Discovery of novel biaryl benzoxazepinones as dual-mode receptor-interacting protein kinase-1 (RIPK1) inhibitors

Systemic inflammatory response syndrome (SIRS), an exaggerated defense response of the organism to a noxious stressor, involves a massive inflammatory cascade that ultimately leads to reversible or irreversible end-organ dysfunction and even death. Suppressing RIPK1, a key protein in necroptosis pathway, has been proven to be an effective therapeutic strategy for inflammation and SIRS. In this study, a series of novel biaryl benzoxazepinone RIPK1 inhibitors were designed and synthesized by introducing different aryl substituents at the C7 position of benzoxazepinone. As a result, p-cyanophenyl substituted analog 19 exhibited the most potent in vitro anti-necroptotic effect in HT-29 cells (EC50 = 1.7 nM) and superior protection against temperature loss and death in mice in the TZ-induced SIRS model compared to GSK'772. What's more, in vivo analysis of the levels of inflammatory factors in mice also revealed that compound 19 had better anti-inflammatory activity than GSK'772.

[Systemic inflammatory response syndrome associated with use of ticagrelor]

Ticagrelor is anantiplatelet agent which acts through reversible binding to the P2Y12 adenosine-diphosphate receptors. In acute coronary syndromes it has been shown to reduce the risk of major cardiovascular events such as myocardial infarction, stroke and death. Although some hemorrhagic, kidney, liver and respiratory complications have been described in detail with the use of ticagrelor, other less frequent adverse effects are not so well clarified. We report the case of a patient with a systemic inflammatory response syndrome secondary to the use of ticagrelor.

TDP-43 mediated blood-brain barrier permeability and leukocyte infiltration promote neurodegeneration in a low-grade systemic inflammation mouse model

BACKGROUND

Neuronal cytoplasmic inclusions containing TAR DNA-binding protein 43 (TDP-43) are a neuropathological feature of several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer's Disease (AD). Emerging evidence also indicates that systemic inflammation may be a contributor to the pathology progression of these neurodegenerative diseases.

METHODS

To investigate the role of systemic inflammation in the progression of neuronal TDP-43 pathology, AAV9 particles driven by the UCHL1 promoter were delivered to the frontal cortex of wild-type aged mice via intracranial injections to overexpress TDP-43 or green fluorescent protein (GFP) in corticospinal motor neurons. Animals were then subjected to a low-dose (500 μg/kg) intraperitoneal E. coli lipopolysaccharide (LPS) administration challenge for 2 weeks to mimic a chronically altered low-grade systemic inflammatory state. Mice were then subjected to neurobehavioral studies, followed by biochemical and immunohistochemical analyses of the brain tissue.

RESULTS

In the present study, we report that elevated neuronal TDP-43 levels induced microglial and astrocytic activation in the cortex of injected mice followed by increased RANTES signaling. Moreover, overexpression of TDP-43 exerted abundant mouse immunoglobulin G (IgG), CD3, and CD4+ T cell infiltration as well as endothelial and pericyte activation suggesting increased blood-brain barrier permeability. The BBB permeability in TDP-43 overexpressing brains yielded the frontal cortex vulnerable to the systemic inflammatory response following LPS treatment, leading to marked neutrophil infiltration, neuronal loss, reduced synaptosome-associated protein 25 (SNAP-25) levels, and behavioral impairments in the radial arm water maze (RAWM) task.

CONCLUSIONS

These results reveal a novel role for TDP-43 in BBB permeability and leukocyte recruitment, indicating complex intermolecular interactions between an altered systemic inflammatory state and pathologically prone TDP-43 protein to promote disease progression.

Squalene-based multidrug nanoparticles for improved mitigation of uncontrolled inflammation in rodents

Uncontrolled inflammatory processes are at the root of numerous pathologies. Most recently, studies on confirmed COVID-19 cases have suggested that mortality might be due to virally induced hyperinflammation. Uncontrolled pro-inflammatory states are often driven by continuous positive feedback loops between pro-inflammatory signaling and oxidative stress, which cannot be resolved in a targeted manner. Here, we report on the development of multidrug nanoparticles for the mitigation of uncontrolled inflammation. The nanoparticles are made by conjugating squalene, a natural lipid, to adenosine, an endogenous immunomodulator, and then encapsulating α-tocopherol, as antioxidant. This resulted in high drug loading, biocompatible, multidrug nanoparticles. By exploiting the endothelial dysfunction at sites of acute inflammation, these multidrug nanoparticles delivered the therapeutic agents in a targeted manner, conferring survival advantage to treated animals in models of endotoxemia. Selectively delivering adenosine and antioxidants together could serve as a novel therapeutic approach for safe treatment of acute paradoxal inflammation.

Evaluation of systemic inflammatory response and lung injury induced by Crotalus durissus cascavella venom

This study investigated the systemic inflammatory response and mechanism of pulmonary lesions induced by Crotalus durissus cascavella venom in murine in the state of Bahia. In order to investigate T helper Th1, Th2 and Th17 lymphocyte profiles, we measured interleukin (IL) -2, IL-4, IL-6, IL-10, IL-17, tumor necrosis factor (TNF) and interferon gamma (IFN-γ) levels in the peritoneal fluid and macerated lungs of mice and histopathological alterations at the specific time windows of 1h, 3h, 6h, 12h, 24h and 48h after inoculation with Crotalus durissus cascavella venom. The data demonstrated an increase of acute-phase cytokines (IL-6 and TNF) in the first hours after inoculation, with a subsequent increase in IL-10 and IL-4, suggesting immune response modulation for the Th2 profile. The histopathological analysis showed significant morphological alterations, compatible with acute pulmonary lesions, with polymorphonuclear leukocyte (PMN) infiltration, intra-alveolar edema, congestion, hemorrhage and atelectasis. These findings advance our understanding of the dynamics of envenomation and contribute to improve clinical management and antiophidic therapy for individuals exposed to venom.

Exposure to Atmospheric Ultrafine Particles Induces Severe Lung Inflammatory Response and Tissue Remodeling in Mice

Exposure to particulate matter (PM) is leading to various respiratory health outcomes. Compared to coarse and fine particles, less is known about the effects of chronic exposure to ultrafine particles, despite their higher number and reactivity. In the present study, we performed a time-course experiment in mice to better analyze the lung impact of atmospheric ultrafine particles, with regard to the effects induced by fine particles collected on the same site. Trace element and PAH analysis demonstrated the almost similar chemical composition of both particle fractions. Mice were exposed intranasally to FF or UFP according to acute (10, 50 or 100 µg of PM) and repeated (10 µg of PM 3 times a week during 1 or 3 months) exposure protocols. More particle-laden macrophages and even greater chronic inflammation were observed in the UFP-exposed mice lungs. Histological analyses revealed that about 50% of lung tissues were damaged in mice exposed to UFP for three months versus only 35% in FF-exposed mice. These injuries were characterized by alveolar wall thickening, macrophage infiltrations, and cystic lesions. Taken together, these results strongly motivate the update of current regulations regarding ambient PM concentrations to include UFP and limit their emission.

Trait-specific effects of exogenous triiodothyronine on cytokine and behavioral responses to simulated systemic infection in male Siberian hamsters

Seasonal changes in day length enhance and suppress immune function in a trait-specific manner. In Siberian hamsters (Phodopus sungorus) winter-like short days (SDs) increase blood leukocyte concentrations and adaptive T cell dependent immune responses, but attenuate innate inflammatory responses to simulated infections. Thyroid hormone (TH) signaling also changes seasonally and has been implicated in modulation of the reproductive axis by day length. Immunologically, TH administration in long days (LD) enhances adaptive immune responses in male Siberian hamsters, mimicking effects of SDs. This experiment tested the hypothesis that T₃ is also sufficient to mimic the effects of SD on innate immune responses. Adult male hamsters housed in LDs were pretreated with triiodothyronine (T₃; 1 μg, s.c.) or saline (VEH) daily for 6 weeks; additional positive controls were housed in SD and received VEH, after which cytokine, behavioral, and physiological responses to simulated bacterial infection (lipopolysaccharide; LPS) were evaluated. SD pretreatment inhibited proinflammatory cytokine mRNA expression (i.e. interleukin 1β, nuclear factor kappa-light-chain-enhancer of activated B cells). In addition, the magnitude and persistence of anorexic and cachectic responses to LPS were also lower in SD hamsters, and LPS-induced inhibition of nest building behavior was absent in SD. T₃ treatments failed to affect behavioral (food intake, nest building) or somatic (body mass) responses to LPS in LD hamsters, but one CNS cytokine response to LPS (e.g., hypothalamic TNFα) was augmented by T₃. Together these data implicate thyroid hormone signaling in select aspects of innate immune responses to seasonal changes in day length.

