Depletion of the gut microbiota using antibiotic cocktail reduces aortic aneurysms and dissections in mice

To induce a sporadic aortic aneurysm and dissection (AAD) mouse model, Male mice were fed a high-fat diet for 8 weeks. During the last 4 weeks, osmotic mini-pumps were implanted subcutaneously on the dorsal side to deliver angiotensin II continuously. Mice fed standard chow and implanted with pumps containing saline were used as controls. AAD_Abx group received an antibiotic cocktail (Abx, 1 g/L ampicillin, 1 g/L metronidazole, 1 g/L neomycin, and 0.5 g/L vancomycin, MCE) dissolved in autoclaved water, supplemented with 0.5% w/v sucralose for palatability, for 8 weeks. Drinking water was replaced every four days. Mice in the AAD group received drinking water containing the same proportion of sweetener for 8 weeks. Average daily water consumption was similar across all groups. Two days before the end of the animal experiment, fecal samples were collected from two groups of mice.