Involvement of the gut microbiota in the development of low grade inflammation associated with obesity: Focus on this neglected partner
Université catholique de Louvain, Louvain Drug Research Institute, Metabolism and Nutrition Research Group, Brussels, Belgium.Acta gastro-enterologica Belgica (Impact Factor: 0.91). 04/2010; 73(2):267-9.
Nowadays, the literature provides evidence that obesity, type 2 diabetes and insulin resistance are characterized by a low grade inflammation. Among the environmental factors involved in such diseases, the gut microbiota has been proposed as a key player. This neglected "organ" has been found to be different between healthy and or obese and type 2 diabetic patients. For example, recent data have proposed that dysbiosis of gut microbiota (at phyla, genus, or species level) affects host metabolism and energy storage. Among the mechanisms, metabolic endotoxemia (higher plasma LPS levels), gut permeability and the modulation of gut peptides (GLP-1 and GLP-2) have been proposed as putative targets. Here we discuss 1 degrees the specific modulation of the gut microbiota composition by using prebiotics and 2 degrees the novel findings that may explain how gut microbiota can be involved in the development or in the control of obesity and associated low-grade inflammation.
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- "Even the lung tumors of smokers has considerable association with microbes as well (Cummins and Tangney, 2013). The microbiome has also been shown to secrete metabolites that promote liver cancer through the senescence secretome (Cani and Delzenne, 2010; DiBaise et al., 2008; Kadooka et al., 2010; Pischon et al., 2008; Wang et al., 2014; Yoshimoto et al., 2013). Turnbaugh performed an interesting study where he was able to demonstrate significant effects of diet on the microbiome by transplanting fresh or frozen adult fecal microbial communities into germ-free c57BL/6 J mice (Turnbaugh et al., 2009b). "
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- "The consumption of prebiotics able to favor the proliferation of a given microbiota has also been suggested as a potential strategy to improve obesity. In fact, Cani et al. (2012) demonstrated that prebiotic treatment decreases gut permeability and metabolic endotoxemia and improves insulin sensitivity, steatosis, and lowgrade inflammation via several mechanisms including the following: (i) an increased L cell number and endogenous GLP-1 and GLP-2 production and (ii) an increased leptin sensitivity, which controls energy homeostasis and GLP-1 production . "
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- "However, in the presence of high fat (HF) diet-induced obesity there is a substantial increase in gut pathogenic microbiome and metabolic endotoxemia i.e. when LPS concentration is much higher in the blood in both animals and humans[76,77]. Bacteria and HF diet interact to promote pro-inflammatory changes in the gut which has a strong and significant association with progression of obesity787980. Rodent and human studies demonstrate that chronic inflammation is characterized by macrophage infiltration in adipose tissue during obesity[81,82]. "
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