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Circulation Research Oct 2020POSTN (Periostin) is an ECM (extracellular matrix) protein involved in tissue remodeling in response to injury and a contributing factor in tumorigenesis, suggesting...
RATIONALE
POSTN (Periostin) is an ECM (extracellular matrix) protein involved in tissue remodeling in response to injury and a contributing factor in tumorigenesis, suggesting that POSTN plays a role in the pathogenesis of pulmonary hypertension (PH).
OBJECTIVE
We aimed to gain insight into the mechanistic contribution of POSTN in experimental mouse models of PH and correlate these findings with PH in humans.
METHODS AND RESULTS
We used genetic epistasis approaches in human pulmonary artery endothelial cells (hPAECs), human pulmonary artery smooth muscle cells, and experimental mouse models of PH (Sugen 5416/hypoxia or chronic hypoxia) to discern the role of POSTN and its relationship to HIF (hypoxia-inducible factor)-1α signaling. We found that POSTN expression was correlated with the extent of PH in mouse models and in humans. Decreasing POSTN improved hemodynamic and cardiac responses in PH mice, blunted the release of growth factors and HIF-1α, and reversed the downregulated BMPR (bone morphogenetic protein receptor)-2 expression in hPAECs from patients with PH, whereas increasing POSTIN had the opposite effects and induced a hyperproliferative and promigratory phenotype in both hPAECs and human pulmonary artery smooth muscle cells. Overexpression of POSTN-induced activation of HIFs and increased the production of ET (endothelin)-1 and VEGF (vascular endothelial growth factor) in hPAECs. SiRNA-mediated knockdown of HIF-1α abolished the proangiogenic effect of POSTN. Blockade of TrkB (tyrosine kinase receptor B) attenuated the effect of POSTN on HIF-1α expression, while inhibition of HIF-1α reduced the expression of POSTN and TrkB. These results suggest that hPAECs produce POSTN via a HIF-1α-dependent mechanism.
CONCLUSIONS
Our study reveals that POSTN expression is increased in human and animal models of PH and fosters PH development via a positive feedback loop between HIF-1α and POSTN during hypoxia. We propose that manipulating POSTIN expression may be an efficacious therapeutic target in the treatment of PH. Our results also suggest that POSTN may serve as a biomarker to estimate the severity of PH.
Topics: Animals; Biomarkers; Bone Morphogenetic Protein Receptors, Type II; Cell Adhesion Molecules; Cell Hypoxia; Cell Movement; Cell Proliferation; Disease Models, Animal; Endothelial Cells; Endothelin-1; Humans; Hypertension, Pulmonary; Hypoxia-Inducible Factor 1, alpha Subunit; Indoles; Membrane Glycoproteins; Mice; Myocytes, Smooth Muscle; Protein-Tyrosine Kinases; Pulmonary Artery; Pyrroles; Receptor, trkB; Vascular Endothelial Growth Factor A
PubMed: 32752980
DOI: 10.1161/CIRCRESAHA.120.316943 -
American Journal of Physiology. Cell... Dec 2021Piezo is a mechanosensitive cation channel responsible for stretch-mediated Ca and Na influx in multiple types of cells. Little is known about the functional role of...
Piezo is a mechanosensitive cation channel responsible for stretch-mediated Ca and Na influx in multiple types of cells. Little is known about the functional role of Piezo1 in the lung vasculature and its potential pathogenic role in pulmonary arterial hypertension (PAH). Pulmonary arterial endothelial cells (PAECs) are constantly under mechanic stretch and shear stress that are sufficient to activate Piezo channels. Here, we report that Piezo1 is significantly upregulated in PAECs from patients with idiopathic PAH and animals with experimental pulmonary hypertension (PH) compared with normal controls. Membrane stretch by decreasing extracellular osmotic pressure or by cyclic stretch (18% CS) increases Ca-dependent phosphorylation (p) of AKT and ERK, and subsequently upregulates expression of Notch ligands, Jagged1/2 (Jag-1 and Jag-2), and Delta like-4 (DLL4) in PAECs. siRNA-mediated downregulation of Piezo1 significantly inhibited the stretch-mediated pAKT increase and Jag-1 upregulation, whereas downregulation of AKT by siRNA markedly attenuated the stretch-mediated Jag-1 upregulation in human PAECs. Furthermore, the mRNA and protein expression level of Piezo1 in the isolated pulmonary artery, which mainly contains pulmonary arterial smooth muscle cells (PASMCs), from animals with severe PH was also significantly higher than that from control animals. Intraperitoneal injection of a Piezo1 channel blocker, GsMTx4, ameliorated experimental PH in mice. Taken together, our study suggests that membrane stretch-mediated Ca influx through Piezo1 is an important trigger for pAKT-mediated upregulation of Jag-1 in PAECs. Upregulation of the mechanosensitive channel Piezo1 and the resultant increase in the Notch ligands (Jag-1/2 and DLL4) in PAECs may play a critical pathogenic role in the development of pulmonary vascular remodeling in PAH and PH.
