MiR-144-5p limits experimental abdominal aortic aneurysm formation by mitigating M1 macrophage-associated inflammation: Suppression of TLR2 and OLR1

Aortic aneurysm: pathophysiology and therapeutic options

Aortic aneurysm (AA) is an aortic disease with a high mortality rate, and other than surgery no effective preventive or therapeutic treatment have been developed. The renin-angiotensin system (RAS) is an important endocrine system that regulates vascular health. The ACE2/Ang-(1-7)/MasR axis can antagonize the adverse effects of the activation of the ACE/Ang II/AT1R axis on vascular dysfunction, atherosclerosis, and the development of aneurysms, thus providing an important therapeutic target for the prevention and treatment of AA. However, products targeting the Ang-(1-7)/MasR pathway still lack clinical validation. This review will outline the epidemiology of AA, including thoracic, abdominal, and thoracoabdominal AA, as well as current diagnostic and treatment strategies. Due to the highest incidence and most extensive research on abdominal AA (AAA), we will focus on AAA to explain the role of the RAS in its development, the protective function of Ang-(1-7)/MasR, and the mechanisms involved. We will also describe the roles of agonists and antagonists, suggest improvements in engineering and drug delivery, and provide evidence for Ang-(1-7)/MasR's clinical potential, discussing risks and solutions for clinical use. This study will enhance our understanding of AA and offer new possibilities and promising targets for therapeutic intervention.

Roles and Mechanisms of miRNAs in Abdominal Aortic Aneurysm: Signaling Pathways and Clinical Insights

PURPOSE OF REVIEW

Abdominal aortic aneurysm refers to a serious medical condition that can cause the irreversible expansion of the abdominal aorta, which can lead to ruptures that are associated with up to 80% mortality. Currently, surgical and interventional procedures are the only treatment options available for treating abdominal aortic aneurysm patients. In this review, we focus on the upstream and downstream molecules of the microRNA-related signaling pathways and discuss the roles, mechanisms, and targets of microRNAs in abdominal aortic aneurysm modulation to provide novel insights for precise and targeted drug therapy for the vast number of abdominal aortic aneurysm patients.

RECENT FINDINGS

Recent studies have highlighted that microRNAs, which are emerging as novel regulators of gene expression, are involved in the biological activities of regulating abdominal aortic aneurysms. Accumulating studies suggested that microRNAs modulate abdominal aortic aneurysm development through various signaling pathways that are yet to be comprehensively summarized. A total of six signaling pathways (NF-κB signaling pathway, PI3K/AKT signaling pathway, MAPK signaling pathway, TGF-β signaling pathway, Wnt signaling pathway, and P53/P21 signaling pathway), and a total of 19 miRNAs are intimately associated with the biological properties of abdominal aortic aneurysm through targeting various essential molecules. MicroRNAs modulate the formation, progression, and rupture of abdominal aortic aneurysm by regulating smooth muscle cell proliferation and phenotype change, vascular inflammation and endothelium function, and extracellular matrix remodeling. Because of the broad crosstalk among signaling pathways, a comprehensive analysis of miRNA-mediated signaling pathways is necessary to construct a well-rounded upstream and downstream regulatory network for future basic and clinical research of AAA therapy.

Epigenetic modifications in abdominal aortic aneurysms: from basic to clinical

Abdominal Aortic Aneurysm (AAA) is a disease characterized by localized dilation of the abdominal aorta, involving multiple factors in its occurrence and development, ultimately leading to vessel rupture and severe bleeding. AAA has a high mortality rate, and there is a lack of targeted therapeutic drugs. Epigenetic regulation plays a crucial role in AAA, and the treatment of AAA in the epigenetic field may involve a series of related genes and pathways. Abnormal expression of these genes may be a key factor in the occurrence of the disease and could potentially serve as promising therapeutic targets. Understanding the epigenetic regulation of AAA is of significant importance in revealing the mechanisms underlying the disease and identifying new therapeutic targets. This knowledge can contribute to offering AAA patients better clinical treatment options beyond surgery. This review systematically explores various aspects of epigenetic regulation in AAA, including DNA methylation, histone modification, non-coding RNA, and RNA modification. The analysis of the roles of these regulatory mechanisms, along with the identification of relevant genes and pathways associated with AAA, is discussed comprehensively. Additionally, a comprehensive discussion is provided on existing treatment strategies and prospects for epigenetics-based treatments, offering insights for future clinical interventions.

