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Jucht AE, Scholz CC. PHD1-3 oxygen sensors in vivo-lessons learned from gene deletions. Pflugers Arch 2024; 476:1307-1337. [PMID: 38509356 PMCID: PMC11310289 DOI: 10.1007/s00424-024-02944-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 03/02/2024] [Accepted: 03/07/2024] [Indexed: 03/22/2024]
Abstract
Oxygen sensors enable cells to adapt to limited oxygen availability (hypoxia), affecting various cellular and tissue responses. Prolyl-4-hydroxylase domain 1-3 (PHD1-3; also called Egln1-3, HIF-P4H 1-3, HIF-PH 1-3) proteins belong to the Fe2+- and 2-oxoglutarate-dependent dioxygenase superfamily and utilise molecular oxygen (O2) alongside 2-oxoglutarate as co-substrate to hydroxylate two proline residues of α subunits of the dimeric hypoxia inducible factor (HIF) transcription factor. PHD1-3-mediated hydroxylation of HIF-α leads to its degradation and inactivation. Recently, various PHD inhibitors (PHI) have entered the clinics for treatment of renal anaemia. Pre-clinical analyses indicate that PHI treatment may also be beneficial in numerous other hypoxia-associated diseases. Nonetheless, the underlying molecular mechanisms of the observed protective effects of PHIs are only partly understood, currently hindering their translation into the clinics. Moreover, the PHI-mediated increase of Epo levels is not beneficial in all hypoxia-associated diseases and PHD-selective inhibition may be advantageous. Here, we summarise the current knowledge about the relevance and function of each of the three PHD isoforms in vivo, based on the deletion or RNA interference-mediated knockdown of each single corresponding gene in rodents. This information is crucial for our understanding of the physiological relevance and function of the PHDs as well as for elucidating their individual impact on hypoxia-associated diseases. Furthermore, this knowledge highlights which diseases may best be targeted by PHD isoform-selective inhibitors in case such pharmacologic substances become available.
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Affiliation(s)
- Agnieszka E Jucht
- Institute of Physiology, University of Zurich, Zurich, 8057, Switzerland
| | - Carsten C Scholz
- Institute of Physiology, University Medicine Greifswald, Friedrich-Ludwig-Jahn-Str. 15a, 17475, Greifswald, Germany.
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2
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Boothby M, Cho SH. Hypoxia and the Hypoxia-Inducible Factors in Lymphocyte Differentiation and Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1459:115-141. [PMID: 39017842 DOI: 10.1007/978-3-031-62731-6_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
Molecular oxygen doubles as a biomolecular building block and an element required for energy generation and metabolism in aerobic organisms. A variety of systems in mammalian cells sense the concentration of oxygen to which they are exposed and are tuned to the range present in our blood and tissues. The ability to respond to insufficient O2 in tissues is central to regulation of erythroid lineage cells, but challenges also are posed for immune cells by a need to adjust to very different oxygen concentrations. Hypoxia-inducible factors (HIFs) provide a major means of making such adjustments. For adaptive immunity, lymphoid lineages are initially defined in bone marrow niches; T lineage cells arise in the thymus, and B cells complete maturation in the spleen. Lymphocytes move from these first stops into microenvironments (bloodstream, lymphatics, and tissues) with distinct oxygenation in each. Herein, evidence pertaining to functions of the HIF transcription factors (TFs) in lymphocyte differentiation and function is reviewed. For the CD4+ and CD8+ subsets of T cells, the case is very strong that hypoxia and HIFs regulate important differentiation events and functions after the naïve lymphocytes emerge from the thymus. In the B lineage, the data indicate that HIF1 contributes to a balanced regulation of B-cell fates after antigen (Ag) activation during immunity. A model synthesized from the aggregate literature is that HIF in lymphocytes generally serves to modulate function in a manner dependent on the molecular context framed by other TFs and signals.
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Affiliation(s)
- Mark Boothby
- Departments of Pathology, Microbiology, Immunology (Molecular Pathogenesis Division), Vanderbilt University Medical Center, Nashville, TN, USA.
- Medicine (Rheumatology and Immunology Division), Vanderbilt University Medical Center, Nashville, TN, USA.
- Vanderbilt Institute for Infection, Inflammation, Immunity (VI4), Nashville, TN, USA.
| | - Sung Hoon Cho
- Departments of Pathology, Microbiology, Immunology (Molecular Pathogenesis Division), Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Inflammation, Immunity (VI4), Nashville, TN, USA
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3
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He R, He Y, Du R, Liu C, Chen Z, Zeng A, Song L. Revisiting of TAMs in tumor immune microenvironment: Insight from NF-κB signaling pathway. Biomed Pharmacother 2023; 165:115090. [PMID: 37390708 DOI: 10.1016/j.biopha.2023.115090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/20/2023] [Accepted: 06/26/2023] [Indexed: 07/02/2023] Open
Abstract
Tumor-associated macrophages (TAMs) are key components of tumor immune microenvironment and play a dual role in promoting tumor growth and anti-tumor immunity. Therefore, regulating TAMs has become a promising method in cancer immunotherapy. NF- κB pathway is the key regulatory pathway of TAMs. Targeting this pathway has shown the potential to improve tumor immune microenvironment. At present, there are still some controversies and the idea of combined therapy in this field. This article reviews the progress in the field of immunotherapy in improving tumor immune microenvironment by exploring the mechanism of regulating TAMs (including promoting M1 polarization, inhibiting M2 polarization and regulating TAMs infiltration).
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Affiliation(s)
- Rui He
- School of Medical and Life Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 611137, PR China
| | - Yan He
- School of Medical and Life Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 611137, PR China
| | - Ran Du
- College of Education and Psychology, Chengdu Normal University, Chengdu, Sichuan 611130, PR China
| | - Chenxin Liu
- School of Medical and Life Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 611137, PR China
| | - Zeran Chen
- School of Medical and Life Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 611137, PR China
| | - Anqi Zeng
- Institute of Translational Pharmacology and Clinical Application, Sichuan Academy of Chinese Medical Science, Chengdu, Sichuan 610041, PR China
| | - Linjiang Song
- School of Medical and Life Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 611137, PR China
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Kennel KB, Burmeister J, Radhakrishnan P, Giese NA, Giese T, Salfenmoser M, Gebhardt JM, Strowitzki MJ, Taylor CT, Wielockx B, Schneider M, Harnoss JM. The HIF-prolyl hydroxylases have distinct and nonredundant roles in colitis-associated cancer. JCI Insight 2022; 7:153337. [PMID: 36509284 DOI: 10.1172/jci.insight.153337] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 10/11/2022] [Indexed: 11/22/2022] Open
Abstract
Colitis-associated colorectal cancer (CAC) is a severe complication of inflammatory bowel disease (IBD). HIF-prolyl hydroxylases (PHD1, PHD2, and PHD3) control cellular adaptation to hypoxia and are considered promising therapeutic targets in IBD. However, their relevance in the pathogenesis of CAC remains elusive. We induced CAC in Phd1-/-, Phd2+/-, Phd3-/-, and WT mice with azoxymethane (AOM) and dextran sodium sulfate (DSS). Phd1-/- mice were protected against chronic colitis and displayed diminished CAC growth compared with WT mice. In Phd3-/- mice, colitis activity and CAC growth remained unaltered. In Phd2+/- mice, colitis activity was unaffected, but CAC growth was aggravated. Mechanistically, Phd2 deficiency (i) increased the number of tumor-associated macrophages in AOM/DSS-induced tumors, (ii) promoted the expression of EGFR ligand epiregulin in macrophages, and (iii) augmented the signal transducer and activator of transcription 3 and extracellular signal-regulated kinase 1/2 signaling, which at least in part contributed to aggravated tumor cell proliferation in colitis-associated tumors. Consistently, Phd2 deficiency in hematopoietic (Vav:Cre-Phd2fl/fl) but not in intestinal epithelial cells (Villin:Cre-Phd2fl/fl) increased CAC growth. In conclusion, the 3 different PHD isoenzymes have distinct and nonredundant effects, promoting (PHD1), diminishing (PHD2), or neutral (PHD3), on CAC growth.
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Affiliation(s)
- Kilian B Kennel
- Department of General, Visceral and Transplantation Surgery and
| | | | | | | | - Thomas Giese
- Institute of Immunology, University Hospital Heidelberg, Heidelberg, Germany
| | | | | | | | - Cormac T Taylor
- School of Medicine, Systems Biology Ireland, and the Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin, Ireland
| | - Ben Wielockx
- Institute for Clinical Chemistry and Laboratory Medicine, Dresden University of Technology, Dresden, Germany
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Cell-intrinsic factors governing quiescence vis-à-vis activation of adult hematopoietic stem cells. Mol Cell Biochem 2022; 478:1361-1382. [PMID: 36309884 DOI: 10.1007/s11010-022-04594-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 10/13/2022] [Indexed: 10/31/2022]
Abstract
Hematopoiesis is a highly complex process, regulated by both intrinsic and extrinsic factors. Often, these two regulatory arms work in tandem to maintain the steady-state condition of hematopoiesis. However, at times, certain intrinsic attributes of hematopoietic stem cells (HSCs) override the external stimuli and dominate the outcome. These could be genetic events like mutations or environmentally induced epigenetic or transcriptomic changes. Since leukemic stem cells (LSCs) share molecular pathways that also regulate normal HSCs, identifying specific, dominantly acting intrinsic factors could help in the development of novel therapeutic approaches. Here we have reviewed such dominantly acting intrinsic factors governing quiescence vis-à-vis activation of the HSCs in the face of external forces acting on them. For brevity, we have restricted our review to the articles dealing with adult HSCs of human and mouse origin that have been published in the last 10 years. Hematopoietic stem cells (HSCs) are closely associated with various stromal cells in their microenvironment and, thus, constantly receive signaling cues from them. The illustration depicts some dominantly acting intrinsic or cell-autonomous factors operative in the HSCs. These fall into various categories, such as epigenetic regulators, transcription factors, cell cycle regulators, tumor suppressor genes, signaling pathways, and metabolic regulators, which counteract the outcome of extrinsic signaling exerted by the HSC niche.
