Understanding the heart-brain axis response in COVID-19 patients: A suggestive perspective for therapeutic development.

In-depth characterization of heart-brain communication in critically ill patients with severe acute respiratory failure is attracting significant interest in the COronaVIrus Disease 19 (COVID-19) pandemic era during intensive care unit (ICU) stay and after ICU or hospital discharge. Emerging research has provided new insights into pathogenic role of the deregulation of the heart-brain axis (HBA), a bidirectional flow of information, in leading to severe multiorgan disease syndrome (MODS) in patients with confirmed infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Noteworthy, HBA dysfunction may worsen the outcome of the COVID-19 patients. In this review, we discuss the critical role HBA plays in both promoting and limiting MODS in COVID-19. We also highlight the role of HBA as new target for novel therapeutic strategies in COVID-19 in order to open new translational frontiers of care. This is a translational perspective from the Italian Society of Cardiovascular Researches.

The sepsis induced defective aggravation of immune cells: a translational science underling chemico-biological interactions from altered bioenergetics and/or cellular metabolism to organ dysfunction.

Sepsis is described as a systemic immune response of the body to an infectious process that might result in dysfunctional organs that may lead to death. In clinical practice, sepsis is considered a medical emergency. The initial event in sepsis caused by a deregulated host response towards harmful microorganisms that leads to an aggravated systemic inflammatory response syndrome (SIRS) to tackle with pathogen invasion and a compensatory anti-inflammatory response syndrome (CARS) that lasts for several days. The inflammatory response and the cellular damage as well as the risk of an organ dysfunction are in direct proportion. Even though, the pathogenesis of sepsis remains unclear, many studies have shown evidence of role of oxidants and antioxidants in sepsis. The altered innate and adaptive immune cell and upregulated production and release of cytokines and chemokines most probably due to involvement of JAK-STAT pathway, disturbance in redox homeostasis due to low clearance of lactate and other oxidative stressors, contributes to sepsis process to organ dysfunction which contribute to increase rates of mortality among these patients. Hence, the treatment strategies for sepsis include antibiotics, ventilator and blood glucose management and other strategies for resuscitation are rapidly progressing. In the current review, we mainly concentrate on throwing light on the main molecular aspects and chemico-biological interactions that shows involvement in pathways manipulating alteration in physiology of immune cells (innate and adaptive) that change the bioenergetics/cellular metabolism to organ dysfunction and correlation of these altered pathway, improve the understating for new therapeutic target for sepsis.

Hydrogen alleviated organ injury and dysfunction in sepsis: The role of cross-talk between autophagy and endoplasmic reticulum stress: Experimental research.

AIMS: Sepsis is defined as a life-threatening organ dysfunction that is caused by a dysregulated host response to infection. Although much progress has been made in understanding the pathophysiology of sepsis, further discussion and study of the detailed therapeutic mechanisms are needed. Autophagy and endoplasmic reticulum stress are two pathways of the complicated regulatory network of sepsis. Herein, we focus on the cellular mechanism in which autophagy and endoplasmic reticulum stress participate in hydrogen (H2)-protected sepsis-induced organ injury. MATERIALS AND METHODS: Male C57BL/6 mice were randomly divided into the following groups: control group, cecal ligation puncture (CLP) group, CLP + tunicamycin(TM) group, CLP + 4-phenyl butyric acid (4-PBA) group, CLP + rapamycin (Rap) group, CLP + 3-methyladenine (3-MA) group, CLP + H2 group, CLP + H2 + 3-MA group, and CLP + H2 + TM group. After the experiment was completed, autophagosome was detected by transmission electron microscopy; protein PKR-like ER kinase (PERK), p-PERK, Eukaryotic translation initiation factor-2α (eIF2α), p-eIF2α, inositol-requiring enzyme1α(IRE1α), C/EBP homologous protein(CHOP), activating transcription factor(ATF), XBP-1, microtubule-associated protein 1 light(LC3), Beclin1, PTEN-induced putative kinase 1(PINK1), Parkin, and p65 subunit of Nuclear factor kappa B(NF-κb) were measured by Western blot; myeloperoxidase(MPO) activity in lung, bronchoalveolar lavage(BAL) total protein, lung wet-to-dry(W/D) ratio, serum biochemical indicators, 7-day survival rate, and pathological injury scores of lung, liver, and kidney were tested; and cytokines tumor necrosis factor-α(TNF-α), Interleukin(IL)-1ß, and IL-6 and high mobility group box protein (HMGB)1 were detected by enzyme-linked immunosorbent assay(ELISA). RESULTS: We demonstrated that sepsis induced endoplasmic reticulum stress. Moreover, it was found that an increase in endoplasmic reticulum impaired autophagy activity in sepsis, and the absence of endoplasmic reticulum stress attenuated tissue histological injury and dysfunction of lung, liver, and kidney in septic mice. Intriguingly, hydrogen alleviated the endoplasmic reticulum stress via the autophagy pathway and also mitigated inflammation and organ injury. CONCLUSION: Hydrogen provided protection from organ injury induced by sepsis via autophagy activation and endoplasmic reticulum stress pathway inactivation.

