Vascular Proliferative Diseases Research Articles

The Role of HIF-1α in Retinopathy of Prematurity: A Review of Current Literature.

Hypoxia-inducible factor (HIF) plays a crucial role in regulating oxygen sensing and adaptation at the cellular level, overseeing cellular oxygen homeostasis, erythrocyte production, angiogenesis, and mitochondrial metabolism. The hypoxia-sensitive HIF-1α subunit facilitates tissue adaptation to hypoxic conditions, including the stimulation of proangiogenic factors. Retinopathy of prematurity (ROP) is a proliferative vascular disease of the retina that poses a significant risk to prematurely born children. If untreated, ROP can lead to retinal detachment, severe visual impairment, and even blindness. The pathogenesis of ROP is not fully understood; however, reports suggest that premature birth leads to the exposure of immature ocular tissues to high levels of exogenous oxygen and hyperoxia, which increase the synthesis of reactive oxygen species and inhibit HIF expression. During the ischemic phase, HIF-1α expression is stimulated in the hypoxia-sensitive retina, causing an overproduction of proangiogenic factors and the development of pathological neovascularization. Given the significant role of HIF-1α in the development of ROP, considering it as a potential molecular target for therapeutic strategies appears justified. This review synthesizes information from the last six years (2018-2024) using databases such as PubMed, Google Scholar, and BASE, focusing on the role of HIF-1α in the pathogenesis of ROP and its potential as a target for new therapies.

De Novo Elastin Assembly Alleviates Development of Supravalvular Aortic Stenosis-Brief Report.

A series of incurable cardiovascular disorders arise due to improper formation of elastin during development. Supravalvular aortic stenosis (SVAS), resulting from a haploinsufficiency of ELN, is caused by improper stress sensing by medial vascular smooth muscle cells, leading to progressive luminal occlusion and heart failure. SVAS remains incurable, as current therapies do not address the root issue of defective elastin. We use SVAS here as a model of vascular proliferative disease using both human induced pluripotent stem cell-derived vascular smooth muscle cells and developmental Eln+/- mouse models to establish de novo elastin assembly as a new therapeutic intervention. We demonstrate mitigation of vascular proliferative abnormalities following de novo extracellular elastin assembly through the addition of the polyphenol epigallocatechin gallate to SVAS human induced pluripotent stem cell-derived vascular smooth muscle cells and in utero to Eln+/- mice. We demonstrate de novo elastin deposition normalizes SVAS human induced pluripotent stem cell-derived vascular smooth muscle cell hyperproliferation and rescues hypertension and aortic mechanics in Eln+/- mice, providing critical preclinical findings for the future application of epigallocatechin gallate treatment in humans.

Multi-risk factors joint prediction model for risk prediction of retinopathy of prematurity

PurposeRetinopathy of prematurity (ROP) is a retinal vascular proliferative disease common in low birth weight and premature infants and is one of the main causes of blindness in children.In the context of predictive, preventive and personalized medicine (PPPM/3PM), early screening, identification and treatment of ROP will directly contribute to improve patients’ long-term visual prognosis and reduce the risk of blindness. Thus, our objective is to establish an artificial intelligence (AI) algorithm combined with clinical demographics to create a risk model for ROP including treatment-requiring retinopathy of prematurity (TR-ROP) infants.MethodsA total of 22,569 infants who underwent routine ROP screening in Shenzhen Eye Hospital from March 2003 to September 2023 were collected, including 3335 infants with ROP and 1234 infants with TR-ROP among ROP infants. Two machine learning methods of logistic regression and decision tree and a deep learning method of multi-layer perceptron were trained by using the relevant combination of risk factors such as birth weight (BW), gestational age (GA), gender, whether multiple births (MB) and mode of delivery (MD) to achieve the risk prediction of ROP and TR-ROP. We used five evaluation metrics to evaluate the performance of the risk prediction model. The area under the receiver operating characteristic curve (AUC) and the area under the precision-recall curve (AUCPR) were the main measurement metrics.ResultsIn the risk prediction for ROP, the BW + GA demonstrated the optimal performance (mean ± SD, AUCPR: 0.4849 ± 0.0175, AUC: 0.8124 ± 0.0033). In the risk prediction of TR-ROP, reasonable performance can be achieved by using GA + BW + Gender + MD + MB (AUCPR: 0.2713 ± 0.0214, AUC: 0.8328 ± 0.0088).ConclusionsCombining risk factors with AI in screening programs for ROP could achieve risk prediction of ROP and TR-ROP, detect TR-ROP earlier and reduce the number of ROP examinations and unnecessary physiological stress in low-risk infants. Therefore, combining ROP-related biometric information with AI is a cost-effective strategy for predictive diagnostic, targeted prevention, and personalization of medical services in early screening and treatment of ROP.