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Loss of sphingosine kinase 2 promotes the expansion of hematopoietic stem cells by improving their metabolic fitness. Blood 2022; 140:1686-1701. [PMID: 35881840 DOI: 10.1182/blood.2022016112] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 07/20/2022] [Indexed: 11/20/2022] Open
Abstract
Hematopoietic stem cells (HSCs) have reduced capacities to properly maintain and replenish the hematopoietic system during myelosuppressive injury or aging. Expanding and rejuvenating HSCs for therapeutic purposes has been a long-sought goal with limited progress. Here, we show that the enzyme Sphk2 (sphingosine kinase 2), which generates the lipid metabolite sphingosine-1-phosphate, is highly expressed in HSCs. The deletion of Sphk2 markedly promotes self-renewal and increases the regenerative potential of HSCs. More importantly, Sphk2 deletion globally preserves the young HSC gene expression pattern, improves the function, and sustains the multilineage potential of HSCs during aging. Mechanistically, Sphk2 interacts with prolyl hydroxylase 2 and the Von Hippel-Lindau protein to facilitate HIF1α ubiquitination in the nucleus independent of the Sphk2 catalytic activity. Deletion of Sphk2 increases hypoxic responses by stabilizing the HIF1α protein to upregulate PDK3, a glycolysis checkpoint protein for HSC quiescence, which subsequently enhances the function of HSCs by improving their metabolic fitness; specifically, it enhances anaerobic glycolysis but suppresses mitochondrial oxidative phosphorylation and generation of reactive oxygen species. Overall, targeting Sphk2 to enhance the metabolic fitness of HSCs is a promising strategy to expand and rejuvenate functional HSCs.
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Zuk A, Si Z, Loi S, Bommegowda S, Hoivik D, Danthi S, Molnar G, Csizmadia V, Rabinowitz M. Preclinical Characterization of Vadadustat (AKB-6548), an Oral Small Molecule Hypoxia-Inducible Factor Prolyl-4-Hydroxylase Inhibitor, for the Potential Treatment of Renal Anemia. J Pharmacol Exp Ther 2022; 383:11-24. [PMID: 35926869 DOI: 10.1124/jpet.122.001126] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 06/28/2022] [Accepted: 07/05/2022] [Indexed: 12/15/2022] Open
Abstract
Pharmacological inhibition of prolyl-4-hydroxylase domain (PHD) enzymes stabilizes hypoxia-inducible factors (HIFs), transcription factors that activate target genes that, among others, increase erythropoietin (EPO) synthesis, resulting in the production of new red blood cells (RBCs). Herein, we summarize the preclinical characteristics of the small molecule HIF prolyl-4-hydroxylase inhibitor vadadustat (AKB-6548), which is in development for the treatment of anemia in patients with chronic kidney disease (CKD). Vadadustat inhibits the enzyme activity of all three human PHD isozymes, PHD1, PHD2, and PHD3, with similar low nanomolar inhibitory constant values. PHD enzyme inhibition by vadadustat is competitive with endogenous cofactor 2-oxoglutarate and is insensitive to free iron concentration. In the human hepatocellular carcinoma cell line (Hep 3B) and human umbilical vein endothelial cells, PHD inhibition by vadadustat leads to the time- and concentration-dependent stabilization of HIF-1α and HIF-2α In Hep 3B cells, this in turn results in the synthesis and secretion of EPO; vascular endothelial growth factor is not measured at detectable levels. A single oral dose of vadadustat in rats potently increases circulating levels of EPO, and daily oral dosing for 14 days increases RBC indices in healthy rats and in the 5/6 nephrectomy model of CKD. In mice and dogs, once-daily repeat oral dosing increases hemoglobin and hematocrit. Vadadustat has a relatively short half-life in all nonclinical species evaluated and does not accumulate when administered as a single bolus dose (oral or intravenous) or upon repeat oral dosing. The pharmacological profile of vadadustat supports continued development for treatment of renal anemia. SIGNIFICANCE STATEMENT: Vadadustat (AKB-6548) is an orally bioavailable small molecule prolyl-4-hydroxylase inhibitor in development for anemia of chronic kidney disease. It is an equipotent inhibitor of the three human prolyl-4-hydroxylase domain isoforms, which activates erythropoiesis through stabilization of hypoxia-inducible factor (HIF)-1α and HIF-2α, increasing production of erythropoietin, without detectable stimulation of vascular endothelial growth factor.
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Affiliation(s)
- Anna Zuk
- Department of Research and Early Development, Akebia Therapeutics, Inc., Cambridge, Massachusetts (A.Z, Z.S., S.L, S.B., D.H., S.D., G.M., V.C., M.R)
| | - Zhihai Si
- Department of Research and Early Development, Akebia Therapeutics, Inc., Cambridge, Massachusetts (A.Z, Z.S., S.L, S.B., D.H., S.D., G.M., V.C., M.R)
| | - Sally Loi
- Department of Research and Early Development, Akebia Therapeutics, Inc., Cambridge, Massachusetts (A.Z, Z.S., S.L, S.B., D.H., S.D., G.M., V.C., M.R)
| | - Santhosh Bommegowda
- Department of Research and Early Development, Akebia Therapeutics, Inc., Cambridge, Massachusetts (A.Z, Z.S., S.L, S.B., D.H., S.D., G.M., V.C., M.R)
| | - Debie Hoivik
- Department of Research and Early Development, Akebia Therapeutics, Inc., Cambridge, Massachusetts (A.Z, Z.S., S.L, S.B., D.H., S.D., G.M., V.C., M.R)
| | - Sanjay Danthi
- Department of Research and Early Development, Akebia Therapeutics, Inc., Cambridge, Massachusetts (A.Z, Z.S., S.L, S.B., D.H., S.D., G.M., V.C., M.R)
| | - Gyongyi Molnar
- Department of Research and Early Development, Akebia Therapeutics, Inc., Cambridge, Massachusetts (A.Z, Z.S., S.L, S.B., D.H., S.D., G.M., V.C., M.R)
| | - Vilmos Csizmadia
- Department of Research and Early Development, Akebia Therapeutics, Inc., Cambridge, Massachusetts (A.Z, Z.S., S.L, S.B., D.H., S.D., G.M., V.C., M.R)
| | - Michael Rabinowitz
- Department of Research and Early Development, Akebia Therapeutics, Inc., Cambridge, Massachusetts (A.Z, Z.S., S.L, S.B., D.H., S.D., G.M., V.C., M.R)
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8
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Osuru HP, Lavallee M, Thiele RH. Molecular and Cellular Response of the Myocardium (H9C2 Cells) Towards Hypoxia and HIF-1α Inhibition. Front Cardiovasc Med 2022; 9:711421. [PMID: 35928940 PMCID: PMC9343679 DOI: 10.3389/fcvm.2022.711421] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 06/21/2022] [Indexed: 11/30/2022] Open
Abstract
Introduction Oxidative phosphorylation is an essential feature of Animalian life. Multiple adaptations have developed to protect against hypoxia, including hypoxia-inducible-factors (HIFs). The major role of HIFs may be in protecting against oxidative stress, not the preservation of high-energy phosphates. The precise mechanism(s) of HIF protection is not completely understood. Materials and Methods To better understand the role of hypoxia-inducible-factor-1, we exposed heart/myocardium cells (H9c2) to both normoxia and hypoxia, as well as cobalt chloride (prolyl hydroxylase inhibitor), echniomycin (HIF inhibitor), A2P (anti-oxidant), and small interfering RNA to beclin-1. We measured cell viability, intracellular calcium and adenosine triphosphate, NADP/NADPH ratios, total intracellular reactive oxidative species levels, and markers of oxidative and antioxidant levels measured. Results Hypoxia (1%) leads to increased intracellular Ca2+ levels, and this response was inhibited by A2P and echinomycin (ECM). Exposure of H9c2 cells to hypoxia also led to an increase in both mRNA and protein expression for Cav 1.2 and Cav 1.3. Exposure of H9c2 cells to hypoxia led to a decrease in intracellular ATP levels and a sharp reduction in total ROS, SOD, and CAT levels. The impact of hypoxia on ROS was reversed with HIF-1 inhibition through ECM. Exposure of H9c2 cells to hypoxia led to an increase in Hif1a, VEGF and EPO protein expression, as well as a decrease in mitochondrial DNA. Both A2P and ECM attenuated this response to varying degrees. Conclusion Hypoxia leads to increased intracellular Ca2+, and inhibition of HIF-1 attenuates the increase in intracellular Ca2+ that occurs with hypoxia. HIF-1 expression leads to decreased adenosine triphosphate levels, but the role of HIF-1 on the production of reactive oxidative species remains uncertain. Anti-oxidants decrease HIF-1 expression in the setting of hypoxia and attenuate the increase in Ca2+ that occurs during hypoxia (with no effect during normoxia). Beclin-1 appears to drive autophagy in the setting of hypoxia (through ATG5) but not in normoxia. Additionally, Beclin-1 is a powerful driver of reactive oxidative species production and plays a role in ATP production. HIF-1 inhibition does not affect autophagy in the setting of hypoxia, suggesting that there are other drivers of autophagy that impact beclin-1.
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Christoph M, Pflücke C, Mensch M, Augstein A, Jellinghaus S, Ende G, Mierke J, Franke K, Wielockx B, Ibrahim K, Poitz DM. Myeloid PHD2 deficiency accelerates neointima formation via Hif-1α. Mol Immunol 2022; 149:48-58. [PMID: 35724581 DOI: 10.1016/j.molimm.2022.06.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 06/04/2022] [Accepted: 06/08/2022] [Indexed: 11/26/2022]
Abstract
The key players of the hypoxic response are the hypoxia-inducible factors (Hif), whose α-subunits are tightly regulated by Prolyl-4-hydroxylases (PHD), predominantly by PHD2. Monocytes/Macrophages are involved in atherosclerosis but also restenosis and were found at hypoxic and sites of the lesion. Little is known about the role of the myeloid PHD2 in atherosclerosis and neointima formation. The study aimed to investigate the consequences of a myeloid deficiency of PHD2 in the process of neointima formation using an arterial denudation model. LysM-cre mice were crossed with PHD2fl/fl, PHD2fl/fl/Hif1αfl/fl and PHD2fl/fl/Hif2αfl/fl to get myeloid specific knockout of PHD2 and the Hif-α subunits. Denudation of the femoral artery was performed and animals were fed a western type diet afterwards with analysis of neointima formation 5 and 35 days after denudation. Increased neointima formation in myeloid PHD2 knockouts was observed, which was blunted by double-knockout of PHD2 and Hif1α whereas double knockout of PHD2 and Hif-2α showed comparable lesions to the PHD2 knockouts. Macrophage infiltration was comparable to the neointima formation, suggesting a more inflammatory reaction, and was accompanied by increased intimal VEGF-A expression. Collagen-content inversely correlated to the extent of neointima formation suggesting a destabilization of the plaque. This effect might be triggered by macrophage polarization. Therefore, in vitro results showed a distinct expression pattern in differentially polarized macrophages with high expression of Hif-1α, VEGF and MMP-1 in proinflammatory M1 macrophages. In conclusion, the results show that myeloid Hif-1α is involved in neointima hyperplasia. Our in vivo and in vitro data reveal a central role for this transcription factor in driving plaque-vascularization accompanied by matrix-degradation leading to plaque destabilization.
