Genetics and Biomarkers of Moyamoya Disease: Significance of RNF213 as a Susceptibility Gene

Moyamoya syndrome after proton beam therapy in a pediatric patient with a pineal germ cell tumor and a germline polymorphism in RNF213

The effects of RNF213, which leads to moyamoya disease susceptibility, on radiation-induced moyamoya syndrome (MMS) remain unknown. We report a case of MMS after proton beam therapy (PBT) was deployed to treat a brain tumor in a patient with an RNF213 polymorphism. An 8-year-old boy underwent whole ventricular and local PBT for a pineal germ cell tumor and was diagnosed with radiation-induced MMS 9 months later. He underwent right and left revascularization surgeries for cerebral hemodynamic compromise at 17- and 18-years of age, respectively. Genetic analysis revealed a heterozygous germline polymorphism RNF213 p.R4810K. This is the first report to suggest an association between RNF213 polymorphism and radiation-induced MMS.

Mass cytometry revealed the circulating immune cell landscape across different Suzuki stages of Moyamoya disease

Moyamoya disease (MMD) is a cerebrovascular disorder marked by progressive arterial narrowing, categorized into six stages known as Suzuki stages based on angiographic features. Growing evidence indicates a pivotal role of systemic immune and inflammatory responses in the initiation and advancement of MMD. This study employs high-dimensional mass cytometry to reveal the immunophenotypic characteristics of peripheral blood immune cells (PBMCs) at various Suzuki stages, offering insights into the progression of MMD. PBMC samples from eight patients with early-stage MMD (Suzuki stages II and III) and eight patients with later-stage MMD (Suzuki stages IV, V, and VI) were analyzed using high-dimensional mass cytometry to evaluate the frequency and phenotype of immune cell subtypes. We identified 15 cell clusters and found that the immunological features of early-stage MMD and later-stage MMD are composed of cluster variations. In this study, we confirmed that, compared to later-stage MMD, the early-stage MMD group exhibits an increase in non-classical monocytes. As the Suzuki stage level increases, the proportions of plasmacytoid DCs and monocyte-derived DCs decrease. Furthermore, T cells, monocytes, DCs, and PMN-MDSCs in the early-stage MMD group show activation of the canonical NF-κB signaling pathway. We summarized and compared the similarities and differences between early-stage MMD patients and later-stage MMD patients. There is a potential role of circulating immune dysfunction and inflammatory responses in the onset and development of MMD.

Exploring the impact of pre-anastomosis cerebral microcirculation on cerebral hyperperfusion syndrome in superficial temporal artery-middle cerebral artery bypass surgery of moyamoya disease

Significance

Cerebral hyperperfusion syndrome (CHS), characterized by neurologic deficits due to postoperative high cerebral perfusion, is a serious complication of superficial temporal artery-middle cerebral artery (STA-MCA) surgery for moyamoya disease (MMD).

Aim

We aim to clarify the importance of assessing pre-anastomosis cerebral microcirculation levels by linking the onset of CHS to pre- and post-anastomosis hemodynamics.

Approach

Intraoperative laser speckle contrast imaging (LSCI) measured changes in regional cerebral blood flow (rCBF) and regional blood flow structuring (rBFS) within the cerebral cortical microcirculation of 48 adults with MMD.

Results

Following anastomosis, all MMD patients exhibited a significant increase in rCBF ( 279.60 % ± 120.00 % , p < 0.001 ). Changes in rCBF and rBFS showed a negative correlation with their respective baseline levels (rCBF, p < 0.001 ; rBFS, p = 0.005 ). Baseline rCBF differed significantly between CHS and non-CHS groups ( p = 0.0049 ). The areas under the receiver operating characteristic (ROC) curve for baseline rCBF was 0.753. Hemorrhagic MMD patients showed higher baseline rCBF than ischemic patients ( p = 0.036 ), with a marked correlation between pre- and post-anastomosis rCBF in hemorrhagic cases ( p = 0.003 ), whereas ischemic MMD patients did not.

Conclusion

Patients with low levels of pre-anastomosis baseline CBF induce a dramatic increase in post-anastomosis and show a high risk of postoperative CHS.

Moyamoya Vasculopathy and Moyamoya-Related Systemic Vasculopathy: A Review With Histopathological and Genetic Viewpoints

Systemic vasculopathy has occasionally been reported in cases of moyamoya disease (MMD). Since the pathological relationship between moyamoya vasculopathy (MMV) and moyamoya-related systemic vasculopathy (MMRSV) remains unclear, it was examined herein by a review of histopathologic studies in consideration of clinicopathological and genetic viewpoints. Although luminal stenosis was a common finding in MMV and MMRSV, histopathologic findings of vascular remodeling markedly differed. MMV showed intimal hyperplasia, marked medial atrophy, and redundant tortuosity of the internal elastic lamina, with outer diameter narrowing called negative remodeling. MMRSV showed hyperplasia, mainly in the intima and sometimes in the media, with disrupted stratification of the internal elastic lamina. Systemic vasculopathy has also been observed in patients with non-MMD carrying the RNF213 (ring finger protein 213) mutation, leading to the concept of RNF213 vasculopathy. RNF213 vasculopathy in patients with non-MMD was histopathologically similar to MMRSV. Cases of MMRSV have sometimes been diagnosed with fibromuscular dysplasia. Fibromuscular dysplasia is similar to MMD not only in the histopathologic findings of MMRSV but also from clinicopathological and genetic viewpoints. The significant histopathologic difference between MMV and MMRSV may be attributed to a difference in the original vascular wall structure and its resistance to pathological stress between the intracranial and systemic arteries. To understand the pathogeneses of MMD and MMRSV, a broader perspective that includes RNF213 vasculopathy and fibromuscular dysplasia as well as an examination of the 2- or multiple-hit theory consisting of genetic factors, vascular structural conditions, and vascular environmental factors, such as blood immune cells and hemodynamics, are needed.

RNF213 Polymorphisms in Intracranial Artery Dissection

The ring finger protein 213 gene (RNF213) is involved in several vascular diseases, both intracranial and systemic ones. Some variants are common in the Asian population and are reported as a risk factor for moyamoya disease, intracranial stenosis and intracranial aneurysms. Among intracranial vascular diseases, both moyamoya disease and intracranial artery dissection are more prevalent in the Asian population. We performed a systematic review of the literature, aiming to assess the rate of RNF213 variants in patients with spontaneous intracranial dissections. Four papers were identified, providing data on 53 patients with intracranial artery dissection. The rate of RNF213 variants is 10/53 (18.9%) and it increases to 10/29 (34.5%), excluding patients with vertebral artery dissection. All patients had the RNF213 p.Arg4810Lys variant. RNF213 variants seems to be involved in intracranial dissections in Asian cohorts. The small number of patients, the inclusion of only patients of Asian descent and the small but non-negligible coexistence with moyamoya disease familiarity might be limiting factors, requiring further studies to confirm these preliminary findings and the embryological interpretation.

Knockdown the moyamoya disease susceptibility gene, RNF213, upregulates the expression of basic fibroblast growth factor and matrix metalloproteinase-9 in bone marrow derived mesenchymal stem cells

Moyamoya disease (MMD) is a chronic, progressive cerebrovascular occlusive disease. Ring finger protein 213 (RNF213) is a susceptibility gene of MMD. Previous studies have shown that the expression levels of angiogenic factors increase in MMD patients, but the relationship between the susceptibility gene RNF213 and these angiogenic mediators is still unclear. The aim of the present study was to investigate the pathogenesis of MMD by examining the effect of RNF213 gene knockdown on the expression of matrix metalloproteinase-9 (MMP-9) and basic fibroblast growth factor (bFGF) in rat bone marrow-derived mesenchymal stem cells (rBMSCs). Firstly, 40 patients with MMD and 40 age-matched normal individuals (as the control group) were enrolled in the present study to detect the levels of MMP-9 and bFGF in serum by ELISA. Secondly, Sprague-Dawley male rat BMSCs were isolated and cultured using the whole bone marrow adhesion method, and subsequent phenotypic analysis was performed by flow cytometry. Alizarin red and oil red O staining methods were used to identify osteogenic and adipogenic differentiation, respectively. Finally, third generation rBMSCs were transfected with lentivirus recombinant plasmid to knockout expression of the RNF213 gene. After successful transfection was confirmed by reverse transcription-quantitative PCR and fluorescence imaging, the expression levels of bFGF and MMP-9 mRNA in rBMSCs and the levels of bFGF and MMP-9 protein in the supernatant of the culture medium were detected on the 7th and 14th days after transfection. There was no significant difference in the relative expression level of bFGF among the three groups on the 7th day. For the relative expression level of MMP-9, there were significant differences on the 7th day and 14th day. In addition, there was no statistically significant difference in the expression of bFGF in the supernatant of the RNF213 shRNA group culture medium, while there was a significant difference in the expression level of MMP-9. The knockdown of the RNF213 gene affects the expression of bFGF and MMP-9. However, further studies are needed to determine how they participate in the pathogenesis of MMD. The findings of the present study provide a theoretical basis for clarifying the pathogenesis and clinical treatment of MMD.

Assessing donor-recipient arterial pressure dynamics in STA-MCA bypass for moyamoya disease

BACKGROUND

In bypass surgery for moyamoya disease (MMD), the superficial temporal artery's (STA) pressure needs to surpass that of the cortical M4 recipient of the middle cerebral artery (MCA), boosting cerebral blood flow into the MCA and enhancing cerebral circulation. This study investigates the STA-MCA arterial pressure parameters and gradients during bypass surgery, aiming to deepen our understanding of hemodynamic shifts pre- and post-operation.

