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Liu SJ, Cao YL, Zhang C. Hirudin in the Treatment of Chronic Kidney Disease. Molecules 2024; 29:1029. [PMID: 38474541 DOI: 10.3390/molecules29051029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 02/13/2024] [Accepted: 02/26/2024] [Indexed: 03/14/2024] Open
Abstract
Chronic kidney disease (CKD) is a common public health concern. The global burden of CKD is increasing due to the high morbidity and mortality associated with it, indicating the shortcomings of therapeutic drugs at present. Renal fibrosis is the common pathology of CKD, which is characterized by glomerulosclerosis, renal tubular atrophy, and renal interstitial fibrosis. Natural hirudin is an active ingredient extracted from Hirudo medicinalis, which has been found to be the strongest natural specific inhibitor of thrombin. Evidence based on pharmacological data has shown that hirudin has important protective effects in CKD against diabetic nephrology, nephrotic syndrome, and renal interstitial fibrosis. The mechanisms of hirudin in treating CKD are mainly related to inhibiting the inflammatory response, preventing apoptosis of intrinsic renal cells, and inhibiting the interactions between thrombin and protease-activated receptors. In this review, we summarize the function and beneficial properties of hirudin for the treatment of CKD, and its underlying mechanisms.
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Affiliation(s)
- Sai-Ji Liu
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yi-Ling Cao
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Chun Zhang
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
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Manera M, Casciano F, Giari L. Ultrastructural Alterations of the Glomerular Filtration Barrier in Fish Experimentally Exposed to Perfluorooctanoic Acid. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:5253. [PMID: 37047869 PMCID: PMC10094651 DOI: 10.3390/ijerph20075253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/17/2023] [Accepted: 03/22/2023] [Indexed: 06/19/2023]
Abstract
Per- and polyfluoroalkyl substances can be referred to as the most critical group of contaminants of emerging concern. They can accumulate in high concentration in the kidney and are known to potentially affect its function. Nonetheless, there is a lack of knowledge about their morphopathological effect on the glomerular filtration barrier. Since previous research suggests perfluorooctanoic acid (PFOA) induces glomerular protein leakage, the glomerular filtration barrier of 30 carp from the same parental stock (10 unexposed; 10 exposed to 200 ng L-1 of PFOA; and 10 exposed to 2 mg L-1 of PFOA for 56 days) was screened for possible PFOA-induced ultrastructural lesions in order to shed light on the related pathophysiology. PFOA exposure affected the glomerular filtration barrier in carp experimentally exposed to 2 mg L-1, showing ultrastructural alterations compatible with glomerulonephrosis: podocyte effacement, reduction of filtration slits and filtration slit diaphragms, basement membrane disarrangement, and occurrence of proteinaceous material in the urinary space. The results of the present research confirm the glomerular origin of the PFOA-induced protein leakage and can contribute to the mechanistic comprehension of PFOA's impact on renal function and to the assessment of the exposure effect of environmental pollutants on animals and humans, according to the One Health approach.
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Affiliation(s)
- Maurizio Manera
- Department of Biosciences, Food and Environmental Technologies, University of Teramo, St. R. Balzarini 1, 64100 Teramo, Italy
| | - Fabio Casciano
- Department of Translational Medicine and LTTA Centre, University of Ferrara, St. Fossato di Mortara 70, 44121 Ferrara, Italy
| | - Luisa Giari
- Department of Environmental and Prevention Sciences, University of Ferrara, St. Borsari 46, 44121 Ferrara, Italy
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Xu Z, Yue P, Feng JJ. Poroelastic modelling reveals the cooperation between two mechanisms for albuminuria. J R Soc Interface 2023; 20:20220634. [PMID: 36628531 PMCID: PMC9832287 DOI: 10.1098/rsif.2022.0634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 12/08/2022] [Indexed: 01/12/2023] Open
Abstract
Albuminuria occurs when albumin leaks abnormally into the urine. Its mechanism remains unclear. A gel-compression hypothesis attributes the glomerular barrier to compression of the glomerular basement membrane (GBM) as a gel layer. Loss of podocyte foot processes would allow the gel layer to expand circumferentially, enlarge its pores and leak albumin into the urine. To test this hypothesis, we develop a poroelastic model of the GBM. It predicts GBM compression in healthy glomerulus and GBM expansion in the diseased state, essentially confirming the hypothesis. However, by itself, the gel compression and expansion mechanism fails to account for two features of albuminuria: the reduction in filtration flux and the thickening of the GBM. A second mechanism, the constriction of flow area at the slit diaphragm downstream of the GBM, must be included. The cooperation between the two mechanisms produces the amount of increase in GBM porosity expected in vivo in a mutant mouse model, and also captures the two in vivo features of reduced filtration flux and increased GBM thickness. Finally, the model supports the idea that in the healthy glomerulus, gel compression may help maintain a roughly constant filtration flux under varying filtration pressure.
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Affiliation(s)
- Zelai Xu
- Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z2
| | - Pengtao Yue
- Department of Mathematics, Virginia Tech, Blacksburg, VA 24061, USA
| | - James J. Feng
- Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z2
- Department of Mathematics, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z2
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Feng Y, Li M, Wang Y, Yang M, Shi G, Yin D, Xuan Z, Xu F. Activation of TRPC6 by AngⅡ Induces Podocyte Injury and Participates in Proteinuria of Nephrotic Syndrome. Front Pharmacol 2022; 13:915153. [PMID: 35991898 PMCID: PMC9382118 DOI: 10.3389/fphar.2022.915153] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 05/18/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Nephrotic syndrome (NS) is a common glomerular disease, and podocyte injury is the character of primary NS, usually caused by minimal change disease and membranous nephropathy. Podocytopathy is primarily associated with glomerular proteinuria. Losartan, an angiotensin receptor blocker (ARB), is commonly used in the treatment of NS, and the AngiotensinⅡ (AngⅡ)–transient receptor potential ion channel 6 (TRPC6) axis has been reported to act on podocytes to regulate proteinuria in NS. Therefore, the purpose of this study was to explore the relationship in between AngⅡ–TRPC6, podocyte injury, and proteinuria based on the adriamycin (ADR) NS rat model.Method: All male rats were divided into three groups: control group, model group, and ARB group. The rats in the model group were induced by ADR, and the rats in the ARB group received losartan after induction of renal injury for 4 weeks. The changes in parameters related to renal dysfunction, and glomerular and podocyte structural damage, such as AngⅡ, AngⅡ type I receptor (AT1R), TRPC6, CaN, Caspase-3, Nephrin, and Podocin, were analyzed. Furthermore, the kidneys were isolated for study via transmission electron microscopy (TEM), immunohistochemistry, and western blot (WB) after the rats were sacrificed. In vitro, immortalized mouse MPC5 podocytes were used to investigate the regulatory effect of flufenamic acid (Flu) and SAR7334 (SAR) on the AngⅡ-TRPC6 signaling axis. Flow cytometry and WB were conducted to determine the relationship between podocyte injury and AngⅡ-TRPC6.Results:In vivo results showed that NS rats developed massive albuminuria and abnormal renal function, accompanied by abnormally increased levels of AngⅡ, TRPC6, AT1R, and CaN and a decreased expression of actin molecules in podocytes, extensive fusion of foot processes (FP), loss of glomerular structural integrity, collapse of podocyte structure, and skeletal reorganization. In vitro experiments indicated that both AngⅡ and Flu (the specific agonist of TRPC6) stimulated the expressions of TRPC6, AT1R, and Caspase-3 in podocytes. The AngⅡ receptor–blocker losartan and TRPC6-specific inhibitor SAR blocked the overexpression of the aforementioned proteins. In addition, SAR also attenuated the degradation of podocyte structural proteins and inhibited the fluorescence intensity of intracellular calcium (Ca2+) and cell apoptosis.Conclusion: The involvement of AngⅡ in the occurrence of NS proteinuria may be related to podocyte injury induced by activated TRPC6.
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Affiliation(s)
- Ye Feng
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, China
| | - Manman Li
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, China
| | - Yunlai Wang
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, China
| | - Mo Yang
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, China
| | - Gaoxiang Shi
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, China
| | - Dengke Yin
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, China
| | - Zihua Xuan
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, China
- *Correspondence: Zihua Xuan, ; Fan Xu,
| | - Fan Xu
- Anhui Province Key Laboratory of Chinese Medicinal Formula, Hefei, China
- *Correspondence: Zihua Xuan, ; Fan Xu,
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Lee YH, Song GG. Comparative Efficacy and Safety of Tacrolimus, Cyclosporin A, Mycophenolate Mofetil, Cyclophosphamide, and Corticosteroids as Induction Therapy for Membranous Lupus Nephritis: A Network Meta-Analysis. Pharmacology 2022; 107:439-445. [PMID: 35609529 DOI: 10.1159/000525066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 04/29/2022] [Indexed: 11/19/2022]
Abstract
BACKGROUND There were limited data on randomized controlled trials (RCTs) evaluating the effectiveness and safety of tacrolimus (TAC), cyclosporin A (CSA), mycophenolate mofetil (MMF), cyclophosphamide (CYC), and corticosteroids as induction agents in membranous lupus nephritis, and they were inconclusive. OBJECTIVES This study aimed to assess the relative efficacy and safety TAC, CSA, MMF, CYC, and corticosteroids as induction therapy for membranous lupus nephritis. METHOD RCTs examining the efficacy and safety of TAC, CSA, MMF, CYC, and corticosteroids as induction therapy in patients with membranous lupus nephritis were included. We performed a Bayesian random-effects network meta-analysis to combine direct and indirect evidence from the RCTs. RESULTS Five RCTs comprising 126 patients met the inclusion criteria. TAC and CSA showed a trend toward a higher overall response rate (complete remission plus partial remission) than MMF and CYC. Similarly, MMF and CYC showed a trend toward a higher overall response than corticosteroids. Ranking probability based on the surface under the cumulative ranking curve indicated that TAC had the highest probability of being the best treatment for achieving the overall response, followed by CSA, MMF, CYC, and corticosteroids. In terms of safety, corticosteroids showed the highest probability of decreasing the risk of infections, followed by CSA, CYC, MMF, and TAC. CONCLUSIONS TAC and CSA were the most efficacious induction treatments for patients with membranous lupus nephritis, and corticosteroids had the highest probability of decreasing the risk of infections.
