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Polkinghorne M, Akawi N, Badi I, Checa A, Kotanidis C, Akoumianakis I, Antonopoulos A, Krasopoulos G, Sayeed R, Walcot N, Channon K, Wheelock C, Antoniades C. Adipose tissue derived ceramides regulate myocardial redox state and predict cardiovascular outcomes. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.2897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Obesity is linked to both dysfunctional adipose tissue (AT) and heart failure, but the exact mechanisms mediating these associations are unknown. Although ceramides biosynthesis is dysregulated in obesity, their role as mediators of obesity-induced myocardial dysfunction is unclear.
Purpose
We investigate the causal role of AT-derived ceramides in the regulation of myocardial redox state and explore their role in predicting cardiovascular outcomes.
Methods
The study population included a total of 880 patients undergoing cardiac surgery. A panel of 20 sphingolipids was measured in plasma as well as in biopsies of subcutaneous AT (ScAT), thoracic AT (ThAT) and epicardial AT (EpAT) and their secretome, obtained from a subgroup of n=48. Myocardial redox state was measured using lucigenin chemiluminescence and the contribution of NOXs, uncoupled nitric oxide synthases and mitochondrial oxidases in O2•– production was quantified. The cohort was followed up for a median of 8.3 years. Genome-wide genetic analysis was done using the UK Biobank array. A total of 99,524 SNPs within 50kb of 110 genes involved in sphingolipid biosynthesis were analysed to identify genetic variants that could predict CVD outcomes using cis-Mendelian Randomisation. The underlying mechanisms were then explored further, using differentiated H9c2 cardiomyocytes in vitro and human right atrial tissue ex vivo.
Results
The production and secretion of C16:0-ceramide (CerC16) was higher in visceral AT (EpAT and ThAT) compared to ScAT (p<0.0001). Patients with high plasma levels of CerC16 and its derivative C16:0-glucosylceramide (GlcC16) had higher myocardial O2•– production vs those with low/int. levels (p<0.05 for both) (A). To test the causality of this association, we performed a targeted single-SNP analysis for the genetic prediction of GlcC16 levels demonstrating that rs112572487, an intronic variant in UGCG (an enzyme that catalyses glucosylceramide formation from ceramides), was the top hit (B). Indeed, those with the rs112572487 minor allele (G) displayed significantly increased myocardial NOX-derived O2•– (C) and plasma GlcC16 levels (D) vs those without. Exogenous CerC16 (20nM) induced NOX-derived O2•– production in H9c2 cardiomyocytes, an effect prevented by the UGCG inhibitor D-PDMP (E), suggesting that GlcC16 is a modifiable regulator of myocardial NOX-O2•–. Importantly, high plasma GlcC16 levels were associated with a higher risk of cardiac death and/or heart failure (adj. HR=2.128 [95% CI: 1.101, 4.115], p=0.025, for high vs low/int. levels), a relationship also seen with rs112572487 (F).
Conclusions
We demonstrate for the first time, that AT-derived ceramides are causally related with dysregulated myocardial redox signalling and adverse cardiovascular disease outcomes in patients with advanced atherosclerosis. As such, GlcC16 may be an important therapeutic target for the prevention and treatment of cardiovascular complications in obesity and diabetes.
Funding Acknowledgement
Type of funding sources: Foundation. Main funding source(s): The British Heart FoundationBritish Heart Foundation Chair Award
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Affiliation(s)
| | - N Akawi
- University of Oxford , Oxford , United Kingdom
| | - I Badi
- University of Oxford , Oxford , United Kingdom
| | - A Checa
- Karolinska Institute , Stockholm , Sweden
| | - C Kotanidis
- University of Oxford , Oxford , United Kingdom
| | | | | | | | - R Sayeed
- John Radcliffe Hospital , Oxford , United Kingdom
| | - N Walcot
- John Radcliffe Hospital , Oxford , United Kingdom
| | - K Channon
- University of Oxford , Oxford , United Kingdom
| | - C Wheelock
- Karolinska Institute , Stockholm , Sweden
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Kotanidis CP, Lockstone H, Polkinghorne M, Badi I, Akoumianakis I, Siddique M, Antonopoulos A, Evans T, Farid S, Srivastava V, Krasopoulos G, Sayeed R, Channon KM, Antoniades C. A human arterial transcriptomic signature predicts major adverse cardiac events and identifies novel, redox-related therapeutic targets within the vascular wall. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.1089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
The transcriptomic profile of the human vascular wall is implicated in a range of pathologies. RNA sequencing technologies allow for interrogation of gene expression patterns that are associated with clinical outcomes and can guide future research and drug development.