Topics: Adult; Aged; Animals; Cells, Cultured; Endothelial Cells; Female; Humans; Hypertension, Pulmonary; Indoles; Ion Channels; Male; Mechanotransduction, Cellular; Mice; Mice, Inbred C57BL; Middle Aged; Pulmonary Artery; Pyrroles; Rats; Rats, Sprague-Dawley; Up-Regulation
PubMed: 34669509
DOI: 10.1152/ajpcell.00147.2021 -
British Journal of Cancer May 2008Metronomic chemotherapy refers to the administration of chemotherapy at low, nontoxic doses on a frequent schedule with no prolonged breaks. The aim of the study is to...
Metronomic chemotherapy refers to the administration of chemotherapy at low, nontoxic doses on a frequent schedule with no prolonged breaks. The aim of the study is to rationally develop a CPT-11 metronomic regimen in preclinical settings of colon cancer. In vitro cell proliferation, apoptosis and thrombospondin-1/vascular endothelial growth factor (TSP-1/VEGF) expression analyses were performed on endothelial (HUVEC, HMVEC-d) and colorectal cancer (HT-29, SW620) cells exposed for 144 h to metronomic concentrations of SN-38, the active metabolite of CPT-11. HT-29 human colorectal cancer xenograft model was used, and tumour growth, microvessel density and VEGF/TSP-1 quantification was performed in tumours. In vitro and in vivo combination studies with the tyrosine inhibitor semaxinib were also performed. SN-38 preferentially inhibited endothelial cell proliferation alone and interacted synergistically with semaxinib; it induced apoptosis and increased the expression and secretion of TSP-1. Metronomic CPT-11 alone and combined with semaxinib significantly inhibits tumour growth in the absence of toxicity, which was accompanied by decreases in microvessel density and increases in TSP-1 gene expression in tumour tissues. In vitro results show the antiangiogenic properties of low-concentration SN-38, suggesting a key role of TSP-1 in this effect. In vivo, the CPT-11 metronomic schedule is effective against tumour and microvessel growth without toxic effect on mice.
Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Agents, Phytogenic; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Camptothecin; Cell Proliferation; Colorectal Neoplasms; Enzyme-Linked Immunosorbent Assay; Gene Expression Regulation, Neoplastic; HT29 Cells; Humans; Immunoenzyme Techniques; Immunohistochemistry; Indoles; Irinotecan; Male; Mice; Mice, Nude; Microcirculation; Pyrroles; Thrombospondin 1; Transplantation, Heterologous; Vascular Endothelial Growth Factor A
PubMed: 18443598
DOI: 10.1038/sj.bjc.6604352 -
The American Journal of Pathology Jun 2019As time progresses, our understanding of disease pathology is propelled forward by technological advancements. Much of the advancements that aid in understanding disease... (Review)
Review
As time progresses, our understanding of disease pathology is propelled forward by technological advancements. Much of the advancements that aid in understanding disease mechanics are based on animal studies. Unfortunately, animal models often fail to recapitulate the entirety of the human disease. This is especially true with animal models used to study pulmonary arterial hypertension (PAH), a disease with two distinct phases. The first phase is defined by nonspecific medial and adventitial thickening of the pulmonary artery and is commonly reproduced in animal models, including the classic models (ie, hypoxia-induced pulmonary hypertension and monocrotaline lung injury model). However, many animal models, including the classic models, fail to capture the progressive, or second, phase of PAH. This is a stage defined by plexogenic arteriopathy, resulting in obliteration and occlusion of the small- to mid-sized pulmonary vessels. Each of these two phases results in severe pulmonary hypertension that directly leads to right ventricular hypertrophy, decompensated right-sided heart failure, and death. Fortunately, newly developed animal models have begun to address the second, more severe, side of PAH and aid in our ability to develop new therapeutics. Moreover, p38 mitogen-activated protein kinase activation emerges as a central molecular mediator of plexiform lesions in both experimental models and human disease. Therefore, this review will focus on plexiform arteriopathy in experimental animal models of PAH.
