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Kaiser-Graf D, Schulz A, Mangelsen E, Rothe M, Bolbrinker J, Kreutz R. Tissue lipidomic profiling supports a mechanistic role of the prostaglandin E2 pathway for albuminuria development in glomerular hyperfiltration. FRONTIERS IN NETWORK PHYSIOLOGY 2023; 3:1271042. [PMID: 38205443 PMCID: PMC10777844 DOI: 10.3389/fnetp.2023.1271042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 11/21/2023] [Indexed: 01/12/2024]
Abstract
Background: Glomerular hyperfiltration (GH) is an important mechanism in the development of albuminuria in hypertension. The Munich Wistar Frömter (MWF) rat is a non-diabetic model of chronic kidney disease (CKD) with GH due to inherited low nephron number resulting in spontaneous albuminuria and podocyte injury. In MWF rats, we identified prostaglandin (PG) E2 (PGE2) signaling as a potential causative mechanism of albuminuria in GH. Method: For evaluation of the renal PGE2 metabolic pathway, time-course lipidomic analysis of PGE2 and its downstream metabolites 15-keto-PGE2 and 13-14-dihydro-15-keto-PGE2 was conducted in urine, plasma and kidney tissues of MWF rats and albuminuria-resistant spontaneously hypertensive rats (SHR) by liquid chromatography electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS). Results: Lipidomic analysis revealed no dysregulation of plasma PGs over the time course of albuminuria development, while glomerular levels of PGE2 and 15-keto-PGE2 were significantly elevated in MWF compared to albuminuria-resistant SHR. Overall, averaged PGE2 levels in glomeruli were up to ×150 higher than the corresponding 15-keto-PGE2 levels. Glomerular metabolic ratios of 15-hydroxyprostaglandin dehydrogenase (15-PGDH) were significantly lower, while metabolic ratios of prostaglandin reductases (PTGRs) were significantly higher in MWF rats with manifested albuminuria compared to SHR, respectively. Conclusion: Our data reveal glomerular dysregulation of the PGE2 metabolism in the development of albuminuria in GH, resulting at least partly from reduced PGE2 degradation. This study provides first insights into dynamic changes of the PGE2 pathway that support a role of glomerular PGE2 metabolism and signaling for early albuminuria manifestation in GH.
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Affiliation(s)
- Debora Kaiser-Graf
- Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Clinical Pharmacology and Toxicology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Angela Schulz
- Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Clinical Pharmacology and Toxicology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Eva Mangelsen
- Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Clinical Pharmacology and Toxicology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | | | - Juliane Bolbrinker
- Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Clinical Pharmacology and Toxicology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Reinhold Kreutz
- Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Clinical Pharmacology and Toxicology, Charité—Universitätsmedizin Berlin, Berlin, Germany
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2
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Alp A, Saruhan E, Doğan E, Genek DG, Huddam B. Time to Change Our Viewpoints to Assess Renal Risks in Patients with Solitary Kidneys beyond Traditional Approaches? J Clin Med 2023; 12:6885. [PMID: 37959350 PMCID: PMC10649944 DOI: 10.3390/jcm12216885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 10/26/2023] [Accepted: 10/31/2023] [Indexed: 11/15/2023] Open
Abstract
Solitary functioning kidney (SFK) can be defined as the absence or hypofunction of a kidney due to acquired or congenital reasons. A congenital solitary functioning kidney (cSFK) is more common than is an acquired one (aSFK) and is characterized by the anatomical absence (agenesis) or hypofunction (hypoplasia; hypodysplasia) of one kidney from birth. Among the acquired causes, the most important is nephrectomy (Nx) (due to the donor, trauma or mass resection). Patients with SFK are at risk for the development of chronic kidney disease (CKD) in the long term. This risk potential is also significantly affected by hypertension. The relationship between hypertension and subclinical chronic inflammation is a connection that has not yet been fully clarified pathogenetically, but there are many studies highlighting this association. In recent years, studies examining different fibrosis and inflammation biomarkers in terms of the evaluation and prediction of renal risks have become increasingly popular in the literature. Oxidative stress is known to play an important role in homocysteine-induced endothelial dysfunction and has been associated with hypertension. In our study, we aimed to investigate the relationship between ambulatory blood pressure monitoring (ABPM) and urinary/serum fibrosis and inflammatory markers in patients with SFK. We prospectively investigated the relationship between ABPM results and soluble urokinase plasminogen activator receptor (suPAR), procollagen type III N-terminal peptide (PIIINP), homocysteine and other variables in 85 patients with SFK and compared them between cSFK and aSFK groups. In the etiology of SFK, a congenital or acquired origin may differ in terms of the significance of biomarkers. In particular, the serum homocysteine level may be associated with different clinical outcomes in patients with cSFK and aSFK.
