Apolipoprotein E polymorphism and the risk of intracranial aneurysms in a Chinese population

P4HA2 knockdown prevents the progression of intracranial aneurysm by inducing prolyl hydroxylation of YAP1

Prolyl 4-hydroxylase subunit alpha 2 (P4HA2), a key enzyme modulating the post-transcription of proteins, was reported to be a causative gene in IA. Nevertheless, the exact function and mechanism of P4HA2 in the formation and rupture of IA is elusive. The current study first explored the expression of P4HA2 and its association with the clinicopathological demonstrations in patients with IA. In addition, an in vitro model of IA was established using H2O2 to stimulate vascular smooth muscle cells (VSMCs). The behaviors of treated VSMCs were evaluated using CCK-8, Wound healing, and Transwell assays. The expression of genes was detected by RT-qPCR and Western blot. Interaction between genes was confirmed using Luciferase Reporter assay and Co-immunoprecipitation (Co-IP) assay. Our results revealed that P4HA2 expression was upregulated in IA, especially ruptured IA; high P4HA2 expression correlates with unfavorable clinicopathological parameters. Through the in vitro experiments, it was discovered that P4HA2 knockdown rescued VSMCs from H2O2-induced viability impairment, enhancement in migration and apoptosis, switch from contractile phenotype, and augmentation of oxidative stress and inflammation. Mechanistically, P4HA2 was found to trigger the prolyl hydroxylation of YAP1 to negatively regulate the transcriptional activity of YAP1 in H2O2-challenged VSMCs. The effect of P4HA2 on H2O2-challenged VSMCs could be annulled by the mutation of YAP1 hydroxylation sites. In summary, P4HA2 served as a contributing factor during IA progression through its suppression on YAP1 activity by prolyl hydroxylation.

APOE gene polymorphism in ischemic stroke patients from Huizhou and its correlation with blood lipids and homocysteine

OBJECTIVES

To investigate the correlation between apolipoprotein E (APOE) gene polymorphisms and ischemic stroke and its relationship with blood lipids and homocysteine (HCY) level in Huizhou City.

MATERIALS AND METHODS

In this analytical cross-sectional study, we selected 2612 patients who underwent APOE genotyping from November 2019 to November 2021 at the Third People's Hospital of Huizhou. Among them, 2014 were ischemic stroke patients and 598 were non-stroke patients. The independent variables were ischemic stroke, different genotypes, and different alleles, while the dependent variables were blood lipid levels and HCY levels.

RESULTS

The distribution frequency of ε4 allele in stroke group was higher than that in non-stroke group (P < 0.05). Compared with ε4 allele carriers in the stroke group, the levels of lipid total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) in ε2 and ε3 allele carriers were significantly lower, while the levels of high-density lipoprotein cholesterol (HDL-C) were significantly higher (P < 0.01). The levels of lipid Lipoprotein a (LPa) and small dense low-density lipoprotein (sdLDL) in ε2 allele carriers in stroke group were significantly lower than those of ε4 allele carriers (P < 0.05). Logistics regression analysis showed that age, TC, HCY level and allele ε4 were positively correlated with the risk of ischemic stroke (P < 0.01), TG level was positively correlated with the risk of ischemic stroke in females (P < 0.01).

CONCLUSIONS

APOE gene polymorphism is associated with ischemic stroke, and ε4 allele carriers have a higher risk than ε3 allele carriers.

Intracranial Aneurysms and Lipid Metabolism Disorders: From Molecular Mechanisms to Clinical Implications

Many vascular diseases are linked to lipid metabolism disorders, which cause lipid accumulation and peroxidation in the vascular wall. These processes lead to degenerative changes in the vessel, such as phenotypic transformation of smooth muscle cells and dysfunction and apoptosis of endothelial cells. In intracranial aneurysms, the coexistence of lipid plaques is often observed, indicating localized lipid metabolism disorders. These disorders may impair the function of the vascular wall or result from it. We summarize the literature on the relationship between lipid metabolism disorders and intracranial aneurysms below.

Association of Apolipoprotein E Gene Polymorphism with Ischemic Stroke in Coronary Heart Disease Patients Treated with Medium-intensity Statins

OBJECTIVE

To study the association of apolipoprotein E(APOE) gene polymorphism with ischemic stroke (IS) in coronary heart disease (CHD) patients treated with medium-intensity statins.

