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Zakrocka I, Załuska W. The influence of cyclooxygenase inhibitors on kynurenic acid production in rat kidney: a novel path for kidney protection? Pharmacol Rep 2023; 75:376-385. [PMID: 36788192 DOI: 10.1007/s43440-023-00460-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/16/2023]
Abstract
BACKGROUND Kidney diseases have become a global health problem, affecting about 15% of adults and being often under-recognized. Immunological system activation was shown to accelerate kidney damage even in inherited disorders. The kynurenine pathway is the main route of tryptophan degradation. A metabolite of kynurenine (KYN), kynurenic acid (KYNA), produced by kynurenine aminotransferases (KATs), was reported to affect fluid and electrolyte balance as a result of natriuresis induction. The accumulation of KYNA was shown in patients with impaired kidney function and its level was related to the degree of kidney damage. Cyclooxygenase (COX) inhibitors are well-known analgesics and most of them demonstrate an anti-inflammatory effect. Their main mechanism of action is prostaglandin synthesis blockade, which is also responsible for their nephrotoxic potential. Since the KYN pathway is known to remain under immunological system control, the purpose of this study was to analyze the effect of 9 COX inhibitors on KYNA production together with KATs' activity in rat kidneys in vitro. METHODS Experiments were carried out on kidney homogenates in the presence of L-KYN and the selected compound in 6 various concentrations. RESULTS Among the examined COX inhibitors only acetaminophen did not change KYNA production in rat kidneys in vitro. Additionally, acetaminophen did not affect the activity of KAT I and KAT II, whereas acetylsalicylic acid and ibuprofen inhibited only KAT II. The remaining COX inhibitors decreased the activity of both KATs in rat kidneys in vitro. CONCLUSION Our study provides novel mechanisms of COX inhibitors action in the kidney, with possible implications for the treatment of kidney diseases.
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Affiliation(s)
- Izabela Zakrocka
- Department of Nephrology, Medical University of Lublin, Jaczewskiego 8, 20-954, Lublin, Poland.
| | - Wojciech Załuska
- Department of Nephrology, Medical University of Lublin, Jaczewskiego 8, 20-954, Lublin, Poland
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2
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Mehta PM, Gimenez G, Walker RJ, Slatter TL. Reduction of lithium induced interstitial fibrosis on co-administration with amiloride. Sci Rep 2022; 12:14598. [PMID: 36028651 PMCID: PMC9418221 DOI: 10.1038/s41598-022-18825-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 08/19/2022] [Indexed: 11/09/2022] Open
Abstract
Long-term administration of lithium is associated with chronic interstitial fibrosis that is partially reduced with exposure to amiloride. We examined potential pathways of how amiloride may reduce interstitial fibrosis. Amiloride was administered to a rat model of lithium induced interstitial fibrosis over a long term (6 months), as well as for short terms of 14 and 28 days. Kidney cortical tissue was subjected to RNA sequencing and microRNA expression analysis. Gene expression changes of interest were confirmed using immunohistochemistry on kidney tissue. Pathways identified by RNA sequencing of kidney tissue were related to 'promoting inflammation' for lithium and 'reducing inflammation' for amiloride. Validation of candidate genes found amiloride reduced inflammatory components induced by lithium including NF-κB/p65Ser536 and activated pAKTSer473, and increased p53 mediated regulatory function through increased p21 in damaged tubular epithelial cells. Amiloride also reduced the amount of Notch1 positive PDGFrβ pericytes and infiltrating CD3 cells in the interstitium. Thus, amiloride attenuates a multitude of pro-inflammatory components induced by lithium. This suggests amiloride could be repurposed as a possible anti-inflammatory, anti-fibrotic agent to prevent or reduce the development of chronic interstitial fibrosis.
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Affiliation(s)
- Paulomi M Mehta
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.,Department of Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Gregory Gimenez
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Robert J Walker
- Department of Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Tania L Slatter
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.
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3
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Pharmacophore-Model-Based Drug Repurposing for the Identification of the Potential Inhibitors Targeting the Allosteric Site in Dengue Virus NS5 RNA-Dependent RNA Polymerase. Viruses 2022; 14:v14081827. [PMID: 36016449 PMCID: PMC9412353 DOI: 10.3390/v14081827] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 08/13/2022] [Accepted: 08/15/2022] [Indexed: 11/16/2022] Open
Abstract
Dengue virus (DENV) is the causative agent of DENV infection. To tackle DENV infection, the development of therapeutic molecules as direct-acting antivirals (DAAs) has been demonstrated as a truly effective approach. Among various DENV drug targets, non-structural protein 5 (NS5)-a highly conserved protein among the family Flaviviridae-carries the RNA-dependent RNA polymerase (DENVRdRp) domain at the C-terminal, and its "N-pocket" allosteric site is widely considered for anti-DENV drug development. Therefore, in this study, we developed a pharmacophore model by utilising 41 known inhibitors of the DENVRdRp domain, and performed model screening against the FDA's approved drug database for drug repurposing against DENVRdRp. Herein, drugs complying with the pharmacophore hypothesis were further processed through standard-precision (SP) and extra-precision (XP) docking scores (DSs) and binding pose refinement based on MM/GBSA binding energy (BE) calculations. This resulted in the identification of four potential potent drugs: (i) desmopressin (DS: -10.52, BE: -69.77 kcal/mol), (ii) rutin (DS: -13.43, BE: -67.06 kcal/mol), (iii) lypressin (DS: -9.84, BE: -67.65 kcal/mol), and (iv) lanreotide (DS: -8.72, BE: -64.7 kcal/mol). The selected drugs exhibited relevant interactions with the allosteric N-pocket of DENVRdRp, including priming-loop and entry-point residues (i.e., R729, R737, K800, and E802). Furthermore, 100 ns explicit-solvent molecular dynamics simulations and end-point binding free energy assessments support the considerable stability and free energy of the selected drugs in the targeted allosteric pocket of DENVRdRp. Hence, these four drugs, repurposed as potent inhibitors of the allosteric site of DENVRdRp, are recommended for further validation using experimental assays.
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4
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Pravikova PD, Ivanova LN. Analysis of Dopamine D1- and D2-Receptors Effect on Renal Osmoregulatory Function in Rats with Different Blood Vasopressin Level. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022030267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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5
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Arachidonic Acid Metabolism and Kidney Inflammation. Int J Mol Sci 2019; 20:ijms20153683. [PMID: 31357612 PMCID: PMC6695795 DOI: 10.3390/ijms20153683] [Citation(s) in RCA: 184] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 07/19/2019] [Accepted: 07/20/2019] [Indexed: 12/17/2022] Open
Abstract
As a major component of cell membrane lipids, Arachidonic acid (AA), being a major component of the cell membrane lipid content, is mainly metabolized by three kinds of enzymes: cyclooxygenase (COX), lipoxygenase (LOX), and cytochrome P450 (CYP450) enzymes. Based on these three metabolic pathways, AA could be converted into various metabolites that trigger different inflammatory responses. In the kidney, prostaglandins (PG), thromboxane (Tx), leukotrienes (LTs) and hydroxyeicosatetraenoic acids (HETEs) are the major metabolites generated from AA. An increased level of prostaglandins (PGs), TxA2 and leukotriene B4 (LTB4) results in inflammatory damage to the kidney. Moreover, the LTB4-leukotriene B4 receptor 1 (BLT1) axis participates in the acute kidney injury via mediating the recruitment of renal neutrophils. In addition, AA can regulate renal ion transport through 19-hydroxystilbenetetraenoic acid (19-HETE) and 20-HETE, both of which are produced by cytochrome P450 monooxygenase. Epoxyeicosatrienoic acids (EETs) generated by the CYP450 enzyme also plays a paramount role in the kidney damage during the inflammation process. For example, 14 and 15-EET mitigated ischemia/reperfusion-caused renal tubular epithelial cell damage. Many drug candidates that target the AA metabolism pathways are being developed to treat kidney inflammation. These observations support an extraordinary interest in a wide range of studies on drug interventions aiming to control AA metabolism and kidney inflammation.
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6
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Abstract
Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most widely used therapeutic class in clinical medicine. These are sub-divided based on their selectivity for inhibition of cyclooxygenase (COX) isoforms (COX-1 and COX-2) into: (1) non-selective (ns-NSAIDs), and (2) selective NSAIDs (s-NSAIDs) with preferential inhibition of COX-2 isozyme. The safety and pathophysiology of NSAIDs on the renal and cardiovascular systems have continued to evolve over the years following short- and long-term treatment in both preclinical models and humans. This review summarizes major learnings on cardiac and renal complications associated with pharmaceutical inhibition of COX-1 and COX-2 with focus on preclinical to clinical translatability of cardio-renal data.
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Affiliation(s)
- Zaher A Radi
- Drug Safety Research & Development, Pfizer Research, Development & Medical, Cambridge, USA
| | - K Nasir Khan
- Drug Safety Research & Development, Pfizer Research, Development & Medical, Cambridge, USA
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7
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Renal Fibrosis mRNA Classifier: Validation in Experimental Lithium-Induced Interstitial Fibrosis in the Rat Kidney. PLoS One 2016; 11:e0168240. [PMID: 28002484 PMCID: PMC5176284 DOI: 10.1371/journal.pone.0168240] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 11/28/2016] [Indexed: 12/13/2022] Open
Abstract
Accurate diagnosis of fibrosis is of paramount clinical importance. A human fibrosis classifier based on metzincins and related genes (MARGS) was described previously. In this investigation, expression changes of MARGS genes were explored and evaluated to examine whether the MARGS-based algorithm has any diagnostic value in a rat model of lithium nephropathy. Male Wistar rats (n = 12) were divided into 2 groups (n = 6). One group was given a diet containing lithium (40 mmol/kg food for 7 days, followed by 60mmol/kg food for the rest of the experimental period), while a control group (n = 6) was fed a normal diet. After six months, animals were sacrificed and the renal cortex and medulla of both kidneys removed for analysis. Gene expression changes were analysed using 24 GeneChip® Affymetrix Rat Exon 1.0 ST arrays. Statistically relevant genes (p-value<0.05, fold change>1.5, t-test) were further examined. Matrix metalloproteinase-2 (MMP2), CD44, and nephroblastoma overexpressed gene (NOV) were overexpressed in the medulla and cortex of lithium-fed rats compared to the control group. TGFβ2 was overrepresented in the cortex of lithium-fed animals 1.5-fold, and 1.3-fold in the medulla of the same animals. In Gene Set Enrichment Analysis (GSEA), both the medulla and cortex of lithium-fed animals showed an enrichment of the MARGS, TGFβ network, and extracellular matrix (ECM) gene sets, while the cortex expression signature was enriched in additional fibrosis-related-genes and the medulla was also enriched in immune response pathways. Importantly, the MARGS-based fibrosis classifier was able to classify all samples correctly. Immunohistochemistry and qPCR confirmed the up-regulation of NOV, CD44, and TGFβ2. The MARGS classifier represents a cross-organ and cross-species classifier of fibrotic conditions and may help to design a test to diagnose and to monitor fibrosis. The results also provide evidence for a common pathway in the pathogenesis of fibrosis.