Clinical assessment and management of severe acute pancreatitis: a multi-disciplinary approach in the XXI century.

Acute pancreatitis (AP) is the most common gastrointestinal disorder requiring hospitalization, with a high rate of morbidity and mortality. Severe AP is characterized by the presence of persistent organ failure involving single or multiple organs. Clinical evolution, laboratory and radiological assessment are necessary to evaluate the prognosis and inform the management of AP. The onset of severe AP may be classified in two principal phases. The early phase, during the first week, is characterized by the activation of the auto-inflammatory cascade, gut dysbiosis, bacterial translocation, and the down-regulation of immune responses. The late phase is characterized by the development of local and systemic complications. Several old paradigms have been amended in the management of AP patients, such as the indication of nutrition, the use of antibiotic therapy, pain control strategies, and even the use of surgery. Real world evidence has shown that in the majority of cases a step-up approach is most effective. In this review, we discuss the clinical assessment and improvements to the management of patients with severe AP in a high volume center where a multi-disciplinary approach is performed.

Activated Protein C Attenuates Severe Inflammation by Targeting VLA-3high Neutrophil Subpopulation in Mice.

The host injury involved in multiorgan system failure during severe inflammation is mediated, in part, by massive infiltration and sequestration of hyperactive neutrophils in the visceral organ. A recombinant form of human activated protein C (rhAPC) has shown cytoprotective and anti-inflammatory functions in some clinical and animal studies, but the direct mechanism is not fully understood. Recently, we reported that, during endotoxemia and severe polymicrobial peritonitis, integrin VLA-3 (CD49c/CD29) is specifically upregulated on hyperinflammatory neutrophils and that targeting the VLA-3high neutrophil subpopulation improved survival in mice. In this article, we report that rhAPC binds to human neutrophils via integrin VLA-3 (CD49c/CD29) with a higher affinity compared with other Arg-Gly-Asp binding integrins. Similarly, there is preferential binding of activated protein C (PC) to Gr1highCD11bhighVLA-3high cells isolated from the bone marrow of septic mice. Furthermore, specific binding of rhAPC to human neutrophils via VLA-3 was inhibited by an antagonistic peptide (LXY2). In addition, genetically modified mutant activated PC, with a high affinity for VLA-3, shows significantly improved binding to neutrophils compared with wild-type activated PC and significantly reduced neutrophil infiltration into the lungs of septic mice. These data indicate that variants of activated PC have a stronger affinity for integrin VLA-3, which reveals novel therapeutic possibilities.

Polydatin: a new therapeutic agent against multiorgan dysfunction.

