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Orellana JM, Kampe K, Schulze F, Sieber J, Jehle AW. Fetuin-A aggravates lipotoxicity in podocytes via interleukin-1 signaling. Physiol Rep 2018; 5:e13287. [PMID: 28554965 PMCID: PMC5449566 DOI: 10.14814/phy2.13287] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 04/26/2017] [Indexed: 12/27/2022] Open
Abstract
Sterile inflammation is considered critical in the pathogenesis of diabetic nephropathy (DN). Here we show that Fetuin-A (FetA) or lipopolysaccharide (LPS) exacerbate palmitic acid-induced podocyte death, which is associated with a strong induction of monocyte chemoattractant protein-1 (MCP-1) and keratinocyte chemoattractant (KC). Moreover, blockage of TLR4 prevents MCP-1 and KC secretion and attenuates podocyte death induced by palmitic acid alone or combined with FetA. In addition, inhibition of interleukin-1 (IL-1) signaling by anakinra, a recombinant human IL-1Ra, or a murinized anti-IL-1β antibody attenuates the inflammatory and ultimate cell death response elicited by FetA alone or combined with palmitic acid. In vivo short-term therapy of diabetic DBA/2J mice with an anti-IL1-β antibody for 4 weeks prevented an increase in serum FetA and considerably decreased urinary tumor necrosis alpha (TNF-α), a known risk factor for DN progression. In summary, our results suggest that FetA similarly to LPS leads to an inflammatory response in podocytes, which exacerbates palmitic acid-induced podocyte death and our data imply a critical role for IL-1β signaling in this process. The study offers the rational for prolonged in vivo studies aimed at testing anti-IL-1β therapy for prevention and treatment of DN.
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Affiliation(s)
- Jana M Orellana
- Department of Biomedicine, Molecular Nephrology, University Hospital, Basel, Switzerland
| | - Kapil Kampe
- Department of Biomedicine, Molecular Nephrology, University Hospital, Basel, Switzerland
| | - Friederike Schulze
- Department of Biomedicine, Diabetes Research, University Hospital, Basel, Switzerland
| | - Jonas Sieber
- Department of Biomedicine, Molecular Nephrology, University Hospital, Basel, Switzerland.,Harvard Medical School and Division of Nephrology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Andreas W Jehle
- Department of Biomedicine, Molecular Nephrology, University Hospital, Basel, Switzerland.,Department of Internal Medicine, Transplantation Immunology and Nephrology, University Hospital, Basel, Switzerland
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Ding F, Wickman L, Wang SQ, Zhang Y, Wang F, Afshinnia F, Hodgin J, Ding J, Wiggins RC. Accelerated podocyte detachment and progressive podocyte loss from glomeruli with age in Alport Syndrome. Kidney Int 2017; 92:1515-1525. [PMID: 28754557 PMCID: PMC5696060 DOI: 10.1016/j.kint.2017.05.017] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 04/12/2017] [Accepted: 05/04/2017] [Indexed: 01/15/2023]
Abstract
Podocyte depletion is a common mechanism driving progression in glomerular diseases. Alport Syndrome glomerulopathy, caused by defective α3α4α5 (IV) collagen heterotrimer production by podocytes, is associated with an increased rate of podocyte detachment detectable in urine and reduced glomerular podocyte number suggesting that defective podocyte adherence to the glomerular basement membrane might play a role in driving progression. Here a genetically phenotyped Alport Syndrome cohort of 95 individuals [urine study] and 41 archived biopsies [biopsy study] were used to test this hypothesis. Podocyte detachment rate (measured by podocin mRNA in urine pellets expressed either per creatinine or 24-hour excretion) was significantly increased 11-fold above control, and prior to a detectably increased proteinuria or microalbuminuria. In parallel, Alport Syndrome glomeruli lose an average 26 podocytes per year versus control glomeruli that lose 2.3 podocytes per year, an 11-fold difference corresponding to the increased urine podocyte detachment rate. Podocyte number per glomerulus in Alport Syndrome biopsies is projected to be normal at birth (558/glomerulus) but accelerated podocyte loss was projected to cause end-stage kidney disease by about 22 years. Biopsy data from two independent cohorts showed a similar estimated glomerular podocyte loss rate comparable to the measured 11-fold increase in podocyte detachment rate. Reduction in podocyte number and density in biopsies correlated with proteinuria, glomerulosclerosis, and reduced renal function. Thus, the podocyte detachment rate appears to be increased from birth in Alport Syndrome, drives the progression process, and could potentially help predict time to end-stage kidney disease and response to treatment.
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Affiliation(s)
- Fangrui Ding
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Larysa Wickman
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan, USA
| | - Su Q Wang
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Yanqin Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Fang Wang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Farsad Afshinnia
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Jeffrey Hodgin
- Department of Pathology, University of Michigan, Ann Arbor, Michigan, USA
| | - Jie Ding
- Department of Pediatrics, Peking University First Hospital, Beijing, China.
| | - Roger C Wiggins
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA.
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53
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Kostovska I, Trajkovska KT, Cekovska S, Spasovski G, Labudovic D. Nephrin and Podocalyxin - New Podocyte Proteins for Early Detection of Secondary Nephropathies. BANTAO JOURNAL 2017. [DOI: 10.1515/bj-2016-0003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Abstract
In the last two decades a great progress was observed in understanding of podocytes, their specific structure and function identifying many specific podocyte proteins, such as nephrin and podocalyxin. Podocytes form the final barrier to plasma proteins leakage. Nephrin as a main component of the filtration diaphragm forms a physical barrier while podocalyxin as sialoglycoprotein forms an electrostatic barrier. Podocyte damage, i.e. podocytopathies and their loss through urine-podocyturia, are crucial in pathogenesis and progression of nephropathies with proteinuria as main clinical manifestation. In podocytopathies, nephrin and podocalyxin appear in the urine before proteinuria and microalbuminuria which were previously considered as earliest markers of nephropathies. Nephrinuria and podocalyxuria indicate damage of the podocytes on glomerular level and/or presence of apoptotic and necrotic podocytes in urine. These urinary markers are also important in early diagnosis of secondary nephropathies such as diabetic, lupus and hypertensive nephropathy as the most common causes of end-stage renal failure (ESRF). These markers are also important in the prediction of preeclampsia, which is the most common complication in pregnancy. In this review we elaborate in dept the main structural and functional features of podocytes and their specific proteins, nephrin and podocalyxin, summarizing the recent literature data on their importance in the early diagnosis of the most common secondary nephropathies.
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Affiliation(s)
- Irena Kostovska
- Department of Medical and Experimental Biochemistry, Skopje , Republic of Macedonia
| | | | - Svetlana Cekovska
- Department of Medical and Experimental Biochemistry, Skopje , Republic of Macedonia
| | - Goce Spasovski
- Department of Nephrology, Medical Faculty, Skopje, University "Ss Cyril and Methodius", Skopje , Republic of Macedonia
| | - Danica Labudovic
- Department of Medical and Experimental Biochemistry, Skopje , Republic of Macedonia
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Wang L, Sha Y, Bai J, Eisner W, Sparks MA, Buckley AF, Spurney RF. Podocyte-specific knockout of cyclooxygenase 2 exacerbates diabetic kidney disease. Am J Physiol Renal Physiol 2017; 313:F430-F439. [PMID: 28490532 DOI: 10.1152/ajprenal.00614.2016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 05/02/2017] [Accepted: 05/09/2017] [Indexed: 01/11/2023] Open
Abstract
Enhanced expression of cyclooxygenase 2 (COX2) in podocytes contributes to glomerular injury in diabetic kidney disease, but some basal level of podocyte COX2 expression might be required to promote podocyte attachment and/or survival. To investigate the role of podocyte COX2 expression in diabetic kidney disease, we deleted COX2 specifically in podocytes in a mouse model of Type 1 diabetes mellitus (Akita mice). Podocyte-specific knockout (KO) of COX2 did not affect renal morphology or albuminuria in nondiabetic mice. Albuminuria was significantly increased in wild-type (WT) and KO Akita mice compared with nondiabetic controls, and the increase in albuminuria was significantly greater in KO Akita mice compared with WT Akita mice at both 16 and 20 wk of age. At the 20-wk time point, mesangial expansion was also increased in WT and KO Akita mice compared with nondiabetic animals, and these histologic abnormalities were not improved by KO of COX2. Tubular injury was seen only in diabetic mice, but there were no significant differences between groups. Thus, KO of COX2 enhanced albuminuria and did not improve the histopathologic features of diabetic kidney disease. These data suggest that 1) KO of COX2 in podocytes does not ameliorate diabetic kidney disease in Akita mice, and 2) some basal level of podocyte COX2 expression in podocytes is necessary to attenuate the adverse effects of diabetes on glomerular filtration barrier function.
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Affiliation(s)
- Liming Wang
- Division of Nephrology, Department of Medicine, Duke University and Durham Veterans Affairs Medical Centers, Durham, North Carolina
| | - Yonggang Sha
- Division of Hematologic Malignancies and Cellular Therapy, Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | | | - William Eisner
- Division of Hematological Malignancies, Department of Medicine, Duke University Medical Center, Durham, North Carolina; and
| | - Matthew A Sparks
- Division of Nephrology, Department of Medicine, Duke University and Durham Veterans Affairs Medical Centers, Durham, North Carolina
| | - Anne F Buckley
- Department of Pathology, Duke University Medical Center, Durham, North Carolina
| | - Robert F Spurney
- Division of Nephrology, Department of Medicine, Duke University and Durham Veterans Affairs Medical Centers, Durham, North Carolina;
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Luna-Antonio BI, Rodriguez-Muñoz R, Namorado-Tonix C, Vergara P, Segovia J, Reyes JL. Gas1 expression in parietal cells of Bowman’s capsule in experimental diabetic nephropathy. Histochem Cell Biol 2017; 148:33-47. [DOI: 10.1007/s00418-017-1550-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/15/2017] [Indexed: 12/25/2022]
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Carlson EC, Chhoun JM, Grove BD, Laturnus DI, Zheng S, Epstein PN, Tan Y. Renoprotection From Diabetic Complications in OVE Transgenic Mice by Endothelial Cell Specific Overexpression of Metallothionein: A TEM Stereological Analysis. Anat Rec (Hoboken) 2017; 300:560-576. [PMID: 27813325 PMCID: PMC5309165 DOI: 10.1002/ar.23511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 11/01/2016] [Accepted: 11/01/2016] [Indexed: 01/23/2023]
Abstract
We previously demonstrated that OVE transgenic diabetic mice are susceptible to chronic complications of diabetic nephropathy (DN) including substantial oxidative damage to the renal glomerular filtration barrier (GFB). Importantly, the damage was mitigated significantly by overexpression of the powerful antioxidant, metallothionein (MT) in podocytes. To test our hypothesis that GFB damage in OVE mice is the result of endothelial oxidative insult, a new JTMT transgenic mouse was designed in which MT overexpression was targeted specifically to endothelial cells. At 60 days of age, JTMT mice were crossed with age-matched OVE diabetic mice to produce bi-transgenic OVE-JTMT diabetic progeny that carried the endothelial targeted JTMT transgene. Renal tissues from the OVE-JTMT progeny were examined by unbiased TEM stereometry for possible GFB damage and other alterations from chronic complications of DN. In 150 day-old OVE-JTMT mice, blood glucose and HbA1c were indistinguishable from age-matched OVE mice. However, endothelial-specific MT overexpression in OVE-JTMT mice mitigated several DN complications including significantly increased non-fenestrated glomerular endothelial area, and elimination of glomerular basement membrane thickening. Significant renoprotection was also observed outside of endothelial cells, including reduced podocyte effacement, and increased podocyte and total glomerular cell densities. Moreover, when compared to OVE diabetic animals, OVE-JTMT mice showed significant mitigation of nephromegaly, glomerular hypertrophy, increased mesangial cell numbers and increased total glomerular cell numbers. These results confirm the importance of oxidative stress to glomerular damage in DN, and show the central role of endothelial cell injury to the pathogenesis of chronic complications of diabetes. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 300:560-576, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Edward C. Carlson
- Department of Biomedical SciencesUniversity of North DakotaGrand ForksNorth Dakota
| | - Jennifer M. Chhoun
- Department of Biomedical SciencesUniversity of North DakotaGrand ForksNorth Dakota
| | - Bryon D. Grove
- Department of Biomedical SciencesUniversity of North DakotaGrand ForksNorth Dakota
| | - Donna I. Laturnus
- Department of Biomedical SciencesUniversity of North DakotaGrand ForksNorth Dakota
| | - Shirong Zheng
- Department of PediatricsUniversity of LouisvilleLouisvilleKentucky
| | - Paul N. Epstein
- Department of PediatricsUniversity of LouisvilleLouisvilleKentucky
| | - Yi Tan
- Department of PediatricsUniversity of LouisvilleLouisvilleKentucky
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Huang G, Zou B, Lv J, Li T, Huai G, Xiang S, Lu S, Luo H, Zhang Y, Jin Y, Wang Y. Notoginsenoside R1 attenuates glucose-induced podocyte injury via the inhibition of apoptosis and the activation of autophagy through the PI3K/Akt/mTOR signaling pathway. Int J Mol Med 2017; 39:559-568. [PMID: 28112381 PMCID: PMC5360354 DOI: 10.3892/ijmm.2017.2864] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 01/11/2017] [Indexed: 12/26/2022] Open
Abstract
Injury to terminally differentiated podocytes contributes ignificantly to proteinuria and glomerulosclerosis. The aim of this study was to examine the protective effects of notoginsenoside R1 (NR1) on the maintenance of podocyte number and foot process architecture via the inhibition of apoptosis, the induction of autophagy and the maintenance pf podocyte biology in target cells. The effects of NR1 on conditionally immortalized human podocytes under high glucose conditions were evaluated by determining the percentage apoptosis, the percentage autophagy and the expression levels of slit diaphragm proteins. Our results revealed that NR1 protected the podocytes against high glucose-induced injury by decreasing apoptosis, increasing autophagy and by promoting cytoskeletal recovery. The phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway was further investigated in order to elucidate the mechanisms responsible for the protective effects of NR1 on podocytes. Our data indicated that treatment with NR increased the phosphorylation levels of PI3K, Akt and mTOR, leading to the activation of the PI3K/Akt/mTOR signaling pathway in podocytes. To the best of our knowledge, this is the first in vitro study to demonstrate that NR1 protects podocytes by activating the PI3K/Akt/mTOR pathway.
