Parenteral succinate reduces levels of reactive oxygen species without changing serum caspase-3 levels in septic rats.

INTRODUCTION: Sepsis is a syndrome of physiological, pathological, and biochemical disorders with several processes co-occurring; reactive oxygen species (ROS) production and apoptosis are 2 of them. Succinate is a Krebs cycle intermediate that is oxydized in complex II of the mitochondria. This study aims to investigate the influence of succinate infusion on these processes. MATERIAL AND METHODS: Sepsis was induced with caecal ligation and puncture in 200 gr Sprague Dawley rats. Four groups were formed with 10 animals (1 - control, 2 - succinate, 3 - sepsis, and 4 - sepsis + succinate). 5 mmol kg-1 of intraperitoneal succinate were administered twice in groups 2 and 4. ROS and caspase-3 levels were measured. RESULTS: Overall, ROS levels (P = 0.017), but not caspase-3 levels (P = 0.89) differed significantly between the groups. The succinate administration reduced serum ROS levels (group 4 vs. 3) in a statistically significant way [0.0623 units (95% CI: 0.0547-0.0699) vs. 0.0835 (0.06-0.106), P = 0.017)], but it did not reduce serum caspase-3 levels (P = 0.39). There was no correlation between serum ROS levels and serum caspase-3 levels. CONCLUSIONS: In this model, ROS levels were reduced with succinate infusion, but caspase-3 levels were not. In addition, ROS levels and apoptosis levels are not correlated, which suggests that those processes occur at different times.

Serum reactive oxygen species and apoptosis markers in septic patients.

INTRODUCTION: Oxidative stress is one of the pathophysiological processes that occur during sepsis. Reactive oxygen species (ROS) production causes lipid peroxidation and protein and DNA damage. ROS and DNA damage triggers apoptosis. Several studies have shown that organ failure in sepsis is mediated by apoptosis. The aim of this study is to investigate the levels of serum ROS and serum caspase-3 in septic patients and healthy volunteers, and their correlation. MATERIAL AND METHODS: Serum samples were taken within the first 12 hours of ICU stay. The dichlorofluorescein technique was used to determine serum ROS levels, and the ELISA technique was used to quantify serum caspase-3 in septic patients and healthy volunteers. RESULTS: There was no difference in serum ROS levels between healthy volunteers and septic patients (P = 0.26), and there was a significant difference in serum caspase-3 levels between healthy volunteers and septic patients (P < 0.001). There was no difference between patients who lived and died in the intensive care unit (ICU) in serum ROS (P = 0.089) and serum caspase-3 (P = 0.18). There was no correlation between both markers (R = -0.0013, P = 0.98). CONCLUSIONS: We conclude that there is no correlation between serum ROS and caspase-3; therefore, both processes might not be associated during the first hours of ICU stay.