Natalia Jarzebska1, Sophia Georgi2, Normund Jabs2, Silke Brilloff2, Renke Maas3, Roman N Rodionov2, Christian Zietz4, Sabrina Montresor2, Bernd Hohenstein5, Norbert Weiss6. 1. University Center for Vascular Medicine & Department of Medicine III - Section Angiology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany. 2. University Center for Vascular Medicine & Department of Medicine III - Section Angiology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany. 3. Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Erlangen, Germany. 4. Institute of Pathology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany. 5. Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany. 6. University Center for Vascular Medicine & Department of Medicine III - Section Angiology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany. Electronic address: Norbert.Weiss@uniklinikum-dresden.de.
Abstract
BACKGROUND: The metabolic syndrome is a cluster of cardiovascular risk factors and is highly predictive for development of cardiovascular diseases. An association between elevated plasma levels of the endogenous inhibitor of nitric oxide synthases asymmetric dimethylarginine (ADMA) and risk of cardiovascular diseases has been demonstrated in numerous epidemiological studies. ADMA can be catabolized by dimethylarginine dimethylaminohydrolase (DDAH) or metabolized through a much less understood alternative pathway by alanine:glyoxylate aminotransferase 2 (AGXT2) with the formation of α-keto-δ-(N,N-dimethylguanidino)valeric acid (ADGV). Previous RT-PCR and Western Blot studies suggested that Agxt2 is expressed in the mouse kidney and liver at comparable levels, while Northern Blot and in-situ RNA-hybridisation experiments demonstrated that the kidney is the main organ of Agxt2 expression in rats. Given this discrepancy, the goal of the current study was to analyse the expression of AGXT2 in human tissues. MATERIAL AND METHODS: We analyzed AGXT2 expression in human tissues from a normal tissue bank by RT-PCR and further validated the results by Western Blot. We also performed immunohistochemical staining for AGXT2 and double fluorescent staining with an anti-AGXT2 antibody and a monoclonal anti-mitochondrial antibody. RESULTS: We saw the strongest expression of AGXT2 in the kidney and liver and confirmed this results on protein level. By IHC staining we were able to show that AGXT2 is present in the convoluted tubule in the kidney and in the liver hepatocytes. The double fluorescent staining revealed mitochondrial localization of AGXT2. CONCLUSIONS: Our current data suggest that both hepatocytes and kidney tubular epithelial cells are the major sources of AGXT2 in humans. We also demonstrated the mitochondrial localization of human AGXT2 enzyme.
BACKGROUND: The metabolic syndrome is a cluster of cardiovascular risk factors and is highly predictive for development of cardiovascular diseases. An association between elevated plasma levels of the endogenous inhibitor of nitric oxide synthases asymmetric dimethylarginine (ADMA) and risk of cardiovascular diseases has been demonstrated in numerous epidemiological studies. ADMA can be catabolized by dimethylarginine dimethylaminohydrolase (DDAH) or metabolized through a much less understood alternative pathway by alanine:glyoxylate aminotransferase 2 (AGXT2) with the formation of α-keto-δ-(N,N-dimethylguanidino)valeric acid (ADGV). Previous RT-PCR and Western Blot studies suggested that Agxt2 is expressed in the mouse kidney and liver at comparable levels, while Northern Blot and in-situ RNA-hybridisation experiments demonstrated that the kidney is the main organ of Agxt2 expression in rats. Given this discrepancy, the goal of the current study was to analyse the expression of AGXT2 in human tissues. MATERIAL AND METHODS: We analyzed AGXT2 expression in human tissues from a normal tissue bank by RT-PCR and further validated the results by Western Blot. We also performed immunohistochemical staining for AGXT2 and double fluorescent staining with an anti-AGXT2 antibody and a monoclonal anti-mitochondrial antibody. RESULTS: We saw the strongest expression of AGXT2 in the kidney and liver and confirmed this results on protein level. By IHC staining we were able to show that AGXT2 is present in the convoluted tubule in the kidney and in the liver hepatocytes. The double fluorescent staining revealed mitochondrial localization of AGXT2. CONCLUSIONS: Our current data suggest that both hepatocytes and kidney tubular epithelial cells are the major sources of AGXT2 in humans. We also demonstrated the mitochondrial localization of humanAGXT2 enzyme.
Authors: Jibran A Wali; Yen Chin Koay; Jason Chami; Courtney Wood; Leo Corcilius; Richard J Payne; Roman N Rodionov; Andreas L Birkenfeld; Dorit Samocha-Bonet; Stephen J Simpson; John F O'Sullivan Journal: Am J Physiol Endocrinol Metab Date: 2020-07-14 Impact factor: 4.310
Authors: Roman N Rodionov; Natalia Jarzebska; Dmitrii Burdin; Vladimir Todorov; Jens Martens-Lobenhoffer; Anja Hofmann; Anne Kolouschek; Nada Cordasic; Johannes Jacobi; Elena Rubets; Henning Morawietz; John F O'Sullivan; Alexander G Markov; Stefan R Bornstein; Karl Hilgers; Renke Maas; Christian Pfluecke; YingJie Chen; Stefanie M Bode-Böger; Christian P M Hugo; Bernd Hohenstein; Norbert Weiss Journal: Sci Rep Date: 2022-06-07 Impact factor: 4.996
Authors: Juliane Hannemann; Julia Zummack; Jonas Hillig; Leonard Rendant-Gantzberg; Rainer Böger Journal: J Clin Med Date: 2022-02-11 Impact factor: 4.241