Plasma Proteomes and Genome-Wide Association Data for Causal Protein Identification in Stroke.

Plasma proteins are promising biomarkers and potential drug targets for stroke. This study aimed to explore whether there is a causal relationship between plasma proteins and subtypes of stroke using a Mendelian randomization (MR) approach. A two-sample bidirectional Mendelian randomization approach was employed to investigate the causal link between plasma proteins and stroke. Data on plasma proteins were obtained from three studies, including INTERVAL, and pooled stroke information was sourced from the MEGASTROKE consortium and the UK Biobank dataset, covering four subtypes of stroke. MR analyses were primarily conducted using inverse variance weighting, and sensitivity analyses were also performed. Finally, potential reverse causality was assessed using bidirectional MR. We identified two proteins causally associated with stroke: one as a potential therapeutic target and another as a protective factor. CXCL8 was found to be positively associated with the risk of developing large-artery atherosclerotic (LAA) stroke (OR, 1.005; 95% CI 1.001 to 1.010; p = 0.022), whereas TNFRSF11b was negatively correlated with the risk of developing LAA stroke (OR, 0.937; 95% CI 0.892 to 0.984; p = 0.010), independently of other stroke subtypes. Reverse bivariate analysis did not indicate that ischemic stroke was causally associated with CXCL8 and TNFRSF11b. There is a causal relationship between CXCL8 and TNFRSF11b with LAA stroke, independent of other subtypes. This study offers a new perspective on the genetics of stroke.

The role of triglyceride-glucose index in the differential diagnosis of atherosclerotic stroke and cardiogenic stroke.

OBJECTIVE: This study aims to investigate the role of the triglyceride glucose (TyG) index in differentiating cardiogenic stroke (CE) from large atherosclerotic stroke (LAA). METHOD: In this retrospective study, patients with acute ischemic stroke were recruited from the First Affiliated Hospital of Soochow University, Lianyungang Second People's Hospital and Lianyungang First People's Hospital. Their general data, medical history and laboratory indicators were collected and TyG index was calculated. Groups were classified by the TyG index quartile to compare the differences between groups. Logistic regression was utilized to assess the relationship between the TyG index and LAA. The receiver operating characteristic curve (ROC) curve was used to evaluate the diagnostic efficiency of the TyG index in differentiating LAA from CE. RESULT: The study recruited 1149 patients. After adjusting for several identified risk factors, groups TyG-Q2, TyG-Q3, and TyG-Q4 had a higher risk of developing LAA compared to group TyG-Q1(odds ratio (OR) = 1.63,95% confidence interval (CI) = 1.11-2.39, OR = 1.72,95%CI = 1.16-2.55, OR = 2.06,95%CI = 1.36-3.09). TyG has certain diagnostic value in distinguishing LAA from CE(AUC = 0.595, 95%CI0.566-0.623;P<0.001). CONCLUSION: Summarily, the TyG index has slight significance in the identification of LAA and CE; it is particularly a marker for their preliminary identification.

The association between constipation and stroke based on the NHANES and Mendelian randomization study.

Background: This study aimed to investigate putative causal effects between constipation and stroke using bidirectional Mendelian randomization (MR) analysis. Methods: Based on the cross-sectional study, logistic regression models were developed to assess the association between constipation and stroke prevalence. Subsequently, genome-wide association studies statistics were employed to perform MR analysis between constipation and stroke, as well as its subtypes. The inverse variance weighting (IVW) method was the primary method, complemented by four additional methods, namely weighted median, weighted mode, simple mode, and MR-Egger regression. Cochran's Q test, MR-Egger intercept test, MR Pleiotropy RESidual Sum and Outlier, and MR Steiger test were performed to assess heterogeneity and pleiotropy effects. Results: Constipation was associated with a greater risk of stroke even after adjusting for all covariates in logistic regression [odds ratio (OR) = 1.46, 95% confidence interval (CI) = 1.01-2.09, p = 0.042]. IVW MR analysis revealed that constipation affected large artery atherosclerosis (LAS; IVW OR = 1.5, 95% CI = 1.07-2.104, p = 0.019). No significant or suggestive association was observed with the risk of stroke or its various subtypes in MR analysis. Meanwhile, reverse MR analysis revealed no significant causal relationship between stroke or other stroke subtypes and constipation. The results of sensitivity analyses revealed no significant horizontal pleiotropy affecting causal estimates. Conclusion: While cross-sectional studies have established that constipation increases the risk of stroke, this two-sample bidirectional MR analysis revealed a positive correlation between constipation and LAS. However, no such correlation was observed between constipation and stroke, including its various subtypes.

