Multiple organ dysfunction syndrome: a narrative review

Acute Pancreatitis Associated with Atypical Bacterial Pneumonia: Systematic Literature Review

BACKGROUND

Extra-pulmonary features sometimes occur in association with atypical bacterial pneumonia and include neurologic manifestations, diarrhea, rashes, altered liver enzymes, or kidney injury, among other conditions. Acute pancreatitis has been associated with atypical pneumonias since 1973.

METHODS

We performed a systematic review of the literature in the Excerpta Medica, National Library of Medicine, and Web of Science databases. We retained 27 reports published between 1973 and 2022 describing subjects with an otherwise unexplained pancreatitis temporally associated with an atypical pneumonia.

RESULTS

The reports included 33 subjects (19 males, and 14 females; 8 children and 25 adults) with acute pancreatitis temporally associated with atypical pneumonia caused by Mycoplasma pneumoniae (n = 18), Legionella species (n = 14), or Coxiella burnetii (n = 1). Approximately 90% of patients (n = 29) concurrently presented with respiratory and pancreatic diseases. No cases associated with Chlamydophila pneumoniae, Chlamydophila psittaci, or Francisella species were found.

CONCLUSIONS

Acute pancreatitis has been associated with various infectious agents. The present review documents the association with atypical pneumonia induced by Mycoplasma pneumoniae, Legionella species, and Coxiella burnetii.

Is NMDA-Receptor-Mediated Oxidative Stress in Mitochondria of Peripheral Tissues the Essential Factor in the Pathogenesis of Hepatic Encephalopathy?

Background: Hepatic encephalopathy (HE) is a neuropsychiatric syndrome of increased ammonia-mediated brain dysfunction caused by impaired hepatic detoxification or when the blood bypasses the liver. Ammonia-activated signal transduction pathways of hyperactivated NMDA receptors (NMDAR) are shown to trigger a cascade of pathological reactions in the brain, leading to oxidative stress. NMDARs outside the brain are widely distributed in peripheral tissues, including the liver, heart, pancreas, and erythrocytes. To determine the contribution of these receptors to ammonia-induced oxidative stress in peripheral tissues, it is relevant to investigate if there are any ammonia-related changes in antioxidant enzymes and free radical formation and whether blockade of NMDARs prevents these changes. Methods: Hyperammonemia was induced in rats by ammonium acetate injection. Oxidative stress was measured as changes in antioxidant enzyme activities and O2•− and H2O2 production by mitochondria isolated from the tissues and cells mentioned above. The effects of the NMDAR antagonist MK-801 on oxidative stress markers and on tissue ammonia levels were evaluated. Results: Increased ammonia levels in erythrocytes and mitochondria isolated from the liver, pancreas, and heart of hyperammonemic rats are shown to cause tissue-specific oxidative stress, which is prevented completely (or partially in erythrocyte) by MK-801. Conclusions: These results support the view that the pathogenesis of HE is multifactorial and that ammonia-induced multiorgan oxidative stress-mediated by activation of NMDAR is an integral part of the disease and, therefore, the toxic effects of ammonia in НЕ may be more global than initially expected.

Efficacy and safety of plasma hemodiafiltration (PHDF) in pediatric patients with multiple organ dysfunction syndrome with shock and DIC: a preliminary study

Background

Multiple organ dysfunction syndrome is the leading cause of death in pediatric intensive care units and can be very critical when combined with shock and disseminated intravascular coagulation (DIC). Currently, there is no effective treatment. We developed a new hemodiafiltration (HDF) method called plasma HDF (PHDF) that uses fresh frozen plasma as replacement fluid and investigated the safety and efficacy of this treatment.

Methods

We enrolled critically ill children with (1) a Pediatric Logistic Organ Dysfunction 2 (PELOD-2) score ≥ 14, (2) a Japanese Ministry of Health and Welfare (JMHW) DIC score ≥ 7, (3) a vasoactive inotropic score (VIS) ≥ 10, and (4) a serum total protein concentration ≤ 5.0 g/dL. PHDF was performed for 5 h and then switched to continuous HDF. The primary endpoint was the 28-day mortality rate. Secondary endpoints included assessment of vital signs, blood test data, and fluid balance from PHDF start to day 7.

Results

Nine patients (four males and five females) between 3 days and 40 months of age, weighing 2.1–13 kg, met the inclusion criteria. Although the median PMR was 0.94 (0.71–0.96), the 28-day mortality rate was 22.2% (2/9). One hour after the start of PHDF, there was an increase in mean arterial pressure and central venous pressure and a decrease in heart rate; by day 7, there was a significant decrease in the PELOD-2 score, the JMHW DIC score, and the VIS. Hypoproteinemia also improved the day after PHDF. Water balance was able to remain negative after day 2.

Conclusions

PHDF was found to be effective in the treatment of DIC and circulatory failure by supplementing coagulation and antithrombotic factors as well as by raising colloid osmotic pressure to increase circulating blood volume. PHDF has been shown to be a safe and useful treatment for critically ill children and has the potential to improve 28-day survival.

Secondary Peritonitis and Intra-Abdominal Sepsis: An Increasingly Global Disease in Search of Better Systemic Therapies

Secondary peritonitis and intra-abdominal sepsis are a global health problem. The life-threatening systemic insult that results from intra-abdominal sepsis has been extensively studied and remains somewhat poorly understood. While local surgical therapy for perforation of the abdominal viscera is an age-old therapy, systemic therapies to control the subsequent systemic inflammatory response are scarce. Advancements in critical care have led to improved outcomes in secondary peritonitis. The understanding of the effect of secondary peritonitis on the human microbiome is an evolving field and has yielded potential therapeutic targets. This review of secondary peritonitis discusses the history, classification, pathophysiology, diagnosis, treatment, and future directions of the management of secondary peritonitis. Ongoing clinical studies in the treatment of secondary peritonitis and the open abdomen are discussed.

Myositis and acute kidney injury in bacterial atypical pneumonia: Systematic literature review

BACKGROUND

Bacterial community-acquired atypical pneumonia is sometimes complicated by a myositis or by a renal parenchymal disease. Available reviews do not mention the concurrent occurrence of both myositis and acute kidney injury.

METHODS

In order to characterize the link between bacterial community-acquired atypical pneumonia and both myositis and a renal parenchymal disease, we reviewed the literature (United States National Library of Medicine and Excerpta Medica databases).

RESULTS

We identified 42 previously healthy subjects (35 males and 7 females aged from 2 to 76, median 42 years) with a bacterial atypical pneumonia associated both with myositis (muscle pain and creatine kinase ≥5 times the upper limit of normal) and acute kidney injury (increase in creatinine to ≥1.5 times baseline or increase by ≥27 μmol/L above the upper limit of normal). Thirty-six cases were caused by Legionella species (N = 27) and by Mycoplasma pneumoniae (N = 9). Further germs accounted for the remaining 6 cases. The vast majority of cases (N = 36) presented a diffuse myalgia. Only a minority of cases (N = 3) were affected by a calf myositis. The diagnosis of rhabdomyolysis-associated kidney injury was retained in 37 and that of acute interstitial nephritis in the remaining 5 cases.

CONCLUSION

Bacterial atypical pneumonia may occasionally induce myositis and secondary kidney damage.

