{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T05:18:28Z","timestamp":1787980708884,"version":"build-2784847793"},"reference-count":45,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"HUN-REN-DE","award":["11003"],"award-info":[{"award-number":["11003"]}]},{"DOI":"10.13039\/501100012550","name":"Ministry of Culture and Innovation of Hungary","doi-asserted-by":"publisher","award":["149734 ADVANCED"],"award-info":[{"award-number":["149734 ADVANCED"]}],"id":[{"id":"10.13039\/501100012550","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012550","name":"Ministry of Culture and Innovation of Hungary","doi-asserted-by":"publisher","award":["2025-1.2.1-HU-RIZONT-2025-00080"],"award-info":[{"award-number":["2025-1.2.1-HU-RIZONT-2025-00080"]}],"id":[{"id":"10.13039\/501100012550","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012550","name":"Ministry of Culture and Innovation of Hungary","doi-asserted-by":"publisher","award":["2025-1.2.1-HU-RIZONT"],"award-info":[{"award-number":["2025-1.2.1-HU-RIZONT"]}],"id":[{"id":"10.13039\/501100012550","id-type":"DOI","asserted-by":"publisher"}]},{"award":["149734 ADVANCED"],"award-info":[{"award-number":["149734 ADVANCED"]}],"id":[{"id":"https:\/\/ror.org\/03vhmm238","id-type":"ROR","asserted-by":"publisher"}]},{"award":["2025-1.2.1-HU-RIZONT-2025-00080"],"award-info":[{"award-number":["2025-1.2.1-HU-RIZONT-2025-00080"]}],"id":[{"id":"https:\/\/ror.org\/03vhmm238","id-type":"ROR","asserted-by":"publisher"}]},{"award":["2025-1.2.1-HU-RIZONT"],"award-info":[{"award-number":["2025-1.2.1-HU-RIZONT"]}],"id":[{"id":"https:\/\/ror.org\/03vhmm238","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012550","name":"Ministry of Innovation and Technology of Hungary","doi-asserted-by":"publisher","award":["TKP2021-EGA-18"],"award-info":[{"award-number":["TKP2021-EGA-18"]}],"id":[{"id":"10.13039\/501100012550","id-type":"DOI","asserted-by":"publisher"}]},{"award":["TKP2021-EGA-18"],"award-info":[{"award-number":["TKP2021-EGA-18"]}],"id":[{"id":"https:\/\/ror.org\/03vhmm238","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003825","name":"Hungarian Academy of Sciences","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100003825","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/02ks8qq67","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>Background\/Objectives: Hypoxia is a major contributor to the development of retinal diseases by promoting metabolic adaptation and pathological angiogenesis through hypoxia-inducible factor (HIF) signaling. HIF-prolyl hydroxylase inhibitors (HIF-PHIs), which stabilize HIF under normoxic conditions, are widely used to treat anemia associated with chronic kidney disease. However, it remains unclear whether pharmacological HIF stabilization fully reproduces the cellular responses induced by physiological hypoxia. Methods: In this study, ARPE-19 cells were exposed to either physiological hypoxia or HIF-PHI treatment and analyzed using RNA sequencing, pathway enrichment, and pharmacological inhibition of PI3K\/Akt, mTOR, and HIF-related signaling pathways. Results: Both treatments elicited a common transcriptional response marked by the induction of glycolytic and hypoxia-responsive genes together with increased vascular endothelial growth factor a VEGFA expression. Despite these similarities, only a small number of genes differed between the two conditions, suggesting that physiological hypoxia activates additional regulatory mechanisms beyond HIF stabilization alone. Rapamycin inhibited VEGFA production only under physiological hypoxia, further supporting mechanistic differences between the two models. Functionally, conditioned media from hypoxic ARPE-19 cells promoted endothelial tube formation, which was significantly reduced by pathway inhibition. Conclusions: Collectively, these findings show that HIF-PHIs reproduce many, but not all, aspects of the physiological hypoxic response in RPE cells.<\/jats:p>","DOI":"10.3390\/ph19091355","type":"journal-article","created":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T08:02:27Z","timestamp":1787817747000},"page":"1355","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Physiological Hypoxia and Pharmacological HIF Stabilization Induce Distinct but Overlapping Responses in Retinal Pigment Epithelial Cells"],"prefix":"10.3390","volume":"19","author":[{"given":"Tam\u00e1s","family":"G\u00e1ll","sequence":"first","affiliation":[{"name":"Division of Nephrology, Department of Internal Medicine, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7549-5691","authenticated-orcid":false,"given":"D\u00e1vid","family":"Peth\u0151","sequence":"additional","affiliation":[{"name":"Division of Nephrology, Department of Internal Medicine, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary"},{"name":"HUN-REN\u2013UD Vascular Biology and Myocardium Pathophysiology