Tristan Martineau1, Michel Boutin1, Anne-Marie Côté2, Bruno Maranda1, Daniel G Bichet3, Christiane Auray-Blais4. 1. Division of Medical Genetics, Department of Pediatrics, Université de Sherbrooke, Centre de recherche-CHUS, 3001, 12th Avenue North, Sherbrooke, Quebec J1H 5N4, Canada. 2. Division oef Nephrology, Department of Medicine, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Centre de recherche-CHUS, 3001, 12th Avenue North, Sherbrooke, Quebec J1H 5N4, Canada. 3. Sacré-Coeur Hospital, Université de Montréal, Quebec, Canada. 4. Division of Medical Genetics, Department of Pediatrics, Université de Sherbrooke, Centre de recherche-CHUS, 3001, 12th Avenue North, Sherbrooke, Quebec J1H 5N4, Canada. Electronic address: christiane.auray-blais@usherbrooke.ca.
Abstract
BACKGROUND: Podocytes are highly differentiated visceral cells, and several related specific proteins, such as podocalyxin and podocin are potential tools for the evaluation of podocyturia. However, precise quantitation of podocyturia-related proteins is complex and often unreliable. METHOD: A reversed-phase ultra-performance liquid chromatography coupled to tandem mass spectrometry method was developed and validated to quantify podocalyxin and podocin levels in urine supernatant by using specific cleavable peptides and standards. Urine samples from women with normotensive or hypertensive pregnancies, gestational diabetes and preeclampsia, as well as treated and untreated Fabry patients, and gender-matched controls were investigated. RESULTS: The multiplex analysis shows that podocalyxin levels were higher than podocin levels in patients, the former being particularly higher in pregnant women. Women with preeclampsia had abnormal urine levels of both proteins with a higher sensitivity for podocalyxin. Slightly increased levels of podocin were also observed in Fabry males, while both proteins were increased in untreated Fabry females. Correlations were established between podocalyxin and podocin levels and clinical parameters associated with Fabry disease and preeclampsia. CONCLUSIONS: This methodology makes possible the precise, simultaneous and reliable analysis of podocalyxin and podocin levels, and offers a valuable tool for the evaluation of podocyturia.
BACKGROUND: Podocytes are highly differentiated visceral cells, and several related specific proteins, such as podocalyxin and podocin are potential tools for the evaluation of podocyturia. However, precise quantitation of podocyturia-related proteins is complex and often unreliable. METHOD: A reversed-phase ultra-performance liquid chromatography coupled to tandem mass spectrometry method was developed and validated to quantify podocalyxin and podocin levels in urine supernatant by using specific cleavable peptides and standards. Urine samples from women with normotensive or hypertensive pregnancies, gestational diabetes and preeclampsia, as well as treated and untreated Fabry patients, and gender-matched controls were investigated. RESULTS: The multiplex analysis shows that podocalyxin levels were higher than podocin levels in patients, the former being particularly higher in pregnant women. Women with preeclampsia had abnormal urine levels of both proteins with a higher sensitivity for podocalyxin. Slightly increased levels of podocin were also observed in Fabry males, while both proteins were increased in untreated Fabry females. Correlations were established between podocalyxin and podocin levels and clinical parameters associated with Fabry disease and preeclampsia. CONCLUSIONS: This methodology makes possible the precise, simultaneous and reliable analysis of podocalyxin and podocin levels, and offers a valuable tool for the evaluation of podocyturia.
Authors: Remigiusz Bąchor; Dorota Gąszczyk; Karolina Panek-Laszczyńska; Andrzej Konieczny; Wojciech Witkiewicz; Piotr Stefanowicz; Zbigniew Szewczuk Journal: Int J Mol Sci Date: 2020-05-02 Impact factor: 5.923