The potential role of miRNA in regulating macrophage polarization

Macrophage polarization is a dynamic process determining the outcome of various physiological and pathological situations through inducing pro-inflammatory responses or resolving inflammation via exerting anti-inflammatory effects. The miRNAs are epigenetic regulators of different biologic pathways that target transcription factors and signaling molecules to promote macrophage phenotype transition and regulate immune responses. Modulating the macrophage activation, differentiation, and polarization by miRNAs is crucial for immune responses in response to microenvironmental signals and under various physiological and pathological conditions. In term of clinical significance, regulating macrophage polarization via miRNAs could be utilized for inflammation control. Also, understanding the role of miRNAs in macrophage polarization can provide insights into diagnostic strategies associated with dysregulated miRNAs and for developing macrophage-centered therapeutic methods. In this case, targeting miRNAs to further regulate of macrophage polarization may become an efficient strategy for treating immune-associated disorders. The current review investigated and categorized various miRNAs directly or indirectly involved in macrophage polarization by targeting different transcription factors and signaling pathways. In addition, prospects for regulating macrophage polarization via miRNA as a therapeutic choice that could be implicated in various pathological conditions, including cancer or inflammation-mediated injuries, were discussed.

Clinical and preclinical evaluation of miR-144-5p as a key target for major depressive disorder

BACKGROUND

Neuronal abnormalities are closely associated with major depressive disorder (MDD). Available evidence suggests a role for microRNAs (miRNAs) in regulating the expression of genes involved in MDD. Hence, miRNAs that can be potential therapeutic targets need to be identified.

METHODS

A mouse model of chronic unpredictable stress (CUS) was used to evaluate the function of miRNAs in MDD. miR-144-5p was screened from the hippocampi of CUS mice based on sequencing results. Adenovirus-associated vectors were used to overexpress or knockdown miR-144-5p in mice. BpV(pic) and LY294002 were used to determine the relationship between miR-144-5p target genes PTEN and TLR4 in neuronal impairment caused by miR-144-5p deficiency. Western blotting, immunofluorescence, ELISA immunosorbent assay, and Golgi staining were used to detect neuronal abnormalities. Serum samples from healthy individuals and patients with MDD were used to detect miR-144-5p levels in the serum and serum exosomes using qRT-PCR.

RESULTS

miR-144-5p expression was significantly decreased within the hippocampal dentate gyrus (DG) of CUS mice. Upregulation of miR-144-5p in the DG ameliorated depression-like behavior in CUS mice and attenuated neuronal abnormalities by directly targeting PTEN and TLR4 expression. Furthermore, miR-144-5p knockdown in normal mice led to depression-like behavior via inducing neuronal abnormalities, including abnormal neurogenesis, neuronal apoptosis, altered synaptic plasticity, and neuroinflammation. miR-144-5p deficiency-mediated neuronal impairment was mediated by PI3K/Akt/FoxO1 signaling. Furthermore, miR-144-5p levels were downregulated in the sera of patients with MDD and associated with depressive symptoms. Consistently, serum exosome-derived miR-144-5p levels were decreased in patients with MDD.

CONCLUSION

miR-144-5p plays a vital role in regulating neuronal abnormalities in depression. Our findings provide translational evidence that miR-144-5p is a new potential therapeutic target for MDD.

miR34a-5p impedes CLOCK expression in chronodisruptive C57BL/6J mice and potentiates pro-atherogenic manifestations

INTRODUCTION

Altered circadian rhythms underlie manifestation of several cardiovascular disorders, however a little is known about the mediating biomolecules. Multiple transcriptional-translational feedback loops control circadian-clockwork wherein; micro RNAs (miRNAs) are known to manifest post transcriptional regulation. This study assesses miR34a-5p as a mediating biomolecule.

METHOD

8-10-week-old male C57BL/6J mice (n = 6/group) were subjected to photoperiodic manipulation induced chronodisruption and thoracic aortae were examined for miRNA, gene (qPCR) and protein (Immunoblot) expression studies. Histomorphological changes were assessed for pro-atherogenic manifestations (fibrillar arrangement, collagen/elastin ratio, intima-media thickening). Computational studies for miRNA-mRNA target prediction were done using TargetScan and miRDB. Correlative in vitro studies were done in serum synchronized HUVEC cells. Time point based studies were done at five time points (ZT 0, 6, 12, 18, 24) in 24h.

RESULTS

Chronodisruption induced hypomethylation in the promoter region of miR34a-5p, in the thoracic aortae, culminating in elevated miRNA titers. In a software-based detection of circadian-clock-associated targets of miR34a-5p, Clock and Sirt1 genes were identified. Moreover, miR34a-5p exhibited antagonist circadian oscillations to that of its target genes CLOCK and SIRT1 in endothelial cells. Luciferase reporter gene assay further showed that miR34a-5p interacts with the 3'UTR of the Clock gene to lower its expression, disturbing the operation of positive arm of circadian clock system. Elevated miR34a-5p and impeded SIRT1 expression in a chronodisruptive aortae exhibited pro-atherogenic changes observed in form of gene expression, increased collagen/elastin ratio, fibrillar derangement and intimal-media thickening.

