SP1-mediated transcriptional activation of PTTG1 regulates the migration and phenotypic switching of aortic vascular smooth muscle cells in aortic dissection through MAPK signaling

Downregulation of LILRB4 Promotes Human Aortic Smooth Muscle Cell Contractile Phenotypic Switch and Apoptosis in Aortic Dissection

Aortic dissection (AD) is a severe vascular disease with high rates of mortality and morbidity. However, the underlying molecular mechanisms of AD remain unclear. Differentially expressed genes (DEGs) were screened by bioinformatics methods. Alterations of histopathology and inflammatory factor levels in β-aminopropionitrile (BAPN)-induced AD mouse model were evaluated through Hematoxylin-Eosin (HE) staining and Enzyme-linked immunosorbent assay (ELISA), respectively. Reverse transcription quantitative real-time polymerase chain reaction was performed to detect DEGs expression. Furthermore, the role of LILRB4 in AD was investigated through Cell Counting Kit-8 (CCK-8), wound healing, and flow cytometry. Western blotting was employed to assess the phenotypic switch and extracellular matrix (ECM)-associated protein expressions in platelet-derived growth factor-BB (PDGF-BB)-stimulated in vitro model of AD. In the AD mouse model, distinct dissection formation was observed. TNF-α, IL-1β, IL-8, and IL-6 levels were higher in the AD mouse model than in the controls. Six hub genes were identified, including LILRB4, TIMP1, CCR5, CCL7, MSR1, and CLEC4D, all of which were highly expressed. Further exploration revealed that LILRB4 knockdown inhibited the cell vitality and migration of PDGF-BB-induced HASMCs while promoting apoptosis and G0/G1 phase ratio. More importantly, LILRB4 knockdown promoted the protein expression of α-SMA and SM22α, while decreasing the expression of Co1, MMP2, and CTGF, which suggested that LILRB4 silencing promoted contractile phenotypic transition and ECM stability. LILRB4 knockdown inhibits the progression of AD. Our study provides a new potential target for the clinical treatment of AD.

Identification of immune-related molecular markers in intracranial aneurysm (IA) based on machine learning and cytoscape-cytohubba plug-in

BACKGROUND

Intracranial aneurysm (IA) is a common cerebrovascular disease. The immune mechanism of IA is more complicated, and it is unclear so far. Therefore, it is necessary to continue to explore the immune related molecular mechanism of IA.

METHODS

All data were downloaded from the public database. Limma package and ssGSEA algorithm was used to identify differentially expressed mRNAs (DEmRNAs) and analyze immune cell infiltration, respectively. Machine learning and cytoscape-cytohubba plug-in was used to identify key immune types and multicentric DEmRNAs of IA, respectively. Multicentric DEmRNAs related to key immune cells were screened out as key DEmRNAs by Spearman correlation analysis. Diagnostic models, competing endogenous RNA (ceRNA) regulatory network and transcription factor regulatory network were constructed based on key DEmRNAs. Meanwhile, drugs related to key DEmRNAs were screened out based on DGIdb database. The expression of key DEmRNAs was also verified by real time-PCR.

RESULTS

In this study, 7 key DEmRNAs (NRXN1, GRIA2, SLC1A2, SLC17A7, IL6, VEGFA and SYP) associated with key differential immune cell infiltration (CD56bright natural killer cell, Immature B cell and Type 1 T helper cell) were identified. Functional enrichment analysis showed that VEGFA and IL6 may be involved in the regulation of the PI3K-Akt signaling pathway. Moreover, IL6 was also found to be enriched in cytokine-cytokine receptor interaction signaling pathway. In the ceRNA regulatory network, a large number of miRNAs and lncRNAs were found. In the transcription factor regulatory network, the transcription factor SP1 was correlated with VEGFA, SYP and IL6. It is also predicted that drugs related to key DEmRNAs such as CARBOPLATIN, FENTANYL and CILOSTAZOL may contribute to the treatment of IA. In addition, it was also found that SVM and RF models based on key DEmRNAs may be potential markers for diagnosing IA and unruptured intracranial aneurysm (UIA), respectively. The expression trend of key DEmRNAs verified by real-time PCR was consistent with the bioinformatics analysis results.

CONCLUSION

The identification of molecules and pathways in this study provides a theoretical basis for understanding the immune related molecular mechanism of IA. Meanwhile, the drug prediction and diagnosis model construction may also be helpful for clinical diagnosis and management.

Comprehensive Analysis of Endoplasmic Reticulum Stress in Intracranial Aneurysm

Background

Aberrant endoplasmic reticulum stress (ERS) plays an important role in multiple cardiovascular diseases. However, their implication in intracranial aneurysms (IAs) remains unclear. We designed this study to explore the general expression pattern and potential functions of ERS in IAs.

Methods

Five Gene Expression Omnibus (GEO) microarray datasets were used as the training cohorts, and 3 GEO RNA sequencing (RNA-seq) datasets were used as the validating cohorts. Differentially expressed genes (DEGs), functional enrichment, Lasso regression, logistic regression, ROC analysis, immune cell profiling, vascular smooth muscle cell (VSMC) phenotyping, weighted gene coexpression network analysis (WGCNA), and protein-protein interaction (PPI) analysis were applied to investigate the role of ERS in IA. Finally, we predicted the upstream transcription factor (TF)/miRNA and potential drugs targeting ERS.

Results

Significant DEGs were majorly associated with ERS, autophagy, and metabolism. Eight-gene ERS signature and IRE1 pathway were identified during the IA formation. WGCNA showed that ERS was highly associated with a VSMC synthesis phenotype. Next, ERS-VSMC-metabolism-autophagy PPI and ERS-TF-miRNA networks were constructed. Finally, we predicted 9 potential drugs targeting ERS in IAs.

Conclusion

ERS is involved in IA formation. Upstream and downstream regulatory networks for ERS were identified in IAs. Novel potential drugs targeting ERS were also proposed, which may delay IA formation and progress.

LDHA mediated degradation of extracellular matrix is a potential target for the treatment of aortic dissection

Aortic dissection (AD) is a disease with high mortality and lacks effective drug treatment. Recent studies have shown that the development of AD is closely related to glucose metabolism. Lactate dehydrogenase A (LDHA) is a key glycolytic enzyme and plays an important role in cardiovascular disease. However, the role of LDHA in the progression of AD remains to be elucidated. Here, we found that the level of LDHA was significantly elevated in AD patients and the mouse model established by BAPN combined with Ang II. In vitro, the knockdown of LDHA reduced the growth of human aortic vascular smooth muscle cells (HAVSMCs), glucose consumption, and lactate production induced by PDGF-BB. The overexpression of LDHA in HAVSMCs promoted the transformation of HAVSMCs from contractile phenotype to synthetic phenotype, and increased the expression of MMP2/9. Mechanistically, LDHA promoted MMP2/9 expression through the LDHA-NDRG3-ERK1/2-MMP2/9 pathway. In vivo, Oxamate, LDH and lactate inhibitor, reduced the degradation of elastic fibers and collagen deposition, inhibited the phenotypic transformation of HAVSMCs from contractile phenotype to synthetic phenotype, reduced the expression of NDRG3, p-ERK1/2, and MMP2/9, and delayed the progression of AD. To sum up, the increase of LDHA promotes the production of MMP2/9, stimulates the degradation of extracellular matrix (ECM), and promoted the transformation of HAVSMCs from contractile phenotype to synthetic phenotype. Oxamate reduced the progression of AD in mice. LDHA may be a therapeutic target for AD.