Recovery from an acute systemic and central LPS-inflammation challenge is affected by mouse sex and genetic background

Genetic and sexual factors influence the prevalence and the pathogenesis of many inflammatory disorders. In this study their relevance on the peripheral and central inflammatory status induced by a peripheral injection of lipopolysaccharide (LPS) was evaluated. BALB/c and CD-1 male and female mice were intraperitoneally injected with LPS. Spleens and brains were collected 2 and 72 hours later to study the levels of IL-6, TNF-α and IL-1β. Percentage of microglia and astrocytes was determined in the cortex and hippocampus. Locomotor activity was registered before and during the 72 hours after LPS-treatment. Two hours after LPS-injection, a peripheral increase of the three cytokines was found. In brains, LPS increased TNF-α only in males with higher levels in CD-1 than BALB/c. IL-1β increased only in CD-1 males. IL-6 increased in both strains with lower levels in BALB/c females. Peripheral and central levels of cytokines decline 72 hrs after LPS-treatment whilst a significantly increase of Iba-1 expression was detected. A dramatic drop of the locomotor activity was observed immediately after LPS injection. Our results show that acute systemic administration of LPS leads to peripheral and central increase of pro-inflammatory cytokines and microglia activation, in a strain and sex dependent manner.

Ticagrelor induced systemic inflammatory response syndrome

BACKGROUND

Ticagrelor is a reversible and direct-acting oral antagonist of the adenosine diphosphate receptor P2Y12. Possible adenosine-mediated effects of ticagrelor on inflammation are complex and incompletely understood. To our knowledge, ticagrelor-induced systemic inflammatory response syndrome (SIRS) has not yet been described.

CASE PRESENTATION

We report the case of an 84 years old patient presenting with SIRS subsequent to initiation of ticagrelor after implantation of two drug eluting stents. A broad diagnostic work-up for alternative causes and therapeutic measures were unrevealing. Discontinuation of the agent was followed by rapid improvement in clinical and laboratory signs of SIRS.

CONCLUSIONS

After exclusion of other causes, ticagrelor needs to be considered as a possible causative agent for SIRS. Due to the widespread use of ticagrelor, clinicians should be aware of this possible adverse drug reaction.

[Not Available]

Zusammenfassung. Wir präsentieren den Fall eines aufgrund einer rheumatoiden Arthritis mit Azathioprin und Prednison immunsupprimierten 66-jährigen Mannes, der wegen Fieber, Schüttelfrost, Dyspnoe und Myalgien hospitalisiert wurde. Es waren alle Kriterien eines SIRS erfüllt bei jedoch weder laborchemisch noch bildgebend (inkl. Echokardiografie) nachweisbarem Entzündungs- oder Infektfokus. Obwohl es unter empirischer antibiotischer Therapie zu einer raschen Symptomregredienz kam, trat nach Wiederbeginn mit Azathioprin die gleiche Symptomatik wie bei Eintritt auf. Dies führte uns zur Diagnose einer Hypersensitivitätsreaktion auf Azathioprin mit SIRS.

Severe non-infective systemic inflammatory response syndrome, shock, and end-organ dysfunction after zoledronic acid administration in a child

INTRODUCTION

Zoledronic acid is an intravenous bisphosphonate used to increase bone mineral density and reduce the risk of fractures. Its safety profile compares well with pamidronate in pediatric patients. We describe an acute, severe, life-threatening, inflammatory reaction in a child.

METHODS

A 7-year-old boy with complex medical problems and chronic ventilator requirements was admitted to the pediatric intensive care unit (due to ventilator needs) for zoledronic acid infusion and subsequent monitoring. His history was significant for osteoporosis secondary to immobilization with multiple fractures since 2 years of age, hypoxic-ischemic encephalopathy, quadriplegic cerebral palsy, seizure disorder, ventilator dependence, and pulmonary hypertension. He had previously been treated with four cycles of pamidronate without adverse events. He received 0.013 mg/kg of zoledronic acid infused over 30 minutes. Beginning 3 hours after completion of the infusion, he developed progressive tachycardia, fever, hypotension requiring vasopressor infusion, and increasing oxygen requirements. Laboratory studies revealed leukopenia, thrombocytopenia, elevated C-reactive protein, abnormal coagulation profile, metabolic acidosis, and negative cultures. The following day, he developed moderate acute respiratory distress syndrome and pulmonary hemorrhage requiring higher ventilatory settings, and subsequently diarrhea and abdominal distension. Initial clinical resolution was noted from the third day onward, and he was discharged on the sixth day after zoledronate administration.

RESULTS

Our pediatric patient demonstrated an acute, severe, life-threatening reaction to zoledronic acid requiring intensive cardiorespiratory support without an underlying pre-existing inflammatory disorder.

CONCLUSION

Our case highlights the importance of careful monitoring of children following zoledronic acid therapy. We recommend inpatient observation after an initial infusion of zoledronic acid in medically complex children. Children and their parents should be thoroughly counseled on the potential risks of bisphosphonate treatment, which can sometimes be severe and life threatening.

Dimethyl sulfoxide inhibits zymosan-induced intestinal inflammation and barrier dysfunction

AIM: To investigate whether dimethyl sulfoxide (DMSO) inhibits gut inflammation and barrier dysfunction following zymosan-induced systemic inflammatory response syndrome and multiple organ dysfunction syndrome.

METHODS: Sprague-Dawley rats were randomly divided into four groups: sham with administration of normal saline (SS group); sham with administration of DMSO (SD group); zymosan with administration of normal saline (ZS group); and zymosan with administration of DMSO (ZD group). Each group contained three subgroups according to 4 h, 8 h, and 24 h after surgery. At 4 h, 8 h, and 24 h after intraperitoneal injection of zymosan (750 mg/kg), the levels of intestinal inflammatory cytokines [tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-10] and oxides (myeloperoxidase, malonaldehyde, and superoxide dismutase) were examined. The levels of diamine oxidase (DAO) in plasma and intestinal mucosal blood flow (IMBF) were determined. Intestinal injury was also evaluated using an intestinal histological score and apoptosis of intestinal epithelial cells was determined by deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The intestinal epithelial tight junction protein, ZO-1, was observed by immunofluorescence.

RESULTS: DMSO decreased TNF-α and increased IL-10 levels in the intestine compared with the ZS group at the corresponding time points. The activity of intestinal myeloperoxidase in the ZS group was higher than that in the ZD group 24 h after zymosan administration (P < 0.05). DMSO decreased the content of malondialdehyde (MDA) and increased the activity of superoxide dehydrogenase (SOD) 24 h after zymosan administration. The IMBF was lowest at 24 h and was 49.34% and 58.26% in the ZS group and ZD group, respectively (P < 0.05). DMSO alleviated injury in intestinal villi, and the gut injury score was significantly lower than the ZS group (3.6 ± 0.2 vs 4.2 ± 0.3, P < 0.05). DMSO decreased the level of DAO in plasma compared with the ZS group (65.1 ± 4.7 U/L vs 81.1 ± 5.0 U/L, P < 0.05). DMSO significantly preserved ZO-1 protein expression and localization 24 h after zymosan administration. The TUNEL analysis indicated that the number of apoptotic intestinal cells in the ZS group was much higher than the ZD group (P < 0.05).

CONCLUSION: DMSO inhibited intestinal cytokines and protected against zymosan-induced gut barrier dysfunction.

