Hemorrhage increases cytokine expression in lung mononuclear cells in mice: involvement of catecholamines in nuclear factor-kappaB regulation and cytokine expression

Hold Breath: Autonomic Neural Regulation of Innate Immunity to Defend Against SARS-CoV-2 Infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel member of the genus of betacoronavirus, which caused a pandemic of coronavirus disease 2019 (COVID-19) worldwide. The innate immune system plays a critical role in eliminating the virus, which induces inflammatory cytokine and chemokine secretion, produces different interferons, and activates the adaptive immune system. Interactions between the autonomic nervous system and innate immunity release neurotransmitters or neuropeptides to balance the excess secretion of inflammatory cytokines, control the inflammation, and restore the host homeostasis. However, more neuro-immune mechanisms to defend against viral infection should be elucidated. Here, we mainly review and provide our understanding and viewpoint on the interaction between respiratory viral proteins and host cell receptors, innate immune responses to respiratory viral infection, and the autonomic neural regulation of the innate immune system to control respiratory viruses caused by lungs and airways inflammation.

Protective effect of Apremilast against LPS-induced acute lung injury via modulation of oxidative stress and inflammation: Possible involvement of Akt and ERK signaling pathways

Lung injuries are attributed due to exposure to Drugs or chemicals. One of the important challenging situations for the clinicians is to manage treatments of different diseases with acute lung injury (ALI). The objective of this study was to investigate the possible protective mechanisms and action of a novel Phosphodiesterase-4 inhibitor “Apremilast” (AP) in lipopolysaccharide (LPS)-induced lung injury. Blood sample from each animals were collected in a vacuum blood collection tube. The rat lungs were isolated for oxidative stress assessment, western blot analysis and their mRNA expressions using RT-PCR. Exposure of LPS in rats causes significant increase in oxidative stress, activates the pro-inflammatory cytokines release like tissue necrotic factor-alpha (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6), modulated gene expression, protein expression and histopathological changes which were reversed by administration of AP. Finding of the research enlighten the protective role of AP against LPS-induced ALI.

In-Depth Characterization of the Effects of Cigarette Smoke Exposure on the Acute Trauma Response and Hemorrhage in Mice

INTRODUCTION

Hemorrhagic shock accounts for a large amount of trauma-related mortality. The severity of trauma can be further aggravated by an additional blunt chest trauma (TxT), which independently contributes to mortality upon the development of an acute lung injury (ALI). Besides, cigarette smoke (CS) exposure before TxT enhanced posttraumatic inflammation, thereby aggravating ALI. We therefore aimed to characterize the impact of an acute and/or chronic lung injury on organ dysfunction in a murine model of traumatic hemorrhagic shock (HS).

METHODS

After 3 weeks of CS exposure, anesthetized mice underwent HS with/without TxT. Hemorrhagic shock was implemented for 1 h followed by retransfusion of shed blood and intensive care therapy for 4 h including lung-protective mechanical ventilation, fluid resuscitation, and noradrenaline titrated to maintain mean arterial pressure ≥50 mmHg. Lung mechanics and gas exchange were assessed together with systemic hemodynamics, metabolism, and acid-base status. Postmortem blood and tissue samples were analyzed for cytokine and chemokine levels, protein expression, mitochondrial respiration, and histological changes.

RESULTS

CS exposure and HS alone coincided with increased inflammation, decreased whole blood sulfide concentrations, and decreased diaphragmatic mitochondrial respiration. CS-exposed mice, which were subjected to TxT and subsequent HS, showed hemodynamic instability, acute kidney injury, and high mortality.

CONCLUSIONS

Chronic CS exposure per se had the strongest impact on inflammatory responses. The degree of inflammation was similar upon an additional TxT, however, mice presented with organ dysfunction and increased mortality rates. Hence, in mice the degree of inflammation may be dissociated from the severity of organ dysfunction or injury.

Crystalloid fluid choice in the critically ill : Current knowledge and critical appraisal

Intravenous infusion of crystalloid solutions is one of the most frequently administered medications worldwide. Available crystalloid infusion solutions have a variety of compositions and have a major impact on body systems; however, administration of crystalloid fluids currently follows a "one fluid for all" approach than a patient-centered fluid prescription. Normal saline is associated with hyperchloremic metabolic acidosis, increased rates of acute kidney injury, increased hemodynamic instability and potentially mortality. Regarding balanced infusates, evidence remains less clear since most studies compared normal saline to buffered infusion solutes.; however, buffered solutes are not homogeneous. The term "buffered solutes" only refers to the concept of acid-buffering in infusion fluids but this does not necessarily imply that the solutes have similar physiological impacts. The currently available data indicate that balanced infusates might have some advantages; however, evidence still is inconclusive. Taking the available evidence together, there is no single fluid that is superior for all patients and settings, because all currently available infusates have distinct differences, advantages and disadvantages; therefore, it seems inevitable to abandon the "one fluid for all" strategy towards a more differentiated and patient-centered approach to fluid therapy in the critically ill.

β-Blockade use for Traumatic Injuries and Immunomodulation: A Review of Proposed Mechanisms and Clinical Evidence

Sympathetic nervous system activation and catecholamine release are important events following injury and infection. The nature and timing of different pathophysiologic insults have significant effects on adrenergic pathways, inflammatory mediators, and the host response. Beta adrenergic receptor blockers (β-blockers) are commonly used for treatment of cardiovascular disease, and recent data suggests that the metabolic and immunomodulatory effects of β-blockers can expand their use. β-blocker therapy can reduce sympathetic activation and hypermetabolism as well as modify glucose homeostasis and cytokine expression. It is the purpose of this review to examine either the biologic basis for proposed mechanisms or to describe current available clinical evidence for the use of β-blockers in traumatic brain injury, spinal cord injury, hemorrhagic shock, acute traumatic coagulopathy, erythropoietic dysfunction, metabolic dysfunction, pulmonary dysfunction, burns, immunomodulation, and sepsis.

Manipulating the immune system for pigs to optimise performance

Disease and enhanced microbial load are considered to be major factors limiting the performance and overall efficiency of feed use by pigs in Australian piggeries. It is recognised that pigs exposed to conventional housing systems with high microbial loads grow 10–20% more slowly than do gnotobiotic pigs or pigs kept in ‘clean’ environments. Consequently, a proportion of pigs in any production cycle are continuously being challenged by their immediate environment, which can cause an immune response to be mounted. Such a process is physiologically expensive in terms of energy and protein (comprised of amino acids), with, for example, the enhanced rate of protein turnover associated with the production of immune cells, antibodies and acute-phase proteins increasing energy expenditure by 10–15% of maintenance needs and protein requirements by 7–10%. The requirements for lysine, tryptophan, sulfur-containing amino acids and threonine can be increased by a further 10%. The over-stimulation of the immune response with excess production of pro-inflammatory cytokines causes excessive production primarily of the prostaglandin E2 (PGE2), which contributes to anorexia, fever and increased proteolysis, and a concomitant reduction in pig performance. Prostaglandin E2 is produced from dietary and cell-membrane phospholipids via secretory phospholipase A2 (sPLA2) to produce arachidonic acid, which is catalysed by the COX-2 enzyme. Negating the negative effects of PGE2 appears not to adversely affect the ability of the immune system to combat pathogens, but improves pig performance. There are negative outcomes for pig health and productivity through both under- and over-stimulation of the immune response. This review briefly outlines the impact of immune stimulation on pigs and discusses strategies to optimise the immune response for pig health and performance.

