1
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Silva AFB, Lima LF, Ferreira ACA, Oliveira AC, Neto NMA, Alves BG, Rodrigues APR, Gastal EL, Bordignon V, Figueiredo JR. Improving survival and growth of caprine preantral follicles cultured in medium commonly used for MSC: Role of oxidative stress regulation and epigenetic changes. Domest Anim Endocrinol 2024; 90:106890. [PMID: 39366130 DOI: 10.1016/j.domaniend.2024.106890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2024] [Revised: 09/14/2024] [Accepted: 09/18/2024] [Indexed: 10/06/2024]
Abstract
This study evaluated the efficiency of in vitro culture of preantral follicles (PAF) in a commonly used medium for mesenchymal stem cell (MSC) culture. Parameters assessed included follicle survival, growth, stromal cell density, levels of reduced thiols and reactive oxygen species, epigenetic changes, cell apoptosis, and mRNA abundance. Caprine ovarian tissues were cultured for 1 or 7 days in either PAF or MSC-common media, with uncultured tissues serving as controls. The MSC medium exhibited increased follicular survival and growth and remodeled stromal density potentially through the regulation of oxidative stress and epigenetic changes compared to the PAF medium. In conclusion, our results highlight the importance of the MSC medium in enhancing follicular survival and growth, changing the stromal cell density, as well as in regulating the medium oxidative stress and epigenetic changes during the in vitro culture of caprine PAF.
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Affiliation(s)
- Ana F B Silva
- Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil
| | - Laritza F Lima
- Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil
| | - Anna C A Ferreira
- Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil
| | - Ariclécio C Oliveira
- Superior Institute of Biomedical Science, State University of Ceará, Fortaleza, CE, Brazil
| | - Napoleão M A Neto
- Integrated Nucleus of Morphology and Research with Stem Cells, Federal University of Piauí, Teresina, PI, Brazil
| | | | - Ana P R Rodrigues
- Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil
| | - Eduardo L Gastal
- Animal Science, School of Agricultural Sciences, Southern Illinois University, Carbondale, IL, USA.
| | - Vilceu Bordignon
- Department of Animal Science, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada
| | - José R Figueiredo
- Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil.
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2
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Ali A, Azmat U, Ji Z, Khatoon A, Murtaza B, Akbar K, Irshad U, Raza R, Su Z. Beyond Genes: Epiregulomes as Molecular Commanders in Innate Immunity. Int Immunopharmacol 2024; 142:113149. [PMID: 39278059 DOI: 10.1016/j.intimp.2024.113149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2024] [Revised: 08/09/2024] [Accepted: 09/08/2024] [Indexed: 09/17/2024]
Abstract
The natural fastest way to deal with pathogens or danger signals is the innate immune system. This system prevents too much inflammation and tissue damage and efficiently eliminates pathogens. The epiregulome is the chromatin structure influenced by epigenetic factors and linked to cis-regulatory elements (CREs). The epiregulome helps to end the inflammatory response and also assists innate immune cells to show specific action by making cell-specific gene expression patterns. This inspection unfolds two concepts: (1) how epiregulomes are shaped by switching the expression levels of genes, manoeuvre enzyme activity and earmark of chromatin modifiers on specific genes; during and after the infection, and (2) how the expression of specific genes (aids in prompt management of innate cell growth, or the reaction to aggravation and illness) command by epiregulomes that formed during the above process. In this review, the consequences of intrinsic immuno-metabolic remodelling on epiregulomes and potential difficulties in identifying the master epiregulome that regulates innate immunity and inflammation have been discussed.
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Affiliation(s)
- Ashiq Ali
- Department of Histology and Embryology, Shantou University Medical College, China.
| | - Urooj Azmat
- Department of Zoology, Wildlife and Fisheries, University of Agriculture, Faisalabad, Pakistan
| | - Ziyi Ji
- Department of Histology and Embryology, Shantou University Medical College, China
| | - Aisha Khatoon
- Department of Pathology, University of Agriculture Faisalabad, Pakistan
| | - Bilal Murtaza
- School of Bioengineering, Dalian University of Science and Technology, Dalian, China
| | - Kaynaat Akbar
- Department of Zoology, Wildlife and Fisheries, University of Agriculture, Faisalabad, Pakistan
| | - Urooj Irshad
- Department Biological Sciences, Faculty of Sciences, Superior University Lahore, Punjab, Pakistan
| | - Rameen Raza
- Department of Pathology, University of Agriculture Faisalabad, Pakistan
| | - Zhongjing Su
- Department of Histology and Embryology, Shantou University Medical College, China.
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3
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Ortmann BM, Taylor CT, Rocha S. Hypoxia research, where to now? Trends Biochem Sci 2024; 49:573-582. [PMID: 38599898 DOI: 10.1016/j.tibs.2024.03.008] [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: 12/13/2023] [Revised: 03/01/2024] [Accepted: 03/18/2024] [Indexed: 04/12/2024]
Abstract
Investigating how cells and organisms sense and respond to O2 levels is essential to our understanding of physiology and pathology. This field has advanced considerably since the discovery of the major transcription factor family, hypoxia-inducible factor (HIF), and the enzymes that control its levels: prolyl hydroxylases (PHDs). However, with its expansion, new complexities have emerged. Herein we highlight three main areas where, in our opinion, the research community could direct some of their attention. These include non-transcriptional roles of HIFs, specificity and O2 sensitivity of 2-oxoglutarate-dependent dioxygenases (2-OGDDs), and new tools and methods to detect O2 concentrations in cells and organs. A greater understanding of these areas would answer big questions and help drive our knowledge of cellular responses to hypoxia forward.