Protective effect of leaf essential oil from Cinnamomum osmophloeum Kanehira on endotoxin-induced intestinal injury in mice associated with suppressed local expression of molecules in the signaling pathways of TLR4 and NLRP3

Endotoxin is a potent microbial mediator implicated in sepsis. We investigated the anti-inflammatory effect of leaf essential oil from Cinnamomum osmophloeum Kanehira (CO) of the linalool chemotype on endotoxin-injected mice. Mice were administered CO or vehicle by gavage before endotoxin injection and were killed 12 h after injection. Neither growth nor the organ weight or tissue weight to body weight ratio was affected by CO treatment. CO significantly lowered peripheral levels of tumor necrosis factor-α, interleukin (IL)-1β, IL-18, interferon-γ, and nitric oxide and inhibited the expression of toll-like receptor 4 (TLR4), myeloid differentiation primary response gene (88), myeloid differentiation factor 2, apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC), caspase-1, and Nod-like receptor family, pyrin domain containing 3 (NLRP3). CO also inhibited the activation of nuclear factor-ĸB, inhibited the activity of caspase-1 in small intestine, and ameliorated intestinal edema. Our data provide strong evidence for a protective effect of CO of the linalool chemotype in the endotoxin-induced systemic inflammatory response in close association with suppression of the TLR4 and NLRP3 signaling pathways in intestine.

Toxicological Characteristics of Titanium Dioxide Nanoparticle in Rats

In an effort to examine liver, heart and kidney injury, immune response, and other physiological effect in rats caused by intratracheal instillation of nano titanium dioxide (TiO2) for 28 days, we assessed T lymphocytes counts, hematological indices, biochemical parameters, cytokines assay and histopathological changes in nano TiO2 treated rats. Indeed, rats treated with nano TiO2 displayed a reduction in body weight and coefficients of the hearts. Edema and loose cytoplasm on liver cells were found in nano groups. The results showed that a statistically significant increased in the BUN, HTC and AST levels than those in control group. Our data suggested that the immunologically competent cells of CD3+, CD4+, and CD8+ caused by nano TiO2 32 mg/kg group were significantly lower than control group. The ratio of CD4+ to CD8+ from the nano 32 mg/kg group was significantly increased and showed a disturbance of cellular immune function. But ELISA analysis showed that no significant changes in IFN-γ and IL-4 were observed throughout the experimental period in this study.

Bacopa monniera Stabilized Silver Nanoparticles Attenuates Oxidative Stress Induced by Aluminum in Albino Mice

In the recent years usage of nanomedicine plays a promising strategy in the improvement of medical treatment. The ecofriendly synthesized silver nanoparticles has introduced a new opportunity to increase the efficacy of drug by reducing its side effects. In the present study, we investigated the antioxidant property of Bacopa monniera stabilized silver nanoparticles against aluminum induced toxicity in albino mice. Forty male albino mice were randomly divided into five groups. First group was treated as control, second group received aluminum acetate (5 mg/kg b . w), third group received Bacopa monniera extract (5 mg/kg b . w), fourth group received BmSNPs (5 mg/kg b . w), fifth group received aluminum acetate plus BmSNPs. Exposure to aluminum acetate significantly increased lipid peroxidation levels with a significant decrease in the antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase activities in the brain, liver and kidney of mice. Degenerative changes were also observed in brain, liver and kidney of aluminum treated mice. No significant changes in the oxidative stress were observed in the Bacopa monniera and BmSNPs alone treated mice. Whereas, co-administration of BmSNPs to Al treated mice showed a significant decrease in lipid peroxidation levels with a significant increase of SOD, CAT and GPx indicating the antioxidant potential of nanoparticles and in counteracting Al induced oxidative stress and histological response in male albino mice. These findings clearly implicate that BmSNPs are able to eradicate the oxidative stress and prevent the tissue damage in aluminum exposed mice.

Absence of systemic toxicity in mouse model towards BaTiO3 nanoparticulate based eluate treatment

One of the existing issues in implant failure of orthopedic biomaterials is the toxicity induced by the fine particles released during long term use in vivo, leading to acute inflammatory response. In developing a new class of piezobiocomposite to mimic the integrated electrical and mechanical properties of bone, bone-mimicking physical properties as well as in vitro cytocompatibility properties have been achieved with spark plasma sintered hydroxyapatite (HA)-barium titanate (BaTiO3) composites. However, the presence of BaTiO3 remains a concern towards the potential toxicity effect. To address this issue, present work reports the first result to conclusively confirm the non-toxic effect of HA-BaTiO3 piezobiocomposite nanoparticulates, in vivo. Twenty BALB/c mice were intra-articularly injected at their right knee joints with different concentrations of HA-BaTiO3 composite of up to 25 mg/ml. The histopathological examination confirmed the absence of any trace of injected particles or any sign of inflammatory reaction in the vital organs, such as heart, spleen, kidney and liver at 7 days post-exposure period. Rather, the injected nanoparticulates were found to be agglomerated in the vicinity of the knee joint, surrounded by macrophages. Importantly, the absence of any systemic toxicity response in any of the vital organs in the treated mouse model, other than a mild local response at the site of delivery, was recorded. The serum biochemical analyses using proinflammatory cytokines (TNF-α and IL-1β) also complimented to the non-immunogenic response to injected particulates. Altogether, the absence of any inflammatory/adverse reaction will open up myriad of opportunities for BaTiO3 based piezoelectric implantable devices in biomedical applications.

Temporal gene expression in the hippocampus and peripheral organs to endotoxin-induced systemic inflammatory response in caspase-1-deficient mice

OBJECTIVES

Caspase-1 (casp1), a key protease involved in the systemic inflammatory response syndrome (SIRS), controls the brain expression of a set of eight genes: Nos2 and Ptgs2 (nitric oxide synthase 2 and prostaglandin-endoperoxide synthase 2, two inducible enzymes), Cxcl1 and Cxcl10 (C-X-C motif chemokine ligand 1 and ligand 10), Tgtp and Gbp2 (T cell-specific GTPase 1 and guanylate-binding protein 2, two GTPases), Adamts1 (a disintegrin-like and metallopeptidase with thrombospondin type 1 motif, 1, a metalloprotease) and Il1rn (interleukin-1 receptor antagonist). Our objective was to ascertain whether casp1 also controlled the peripheral expression of these genes and, if so, to compare their central versus peripheral patterns of gene expression in immune and endocrine tissues during SIRS.

METHODS

Wild-type (wt) and casp1 knockout (casp1(-/-)) mice were injected with either saline or a high dose of endotoxin/lipopolysaccharide (LPS; 800 μg/mice i.p.). Saline-injected mice were immediately euthanized after injection, whereas LPS-injected mice were sacrificed 6 and 12 h after LPS administration. Hippocampal, splenic and adrenal gene expressions were determined by real-time PCR.

RESULTS

Overall, casp1(-/-) mice showed a lower inflammatory response than wt mice. The expression levels of powerful proinflammatory factors such as Nos2 and Ptgs2 was reduced in casp1(-/-) mice. Moreover, a hierarchical clustering analysis aimed at studying patterns of gene coexpression revealed large alterations in the hippocampal pattern of casp1(-/-) mice. Surprisingly, the expression of Adamts1 was increased in the hippocampus and adrenals of casp1(-/-) mice.

CONCLUSIONS

The resilience of casp1(-/-) mice to SIRS lethality is associated with a lower inflammatory response, loss of hippocampal gene coexpression patterns, and increased hippocampal Adamts1 gene expression. The latter might be beneficial for casp1(-/-) mice, since ADAMTS1 is likely to play a role in neuronal plasticity. The mechanisms described here may help the development of either novel biomarkers or therapeutic targets against SIRS/sepsis.

FJU-C4, a new 2-pyridone compound, attenuates lipopolysaccharide-induced systemic inflammation via p38MAPK and NF-κB in mice

Despite advances in antibiotic therapy and intensive care, the mortality caused by systemic inflammatory response syndrome and severe sepsis remains high. The use of anti-inflammatory agents to attenuate inflammatory response during acute systemic inflammatory reactions may improve survival rates. Here we show that a newly synthesized 2-pyridone compound (FJU-C4) can suppress the expression of late inflammatory mediators such as iNOS and COX-2 in murine macrophages. The pro-inflammatory cytokines, including TNFα, IL-1β, and IL-6, were dose-dependently suppressed by FJU-C4 both in mRNA and protein levels. In addition, the expression of TNFα was inhibited from as early as 2 hours after exposure to LPS stimulation. The production of mature pro-inflammatory cytokines was also suppressed by pretreatment with FJU-C4 in either cell culture medium or mice serum when stimulated by LPS. FJU-C4 prolongs mouse survival and prevents mouse death from LPS-induced systemic inflammation when the dose of FJU-C4 is over 5 mg/kg. The activities of ERK, JNK, and p38MAPK were induced by LPS stimulation on murine macrophage cell line, but only p38MAPK signaling was dramatically suppressed by pretreatment with the FJU-C4 compound in a dose-dependent manner. NF-κB activation also was suppressed by FJU-C4 compound. These findings suggest that the FJU-C4 compound may act as a promising therapeutic agent against inflammatory diseases by inhibiting the p38MAPK and NF-κB signaling pathway.

