MOF, MODS, and SIRS: what is in a name or an acronym?

A new sight to acute pancreatitis through paracolic gutter exudation, a multicenter retrospective study

Objectives

Paracolic gutter exudation (PGE) may influence the severity of acute pancreatitis, but no study has explored it extensively. The objective of this study was to evaluate PGE for assessing the severity of disease.

Methods

We performed a retrospective analysis of 488 patients from three tertiary hospitals in Guangxi, China. General clinical information, severity, and clinical courses were recorded. The PGE score were classified as follows: 0 for no exudation, 1 for unilateral exudation, and 2 for bilateral exudation. We used ROC curves to assess the predictive value of the PGE score, and logistic regression analysis to determine risk factors associated with death, ICU admission, and the occurrence of MODS.

Results

This study included 352 patients with moderately severe acute pancreatitis (MSAP) and 136 patients with severe acute pancreatitis (SAP). Patients who had PGE experienced higher total hospitalization costs, longer hospital stays, a higher incidence of SAP, higher mortality rates, higher ICU admission rates, a higher incidence of MODS, and higher incidence of infections than those without (P < 0.05). Diagnostic efficacy in predicting severity in patients with MSAP and SAP increased after BISAP, MCTSI, modified Marshall, and SOFA scores combined with PGE score respectively. The PGE score of >1 is an independent risk factor for ICU admission and MODS occurrence. (P < 0.05).

Conclusion

The PGE provides reliable and objective information for assessing severity and clinical course of patients with MSAP and SAP.

Sex disparities in adverse outcomes after surgically managed isolated traumatic spinal injury

BACKGROUND

Traumatic spinal injury (TSI) encompasses a wide range of injuries affecting the spinal cord, nerve roots, bones, and soft tissues that result in pain, impaired mobility, paralysis, and death. There is some evidence suggesting that women may have different physiological responses to traumatic injury compared to men; therefore, this study aimed to investigate if there are any associations between sex and adverse outcomes following surgically managed isolated TSI.

METHODS

Using the 2013-2019 TQIP database, all adult patients with isolated TSI, defined as a spine AIS ≥ 2 with an AIS ≤ 1 in all other body regions, resulting from blunt force trauma requiring spinal surgery, were eligible for inclusion in the study. The association between the sex and in-hospital mortality as well as cardiopulmonary and venothromboembolic complications was determined by calculating the risk ratio (RR) after adjusting for potential confounding using inverse probability weighting.

RESULTS

A total of 43,756 patients were included. After adjusting for potential confounders, female sex was associated with a 37% lower risk of in-hospital mortality [adjusted RR (95% CI): 0.63 (0.57-0.69), p < 0.001], a 27% lower risk of myocardial infarction [adjusted RR (95% CI): 0.73 (0.56-0.95), p = 0.021], a 37% lower risk of cardiac arrest [adjusted RR (95% CI): 0.63 (0.55-0.72), p < 0.001], a 34% lower risk of deep vein thrombosis [adjusted RR (95% CI): 0.66 (0.59-0.74), p < 0.001], a 45% lower risk of pulmonary embolism [adjusted RR (95% CI): 0.55 (0.46-0.65), p < 0.001], a 36% lower risk of acute respiratory distress syndrome [adjusted RR (95% CI): 0.64 (0.54-0.76), p < 0.001], a 34% lower risk of pneumonia [adjusted RR (95% CI): 0.66 (0.60-0.72), p < 0.001], and a 22% lower risk of surgical site infection [adjusted RR (95% CI): 0.78 (0.62-0.98), p < 0.032], compared to male sex.

CONCLUSION

Female sex is associated with a significantly decreased risk of in-hospital mortality as well as cardiopulmonary and venothromboembolic complications following surgical management of traumatic spinal injuries. Further studies are needed to elucidate the cause of these differences.

Protective and therapeutic potential of melatonin against intestinal diseases: updated review of current data based on molecular mechanisms

INTRODUCTION

Intestinal diseases, a leading global cause of mortality and morbidity, carry a substantial socioeconomic burden. Small and large intestines play pivotal roles in gastrointestinal physiology and food digestion. Pathological conditions, such as gut dysbiosis, inflammation, cancer, therapy-related complications, ulcers, and ischemia, necessitate the urgent exploration of safe and effective complementary therapeutic strategies for optimal intestinal health.

AREAS COVERED

This article evaluates the potential therapeutic effects of melatonin, a molecule with a wide range of physiological actions, on intestinal diseases including inflammatory bowel disease, irritable bowel syndrome, colon cancer, gastric/duodenal ulcers and other intestinal disorders.

EXPERT OPINION

Due to anti-inflammatory and antioxidant properties as well as various biological actions, melatonin could be a therapeutic option for improving digestive disorders. However, more researches are needed to fully understand the potential benefits and risks of using melatonin for digestive disorders.

The Consequences of Aging On the Response to Injury and Critical Illness

Changing demographic trends have led to an increase in the overall geriatric trauma patient volume. Furthermore, the intersection of aging and injury can be problematic because geriatric patients have multiple comorbidities, geriatric-specific syndromes, and reduced physiological reserve. Despite mounting evidence that frail geriatric patients have inferior outcomes following trauma, very few studies have examined the effect of aging on the biological response to injury. In the present article, we review the current literature and explore the pathophysiological rationale underlying observed data, available evidence, and future directions on this topic.

Alarming Cargo: The Role of Exosomes in Trauma-Induced Inflammation

Severe polytraumatic injury initiates a robust immune response. Broad immune dysfunction in patients with such injuries has been well-documented; however, early biomarkers of immune dysfunction post-injury, which are critical for comprehensive intervention and can predict the clinical course of patients, have not been reported. Current circulating markers such as IL-6 and IL-10 are broad, non-specific, and lag behind the clinical course of patients. General blockade of the inflammatory response is detrimental to patients, as a certain degree of regulated inflammation is critical and necessary following trauma. Exosomes, small membrane-bound extracellular vesicles, found in a variety of biofluids, carry within them a complex functional cargo, comprised of coding and non-coding RNAs, proteins, and metabolites. Composition of circulating exosomal cargo is modulated by changes in the intra- and extracellular microenvironment, thereby serving as a homeostasis sensor. With its extensively documented involvement in immune regulation in multiple pathologies, study of exosomal cargo in polytrauma patients can provide critical insights on trauma-specific, temporal immune dysregulation, with tremendous potential to serve as unique biomarkers and therapeutic targets for timely and precise intervention.

Trauma induces expansion and activation of a memory-like Treg population

CD4+ regulatory T cells (Tregs) are acutely activated by traumatic injury, which suggests that they may react to injury with similar kinetics as memory T cells. Here, we used a mouse burn trauma model to screen for memory-like T cell responses to injury by transferring T cells from sham or burn CD45.1 mice into CD45.2 mice and performing secondary injuries in recipient mice. Among all T cell subsets that were measured, only Tregs expanded in response to secondary injury. The expanded Tregs were a CD44high /CD62Llow subpopulation, markers indicative of memory T cells. CyTOF (cytometry by time-of-flight) mass cytometry was used to demonstrate that injury-expanded Tregs expressed higher levels of CD44, CTLA-4, ICOS, GITR, and Helios than Tregs from noninjured mice. Next, we tested whether a similar population of Tregs might react acutely to burn trauma. We observed that Tregs with a phenotype that matched the injury-expanded Tregs were activated by 6 h after injury. To test if Treg activation by trauma requires functional MHC class II, we measured trauma-induced Treg activation in MHC class II gene deficient (MHCII-/- ) mice or in mice that were given Fab fragment of anti-MHC class II antibody to block TCR activation. Injury-induced Treg activation occurred in normal mice but only partial activation was detected in MHCII-/- mice or in mice that were given Fab anti-MHCII antibody. These findings demonstrate that trauma activates a memory-like Treg subpopulation and that Treg activation by injury is partially dependent on TCR signaling by an MHC class II dependent mechanism.