Research Group, Hungarian Academy of Sciences, University of Debrecen, H-4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9722-251X","authenticated-orcid":false,"given":"Szil\u00e1rd","family":"P\u00f3liska","sequence":"additional","affiliation":[{"name":"Genomic Medicine and Bioinformatic Core Facility, Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7923-2645","authenticated-orcid":false,"given":"J\u00f3zsef","family":"Balla","sequence":"additional","affiliation":[{"name":"Division of Nephrology, Department of Internal Medicine, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary"},{"name":"HUN-REN\u2013UD Vascular Biology and Myocardium Pathophysiology Research Group, Hungarian Academy of Sciences, University of Debrecen, H-4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gy\u00f6rgy","family":"Balla","sequence":"additional","affiliation":[{"name":"HUN-REN\u2013UD Vascular Biology and Myocardium Pathophysiology Research Group, Hungarian Academy of Sciences, University of Debrecen, H-4032 Debrecen, Hungary"},{"name":"Department of Pediatrics, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Guerra, M.H., Yumnamcha, T., Ebrahim, A.S., Berger, E.A., Singh, L.P., and Ibrahim, A.S. (2021). Real-Time Monitoring the Effect of Cytopathic Hypoxia on Retinal Pigment Epithelial Barrier Functionality Using Electric Cell-Substrate Impedance Sensing (ECIS) Biosensor Technology. Int. J. Mol. Sci., 22.","DOI":"10.3390\/ijms22094568"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"631","DOI":"10.1006\/bbrc.1993.1671","article-title":"Synthesis and secretion of vascular permeability factor\/vascular endothelial growth factor by human retinal pigment epithelial cells","volume":"193","author":"Adamis","year":"1993","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"126","DOI":"10.1016\/j.cyto.2017.02.013","article-title":"Retinal pigment epithelium-secretome: A diabetic retinopathy perspective","volume":"95","author":"Ponnalagu","year":"2017","journal-title":"Cytokine"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1043","DOI":"10.1111\/ceo.13834","article-title":"Retinal pigment epithelium and age-related macular degeneration: A review of major disease mechanisms","volume":"48","author":"Somasundaran","year":"2020","journal-title":"Clin. Exp. Ophthalmol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"7324","DOI":"10.1038\/s41467-024-51624-y","article-title":"Multi-omics profiling of retinal pigment epithelium reveals enhancer-driven activation of RANK-NFATc1 signaling in traumatic proliferative vitreoretinopathy","volume":"15","author":"Liao","year":"2024","journal-title":"Nat. Commun."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"101390","DOI":"10.1016\/j.preteyeres.2025.101390","article-title":"The versatile roles of retinal pigment epithelium in the pathophysiology of retinitis pigmentosa","volume":"108","author":"Ghanawi","year":"2025","journal-title":"Prog. Retin. Eye Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1710","DOI":"10.1016\/j.fmre.2023.08.011","article-title":"The retinal pigment epithelium: Functions and roles in ocular diseases","volume":"4","author":"Wang","year":"2024","journal-title":"Fundam. Res."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1016\/j.brainres.2017.07.025","article-title":"Retinal metabolism: A comparative look at energetics in the retina","volume":"1672","author":"Country","year":"2017","journal-title":"Brain Res."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1016\/j.preteyeres.2011.11.003","article-title":"From oxygen to erythropoietin: Relevance of hypoxia for retinal development, health and disease","volume":"31","author":"Caprara","year":"2012","journal-title":"Prog. Retin. Eye Res."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1159\/000331418","article-title":"Oxygen sensing in retinal health and disease","volume":"227","author":"Lange","year":"2012","journal-title":"Ophthalmologica"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"662","DOI":"10.1038\/s41419-022-05121-z","article-title":"Hypoxia aggravates ferroptosis in RPE cells by promoting the Fenton reaction","volume":"13","author":"Henning","year":"2022","journal-title":"Cell Death Dis."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Casciano, F., Zauli, E., Rimondi, E., Mura, M., Previati, M., Busin, M., and Zauli, G. (2022). The role of the mTOR pathway in diabetic retinopathy. Front. Med., 9.","DOI":"10.3389\/fmed.2022.973856"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Audero, M.M., Prevarskaya, N., and Fiorio Pla, A. (2022). Ca2+ Signalling and Hypoxia\/Acidic Tumour Microenvironment Interplay in Tumour Progression. Int. J. Mol. Sci., 23.","DOI":"10.20944\/preprints202206.0034.v1"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"103316","DOI":"10.1016\/j.redox.2024.103316","article-title":"Heme: A link between hemorrhage and retinopathy of prematurity progression","volume":"76","author":"Egri","year":"2024","journal-title":"Redox Biol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"815","DOI":"10.1053\/j.ajkd.2016.12.011","article-title":"Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitors: A Potential New Treatment for Anemia in Patients with CKD","volume":"69","author":"Gupta","year":"2017","journal-title":"Am. J. Kidney Dis."