METHODS

DSA imaging data were prospectively collected from patients diagnosed with bilateral MMD who underwent STA-MCA bypass surgery between 2022 and 2023 and stratified according to the Suzuki stage. The mean arterial pressure (MAP) of the donor and recipient arteries was directly measured during the STA-MCA bypass procedure, and these data were statistically analyzed and evaluated.

RESULTS

Among 48 MMD patients, Suzuki grading revealed that 43.8% were in early stages (II and III), while 56.2% were in advanced stages (IV, V, and VI). Predominantly, 77.1% presented with ischemic-type MMD and 22.9% with hemorrhagic type. Pre-bypass assessments showed that 62.5% exhibited antegrade blood flow direction, and 37.5% had retrograde. The mean recipient artery pressure was 35.0 ± 2.3 mmHg, with a mean donor-recipient pressure gradient (δP) of 46.4 ± 2.5 mmHg between donor and recipient arteries. Post-bypass, mean recipient artery pressure increased to 73.3 ± 1.6 mmHg. No significant correlation (r = 0.18, P = 0.21) was noted between δP and Suzuki staging.

CONCLUSION

Our study elucidated that cerebral blood pressure significantly decreases beyond the moyamoya network at the distal M4 segment. Furthermore, we observed bidirectional flow in MCA territories and a significant positive pressure gradient between the STA and M4 segments. The lack of correlation between Suzuki stages and M4 pressures indicates that angiographic severity may not reflect hemodynamic conditions before surgery, highlighting the need for customized surgical approaches.

Circulating immune cell landscape and T-cell abnormalities in patients with moyamoya disease

BACKGROUND

Moyamoya disease (MMD) stands as a prominent cause of stroke among children and adolescents in East Asian populations. Although a growing body of evidence suggests that dysregulated inflammation and autoimmune responses might contribute to the development of MMD, a comprehensive and detailed understanding of the alterations in circulating immune cells associated with MMD remains elusive.

METHODS

In this study, we employed a combination of single-cell RNA sequencing (scRNA-seq), mass cytometry and RNA-sequencing techniques to compare immune cell profiles in peripheral blood samples obtained from patients with MMD and age-matched healthy controls.

RESULTS

Our investigation unveiled immune dysfunction in MMD patients, primarily characterized by perturbations in T-cell (TC) subpopulations, including a reduction in effector TCs and an increase in regulatory TCs (Tregs). Additionally, we observed diminished natural killer cells and dendritic cells alongside heightened B cells and monocytes in MMD patients. Notably, within the MMD group, there was an augmented proportion of fragile Tregs, whereas the stable Treg fraction decreased. MMD was also linked to heightened immune activation, as evidenced by elevated expression levels of HLA-DR and p-STAT3.

CONCLUSIONS

Our findings offer a comprehensive view of the circulating immune cell landscape in MMD patients. Immune dysregulation in patients with MMD was characterized by alterations in T-cell populations, including a decrease in effector T-cells and an increase in regulatory T-cells (Tregs), suggest a potential role for disrupted circulating immunity in the aetiology of MMD.

Rapidly Progressive Contralateral Internal Carotid Artery Stenosis After COVID-19 Infection in a Down Syndrome Patient With Unilateral Moyamoya Arteriopathy

Moyamoya arteriopathy is a condition where chronic, progressive stenosis of large intracranial arteries, primarily of the anterior circulation, results in ischemia and the growth of small, abnormal collateral vessels. There is increasing evidence that infectious pathologies, such as COVID-19, may serve as a sort of trigger, or "second hit," for the development of moyamoya arteriopathy. In this article, we present the case of a 13-year-old female with Down syndrome and unilateral moyamoya arteriopathy who developed contralateral internal carotid artery (ICA) dissection and thrombus in the setting of a positive COVID-19 test and subsequently developed rapidly progressive contralateral ICA and bilateral anterior cerebral artery (ACA) moyamoya-like stenosis. The rapidly progressive contralateral ICA and bilateral ACA moyamoya-like stenosis are likely multifactorial in nature. The contralateral ICA may have had a predisposition for injury and stenosis due to the preexisting moyamoya arteriopathy, making stenosis more likely after COVID-19-induced vascular inflammation and injury as well as after a possible thrombectomy-associated injury. Based on this presentation, patients with moyamoya arteriopathy may be at risk for rapid progression of their moyamoya pathology when exposed to catalysts, including infection, such as COVID-19, and vascular injury, such as thrombectomy-induced injury. In these circumstances, high suspicion and close monitoring are essential for addressing ischemia related to the stenosis before permanent injury.

Molecular Biomarkers Affecting Moyamoya Disease

Although the pathogenetic pathway of moyamoya disease (MMD) remains unknown, studies have indicated that variations in the RING finger protein RNF 213 is the strongest susceptible gene of MMD. In addition to the polymorphism of this gene, many circulating angiogenetic factors such as growth factors, vascular progenitor cells, inflammatory and immune mediators, angiogenesis related cytokines, as well as circulating proteins promoting intimal hyperplasia, excessive collateral formation, smooth muscle migration and atypical migration may also play critical roles in producing this disease. Identification of these circulating molecules biomarkers may be used for the early detection of this disease. In this chapter, how the hypothesized pathophysiology of these factors affect MMD and the interactive modulation between them are summarized.

Recurrent Cerebral Infarction Due to Moyamoya Disease Complicated With Systemic Lupus Erythematosus: A Case Report and Literature Review

INTRODUCTION

We report a rare case of moyamoya disease caused by an RNF213 mutation, complicated with systemic lupus erythematosus.

CASE REPORT

A 32-year-old woman experienced 4 cerebral ischemia stroke events within 6 months. The main symptom was left limb weakness with blurred vision in the right eye. Results of digital subtraction angiography conducted at another hospital were consistent with moyamoya disease. On genetic testing, we found that the patient carried 2 mutations in the moyamoya disease-related gene RNF213 (p.R4810K, p.T1727M). On the basis of the laboratory immunologic indicators, such as positive antibodies and abnormal immunoglobulin levels and imaging examinations, the patient was finally diagnosed as moyamoya disease complicated with systemic lupus erythematosus. She was treated with aspirin, butylphthalide, urinary kallidinogenase, and sodium methylprednisolone.

CONCLUSIONS

This was a 32-year-old young patient diagnosed with moyamoya disease carrying RNF213 gene mutation and accompanied by lupus with cerebral ischemic event as the first occurrence. The patient's condition was complex; therefore, comprehensive analysis and in-depth consideration were needed to avoid a missed diagnosis and misdiagnosis. When the primary disease cannot be identified, genetic testing can help to clarify the diagnosis of moyamoya disease.

RNF213 loss-of-function promotes pathological angiogenesis in moyamoya disease via the Hippo pathway

Moyamoya disease is an uncommon cerebrovascular disorder characterized by steno-occlusive changes in the circle of Willis and abnormal vascular network development. Ring finger protein 213 (RNF213) has been identified as an important susceptibility gene for Asian patients, but researchers have not completely elucidated whether RNF213 mutations affect the pathogenesis of moyamoya disease. Using donor superficial temporal artery samples, whole-genome sequencing was performed to identify RNF213 mutation types in patients with moyamoya disease, and histopathology was performed to compare morphological differences between patients with moyamoya disease and intracranial aneurysm. The vascular phenotype of RNF213-deficient mice and zebrafish was explored in vivo, and RNF213 knockdown in human brain microvascular endothelial cells was employed to analyse cell proliferation, migration and tube formation abilities in vitro. After bioinformatics analysis of both cell and bulk RNA-seq data, potential signalling pathways were measured in RNF213-knockdown or RNF213-knockout endothelial cells. We found that patients with moyamoya disease carried pathogenic mutations of RNF213 that were positively associated with moyamoya disease histopathology. RNF213 deletion exacerbated pathological angiogenesis in the cortex and retina. Reduced RNF213 expression led to increased endothelial cell proliferation, migration and tube formation. Endothelial knockdown of RNF213 activated the Hippo pathway effector Yes-associated protein (YAP)/tafazzin (TAZ) and promoted the overexpression of the downstream effector VEGFR2. Additionally, inhibition of YAP/TAZ resulted in altered cellular VEGFR2 distribution due to defects in trafficking from the Golgi apparatus to the plasma membrane and reversed RNF213 knockdown-induced angiogenesis. All these key molecules were validated in ECs isolated from RNF213-deficient animals. Our findings may suggest that loss-of-function of RNF213 mediates the pathogenesis of moyamoya disease via the Hippo pathway.

Gut microbiota in adults with moyamoya disease: characteristics and biomarker identification

Background and purpose

When it comes to the onset of moyamoya disease (MMD), environmental variables are crucial. Furthermore, there is confusion about the relationship between the gut microbiome, an environmental variable, and MMD. Consequently, to identify the particular bacteria that cause MMD, we examined the gut microbiome of MMD individuals and healthy controls (HC).

Methods

A prospective case-control investigation was performed from June 2021 to May 2022. The fecal samples of patients with MMD and HC were obtained. Typically, 16S rRNA sequencing was employed to examine their gut microbiota. The QIIME and R softwares were used to examine the data. The linear discriminant analysis effect size analysis was used to determine biomarkers. Multivariate analysis by linear models (MaAsLin)2 were used to find associations between microbiome data and clinical variables. Model performance was assessed using the receiver operating characteristic curve and the decision curve analysis.