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Affiliation(s)
- Alper Alp
- Department of Nephrology, Faculty of Medicine, Mugla Sıtkı Koçman University, 48000 Mugla, Turkey; (D.G.G.); (B.H.)
| | - Ercan Saruhan
- Department of Medical Biochemistry, Faculty of Medicine, Mugla Sıtkı Koçman University, 48000 Mugla, Turkey;
| | - Emrah Doğan
- Department of Radiology, Faculty of Medicine, Mugla Sıtkı Koçman University, 48000 Mugla, Turkey;
| | - Dilek Gibyeli Genek
- Department of Nephrology, Faculty of Medicine, Mugla Sıtkı Koçman University, 48000 Mugla, Turkey; (D.G.G.); (B.H.)
| | - Bülent Huddam
- Department of Nephrology, Faculty of Medicine, Mugla Sıtkı Koçman University, 48000 Mugla, Turkey; (D.G.G.); (B.H.)
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3
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Srivastava T, Garola RE, Zhou J, Boinpelly VC, Priya L, Ali MF, Rezaiekhaligh MH, Heruth DP, Novak J, Alon US, Joshi T, Jiang Y, McCarthy ET, Savin VJ, Johnson ML, Sharma R, Sharma M. Prostanoid receptors in hyperfiltration-mediated glomerular injury: Novel agonists and antagonists reveal opposing roles for EP2 and EP4 receptors. FASEB J 2022; 36:e22559. [PMID: 36125047 DOI: 10.1096/fj.202200875r] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 08/23/2022] [Accepted: 09/07/2022] [Indexed: 11/11/2022]
Abstract
Increased fluid-flow shear stress (FFSS) contributes to hyperfiltration-induced podocyte and glomerular injury resulting in progression of chronic kidney disease (CKD). We reported that increased FFSS in vitro and in vivo upregulates PGE2 receptor EP2 (but not EP4 expression), COX2-PGE2 -EP2 axis, and EP2-linked Akt-GSK3β-β-catenin signaling pathway in podocytes. To understand and use the disparities between PGE2 receptors, specific agonists, and antagonists of EP2 and EP4 were used to assess phosphorylation of Akt, GSK3β and β-catenin in podocytes using Western blotting, glomerular filtration barrier function using in vitro albumin permeability (Palb ) assay, and mitigation of hyperfiltration-induced injury in unilaterally nephrectomized (UNX) mice at 1 and 6 months. Results show an increase in Palb by PGE2 , EP2 agonist (EP2AGO ) and EP4 antagonist (EP4ANT ), but not by EP2 antagonist (EP2ANT ) or EP4 agonist (EP4AGO ). Pretreatment with EP2ANT blocked the effect of PGE2 or EP2AGO on Palb . Modulation of EP2 and EP4 also induced opposite effects on phosphorylation of Akt and β-Catenin. Individual agonists or antagonists of EP2 or EP4 did not induce significant improvement in albuminuria in UNX mice. However, treatment with a combination EP2ANT + EP4AGO for 1 or 6 months caused a robust decrease in albuminuria. EP2ANT + EP4AGO combination did not impact adaptive hypertrophy or increased serum creatinine. Observed differences between expression of EP2 and EP4 on the glomerular barrier highlight these receptors as potential targets for intervention. Safe and effective mitigating effect of EP2ANT + EP4AGO presents a novel opportunity to delay the progression of hyperfiltration-associated CKD as seen in transplant donors.
