251
|
Makino Y, Haneda M. Insulin in podocyte podiatry. J Diabetes Investig 2011; 2:255-7. [PMID: 24843493 PMCID: PMC4014962 DOI: 10.1111/j.2040-1124.2011.00118.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Yuichi Makino
- Yuichi Makino Tel.: +81‐166‐68‐2454 Fax: +81‐166‐68‐2459
E‐mail address:
| | - Masakazu Haneda
- Division of Metabolism and Biosystemic Science, Department of Medicine, Asahikawa Medical University, Asahikawa, Japan
| |
Collapse
|
252
|
Bu X, Zhou Y, Zhang H, Qiu W, Chen L, Cao H, Fang L, Wen P, Tan R, Yang J. Systemic administration of naked plasmid encoding HGF attenuates puromycin aminonucleoside-induced damage of murine glomerular podocytes. Am J Physiol Renal Physiol 2011; 301:F784-92. [PMID: 21775482 DOI: 10.1152/ajprenal.00210.2011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Podocyte injury is considered to play important roles in the pathogenesis of human glomerular disease. There is accumulating evidence suggesting that hepatocyte growth factor (HGF) elicits preventive activity for glomerular cells in animal models of chronic renal diseases. In this study, we demonstrated that delivery of a naked plasmid vector encoding the human HGF gene into mice by a hydrodynamic-based in vivo gene transfection approach markedly reduced proteinuria and attenuated podocyte injury in a mouse model induced by puromycin aminonucleoside (PAN) injection. Systemic administration by rapid injection via the tail vein of a naked plasmid containing HGF cDNA driven under a cytomegalovirus promoter (pCMV-HGF) produced a remarkable level of human HGF protein in the circulation. Tissue distribution studies suggested that the kidney expressed a high level of the HGF transgene. Meanwhile, compared with tubules and interstitium, a higher level of exogenous HGF protein was detected in the glomeruli. Administration of pCMV-HGF dramatically abated the urine albumin excretion and podocyte injury in PAN nephropathy in mice. Exogenous expression of HGF produced evidently beneficial effects, leading to restoration of Wilms' tumor-1 (WT1) and α-actinin-4 expression and attenuation of ultrastructural damage of the podocytes. In vitro, HGF not only restored WT1 and α-actinin-4 expression but also inhibited albumin leakage of podocytes incubated with PAN in a Transwell culture chamber. These results suggest that HGF might provide a novel strategy for amelioration of podocyte injury.
Collapse
Affiliation(s)
- Xuan Bu
- Center of Kidney Disease, 2nd Affiliated Hospital, Nanjing Medical University, Nanjing, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
253
|
Ma J, Matsusaka T, Yang HC, Zhong J, Takagi N, Fogo AB, Kon V, Ichikawa I. Induction of podocyte-derived VEGF ameliorates podocyte injury and subsequent abnormal glomerular development caused by puromycin aminonucleoside. Pediatr Res 2011; 70:83-9. [PMID: 21451433 PMCID: PMC3113658 DOI: 10.1203/pdr.0b013e31821bdf1c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Our previous studies using puromycin aminonucleoside (PAN) established that podocyte damage leads to glomerular growth arrest during development and glomerulosclerosis later in life. This study examined the potential benefit of maintaining podocyte-derived VEGF in podocyte defense and survival after PAN injury using conditional transgenic podocytes and mice, in which human VEGF-A (hVEGF) transgene expression is controlled by tetracycline responsive element (TRE) promoter and reverse tetracycline transactivator (rtTA) in podocytes. In vitro experiments used primary cultured podocytes harvested from mice carrying podocin-rtTA and TRE-hVEGF transgenes, in which hVEGF can be induced selectively. Induction of VEGF in PAN-exposed podocytes resulted in preservation of intrinsic VEGF, α-actinin-4 and synaptopodin, antiapoptotic marker Bcl-xL/Bax, as well as attenuation in apoptotic marker cleaved/total caspase-3. In vivo, compared with genotype controls, PAN-sensitive neonatal mice with physiologically relevant levels of podocyte-derived VEGF showed significantly larger glomeruli. Furthermore, PAN-induced up-regulation of desmin, down-regulation of synaptopodin and nephrin, and disruption of glomerular morphology were significantly attenuated in VEGF-induced transgenic mice. Our data indicate that podocyte-derived VEGF provides self-preservation functions, which can rescue the cell after injury and preempt subsequent deterioration of the glomerulus in developing mice.
Collapse
Affiliation(s)
- Ji Ma
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA.
| | | | | | | | | | | | | | | |
Collapse
|
254
|
Jefferson JA, Alpers CE, Shankland SJ. Podocyte biology for the bedside. Am J Kidney Dis 2011; 58:835-45. [PMID: 21715071 DOI: 10.1053/j.ajkd.2011.03.033] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2010] [Accepted: 03/03/2011] [Indexed: 12/14/2022]
Abstract
The explosion of podocyte biology during the last decade has radically altered our views on the pathophysiologic process of proteinuria, glomerular disease, and progressive kidney disease. In this review, we highlight some of these landmark findings, but focus on recent advances in the field and implications for translating this biology into therapy for podocyte diseases.
Collapse
Affiliation(s)
- J Ashley Jefferson
- Division of Nephrology, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA.
| | | | | |
Collapse
|
255
|
Weil EJ, Lemley KV, Yee B, Lovato T, Richardson M, Myers BD, Nelson RG. Podocyte detachment in type 2 diabetic nephropathy. Am J Nephrol 2011; 33 Suppl 1:21-4. [PMID: 21659731 DOI: 10.1159/000327047] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Glomerular podocyte number declines and urinary excretion of podocytes increases as kidney disease progresses in persons with type 2 diabetes mellitus (T2DM). METHODS Using high-power electron microscopy, we quantified podocyte detachment in T2DM. RESULTS We evaluated 106 glomeruli (range 1-6 per subject) from 40 Pima Indian subjects with T2DM enrolled in a clinical trial. On high-power electron micrographs, 35% of the subjects had no evidence of podocyte detachment. Among the remaining subjects, the median percentage of basement membrane with podocyte detachment was 0.62% (interquartile range = 0.32-1.52%). CONCLUSION Podocyte detachment from the glomerular basement membrane has been described and measured in type 1 diabetes mellitus using a different method. We now document podocyte detachment microscopically and quantify it morphometrically in humans with T2DM. The findings offer quantitative histologic support to a potential mechanism for the functional impairment, and possibly the sclerosis of glomeruli, in diabetic glomerular injury.
Collapse
Affiliation(s)
- E Jennifer Weil
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Phoenix, AZ, USA
| | | | | | | | | | | | | |
Collapse
|
256
|
Devaraj S, Tobias P, Kasinath BS, Ramsamooj R, Afify A, Jialal I. Knockout of toll-like receptor-2 attenuates both the proinflammatory state of diabetes and incipient diabetic nephropathy. Arterioscler Thromb Vasc Biol 2011; 31:1796-804. [PMID: 21617141 DOI: 10.1161/atvbaha.111.228924] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Type 1 diabetes (T1DM) is a proinflammatory state and confers an increased risk for vascular complications. Toll-like receptors (TLR) could participate in diabetic vasculopathies. Whether TLR activation contributes to the proinflammatory state of T1DM and the pathogenesis of diabetic nephropathy remains unknown. METHODS AND RESULTS We induced T1DM in TLR2 knockout mice (TLR2-/-) and wild-type littermates (C57BL/6J-WT) using streptozotocin (STZ). Fasting blood, peritoneal macrophages, and kidneys were obtained for flow cytometry, Western blot, microscopy, and cytokine assays at 6 and 14 weeks after induction of diabetes. Macrophage TLR2 expression and MyD88-dependent signaling were increased in diabetic mice (WT+STZ) compared with nondiabetic WT mice. These biomarkers were attenuated in diabetic TLR2-/- macrophages. WT+STZ mice showed increased kidney:body weight ratio due to cell hypertrophy, increased albuminuria, decreased kidney nephrin, podocin, and podocyte number and increased transforming growth factor-β and laminin compared with WT mice. Nephrin, podocin, and podocyte number and effacement were restored, and transforming growth factor-β and laminin levels were decreased in TLR2-/-+ STZ mice kidneys versus WT+STZ. Peritoneal and kidney macrophages were predominantly M1 phenotype in WT+STZ mice; this was attenuated in TLR2-/-+STZ mice. CONCLUSIONS These data support a role for TLR2 in promoting inflammation and early changes of incipient diabetic nephropathy, in addition to albuminuria and podocyte loss.