METHODS

The retrospective study was performed on 662 samples including 169 CHD subjects complicated with IS, 296 subjects with CHD, and 197 control subjects. The APOE gene was obtained from case files. Univariable and multivariable logistic regression analyses were utilized to recognize the possible risks of CHD and IS.

RESULTS

The frequency of ε3-ε4 genotype was increased in the CHD group (p=0.013) and CHD-IS group (p=0.001), the frequency of ε4 allele was also increased in the CHD group (p=0.047) and the CHD-IS group (p=0.009) compared with control group. ε3-ε4 genotype was the independent risk for CHD and CHD-IS after adjusting for traditional risk factors with adjusted odds ratio (AOR) 2.210, 95%CI: 1.263-3.867, p=0.005) and (AOR 2.794, 95%CI: 1.539-5.072, p=0.002). The ε4 allele was also significantly associated with CHD (AOR 2.126, 95%CI: 1.265-3.575,=0.004) and CHD-IS (AOR 2.740, 95%CI: 1.569-4.784, p=0.001).

CONCLUSION

These results demonstrated that ε4 allele influenced the development of CHD with or without IS, especially for the genotype of ε3-ε4. CHD patients carrying the ε3-ε4 genotype and the ε4 allele were significantly associated with the incidence of IS, even if medium-intensity statins had been used.

Polymorphisms of Inflammatory Cytokine Genes and Risk for Intracranial Aneurysm: A Systematic Review and Meta-Analysis

PURPOSE

Inflammatory cytokines are thought to be involved in the pathogenesis of intracranial aneurysm (IA), although results among studies in the literature are inconsistent. This article sought to review studies on the associations among polymorphisms in inflammatory cytokine genes and IA risk and to provide recommendations for future research.

MATERIALS AND METHODS

A systematic search of PubMed, Embase, and Web of Science was conducted up to August 4, 2019. The associations between polymorphisms of inflammatory cytokine genes and IA risk were estimated by pooled odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses were performed according to race. Qualitative systematic review was conducted for variants that were studied in only one study. All analyses were performed using STATA 12.0.

RESULTS

13 studies investigating the associations between polymorphisms in five inflammatory cytokine genes (TNF-α, IL-1α, IL-1β, IL6, and IL-12B) and IA were reviewed. Combined results showed that the A allele of TNF-α rs1800629 polymorphism has a protective effect against IA (dominant model: OR=0.65, 95% CI=0.47-0.89, p=0.007). No associations were identified between polymorphisms in IL-1α rs1800587, IL-1β rs16944, IL6 rs1800795 and rs1800796, or IL-12B rs3212227 and IA risk.

CONCLUSION

This review demonstrated an association between TNF-α rs1800629 polymorphism and IA in Caucasians, illustrating the potentially important role of genes involved in inflammation in IA.

Association of Apolipoprotein E Polymorphisms with White Matter Lesions and Brain Atrophy

OBJECTIVE

Apolipoprotein E (ApoE) is mainly synthesized in the liver. So far, it is unknown the relationship among APOE gene polymorphisms and WML, brain atrophy. Therefore, the aim of the study was to assess the associations of APOE gene polymorphisms in patients with WML and brain atrophy.

METHODS

A total of 58 patients with WML, 128 patients with brain atrophy, 112 patients with co-occurrence of WML and brain atrophy and 95 healthy elderly volunteers were recruited from Renmin Hospital of WuHan University.

RESULTS

Allele E3 was the most common allele. The alleles E2 had significantly higher levels of ApoB and lower age in WML group. The alleles E2 was associated with the lower level of ApoB, LDL-Ch, TCh, and sdLDL in co-occurrence group. The E3/E3 genotype has higher level of sdLDL, but lower age and female frequency in WML. The E3/E4 genotype had higher level of TG, but lower age in WML. Gender, Age, E2, Hyperhomocysteinemia and UA were also significantly associated with disease progression.

CONCLUSION

This study found that clinical data, lipids and metabolic complications were closely related to ApoE genotypes and alleles, and also disease progression and type.

Prognostic significance of factor XIIIA promoter methylation status in aneurysmal subarachnoid haemorrhage (aSAH)

BACKGROUND

Aneurysmal subarachnoid hemorrhage is a life- threatening condition with high rate of disability and mortality. Apolipoprotein E (APOE) and Factor XIIIA (F13A) genes are involved in the pathogenetic mechanism of aneurysmal subarachnoid haemorrhage (aSAH). We evaluated the association of promoter methylation status of APOE and F13A gene and risk of aSAH.