Topics: Animals; Disease Models, Animal; Disease Progression; Humans; Hypoxia; Indoles; MAP Kinase Signaling System; Mice; Mice, Knockout; Pulmonary Arterial Hypertension; Pulmonary Artery; Pyrroles; Rats
PubMed: 30926336
DOI: 10.1016/j.ajpath.2019.02.005 -
Circulation. Heart Failure Feb 2021Right ventricular (RV) dysfunction is a significant prognostic determinant of morbidity and mortality in pulmonary arterial hypertension (PAH). Despite the importance of...
Transcriptomic Analysis of Right Ventricular Remodeling in Two Rat Models of Pulmonary Hypertension: Identification and Validation of Epithelial-to-Mesenchymal Transition in Human Right Ventricular Failure.
BACKGROUND
Right ventricular (RV) dysfunction is a significant prognostic determinant of morbidity and mortality in pulmonary arterial hypertension (PAH). Despite the importance of RV function in PAH, the underlying molecular mechanisms of RV dysfunction secondary to PAH remain unclear. We aim to identify and compare molecular determinants of RV failure using RNA sequencing of RV tissue from 2 clinically relevant animal models of PAH.
METHODS
We performed RNA sequencing on RV from rats treated with monocrotaline or Sugen with hypoxia/normoxia. PAH and RV failure were confirmed by catheterization and echocardiography. We validated the RV transcriptome results using quantitative real-time polymerase chain reaction, immunofluorescence, and Western blot. Immunohistochemistry and immunofluorescence were performed on human RV tissue from control (n=3) and PAH-induced RV failure patients (n=5).
RESULTS
We identified similar transcriptomic profiles of RV from monocrotaline- and Sugen with hypoxia-induced RV failure. Pathway analysis showed genes enriched in epithelial-to-mesenchymal transition, inflammation, and metabolism. Histological staining of human RV tissue from patients with RV failure secondary to PAH revealed significant RV fibrosis and endothelial-to-mesenchymal transition, as well as elevated cellular communication network factor 2 (top gene implicated in epithelial-to-mesenchymal transition/endothelial-to-mesenchymal transition) expression in perivascular areas compared with normal RV.
CONCLUSIONS
Transcriptomic signature of RV failure in monocrotaline and Sugen with hypoxia models showed similar gene expressions and biological pathways. We provide translational relevance of this transcriptomic signature using RV from patients with PAH to demonstrate evidence of epithelial-to-mesenchymal transition/endothelial-to-mesenchymal transition and protein expression of cellular communication network factor 2 (CTGF [connective tissue growth factor]). Targeting specific molecular mechanisms responsible for RV failure in monocrotaline and Sugen with hypoxia models may identify novel therapeutic strategies for PAH-associated RV failure.
Topics: Aged; Aged, 80 and over; Angiogenesis Inhibitors; Animals; Disease Models, Animal; Epithelial-Mesenchymal Transition; Female; Gene Expression Profiling; Heart Failure; Heart Ventricles; Humans; Hypoxia; Indoles; Male; Middle Aged; Monocrotaline; Pulmonary Arterial Hypertension; Pyrroles; RNA-Seq; Rats; Real-Time Polymerase Chain Reaction; Transcriptome; Ventricular Dysfunction, Right; Ventricular Remodeling
PubMed: 33541093
DOI: 10.1161/CIRCHEARTFAILURE.120.007058 -
Frontiers in Immunology 2021Pulmonary arterial hypertension (PAH) is a chronic, incurable condition characterized by pulmonary vascular remodeling, perivascular inflammation, and right heart... (Review)
Review
Pulmonary arterial hypertension (PAH) is a chronic, incurable condition characterized by pulmonary vascular remodeling, perivascular inflammation, and right heart failure. Regulatory T cells (Tregs) stave off autoimmunity, and there is increasing evidence for their compromised activity in the inflammatory milieu of PAH. Abnormal Treg function is strongly correlated with a predisposition to PAH in animals and patients. Athymic Treg-depleted rats treated with SU5416, an agent causing pulmonary vascular injury, develop PAH, which is prevented by infusing missing CD4CD25FOXP3 Tregs. Abnormal Treg activity may also explain why PAH disproportionately affects women more than men. This mini review focuses on the role of Tregs in PAH with a special view to sexual dimorphism and the future promise of Treg therapy.