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Affiliation(s)
- Guodong Huang
- Department of Nephrology, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi 530011, P.R. China
| | - Bingyu Zou
- Department of Gynecology, Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, Chengdu, Sichuan 610072, P.R. China
| | - Jianzhen Lv
- School of Basic Medical Science, Guangxi University of Chinese Medicine, Nanning, Guangxi 530001, P.R. China
| | - Tongyu Li
- School of Basic Medical Science, Guangxi University of Chinese Medicine, Nanning, Guangxi 530001, P.R. China
| | - Guoli Huai
- Department of Biomedical Engineering, Medical School of University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, P.R. China
| | - Shaowei Xiang
- Department of Nephrology, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi 530011, P.R. China
| | - Shilong Lu
- School of Basic Medical Science, Guangxi University of Chinese Medicine, Nanning, Guangxi 530001, P.R. China
| | - Huan Luo
- Department of Nephrology, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi 530011, P.R. China
| | - Yaping Zhang
- Department of Nephrology, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi 530011, P.R. China
| | - Yi Jin
- Center for Perinatal Research, Research Institute at Nationwide Children's Hospital, Columbus, OH 43215, USA
| | - Yi Wang
- Department of Biomedical Engineering, Medical School of University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, P.R. China
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58
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Dai H, Liu Q, Liu B. Research Progress on Mechanism of Podocyte Depletion in Diabetic Nephropathy. J Diabetes Res 2017; 2017:2615286. [PMID: 28791309 PMCID: PMC5534294 DOI: 10.1155/2017/2615286] [Citation(s) in RCA: 178] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 02/05/2017] [Accepted: 03/05/2017] [Indexed: 12/13/2022] Open
Abstract
Diabetic nephropathy (DN) together with glomerular hyperfiltration has been implicated in the development of diabetic microangiopathy in the initial stage of diabetic diseases. Increased amounts of urinary protein in DN may be associated with functional and morphological alterations of podocyte, mainly including podocyte hypertrophy, epithelial-mesenchymal transdifferentiation (EMT), podocyte detachment, and podocyte apoptosis. Accumulating studies have revealed that disruption in multiple renal signaling pathways had been critical in the progression of these pathological damages, such as adenosine monophosphate-activated kinase signaling pathways (AMPK), wnt/β-catenin signaling pathways, endoplasmic reticulum stress-related signaling pathways, mammalian target of rapamycin (mTOR)/autophagy pathway, and Rho GTPases. In this review, we highlight new molecular insights underlying podocyte injury in the progression of DN, which offer new therapeutic targets to develop important renoprotective treatments for DN over the next decade.
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Affiliation(s)
- Haoran Dai
- Department of Nephrology, Shunyi Branch, Beijing Hospital of Traditional Chinese Medicine, Station East 5, Shunyi District, Beijing 101300, China
| | - Qingquan Liu
- Department of Nephrology, Shunyi Branch, Beijing Hospital of Traditional Chinese Medicine, Station East 5, Shunyi District, Beijing 101300, China
- Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University, 23 Meishuguanhou Street, Dongcheng District, Beijing 100010, China
- *Qingquan Liu: and
| | - Baoli Liu
- Department of Nephrology, Shunyi Branch, Beijing Hospital of Traditional Chinese Medicine, Station East 5, Shunyi District, Beijing 101300, China
- Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University, 23 Meishuguanhou Street, Dongcheng District, Beijing 100010, China
- *Baoli Liu:
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59
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Dande RR, Peev V, Altintas MM, Reiser J. Soluble Urokinase Receptor and the Kidney Response in Diabetes Mellitus. J Diabetes Res 2017; 2017:3232848. [PMID: 28596971 PMCID: PMC5449757 DOI: 10.1155/2017/3232848] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Accepted: 03/19/2017] [Indexed: 12/20/2022] Open
Abstract
Diabetic nephropathy (DN) is the leading cause of end-stage renal disease (ESRD) worldwide. DN typically manifests by glomerular hyperfiltration and microalbuminuria; then, the disease progresses to impaired glomerular filtration rate, which leads to ESRD. Treatment options for DN include the strict control of blood glucose levels and pressure (e.g., intraglomerular hypertension). However, the search for novel therapeutic strategies is ongoing. These include seeking specific molecules that contribute to the development and progression of DN to potentially interfere with these "molecular targets" as well as with the cellular targets within the kidney such as podocytes, which play a major role in the pathogenesis of DN. Recently, podocyte membrane protein urokinase receptor (uPAR) and its circulating form (suPAR) are found to be significantly induced in glomeruli and sera of DN patients, respectively, and elevated suPAR levels predicted diabetic kidney disease years before the occurrence of microalbuminuria. The intent of this review is to summarize the emerging evidence of uPAR and suPAR in the clinical manifestations of DN. The identification of specific pathways that govern DN will help us build a more comprehensive molecular model for the pathogenesis of the disease that can inform new opportunities for treatment.
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Affiliation(s)
| | - Vasil Peev
- Rush University Medical Center, Chicago, IL, USA
| | - Mehmet M. Altintas
- Rush University Medical Center, Chicago, IL, USA
- *Mehmet M. Altintas: and
| | - Jochen Reiser
- Rush University Medical Center, Chicago, IL, USA
- *Jochen Reiser:
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60
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Zhang SS, Wu Z, Zhang Z, Xiong ZY, Chen H, Huang QB. Glucagon-like peptide-1 inhibits the receptor for advanced glycation endproducts to prevent podocyte apoptosis induced by advanced oxidative protein products. Biochem Biophys Res Commun 2016; 482:1413-1419. [PMID: 27965099 DOI: 10.1016/j.bbrc.2016.12.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 12/07/2016] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To investigate whether and how glucagon-like peptide-1 (GLP-1) can protect podocytes from apoptosis induced by advanced oxidative protein products (AOPPs). METHODS Murine podocytes were stimulated with 200 μg/ml AOPP for 48 h in the presence or absence of GLP-1. Cell viability was assessed using the cell counting kit-8 assay. Podocyte apoptosis was detected by flow cytometry and Hoechst 33258 staining. Superoxide radical production was assayed using lucigenin-enhanced chemiluminescence, and Western blotting was used to measure expression of RAGE, NADPH oxidase subunits p47phox and gp91phox, as well as apoptosis-associated proteins p53, Bax, Bcl-2 and caspase-3. RESULTS Incubating podocytes with AOPPs reduced cell viability, triggered changes in cell morphology and promoted apoptosis. GLP-1 partially inhibited AOPP-induced apoptosis, O2- overproduction, and AOPP-induced expression of RAGE. GLP-1 inhibited expression of p47phox and gp91phox in AOPP-treated podocytes, and it attenuated AOPP-induced expression of p53, Bax and cleaved caspase-3, whereas it restored expression of Bcl-2. CONCLUSION GLP-1 partially inhibits AOPP-induced apoptosis in podocytes, perhaps by interfering with the AOPP-RAGE axis, decreasing oxidative stress and inhibiting the downstream p53/Bax/caspase-3 apoptotic pathway. GLP-1 may be a useful anti-apoptotic agent for early intervention in diabetic nephropathy.
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Affiliation(s)
- Shuang-Shuang Zhang
- Department of Pathophysiology, Key Laboratory for Shock and Microcirculation Research of Guangdong Province, Southern Medical University, Guangzhou, China; Department of Endocrinology, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Zhou Wu
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Zhen Zhang
- Department of Endocrinology, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Zhou-Yi Xiong
- Department of Endocrinology, Yue Bei People's Hospital, Shaoguan, China
| | - Hong Chen
- Department of Endocrinology, Zhujiang Hospital, Southern Medical University, Guangzhou, China.
| | - Qiao-Bing Huang
- Department of Pathophysiology, Key Laboratory for Shock and Microcirculation Research of Guangdong Province, Southern Medical University, Guangzhou, China.
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61
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Zou XR, Wang XQ, Hu YL, Zhou HL. Effects of Shen'an granules on Wnt signaling pathway in mouse models of diabetic nephropathy. Exp Ther Med 2016; 12:3515-3520. [PMID: 28105085 PMCID: PMC5228428 DOI: 10.3892/etm.2016.3800] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 07/26/2016] [Indexed: 12/21/2022] Open
Abstract
The effect of Shen'an granules on the Wnt signaling pathway in renal tissues of mouse models of streptozotocin (STZ)-induced diabetic nephropathy was investigated in the present study. A total of 62 BALB/c mice were randomly divided into the normal control (A group), model (B group), losartan (C group), low-dose Shen'an granules (D group), and high-dose Shen'an granules (E group) groups. The mouse model of diabetic nephropathy was established by a single intraperitoneal injection of STZ (150 mg/kg). The animals were treated with drugs for 8 weeks, and blood creatinine, blood urea nitrogen, triglycerides (TG), and total cholesterol (CHOL) were measured prior to and after treatment. PAS staining was performed for observation of glomerular microstructure by light microscope, and western blot analysis was performed to detect Wnt1 protein and β-catenin protein. The results indicated that the quantification of 24-h microalbuminuria, and levels of blood creatinine, urea nitrogen, TG, and CHOL were significantly lower in the high- and low-dose Shen'an granules groups than those in the model group (p<0.05). The expression levels of Wnt1 protein and β-catenin protein in the high- and low-dose Shen'an granules groups were significantly lower than those in the model group (p<0.05). In conclusion, proteinuria, renal dysfunction, and dyslipidemias are closely associated with the abnormal activation of the Wnt signaling pathway in the mouse model of diabetic nephropathy. The mechanism by which Shen'an granules regulate proteinuria, renal function, and blood lipids may be associated with inhibition of the abnormally activated Wnt signaling pathway.