Lipoprotein(a) and stroke: a two-sample Mendelian randomization study.

Background: To evaluate the causal relationship between lipoprotein(a) Lp(a) and stroke risk. Method: Adopting two grand scale genome-wide association study (GWAS) databases, the instrumental variables were selected on the basis that the genetic loci met the criteria of being independent of each other and closely related to Lp(a). Summary-level data for outcomes, ischemic stroke and its subtypes were acquired from the UK Biobank and MEGASTROKE consortium databases. Two-sample MR analyses were achieved using inverse variance-weighted (IVW) meta-analysis (primary analysis), weighted median analysis, and the MR Egger regression method. Multivariable-adjusted Cox regression models were also used for observational analysis. Result: Genetically predicted Lp(a) was marginally related with higher odds of total stroke (odds ratio (OR) [95% confidence intervals (CI)]: 1.003 [1.001-1.006], p = 0.010), ischemic stroke (OR [95% CI]: 1.004[1.001-1.007], p = 0.004), and large-artery atherosclerotic stroke (OR [95% CI]: 1.012 [1.004-1.019], p = 0.002) when the IVW estimator was used on the MEGASTROKE data. The associations of Lp(a) with stroke and ischemic stroke were also remarkable in the primary analysis using the UK Biobank data. Higher Lp(a) levels were also related with increased total stroke and ischemic stroke risk in the observational research data in the UK Biobank database. Conclusion: Genetically predicted higher Lp(a) perhaps rise the risk of total stroke, ischemic stroke, and large-artery atherosclerotic stroke.

Circular RNA hsa_circ_0003574 as a biomarker for prediction and diagnosis of ischemic stroke caused by intracranial atherosclerotic stenosis.

Background: Intracranial atherosclerotic stenosis (ICAS) is a common cause of first and recurrent ischemic stroke worldwide. Circular RNAs (circRNA)s have been recently suggested as candidate biomarkers in diagnosing and prognosis of ischemic stroke. A few circRNAs even serve as therapeutic targets that improves neurological function after ischemic stroke. However, the roles of circRNAs in ICAS caused ischemic stroke (ICAS-stroke) have not been fully understood. Therefore, in this study, we attempted to find some clues by investigating the different expression profiles of circRNAs between patients diagnosed with ICAS-stroke and normal control (NC)s. Methods: The OE Biotech Human ceRNA Microarray 4 × 180 K (47, 899 probes) screened circRNAs differentially expressed in peripheral blood in a discovery cohort (5 NCs versus five patients with ICAS-stroke). Afterwards, a validation cohort (31 NCs versus 48 patients with ICAS-stroke) was performed by quantitative polymerase chain reaction (qPCR). Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and CircRNA-microRNA-mRNA interaction network was performed to identify potential interactions with microRNAs and pathway-deregulated circRNAs. Results: There were 244 circRNAs differentially expressed in patients diagnosed with ICAS-stroke compared with NCs [fold change (FC) ≥ 2.0 and p-value<0.05]. Among the 244 circRNAs, 5 circRNAs (hsa_circ_0003574, hsa_circ_0010509, hsa_circ_0026628, hsa_circ_0074057, hsa_circ_0016993) were selected for following verification by qPCR. Only hsa_circRNA_0003574 was significantly upregulated in patients than in NCs. GO analysis indicated that predicted target genes involved various biological processes, cellular components, and molecular functions. KEGG analysis showed that many genes were enriched within the arginine and proline metabolism, pyrimidine metabolism, arginine and proline metabolism, lysosome, cytokine-cytokine receptor interaction, and RNA transport. The circRNA-miRNA-mRNA network analysis show the miRNAs that has_circ_0003574 likely interacts with. Conclusion: We observed that hsa_circRNA_0003574 is upregulated in patients with ICAS-stroke compared with NCs, indicating it may be a potential novel biomarker and therapeutic target for ICAS-stroke. In addition, we analyzed the laboratory results and found that homocysteine and glycosylated hemoglobin were elevated among ICAS-stroke patients. The relationship between hsa_circRNA_0003574 and these parameters requires further investigation.