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Affiliation(s)
- Marian Christoph
- Internal Medicine and Cardiology, Heart Center Dresden, University Hospital at the Technische Universität, Dresden, Germany; Technische Universität, Dresden Campus, Chemnitz, Germany
| | - Christian Pflücke
- Internal Medicine and Cardiology, Heart Center Dresden, University Hospital at the Technische Universität, Dresden, Germany
| | - Matthias Mensch
- Internal Medicine and Cardiology, Heart Center Dresden, University Hospital at the Technische Universität, Dresden, Germany
| | - Antje Augstein
- Internal Medicine and Cardiology, Heart Center Dresden, University Hospital at the Technische Universität, Dresden, Germany
| | - Stefanie Jellinghaus
- Internal Medicine and Cardiology, Heart Center Dresden, University Hospital at the Technische Universität, Dresden, Germany
| | - Georg Ende
- Internal Medicine and Cardiology, Heart Center Dresden, University Hospital at the Technische Universität, Dresden, Germany
| | - Johannes Mierke
- Internal Medicine and Cardiology, Heart Center Dresden, University Hospital at the Technische Universität, Dresden, Germany
| | - Kristin Franke
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany
| | - Ben Wielockx
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany
| | - Karim Ibrahim
- Internal Medicine and Cardiology, Heart Center Dresden, University Hospital at the Technische Universität, Dresden, Germany; Technische Universität, Dresden Campus, Chemnitz, Germany
| | - David M Poitz
- Internal Medicine and Cardiology, Heart Center Dresden, University Hospital at the Technische Universität, Dresden, Germany; Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany.
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Broeker KAE, Fuchs MAA, Schrankl J, Lehrmann C, Schley G, Todorov VT, Hugo C, Wagner C, Kurtz A. Prolyl-4-hydroxylases 2 and 3 control erythropoietin production in renin-expressing cells of mouse kidneys. J Physiol 2021; 600:671-694. [PMID: 34863041 DOI: 10.1113/jp282615] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 11/29/2021] [Indexed: 12/30/2022] Open
Abstract
Activation of the hypoxia-signalling pathway induced by deletion of the ubiquitin-ligase von Hippel-Lindau protein causes an endocrine shift of renin-producing cells to erythropoietin (EPO)-expressing cells. However, the underlying mechanisms have not yet been investigated. Since oxygen-regulated stability of hypoxia-inducible transcription factors relevant for EPO expression is dependent on the activity of prolyl-4-hydroxylases (PHD) 2 and 3, this study aimed to determine the relevance of different PHD isoforms for the EPO expression in renin-producing cells in vivo. For this purpose, mice with inducible renin cell-specific deletions of different PHD isoforms were analysed. Our study shows that there are two subgroups of renal renin-expressing cells, juxtaglomerular renin+ cells and platelet-derived growth factor receptor-β+ interstitial renin+ cells. These interstitial renin+ cells belong to the cell pool of native EPO-producing cells and are able to express EPO and renin in parallel. In contrast, co-deletion of PHD2 and PHD3, but not PHD2 deletion alone, induces EPO expression in juxtaglomerular and hyperplastic renin+ cells and downregulates renin expression. A strong basal PHD3 expression in juxtaglomerular renin+ cells seems to prevent the hypoxia-inducible transcription factor-2-dependent phenotype shift into EPO cells. In summary, PHDs seem important for the stabilization of the juxtaglomerular renin cell phenotype. Moreover, these findings reveal tubulointerstitial cells as a novel site of renal renin expression and suggest a high endocrine plasticity of these cells. Our data concerning the distinct expression patterns and functions of PHD2 and PHD3 provide new insights into the regulation of renin-producing cells and highlight the need for selective PHD inhibitors. KEY POINTS: Renal renin-expressing cells can be clearly distinguished into two subgroups, the typical juxtaglomerular renin-producing cells and interstitial renin+ cells. Interstitial renin+ cells belong to the cell pool of native erythropoietin (EPO)-producing cells, show a fast EPO response to acute hypoxia-inducible factor-2 (HIF-2) stabilization and are able to express EPO and renin in parallel. Only co-deletion of the prolyl-4-hydroxylases (PHD) 2 and 3, but not PHD2 deletion alone, induces EPO expression in juxtaglomerular renin+ cells. Chronic HIF-2 stabilization in juxtaglomerular renin-expressing cells leads to their phenotypic shift into EPO-producing cells. A strong basal PHD3 expression in juxtaglomerular renin+ cells seems to prevent a HIF-2-dependent phenotype shift into EPO cells suggesting PHD3 fulfils a stabilizer function for the juxtaglomerular renin cell phenotype.
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Affiliation(s)
| | | | - Julia Schrankl
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Claudia Lehrmann
- Institute of Physiology II, University of Regensburg, Regensburg, Germany
| | - Gunnar Schley
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Vladimir T Todorov
- Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, Dresden, Germany
| | - Christian Hugo
- Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, Dresden, Germany
| | - Charlotte Wagner
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Armin Kurtz
- Institute of Physiology, University of Regensburg, Regensburg, Germany
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11
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Watts D, Bechmann N, Meneses A, Poutakidou IK, Kaden D, Conrad C, Krüger A, Stein J, El-Armouche A, Chavakis T, Eisenhofer G, Peitzsch M, Wielockx B. HIF2α regulates the synthesis and release of epinephrine in the adrenal medulla. J Mol Med (Berl) 2021; 99:1655-1666. [PMID: 34480587 PMCID: PMC8542008 DOI: 10.1007/s00109-021-02121-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 07/16/2021] [Accepted: 07/20/2021] [Indexed: 02/06/2023]
Abstract
The adrenal gland and its hormones regulate numerous fundamental biological processes; however, the impact of hypoxia signaling on adrenal function remains poorly understood. Here, we reveal that deficiency of HIF (hypoxia inducible factors) prolyl hydroxylase domain protein-2 (PHD2) in the adrenal medulla of mice results in HIF2α-mediated reduction in phenylethanolamine N-methyltransferase (PNMT) expression, and consequent reduction in epinephrine synthesis. Simultaneous loss of PHD2 in renal erythropoietin (EPO)-producing cells (REPCs) stimulated HIF2α-driven EPO overproduction, excessive RBC formation (erythrocytosis), and systemic hypoglycemia, which is necessary and sufficient to enhance exocytosis of epinephrine from the adrenal medulla. Based on these results, we propose that the PHD2-HIF2α axis in the adrenal medulla regulates the synthesis of epinephrine, whereas in REPCs, it indirectly induces the release of this hormone. Our findings are also highly relevant to the testing of small molecule PHD inhibitors in phase III clinical trials for patients with renal anemia. KEY MESSAGES: HIF2α and not HIF1α modulates PNMT during epinephrine synthesis in chromaffin cells. The PHD2-HIF2α-EPO axis induces erythrocytosis and hypoglycemia. Reduced systemic glucose facilitates exocytosis of epinephrine from adrenal gland.
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Affiliation(s)
- Deepika Watts
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Nicole Bechmann
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany.,Department of Experimental Diabetology, German Institute of Human Nutrition Potsdam-Rehbruecke, 14558, Nuthetal, Germany.,German Center for Diabetes Research (DZD), 85764, München-Neuherberg, Germany
| | - Ana Meneses
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Ioanna K Poutakidou
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Denise Kaden
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Catleen Conrad
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Anja Krüger
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Johanna Stein
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Ali El-Armouche
- Department of Pharmacology and Toxicology, Medical Faculty, Technische Universität Dresden, 01307, Dresden, Germany
| | - Triantafyllos Chavakis
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Graeme Eisenhofer
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany.,Department of Medicine III, Medical Faculty, Technische Universität Dresden, 01307, Dresden, Germany
| | - Mirko Peitzsch
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Ben Wielockx
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany.
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12
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HIF2α is a direct regulator of neutrophil motility. Blood 2021; 137:3416-3427. [PMID: 33619535 DOI: 10.1182/blood.2020007505] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 01/24/2021] [Indexed: 12/19/2022] Open
Abstract
Orchestrated recruitment of neutrophils to inflamed tissue is essential during the initiation of inflammation. Inflamed areas are usually hypoxic, and adaptation to reduced oxygen pressure is typically mediated by hypoxia pathway proteins. However, it remains unclear how these factors influence the migration of neutrophils to and at the site of inflammation during their transmigration through the blood-endothelial cell barrier, as well as their motility in the interstitial space. Here, we reveal that activation of hypoxia-inducible factor 2 (HIF2α) as a result of a deficiency in HIF prolyl hydroxylase domain protein 2 (PHD2) boosts neutrophil migration specifically through highly confined microenvironments. In vivo, the increased migratory capacity of PHD2-deficient neutrophils resulted in massive tissue accumulation in models of acute local inflammation. Using systematic RNA sequencing analyses and mechanistic approaches, we identified RhoA, a cytoskeleton organizer, as the central downstream factor that mediates HIF2α-dependent neutrophil motility. Thus, we propose that the novel PHD2-HIF2α-RhoA axis is vital to the initial stages of inflammation because it promotes neutrophil movement through highly confined tissue landscapes.
