Objectives: To identify novel approaches to improve innate immunity in the lung following trauma complicated by hemorrhagic shock (T/HS) for prevention of nosocomial pneumonia.
Methods: We developed a rat model of T/HS followed by Pseudomonas aeruginosa (PA) pneumonia to assess the effect of alveolar epithelial cell (AEC) apoptosis, and its prevention by IL-6, on lung surfactant protein (SP)-D protein levels, lung bacterial burden, and survival from PA pneumonia, as well as to determine whether AEC apoptosis is a consequence of the unfolded protein response (UPR). Lung UPR transcriptome analysis was performed on rats subjected to sham, T/HS, and T/HS plus IL-6 protocols.
Trauma complicated by hemorrhagic shock (T/HS) is the leading cause of morbidity and mortality in the United States for individuals under the age of 44 years. Initial survivors are susceptible to developing multiple organ failure (MOF), which is thought to be caused, at least in part, by excessive or maladaptive activation of inflammatory pathways. We previously demonstrated in rodents that T/HS results in liver injury that can be prevented by IL-6 administration at the start of resuscitation; however, the contribution of the severity of HS to the extent of liver injury, whether or not resuscitation is required, and the mechanism(s) for the IL-6 protective effect have not been reported.
View Article and Find Full Text PDFAcute lung injury (ALI) occurs in up to 37% of patients following trauma/hemorrhagic shock (T/HS) and, in other settings, is due to alveolar epithelial cell (AEC) apoptosis. To determine if AEC apoptosis is a key contributor to ALI following T/HS and whether or not signal transducer and activator of translation (Stat)3 activation can prevent it, rats were pretreated with a Stat3 inhibitor or placebo and subjected to T/HS or sham protocol and resuscitated without or with interleukin (IL)-6. T/HS induced apoptosis in up to 15% of lung cells, 82% of which were AEC.
View Article and Find Full Text PDFTrauma is a major cause of mortality in the United States. Death among those surviving the initial insult is caused by multiple organ failure (MOF) with the liver among the organs most frequently affected. We previously demonstrated in rodents that trauma complicated by hemorrhagic shock (trauma/HS) results in liver injury that can be prevented by IL-6 administration at the start of resuscitation; however, the contribution of the severity of HS to the extent of liver injury, whether or not resuscitation is required and the mechanism for the IL-6 protective effect have not been reported.
View Article and Find Full Text PDFCryptosporidiosis, caused by the protozoan parasite Cryptosporidium parvum, causes self-limited diarrhea in normal hosts but can cause life-threatening diarrhea for immunosuppressed patients. There is an urgent need for new drugs to treat this chronic disease. Cryptosporidium parvum infection is associated with intestinal structural and pathophysiologic changes, including villi blunting and glucose malabsorption.
View Article and Find Full Text PDFHalf of trauma deaths are attributable to hypovolemic circulatory collapse (HCC). We established a model of HCC in rats involving minor trauma plus severe hemorrhagic shock (HS). HCC in this model was accompanied by a 50% reduction in peak acceleration of aortic blood flow and cardiomyocyte apoptosis.
View Article and Find Full Text PDFCryptosporidiosis, caused by the protozoan parasite Cryptosporidium, causes self-limited diarrhea in immunocompetent hosts and severe life-threatening diarrhea in AIDS patients. Highly active antiretroviral therapy has been used to effectively treat cryptosporiosis in some but not all AIDS patients. Therefore, there is an urgent need for innovative drugs to treat this disease.
View Article and Find Full Text PDFPlatelets are known to contribute to ischemia/reperfusion in several organs, but their role in inflammation and organ injury after hemorrhagic shock (HS) has not been examined. To address this issue, we rendered mice thrombocytopenic (20% of normal platelet count) by treatment with pOp3, a rat monoclonal antibody against platelet glycoprotein Ibalpha, 24 h before subjecting them to either a standard HS or sham protocol. Liver apoptosis increased 3- to 5-fold (P<0.