CONCLUSION

The study reports for the first time chronodisruption mediated miR34a-5p elevation, its circadian expression and interaction with the 3'UTR of Clock gene to impede its expression. Moreover, elevated miR34a-5p and lowered SIRT1 expression in the chronodisruptive aortae lead off cause-consequence relationship of chronodisruption mediated proatherogenic changes.

Role of macrophages in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a severe cardiopulmonary vascular disease characterized by progressive pulmonary artery pressure elevation, increased pulmonary vascular resistance and ultimately right heart failure. Studies have demonstrated the involvement of multiple immune cells in the development of PAH in patients with PAH and in experimental PAH. Among them, macrophages, as the predominant inflammatory cells infiltrating around PAH lesions, play a crucial role in exacerbating pulmonary vascular remodeling in PAH. Macrophages are generally polarized into (classic) M1 and (alternative) M2 phenotypes, they accelerate the process of PAH by secreting various chemokines and growth factors (CX3CR1, PDGF). In this review we summarize the mechanisms of immune cell action in PAH, as well as the key factors that regulate the polarization of macrophages in different directions and their functional changes after polarization. We also summarize the effects of different microenvironments on macrophages in PAH. The insight into the interactions between macrophages and other cells, chemokines and growth factors may provide important clues for the development of new, safe and effective immune-targeted therapies for PAH.

Association of miR-144 levels in the peripheral blood with COVID-19 severity and mortality

Coronavirus disease-2019 (COVID-19) can be asymptomatic or lead to a wide symptom spectrum, including multi-organ damage and death. Here, we explored the potential of microRNAs in delineating patient condition and predicting clinical outcome. Plasma microRNA profiling of hospitalized COVID-19 patients showed that miR-144-3p was dynamically regulated in response to COVID-19. Thus, we further investigated the biomarker potential of miR-144-3p measured at admission in 179 COVID-19 patients and 29 healthy controls recruited in three centers. In hospitalized patients, circulating miR-144-3p levels discriminated between non-critical and critical illness (AUC_miR-144-3p = 0.71; p = 0.0006), acting also as mortality predictor (AUC_miR-144-3p = 0.67; p = 0.004). In non-hospitalized patients, plasma miR-144-3p levels discriminated mild from moderate disease (AUC_miR-144-3p = 0.67; p = 0.03). Uncontrolled release of pro-inflammatory cytokines can lead to clinical deterioration. Thus, we explored the added value of a miR-144/cytokine combined analysis in the assessment of hospitalized COVID-19 patients. A miR-144-3p/Epidermal Growth Factor (EGF) combined score discriminated between non-critical and critical hospitalized patients (AUC_{miR-144-3p/EGF} = 0.81; p < 0.0001); moreover, a miR-144-3p/Interleukin-10 (IL-10) score discriminated survivors from nonsurvivors (AUC_{miR-144-3p/IL-10} = 0.83; p < 0.0001). In conclusion, circulating miR-144-3p, possibly in combination with IL-10 or EGF, emerges as a noninvasive tool for early risk-based stratification and mortality prediction in COVID-19.

Construction and analysis of competing endogenous RNA network and patterns of immune infiltration in abdominal aortic aneurysm

Background

Various studies have highlighted the role of circular RNAs (circRNAs) as critical molecular regulators in cardiovascular diseases, but its role in abdominal aortic aneurysm (AAA) is unclear. This study explores the potential molecular mechanisms of AAA based on the circRNA-microRNA (miRNA)-mRNA competing endogenous RNA (ceRNA) network and immune cell infiltration patterns.

Methods

The expression profiles of circRNAs (GSE144431) and mRNAs (GSE57691 and GSE47472) were obtained from the Gene Expression Omnibus (GEO). Then, the differentially expressed circRNAs (DEcircRNAs) and mRNAs (DEmRNAs) between AAA patients and healthy control samples, and the target miRNAs of these DEmRNAs and DEcircRNAs were identified. Based on the miRNA-DEmRNAs and miRNA-DEcircRNAs pairs, the ceRNA network was constructed. Furthermore, the proportion of the 22 immune cell types in AAA patients was assessed using cell type identification by estimating relative subsets of RNA transcripts (CIBERSORT) algorithm. The expressions of key genes and immune cell infiltration were validated using clinical specimens.