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8
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Blankenstein KI, Borschewski A, Labes R, Paliege A, Boldt C, McCormick JA, Ellison DH, Bader M, Bachmann S, Mutig K. Calcineurin inhibitor cyclosporine A activates renal Na-K-Cl cotransporters via local and systemic mechanisms. Am J Physiol Renal Physiol 2016; 312:F489-F501. [PMID: 28003191 DOI: 10.1152/ajprenal.00575.2016] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 12/05/2016] [Accepted: 12/13/2016] [Indexed: 11/22/2022] Open
Abstract
Calcineurin dephosphorylates nuclear factor of activated T cells transcription factors, thereby facilitating T cell-mediated immune responses. Calcineurin inhibitors are instrumental for immunosuppression after organ transplantation but may cause side effects, including hypertension and electrolyte disorders. Kidneys were recently shown to display activation of the furosemide-sensitive Na-K-2Cl cotransporter (NKCC2) of the thick ascending limb and the thiazide-sensitive Na-Cl cotransporter (NCC) of the distal convoluted tubule upon calcineurin inhibition using cyclosporin A (CsA). An involvement of major hormones like angiotensin II or arginine vasopressin (AVP) has been proposed. To resolve this issue, the effects of CsA treatment in normal Wistar rats, AVP-deficient Brattleboro rats, and cultured renal epithelial cells endogenously expressing either NKCC2 or NCC were studied. Acute administration of CsA to Wistar rats rapidly augmented phosphorylation levels of NKCC2, NCC, and their activating kinases suggesting intraepithelial activating effects. Chronic CsA administration caused salt retention and hypertension, along with stimulation of renin and suppression of renal cyclooxygenase 2, pointing to a contribution of endocrine and paracrine mechanisms at long term. In Brattleboro rats, CsA induced activation of NCC, but not NKCC2, and parallel effects were obtained in cultured cells in the absence of AVP. Stimulation of cultured thick ascending limb cells with AVP agonist restored their responsiveness to CsA. Our results suggest that the direct epithelial action of calcineurin inhibition is sufficient for the activation of NCC, whereas its effect on NKCC2 is more complex and requires concomitant stimulation by AVP.
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Affiliation(s)
- K I Blankenstein
- Department of Anatomy, Charité University Medicine, Berlin, Germany
| | - A Borschewski
- Department of Anatomy, Charité University Medicine, Berlin, Germany
| | - R Labes
- Department of Anatomy, Charité University Medicine, Berlin, Germany
| | - A Paliege
- Department of Anatomy, Charité University Medicine, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany
| | - C Boldt
- Department of Anatomy, Charité University Medicine, Berlin, Germany
| | - J A McCormick
- Division of Nephrology and Hypertension, Oregon Health & Science University and Veterans Affairs Medical Center, Portland, Oregon; and
| | - D H Ellison
- Division of Nephrology and Hypertension, Oregon Health & Science University and Veterans Affairs Medical Center, Portland, Oregon; and
| | - M Bader
- Max Delbrueck Center for Molecular Medicine, Berlin, Germany
| | - S Bachmann
- Department of Anatomy, Charité University Medicine, Berlin, Germany
| | - K Mutig
- Department of Anatomy, Charité University Medicine, Berlin, Germany;
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9
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Molecular mechanisms in lithium-associated renal disease: a systematic review. Int Urol Nephrol 2016; 48:1843-1853. [DOI: 10.1007/s11255-016-1352-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 06/21/2016] [Indexed: 02/07/2023]
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10
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Nørregaard R, Kwon TH, Frøkiær J. Physiology and pathophysiology of cyclooxygenase-2 and prostaglandin E2 in the kidney. Kidney Res Clin Pract 2015; 34:194-200. [PMID: 26779421 PMCID: PMC4688592 DOI: 10.1016/j.krcp.2015.10.004] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 10/13/2015] [Indexed: 01/12/2023] Open
Abstract
The cyclooxygenase (COX) enzyme system is the major pathway catalyzing the conversion of arachidonic acid into prostaglandins (PGs). PGs are lipid mediators implicated in a variety of physiological and pathophysiological processes in the kidney, including renal hemodynamics, body water and sodium balance, and the inflammatory injury characteristic in multiple renal diseases. Since the beginning of 1990s, it has been confirmed that COX exists in 2 isoforms, referred to as COX-1 and COX-2. Even though the 2 enzymes are similar in size and structure, COX-1 and COX-2 are regulated by different systems and have different functional roles. This review summarizes the current data on renal expression of the 2 COX isoforms and highlights mainly the role of COX-2 and PGE2 in several physiological and pathophysiological processes in the kidney.
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Affiliation(s)
- Rikke Nørregaard
- Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Tae-Hwan Kwon
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Korea
| | - Jørgen Frøkiær
- Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark
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11
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Nørregaard R, Tao S, Nilsson L, Woodgett JR, Kakade V, Yu ASL, Howard C, Rao R. Glycogen synthase kinase 3α regulates urine concentrating mechanism in mice. Am J Physiol Renal Physiol 2015; 308:F650-60. [PMID: 25608967 DOI: 10.1152/ajprenal.00516.2014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In mammals, glycogen synthase kinase (GSK)3 comprises GSK3α and GSK3β isoforms. GSK3β has been shown to play a role in the ability of kidneys to concentrate urine by regulating vasopressin-mediated water permeability of collecting ducts, whereas the role of GSK3α has yet to be discerned. To investigate the role of GSK3α in urine concentration, we compared GSK3α knockout (GSK3αKO) mice with wild-type (WT) littermates. Under normal conditions, GSK3αKO mice had higher water intake and urine output. GSK3αKO mice also showed reduced urine osmolality and aquaporin-2 levels but higher urinary vasopressin. When water deprived, they failed to concentrate their urine to the same level as WT littermates. The addition of 1-desamino-8-d-arginine vasopressin to isolated inner medullary collecting ducts increased the cAMP response in WT mice, but this response was reduced in GSK3αKO mice, suggesting reduced responsiveness to vasopressin. Gene silencing of GSK3α in mpkCCD cells also reduced forskolin-induced aquaporin-2 expression. When treated with LiCl, an isoform nonselective inhibitor of GSK3 and known inducer of polyuria, WT mice developed significant polyuria within 6 days. However, in GSK3αKO mice, the polyuric response was markedly reduced. This study demonstrates, for the first time, that GSK3α could play a crucial role in renal urine concentration and suggest that GSK3α might be one of the initial targets of Li(+) in LiCl-induced nephrogenic diabetes insipidus.
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Affiliation(s)
- Rikke Nørregaard
- Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Shixin Tao
- The Kidney Institute, Department of Medicine, University of Kansas Medical Center, Kansas City, Kansas
| | - Line Nilsson
- Institute of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - James R Woodgett
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada; and
| | - Vijayakumar Kakade
- The Kidney Institute, Department of Medicine, University of Kansas Medical Center, Kansas City, Kansas
| | - Alan S L Yu
- The Kidney Institute, Department of Medicine, University of Kansas Medical Center, Kansas City, Kansas
| | - Christiana Howard
- The Kidney Institute, Department of Medicine, University of Kansas Medical Center, Kansas City, Kansas
| | - Reena Rao
- The Kidney Institute, Department of Medicine, University of Kansas Medical Center, Kansas City, Kansas
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12
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Yang GX, Xu YY, Fan YP, Wang J, Chen XL, Zhang YD, Wu JH. A maladaptive role for EP4 receptors in mouse mesangial cells. PLoS One 2014; 9:e104091. [PMID: 25122504 PMCID: PMC4133176 DOI: 10.1371/journal.pone.0104091] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Accepted: 07/09/2014] [Indexed: 12/22/2022] Open
Abstract
Roles of the prostaglandin E2 E-prostanoid 4 receptor (EP4) on extracellular matrix (ECM) accumulation induced by TGF-β1 in mouse glomerular mesangial cells (GMCs) remain unknown. Previously, we have identified that TGF-β1 stimulates the expression of FN and Col I in mouse GMCs. Here we asked whether stimulation of EP4 receptors would exacerbate renal fibrosis associated with enhanced glomerular ECM accumulation. We generated EP4Flox/Flox and EP4+/− mice, cultured primary WT, EP4Flox/Flox and EP4+/− GMCs, AD-EP4 transfected WT GMCs (EP4 overexpression) and AD-Cre transfected EP4Flox/Flox GMCs (EP4 deleted). We found that TGF-β1-induced cAMP and PGE2 synthesis decreased in EP4 deleted GMCs and increased in EP4 overexpressed GMCs. Elevated EP4 expression in GMCs augmented the coupling of TGF-β1 to FN, Col I expression and COX2/PGE2 signaling, while TGF-β1 induced FN, Col I expression and COX2/PGE2 signaling were down-regulated in EP4 deficiency GMCs. 8 weeks after 5/6 nephrectomy (Nx), WT and EP4+/− mice exhibited markedly increased accumulation of ECM compared with sham-operated controls. Albuminuria, blood urea nitrogen and creatinine (BUN and Cr) concentrations were significantly increased in WT mice as compared to those of EP4+/− mice. Urine osmotic pressure was dramatically decreased after 5/6 Nx surgery in WT mice as compared to EP4+/− mice. The pathological changes in kidney of EP4+/− mice was markedly alleviated compared with WT mice. Immunohistochemical analysis showed significant reductions of Col I and FN in the kidney of EP4+/− mice compared with WT mice. Collectively, this investigation established EP4 as a potent mediator of the pro-TGF-β1 activities elicited by COX2/PGE2 in mice GMCs. Our findings suggested that prostaglandin E2, acting via EP4 receptors contributed to accumulation of ECM in GMCs and promoted renal fibrosis.