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Affiliation(s)
- Brian M Ortmann
- Wolfson Childhood Cancer Research Centre, Newcastle University, Newcastle upon Tyne, UK.
| | - Cormac T Taylor
- School of Medicine and Medical Sciences, University College Dublin, Dublin, Ireland.
| | - Sonia Rocha
- Institute of Systems Molecular and Integrative Biology, University of Liverpool, Liverpool, UK.
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4
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Batie M, Fasanya T, Kenneth NS, Rocha S. Oxygen-regulated post-translation modifications as master signalling pathway in cells. EMBO Rep 2023; 24:e57849. [PMID: 37877678 DOI: 10.15252/embr.202357849] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 09/22/2023] [Accepted: 10/12/2023] [Indexed: 10/26/2023] Open
Abstract
Oxygen is essential for viability in mammalian organisms. However, cells are often exposed to changes in oxygen availability, due to either increased demand or reduced oxygen supply, herein called hypoxia. To be able to survive and/or adapt to hypoxia, cells activate a variety of signalling cascades resulting in changes to chromatin, gene expression, metabolism and viability. Cellular signalling is often mediated via post-translational modifications (PTMs), and this is no different in response to hypoxia. Many enzymes require oxygen for their activity and oxygen can directly influence several PTMS. Here, we review the direct impact of changes in oxygen availability on PTMs such as proline, asparagine, histidine and lysine hydroxylation, lysine and arginine methylation and cysteine dioxygenation, with a focus on mammalian systems. In addition, indirect hypoxia-dependent effects on phosphorylation, ubiquitination and sumoylation will also be discussed. Direct and indirect oxygen-regulated changes to PTMs are coordinated to achieve the cell's ultimate response to hypoxia. However, specific oxygen sensitivity and the functional relevance of some of the identified PTMs still require significant research.
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Affiliation(s)
- Michael Batie
- Department of Biochemistry, Cell and Systems Biology, Institute of Molecular Systems and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Temitope Fasanya
- Department of Biochemistry, Cell and Systems Biology, Institute of Molecular Systems and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Niall S Kenneth
- Department of Biochemistry, Cell and Systems Biology, Institute of Molecular Systems and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Sonia Rocha
- Department of Biochemistry, Cell and Systems Biology, Institute of Molecular Systems and Integrative Biology, University of Liverpool, Liverpool, UK
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5
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Suganuma T, Workman JL. Chromatin balances cell redox and energy homeostasis. Epigenetics Chromatin 2023; 16:46. [PMID: 38017471 PMCID: PMC10683155 DOI: 10.1186/s13072-023-00520-8] [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: 08/16/2023] [Accepted: 10/30/2023] [Indexed: 11/30/2023] Open
Abstract
Chromatin plays a central role in the conversion of energy in cells: alteration of chromatin structure to make DNA accessible consumes energy, and compaction of chromatin preserves energy. Alteration of chromatin structure uses energy sources derived from carbon metabolism such as ATP and acetyl-CoA; conversely, chromatin compaction and epigenetic modification feedback to metabolism and energy homeostasis by controlling gene expression and storing metabolites. Coordination of these dual chromatin events must be flexibly modulated in response to environmental changes such as during development and exposure to stress. Aging also alters chromatin structure and the coordination of metabolism, chromatin dynamics, and other cell processes. Noncoding RNAs and other RNA species that associate directly with chromatin or with chromatin modifiers contribute to spatiotemporal control of transcription and energy conversion. The time required for generating the large amounts of RNAs and chromatin modifiers observed in super-enhancers may be critical for regulation of transcription and may be impacted by aging. Here, taking into account these factors, we review alterations of chromatin that are fundamental to cell responses to metabolic changes due to stress and aging to maintain redox and energy homeostasis. We discuss the relationship between spatiotemporal control of energy and chromatin function, as this emerging concept must be considered to understand how cell homeostasis is maintained.
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Affiliation(s)
- Tamaki Suganuma
- Stowers Institute for Medical Research, 1000 E. 50th Street, Kansas City, MO, 64110, USA.
| | - Jerry L Workman
- Stowers Institute for Medical Research, 1000 E. 50th Street, Kansas City, MO, 64110, USA
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6
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Huang Y, Ping X, Cui Y, Yang H, Bao J, Yin Q, Ailifeire H, Shentu X. Glycolysis Aids in Human Lens Epithelial Cells' Adaptation to Hypoxia. Antioxidants (Basel) 2023; 12:1304. [PMID: 37372033 PMCID: PMC10295312 DOI: 10.3390/antiox12061304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 05/30/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
Hypoxic environments are known to trigger pathological damage in multiple cellular subtypes. Interestingly, the lens is a naturally hypoxic tissue, with glycolysis serving as its main source of energy. Hypoxia is essential for maintaining the long-term transparency of the lens in addition to avoiding nuclear cataracts. Herein, we explore the complex mechanisms by which lens epithelial cells adapt to hypoxic conditions while maintaining their normal growth and metabolic activity. Our data show that the glycolysis pathway is significantly upregulated during human lens epithelial (HLE) cells exposure to hypoxia. The inhibition of glycolysis under hypoxic conditions incited endoplasmic reticulum (ER) stress and reactive oxygen species (ROS) production in HLE cells, leading to cellular apoptosis. After ATP was replenished, the damage to the cells was not completely recovered, and ER stress, ROS production, and cell apoptosis still occurred. These results suggest that glycolysis not only performs energy metabolism in the process of HLE cells adapting to hypoxia, but also helps them continuously resist cell apoptosis caused by ER stress and ROS production. Furthermore, our proteomic atlas provides possible rescue mechanisms for cellular damage caused by hypoxia.