Amelioration of Danhong injection on the lipopolysaccharide-stimulated systemic acute inflammatory reaction via multi-target strategy

ETHNOPHARMACOLOGICAL RELEVANCE

Systemic inflammatory response syndrome (SIRS), leading to dire consequences, is a serious and fatal disease in clinic. Danhong injection (DHI), one of the most popular medications for coronary heart disease and cerebral ischemia, plays pharmacological actions through inhibiting local inflammation. Nevertheless, the anti-inflammatory effect of DHI has not been reported before and has not been fully clarified.

AIM OF THE STUDY

In this study, a model of systemic acute inflammatory reaction was induced by lipopolysaccharide (LPS) to investigate whether DHI could be applied to SIRS through the anti-inflammatory effect.

MATERIAL AND METHODS

The anti-inflammatory effect of DHI in vivo was evaluated in ICR mice pretreated intraperitoneally (i.p.) with LPS (1mg/kg) and the serum, liver and kidney were collected. Interleukin (IL)-6, tumor necrosis factor (TNF)-α and monocyte chemotactic protein (MCP-1) in serum were measured by enzyme-linked immunosorbent assay (ELISA) and the mRNA expressions of inducible NO synthase (iNOS), IL-6, interleukin (IL)-1β, MCP-1 in mice liver and kidney were analyzed by quantitative real-time reverse-transcription polymerase chain reaction (real-time RT-PCR). Meanwhile, Proteome profiler array was used to screen the acute phase proteins, cytokines and chemokines activated in the acute inflammation. The inflammatory model of macrophages stimulated by LPS (0.2μg/mL) was used to evaluate the anti-inflammatory mechanism of DHI in vitro. The secretion of nitric oxide (NO) was measured by the Griess reagent system. The productions of prostaglandin E2 (PGE2), IL-6, TNF-α and MCP-1 were detected using ELISA, and the protein expression of cyclooxygenase (COX)-2 was determined by cell-based ELISA. As well, the mRNA expressions of these inflammatory factors were detected by real-time RT-PCR.

RESULTS

DHI could attenuate the inflammatory reaction via decreasing 20 cytokines and acute phase proteins analyzed by Proteome profile array in serum. The secretions of IL-6, TNF-α and MCP-1 in serum were coincidence with the result of Proteome profile array. Meanwhile, the mRNA expressions of iNOS, IL-6, IL-1β, MCP-1 in mice liver and kidney were significantly reduced by DHI. Experiments performed in vitro further revealed that the productions of NO, PGE2 and the mRNA expressions of iNOS, COX-2 were notably inhibited by DHI. Cell-based ELISA revealed that the COX-2 protein expression was diminished by DHI. The results of ELISA demonstrated that DHI significantly down-regulated the protein productions of IL-6 and MCP-1. Furthermore, the mRNA expressions of iNOS, COX-2, TNF-α, IL-1β, IL-6 and MCP-1 analyzed by real-time RT-PCR were suppressed by DHI.

CONCLUSIONS

These results demonstrate that DHI exerts the protective effect through inhibiting the expressions of iNOS, COX-2, IL-1β, IL-6, MCP-1 and TNF-α, which elucidate that DHI may be a strongly multi-target Chinese medicine injection on improving the inflammatory diseases.

Granulocyte colony stimulating factor induces lipopolysaccharide (LPS) sensitization via upregulation of LPS binding protein in rat

Liver is the main organ for lipopolysaccharide (LPS) clearance. Sensitization to LPS is associated with the upregulation of LPS-binding protein (LBP) in animal models. Therefore, we hypothesized that LBP could induce LPS sensitization through enhancing hepatic uptake of LPS. In this study, we examined the role of LBP in pathogenesis of LPS induced systemic inflammatory response syndrome (SIRS). LBP expression was upregulated after granulocyte colony stimulating (G-CSF) pretreatment. The effect of LBP was further confirmed by blockade of LBP using LBP blocking peptide--LBPK95A. After G-CSF pretreatment, upregulation of LBP was observed in bone marrow cells and liver. The G-CSF induced LBP upregulation caused LPS hypersensitization in rats as indicated by higher mortality and severer liver damage. Of note, LBP blockade increased the survival rate and attenuated the liver injury. The LBP induced LPS hypersensitization was associated with increased hepatic uptake of LPS and augmented hepatic expression of LPS receptors, such as toll-like receptor (TLR)-4. Furthermore, LBP mediated early neutrophil infiltration, which led to increased monocyte recruitment in liver after LPS administration. In conclusion, G-CSF induced LBP expression could serve as a new model for investigation of LPS sensitization. We demonstrated the crucial role of LBP upregulation in pathogenesis of LPS induced SIRS.

Postnatal systemic inflammation exacerbates impairment of hippocampal synaptic plasticity in an animal seizure model

OBJECTIVE

To investigate the effects of systemic inflammation in the critical postnatal stages on neurophysiological actions of immune processes and neural plasticity in adult rats after kainic acid (KA)-induced seizures.

METHODS

To determine changes in hippocampal synaptic plasticity after postnatal central nervous system inflammatory responses and seizure attacks, we performed intraperitoneal injections of lipopolysaccharide (LPS) in postnatal Sprague Dawley rats on day 14 (P14) to induce central nervous system inflammation. We then used a KA tail vein injection on P35 to induce seizure attacks. We compared the variability in synaptic plasticity in the hippocampal Schaffer collateral-CA1 region of seizure animals with or without LPS-induced inflammation preconditioning.

RESULTS

P14 injection of LPS increased susceptibility to seizures, while treatment with KA on P35 induced seizures. Long-term potentiation (LTP) of the Schaffer collateral-CA1 region was impaired in seizure animals, and this effect was more pronounced in the P14 LPS injection group. Fluoro-Jade staining revealed an increase in degenerated hippocampal CA1 pyramidal cells in the P14 LPS injection group. Cytokine expression in the hippocampus in the pre-, peri- and postictus periods was greater in P14 LPS rats than in saline-treated rats.

CONCLUSIONS

Intraperitoneal LPS injection on P14 induces higher cytokine secretion after KA-induced seizures, enhancing neuronal excitability, shortening seizure onset time and exacerbating neuronal degeneration and impairment of LTP formation in the hippocampal Schaffer collateral-CA1 region. Central nervous system inflammation during critical stages of childhood development could disrupt the balance needed for neurophysiological actions of immune processes, producing direct, pernicious effects on memory, neural plasticity and neurogenesis into adulthood.

Differences in the inflammatory response induced by acute pancreatitis in different white adipose tissue sites in the rat

BACKGROUND

There is increasing evidence of the role of adipose tissue on the systemic effects of acute pancreatitis. Patients with higher body mass index have increased risk of local and systemic complications and patients with android fat distribution and higher waist circumference are at greater risk for developing the severe form of the disease. Here we evaluated the changes on different areas of adipose tissue and its involvement on the inflammatory response in an experimental model of acute pancreatitis.

METHODS

Pancreatitis was induced in male Wistar rats by intraductal administration of sodium taurocholate. Orlistat was administered to inhibit lipase activity. Activation of peritoneal macrophages was evaluated by measuring IL1β and TNFα expression. Inflammation was evaluated by measuring myeloperoxidase activity in mesenteric, epididymal and retroperitoneal areas of adipose tissue. Changes in the expression of inflammatory mediator in these areas of adipose tissue were also evaluated by RT-PCR.

RESULTS

Pancreatitis induces the activation of peritoneal macrophages and a strong inflammatory response in mesenteric and epididymal sites of adipose tissue. By contrast, no changes were found in retroperitoneal adipose tissue. Inhibition of lipase prevented the activation of macrophages and the local inflammation in adipose tissue.