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Affiliation(s)
- Young Ho Lee
- Division of Rheumatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea
| | - Gwan Gyu Song
- Division of Rheumatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea
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Long C, Lin Q, Mo J, Xiao Y, Xie Y. Hirudin attenuates puromycin aminonucleoside‐induced glomerular podocyte injury by inhibiting MAPK‐mediated endoplasmic reticulum stress. Drug Dev Res 2022; 83:1047-1056. [PMID: 35277865 DOI: 10.1002/ddr.21932] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/13/2022] [Accepted: 02/22/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Chunli Long
- College of Basic Medicine Guangxi University of Traditional Chinese Medicine Nanning China
| | - Qiang Lin
- Department of Nephrology The First Affiliated Hospital of Guangxi University of Traditional Chinese Medicine Nanning China
| | - Junlin Mo
- College of Graduate school Guangxi University of Traditional Chinese Medicine Nanning China
| | - Yangping Xiao
- College of Graduate school Guangxi University of Traditional Chinese Medicine Nanning China
| | - Yongxiang Xie
- Department of Nephrology The First Affiliated Hospital of Guangxi University of Traditional Chinese Medicine Nanning China
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Basgen JM, Wong JS, Ray J, Nicholas SB, Campbell KN. Podocyte Foot Process Effacement Precedes Albuminuria and Glomerular Hypertrophy in CD2-Associated Protein Deficient Mice. Front Med (Lausanne) 2021; 8:745319. [PMID: 34568396 PMCID: PMC8460869 DOI: 10.3389/fmed.2021.745319] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 08/20/2021] [Indexed: 12/15/2022] Open
Abstract
Background: Podocyte foot process effacement is a key histologic finding in proteinuric kidney disease. We previously showed that 3-week old CD2AP-deficient mice have significant proteinuria, glomerular hypertrophy and mesangial expansion. The goal of this study is to use morphometry to establish the temporal sequence of podocyte foot process effacement, glomerular volume expansion and albuminuria in Cd2ap−/− mice by measuring these parameters at the 2-week time point. Methods: Wild-type mice age 14 ± 1 days with the Cd2ap gene (WT, N = 5) and mice deficient for Cd2ap (Cd2ap KO, N = 5) were generated. Kidneys were harvested and fixed in 2.5% glutaraldehyde and processed for examination by light and electron microscopy. An average of 415.2 (range 268–716) grid points were counted for all the glomeruli, and quantification of glomerular volume from each kidney. Urine was collected the day prior to sacrifice for urine albumin-to-creatinine ratio (ACR) measurements. Results: There was no difference in albuminuria [median (range) mg/g] between WT [212.2 (177.6–388.4) mg/g] vs. Cd2ap KO mice [203.3 (164.7–910.2) mg/g], P = 0.89; or glomerular volume 68,307[10,931] vs. 66,844[13,022] μm3, p = 0.92. The volume densities of glomerular components of the podocyte, capillary lumen and mesangium were not different for the two groups, P = 0.14, 0.14 and 0.17 respectively. However, foot process width was increased in Cd2ap KO 1128[286] vs. WT [374 ± 42] nm, P = 0.02. Conclusion: Here we show that while 2-week old WT and Cd2ap KO mice have similar levels of albuminuria, glomerular and mesangial volume, Cd2ap KO mice have more extensive podocyte foot process effacement. The data suggests that podocyte injury is the initiating event leading to mesangial expansion and albuminuria in this model.
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Affiliation(s)
- John M Basgen
- Department of Research, Stereology and Morphometry Laboratory, Charles R. Drew University of Medicine and Science, Los Angeles, CA, United States
| | - Jenny S Wong
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Justina Ray
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Susanne B Nicholas
- Division of Nephrology, David Geffen School of Medicine at University of California, Los Angeles, CA, United States
| | - Kirk N Campbell
- Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
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The ratio and difference of urine protein-to-creatinine ratio and albumin-to-creatinine ratio facilitate risk prediction of all-cause mortality. Sci Rep 2021; 11:7851. [PMID: 33846379 PMCID: PMC8041921 DOI: 10.1038/s41598-021-86541-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 03/01/2021] [Indexed: 11/09/2022] Open
Abstract
The role of the difference and ratio of albuminuria (urine albumin-to-creatinine ratio, uACR) and proteinuria (urine protein-to-creatinine ratio, uPCR) has not been systematically evaluated with all-cause mortality. We retrospectively analyzed 2904 patients with concurrently measured uACR and uPCR from the same urine specimen in a tertiary hospital in Taiwan. The urinary albumin-to-protein ratio (uAPR) was derived by dividing uACR by uPCR, whereas urinary non-albumin protein (uNAP) was calculated by subtracting uACR from uPCR. Conventional severity categories of uACR and uPCR were also used to establish a concordance matrix and develop a corresponding risk matrix. The median age at enrollment was 58.6 years (interquartile range 45.4-70.8). During the 12,391 person-years of follow-up, 657 deaths occurred. For each doubling increase in uPCR, uACR, and uNAP, the adjusted hazard ratios (aHRs) of all-cause mortality were 1.29 (95% confidence interval [CI] 1.24-1.35), 1.12 (1.09-1.16), and 1.41 (1.34-1.49), respectively. For each 10% increase in uAPR, it was 1.02 (95% CI 0.98-1.06). The linear dose-response association with all-cause mortality was only observed with uPCR and uNAP. The 3 × 3 risk matrices revealed that patients with severe proteinuria and normal albuminuria had the highest risk of all-cause mortality (aHR 5.25, 95% CI 1.88, 14.63). uNAP significantly improved the discriminative performance compared to that of uPCR (c statistics: 0.834 vs. 0.828, p-value = 0.032). Our study findings advocate for simultaneous measurements of uPCR and uACR in daily practice to derive uAPR and uNAP, which can provide a better mortality prognostic assessment.
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Pereira BM, Thieme K, de Araújo L, Rodrigues AC. Lack of adiponectin in mice accelerates high-fat diet-induced progression of chronic kidney disease. Life Sci 2020; 257:118061. [DOI: 10.1016/j.lfs.2020.118061] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 06/27/2020] [Accepted: 07/05/2020] [Indexed: 12/11/2022]
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Chen Y, Wang Z, Li Q, Yu L, Zhu Y, Wang J, Sun S. oxLDL promotes podocyte migration by regulating CXCL16, ADAM10 and ACTN4. Mol Med Rep 2020; 22:1976-1984. [PMID: 32705248 PMCID: PMC7411416 DOI: 10.3892/mmr.2020.11292] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Accepted: 05/22/2020] [Indexed: 01/19/2023] Open
Abstract
Nephrotic syndrome (NS) is one of the most common causes of chronic kidney disease in the pediatric population. Hyperlipidemia is one of the main features of NS. The present study investigated the role of CXC motif chemokine ligand 16 (CXCL16) and ADAM metallopeptidase domain 10 (ADAM10) in oxidized low-density lipoprotein (oxLDL)-stimualted podocytes and the underlying mechanisms. CXCL16 and ADAM10 expression levels in oxLDL-treated podocytes were measured via reverse transcription-quantitative PCR and western blotting. Cell migration assays were conducted to assess the migration of oxLDL-treated podocytes. CXCL16 or ADAM10 overexpression and knockdown assays were conducted. The results indicated that oxLDL stimulation increased ADAM10 and CXCL16 expression levels, and enhanced podocyte migration compared with the control group. Moreover, CXCL16 and ADAM10 overexpression significantly increased podocyte migration and the expression of actinin-α4 (ACTN4) compared with the control groups. By contrast, CXCL16 and ADAM10 knockdown significantly reduced podocyte migration and the expression of ACTN4 compared with the control groups. The results suggested that oxLDL promoted podocyte migration by regulating CXCL16 and ADAM10 expression, as well as by modulating the actin cytoskeleton. Therefore, CXCL16 and ADAM10 may serve as novel therapeutic targets for primary nephrotic syndrome in children.
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Affiliation(s)
- Yuan Chen
- Department of Pediatrics, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250021, P.R. China
| | - Zhiyi Wang
- Department of Hepatobiliary Surgery, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, P.R. China
| | - Qian Li
- Department of Pediatrics, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, P.R. China
| | - Lichun Yu
- Department of Pediatrics, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, P.R. China
| | - Yanji Zhu
- Department of Pediatrics, People's Hospital of Rizhao, Rizhao, Shandong 276800, P.R. China
| | - Jing Wang
- Department of Pediatrics, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, P.R. China
| | - Shuzhen Sun
- Department of Pediatrics, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250021, P.R. China
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Davis KL, Burnum AL, Beck JA, Kirejczyk SGM, Miller MA, Sola MF, Brown CA. Diagnosis of Collagen Type III Glomerulopathy Using Picrosirius Red and PASH/Masson's Trichrome Stain. Vet Pathol 2020; 57:675-680. [PMID: 32880237 DOI: 10.1177/0300985820934111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Canine collagen type III glomerulopathy (Col3GP) is a rare juvenile nephropathy in which irregular type III collagen fibrils and fibronectin accumulate in glomerular capillary walls and the mesangium. Necropsy findings were reviewed from 5 puppies diagnosed with Col3GP at 6 to 18 weeks of age. Histologically, with hematoxylin and eosin stain, the glomerular capillary walls and mesangium were diffusely and globally expanded by homogeneous pale eosinophilic material. Ultrastructurally, the subendothelial zone and mesangium were expanded by fibronectin and cross-banded collagen type III fibrils, diagnostic of Col3GP. Two additional stains were employed to identify the material within glomeruli as fibrillar collagen using light microscopy. In all 5 cases, the material was red with picrosirius red and birefringent under polarized light, and was blue with periodic acid-Schiff/hematoxylin/trichrome (PASH/TRI), thereby identifying it as fibrillar collagen. Based on these unique staining characteristics with picrosirius red and PASH/TRI, Col3GP may be reliably diagnosed with light microscopy alone.
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Affiliation(s)
- Katelin L Davis
- 311308Purdue University, West Lafayette, IN, USA.,National Cancer Institute, Comparative Biomedical Scientist Training Program, Bethesda, MD, USA
| | | | - Jessica A Beck
- 311308Purdue University, West Lafayette, IN, USA.,National Cancer Institute, Comparative Biomedical Scientist Training Program, Bethesda, MD, USA
| | | | | | - Mario F Sola
- 311308Purdue University, West Lafayette, IN, USA
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Fagbohun OF, Awoniran PO, Babalola OO, Agboola FK, Msagati TAM. Changes in the biochemical, hematological and histopathological parameters in STZ-Induced diabetic rats and the ameliorative effect of Kigelia africana fruit extract. Heliyon 2020; 6:e03989. [PMID: 32462092 PMCID: PMC7243140 DOI: 10.1016/j.heliyon.2020.e03989] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 04/01/2020] [Accepted: 04/12/2020] [Indexed: 02/07/2023] Open
Abstract
Background Biochemical, hematological and histological changes are major observable clinical and pathological factors associated with Diabetes mellitus. Derangement in the levels of these parameters increases the risk of the development of complications. In another hand, gastrointestinal intolerance due to the development of lactic acidosis on the gastrointestinal tract and the intestinal microbiome is the toxic side effect of various synthetic antidiabetic agents. The use of Kigelia africana fruit extract for the treatment of diabetes has been scientifically validated. This study therefore aimed at investigating changes in the biochemical, hematological and histological parameters as well as the determination of the functional groups present in the hexane fraction of the fruit. Methods The fruits were extracted with ethanol and partitioned with n-hexane to obtain the hexane fraction. Diabetic rats induced with streptozotocin (STZ) were divided into 5 groups of 5 animals each and treated with 100, 200 and 400 mg/kg body weight (BW) hexane fraction alongside reference standard; glibenclamide. Fasting blood glucose levels and their body weights were monitored weekly. Animals were sacrificed at the end of 28-day treatment. Blood, liver, and kidney were collected for biochemical, hematological and histopathological analyses. Fourier transform infrared resonance (FTIR) spectroscopic analysis was carried out on the hexane fraction for functional group determination. Results The hexane fraction of K. africana fruit extract decreased fasting blood glucose (FBG) levels significantly with ameliorative effects on the hematological parameters such as packed cell volume (PCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and red blood cells (RBC) etc. There were significant regenerative differences in the biochemical activities as well as the renal cortex and midzone sections of the rat's kidney and liver when compared with untreated diabetic rats. The presence of polyphenolic functional groups via FTIR analysis suggested high antioxidant activities of the fruit extract. Conclusion The use of Kigelia africana fruit extracts protects against biochemical, hematological and histological changes that are injurious to diabetic patients. Therefore, Kigelia africana fruit is a good hepatic- and nephroprotective agent and has a hemato-protective ability.