View Article and Find Full Text PDFObjective: Intrauterine exposure to hyperthermia at term is associated with adverse neonatal neurologic outcomes. The objective of this study was to determine whether prophylactic maternal corticosteroid treatment prevents fetal exposure to hyperthermia and inflammatory cytokines after epidural analgesia.
Study Design: A 2-phase, randomized, institutional review board-approved, double-blind, placebo-controlled trial was performed.
Background: Resuscitation from hemorrhagic shock (HS) predisposes to subsequent infections. Susceptibility to infection following sepsis has been attributed to apoptosis. Interleukin (IL)-6 has been shown to have antiapoptotic properties and to decrease postresuscitation inflammation in rodent and porcine models of HS.
View Article and Find Full Text PDFIn mammalian heterochromatin, cytosine bases of CpG dinucleotides are symmetrically modified by methylation. Patterns of CpG methylation are maintained by the action of Dnmt1, the mammalian maintenance cytosine methyltransferase enzyme. We genetically manipulated the levels of CpG methylation and found that extensive chromatin alterations occur in pericentric heterochromatin.
View Article and Find Full Text PDFChronic ethanol use preceding severe trauma and hemorrhagic shock (HS) is associated with an increased incidence of multiorgan failure (MOF) and death; however, the molecular basis for this increased susceptibility is unknown. We previously demonstrated that production of interleukin-6 (IL-6) and granulocyte colony-stimulating factor (G-CSF), mediated by nuclear factor-kappa B (NF-kappa B), each make essential contributions to organ injury and inflammation in a rodent model of controlled HS, and we proposed in this study to examine the hypothesis that the increased susceptibility to MOF after shock/trauma in the setting of chronic ethanol use is due to an exaggerated activation of NF-kappa B and production of these proinflammatory cytokines. We observed increased HS-induced liver injury 4 h after resuscitation in rats fed the ethanol-containing Lieber-DeCarli liquid diet for 8 weeks compared with rats fed the control liquid diet (3-fold increase in serum alanine aminotransferase [ALT], P = 0.
View Article and Find Full Text PDFStat3 is an Src homology (SH)2-containing protein constitutively activated in a wide variety of human cancers following its recruitment to YXXQ-containing motifs, which results in resistance to apoptosis. Despite resolution of the crystal structure of Stat3 homodimer bound to DNA, the structural basis for the unique specificity of Stat3 SH2 for YXXQ-containing phosphopeptides remains unresolved. We tested three models of this interaction based on computational analysis of available structures and sequence alignments, two of which assumed an extended peptide configuration and one in which the peptide had a beta-turn.
View Article and Find Full Text PDFThe patterns of transcription and translation of the ribosomal protein L32 (Rpl32) mRNA differ greatly in adult testis and somatic tissues. Northern blots reveal that the levels of Rpl32 mRNA are four- to five-fold higher in prepubertal and adult testes, and purified pachytene spermatocytes and round spermatids than in a variety of nongrowing adult somatic tissues. 5' RACE demonstrates that transcription in 8-day prepubertal testis, which lacks meiotic and haploid cells, strongly prefers the same start site in the 5' terminal oligopyrimidine tract (5' TOP) that is used is somatic cells.
View Article and Find Full Text PDFIntroduction: Hypotension causes diffuse liver injury accompanied by increased local production of interleukin-6 (IL-6) in swine models of uncontrolled hemorrhagic shock (HS). IL-6 is transcriptionally up-regulated by nuclear factor (NF)-kappaB and results in activation of signal transducer and activator of transcription-3 (Stat3) in a murine model of controlled HS. Our objectives were: 1).
View Article and Find Full Text PDFBiallelic expression of Igf2 is frequently seen in cancers because Igf2 functions as a survival factor. In many tumors the activation of Igf2 expression has been correlated with de novo methylation of the imprinted region. We have compared the intrinsic susceptibilities of the imprinted region of Igf2 and H19, other imprinted genes, bulk genomic DNA, and repetitive retroviral sequences to Dnmt1 overexpression.
View Article and Find Full Text PDF