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1.
J Environ Manage ; 354: 120445, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38412732

ABSTRACT

In this study, the effect of external agricultural phytohormones (mixed phytohormones) addition (1.0, 5.0, 10.0, and 20.0 mg L-1) on the growth performance, lipid productivity, and sedimentation efficiency of Chlorella pyrenoidosa cultivated in saline wastewater was investigated. Among the different concentrations evaluated, the highest biomass (1.00 g L-1) and lipid productivity (11.11 mg L-1 d-1) of microalgae were obtained at 10.0 mg L-1 agricultural phytohormones addition. Moreover, exogenous agricultural phytohormones also improved the sedimentation performance of C. pyrenoidosa, which was conducive to the harvest of microalgae resources, and the improvement of sedimentation performance was positively correlated with the amount of agricultural phytohormones used. The promotion of extracellular polymeric substances synthesis by phytohormones in microalgal cells could be considered as the reason for its promotion of microalgal sedimentation. Transcriptome analysis revealed that the addition of phytohormones upregulated the expression of genes related to the mitogen-activated protein kinase (MAPK)-mediated phytohormone signaling pathway and lipid synthesis, thereby improving salinity tolerance and lipid production in C. pyrenoidosa. Overall, agricultural phytohormones provide an effective and inexpensive strategy for increasing the lipid productivity and sedimentation efficiency of microalgae cultured in saline wastewater.


Subject(s)
Chlorella , Microalgae , Wastewater , Plant Growth Regulators , Lipids , Microalgae/metabolism , Biomass
2.
J Clin Invest ; 133(20)2023 10 16.
Article in English | MEDLINE | ID: mdl-37607001

ABSTRACT

Human cancers induce a chaotic, dysfunctional vasculature that promotes tumor growth and blunts most current therapies; however, the mechanisms underlying the induction of a dysfunctional vasculature have been unclear. Here, we show that split end (SPEN), a transcription repressor, coordinates rRNA synthesis in endothelial cells (ECs) and is required for physiological and tumor angiogenesis. SPEN deficiency attenuated EC proliferation and blunted retinal angiogenesis, which was attributed to p53 activation. Furthermore, SPEN knockdown activated p53 by upregulating noncoding promoter RNA (pRNA), which represses rRNA transcription and triggers p53-mediated nucleolar stress. In human cancer biopsies, a low endothelial SPEN level correlated with extended overall survival. In mice, endothelial SPEN deficiency compromised rRNA expression and repressed tumor growth and metastasis by normalizing tumor vessels, and this was abrogated by p53 haploinsufficiency. rRNA gene transcription is driven by RNA polymerase I (RNPI). We found that CX-5461, an RNPI inhibitor, recapitulated the effect of Spen ablation on tumor vessel normalization and combining CX-5461 with cisplatin substantially improved the efficacy of treating tumors in mice. Together, these results demonstrate that SPEN is required for angiogenesis by repressing pRNA to enable rRNA gene transcription and ribosomal biogenesis and that RNPI represents a target for tumor vessel normalization therapy of cancer.


Subject(s)
Neoplasms , Tumor Suppressor Protein p53 , Humans , Mice , Animals , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Endothelial Cells/metabolism , Transcription, Genetic , RNA Polymerase I/genetics , Neoplasms/genetics , DNA-Binding Proteins/genetics , RNA-Binding Proteins/genetics
3.
Bioresour Technol ; 367: 128270, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36347483

ABSTRACT

In this study, a novel method of coupling phytohormones with saline wastewater was proposed to drive efficient microalgal lipid production. All the six phytohormones effectively promoted microalgae growth in saline wastewater, and further increased the microalgal lipid content based on salt stress, so as to achieve a large increase in microalgal lipid productivity. Among the phytohormones used, abscisic acid had the most significant promoting effect. Under the synergistic effect of 20 g/L salt and 20 mg/L abscisic acid, the microalgal lipid productivity reached 3.7 times that of the control. Transcriptome analysis showed that differentially expressed genes (DEGs) of microalgae in saline wastewater were mainly up-regulated under the effects of phytohormones except brassinolide. Common DEGs analysis showed that phytohormones all regulated the expression of genes related to DNA repair and substance synthesis. In conclusion, synergistic effect of salt stress and phytohormones can greatly improve the microalgal lipid production efficiency.