Monocyte-to-lymphocyte ratio affects prognosis in LAA-type stroke patients.

Nowadays, the prognostic prediction of acute ischemic stroke (AIS) patients is still challenging because of the limited predictive properties of existing models. Blood-based biomarkers may provide additional information to the established prognostic factors. Markers of atherosclerosis have been identified as one of the most promising biomarkers for predicting prognosis, and inflammation, in turn, affects atherosclerosis. According to previous studies, the ratio of monocytes to lymphocytes (MLR) has been reported as a novel indicator of inflammation. Thus, our study was the first to conduct more in-depth research on the relationship between MLR and the prognosis of large artery atherosclerosis (LAA)-type AIS patients. A total of 296 patients with LAA-type stroke were recruited. Of these, 202 patients were assigned to the development cohort, and 94 patients were assigned to the validation cohort. In the development cohort, 202 patients were divided into groups A, B, C, and D according to the quartile method of MLR levels. The one-year prognosis of patients was tracked, and the modified Rankin scale (MRS, with a score ranging from 0 to 6) was mainly selected as the measurement result of the function. The relationship between MLR and prognosis was analyzed by building logistics regression models. The models showed that MLR made significant predictions in poor outcomes of LAA-type stroke patients (odds ratio: 4.037; p = 0.048). At the same time, receiver operating characteristics (ROC) curves were used to compare the predictive values between MLR and clinical prediction score (Barthel Index). This study demonstrated that patients with LAA-type stroke and high MLR had a poor prognosis. MLR might be a reliable, inexpensive, and novel predictor of LAA-type stroke prognosis.

TMAO as a Novel Predictor of Major Adverse Vascular Events and Recurrence in Patients with Large Artery Atherosclerotic Ischemic Stroke.

OBJECTIVES: To explore the association of plasma trimethylamine N-oxide (TMAO) concentration with large artery atherosclerotic (LAA) ischemic stroke and its role in predicting neurological outcome and major vascular event recurrence. MATERIALS AND METHODS: We performed a case-control study that included patients with first-ever LAA stroke as cases (n = 291) and asymptomatic patients as controls (n = 235). Clinical data and venous blood samples were collected within 72 hours after stroke. All subjects were followed for 3 months. TMAO level was detected by liquid chromatography mass spectrometry (LC-MS). Logistic and Cox proportional hazard regression were performed to evaluate plasma TMAO concentration as a predictor of LAA stroke and major vascular event recurrence, respectively. Kaplan-Meier survival analysis was performed to compare major vascular event recurrence between patients with high and low TMAO concentration. RESULTS: After adjusting for traditional stroke risk factors, the plasma TMAO level was significantly higher in the LAA stroke group than the control group (OR = 1.031, 95% CI 1.024-1.037, P < .001). At a cutoff level of 106.9 pg/ml, TMAO had a sensitivity of 63.23% and specificity of 80.00% in discriminating the LAA stroke subjects from the controls in Receiver operator characteristic (ROC) analysis. Kaplan-Meier survival analysis demonstrated TMAO plasma concentration was significantly relevant with recurrent vascular events (Log Rank, P = .006). Moreover, this association was still existed after adjusting for traditional risks (adjusted HR, 3.128; 95% CI, 1.018-9.610) in Cox regression model. But TMAO plasma levels were not relevant with functional disability after 3 months of the LAA stroke. CONCLUSION: Elevated plasma TMAO concentration was independently associated with LAA ischemic stroke. The risk of major vascular event recurrence increased by 2.128 times in the LAA stroke subjects with plasma TMAO level higher than 126.83 pg/mL. Plasma TMAO concentration might be a potential biomarker of major vascular event recurrence.