BACKGROUND: Polydatin (PD), a monocrystalline and polyphenolic drug isolated from a traditional Chinese herb (Polygonum cuspidatum), is protective against mitochondrial dysfunction and has been approved for clinical trials in the treatment of shock. However, whether the administration of PD has a therapeutic effect on multiple-organ dysfunction syndrome (MODS) requires investigation. MATERIAL AND METHODS: MODS was induced in Sprague-Dawley rats via hemorrhage and ligation and puncture of cecum-induced sepsis. The rats were divided into three groups as follows: MODS + PD, MODS + normal saline, and a control group (no treatment). Survival time, blood biochemical indexes, and histopathologic changes in various organs were evaluated; serum oxidative stress (advanced oxidative protein products [AOPPs]) and proinflammatory cytokines (tumor necrosis factor-α, interleukin 1ß, and interleukin 6) were assayed using enzyme-linked immunosorbent assay. Apoptosis-related protein expression (B-cell lymphoma-2 [Bcl-2] and Bax) was assayed by immunohistochemical and Western blotting methods, whereas caspase-3 activity was assayed by spectrophotometry. RESULTS: PD improved organ function, prolonged survival time, and reduced MODS incidence and serum levels of AOPPs and proinflammatory cytokines. It also decreased Bax levels and caspase-3 activity and increased Bcl-2 levels in the kidney and liver. CONCLUSIONS: PD may serve as a potential therapeutic for MODS, as it suppresses oxidative stress, inhibits inflammatory response, attenuates apoptosis, and protects against mitochondrial dysfunction.

Veno-occlusive disease of the liver in the absence of elevation in bilirubin in pediatric patients after hematopoietic stem cell transplantation.

Veno-occlusive disease (VOD) of the liver is a well-described and significant complication of hematopoietic stem cell transplantation (HSCT), with limited successful therapeutic options in severe cases. Prompt diagnosis and initiation of treatment is crucial to restrict the extent of disease. However, a subset of patients may not meet all current diagnostic criteria at presentation, and waiting for these to be met may delay therapy. We retrospectively reviewed 794 HSCT patients treated at our institution between 2003 and 2013, identifying 17 (2.1%) who developed VOD. Of these, 5 (29%) were noted to have an absence of elevated bilirubin at the time of VOD diagnosis and reversal of portal venous flow on ultrasound. Median total and conjugated bilirubin at VOD diagnosis were 1.0 and 0.2 mg/dL, respectively. All 5 patients were subsequently diagnosed with multiorgan failure associated with VOD, including 1 with encephalopathy. Four were treated with intravenous high-dose methylprednisolone (500 mg/m(2) per dose every 12 hours for 6 doses). One patient received defibrotide therapy in addition to steroids and another supportive care alone. VOD resolved in 4 of 5 patients, with median time to resolution of VOD, defined as recovery of all organ function and normalization of bilirubin and portal venous flow, of 8 days. Two patients died later from progressive primary disease and chronic graft-versus-host disease, respectively. We conclude that a high index of suspicion for VOD should be maintained in patients despite lack of bilirubin elevation in the presence of other diagnostic criteria such as hepatomegaly, abdominal pain, ascites, or weight gain. Early ultrasound evaluation in these patients may lead to more timely diagnosis and therapeutic interventions.

Cytokine release assays: current practices and future directions.

As a result of the CD28 superagonist biotherapeutic monoclonal antibody (TGN 1412) "cytokine storm" incident, cytokine release assays (CRA) have become hazard identification and prospective risk assessment tools for screening novel biotherapeutics directed against targets having a potential risk for eliciting adverse pro-inflammatory clinical infusion reactions. Different laboratories may have different strategies, assay formats, and approaches to the reporting, interpretation, and use of data for either decision making or risk assessment. Additionally, many independent contract research organizations (CROs), academic and government laboratories are involved in some aspect of CRA work. As a result, while some pharmaceutical companies are providing CRA data as part of the regulatory submissions when necessary, technical and regulatory practices are still evolving to provide data predictive of cytokine release in humans and that are relevant to safety. This manuscript provides an overview of different approaches employed by the pharmaceutical industry and CROs, for the use and application of CRA based upon a survey and post survey follow up conducted by ILSI-Health and Environmental Sciences Institute (HESI) Immunotoxicology Committee CRA Working Group. Also discussed is ongoing research in the academic sector, the regulatory environment, current limitations of the assays, and future directions and recommendations for cytokine release assays.

Acute pancreatitis with organ dysfunction associates with abnormal blood lymphocyte signaling: controlled laboratory study.

