Article

Gut microbiota modulation with norfloxacin and ampicillin enhances glucose tolerance in mice

Nestlé Research Center, P.O. Box 44, CH 1000 Lausanne, Switzerland.
The FASEB Journal (Impact Factor: 5.04). 08/2008; 22(7):2416-26. DOI: 10.1096/fj.07-102723
Source: PubMed

ABSTRACT

Recent data suggest that the gut microbiota plays a significant role in fat accumulation. However, it is not clear whether gut microbiota is involved in the pathophysiology of type 2 diabetes. To assess this issue, we modulated gut microbiota via antibiotics administration in two different mouse models with insulin resistance. Results from dose-determination studies showed that a combination of norfloxacin and ampicillin, at a dose of 1 g/L, maximally suppressed the numbers of cecal aerobic and anaerobic bacteria in ob/ob mice. After a 2-wk intervention with the antibiotic combination, both ob/ob and diet-induced obese and insulin-resistant mice showed a significant improvement in fasting glycemia and oral glucose tolerance. The improved glycemic control was independent of food intake or adiposity because pair-fed ob/ob mice were as glucose intolerant as the control ob/ob mice. Reduced liver triglycerides and increased liver glycogen correlated with improved glucose tolerance in the treated mice. Concomitant reduction of plasma lipopolysaccharides and increase of adiponectin further supported the antidiabetic effects of the antibiotic treatment in ob/ob mice. In summary, modulation of gut microbiota ameliorated glucose tolerance of mice by altering the expression of hepatic and intestinal genes involved in inflammation and metabolism, and by changing the hormonal, inflammatory, and metabolic status of the host.