Quantifying the Autonomic Response to Stressors-One Way to Expand the Definition of "Stress" in Animals

Quantifying how whole organisms respond to challenges in the external and internal environment ("stressors") is difficult. To date, physiological ecologists have mostly used measures of glucocorticoids (GCs) to assess the impact of stressors on animals. This is of course too simplistic as Hans Seyle himself characterized the response of organisms to "noxious stimuli" using multiple physiological responses. Possible solutions include increasing the number of biomarkers to more accurately characterize the "stress state" of animal or just measuring different biomarkers to more accurately characterize the degree of acute or chronic stressors an animal is experiencing. We focus on the latter and discuss how heart rate (HR) and heart rate variability (HRV) may be better predictors of the degree of activation of the sympathetic-adrenal-medullary system and complement or even replace measures of GCs as indicators of animal health, welfare, fitness, or their level of exposure to stressors. The miniaturization of biological sensor technology ("bio-sensors" or "bio-loggers") presents an opportunity to reassess measures of stress state and develop new approaches. We describe some modern approaches to gathering these HR and HRV data in free-living animals with the aim that heart dynamics will be more integrated with measures of GCs as bio-markers of stress state and predictors of fitness in free-living animals.

Circulating miRNAs Associated With ER Stress and Organ Damage in a Preclinical Model of Trauma Hemorrhagic Shock

Circulating microRNAs (miRNA) alterations have been reported in severe trauma patients but the pathophysiological relevance of these changes is still unclear. miRNAs are critical biologic regulators of pathological events such as hypoxia and inflammation, which are known to induce endoplasmic reticulum (ER) stress. ER stress is emerging as an important process contributing to the development of single and/or multiple organ dysfunction after trauma hemorrhagic shock (THS) accompanied by impaired tissue microcirculation and inflammation. Here, we aim to bring new insights into the involvement of miRNAs associated with ER stress in THS. THS was induced in rats by a median laparotomy and blood withdrawal until mean arterial pressure (MAP) dropped to 30-35 mmHg followed by a restrictive (40 min) and full reperfusion (60 min) with Ringer's solution. Tunicamycin was used to induce ER stress. Blood samples were collected 24 h after THS for the determination of pathological changes in the blood (PCB) and circulating miRNAs. Plasma levels of circulating miRNAs were compared between THS, tunicamycin, and sham groups and correlated to biomarkers of PCB. MiRNA profile of THS animals showed that 40 out of 91 (44%) miRNAs were significantly upregulated compared to sham (p < 0.01). The data showed a very strong correlation between liver injury and miR−122-5p (r = 0.91, p < 0.00001). MiR-638, miR−135a-5p, miR−135b-5p, miR-668-3p, miR-204-5p, miR−146a-5p, miR−200a-3p, miR−17-5p, miR−30a-5p, and miR−214-3p were found positively correlated with lactate (r > 0.7, p < 0.05), and negatively with base excess (r ≤ 0.8, p < 0.05) and bicarbonate (r ≤ 0.8, p < 0.05), which are clinical parameters that reflected the shock severity. Tunicamycin significantly modified the microRNA profile of the animals, 33 out of 91 miRNAs were found differentially expressed. In addition, principal component analysis revealed that THS and tunicamycin induced similar changes in plasma miRNA patterns. Strikingly, the data showed that 15 (25.9%) miRNAs were regulated by both THS and tunicamycin (p < 0.01). This included miR−122-5p, a liver-specific microRNA, but also miR−17-5p and miR-125b-5p which are miRNAs remarkably involved in unfolded protein response (UPR)-mediating pro-survival signaling (IRE1α). Since miRNAs associated with ER stress are clearly correlated with THS, our data strongly suggest that interaction between miRNAs and ER stress is an important pathologic event occurring during THS. Overall, we consider that the miRNA profile developed in this study can provide a rationale for the development of bench-to-bedside strategies that target miRNAs in critical care diseases or be used as biomarkers in the prognosis of trauma patients.

Dihydromyricetin improves vascular hyporesponsiveness in experimental sepsis via attenuating the over-excited MaxiK and KATP channels

CONTEXT

Dihydromyricetin (DMY) has oxidation resistance, anti-inflammatory and free radical scavenging capabilities. The preventive effects of DMY for vascular hyporeactivity remain unclear.

OBJECTIVE

This study investigates the preventive effects of DMY in vascular hyporeactivity.

MATERIALS AND METHODS

The experimental sepsis was induced by transvenous administration of lipopolysaccharide (LPS) to Sprague-Dawley (SD) rats. DMY-treated rats received daily administration of DMY, 5 μg/kg dissolved in DMSO through the tail vein for 7 days. The invasive mean arterial pressure (MAP) of the caudal ventral artery was measured. Dose-response curves for norepinephrine (NE, doses from 10^-9 to 10^-6M) were obtained in isolated thoracic aorta in a cumulative manner. The function of MaxiK and K_ATP channels were investigated using whole-cell patch clamp recording. The Elisa was adopted to measure the serum concentration of NO, MDA, 3-NT, IL-1β and TNF-α.

RESULTS

The increased MAP in septic rats induced by vasopressor agents was smaller than that in control rats. However, the % of increased MAP induced by vasopressor agents was raised by DMY injection (NE: 20.4 ± 8.495 vs. 15.16 ± 5.195%; AVP: 14.05 ± 2.459 vs. 9.583 ± 2.982%, p < 0.05). The vascular hyporesponsiveness to NE (10^-6M) in vitro. was increased by 51% in LPS + DMY group compared with that in LPS + Con group (2.74 ± 0.81 vs. 1.82 ± 0.92 g, p < 0.05). Charybdotoxin (a potent MaxiK channel blocker) and glibenclamide (a K_ATP channel blocker) pretreatment, instead of 4-aminopyridine (4-AP) and BaCl₂, could diminish the DMY-induced improvement of vasoconstrictor hyporeactivity (ChTX: 73.2 ± 11.8 vs. 71.8 ± 13.5%; Glib: 63.1 ± 12.5 vs. 58.1 ± 13.7%, p > 0.05). DMY blunted the highly sensitized MaxiK and K_ATP channels of arterial smooth muscle cells isolated from the thoracic aorta of LPS rats. DMY decreased the serum level of NO, MDA, IL-1β and TNF-α, which had increased in LPS rats.

DISCUSSION AND CONCLUSIONS

Our results indicate that DMY administration ameliorated the impaired contractility of the rat aorta in experimental sepsis. Such an effect is mediated by normalization of the over-excited MaxiK and K_ATP, channels possibly via oxidative stress inhibition.

Closed Or Open after Source Control Laparotomy for Severe Complicated Intra-Abdominal Sepsis (the COOL trial): study protocol for a randomized controlled trial

Background

Severe complicated intra-abdominal sepsis (SCIAS) has an increasing incidence with mortality rates over 80% in some settings. Mortality typically results from disruption of the gastrointestinal tract, progressive and self-perpetuating bio-mediator generation, systemic inflammation, and multiple organ failure. Principles of treatment include early antibiotic administration and operative source control. A further therapeutic option may be open abdomen (OA) management with active negative peritoneal pressure therapy (ANPPT) to remove inflammatory ascites and ameliorate the systemic damage from SCIAS. Although there is now a biologic rationale for such an intervention as well as non-standardized and erratic clinical utilization, this remains a novel therapy with potential side effects and clinical equipoise.