Subject(s)
Microalgae , Microalgae/metabolism , Plant Growth Regulators , Wastewater , Abscisic Acid/metabolism , Lipids , Salt Stress , Biomass
4.
Neoplasma ; 69(5): 1185-1197, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36004647

ABSTRACT

EFEMP2 has been reported as a candidate oncogene. To investigate the role of EFEMP2 in cervical cancer cell proliferation and invasion, the mRNA and protein expressions of EFEMP2 in 5 different cervical cancer cell lines were detected. And then the effects of up- or down-regulation of EFEMP2 expression on the biological behavior of cervical cancer cells were further investigated by transfection experiments and cell function assays in vitro and in vivo. The results revealed that EFEMP2 was highly expressed in highly invasive Ca Ski cells and lowly expressed in less invasive HT-3 cells. When EFEMP2 was knocked down, the proliferation and invasion ability of cervical cancer cells were also reduced, accompanied by the decreased expression of MMP-1, MMP-13, MMP-3, and MMP-10, meanwhile, the EMT process was blocked and the Raf/MEK/ERK signaling pathway was inhibited. On the contrary, the upregulation of EFEMP2 could promote the proliferation and invasion of cervical cancer cells by inducing EMT and activating the Raf/MEK/ERK pathway. In conclusion, EFEMP2 could increase the invasion ability of cervical cancer cells by upregulating the expression of MMP-1, MMP-13, MMP-3, and MMP-10 and inducing the EMT process through the Raf/MEK/ERK pathway. EFEMP2 played a promoting role in the development of cervical cancer and provided a potential therapeutic target for inhibiting the invasion and metastasis of cancer cells and improving the prognosis of cervical cancer patients.


Subject(s)
MAP Kinase Signaling System , Uterine Cervical Neoplasms , Female , Humans , Cell Line, Tumor , Cell Movement , Cell Proliferation , MAP Kinase Signaling System/genetics , Matrix Metalloproteinase 1/genetics , Matrix Metalloproteinase 1/metabolism , Matrix Metalloproteinase 10/metabolism , Matrix Metalloproteinase 13/metabolism , Matrix Metalloproteinase 3/metabolism , Mitogen-Activated Protein Kinase Kinases , RNA, Messenger/metabolism , Signal Transduction , Uterine Cervical Neoplasms/genetics
5.
Mater Horiz ; 9(3): 1036-1044, 2022 Mar 07.
Article in English | MEDLINE | ID: mdl-35022629

ABSTRACT

Phase engineering of two-dimensional transition metal dichalcogenides has received increasing attention in recent years due to its atomically thin nature and polymorphism. Here, we first realize an electric-field-induced controllable phase transition between semiconducting 2H and metallic 1T' phases in MoTe2 memristive devices. The device performs stable bipolar resistive switching with a cycling endurance of over 105, an excellent retention characteristic of over 105 s at an elevated temperature of 85 °C and an ultrafast switching of ∼5 ns for SET and ∼10 ns for RESET. More importantly, the device works in different atmospheres including air, vacuum and oxygen, and even works with no degradation after being placed in air for one year, indicating excellent surrounding and time stability. In situ Raman analysis reveals that the stable resistive switching originates from a controllable phase transition between 2H and 1T' phases. Density functional theory calculations reveal that the Te vacancy facilitates the phase transition in MoTe2 through decreasing the barrier between 2H and 1T' phases, and serving as nucleation sites due to the elimination of repulsive forces. This electric-field-induced controllable phase transition in MoTe2 devices offers new opportunities for developing reliable and ultrafast phase transition devices based on atomically thin membranes.