INTRODUCTION: Severe acute pancreatitis is associated with systemic inflammation, compensatory immune suppression, secondary infections, vital organ dysfunction, and death.Our study purpose was to delineate signaling profiles of circulating lymphocytes in acute pancreatitis complicated by organ dysfunction. METHODS: Sixteen patients with acute pancreatitis, dysfunction of vital organ(s), and immune suppression (proportion of HLA-DR Human Leukocyte Antigen - DR - positive monocytes < 80%) participated. Healthy volunteers served as reference subjects. Using phospho-specific whole blood flow cytometry we studied lymphocyte phosphorylation of nuclear factor-κB (NFκB), mitogen-activated protein kinases p38 and extracellular signal-regulated kinases (ERK)1/2, and signal transducers and activators of transcription (STATs) 1, 3, and 6. Statistical comparisons were performed with the Wilcoxon-Mann-Whitney test. RESULTS: In blood samples supplemented with tumor necrosis factor, E. coli or S. aureus, phosphorylation levels of NFκB were lower and levels of p38 were higher in patients with acute pancreatitis than healthy subjects. Low NFκB activation involved CD3+CD4+ and CD3+CD8+ lymphocytes. ERK1/2 phosphorylation induced by co-stimulation with phorbol 12-myristate 13-acetate and calcium ionophore A23187 was depressed in patients. STAT3 was constitutively activated in patients' CD3+CD4+ and CD3+CD8+ lymphocytes. Also, IL-6-induced STAT1 phosphorylation was impaired while IL-4-induced STAT6 phosphorylation was enhanced. CONCLUSIONS: Lymphocytes of patients with acute pancreatitis, organ dysfunction and immune suppression show impaired NFκB activation, which increases infection risk and enhanced p38 activation, which sustains inflammation. Secondly, they indicate constitutive STAT3 activation, which may favor Th17 lineage of CD4+ lymphocyte differentiation. Thirdly, they reveal impaired STAT1 activation and enhanced STAT6 activation, denoting a shift from Th1 towards Th2 differentiation.

Immunosupression and infection after major surgery: a nutritional deficiency.

T cell dysfunction significantly increases susceptibility to infections and organ failure after trauma or surgery (physical injury). This coincides with a persistent drop in arginine availability, a necessary amino acid for normal T cell function. Recent data led to the identification of a novel mechanism of T cell suppression caused by the depletion of arginine through the induction of arginase 1 (ARG1) in a specialized group of immature myeloid cells, now named myeloid-derived suppressor cells (MDSC). In addition to T cell dysfunction, arginine depletion leads to the decrease in nitric oxide (NO) production. Dietary therapy containing arginine at supraphysiologic concentrations along with other components such as omega-3 fat acids, antioxidants, nucleotides, and vitamin A is associated with improvement in T cell function, NO production, and a significant decrease in infection rates. The authors propose that a pathologic decrease in arginine availability is an identifiable nutrition deficiency syndrome that worsens outcomes if left untreated.

[Urosepsis and treatment]. / Urosepsis und Therapie.

Urosepsis is one of the most frequent sepsis entities. Mortality from urosepsis is nowadays mostly lower than from other entities. Sepsis syndrome is pathophysiologically characterized by a generalized infection and immune dysregulation. Exogenous microbiological and active or passive endogenous factors released from body cells initiate and accompany the immune dysregulation. Diagnosis and therapy of urosepsis need to be instigated as early as possible (within the first hour), in order to prevent cell and tissue damage in the early phase. For this reason a series of measures is started, aimed at achieving early control of the focus of infection, providing antibiotic treatment, and stabilizing respiratory and cardiovascular function in order to optimize tissue oxygenation. A significant clinical problem ensues due to increasing antibiotic resistance mainly of enterobacteria. The choice of antibiotic therefore is made on the basis of local antibiotic resistance statistics. Dosage is determined on an individual basis, as well as according to current pharmacokinetic/pharmacodynamic knowledge. The intensive care of the septic patient needs to be started as early as on patient admission and, where necessary, continued on the intensive care ward.

[Relationship between immune imbalance and sthenia-asthenia syndromes in patients suffering from severe intra-abdominal infection].