Urotensin II receptor deficiency ameliorates ligation-induced carotid intimal hyperplasia partially through the RhoA-YAP1 pathway

Intimal hyperplasia (IH) is a common pathological feature of vascular proliferative diseases, such as atherosclerosis and restenosis after angioplasty. Urotensin II (UII) and its receptor (UTR) are widely expressed in cardiovascular tissues. However, it remains unclear whether the UII/UTR system is involved in IH. Right unilateral common carotid artery ligation was performed and maintained for 21 days to induce IH in UTR knockout (UTR−/−) and wild-type (WT) mice. Histological analysis revealed that compared with WT mice, UTR-deficient mice exhibited a decreased neointimal area, angiostenosis and intima–media ratio. Immunostaining revealed fewer smooth muscle cells (SMCs), endothelial cells and macrophages in the lesions of UTR−/− mice than in those of WT mice. Protein interaction analysis suggested that the UTR may affect cell proliferation by regulating YAP and its downstream target genes. In vitro experiments revealed that UII can promote the proliferation and migration of SMCs, and western blotting also revealed that UII increased the protein expression of RhoA, CTGF, Cyclin D1 and PCNA and downregulated p-YAP protein expression, while these effects could be partly reversed by urantide. To evaluate the translational value of UTRs in IH management, WT mice were also treated with two doses of urantide, a UTR antagonist, to confirm the benefit of UTR blockade in IH progression. A high dose of urantide (600 μg/kg/day), rather than a low dose (60 μg/kg/day), successfully improved ligation-induced IH compared with that in mice receiving vehicle. The results of the present study suggested that the UII/UTR system may regulate IH partly through the RhoA-YAP signaling pathway.

Disturbed flow regulates protein disulfide isomerase A1 expression via microRNA-204.

Redox processes can modulate vascular pathophysiology. The endoplasmic reticulum redox chaperone protein disulfide isomerase A1 (PDIA1) is overexpressed during vascular proliferative diseases, regulating thrombus formation, endoplasmic reticulum stress adaptation, and structural remodeling. However, both protective and deleterious vascular effects have been reported for PDIA1, depending on the cell type and underlying vascular condition. Further understanding of this question is hampered by the poorly studied mechanisms underlying PDIA1 expression regulation. Here, we showed that PDIA1 mRNA and protein levels were upregulated (average 5-fold) in the intima and media/adventitia following partial carotid ligation (PCL). Our search identified that miR-204-5p and miR-211-5p (miR-204/211), two broadly conserved miRNAs, share PDIA1 as a potential target. MiR-204/211 was downregulated in vascular layers following PCL. In isolated endothelial cells, gain-of-function experiments of miR-204 with miR mimic decreased PDIA1 mRNA while having negligible effects on markers of endothelial activation/stress response. Similar effects were observed in vascular smooth muscle cells (VSMCs). Furthermore, PDIA1 downregulation by miR-204 decreased levels of the VSMC contractile differentiation markers. In addition, PDIA1 overexpression prevented VSMC dedifferentiation by miR-204. Collectively, we report a new mechanism for PDIA1 regulation through miR-204 and identify its relevance in a model of vascular disease playing a role in VSMC differentiation. This mechanism may be regulated in distinct stages of atherosclerosis and provide a potential therapeutic target.