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Affiliation(s)
| | | | | | | | | | | | | | - Xingchao Shentu
- Eye Center, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Zhejiang Provincial Key Laboratory of Ophthalmology, Zhejiang Provincial Clinical Research Center for Eye Diseases, Zhejiang Provincial Engineering Institute on Eye Diseases, Hangzhou 310009, China
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7
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Collier H, Albanese A, Kwok CS, Kou J, Rocha S. Functional crosstalk between chromatin and hypoxia signalling. Cell Signal 2023; 106:110660. [PMID: 36990334 DOI: 10.1016/j.cellsig.2023.110660] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/18/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023]
Abstract
Eukaryotic genomes are organised in a structure called chromatin, comprising of DNA and histone proteins. Chromatin is thus a fundamental regulator of gene expression, as it offers storage and protection but also controls accessibility to DNA. Sensing and responding to reductions in oxygen availability (hypoxia) have recognised importance in both physiological and pathological processes in multicellular organisms. One of the main mechanisms controlling these responses is control of gene expression. Recent findings in the field of hypoxia have highlighted how oxygen and chromatin are intricately linked. This review will focus on mechanisms controlling chromatin in hypoxia, including chromatin regulators such as histone modifications and chromatin remodellers. It will also highlight how these are integrated with hypoxia inducible factors and the knowledge gaps that persist.
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Affiliation(s)
- Harry Collier
- Institute of Systems Molecular and Integrative Biology, University of Liverpool, United Kingdom
| | - Adam Albanese
- Institute of Systems Molecular and Integrative Biology, University of Liverpool, United Kingdom
| | - Chun-Sui Kwok
- Institute of Systems Molecular and Integrative Biology, University of Liverpool, United Kingdom
| | - Jiahua Kou
- Institute of Systems Molecular and Integrative Biology, University of Liverpool, United Kingdom
| | - Sonia Rocha
- Institute of Systems Molecular and Integrative Biology, University of Liverpool, United Kingdom.
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8
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Morrison T, Watts ER, Sadiku P, Walmsley SR. The emerging role for metabolism in fueling neutrophilic inflammation. Immunol Rev 2023; 314:427-441. [PMID: 36326284 PMCID: PMC10953397 DOI: 10.1111/imr.13157] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Neutrophils are a critical element of host defense and are rapidly recruited to inflammatory sites. Such sites are frequently limited in oxygen and/or nutrient availability, presenting a metabolic challenge for infiltrating cells. Long believed to be uniquely dependent on glycolysis, it is now clear that neutrophils possess far greater metabolic plasticity than previously thought, with the capacity to generate energy stores and utilize extracellular proteins to fuel central carbon metabolism and biosynthetic activity. Out-with cellular energetics, metabolic programs have also been implicated in the production of neutrophils and their progenitors in the bone marrow compartment, activation of neutrophil antimicrobial responses, inflammatory and cell survival signaling cascades, and training of the innate immune response. Thus, understanding the mechanisms by which metabolic processes sustain changes in neutrophil effector functions and how these are subverted in disease states provides exciting new avenues for the treatment of dysfunctional neutrophilic inflammation which are lacking in clinical practice to date.
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Affiliation(s)
- Tyler Morrison
- University of Edinburgh Centre for Inflammation Research, Queen's Medical Research Institute, University of EdinburghEdinburghUK
| | - Emily R. Watts
- University of Edinburgh Centre for Inflammation Research, Queen's Medical Research Institute, University of EdinburghEdinburghUK
| | - Pranvera Sadiku
- University of Edinburgh Centre for Inflammation Research, Queen's Medical Research Institute, University of EdinburghEdinburghUK
| | - Sarah R. Walmsley
- University of Edinburgh Centre for Inflammation Research, Queen's Medical Research Institute, University of EdinburghEdinburghUK
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9
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Tarhriz V, Abkhooie L, Sarabi MM. Regulation of HIF-1 by MicroRNAs in Various Cardiovascular Diseases. Curr Cardiol Rev 2023; 19:51-56. [PMID: 37005512 PMCID: PMC10518879 DOI: 10.2174/1573403x19666230330105259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 01/04/2023] [Accepted: 02/07/2023] [Indexed: 04/04/2023] Open
Abstract
Today, we see an increase in death due to cardiovascular diseases all over the world, which has a lot to do with the regulation of oxygen homeostasis. Also, hypoxia-inducing factor 1 (HIF-1) is considered a vital factor in hypoxia and its physiological and pathological changes. HIF- 1 is involved in cellular activities, including proliferation, differentiation, and cell death in endothelial cells (ECs) and cardiomyocytes. Similar to HIF-1α, which acts as a protective element against various diseases in the cardiovascular system, the protective role of microRNAs (miRNAs) has also been proved using animal models. The number of miRNAs identified in the regulation of gene expression responsive to hypoxia and the importance of investigating the involvement of the non-coding genome in cardiovascular diseases is increasing, which shows the issue's importance. In this study, the molecular regulation of HIF-1 by miRNAs is considered to improve therapeutic approaches in clinical diagnoses of cardiovascular diseases.
