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Maes A, Borgel O, Braconnier C, Balcaen T, Wevers M, Halbgebauer R, Huber-Lang M, Kerckhofs G. X-Ray-Based 3D Histopathology of the Kidney Using Cryogenic Contrast-Enhanced MicroCT. Int J Biomed Imaging 2024; 2024:3924036. [PMID: 38634014 PMCID: PMC11022514 DOI: 10.1155/2024/3924036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 02/08/2024] [Accepted: 02/27/2024] [Indexed: 04/19/2024] Open
Abstract
The kidney's microstructure, which comprises a highly convoluted tubular and vascular network, can only be partially revealed using classical 2D histology. Considering that the kidney's microstructure is closely related to its function and is often affected by pathologies, there is a need for powerful and high-resolution 3D imaging techniques to visualize the microstructure. Here, we present how cryogenic contrast-enhanced microCT (cryo-CECT) allowed 3D visualization of glomeruli, tubuli, and vasculature. By comparing different contrast-enhancing staining agents and freezing protocols, we found that the preferred sample preparation protocol was the combination of staining with 1:2 hafnium(IV)-substituted Wells-Dawson polyoxometalate and freezing by submersion in isopentane at -78°C. This optimized protocol showed to be highly sensitive, allowing to detect small pathology-induced microstructural changes in a mouse model of mild trauma-related acute kidney injury after thorax trauma and hemorrhagic shock. In summary, we demonstrated that cryo-CECT is an effective 3D histopathological tool that allows to enhance our understanding of kidney tissue microstructure and their related function.
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Affiliation(s)
- Arne Maes
- Department of Materials Engineering, KU Leuven, Heverlee, Belgium
- Biomechanics Lab, Institute of Mechanics, Materials and Civil Engineering, UCLouvain, Louvain-la-Neuve, Belgium
- Pole of Morphology, Institute of Experimental and Clinical Research, UCLouvain, Brussels, Belgium
| | - Onno Borgel
- Institute of Clinical and Experimental Trauma-Immunology, University Hospital Ulm, Ulm, Germany
| | - Clara Braconnier
- Biomechanics Lab, Institute of Mechanics, Materials and Civil Engineering, UCLouvain, Louvain-la-Neuve, Belgium
| | - Tim Balcaen
- Biomechanics Lab, Institute of Mechanics, Materials and Civil Engineering, UCLouvain, Louvain-la-Neuve, Belgium
- Pole of Morphology, Institute of Experimental and Clinical Research, UCLouvain, Brussels, Belgium
- MolDesignS, Sustainable Chemistry for Metals and Molecules, Department of Chemistry, KU Leuven, Leuven, Belgium
| | - Martine Wevers
- Department of Materials Engineering, KU Leuven, Heverlee, Belgium
| | - Rebecca Halbgebauer
- Institute of Clinical and Experimental Trauma-Immunology, University Hospital Ulm, Ulm, Germany
| | - Markus Huber-Lang
- Institute of Clinical and Experimental Trauma-Immunology, University Hospital Ulm, Ulm, Germany
| | - Greet Kerckhofs
- Department of Materials Engineering, KU Leuven, Heverlee, Belgium
- Biomechanics Lab, Institute of Mechanics, Materials and Civil Engineering, UCLouvain, Louvain-la-Neuve, Belgium
- Pole of Morphology, Institute of Experimental and Clinical Research, UCLouvain, Brussels, Belgium
- Prometheus, Division for Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
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2
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Şehirli AÖ, Aksoy U, Sibai A, Orhan K, Sayıner S. Effects of N-acetyl-L-cysteine against apical periodontitis in rats with adriamycin-induced cardiomyopathy and nephropathy. Int Endod J 2024; 57:195-207. [PMID: 38071432 DOI: 10.1111/iej.14010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 10/22/2023] [Accepted: 11/28/2023] [Indexed: 01/11/2024]
Abstract
AIM This study aimed to investigate the potential protective effects of N-acetyl-L-cysteine (NAC) against apical periodontitis (AP) in rats with adriamycin (ADR)-induced kidney and heart diseases. METHODOLOGY Fourty-eight Wistar albino rats were divided into six groups: (1) Control group, (2) ADR group (1 mg/kg/day ip for 10 days), (3) AP Group (1st mandibular molar tooth), (4) AP + ADR Group, (5) AP + NAC group (150 mg/kg/day ip), and (6) AP + ADR + NAC group. After 3 weeks, the rats were decapitated and blood and tissue samples (heart, kidney, and jaw) were collected. Tissue samples were evaluated by biochemical (inflammatory cytokines and hemodynamic parameters) and radiological analyses. One-way anova with Tukey post hoc tests was used to compare data, considering p < .05 as statistically significant. RESULTS The serum levels of TNF-α, IL-1β, BUN, Creatinine, CK, and LDH were elevated in the test groups compared with the control group, and treatment with NAC reduced these levels (p < .05). Heart and kidney tissue analysis showed a higher heart-to-body weight ratio (HW/BW) and kidney-to-body weight ratio (KW/BW) in the test groups compared with the control group (p < .05). No significant differences in HW/BW and KW/BW were found between the control and AP + NAC groups. Volumetric apical bone resorption analysis showed an increase in periapical radiolucencies in AP-induced groups indicating apical periodontitis. NAC treatment reduced the total area and volume of resorption cavities (p < .05). CONCLUSIONS The results suggest that NAC's antioxidant and anti-inflammatory effects can reduce adriamycin-mediated heart and kidney damage and may have a positive effect on apical periodontitis in individuals with nephropathy and cardiomyopathy.