Results

A total of 214 DEmRNAs were identified in the GSE57691 and GSE47472 datasets, and 517 DEcircRNAs were identified in the GSE144431 dataset. The ceRNA network included 19 circRNAs, 36 mRNAs, and 68 miRNAs. Two key genes, PPARG and FOXO1, were identified among the hub genes of the established protein-protein interaction between mRNAs in the ceRNA network. Moreover, seven types of immune cells were differentially expressed between AAA patients and healthy control samples. Hub genes in ceRNA, such as FOXO1, HSPA8, and RAB5C, positively correlated with resting CD4 memory T cells or M1 macrophages, or both.

Conclusion

In conclusion, a ceRNA interaction axis was constructed. The composition of infiltrating immune cells was analyzed in the abdominal aorta of AAA patients and healthy control samples. This may help identify potential therapeutic targets for AAA.

LncRNA OIP5-AS1 reduces renal epithelial cell apoptosis in cisplatin-induced AKI by regulating the miR-144-5p/PKM2 axis

BACKGROUND

The abnormal expression of long non-coding RNA (lncRNA) Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1) has been observed in many human cancers and the underlying mechanisms have been well studied. However, the function of OIP5-AS1 in acute kidney injury (AKI) remains unclear.

METHODS

To explore the role of OIP5-AS1 in the progression of AKI, the cisplatin-induced AKI mouse and cell model were established. To confirm the potential protective effect of OIP5-AS1 during cisplatin-induced AKI, rescue experiments were performed. Targetscan was used to predict the potential targets of miR-144-5p. To further determine whether the effect of miR-144-5p during cisplatin-induced AKI was mediated by PMK2, the recuse experiments using PMK2 overexpressing vector was applied.

RESULTS

OIP5-AS1 was significantly downregulated both in cisplatin-induced AKI mice and human renal tubular cell line HK-2 cells. Moreover, overexpression of OIP5-AS1 efficiently promoted cell growth and reduced cisplatin-induced apoptosis of HK-2 cells. Furthermore, OIP5-AS1 was identified as a sponge of miR-144-5p, and upregulation of miR-144-5p could significantly reverse overexpression of OIP5-AS1-induced protective effect on the damage of cisplatin to HK-2 cells. In addition, pyruvate kinase M2 (PKM2) was found to be a direct target of miR-144-5p, and overexpression of PKM2 efficiently reversed the effect of miR-144-5p mimics on the damage in cisplatin-stimulated HK-2 cells.

CONCLUSIONS

OIP5-AS1 reduced the apoptosis of cisplatin-stimulated renal epithelial cells by targeting the miR-144-5p/PKM2 axis, which extended the regulatory network of lncRNAs in cisplatin-induced AKI and also provided a novel therapeutic target for AKI treatment.

MicroRNA sequencing in patients with coronary artery disease – considerations for use as biomarker for thrombotic risk

MicroRNAs (miRNAs) are small RNAs integral in the regulation of gene expression. Analysis of circulating miRNA levels may identify patients with coronary artery disease (CAD) at risk for recurrent myocardial infarction (MI) after percutaneous coronary interventions (PCIs). Subjects with CAD were selected from the GENCATH cardiac catheterization biobank. Subjects with recurrent MI after PCI were compared with those without recurrent MI during follow‐up in the initial (n = 48) and replication cohort (n = 67). Next generation MiRNA sequencing was performed on plasma samples and whole blood samples fixed with PAXGENE tubes upon collection. Overall, 164 miRNAs derived from whole blood were differentially expressed in the replication cohort between subjects with and without recurrent MI events (p < 0.05), with 69 remaining significant after false‐discovery rate (FDR) correction. None of the miRNAs in plasma was significantly different by FDR among subjects with and without MI. Overall, correlation between direction of effects between plasma and whole blood assays was variable, and only two miRNAs were concordant and significant in both. Associations of miRNA with vascular disease, MI, and thrombosis were further explored. MiRNA profiling has potential as the future biomarker for disease prognosis and treatment response marker in secondary treatment of patients with CAD after PCI. Whole blood may be the preferred sample source as compared to plasma.

Nuclear Paraspeckle Assembly Transcript 1 Enhances Hydrogen Peroxide-Induced Human Vascular Smooth Muscle Cell Injury by Regulating miR-30d-5p/A Disintegrin and Metalloprotease 10

BACKGROUND

Nuclear paraspeckle assembly transcript 1 (NEAT1) has been reported to be involved in the progression of many cancers; however, the role and mechanisms underlying NEAT1 in abdominal aortic aneurysm (AAA) remain unclear.