Hyperoxygenated hydrogen-rich solution suppresses shock- and resuscitation-induced liver injury

BACKGROUND

It is not known whether simultaneous delivery of hydrogen and oxygen can reduce injury caused by hemorrhagic shock and resuscitation (HSR). This study investigated the therapeutic potential of hyperoxygenated hydrogen-rich solution (HHOS), a combined hydrogen/oxygen carrier, in a rat model of HSR-induced liver injury.

MATERIALS AND METHODS

Rats (n = 60) were randomly divided into 5 groups (n = 6 per group at each time point). One group underwent sham operation, and the others were subjected to severe hemorrhagic shock and then treated with lactated Ringer's solution (LRS), hydrogen-rich solution, hyperoxygenated solution, or HHOS. At 2 and 6 h after resuscitation, blood samples (n = 6) were collected from the femoral artery and serum concentrations of alanine aminotransferase and aspartate aminotransferase (AST) were measured. Rats were then sacrificed, and histopathological changes in the liver were evaluated by quantifying the percentage of apoptotic cells by caspase-3 immunohistochemistry and terminal deoxynucleotidyl transferase dUTP nick-end labeling. Inflammation was assessed by assessing malondialdehyde content and tumor necrosis factor-α, and interleukin (IL)-6 expression.

RESULTS

Compared to lactated Ringer's solution, hydrogen-rich solution, or hyperoxygenated solution groups, serum AST and alanine aminotransferase levels and IL-6, tumor necrosis factor-α, and malondialdehyde expression in liver tissue were decreased by HHOS treatment. The number of caspase-3- and terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells was decreased (P < 0.05) by HHOS treatment, 2 and 6 h after resuscitation.

CONCLUSIONS

HHOS has protective effects against liver injury in a rat model of HSR.

Adrenergic regulation during acute hepatic infection with Entamoeba histolytica in the hamster: involvement of oxidative stress, Nrf2 and NF-KappaB

Oxidative stress and transcriptional pathways of nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor kappa-B (NF-κB) are critically involved in the etiopathology of amebic liver abscess (ALA). In this work, we studied the relationship between the adrenergic nervous system and ALA in the hamster. ALA was visible at 12 h of infection. While 6-hydroxidopamine (6-OHDA) decreased infection, propranolol (β-adrenergic blocker) treatment was associated with less extensive liver damage, and phentolamine treatment (α-adrenergic blocker) significantly reduced ALA compared to 6-OHDA and propranolol. Serum enzymatic activities of alanine aminotransferase (ALT) and γ-glutamyl transpeptidase (γ-GTP) were increased at 12 h post-infection. Chemical denervation and α and β-adrenergic blockers decreased ALT to normal levels, while 6-OHDA and propranolol showed a trend to decrease γ-GTP but phentolamine significantly reduced γ-GTP. Amebic infection increased oxidized glutathione (GSSG) and decreased both reduced glutathione (GSH) and the GSH/GSSG ratio. Propranolol and 6-OHDA showed a tendency to decrease GSSG. However, GSH, GSSG and GSH/GSSG returned to normal levels with phentolamine. Furthermore, amebic infection increased pNF-κB and interleukin-1β (IL-1β), and showed a tendency to decrease hemoxigenase-1 (HO-1), but not Nrf2. Chemical denervation showed a trend to decrease pNF-κB and IL-1β, and neither Nrf2 nor HO-1 increased significantly. In addition, NF-κB and IL-1β were attenuated by propranolol and phentolamine treatments, although phentolamine showed significant overexpression of Nrf2 and HO-1. This suggests that the adrenergic system may be involved in oxidative stress and in modulation of the Nrf2 and NF-κB pathways during ALA development.

Fine Particulate Matter and Sulfur Dioxide Coexposures Induce Rat Lung Pathological Injury and Inflammatory Responses Via TLR4/p38/NF-κB Pathway

Fine particulate matter (PM_2.5) and sulfur dioxide (SO₂) are 2 common air pollutants, but their toxicological effects of coexposure are still not fully clear. In this study, SO₂ exposure (5.6 mg/m³) couldn't cause obvious inflammatory responses in rat lungs. The PM_2.5 exposure (1.5 mg/kg body weight) increased inflammatory cell counts in bronchoalveolar lavage fluid (BALF) and some inflammation damage. Importantly, SO₂ and PM_2.5 (1.5, 6.0, and 24.0 mg/kg) coexposure induced pathological and ultrastructural damage and raised inflammatory cells in BALF compared with the control. Also, they significantly elevated the levels of pro-inflammatory cytokines, adhesion molecule, and nitric oxide (NO) and promoted the gene expression of nuclear factor kappa B (NF-κB), phosphorylated p38 (p-p38), and Toll-like receptor 4 (TLR4) in rat lungs treated with higher dose of PM_2.5 (6.0 and 24.0 mg/kg) plus SO₂ relative to the control or SO₂ group, along with the decreased inhibitor of NF-κBα and increased inhibitor of NF-κB kinase β expressions. The changes in the inflammatory markers in the presence of PM_2.5 plus SO₂ were not significant compared with the PM_2.5 group. The results indicated that inflammatory injury and pathological and ultrastructural damage in rat lungs exposed to PM_2.5 plus SO₂ were involved in TLR4/p38/NF-κB pathway activation accompanied by oversecretion of pro-inflammatory cytokine, adhesion molecule, and NO. It provides more useful evidence to understand the possible toxicological mechanism that PM_2.5 and SO₂ copollution exacerbate lung disease.

Iso-osmolar prehydration shifts the cytokine response towards a more anti-inflammatory balance in human endotoxemia

Clinical experience suggests that the administration of fluids in human endotoxemia reduces symptoms. In the present study, the effects of a standardised fluid protocol on symptoms, inflammatory and hemodynamic parameters in human endotoxemia are determined. With approval of the local ethics committee, 16 healthy volunteers received 2 ng/kg of Escherichia coli endotoxin (O:113). After an overnight fast, nine subjects received 1.5 l of 2.5% glucose/0.45% NaCl the hour prior to the endotoxin administration and 150 ml/h during the course of the experiment (`prehydrated group'). Seven subjects only received a continuous infusion of 75 ml/h during the experiment (`non-prehydrated group'). The course of inflammatory parameters and symptoms were determined and mean arterial pressure, heart rate and forearm blood flow were measured. In the prehydrated group, TNF-α increased to 522 ± 63 pg/ml (mean ± SEM) while the maximum in the non-prehydrated group was 927 ± 187 pg/ml ( P < 0.04). IL-10 increased similarly in both groups (non-prehydrated 117 ± 18 pg/ml and prehydrated 99 ± 18 pg/ml; P = NS). The prehydrated group had a significantly lower ( P < 0.004) symptom score and recovered sooner ( P = 0.004). Endotoxin-induced changes in hemodynamics revealed no significant differences between groups. We demonstrate that prehydration in experimental human endotoxemia significantly shifts the cytokine balance towards a more anti-inflammatory pattern. This effect is associated with a reduction in symptoms, whereas the changes in hemodynamic parameters are not influenced by prehydration.