6.
Bioresour Technol ; 347: 126392, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34822986

ABSTRACT

Saline wastewater was used in this study to culture freshwater microalgae Chlorella pyrenoidosa in sequencing batch photobioreactor to improve the sedimentation and lipid production of algal cells. Influent salinity of 0.5% or above effectively promoted the sedimentation of microalgae in the settling stage of photobioreactor, and greatly reduced the algal biomass in effluent. The mechanism of the saline wastewater in improving the sedimentation of microalgae included decreasing zeta potential, increasing cell particle size and promoting extracellular polymeric substances synthesis, which varied with influent salinity. Saline wastewater also promoted the lipid accumulation in microalgae. Lipid content of microalgae increased with increasing influent salinity. However, the growth of microalgae was greatly inhibited at the influent salinity of 2.0% and 3.0%. Therefore, the PBR with influent salinity of 1.0% achieved the highest productivity of microalgae lipid. The saturation of fatty acids of microalgae gradually increased with increasing influent salinity.


Subject(s)
Chlorella , Microalgae , Biomass , Fatty Acids , Photobioreactors , Wastewater
7.
Mol Ther Nucleic Acids ; 25: 554-566, 2021 Sep 03.
Article in English | MEDLINE | ID: mdl-34589277

ABSTRACT

After angiogenesis-activated embryonic and early postnatal vascularization, endothelial cells (ECs) in most tissues enter a quiescent state necessary for proper tissue perfusion and EC functions. Notch signaling is essential for maintaining EC quiescence, but the mechanisms of action remain elusive. Here, we show that microRNA-218 (miR-218) is a downstream effector of Notch in quiescent ECs. Notch activation upregulated, while Notch blockade downregulated, miR-218 and its host gene Slit2, likely via transactivation of the Slit2 promoter. Overexpressing miR-218 in human umbilical vein ECs (HUVECs) significantly repressed cell proliferation and sprouting in vitro. Transcriptomics showed that miR-218 overexpression attenuated the MYC proto-oncogene, bHLH transcription factor (MYC, also known as c-myc) signature. MYC overexpression rescued miR-218-mediated proliferation and sprouting defects in HUVECs. MYC was repressed by miR-218 via multiple mechanisms, including reduction of MYC mRNA, repression of MYC translation by targeting heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1), and promoting MYC degradation by targeting EYA3. Inhibition of miR-218 partially reversed Notch-induced repression of HUVEC proliferation and sprouting. In vivo, intravitreal injection of miR-218 reduced retinal EC proliferation accompanied by MYC repression, attenuated pathological choroidal neovascularization, and rescued retinal EC hyper-sprouting induced by Notch blockade. In summary, miR-218 mediates the effect of Notch activation of EC quiescence via MYC and is a potential treatment for angiogenesis-related diseases.

8.
Bioresour Technol ; 337: 125457, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34182348

ABSTRACT

This study investigated the possibility of coupling anaerobic hydrolysis in an anaerobic membrane bioreactor (AnMBR) with mixotrophic microalgae cultivation in a membrane photobioreactor (MPBR) for the sustainable treatment of municipal wastewater. Using the hydrolyzed wastewater discharged from AnMBR, Chlorella pyrenoidosa in MPBR grew in a mixotrophic mode and realized rapid growth. During the stable operation, MPBR achieved average carbon capture rate of 42.82 mg L-1 d-1 and algal lipid production rate of 19.66 mg L-1 d-1. The average reduction in TN, TP, and TOC during stable operation was 96.7%, 98.0%, and 95.9%, respectively. Mass balance analysis showed that the overall system captured 14.76 mg of carbon from the atmosphere per liter of wastewater treated. Therefore, this AnMBR-MPBR hybrid system simultaneously realized advanced treatment of municipal wastewater, efficient production of algal lipid, and carbon capture from atmosphere, and thus has a good potential in the sustainable treatment of municipal wastewater.