Results

This investigation involved a total of 60 MMD patients and 60 HC. The MMD group's Shannon and Chao 1 indices were substantially lower than those of the HC cohort. β-diversity was significantly different in the weighted UniFrac distances. At the phylum level, the relative abundance of Fusobacteriota/Actinobacteria was significantly higher/lower in the MMD group than that in the HC group. By MaAsLin2 analysis, the relative abundance of the 2 genera, Lachnoclostridium and Fusobacterium, increased in the MMD group, while the relative abundance of the 2 genera, Bifidobacterium and Enterobacter decreased in the MMD group. A predictive model was constructed by using these 4 genera. The area under the receiver operating characteristic curve was 0.921. The decision curve analysis indicated that the model had usefulness in clinical practice.

Conclusions

The gut microbiota was altered in individuals with MMD, and was characterized by increased abundance of Lachnoclostridium and Fusobacterium and decreased abundance of Bifidobacterium and Enterobacter. These 4 genera could be used as biomarkers and predictors in clinical practice.

Technical evolution of pediatric neurosurgery: moyamoya disease

Moyamoya disease (MMD) is a rare steno-occlusive disease of the bilateral internal carotid arteries that predominantly occurs in East Asia. Since the first description of the MMD by Suzuki and Takaku in 1969, significant advances have been made in both basic and clinical understanding of the disease. The incidence and prevalence of pediatric MMD have increased, potentially due to improved detection rates. The advancement of neuroimaging techniques has enabled MRI-based diagnostics and detailed visualization of the vessel wall. Various methods of surgical treatments are successful in pediatric MMD patients, and recent studies emphasize the importance of reducing postoperative complications since the goal of MMD surgery is to prevent future cerebral infarction and hemorrhage. Long-term outcomes following appropriate surgical treatment in pediatric MMD patients have shown promising results, including favorable outcomes in very young patients. Further studies with a large patient cohort are needed to establish individualized risk group stratification for determining the optimal timing of surgical treatment and to conduct multidisciplinary outcome assessments.

Difference in Clinical Phenotype, Mutation Position, and Structural Change of RNF213 Rare Variants Between Pediatric and Adult Japanese Patients with Moyamoya Disease

It is unclear how rare RNF213 variants, other than the p.R4810K founder variant, affect the clinical phenotype or the function of RNF213 in moyamoya disease (MMD). This study included 151 Japanese patients with MMD. After performing targeted resequencing for all coding exons in RNF213, we investigated the clinical phenotype and statistically analyzed the genotype-phenotype correlation. We mapped RNF213 variants on a three-dimensional (3D) model of human RNF213 and analyzed the structural changes due to variants. The RNF213 p.R4810K homozygous variant, p.R4810K heterozygous variant, and wild type were detected in 10 (6.6%), 111 (73.5%), and 30 (19.9%) MMD patients, respectively. In addition, 15 rare variants were detected in 16 (10.6%) patients. In addition to the influence of the p.R4810K homozygous variant, the frequency of cerebral infarction at disease onset was higher in pediatric patients with other rare variants (3/6, 50.0%, P = 0.006) than in those with only the p.R4810K heterozygous variant or with no variants (2/51, 3.9%). Furthermore, on 3D modelling of RNF213, the majority of rare variants found in pediatric patients were located in the E3 module and associated with salt bridge loss, contrary to the results for adult patients. The clinical phenotype of rare RNF213 variants, mapped mutation position, and their predicted structural change differed between pediatric and adult patients with MMD. Rare RNF213 variants, in addition to the founder p.R4810K homozygous variant, can influence MMD clinical phenotypes or structural change which may contribute to the destabilization of RNF213.

Clinical characteristics and intracranial arterial lesions of non-young adult ischemic stroke patients with RNF213 p.R4810K variant

BACKGROUND

Although RNF213 p.R4810K, a genetic susceptibility variant for moyamoya disease (MMD), is associated with intracranial artery stenosis/occlusion (ICASO), the impact of this variant on ischemic stroke patients in non-young adults is unclear. We aimed to determine the characteristics of non-young adult stroke patients with RNF213 p.R4810K.

METHODS

We retrospectively identified acute ischemic stroke patients ≥50 years who were admitted to our hospital and underwent intracranial vascular imaging. We reviewed the patients with RNF213 p.R4810K and compared stroke characteristics and the frequency and location of ICASO between patients with and without the variant.

RESULTS

Among 341 patients, RNF213 p.R4810K was identified in 7 patients (2.1%). Five of the 7 patients with the variant (71%) had multiple ICASO without any finding of MMD and remaining 2 patients had no ICASO. The presumed etiologies of ICASO were atherosclerosis in 3 cases, vasculitis in 1, and undetermined vasculopathy in 1. ICASO in the anterior circulation was more common in patients with the variant than in those without (71% vs. 25%). The internal carotid artery, the M1 segment of the middle cerebral artery, the A1 segment of the anterior cerebral artery, and the P1 segment of the posterior cerebral artery, which were the most frequently affected arteries in MMD, were more often affected in the variant group.

CONCLUSIONS

Non-young adult stroke patients with RNF213 p.R4810K are more likely to have ICASO in arterial segments commonly affected in MMD. The etiology of their ICASO exhibited diverse mechanisms, possibly depending on vascular risk and other environmental factors.

Factors Influencing Collateral Circulation Formation After Indirect Revascularization for Moyamoya Disease: a Narrative Review

Indirect revascularization is one of the main techniques for the treatment of Moyamoya disease. The formation of good collateral circulation is a key measure to improve cerebral blood perfusion and reduce the risk of secondary stroke, and is the main method for evaluating the effect of indirect revascularization. Therefore, how to predict and promote the formation of collateral circulation before and after surgery is important for improving the success rate of indirect revascularization in Moyamoya disease. Previous studies have shown that vascular endothelial growth factor, endothelial progenitor cells, Caveolin-1, and other factors observed in patients with Moyamoya disease may play a key role in the generation of collateral vessels after indirect revascularization through endothelial hyperplasia and smooth muscle migration. In addition, mutations in the genetic factor RNF213 have also been associated with this process. This study summarizes the factors and mechanisms influencing collateral circulation formation after indirect revascularization in Moyamoya disease.

Association between statin therapy and the risk of stroke in patients with moyamoya disease: a nationwide cohort study

BACKGROUND AND OBJECTIVE

Knowledge regarding the pharmacological treatment for moyamoya disease (MMD), a chronic and progressive cerebrovascular disease conferring greater stroke risk, is limited. In the present study, whether statin therapy is associated with a reduced risk of stroke in patients with MMD was investigated.

METHODS

This was a retrospective cohort study in which the occurrence of stroke in patients with newly diagnosed MMD was investigated using the nationwide health insurance database in Korea from January 2007 to March 2021. A multivariable Cox proportional hazards regression model was constructed for stroke, in which statin therapy after MMD diagnosis was treated as a time-dependent variable. Adjustment was done for sex, age, presence of comorbidities, concurrent stroke, revascularisation surgery and treatment with antiplatelets.

RESULTS

The present study included 13 373 newly diagnosed patients with MMD; 40.8% had a concurrent stroke at the time of MMD diagnosis. During the mean follow-up of 5.1±3.3 years, 631 patients (4.7%) suffered a stroke event (haemorrhagic stroke: 458 patients, ischaemic stroke: 173 patients). Statin therapy after MMD diagnosis was significantly associated with a reduced risk of stroke (adjusted HR 0.74; 95% CI 0.60 to 0.91, p=0.004). In the secondary outcome analysis, the risk of haemorrhagic stroke (adjusted HR 0.74; 95% CI 0.58 to 0.95, p=0.018) and ischaemic stroke (adjusted HR 0.75; 95% CI 0.52 to 1.08, p=0.124) were reduced with the statin treatment. Taking statins was also associated with a lower risk of all-cause mortality (adjusted HR 0.47; 95% CI 0.33 to 0.67, p<0.001).

CONCLUSION

In patients with MMD, statin therapy was associated with a reduced risk of subsequent stroke. The findings indicate statin treatment may be beneficial for patients with MMD, however the results should be confirmed in randomised controlled trials.

Plasma urea cycle metabolite levels and the risk of moyamoya disease

Background and purpose

Urea cycle metabolites are expected to be the biomarkers for cerebrovascular diseases. However, the effects of circulating urea cycle metabolites on the risk of MMD and its subcategories remain unclear. The aim of this study was to prospectively investigate the association between plasma urea cycle metabolites and the risk of MMD and its subcategories.

Methods

We measured plasma urea cycle metabolite levels for 360 adult MMD patients and 89 matched healthy controls. Clinical and laboratory characteristics were obtained from the medical record. The study was conducted from July 2020 to December 2021.

Results

After multivariate adjustment, the risk of MMD increased with each increment in ornithine level (per natural log [ornithine] increment: OR, 3.893; 95% CI, 1.366-11.090). The risk of MMD decreased with each increment in arginine level (per natural log [arginine] increment: OR, 0.109; 95% CI, 0.028-0.427), urea level (per natural log [urea] increment: OR, 0.261; 95% CI, 0.072-0.940), and global arginine bioavailability ratio (GABR) level (per natural log [GABR] increment: OR, 0.189; 95% CI, 0.074-0.484). The addition of plasma arginine (integrated discrimination improvement: 1.76%, p = 0.021) or GABR (integrated discrimination improvement: 1.76%, p = 0.004) to conventional risk factors significantly improved the risk reclassification for MMD.

Conclusion

Plasma ornithine levels are positively associated with the risk of MMD. By contrast, the levels of arginine, urea, and GABR are inversely related to the risk of MMD. Plasma urea cycle metabolites might be potential biomarkers for the risk of MMD.

