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Baxter MA, Denholm M, Kingdon SJ, Kathirgamakarthigeyan S, Parikh S, Shakir R, Johnson R, Martin H, Walton M, Yao W, Swan A, Samuelson C, Ren X, Cooper A, Gray HL, Clifton S, Ball J, Gullick G, Anderson M, Dodd L, Hayhurst H, Salama M, Shotton R, Britton F, Christodoulou T, Abdul-Hamid A, Eichholz A, Evans RM, Wallroth P, Gibson F, Poole K, Rowe M, Harris J. CAnceR IN PreGnancy (CARING) - a retrospective study of cancer diagnosed during pregnancy in the United Kingdom. Br J Cancer 2024; 130:1261-1268. [PMID: 38383704 PMCID: PMC11014900 DOI: 10.1038/s41416-024-02605-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/25/2024] [Accepted: 01/29/2024] [Indexed: 02/23/2024] Open
Abstract
BACKGROUND The incidence of cancer diagnosed during pregnancy is increasing. Data relating to investigation and management, as well as maternal and foetal outcomes is lacking in a United Kingdom (UK) population. METHODS In this retrospective study we report data from 119 patients diagnosed with cancer during pregnancy from 14 cancer centres in the UK across a five-year period (2016-2020). RESULTS Median age at diagnosis was 33 years, with breast, skin and haematological the most common primary sites. The majority of cases were new diagnoses (109 patients, 91.6%). Most patients were treated with radical intent (96 patients, 80.7%), however, gastrointestinal cancers were associated with a high rate of palliative intent treatment (63.6%). Intervention was commenced during pregnancy in 68 (57.1%) patients; 44 (37%) had surgery and 31 (26.1%) received chemotherapy. Live births occurred in 98 (81.7%) of the cases, with 54 (55.1%) of these delivered by caesarean section. Maternal mortality during the study period was 20.2%. CONCLUSIONS This is the first pan-tumour report of diagnosis, management and outcomes of cancer diagnosed during pregnancy in the UK. Our findings demonstrate proof of concept that data collection is feasible and highlight the need for further research in this cohort of patients.
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Affiliation(s)
- M A Baxter
- Division of Molecular and Clinical Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK.
- Tayside Cancer Centre, Ninewells Hospital and Medical School, NHS Tayside, Dundee, UK.
| | - M Denholm
- Department of Oncology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
- Early Cancer Institute, Department of Oncology, University of Cambridge, Cambridge, UK
| | - S J Kingdon
- Exeter Oncology Centre, Royal Devon University Hospitals NHS Trust, Exeter, UK
| | | | - S Parikh
- Department of Oncology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - R Shakir
- Oncology Department, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - R Johnson
- Oncology Department, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - H Martin
- Department of Oncology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
- Early Cancer Institute, Department of Oncology, University of Cambridge, Cambridge, UK
- Cancer Research UK Cambridge Institute, Cambridge University, Cambridge, UK
| | - M Walton
- Department of Oncology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - W Yao
- Department of Oncology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - A Swan
- Edinburgh Cancer Centre, Western General Hospital, NHS Lothian, Edinburgh, UK
| | - C Samuelson
- Edinburgh Cancer Centre, Western General Hospital, NHS Lothian, Edinburgh, UK
| | - X Ren
- Edinburgh Cancer Centre, Western General Hospital, NHS Lothian, Edinburgh, UK
| | - A Cooper
- Edinburgh Cancer Centre, Western General Hospital, NHS Lothian, Edinburgh, UK
| | - H-L Gray
- Tayside Cancer Centre, Ninewells Hospital and Medical School, NHS Tayside, Dundee, UK
| | - S Clifton
- Bristol Haematology and Oncology Centre, Bristol, UK
| | - J Ball
- Bristol Haematology and Oncology Centre, Bristol, UK
| | - G Gullick
- Oncology Department, Royal United Hospitals NHS Foundation Trust, Bath, UK
| | - M Anderson
- Northern Centre for Cancer Care, The Newcastle Upon Tyne Hospitals NHS Foundation Trust, The Newcastle Upon Tyne, UK
| | - L Dodd
- Northern Centre for Cancer Care, The Newcastle Upon Tyne Hospitals NHS Foundation Trust, The Newcastle Upon Tyne, UK
| | - H Hayhurst
- Northern Centre for Cancer Care, The Newcastle Upon Tyne Hospitals NHS Foundation Trust, The Newcastle Upon Tyne, UK
| | - M Salama
- Department of Oncology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - R Shotton
- Department of Medical Oncology, The Christie NHS Foundation Trust, Manchester, UK
| | - F Britton
- Department of Medical Oncology, The Christie NHS Foundation Trust, Manchester, UK
| | - T Christodoulou
- Department of Medical Oncology, The Christie NHS Foundation Trust, Manchester, UK
| | - A Abdul-Hamid
- Department of Oncology, Royal Surrey County Hospital NHS Trust, Surrey, UK
| | - A Eichholz
- Department of Oncology, Buckinghamshire Healthcare NHS Trust, Buckinghamshire, UK
| | - R M Evans
- South West Wales Cancer Centre, Swansea Bay NHS Trust, Swansea, UK
| | | | - F Gibson
- School of Health Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
- Centre for Outcomes and Experience Research in Children's Health, Illness and Disability, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - K Poole
- The Institute of Cancer Research, Clinical Trials and Statistics Unit, Belmont, Sutton, Surrey, UK
| | - M Rowe
- Sunrise Oncology Centre, Royal Cornwall Hospitals NHS Trust, Truro, UK
| | - J Harris
- School of Health Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
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Ash PA, Carr SB, Reeve HA, Skorupskaitė A, Rowbotham JS, Shutt R, Frogley MD, Evans RM, Cinque G, Armstrong FA, Vincent KA. Generating single metalloprotein crystals in well-defined redox states: electrochemical control combined with infrared imaging of a NiFe hydrogenase crystal. Chem Commun (Camb) 2018; 53:5858-5861. [PMID: 28504793 PMCID: PMC5708527 DOI: 10.1039/c7cc02591b] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We describe an approach to generating and verifying well-defined redox states in metalloprotein single crystals by combining electrochemical control with synchrotron infrared microspectroscopic imaging. For NiFe hydrogenase 1 from Escherichia coli we demonstrate fully reversible and uniform electrochemical reduction from the oxidised inactive to the fully reduced state, and temporally resolve steps during this reduction.
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Affiliation(s)
- P A Ash
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK.
| | - S B Carr
- Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0FA, UK and Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - H A Reeve
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK.
| | - A Skorupskaitė
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK.
| | - J S Rowbotham
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK.
| | - R Shutt
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK.
| | - M D Frogley
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX, UK
| | - R M Evans
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK.
| | - G Cinque
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX, UK
| | - F A Armstrong
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK.
| | - K A Vincent
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK.
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Affiliation(s)
- D G Dunlop
- Department of Burns & Plastic Surgery, Morriston Hospital, Swansea, Wales
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Hennessey DB, Kinnear NJ, Evans RM, Hagan C, Thwaini A. Is confirmation of ureteric stent placement in laparoscopic pyeloplasty necessary? Int Urol Nephrol 2017; 49:931-936. [PMID: 28260225 DOI: 10.1007/s11255-017-1560-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 02/24/2017] [Indexed: 10/20/2022]
Abstract
PURPOSE Placement of an antegrade double-J (JJ) ureteric stent is an important component of pyeloplasty. Correct siting of distal end of the stent in the bladder is essential for ease of removal. To date, no studies have compared methods for confirming stent position. This study aims to address that void in the literature. METHODS Eligible patients underwent laparoscopic pyeloplasty with antegrade stent placement at our institution from 2007 to 2015 inclusive. Methods to verify distal stent position of rigid cystoscopy, artificial bladder filling or no confirmation were compared. Effectiveness was determined by the proportion of malpositioned stents detected intra-operatively compared to the total found malpositioned, both intra-operatively and during follow-up. RESULTS A total of 75 patients underwent laparoscopic pyeloplasty. Forty-six (61.3%) patients had distal stent position assessed intra-operatively, comprising 27 by cystoscopy and 19 by artificial bladder filling, while for 29 (38.7%) patients no verification method was used. Cystoscopy, artificial bladder filling and no confirmation detected intra-operatively 2, 1 and 0 malpositioned stents, from malpositioned stent totals of 2, 2 and 1, respectively. CONCLUSION Malposition of JJ ureteric stent is uncommon, and omitting intra-operative position verification appears reasonable in select cases. Artificial bladder filling can help detect malpositioned JJ stents without repositioning the patient for cystoscopy. However, our results suggest both may be unreliable. If stent malposition is suspected, certainty is desired or extended operative duration is less critical, then the surgeon should proceed with cystoscopy.