Sepsis Definitions in Burns

Background: Sepsis is the leading cause of death in burns. Despite its importance, sepsis lacks a proper definition. An established definition will lead to early and accurate diagnosis, prompt treatment, and a reduced mortality rate. The aim of this work is to discuss current definitions and to look ahead at novel definitions with clinical implications. Method: A review of the current understanding of sepsis definitions in burns. Results: Adaptation of sepsis definitions in the general population and specific burn definitions have gotten better but still need improvements and, potentially, incorporation of molecular, laboratory, patient-specific, and clinical factors. This work includes the history, evolution, and predictive value of current definitions of sepsis in burns. A review of current and future markers of sepsis and potentially useful definitions are presented. Conclusions: Sepsis definitions have evolved over the last decades and will continue to do so. We believe the best definition in burn patients is the Sepsis-3 that was developed originally for critically ill patients. However, there are several studies investigating more specific definitions with better sensitivity and specificity.

Preoperative TruCulture® whole blood cytokine response predicts post-operative inflammation in pancreaticoduodenectomy patients-A pilot cohort study

Major surgery is associated with substantial morbidity and mortality with early post-operative adverse events (POAE) occurring in 30% of patients within the first 30 days. The underlying pathogenesis is multifactorial, including immune dysfunction and increased inflammatory response to surgery. We investigated preoperative immune function by the TruCulture® whole blood technique in a cohort of patients undergoing pancreaticoduodenectomy (PD), hypothesizing that patients developing inflammatory POAE defined as leucocytosis, fever or high (above median) area under the curve (AUC) C-reactive protein (CRP) the first post-operative week would display perturbed preoperative immune function. Sixty-two adult patients were screened, 30 included and 11 excluded post-inclusion due to other surgical procedures than PD and post-operative complications directly attributed to surgery, leaving 19 patients for analysis of preoperative immune function. Patients developing leucocytosis (n = 5, 26%) had lower Toll-like receptor (TLR)-3-stimulated IL-12p40 and higher Candida Albicans (TLR1/2/4/6, Dectin-1)-stimulated TNF-α, compared to patients without leucocytosis (all P < .05). Patients developing fever (n = 7, 37%) had lower TLR7/8-stimulated IFN-γ and patients with high AUC CRP (n = 9, 47%) had lower TLR3-stimulated IFN-γ and IL-6 and lower TLR7/8-stimulated IL-10 (all P < .05), compared to patients without fever or low CRP, respectively. In conclusion, patients with inflammatory POAE displayed lower preoperative stimulated IL-12p40, IFN-γ, IL-6 and IL-10 and higher TNF-α response, compared to patients without inflammatory POAE. This finding suggests that TruCulture is a feasible immunologic screening tool in surgical patients, with a potential for preoperative identification of patients at increased risk for inflammatory POAE, allowing for risk-based intervention trials.

Differential clinical benefits of continuous blood purification treatment in critically ill patients with variable APACHE II scores

The present study aimed to assess whether the Acute Physiology And Chronic Health Evaluation (APACHE) II score may be used to predict whether critically ill patients benefit from continuous blood purification (CBP) treatment. A total of 115 critically ill patients were retrospectively reviewed and grouped according to their baseline APACHE II scores. Each group was further divided into 2 groups based on whether they received CBP or not. At 72 h after CBP treatment, clinical indicators comprising the plasma levels of inflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-8, as well as endotoxin and procalcitonin (PCT), and severity scores (APACHE II, multiple organ dysfunction syndrome and systemic inflammatory response syndrome), were analyzed in all patients. It was observed that while CBP slightly reduced the severity scores in all patients, it significantly improved those in patients with an APACHE II score of 20-29 (P<0.05). Similarly, the plasma levels of TNF-α, IL-6, IL-8, endotoxin and PCT were significantly lower in patients receiving CBP than in those without CBP when the APACHE II score was 20-29 (P<0.05). Furthermore, CBP treatment significantly decreased the fatality rate and length of stay at the intensive care unit (ICU) for critically ill patients with an APACHE II score of 20-29 (P<0.05). In conclusion, CBP significantly decreases the inflammatory response, shortens the length of stay at the ICU and improves the prognosis for critically ill patients with an APACHE II score of 20-29 points. This observation suggests that the APACHE II score is an important clinical indicator to determine the potential benefit of CBP therapy in critically ill patients.

Describing organ dysfunction in the intensive care unit: a cohort study of 20,000 patients

BACKGROUND

Multiple organ dysfunction is a common cause of morbidity and mortality in intensive care units (ICUs). Original development of the Sequential Organ Failure Assessment (SOFA) score was not to predict outcome, but to describe temporal changes in organ dysfunction in critically ill patients. Organ dysfunction scoring may be a reasonable surrogate outcome in clinical trials but further exploration of the impact of case mix on the temporal sequence of organ dysfunction is required. Our aim was to compare temporal changes in SOFA scores between hospital survivors and non-survivors.

METHODS

We performed a population-based observational retrospective cohort study of critically ill patients admitted from January 1, 2004, to December 31, 2013, to 4 multisystem adult intensive care units (ICUs) in Calgary, Canada. The primary outcome was temporal changes in daily SOFA scores during the first 14 days of ICU admission. SOFA scores were modeled between hospital survivors and non-survivors using generalized estimating equations (GEE) and were also stratified by admission SOFA (≤ 11 versus > 11).

RESULTS

The cohort consisted of 20,007 patients with at least one SOFA score and was mostly male (58.2%) with a median age of 59 (interquartile range [IQR] 44-72). Median ICU length of stay was 3.5 (IQR 1.7-7.5) days. ICU and hospital mortality were 18.5% and 25.5%, respectively. Temporal change in SOFA scores varied by survival and admission SOFA score in a complicated relationship. Area under the receiver operating characteristic (ROC) curve using admission SOFA as a predictor of hospital mortality was 0.77. The hospital mortality rate was 5.6% for patients with an admission SOFA of 0-2 and 94.4% with an admission SOFA of 20-24. There was an approximately linear increase in hospital mortality for SOFA scores of 3-19 (range 8.7-84.7%).

CONCLUSIONS

Examining the clinical course of organ dysfunction in a large non-selective cohort of patients provides insight into the utility of SOFA. We have demonstrated that hospital outcome is associated with both admission SOFA and the temporal rate of change in SOFA after admission. It is necessary to further explore the impact of additional clinical factors on the clinical course of SOFA with large datasets.

Gender differences in trauma, shock and sepsis

Despite efforts in prevention and intensive care, trauma and subsequent sepsis are still associated with a high mortality rate. Traumatic injury remains the main cause of death in people younger than 45 years and is thus a source of immense social and economic burden. In recent years, the knowledge concerning gender medicine has continuously increased. A number of studies have reported gender dimorphism in terms of response to trauma, shock and sepsis. However, the advantageous outcome following trauma-hemorrhage in females is not due only to sex. Rather, it is due to the prevailing hormonal milieu of the victim. In this respect, various experimental and clinical studies have demonstrated beneficial effects of estrogen for the central nervous system, the cardiopulmonary system, the liver, the kidneys, the immune system, and for the overall survival of the host. Nonetheless, there remains a gap between the bench and the bedside. This is most likely because clinical studies have not accounted for the estrus cycle. This review attempts to provide an overview of the current level of knowledge and highlights the most important organ systems responding to trauma, shock and sepsis. There continues to be a need for clinical studies on the prevailing hormonal milieu following trauma, shock and sepsis.

