Microbiota of the Gut: Antibiotic-Induced Dysbiosis and the Adverse Effects on Human Health (original) (raw)
Related papers
2013
The excessively widespread use of antibiotics has created many threats. A well-known problem is the increasing bacterial resistance to antibiotics, which has clearly become a worldwide challenge to the effective control of infections by many pathogens. But, beyond affecting the pathogenic agents for which it is intended, antibiotic treatment also affects the mutualistic communities of microbes that inhabit the human body. As they inhibit susceptible organisms and select for resistant ones, antibiotics can have strong immediate effects on the composition of these communities, such as the proliferation of resistant opportunists that can cause accute disease. Furthermore, antibiotic-induced microbiota alterations are also likely to have more insidious effects on long-term health. In the case of the gut microbiota, this community interacts with many crucial aspects of human biology, including the regulation of immune and metabolic homeostasis, in the gut and beyond. It follows that anti...
Fire in the Forest: Adverse Effects of Antibiotics on the Healthy Human Gut Microbiome
International Journal of Medical Reviews
Antimicrobial resistance, especially the emergence of multidrug-resistant human pathogens, remains a serious public health crisis across the globe. The human gut microbiome regulates essential human functions including digestion, energy metabolism, brain function, and immunity by modulating multiple endocrine, neural, and immune pathways of the host. Increasing evidence shows adverse effects of antibiotics on the community structure and functions of healthy gut microbiomes. Short-term antibiotic treatment is able to change the richness and diversity of species into a long-term dysbiotic state. The colonization of invading pathogens is encouraged because of decreased competitive exclusion. Furthermore, the accumulation of antimicrobial resistant genes in the gut microbiome (gut resistome) facilitates the emergence of multidrug-resistant nosocomial pathogens. In this study, the adverse effects of antibiotics on the gut microbiome are highlighted in terms of dysbiosis and the accumulation of resistance genes. In light of evidence of such adverse impacts, several epidemiological studies have been conducted on traditional culture techniques and 16S rRNA metagenomics to assess the compositional and functional changes occurring in the gut microbiome after exposure to antibiotics. They have failed to agree on specific antibioticassociated microbiome and its functional redundancy subsequent to exposure to antibiotics. This mini-review describes the composition and role of a healthy microbiome to understand and appraise the value of gut microbiome and summarizes the current understanding of adverse effects of antibiotics on it.
Antibiotics and the Human Gut Microbiome: Dysbioses and Accumulation of Resistances
Frontiers in Microbiology, 2016
The human microbiome is overly exposed to antibiotics, due, not only to their medical use, but also to their utilization in farm animals and crops. Microbiome composition can be rapidly altered by exposure to antibiotics, with potential immediate effects on health, for instance through the selection of resistant opportunistic pathogens that can cause acute disease. Microbiome alterations induced by antibiotics can also indirectly affect health in the long-term. The mutualistic microbes in the human body interact with many physiological processes, and participate in the regulation of immune and metabolic homeostasis. Therefore, antibiotic exposure can alter many basic physiological equilibria, promoting long-term disease. In addition, excessive antibiotic use fosters bacterial resistance, and the overly exposed human microbiome has become a significant reservoir of resistance genes, contributing to the increasing difficulty in controlling bacterial infections. Here, the complex relationships between antibiotics and the human microbiome are reviewed, with focus on the intestinal microbiota, addressing (1) the effects of antibiotic use on the composition and function of the gut microbiota, (2) the impact of antibiotic-induced microbiota alterations on immunity, metabolism, and health, and (3) the role of the gut microbiota as a reservoir of antibiotic resistances.