Subject(s)
Chlorella , Microalgae , Anaerobiosis , Biomass , Hydrolysis , Photobioreactors , Wastewater
9.
Front Oncol ; 10: 559057, 2020.
Article in English | MEDLINE | ID: mdl-33123470

ABSTRACT

Background: Salivary duct carcinoma (SDC), an aggressive and rare malignancy with poor prognosis, is mostly associated with the overexpression of the androgen receptor (AR) and human epidermal growth factor receptor 2 (HER2). However, limited data are available for the targeting of both HER2 and AR in advanced/metastatic SDC. Case Presentation: A 62-year-old man with advanced SDC accompanied by lung and lymph node metastasis showed disease progression after two lines of chemotherapy and endocrine therapy. Metastatic lesions from the lung biopsy were obtained, and immunohistochemistry (IHC) indicated the overexpression of AR and HER2 (3+). The patient was administered pyrotinib (a pan-ErbB receptor tyrosine kinase inhibitor) and bicalutamide (an androgen receptor antagonist) as a third-line treatment. During the ten months of follow-up, a durable partial response was achieved with this combination. Conclusions: This is the first clinical study to report the successful application of pyrotinib in a patient with advanced SDC. We recommend that pyrotinib and bicalutamide be used as salvage therapy for AR and HER2-positive advanced metastases in SDC, given the favorable response and clinical benefit.

10.
Sci Total Environ ; 725: 138524, 2020 Jul 10.
Article in English | MEDLINE | ID: mdl-32302854

ABSTRACT

Microalgae based wastewater treatment has attracted increasing attention for its many advantages in recent years. In this study, a novel microalgae biofilm membrane photobioreactor (BF-MPBR) was developed for the efficient microalgae cultivation and the removal of nutrient and sulfonamides (SAs) from marine aquaculture wastewater. Two BF-MPBRs with hydraulic retention time (HRT) of 1 day and 2 days respectively were continuously operated for 70 days without harvesting microalgae. Concentrated and attached culture of marine Chlorella vulgaris was achieved in these continuous flow BF-MPBRs due to the suspended solid carriers and microfiltration membrane module in the reactors. The algal biomass productivity achieved in BF-MPBRs with HRT of 1 day and 2 days were 14.02 and 22.03 mg L-1 day-1, respectively. In addition, at the end of the cultivation, 60.4% and 45.0% of microalgae were fixed into algal biofilm in BF-MPBRs with 1 day and 2 day HRT, respectively. Compared with batch cultivation, more efficient nutrient and SAs removal performance was achieved in BF-MPBRs, although the HRT of the BF-MPBRs used in this study was only 1 or 2 days. During the stable operation stage of the BF-MPBRs, the reduction in dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), sulfadiazine (SDZ), sulfamethazine (SMZ) and sulfamethoxazole (SMX) were found in the range of 91.0-99.6%, 92.1-98.4%, 61.0-79.2%, 50.0-76.7% and 60.8-82.1%, respectively. Therefore, nutrient and SAs were simultaneously and efficiently removed from marine aquaculture wastewater by microalgae cultivation in BF-MPBR.


Subject(s)
Chlorella vulgaris , Microalgae , Aquaculture , Biofilms , Biomass , Nitrogen/analysis , Nutrients , Phosphorus , Photobioreactors , Sulfonamides , Wastewater
11.
Biol Open ; 9(1)2020 01 24.
Article in English | MEDLINE | ID: mdl-31980423

ABSTRACT

In clinical practice, some breast cancer (BC) patients carry a rare ERBB2 in-frame insertion (p. Pro780_Tyr781insGlySerPro) and are resistant to anti-ERBB2 therapy. To explore the potential procarcinogenic role of this ERBB2 mutation, we conducted the present study using BC cells overexpressing wild-type (WT) ERBB2 or P780-Y781 ERBB2 [mutated (MT)]. MDA-MB-231 and MCF-7 cells were transfected with the following plasmids using a lentivirus system: negative control (ERBB2-NC), WT ERBB2 overexpression (ERBB2-WT), and P780-Y781 ERBB2 overexpression (ERBB2-MT). P780-Y781 ERBB2 conferred significant resistance to lapatinib, as assessed by cell viability and colony counts. Analysis of the cell cycle showed that the P780-Y781 ERBB2 group showed an elevated proportion of cells in S, G2, and M phases compared with WT ERBB2 when exposed to lapatinib. Following lapatinib treatment, phosphorylated AKT (p-AKT) was strongly upregulated in the P780-Y781 ERBB2 group. Among ERBB2+ patients, the P780-Y781 ERBB2 group showed increased levels of p-AKT. Furthermore, the AKT inhibitor perifosine effectively suppressed lapatinib resistance, as indicated by the lapatinib inhibition curve and results of the colony formation assay, and decreased AKT phosphorylation. Altogether, we discovered a procarcinogenic mutation of ERBB2 that enhances BC cell growth through AKT signaling and causes resistance to lapatinib. Patients with this in-frame insertion mutation of ERBB2 should be recommended other therapeutic strategies apart from ERBB2 tyrosine kinase inhibitors, in particular lapatinib.


