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

The expression of proinflammatory and immunoregulatory cytokines rapidly increases in the lungs after hemorrhage, and such alterations contribute to the frequent development of acute inflammatory lung injury in this setting. Blood loss also produces elevations in catecholamine concentrations in the pulmonary and systemic circulation. In the present experiments, we used alpha- and beta-adrenergic receptor blockade to examine in vivo interactions between hemorrhage-induced adrenergic stimulation and pulmonary cytokine expression. Treatment of mice with the alpha-adrenergic receptor antagonist phentolamine prevented not only the elevation in mRNA levels of IL-1beta, TNF-alpha, and TGF-beta1, the increase in IL-1beta protein, but also the activation of nuclear factor (NF)-KB and cyclic AMP response element binding protein, which occurred in lung cells of untreated animals during the first hour after hemorrhage. In contrast, treatment before hemorrhage with the beta-adrenergic receptor antagonist propranolol was associated with increases in mRNA levels for IL-1beta, TNF-alpha, and TGF-beta1, which were greater than those present in untreated hemorrhaged mice, and did not prevent hemorrhage-associated increases in lung IL-1beta protein. Treatment with propranolol prevented hemorrhage-induced phosphorylation of cyclic AMP response element binding protein, but increased hemorrhage-associated activation of NF-KB. These results demonstrate that hemorrhage initially increases pulmonary cytokine expression through alpha- but not beta-adrenergic stimulation, and suggest that such alpha-adrenergic-mediated effects occur through activation of the transcriptional regulatory factor NF-kappaB.

Therapies for sepsis. Emerging therapies for sepsis and septic shock

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Hemorrhage induces rapid in vivo activation of CREB and NF-kappaB in murine intraparenchymal lung mononuclear cells

Increased expression of proinflammatory cytokines appears to be an important factor contributing to the development of acute lung injury. In murine models, mRNA levels of proinflammatory and immunoregulatory cytokines, including IL-1alpha, IL-1beta, TGF-beta1, and TNF-alpha, are increased in intraparenchymal lung mononuclear cells 1 h after hemorrhage. Binding elements for the nuclear transcriptional regulatory factors, nuclear factor kappaB (NF-kappaB), CCAAT/enhancer binding protein beta (C/EBPbeta), serum protein 1 (Sp1), activator protein 1 (AP-1), and the cyclic AMP response-element binding protein (CREB) are present in the promoter regions of numerous cytokine genes, including those whose expression is increased after blood loss. To investigate early transcriptional mechanisms which may be involved in regulating pulmonary cytokine expression after hemorrhage, we examined in vivo activation of these five nuclear transcriptional factors among intraparenchymal lung mononuclear cells obtained in the immediate post-hemorrhage period. Activation of NF-kappaB and CREB, but not C/EBPbeta, Sp1, or AP-1, was present in lung mononuclear cells isolated from mice 15 min after hemorrhage. Inhibition of xanthine oxidase by prior feeding with either an allopurinol-supplemented or a tungsten-enriched diet prevented hemorrhage-induced activation of CREB, but not NF-kappaB. These results demonstrate that hemorrhage leads to rapid in vivo activation in the lung of CREB through a xanthine oxidase-dependent mechanism and of NF-kappaB through other pathways, and suggest that the activation of these transcriptional factors may have an important role in regulating pulmonary cytokine expression and the development of acute lung injury after blood loss.

A review of neurological sequelae and cognitive deficits associated with antiphospholipid antibodies

Antiphospholipid Antibodies (aPAs) are specific circulating immunoglobulins that lead to a hypercoagulant state and recurrent arterial and venous thromboembolic events. The cerebral circulation is the most common site of arterial occlusion in aPAs, and neurologic events include amaurosis fugax, migrainous cephalalgia, transient ischemic attacks (TIA), stroke, ischemic encephalopathy, and vascular dementia. A review of the literature yields numerous studies citing neurocognitive and neuropsychiatric symptoms associated with this syndrome in a much younger population than is seen in other cerebrovascular disorders. These associated features include focal and generalized cognitive deficits, early-onset vascular dementia, and neuropsychiatric symptoms such as affective and thought disorders. These neurocognitive and neurobehavioral manifestations may be underemphasized in this population and aPAs should be considered in a differential diagnosis. Largescale prospective studies are needed to quantify psychiatric and neuropsychological sequelae of this disorder.