Pharmacological inhibition of MALT1 (mucosa-associated lymphoid tissue lymphoma translocation protein 1) induces ferroptosis in vascular smooth muscle cells

MALT1 (mucosa-associated lymphoid tissue lymphoma translocation protein 1) is a human paracaspase protein with proteolytic activity via its caspase-like domain. The pharmacological inhibition of MALT1 by MI-2, a specific chemical inhibitor, diminishes the response of endothelial cells to inflammatory stimuli. However, it is largely unknown how MALT1 regulates the functions of vascular smooth muscle cells (SMCs). This study aims to investigate the impact of MALT1 inhibition by MI-2 on the functions of vascular SMCs, both in vitro and in vivo. MI-2 treatment led to concentration- and time-dependent cell death of cultured aortic SMCs, which was rescued by the iron chelator deferoxamine (DFO) or ferrostatin-1 (Fer-1), a specific inhibitor of ferroptosis, but not by inhibitors of apoptosis (Z-VAD-fmk), pyroptosis (Z-YVAD-fmk), or necrosis (Necrostatin-1, Nec-1). MI-2 treatment downregulated the expression of glutathione peroxidase 4 (GPX4) and ferritin heavy polypeptide 1 (FTH1), which was prevented by pre-treatment with DFO or Fer-1. MI-2 treatment also activated autophagy, which was inhibited by Atg7 deficiency or bafilomycin A1 preventing MI-2-induced ferroptosis. MI-2 treatment reduced the cleavage of cylindromatosis (CYLD), a specific substrate of MALT1. Notably, MI-2 treatment led to a rapid loss of contractility in mouse aortas, which was prevented by co-incubation with Fer-1. Moreover, local application of MI-2 significantly reduced carotid neointima lesions and atherosclerosis in C57BL/6J mice and apolipoprotein-E knockout (ApoE−/−) mice, respectively, which were both ameliorated by co-treatment with Fer-1. In conclusion, the present study demonstrated that MALT1 inhibition induces ferroptosis of vascular SMCs, likely contributing to its amelioration of proliferative vascular diseases.

Abstract 13109: Empagliflozin Reverses Oxidized LDL-Induced RECK Suppression, MMP Activation, and Human Aortic Smooth Muscle Cell Proliferation and Migration

Empagliflozin, an FDA-approved anti-hyperglycemic agent, is a potent and highly selective inhibitor of sodium glucose co-transporter-2 (SGLT-2) in renal proximal tubule epithelial cells. It blocks glucose reabsorption and promotes glucose excretion via urine. Intriguingly, several clinical trials have reported the pleiotropic beneficial effects of SGLT-2 inhibitors in cardiovascular diseases, including antioxidant and anti-inflammatory effects. Here we investigated whether empagliflozin reverses oxidatively modified LDL (OxLDL)-induced matrix metalloproteinase activation and smooth muscle cell (SMC) migration and proliferation. Quiesced human aortic SMCs (Lonza) were treated with empagliflozin (1 uM) followed by human medium OxLDL (40 ug/mL; Kalen Biomedical). OxLDL stimulated SMC migration (1.8-fold, P<0.05, n=4) and proliferation (1.5-fold, P<0.05, n=4), and empagliflozin attenuated both by 67% (P<0.05, n=4) and 61% (P<0.05, n=4), respectively. Increased migration and proliferation by OxLDL were accompanied by elevated MMP-2 (3.2-fold, P<0.05, n=5) and 9 (3.1-fold, P<0.05, n=5) activities, which were also suppressed by empagliflozin by 65% and 67%, respectively (both P<0.05, n=5). RECK (reversion inducing cysteine rich protein with Kazal motifs) is a membrane anchored MMP inhibitor, and we found that OxLDL dose-dependently downregulated RECK in SMCs (by 60%, P<0.05, n=3) via NF-kB-dependent miR-30b induction. Intriguingly, empagliflozin restored the OxLDL downregulation of RECK to 88% of the control (n=3), as it inhibited miR-30b induction (by 49%, P<0.05, n=5). Consistent with RECK-mediated effects of empagliflozin, adenoviral overexpression of RECK inhibited OxLDL-induced SMC migration (by 67%, P<0.05, n=5) and proliferation (by 50%, P<0.05, n=5). Together, these results suggest that the vasculoprotective effects of empagliflozin are at least in part mediated by restoring RECK, thereby attenuating SMC migration and proliferation under elevated oxidative stress condition. Our results also suggest therapeutic potential of empagliflozin or RECK overexpression in vascular proliferative diseases.

