Assessment of Acute Phase Proteins in Acute Ischemic Stroke

Which one predicts mortality better in acute ischemic stroke: negative vs positive acute-phase reactants

AIM

The aim of the study is to investigate the relationship between negative acute-phase reactants and positive acute-phase reactants with in-hospital mortality in patients diagnosed with acute ischemic stroke (AIS) in the emergency department (ED).

METHODS AND MATERIALS

Patients aged 18 and older who presented to the ED of a tertiary hospital with AIS were included in the study. Demographic and clinical characteristics, laboratory parameters, acute-phase reactants, National Institutes of Health Stroke Scale (NIHSS), and outcome data of the included patients were recorded on a standard data form.

RESULTS

A total of 588 patients were included in the study. When the in-hospital mortality of patients was examined, the mortality rate was 17.7%. In the analysis for predicting mortality, it was determined that albumin had the highest predictive power between the area under the curve (AUC) and the determined predictive values (AUC: 0.759, 95% CI 0.707-0.810, p < 0.001). The analyses of the study data revealed that albumin (<0.001) and TF (p = 0.049), which are negative acute-phase reactants, were independent predictors of mortality. According to our study data, in patients with AIS, for each unit decrease in albumin level at the time of ED admission, the risk of mortality increased by 0.868 times, and for each unit decrease in TF level, the risk of mortality increased by 0.593 times.

CONCLUSION

According to the study data, albumin and TF levels, which are negative acute-phase reactants, are independent determinants of in-hospital mortality in patients with acute ischemic stroke in the emergency department.

Chrysin inhibits ferroptosis of cerebral ischemia/reperfusion injury via regulating HIF-1α/CP loop

Chrysin is a natural flavonoid with powerful neuroprotective capacity. Cerebral ischemia/reperfusion injury (CIRI) is associated with oxidative stress and ferroptosis. Hypoxia-inducible factor 1α (HIF-1α) and ceruloplasmin (CP) are the critical targets for oxidation reactions and iron transport. But the regulatory mechanism between them is still unclear. Transient middle cerebral artery occlusion (tMCAO) model in rats and oxygen and glucose deprivation/re-oxygenation (OGD/R) model in PC12 cells were applied. Pathological tissue staining and biochemical kit were used to evaluate the effect of chrysin. The relationship between HIF-1α and CP was verified by transcriptomics, qRT-PCR and Western blot. In CIRI, HIF-1α/CP loop was discovered to be the regulatory pathway of ferroptosis. CIRI led to activation and nuclear translocation of HIF-1α, which promoted CP transcription and translation, and downstream ferroptosis. Inhibition of HIF-1α had opposite effect on CP and ferroptosis regulation. Overexpression of CP increased the expression of HIF-1α, nevertheless, inhibited the nuclear translocation of HIF-1α and alleviated CIRI. Silencing CP promoted HIF-1α elevation in nucleus and aggravated CIRI. Mechanistically, chrysin restrained HIF-1α nuclear translocation, thereby inhibiting CP transcription and translation, which in turn reduced downstream HIF-1α expression and mitigated ferroptosis in CIRI. Our results highlight chrysin restrains ferroptosis in CIRI through HIF-1α/CP loop.

Extracellular vesicles: a new communication paradigm of complement in neurological diseases

The complement system is crucial to the innate immune system. It has the function of destroying pathogens by activating the classical, alternative, and lectin pathways. The complement system is important in nervous system diseases such as cerebrovascular and neurodegenerative diseases. Activation of the complement system involves a series of intercellular signaling and cascade reactions. However, research on the source and transport mechanisms of the complement system in neurological diseases is still in its infancy. Studies have increasingly found that extracellular vesicles (EVs), a classic intercellular communication paradigm, may play a role in complement signaling disorders. Here, we systematically review the EV-mediated activation of complement pathways in different neurological diseases. We also discuss the prospect of EVs as future immunotherapy targets.