Hyperoxia activates NF-kappaB and increases TNF-alpha and IFN-gamma gene expression in mouse pulmonary lymphocytes

Hyperoxia-associated production of reactive oxygen species leads to neutrophil infiltration into the lungs and increased pulmonary proinflammatory cytokine expression. However, the initial events induced by hyperoxia, and leading to acute inflammatory lung injury, remain incompletely characterized. To explore this issue, we examined nuclear transcriptional regulatory factor (NF-kappaB and NF-IL-6) activation and cytokine expression in the lungs following 12 to 48 h of hyperoxia exposure. No increases in cytokine (IL-1beta, IL-6, IL-10, TGF-beta, TNF-alpha, IFN-gamma) expression nor in NF-kappaB activation were found after 12 h of hyperoxia. Following 24 h of hyperoxia, NF-kappaB activation and increased levels of TNF-alpha mRNA were present in pulmonary lymphocytes. By 48 h of hyperoxia, amounts of IFN-gamma and TNF-alpha protein as well as mRNA were increased in the lungs, and NF-kappaB continued to show activation, even though no histologic abnormalities were present. These results show that hyperoxia activates NF-kappaB in the lungs before any increase in proinflammatory cytokine protein occurs, and suggest that NF-kappaB activation may represent an initial event in the proinflammatory sequence induced by hyperoxia.

Hyperoxia activates NF-kappaB and increases TNF-alpha and IFN-gamma gene expression in mouse pulmonary lymphocytes

Hyperoxia-associated production of reactive oxygen species leads to neutrophil infiltration into the lungs and increased pulmonary proinflammatory cytokine expression. However, the initial events induced by hyperoxia, and leading to acute inflammatory lung injury, remain incompletely characterized. To explore this issue, we examined nuclear transcriptional regulatory factor (NF-kappaB and NF-IL-6) activation and cytokine expression in the lungs following 12 to 48 h of hyperoxia exposure. No increases in cytokine (IL-1beta, IL-6, IL-10, TGF-beta, TNF-alpha, IFN-gamma) expression nor in NF-kappaB activation were found after 12 h of hyperoxia. Following 24 h of hyperoxia, NF-kappaB activation and increased levels of TNF-alpha mRNA were present in pulmonary lymphocytes. By 48 h of hyperoxia, amounts of IFN-gamma and TNF-alpha protein as well as mRNA were increased in the lungs, and NF-kappaB continued to show activation, even though no histologic abnormalities were present. These results show that hyperoxia activates NF-kappaB in the lungs before any increase in proinflammatory cytokine protein occurs, and suggest that NF-kappaB activation may represent an initial event in the proinflammatory sequence induced by hyperoxia.

Supramalleolar osteotomy for ankle valgus in myelomeningocele

Fifty-five supramalleolar osteotomies were performed in 35 patients for progressive hindfoot valgus in myelomeningocele. All patients were ambulatory. The most common motor level of innervation was L3 in 42 limbs. The average age at surgery was 12 years. The average follow-up was 8 years. Preoperatively, all patients experienced progressive difficulty with brace use, and anteroposterior weight-bearing ankle radiographs showed a valgus tilt of the talotibial angle (TTA) of > or = 10 degrees with an average of 18 degrees. The average postoperative correction of TTA was 17 degrees. The results were graded as follows: excellent, 42 limbs; good, eight limbs; fair, three limbs; and poor, two limbs. The fair and poor limb results were the result of loss of correction or nonunion. The best results were seen when the TTA was corrected to 5 degrees of varus.