Topics: Animals; Autoimmunity; Endothelium, Vascular; Humans; Indoles; Pulmonary Arterial Hypertension; Pyrroles; Rats; Sex Characteristics; T-Lymphocytes, Regulatory; Vascular System Injuries
PubMed: 34489935
DOI: 10.3389/fimmu.2021.684657 -
Stem Cell Research & Therapy Nov 2023Kidney organoids derived from human pluripotent stem cells (HiPSCs) hold huge applications for drug screening, disease modeling, and cell transplanting therapy. However,...
BACKGROUND
Kidney organoids derived from human pluripotent stem cells (HiPSCs) hold huge applications for drug screening, disease modeling, and cell transplanting therapy. However, these applications are limited since kidney organoid cannot maintain complete morphology and function like human kidney. Kidney organoids are not well differentiated since the core of the organoid lacked oxygen, nutrition, and vasculature, which creates essential niches. Hypoxia-inducible factor-1 α (HIF-1α) serves as a critical regulator in vascularization and cell survival under hypoxia environment. Less is known about the role of HIF-1α in kidney organoids in this regard. This study tried to investigate the effect of HIF-1α in kidney organoid vascularization and related disease modeling.
METHODS
For the vascularization study, kidney organoids were generated from human induced pluripotent stem cells. We overexpressed HIF-1α via plasmid transfection or treated DMOG (Dimethyloxallyl Glycine, an agent for HIF-1α stabilization and accumulation) in kidney progenitor cells to detect the endothelium. For the disease modeling study, we treated kidney organoid with cisplatin under hypoxia environment, with additional HIF-1α transfection.
RESULT
HIF-1α overexpression elicited kidney organoid vascularization. The endothelial cells and angiotool analysis parameters were increased in HIF-1α plasmid-transfected and DMOG-treated organoids. These angiogenesis processes were partially blocked by VEGFR inhibitors, semaxanib or axitinib. Cisplatin-induced kidney injury (Cleaved caspase 3) was protected by HIF-1α through the upregulation of CD31 and SOD2.
CONCLUSION
We demonstrated that HIF-1α elicited the process of kidney organoid vascularization and protected against cisplatin-induced kidney organoid injury in hypoxia environment.
Topics: Organoids; Kidney; Multipotent Stem Cells; Hypoxia-Inducible Factor 1, alpha Subunit; Humans; Models, Biological; Plasmids; Gene Expression; Stem Cells; Receptors, Vascular Endothelial Growth Factor; Angiogenesis Inhibitors; Angiogenesis; Axitinib; Cells, Cultured; Cisplatin; Cell Hypoxia; Kidney Diseases
PubMed: 37981699
DOI: 10.1186/s13287-023-03528-9 -
Endokrynologia Polska 2013Pheochromocytomas are benign or malignant neuroendocrine tumours. The unsatisfactory efficacy of the traditional therapeutic methods for patients with metastatic disease... (Comparative Study)
Comparative Study
INTRODUCTION
Pheochromocytomas are benign or malignant neuroendocrine tumours. The unsatisfactory efficacy of the traditional therapeutic methods for patients with metastatic disease results in a continuing search for more effective and targeted agents. Due to the increased vascularisation of these tumours, inhibitors of angiogenesis could be potentially a new group of drugs in pheochromocytoma/paraganglioma therapy.
MATERIAL AND METHODS
The aim of this study was to evaluate the influence of angiomodulators: VEGF (vascular endothelial growth factor) and five endogenous and exogenous antiangiogenic compounds (endostatin; IFN-alpha [interferon alpha]; rapamycin - mTOR [mammalian target of rapamycin] inhibitor; JV1-36 and SU5416 (semaxinib]) on the growth of rat pheochromocytoma PC12 cell line.
RESULTS
IFN-alpha (10(5) U/mL) strongly inhibited PC12 growth in a 72 h culture, increasing apoptosis and arresting the cell cycle. Rapamycin in a wide range of concentrations (10(-5) to 10(-8) M) induced a slight inhibitory effect on PC12 viability and decreased cell proliferation at the concentration of 10(-5) M. VEGF, endostatin and JV1-36 did not influence the growth of PC12.
CONCLUSIONS
The study has shown for the first time that IFN-a inhibited the growth of pheochromocytoma PC12 line and confirmed the inhibitory action of rapamycin on these cells. The results suggest that IFN-alpha and mTOR inhibitors could be potentially effective in the therapy of malignant pheochromocytoma, and encourage further study in this field.
