Zinc Finger E-Box Binding Protein 2 (ZEB2) Suppress Apoptosis of Vascular Endothelial Cells Induced by High Glucose Through Mitogen-Activated Protein Kinases (MAPK) Pathway Activation

ZEB2 alleviates Hirschsprung's-associated enterocolitis by promoting the proliferation and differentiation of enteric neural precursor cells via the Notch-1/Jagged-2 pathway

BACKGROUND

Hirschsprung's-associated enterocolitis (HAEC) is a prevalent complication of Hirschsprung's disease (HSCR). Zinc finger E-box binding homeobox 2 (ZEB2) and Notch-1/Jagged-2 are dysregulated in HSCR, but their role in HAEC progression remains poorly understood. We aimed to explore the role and underlying mechanism of enteric neural precursor cells (ENPCs) and the ZEB2/Notch-1/Jagged-2 pathway in HAEC development.

METHODS

Colon tissues were collected from HSCR and HAEC patients. ENPCs were isolated from the HAEC group and stimulated by lipopolysaccharide (LPS). The expressions of ZEB2/Notch-1/Jagged-2 were measured using RT-qPCR and Western blot. Immunofluorescence and cell counting kit-8 assays were performed to assess the differentiation and proliferation of ENPCs. Inflammatory factors were measured by ELISA kits. Co-immunoprecipitation and bioinformatic analysis were used to explore the interaction between ZEB2 and Notch-1. Small interfering RNA and overexpression vectors were used to investigate the role and mechanism of ZEB2 and Notch-1 in regulating ENPCs' proliferation and differentiation during HAEC progression.

RESULTS

We observed increased LPS in the colon tissues of HAEC, with downregulated ZEB2 expression and upregulated Notch-1/Jagged-2 expression. ZEB2 interacts with Notch-1. LPS treatment downregulated ZEB2 expression, upregulated Notch-1/Jagged-2 expression, and induced proliferation and differentiation disorders in ENPCs, which were reversed by the knockdown of Notch-1. Furthermore, overexpression of ZEB2 inhibited Notch-1/Jagged-2 signaling and ameliorated inflammation and dysfunction in LPS-induced ENPCs. Notch-1 overexpression enhanced LPS-induced dysfunction, but this effect was antagonized by the overexpression of ZEB2.

CONCLUSION

Overexpression of ZEB2 ameliorates LPS-induced ENPCs' dysfunction via the Notch-1/Jagged-2 pathway, thus playing a role in HAEC.

miR-141-3p protects against blood-brain barrier disruption and brain injury after intracerebral hemorrhage by targeting ZEB2

MicroRNAs (miRNAs) participate in the diagnosis and treatment of intracerebral hemorrhage (ICH). miR-141-3p has been widely reported to regulate neurological disorders and cerebropathy. However, the specific role of miR-141-3p in ICH has not yet been revealed. The aim of this study was exploration of the biological functions and mechanism of miR-141-3p in ICH by establishing a collagenase-induced ICH mouse model. After ICH induction, miR-141-3p mimics or miR-NC were administered into the right striatum of the model mice followed by the performance of neurological tests. After euthanasia of the mice, the injury volume, brain water content, and injury to the blood-brain barrier (BBB) were evaluated. Evans blue (EB) was used to stain the brain slices, and EB extravasation was detected to evaluate the injury to BBB. miR-141-3p expression in perihematomal edema and hematoma areas after ICH was assessed by RT-qPCR. The levels of tight junction proteins in brain tissues and human brain microvascular endothelial cells (BMECs) were evaluated by western blotting. The FITC-dextran 20 method was used to assess BMEC permeability. The binding between miR-141-3p and zinc finger E-box-binding homeobox 2 (ZEB2) was verified with a luciferase reporter assay. In this study, miR-141-3p overexpression alleviated ICH-induced brain injury and protected BBB integrity in vivo. ZEB2 was a target gene of miR-141-3p. ZEB2 overexpression promoted BBB disruption, and miR-141-3p overexpression attenuated the promoting effect exerted by ZEB2. Overall, miR-141-3p protects against BBB disruption and attenuates brain injuries induced by ICH by targeting ZEB2.