Physiological and pathophysiological mechanisms of the molecular and cellular biology of angiogenesis and inflammation in moyamoya angiopathy and related vascular diseases

Rationale

The etiology and pathophysiological mechanisms of moyamoya angiopathy (MMA) remain largely unknown. MMA is a progressive, occlusive cerebrovascular disorder characterized by recurrent ischemic and hemorrhagic strokes; with compensatory formation of an abnormal network of perforating blood vessels that creates a collateral circulation; and by aberrant angiogenesis at the base of the brain. Imbalance of angiogenic and vasculogenic mechanisms has been proposed as a potential cause of MMA. Moyamoya vessels suggest that aberrant angiogenic, arteriogenic, and vasculogenic processes may be involved in the pathophysiology of MMA. Circulating endothelial progenitor cells have been hypothesized to contribute to vascular remodeling in MMA. MMA is associated with increased expression of angiogenic factors and proinflammatory molecules. Systemic inflammation may be related to MMA pathogenesis.

Objective

This literature review describes the molecular mechanisms associated with cerebrovascular dysfunction, aberrant angiogenesis, and inflammation in MMA and related cerebrovascular diseases along with treatment strategies and future research perspectives.

Methods and results

References were identified through a systematic computerized search of the medical literature from January 1, 1983, through July 29, 2022, using the PubMed, EMBASE, BIOSIS Previews, CNKI, ISI web of science, and Medline databases and various combinations of the keywords "moyamoya," "angiogenesis," "anastomotic network," "molecular mechanism," "physiology," "pathophysiology," "pathogenesis," "biomarker," "genetics," "signaling pathway," "blood-brain barrier," "endothelial progenitor cells," "endothelial function," "inflammation," "intracranial hemorrhage," and "stroke." Relevant articles and supplemental basic science articles almost exclusively published in English were included. Review of the reference lists of relevant publications for additional sources resulted in 350 publications which met the study inclusion criteria. Detection of growth factors, chemokines, and cytokines in MMA patients suggests the hypothesis of aberrant angiogenesis being involved in MMA pathogenesis. It remains to be ascertained whether these findings are consequences of MMA or are etiological factors of MMA.

Conclusions

MMA is a heterogeneous disorder, comprising various genotypes and phenotypes, with a complex pathophysiology. Additional research may advance our understanding of the pathophysiology involved in aberrant angiogenesis, arterial stenosis, and the formation of moyamoya collaterals and anastomotic networks. Future research will benefit from researching molecular pathophysiologic mechanisms and the correlation of clinical and basic research results.

Moyamoya Disease and Syndrome in Caucasian Patients

Moyamoya disease is a unique cerebrovascular disease characterized by narrowing of the terminal portion of internal carotid arteries and circle of Willis, with consequent development of a network of collateral vessels in response to brain ischemia. Moyamoya vascular pattern can be idiopathic (Moyamoya disease), is more likely to occur in individuals of Asian ascent and in the pediatric age, or is associated with other diseases (Moyamoya syndrome). We present two cases of stroke in young adults, where workup revealed Moyamoya-type vascular changes. The first case report is of a 42-year-old woman presenting with hemorrhagic stroke, with classic angiographic findings of Moyamoya disease, otherwise asymptomatic. The second case concerns a 36-year-old woman admitted with ischemic stroke; besides the typical angiographic pattern of Moyamoya, the patient was diagnosed with antiphospholipid antibody syndrome and Graves' disease, two conditions known to be associated with this vasculopathy. These case reports illustrate the need to consider this entity in the etiological evaluation of ischemic and hemorrhagic cerebrovascular events, even in Western countries, since management and secondary prevention require specific approaches.

RNF213 modulates γ-herpesvirus infection and reactivation via targeting the viral Replication and Transcription Activator

Interferons (IFNs) and the products of interferon-stimulated genes (ISGs) play crucial roles in host defense against virus infections. Although many ISGs have been characterized with respect to their antiviral activity, their target specificities and mechanisms of action remain largely unknown. Kaposi's sarcoma-associated herpesvirus (KSHV) is a gammaherpesvirus that is linked to several human malignancies. Here, we used the genetically and biologically related virus, murine gammaherpesvirus 68 (MHV-68) and screened for ISGs with anti-gammaherpesvirus activities. We found that overexpression of RNF213 dramatically inhibited MHV-68 infection, whereas knockdown of endogenous RNF213 significantly promoted MHV-68 proliferation. Importantly, RNF213 also inhibited KSHV de novo infection, and depletion of RNF213 in the latently KSHV-infected iSLK-219 cell line significantly enhanced lytic reactivation. Mechanistically, we demonstrated that RNF213 targeted the Replication and Transcription Activator (RTA) of both KSHV and MHV-68, and promoted the degradation of RTA protein through the proteasome-dependent pathway. RNF213 directly interacted with RTA and functioned as an E3 ligase to ubiquitinate RTA via K48 linkage. Taken together, we conclude that RNF213 serves as an E3 ligase and inhibits the de novo infection and lytic reactivation of gammaherpesviruses by degrading RTA through the ubiquitin-proteasome pathway.

Circulating Inflammatory Cytokine Associated with Poor Prognosis in Moyamoya Disease: A Prospective Cohort Study

Inflammation is a key factor in the development of moyamoya disease. However, the cytokine distribution in moyamoya disease and its impact on prognosis remain unclear. A total of 204 patients with moyamoya disease were enrolled in this study. The peripheral blood was analyzed for baseline data and cytokines, which included IL-6, IL-1β, IL-2R, IL-8, and TNF-α. Patients with the RNF213 mutation and those without the mutation were compared in terms of their differences in cytokines. A mRS score ≥2 was defined as a poor prognosis, and a mRS score <2 was described as a good prognosis, and differences in cytokines were compared between the two groups. Regression analysis was performed to identify markers affecting prognosis. TNF-α and IL-6 levels were higher in the group without the RNF213 mutation compared to the mutation group. Multivariate stepwise regression analysis indicated that the G3 subgroup of IL-6 and the G4 subgroup of TNF-α were the independent risk factors for adverse prognosis in adults with moyamoya disease (OR 3.678, 95% CI [1.491, 9.074], p = 0.005; OR 2.996, 95% CI [1.180, 7.610], p = 0.021). IL-6 and TNF-α were associated with poor prognosis in adult patients with moyamoya disease.

Filamin A Variant as a Possible Second-Hit Gene Promoting Moyamoya Disease–like Vascular Formation Associated With RNF213 p.R4810K Variant

Background and Objective

The objective of this case report was to identify a second-hit gene that may promote Moyamoya disease (MMD)–like vascular formation in an individual having the RNF213 p.R4810K variant.

Methods

We performed magnetic resonance imaging and genetic analyses of RNF213 and FLNA in a 21-year-old woman, who showed Ehlers-Danlos–like symptoms and developed a first-ever unprovoked seizure, and of her healthy parents.

Results

We identified bilateral periventricular nodular heterotopia (PNH) as the cause of seizures and MMD-like vascular formation in the patient. The patient had the RNF213 p.R4810K variant. Exome analysis identified c.4868delG in the X-linked FLNA gene encoding filamin A p.G1623V fs*41, which could explain PNH and Ehlers-Danlos–like symptoms. Her mother had the same FLNA variant and had asymptomatic bilateral PNH, whereas her father had the RNF213 variant and had normal cerebrovascular structure.

Discussion

The family study suggested that the FLNA variant promoted MMD-like vascular formation in a patient having the RNF213 variant, while the RNF213 variant amplified the phenotypic changes elicited by the FLNA abnormality. Collectively, we identified a gene abnormality in filamin A, a target of RNF213-mediated proteasomal degradation, that may promote MMD-like vascular formation as a possible second-hit gene in individuals having the RNF213 p.R4810K variant.

Circulating choline pathway nutrients and risk of moyamoya disease

Background

Circulating choline pathway nutrients play a critical role in first stroke and recurrent stroke. However, there is limited information available on the effects of choline pathway nutrients on the risk of moyamoya disease (MMD) and its subtypes. We investigated the association between circulating choline and betaine and the incident risk of MMD and its subtypes.

Methods

The case-control study enrolled 385 patients with MMD [i.e., 110 transient ischemic attack (TIA)-type MMD, 157 infarction-type MMD, and 118 hemorrhagic-type MMD] and 89 matched healthy controls.

Results

Serum choline and betaine were inversely related to the risk of MMD and its subtypes. The risk of MMD was decreased with each increment in choline level [per 1 μmol increase: odds ratio (OR), 0.756; 95% CI, 0.678–0.843] and betaine level (per 1 μmol increase: OR, 0.952; 95% CI, 0.932–0.972), respectively. When choline and betaine were assessed as quartiles, compared with the lowest quartile of serum choline and betaine levels, those in the highest quartile had a significantly decreased risk of MMD (choline, Q4 vs. Q1: OR, 0.023; 95% CI, 0.005–0.118; betaine, Q4 vs. Q1: OR, 0.058; 95% CI, 0.018–0.184).

Conclusions

Serum choline and betaine were associated with the decreased risk of MMD and its subtypes.

Bioinformatics Strategies to Identify Shared Molecular Biomarkers That Link Ischemic Stroke and Moyamoya Disease with Glioblastoma

Expanding data suggest that glioblastoma is accountable for the growing prevalence of various forms of stroke formation, such as ischemic stroke and moyamoya disease. However, the underlying deterministic details are still unspecified. Bioinformatics approaches are designed to investigate the relationships between two pathogens as well as fill this study void. Glioblastoma is a form of cancer that typically occurs in the brain or spinal cord and is highly destructive. A stroke occurs when a brain region starts to lose blood circulation and prevents functioning. Moyamoya disorder is a recurrent and recurring arterial disorder of the brain. To begin, adequate gene expression datasets on glioblastoma, ischemic stroke, and moyamoya disease were gathered from various repositories. Then, the association between glioblastoma, ischemic stroke, and moyamoya was established using the existing pipelines. The framework was developed as a generalized workflow to allow for the aggregation of transcriptomic gene expression across specific tissue; Gene Ontology (GO) and biological pathway, as well as the validation of such data, are carried out using enrichment studies such as protein-protein interaction and gold benchmark databases. The results contribute to a more profound knowledge of the disease mechanisms and unveil the projected correlations among the diseases.