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Affiliation(s)
- Ahmet Özer Şehirli
- Department of Pharmacology, Faculty of Dentistry, Near East University, North Cyprus, Turkey
| | - Umut Aksoy
- Department of Endodontics, Faculty of Dentistry, Near East University, North Cyprus, Turkey
| | - Abdullah Sibai
- Department of Endodontics, Faculty of Dentistry, Near East University, North Cyprus, Turkey
| | - Kaan Orhan
- Department of DentoMaxillofacial Radiology, Faculty of Dentistry, Ankara University, Ankara, Turkey
| | - Serkan Sayıner
- Department of Biochemistry, Faculty of Veterinary Medicine, Near East University, North Cyprus, Turkey
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3
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Denis L, Bodard S, Hingot V, Chavignon A, Battaglia J, Renault G, Lager F, Aissani A, Hélénon O, Correas JM, Couture O. Sensing ultrasound localization microscopy for the visualization of glomeruli in living rats and humans. EBioMedicine 2023; 91:104578. [PMID: 37086650 PMCID: PMC10149190 DOI: 10.1016/j.ebiom.2023.104578] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 04/03/2023] [Accepted: 04/03/2023] [Indexed: 04/24/2023] Open
Abstract
BACKGROUND Estimation of glomerular function is necessary to diagnose kidney diseases. However, the study of glomeruli in the clinic is currently done indirectly through urine and blood tests. A recent imaging technique called Ultrasound Localization Microscopy (ULM) has appeared. It is based on the ability to record continuous movements of individual microbubbles in the bloodstream. Although ULM improved the resolution of vascular imaging up to tenfold, the imaging of the smallest vessels had yet to be reported. METHODS We acquired ultrasound sequences from living humans and rats and then applied filters to divide the data set into slow-moving and fast-moving microbubbles. We performed a double tracking to highlight and characterize populations of microbubbles with singular behaviors. We decided to call this technique "sensing ULM" (sULM). We used post-mortem micro-CT for side-by-side confirmation in rats. FINDINGS In this study, we report the observation of microbubbles flowing in the glomeruli in living humans and rats. We present a set of analysis tools to extract quantitative information from individual microbubbles, such as remanence time or normalized distance. INTERPRETATION As glomeruli play a key role in kidney function, it would be possible that their observation yields a deeper understanding of the kidney. It could also be a tool to diagnose kidney diseases in patients. More generally, it will bring imaging capabilities closer to the functional units of organs, which is a key to understand most diseases, such as cancer, diabetes, or kidney failures. FUNDING This study was funded by the European Research Council under the European Union Horizon H2020 program (ERC Consolidator grant agreement No 772786-ResolveStroke).
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Affiliation(s)
- Louise Denis
- Sorbonne Université, CNRS, INSERM Laboratoire d'Imagerie Biomédicale, F-75006, Paris, France.