METHODS AND RESULTS

The expression of NEAT1, miR-30d-5p and A disintegrin and metalloprotease 10 (ADAM10) was measured by qRT-PCR and western blot. Functional experiments were conducted by using a CCK-8 assay, EDU assay, flow cytometry, western blot, ELISA, and commercial kits. The target relation was confirmed by dual-luciferase reporter assay and the RIP assay. It was then found that NEAT1 was upregulated in peripheral blood of AAA patients ~3.46-fold, smooth muscle cells (SMCs) isolated from AAA tissues ~2.6-fold and in a hydrogen peroxide (H2O2)-induced injury model of human vascular SMC (HVSMCs) ~2.0- and 3.9-fold at 50 µmol/L and 200 µmol/L H2O2treatment, respectively. NEAT1 deletion attenuated H2O2-induced cell proliferation promotion (40.0% vs. 74.3%), apoptosis inhibition (25.0% vs. 13.5%), and reduction of inflammatory response and oxidative stress in HVSMCs. Mechanistically, NEAT1 targeted miR-30d-5p to prevent the degradation of its target, ADAM10, in HVSMCs. Further rescue experiments suggested miR-30d-5p inhibition mitigated the effects of NEAT1 deletion on H2O2-induced HVSMCs. Moreover, ADAM10 overexpression counteracted the inhibitory functions of miR-30d-5p on H2O2-evoked HVSMC injury.

CONCLUSIONS

NEAT1 promoted H2O2-induced HVSMC injury by inducing cell apoptosis, inflammation and oxidative stress through miR-30d-5p/ADAM10 axis, indicating the possible involvement of NEAT1 in the pathogenesis of AAA.

Circular RNA Cdyl promotes abdominal aortic aneurysm formation by inducing M1 macrophage polarization and M1-type inflammation

Macrophage polarization plays a crucial role in regulating abdominal aortic aneurysm (AAA) formation. Circular RNAs (circRNAs) are important regulators of macrophage polarization during the development of cardiovascular diseases. How-ever, the roles of circRNAs in regulating AAA formation through modulation of macrophage polarization remain unknown. In the present study, we compared circRNA microarray data under two distinct polarizing conditions (M1 and M2 macrophages) and identified an M1-enriched circRNA, circCdyl. Loss- and gain-of-function assay results demonstrated that circCdyl overexpression accelerated angiotensin II (Ang II)- and calcium chloride (CaCl₂)-induced AAA formation by promoting M1 polarization and M1-type inflammation, while circCdyl deficiency showed the opposite effects. RNA pulldown, mass spectrometry analysis, and RNA immunoprecipitation (RIP) assays were conducted to elucidate the underlying mechanisms by which circCdyl regulates AAA formation and showed that circCdyl promotes vascular inflammation and M1 polarization by inhibiting interferon regulatory factor 4 (IRF4) entry into the nucleus, significantly inducing AAA formation. In addition, circCdyl was shown to act as a let-7c sponge, promoting C/EBP-δ expression in macrophages to induce M1 polarization. Our results indicate an important role for circCdyl-mediated macrophage polarization in AAA formation and provide a potent therapeutic target for AAA treatment.

Integrated analysis and the identification of a circRNA-miRNA-mRNA network in the progression of abdominal aortic aneurysm

Background

Abdominal aortic aneurysm (AAA) is a disease commonly seen in the elderly. The aneurysm diameter increases yearly, and the larger the AAA the higher the risk of rupture, increasing the risk of death. However, there are no current effective interventions in the early stages of AAA.

Methods

Four gene expression profiling datasets, including 23 normal artery (NOR) tissue samples and 97 AAA tissue samples, were integrated in order to explore potential molecular biological targets for early intervention. After preprocessing, differentially expressed genes (DEGs) between AAA and NOR were identified using LIMMA package. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis were conducted using the DAVID database. The protein-protein interaction network was constructed and hub genes were identified using the STRING database and plugins in Cytoscape. A circular RNA (circRNA) profile of four NOR tissues versus four AAA tissues was then reanalyzed. A circRNA-miRNA-mRNA interaction network was constructed after predictions were made using the Targetscan and Circinteractome databases.

Results

A total of 440 DEGs (263 up-regulated and 177 down-regulated) were identified in the AAA group, compared with the NOR group. The majority were associated with the extracellular matrix, tumor necrosis factor-α, and transforming growth factor-β. Ten hub gene-encoded proteins (namely IL6, RPS27A, JUN, UBC, UBA52, FOS, IL1B, MMP9, SPP1 and CCL2) coupled with a higher degree of connectivity hub were identified after protein‐protein interaction network analysis. Our results, in combination with the results of previous studies revealed that miR-635, miR-527, miR-520h, miR-938 and miR-518a-5p may be affected by circ_0005073 and impact the expression of hub genes such as CCL2, SPP1 and UBA52. The miR-1206 may also be affected by circ_0090069 and impact RPS27A expression.

Conclusions

This circRNA-miRNA-mRNA network may perform critical roles in AAA and may be a novel target for early intervention.

