The Progression of Pathophysiology of Moyamoya Disease

Integrated bulk RNA sequencing and mass cytometry analysis reveal the circulating immune landscape in ischemic and hemorrhagic Moyamoya disease

BACKGROUND

Moyamoya disease (MMD) is increasingly recognized as being influenced by chronic inflammation, with circulating immune cells playing a role in its progression. However, research on the immune characteristics of different MMD subtypes is limited. This study aims to compare the peripheral immune profiles of ischemic and hemorrhagic MMD patients.

METHODS

Peripheral immune profiles were analyzed using transcriptome sequencing and mass cytometry. Data preprocessing was followed by functional and gene set enrichment analyses, as well as the construction of immune-related gene sets and protein-protein interaction networks. High-dimensional data analysis was performed using the PhenoGraph and t-SNE algorithms.

RESULTS

The study involved 9 ischemic and 6 hemorrhagic MMD patients for transcriptome analysis, and 20 ischemic and 16 hemorrhagic patients for mass cytometry. Hemorrhagic MMD patients exhibited upregulated genes associated with inflammation, hypoxia, and bacterial responses and downregulated genes related to immune response regulation. The results of mass cytometry analysis showed that, compared to ischemic MMD, patients with hemorrhagic MMD had reduced CD3 expression levels in T cells and their specific subsets, as well as impaired chemotactic capacity of DPT cells. The function of the B03 subset in B cells was diminished, while the proportion of NK cells increased and that of monocytes decreased. Additionally, the proportions of the D03 and D07 subsets in dendritic cells (DCs) were elevated.

CONCLUSIONS

This study reveals distinct immune profiles in ischemic and hemorrhagic MMD, emphasizing the need for subtype-specific therapeutic strategies.

miR-6760-5p suppresses neoangiogenesis by targeting Yes-associated protein 1 in patients with moyamoya disease undergoing indirect revascularization

OBJECTIVE

The aim of this research was to investigate the specific regulatory role of miR-6760-5p in angiogenesis in moyamoya disease.

METHODS

HUVECs were transfected with miR-6760-5p inhibitor and mimics fragments, then subjected to assays for cell proliferation, migration, and tube formation. Subsequently, downstream target genes of miR-6760-5p were predicted and the protein expression levels of these genes were evaluated. The presence of miR-6760-5p and YAP1 was verified by a dual luciferase reporter gene test, followed by an assessment of the effects of YAP1 and miR-6760-5p on the HUVECs.

RESULTS

Comparatively to the control group, increased expression of miR-6760-5p decreased cell growth, movement, and tube formation. YAP1 gene was discovered as a target controlled by miR-6760-5p, with subsequent investigation confirming YAP1 as a gene regulated by miR-6760-5p. Additionally, miR-6760-5p was found to counteract the angiogenesis-promoting effect of YAP1.

CONCLUSION

The results of this research suggest a possible link between the miR-6760-5p gene found in the cerebrospinal fluid of individuals with moyamoya disease and the process of vascularization in this particular condition. The findings indicate that miR-6760-5p may be a new molecular indicator and potential target for the diagnosis of moyamoya disease.

Clinical Characteristics and Multi-Model Imaging Analysis of Moyamoya Disease: An Observational Study

PURPOSE

Previous studies have lacked a comprehensive analysis of imaging modalities for diagnosing Moyamoya disease (MMD). This study aims to bridge this gap by utilizing multi-modal imaging to provide a more detailed understanding of the clinical and imaging characteristics of MMD.

METHODS

A retrospective analysis was conducted on seventy-eight adult MMD patients enrolled from March 2018 to March 2021. The study focused on clinical features, imaging findings, and treatment outcomes, with a particular emphasis on the comparative efficacy of different imaging modalities.

RESULTS

In this series, clinical manifestations varied depending on the type of MMD, with intracerebral hemorrhage (ICH) being the most common (69.2%), followed by cerebral infarction (25.6%). Imaging techniques provided critical diagnostic insights: magnetic resonance imaging (MRI) demonstrated superior sensitivity over computed tomography (CT) in detecting hemorrhages, whereas computed tomography angiography (CTA) and digital subtraction angiography (DSA) identified intricate vascular lesions, including moyamoya vessels and aneurysms. Notably, cerebral perfusion imaging (CTP) highlighted significant differences in cerebral blood flow and volume between infarction and hemorrhage cases. This comprehensive imaging approach guided varied therapeutic strategies, including bypass surgery in 57 patients and interventional embolization for aneurysms in 14 patients.