Nuclear factor-kappa B is activated in alveolar macrophages from patients with acute respiratory distress syndrome

OBJECTIVE

The expression of proinflammatory cytokines is rapidly increased in experimental models of the acute respiratory distress syndrome (ARDS), in patients at risk for ARDS, and in patients with established ARDS. Because multiple cytokines are present in bronchoalveolar lavage fluid, a common, proximal activation mechanism may operate in these settings. The proinflammatory cytokines whose expression is increased in the lungs of patients with ARDS have binding sequences in their enhancer/promoter regions for transcriptional regulatory proteins, such as nuclear factor-kappa B (NF-kappa B), nuclear factor-IL6 (NF-IL6), cyclic adenosine monophosphate responsive element binding protein, serum protein-1, and activating protein-1. To test the hypothesis that activation of one or more of these nuclear transcriptional regulatory factors might provide a common mechanism for the simultaneous expression of multiple cytokine genes in the setting of ARDS, we measured activation of these factors in alveolar macrophages from patients with ARDS and from controls.

DESIGN

Prospective, clinical study.

SETTING

Medical and surgical intensive care units at a university hospital and a county hospital.

PATIENTS

Twelve patients, six with established ARDS and six control patients without lung injury.

INTERVENTIONS

Patients with ARDS and controls underwent fiberoptic bronchoscopy and bronchoalveolar lavage. Alveolar macrophages were isolated from lavage fluid and the nuclear proteins were extracted. Activation of transcriptional factors NF-kappa B, NF-IL6, cyclic adenosine monophosphate responsive element binding protein, activating protein-1, and serum protein-1 was determined using an electrophoretic mobility shift assay, followed by densitometry of the autoradiographed gels.

MEASUREMENTS AND MAIN RESULTS

There were no significant differences in gender, age, tobacco smoking, Acute Physiology and Chronic Health Evaluation II score, quantity of lavage fluid, or number of alveolar macrophages in lavage specimens in the patient groups. Acute Lung Injury score and the Pao2/Fio2 ratio differed significantly between controls and ARDS patients: 0.46 +/- 0.17 vs. 2.74 +/- 0.14 (p < .0001) and 310 +/- 45 torr (41.3 +/- 6.0 kPa) vs. 150 +/- 11 torr (21.3 +/- 1.5 kPa) (p < .006), respectively. The mean Fio2 of the control patients was not significantly different from the mean Fio2 of ARDS patients: 0.47 +/- 0.11 vs. 0.55 +/- 0.6 (p = .53). Patients with ARDS had significantly (p < .02) increased activation of NF-kappa B in alveolar macrophages compared with patients without the syndrome. There was no evidence of increased activation of the transcriptional factors activating protein-1, serum protein-1, NF-IL6, or cyclic adenosine monophosphate responsive element binding protein in alveolar macrophages from ARDS vs. control patients.

CONCLUSIONS

These experiments demonstrated increased in vivo activation of the nuclear transcriptional regulatory factor NF-kappa B (but not NF-IL6, cyclic adenosine monophosphate responsive element binding protein, activating protein-1, or serum protein-1) in alveolar macrophages from patients with ARDS. Because binding sequences for NF-kappa B are present in the enhancer/promoter sequences of multiple proinflammatory cytokines, activation of NF-kappa B may contribute to the increased expression of multiple cytokines in the lung in the setting of established ARDS.

An increase in serum C18 unsaturated free fatty acids as a predictor of the development of acute respiratory distress syndrome

OBJECTIVE

No means exist for predicting the acute respiratory distress syndrome (ARDS), which complicates sepsis, trauma, and a variety of clinical disorders. Because activation of phospholipid-signaling pathways involving the acyl chains oleate and linoleate may initiate and amplify the inflammatory response, and thereby lead to the development of ARDS, we examined whether serum concentrations of these bioactive lipids increase and are predictive of ARDS in at-risk patients.

