Polyphenol extracts interfere with bacterial lipopolysaccharide in vitro and decrease postprandial endotoxemia in human volunteers

• Main Authors: Ximena Wong, Ana María Madrid, Karina Tralma, Romina Castillo, Catalina Carrasco-Pozo, Paola Navarrete, Caroll Beltrán, Edgar Pastene, Martin Gotteland
• Format: Article
• Language: English
• Published: Elsevier 2016-10-01
• Series: Journal of Functional Foods
• Subjects: Proanthocyanidins; Lipase; Lipopolysaccharide; Obesity; Triacylglycerol; Interleukin-6
• Online Access: http://www.sciencedirect.com/science/article/pii/S1756464616302213

The intestinal absorption of bacterial lipopolysaccharide (LPS) and dietary fat has been implicated in the development of metabolic endotoxemia. This study first compared the ability of polyphenol extracts from grape, cranberry, avocado and apple to interfere with pancreatic lipase and LPS in vitro. The grape extract displayed a higher inhibitory activity of lipase (IC50 = 8.6 ± 1.1 mg/ml) and LPS binding (IC50 = 90 ± 1.1 µg/ml). Then, a study was carried out in 12 normal weight and 17 overweight/obese subjects to determine the effect of this extract on the postprandial changes in plasma triacylglycerols, LPS and IL-6. The presence of small intestine bacterial overgrowth (SIBO), in which higher levels of bacteria and eventually LPS are present in the upper intestine, i.e. where dietary fat absorption occurs, was also evaluated. Compared with placebo, the grape extract did not affect postprandial triacylglycerolemia but decreased plasma LPS, without affecting the IL-6-associated inflammatory response. SIBO did not affect these variables.