1
|
Albalawy WN, Youm EB, Shipman KE, Trull KJ, Baty CJ, Long KR, Rbaibi Y, Wang XP, Fagunloye OG, White KA, Jurczak MJ, Kashlan OB, Weisz OA. SGLT2-independent effects of canagliflozin on NHE3 and mitochondrial complex I activity inhibit proximal tubule fluid transport and albumin uptake. Am J Physiol Renal Physiol 2024; 326:F1041-F1053. [PMID: 38660713 DOI: 10.1152/ajprenal.00005.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 04/03/2024] [Accepted: 04/18/2024] [Indexed: 04/26/2024] Open
Abstract
Beyond glycemic control, SGLT2 inhibitors (SGLT2is) have protective effects on cardiorenal function. Renoprotection has been suggested to involve inhibition of NHE3 leading to reduced ATP-dependent tubular workload and mitochondrial oxygen consumption. NHE3 activity is also important for regulation of endosomal pH, but the effects of SGLT2i on endocytosis are unknown. We used a highly differentiated cell culture model of proximal tubule (PT) cells to determine the direct effects of SGLT2i on Na+-dependent fluid transport and endocytic uptake in this nephron segment. Strikingly, canagliflozin but not empagliflozin reduced fluid transport across cell monolayers and dramatically inhibited endocytic uptake of albumin. These effects were independent of glucose and occurred at clinically relevant concentrations of drug. Canagliflozin acutely inhibited surface NHE3 activity, consistent with a direct effect, but did not affect endosomal pH or NHE3 phosphorylation. In addition, canagliflozin rapidly and selectively inhibited mitochondrial complex I activity. Inhibition of mitochondrial complex I by metformin recapitulated the effects of canagliflozin on endocytosis and fluid transport, whereas modulation of downstream effectors AMPK and mTOR did not. Mice given a single dose of canagliflozin excreted twice as much urine over 24 h compared with empagliflozin-treated mice despite similar water intake. We conclude that canagliflozin selectively suppresses Na+-dependent fluid transport and albumin uptake in PT cells via direct inhibition of NHE3 and of mitochondrial function upstream of the AMPK/mTOR axis. These additional targets of canagliflozin contribute significantly to reduced PT Na+-dependent fluid transport in vivo.NEW & NOTEWORTHY Reduced NHE3-mediated Na+ transport has been suggested to underlie the cardiorenal protection provided by SGLT2 inhibitors. We found that canagliflozin, but not empagliflozin, reduced NHE3-dependent fluid transport and endocytic uptake in cultured proximal tubule cells. These effects were independent of SGLT2 activity and resulted from inhibition of mitochondrial complex I and NHE3. Studies in mice are consistent with greater effects of canagliflozin versus empagliflozin on fluid transport. Our data suggest that these selective effects of canagliflozin contribute to reduced Na+-dependent transport in proximal tubule cells.
Collapse
Affiliation(s)
- Wafaa N Albalawy
- Department of Human Genetics, Pitt Public Health, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Elynna B Youm
- Department of Human Genetics, Pitt Public Health, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Katherine E Shipman
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Keelan J Trull
- Department of Chemistry and Biochemistry, University of Notre Dame, South Bend, Indiana, United States
| | - Catherine J Baty
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Kimberly R Long
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Youssef Rbaibi
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Xue-Ping Wang
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Olayemi G Fagunloye
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Katharine A White
- Department of Chemistry and Biochemistry, University of Notre Dame, South Bend, Indiana, United States
| | - Michael J Jurczak
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Ossama B Kashlan
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Ora A Weisz
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| |
Collapse
|
2
|
Eymael J, van den Broek M, Miesen L, Monge VV, van den Berge BT, Mooren F, Velez VL, Dijkstra J, Hermsen M, Bándi P, Vermeulen M, de Wildt S, Willemsen B, Florquin S, Wetzels R, Steenbergen E, Kramann R, Moeller M, Schreuder MF, Wetzels JF, van der Vlag J, Jansen J, Smeets B. Human scattered tubular cells represent a heterogeneous population of glycolytic dedifferentiated proximal tubule cells. J Pathol 2023; 259:149-162. [PMID: 36373978 PMCID: PMC10107692 DOI: 10.1002/path.6029] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 09/22/2022] [Accepted: 10/31/2022] [Indexed: 11/16/2022]
Abstract
Scattered tubular cells (STCs) are a phenotypically distinct cell population in the proximal tubule that increase in number after acute kidney injury. We aimed to characterize the human STC population. Three-dimensional human tissue analysis revealed that STCs are preferentially located within inner bends of the tubule and are barely present in young kidney tissue (<2 years), and their number increases with age. Increased STC numbers were associated with acute tubular injury (kidney injury molecule 1) and interstitial fibrosis (alpha smooth muscle actin). Isolated CD13+ CD24- CD133- proximal tubule epithelial cells (PTECs) and CD13+ CD24+ and CD13+ CD133+ STCs were analyzed using RNA sequencing. Transcriptome analysis revealed an upregulation of nuclear factor κB, tumor necrosis factor alpha, and inflammatory pathways in STCs, whereas metabolism, especially the tricarboxylic acid cycle and oxidative phosphorylation, was downregulated, without showing signs of cellular senescence. Using immunostaining and a publicly available single-cell sequencing database of human kidneys, we demonstrate that STCs represent a heterogeneous population in a transient state. In conclusion, STCs are dedifferentiated PTECs showing a metabolic shift toward glycolysis, which could facilitate cellular survival after kidney injury. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Collapse
