Inflammation after ischemia and reperfusion (I/R) injury secondary to hemorrhagic shock is responsible for significant mortality and morbidity in the United States. Available intravenous fluids administered at the incident scene to treat hypovolemic shock do not completely prevent ischemia and reperfusion injury. Re- initiation of blood flow causes activation of several inflammatory mediators of the cytokine type, selectins and other molecules that rapidly mobilize the inflammatory response with subsequent global organ damage. The goal of the proposed project is to prevent or reduce the deleterious effects of ischemic damage following resuscitation by optimizing the anti-inflammatory properties of the hypertonic saline (HS)(7.5%) resuscitation solution. The approach is based on the utilization of the anti-ischemic and anti-inflammatory anti-selectin compound OC-229 developed by our laboratory, which blocks adhesion molecules such as P-, L-, and E-selectins, 1, 2-, and 4 integrins, vascular adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) and of a nitroso pyrimidyl substance (EC-234) that acts as a nitric oxide donor. Our hypothesis is that this combination fluid will effectively regulate leukocyte recruitment and overcome the inflammatory and ischemic response by modulating undesirable molecular signaling pathways. In this regard, we have clearly demonstrated in several studies that following treatment with anti- selectins, the impaired physiological circulatory parameters of animals with HS were significantly improved and the survival was significantly increased in treated animals as compared to control. We propose to demonstrate, in a non-heparinized hybrid model of controlled-uncontrolled hemorrhagic shock resuscitation in the rat, an accepted model to study hypovolemic shock, that a small volume of 4 ml/kg of HS combined with anti-ischemic compounds OC-229 and/or EC-234, will: 1) have a meaningful protective physiopathologic response to hemorrhage/hypovolemia by improving the end points of mean arterial pressure, arterial blood gases and liver function response, and 2) improve protection as determined by animal survival seen at 3-7 days after hemorrhagic shock. The study will also assess the response of the molecular pathways associated with hemorrhage and improved treatment. A phase II study will further characterize the anti-inflammatory signaling mechanisms associated with the effect of the solution, and study tissue distribution, cytotoxicity, and evaluation of the physiological response to the optimal combination dose of the resuscitation fluid in a pig military-relevant model.