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Affiliation(s)
- D B Hennessey
- Department of Urology, Belfast City Hospital, Lisburn Road, Belfast, UK.,Department of Urology, Austin Hospital, 145 Studley Road, Heidelberg, VIC, 3084, Australia
| | - N J Kinnear
- Department of Urology, Austin Hospital, 145 Studley Road, Heidelberg, VIC, 3084, Australia.
| | - R M Evans
- Department of Urology, Belfast City Hospital, Lisburn Road, Belfast, UK
| | - C Hagan
- Department of Urology, Belfast City Hospital, Lisburn Road, Belfast, UK
| | - A Thwaini
- Department of Urology, Belfast City Hospital, Lisburn Road, Belfast, UK
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Burkill GJC, Evans RM, Raman VV, Connor SEJ. Modern Radiology in the Management of Head and Neck Cancer. Clin Oncol (R Coll Radiol) 2016; 28:440-50. [PMID: 27156741 DOI: 10.1016/j.clon.2016.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 03/15/2016] [Accepted: 03/17/2016] [Indexed: 12/17/2022]
Abstract
The accurate staging of head and neck cancer is vital to direct appropriate management strategies and to deliver the best radiation therapy and surgery. Initial challenges in head and neck cancer imaging include determination of T- and N-stage, stage migration with detection of metastatic disease and identification of primary disease in the patient presenting with nodal metastases. In follow-up, imaging has an important role in assessing patients who may require salvage surgery after radiotherapy and assessing clinical change that may represent either residual/recurrent disease or radiation effects. This overview gathers recent evidence on the optimal use of currently readily available imaging modalities (ultrasound, computed tomography, magnetic resonance imaging and positron emission tomography-computed tomography) in the context of head and neck squamous cell cancers.
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Affiliation(s)
- G J C Burkill
- Brighton and Sussex University Hospitals NHS Trust, Brighton, UK.
| | - R M Evans
- Abertawe Bro Morgannwg LHB, College of Medicine, Swansea University, Swansea, UK
| | - V V Raman
- Brighton and Sussex University Hospitals NHS Trust, Brighton, UK
| | - S E J Connor
- Guy's and St. Thomas' NHS Foundation Trust, London, UK
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Mounsey RB, Martin HL, Nelson MC, Evans RM, Teismann P. The effect of neuronal conditional knock-out of peroxisome proliferator-activated receptors in the MPTP mouse model of Parkinson's disease. Neuroscience 2015; 300:576-84. [PMID: 26028469 PMCID: PMC4512257 DOI: 10.1016/j.neuroscience.2015.05.048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 05/19/2015] [Accepted: 05/20/2015] [Indexed: 01/01/2023]
Abstract
Activation of peroxisome proliferator-activated receptors (PPARs), namely PPARγ and PPARδ, has been shown to provide neuroprotection in a number of neurodegenerative disorders, such as Alzheimer's and Parkinson's disease (PD). The observed neuroprotective effects in experimental models of PD have been linked to anti-oxidant and anti-inflammatory actions. This study aimed to analyze the full influence of these receptors in neuroprotection by generating a nerve cell-specific conditional knock-out of these receptors and subjecting these genetically modified mice to the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) neurotoxin to model dopaminergic degeneration. Mice null for both receptors show the lowest levels of tyrosine hydroxylase (TH)-positive cell bodies following MPTP administration. Presence of one or both these receptors show a trend toward protection against this degeneration, as higher dopaminergic cell immunoreactivity and striatal monoamine levels are evident. These data supplement recent studies that have elected to use agonists of the receptors to regulate immune responses. The results place further importance on the activation of PPARs and the neuroprotective roles these have in inflammatory processes linked to neurodegenerative processes.
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Affiliation(s)
- R B Mounsey
- School of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - H L Martin
- School of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom; Institute of Molecular Medicine, University of Leeds, Leeds, United Kingdom
| | - M C Nelson
- Gene Expression Laboratory, Salk Institute, La Jolla, CA, USA
| | - R M Evans
- Gene Expression Laboratory, Salk Institute, La Jolla, CA, USA
| | - P Teismann
- School of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom.
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Abstract
The Swansea Morriston Achilles Rupture Treatment (SMART) programme was introduced in 2008. This paper summarises the outcome of this programme. Patients with a rupture of the Achilles tendon treated in our unit follow a comprehensive management protocol that includes a dedicated Achilles clinic, ultrasound examination, the use of functional orthoses, early weight-bearing, an accelerated exercise regime and guidelines for return to work and sport. The choice of conservative or surgical treatment was based on ultrasound findings. The rate of re-rupture, the outcome using the Achilles Tendon Total Rupture Score (ATRS) and the Achilles Tendon Repair Score, (AS), and the complications were recorded. An elementary cost analysis was also performed. Between 2008 and 2014 a total of 273 patients presented with an acute rupture 211 of whom were managed conservatively and 62 had surgical repair. There were three re-ruptures (1.1%). There were 215 men and 58 women with a mean age of 46.5 years (20 to 86). Functional outcome was satisfactory. Mean ATRS and AS at four months was 53.0 (sd 14), 64.9 (sd 15) (n = 135), six months 67.8 (sd 16), 73.8 (sd 15) (n = 103) and nine months (72.4; sd 14) 72.3 (sd 13) (n = 43). The programme realised estimated cost savings exceeding £91 000 per annum. The SMART programme resulted in a low rate of re-rupture, a satisfactory outcome, a reduced rate of surgical intervention and a reduction in healthcare costs. Cite this article: Bone Joint J 2015; 97-B:510–15.
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Affiliation(s)
- A. M. Hutchison
- Morriston Hospital, ABMU
Health Board, Orthopaedic Department, Swansea, SA6 6NL, UK
| | - C. Topliss
- Morriston Hospital, ABMU
Health Board, Orthopaedic Department, Swansea, SA6 6NL, UK
| | - D. Beard
- University of Oxford & Morriston Hospital, Institute of Musculoskeletal Sciences, Swansea, UK
| | - R. M. Evans
- Morriston Hospital / Swansea University
College of Medicine, Radiology Dept, Morriston
Swansea, SA6 6NL, UK
| | - P. Williams
- Morriston Hospital, ABMU
Health Board, Orthopaedic Department, Swansea, SA6 6NL, UK
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8
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Abstract
We conducted a randomised controlled trial to determine whether active intense pulsed light (IPL) is an effective treatment for patients with chronic mid-body Achilles tendinopathy. A total of 47 patients were randomly assigned to three weekly therapeutic or placebo IPL treatments. The primary outcome measure was the Victorian Institute of Sport Assessment – Achilles (VISA-A) score. Secondary outcomes were a visual analogue scale for pain (VAS) and the Lower Extremity Functional Scale (LEFS). Outcomes were recorded at baseline, six weeks and 12 weeks following treatment. Ultrasound assessment of the thickness of the tendon and neovascularisation were also recorded before and after treatment. There was no significant difference between the groups for any of the outcome scores or ultrasound measurements by 12 weeks, showing no measurable benefit from treatment with IPL in patients with Achilles tendinopathy. Cite this article: Bone Joint J 2013;95-B:504–9.
