Moderate exercise-induced dynamics on key sepsis-associated signaling pathways in the liver

Hari Prasad Osuru; Keita Ikeda; Navya Atluri; Robert H Thiele

doi:10.1186/s13054-023-04551-1

Moderate exercise-induced dynamics on key sepsis-associated signaling pathways in the liver

Crit Care. 2023 Jul 5;27(1):266. doi: 10.1186/s13054-023-04551-1.

Authors

Hari Prasad Osuru¹, Keita Ikeda², Navya Atluri², Robert H Thiele³

Affiliations

¹ Department of Anesthesiology, University of Virginia School of Medicine, P.O. Box 800710-0710, Charlottesville, VA, 22908-0710, USA. ho2b@virginia.edu.
² Department of Anesthesiology, University of Virginia School of Medicine, P.O. Box 800710-0710, Charlottesville, VA, 22908-0710, USA.
³ Department of Anesthesiology, University of Virginia School of Medicine, P.O. Box 800710-0710, Charlottesville, VA, 22908-0710, USA. rht7w@virginia.edu.

Abstract

Background: There is a clear relationship between quantitative measures of fitness (e.g., VO₂ max) and outcomes after surgical procedures. Whether or not fitness is a modifiable risk factor and what underlying biological processes drive these changes are not known. The purpose of this study was to evaluate the moderate exercise training effect on sepsis outcomes (survival) as well as the hepatic biological response. We chose to study the liver because it plays a central role in the regulation of immune defense during systemic infection and receives blood flow directly from the origin of infection (gut) in the cecal ligation and puncture (CLP) model.

Methods: We randomized 50 male (♂) and female (♀) Sprague-Dawley rats (10 weeks, 340 g) to 3 weeks of treadmill exercise training, performed CLP to induce polymicrobial "sepsis," and monitored survival for five days (Part I). In parallel (Part II), we randomized 60 rats to control/sedentary (G1), exercise (G2), exercise + sham surgery (G3), CLP/sepsis (G4), exercise + CLP [12 h (G5) and 24 h (G6)], euthanized at 12 or 24 h, and explored molecular pathways related to exercise and sepsis survival in hepatic tissue and serum.

Results: Three weeks of exercise training significantly increased rat survival following CLP (polymicrobial sepsis). CLP increased inflammatory markers (e.g., TNF-a, IL-6), which were attenuated by exercise. Sepsis suppressed the SOD and Nrf2 expression, and exercise before sepsis restored SOD and Nrf2 levels near the baseline. CLP led to increased HIF1a expression and oxidative and nitrosative stress, the latter of which were attenuated by exercise. Haptoglobin expression levels were increased in CLP animals, which was significantly amplified in exercise + CLP (24 h) rats.

Conclusions: Moderate exercise training (3 weeks) increased the survival in rats exposed to CLP, which was associated with less inflammation, less oxidative and nitrosative stress, and activation of antioxidant defense pathways.

Keywords: CLP; Exercise training; Liver injury; Sepsis-hub genes; Sepsis-survival.

MeSH terms

Animals
Disease Models, Animal
Female
Liver
Male
NF-E2-Related Factor 2*
Rats
Rats, Sprague-Dawley
Sepsis*
Signal Transduction
Superoxide Dismutase

Substances

NF-E2-Related Factor 2
Superoxide Dismutase