Obesity associated gut microbiota

Obesity-Associated Gut Microbiota Characterization and Dietary Modulation... 

OBESITY-ASSOCIATED GUT MICROBIOTA CHARACTERIZATION AND DIETARY MODULATION... 

In summary, the variability reported in the obesity-associated gut microbiota in the representative studies listed above suggests a need for detailed characterization at a lower and "functional" taxonomic level rather than at the level of the phylum as in earlier studies, to potentially serve as a better target for modulation. 

Million M, Maraninchi M, Henry M, et al. Obesity-associated gut microbiota is enriched in Lactobacillus reuteri and depleted in Bifidobacterium animalis and Methanobrevibacter smithii. Int J Obesity. 2012 36(6) 817—825. 

Cani PD, Delzenne NM. Interplay between obesity and associated metabolic disorders new insights into the gut microbiota. Curr Opin... 

Cani PD, Delzenne NM. Involvement of the gut microbiota in the development of low grade inflammation associated with obesity focus on this neglected partner. Acta Gastroenterol Belg. 2010 73 267-269. 

The mechanism of induction of low-grade chronic inflammation that accompanies HF-diet-induced obesity was demonstrated to be dependent on TLR-4. Interestingly, in the absence of TLR-4/CD14 receptor for LPS, no low-grade chronic inflammation and insulin resistance were induced by HF feeding in mice. Recently also TLR-2 and TLR-5 were shown to be involved in the innate immune system activation that is responsible for the inflammation induced after HF diet. These results confirm gut microbiota implication in the onset of metabolic disorders associated with obesity. Moreover, in animal studies at least, this high-fat-induced metabohc endotoxemia and subsequent metabolic disease may be reversed using prebiotic dietary fibers and certain bacterial supplements... 

In short, it is hard to conclude whether the gut microbiota is playing an active causative role in the development of obesity, or whether the obesity-associated profile of microbiota is simply in response to an obese state or the underlying diet. However, considering that the gut microbiota has been implicated in the onset of obesity in several animal studies, is modified by obesity and obesity-inducing diets, and appears to mediate some mechanisms of diet-related obesity and associated conditions, there is reasonable evidence to suggest its importance in metabolic health. The "chicken and egg" question therefore seems inconsequential compared to the significance of elucidating the role of the gut microbiota in host nutritional metabolism. 

Cani PD, Osto M, Geurts L, Everard A. Involvement of gut microbiota in the development of low-grade inflammation and type 2 diabetes associated with obesity. Gut Microbes. 2012 3(4) 279—288. 

Some of the studies mentioned above were found in in vitro models and should be interpreted with caution. As described later, berberine has low bioavailability and shows poor absorption, supporting the hypothesis that berberine may exert its antihyper-glycetnic effect in the intestinal tract before absorptum before reaching other organs like pancreas or liver [2]. Recent evidences suggest that the gut microbiota compositirui is associated with obesity and type 2 diabetes [31], which are closely associated with... 

Schwiertz A, Taras D, Schaefer K, et al. Microbiota and SCFA in lean and overweight healthy subjects. Obesity. 2010 18(1) 190—195. Jumpertz R, Due Son L, Turnbaugh PJ, et al. Energy-balance studies reveal associations between gut microbes, caloric load, and nutrient absorption in humans. Am ] Clin Nutr. 2011 94(1) 58—65. 

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