Collapse
Affiliation(s)
- Sridevi Devaraj
- Laboratory for Atherosclerosis and Metabolic Research, Department of Pathology and Laboratory Medicine, University of California at Davis Medical Center, Sacramento, CA 95817, USA
| | | | | | | | | | | |
Collapse
|
257
|
Kato H, Gruenwald A, Suh JH, Miner JH, Barisoni-Thomas L, Taketo MM, Faul C, Millar SE, Holzman LB, Susztak K. Wnt/β-catenin pathway in podocytes integrates cell adhesion, differentiation, and survival. J Biol Chem 2011; 286:26003-15. [PMID: 21613219 DOI: 10.1074/jbc.m111.223164] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Diabetic kidney disease (DKD) is the single most common cause of albuminuria and end-stage kidney disease in the United States. We found increased expression of Wnt/β-catenin (Ctnnb1) pathway transcripts and proteins in glomeruli and podocytes of patients and mouse models of DKD. Mice with podocyte-specific expression of stabilized Ctnnb1 exhibited basement membrane abnormalities, albuminuria, and increased susceptibility to glomerular injury. Mice with podocyte-specific deletion of Ctnnb1 or podocyte-specific expression of the canonical Wnt inhibitor Dickkopf-related protein 1 (Dkk1) also showed increased susceptibility to DKD. Podocytes with stabilized Ctnnb1 were less motile and less adhesive to different matrices. Deletion of Ctnnb1 in cultured podocytes increased the expression of podocyte differentiation markers and enhanced cell motility; however, these cells were more susceptible to apoptosis. These results indicate that Wnt/Ctnnb1 signaling in podocytes plays a critical role in integrating cell adhesion, motility, cell death, and differentiation. Balanced Ctnnb1 expression is critical for glomerular filtration barrier maintenance.
Collapse
Affiliation(s)
- Hideki Kato
- Department of Medicine, Division of Nephrology, Albert Einstein College of Medicine, New York, New York 10461, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
258
|
Dysregulation of the intrarenal vitamin D endocytic pathway in a nephropathy-prone mouse model of type 1 diabetes. EXPERIMENTAL DIABETES RESEARCH 2011; 2011:269378. [PMID: 21747824 PMCID: PMC3123992 DOI: 10.1155/2011/269378] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Revised: 03/17/2011] [Accepted: 03/18/2011] [Indexed: 11/26/2022]
Abstract
Microalbuminuria in humans with Type 1 diabetes (T1D) is associated with increased urinary excretion of megalin, as well as many megalin ligands, including vitamin-D-binding protein (VDBP). We examined the DBA/2J diabetic mouse, nephropathy prone model, to determine if megalin and VDBP excretion coincide with the development of diabetic nephropathy. Megalin, VDBP, and 25-hydroxy-vitamin D (25-OHD) were measured in urine, and genes involved in vitamin D metabolism were assessed in renal tissues from diabetic and control mice at 10, 15, and 18 weeks following the onset of diabetes. Megalin, VDBP, and 25-OHD were increased in the urine of diabetic mice. 1-α hydroxylase (CYP27B1) mRNA in the kidney was persistently increased in diabetic mice, as were several vitamin D-target genes. These studies show that intrarenal vitamin D handling is altered in the diabetic kidney, and they suggest that in T1D, urinary losses of VDBP may portend risk for intrarenal and extrarenal vitamin D deficiencies.
Collapse
|
259
|
Effects of angiotensin receptor blocker on phenotypic alterations of podocytes in early diabetic nephropathy. Am J Med Sci 2011; 341:207-14. [PMID: 21326079 DOI: 10.1097/maj.0b013e3182010da9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND Emerging evidence suggests that podocyte injury is a crucial event in the stage of diabetic nephropathy (DN), a process in which angiotensin II is implicated. In this study, the authors investigated the influence of irbesartan, an angiotensin receptor blocker, on the phenotypic alterations of podocytes in experimental DN. METHODS DN was induced by combination of high-sucrose, high-fat diet and intraperitoneal injection of low dose of streptozotocin (35 mg/kg) in spontaneously hypertensive rats. Diabetic rats were treated with irbesartan (50 mg/kg/d) by gavage for 8 weeks. Nondiabetic normotensive Wistar-Kyoto rats, which have the same genetic background as spontaneously hypertensive rat, were used as controls. The renal histological changes were investigated by light and electron microscopy. The epithelial marker of nephrin and mesenchymal marker of desmin were detected by real-time reverse transcriptase-polymerase chain reaction and Western blotting. RESULTS Compared with controls, diabetic rats were associated with mesangial matrix deposition, thickening of glomerular basement membrane, albuminuria, loss of podocytes and effacement of foot processes. Furthermore, the expression of nephrin was significantly reduced whereas desmin was increased. Irbesartan treatment not only lowered blood pressure and albuminuria but also attenuated podocyte loss, maintenance of nephrin expression and inhibition of desmin expression. CONCLUSIONS This study demonstrates that early irbesartan intervention attenuates the podocyte damage and ameliorates phenotypic alterations of podocytes, which provides a novel insight for the early application of angiotensin receptor blocker to prevent the development of DN.
Collapse
|
260
|
Nauta FL, Boertien WE, Bakker SJL, van Goor H, van Oeveren W, de Jong PE, Bilo H, Gansevoort RT. Glomerular and tubular damage markers are elevated in patients with diabetes. Diabetes Care 2011; 34:975-81. [PMID: 21307379 PMCID: PMC3064060 DOI: 10.2337/dc10-1545] [Citation(s) in RCA: 156] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE We investigated in a cross-sectional study the levels of serum and urinary damage markers in diabetic patients (n = 94) and nondiabetic control subjects (n = 45) to study the association of glomerular (IgG), proximal tubular (kidney injury molecule [KIM]-1, N-acetyl-β-d-glucosaminidase [NAG], neutrophil gelatinase-associated lipocalin [NGAL], and cystatin C), and distal tubular (heart fatty acid-binding protein [H-FABP]) damage markers with kidney disease severity, as assessed by albuminuria and estimated glomerular filtration rate (eGFR). RESEARCH DESIGN AND METHODS Damage markers were measured in triplicate in fresh morning urine samples and in plasma. RESULTS Of the diabetic patients, 41 were normoalbuminuric, 41 were microalbuminuric, and 12 were macroalbuminuric. Urinary NAG (ninefold), NGAL (1.5-fold), and H-FABP (3.5-fold) were significantly elevated in normoalbuminuric diabetic patients compared with nondiabetic control subjects. Urinary concentrations of all markers increased per albuminuria stratum, except KIM-1. All urinary damage markers, except KIM-1, were significantly associated with albuminuria, independent of age, sex, and plasma concentrations of the corresponding biomarker (standard βs between 0.35 and 0.87; all P ≤ 0.001). All urinary damage markers, except KIM-1, were significantly associated with the eGFR in univariate models (standard βs between -0.38 and -0.21; all P < 0.04). After adjusting for age, sex, plasma concentration of the corresponding damage marker, and albuminuria, only the association of H-FABP with eGFR remained significant (standard β -0.26; P = 0.037). CONCLUSIONS Glomerular and tubular markers are associated with albuminuria, independently of eGFR, suggesting that albuminuria reflects both glomerular and tubulointerstitial damage. Only urinary H-FABP is associated with eGFR independently of albuminuria and, therefore, may be a promising urinary damage marker to assess diabetic kidney disease.