Topics: Adrenal Gland Neoplasms; Angiogenesis Inhibitors; Animals; Antineoplastic Agents; Cell Proliferation; Endostatins; Growth Hormone-Releasing Hormone; Indoles; Interferon-alpha; Neovascularization, Pathologic; PC12 Cells; Pheochromocytoma; Pyrroles; Rats; Sirolimus; Tumor Cells, Cultured; Vascular Endothelial Growth Factor A
PubMed: 24186594
DOI: 10.5603/EP.2013.0020 -
Communications Biology Aug 2021Pulmonary arterial hypertension (PAH), is a fatal disease characterized by a pseudo-malignant phenotype. We investigated the expression and the role of the receptor...
Pulmonary arterial hypertension (PAH), is a fatal disease characterized by a pseudo-malignant phenotype. We investigated the expression and the role of the receptor tyrosine kinase Axl in experimental (i.e., monocrotaline and Su5416/hypoxia treated rats) and clinical PAH. In vitro Axl inhibition by R428 and Axl knock-down inhibited growth factor-driven proliferation and migration of non-PAH and PAH PASMCs. Conversely, Axl overexpression conferred a growth advantage. Axl declined in PAECs of PAH patients. Axl blockage inhibited BMP9 signaling and increased PAEC apoptosis, while BMP9 induced Axl phosphorylation. Gas6 induced SMAD1/5/8 phosphorylation and ID1/ID2 increase were blunted by BMP signaling obstruction. Axl association with BMPR2 was facilitated by Gas6/BMP9 stimulation and diminished by R428. In vivo R428 aggravated right ventricular hypertrophy and dysfunction, abrogated BMPR2 signaling, elevated pulmonary endothelial cell apoptosis and loss. Together, Axl is a key regulator of endothelial BMPR2 signaling and potential determinant of PAH.
Topics: Angiogenesis Inhibitors; Animals; Bone Morphogenetic Protein Receptors, Type II; Gene Expression Regulation; Indoles; Male; Monocrotaline; Pulmonary Arterial Hypertension; Pyrroles; Rats, Inbred WKY; Rats, Sprague-Dawley; Receptor Protein-Tyrosine Kinases; Rats
PubMed: 34429509
DOI: 10.1038/s42003-021-02531-1 -
Biomolecules Nov 2021Pulmonary hypertension (PH) is characterized by vascular remodeling caused by marked proliferation of pulmonary artery smooth muscle cells (PASMCs). Andrographolide...
Pulmonary hypertension (PH) is characterized by vascular remodeling caused by marked proliferation of pulmonary artery smooth muscle cells (PASMCs). Andrographolide (ANDRO) is a potent anti-inflammatory agent which possesses antioxidant, and has anticarcinogenic activity. The present study examined potential therapeutic effects of ANDRO on PH in both chronic hypoxia and Sugen5416/hypoxia mouse PH models. Effects of ANDRO were also studied in cultured human PASMCs isolated from either healthy donors or PH patients. In vivo, ANDRO decreased distal pulmonary arteries (PAs) remodeling, mean PA pressure and right ventricular hypertrophy in chronic hypoxia- and Sugen/hypoxia-induced PH in mice. ANDRO reduced cell viability, proliferation and migration, but increased cell apoptosis in the PASMCs isolated from PH patients. ANDRO also reversed the dysfunctional bone morphogenetic protein receptor type-2 (BMPR2) signaling, suppressed [Ca2] elevation, reactive oxygen species (ROS) generation, and the upregulated expression of IL-6 and IL-8, ET-1 and VEGF in PASMCs from PH patients. Moreover, ANDRO significantly attenuated the activation of TLR4/NF-κB, ERK- and JNK-MAPK signaling pathways and reversed the inhibition of p38-MAPK in PASMCs of PH patients. Further, ANDRO blocked hypoxia-triggered ROS generation by suppressing NADPH oxidase (NOX) activation and augmenting nuclear factor erythroid 2-related factor 2 (Nrf2) expression both in vitro and in vivo. Conventional pulmonary vasodilators have limited efficacy for the treatment of severe PH. We demonstrated that ANDRO may reverse pulmonary vascular remodeling through modulation of NOX/Nrf2-mediated oxidative stress and NF-κB-mediated inflammation. Our findings suggest that ANDRO may have therapeutic value in the treatment of PH.
Topics: Animals; Anti-Inflammatory Agents; Cell Movement; Cell Proliferation; Cell Survival; Cells, Cultured; Disease Models, Animal; Diterpenes; Female; Gene Expression Regulation; Humans; Hypertension, Pulmonary; Indoles; Male; Mice; Primary Cell Culture; Pyrroles; Signal Transduction; Vascular Remodeling
PubMed: 34944445
DOI: 10.3390/biom11121801