Identifying novel risk genes in intracranial aneurysm by integrating human proteomes and genetics.

Genome-wide association studies (GWAS) have become increasingly popular for detecting numerous loci associated with intracranial aneurysm (IA), but how these loci function remains unclear. In this study, we employed an integrative analytical pipeline to efficiently transform genetic associations and identify novel genes for IA. Using multidimensional high-throughput data, we integrated proteome-wide association studies (PWAS), transcriptome-wide association studies (TWAS), Mendelian randomization (MR) and Bayesian co-localization analyses to prioritize genes that can increase IA risk by altering their expression and protein abundances in the brain and blood. Moreover, single-cell RNA sequencing (scRNA-seq) of the circle of Willis was performed to enrich filtered genes in cells, and gene set enrichment analysis (GSEA) was conducted for each gene using bulk RNA-seq data for IA. No significant genes with cis-regulated plasma protein levels were proven to be associated with IA. The protein abundances of five genes in the brain were found to be associated with IA. According to cellular enrichment analysis, these five genes were expressed mainly in the endothelium, fibroblasts and vascular smooth muscle cells. Only three genes, CNNM2, GPRIN3 and UFL1, passed MR and Bayesian co-localization analyses. While UFL1 was not validated in confirmation PWAS as it was not profiled, it was validated in TWAS. GSEA suggested these three genes are associated with the cell cycle. In addition, the protein abundance of CNNM2 was found to be associated with IA rupture (based on PWAS, MR and co-localization analyses). Our findings indicated that CNNM2, GPRIN3 and UFL1 (CNNM2 correlated with IA rupture) are potential IA risk genes that may provide a broad hint for future research on possible mechanisms and therapeutic targets for IA.

Activation of BMP4-pSmad1/5 pathway impairs the function of VSMCs in intracranial aneurysms.

Intracranial aneurysms (IAs) are characterized by abnormal dilatation of the cerebral vessels. Vascular smooth muscle cells (VSMCs) are implicated in maintaining vascular homeostasis. Disordered VSMCs are one of the most common causes for occurrence and development of IAs. The bone morphogenetic protein 4 (BMP4) signalling pathway is involved in regulating cell proliferation, apoptosis, and differentiation. This study aimed to investigate the effects of BMP4 on VSMCs and its underlying mechanisms. BMP4 was upregulated in the VSMCs of IAs and caused apoptosis of VSMCs through Smad1/5 phosphorylation. In addition, BMP4 overexpression significantly promoted the proliferation and migration of VSMCs and induced a phenotypic transformation from contractile to inflammatory. Our findings facilitate further understanding of the occurrence and development of IAs and provide a potential therapeutic target.

Staged stenting strategy of acutely wide-neck ruptured intracranial aneurysms: A meta-analysis and systematic review.

Objective: In the study, we explored the safety and effectiveness of staged stenting strategy for acutely wide-neck ruptured intracranial aneurysms. Methods: Online databases, including PubMed, EMBASE, the Cochrane database, and Web of Science, were retrospectively and systematically searched. The main observation indicators were the procedure-related complication rate, complete occlusion rate, and favorable clinical outcome. Meta-analysis was performed using a random or fixed effect model based on heterogeneity. Results: A total of 5 studies with 143 patients were included. The hemorrhagic complication rate of the initial coiling and staged stenting was 2.8% (4 of 143) and 0, respectively. The ischemic complication rate of the coiling and supplemental stenting was 3.5% (5 of 143) and 2.9% (4 of 139), respectively. There were no deaths due to procedure-related complications in two stages. The aneurysm complete occlusion rate was 25% (95% CI, 0.13-0.03; I2 = 4.4%; P = 0.168) after initial coiling, 54% (95% CI, 0.63-0.64; I2 = 0%; P = 0.872) after staged stenting, and 74% (95% CI, 0.66-0.81; I2 = 56.4%; P = 0.562) at follow-up, respectively. Favorable clinical outcome rate 74% (95% CI, 0.61-0.86; I2 = 50.5%; P = 0.133) after discharge of initial coiling treatment, and 86% (95% CI, 0.80-0.92; I2 = 0; P = 0.410) after discharge from stenting, and 97% (95% CI, 0.93-1.01; I2 = 43.8%; P = 0.130) at follow-up. Conclusion: Staged stenting treatment of wide-neck RIA with coiling in the acute phase followed by delayed regular stent or flow-diverter stent had high aneurysm occlusion rate, favorable clinical outcome rate and low procedure-related complication rate. A more dedicated and well-designed controlled study is warranted for further evaluation of staged stenting treatment compared to SCA in wide-neck RIA.

Microsurgical treatment of middle cerebral artery stenosis or occlusion: a single center experience and literature review.

BACKGROUND: To investigate the effect of superficial temporal artery-middle cerebral artery (STA-MCA) bypass in the treatment of MCA stenosis or occlusion. METHODS: The clinical and imaging data of 31 MCA stenosis or occlusion patients with STA-MCA bypass were analyzed retrospectively. The operation was performed by STA-MCA M4 segment bypass via the frontotemporal approach. Modified Rankin Scale (mRS) was used to evaluate the neurological function of patients. RESULTS: After operation, head computed tomography (CT) showed that there was no new infarction or hemorrhage in the operation area. CTA and CTP showed that the bypass vessel was unobstructed in 29 cases and the cerebral perfusion was improved in 31 cases. Among the 31 patients, 7 patients had postoperative complications and 13 patients had improvement of clinical symptoms. The other patients had no complications and the clinical symptoms remained unchanged. The mRs score of 31 patients after operation indicated that the neurological function was significantly improved than pre-operation. Of the 31 patients, 23 cases were followed up. The mRs score showed that the neurological function of these 23 patients was further improved than that at discharge. In addition, DSA (or CTA) and CTP showed that the bypass vessel was unobstructed and the cerebral perfusion was further improved. CONCLUSION: STA-MCA bypass was an effective method for the treatment of MCA stenosis or occlusion. However, the results should be further verified by large sample, multi-center and long-term follow-up.