Chronic Intermittent Hypoxia Regulates CaMKII-Dependent MAPK Signaling to Promote the Initiation of Abdominal Aortic Aneurysm

Obstructive sleep apnea (OSA) is highly prevalent in patients with abdominal aortic aneurysm (AAA). However, the effects of OSA on AAA initiation in a murine model of sleep apnea have not been completely studied. In this paper, Apoe-/- C57BL/6 mice infused with angiotensin II (Ang II) were placed in chronic intermittent hypoxia (CIH) condition for inducing OSA-related AAA. CIH significantly promoted the incidence of AAA and inhibited the survival of mice. By performing ultrasonography and elastic Van Gieson staining, CIH was found to be effective in promoting aortic dilation and elastin degradation. Immunohistochemical and zymography results show that CIH upregulated the expression and activity of MMP2 and MMP9 and upregulated MCP1 expression while downregulating α-SMA expression. Also, CIH exposure promoted ROS generation, apoptosis, and mitochondria damage in vascular smooth muscle cells (VSMCs), which were measured by ROS assay, TUNEL staining, and transmission electron microscopy. The result of RNA sequencing of mouse aortas displayed that 232 mRNAs were differently expressed between Ang II and Ang II+CIH groups, and CaMKII-dependent p38/Jnk was confirmed as one downstream signaling of CIH. CaMKII-IN-1, an inhibitor of CaMKII, eliminated the effects of CIH on the loss of primary VSMCs. To conclude, a mouse model of OSA-related AAA, which contains the phenotypes of both AAA and OSA, was established in this study. We suggested CIH as a risk factor of AAA initiation through CaMKII-dependent MAPK signaling.

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Transcriptional profiling and network analysis of the murine angiotensin II-induced abdominal aortic aneurysm

Physiological Genomics ◽

10.1152/physiolgenomics.00044.2011 ◽

2011 ◽

Vol 43 (17) ◽

pp. 993-1003 ◽

Cited By ~ 42

Author(s):

Joshua M. Spin ◽

Mark Hsu ◽

Junya Azuma ◽

Maureen M. Tedesco ◽

Alicia Deng ◽

...

Keyword(s):

Gene Expression ◽

Abdominal Aortic Aneurysm ◽

Angiotensin Ii ◽

Network Analysis ◽

Aortic Aneurysm ◽

Mapk Signaling ◽

Aortic Dilatation ◽

Ang Ii ◽

Abdominal Aortic ◽

Aneurysm Development

We sought to characterize temporal gene expression changes in the murine angiotensin II (ANG II)-ApoE−/− model of abdominal aortic aneurysm (AAA). Aortic ultrasound measurements were obtained over the 28-day time-course. Harvested suprarenal aortic segments were evaluated with whole genome expression profiling at 7, 14, and 28 days using the Agilent Whole Mouse Genome microarray platform and Statistical Analysis of Microarrays at a false discovery rate of <1%. A group of angiotensin-treated mice experienced contained rupture (CR) within 7 days and were analyzed separately. Progressive aortic dilatation occurred throughout the treatment period. However, the numerous early expression differences between ANG II-treated and control were not sustained over time. Ontologic analysis revealed widespread upregulation of inflammatory, immune, and matrix remodeling genes with ANG II treatment, among other pathways such as apoptosis, cell cycling, angiogenesis, and p53 signaling. CR aneurysms displayed significant decreases in TGF-β/BMP-pathway signaling, MAPK signaling, and ErbB signaling genes vs. non-CR/ANG II-treated samples. We also performed literature-based network analysis, extracting numerous highly interconnected genes associated with aneurysm development such as Spp1, Myd88, Adam17 and Lox. 1) ANG II treatment induces extensive early differential expression changes involving abundant signaling pathways in the suprarenal abdominal aorta, particularly wide-ranging increases in inflammatory genes with aneurysm development. 2) These gene expression changes appear to dissipate with time despite continued growth, suggesting that early changes in gene expression influence disease progression in this AAA model, and that the aortic tissue adapts to prolonged ANG II infusion. 3) Network analysis identified nexus genes that may constitute aneurysm biomarkers or therapeutic targets.