Multi-omics research strategies in ischemic stroke: A multidimensional perspective

Ischemic stroke (IS) is a multifactorial and heterogeneous neurological disorder with high rate of death and long-term impairment. Despite years of studies, there are still no stroke biomarkers for clinical practice, and the molecular mechanisms of stroke remain largely unclear. The high-throughput omics approach provides new avenues for discovering biomarkers of IS and explaining its pathological mechanisms. However, single-omics approaches only provide a limited understanding of the biological pathways of diseases. The integration of multiple omics data means the simultaneous analysis of thousands of genes, RNAs, proteins and metabolites, revealing networks of interactions between multiple molecular levels. Integrated analysis of multi-omics approaches will provide helpful insights into stroke pathogenesis, therapeutic target identification and biomarker discovery. Here, we consider advances in genomics, transcriptomics, proteomics and metabolomics and outline their use in discovering the biomarkers and pathological mechanisms of IS. We then delineate strategies for achieving integration at the multi-omics level and discuss how integrative omics and systems biology can contribute to our understanding and management of IS.

Circulating Biomarkers in Long-Term Stroke Prognosis: A Scoping Review Focusing on the South African Setting

Cerebrovascular disease, including both ischaemic and haemorrhagic strokes, remains one of the highest causes of global morbidity and mortality. Developing nations, such as South Africa (SA), are affected disproportionately. Early identification of stroke patients at risk of poor clinical prognosis may result in improved outcomes. In addition to conventional neuroimaging, the role of predictive biomarkers has been shown to be important. Little data exist on their applicability within SA. This scoping review aimed to evaluate the currently available data pertaining to blood biomarkers that aid in the long-term prognostication of patients following stroke and its potential application in the South African setting. This scoping review followed a 6-stage process to identify and critically review currently available literature pertaining to prognostic biomarkers in stroke. An initial 1191 articles were identified and, following rigorous review, 41 articles were included for the purposes of the scoping review. A number of potential biomarkers were identified and grouped according to the function or origin of the marker. Although most biomarkers showed great prognostic potential, the cost and availability will likely limit their application within SA. The burden of stroke is increasing worldwide and appears to be affecting developing countries disproportionately. Access to neuroradiological services is not readily available in all settings and the addition of biomarkers to assist in the long-term prognostication of patients following a stroke can be of great clinical value. The cost and availability of many of the reviewed biomarkers will likely hinder their use in the South African setting.

Elevated Serum Inflammatory Markers in Subacute Stroke Are Associated With Clinical Outcome but Not Modified by Aerobic Fitness Training: Results of the Randomized Controlled PHYS-STROKE Trial

Background: Inflammatory markers, such as C-reactive Protein (CRP), Interleukin-6 (IL-6), tumor necrosis factor (TNF)-alpha and fibrinogen, are upregulated following acute stroke. Studies have shown associations of these biomarkers with increased mortality, recurrent vascular risk, and poor functional outcome. It is suggested that physical fitness training may play a role in decreasing long-term inflammatory activity and supports tissue recovery.

Aim: We investigated the dynamics of selected inflammatory markers in the subacute phase following stroke and determined if fluctuations are associated with functional recovery up to 6 months. Further, we examined whether exposure to aerobic physical fitness training in the subacute phase influenced serum inflammatory markers over time.

Methods: This is an exploratory analysis of patients enrolled in the multicenter randomized-controlled PHYS-STROKE trial. Patients within 45 days of stroke onset were randomized to receive either four weeks of aerobic physical fitness training or relaxation sessions. Generalized estimating equation models were used to investigate the dynamics of inflammatory markers and the associations of exposure to fitness training with serum inflammatory markers over time. Multiple logistic regression models were used to explore associations between inflammatory marker levels at baseline and three months after stroke and outcome at 3- or 6-months.