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Affiliation(s)
- Vahideh Tarhriz
- Molecular Medicine Research Center, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
- Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Leila Abkhooie
- Razi Herbal Medicines Research Center, Lorestan University of Medical Sciences, Khorramabad, Iran
- Department of Medical Biotechnology, Faculty of Medicine, Lorestan University of Medical Sciences, Khorramabad, Iran
| | - Mostafa Moradi Sarabi
- Razi Herbal Medicines Research Center, Lorestan University of Medical Sciences, Khorramabad, Iran
- Department of Biochemistry and Genetics, School of Medicine, Lorestan University of Medical Sciences, Khorramabad, Iran
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10
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Shakir D, Batie M, Rocha S. Fixed Cell Immunofluorescence for Quantification of Hypoxia-Induced Changes in Histone Methylation. Methods Mol Biol 2023; 2675:261-269. [PMID: 37258769 DOI: 10.1007/978-1-0716-3247-5_19] [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] [Indexed: 06/02/2023]
Abstract
Hypoxia and its signalling pathway play a key role in human physiology and a variety of diseases. Alterations in histone methylation coordinate transcriptional responses to hypoxia. Here, we detail a fixed cell immunofluorescence method for quantifying hypoxia-induced changes in histone methylation, exemplified by the measurement of H3K27me3.
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Affiliation(s)
- Dilem Shakir
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Michael Batie
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Sonia Rocha
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK.
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11
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Aljoufi A, Zhang C, Ropa J, Chang W, Palam LR, Cooper S, Ramdas B, Capitano ML, Broxmeyer HE, Kapur R. Physioxia-induced downregulation of Tet2 in hematopoietic stem cells contributes to enhanced self-renewal. Blood 2022; 140:1263-1277. [PMID: 35772013 PMCID: PMC9479026 DOI: 10.1182/blood.2022015499] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 06/17/2022] [Indexed: 12/15/2022] Open
Abstract
Hematopoietic stem cells (HSCs) manifest impaired recovery and self-renewal with a concomitant increase in differentiation when exposed to ambient air as opposed to physioxia. Mechanism(s) behind this distinction are poorly understood but have the potential to improve stem cell transplantation. Single-cell RNA sequencing of HSCs in physioxia revealed upregulation of HSC self-renewal genes and downregulation of genes involved in inflammatory pathways and HSC differentiation. HSCs under physioxia also exhibited downregulation of the epigenetic modifier Tet2. Tet2 is α-ketoglutarate, iron- and oxygen-dependent dioxygenase that converts 5-methylcytosine to 5-hydroxymethylcytosine, thereby promoting active transcription. We evaluated whether loss of Tet2 affects the number and function of HSCs and hematopoietic progenitor cells (HPCs) under physioxia and ambient air. In contrast to wild-type HSCs (WT HSCs), a complete nonresponsiveness of Tet2-/- HSCs and HPCs to changes in oxygen tension was observed. Unlike WT HSCs, Tet2-/- HSCs and HPCs exhibited similar numbers and function in either physioxia or ambient air. The lack of response to changes in oxygen tension in Tet2-/- HSCs was associated with similar changes in self-renewal and quiescence genes among WT HSC-physioxia, Tet2-/- HSC-physioxia and Tet2-/- HSC-air. We define a novel molecular program involving Tet2 in regulating HSCs under physioxia.
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Affiliation(s)
| | - Chi Zhang
- Department of Medical and Molecular Genetics, and
| | - James Ropa
- Department of Microbiology and Immunology
| | - Wennan Chang
- Department of Medical and Molecular Genetics, and
| | - Lakshmi Reddy Palam
- Herman B Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | | | - Baskar Ramdas
- Herman B Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | | | | | - Reuben Kapur
- Department of Microbiology and Immunology
- Herman B Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
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12
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Kell DB, Pretorius E. The potential role of ischaemia-reperfusion injury in chronic, relapsing diseases such as rheumatoid arthritis, Long COVID, and ME/CFS: evidence, mechanisms, and therapeutic implications. Biochem J 2022; 479:1653-1708. [PMID: 36043493 PMCID: PMC9484810 DOI: 10.1042/bcj20220154] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 08/09/2022] [Accepted: 08/10/2022] [Indexed: 02/07/2023]
Abstract
Ischaemia-reperfusion (I-R) injury, initiated via bursts of reactive oxygen species produced during the reoxygenation phase following hypoxia, is well known in a variety of acute circumstances. We argue here that I-R injury also underpins elements of the pathology of a variety of chronic, inflammatory diseases, including rheumatoid arthritis, ME/CFS and, our chief focus and most proximally, Long COVID. Ischaemia may be initiated via fibrin amyloid microclot blockage of capillaries, for instance as exercise is started; reperfusion is a necessary corollary when it finishes. We rehearse the mechanistic evidence for these occurrences here, in terms of their manifestation as oxidative stress, hyperinflammation, mast cell activation, the production of marker metabolites and related activities. Such microclot-based phenomena can explain both the breathlessness/fatigue and the post-exertional malaise that may be observed in these conditions, as well as many other observables. The recognition of these processes implies, mechanistically, that therapeutic benefit is potentially to be had from antioxidants, from anti-inflammatories, from iron chelators, and via suitable, safe fibrinolytics, and/or anti-clotting agents. We review the considerable existing evidence that is consistent with this, and with the biochemical mechanisms involved.