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Affiliation(s)
- Guang-xia Yang
- Department of Nephrology, Affiliated Hospital of Nantong university, Nantong, Jiangsu, China
- Department of Rheumatology, Affiliated Hospital of Jiangnan University (Wuxi 4th People's Hospital), Wuxi, Jiangsu, China
| | - Yu-yin Xu
- Department of Nephrology, Affiliated Hospital of Nantong university, Nantong, Jiangsu, China
| | - Ya-ping Fan
- Department of Nephrology, Affiliated Hospital of Nantong university, Nantong, Jiangsu, China
| | - Jing Wang
- Shanghai Jiaotong University, School of Medicine, Shanghai, China
| | - Xiao-lan Chen
- Department of Nephrology, Affiliated Hospital of Nantong university, Nantong, Jiangsu, China
- * E-mail:
| | - Yi-de Zhang
- Department of Nephrology, Affiliated Hospital of Nantong university, Nantong, Jiangsu, China
| | - Jian-hua Wu
- Department of Nephrology, Affiliated Hospital of Nantong university, Nantong, Jiangsu, China
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13
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HVAS CL, NØRREGAARD R, NIELSEN TK, BARKLIN A, TØNNESEN E. Brain death increases COX-1 and COX-2 expression in the renal medulla in a pig model. Acta Anaesthesiol Scand 2014; 58:243-50. [PMID: 24320706 DOI: 10.1111/aas.12235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/05/2013] [Indexed: 12/18/2022]
Abstract
BACKGROUND Brain death is linked to a systemic inflammatory response that includes prostaglandins and cytokines among its mediators. The levels of cyclooxygenase-1 and cyclooxygenase-2 (COX-1 and COX-2) affect graft survival, but it remains unknown whether these enzymes are modified during brain death. The aims of this study were to investigate the organ expression of COX and to analyse the cytokine response in the plasma, cerebrospinal fluid (CSF), and organs in a porcine model of intracerebral haemorrhage and brain death. METHODS Twenty pigs were randomly assigned to either a brain death group or a control group. Brain death was induced by an intracerebral injection of blood, and the animals were observed over the next 8 h. Tissue samples were tested for COX-1, COX-2 messenger RNA (mRNA) expression (heart, lung, and kidney), haeme oxygenase-1 (HO-1) (kidney), interleukin-1β (IL-1β), IL-6, IL-8, IL-10, and tumour necrosis factor-α. These cytokines were also measured at eight time points in the plasma and CSF. RESULTS At the organ level, the levels of COX-1 and COX-2 mRNA expression were increased only in the renal medulla (P = 0.03 and P = 0.02, respectively). The cytokine levels in the tissue, plasma, and CSF revealed no differences between the groups. HO-1 expression decreased (P = 0.0088). CONCLUSION Brain death increases the expression of COX-1 and COX-2 mRNA in the renal medulla. The release of cytokines into the plasma and CSF did not vary between the groups.
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Affiliation(s)
- C. L. HVAS
- Department of Anaesthesiology and Intensive Care Medicine; Aarhus University Hospital; Aarhus C Denmark
- Institute of Clinical Medicine; Aarhus University Hospital; Aarhus N Denmark
| | - R. NØRREGAARD
- Institute of Clinical Medicine; Aarhus University Hospital; Aarhus N Denmark
| | - T. K. NIELSEN
- Department of Anaesthesiology and Intensive Care Medicine; Aarhus University Hospital; Aarhus C Denmark
| | - A. BARKLIN
- Department of Anaesthesiology and Intensive Care Medicine; Aarhus University Hospital; Aarhus C Denmark
| | - E. TØNNESEN
- Department of Anaesthesiology and Intensive Care Medicine; Aarhus University Hospital; Aarhus C Denmark
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14
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Kjaersgaard G, Madsen K, Marcussen N, Jensen BL. Lithium induces microcysts and polyuria in adolescent rat kidney independent of cyclooxygenase-2. Physiol Rep 2014; 2:e00202. [PMID: 24744881 PMCID: PMC3967685 DOI: 10.1002/phy2.202] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 12/21/2013] [Indexed: 11/30/2022] Open
Abstract
In patients, chronic treatment with lithium leads to renal microcysts and nephrogenic diabetes insipidus (NDI). It was hypothesized that renal cyclooxygenase‐2 (COX‐2) activity promotes microcyst formation and NDI. Kidney microcysts were induced in male adolescent rats by feeding dams with lithium (50 mmol/kg chow) from postnatal days 7–34. Lithium treatment induced somatic growth retardation, renal microcysts and dilatations in cortical collecting duct; it increased cortical cell proliferation and inactive pGSK‐3β abundance; it lowered aquaporin‐2 (AQP2) protein abundance and induced polyuria with decreased ability to concentrate the urine; and it increased COX‐2 protein level in thick ascending limb. Concomitant treatment with lithium and a specific COX‐2 inhibitor, parecoxib (5 mg/kg per day, P10–P34), did not prevent lithium‐induced microcysts and polyuria, but improved urine concentrating ability transiently after a 1‐desamino‐8‐D‐arginine vasopressin challenge. COX‐2 inhibition did not reduce cortical lithium‐induced cell proliferation and phosphorylation of glycogen synthase kinase‐3β (GSK‐3β). COX‐1 protein abundance increased in rat kidney cortex in response to lithium. COX‐1 immunoreactivity was found in microcyst epithelium in rat kidney. A human nephrectomy specimen from a patient treated for 28 years with lithium displayed multiple, COX‐1‐immunopositive, microcysts. In chronic lithium‐treated adolescent rats, COX‐2 is not colocalized with microcystic epithelium, mitotic activity, and inactive pGSK‐3β in collecting duct; a blocker of COX‐2 does not prevent cell proliferation, cyst formation, or GSK‐3β inactivation. It is concluded that COX‐2 activity is not the primary cause for microcysts and polyuria in a NaCl‐substituted rat model of lithium nephropathy. COX‐1 is a relevant candidate to affect the injured epithelium. Long‐term use of lithium is associated with development of microcysts in the kidney. In this study the role for cyclooxygenase‐2 (COX‐2)‐derived prostaglandins in cyst formation was tested in a rat model. Inhibition of COX‐2 did not resolve or prevent kidney injury. COX‐1 was associated with the cyst epithelium and is more likely to play a functional role.
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Affiliation(s)
- Gitte Kjaersgaard
- Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense, Denmark
| | - Kirsten Madsen
- Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense, Denmark ; Department of Pathology, Odense University Hospital, Odense, Denmark
| | - Niels Marcussen
- Department of Pathology, Odense University Hospital, Odense, Denmark
| | - Boye L Jensen
- Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense, Denmark
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15
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Abstract
In the mammalian kidney, prostaglandins (PGs) are important mediators of physiologic processes, including modulation of vascular tone and salt and water. PGs arise from enzymatic metabolism of free arachidonic acid (AA), which is cleaved from membrane phospholipids by phospholipase A2 activity. The cyclooxygenase (COX) enzyme system is a major pathway for metabolism of AA in the kidney. COX are the enzymes responsible for the initial conversion of AA to PGG2 and subsequently to PGH2, which serves as the precursor for subsequent metabolism by PG and thromboxane synthases. In addition to high levels of expression of the "constitutive" rate-limiting enzyme responsible for prostanoid production, COX-1, the "inducible" isoform of cyclooxygenase, COX-2, is also constitutively expressed in the kidney and is highly regulated in response to alterations in intravascular volume. PGs and thromboxane A2 exert their biological functions predominantly through activation of specific 7-transmembrane G-protein-coupled receptors. COX metabolites have been shown to exert important physiologic functions in maintenance of renal blood flow, mediation of renin release and regulation of sodium excretion. In addition to physiologic regulation of prostanoid production in the kidney, increases in prostanoid production are also seen in a variety of inflammatory renal injuries, and COX metabolites may serve as mediators of inflammatory injury in renal disease.
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Affiliation(s)
- Raymond C Harris
- George M. O'Brien Kidney and Urologic Diseases Center and Division of Nephrology, Vanderbilt University School of Medicine and Nashville Veterans Affairs Hospital, Nashville, Tennessee, USA.
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16
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Sinke AP, Kortenoeven MLA, de Groot T, Baumgarten R, Devuyst O, Wetzels JFM, Loffing J, Deen PMT. Hydrochlorothiazide attenuates lithium-induced nephrogenic diabetes insipidus independently of the sodium-chloride cotransporter. Am J Physiol Renal Physiol 2013; 306:F525-33. [PMID: 24352504 DOI: 10.1152/ajprenal.00617.2013] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Lithium is the most common cause of nephrogenic diabetes insipidus (Li-NDI). Hydrochlorothiazide (HCTZ) combined with amiloride is the mainstay treatment in Li-NDI. The paradoxical antidiuretic action of HCTZ in Li-NDI is generally attributed to increased sodium and water uptake in proximal tubules as a compensation for increased volume loss due to HCTZ inhibition of the Na-Cl cotransporter (NCC), but alternative actions for HCTZ have been suggested. Here, we investigated whether HCTZ exerted an NCC-independent effect in Li-NDI. In polarized mouse cortical collecting duct (mpkCCD) cells, HCTZ treatment attenuated the Li-induced downregulation of aquaporin-2 (AQP2) water channel abundance. In these cells, amiloride reduces cellular Li influx through the epithelial sodium channel (ENaC). HCTZ also reduced Li influx, but to a lower extent. HCTZ increased AQP2 abundance on top of that of amiloride and did not affect the ENaC-mediated transcellular voltage. MpkCCD cells did not express NCC mRNA or protein. These data indicated that in mpkCCD cells, HCTZ attenuated lithium-induced downregulation of AQP2 independently of NCC and ENaC. Treatment of Li-NDI NCC knockout mice with HCTZ revealed a significantly reduced urine volume, unchanged urine osmolality, and increased cortical AQP2 abundance compared with Li-treated NCC knockout mice. HCTZ treatment further resulted in reduced blood Li levels, creatinine clearance, and alkalinized urinary pH. Our in vitro and in vivo data indicate that part of the antidiuretic effect of HCTZ in Li-NDI is NCC independent and may involve a tubuloglomerular feedback response-mediated reduction in glomerular filtration rate due to proximal tubular carbonic anhydrase inhibition.
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Affiliation(s)
- Anne P Sinke
- 286 Dept. of Physiology, Radboud Institute for Molecular Life Sciences, Radboud Univ. Medical Center, Geert Grooteplein Zuid 26-28, 6525 GA, Nijmegen, The Netherlands.
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17
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Kortenoeven MLA, Fenton RA. Renal aquaporins and water balance disorders. Biochim Biophys Acta Gen Subj 2013; 1840:1533-49. [PMID: 24342488 DOI: 10.1016/j.bbagen.2013.12.002] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 11/26/2013] [Accepted: 12/09/2013] [Indexed: 12/17/2022]
Abstract
BACKGROUND Aquaporins (AQPs) are a family of proteins that can act as water channels. Regulation of AQPs is critical to osmoregulation and the maintenance of body water homeostasis. Eight AQPs are expressed in the kidney of which five have been shown to play a role in body water balance; AQP1, AQP2, AQP3, AQP4 and AQP7. AQP2 in particular is regulated by vasopressin. SCOPE OF REVIEW This review summarizes our current knowledge of the underlying mechanisms of various water balance disorders and their treatment strategies. MAJOR CONCLUSIONS Dysfunctions of AQPs are involved in disorders associated with disturbed water homeostasis. Hyponatremia with increased AQP levels can be caused by diseases with low effective circulating blood volume, such as congestive heart failure, or osmoregulation disorders such as the syndrome of inappropriate secretion of antidiuretic hormone. Treatment consists of fluid restriction, demeclocycline and vasopressin type-2 receptor antagonists. Decreased AQP levels can lead to diabetes insipidus (DI), characterized by polyuria and polydipsia. In central DI, vasopressin production is impaired, while in gestational DI, levels of the vasopressin-degrading enzyme vasopressinase are abnormally increased. Treatment consists of the vasopressin analogue dDAVP. Nephrogenic DI is caused by the inability of the kidney to respond to vasopressin and can be congenital, but is most commonly acquired, usually due to lithium therapy. Treatment consists of sufficient fluid supply, low-solute diet and diuretics. GENERAL SIGNIFICANCE In recent years, our understanding of the underlying mechanisms of water balance disorders has increased enormously, which has opened up several possible new treatment strategies. This article is part of a Special Issue entitled Aquaporins.