Results: Irrespective of the intervention group, high sensitive CRP (hs-CRP), IL-6, and fibrinogen (but not TNF-alpha) were significantly lower at follow-up visits when compared to baseline (p all ≤ 0.01). In our cohort, exposure to aerobic physical fitness training did not influence levels of inflammatory markers over time. In multivariate logistic regression analyses, increased baseline IL-6 and fibrinogen levels were inversely associated with worse outcome at 3 and 6 months. Increased levels of hs-CRP at 3 months after stroke were associated with impaired outcome at 6 months. We found no independent associations of TNF-alpha levels with investigated outcome parameters.

Conclusion: Serum markers of inflammation were elevated after stroke and decreased within 6 months. In our cohort, exposure to aerobic physical fitness training did not modify the dynamics of inflammatory markers over time. Elevated IL-6 and fibrinogen levels in early subacute stroke were associated with worse outcome up to 6-months after stroke.

Clinical Trial Registration:ClinicalTrials.gov, NCT01953549.

Elevated plasma biomarkers of inflammation in acute ischemic stroke patients with underlying dementia

BACKGROUND

The blood-brain barrier has been a hindrance to developing blood-based diagnostic tests for dementias, as it limits the appearance of brain biomarkers in the blood. Our aim was to see if the natural opening of the blood-brain barrier induced by ischemic stroke would increase serum levels of inflammatory biomarkers known to be elevated in the brains of patients with Alzheimer's disease and other neurodegenerative dementias.

METHODS

Forty-three patients with acute ischemic stroke presenting to Stony Brook University Hospital were prospectively enrolled in the study. Eight of these patients were clinically diagnosed as having an underlying neurodegenerative dementia. Blood was drawn acutely within 72 h of stroke symptom onset, and serum levels of the classic inflammatory biomarkers, interleukin-6 (IL-6) and C-reactive protein (CRP) were measured, along with levels of S100B protein (S100B) and complement C3 (CC3).

RESULTS

Serum levels of IL-6 and CRP in patients with acute ischemic stroke and underlying dementia (AIS + D) were significantly higher (p = 0.002 and 0.003, respectively) than in patients with acute ischemic stroke alone (AIS). Serum levels of S100B and CC3 did not differ significantly between the groups.

CONCLUSIONS

This study supports the possibility that opening of the blood-brain barrier may enhance the blood appearance of brain tissue markers of inflammation associated with neurodegenerative dementia. Further study is warranted to test this possibility, given the recent emergence of methods to open the blood-brain barrier for diagnostic or therapeutic purposes.

Establishing molecular signatures of stroke focusing on omic approaches: a narrative review

Stroke or 'brain attack' is considered to be the major cause of mortality and morbidity worldwide after myocardial infraction. Inspite of the years of research and clinical practice, the pathogenesis of stroke still remains incompletely understood. Omics approaches not only enable the description of a huge number of molecular platforms but also have a potential to recognize new factors associated with various complex disorders including stroke. The most significant development among all other omics technologies over the recent years has been seen by genomics which is a powerful tool for exploring the genetic architecture of stroke. Genomics has decisively established itself in stroke research and by now wealth of data has been generated providing new insights into the physiology and pathophysiology of stroke. However, the efficacy of genomic data is restricted to risk prediction only. Omics approaches not only enable the description of a huge number of molecular platforms but also have a potential to recognize new factors associated with various complex disorders including stroke. The data generated by omics technologies enables clinicians to provide detailed insight into the makeup of stroke in individual patients, which will further help in developing diagnostic procedures to direct therapies. Present review has been compiled with an aim to understand the potential of integrated omics approach to help in characterization of mechanisms leading to stroke, to predict the patient risk of getting stroke by analyzing signature biomarkers and to develop targeted therapeutic strategies.