ZEB2, interacting with MDM2, contributes to the dysfuntion of brain microvascular endothelial cells and brain injury after intracerebral hemorrhage

ZEB2 has been shown to be upregulated in the brain tissues of rats with intracerebral hemorrhage (ICH), but its role in ICH-caused brain injury remains unclear. Here, an ICH rat model was established via intracerebral injection of autologous blood, and the lentivirus-mediated ZEB2 short hairpin RNA (sh-ZEB2) or negative control (scramble) were administered 0.5 hours after ICH. Silencing ZEB2 alleviated ICH-induced neurologic deficits and the increase of BBB permeability, brain water content and ZEB2 expression. Next, OGD (oxygen glucose deprivation) plus hemin was used to treat primary brain microvascular endothelial cells (BMECs) to simulate the ICH condition in vitro. OGD plus hemin upregulated ZEB2 expression and apoptosis, but reduced cell viability, migration, TEER (transendothelial electric resistance) and the expression of vascular-endothelial (VE-) cadherin, occludin and claudin-5, which was reversed by inhibiting ZEB2. Mechanism researches showed that ZEB2 interacted with MDM2 to up-regulate MDM2 protein expression, and then increased E2F1 protein level by suppressing its ubiquitination, which in turn promoted the transcription of ZEB2 to induce its protein expression, so as to enhance the interaction between ZEB2 and MDM2, thereby contributing to OGD plus hemin-induced endothelial dysfunction. Additionally, the joint interference of ZEB2 and MDM2 in vivo had better mitigative effects on ICH-induced brain injury compared with silencing ZEB2 alone. In summary, ZEB2 interacted with MDM2 to promote BMEC dysfunction and brain damage after ICH.

Endothelial Zeb2 preserves the hepatic angioarchitecture and protects against liver fibrosis

Aims

Hepatic capillaries are lined with specialized liver sinusoidal endothelial cells (LSECs) which support macromolecule passage to hepatocytes and prevent fibrosis by keeping hepatic stellate cells (HSCs) quiescent. LSEC specialization is co-determined by transcription factors. The zinc-finger E-box-binding homeobox (Zeb)2 transcription factor is enriched in LSECs. Here, we aimed to elucidate the endothelium-specific role of Zeb2 during maintenance of the liver and in liver fibrosis.

Methods and results

To study the role of Zeb2 in liver endothelium we generated EC-specific Zeb2 knock-out (EC^KO) mice. Sequencing of liver EC RNA revealed that deficiency of Zeb2 results in prominent expression changes in angiogenesis-related genes. Accordingly, the vascular area was expanded and the presence of pillars inside EC^KO liver vessels indicated that this was likely due to increased intussusceptive angiogenesis. LSEC marker expression was not profoundly affected and fenestrations were preserved upon Zeb2 deficiency. However, an increase in continuous EC markers suggested that Zeb2-deficient LSECs are more prone to dedifferentiation, a process called ‘capillarization’. Changes in the endothelial expression of ligands that may be involved in HSC quiescence together with significant changes in the expression profile of HSCs showed that Zeb2 regulates LSEC–HSC communication and HSC activation. Accordingly, upon exposure to the hepatotoxin carbon tetrachloride (CCl₄), livers of EC^KO mice showed increased capillarization, HSC activation, and fibrosis compared to livers from wild-type littermates. The vascular maintenance and anti-fibrotic role of endothelial Zeb2 was confirmed in mice with EC-specific overexpression of Zeb2, as the latter resulted in reduced vascularity and attenuated CCl₄-induced liver fibrosis.

Conclusion

Endothelial Zeb2 preserves liver angioarchitecture and protects against liver fibrosis. Zeb2 and Zeb2-dependent genes in liver ECs may be exploited to design novel therapeutic strategies to attenuate hepatic fibrosis.

Paeonol derivative-6 attenuates inflammation by activating ZEB2 in acute liver injury

Paeonol is a natural phenolic compound and isolated as an active ingredient from Moutan Cortex. Paeonol derivative-6 (DPF-6) is a derivative of paeonol improved in water solubility and bioavailability. Previous studies have reported that paeonol possesses a variety of pharmacological activities, such as antioxidant and anti-inflammatory properties. Moreover, we have previously verified that DPF-6 has anti-inflammatory effects. However, the role and fundamental mechanism of DPF-6 in acute liver injury (ALI) was still unclear. In this study, we indicated that DPF-6 inhibited inflammation and the expression of TNF-α, IL-6 and IL-1β in liver tissues and LPS-mediated L-02 cells, concomitant with the upregulated expression of ZEB2. More importantly, it was demonstrated that overexpression of ZEB2 inhibited the expression level of TNF-α, IL-6 and IL-1β in LPS-mediated L-02 cells. In contrast, knockdown of ZEB2 increased the expression level of TNF-α, IL-6 and IL-1β in LPS-mediated L-02 cells. Further studies showed that ZEB2 inhibited the inflammation cytokine secretion via JNK signaling pathway in L-02 cells. Taken together, all the above results indicate that DPF-6 increased the expression of ZEB2, consequently inhibited inflammation cytokine secretion through JNK signaling pathway, which may be utilized as a potential anti-inflammation monomeric compound in the treatment of ALI.

