Browsing by Author "Rhodes, Christopher J."

Now showing 1 - 5 of 5
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    Allele-specific control of rodent and human lncRNA KMT2E-AS1 promotes hypoxic endothelial pathology in pulmonary hypertension
    (American Association for the Advancement of Science, 2024) Tai, Yi-Yin; Yu, Qiujun; Tang, Ying; Sun, Wei; Kelly, Neil J.; Okawa, Satoshi; Zhao, Jingsi; Schwantes-An, Tae-Hwi; Lacoux, Caroline; Torrino, Stephanie; Al Aaraj, Yassmin; El Khoury, Wadih; Negi, Vinny; Liu, Mingjun; Corey, Catherine G.; Belmonte, Frances; Vargas, Sara O.; Schwartz, Brian; Bhat, Bal; Chau, B. Nelson; Karnes, Jason H.; Satoh, Taijyu; Barndt, Robert J.; Wu, Haodi; Parikh, Victoria N.; Wang, Jianrong; Zhang, Yingze; McNamara, Dennis; Li, Gang; Speyer, Gil; Wang, Bing; Shiva, Sruti; Kaufman, Brett; Kim, Seungchan; Gomez, Delphine; Mari, Bernard; Cho, Michael H.; Boueiz, Adel; Pauciulo, Michael W.; Southgate, Laura; Trembath, Richard C.; Sitbon, Olivier; Humbert, Marc; Graf, Stefan; Morrell, Nicholas W.; Rhodes, Christopher J.; Wilkins, Martin R.; Nouraie, Mehdi; Nichols, William C.; Desai, Ankit A.; Bertero, Thomas; Chan, Stephen Y.; Medicine, School of Medicine
    Hypoxic reprogramming of vasculature relies on genetic, epigenetic, and metabolic circuitry, but the control points are unknown. In pulmonary arterial hypertension (PAH), a disease driven by hypoxia inducible factor (HIF)-dependent vascular dysfunction, HIF-2α promoted expression of neighboring genes, long noncoding RNA (lncRNA) histone lysine N-methyltransferase 2E-antisense 1 (KMT2E-AS1) and histone lysine N-methyltransferase 2E (KMT2E). KMT2E-AS1 stabilized KMT2E protein to increase epigenetic histone 3 lysine 4 trimethylation (H3K4me3), driving HIF-2α-dependent metabolic and pathogenic endothelial activity. This lncRNA axis also increased HIF-2α expression across epigenetic, transcriptional, and posttranscriptional contexts, thus promoting a positive feedback loop to further augment HIF-2α activity. We identified a genetic association between rs73184087, a single-nucleotide variant (SNV) within a KMT2E intron, and disease risk in PAH discovery and replication patient cohorts and in a global meta-analysis. This SNV displayed allele (G)-specific association with HIF-2α, engaged in long-range chromatin interactions, and induced the lncRNA-KMT2E tandem in hypoxic (G/G) cells. In vivo, KMT2E-AS1 deficiency protected against PAH in mice, as did pharmacologic inhibition of histone methylation in rats. Conversely, forced lncRNA expression promoted more severe PH. Thus, the KMT2E-AS1/KMT2E pair orchestrates across convergent multi-ome landscapes to mediate HIF-2α pathobiology and represents a key clinical target in pulmonary hypertension.
