Apolipoproteins B and A1 in Ischemic Stroke Subtypes

Differential distribution of plasma apoA-I and apoB levels and clinical significance of apoB/apoA-I ratio in ischemic stroke subtypes

Background and purpose

Ischemic stroke (IS) is classified into clinical subtypes and likely influenced by various lipid components. Nevertheless, the roles of apolipoprotein A-I (apoA-I), apolipoprotein B (apoB), and apoB/apoA-I ratio in different IS subtypes remain underexplored. This study aimed to investigate the differential distribution of plasma apoA-I and apoB levels among IS subtypes and to evaluate the predictive value of the apoB/apoA-I ratio in assessing IS subtypes and disease severity.

Methods

In this study, 406 IS patients were categorized into three IS-subtypes based on clinical manifestations and imaging assessment, including intracranial atherosclerosis-related IS patients (ICAS, n = 193), extracranial atherosclerosis-related IS patients (ECAS, n = 111), and small artery occlusion-related IS patients (SAO, n = 102). Plasma apoA-I and apoB levels were measured upon hospital admission. Random forest (RF) models were performed to assess predictive values of these apolipoproteins apoB, apoA-I and their ratio in assessing IS subtype stratification and disease severity.

Results

Serum apoA-I levels were significantly lower in ICAS compared to ECAS and SAO patients (p < 0.0001), while apoB levels were higher in ICAS patients (p < 0.0001). The apoB/apoA-I ratio was significantly higher in ICAS compared to ECAS and SAO patients (p < 0.0001). Correlation analyses found a significant correlation between the apoB/apoA-I ratio and conventional lipid components. Additionally, RF models and plots of variable importance and distribution of minimal depth revealed that the apoB/apoA-I ratio played the most influential predictor in predicting IS subtypes and stenosis severity.

Conclusion

Our study shows the differential distribution of apoA-I and apoB IS subtypes and reveals the significance of the apoB/apoA-I ratio in assessing IS subtypes and arterial stenosis severity. Further studies are warranted to validate these findings and enhance their clinical applicability.

Predictive value of ApoB/ApoA-I for recurrence within 1 year after first incident stroke

Background

ApoB/ApoA-I ratio is a reliable indicator of cholesterol balance, particularly in the prediction of ischemic events risk. The aim of this study was to investigate the prognostic value of ApoB/ApoA-I for stroke recurrence within 1 year after the first incident.

Methods

We retrospectively included patients who were first diagnosed with acute (<7 days after onset) ischemic stroke. Blood samples were collected on admission, and serum ApoB and ApoA-I concentrations were measured. We analyzed the relationship between ApoB/ApoA-I ratio and ischemic stroke recurrence within 1 year.

Results

A total of 722 patients with acute ischemic stroke were included, of whom 102 experienced stroke recurrence within 1 year, with a recurrence rate of 14.1%. Serum ApoB/ApoA-I concentrations on admission were higher in patients with stroke recurrence at 1 year compared with those with a good prognosis (P < 0.001). The Kaplan-Meier survival curve revealed a significant difference in cumulative stroke recurrence rates across ApoB/ApoA-I tertiles (log-rank P-value < 0.001). A positive correlation between the ApoB/ApoA-I ratio and the risk of stroke recurrence within 1 year was demonstrated using Cox regression analysis, which remained significant after adjusting for traditional risk factors [hazard ratio (HR) 4.007, 95% confidence interval (CI) 1.661-9.666]. This relationship was particularly strong in patients with LAA stroke (HR 4.955, 95% CI 1.591-15.434). Subgroup analysis further revealed that a high ApoB/ApoA-I ratio was strongly associated with stroke recurrence regardless of whether patients had high or low LDL-C levels.

Discussion

ApoB/ApoA-I ratio, measured during the acute phase of the first stroke, was positively correlated with the risk of stroke recurrence within 1 year.

The thrombus proteome in stroke reveals a key role of the innate immune system and new insights associated with its etiology, severity, and prognosis

BACKGROUND

Nowadays little is known about the molecular profile of the occluding thrombus of patients with ischemic stroke.