CONCLUSIONS

Our results confirm the involvement of adipose tissue on the progression of systemic inflammatory response during acute pancreatitis. However, there is a considerable diversity in different adipose tissue sites. These differences need to be taken into account in order to understand the progression from local pancreatic damage to systemic inflammation during acute pancreatitis.

[Preparation of rat model of systemic inflammatory response syndrome induced by zymosan]

OBJECTIVE

To establish a model of systemic inflammatory response syndrome (SIRS) in rats.

METHODS

SD rats were intraperitoneally injected with different concentrations of zymosan suspension. The general status, temperature, white cell count, tumor necrosis factor-α(TNF-α), interleukin-6(IL-6), interleukin-10 (IL-10) and the pathological changes of main organs were examined.

RESULTS

The conditions of rats receiving zymosan doses of 750 mg/kg and 1000 mg/kg were consistent with the criteria of SIRS model; however, the mortality of 1000 mg/kg group was higher than that of 750 mg/kg group.

CONCLUSION

The rat model of systemic inflammatory response syndrome has been successfully induced.

Benzylamine and methylamine, substrates of semicarbazide-sensitive amine oxidase, attenuate inflammatory response induced by lipopolysaccharide

Current evidence indicates that semicarbazide-sensitive amine oxidase (SSAO) substrates possess insulin-mimic effect, which was thought to play an anti-inflammatory role. The purpose of the present study was to determine whether SSAO substrates benzylamine (BZA) and methylamine (MA) attenuate inflammatory response induced by lipopolysaccharide (LPS). BALB/c mice peritoneal macrophages (PMs) that express SSAO and RAW264.7 mouse macrophages that do not express SSAO were used in vitro studies. Experimental mice were given BZA or MA through intraperitoneal injection before LPS challenge. The results showed that BZA or MA treatment significantly reduced LPS-induced pro-inflammatory mediators (nitric oxide, TNF-α) production, the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, and glucose consumption in murine PMs, but not in RAW264.7 cell line. The metabolites of BZA or MA catalyzed by SSAO, hydrogen peroxide, formaldehyde, and benzaldehyde could also significantly decrease LPS-induced nitric oxide and TNF-α production, iNOS and COX-2 expression, and glucose consumption in vitro. In addition, BZA or MA administration could significantly decrease plasma pro-inflammatory mediators and the expression of iNOS and COX-2 in liver and lung, and could also attenuate LPS-induced transient hyperglycemia and chronic hypoglycemia. These findings indicated that substrates of SSAO might be involved in the anti-inflammatory effects. The metabolites of BZA and MA catalyzed by SSAO might be responsible for the anti-inflammatory effects. Moreover, BZA or MA administration could be useful for normalization of glucose disposal during endotoxemia.

Associations of primary and secondary organic aerosols with airway and systemic inflammation in an elderly panel cohort

BACKGROUND

Exposure-response information about particulate air-pollution constituents is needed to protect sensitive populations. Particulate matter <2.5 mm (PM2.5) components may induce oxidative stress through reactive-oxygen-species generation, including primary organics from combustion sources and secondary organics from photochemically oxidized volatile organic compounds. We evaluated differences in airway versus systemic inflammatory responses to primary versus secondary organic particle components, particle size fractions, and the potential of particles to induce cellular production of reactive oxygen species.

METHODS

A total of 60 elderly subjects contributed up to 12 weekly measurements of fractional exhaled nitric oxide (NO; airway inflammation biomarker), and plasma interleukin-6 (IL-6; systemic inflammation biomarker). PM2.5 mass fractions were PM0.25 (<0.25 μm) and PM0.25-2.5 (0.25-2.5 μm). Primary organic markers included PM2.5 primary organic carbon, and PM0.25 polycyclic aromatic hydrocarbons and hopanes. Secondary organic markers included PM2.5 secondary organic carbon, and PM0.25 water soluble organic carbon and n-alkanoic acids. Gaseous pollutants included carbon monoxide (CO) and nitrogen oxides (NOx; combustion emissions markers), and ozone (O3; photochemistry marker). To assess PM oxidative potential, we exposed rat alveolar macrophages in vitro to aqueous extracts of PM0.25 filters and measured reactive-oxygen-species production. Biomarker associations with exposures were evaluated with mixed-effects models.

RESULTS

Secondary organic markers, PM0.25-2.5, and O3 were positively associated with exhaled NO. Primary organic markers, PM0.25, CO, and NOx were positively associated with IL-6. Reactive oxygen species were associated with both outcomes.

CONCLUSIONS

Particle effects on airway versus systemic inflammation differ by composition, but overall particle potential to induce generation of cellular reactive oxygen species is related to both outcomes.

Clinical development of onercept, a tumor necrosis factor binding protein, in psoriasis

BACKGROUND

Tumor necrosis factor (TNF)-α plays a critical role in psoriasis pathogenesis, and several anti-TNF agents have been developed as therapeutic drugs in this indication.

SCOPE

To present the preclinical rationale and clinical data for onercept, a novel anti-TNF agent developed for the treatment of moderate-to-severe psoriasis, and to critically evaluate the onercept clinical development program.

FINDINGS

Onercept was shown in preclinical studies to inhibit TNF-α and suppress clinical signs in several inflammatory conditions. In phase II studies onercept demonstrated a therapeutic benefit in psoriasis and psoriatic arthritis and no safety issues were identified. Based on these results, a phase III program comprising three multicenter, randomized, double-blind, placebo-controlled studies examining onercept in moderate-to-severe plaque psoriasis was initiated. Following the occurrence of two cases of systemic inflammatory response syndrome (SIRS) and lower than expected efficacy results, an independent Data Safety Monitoring Board (DSMB) determined that the risk-benefit ratio was not sufficiently favorable to justify continued development, and all clinical studies were promptly terminated. Although not initially diagnosed as such by the investigators, two further SIRS events were reported, one after study discontinuation. Although an increased incidence of infection and sepsis-like events has been associated with other anti-TNF therapies, an increased risk of infection was not observed with onercept treatment. Moreover, no infectious etiology was determined in the SIRS cases. The data suggest that the SIRS reactions were due to a systemic inflammatory response.

CONCLUSIONS

Despite promising early clinical results, onercept showed many of the expected risks associated with other anti-TNF agents and proved not to have an exceptional efficacy and safety profile. The clinical development of onercept highlights the critical importance of DSMBs and closely monitoring patient safety and evaluating risk-benefit profiles in large clinical programs.

Treatment of lymphatic malformations of head and neck with OK-432 sclerotherapy induce systemic inflammatory response

Systemic immune responses after OK-432 (Picibanil) sclerotherapy in patients with head and neck lymphatic malformations (LM) were examined to achieve a better understanding of the mechanism of OK-432 sclerotherapy and to evaluate the long-term treatment outcome. Serum samples from 17 consecutive patients with head and neck LMs were collected during a total of 26 OK-432 treatment episodes. Serum C-reactive protein (CRP), interleukins (IL) 1β, 6, 8, 10, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, RANTES, immune protein (IP)-10 and macrophage chemoattractant protein (MCP)-1 as well as blood leukocyte counts were determined. Clinical outcome of the treatment was evaluated at the last visit and from patient files. Elevated serum levels of IP-10 (means at baseline 702 ng/L, after 1 day 1180 ng/L, after 4 weeks 691 ng/L) were seen on day one after OK-432 sclerotherapy (p < 0.05). C-reactive protein and leukocyte counts 1 day after treatment differed statistically significantly (p < 0.05) from the baseline. No significant differences with other cytokines investigated were observed. Patients with macrocystic LM responded better than patients with microcystic LM (p = 0.01). The elevated levels of IP-10, C-reactive protein and leukocyte levels indicate that OK-432 sclerotherapy induces systemic immune responses in patients with LM. The mechanisms of OK-432 sclerotherapy are still not precisely understood, but the IP-10 elevation may reflect local antiangiogenetic properties of immunoactivation induced by OK-432.

Additives in intravenous anesthesia modulate pulmonary inflammation in a model of LPS-induced respiratory distress

BACKGROUND

It has been suggested that propofol with ethylenediaminetetraacetic acid (EDTA) can modulate the systemic inflammatory response. Prolonged higher levels of pulmonary inflammation are associated with poor outcome of patients with acute lung injury. In the present study, we hypothesized that pulmonary inflammation could be modulated by propofol with EDTA compared with propofol with sulfite.