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Affiliation(s)
- Xin-Rong Zou
- Department of Nephrology, Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan, Hubei 430061, P.R. China
| | - Xiao-Qin Wang
- Department of Nephrology, Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan, Hubei 430061, P.R. China
| | - Ying-Lin Hu
- Department of Nephrology, Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan, Hubei 430061, P.R. China
| | - Hui-Lan Zhou
- Department of Nephrology, Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan, Hubei 430061, P.R. China
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Nair M, le Roux CW, Docherty NG. Mechanisms underpinning remission of albuminuria following bariatric surgery. Curr Opin Endocrinol Diabetes Obes 2016; 23:366-72. [PMID: 27584009 DOI: 10.1097/med.0000000000000279] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
PURPOSE OF REVIEW Albuminuria is a biomarker of renal injury commonly used to monitor progression of diabetic kidney disease. The appearance of excess albumin in the urine reflects alterations in the structure and permeability of the glomerular filtration barrier. The present article summarizes the clinical evidence base for remission of albuminuria after bariatric surgery. It furthermore focuses on how beneficial impacts on glomerular podocyte structure and function may explain this phenomenon. RECENT FINDINGS A coherent clinical evidence base is emerging demonstrating remission of albuminuria following bariatric surgery in patients with obesity and diabetes. The impaired metabolic milieu in diabetic kidney disease drives podocyte dedifferentiation and death through glucotoxic, lipotoxic proinflammatory, and pressure-related stress. Improvements in these parameters after surgery correlate with improvements in albuminuria and preclinical studies provide mechanistic data that support the existence of cause-effect relationship. SUMMARY The benefits of bariatric surgery extend beyond weight loss in diabetes to encompass beneficial effects on diabetic renal injury. Attenuation of the toxic metabolic milieu that the podocyte is exposed to postbariatric surgery suggests that the restitution of podocyte health is a key cellular event underpinning remission of albuminuria.
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Affiliation(s)
- Meera Nair
- aDiabetes Complications Research Centre, Conway Institute, School of Medicine and Medical Sciences, University College Dublin, Dublin, IrelandbDepartment of Gastrosurgical Research and Education, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, SwedencInvestigative Science, Imperial College London, London, UK
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The role of local IL6/JAK2/STAT3 signaling in high glucose-induced podocyte hypertrophy. Kidney Res Clin Pract 2016; 35:212-218. [PMID: 27957415 PMCID: PMC5143438 DOI: 10.1016/j.krcp.2016.09.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 09/06/2016] [Accepted: 09/13/2016] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Interleukin-6 (IL6) is an important regulator of cellular hypertrophy through the gp130/Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway. We tested the hypothesis that IL6 and its downstream gp130/JAK2/STAT3 pathway participated in high glucose (HG)-induced podocyte hypertrophy. METHODS IL6 levels in the media and lysates of podocytes were measured by enzyme-linked immunosorbent assay. Western blots were performed to determine the protein expression levels of gp130/JAK2/STAT3 among podocytes cultured with normal glucose (NG), NG + mannitol, NG + recombinant IL6, HG, and HG + IL6-neutralizing antibodies (IL6NAb). Immunoprecipitation was examined to determine whether gp130 interacted with JAK2 in response to HG or IL6. Podocyte hypertrophy was verified using protein/cell counts and flow cytometry. RESULTS IL6 levels were significantly increased in the media and lysates of podocytes cultured in HG compared with the NG groups. The nuclear phospho-STAT3/STAT3 ratio was increased by HG and NG + IL6 and was attenuated in the HG + IL6NAb groups, indicating that nuclear STAT3 was activated following JAK2 and cytosolic STAT3 activation in response to IL6 secreted by HG-stimulated podocytes. Immunoprecipitation showed increased phospho-JAK2 recruitment to gp130 in the HG and NG + IL6 groups, and the addition of IL6NAb in the HG group significantly abrogated these increases. Podocyte hypertrophy was significantly increased in the HG and NG + IL6 compared with the NG condition and was diminished by the addition of IL6NAbs to the HG group. CONCLUSION IL6 might play a prominent role in the local activation of JAK2/STAT3 in podocyte hypertrophy under HG conditions. In vivo studies examining this pathway are warranted.
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Effect of Tongxinluo on Podocyte Apoptosis via Inhibition of Oxidative Stress and P38 Pathway in Diabetic Rats. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2016; 2016:5957423. [PMID: 27672400 PMCID: PMC5031883 DOI: 10.1155/2016/5957423] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 08/03/2016] [Accepted: 08/08/2016] [Indexed: 12/19/2022]
Abstract
Diabetic nephropathy (DN) has been the leading cause of end-stage renal disease (ESRD). Podocyte apoptosis is a main mechanism of progression of DN. It has been demonstrated that activated P38 and caspase-3 induced by oxidative stress mainly account for increased podocyte apoptosis and proteinuria in DN. Meanwhile, Tongxinluo (TXL) can ameliorate renal structure disruption and dysfunction in DN patients in our clinical practice. However, the effect of TXL on podocyte apoptosis and P38 pathway remains unclear. To explore the effect of TXL on podocyte apoptosis and its molecular mechanism in DN, our in vivo and in vitro studies were performed. TXL attenuated oxidative stress in podocyte in DN in our in vivo and in vitro studies. Moreover, TXL inhibited the activation of P38 and caspase-3. Bcl-2 and Bax expression was partially restored by TXL treatment in our in vivo and in vitro studies. More importantly, TXL decreased podocyte apoptosis in diabetic rats and high glucose cultured podocyte. In conclusion, TXL protects podocyte from apoptosis in DN, partially through its antioxidant effect and inhibiting of the activation of P38 and caspase-3.
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Sun H, Wang W, Han P, Shao M, Song G, Du H, Yi T, Li S. Astragaloside IV ameliorates renal injury in db/db mice. Sci Rep 2016; 6:32545. [PMID: 27585918 PMCID: PMC5009300 DOI: 10.1038/srep32545] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 08/10/2016] [Indexed: 01/22/2023] Open
Abstract
Diabetic nephropathy is a lethal complication of diabetes mellitus and a major type of chronic kidney disease. Dysregulation of the Akt pathway and its downstream cascades, including mTOR, NFκB, and Erk1/2, play a critical role in the development of diabetic nephropathy. Astragaloside IV is a major component of Huangqi and exerts renal protection in a mouse model of type 1 diabetes. The current study was undertaken to investigate the protective effects of diet supplementation of AS-IV on renal injury in db/db mice, a type 2 diabetic mouse model. Results showed that administration of AS-IV reduced albuminuria, ameliorated changes in the glomerular and tubular pathology, and decreased urinary NAG, NGAL, and TGF-β1 in db/db mice. AS-IV also attenuated the diabetes-related activation of Akt/mTOR, NFκB, and Erk1/2 signaling pathways without causing any detectable hepatotoxicity. Collectively, these findings showed AS-IV to be beneficial to type 2 diabetic nephropathy, which might be associated with the inhibition of Akt/mTOR, NFκB and Erk1/2 signaling pathways.
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Affiliation(s)
- Huili Sun
- Department of Nephrology, Shenzhen Affiliated Hospital, Guangzhou University of Chinese Medicine, Shenzhen, China
| | - Wenjing Wang
- Department of Nephrology, Shenzhen Affiliated Hospital, Guangzhou University of Chinese Medicine, Shenzhen, China
| | - Pengxun Han
- Department of Nephrology, Shenzhen Affiliated Hospital, Guangzhou University of Chinese Medicine, Shenzhen, China
| | - Mumin Shao
- Department of Pathology, Shenzhen Affiliated Hospital, Guangzhou University of Chinese Medicine, Shenzhen, China
| | - Gaofeng Song
- Department of Nephrology, Shenzhen Affiliated Hospital, Guangzhou University of Chinese Medicine, Shenzhen, China
| | - Heng Du
- Department of Biological Sciences, the University of Texas at Dallas, Richardson, Texas, USA
| | - Tiegang Yi
- Department of Nephrology, Shenzhen Affiliated Hospital, Guangzhou University of Chinese Medicine, Shenzhen, China
| | - Shunmin Li
- Department of Nephrology, Shenzhen Affiliated Hospital, Guangzhou University of Chinese Medicine, Shenzhen, China
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Brenneman J, Hill J, Pullen S. Emerging therapeutics for the treatment of diabetic nephropathy. Bioorg Med Chem Lett 2016; 26:4394-4402. [PMID: 27520943 DOI: 10.1016/j.bmcl.2016.07.079] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 07/27/2016] [Accepted: 07/29/2016] [Indexed: 02/06/2023]
Abstract
Diabetic nephropathy (DN) is the most common pathology contributing to the development of chronic kidney disease (CKD). DN caused by hypertension and unmitigated inflammation in diabetics, renders the kidneys unable to perform normally, and leads to renal fibrosis and organ failure. The increasing global prevalence of DN has been directly attributed to rising incidences of Type II diabetes, and is now the largest non-communicable cause of death worldwide. Despite the high morbidity, successful new treatments for DN are lacking. This review seeks to provide new insight on emerging clinical candidates under investigation for the treatment of DN.
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Affiliation(s)
- Jehrod Brenneman
- Small Molecule Discovery Research, Boehringer-Ingelheim Pharmaceuticals Inc., 900 Ridgebury Rd., Ridgefield, CT 06877, USA.
| | - Jon Hill
- Research Networking, Boehringer-Ingelheim Pharmaceuticals Inc., 900 Ridgebury Rd., Ridgefield, CT 06877, USA
| | - Steve Pullen
- Cardiometabolic Disease Research, Boehringer-Ingelheim Pharmaceuticals Inc., 900 Ridgebury Rd., Ridgefield, CT 06877, USA
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Katsoulieris EN, Drossopoulou GI, Kotsopoulou ES, Vlahakos DV, Lianos EA, Tsilibary EC. High Glucose Impairs Insulin Signaling in the Glomerulus: An In Vitro and Ex Vivo Approach. PLoS One 2016; 11:e0158873. [PMID: 27434075 PMCID: PMC4951020 DOI: 10.1371/journal.pone.0158873] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 06/23/2016] [Indexed: 01/14/2023] Open
Abstract
Objective Chronic hyperglycaemia, as seen in type II diabetes, results in both morphological and functional impairments of podocytes in the kidney. We investigated the effects of high glucose (HG) on the insulin signaling pathway, focusing on cell survival and apoptotic markers, in immortalized human glomerular cells (HGEC; podocytes) and isolated glomeruli from healthy rats. Methods and Findings HGEC and isolated glomeruli were cultured for various time intervals under HG concentrations in the presence or absence of insulin. Our findings indicated that exposure of HGEC to HG led to downregulation of all insulin signaling markers tested (IR, p-IR, IRS-1, p-Akt, p-Fox01,03), as well as to increased sensitivity to apoptosis (as seen by increased PARP cleavage, Casp3 activation and DNA fragmentation). Short insulin pulse caused upregulation of insulin signaling markers (IR, p-IR, p-Akt, p-Fox01,03) in a greater extent in normoglycaemic cells compared to hyperglycaemic cells and for the case of p-Akt, in a PI3K-dependent manner. IRS-1 phosphorylation of HG-treated podocytes was negatively regulated, favoring serine versus tyrosine residues. Prolonged insulin treatment caused a significant decrease of IR levels, while alterations in glucose concentrations for various time intervals demonstrated changes of IR, p-IR and p-Akt levels, suggesting that the IR signaling pathway is regulated by glucose levels. Finally, HG exerted similar effects in isolated glomeruli. Conclusions These results suggest that HG compromises the insulin signaling pathway in the glomerulus, promoting a proapoptotic environment, with a possible critical step for this malfunction lying at the level of IRS-1 phosphorylation; thus we herein demonstrate glomerular insulin signaling as another target for investigation for the prevention and/ or treatment of diabetic nephropathy.