Affiliation(s)
- Jennifer Eymael
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Martijn van den Broek
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Amalia Children's Hospital, Nijmegen, The Netherlands
| | - Laura Miesen
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Valerie Villacorta Monge
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Bartholomeus T van den Berge
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Fieke Mooren
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Vicky Luna Velez
- Department of Molecular Biology, Radboud Institute for Molecular Life Science, Nijmegen, The Netherlands
| | - Jelmer Dijkstra
- Department of Molecular Biology, Radboud Institute for Molecular Life Science, Nijmegen, The Netherlands
| | - Meyke Hermsen
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Péter Bándi
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Michiel Vermeulen
- Department of Molecular Biology, Radboud Institute for Molecular Life Science, Nijmegen, The Netherlands
| | - Saskia de Wildt
- Department of Pharmacology and Toxicology, Radboud Institute for Molecular Life Science, Nijmegen, The Netherlands
| | - Brigith Willemsen
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Sandrine Florquin
- Department of Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam Institute for Infection and Immunology, Amsterdam, The Netherlands
| | - Roy Wetzels
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Eric Steenbergen
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Rafael Kramann
- Division of Nephrology and Clinical Immunology, RWTH Aachen University, Aachen, Germany.,Institute of Experimental Medicine and Systems Biology, RWTH Aachen University, Aachen, Germany.,Department of Internal Medicine, Nephrology and Transplantation, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Marcus Moeller
- Division of Nephrology and Clinical Immunology, RWTH Aachen University, Aachen, Germany
| | - Michiel F Schreuder
- Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Amalia Children's Hospital, Nijmegen, The Netherlands
| | - Jack Fm Wetzels
- Department of Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Nephrology, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Johan van der Vlag
- Department of Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jitske Jansen
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Pediatric Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Amalia Children's Hospital, Nijmegen, The Netherlands.,Institute of Experimental Medicine and Systems Biology, RWTH Aachen University, Aachen, Germany
| | - Bart Smeets
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| |
Collapse
|
3
|
Han YP, Liu LJ, Yan JL, Chen MY, Meng XF, Zhou XR, Qian LB. Autophagy and its therapeutic potential in diabetic nephropathy. Front Endocrinol (Lausanne) 2023; 14:1139444. [PMID: 37020591 PMCID: PMC10067862 DOI: 10.3389/fendo.2023.1139444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 03/07/2023] [Indexed: 04/07/2023] Open
Abstract
Diabetic nephropathy (DN), the leading cause of end-stage renal disease, is the most significant microvascular complication of diabetes and poses a severe public health concern due to a lack of effective clinical treatments. Autophagy is a lysosomal process that degrades damaged proteins and organelles to preserve cellular homeostasis. Emerging studies have shown that disorder in autophagy results in the accumulation of damaged proteins and organelles in diabetic renal cells and promotes the development of DN. Autophagy is regulated by nutrient-sensing pathways including AMPK, mTOR, and Sirt1, and several intracellular stress signaling pathways such as oxidative stress and endoplasmic reticulum stress. An abnormal nutritional status and excess cellular stresses caused by diabetes-related metabolic disorders disturb the autophagic flux, leading to cellular dysfunction and DN. Here, we summarized the role of autophagy in DN focusing on signaling pathways to modulate autophagy and therapeutic interferences of autophagy in DN.
Collapse
Affiliation(s)
- Yu-Peng Han
- School of Basic Medical Sciences & Forensic Medicine, Hangzhou Medical College, Hangzhou, China
| | - Li-Juan Liu
- School of Basic Medical Sciences & Forensic Medicine, Hangzhou Medical College, Hangzhou, China
| | - Jia-Lin Yan
- School of Basic Medical Sciences & Forensic Medicine, Hangzhou Medical College, Hangzhou, China
| | - Meng-Yuan Chen
- School of Basic Medical Sciences & Forensic Medicine, Hangzhou Medical College, Hangzhou, China
| | - Xiang-Fei Meng
- School of Basic Medical Sciences & Forensic Medicine, Hangzhou Medical College, Hangzhou, China
| | - Xin-Ru Zhou
- School of Basic Medical Sciences & Forensic Medicine, Hangzhou Medical College, Hangzhou, China
| | - Ling-Bo Qian
- School of Basic Medical Sciences & Forensic Medicine, Hangzhou Medical College, Hangzhou, China
| |
Collapse
|