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Affiliation(s)
- Oladapo F Fagbohun
- Department of Biomedical Engineering, First Technical University, Ibadan, Oyo State, Nigeria
| | - Paul O Awoniran
- Department of Anatomy and Cell Biology, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
| | - Olubunmi O Babalola
- Department of Biochemistry and Molecular Biology, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
| | - Femi K Agboola
- Department of Biochemistry and Molecular Biology, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
| | - Titus A M Msagati
- Nanotechnology and Water Sustainability Research Unit, College of Science Engineering and Technology, University of South Africa (UNISA), Florida Park, Johannesburg, South Africa
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13
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Ahmed HM, Morgan DS, Doudar NA, Naguib MS. High Serum Endothelin-1 Level is Associated with Poor Response to Steroid Therapy in Childhood-Onset Nephrotic Syndrome. SAUDI JOURNAL OF KIDNEY DISEASES AND TRANSPLANTATION 2020; 30:769-774. [PMID: 31464232 DOI: 10.4103/1319-2442.265451] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Nephrotic syndrome (NS) is one of the most common kidney diseases seen in children. It is a disorder characterized by severe proteinuria, hypoproteinemia, hyperlipidemia, and generalized edema resulting from alterations of permeability at the glomerular capillary wall. Endothelin-1 (ET1) has a central role in the pathogenesis of proteinuria and glomerulosclerosis and has a role in assessment of the clinical course of NS in children. This study aims to investigate the relationship between ET1 serum level and the response to steroid therapy in children with primary NS. Serum ET1 levels were evaluated in 55 children with NS. They were classified into two groups: 30 patients with steroid-sensitive NS (SSNS) and 25 patients with steroid-resistant NS (SRNS). The SSNS group was further divided into infrequent-relapsing NS (IFRNS) and steroid-dependent NS (SDNS), while the SRNS group was subdivided into two groups according to renal pathology. ET1 levels were significantly higher in the SRNS group (52.5 ± 45.8 pg/dL) compared to the SSNS group (18.3 ± 17 pg/dL) (P <0.001). Furthermore, ET1 levels were significantly higher in SDNS (54.3 ± 18.6) compared to IFRNS (11.9 ± 7.8, P = 0.001). There was no statistically significant difference in ET1 levels between minimal change disease group and focal segmental glomerulosclerosis group, (P = 0.28). Serum ET1 can be considered as a predictor for response to steroid therapy.
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Affiliation(s)
- Heba Mostafa Ahmed
- Department of Pediatrics, Faculty of Medicine, Beni-Suef University, Beni Suef, Egypt
| | - Dalia S Morgan
- Department of Pediatrics, Faculty of Medicine, Beni-Suef University, Beni Suef, Egypt
| | - Noha A Doudar
- Department of Clinical and Chemical Pathology, Faculty of Medicine, Beni-Suef University, Beni Suef, Egypt
| | - Mariam S Naguib
- Department of Pediatrics, Faculty of Medicine, Beni-Suef University, Beni Suef, Egypt
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14
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Pfister F, Amann K, Daniel C, Klewer M, Büttner A, Büttner-Herold M. Characteristic morphological changes in anti-VEGF therapy-induced glomerular microangiopathy. Histopathology 2018; 73:990-1001. [PMID: 30014486 DOI: 10.1111/his.13716] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 07/15/2018] [Indexed: 11/26/2022]
Abstract
AIMS Agents targeting vascular endothelial growth factor (VEGF) have increasingly been used for the treatment of advanced malignancies, and have been found to induce renal thrombotic microangiopathy (TMA) and proteinuria. However, histomorphological changes in human biopsies in this setting and the underlying mechanism are not yet fully understood. Therefore, we collected renal biopsy cases with a history of aVEGF therapy to review and compare morphological kidney changes in this context. METHODS AND RESULTS Renal biopsies of 15 patients who had received anti-VEGF (aVEGF) therapy evaluated between 2013 and 2017 at a single centre were morphologically characterised with light microscopy, electron microscopy, and immunohistochemistry (IgA, IgG, IgM, C1q, and C3), and compared with cases with acute TMA caused by atypical haemolytic-uraemic syndrome or hypertension. Morphological overlap with immune complex and cryoglobulinaemic membranoproliferative glomerulonephritis, diabetic glomerulopathy and pre-eclampsia-induced glomerulopathy are discussed. Segmental glomerular capillary microaneurysms and segmental hyalinosis were typical morphological features of aVEGF therapy-induced glomerular microangiopathy, whereas fibrin or platelet thrombi or fragmented erythrocytes were rarely found or were absent. aVEGF therapy-associated microangiopathy was diffusely distributed in the glomeruli, spared preglomerular vessels, and showed morphological characteristics of chronic TMA. In individual cases, aVEGF therapy-induced glomerular microangiopathy was accompanied by immune-complex glomerulonephritis. CONCLUSION aVEGF therapy-induced glomerular microangiopathy has a characteristic morphology and clinical presentation that helps to differentiate it from other causes of TMA. Awareness of these light microscopic findings allows identification of aVEGF therapy as a trigger of renal disease in critically ill cancer patients, and might therefore help in deciding on further therapy.
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Affiliation(s)
- Frederick Pfister
- Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Kerstin Amann
- Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Christoph Daniel
- Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Monika Klewer
- Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Anke Büttner
- School of Psychology, College of Life and Environmental Sciences, University of Birmingham, Birmingham, UK
| | - Maike Büttner-Herold
- Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
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15
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Tang KT, Tseng CH, Hsieh TY, Chen DY. Induction therapy for membranous lupus nephritis: a systematic review and network meta-analysis. Int J Rheum Dis 2018; 21:1163-1172. [PMID: 29879319 DOI: 10.1111/1756-185x.13321] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Kuo-Tung Tang
- Division of Allergy, Immunology and Rheumatology; Taichung Veterans General Hospital; Taichung Taiwan
| | - Chien-Hua Tseng
- Division of Pulmonary Medicine; Department of Internal Medicine; Shuang Ho Hospital; Taipei Medical University; Taipei Taiwan
- Institute of Epidemiology and Preventive Medicine; National Taiwan University; Taipei Taiwan
| | - Tsu-Yi Hsieh
- Division of Allergy, Immunology and Rheumatology; Taichung Veterans General Hospital; Taichung Taiwan
| | - Der-Yuan Chen
- Translational Medicine Laboratory; Rheumatic Diseases Research Center; China Medical University Hospital; Taichung Taiwan
- Rheumatology and Immunology Center; China Medical University Hospital; Taichung Taiwan
- School of Medicine; China Medical University; Taichung Taiwan
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16
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Tabatabaeifar M, Wlodkowski T, Simic I, Denc H, Mollet G, Weber S, Moyers JJ, Brühl B, Randles MJ, Lennon R, Antignac C, Schaefer F. An inducible mouse model of podocin-mutation-related nephrotic syndrome. PLoS One 2017; 12:e0186574. [PMID: 29049388 PMCID: PMC5648285 DOI: 10.1371/journal.pone.0186574] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 09/10/2017] [Indexed: 12/03/2022] Open
Abstract
Mutations in the NPHS2 gene, encoding podocin, cause hereditary nephrotic syndrome. The most common podocin mutation, R138Q, is associated with early disease onset and rapid progression to end-stage renal disease. Knock-in mice carrying a R140Q mutation, the mouse analogue of human R138Q, show developmental arrest of podocytes and lethal renal failure at neonatal age. Here we created a conditional podocin knock-in model named NPHS2R140Q/-, using a tamoxifen-inducible Cre recombinase, which permits to study the effects of the mutation in postnatal life. Within the first week of R140Q hemizygosity induction the animals developed proteinuria, which peaked after 4–5 weeks. Subsequently the animals developed progressive renal failure, with a median survival time of 12 (95% CI: 11–13) weeks. Foot process fusion was observed within one week, progressing to severe and global effacement in the course of the disease. The number of podocytes per glomerulus gradually diminished to 18% compared to healthy controls 12–16 weeks after induction. The fraction of segmentally sclerosed glomeruli was 25%, 85% and 97% at 2, 4 and 8 weeks, respectively. Severe tubulointerstitial fibrosis was present at later disease stage and was correlated quantitatively with the level of proteinuria at early disease stages. While R140Q podocin mRNA expression was elevated, protein abundance was reduced by more than 50% within one week following induction. Whereas miRNA21 expression persistently increased during the first 4 weeks, miRNA-193a expression peaked 2 weeks after induction. In conclusion, the inducible R140Q-podocin mouse model is an auspicious model of the most common genetic cause of human nephrotic syndrome, with a spontaneous disease course strongly reminiscent of the human disorder. This model constitutes a valuable tool to test the efficacy of novel pharmacological interventions aimed to improve podocyte function and viability and attenuate proteinuria, glomerulosclerosis and progressive renal failure.