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Affiliation(s)
- Douglas B. Kell
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, U.K
- The Novo Nordisk Foundation Centre for Biosustainability, Technical University of Denmark, Kemitorvet 200, 2800 Kgs Lyngby, Denmark
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, Private Bag X1 Matieland 7602, South Africa
| | - Etheresia Pretorius
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, U.K
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, Private Bag X1 Matieland 7602, South Africa
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13
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Kim J, Lee H, Yi SJ, Kim K. Gene regulation by histone-modifying enzymes under hypoxic conditions: a focus on histone methylation and acetylation. Exp Mol Med 2022; 54:878-889. [PMID: 35869366 PMCID: PMC9355978 DOI: 10.1038/s12276-022-00812-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 04/30/2022] [Accepted: 05/10/2022] [Indexed: 12/12/2022] Open
Abstract
Oxygen, which is necessary for sustaining energy metabolism, is consumed in many biochemical reactions in eukaryotes. When the oxygen supply is insufficient for maintaining multiple homeostatic states at the cellular level, cells are subjected to hypoxic stress. Hypoxia induces adaptive cellular responses mainly through hypoxia-inducible factors (HIFs), which are stabilized and modulate the transcription of various hypoxia-related genes. In addition, many epigenetic regulators, such as DNA methylation, histone modification, histone variants, and adenosine triphosphate-dependent chromatin remodeling factors, play key roles in gene expression. In particular, hypoxic stress influences the activity and gene expression of histone-modifying enzymes, which controls the posttranslational modification of HIFs and histones. This review covers how histone methylation and histone acetylation enzymes modify histone and nonhistone proteins under hypoxic conditions and surveys the impact of epigenetic modifications on gene expression. In addition, future directions in this area are discussed. New sequencing technologies are revealing how cells respond to hypoxia, insufficient oxygen, by managing gene activation. In multicellular organisms, gene activation is managed by how tightly a section of DNA is wound around proteins called histones; genes in tightly packed regions are inaccessible and inactive, whereas those in looser regions can be activated. Kyunghwan Kim, Sun-Ju Yi, and co-workers at Chungbuk National University in South Korea have reviewed recent data on how cells regulate gene activity under hypoxic conditions. Advances in sequencing technology have allowed genome-wide studies of how hypoxia affects DNA structure and gene activation, revealing that gene-specific modifications may be more important than genome-wide modifications. Hypoxia is implicated in several diseases, such as cancer and chronic metabolic diseases, and a better understanding of how it affects gene activation may help identify new treatments for hypoxia-related diseases.
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14
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Albracht SP. Hypothesis: mutual dependency of ascorbate and calcidiol for optimal performance of the immune system. Med Hypotheses 2022. [DOI: 10.1016/j.mehy.2022.110845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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15
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Batie M, Frost J, Shakir D, Rocha S. Regulation of chromatin accessibility by hypoxia and HIF. Biochem J 2022; 479:767-786. [PMID: 35258521 PMCID: PMC9022986 DOI: 10.1042/bcj20220008] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 03/07/2022] [Accepted: 03/08/2022] [Indexed: 11/17/2022]
Abstract
Reduced oxygen availability (hypoxia) can act as a signalling cue in physiological processes such as development, but also in pathological conditions such as cancer or ischaemic disease. As such, understanding how cells and organisms respond to hypoxia is of great importance. The family of transcription factors called Hypoxia Inducible Factors (HIFs) co-ordinate a transcriptional programme required for survival and adaptation to hypoxia. However, the effects of HIF on chromatin accessibility are currently unclear. Here, using genome wide mapping of chromatin accessibility via ATAC-seq, we find hypoxia induces loci specific changes in chromatin accessibility are enriched at a subset hypoxia transcriptionally responsive genes, agreeing with previous data using other models. We show for the first time that hypoxia inducible changes in chromatin accessibility across the genome are predominantly HIF dependent, rapidly reversible upon reoxygenation and partially mimicked by HIF-α stabilisation independent of molecular dioxygenase inhibition. This work demonstrates that HIF is central to chromatin accessibility alterations in hypoxia, and has implications for our understanding of gene expression regulation by hypoxia and HIF.
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Affiliation(s)
- Michael Batie
- Department of Molecular Physiology and Cell Signalling, Institute of Systems Molecular and Integrative Biology, University of Liverpool, Crown Street, Liverpool L697ZB, U.K
| | - Julianty Frost
- Department of Molecular Physiology and Cell Signalling, Institute of Systems Molecular and Integrative Biology, University of Liverpool, Crown Street, Liverpool L697ZB, U.K
| | - Dilem Shakir
- Department of Molecular Physiology and Cell Signalling, Institute of Systems Molecular and Integrative Biology, University of Liverpool, Crown Street, Liverpool L697ZB, U.K
| | - Sonia Rocha
- Department of Molecular Physiology and Cell Signalling, Institute of Systems Molecular and Integrative Biology, University of Liverpool, Crown Street, Liverpool L697ZB, U.K
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16
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Wojdyla Z, Borowski T. Properties of the Reactants and Their Interactions within and with the Enzyme Binding Cavity Determine Reaction Selectivities. The Case of Fe(II)/2-Oxoglutarate Dependent Enzymes. Chemistry 2022; 28:e202104106. [PMID: 34986268 DOI: 10.1002/chem.202104106] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Indexed: 12/12/2022]
Abstract
Fe(II)/2-oxoglutarate dependent dioxygenases (ODDs) share a double stranded beta helix (DSBH) fold and utilise a common reactive intermediate, ferryl species, to catalyse oxidative transformations of substrates. Despite the structural similarities, ODDs accept a variety of substrates and facilitate a wide range of reactions, that is hydroxylations, desaturations, (oxa)cyclisations and ring rearrangements. In this review we present and discuss the factors contributing to the observed (regio)selectivities of ODDs. They span from inherent properties of the reactants, that is, substrate molecule and iron cofactor, to the interactions between the substrate and the enzyme's binding cavity; the latter can counterbalance the effect of the former. Based on results of both experimental and computational studies dedicated to ODDs, we also line out the properties of the reactants which promote reaction outcomes other than the "default" hydroxylation. It turns out that the reaction selectivity depends on a delicate balance of interactions between the components of the investigated system.
