Association of ALOX5AP with ischemic stroke in eastern Chinese

Association of 5-lipoxygenase activating protein gene polymorphism and stroke: A study from north east of Iran

Background: Stroke is a multifactorial disorder and a major cause of morbidity and mortality around the world. There are growing numbers of candidate gene pathways which are thought to be associated with stroke. Genes involved in lipid metabolism are important issues in stroke studies. Studying different polymorphisms in these genes are becoming an interest for researchers. 5-lipoxygenase activating protein (ALOX5AP) is one of these genes. Different studies have provided different relations between ALOX5AP promoter polymorphism (rs17222919) and stroke. In the present study, we have evaluated this gene polymorphism in a population in north east of Iran. Methods: This case-control study took place in Ghaem Hospital, Mashhad, Iran. Patients with computed tomography (CT) or magnetic resonance imaging (MRI) confirmation for ischemic stroke were enrolled in this study and considered as case group. Healthy persons without ischemic stroke were control group. During 1-year period of this study, ALOX5AP gene polymorphism in 200 healthy patients (control group) as well as 228 patients with stroke (case group) was evaluated by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: All of 428 persons (228 cases and 200 healthy controls) enrolled in this study. The genotype and allele frequency was significantly different between both groups (P = 0.001 and P = 0.003, respectively). A total number of 54 patients had G allele in case group in contrast to 27 ones in control group. Also, 174 patients in case group had T allele and 173 persons had this allele in control group. In compression of TT genotype, the risk of developing stroke in GG and TG genotypes increased by 3.998 and 1.643, respectively. Also the risk of ischemic stroke with G allele would increase by 2.128. Conclusion: According to our results, ALOX5AP promoter polymorphism (rs17222919) is related to increased ischemic stroke in Iranian population.

Lack of association between ALOX5AP genetic polymorphisms and risk of ischemic stroke: evidence from meta-analyses

BACKGROUND

In recent years, there has been substantial research evaluating the relationship between arachidonate 5-lipoxygenase-activating protein (ALOX5AP) polymorphisms and ischemic stroke (IS). The objective of this study was to systematically review and analyze the existing evidence.

METHODS

A comprehensive search of major electronic databases for studies published between 1990 and 2018 was carried out. Data were synthesized as OR and 95% CI using fixed-effects and random-effects models.

RESULTS

A total of 30 studies were available for analysis. The aggregate sample size across all studies was 32,782 (16,294 cases and 16,488 controls). We found no association of the ALOX5AP rs10507391 (OR=1.03 for A allele vs T allele; 95% CI: 0.93-1.14; P=0.557), rs4769874 (OR=1.13 for A allele vs G allele; 95% CI: 1.00-1.28; P=0.050), rs9551963 (OR=1.03 for A allele vs C allele; 95% CI: 0.96-1.11; P=0.372), rs17222814 (OR=1.09 for A allele vs G allele; 95% CI: 0.96-1.24; P=0.195), rs17222919 (OR=0.89 for G allele vs T allele; 95% CI: 0.75-1.06; P=0.175), and rs4073259 (OR=1.20 for A allele vs G allele; 95% CI: 1.00-1.45; P=0.056) polymorphisms with IS risk. Haplotype analysis also did not yield significant findings for the HapA (rs17222814G-rs10507391T-rs4769874G-rs9551963A; OR=1.20; 95% CI: 0.91-1.56; P=0.192) and HapB (rs17216473A-rs10507391A-rs9315050A-rs17222842G; OR=1.11; 95% CI: 0.90-1.38; P=0.339) haplotypes.

CONCLUSION

Current evidence does not support an association of rs10507391, rs4769874, rs9551963, rs17222814, rs17222919, rs4073259, and HapA and HapB with IS risk.

Association between the polymorphism (rs17222919, -1316T/G) of 5-lipoxygenase-activating protein gene (ALOX5AP) and the risk of stroke: A meta analysis

BACKGROUND

The objective of this study was to evalutate the relationship between 5-lipoxygenase-activating protein gene (ALOX5AP) -rs17222919-1316T/G polymorphisms and the risk of stroke.