Purpose
To apply discovery network transcriptomics to internal mammary arteries (IMAs) obtained from patients undergoing cardiac surgery, in order to identify redox-related molecular pathways within the vascular wall that can be treated therapeutically.
Methods
Arm 1 included 377 patients in whom segments of IMA were used for ex-vivo quantification of NADPH-stimulated superoxide production by lucigenin-enhanced chemiluminescence. Arm 2 included 205 patients in whom bulk RNA sequencing was performed in RNA isolated from IMA, and the WGCNA package used for the analyses. The association with future incidence of major adverse cardiac events (MACE: cardiovascular death, non-fatal myocardial infarction, and stroke) was assessed using Cox regression models (adjusted for age, sex, hypertension, dyslipidaemia, diabetes mellitus, body mass index, smoking, and plasma TNFa).
Results
Over a median follow-up of 4.84 years [IQR: 2.03–7.14], 38 (11.2%) MACE occurred in Arm 1. High arterial NADPH-stimulated superoxide was independently associated with MACE risk (Adj. HR [95% CI]: 2.62 [1.13–6.07] high group, p=0.02). Unsupervised transcriptomic analysis in Arm 2 allowed identification of 10 coexpressed gene “modules”. Eigengenes summarising modular coexpression signatures were then correlated with NADPH-stimulated superoxide revealing the red module (a) as the most significant (rho=0.19, p=0.01). In survival analysis the red module showed significant correlation with MACE (Adj. HR [95% CI]: 1.40 [1.00–1.95] per SD, p=0.04). For an optimal cut-off, patients with high eigengene values for the red module showed a 4-fold higher risk of MACE (b), and significantly higher arterial oxidative stress (c). Enrichment analysis (performed with Enrichr) of genes in the red module revealed “Electron Transport Chain”, “Oxidative phosphorylation”, “Striated Muscle Contraction Pathway”, and “Glycolysis and Gluconeogenesis” amongst the top enriched pathways (d).
Conclusion
We present for the first time a novel human arterial transcriptomic signature reflecting changes in redox state, which identifies long-term cardiovascular risk. Targeting pathways in the vasculature related with the mitochondrial electron transport chain, the contractile mechanism, or glucose metabolism may lead to the development of novel therapeutics in cardiovascular disease.
Funding Acknowledgement
Type of funding sources: Foundation. Main funding source(s): EPSRC-EP/N509711/1-2119518British Heart Foundation Figure 1
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Affiliation(s)
| | - H Lockstone
- University of Oxford, Oxford, United Kingdom
| | | | - I Badi
- University of Oxford, Oxford, United Kingdom
| | | | - M Siddique
- University of Oxford, Oxford, United Kingdom
| | | | - T Evans
- University of Oxford, Oxford, United Kingdom
| | - S Farid
- Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - V Srivastava
- Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - G Krasopoulos
- Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - R Sayeed
- Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - K M Channon
- University of Oxford, Oxford, United Kingdom
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Klassen S, Carter AK, Evans DH, Ortman S, Stark MT, Loyless AA, Polkinghorne M, Heng P, Hill M, Wijker P, Niles-Weed J, Marriner GP, Pottier C, Fletcher RJ. Diachronic modeling of the population within the medieval Greater Angkor Region settlement complex. Sci Adv 2021; 7:eabf8441. [PMID: 33962951 PMCID: PMC8104873 DOI: 10.1126/sciadv.abf8441] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 03/22/2021] [Indexed: 06/12/2023]
Abstract
Angkor is one of the world's largest premodern settlement complexes (9th to 15th centuries CE), but to date, no comprehensive demographic study has been completed, and key aspects of its population and demographic history remain unknown. Here, we combine lidar, archaeological excavation data, radiocarbon dates, and machine learning algorithms to create maps that model the development of the city and its population growth through time. We conclude that the Greater Angkor Region was home to approximately 700,000 to 900,000 inhabitants at its apogee in the 13th century CE. This granular, diachronic, paleodemographic model of the Angkor complex can be applied to any ancient civilization.