Inflammation and Edema in the Lung and Kidney of Hemorrhagic Shock Rats Are Alleviated by Biliary Tract External Drainage via the Heme Oxygenase-1 Pathway

The lung and kidney are two organs that are easily affected by hemorrhagic shock (HS). We investigated roles of biliary tract external drainage (BTED) in inflammation and edema of the lung and kidney in HS and its relationship with the heme oxygenase-1 (HO-1) pathway. Rat models of HS were induced by drawing blood from the femoral artery until a mean arterial pressure (MAP) of 40 ± 5 mmHg was achieved. A MAP of 40 ± 5 mmHg was maintained for 60 min. Thirty-six Sprague-Dawley rats were randomized to the following groups: sham group; HS group; HS + zinc protoporphyrin IX (ZnPP), a specific HO-1 inhibitor, group; HS + BTED group; HS + BTED + ZnPP group; and HS + BTED + bile infusion (BI) group. HO-1 levels, aquaporin-1 levels, and ratios of dry/wet in the lung and kidney increased markedly after BTED, but tumor necrosis factor-α and myeloperoxidase levels in the lung and kidney decreased significantly after BTED under HS conditions. Under the condition that HO-1 was inhibited by ZnPP, all these effects induced by BTED disappeared in the lung and kidney. These results demonstrated that inflammation and edema of the lung and kidney of HS rats are alleviated by BTED via the HO-1 pathway.

Inhaled hydrogen ameliorates endotoxin-induced bowel dysfunction

Aim

Gastrointestinal dysmotility frequently occurs during sepsis and multiple organ failure, remaining a major cause of morbidity and mortality in critically ill patients. Previous studies have shown that hydrogen, a new therapeutic gas, can improve various organ damage associated with sepsis. In this study, we investigated the protective efficacies of inhaled hydrogen against lipopolysaccharide (LPS)‐induced ileus.

Methods

Sepsis was induced in rats and mice by a single i.p. injection of LPS at 15 mg/kg for mice and 5 mg/kg for rats. Four groups of rats and mice including sham/air, sham/hydrogen, LPS/air, and LPS/hydrogen were analyzed. Hydrogen (1.3%) was inhaled for 25 h beginning at 1 h prior to LPS treatment. Gastrointestinal transit was quantified and cytokine levels, as well as neutrophil extravasation, in the intestinal muscularis propria were determined.

Results

Lipopolysaccharide challenge remarkably delayed gastrointestinal transit of non‐absorbable dextran, associated with increased leukocyte recruitment and upregulation of pro‐inflammatory cytokine mRNA expressions in the muscularis propria. Hydrogen significantly prevented LPS‐induced bowel dysmotility and reduced leukocyte extravasation, as well as inhibition of inflammatory cytokine expression. In vitro analysis of cytokine levels after LPS treatment of cultured macrophages showed an increase of interleukin‐10 by hydrogen regardless of the presence of nitric oxide.

Conclusions

This study showed the protective effects of hydrogen inhalation on LPS‐induced septic ileus through inhibition of inflammation in the muscularis propria. These inhibitory effects on the pro‐inflammatory response may be partially derived from anti‐inflammatory cytokine interleukin‐10 induction.

The Protective Mechanism of Fluorofenidone in Renal Interstitial Inflammation and Fibrosis

BACKGROUND

Deregulated inflammation has been implicated in the development of renal interstitial fibrosis and progressive renal failure. Previous work has established that fluorofenidone, a pyridone agent, attenuates renal fibrosis. However, the mechanism by which fluorofenidone prevents renal fibrosis remains unclear. The aim of this study was to investigate the in vivo effects of fluorofenidone on unilateral ureteral obstruction-induced fibrosis and the involved molecular mechanism in mouse peritoneal macrophages.

METHODS

Renal fibrosis was induced in rat by unilateral ureteral obstruction for 3, 7 or 14 days. Ipsilateral kidneys were harvested for morphologic analysis. Leukocyte infiltration was assessed by immunohistochemistry staining. The expression of chemokines (MCP-1, RANTAS, IP-10, MIP-1α and MIP-1β) and pro-inflammatory cytokines (TNF-α and IL-1β) was measured by enzyme-linked immunosorbent assay and real-time polymerase chain reaction. Mouse peritoneal macrophages and HK-2 cells were incubated with necrotic MES-13 cells or TNF-α in the presence or absence of fluorofenidone. The production of MCP-1 was measured by enzyme-linked immunosorbent assay, and phosphorylation of ERK1/2, p38 and JNK was quantified by Western blot.

RESULTS

Fluorofenidone treatment hampered renal pathologic change and interstitial collagen deposition. Leukocyte infiltration and the expression of chemokines (MCP-1, RANTES, IP-10, MIP-1α and MIP-1β) and pro-inflammatory cytokines (IL-1α) in kidney were significantly reduced by fluorofenidone treatment. Mechanistically, fluorofenidone significantly inhibited TNF-α or necrotic cell-induced activation of MAP kinase pathways in vitro.

CONCLUSIONS

Fluorofenidone serves as a novel anti-inflammatory agent that attenuates ureteral obstruction-induced renal interstitial inflammation and fibrosis, possibly through the inhibition of the microtubule-associated protein kinase pathways.

Comparison of Bacterial Burden and Cytokine Gene Expression in Golden Hamsters in Early Phase of Infection with Two Different Strains of Leptospira interrogans

Leptospirosis, a zoonotic infection with worldwide prevalence, is caused by pathogenic spirochaetes of Leptospira spp., and exhibits an extremely broad clinical spectrum in human patients. Although previous studies indicated that specific serovars or genotypes of Leptospira spp. were associated with severe leptospirosis or its outbreak, the mechanism underlying the difference in virulence of the various Leptospira serotypes or genotypes remains unclear. The present study addresses this question by measuring and comparing bacterial burden and cytokine gene expression in hamsters infected with strains of two L. interrogans serovars Manilae (highly virulent) and Hebdomadis (less virulent). The histopathology of kidney, liver, and lung tissues was also investigated in infected hamsters. A significantly higher bacterial burden was observed in liver tissues of hamsters infected with serovar Manilae than those infected with serovar Hebdomadis (p < 0.01). The average copy number of the leptospiral genome was 1,302 and 20,559 in blood and liver, respectively, of hamsters infected with serovar Manilae and 1,340 and 4,896, respectively, in hamsters infected with serovar Hebdomadis. The expression levels of mip1alpha in blood; tgfbeta, il1beta, mip1alpha, il10, tnfalpha and cox2 in liver; and tgfbeta, il6, tnfalpha and cox2 in lung tissue were significantly higher in hamsters infected with serovar Manilae than those infected with serovar Hebdomadis (p < 0.05). In addition, infection with serovar Manilae resulted in a significantly larger number of hamsters with tnfalpha upregulation (p = 0.04). Severe distortion of tubular cell arrangement and disruption of renal tubules in kidney tissues and hemorrhage in lung tissues were observed in Manilae-infected hamsters. These results demonstrate that serovar Manilae multiplied more efficiently in liver tissues and induced significantly higher expression of genes encoding pro- and anti-inflammatory cytokines than serovar Hebdomadis even in tissues for which a significant difference in leptospiral load was not observed. In addition, our results suggest a serovar Manilae-specific mechanism responsible for inducing severe damage in kidneys and hemorrhage in lung.