METHODS

Relative studies were searched in January 2018. Case-control studies with extractable data were selected. Four gene models were analyzed including, allele genetic model (G vs T), additive genetic model (GG vs TT, GT vs TT), recessive genetic model (GG vs GT + TT), and dominant genetic model (GG + GT vs TT). Effect sizes included odds ratio (OR) and 95% confidence interval (CI). Heterogeneity was assessed by using Q test and I test. Publication bias was evaluated by using Egger method. The reliability of the results was assessed with sensitivity analysis. All the data analysis was performed with R 3.10 software.

RESULTS

A total of 5 studies inclusing 8492 patients were included. There were significant relationship between ALOX5AP-rs17222919-1316T/G polymorphisms and stroke under all models (P < .05) except the additive genetic model GT versus TT (P > .05). No publication bias was noted. Sensitivity analysis indicated that the results were not stable.

CONCLUSION

This meta-analysis indicates that ALOX5AP-rs17222919-1316T/G may be a protective factor aginst stroke.

A tagging ALOX5AP polymorphism and risk of ischemic stroke in a northeastern Chinese Han population

OBJECTIVE

5-lipoxygenase-activating protein gene (ALOX5AP) has been recognized as a susceptibility gene for stroke. In this work, we explored the association of 6 ALOX5AP SNPs with cerebral infarction (CI) in a northeastern Chinese Han population, using a case-control design.

METHODS

A group of patients with cerebral infarction were randomly chosen as case group in northeastern Chinese Han population. Another comparative group of individuals without stroke were chosen as the control group. By utilizing TaqMan probe based real-time fluorescent PCR and DNA sequencing method, this study focused on 6 SNPs of ALOX5AP gene and analyzed the association with the hereditary susceptibility of cerebral infarction.

RESULTS

We found that, the rs9579646 G allele frequency was significantly associated with higher ischemic cerebral infarction. There was no significant difference of rs9551963, rs9315050, rs4769874, rs10507391 and rs4147064 genotype frequencies between the case and control group. Haplotype-based association analysis of the block involving rs9579646 and rs10507391 revealed that the increased risk of stroke was significantly associated with haplotype GT and GA.

CONCLUSION

These results suggested that the genetic variants in ALOX5AP might be related to the risk of stroke in northeastern Chinese Han population. The SNP rs9579646 may be a diagnostic index of cerebral infarction.

A promoter polymorphism (rs17222919, -1316T/G) of ALOX5AP gene is associated with decreased risk of ischemic stroke in two independent Chinese populations

No coding sequence variants of the gene encoding 5-lipoxygenase-activating protein (ALOX5AP) leading to amino acid substitutions have been identified. Therefore, variants in the ALOX5AP promoter region have received attention recently. The purpose of this study was to explore whether the promoter polymorphism rs17222919 is involved in the etiology of ischemic stroke (IS) in the Chinese Han population. We investigated the rs17222919 polymorphism by TaqMan genotyping in two independent Chinese Han samples: the first comprised 910 IS patients and 925 healthy inhabitants from the northern Henan Province, while the second included 1003 IS patients and 889 healthy controls from the southern Henan Province. Functional characterization of rs17222919 was performed by an in vitro luciferase assay. After adjusting for conventional risk factors, the G allele frequencies in the IS groups were significantly lower than that in the control groups of the two independent Chinese cohorts (19.0% vs. 22.9%, P = 0.004, odds ratio (OR) = 0.792, 95% confidence interval (CI) = 0.675-0.929; 18.8% vs. 22.9%, P = 0.002, OR = 0.782, 95% CI = 0.668-0.915, respectively). This was also observed in the large-artery atherosclerosis (LAA) and stroke of other undetermined etiology (SUE) subtypes (P = 0.019, OR = 0.815, 95% CI = 0.687-0.967; P = 0.021, OR = 0.815, 95% CI = 0.685-0.970, respectively). Additionally, the TG genotype and G allele frequencies were significantly lower in the IS compared with the control group in two female cohorts (P<0.05). Finally, the in vitro luciferase assay demonstrated that the G allele has a significantly lower transcription activity than the T allele (P = 0.031). Our study provides evidence that the promoter single nucleotide polymorphism (SNP) rs17222919 is a potential genetic protective factor for IS in the Chinese Han population.