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Affiliation(s)
- Sarah Klassen
- Department of Anthropology, University of British Columbia, Vancouver, BC, Canada.
- University of Oregon, 1585 E 13th Avenue, Eugene, OR 97403, USA
- Leiden University, Rapenburg 70, 2311 EZ Leiden, Netherlands
| | - Alison K Carter
- Department of Anthropology, University of Oregon, 308 Condon Hall, 1321 Kincaid Street, Eugene, OR 97403 USA
| | - Damian H Evans
- École française d'Extrême-Orient, 22 Avenue du Président Wilson, 75116 Paris, France
| | - Scott Ortman
- Institute of Behavioral Science, University of Colorado, Boulder, CO 80309, USA
| | - Miriam T Stark
- Department of Anthropology, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Alyssa A Loyless
- Department of Anthropology, Stanford University, Palo Alto, CA 94305, USA
| | | | - Piphal Heng
- Center for Southeast Asian Studies and Department of Anthropology, Northern Illinois University, DeKalb, IL 60115, USA
| | | | - Pelle Wijker
- École française d'Extrême-Orient, 22 Avenue du Président Wilson, 75116 Paris, France
| | - Jonathan Niles-Weed
- Courant Institute of Mathematical Sciences and Center for Data Science, New York University, New York, NY 10012, USA
| | - Gary P Marriner
- Casey & Lowe Archaeology and Heritage, Sydney, NSW 2040, Australia
| | - Christophe Pottier
- École française d'Extrême-Orient, 22 Avenue du Président Wilson, 75116 Paris, France
| | - Roland J Fletcher
- Department of Archaeology, University of Sydney, NSW 2006, Australia
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Polkinghorne M, Morton CA, Roberts A, Popelka-Filcoff RS, Sato Y, Vuthy V, Thammapreechakorn P, Stopic A, Grave P, Hein D, Vitou L. Consumption and exchange in Early Modern Cambodia: NAA of brown-glaze stoneware from Longvek, 15th-17th centuries. PLoS One 2019; 14:e0216895. [PMID: 31083691 PMCID: PMC6513050 DOI: 10.1371/journal.pone.0216895] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 04/30/2019] [Indexed: 11/18/2022] Open
Abstract
An evaluation of the geochemical characteristics of 102 storage jar sherds by k0-neutron activation analysis (k0-NAA) from archaeological contexts in Cambodia and reference samples from stoneware production centres in Thailand provides a new perspective on regional and global trade in mainland Southeast Asia. Identification of seven geochemical groups enables distinctions between production centres, and articulation of their role in trade between northern and central Thailand, South China and Cambodia. Storage jars from Thailand and South China are known in archaeological contexts worldwide because of their durability and intrinsic functional and cultural values. Evidenced by a novel application of k0-NAA, analogous stoneware sherds at Longvek connect the Cambodian capital to a global trading network. Additional proof of ceramics from an undocumented Cambodian kiln demonstrates the gradual and complex transition between the Angkorian past and the Early Modern period.