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Prevalence of obstructive sleep apnea in patients with abdominal aortic aneurysm

10.1183/13993003.congress-2016.pa2352 ◽

2016 ◽

Author(s):

Jacques Hernigou ◽

Bassel Dakhil ◽

Laure Belmont ◽

Jean-Claude Couffinhal ◽

Patrick Bagan

Keyword(s):

Obstructive Sleep Apnea ◽

Abdominal Aortic Aneurysm ◽

Sleep Apnea ◽

Aortic Aneurysm ◽

Abdominal Aortic ◽

Obstructive Sleep

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Relationship of obstructive sleep apnea and cardiometabolic risk factors in elderly patients with abdominal aortic aneurysm

Sleep And Breathing ◽

10.1007/s11325-014-1053-2 ◽

2014 ◽

Vol 19 (2) ◽

pp. 593-598 ◽

Cited By ~ 4

Author(s):

Vittorio E. Bianchi ◽

William G. Herbert ◽

Jonathan Myers ◽

Paul M. Ribisl ◽

Larry E. Miller ◽

...

Keyword(s):

Risk Factors ◽

Obstructive Sleep Apnea ◽

Abdominal Aortic Aneurysm ◽

Sleep Apnea ◽

Aortic Aneurysm ◽

Elderly Patients ◽

Cardiometabolic Risk ◽

Abdominal Aortic ◽

Obstructive Sleep ◽

Relationship Of

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Knockdown of long noncoding RNA GAS5 reduces vascular smooth muscle cell apoptosis by inactivating EZH2-mediated RIG-I signaling pathway in abdominal aortic aneurysm

Journal of Translational Medicine ◽

10.1186/s12967-021-03023-w ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Tianming Le ◽

Xin He ◽

Jianhua Huang ◽

Shuai Liu ◽

Yang Bai ◽

...

Keyword(s):

Smooth Muscle ◽

Abdominal Aortic Aneurysm ◽

Aortic Aneurysm ◽

Signaling Pathway ◽

Cell Apoptosis ◽

Rna Binding ◽

Ectopic Expression ◽

Tunel Staining ◽

Ang Ii ◽

Abdominal Aortic

Abstract Background Abdominal aortic aneurysm (AAA), an irreversible cardiovascular disease prevalent in the artery, causes the increase of the aneurysm diameter over time, and is a fatal phenomenon inducing sidewall rupture. Long noncoding RNAs (lncRNAs) serve as promising biomarkers for AAA. In the present study, we sought to define the role of lncRNA growth-arrest-specific transcript 5 (GAS5) in growth of smooth muscle cells (SMC) and progression of AAA. Methods Initially, we established angiotensin II (Ang II)-induced AAA mouse models and Ang II-treated vascular SMC model. RT-qPCR and Western blot analysis were adopted to determine expression of GAS5 and zeste homolog 2 (EZH2). After ectopic expression and depletion experiments in Ang II-treated mice and vascular SMCs, cell apoptosis was detected in SMCs using flow cytometry and in mice using TUNEL staining. The binding of GAS5 and EZH2 was evaluated using RNA binding protein immunoprecipitation (RIP) and Co-IP assays. Results Increased GAS5 and RIG-I but decreased EZH2 were found in aortic tissues of AAA mice. EZH2 overexpression inhibited AAA formation and suppressed SMC apoptosis. Functionally, EZH2 blocked the RIG-I signaling pathway and consequently inhibited SMC apoptosis. GAS5 regulated EZH2 transcription in a negative manner in SMCs. Knockdown of GAS5 attenuated SMC apoptosis, which was reversed by EZH2 inhibition or RIG-I overexpression. Conclusions The current study demonstrated that GAS5 induced SMC apoptosis and subsequent AAA onset by activating EZH2-mediated RIG-I signaling pathway, highlighting GAS5 as a novel biomarker for AAA.