Chronic Critical Illness and Persistent Inflammation: What can we Learn from the Elderly, Injured, Septic, and Malnourished?

Patients in the intensive care unit (ICU) who develop chronic critical illness significantly stress the clinical capacity and financial resources of healthcare systems. Although vast improvements have been made in critical care management, outcomes for this ICU subset remain poor. A hallmark for patients who progress to chronic critical illness is the development of persistent inflammation and immunosuppression. The risk factors associated with the development of chronic critical illness include increased age, medical comorbidities, severe injury, septic shock, and malnutrition. Interestingly, each of these clinical states bears strikingly similar immune defects, often resulting in the activation of a persistent inflammatory state. Strategies aimed at the prevention or early recognition of this state of immune compromise may help improve outcomes for these individuals and minimize the number who progress to chronic critical illness. This review explores the current knowledge regarding the immune defects associated with the development of persistent inflammation, the ways in which it can manifest clinically, attempted therapeutic interventions to date, and future insights into improving outcomes for this patient population.

Ringer's lactate solution enhances the inflammatory response during fluid resuscitation of experimentally induced haemorrhagic shock in rats

INTRODUCTION

Hemorrhagic shock leads to systemic oxygen deficit (hypoxaemia) that results in systemic inflammatory response syndrome (SIRS), a recognised cause of late mortality in this case. The aim of this study was to analyse the impact of fluid resuscitation, using two Ringer solutions, on the microcirculation changes that take place during experimentally induced haemorrhagic shock.

MATERIAL AND METHODS

A model of the rat cremaster muscle was used to assess microcirculation in vivo. The experimental groups (n = 10 each) included: control (CTRL); shock (HSG); Ringer's acetate (RAG); and Ringer's lactate (RLG). Microhaemodynamic parameters were measured during the experiment.

RESULTS

A statistically significantly higher level of leukocytes, both those attached to the endothelium and those located in the extravascular space (p < 0.05), was reported in the lactate Ringer (LR) group compared with the AR group. There were significant differences in the activity of A3 arterioles compared with A1 and A2 arterioles. Ringer's lactate solution seemed to the inflammation response during fluid resuscitation from haemorrhagic shock. A3 arterioles are likely to play a role as a pre-capillary sphincter in the skeletal muscle.

CONCLUSIONS

The present study revealed that fluid resuscitation with Ringer's lactate solution exacerbates inflammation in the skeletal muscle. It is worth noting that Ringer's acetate solution reduces local inflammation and could therefore be recommended as the "first line" crystalloid of the fluid resuscitation during haemorrhagic shock.

Shed Pleural Blood from Traumatic Hemothorax Contains Elevated Levels of Pro-Inflammatory Cytokines

PURPOSE

The autotransfusion of unwashed (or unprocessed) shed hemothorax blood (USHB) in trauma patients is widely assumed to be beneficial; however, the inflammatory potential of shed pleural blood has not been thoroughly studied. Since previous studies have documented marked changes in coagulation function of shed pleural blood, we hypothesized that its level of inflammatory cytokines would be elevated.

METHODS

A prospective observational study of trauma patients in whom cytokine levels from USHB were compared to venous samples from healthy volunteers was conducted. Differences between the cytokine content of patient-derived samples were compared to those from healthy subjects.

RESULTS

There was a statistically significant increase in pro-inflammatory cytokines (IL-6, IL-8, TNFα, GM-CSF), a pro-inflammatory Th-1 cytokine (IFNγ), and anti-inflammatory Th-2 cytokines (IL-4 and IL-10) in shed pleural blood over four hours when compared with samples from healthy controls (P <0.05). Cytokine levels in USHB are approximately 10- to 100-fold higher compared with healthy control venous samples.

CONCLUSIONS

USHB, even collected within the accepted four-hour window, contains significantly elevated cytokine levels, suggesting the potential for deleterious effects from autotransfusion. Randomized trials are needed to determine the safety and efficacy of autotransfusion in trauma patients.

The influence of sex steroid hormones on the response to trauma and burn injury

Trauma and related sequelae result in disturbance of homeostatic mechanisms frequently leading to cellular dysfunction and ultimately organ and system failure. Regardless of the type and severity of injury, gender dimorphism in outcomes following trauma have been reported, with females having lower mortality than males, suggesting that sex steroid hormones (SSH) play an important role in the response of body systems to trauma. In addition, several clinical and experimental studies have demonstrated the effects of SSH on the clinical course and outcomes following injury. Animal studies have reported the ability of SSH to modulate immune, inflammatory, metabolic and organ responses following traumatic injury. This indicates that homeostatic mechanisms, via direct and indirect pathways, can be maintained by SSH at local and systemic levels and hence result in more favourable prognosis. Here, we discuss the role and mechanisms by which SSH modulates the response of the body to injury by maintaining various processes and organ functions. Such properties of sex hormones represent potential novel therapeutic strategies and further our understanding of current therapies used following injury such as oxandrolone in burn-injured patients.

Defining multiple organ failure after major trauma: A comparison of the Denver, Sequential Organ Failure Assessment, and Marshall scoring systems

BACKGROUND

Postinjury multiple organ failure (MOF) remains a significant cause of morbidity and mortality. A large number of scoring systems have been proposed to define MOF, with no criterion standard. The purpose of this study was to compare three commonly used scores: the Denver Postinjury Multiple Organ Failure Score, the Sequential Organ Failure Assessment (SOFA), and the Marshall Multiple Organ Dysfunction Score, by descriptive analysis of the populations described by each score, and their predictive ability for mortality.

METHODS

An observational cohort study was performed at a UK trauma center on major trauma patients requiring intensive care unit admission from 2003 to 2011. A novel trauma database was created, merging national audit data with local electronic monitoring systems. Data were collected on demographics, laboratory results, pharmacy, interventions, and hourly physiological monitoring. The primary outcome measure was mortality within 100 days from injury. Sensitivity analyses and receiver operating characteristic curves were used to assess the predictive ability of MOF scores for mortality.

RESULTS

In total, 491 patients were included in the trauma database. MOF incidence ranged from 22.8% (Denver) to 40.5% (Marshall) to 58.5% (SOFA). MOF definition did not affect timing of onset, but did alter duration and organ failure patterns. Overall mortality was 10.6%, with Denver MOF associated with the greatest increased risk of death (hazard ratio 3.87, 95% confidence interval, 2.24-6.66). No significant difference was observed in area under the receiver operating characteristic curve values between scores. Marked differences were seen in relative predictors, with Denver showing highest specificity (81%) and SOFA highest sensitivity (73%) for mortality.

CONCLUSION

The choice of MOF scoring system affects incidence, duration, organ dysfunction patterns, and mortality prediction. We would recommend use of the Denver score since it is simplest to calculate, identifies a high-risk group of patients, and has the strongest association with early trauma mortality.

LEVEL OF EVIDENCE

Epidemiological study, level III.