OBJECTIVES

To analyze the proteomic profile of thrombi in patients who experienced an ischemic stroke in order to gain insights into disease pathogenesis.

METHODS

Thrombi from an exploratory cohort of patients who experienced a stroke were obtained by thrombectomy and analyzed by sequential window acquisition of all theoretical spectra-mass spectrometry. Unsupervised k-means clustering analysis was performed to stratify patients who experienced a stroke. The proteomic profile was associated with both the neurological function (National Institute of Health Stroke Scale [NIHSS]) and the cerebral involvement (Alberta Stroke Program Early CT Score [ASPECTS]) prior to thrombectomy and the clinical status of patients at 3 months using the modified Rankin Scale. In an independent cohort of 210 patients who experienced a stroke, the potential role of neutrophils in stroke severity was interrogated.

RESULTS

Proteomic analysis identified 580 proteins in thrombi, which were stratified into 4 groups: hemostasis, proteasome and neurological diseases, structural proteins, and innate immune system and neutrophils. The thrombus proteome identified 3 clusters of patients with distinctive severity, prognosis, and etiology of the stroke. A protein signature clearly distinguished atherothrombotic and cardioembolic strokes. Several proteins were significantly correlated with the severity of the stroke (NIHSS and ASPECTS). Functional proteomic analysis highlighted the prominent role of neutrophils in stroke severity. This was in line with the association of neutrophil activation markers and count with NIHSS, ASPECTS, and the modified Rankin Scale score 90 days after the event.

CONCLUSION

The use of sequential window acquisition of all theoretical spectra-mass spectrometry in thrombi from patients who experienced an ischemic stroke has provided new insights into pathways and players involved in its etiology, severity, and prognosis. The prominent role of the innate immune system identified might pave the way for the development of new biomarkers and therapeutic approaches in this disease.

Elevated ApoB/ApoA-Ι ratio is associated with poor outcome in acute ischemic stroke

BACKGROUND

Apolipoproteins are known atherogenic factors that play important roles in many mechanisms related to acute ischemic stroke (AIS). However, it is unclear whether the ApoB/ApoA-Ι ratio is related to the prognosis of patients with AIS.

METHODS

We conducted a prospective cohort study in the Department of Neurology, Yangpu Hospital, School of Medicine, Tongji University and investigated the association between ApoB/ApoA-Ι ratio and poor outcomes at 3 months of AIS.

RESULTS

1,247 patients that met the eligibility criteria were enrolled in our study. We found that ApoA-Ι (Adjusted odds ratios (adjOR) 0.529, 95 %CI 0.327-0.855), ApoB (adjOR 3.015, 95 %CI 1.746-5.207), and ApoB/ApoA-Ι ratio (adjOR 3.986, 95 %CI 2.220-7.155) were independently associated with poor outcomes in acute ischemic stroke. During subgroup analysis, the ApoB/ApoA-Ι ratio was more likely associated with poor AIS outcomes in males and patients younger than 80 with SAO(Small Artery Occlusion) and no history of diabetes or statin use. Restricted cubic spline analyses explored the correlation between poor outcomes and ApoB/ApoA-Ι ratio.

CONCLUSIONS

Higher ApoB, lower ApoA-Ι, and higher ApoB/ApoA-Ι ratios were independently associated with poor outcomes in AIS. However, ApoB and ApoA-Ι were not related to hemorrhagic transformation in AIS.

Diagnostic Potential of Autophagy-5 Protein, Apolipoprotein B-48, and Oxidative Stress Markers in Serum of Patients with Early-Stage Ischemic Stroke

OBJECTIVE

Strokes are among the leading causes of death worldwide and have different characteristics. Different physiopathological mechanisms characterize the numerous subtypes of ischemic stroke (IS). In this study, we investigated the relationship between serum levels of autophagy-5 protein, apolipoprotein B-48, and oxidative stress markers in patients with ischemic stroke.