Dynamics of inflammatory factors expression in ischemic brain tissue injury

Ischemic stroke is one of the most common cause of mortality and disability in the modern world. Still, therapeutic options remain modest. Aim of the study was to present dynamics of inflammatory factors expression (C reactive protein, procalcitonin, interleukin 10) in patients after ischemic stroke. Our study included 101 patients divided in thrombolised and nonthrombolised groups. Inflammatory factors concentration in serum was determinate at admission, 24, 48 hours and seven days after the initial onset, while neurological assessment was measured at the admission, 24 hours, seven days and three months after the initial onset using National Institute of Health Stroke Scale and Rankin Scale. Certain pattern was observed in dynamics of inflammatory factors: intensive increase in first and second day after the stroke, followed by decrease till day seven in both groups. Additionally, thrombolised group showed significant neurological improvement. Although well investigated, the role of inflammatory factors in the ischemic stroke still stays controversial. High association of C reactive protein and interleukin 10 values suggest potential prognostic role in patient’s follow-up, while the role of procalcitonin values still remains unclear.

Significance of Complement System in Ischemic Stroke: A Comprehensive Review

The complement system is an essential part of innate immunity, typically conferring protection via eliminating pathogens and accumulating debris. However, the defensive function of the complement system can exacerbate immune, inflammatory, and degenerative responses in various pathological conditions. Cumulative evidence indicates that the complement system plays a critical role in the pathogenesis of ischemic brain injury, as the depletion of certain complement components or the inhibition of complement activation could reduce ischemic brain injury. Although multiple candidates modulating or inhibiting complement activation show massive potential for the treatment of ischemic stroke, the clinical availability of complement inhibitors remains limited. The complement system is also involved in neural plasticity and neurogenesis during cerebral ischemia. Thus, unexpected side effects could be induced if the systemic complement system is inhibited. In this review, we highlighted the recent concepts and discoveries of the roles of different kinds of complement components, such as C3a, C5a, and their receptors, in both normal brain physiology and the pathophysiology of brain ischemia. In addition, we comprehensively reviewed the current development of complement-targeted therapy for ischemic stroke and discussed the challenges of bringing these therapies into the clinic. The design of future experiments was also discussed to better characterize the role of complement in both tissue injury and recovery after cerebral ischemia. More studies are needed to elucidate the molecular and cellular mechanisms of how complement components exert their functions in different stages of ischemic stroke to optimize the intervention of targeting the complement system.

Systemic inflammation as a therapeutic target in acute ischemic stroke

Acute systemic inflammatory reaction superimposed on chronic low-grade inflammation accompanies acute ischemic stroke. Elevated blood levels of systemic inflammatory markers such as IL-6 or C-reactive protein are associated with an unfavorable functional outcome and increased mortality after stroke. Animal studies have demonstrated a causal relationship between systemic inflammation and ischemic brain damage. The mechanisms linking systemic inflammation with poor outcome include increased neutrophil infiltration of cerebral cortex, disruption of the blood-brain barrier, impaired tissue reperfusion, increased platelet activation and microvascular coagulation and complement-dependent brain injury. Non-selective (e.g., by statins) or selective (e.g., by inhibition of IL-6) attenuation of systemic inflammation, enhancement of systemic anti-inflammatory response (e.g., by infusion of IL-1 receptor antagonist), prevention of infections that exacerbate systemic inflammation or inhibition of neuronal pathways triggering inflammatory reaction are potential therapeutic targets in stroke patients. This review discusses the relationship between systemic inflammation, cerebral ischemia and prognosis in the context of therapeutic strategies.

The sustained increase of plasma fibrinogen during ischemic stroke predicts worse outcome independently of baseline fibrinogen level

Hyperfibrinogenemia at the beginning of ischemic stroke is associated with poor outcome. We hypothesized that the sustained increase of plasma fibrinogen during stroke predicts outcome independently of baseline fibrinogen concentration. We included 266 patients with first-ever ischemic stroke in whom plasma fibrinogen level was measured on days 1, 7, and 14. The sustained fibrinogen’s increase was defined as the persistent elevation of fibrinogen’s concentration on days 7 and 14 by at least 20 % compared to the level on day 1. The functional outcome on day 30 was assessed using modified Rankin Scale (mRS). Favorable outcome was defined as mRS 0–1. The sustained increase of fibrinogen was found in 17 % of patients. On multivariate logistic regression analysis adjusted for age, NIHSS score, baseline fibrinogen >2.66 mmol/L, presence of infection, and hyperglycemia, the sustained fibrinogen’s level was associated with reduced chance of favorable outcome (OR: 0.17, 95 % CI: 0.06–0.48, P < 0.01).