Mitochondria-meditated pathways of organ failure upon inflammation

Liver failure induced by systemic inflammatory response (SIRS) is often associated with mitochondrial dysfunction but the mechanism linking SIRS and mitochondria-mediated liver failure is still a matter of discussion. Current hypotheses suggest that causative events could be a drop in ATP synthesis, opening of mitochondrial permeability transition pore, specific changes in mitochondrial morphology, impaired Ca²⁺ uptake, generation of mitochondrial reactive oxygen species (mtROS), turnover of mitochondria and imbalance in electron supply to the respiratory chain. The aim of this review is to critically analyze existing hypotheses, in order to highlight the most promising research lines helping to prevent liver failure induced by SIRS. Evaluation of the literature shows that there is no consistent support that impaired Ca⁺⁺ metabolism, electron transport chain function and ultrastructure of mitochondria substantially contribute to liver failure. Moreover, our analysis suggests that the drop in ATP levels has protective rather than a deleterious character. Recent data suggest that the most critical mitochondrial event occurring upon SIRS is the release of mtROS in cytoplasm, which can activate two specific intracellular signaling cascades. The first is the mtROS-mediated activation of NADPH-oxidase in liver macrophages and endothelial cells; the second is the acceleration of the expression of inflammatory genes in hepatocytes. The signaling action of mtROS is strictly controlled in mitochondria at three points, (i) at the site of ROS generation at complex I, (ii) the site of mtROS release in cytoplasm via permeability transition pore, and (iii) interaction with specific kinases in cytoplasm. The systems controlling mtROS-signaling include pro- and anti-inflammatory mediators, nitric oxide, Ca²⁺ and NADPH-oxidase. Analysis of the literature suggests that further research should be focused on the impact of mtROS on organ failure induced by inflammation and simultaneously providing a new theoretical basis for a targeted therapy of overwhelmed inflammatory response.

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Relationship between mitochondrial dysfunction and high lethality upon sepsis.

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Criteria to define critical for lethality mitochondrial dysfunction.

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ATP, calcium, mitochondrial ultrastructure and apoptosis, upon inflammation.

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Regulation of inflammatory processes by mitochondrial ROS.

Postinjury Inflammation and Organ Dysfunction

The development of organ dysfunction (OD) is related to the intensity and balance between trauma-induced simultaneous, opposite inflammatory responses. Early proinflammation via innate immune system activation may cause early OD, whereas antiinflammation, via inhibition of the adaptive immune system and apoptosis, may induce immunoparalysis, impaired healing, infections, and late OD. Patients discharged with low-level OD may develop the persistent inflammation-immunosuppression catabolism syndrome. Although the incidence of multiple organ failure has decreased over time, it remains morbid, lethal, and resource intensive. However, single OD, especially acute lung injury, remains frequent. Treatment is limited, and prevention remains the mainstay strategy.

Individual-specific principal component analysis of circulating inflammatory mediators predicts early organ dysfunction in trauma patients

PURPOSE

We hypothesized that early inflammation can drive, or impact, later multiple organ dysfunction syndrome (MODS), that patient-specific principal component analysis (PCA) of circulating inflammatory mediators could reveal conserved dynamic responses which would not be apparent from the unprocessed data, and that this computational approach could segregate trauma patients with regard to subsequent MODS.

METHODS

From a cohort of 472 blunt trauma survivors, 2 separate subcohorts of moderately/severely injured patients were studied. Multiple inflammatory mediators were assessed in serial blood samples in the first 24 hours postinjury. PCA of these time course data was used to derive patient-specific "inflammation barcodes," followed by hierarchical clustering to define patient subgroups. To define the generalizability of this approach, 2 different but overlapping Luminex kits were used.

RESULTS

PCA/hierarchical clustering of 24-hour Luminex data segregated the patients into 2 groups that differed significantly in their Marshall multiple organ dysfunction score on subsequent days, independently of the specific set of inflammatory mediators analyzed. Multiple inflammatory mediators and their dynamic networks were significantly different in the 2 groups in both patient cohorts, demonstrating that the groups were defined based on "core" early responses exhibit truly different dynamic inflammatory trajectories.

CONCLUSION

Identification of patient-specific "core responses" can lead to early segregation of diverse trauma patients with regard to later MODS. Hence, we suggest that a focus on dynamic inflammatory networks rather than individual biomarkers is warranted.

Scoring System for Multiple Organ Dysfunction in Adult Horses with Acute Surgical Gastrointestinal Disease

Background

The prevalence of multiple organ dysfunction syndrome (MODS) in horses with acute surgical gastrointestinal (GI) disease is unknown. Currently, there are no validated criteria to confirm MODS in adult horses.

Objectives

To develop criteria for a MODS score for horses with acute surgical colic (MODS SGI) and evaluate the association with 6‐month survival. To compare the MODS SGI score with a MODS score extrapolated from criteria used in people (MODS EQ).

Animals

Adult horses that required exploratory laparotomy (n = 62) for colic. Healthy adult horses undergoing elective surgical procedures (n = 12) established the reference range of some variables.

Methods

Prospectively, a MODS SGI score was developed based on organ‐specific criteria established from a literature review, data collection, and clinical judgment. Data for scoring each horse were collected on Days 1 and 2 postoperatively. Horses were scored retrospectively using both scoring criteria. The prognostic performance of the MODS SGI score and its overall performance compared with the MODS EQ score were assessed with receiver operating characteristic (ROC) curve analysis.

Results

The MODS SGI score had excellent performance for predicting 6‐month survival with an area under the ROC curve (AUC) of 0.95 (95% CI: 0.87–0.99). The AUC for the MODS SGI score was significantly higher than the MODS EQ (AUC: 0.76; 0.63–0.86).

Conclusions and Clinical Importance

The MODS SGI score predicts 6‐month survival from discharge in horses with acute surgical colic. The MODS SGI score performed better than a score extrapolated from human scoring systems.

Temporal trends of postinjury multiple-organ failure: still resource intensive, morbid, and lethal

BACKGROUND

While the incidence of postinjury multiple-organ failure (MOF) has declined during the past decade, temporal trends of its morbidity, mortality, presentation patterns, and health care resources use have been inconsistent. The purpose of this study was to describe the evolving epidemiology of postinjury MOF from 2003 to 2010 in multiple trauma centers sharing standard treatment protocols.

METHODS

"Inflammation and Host Response to Injury Collaborative Program" institutions that enrolled more than 20 eligible patients per biennial during the 2003 to 2010 study period were included. The patients were aged 16 years to 90 years, sustained blunt torso trauma with hemorrhagic shock (systolic blood pressure < 90 mm Hg, base deficit ≥ 6 mEq/L, blood transfusion within the first 12 hours), but without severe head injury (motor Glasgow Coma Scale [GCS] score < 4). MOF temporal trends (Denver MOF score > 3) were adjusted for admission risk factors (age, sex, body max index, Injury Severity Score [ISS], systolic blood pressure, and base deficit) using survival analysis.

RESULTS

A total of 1,643 patients from four institutions were evaluated. MOF incidence decreased over time (from 17% in 2003-2004 to 9.8% in 2009-2010). MOF-related death rate (33% in 2003-2004 to 36% in 2009-2010), intensive care unit stay, and mechanical ventilation duration did not change over the study period. Adjustment for admission risk factors confirmed the crude trends. MOF patients required much longer ventilation and intensive care unit stay, compared with non-MOF patients. Most of the MOF-related deaths occurred within 2 days of the MOF diagnosis. Lung and cardiac dysfunctions became less frequent (57.6% to 50.8%, 20.9% to 12.5%, respectively), but kidney and liver failure rates did not change (10.1% to 12.5%, 15.2% to 14.1%).

CONCLUSION

Postinjury MOF remains a resource-intensive, morbid, and lethal condition. Lung injury is an enduring challenge and should be a research priority. The lack of outcome improvements suggests that reversing MOF is difficult and prevention is still the best strategy.

LEVEL OF EVIDENCE

Epidemiologic study, level III.