The effects of YKL-40 on angiogenic potential of HUVECs are partly mediated by syndecan-4

Background: YKL-40, a secreted glycoprotein, has a role in promoting tumor angiogenesis through syndecan-1 receptor. Syndecan-4 is a member of syndecan family. However, the effects of YKL-40 on migration and tube formation of human umbilical vein cells (HUVECs) mediated by syndecan-4 receptor are unknown. Materials and methods: HUVECs were transfected with lentivirus encoding syndecan-4 short hairpin (sh) RNAs (lenti-synd4 shRNAs) and the efficiency of transfection was measured using qRT-PCR and western blotting. The effects of recombinant protein of YKL-40 on migration and angiogenesis of HUVECs adjusted by syndecan-4 were determined by wound healing and tube formation assay. The expressions of protein kinase Cα (PKCα) and extracellular signal regulated kinases (ERKs) 1 and 2 (ERK1/2) in HUVECs were measured using western blotting. Results: The mRNA and protein expression of syndecan-4 were significantly decreased in HUVECs successfully transfected with lenti-synd4 shRNAs. Lenti-synd4 shRNAs remarkably inhibited the migration and tube formation of HUVECs stimulated by recombinant protein of YKL-40. The levels of PKCα and ratio of p-ERK1/2 to ERK1/2 in HUVECs were also decreased by down-regulating syndecan-4. Conclusion: The effects of YKL-40 on migration and tube formation of HUVECs are partly inhibited by knock-downing syndecan-4 through suppressing PKCα and ERK1/2 signaling pathways.

Unraveling the transcriptional determinants of liver sinusoidal endothelial cell specialization

Liver sinusoidal endothelial cells (LSECs) are the first liver cells to encounter waste macromolecules, pathogens, and toxins in blood. LSECs are highly specialized to mediate the clearance of these substances via endocytic scavenger receptors and are equipped with fenestrae that mediate the passage of macromolecules toward hepatocytes. Although some transcription factors (TFs) are known to play a role in LSEC specialization, information about the specialized LSEC signature and its transcriptional determinants remains incomplete.Based on a comparison of liver, heart, and brain endothelial cells (ECs), we established a 30-gene LSEC signature comprising both established and newly identified markers, including 7 genes encoding TFs. To evaluate the LSEC TF regulatory network, we artificially increased the expression of the 7 LSEC-specific TFs in human umbilical vein ECs. Although Zinc finger E-box-binding protein 2, homeobox B5, Cut-like homolog 2, and transcription factor EC (TCFEC) had limited contributions, musculoaponeurotic fibrosarcoma (C-MAF), GATA binding protein 4 (GATA4), and MEIS homeobox 2 (MEIS2) emerged as stronger inducers of LSEC marker expression. Furthermore, a combination of C-MAF, GATA4, and MEIS2 showed a synergistic effect on the increase of LSEC signature genes, including liver/lymph node-specific ICAM-3 grabbing non-integrin (L-SIGN) (or C-type lectin domain family member M (CLEC4M)), mannose receptor C-Type 1 (MRC1), legumain (LGMN), G protein-coupled receptor 182 (GPR182), Plexin C1 (PLXNC1), and solute carrier organic anion transporter family member 2A1 (SLCO2A1). Accordingly, L-SIGN, MRC1, pro-LGMN, GPR182, PLXNC1, and SLCO2A1 protein levels were elevated by this combined overexpression. Although receptor-mediated endocytosis was not significantly induced by the triple TF combination, it enhanced binding to E2, the hepatitis C virus host-binding protein. We conclude that C-MAF, GATA4, and MEIS2 are important transcriptional regulators of the unique LSEC fingerprint and LSEC interaction with viruses. Additional factors are however required to fully recapitulate the molecular, morphological, and functional LSEC fingerprint.NEW & NOTEWORTHY Liver sinusoidal endothelial cells (LSECs) are the first liver cells to encounter waste macromolecules, pathogens, and toxins in the blood and are highly specialized. Although some transcription factors are known to play a role in LSEC specialization, information about the specialized LSEC signature and its transcriptional determinants remains incomplete. Here, we show that Musculoaponeurotic Fibrosarcoma (C-MAF), GATA binding protein 4 (GATA4), and Meis homeobox 2 (MEIS2) are important transcriptional regulators of the unique LSEC signature and that they affect the interaction of LSECs with viruses.