Long non-coding RNA PVT1/microRNA miR-3127-5p/NCK-associated protein 1-like axis participates in the pathogenesis of abdominal aortic aneurysm by regulating vascular smooth muscle cells

The long non-coding RNA plasmacytoma variant translocation 1 (lncRNA PVT1) has been implicated in the progression of abdominal aortic aneurysms (AAA). However, the detailed mechanism requires further analysis. Our study was aimed at interrogating the mechanism of PVT1 in an H₂O₂-induced AAA model in vitro. The expression of lncRNA PVT1, microRNA miR-3127-5p, and NCK-associated protein 1-like (NCKAP1L) was examined in AAA tissues and H₂O₂-treated vascular smooth muscle cells (VSMCs). Cell proliferation was assayed using Cell Counting Kit-8 (CCK8) and 5-Bromodeoxyuridine (BrdU) assays. Meanwhile, 5-Ethynyl-2'-deoxyuridine (EdU) staining was performed to assess cell apoptosis and caspase-3 activity. IL-1β and caspase-1 expression was also assessed using Western blotting to determine inflammasome activation in H₂O₂-treated VSMCs. Luciferase reporter assays addressed the possible interaction between miR-3127-5p and PVT1 or NCKAP1L, which was predicted by starBase analysis. PVT1 and NCKAP1L expression was elevated in AAA tissues and induced the AAA model in vitro, whereas miR-3127-5p showed the opposite trend. Functionally, PVT1 silencing promoted cell proliferation and reduced the apoptotic rate and inflammasome activation in H₂O₂-treated VSMCs. Mechanical investigation demonstrated that PVT1 acted as a sponge of miR-3127-5p to modulate NCKAP1L expression, resulting in suppression of VSMC proliferation, induction of apoptosis, and activation of inflammation. In conclusion, PVT1 participates in AAA progression through the miR-3127-5p/NCKAP1L axis and may be a promising biosignature and therapeutic target for AAA.

Mesenchymal stem cells-derived exosomes modulate vascular endothelial injury via miR-144-5p/PTEN in intracranial aneurysm

Phosphatase and tensin homolog (PTEN) is known to be involved in the pathogenesis of intracranial aneurysm (IA). This study investigated the molecular mechanism of exosomal miR-144-5p (ex-miR-144-5p) and PTEN in IA. Ex-miR-144-5p expression was assessed in serum from individuals with ruptured intracranial aneurysm (RA) or unruptured intracranial aneurysm (UA), and healthy controls (HC). Vascular endothelial cells (VECs) were co-cultured with exosomes isolated from mesenchymal stem cells (MSCs) with transfection of miR-144-5p mimic or miR-144-5p inhibitor. IA rats were induced by combing systemic hypertension and intrathecal elastase injection. VECs were transfected with miR-144-5p mimic or inhibitor to verify the impacts of miR-144-5p on cell viability and proliferation. The connection between miR-144-5p and PTEN was verified by luciferase activity assay. Our data proved that ex-miR-144-5p was decreased in both UA and RA patients. MiR-144-5p overexpression in MSCs-derived exosome promoted VEC viability, inhibited VEC proliferation of VEs, and decreased the protein levels of matrix metalloproteinase-9 (MMP-9), proliferating cell nuclear antigen (PCNA) and osteopontin (OPN). IA rats injected with ex-miR-144-5p mimic showed significant luminal dilation, declined smooth muscle layers, and thinned vascular wall. Besides, inhibited cell apoptosis and decreased protein expressions were also observed. However, ex-miR-144-5p inhibitor had the opposite effects both in vivo and in vitro. We validated that miR-144-5p directly targeted PTEN. MiR-144-5p mimic increased cell viability and proliferation and reduced protein expressions, which could be blunted by PTEN overexpression. This study suggests that miR-144-5p elevates PTEN expression, thereby boosting apoptosis and attenuating viability of VECs in IA.

miR-let-7c-5p and miR-149-5p inhibit proinflammatory cytokine production in osteoarthritis and rheumatoid arthritis synovial fibroblasts

Osteoarthritis (OA) and rheumatoid arthritis (RA) are two of the most common types of arthritis. Both are characterized by the infiltration of a number of proinflammatory cytokines into the joint microenvironment. miRNAs play critical roles in the disease processes of arthritic disorders. However, little is known about the effects of miRNAs on critical inflammatory cytokine production with OA and RA progression. Here, we found higher levels of proinflammatory cytokines including interleukin 1 beta (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) in human OA and RA synovial fibroblasts (SFs) compared with normal SFs. Searches of open-source microRNA (miRNA) software determined that miR-let-7c-5p and miR-149-5p interfere with IL-1β, IL-6 and TNF-α transcription; levels of all three proinflammatory cytokines were lower in human OA and RA patients compared with normal controls. Anti-inflammatory agents dexamethasone, celecoxib and indomethacin reduced proinflammatory cytokine production by promoting the expression of miR-let-7c-5p and miR-149-5p. Similarly, ibuprofen and methotrexate also enhanced miR-let-7c-5p and miR-149-5p expression in human SFs. The evidence suggests that increasing miR-let-7c-5p and miR-149-5p expression is a novel strategy for OA and RA.