Cardioembolic and small vessel disease stroke show differences in associations between systemic C3 levels and outcome

Background

Activation of the complement system has been proposed to play a role in the pathophysiology of stroke. As the specific involvement of the complement proteins may be influenced by stroke etiology, we compared plasma C3 and C3a levels in patients with cardioembolic (CE) and small vessel disease (SVD) subtypes of ischemic stroke and control subjects and evaluated their association to outcome at three months and two years.

Methodology/Principal Findings

Plasma C3 and C3a levels in 79 CE and 79 SVD stroke patients, sampled within 10 days and at three months after stroke, and age- and sex-matched control subjects from The Sahlgrenska Academy Study on Ischemic Stroke were measured by ELISA. Functional outcome was assesed with modified Rankin Scale. In the CE group, plasma C3 levels were elevated only in the acute phase, whereas C3a was elevated at both time points. The follow-up phase plasma C3 levels in the upper third were associated with an increased risk of unfavorable outcome at three months (OR 7.12, CI 1.72–29.46, P = 0.007) as well as after two years (OR 8.25, CI 1.61–42.28, P = 0.011) after stroke. These associations withstand adjustment for age and sex. Conversely, three-month follow-up plasma C3a/C3 level ratios in the middle third were associated with favorable outcome after two years both in the univariate analysis (OR 0.19, CI 0.05–0.82, P = 0.026) and after adjustment for age and sex (OR 0.19, CI 0.04–0.88, P = 0.033). In the SVD group, plasma C3 and C3a levels were elevated at both time points but showed no significant associations with outcome.

Conclusions

Plasma C3 and C3a levels are elevated after CE and SVD stroke but show associations with outcome only in CE stroke.

Hyperfibrinogenemia and functional outcome from acute ischemic stroke

BACKGROUND AND PURPOSE

Epidemiological studies have found strong correlations between elevated plasma fibrinogen levels and both ischemic stroke incidence and stroke mortality. Little is known about the influence of fibrinogen levels on functional stroke outcome.

METHODS

Placebo data from the Stroke Treatment with Ancrod Trial (STAT) and European Stroke Treatment with Ancrod Trial (ESTAT) were analyzed. Fibrinogen levels were determined within 3 hours (STAT) or 6 hours (ESTAT) of stroke onset and at preset intervals throughout 5 days of intravenous infusions. Barthel Index scores at 90 days quantified functional outcomes. The association between initial fibrinogen levels and functional outcomes was evaluated using a multiple logistic regression analysis.

RESULTS

Fibrinogen levels increased gradually over the first 24 hours from a pretreatment median value of 340 mg/dL to a 24-hour median value of 376 mg/dL. In a univariate analysis, the proportion of patients with good functional outcome decreased with increasing quartiles of initial fibrinogen levels in both STAT (36.0% to 26.2%) and ESTAT (53.8% to 24.8%). In a multifactorial analysis, the same trend was observed. Patients with initial fibrinogen levels <450 mg/dL had better outcomes in both studies; the difference (42.0% versus 21.6%) was significant in ESTAT (P=0.0006), even when corrected for age and initial stroke severity.

CONCLUSIONS

The independent association of higher initial fibrinogen levels with poor outcome needs to be verified using a larger acute stroke dataset. Even in the present small populations, the apparent association of these 2 variables suggests that treatments designed to reduce fibrinogen levels could potentially be important in treating acute ischemic stroke.

