Shock : molecular, cellular, and systemic pathobiological aspects and therapeutic approaches : the official journal the Shock Society, the European Shock Society, the Brazilian Shock Society, the International Federation of Shock Societies
-
Sepsis following surgical injury remains a growing and worrisome problem following both emergent and elective surgery. Although early resuscitation efforts and prompt antibiotic therapy have improved outcomes in the first 24 to 48 h, late onset sepsis is now the most common cause of death in modern intensive care units. ⋯ Colonizing pathogens can then subvert the immune system and contribute to the deterioration of the host response. Here, we posit that novel approaches integrating the molecular, ecological, and evolutionary dynamics of the evolving gut microbiome/pathobiome during critical illness are needed to understand and prevent the late onset sepsis that develops following prolonged critical illness.
-
There is currently no effective treatment for multiorgan failure following shock other than supportive care. A better understanding of the pathogenesis of these sequelae to shock is required. The intestine plays a central role in multiorgan failure. ⋯ These proteases have the ability to clip the ectodomain of surface receptors and compromise their function, for example cleaving the insulin receptor causing insulin resistance. The combination of digestive enzymes and cytotoxic fragments leaking into the central circulation causes cell and organ dysfunction, and ultimately may lead to complete organ failure and death. We summarize current evidence suggesting that enteral blockade of digestive enzymes inside the lumen of the intestine may serve to reduce acute cell and organ damage and improve survival in experimental shock.
-
Mitochondrial DNA (mtDNA) is a novel danger-associated molecular pattern that on its release into the extracellular milieu acts via toll-like receptor-9, a pattern recognition receptor of the immune system. We hypothesized that plasma mtDNA concentrations will be elevated in septic children, and these elevations are associated with an increase in the severity of illness. In a separate set of in vitro experiments, we test the hypothesis that exposing peripheral blood mononuclear cells (PBMC) to mtDNA activates the immune response and induces tumor necrosis factor (TNF) release. ⋯ The median concentrations of plasma mtDNA were significantly greater in patients with MOF as compared with patients without MOF (3.2E+05 (IQR 1.41E+05-1.08E+06) vs. 2.9E+04 (IQR 2.47E+04-5.43E+04) copies/μL). PBMCs treated with mtDNA demonstrated higher supernatant TNF levels as compared with control cells (6.5 ± 1.8 vs. 3.5 ± 0.5 pg/mL, P > 0.05). Our data suggest that plasma mtDNA is a novel danger-associated molecular pattern in pediatric sepsis and appears to be associated with MOF.
-
It has been previously shown that intestinal proteases translocate into the circulation during hemorrhagic shock and contribute to proteolysis in distal organs. However, consequences of this phenomenon have not previously been investigated using high-throughput approaches. Here, a shotgun label-free quantitative proteomic approach was utilized to compare the peptidome of plasma samples from healthy and hemorrhagic shock rats to verify the possible role of uncontrolled proteolytic activity in shock. ⋯ In total, 256 peptides were increased or present only in HS confirming a general increase in proteolytic activity in shock. Analysis of the proteases that potentially generated the identified peptides suggests that the larger relative contribution to the proteolytic activity in shock is due to chymotryptic-like proteases. These results provide quantitative confirmation that extensive, system-wide proteolysis is part of the complex pathologic phenomena occurring in hemorrhagic shock.
-
Serum neutrophil gelatinase associated lipocalin (sNGAL), a promising acute kidney injury (AKI) biomarker produced by renal and non-renal tissues, might be affected by sepsis. We evaluated sNGAL in zero glomerular filtration rate models [bilateral ureter obstruction (BUO) and bilateral nephrectomy (BiNx)] with subsequent cecal ligation and puncture (CLP)-induced sepsis in 6 to 8-week-old ICR mice. We found that sNGAL increased earlier than serum creatinine (Scr) in BiNx/BUO with and without CLP. ⋯ Serum interleukin (IL)-6 was increased and correlated with sNGAL in BiNx/BUO with and without sepsis. In summary, we demonstrated: sNGAL is an early AKI biomarker, which is not affected by sepsis; sNGAL is mainly produced by extrarenal sources as demonstrated by the comparable sNGAL in BiNx and BUO; the saturation of renal NGAL re-absorption in BUO is demonstrated by lower sNGAL in BUO at 1 to 18 h, but not at 36 h when compared with BiNx; and a correlation of sNGAL and IL-6 implied sNGAL is a good sepsis prognostic biomarker. Therefore, sNGAL is a more beneficial sepsis-AKI biomarker than Scr.