Methods

The Closed Or Open after Laparotomy (COOL) study will constitute a prospective randomized controlled trial that will randomly allocate eligible surgical patients intra-operatively to either formal closure of the fascia or use of the OA with application of an ANPTT dressing. Patients will be eligible if they have free uncontained intra-peritoneal contamination and physiologic derangements exemplified by septic shock OR a Predisposition-Infection-Response-Organ Dysfunction Score ≥ 3 or a World-Society-of-Emergency-Surgery-Sepsis-Severity-Score ≥ 8. The primary outcome will be 90-day survival. Secondary outcomes will be logistical, physiologic, safety, bio-mediators, microbiological, quality of life, and health-care costs. Secondary outcomes will include days free of ICU, ventilation, renal replacement therapy, and hospital at 30 days from the index laparotomy. Physiologic secondary outcomes will include changes in intensive care unit illness severity scores after laparotomy. Bio-mediator outcomes for participating centers will involve measurement of interleukin (IL)-6 and IL-10, procalcitonin, activated protein C (APC), high-mobility group box protein-1, complement factors, and mitochondrial DNA. Economic outcomes will comprise standard costing for utilization of health-care resources.

Discussion

Although facial closure after SCIAS is considered the current standard of care, many reports are suggesting that OA management may improve outcomes in these patients. This trial will be powered to demonstrate a mortality difference in this highly lethal and morbid condition to ensure critically ill patients are receiving the best care possible and not being harmed by inappropriate therapies based on opinion only.

Trial registration

ClinicalTrials.gov, NCT03163095.

To What Extent Are the Terminal Stages of Sepsis, Septic Shock, Systemic Inflammatory Response Syndrome, and Multiple Organ Dysfunction Syndrome Actually Driven by a Prion/Amyloid Form of Fibrin?

A well-established development of increasing disease severity leads from sepsis through systemic inflammatory response syndrome, septic shock, multiple organ dysfunction syndrome, and cellular and organismal death. Less commonly discussed are the equally well-established coagulopathies that accompany this. We argue that a lipopolysaccharide-initiated (often disseminated intravascular) coagulation is accompanied by a proteolysis of fibrinogen such that formed fibrin is both inflammatory and resistant to fibrinolysis. In particular, we argue that the form of fibrin generated is amyloid in nature because much of its normal α-helical content is transformed to β-sheets, as occurs with other proteins in established amyloidogenic and prion diseases. We hypothesize that these processes of amyloidogenic clotting and the attendant coagulopathies play a role in the passage along the aforementioned pathways to organismal death, and that their inhibition would be of significant therapeutic value, a claim for which there is considerable emerging evidence.

Management of intra-abdominal infections: recommendations by the WSES 2016 consensus conference

This paper reports on the consensus conference on the management of intra-abdominal infections (IAIs) which was held on July 23, 2016, in Dublin, Ireland, as a part of the annual World Society of Emergency Surgery (WSES) meeting. This document covers all aspects of the management of IAIs. The Grading of Recommendations Assessment, Development and Evaluation recommendation is used, and this document represents the executive summary of the consensus conference findings.

Sepsis and septic shock: Pathogenesis and treatment perspectives

The majority of bacteremias do not develop to sepsis: bacteria are cleared from the bloodstream. Oxygen released from erythrocytes and humoral immunity kill bacteria in the bloodstream. Sepsis develops if bacteria are resistant to oxidation and proliferate in erythrocytes. Bacteria provoke oxygen release from erythrocytes to arterial blood. Abundant release of oxygen to the plasma triggers a cascade of events that cause: 1. oxygen delivery failure to cells; 2. oxidation of plasma components that impairs humoral regulation and inactivates immune complexes; 3. disseminated intravascular coagulation and multiple organs' failure. Bacterial reservoir inside erythrocytes provides the long-term survival of bacteria and is the cause of ineffectiveness of antibiotics and host immune reactions. Treatment perspectives that include different aspects of sepsis development are discussed.

Puerperal sepsis and maternal mortality: what role can new technologies play?

OBJECTIVE

To identify new and underutilized technologies to reduce maternal mortality related to puerperal sepsis in developing countries.

METHOD

Review of current medical literature.

RESULT

The literature indicates that infection-control protocols and evidence-based procedures--including prophylactic antibiotics for cesarean section or preterm rupture of membranes, and updated antibiotic regimens--should be widely adopted. Devices such as hand rubs, needle-disposal systems, and rapid microbiological diagnostic tests can improve compliance and efficiency. Operational research on promising developments like vaginal cleansing with antiseptics, vitamin A supplementation, and prophylactic antibiotics in high-risk women is needed.

CONCLUSION

Sepsis management continues to depend on good implementation of established technologies. Program-based approaches are required to improve uptake.

Organ protection during aortic cross-clamping

Open surgical repair of an aortic aneurysm requires aortic cross-clamping, resulting in temporary ischemia of all organs and tissues supplied by the aorta distal to the clamp. Major complications of open aneurysm repair due to aortic cross-clamping include renal ischemia-reperfusion injury and postoperative colonic ischemia in case of supra- and infrarenal aortic aneurysm repair. Ischemia-reperfusion injury results in excessive production of reactive oxygen species and in oxidative stress, which can lead to multiple organ failure. Several perioperative protective strategies have been suggested to preserve renal function during aortic cross-clamping, such as pharmacotherapy and therapeutic hypothermia of the kidneys. In this chapter, we will briefly discuss the pathophysiology of ischemia-reperfusion injury and the preventative measures that can be taken to avoid abdominal organ injury. Finally, techniques to minimize the risk of complications during and after open aneurysm repair will be presented.

Effect of Negative Pressure Therapy on the Inflammatory Response of the Intestinal Microenvironment in a Porcine Septic Model

In a swine model of ischemia/reperfusion injury coupled with sepsis, we have previously shown attenuation of secondary organ injury and decreased mortality with negative pressure therapy (NPT). We hypothesized that NPT modulates the intestinal microenvironment by mediating the innate immune system. Sepsis was induced in 12 anesthetized female pigs. Group 1 (n = 6) was decompressed at 12 hrs after injury (T₁₂) and treated with standard of care (SOC), and group 2 (n = 6) with NPT for up to T₄₈. Immunoparalysis was evident as lymphocytopenia at T₂₄ in both groups; however, survival was improved in the NPT group versus SOC (Odds ratio = 4.0). The SOC group showed significant reduction in lymphocyte numbers compared to NPT group by T₄₈ (p < 0.05). The capacity of peritoneal fluid to stimulate a robust reactive oxygen species response in vitro was greater for the NPT group, peaking at T₂₄ for both M1 (p = 0.0197) and M2 macrophages (p = 0.085). Plasma elicited little if any effect which was confirmed by microarray analysis. In this septic swine model NPT appeared to modulate the intestinal microenvironment, facilitating an early robust, yet transient, host defense mediated by M1 and M2 macrophages. NPT may help overcome immunoparalysis that occurs during inflammatory response to septic injury.

Pretreatment with magnesium ameliorates lipopolysaccharide-induced liver injury in mice

BACKGROUND

Lipopolysaccharide (LPS), a component of the outer membrane of Gram-negative bacteria, is involved in the pathogenesis of sepsis. LPS administration induces systemic inflammation that mimics many of the initial clinical features of sepsis and has deleterious effects on several organs including the liver and eventually leading to septic shock and death. The present study aimed to investigate the protective effect of magnesium (Mg), a well known cofactor in many enzymatic reactions and a critical component of the antioxidant system, on hepatic damage associated with LPS-induced endotoxima in mice.

METHODS

Mg (20 and 40mg/kg, po) was administered for 7 consecutive days. Systemic inflammation was induced 1h after the last dose of Mg by a single dose of LPS (2mg/kg, ip) and 3h thereafter plasma was separated, animals were sacrificed and their livers were isolated.

