Cigarette smoke causes a bioenergetic crisis in RPE cells involving the downregulation of HIF-1α under normoxia
Abstract Age-related macular degeneration (AMD) is the most common blinding disease in the elderly population. However, there are still many uncertainties regarding the pathophysiology at the molecular level. Currently, impaired energy metabolism in retinal pigment epithelium (RPE) cells is discusse...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Nature Publishing Group
2023-10-01
|
| Series: | Cell Death Discovery |
| Online Access: | https://doi.org/10.1038/s41420-023-01695-5 |
| _version_ | 1797453892411195392 |
|---|---|
| author | Yoshiyuki Henning Katrin Willbrand Safa Larafa Gesa Weißenberg Veronika Matschke Carsten Theiss Gina-Eva Görtz Johann Matschke |
| author_facet | Yoshiyuki Henning Katrin Willbrand Safa Larafa Gesa Weißenberg Veronika Matschke Carsten Theiss Gina-Eva Görtz Johann Matschke |
| author_sort | Yoshiyuki Henning |
| collection | DOAJ |
| description | Abstract Age-related macular degeneration (AMD) is the most common blinding disease in the elderly population. However, there are still many uncertainties regarding the pathophysiology at the molecular level. Currently, impaired energy metabolism in retinal pigment epithelium (RPE) cells is discussed as one major hallmark of early AMD pathophysiology. Hypoxia-inducible factors (HIFs) are important modulators of mitochondrial function. Moreover, smoking is the most important modifiable risk factor for AMD and is known to impair mitochondrial integrity. Therefore, our aim was to establish a cell-based assay that enables us to investigate how smoking affects mitochondrial function in conjunction with HIF signaling in RPE cells. For this purpose, we treated a human RPE cell line with cigarette smoke extract (CSE) under normoxia (21% O2), hypoxia (1% O2), or by co-treatment with Roxadustat, a clinically approved HIF stabilizer. CSE treatment impaired mitochondrial integrity, involving increased mitochondrial reactive oxygen species, disruption of mitochondrial membrane potential, and altered mitochondrial morphology. Treatment effects on cell metabolism were analyzed using a Seahorse Bioanalyzer. Mitochondrial respiration and ATP production were impaired in CSE-treated cells under normoxia. Surprisingly, CSE-treated RPE cells also exhibited decreased glycolytic rate under normoxia, causing a bioenergetic crisis, because two major metabolic pathways that provide ATP were impaired by CSE. Downregulation of glycolytic rate was HIF-dependent because HIF-1α, the α-subunit of HIF-1, was downregulated by CSE on the protein level, especially under normoxia. Moreover, hypoxia incubation and treatment with Roxadustat restored glycolytic flux. Taken together, our in vitro model provides interesting insights into HIF-dependent regulation of glycolysis under normoxic conditions, which will enable us to investigate signaling pathways involved in RPE metabolism in health and disease. |
| first_indexed | 2024-03-09T15:29:26Z |
| format | Article |
| id | doaj.art-90643162a8614540a79aac6a0c9017e3 |
| institution | Directory Open Access Journal |
| issn | 2058-7716 |
| language | English |
| last_indexed | 2024-03-09T15:29:26Z |
| publishDate | 2023-10-01 |
| publisher | Nature Publishing Group |
| record_format | Article |
| series | Cell Death Discovery |
| spelling | doaj.art-90643162a8614540a79aac6a0c9017e32023-11-26T12:21:29ZengNature Publishing GroupCell Death Discovery2058-77162023-10-019111110.1038/s41420-023-01695-5Cigarette smoke causes a bioenergetic crisis in RPE cells involving the downregulation of HIF-1α under normoxiaYoshiyuki Henning0Katrin Willbrand1Safa Larafa2Gesa Weißenberg3Veronika Matschke4Carsten Theiss5Gina-Eva Görtz6Johann Matschke7Institute of Physiology, University Hospital Essen, University of Duisburg-EssenInstitute of Physiology, University Hospital Essen, University of Duisburg-EssenInstitute of Cell Biology (Cancer Research), University Hospital Essen, University of Duisburg-EssenInstitute of Physiology, University Hospital Essen, University of Duisburg-EssenDepartment of Cytology, Institute of Anatomy, Ruhr University BochumDepartment of Cytology, Institute of Anatomy, Ruhr University BochumMolecular