A Whole-Scope Evaluation of Cervicocephalic Atherosclerotic Burden is Essential to Predict 90-Day Functional Outcome in Large-Artery Atherosclerotic Stroke.

AIM: Cervicocephalic atherosclerosis (AS) of patients with large-artery atherosclerotic (LAA) stroke might be more closely correlated to the functional outcome than patients with stroke of other etiologies. We aimed to investigate whether a whole-scope evaluation of cervicocephalic AS condition was better at predicting the 90-day functional outcome of LAA stroke than evaluation of intracranial or cervical AS condition alone. METHODS: Patients with LAA stroke were consecutively enrolled in this study. Computed tomography angiography was performed to evaluate AS condition of various cervicocephalic arterial segments. AS conditions ranging from no AS plaque to complete arterial occlusion scored 0-4 points. Intracranial atherosclerotic burden (IAB) and cervical atherosclerotic burden (CAB) were in respective the sums of AS scores of all intracranial arterial segments and all cervical arterial segments. And the sum of them was intracranial and cervical atherosclerotic burden (ICAB). Relationships of these three scores with the 90-day unfavorable functional outcome (modified Rankin Scale[mRS] score ＞2 points) were compared. RESULTS: Of 172 patients who finished 90-day follow-up, only ICAB (adjusted odds ratio[OR]=1.10, 95% confidence interval[CI]:1.00-1.21, p=0.044) predicted 90-day unfavorable functional outcome independently of clinical factors, National Institutes of Health Stroke Scale (NIHSS) and mRS scores at admission. ICAB (adjusted hazard ratio[HR]=1.16, 95%CI:1.02-1.32, p=0.029) was related to 90-day recurrent ischemic stroke/death independently of clinical factors and was independently, positively correlated with NIHSS score at admission (r=0.16, p=0.047), whereas IAB and CAB were not. CONCLUSION: A whole-scope evaluation of cervicocephalic AS condition using ICAB outperformed evaluation of intracranial or cervical AS condition alone in predicting 90-day functional outcome of patients with LAA stroke.

Compositional and functional alterations of gut microbiota in patients with stroke.

BACKGROUND AND AIMS: There is accumulating evidence that gut microbiota plays a key role in cardiovascular diseases. Gut bacteria can transform dietary choline, l-carnitine, and trimethylamine N-oxide (TMAO) into trimethylamine, which can be oxidized into TMAO again in the liver. However, the alterations of the gut microbiota in large artery atherosclerotic (LAA) stroke and cardioembolic (CE) stroke have been less studied. METHODS AND RESULTS: We performed a case-control study in patients with LAA and CE types of strokes. We profiled the gut microbiome using Illumina sequencing of the 16S ribosomal RNA gene (V4-V5 regions), and TMAO was determined via liquid chromatography-tandem mass spectrometry. Our results showed that the TMAO levels in the plasma of patients with LAA and CE strokes were significantly higher than those in controls (LAA stroke, 2931 ± 456.4 ng/mL; CE stroke, 4220 ± 577.6 ng/mL; healthy control, 1663 ± 117.8 ng/mL; adjusted p < 0.05). The TMAO level in the plasma of patients with LAA stroke was positively correlated with the carotid plaque area (rho = 0.333, 95% CI = 0.08-0.55, p = 0.0093). Notably, the composition and the function of gut microbiota in the LAA stroke group were significantly different from those in the control group (FDR-adjusted p-value < 0.05). There was no significant association between gut microbiota and CE stroke in our study. CONCLUSION: This study provides evidence for significant compositional and functional alterations of the gut microbiome in patients with LAA stroke. Gut microbiota might serve as a potential biomarker for patients with LAA stroke.