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13
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Lawson H, Sepulveda C, van de Lagemaat LN, Durko J, Barile M, Tavosanis A, Georges E, Shmakova A, Timms P, Carter RN, Allen L, Campos J, Vukovic M, Guitart AV, Giles P, O'Shea M, Vernimmen D, Morton NM, Rodrigues NP, Göttgens B, Schofield CJ, Lengeling A, O'Carroll D, Kranc KR. JMJD6 promotes self-renewal and regenerative capacity of hematopoietic stem cells. Blood Adv 2021; 5:889-899. [PMID: 33560400 PMCID: PMC7876897 DOI: 10.1182/bloodadvances.2020002702] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 12/01/2020] [Indexed: 12/19/2022] Open
Abstract
Lifelong multilineage hematopoiesis critically depends on rare hematopoietic stem cells (HSCs) that reside in the hypoxic bone marrow microenvironment. Although the role of the canonical oxygen sensor hypoxia-inducible factor prolyl hydroxylase has been investigated extensively in hematopoiesis, the functional significance of other members of the 2-oxoglutarate (2-OG)-dependent protein hydroxylase family of enzymes remains poorly defined in HSC biology and multilineage hematopoiesis. Here, by using hematopoietic-specific conditional gene deletion, we reveal that the 2-OG-dependent protein hydroxylase JMJD6 is essential for short- and long-term maintenance of the HSC pool and multilineage hematopoiesis. Additionally, upon hematopoietic injury, Jmjd6-deficient HSCs display a striking failure to expand and regenerate the hematopoietic system. Moreover, HSCs lacking Jmjd6 lose multilineage reconstitution potential and self-renewal capacity upon serial transplantation. At the molecular level, we found that JMJD6 functions to repress multiple processes whose downregulation is essential for HSC integrity, including mitochondrial oxidative phosphorylation (OXPHOS), protein synthesis, p53 stabilization, cell cycle checkpoint progression, and mTORC1 signaling. Indeed, Jmjd6-deficient primitive hematopoietic cells display elevated basal and maximal mitochondrial respiration rates and increased reactive oxygen species (ROS), prerequisites for HSC failure. Notably, an antioxidant, N-acetyl-l-cysteine, rescued HSC and lymphoid progenitor cell depletion, indicating a causal impact of OXPHOS-mediated ROS generation upon Jmjd6 deletion. Thus, JMJD6 promotes HSC maintenance and multilineage differentiation potential by suppressing fundamental pathways whose activation is detrimental for HSC function.
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Affiliation(s)
- Hannah Lawson
- Laboratory of Haematopoietic Stem Cell and Leukaemia Biology, Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Catarina Sepulveda
- Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Louie N van de Lagemaat
- Laboratory of Haematopoietic Stem Cell and Leukaemia Biology, Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
- Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Jozef Durko
- Laboratory of Haematopoietic Stem Cell and Leukaemia Biology, Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Melania Barile
- Department of Haematology, Wellcome and Medical Research Council Cambridge Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, United Kingdom
| | - Andrea Tavosanis
- Laboratory of Haematopoietic Stem Cell and Leukaemia Biology, Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Elise Georges
- Laboratory of Haematopoietic Stem Cell and Leukaemia Biology, Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Alena Shmakova
- Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Penny Timms
- Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Roderick N Carter
- Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Lewis Allen
- Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Joana Campos
- Laboratory of Haematopoietic Stem Cell and Leukaemia Biology, Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Milica Vukovic
- Laboratory of Haematopoietic Stem Cell and Leukaemia Biology, Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Amelie V Guitart
- Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Peter Giles
- Wales Gene Park and Wales Cancer Research Centre, Division of Cancer and Genetics, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Marie O'Shea
- Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Douglas Vernimmen
- Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Nicholas M Morton
- Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Neil P Rodrigues
- European Cancer Stem Cell Research Institute, School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Berthold Göttgens
- Department of Haematology, Wellcome and Medical Research Council Cambridge Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, University of Cambridge, Cambridge, United Kingdom
| | - Christopher J Schofield
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | - Andreas Lengeling
- Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
- Administrative Headquarters, Max Planck Society, Munich, Germany; and
| | - Dónal O'Carroll
- Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, United Kingdom
- Institute for Stem Cell Research and
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Kamil R Kranc
- Laboratory of Haematopoietic Stem Cell and Leukaemia Biology, Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
- Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, United Kingdom
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14
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HIF1α is a direct regulator of steroidogenesis in the adrenal gland. Cell Mol Life Sci 2021; 78:3577-3590. [PMID: 33464382 PMCID: PMC8038963 DOI: 10.1007/s00018-020-03750-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 12/17/2020] [Accepted: 12/23/2020] [Indexed: 12/15/2022]
Abstract
Endogenous steroid hormones, especially glucocorticoids and mineralocorticoids, derive from the adrenal cortex, and drastic or sustained changes in their circulatory levels affect multiple organ systems. Although hypoxia signaling in steroidogenesis has been suggested, knowledge on the true impact of the HIFs (Hypoxia-Inducible Factors) in the adrenocortical cells of vertebrates is scant. By creating a unique set of transgenic mouse lines, we reveal a prominent role for HIF1α in the synthesis of virtually all steroids in vivo. Specifically, mice deficient in HIF1α in adrenocortical cells displayed enhanced levels of enzymes responsible for steroidogenesis and a cognate increase in circulatory steroid levels. These changes resulted in cytokine alterations and changes in the profile of circulatory mature hematopoietic cells. Conversely, HIF1α overexpression resulted in the opposite phenotype of insufficient steroid production due to impaired transcription of necessary enzymes. Based on these results, we propose HIF1α to be a vital regulator of steroidogenesis as its modulation in adrenocortical cells dramatically impacts hormone synthesis with systemic consequences. In addition, these mice can have potential clinical significances as they may serve as essential tools to understand the pathophysiology of hormone modulations in a number of diseases associated with metabolic syndrome, auto-immunity or even cancer.
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15
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Lee HY, Hong IS. Metabolic Regulation and Related Molecular Mechanisms in Various Stem Cell Functions. Curr Stem Cell Res Ther 2020; 15:531-546. [PMID: 32394844 DOI: 10.2174/1574888x15666200512105347] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 02/11/2020] [Accepted: 03/02/2020] [Indexed: 02/07/2023]
Abstract
Recent studies on the mechanisms that link metabolic changes with stem cell fate have deepened our understanding of how specific metabolic pathways can regulate various stem cell functions during the development of an organism. Although it was originally thought to be merely a consequence of the specific cell state, metabolism is currently known to play a critical role in regulating the self-renewal capacity, differentiation potential, and quiescence of stem cells. Many studies in recent years have revealed that metabolic pathways regulate various stem cell behaviors (e.g., selfrenewal, migration, and differentiation) by modulating energy production through glycolysis or oxidative phosphorylation and by regulating the generation of metabolites, which can modulate multiple signaling pathways. Therefore, a more comprehensive understanding of stem cell metabolism could allow us to establish optimal culture conditions and differentiation methods that would increase stem cell expansion and function for cell-based therapies. However, little is known about how metabolic pathways regulate various stem cell functions. In this context, we review the current advances in metabolic research that have revealed functional roles for mitochondrial oxidative phosphorylation, anaerobic glycolysis, and oxidative stress during the self-renewal, differentiation and aging of various adult stem cell types. These approaches could provide novel strategies for the development of metabolic or pharmacological therapies to promote the regenerative potential of stem cells and subsequently promote their therapeutic utility.
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Affiliation(s)
- Hwa-Yong Lee
- Department of Biomedical Science, Jungwon University, 85 Goesan-eup, Munmu-ro, Goesan-gun, Chungcheongbuk-do 367-700, Korea
| | - In-Sun Hong
- Department of Health Sciences and Technology, GAIHST, Gachon University, Incheon 21999, Korea
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16
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Schley G, Grampp S, Goppelt-Struebe M. Inhibition of oxygen-sensing prolyl hydroxylases increases lipid accumulation in human primary tubular epithelial cells without inducing ER stress. Cell Tissue Res 2020; 381:125-140. [PMID: 32189058 PMCID: PMC7306052 DOI: 10.1007/s00441-020-03186-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 02/03/2020] [Indexed: 12/18/2022]
Abstract
The role of the hypoxia-inducible transcription factor (HIF) pathway in renal lipid metabolism is largely unknown. As HIF stabilizing prolyl hydroxylase (PHD) inhibitors are currently investigated in clinical trials for the treatment of renal anemia, we studied the effects of genetic deletion and pharmacological inhibition of PHDs on renal lipid metabolism in transgenic mice and human primary tubular epithelial cells (hPTEC). Tubular cell-specific deletion of HIF prolyl hydroxylase 2 (Phd2) increased the size of Oil Red-stained lipid droplets in mice. In hPTEC, the PHD inhibitors (PHDi) DMOG and ICA augmented lipid accumulation, which was visualized by Oil Red staining and assessed by microscopy and an infrared imaging system. PHDi-induced lipid accumulation required the exogenous availability of fatty acids and was observed in both proximal and distal hPTEC. PHDi treatment was not associated with structural features of cytotoxicity in contrast to treatment with the immunosuppressant cyclosporine A (CsA). PHDi and CsA differentially upregulated the expression of the lipid droplet-associated genes PLIN2, PLIN4 and HILPDA. Both PHDi and CsA activated AMP-activated protein kinase (AMPK) indicating the initiation of a metabolic stress response. However, only CsA triggered endoplasmic reticulum (ER) stress as determined by the increased mRNA expression of multiple ER stress markers but CsA-induced ER stress was not linked to lipid accumulation. Our data raise the possibility that PHD inhibition may protect tubular cells from toxic free fatty acids by trapping them as triacylglycerides in lipid droplets. This mechanism might contribute to the renoprotective effects of PHDi in experimental kidney diseases.