Ophthalmology, Department of Ophthalmology, University Hospital Essen, University of Duisburg-EssenInstitute of Cell Biology (Cancer Research), University Hospital Essen, University of Duisburg-EssenAbstract Age-related macular degeneration (AMD) is the most common blinding disease in the elderly population. However, there are still many uncertainties regarding the pathophysiology at the molecular level. Currently, impaired energy metabolism in retinal pigment epithelium (RPE) cells is discussed as one major hallmark of early AMD pathophysiology. Hypoxia-inducible factors (HIFs) are important modulators of mitochondrial function. Moreover, smoking is the most important modifiable risk factor for AMD and is known to impair mitochondrial integrity. Therefore, our aim was to establish a cell-based assay that enables us to investigate how smoking affects mitochondrial function in conjunction with HIF signaling in RPE cells. For this purpose, we treated a human RPE cell line with cigarette smoke extract (CSE) under normoxia (21% O2), hypoxia (1% O2), or by co-treatment with Roxadustat, a clinically approved HIF stabilizer. CSE treatment impaired mitochondrial integrity, involving increased mitochondrial reactive oxygen species, disruption of mitochondrial membrane potential, and altered mitochondrial morphology. Treatment effects on cell metabolism were analyzed using a Seahorse Bioanalyzer. Mitochondrial respiration and ATP production were impaired in CSE-treated cells under normoxia. Surprisingly, CSE-treated RPE cells also exhibited decreased glycolytic rate under normoxia, causing a bioenergetic crisis, because two major metabolic pathways that provide ATP were impaired by CSE. Downregulation of glycolytic rate was HIF-dependent because HIF-1α, the α-subunit of HIF-1, was downregulated by CSE on the protein level, especially under normoxia. Moreover, hypoxia incubation and treatment with Roxadustat restored glycolytic flux. Taken together, our in vitro model provides interesting insights into HIF-dependent regulation of glycolysis under normoxic conditions, which will enable us to investigate signaling pathways involved in RPE metabolism in health and disease.https://doi.org/10.1038/s41420-023-01695-5 |
| spellingShingle | Yoshiyuki Henning Katrin Willbrand Safa Larafa Gesa Weißenberg Veronika Matschke Carsten Theiss Gina-Eva Görtz Johann Matschke Cigarette smoke causes a bioenergetic crisis in RPE cells involving the downregulation of HIF-1α under normoxia Cell Death Discovery |
| title | Cigarette smoke causes a bioenergetic crisis in RPE cells involving the downregulation of HIF-1α under normoxia |
| title_full | Cigarette smoke causes a bioenergetic crisis in RPE cells involving the downregulation of HIF-1α under normoxia |
| title_fullStr | Cigarette smoke causes a bioenergetic crisis in RPE cells involving the downregulation of HIF-1α under normoxia |
| title_full_unstemmed | Cigarette smoke causes a bioenergetic crisis in RPE cells involving the downregulation of HIF-1α under normoxia |
| title_short | Cigarette smoke causes a bioenergetic crisis in RPE cells involving the downregulation of HIF-1α under normoxia |
| title_sort | cigarette smoke causes a bioenergetic crisis in rpe cells involving the downregulation of hif 1α under normoxia |
| url | https://doi.org/10.1038/s41420-023-01695-5 |
| work_keys_str_mv | AT yoshiyukihenning cigarettesmokecausesabioenergeticcrisisinrpecellsinvolvingthedownregulationofhif1aundernormoxia AT katrinwillbrand cigarettesmokecausesabioenergeticcrisisinrpecellsinvolvingthedownregulationofhif1aundernormoxia AT safalarafa cigarettesmokecausesabioenergeticcrisisinrpecellsinvolvingthedownregulationofhif1aundernormoxia AT gesaweißenberg cigarettesmokecausesabioenergeticcrisisinrpecellsinvolvingthedownregulationofhif1aundernormoxia AT veronikamatschke cigarettesmokecausesabioenergeticcrisisinrpecellsinvolvingthedownregulationofhif1aundernormoxia AT carstentheiss cigarettesmokecausesabioenergeticcrisisinrpecellsinvolvingthedownregulationofhif1aundernormoxia AT ginaevagortz cigarettesmokecausesabioenergeticcrisisinrpecellsinvolvingthedownregulationofhif1aundernormoxia AT johannmatschke cigarettesmokecausesabioenergeticcrisisinrpecellsinvolvingthedownregulationofhif1aundernormoxia |