Association between lncRNA genetic variants and susceptibility to large artery atherosclerotic stroke.

Studies have already illustrated the role of long non-coding RNAs (lncRNAs) in the progression of atherosclerosis, while the potential role of lncRNA gene variation in susceptibility to large artery atherosclerotic stroke (LAAS) remains controversial. We therefore conducted this study to explore and verify the gene expression modules of LAAS. Differentially expressed genes (DEGs) in atherosclerosis were screened in 3 patients with LAAS, and 3 healthy control patients. A further 31 individuals were used to screen DEGs, and MALAT1, MEG3, or SENCR were identified. Real-time PCR and western blotting were used to assess the difference in DEGs between the atherosclerotic and the non-atherosclerotic artery models. A total of 454 DEGs were detected from the initial screening step, and MALAT1, MEG3, or SENCR were applied to predict the risk of LAAS. The AUC of MALAT1, MEG3, and SENCR in predicting the risk of LAAS was 0.746 (95% CI: 0.398-0.753; P = 0.005), 0.575 (95% CI: 0.398-0.753; P = 0.389), and 0.629 (95% CI: 0.449- .808; P = 0.141), respectively. Moreover, there were significant differences between the atherosclerotic and non-atherosclerotic artery models for the expression of MALAT1, GCNT1, VEGFA, and VCAM-1. This study found that the MALAT1 contributes to LAAS susceptibility, and might play an important role in the progression of LAAS.

Comprehensive Analysis of Peripheral Exosomal circRNAs in Large Artery Atherosclerotic Stroke.

Exosomes are crucial vehicles in intercellular communication. Circular RNAs (circRNAs), novel endogenous noncoding RNAs, play diverse roles in ischemic stroke. Recently, the abundance and stability of circRNAs in exosomes have been identified. However, a comprehensive analysis of exosomal circRNAs in large artery atherosclerotic (LAA) stroke has not yet been reported. We performed RNA sequencing (RNA-Seq) to comprehensively identify differentially expressed (DE) exosomal circRNAs in five paired LAA and normal controls. Further, quantitative real-time PCR (qRT-PCR) was used to verify the RNA-Seq results in a cohort of stroke patients (32 versus 32). RNA-Seq identified a total of 462 circRNAs in peripheral exosomes; there were 25 DE circRNAs among them. Additionally, circRNA competing endogenous RNA (ceRNA) network and translatable analysis revealed the potential functions of the exosomal circRNAs in LAA progression. Two ceRNA pathways involving 5 circRNAs, 2 miRNAs, and 3 mRNAs were confirmed by qRT-PCR. In the validation cohort, receiver operating characteristic (ROC) curve analysis identified two circRNAs as possible novel biomarkers, and a logistic model combining two and four circRNAs increased the area under the curve compared with the individual circRNAs. Here, we show for the first time the comprehensive expression of exosomal circRNAs, which displayed the potential diagnostic and biological function in LAA stroke.

Novel Insights into the Potential Diagnostic Value of Circulating Exosomal IncRNA-Related Networks in Large Artery Atherosclerotic Stroke.