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Affiliation(s)
- Gunnar Schley
- Department of Nephrology and Hypertension, Friedrich-Alexander University Erlangen-Nürnberg and University Hospital Erlangen, Loschgestrasse 8, 91054, Erlangen, Germany.
| | - Steffen Grampp
- Department of Nephrology and Hypertension, Friedrich-Alexander University Erlangen-Nürnberg and University Hospital Erlangen, Loschgestrasse 8, 91054, Erlangen, Germany
| | - Margarete Goppelt-Struebe
- Department of Nephrology and Hypertension, Friedrich-Alexander University Erlangen-Nürnberg and University Hospital Erlangen, Loschgestrasse 8, 91054, Erlangen, Germany
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17
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Rabe JL, Hernandez G, Chavez JS, Mills TS, Nerlov C, Pietras EM. CD34 and EPCR coordinately enrich functional murine hematopoietic stem cells under normal and inflammatory conditions. Exp Hematol 2019; 81:1-15.e6. [PMID: 31863798 DOI: 10.1016/j.exphem.2019.12.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 12/03/2019] [Accepted: 12/15/2019] [Indexed: 02/06/2023]
Abstract
Hematopoiesis is dynamically regulated to maintain blood system function under nonhomeostatic conditions such as inflammation and injury. However, common surface marker and hematopoietic stem cell (HSC) reporter systems used for prospective enrichment of HSCs have been less rigorously tested in these contexts. Here, we use two surface markers, EPCR/CD201 and CD34, to re-analyze dynamic changes in the HSC-enriched phenotypic SLAM compartment in a mouse model of chronic interleukin (IL)-1 exposure. EPCR and CD34 coordinately identify four functionally and molecularly distinct compartments within the SLAM fraction, including an EPCR+/CD34- fraction whose long-term serial repopulating activity is only modestly impacted by chronic IL-1 exposure, relative to unfractionated SLAM cells. Notably, the other three fractions expand in frequency following IL-1 treatment and represent actively proliferating, lineage-primed cell states with limited long-term repopulating potential. Importantly, we find that the Fgd5-ZSGreen HSC reporter mouse enriches for molecularly and functionally intact HSCs regardless of IL-1 exposure. Together, our findings provide further evidence of dynamic heterogeneity within a commonly used HSC-enriched phenotypic compartment under stress conditions. Importantly, they also indicate that stringency of prospective isolation approaches can enhance interpretation of findings related to HSC function when studying models of hematopoietic stress.
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Affiliation(s)
- Jennifer L Rabe
- Division of Hematology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Giovanny Hernandez
- Division of Hematology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - James S Chavez
- Division of Hematology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Taylor S Mills
- Division of Hematology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Claus Nerlov
- MRC Molecular Hematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Eric M Pietras
- Division of Hematology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA; Department of Immunology & Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
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18
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Wang L, Niu Z, Wang X, Li Z, Liu Y, Luo F, Yan X. PHD2 exerts anti-cancer and anti-inflammatory effects in colon cancer xenografts mice via attenuating NF-κB activity. Life Sci 2019; 242:117167. [PMID: 31838134 DOI: 10.1016/j.lfs.2019.117167] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 11/29/2019] [Accepted: 12/09/2019] [Indexed: 02/05/2023]
Abstract
Recent studies suggested that prolyl hydroxylase 2 (PHD2) functions as an important regulator in vascular inflammation and Streptococcus pneumonia infection. However, whether PHD2 contributed to tumor progression prompted by intratumoral inflammation remains elusive. In this study, the effects of PHD2 in colon cancer were evaluated, and the underlying molecular mechanisms were investigated. The results showed that overexpressing PHD2 exerted proliferative and migratory inhibition in colon cancer cells. The expression of cell cycle and epithelial-mesenchymal transition (EMT)-associated proteins were changed: CyclinD1, CDK4, N-cadherin, and Vimentin were down-regulated, while E-cadherin was up-regulated in PHD2-overexpressing colon cancer cells. Moreover, in colon cancer xenograft mice, PHD2 overexpression suppressed tumor growth accompanied by decreased Ki67 expression. Importantly, we further demonstrated that overexpressing PHD2 attenuated inflammation in colon cancer xenograft mice through weakening accumulation of myeloid-derived suppressor cells (MDSCs) and M2-like tumor-associated macrophages (TAMs), as well as secretions of pro-inflammatory cytokines including G-CSF, TNF-α, IL-6, IL-8, IL-1β, and IL-4. Mechanistically, PHD2 overexpression obviously suppressed NF-κB activity through decreasing phosphorylated IκB-α while increasing cytoplasmic NF-κB p65 levels in colon cancer. Our findings support the anti-cancer and anti-inflammatory roles of PHD2 and offer a preclinical proof of tumor progression regulated by cancer cells and inflammation.
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Affiliation(s)
- Li Wang
- Lung Cancer Center, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Zhendong Niu
- Department of Emergency Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Xia Wang
- Lung Cancer Center, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, Sichuan, China; Department of Medical Oncology, Ganzhou City People's Hospital, Ganzhou, Jiangxi, China
| | - Zhixi Li
- Lung Cancer Center, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Yanyang Liu
- Lung Cancer Center, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Feng Luo
- Lung Cancer Center, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, Sichuan, China.
| | - Xi Yan
- Lung Cancer Center, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, Sichuan, China.
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19
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Wielockx B, Grinenko T, Mirtschink P, Chavakis T. Hypoxia Pathway Proteins in Normal and Malignant Hematopoiesis. Cells 2019; 8:cells8020155. [PMID: 30781787 PMCID: PMC6406588 DOI: 10.3390/cells8020155] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 02/06/2019] [Accepted: 02/08/2019] [Indexed: 12/25/2022] Open
Abstract
The regulation of oxygen (O₂) levels is crucial in embryogenesis and adult life, as O₂ controls a multitude of key cellular functions. Low oxygen levels (hypoxia) are relevant for tissue physiology as they are integral to adequate metabolism regulation and cell fate. Hence, the hypoxia response is of utmost importance for cell, organ and organism function and is dependent on the hypoxia-inducible factor (HIF) pathway. HIF pathway activity is strictly regulated by the family of oxygen-sensitive HIF prolyl hydroxylase domain (PHD) proteins. Physiologic hypoxia is a hallmark of the hematopoietic stem cell (HSC) niche in the bone marrow. This niche facilitates HSC quiescence and survival. The present review focuses on current knowledge and the many open questions regarding the impact of PHDs/HIFs and other proteins of the hypoxia pathway on the HSC niche and on normal and malignant hematopoiesis.
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Affiliation(s)
- Ben Wielockx
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, 01307 Dresden, Germany.
| | - Tatyana Grinenko
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, 01307 Dresden, Germany.
| | - Peter Mirtschink
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, 01307 Dresden, Germany.
| | - Triantafyllos Chavakis
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, 01307 Dresden, Germany.
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20
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Abstract
INTRODUCTION Hypoxia-inducible transcription factors have been identified as regulators of adaptive responses to hypoxia. Over the past 20 years, more than 8000 papers have described their increasingly complex role and regulation in cancer. Presently, it is recognized that hypoxia-inducible factors (HIFs) are regulated by oxygen-dependent and oxygen-independent mechanisms in cancer development; the list of their targets has increased to include more than 500 genes involved in most hallmarks of cancer. Areas covered: Most literature describes the function of HIF factors in solid tumors; however, in the past 10 years, evidence has steadily accumulated to indicate that HIFs are implicated in hematological malignancies. This review summarizes our current understanding of the function and regulation of HIF factors in hematopoiesis and leukemia. Moreover, we provide an update on pharmacological inhibitors of this pathway that have shown promising therapeutic effects in clinical trials or leukemia pre-clinical models. Expert opinion: The inhibition of the function of HIF factors may provide an interesting approach for treating leukemia. We posit that before moving into the clinic, we should (i) fully characterize the outcome of HIF inhibition in specific leukemia contexts (ii) test the possibility of combining HIF-targeting strategies with cytotoxic compounds and (iii) consider patient selection to increase therapeutic efficacy.
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Affiliation(s)
- Daniela Magliulo
- a Vita-Salute San Raffaele University , Milan , Italy.,b Preclinical Models of Cancer Laboratory, Division of Experimental Oncology , San Raffaele Scientific Institute , Milan , Italy
| | - Rosa Bernardi
- b Preclinical Models of Cancer Laboratory, Division of Experimental Oncology , San Raffaele Scientific Institute , Milan , Italy
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21
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Hematopoietic Stem Cells but Not Multipotent Progenitors Drive Erythropoiesis during Chronic Erythroid Stress in EPO Transgenic Mice. Stem Cell Reports 2018; 10:1908-1919. [PMID: 29754961 PMCID: PMC5989815 DOI: 10.1016/j.stemcr.2018.04.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 04/13/2018] [Accepted: 04/16/2018] [Indexed: 12/30/2022] Open
Abstract
The hematopoietic stem cell (HSC) compartment consists of a small pool of cells capable of replenishing all blood cells. Although it is established that the hematopoietic system is assembled as a hierarchical organization under steady-state conditions, emerging evidence suggests that distinct differentiation pathways may exist in response to acute stress. However, it remains unclear how different hematopoietic stem and progenitor cell subpopulations behave under sustained chronic stress. Here, by using adult transgenic mice overexpressing erythropoietin (EPO; Tg6) and a combination of in vivo, in vitro, and deep-sequencing approaches, we found that HSCs respond differentially to chronic erythroid stress compared with their closely related multipotent progenitors (MPPs). Specifically, HSCs exhibit a vastly committed erythroid progenitor profile with enhanced cell division, while MPPs display erythroid and myeloid cell signatures and an accumulation of uncommitted cells. Thus, our results identify HSCs as master regulators of chronic stress erythropoiesis, potentially circumventing the hierarchical differentiation-detour.
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22
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Huang X, Trinh T, Aljoufi A, Broxmeyer HE. Hypoxia Signaling Pathway in Stem Cell Regulation: Good and Evil. CURRENT STEM CELL REPORTS 2018; 4:149-157. [PMID: 31275803 DOI: 10.1007/s40778-018-0127-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Purpose of Review This review summarizes the role of hypoxia and hypoxia-inducible factors (HIFs) in the regulation of stem cell biology, specifically focusing on maintenance, differentiation, and stress responses in the context of several stem cell systems. Stem cells for different lineages/tissues reside in distinct niches, and are exposed to diverse oxygen concentrations. Recent studies have revealed the importance of the hypoxia signaling pathway for stem cell functions. Recent Findings Hypoxia and HIFs contribute to maintenance of embryonic stem cells, generation of induced pluripotent stem cells, functionality of hematopoietic stem cells, and survival of leukemia stem cells. Harvest and collection of mouse bone marrow and human cord blood cells in ambient air results in fewer hematopoietic stem cells recovered due to the phenomenon of Extra PHysiologic Oxygen Shock/Stress (EPHOSS). Summary Oxygen is an important factor in the stem cell microenvironment. Hypoxia signaling and HIFs play important roles in modeling cellular metabolism in both stem cells and niches to regulate stem cell biology, and represent an additional dimension that allows stem cells to maintain an undifferentiated status and multilineage differentiation potential.
