|Year : 2015 | Volume
| Issue : 4 | Page : 274-278
Serum matrix metalloproteinase-9 in acute ischemic stroke and its relation to stroke severity
Maged Abdelnaseer1, Nervana Elfayomi1, Eman Hassan MD 1, Manal Kamal2, Ahmed Hamdy3, Enji Elsawy1
1 Department of Neurology, Cairo University, Cairo, Egypt
2 Department of Clinical and Chemical Pathology, Cairo University, Cairo, Egypt
3 Department of Internal Medicine, Cairo University, Cairo, Egypt
|Date of Submission||30-Jun-2015|
|Date of Acceptance||19-Jul-2015|
|Date of Web Publication||27-Nov-2015|
Department of Neurology, Cairo University, 11562 Cairo
Source of Support: None, Conflict of Interest: None
Thrombolytic therapy is currently the only FDA-approved treatment for acute ischemic stroke. Hence, early diagnosis and risk stratification is of great importance in management.
The aim of this work was to study serum level of matrix metalloproteinase-9 (MMP-9) within 24 h of acute ischemic stroke onset and its relation with clinical severity.
Patients and methods
Thirty patients with acute ischemic stroke were subjected to measurement of serum MMP-9 within 24 h of stroke onset and clinical assessment of stroke severity. Thirty healthy volunteers of matched age and sex were included as controls.
Fifteen male and 15 female patients with a mean age of 61 ± 7.11 years were studied. The mean National Institutes of Health Stroke Scale (NIHSS) score on admission was 11.17 ± 4.76. The mean serum level of MMP-9 in patients was 998.8 ± 154.72 ng/ml, which was significantly higher compared with the serum level of MMP-9 in controls (P = 0.003). The mean NIHSS of patients with normal serum level of MMP-9 was less than the mean NIHSS in patients with high MMP-9 serum levels (P = 0.003). There was a significant positive correlation between serum level of MMP-9 and NIHSS score (r = 0.5; P = 0.005) even after adjustment of other variables )age, sex, diabetes, hypertension, fasting blood sugar, uric acid, serum triglycerides, serum cholesterol, and right and left carotid intima media thickness( (r = 0.48; P = 0.032).
Serum MMP-9 level was found to be high in acute ischemic stroke patients and correlated with clinical stroke severity.
Keywords: acute stroke, matrix metalloproteinase-9, NIHSS, stroke severity
|How to cite this article:|
Abdelnaseer M, Elfayomi N, Hassan E, Kamal M, Hamdy A, Elsawy E. Serum matrix metalloproteinase-9 in acute ischemic stroke and its relation to stroke severity. Egypt J Neurol Psychiatry Neurosurg 2015;52:274-8
|How to cite this URL:|
Abdelnaseer M, Elfayomi N, Hassan E, Kamal M, Hamdy A, Elsawy E. Serum matrix metalloproteinase-9 in acute ischemic stroke and its relation to stroke severity. Egypt J Neurol Psychiatry Neurosurg [serial online] 2015 [cited 2021 Mar 3];52:274-8. Available from: http://www.ejnpn.eg.net/text.asp?2015/52/4/274/170661
| Introduction|| |
Stroke represents a leading cause of long-term disability and death  . Tissue plasminogen activator is the only FDA-approved pharmacological treatment for acute ischemic stroke so far, and must be administered within a short therapeutic window from symptom onset. Diagnostic uncertainty is probably one important limitation to tissue plasminogen activator administration during therapeutic window , . Even when presenting outside the window for fibrinolysis, early diagnosis is needed for early management decisions that influence clinical outcome. The rapidly performed noncontrasted head computed tomography (CT) is insensitive for acute ischemic stroke. Multimodal imaging techniques and MRI-based techniques add diagnostic information but are not widely available and require a more advanced interpretation. These show the importance of developing blood-borne biochemical markers to help in the diagnosis of acute ischemic stroke. Currently, no single biomarker has been shown to be clinically applicable as a standalone diagnostic test. Developing such markers, when integrated with other clinical and radiographic information, could facilitate early management decisions ,,,, .
Matrix metalloproteinases (MMPs) belong to a family of proteases  . They modulate many central nervous system developmental and regenerative processes  . MMP-9 are involved in the breakdown of extracellular matrix during tissue remodeling. During stroke, it attacks the extracellular matrix around the blood vessels and neurons, facilitating neural cell death  . MMPs disrupt the blood-brain barrier in the early phase following cerebral ischemia, leading to leakage, leukocyte infiltration, brain edema, and hemorrhage  . MMP-9 promoter region may be a susceptibility locus for stroke  . Its expression is upregulated after cerebral ischemia , , and contributes to infarct extent, and blood-brain barrier breakdown  . Investigation on the relation between MMP-9 and stroke is gaining much interest as it is involved in stroke pathophysiology and its inhibition is of potential therapeutic role  . MMP-9 is a promising marker of ischemic stroke  .