Immune response to traumatic injury: harmony and discordance of immune system homeostasis

Trauma remains one of the leading causes of death worldwide. Traumatic injury disrupts immune system homeostasis and may predispose patients to opportunistic infections and inflammatory complications. Prevention of multiple organ dysfunction syndrome due to septic complications following severe trauma is a challenging problem. Following severe injury, the immune system usually tends toward a pro-inflammatory phenotype and then changes to a counter-inflammatory phenotype. This immune system homeostasis is believed to be a protective response based on the balance between the innate and adaptive immune systems. We reported that injury activates inflammasomes and primes Toll-like receptors. The primed innate immune system is prepared for a rapid and strong antimicrobial immune defense. However, trauma can also develop the "two-hit" response phenotype. We also reported that injury augments regulatory T cell activity, which can control the "two-hit" response phenotype in trauma. We discuss the current idea that traumatic injury induces a unique type of innate and adaptive immune response that may be triggered by damage-associated molecular pattern molecules, which are a combination of endogenous danger signal molecules that include alarmins and pathogen-associated molecular pattern molecules.

The key role of nitric oxide in hypoxia: hypoxic vasodilation and energy supply-demand matching

SIGNIFICANCE

A mismatch between energy supply and demand induces tissue hypoxia with the potential to cause cell death and organ failure. Whenever arterial oxygen concentration is reduced, increases in blood flow--hypoxic vasodilation--occur in an attempt to restore oxygen supply. Nitric oxide (NO) is a major signaling and effector molecule mediating the body's response to hypoxia, given its unique characteristics of vasodilation (improving blood flow and oxygen supply) and modulation of energetic metabolism (reducing oxygen consumption and promoting utilization of alternative pathways).

RECENT ADVANCES

This review covers the role of oxygen in metabolism and responses to hypoxia, the hemodynamic and metabolic effects of NO, and mechanisms underlying the involvement of NO in hypoxic vasodilation. Recent insights into NO metabolism will be discussed, including the role for dietary intake of nitrate, endogenous nitrite (NO₂⁻) reductases, and release of NO from storage pools. The processes through which NO levels are elevated during hypoxia are presented, namely, (i) increased synthesis from NO synthases, increased reduction of NO₂⁻ to NO by heme- or pterin-based enzymes and increased release from NO stores, and (ii) reduced deactivation by mitochondrial cytochrome c oxidase.

CRITICAL ISSUES

Several reviews covered modulation of energetic metabolism by NO, while here we highlight the crucial role NO plays in achieving cardiocirculatory homeostasis during acute hypoxia through both vasodilation and metabolic suppression.

FUTURE DIRECTIONS

We identify a key position for NO in the body's adaptation to an acute energy supply-demand mismatch.

Evaluation of Serum Creatine Kinase and Urinary Myoglobin as Markers in Detecting Development of Acute Renal Failure in Severely Injured Trauma Patients

Background. Presence of myoglobinuria, particularly in the early phases of renal failure, and elevation of creatinine kinase are seen to correlate with the development of acute renal failure. Aim. To evaluate the efficiency of serum creatine kinase (CK) and urine myoglobin in assessing development of renal failure. Materials and Method. We prospectively studied trauma patients over a period of 3 months. Samples of 107 patients were routinely analyzed on the 1st, 3rd, and 5th days post trauma, for myoglobinuria and serum CK concentration. Results. 107 patients with median age 28 (4–83) yrs were studied, of which 83.2% were males. 56% had head injury, and 17.1% had high injury severity (ISS > 24). Incidence of renal failure was 9.3%. Myoglobinuria was present in 57 patients on admission, 33 on 3rd day and 22 on the 5th day. The association of myoglobinuria with renal failure was statistically insignificant. The cutoff values of serum CK on the 1st, 3rd, and 5th days were ≥1320 IU/L, ≥1146 IU/L, and ≥1754 IU/L, respectively. Mortality rate was 24 (22.4%), of which 6 had renal failure. Conclusion. Myoglobin is clinically insignificant in the detection of renal failure; serum CK is a sensitive predicting marker for the progression of renal failure following traumatic injury.

Incidence, clinical predictors and outcome of acute renal failure among North Indian trauma patients

Context:

There is a need for identifying risk factors aggravating development of acute renal failure after attaining trauma and defining new parameters for better assessment and management. Aim of the study was to determine the incidence of acute renal failure among trauma patients, and its correlation with various laboratory and clinical parameters recorded at the time of admission and in-hospital mortality.

Subjects and Methods:

The retrospective cohort study included admitted 208 trauma patients over a period of one year. 135 trauma patients at the serum creatinine level >2.0 mg/dL were enrolled in under the group of acute renal failure. 73 patients who had normal creatinine level made the control group. They were further assessed with clinical details and laboratory investigations.

Results:

Incidence of acute renal failure was 3.1%. There were 118 (87.4%) males and average length of stay was 9 (1, 83) days. Severity of injury (ISS, GCS) was relatively more among the renal failure group. Renal failure was transient in 35 (25.9%) patients. They had higher incidence of bone fracture (54.0%) (P= 0.04). Statistically significant association was observed between patients with head trauma and mortality 72 (59.0%) (P= 0.001). Prevalence of septic 24 (59.7%) and hemorrhagic 9 (7.4%) shock affected the renal failure group.

Conclusion:

Trauma patients at the urea level >50 mg/dL, ISS >24 on the first day of admission had 23 times and 7 times the risk of developing renal failure. Similarly, patients with hepatic dysfunction and pulmonary dysfunction were 12 times and 6 times. Patients who developed cardiovascular dysfunction, hematological dysfunction and post-trauma renal failure during the hospital stay had risk for mortality 29, 7 and 8 times, respectively. The final prognostic score obtained was: 14*hepatic dysfunction + 11*cISS + 18*cUrea + 12*cGlucose + 10*pulmonary dysfunction. Optimal score cut-off for prediction of renal failure was found to be ≥25 with specificity, sensitivity and positive likelihood ratio to be 84.9%, 78.4% and 3.9, respectively.

Hyperglycaemia, inflammation, RAS activation: three culprits to blame for acute kidney injury emerging in healthy rats during general anaesthesia

AIM

Major surgery under general anaesthesia might evoke acute kidney injury (AKI), sometimes culminating in end stage renal disease. We investigated the roles of hyperglycaemia, inflammation and renin-angiotensin system (RAS) activation in induction of AKI following anaesthesia by different anaesthetic drugs and/or regimens.

METHODS

Ninety-four Sprague-Dawley rats underwent 1 h-anaesthesia by various protocols, including repeated blood glucose and insulin measurements. Blood samples and kidneys were allocated at sacrifice, for evaluation of renal function, inflammatory status and Angiotensin-II availability.

RESULTS

Hyperglycaemia emerged in unconscious rats irrespective of anaesthetic drug choice or anaesthesia regimen. Insulin increase correlated with hyperglycaemia levels. Levels of Cystatin-C, as well as serum and urine neutrophil gelatinase-associated lipocain (NGAL), were significantly augmented. Serum transforming growth factor beta (TGF-β) and interleukins (IL)-1β, -4, -6, and -10 were significantly increased. Intra-renal Angiotensin-II, TGF-β, IL-6 and-10 were significantly increased. IL-1 was decreased. IL-4 remained unaltered.

CONCLUSIONS

Acute hyperglycaemia, systemic and intra-renal inflammation and RAS activation were independently triggered by induction of anaesthesia. Each confounder aggravated the impacts of the others, bringing about concomitant deterioration of renal function. Increased insulin secretion attenuated but did not abolish hyperglycaemia. Systemic inflammation was counterforced by anti-inflammatory cytokines, whereas intra-renal inflammation persisted, so that AKI progressed unopposed.