Experimental Animal Models for Moyamoya Disease: A Species-Oriented Scoping Review

Moyamoya disease (MMD) is a rare cerebrovascular disease characterized by progressive stenosis of large intracranial arteries and a hazy network of basal collaterals called moyamoya vessels. The etiology and pathogenesis of MMD are still obscure. The biggest obstacles in the basic research of MMD are difficulty in obtaining specimens and the lack of an animal model. It is necessary to use appropriate and rationally designed animal models for the correct evaluation. Several animal models and methods have been developed to produce an effective MMD model, such as zebrafish, mice and rats, rabbits, primates, felines, canines, and peripheral blood cells, each with advantages and disadvantages. There are three mechanisms for developing animal models, including genetic, immunological/inflammatory, and ischemic animal models. This review aims to analyze the characteristics of currently available models, providing an overview of the animal models framework and the convenience of selecting model types for MMD research. It will be a great benefit to identify strategies for future model generations.

Moyamoya Disease Associated with a Deficiency of Complement Component 6

OBJECTIVES

Complement component 6 (C6) deficiency is a very rare genetic defect that leads to significantly diminished synthesis, secretion, or function of C6. In the current report, we demonstrate a previously undescribed, homozygous missense mutation in exon 17 of the C6 gene (c.2545A>G p.Arg849Gly) in a 35-year-old Japanese woman with moyamoya disease and extremely low levels of CH50 (<7.0 U/mL).

MATERIALS AND METHODS

The complement gene analysis using hybridization capture-based next generation sequencing was performed. CH50 was determined in patient's plasma mixed with plasma from a healthy donor or purified human C6 protein. Western blot was performed on patient's plasma using polyclonal antibodies against C6, with healthy donor's plasma and purified human C6 protein as positive controls while C6-depleted human serum as a negative control. The carriage of ring finger protein 213 variant (c.14576G>A p.Arg4859Lys), a susceptibility gene for moyamoya disease, was examined by direct sequencing.

RESULTS

CH50 mixing test clearly showed a deficiency pattern, being rescued by addition of only 1% healthy donor's plasma or 1 μg/mL purified human C6 protein (1/50-1/100 of physiological concentration). Western blot revealed the absence of C6 protein in the patient's plasma, confirming a quantitative deficiency of C6. The ring finger protein 213 variant was not detected.

CONCLUSIONS

Our data implies that unrecognized complement deficiencies would be harbored in cerebrovascular diseases with unknown etiologies.

Genetic determinants of intracranial large artery stenosis in the northern Manhattan study

BACKGROUND

Intracranial stenosis is one of the most common causes of stroke worldwide. Several single nucleotide polymorphisms have been associated with intracranial atherosclerosis, which is inferred to be the most common underlying cause of intracranial large artery stenosis (ILAS). We previously reviewed known genetic variants related to ILAS in predominantly Asian cohorts, but their prevalence and role in ILAS among western multiethnic populations are uncertain.

METHODS

We leveraged existing imaging and genetic data from the Northern Manhattan Study, a multiethnic prospective cohort study. Based on literature review, we selected adiponectin Q (ADIPOQ) rs2241767 and rs182052, ring finger protein 213 (RNF213) rs112735431, apolipoprotein E (APOE) rs429358, phosphodiesterase 4D (PDE4D) rs2910829, lipoprotein lipase (LPL) rs320, and aldosterone synthase (CYP11B2) rs1799998 variants as candidates to explore. We defined ILAS as luminal stenosis >50% in any intracranial large artery using time-of-flight magnetic resonance angiography (MRA).

RESULTS

We included 1109 participants (mean age 70 ± 9 years, 70% Hispanic, 60% women) in this study. ILAS was identified in 81 (7%) NOMAS participants. Logistic regression analyses adjusted for age, sex, principal components, and vascular risk factors showed ILAS prevalence associated with CYP11B2 rs1799998 under the dominant model (OR = 0.56, 95%CI: 0.35-0.89) and LPL rs320 heterozygote genotype (OR = 1.68, 95%CI: 1.05-2.71). The genotype distributions of ADIPOQ rs2241767 and rs182052, APOE rs429358 and CYP11B2 rs1799998 variants were significantly different among non-Hispanic white and Black, and Hispanic groups. When participants were further stratified by race/ethnicity, the estimates were consistent for CYP11B2 rs1799998 across race/ethnic groups but not for LPL rs320.

CONCLUSION

The CYP11B2 rs1799998 variant may be a protective genetic factor for ILAS across race/ethnic groups, but the risk of ILAS associated with LPL rs320 varies by race/ethnic group. Further functional studies may help elucidate the role that these variants play in the pathophysiology of ILAS.

Neurocognitive Profiles of Caucasian Moyamoya Disease Patients in Greece: A Case Series

The impact of Moyamoya Disease (MMD) on cognition inadult Caucasian patients has not yet been thoroughly investigated. The current study is the first to present detailed neuropsychological data on a series of Greek patients with MMD. A group of eight patients was assessed with an extensive neuropsychological battery, including measures of episodic memory, working memory, executive functions, language, and social cognition. The results indicated that MMD may be characterized by a trichotomous neurocognitive profile, characterized by prominent impairment in working memory, executive functions, and social cognition. Overall, we stress the need for a thorough cognitive evaluation of MMD patients and further highlight the potential importance of social cognition in this particular disease. Possible associations between the three impaired cognitive domains in our group are also discussed.

A Magnetic Resonance Angiography-Based Study Comparing Machine Learning and Clinical Evaluation: Screening Intracranial Regions Associated with the Hemorrhagic Stroke of Adult Moyamoya Disease

OBJECTIVES

Moyamoya disease patients with hemorrhagic stroke usually have a poor prognosis. This study aimed to determine whether hemorrhagic moyamoya disease could be distinguished from MRA images using transfer deep learning and to screen potential regions that contain rich distinguishing information from MRA images in moyamoya disease.

MATERIALS AND METHODS

A total of 116 adult patients with bilateral moyamoya diseases suffering from hemorrhagic or ischemia complications were retrospectively screened. Based on original MRA images at the level of the basal cistern, basal ganglia, and centrum semiovale, we adopted the pretrained ResNet18 to build three models for differentiating hemorrhagic moyamoya disease. Grad-CAM was applied to visualize the regions of interest.

RESULTS

For the test set, the accuracies of model differentiation in the basal cistern, basal ganglia, and centrum semiovale were 93.3%, 91.5%, and 86.4%, respectively. Visualization of the regions of interest demonstrated that the models focused on the deep and periventricular white matter and abnormal collateral vessels in hemorrhagic moyamoya disease.

CONCLUSION

A transfer learning model based on MRA images of the basal cistern and basal ganglia showed a good ability to differentiate between patients with hemorrhagic moyamoya disease and those with ischemic moyamoya disease. The deep and periventricular white matter and collateral vessels at the level of the basal cistern and basal ganglia may contain rich distinguishing information.

Targeted metabolomics analysis of serum amino acid profiles in patients with Moyamoya disease

Amino acids are one of the main metabolites in the body, and provide energy for the body and brain. The purpose of this study is to provide a profile of amino acid changes in the serum of patients with Moyamoya disease (MMD) and identify potential disease biomarkers. In this paper, we quantitatively determined the serum amino acid metabolic profiles of 43 MMD patients and 42 healthy controls (HCs). T test, multivariate statistical analysis, and receiver operating characteristic (ROC) curve analysis were used to identify candidate markers. Thirty-nine amino acids were quantified, and 12 amino acid levels differed significantly between the MMD patients and HCs. Moreover, based on ROC curve analysis, four amino acid (L-methionine, L-glutamic acid, β-alanine and o-phosphoserine) biomarkers showed high sensitivity and specificity (AUC > 0.90), and showed the best sensitivity and specificity in MetaboAnalyst 5.0 using binary logistic regression analysis. We have provided serum amino acid metabolic profiles of MMD patients, and identified four potential biomarkers which may both provide clinicians with an objective diagnostic method for early detection of MMD and further our understanding of MMD pathogenesis.

RNF213 gene silencing upregulates transforming growth factor β1 expression in bone marrow-derived mesenchymal stem cells and is involved in the onset of Moyamoya disease

Moyamoya disease (MMD) is a chronic and progressive cerebrovascular occlusion disease, the precise etiology of which is poorly understood. Ring finger protein 213 (RNF213) has been previously identified as a susceptibility gene that serves an important role in angiogenesis, where it has been shown to be closely associated with the onset of MMD. Patients with MMD exhibit increased expression levels of various pro-inflammatory molecules and angiogenic factors. Under certain conditions, bone marrow mesenchymal stem cells (BMSCs) have the ability to differentiate to form neuron-like and microglia-like cells. In the present study, a total of 40 MMD patients and 40 healthy individuals were enrolled. ELISA assays revealed that the expression of serum vascular endothelial growth factor (VEGF) and transforming growth factor β1 (TGF-β1) were higher than that in healthy controls. Furthermore, rat BMSCs (rBMSCs) were isolated and cultured using the whole bone marrow adherence method, which were then phenotyped using flow cytometry. Osteogenic and adipogenic differentiation were determined by using Alizarin red and oil red O staining, respectively. RNF213 was knocked-down using a lentivirus-mediated short hairpin RNA system in passage three rBMSCs, and successful transfection of the RNF213 was confirmed by RT-qPCR and fluorescence imaging. The expression levels of VEGF and TGF-β1 in these rBMSCs were measured on days 7 and 14, respectively. The results demonstrated that RNF213 knockdown upregulated TGF-β1 at both protein and mRNA levels, but did not exert any effect on VEGF gene expression. In conclusion, these findings suggested that that RNF213 knockdown may contribute to aberrant TGF-β1 expression via a pathway that remains to be unidentified, indicating that quantitative changes in RNF213 gene expression may serve an important role in the pathogenesis of MMD.