| | - Sylvain Bodard
- Sorbonne Université, CNRS, INSERM Laboratoire d'Imagerie Biomédicale, F-75006, Paris, France; AP-HP, Hôpital Necker Enfants Malades, Service d'Imagerie Adulte, F-75015, Paris, France; Université de Paris Cité, F-75006, Paris, France
| | - Vincent Hingot
- Sorbonne Université, CNRS, INSERM Laboratoire d'Imagerie Biomédicale, F-75006, Paris, France
| | - Arthur Chavignon
- Sorbonne Université, CNRS, INSERM Laboratoire d'Imagerie Biomédicale, F-75006, Paris, France
| | - Jacques Battaglia
- Sorbonne Université, CNRS, INSERM Laboratoire d'Imagerie Biomédicale, F-75006, Paris, France
| | - Gilles Renault
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014, Paris, France
| | - Franck Lager
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014, Paris, France
| | - Abderrahmane Aissani
- Sorbonne Université, CNRS, INSERM Laboratoire d'Imagerie Biomédicale, F-75006, Paris, France
| | - Olivier Hélénon
- AP-HP, Hôpital Necker Enfants Malades, Service d'Imagerie Adulte, F-75015, Paris, France; Université de Paris Cité, F-75006, Paris, France
| | - Jean-Michel Correas
- Sorbonne Université, CNRS, INSERM Laboratoire d'Imagerie Biomédicale, F-75006, Paris, France; AP-HP, Hôpital Necker Enfants Malades, Service d'Imagerie Adulte, F-75015, Paris, France; Université de Paris Cité, F-75006, Paris, France
| | - Olivier Couture
- Sorbonne Université, CNRS, INSERM Laboratoire d'Imagerie Biomédicale, F-75006, Paris, France
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4
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Santos R, Bürgi M, Mateos JM, Luciani A, Loffing J. Too bright for 2 dimensions: recent progress in advanced 3-dimensional microscopy of the kidney. Kidney Int 2022; 102:1238-1246. [PMID: 35963448 DOI: 10.1016/j.kint.2022.06.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 06/19/2022] [Accepted: 06/24/2022] [Indexed: 01/12/2023]
Abstract
The kidney is a structurally and functionally complex organ responsible for the control of water, ion, and other solute homeostasis. Moreover, the kidneys excrete metabolic waste products and produce hormones, such as renin and erythropoietin. The functional unit of the kidney is the nephron, which is composed by a serial arrangement of a filter unit called the renal corpuscle and several tubular segments that modulate the filtered fluid by reabsorption and secretion. Within each kidney, thousands of nephrons are closely intermingled and surrounded by an intricate network of blood vessels and various interstitial cell types, including fibroblasts and immune cells. This complex tissue architecture is essential for proper kidney function. In fact, kidney disease is often reflected or even caused by a derangement of the histologic structures. Frequently, kidney histology is studied using microscopic analysis of 2-dimensional tissue sections, which, however, misses important 3-dimensional spatial information. Reconstruction of serial sections tries to overcome this limitation, but is technically challenging, time-consuming, and often inherently linked to sectioning artifacts. In recent years, advances in tissue preparation (e.g., optical clearing) and new light- and electron-microscopic methods have provided novel avenues for 3-dimensional kidney imaging. Combined with novel machine-learning algorithms, these approaches offer unprecedented options for large-scale and automated analysis of kidney structure and function. This review provides a brief overview of these emerging imaging technologies and presents key examples of how these approaches are already used to study the normal and the diseased kidney.
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Affiliation(s)
- Rui Santos
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - Max Bürgi
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - José María Mateos
- Centre for Microscopy and Image Analysis, University of Zurich, Zurich, Switzerland
| | - Alessandro Luciani
- Institute of Physiology, University of Zurich, Zurich, Switzerland; National Centre of Competence in Research "Kidney.CH," University of Zurich, Zurich, Switzerland
| | - Johannes Loffing
- Institute of Anatomy, University of Zurich, Zurich, Switzerland; National Centre of Competence in Research "Kidney.CH," University of Zurich, Zurich, Switzerland.
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5
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Kirk N, Echols MS, Reavill D, Gasper D, Wilcox C. Diagnosis of Seminoma With Metastasis to the Brain and Kidneys in a Moluccan Eclectus (Eclectus roratus) Using Advanced Contrast Based Imaging. J Avian Med Surg 2022; 36:325-332. [DOI: 10.1647/21-00024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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6
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STAT-3 signaling role in an experimental model of nephropathy induced by doxorubicin. Mol Cell Biochem 2022; 478:981-989. [PMID: 36201104 DOI: 10.1007/s11010-022-04574-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 09/23/2022] [Indexed: 01/10/2023]
Abstract
The focal segmental glomerulosclerosis (FSGS) is one of the most frequent glomerulopathy in the world, being considered a significative public health problem worldwide. The disease is characterized by glomerular loss mainly due to inflammation process and collagen fibers deposition. STAT-3 is a transcription factor associated with cell differentiation, migration and proliferation and in renal cells it has been related with fibrosis, acting on the progression of the lesion. Considering this perspective, the present study evaluated the involvement of STAT-3 molecule in an experimental model of FSGS induced by Doxorubicin (DOX). DOX mimics primary FSGS by causing both glomerular and tubular lesions and the inhibition of the STAT3 pathway leads to a decrease in fibrosis and attenuation of kidney damage. We described here a novel FSGS experimental model in a strain of genetically heterogeneous mice which resembles the reality of FSGS patients. DOX-injected mice presented elevated indices of albuminuria and glycosuria, that were significantly reduced in animals treated with a STAT-3 inhibitor (STATTIC), in addition with a decrease of some inflammatory molecules. Moreover, we detected that SOCS-3 (a regulator of STAT family) was up-regulated only in STATTIC-treated mice. Finally, histopathological analyzes showed that DOX-treated group had a significant increase in a tubulointerstitial fibrosis and tubular necrosis, which were not identified in both control and STATTIC groups. Thus, our results indicate that STAT-3 pathway possess an important role in experimental FSGS induced by DOX and may be an important molecule to be further investigated.