Abstract 12872: Epigenetic Regulation of Vascular Smooth Muscle Cell Phenotypic Switch and Neointimal Formation by PRMT5

Rationale: Phenotypic transition of vascular smooth muscle cells (VSMCs) from a contractile to a synthetic state is involved in the development of cardiovascular diseases, including atherosclerosis, hypertension, and post-angioplasty restenosis. Arginine methylation catalyzed by protein arginine methyltransferases (PRMTs) has been implicated in multiple cellular processes, however, its role in VSMC biology remains undetermined. Objective: To determine the role of PRMTs in VSMC phenotypic switch and vascular remodeling after injury. Methods and Results: Our results show that PRMT5 is the most abundantly expressed PRMT in human aortic SMCs, and its expression is upregulated in platelet-derived growth factor (PDGF)-stimulated VSMCs, human atherosclerotic lesions, and rat carotid arteries after injury, as determined by western blot and immunohistochemical staining. PRMT5 overexpression inhibits the expression of SMC marker genes, and promotes VSMC proliferation and migration, while silencing PRMT5 exerts the opposite effects. Mechanistically, we found that PRMT5 overexpression led to histone di-methylation of H3R8 and H4R3, which in turn attenuates acetylation of H3K9 and H4, thus limiting recruitment of the SRF/myocardin complexes to the CArG boxes of SMC marker genes. Furthermore, both SMC-specific deletion of PRMT5 in mice and local delivery of lentivirus expressing shPRMT5 to rat carotid arteries significantly attenuated neointimal formation after injury. Likewise, pharmacological inhibition of PRMT5 by EPZ015666 markedly inhibited carotid artery ligation-induced neointimal formation in mice. Conclusions: Our results identify PRMT5 as a novel regulator in VSMC phenotypic switch and suggest that inhibition of PRMT5 may represent an effective therapeutic strategy for proliferative vascular diseases.

Empagliflozin Reverses Oxidized LDL-Induced RECK Suppression, Cardiotrophin-1 Expression, MMP Activation, and Human Aortic Smooth Muscle Cell Proliferation and Migration.

Persistent oxidative stress and inflammation contribute causally to smooth muscle cell (SMC) proliferation and migration, the characteristic features of vascular proliferative diseases. Oxidatively modified low-density lipoproteins (OxLDL) elevate oxidative stress levels, inflammatory responses, and matrix metallopeptidase (MMP) activation, resulting ultimately in SMC migration, proliferation, and phenotype change. Reversion-inducing cysteine-rich protein with Kazal motifs (RECK) is a membrane-anchored MMP inhibitor. Empagliflozin is an SGLT2 inhibitor and exerts pleiotropic cardiovascular protective effects, including antioxidant and anti-inflammatory effects. Here, we investigated (i) whether OxLDL regulates RECK expression, (ii) whether ectopic expression of RECK reverses OxLDL-induced SMC migration and proliferation, and (iii) whether pretreatment with empagliflozin reverses OxLDL-induced RECK suppression, MMP activation, and SMC migration, proliferation, and differentiation. Indeed, results show that OxLDL at pathophysiological concentration promotes SMC migration and proliferation via NF-κB/miR-30b-dependent RECK suppression. Moreover, OxLDL changed the SMC phenotype to a more pro-inflammatory type, and this effect is blunted by RECK overexpression. Further, treatment with empagliflozin reversed OxLDL-induced miR-30b induction, RECK suppression, MMP activation, SMC migration, proliferation, and proinflammatory phenotype changes. OxLDL-induced cardiotrophin (CT)-1 expression and CT-1 stimulated SMC proliferation and migration in part via leukemia inhibitory factor receptor (LIFR) and glycoprotein 130 (gp130). Ectopic expression of RECK inhibited these effects by physically associating with LIFR and gp130, as evidenced by immunoprecipitation/immunoblotting and double immunofluorescence. Importantly, empagliflozin inhibited CT-1-induced mitogenic and migratory effects. Together, these results suggest the therapeutic potential of sustaining RECK expression or empagliflozin in vascular diseases characterized by SMC proliferation and migration.