Long non-coding RNA ZEB2-AS1 promotes the proliferation, metastasis and epithelial mesenchymal transition in triple-negative breast cancer by epigenetically activating ZEB2

The triple‐negative breast cancer is the most malignant type of breast cancer. Its pathogenesis and prognosis remain poor despite the significant advances in breast cancer diagnosis and therapy. Meanwhile, long noncoding RNAs (LncRNAs) play a pivotal role in the progression of malignant tumors. In this study, we found that LncRNA‐ZEB2‐AS1 was dramatically up‐regulated in our breast cancer specimens and cells (MDA231), especially in metastatic tumor specimens and highly invasive cells, and high lncRNA‐ZEB2‐AS1 expression is associated with clinicopathologic features and short survival of breast cancer patients. LncRNA‐ZEB2‐AS1 promotes the proliferation and metastasis of MDA231 cells in SCID mice. Thus, it is regarded as an oncogene in triple‐negative breast cancer. It is mainly endo‐nuclear and situated near ZEB2, positively regulating ZEB2 expression and activating the epithelial mesenchymal transition via the PI3K/Akt/GSK3β/Zeb2 signaling pathway. Meanwhile, EGF‐induced F‐actin polymerization in MDA231 cells can be suppressed by reducing lncRNA‐ZEB2‐AS1 expression. The migration and invasion of triple‐negative breast cancer can be altered through cytoskeleton rearrangement. In summary, we demonstrated that lncRNA‐ZEB2‐AS1 is an important factor affecting the development of triple‐negative breast cancer and thus a potential oncogene target.

Forkhead box M1 inhibits endothelial cell apoptosis and cell-cycle arrest through ROS generation

BACKGROUND

Hyperglycemia, a characteristic feature of diabetes, induces vascular complications by accelerating endothelial cell (EC) apoptosis and limiting their proliferation. The potential role of Forkhead box M1 (FoxM1) in high glucose (HG)-induced EC injury remains largely unknown. We aimed to investigate the role and underlying mechanism of FoxM1 in regulating EC injury.

MATERIAL AND METHODS

Human umbilical vein endothelial cells (HUVECs) were treated with various concentrations of glucose (5.5, 15, 30 and 50 mM). The expression of FoxM1 was determined via qPCR and western blotting. Overexpression of FoxM1 was achieved by transfection with FoxM1 overexpression plasmid. Reactive oxygen species (ROS) production, cell apoptotic rates, and cell cycle analysis were detected by flow cytometry, and cell proliferation was measured by CCK8 assay.

RESULTS

The expression level of FoxM1 was downregulated in HUVECs under HG condition when compared to cells with normal glucose. HG treatment induced overproduction of ROS and subsequent apoptosis. However, FoxM1 overexpression of FoxM1 reduced the levels of ROS and inhibited apoptosis. In addition, HG induced impairment of cell proliferation and caused cell cycle arrest in the G0/G1 phrase. Contrarily, FoxM1 overexpression promoted cell proliferation and alleviated G0/G1 cell cycle arrest caused by HG stimulation. Moreover, treatment with HG reduced phosphorylation of the Akt and ERK signaling pathways, and this was remarkably reversed by FoxM1 overexpression.

CONCLUSION

FoxM1 protects ECs from HG-induced growth arrest and cell apoptosis by suppressing ROS caused by the regulation of Akt and ERK pathways, which can aid in developing new therapeutic strategies for the treatment of EC dysfunction.

Reprogramming Bone Marrow Stem Cells to Functional Endothelial Cells in a Mini Pig Animal Model

Background

The aims of this study were to compare the morphological, biochemical, and functional properties of reprogrammed bone marrow stem cell (BMSC)-derived arterial endothelial cells (AECs) and venous endothelial cells (VECs), following adenosine triphosphate (ATP)-stimulation in a mini pig animal model.

Material/Methods

Bone marrow aspiration was performed in six adult mini pigs. Harvested mononuclear cells were isolated, cultured, and treated with vascular endothelial growth factor (VEGF) (16 μg/ml). Transformed cells were characterized using immunofluorescence staining for CD31 and von Willebrandt factor (vWF) and expression of endothelial nitric oxide synthase (eNOS). Cell release of nitric oxide (cNO) was measured using spectrophotometry. Matrigel assays were used to investigate angiogenesis in transformed BMSCs.

Results

Reprogrammed BMSCs in culture showed a typical cobblestone-like pattern of growth. Immunofluorescence staining was positive for CD31 and vWF expression. Expression of eNOS, using immunofluorescence staining and Western blot, showed no difference between the reprogrammed BMSCs and VECs. Spectrophotometric examination following stimulation with 10mmol/l ATP, showed comparable cNO release for reprogrammed BMSCs (10.87±1.76 pmol/10⁶ cells/min) and VECs (13.23±2.16 pmol/10⁶ cells/min), but reduced cNO release for AECS (3.44±0.75 pmol/10⁶ cells/min). Matrigel assay for angiogenesis showed vascular tube formation of differentiated BMSC endothelial cells (grade 3.25). BMSCs cultured without VEGF did not demonstrate vascular tube formation.

Conclusions

The findings of this study showed that eNOS expression and release of NO could be used to show that BMSCs can be reprogrammed to functional VECs and AECs.