Yes-associated protein promotes endothelial-tomesenchymal transition of endothelial cells in choroidal neovascularization fibrosis

AIM:To reveal whether and how Yes-associated protein(YAP)promotes the occurrence of subretinal fibrosis in agerelated macular degeneration(AMD).METHODS:Cobalt chloride(Co Cl2)was used in primary human umbilical vein endothelial cells(HUVECs)to induce hypoxia in vitro.Eight-week-old male C57 BL/6 J mice weighing 19-25 g were used for a choroidal neovascularization(CNV)model induced by laser photocoagulation in vivo.Expression levels of YAP,phosphorylated YAP,mesenchymal markers[αsmooth muscle actin(α-SMA),vimentin,and Snail],and endothelial cell markers(CD31 and zonula occludens 1)were measured by Western blotting,quantitative real-time PCR,and immunofluorescence microscopy.Small molecules YC-1(Lificiguat,a specific inhibitor of hypoxia-inducible factor 1α),CA3(CIL56,an inhibitor of YAP),and XMU-MP-1(an inhibitor of Hippo kinase MST1/2,which activates YAP)were used to explore the underlying mechanism.RESULTS:Co Cl2 increased expression of mesenchymal markers,decreased expression of endothelial cell markers,and enhanced the ability of primary HUVECs to proliferate and migrate.YC-1 suppressed hypoxia-induced endothelialto-mesenchymal transition(End MT).Moreover,hypoxia promoted total expression,inhibited phosphorylation,and enhanced the transcriptional activity of YAP.XMU-MP-1 enhanced hypoxia-induced End MT,whereas CA3 elicited the opposite effect.Expression of YAP,α-SMA,and vimentin were upregulated in the laser-induced CNV model.However,silencing of YAP by vitreous injection of small interfering RNA targeting YAP could reverse these changes.CONCLUSION:The findings reveal a critical role of the hypoxia-inducible factor-1α(HIF-1α)/YAP signaling axis in End MT and provide a new therapeutic target for treatment of subretinal fibrosis in AMD.

Morin,a matrix metalloproteinase 9 inhibitor,attenuates endothelial-to-mesenchymal transition in atherosclerosis by downregulating Notch-1 signaling

Objective:Atherosclerotic cardiovascular disease poses a significant health challenge globally.Recent findings highlight the pivotal role of the endothelial-to-mesenchymal transition(End MT)in atherosclerosis.Morin is a bioflavonoid mainly extracted from white mulberry,a traditional Chinese herbal medicine with anti-inflammatory and antioxidant properties.This study examines whether morin can alleviate atherosclerosis by suppressing End MT and seeks to elucidate the underlying mechanism.Methods:We induced an in vitro End MT model in human umbilical vein endothelial cells(HUVECs)by stimulating the cells with transforming growth factor-β1(TGF-β1)(10 ng/m L)for 48 h.The in vivo experiments were performed in an atherosclerosis model using apolipoprotein E(Apo E)^(-/-)mice fed with a high-fat diet(HFD).Mice in the intervention group were given morin(50 mg/kg)orally for 4 weeks.Molecular docking and microscale thermophoresis were assayed to understand the interactions between morin and matrix metalloproteinase-9(MMP-9).Results:Morin inhibited the expression of End MT markers in a dose-dependent manner in TGF-β1-treated HUVECs.Administering 50μmol/L morin suppressed the upregulation of MMP-9 and Notch-1 signaling in TGF-β1-induced End MT.Moreover,the overexpression of MMP-9 activated Notch-1 signaling,thereby reversing morin's inhibitory effect on End MT.In the HFD-induced atherosclerotic Apo E^(-/-)mice,morin notably reduced aortic intimal hyperplasia and plaque formation by suppressing End MT.Furthermore,morin demonstrated a strong binding affinity for MMP-9.Conclusion:Morin acts as an MMP-9 inhibitor to disrupt End MT in atherosclerosis by limiting the activation of Notch-1 signaling.This study underscores morin's potential utility in the development of antiatherosclerotic medication.