The innate immune sensor STING accelerates neointima formation via NF-κB signaling pathway.

Vascular smooth muscle cells (VSMCs) proliferation, migration, and phenotypic switching are considered crucial events in the progression of neointima formation. Stimulator of interferon genes (STING), an innate immune sensor of cyclic dinucleotides against pathogens, in neointima formation remains obscure. Here, we observed a significant increase in STING expression on the neointima of injured vessels and mouse aortic VSMCs induced by PDGF-BB. In vivo, global knockout of STING (Sting-/-) attenuated neointima formation after vascular injury. In vitro data showed that STING deficiency significantly alleviated PDGF-BB-induced proliferation and migration in VSMCs. Furthermore, these contractile marker genes were upregulated in Sting-/- VSMCs. Overexpression of STING promoted proliferation, migration, and phenotypic switching in VSMCs. Mechanistically, STING-NF-κB signaling was involved in this process. The pharmacological inhibition of STING induced by C-176 partially prevented neointima formation due to suppression of VSMCs proliferation. Taken together, STING-NF-κB axis significantly promoted proliferation, migration, and phenotypic switching of VSMCs, which may be a novel therapeutic approach to combat vascular proliferative diseases.

Epigenetic regulation of vascular smooth muscle cell phenotypic switch and neointimal formation by PRMT5.

Phenotypic transition of vascular smooth muscle cells (VSMCs) from a contractile to a synthetic state is involved in the development of cardiovascular diseases, including atherosclerosis, hypertension, and post-angioplasty restenosis. Arginine methylation catalyzed by protein arginine methyltransferases (PRMTs) has been implicated in multiple cellular processes, however, its role in VSMC biology remains undetermined. The objective of this study was to determine the role of PRMTs in VSMC phenotypic switch and vascular remodeling after injury. Our results show that PRMT5 is the most abundantly expressed PRMT in human aortic SMCs, and its expression is upregulated in platelet-derived growth factor (PDGF)-stimulated VSMCs, human atherosclerotic lesions, and rat carotid arteries after injury, as determined by western blot and immunohistochemical staining. PRMT5 overexpression inhibits the expression of SMC marker genes, and promotes VSMC proliferation and migration, while silencing PRMT5 exerts the opposite effects. Mechanistically, we found that PRMT5 overexpression led to histone di-methylation of H3R8 and H4R3, which in turn attenuates acetylation of H3K9 and H4, thus limiting recruitment of the SRF/myocardin complexes to the CArG boxes of SMC marker genes. Furthermore, both SMC-specific deletion of PRMT5 in mice and local delivery of lentivirus expressing shPRMT5 to rat carotid arteries significantly attenuated neointimal formation after injury. Likewise, pharmacological inhibition of PRMT5 by EPZ015666 markedly inhibited carotid artery ligation-induced neointimal formation in mice. Our results identify PRMT5 as a novel regulator in VSMC phenotypic switch and suggest that inhibition of PRMT5 may represent an effective therapeutic strategy for proliferative vascular diseases.

The downstream network of STAT6 in promoting vascular smooth muscle cell phenotypic switch and neointimal formation.

Intimal thickening caused by the excessive multiplication of vascular smooth muscle cells (VSMCs) is the pathological process central to cardiovascular diseases, including restenosis. In response to vascular injury, VSMCs would undergo phenotypic switching from a fully differentiated, low proliferative rate phenotype to a more pro-proliferative, promigratory, and incompletely-differentiated state. The lack of a full understanding of the molecular pathways coupling the vascular injury stimuli to VSMCs phenotype switching largely limits the development of medical therapies for treating intima hyperplasia-related diseases. The role of signal transducers and activators of transcription 6 (STAT6) in modulating the proliferation and differentiation of various cell types, especially macrophage, has been well investigated, but little is known about its pathophysiological role and target genes in restenosis after vascular injury. In the present work, Stat6-/- mice were observed to exhibit less severe intimal hyperplasia compared with Stat6+/+ mice after carotid injury. The expression of STAT6 was upregulated in VSMCs located in the injured vascular walls. STAT6 deletion leads to decreased proliferation and migration of VSMCs while STAT6 overexpression enhances the proliferation and migration of VSMCs companies with reduced expression of VSMCs marker genes and organized stress fibers. The effect of STAT6 in mouse VSMCs was conserved in human aortic SMCs. RNA-deep-sequencing and experiments verification revealed LncRNA C7orf69/LOC100996318-miR-370-3p/FOXO1-ER stress signaling as the downstream network mediating the pro-dedifferentiation effect of STAT6 in VSMCs. These findings broaden our understanding of vascular pathological molecules and throw a beam of light on the therapy of a variety of proliferative vascular diseases.