Hypoxic-ischemic injury causes functional and structural neurovascular degeneration in the juvenile mouse retina

Ischemic stroke is a major cause of long-term disabilities, including vision loss. Neuronal and blood vessel maturation can affect the susceptibility of and outcome after ischemic stroke. Although we recently reported that exposure of neonatal mice to hypoxia–ischemia (HI) severely compromises the integrity of the retinal neurovasculature, it is not known whether juvenile mice are similarly impacted. Here we examined the effect of HI injury in juvenile mice on retinal structure and function, in particular the susceptibility of retinal neurons and blood vessels to HI damage. Our studies demonstrated that the retina suffered from functional and structural injuries, including reduced b-wave, thinning of the inner retinal layers, macroglial remodeling, and deterioration of the vasculature. The degeneration of the retinal vasculature associated with HI resulted in a significant decrease in the numbers of pericytes and endothelial cells as well as an increase in capillary loss. Taken together, these findings suggest a need for juveniles suffering from ischemic stroke to be monitored for changes in retinal functional and structural integrity. Thus, there is an emergent need for developing therapeutic approaches to prevent and reverse retinal neurovascular dysfunction with exposure to ischemic stroke.

Development and Validation of a Nomogram to Predict the Individual Future Stroke Risk for Adult Patients With Moyamoya Disease: A Multicenter Retrospective Cohort Study in China

Background: Studies exploring the predictive performance of major risk factors associated with future stroke events are insufficient, and a useful tool to predict individual risk is not available. Therefore, personalized advice for preventing future stroke in patients with moyamoya disease (MMD) cannot provide evidence-based recommendations. The aim of this study was to develop a novel nomogram with reliable validity to predict the individual risk of future stroke for adult MMD patients.

Methods: This study included 450 patients from seven medical centers between January 2013 and December 2018. Follow-ups were performed via clinical visits and/or telephone interviews from initial discharge to December 2019. The cohort was randomly assigned to a training set (2/3, n = 300) for nomogram development and a test set (1/3, n = 150) for external validation. The Kaplan-Meier analyses and receiver operating characteristic (ROC) curves were applied to assess the clinical benefits of this nomogram.

Results: Diabetes mellitus, a family history of MMD, a past history of stroke or transient ischemic attack, clinical manifestation, and treatment were identified as major risk factors via the least absolute shrinkage and selection operator (LASSO) method. A nomogram including these predictors was established via a multivariate Cox regression model, which displayed excellent discrimination [Harrell's concordance index (C-index), 0.85; 95% confidence interval (CI): 0.75–0.96] and calibration. In the external validation, the nomogram was found to have good discrimination (C-index, 0.81; 95% CI: 0.68–0.94) and calibration. In the subgroup analysis, this predictive nomogram also showed great performance in both ischemic-type (C-index, 0.90; 95% CI: 0.77–1.00) and hemorrhagic-type MMD (C-index, 0.72; 95% CI: 0.61–0.83). Furthermore, the nomogram was shown to have potential in clinical practice through Kaplan-Meier analyses and ROC curves.

Conclusions: We developed a novel nomogram incorporating several clinical characteristics with relatively good accuracy, which may have considerable potential for evaluating individual future stroke risk and providing useful management recommendations for adult patients with MMD in clinical practice.

Genetic and Proteomic Contributions to the Pathophysiology of Moyamoya Angiopathy and Related Vascular Diseases

RATIONALE

This literature review describes the pathophysiological mechanisms of the current classes of proteins, cells, genes, and signaling pathways relevant to moyamoya angiopathy (MA), along with future research directions and implementation of current knowledge in clinical practice.

OBJECTIVE

This article is intended for physicians diagnosing, treating, and researching MA.

METHODS AND RESULTS

References were identified using a PubMed/Medline systematic computerized search of the medical literature from January 1, 1957, through August 4, 2020, conducted by the authors, using the key words and various combinations of the key words "moyamoya disease," "moyamoya syndrome," "biomarker," "proteome," "genetics," "stroke," "angiogenesis," "cerebral arteriopathy," "pathophysiology," and "etiology." Relevant articles and supplemental basic science articles published in English were included. Intimal hyperplasia, medial thinning, irregular elastic lamina, and creation of moyamoya vessels are the end pathologies of many distinct molecular and genetic processes. Currently, 8 primary classes of proteins are implicated in the pathophysiology of MA: gene-mutation products, enzymes, growth factors, transcription factors, adhesion molecules, inflammatory/coagulation peptides, immune-related factors, and novel biomarker candidate proteins. We anticipate that this article will need to be updated in 5 years.

CONCLUSION

It is increasingly apparent that MA encompasses a variety of distinct pathophysiologic conditions. Continued research into biomarkers, genetics, and signaling pathways associated with MA will improve and refine our understanding of moyamoya's complex pathophysiology. Future efforts will benefit from multicenter studies, family-based analyses, comparative trials, and close collaboration between the clinical setting and laboratory research.

RNF213 rare variants and cerebral arteriovenous malformation in a Chinese population

OBJECTIVE

Cerebral arteriovenous malformation (AVM) is characterised by an abnormal tangle of arteries and veins, the rupture of which is a significant portion of the morbidity and mortality cases, especially in young populations. However, the exact risk factors and pathophysiologic mechanisms of AVM remain poorly understood. RNF213 variants have been identified as obvious susceptible factors of several cerebrovascular disorders, such as Moyamoya disease and intracranial aneurysms. Thus, this study aimed to determine whether there is an association between RNF213 rare variants and AVM.

METHODS

The AVM group included 22 patients with AVM. The control group included 1007 samples from the GeneSky in-house database and 208 samples from the 1000 Genome Project of Chinese Han Population. Genomic DNA samples were extracted from the peripheral blood of the AVM patients, and targeted exome sequencing of RNF213 was performed to assess the existence of low-frequency or rare variants. Sanger sequencing was performed to validate the identified variants. Logistic regression analysis was performed to calculate the odds ratios (ORs) and 95 % confidence intervals (CIs) of the candidate variants and risk of AVM. Statistical analyses were performed using SPSS version 21.0.

RESULTS

The RNF213 c.10997T>C variant (amino acid mutation p.M3666T, NM_001256071) was observed in two AVM patients after filtration. It was significantly associated with AVM in the Chinese population (ORs, 10.30 and 25.08; 95 %; CIs, 1.38-77.10 and 4.34-144.90 compared with 1000 Genome Project of Chinese Han Population and GeneSky in-house database, respectively).

CONCLUSION

Rare variants of RNF213 are associated with AVM in the Chinese population, suggesting the important role of RNF213 in AVM. Further studies are needed to verify these findings.

Association of genetic variants of RNF213 with ischemic stroke risk in Koreans

BACKGROUND

Large artery disease (LAD), cardioembolism (CE), and small vessel disease (SVD) are well-established causes of ischemic stroke. Although a founder variant of RNF213 has been regarded a genetic susceptibility for Moyamoya disease (MMD) and certain types of intracranial atherosclerotic stenosis (ICAS), correlations between RNF213 variants and ischemic stroke with SVD remain largely unknown.

OBJECTIVES

This study aimed to characterize the associations of four RNF213 polymorphisms (4448G>A, 4810G>A, 4863G>A, and 4950G>A) with ischemic stroke subtypes in Koreans.

METHODS

Genetic data from 529 stroke patients were analyzed and compared to 424 age- and sex-matched controls. Genetic variants of RNF213, as obtained from the Human Gene Mutation Database, were analyzed in the study subjects using the polymerase chain reaction restriction fragment length polymorphism assay. We investigated four single-nucleotide polymorphisms of RNF213 to elucidate their association with ischemic stroke [LAD, (n = 192), SVD (n = 145) and CE (n = 51)].

RESULTS

The RNF213 4950G>A genotype was observed more frequently in cerebral stroke patients and was more strongly associated with SVD than LAD (P = 0.014). RNF213 4448/4950 in combination with G-A was higher in SVD patients. However, the RNF213 4863/4950 allele combination was associated with increased risk of SVD and LAD. These results confirmed that RNF213 4950GA+AA variants were more frequent in ischemic stroke, especially in SVD, and that RNF213 G-G-G-A and G-G-G-A (4448/4810/4863/4950) haplotype sequences play a role in LAD and CE as well as SVD.

CONCLUSIONS

Our data reported that the RNF213 4950G>A genotypes and several RNF213 (4448/4810/4863/4950) haplotypes were associated with ischemic stroke in Koreans.