RESULTS

LPS-treated mice suffered from hepatic dysfunction revealed by histological observation, elevation in plasma transaminases activities, C-reactive protein content and caspase-3, a critical marker of apoptosis. Liver inflammation was evident by elevation in liver cytokines contents (TNF-α and IL-10) and MPO activity. Additionally, oxidative stress was manifested by increased liver lipoperoxidation, glutathione depletion, elevated total nitrate/nitrite (NOx) content and glutathione peroxidase (GPx) activity. Pretreatment with Mg largely mitigated these alternations.

CONCLUSION

Pretreatment with Mg protects the liver from the acute injury which occurs shortly after septicemia.

Removal of inflammatory ascites is associated with dynamic modification of local and systemic inflammation along with prevention of acute lung injury: in vivo and in silico studies

BACKGROUND

Sepsis-induced inflammation in the gut/peritoneal compartment occurs early in sepsis and can lead to acute lung injury (ALI). We have suggested that inflammatory ascites drives the pathogenesis of ALI and that removal of ascites with an abdominal wound vacuum prevents ALI. We hypothesized that the time- and compartment-dependent changes in inflammation that determine this process can be discerned using principal component analysis (PCA) and Dynamic Bayesian Network (DBN) inference.

METHODS

To test this hypothesis, data from a previous study were analyzed using PCA and DBN. In that study, two groups of anesthetized, ventilated pigs were subjected to experimental sepsis via intestinal ischemia/reperfusion and placement of a peritoneal fecal clot. The control group (n = 6) had the abdomen opened at 12 h after injury (T12) with attachment of a passive drain. The peritoneal suction treatment (PST) group (n = 6) was treated in an identical fashion except that a vacuum was applied to the peritoneal cavity at T12 to remove ascites and maintained until T48. Multiple inflammatory mediators were measured in ascites and plasma and related to lung function (PaO2/FIO2 ratio and oxygen index) using PCA and DBN.

RESULTS

Peritoneal suction treatment prevented ALI based on lung histopathology, whereas control animals developed ALI. Principal component analysis revealed that local to the insult (i.e., ascites), primary proinflammatory cytokines play a decreased role in the overall response in the treatment group as compared with control. In both groups, multiple, nested positive feedback loops were inferred from DBN, which included interrelated roles for bacterial endotoxin, interleukin 6, transforming growth factor β1, C-reactive protein, PaO2/FIO2 ratio, and oxygen index. von Willebrand factor was an output in control, but not PST, ascites.

CONCLUSIONS

These combined in vivo and in silico studies suggest that in this clinically realistic paradigm of sepsis, endotoxin drives the inflammatory response in the ascites, interplaying with lung dysfunction in a feed-forward loop that exacerbates inflammation and leads to endothelial dysfunction, systemic spillover, and ALI; PST partially modifies this process.

Pogostone suppresses proinflammatory mediator production and protects against endotoxic shock in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Pogostemon cablin (Blanco) Benth is a well-known medicinal herb commonly used in many Asian countries for inflammatory diseases. Pogostone (PO), a natural product isolated from Pogostemon cablin, is known to exert various pharmacological activities. This study aimed to investigate the anti-inflammatory property of PO, to elucidate its mechanism of action, and to evaluate its potential acute toxicity.

MATERIALS AND METHODS

The in vitro anti-inflammatory activity of PO was assessed using lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. The protein and mRNA levels of proinflammatory mediators were measured with ELISA and RT-PCR, respectively. Proteins of the NF-κB and MAPK family were determined by Western blot to investigate the underlying molecular mechanisms. The in vivo anti-inflammatory activity of PO was tested using LPS-induced endotoxic shock in mice. In addition, the median lethal dose (LD50) of PO in mice was tested in an acute toxicity test.

RESULTS

In vitro, PO significantly inhibited the protein and mRNA expression of proinflammatory mediators including TNF-α, IL-6, IL-1β, NO, and PGE2. The action mechanism of the anti-inflammatory activity of PO was partly dependent on inhibition of the activation of NF-κB and the phosphorylation of JNK and p38 MAPK. In vivo, PO was able to significantly reduce the mortality induced by LPS in mice. Furthermore, PO could markedly suppress the production of the proinflammatory mediators in serum, and attenuate liver and lung injury. The action mechanisms of PO during endotoxic shock may be attributed to down-regulation of the mRNA expression of inflammatory mediators in multiple organs via inhibition of the activation of NF-κB and the phosphorylation of p38 MAPK. Moreover, the LD50 of PO in mice was about 163mg/kg with intravenous administration, which was about 8-fold higher than the dose used in the animal experiment.

CONCLUSIONS

Our findings regarding the anti-inflammatory effect of PO and the underlying molecular mechanisms help justify the use of Pogostemon cablin in Chinese medicine for the treatment of inflammatory diseases. More importantly, the results also render PO a promising anti-inflammatory agent worthy of further development into a pharmaceutical drug for the treatment of septic shock.

Effects of different blood purification methods on serum cytokine levels and prognosis in patients with acute severe organophosphorus pesticide poisoning

The aim of the present study was to investigate the impact of three different blood purification methods, hemoperfusion (HP), continuous blood purification (CBP), and on-line high-volume hemodiafiltration (OL-HDF), on the survival rate of patients with acute severe organophosphorus pesticide poisoning (ASOPP), as well as on major pro-inflammatory (interleukin [IL]-1, IL-6, tumor necrosis factor-α [TNF-α]) and anti-inflammatory (IL-10) cytokines in the serum. Eighty-one ASOPP patients were randomly divided into three groups: HP (N = 23), HP + CBP (N = 26), HP + OL-HD (N = 32). Serum IL-1, IL-6, TNF-α, and IL-10 levels were assessed by ELISA before treatment and at 24 and 48 h post-treatment and survival rates were determined. Patient survival rate was significantly higher in OL-HDF and CBP treated patients compared with HP group (P < 0.05). A significantly greater clearance effect in serum IL-1, IL-6, and TNF-α levels at 24 and 48 h post-treatment was observed in CBP and OL-HDF groups compared with the HP group (P < 0.05). The levels of serum anti-inflammatory cytokine IL-10 increased significantly in CBP and OL-HDF groups compared with the HP group (P < 0.05 at 48 h post-treatment). In addition, OL-HDF treatment achieved similar changes in serum TNF-α, IL-1, IL-6 and IL-10 levels as CBP (P > 0.05). Compared with the HP method, CBP or OL-HDF combined with HP can rapidly clear inflammatory cytokines, reduce systemic inflammatory response syndrome, and improve the survival of ASOPP patients. Compared with CBP, OL-HDF is an economical and effective method to treat ASOPP with less technical difficulty and more suitability for rural areas and primary hospitals.

Clinical study of critical patients with hemorrhagic fever with renal syndrome complicated by acute respiratory distress syndrome

Objectives

The aim of this study was to investigate the clinical characteristics and outcomes of critical patients with hemorrhagic fever with renal syndrome (HFRS) complicated by acute respiratory distress syndrome (ARDS).

Materials and Methods

To observe the demographic, epidemiological and clinical characteristics, and to explore the predictive effects for prognosis in laboratory findings, we conducted a detailed retrospective analysis of clinical records for critical patients with HFRS complicated by ARDS, treated at the center for infectious diseases, Tangdu Hospital, between January 2008 and December 2012.