Inflachromene inhibits intimal hyperplasia through the HMGB1/2- regulated TLR4-NF-κB pathway

The contractile-syntheticphenotypicconversion of vascular smooth muscle cells (VSMCs) plays a key role in atherosclerosis, vascular restenosis, and hypertension. Our previous study explored the correlation between high mobility group box protein (HMGB) 1 and HMGB2 and neointimal hyperplasia after vascular injury. In the present study, we explore whether inflachromene (ICM), a novel inhibitor of the expression of both HMGB1 and HMGB2, modulates phenotypic changes in VSMCs and the mechanisms involved. Mice treated with ICM after carotid artery wire injury showed a decrease in excessive neointimal hyperplasia compared with that in the vehicle groups. In cultured VSMCs, pretreatment with ICM suppressed the angiotensin II (Ang II)-induced phenotypic conversion, proliferation, and migration. We discovered that ICM reduced the Ang II-induced upregulation of the expression of HMGB1 and HMGB2 and inhibited their shuttling between the nucleus and the cytosol. Mechanistically, Ang II-treated VSMCs exhibited higher levels of Toll-like receptor 4 (TLR4) and nuclear factor-κB (NF-κB) phosphorylation, which were attenuated by ICM. In addition, the NF-κB inhibitor Bay-117082 abolished the recombinant HMGB1-mediated VSMC phenotypic conversion, proliferation, and migration. Furthermore, ICM ameliorated the Ang II-induced increases in NAD[P]H oxidase expression, thereby attenuating the Ang II-induced proliferation and migration. These results reveal that ICM pretreatment attenuates Ang II-induced VSMC dedifferentiation, proliferation, and migration may by regulating the TLR4-NF-kB pathway. Thus, ICM is a potential therapy and preventive treatment for vascular proliferative diseases.

Long-term hemodynamic changes in cerebral proliferative angiopathy presenting with intracranial hemorrhage: illustrative case.

Cerebral proliferative angiopathy (CPA) is a rare vascular proliferative disease; however, long-term follow-up reports are scarce. The authors report a rare case and document a patient's medical history over 20 years. A 5-year-old girl developed left frontal lobe hemorrhage, presenting with headache. At 8 years of age, angiography showed diffuse capillary ectasia without an arteriovenous shunt. Single-photon emission computed tomography (SPECT) showed normal cerebral blood flow (CBF). She had normal growth without systemic disease. At 25 years of age, an intraventricular hemorrhage occurred, presenting with sudden headache. Angiography revealed vascular lesion enlargement, increased feeding arteries, dural supply to the nidus and peri-nidal lesion, and flow-related aneurysm. SPECT showed remarkable decreases in CBF in the nidus and peri-nidal lesion. Cerebral proliferative angiopathy (CPA) was diagnosed, and the aneurysm arising at the lateral posterior choroidal artery caused the hemorrhage. Coil embolization of the aneurysm was performed with a flow-guide catheter and extremely soft platinum coils. New aneurysms were not noted 1.5 years after the procedure. This is the first report to demonstrate hemodynamic changes in CPA on angiography and SPECT over 17 years. The development of endovascular devices has enabled the embolization of ruptured aneurysms at the peripheral cerebral artery.