DESIGN

Part I: A prospective, single-blind trial. Part II: A prospective, randomized, double-blind trial.

SETTING

General intensive therapy units in five university teaching hospitals.

SUBJECTS

Part I: Thirty-nine healthy control patients were studied to determine normal distribution of serum acyl values, followed by 30 patients admitted with onset of sepsis, trauma, or development of ARDS (within 24 hrs of admission) over a 1-yr period. Part II: Eight patients admitted with sepsis syndrome over a 2-month period.

INTERVENTIONS

Part II: Patients were randomized to receive the substituted methylxanthine, lisofylline (CT1501R), or an identically presented placebo.

MEASUREMENTS AND MAIN RESULTS

We measured the serum free fatty acid concentrations in the 39 healthy control subjects, and then we prospectively examined the serum free fatty acid concentrations in 30 age-matched patients in samples obtained within 24 hrs from the onset of sepsis, trauma, or development of ARDS. We then prospectively studied eight septic, at-risk patients who were matched for age, Acute Physiology and Chronic Health Evaluation II scores, Multiple Organ Failure index, and Glasgow Coma Score, in a double-blind, placebo-controlled, pilot study. These patients included four patients who received no treatment and four patients who received lisofylline, a compound that decreases serum unsaturated free fatty acids and diminishes acute lung injury in animals caused by sepsis and/or trauma. The calculated ratios of serum free fatty acids (Le., the ratio of C18 unsaturated fatty acids linoleate and oleate to fully saturated palmitate, C16:0) increased and predicted the development of ARDS in at-risk patients. Serum samples from the 30 patients, obtained within 24 hrs from the onset of sepsis, trauma, or development of ARDS, had significantly increased mean acyl chain ratios (1.42 +/- 0.35 [SD]) compared with healthy control subjects (0.86 +/- 0.25; p < .01). Sera from 13 patients with sepsis or trauma who did not develop ARDS (group A [at-risk, non-pre-ARDS]) also had increased acyl ratios (1.23 +/- 0.27) compared with sera from healthy control subjects (0.86 +/- 0.25; p < .01). Sera from seven patients who subsequently developed ARDS (group B [at-risk, pre-ARDS]) had higher acyl ratios (1.70 +/- 0.21) than group A at-risk patients who did not develop ARDS (1.23 +/- 0.27; p < .01) or healthy control subjects (0.86 +/- 0.25; p < .001). Sera from ten group C patients with ARDS at the time of admission to the study had the highest acyl ratios (1.80 +/- 0.75), which exceeded values for healthy control subjects (p < .001) and group A at-risk patients without ARDS (p = .01), but were not significantly different then group B at-risk, pre-ARDS patients (p = .17). Prospective study of eight septic, at-risk patients demonstrated significantly (p < .05) increased serum acyl ratios in the four untreated patients (findings consistent with the first study) but a significantly (p = .02) reduced ratio in the four at-risk patients treated with lisofyline.

CONCLUSIONS

Increases in unsaturated serum acyl chain ratios differentiate between healthy and seriously iII patients, and identify those patients likely to develop ARDS. Thus, the serum acyl ratio may not only prospectively identify and facilitate the assessment of new treatments in patients at highest risk for developing ARDS, but may also lead to new insights about the pathogenesis of ARDS.

Treatment of septic shock with the tumor necrosis factor receptor:Fc fusion protein. The Soluble TNF Receptor Sepsis Study Group

BACKGROUND

A recombinant, soluble fusion protein that is a dimer of an extracellular portion of the human tumor necrosis factor (TNF) receptor and the Fc portion of IgG1 (TNFR:Fc) binds and neutralizes TNF-alpha and prevents death in animal models of bacteremia and endotoxemia.

