Neutrophil elastase inhibitor improves survival of rats with clinically relevant sepsis.

Sivelestat sodium hydrate is a selective inhibitor of neutrophil elastase, which is effective in acute lung injury associated with systemic inflammatory response syndrome. However, the effectiveness of sivelestat in sepsis has not been fully examined. In the present study, the effect of sivelestat on severe sepsis in a rat cecal ligation and puncture (CLP) model was investigated. Adult male Sprague-Dawley rats underwent CLP and were randomly divided into two groups: sivelestat-treated group and saline-treated controls. The serum concentrations of several inflammatory mediators were measured. Hematoxylin-eosin staining, and immunohistochemical staining for high-mobility group box chromosomal protein 1 (HMGB1), IL-8, and CD68 were performed on the lungs to assess pathological changes found 12 h after the CLP procedure. Treatment with sivelestat significantly improved the survival rate of the post-CLP septic animals (P = 0.030). Sivelestat also induced a significant reduction in serum IL-1beta (P = 0.038) and IL-10 (P = 0.008) levels in these CLP rats. Serum HMGB1 levels had no significant difference between the sivelestat-treated and the control group. The lungs from sivelestat-treated rats exhibited less severe pathological changes and decreased the numbers of HMGB1, IL-8, and CD68-positive cells (P < 0.001). Sivelestat significantly improved survival rate of rats with clinically relevant sepsis, possibly by attenuating sepsis-induced systemic inflammatory response and lung injury. This may explain the implicated health benefits of sivelestat in reducing morbidity and mortality from sepsis.

Neutrophil elastase activity in acute lung injury and respiratory distress syndrome.

BACKGROUND AND OBJECTIVE: Neutrophil elastase (NE) may play a key role in the development of acute lung injury (ALI) or ARDS. NE activity (NEA) was measured in patients with ALI treated with a selective NE inhibitor. METHODS: NEA and NE-alpha1-antitrypsin (NE-AT) complex were measured in plasma before, during and after the administration of the selective NE inhibitor, sivelestat, in 32 patients with a diagnosis of ALI or ARDS. NEA index (NEAI) was calculated as NEA/NE-AT. The sequential organ failure assessment (SOFA) score and the ratio PaO(2)/fraction of inspired oxygen (FiO(2)) were measured. RESULTS: NEA and NE-AT was raised in all patients. Sivelestat reduced NEAI and NEA (P < 0.01 for both) but not NE-AT and NEA, and NEAI returned to pretreatment levels. NEA correlated closely with NE-AT before, but not after treatment. No relationship was observed between these indices and SOFA score or PaO(2)/FiO(2) ratio. CONCLUSIONS: Sivelestat reduced NEA and NEAI in patients with ALI or ARDS suggesting NE inhibition. A larger study is needed to determine the relationship of NEA, NE-AT and NEAI with the outcome of ALI/ARDS.

Serum S-100B protein levels in left- and right-hemisphere strokes.

S-100B is a calcium-binding protein that is expressed in astrocytes. We compared the kinetics of serum S-100B in left- and right-hemisphere strokes. Data from 38 acute ischaemic stroke patients who had serial serum S-100B measurements during the first 8 days were analyzed. Stroke severity at baseline, as assessed by the National Institutes of Health Stroke Scale (NIHSS), was similar in the two groups. Mean S-100B values were greater in the right-hemisphere stroke group at all time points. Maximum S-100B levels were low in all patients with lower baseline NIHSS scores, and began to rise at a baseline NIHSS score of 16 for right-hemisphere stroke and 20 for left-hemisphere stroke. S-100B levels were significantly correlated with language in left-hemisphere stroke and with neglect in right-hemisphere stroke. These results are consistent with previous clinical/radiological findings, suggesting that serum S-100B is brain-specific and reflects the extent of brain injury in acute ischaemic stroke.

Inhibition of neutrophil elastase attenuates gut mucosal injury evoked by acute alveolar hypoxia in rabbits.

The aim of the present study was to examine whether neutrophil and its elastase activity played consequential roles in the progression of gut barrier dysfunction during acute alveolar hypoxia by using a specific neutrophil elastase inhibitor, sivelestat. With our institutional approval, 20 male rabbits (weight, 2.0-2.5 kg) were randomly allocated into two groups: control (n = 11) or sivelestat group (n = 9; bolus, 10 mg/kg, followed by 10 mg/kg per hour). At 4 h of alveolar hypoxia exposure (fraction of inspired oxygen, 0.10) under mechanical ventilation, the white blood cell counts and their function to produce oxygen radicals were measured. Intestinal permeability and myeloperoxidase activity were also assessed concurrently with the examination of histological changes of gut mucosa. The examination of sham animals (n = 4) exposed to normoxia was performed under the same study protocol. The circulating leukocyte counts and the neutrophil chemiluminescence were not different between the groups, whereas the neutrophil elastase activity was significantly increased in the control but not in the sivelestat and sham groups. Permeability, leukocyte accumulation, and myeloperoxidase activity of ileal wall in the control group were significantly elevated, accompanied by apparent destruction of gut mucosa compared with the sivelestat group (P < 0.05). Despite no significant differences in systemic inflammatory responses, the neutrophil elastase activity is a key element in the progression of functional and structural injury of gut mucosa during acute alveolar hypoxia.