Collapse
Affiliation(s)
- Ferdau L Nauta
- Department of Nephrology, University Medical Center Groningen, University of Groningen,Groningen, the Netherlands.
| | | | | | | | | | | | | | | |
Collapse
|
261
|
Olsen AS, Sarras MP, Intine RV. Limb regeneration is impaired in an adult zebrafish model of diabetes mellitus. Wound Repair Regen 2011; 18:532-42. [PMID: 20840523 DOI: 10.1111/j.1524-475x.2010.00613.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The zebrafish (Danio rerio) is an established model organism for the study of developmental processes, human disease, and tissue regeneration. We report that limb regeneration is severely impaired in our newly developed adult zebrafish model of type I diabetes mellitus. Intraperitoneal streptozocin injection of adult, wild-type zebrafish results in a sustained hyperglycemic state as determined by elevated fasting blood glucose values and increased glycation of serum protein. Serum insulin levels are also decreased and pancreas immunohistochemisty revealed a decreased amount of insulin signal in hyperglycemic fish. Additionally, the diabetic complications of retinal thinning and glomerular basement membrane thickening (early signs of retinopathy and nephropathy) resulting from the hyperglycemic state were evident in streptozocin-injected fish at 3 weeks. Most significantly, limb regeneration, following caudal fin amputation, is severely impaired in diabetic zebrafish and nonspecific toxic effects outside the pancreas were not found to contribute to impaired limb regeneration. This experimental system using adult zebrafish facilitates a broad spectrum of genetic and molecular approaches to study regeneration in the diabetic background.
Collapse
Affiliation(s)
- Ansgar S Olsen
- Department of Cell Biology and Anatomy, Dr William M Scholl College of Podiatric Medicine, Rosalind Franklin University, North Chicago, Illinois, USA
| | | | | |
Collapse
|
262
|
Regression of superficial glomerular podocyte injury in type 2 diabetic rats with overt albuminuria: effect of angiotensin II blockade. J Hypertens 2011; 28:2289-98. [PMID: 20706133 DOI: 10.1097/hjh.0b013e32833dfcda] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVE Clinical studies indicate that the remission, regression or both of nephrotic-range albuminuria are exerted by angiotensin II receptor blockers (ARBs) in diabetes. The current study was performed to test the hypothesis that these effects of ARBs are associated with regression of glomerular podocyte injury. METHODS We examined the effects of an ARB, olmesartan, on glomerular podocyte injury in type 2 diabetic Otsuka-Long-Evans-Tokushima-Fatty rats with overt albuminuria. RESULTS At baseline (55-week-old), diabetic Otsuka-Long-Evans-Tokushima-Fatty rats showed severe albuminuria with desmin-positive areas (an index of podocyte injury) in both superficial and juxtamedullary glomeruli, and podocyte injury was much greater in juxtamedullary than in superficial glomeruli. At 75-week-old, Otsuka-Long-Evans-Tokushima-Fatty rats had developed more severe albuminuria and superficial glomerular podocyte injury, whereas juxtamedullary glomerular podocyte injury did not advance further. Olmesartan (10 mg/kg per day) decreased albuminuria and superficial glomerular desmin staining to levels that were lower than those at baseline, whereas advanced juxtamedullary glomerular podocyte injury was not changed. CONCLUSION The current study demonstrates for the first time that juxtamedullary glomerular podocyte injury reaches a severe condition at an earlier time than superficial glomerular podocyte injury during the progression of overt albuminuria in type 2 diabetic rats. Our data also support the hypothesis that the antialbuminuric effects of ARBs are associated with regression of superficial glomerular podocyte injury in type 2 diabetes with nephrotic-range albuminuria.
Collapse
|
263
|
Kuritzky L, Toto R, Van Buren P. Identification and Management of Albuminuria in the Primary Care Setting. J Clin Hypertens (Greenwich) 2011; 13:438-49. [DOI: 10.1111/j.1751-7176.2010.00424.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
264
|
Campbell KN, Raij L, Mundel P. Role of angiotensin II in the development of nephropathy and podocytopathy of diabetes. Curr Diabetes Rev 2011; 7:3-7. [PMID: 21067505 PMCID: PMC3690294 DOI: 10.2174/157339911794273973] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Accepted: 09/10/2010] [Indexed: 01/03/2023]
Abstract
Diabetic kidney disease is the leading cause of end-stage renal disease worldwide. Podocytes are highly differentiated, pericyte-like cells that are essential for normal function of the kidney filter. Loss of podocytes is a hallmark of progressive kidney diseases including diabetic nephropathy. Podocytes are a direct target for angiotensin II - mediated injury by altered expression and distribution of podocyte proteins. Additionally, angiotensin II promotes podocyte injury indirectly by increasing calcium influx and production of reactive oxygen species. Notwithstanding the convincing rationale for angiotensin II blockade as a treatment modality, the incidence of diabetes-related end stage renal disease has increased steadily despite widespread use of angiotensin converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs). Recently published clinical trials have rekindled a debate on the safety and efficacy of dual blockade of the renin-angiotensin system (RAS). This review summarizes the rationale for blockade of angiotensin II as a therapeutic target in treating diabetic kidney disease, including the critical role played by podocytes. Recent relevant clinical trials on the role of RAS blockade in the treatment of diabetic kidney disease are discussed.
Collapse
Affiliation(s)
- Kirk N Campbell
- Department of Medicine, Leonard Miller School of Medicine, University of Miami, 1580 NW 10th Avenue, Miami, FL 33136, USA.
| | | | | |
Collapse
|
265
|
Rafiq K, Hitomi H, Nakano D, Nishiyama A. Pathophysiological roles of aldosterone and mineralocorticoid receptor in the kidney. J Pharmacol Sci 2010; 115:1-7. [PMID: 21186336 DOI: 10.1254/jphs.10r07cr] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
Aldosterone, a steroid hormone, has traditionally been viewed as a key regulator of fluid and electrolyte homeostasis, as well as blood pressure, through the activation of mineralocorticoid receptor (MR). However, a number of studies performed in the last decade have revealed an important role of aldosterone/MR in the pathogenesis of renal injury. Aldosterone/MR-induced renal tissue injury is associated with increased renal inflammation and oxidative stress, fibrosis, mesangial cell proliferation, and podocyte injury, probably through genomic and non-genomic pathways. However, our preliminary data have indicated that acute administration of aldosterone or a selective MR antagonist, eplerenone, does not change blood pressure, heart rate, or renal blood flow. These data suggest that aldosterone/MR induces renal injury through mechanisms that are independent of acute changes in systemic and renal hemodynamics. In this review, we will briefly summarize the roles of aldosterone/MR in the pathogenesis of renal injury, focusing on the underlying mechanisms that are independent of systemic and renal hemodynamic changes.