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Affiliation(s)
- Elias N. Katsoulieris
- Institute of Biosciences and Applications, National Center for Scientific Research ‘Demokritos’, Athens, Greece
| | - Garyfalia I. Drossopoulou
- Institute of Biosciences and Applications, National Center for Scientific Research ‘Demokritos’, Athens, Greece
- * E-mail: (GID); (ECT)
| | - Eleni S. Kotsopoulou
- Institute of Biosciences and Applications, National Center for Scientific Research ‘Demokritos’, Athens, Greece
| | - Dimitrios V. Vlahakos
- 2nd Department of Propaedeutic Medicine, Attikon University Hospital, Athens, Greece
| | - Elias A. Lianos
- Department of Pathology, National and Kapodistrian University of Athens, Medical School, Athens, Greece
| | - Effie C. Tsilibary
- Institute of Biosciences and Applications, National Center for Scientific Research ‘Demokritos’, Athens, Greece
- * E-mail: (GID); (ECT)
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Zhuang A, Forbes JM. Diabetic kidney disease: a role for advanced glycation end-product receptor 1 (AGE-R1)? Glycoconj J 2016; 33:645-52. [PMID: 27270766 DOI: 10.1007/s10719-016-9693-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 05/26/2016] [Accepted: 05/27/2016] [Indexed: 01/07/2023]
Abstract
Diabetic patients are postulated to be in a perpetual state of oxidative stress and inflammation at sites where chronic complications occur. The accumulation of AGEs derived from both endogenous and exogenous sources (such as the diet) have been implicated in the development and progression of diabetic complications, particularly nephropathy. There has been some interest in investigating the potential for reducing the AGE burden in chronic disease, through the action of AGE "clearance" receptors, such as the advanced glycation end-product receptor 1 (AGE-R1). Reducing the burden of AGEs has been linked to attenuation of inflammation, slower progression of diabetic complications (in particular vascular and renal complications) and has been shown to extend lifespan. To date, however, there have been no direct investigations into whether AGE-R1 has any role in modulating normal kidney function, or specifically during the development and progression of diabetes. This mini-review will focus on the recent advances in knowledge around the mechanistic function of AGE-R1 and the implications of this for the pathogenesis of diabetic kidney disease.
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Affiliation(s)
- Aowen Zhuang
- Glycation and Diabetes Group, Mater Research Institute, Translational Research Institute, The University of Queensland, South Brisbane, Queensland, Australia
| | - Josephine M Forbes
- Glycation and Diabetes Group, Mater Research Institute, Translational Research Institute, The University of Queensland, South Brisbane, Queensland, Australia. .,Mater Clinical School, The University of Queensland, South Brisbane, Queensland, Australia.
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Audzeyenka I, Rogacka D, Piwkowska A, Rychlowski M, Bierla JB, Czarnowska E, Angielski S, Jankowski M. Reactive oxygen species are involved in insulin-dependent regulation of autophagy in primary rat podocytes. Int J Biochem Cell Biol 2016; 75:23-33. [DOI: 10.1016/j.biocel.2016.03.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 03/10/2016] [Accepted: 03/25/2016] [Indexed: 01/09/2023]
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Naik AS, Afshinnia F, Cibrik D, Hodgin JB, Wu F, Zhang M, Kikuchi M, Wickman L, Samaniego M, Bitzer M, Wiggins JE, Ojo A, Li Y, Wiggins RC. Quantitative podocyte parameters predict human native kidney and allograft half-lives. JCI Insight 2016; 1:86943. [PMID: 27280173 PMCID: PMC4894348 DOI: 10.1172/jci.insight.86943] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 04/19/2016] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Kidney function decreases with age. A potential mechanistic explanation for kidney and allograft half-life has evolved through the realization that linear reduction in glomerular podocyte density could drive progressive glomerulosclerosis to impact both native kidney and allograft half-lives. METHODS Predictions from podometrics (quantitation of podocyte parameters) were tested using independent pathologic, functional, and outcome data for native kidneys and allografts derived from published reports and large registries. RESULTS With age, native kidneys exponentially develop glomerulosclerosis, reduced renal function, and end-stage kidney disease, projecting a finite average kidney life span. The slope of allograft failure rate versus age parallels that of reduction in podocyte density versus age. Quantitative modeling projects allograft half-life at any donor age, and rate of podocyte detachment parallels the observed allograft loss rate. CONCLUSION Native kidneys are designed to have a limited average life span of about 100-140 years. Allografts undergo an accelerated aging-like process that accounts for their unexpectedly short half-life (about 15 years), the observation that older donor age is associated with shorter allograft half-life, and the fact that long-term allograft survival has not substantially improved. Podometrics provides potential readouts for these processes, thereby offering new approaches for monitoring and intervention. FUNDING National Institutes of Health.
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Affiliation(s)
| | | | | | | | - Fan Wu
- School of Public Health, and
| | | | | | - Larysa Wickman
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan, USA
| | | | | | | | | | - Yi Li
- School of Public Health, and
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Wickman L, Hodgin JB, Wang SQ, Afshinnia F, Kershaw D, Wiggins RC. Podocyte Depletion in Thin GBM and Alport Syndrome. PLoS One 2016; 11:e0155255. [PMID: 27192434 PMCID: PMC4871445 DOI: 10.1371/journal.pone.0155255] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 04/26/2016] [Indexed: 01/15/2023] Open
Abstract
The proximate genetic cause of both Thin GBM and Alport Syndrome (AS) is abnormal α3, 4 and 5 collagen IV chains resulting in abnormal glomerular basement membrane (GBM) structure/function. We previously reported that podocyte detachment rate measured in urine is increased in AS, suggesting that podocyte depletion could play a role in causing progressive loss of kidney function. To test this hypothesis podometric parameters were measured in 26 kidney biopsies from 21 patients aged 2–17 years with a clinic-pathologic diagnosis including both classic Alport Syndrome with thin and thick GBM segments and lamellated lamina densa [n = 15] and Thin GBM cases [n = 6]. Protocol biopsies from deceased donor kidneys were used as age-matched controls. Podocyte depletion was present in AS biopsies prior to detectable histologic abnormalities. No abnormality was detected by light microscopy at <30% podocyte depletion, minor pathologic changes (mesangial expansion and adhesions to Bowman’s capsule) were present at 30–50% podocyte depletion, and FSGS was progressively present above 50% podocyte depletion. eGFR did not change measurably until >70% podocyte depletion. Low level proteinuria was an early event at about 25% podocyte depletion and increased in proportion to podocyte depletion. These quantitative data parallel those from model systems where podocyte depletion is the causative event. This result supports a hypothesis that in AS podocyte adherence to the GBM is defective resulting in accelerated podocyte detachment causing progressive podocyte depletion leading to FSGS-like pathologic changes and eventual End Stage Kidney Disease. Early intervention to reduce podocyte depletion is projected to prolong kidney survival in AS.
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Affiliation(s)
- Larysa Wickman
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Jeffrey B. Hodgin
- Department of Pathology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Su Q. Wang
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Farsad Afshinnia
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - David Kershaw
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Roger C. Wiggins
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
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Kikuchi M, Wickman L, Hodgin JB, Wiggins RC. Podometrics as a Potential Clinical Tool for Glomerular Disease Management. Semin Nephrol 2016. [PMID: 26215862 DOI: 10.1016/j.semnephrol.2015.04.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Chronic kidney disease culminating in end-stage kidney disease is a major public health problem costing in excess of $40 billion per year with high morbidity and mortality. Current tools for glomerular disease monitoring lack precision and contribute to poor outcome. The podocyte depletion hypothesis describes the major mechanisms underlying the progression of glomerular diseases, which are responsible for more than 80% of cases of end-stage kidney disease. The question arises of whether this new knowledge can be used to improve outcomes and reduce costs. Podocytes have unique characteristics that make them an attractive monitoring tool. Methodologies for estimating podocyte number, size, density, glomerular volume and other parameters in routine kidney biopsies, and the rate of podocyte detachment from glomeruli into urine (podometrics) now have been developed and validated. They potentially fill important gaps in the glomerular disease monitoring toolbox. The application of these tools to glomerular disease groups shows good correlation with outcome, although data validating their use for individual decision making is not yet available. Given the urgency of the clinical problem, we argue that the time has come to focus on testing these tools for application to individualized clinical decision making toward more effective progression prevention.
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Affiliation(s)
- Masao Kikuchi
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI
| | - Larysa Wickman
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI
| | | | - Roger C Wiggins
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI.
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Zou R, Wang SX, Liu G, Yu F, Chen M, Zhao MH. Podocyte Detachment Is Associated with Renal Prognosis in ANCA-Associated Glomerulonephritis: A Retrospective Cohort Study. Medicine (Baltimore) 2016; 95:e3294. [PMID: 27082569 PMCID: PMC4839813 DOI: 10.1097/md.0000000000003294] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
The prognosis of antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis (ANCA-GN) is unfavorable despite immunosuppressive therapy. It has been suggested that the loss of podocytes is a hallmark of progressive kidney disease. However, it is unclear about podocyte injuries and their predictive values on the prognosis in ANCA-GN. Therefore, the current study aimed to investigate the podocyte injury in renal histopathology and its association with renal prognosis of patients with ANCA-GN. A total of 170 patients with ANCA-GN were recruited in this study. Morphometric investigation of podocytes by electron microscopy including foot process width (FPW), podocyte density per glomerulus (Nv), and glomerular basement membrane (GBM) width were measured and calculated in ANCA-GN patients. Cox regression analysis was used to analyze the association between podocyte injuries and prognosis of patients with ANCA-GN. Foot processes broadening, podocyte detachment, and GBM thickening could be observed in electron micrographs in the specimens of 158/170 (92.9%), 142/170 (83.5%), and 150/170 (88.2%) patients, respectively. Compared with normal controls, FPW and GBM width in ANCA-GN patients was significantly higher (1269.39 ± 680.19 vs 585.81 ± 77.16, P = 0.004; 668.23 ± 208.73 vs 354.23 ± 52.70, P = 0.000, respectively), while the podocyte density was significantly lower (55.90 ± 36.32 vs 255.23 ± 47.29, P = 0.000). The podocyte density was independently associated with the recovery of renal function in logistic regression analysis (OR, 1.083; 95% CI, 1.025-1.440; P = 0.005). Furthermore, multivariate analysis revealed that podocyte density was an independent predictor of end-stage renal disease (ESRD) (model A: HR, 0.950; 95% CI, 0.919-1.982; P = 0.002; model B: HR, 0.953; 95% CI, 0.922-0.985; P = 0.004). Podocyte structural damage and detachment occurred frequently in patients with ANCA-GN. Moreover, podocyte detachment was an independent predictor of renal outcomes.