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Affiliation(s)
- Marleen L A Kortenoeven
- Department of Biomedicine, Aarhus University, Aarhus, Denmark; Center for Interactions of Proteins in Epithelial Transport (InterPrET), Aarhus University, Aarhus, Denmark.
| | - Robert A Fenton
- Department of Biomedicine, Aarhus University, Aarhus, Denmark; Center for Interactions of Proteins in Epithelial Transport (InterPrET), Aarhus University, Aarhus, Denmark.
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18
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Kishore BK, Ecelbarger CM. Lithium: a versatile tool for understanding renal physiology. Am J Physiol Renal Physiol 2013; 304:F1139-49. [PMID: 23408166 DOI: 10.1152/ajprenal.00718.2012] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
By virtue of its unique interactions with kidney cells, lithium became an important research tool in renal physiology and pathophysiology. Investigators have uncovered the intricate relationships of lithium with the vasopressin and aldosterone systems, and the membrane channels or transporters regulated by them. While doing so, their work has also led to 1) questioning the role of adenylyl cyclase activity and prostaglandins in lithium-induced suppression of aquaporin-2 gene transcription; 2) unraveling the role of purinergic signaling in lithium-induced polyuria; and 3) highlighting the importance of the epithelial sodium channel (ENaC) in lithium-induced nephrogenic diabetes insipidus (NDI). Lithium-induced remodeling of the collecting duct has the potential to shed new light on collecting duct remodeling in disease conditions, such as diabetes insipidus. The finding that lithium inhibits glycogen synthase kinase-3β (GSK3β) has opened an avenue for studies on the role of GSK3β in urinary concentration, and GSK isoforms in renal development. Finally, proteomic and metabolomic profiling of the kidney and urine in rats treated with lithium is providing insights into how the kidney adapts its metabolism in conditions such as acquired NDI and the multifactorial nature of lithium-induced NDI. This review provides state-of-the-art knowledge of lithium as a versatile tool for understanding the molecular physiology of the kidney, and a comprehensive view of how this tool is challenging some of our long-standing concepts in renal physiology, often with paradigm shifts, and presenting paradoxical situations in renal pathophysiology. In addition, this review points to future directions in research where lithium can lead the renal community.
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Affiliation(s)
- Bellamkonda K Kishore
- Nephrology Research (151M) VA SLC Health Care System, 500 Foothill Dr, Salt Lake City, UT 84148, USA.
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19
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Abstract
PURPOSE OF REVIEW Glycogen synthase kinase-3 (GSK3) is an enzyme that is gaining prominence as a critical signaling molecule in the epithelial cells of renal tubules. This review will focus on recent findings exploring the role of GSK3 in renal collecting ducts, especially its role in urine concentration involving vasopressin signaling. RECENT FINDINGS Recent studies using inhibition or tissue-specific gene deletion of GSK3 revealed the mechanism by which GSK3 regulates aquaporin 2 water channels via adenylate cyclase or the prostaglandin-E2 pathway. In other studies, postnatal treatment with lithium, an inhibitor of GSK3, increased cell proliferation and led to microcyst formation in rat kidneys. These studies suggest that loss of GSK3 activity could interfere with renal water transport at two levels. In the short term, it could disrupt vasopressin signaling in collecting duct cells and in the long term it could alter the structure of the collecting ducts, making them less responsive to the hydro-osmotic effects of vasopressin. SUMMARY Ongoing studies reveal the crucial role played by GSK3 in the regulation of vasopressin action in the renal collecting ducts and suggest a possible use of GSK3 inhibitors in disease conditions associated with disrupted vasopressin signaling.
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20
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Abstract
Prostanoids are prominent, yet complex, components in the maintenance of body water homeostasis. Recent functional and molecular studies have revealed that the local lipid mediator PGE2 is involved both in water excretion and absorption. The biologic actions of PGE2 are exerted through four different G-protein-coupled receptors; designated EP1-4, which couple to separate intracellular signaling pathways. Here, we discuss new developments in our understanding of the actions of PGE2 that have been uncovered utilizing receptor specific agonists and antagonists, EP receptor and PG synthase knockout mice, polyuric animal models, and the new understanding of the molecular regulation of collecting duct water permeability. The role of PGE2 in urinary concentration comprises a variety of mechanisms, which are not fully understood and likely depend on which receptor is activated under a particular physiologic condition. EP3 and microsomal PG synthase type 1 play a role in decreasing collecting duct water permeability and increasing water excretion, whereas EP2 and EP4 can bypass vasopressin signaling and increase water reabsorption through two different intracellular signaling pathways. PGE2 has an intricate role in urinary concentration, and we now suggest how targeting specific prostanoid receptor signaling pathways could be exploited for the treatment of disorders in water balance.
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Affiliation(s)
- Emma T B Olesen
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
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21
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Bao H, Ge Y, Zhuang S, Dworkin LD, Liu Z, Gong R. Inhibition of glycogen synthase kinase-3β prevents NSAID-induced acute kidney injury. Kidney Int 2012; 81:662-73. [PMID: 22258319 PMCID: PMC3305839 DOI: 10.1038/ki.2011.443] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Clinical use of nonsteroidal anti-inflammatory drugs (NSAIDs) like diclofenac (DCLF) is limited by multiple adverse effects, including renal toxicity leading to acute kidney injury. In mice with DCLF-induced nephrotoxicity, TDZD-8, a selective glycogen synthase kinase (GSK)3β inhibitor, improved acute kidney dysfunction and ameliorated tubular necrosis and apoptosis associated with induced cortical expression of cyclooxygenase-2 (COX-2) and prostaglandin E2. This renoprotective effect was blunted but still largely preserved in COX-2-null mice, suggesting that other GSK3β targets beyond COX-2 functioned in renal protection. Indeed, TDZD-8 diminished the mitochondrial permeability transition in DCLF-injured kidneys. In vitro, GSK3β inhibition reinstated viability and suppressed necrosis and apoptosis in DCLF-stimulated tubular epithelial cells. DCLF elicited oxidative stress, enhanced the activity of the redox-sensitive GSK3β, and promoted a mitochondrial permeability transition by interacting with cyclophilin D, a key component of the mitochondrial permeability transition pore. TDZD-8 blocked GSK3β activity and prevented GSK3β-mediated cyclophilin D phosphorylation and the ensuing mitochondrial permeability transition, concomitant with normalization of intracellular ATP. Conversely, ectopic expression of a constitutively active GSK3β abolished the effects of TDZD-8. Hence, inhibition of GSK3β ameliorates NSAID-induced acute kidney injury by induction of renal cortical COX-2 and direct inhibition of the mitochondrial permeability transition.
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Affiliation(s)
- Hao Bao
- Research Institute of Nephrology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
- Division of Kidney Disease and Hypertension, Brown University School of Medicine, Providence, Rhode Island, USA
| | - Yan Ge
- Division of Kidney Disease and Hypertension, Brown University School of Medicine, Providence, Rhode Island, USA
| | - Shougang Zhuang
- Division of Kidney Disease and Hypertension, Brown University School of Medicine, Providence, Rhode Island, USA
| | - Lance D Dworkin
- Division of Kidney Disease and Hypertension, Brown University School of Medicine, Providence, Rhode Island, USA
| | - Zhihong Liu
- Research Institute of Nephrology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | - Rujun Gong
- Division of Kidney Disease and Hypertension, Brown University School of Medicine, Providence, Rhode Island, USA
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22
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Yamamoto E, Izawa T, Kuwamura M, Yamate J. Immunohistochemical Expressions of Main PGE(2) Biosynthesis-related Enzymes and PGE(2) Receptor in Rat Nephrogenesis. J Toxicol Pathol 2011; 24:257-61. [PMID: 22319240 PMCID: PMC3266363 DOI: 10.1293/tox.24.257] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Accepted: 06/10/2011] [Indexed: 11/19/2022] Open
Abstract
Endogenous prostaglandin (PG) E(2) plays important roles in renal homeostasis. Immunoexpressions of PGE(2) biosynthesis-related enzymes, cyclooxygenase (COX)-2 and microsomal PGE(2) synthetase (mPGES)-1 and EP4 (a PGE(2) receptor), were investigated in renal development. Kidney tissues were obtained from fetuses on gestation days 18 and 21 and neonates on days 1 to 18. In fetuses and early neonates, the expressions of COX-2, mPGES-1 and EP4 were observed in developing renal tubules, indicating that COX-2 and its product, PGE(2), play important roles in blastemal cell-derived renal tubular development via EP4. Cyclin D1 expression was seen in both the nucleus and cytoplasm of the developing tubules. These findings differed from the decreased COX-2 expression and exclusive nuclear expression of cyclin D1 seen in abnormal epithelial regeneration of injured renal tubules in cisplatin-treated rats in our previous articles. Collectively, PGE(2), induced by COX-2, regulates renal tubular epithelial formation via EP4.
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Affiliation(s)
- Emi Yamamoto
- Laboratory of Veterinary Pathology, Life and Environmental
Sciences, Osaka Prefecture University, Rinkuu Ourai Kita 1-58, Izumisano, Osaka 598-8531,
Japan
| | - Takeshi Izawa
- Laboratory of Veterinary Pathology, Life and Environmental
Sciences, Osaka Prefecture University, Rinkuu Ourai Kita 1-58, Izumisano, Osaka 598-8531,
Japan
| | - Mitsuru Kuwamura
- Laboratory of Veterinary Pathology, Life and Environmental
Sciences, Osaka Prefecture University, Rinkuu Ourai Kita 1-58, Izumisano, Osaka 598-8531,
Japan
| | - Jyoji Yamate
- Laboratory of Veterinary Pathology, Life and Environmental
Sciences, Osaka Prefecture University, Rinkuu Ourai Kita 1-58, Izumisano, Osaka 598-8531,
Japan
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23
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Nahman S, Belmaker RH, Azab AN. Effects of lithium on lipopolysaccharide-induced inflammation in rat primary glia cells. Innate Immun 2011; 18:447-58. [DOI: 10.1177/1753425911421512] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Lithium is the gold-standard treatment for bipolar disorder, a severe mental illness. A large body of evidence suggests that inflammation plays a role in the pathogenesis of bipolar disorder and that mood stabilizers exhibit anti-inflammatory properties. However, contradicting findings have also been reported. In this study, we examined the effects of lithium on LPS-induced inflammation in rat primary glia cells. Cells were pre-treated with lithium (1 or 10 mM) for 6 or 24 h, after which, inflammation was induced by the addition of LPS (for another 18 h) to the culture medium. Thereafter, medium was collected and cells were harvested for further analyses. Levels of TNF-α, IL1-β and PGE2 were determined by ELISA and NO levels by the Griess reaction assay. Expression levels of cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS) were examined by Western blot analysis. We found that pre-treatment with lithium 10 mM (but not 1 mM) significantly reduced LPS-induced secretion of TNF-α, IL1-β, PGE2 and NO. In addition, lithium significantly reduced the expression of COX-2 and iNOS. These findings indicate that lithium exhibits a potent anti-inflammatory effect. However, it’s important to emphasize that this effect was obtained mainly under treatment with an extra-therapeutic concentration of the drug.