METHODS

Respiratory distress was induced in rats (n=25) by intratracheal nebulization of lipopolysaccharide (LPS). After 24 h, animals were randomized to either propofol with EDTA (Propofol(EDTA)), propofol with sulfite (Propofol(sulfite)) or ketamine/midazolam (Ket/Mid); control animals received saline (n=30). Animals were ventilated for 4 h and blood gases were measured hourly. Bronchoalveolar lavage (BAL) was performed for cytokine analysis of: tumor necrosis factor (TNF), interleukin (IL)-6 and macrophage inflammatory protein (MIP)-2.

RESULTS

LPS led to increased pulmonary inflammation in all groups compared with the control groups. Gas exchange deteriorated over time only in the LPS Propofol(sulfite) group and was significantly lower than the Ket/Mid group. Only IL-6 was significantly higher in the LPS Propofol(sulfite) group compared with both the Ket/Mid group and the Propofol(EDTA) group.

CONCLUSION

Pulmonary IL-6 can be modulated by additives in systemic anesthesia.

IMPLICATION STATEMENT

This study demonstrates that pulmonary inflammation caused by direct lung injury can be modulated by intravenous anesthesia used in critically ill patients.

Severe systemic inflammatory response syndrome in a patient with adult onset Still's disease treated with the anti-IL1 drug anakinra: a case report

Interleukin 1 (IL1) plays an important role in adult onset Still's disease. Anakinra (Kineret), a recombinant IL1 Receptor Antagonist (IL 1 RA) was therefore recently proposed in adult onset Still's disease with great efficacy. Anakinra appeared to be well tolerated and safe. The case of a patient with refractory adult onset Still's disease who experienced a Systemic Inflammatory Response Syndrome and Adult Respiratory Distress Syndrome requiring intensive care unit hospitalization 10 days after the introduction of anakinra is reported.

Acute systemic inflammation induces central mitochondrial damage and mnesic deficit in adult Swiss mice

The aim of this study was to investigate how the brain is affected during systemic inflammation. For this purpose, Swiss mice were challenged with a single intraperitoneal dose of lipopolysaccharide (LPS; 250microg/mouse) to mimic aspects of systemic infection. Spatial learning in Y-maze test demonstrated a differential learning profile during the training test between control and LPS-treated mice, with an alteration in the latter group. We show that systemic LPS-induced inflammation and oxidative injury as assessed by reactive oxygen species (ROS) and nitrites/nitrates (NOx) production associated with reduced glutathione (GSH) depletion, cyclooxygenase-2 (COX-2) expression, and lipid peroxidation. LPS also induced a loss in mitochondrial integrity as shown by a significant decrease in membrane potential and impairment in mitochondrial redox activity. Thus, peripheral inflammation by producing brain inflammation and oxidative injury causes mnesic deficits. It remains to determine whether such events can induce neuronal dysfunction/degeneration and, with time, lead to cholinergic deficiency, amyloid deposits and cognitive impairments as they occur in Alzheimer's disease.

Intrapulmonary delivery of ricin at high dosage triggers a systemic inflammatory response and glomerular damage

In view of the possibility that ricin may be used as a bioweapon against human populations, we examined the pathological consequences that occur in mice after introduction of ricin into the pulmonary system. Intratracheal instillation of a lethal dose of ricin (20 microg/100 g body weight) resulted in a hemorrhagic inflammatory response in multiple organs, accompanied by activation of mitogen-activated protein kinases, increased synthesis of proinflammatory RNA transcripts, and increased levels of circulating cytokines and chemokines. A sublethal dose of instilled ricin (2 microg/100 g body weight) induced a similar response in lungs but did not cause detectable damage in other organs. Lungs of mice that recovered from a sublethal dose of ricin displayed evidence of fibrosis and residual damage. A lethal dose of ricin caused accumulation of proinflammatory RNA transcripts and substantial damage to 28S rRNA of multiple organs, including lung, kidney, spleen, liver, and blood, demonstrating that instilled ricin gained access to the circulation. The kidneys of mice instilled with a lethal dose of ricin showed accumulation of fibrin/fibrinogen in glomerular capillaries, increased numbers of glomerular leukocytes, and impairment of kidney function. A sublethal dose of ricin failed to induce damage to 28S rRNA in kidney or other extrapulmonary organs.

Prevention of endotoxin-induced systemic response by bone marrow-derived mesenchymal stem cells in mice

Bone marrow-derived mesenchymal stem cells (BMDMSCs) appear to be important in repair of the chronic lung injury caused by bleomycin in mice. To determine effects of these BMDMSCs on an acute inflammatory response, we injected C57BL/6 mice intraperitoneally with 1 mg/kg endotoxin followed either by intravenous infusion of 5 x 10(5) BMDMSCs, the same number of lung fibroblasts, or an equal volume of normal saline solution. Lungs harvested 6, 24, and 48 h and 14 days after endotoxin showed that BMDMSC administration prevented endotoxin-induced lung inflammation, injury, and edema. Although we were able to detect donor cells in the lungs at 1 day after endotoxin, by 14 days no donor cells were detected. BMDMSC administration suppressed the endotoxin-induced increase in circulating proinflammatory cytokines without decreasing circulating levels of anti-inflammatory mediators. Ex vivo cocultures of BMDMSC and lung cells from endotoxemic animals demonstrated a bilateral conversation in which lung cells stimulated proliferation and migration of stem cells and suppressed proinflammatory cytokine production by lung cells. We conclude that BMDMSCs decrease both the systemic and local inflammatory responses induced by endotoxin. These effects do not require either lung engraftment or differentiation of the stem cells and are due at least in part to the production of stem cell chemoattractants by the lungs and to humoral and physical interactions between stem cells and lung cells. We speculate that mobilization of this population of BMDMSCs may be a general mechanism for modulating an acute inflammatory response.

Microcirculatory Dysfunction in the Brain Precedes Changes in Evoked Potentials in Endotoxin-Induced Sepsis Syndrome in Rats

BACKGROUND

During sepsis progression microcirculatory dysfunction precedes macrocirculatory failure, partly explaining the occurrence of early organ dysfunction. The matter concerning microcirculatory dysfunction in the brain under septic conditions is less clear. We investigated the integrity of the activation flow coupling during sepsis progression in a rat model of septic shock.

METHODS

Chloralose-anesthetized rats (n = 30) were subjected to electric forepaw stimulation. Over the somatosensory cortex electrical activity and hemodynamic responses were recorded with surface electrodes and laser Doppler. After baseline recordings, vehicle, 1 or 5 mg/kg lipopolysaccharide (LPS) from Escherichia coli was given intravenously, and activation flow coupling, blood pressure and blood gases were investigated at regular time points up to 270 min. In the end lactate, glucose, neuron-specific enolase (NSE) and S-100B protein levels were measured.

RESULTS

Besides stable data from the control group, all LPS-treated rats developed signs of septic shock, which were more pronounced in the 5 mg/kg LPS group. Cerebral hyperemia occurred and was similar between the sepsis groups despite lower blood pressure levels in the 5 mg/kg LPS group. While the activation flow coupling remained intact in the 1 mg/kg LPS group, an uncoupling occurred in the 5 mg/kg group. First, the evoked flow velocity responses dropped 60 min after sepsis induction before the somatosensory amplitudes also decreased 120 min later. From similar NSE levels we suggest a functional rather than structural deficit explaining the difference in evoked potentials.

CONCLUSIONS

For the first time we demonstrate microcirculatory dysfunction in the activation flow coupling of the brain. Inappropriate blood supply of neurons might explain the disturbance of neuronal function.

Endotoxin-induced cardiomyopathy and systemic inflammation in mice is prevented by aldose reductase inhibition

BACKGROUND

Sepsis is a systemic inflammatory response syndrome characterized by excessive production of inflammatory cytokines and cardiovascular collapse. Postreceptor signaling events that lead to stress responses and cytokine production are sensitive to redox changes and products of lipid peroxidation.