Pharmacokinetics of arundic acid, an astrocyte modulating agent, in acute ischemic stroke.

Arundic acid is an astrocyte modulating agent that improves neurological outcome in experimental acute stroke models. The pharmacokinetics of arundic acid in patients with acute ischemic stroke was investigated in a randomized, double-blind study. Six groups of 8 to 9 patients each received 2, 4, 6, 8, 10, or 12 mg/kg/h of arundic acid for a daily 1-hour infusion until completion of 7 doses. Maximum plasma concentrations of arundic acid increased with increasing dose; however, the systemic exposure was less than dose proportional at higher doses. The mean terminal half-life was approximately 2 to 3 hours. There was no excessive accumulation in plasma. Although systemic exposure in elderly patients was 30% greater than that in younger patients, the plasma concentration returned to nearly or below the limit of quantification prior to next administration. The pharmacokinetics of arundic acid in acute stroke patients assessed in this study were similar to that in healthy adults.

Safety and tolerability of arundic acid in acute ischemic stroke.

Arundic acid (AA; ONO-2506), a novel modulator of astrocyte activation, may improve neuronal survival after stroke. We conducted a multicenter, dose-escalating, randomized, double-blind Phase I trial of AA in acute ischemic stroke. Subjects were randomized to treatment with AA or placebo in sequential dose tiers of 2-12 mg/kg/h (10-16 patients/group) within 24 h of stroke onset. Study drug was infused for 1 h daily over 7 days, and follow-up terminated at 40 days. Neurological and functional outcomes were evaluated through Day 40 as exploratory endpoints. A total of 92 subjects were enrolled with no dose-related pattern of serious adverse events (AEs). Premature terminations caused by AEs occurred in four (8.2%) patients treated with AA and five (11.6%) treated with placebo. Two subjects treated with AA (4.1%) and four given placebo (9.3%) died. Exploratory efficacy analysis showed a trend toward improvement in the change from baseline National Institutes of Health Stroke Scale (NIHSS) in the 8 mg/kg/h AA group on Days 3 (p=0.023 vs. placebo), 7 (p=0.002), 10 (p=0.003), and 40 (p=0.018). A dose of 8 mg/kg/h AA produced a favorable trend in reduction of NIHSS that should be confirmed in a future clinical trial.

Effect of arundic acid on serum S-100beta in ischemic stroke.

We prospectively examined the effect of arundic acid (AA; ONO-2506) on S-100beta, an astrocyte-derived protein, in a phase I acute stroke study. Subjects with acute ischemic stroke were randomized to daily infusion of AA or placebo for 7 days. Serum S-100beta levels were assayed pre-infusion on Days 1-7 and post-infusion on Days 1, 3, and 7, and correlated with National Institutes of Health Stroke Scale (NIHSS). Samples were obtained from 86 subjects (46 AA, 40 placebo). Increase in S-100beta protein level from baseline was less in the AA cohort than in the placebo cohort at 7 (p=0.0471; t-test) and 12 (p=0.0095)-hours post-infusion on Day 3. Baseline NIHSS correlated with maximal S-100beta levels between Days 1 and 3 in the AA (r=0.51; p=0.0003) and placebo (r=0.41; p=0.0084) cohorts and in the pooled aggregate (n=86; r=0.46; p<0.0001). The same correlations were observed between Day 10 NIHSS and Day 1-3 maximum serum S-100beta levels. Treatment with AA was associated with lower serum levels of S-100beta after acute ischemic stroke. Our results showing correlation between S-100beta and NIHSS indicate that this protein is a clinically relevant marker of neurological deficit in acute stroke.

Contribution of high-mobility group box-1 to the development of ventilator-induced lung injury.

RATIONALE: Proinflammatory cytokines play an important role in ventilator-induced lung injury (VILI). High-mobility group box-1 (HMGB1) is a macrophage-derived proinflammatory cytokine that can cause lung injury. OBJECTIVES: This study tested the hypothesis that HMGB1 is released in intact lungs ventilated with large Vt. A second objective was to identify the source of HMGB1. A third objective was to examine the effects of blocking HMGB1 on the subsequent development of VILI. METHODS: Bronchoalveolar lavage fluid (BALF) and lung tissues were obtained from rabbits mechanically ventilated for 4 h with a small (8 ml/kg) versus a large (30 ml/kg) Vt. BALF was also obtained from rabbits with intratracheal instillation of anti-HMGB1 antibody before the initiation of large Vt ventilation. MEASUREMENTS AND MAIN RESULTS: The concentrations of HMGB1 in BALF were fivefold higher in the large than in the small Vt group. Immunohistochemistry and immunofluorescence studies revealed expression of HMGB1 in the cytoplasm of macrophages and neutrophils in lungs ventilated with large Vt. Blocking HMGB1 improved oxygenation, limited microvascular permeability and neutrophil influx into the alveolar lumen, and decreased concentrations of tumor necrosis factor-alpha in BALF. CONCLUSIONS: These observations suggest that HMGB1 could be one of the deteriorating factors in the development of VILI.