Download full-text

Full-text

Available from: Rodrigo Bibiloni
  • Source
    • "Therefore, the effect observed later in life in studies with longer duration of treatment regimens[39,41]probably was due to the treatment being initiated in early life. Depletion of the Gram negative component of the GM has been shown to result in improved glucose tolerance in mice[39,41], and as proposed in a previous study[32], this improvement may simply be due to a decreased number of Gram-negative bacteria leading to reduced transfer of LPS to the systemic circulation, although we were not able to demonstrate differences in LPS levels in plasma. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The importance of the gut microbiota (GM) in disease development has recently received increased attention, and numerous approaches have been made to better understand this important interplay. For example, metabolites derived from the GM have been shown to promote atherosclerosis, the underlying cause of cardiovascular disease (CVD), and to increase CVD risk factors. Popular interest in the role of the intestine in a variety of disease states has now resulted in a significant proportion of individuals without coeliac disease switching to gluten-free diets. The effect of gluten-free diets on atherosclerosis and cardiovascular risk factors is largely unknown. We therefore investigated the effect of a gluten-free high-fat cholesterol-rich diet, as compared to the same diet in which the gluten peptide gliadin had been added back, on atherosclerosis and several cardiovascular risk factors in apolipoprotein E-deficient (Apoe-/-) mice. The gluten-free diet transiently altered GM composition in these mice, as compared to the gliadin-supplemented diet, but did not alter body weights, glucose tolerance, insulin levels, plasma lipids, or atherosclerosis. In parallel, other Apoe-/- mice fed the same diets were treated with ampicillin, a broad-spectrum antibiotic known to affect GM composition. Ampicillin-treatment had a marked and sustained effect on GM composition, as expected. Furthermore, although ampicillin-treated mice were slightly heavier than controls, ampicillin-treatment transiently improved glucose tolerance both in the absence or presence of gliadin, reduced plasma LDL and VLDL cholesterol levels, and reduced aortic atherosclerotic lesion area. These results demonstrate that a gluten-free diet does not seem to have beneficial effects on atherosclerosis or several CVD risk factors in this mouse model, but that sustained alteration of GM composition with a broad-spectrum antibiotic has beneficial effects on CVD risk factors and atherosclerosis. These findings support the concept that altering the microbiota might provide novel treatment strategies for CVD.
    Preview · Article · Jan 2016 · PLoS ONE
    • "A major effect was observed in male patients who did not have cardiac surgery and were older than 65 since they, indeed, developed obesity. Antibiotic treatment has also been indicated to prevent obesity, by improving glucose tolerance and improving endotoxemia (Cani et al. 2008; Membrez et al. 2008). Evidence in mice suggests that antibiotic therapy has a considerable impact on adiposity and plasma LPS levels, oxidative stress, macrophage infiltration in adipose tissue, inflammation and metabolic disorders (Cani et al. 2008; Bech-Nielsen et al. 2012). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Recently, a great deal of interest has been expressed regarding strategies to tackle worldwide obesity because of its accelerated wide spread accompanied with numerous negative effects on health and high costs. Obesity has been traditionally associated with an imbalance in energy consumed when compared to energy expenditure. However, growing evidence suggests a less simplistic event in which gut microbiota plays a key role. Obesity, in terms of microbiota, is a complicated disequilibrium that presents many unclear complications. Despite this, there is special interest in characterizing compositionally and functionally the obese gut microbiota with the help of in vitro, animal and human studies. Considering the gut microbiota as a factor contributing to human obesity represents a tool of great therapeutic potential. This paper reviews the use of antimicrobials, probiotics, fecal microbial therapy, prebiotics and diet to manipulate obesity through the human gut microbiota and reveals inconsistencies and implications for future study.
    No preview · Article · Jul 2015 · Genes & Nutrition
  • Source
    • "This process is dose-dependent and does not achieve saturation at up to 920 mg/dL of ethanol [11]. This is in line with the observations that (i) SIBO and gut hyperpermeability are closely associated with the progression from simple steatosis to NASH [6,38–42], (ii) SIBO eradication with oral antibiotics prevents the development of both NAFLD and AFLD [43] [44] [45] [46] [47], (iii) germ-free mice are resistant to both diet-induced obesity and NAFLD [48] [49], (iv) rats with experimentally-induced SIBO produce significantly more EE than controls, and (v) intragastric administration of sucrose in these animals elicits a 3- fold increase in portal concentrations of ACD with only modest elevation of systemic BAC [11]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Nonalcoholic fatty liver disease (NAFLD) and alcoholic fatty liver disease (AFLD) are so similar that only a detailed history of alcohol intake can distinguish one from the other. Because subjects with NAFLD produce significantly more endogenous ethanol (EE) than controls, some researchers suspected that these similarities are not merely coincidental. For this reason, it was attempted to show that NAFLD is actually an endogenous alcoholic fatty liver disease (EAFLD). However, negligible blood-alcohol concentration (BAC) and the inability of gut microbiota to produce hepatotoxic concentrations of EE rejected this hypothesis. To clarify these conflicting results, we provide a mechanistic framework explaining how NAFLD may be an EAFLD. First of all, the key finding is that ethanol is a prodrug, enabling the idea that AFLD may develop with negligible/absent BAC. Second, extrahepatic acetaldehyde (ACD) alone recapitulates AFLD and is about 330-fold more hepatotoxic than that generated inside the liver. Third, gut microbiota can even produce much larger amounts of EE than those currently considered cirrhotogenic for man. Fourth, an extensive gut-liver axis first-pass metabolism of ethanol prevents the development of significant BAC in NAFLD. Fifth, all genes involved in EE metabolism are upregulated in the livers of patients with nonalcoholic steatohepatitis (NASH). Last, overexpression of the gene encoding alcohol dehydrogenase (ADH) 4 implicates liver exposure to high concentrations of EE. In conclusion, this work provides mechanistic explanation supporting the assumption that NAFLD may indeed be an EAFLD. If validated by further testing, the hypothesis may help develop novel therapeutic and preventive strategies against this ubiquitous condition. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Full-text · Article · Apr 2015 · Medical Hypotheses
Show more