OBJECTIVE: To explore the characteristics of immune imbalance in patients with multiple organ dysfunction syndrome (MODS) induced by severe intra-abdominal infection and its relationship with changing of TCM sthenia-asthenia syndrome. METHODS: Forty-six patients with MODS induced by severe intra-abdominal infection and treated with etiological and syndrome differentiation of integrative medicine were observed in succession. Patients' peripheral blood levels of interleukin-6/interleukin-10 ratio (IL-6/IL-10), human leukocyte antigen DR site (HLA-DR), helper T lymphocyte1/2 ratio (Th1/Th2), and the regulatory T lymphocyte (Treg) were measured on the 1st, 3rd and 7th day of the research respectively. And the distribution laws of TCM syndrome types, sthenia (S), asthenia (A), and mingled sthenia/asthenia (M), in patients were observed as well. RESULTS: IL-6/IL-10 ratio at all the testing time points showed insignificant difference in patients of types S and M, while in those of type A, it was more lowered on the 7th day than that on the 1st day. HLA-DR lowered to <30% on the 7th day in all patients of type A and showed significant difference to that on the 1st day (P <0.05), while HLA-DR <30% was not found in all patients of types S and M. Th1/Th2 ratio in patients of types S and A was insignificant different at the foremost 3 days, but lowered significantly on the 7th day, while in patients of type M, it was unchanged in all the 7 days of observation. Treg level was unchanged in the foremost 3 days in patients of types S and M, while in those of type A, it raised on the 3rd day, but no raising was found in the subsequent 4 days. Comparisons of various indexes detected at corresponding time points respectively among patients with various syndrome types showed that, for levels of IL-6/IL-8, HLA-DR, and Th1/Th2, the sequence was S>M>A; and for Treg, it was A>M>S. CONCLUSION: In the pathological process of MODS induced by severe intra-abdominal infection, the index IL-6/IL-10, reflecting the balance of the pro-/anti-inflammatory cytokines and the indexes HLA-DR, Th1/Th2 and Treg reflecting the immune function, all can exactly reflect the TCM asthenia-sthenia syndrome types. The sequence in patients of various syndrome types for levels of IL-6/IL-10, HLA-DR and Th1/Th2, is S> M>A, but for Treg it is the inverse, as A>M>S.

Early enteral supplementation with key pharmaconutrients improves Sequential Organ Failure Assessment score in critically ill patients with sepsis: outcome of a randomized, controlled, double-blind trial.

OBJECTIVE: To assess the safety and efficacy of an early enteral pharmaconutrition supplement containing glutamine dipeptides, antioxidative vitamins and trace elements, and butyrate in critically ill, septic patients. DESIGN: A prospective, randomized, controlled, double-blind clinical trial. SETTING: Adult intensive care unit in a university hospital. PATIENTS: Fifty-five critically ill, septic patients requiring enteral feeding. INTERVENTIONS: Patients received either an enteral supplement (500 mL of Intestamin, Fresenius Kabi) containing conditionally essential nutrients or a control solution via the nasogastric route for up to 10 days. Inclusion occurred within 24 hrs of intensive care unit admission. Additionally, patients received enteral feeding with an immunonutrition formula (experimental group) or standard formula (control group) initiated within 48 hrs after enrollment. MEASUREMENTS AND MAIN RESULTS: Organ dysfunction was assessed by daily total Sequential Organ Failure Assessment (SOFA) score over the 10-day study period in both patient groups. Patients receiving the experimental supplement showed a significantly faster decline in the regression slopes of delta daily total SOFA score over time compared with control. The difference between the regression coefficients of the two slopes was significant irrespective of the level of analysis: intent to treat -0.32 vs. -0.14, p < .0001; per protocol -0.34 vs. -0.14, p < .0001; and completers (patients receiving > or = 80% of the calculated caloric target over a period of 6 days), -0.26 vs. -0.16, p = .0005. Vitamin C, as a marker of supplement absorption, increased from 10.6 (1.9-159.4) micromol/L (normal range 20-50 micromol/L) on day 1 to 58.7 (5.4-189.9) micromol/L by day 3 (p = .002) in the intervention group but remained below the normal range in the control group 17.0 (2.8-78.5) on day 1 and 14.3 (2.4-179.6) on day 3. Serum levels of glycine, serine, arginine, ornithine, vitamin E, and beta-carotene all increased significantly with treatment in the supplementation group. CONCLUSIONS: In medical patients with sepsis, early enteral pharmaconutrition with glutamine dipeptides, vitamin C and E, beta-carotene, selenium, zinc, and butyrate in combination with an immunonutrition formula results in significantly faster recovery of organ function compared with control.