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7
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Copur S, Tanriover C, Yavuz F, Soler MJ, Ortiz A, Covic A, Kanbay M. Novel strategies in nephrology: what to expect from the future? Clin Kidney J 2022; 16:230-244. [PMID: 36755838 PMCID: PMC9900595 DOI: 10.1093/ckj/sfac212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Indexed: 11/14/2022] Open
Abstract
Chronic kidney disease (CKD) will become the fifth global case of death by 2040. Its largest impact is on premature mortality but the number of persons with kidney failure requiring renal replacement therapy (RRT) is also increasing dramatically. Current RRT is suboptimal due to the shortage of kidney donors and dismal outcomes associated with both hemodialysis and peritoneal dialysis. Kidney care needs a revolution. In this review, we provide an update on emerging knowledge and technologies that will allow an earlier diagnosis of CKD, addressing the current so-called blind spot (e.g. imaging and biomarkers), and improve renal replacement therapies (wearable artificial kidneys, xenotransplantation, stem cell-derived therapies, bioengineered and bio-artificial kidneys).
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Affiliation(s)
- Sidar Copur
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Cem Tanriover
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Furkan Yavuz
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Maria J Soler
- Department of Nephrology, Vall d’Hebron University Hospital, Universitat Autònoma de Barcelona, Spain,Nephrology and Kidney Transplant Research Group, Vall d'Hebron Research Institute (VHIR), Barcelona, Spain
| | - Alberto Ortiz
- Department of Medicine, Universidad Autonoma de Madrid and IIS-Fundacion Jimenez Diaz, Madrid, Spain
| | - Adrian Covic
- Nephrology Clinic, Dialysis and Renal Transplant Center, ‘C.I. PARHON’ University Hospital, and ‘Grigore T. Popa’ University of Medicine, Iasi, Romania
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8
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Kunishima N, Takeda Y, Hirose R, Kume S, Maeda M, Oguchi A, Yanagita M, Shibuya H, Tamura M, Kataoka Y, Murakawa Y, Ito K, Omote K. Compact laboratory-based X-ray microscope enabling nondestructive 3D structure acquisition of mouse nephron with high speed and better user accessibility. Microscopy (Oxf) 2022; 71:315-323. [PMID: 35778966 PMCID: PMC9731380 DOI: 10.1093/jmicro/dfac033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 06/20/2022] [Accepted: 07/01/2022] [Indexed: 12/15/2022] Open
Abstract
X-ray microscopes adopting computed tomography enable nondestructive 3D visualization of biological specimens at micron-level resolution without conventional 2D serial sectioning that is a destructive/laborious method and is routinely used for analyzing renal biopsy in clinical diagnosis of kidney diseases. Here we applied a compact commercial system of laboratory-based X-ray microscope to observe a resin-embedded osmium-stained 1-mm strip of a mouse kidney piece as a model of renal biopsy, toward a more efficient diagnosis of kidney diseases. A reconstructed computed tomography image from several hours of data collection using CCD detector allowed us to unambiguously segment a single nephron connected to a renal corpuscle, which was consistent with previous reports using serial sectioning. Histogram analysis on the segmented nephron confirmed that the proximal and distal tubules were distinguishable on the basis of their X-ray opacities. A 3D rendering model of the segmented nephron visualized a convoluted structure of renal tubules neighboring the renal corpuscle and a branched structure of efferent arterioles. Furthermore, another data collection using scientific complementary metal-oxide semiconductor detector with a much shorter data acquisition time of 15 min provided similar results from the same samples. These results suggest a potential application of the compact laboratory-based X-ray microscope to analyze mouse renal biopsy.
