Estrogen Receptor Alpha Expression in Podocytes Mediates Protection against Apoptosis In-Vitro and In-Vivo
| Autor: | Nadezda Koleganova, Friederike Mueller, Ertan Mayatepek, Markus Bettendorf, Annette Seibt, Elisabeth Halbenz, Claus Peter Schmitt, Sebastian Kummer, Petra Lehmann, Jun Oh, Stefanie Jeruschke, Lara Vanessa Wegerich, Marie-Luise Gross-Weissmann, Andrea Peters |
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| Rok vydání: | 2011 |
| Předmět: |
Anatomy and Physiology
Mouse Kidney Glomerulus Medizin lcsh:Medicine Apoptosis Puromycin Aminonucleoside p38 Mitogen-Activated Protein Kinases Mice Endocrinology Chronic Kidney Disease lcsh:Science Inner mitochondrial membrane Cells Cultured Membrane Potential Mitochondrial Mice Knockout Mitogen-Activated Protein Kinase 1 Mitogen-Activated Protein Kinase 3 Multidisciplinary Estradiol Podocytes Animal Models Flow Cytometry Immunohistochemistry Nephrology Medicine Research Article Signal Transduction medicine.medical_specialty Blotting Western Endocrine System Context (language use) Biology Model Organisms In vivo Internal medicine medicine Animals Humans Renal Physiology Endocrine Physiology lcsh:R Estrogen Receptor alpha Renal System Hormones In vitro Membrane protein Immunology lcsh:Q Estrogen receptor alpha Hormone |
| Zdroj: | PLoS ONE, Vol 6, Iss 11, p e27457 (2011) PLoS ONE |
| ISSN: | 1932-6203 |
| DOI: | 10.1371/journal.pone.0027457 |
| Popis: | Context/Objective: Epidemiological studies have demonstrated that women have a significantly better prognosis in chronic renal diseases compared to men. This suggests critical influences of gender hormones on glomerular structure and function. We examined potential direct protective effects of estradiol on podocytes. Methods: Expression of estrogen receptor alpha (ERα) was examined in podocytes in vitro and in vivo. Receptor localization was shown using Western blot of separated nuclear and cytoplasmatic protein fractions. Podocytes were treated with Puromycin aminonucleoside (PAN, apoptosis induction), estradiol, or both in combination. Apoptotic cells were detected with Hoechst nuclear staining and Annexin-FITC flow cytometry. To visualize mitochondrial membrane potential depolarization as an indicator for apoptosis, cells were stained with tetramethyl rhodamine methylester (TMRM). Estradiol-induced phosphorylation of ERK1/2 and p38 MAPK was examined by Western blot. Glomeruli of ERα knock-out mice and wild-type controls were analysed by histomorphometry and immunohistochemistry. Results: ERα was consistently expressed in human and murine podocytes. Estradiol stimulated ERα protein expression, reduced PAN-induced apoptosis in vitro by 26.5±24.6% or 56.6±5.9% (flow cytometry or Hoechst-staining, respectively; both p&0.05), and restored PAN-induced mitochondrial membrane potential depolarization. Estradiol enhanced ERK1/2 phosphorylation. In ERα knockout mice, podocyte number was reduced compared to controls (female/male: 80/86 vs. 132/135 podocytes per glomerulus, p&0.05). Podocyte volume was enhanced in ERα knockout mice (female/male: 429/371 μm ³ vs. 264/223 μm ³ in controls, p&0.05). Tgfβ1 and collagen type IV expression were increased in knockout mice, indicating glomerular damage. Conclusions: Podocytes express ERα, whose activation leads to a significant protection against experimentally induced apoptosis. Possible underlying mechanisms include stabilization of mitochondrial membrane potential and activation of MAPK signalling. Characteristic morphological changes indicating glomerulopathy in ERα knock-out mice support the in vivo relevance of the ERα for podocyte viability and function. Thus, our findings provide a novel model for the protective influence of female gender on chronic glomerular diseases. © 2011 Kummer et al. |
| Databáze: | OpenAIRE |
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