CONCLUSION

The authors' findings underscore the critical role of early diagnosis using DSA, whereas highlighting CTA and MRA as valuable noninvasive tools for screening and follow-up. The integration of multi-modal imaging provides a detailed vascular assessment crucial for individualized patient management, facilitating timely interventions and significantly improving clinical outcomes.

Innate Immune Cell Profiling in Peripheral Blood Mononuclear Cells of Patients with Moyamoya Disease

Moyamoya disease (MMD) is a rare cerebrovascular disease characterized by stenosis or occlusion of the internal carotid artery, thus leading to ischaemic and haemorrhagic strokes. Although genetic studies have identified ring finger protein 213 (RNF213) as a susceptibility gene, the low disease penetrance suggests that a secondary trigger, such as infection, may initiate disease onset. This study aimed to characterize the innate immune cell profile of peripheral blood mononuclear cells (PBMCs) of MMD patients via mass cytometry (CyTOF). Blood samples from 10 MMD patients and 10 healthy controls were analysed, with a focus on natural killer (NK) cells, monocytes, and dendritic cells (DCs). The results revealed significant changes in the NK and monocyte subpopulations in MMD patients; specifically, there was a decrease in the CD56dimCD16- NK03 subset and an increase in CD163high classical monocytes, thus indicating compromised microbial defences and heightened inflammation. Additionally, significant changes were observed in DC subpopulations, including an increase in CCR7+ mature DCs and a decrease in CD141+ and CD1c+ DCs. Overactivation of the TLR/MyD88/NF-κB pathway was observed in most innate immune cells, thus indicating its potential role in disease progression. These findings provide novel insights into immune dysfunction in MMD and highlight potential therapeutic targets.

Prognostic value of morphology and hemodynamics in moyamoya disease for long-term outcomes and disease progression

To explore the relationship between morphological and hemodynamic parameters, baseline characteristics, and long-term outcomes in patients with moyamoya disease (MMD) using a computational fluid dynamics model. We retrospectively reviewed 129 patients at Beijing Tiantan hospital between July 2020 and December 2021. Perioperative clinical variables and Suzuki stage were recorded. Logistic regression analysis was employed to identify the risk factors for unfavorable long-term outcomes. The association between morphological, CT perfusion parameters, hemodynamic parameters and the Suzuki stage, clinical variables of MMD was also analyzed. Patients with high relative Wall Shear Stress (rWSS) were older and had more cases with higher Suzuki stage and worse follow-up mRS scores (p < 0.05). High rWSS at the terminal ICA and diabetes mellitus were identified as independent predictors of unfavorable long-term outcomes [OR = 3.039(1.191-7.754), p = 0.020; OR = 3.164(1.141-8.723), p = 0.027, respectively]. ROC analysis demonstrated that predictive models incorporating rWSS improved AUC values, with the highest AUC in Model 2 (AUC = 0.889). High rWSS was significantly associated with future TIA and stroke events (p = 0.032). We speculated that high rWSS and diabetes mellitus were independent risk factors for unfavorable long-term outcomes in patients with MMD. rWSS and morphological parameters are crucial for predicting MMD progression and understanding its pathogenesis.

Understanding external carotid artery collateralisation after cerebral revascularisation in moyamoya disease: insights from quantitative analysis

BACKGROUND

This study aims to quantitatively evaluate collateralisation angiogenesis ratio (CAR) of external carotid artery and intracranial arterial residual volumes (ARV) postcerebral revascularisation in moyamoya disease (MMD) and elucidate the factors influencing external carotid artery collateralisation.

METHODS

The study retrospectively analysed 297 patients diagnosed with MMD who underwent cerebral revascularisation at our University's Hospital, between January 2015 and May 2023. The clinical data, imaging results and surgical specifics for the patients were collected. Using a newly proposed digital subtraction angiography-based evaluation system, the CAR of external carotid artery and the intracranial ARV were evaluated quantitatively following standardised protocols.