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Affiliation(s)
| | - Yoshihiro Takeda
- X-ray Research Laboratory, Rigaku Corporation, Akishima, Tokyo 196-8666, Japan
| | - Raita Hirose
- X-ray Research Laboratory, Rigaku Corporation, Akishima, Tokyo 196-8666, Japan
| | - Satoshi Kume
- Laboratory for Pathophysiological and Health Science, RIKEN Center for Biosystems Dynamics Research, Kobe, Hyogo 650-0047, Japan,Center for Health Science Innovation, Osaka City University, Osaka 530-0011, Japan
| | - Mitsuyo Maeda
- Multi-Modal Microstructure Analysis Unit, RIKEN-JEOL Collaboration Center, Kobe, Hyogo 650-0047, Japan
| | - Akiko Oguchi
- RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa 230-0045, Japan,Department of Nephrology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Motoko Yanagita
- Department of Nephrology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan,Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto 606-8501, Japan
| | - Hirotoshi Shibuya
- Technology and Development Team for Mouse Phenotype Analysis, RIKEN BioResource Research Center, Tsukuba, Ibaraki 305-0074, Japan
| | - Masaru Tamura
- Technology and Development Team for Mouse Phenotype Analysis, RIKEN BioResource Research Center, Tsukuba, Ibaraki 305-0074, Japan
| | - Yosky Kataoka
- Multi-Modal Microstructure Analysis Unit, RIKEN-JEOL Collaboration Center, Kobe, Hyogo 650-0047, Japan,Laboratory for Cellular Function Imaging, RIKEN Center for Biosystems Dynamics Research, Kobe, Hyogo 650-0047, Japan
| | - Yasuhiro Murakawa
- RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa 230-0045, Japan,Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto 606-8501, Japan,IFOM―the FIRC Institute of Molecular Oncology, Milan 20139, Italy
| | - Koichiro Ito
- New Market Development Office, Rigaku Corporation, Akishima, Tokyo 196-8666, Japan
| | - Kazuhiko Omote
- X-ray Research Laboratory, Rigaku Corporation, Akishima, Tokyo 196-8666, Japan
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9
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Valverde MG, Mille LS, Figler KP, Cervantes E, Li VY, Bonventre JV, Masereeuw R, Zhang YS. Biomimetic models of the glomerulus. Nat Rev Nephrol 2022; 18:241-257. [PMID: 35064233 PMCID: PMC9949601 DOI: 10.1038/s41581-021-00528-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/08/2021] [Indexed: 12/17/2022]
Abstract
The use of biomimetic models of the glomerulus has the potential to improve our understanding of the pathogenesis of kidney diseases and to enable progress in therapeutics. Current in vitro models comprise organ-on-a-chip, scaffold-based and organoid approaches. Glomerulus-on-a-chip designs mimic components of glomerular microfluidic flow but lack the inherent complexity of the glomerular filtration barrier. Scaffold-based 3D culture systems and organoids provide greater microenvironmental complexity but do not replicate fluid flows and dynamic responses to fluidic stimuli. As the available models do not accurately model the structure or filtration function of the glomerulus, their applications are limited. An optimal approach to glomerular modelling is yet to be developed, but the field will probably benefit from advances in biofabrication techniques. In particular, 3D bioprinting technologies could enable the fabrication of constructs that recapitulate the complex structure of the glomerulus and the glomerular filtration barrier. The next generation of in vitro glomerular models must be suitable for high(er)-content or/and high(er)-throughput screening to enable continuous and systematic monitoring. Moreover, coupling of glomerular or kidney models with those of other organs is a promising approach to enable modelling of partial or full-body responses to drugs and prediction of therapeutic outcomes.
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Affiliation(s)
- Marta G Valverde
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, USA
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Department of Pharmaceutical Sciences, Utrecht University, Utrecht, Netherlands
| | - Luis S Mille
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, USA
| | - Kianti P Figler
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, USA
| | - Ernesto Cervantes
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, USA
| | - Vanessa Y Li
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, USA
| | - Joseph V Bonventre
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, USA.
- Division of Renal Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Rosalinde Masereeuw
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Department of Pharmaceutical Sciences, Utrecht University, Utrecht, Netherlands.
| | - Yu Shrike Zhang
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, USA.
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10
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Bennett KM, Baldelomar EJ, Charlton JR. Delivering on the potential of measuring nephron number in the clinic. Nat Rev Nephrol 2022; 18:271-272. [PMID: 35264770 DOI: 10.1038/s41581-022-00560-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Kevin M Bennett
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, MO, USA.
| | - Edwin J Baldelomar
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Jennifer R Charlton
- Division of Nephrology, Department of Pediatrics, University of Virginia, Charlottesville, VA, USA
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11
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Andersen SB, Taghavi I, Kjer HM, Søgaard SB, Gundlach C, Dahl VA, Nielsen MB, Dahl AB, Jensen JA, Sørensen CM. Evaluation of 2D super-resolution ultrasound imaging of the rat renal vasculature using ex vivo micro-computed tomography. Sci Rep 2021; 11:24335. [PMID: 34934089 PMCID: PMC8692475 DOI: 10.1038/s41598-021-03726-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 12/08/2021] [Indexed: 11/29/2022] Open
Abstract
Super-resolution ultrasound imaging (SRUS) enables in vivo microvascular imaging of deeper-lying tissues and organs, such as the kidneys or liver. The technique allows new insights into microvascular anatomy and physiology and the development of disease-related microvascular abnormalities. However, the microvascular anatomy is intricate and challenging to depict with the currently available imaging techniques, and validation of the microvascular structures of deeper-lying organs obtained with SRUS remains difficult. Our study aimed to directly compare the vascular anatomy in two in vivo 2D SRUS images of a Sprague-Dawley rat kidney with ex vivo μCT of the same kidney. Co-registering the SRUS images to the μCT volume revealed visually very similar vascular features of vessels ranging from ~ 100 to 1300 μm in diameter and illustrated a high level of vessel branching complexity captured in the 2D SRUS images. Additionally, it was shown that it is difficult to use μCT data of a whole rat kidney specimen to validate the super-resolution capability of our ultrasound scans, i.e., validating the actual microvasculature of the rat kidney. Lastly, by comparing the two imaging modalities, fundamental challenges for 2D SRUS were demonstrated, including the complexity of projecting a 3D vessel network into 2D. These challenges should be considered when interpreting clinical or preclinical SRUS data in future studies.