Hydrogen inhalation protects against acute lung injury induced by hemorrhagic shock and resuscitation

INTRODUCTION

Hemorrhagic shock followed by fluid resuscitation (HS/R) triggers an inflammatory response and causes pulmonary inflammation that can lead to acute lung injury (ALI). Hydrogen, a therapeutic gas, has potent cytoprotective, antiinflammatory, and antioxidant effects. This study examined the effects of inhaled hydrogen on ALI caused by HS/R.

METHODS

Rats were subjected to hemorrhagic shock by withdrawing blood to lower blood pressure followed by resuscitation with shed blood and saline to restore blood pressure. After HS/R, the rats were maintained in a control gas of similar composition to room air or exposed to 1.3% hydrogen.

RESULTS

HS/R induced ALI, as demonstrated by significantly impaired gas exchange, congestion, edema, cellular infiltration, and hemorrhage in the lungs. Hydrogen inhalation mitigated lung injury after HS/R, as indicated by significantly improved gas exchange and reduced cellular infiltration and hemorrhage. Hydrogen inhalation did not affect hemodynamic status during HS/R. Exposure to 1.3% hydrogen significantly attenuated the upregulation of the messenger RNAs for several proinflammatory mediators induced by HS/R. Lipid peroxidation was reduced significantly in the presence of hydrogen, indicating antioxidant effects.

CONCLUSION

Hydrogen, administered through inhalation, may exert potent therapeutic effects against ALI induced by HS/R and attenuate the activation of inflammatory cascades.

Different impacts of α- and β-blockers in neurogenic hypertension produced by brainstem lesions in rat

BACKGROUND

Bilateral lesions of nucleus tractus solitarii in rat result in acute hypertension, pulmonary edema, and death within hours. The hypertension results from excessive catecholamine release. Catecholamine can activate connexin43 to regulate cell death. There is no study investigating the cardiopulmonary impacts of different adrenergic blockers and apoptosis mechanism in rat model.

METHODS

The authors microinjected 6-hydroxydopamine into nucleus tractus solitarii of the rat (n = 8 per group) and evaluated the cardiopulmonary changes after treatment with different concentrations of α1-blockers, α2-blockers, β-blockers, and α-agonists.

RESULTS

In the rat model, the authors found that prazosin (0.15 mg/kg) treatment could preserve cardiac output and reverse neutrophil infiltrations in lungs and lead to prevent pulmonary hemorrhagic edema. The time-dependent increases in connexin43 and terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells induced by 6-hydroxydopamine lesions were decreased after prazosin treatment (terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells at 6 h: 64.01 ± 2.41% vs. 24.47 ± 3.10%; mean ± SD, P < 0.001, in heart, and 80.83 ± 2.52% vs. 2.60 ± 1.03%, P < 0.001, in lung). However, propranolol caused further compromise of the already impaired cardiac output with consequence of rapid death. Phenylephrine enhanced the phenotype in the link between connexin43 expressions and terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells but not yohimbine. Connexin43 expressions and terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells were more decreased with prazosin (0.15 and 0.3 mg/kg) than that with prazosin (0.05 mg/kg) treatment.

CONCLUSIONS

α1-Receptors are the keystones of the phenotype. In some brainstem encephalitis and brain injury with nucleus tractus solitarii involvement, early α1-receptor blockade treatment may prevent acute death from tissue apoptosis. α-Blockers can also decrease cerebral perfusion pressure, and further studies are needed in translation to brain injury with increased intracranial pressure.

Do all β-blockers attenuate the excess hematopoietic progenitor cell mobilization from the bone marrow following trauma/hemorrhagic shock?

BACKGROUND

Severe injury results in increased mobilization of hematopoietic progenitor cells (HPC) from the bone marrow (BM) to sites of injury, which may contribute to persistent BM dysfunction after trauma. Norepinephrine is a known inducer of HPC mobilization, and nonselective β-blockade with propranolol has been shown to decrease mobilization after trauma and hemorrhagic shock (HS). This study will determine the role of selective β-adrenergic receptor blockade in HPC mobilization in a combined model of lung contusion (LC) and HS.

METHODS

Male Sprague-Dawley rats were subjected to LC, followed by 45 minutes of HS. Animals were then randomized to receive atenolol (LCHS + β1B), butoxamine (LCHS + β2B), or SR59230A (LCHS + β3B) immediately after resuscitation and daily for 6 days. Control groups were composed of naive animals. BM cellularity, %HPCs in peripheral blood, and plasma granulocyte-colony stimulating factor levels were assessed at 3 hours and 7 days. Systemic plasma-mediated effects were evaluated in vitro by assessment of BM HPC growth. Injured lung tissue was graded histologically by a blinded reader.

RESULTS

The use of β2B or β3B following LCHS restored BM cellularity and significantly decreased HPC mobilization. In contrast, β1B had no effect on HPC mobilization. Only β3B significantly reduced plasma G-CSF levels. When evaluating the plasma systemic effects, both β2B and β3B significantly improved BM HPC growth as compared with LCHS alone. The use of β2 and β3 blockade did not affect lung injury scores.

CONCLUSION

Both β2 and β3 blockade can prevent excess HPC mobilization and BM dysfunction when given after trauma and HS, and the effects seem to be mediated systemically, without adverse effects on subsequent healing. Only treatment with β3 blockade reduced plasma G-CSF levels, suggesting different mechanisms for adrenergic-induced G-CSF release and mobilization of HPCs. This study adds to the evidence that therapeutic strategies that reduce the exaggerated sympathetic stimulation after severe injury are beneficial and reduce BM dysfunction.