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Affiliation(s)
- Zuzanna Wojdyla
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Kraków, Niezapominajek 8, 30239 Krakow, Poland
| | - Tomasz Borowski
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Kraków, Niezapominajek 8, 30239 Krakow, Poland
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17
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Dewhirst MW, Oleson JR, Kirkpatrick J, Secomb TW. Accurate Three-Dimensional Thermal Dosimetry and Assessment of Physiologic Response Are Essential for Optimizing Thermoradiotherapy. Cancers (Basel) 2022; 14:1701. [PMID: 35406473 PMCID: PMC8997141 DOI: 10.3390/cancers14071701] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 02/04/2023] Open
Abstract
Numerous randomized trials have revealed that hyperthermia (HT) + radiotherapy or chemotherapy improves local tumor control, progression free and overall survival vs. radiotherapy or chemotherapy alone. Despite these successes, however, some individuals fail combination therapy; not every patient will obtain maximal benefit from HT. There are many potential reasons for failure. In this paper, we focus on how HT influences tumor hypoxia, since hypoxia negatively influences radiotherapy and chemotherapy response as well as immune surveillance. Pre-clinically, it is well established that reoxygenation of tumors in response to HT is related to the time and temperature of exposure. In most pre-clinical studies, reoxygenation occurs only during or shortly after a HT treatment. If this were the case clinically, then it would be challenging to take advantage of HT induced reoxygenation. An important question, therefore, is whether HT induced reoxygenation occurs in the clinic that is of radiobiological significance. In this review, we will discuss the influence of thermal history on reoxygenation in both human and canine cancers treated with thermoradiotherapy. Results of several clinical series show that reoxygenation is observed and persists for 24-48 h after HT. Further, reoxygenation is associated with treatment outcome in thermoradiotherapy trials as assessed by: (1) a doubling of pathologic complete response (pCR) in human soft tissue sarcomas, (2) a 14 mmHg increase in pO2 of locally advanced breast cancers achieving a clinical response vs. a 9 mmHg decrease in pO2 of locally advanced breast cancers that did not respond and (3) a significant correlation between extent of reoxygenation (as assessed by pO2 probes and hypoxia marker drug immunohistochemistry) and duration of local tumor control in canine soft tissue sarcomas. The persistence of reoxygenation out to 24-48 h post HT is distinctly different from most reported rodent studies. In these clinical series, comparison of thermal data with physiologic response shows that within the same tumor, temperatures at the higher end of the temperature distribution likely kill cells, resulting in reduced oxygen consumption rate, while lower temperatures in the same tumor improve perfusion. However, reoxygenation does not occur in all subjects, leading to significant uncertainty about the thermal-physiologic relationship. This uncertainty stems from limited knowledge about the spatiotemporal characteristics of temperature and physiologic response. We conclude with recommendations for future research with emphasis on retrieving co-registered thermal and physiologic data before and after HT in order to begin to unravel complex thermophysiologic interactions that appear to occur with thermoradiotherapy.
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Affiliation(s)
- Mark W Dewhirst
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27710, USA
| | - James R Oleson
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27710, USA
| | - John Kirkpatrick
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Timothy W Secomb
- Department of Physiology, University of Arizona, Tucson, AZ 85724, USA
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18
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Wang K, Yang C, Li H, Liu X, Zheng M, Xuan Z, Mei Z, Wang H. Role of the Epigenetic Modifier JMJD6 in Tumor Development and Regulation of Immune Response. Front Immunol 2022; 13:859893. [PMID: 35359945 PMCID: PMC8963961 DOI: 10.3389/fimmu.2022.859893] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 02/22/2022] [Indexed: 11/13/2022] Open
Abstract
JMJD6 is a member of the Jumonji (JMJC) domain family of histone demethylases that contributes to catalyzing the demethylation of H3R2me2 and/or H4R3me2 and regulating the expression of specific genes. JMJD6-mediated demethylation modifications are involved in the regulation of transcription, chromatin structure, epigenetics, and genome integrity. The abnormal expression of JMJD6 is associated with the occurrence and development of a variety of tumors, including breast carcinoma, lung carcinoma, colon carcinoma, glioma, prostate carcinoma, melanoma, liver carcinoma, etc. Besides, JMJD6 regulates the innate immune response and affects many biological functions, as well as may play key roles in the regulation of immune response in tumors. Given the importance of epigenetic function in tumors, targeting JMJD6 gene by modulating the role of immune components in tumorigenesis and its development will contribute to the development of a promising strategy for cancer therapy. In this article, we introduce the structure and biological activities of JMJD6, followed by summarizing its roles in tumorigenesis and tumor development. Importantly, we highlight the potential functions of JMJD6 in the regulation of tumor immune response, as well as the development of JMJD6 targeted small-molecule inhibitors for cancer therapy.