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Affiliation(s)
- Tarak Srivastava
- Section of Nephrology, Children's Mercy Hospital and University of Missouri at Kansas City, Kansas City, Missouri, USA.,Midwest Veterans' Biomedical Research Foundation (MVBRF), Kansas City, Missouri, USA.,Department of Oral and Craniofacial Sciences, University of Missouri at Kansas City-School of Dentistry, Kansas City, Missouri, USA
| | - Robert E Garola
- Department of Pathology and Laboratory Medicine, Children's Mercy Hospital and University of Missouri at Kansas City, Kansas City, Missouri, USA
| | - Jianping Zhou
- Midwest Veterans' Biomedical Research Foundation (MVBRF), Kansas City, Missouri, USA.,Renal Research Laboratory, Kansas City VA Medical Center, Kansas City, Missouri, USA
| | - Varun C Boinpelly
- Midwest Veterans' Biomedical Research Foundation (MVBRF), Kansas City, Missouri, USA.,Renal Research Laboratory, Kansas City VA Medical Center, Kansas City, Missouri, USA
| | - Lakshmi Priya
- Section of Nephrology, Children's Mercy Hospital and University of Missouri at Kansas City, Kansas City, Missouri, USA
| | - Mohammed Farhan Ali
- Section of Nephrology, Children's Mercy Hospital and University of Missouri at Kansas City, Kansas City, Missouri, USA
| | - Mohammad H Rezaiekhaligh
- Section of Nephrology, Children's Mercy Hospital and University of Missouri at Kansas City, Kansas City, Missouri, USA
| | - Daniel P Heruth
- Children's Mercy Research Institute, Children's Mercy Hospital and University of Missouri at Kansas City, Kansas City, Missouri, USA
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Uri S Alon
- Section of Nephrology, Children's Mercy Hospital and University of Missouri at Kansas City, Kansas City, Missouri, USA
| | - Trupti Joshi
- Department of Health Management and Informatics, University of Missouri, Columbia, Missouri, USA.,Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, Missouri, USA.,Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA.,MU Institute for Data Science and Informatics, University of Missouri, Columbia, Missouri, USA
| | - Yuexu Jiang
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, Missouri, USA.,Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Ellen T McCarthy
- Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Virginia J Savin
- Renal Research Laboratory, Kansas City VA Medical Center, Kansas City, Missouri, USA.,Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Mark L Johnson
- Department of Oral and Craniofacial Sciences, University of Missouri at Kansas City-School of Dentistry, Kansas City, Missouri, USA
| | - Ram Sharma
- Renal Research Laboratory, Kansas City VA Medical Center, Kansas City, Missouri, USA
| | - Mukut Sharma
- Midwest Veterans' Biomedical Research Foundation (MVBRF), Kansas City, Missouri, USA.,Renal Research Laboratory, Kansas City VA Medical Center, Kansas City, Missouri, USA.,Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
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4
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Urinary epidermal growth factor in kidney disease: A systematic review. Nefrologia 2022. [DOI: 10.1016/j.nefro.2022.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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5
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Srivastava T, Heruth DP, Duncan RS, Rezaiekhaligh MH, Garola RE, Priya L, Zhou J, Boinpelly VC, Novak J, Ali MF, Joshi T, Alon US, Jiang Y, McCarthy ET, Savin VJ, Sharma R, Johnson ML, Sharma M. Transcription Factor β-Catenin Plays a Key Role in Fluid Flow Shear Stress-Mediated Glomerular Injury in Solitary Kidney. Cells 2021; 10:cells10051253. [PMID: 34069476 PMCID: PMC8159099 DOI: 10.3390/cells10051253] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/06/2021] [Accepted: 05/14/2021] [Indexed: 01/21/2023] Open
Abstract
Increased fluid flow shear stress (FFSS) in solitary kidney alters podocyte function in vivo. FFSS-treated cultured podocytes show upregulated AKT-GSK3β-β-catenin signaling. The present study was undertaken to confirm (i) the activation of β-catenin signaling in podocytes in vivo using unilaterally nephrectomized (UNX) TOPGAL mice with the β-galactosidase reporter gene for β-catenin activation, (ii) β-catenin translocation in FFSS-treated mouse podocytes, and (iii) β-catenin signaling using publicly available data from UNX mice. The UNX of TOPGAL mice resulted in glomerular hypertrophy and increased the mesangial matrix consistent with hemodynamic adaptation. Uninephrectomized TOPGAL mice showed an increased β-galactosidase expression at 4 weeks but not at 12 weeks, as assessed using immunofluorescence microscopy (p < 0.001 at 4 weeks; p = 0.16 at 12 weeks) and X-gal staining (p = 0.008 at 4 weeks; p = 0.65 at 12 weeks). Immunofluorescence microscopy showed a significant increase in phospho-β-catenin (Ser552, p = 0.005) at 4 weeks but not at 12 weeks (p = 0.935) following UNX, and the levels of phospho-β-catenin (Ser675) did not change. In vitro FFSS caused a sustained increase in the nuclear translocation of phospho-β-catenin (Ser552) but not phospho-β-catenin (Ser675) in podocytes. The bioinformatic analysis of the GEO dataset, #GSE53996, also identified β-catenin as a key upstream regulator. We conclude that transcription factor β-catenin mediates FFSS-induced podocyte (glomerular) injury in solitary kidney.