Collapse
Affiliation(s)
- Kazi Rafiq
- Department of Pharmacology, Kagawa University Medical School, Japan
| | | | | | | |
Collapse
|
266
|
Wang XX, Jiang T, Shen Y, Caldas Y, Miyazaki-Anzai S, Santamaria H, Urbanek C, Solis N, Scherzer P, Lewis L, Gonzalez FJ, Adorini L, Pruzanski M, Kopp JB, Verlander JW, Levi M. Diabetic nephropathy is accelerated by farnesoid X receptor deficiency and inhibited by farnesoid X receptor activation in a type 1 diabetes model. Diabetes 2010; 59:2916-27. [PMID: 20699418 PMCID: PMC2963551 DOI: 10.2337/db10-0019] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE The pathogenesis of diabetic nephropathy is complex and involves activation of multiple pathways leading to kidney damage. An important role for altered lipid metabolism via sterol regulatory element binding proteins (SREBPs) has been recently recognized in diabetic kidney disease. Our previous studies have shown that the farnesoid X receptor (FXR), a bile acid-activated nuclear hormone receptor, modulates renal SREBP-1 expression. The purpose of the present study was then to determine if FXR deficiency accelerates type 1 diabetic nephropathy in part by further stimulation of SREBPs and related pathways, and conversely, if a selective FXR agonist can prevent the development of type 1 diabetic nephropathy. RESEARCH DESIGN AND METHODS Insulin deficiency and hyperglycemia were induced with streptozotocin (STZ) in C57BL/6 FXR KO mice. Progress of renal injury was compared with nephropathy-resistant wild-type C57BL/6 mice given STZ. DBA/2J mice with STZ-induced hyperglycemia were treated with the selective FXR agonist INT-747 for 12 weeks. To accelerate disease progression, all mice were placed on the Western diet after hyperglycemia development. RESULTS The present study demonstrates accelerated renal injury in diabetic FXR KO mice. In contrast, treatment with the FXR agonist INT-747 improves renal injury by decreasing proteinuria, glomerulosclerosis, and tubulointerstitial fibrosis, and modulating renal lipid metabolism, macrophage infiltration, and renal expression of SREBPs, profibrotic growth factors, and oxidative stress enzymes in the diabetic DBA/2J strain. CONCLUSIONS Our findings indicate a critical role for FXR in the development of diabetic nephropathy and show that FXR activation prevents nephropathy in type 1 diabetes.
Collapse
MESH Headings
- Animals
- Crosses, Genetic
- DNA Primers
- Diabetes Mellitus, Experimental/pathology
- Diabetes Mellitus, Experimental/physiopathology
- Diabetes Mellitus, Type 1/pathology
- Diabetes Mellitus, Type 1/physiopathology
- Diabetic Nephropathies/pathology
- Diabetic Nephropathies/physiopathology
- Diabetic Nephropathies/prevention & control
- Female
- Foam Cells/pathology
- Kidney/pathology
- Kidney/physiopathology
- Kidney Glomerulus/pathology
- Macrophages/pathology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Inbred DBA
- Mice, Knockout
- Polymerase Chain Reaction
- Receptors, Cytoplasmic and Nuclear/deficiency
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/physiology
Collapse
Affiliation(s)
- Xiaoxin X. Wang
- Department of Medicine, University of Colorado Denver, and the VA Medical Center, Aurora, Colorado
| | - Tao Jiang
- Department of Medicine, University of Colorado Denver, and the VA Medical Center, Aurora, Colorado
| | - Yan Shen
- Department of Medicine, University of Colorado Denver, and the VA Medical Center, Aurora, Colorado
| | - Yupanqui Caldas
- Department of Medicine, University of Colorado Denver, and the VA Medical Center, Aurora, Colorado
| | - Shinobu Miyazaki-Anzai
- Department of Medicine, University of Colorado Denver, and the VA Medical Center, Aurora, Colorado
| | - Hannah Santamaria
- Department of Medicine, University of Colorado Denver, and the VA Medical Center, Aurora, Colorado
| | - Cydney Urbanek
- Department of Medicine, University of Colorado Denver, and the VA Medical Center, Aurora, Colorado
| | - Nathaniel Solis
- Department of Medicine, University of Colorado Denver, and the VA Medical Center, Aurora, Colorado
| | - Pnina Scherzer
- Nephrology and Hypertension Services, Hadassah University Hospital, Jerusalem, Israel
| | - Linda Lewis
- Department of Medicine, University of Colorado Denver, and the VA Medical Center, Aurora, Colorado
| | - Frank J. Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | | | | | - Jeffrey B. Kopp
- Kidney Disease Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Jill W. Verlander
- Department of Medicine, Division of Nephrology, Hypertension, and Transplantation, University of Florida, Gainesville, Florida
| | - Moshe Levi
- Department of Medicine, University of Colorado Denver, and the VA Medical Center, Aurora, Colorado
- Corresponding author: Moshe Levi,
| |
Collapse
|
267
|
O’Seaghdha CM, Hwang SJ, Upadhyay A, Meigs JB, Fox CS. Predictors of incident albuminuria in the Framingham Offspring cohort. Am J Kidney Dis 2010; 56:852-60. [PMID: 20599306 PMCID: PMC3198053 DOI: 10.1053/j.ajkd.2010.04.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Accepted: 04/07/2010] [Indexed: 12/14/2022]
Abstract
BACKGROUND Predictors for incident albuminuria are not well known in population-based cohorts. The purpose of this study is to identify predictors of incident albuminuria in an unselected middle-aged population. STUDY DESIGN Observational cohort study. SETTING & PARTICIPANTS Framingham Offspring Study participants who attended both the sixth (baseline; 1995-1998) and eighth (2005-2008) examination cycles. PREDICTORS Standard clinical predictors were used. Predictors of incident albuminuria were identified using stepwise logistic regression analysis with age and sex forced into the model. OUTCOMES & MEASUREMENTS Albuminuria was defined as urine albumin-creatinine ratio (UACR) ≥ 17 mg/g (men) or ≥ 25 mg/g (women). Individuals with albuminuria at baseline were excluded. RESULTS 1,916 participants were available for analysis (mean age, 56 years; 54% women). Albuminuria developed in 10.0% of participants (n = 192) during 9.5 years. Age (OR, 2.09; P < 0.001), baseline diabetes (OR, 1.93; P = 0.01), smoking (OR, 2.09; P < 0.001), and baseline log UACR (OR per 1-SD increase in log UACR, 1.56; P < 0.001) were associated with incident albuminuria in a stepwise model. An inverse relationship with female sex (OR, 0.53; P < 0.001) and high-density lipoprotein (HDL) cholesterol level (OR, 0.80; P = 0.007) also was observed. Results were similar when participants with baseline chronic kidney disease (n = 102), defined as estimated glomerular filtration rate <60 mL/min/1.73 m(2), were excluded from the model. Age, male sex, low HDL cholesterol level, smoking, and log UACR continued to be associated with incident albuminuria when baseline diabetes (n = 107) was excluded. Age, male sex, and log UACR correlated with incident albuminuria after participants with baseline hypertension were excluded (n = 651). LIMITATIONS Causality may not be inferred because of the observational nature of the study. One-third of participants did not return for follow-up, potentially attenuating the observed risks of albuminuria. CONCLUSIONS The known cardiovascular risk factors of increasing age, male sex, diabetes, smoking, low HDL cholesterol level, and albuminuria within the reference range are correlates of incident albuminuria in the general population.