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Affiliation(s)
- A. M. Hutchison
- Abertawe Bro Morgannwg University Health
Board and College of Medicine, Swansea University, Physiotherapy
Department, Morriston Hospital, Swansea
SA6 6NL, UK
| | - I. Pallister
- Abertawe Bro Morgannwg University Health
Board and College of Medicine, Swansea University, Physiotherapy
Department, Morriston Hospital, Swansea
SA6 6NL, UK
| | - R. M. Evans
- Abertawe Bro Morgannwg University Health
Board, Radiology Department, Morriston
Hospital, Swansea SA6 6NL, UK
| | - O. Bodger
- Swansea University, College
of Medicine, Singleton Park, Swansea
SA2 8PP, UK
| | - C. J. Topliss
- Abertawe Bro Morgannwg University Health
Board, Orthopaedic Department, Morriston
Hospital, Swansea SA6 6NL, UK
| | - P. Williams
- Abertawe Bro Morgannwg University Health
Board, Orthopaedic Department, Morriston
Hospital, Swansea SA6 6NL, UK
| | - D. J. Beard
- Nuffield Department of Orthopaedics, Rheumatology & Musculoskeletal Sciences, Institute of Musculoskeletal Sciences, University of Oxford, Botnar Centre, Nuffield Orthopaedic Centre, Headington, Oxford OX3 7LD, UK
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Uhlenhaut NH, Barish GD, Yu RT, Downes M, Hübner N, Evans RM. The GR at inflammatory crossroads. Exp Clin Endocrinol Diabetes 2012. [DOI: 10.1055/s-0032-1330829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Warren JM, Iversen CM, Garten CT, Norby RJ, Childs J, Brice D, Evans RM, Gu L, Thornton P, Weston DJ. Timing and magnitude of C partitioning through a young loblolly pine (Pinus taeda L.) stand using 13C labeling and shade treatments. Tree Physiol 2012; 32:799-813. [PMID: 22210530 DOI: 10.1093/treephys/tpr129] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The dynamics of rapid changes in carbon (C) partitioning within forest ecosystems are not well understood, which limits improvement of mechanistic models of C cycling. Our objective was to inform model processes by describing relationships between C partitioning and accessible environmental or physiological measurements, with a special emphasis on short-term C flux through a forest ecosystem. We exposed eight 7-year-old loblolly pine (Pinus taeda L.) trees to air enriched with (13)CO(2) and then implemented adjacent light shade (LS) and heavy shade (HS) treatments in order to manipulate C uptake and flux. The impacts of shading on photosynthesis, plant water potential, sap flow, basal area growth, root growth and soil CO(2) efflux rate (CER) were assessed for each tree over a 3-week period. The progression of the (13)C label was concurrently tracked from the atmosphere through foliage, phloem, roots and surface soil CO(2) efflux. The HS treatment significantly reduced C uptake, sap flow, stem growth and fine root standing crop, and resulted in greater residual soil water content to 1 m depth. Soil CER was strongly correlated with sap flow on the previous day, but not the current day, with no apparent treatment effect on the relationship. Although there were apparent reductions in new C flux belowground, the HS treatment did not noticeably reduce the magnitude of belowground autotrophic and heterotrophic respiration based on surface soil CER, which was overwhelmingly driven by soil temperature and moisture. The (13)C label was immediately detected in foliage on label day (half-life = 0.5 day), progressed through phloem by Day 2 (half-life = 4.7 days), roots by Days 2-4, and subsequently was evident as respiratory release from soil which peaked between Days 3 and 6. The δ(13)C of soil CO(2) efflux was strongly correlated with phloem δ(13)C on the previous day, or 2 days earlier. While the (13)C label was readily tracked through the ecosystem, the fate of root C through respiratory, mycorrhizal or exudative release pathways was not assessed. These data detail the timing and relative magnitude of C flux through various components of a young pine stand in relation to environmental conditions.
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Affiliation(s)
- J M Warren
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
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Abstract
Obesity, and in particular central adiposity, is a key feature of metabolic syndrome, which includes trends toward increased triglycerides, insulin resistance, high blood pressure, hypercholesterolemia, and heart disease. It has a prevalence of 25% or more and is a dominant component of the health care budgets in Western societies. In addition to genetic causes, high-fat diets and disrupted sleep patterns have major influences on the development of metabolic syndrome. Recent studies have demonstrated active roles for the nuclear receptor superfamily and the energy-sensing kinase adenosine monophosphate (AMP)-activated protein kinase (AMPK) in regulating metabolism and circadian rhythm. In this chapter, we review these findings and attempt to develop a better understanding of the interplay between metabolism and circadian rhythm and their coordinated regulation by nuclear receptors and AMPK. This supraregulatory network may be considered a target for novel therapeutic applications against metabolic syndrome.
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Affiliation(s)
- W Fan
- Gene Expression Laboratory, Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
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Evans RM, Davies M. ScoreCentre: a computer program to assist with collection and calculation of BBB locomotor scale data. J Neurosci Methods 2010; 194:102-7. [PMID: 20933007 DOI: 10.1016/j.jneumeth.2010.09.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Revised: 09/15/2010] [Accepted: 09/26/2010] [Indexed: 10/19/2022]
Abstract
The Basso, Beattie and Bresnahan (BBB) Locomotor Rating Scale is a standardized assessment scale for use in experimental spinal cord injury (SCI) research. This paper describes a computer program, ScoreCentre, which aims to simplify the recording and handling of BBB locomotor scale data. The program assists with the recording of observational data from open-field testing and then automatically calculates BBB scores. Possible errors associated with data entry and manual calculation of scores are thus essentially eliminated. In addition, significant time is saved by the automated derivation of scores and subscores and elimination of the need to manually transfer data from paper records to a computer. ScoreCentre can also be used as a training aid, to help familiarize users with the BBB scale and to explore how changes in the observations impact on overall BBB score. ScoreCentre includes simple experiment management functions such as control of trial blinding, administration of drugs in a blinded fashion and longitudinal data analysis. ScoreCentre provides all the advantages of electronic records, such as ease of use, analysis and archiving, and allows the elimination of paper records if appropriate. When paper records are required, for example for archiving and auditing, they can be automatically produced by ScoreCentre. ScoreCentre will assist with both the learning and use of the BBB locomotor scale, thus facilitating the use of this standardized outcome measure in SCI research. ScoreCentre is available to download from www.rmeonline.net/scorecentre.
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Affiliation(s)
- R M Evans
- Department of Pharmacology, Centre for Toxicology, School of Pharmacy, University of London, London, UK.
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Sternsdorf T, Ocampo-Bayuga C, Haschke A, Dierk K, Prall S, Horstmann M, Evans RM. Positive evidence for a role of the PML pathway in leukemogenesis of acute promyelocytic leukemia. Klin Padiatr 2010. [DOI: 10.1055/s-0030-1254462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Tillin T, Evans RM, Witt NW, Sharp PS, McKeigue PM, Chaturvedi N, Hughes AD. Ethnic differences in retinal microvascular structure. Diabetologia 2008; 51:1719-22. [PMID: 18626625 DOI: 10.1007/s00125-008-1096-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2008] [Accepted: 06/12/2008] [Indexed: 11/30/2022]
Abstract
AIMS/HYPOTHESIS People of African origin have increased risk of stroke and retinal microvascular disease compared with populations of European origin. We compared quantitative measures of retinal microvasculature in British white Europeans and African Caribbeans. METHODS Population-based study of 215 (45% male) British African-Caribbean migrants and 323 (48% male) white Europeans aged 40-69 years. Digitised retinal images were analysed using a validated semi-automated system. RESULTS Arteriolar optimality deviation, an indicator of endothelial dysfunction, was greater in African Caribbeans (age- and sex-adjusted means [95% CIs]: 0.06 [0.05-0.06] vs 0.04 [0.04-0.05], p = 0.004); this was unexplained by conventional risk factors. Arteriolar diameters were narrower in African Caribbeans (age- and sex-adjusted means [95% CIs]: 18.4 [18.1-18.6] vs 17.9 [17.6-18.2], p = 0.011). These ethnic differences in diameters were attenuated on adjustment for systolic BP (SBP) (adjusted means: 18.2 vs 18.1, p = 0.31). However, there was a significant interaction (p = 0.011) between diabetes and SBP, such that SBP was strongly associated with arteriolar diameter in people without diabetes, but not in those with diabetes (adjusted beta-coefficients for SBP: Europeans: -0.42, p = 0.002 vs 0.17, p = 0.69, African Caribbeans: -0.35, p = 0.023 vs 0.01, p = 0.96). Other measures of retinal vasculature did not differ by ethnicity. CONCLUSIONS/INTERPRETATION British African Caribbeans appear to have poorer retinal arteriolar endothelial function than white Europeans. Higher BPs explained the narrower arterioles in African Caribbeans; however, patterns of association between arteriolar narrowing and BP suggest the possibility that cerebral autoregulation and/or remodelling might be adversely affected by diabetes in both ethnic groups.
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Affiliation(s)
- T Tillin
- International Centre for Circulatory Health, Imperial College London, 59 North Wharf Road, London W2 1LA, UK.