Burn-injury affects gut-associated lymphoid tissues derived CD4+ T cells

After scald burn-injury, the intestinal immune system responds to maintain immune balance. In this regard CD4+T cells in Gut-Associated Lymphoid Tissues (GALT), like mesenteric lymph nodes (MLN) and Peyer's patches (PP) respond to avoid immune suppression following major injury such as burn. Therefore, we hypothesized that the gut CD4+T cells become dysfunctional and turn the immune homeostasis towards depression of CD4+ T cell-mediated adaptive immune responses. In the current study we show down regulation of mucosal CD4+ T cell proliferation, IL-2 production and cell surface marker expression of mucosal CD4+ T cells moving towards suppressive-type. Acute burn-injury lead to up-regulation of regulatory marker (CD25+), down regulation of adhesion (CD62L, CD11a) and homing receptor (CD49d) expression, and up-regulation of negative co-stimulatory (CTLA-4) molecule. Moreover, CD4+CD25+ T cells of intestinal origin showed resistance to spontaneous as well as induced apoptosis that may contribute to suppression of effector CD4+ T cells. Furthermore, gut CD4+CD25+ T cells obtained from burn-injured animals were able to down-regulate naïve CD4+ T cell proliferation following adoptive transfer of burn-injured CD4+CD25+ T cells into sham control animals, without any significant effect on cell surface activation markers. Together, these data demonstrate that the intestinal CD4+ T cells evolve a strategy to promote suppressive CD4+ T cell effector responses, as evidenced by enhanced CD4+CD25+ T cells, up-regulated CTLA-4 expression, reduced IL-2 production, tendency towards diminished apoptosis of suppressive CD4+ T cells, and thus lose their natural ability to regulate immune homeostasis following acute burn-injury and prevent immune paralysis.

Role of complement in multiorgan failure

Multiorgan failure (MOF) represents the leading cause of death in patients with sepsis and systemic inflammatory response syndrome (SIRS) following severe trauma. The underlying immune response is highly complex and involves activation of the complement system as a crucial entity of innate immunity. Uncontrolled activation of the complement system during sepsis and SIRS with in excessive generation of complement activation products contributes to an ensuing dysfunction of various organ systems. In the present review, mechanisms of the inflammatory response in the development of MOF in sepsis and SIRS with particular focus on the complement system are discussed.

Activation of myocardial phosphoinositide-3-kinase p110α ameliorates cardiac dysfunction and improves survival in polymicrobial sepsis

Phosphoinositide-3-kinase (PI3K)/Akt dependent signaling has been shown to improve outcome in sepsis/septic shock. There is also ample evidence that PI3K/Akt dependent signaling plays a crucial role in maintaining normal cardiac function. We hypothesized that PI3K/Akt signaling may ameliorate septic shock by attenuating sepsis-induced cardiac dysfunction. Cardiac function and survival were evaluated in transgenic mice with cardiac myocyte specific expression of constitutively active PI3K isoform, p110α (caPI3K Tg). caPI3K Tg and wild type (WT) mice were subjected to cecal ligation/puncture (CLP) induced sepsis. Wild type CLP mice showed dramatic cardiac dysfunction at 6 hrs. Septic cardiomyopathy was significantly attenuated in caPI3K CLP mice. The time to 100% mortality was 46 hrs in WT CLP mice. In contrast, 80% of the caPI3K mice survived at 46 hrs after CLP (p<0.01) and 50% survived >30 days (p<0.01). Cardiac caPI3K expression prevented expression of an inflammatory phenotype in CLP sepsis. Organ neutrophil infiltration and lung apoptosis were also effectively inhibited by cardiac PI3k p110α expression. Cardiac high mobility group box–1 (HMGB-1) translocation was also inhibited by caPI3K p110α expression. We conclude that cardiac specific activation of PI3k/Akt dependent signaling can significantly modify the morbidity and mortality associated with sepsis. Our data also indicate that myocardial function/dysfunction plays a prominent role in the pathogenesis of sepsis and that maintenance of cardiac function during sepsis is essential. Finally, these data suggest that modulation of the PI3K/p110α signaling pathway may be beneficial in the prevention and/or management of septic cardiomyopathy and septic shock.

Protective role of p70S6K in intestinal ischemia/reperfusion injury in mice

The mTOR signaling pathway plays a crucial role in the regulation of cell growth, proliferation, survival and in directing immune responses. As the intestinal epithelium displays rapid cell growth and differentiation and is an important immune regulatory organ, we hypothesized that mTOR may play an important role in the protection against intestinal ischemia reperfusion (I/R)-induced injury. To better understand the molecular mechanisms by which the mTOR pathway is altered by intestinal I/R, p70S6K, the major effector of the mTOR pathway, was investigated along with the effects of rapamycin, a specific inhibitor of mTOR and an immunosuppressant agent used clinically in transplant patients. In vitro experiments using an intestinal epithelial cell line and hypoxia/reoxygenation demonstrated that overexpression of p70S6K promoted cell growth and migration, and decreased cell apoptosis. Inhibition of p70S6K by rapamycin reversed these protective effects. In a mouse model of gut I/R, an increase of p70S6K activity was found by 5 min and remained elevated after 6 h of reperfusion. Inhibition of p70S6K by rapamycin worsened gut injury, promoted inflammation, and enhanced intestinal permeability. Importantly, rapamycin treated animals had a significantly increased mortality. These novel results demonstrate a key role of p70S6K in protection against I/R injury in the intestine and suggest a potential danger in using mTOR inhibitors in patients at risk for gut hypoperfusion.

Continuous veno-venous hemodiafiltration alleviates multiple organ dysfunction syndrome in dogs

CONTEXT

Multiple organ dysfunction syndrome (MODS) is a major cause of death in critically patients. It has been hypothesized that inactivation or removal of pro-inflammatory molecules may prevent or reverse MODS.

OBJECTIVE

The purpose of this paper was to investigate the efficacy of continuous veno-venous hemodiafiltration (CVVHDF) as treatment for MODS in an established animal model.

MATERIALS AND METHODS

Male Beagle dogs (n = 18) were used to establish the model and were randomly assigned to a CVVHDF, sham, or control group. The serum levels of ALT, AST, Cr, BUN, PaO(2), and PaCO(2) were measured as functional makers of major organs. Apoptosis, DLA-DR expression, and cytokine levels of peripheral monocytes were determined.

RESULTS

The MODS model was successfully established. After CVVHDF treatment, the WBC and neutrophil counts were lower and the monocyte count and percentage were greater, but these were unchanged in the sham and control groups. Apoptosis of CD14+ monocytes was significantly lower in the CVVHDF group than in the sham and control groups. The fraction of DLA-DR(+) monocytes and IL-1β secretion was significantly greater in the sham and control groups than in the CVVHDF group. Moreover, IL-4 secretion increased significantly in the CVVHDF group but not in the control group.

DISCUSSION AND CONCLUSION

Our study of an experimental model of MODS indicated that MODS leads to significant disruption of physiological and immune functions. CVVHDF treatment alleviated some of these symptoms due to the improvement of monocyte function, reduction of monocyte apoptosis, and increase of anti-inflammatory cytokines.

Shock - A reappraisal: The holistic approach

Shock as reaction to life-threatening condition needs to be reclassified in a timely and more scientific synopsis. It is not possible or beneficial any longer to avoid a holistic approach in critical illness. Semantics of critical illness has often been unfriendly in the literature and a simplification with the elimination of conceptual pleonasms and misnomers under the exclusive light of physiology and physiopathology would be advantageous. Speaking one language to describe the same phenomenon worldwide is essential for understanding; moreover, it increases focus on characterization and significance of the phenomena.