Results

A total of 48 critical patients with laboratory confirmed HFRS accompanied by ARDS were enrolled in the study, including 27 survivors and 21 non-survivors, with a fatality rate of 43.75%. Thirty-one individuals (64.6%) contracted HFRS between the months of September and December. The non-survivors tended to have lower incidence of overlapping phase (P = 0.025). There were no obvious differences in the needs for mechanical ventilation (MV) and renal replacement therapy (RRT), except for the need for vasoactive drugs between the survivors and non-survivors (P = 0.001). The non-survivors were found to have higher frequencies of encephalopathy, refractory shock and multiple organ dysfunction syndrome (MODS), lower incidences of acute renal failure (ARF) and secondary hypertension (P<0.05). The non-survivors tended to have lower levels of serum creatinine (Scr) (P<0.001) and fibrinogen (Fib) (P = 0.003), higher incidences of prolonged prothrombin time (PT) (P = 0.006) and activated partial thromboplastin time (APTT) (P = 0.020) and higher levels of aspartate aminotransferase (AST) (P = 0.015), and the laboratory parameters mentioned above reached statistical significance for predicting prognosis (P<0.05).

Conclusion

The high mortality rate of critical patients with HFRS complicated by ARDS emphasizes the importance of clinicians’ alertness and timely initiation of systemic supportive therapy.

Nitric oxide transport in blood: a third gas in the respiratory cycle

The trapping, processing, and delivery of nitric oxide (NO) bioactivity by red blood cells (RBCs) have emerged as a conserved mechanism through which regional blood flow is linked to biochemical cues of perfusion sufficiency. We present here an expanded paradigm for the human respiratory cycle based on the coordinated transport of three gases: NO, O₂, and CO₂. By linking O₂ and NO flux, RBCs couple vessel caliber (and thus blood flow) to O₂ availability in the lung and to O₂ need in the periphery. The elements required for regulated O₂-based signal transduction via controlled NO processing within RBCs are presented herein, including S-nitrosothiol (SNO) synthesis by hemoglobin and O₂-regulated delivery of NO bioactivity (capture, activation, and delivery of NO groups at sites remote from NO synthesis by NO synthase). The role of NO transport in the respiratory cycle at molecular, microcirculatory, and system levels is reviewed. We elucidate the mechanism through which regulated NO transport in blood supports O₂ homeostasis, not only through adaptive regulation of regional systemic blood flow but also by optimizing ventilation-perfusion matching in the lung. Furthermore, we discuss the role of NO transport in the central control of breathing and in baroreceptor control of blood pressure, which subserve O₂ supply to tissue. Additionally, malfunctions of this transport and signaling system that are implicated in a wide array of human pathophysiologies are described. Understanding the (dys)function of NO processing in blood is a prerequisite for the development of novel therapies that target the vasoactive capacities of RBCs.

Protective effect of phosphatidylcholine on lipopolysaccharide-induced acute inflammation in multiple organ injury

Soybean polyunsaturated phosphatidylcholine (PC) is thought to exert anti-inflammatory activities and has potent effects in attenuating acute renal failure and liver dysfunction. The aim of this study was to investigate the effects of PC in protecting multiple organ injury (MOI) from lipopolysaccharide (LPS). Six groups of rats (N=8) were used in this study. Three groups acted as controls and received only saline, hydrocortisone (HC, 6 mg/kg, i.v.) or PC (600 mg/kg, i.p.) without LPS (15 mg/kg, i.p.) injections. Other 3 groups, as the test groups, were administered saline, HC or PC in the presence of LPS. Six hours after the LPS injection, blood and organs (lung, liver and kidney) were collected from each group to measure inflammatory cytokines and perform histopathology and myeloperoxidase (MPO) assessment. Serum cytokines (TNF-α, IL-6 and IL-10) and MPO activities were significantly increased, and significant histopathological changes in the organs were observed by LPS challenge. These findings were significantly attenuated by PC or HC. The treatment with PC or HC resulted in a significant attenuation on the increase in serum levels of TNF-α and IL-6, pro-inflammatory cytokines, while neither PC nor HC significantly attenuated serum levels of IL-10, anti-inflammatory cytokine. In the organs, the enhanced infiltration of neutrophils and expression of ED2 positive macrophage were attenuated by PC or HC. Inductions of MPO activity were also significantly attenuated by PC or HC. From the findings, we suggest that PC may be a functional material for its use as an anti-inflammatory agent.

Predictors of 30-day mortality and outcome in cases of myocardial infarction with cardiogenic shock treated by extracorporeal life support

OBJECTIVES

The twin aims of this study were to identify the independent predictors of 30-day mortality and to analyse the outcomes of patients with cardiogenic shock (CS) associated with acute myocardial infarction (AMI) and necessitating extracorporeal life support (ECLS).

METHODS

The investigation was a single-centre, retrospective study of 77 patients who required ECLS for AMI with CS. A logistic regression analysis was performed to identify the independent variables associated with 30-day mortality.

RESULTS

Between February 2006 and November 2009, 745 patients in our establishment received ECLS. In the single-centre cohort, we retrospectively reviewed 77 patients who had required ECLS support for AMI with CS. The delay between AMI and CS ECLS was 15 ± 4 h. PCI was performed in 58 patients (75.3%) and isolated emergency CABG in 12 (15.6%). The remaining 7 patients (9.1%) did not undergo revascularization. ECLS duration averaged 9.8 ± 7.1 days. Nineteen patients were successfully weaned from ECLS (24%). Fifty-eight patients did not undergo or did not tolerate the weaning trial (76%). Forty patients died during ECLS support, 13 were implanted with a mono-ventricular (n = 9) or biventricular assist device (n = 4) and 5 were bridged to heart transplantation. Complications consisted primarily in pneumonia (51.3%) and acute renal failure requiring haemofiltration (46.1%). Pulmonary oedema occurred in 24 patients (31.6%) and major bleeding in 16 (21.33%). 30-day and in-hospital survival rates were, respectively, 38.9 and 33.8%. Multivariable analysis identified preimplantation lactate serum level, preimplantation creatinine serum level and previous cardiopulmonary resuscitation as independent predictors of 30-day mortality.

CONCLUSIONS

Prompt ECLS support is an effective strategy and provides a reasonable chance of survival in patients with AMI associated with profound CS. As shown in our results pertaining to predictive risk factors for 30-day mortality, reducing the duration of end-organ ischaemia is the keystone to management of this patient population. A major remaining challenge will consist in preventing pulmonary oedema following peripheral ECLS.

Sodium aescinate ameliorates liver injury induced by methyl parathion in rats

Methyl parathion, a highly cytotoxic insecticide, has been used in agricultural pest control for several years. The present study investigated the protective effect of sodium aescinate (SA, the sodium salt of aescin) against liver injury induced by methyl parathion. Forty male Sprague-Dawley rats were randomly divided into 5 groups of 8 animals: the control group; the methyl parathion (15 mg/kg) poisoning (MP) group; and the MP plus SA at doses of 0.45, 0.9 and 1.8 mg/kg groups. Alanine aminotransferase (ALT), aspartate aminotransferase (AST) and acetylcholinesterase (AChE) in the plasma were assayed. Nitric oxide (NO) and antioxidative parameters were measured. Histopathological examination of the liver was also performed. The results revealed that SA had no effect on AChE. Treatment with SA decreased the activities of ALT and AST, and the levels of malondialdehyde and NO. Treatment with SA also increased the level of glutathione and the activities of superoxide dismutase and glutathione peroxidase. SA administration also ameliorated liver injury induced by methyl parathion poisoning. The findings indicate that SA protects against liver injury induced by methyl parathion and that the mechanism of action is related to the antioxidative and anti-inflammatory effects of SA.