METHODS AND RESULTS

We tested the hypothesis that inflammatory signaling and cytokine generation during sepsis depend on the activity of the enzyme aldose reductase, which catalyzes the reduction of lipid peroxidation-derived aldehydes and their glutathione conjugates. The results of the present study show that pharmacological inhibition of aldose reductase by sorbinil or knockdown of the enzyme by small interfering RNA prevents the activation of nuclear factor-kappaB and the release of tumor necrosis factor-alpha from lipopolysaccharide-stimulated RAW264.7 or H9c2 cells. Increases in serum and cardiac cytokines in response to lipopolysaccharide challenge were suppressed by inhibition of aldose reductase. Treatment with sorbinil blunted the activation of protein kinase C, c-Jun NH2-terminal kinase, and p38, as well as phosphorylation of interleukin receptor-associated kinase, IkappaB-alpha, IkappaB kinase complex-alpha/beta, and phospholipase-gamma1 and -beta1. These changes were associated with decreased myocardial nuclear factor-kappaB and activating protein-1 activity, prostaglandin E2 production, induction of cyclooxygenase 2, and inducible nitric oxide synthase. Sorbinil treatment also induced functional recovery in myocardial fractional shortening in vivo and preserved contractile function of isolated perfused hearts. Inhibition of aldose reductase increased survival in mice injected with lethal doses of lipopolysaccharide.

CONCLUSIONS

The present demonstration that aldose reductase mediates endotoxin-induced inflammation and cardiomyopathy suggests that inhibition of this enzyme may be useful to attenuate maladaptive host responses and to treat acute cardiovascular dysfunction associated with endotoxic shock.

In vivo efficacy of telithromycin on cytokine and nitric oxide formation in lipopolysaccharide-induced acute systemic inflammation in mice

OBJECTIVES

The ketolide telithromycin represents a new subclass of 14-membered semisynthetic macrolides. Because there is evidence that traditional macrolides such as roxithromycin exert anti-inflammatory activity, we investigated the anti-inflammatory action of telithromycin against lipopolysaccharide (LPS)-induced acute systemic inflammation in mice in comparison with roxithromycin.

METHODS

CD-1 mice were injected intraperitoneally with LPS (1 mg/kg), and the effects of pretreatment with a single intraperitoneal dose of telithromycin (150 mg/kg) or roxithromycin (50 mg/kg) for 2 h on the expression and formation of tumour necrosis factor alpha (TNFalpha), interleukin-1 beta (IL-1beta), interferon gamma (IFNgamma) and inducible nitric oxide synthase (NOS-II) as well as nitric oxide (NO) were analysed at different time points after LPS-treatment. Cytokine and NOS-II mRNA abundance was examined using real-time RT-PCR. Tissue cytokine levels were determined by enzyme-linked immunosorbent assay kits (ELISA); NO levels were measured by colorimetric assay kits.

RESULTS

Pretreatment of mice with telithromycin as well as roxithromycin similarly attenuated the LPS-induced expression and formation of TNFalpha, IL-1beta and IFNgamma. Furthermore, the LPS-induced increase of NOS-II mRNA and the formation of NO were clearly diminished.

CONCLUSION

These results suggest that the ketolide telithromycin has anti-inflammatory properties like conventional macrolides due to inhibition of the production of proinflammatory cytokines, which leads to a decreased formation of NO in LPS-treated mice. Our data indicate that ketolides may have beneficial therapeutic effects independent of their antibacterial activity.

INTRANASAL EXPOSURE TO STAPHYLOCOCCAL ENTEROTOXIN B ELICITS AN ACUTE SYSTEMIC INFLAMMATORY RESPONSE

Staphylococcus aureus produces a variety of superantigen exotoxins, including staphylococcal enterotoxin B (SEB). Little is known regarding the pathogenesis of SEB entering through the intranasal route. Intranasal exposure to SEB might occur because of nasal packing following surgical procedure, biologic warfare, or even S. aureus colonization. We evaluated the local and systemic effects of intranasally delivered SEB using a series of human leukocyte antigen (HLA) class II transgenic mice as conventional mice expressing endogenous class II molecules mount a poor immune response to SEB. Gene expression profiling using microarrays showed robust up-regulation of genes involved in several proinflammatory pathways as early as 3 h post-intranasal challenge with SEB in HLA class II transgenic mice. This was accompanied by a several hundred-fold increase in serum levels of pro-inflammatory cytokines such as IL-12, IL-6, TNF-alpha, IFN-gamma, as well as MCP-1 in HLA class II transgenic mice but not in C57BL/6 mice; CD4 or CD8 T-cells independently contributed to the systemic cytokine response. Defective IL-12 or IL-4 receptor signaling significantly decreased or increased serum IFN-gamma, respectively. Intranasal exposure to SEB resulted in neutrophil influx into bronchoalveolar lavage fluid and caused expansion of both CD4 and CD8 T-cells expressing TCR V beta 8 in the spleen. This was accompanied by mononuclear cell infiltration in the liver reminiscent of the systemic inflammatory response syndrome. Thus, we have shown, for the first time, that intranasal administration of SEB can cause systemic immune activation.

Effects of a New Extracorporeal System Using CTR on Mortality and Inflammatory Responses to Bacterial Toxin-Induced Multiple Organ Dysfunction Syndrome in Rabbits

BACKGROUND/AIMS

In the pathogenesis of multiple organ dysfunction syndrome (MODS) caused by bacterial infection, a complex series of systemically secreted bacterial toxins and cytokines are intensely associated. Our previous study demonstrated that a new adsorbent, CTR, was capable of removing cytokines and toxic shock syndrome toxin-1 (TSST-1) in vitro. Moreover, extracorporeal treatment with CTR reduced the high mortality rate and inhibited inflammatory responses in endotoxin-induced shock in rats. However, it is unclear whether CTR treatment will be an effective therapy for MODS. Here, we demonstrated the efficacy of a new extracorporeal system using CTR on MODS induced by bacterial toxins in rabbits.

METHODS

Direct hemoperfusion (DHP) apheresis with or without CTR for 120 min was performed in rabbits that had been intravenously infused with endotoxin and TSST-1. The mean arterial pressure was recorded and the plasma toxin and cytokine concentrations were measured during the treatment period. Mortality was assessed up to 7 days after exposure to the toxins. In addition, tissues specimens were examined using microscopy.

RESULTS

The mortality rates at 7 days after the injection of the toxins were 90 and 10% for the control and CTR groups, respectively. The plasma concentrations of TSST-1, tumor necrosis factor and interleukin-1 beta in the CTR group were significantly lower than those in the control group. Histopathological examination revealed that tissue damage, such as necrosis and depletion of lymphocytes in the spleen and mesenteric lymph node, was reduced in the CTR group, compared with that in the control group, at 24 h after toxin infusion.

CONCLUSION

The new adsorbent CTR improved the mortality rate in a MODS rabbit model by adsorbing TSST-1 and cytokines. Further development of CTR may expand the scope of extracorporeal therapies for patients with MODS.

Central muscarinic cholinergic regulation of the systemic inflammatory response during endotoxemia

TNF has a critical mediator role in inflammation and is an important therapeutic target. We recently discovered that TNF production is regulated by neural signals through the vagus nerve. Activation of this "cholinergic antiinflammatory pathway" inhibits the production of TNF and other cytokines and protects animals from the inflammatory damage caused by endotoxemia and severe sepsis. Here, we describe a role for central muscarinic acetylcholine receptors in the activation of the cholinergic antiinflammatory pathway. Central muscarinic cholinergic activation by muscarine, the M1 receptor agonist McN-A-343, and the M2 receptor antagonist methoctramine inhibited serum TNF levels significantly during endotoxemia. Centrally administered methoctramine stimulated vagus-nerve activity measured by changes in instantaneous heart-rate variability. Blockade of peripheral muscarinic receptors did not abolish antiinflammatory signaling through the vagus nerve, indicating that peripheral muscarinic receptors on immune cells are not required for the cytokine-regulating activities of the cholinergic antiinflammatory pathway. The role of central muscarinic receptors in activating the cholinergic antiinflammatory pathway is of interest for the use of centrally acting muscarinic cholinergic enhancers as antiinflammatory agents.