The rapid and sustained responses of dendritic cells to influenza virus infection in a non-human primate model

Dendritic cells (DCs) are readily infected by influenza viruses and play a crucial role in regulating host innate and adaptive immune responses to viral infection. The aims of this study are to characterize the dynamic changes in the numbers and maturation status of dendritic cells present in the lung and lung-associated lymph nodes (LALNs) in the model of a non-human primate (NHP) infected by influenza A virus (IAV). Cynomolgus macaques were infected with influenza A virus (H3N2) via bronchoscopy. Flow cytometry was used to analyze the DC numbers, maturation status and subsets during the time of acute infection (days 1, 2, 3, 4, 7) and the resolution phase (day 30). A dramatic increase in the numbers of influenza A virus-infected CD11c+CD14- myeloid dendritic cells (mDCs) and CD11c-CD123+ plasmacytoid dendritic cells (pDCs) were observed from day 1 to day 4 and peak up from day 7 post-infection. In lung and lung-associated lymph nodes, the numbers and maturation status of myeloid dendritic cells and plasmacytoid dendritic cells increased more slowly than those in the lung tissues. On day 30 post-infection, influenza A virus challenge increased the number of myeloid dendritic cells, but not plasmacytoid dendritic cells, compared with baseline. These findings indicate that dendritic cells are susceptible to influenza A virus infection, with the likely purpose of increasing mature myeloid dendritic cells numbers in the lung and lung and lung-associated lymph nodes, which provides important new insights into the regulation of dendritic cells in a non-human primate model.

Neuroendocrine immunoregulation in multiple sclerosis

Currently, it is generally accepted that multiple sclerosis (MS) is a complex multifactorial disease involving genetic and environmental factors affecting the autoreactive immune responses that lead to damage of myelin. In this respect, intrinsic or extrinsic factors such as emotional, psychological, traumatic, or inflammatory stress as well as a variety of other lifestyle interventions can influence the neuroendocrine system. On its turn, it has been demonstrated that the neuroendocrine system has immunomodulatory potential. Moreover, the neuroendocrine and immune systems communicate bidirectionally via shared receptors and shared messenger molecules, variously called hormones, neurotransmitters, or cytokines. Discrepancies at any level can therefore lead to changes in susceptibility and to severity of several autoimmune and inflammatory diseases. Here we provide an overview of the complex system of crosstalk between the neuroendocrine and immune system as well as reported dysfunctions involved in the pathogenesis of autoimmunity, including MS. Finally, possible strategies to intervene with the neuroendocrine-immune system for MS patient management will be discussed. Ultimately, a better understanding of the interactions between the neuroendocrine system and the immune system can open up new therapeutic approaches for the treatment of MS as well as other autoimmune diseases.

Is the sympathetic system involved in shock-induced gut and lung injury?

BACKGROUND

β-blockade (BB) has been shown to prevent bone marrow (BM) dysfunction after trauma and hemorrhagic shock (HS). The impact of the sympathetic system and the role of BB on shock-induced distant organ injury is not known. This study will determine if BB has systemic effects and can diminish gut and lung injury after trauma and HS.

METHODS

Male Sprague-Dawley rats were subjected to lung contusion (LC) followed by 45 minute of HS. Animals (n = 6 per group) were then randomized to either receive propranolol (LCHS + BB) immediately after resuscitation or not (LCHS). Gut permeability was evaluated in by diffusion of Mr 4,000 of fluorescein dextran (FD4) from a segment of small bowel into peripheral blood. Villous injury and lung injury were graded histologically by a blinded reader. Plasma-mediated effects of BB were evaluated in vitro by an assessment of BM progenitor growth.

RESULTS

Animals undergoing LCHS had significantly higher plasma levels of FD4 compared with control animals (mean [SEM], 2.8 [0.4] µg/mL vs. 0.8 [0.2] µg/mL). However, animals receiving BB had a significant reduction in plasma FD4 compared with the LCHS group. With the use of BB after LCHS, both ileal and lung injury scores were similar to control. In addition, BM progenitor growth was inhibited by the addition of LCHS plasma, and LCHS + BB plasma showed no inhibition of BM progenitor growth.

CONCLUSION

Propranolol can protect against the detrimental effects of trauma and HS on gut permeability, villous, and lung injury. The effects of BB are likely systemic and appear to be mediated through plasma. BB likely blunts the exaggerated sympathetic response after shock and injury. Propranolol's reduction of both BM dysfunction and distant organ injury further demonstrates the importance of the sympathetic nervous system and its role in potentiating end organ dysfunction after severe trauma.

Inhibition of Rho-kinase attenuates endothelial-leukocyte interaction during ischemia-reperfusion injury

Resuscitation from hemorrhagic shock induces endothelial dysfunction and activates inflammatory cascades leading to organ damage. Following restoration of blood flow to ischemic vascular beds, leukocyte-endothelium interactions leading to leukocyte infiltration into the vascular wall occur very early due, in part, to the loss of endothelium-derived nitric oxide (NO). The mechanism by which ischemia-reperfusion injury impairs endothelium-derived NO is not completely understood. We hypothesized that inhibition of Rho-kinase could exert beneficial effects following hemorrhagic shock by preserving endothelial function and attenuating leukocyte trafficking in the microcirculation. Using intravital microscopy, we found that resuscitation from hemorrhage acutely increased the number of rolling and adherent leukocytes in the mouse splanchnic microcirculation. Treatment of mice with the Rho-kinase inhibitor fasudil, markedly attenuated leukocyte-endothelium interaction in response to hemorrhage/reinfusion. The beneficial effect of fasudil was not observed in endothelial nitric oxide synthase (eNOS)(-/-) mice. In conclusion, inhibition of Rho-kinase prevents inflammatory leukocyte trafficking in the microcirculation via an eNOS-dependent mechanism. Our data support a role for Rho-kinase inhibitors in the treatment of ischemia-reperfusion injury.

Melanocortins and the cholinergic anti-inflammatory pathway

Experimental evidence indicates that small concentrations of inflammatory molecules produced by damaged tissues activate afferent signals through ascending vagus nerve fibers, that act as the sensory arm of an "inflammatory reflex". The subsequent activation of vagal efferent fibers, which represent the motor arm of the inflammatory reflex, rapidly leads to acetylcholine release in organs of the reticuloendothelial system. Acetylcholine interacts with α7 subunit-containing nicotinic receptors in tissue macrophages and other immune cells and rapidly inhibits the synthesis/release of tumor necrosis factor-α and other inflammatory cytokines. This neural anti-inflammatory response called "cholinergic anti-inflammatory pathway" is fast and integrated through the central nervous system. Preclinical studies are in progress, with the aim to develop therapeutic agents able to activate the cholinergic anti-inflammatory pathway. Melanocortin peptides bearing the adrenocorticotropin/α-melanocyte-stimulating hormone sequences exert a protective and life-saving effect in animals and humans in conditions of circulatory shock. These neuropeptides are likewise protective in other severe hypoxic conditions, such as prolonged respiratory arrest, myocardial ischemia, renal ischemia and ischemic stroke, as well as in experimental heart transplantation. Moreover, experimental evidence indicates that melanocortins reverse circulatory shock, prevent myocardial ischemia/reperfusion damage and exert neuroprotection against ischemic stroke through activation of the cholinergic anti-inflammatory pathway. This action occurs via stimulation of brain melanocortin MC3/MC4 receptors. Investigations that determine the molecular mechanisms of the cholinergic anti-inflammatory pathway activation could help design of superselective activators of this pathway.

Minocycline ameliorates lung and liver dysfunction in a rodent model of hemorrhagic shock/resuscitation plus abdominal compartment syndrome

BACKGROUND

We sought to elucidate whether minocycline, a broad-spectrum tetracycline antibiotic with potent anti-inflammation capacity, could mitigate inflammatory response and organ dysfunction in the lungs and liver induced by hemorrhagic shock/resuscitation (HS) plus abdominal compartment syndrome (ACS).

