Associations between the gut microbiota and host responses to high altitude
Abstract
Hypobaric hypoxia and dietary protein and fat intakes have been independently associated with an altered gastrointestinal (GI) environment and gut microbiota, but little is known regarding host-gut microbiota interactions at high altitude (HA) and the impact of diet macronutrient composition. This study aimed to determine the effect of dietary protein:fat ratio manipulation on the gut microbiota and GI barrier function during weight loss at high altitude (HA) and to identify associations between the gut microbiota and host responses to HA. Following sea-level (SL) testing, 17 healthy males were transported to HA (4,300 m) and randomly assigned to consume provided standard protein (SP; 1.1 g·kg−1·day−1, 39% fat) or higher protein (HP; 2.1 g·kg−1·day−1, 23% fat) carbohydrate-matched hypocaloric diets for 22 days. Fecal microbiota composition and metabolites, GI barrier function, GI symptoms, and acute mountain sickness (AMS) severity were measured. Macronutrient intake did not impact fecal microbiota composition, had only transient effects on microbiota metabolites, and had no effect on increases in small intestinal permeability, GI symptoms, and inflammation observed at HA. AMS severity was also unaffected by diet but in exploratory analyses was associated with higher SL-relative abundance of Prevotella, a known driver of interindividual variability in human gut microbiota composition, and greater microbiota diversity after AMS onset. Findings suggest that the gut microbiota may contribute to variability in host responses to HA independent of the dietary protein:fat ratio but should be considered preliminary and hypothesis generating due to the small sample size and exploratory nature of analyses associating the fecal microbiota and host responses to HA.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 01, 2018
- Source ID
- 10.1152/ajpgi.00253.2018
Entities
People
- Andrew J Young
- Claire E Berryman
- Ida G. Pantoja-feliciano
- J Philip Karl
- Jennifer C Rood
- Patrick N. Radcliffe
- Stefan M. Pasiakos
- Tobyn A. Branck
Organizations
- Oak Ridge Institute for Science and Education
- Pennington Biomedical Research Center
- United States Army Medical Research and Development Command
- United States Army Soldier Systems Center
- United States Department of Defense