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"19898","DOI":"10.1073\/pnas.0805817105","article-title":"Prolyl hydroxylase inhibition during hyperoxia prevents oxygen-induced retinopathy","volume":"105","author":"Sears","year":"2008","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"20541","DOI":"10.1038\/s41598-023-47942-8","article-title":"Long-term HIF-1\u03b1 stabilization reduces respiration, promotes mitophagy, and results in retinal cell death","volume":"13","author":"Nsiah","year":"2023","journal-title":"Sci. Rep."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1038\/s41392-022-01080-1","article-title":"Hypoxia signaling in human health and diseases: Implications and prospects for therapeutics","volume":"7","author":"Luo","year":"2022","journal-title":"Signal Transduct. Target. Ther."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Bin, B.H., Bhin, J., Yang, S.H., Shin, M., Nam, Y.J., Choi, D.H., Shin, D.W., Lee, A.Y., Hwang, D., and Cho, E.G. (2015). Membrane-Associated Transporter Protein (MATP) Regulates Melanosomal pH and Influences Tyrosinase Activity. PLoS ONE, 10.","DOI":"10.1371\/journal.pone.0129273"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"107707","DOI":"10.1016\/j.pharmthera.2020.107707","article-title":"Melanosome transport and regulation in development and disease","volume":"219","author":"Tian","year":"2021","journal-title":"Pharmacol. Ther."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2475","DOI":"10.1002\/jps.21991","article-title":"Involvement of LAT1 and LAT2 in the high- and low-affinity transport of L-leucine in human retinal pigment epithelial cells (ARPE-19 cells)","volume":"99","author":"Yamamoto","year":"2010","journal-title":"J. Pharm. Sci."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"5023","DOI":"10.1167\/iovs.03-0403","article-title":"Prevention of ornithine cytotoxicity by nonpolar side chain amino acids in retinal pigment epithelial cells","volume":"44","author":"Nakauchi","year":"2003","journal-title":"Investig. Ophthalmol. Vis. Sci."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Kaarniranta, K., Kajdanek, J., Morawiec, J., Pawlowska, E., and Blasiak, J. (2018). PGC-1\u03b1 Protects RPE Cells of the Aging Retina against Oxidative Stress-Induced Degeneration through the Regulation of Senescence and Mitochondrial Quality Control. The Significance for AMD Pathogenesis. Int. J. Mol. Sci., 19.","DOI":"10.3390\/ijms19082317"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"e14319","DOI":"10.7554\/eLife.14319","article-title":"Hypoxia-induced metabolic stress in retinal pigment epithelial cells is sufficient to induce photoreceptor degeneration","volume":"5","author":"Kurihara","year":"2016","journal-title":"eLife"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1172\/JCI44303","article-title":"mTOR-mediated dedifferentiation of the retinal pigment epithelium initiates photoreceptor degeneration in mice","volume":"121","author":"Zhao","year":"2011","journal-title":"J. Clin. Investig."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1016\/j.exer.2019.04.019","article-title":"Decreased lysyl oxidase level protects against development of retinal vascular lesions in diabetic retinopathy","volume":"184","author":"Kim","year":"2019","journal-title":"Exp. Eye Res."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1737","DOI":"10.1007\/s00109-020-01994-9","article-title":"Pyruvate dehydrogenase kinase\/lactate axis: A therapeutic target for neovascular age-related macular degeneration identified by metabolomics","volume":"98","author":"Lambert","year":"2020","journal-title":"J. Mol. Med."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"107997","DOI":"10.1016\/j.exer.2020.107997","article-title":"A pyruvate dehydrogenase kinase inhibitor prevents retinal cell death and improves energy metabolism in rat retinas after ischemia\/reperfusion injury","volume":"193","author":"Sato","year":"2020","journal-title":"Exp. Eye Res."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1007\/978-3-031-76550-6_56","article-title":"Desmosome and Hemidesmosome Disassembly in Retinal Pigmented Epithelium: Intersection with the Exosome Pathway","volume":"1468","author":"Klingeborn","year":"2025","journal-title":"Adv. Exp. Med. Biol."