Subject(s)
Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Drug Resistance, Neoplasm/genetics , Lapatinib/pharmacology , Mutagenesis, Insertional , Proto-Oncogene Proteins c-akt/metabolism , Receptor, ErbB-2/genetics , Alleles , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Apoptosis/genetics , Biomarkers, Tumor , Breast Neoplasms/diagnosis , Breast Neoplasms/drug therapy , Cell Cycle/genetics , Cell Line, Tumor , Female , Humans , Middle Aged , Protein Kinase Inhibitors/pharmacology , Receptor, ErbB-2/metabolism , Signal Transduction/drug effects , Tomography, X-Ray Computed , Treatment Outcome
12.
Angiogenesis ; 21(3): 635-652, 2018 08.
Article in English | MEDLINE | ID: mdl-29675549

ABSTRACT

Ocular neovascularization is a comprehensive process involved in retinal vascular development and several blinding diseases such as age-related macular degeneration and retinopathy of prematurity, with vascular endothelial growth factor (VEGF) regarded as the master regulator. However, the qualified effect of anti-VEGF therapy reveals that the underlying mechanisms are still not clearly identified. To initialize angiogenesis, endothelial cells undergo a phenotype switching to generate highly migratory and invasive cells. This process shares certain similar characters observed in endothelial-mesenchymal transition (EndMT). Here, we found that SNAI1, an EndMT transcription factor, was expressed by endothelial cells in both physiological and pathological ocular neovascularization. SNAI1 overexpression triggered cell morphological change and enhanced cell motility, while loss of SNAI1 attenuated migration, invasion and sprouting. RNA sequence analysis further revealed that SNAI1 knockdown decreased the expression of genes related to cytoskeleton rearrangement and ECM remodeling. Moreover, intravitreal injection of small interfering RNA of SNAI1 suppressed new vessel formation in developing retina as well as mice model of choroidal neovascularization and oxygen-induced retinopathy. Therefore, we propose that the EndMT transcription factor SNAI1 promotes the early phase of ocular neovascularization and may provide a potential therapeutic target.


Subject(s)
Neovascularization, Pathologic/physiopathology , Retina/physiopathology , Retinal Neovascularization/physiopathology , Retinal Vessels/physiopathology , Snail Family Transcription Factors/metabolism , Animals , Cell Movement/genetics , Cytoskeleton/genetics , Cytoskeleton/metabolism , Extracellular Matrix/genetics , Extracellular Matrix/metabolism , Gene Expression Regulation , Human Umbilical Vein Endothelial Cells/metabolism , Human Umbilical Vein Endothelial Cells/pathology , Humans , Male , Mice , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/metabolism , Neovascularization, Pathologic/pathology , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Retina/metabolism , Retina/pathology , Retinal Neovascularization/genetics , Retinal Neovascularization/pathology , Retinal Vessels/metabolism , Retinal Vessels/pathology , Sequence Analysis, RNA , Snail Family Transcription Factors/genetics
13.
Hepatology ; 68(2): 677-690, 2018 08.
Article in English | MEDLINE | ID: mdl-29420858