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Affiliation(s)
- Kai Wang
- Research Center for Preclinical Medicine, Southwest Medical University, Luzhou, China
| | - Chao Yang
- National Engineering Research Center for Marine Aquaculture, Institute of Innovation and Application, Zhejiang Ocean University, Zhoushan, China
| | - Haibin Li
- Department of Pharmacy, 908th Hospital of Chinese PLA Joint Logistic Support Force, Yingtan, China
| | - Xiaoyan Liu
- Research Center for Preclinical Medicine, Southwest Medical University, Luzhou, China
| | - Meiling Zheng
- Research Center for Preclinical Medicine, Southwest Medical University, Luzhou, China
| | - Zixue Xuan
- Clinical Pharmacy Center, Department of Pharmacy, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, China
- *Correspondence: Zixue Xuan, ; Zhiqiang Mei, ; Haiyong Wang,
| | - Zhiqiang Mei
- Research Center for Preclinical Medicine, Southwest Medical University, Luzhou, China
- *Correspondence: Zixue Xuan, ; Zhiqiang Mei, ; Haiyong Wang,
| | - Haiyong Wang
- Department of Internal Medicine Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
- *Correspondence: Zixue Xuan, ; Zhiqiang Mei, ; Haiyong Wang,
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Wolf D, Muralidharan A, Mohan S. Role of prolyl hydroxylase domain proteins in bone metabolism. Osteoporos Sarcopenia 2022; 8:1-10. [PMID: 35415275 PMCID: PMC8987327 DOI: 10.1016/j.afos.2022.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 01/12/2022] [Accepted: 03/04/2022] [Indexed: 11/03/2022] Open
Abstract
Cellular metabolism requires dissolved oxygen gas. Because evolutionary refinements have constrained mammalian dissolved oxygen levels, intracellular oxygen sensors are vital for optimizing the bioenergetic and biosynthetic use of dissolved oxygen. Prolyl hydroxylase domain (PHD) homologs 1-3 (PHD1/2/3) are molecular oxygen dependent non-heme dioxygenases whose enzymatic activity is regulated by the concentration of dissolved oxygen. PHD oxygen dependency has evolved into an important intracellular oxygen sensor. The most well studied mechanism of PHD oxygen-sensing is its regulation of the hypoxia-inducible factor (HIF) hypoxia signaling pathway. Heterodimeric HIF transcription factor activity is regulated post-translationally by selective PHD proline hydroxylation of its HIF1α subunit, accelerating HIF1α ubiquitination and proteasomal degradation, preventing HIF heterodimer assembly, nuclear accumulation, and activation of its target oxygen homeostasis genes. Phd2 has been shown to be the key isoform responsible for HIF1α subunit regulation in many cell types and accordingly disruption of the Phd2 gene results in embryonic lethality. In bone cells Phd2 is expressed in high abundance and tightly regulated. Conditional disruption of the Phd1, Phd2 and/or Phd3 gene in various bone cell types using different Cre drivers reveals a major role for PHD2 in skeletal growth and development. In this review, we will summarize the state of current knowledge on the role and mechanism of action of PHD2 as oxygen sensor in regulating bone metabolism.
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Affiliation(s)
- David Wolf
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA, 92357, USA
| | - Aruljothi Muralidharan
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA, 92357, USA
| | - Subburaman Mohan
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA, 92357, USA
- Department of Medicine, Loma Linda University, Loma Linda, CA, 92354, USA
- Department Biochemistry and Orthopedic Surgery, Loma Linda University, Loma Linda, CA, 92354, USA
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20
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Batie M, Kenneth NS, Rocha S. Systems approaches to understand oxygen sensing: how multi-omics has driven advances in understanding oxygen-based signalling. Biochem J 2022; 479:245-257. [PMID: 35119457 PMCID: PMC8883490 DOI: 10.1042/bcj20210554] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/06/2022] [Accepted: 01/10/2022] [Indexed: 12/11/2022]
Abstract
Hypoxia is a common denominator in the pathophysiology of a variety of human disease states. Insight into how cells detect, and respond to low oxygen is crucial to understanding the role of hypoxia in disease. Central to the hypoxic response is rapid changes in the expression of genes essential to carry out a wide range of functions to adapt the cell/tissue to decreased oxygen availability. These changes in gene expression are co-ordinated by specialised transcription factors, changes to chromatin architecture and intricate balances between protein synthesis and destruction that together establish changes to the cellular proteome. In this article, we will discuss the advances of our understanding of the cellular oxygen sensing machinery achieved through the application of 'omics-based experimental approaches.
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Affiliation(s)
- Michael Batie
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Biosciences Building, Crown Street, Liverpool L697ZB, U.K
| | - Niall S. Kenneth
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Biosciences Building, Crown Street, Liverpool L697ZB, U.K
| | - Sonia Rocha
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Biosciences Building, Crown Street, Liverpool L697ZB, U.K
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21
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PBRM1 Cooperates with YTHDF2 to Control HIF-1α Protein Translation. Cells 2021; 10:cells10061425. [PMID: 34200988 PMCID: PMC8228889 DOI: 10.3390/cells10061425] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/27/2021] [Accepted: 06/04/2021] [Indexed: 11/16/2022] Open
Abstract
PBRM1, a component of the chromatin remodeller SWI/SNF, is often deleted or mutated in human cancers, most prominently in renal cancers. Core components of the SWI/SNF complex have been shown to be important for the cellular response to hypoxia. Here, we investigated how PBRM1 controls HIF-1α activity. We found that PBRM1 is required for HIF-1α transcriptional activity and protein levels. Mechanistically, PBRM1 is important for HIF-1α mRNA translation, as absence of PBRM1 results in reduced actively translating HIF-1α mRNA. Interestingly, we found that PBRM1, but not BRG1, interacts with the m6A reader protein YTHDF2. HIF-1α mRNA is m6A-modified, bound by PBRM1 and YTHDF2. PBRM1 is necessary for YTHDF2 binding to HIF-1α mRNA and reduction of YTHDF2 results in reduced HIF-1α protein expression in cells. Our results identify a SWI/SNF-independent function for PBRM1, interacting with HIF-1α mRNA and the epitranscriptome machinery. Furthermore, our results suggest that the epitranscriptome-associated proteins play a role in the control of hypoxia signalling pathways.