Endothelial phosphodiesterase 4B inactivation ameliorates endothelial-to-mesenchymal transition and pulmonary hypertension

Pulmonary hypertension (PH) is a fatal disorder characterized by pulmonary vascular remodeling and obstruction. The phosphodiesterase 4 (PDE4) family hydrolyzes cyclic AMP (cAMP) and is comprised of four subtypes (PDE4A–D). Previous studies have shown the beneficial effects of pan-PDE4 inhibitors in rodent PH;however, this class of drugs is associated with side effects owing to the broad inhibition of all four PDE4 isozymes. Here, we demonstrate that PDE4B is the predominant PDE isozyme in lungs and that it was upregulated in rodent and human PH lung tissues. We also confirmed that PDE4B is mainly expressed in the lung endothelial cells (ECs). Evaluation of PH in Pde4b wild type and knockout mice confirmed that Pde4b is important for the vascular remodeling associated with PH. In vivo EC lineage tracing demonstrated that Pde4b induces PH development by driving endothelial-to-mesenchymal transition (EndMT), and mechanistic studies showed that Pde4b regulates EndMT by antagonizing the cAMP-dependent PKA–CREB–BMPRII axis. Finally, treating PH rats with a PDE4B-specific inhibitor validated that PDE4B inhibition has a significant pharmacological effect in the alleviation of PH. Collectively, our findings indicate a critical role for PDE4B in EndMT and PH, prompting further studies of PDE4B-specific inhibitors as a therapeutic strategy for PH.

Oxidative stress mediates glycidol-induced endothelial injury and its protection by 6-C-(E-2-fluorostyryl)naringenin

Glycidol is a common lipid-derived foodborne toxicant mainly presents in refined oils and related foodstuffs.Vascular endothelial cells may be potential targets of the deleterious effects associated with glycidol exposure.In human umbilical vein endothelial cells(HUVECs),we found that glycidol treatment promoted endothelialto-mesenchymal transition(EndMT)at a lower concentration(0.5 mmol/L),while induced apoptosis and inflammation at a higher concentration(1 mmol/L).These harmful effects were achieved by the activation of NF-κB/MAPK signaling pathway and were mediated by reactive oxygen species(ROS).In addition,the protective potential of 6-C-(E-2-fluorostyryl)naringenin(6-CEFN)against glycidol was evaluated and compared with naringenin.HUVECs pre-treated with 6-CEFN,but not naringenin,displayed resistance to endothelial dysfunction caused by glycidol.

敲低前蛋白转化酶枯草溶菌素9(PCSK9)抑制人主动脉内皮细胞的内皮间质转化

目的以人主动脉内皮细胞(HAEC)为研究对象,探讨敲减前蛋白转化酶枯草溶菌素9(PCSK9)对β甘油磷酸、地塞米松、L-抗坏血酸诱导内皮间质转化(EndoMT)的保护作用。方法以(0、10、30、50)mmol/Lβ甘油磷酸联合100 nmol/L地塞米松和50μg/ml L-抗坏血酸诱导HAEC建立EndoMT模型。采用PCSK9的特异性小干扰RNA(si-PCSK9)转染HAEC,实时荧光定量PCR与Western blot法检测HAEC的PCSK9的mRNA和蛋白表达。将HAEC随机分为空白组、EndoMT组、转染阴性对照小干扰RNA的EndoMT组、转染si-PCSK9的EndoMT组。实时荧光定量PCR检测α平滑肌肌动蛋白(α-SMA)、成纤维细胞特异蛋白1(FSP1)、血管内皮钙黏蛋白(VE-cadherin)的mRNA水平,Western blot法检测α-SMA、VE-cadherin的蛋白水平,免疫荧光染色法检测α-SMA的表达。结果30 mmol/Lβ甘油磷酸诱导EndoMT效果最佳,发生EndoMT时,PCSK9的mRNA及蛋白表达上调。而PCSK9敲减后,α-SMA、FSP1的表达下调,VE-cadherin的表达上调。结论敲低PCSK9可抑制HAEC的EndoMT。

内皮间质转化在胶质瘤中的研究现状及其靶向治疗策略

内皮间质转化(EndoMT)是指在一定的刺激因素作用下,内皮细胞失去其特征性表型、功能及形态而逐渐向间质细胞转化的一种病理生理过程。越来越多的研究表明,EndoMT在胶质瘤的发生发展及侵袭转移等病理过程中发挥着关键作用,本文综述了EndoMT相关信号通路及其在胶质瘤异常血管生成、侵袭转移、免疫抑制、耐药等方面的重要作用,总结了以其为靶点的治疗策略,为研究其在胶质瘤发生发展及治疗中的作用提供理论基础和科学依据,为临床治疗该病提供参考。