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    Biological heterogeneity in idiopathic pulmonary arterial hypertension identified through unsupervised transcriptomic profiling of whole blood
    (Springer Nature, 2021-12-07) Kariotis, Sokratis; Jammeh, Emmanuel; Swietlik, Emilia M.; Pickworth, Josephine A.; Rhodes, Christopher J.; Otero, Pablo; Wharton, John; Iremonger, James; Dunning, Mark J.; Pandya, Divya; Mascarenhas, Thomas S.; Errington, Niamh; Thompson, A. A. Roger; Romanoski, Casey E.; Rischard, Franz; Garcia, Joe G. N.; Yuan, Jason X.-J.; Schwantes An, Tae-Hwi; Desai, Ankit A.; Coghlan, Gerry; Lordan, Jim; Corris, Paul A.; Howard, Luke S.; Condliffe, Robin; Kiely, David G.; Church, Colin; Pepke-Zaba, Joanna; Toshner, Mark; Wort, Stephen; Gräf, Stefan; Morrell, Nicholas W.; Wilkins, Martin R.; Lawrie, Allan; Wang, Dennis; UK National PAH Cohort Study Consortium; Medicine, School of Medicine
    Idiopathic pulmonary arterial hypertension (IPAH) is a rare but fatal disease diagnosed by right heart catheterisation and the exclusion of other forms of pulmonary arterial hypertension, producing a heterogeneous population with varied treatment response. Here we show unsupervised machine learning identification of three major patient subgroups that account for 92% of the cohort, each with unique whole blood transcriptomic and clinical feature signatures. These subgroups are associated with poor, moderate, and good prognosis. The poor prognosis subgroup is associated with upregulation of the ALAS2 and downregulation of several immunoglobulin genes, while the good prognosis subgroup is defined by upregulation of the bone morphogenetic protein signalling regulator NOG, and the C/C variant of HLA-DPA1/DPB1 (independently associated with survival). These findings independently validated provide evidence for the existence of 3 major subgroups (endophenotypes) within the IPAH classification, could improve risk stratification and provide molecular insights into the pathogenesis of IPAH.
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    Mining the Plasma Proteome for Insights into the Molecular Pathology of Pulmonary Arterial Hypertension
    (American Thoracic Society, 2022) Harbaum, Lars; Rhodes, Christopher J.; Wharton, John; Lawrie, Allan; Karnes, Jason H.; Desai, Ankit A.; Nichols, William C.; Humbert, Marc; Montani, David; Girerd, Barbara; Sitbon, Olivier; Boehm, Mario; Novoyatleva, Tatyana; Schermuly, Ralph T.; Ghofrani, H. Ardeschir; Toshner, Mark; Kiely, David G.; Howard, Luke S.; Swietlik, Emilia M.; Gräf, Stefan; Pietzner, Maik; Morrell, Nicholas W.; Wilkins, Martin R.; U.K. National Institute for Health Research BioResource Rare Diseases Consortium; U.K. Pulmonary Arterial Hypertension Cohort Study Consortium; U.S. Pulmonary Arterial Hypertension Biobank Consortium; Medical and Molecular Genetics, School of Medicine
    Rationale: Pulmonary arterial hypertension (PAH) is characterized by structural remodeling of pulmonary arteries and arterioles. Underlying biological processes are likely reflected in a perturbation of circulating proteins. Objectives: To quantify and analyze the plasma proteome of patients with PAH using inherited genetic variation to inform on underlying molecular drivers. Methods: An aptamer-based assay was used to measure plasma proteins in 357 patients with idiopathic or heritable PAH, 103 healthy volunteers, and 23 relatives of patients with PAH. In discovery and replication subgroups, the plasma proteomes of PAH and healthy individuals were compared, and the relationship to transplantation-free survival in PAH was determined. To examine causal relationships to PAH, protein quantitative trait loci (pQTL) that influenced protein levels in the patient population were used as instruments for Mendelian randomization (MR) analysis. Measurements and Main Results: From 4,152 annotated plasma proteins, levels of 208 differed between patients with PAH and healthy subjects, and 49 predicted long-term survival. MR based on cis-pQTL located in proximity to the encoding gene for proteins that were prognostic and distinguished PAH from health estimated an adverse effect for higher levels of netrin-4 (odds ratio [OR], 1.55; 95% confidence interval [CI], 1.16–2.08) and a protective effect for higher levels of thrombospondin-2 (OR, 0.83; 95% CI, 0.74–0.94) on PAH. Both proteins tracked the development of PAH in previously healthy relatives and changes in thrombospondin-2 associated with pulmonary arterial pressure at disease onset. Conclusions: Integrated analysis of the plasma proteome and genome implicates two secreted matrix-binding proteins, netrin-4 and thrombospondin-2, in the pathobiology of PAH.