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Evans RM, Scott RH, Ross RA. Chronic exposure of sensory neurones to increased levels of nerve growth factor modulates CB1/TRPV1 receptor crosstalk. Br J Pharmacol 2007; 152:404-13. [PMID: 17700720 PMCID: PMC2042953 DOI: 10.1038/sj.bjp.0707411] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Anandamide (AEA) activates both cannabinoid CB(1) and TRPV1 receptors, which are expressed on cultured dorsal root ganglion neurones. Increased levels of nerve growth factor (NGF) are associated with chronic pain states. EXPERIMENTAL APPROACH The aim of this study was to compare of the effects of AEA on CB(1) receptor signalling and TRPV1-CB(1) crosstalk in low and high concentrations of NGF, using voltage-clamp electrophysiology and Fura-2 calcium imaging. KEY RESULTS Chronic exposure to high NGF (200 ng ml(-1)) as compared to low NGF (20 ng ml(-1)) increases the proportion of neurones that exhibit an inward current in response to AEA (1 microM), from 7 to 29%. In contrast, inhibition of voltage-gated calcium currents by AEA is not significantly different in low NGF (33+/-9%, compared to high NGF 28+/-6%). Crosstalk between CB and TRPV1 receptors is modulated by exposure to high NGF. In low NGF, exposure to the CB(1) receptor antagonist, SR141716A, (100 nM) increases the percentage of neurones in which AEA elicits an increase in [Ca(2+)](i), from 10 to 23%. In high NGF, the antagonist does not alter the percentage of responders (33 to 30%). In low NGF, exposure to the CB receptor agonist, WIN55 (1 microM) reduces capsaicin-mediated increases in [Ca(2+)](i) to 28+/-8% of control as compared to an enhancement to 172+/-26% of control observed in high NGF. CONCLUSIONS AND IMPLICATIONS We conclude that cannabinoid-mediated modulation of TRPV1 receptor activation is altered after exposure to high NGF.
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MESH Headings
- Animals
- Animals, Newborn
- Arachidonic Acids/pharmacology
- Calcium/metabolism
- Calcium Channels/drug effects
- Calcium Channels/metabolism
- Cannabinoid Receptor Modulators/pharmacology
- Cells, Cultured
- Chronic Disease
- Dose-Response Relationship, Drug
- Electrophysiology
- Endocannabinoids
- Fura-2
- Ganglia, Spinal/cytology
- Ganglia, Spinal/drug effects
- Ganglia, Spinal/metabolism
- Nerve Growth Factor/administration & dosage
- Nerve Growth Factor/pharmacology
- Pain/drug therapy
- Pain/physiopathology
- Patch-Clamp Techniques
- Polyunsaturated Alkamides/pharmacology
- Rats
- Receptor, Cannabinoid, CB1/drug effects
- Receptor, Cannabinoid, CB1/metabolism
- Signal Transduction/drug effects
- TRPV Cation Channels/drug effects
- TRPV Cation Channels/metabolism
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Affiliation(s)
- R M Evans
- Medical Faculty, University of Calgary Calgary, Canada
| | - R H Scott
- Institute of Medical Sciences, University of Aberdeen Aberdeen, Scotland, UK
| | - R A Ross
- Institute of Medical Sciences, University of Aberdeen Aberdeen, Scotland, UK
- Author for correspondence:
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16
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Abstract
As ligand-dependent transcription factors, the nuclear receptor superfamily governs a remarkable array of rhythmic physiologic processes such as metabolism and reproduction. To provide a "molecular blueprint" for nuclear receptor function in circadian biology, we established a diurnal expression profile of all mouse nuclear receptors in critical metabolic tissues. Our finding of broad expression and tissue-specific oscillation of nuclear receptors along with their key target genes suggests that diurnal nuclear receptor expression may contribute to established rhythms in metabolic physiology and that nuclear receptors may be involved in coupling peripheral circadian clocks to divergent metabolic outputs. Conversely, nuclear receptors may serve peripheral clock input pathways, integrating signals from the light-sensing central clock in the suprachiasmatic nucleus and other environmental cues, such as nutrients and xenobiotics. Interplay between the core circadian clock and nuclear receptors may define a large-scale signaling network that links biological timing to metabolic physiology.
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Affiliation(s)
- X Yang
- Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
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17
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Kharroubi I, Lee CH, Hekerman P, Darville MI, Evans RM, Eizirik DL, Cnop M. BCL-6: a possible missing link for anti-inflammatory PPAR-delta signalling in pancreatic beta cells. Diabetologia 2006; 49:2350-8. [PMID: 16896941 DOI: 10.1007/s00125-006-0366-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Accepted: 05/15/2006] [Indexed: 11/25/2022]
Abstract
AIMS/HYPOTHESIS Inflammatory mediators contribute to pancreatic beta cell death in type 1 diabetes. Beta cells respond to cytokine exposure by activating gene networks that alter cellular metabolism, induce chemokine release (thereby increasing insulitis), and cause apoptosis. We have previously shown by microarray analysis that exposure of INS-1E cells to IL-1beta + IFN-gamma induces the transcription factor peroxisome proliferator-activated receptor (Ppar)-delta and several of its target genes. PPAR-delta controls cellular lipid metabolism and is a major regulator of inflammatory responses. We therefore examined the role of PPAR-delta in cytokine-treated beta cells. MATERIALS AND METHODS Primary beta cells that had been purified by fluorescence-activated cell sorting and INS-1E cells were cultured in the presence of the cytokines TNF-alpha, IL-1beta, or IL-1beta + IFN-gamma, or the synthetic PPAR-delta agonist GW501516. Gene expression was analysed by real-time PCR. PPAR-delta, monocyte chemoattractant protein (MCP-1, now known as CCL2) promoter and NF-kappaB activity were determined by luciferase reporter assays. RESULTS Exposure of primary beta cells or INS-1E cells to cytokines induced Ppar-delta mRNA expression and PPAR-delta-dependent CD36, lipoprotein lipase, acyl CoA synthetase and adipophilin mRNAs. Cytokines and the PPAR-delta agonist GW501516 also activated a PPAR-delta response element reporter in beta cells. Unlike immune cells, neither INS-1E nor beta cells expressed the transcriptional repressor B-cell lymphoma-6 (BCL-6). As a consequence, PPAR-delta activation by GW501516 did not decrease cytokine-induced Mcp-1 promoter activation or mRNA expression, as reported for macrophages. Transient transfection with a BCL-6 expression vector markedly reduced Mcp-1 promoter and NF-kappaB activities in beta cells. CONCLUSIONS/INTERPRETATION Cytokines activate the PPAR-delta gene network in beta cells. This network does not, however, regulate the pro-inflammatory response to cytokines because beta cells lack constitutive BCL-6 expression. This may render beta cells particularly susceptible to propagating inflammation in type 1 diabetes.
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Affiliation(s)
- I Kharroubi
- Laboratory of Experimental Medicine, Université Libre de Bruxelles, CP-618, 808 Route de Lennik, Brussels, 1070, Belgium
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18
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Ho MW, Dhariwal DK, Chandrasekhar J, Patton DW, Silvester KC, Sadiq S, Evans RM. Use of interventional radiology in the management of mediastinitis of odontogenic origin. Br J Oral Maxillofac Surg 2005; 44:538-42. [PMID: 16233941 DOI: 10.1016/j.bjoms.2005.09.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2005] [Revised: 08/10/2005] [Accepted: 09/16/2005] [Indexed: 11/20/2022]
Abstract
Descending necrotising mediastinitis is a rare complication of odontogenic infection. The key to diagnosis is to maintain a high index of suspicion when antibiotics and adequate surgical drainage do not lead to resolution of symptoms. Open thoracic operation to drain mediastinal collections is potentially lethal and interventional radiological techniques are thought to reduce mortality. We report the use of interventional radiology in the diagnosis, monitoring and treatment of this condition and illustrate our experience with three case reports.
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Affiliation(s)
- M W Ho
- Undergraduate Medicine Department, University of Manchester (Keele), Manchester, UK.
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19
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Abstract
In this retrospective analysis of 443 Alzheimer disease (AD) patients from a 30-week tacrine trial, change in Alzheimer's Disease Assessment Scale score from baseline to final value was significantly associated with a total serum cholesterol/APOE genotype interaction. Disease progression in the no-APOE epsilon4 allele/high-cholesterol subgroup was greater than in the normal-cholesterol subgroups with or without epsilon4. Cholesterol levels and APOE genotype may interact to affect AD progression. The results are consistent with preclinical data on cholesterol's effects in AD.
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Affiliation(s)
- R M Evans
- Department of Neurology, Indiana University School of Medicine, Indianapolis, USA.