Protective effect of aescin from the seeds of Aesculus hippocastanum on liver injury induced by endotoxin in mice

To investigate the effect and underlying mechanism of aescin on acute liver injury induced by endotoxin, liver injury was established by injecting lipopolysaccharide (LPS) in mice. Animals were assigned to seven groups: the control group and groups treated with LPS (40 mg/kg), aescin (3.6 mg/kg), LPS plus dexamethasone (4 mg/kg) and LPS plus aescin (0.9, 1.8 or 3.6 mg/kg). Hepatic histopathological changes were examined under a light microscope. Activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum were determined. Levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), nitric oxide (NO) and antioxidative parameters in liver homogenate were measured. Glucocorticoid receptor (GR), 11 beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1) and 11 beta-hydroxysteroid dehydrogenase type 2 (11β-HSD2) expressions in liver were determined by western blotting. Treatment with escin could inhibit immigration of inflammatory cells, alleviate the degree of necrosis, and decrease serum ALT and AST activities. Aescin also down-regulated levels of inflammation mediators (TNF-α, IL-1β and NO) and 11β-HSD2 expression in liver, up-regulated GR expression, enhanced endogenous antioxidative capacity, but have no obvious effect on 11β-HSD1 expression in liver. The findings suggest aescin has protective effects on endotoxin-induced liver injury, and the underlying mechanisms were associated with its anti-inflammatory effects, up-regulating GR expression, down-regulating 11β-HSD2 experssion, and antixoidation.

Peritoneal negative pressure therapy prevents multiple organ injury in a chronic porcine sepsis and ischemia/reperfusion model

Sepsis and hemorrhage can result in injury to multiple organs and is associated with an extremely high rate of mortality. We hypothesized that peritoneal negative pressure therapy (NPT) would reduce systemic inflammation and organ damage. Pigs (n = 12) were anesthetized and surgically instrumented for hemodynamic monitoring. Through a laparotomy, the superior mesenteric artery was clamped for 30 min. Feces was mixed with blood to form a fecal clot that was placed into the peritoneum, and the abdomen was closed. All subjects were treated with standard isotonic fluid resuscitation, wide spectrum antibiotics, and mechanical ventilation, and were monitored for 48 h. Animals were separated into two groups 12 h (T12) after injury: for NPT (n = 6), an abdominal wound vacuum dressing was placed in the laparotomy, and negative pressure (-125 mmHg) was applied (T12 - T48), whereas passive drainage (n = 6) was identical to the NPT group except the abdomen was allowed to passively drain. Negative pressure therapy removed a significantly greater volume of ascites (860 ± 134 mL) than did passive drainage (88 ± 56 mL). Systemic inflammation (e.g. TNF-α, IL-1β, IL-6) was significantly reduced in the NPT group and was associated with significant improvement in intestine, lung, kidney, and liver histopathology. Our data suggest NPT efficacy is partially due to an attenuation of peritoneal inflammation by the removal of ascites. However, the exact mechanism needs further elucidation. The clinical implication of this study is that sepsis/trauma can result in an inflammatory ascites that may perpetuate organ injury; removal of the ascites can break the cycle and reduce organ damage.

Plasma proteome response to severe burn injury revealed by 18O-labeled "universal" reference-based quantitative proteomics

A burn injury represents one of the most severe forms of human trauma and is responsible for significant mortality worldwide. Here, we present the first quantitative proteomics investigation of the blood plasma proteome response to severe burn injury by comparing the plasma protein concentrations of 10 healthy control subjects with those of 15 severe burn patients at two time-points following the injury. The overall analytical strategy for this work integrated immunoaffinity depletion of the 12 most abundant plasma proteins with cysteinyl-peptide enrichment-based fractionation prior to LC-MS analyses of individual patient samples. Incorporation of an 18O-labeled "universal" reference among the sample sets enabled precise relative quantification across samples. In total, 313 plasma proteins confidently identified with two or more unique peptides were quantified. Following statistical analysis, 110 proteins exhibited significant abundance changes in response to the burn injury. The observed changes in protein concentrations suggest significant inflammatory and hypermetabolic response to the injury, which is supported by the fact that many of the identified proteins are associated with acute phase response signaling, the complement system, and coagulation system pathways. The regulation of approximately 35 proteins observed in this study is in agreement with previous results reported for inflammatory or burn response, but approximately 50 potentially novel proteins previously not known to be associated with burn response or inflammation are also found. Elucidating proteins involved in the response to severe burn injury may reveal novel targets for therapeutic interventions as well as potential predictive biomarkers for patient outcomes such as multiple organ failure.

Towards a unifying, systems biology understanding of large-scale cellular death and destruction caused by poorly liganded iron: Parkinson's, Huntington's, Alzheimer's, prions, bactericides, chemical toxicology and others as examples

Exposure to a variety of toxins and/or infectious agents leads to disease, degeneration and death, often characterised by circumstances in which cells or tissues do not merely die and cease to function but may be more or less entirely obliterated. It is then legitimate to ask the question as to whether, despite the many kinds of agent involved, there may be at least some unifying mechanisms of such cell death and destruction. I summarise the evidence that in a great many cases, one underlying mechanism, providing major stresses of this type, entails continuing and autocatalytic production (based on positive feedback mechanisms) of hydroxyl radicals via Fenton chemistry involving poorly liganded iron, leading to cell death via apoptosis (probably including via pathways induced by changes in the NF-κB system). While every pathway is in some sense connected to every other one, I highlight the literature evidence suggesting that the degenerative effects of many diseases and toxicological insults converge on iron dysregulation. This highlights specifically the role of iron metabolism, and the detailed speciation of iron, in chemical and other toxicology, and has significant implications for the use of iron chelating substances (probably in partnership with appropriate anti-oxidants) as nutritional or therapeutic agents in inhibiting both the progression of these mainly degenerative diseases and the sequelae of both chronic and acute toxin exposure. The complexity of biochemical networks, especially those involving autocatalytic behaviour and positive feedbacks, means that multiple interventions (e.g. of iron chelators plus antioxidants) are likely to prove most effective. A variety of systems biology approaches, that I summarise, can predict both the mechanisms involved in these cell death pathways and the optimal sites of action for nutritional or pharmacological interventions.

Open surgical repair of ruptured juxtarenal aortic aneurysms with and without renal cooling: observations regarding morbidity and mortality

OBJECTIVES

Little is known about the outcome of ruptured juxtarenal aortic aneurysm (RJAA) repair. Surgical treatment of RJAAs requires suprarenal aortic cross-clamping, which causes additional renal ischemia-reperfusion injury on top of the pre-existing hypovolemic shock syndrome. As endovascular alternatives rarely exist in this situation, open repair continues to be the gold standard. We analyzed our results of open RJAA repair during an 11-year period.

DESIGN

Retrospective observational study.

MATERIALS AND METHODS

Between July 1997 and December 2008, all consecutive patients with RJAAs were included in the study. Part of these patients received cold perfusion of the kidneys during suprarenal aortic cross-clamping. Perioperative variables, morbidity, and 30-day or in-hospital mortality were assessed. Renal insufficiency was defined as an acute rise of >or=0.5 mg/dL in serum creatinine level. Multiple organ failure (MOF) was scored using the sequential organ failure assessment score (SOFA score).