MATERIALS AND METHODS

Adult male rats were randomized to receive HS plus ACS or HS plus ACS plus minocycline (denoted as the HS/A and HS/A-M group, respectively; n = 12). Sham-instrumentation groups were employed to serve as the controls. Hemorrhagic shock/resuscitation was induced by blood drawing (mean arterial pressure: 40-45 mm Hg for 60 min) followed by shed blood/saline mixture reinfusion. Subsequently, intra-abdominal pressure (IAP) was increased to 25 mm Hg by injecting air into the preplaced intraperitoneal latex balloon to induce ACS. Minocycline (20 mg/kg) was intravenously administered immediately after resuscitation. IAP was maintained at 25 mm Hg for 6 h. Then, all rats were euthanized.

RESULTS

The levels of polymorphonuclear leukocyte infiltration, the wet/dry weight ratio, and the concentrations of inflammatory molecules (e.g., chemokine, cytokine, and prostaglandin E2) in lung and liver tissues of the HS/A group were significantly higher than those of the HS/A-M groups (all P < 0.05). Moreover, the levels of lung dysfunction (assayed by arterial blood gas) and liver dysfunction (assayed by plasma concentrations of bilirubin, aspartate aminotransferase, and alaninine aminotransferase) of the HS/A group were significantly higher than those of the HS/A-M group (all P < 0.05).

CONCLUSIONS

Minocycline ameliorates inflammatory response and organ dysfunction in the lungs and liver induced by hemorrhagic shock/resuscitation plus abdominal compartment syndrome.

Melanocortins as potential therapeutic agents in severe hypoxic conditions

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

Mechanisms of the beneficial effect of NHE1 inhibitor in traumatic hemorrhage: inhibition of inflammatory pathways

This study evaluated the effects of sodium-hydrogen exchanger (NHE1) inhibition on enhancing fluid resuscitation outcomes in traumatic hemorrhagic shock, and examined the mechanisms related to NHE1 inhibitor-induced protection and recovery from hemorrhagic shock. Traumatic hemorrhage was modeled in anesthetized pigs by producing tibia fractures followed by hemorrhage of 25 ml/kg for 20 min, and then a 4mm hepatic arterial tear with surgical repair after 20 min. Animals then underwent low volume fluid resuscitation with either hextend (n=6) or 3mg/kg BIIB513 (NHE1 inhibitor)+hextend (n=6). The experiment was terminated 6h after the beginning of resuscitation. In association with traumatic hemorrhagic shock, there was a decrease in cardiac index, stimulation of the inflammatory response, myocardial, liver and kidney injury. The administration of the NHE1 inhibitor at the time of resuscitation attenuated shock-resuscitation-induced myocardial hypercontracture and resulted in a significant increase in stroke volume index, compared to vehicle-treated controls. NHE1 inhibition also reduced the inflammatory response, and lessened myocardial, liver and kidney injury. In addition, NHE1 inhibition reduced NF-κB activation and iNOS expression, and attenuated of ERK1/2 phosphorylation. Results from the present study indicate that NHE1 inhibition prevents multiple organ injury by attenuating shock-resuscitation-induced myocardial hypercontracture and by inhibiting NF-κB activation and neutrophil infiltration, reducing iNOS expression and ERK1/2 phosphorylation, thereby, reducing systemic inflammation and thus multi-organ injury.

Balanced vs unbalanced crystalloid resuscitation in a near-fatal model of hemorrhagic shock and the effects on renal oxygenation, oxidative stress, and inflammation

BACKGROUND

The aim of the present study was to test the hypothesis that balanced crystalloid resuscitation would be better for the kidney than unbalanced crystalloid resuscitation in a rat hemorrhagic shock model.

METHODS

Male Wistar rats were randomly assigned to four groups (n=6/group): (1) time control; (2) hemorrhagic shock control; (3) hemorrhagic shock followed by unbalanced crystalloid resuscitation (0.9% NaCl); and (4) hemorrhagic shock followed by acetate and gluconate-balanced crystalloid resuscitation (Plasma Lyte). We tested the solutions for their effects on renal hemodynamics and microvascular oxygenation, strong-ion difference, systemic and renal markers of inflammation and oxidative stress including glycocalyx degradation as well as their effects on renal function.

RESULTS

The main findings of our study were that: (1) both the balanced and unbalanced crystalloid solutions successfully restored the blood pressure, but renal blood flow was only recovered by the balanced solution although this did not lead to improved renal microvascular oxygenation; (2) while unbalanced crystalloid resuscitation induced hyperchloremia and worsened metabolic acidosis in hemorrhaged rats, balanced crystalloid resuscitation prevented hyperchloremia, restored the acid-base balance, and preserved the anion gap and strong ion difference in these animals; (3) in addition balanced crystalloid resuscitation significantly improved renal oxygen consumption (increased VO(2), decreased [Formula: see text] ); and (4) however neither balanced nor unbalanced crystalloid resuscitation could normalize systemic inflammation or oxidative stress. Functional immunohistochemistry biomarkers showed improvement in L-FABP in favor of balanced solutions in comparison to the hemorrhagic group although no such benefit was seen for renal tubular injury (measured by NGAL) by giving either unbalanced or balanced solutions.

CONCLUSIONS

Although balanced crystalloid resuscitation seems superior to balanced crystalloid resuscitation in protecting the kidney after hemorrhagic shock and is certainly better than not applying fluid resuscitation, these solutions were not able to correct systemic inflammation or oxidative stress associated with hemorrhagic shock.

Posttreatment but not pretreatment with selective beta-adrenoreceptor 1 antagonists provides neuroprotection in the hippocampus in rats subjected to transient forebrain ischemia

BACKGROUND

beta-Adrenoreceptor antagonists provide neuroprotection against focal cerebral ischemia, but the effects of these antagonists on experimental global cerebral ischemia are unknown. That is, the effect of beta-adrenoreceptor antagonism in vulnerable brain regions after ischemic insult has not been examined. Therefore, we investigated the neuroprotective effects of preischemic or postischemic administration of propranolol (a nonselective beta-adrenoreceptor antagonist), esmolol, and landiolol (selective beta-adrenoreceptor 1 antagonists) against forebrain ischemia in rats.

METHODS

IV administration of saline 10 microL . h(-1), propranolol 100 microg . kg(-1) . min(-1), esmolol 200 microg . kg(-1) . min(-1), or landiolol 50 microg . kg(-1) . min(-1) in male Sprague-Dawley rats was started 30 minutes before or 60 minutes after 8-minute bilateral carotid artery occlusion combined with hypotension (35 mm Hg) under isoflurane (1.5%) anesthesia. All drugs were administered continuously until 5 days after reperfusion, and the animals were evaluated neurologically and histologically after this 5-day period.