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Affiliation(s)
- Sigalit Nahman
- Department of Clinical Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-sheva, Israel
- Psychiatry Research Unit and Mental Health Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-sheva, Israel
| | - RH Belmaker
- Psychiatry Research Unit and Mental Health Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-sheva, Israel
| | - Abed N Azab
- Department of Clinical Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-sheva, Israel
- School for Community Health Professions, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-sheva, Israel
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24
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Kortenoeven MLA, Schweer H, Cox R, Wetzels JFM, Deen PMT. Lithium reduces aquaporin-2 transcription independent of prostaglandins. Am J Physiol Cell Physiol 2011; 302:C131-40. [PMID: 21881002 DOI: 10.1152/ajpcell.00197.2011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Vasopressin (AVP)-stimulated translocation and transcription of aquaporin-2 (AQP2) water channels in renal principal cells is essential for urine concentration. Twenty percent of patients treated with lithium develop nephrogenic diabetes insipidus (NDI), a disorder in which the kidney is unable to concentrate urine. In vivo and in mouse collecting duct (mpkCCD) cells, lithium treatment coincides with decreased AQP2 abundance and inactivation of glycogen synthase kinase (Gsk) 3β. This is paralleled in vivo by an increased renal cyclooxygenase 2 (COX-2) expression and urinary prostaglandin PGE(2) excretion. PGE(2) reduces AVP-stimulated water reabsorption, but its precise role in lithium-induced downregulation of AQP2 is unclear. Using mpkCCD cells, we here investigated whether prostaglandins contribute to lithium-induced downregulation of AQP2. In these cells, lithium application reduced AQP2 abundance, which coincided with Gsk3β inactivation and increased COX-2 expression. Inhibition of COX by indomethacin, leading to reduced PGE(2) and PGF(2α) levels, or dexamethasone-induced downregulation of COX-2 both increased AQP2 abundance, while PGE(2) addition reduced AQP2 abundance. However, lithium did not change the prostaglandin levels, and indomethacin and dexamethasone did not prevent lithium-induced AQP2 downregulation. Further analysis revealed that lithium decreased AQP2 protein abundance, mRNA levels and transcription, while PGE(2) reduced AQP2 abundance by increasing its lysosomal degradation, but not by reducing AQP2 gene transcription. In conclusion, our data reveal that in mpkCCD cells, prostaglandins decrease AQP2 protein stability by increasing its lysosomal degradation, indicating that in vivo paracrine-produced prostaglandins might have a role in lithium-induced NDI via this mechanism. However, lithium affects also AQP2 gene transcription, which is prostaglandin independent.
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25
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Tusgaard B, Nørregaard R, Jensen AM, Wang G, Topcu SO, Wang Y, Nielsen S, Frøkiaer J. Cisplatin decreases renal cyclooxygenase-2 expression and activity in rats. Acta Physiol (Oxf) 2011; 202:79-90. [PMID: 21272267 DOI: 10.1111/j.1748-1716.2011.02257.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
AIM Cisplatin (CP) induced acute renal failure (ARF) has previously been associated with decreased urinary prostaglandin E2 (PGE2) excretion and reduced aquaporin 2 (AQP2) expression in kidney collecting duct. In this study we examined the expression of cyclooxygenase (COX)-1 and -2 as well as AQP2 and the Na-K-2Cl cotransporter in kidneys from rats with CP induced ARF. METHODS Rats were treated with either CP or saline and followed for 5 days. Kidneys were dissected into three zones and prepared for immunoblotting, quantitative polymerase chain reaction (QPCR) and immunohistochemistry. Renal content and urinary PGE2 excretion was measured. RESULTS Cisplatin treatment was associated with polyuria and a significant decreased creatinine clearance. Inner medullary PGE2 content and urinary PGE2 excretion was decreased in CP-treated rats. QPCR and semiquatitative immunoblotting demonstrated that CP treatment reduced COX-2, AQP2 and Na-K-2Cl cotransporter abundance in the different kidney zones, whereas no change in COX-1 was observed. Results were confirmed by immunohistochemistry. CONCLUSION Cyclooxygenase-2 expression is decreased in inner medulla and cortex. Consistent with this urinary PGE2 levels were reduced. These data suggest that downregulation of COX-2 is responsible for impaired de novo generation of vasodilatory prostaglandins which may play an important role for the CP induced renal vasoconstriction and development of nephropathy.
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Affiliation(s)
- B Tusgaard
- The Water and Salt Research Center, University of Aarhus, Denmark
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26
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Yamamoto E, Izawa T, Juniantito V, Kuwamura M, Yamate J. Relationship of Cell Proliferating Marker Expressions with PGE(2) Receptors in Regenerating Rat Renal Tubules after Cisplatin Injection. J Toxicol Pathol 2010; 23:271-5. [PMID: 22272038 PMCID: PMC3234632 DOI: 10.1293/tox.23.271] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Accepted: 07/05/2010] [Indexed: 11/20/2022] Open
Abstract
Cisplatin, an anticancer drug, is well known to have nephrotoxicity as an adverse effect. We investigated the expressions of cell cycle markers and prostaglandin E(2) (PGE(2)) receptors (EP) in the affected renal tubules in rats injected with a single dose (6 mg/kg body weight) of cisplatin. On days 1-3 after dosing, the affected renal epithelial cells were almost desquamated, showing necrosis. On day 5 onwards, the renal tubules were rimmed by flattened or cuboidal epithelial cells with basophilic cytoplasm; BrdU-immunopositive cells began to significantly increase, indicating regeneration. Simultaneously, TUNEL-positive apoptotic cells were also seen. On days 1-5, cyclin D1-immunopositive cells were decreased with an increased expression in p21 mRNA, indicating G(1) arrest in the cell cycle. The affected renal epithelial cells began to react to EP4 receptor, but not to EP2 receptor. Some EP4 receptor-reacting epithelial cells gave a positive reaction to BrdU or cyclin D1. Collectively, the affected renal tubules underwent various alterations such as necrosis, apoptosis, regeneration and G(1) arrest; the aspects might be influenced by endogenous PGE(2) through EP4 receptor.
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Affiliation(s)
- Emi Yamamoto
- Laboratory of Veterinary Pathology, Life and Environmental Sciences,
Osaka Prefecture University, 1–58 Rinku Ourai-Kita, Izumisano, Osaka 598-8531,
Japan
| | - Takeshi Izawa
- Laboratory of Veterinary Pathology, Life and Environmental Sciences,
Osaka Prefecture University, 1–58 Rinku Ourai-Kita, Izumisano, Osaka 598-8531,
Japan
| | - Vetnizah Juniantito
- Laboratory of Veterinary Pathology, Life and Environmental Sciences,
Osaka Prefecture University, 1–58 Rinku Ourai-Kita, Izumisano, Osaka 598-8531,
Japan
| | - Mitsuru Kuwamura
- Laboratory of Veterinary Pathology, Life and Environmental Sciences,
Osaka Prefecture University, 1–58 Rinku Ourai-Kita, Izumisano, Osaka 598-8531,
Japan
| | - Jyoji Yamate
- Laboratory of Veterinary Pathology, Life and Environmental Sciences,
Osaka Prefecture University, 1–58 Rinku Ourai-Kita, Izumisano, Osaka 598-8531,
Japan
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27
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Rao R, Patel S, Hao C, Woodgett J, Harris R. GSK3beta mediates renal response to vasopressin by modulating adenylate cyclase activity. J Am Soc Nephrol 2010; 21:428-37. [PMID: 20056751 DOI: 10.1681/asn.2009060672] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Glycogen synthase kinase 3beta (GSK3beta), a serine/threonine protein kinase, is a key target of drug discovery in several diseases, including diabetes and Alzheimer disease. Because lithium, a potent inhibitor of GSK3beta, causes nephrogenic diabetes insipidus, GSK3beta may play a crucial role in regulating water homeostasis. We developed renal collecting duct-specific GSK3beta knockout mice to determine whether deletion of GSK3beta affects arginine vasopressin-dependent renal water reabsorption. Although only mildly polyuric under normal conditions, knockout mice exhibited an impaired urinary concentrating ability in response to water deprivation or treatment with a vasopressin analogue. The knockout mice had reduced levels of mRNA, protein, and membrane localization of the vasopressin-responsive water channel aquaporin 2 compared with wild-type mice. The knockout mice also expressed lower levels of pS256-AQP2, a phosphorylated form crucial for membrane trafficking. Levels of cAMP, a major regulator of aquaporin 2 expression and trafficking, were also lower in the knockout mice. Both GSK3beta gene deletion and pharmacologic inhibition of GSK3beta reduced adenylate cyclase activity. In summary, GSK3beta inactivation or deletion reduces aquaporin 2 expression by modulating adenylate cyclase activity and cAMP generation, thereby impairing responses to vasopressin in the renal collecting duct.
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Affiliation(s)
- Reena Rao
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA.