METHODS

For this study, 100 participants were recruited, of which 50 were patients with IS and 50 were healthy individuals. We conducted a case-control study at Imam Reza Hospital from March 2019 to April 2020. Serum levels of ATG5, apo B-48, and oxidative stress markers were determined in both groups. Our Receiver Operating Characteristic Analysis evaluated the additional diagnostic value of these factors in both groups.

RESULTS

Diabetes, smoking, age, sex, alcohol consumption, weight, and height did not differ significantly between the 2 groups (P > 0.05). However, the 2 groups had significant differences in hypertension and body mass index (P < 0.05). Fifty-four percent (27 patients) of patients with IS had an ischemic stroke in large vessels, while 46% (23 patients) had an ischemic stroke in small vessels. Serum levels of ATG5, apo B-48, and oxidative stress markers were higher in the case group than in the control group (P < 0.0001).

CONCLUSIONS

In patients with IS, serum levels of ATG5, apoB-48, malonaldehyde, total oxidative stress, and total antioxidant capacity can be used as novel biomarkers to predict or treat the disease.

A Genome-Wide Association Study of Genetic Variants of Apolipoprotein A1 Levels and Their Association with Vitamin D in Korean Cohorts

Dyslipidemia is an important independent risk factor for cardiovascular disease (CVD). Specifically, apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB), and the ApoB/A1 ratio have been linked to CVD. We conducted a genome-wide association study meta-analysis of two Korean cohorts containing a total of 12,924 patients to identify novel single nucleotide polymorphisms (SNPs) associated with ApoA1 and ApoB levels and the ApoB/A1 ratio. Additionally, an expression quantitative trait locus (eQTL) and differentially expressed genes (DEGs) analysis were performed. The statistically significant eQTL, DEG, and Gene Ontology (GO) results were used to explore the predicted interaction networks and retrieve the interacting genes and proteins. We identified three novel SNPs (rs11066280, p = 3.46 × 10−21; rs1227162, p = 2.98 × 10−15; rs73216931, p = 5.62 × 10−9) associated with ApoA1. SNP rs73216931 was an eQTL for KMT5A in the pancreas and whole blood. The network analysis revealed that HECTD4 and MYL2:LINC1405 are associated with AKT1. Our in silico analysis of ApoA1 genetic variants revealed heart muscle-related signals. ApoA1 also correlated positively with vitamin D, and genes associated with ApoA1 and vitamin D were found. Our data imply that more research into ApoA1 is needed to understand the links between dyslipidemia and CVD and vitamin D and CVD.

Predictive value of the apolipoprotein B/A1 ratio in intracerebral hemorrhage outcomes

Background and Aims

The apolipoprotein B (apoB)/apolipoprotein A1 (apoA1) ratio is a key indicator in predicting future cardiovascular outcomes. However, it is still unclear whether the ratio of apoB/apoA1 is a better predictor of the outcomes after intracerebral hemorrhage (ICH). Therefore, we aimed to assess the relationships between the ratio of apoB/apoA1 and functional outcomes, all‐cause mortality, and stroke recurrence in ICH patients.

Methods

Two hundred and sixteen Chinese ICH patients participated in this study from December 2018 to December 2019. Laboratory routine tests including hematology analysis, coagulation tests, and lipid levels were examined. The clinical outcomes included functional outcomes evaluated by the modified Rankin Scale score (mRS), all‐cause death, and stroke recurrence 1 year after discharge. Associations between the apoB/apoA1 ratio and the outcomes were evaluated using logistic regression analysis. Based on multivariate analysis, we constructed a nomogram. Univariate survival analysis was performed by the Kaplan–Meier method and log‐rank test. All the patients were classified into two groups by the median value of the apoB/apoA1 ratio: B1 < 0.8 and B2 ≥ 0.8.