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Affiliation(s)
- Mansoureh Tabatabaeifar
- Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
| | - Tanja Wlodkowski
- Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
| | - Ivana Simic
- Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
| | - Helga Denc
- Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
| | - Geraldine Mollet
- INSERM, U1163, Imagine Institute, Laboratory of Hereditary Kidney Diseases, Paris, France
- Paris Descartes-Sorbonne Paris Cité University, Paris, France
| | - Stefanie Weber
- Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, Philipps-University Marburg, Marburg, Germany
| | | | - Barbara Brühl
- Institute for Anatomy and Cell Biology, University of Heidelberg, Heidelberg, Germany
| | - Michael Joseph Randles
- Wellcome Trust Centre for Cell Matrix Research, University of Manchester, Manchester, United Kingdom
- Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Rachel Lennon
- Wellcome Trust Centre for Cell Matrix Research, University of Manchester, Manchester, United Kingdom
- Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Corinne Antignac
- INSERM, U1163, Imagine Institute, Laboratory of Hereditary Kidney Diseases, Paris, France
- Paris Descartes-Sorbonne Paris Cité University, Paris, France
- Department of Genetics, Necker Hospital, Assistance Publique—Hôpitaux de Paris, Paris, France
| | - Franz Schaefer
- Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
- * E-mail:
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17
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Ilatovskaya DV, Palygin O, Levchenko V, Endres BT, Staruschenko A. The Role of Angiotensin II in Glomerular Volume Dynamics and Podocyte Calcium Handling. Sci Rep 2017; 7:299. [PMID: 28331185 PMCID: PMC5428415 DOI: 10.1038/s41598-017-00406-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 02/27/2017] [Indexed: 02/03/2023] Open
Abstract
Podocytes are becoming a primary focus of research efforts due to their association with progressive glomeruli damage in disease states. Loss of podocytes can occur as a result of excessive intracellular calcium influx, and we have previously shown that angiotensin II (Ang II) via canonical transient receptor potential 6 (TRPC6) channels caused increased intracellular Ca2+ flux in podocytes. We showed here with patch-clamp electrophysiology that Ang II activates TRPC channels; then using confocal calcium imaging we demonstrated that Ang II-dependent stimulation of Ca2+ influx in the podocytes is precluded by blocking either AT1 or AT2 receptors (ATRs). Application of Ang(1-7) had no effect on intracellular calcium. Ang II-induced calcium flux was decreased upon inhibition of TRPC channels with SAR7334, SKF 96365, clemizole hydrochloride and La3+, but not ML204. Using a novel 3D whole-glomerulus imaging ex vivo assay, we revealed the involvement of both ATRs in controlling glomerular permeability; additionally, using specific inhibitors and activators of TRPC6, we showed that these channels are implicated in the regulation of glomerular volume dynamics. Therefore, we provide evidence demonstrating the critical role of Ang II/TRPC6 axis in the control of glomeruli function, which is likely important for the development of glomerular diseases.
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Affiliation(s)
- Daria V Ilatovskaya
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, 53226, USA
| | - Oleg Palygin
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, 53226, USA
| | - Vladislav Levchenko
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, 53226, USA
| | - Bradley T Endres
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, 53226, USA
| | - Alexander Staruschenko
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, 53226, USA.
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18
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Heinolainen K, Karaman S, D'Amico G, Tammela T, Sormunen R, Eklund L, Alitalo K, Zarkada G. VEGFR3 Modulates Vascular Permeability by Controlling VEGF/VEGFR2 Signaling. Circ Res 2017; 120:1414-1425. [PMID: 28298294 DOI: 10.1161/circresaha.116.310477] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/08/2017] [Accepted: 03/14/2017] [Indexed: 01/02/2023]
Abstract
RATIONALE Vascular endothelial growth factor (VEGF) is the main driver of angiogenesis and vascular permeability via VEGF receptor 2 (VEGFR2), whereas lymphangiogenesis signals are transduced by VEGFC/D via VEGFR3. VEGFR3 also regulates sprouting angiogenesis and blood vessel growth, but to what extent VEGFR3 signaling controls blood vessel permeability remains unknown. OBJECTIVE To investigate the role of VEGFR3 in the regulation of VEGF-induced vascular permeability. METHODS AND RESULTS Long-term global Vegfr3 gene deletion in adult mice resulted in increased fibrinogen deposition in lungs and kidneys, indicating enhanced vascular leakage at the steady state. Short-term deletion of Vegfr3 in blood vascular endothelial cells increased baseline leakage in various tissues, as well as in tumors, and exacerbated vascular permeability in response to VEGF, administered via intradermal adenoviral delivery or through systemic injection of recombinant protein. VEGFR3 gene silencing upregulated VEGFR2 protein levels and phosphorylation in cultured endothelial cells. Consistent with elevated VEGFR2 activity, vascular endothelial cadherin showed reduced localization at endothelial cell-cell junctions in postnatal retinas after Vegfr3 deletion, or after VEGFR3 silencing in cultured endothelial cells. Furthermore, concurrent deletion of Vegfr2 prevented VEGF-induced excessive vascular leakage in mice lacking Vegfr3. CONCLUSIONS VEGFR3 limits VEGFR2 expression and VEGF/VEGFR2 pathway activity in quiescent and angiogenic blood vascular endothelial cells, thereby preventing excessive vascular permeability.
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Affiliation(s)
- Krista Heinolainen
- From the Wihuri Research Institute and Translational Cancer Biology Research Program, Biomedicum Helsinki, University of Helsinki, Finland (K.H., S.K., G.D'A., T.T., K.A., G.Z.); Biocenter Oulu and Department of Pathology, University of Oulu and Oulu University Hospital, Finland (R.S.); and Oulu Center for Cell-Matrix Research, Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Finland (L.E.)
| | - Sinem Karaman
- From the Wihuri Research Institute and Translational Cancer Biology Research Program, Biomedicum Helsinki, University of Helsinki, Finland (K.H., S.K., G.D'A., T.T., K.A., G.Z.); Biocenter Oulu and Department of Pathology, University of Oulu and Oulu University Hospital, Finland (R.S.); and Oulu Center for Cell-Matrix Research, Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Finland (L.E.)
| | - Gabriela D'Amico
- From the Wihuri Research Institute and Translational Cancer Biology Research Program, Biomedicum Helsinki, University of Helsinki, Finland (K.H., S.K., G.D'A., T.T., K.A., G.Z.); Biocenter Oulu and Department of Pathology, University of Oulu and Oulu University Hospital, Finland (R.S.); and Oulu Center for Cell-Matrix Research, Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Finland (L.E.)
| | - Tuomas Tammela
- From the Wihuri Research Institute and Translational Cancer Biology Research Program, Biomedicum Helsinki, University of Helsinki, Finland (K.H., S.K., G.D'A., T.T., K.A., G.Z.); Biocenter Oulu and Department of Pathology, University of Oulu and Oulu University Hospital, Finland (R.S.); and Oulu Center for Cell-Matrix Research, Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Finland (L.E.)
| | - Raija Sormunen
- From the Wihuri Research Institute and Translational Cancer Biology Research Program, Biomedicum Helsinki, University of Helsinki, Finland (K.H., S.K., G.D'A., T.T., K.A., G.Z.); Biocenter Oulu and Department of Pathology, University of Oulu and Oulu University Hospital, Finland (R.S.); and Oulu Center for Cell-Matrix Research, Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Finland (L.E.)
| | - Lauri Eklund
- From the Wihuri Research Institute and Translational Cancer Biology Research Program, Biomedicum Helsinki, University of Helsinki, Finland (K.H., S.K., G.D'A., T.T., K.A., G.Z.); Biocenter Oulu and Department of Pathology, University of Oulu and Oulu University Hospital, Finland (R.S.); and Oulu Center for Cell-Matrix Research, Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Finland (L.E.)
| | - Kari Alitalo
- From the Wihuri Research Institute and Translational Cancer Biology Research Program, Biomedicum Helsinki, University of Helsinki, Finland (K.H., S.K., G.D'A., T.T., K.A., G.Z.); Biocenter Oulu and Department of Pathology, University of Oulu and Oulu University Hospital, Finland (R.S.); and Oulu Center for Cell-Matrix Research, Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Finland (L.E.)
| | - Georgia Zarkada
- From the Wihuri Research Institute and Translational Cancer Biology Research Program, Biomedicum Helsinki, University of Helsinki, Finland (K.H., S.K., G.D'A., T.T., K.A., G.Z.); Biocenter Oulu and Department of Pathology, University of Oulu and Oulu University Hospital, Finland (R.S.); and Oulu Center for Cell-Matrix Research, Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Finland (L.E.).
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19
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FTY720 Attenuates Angiotensin II-Induced Podocyte Damage via Inhibiting Inflammatory Cytokines. Mediators Inflamm 2017; 2017:3701385. [PMID: 28270699 PMCID: PMC5320072 DOI: 10.1155/2017/3701385] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 12/08/2016] [Accepted: 12/26/2016] [Indexed: 12/29/2022] Open
Abstract
FTY720, a new chemical substance derived from the ascomycete Isaria sinclairii, is used for treating multiple sclerosis, renal cancer, and asthma. Sphingosine 1-phosphate (S1P) is a bioactive sphingolipid metabolite and exists in red blood cells. FTY720 is a synthetic S1P analog which can block S1P evoking physiological effects. Recently studies show that S1P was participating in activated inflammation cells induced renal injury. The objective of this study was to assess the protective effect of FTY720 on kidney damage and the potential mechanism of FTY720 which alleviate podocyte injury in chronic kidney disease. In this study, we selected 40 patients with IgA nephropathy and examined their clinical characteristics. Ang II-infusion rat renal injury model was established to evaluate the glomeruli and tubulointerstitial lesion. The result showed that the concentration of S1P in serum and urine was positively correlated with IgA nephropathy patients' renal injury. FTY720 could reduce renal histological lesions induced by Ang II-infusion in rats. Moreover, FTY720 decreased S1P synthesis in Ang II-infusion rats via downregulation of inflammatory cytokines including TNF-α and IL-6. In addition, FTY720 alleviated exogenous S1P-induced podocyte damage. In conclusion, FTY720 is able to attenuate S1P-induced podocyte damage via reducing inflammatory cytokines.
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20
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Cathepsin L is crucial for the development of early experimental diabetic nephropathy. Kidney Int 2016; 90:1012-1022. [DOI: 10.1016/j.kint.2016.06.035] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 06/22/2016] [Accepted: 06/30/2016] [Indexed: 11/20/2022]
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Abstract
Endothelin-1 (ET-1) is a 21-amino acid peptide with mitogenic and powerful vasoconstricting properties. Under healthy conditions, ET-1 is expressed constitutively in all cells of the glomerulus and participates in homeostasis of glomerular structure and filtration function. Under disease conditions, increases in ET-1 are critically involved in initiating and maintaining glomerular inflammation, glomerular basement membrane hypertrophy, and injury of podocytes (visceral epithelial cells), thereby promoting proteinuria and glomerulosclerosis. Here, we review the role of ET-1 in the function of glomerular endothelial cells, visceral (podocytes) and parietal epithelial cells, mesangial cells, the glomerular basement membrane, stromal cells, inflammatory cells, and mesenchymal stem cells. We also discuss molecular mechanisms by which ET-1, predominantly through activation of the ETA receptor, contributes to injury to glomerular cells, and review preclinical and clinical evidence supporting its pathogenic role in glomerular injury in chronic renal disease. Finally, the therapeutic rationale for endothelin antagonists as a new class of antiproteinuric drugs is discussed.
