Regular and moderate exercise before experimental sepsis reduces the risk of lung and distal organ injury

Abstract

<jats:p>Physical activity modulates inflammation and immune response in both normal and pathologic conditions. We investigated whether regular and moderate exercise before the induction of experimental sepsis reduces the risk of lung and distal organ injury and survival. One hundred twenty-four BALB/c mice were randomly assigned to two groups: sedentary (S) and trained (T). Animals in T group ran on a motorized treadmill, at moderate intensity, 5% grade, 30 min/day, 3 times a week for 8 wk. Cardiac adaptation to exercise was evaluated using echocardiography. Systolic volume and left ventricular mass were increased in T compared with S group. Both T and S groups were further randomized either to sepsis induced by cecal ligation and puncture surgery (CLP) or sham operation (control). After 24 h, lung mechanics and histology, the degree of cell apoptosis in lung, heart, kidney, liver, and small intestine villi, and interleukin (IL)-6, KC (IL-8 murine functional homolog), IL-1β, IL-10, and number of cells in bronchoalveolar lavage (BALF) and peritoneal lavage (PLF) fluids as well as plasma were measured. In CLP, T compared with S groups showed: 1) improvement in survival; 2) reduced lung static elastance, alveolar collapse, collagen and elastic fiber content, number of neutrophils in BALF, PLF, and plasma, as well as lung and distal organ cell apoptosis; and 3) increased IL-10 in BALF and plasma, with reduced IL-6, KC, and IL-1β in PLF. In conclusion, regular and moderate exercise before the induction of sepsis reduced the risk of lung and distal organ damage, thus increasing survival.</jats:p>

Regular Exercise Enhances the Immune Response Against Microbial Antigens Through Up-Regulation of Toll-like Receptor Signaling Pathways

“…Recently, a series of studies have demonstrated that regular moderate exercise can decrease the rate of upper respiratory tract infections [6] and that regular exercise can induce slight changes in the immune system [14,29]; thus, indicating an immunomodulatory role for exercise [15,30]. However, the immune changes induced by regular exercise remain to be clarified.…”

Detailed Characterization of a Long-Term Rodent Model of Critical Illness and Recovery

“…Treadmill exercise capacity has been assessed in animal models of heart failure (48, 49), diabetes (50), aging (51,52) and skeletal muscle pathophysiology (53)(54)(55)(56). Motorised rodent treadmills have been used in sepsis models though as a means of determining the impact of endurance training on outcomes (57)(58)(59)(60). The early and persisting fall in treadmill exercise capacity reflected the decrease in grip strength and the myography fatigue index shown with repetitive twitch.…”

Dissociation of Inflammatory Mediators and Function

“…Understanding the mechanism raises the possibility of blocking the process and lessening the ultimate level of lung injury, for example, inhibition of phosphodiesterase-2A or immune modulation by hypertonic saline (26). It is possible that with more severe sepsis or longer exposure following CLP (27,28), the injury may have been more marked.…”