A Review of the Relationship between Gut Microbiome and Obesity

Gut Microbes, 2012

obesity develops from a prolonged imbalance of energy intake and energy expenditure. However, the relatively recent discovery that the composition and function of the gut microbiota impacts on obesity has lead to an explosion of interest in what is now a distinct research field. Here, research relating to the links between the gut microbiota, diet and obesity will be reviewed under five major headings: (1) the gut microbiota of lean and obese animals, (2) the composition of the gut microbiota of lean and obese humans, (3) the impact of diet on the gut microbiota, (4) manipulating the gut microbiota and (5) the mechanisms by which the gut microbiota can impact on weight gain.

Digestive Diseases, 2012

The current obesity epidemic clearly has many causes, including the impact of our modern world on both our diet and our lifestyle/physical activity. Although many interventions have been recommended, the prevalence of obesity continues to rise and has forced a re-evaluation of the potential interventions that could have an impact. In recent years it has been definitively shown that microbiota in the gastrointestinal tract are altered in obese individuals. Recent data provide a potential mechanistic understanding of the interactions between microbiota and obesity and allow potential new interventions to the control of obesity to be proposed.

International Journal of Food Science and Nutrition, 2023

In today's society, obesity has become a major problem. It develops in healthy people as a result of genetic and environmental influences. Over the course of a year, this metabolic condition worsens. Recent research has made it clear that having a healthy gut flora reduces the complications associated with obesity. If people maintain a healthy lifestyle in addition to eating an adequate diet, their gut microbiome, a complex population, will be directly linked to eliminating all obesity symptoms. Different bacteria are urged to control obesity's symptoms. Probiotics such as Lactobacillus and Bifidobacterium have a direct impact on reducing obesity. The gut microbiota aids in digestion, controls hunger, reduces chronic inflammation, and regulates circadian rhythm. Therefore, the general gut microbiota directly influences the symptom of obesity. This review discusses the relationship between the gut microbiome and obesity.

Resumen Introducción: Los avances en herramientas para la investigación molecular han permitido una mayor com-prensión de cómo los microbios pueden influir en la fisio-logía del huésped. Un campo de investigación muy intere-sante que se ha llamado la atención recientemente es el posible papel de la microbiota intestinal en el desarrollo de la obesidad y de los trastornos metabólicos. Objetivos: El objetivo de esta revisión es discutir los mecanismos que explican la influencia de la microbiota intestinal en el metabolismo del huésped. Resultados y discusión: La microbiota intestinal es importante para la fisiología normal del huésped. Sin embargo, las diferencias en su composición pueden tener efectos diferentes sobre el metabolismo del huésped. Se ha demostrado que las personas obesas y delgadas tienen un perfil de composición diferente de la microbiota. Estas diferencias en la composición de la microbiota pueden contribuir a un desequilibrio de peso y alteración del metabolismo. Las evidencias de los modelos animales sugieren que es posible que la microbiota de los sujetos obesos tienen una mayor capacidad para captar energía de la dieta proporcionando sustratos que pueden activar las vías lipogénicas. Además, los microorganismos tam-bién pueden influir en la actividad de la lipoproteína lipasa lo que interfiere con la acumulación de triglicéri-dos en el tejido adiposo. La interacción de la microbiota intestinal con el sistema endocannabinoide proporciona una ruta a través del cual puede alterar la permeabilidad intestinal. Aumento de la permeabilidad intestinal per-mite la entrada de la circulación de endotoxinas, que están relacionados con la inducción de la inflamación y la resistencia a la insulina en los ratones. El impacto de los mecanismos propuestos para los seres humanos todavía necesita uma mayor investigación. Sin embargo, el hecho de que la microbiota intestinal puede ser modulada por componentes de la dieta refuerza la importancia de estu-diar cómo los ácidos grasos, hidratos de carbono, micro-nutrientes, prebióticos y probióticos pueden influir en la composición de la microbiota intestinal y el desarrollo de la obesidad. La microbiota intestinal parece ser un obje-tivo importante y prometedor en la prevención y el trata-miento de la obesidad y trastornos metabólicos relaciona-dos en la investigación futura y la práctica clínica. Abstract Introduction: Advances in tools for molecular investigations have allowed deeper understanding of how microbes can influence host physiology. A very interesting field of research that has gained attention recently is the possible role of gut microbiota in the development of obesity and metabolic disorders. Objective: The aim of this review is to discuss mechanisms that explain the influence of gut microbiota on host metabolism. Results and discussion: The gut microbiota is important for normal physiology of the host. However, differences in their composition may have different impacts on host metabolism. It has been shown that obese and lean subjects present different microbiota composition profile. These differences in microbiota composition may contribute to weight imbalance and impaired metabolism. The evidences from animal models suggest that it is possible that the microbiota of obese subjects has higher capacity to harvest energy from the diet providing substrates that can activate lipogenic pathways. In addition, microorganisms can also influence the activity of lipoprotein lipase interfering in the accumulation of triglycerides in the adipose tissue. The interaction of gut microbiota with the endocannabinoid system provides a route through which intestinal perme-ability can be altered. Increased intestinal permeability allows the entrance of endotoxins to the circulation, which are related to the induction of inflammation and insulin resistance in mice. The impact of the proposed mechanisms for humans still needs further investigations. However, the fact that gut microbiota can be modulated through dietary components highlights the importance to study how fatty acids, carbohydrates, micronutrients, prebiotics, and probiotics can influence gut microbiota composition and the management of obesity. Gut microbiota seems to be an important and promising target in the prevention and treatment of obesity and its related metabolic disturbances in future studies and in clinical practice.