RESULTS

Preischemic treatment with propranolol, esmolol, or landiolol failed to provide neuroprotection against forebrain ischemia in the hippocampus. Rats treated with propranolol tended to have a worse score for motor activity and a higher mortality rate (up to 64%), but the differences with other groups were not statistically significant. Postischemic treatment with esmolol and landiolol, but not with propranolol, reduced neuronal injury after forebrain ischemia. However, motor activity did not differ among rats treated postischemically with any of the beta-adrenoreceptor antagonists or saline.

CONCLUSIONS

Postischemic treatment with esmolol and landiolol provided neuroprotection in the hippocampus in rats subjected to bilateral carotid artery occlusion combined with hemorrhagic shock, whereas treatment with propranolol failed to show neuroprotection. We suggest that concomitant beta-blockade and shock might work as a systemic depressant, rather than a neuroprotectant, resulting in exacerbation of cerebral ischemia.

Sympathetic modulation of the host defense response to infectious challenge during recovery from hemorrhage

BACKGROUND

Trauma/hemorrhage (TxHem) is associated with an immediate pro-inflammatory response that, if exaggerated or prolonged, is thought to contribute to the subsequent immunosuppression that characterizes the period after injury. Previously we have demonstrated that chemical sympathectomy (SNSx) accentuates this immediate pro-inflammatory response to TxHem. These findings suggest that the noradrenergic system plays a critical role in limiting the magnitude of the inflammatory response during TxHem and preserving the integrity of the host defense response to a subsequent infectious challenge during the period after TxHem.

OBJECTIVE

To examine the contribution of tissue norepinephrine to the host defense response to an infectious challenge during recovery from TxHem.

METHODS

Male Sprague-Dawley rats underwent SNSx (6-hydroxydopamine, i.p. daily for 3 days) prior to vascular catheter implantation. Conscious, unrestrained rats were subjected to traumatic injury (muscle crush) prior to a fixed-pressure hemorrhage (40 mm Hg for 60 min) and fluid resuscitation followed 24 h later by cecal ligation and puncture (CLP).

RESULTS

SNSx impaired the hemodynamic and thermoregulatory response to hemorrhage as indicated by decreased basal blood pressure, impaired blood pressure recovery during fluid resuscitation, and greater hypothermia after CLP. Furthermore, SNSx accentuated the TNF-alpha, IL-1, IL-6, and IL-10 response to TxHem + infection in plasma 6 h after CLP and in peritoneal lavage fluid 24 h after CLP.

CONCLUSION

These results indicate that the integrity of the noradrenergic system is necessary for adequate hemodynamic, thermoregulatory, and inflammatory responses to infection during the period following TxHem.

Effect of biliary tract external drainage on cytokine expression and histomorphology of intestine, liver, and lung in rats with hemorrhagic shock

OBJECTIVE

To investigate the protective effect of biliary tract external drainage on cytokine expression and pathomorphism of intestine, liver, and lung in rats with hemorrhagic shock.

DESIGN

Randomized, control animal study.

SETTING

This study was conducted at The Institution Digestive Surgery Research Laboratory of Shanghai Jiao Tong University.

SUBJECTS

Sprague-Dawley rats.

INTERVENTIONS

Biliary tract external drainage was performed by inserting a cannula into the bile duct. Hemorrhagic shock was induced by drawing blood from the carotid artery.

MEASUREMENTS AND MAIN RESULTS

Twenty-four Sprague-Dawley rats were randomized to three equal groups of eight: sham shock; hemorrhagic shock; and hemorrhagic shock plus bile duct drainage. The messenger RNA expression of tumor necrosis factor-alpha, interleukin-6 in the intestine, liver, and lung tissue from the three groups were analyzed by reverse transcription-polymerase chain reaction. Tumor necrosis factor-alpha was analyzed in the bile of the rats by enzyme-linked immunosorbent assay. Histology of intestine, liver, and lung was performed in all groups by hematoxylin and eosin staining. The messenger RNA expression of tumor necrosis factor-alpha was significantly increased in the hemorrhagic shock group compared with the sham shock group (intestine 0.54 +/- 0.07 vs. 0.37 +/- 0.05, liver 1.01 +/- 0.06 vs. 0.56 +/- 0.07, lung 0.94 +/- 0.07 vs. 0.62 +/- 0.06). The messenger RNA expression of interleukin-6 was also significantly increased in the hemorrhagic shock group compared with the sham shock group (intestine 0.89 +/- 0.12 vs. 0.50 +/- 0.09, liver 1.07 +/- 0.10 vs. 0.57 +/- 0.12, lung 1.09 +/- 0.09 vs. 0.67 +/- 0.06). Biliary tract external drainage reduced significantly the messenger RNA expression of tumor necrosis factor-alpha (intestine 0.43 +/- 0.06 vs. 0.54 +/- 0.07, liver 0.74 +/- 0.18 vs. 1.01 +/- 0.06, lung 0.87 +/- 0.15 vs. 0.94 +/- 0.07) and interleukin-6 (intestine 0.60 +/- 0.11 vs. 0.89 +/- 0.12, liver 0.71 +/- 0.16 vs. 1.07 +/- 0.10, lung 0.88 +/- 0.25 vs. 1.09 +/- 0.09). The concentration of tumor necrosis factor-alpha in bile was significantly higher in the hemorrhagic shock group compared with the sham shock group (31.22 +/- 6.44 ng/mL vs. 15.49 +/- 3.64 ng/mL, p < .01). The histologic observation of the intestine, liver, and lung showed that the biliary tract external drainage significantly attenuate the putrescence and exfoliation of intestinal villi, denaturation and putrescence of hepatocytes, edema, and inflammatory cells infiltration of lung.

CONCLUSIONS

Biliary tract external drainage decreases the messenger RNA expression of tumor necrosis factor-alpha, interleukin-6 and attenuate the tissue injury of the intestine, liver, and lung in rats model of hemorrhagic shock. The gut-liver axis was implicated to play a crucial role in hemorrhagic shock-induced multiple organ dysfunction syndrome.

Bbeta15-42 (FX06) reduces pulmonary, myocardial, liver, and small intestine damage in a pig model of hemorrhagic shock and reperfusion

OBJECTIVE

The fibrin-derived peptide Bbeta15-42 (also called FX06) has been shown to reduce myocardial infarct size following ischemia/reperfusion. Hemorrhagic shock (HS) followed by volume resuscitation represents a similar scenario, whereby a whole organism is vulnerable to reperfusion injury.

DESIGN

We subjected male farm-bred landrace pigs ( approximately 30 kg) to HS by withdrawing blood to a mean arterial pressure of 40 mm Hg for 60 minutes. Pigs were then resuscitated with shed blood and crystalloids for 60 minutes, and at this time, FX06 (2.4 mg/kg, n = 8) or vehicle control (phosphate buffered saline; 2.4 mg/kg, n = 7) was injected as an intravenous bolus.

SETTING

University hospital laboratory.

SUBJECTS

Anesthetized male farm-bred landrace pigs.