A sweet spot for macrophages: Focusing on polarization

Macrophages are a type of functionally plastic cells that can create a pro-/anti-inflammatory microenvironment for organs by producing different kinds of cytokines, chemokines, and growth factors to regulate immunity and inflammatory responses. In addition, they can also be induced to adopt different phenotypes in response to extracellular and intracellular signals, a process defined as M1/M2 polarization. Growing evidence indicates that glycobiology is closely associated with this polarization process. In this research, we review studies of the roles of glycosylation, glucose metabolism, and key lectins in the regulation of macrophages function and polarization to provide a new perspective for immunotherapies for multiple diseases.

Emerging roles of non-coding RNAs in the metabolic reprogramming of tumor-associated macrophages

Macrophages are the most common immune cells in the tumor microenvironment, and tumor-associated macrophages play an important role in cancer development. Metabolic reprogramming is important for the functional plasticity of macrophages. Studies investigating the relevance of non-coding RNAs (ncRNAs) in human cancer found that ncRNAs can regulate the metabolism of cancer cells and tumor-associated macrophages. NcRNAs include short ncRNAs, long ncRNAs (lncRNAs), and circular RNAs (circRNAs). The most common short ncRNAs are microRNAs, which regulate glucose, lipid, and amino acid metabolism in macrophages by acting on metabolism-related pathways and targeting metabolism-related enzymes and proteins, and are therefore involved in cancer progression. The role of lncRNAs and circRNAs in the metabolism of tumor-associated macrophages remains unclear. LncRNAs affect the glucose metabolism of macrophages, whereas their role in lipid and amino acid metabolism is not clear. CircRNAs regulate amino acid metabolism in macrophages. The roles of ncRNAs in energy metabolism and the underlying mechanisms need to be investigated further. Here, we summarize recent findings on the involvement of ncRNAs in metabolic reprogramming in tumor-associated macrophages, which affect the tumor microenvironment and play important roles in the development of cancer. Improving our understanding of the effects of ncRNAs on metabolic reprogramming of tumor-associated macrophages may facilitate the development of effective clinical therapies.

Apolipoprotein C1 (APOC1): A Novel Diagnostic and Prognostic Biomarker for Cervical Cancer

BACKGROUND

Previous reports showed that APOC1 was associated with several cancers but the function of APOC1 in cervical cancer was unknown. This study aimed to investigate the clinical effect and function of APOC1 in cervical cancer.

MATERIALS AND METHODS

In this study, the relative expression of APOC1 in cervical cancer was detected by RT-qPCR. In order to determine the cell proliferation and migration and invading ability and apoptosis more accurately, we used CCK8 assay, Edu assay, wound healing assay, migration and invasion assay, flow cytometry assay, co-immunoprecipitation, proteomics and Western blot by silencing and overexpressing APOC1, respectively. The role of APOC1 on tumor progression was explored in vitro and vivo.

RESULTS

The relative expression of APOC1 in cervical cancer tissues was up-regulated (P<0.05). In cervical cancer cell lines, silencing of APOC1 restrained cell progression and EMT, while over-expression of APOC1 accelerated cell progression and EMT in vivo and vitro (P<0.05).

CONCLUSION

APOC1 acts as an oncogene in cervical cancers and knockdown of APOC1 inhibited cervical cancer cells growth in vitro and in vivo. There is a close relationship between the relative expression of APOC1 and clinical outcome in cervical cancer patients.

TLR2 regulates angiotensin II-induced vascular remodeling and EndMT through NF-κB signaling

Excessive vascular remodeling has been shown in hypertensive patients. In experimental models of hypertensive vascular injury, such as angiotensin II (Ang II) challenged mice, toll like receptor 2 (TLR2) initiates inflammatory responses. More recently, studies have reported atypical endothelial to mesenchymal transition (EndMT) in vascular injuries and inflammatory conditions. Here, we aimed to investigate whether TLR2 mediates Ang II-induced vascular inflammation and initiates EndMT. In a mouse model of angiotensin II-induced hypertension, we show that aortas exhibit increased medial thickening, fibrosis, and features of EndMT. These alterations were not observed in TLR2 knockout mice in response to Ang II. TLR2 silencing in cultured endothelial cells confirmed the essential role of TLR2 in Ang II-induced inflammatory factor induction, and EndMT-associated phenotypic change. Mechanistically, we found Ang II activates nuclear factor-κB signaling, inducing pro-inflammatory cytokine production, and mediates EndMT in both cultured endothelial cells and in mice. These studies illustrate a novel role of TLR2 in regulating Ang II-induced deleterious vascular remodeling through the induction of EndMT. The studies also suggest that TLR2 may be targeted to alleviate hypertension-associated vascular injury.