RESULTS

The study included 136 male and 161 female patients. The severity of ischaemic (r=-0.297) and haemorrhagic (r=-0.270) MMD, as assessed by the Suzuki stage, demonstrated a significant negative correlation with intracranial ARV (p<0.001). However, no significant correlation was observed between the intracranial ARV and the modified Rankin Scale scores. Patients with fetal-type posterior cerebral arteries exhibited greater intracranial ARV compared with those without (p=0.003). Additionally, a positive correlation was observed between external carotid artery collateralisation and intracranial ARV post-revascularisation (r=0.340, p<0.001). The CAR of external carotid artery following cerebral revascularisation in patients with MMD remained independent correlation of the intracranial ARV (β=0.385, 95% CI (0.921 to 1.669), p<0.001) and Suzuki stage (β=0.211, 95% CI (0.009 to 0.030), p<0.001).

CONCLUSIONS

This study showed a complex association between ARV, the Suzuki stage and the collateralisation of the external carotid artery in patients with MMD who are undergoing revascularisation. These findings provide insights into MMD progression and revascularisation outcomes and may guide clinical decision-making to improve patient care.

Insights into the regulatory role of epigenetics in moyamoya disease: Current advances and future prospectives

Moyamoya disease (MMD) is a progressive steno-occlusive cerebrovascular disorder that predominantly affecting East Asian populations. The intricate interplay of distinct and overlapping mechanisms, including genetic associations such as the RNF213-p.R4810K variant, contributes to the steno-occlusive lesions and moyamoya vessels. However, genetic mutations alone do not fully elucidate the occurrence of MMD, suggesting a potential role for epigenetic factors. Accruing evidence has unveiled the regulatory role of epigenetic markers, including DNA methylation, histone modifications, and non-coding RNAs (ncRNAs), in regulating pivotal cellular and molecular processes implicated in the pathogenesis of MMD by modulating endothelial cells and smooth muscle cells. The profile of these epigenetic markers in cerebral vasculatures and circulation has been determined to identify potential diagnostic biomarkers and therapeutic targets. Furthermore, in vitro studies have demonstrated the multifaceted effects of modulating specific epigenetic markers on MMD pathogenesis. These findings hold great potential for the discovery of novel therapeutic targets, translational studies, and clinical applications. In this review, we comprehensively summarize the current understanding of epigenetic mechanisms, including DNA methylation, histone modifications, and ncRNAs, in the context of MMD. Furthermore, we discuss the potential challenges and opportunities that lie ahead in this rapidly evolving field.

Desmoglein-2 Affects Vascular Function in Moyamoya Disease by Interacting with MMP-9 and Influencing PI3K Signaling

The pathogenesis and development of Moyamoya disease are still unclear. This study aimed to investigate the effect of desmoglein-2 (DSG2) on Moyamoya disease and determine the inhibitory effect of DSG2 in vascular remodeling in Moyamoya disease.RNA sequencing, immunohistochemistry (IHC), and western blotting were used to detect the expression of DSG2 in the superficial temporal artery (STA) tissues of Moyamoya disease. The association between DSG2 and endothelial cells' biological activities was investigated by cell counting kit-8 (CCK-8), migration assay, tube formation assay, flow cytometry with Annexin V-FITC/PI staining, and TUNEL apoptotic cell detection kit. Pathways affected by overexpression or knockdown of DSG2 were identified in endothelial cells.The expression of DSG2 in the STA tissues of Moyamoya disease was lower than that in normal controls. Overexpression of DSG2 inhibits the proliferation and migration but promotes apoptosis in endothelial cells, and low DSG2 levels result in impaired angiogenesis. In addition, there was an interaction between DSG2 and MMP-9, and DSG2 acted through the PI3K signaling in endothelial cells.Our results indicate that DSG2 affects PI3K signaling in vascular endothelial cells, and MMP-9 is involved in DSG2-mediated vascular changes in Moyamoya disease.

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.