Current Obesity Reports
Purpose of Review In this review, we summarize current evidence on the association between antibiotics and the subsequent development of obesity through modulation of the gut microbiome. Particular emphasis is given on (i) animal and human studies and their limitations; (ii) the reservoir of antibiotics in animal feed, emerging antibiotic resistance, gut dysbiosis, and obesity; (iii) the role of infections, specifically viral infections, as a cause of obesity; and (iv) the potential therapeutic approaches other than antibiotics to modulate gut microbiome. Recent Findings Overall, the majority of animal studies and meta-analyses of human studies on the association between antibiotics and subsequent development of obesity are suggestive of a link between exposure to antibiotics, particularly early exposure in life, and the development of subsequent obesity as a result of alterations in the diversity of gut microbiota. The evidence is strong in animal models whereas evidence in humans is inconclusive requiring well-designed, long-term longitudinal studies to examine this association. Based on recent meta-analyses and epidemiologic studies in healthy children, factors, such as the administration of antibiotics during the first 6 months of life, repeated exposure to antibiotics for ≥ 3 courses, treatment with broad-spectrum antibiotics, and male gender have been associated with increased odds of overweight/obesity. Early antibiotic exposure in animal models has shown that reductions in the population size of specific microbiota, such as Lactobacillus, Allobaculum, Rikenellaceae, and Candidatus Arthromitus, are related to subsequent adiposity. These data suggest that the loss of diversity of the gut microbiome, especially early in life, may have potential long-term detrimental effects on the adult host gut microbiome and metabolic health. Genetic, environmental, and age-related factors influence the gut microbiome throughout the lifetime. More large-scale, longer-term, longitudinal studies are needed to determine whether changes that occur in the microbiome after exposure to antibiotics, particularly early exposure, are causal of subsequent weight gain or consequent of weight gain in humans. Summary Further well-designed, large-scale RCTs in humans are required to evaluate the effects of administration of antibiotics, particularly early administration, and the subsequent development of overweight/obesity. Therapeutic interventions, such as
Low-dosage antibiotic intake can disturb gut microbiota in mice
CyTA - Journal of Food, 2018
The proportion of different microbial populations in gut microbiota (GM) is an important factor that in recent years has been linked to obesity and numerous metabolic diseases. Antibiotics are one of the factors that can dramatically alter GM at therapeutic dosages, but their effects at subtherapeutic doses have been less investigated. Here, a mouse model using a total of 60 C57BL/6J mice was used to compare the evolution of total microbiota, four phyla and two genera considered as probiotics in control mice, and mice exposed to 50 µg/kg of ampicillin, 100 µg/kg of tetracycline or 100 µg/kg of sulphadiazine. The results obtained found that the presence of antibiotics in foods, even at trace concentrations, can disturb mouse GM, causing in all antibiotics significant increases of Proteobacteria (about 2 log CFU/g) or decreases of Bifidobacterium and Lactobacillus (about 1 log CFU/g) for the cases of ampicillin and sulphadiazine. La ingesta de bajas dosis de antibióticos es capaz de alterar la microbiota intestinal en ratones RESUMEN La composición de las diferentes poblaciones microbianas presentes en la microbiota intestinal humana es un aspecto importante que en los últimos años ha sido relacionada tanto con la obesidad con como muchas patologías metabólicas. Los antibióticos son uno de los agentes que pueden alterar de manera radical la composición de la microbiota intestinal cuando se utilizan a dosis terapéuticas, pero sus efectos a dosis sub-terapéuticas han sido menos investigados. Para este fin, se ha realizado un ensayo empleando 60 ratones C57BL/6J para comparar la evolución de la microbiota total, así como 4 filos y 2 géneros bacterianos beneficiosos en ratones control, ratones expuestos a 50 µg/kg de ampicilina, ratones expuestos a 100 µg/kg de tetraciclina y ratones expuestos a 100 µg/kg de sulfadiacina. Los resultados obtenidos mostraron que la presencia de antibióticos en los alimentos, incluso a concentraciones traza, pueden alterar la microbiota intestinal de los ratones, causando todos los antibióticos un incremento significativo de Proteobacteria (aproximadamente 2 log ufc/g), o descensos en los géneros Bifidobacterium y Lactobacillus (aproximadamente 1 log ufc/g) en los casos de la ampicilina y la sulfadiacina.
