Darlington Daniel N, Berger Reese B, Keesee Jeffrey D, Nicholson Susannah E, Wu Xiaowu
Blood and Shock Resuscitation, United States Army Institute of Surgical Research, Fort Sam Houston, TX 78234, and.
The Department of Surgery, Trauma and Emergency Surgery, University of Texas Health, San Antonio, TX 78229.
Shock. 2025 Jun 26. doi: 10.1097/SHK.0000000000002645.
Severe trauma and hemorrhage in rats lead to changes in the beta diversity of the commensal bacteria found in the gut. Because Short-Chain Fatty Acids (SCFA) are produced by these bacteria, SCFA concentration may also change following trauma and hemorrhage and reflect these alterations in the microbiome.
To determine whether changes in SCFA occur after trauma and hemorrhage in the feces and plasma of rodents.
Polytrauma was induced in isoflurane-anesthetized Sprague-Dawley rats by damage to the small intestine, liver, right leg skeletal muscle, and femur, followed by 20% hemorrhage. Whole blood resuscitation was performed at 1 hour (20%). Rats were euthanized at 2 hours and feces and plasma were analyzed for short-chain fatty acids (SCFA) by liquid chromatography tandem mass spectroscopy.
Of twenty-one SCFA analyzed in the feces and plasma, 11 were measurable. In feces, five demonstrated a significant elevation after 2 hours of severe trauma and hemorrhage (n-8) including propionic (37775 ± 8919 vs. 146591 ± 46734 nM/mg protein: mean ± SEM), pentanoic (10975 ± 2981 vs. 41828 ± 10645), 2-methyl propionic (2621 ± 523 vs. 13798 vs. 2083), 4-methyl pentanoic (1134 ± 302 vs. 4320 ± 1029) and 3-phenyl propionic acid (42194 ± 4863 vs. 153024 ± 38473). The addition of whole blood resuscitation did not change these responses, but led to an additional significant elevation in butyric (68551 ± 10786 vs. 369951 ± 79515) and hexanoic acid (24548 ± 6791 vs. 102002 ± 32069). There was no change in SCFA after trauma, hemorrhage or resuscitation in the plasma (n = 6).
Two hours of severe trauma and hemorrhage lead an elevation in many SCFAs in rat feces. No change in SCFA was found in plasma. Because SCFA are primarily derived from commensal bacteria in the gut, these data suggest that the measurement of SCFA could be used as an index of changes in the gut microbiome in pathological condition including trauma and hemorrhage.