METHODS

For evaluating the effect of hypermethylation in the promoter region of these genes with risk of aSAH, we conducted a case -control study with 50 aSAH patients and 50 healthy control. The methylation pattern was analysed using methylation specific PCR. The risk factors associated with poor outcome after aSAH was also analysed in this study. The outcome was assessed using Glasgow outcome score (GOS) after 3 months from the initial bleed.

RESULTS

The frequency of APOE and F13A methylation pattern showed insignificant association with risk of aSAH in this study. Gender stratification analysis suggests that F13A promoter methylation status was significantly associated with the risk of aSAH in male gender. Age, aneurysm located at the anterior communicating artery and diabetes mellitus showed significant association with poor outcome after aSAH.

CONCLUSION

There was no significant association with APOE promoter methylation with the risk as well as outcome of patients after aSAH. F13A promoter methylation status was significantly associated with risk of aSAH in male gender, with no significant association with outcome after aSAH.

Genetic susceptibility to cerebrovascular disease: A systematic review

Investigation of genetic susceptibility to cerebrovascular disease has been of growing interest. A systematic review of human studies assessing neurogenomic aspects of cerebrovascular disease was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. Any association study exploring genetic variants located in the exome associated with one of the major cerebrovascular diseases with at least 500 subjects was eligible for inclusion. Of 6874 manuscripts identified, 35 studies met the inclusion criteria. Most studies of interest focused on ischemic stroke and cerebrovascular occlusive disease. Large cohort genetic association studies on hemorrhagic cerebrovascular disease were less common. In addition to rare, well-established monogenic conditions with significant risk for cerebrovascular disease, a number of genetic variants are also relevant to cerebrovascular pathogenesis as part of a multifactorial process. The 45 polymorphisms identified were located in genes involved in processes related to endothelial and vascular health (15 (33.4%) variants), plasma lipid metabolism (10 (22.2%) variants), inflammation (9 (20%) variants), coagulation (3 (6.7%) variants), and blood pressure modulation (2 (4.4%) variants), and other (6 (13.3%) variants). This work represents a comprehensive overview of genetic variants in the exome relevant to ischemic and hemorrhagic stroke pathophysiology.

Polymorphism and plasma levels of apolipoprotein E and the risk of aneurysmal subarachnoid hemorrhage in a Chinese population: a case-control study

Background

Aneurysmal subarachnoid hemorrhage (aSAH) is the most common types of subarachnoid hemorrhage, which is a critical clinical problem with high morbidity, mortality, and economic impact. Recent studies have shown that APOE was a genetic risk factor of aSAH, however, the studies lack consistent conclusions and the evidence from Chinese Han population is rare.

Objective

To determine the relationship between APOE polymorphism and the incidence of aSAH in Chinese Fujian Han population and explore the possible mechanism of ApoE in the pathogenesis of aSAH.

Methods

A total of 131 patients newly diagnosed with aSAH were selected as aSAH group and 137 healthy subjects were selected as the control group. All the samples were analyzed for blood lipids and serum ApoE levels, and ApoE genotype was determined by a commercial chip and further confirmed with Sanger sequencing. An adjusted multivariate logistic regression analysis was carried out to estimate the effects of APOE polymorphism on the risk of aSAH.

Results

Compared with the controls, the serum TC, HDL-C and ApoA1 levels in aSAH were significantly lower: TC (4.52 ± 1.38 vs. 5.11 ± 0.86 mmol/L, P < 0.001), HDL-C (1.23 ± 0.46 vs. 1.44 ± 0.32 mmol/L, P < 0.001) and ApoA1 (1.20 ± 0.32 vs. 1.38 ± 0.25 g/L, P < 0.001). The distribution of ε2/ε3 genotype (19.08% vs. 9.49%, P = 0.038) and ε2 allele frequency (11.07% vs. 5.84%, P = 0.039) was significantly higher in aSAH than the healthy controls. The multivariate logistic regression identified that ApoE ε2 allele was independently associated with aSAH (OR = 2.083; and 95% CI = 1.045-4.153, P = 0.037). The serum ApoE in aSAH were significantly higher than controls (53.03 ± 24.64 vs. 45.06 ± 12.84 mg/L, P = 0.010).

Conclusion

APOE polymorphism might be associated with the incidence of aSAH in Chinese Fujian Han population. ApoE ε2 may be a risk factor for the incidence of aSAH, which may be related with the impacts of ApoE genotypes for the serum lipids, especially for the plasma levels of ApoE.