High-sensitivity C-reactive protein levels in cerebrospinal fluid and serum in severe head injury: Relationship to tumor necrosis factor-α and interleukin-6

Recent studies have demonstrated the role of high-sensitivity C-reactive protein (hsCRP) in inflammatory diseases; however, it is unclear whether this molecule has a role after severe head injury (SHI). Our aim was to evaluate the levels of hsCRP in both cerebrospinal fluid (CSF) and serum from patients after SHI. The study focused on 11 patients with SHI, and evaluated CSF and serum levels of hsCRP, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in a 10-day period following the head trauma. The values were compared with those from nine control patients, who had normal pressure hydrocephalus. In the CSF and serum of the patients after SHI, HsCRP was found to be significantly higher, at all times, than in the controls; TNF-alpha and IL-6 levels were also higher in these patients. However, hsCRP levels did not correlate with either TNF-alpha or IL-6. TNF-alpha and IL-6 increased during the period immediately following the SHI, and intrathecal levels were always higher than those of the serum. This study demonstrates for the first time that hsCRP reaches high levels in both CSF and serum in patients with SHI, and it may therefore be used as an inflammatory index. This finding suggests a need for further studies in this area, which are larger in scope than the present study.

C-reactive protein and fibrinogen in acute stroke patients with and without sleep apnea

BACKGROUND AND PURPOSE

Although sleep apnea (SA) is a risk factor for ischemic stroke and an important prognosticator in affected patients, the exact pathophysiological link between SA and stroke remains to be established. We investigated whether levels of C-reactive protein (CRP) and fibrinogen are increased in patients with acute stroke and SA compared with stroke patients without SA.

PATIENTS AND METHODS

117 consecutive patients with ischemic stroke admitted to our stroke unit within 12 h after stroke onset were included in this study. On admission, CRP and fibrinogen levels were determined. All patients received cardiorespiratory polygraphy during the first 72 h of their hospital stay. In all patients, demographic data, National Institutes of Health Stroke Scale score and cerebrovascular risk factors were assessed.

RESULTS

SA defined by an apnea-hypopnea index (AHI) of > or =10/h was found in 64 (55%) patients. Elevated CRP and fibrinogen levels were seen twice as often in patients with SA than in patients without (CRP: 52 vs. 26%; fibrinogen: 72 vs. 37%). After multivariate logistic regression analysis, an AHI of > or =10/h was independently correlated with raised levels of both of these parameters.

CONCLUSION

SA is independently associated with raised levels of CRP and fibrinogen in patients with acute ischemic stroke. We assume that both proteins are part of the pathophysiological pathway linking SA to stroke.

Elevated Serum Fibrin-Monomer Levels are Associated With High Long-Term Cerebrovascular Event Rates in Acute Ischemic Stroke Patients

BACKGROUND

Serum fibrin-monomer (FM) is a precursor of stable fibrin, and is a sensitive marker of a systemic hypercoagulable state. It has been reported that, in patients with acute ischemic stroke, higher levels of serum FM reflect intracardiac thrombus formation.

METHODS AND RESULTS

Serum coagulation and fibrinolytic activity were measured in 113 patients with acute ischemic stroke within 7 (6+/-1) days after onset. The patients were followed for a mean of 354 (range 36-585) days. The primary endpoints were ischemic stroke recurrence with/without death. FM was markedly higher in the 19 cases with stroke recurrence (49.6+/-53.6 microg/ml) than in the 94 patients without stroke recurrence (14.6+/-30.5 microg/ml; p=0.008). The cerebrovascular event rates were markedly higher in the 12 cases with FM > or =16.5 microg/ml (37.5%) than in the 7 cases with FM <16.5 microg/ml (8.6%; p<0.001). Cox proportional hazards multivariate analysis showed that the FM level was an independent predictor of ischemic stroke recurrence with/without death (hazard ratio, 1.516 per + 1 standard deviation increase; 95% confidence interval, 1.042-2.180; p=0.036).

CONCLUSIONS

Elevated serum FM levels in hospitalized ischemic stroke patients may be associated with a persistent systemic hypercoagulable state and high long-term rates of cerebrovascular events.