Use of exogenous arginine in multiple organ dysfunction syndrome and sepsis.

Given the multiple biological, metabolic, and pharmacologic effects of supplemental arginine, much effort has been devoted to defining its role in numerous clinical conditions. Herein, we review the multiple pathways of arginine metabolism with its various enzyme systems; the effect of arginine on nutrition, healing, and immune system; and its clinical use. Sepsis has been postulated to be an arginine-deficient state and/or a syndrome with elevated levels of nitric oxide. So-called immunonutritional formulations containing various nutritional components have been used most often, yet the effects often are attributed to arginine alone. Such conclusions led to guidelines recommending against the use of arginine-supplemented diets in critically ill patients. While caution in the face of a lack of evidence for benefit in sepsis is commended, well-defined studies examining arginine monotherapy in the context of full nutritional support should be carried out so as to define the possible clinical uses of arginine in critically ill and septic patients.

Role of enteral nutrition supplemented with ebselen and EHEC in pancreatitis-associated multiple organ dysfunction in rats.

OBJECTIVES: To investigate potential effects of ebselen and ethylhydroxyethyl cellulose (EHEC) on the acute phase responses and the severity of multiple organ dysfunction associated with acute pancreatitis. METHODS: Acute pancreatitis was induced by intraductal infusion of 5% sodium taurodeoxycholate. The increase of total protein content in the BALF was used as an indication for acute lung injury, plasma amylase for pancreatic damage, plasma bilirubin for acute liver dysfunction, and plasma creatinine for acute kidney dysfunction. Levels of interleukin (IL)-6, macrophage inflammatory protein (MIP)-2 in the BALF were determined by ELISA. RESULTS: There was a dose-related tendency for ebselen or EHEC alone to prevent organ dysfunction and reduce elevated plasma levels of IL-6 and ICAM-1 expression on circulating leukocytes 12 h after AP induction. The combination of ebselen and EHEC significantly prevented pancreatitis-induced multiple organ injury, IL-6 production and ICAM-1 expression in rats and exhibited better effects than either monocompound alone. CONCLUSION: The combination of ebselen and EHEC may be a new potential for treatment of acute severe pancreatitis.

Pyrrolidine dithiocarbamate attenuates the development of organ failure induced by zymosan in mice.

OBJECTIVE: Nuclear factor (NF) kappaB is a transcription factor which plays a pivotal role in the induction of genes involved in physiological processes as well as in the response to injury and inflammation. Dithiocarbamates are anti-oxidants which are potent inhibitors of NF-kappaB. We postulated that pyrrolidine dithiocarbamate (PDTC) would attenuate multiple-organ failure (MOF). DESIGN AND SETTING: Rats in a university research laboratory. INTERVENTIONS AND MEASUREMENTS: We investigated the effects of PDTC (10 mg/kg) on the MOF caused by zymosan (500 mg/kg, administered i.p. as a suspension in saline) in mice. MOF in mice was assessed 18 h after administration of zymosan and/or PDTC and monitored for 7 days (for loss of body weight and mortality). RESULTS: Treatment of mice with PDTC (10 mg/kg i.p., 1 and 6 h after zymosan) attenuated the peritoneal exudation and the migration of polymorphonuclear cells caused by zymosan. PDTC also attenuated the lung, liver and pancreatic injury and renal dysfunction caused by zymosan as well as the increase in myeloperoxidase activity and malondialdehyde levels caused by zymosan in the lung, liver and intestine. Immunohistochemical analysis for inducible nitric oxide synthase, nitrotyrosine and poly(ADP-ribose) revealed positive staining in lung, liver and intestine tissues obtained from zymosan-treated mice. The degree of staining for nitrotyrosine and poly(ADP-ribose) were markedly reduced in tissue sections obtained from zymosan-treated mice which received PDTC. Furthermore, treatment of mice with PDTC significantly reduced the expression of nitric oxide synthase in lung, liver and intestine. CONCLUSIONS: This study provides the first evidence that PDTC attenuates the degree of zymosan-induced MOF in mice.