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Affiliation(s)
- Xinxin Huang
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Thao Trinh
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Arafat Aljoufi
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Hal E Broxmeyer
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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23
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Abstract
Although it is generally believed that oxidative phosphorylation and adequate oxygenation are essential for life, human development occurs in a profoundly hypoxic environment and "normal" levels of oxygen during embryogenesis are even harmful. The ability of embryos not only to survive but also to thrive in such an environment is made possible by adaptations related to metabolic pathways. Similarly, cancerous cells are able not only to survive but also to grow and spread in environments that would typically be fatal for healthy adult cells. Many biological states, both normal and pathological, share underlying similarities related to metabolism, the electron transport chain, and reactive species. The purpose of Part I of this review is to review the similarities among embryogenesis, mammalian adaptions to hypoxia (primarily driven by hypoxia-inducible factor-1), ischemia-reperfusion injury (and its relationship with reactive oxygen species), hibernation, diving animals, cancer, and sepsis, with a particular focus on the common characteristics that allow cells and organisms to survive in these states.
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Affiliation(s)
- Robert H Thiele
- From the Department of Anesthesiology, University of Virginia, Charlottesville, VA
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24
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Guitart AV, Panagopoulou TI, Villacreces A, Vukovic M, Sepulveda C, Allen L, Carter RN, van de Lagemaat LN, Morgan M, Giles P, Sas Z, Gonzalez MV, Lawson H, Paris J, Edwards-Hicks J, Schaak K, Subramani C, Gezer D, Armesilla-Diaz A, Wills J, Easterbrook A, Coman D, So CWE, O'Carroll D, Vernimmen D, Rodrigues NP, Pollard PJ, Morton NM, Finch A, Kranc KR. Fumarate hydratase is a critical metabolic regulator of hematopoietic stem cell functions. J Exp Med 2017; 214:719-735. [PMID: 28202494 PMCID: PMC5339674 DOI: 10.1084/jem.20161087] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 11/29/2016] [Accepted: 01/20/2017] [Indexed: 11/04/2022] Open
Abstract
Strict regulation of stem cell metabolism is essential for tissue functions and tumor suppression. In this study, we investigated the role of fumarate hydratase (Fh1), a key component of the mitochondrial tricarboxylic acid (TCA) cycle and cytosolic fumarate metabolism, in normal and leukemic hematopoiesis. Hematopoiesis-specific Fh1 deletion (resulting in endogenous fumarate accumulation and a genetic TCA cycle block reflected by decreased maximal mitochondrial respiration) caused lethal fetal liver hematopoietic defects and hematopoietic stem cell (HSC) failure. Reexpression of extramitochondrial Fh1 (which normalized fumarate levels but not maximal mitochondrial respiration) rescued these phenotypes, indicating the causal role of cellular fumarate accumulation. However, HSCs lacking mitochondrial Fh1 (which had normal fumarate levels but defective maximal mitochondrial respiration) failed to self-renew and displayed lymphoid differentiation defects. In contrast, leukemia-initiating cells lacking mitochondrial Fh1 efficiently propagated Meis1/Hoxa9-driven leukemia. Thus, we identify novel roles for fumarate metabolism in HSC maintenance and hematopoietic differentiation and reveal a differential requirement for mitochondrial Fh1 in normal hematopoiesis and leukemia propagation.
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Affiliation(s)
- Amelie V Guitart
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Theano I Panagopoulou
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Arnaud Villacreces
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Milica Vukovic
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Catarina Sepulveda
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Lewis Allen
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Roderick N Carter
- Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Louie N van de Lagemaat
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
- The Roslin Institute, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Marcos Morgan
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Peter Giles
- Wales Gene Park and Wales Cancer Research Centre, Division of Cancer and Genetics, School of Medicine, Cardiff University, Cardiff CF10 3XQ, Wales, UK
| | - Zuzanna Sas
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Marta Vila Gonzalez
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Hannah Lawson
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Jasmin Paris
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Joy Edwards-Hicks
- Edinburgh Cancer Research UK Centre, Medical Research Council Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Katrin Schaak
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Chithra Subramani
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Deniz Gezer
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Alejandro Armesilla-Diaz
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Jimi Wills
- Edinburgh Cancer Research UK Centre, Medical Research Council Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Aaron Easterbrook
- Mater Children's Private Hospital Brisbane, South Brisbane, Queensland 4101, Australia
| | - David Coman
- Department of Metabolic Medicine, The Lady Cilento Children's Hospital, South Brisbane, Queensland 4101, Australia
| | - Chi Wai Eric So
- Department of Haematological Medicine, Division of Cancer Studies, King's College London, London WC2R 2LS, England, UK
| | - Donal O'Carroll
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Douglas Vernimmen
- The Roslin Institute, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Neil P Rodrigues
- The European Cancer Stem Cell Research Institute, School of Biosciences, Cardiff University, Cardiff CF10 3XQ, Wales, UK
| | - Patrick J Pollard
- Edinburgh Cancer Research UK Centre, Medical Research Council Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Nicholas M Morton
- Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Andrew Finch
- Edinburgh Cancer Research UK Centre, Medical Research Council Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
| | - Kamil R Kranc
- Medical Research Council Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
- Edinburgh Cancer Research UK Centre, Medical Research Council Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH8 9YL, Scotland, UK
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25
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Rauner M, Franke K, Murray M, Singh RP, Hiram-Bab S, Platzbecker U, Gassmann M, Socolovsky M, Neumann D, Gabet Y, Chavakis T, Hofbauer LC, Wielockx B. Increased EPO Levels Are Associated With Bone Loss in Mice Lacking PHD2 in EPO-Producing Cells. J Bone Miner Res 2016; 31:1877-1887. [PMID: 27082941 DOI: 10.1002/jbmr.2857] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 03/28/2016] [Accepted: 04/12/2016] [Indexed: 12/25/2022]
Abstract
The main oxygen sensor hypoxia inducible factor (HIF) prolyl hydroxylase 2 (PHD2) is a critical regulator of tissue homeostasis during erythropoiesis, hematopoietic stem cell maintenance, and wound healing. Recent studies point toward a role for the PHD2-erythropoietin (EPO) axis in the modulation of bone remodeling, even though the studies produced conflicting results. Here, we used a number of mouse strains deficient of PHD2 in different cell types to address the role of PHD2 and its downstream targets HIF-1α and HIF-2α in bone remodeling. Mice deficient for PHD2 in several cell lineages, including EPO-producing cells, osteoblasts, and hematopoietic cells (CD68:cre-PHD2f/f ) displayed a severe reduction of bone density at the distal femur as well as the vertebral body due to impaired bone formation but not bone resorption. Importantly, using osteoblast-specific (Osx:cre-PHD2f/f ) and osteoclast-specific PHD2 knock-out mice (Vav:cre- PHD2f/f ), we show that this effect is independent of the loss of PHD2 in osteoblast and osteoclasts. Using different in vivo and in vitro approaches, we show here that this bone phenotype, including the suppression of bone formation, is directly linked to the stabilization of the α-subunit of HIF-2, and possibly to the subsequent moderate induction of serum EPO, which directly influenced the differentiation and mineralization of osteoblast progenitors resulting in lower bone density. Taken together, our data identify the PHD2:HIF-2α:EPO axis as a so far unknown regulator of osteohematology by controlling bone homeostasis. Further, these data suggest that patients treated with PHD inhibitors or EPO should be monitored with respect to their bone status. © 2016 American Society for Bone and Mineral Research.
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Affiliation(s)
- Martina Rauner
- Department of Medicine III, Technische Universität Dresden, Dresden, Germany
| | - Kristin Franke
- Department of Clinical Pathobiochemistry, Technische Universität Dresden, Dresden, Germany.,Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany
| | - Marta Murray
- Department of Clinical Pathobiochemistry, Technische Universität Dresden, Dresden, Germany.,Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany
| | - Rashim Pal Singh
- Department of Clinical Pathobiochemistry, Technische Universität Dresden, Dresden, Germany.,Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany
| | - Sahar Hiram-Bab
- Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Uwe Platzbecker
- Department of Medicine I, Technische Universität Dresden, Dresden, Germany
| | - Max Gassmann
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zürich, Zürich, Switzerland.,Zurich Center for Integrative Human Physiology (ZIHP), University of Zürich, Zürich, Switzerland.,Universidad Peruana Cayetano Heredia (UPCH), Lima, Peru
| | - Merav Socolovsky
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA.,Department of Pediatrics, University of Massachusetts Medical School, Worcester, MA
| | - Drorit Neumann
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Yankel Gabet
- Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Triantafyllos Chavakis
- Department of Clinical Pathobiochemistry, Technische Universität Dresden, Dresden, Germany.,Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany.,Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Lorenz C Hofbauer
- Department of Medicine III, Technische Universität Dresden, Dresden, Germany.,Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Ben Wielockx
- Department of Clinical Pathobiochemistry, Technische Universität Dresden, Dresden, Germany. .,Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany. .,Center for Regenerative Therapies Dresden, Dresden, Germany.
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26
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Abstract
Oxygen represents one of the major molecules required for the development and maintenance of life. An adequate response to hypoxia is therefore required for the functioning of the majority of living organisms and relies on the activation of the hypoxia-inducible factor (HIF) pathway. HIF prolyl hydroxylase domain-2 (PHD2) has long been recognized as the major regulator of this response, controlling a myriad of outcomes that range from cell death to proliferation. However, this enzyme has been associated with more pathways, making the role of this protein remarkably complex under distinct pathologies. While a protective role seems to exist in physiological conditions such as erythropoiesis; the picture is more complex during pathologies such as cancer. Since the regulation of this enzyme and its closest family members is currently considered as a possible therapy for various diseases, understanding the different particular roles of this protein is essential.