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Affiliation(s)
- Martin Polkinghorne
- Archaeology, Flinders University, Adelaide, South Australia, Australia
- * E-mail:
| | | | - Amy Roberts
- Archaeology, Flinders University, Adelaide, South Australia, Australia
| | | | - Yuni Sato
- Department of Planning and Coordination, The Nara National Research Institute for Cultural Properties, Nara, Nara Prefecture, Japan
| | - Voeun Vuthy
- Department of Archaeology and Prehistory, Ministry of Culture and Fine Arts, Phnom Penh, Phnom Penh, Cambodia
| | | | - Attila Stopic
- Reactor Irradiations, Radioisotopes and Radiotracers, Australian Nuclear Science and Technology Organisation, Lucas Heights, New South Wales, Australia
| | - Peter Grave
- Archaeology and Palaeoanthropology, University of New England, Armidale, New South Wales, Australia
| | - Don Hein
- Arthur M. Sackler Gallery and the Freer Gallery of Art, Washington, D.C., United States of America
| | - Leng Vitou
- Department of Archaeology and Prehistory, Ministry of Culture and Fine Arts, Phnom Penh, Phnom Penh, Cambodia
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Penny D, Hall T, Evans D, Polkinghorne M. Geoarchaeological evidence from Angkor, Cambodia, reveals a gradual decline rather than a catastrophic 15th-century collapse. Proc Natl Acad Sci U S A 2019; 116:4871-4876. [PMID: 30804175 PMCID: PMC6421400 DOI: 10.1073/pnas.1821460116] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Alternative models exist for the movement of large urban populations following the 15th-century CE abandonment of Angkor, Cambodia. One model emphasizes an urban diaspora following the implosion of state control in the capital related, in part, to hydroclimatic variability. An alternative model suggests a more complex picture and a gradual rather than catastrophic demographic movement. No decisive empirical data exist to distinguish between these two competing models. Here we show that the intensity of land use within the economic and administrative core of the city began to decline more than one century before the Ayutthayan invasion that conventionally marks the end of the Angkor Period. Using paleobotanical and stratigraphic data derived from radiometrically dated sediment cores extracted from the 12th-century walled city of Angkor Thom, we show that indicia for burning, forest disturbance, and soil erosion all decline as early as the first decades of the 14th century CE, and that the moat of Angkor Thom was no longer being maintained by the end of the 14th century. These data indicate a protracted decline in occupation within the economic and administrative core of the city, rather than an abrupt demographic collapse, suggesting the focus of power began to shift to urban centers outside of the capital during the 14th century.
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Affiliation(s)
- Dan Penny
- School of Geosciences, The University of Sydney, Sydney, NSW 2006, Australia;
| | - Tegan Hall
- School of Geosciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Damian Evans
- École Française d'Extrême-Orient, 75116 Paris, France
| | - Martin Polkinghorne
- Archaeology, College of Humanities, Arts and Social Sciences, Flinders University, Adelaide, SA 5001, Australia
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Abstract
SUMMARYWild-type strains ofAspergillus nidulansgrow poorly onL-histidine as a sole nitrogen source. The synthesis of the enzyme histidase (EC. 4.3.1.3) appears to be a limiting factor in the growth of the wild type, as strains carrying the mutantareA102 allele have elevated histidase levels and grow strongly on histidine as a sole nitrogen source.L-Histidine is an extremely weak sole carbon source for all strains.Ammonium repression has an important role in the regulation of histidase synthesis and the relief of ammonium repression is dependent on the availability of a good carbon source. The level of histidase synthesis does not respond to the addition of exogenous substrate.Mutants carrying lesions in thesarA orsarB loci (suppressor ofareA102) have been isolated. The growth properties of these mutants on histidine as a sole nitrogen source correlate with the levels of histidase synthesized. Mutation at thesarA andsarB loci also reduces the utilization of a number of other nitrogen sources. The data suggest that these two genes may code for regulatory products involved in nitrogen catabolism. No histidase structural gene mutants were identified and possible explanations of this are discussed.
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Polkinghorne M, Hynes MJ. Effect of L-histidine on the catabolism of nitrogenous compounds in Aspergillus nidulans. J Gen Microbiol 1975; 87:185-7. [PMID: 1094095 DOI: 10.1099/00221287-87-1-185] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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