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Affiliation(s)
- Sofie Bech Andersen
- Department of Biomedical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark.
- Department of Radiology, Rigshospitalet, 2100, Copenhagen, Denmark.
| | - Iman Taghavi
- Center for Fast Ultrasound Imaging, Department of Health Technology, Technical University of Denmark, 2800, Lyngby, Denmark
| | - Hans Martin Kjer
- Department of Applied Mathematics and Computer Science, Technical University of Denmark, 2800, Lyngby, Denmark
| | - Stinne Byrholdt Søgaard
- Department of Biomedical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
- Department of Radiology, Rigshospitalet, 2100, Copenhagen, Denmark
| | - Carsten Gundlach
- Department of Physics, Technical University of Denmark, 2800, Lyngby, Denmark
| | - Vedrana Andersen Dahl
- Department of Applied Mathematics and Computer Science, Technical University of Denmark, 2800, Lyngby, Denmark
| | - Michael Bachmann Nielsen
- Department of Radiology, Rigshospitalet, 2100, Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Anders Bjorholm Dahl
- Department of Applied Mathematics and Computer Science, Technical University of Denmark, 2800, Lyngby, Denmark
| | - Jørgen Arendt Jensen
- Center for Fast Ultrasound Imaging, Department of Health Technology, Technical University of Denmark, 2800, Lyngby, Denmark
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Montgomery JB, Klein M, Boire JR, Beck C, Häusermann D, Maksimenko A, Hall CJ. Synchrotron CT of an equine digit at the Australian Synchrotron Imaging and Medical Beamline. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:1769-1777. [PMID: 34738930 PMCID: PMC8570209 DOI: 10.1107/s1600577521010493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 10/10/2021] [Indexed: 06/13/2023]
Abstract
Laminitis is an extremely painful and debilitating condition of horses that can affect their athletic ability and even quality of life. The current gold standard for assessment of laminar tissue is histology, which is the only modality that enables detailed visualization of the lamina. Histology requires dissection of the hoof and therefore can only represent one specific time point. The superior spatial and contrast resolution of synchrotron computed tomography (sCT), when compared with readily available imaging modalities, such as radiographs and conventional CT, provides an opportunity for detailed studies of the lamina without the need for hoof dissection and histological assessment. If the resolution of histology can be matched or even approached, dynamic events, such as laminar blood flow, could also be studied on the microscopic tissue level. To investigate this possible application of sCT further, two objectives are presented: (i) to develop a protocol for sCT of an equine digit using cadaver limbs and (ii) to apply the imaging protocol established during (i) for sCT imaging of the vasculature within the foot using an ex vivo perfusion system to deliver the vascular contrast. The hypotheses were that sCT would allow sufficient resolution for detailed visualization to the level of the secondary lamellae and associated capillaries within the equine digit. Synchrotron CT enabled good visualization of the primary lamellae (average length 3.6 mm) and the ex vivo perfusion system was able to deliver vascular contrast agent to the vessels of the lamina. The individual secondary lamellae (average length 0.142 mm) could not be seen in detail, although differentiation between primary and secondary lamellae was achieved. This approaches, but does not yet reach, the current gold standard, histology, for assessment of the lamellae; however, with further refinement of this imaging technique, improved resolution may be accomplished in future studies.