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Affiliation(s)
- Tarak Srivastava
- Section of Nephrology, Children’s Mercy Hospital and University of Missouri at Kansas City, Kansas City, MO 64108, USA; (M.H.R.); (L.P.); (M.F.A.); (U.S.A.)
- Midwest Veterans’ Biomedical Research Foundation (MVBRF), Kansas City, MO 64128, USA; (J.Z.); (V.C.B.); (M.S.)
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri at Kansas City, Kansas City, MO 64108, USA;
- Correspondence: ; Tel.: +1-816-234-3010; Fax: +1-816-302-9919
| | - Daniel P. Heruth
- Children’s Mercy Research Institute, Children’s Mercy Hospital and University of Missouri at Kansas City, Kansas City, MO 64108, USA;
| | - R. Scott Duncan
- School of Biological Sciences, University of Missouri at Kansas City, Kansas City, MO 64108, USA;
| | - Mohammad H. Rezaiekhaligh
- Section of Nephrology, Children’s Mercy Hospital and University of Missouri at Kansas City, Kansas City, MO 64108, USA; (M.H.R.); (L.P.); (M.F.A.); (U.S.A.)
| | - Robert E. Garola
- Department of Pathology and Laboratory Medicine, Children’s Mercy Hospital and University of Missouri at Kansas City, Kansas City, MO 64108, USA;
| | - Lakshmi Priya
- Section of Nephrology, Children’s Mercy Hospital and University of Missouri at Kansas City, Kansas City, MO 64108, USA; (M.H.R.); (L.P.); (M.F.A.); (U.S.A.)
| | - Jianping Zhou
- Midwest Veterans’ Biomedical Research Foundation (MVBRF), Kansas City, MO 64128, USA; (J.Z.); (V.C.B.); (M.S.)
- Kansas City VA Medical Center, Kansas City, MO 64128, USA; (V.J.S.); (R.S.)
| | - Varun C. Boinpelly
- Midwest Veterans’ Biomedical Research Foundation (MVBRF), Kansas City, MO 64128, USA; (J.Z.); (V.C.B.); (M.S.)
- Kansas City VA Medical Center, Kansas City, MO 64128, USA; (V.J.S.); (R.S.)
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35487, USA;
| | - Mohammed Farhan Ali
- Section of Nephrology, Children’s Mercy Hospital and University of Missouri at Kansas City, Kansas City, MO 64108, USA; (M.H.R.); (L.P.); (M.F.A.); (U.S.A.)
| | - Trupti Joshi
- Department of Health Management and Informatics, University of Missouri, Columbia, MO 65211, USA;
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO 65211, USA;
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- MU Data Science and Informatics Institute, University of Missouri, Columbia, MO 65211, USA
| | - Uri S. Alon
- Section of Nephrology, Children’s Mercy Hospital and University of Missouri at Kansas City, Kansas City, MO 64108, USA; (M.H.R.); (L.P.); (M.F.A.); (U.S.A.)
| | - Yuexu Jiang
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO 65211, USA;
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Ellen T. McCarthy
- Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS 66160, USA;
| | - Virginia J. Savin
- Kansas City VA Medical Center, Kansas City, MO 64128, USA; (V.J.S.); (R.S.)
| | - Ram Sharma
- Kansas City VA Medical Center, Kansas City, MO 64128, USA; (V.J.S.); (R.S.)
| | - Mark L. Johnson
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri at Kansas City, Kansas City, MO 64108, USA;
| | - Mukut Sharma
- Midwest Veterans’ Biomedical Research Foundation (MVBRF), Kansas City, MO 64128, USA; (J.Z.); (V.C.B.); (M.S.)