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20
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Rankin S, Blunt DM, Evans RM, Cook GJR. Picture quiz. Imaging 2003. [DOI: 10.1259/img.15.3.150156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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21
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22
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McClelland D, Evans RM, Abidin I, Sharma S, Choudhry FZ, Jaspars M, Sepčić K, Scott RH. Irreversible and reversible pore formation by polymeric alkylpyridinium salts (poly-APS) from the sponge Reniera sarai. Br J Pharmacol 2003; 139:1399-408. [PMID: 12922926 PMCID: PMC1573973 DOI: 10.1038/sj.bjp.0705374] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. In this study, we investigated the electrophysiological actions of a high molecular weight fraction, predominantly containing two polymeric 1,3-alkylpyridinium salts (poly-APS) of 5.5 and approximately 19 kDa isolated from the marine sponge Reniera sarai. The biological properties of poly-APS are of particular interest because this preparation may be used to deliver macromolecules into the intracellular environment without producing long-term damage to cells. Poly-APS (50-0.05 micro g ml(-1)) was applied to cultured dorsal root ganglion neurones or HEK 293 cells and changes in cell membrane properties were measured using whole-cell patch-clamp recording and fura-2 Ca(2+) imaging. 2. Poly-APS (50 micro g ml(-1)) evoked irreversible depolarisations in membrane potential and reductions in input resistance. However, doses of 5 micro g ml(-1) and less produced reversible effects on these cell membrane characteristics and on Ca(2+) permeability. 3. At 0.05 micro g ml(-1), poly-APS could robust transient increases in Ca(2+) permeability without damaging the neurones or subsequently attenuating Ca(2+) entry through voltage-activated channels. 4. Bathing cells in NaCl-based extracellular medium containing 1.5 mM zinc attenuated the irreversible and reversible effects of poly-APS on membrane properties (membrane potential, input resistance and whole-cell currents). In both DRG neurones and HEK 293 cells, zinc attenuated Ca(2+) entry evoked by poly-APS. These effects of zinc were only observed if zinc was continually present during poly-APS application. However, zinc failed to attenuate the actions of poly-APS if it was applied after the sponge toxin preparation had evoked changes in membrane properties. 5. In conclusion, the pore-forming preparation poly-APS can have dose-dependent interactions with cell membranes and at low doses these can be reversible. Additionally, the interactions between poly-APS and cell membranes could be attenuated by zinc.
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Affiliation(s)
- D McClelland
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD
| | - R M Evans
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD
| | - I Abidin
- Biophysics Department, Faculty of Medicine, Akdeniz University, 07070 Arapsuyu, Antalya, Turkey
| | - S Sharma
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD
| | - F Z Choudhry
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD
| | - M Jaspars
- Marine Natural Products Laboratory, Department of Chemistry, University of Aberdeen, Old Aberdeen AB24 3UE
| | - K Sepčić
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000 Ljubljana, Slovenia
| | - R H Scott
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD
- Author for correspondence:
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23
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Sonoda J, Rosenfeld JM, Xu L, Evans RM, Xie W. A nuclear receptor-mediated xenobiotic response and its implication in drug metabolism and host protection. Curr Drug Metab 2003; 4:59-72. [PMID: 12570746 DOI: 10.2174/1389200033336739] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Regulation of the Phase I CYP enzymes and Phase II conjugating enzymes is implicated in both drug metabolism and drug-drug interactions. Moreover, the elimination of numerous xenobiotic and endobiotic toxic chemicals also requires a concerted function of Phase I and II enzymes, as well as the membrane spanning drug transporters. The genes that encode these enzymes and transporters are inducible by numerous xenobiotics, yet the inducibility shows clear species specificity. In the last 3-4 years, orphan nuclear receptors (NRs) such as PXR, CAR, and FXR have been established as species-specific xeno-sensors that regulate the expression of Phase I and II enzymes, as well as selected drug transporters. This transcriptional regulation is achieved by binding of these xenobiotic receptors to the NR response elements found within the promoter regions of target genes. The identification of NRs as xenosensors represents a major step forward in understanding the genetic mechanisms controlling the expression of drug metabolizing enzymes. The establishment of NR-mediated and mechanism-guided xenobiotic screening systems by using cultured cells or genetically engineered mouse models has not only advanced our understanding of the molecular complexity of this drug-induced xenobiotic response, but has also provided in vitro and in vivo platforms to facilitate the development of safer drugs.
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Affiliation(s)
- J Sonoda
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, 3501 Terrace Street, Pittsburgh, PA 15213, USA
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24
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Abstract
Two related nuclear receptors, the pregnane X receptor (PXR) and the constitutive androstane receptor (CAR), act as xenobiotic sensors that protect the body from a multitude of foreign chemicals (xenobiotics) and play a central role in the metabolism and clearance of steroids and toxic endogenous lipids (endobiotics). A structurally diverse array of chemicals including pharmaceutical drugs, steroids, herbal extracts, and pesticides activate PXR or CAR. This activation results in induction of overlapping, but yet distinct drug clearance pathways consisting of cytochrome P450 enzymes, conjugating enzymes, drug transporters, and other related proteins. Similar pathways are also utilized to protect the body from toxic compounds of endogenous origin. Thus, the xenobiotic regulatory circuit contributes both to drug-drug and food-drug interactions as well as endocrine disruption. Consistent with the notion that xenobiotic receptors regulate drug clearance, single nucleotide polymorphisms (SNPs) in either the receptors themselves or receptor-binding sites in the regulatory region of genes encoding metabolic enzymes appear to contribute to the polymorphic expression of components of drug clearance pathways. Together, the xenobiotic receptors PXR and CAR confer metabolic immunity via the ability to control an integrated array of target genes.
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Affiliation(s)
- J. Sonoda
- 1Howard Hughes Medical Institute, Gene Expression Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - R. M. Evans
- 1Howard Hughes Medical Institute, Gene Expression Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
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25
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26
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27
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28
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Abstract
We describe a molecular switch based on the controlled methylation of nucleosome and the transcriptional cofactors, the CREB-binding proteins (CBP)/p300. The CBP/p300 methylation site is localized to an arginine residue that is essential for stabilizing the structure of the KIX domain, which mediates CREB recruitment. Methylation of KIX by coactivator-associated arginine methyltransferase 1 (CARM1) blocks CREB activation by disabling the interaction between KIX and the kinase inducible domain (KID) of CREB. Thus, CARM1 functions as a corepressor in cyclic adenosine monophosphate signaling pathway via its methyltransferase activity while acting as a coactivator for nuclear hormones. These results provide strong in vivo and in vitro evidence that histone methylation plays a key role in hormone-induced gene activation and define cofactor methylation as a new regulatory mechanism in hormone signaling.
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Affiliation(s)
- W Xu
- Gene Expression Laboratory, Department of Biological Chemistry, University of California Davis Cancer Center/Basic Science, Sacramento, CA 95817, USA
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29
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Abstract
Cholesterol, fatty acids, fat-soluble vitamins, and other lipids present in our diets are not only nutritionally important but serve as precursors for ligands that bind to receptors in the nucleus. To become biologically active, these lipids must first be absorbed by the intestine and transformed by metabolic enzymes before they are delivered to their sites of action in the body. Ultimately, the lipids must be eliminated to maintain a normal physiological state. The need to coordinate this entire lipid-based metabolic signaling cascade raises important questions regarding the mechanisms that govern these pathways. Specifically, what is the nature of communication between these bioactive lipids and their receptors, binding proteins, transporters, and metabolizing enzymes that links them physiologically and speaks to a higher level of metabolic control? Some general principles that govern the actions of this class of bioactive lipids and their nuclear receptors are considered here, and the scheme that emerges reveals a complex molecular script at work.
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Affiliation(s)
- A Chawla
- Howard Hughes Medical Institute, Gene Expression Laboratory, The Salk Institute for Biological Studies, Post Office Box 85800, San Diego, CA 92186-5800, USA
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30
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Abstract
It has been 10 years since the seminal discovery that a mutant form of a retinoid acid receptor (RARalpha) is associated with acute promyelocytic leukemia (APL). This finding, coupled with the remarkable success of retinoic acid (RA), the natural ligand of RARalpha, in the treatment of APL, has made APL a unique model system in the study of oncogenic conversion of transcription factors in hematological malignancies. Indeed, subsequent basic and clinical studies showed that chromosomal translocation involving the RARalpha gene is the cytogenetic hallmark of APL and that these mutant forms of RARs are the oncogenes in APL that interfere with the proliferation and differentiation pathways controlled by both RAR and their fusion partners. However, it was not until recently that the role of aberrant transcriptional regulation in the pathogenesis of APL was revealed. In this review, we summarize the biochemical and biological mechanisms of transcriptional regulation by mutant RARs and their corresponding wild-type fusion partner PML and PLZF. These studies have been instrumental in our understanding of the process of leukemogenesis in general and have laid the scientific foundation for the novel concept of transcription therapy in the treatment of human cancer.