ABSTRACT

Liver sinusoidal endothelial cells (LSECs) critically regulate liver homeostasis and diseases through angiocrine factors. Notch is critical in endothelial cells (ECs). In the current study, Notch signaling was activated by inducible EC-specific expression of the Notch intracellular domain (NIC). We found that endothelial Notch activation damaged liver homeostasis. Notch activation resulted in decreased fenestration and increased basement membrane, and a gene expression profile with decreased LSEC-associated genes and increased continuous EC-associated genes, suggesting LSEC dedifferentiation. Consistently, endothelial Notch activation enhanced hepatic fibrosis (HF) induced by CCl4 . Notch activation attenuated endothelial nitric oxide synthase (eNOS)/soluble guanylate cyclase (sGC) signaling, and activation of sGC by 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole (YC-1) reversed the dedifferentiation phenotype. In addition, Notch activation subverted the hepatocyte-supporting angiocrine profile of LSECs by down-regulating critical hepatocyte mitogens, including Wnt2a, Wnt9b, and hepatocyte growth factor (HGF). This led to compromised hepatocyte proliferation under both quiescent and regenerating conditions. Whereas expression of Wnt2a and Wnt9b was dependent on eNOS-sGC signaling, HGF expression was not rescued by the sGC activator, suggesting heterogeneous mechanisms of LSECs to maintain hepatocyte homeostasis. CONCLUSION: Endothelial Notch activation results in LSEC dedifferentiation and accelerated liver fibrogenesis through eNOS-sGC signaling, and alters the angiocrine profile of LSECs to compromise hepatocyte proliferation and liver regeneration (LR). (Hepatology 2018).


Subject(s)
Endothelial Cells/metabolism , Hepatocytes/metabolism , Liver Cirrhosis/metabolism , Liver Regeneration/genetics , Receptors, Notch/metabolism , Animals , Blotting, Western , Cell Culture Techniques , Cell Proliferation , Endothelial Cells/pathology , Enzyme-Linked Immunosorbent Assay , Gene Expression Profiling , Liver/metabolism , Liver/pathology , Liver Regeneration/physiology , Male , Mice , Mice, Inbred C57BL , Real-Time Polymerase Chain Reaction , Signal Transduction/genetics
14.
Biochem Biophys Res Commun ; 483(1): 488-494, 2017 01 29.
Article in English | MEDLINE | ID: mdl-28007595

ABSTRACT

Although it has been suggested that Dll3, one of the Notch ligands, promotes the proliferation and inhibits the apoptosis of cancer cells, the role of Dll3 in cancers remains unclear. In this study, we found that in the murine Lewis lung carcinoma (LLC) cells, the level of Dll3 mRNA changed upon tumor microenvironment (TME) stimulation, namely, decreased under hypoxia or stimulated with tumor necrosis factor (TNF)-α. Dll3 was also expressed at higher level in human lung carcinoma tissues than in the para-carcinoma tissues. Overexpression of Dll3 in LLC cells promoted cell proliferation and reduced apoptosis in vitro, and enhanced tumor growth when inoculated in vivo in mice. The Dll3-mediated proliferation could be due to increased Akt phosphorylation in LLC cells, because an Akt inhibitor counteracted Dll3-induced proliferation. Moreover, Dll3 overexpression promoted PI3K/Akt signaling through inhibiting Notch signaling.


Subject(s)
Carcinoma, Lewis Lung/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Lung Neoplasms/metabolism , Membrane Proteins/metabolism , Receptors, Notch/metabolism , Animals , Carcinoma, Lewis Lung/pathology , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Cell Hypoxia , Cell Proliferation , Gene Expression Regulation, Neoplastic , Humans , Intracellular Signaling Peptides and Proteins/genetics , Lung Neoplasms/pathology , Membrane Proteins/genetics , Mice, Inbred C57BL , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Tumor Cells, Cultured , Tumor Microenvironment/drug effects , Tumor Necrosis Factor-alpha/pharmacology , Xenograft Model Antitumor Assays
15.
J Am Heart Assoc ; 5(2)2016 Feb 08.
Article in English | MEDLINE | ID: mdl-26857067