Rebound phenomenon of inflammatory response may be a major mechanism responsible for increased cardiovascular events after abrupt cessation of statin therapy

Inflammation has been recognized as having an important role in the development and progression of atherosclerosis. Statins reduce cardiovascular events mainly by cholesterol lowering. A large number of investigations have demonstrated that administration of statin could modify inflammatory response with a concurrent fall in cardiovascular events. Despite the known benefit of statin therapy, many cardiac patients abruptly discontinue therapy because of financial constraints, forgetfulness, or side effects. More recently, several studies have shown that abrupt cessation of statin therapy during treatment could increase the incidence of cardiac events in patients with atherosclerotic heart disease. However, the mechanisms of the increased incidence of cardiovascular events after abruptly stopping statin therapy are still unknown. A few data suggest that abrupt withdrawal of statin therapy deteriorates endothelial function, result in expression of pro-inflammatory gene involved in the development and progression of atherosclerosis. We hypothesis that rebound phenomenon of inflammatory response may be a major mechanism responsible for increased cardiovascular events after abrupt cessation of statin therapy. Our very recent data showed that abrupt termination of statin therapy resulted in a rapid increased C-reactive protein (CRP) and interleukin-6 (IL-6) levels in patients with hypercholesterolemia. This finding may be of important interest in the connection between inflammatory response and abrupt withdrawal of statin therapy in patients with coronary artery disease.

Role of metallothionein in coagulatory disturbance and systemic inflammation induced by lipopolysaccharide in mice

Although metallothionein (MT) can be induced by inflammatory mediators, its roles in coagulatory disturbance during inflammation are poorly defined. We determined whether MT protects against coagulatory and fibrinolytic disturbance and systemic inflammation induced by intraperitoneal administration of lipopolysaccharide (LPS) in MT-I/II null (-/-) and wild-type (WT) mice. As compared with WT mice, MT (-/-) mice revealed significant prolongation of prothrombin and activated partial thromboplastin time, a significant increase in the levels of fibrinogen and fibrinogen/fibrin degradation products, and a significant decrease in activated protein C, after LPS treatment. LPS induced inflammatory organ damages in the lung, kidney, and liver in both genotypes of mice. The damages, including neutrophil infiltration, were more prominent in MT (-/-) mice than in WT mice after LPS treatment. In both genotypes of mice, LPS enhanced protein expression of interleukin (IL)-1beta, IL-6, granulocyte/macrophage-colony-stimulating factor, macrophage inflammatory protein (MIP)-1alpha, MIP-2, macrophage chemoattractant protein-1, and keratinocyte chemoattractant in the lung, kidney, and liver and circulatory levels of IL-1beta, IL-6, MIP-2, and KC. In overall trends, however, the levels of these proinflammatory proteins were greater in MT (-/-) mice than in WT mice after LPS challenge. Our results suggest that MT protects against coagulatory and fibrinolytic disturbance and multiple organ damages induced by LPS, at least partly, via the inhibition of the expression of proinflammatory proteins.

Critical protective role for annexin 1 gene expression in the endotoxemic murine microcirculation

The inflammatory response is a protective process of the body to counteract xenobiotic penetration and injury, although in disease this response can become deregulated. There are endogenous biochemical pathways that operate in the host to keep inflammation under control. Here we demonstrate that the counterregulator annexin 1 (AnxA1) is critical for controlling experimental endotoxemia. Lipopolysaccharide (LPS) markedly activated the AnxA1 gene in epithelial cells, neutrophils, and peritoneal, mesenteric, and alveolar macrophages--cell types known to function in experimental endotoxemia. Administration of LPS to AnxA1-deficient mice produced a toxic response characterized by organ injury and lethality within 48 hours, a phenotype rescued by exogenous application of low doses of the protein. In the absence of AnxA1, LPS generated a deregulated cellular and cytokine response with a marked degree of leukocyte adhesion in the microcirculation. Analysis of LPS receptor expression in AnxA1-null macrophages indicated an aberrant expression of Toll-like receptor 4. In conclusion, this study has detailed cellular and biochemical alterations associated with AnxA1 gene deletion and highlighted the impact of this protective circuit for the correct functioning of the homeostatic response to sublethal doses of LPS.

The isolated perfused liver response to a 'second hit' of portal endotoxin during severe acute pancreatitis

BACKGROUND/AIM

During severe acute pancreatitis (AP), the liver may show an exaggerated response to the inflammatory products of gut injury transported in the portal vein. Our aim was to explore liver proinflammatory mediator production after a 'second hit' of portal lipopolysaccharide (LPS) during AP.

METHODS

Twenty-four rats underwent one of three 'first-hit' scenarios: (1) severe AP induced by intraductal glycodeoxycholic acid injection and intravenous caerulein infusion, (2) sham laparotomy, or (3) no first intervention. Eighteen hours later, all animals received a 'second hit' of portal LPS in an isolated liver perfusion system. Tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, and IL-6 concentrations were measured in portal and systemic serum, and in the perfusate 30 and 90 min after the 'second hit'. Neutrophil activation by the perfusate was assayed using dihydrorhodamine-123 fluorescence.

RESULTS

We observed a six-fold increase in IL-6 concentration across the liver during AP. All livers produced TNF-alpha after the portal LPS challenge, but this was not exaggerated by AP. No differential neutrophil activation by the perfusate was seen.

CONCLUSION

TNF-alpha, IL-1beta, IL-6 and neutrophil activator production by the isolated perfused liver, in response to a 'second hit' of portal LPS, does not appear to be enhanced during AP.

Subcutaneous injection of interleukin 12 induces systemic inflammatory responses in humans: implications for the use of IL-12 as vaccine adjuvant

Interleukin 12 (IL-12) is a cytokine with important regulatory functions bridging innate and adaptive immunity. It has been proposed as an immune adjuvant for vaccination therapy of infectious diseases and malignancies. The inflammatory properties of IL-12 play an important role in the adjuvant effect. We studied the effect of s.c. injections of recombinant human IL-12 (rHuIL-12) in 26 patients with renal cell cancer and demonstrated dose-dependent systemic activation of multiple inflammatory mediator systems in humans. rHuIL-12 at a dose of 0.5 microg/kg induced degranulation of neutrophils with a significant increase in the plasma levels of elastase (p < 0.05) and lactoferrin (p = 0.01) at 24 h. Additionally, rHuIL-12 injection mediated the release of lipid mediators, as demonstrated by a sharp increase in the plasma secretory phospholipase A2 (sPLA2) level (p = 0.003). rHuIL-12, when administered at a dose of 0.1 microg/kg, showed minimal systemic effects. In conclusion, when IL-12 is used as an adjuvant, doses should not exceed 0.1 microg/kg, in order to avoid severe systemic inflammatory responses.

Histophatological changes and inflammatory response induced by Tityus discrepans scorpion venom in rams

Anesthetized rams envenomed s.c. with 40 microg/kg Tityus discrepans scorpion venom developed fasciculation, hypothermia, polyuria, pulmonary wet rales, tachypnea, respiratory distress and arrhythmia. Rams developed a cascade of inflammation reactions, characterized by activation of macrophages, fibroblasts and neutrophils, neutrophil infiltration and aggregation, vasculitis, arteritis and abundant fibrin deposition. At the inoculation site, venom was detected by immunohistochemistry in the extra cellular matrix, lymphatic vessels' and venules' lumen, inside macrophages and surrounding nerves. Extra cellular matrix was degraded at the inoculation site perhaps by activated neutrophils. Envenoming produced hepatocytes with Mallory body-like vacuoles which may be due to the increased plasmatic levels of TNF-alpha and IL6. Venom produced degranulation and vacuolization of acinary cells as well as interstitial swelling and necrosis. Necrosis of the Langerhan's islets occurred occasionally. Lungs showed the most deleterious effects developing wall collapse and necrosis, diffuse injury of the alveolar capillary barrier, interstitial and alveolar fibrin deposits with strong neutrophil infiltration. Massive infiltration of lymphocytes and macrophage occurred in the intestinal submucose, to the point that it modified villi and intestinal folding morphology. Envenomation developed a marked leukocyte aggregation surrounding nerves at the inoculation site. This study reveals that beyond its neurotoxicity, Tityus venom produces a severe and widespread inflammatory syndrome, expressed as histopathological changes at the site of inoculation, as well as in remote organs such as pancreas, lungs, intestine and liver. Our results suggest that not all remote targets are directly affected by the venom but that, as proposed earlier, are modified by inflammation by products produced elsewhere.