MiR-126-5p promotes contractile switching of aortic smooth muscle cells by targeting VEPH1 and alleviates Ang II-induced abdominal aortic aneurysm in mice

Abdominal aortic aneurysm (AAA) is a potential lethal disease that is defined by an irreversible dilatation (>50%) of the aorta. During AAA expansion, the aortic wall is often remodeled, which is featured by extracellular matrix (ECM) degeneration, medial and adventitial inflammation, depletion and phenotypic switching of vascular smooth muscle cells (SMCs). Recent studies have suggested microRNAs as vital regulators for vascular SMC function. Our earlier work demonstrated an anti-AAA role of miR-126-5p in ApoE^-/- mice infused with angiotensin (Ang) II. The present study aimed to further elucidate its role in AAA pathogenesis with a focus on aortic SMC phenotypic switching. Ventricular zone expressed PH domain containing 1 (VEPH1) was identified as a novel negative regulator for vascular SMC differentiation by our group, and its expression was negatively correlated to miR-126-5p in mouse abdominal aortas based on the present microarray data. In vivo, in addition attenuating Ang II infusion-induced aortic dilation and elastin degradation, miR-126-5p agomirs also significantly reduced the expression of VEPH1. In vitro, to induce synthetic transition of human aortic smooth muscle cells (hAoSMCs), cells were stimulated with 1 μM Ang II for 24 h. Ectopic overexpression of miR-126-5p restored the differentiation of hAoSMCs-the expression of contractile/differentiated SMC markers, MYH11, and α-SMA, increased, whilst that of synthetic/dedifferentiated SMC markers, PCNA and Vimentin, decreased. Both mus and homo VEPH1 genes were validated as direct targets for miR-126-5p. VEPH1 re-expression impaired miR-126-5p-induced differentiation of hAoSMCs. In addition, Ang II-induced upregulation in matrix metalloproteinase (MMP)-9 and MMP2, two key proteases responsible for ECM degradation, in mouse aortas and hAoSMCs was reduced by miR-126-5p overexpression as well. Collectively, these results reveal an important, but previously unexplored, role of miR-126-5p in inhibiting AAA development-associated aortic SMC dedifferentiation.

Oxidized LDL Disrupts Metabolism and Inhibits Macrophage Survival by Activating a miR-9/Drp1/Mitochondrial Fission Signaling Pathway

Mitochondrial dysfunction is associated with macrophage damage, but the role of mitochondrial fission in macrophage cholesterol metabolism is not fully understood. In this study, we explored the influences of miR-9 and mitochondrial fission on macrophage viability and cholesterol metabolism. Macrophages were incubated with oxidized low-density lipoprotein (ox-LDL) in vitro, after which mitochondrial fission, cell viability, and cholesterol metabolism were examined using qPCR, ELISAs, and immunofluorescence. ox-LDL treatment significantly increased Drp1-associated mitochondrial fission. Transfection of Drp1 siRNA significantly reduced cell death, attenuated oxidative stress, and inhibited inflammatory responses in ox-LDL-treated macrophages. Interestingly, inhibition of Drp1-related mitochondrial fission also improved cholesterol metabolism by balancing the transcription of cholesterol influx/efflux enzymes. We also found that miR-9 was downregulated in ox-LDL-treated macrophages, and administration of a miR-9 mimic decreased Drp1 transcription and mitochondrial fission, as well as its effects. These results indicate that signaling via the novel miR-9/Drp1/mitochondrial fission axis is a key determinant of macrophage viability and cholesterol metabolism.

Mouse models for abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) rupture is estimated to cause 200,000 deaths each year. Currently, the only treatment for AAA is surgical repair; however, this is only indicated for large asymptomatic, symptomatic or ruptured aneurysms, is not always durable, and is associated with a risk of serious perioperative complications. As a result, patients with small asymptomatic aneurysms or who are otherwise unfit for surgery are treated conservatively, but up to 70% of small aneurysms continue to grow, increasing the risk of rupture. There is thus an urgent need to develop drug therapies effective at slowing AAA growth. This review describes the commonly used mouse models for AAA. Recent research in these models highlights key roles for pathways involved in inflammation and cell turnover in AAA pathogenesis. There is also evidence for long non-coding RNAs and thrombosis in aneurysm pathology. Further well-designed research in clinically relevant models is expected to be translated into effective AAA drugs.