Collapse
Affiliation(s)
- Conall M. O’Seaghdha
- Renal Division, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA
- National Heart, Lung and Blood Institute’s Framingham Heart Study and the Center for Population Studies, Framingham, MA
| | - Shih-Jen Hwang
- National Heart, Lung and Blood Institute’s Framingham Heart Study and the Center for Population Studies, Framingham, MA
| | - Ashish Upadhyay
- Division of Nephrology, Tufts Medical Center and Tufts University School of Medicine, Boston, MA
| | - James B. Meigs
- General Medicine Division, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Caroline S. Fox
- National Heart, Lung and Blood Institute’s Framingham Heart Study and the Center for Population Studies, Framingham, MA
- Division of Endocrinology, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA
| |
Collapse
|
268
|
Cai Y, Chen J, Jiang J, Cao W, He L. Zhen-wu-tang, a blended traditional Chinese herbal medicine, ameliorates proteinuria and renal damage of streptozotocin-induced diabetic nephropathy in rats. JOURNAL OF ETHNOPHARMACOLOGY 2010; 131:88-94. [PMID: 20547220 DOI: 10.1016/j.jep.2010.06.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2009] [Revised: 05/20/2010] [Accepted: 06/04/2010] [Indexed: 05/29/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Zhen-wu-tang (ZWT) is a blended traditional Chinese medicine specifically used for various kidney diseases. AIM OF THE STUDY The present study is to evaluate the effects of ZWT on diabetic nephropathy and investigate the potential anti-diabetic mechanisms. MATERIALS AND METHODS Streptozotocin (STZ)-induced diabetic rats were orally administrated ZWT (80,320 mg/kg b.w.) once a day, for a period of 12 weeks. Body weight, urinary volume, urine protein and blood biochemical parameters were measured every 3 weeks. At the end of the observation period, kidneys were isolated for histology, angiotensin II content determination, real time PCR and Western blot analyses. RESULTS ZWT (320 mg/kg b.w.) prevented body weight loss, reduced polyurea, urinary protein excretion, serum creatinine and blood urea nitrogen, although it did not alter the hyperglycemia. It ameliorated glomerular hypertrophy and expansion of the mesangial area, swell and effacement of foot process. It also suppressed the increased expression of angiotensin II, nephrin and podocin. CONCLUSIONS Data from this study suggest that ZWT possess a protective effect on renal damage of STZ-induced diabetic nephropathy in rats, by suppressing hyperactivity of renal renin-angiotensin system that turns in to modulate renal nephrin and podocin expressions, thereby protecting podocyte from injury.
Collapse
Affiliation(s)
- Yu Cai
- College of Pharmacy, Jinan University, China
| | | | | | | | | |
Collapse
|
269
|
Maehira F, Ishimine N, Miyagi I, Eguchi Y, Shimada K, Kawaguchi D, Oshiro Y. Anti-diabetic effects including diabetic nephropathy of anti-osteoporotic trace minerals on diabetic mice. Nutrition 2010; 27:488-95. [PMID: 20708379 DOI: 10.1016/j.nut.2010.04.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Revised: 12/01/2009] [Accepted: 04/20/2010] [Indexed: 01/20/2023]
Abstract
OBJECTIVE In our previous study to evaluate the effects of soluble silicon (Si) on bone metabolism, Si and coral sand (CS) as a natural Si-containing material suppressed peroxisome proliferator-activated receptor γ (PPARγ), which regulates both glucose and bone metabolism and increases adipogenesis at the expense of osteogenesis, leading to bone loss. In this study, we investigated the anti-diabetic effects of bone-seeking elements, Si and stable strontium (Sr), and CS as a natural material containing these elements using obese diabetic KKAy mice. METHODS Weanling male mice were fed diets containing 1% Ca supplemented with CaCO(3) as the control and CS, and diets supplemented with 50 ppm Si or 750 ppm Sr to control diet for 56 d. The mRNA expressions related to energy expenditure in the pancreas and kidney were quantified by real-time polymerase chain reaction. RESULTS At the end of feeding, plasma glucose, insulin, leptin, and adiponectin levels decreased significantly in three test groups, while pancreatic PPARγ and adiponectin mRNA expression levels increased significantly toward the normal level, improving the glucose sensitivity of β-cells and inducing a significant decrease in insulin expression. The renal PPARγ, PPARα, and adiponectin expression levels, histologic indices of diabetic glomerulopathy, and plasma indices of renal function were also improved significantly in the test groups. CONCLUSION Taken together, anti-osteoporotic trace minerals, Si and Sr, and CS containing them showed novel anti-diabetic effects of lowering blood glucose level, improving the tolerance to insulin, leptin, and adiponectin, and reducing the risk of glomerulopathy through modulation of related gene expression in the pancreas and kidney.
Collapse
Affiliation(s)
- Fusako Maehira
- Department of Biometabolic Chemistry, School of Health Sciences, Faculty of Medicine, University of the Ryukyus, Nishihara, Okinawa, Japan.
| | | | | | | | | | | | | |
Collapse
|
270
|
Lin CL, Wang FS, Hsu YC, Chen CN, Tseng MJ, Saleem MA, Chang PJ, Wang JY. Modulation of notch-1 signaling alleviates vascular endothelial growth factor-mediated diabetic nephropathy. Diabetes 2010; 59:1915-25. [PMID: 20522599 PMCID: PMC2911050 DOI: 10.2337/db09-0663] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Disturbances in podocytes are typically associated with marked proteinuria, a hallmark of diabetic nephropathy. This study was conducted to investigate modulation of Notch-1 signaling in high glucose (HG)-stressed human podocytes and in a diabetic animal model. RESEARCH DESIGN AND METHODS Expression of the Notch signaling components was examined in HG-treated podocytes, human embryonic kidney cells (HEK293), and kidneys from diabetic animals by RT-qPCR, Western blot analysis, and immunohistochemical staining. The association between the Notch signaling, VEGF expression, and podocyte integrity was evaluated. RESULTS Notch-1 signaling was significantly activated in HG-cultured human podocytes and HEK293 cells and kidneys from diabetic animals. HG also augmented VEGF expression, decreasing nephrin expression and podocyte number-a critical event for the development of proteinuria in diabetic nephropathy. After use of pharmacological modulators or specific shRNA knockdown strategies, inhibition of Notch-1 signaling significantly abrogated VEGF activation and nephrin repression in HG-stressed cells and ameliorated proteinuria in the diabetic kidney. CONCLUSIONS Our findings suggest that upregulation of Notch-1 signaling in HG-treated renal podocytes induces VEGF expression and subsequent nephrin repression and apoptosis. Modulation of Notch-1 signaling may hold promise as a novel therapeutic strategy for the treatment of diabetic nephropathy.