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Affiliation(s)
- Matthias Barton
- Molecular Internal Medicine, University of Zurich, Zurich, Switzerland.
| | - Andrey Sorokin
- Department of Medicine, Kidney Disease Center, Division of Nephrology, Medical College of Wisconsin, Milwaukee, WI
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22
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Rheault MN, Gbadegesin RA. The Genetics of Nephrotic Syndrome. J Pediatr Genet 2015; 5:15-24. [PMID: 27617138 DOI: 10.1055/s-0035-1557109] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 01/21/2015] [Indexed: 12/26/2022]
Abstract
Nephrotic syndrome (NS) is a common pediatric kidney disease and is defined as massive proteinuria, hypoalbuminemia, and edema. Dysfunction of the glomerular filtration barrier, which is made up of endothelial cells, glomerular basement membrane, and visceral epithelial cells known as podocytes, is evident in children with NS. While most children have steroid-responsive nephrotic syndrome (SSNS), approximately 20% have steroid-resistant nephrotic syndrome (SRNS) and are at risk for progressive kidney dysfunction. While the cause of SSNS is still not well understood, there has been an explosion of research into the genetic causes of SRNS in the past 15 years. More than 30 proteins regulating the function of the glomerular filtration barrier have been associated with SRNS including podocyte slit diaphragm proteins, podocyte actin cytoskeletal proteins, mitochondrial proteins, adhesion and glomerular basement membrane proteins, transcription factors, and others. A genetic cause of SRNS can be found in approximately 70% of infants presenting in the first 3 months of life and 50% of infants presenting between 4 and 12 months, with much lower likelihood for older patients. Identification of the underlying genetic etiology of SRNS is important in children because it allows for counseling of other family members who may be at risk, predicts risk of recurrent disease after kidney transplant, and predicts response to immunosuppressive therapy. Correlations between genetic mutation and clinical phenotype as well as genetic risk factors for SSNS and SRNS are reviewed in this article.
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Affiliation(s)
- Michelle N Rheault
- Division of Nephrology, University of Minnesota Masonic Children's Hospital, Minneapolis, Minnesota, United States
| | - Rasheed A Gbadegesin
- Division of Nephrology and Center for Human Genetics, Duke University Medical Center, Durham, North Carolina, United States
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23
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Barutta F, Grimaldi S, Franco I, Bellini S, Gambino R, Pinach S, Corbelli A, Bruno G, Rastaldi MP, Aveta T, Hirsch E, Di Marzo V, Gruden G. Deficiency of cannabinoid receptor of type 2 worsens renal functional and structural abnormalities in streptozotocin-induced diabetic mice. Kidney Int 2014; 86:979-90. [DOI: 10.1038/ki.2014.165] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 03/25/2014] [Accepted: 03/27/2014] [Indexed: 01/09/2023]
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24
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Jin X, Wang W, Mao J, Shen H, Fu H, Wang X, Gu W, Liu A, Yu H, Shu Q, Du L. Overexpression of Myo1e in mouse podocytes enhances cellular endocytosis, migration, and adhesion. J Cell Biochem 2014; 115:410-9. [PMID: 24339252 DOI: 10.1002/jcb.24676] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 09/11/2013] [Indexed: 01/09/2023]
Abstract
Podocytes are a terminally differentiated and highly specialized cell type in the glomerulus that forms a crucial component of the glomerular filtration barrier. Recently, Myo1e was identified in the podocytes of glomeruli. Myo1e podocyte-specific knockout mice exhibit proteinuria, podocyte foot process effacement, glomerular basement membrane disorganization, signs of chronic renal injury, and kidney inflammation. After overexpression of Myo1e in a conditionally immortalized mouse podocyte cell line (MPC5), podocyte migration was evaluated via transwell assay, endocytosis was evaluated using FITC-transferrin, and adhesion was evaluated using a detachment assay after puromycin aminonucleoside treatment. Myo1e overexpression significantly increased the adherence of podocytes. ANOVA analysis indicated significant differences for cell adhesion between the overexpression and control groups (overexpression vs. control, t = 11.3199, P = 0.005; overexpression vs. negative control, t = 12.0570, P = 0.0006). Overexpression of Myo1e inhibited puromycin aminonucleoside-induced podocyte detachment, and the number of cells remaining on the bottom of the culture plate increased. Cell migration was enhanced in Myo1e-overexpressing podocytes in the transwell migration assay. Internalization of FITC-transferrin also increased in Myo1e-overexpressing podocytes relative to control cells. Overexpression of Myo1e can enhance podocyte migration ability, endocytosis, and attachment to the glomerular basement membrane. Restoration of Myo1e expression in podocytes may therefore strengthen their functional integrity against environmental and mechanical injury.
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Affiliation(s)
- Xia Jin
- Department of Nephrology, The Children's Hospital of Zhejiang University School of Medicine, Hangzhou, 310003, China
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25
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Liu XJ, Zhang YM, Wang SX, Liu G. Ultrastructural changes of podocyte foot processes during the remission phase of minimal change disease of human kidney. Nephrology (Carlton) 2014; 19:392-7. [PMID: 24690133 DOI: 10.1111/nep.12256] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2014] [Indexed: 11/28/2022]
Affiliation(s)
- Xiao-Jing Liu
- Renal Division; Peking University First Hospital; Beijing China
- Institute of Nephrology; Peking University; Beijing China
- Key Laboratory of Renal Disease; Ministry of Health of China; Beijing China
- Key Laboratory of CKD Prevention and Treatment; Ministry of Education of China; Beijing China
| | - Yi-Miao Zhang
- Renal Division; Peking University First Hospital; Beijing China
- Institute of Nephrology; Peking University; Beijing China
- Key Laboratory of Renal Disease; Ministry of Health of China; Beijing China
- Key Laboratory of CKD Prevention and Treatment; Ministry of Education of China; Beijing China
| | - Su-Xia Wang
- Department of Electron Microscopy; Peking University First Hospital; Beijing China
| | - Gang Liu
- Renal Division; Peking University First Hospital; Beijing China
- Institute of Nephrology; Peking University; Beijing China
- Key Laboratory of Renal Disease; Ministry of Health of China; Beijing China
- Key Laboratory of CKD Prevention and Treatment; Ministry of Education of China; Beijing China
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26
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He FF, Chen S, Su H, Meng XF, Zhang C. Actin-associated Proteins in the Pathogenesis of Podocyte Injury. Curr Genomics 2014; 14:477-84. [PMID: 24396279 PMCID: PMC3867723 DOI: 10.2174/13892029113146660014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Revised: 09/24/2013] [Accepted: 09/25/2013] [Indexed: 02/07/2023] Open
Abstract
Podocytes have a complex cellular architecture with interdigitating processes maintained by a precise organization of actin filaments. The actin-based foot processes of podocytes and the interposed slit diaphragm form the final barrier to proteinuria. The function of podocytes is largely based on the maintenance of the normal foot process structure with actin cytoskeleton. Cytoskeletal dynamics play important roles during normal podocyte development, in maintenance of the healthy glomerular filtration barrier, and in the pathogenesis of glomerular diseases. In this review, we focused on recent findings on the mechanisms of organization and reorganization of these actin-related molecules in the pathogenesis of podocyte injury and potential therapeutics targeting the regulation of actin cytoskeleton in podocytopathies.
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Affiliation(s)
- Fang-Fang He
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Shan Chen
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Hua Su
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Xian-Fang Meng
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Chun Zhang
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
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27
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Abstract
In the past decade, research has advanced our understanding how endothelin contributes to proteinuria and glomerulosclerosis. Data from pre-clinical and clinical studies now provide evidence that proteinuric diseases such as focal segmental glomerulosclerosis and diabetic nephropathy as well as hypertension nephropathy are sensitive to treatment with endothelin receptor antagonists (ERAs). Like blockade of the renin-angiotensin system, ERA treatment-under certain conditions-may even cause disease regression, effects that could be achieved on top of renin-angiotensin-aldosterone system blockade, suggesting independent therapeutic mechanisms by which ERAs convey nephroprotection. Beneficial effects of ERAs on podocyte function, which is essential to maintain the glomerular filtration barrier, have been identified as one of the key mechanisms by which inhibition of the endothelin ETA receptor ameliorates renal structure and function. In this article, we will review pre-clinical studies demonstrating a causal role for endothelin in proteinuric chronic kidney disease (with a particular focus on functional and structural integrity of podocytes in vitro and in vivo). We will also review the evidence suggesting a therapeutic benefit of ERA treatment on the functional integrity of podocytes in humans.
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Affiliation(s)
- Matthias Barton
- Molecular Internal Medicine, University of Zürich, Zürich, Switzerland
| | - Pierre-Louis Tharaux
- INSERM and Université Paris Descartes, Sorbonne Paris Cité, Paris Cardiovascular Centre, Paris, France
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Garg P, Rabelink T. Glomerular proteinuria: a complex interplay between unique players. Adv Chronic Kidney Dis 2011; 18:233-42. [PMID: 21782129 DOI: 10.1053/j.ackd.2011.06.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 05/31/2011] [Accepted: 06/01/2011] [Indexed: 11/11/2022]
Abstract
Protein leak in the urine is a harbinger of disruption of the glomerular filtration barrier. It also correlates with disease progression and development of ESRD. At present, therapies are aimed at decreasing proteinuria to decrease further damage to the filter and as a marker of remission. Understanding the mechanism of molecular events that lead to protein leak is vital to developing new therapeutic interventions. There has been tremendous progress over the last decade in identifying gene defects which result in hereditary proteinuric defects. This has led to identifying pathways by which these genes regulate the structure and function of the components of the filtration barrier, namely the podocytes, mesangial cells, endothelial cells, and the basement membrane. Using gene knockout mouse models, a role of tubular cells in regulating proteinuria is also emerging. In this review, we have attempted to present some of the prevailing understanding of the underlying mechanisms and physiology of proteinuria.
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Choi SY, Suh KS, Choi DE, Lim BJ. Morphometric analysis of podocyte foot process effacement in IgA nephropathy and its association with proteinuria. Ultrastruct Pathol 2010; 34:195-8. [PMID: 20594038 DOI: 10.3109/01913121003648402] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The effacement of podocyte foot processes is a well-known phenomenon occurring in many glomerulonephritides with proteinuria. The fundamental sign of IgA nephropathy is hematuria, but proteinuria also frequently occurs. The authors measured the extent of foot process effacement in 100 IgA nephropathy cases with proteinuria and correlated it with the amount of proteinuria. The extent of foot process effacement was greater in the nephrotic proteinuria group than in the subnephrotic proteinuria or control groups. The degree of foot process effacement was positively correlated with proteinuria. This study demonstrates that proteinuria in IgA nephropathy is closely related to foot process effacement.