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Novel proteins associated with chronic intermittent hypoxia and obstructive sleep apnea: From rat model to clinical evidence

PLoS ONE ◽

10.1371/journal.pone.0253943 ◽

2021 ◽

Vol 16 (6) ◽

pp. e0253943

Author(s):

Xiaojun Tang ◽

Shisheng Li ◽

Xinming Yang ◽

Qinglai Tang ◽

Ying Zhang ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Rat Model ◽

Intermittent Hypoxia ◽

Mapk Signaling ◽

Enzyme Linked Immunosorbent Assay ◽

Chronic Intermittent Hypoxia ◽

Control Group ◽

Obstructive Sleep ◽

And Control

Objective To screen for obstructive sleep apnea (OSA) biomarkers, isobaric tags for relative and absolute quantitation (iTRAQ)-labeled quantitative proteomics assay was used to identify differentially expressed proteins (DEPs) during chronic intermittent hypoxia (CIH). Method The iTRAQ technique was applied to compare DEPs in the serum of a CIH rat model and control group. Biological analysis of DEPs was performed using Gene Ontology and Kyoto Encyclopedia to explore related biological functions and signaling pathways. Enzyme-linked immunosorbent assay (ELISA) was performed to validate their expression in sera from patients with OSA and CIH rats. Results Twenty-three DEPs (fold change ≥1.2 or ≤0.833, p<0.05) were identified, and two DEPs (unique peptides>3 and higher coverage) were further verified by ELISA in the CIH rat model and OSA subject: apolipoprotein A-IV (APOA4, p<0.05) and Tubulin alpha-1A chain (TUBA1A, p<0.05). Both groups showed significant differences in the expression levels of DEPs between the CIH and control groups and the severe OSA and non-OSA groups. APOA4 was found to be upregulated and TUBA1A downregulated in both the sera from OSA patients and CIH rats, on comparing proteomics results with clinical results. There were two pathways that involved three DEPs, the mitogen-activated protein kinase (MAPK) signaling pathway (p<0.05) and cytokine-cytokine receptor interaction (p<0.05). Conclusion APOA4 and TUBA1A may be potential novel biomarkers for CIH and OSA, and may play an important role in the development of OSA complications.

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Inhibition of Peptidyl Arginine Deiminase 4-Dependent Neutrophil Extracellular Trap Formation Reduces Angiotensin II-Induced Abdominal Aortic Aneurysm Rupture in Mice

Frontiers in Cardiovascular Medicine ◽

10.3389/fcvm.2021.676612 ◽

2021 ◽

Vol 8 ◽

Author(s):

Ming Wei ◽

Xia Wang ◽

Yanting Song ◽

Di Zhu ◽

Dan Qi ◽

...

Keyword(s):

Abdominal Aortic Aneurysm ◽

Angiotensin Ii ◽

Aortic Aneurysm ◽

Tissue Injury ◽

Arginine Deiminase ◽

Tunel Staining ◽

Ang Ii ◽

Elastin Degradation ◽

Abdominal Aortic

Objective: Neutrophil infiltration plays an important role in the initiation and development of abdominal aortic aneurysm (AAA). Recent studies suggested that neutrophils could release neutrophil extracellular traps (NETs), leading to tissue injury in cardiovascular diseases. However, the role of NETs in AAA is elusive. This study aimed to investigate the role and underlying mechanism of NETs in AAA development.Methods and Results: An angiotensin II (Ang II) infusion-induced AAA model was established to investigate the role of NETs during AAA development. Immunofluorescence staining showed that citrullinated histone 3 (citH3), myeloperoxidase (MPO), and neutrophil elastase (NE) (NET marker) expressions were significantly increased in Ang II-infused ApoE−/− mice. The circulating double-stranded DNA (dsDNA) level was also elevated, indicating the increased NET formation during AAA. PAD4 inhibitor YW3-56 inhibited Ang II-induced NET formation. Disruption of NET formation by YW3-56 markedly reduced Ang II-induced AAA rupture, as revealed by decreased aortic diameter, vascular smooth muscle cell (VSMC) apoptosis, and elastin degradation. Apoptosis of VSMC was evaluated by TUNEL staining and Annexin V-FITC/PI staining through flow cytometry. Western blot and inhibition experiments revealed that NETs induced VSMC apoptosis via p38/JNK pathway, indicating that PAD4-dependent NET formation played an important role in AAA.Conclusions: This study suggests that PAD4-dependent NET formation is critical for AAA rupture, which provides a novel potential therapeutic strategy for AAA disease.

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