RESULTS

A total of 29 consecutive patients with an RJAA, confirmed by computed tomography-scanning, presented to our hospital. In eight patients, the operation was aborted before the start of aortic repair, because no blood pressure could be regained in spite of maximal resuscitation measures. They were excluded from further analysis. Of the remaining 21 patients, 10 died during hospital stay. Renal insufficiency occurred in 11 out of 21 of the patients. Eleven out of 21 patients developed MOF postoperatively. In a subgroup of patients who received renal cooling during suprarenal aortic clamping, the 30-day or in-hospital mortality was two of 10 vs eight of 11 in patients who did not receive renal cooling (P = .03); renal insufficiency occurred in one out of 10 patients in the subgroup with renal cooling vs 10 out of 11 without renal cooling (P < .001) and MOF in two of 10 vs nine of 11, respectively (P = .009).

CONCLUSIONS

Open surgical repair of RJAAs is still associated with high mortality and morbidity. To our knowledge, this is the first report of cold perfusion of the kidneys during RJAA repair. Although numbers are small, a beneficial effect of renal cooling on the outcome of RJAA repair is suggested, warranting further research with this technique.

Culture conditions and treatments affect Caco-2 characteristics and particle uptake

Small intestinal microparticle uptake via a paracellular route is relevant to oral drug delivery and environmental pollution. In vitro investigation uses latex microparticle passage across a confluent Caco-2 cell epithelium. This paper examines the influence of culture conditions on transepithelial resistance (TER); cell dimensions from confocal microscopy; and number of particles below the epithelium. Variables investigated include level of initial TER; multiple TER measurements; involvement of medium; cell source; and pretreatment with ethanol or a range of temperatures. Data were collected after exposure to 2 microm latex particles for 5-120 min: sham groups were exposed to pretreatment but not particles. The results highlight the importance of very precise control of the experimental environment; confirm the pattern of sequential-TER increase/decrease in groups exposed only to particles and show accompanying increases in cell dimensions. Greater particle uptake was associated with ethanol-induced decreased TER, decreased cell height and increased intercellular spaces, similar to previous findings for external irradiation. Low temperatures raised TER but, despite this, cooling did not alter particle uptake. In conclusion, culture microenvironment and sham treatment are crucial considerations in studies of epithelial microparticle uptake in vitro.

Heart-type fatty acid-binding protein is a useful marker for organ dysfunction and leptin alleviates sepsis-induced organ injuries by restraining its tissue levels

Heart-type fatty acid-binding protein (H-FABP) is widely distributed and has been used to diagnose certain diseases. However, its alteration during infection-evoked organ dysfunction, and the potential association between leptin and it in injury or infection has not been investigated. In the current study, serum H-FABP, leptin, C-reactive protein and interleukin-1beta in the patients with pulmonary infection-induced multiple organ dysfunction were detected. Moreover, a mouse model of sepsis was established, and serum alanine transaminase, uric acid, tissue H-FABP, myeloperoxidase, superoxide dismutase activity and histological alterations in lung and intestine were investigated. Serum H-FABP and leptin increased simultaneously and significantly in the patients, and leptin alleviated pulmonary and intestinal injuries by restraining tissue H-FABP secretions in the mouse model of sepsis. Other investigated variables showed different but independent alterations. In conclusion, H-FABP represents a useful diagnostic marker for organ dysfunction, and its association with leptin will be a novel target for emergency aid.

[Coupled plasma filtration adsorption: rationale and perspectives in septic shock]

PURPOSE

Septic shock is the leading cause of multiple organ failure and mortality in intensive care units. This condition seems to be related to an overproduction of both pro- and anti-inflammatory mediators, leading to an immunological dysfunction. Therapeutic strategies aimed at reducing blood and tissue concentrations of these mediators have been developed. One of these techniques, based on extra-renal filtration, is called "coupled plasma filtration and adsorption".

SOURCE

English and French language articles published between 1984 and 2008 were identified through a computerized Medline search. Keywords and MeSH terms used were: "coupled plasmafiltration", "coupled plasma filtration", "adsorption", "blood purification", "cytokines", "hemofiltration", "sepsis". Relevant publications were retrieved and scanned for additional sources. Nine publications were found.

PRINCIPAL FINDINGS

Coupled plasma filtration adsorption is an extra-corporeal treatment, based on non-specific cytokine adsorption on a specially designed resin cartridge, coupled with hemofiltration. Experimental studies and the first clinical trials have shown interesting results regarding hemodynamics and respiratory parameters. However, these trials failed to demonstrate any improvement in outcome.

CONCLUSION

Additional evidence is needed to clarify the role of this blood purification technique for the treatment of septic shock.

Iron behaving badly: inappropriate iron chelation as a major contributor to the aetiology of vascular and other progressive inflammatory and degenerative diseases

BACKGROUND

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular 'reactive oxygen species' (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation.

REVIEW

We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation).The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible.This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, since in some circumstances (especially the presence of poorly liganded iron) molecules that are nominally antioxidants can actually act as pro-oxidants. The reduction of redox stress thus requires suitable levels of both antioxidants and effective iron chelators. Some polyphenolic antioxidants may serve both roles.Understanding the exact speciation and liganding of iron in all its states is thus crucial to separating its various pro- and anti-inflammatory activities. Redox stress, innate immunity and pro- (and some anti-)inflammatory cytokines are linked in particular via signalling pathways involving NF-kappaB and p38, with the oxidative roles of iron here seemingly involved upstream of the IkappaB kinase (IKK) reaction. In a number of cases it is possible to identify mechanisms by which ROSs and poorly liganded iron act synergistically and autocatalytically, leading to 'runaway' reactions that are hard to control unless one tackles multiple sites of action simultaneously. Some molecules such as statins and erythropoietin, not traditionally associated with anti-inflammatory activity, do indeed have 'pleiotropic' anti-inflammatory effects that may be of benefit here.

CONCLUSION

Overall we argue, by synthesising a widely dispersed literature, that the role of poorly liganded iron has been rather underappreciated in the past, and that in combination with peroxide and superoxide its activity underpins the behaviour of a great many physiological processes that degrade over time. Understanding these requires an integrative, systems-level approach that may lead to novel therapeutic targets.

Changes produced by external radiation in parameters influencing intestinal permeability and microparticle uptake in vitro

PURPOSE

To determine the interaction between X-irradiation and in vitro intestinal microparticle uptake through Caco-2 epithelial cells.

METHODS

Caco-2 cells were cultured on 3 microm porous membranes for 21 days, X-irradiated with 2 Gy or sham-irradiated, then incubated for 5 or 30 min and exposed apically for 30 min to 2 microm latex microparticles. Measurements included cell dimensions, from confocal microscope 'optical slices'; transepithelial resistance (TER) for tight junction (TJ) permeability; particle aggregation; and particle numbers on (adsorbed), in (intraepithelial) and through (submembranous) the epithelium.

RESULTS

Irradiation alone reduced TJ permeability more than sham-treatment, more so 5 min than 30 min after treatment. Irradiated epithelia were more permeable to particles than the equivalent sham-irradiated or previously untreated (particle only) groups: the latter two were similar. Irradiation altered adsorbed particle numbers and increased submembranous counts: particle uptake correlated best with cell height.

CONCLUSIONS

2 Gy X-irradiation increased particle uptake and translocation through the epithelium. This correlated well with the TJ opening seen after particle exposure in irradiated samples and changes in cell morphology. New data on cell dimensions underlined the similarity in particle uptake between this in vitro epithelium and that in an in vivo model, highlighting the translational significance of the work.