Association of APOE Gene Polymorphisms with Cerebral Infarction in the Chinese Population

Background

Apolipoprotein E (ApoE) is a multifunctional protein that plays an important role in lipoprotein metabolism. However, the relationship between APOE gene polymorphisms and cerebral infarction in the Chinese population remains unclear. Therefore, we studied the role of APOE gene polymorphisms in patients with cerebral infarction in a Chinese population.

Material/Methods

This study involved 906 patients with cerebral infarction and 1,141 individuals without cerebral infarction who served as controls. APOE genotypes were identified in all participants who participated in the study. Factors influencing cerebral infarction were also analyzed.

Results

Statistically significant variances in the distribution and frequencies of the APOE genotypes in the patients were observed (ɛ2/ɛ3 versus ɛ2/ɛ4 versus ɛ3/ɛ3=22.85% versus 7.62% versus 56.95%) and controls (ɛ2/ɛ3 versus ɛ2/ɛ4 versus ɛ3/ɛ3=17.27% versus 2.72% versus 66.87%; p<0.001). Univariate analysis showed that the APOE ɛ3/ɛ3 genotype [OR, 0.393 (95% CI, 0.237–0.653); p<0.001] and ɛ3/ɛ4 genotype [OR, 0.376 (95% CI 0.221–0.637); p<0.001] played a protective role against cerebral infarction in Chinese men.

Conclusions

Statistically significant variances in the distribution and frequencies of the APOE genotypes of the patients and controls were observed. The study demonstrated that the APOE ɛ3/ɛ3 and ɛ3/ɛ4 genotypes played a protective role against cerebral infarction in Chinese men, but not women. Additionally, the ɛ2/ɛ4 genotype may be a potential risk factor in men, whereas ɛ3/ɛ4 genotype may play a potential protective role against this disease in women.

Apolipoprotein E polymorphism and the risk of aneurysmal subarachnoid hemorrhage in a South Indian population

Background

The rupture of a brain aneurysm causes bleeding in the subarachnoid space. This is known as aneurysmal subarachnoid hemorrhage (aSAH). We evaluated the association of apolipoprotein E (APOE) polymorphism and the risk of aSAH in a South Indian population.

Methods

The study was performed on 200 subjects with aSAH and 253 healthy control subjects. Blood samples (5 ml) were used to isolate DNA and genotyping was performed for rs7412 and rs429358 using a Taqman allelic discrimination assay. Statistical software R.3.0.11 was used to statistically analyze the data and a p value < 0.05 was considered as statistically significant.

Results

We found a significant association with the risk of aSAH in ε3/ ε4 genetic model (OR = 1.91, 95% CI = 1.16-3.14, p = 0.01). However, in the other genetic models and allele frequency, there was no significant association with the risk of aSAH. In subtyping, we found a significant association of ε2 allele frequency with posterior communicating artery (PCOM) aneurysm (OR = 3.59, 95% CI = 1.11-11.64, p = 0.03).

Conclusion

Our results suggest that APOE polymorphism has an influence on the risk of aSAH in this South Indian population, specifically in the PCOM subtype.

Polymorphisms of apolipoprotein E and aneurysmal subarachnoid haemorrhage: A meta-analysis

Subarachnoid haemorrhage (SAH) is characterised by bleeding in the subarachnoid space in the brain. There are various polymorphisms in genes which are associated with this disease. We performed a systematic meta- analysis to investigate the relationship of APOE polymorphism on aSAH. A comprehensive literature search was done in the Pubmed database, Science Direct, Cochrane library and Google Scholar. The OR and 95% CI were evaluated for the gene and aSAH association using fixed and random effect models. Publication bias was assessed using Begg's funnel plot and Egger's regression test. All statistical evaluations were done using the software Review Manager 5.0 and Comprehensive Meta Analysis v2.2.023. A total of 9 studies were assessed on APOE polymorphism (1100 Cases, 2732 Control). Meta analysis results showed significant association in ε2/ ε2 versus ε3/ε3, ε2 versus ε3 genetic models and ε2 allele frequency. In subgroup analysis statistically significant association was observed in Asians in the genetic models ε2/ ε2 versus ε3/ε3, ε2/ε3 versus ε3/ε3, ε2 versus ε3 and also in ε2 allele frequency. However, in Caucasian population only ε2/ε2 versus ε3/ε3 genetic model showed significant association between APOE and risk of aSAH. In this meta-analysis study, the ε2/ε2 genotype is associated with increased risk of aSAH.