Glutamate dehydrogenase requirement for apoptosis induced by aristolochic acid in renal tubular epithelial cells
Autor: | Francis Johnson, Victor Romanov, Arthur P. Grollman, Radha Bonala, Terry Whyard |
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Rok vydání: | 2011 |
Předmět: |
Cancer Research
Programmed cell death Necrosis Clinical Biochemistry Aristolochic acid Pharmaceutical Science Apoptosis Cell Line Mice chemistry.chemical_compound Glutamate Dehydrogenase medicine Animals Humans Citrate synthase Glycolysis Cells Cultured Pharmacology biology Plant Extracts Glutamate dehydrogenase Biochemistry (medical) Epithelial Cells Cell Biology Molecular biology Mitochondria Glutamine Kidney Tubules chemistry biology.protein Aristolochic Acids medicine.symptom Protein Binding |
Zdroj: | Apoptosis. 16:1217-1228 |
ISSN: | 1573-675X 1360-8185 |
DOI: | 10.1007/s10495-011-0646-5 |
Popis: | Ingestion of aristolochic acids (AA) contained in herbal remedies results in a renal disease and, frequently, urothelial malignancy. The genotoxicity of AA in renal cells, including mutagenic DNA adduct formation, is well-documented. However, the mechanisms of AA-induced tubular atrophy and renal fibrosis are largely unknown. Epithelial cell death is a critical characteristic of these pathological conditions. To elucidate the mechanisms of AA-induced cytotoxicity, we explored AA-interacting proteins in tubular epithelial cells (TEC). We found that AA interacts with a mitochondrial enzyme glutamate dehydrogenase (GDH) and moderately inhibits its activity. We report that AA induces cell death in GDH-knockdown TEC preferentially via non-apoptotic means, whereas in GDH-positive cells, death was executed by both the non-apoptotic and apoptotic mechanisms. Apoptosis is an energy-reliant process and demands higher adenosine 5'-triphosphate (ATP) consumption than does the non-apoptotic cell death. We found that, after AAI treatment, the ATP depletion is more pronounced in GDH-knockdown cells. When we reduced ATP in TEC cells by inhibition of glycolysis and mitochondrial respiration, cell death mode switched from apoptosis and necrosis to necrosis only. In addition, in cells incubated at low glucose and no glutamine conditions, oxaloacetate and pyruvate reduced AAI-induced apoptosis our data suggest that AAI-GDH interactions in TEC are critical for the induction of apoptosis by direct inhibition of GDH activity. AA binding may also induce changes in GDH conformation and promote interactions with other molecules or impair signaling by GDH metabolic products, leading to apoptosis. |
Databáze: | OpenAIRE |
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