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MESH Headings
- Cell Differentiation/genetics
- Cell Division/genetics
- Cell Nucleus Structures/metabolism
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Gene Expression Regulation, Leukemic
- Gene Silencing
- Humans
- Kruppel-Like Transcription Factors
- Leukemia, Promyelocytic, Acute/genetics
- Leukemia, Promyelocytic, Acute/metabolism
- Macromolecular Substances
- Mutation
- Neoplasm Proteins/genetics
- Neoplasm Proteins/metabolism
- Nuclear Proteins
- Oncogene Proteins, Fusion/genetics
- Oncogene Proteins, Fusion/metabolism
- Organelles/metabolism
- Promyelocytic Leukemia Protein
- Promyelocytic Leukemia Zinc Finger Protein
- Receptors, Retinoic Acid/genetics
- Receptors, Retinoic Acid/metabolism
- Retinoic Acid Receptor alpha
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Translocation, Genetic
- Tumor Suppressor Proteins
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Affiliation(s)
- R J Lin
- Howard Hughes Medical Institute, Gene Expression Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California, CA 92037, USA
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31
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Affiliation(s)
- W Xie
- Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
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32
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Misner DL, Jacobs S, Shimizu Y, de Urquiza AM, Solomin L, Perlmann T, De Luca LM, Stevens CF, Evans RM. Vitamin A deprivation results in reversible loss of hippocampal long-term synaptic plasticity. Proc Natl Acad Sci U S A 2001; 98:11714-9. [PMID: 11553775 PMCID: PMC58795 DOI: 10.1073/pnas.191369798] [Citation(s) in RCA: 200] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Despite its long history, the central effects of progressive depletion of vitamin A in adult mice has not been previously described. An examination of vitamin-deprived animals revealed a progressive and ultimately profound impairment of hippocampal CA1 long-term potentiation and a virtual abolishment of long-term depression. Importantly, these losses are fully reversible by dietary vitamin A replenishment in vivo or direct application of all trans-retinoic acid to acute hippocampal slices. We find retinoid responsive transgenes to be highly active in the hippocampus, and by using dissected explants, we show the hippocampus to be a site of robust synthesis of bioactive retinoids. In aggregate, these results demonstrate that vitamin A and its active derivatives function as essential competence factors for long-term synaptic plasticity within the adult brain, and suggest that key genes required for long-term potentiation and long-term depression are retinoid dependent. These data suggest a major mental consequence for the hundreds of millions of adults and children who are vitamin A deficient.
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Affiliation(s)
- D L Misner
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, Howard Hughes Medical Institute, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
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33
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Renth F, Poon WC, Evans RM. Phase transition kinetics in colloid-polymer mixtures at triple coexistence: kinetic maps from free-energy landscapes. Phys Rev E Stat Nonlin Soft Matter Phys 2001; 64:031402. [PMID: 11580334 DOI: 10.1103/physreve.64.031402] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2001] [Indexed: 05/23/2023]
Abstract
We report a detailed experimental study of the kinetics of separation into coexisting gas, liquid, and crystal phases in a colloid-polymer mixture. Distinct kinetic regimes are identified, and interpreted in terms of the underlying "free-energy landscape" of the system.
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Affiliation(s)
- F Renth
- Department of Physics and Astronomy, The University of Edinburgh, Mayfield Road, Edinburgh, EH9 3JZ, Scotland
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Evans RM, Poon WC, Renth F. Classification of ordering kinetics in three-phase systems. Phys Rev E Stat Nonlin Soft Matter Phys 2001; 64:031403. [PMID: 11580335 DOI: 10.1103/physreve.64.031403] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2001] [Indexed: 05/23/2023]
Abstract
Though equations of motion containing transport coefficients are required to quantitatively predict the phase-ordering dynamics of any given system, a great deal can be gleaned just from the shape of the free-energy landscape. We demonstrate how to extract the most information concerning phase-ordering phenomenology from a knowledge of a system's free-energy function, or phase diagram. Many putative pathways to equilibrium can be ruled out on the grounds of the second law of thermodynamics. In some parts of the phase diagram, these considerations are sufficient to completely determine the phase-ordering process without ever having to calculate a transport coefficient, even when three phases are present. The results include a large number of regions of the phase diagram with distinct phase-ordering kinetics, and some surprisingly elaborate routes to the equilibrium state. A process is found whereby a crystalline condensation nucleus becomes coated with a shell of gas, buffering it from a majority metastable liquid phase. Our results, based on thermodynamic arguments, are supported by numerical solution of model B, which describes diffusive phase-ordering kinetics. Some of our predictions are tested against experimental observations of colloid-polymer mixtures, described in more detail in the preceding paper [F. Renth, W. C. K. Poon, and R. M. L. Evans, Phys. Rev. E 64, 031402 (2001)]. A compact notation is developed to represent intricate phase-ordering pathways.
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Affiliation(s)
- R M Evans
- Department of Physics and Astronomy, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, Scotland, United Kingdom
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35
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Evans RM. Herbal medicine in neuropsychiatry. Aust Fam Physician 2001; 30:735. [PMID: 11681140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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36
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Evans RM, Holmes CB. Diffusive growth of polydisperse hard-sphere crystals. Phys Rev E Stat Nonlin Soft Matter Phys 2001; 64:011404. [PMID: 11461254 DOI: 10.1103/physreve.64.011404] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2001] [Indexed: 05/23/2023]
Abstract
Unlike atoms, colloidal particles are not identical, but can only be synthesised within a finite size tolerance. Colloids are therefore polydisperse, i.e., mixtures of infinitely many components with sizes drawn from a continuous distribution. We model the crystallization of hard-sphere colloids (with/without attractions) from an initially amorphous phase. Although the polydisperse hard-sphere phase diagram has been widely studied, it is not straightforwardly applicable to real colloidal crystals, since they are inevitably out of equilibrium. The process by which colloidal crystals form determines the size distribution of the particles that comprise them. Once frozen into the crystal lattice, the particles are caged so that the composition cannot subsequently relax to the equilibrium optimum. We predict that the mean size of colloidal particles incorporated into a crystal is smaller than anticipated by equilibrium calculations. This is because small particles diffuse fastest and therefore arrive at the crystal in disproportionate abundance.
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Affiliation(s)
- R M Evans
- Department of Physics and Astronomy, The University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
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37
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Abstract
The overlapping expression profile of MEF2 and the class-II histone deacetylase, HDAC7, led us to investigate the functional interaction and relationship between these regulatory proteins. HDAC7 expression inhibits the activity of MEF2 (-A, -C, and -D), and in contrast MyoD and Myogenin activities are not affected. Glutathione S-transferase pulldown and immunoprecipitation demonstrate that the repression mechanism involves direct interactions between MEF2 proteins and HDAC7 and is associated with the ability of MEF2 to interact with the N-terminal 121 amino acids of HDAC7 that encode repression domain 1. The MADS domain of MEF2 mediates the direct interaction of MEF2 with HDAC7. MEF2 inhibition by HDAC7 is dependent on the N-terminal repression domain and surprisingly does not involve the C-terminal deacetylase domain. HDAC7 interacts with CtBP and other class-I and -II HDACs suggesting that silencing of MEF2 activity involves corepressor recruitment. Furthermore, we show that induction of muscle differentiation by serum withdrawal leads to the translocation of HDAC7 from the nucleus into the cytoplasm. This work demonstrates that HDAC7 regulates the function of MEF2 proteins and suggests that this class-II HDAC regulates this important transcriptional (and pathophysiological) target in heart and muscle tissue. The nucleocytoplasmic trafficking of HDAC7 and other class-II HDACs during myogenesis provides an ideal mechanism for the regulation of HDAC targets during mammalian development and differentiation.
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Affiliation(s)
- U Dressel
- University of Queensland, Institute for Molecular Bioscience, Centre for Molecular and Cellular Biology, Ritchie Research Laboratories, B402A, St. Lucia 4072, Queensland, Australia
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38
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Affiliation(s)
- P Ordentlich
- Howard Hughes Medical Institute, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
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39
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Shi Y, Downes M, Xie W, Kao HY, Ordentlich P, Tsai CC, Hon M, Evans RM. Sharp, an inducible cofactor that integrates nuclear receptor repression and activation. Genes Dev 2001; 15:1140-51. [PMID: 11331609 PMCID: PMC312688 DOI: 10.1101/gad.871201] [Citation(s) in RCA: 257] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2000] [Accepted: 03/01/2001] [Indexed: 11/25/2022]
Abstract
A yeast two-hybrid screen using the conserved carboxyl terminus of the nuclear receptor corepressor SMRT as a bait led to the isolation of a novel human gene termed SHARP (SMRT/HDAC1 Associated Repressor Protein). SHARP is a potent transcriptional repressor whose repression domain (RD) interacts directly with SMRT and at least five members of the NuRD complex including HDAC1 and HDAC2. In addition, SHARP binds to the steroid receptor RNA coactivator SRA via an intrinsic RNA binding domain and suppresses SRA-potentiated steroid receptor transcription activity. Accordingly, SHARP has the capacity to modulate both liganded and nonliganded nuclear receptors. Surprisingly, the expression of SHARP is itself steroid inducible, suggesting a simple feedback mechanism for attenuation of the hormonal response.