Arquivos Brasileiros de Endocrinologia & Metabologia, 2009

Obesity is a pandemic which has been rapidly developing for three decades. When a population is submitted to the same nutritional stress, some individuals are less susceptible to dietinduced weight gain and hyperglycemia. This observation suggests that other mechanisms are involved which are not directly related to the human genome. The human gut contains an immense number of microorganisms, collectively known as the microbiota. Evidence that gut microbiota composition can differ between obese and lean humans has led to the speculation that gut microbiota can participate in the pathophysiology of obesity. Different mechanisms have been proposed to explain the link between gut flora and obesity. The first mechanism consists in the role of the gut microbiota to increase energy extraction from indigestible dietary polysaccharides. The second, consists in the role of gut flora to modulate plasma lipopolysaccharide levels which triggers chronic low-grade inflammation leading to obesity and diabetes. A third mechanism proposes that gut microbiota may induce regulation of host genes that modulate how energy is expended and stored. However, further studies are needed to clarify a number of issues related to the relationship between the gut microbiota and obesity. Arq Bras Endocrinol Metab. 2009;53(2):139-144.

Frontiers in Cellular and Infection Microbiology, 2016

Obesity, a global epidemic of the modern era, is a risk factor for cardiovascular diseases (CVD) and diabetes. The pervasiveness of obesity and overweight in both developed as well as developing populations is on the rise and placing a huge burden on health and economic resources. Consequently, research to control this emerging epidemic is of utmost importance. Recently, host interactions with their resident gut microbiota (GM) have been reported to be involved in the pathogenesis of many metabolic diseases, including obesity, diabetes, and CVD. Around 10 14 microorganisms reside within the lower human intestine and many of these 10 14 microorganisms have developed mutualistic or commensal associations with the host and actively involved in many physiological processes of the host. However, dysbiosis (altered gut microbial composition) with other predisposing genetic and environmental factors, may contribute to host metabolic disorders resulting in many ailments. Therefore, delineating the role of GM as a contributing factor to obesity is the main objective of this review. Obesity research, as a field is expanding rapidly due to major advances in nutrigenomics, metabolomics, RNA silencing, epigenetics, and other disciplines that may result in the emergence of new technologies and methods to better interpret causal relationships between microbiota and obesity.

Obesity (Silver Spring, Md.), 2018

This review summarizes the current understanding of the relationship between gut microbiota and the host as it pertains to the regulation of energy balance and obesity. The paper begins with a brief description of the gut microbiota environment, distribution, and its unique symbiotic relationship with the host. The way that enviromental factors influence microbiota composition and subsequent impact on the host are then described. Next, the mechanisms linking gut dysbiosis with obesity are discussed, and finally current challenges and limitations in understanding the role of gut microbiota in control of obesity are presented. Gut microbiota has been implicated in regulation of fat storage, as well as gut dysbiosis, thus contributing to the development of obesity, insulin resistance, hyperglycemia and hyperlipidemia. However, the underlying mechanisms of these processes are far from being clear and will require complex preclinical and clinical interdisciplinary studies of bacteria and...

Biology, 2020

Emerging new data reported in the international scientific literature show that specific alterations in the human gut microbiota are characteristic in obesity and obesity-related metabolic diseases. Obesity is conditioned by a multitude of factors, and the microbiota is certainly an important player. The analysis of the data obtained from experimental studies allow us to hypothesize that changes in the composition of the microbiota may be the cause, and not simply the consequence, of alterations in human metabolism. Clinical trials on wide samples that investigate the role of diet-induced modulation of the gut microbiota on the host metabolism are needed to understand the interactions at the molecular level for the observed correlations between metabolism and microbiota changes.

Genes & Nutrition

It is widely accepted that metabolic disorders, such as obesity, are closely linked to lifestyle and diet. Recently, the central role played by the intestinal microbiota in human metabolism and in progression of metabolic disorders has become evident. In this context, animal studies and human trials have demonstrated that alterations of the intestinal microbiota towards enhanced energy harvest is a characteristic of the obese phenotype. Many publications, involving both animal studies and clinical trials, have reported on the successful exploitation of probiotics and prebiotics to treat obesity. However, the molecular mechanisms underlying these observed anti-obesity effects of probiotics and prebiotic therapies are still obscure. The aim of this mini-review is to discuss the intricate relationship of various factors, including diet, gut microbiota, and host genetics, that are believed to impact on the development of obesity, and to understand how modulation of the gut microbiota with dietary intervention may alleviate obesity-associated symptoms.

2019

BACKGROUND The prevalence of obesity has increased substantially over recent decades and is associated with considerable health inequalities. Although the causes of obesity are complex, key drivers include over-consumption of highly palatable, energy-dense and nutrient-poor foods, which have a profound impact on the composition and function of the gut microbiome. Alterations to the microbiome may play a critical role in obesity by affecting energy extraction from food and subsequent energy metabolism and fat storage. OBJECTIVE We report the study protocol and recruitment strategy of the PROMISE (PRedictors linking Obesity and the gut MIcrobiomE) study, which characterises the gut microbiome in two populations with markedly different metabolic disease risk (Pacific and European women) and different body fat profiles (normal and obese). It investigates: (1) the role of gut microbiome composition and functionality in obesity and body fat distribution; and (2) the interactions between d...