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Affiliation(s)
- Rong Zou
- From the Renal Division, Department of Medicine, Peking University, First Hospital; Peking University Institute of Nephrology; Key Laboratory of Renal Disease, Ministry of Health of China; Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education; Peking-Tsinghua Center for Life Sciences (RZ, S-XW, GL, FY, MC, M-HZ), Beijing; and Renal Division, Department of Medicine, Wuhan Integrated TCM and Western Medicine Hospital (RZ), Wuhan, China
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Xu L, Zhang P, Guan H, Huang Z, He X, Wan X, Xiao H, Li Y. Vitamin D and its receptor regulate lipopolysaccharide-induced transforming growth factor-β, angiotensinogen expression and podocytes apoptosis through the nuclear factor-κB pathway. J Diabetes Investig 2016; 7:680-8. [PMID: 27180929 PMCID: PMC5009129 DOI: 10.1111/jdi.12505] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 01/13/2016] [Accepted: 02/20/2016] [Indexed: 12/01/2022] Open
Abstract
AIMS/INTRODUCTION To investigate the effects of vitamin D and its receptor on cytokines expression and podocytes apoptosis. MATERIALS AND METHODS Cultured mouse podocytes were pre-incubated with vitamin D or transiently transfected with small interfering ribonucleic acid (RNA) to knock down the vitamin D receptor. Lipopolysaccharide was used to mimic the inflammation status of diabetes. RESULTS In a lipopolysaccharide-induced state, expressions of transforming growth factor-β, angiotensinogen and vascular endothelial growth factor were similarly increased. Transforming growth factor-β and angiotensinogen levels originally elevated by lipopolysaccharide challenge were distinctly reduced after pre-incubation with vitamin D. Whereas after vitamin D receptor small interfering (si)RNA transfection, the aforementioned cytokines had opposite changes as expected. However, neither vitamin D pretreatment nor vitamin D receptor siRNA transfection influenced the previously increased vascular endothelial growth factor expression at messenger RNA or protein levels. When pretreated with vitamin D, decreases were observed for phosphorylated inhibitor-κB and the inhibitor kinase proteins. After siRNA transfection, those proteins levels were further elevated. The originally increased transforming growth factor-β and angiotensinogen levels as a result of lipopolysaccharide stimulation were reduced at both the messenger RNA and protein levels after the specific inhibition of the nuclear factor-κB pathway with pyrrolidine dithiocarbamate. The apoptosis rate of podocytes was decreased in a parallel manner after vitamin D pre-incubation, and increased after siRNA transfection, which was also suppressed by pyrrolidine dithiocarbamate. CONCLUSIONS Vitamin D and its receptor might be involved in the progression of diabetic nephropathy by regulating transforming growth factor-β, angiotensinogen expression and apoptosis of podocytes. The processes are mediated through the signaling of nuclear factor-κB pathway.
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Affiliation(s)
- Lijuan Xu
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Pengyuan Zhang
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Hongyu Guan
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Zhimin Huang
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Xiaoying He
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Xuesi Wan
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Haipeng Xiao
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Yanbing Li
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
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Silva AP, Mendes F, Fragoso A, Jeronimo T, Pimentel A, Gundlach K, Büchel J, Santos N, Neves PL. Altered serum levels of FGF-23 and magnesium are independent risk factors for an increased albumin-to-creatinine ratio in type 2 diabetics with chronic kidney disease. J Diabetes Complications 2016; 30:275-80. [PMID: 26750742 DOI: 10.1016/j.jdiacomp.2015.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 11/03/2015] [Accepted: 11/04/2015] [Indexed: 12/12/2022]
Abstract
AIMS To investigate the role of FGF-23 and magnesium in relation to the albumin-to-creatinine ratio in type 2 diabetics with chronic kidney disease (CKD) stages 2-4. METHODS In a cross-sectional study we included all eligible type 2 diabetic patients with CKD stages 2-4, followed in our outpatient Diabetic Kidney clinic. We used descriptive statistics, the Student'st-test, ANOVA and the chi-square tests. Our population was divided according to the UACR (G1 30-300 mg/g and G2≥300 mg/g), and compared these groups regarding several biological and laboratorial parameters. We employed a multiple regression model to identify risk factors of increased UACR. RESULTS The patients in G2 displayed a lower eGFR (p=0.0001) and, had lower levels of magnesium (p=0.004) as well as higher levels of FGF-23 (p=0.043) compared to patients in G1. FGF-23 (β=0.562, P=0.0001) and the magnesium (β=- 8.916, p=0.0001) were associated with increased UACR. CONCLUSIONS A dysregulation of mineral metabolism, reflected by altered levels of magnesium and FGF-23, correlates with an increased UACR in type 2 diabetic patients with CKD stages 2-4.
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Affiliation(s)
- Ana Paula Silva
- Nephrology, Centro Hospitalar do Algarve, Faro, Portugal; Department of Biomedical Sciences and Medicine, University of Algarve, Faro, Portugal.
| | - Filipa Mendes
- Nephrology, Centro Hospitalar do Algarve, Faro, Portugal
| | - André Fragoso
- Nephrology, Centro Hospitalar do Algarve, Faro, Portugal
| | | | - Ana Pimentel
- Nephrology, Centro Hospitalar do Algarve, Faro, Portugal
| | - Kristina Gundlach
- Fresenius Medical Care Deutschland GmbH, Bad Homburg vor der Höhe, Germany
| | - Janine Büchel
- Fresenius Medical Care Deutschland GmbH, Bad Homburg vor der Höhe, Germany
| | - Nélio Santos
- Pathology Clinic, Centro Hospitalar do Algarve, Faro, Portugal
| | - Pedro Leão Neves
- Nephrology, Centro Hospitalar do Algarve, Faro, Portugal; Department of Biomedical Sciences and Medicine, University of Algarve, Faro, Portugal
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Puelles VG, Cullen-McEwen LA, Taylor GE, Li J, Hughson MD, Kerr PG, Hoy WE, Bertram JF. Human podocyte depletion in association with older age and hypertension. Am J Physiol Renal Physiol 2016; 310:F656-F668. [PMID: 26792066 DOI: 10.1152/ajprenal.00497.2015] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 01/12/2016] [Indexed: 12/27/2022] Open
Abstract
Podocyte depletion plays a major role in the development and progression of glomerulosclerosis. Many kidney diseases are more common in older age and often coexist with hypertension. We hypothesized that podocyte depletion develops in association with older age and is exacerbated by hypertension. Kidneys from 19 adult Caucasian American males without overt renal disease were collected at autopsy in Mississippi. Demographic data were obtained from medical and autopsy records. Subjects were categorized by age and hypertension as potential independent and additive contributors to podocyte depletion. Design-based stereology was used to estimate individual glomerular volume and total podocyte number per glomerulus, which allowed the calculation of podocyte density (number per volume). Podocyte depletion was defined as a reduction in podocyte number (absolute depletion) or podocyte density (relative depletion). The cortical location of glomeruli (outer or inner cortex) and presence of parietal podocytes were also recorded. Older age was an independent contributor to both absolute and relative podocyte depletion, featuring glomerular hypertrophy, podocyte loss, and thus reduced podocyte density. Hypertension was an independent contributor to relative podocyte depletion by exacerbating glomerular hypertrophy, mostly in glomeruli from the inner cortex. However, hypertension was not associated with podocyte loss. Absolute and relative podocyte depletion were exacerbated by the combination of older age and hypertension. The proportion of glomeruli with parietal podocytes increased with age but not with hypertension alone. These findings demonstrate that older age and hypertension are independent and additive contributors to podocyte depletion in white American men without kidney disease.
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Affiliation(s)
- Victor G Puelles
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria, Australia;
| | - Luise A Cullen-McEwen
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria, Australia
| | - Georgina E Taylor
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria, Australia
| | - Jinhua Li
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria, Australia
| | - Michael D Hughson
- Department of Pathology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Peter G Kerr
- Department of Nephrology, Monash Medical Centre, and Department of Medicine, Monash University, Melbourne, Victoria, Australia; and
| | - Wendy E Hoy
- Centre for Chronic Disease, The University of Queensland, Brisbane, Queensland, Australia
| | - John F Bertram
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria, Australia
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Abstract
Podocyte hypertrophy and apoptosis are two hallmarks of diabetic glomeruli, but the sequence in which these processes occur remains a matter of debate. Here we investigated the effects of inhibiting hypertrophy on apoptosis, and vice versa, in both podocytes and glomeruli, under diabetic conditions. Hypertrophy and apoptosis were inhibited using an epidermal growth factor receptor inhibitor (PKI 166) and a pan-caspase inhibitor (zAsp-DCB), respectively. We observed significant increases in the protein expression of p27, p21, phospho-eukaryotic elongation factor 4E-binding protein 1, and phospho-p70 S6 ribosomal protein kinase, in both cultured podocytes exposed to high-glucose (HG) medium, and streptozotocin-induced diabetes mellitus (DM) rat glomeruli. These increases were significantly inhibited by PKI 166, but not by zAsp-DCB. In addition, the amount of protein per cell, the relative cell size, and the glomerular volume were all significantly increased under diabetic conditions, and these changes were also blocked by treatment with PKI 166, but not zAsp-DCB. Increased protein expression of cleaved caspase-3 and cleaved poly (ADP-ribose) polymerase, together with increased Bax/Bcl-2 ratios, were also observed in HG-stimulated podocytes and DM glomeruli. Treatment with either zAsp-DCB or PKI 166 resulted in a significant attenuation of these effects. Both PKI 166 and zAsp-DCB also inhibited the increase in number of apoptotic cells, as assessed by Hoechst 33342 staining and TUNEL assay. Under diabetic conditions, inhibition of podocyte hypertrophy results in attenuated apoptosis, whereas blocking apoptosis has no effect on podocyte hypertrophy, suggesting that podocyte hypertrophy precedes apoptosis.
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Sawada K, Toyoda M, Kaneyama N, Shiraiwa S, Moriya H, Miyatake H, Tanaka E, Yamamoto N, Miyauchi M, Kimura M, Wada T, Fukagawa M. Upregulation of α3β1-Integrin in Podocytes in Early-Stage Diabetic Nephropathy. J Diabetes Res 2016; 2016:9265074. [PMID: 27340677 PMCID: PMC4908236 DOI: 10.1155/2016/9265074] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 05/05/2016] [Indexed: 01/15/2023] Open
Abstract
Background. Podocyte injury plays an important role in the onset and progression of diabetic nephropathy (DN). Downregulation of α3β1-integrin expression in podocytes is thought to be associated with podocyte detachment from the glomerular basement membrane, although the mechanisms remain obscure. To determine the mechanism of podocyte detachment, we analyzed the expression levels of α3β1-integrin in podocytes in early and advanced stages of DN. Methods. Surgical specimens from DN patients were examined by in situ hybridization, and the expression levels of α3- and β1-integrin subunits in glomeruli of early (n = 6) and advanced (n = 8) stages were compared with those of normal glomeruli (n = 5). Heat-sensitive mouse podocytes (HSMP) were cultured with TGF-β1 to reproduce the microenvironment of glomeruli of DN, and the expression levels of integrin subunits and the properties of migration and attachment were examined. Results. Podocytes of early-stage DN showed upregulation of α3- and β1-integrin expression while those of advanced stage showed downregulation. Real-time PCR indicated a tendency for upregulation of α3- and β1-integrin in HSMP cultured with TGF-β1. TGF-β1-stimulated HSMP also showed enhanced in vitro migration and attachment on collagen substrate. Conclusions. The results suggested that podocyte detachment during early stage of DN is mediated through upregulation of α3β1-integrin.