Therapeutic effect of recombinant tissue plasminogen activator on acute cerebral infarction at different times

BACKGROUND

The study aimed to compare the therapeutic effect of recombinant tissue plasminogen activator (rt-PA) on the onset of acute cerebral infarction (ACI) at different time points of the first 6 hours.

METHODS

A retrospective analysis was conducted in 74 patients who received rt-PA thrombolysis treatment within 4.5 hours after ACI and another 15 patients who received rt-PA thrombolysis treatment between 4.5-6 hours after ACI.

RESULTS

National Institute of Health Stroke Scale (NIHSS) scores were statistically decreased in both groups (P>0.05) at 24 hours and 7 days after ACI. There was no significant difference in modified ranking scores and mortality at 90 days after the treatment between the two groups (P>0.05).

CONCLUSIONS

The therapeutic effect and mortality of rt-PA treatment in patients with ACI between 4.5-6 hours after the onset of the disease were similar to those in patients who received rt-PA within 4.5 hours after the onset of this disease. Therefore, intravenous thrombolytic therapy for ACI within 4.5-6 hours after ACI was effective and safe.

Association of ALOX5AP1 SG13S114T/A variant with ischemic stroke, stroke subtypes and aspirin resistance

The important role of genetic variants in the etiology and pathophysiology of stroke is being increasingly recognized. Simultaneously, the influence of genetic factors in the clinical outcome of drug therapy cannot be ignored. 5-lipoxygenase activating (ALOX5AP) gene involved in the synthesis of leukotrienes, has been recognized as an important gene contributing towards susceptibility of stroke risk. Leukotrienes are involved in the physiological mechanism of atherosclerotic events and inflammation. The present study was designed to identify the association of SG13S114T/A polymorphism in ALOX5AP1 gene with risk of stroke, its subtypes and aspirin resistance. We studied six hundred and ten patients with ischemic stroke and six hundred and ten age and sex matched healthy controls. The ischemic stroke was classified according to Trial of Org 10172 in Acute stroke Treatment. ALOX5AP1 SG13S114T/A polymorphism was determined using PCR RFLP methods. Follow-up was done for all the patients for a period of 3 months, 6 months and 12 months. The patients were classified into two groups responders and non-responders. The non-responders were identified to have a poor clinical outcome defined as a score of more than 2 on modified Rankin Scale Score and less than 5 on extended Glassgow Outcome Scale from stroke onset. We found statistically significant difference in the genotypic distribution between patients and controls (for AA vs TT, χ2=9.894; p=0.001, odds ratio=1.68 (95% confidence interval (CI); 1.215, 2.326). Significant difference was observed in the frequency of A and T alleles in patients and controls (A vs T χ(2)=10.23; p=0.001, odds ratio=1.301 (95% CI; 1.107, 1.528). Multiple logistic regression analysis revealed, the most predictive risk factor for stroke was AA genotype [adjusted odds ratio=1.660 (95% CI; 1.167-2.361) and p=0.005], hypertension, smoking and diabetes (p<0.001 in each case). We also found a significant association of AA genotype with intracranial large artery atherosclerosis (p=0.002, odds ratio=2.04, (95%CI; 1.279-3.275) and cardioembolism (p<0.001, odds ratio=4.73 (95% CI; 2.661-8.439). The risk of aspirin resistance was significantly higher among patients with AA genotype in comparison to carriers of homozygous TT genotype (AA vs TT, χ2=22.25, odds ratio=2.983, 95% CI; 1.884- 4.723, p<0.001). The frequency of recurrence and death events was more in non-responders. We didn't find a significant association of the aspirin dose with outcome. Our results indicate that the individuals bearing AA genotype of ALOX5AP1 SG13S114T/A polymorphism are more prone to stroke and bad outcome as well as with aspirin resistance than TA and TT genotypes.