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Affiliation(s)
- Y Shi
- Howard Hughes Medical Institute, The Salk Institute for Biological Studies, Gene Expression Laboratory, La Jolla, California 92037, USA
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Abstract
The role of histone acetylation as a key mechanism of transcriptional regulation has been well established. Recent advances suggest that histone acetyltransferases also play important roles in histone-modulated processes such as DNA replication, recombination and repair. In addition, acetylation of transcriptional cofactors and other proteins is an efficient means of regulating a diverse range of molecular interactions. As new histone acetyltransferases and substrates are rapidly emerging, it is becoming apparent that protein acetylation may rival phosphorylation as a mechanism to transduce cellular regulatory signals.
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Affiliation(s)
- H Chen
- Department of Biological Chemistry, UC Davis Cancer Center/Basic Science Program, University of California at Davis, Sacramento, California 95817, USA.
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Mundasad MV, Novack GD, Allgood VE, Evans RM, Gorden JC, Yerxa BR. Ocular safety of INS365 ophthalmic solution: a P2Y(2) agonist in healthy subjects. J Ocul Pharmacol Ther 2001; 17:173-9. [PMID: 11324984 DOI: 10.1089/10807680151125519] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The purpose of this study was to evaluate the ocular safety and tolerability of the P2Y(2) receptor agonist, INS365, when applied as eye drops in normal human subjects. This study was a double-masked, placebo-controlled, randomized, within subject paired-comparison, dose-escalation study in five cohorts of ten healthy subjects. The concentrations of INS365 ophthalmic solution were 0.5, 1.0, 2.0, and 5.0% given three times over six hours. Safety was assessed by general and ophthalmic examination and symptomatology. Unanesthetized Schirmer tests were performed in the last cohort of 10 subjects to evaluate the acute effects of INS365 on tear secretion. There were no significant differences in the number of subjects with ocular events reported in placebo-treated eyes compared to INS365-treated eyes. Two adverse events were possibly related to INS365: painless blepharospasm and an increase in lacrimation after 5.0% INS365 instillation. Unanesthetized Schirmer testing showed no acute effects of INS365 on tear secretion, compared to its vehicle, in healthy subjects, in which reflex tearing often produced maximal Schirmer values. INS365 ophthalmic solution was well-tolerated when administered by ocular instillation. Stimulation of ocular surface P2Y(2) receptors was not associated with ocular tolerability issues in healthy subjects.
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Ghbeish N, Tsai CC, Schubiger M, Zhou JY, Evans RM, McKeown M. The dual role of ultraspiracle, the Drosophila retinoid X receptor, in the ecdysone response. Proc Natl Acad Sci U S A 2001; 98:3867-72. [PMID: 11274407 PMCID: PMC31144 DOI: 10.1073/pnas.061437798] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Drosophila homolog of the retinoid X receptor, ultraspiracle (USP), heterodimerizes with the ecdysone receptor (EcR) to form a functional complex that mediates the effects of the steroid molting hormone ecdysone by activating and repressing expression of ecdysone response genes. As with other retinoid X receptor heterodimers, EcR/USP affects gene transcription in a ligand-modulated manner. We used in vivo, cell culture, and biochemical approaches to analyze the functions of two usp alleles, usp(3) and usp(4), which encode stable proteins with defective DNA-binding domains. We observed that USP is able to activate as well as repress the Z1 isoform of the ecdysone-responsive broad complex (BrC-Z1). Activation of BrC-Z1 as well as EcR, itself an ecdysone response gene, can be mediated by both the USP3 and USP4 mutant proteins. USP3 and USP4 also activate an ecdysone-responsive element, hsp27EcRE, in cultured cells. These results differ from the protein null allele, usp(2), which is unable to mediate activation [Schubiger, M. & Truman, J. W. (2000) Development 127, 1151--1159]. BrC-Z1 repression is compromised in all three usp alleles, suggesting that repression involves the association of USP with DNA. Our results distinguish two mechanisms by which USP modulates the properties of EcR: one that involves the USP DNA-binding domain and one that can be achieved solely through the ligand-binding domain. These newly revealed properties of USP might implicate similar properties for retinoid X receptor.
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Affiliation(s)
- N Ghbeish
- Department of Biology, University of California at San Diego, La Jolla, CA 92093, USA
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43
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Abstract
De novo expression of vimentin, GFAP or peripherin leads to the assembly of an extended intermediate filament network in intermediate filament-free SW13/cl.2 cells. Desmin, in contrast, does not form extended filament networks in either SW13/cl.2 or intermediate filament-free mouse fibroblasts. Rather, desmin formed short thickened filamentous structures and prominent spot-like cytoplasmic aggregates that were composed of densely packed 9–11 nm diameter filaments. Analysis of stably transfected cell lines indicates that the inability of desmin to form extended networks is not due to a difference in the level of transgene expression. Nestin, paranemin and synemin are large intermediate filament proteins that coassemble with desmin in muscle cells. Although each of these large intermediate filament proteins colocalized with desmin when coexpressed in SW-13 cells, expression of paranemin, but not synemin or nestin, led to the formation of an extended desmin network. A similar rescue of desmin network organization was observed when desmin was coexpressed with vimentin, which coassembles with desmin, or with keratins, which formed a distinct filament network. These studies demonstrate that desmin filaments differ in their organizational properties from the other vimentin-like intermediate filament proteins and appear to depend upon coassembly with paranemin, at least when they are expressed in non-muscle cells, in order to form an extended filament network.
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Affiliation(s)
- S C Schweitzer
- Department of Pathology, University of Colorado Health Sciences Center, Denver, Colorado, USA
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Xie W, Radominska-Pandya A, Shi Y, Simon CM, Nelson MC, Ong ES, Waxman DJ, Evans RM. An essential role for nuclear receptors SXR/PXR in detoxification of cholestatic bile acids. Proc Natl Acad Sci U S A 2001; 98:3375-80. [PMID: 11248086 PMCID: PMC30661 DOI: 10.1073/pnas.051014398] [Citation(s) in RCA: 556] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/08/2001] [Indexed: 02/07/2023] Open
Abstract
Hepatic hydroxylation is an essential step in the metabolism and excretion of bile acids and is necessary to avoid pathologic conditions such as cholestasis and liver damage. In this report, we demonstrate that the human xenobiotic receptor SXR (steroid and xenobiotic receptor) and its rodent homolog PXR (pregnane X receptor) serve as functional bile acid receptors in both cultured cells and animals. In particular, the secondary bile acid derivative lithocholic acid (LCA) is highly hepatotoxic and, as we show here, a metabolic substrate for CYP3A hydroxylation. By using combinations of knockout and transgenic animals, we show that activation of SXR/PXR is necessary and sufficient to both induce CYP3A enzymes and confer resistance to toxicity by LCA, as well as other xenotoxicants such as tribromoethanol and zoxazolamine. Therefore, we establish SXR and PXR as bile acid receptors and a role for the xenobiotic response in the detoxification of bile acids.