Pathological Circulating Factors in Moyamoya Disease

Moyamoya disease (MMD) is a cerebrovascular disease that presents with vascular stenosis and a hazy network of collateral formations in angiography. However, the detailed pathogenic pathway remains unknown. Studies have indicated that in addition to variations in the of genetic factor RNF213, unusual circulating angiogenetic factors observed in patients with MMD may play a critical role in producing “Moyamoya vessels”. Circulating angiogenetic factors, such as growth factors, vascular progenitor cells, cytokines, inflammatory factors, and other circulating proteins, could promote intimal hyperplasia in vessels and excessive collateral formation with defect structures through endothelial hyperplasia, smooth muscle migration, and atypical neovascularization. This study summarizes the hypothesized pathophysiology of how these circulating factors affect MMD and the interactive modulation between them.

New insights into TNFα/PTP1B and PPARγ pathway through RNF213- a link between inflammation, obesity, insulin resistance, and Moyamoya disease

Diabetic patients are always at a higher risk of ischemic diseases like coronary artery diseases. One such ischemic carotid artery disease is Moyamoya disease (MMD) associated with diabetes Type I and II, but the causality was unclear. Ring Finger Protein 213 (RNF213) is the major susceptible gene for MMD. To understand the association between diabetes mellitus and MMD we chose the major players from both of the anomalies: insulin and RNF213. But before establishing the role of RNF213 in the insulin-regulating pathway we had to understand the involvement of RNF213 within different biological systems. For this, we have adopted a preliminary computational approach to find the prominent interactions of RNF213. Our first objective was to construct an interactome for RNF213. We have analyzed several curated databases and adapted a list of RNF213 interacting partners to develop its interactome. Then to understand the involvement of this interactome in biological functions we have analyzed major biological pathways, biological processes, and prominent clusters related to this interactome through a computational approach. Then to develop a pathway that might give clues for RNF213 involvement in the insulin regulatory pathway we have validated the intercluster and intracluster predictions and identified a regulatory pathway for RNF213. RNF213 interactome was observed to be involved in adaptive immunity with 4 major clusters; one of the clusters involved TNFα. The immune system involves several pathways, and therefore at this point, we have chosen an event-based strategy to obtain an explicit target. Immunity is mediated by pro-inflammatory cytokines like TNFα. TNFα-mediated inflammation, obesity, and insulin resistance are associated. Therefore we chose to explore the role of RNF213 in TNFα-mediated inflammation in macrophages and inflammation-mediated insulin-resistance in adipocytes. We have observed an enhancement of RNF213 gene expression by LPS mediated pro-inflammatory stimuli and suppression by PPARγ-mediated anti-inflammatory, insulin-sensitizing stimuli in macrophages, and also in adipocytes. Administration of the pro-inflammatory cytokine TNFα was able to impede the reduction in RNF213 expression during adipogenesis and this effect was observed to be mediated by PTP1B. Inactivation of PTP1B abolished RNF213 expression which in turn enhanced the adipogenesis process through enhanced PPARγ. Constitutive expression of RNF213 suppressed the adipocyte differentiation by the inhibition of PPARγ. We could show the regulation of RNF213 by TNFα/PTP1B pathway and PPARγ. The constitutive expression of RNF213 during adipogenesis appears to be an adipostatic measure that obese patients acquire to inhibit further adipogenesis. This is verified in silico by analyzing the gene expression data obtained from the Gene Expression Omnibus database, which showed a higher expression of RNF213 in adipose tissue samples of obese people. Overall this study gives new insights into the TNFα-mediated pathway in adipogenesis and suggests the role of RNF213 in adipogenesis via this pathway.

Flow-augmentation bypass for moyamoya disease

Moyamoya disease (MMD) is a chronic, occlusive cerebrovascular disease with unknown etiology, which is characterized by progressive steno-occlusive changes at the terminal portion of the internal carotid artery and an abnormal vascular network formation at the base of the brain. MMD has an intrinsic temporal nature to attempt a gradual conversion of the vascular supply for the brain from intracranial/internal carotid (IC) system to extracranial/external carotid (EC) system, so called "IC-EC conversion." Compatible cerebrovascular angio-architecture could be found in association with a variety of conditions such as neuro-fibromatosis type-1, Down's syndrome and cranial irradiation, which is called as moyamoya syndrome, akin/quasi MMD, or secondary MMD. Diagnosis of moyamoya vasculopathy, either idiopathic or secondary, is clinically important because flow-augmentation bypass is markedly beneficial for this entity to prevent cerebral ischemic attack by improving cerebral blood flow. Moreover, recent evidence indicated that flow-augmentation bypass could prevent re-bleeding in hemorrhagic MMD patients. Based on these backgrounds, there is a worldwide increase in the number of MMD patients undergoing bypass surgery. We sought to demonstrate our standard surgical procedure of superficial temporal artery-middle cerebral artery bypass with indirect pial synangiosis for MMD and its technical pitfall. We also discuss the intrinsic peri-operative hemodynamics of MMD after bypass surgery, including local cerebral hyper-perfusion and characteristic hemodynamic ischemia caused by watershed shift phenomenon. The aim of this review article is to understand the basic pathology of MMD, which is essential for complication avoidance while conducting flow-augmentation bypass for MMD.

Association of single nucleotide polymorphisms of MTHFR, TCN2, RNF213 with susceptibility to hypertension and blood pressure

Methylenetetrahydrofolate reductase gene (MTHFR), transcobalaminII (TCN2) and ring finger protein 213 (RNF213) are related to homocysteine (Hcy) level and are of great significance for hypertension. We aimed to evaluate the associations of MTHFR (rs1801133, rs1801131, rs9651118), TCN2 (rs117353193) and RNF213 (rs9916351) with hypertension and blood pressure (BP). A total of 953 patients with hypertension and 1103 controls were enrolled. Genotyping was performed by Taqman. Logistic regression analysis indicated that A allele of TCN2 rs117353193 under the dominant model had a significantly protective effect (P=0.045) after adjustment, which showed that AA+GA genotype has a lower risk than GG. Additionally, the average diastolic BP (DBP) (P=0.044) and mean arterial pressure (MAP) (P=0.035) levels were significantly different between genotypes of RNF213 rs9916351. Further pairwise comparison showed that the average systolic BP (SBP) level of the TT genotype carriers were significantly higher than in CC (P=0.024), and the average DBP and MAP levels of the TT genotype carriers were higher than in CT (P=0.044, P=0.012, respectively) and CC (P=0.048, P=0.010, respectively). In the recessive model, the average SBP (P=0.043), DBP (P=0.018) and MAP (P=0.017) levels with the TT genotype carriers were significantly higher than in CT+CC. Multiple linear regression analysis suggested that RNF213 rs9916351 in the recessive model had significant effects on SBP (P=0.025), DBP (P=0.017) and MAP (P=0.010) as a risk factor. However, no associations were observed between MTHFR and hypertension. TCN2 rs117353193 might serve as a protective factor in hypertension, and RNF213 rs9916351 might be a risk factor that is linked to increase BP level in Northeast Chinese population.

Association between bilateral postoperative neoangiogenesis in patients with moyamoya disease

OBJECTIVE

The research on neoangiogenesis after indirect bypass for moyamoya disease (MMD) evaluated by using digital subtraction angiography (DSA) is limited. Our study objective was to investigate association of bilateral postoperative neoangiogenesis in patients with MMD.

PATIENTS AND METHODS

All consecutive inpatients with MMD who received bilateral indirect bypass at Beijing Tiantan Hospital, Capital Medical University from January 2011 through December 2017 were screened. Bilateral neoangiogenesis was evaluated on lateral views and anteroposterior views by using DSA.

RESULTS

Twenty-two patients (44 hemispheres) were included in this study. After a median 7.5 months DSA follow-up, on lateral views, 9 (40.9 %) hemispheres had grade A, 8 (36.4 %) hemispheres had grade B, and 5 (22.7 %) hemispheres had grade C after bypass on one side; 11 (50.0 %) hemispheres had grade A, 7 (31.8 %) hemispheres had grade B, and 4 (18.2 %) hemispheres had grade C after bypass on contralateral side. On anteroposterior views of ECA, 2 (9.1 %) hemispheres had level 0, 3 (13.6 %) had level 1, 6 (27.3 %) had level 2, and 11 (50.0 %) had level 3 after bypass on one side; 2 (9.1 %) hemispheres had level 0, 2 (9.1 %) had level 1, 6 (27.3 %) had level 2, and 12 (54.6 %) had level 3 after bypass on contralateral side. There was strong association between bilateral postoperative neoangiogenesis on lateral views (r_s = 0.770; p = 0.000) and the anteroposterior views (r_s = 0.548; p = 0.008).

CONCLUSIONS

There was strong association between bilateral postoperative neoangiogenesis. Postoperative neoangiogenesis on one side might predict the postoperative neoangiogenesis on the other side.

Identification of Genetic Factors Underlying the Association between Sodium Intake Habits and Hypertension Risk

The role of sodium in hypertension remains unresolved. Although genetic factors have a significant impact on high blood pressure, studies comparing genetic susceptibility between people with low and high sodium diets are lacking. We aimed to investigate the genetic variations related to hypertension according to sodium intake habits in a large Korean population-based study. Data for a total of 57,363 participants in the Korean Genome and Epidemiology Study Health Examination were analyzed. Sodium intake was measured by a semi-quantitative food frequency questionnaire. We classified participants according to sodium intake being less than or greater than 2 g/day. We used logistic regression to test single-marker variants for genetic association with a diagnosis of hypertension, adjusting for age, sex, body mass index, exercise, alcohol, smoking, potassium intake, principal components 1, and principal components 2. Significant associations were defined as p < 5 × 10-8. In participants whose sodium intake was greater than 2 g/day, chromosome 6 open reading frame 10 (C6orf10)-human leukocyte antigen (HLA)-DQB1 rs6913309, ring finger protein (RNF)213 rs112735431, glycosylphosphatidylinositol anchored molecule-like (GML)- cytochrome P450 family 11 subfamily B member 1(CYP11B1) rs3819496, myosin light chain 2 (MYL2)-cut like homeobox 2 (CUX2) rs12229654, and jagged1 (JAG1) rs1887320 were significantly associated with hypertension. In participants whose intake was less than 2 g/day, echinoderm microtubule-associated protein-like 6(EML6) rs67617923 was significantly associated with hypertension. Genetic susceptibility associated with hypertension differed according to sodium intake. Identifying gene variants that contribute to the dependence of hypertension on sodium intake status could make possible more individualized nutritional recommendations for preventing cardiovascular diseases.