Exosomes show diagnostic and therapeutic promise as carriers of ncRNAs in diseases. LncRNAs in exosomes have been identified as being stable and avoided degradation by nucleolytic enzymes. Although lncRNAs have been confirmed to be important in cancers, no studies for exo-lncRNAs have been reported in LAA stroke. High-throughput sequencing was performed to detect the differential expression profiles of lncRNAs in five paired plasma-derived exosome samples from patients with LAA stroke and controls (matched on vascular risk factors). Exo-lncRNA-associated networks were predicted with a combination of multiple databases. The expression of the selected genes in the networks was confirmed by qRT-PCR in a validation set (LAA vs. controls = 30:30). Furthermore, ROC analysis was used to evaluate the diagnostic performance of the lncRNA-related networks. A total of 1,020 differentially expressed lncRNAs were identified in LAA stroke patients. GO and KEGG pathway analyses indicated that their target genes are involved in atherosclerosis-related pathways, including inflammation, cell adhesion, and cell migration. qRT-PCR confirmed that the expression trend of differential expressed genes was consistent with RNA-seq. Furthermore, the AUCs of the lnc_002015-related network and lnc_001350-related network were 0.959 and 0.97, respectively, in LAA stroke. Our study showed the differential expression of lncRNAs in plasma exosomes and presented related diagnostic networks for LAA stroke for the first time. The results suggested that exosomal lncRNA-related networks could be potential diagnostic tools in LAA stroke.

Circulating Exosomal circRNAs Contribute to Potential Diagnostic Value of Large Artery Atherosclerotic Stroke.

Large artery atherosclerotic (LAA) stroke is closely associated with atherosclerosis, characterized by the accumulation of immune cells. Early recognition of LAA stroke is crucial. Circulating exosomal circRNAs profiling represents a promising, noninvasive approach for the detection of LAA stroke. Exosomal circRNA sequencing was used to identify differentially expressed circRNAs between LAA stroke and normal controls. From a further validation stage, the results were validated using RT-qPCR. We then built logistic regression models of exosomal circRNAs based on a large replication stage, and receiver operating characteristic (ROC) curves were constructed to assess the diagnostic efficacy. Using exosomal circRNA sequencing, large sample validation, and diagnostic model construction revealed that exosomal circ_0043837 and circ_ 0001801were independent predictive factors for LAA stroke, and had better diagnostic efficacy than plasma circRNAs. In the atherosclerotic group (AS), we developed a nomogram for clinical use that integrated the two-circRNA-based risk factors to predict which patients might have the risk of plaque rupture. Circulating exosomal circRNAs profiling identifies novel predictive biomarkers for the LAA stroke and plaque rupture, with superior diagnostic value than plasma circRNAs. It might facilitate the prevention and better management of this disease.

SERPINA1 gene expression in whole blood links the rs6647 variant G allele to an increased risk of large artery atherosclerotic stroke.

The rs6647 variant G allele in SERPINA1 gene was reported to be associated with the risk of large artery atherosclerotic stroke (LAS), however, the mechanism remains unclear. Here, we performed a functional annotation of the rs6647 variant by using the software HaploReg version 4.1 (HaploReg v4.1). Next, the expression quantitative trait loci (eQTLs) analysis of multiple datasets was conducted for determining the association between the rs6647 and SERPINA1 expression in various tissues. Then, a case-control gene expression analysis was done using two independent ischemic stroke (IS) gene expression datasets. Finally, SERPINA1 expression in whole blood samples from 8 LAS patients and 14 healthy persons were compared. The functional annotation suggested that the rs6647 regulates gene expression in multiple human tissues especially in brain and blood. The eQTLs analysis revealed a significant association of the rs6647 G allele with increased expression of SERPINA1 gene only in whole blood. Compared with the controls, there was an increased expression of SERPINA1 gene in whole blood in both IS patients and LAS patients. SERPINA1 gene expression in whole blood bridges the rs6647 variant G allele with increased LAS risk, providing new insights into the mechanisms underlying role of the rs6647 in determining LAS risk.

Association between a functional interleukin 6 receptor genetic variant and the risk and functional outcome of large artery atherosclerotic stroke.