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Affiliation(s)
- Song Yi Choi
- Department of Pathology, Chungnam National University College of Medicine, Daejeon, Korea
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31
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Barutta F, Corbelli A, Mastrocola R, Gambino R, Di Marzo V, Pinach S, Rastaldi MP, Perin PC, Gruden G. Cannabinoid receptor 1 blockade ameliorates albuminuria in experimental diabetic nephropathy. Diabetes 2010; 59:1046-54. [PMID: 20068137 PMCID: PMC2844813 DOI: 10.2337/db09-1336] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE Cannabinoid receptor 1 (CB1) is localized in the central nervous system and in peripheral tissues involved in energy metabolism control. However, CB1 receptors are also expressed at low level within the glomeruli, and the aim of this study was to investigate their potential relevance in the pathogenesis of proteinuria in experimental type 1 diabetes. RESEARCH DESIGN AND METHODS Streptozotocin-induced diabetic mice were treated with N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,3-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251), a selective CB1-receptor antagonist, at the dosage of 1 mg x kg(-1) x day(-1) via intraperitoneal injection for 14 weeks. Urinary albumin excretion was measured by enzyme-linked immunosorbent assay. CB1 receptor expression was studied by immunohistochemistry, immunoblotting, and real-time PCR. Expression of nephrin, podocin, synaptopodin, and zonula occludens-1 (ZO-1) was assessed by immunofluorescence and real-time PCR. Fibronectin, transforming growth factor-beta1 (TGF-beta1), and connective tissue growth factor (CTGF) mRNA levels were quantitated by real-time PCR. RESULTS In diabetic mice, the CB1 receptor was overexpressed within the glomeruli, predominantly by glomerular podocytes. Blockade of the CB1 receptor did not affect body weight, blood glucose, and blood pressure levels in either diabetic or control mice. Albuminuria was increased in diabetic mice compared with control animals and was significantly ameliorated by treatment with AM251. Furthermore, CB1 blockade completely prevented diabetes-induced downregulation of nephrin, podocin, and ZO-1. By contrast overexpression of fibronectin, TGF-beta1, and CTGF in renal cortex of diabetic mice was unaltered by AM251 administration. CONCLUSIONS In experimental type 1 diabetes, the CB1 receptor is overexpressed by glomerular podocytes, and blockade of the CB1 receptor ameliorates albuminuria possibly via prevention of nephrin, podocin, and ZO-1 loss.
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Affiliation(s)
- Federica Barutta
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Turin, Italy
| | - Alessandro Corbelli
- Renal Research Laboratory, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Ospedale Maggiore Policlinico and Fondazione D'Amico per la Ricerca sulle Malattie Renali, Milan, Italy
- MIA Consortium for Image Analysis, Milano Bicocca University, Milan, Italy
| | - Raffaella Mastrocola
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Turin, Italy
| | - Roberto Gambino
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Turin, Italy
| | - Vincenzo Di Marzo
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, Pozzuoli, Italy
| | - Silvia Pinach
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Turin, Italy
| | - Maria Pia Rastaldi
- Renal Research Laboratory, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Ospedale Maggiore Policlinico and Fondazione D'Amico per la Ricerca sulle Malattie Renali, Milan, Italy
| | - Paolo Cavallo Perin
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Turin, Italy
| | - Gabriella Gruden
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Turin, Italy
- Corresponding author: Gabriella Gruden,
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Barton M. Therapeutic potential of endothelin receptor antagonists for chronic proteinuric renal disease in humans. Biochim Biophys Acta Mol Basis Dis 2010; 1802:1203-13. [PMID: 20359530 DOI: 10.1016/j.bbadis.2010.03.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2010] [Revised: 03/23/2010] [Accepted: 03/25/2010] [Indexed: 11/26/2022]
Abstract
Diabetes and arterial hypertension continue to be the main causes of chronic renal failure in 2010, with a rising prevalence in part due to the worldwide obesity epidemic. Proteinuria is a main feature of chronic renal disease and mediated by defects in the glomerular filtration barrier and is as a good predictor of cardiovascular events. Indeed, chronic renal disease due to glomerulosclerosis is one of the important risk factors for the development of coronary artery disease and stroke. Glomerulosclerosis develops in response to inflammatory activation and increased growth factor production. Preclinical and first preliminary clinical studies provide strong evidence that endogenous endothelin-1 (ET-1), a 21-amino-acid peptide with strong growth-promoting and vasoconstricting properties, plays a central role in the pathogenesis of proteinuria and glomerulosclerosis via activation of its ET(A) subtype receptor involving podocyte injury. These studies have not only shown that endothelin participates in the disease processes of hypertension and glomerulosclerosis but also that features of chronic renal disease such as proteinuria and glomerulosclerosis are reversible processes. Remarkably, the protective effects of endothelin receptors antagonists (ERAs) are present even on top of concomitant treatments with inhibitors of the renin-angiotensin system. This review discusses current evidence for a role of endothelin for proteinuric renal disease and podocyte injury in diabetes and arterial hypertension and reviews the current status of endothelin receptor antagonists as a potential new treatment option in renal medicine.
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Affiliation(s)
- Matthias Barton
- Molecular Internal Medicine, University of Zurich, LTK Y 44 G 22, Winterthurer Strasse 190, CH-8057 Zürich, Switzerland.
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Veron D, Reidy KJ, Bertuccio C, Teichman J, Villegas G, Jimenez J, Shen W, Kopp JB, Thomas DB, Tufro A. Overexpression of VEGF-A in podocytes of adult mice causes glomerular disease. Kidney Int 2010; 77:989-99. [PMID: 20375978 DOI: 10.1038/ki.2010.64] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We sought to examine the pathogenic role of excessive VEGF-A expression in podocytes, since it has been reported that diabetic nephropathy and other glomerular diseases are associated with increased VEGF-A expression. The induction of podocyte-specific VEGF164 overexpression in adult transgenic mice led to proteinuria, glomerulomegaly, glomerular basement membrane thickening, mesangial expansion, loss of slit diaphragms, and podocyte effacement. When doxycycline-mediated VEGF164 was stopped, these abnormalities reversed. These findings were associated with reversible downregulation of metalloproteinase 9 and nephrin expression. Using transmission electron microscopy, we established that VEGF-A receptor-2 (VEGFR2) was expressed in podocytes and glomerular endothelial cells. We also found that VEGF164 induced VEGFR2 phosphorylation in podocytes. Further, we were able to co-immunoprecipitate VEGFR2 and nephrin using whole kidney lysates, confirming interaction in vivo. This implies that autocrine and paracrine VEGF-A signaling through VEGFR2 occurs in podocytes and may mediate the glomerular phenotype caused by VEGF164 overexpression. Thus, we suggest that podocyte VEGF164 overexpression in adult mice is sufficient to induce glomerular filtration barrier structural and functional abnormalities similar to those present in murine diabetic nephropathy.
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Affiliation(s)
- Delma Veron
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
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34
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Tarabra E, Giunti S, Barutta F, Salvidio G, Burt D, Deferrari G, Gambino R, Vergola D, Pinach S, Perin PC, Camussi G, Gruden G. Effect of the monocyte chemoattractant protein-1/CC chemokine receptor 2 system on nephrin expression in streptozotocin-treated mice and human cultured podocytes. Diabetes 2009; 58:2109-18. [PMID: 19587356 PMCID: PMC2731530 DOI: 10.2337/db08-0895] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
OBJECTIVE Monocyte chemoattractant protein-1 (MCP-1), a chemokine binding to the CC chemokine receptor 2 (CCR2) and promoting monocyte infiltration, has been implicated in the pathogenesis of diabetic nephropathy. To assess the potential relevance of the MCP-1/CCR2 system in the pathogenesis of diabetic proteinuria, we studied in vitro if MCP-1 binding to the CCR2 receptor modulates nephrin expression in cultured podocytes. Moreover, we investigated in vivo if glomerular CCR2 expression is altered in kidney biopsies from patients with diabetic nephropathy and whether lack of MCP-1 affects proteinuria and expression of nephrin in experimental diabetes. RESEARCH DESIGN AND METHODS Expression of nephrin was assessed in human podocytes exposed to rh-MCP-1 by immunofluorescence and real-time PCR. Glomerular CCR2 expression was studied in 10 kidney sections from patients with overt nephropathy and eight control subjects by immunohistochemistry. Both wild-type and MCP-1 knockout mice were made diabetic with streptozotocin. Ten weeks after the onset of diabetes, albuminuria and expression of nephrin, synaptopodin, and zonula occludens-1 were examined by immunofluorescence and immunoblotting. RESULTS In human podocytes, MCP-1 binding to the CCR2 receptor induced a significant reduction in nephrin both mRNA and protein expression via a Rho-dependent mechanism. The MCP-1 receptor, CCR2, was overexpressed in the glomerular podocytes of patients with overt nephropathy. In experimental diabetes, MCP-1 was overexpressed within the glomeruli and the absence of MCP-1 reduced both albuminuria and downregulation of nephrin and synaptopodin. CONCLUSIONS These findings suggest that the MCP-1/CCR2 system may be relevant in the pathogenesis of proteinuria in diabetes.
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Affiliation(s)
- Elena Tarabra
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Italy
| | - Sara Giunti
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Italy
- Emergency Medicine Division, Umberto Parini Hospital, Aosta, Italy
| | - Federica Barutta
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Italy
| | | | - Davina Burt
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Italy
| | | | - Roberto Gambino
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Italy
| | | | - Silvia Pinach
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Italy
| | - Paolo Cavallo Perin
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Italy
| | - Giovanni Camussi
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Italy
| | - Gabriella Gruden
- Diabetic Nephropathy Laboratory, Department of Internal Medicine, University of Turin, Italy
- Corresponding author: Gabriella Gruden,
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Mollet G, Ratelade J, Boyer O, Muda AO, Morisset L, Lavin TA, Kitzis D, Dallman MJ, Bugeon L, Hubner N, Gubler MC, Antignac C, Esquivel EL. Podocin inactivation in mature kidneys causes focal segmental glomerulosclerosis and nephrotic syndrome. J Am Soc Nephrol 2009; 20:2181-9. [PMID: 19713307 DOI: 10.1681/asn.2009040379] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Podocin is a critical component of the glomerular slit diaphragm, and genetic mutations lead to both familial and sporadic forms of steroid-resistant nephrotic syndrome. In mice, constitutive absence of podocin leads to rapidly progressive renal disease characterized by mesangiolysis and/or mesangial sclerosis and nephrotic syndrome. Using established Cre-loxP technology, we inactivated podocin in the adult mouse kidney in a podocyte-specific manner. Progressive loss of podocin in the glomerulus recapitulated albuminuria, hypercholesterolemia, hypertension, and renal failure seen in nephrotic syndrome in humans. Lesions of FSGS appeared after 4 wk, with subsequent development of diffuse glomerulosclerosis and tubulointerstitial damage. Interestingly, conditional inactivation of podocin at birth resulted in a gradient of glomerular lesions, including mesangial proliferation, demonstrating a developmental stage dependence of renal histologic patterns of injury. The development of significant albuminuria in this model occurred only after early and focal foot process effacement had progressed to diffuse involvement, with complete absence of podocin immunolabeling at the slit diaphragm. Finally, we identified novel potential mediators and perturbed molecular pathways, including cellular proliferation, in the course of progression of renal disease leading to glomerulosclerosis, using global gene expression profiling.