[Immune function and organ failure. Immunomodulation with nutritional support--an update]. / Immunfunktion und Organversagen. Immunmodulation durch Ernährungssubstrate--"update".

Today, substrates with immunomodulatory effects are not only identified in all groups of macronutrients, but also in the domains of vitamins and traceelements. Mainly they interfere with 3 areas of the immune response: 1. the mucosal barrier function, 2. the cellular defense function, and 3. the local or systemic inflammatory response. Enteral formulas enriched with immune-enhancing diets are already in clinical use to encounter "immunoparalysis" of cellular defense during critical illness. Considering defined outcome variables, indeed, current clinical studies point out some improvements. Using an evidence based approach, a grade A recommendation was proclaimed for its broad clinical use. For defined subgroups of patients, however, presenting with most severe appearances of SIRS and consecutive organ failure, the current concept of enteral immunonutrition remains to be a matter of debate, and the evidence of clinical benefits persist to be questionable.

Protective effect of N-acetylcysteine on multiple organ failure induced by zymosan in the rat.

BACKGROUND AND METHODS: In the present study, we evaluated the effect of N-acetylcysteine treatment in a nonseptic shock model induced by zymosan in the rat. Animals were randomly divided into eight groups (ten animals in each group). The first group was treated with ip administration of saline solution (0.90% NaCl) and served as the sham group. The second group was treated with ip administration of zymosan (500 mg/kg suspended in saline solution). In the third and fourth groups, rats received ip administration of N-acetylcysteine (40 mg/kg; 1 and 6 hrs after administration of zymosan or saline). In the fifth and sixth groups, rats received ip administration of N-acetylcysteine (20 mg/kg; 1 and 6 hrs after zymosan or saline administration). In the seventh and eighth groups, rats received ip administration of N-acetylcysteine (10 mg/kg; 1 and 6 hrs after zymosan or saline administration). After zymosan or saline injection, animals were monitored for the evaluation of systemic toxicity (conjunctivitis, ruffled fur, diarrhea, and lethargy), loss of body weight, and mortality for 72 hrs. Exudate formation, leukocyte infiltration, nitrate/nitrite production, lung and intestine myeloperoxidase activity and lipid peroxidation, and histologic examination were evaluated at 18 hrs after zymosan administration. RESULTS: Administration of zymosan in the rat induced acute peritonitis, as assessed by a marked increase in the leukocyte count in the exudate, as well as by an increase in the exudate nitrate/nitrite concentration. Lung and intestine myeloperoxidase activity and lipid peroxidation was significantly increased in zymosan-treated rats. This inflammatory process coincided with the damage of lung and small intestine. Peritoneal administration of zymosan in the rat also induced a significant increase in the plasma levels of nitrite and nitrate and stable metabolites of nitric oxide and in levels of peroxynitrite, as measured by the oxidation of the fluorescent dihydrorhodamine 123 at 18 hrs after zymosan challenge. Immunohistochemical examination demonstrated a marked increase in the immunoreactivity to nitrotyrosine, a specific "footprint" of peroxynitrite, in the lung of zymosan-shocked rats. Pretreatment of zymosan-shocked rats with ip administration of N-acetylcysteine (40, 20, and 10 mg/kg, 1 and 6 hrs after zymosan) prevented the development of peritonitis and reduced peroxynitrite formation in a dose-dependent manner. In addition, ip administration of N-acetylcysteine (40 mg/kg, 1 and 6 hrs after zymosan) was effective in preventing the development of lung and intestine injury and neutrophil infiltration, as determined by myeloperoxidase evaluation. CONCLUSIONS: Taken together, the present results demonstrate that N-acetylcysteine exerts potent anti-inflammatory effects.