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Affiliation(s)
- Ana M Meneses
- Heisenberg Research Group, Department of Clinical Pathobiochemistry, Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany
| | - Ben Wielockx
- Heisenberg Research Group, Department of Clinical Pathobiochemistry, Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Dresden, Germany
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27
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Cheng S, Xing W, Pourteymoor S, Schulte J, Mohan S. Conditional Deletion of Prolyl Hydroxylase Domain-Containing Protein 2 (Phd2) Gene Reveals Its Essential Role in Chondrocyte Function and Endochondral Bone Formation. Endocrinology 2016; 157:127-40. [PMID: 26562260 PMCID: PMC4701886 DOI: 10.1210/en.2015-1473] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The hypoxic growth plate cartilage requires hypoxia-inducible factor (HIF)-mediated pathways to maintain chondrocyte survival and differentiation. HIF proteins are tightly regulated by prolyl hydroxylase domain-containing protein 2 (Phd2)-mediated proteosomal degradation. We conditionally disrupted the Phd2 gene in chondrocytes by crossing Phd2 floxed mice with type 2 collagen-α1-Cre transgenic mice and found massive increases (>50%) in the trabecular bone mass of long bones and lumbar vertebra of the Phd2 conditional knockout (cKO) mice caused by significant increases in trabecular number and thickness and reductions in trabecular separation. Cortical thickness and tissue mineral density at the femoral middiaphysis of the cKO mice were also significantly increased. Dynamic histomorphometric analyses revealed increased longitudinal length and osteoid surface per bone surface in the primary spongiosa of the cKO mice, suggesting elevated conversion rate from hypertrophic chondrocytes to mineralized bone matrix as well as increased bone formation in the primary spongiosa. In the secondary spongiosa, bone formation measured by mineralizing surface per bone surface and mineral apposition rate were not changed, but resorption was slightly reduced. Increases in the mRNA levels of SRY (sex determining region Y)-box 9, osterix (Osx), type 2 collagen, aggrecan, alkaline phosphatase, bone sialoprotein, vascular endothelial growth factor, erythropoietin, and glycolytic enzymes in the growth plate of cKO mice were detected by quantitative RT-PCR. Immunohistochemistry revealed an increased HIF-1α protein level in the hypertrophic chondrocytes of cKO mice. Infection of chondrocytes isolated from Phd2 floxed mice with adenoviral Cre resulted in similar gene expression patterns as observed in the cKO growth plate chondrocytes. Our findings indicate that Phd2 suppresses endochondral bone formation, in part, via HIF-dependent mechanisms in mice.
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Affiliation(s)
- Shaohong Cheng
- Musculoskeletal Disease Center (S.C., W.X., S.P., J.S., S.M.), Jerry L. Pettis Veterans Affairs Medical Center, Loma Linda, California 92357; and Department of Medicine (W.X., S.M.), Loma Linda University, Loma Linda, California 92354
| | - Weirong Xing
- Musculoskeletal Disease Center (S.C., W.X., S.P., J.S., S.M.), Jerry L. Pettis Veterans Affairs Medical Center, Loma Linda, California 92357; and Department of Medicine (W.X., S.M.), Loma Linda University, Loma Linda, California 92354
| | - Sheila Pourteymoor
- Musculoskeletal Disease Center (S.C., W.X., S.P., J.S., S.M.), Jerry L. Pettis Veterans Affairs Medical Center, Loma Linda, California 92357; and Department of Medicine (W.X., S.M.), Loma Linda University, Loma Linda, California 92354
| | - Jan Schulte
- Musculoskeletal Disease Center (S.C., W.X., S.P., J.S., S.M.), Jerry L. Pettis Veterans Affairs Medical Center, Loma Linda, California 92357; and Department of Medicine (W.X., S.M.), Loma Linda University, Loma Linda, California 92354
| | - Subburaman Mohan
- Musculoskeletal Disease Center (S.C., W.X., S.P., J.S., S.M.), Jerry L. Pettis Veterans Affairs Medical Center, Loma Linda, California 92357; and Department of Medicine (W.X., S.M.), Loma Linda University, Loma Linda, California 92354
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28
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Yang M, Su H, Soga T, Kranc KR, Pollard PJ. Prolyl hydroxylase domain enzymes: important regulators of cancer metabolism. HYPOXIA 2014; 2:127-142. [PMID: 27774472 PMCID: PMC5045062 DOI: 10.2147/hp.s47968] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The hypoxia-inducible factor (HIF) prolyl hydroxylase domain enzymes (PHDs) regulate the stability of HIF protein by post-translational hydroxylation of two conserved prolyl residues in its α subunit in an oxygen-dependent manner. Trans-4-prolyl hydroxylation of HIFα under normal oxygen (O2) availability enables its association with the von Hippel-Lindau (VHL) tumor suppressor pVHL E3 ligase complex, leading to the degradation of HIFα via the ubiquitin-proteasome pathway. Due to the obligatory requirement of molecular O2 as a co-substrate, the activity of PHDs is inhibited under hypoxic conditions, resulting in stabilized HIFα, which dimerizes with HIFβ and, together with transcriptional co-activators CBP/p300, activates the transcription of its target genes. As a key molecular regulator of adaptive response to hypoxia, HIF plays important roles in multiple cellular processes and its overexpression has been detected in various cancers. The HIF1α isoform in particular has a strong impact on cellular metabolism, most notably by promoting anaerobic, whilst inhibiting O2-dependent, metabolism of glucose. The PHD enzymes also seem to have HIF-independent functions and are subject to regulation by factors other than O2, such as by metabolic status, oxidative stress, and abnormal levels of endogenous metabolites (oncometabolites) that have been observed in some types of cancers. In this review, we aim to summarize current understandings of the function and regulation of PHDs in cancer with an emphasis on their roles in metabolism.
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Affiliation(s)
- Ming Yang
- Cancer Biology and Metabolism Group, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Huizhong Su
- Cancer Biology and Metabolism Group, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Tomoyoshi Soga
- Institute for Advanced Biosciences, Keio University, Mizukami, Tsuruoka, Yamagata, Japan
| | - Kamil R Kranc
- MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK
| | - Patrick J Pollard
- Cancer Biology and Metabolism Group, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
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29
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Gardie B, Percy MJ, Hoogewijs D, Chowdhury R, Bento C, Arsenault PR, Richard S, Almeida H, Ewing J, Lambert F, McMullin MF, Schofield CJ, Lee FS. The role of PHD2 mutations in the pathogenesis of erythrocytosis. HYPOXIA 2014; 2:71-90. [PMID: 27774468 PMCID: PMC5045058 DOI: 10.2147/hp.s54455] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The transcription of the erythropoietin (EPO) gene is tightly regulated by the hypoxia response pathway to maintain oxygen homeostasis. Elevations in serum EPO level may be reflected in an augmentation in the red cell mass, thereby causing erythrocytosis. Studies on erythrocytosis have provided insights into the function of the oxygen-sensing pathway and the critical proteins involved in the regulation of EPO transcription. The α subunits of the hypoxia-inducible transcription factor are hydroxylated by three prolyl hydroxylase domain (PHD) enzymes, which belong to the iron and 2-oxoglutarate-dependent oxygenase superfamily. Sequence analysis of the genes encoding the PHDs in patients with erythrocytosis has revealed heterozygous germline mutations only occurring in Egl nine homolog 1 (EGLN1, also known as PHD2), the gene that encodes PHD2. To date, 24 different EGLN1 mutations comprising missense, frameshift, and nonsense mutations have been described. The phenotypes associated with the patients carrying these mutations are fairly homogeneous and typically limited to erythrocytosis with normal to elevated EPO. However, exceptions exist; for example, there is one case with development of concurrent paraganglioma (PHD2-H374R). Analysis of the erythrocytosis-associated PHD2 missense mutations has shown heterogeneous results. Structural studies reveal that mutations can affect different domains of PHD2. Some are close to the hypoxia-inducible transcription factor α/2-oxoglutarate or the iron binding sites for PHD2. In silico studies demonstrate that the mutations do not always affect fully conserved residues. In vitro and in cellulo studies showed varying effects of the mutations, ranging from mild effects to severe loss of function. The exact mechanism of a potential tumor-suppressor role for PHD2 still needs to be elucidated. A knockin mouse model expressing the first reported PHD2-P317R mutation recapitulates the phenotype observed in humans (erythrocytosis with inappropriately normal serum EPO levels) and demonstrates that haploinsufficiency and partial deregulation of PHD2 is sufficient to cause erythrocytosis.
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Affiliation(s)
- Betty Gardie
- Laboratoire de Génétique Oncologique de l'Ecole Pratique des Hautes Etudes, Villejuif; Unité Mixte de Recherche, Institut national de la santé et de la recherche médicale U892, Centre national de la recherche scientifique 6299, Centre de Recherche en Cancérologie Nantes/Angers, Université de Nantes, Nantes, France
| | - Melanie J Percy
- Department of Haematology, Belfast City Hospital, Belfast, UK
| | - David Hoogewijs
- Institute of Physiology and Zürich Center for Integrative Human Physiology, University of Zürich, Zürich, Switzerland
| | - Rasheduzzaman Chowdhury
- Department of Chemistry and Oxford Centre for Integrative Systems Biology, Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - Celeste Bento
- Department of Hematology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - Patrick R Arsenault
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Stéphane Richard
- Laboratoire de Génétique Oncologique de l'Ecole Pratique des Hautes Etudes, Villejuif; Institut national de la santé et de la recherche médicale U753, Institut de cancérologie Gustave Roussy (IGR), Villejuif, France; Faculté de Médecine Paris-Sud, Le Kremlin-Bicêtre, France
| | - Helena Almeida
- Department of Hematology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | | | - Frédéric Lambert
- Center for Human Genetics, Pathology Institute, UniLab-Lg, Molecular Haemato-Oncology Unit, CHU of Liege, Liege, Belgium
| | | | - Christopher J Schofield
- Department of Chemistry and Oxford Centre for Integrative Systems Biology, Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - Frank S Lee
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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30
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Gezer D, Vukovic M, Soga T, Pollard PJ, Kranc KR. Concise review: genetic dissection of hypoxia signaling pathways in normal and leukemic stem cells. Stem Cells 2014; 32:1390-7. [PMID: 24496882 DOI: 10.1002/stem.1657] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 12/21/2013] [Indexed: 02/11/2024]
Abstract
Adult hematopoiesis depends on rare multipotent hematopoietic stem cells (HSCs) that self-renew and give rise to progenitor cells, which differentiate to all blood lineages. The strict regulation of the fine balance between self-renewal and differentiation is essential for normal hematopoiesis and suppression of leukemia development. HSCs and progenitor cells are commonly assumed to reside within the hypoxic BM microenvironment, however, there is no direct evidence supporting this notion. Nevertheless, HSCs and progenitors do exhibit a hypoxic profile and strongly express Hif-1α. Although hypoxia signaling pathways are thought to play important roles in adult HSC maintenance and leukemogenesis, the precise function of Hif-dependent signaling in HSCs remains to be uncovered. Here we discuss recent gain-of-function and loss-of-function studies that shed light on the complex roles of hypoxia-signaling pathways in HSCs and their niches in normal and malignant hematopoiesis. Importantly, we comment on the current and often contrasting interpretations of the role of Hif-dependent signaling in stem cell functions.