Results

Of the 216 patients, 107 had an apoB/apoA1 ratio ≥ 0.8. Eighty‐five patients had poor functional outcomes (mRS ≥ 3), and 32 patients had severe functional outcomes (mRS ≥ 4). During the 1‐year follow‐up, a total of 18 patients died, and 13 patients had apoB/apoA1 ratio levels ≥0.8 during the 1‐year follow‐up period. Moreover, 16 recurrent strokes were recorded. Adjustments for age, sex, smoking, alcohol, body mass index, lipid levels, and hematoma site and volume showed that a high apoB/apoA1 ratio was significantly related to adverse functional outcomes and all‐cause mortality. The ORs for B2 versus B1 were 3.76 (95% CI: 1.37 to 10.40, p = 0.010), 22.74 (95% CI: 1.08 to 474.65, p = 0.044), and 7.23 (95% CI: 1.28 to 40.88, p = 0.025) for poor functional outcomes with mRS ≥ 3, mRS ≥ 4, and all‐cause mortality, respectively.

Conclusion

An increased apoB/apoA1 ratio at admission was independently related to poor functional outcome and all‐cause mortality in ICH patients at the 1‐year follow‐up.

Single-Nucleotide Polymorphisms in Oxidative Stress-Related Genes and the Risk of a Stroke in a Polish Population-A Preliminary Study

The present preliminary case-control study was undertaken to detect the potential association of six single nucleotide polymorphisms (SNPs) in oxidative stress-related genes: SOD2 (c.47T > C; rs4880), CAT (c.-89A > T; rs7943316), GPX4 (c.660T > A; rs713041), NOS1 (g.117803515C > T; rs1879417) and NOS2 (c.1823C > T; rs2297518 and c.-227G > C; rs10459953) and the occurrence of a stroke. The SNPs were determined using the TaqMan^® Allelic Discrimination Assay in 107 patients with strokes and 107 age- and sex-matched individuals who had not experienced cerebrovascular accidents. The T alleles of the rs4880 were positively correlated with a stroke (bootstrap OR 1.31; 1.07-1.59 95% CI). In the case of the rs713041, an association with the T allele was found (bootstrap OR 1.36; 1.12-1.67). In addition, the occurrence of a stroke was associated with the presence of the C allele of the rs1879417 (bootstrap OR 1.32; 1.09-1.61). We also found that the C/C genotype and C allele of the rs2297518 increased the risk of a stroke (bootstrap ORs 7.00; 4.34-11.29 and 4.96; 3.88-6.34, respectively). Moreover, the C allele of the rs10459953 was associated with an increased occurrence of this disease (bootstrap OR 1.31; 1.08-1.60). These results indicated that genetics variants in the SOD2, GPX4, NOS1 and NOS2 might be associated with susceptibility to strokes in the Polish population.

Similarities and Differences in Extracellular Vesicle Profiles between Ischaemic Stroke and Myocardial Infarction

Extracellular vesicles (EVs) are involved in intercellular signalling through the transfer of molecules during physiological and pathological conditions, such as ischaemic disease. EVs might therefore play a role in ischaemic stroke (IS) and myocardial infarction (MI). In the present study, we analysed the similarities and differences in the content of circulating EVs in patients with IS and MI. This prospective observational study enrolled 140 participants (81 patients with IS, 37 with MI and 22 healthy controls [HCs]). We analysed the protein and microRNA content from EVs using proteomics and reverse transcription quantitative real-time polymerase chain reaction and compared it between the groups. In the patients with IS and MI, we identified 14 common proteins. When comparing IS and MI, we found differences in the protein profiles (apolipoprotein B, alpha-2-macroglobulin, fibronectin). We also found lower levels of miR-340 and miR-424 and higher levels of miR-29b in the patients with IS and MI compared with the HCs. Lastly, we found higher miR-340 levels in IS than in MI. In conclusion, proteomic and miRNA analyses suggest a relationship between circulating EV content and the patient’s disease state. Although IS and MI affect different organs (brain and heart) with distinct histological characteristics, certain EV proteins and miRNAs appear to participate in both diseases, while others are present only in patients with IS.