Purpose: To investigate whether the Asp358Ala of interleukin 6 receptor related to the risk and outcome of large artery atherosclerotic (LAA) stroke in Han Chinese.Materials and methods: A prospective cohort study was conducted on 768 patients with LAA stroke and 686 non-stroke controls. The genotypes of Asp358Ala polymorphism were determined using SNPscan technology. Associations between genotypes and the risk of LAA stroke were analyzed with logistic regression model.Results: CC genotype (P < 0.001) and AC genotype (P = 0.023) decreased the risk of LAA stroke compared with AA genotype. Multivariate logistic regression analysis revealed that CC genotype was significantly associated with the risk of LAA stroke (P = 0.002). In the subgroup analyses, polymorphisms of Asp358Ala were significantly associated with the risk of LAA stroke in additive model, dominant model and recessive model (P = 0.009, P = 0.017, P = 0.012, respectively) for male, but not for female. Further regression analysis showed that compared with participants with AA genotype and obesity, participants with CC genotype and non-obesity were less likely to suffer LAA stroke (P = 0.003). For male participants, these associations were still existed (additive model, P = 0.022). After 3-month follow-up, patients with C allele had good functional prognosis compared with patients with A allele (P = 0.009).Conclusion: The study demonstrated that the Asp358Ala polymorphism might be associated with susceptibility to the development and outcome of LAA stroke in Han Chines.

Association of Fibroblast Growth Factor 23 With Ischemic Stroke and Its Subtypes: A Mendelian Randomization Study.

Fibroblast growth factor 23 (FGF23), which is involved in the regulation of vitamin D, is an emerging independent risk factor for cardiovascular diseases. Previous studies have demonstrated a positive association between FGF23 and stroke. In this study, we aimed to assess the association of FGF23 with ischemic stroke and its subtypes by applying a Mendelian randomization (MR) framework. Five genetic variants obtained from a genome-wide association study involving 16,624 European subjects were used as valid instruments of circulating FGF23 levels. MR was applied to infer the causality of FGF23 levels and the risk of ischemic stroke using data from the MEGASTROKE consortium. Subsequently, several MR analyses, including inverse-variance weighted meta-analysis, MR-Egger, weighted median estimate (WME), MR Pleiotropy Residual Sum and Outlier were performed. The heterogeneity test analysis, including Cochran's Q, I 2 test and leave-one-out analysis were also applied. Furthermore, potential horizontal/vertical pleiotropy was assessed. Lastly, the power of MR analysis was tested. Three validated variants were found to be associated with circulating FGF23 levels and were used for further investigation. We found that high expression level of FGF23 was not associated with any ischemic stroke. However, a causal association between genetically predicted FGF23 levels and the risk of large-artery atherosclerotic stroke (LAS) was significant, with an odds ratio of 1.74 (95% confidence interval = 1.08-2.81) per standard deviation increase in circulating FGF23 levels. Our findings provide support for the causal association between FGF23 and LAS, and therefore, offer potential therapeutic targets for LAS. The specific roles of FGF23 in LAS and associated molecules require further investigation.

Associations between GUCY1A3 genetic polymorphisms and large artery atherosclerotic stroke risk in Chinese Han population: a case-control study.

BACKGROUND: Previous genome-wide association studies have found two single nucleotide polymorphisms (SNP) rs7692387 and rs1842896 located on or near the GUCY1A3 gene were associated with coronary artery disease (CAD). GUCY1A3 was considered to be involved in the process of atherosclerosis, but there was little information about the association between genotypic polymorphisms of the GUCY1A3 and large artery atherosclerotic (LAA) stroke. This study aimed to investigate the associations between the GUCY1A3 rs7692387, rs1842896 polymorphisms and LAA stroke susceptibility. METHODS: A total of 298 LAA stroke patients and 300 control subjects from a southern Chinese Han population were included. SNaPshot technique was used for genotype analysis. Associations between genotypes and LAA stroke susceptibility were analyzed with logistic regression model. RESULTS: Our study found that under the recessive model (TT vs. GT + GG), the GUCY1A3 rs1842896 polymorphism was significantly correlated with LAA stroke (OR = 1.48, 95%CI: 1.07-2.04, P = 0.018). After adjustment for its effects on age, gender, cigarette smoking, total cholesterol, low-density lipoprotein cholesterol, HbA1c, hypertension, diabetes mellitus, and CAD, the rs1842896 TT genotype retained association with increased susceptibility to LAA stroke (recessive model: adjusted OR = 1.96, 95%CI: 1.22-3.17, P = 0.006). However, association between rs7692387 polymorphism with LAA stroke was not observed. CONCLUSION: Our results indicate that the GUCY1A3 rs1842896 polymorphism is an LAA stroke risk factor in Southern Han Chinese.