Complement-Dependent P-Selectin Expression and Injury following Ischemic Stroke

The mechanisms that contribute to inflammatory damage following ischemic stroke are poorly characterized, but studies indicate a role for both complement and P-selectin. In this study, we show that compared with wild-type mice, C3-deficient mice showed significant improvement in survival, neurological deficit, and infarct size at 24 h after middle cerebral artery occlusion and reperfusion. Furthermore, P-selectin protein expression was undetectable in the cerebral microvasculature of C3-deficient mice following reperfusion, and there was reduced neutrophil influx, reduced microthrombus formation, and increased blood flow postreperfusion in C3-deficient mice. We further investigated the use of a novel complement inhibitory protein in a therapeutic paradigm. Complement receptor 2 (CR2)-Crry inhibits complement activation at the C3 stage and targets to sites of complement activation. Treatment of normal mice with CR2-Crry at 30 min postreperfusion resulted in a similar level of protection to that seen in C3-deficient mice in all of the above-measured parameters. The data demonstrate an important role for complement in cerebrovascular thrombosis, inflammation, and injury following ischemic stroke. P-selectin expression in the cerebrovasculature, which is also implicated in cerebral ischemia and reperfusion injury, was shown to be distal to and dependent on complement activation. Data also show that a CR2-targeted approach of complement inhibition provides appropriate bioavailability in cerebral injury to enable complement inhibition at a dose that does not significantly affect systemic levels of serum complement activity, a potential benefit for stroke patients where immunosuppression would be undesirable due to significantly increased susceptibility to lung infection.

Alterations in plasma complement levels after human ischemic stroke

OBJECTIVE

Stroke is a leading cause of morbidity and mortality in the United States. Recent animal studies have implicated the complement system in cerebral ischemia/reperfusion injury and suggest that complement inhibition may improve stroke outcomes. To assess the applicability of these findings to humans, we evaluated the characteristics and time course of human complement activation after stroke.

METHODS

We compared peripheral blood levels of complement factor 3a (C3a), 5a (C5a), and sC5b-9 drawn from 15 patients on poststroke Days 1, 2, 3, 7, 14, 21, and 28 to age-, race/ethnicity-, and sex-matched controls from the same population. Statistical analysis was performed using unpaired Mann-Whitney nonparametric tests with Bonferroni correction. All data is presented as the mean +/- standard deviation.

RESULTS

Mean C3a concentrations showed significant early elevations in stroke patients relative to matched controls (controls: 1080 +/- 189 ng/ml; Day 1: 1609 +/- 422 ng/ml, P = 0.0008; Day 3: 1520 +/- 317 ng/ml, P = 0.0005; Day 7: 1526 +/- 386 ng/ml, P = 0.001). C3a was also significantly elevated on Day 28 (1448 +/- 386 ng/ml, P = 0.004). Before poststroke Day 7, mean C5a levels did not differ significantly from controls. However, beginning on Day 7 and continuing through Day 14, there were significant elevations in C5a (controls: 3.33 +/- 2.1 ng/ml; day 7: 6.86 +/- 3.5 ng/ml, P = 0.005; Day 14: 7.65 +/- 4.6 ng/ml, P = 0.004). Mean sC5b-9 concentrations showed early depressions that reached significance on Days 1 and 2 (controls: 275.6 +/- 107 ng/ml; Day 1: 167.0 +/- 108 ng/ml, P = 0.006; Day 2: 156.3 +/- 80.0 ng/ml, P = 0.005) and did not differ significantly from controls at any other time point.

CONCLUSION

C3a is acutely elevated after human ischemic stroke, C5a shows delayed elevations 7 to 14 days after cerebral ischemia, and sC5b-9 is acutely depressed after stroke. Together, these data confirm complement activation after stroke and suggest that this activation is a heterogeneous process, with varying responses for different components.