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22
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Hypoxia-Induced Cancer Cell Responses Driving Radioresistance of Hypoxic Tumors: Approaches to Targeting and Radiosensitizing. Cancers (Basel) 2021; 13:cancers13051102. [PMID: 33806538 PMCID: PMC7961562 DOI: 10.3390/cancers13051102] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/21/2021] [Accepted: 02/25/2021] [Indexed: 12/14/2022] Open
Abstract
Simple Summary Some regions of aggressive malignancies experience hypoxia due to inadequate blood supply. Cancer cells adapting to hypoxic conditions somehow become more resistant to radiation exposure and this decreases the efficacy of radiotherapy toward hypoxic tumors. The present review article helps clarify two intriguing points: why hypoxia-adapted cancer cells turn out radioresistant and how they can be rendered more radiosensitive. The critical molecular targets associated with intratumoral hypoxia and various approaches are here discussed which may be used for sensitizing hypoxic tumors to radiotherapy. Abstract Within aggressive malignancies, there usually are the “hypoxic zones”—poorly vascularized regions where tumor cells undergo oxygen deficiency through inadequate blood supply. Besides, hypoxia may arise in tumors as a result of antiangiogenic therapy or transarterial embolization. Adapting to hypoxia, tumor cells acquire a hypoxia-resistant phenotype with the characteristic alterations in signaling, gene expression and metabolism. Both the lack of oxygen by itself and the hypoxia-responsive phenotypic modulations render tumor cells more radioresistant, so that hypoxic tumors are a serious challenge for radiotherapy. An understanding of causes of the radioresistance of hypoxic tumors would help to develop novel ways for overcoming this challenge. Molecular targets for and various approaches to radiosensitizing hypoxic tumors are considered in the present review. It is here analyzed how the hypoxia-induced cellular responses involving hypoxia-inducible factor-1, heat shock transcription factor 1, heat shock proteins, glucose-regulated proteins, epigenetic regulators, autophagy, energy metabolism reprogramming, epithelial–mesenchymal transition and exosome generation contribute to the radioresistance of hypoxic tumors or may be inhibited for attenuating this radioresistance. The pretreatments with a multitarget inhibition of the cancer cell adaptation to hypoxia seem to be a promising approach to sensitizing hypoxic carcinomas, gliomas, lymphomas, sarcomas to radiotherapy and, also, liver tumors to radioembolization.
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23
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Xiao M, Li Z, Zhu L, Wang J, Zhang B, Zheng F, Zhao B, Zhang H, Wang Y, Zhang Z. The Multiple Roles of Ascorbate in the Abiotic Stress Response of Plants: Antioxidant, Cofactor, and Regulator. FRONTIERS IN PLANT SCIENCE 2021; 12:598173. [PMID: 33912200 PMCID: PMC8072462 DOI: 10.3389/fpls.2021.598173] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 03/17/2021] [Indexed: 05/13/2023]
Abstract
Ascorbate (ASC) plays a critical role in plant stress response. The antioxidant role of ASC has been well-studied, but there are still several confusing questions about the function of ASC in plant abiotic stress response. ASC can scavenge reactive oxygen species (ROS) and should be helpful for plant stress tolerance. But in some cases, increasing ASC content impairs plant abiotic stress tolerance, whereas, inhibiting ASC synthesis or regeneration enhances plant stress tolerance. This confusing phenomenon indicates that ASC may have multiple roles in plant abiotic stress response not just as an antioxidant, though many studies more or less ignored other roles of ASC in plant. In fact, ACS also can act as the cofactor of some enzymes, which are involved in the synthesis, metabolism, and modification of a variety of substances, which has important effects on plant stress response. In addition, ASC can monitor and effectively regulate cell redox status. Therefore, we believe that ASC has atleast triple roles in plant abiotic stress response: as the antioxidant to scavenge accumulated ROS, as the cofactor to involve in plant metabolism, or as the regulator to coordinate the actions of various signal pathways under abiotic stress. The role of ASC in plant abiotic stress response is important and complex. The detail role of ASC in plant abiotic stress response should be analyzed according to specific physiological process in specific organ. In this review, we discuss the versatile roles of ASC in the response of plants to abiotic stresses.
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Affiliation(s)
- Minggang Xiao
- Biotechnology Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Zixuan Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, China
| | - Li Zhu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, China
| | - Jiayi Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, China
| | - Bo Zhang
- Biotechnology Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Fuyu Zheng
- Biotechnology Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Beiping Zhao
- Biotechnology Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Haiwen Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, China
| | - Yujie Wang
- Biotechnology Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin, China
- Yujie Wang,
| | - Zhijin Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- National Key Facility of Crop Gene Resources and Genetic Improvement, Beijing, China
- *Correspondence: Zhijin Zhang,
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