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Affiliation(s)
- Kaichiro Sawada
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
| | - Masao Toyoda
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
- *Masao Toyoda:
| | - Noriko Kaneyama
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
| | - Sawako Shiraiwa
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
| | - Hitomi Moriya
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
| | - Han Miyatake
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
| | - Eitaro Tanaka
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
| | - Naoyuki Yamamoto
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
| | - Masaaki Miyauchi
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
| | - Moritsugu Kimura
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
| | - Takehiko Wada
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
| | - Masafumi Fukagawa
- Division of Nephrology, Endocrinology and Metabolism, Department of Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan
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Semiautomated quantitative image analysis of glomerular immunohistochemistry markers desmin, vimentin, podocin, synaptopodin and WT-1 in acute and chronic rat kidney disease models. Histochem Cell Biol 2015; 145:315-26. [DOI: 10.1007/s00418-015-1391-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/27/2015] [Indexed: 12/24/2022]
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Bhatti AB, Usman M. Drug Targets for Oxidative Podocyte Injury in Diabetic Nephropathy. Cureus 2015; 7:e393. [PMID: 26798569 PMCID: PMC4699926 DOI: 10.7759/cureus.393] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Accepted: 11/30/2015] [Indexed: 12/19/2022] Open
Abstract
Diabetic nephropathy (DN) is one the most prevalent chronic complications of diabetes mellitus that affects as much as one-third of diabetic patients irrespective of the type of diabetes. Hyperglycemia is the key trigger for DN that initiates a number of microscopic and ultramicroscopic changes in kidney architecture. Microscopic changes include thickening of the glomerular basement membrane (GBM), tubular basement membrane (TBM), mesangial proliferation, arteriosclerosis, and glomerulotubular junction abnormalities (GTJA). Among the ultramicroscopic changes, effacement of podocytes and decrease in their density seem to be the centerpiece of DN pathogenesis. These changes in kidney architecture then produce functional deficits, such as microalbuminuria and decreased glomerular filtration rate (GFR). Among several mechanisms involved in inflicting damage to podocytes, injuries sustained by increased oxidative stress turns out to be the most important mechanism. Different variables that are included in increased production of reactive oxygen species (ROS) include a hyperglycemia-induced reduction in glutathione (GSH), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation via hyperglycemia, advanced glycation end products (AGEs), protein kinase C (PKC), and renin-angiotensin-aldosterone system (RAAS). Unfortunately, control of podocyte injury hasn't received much attention as a treatment approach for DN. Therefore, this review article is mainly concerned with the exploration of various treatment options that might help in decreasing the podocyte injury, mainly by reducing the level of NADPH oxidase-mediated generation of ROS. This article concludes with a view that certain NADPH oxidase inhibitors, RAAS inhibitors, statins, antidiabetic drugs, and antioxidant vitamins might be useful in decreasing podocyte injury and resultant structural and functional kidney impairments in DN.
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Affiliation(s)
- Adnan Bashir Bhatti
- Department of Medicine, Capital Development Authority Hospital, Islamabad, Pakistan
| | - Muhammad Usman
- Department of Medicine, Jinnah Hospital Lahore (JHL)/Allama Iqbal Medical College (AIMC), Lahore, Pakistan
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81
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IRS2 and PTEN are key molecules in controlling insulin sensitivity in podocytes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:3224-34. [PMID: 26384875 DOI: 10.1016/j.bbamcr.2015.09.020] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 09/01/2015] [Accepted: 09/14/2015] [Indexed: 01/03/2023]
Abstract
Insulin signaling to the glomerular podocyte is important for normal kidney function and is implicated in the pathogenesis of diabetic nephropathy (DN). This study determined the role of the insulin receptor substrate 2 (IRS2) in this system. Conditionally immortalized murine podocytes were generated from wild-type (WT) and insulin receptor substrate 2-deficient mice (Irs2(-/-)). Insulin signaling, glucose transport, cellular motility and cytoskeleton rearrangement were then analyzed. Within the glomerulus IRS2 is enriched in the podocyte and is preferentially phosphorylated by insulin in comparison to IRS1. Irs2(-/-) podocytes are significantly insulin resistant in respect to AKT signaling, insulin-stimulated GLUT4-mediated glucose uptake, filamentous actin (F-actin) cytoskeleton remodeling and cell motility. Mechanistically, we discovered that Irs2 deficiency causes insulin resistance through up-regulation of the phosphatase and tensin homolog (PTEN). Importantly, suppressing PTEN in Irs2(-/-) podocytes rescued insulin sensitivity. In conclusion, this study has identified for the first time IRS2 as a critical molecule for sensitizing the podocyte to insulin actions through its ability to modulate PTEN expression. This finding reveals two potential molecular targets in the podocyte for modulating insulin sensitivity and treating DN.
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82
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Kahvecioglu S, Guclu M, Ustundag Y, Gul CB, Dogan I, Dagel T, Esen B, Akturk Esen S, Celik H, Esen I. Evaluation of serum Spondin 2 levels in the different stages of Type 2 diabetic nephropathy. Nephrology (Carlton) 2015; 20:721-726. [DOI: 10.1111/nep.12507] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/09/2015] [Indexed: 12/17/2022]
Affiliation(s)
- Serdar Kahvecioglu
- Department of Nephrology; Bursa Sevket Yilmaz Training and Research Hospital; Bursa Turkey
| | - Metin Guclu
- Department of Endocrinology; Bursa Sevket Yilmaz Training and Research Hospital; Bursa Turkey
| | - Yasemin Ustundag
- Department of Biochemistry; Bursa Sevket Yilmaz Training and Research Hospital; Bursa Turkey
| | - Cuma Bulent Gul
- Department of Nephrology; Bursa Sevket Yilmaz Training and Research Hospital; Bursa Turkey
| | - Ibrahim Dogan
- Department of Nephrology; Bursa Sevket Yilmaz Training and Research Hospital; Bursa Turkey
| | - Tuncay Dagel
- Department of Nephrology; Bursa Sevket Yilmaz Training and Research Hospital; Bursa Turkey
| | - Bennur Esen
- Department of Nephrology; Bursa Sevket Yilmaz Training and Research Hospital; Bursa Turkey
| | - Selin Akturk Esen
- Department of Internal Medicine; Bursa Sevket Yilmaz Training and Research Hospital; Bursa Turkey
| | - Huseyin Celik
- Department of Nephrology; Acibadem Hospital; Bursa Turkey
| | - Irfan Esen
- Department of Internal Medicine; Bursa Sevket Yilmaz Training and Research Hospital; Bursa Turkey
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83
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Guo F, Zhang Y, Wang Q, Ren L, Zhou Y, Ma X, Wu L, Qin G. Effects of FoxO1 on podocyte injury in diabetic rats. Biochem Biophys Res Commun 2015; 466:260-6. [PMID: 26361145 DOI: 10.1016/j.bbrc.2015.09.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Revised: 08/03/2015] [Accepted: 09/05/2015] [Indexed: 10/23/2022]
Abstract
OBJECTIVE This study was designed to investigate the protective effect of forkhead transcription factor O1 (FoxO1) on podocyte injury in rats with diabetic nephropathy. METHODS Streptozotocin-induced diabetic rats were served as DM group, while DM rats transfected with blank lentiviral vectors (LV-pSC-GFP) or lentiviral vectors carrying constitutively active FoxO1 (LV-CA-FoxO1) were served as LV-NC group or LV-CA group, respectively. The control group (NG) consisted of uninduced rats that received an injection of diluent buffer. At 2, 4, and 8 weeks after transfection, the levels of urine albumin, blood glucose, blood urea nitrogen, serum creatinine and urine podocalyxin were measured. Real-time PCR and western blotting were performed to measure mRNA and protein levels of FoxO1, podocalyxin, nephrin, and desmin in renal cortex. In addition, light and electron microscopy were used to detect structural changes in the glomerulus and podocytes. RESULTS Compared with the rats in LV-NC and DM groups, LV-CA rats showed a significant increase in FoxO1 mRNA and protein levels and a distinct decrease in urine albumin, blood urea nitrogen, and serum creatinine (except at the two-week time point) levels (p < 0.05). Podocalyxin and nephrin mRNA and protein levels increased (p < 0.05), whereas desmin mRNA and protein levels decreased (p < 0.05). Pathological changes in glomerulus were also ameliorated in LV-CA group. CONCLUSIONS Upregulating expression of FoxO1 by transduction with recombinant lentivirus ameliorates podocyte injury in diabetic rats.
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Affiliation(s)
- Feng Guo
- Department of Endocrinology and Metabolism, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China; Institute of Clinical Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Yuanyuan Zhang
- Department of Endocrinology and Metabolism, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China; Institute of Clinical Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Qingzhu Wang
- Department of Endocrinology and Metabolism, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China; Institute of Clinical Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Lei Ren
- Department of Endocrinology and Metabolism, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China; Institute of Clinical Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Yingni Zhou
- Department of Endocrinology and Metabolism, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China; Institute of Clinical Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Xiaojun Ma
- Department of Endocrinology and Metabolism, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Lina Wu
- Department of Endocrinology and Metabolism, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China; Institute of Clinical Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Guijun Qin
- Department of Endocrinology and Metabolism, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China.
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Effect of Tongxinluo on Nephrin Expression via Inhibition of Notch1/Snail Pathway in Diabetic Rats. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015; 2015:424193. [PMID: 26417374 PMCID: PMC4568378 DOI: 10.1155/2015/424193] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 08/12/2015] [Accepted: 08/12/2015] [Indexed: 11/17/2022]
Abstract
Podocyte injury is an important mechanism of diabetic nephropathy (DN). Accumulating evidence suggests that nephrin expression is decreased in podocyte in DN. Moreover, it has been demonstrated that tongxinluo (TXL) can ameliorate renal structure disruption and dysfunction in DN. However, the effect of TXL on podocyte injury in DN and its molecular mechanism is unclear. In order to explore the effect of TXL on podocyte injury and its molecular mechanism in DN, our in vivo and in vitro studies were performed. Our results showed that TXL increased nephrin expression in diabetic rats and in high glucose cultured podocyte. Meanwhile, TXL decreased ICN1 (the intracellular domain of notch), HES1, and snail expression in podocyte in vivo and in vitro. More importantly, we found that TXL protected podocyte from injury in DN. The results demonstrated that TXL inhibited the activation of notch1/snail pathway and increased nephrin expression, which may be a mechanism of protecting effect on podocyte injury in DN.
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85
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Efficacy of urinary N-acetyl-β-D-glucosaminidase to evaluate early renal tubular damage as a consequence of type 2 diabetes mellitus: a cross-sectional study. Int J Diabetes Dev Ctries 2015. [DOI: 10.1007/s13410-015-0404-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Hodgin JB, Bitzer M, Wickman L, Afshinnia F, Wang SQ, O'Connor C, Yang Y, Meadowbrooke C, Chowdhury M, Kikuchi M, Wiggins JE, Wiggins RC. Glomerular Aging and Focal Global Glomerulosclerosis: A Podometric Perspective. J Am Soc Nephrol 2015; 26:3162-78. [PMID: 26038526 DOI: 10.1681/asn.2014080752] [Citation(s) in RCA: 164] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 02/08/2015] [Indexed: 11/03/2022] Open
Abstract
Kidney aging is associated with an increasing proportion of globally scarred glomeruli, decreasing renal function, and exponentially increasing ESRD prevalence. In model systems, podocyte depletion causes glomerulosclerosis, suggesting age-associated glomerulosclerosis could be caused by a similar mechanism. We measured podocyte number, size, density, and glomerular volume in 89 normal kidney samples from living and deceased kidney donors and normal poles of nephrectomies. Podocyte nuclear density decreased with age due to a combination of decreased podocyte number per glomerulus and increased glomerular volume. Compensatory podocyte cell hypertrophy prevented a change in the proportion of tuft volume occupied by podocytes. Young kidneys had high podocyte reserve (podocyte density >300 per 10(6) µm(3)), but by 70-80 years of age, average podocyte nuclear density decreased to, <100 per 10(6) µm(3), with corresponding podocyte hypertrophy. In older age podocyte detachment rate (urine podocin mRNA-to-creatinine ratio) was higher than at younger ages and podocytes were stressed (increased urine podocin-to-nephrin mRNA ratio). Moreover, in older kidneys, proteinaceous material accumulated in the Bowman space of glomeruli with low podocyte density. In a subset of these glomeruli, mass podocyte detachment events occurred in association with podocytes becoming binucleate (mitotic podocyte catastrophe) and subsequent wrinkling of glomerular capillaries, tuft collapse, and periglomerular fibrosis. In kidneys of young patients with underlying glomerular diseases similar pathologic events were identified in association with focal global glomerulosclerosis. Podocyte density reduction with age may therefore directly lead to focal global glomerulosclerosis, and all progressive glomerular diseases can be considered superimposed accelerators of this underlying process.