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28
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Jia Z, Wang H, Yang T. Mice lacking mPGES-1 are resistant to lithium-induced polyuria. Am J Physiol Renal Physiol 2009; 297:F1689-96. [PMID: 19692487 DOI: 10.1152/ajprenal.00117.2009] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cyclooxygenase-2 activity is required for the development of lithium-induced polyuria. However, the involvement of a specific, terminal prostaglandin (PG) isomerase has not been evaluated. The present study was undertaken to assess lithium-induced polyuria in mice deficient in microsomal prostaglandin E synthase-1 (mPGES-1). A 2-wk administration of LiCl (4 mmol.kg(-1).day(-1) ip) in mPGES-1 +/+ mice led to a marked polyuria with hyposmotic urine. This was associated with elevated renal mPGES-1 protein expression and increased urine PGE(2) excretion. In contrast, mPGES-1 -/- mice were largely resistant to lithium-induced polyuria and a urine concentrating defect, accompanied by nearly complete blockade of high urine PGE(2) and cAMP output. Immunoblotting, immunohistochemistry, and quantitative (q) RT-PCR consistently detected a significant decrease in aquaporin-2 (AQP2) protein expression in both the renal cortex and medulla of lithium-treated +/+ mice. This decrease was significantly attenuated in the -/- mice. qRT-PCR detected similar patterns of changes in AQP2 mRNA in the medulla but not in the cortex. Similarly, the total protein abundance of the Na-K-2Cl cotransporter (NKCC2) in the medulla but not in the cortex of the +/+ mice was significantly reduced by lithium treatment. In contrast, the dowregulation of renal medullary NKCC2 expression was significantly attenuated in the -/- mice. We conclude that mPGES-1-derived PGE(2) mediates lithium-induced polyuria likely via inhibition of AQP2 and NKCC2 expression.
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Affiliation(s)
- Zhanjun Jia
- Univ. of Utah and VA Medical Center, Salt Lake City, UT 84132, USA
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29
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Grandjean EM, Aubry JM. Lithium: updated human knowledge using an evidence-based approach: part III: clinical safety. CNS Drugs 2009; 23:397-418. [PMID: 19453201 DOI: 10.2165/00023210-200923050-00004] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Lithium use in mental diseases has changed over the years but remains a cornerstone of treatment in bipolar disorders. In two companion papers, we have reviewed existing (and especially recent) data on lithium efficacy and updated basic knowledge regarding the practical fundamentals of lithium therapy. The present paper reviews safety data on lithium available to date. Gastrointestinal pain or discomfort, diarrhoea, tremor, polyuria, nocturnal urination, weight gain, oedema, flattening of affect and exacerbation of psoriasis are typical complaints of patients receiving long-term lithium therapy. Renal involvement results in a reduced urinary concentrating capacity, expressed as obligate polyuria, with secondary thirst. With long-term therapy, this may result in nephrogenic diabetes insipidus. In addition, glomerular filtration rate falls slightly in about 20% of patients. The view that only a few patients receiving long-term lithium are at increased risk of glomerular impairment and progressive renal insufficiency should be regarded with caution. The risk is increased in case of concomitant diseases or medications. Lithium treatment may inhibit thyroid hormone release and induce goitre. Consequently, the prevalence of both overt and subclinical hypothyroidism is increased, with circulating thyroid auto-antibodies frequently being found. Much less commonly, thyrotoxicosis may also develop in association with lithium therapy. Long-term lithium treatment may also be associated with persistent hyperparathyroidism and hypercalcaemia, as well as with hypermagnesaemia. Overweight of up to 4-10 kg is found in approximately 30% of lithium-treated patients. Most neurological manifestations are benign, for example, the fine postural and/or action tremor present in 4-20% of patients. This is increased by high caffeine consumption and concomitant use of other psychotropic agents. A number of rare, potentially serious neurological adverse effects have been reported, including extrapyramidal symptoms, 'pseudotumour cerebri' or occasionally cerebellar symptoms. Severe neurological sequelae are exceptional. Cognitive disturbances are often mentioned as a lithium-related adverse effect. The few controlled studies do show a statistically significant negative effect of lithium on memory, vigilance, reaction time and tracking. There are frequent reports of mild effects of lithium on cognition at therapeutic serum concentrations. A number of deaths associated with lithium treatment have been reported. The most serious issue is that of non-accidental overdose, i.e. either long-term overdosage or acute overdose on long-term treatment. Progressive renal insufficiency, an exceptional complication of long-term lithium therapy, may also have a fatal outcome. In relation to pregnancy, lithium salts are rated as category D (positive evidence of risk). Therefore, prescription of lithium should be avoided during the first trimester of pregnancy unless the benefit to the mother exceeds the risk to the fetus. Although lithium transfer into breast milk is well established, the long-term fate of babies breast-fed by mothers receiving lithium therapy is unknown. Whether lithium therapy is safe in breast-feeding women is controversial. Although there is no absolute contraindication, it is known that the kidney is particularly sensitive to lithium just after birth. Intoxication in patients on long-term treatment with lithium in the absence of history of acute ingestion is not rare. Contributing factors include change in daily dose, long-term high dosage, kidney disease or drug interaction. In suspected cases, serum concentrations should be obtained early and repeatedly. In addition to supportive measures, haemodialysis is the treatment of choice for severe cases. Thorough knowledge of the limitations and drawbacks of lithium therapy is mandatory for its optimal use, especially at a time when its risk/benefit profile needs to be compared accurately with that of antiepileptic drugs and other mood stabilizing medications.
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Abstract
Lithium is widely used to treat bipolar disorder. Nephrogenic diabetes insipidus (NDI) is the most common adverse effect of lithium and occurs in up to 40% of patients. Renal lithium toxicity is characterized by increased water and sodium diuresis, which can result in mild dehydration, hyperchloremic metabolic acidosis and renal tubular acidosis. The concentrating defect and natriuretic effect develop within weeks of lithium initiation. After years of lithium exposure, full-blown nephropathy can develop, which is characterized by decreased glomerular filtration rate and chronic kidney disease. Here, we review the clinical and experimental evidence that the principal cell of the collecting duct is the primary target for the nephrotoxic effects of lithium, and that these effects are characterized by dysregulation of aquaporin 2. This dysregulation is believed to occur as a result of the accumulation of cytotoxic concentrations of lithium, which enters via the epithelial sodium channel (ENaC) on the apical membrane and leads to the inhibition of signaling pathways that involve glycogen synthase kinase type 3beta. Experimental and clinical evidence demonstrates the efficacy of the ENaC inhibitor amiloride for the treatment of lithium-induced NDI; however, whether this agent can prevent the long-term adverse effects of lithium is not yet known.
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Affiliation(s)
- Jean-Pierre Grünfeld
- Department of Nephrology, Necker Hospital, Université Paris Descartes, Paris, France.
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Kortenoeven MLA, Li Y, Shaw S, Gaeggeler HP, Rossier BC, Wetzels JFM, Deen PMT. Amiloride blocks lithium entry through the sodium channel thereby attenuating the resultant nephrogenic diabetes insipidus. Kidney Int 2009; 76:44-53. [PMID: 19367330 DOI: 10.1038/ki.2009.91] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Lithium therapy frequently induces nephrogenic diabetes insipidus; amiloride appears to prevent its occurrence in some clinical cases. Amiloride blocks the epithelial sodium channel (ENaC) located in the apical membrane of principal cells; hence one possibility is that ENaC is the main entry site for lithium and the beneficial effect of amiloride may be through inhibiting lithium entry. Using a mouse collecting duct cell line, we found that vasopressin caused an increase in Aquaporin 2 (AQP2) expression which was reduced by clinically relevant lithium concentrations similar to what is seen with in vivo models of this disease. Further amiloride or benzamil administration prevented this lithium-induced downregulation of AQP2. Amiloride reduced transcellular lithium transport, intracellular lithium concentration, and lithium-induced inactivation of glycogen synthase kinase 3beta. Treatment of rats with lithium downregulated AQP2 expression, reduced the principal-to-intercalated cell ratio, and caused polyuria, while simultaneous administration of amiloride attenuated all these changes. These results show that ENaC is the major entry site for lithium in principal cells both in vitro and in vivo. Blocking lithium entry with amiloride attenuates lithium-induced diabetes insipidus, thus providing a rationale for its use in treating this disorder.
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Affiliation(s)
- Marleen L A Kortenoeven
- Department of Physiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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Zhang Y, Nelson RD, Carlson NG, Kamerath CD, Kohan DE, Kishore BK. Potential role of purinergic signaling in lithium-induced nephrogenic diabetes insipidus. Am J Physiol Renal Physiol 2009; 296:F1194-201. [PMID: 19244398 DOI: 10.1152/ajprenal.90774.2008] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Lithium (Li)-induced nephrogenic diabetes insipidus (NDI) has been attributed to the increased production of renal prostaglandin (PG)E(2). Previously we reported that extracellular nucleotides (ATP/UTP), acting through P(2y2) receptor in rat medullary collecting duct (mCD), produce and release PGE(2). Hence we hypothesized that increased production of PGE(2) in Li-induced NDI may be mediated by enhanced purinergic signaling in the mCD. Sprague-Dawley rats were fed either control or Li-added diet for 14 or 21 days. Li feeding resulted in marked polyuria and polydipsia associated with a decrease in aquaporin (AQP)2 protein abundance in inner medulla ( approximately 20% of controls) and a twofold increase in urinary PGE(2). When acutely challenged ex vivo with adenosine 5'-O-(3-thiotriphosphate) (ATPgammaS), UTP, or ADP, mCD of Li-fed rats showed significantly higher increases (50-130% over control diet-fed rats) in PGE(2) production, indicating that more than one subtype of P(2y) receptor is involved. This was associated with a 3.4-fold increase in P(2y4), but not P(2y2), receptor mRNA expression in the inner medulla of Li-fed rats compared with control diet-fed rats. Confocal laser immunofluorescence microscopy revealed predominant localization of both P(2y2) and P(2y4) receptors in the mCD of control or Li diet-fed rats. Together, these data indicate that in Li-induced NDI 1) purinergic signaling in the mCD is sensitized with increased production of PGE(2) and 2) P(2y2) and/or P(2y4) receptors may be involved in the enhanced purinergic signaling. Our study also reveals the potential beneficial effects of P(2y) receptor antagonists in the treatment and/or prevention of Li-induced NDI.
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Affiliation(s)
- Yue Zhang
- Nephrology Research (151M VA SCL Health Care System, 500 Foothill Dr., Salt Lake City, UT 84148. )
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Affiliation(s)
- Tae-Hwan Kwon
- Water and Salt Research Center, Institute of Anatomy, University of Aarhus, 8000 Aarhus C, Denmark
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Bouley R, Hasler U, Lu HAJ, Nunes P, Brown D. Bypassing vasopressin receptor signaling pathways in nephrogenic diabetes insipidus. Semin Nephrol 2008; 28:266-78. [PMID: 18519087 DOI: 10.1016/j.semnephrol.2008.03.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Water reabsorption in the kidney represents a critical physiological event in the maintenance of body water homeostasis. This highly regulated process relies largely on vasopressin (VP) action and on the VP-sensitive water channel (AQP2) that is expressed in principal cells of the kidney collecting duct. Defects in the VP signaling pathway and/or in AQP2 cell surface expression can lead to an inappropriate reduction in renal water reabsorption and the development of nephrogenic diabetes insipidus, a disease characterized by polyuria and polydipsia. This review focuses on the major regulatory steps that are involved in AQP2 trafficking and function. Specifically, we begin with a discussion on VP-receptor-independent mechanisms of AQP2 trafficking, with special emphasis on the nitric oxide-cyclic guanosine monophosphate signaling pathway, followed by a review of the mechanisms that govern AQP2 endocytosis and exocytosis. We then discuss emerging data illustrating roles played by the actin cytoskeleton on AQP2 trafficking, and lastly we consider elements that affect AQP2 protein expression in cells. Recent advances in each topic are summarized and are presented in the context of their potential to serve as a basis for the development of novel therapies that may ultimately improve life quality of nephrogenic diabetes insipidus patients.