- Kansas City VA Medical Center, Kansas City, MO 64128, USA; (V.J.S.); (R.S.)
- Department of Internal Medicine, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS 66160, USA;
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McArdle Z, Schreuder MF, Moritz KM, Denton KM, Singh RR. Physiology and Pathophysiology of Compensatory Adaptations of a Solitary Functioning Kidney. Front Physiol 2020; 11:725. [PMID: 32670095 PMCID: PMC7332829 DOI: 10.3389/fphys.2020.00725] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 06/03/2020] [Indexed: 12/15/2022] Open
Abstract
Children born with a solitary functioning kidney (SFK) have an increased risk of hypertension and kidney disease from early in adulthood. In response to a reduction in kidney mass, the remaining kidney undergoes compensatory kidney growth. This is associated with both an increase in size of the kidney tubules and the glomeruli and an increase in single nephron glomerular filtration rate (SNGFR). The compensatory hypertrophy and increase in filtration at the level of the individual nephron results in normalization of total glomerular filtration rate (GFR). However, over time these same compensatory mechanisms may contribute to kidney injury and hypertension. Indeed, approximately 50% of children born with a SFK develop hypertension by the age of 18 and 20–40% require dialysis by the age of 30. The mechanisms that result in kidney injury are only partly understood, and early biomarkers that distinguish those at an elevated risk of kidney injury are needed. This review will outline the compensatory adaptations to a SFK, and outline how these adaptations may contribute to kidney injury and hypertension later in life. These will be based largely on the mechanisms we have identified from our studies in an ovine model of SFK, that implicate the renal nitric oxide system, the renin angiotensin system and the renal nerves to kidney disease and hypertension associated with SFK. This discussion will also evaluate current, and speculate on next generation, prognostic factors that may predict those children at a higher risk of future kidney disease and hypertension.
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Affiliation(s)
- Zoe McArdle
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - Michiel F Schreuder
- Department of Pediatric Nephrology, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, Netherlands
| | - Karen M Moritz
- Child Health Research Centre and School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Kate M Denton
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - Reetu R Singh
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, VIC, Australia
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7
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Concerted EP2 and EP4 Receptor Signaling Stimulates Autocrine Prostaglandin E 2 Activation in Human Podocytes. Cells 2020; 9:cells9051256. [PMID: 32438662 PMCID: PMC7290667 DOI: 10.3390/cells9051256] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/29/2020] [Accepted: 05/14/2020] [Indexed: 12/14/2022] Open
Abstract
Glomerular hyperfiltration is an important mechanism in the development of albuminuria. During hyperfiltration, podocytes are exposed to increased fluid flow shear stress (FFSS) in Bowman’s space. Elevated Prostaglandin E2 (PGE2) synthesis and upregulated cyclooxygenase 2 (Cox2) are associated with podocyte injury by FFSS. We aimed to elucidate a PGE2 autocrine/paracrine pathway in human podocytes (hPC). We developed a modified liquid chromatography tandem mass spectrometry (LC/ESI-MS/MS) protocol to quantify cellular PGE2, 15-keto-PGE2, and 13,14-dihydro-15-keto-PGE2 levels. hPC were treated with PGE2 with or without separate or combined blockade of prostaglandin E receptors (EP), EP2, and EP4. Furthermore, the effect of FFSS on COX2, PTGER2, and PTGER4 expression in hPC was quantified. In hPC, stimulation with PGE2 led to an EP2- and EP4-dependent increase in cyclic adenosine monophosphate (cAMP) and COX2, and induced cellular PGE2. PTGER4 was downregulated after PGE2 stimulation in hPC. In the corresponding LC/ESI-MS/MS in vivo analysis at the tissue level, increased PGE2 and 15-keto-PGE2 levels were observed in isolated glomeruli obtained from a well-established rat model with glomerular hyperfiltration, the Munich Wistar Frömter rat. COX2 and PTGER2 were upregulated by FFSS. Our data thus support an autocrine/paracrine COX2/PGE2 pathway in hPC linked to concerted EP2 and EP4 signaling.
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