Construction of tissue-engineered vascular grafts with enhanced patency by integrating heparin,cell-adhesive peptide,and carbon monoxide nanogenerators into acellular blood vessels

Small-diameter tissue-engineered vascular grafts(sdTEVGs)have garnered significant attention as a potential treatment modality for vascular bypass grafting and replacement therapy.However,the intimal hyperplasia and thrombosis are two major complications that impair graft patency during transplantation.To address this issue,we fabricated the covalent-organic framework(COF)-based carbon monoxide(CO)nanogenerator-and co-immobilized with LXW-7 peptide and heparin to establish a multifunctional surface on TEVGs constructed from acellular blood vessels for preventing thrombosis and stenosis.The cell-adhesive peptide LXW-7 could capture endothelial-forming cells(EFCs)to promote endothelialization,while the antithrombotic molecule heparin prevented thrombus formation.The reactive oxygen species(ROS)-triggered CO release suppressed the adhesion and activation of macrophages,leading to the reduction of ROS and inflammatory factors.As a result,the endothelial-to-mesenchymal transition(EndMT)triggered by inflammation was restricted,facilitating the maintenance of the homeostasis of the neo-endothelium and preventing pathological remodeling in TEVGs.When transplanted in vivo,these vascular grafts exhibited negligible intimal hyperplasia and remained patent for 3 months.This achievement provided a novel approach for constructing antithrombotic and anti-hyperplastic TEVGs.

Notch信号与卡波西肉瘤相关疱疹病毒关系的研究进展

卡波西肉瘤相关疱疹病毒(Kaposi's sarcoma-associated herpesvirus,KSHV)是卡波西肉瘤(Kaposi′s sarcoma,KS)等肿瘤的病因。一系列研究显示KSHV病毒基因与Notch信号通路分子的交互作用在调控KSHV复制以及促进肿瘤发生中发挥了重要作用。Notch信号传导通路由配体、受体、转录因子、效应分子等组成,相邻细胞间通过Notch信号调节细胞分化、增殖和凋亡、器官形成和形态发生等过程。本文就KSHV对Notch信号的调控以及Notch信号在KSHV复制及肿瘤形成中的作用作一综述。

Leech-Centipede Granules Suppress EndMT to Improve Erectile Dysfunction in Rats with Diabetes Mellitus via TGF-β/Smad Pathway

Objective:To investigate whether Leech-Centipede(LC) Granules can improve erectile function in rats with diabetes mellitus-associated erectile dysfunction(DMED) through endothelial-to-mesenchymal transition(EndMT) inhibition.Methods:Components of LC Granules were identified via ultra-high-performance liquid chromatography.Thirty male Sprague Dawley rats were injected with streptozotocin and fed continuously for 8weeks to establish the DMED rat model.Rats with erectile dysfunction symptoms diagnosed using apomorphine were divided into DMED and low-,medium-,and high-doses LC groups(n=6 in each).The negative control(NC, n=6) and DMED groups were given 5 mL of deionized water via intragastric gavage,and the low-,mediumand the high-doses LC groups were administered LC at 1.6,3.2,and 6.4 g/kg,respectively,via intragastric gavage for 4 weeks.The intracavernous pressure(ICP),mean arterial pressure(MAP),and nitric oxide(NO) levels in cavernous tissue were measured for each group.Quantitative reverse transcription-polymerase chain reaction and Western blot were used to detect mRNA and protein expressions of endothelial and mesenchymal markers.Immunofluorescence staining was used to observe α-SMA, and Masson’s trichrome staining was performed to determine the myofiber/collagen ratio.Results:A total of 474 active components were identified.After treatment,the ICP/MAP value and NO level were significantly higher in the medium-and high-dose LC groups than in the DMED group(P<0.05).Compared with the DMED groups,the medium-and high-dose groups LC significantly increased and decreased endothelial and mesenchymal markers expression,respectively(P<0.05).Tumor growth factor(TGF) β RⅡ,p-Smad2, and p-Smad3 levels were considerably higher following diabetes onset but reduced following LC intervention(P<0.05),except for TGF β 1(P>0.05).α-SMA expression was significantly higher in the DMED group and was reduced in all LC intervention groups(P>0.05).The myofiber/collagen ratio in the LC groups was higher than that in the DMED group but lower than that in the NC group(all P<0.05).Conclusions:LC Granules may improve the erectile function of DMED rats by suppressing TGF-β/Smad pathway to reverse EndMT.