ABSTRACT

BACKGROUND: Endothelial cells (ECs) form blood vessels through angiogenesis that is regulated by coordination of vascular endothelial growth factor (VEGF), Notch, transforming growth factor ß, and other signals, but the detailed molecular mechanisms remain unclear. METHODS AND RESULTS: Small RNA sequencing initially identified miR-342-5p as a novel downstream molecule of Notch signaling in ECs. Reporter assay, quantitative reverse transcription polymerase chain reaction and Western blot analysis indicated that miR-342-5p targeted endoglin and modulated transforming growth factor ß signaling by repressing SMAD1/5 phosphorylation in ECs. Transfection of miR-342-5p inhibited EC proliferation and lumen formation and reduced angiogenesis in vitro and in vivo, as assayed by using a fibrin beads-based sprouting assay, mouse aortic ring culture, and intravitreal injection of miR-342-5p agomir in P3 pups. Moreover, miR-342-5p promoted the migration of ECs, accompanied by reduced endothelial markers and increased mesenchymal markers, indicative of increased endothelial-mesenchymal transition. Transfection of endoglin at least partially reversed endothelial-mesenchymal transition induced by miR-342-5p. The expression of miR-342-5p was upregulated by transforming growth factor ß, and inhibition of miR-342-5p attenuated the inhibitory effects of transforming growth factor ß on lumen formation and sprouting by ECs. In addition, VEGF repressed miR-342-5p expression, and transfection of miR-342-5p repressed VEGFR2 and VEGFR3 expression and VEGF-triggered Akt phosphorylation in ECs. miR-342-5p repressed angiogenesis in a laser-induced choroidal neovascularization model in mice, highlighting its clinical potential. CONCLUSIONS: miR-342-5p acts as a multifunctional angiogenic repressor mediating the effects and interaction among angiogenic pathways.


Subject(s)
Choroidal Neovascularization/metabolism , Human Umbilical Vein Endothelial Cells/drug effects , MicroRNAs/metabolism , Neovascularization, Physiologic/drug effects , Receptor, Notch1/metabolism , Transforming Growth Factor beta/pharmacology , Vascular Endothelial Growth Factor A/pharmacology , 3' Untranslated Regions , Animals , Binding Sites , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolism , Cell Movement/drug effects , Cell Proliferation/drug effects , Choroidal Neovascularization/genetics , Choroidal Neovascularization/pathology , Choroidal Neovascularization/prevention & control , Disease Models, Animal , Endoglin/genetics , Endoglin/metabolism , Epithelial-Mesenchymal Transition/drug effects , HeLa Cells , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Mice, Inbred BALB C , Mice, Transgenic , MicroRNAs/genetics , Phosphorylation , Proto-Oncogene Proteins c-akt , Receptor, Notch1/genetics , Signal Transduction/drug effects , Time Factors , Transfection , Transforming Growth Factor beta/metabolism , Vascular Endothelial Growth Factor A/metabolism
16.
Genet Mol Biol ; 37(3): 508-17, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25249773

ABSTRACT

Peptidoglycan recognition proteins (PGRPs) are innate immune molecules that have been structurally conserved throughout evolution in invertebrates and vertebrates. In this study, peptidoglycan recognition protein HcPGRP1 and its isoform HcPGRP1a were identified in the freshwater mussel Hyriopsis cumingii. The full-length cDNAs of HcPGRP1 (973 bp) and HcPGRP1a (537 bp) encoded polypeptides with 218 and 151 amino acids, respectively. Sequence analysis showed that HcPGRP1 had one C-terminal PGRP domain that was conserved throughout evolution. Phylogenetic analysis showed that HcPGRP1 clustered closely with EsPGRP4 of Euprymna scolopes. Real-time PCR showed that the mRNA transcripts of HcPGRP1 and HcPGRP1a were constitutively expressed in various tissues, with the highest level in hepatopancreas. Stimulation with lipopolysaccharide (LPS) and peptidoglycan (PGN) significantly up-regulated HcPGRP1 mRNA expression in hepatopancreas and foot, but not in gill, whereas HcPGRP1a expression was significantly up-regulated in all three tissues. Our results indicate that HcPGRP1 is both a constitutive and inducible protein that may be involved in immune responses (recognition and defense) against invaders.

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