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Affiliation(s)
- Richard Bouley
- Massachusetts General Hospital-Center for Systems Biology, Program in Membrane Biology and Nephrology Division, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
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Dysregulation of renal aquaporins and epithelial sodium channel in lithium-induced nephrogenic diabetes insipidus. Semin Nephrol 2008; 28:227-44. [PMID: 18519084 DOI: 10.1016/j.semnephrol.2008.03.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Lithium is used commonly to treat bipolar mood disorders. In addition to its primary therapeutic effects in the central nervous system lithium has a number of side effects in the kidney. The side effects include nephrogenic diabetes insipidus with polyuria, mild sodium wasting, and changes in acid/base balance. These functional changes are associated with marked structural changes in collecting duct cell composition and morphology, likely contributing to the functional changes. Over the past few years, investigations of lithium-induced renal changes have provided novel insight into the molecular mechanisms that are responsible for the disturbances in water, sodium, and acid/base metabolism. This includes dysregulation of renal aquaporins, epithelial sodium channel, and acid/base transporters. This review focuses on these issues with the aim to present this in context with clinically relevant features.
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Schliebe N, Strotmann R, Busse K, Mitschke D, Biebermann H, Schomburg L, Köhrle J, Bär J, Römpler H, Wess J, Schöneberg T, Sangkuhl K. V2 vasopressin receptor deficiency causes changes in expression and function of renal and hypothalamic components involved in electrolyte and water homeostasis. Am J Physiol Renal Physiol 2008; 295:F1177-90. [PMID: 18715941 DOI: 10.1152/ajprenal.00465.2007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Polyuria, hypernatremia, and hypovolemia are the major clinical signs of inherited nephrogenic diabetes insipidus (NDI). Hypernatremia is commonly considered a secondary sign caused by the net loss of water due to insufficient insertion of aquaporin-2 water channels into the apical membrane of the collecting duct cells. In the present study, we employed transcriptome-wide expression analysis to study gene expression in V2 vasopressin receptor (Avpr2)-deficient mice, an animal model for X-linked NDI. Gene expression changes in NDI mice indicate increased proximal tubular sodium reabsorption. Expression of several key genes including Na+-K+-ATPase and carbonic anhydrases was increased at the mRNA levels and accompanied by enhanced enzyme activities. In addition, altered expression was also observed for components of the eicosanoid and thyroid hormone pathways, including cyclooxygenases and deiodinases, in both kidney and hypothalamus. These effects are likely to contribute to the clinical NDI phenotype. Finally, our data highlight the involvement of the renin-angiotensin-aldosterone system in NDI pathophysiology and provide clues to explain the effectiveness of diuretics and indomethacin in the treatment of NDI.
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Affiliation(s)
- Nicole Schliebe
- Institute of Biochemistry, Molecular Biochemistry, Medical Faculty, University of Leipzig, Johannisallee 30, 04103 Leipzig, Germany
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Bedford JJ, Leader JP, Jing R, Walker LJ, Klein JD, Sands JM, Walker RJ. Amiloride restores renal medullary osmolytes in lithium-induced nephrogenic diabetes insipidus. Am J Physiol Renal Physiol 2008; 294:F812-20. [DOI: 10.1152/ajprenal.00554.2007] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In lithium-induced nephrogenic diabetes insipidus (NDI), alterations in renal medullary osmolyte concentrations have been assumed but never investigated. Amiloride can modify lithium-induced NDI, but the impact of amiloride in lithium-induced NDI on renal medullary osmolytes, aquaporins, and urea transporters is unknown and is the basis of this study. Rats fed lithium (60 mmol/kg dry food) over 4 wk developed NDI. Urine osmolality fell to 287 ± 19 mosmol/kgH2O (controls 1,211 ± 90 mosmol/kgH2O). Organic osmolytes in the renal medulla showed significant decreases compared with controls [inositol 221 ± 35 to 85 ± 10 mmol/kg protein; sorbitol 35 ± 9 to 3 ± 1 mmol/kg protein; glycerophosphorylcholine (GPC) 352 ± 80 to 91 ± 20 mmol/kg protein; and glycine betaine 69 ± 11 to 38 ± 38 mmol/kg protein]. Medullary urea content fell from 2,868 ± 624 to 480 ± 117 mmol/kg protein. Concurrent administration of amiloride (0.2 mmol/l) in the drinking water restored urine osmolality (1,132 ± 154 mosmol/kgH2O), and reduced urine volume. Medullary osmolyte content were restored to control values (inositol, 232 ± 12; sorbitol 32 ± 6; GPC, 244 ± 26; glycine betaine, 84 ± 5 mmol/kg protein). Medullary urea rose to 2,122 ± 305 mmol/kg protein. Reduced AQP2, AQP3, and urea transporter (UT-A1) expression was significantly reversed following amiloride therapy. Data presented here provide further understanding of how amiloride may substantially restore the lithium-induced impaired renal concentrating mechanism.
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Fröhlich O, Aggarwal D, Klein JD, Kent KJ, Yang Y, Gunn RB, Sands JM. Stimulation of UT-A1-mediated transepithelial urea flux in MDCK cells by lithium. Am J Physiol Renal Physiol 2008; 294:F518-24. [PMID: 18171999 DOI: 10.1152/ajprenal.00349.2007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Trans-epithelial tracer urea flux across Madin-Darby canine kidney (MDCK) cells permanently expressing the urea transporter UT-A1 is stimulated by agents that activate the cAMP signaling pathway, such as vasopressin or forskolin, thus mimicking the activation of urea permeability in the inner medullary collecting duct in the presence of vasopressin. Here, we report that UT-A1-mediated urea flux is also activated two-to-threefold over background by exposing the cells to media containing LiCl. This is in contrast to reports on cortical and medullary collecting duct tubules where acute and chronic exposure to lithium (Li) suppresses the osmotic water permeability, which is also regulated by cAMP levels. The Li concentration dependence of urea flux activation was linear up to 150 mM Li. Li activated only from the basolateral side where its effect was inhibited by amiloride, presumably because Li entered the cells through a basolateral Na-H exchanger. Li and IBMX, which also weakly activated urea flux, greatly augmented each others' stimulatory effect on urea flux. However, cellular cAMP levels did not rise commensurately with urea fluxes, and even though Li augments the activation by forskolin, it greatly inhibits the forskolin-induced formation of cAMP. These results suggest that the effect of Li in this MDCK model of renal cells does not involve cAMP or at least utilizes an additional signaling pathway independent of cAMP.
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Affiliation(s)
- Otto Fröhlich
- Department of Physiology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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Kwon TH. Dysregulation of Renal Cyclooxygenase-2 in Rats with Lithium-induced Nephrogenic Diabetes Insipidus. Electrolyte Blood Press 2007; 5:68-74. [PMID: 24459504 PMCID: PMC3894518 DOI: 10.5049/ebp.2007.5.2.68] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2007] [Accepted: 10/15/2007] [Indexed: 01/01/2023] Open
Abstract
This study aimed to examine whether the expression of major prostaglandin E2 (PGE2) synthesis enzyme, cyclooxygenase-2 (COX-2), is changed in the kidneys of the rats with lithium-induced nephrogenic diabetes insipidus (Li-NDI). Sprague-Dawley rats treated with lithium for 4 weeks were used as the NDI model and expression of renal COX-2 was determined by immunoblotting and immunohistochemistry. In Li-NDI where urine output was markedly increased and urine osmolality was significantly decreased, COX-2 expression in the inner medulla was decreased (28% of control), while it increased 18-fold in the cortex and outer medulla. Consistent with this, labeling intensity of COX-2 in macula densa region was increased, whereas it was decreased in the interstitial cells in the inner medulla, indicating a differential regulation of COX-2 between the cortex and inner medulla in Li-NDI. Accordingly, urinary PGE2 excretion was significantly increased in Li-NDI. In conclusion, there is a differential regulation of COX-2 between cortex and inner medulla in Li-NDI and urinary PGE2 excretion is increased in Li-NDI, possibly due to an increased renal production. This may suggest that increased renal production of PGE2 could play a role in modulating water reabsorption in the renal collecting duct in Li-NDI.
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Affiliation(s)
- Tae-Hwan Kwon
- Department of Biochemistry and Cell Biology, Kyungpook National University School of Medicine, Daegu, Korea
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Nørregaard R, Jensen BL, Topcu SO, Diget M, Schweer H, Knepper MA, Nielsen S, Frøkiaer J. COX-2 activity transiently contributes to increased water and NaCl excretion in the polyuric phase after release of ureteral obstruction. Am J Physiol Renal Physiol 2007; 292:F1322-33. [PMID: 17229676 DOI: 10.1152/ajprenal.00394.2006] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Release of bilateral ureteral obstruction (BUO) is associated with reduced expression of renal aquaporins (AQPs), polyuria, and impairment of urine-concentrating capacity. Recently, we demonstrated that 24 h of BUO is associated with increased cyclooxygenase (COX)-2 expression in the inner medulla (IM) and that selective COX-2 inhibition prevents downregulation of AQP2. In the present study, we tested the hypothesis that COX-2 activity increases in the postobstructive phase and that this increase in COX-2 activity contributes to polyuria and impaired urine-concentrating capacity. We examined the effect of the selective COX-2 inhibitor parecoxib (5 mg.kg(-1).day(-1) via osmotic minipumps) on renal functions and protein abundance of AQP2, AQP3, Na-K-2Cl cotransporter type 2 (NKCC2), and Na-K-ATPase 3 days after release of BUO. At 3 days after release of BUO, rats exhibited polyuria, dehydration and urine and IM tissue osmolality were decreased. There were inverse changes of COX-1 and COX-2 in the IM: COX-2 mRNA, protein, and activity increased, while COX-1 mRNA and protein decreased. Parecoxib reduced urine output 1 day after release of BUO, but sodium excretion and glomerular filtration rate were unchanged. Parecoxib normalized urinary PGE(2) and PGI(2) excretion and attenuated downregulation of AQP2 and AQP3, while phosphorylated AQP2 and NKCC2 remained suppressed. Parecoxib did not improve urine-concentrating capacity in response to 24 h of water deprivation. We conclude that decreased NKCC2 and collapse of the IM osmotic gradient, together with suppressed phosphorylated AQP2, are likely causes for the impaired urine-concentrating capacity and that COX-2 activity is not likely to mediate these changes in the chronic postobstructive phase after ureteral obstruction.