The U-shaped Relationship Between Serum Methylene Tetrahydrofolate Reductase and Large-artery Atherosclerotic Stroke.

BACKGROUND: Methylene tetrahydrofolate reductase (MTHFR) gene polymorphisms have been reported to be associated with ischemic stroke. However, the association between serum MTHFR level and ischemic stroke has not yet been studied. We aimed to examine the association between them in patients with large-artery atherosclerotic stroke and community-based healthy controls. METHODS: This study includes three hundred ninety-five patients with large-artery atherosclerotic stroke from the China Antihypertensive Trial in Acute Ischemic Stroke (CATIS) and 395 age- and sex-matched healthy controls from Chinese communities. Serum MTHFR concentrations were examined and some conventional risk factors of stroke were collected. The association between serum MTHFR and large-artery atherosclerotic stroke was evaluated. RESULTS: A U-shaped association of serum MTHFR level with large-artery atherosclerotic stroke was observed (p for nonlinearity =0.008). After multivariate adjustment, the odds ratios (95% confidence intervals) of large-artery atherosclerotic stroke associated with the first, second, fourth, and fifth quintiles of MTHFR were 5.62 (1.10-28.87), 2.13 (0.51-8.99), 1.08 (0.21-5.56), and 2.31 (0.57-9.34), respectively, compared with the third quintiles of MTHFR. Adding MTHFR quintiles to a model containing conventional risk factors improved the predictive power for large-artery atherosclerotic stroke (continuous net reclassification improvement=63.78%, p<0.001; categorical net reclassification improvement=2.54%, p=0.012). CONCLUSION: There is a significant U-shaped relationship between serum MTHFR levels and largeartery atherosclerotic stroke. Our findings raise the possibility that serum MTHFR may have a potential role in the pathogenesis of large-artery atherosclerotic stroke.

Association of serum neuron-specific enolase and bilirubin levels with cerebral dysfunction and prognosis in large-artery atherosclerotic strokes.

PURPOSE: To explore the association of serum neuron-specific enolase (NSE) and bilirubin levels with cerebral dysfunction in the prognosis of large-artery atherosclerotic (LAA) stroke cases. METHODS: This study included 73 patients who suffered from LAA stroke and were divided into experimental group (n = 41) that had an increased serum NSE and bilirubin level, and control group (n = 32). At day 1, 7, and 14, the National Institutes of Health Stroke Scale (NIHSS) score, serum NSE, and bilirubin levels were measured. The modified Rankin Scale (mRS) was used to assess neurological functional recovery at 30 days. The good outcome rate was analyzed and tested using the Kaplan-Meier product-limit method and the log-rank test one year afterwards as a follow-up. RESULTS: The NIHSS scores, serum bilirubin, and NSE levels in the experimental group were significantly increased than that of control group at days 1, 7, and 14. There was a remarkable difference in the mRS scores and the good outcome rates between the two groups. Furthermore, the computed tomography detection rate of large-area cerebral infarctions was higher in the experimental group than that of control group. CONCLUSION: High serum NSE levels and hyperbilirubinemia might be biomarkers for a poor prognosis in the early identification of LAA strokes.