Standardize the laser and anti-vascular endothelial growth factor treatment of retinopathy of prematurity

Retinopathy of prematurity (ROP) is a retinal vascular proliferative disease occurring in premature and low birth weight infants, which is the leading cause of blindness and low vision in children. Laser photocoagulation is still recognized as the gold standard of treatment in ROP. Recently, anti-vascular endothelial growth factor (VEGF) therapy has become a novel alternative approach in clinical practice for ROP. However, there are still many improper and deviations in identifying indications and selecting therapeutic modalities, resulting in generalization and abuse of anti-VEGF drugs in treatment of ROP. The aim of this article is to summarize and objectively evaluate the treatment indications and methods of ROP based on related research at home and abroad, in order to strictly control the theraputic indications and scientifically and rigorously select appropriate therapeutic modalities for the benefit of children with ROP.

Polo-like kinase 4 inhibitor CFI-400945 inhibits carotid arterial neointima formation but increases atherosclerosis

Neointima lesion and atherosclerosis are proliferative vascular diseases associated with deregulated proliferation of vascular smooth muscle cells (SMCs). CFI-400945 is a novel, highly effective anticancer drug that inhibits polo-like kinase 4 (PLK4) and targets mitosis. In this study, we aim to investigate how CFI-400945 affects the development of proliferative vascular diseases. In C57BL/6 mice, neointima formation was generated by complete carotid ligation. In apolipoprotein E knockout (ApoE−/−) mice fed a high-fat diet, atherosclerosis was induced by partial carotid ligation. CFI-400945 was directly applied to carotid arteries via a perivascular collar. Our results showed that CFI-400945 drastically inhibited neointima formation but significantly accelerated atherosclerosis. In vitro studies showed that CFI-400945 treatment induced SMC polyploidization and arrested cells in the G2/M phase. CFI-400945 treatment upregulated p53 and p27 expression but decreased p21 and cyclin B1 expression. CFI-400945 also induced SMC apoptosis, which was inhibited by hydroxyurea, a DNA synthesis inhibitor that inhibits polyploidization. Furthermore, CFI-400945 caused supernumerary centrosomes, leading to mitotic failure, resulting in polyploidization. In conclusion, CFI-400945 prevents carotid arterial neointima formation in C57BL/6 mice but accelerates atherosclerosis in ApoE−/− mice, likely through mitotic arrest and subsequent induction of polyploidization and apoptosis.

GabROP: Gabor Wavelets-Based CAD for Retinopathy of Prematurity Diagnosis via Convolutional Neural Networks.

One of the most serious and dangerous ocular problems in premature infants is retinopathy of prematurity (ROP), a proliferative vascular disease. Ophthalmologists can use automatic computer-assisted diagnostic (CAD) tools to help them make a safe, accurate, and low-cost diagnosis of ROP. All previous CAD tools for ROP diagnosis use the original fundus images. Unfortunately, learning the discriminative representation from ROP-related fundus images is difficult. Textural analysis techniques, such as Gabor wavelets (GW), can demonstrate significant texture information that can help artificial intelligence (AI) based models to improve diagnostic accuracy. In this paper, an effective and automated CAD tool, namely GabROP, based on GW and multiple deep learning (DL) models is proposed. Initially, GabROP analyzes fundus images using GW and generates several sets of GW images. Next, these sets of images are used to train three convolutional neural networks (CNNs) models independently. Additionally, the actual fundus pictures are used to build these networks. Using the discrete wavelet transform (DWT), texture features retrieved from every CNN trained with various sets of GW images are combined to create a textural-spectral-temporal demonstration. Afterward, for each CNN, these features are concatenated with spatial deep features obtained from the original fundus images. Finally, the previous concatenated features of all three CNN are incorporated using the discrete cosine transform (DCT) to lessen the size of features caused by the fusion process. The outcomes of GabROP show that it is accurate and efficient for ophthalmologists. Additionally, the effectiveness of GabROP is compared to recently developed ROP diagnostic techniques. Due to GabROP's superior performance compared to competing tools, ophthalmologists may be able to identify ROP more reliably and precisely, which could result in a reduction in diagnostic effort and examination time.

DNA-Dependent Protein Kinase Mediates YB-1 (Y-Box Binding Protein)-Induced Double Strand Break Repair.