Suppression of angioplasty-related inflammation by pre-procedural treatment with trimetazidine

Percutaneous transluminal coronary angioplasty (PTCA) has been recognized as a reliable treatment procedure for acute reversible ischemia and reperfusion. Ischemic reperfusion cycle in PTCA leads to the systemic inflammation and extensive tissue injury by the production of reactive oxygen species including nitric oxide (NO) radicals. In patients with coronary artery disease, undergoing PTCA, the effects of trimetazidine (TMZ), a piperazine-derivative anti-anginal drug, were studied on several indirect markers of systemic inflammatory response: tumor necrosis factor-alpha (TNF-alpha), C-reactive protein (CRP) and NO products (nitrite and nitrate). Patients (n = 11 each group) were untreated or pre-treated with TMZ (20 mg per orally three times a day), begun three days prior to PTCA, and marker levels were measured before the start of TMZ therapy (baseline), just before PTCA (0 hr), and 4, 24, and 48 hrs after PTCA. The baseline levels of markers were not significantly different between the untreated and pre-treated patients. In contrast, all parameters were lower in the TMZ-treated group than those in the matched control group in the pre- and post-angioplasty periods. Interestingly, in the TMZ group, CRP and nitrite levels were significantly lower than in the control group at each time point of the pre- and post-angioplasty periods, but the TNF-alpha levels were significantly decreased only in the post-angioplasty period. Pre-procedural treatment with oral TMZ for three days significantly suppressed the elevation of inflammatory markers before and shortly after PTCA. We suggest the usefulness of TMZ in preventing inflammatory cardiovascular events after PTCA.

Increased serum malondialdehyde levels in chronic stage of ischemic stroke

Serum lipoperoxidation products such as malondialdehyde (MDA) reflect oxidative stress. There are contradictory results addressing the levels of lipoperoxidation products in chronic phase of ischemic stroke. In the present study, we aimed to determine the serum MDA levels in stroke patients 6 months after the cerebrovascular accident. We also compared serum MDA levels in two major groups of patients with ischemic stroke resulting from small vessel and large vessel diseases, respectively. Serum MDA levels of thirty-eight patients who had ischemic stroke (19 with atherothrombotic ischemic stroke and 19 with lacunar infarction) and 30 healthy volunteers were measured. While there was no significant difference in serum MDA levels between the chronic ischemic stroke subgroups (p = 0.795), the serum MDA levels of patients with atherothrombotic ischemic stroke (p < 0.001) or with lacunar infarction (p < 0.001) were significantly higher compared to the control group. We also demonstrated that serum MDA levels of the patients with and those without hypertension (p = 0.846), diabetes mellitus (p = 0.891), or dyslipidemia (p = 0.38) were not significantly different. In conclusion, serum MDA levels were elevated in chronic stroke patients with small or large vessel diseases. To the best of our knowledge, this is the first report showing that serum MDA levels of these two groups are not significantly different. Furthermore, serum MDA levels do not differ solely by the existence or nonexistence of hypertension, diabetes mellitus or hyperlipidemia.

Association of C-Reactive Protein with the Presence and Extent of Angiographically Verified Coronary Artery Disease

Prospective studies have demonstrated that markers of inflammation, such as high-sensitivity C-reactive protein (hsCRP) and fibrinogen, predict future cardiovascular disease risk. However, the association between the hsCRP and fibrinogen levels and the extent of coronary stenosis in patients with coronary artery disease (CAD) remains controversial. The aim of our case-control study was to assess the association of inflammatory markers with the occurrence and extent of CAD. Serum hsCRP and plasma fibrinogen levels were measured in 138 patients with angiographically assessed CAD and in 183 healthy subjects matched according to age and gender. According to the number of significantly stenosed (>or= 50%) vessels, the patients were classified in four groups: those without stenosis (0-vessel disease) and those with 1, 2 or 3-vessel disease. The hsCRP and fibrinogen levels were significantly higher in patients than in controls (p < 0.001). Although the hsCRP and fibrinogen levels tended to increase with the number of stenotic vessels, the differences were only significant for hsCRP (p < 0.01). Regression analysis indicated hsCRP as an independent predictor for the presence (OR = 3.573, p < 0.05) and extent of CAD (beta = 1.095, p < 0.05). In conclusion, the present study is the first report concerning the frequency distribution of hsCRP in Serbian healthy subjects and CAD patients. We have shown that elevated levels of hsCRP are associated with the presence and extent of CAD.