Familial Risk for Moyamoya Disease Among First-Degree Relatives, Based on a Population-Based Aggregation Study in Korea

BACKGROUND AND PURPOSE

Genetic factors have been known to play a role in the etiology of moyamoya disease (MMD); however, population-level studies quantifying familial risk estimates are unavailable. We aimed to quantify familial incidence and risk for MMD in first-degree relatives (FDR) in the general population of Korea.

METHODS

By using the Korean National Health Insurance database which has complete population coverage and confirmed FDR information, we constructed a cohort of 21 940 795 study subjects constituting 12 million families with blood-related FDR and followed them for a familial occurrence of MMD from 2002 to 2017. Incidence risk ratios were calculated as MMD incidence in individuals with affected FDR compared with those without affected FDR, according to age, sex, and family relationships.

RESULTS

Among total study subjects, there were 22 459 individuals with affected FDR, of whom 712 familial cases developed MMD with an incidence of 21.8/10⁴ person-years. Overall, the familial risk for MMD was 132-fold higher in individuals with versus without affected FDR. Familial risk (incidence risk ratio; incidence/10⁴ person-years) increased with the degree of genetic relatedness, being highest in individuals with an affected twin (1254.1; 230.0), followed by a sibling (212.4; 35.6), then mother (87.7; 14.4) and father (62.5; 10.4). Remarkably, there was no disease concordance between spouses. The risks were age-dependent and were particularly high in younger age groups. Familial risks were similar in males and females, and the risk of disease transmission was higher in same-sex parent-offspring and sibling pairs.

CONCLUSIONS

Our study indicates that genetic predisposition is the predominant driver in MMD pathogenesis, with minimal contribution of environmental factors. These results could be utilized to direct future genetic studies and clinical risk counseling.

Different subtypes of collateral vessels in hemorrhagic moyamoya disease with p.R4810K variant

Background

The aim of this study was to investigate the hemorrhgic sites and collateral vessels in hemorrhagic MMD with the p.R4810K variant.

Methods

Hemorrhage sites were classified as either anterior or posterior. Collateral vessels were classified into three subtypes according to origin: lenticulostriate anastomosis, thalamic anastomosis, and choroidal anastomosis. Hemorrhage sites and collateral vessels were compared between patients with wild-type p.R4810K variant (GG) and patients with heterozygous p.R4810K variant (GA) after 1:1 propensity score matching.

Results

A total of 130 hemorrhagic MMD patients were included in present study, 21 pairs (42 hemorrhagic hemispheres) were obtained after 1:1 propensity score. In GA group, 16 hemispheres (76.2%) presented anterior hemorrhage, and 5 hemispheres (23.8%) presented with posterior hemorrhage. In GG group, 13 hemispheres (61.9%) presented anterior hemorrhage, and 8 hemispheres (38.1%) presented with posterior hemorrhage. No significant differences were found in hemorrhagic sites between two matched groups (P > 0.05). Of 21 hemispheres in GA group, 10 (47.6%) exhibited lenticulostriate anastomosis, 6 (28.6%) thalamic anastomosis, and 6 (28.6%) choroidal anastomosis. Of 21 hemispheres in GG group, 3 (14.3%) exhibited lenticulostriate anastomosis, 5 (23.8%) thalamic anastomosis, and 9 (42.9%) choroidal anastomosis. There was significant difference in lenticulostriate anastomosis between two matched groups (P = 0.045). After adjustment the age, sex, and PCA involvement, we found that lenticulostriate anastomosis was associated with p.R4810K variant (OR, 5.995; 95% CI, 1.296–27.737; P = 0.022).

Conclusion

Lenticulostriate anastomosis might be associated with p.R4810K variant. Whereas hemorrhagic sites, thalamic anastomosis, and choroidal anastomosis might not be associted withp.R4810K variant.

RNF213 gene polymorphism rs9916351 and rs8074015 significantly associated with moyamoya disease in Chinese population

Background

Gene polymorphism especially Ring Finger Protein 213 (RNF213) p.R4810K is one of the main cause of moyamoya disease (MMD) in Asian populations, especially among Japanese people. However, missense mutation may not explain the reduced frequency of MMD in Chinese patients. We performed a hospital based case-control study in a Chinese population to elucidate the possible underlying reasons.

Methods

Five gene polymorphism loci, namely, rs35692831, rs9916351, rs9913636, rs8074015 and rs112735431, were included. A total of 98 patients and 114 healthy controls were enrolled in the study. Genomic DNA was genotyped by Mass Array methods.

Results

A significant difference was observed between patients and healthy controls in rs9916351, rs9913636, and rs8074015 loci under three genotypes and allelic models (P<0.01). Logistic regression analysis revealed the significant differences under the dominant, recessive and additional model in rs9916351 [odds ratio (OR) =4.173, 95% confidence interval (CI): 2.290-7.606, P<0.001; OR =3.152, 95% CI: 1.585-6.267, P=0.001; OR =0.199, 95% CI: 1.727-3.764, P<0.001; respectively] and rs8074015 (OR =0.359, 95% CI: 0.206-0.627, P<0.001; OR =0.348, 95% CI: 0.148-0.81, P=0.015; OR =0.208, 95% CI: 0.311-0.703, P<0.001; respectively), even adjusting for age and gender. In addition, the haplotype rs9913636-rs8074015 under "GACG" showed significant association with MMD.

Conclusions

Our results had revealed the polymorphism of RNF213 rs9916351 and rs8074015 were significantly associated with MMD especially in Chinese population.

Modifiable Risk Factors Associated With Moyamoya Disease: A Case-Control Study

BACKGROUND AND PURPOSE

The cause of moyamoya disease (MMD) remains unknown. We aimed to investigate the association between modifiable risk factors and MMD in a prospective, case-control study.

METHODS

Clinical and laboratory characteristics were evaluated in consecutively recruited adult patients with MMD and age-matched healthy control individuals. The potential risk factors for MMD were estimated by logistic regression analysis.

RESULTS

Our prospective study included 138 adult patients and 138 healthy control subjects. Logistic regression analyses showed that increased body mass index (odds ratio [OR], 1.121 [95% CI, 1.018-1.234]; P=0.020) and homocysteine (OR, 1.201 [95% CI, 1.081-1.334]; P=0.001) were associated with higher risk of MMD. Whereas increased albumin (OR, 1.043 [95% CI, 1.004-1.082]; P=0.028) and high-density lipoprotein cholesterol (OR, 1.043 [95% CI, 1.004-1.082]; P=0.028) were correlated with a lower risk of MMD. Furthermore, homocysteine (OR, 1.070 [95% CI, 1.010-1.134]; P=0.023) was significantly related to unilateral lesions.

CONCLUSIONS

Increased body mass index and homocysteine were associated with a higher risk of MMD. In contrast, increased albumin and high-density lipoprotein cholesterol were correlated with a lower risk of MMD. Furthermore, increased homocysteine was related to a higher prevalence of unilateral MMD. More attention should be paid to the modifiable risk factors of MMD, as these might help us finding its cause and new therapeutic regimen. Registration: URL: http://www.chictr.org. Unique identifier: ChiCTR2000031412.

Are Genetic Variants Associated with the Location of Cerebral Arterial Lesions in Stroke Patients?

BACKGROUND

Genetic variants may play a role in determining the location of cerebral atherosclerosis. We aimed to investigate the association between RNF213, MMP2, and genetic polymorphisms linked to vascular tortuosity with the location of cerebral arterial atherosclerosis.

METHODS

A prospective case-control study was conducted on patients with ischemic stroke and age- and sex-matched stroke-free controls. The stroke patients were categorized into those with intracranial artery atherosclerosis (ICAS), extracranial artery atherosclerosis (ECAS), and small vessel occlusion (SVO). Six single nucleotide polymorphisms (SNPs) including rs2118181 (FBN1), rs2179357 (SLC2A10), rs1036095 (TGFBR2), rs243865 (MMP2), rs1800470 (TGFB1), and rs112735431 (RNF213) were analyzed with the TaqMan Genotyping Assay, and the distribution of genotypes across groups was compared.

RESULTS

None of the 6 SNPs were associated with stroke on comparing the 449 stroke patients (71 with ECAS, 169 with ICAS, and 209 with SVO) to the 447 controls. In the subgroup analysis, the adjusted odds ratios (aORs) for age and sex indicated a significant association between rs112735431 and ICAS in the allele comparison analysis and in the additive and dominant model analyses. rs112735431 was associated with anterior circulation involvement and increased burden of cerebral atherosclerosis. rs2179357 was significantly associated with ICAS in the recessive model analysis, and rs1800470 was significantly associated with ECAS in the recessive model analysis when compared to controls.

CONCLUSION

rs112735431 was associated with ICAS and increased atherosclerosis burden in Korean stroke patients. Further studies are needed to elucidate the role of rs112735431 and to confirm the association of rs2179357 and rs1800470 with cerebral atherosclerosis.