Minus charge stimulation prevents LPS-induced liver injury by reduction of nitric oxide

The liver is one of the major target organs affected in sepsis that are usually accompanied with free radical formation. The use of minus charge for the prevention and cure of various radical related diseases is gaining wide importance in the medicinal field. Here, we investigate whether minus charge stimulation (MCS) inhibits nitric oxide (NO) production induced by lipopolysaccharide (LPS) in the mice liver. The survival rate was compared in LPS-treated group with MCS group. The liver NO radical was measured using electron spin resonance technique. Serum alanine transaminase (ALT) was estimated for liver injury. MCS significantly improved the survival rate of LPS-treated mice and inhibited increase of ALT in serum levels. MCS also reduced NO radical production significantly in the LPS-treated mice liver tissue. In conclusion, our results indicate that MCS prevents LPS-induced liver injury, which may be through the inhibition of liver NO radical production.

SPG/IND-induced septic shock in a LPS-low responder strain, C3H/HeJ mice

The administration of beta-glucan (sonifilan; SPG) in combination with a non-steroidal anti-inflammatory drug, indomethacin (IND), induced lethal septic shock in mice. To demonstrate the influence of bacterial lipopolysaccharide (LPS) in this lethal toxicity, LPS non-responder C3H/HeJ mice were used to compare features of sepsis and physicochemical parameters in the present study. The administration of SPG and IND induced the death of C3H/HeJ mice, lowering rectal temperature, reducing body weight, increasing serum tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) levels, shortening the gastrointestinal tract, and increasing the GOT/GPT level. Microbial translocation to various organs was also significantly increased. These results strongly suggested that LPS-non-responding strain also induced septic shock in this experimental model, and other pathogen-associated molecular patterns (PAMPs) may significantly contribute to the septic shock.

Factors influencing intestinal microparticle uptake in vivo

The aim of this study is to compare microparticle uptake in animals of different ages, gender and species and at different time points. The 2mum latex/in vivo in situ model uses the observation of animal responses or post-mortem changes and also particle identification by fluorescence microscopy in nine sequential intestinal segments and secondary sites. The wide size range of animals studied requires particle numbers in tissue compartments to be related to intestinal tissue section area through a circumference measurement. Area under the curve (AUC) data for particles in intestinal tissue are plotted against measurements of intestinal length, allowing comparisons to be made across different ages and species and between males and females. The percentage uptake of administered dose and particle numbers in macerated tissue are also reported. Some parameters, in particular species, do not appear to affect the extent of microparticle uptake, which ranges from 0.12 to 0.32% of the administered dose. Particle uptake does, however, vary with age, being significantly greater in young adult males (7 weeks) than in younger (3 weeks) and older (17 and 52 weeks) age groups. It is concluded that age is more important in determining the extent of uptake than gender or species.

Anti-inflammatory Strategies and Hemostatic Agents: Old Drugs, New Ideas

Hemostatic abnormalities occur following injury associated with both cardiac and noncardiac surgery. These changes are part of inflammatory pathways with signaling mechanisms that link these diverse pathways. The inflammatory response to surgery is exacerbated by allogeneic blood transfusion by enhancing intrinsic inflammatory activity and directly increasing plasma levels of inflammatory mediators. Surgical patients can be preventively treated with pharmacologic agents to modulate inflammatory responses. Multiple studies have reported preventive pharmacologic therapies to reduce bleeding and the need for allogeneic transfusions in surgery. Strategies for cardiac surgical patients during cardiopulmonary bypass include administration of either lysine analogs, such as epsilon aminocaproic acid and tranexamic acid, or the serine protease inhibitor aprotinin.

Alterations of trace elements (Zn, Se, Cu, Fe) and related metalloenzymes in rabbit blood after severe trauma

To investigate the status of the trace elements (TEs) and related metalloenzymes activities in the injury and repair process after severe trauma, we established a rabbit model of severe trauma whose Injury Severity Score (ISS) was 22. Concentrations of blood selenium (Se) and serum copper (Cu), zinc (Zn), iron (Fe), and ferritin were measured on D0 (before injury), and day (D) 1, D2, D3, D6, D9, D14, D21, D28 after trauma, respectively. The activities of glutathione peroxidase (GPx), Cu/Zn superoxide dismutase (Cu/Zn-SOD), myeloperoxidase (MPO), the contents of lipid peroxidation product malondialdehyde (MDA) and serum biochemical profile were detected synchronously. In addition, the morphologic changes of major organs were observed at different time intervals. Results showed that blood Se and serum Zn, Fe contents decreased significantly within 2 weeks after injury. Serum Cu concentration was significantly reduced on D1 but normalized quickly. Serum ferritin level increased during the first week while following an obvious decrease thereafter. The blood GPx activity dropped markedly from D1 to D6, the serum Cu/Zn-SOD activity decreased on D1 and then increased significantly within 2 weeks, and the blood MPO-positive stained cells increased within a week after trauma and followed by a decrease from D14 to D21. The serum MDA increased significantly on D6. Seven of 34 rabbits died in 4-6 days after injury. Biochemistry values and pathological features revealed these rabbits died of multiple organ dysfunction syndrome (MODS). Our experiment suggested that the circulating TEs status is dramatically modified in response to trauma, which might be a factor in MODS.

The lower intestinal tract-specific induction of heme oxygenase-1 by glutamine protects against endotoxemic intestinal injury

OBJECTIVE

The aim of the present study was to investigate whether glutamine pretreatment improves intestinal injury in rats with endotoxemia by its heme oxygenase-1 induction in the lower intestinal tract.

DESIGN

Randomized, blinded, controlled animal study.

SETTING

University-based animal research facility.

SUBJECTS

Sprague-Dawley male rats, weighing 220-250 g (n = 201).

INTERVENTIONS

Rats were treated with glutamine (0.75 g/kg) dissolved in lactated Ringer's solution via the tail vein. Endotoxemia was induced in rats by intraperitoneal injection of lipopolysaccharide (10 mg/kg or 20 mg/kg for survival study). Lipopolysaccharide-treated animals were pretreated with glutamine or lactated Ringer's solution 9 hrs before lipopolysaccharide treatment. Some of the glutamine-pretreated animals further received tin mesoporphyrin (1 micromol/kg), a specific inhibitor of heme oxygenase activity, 1 hr before lipopolysaccharide treatment.

MEASUREMENTS AND MAIN RESULTS

Glutamine treatment markedly induced heme oxygenase-1 messenger RNA and protein in the mucosal epithelial cells as well as in the lamina propria cells in the ileum and the colon, whereas its expression in the duodenum and the jejunum was not influenced by the treatment. Glutamine treatment before lipopolysaccharide administration significantly ameliorated lipopolysaccharide-induced mucosal injury, inflammation, and apoptotic cell death in the ileum and the colon, as judged by significant decreases in tumor necrosis factor-alpha gene expression, histologic damage scores, and expression of activated caspase-3 and by an increase in gene expression of Bcl-2. In addition, glutamine treatment markedly decreased lipopolysaccharide-induced mortality. In contrast, treatment with tin mesoporphyrin abolished the beneficial effect of glutamine pretreatment.

CONCLUSIONS

Glutamine pretreatment significantly ameliorated intestinal tissue injury of rats following lipopolysaccharide treatment. The same treatment also improved the survival of animals from endotoxemia. The protective effect of glutamine is mediated by its lower intestine-specific induction of heme oxygenase-1, since its inhibition by tin mesoporphyrin completely abolished the beneficial effect of glutamine.