Melanocortins as potential therapeutic agents in severe hypoxic conditions

Melanocortin peptides with the adrenocorticotropin/melanocyte-stimulating hormone (ACTH/MSH) sequences and synthetic analogs have protective and life-saving effects in experimental conditions of circulatory shock, myocardial ischemia, ischemic stroke, traumatic brain injury, respiratory arrest, renal ischemia, intestinal ischemia and testicular ischemia, as well as in experimental heart transplantation. Moreover, melanocortins improve functional recovery and stimulate neurogenesis in experimental models of cerebral ischemia. These beneficial effects of ACTH/MSH-like peptides are mostly mediated by brain melanocortin MC(3)/MC(4) receptors, whose activation triggers protective pathways that counteract the main ischemia/reperfusion-related mechanisms of damage. Induction of signaling pathways and other molecular regulators of neural stem/progenitor cell proliferation, differentiation and integration seems to be the key mechanism of neurogenesis stimulation. Synthesis of stable and highly selective agonists at MC(3) and MC(4) receptors could provide the potential for development of a new class of drugs for a novel approach to management of severe ischemic diseases.

Improvement of sepsis by hepatocyte growth factor, an anti-inflammatory regulator: emerging insights and therapeutic potential

Sepsis-induced multiple organ failure (MOF) is the most frequent lethal disease in intensive care units. Thus, it is important to elucidate the self-defensive mechanisms of sepsis-induced MOF. Hepatocyte growth factor (HGF) is now recognized as an organotrophic factor, which is essential for organogenesis during embryonic growth and regeneration in adulthood. HGF production is enhanced in response to infectious challenges, but the increase in endogenous HGF levels is transient and insufficient, with a time lag between tissue injuries and HGF upregulation, during progression of septic MOF. Thus, administration of active-formed HGF might be a new candidate for therapeutic development of MOF. HGF has an ability to target endotoxin-challenged macrophages and inhibits the upregulation of inflammatory cytokines through nuclear factor-κB-inactivated mechanisms. HGF also targets the endothelium and epithelium of various organs to suppress local inflammation, coagulation, and apoptotic death. This paper summarizes the novel mechanisms of HGF for attenuating sepsis-related pathological conditions with a focus on sepsis-induced MOF.

Clinical pathology of the shock syndromes

The clinical aspects of shock syndromes are described from their inception as compensated physiology to a stage of decompensation. The clinical significance of hypotension, fluid-responsive and non fluid-responsive hypotension, is discussed. Untimely or inadequate treatment leads to persistent subclinical shock despite adjustments of the macrohemodynamic variables, which evolves in a second hit of physiological deterioration if not aggressively managed. Irreversible shock ensues as consequence of direct hit or as result of inadequate or delayed treatment and is characterized by drug-resistant hypotension.

Survival trends and predictors of mortality in severe pelvic trauma: estimates from the German Pelvic Trauma Registry Initiative

STUDY OBJECTIVE

To determine longitudinal trends in mortality, and the contribution of specific injury characteristics and treatment modalities to the risk of a fatal outcome after severe and complex pelvic trauma.

METHODS

We studied 5048 patients with pelvic ring fractures enrolled in the German Pelvic Trauma Registry Initiative between 1991 and 1993, 1998 and 2000, and 2004 and 2006. Complete datasets were available for 5014 cases, including 508 complex injuries, defined as unstable fractures with severe peri-pelvic soft tissue and organ laceration. Multivariable mixed-effects logistic regression analysis was employed to evaluate the impact of demographic, injury- and treatment-associated variables on all-cause in-hospital mortality.

RESULTS

All-cause in-hospital mortality declined from 8% (39/466) in 1991 to 5% (33/638) in 2006. Controlling for age, Injury Severity Score, pelvic vessel injury, the need for emergency laparotomy, and application of a pelvic clamp, the odds ratio (OR) per annum was 0.94 (95% confidence interval [CI] 0.91-0.96). However, the risk of death did not decrease significantly in patients with complex injuries (OR 0.98, 95% CI 0.93-1.03). Raw mortality associated with this type of injury was 18% (95% CI 9-32%) in 2006.

CONCLUSION

In contrast to an overall decline in trauma mortality, complex pelvic ring injuries remain associated with a significant risk of death. Awareness of this potentially life-threatening condition should be increased amongst trauma care professionals, and early management protocols need to be implemented to improve the survival prognosis.

The heat shock paradox and cardiac myocytes: role of heat shock factor

The induction of the heat shock (HS) response is accepted to be a protective response, reducing injury and improving cell survival. However, when inflammation precedes HS, there is an unexpected increase in injury, known as the HS paradox, which is hypothesized to be a mechanism underlying multiorgan dysfunction. We hypothesized that the HS paradox would occur in adult cardiac myocytes and that HS factor (HSF) 1 would contribute to injury. Heat shock at 42°C and TNF (10 ng/mL) were used as the HS and the inflammatory insult, respectively. The combination of TNF followed by HS (TNF/HS) caused the greatest amount of apoptosis in adult rat cardiac myocytes. TNF/HS resulted in an increase in HS protein (HSP) 60, compared with untreated cells, those receiving HS/TNF, or TNF alone. There was no increase in heme oxygenase 1 in any of the groups. Heat shock protein 72 increased in all the groups, with the greatest levels with TNF/HS. Nuclear factor κB activation was greatest with TNF/HS. Pretreatment with a DNA-binding decoy for HSF-1 prevented the increase in HSPs and decreased apoptosis in all groups. However, the increase in iNOS, seen in all treatment groups, was unaffected by the HSF-1-binding decoy. We conclude that the HS paradox occurs in adult cardiac myocytes, that HSP60 is increased as part of the HS paradox, and that HSF-1 activation contributes to injury.

Imbalance between macrophage migration inhibitory factor and cortisol induces multiple organ dysfunction in patients with blunt trauma

Migration inhibitory factor (MIF) is associated with multiple organ dysfunction syndrome (MODS) in patients with systemic inflammatory response syndrome (SIRS). Our purposes were to determine the serum MIF, cortisol, and tumor narcosis factor-α (TNF-α) and to investigate the influences of the balance between the levels of MIF and cortisol in patients with blunt trauma. The cortisol levels were identical between the patients with and without MODS. However, the MIF and TNF-α levels in the patients with MODS were statistically higher than those of the patients without MODS. The cortisol/MIF ratios in the patients with MODS were statistically higher than those of the patients without MODS. The results show that MIF and TNF-α play an important role together in posttraumatic inflammatory response. An excessive serum MIF elevation overrides the anti-inflammatory effects of cortisol and leads to persistent SIRS followed by MODS in blunt trauma patients.

Melanocortins protect against multiple organ dysfunction syndrome in mice

BACKGROUND AND PURPOSE

Melanocortins reverse circulatory shock and improve survival by counteracting the systemic inflammatory response, and through the activation of the vagus nerve-mediated cholinergic anti-inflammatory pathway. To gain insight into the potential therapeutic value of melanocortins against multiple organ damage following systemic inflammatory response, here we investigated the effects of the melanocortin analogue [Nle⁴ D-Phe⁷]α-MSH (NDP-α-MSH) in a widely used murine model of multiple organ dysfunction syndrome (MODS).

EXPERIMENTAL APPROACH

MODS was induced in mice by a single intraperitoneal injection of lipopolysaccharide followed, 6 days later (= day 0), by zymosan. After MODS or sham MODS induction, animals were randomized to receive intraperitoneally NDP-α-MSH (340 µg·kg⁻¹ day) or saline for up to 16 days. Additional groups of MODS mice were concomitantly treated with the melanocortin MC₄ receptor antagonist HS024, or the nicotinic acetylcholine receptor antagonist chlorisondamine, and NDP-α-MSH.