DNA-PK (DNA-dependent protein kinase) is a stress-activated serine/threonine kinase that plays a central role in vascular smooth muscle cell proliferation and vascular proliferative disease processes such as neointimal formation. In this study, we link the activation of DNA-PK to the function of the transcription factor YB-1 (Y-box binding protein). To identify YB-1 phosphorylation by DNA-PK, we generated different YB-1-expressing vectors. YB-1 nuclear translocation was investigated using immunoblotting and immunofluorescence staining. For YB-1 activity, luciferase assays were performed. We show by mutational analysis and kinase assay that the transcriptional regulator YB-1 is a substrate of DNA-PK. Blockade of DNA-PK by specific inhibitors revealed its critical involvement in YB-1phosphorylation as demonstrated by inhibition of an overexpressed YB-1 reporter construct. Using DNA-PK-deficient cells, we demonstrate that the shuttling of YB-1 from the cytoplasm to the nucleus is dependent on DNA-PK and that the N-terminal domain of YB-1 is phosphorylated at threonine 89. Point mutation of YB-1 at this residue abrogated the translocation of YB-1 into the nucleus. The phosphorylation of YB-1 by DNA-PK increased cellular DNA repair after exposure to ionizing radiation. Atherosclerotic tissue specimens were analyzed by immunohistochemistry. The DNA-PK subunits and YB-1 phosphorylated at T89 were found colocalized suggesting their in vivo interaction. In mice, the local application of the specific DNA-PK inhibitor NU7026 via thermosensitive Pluronic F-127 gel around dilated arteries significantly reduced the phosphorylation of YB-1. DNA-PK directly phosphorylates YB-1 and, this way, modulates YB-1 function. This interaction could be demonstrated in vivo, and colocalization in human atherosclerotic plaques suggests clinical relevance of our finding. Phosphorylation of YB-1 by DNA-PK may represent a novel mechanism governing atherosclerotic plaque progression.

Methyltransferase like 3-mediated N6-methylatidin methylation inhibits vascular smooth muscle cells phenotype switching via promoting phosphatidylinositol 3-kinase mRNA decay.

N6-methylatidine (m6A) is involved in post-transcriptional metabolism and a variety of pathological processes. However, little is known about the role of m6A in vascular proliferative diseases, particularly in vascular smooth muscle cells (VSMCs) phenotype switching-induced neointimal hyperplasia. In the current study, we discovered that methyltransferase like 3 (METTL3) is a critical candidate for catalyzing a global increase in m6A in response to carotid artery injury and various VSMCs phenotype switching. The inhibited neointimal hyperplasia was obtained after in vivo gene transfer to knock-down Mettl3. In vitro overexpression of Mettl3 resulted in increased VSMC proliferation, migration, and reduced contractile gene expression with a global elevation of m6A modification. In contrast, Mettl3 knockdown reversed this facilitated phenotypic switch in VSMCs, as demonstrated by downregulated m6A, decreased proliferation, migration, and increased expression of contractile genes. Mechanistically, Mettl3 knock-down was found to promote higher phosphatidylinositol 3-kinase (Pi3k) mRNA decay thus inactivating the PI3K/AKT signal to inhibit VSMCs phenotype switching. Overall, our findings highlight the importance of METTL3-mediated m6A in VSMCs phenotype switching and offer a novel perspective on targeting METTL3 as a therapeutic option for VSMCs phenotype switching modulated pathogenesis, including atherosclerosis and restenosis.

Piezo1 in vascular remodeling of atherosclerosis and pulmonary arterial hypertension: A potential therapeutic target.

Vascular remodeling (VR) is a structural and functional change of blood vessels to adapt to the changes of internal and external environment. It is one of the common pathological features of many vascular proliferative diseases. The process of VR is mainly manifested in the changes of vascular wall structure and function, including intimal hyperplasia, thickening or thinning of media, fibrosis of adventitia, etc. These changes are also the pathological basis of aging and various cardiovascular diseases. Mechanical force is the basis of cardiovascular biomechanics, and the newly discovered mechanical sensitive ion channel Piezo1 is widely distributed in the whole cardiovascular system. Studies have confirmed that Piezo1, a mechanically sensitive ion channel, plays an important role in cardiovascular remodeling diseases. This article reviews the molecular mechanism of Piezo1 in atherosclerosis, hypertension and pulmonary hypertension, in order to provide a theoretical basis for the further study of vascular remodeling.