The aim of this study was to investigate serum level of MMP-9 in acute ischemic stroke and its relation with stroke severity.
| Patients and methods|| |
This case-control study was conducted on 30 patients (15 male and 15 female) with acute ischemic stroke within 24 h from stroke onset. Their mean age was 61 ± 7.11 years. Thirty normal volunteers of matched age (mean age: 63 ± 6.78 years) and sex (16 females) served as controls. There was no significant difference between the patient and control groups as regards diabetes, hypertension, and serum levels of uric acid and cholesterol. They were recruited from the Neurology Inpatient Ward, Neurology Outpatient Clinic, and Internal Medicine Department of Kasr Al Aini Teaching Hospital (Cairo, Egypt). Thirty healthy volunteers of matched age and sex were included as controls. We previously studied infarction size and hemorrhagic transformation in relation to MMP-9 in same population . All participants provided informed consent. The study was approved by the local ethics committee, in accordance with the Declaration of Helsinki, and all patients signed informed consent before inclusion.
Patients were selected according to the following inclusion criteria: Age ≥ 45 years, patient presented within 24 hours from stroke onset. Stroke was defined, according to the WHO definition, as 'rapidly developing clinical signs of focal (or global) disturbance of cerebral function, lasting more than 24 h or leading to death, with no apparent cause other than that of vascular origin'  . The time of onset of the stroke was defined as the time when the patient or observer first became aware of the symptoms, or the last time the patient was symptom free (if the patient was conscious after stroke). Exclusion criteria were as follows: hemorrhagic stroke; having severe systemic illness eg; chronic renal failure, hepatic failure, malignancy or any other medical conditions that can increase MMP-9 level (e.g. congestive heart failure)  , and a history of regular intake of drugs, which may affect MMP-9 level (e.g. tetracycline derivatives such as minocycline or doxicyclin  , NSAIDs  , or statins such as atorvastatin or pravastatin  ). MMPs are involved in the arterial remodeling in hypertension and atherosclerosis  . Patients with any arterial disease causing stroke other than atherosclerosis were excluded. Patients were subjected to cardiological examination, ECG, and transthoracic echocardiography to exclude patients with cardioembolic causes of stroke; patients with recent myocardial infarction were also excluded  .
Patients were subjected to thorough medical and neurological examination. Stroke severity was evaluated using the National Institutes of Health Stroke Scale  . The assessment was carried out within 24 h of stroke onset. Stroke severity was categorized on the basis of NIHSS score as mild (0-5), moderate (6-13), or severe (≥14), as described by Bruno et al.  . Laboratory investigation included fasting blood sugar (FBS), kidney and liver function tests, and other laboratory investigations to rule out other severe medical illness, serum uric acid, and serum total cholesterol and triglycerides. Assessment of serum MMP-9 was carried out using ELISA. Samples were collected from patients in a fasting state during the first 24 h of stroke onset and then centrifuged and frozen at temprature below −20°C until assay (maximum 3 months). The kit was purshased from R&D Systems Inc. (Minneapolis, Minnesota, USA). The samples were 100-fold diluted into calibrator diluent RD5-10. As the samples were diluted, the concentration read from the standard curve was multiplied by dilution factor (normal range of serum MMP-9 of 169-705 ng/ml according to manufacaturer). Patients were divided into two groups: the group with normal serum level and the group with high MMP-9 serum level. Criteria of both groups were compared.
Brain CT was performed for all patients in the radiology department of New Kasr Al Aini Hospital using General Electric (GE) Light Speed VCT (GE Healthcare. 4380 Brockton Dr SE, Kentwood, MI 49512, USA). Axial CT cuts were performed with patients in the supine position with 15-20° tilt with 1 cm slice thickness, in addition to posterior fossa cuts every 0.5 cm. MRI was performed when further needed. Size of infarction was determined by the largest diameter of the lesion, according to the method of Pan et al.  . All patients were subjected to B-mode and color-coded duplex sonography of the extracranial vessels (carotid and vertebral arteries) using Phillips HDI 5000 (Phillips, 45-47 Brook St, London, W1K 4HN, England) ultrasound equipment. Extracranial vessels were evaluated with real-time imaging using a linear 10 MHz transducer. Examination was carried out with B-mode transverse scanning of the vessels so as to examine the arterial wall morphology and detect intima media changes. Subsequently, longitudinal scanning and quantification of the intima media thickness (IMT) at the distal far wall of the common carotid artery were carried out as a measure of cerebral atherosclerosis. The control group was subjected to thorough medical examination and the same laboratory investigations performed for the patient group.
Data were expressed as range, mean ± SD, median, frequencies (number of cases), or relative frequencies (%). Results were tabulated and statistically analyzed using personal IBM (http://www-01.ibm.com/software/) computer and statistical package SPSS (SPSS Inc., Released 2007, SPSS for Windows, Version 16.0, Chicago, USA). The unpaired Student T-test was used for comparison between two groups of quantitative variables. The χ2 -test was used for comparison between two groups of categorical data or frequency of events. Spearman's correlation coefficient (r) was used to correlate between MMP-9 level, clinical variables, and radiological findings. The post-hoc test was used for comparison of subgroups. Multivariate analysis was used for comparison between MMP-9 and scores of clinical assessment scales with adjusting confounding factors. The difference between parameters was considered statistically nonsignificant at P value 0.05 or greater, statistically significant at P value 0.05 or less, and statistically highly significant at P value 0.001 or less.
| Results|| |
Patients' NIHSS score ranged from 4 to 20. Five (16.67%) patients had mild degree of initial severity, 14 (46.67%) had moderate degree, and 11 (36.67%) had severe stroke. CT in all patients showed ischemic infarctions either on admission or on follow-up brain imaging.