Collapse
Affiliation(s)
- Chun-Liang Lin
- Department of Nephrology, Chang Gung Memorial Hospital atChiayi, Chiayi, Taiwan.
| | | | | | | | | | | | | | | |
Collapse
|
271
|
Hudkins KL, Pichaiwong W, Wietecha T, Kowalewska J, Banas MC, Spencer MW, Mühlfeld A, Koelling M, Pippin JW, Shankland SJ, Askari B, Rabaglia ME, Keller MP, Attie AD, Alpers CE. BTBR Ob/Ob mutant mice model progressive diabetic nephropathy. J Am Soc Nephrol 2010; 21:1533-42. [PMID: 20634301 DOI: 10.1681/asn.2009121290] [Citation(s) in RCA: 168] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
There remains a need for robust mouse models of diabetic nephropathy (DN) that mimic key features of advanced human DN. The recently developed mouse strain BTBR with the ob/ob leptin-deficiency mutation develops severe type 2 diabetes, hypercholesterolemia, elevated triglycerides, and insulin resistance, but the renal phenotype has not been characterized. Here, we show that these obese, diabetic mice rapidly develop morphologic renal lesions characteristic of both early and advanced human DN. BTBR ob/ob mice developed progressive proteinuria beginning at 4 weeks. Glomerular hypertrophy and accumulation of mesangial matrix, characteristic of early DN, were present by 8 weeks, and glomerular lesions similar to those of advanced human DN were present by 20 weeks. By 22 weeks, we observed an approximately 20% increase in basement membrane thickness and a >50% increase in mesangial matrix. Diffuse mesangial sclerosis (focally approaching nodular glomerulosclerosis), focal arteriolar hyalinosis, mesangiolysis, and focal mild interstitial fibrosis were present. Loss of podocytes was present early and persisted. In summary, BTBR ob/ob mice develop a constellation of abnormalities that closely resemble advanced human DN more rapidly than most other murine models, making this strain particularly attractive for testing therapeutic interventions.
Collapse
Affiliation(s)
- Kelly L Hudkins
- Department of Pathology, University of Washington, Seattle, Washington, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
272
|
Gao Q, Shen W, Qin W, Zheng C, Zhang M, Zeng C, Wang S, Wang J, Zhu X, Liu Z. Treatment of db/db diabetic mice with triptolide: a novel therapy for diabetic nephropathy. Nephrol Dial Transplant 2010; 25:3539-47. [PMID: 20483955 DOI: 10.1093/ndt/gfq245] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Current research on the progression of diabetic nephropathy (DN) suggests many important factors; metabolic disturbance, haemodynamic abnormity, chronic inflammation, oxidative stress, innate immune system activation and podocyte lesion. Triptolide, which is active diterpene purified from the traditional Chinese medicine Tripterygium wilfordii Hook F (TwHF), has anti-inflammatory, anti-oxidative, immunosuppressive and podocyte-protective effects. Herein, we investigated the therapeutic effects of triptolide on DN in db/db diabetic mice and studied the potential mechanisms. METHODS db/db mice with DN were administrated with triptolide or valsartan. After 4, 8 and 12 weeks of treatment, 24-h urine albumin level, blood biochemical parameters and body weight were measured. Glomerulus area, glomerulus volume to Bowman's capsule volume ratio, podocyte changes and inflammatory and oxidative stress markers were quantitatively determined to evaluate renal lesions. RESULTS The albuminuria in db/db diabetic mice was markedly attenuated after triptolide treatment, accompanied with alleviated glomerular hypertrophy and podocyte injury. In addition, the inflammation and oxidative stress in the kidneys were also attenuated, accompanied with improved hyperlipidaemia and obesity. The efficacy increased with the prolonging of triptolide treatment, and the efficacy in high-dose triptolide group was superior to that in the low-dose group. The effect of triptolide on glomerular hypertrophy was similar to valsartan, but the effects of triptolide on renal inflammation and oxidative stress were more profound than those of valsartan. CONCLUSIONS Triptolide can dramatically attenuate albuminuria and renal lesion accompanied with dyslipidaemia and obesity in db/db diabetic mice. It is a new drug that exerts comprehensive protective effects on preventing DN progression.
Collapse
Affiliation(s)
- Qing Gao
- Research Institute of Nephrology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
273
|
Aberrant cytokines/chemokines production correlate with proteinuria in patients with overt diabetic nephropathy. Clin Chim Acta 2010; 411:700-4. [PMID: 20138168 DOI: 10.1016/j.cca.2010.01.036] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2009] [Revised: 12/25/2009] [Accepted: 01/28/2010] [Indexed: 12/27/2022]
|
274
|
Nishikawa T, Matsuzawa Y, Suematsu S, Saito J, Omura M, Kino T. Effect of atorvastatin on aldosterone production induced by glucose, LDL or angiotensin II in human renal mesangial cells. ARZNEIMITTEL-FORSCHUNG 2010; 60:445-51. [PMID: 20712135 PMCID: PMC2941820 DOI: 10.1055/s-0031-1296310] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Nephropathy is a major complication of diabetes mellitus, thus development of rational therapeutic means is critical for improving public health. It was previously reported that human mesangial cells locally produced aldosterone, a steroid hormone that plays an important role in the development of diabetic nephropathy. The present experiments clarified the effect of glucose, LDL and angiotensin II, the molecules frequently elevated in patients with diabetic nephropathy, on aldosterone production in human primary mesangial cells. These cells expressed the CYP11B2 mRNA, a rate-limiting enzyme in the aldosterone biosynthesis. LDL and angiotensin II stimulated CYP11B2 mRNA expression in these cells, while a high concentration of glucose, angiotensin II and/or LDL increased aldosterone production. Importantly, atorvastatin (CAS 134523-03-8), an HMG-CoA (3-hydroxy-3-methylglutaryl-coenzyme A) reductase inhibitor, strongly suppressed their effects on aldosterone production. Atorvastatin also suppressed positive effects of these compounds on the mRNA expression of the angiotensin II receptor type 1, thus atorvastatin exerted its negative effect in part through changing expression of this receptor. Since elevated levels of glucose and LDL, and increased action of the renin-angiotensin-aldosterone system is known to participate in the progression of diabetic nephropathy, it is speculated that the mesangial endocrine system that produces aldosterone locally is a promising therapeutic target for diabetic nephropathy where HMG-CoA reductase inhibitors provide a beneficial effect.
Collapse
Affiliation(s)
- Tetsuo Nishikawa
- Department of Medicine, Yokohama Rosai Hospital, Yokohama City, Kanagawa, Japan.
| | | | | | | | | | | |
Collapse
|
275
|
Zhu WW, Chen HP, Ge YC, Xie HL, Zeng CH, Li LS, Liu ZH. Ultrastructural changes in the glomerular filtration barrier and occurrence of proteinuria in Chinese patients with type 2 diabetic nephropathy. Diabetes Res Clin Pract 2009; 86:199-207. [PMID: 19815303 DOI: 10.1016/j.diabres.2009.09.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2009] [Revised: 08/25/2009] [Accepted: 09/08/2009] [Indexed: 02/07/2023]
Abstract
AIM Diabetic nephropathy (DN) is one of the most important causes of end stage renal disease in the world. Its hallmark is proteinuria. Therefore, we set out to clarify the structural changes that occur in the glomerular filtration barrier in Chinese patients with true type 2 diabetic nephropathy, and to examine the relationship between these structural changes and proteinuria. METHODS 42 Chinese patients with true T2DN were divided into three groups according to urinary protein excretion. Glomerular volume, endothelial cell density, endothelial cell number, glomerular basement membrane (GBM) width, podocyte density, podocyte number and foot process width were evaluated using light and electron microscopic morphometry. RESULT Glomerular volume and endothelial cell number were increased in diabetic patients, but there was no difference between patients with respect to the degree of proteinuria. As proteinuria progressed, endothelial cell density remained unchanged, while the glomerular basement membrane (GBM) and podocyte foot process width increased, podocyte density and number decreased. CONCLUSIONS Podocyte and GBM change more obviously during the development of proteinuria. Besides, proteinuria was inversely related to podocyte density, and directly related to GBM and glomerular volume.