Protective effect of poly(ADP-ribose) synthetase inhibition on multiple organ failure after zymosan-induced peritonitis in the rat.

BACKGROUND AND METHODS: In the present study, we tested the hypothesis that peroxynitrite and subsequent activation of the nuclear enzyme poly(ADP-ribose) synthetase (PARS) play a role in the pathogenesis of multiple organ failure induced by peritoneal injection of zymosan in the rat. Animals were randomly divided into six groups (ten rats for each group). The first group was treated with ip administration of saline solution (0.9% NaCl) and served as the sham group. The second group was treated with ip administration of zymosan (500 mg/kg suspended in saline solution). In the third and fourth groups, rats received ip administration of 3-aminobenzamide (10 mg/kg) 1 and 6 hrs after zymosan or saline administration, respectively. In the fifth and sixth groups, rats received ip administration of nicotinamide (50 mg/kg) 1 and 6 hrs after zymosan or saline administration, respectively. After zymosan or saline injection, animals were monitored for 72 hrs to evaluate systemic toxicity (conjunctivitis, ruffled fur, diarrhea, and lethargy), loss of body weight, and mortality. RESULTS: A severe inflammatory response, characterized by peritoneal exudation, high plasma and peritoneal levels of nitrate/nitrite (the breakdown products of nitric oxide), and leukocyte infiltration into peritoneal exudate, was induced by zymosan administration. This inflammatory process coincided with the damage of lung, small intestine, and liver as assessed by histologic examination and by an increase of myeloperoxidase activity, which is indicative of neutrophil infiltration. Zymosan-treated rats showed signs of systemic illness, significant loss of body weight, and high mortality rates. Peritoneal administration of zymosan in the rat also induced a significant increase in the plasma levels of peroxynitrite as measured by the oxidation of the fluorescent dihydrorhodamine 123. Immunohistochemical examination demonstrated a marked increase in the immunoreactivity to nitrotyrosine, a specific "footprint" of peroxynitrite, in the lung of zymosan-shocked rats. In vivo treatment with ip administration of 3-aminobenzamide (10 mg/kg, 1 and 6 hrs after zymosan injection) or nicotinamide (50 mg/kg, 1 and 6 hrs after zymosan injection) significantly decreased mortality, inhibited the development of peritonitis, and reduced peroxynitrite formation. In addition, PARS inhibitors were effective in preventing the development of organ failure because tissue injury and neutrophil infiltration, by myeloperoxidase evaluation, were reduced in the lung, small intestine, and liver. CONCLUSIONS: In conclusion, the major findings of our study are that peroxynitrite and the consequent PARS activation exert a role in the development of multiple organ failure and that PARS inhibition is an effective anti-inflammatory therapeutic tool.

Complement modulatory activity of bisbenzylisoquinoline alkaloids isolated from Isopyrum thalictroides--II. Influence on C3-9 reactions in vitro and antiinflammatory effect in vivo.

The main alkaloids isopyruthaline (It1), fangchinoline (It2) and isothalictrine (It3), isolated from Isopyrum thalictroides (L.) were investigated in complement-mediated reactions. The alkaloids influenced the alternative pathway (AP) activity in normal human serum (NHS). They enhanced the inhibitory action of complement activators--carrageenan (Car), zymosan (Zy), hydrogen peroxide (HP) and high temperature via classical pathway (CP) in NHS. Substances strongly potentiated the action of zymosan and cobra venom (CV) in guinea pig serum (GPS). It was established that they could provoke C3 conversion in NHS and mouse sera (MS). The antiinflammatory properties of the alkaloids were evaluated in mouse paw oedema induced by CV, Zy and histamine (His). Isopyruthaline and isothalictrine suppressed paw swelling in CV- and Zy-oedema. They were applied in Zy-induced multiple organ dysfunction syndrome (MODS) in mice. The alkaloids inhibited the increase of the serum complement activity provoked by the injection of zymosan. Itl lowered the mortality rate of mice with MODS if its application proceeded Zy. An increase of the number of mice without tissue injury was established after treatment with It1 and It3.