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    NHLBI-CMREF Workshop Report on Pulmonary Vascular Disease Classification: JACC State-of-the-Art Review
    (Elsevier, 2021) Oldham, William M.; Hemnes, Anna R.; Aldred, Micheala A.; Barnard, John; Brittain, Evan L.; Chan, Stephen Y.; Cheng, Feixiong; Cho, Michael H.; Desai, Ankit A.; Garcia, Joe G.N.; Geraci, Mark W.; Ghiassian, Susan D.; Hall, Kathryn T.; Horn, Evelyn M.; Jain, Mohit; Kelly, Rachel S.; Leopold, Jane A.; Lindstrom, Sara; Modena, Brian D.; Nichols, William C.; Rhodes, Christopher J.; Sun, Wei; Sweatt, Andrew J.; Vanderpool, Rebecca R.; Wilkins, Martin R.; Wilmot, Beth; Zamanian, Roham T.; Fessel, Joshua P.; Aggarwal, Neil R.; Loscalzo, Joseph; Xiao, Lei; Medicine, School of Medicine
    The National Heart, Lung, and Blood Institute and the Cardiovascular Medical Research and Education Fund held a workshop on the application of pulmonary vascular disease omics data to the understanding, prevention, and treatment of pulmonary vascular disease. Experts in pulmonary vascular disease, omics, and data analytics met to identify knowledge gaps and formulate ideas for future research priorities in pulmonary vascular disease in line with National Heart, Lung, and Blood Institute Strategic Vision goals. The group identified opportunities to develop analytic approaches to multiomic datasets, to identify molecular pathways in pulmonary vascular disease pathobiology, and to link novel phenotypes to meaningful clinical outcomes. The committee suggested support for interdisciplinary research teams to develop and validate analytic methods, a national effort to coordinate biosamples and data, a consortium of preclinical investigators to expedite target evaluation and drug development, longitudinal assessment of molecular biomarkers in clinical trials, and a task force to develop a master clinical trials protocol for pulmonary vascular disease.
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    β-cell failure in type 2 diabetes: postulated mechanisms and prospects for prevention and treatment
    (Endocrine Society, 2014-06) Halban, Philippe A.; Polonsky, Kenneth S.; Bowden, Donald W.; Hawkins, Meredith A.; Ling, Charlotte; Mather, Kieren J.; Powers, Alvin C.; Rhodes, Christopher J.; Sussel, Lori; Weir, Gordon C.; Medicine, School of Medicine
    OBJECTIVE: This article examines the foundation of β-cell failure in type 2 diabetes (T2D) and suggests areas for future research on the underlying mechanisms that may lead to improved prevention and treatment. RESEARCH DESIGN AND METHODS: A group of experts participated in a conference on 14-16 October 2013 cosponsored by the Endocrine Society and the American Diabetes Association. A writing group prepared this summary and recommendations. RESULTS: The writing group based this article on conference presentations, discussion, and debate. Topics covered include genetic predisposition, foundations of β-cell failure, natural history of β-cell failure, and impact of therapeutic interventions. CONCLUSIONS: β-Cell failure is central to the development and progression of T2D. It antedates and predicts diabetes onset and progression, is in part genetically determined, and often can be identified with accuracy even though current tests are cumbersome and not well standardized. Multiple pathways underlie decreased β-cell function and mass, some of which may be shared and may also be a consequence of processes that initially caused dysfunction. Goals for future research include to 1) impact the natural history of β-cell failure; 2) identify and characterize genetic loci for T2D; 3) target β-cell signaling, metabolic, and genetic pathways to improve function/mass; 4) develop alternative sources of β-cells for cell-based therapy; 5) focus on metabolic environment to provide indirect benefit to β-cells; 6) improve understanding of the physiology of responses to bypass surgery; and 7) identify circulating factors and neuronal circuits underlying the axis of communication between the brain and β-cells.