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Julian BA, Suzuki H, Suzuki Y, Tomino Y, Spasovski G, Novak J. Sources of Urinary Proteins and their Analysis by Urinary Proteomics for the Detection of Biomarkers of Disease. Proteomics Clin Appl 2009; 3:1029-1043. [PMID: 20161589 PMCID: PMC2808139 DOI: 10.1002/prca.200800243] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Accepted: 04/20/2009] [Indexed: 11/07/2022]
Abstract
Renal disorders account for a substantial fraction of the budget for health care in many countries. Proteinuria is a frequent manifestation in afflicted patients, but the origin of the proteins varies based on the nature of the disorder. The emerging field of urinary proteomics has the potential to replace kidney biopsy as the diagnostic procedure of choice for patients with some glomerular forms of renal disease. To fully realize this potential, it is vital to understand the basis for the urinary excretion of protein in physiological and pathological conditions. In this review, we discuss the structure of the nephron, the functional unit of the kidney, and the process by which proteins/peptides enter the urine. We discuss several aspects of proteinuria that impact the proteomic analysis of urine of patients with renal diseases.
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Affiliation(s)
| | - Hitoshi Suzuki
- University of Alabama at Birmingham, Birmingham, AL, USA
- Juntendo University School of Medicine, Tokyo, Japan
| | - Yusuke Suzuki
- Juntendo University School of Medicine, Tokyo, Japan
| | | | | | - Jan Novak
- University of Alabama at Birmingham, Birmingham, AL, USA
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Fissell WH, Hofmann CL, Ferrell N, Schnell L, Dubnisheva A, Zydney AL, Yurchenco PD, Roy S. Solute partitioning and filtration by extracellular matrices. Am J Physiol Renal Physiol 2009; 297:F1092-100. [PMID: 19587146 DOI: 10.1152/ajprenal.00162.2009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The physiology of glomerular filtration remains mechanistically obscure despite its importance in disease. The correspondence between proteinuria and foot process effacement suggests podocytes as the locus of the filtration barrier. If so, retained macromolecules ought to accumulate at the filtration barrier, an effect called concentration polarization. Literature data indicate macromolecule concentrations decrease from subendothelial to subepithelial glomerular basement membrane (GBM), as would be expected if the GBM were itself the filter. The objective of this study was to obtain insights into the possible role of the GBM in protein retention by performing fundamental experimental and theoretical studies on the properties of three model gels. Solute partitioning and filtration through thin gels of a commercially available laminin-rich extracellular matrix, Matrigel, were measured using a polydisperse polysaccharide tracer molecule, Ficoll 70. Solute partitioning into laminin gels and lens basement membrane (LBM) were measured using Ficoll 70. A novel model of a laminin gel was numerically simulated, as well as a mixed structure-random-fiber model for LBM. Experimental partitioning was predicted by numerical simulations. Sieving coefficients through thin gels of Matrigel were size dependent and strongly flux dependent. The observed flux dependence arose from compression of the gel in response to the applied pressure. Gel compression may alter solute partitioning into extracellular matrix at physiologic pressures present in the glomerular capillary. This suggests a physical mechanism coupling podocyte structure to permeability characteristics of the GBM.
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Affiliation(s)
- William H Fissell
- Biomedical Engineering/ND20, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195, USA.
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38
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Angiotensin II type 2 receptor deficiency aggravates renal injury and reduces survival in chronic kidney disease in mice. Kidney Int 2009; 75:1039-49. [DOI: 10.1038/ki.2009.2] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Catanuto P, Doublier S, Lupia E, Fornoni A, Berho M, Karl M, Striker GE, Xia X, Elliot S. 17 beta-estradiol and tamoxifen upregulate estrogen receptor beta expression and control podocyte signaling pathways in a model of type 2 diabetes. Kidney Int 2009; 75:1194-1201. [PMID: 19279558 DOI: 10.1038/ki.2009.69] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Diabetic nephropathy remains one of the most important causes of end-stage renal disease. This is particularly true for women from racial/ethnic minorities. Although administration of 17beta-estradiol to diabetic animals has been shown to reduce extracellular matrix deposition in glomeruli and mesangial cells, effects on podocytes are lacking. Given that podocyte injury has been implicated as a factor leading to the progression of proteinuria and diabetic nephropathy, we treated db/db mice, a model of type 2 diabetic glomerulosclerosis, with 17beta-estradiol or tamoxifen to determine whether these treatments reduce podocyte injury and decrease glomerulosclerosis. We found that albumin excretion, glomerular volume, and extracellular matrix accumulation were decreased in these mice compared to placebo treatment. Podocytes isolated from all treatment groups were immortalized and these cell lines were found to express the podocyte markers WT-1, nephrin, and the TRPC6 cation channel. Tamoxifen and 17beta-estradiol treatment decreased podocyte transforming growth factor-beta mRNA expression but increased that of the estrogen receptor subtype beta protein. 17beta-estradiol, but not tamoxifen, treatment decreased extracellular-regulated kinase phosphorylation. These data, combined with improved albumin excretion, reduced glomerular size, and decreased matrix accumulation, suggest that both 17beta-estradiol and tamoxifen may protect podocytes against injury and therefore ameliorate diabetic nephropathy.
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Affiliation(s)
- Paola Catanuto
- Study Group and Laboratory on Sex and Gender Differences in Health and Disease, University of Miami, Miller School of Medicine, Miami, Florida, USA; Department of Surgery, University of Miami, Miller School of Medicine, Miami, Florida, USA
| | - Sophie Doublier
- Study Group and Laboratory on Sex and Gender Differences in Health and Disease, University of Miami, Miller School of Medicine, Miami, Florida, USA; Department of Genetics, Biology and Biochemistry, University of Turin, Turin, Italy
| | - Enrico Lupia
- Study Group and Laboratory on Sex and Gender Differences in Health and Disease, University of Miami, Miller School of Medicine, Miami, Florida, USA; Azienda Ospedaliera San Giovanni Battista, Turin, Italy
| | - Alessia Fornoni
- Division of Nephrology, University of Miami, Miller School of Medicine, Miami, Florida, USA
| | - Mariana Berho
- Study Group and Laboratory on Sex and Gender Differences in Health and Disease, University of Miami, Miller School of Medicine, Miami, Florida, USA
| | - Michael Karl
- Study Group and Laboratory on Sex and Gender Differences in Health and Disease, University of Miami, Miller School of Medicine, Miami, Florida, USA; Division of Endocrinology, Department of Medicine, University of Miami, Miller School of Medicine, Miami, Florida, USA
| | - Gary E Striker
- Department of Surgery, University of Miami, Miller School of Medicine, Miami, Florida, USA
| | - Xiaomei Xia
- Study Group and Laboratory on Sex and Gender Differences in Health and Disease, University of Miami, Miller School of Medicine, Miami, Florida, USA; Department of Surgery, University of Miami, Miller School of Medicine, Miami, Florida, USA
| | - Sharon Elliot
- Study Group and Laboratory on Sex and Gender Differences in Health and Disease, University of Miami, Miller School of Medicine, Miami, Florida, USA; Department of Surgery, University of Miami, Miller School of Medicine, Miami, Florida, USA.
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40
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Barisoni L, Schnaper HW, Kopp JB. Advances in the biology and genetics of the podocytopathies: implications for diagnosis and therapy. Arch Pathol Lab Med 2009; 133:201-16. [PMID: 19195964 DOI: 10.5858/133.2.201] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/25/2008] [Indexed: 11/06/2022]
Abstract
CONTEXT Etiologic factors and pathways leading to altered podocyte phenotype are clearly numerous and involve the activity of different cellular function. OBJECTIVE To focus on recent discoveries in podocyte biology and genetics and their relevance to these human glomerular diseases, named podocytopathies. DATA SOURCES Genetic mutations in genes encoding for proteins in the nucleus, slit diaphragm, podocyte cytoplasm, and cell membrane are responsible for podocyte phenotype and functional abnormalities. Podocyte injury may also derive from secondary stimuli, such as mechanical stress, infections, or use of certain medications. Podocytes can respond to injury in a limited number of ways, which include (1) effacement, (2) apoptosis, (3) arrest of development, and (4) dedifferentiation. Each of these pathways results in a specific glomerular morphology: minimal change nephropathy, focal segmental glomerulosclerosis, diffuse mesangial sclerosis, and collapsing glomerulopathy. CONCLUSIONS Based on current knowledge of podocyte biology, we organized etiologic factors and morphologic features in a taxonomy of podocytopathies, which provides a novel approach to the classification of these diseases. Current and experimental therapeutic approaches are also discussed.
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Affiliation(s)
- Laura Barisoni
- Department of Pathology and Medicine, Division of Nephrology, New York University School of Medicine, New York, NY 10017, USA.
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41
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Barisoni L, Schnaper HW, Kopp JB. Advances in the biology and genetics of the podocytopathies: implications for diagnosis and therapy. Arch Pathol Lab Med 2009. [PMID: 19195964 DOI: 10.1043/1543-2165-133.2.201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
CONTEXT Etiologic factors and pathways leading to altered podocyte phenotype are clearly numerous and involve the activity of different cellular function. OBJECTIVE To focus on recent discoveries in podocyte biology and genetics and their relevance to these human glomerular diseases, named podocytopathies. DATA SOURCES Genetic mutations in genes encoding for proteins in the nucleus, slit diaphragm, podocyte cytoplasm, and cell membrane are responsible for podocyte phenotype and functional abnormalities. Podocyte injury may also derive from secondary stimuli, such as mechanical stress, infections, or use of certain medications. Podocytes can respond to injury in a limited number of ways, which include (1) effacement, (2) apoptosis, (3) arrest of development, and (4) dedifferentiation. Each of these pathways results in a specific glomerular morphology: minimal change nephropathy, focal segmental glomerulosclerosis, diffuse mesangial sclerosis, and collapsing glomerulopathy. CONCLUSIONS Based on current knowledge of podocyte biology, we organized etiologic factors and morphologic features in a taxonomy of podocytopathies, which provides a novel approach to the classification of these diseases. Current and experimental therapeutic approaches are also discussed.
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Affiliation(s)
- Laura Barisoni
- Department of Pathology and Medicine, Division of Nephrology, New York University School of Medicine, New York, NY 10017, USA.
