biostudies-literaturePi YNational Key Basic Research Program of ChinaNational Natural Science Foundation of Chinae00176-20https://www.ebi.ac.uk/biostudies/studies/S-EPMC8534727biostudies-literatureUnknown5(3)Dietary high protein and low carbohydrate levels compromise colonic microbiota and bile acid metabolism, which underlies a detrimental gut environment. However, it remains unclear if the diet-induced changes in colonic health are due to a change in hindgut nutrient availability and what key intermediates link the microbe-epithelium dialogue. To specifically alter the hindgut nutrient substrate availability, here we used a cecally cannulated pig model to infuse corn starch and casein hydrolysate directly into the cecum to generate a stepwise change of carbohydrate/nitrogenous compound (C/N) ratio. Pigs were cecally infused daily with either saline (Control), corn starch (Starch), or casein hydrolysate (Casein) (<i>n</i> = 8 per group), respectively, for 19 days. After infusion, C/N ratios imSystemsIncreasing the Hindgut Carbohydrate/Protein Ratio by Cecal Infusion of Corn Starch or Casein Hydrolysate Drives Gut Microbiota-Related Bile Acid Metabolism To Stimulate Colonic Barrier Function.PMC8534727314300822013CB127300Peng YLiu ZGao KPi YZhu WMu CfalseIncreasing the Hindgut Carbohydrate/Protein Ratio by Cecal Infusion of Corn Starch or Casein Hydrolysate Drives Gut Microbiota-Related Bile Acid Metabolism To Stimulate Colonic Barrier Function.Dietary high protein and low carbohydrate levels compromise colonic microbiota and bile acid metabolism, which underlies a detrimental gut environment. However, it remains unclear if the diet-induced changes in colonic health are due to a change in hindgut nutrient availability and what key intermediates link the microbe-epithelium dialogue. To specifically alter the hindgut nutrient substrate availability, here we used a cecally cannulated pig model to infuse corn starch and casein hydrolysate directly into the cecum to generate a stepwise change of carbohydrate/nitrogenous compound (C/N) ratio. Pigs were cecally infused daily with either saline (Control), corn starch (Starch), or casein hydrolysate (Casein) (<i>n</i> = 8 per group), respectively, for 19 days. After infusion, C/N ratios i2020-01-01T00:00:00Z2020 Jun2026-06-17T06:23:59.345Z2025-02-19T01:26:04.611ZS-EPMC85347273248774110.1128/mSystems.00176-20