In Vivo Visualization of Reactive Oxidants and Leukocyte-Endothelial Adherence Following Hemorrhagic Shock

Abstract

The generation of oxygen radicals during leukocyte-endothelial cell interaction is considered to represent one of the fundamental steps of microvascular injury following ischemia and reperfusion. Indirect evidence also suggests that this relationship may be important following hemorrhagic shock. The purpose of this study was to characterize the temporal changes of reactive oxygen species (ROS) in the mesenteric microvascular endothelium, in vivo, as a consequence of hemorrhagic shock and reperfusion, and to correlate this ROS production to leukocyte adherence. Following a control period, blood was withdrawn to reduce the mean arterial pressure to 40 mmHg for 1 h in urethane-anesthetized rats. Mesenteric venules in a transilluminated segment of small intestine were examined to quantitate changes in ROS generation and leukocyte adherence. Sprague-Dawley rats were injected with dihydrorhodamine 123, a hydroperoxide-sensitive fluorescent probe that is trapped within viable cells as a nonfluorescent form and then converted to the mitochondrion-selective form rhodamine 123 by hydroperoxides. The fluorescent light emission from rhodamine 123 was recorded with digital microscopy and downloaded to a computerized image analysis program. Our results demonstrated an 80% increase in ROS generation beginning within 5 min into resuscitation and a 10-fold increase in leukocyte adherence that occurred at 10 min after resuscitation. Both ROS generation and leukocyte adherence were attenuated with pre-shock administration of platelet activating factor (PAF) antagonist, WEB 2086, and the CD11/CD18a antibody, anti-LFA-1beta. Our findings suggest that ROS production in endothelial cells is increased during reperfusion following hemorrhagic shock and that the mechanism of expression is mediated in part by both PAF expression and subsequent leukocyte adherence.

Radical scavenging activity of extruded corn gruels with addition of linden inflorescence

“…Extracts rich in phenolic compounds can be used as medicines or preventive agents protecting humans and animals from the destructive action of free radicals [11][12][13]. Reactive oxygen species (ROS) have been implicated in many pathological conditions, including rheumatoid arthritis [14], hemorrhagic shock [15], cardiomyopathy [16] and gastrointestinal ischemia [17]. High concentration of ROS leads to destruction of cell membranes, proteins, and nucleic acids, which is dangerous because it may lead to carcinoma formation [18,19].…”

Resveratrol Restores Sirtuin 1 (SIRT1) Activity and Pyruvate Dehydrogenase Kinase 1 (PDK1) Expression after Hemorrhagic Injury in a Rat Model

“…Mitochondrial functional decline results in decreased ATP production, fatty acid oxidation and increased reactive oxygen species (ROS), and mitochondrially generated ROS may lead to further mitochondrial dysfunction (13)(14)(15). When cellular oxygen availability decreases, mitochondrial oxidation is suppressed and glycolysis is promoted (16).…”

Resveratrol Improves Cardiac Contractility following Trauma-Hemorrhage by Modulating Sirt1

“…The predominant causes for mortality following hemorrhagic shock are sepsis and multiple organ failure (10). Among the major biochemical mediators implicated in tissue injury following hemorrhagic shock/resuscitation are reactive oxygen species (ROS) (11)(12)(13). ROS mediate immune alteration and mitochondrial damage, the latter initiating a vicious cycle generating more ROS.…”