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Affiliation(s)
- J. B. Montgomery
- Department of Large Animal Clinical Sciences, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada
- Division of Biomedical Engineering, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada
| | - M. Klein
- Imaging and Medical Beamline, Australian Synchrotron (ANSTO), Wurundjeri Country, Clayton, VIC 3168, Australia
| | - J. R. Boire
- RMD Engineering Inc., Saskatoon, SK S7K 3J7, Canada
| | - C. Beck
- University of Melbourne, Werribee, VIC 3030, Australia
| | - D. Häusermann
- Imaging and Medical Beamline, Australian Synchrotron (ANSTO), Wurundjeri Country, Clayton, VIC 3168, Australia
| | - A. Maksimenko
- Imaging and Medical Beamline, Australian Synchrotron (ANSTO), Wurundjeri Country, Clayton, VIC 3168, Australia
| | - C. J. Hall
- Imaging and Medical Beamline, Australian Synchrotron (ANSTO), Wurundjeri Country, Clayton, VIC 3168, Australia
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Korin B, Chung JJ, Avraham S, Shaw AS. Preparation of single-cell suspensions of mouse glomeruli for high-throughput analysis. Nat Protoc 2021; 16:4068-4083. [PMID: 34282333 DOI: 10.1038/s41596-021-00578-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 05/27/2021] [Indexed: 02/06/2023]
Abstract
The kidney glomerulus is essential for proper kidney function. Until recently, technical challenges associated with glomerular isolation and subsequent dissolution into single cells have limited the detailed characterization of cells in the glomerulus. Previous techniques of kidney dissociation result in low glomerular cell yield, which limits high-throughput analysis. The ability to efficiently purify glomeruli and digest the tissue into single cells is especially important for single-cell characterization methods. Here, we present a detailed and comprehensive technique for the extraction and preparation of mouse glomerular cells, with high yield and viability. The method includes direct renal perfusion of Dynabeads via the renal artery followed by kidney dissociation and isolation of glomeruli by magnet; these steps provide a high number and purity of isolated glomeruli, which are further dissociated into single cells. The balanced representation of podocytes, mesangial and endothelial cells in single-cell suspensions of mouse glomeruli, and the high cell viability observed, confirm the efficiency of our method. With some practice, the procedure can be done in <3 h (excluding equipment setup and data analysis). This protocol provides a valuable technique for advancing future single-cell-based studies of the glomerulus in health, injury and disease.
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Affiliation(s)
- Ben Korin
- Department of Research Biology, Genentech, South San Francisco, CA, USA
| | - Jun-Jae Chung
- Department of Research Biology, Genentech, South San Francisco, CA, USA
| | - Shimrit Avraham
- Department of Research Biology, Genentech, South San Francisco, CA, USA
| | - Andrey S Shaw
- Department of Research Biology, Genentech, South San Francisco, CA, USA.
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Bennett KM, Baldelomar EJ, Morozov D, Chevalier RL, Charlton JR. New imaging tools to measure nephron number in vivo: opportunities for developmental nephrology. J Dev Orig Health Dis 2021; 12:179-183. [PMID: 31983353 PMCID: PMC8765346 DOI: 10.1017/s204017442000001x] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The mammalian kidney is a complex organ, requiring the concerted function of up to millions of nephrons. The number of nephrons is constant after nephrogenesis during development, and nephron loss over a life span can lead to susceptibility to acute or chronic kidney disease. New technologies are under development to count individual nephrons in the kidney in vivo. This review outlines these technologies and highlights their relevance to studies of human renal development and disease.
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Affiliation(s)
- K M Bennett
- Department of Radiology, Washington University, Saint Louis, MO, USA
| | - E J Baldelomar
- Department of Radiology, Washington University, Saint Louis, MO, USA
| | - D Morozov
- Department of Radiology, Washington University, Saint Louis, MO, USA
| | - R L Chevalier
- Department of Pediatrics, University of Virginia, Charlottesville, VA, USA
| | - J R Charlton
- Department of Pediatrics, University of Virginia, Charlottesville, VA, USA
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Palladino A, Pizzoleo C, Mavaro I, Lucini C, D'Angelo L, de Girolamo P, Attanasio C. A combined morphometric approach to feature mouse kidney vasculature. Ann Anat 2021; 237:151727. [PMID: 33798690 DOI: 10.1016/j.aanat.2021.151727] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/08/2021] [Accepted: 03/10/2021] [Indexed: 10/21/2022]
Abstract
Physiological kidney function is closely related to the state of the vascular network. Disorders, such as capillary rarefaction, predispose to chronic kidney disease (CKD). In this context, deepening of the methodologies for studying the renal vascular network can be of basic importance. To meet this need, numerous animal models and, in parallel, several methods have been developed. In this work we propose a protocol to accurately feature kidney vasculature in mouse, however, the same protocol is suitable to be applied also to other animal models. The approach is multiparametric and mainly based on micro-computed tomography (μCT) technique. Micro-ct allows to study in detail the vascular network of any organ by exploiting the possibility to perfuse the sample with a contrast agent. The proposed protocol provides a fast and reliable method to extract quantitative information from the μCT scan by using only the basic functions of the software supplied by the scanner without any additional analysis. Through iterative cropping of the scanned ROI and calculation of a sample-specific threshold we calculated that the average volume of a female BALB/c kidney of eighth weeks is 147.8 mm3 (5.4%). We also pointed out that the average volume of the vascular network is 4.9% (0.3%). In parallel we performed traditional histological and immunofluorescence techniques to integrate the information gained via μCT and to frame them in the tissue context. Vessel count on histological sections showed a different density in the different regions of the organ parenchyma, in detail, vessel density in the cortex was 19.03 ± 2.51 vessels/ROI while in the medulla it was 10.6 ± 1.7 vessels/ROI and 5.4 ± 1.3 vessels/ROI in the outer and inner medulla, respectively. We then studied vessel distribution in the renal parenchyma which showed that the 55% of vascular component is included in the cortex, the 30% in the outer medulla and the 15% in the inner medulla. Collectively, we propose an integrated approach that can be particularly useful in the preclinical setting to characterize the vasculature of any organ accurately and rapidly.