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Affiliation(s)
- Deniz Gezer
- MRC Centre for Regenerative Medicine. University of Edinburgh, Edinburgh, United Kingdom; Paul O'Gorman Leukaemia Research Centre, University of Glasgow, Glasgow, United Kingdom; 3Klinik fuer Haematologie, Onkologie und Stammzelltransplantation, Universitaetsklinikum Aachen, Aachen, Germany
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31
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Vicha A, Taieb D, Pacak K. Current views on cell metabolism in SDHx-related pheochromocytoma and paraganglioma. Endocr Relat Cancer 2014; 21:R261-77. [PMID: 24500761 PMCID: PMC4016161 DOI: 10.1530/erc-13-0398] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Warburg's metabolic hypothesis is based on the assumption that a cancer cell's respiration must be under attack, leading to its damage, in order to obtain increased glycolysis. Although this may not apply to all cancers, there is some evidence proving that primarily abnormally functioning mitochondrial complexes are indeed related to cancer development. Thus, mutations in complex II (succinate dehydrogenase (SDH)) lead to the formation of pheochromocytoma (PHEO)/paraganglioma (PGL). Mutations in one of the SDH genes (SDHx mutations) lead to succinate accumulation associated with very low fumarate levels, increased glutaminolysis, the generation of reactive oxygen species, and pseudohypoxia. This results in significant changes in signaling pathways (many of them dependent on the stabilization of hypoxia-inducible factor), including oxidative phosphorylation, glycolysis, specific expression profiles, as well as genomic instability and increased mutability resulting in tumor development. Although there is currently no very effective therapy for SDHx-related metastatic PHEOs/PGLs, targeting their fundamental metabolic abnormalities may provide a unique opportunity for the development of novel and more effective forms of therapy for these tumors.
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Affiliation(s)
- Ales Vicha
- Department of Pediatric Hematology and Oncology, 2 Medical School, Charles University and University Hospital Motol, Prague, Czech Republic
| | - David Taieb
- Service Central de Biophysique et de Médecine Nucléaire, CERIMED Centre hospitalo-universitaire Timone, Marseille, France
- Département d’Oncologie Moléculaire, Centre de Recherche en Cancérologie de Marseille, Marseille, France
| | - Karel Pacak
- Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD), National Institutes of Health, Bethesda, Maryland, 20892 USA
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Forristal CE, Levesque JP. Targeting the hypoxia-sensing pathway in clinical hematology. Stem Cells Transl Med 2013; 3:135-40. [PMID: 24371328 DOI: 10.5966/sctm.2013-0134] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Hypoxia-inducible factors (HIFs) are oxygen-sensitive transcription factors regulated by oxygen-dependent prolyl hydroxylase domain (PHD) enzymes and are key to cell adaptation to low oxygen. The hematopoietic stem cell (HSC) niche in the bone marrow is highly heterogeneous in terms of microvasculature and thus oxygen concentration. The importance of hypoxia and HIFs in the hematopoietic environment is becoming increasingly recognized. Many small compounds that inhibit PHDs have been developed, enabling HIFs to be pharmacologically stabilized in an oxygen-independent manner. The use of PHD inhibitors for therapeutic intervention in hematopoiesis is being increasingly investigated. PHD inhibitors are well established to increase erythropoietin production to correct anemia in hemodialysis patients. Pharmacological stabilization of HIF-1α protein with PHD inhibitors is also emerging as an important regulator of HSC proliferation and self-renewal. Administration of PHD inhibitors increases quiescence and decreases proliferation of HSCs in the bone marrow in vivo, thereby protecting them from high doses of irradiation and accelerating hematological recovery. Recent findings also show that stabilization of HIF-1α increases mobilization of HSCs in response to granulocyte colony-stimulating factor and plerixafor, suggesting that PHD inhibitors could be useful agents to increase mobilization success in patients requiring transplantation. These findings highlight the importance of the hypoxia-sensing pathway and HIFs in clinical hematology.
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Affiliation(s)
- Catherine E Forristal
- Stem Cell Biology Group, Mater Research Institute-University of Queensland, Woolloongabba, Queensland, Australia
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Arsenault PR, Pei F, Lee R, Kerestes H, Percy MJ, Keith B, Simon MC, Lappin TRJ, Khurana TS, Lee FS. A knock-in mouse model of human PHD2 gene-associated erythrocytosis establishes a haploinsufficiency mechanism. J Biol Chem 2013; 288:33571-33584. [PMID: 24121508 DOI: 10.1074/jbc.m113.482364] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The central pathway for controlling red cell mass is the PHD (prolyl hydroxylase domain protein):hypoxia-inducible factor (HIF) pathway. HIF, which is negatively regulated by PHD, activates numerous genes, including ones involved in erythropoiesis, such as the ERYTHROPOIETIN (EPO) gene. Recent studies have implicated PHD2 as the key PHD isoform regulating red cell mass. Studies of humans have identified erythrocytosis-associated, heterozygous point mutations in the PHD2 gene. A key question concerns the mechanism by which human mutations lead to phenotypes. In the present report, we generated and characterized a mouse line in which a P294R knock-in mutation has been introduced into the mouse Phd2 locus to model the first reported human PHD2 mutation (P317R). Phd2(P294R/+) mice display a degree of erythrocytosis equivalent to that seen in Phd2(+/-) mice. The Phd2(P294R/+)-associated erythrocytosis is reversed in a Hif2a(+/-), but not a Hif1a(+/-) background. Additional studies using various conditional knock-outs of Phd2 reveal that erythrocytosis can be induced by homozygous and heterozygous knock-out of Phd2 in renal cortical interstitial cells using a Pax3-Cre transgene or by homozygous knock-out of Phd2 in hematopoietic progenitors driven by a Vav1-Cre transgene. These studies formally prove that a missense mutation in PHD2 is the cause of the erythrocytosis, show that this occurs through haploinsufficiency, and point to multifactorial control of red cell mass by PHD2.
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Affiliation(s)
- Patrick R Arsenault
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Fei Pei
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Rebecca Lee
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Heddy Kerestes
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Melanie J Percy
- Department of Haematology, Belfast City Hospital, Belfast, Northern Ireland BT9 7AB, United Kingdom
| | - Brian Keith
- Department of Cancer Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104; Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - M Celeste Simon
- Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104; Department of Cell and Developmental Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104; Howard Hughes Medical Institute, Philadelphia, Pennsylvania 19104
| | - Terence R J Lappin
- Centre for Cancer Research and Cell Biology, Queen's University, Belfast, Northern Ireland BT9 7BL, United Kingdom
| | - Tejvir S Khurana
- Department of Physiology and Pennsylvania Muscle Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Frank S Lee
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
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Mamlouk S, Kalucka J, Singh RP, Franke K, Muschter A, Langer A, Jakob C, Gassmann M, Baretton GB, Wielockx B. Loss of prolyl hydroxylase-2 in myeloid cells and T-lymphocytes impairs tumor development. Int J Cancer 2013; 134:849-58. [DOI: 10.1002/ijc.28409] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 06/14/2013] [Accepted: 07/16/2013] [Indexed: 12/20/2022]
Affiliation(s)
- Soulafa Mamlouk
- Emmy Noether Research Group; University of Technology; Dresden Germany
- Institute of Pathology; University of Technology Dresden; Dresden Germany
| | - Joanna Kalucka
- Emmy Noether Research Group; University of Technology; Dresden Germany
- Institute of Pathology; University of Technology Dresden; Dresden Germany
| | - Rashim Pal Singh
- Emmy Noether Research Group; University of Technology; Dresden Germany
- Institute of Pathology; University of Technology Dresden; Dresden Germany
| | - Kristin Franke
- Emmy Noether Research Group; University of Technology; Dresden Germany
- Institute of Pathology; University of Technology Dresden; Dresden Germany
| | - Antje Muschter
- Emmy Noether Research Group; University of Technology; Dresden Germany
- Institute of Pathology; University of Technology Dresden; Dresden Germany
| | - Anika Langer
- Emmy Noether Research Group; University of Technology; Dresden Germany
- Institute of Pathology; University of Technology Dresden; Dresden Germany
| | - Christiane Jakob
- Institute of Pathology; University of Technology Dresden; Dresden Germany
| | - Max Gassmann
- Institute of Veterinary Physiology, Vetsuisse Faculty and Zurich Center for Integrative Human Physiology (ZIHP); University of Zürich; Zürich Switzerland
- Universidad Peruana Cayetano Heredia (UPCH); Lima Peru
| | | | - Ben Wielockx
- Emmy Noether Research Group; University of Technology; Dresden Germany
- Institute of Pathology; University of Technology Dresden; Dresden Germany
- DFG Research Center and Cluster of Excellence for Regenerative Therapies Dresden; University of Technology Dresden; Dresden Germany
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Loss of epithelial hypoxia-inducible factor prolyl hydroxylase 2 accelerates skin wound healing in mice. Mol Cell Biol 2013; 33:3426-38. [PMID: 23798557 DOI: 10.1128/mcb.00609-13] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Skin wound healing in mammals is a complex, multicellular process that depends on the precise supply of oxygen. Hypoxia-inducible factor (HIF) prolyl hydroxylase 2 (PHD2) serves as a crucial oxygen sensor and may therefore play an important role during reepithelialization. Hence, this study was aimed at understanding the role of PHD2 in cutaneous wound healing using different lines of conditionally deficient mice specifically lacking PHD2 in inflammatory, vascular, or epidermal cells. Interestingly, PHD2 deficiency only in keratinocytes and not in myeloid or endothelial cells was found to lead to faster wound closure, which involved enhanced migration of the hyperproliferating epithelium. We demonstrate that this effect relies on the unique expression of β3-integrin in the keratinocytes around the tip of the migrating tongue in an HIF1α-dependent manner. Furthermore, we show enhanced proliferation of these cells in the stratum basale, which is directly related to their attenuated transforming growth factor β signaling. Thus, loss of the central oxygen sensor PHD2 in keratinocytes stimulates wound closure by prompting skin epithelial cells to migrate and proliferate. Inhibition of PHD2 could therefore offer novel therapeutic opportunities for the local treatment of cutaneous wounds.
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