EPicks: Exercise in hypobaric hypoxia increases markers of intestinal injury and GI distress

In this EPicks video, Dr Zach McKenna talks about his latest research investigating the impact of concurrent hypoxic exposure on exercise-induced intestinal injury and symptoms of GI distress.

Find out more in Experimental Physiology:

Paper Details

April - Volume 107 Issue 4 Pages 326-336

Exercise in hypobaric hypoxia increases markers of intestinal injury and symptoms of gastrointestinal distress

Zachary J. McKenna, Zachary J. Fennel, Quint N. Berkemeier, Roberto C. Nava, Fabiano T. Amorim, Michael R. Deyhle, Christine M. Mermier
107(4), pp 326-336, https://physoc.onlinelibrary.wiley.co...

Transcript:

Hello, my name is Zach McKenna, and I am from the university of New Mexico in the department of health exercise and sports science. I am excited to share our recent work published in experimental physiology titled: exercise in hypobaric hypoxia increases markers of intestinal injury and symptoms of gastrointestinal distress. The overall goal of this study was to better understand the impact of concurrent hypoxic exposure on exercise-induced intestinal injury and symptoms of GI distress.

We had participants cycle for 60-minutes at 65% of their VO2max in two conditions: once in normoxia at a local altitude of about 1600 m and once in hypoxia at an altitude of 4300 m which was simulated using a hypobaric chamber. During the exercise bout we assessed for GI symptoms, and pre and post blood samples were assayed for markers of intestinal barrier injury.

We noted significant increases in intestinal fatty acid binding protein, claudin-3, and LPS binding protein following exercise in hypoxia. Whereas exercise in normoxia did not cause an increase in these markers. In addition, participants reported more frequent and severe GI symptoms during exercise in hypoxia compared to normoxia. We next ran correlations to determine if there was a relationship between our markers of intestinal barrier injury and the GI symptoms which were reported during exercise. We found that the magnitude of change for these biomarkers was significantly correlated with GI symptomology.

Collectively our findings indicate that cycling exercise performed at a simulated altitude of 4300 m increases biomarkers of intestinal barrier injury and symptoms of GI distress. In addition, the significant relationship between these variables is consistent with the theory that loss of intestinal barrier integrity may contribute to the GI symptoms which are reported during exercise in hypoxia. Future studies are needed to determine the mechanisms of GI injury including direct measures of intestinal permeability and the role of contributing factors such as pro-inflammatory cytokines.