METHODS

To evaluate the safety and efficacy of TNFR:Fc in the treatment of septic shock, we conducted a randomized, double-blind, placebo-controlled, multicenter trial. A total of 141 patients were randomly assigned to receive either placebo or a single intravenous infusion of one of three doses of TNFR:Fc (0.15, 0.45, or 1.5 mg per kilogram of body weight). The primary end point was mortality from all causes at 28 days.

RESULTS

There were 10 deaths among the 33 patients in the placebo group (30 percent mortality), 9 deaths among the 30 patients receiving the low dose of TNFR:Fc (30 percent mortality), 14 deaths among the 29 receiving the middle dose (48 percent mortality), and 26 deaths among the 49 receiving the high dose (53 percent mortality) (P = 0.02 for the dose-response relation). Baseline differences in the severity of illness did not account for the increased mortality in the groups receiving the higher doses of TNFR:Fc.

CONCLUSIONS

In patients with septic shock, treatment with the TNFR:Fc fusion protein does not reduce mortality, and higher doses appear to be associated with increased mortality.

Clinical evaluation of a multiparameter intra-arterial blood-gas sensor

OBJECTIVE

To evaluate the in vivo performance of a continuous, intra-arterial, multiparameter blood-gas sensor containing a thermocouple, miniaturized polarographic oxygen electrode, as well as fiberoptic pH and pCO2 sensors.

DESIGN

Prospective, multicenter study comparing pH, PaCO2, and PaO2 measurements from the intraarterial sensor with those obtained from a conventional, laboratory blood-gas monitor.

SETTING

Intensive care units in three academic medical centers.

PATIENTS

Adult ICU patients (n = 26) with a clinical need for a radial artery catheter and frequent monitoring of arterial blood gases for > or = 3 days.

INTERVENTIONS

All patients had the multiparameter intra-arterial sensor placed through a 20-gauge catheter into the radial artery. Every 4 h, or more frequently if clinically indicated, a blood-gas sample was withdrawn from the radial artery catheter and sent to the laboratory for analysis using a conventional laboratory blood-gas analyzer. Immediately prior to withdrawal of the arterial blood, values for pH, PaCO2, and PaO2 from the multiparameter intra-arterial sensor were recorded.

MEASUREMENTS AND MAIN RESULTS

The multiparameter sensor was placed into 26 patients. In 7 of the patients, premature discontinuation of monitoring was necessary because of dampening of the pressure tracing, difficulty in withdrawing blood from the arterial catheter, or bending of the extra-arterial fiberoptic channel owing to the cable being inadequately secured (mean monitoring time in these 7 patients: 40.6 +/- 25.7 h). In the other 19 patients, monitoring was continued until no longer clinically indicated. In these patients, a total of 341 data sets was collected, with the average length of monitoring being 69.9 +/- 37.9 h (range 22.0 to 57.9 h). Comparison of the sensor values with those from the blood-gas analyzer showed bias and precision values of 0.006 and 0.026 for arterial pH - 1.19% and 12.54% for PaO2, and 1.28 mmHg and 2.48 mmHg for PaCO2, respectively. No complications were associated with the intra-arterial sensor.

CONCLUSIONS

Clinical performance of this intra-arterial, multiparameter blood-gas sensor demonstrated stability, consistency, and accuracy comparable to laboratory blood-gas analyzers. The present multiparameter, intravascular blood-gas sensor, when inserted in the radial artery, can provide stable and accurate monitoring of pH, PaCO2, and PaO2 over clinically relevant periods of as long as 6 days in the critical care setting.

Alterations in transcriptional regulation of proinflammatory and immunoregulatory cytokine expression by hemorrhage, injury, and critical illness

Transcriptional factors which bind to the promoter regions of genes play an important role in regulating gene expression. The transcription of immunoregulatory and proinflammatory cytokines as well as other proteins known to be important in producing organ system injury after trauma, blood loss, or sepsis is controlled both by the activation of transcriptional regulatory factors and by the interactions of these transcriptional factors with each other, resulting in augmentation or suppression of gene transcription. Most of the transcriptional factors which appear to play a role in modulating immune response in the setting of critical illness can be activated through several different pathways, often involving intracellular redox state and cytokine or endotoxin interaction with membrane receptors. In the severely injured patient, many of these activating mechanisms appear to be operative. Modulation of gene transcription, particularly in those organ systems (e.g., the lungs) which are most vulnerable to inflammatory injury, may be an important therapeutic target in critically ill patients.

