n-6 High Fat Diet Induces Gut Microbiome Dysbiosis and Colonic Inflammation

• Published in: International journal of molecular sciences Vol. 22; no. 13; p. 6919
• Main Authors: Selmin, Ornella I., Papoutsis, Andreas J., Hazan, Sabine, Smith, Christopher, Greenfield, Nick, Donovan, Micah G., Wren, Spencer N., Doetschman, Thomas C., Snider, Justin M., Snider, Ashley J., Chow, Sherry H.-H., Romagnolo, Donato F.
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.07.2021; MDPI
• Subjects: Age; Animals; Body weight; Carbohydrates; Colon; Cyclooxygenase-2; Diet; Digestive system; Digestive tract; Dysbacteriosis; dysbiosis; Fatty acids; gut; High fat diet; Histopathology; Inflammation; Intestinal microflora; Microbiomes; Microbiota; Oils & fats; omega-6; Palm oil; Plasma; Plasma levels; Soybean oil; Soybeans; Vegetable oils; Weaning; Young adults; United States > US
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms22136919

Background: Concerns are emerging that a high-fat diet rich in n-6 PUFA (n-6HFD) may alter gut microbiome and increase the risk of intestinal disorders. Research is needed to model the relationships between consumption of an n-6HFD starting at weaning and development of gut dysbiosis and colonic inflammation in adulthood. We used a C57BL/6J mouse model to compare the effects of exposure to a typical American Western diet (WD) providing 58.4%, 27.8%, and 13.7% energy (%E) from carbohydrates, fat, and protein, respectively, with those of an isocaloric and isoproteic soybean oil-rich n-6HFD providing 50%E and 35.9%E from total fat and carbohydrates, respectively on gut inflammation and microbiome profile. Methods: At weaning, male offspring were assigned to either the WD or n-6HFD through 10–16 weeks of age. The WD included fat exclusively from palm oil whereas the n-6HFD contained fat exclusively from soybean oil. We recorded changes in body weight, cyclooxygenase-2 (COX-2) expression, colon histopathology, and gut microbiome profile. Results: Compared to the WD, the n-6HFD increased plasma levels of n-6 fatty acids; colonic expression of COX-2; and the number of colonic inflammatory and hyperplastic lesions. At 16 weeks of age, the n-6HFD caused a marked reduction in the gut presence of Firmicutes, Clostridia, and Lachnospiraceae, and induced growth of Bacteroidetes and Deferribacteraceae. At the species level, the n-6HFD sustains the gut growth of proinflammatory Mucispirillum schaedleri and Lactobacillus murinus. Conclusions: An n-6HFD consumed from weaning to adulthood induces a shift in gut bacterial profile associated with colonic inflammation.