. Pyruvate improves redox status and decreases indicators of hepatic apoptosis during hemorrhagic shock in swine. Am J Physiol Heart Circ Physiol 283: H1634-H1644, 2002. First published June 20, 2002 10.1152/ ajpheart.01073.2001.-Previous studies have shown that the liver is the first organ to display signs of injury during hemorrhagic shock. We examined the mechanism by which pyruvate can prevent liver damage during hemorrhagic shock in swine anesthetized with halothane. Thirty minutes after the induction of a 240-min controlled arterial hemorrhage targeted at 40 mmHg, hypertonic sodium pyruvate (0.5 g ⅐ kg Ϫ1 ⅐ h Ϫ1 ) was infused to achieve an arterial concentration of 5 mM. The volume and osmolality effects of pyruvate were matched with 10% saline (HTS) and 0.9% saline (NS). Although the peak hemorrhage volume increased significantly in both the pyruvate and HTS group, only the pyruvate treatment was effective in delaying cardiovascular decompensation. In addition, pyruvate effectively maintained the NADH/NAD redox state, as evidenced by increased microdialysate pyruvate levels and a significantly lower lactateto-pyruvate ratio. Pyruvate also prevented the loss of intracellular antioxidants (GSH) and a reduction in the GSH-to-GSSG ratio. These beneficial effects on the redox environment decreased hepatic cellular death by apoptosis. Pyruvate significantly increased the ratio of Bcl-Xl (antiapoptotic molecule)/Bax (proapoptotic molecule), prevented the release of cytochrome c from mitochondria, and decreased the fragmentation of caspase 3 and poly(ADP ribose) polymerase (DNA repair enzyme). These beneficial findings indicate that pyruvate infused 30 min after the onset of severe hemorrhagic shock is effective in maintaining the redox environment, preventing the loss of the key antioxidant GSH, and decreasing early apoptosis indicators. glutathione; redox state; caspases DESPITE ADVANCES IN THE EARLY CARE of trauma victims over the past two decades, multiple organ failure (MOF) continues to be a major factor in the morbidity and mortality that occurs after resuscitation from hemorrhagic shock (16). While there are numerous factors that influence the development of MOF, there is increasing evidence that hepatic dysfunction plays a central role (21,24,42,43). Experimental studies have shown that despite acute aggressive resuscitation, there is a consistent depression in microvascular blood flow that results in hypoperfusion and progressive hepatic dysfunction (32,42,43). This suggests that despite the restoration of global oxygen delivery, additional pharmacological therapies are needed to prevent or reverse ongoing hepatotoxicity. However, the precise mechanisms of hepatocellular dysfunction after severe hemorrhagic shock are not well defined. Some investigators have shown that the reduction in immunological mediators, such as tumor necrosis factor-␣, improves outcome indicators (23,41). Others have shown that there is severe hepatic energy depletion during hemorrhagic shock and that improvement in the hepatoce...
These data suggest that modulation of mitochondrial metabolic functions is likely to be one of the important mechanisms by which pyruvate exerts its protective effects on the liver during HS and resuscitation in rats.
Breast Cancer is the most common form of cancer in women worldwide, impacting nearly 2.1 million women each year. Identification of new biomarkers could be key for early diagnosis and detection. Vitronectin, a glycoprotein that is abundantly found in serum, extracellular matrix, and bone, binds to integrin αvβ3, and promotes cell adhesion and migration. Current studies indicate that patients with amplified vitronectin levels have lower survival rates than patients without amplified vitronectin levels. In this study, we focused on the role of vitronectin in breast cancer survival and its functional role as a non-invasive biomarker for early stage and stage specific breast cancer detection. To confirm that the expression of vitronectin is amplified in breast cancer, a total of 240 serum samples (n = 240), 200 from breast cancer patients and 40 controls were analyzed using the Reverse Phase Protein Array (RPPA) technique. Of the 240 samples, 120 samples were of African American (AA) descent, while the other 120 were of White American (WA) descent. Data indicated that there were some possible racial disparities in vitronectin levels and, differences also seen in the recurrent patient samples. Next, we tried to uncover the underlying mechanism which plays a critical role in vitronectin expression. The cellular data from four different breast cancer cell lines- MCF7, MDA-MB-231, MDA-MB-468, and HCC1599 indicated that the PI3K/AKT axis is modulating the expression of vitronectin. We believe that vitronectin concentration levels are involved and connected to the metastasis of breast cancer in certain patients, specifically based on recurrence or ethnicity, which is detrimental for poor prognosis. Therefore, in this current study we showed that the serum vitronectin levels could be an early marker for the breast cancer survival and we also determine the cellular signaling factors which modulate the expression and concentration of vitronectin.
The data indicate that profound KATP activation associated with increased nitric oxide concentrations and inducible nitric oxide synthase induction is a key factor in vascular smooth muscle hyporeactivity characteristic of the late decompensatory phase of hemorrhagic shock in swine.
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