Antibiotics, gut microbiome and obesity
Clinical endocrinology, 2018
Antibiotics have been hailed by many as "miracle drugs" that have been effectively treating infectious diseases for over a century, leading to a marked reduction in morbidity and mortality. However, with the increasing use of antibiotics, we are now faced not only with the increasing threat of antibiotic resistance, but also with a rising concern about potential long-term effects of antibiotics on human health, including the development of obesity. The obesity pandemic continues to increase, a problem that affects both adults and children alike. Disruptions to the gut microbiome have been linked to a multitude of adverse conditions, including obesity, type 2 diabetes, inflammatory bowel diseases, anxiety, autism, allergies, and autoimmune diseases. This review focuses on the association between antibiotics and obesity, and the role of the gut microbiome. There is strong evidence supporting the role of antibiotics in the development of obesity in well-controlled animal mode...
The impact of diet and antibiotics on the gut microbiome
CourseSource, 2019
The goal of this article is to describe an active learning exercise that can be used in a variety of advanced microbiology courses, including bacterial physiology, ecology, or systems biology. The gut microbiome is a multi-species bacterial community that is impacted by outside factors, such as the food we consume or treatments with antibiotics, and impacts our health. In this active learning experience; students start with a simple 'pasta' simulation of a gut microbiome, adapted from a previously published lesson, where different types of pasta in a plastic bag simulate different bacteria in the gut and the composition of the pasta types is representative of diet related differences in the microbiome. Students will then mimic an antibiotic treatment by removing certain pasta/bacteria and replacing them with beans/different bacteria. Next, students will analyze the gut microbiome at the level of phylum, genus, or species. With the help of assigned scientific literature, students will learn how the composition of the gut microbiome responds to diet, a process that is accompanied by the synthesis of bacterial fermentation and other bacterial metabolic products that elicit a molecular response in the host intestinal cells. Students will gain an initial understanding of how these changes impact human health. Through this experience, students will increase their knowledge of bacterial metabolic pathways and products, improve their understanding of the complex community that constitutes the microbiome, analyze the microbiome at multiple systematic levels, and apply their knowledge in a context that is relevant to human health.
Cell metabolism, 2016
The gut microbiota has been implicated in obesity and cardiometabolic diseases, although evidence in humans is scarce. We investigated how gut microbiota manipulation by antibiotics (7-day administration of amoxicillin, vancomycin, or placebo) affects host metabolism in 57 obese, prediabetic men. Vancomycin, but not amoxicillin, decreased bacterial diversity and reduced Firmicutes involved in short-chain fatty acid and bile acid metabolism, concomitant with altered plasma and/or fecal metabolite concentrations. Adipose tissue gene expression of oxidative pathways was upregulated by antibiotics, whereas immune-related pathways were downregulated by vancomycin. Antibiotics did not affect tissue-specific insulin sensitivity, energy/substrate metabolism, postprandial hormones and metabolites, systemic inflammation, gut permeability, and adipocyte size. Importantly, energy harvest, adipocyte size, and whole-body insulin sensitivity were not altered at 8-week follow-up, despite a still co...
Antibiotic is a type of antimicrobial drug used for treating and preventing any infection caused by pathogenic bacteria. The widely accepted use of antibiotics has saved millions of human lives all over the world; however, they highly influenced the human microbiome. Human microbiome performs an array of important functions that help us to survive and keep away dangerous disease. Mounting evidence shows that antibiotics alter the constituent of this microbiome and influence the function of the immune system, our ability to resist infection, and our capacity for processing food. Therefore, it is now more important than ever to revisit how we use antibiotics. This review focused on some collateral effects and problems associated with antibiotic use on human gut microbiome. Evidence of histological alternation of intestinal epithelia was considered.