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Batie, M., Del Peso, L., and Rocha, S. (2018). Hypoxia and Chromatin: A Focus on Transcriptional Repression Mechanisms. Biomedicines, 6.","DOI":"10.20944\/preprints201803.0004.v1"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1016\/j.cell.2013.03.004","article-title":"Influence of metabolism on epigenetics and disease","volume":"153","author":"Kaelin","year":"2013","journal-title":"Cell"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"e05096","DOI":"10.1016\/j.heliyon.2020.e05096","article-title":"Isthmin 2 is decreased in preeclampsia and highly expressed in choriocarcinoma","volume":"6","author":"Martinez","year":"2020","journal-title":"Heliyon"},{"key":"ref_33","first-page":"3563","article-title":"Cigarette smoke-induced EGFR activation promotes epithelial mesenchymal migration of human retinal pigment epithelial cells through regulation of the FAK-mediated Syk\/Src pathway","volume":"17","author":"Park","year":"2018","journal-title":"Mol. Med. Rep."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"997","DOI":"10.1097\/IAE.0b013e318074c290","article-title":"Iron toxicity as a potential factor in AMD","volume":"27","author":"Wong","year":"2007","journal-title":"Retina"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"883","DOI":"10.1016\/j.ajo.2009.07.007","article-title":"Intravitreous vascular endothelial growth factor and hypoxia-inducible factor 1a in patients with proliferative diabetic retinopathy","volume":"148","author":"Wang","year":"2009","journal-title":"Am. J. Ophthalmol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"352","DOI":"10.1016\/S0008-4182(05)80078-X","article-title":"Targeting angiogenesis, the underlying disorder in neovascular age-related macular degeneration","volume":"40","author":"Ng","year":"2005","journal-title":"Can. J. Ophthalmol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1024","DOI":"10.1038\/nm1095-1024","article-title":"Vascular endothelial growth factor acts as a survival factor for newly formed retinal vessels and has implications for retinopathy of prematurity","volume":"1","author":"Alon","year":"1995","journal-title":"Nat. Med."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"G\u00e1ll, T., Peth\u0151, D., Nagy, A., P\u00f3liska, S., Balla, G., and Balla, J. (2025). Prolyl Hydroxylase Inhibitor-Mediated HIF Activation Drives Transcriptional Reprogramming in Retinal Pigment Epithelium: Relevance to Chronic Kidney Disease. Cells, 14.","DOI":"10.3390\/cells14141121"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1016\/j.kisu.2020.12.002","article-title":"Hypoxia-inducible factor-prolyl hydroxylase inhibitors in the treatment of anemia of chronic kidney disease","volume":"11","author":"Haase","year":"2021","journal-title":"Kidney Int. Suppl."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Heberle, H., Meirelles, G.V., da Silva, F.R., Telles, G.P., and Minghim, R. (2015). InteractiVenn: A web-based tool for the analysis of sets through Venn diagrams. BMC Bioinform., 16.","DOI":"10.1186\/s12859-015-0611-3"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Wickham, H. (2016). Data Analysis. ggplot2: Elegant Graphics for Data Analysis, Springer International Publishing.","DOI":"10.1007\/978-3-319-24277-4_9"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"2498","DOI":"10.1101\/gr.1239303","article-title":"Cytoscape: A software environment for integrated models of biomolecular interaction networks","volume":"13","author":"Shannon","year":"2003","journal-title":"Genome Res."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1091","DOI":"10.1093\/bioinformatics\/btp101","article-title":"ClueGO: A Cytoscape plug-in to decipher functionally grouped gene ontology and pathway annotation networks","volume":"25","author":"Bindea","year":"2009","journal-title":"Bioinformatics"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"676","DOI":"10.1038\/nmeth.2019","article-title":"Fiji: An open-source platform for biological-image analysis","volume":"9","author":"Schindelin","year":"2012","journal-title":"Nat. Methods"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"11568","DOI":"10.1038\/s41598-020-67289-8","article-title":"Angiogenesis Analyzer for ImageJ\u2014A comparative morphometric analysis of \u201cEndothelial Tube Formation Assay\u201d and \u201cFibrin Bead Assay\u201d","volume":"10","author":"Carpentier","year":"2020","journal-title":"Sci. Rep."}],"container-title":["Pharmaceuticals"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8247\/19\/9\/1355\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T04:36:28Z","timestamp":1787978188000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8247\/19\/9\/1355"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,27]]},"references-count":45,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["ph19091355"],"URL":"https:\/\/doi.org\/10.3390\/ph19091355","relation":{},"ISSN":["1424-8247"],"issn-type":[{"value":"1424-8247","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,27]]}}}