Hemorrhage activates NF-kappa B in murine lung mononuclear cells in vivo

Hemorrhage rapidly increases the expression of proinflammatory and immunoregulatory cytokines in the lungs. Binding elements for the nuclear transcriptional regulatory factors (NF)-kappa B and NF-IL6 (C/EBP beta) are present in the promoter regions of multiple cytokine genes, including those whose expression is increased after blood loss. In the present experiments, we found increased activation in vivo of NF-kappa B in lung mononuclear cells, but not in splenocytes, taken from mice 1 h after hemorrhage. In contrast, hemorrhage did not activate NF-IL6 in lung cells or splenocytes. Inhibition of xanthine oxidase by prior feeding of a tungsten-enriched diet prevented hemorrhage-induced activation in lung cells of NF-kappa B. Incubating splenocytes in vitro with xanthine oxidase activated NF-kappa B but not NF-IL6. Xanthine oxidase-induced activation of NF-kappa B was inhibited by manganese superoxide dismutase, but not by catalase. These results suggest that xanthine oxidase-mediated superoxide anion-dependent activation of NF-kappa B occurs in vivo and in vitro. This mechanism may contribute to increased lung cytokine responses after hemorrhage.

Plasma from hemorrhaged mice activates CREB and increases cytokine expression in lung mononuclear cells through a xanthine oxidase-dependent mechanism

Hemorrhage rapidly increases plasma xanthine oxidase levels as well as the expression of proinflammatory and immunoregulatory cytokines in the lungs. To determine the role of circulating xanthine oxidase (XO), as well as other plasma factors, in affecting pulmonary cytokine expression, we conducted studies in which plasma from hemorrhaged mice was transferred into unhemorrhaged recipient mice. Administration of posthemorrhage plasma to recipient mice increased the levels of mRNA for interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), and transforming growth factor-beta 1 (TGF-beta 1) in lung mononuclear cells. No enhancement of mRNA levels for these cytokines was found in the lungs of mice given allopurinol-treated posthemorrhage plasma or fed a tungsten-enriched, XO-depleting diet prior to transfer of posthemorrhage plasma. Among the nuclear transcriptional regulatory factors examined, only the cyclic AMP response-element binding protein (CREB) was activated in nuclear extracts from lung mononuclear cells of mice that were given posthemorrhage plasma. No activation of nuclear factor-kappa B (NF-kappa B), nuclear factor interleukin 6 (NF-IL6), activating protein-1 (AP-1), or serum protein-1 (SP-1) was found. These results suggest that the mechanism for hemorrhage-induced increases in pulmonary cytokine expression is by activation of the enhancer CREB through a tissue XO-dependent pathway initiated by plasma-borne mediators.

WAIS-R verbal-performance IQ discrepancies in persons with lateralized lesions: utility of a seven subtest short form

WAIS-R Verbal-Performance IQ difference scores for Ward's (1990) seven subtest short form and the complete WAIS-R were examined in patients with lateralized and diffuse lesions. For both versions, the expected Performance > Verbal pattern was observed in the right hemisphere lesion group, while no summary score differences were seen in the left hemisphere group. Verbal-Performance IQ discrepancies for the short form fell within +/- 5 points of the WAIS-R discrepancy scores in about 75%of the cases, regardless of lesion location. Statistically reliable IQ differences between the complete and abbreviated WAIS-R attained 66%, 91%, and 89% agreement for the left, right, and diffuse groups, respectively. The results support the clinical utility of the seven subtest short form.