MEASUREMENTS AND MAIN RESULTS

Data are presented as mean +/- sd. Five hours after resuscitation, controls presented acute lung injury (Pao2/Fio2-ratio <300 mm Hg; extra-vascular lung water index (marker for lung injury): 9.0 +/- 1.8 mL/kg) and myocardial dysfunction/damage (cardiac index: 4.3 +/- 0.25 L/min/m; stroke volume index: 30 +/- 6 mL/m; cardiac TnT levels: 0.58 +/- 0.25 ng/mL). In contrast, FX06-treated animals showed significantly improved pulmonary and circulatory function (Pao2/Fio2-ratio >*400 mm Hg; extra-vascular lung water index: *5.2 +/- 2.1 mL/kg, cardiac index: *6.3 +/- 1.4 L/min/m; stroke volume index: *51 +/- 11 mL/m; cardiac TnT levels: *0.11 +/- 0.09 ng/mL; *p < 0.05). Also, tissue oxygenation (tpO2; mm Hg) was significantly improved during reperfusion in FX06-treated pigs when compared with controls (liver 51 +/- 4 vs. *65 +/- 4; serosa 44 +/- 5 vs. *55 +/- 7; mucosa 14 +/- 4 vs. *26 +/- 4). Finally, FX06 reduced accumulation of myeloperoxidase-positive cells (mainly neutrophils) in myocardium, liver, and small intestine and reduced interleukin-6 plasma levels (*p < 0.05; compared with controls).

CONCLUSION

We conclude that in a pig model of HS and reperfusion, administration of FX06 during reperfusion protects shock- susceptible organs such as heart, lung, liver, and small intestine.

Effect of beta blockers (metoprolol or propranolol) on effect of simvastatin in lowering C-reactive protein in acute myocardial infarction

Recent data indicated that statin therapy may fail to reduce the incidence of coronary events in patients concomitantly using beta blockers. The aim of the present study was to examine whether the concomitant use of beta blockers would modify the anti-inflammatory action of statins. Changes in C-reactive protein (CRP) between days 1 and 5 after myocardial infarction were evaluated in 189 patients treated with simvastatin alone (S), beta blockers alone (B; propranolol or metoprolol), S + B, or neither of these 2 medications (N) in a prospective observational cohort. At baseline, median CRP was lower in the S group (0.40 mg/dl, interquartile range 0.1 to 0.6) than the other groups (B: 0.6 mg/dl, interquartile range 0.4 to 1.6; S + B: 0.5 mg/dl, interquartile range 0.3 to 1.2; and N: 0.6 mg/dl, interquartile range 0.2 to 1.5). By day 5, median CRP was 1.3 mg/dl (interquartile range 0.7 to 2.6), 4.3 (interquartile range 1.6 to 8.8), 4.6 (interquartile range 2.8 to 9.5), and 4.4 (interquartile range 1.9 to 9.9) for the S, B, S + B, and N groups, respectively. After adjusting for log(e) baseline CRP, the difference in log(e) CRP between days 1 and 5 was significantly lower in the S group compared with the B (-0.74 +/- 0.23 [SE], p = 0.001) or S + B group (-0.99 +/- 0.20 [SE], p <0.0001). The significance remained after adjustment for age, gender, and baseline CRP. There was no significant difference in change in CRP between the SB and B groups. In conclusion, the present study confirmed the anti-inflammatory action of statins and showed that concomitant use of beta blockers may significantly attenuate this effect.

The importance of immune dysfunction in determining outcome in acute liver failure

Acute liver failure (ALF) shares striking similarities with septic shock with regard to the features of systemic inflammation, progression to multiple organ dysfunction and functional immunoparesis. While the existence of opposing systemic pro- and anti-inflammatory profiles resulting in organ failure and immune dysfunction are well recognised in septic shock, characterization of these processes in ALF has only recently been described. This review explores the evolution of the systemic inflammation in acute liver failure, its relation to disease progression, exacerbation of liver injury and development of innate immune dysfunction and extra-hepatic organ failure as sequelae. Defects in innate immunity are described in hepatic and extra-hepatic compartments. Clinical studies measuring levels of pro- and anti-inflammatory cytokines and expression of the antigen presentation molecule HLA-DR on monocytes, in combination with ex-vivo experiments, demonstrate that the persistence of a compensatory anti-inflammatory response syndrome, leading to functional monocyte deactivation, is a central event in the evolution of systemic immune dysfunction. Accurate immune profiling in ALF may permit the development of immunomodulatory strategies in order to improve outcome in this condition.

Prolonged fever following kidney biopsy: a case report

This case report describes a patient with prolonged fever following a kidney biopsy. Workup disclosed a large perirenal and retroperitoneal hematoma. Neither imaging nor blood cultures supported an infective cause of his fever. Although the patient was initially treated with antibiotics, fever eventually resolved spontaneously. A review of the literature is provided addressing the association of fever with resorption of hematoma. Fever should be added to the list of potential complications of kidney biopsy. A conservative management is advocated.

Bleeding and outcome in acute coronary syndrome: insights from continuous electrocardiogram monitoring in the Integrilin and Enoxaparin Randomized Assessment of Acute Coronary Syndrome Treatment (INTERACT) Trial

BACKGROUND

Bleeding is associated with adverse outcome in acute coronary syndromes. However, the precise pathophysiologic mechanisms have not been elucidated. We sought to determine the relationship between bleeding and myocardial ischemia detected by concurrent continuous electrocardiogram (ECG) monitoring and their independent long-term prognostic significance.

METHODS

The INTERACT trial was a randomized controlled trial of enoxaparin versus unfractionated heparin in patients with high-risk non-ST-elevation acute coronary syndromes. Continuous ECG monitoring, performed after enrollment up to 96 hours, was analyzed by an automated algorithm and reviewed by a blinded cardiologist. We centrally adjudicated all bleeding and clinical events in a blinded fashion and calculated the Global Registry of Acute Coronary Events risk score (a validated predictor of mortality) for each patient.

RESULTS

Of the 746 patients enrolled, 34 (4.6%) developed major bleeding within 96 hours. After a median follow-up of 2.4 years, patients with bleeding had a higher risk of death (28.4% vs 7.3%, P < .001) and death/myocardial infarction (38.0% vs 12.9%, P < .001) compared with those without bleeding. Overall, 619 patients survived the first 96 hours with complete data on continuous ECG monitoring. Bleeding was associated with the simultaneous presence of ST-segment shifts on continuous ECG monitoring (P = .03). After adjusting for Global Registry of Acute Coronary Events risk score and myocardial ischemia detected by continuous ECG monitoring, major bleeding remained an independent predictor of death (adjusted hazard ratio = 3.48, 95% confidence interval 1.51-8.03, P = .003) and death/myocardial infarction (adjusted hazard ratio = 2.85, 95% confidence interval 1.40-5.78, P = .004).

CONCLUSIONS

Bleeding is a powerful independent predictor of poor long-term outcome, even after adjusting for other associated prognostic factors such as advanced age and renal dysfunction. Although bleeding is associated with concurrent myocardial ischemia, its adverse prognostic impact may be mediated by complex pathophysiologic mechanisms rather than myocardial ischemia alone. Our findings suggest that future investigations should focus on other biologically plausible mechanisms.