The mean serum level of MMP-9 in patients was significantly higher than that in controls (P = 0.003). There was no significant difference between the two groups as regards age, sex, diabetes, hypertension, ischemic heart disease, FBS, serum uric acid, and serum cholesterol and triglycerides. There was no significant difference between male and female participants in both the patient and the control group as regards the serum level of MMP-9 (P = 0.274 and 0.076, respectively). [Table 1] shows clinical, laboratory, and imaging findings in the study population.
|Table 1 The clinical, imaging, and laboratory findings in stroke patients |
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The mean NIHSS of patients with normal MMP-9 serum level was less than the mean NIHSS of patients with high MMP-9 serum level (P = 0.003). There was a significant difference between MMP-9 serum levels in patients with mild stroke compared with those with severe stroke (P = 0.021) but not between either of these groups and patients with moderate stroke. There was no significant difference between patients with normal MMP-9 and patients with high MMP-9 as regards age (P = 0.980), history of hypertension (P = 0.239), smoking (P = 0.079), diabetes mellitus (P = 0.326), hyperuricemia (P = 0.985), or ischemic heart disease (P = 0.633). On comparing patients with mild, moderate, and severe stroke, statistically significant differences were seen in MMP-9 serum levels (P = 0.019). These three groups did not show statistically significant difference as regards age, sex, diabetes, hypertension, ischemic heart disease, smoking, FBS, serum uric acid, serum triglycerides, serum cholesterol, right or left IMT or infarct side or site ([Table 2]).
|Table 2 Distribution of clinical and laboratory variables according to stroke severity |
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There was a statistically significant positive correlation between serum level of MMP-9 and initial stroke severity as measured with NIHSS score (P = 0.005; [Figure 1]). This correlation remained significant after adjustment for age, sex, diabetes, hypertension, FBS, uric acid, serum triglycerides, serum cholesterol, and right and left carotid IMT (r = 0.48; P = 0.032). There was no significant correlation between age of the patients and serum MMP-9 level (P = 0.929).
|Figure 1 Correlation between MMP9 serum level and size of cerebral infarction in stroke patients|
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| Discussion|| |
While being the second leading cause of death worldwide, stroke is also a leading cause of significant disability  . MMP-9 activity was found to be markedly elevated in the infarcted human cerebral tissue 2 days after infarction  . This was followed by a study conducted by Heo et al.  showing that MMP-9 increases transiently 2 h after stroke in nonhuman primates. In the present study, MMP-9 level was significantly higher in acute ischemic stroke compared with controls. This supports the notion that MMP-9 can be a potential biomarker for focal cerebral ischemia in acute stage  . This is in accordance with the study by Heo et al.  , who found that MMP-9 serum level on admission was significantly higher in stroke patients compared with the control group. Reynolds et al.  also demonstrated the diagnostic utility of MMP-9 level measured 12 h after symptom onset, as it was significantly higher in patients compared with controls. Lynch et al.  also confirmed the possible role of MMP-9 as a marker of acute stroke.
The NIHSS quantifies impairment throughout the expected range of stroke severity  . In the present study, there was an association between higher serum levels of MMP-9 and more severe stroke even after adjustment for sex, age, diabetes, hypertension, FBS, serum uric acid, serum triglycerides, serum cholesterol, and carotid IMT. These support the role of MMP-9 as an independent predictor of clinical severity of ischemic stroke in the acute stage. These results are in agreement with those of Demir et al  and Montaner et al.  . These data may reflect that MMP-9 may have a deleterious effect on stroke patients in the acute stage. It is involved in neurotoxicity and blood-brain barrier disruption in the acute phase of cerebrovascular stroke  .
In a study by Fortunato et al.  , there was a racial difference in MMP-9 serum level elevation following immune stimulation between African and white American populations. Recently, another study also showed interethnic genetic variation of MMP-9. This study acknowledged the importance of determining population variability of MMP-9 in different geographical locations  . There is a paucity of information on MMP-9 rise after acute ischemic stroke, and its possible role as a marker of acute ischemic stroke, in African and Arabic populations. The current study was conducted on a sample of Egyptian population, and it supports the notion that MMP-9 is elevated early after ischemic stroke onset and can be a predictor of clinical severity in patients not receiving thrombolytic therapy.
| Conclusion|| |
Serum MMP-9 level was found to be high on the first day after acute ischemic stroke. There is a positive correlation between serum level of MMP-9 on first day after acute ischemic stroke and its clinical severity.
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Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2]
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