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Affiliation(s)
- W Xie
- Howard Hughes Medical Institute, Gene Expression Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
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45
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Hendrie HC, Ogunniyi A, Hall KS, Baiyewu O, Unverzagt FW, Gureje O, Gao S, Evans RM, Ogunseyinde AO, Adeyinka AO, Musick B, Hui SL. Incidence of dementia and Alzheimer disease in 2 communities: Yoruba residing in Ibadan, Nigeria, and African Americans residing in Indianapolis, Indiana. JAMA 2001; 285:739-47. [PMID: 11176911 DOI: 10.1001/jama.285.6.739] [Citation(s) in RCA: 276] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Alzheimer disease (AD) represents a major and increasing public health problem. If populations were identified with significantly lower or higher incidence rates of AD, the search for risk factors in the genesis of AD could be greatly enhanced. OBJECTIVE To compare incidence rates of dementia and AD in 2 diverse, elderly community-dwelling populations. DESIGN The Indianapolis-Ibadan Dementia Project, a longitudinal, prospective population-based study consisting of a baseline survey (1992-1993) and 2 subsequent follow-up waves after 2 years (1994-1995) and 5 years (1997-1998). Each wave followed a 2-stage design, with an in-home screening interview followed by a full diagnostic workup of a subsample of participants based on screening performance. SETTING AND PARTICIPANTS A total of 2459 community-dwelling Yoruba residents of Ibadan, Nigeria, without dementia, and 2147 community-dwelling African American residents of Indianapolis, Ind, without dementia (all aged 65 years or older). The cohorts were followed up for a mean of 5.1 years and 4.7 years, respectively. MAIN OUTCOME MEASURES Incident cases of dementia and AD in each of the 2 populations. RESULTS The age-standardized annual incidence rates were significantly lower among Yoruba than among African Americans for dementia (Yoruba, 1.35% [95% confidence interval [CI], 1.13%-1.56%]; African Americans, 3.24% [95% CI, 2.11%-4.38%]) and for AD (Yoruba, 1.15% [95% CI, 0.96%-1.35%]; African Americans, 2.52% [95% CI, 1.40%-3.64%]). CONCLUSION This is the first report of incidence rate differences for dementia and AD in studies of 2 populations from nonindustrialized and industrialized countries using identical methods and the same group of investigators in both sites. Further explorations of these population differences may identify potentially modifiable environmental or genetic factors to account for site differences in dementia and AD.
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Affiliation(s)
- H C Hendrie
- Department of Psychiatry, Indiana University School of Medicine, 541 Clinical Dr, Room 394A, Indianapolis, IN 46202, USA.
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Clayton GM, Peak-Chew SY, Evans RM, Schwabe JW. The structure of the ultraspiracle ligand-binding domain reveals a nuclear receptor locked in an inactive conformation. Proc Natl Acad Sci U S A 2001; 98:1549-54. [PMID: 11171988 PMCID: PMC29294 DOI: 10.1073/pnas.98.4.1549] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Ultraspiracle (USP) is the invertebrate homologue of the mammalian retinoid X receptor (RXR). RXR plays a uniquely important role in differentiation, development, and homeostasis through its ability to serve as a heterodimeric partner to many other nuclear receptors. RXR is able to influence the activity of its partner receptors through the action of the ligand 9-cis retinoic acid. In contrast to RXR, USP has no known high-affinity ligand and is thought to be a silent component in the heterodimeric complex with partner receptors such as the ecdysone receptor. Here we report the 2.4-A crystal structure of the USP ligand-binding domain. The structure shows that a conserved sequence motif found in dipteran and lepidopteran USPs, but not in mammalian RXRs, serves to lock USP in an inactive conformation. It also shows that USP has a large hydrophobic cavity, implying that there is almost certainly a natural ligand for USP. This cavity is larger than that seen previously for most other nuclear receptors. Intriguingly, this cavity has partial occupancy by a bound lipid, which is likely to resemble the natural ligand for USP.
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Affiliation(s)
- G M Clayton
- Medical Research Council, Laboratory of Molecular Biology, Cambridge CB2 2QH, United Kingdom
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47
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Chawla A, Barak Y, Nagy L, Liao D, Tontonoz P, Evans RM. PPAR-gamma dependent and independent effects on macrophage-gene expression in lipid metabolism and inflammation. Nat Med 2001; 7:48-52. [PMID: 11135615 DOI: 10.1038/83336] [Citation(s) in RCA: 858] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is highly expressed in lipid-accumulating macrophages of the coronary artery. In light of this, the wide-spread clinical use of thiazolidinediones (TZDs) in the treatment of type II diabetes raises concerns about the role of PPAR-gamma in macrophage function and disease progression. To define the role of PPAR-gamma in macrophage biology, we used homologous recombination to create embryonic stem cells that were homozygous for a null mutation in the PPAR-gamma gene. We demonstrate here that PPAR-gamma is neither essential for nor substantially affects the development of the macrophage lineage both in vitro and in vivo. In contrast, we show it is an important regulator of the scavenger receptor CD36, which has been genetically linked to lipid accumulation in macrophages. Both 15-deoxy-Delta12,14prostaglandin J2 and thiazolidinediones have anti-inflammatory effects that are independent of PPAR-gamma. We show that PPAR-gamma is required for positive effects of its ligands in modulating macrophage lipid metabolism, but that inhibitory effects on cytokine production and inflammation may be receptor independent.
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Affiliation(s)
- A Chawla
- The Salk Institute for Biological Studies, Howard Hughes Medical Institute, La Jolla, California 90237, and Division of Endocrinology and Metabolism, University of California, San Diego, California 92093, USA
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48
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Chawla A, Boisvert WA, Lee CH, Laffitte BA, Barak Y, Joseph SB, Liao D, Nagy L, Edwards PA, Curtiss LK, Evans RM, Tontonoz P. A PPAR gamma-LXR-ABCA1 pathway in macrophages is involved in cholesterol efflux and atherogenesis. Mol Cell 2001; 7:161-71. [PMID: 11172721 DOI: 10.1016/s1097-2765(01)00164-2] [Citation(s) in RCA: 1041] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Previous work has implicated PPAR gamma in the regulation of CD36 expression and macrophage uptake of oxidized LDL (oxLDL). We provide evidence here that in addition to lipid uptake, PPAR gamma regulates a pathway of cholesterol efflux. PPAR gamma induces ABCA1 expression and cholesterol removal from macrophages through a transcriptional cascade mediated by the nuclear receptor LXR alpha. Ligand activation of PPAR gamma leads to primary induction of LXR alpha and to coupled induction of ABCA1. Transplantation of PPAR gamma null bone marrow into LDLR -/- mice results in a significant increase in atherosclerosis, consistent with the hypothesis that regulation of LXR alpha and ABCA1 expression is protective in vivo. Thus, we propose that PPAR gamma coordinates a complex physiologic response to oxLDL that involves particle uptake, processing, and cholesterol removal through ABCA1.
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Affiliation(s)
- A Chawla
- Salk Institute for Biological Studies, Howard Hughes Medical Institute, La Jolla, CA 92037, USA
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Saez E, Nelson MC, Eshelman B, Banayo E, Koder A, Cho GJ, Evans RM. Identification of ligands and coligands for the ecdysone-regulated gene switch. Proc Natl Acad Sci U S A 2000; 97:14512-7. [PMID: 11114195 PMCID: PMC18950 DOI: 10.1073/pnas.260499497] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The ecdysone-inducible gene switch is a useful tool for modulating gene expression in mammalian cells and transgenic animals. We have identified inducers derived from plants as well as certain classes of insecticides that increase the versatility of this gene regulation system. Phytoecdysteroids share the favorable kinetics of steroids, but are inert in mammals. The gene regulation properties of one of these ecdysteroids have been examined in cell culture and in newly developed strains of ecdysone-system transgenic mice. Ponasterone A is a potent regulator of gene expression in cells and transgenic animals, enabling reporter genes to be turned on and off rapidly. A number of nonsteroidal insecticides have been identified that also activate the ecdysone system. Because the gene-controlling properties of the ecdysone switch are based on a heterodimer composed of a modified ecdysone receptor (VgEcR) and the retinoid X receptor (RXR), we have tested the effect of RXR ligands on the VgEcR/RXR complex. Used alone, RXR ligands display no activity on the ecdysone switch. However, when used in combination with a VgEcR ligand, RXR ligands dramatically enhance the absolute levels of induction. This property of the heterodimer has allowed the development of superinducer combinations that increase the dynamic range of the system.
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Affiliation(s)
- E Saez
- The Salk Institute for Biological Studies, Howard Hughes Medical Institute, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
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50
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Mohanty K, Gupta SK, Evans RM. Check radiography after fixation of hip fractures: is it necessary? J R Coll Surg Edinb 2000; 45:398-9. [PMID: 11153432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Technological advances in radiography in the form of image intensification has not only made internal fixation of femoral neck fracture much easier but these high resolution films can be saved as hard copies and can also be reversed into 'positives' at a later date. However, requesting routine post-operative check radiographs for these fractures are still a common practice. A retrospective study was carried out to compare the quality of image intensifier films with conventional post-operative radiographs. 79 sets of films were reviewed with particular reference to adequacy of fixation and possible joint penetration by the screws. No significant difference was noted between the two sets of films. We suggest that routine post-operative radiographs after femoral neck fracture fixation are unnecessary unless there is some clinical indication. This has significant implications in relation to patient discomfort, radiation exposure and cost-effectiveness.
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Affiliation(s)
- K Mohanty
- Department of Orthopaedics and Radiology, Morriston Hospital, Swansea, U.K
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