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Affiliation(s)
- Rikke Nørregaard
- The Water and Salt Research Center, University of Aarhus, DK-8200 Aarhus N, Denmark
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Blikslager AT, Yin C, Cochran AM, Wooten JG, Pettigrew A, Belknap JK. Cyclooxygenase Expression in the Early Stages of Equine Laminitis: A Cytologic Study. J Vet Intern Med 2006. [DOI: 10.1111/j.1939-1676.2006.tb00721.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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Robben JH, Knoers NVAM, Deen PMT. Cell biological aspects of the vasopressin type-2 receptor and aquaporin 2 water channel in nephrogenic diabetes insipidus. Am J Physiol Renal Physiol 2006; 291:F257-70. [PMID: 16825342 DOI: 10.1152/ajprenal.00491.2005] [Citation(s) in RCA: 146] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
In the renal collecting duct, water reabsorption is regulated by the antidiuretic hormone vasopressin (AVP). Binding of this hormone to the vasopressin V2 receptor (V2R) leads to insertion of aquaporin-2 (AQP2) water channels in the apical membrane, thereby allowing water reabsorption from the pro-urine to the interstitium. The disorder nephrogenic diabetes insipidus (NDI) is characterized by the kidney's inability to concentrate pro-urine in response to AVP, which is mostly acquired due to electrolyte disturbances or lithium therapy. Alternatively, NDI is inherited in an X-linked or autosomal fashion due to mutations in the genes encoding V2R or AQP2, respectively. This review describes the current knowledge of the cell biological causes of NDI and how these defects may explain the patients' phenotypes. Also, the increased understanding of these cellular defects in NDI has opened exciting initiatives in the development of novel therapies for NDI, which are extensively discussed in this review.
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MESH Headings
- Amino Acid Sequence
- Aquaporin 2/genetics
- Aquaporin 2/physiology
- DNA/genetics
- Diabetes Insipidus, Nephrogenic/etiology
- Diabetes Insipidus, Nephrogenic/genetics
- Diabetes Insipidus, Nephrogenic/physiopathology
- Diabetes Insipidus, Nephrogenic/therapy
- Gene Expression Regulation/physiology
- Genetic Diseases, X-Linked/etiology
- Genetic Diseases, X-Linked/genetics
- Genetic Diseases, X-Linked/physiopathology
- Genetic Diseases, X-Linked/therapy
- Humans
- Molecular Sequence Data
- Mutation/genetics
- Mutation/physiology
- Receptors, Vasopressin/genetics
- Receptors, Vasopressin/physiology
- Vasopressins/physiology
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Affiliation(s)
- Joris H Robben
- Department of Physiology, Nijmegen Centre for Molecular Life Sciences and Human Genetics, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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Theilig F, Debiec H, Nafz B, Ronco P, Nüsing R, Seyberth HW, Pavenstädt H, Bouby N, Bachmann S. Renal cortical regulation of COX-1 and functionally related products in early renovascular hypertension (rat). Am J Physiol Renal Physiol 2006; 291:F987-94. [PMID: 16788145 DOI: 10.1152/ajprenal.00099.2006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Renal volume regulation is modulated by the action of cyclooxygenases (COX) and the resulting generation of prostanoids. Epithelial expression of COX isoforms in the cortex directs COX-1 to the distal convolutions and cortical collecting duct, and COX-2 to the thick ascending limb. Partly colocalized are prostaglandin E synthase (PGES), the downstream enzyme for renal prostaglandin E(2) (PGE(2)) generation, and the EP receptors type 1 and 3. COX-1 and related components were studied in two kidney-one clip (2K1C) Goldblatt hypertensive rats with combined chronic ANG II or bradykinin B(2) receptor blockade using candesartan (cand) or the B(2) antagonist Hoechst 140 (Hoe). Rats (untreated sham, 2K1C, sham + cand, 2K1C + cand, sham + Hoe, 2K1C + Hoe) were treated to map expression of parameters controlling PGE(2) synthesis. In 2K1C, cortical COX isoforms did not change uniformly. COX-2 changed in parallel with NO synthase 1 (NOS1) expression with a raise in the clipped, but a decrease in the nonclipped side. By contrast, COX-1 and PGES were uniformly downregulated in both kidneys, along with reduced urinary PGE(2) levels, and showed no clear relations with the NO status. ANG II receptor blockade confirmed negative regulation of COX-2 by ANG II but blunted the decrease in COX-1 selectively in nonclipped kidneys. B(2) receptor blockade reduced COX-2 induction in 2K1C but had no clear effect on COX-1. We suggest that in 2K1C, COX-1 and PGES expression may fail to oppose the effects of renovascular hypertension through reduced prostaglandin signaling in late distal tubule and cortical collecting duct.
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MESH Headings
- Adrenergic beta-Antagonists/pharmacology
- Angiotensin II Type 1 Receptor Blockers/pharmacology
- Animals
- Benzimidazoles/pharmacology
- Biphenyl Compounds
- Blood Pressure/physiology
- Bradykinin/analogs & derivatives
- Bradykinin/pharmacology
- Cyclic GMP/metabolism
- Cyclooxygenase 1/genetics
- Cyclooxygenase 1/metabolism
- Cyclooxygenase 2/genetics
- Cyclooxygenase 2/metabolism
- Dinoprostone/urine
- Disease Models, Animal
- Hypertension, Renovascular/metabolism
- Hypertension, Renovascular/physiopathology
- Kidney Cortex/enzymology
- Kidney Tubules, Collecting/enzymology
- Kidney Tubules, Distal/enzymology
- Loop of Henle/enzymology
- Male
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Nitric Oxide/metabolism
- Nitric Oxide Synthase/metabolism
- Nitric Oxide Synthase Type I
- Rats
- Rats, Sprague-Dawley
- Receptors, Prostaglandin E/genetics
- Receptors, Prostaglandin E/metabolism
- Receptors, Prostaglandin E, EP1 Subtype
- Receptors, Prostaglandin E, EP3 Subtype
- Surgical Instruments
- Tetrazoles/pharmacology
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Affiliation(s)
- F Theilig
- Charité Universitätsmedizin Berlin, Institut für Vegetative Anatomie, Philippstr. 12, 10115 Berlin, Germany
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Li Y, Shaw S, Kamsteeg EJ, Vandewalle A, Deen PMT. Development of lithium-induced nephrogenic diabetes insipidus is dissociated from adenylyl cyclase activity. J Am Soc Nephrol 2006; 17:1063-72. [PMID: 16495377 DOI: 10.1681/asn.2005080884] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
In antidiuresis, vasopressin (AVP) occupation of V2 receptors in renal collecting ducts activates adenylyl cyclase, resulting in increased intracellular cAMP levels, which activates protein kinase A (PKA). PKA phosphorylates both the cAMP responsive element binding protein, which induces aquaporin-2 (AQP2) transcription, and AQP2, which then is translocated to the apical membrane, allowing urine concentration. Lithium treatment often causes nephrogenic diabetes insipidus (NDI), which coincides with decreased AQP2 expression and which generally is ascribed to reduced adenylyl cyclase activity. However, the underlying mechanism by which lithium causes NDI is poorly understood. This study demonstrated that the mouse cortical collecting duct mpkCCD(c14) cells are a good model; the deamino-8 D-arginine vasopressin (dDAVP)-induced endogenous AQP2 expression and plasma membrane localization was time-dependently reduced by treatment with clinically relevant lithium concentrations. Lithium did not affect AQP2 stability but decreased its mRNA levels. Surprising, the effect of lithium was cAMP independent; it did not alter AVP-stimulated cAMP production or PKA-dependent phosphorylation of AQP2 or cAMP responsive element binding protein. In vivo, kidney tissue of rats with lithium-induced NDI indeed generated less dDAVP-induced cAMP than that of controls, but this could be due to elevated blood AVP levels in rats with lithium-induced NDI. Indeed, Brattleboro rats, which lack endogenous AVP, with clamped blood dDAVP levels, showed no difference in dDAVP-generated cAMP generation between kidneys of rats with lithium-induced NDI and control rats. In conclusion, the first proper cell model to study lithium-induced NDI was developed, and it was demonstrated that the lithium-induced downregulation of AQP2 and development of NDI occur independent of adenylyl cyclase activity in vitro and in vivo.
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Affiliation(s)
- Yuedan Li
- Department of Physiology, 286 Nijmegen Center for Molecular Life Sciences, RUNMC Nijmegen, PO Box 9101, 6500 HB Nijmegen, The Netherlands
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Warford-Woolgar L, Peng CYC, Shuhyta J, Wakefield A, Sankaran D, Ogborn M, Aukema HM. Selectivity of cyclooxygenase isoform activity and prostanoid production in normal and diseased Han:SPRD-cy rat kidneys. Am J Physiol Renal Physiol 2005; 290:F897-904. [PMID: 16234308 DOI: 10.1152/ajprenal.00332.2005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Renal prostanoids are important regulators of normal renal function and maintenance of renal homeostasis. In diseased kidneys, renal cylooxygenase (COX) expression and prostanoid formation are altered. With the use of the Han:Sprague-Dawley-cy rat, the aim of this study was to determine the relative contribution of renal COX isoforms (protein, gene expression, and activity) on renal prostanoid production [thromboxane B(2) (TXB(2), stable metabolite of TXA(2)), prostaglandin E(2) (PGE(2)), and 6-keto-prostaglandin F(1alpha) (6-keto-PGF(1alpha), stable metabolite of PGI(2))] in normal and diseased kidneys. In diseased kidneys, COX-1-immunoreactive protein and mRNA levels were higher and COX-2 levels were lower compared with normal kidneys. In contrast, COX activities were higher in diseased compared with normal kidneys for both COX-1 [0.05 +/- 0.02 vs. 0.45 +/- 0.11 ng prostanoids x min(-1) x mg protein(-1) (P < 0.001)] and COX-2 [0.64 +/- 0.10 vs. 2.32 +/- 0.22 ng prostanoids x min(-1).mg protein(-1) (P < 0.001)]. As the relative difference in activity was greater for COX-1, the ratio of COX-1/COX-2 was higher in diseased compared with normal kidneys, although the predominant activity was still due to the COX-2 isoform in both genotypes. Endogenous and steady-state in vitro levels of prostanoids were approximately 2-10 times higher in diseased compared with normal kidneys. The differences between normal and diseased kidney prostanoids were in the order of TXB(2) > 6-keto-PGF(1alpha) > PGE(2), as determined by higher renal prostanoid levels and COX activity ratios of TXB(2)/6-keto-PGF(1alpha), TXB(2)/PGE(2), and 6-keto-PGF(1alpha)/PGE(2). This specificity in both the COX isoform type and for the prostanoids produced has implications for normal and diseased kidneys in treatments involving selective inhibition of COX isoforms.
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Affiliation(s)
- Lori Warford-Woolgar
- Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, Canada
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