Collapse
Affiliation(s)
- Wei-wei Zhu
- Research Institute of Nephrology, Jingling Hospital, Nanjing University School of Medicine, Nanjing, China
| | | | | | | | | | | | | |
Collapse
|
276
|
Nishiyama A, Kobori H, Konishi Y, Morikawa T, Maeda I, Okumura M, Kishida M, Hamada M, Nagai Y, Nakagawa T, Ohashi N, Nakano D, Hitomi H, Imanishi M. Mineralocorticoid receptor blockade enhances the antiproteinuric effect of an angiotensin II blocker through inhibiting podocyte injury in type 2 diabetic rats. J Pharmacol Exp Ther 2009; 332:1072-80. [PMID: 19940106 DOI: 10.1124/jpet.109.158113] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Treatment with angiotensin II type 1 receptor blockers (ARBs) is the first-line therapy for hypertensive patients with diabetic nephropathy. However, emerging clinical evidence indicates that mineralocorticoid receptor (MR) blockers have blood pressure-independent antiproteinuric effects. We sought to determine whether treatment with an MR blocker, eplerenone, enhances the effects of an ARB, telmisartan, on podocyte injury and proteinuria in type 2 diabetic Otsuka-Long-Evans-Tokushima-Fatty (OLETF) rats. From 20 to 50 weeks old, diabetic OLETF rats showed higher systolic blood pressure (SBP) and urinary protein excretion (U(protein)V) than nondiabetic control Long-Evans-Tokushima-Otsuka rats. At 50 weeks old, OLETF rats also showed glomerular sclerosis and podocyte injury, whereas nephrin and podocin mRNA levels in isolated glomeruli were significantly decreased. Treatment with telmisartan (3 mg/kg/day p.o.) decreased SBP and U(protein)V, increased nephrin and podocin mRNA levels, and attenuated glomerular sclerosis and podocyte injury. Eplerenone (100 mg/kg/day p.o.) did not alter SBP but elicited similar changes in renal parameters. However, greater reductions in U(protein)V and podocyte injury and greater increases in nephrin and podocin mRNA levels were observed in the combination treatment group. Hydralazine (25 mg/kg/day p.o.) decreased SBP but did not alter any renal parameters. These data indicate that MR blockade enhances the SBP-independent antiproteinuric effect of an ARB through inhibiting podocyte injury in type 2 diabetic rats.
Collapse
Affiliation(s)
- Akira Nishiyama
- Department of Pharmacology, Kagawa University Medical School, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
277
|
Boor P, Celec P, Behuliak M, Grancic P, Kebis A, Kukan M, Pronayová N, Liptaj T, Ostendorf T, Sebeková K. Regular moderate exercise reduces advanced glycation and ameliorates early diabetic nephropathy in obese Zucker rats. Metabolism 2009; 58:1669-77. [PMID: 19608208 DOI: 10.1016/j.metabol.2009.05.025] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2009] [Revised: 05/29/2009] [Accepted: 05/29/2009] [Indexed: 10/20/2022]
Abstract
Advanced glycation end products (AGEs) play a key role in the pathogenesis of diabetes and its complications, including the diabetic nephropathy. The renoprotective effects of exercise are well known; however, the mechanisms remain elusive. Here we examined whether a regular moderate exercise in obese Zucker rats (OZR), a model of diabetes- and obesity-associated nephropathy, will affect the development of early renal injury in OZR possibly via alteration of AGEs formation. The OZR were left without exercise (sedentary) or subjected to 10 weeks intermittent treadmill running of moderate intensity. Compared with sedentary OZR, kidneys of running OZR had significantly less glomerular mesangial expansion and tubulointerstitial fibrosis. Running OZR had significantly lower plasma AGEs-associated fluorescence and N(epsilon)-carboxymethyllysine. Correspondingly, renal AGEs and N(epsilon)-carboxymethyllysine content were lower in running OZR. Systemically, exercise increased aerobic metabolism, as apparent from urinary metabolite profiling. No differences in plasma glucose, insulin, or lipid profile were found between the 2 groups. Apart from lower advanced oxidation protein products (a marker of myeloperoxidase activity), no other marker of inflammation was altered by exercise, either systemically or locally in kidneys. No indication of changed oxidative status was revealed between the groups. Exercise in OZR decreased advanced glycation. This might represent the early event of exercise-induced renoprotection in diabetic nephropathy in OZR. If confirmed in clinical studies, regular moderate exercise could represent an easy and effective nonpharmacologic approach to reduce advanced glycation.
Collapse
Affiliation(s)
- Peter Boor
- Department of Clinical and Experimental Pharmacotherapy, Slovak Medical University, 833 03 Bratislava, Slovakia.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
278
|
Wang XX, Jiang T, Shen Y, Adorini L, Pruzanski M, Gonzalez FJ, Scherzer P, Lewis L, Miyazaki-Anzai S, Levi M. The farnesoid X receptor modulates renal lipid metabolism and diet-induced renal inflammation, fibrosis, and proteinuria. Am J Physiol Renal Physiol 2009; 297:F1587-96. [PMID: 19776172 DOI: 10.1152/ajprenal.00404.2009] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Diet-induced obesity is associated with proteinuria and glomerular disease in humans and rodents. We have shown that in mice fed a high-fat diet, increased renal expression of the transcriptional factor sterol-regulatory element binding protein-1 (SREBP-1) plays a critical role in renal lipid accumulation and increases the activity of proinflammatory cytokines and profibrotic growth factors. In the current study, we have determined a key role of the farnesoid X receptor (FXR) in modulating renal SREBP-1 activity, glomerular lesions, and proteinuria. We found that feeding a Western-style diet to DBA/2J mice results in proteinuria, podocyte loss, mesangial expansion, renal lipid accumulation, and increased expression of proinflammatory factors, oxidative stress, and profibrotic growth factors. Treatment of these mice with the highly selective and potent FXR-activating ligand 6-alpha-ethyl-chenodeoxycholic acid (INT-747) ameliorates triglyceride accumulation by modulating fatty acid synthesis and oxidation, improves proteinuria, prevents podocyte loss, mesangial expansion, accumulation of extracellular matrix proteins, and increased expression of profibrotic growth factors and fibrosis markers, and modulates inflammation and oxidative stress. Our results therefore indicate that FXR activation could represent an effective therapy for treatment of abnormal renal lipid metabolism with associated inflammation, oxidative stress, and kidney pathology in patients affected by obesity.
Collapse
Affiliation(s)
- Xiaoxin X Wang
- Department of Medicine, University of Colorado Denver, and Veterans Affairs Medical Center, Aurora, Colorado, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
279
|
Thrailkill KM, Nimmo T, Bunn RC, Cockrell GE, Moreau CS, Mackintosh S, Edmondson RD, Fowlkes JL. Microalbuminuria in type 1 diabetes is associated with enhanced excretion of the endocytic multiligand receptors megalin and cubilin. Diabetes Care 2009; 32:1266-8. [PMID: 19366958 PMCID: PMC2699744 DOI: 10.2337/dc09-0112] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Proteinuria is the hallmark of diabetic nephropathy; yet, glomerular histology does not fully explain mechanisms contributing to proteinuria. Our objective was to identify proteins in the urine of individuals with type 1 diabetes and microalbuminuria that might implicate a mechanistic pathway operative in proteinuria. RESEARCH DESIGN AND METHODS Using a GeLC/MS platform proteomics approach, we compared the urine proteome from 12 healthy nondiabetic individuals, 12 subjects with type 1 diabetes yet normal urinary albumin excretion rates, and 12 subjects with type 1 diabetes and microalbuminuria (type 1 diabetes + microalbuminuria). RESULTS The abundance of megalin and cubilin, two multiligand receptors expressed in kidney proximal tubule cells and involved with the reuptake of filtered albumin and megalin/cubilin ligands, was significantly increased in type 1 diabetes + microalbuminuria urine, compared with both nonalbuminuric groups. CONCLUSIONS Aberrant shedding of megalin and cubilin could contribute to albuminuria in diabetes and to deficiency states of important vitamins and hormones.