KEY RESULTS

At day 7, in the liver and lung NDP-α-MSH, significantly reduced mRNA expression of tumour necrosis factor-α (TNF-α), increased mRNA expression of interleukin-10 and improved the histological picture, as well as reduced TNF-α plasma levels; furthermore, NDP-α-MSH dose-dependently increased survival rate, as assessed throughout the 16 day observation period. HS024 and chlorisondamine prevented all the beneficial effects of NDP-α-MSH in MODS mice.

CONCLUSIONS AND IMPLICATIONS

These data indicate that NDP-α-MSH protects against experimental MODS by counteracting the systemic inflammatory response, probably through brain MC₄ receptor-triggered activation of the cholinergic anti-inflammatory pathway. These findings reveal previously undescribed effects of melanocortins and could have clinical relevance in the MODS setting.

Aging influences cardiac mitochondrial gene expression and cardiovascular function following hemorrhage injury

Cardiac dysfunction and mortality associated with trauma and sepsis increase with age. Mitochondria play a critical role in the energy demand of cardiac muscles, and thereby on the function of the heart. Specific molecular pathways responsible for mitochondrial functional alterations after injury in relation to aging are largely unknown. To further investigate this, 6- and 22-month-old rats were subjected to trauma-hemorrhage (T-H) or sham operation and euthanized following resuscitation. Left ventricular tissue was profiled using our custom rodent mitochondrial gene chip (RoMitochip). Our experiments demonstrated a declined left ventricular performance and decreased alteration in mitochondrial gene expression with age following T-H and we have identified c-Myc, a pleotropic transcription factor, to be the most upregulated gene in 6- and 22-month-old rats after T-H. Following T-H, while 142 probe sets were altered significantly (39 up and 103 down) in 6-month-old rats, only 66 were altered (30 up and 36 down) in 22-month-old rats; 36 probe sets (11 up and 25 down) showed the same trend in both groups. The expression of c-Myc and cardiac death promoting gene Bnip3 were increased, and Pgc1-α and Ppar-α a decreased following T-H. Eleven tRNA transcripts on mtDNA were upregulated following T-H in the aged animals, compared with the sham group. Our observations suggest a c-myc-regulated mitochondrial dysfunction following T-H injury and marked decrease in age-dependent changes in the transcriptional profile of mitochondrial genes following T-H, possibly indicating cellular senescence. To our knowledge, this is the first report on mitochondrial gene expression profile following T-H in relation to aging.

Regulatory T cells suppress antigen-driven CD4 T cell reactivity following injury

Injury initiates local and systemic host responses and is known to increase CD4 Treg activity in mice and humans. This study uses a TCR transgenic T cell adoptive transfer approach and in vivo Treg depletion to determine specifically the in vivo influence of Tregs on antigen-driven CD4 T cell reactivity following burn injury in mice. We report here that injury in the absence of recipient and donor Tregs promotes high antigen-driven CD4 T cell expansion and increases the level of CD4 T cell reactivity. In contrast, CD4 T cell expansion and reactivity were suppressed significantly in injured Treg-replete mice. In additional experiments, we found that APCs prepared from burn- or sham-injured, Treg-depleted mice displayed significantly higher antigen-presenting activity than APCs prepared from normal mice, suggesting that Tregs may suppress injury responses by controlling the intensity of APC activity. Taken together, these findings demonstrate that Tregs can actively control the in vivo expansion and reactivity of antigen-stimulated, naïve CD4 T cells following severe injury.

Upregulation of TLR2/4 expression in mononuclear cells in postoperative systemic inflammatory response syndrome after liver transplantation

BACKGROUND

To explore the relationship between Toll-like rpheral blood mononuclear cells (PBMC) and systemic inflammatory response syndrome (SIRS) in postoperative patients of liver transplantation (LT).

METHODS

Blood samples of 27 patients receiving LT were collected at T1 (after induction of anaesthesia), T2 (25 minutes after the beginning of anhepatic phase), T3 (3 hours after graft reperfusion), and T4 (24 hours after graft reperfusion). The expression of TLR2/4 on PBMC and serum concentration of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and IL-8 were measured. The patients were divided into SIRS group (n = 12) and non-SIRS group (n = 15) for analysis.

RESULTS

Blood loss and transfusion were higher in the SIRS group than in the non-SIRS group. Both the preanhepatic and anhepatic phase were significantly longer in the SIRS group. The TLR2/4 expression on PBMC as well as serum TNF-alpha, IL-1beta, and IL-8 were significantly higher at T3 and T4 than that at T1 and T2 in the SIRS patients. The expression of TLR4 on PBMC is positively correlated to serum TNF-alpha, IL-8. Expression of TLR2/4 on PBMC and serum concentrations of TNF-alpha, IL-1beta, did not differ among the 4-time points in non-SIRS patients.

CONCLUSIONS

Upregulation of TLR2/4 expression on PBMC may contribute to the development of postoperative SIRS during perioperative period of LT.

Salutary effects of 17beta-estradiol on Peyer's patch T cell functions following trauma-hemorrhage

Although 17beta-estradiol (E2) administration following trauma-hemorrhage (T-H) improves immune functions in male rodents, it remains unclear whether E2 has salutary effects on Peyer's patch (PP) T cell functions. We hypothesized that T-H induces PP T cell dysfunction and E2 administration following T-H will improve PP T cell function. T-H was induced in male C3H/HeN mice (6-8weeks) by midline laparotomy and approximately 90min of hemorrhagic shock (blood pressure 35mmHg), followed by fluid resuscitation (4x the shed blood volume in the form of Ringer's lactate). Estrogen receptor (ER)-alpha agonist propyl pyrazole triol (PPT; 5microg/kg), ER-beta agonist diarylpropionitrile (DPN; 5microg/kg), E2 (50microg/kg), or vehicle was injected subcutaneously at resuscitation onset. Two hours later, mice were sacrificed and PP T cells isolated. PP T cell capacity to produce cytokines in response to in vitro stimulation, PP T cell proliferation and MAPK (p38, ERK-1/2, JNK) activation were measured. Results indicate PP T cell proliferation, cytokine production and MAPK activation decreased significantly following T-H. E2, PPT or DPN administration normalized these parameters. Since PPT or DPN administration following T-H was effective in normalizing PP T cell functions, the salutary effects of E2 are mediated via ER-alpha and ER-beta.

Human intestinal ischemia-reperfusion-induced inflammation characterized: experiences from a new translational model

Human intestinal ischemia-reperfusion (IR) is a frequent phenomenon carrying high morbidity and mortality. Although intestinal IR-induced inflammation has been studied extensively in animal models, human intestinal IR induced inflammatory responses remain to be characterized. Using a newly developed human intestinal IR model, we show that human small intestinal ischemia results in massive leakage of intracellular components from ischemically damaged cells, as indicated by increased arteriovenous concentration differences of intestinal fatty acid binding protein and soluble cytokeratin 18. IR-induced intestinal barrier integrity loss resulted in free exposure of the gut basal membrane (collagen IV staining) to intraluminal contents, which was accompanied by increased arteriovenous concentration differences of endotoxin. Western blot for complement activation product C3c and immunohistochemistry for activated C3 revealed complement activation after IR. In addition, intestinal IR resulted in enhanced tissue mRNA expression of IL-6, IL-8, and TNF-alpha, which was accompanied by IL-6 and IL-8 release into the circulation. Expression of intercellular adhesion molecule-1 was markedly increased during reperfusion, facilitating influx of neutrophils into IR-damaged villus tips. In conclusion, this study for the first time shows the sequelae of human intestinal IR-induced inflammation, which is characterized by complement activation, production and release of cytokines into the circulation, endothelial activation, and neutrophil influx into IR-damaged tissue.