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Affiliation(s)
| | | | - Larysa Wickman
- Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan
| | | | | | | | | | - Chrysta Meadowbrooke
- Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan
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Fan Y, Li X, Xiao W, Fu J, Harris RC, Lindenmeyer M, Cohen CD, Guillot N, Baron MH, Wang N, Lee K, He JC, Schlondorff D, Chuang PY. BAMBI elimination enhances alternative TGF-β signaling and glomerular dysfunction in diabetic mice. Diabetes 2015; 64:2220-33. [PMID: 25576053 PMCID: PMC4439561 DOI: 10.2337/db14-1397] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 01/02/2015] [Indexed: 01/11/2023]
Abstract
BMP, activin, membrane-bound inhibitor (BAMBI) acts as a pseudo-receptor for the transforming growth factor (TGF)-β type I receptor family and a negative modulator of TGF-β kinase signaling, and BAMBI(-/-) mice show mild endothelial dysfunction. Because diabetic glomerular disease is associated with TGF-β overexpression and microvascular alterations, we examined the effect of diabetes on glomerular BAMBI mRNA levels. In isolated glomeruli from biopsies of patients with diabetic nephropathy and in glomeruli from mice with type 2 diabetes, BAMBI was downregulated. We then examined the effects of BAMBI deletion on streptozotocin-induced diabetic glomerulopathy in mice. BAMBI(-/-) mice developed more albuminuria, with a widening of foot processes, than BAMBI(+/+) mice, along with increased activation of alternative TGF-β pathways such as extracellular signal-related kinase (ERK)1/2 and Smad1/5 in glomeruli and cortices of BAMBI(-/-) mice. Vegfr2 and Angpt1, genes controlling glomerular endothelial stability, were downmodulated in glomeruli from BAMBI(-/-) mice with diabetes. Incubation of glomeruli from nondiabetic BAMBI(+/+) or BAMBI(-/-) mice with TGF-β resulted in the downregulation of Vegfr2 and Angpt1, effects that were more pronounced in BAMBI(-/-) mice and were prevented by a MEK inhibitor. The downregulation of Vegfr2 in diabetes was localized to glomerular endothelial cells using a histone yellow reporter under the Vegfr2 promoter. Thus, BAMBI modulates the effects of diabetes on glomerular permselectivity in association with altered ERK1/2 and Smad1/5 signaling. Future therapeutic interventions with inhibitors of alternative TGF-β signaling may therefore be of interest in diabetic nephropathy.
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Affiliation(s)
- Ying Fan
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY Department of Nephrology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Xuezhu Li
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Wenzhen Xiao
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Jia Fu
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Ray C Harris
- Vanderbilt University School of Medicine, Nashville, TN
| | - Maja Lindenmeyer
- Division of Nephrology and Institute of Physiology with Center of Integrative Human Physiology, University Hospital and University of Zurich, Zurich, Switzerland
| | - Clemens D Cohen
- Division of Nephrology and Institute of Physiology with Center of Integrative Human Physiology, University Hospital and University of Zurich, Zurich, Switzerland
| | - Nicolas Guillot
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Margaret H Baron
- Tisch Cancer Institute and Department of Medicine, Division of Hematology and Medical Oncology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Niansong Wang
- Department of Nephrology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Kyung Lee
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - John C He
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY Renal Section, James J. Peter Veterans Administration Medical Center, Bronx, NY
| | - Detlef Schlondorff
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Peter Y Chuang
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY
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Harindhanavudhi T, Parks A, Mauer M, Caramori ML. Podocyte structural parameters do not predict progression to diabetic nephropathy in normoalbuminuric type 1 diabetic patients. Am J Nephrol 2015; 41:277-83. [PMID: 26021523 DOI: 10.1159/000381992] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 03/28/2015] [Indexed: 11/19/2022]
Abstract
BACKGROUND Podocyte injury has been implicated in diabetic nephropathy (DN) ranging from normoalbuminuria to proteinuria in both type 1 and type 2 diabetes. METHODS To determine whether podocyte structural parameters predict DN risk in initially normoalbuminuric long-standing type 1 diabetic patients, we performed a nested case-control study in sex and diabetes duration-matched progressors (progression to proteinuria or ESRD, n = 10), non-progressors (normoalbuminuric at follow-up, n = 10), and non-diabetic controls (n = 10). RESULTS HbA1c and diastolic blood pressure were higher in progressors versus non-progressors. Podocyte number per glomerulus, numerical density of podocyte per glomerulus, and foot process width were not different among groups. The glomerular basement membrane width was greater in progressors versus non-progressors or controls, and in non-progressors versus controls. As expected, the mesangial fractional volume was greater in progressors and non-progressors versus controls, with no differences between progressors and non-progressors. CONCLUSION This study does not indicate that podocyte structural changes are preconditions for later DN progression in initially normoalbuminuric type 1 diabetic patients. However, this does not preclude an important role for podocyte injury at a later stage of DN.
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Fukuda A, Sato Y, Iwakiri T, Komatsu H, Kikuchi M, Kitamura K, Wiggins RC, Fujimoto S. Urine podocyte mRNAs mark disease activity in IgA nephropathy. Nephrol Dial Transplant 2015; 30:1140-50. [PMID: 25956757 DOI: 10.1093/ndt/gfv104] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 03/21/2015] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Podocyte depletion is a major mechanism driving glomerulosclerosis. We and others have previously projected from model systems that podocyte-specific mRNAs in the urine pellet might serve as glomerular disease markers. We evaluated IgA nephropathy (IgAN) to test this concept. METHODS From 2009 to 2013, early morning voided urine samples and kidney biopsies from IgAN patients (n = 67) were evaluated in comparison with urine samples from healthy age-matched volunteers (n = 28). Urine podocyte (podocin) mRNA expressed in relation to either urine creatinine concentration or a kidney tubular marker (aquaporin 2) was tested as markers. RESULTS Urine podocyte mRNAs were correlated with the severity of active glomerular lesions (segmental glomerulosclerosis and acute extracapillary proliferation), but not with non-glomerular lesions (tubular atrophy/interstitial fibrosis) or with clinical parameters of kidney injury (serum creatinine and estimated glomerular filtration rate), or with degree of accumulated podocyte loss at the time of biopsy. In contrast, proteinuria correlated with all histological and clinical markers. Glomerular tuft podocyte nuclear density (a measure of cumulative podocyte loss) correlated with tubular atrophy/interstitial fibrosis, estimated-glomerular filtration rate and proteinuria, but not with urine podocyte markers. In a subset of the IgA cohort (n = 19, median follow-up period = 37 months), urine podocyte mRNAs were significantly decreased after treatment, in contrast to proteinuria which was not significantly changed. CONCLUSIONS Urine podocyte mRNAs reflect active glomerular injury at a given point in time, and therefore provide both different and additional clinical information that can complement proteinuria in the IgAN decision-making paradigm.
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Affiliation(s)
- Akihiro Fukuda
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Yuji Sato
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Takashi Iwakiri
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Hiroyuki Komatsu
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Masao Kikuchi
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Kazuo Kitamura
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan
| | - Roger C Wiggins
- Division of Nephrology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Shouichi Fujimoto
- First Department of Internal Medicine, University of Miyazaki, Miyazaki, Japan Department of Hemovascular Medicine and Artificial Organs, University of Miyazaki, Miyazaki, Japan
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90
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Puelles VG, Douglas-Denton RN, Cullen-McEwen LA, Li J, Hughson MD, Hoy WE, Kerr PG, Bertram JF. Podocyte Number in Children and Adults: Associations with Glomerular Size and Numbers of Other Glomerular Resident Cells. J Am Soc Nephrol 2015; 26:2277-88. [PMID: 25568174 DOI: 10.1681/asn.2014070641] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 11/02/2014] [Indexed: 11/03/2022] Open
Abstract
Increases in glomerular size occur with normal body growth and in many pathologic conditions. In this study, we determined associations between glomerular size and numbers of glomerular resident cells, with a particular focus on podocytes. Kidneys from 16 male Caucasian-Americans without overt renal disease, including 4 children (≤3 years old) to define baseline values of early life and 12 adults (≥18 years old), were collected at autopsy in Jackson, Mississippi. We used a combination of immunohistochemistry, confocal microscopy, and design-based stereology to estimate individual glomerular volume (IGV) and numbers of podocytes, nonepithelial cells (NECs; tuft cells other than podocytes), and parietal epithelial cells (PECs). Podocyte density was calculated. Data are reported as medians and interquartile ranges (IQRs). Glomeruli from children were small and contained 452 podocytes (IQR=335-502), 389 NECs (IQR=265-498), and 146 PECs (IQR=111-206). Adult glomeruli contained significantly more cells than glomeruli from children, including 558 podocytes (IQR=431-746; P<0.01), 1383 NECs (IQR=998-2042; P<0.001), and 367 PECs (IQR=309-673; P<0.001). However, large adult glomeruli showed markedly lower podocyte density (183 podocytes per 10(6) µm(3)) than small glomeruli from adults and children (932 podocytes per 10(6) µm(3); P<0.001). In conclusion, large adult glomeruli contained more podocytes than small glomeruli from children and adults, raising questions about the origin of these podocytes. The increased number of podocytes in large glomeruli does not match the increase in glomerular size observed in adults, resulting in relative podocyte depletion. This may render hypertrophic glomeruli susceptible to pathology.
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Affiliation(s)
- Victor G Puelles
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | | | - Luise A Cullen-McEwen
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Jinhua Li
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Michael D Hughson
- Department of Pathology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Wendy E Hoy
- Centre for Chronic Disease, The University of Queensland, Brisbane, Australia
| | - Peter G Kerr
- Department of Nephrology, Monash Medical Centre, Melbourne, Australia; and Department of Medicine, Monash University, Melbourne, Australia
| | - John F Bertram
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia;
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91
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Shin JH, So BI, Song YS, Lee Y, Jang KS, Kim H, Kim KS. Histopathological analyses of diabetic nephropathy in sucrose-fed Otsuka Long-Evans Tokushima fatty rats. Endocr Res 2015; 40:29-36. [PMID: 24833322 DOI: 10.3109/07435800.2014.915848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Otsuka Long-Evans Tokushima fatty (OLETF) rats are an established model of diabetic nephropathy. However, diabetes and diabetic nephropathy (DN) in OLETF rats develop later than in other animal type 2 diabetes models. OBJECTIVES This study was conducted to investigate the serial changes in the histopathological characteristics of DN in sucrose-fed OLETF rats by biochemical and morphometric analyses. METHODS We conducted sucrose feeding to examine the progression of DN. One group of OLETF rats was given water containing 30% sucrose ad libitum (SO) and the other group was given water without 30% sucrose (TO). Consecutive observations were made at 4-week intervals from 16 to 50 weeks of age in TO rats, and from 16 to 42 weeks of age in SO rats. Examination parameters included body weight, serum glucose level, urine albumin-to-creatinine ratio (UACR), light microscopy (LM) and electron microscopy (EM). RESULTS The UACR was over 300 mg/g in 32-week-old SO rats (after 16 weeks of sucrose feeding) and in 38-week-old TO rats. LM indicated that glomerular hypertrophy and mesangial matrix expansion in SO rats increased compared to that of age-matched TO rats especially at 42 weeks of age (p < 0.05). EM also showed that glomerular basement membrane thickness and podocyte foot process width of SO rats were significantly greater than those of age-matched TO rats (p < 0.05). CONCLUSION Our results suggested that dietary manipulation by sucrose feeding may cause deterioration of DN and could hasten the onset of diabetes and DN in OLETF rats.