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42
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Pawar RD, Castrezana-Lopez L, Allam R, Kulkarni OP, Segerer S, Radomska E, Meyer TN, Schwesinger CM, Akis N, Gröne HJ, Anders HJ. Bacterial lipopeptide triggers massive albuminuria in murine lupus nephritis by activating Toll-like receptor 2 at the glomerular filtration barrier. Immunology 2008; 128:e206-21. [PMID: 19175801 DOI: 10.1111/j.1365-2567.2008.02948.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
What are the molecular mechanisms of bacterial infections triggering or modulating lupus nephritis? In nephritic MRL(lpr/lpr) mice, transient exposure to bacterial cell wall components such as lipopeptide or lipopolysaccharide (LPS) increased splenomegaly, the production of DNA autoantibodies, and serum interleukin (IL)-6, IL-12 and tumour necrosis factor (TNF) levels, and aggravated lupus nephritis. Remarkably, bacterial lipopeptide induced massive albuminuria in nephritic but not in non-nephritic mice. This was associated with down-regulation of renal nephrin mRNA and redistribution from its normal localization at foot processes to the perinuclear podocyte area in nephritic MRL(lpr/lpr) mice. Bacterial lipopeptide activates Toll-like receptor 2 (TLR2), which we found to be expressed on cultured podocytes and glomerular endothelial cells. TNF and interferon (IFN)-gamma induced TLR2 mRNA and receptor expression in both cell types. Albumin permeability was significantly increased in cultured podocytes and glomerular endothelial cells upon stimulation by bacterial lipopeptide. LPS also induced moderate albuminuria. In summary, bacterial lipopeptide and LPS can aggravate glomerulonephritis but only lipopeptide potently induces severe albuminuria in MRL(lpr/lpr) mice.
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Affiliation(s)
- Rahul D Pawar
- Medical Policlinic, University of Munich, Munich, Germany
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43
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Tesař V, Zima T. Recent Progress in the Pathogenesis of Nephrotic Proteinuria. Crit Rev Clin Lab Sci 2008; 45:139-220. [DOI: 10.1080/10408360801934865] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Barton M. Reversal of proteinuric renal disease and the emerging role of endothelin. ACTA ACUST UNITED AC 2008; 4:490-501. [PMID: 18648345 DOI: 10.1038/ncpneph0891] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2008] [Accepted: 06/05/2008] [Indexed: 01/18/2023]
Abstract
Proteinuria is a major long-term clinical consequence of diabetes and hypertension, conditions that lead to progressive loss of functional renal tissue and, ultimately, end-stage renal disease. Proteinuria is also a strong predictor of cardiovascular events. Convincing preclinical and clinical evidence exists that proteinuria and the underlying glomerulosclerosis are reversible processes. This Review outlines the mechanisms involved in the development of glomerulosclerosis--particularly those responsible for podocyte injury--with an emphasis on the potential capacity of endothelin receptor blockade to reverse this process. There is strong evidence that endothelin-1, a peptide with growth-promoting and vasoconstricting properties, has a central role in the pathogenesis of proteinuria and glomerulosclerosis, which is mediated via activation of the ET(A) receptor. Several antiproteinuric drugs, including angiotensin-converting-enzyme inhibitors, angiotensin receptor antagonists, statins and certain calcium channel blockers, inhibit the formation of endothelin-1. Preclinical studies have demonstrated that endothelin receptor antagonists can reverse proteinuric renal disease and glomerulosclerosis, and preliminary studies in humans with renal disease have shown that these drugs have remarkable antiproteinuric effects that are additive to those of standard antiproteinuric therapy. Additional clinical studies are needed.
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Affiliation(s)
- Matthias Barton
- Department of Internal Medicine, Klinik und Poliklinik für Innere Medizin, Universitätsspital Zürich, Zürich, Switzerland.
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Haraldsson B, Nyström J, Deen WM. Properties of the Glomerular Barrier and Mechanisms of Proteinuria. Physiol Rev 2008; 88:451-87. [DOI: 10.1152/physrev.00055.2006] [Citation(s) in RCA: 611] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
This review focuses on the intricate properties of the glomerular barrier. Other reviews have focused on podocyte biology, mesangial cells, and the glomerular basement membrane (GBM). However, since all components of the glomerular membrane are important for its function, proteinuria will occur regardless of which layer is affected by disease. We review the properties of endothelial cells and their surface layer, the GBM, and podocytes, discuss various methods of studying glomerular permeability, and analyze data concerning the restriction of solutes by size, charge, and shape. We also review the physical principles of transport across biological or artificial membranes and various theoretical models used to predict the fluxes of solutes and water. The glomerular barrier is highly size and charge selective, in qualitative agreement with the classical studies performed 30 years ago. The small amounts of albumin filtered will be reabsorbed by the megalin-cubulin complex and degraded by the proximal tubular cells. At present, there is no unequivocal evidence for reuptake of intact albumin from urine. The cellular components are the key players in restricting solute transport, while the GBM is responsible for most of the resistance to water flow across the glomerular barrier.
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Dunér F, Patrakka J, Xiao Z, Larsson J, Vlamis-Gardikas A, Pettersson E, Tryggvason K, Hultenby K, Wernerson A. Dendrin expression in glomerulogenesis and in human minimal change nephrotic syndrome. Nephrol Dial Transplant 2008; 23:2504-11. [PMID: 18356187 DOI: 10.1093/ndt/gfn100] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Dendrin is an 81-kD cytosolic protein hitherto described in the brain, where it is associated with the actin cytoskeleton. Recently, we found dendrin in foot processes of mouse glomerular podocytes. Here we describe its expression both during mouse glomerulogenesis and in the normal and diseased human kidney for the first time. METHODS Dendrin expression was characterized using RT-PCR and immunohistochemistry and semi-quantified using immunoelectron microscopy. RESULTS In glomerulogenesis, dendrin mRNA and protein appeared first at the early capillary loop stage. It was concentrated to the pre-podocytes on the basal side of podocalyxin, an apical cell membrane marker. In human tissue, dendrin transcripts were detected in the brain and kidney. In the mature kidney dendrin localized solely in the podocytes, close to the filtration slit diaphragms. A comparison with the slit-associated protein zonula occludens-1 (ZO-1) was done in minimal change nephrotic syndrome (MCNS). Dendrin and ZO-1 were re-distributed from slit regions to the podocyte cytoplasm in areas with foot process effacement (FPE). In areas without FPE, dendrin and ZO-1 distributions were unchanged compared to controls. The total amounts of dendrin or ZO-1 markers were unchanged. This differs from nephrin that, according to our previous results, is also decreased in non-effaced areas. CONCLUSIONS The expression of dendrin during glomerulogenesis and in the normal human kidney is similar to that previously shown for nephrin, which suggests that dendrin associates with the slit diaphragm complex. In MCNS patients, dendrin and ZO-1 are re-distributed within the podocytes. Whether this is a cause or a consequence of FPE remains unclear.
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Affiliation(s)
- Fredrik Dunér
- Department of Clinical Science, Karolinska Institutet, Stockholm, Sweden.
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ASANUMA KATSUHIKO, YANAGIDA-ASANUMA ETSUKO, TAKAGI MIYUKI, KODAMA FUMIKO, TOMINO YASUHIKO. The role of podocytes in proteinuria. Nephrology (Carlton) 2007; 12 Suppl 3:S15-20. [DOI: 10.1111/j.1440-1797.2007.00876.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Kirchhoff F, Krebs C, Abdulhag UN, Meyer-Schwesinger C, Maas R, Helmchen U, Hilgers KF, Wolf G, Stahl RAK, Wenzel U. Rapid development of severe end-organ damage in C57BL/6 mice by combining DOCA salt and angiotensin II. Kidney Int 2007; 73:643-50. [PMID: 18033241 DOI: 10.1038/sj.ki.5002689] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The C57BL/6 mouse strain serves as the genetic background of many transgenic and gene knockout models; however, this strain appears to be resistant to hypertension-induced renal injury. We developed a new model of hypertensive end-organ damage in C57BL/6 mice by combining deoxycorticosterone acetate (DOCA) and salt with angiotensin II infusion. The systolic blood pressure (SBP) was significantly elevated in DOCA salt-angiotensin II mice compared to control mice or mice treated individually with DOCA salt or angiotensin II. Hypertensive glomerular damage, increased expression of profibrotic and inflammatory genes, albuminuria, tubular casts, increased plasma cholesterol, cardiac hypertrophy, and fibrosis were found in mice treated with DOCA salt-angiotensin II. The SBP in the angiotensin II-infused group was further increased by increasing the infusion rate; only mild injury was observed in these mice, suggesting that blood pressure was not a causal factor. Removal of DOCA and the angiotensin pump lowered blood pressure to normal; however, albuminuria along with the glomerular and cardiac damage did not completely resolve. Our study describes a new model of hypertensive end-organ damage and repair in C57BL/6 mice.
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Affiliation(s)
- F Kirchhoff
- Division of Nephrology, Department of Medicine, University Hospital Hamburg-Eppendorf, Hamburg, Germany
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D'Agati VD. Podocyte injury in focal segmental glomerulosclerosis: Lessons from animal models (a play in five acts). Kidney Int 2007; 73:399-406. [PMID: 17989648 DOI: 10.1038/sj.ki.5002655] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Genetic engineering in the mouse has ushered in a new era of disease modeling that has advanced our understanding of podocyte injury in the pathogenesis of focal segmental glomerulosclerosis. Historically, the major animal models of focal segmental glomerulosclerosis involve direct podocyte injury (exemplified by toxin models) and indirect podocyte injury due to adaptive responses (exemplified by renal ablation models). In both paradigms, recent evidence indicates that podocyte depletion is a major pathomechanism mediating proteinuria and glomerulosclerosis. Podocyte-specific toxin models support that podocyte loss is sufficient to cause focal segmental glomerulosclerosis in a dose-dependent manner. Knockout and transgenic models have provided proof of concept that mutations in specific podocyte proteins mediate genetic forms of focal segmental glomerulosclerosis. Transgenic models of HIV-associated nephropathy have helped to elucidate the role of direct viral infection and podocyte expression of viral gene products in the pathogenesis of this form of collapsing glomerulopathy. Taken together, emerging data support that injury directed to or inherent within the podocyte constitutes the critical event in diverse pathways to glomerulosclerosis.
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Affiliation(s)
- V D D'Agati
- Department of Pathology, Columbia University, College of Physicians & Surgeons, New York, New York 10032, USA.
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Abstract
Despite significant advances in our understanding of the molecular structure and composition of the glomerular filtration barrier, the mechanisms underlying the presence of excess protein in the urine (proteinuria) in acquired human kidney diseases remain elusive. In a study appearing in this issue of the JCI, Sever and associates use a combination of biochemical, genetic, and in vivo approaches in mice to demonstrate a pivotal role of cathepsin L and its substrate the GTPase dynamin, in the induction of proteinuria and associated foot process effacement in glomerular podocytes (see the related article beginning on page 2095).
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Affiliation(s)
- Pierre Ronco
- INSERM UMR S 702, University Pierre et Marie Curie, and Department of Nephrology and Dialysis, Tenon Hospital, Paris, France.
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