohort and learned the differences of the gut microbiota during the. The composition of the gut microbiota has received attention as an etiological factor in the development of obesity. While several studies have reported gut microbiota composition differences associated with. Starting with the observation that offspring of germfree mice tended to become obese on highfat diets, kimura et al. The obese microbiota transfer resulted in mice with a greater increase in total body fat and clearly identified the gut microbiota as a contributing factor in the obesity story. Obesity and its comorbidities are currently considered an epidemic, and the involved pathophysiology is well studied. Pdf gut microbiota and the development of obesity edi.
Gut microbiome in obesity, metabolic syndrome, and. In individuals with obesity, changes in the composition of the gut microbiota occur not only at the level of phyla but also at the level of genera or species. Evidence, mostly from studies of rodents, suggests that the gut microbiota may play a role in the development of obesity. Obesity, metabolic syndrome, and type 2 diabetes are major public health. Oct 12, 2015 the influence of the gut microbiota in human health and disease has been revealed in the recent years.
It is widely accepted that the healthy gut microbiotais essential for host homeostasis and immunostasis, harboring an enormous number and variety of microorganisms and genes tailored by hundreds of exogenous and intrinsic host factors. Molecular mechanisms in t1d to explain the pathways and the impact of t1d. Gut microbiota can influence energy extraction from food, lipid metabolism, immune response and endocrine functions and its profile has shown to differs between obese and lean subjects. Obese patients have a lesser diversity and richness in the bacterial component of gut microbiota than eutrophic subjects 25, 26, 27. Specifically, conventionalization the restoration of conventional intestinal flora of germfree. Imbalances in the gut microbiota, the bacteria that inhabit the intestines, are central to the pathogenesis of obesity. The colonic microbiome is the most diverse and also the best characterized microbial community. To investigate the gut microbiota differences of obese children compared with the control healthy cohort to result in further understanding of the mechanism of obesity development.
Nicholson1,2 and marcemmanuel dumas2 abstract the human gut harbors more than 100 trillion microbial cells, which have an essential role in human metabolic. Pdf the distal gut harbours microbial communities that outnumber our own eukaryotic cells. Nov 07, 2019 the debate on the significance of the correlation between gut microbiota imbalance and obesity is one of the hottest topics in medicine. Gut microbiota, obesity and diabetes postgraduate medical.
Izzo 9 and ra aele capasso 11, 1 department of health sciences, university magna graecia, campus salvatore venuta. Meanwhile, a large amount of recent research has convincingly demonstrated that the stability and diversification of gut microbia is essential for the. Human gut microbiota in obesity and after gastric bypass. Jci gut microbiome, obesity, and metabolic dysfunction. Obesity is a major public health issue as it is causally related to several chronic disorders, including type2 diabetes, cvd and cancer. Impact of the gut microbiota on inflammation, obesity, and. Obesity is a disease with a complex etiology and variable prevalence across different populations. The changes in gut microbiota associated with obesity are summarised in table. Immune system the immune system also seems to be important in the selection of the gut microbiota. Signals from gut microbiota to local tissue signals from gut microbiota to distant organs glp1 pyy cck figure 1.
As for the bacterial groups in play, comparing the gut microbiota of obese and lean people revealed higher firmicutes and. Genetic and dietinduced obesity are associated with alterations of i the composition and ii the functional properties of the gut microbiota. Additionally, obesity is associated with low gut microbiota diversity, and it may alter the composition of certain bacteria in humans and animal models 9. Insights into the role of gut microbiota in obesity. Among the established human gut microbiota which are mostly grampositive and anaerobic. The gut microbiota impact on host functions through several mechanisms, suggesting that they might involve in the onset of obesity. Review open access impact of the gut microbiota on inflammation, obesity, and metabolic disease claire l. Selecting hostadapted gut microbiota various components influence the microbial ecology of the gut figure 1. In local tissues, obesity associated gut microbiota have an increased capacity to harvest energy from the diet, stimulate gene reprogramming in the colon, change polypeptide hormones and other bioactive molecules released by ec cells, decrease the intestinal barrier, and disturb immune. Role of the gut microbiota in nutrition and health the bmj. Gut microbiota is a group of microorganisms that reside in the gastrointestinal tracts of humans and animals. Studies in germfree mice revealed that the gut microbiota enhances adiposity mainly by increased energy extraction from food and by regulating fat storage 16, 39, and germfree mice are protected from obesity and metabolic syndrome 16, 17, 40. However, the precise molecular mechanisms through which obesity promotes hcc development are still unclear. A mouse model has shown that methanobrevibacter smithii, the predominant archaeon in the human gut, enhanced shortchain fatty acid scfa production by fermentative bacteria by removing h 2 and formate 3.
Boulange1, ana luisa neves2, julien chilloux2, jeremy k. Role of the gut microbiota in defining human health. Linking gut microbiota and inflammation to obesity and. Mice that are colonized with a specific known bacteria are termed gnotobiotic or known life and can help us understand the role of specific bacteria in inflammation and disease course 24. Pdf obesity is a worldwide epidemiologic syndrome characterized by fat mass accumulation, mainly visceral fat. Animals models of obesity connect an altered microbiota composition to the development of obesity, insulin resis. Pdf on oct 1, 2019, haewon kim and others published the role of the gut microbiota in obesity find, read and cite all the research you need on researchgate. Gut microbiota from twins discordant for obesity modulates. Gut microbiota and its possible relationship with obesity.
Gut microbiota dysbiosis may lead to a number of diseases, including gastrointestinal disorders, obesity, cardiovascular diseases, allergy and central nervous systemrelated diseases. Gut microbiota phenotypes of obesity npj biofilms and. Gut microbiota promotes obesityassociated liver cancer. Novel research shows that the gut microbiota is involved in obesity and metabolic disorders, revealing that obese animal and human subjects have alterations in the composition of the gut microbiota compared to their lean counterparts. Oct 18, 2018 obesity and diabetes are worldwide epidemics. Animals models of obesity connect an altered microbiota composition to the development of obesity, insulin resistance, and diabetes in the host through several mechanisms. Pdf gut microbiota and the development of obesity edi val. There is also accumulating evidence that suggests colonization of the gut microbiota at an early age plays a pivotal role in the weight gain and development of obesity in the later life between. Transplantation of the gut microbiota from obese do. Obesity and metabolic diseases tend to go together, and humans who become obese are also prone to type 2 diabetes and cardiovascular problems. There is there is evidence for the association between gut bacteria and obesity both in infancy and in adults.
Rodney berg, of louisiana state universitys microbiology and immunology department, wrote about. Specifically, the microbial production of shortchain fatty acids scfa from the fermentation of otherwise indigestible dietary carbohydrates may protect against pediatric obesity and metabolic syndrome. Gut microbiota and obesity clinical nutrition experimental. Scientific interest in the potential causative role of the gut microbiota in obesity was attracted by the demonstration that a distinctive gut microbiota composition prevails in obese individuals, with adjustments following weight gain or weight loss 16. The gut microbiota used to be called the microflora of the gut.
Hypercaloric diets are tightly related to the obesity etiology and also cause alterations in gut microbiota functionality. The gut microbiota as an environmental factor that regulates fat storage. The experiment remodeled gut microbiome in the fxrnull and wildtype mice demonstrated that the microbiota promotes dietinduced obesity through fxr signaling. Impact of gut microbiota on local and distant organs contributes to obesity development and progression. Obesity, diabetes, and gut microbiota diabetes care. Diet and antibiotics are known to play crucial roles in changes in the microbiota ecosystem and the disruption of its balance.