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Affiliation(s)
- Jeong Hun Shin
- Department of Internal Medicine, Hanyang University College of Medicine , Seoul , Republic of Korea
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92
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Wang SS, Huang QT, Zhong M, Yin Q. AOPPs (advanced oxidation protein products) promote apoptosis in trophoblastic cells through interference with NADPH oxidase signaling: implications for preeclampsia. J Matern Fetal Neonatal Med 2014; 28:1747-55. [DOI: 10.3109/14767058.2014.969231] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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93
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Batkulwar KB, Bansode SB, Patil GV, Godbole RK, Kazi RS, Chinnathambi S, Shanmugam D, Kulkarni MJ. Investigation of phosphoproteome in RAGE signaling. Proteomics 2014; 15:245-59. [DOI: 10.1002/pmic.201400169] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 08/14/2014] [Accepted: 10/06/2014] [Indexed: 12/11/2022]
Affiliation(s)
- Kedar B. Batkulwar
- Proteomics Facility; Division of Biochemical Sciences; CSIR-National Chemical Laboratory; Pune India
| | - Sneha B. Bansode
- Proteomics Facility; Division of Biochemical Sciences; CSIR-National Chemical Laboratory; Pune India
| | - Gouri V. Patil
- Proteomics Facility; Division of Biochemical Sciences; CSIR-National Chemical Laboratory; Pune India
| | - Rashmi K. Godbole
- Proteomics Facility; Division of Biochemical Sciences; CSIR-National Chemical Laboratory; Pune India
| | - Rubina S. Kazi
- Proteomics Facility; Division of Biochemical Sciences; CSIR-National Chemical Laboratory; Pune India
| | | | - Dhanasekaran Shanmugam
- Proteomics Facility; Division of Biochemical Sciences; CSIR-National Chemical Laboratory; Pune India
| | - Mahesh J. Kulkarni
- Proteomics Facility; Division of Biochemical Sciences; CSIR-National Chemical Laboratory; Pune India
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94
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Márquez E, Riera M, Pascual J, Soler MJ. Renin-angiotensin system within the diabetic podocyte. Am J Physiol Renal Physiol 2014; 308:F1-10. [PMID: 25339703 DOI: 10.1152/ajprenal.00531.2013] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Diabetic kidney disease is the leading cause of end-stage renal disease. Podocytes are differentiated cells necessary for the development and maintenance of the glomerular basement membrane and the capillary tufts, as well as the function of the glomerular filtration barrier. The epithelial glomerular cells express a local renin-angiotensin system (RAS) that varies in different pathological situations such as hyperglycemia or mechanical stress. RAS components have been shown to be altered in diabetic podocytopathy, and their modulation may modify diabetic nephropathy progression. Podocytes are a direct target for angiotensin II-mediated injury by altered expression and distribution of podocyte proteins. Furthermore, angiotensin II promotes podocyte injury indirectly by inducing cellular hypertrophy, increased apoptosis, and changes in the anionic charge of the glomerular basement membrane, among other effects. RAS blockade has been shown to decrease the level of proteinuria and delay the progression of chronic kidney disease. This review summarizes the local intraglomerular RAS and its imbalance in diabetic podocytopathy. A better understanding of the intrapodocyte RAS might provide a new approach for diabetic kidney disease treatment.
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Affiliation(s)
- Eva Márquez
- Department of Nephrology, Hospital del Mar, Barcelona, Spain; IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain; and
| | - Marta Riera
- Department of Nephrology, Hospital del Mar, Barcelona, Spain; IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain; and Red de Investigación Renal (REDINREN), Instituto Carlos III, Madrid, Spain
| | - Julio Pascual
- Department of Nephrology, Hospital del Mar, Barcelona, Spain; IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain; and Red de Investigación Renal (REDINREN), Instituto Carlos III, Madrid, Spain
| | - María José Soler
- Department of Nephrology, Hospital del Mar, Barcelona, Spain; IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain; and Red de Investigación Renal (REDINREN), Instituto Carlos III, Madrid, Spain
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95
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Abstract
In diabetic kidney disease, detection of urinary albumin is recommended to aid in diagnosis, evaluate disease severity, and determine effects of therapy. However, because typical histopathologic changes in diabetic kidney disease or early progressive renal decline may occur in patients with normoalbuminuria, urinary albumin may not be sufficient to identify patients with early-stage diabetic kidney disease or to predict its progression. Therefore, intensive efforts have been made to identify novel noninvasive urinary biomarkers to discriminate patients with a higher risk of end-stage renal failure. Because diabetic kidney disease progression is associated with the extent of histologic changes in the glomeruli and the degree of tubulointerstitial changes, urinary biomarkers that accurately reflect the degree of histopathologic damage may be excellent biomarkers. This review article summarizes the clinical significance of new urinary biomarkers in the early detection of diabetic kidney disease.
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96
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Post DM, Hawkins BL, Eldridge JA. The effects of nutrition-induced abnormal food metabolism in the Southern Plains woodrat (Neotoma micropus): comparisons of variations of the Western diet. J Anim Physiol Anim Nutr (Berl) 2014; 99:29-36. [PMID: 25070181 DOI: 10.1111/jpn.12224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 06/12/2014] [Indexed: 11/28/2022]
Abstract
We investigated the effects of several modifications of the Western diet on a medium-sized rodent, Neotoma micropus, that lives in the area of the wildland-urban interface. We conducted a laboratory study of the response of N. micropus to high fat-high fructose (HFHF), high fat-high sucrose (HFHS), high fat-low sugar (HFLSu) and control (low fat-low sugar) diets. We found a significant increase in hepatic lipid deposition and a significant decrease in podocytes in those animals that consumed the HFHF and HFLSu diets compared to those on the HFHS and control diets. We found no significant differences in Bowman's space or hepatic collagen formation. We predict that N. micropus in the wild, with access to anthropogenic resources, will show similar effects as a result of the consumption of anthropogenic resources.
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Affiliation(s)
- D M Post
- Department of Biology, University of Texas-Permian Basin, Odessa, TX, USA
| | | | - J A Eldridge
- Department of Kinesiology, University of Texas-Permian Basin, Odessa, TX, USA
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97
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Filippone EJ, Abubacker F, Farber JL. Posttransplantation normoglycemic diabetic nephropathy: the role of the allograft insulin resistance--a case report. Transplant Proc 2014; 46:2381-5. [PMID: 24984885 DOI: 10.1016/j.transproceed.2014.02.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 02/27/2014] [Indexed: 11/24/2022]
Abstract
BACKGROUND The pathogenesis of diabetic nephropathy is incompletely understood. Although the role of hyperglycemia is well-established, the participation of insulin resistance is increasingly appreciated. Podocytes are insulin responsive cells and require normal insulin signaling for sustained viability. CASE REPORT We have presented a renal transplant recipient with lupus nephritis who received a deceased donor kidney from a patient with diabetes mellitus (DM). The kidney functioned well initially. Within 2 years, however, nephrotic range proteinuria developed, and a biopsy revealed diabetic nephropathy that had clearly evolved in comparison with the implantation biopsy. The recipient was repeatedly normoglycemic with normal glycated hemoglobin and glucose tolerance, and she was found to be quite insulin sensitive on the basis of a low homeostasis model assessment of insulin resistance. CONCLUSIONS We argue that the nephropathy developed in the allograft owing to impaired insulin signaling from intrinsic donor-derived insulin resistance that was exacerbated by low insulin levels in the insulin-sensitive recipient. This case has implications for the most appropriate utilization of kidneys from donors with DM.
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Affiliation(s)
- E J Filippone
- Division of Nephrology, Department of Medicine, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania.
| | - F Abubacker
- Division of Nephrology, Department of Medicine, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania
| | - J L Farber
- Department of Pathology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania
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98
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Filippone EJ, Gupta A, Farber JL. Normoglycemic diabetic nephropathy: the role of insulin resistance. CASE REPORTS IN NEPHROLOGY AND UROLOGY 2014; 4:137-43. [PMID: 25076962 PMCID: PMC4107385 DOI: 10.1159/000364901] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The pathophysiology of diabetic nephropathy (DN) is complex and incompletely understood. Whereas hyperglycemia is clearly important, the role of insulin resistance (IR) is increasingly recognized. We present the case of a normotensive non-smoking obese woman with nephrotic syndrome who was found to have DN by biopsy. All measures of glucose metabolism, including fasting glucose, glycosylated hemoglobin, and oral glucose tolerance testing, were repeatedly normal with little exception. IR was documented, however, based on the presence of the metabolic syndrome and an elevated homeostasis model assessment of IR. We posit that this IR is central to the pathogenesis of our patient's lesion, and this may explain other cases of DN with normoglycemia. The literature supporting this concept is discussed.
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Affiliation(s)
- Edward J Filippone
- Division of Nephrology, Department of Medicine, Thomas Jefferson University Hospital, Philadelphia, Pa., USA
| | - Astha Gupta
- Division of Nephrology, Department of Medicine, Thomas Jefferson University Hospital, Philadelphia, Pa., USA
| | - John L Farber
- Department of Pathology, Thomas Jefferson University Hospital, Philadelphia, Pa., USA
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99
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Kitada M, Kanasaki K, Koya D. Clinical therapeutic strategies for early stage of diabetic kidney disease. World J Diabetes 2014; 5:342-356. [PMID: 24936255 PMCID: PMC4058738 DOI: 10.4239/wjd.v5.i3.342] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 03/08/2014] [Accepted: 04/17/2014] [Indexed: 02/05/2023] Open
Abstract
Diabetic kidney disease (DKD) is the most common cause of chronic kidney disease, leading to end-stage renal disease and cardiovascular disease. The overall number of patients with DKD will continue to increase in parallel with the increasing global pandemic of type 2 diabetes. Based on landmark clinical trials, DKD has become preventable by controlling conventional factors, including hyperglycemia and hypertension, with multifactorial therapy; however, the remaining risk of DKD progression is still high. In this review, we show the importance of targeting remission/regression of microalbuminuria in type 2 diabetic patients, which may protect against the progression of DKD and cardiovascular events. To achieve remission/regression of microalbuminuria, several steps are important, including the early detection of microalbuminuria with continuous screening, targeting HbA1c < 7.0% for glucose control, the use of renin angiotensin system inhibitors to control blood pressure, the use of statins or fibrates to control dyslipidemia, and multifactorial treatment. Reducing microalbuminuria is therefore an important therapeutic goal, and the absence of microalbuminuria could be a pivotal biomarker of therapeutic success in diabetic patients. Other therapies, including vitamin D receptor activation, uric acid-lowering drugs, and incretin-related drugs, may also be promising for the prevention of DKD progression.
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100
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Yokota K, Fukuda M, Matsui Y, Kario K, Kimura K. Visit-to-visit variability of blood pressure and renal function decline in patients with diabetic chronic kidney disease. J Clin Hypertens (Greenwich) 2014; 16:362-6. [PMID: 24712921 PMCID: PMC8032038 DOI: 10.1111/jch.12293] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 01/21/2014] [Accepted: 01/23/2014] [Indexed: 11/27/2022]
Abstract
The authors previously reported that the visit-to-visit variability of blood pressure is correlated with renal function decline in nondiabetic chronic kidney disease. Little is known about the association between visit-to-visit variability and renal function decline in patients with diabetic chronic kidney disease. The authors retrospectively studied 69 patients with diabetic chronic kidney disease stage 3a, 3b, or 4. The standard deviation and coefficient of variation of blood pressure in 12 consecutive visits were defined as visit-to-visit variability of blood pressure. The median observation period was 32 months. In univariate correlation, the standard deviation and coefficient of variation of blood pressure were not significantly associated with the slope of estimated glomerular filtration rate. There was no significant association between the visit-to-visit variability of blood pressure and renal function decline in patients with diabetic chronic kidney disease, in contrast with our previous study of nondiabetic patients with chronic kidney disease.
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Affiliation(s)
- Kei Yokota
- Division of Cardiovascular MedicineDepartment of MedicineSchool of MedicineJichi Medical UniversityTochigiJapan
- Department of NephrologyIwakuni Medical CenterYamaguchiJapan
- Department of Nephrology and HypertensionSchool of MedicineSt. Marianna UniversityKanagawaJapan
| | | | - Yoshio Matsui
- Department of Internal MedicineIwakuni Medical CenterYamaguchiJapan
| | - Kazuomi Kario
- Division of Cardiovascular MedicineDepartment of MedicineSchool of MedicineJichi Medical UniversityTochigiJapan
| | - Kenjiro Kimura
- Department of Nephrology and HypertensionSchool of MedicineSt. Marianna UniversityKanagawaJapan
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