High-resolution magnetic resonance vessel wall imaging provides new insights into Moyamoya disease

Moyamoya disease (MMD) is a rare condition that affects the blood vessels of the central nervous system. This cerebrovascular disease is characterized by progressive narrowing and blockage of the internal carotid, middle cerebral, and anterior cerebral arteries, which results in the formation of a compensatory fragile vascular network. Currently, digital subtraction angiography (DSA) is considered the gold standard in diagnosing MMD. However, this diagnostic technique is invasive and may not be suitable for all patients. Hence, non-invasive imaging methods such as computed tomography angiography (CTA) and magnetic resonance angiography (MRA) are often used. However, these methods may have less reliable diagnostic results. Therefore, High-Resolution Magnetic Resonance Vessel Wall Imaging (HR-VWI) has emerged as the most accurate method for observing and analyzing arterial wall structure. It enhances the resolution of arterial walls and enables quantitative and qualitative analysis of plaque, facilitating the identification of atherosclerotic lesions, vascular entrapment, myofibrillar dysplasia, moyamoya vasculopathy, and other related conditions. Consequently, HR-VWI provides a new and more reliable evaluation criterion for diagnosing vascular lesions in patients with Moyamoya disease.

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.

Neuregulin 1 as a potential biomarker for disease progression in moyamoya disease: A case-control study in Chinese population

OBJECTIVE

Moyamoya disease (MMD) is a rare and progressive stenosis of cerebral arteries characterized by abnormally proliferative vasculopathy. Current studies have demonstrated that Neuregulin 1 (NRG1) plays a key role in angiogenesis-related disorders. Thus, the aim of our study is to investigate the serum NRG1 levels and their clinical correlations in MMD patients.

METHODS

In this study, thirty adult patients with MMD and age-gender matched healthy controls were enrolled from our hospital between July 2020 and April 2022. Peripheral blood samples were collected at baseline, and clinical data were obtained from the electronic medical record system. Serum NRG1 concentrations were measured by enzyme-linked immunosorbent assay. Sanger sequencing was applied to detect the RNF213 p.R4810K mutation.

RESULTS

The serum NRG1 levels were significantly higher in MMD patients compared to controls (14.48 ± 10.81 vs.7.54 ± 6.35mmol/L, p < 0.001). No statistical difference in baseline clinical characteristics was found between both groups. Correlation analyses showed that NRG1 levels were positively associated with Suzuki staging (r = 0.4137, p = 0.023) while not related to other clinical features (reduced cerebral blood flow, posterior cerebral artery involvement, bilateral or unilateral steno-occlusive changes). Furthermore, subgroup analysis revealed that MMD patients with the RNF213 p.R4810K mutation presented with significantly higher NRG1 levels than those without the mutation (9.60 ± 0.929 vs. 25.89 ± 4.338 mmol/L, p = 0.001).

CONCLUSIONS

Our study suggests that increased serum NRG1 levels may constitute a characteristic feature of MMD, indicating a potential positive correlation with disease progression and the presence of the RNF213 mutation. This positions NRG1 as a potentially crucial target for further studies aimed at comprehending the pathogenesis of MMD.

Liquid chromatography coupled to mass spectrometry metabolomic analysis of cerebrospinal fluid revealed the metabolic characteristics of moyamoya disease

Objective

Metabolomics has found extensive applications in the field of neurological diseases, significantly contributing to their diagnosis and treatment. However, there has been limited research applying metabolomics to moyamoya disease (MMD). This study aims to investigate and identify differential metabolites associated with MMD.

Methods

We employed a liquid chromatography coupled with mass spectrometry (LC-MS) approach, complemented by univariate and multivariate analyses, to discern metabolic biomarkers in cerebrospinal fluid samples. We then compared these biomarkers between MMD patients and healthy controls (Ctl).

Results

Sixteen patients diagnosed with MMD via cerebral angiography and eight healthy controls were enrolled in this study. Comparative analyses, including univariate and multivariate analyses, correlation studies, heatmaps, Volcano Plots, and KEGG pathway enrichment, were performed between MMD patients and controls. As a result, we identified 129 significant differential metabolites in the cerebrospinal fluid between MMD patients and controls. These metabolic biomarkers are associated with various pathways, with notable involvement in purine and pyrimidine metabolism.

Conclusion

Utilizing an LC-MS-based metabolomics approach holds promise for enhancing the clinical diagnosis of MMD. The identified biomarkers offer potential avenues for the development of novel diagnostic methods for MMD and offer fresh insights into the pathogenesis of the disease.