Collapse
Affiliation(s)
- Kathryn M Thrailkill
- Department of Pediatrics, University of Arkansas for Medical Sciences and Arkansas Children's Hospital Research Institute, Little Rock, Arkansas, USA.
| | | | | | | | | | | | | | | |
Collapse
|
280
|
Ninomiya T, Perkovic V, de Galan BE, Zoungas S, Pillai A, Jardine M, Patel A, Cass A, Neal B, Poulter N, Mogensen CE, Cooper M, Marre M, Williams B, Hamet P, Mancia G, Woodward M, Macmahon S, Chalmers J. Albuminuria and kidney function independently predict cardiovascular and renal outcomes in diabetes. J Am Soc Nephrol 2009; 20:1813-21. [PMID: 19443635 DOI: 10.1681/asn.2008121270] [Citation(s) in RCA: 669] [Impact Index Per Article: 44.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
There are limited data regarding whether albuminuria and reduced estimated GFR (eGFR) are separate and independent risk factors for cardiovascular and renal events among individuals with type 2 diabetes. The Action in Diabetes and Vascular disease: preterAx and diamicroN-MR Controlled Evaluation (ADVANCE) study examined the effects of routine BP lowering on adverse outcomes in type 2 diabetes. We investigated the effects of urinary albumin-to-creatinine ratio (UACR) and eGFR on the risk for cardiovascular and renal events in 10,640 patients with available data. During an average 4.3-yr follow-up, 938 (8.8%) patients experienced a cardiovascular event and 107 (1.0%) experienced a renal event. The multivariable-adjusted hazard ratio for cardiovascular events was 2.48 (95% confidence interval 1.74 to 3.52) for every 10-fold increase in baseline UACR and 2.20 (95% confidence interval 1.09 to 4.43) for every halving of baseline eGFR, after adjustment for regression dilution. There was no evidence of interaction between the effects of higher UACR and lower eGFR. Patients with both UACR >300 mg/g and eGFR <60 ml/min per 1.73 m(2) at baseline had a 3.2-fold higher risk for cardiovascular events and a 22.2-fold higher risk for renal events, compared with patients with neither of these risk factors. In conclusion, high albuminuria and low eGFR are independent risk factors for cardiovascular and renal events among patients with type 2 diabetes.
Collapse
Affiliation(s)
- Toshiharu Ninomiya
- George Institute for International Health, University of Sydney, Sydney, NSW, Australia
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
281
|
Górriz Teruel J. ¿Cómo realizar la búsqueda de enfermedad renal en pacientes con enfermedad cardiovascular? Med Clin (Barc) 2009; 132 Suppl 1:6-12. [DOI: 10.1016/s0025-7753(09)70956-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
282
|
Meier M, Menne J, Haller H. Targeting the protein kinase C family in the diabetic kidney: lessons from analysis of mutant mice. Diabetologia 2009; 52:765-75. [PMID: 19238353 DOI: 10.1007/s00125-009-1278-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2008] [Accepted: 01/07/2009] [Indexed: 10/21/2022]
Abstract
The protein kinase C (PKC) superfamily comprises proteins that are activated in response to various pathogenic stimuli in the diabetic state. Hyperglycaemia is the predominant stimulus that induces the activation of distinct PKC isoforms within a cell, each mediating specific functions, probably through differential subcellular localisation. The contribution of individual PKC isoforms can be directly addressed in vivo using innovative PKC-isoform-specific knockout (KO) mouse models, which are providing key insights into the physiological function of PKC isoform diversity in the development of diabetic nephropathy. Such studies can be a valuable complementary approach to more commonly used pharmacological analyses using agents such as ruboxistaurin mesylate (Arxxant, LY333531), which is claimed to specifically inhibit the PKC-beta-isoform. As expected given the multiple and specific properties of the isoforms in vitro, deletion of different PKC isoform signalling pathways leads to distinct phenotypes in mice. Notably, KOs of the individual PKCs assigned specific non-redundant biological functions to each isoform, which were not compensated for by the others. Thus, PKC isoform specificity and cellular diversity seem to be responsible for the divergent outcomes leading to albuminuria and/or renal fibrosis according to studies on the streptozotocin-induced mouse model of diabetes. This review discusses the role of individual PKC isoforms in diabetic nephropathy and their potential therapeutic implications. Defining and targeting mediators of increased intracellular activation in the diabetic microvasculature will have important clinical and therapeutic benefits and help in the design of novel effective therapies in the near future.
Collapse
Affiliation(s)
- M Meier
- Department of Nephrology, Hannover Medical School, Hannover, Germany.
| | | | | |
Collapse
|
283
|
Gupta R, Beaudet L, Moore J, Mehta T. Treatment of sarcoid granulomatous interstitial nephritis with adalimumab. NDT Plus 2009; 2:139-42. [PMID: 25949311 PMCID: PMC4421347 DOI: 10.1093/ndtplus/sfn200] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2008] [Accepted: 12/02/2008] [Indexed: 11/16/2022] Open
Abstract
Sarcoidosis is a systemic disease with multiorgan involvement which can cause renal failure through several different mechanisms. Granulomatous interstitial nephritis is an important albeit less frequent cause of clinically significant renal disease. Herein, we present the case of a 46 year old woman with a history of sarcoidosis whom we evaluated for rapidly worsening kidney function and proteinuria. Renal biopsy revealed granulomatous interstitial nephritis. After therapy with adalimumab, her renal function improved with a significant reduction in proteinuria. Repeat kidney biopsy showed resolution of renal granulomata. To our knowledge, this is the first report of successful treatment of granulomatous interstitial nephritis with adalimumab.
Collapse
Affiliation(s)
| | - Lisa Beaudet
- Department of Pathology, Washington Hospital Center, Washington, DC , USA
| | | | | |
Collapse
|
284
|
Sudo H, Hirata M, Kanada H, Yorozu K, Tashiro Y, Serizawa KI, Yogo K, Kataoka M, Moriguchi Y, Ishizuka N. Nicorandil Improves Glomerular Injury in Rats With Mesangioproliferative Glomerulonephritis via Inhibition of Proproliferative and Profibrotic Growth Factors. J Pharmacol Sci 2009; 111:53-9. [DOI: 10.1254/jphs.09072fp] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
|
285
|
Abstract
The classic mechanism to explain albumin excretion in diabetes has been permeability defects in the glomerular filter. However, a new concept has emerged that albuminuria can be explained by the two major pathways the proximal tubular cell uses to process filtered albumin. Specifically, albumin permeability through the glomerular filter is only governed by size selectivity. Most of the filtered albumin is retrieved by the proximal tubular cell and returned to the peritubular blood supply. Albuminuria in the nephrotic range would arise from retrieval pathway dysfunction. The small quantities of filtered albumin that are not retrieved undergo obligatory lysosomal degradation before urinary excretion as small peptide fragments. This pathway is sensitive to metabolic factors responsible for hypertrophy and fibrosis, particularly molecules such as angiotensin II and transforming growth factor-beta1, whose production is stimulated by hyperglycemic environments. Dysfunction in this degradation pathway may lead to albuminuria below the nephrotic range.
Collapse
Affiliation(s)
- Wayne D Comper
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia.
| | | |
Collapse
|
286
|
|