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Affiliation(s)
- Antonio Palladino
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, 80137 Naples, Italy
| | - Carmela Pizzoleo
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, 80137 Naples, Italy; Center for Advanced Biomaterials for Healthcare, Istituto Italiano di Tecnologia, 80125 Naples, Italy
| | - Isabella Mavaro
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, 80137 Naples, Italy; Center for Advanced Biomaterials for Healthcare, Istituto Italiano di Tecnologia, 80125 Naples, Italy
| | - Carla Lucini
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, 80137 Naples, Italy
| | - Livia D'Angelo
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, 80137 Naples, Italy
| | - Paolo de Girolamo
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, 80137 Naples, Italy
| | - Chiara Attanasio
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, 80137 Naples, Italy; Center for Advanced Biomaterials for Healthcare, Istituto Italiano di Tecnologia, 80125 Naples, Italy.
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Parvin N, Charlton JR, Baldelomar EJ, Derakhshan JJ, Bennett KM. Mapping vascular and glomerular pathology in a rabbit model of neonatal acute kidney injury using MRI. Anat Rec (Hoboken) 2020; 303:2716-2728. [PMID: 32445514 PMCID: PMC7680718 DOI: 10.1002/ar.24419] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 01/30/2020] [Accepted: 03/03/2020] [Indexed: 12/27/2022]
Abstract
Acute kidney injury (AKI) in premature neonates is common due to the administration of life-saving therapies. The impact of AKI on renal morphology and susceptibility to further renal damage is poorly understood. Recent advances in radiological imaging have allowed integration of soft tissue morphology in the intact organ, facilitating a more complete understanding of changes in tissue microstructure associated with pathology. Here, we applied magnetic resonance imaging (MRI) to detect both glomerular and vascular changes in a rabbit model of neonatal AKI, induced by indomethacin and gentamicin. Using combined spin-echo MRI and cationic ferritin enhanced gradient-echo MRI (CFE-MRI), we observed (a) an increased cortical arterial diameter in the AKI cohort compared to healthy controls, and (b) focal loss of vascular density and glomerular loss in a circumferential band ~1 mm from the cortical surface. This combined use of vascular and glomerular imaging may give insight into the etiology of AKI and its impact on renal health later in life.
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Affiliation(s)
- Neda Parvin
- Department of Radiology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Jennifer R Charlton
- University of Virginia Children's Hospital, Department of Pediatrics, Charlottesville, Virginia, USA
| | - Edwin J Baldelomar
- Department of Radiology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Jamal J Derakhshan
- Department of Radiology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Kevin M Bennett
- Department of Radiology, Washington University in St. Louis, St. Louis, Missouri, USA
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A Stereological Study of the Toxic Effects of Cerium Oxide during Pregnancy on Kidney Tissues in Neonatal NMRI Mice. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:9132724. [PMID: 32685101 PMCID: PMC7330649 DOI: 10.1155/2020/9132724] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 04/27/2020] [Accepted: 06/02/2020] [Indexed: 12/24/2022]
Abstract
Background Both antioxidant and prooxidant activities have been previously reported for cerium oxide (CeO2). The aim of this study was to investigate the effects of CeO2 at different doses on changes in kidney tissues and markers in neonatal mice. Methods We randomly divided 30 pregnant NMRI mice into five groups (n = 6 per group)-a control group and four groups treated with intraperitoneal (i.p.) administration of different doses of CeO2 (10, 25, 80, or 250 mg/kg body weight (bw)) on gestation days (GD) 7 and GD14. At the end of the treatment period, we analyzed the kidney tissues and serum samples. The levels of two serum redox markers, malondialdehyde (MDA) and ferric reducing/antioxidant power (FRAP), were determined. Data were analyzed using one-way ANOVA and Tukey's test, and a P value of <0.05 was considered significant. Results The mean total volumes of the renal corpuscle, glomeruli, and Bowman's capsule membranes significantly increased, and there was a significant decrease in the mean total volume of Bowman's space in the high-dose CeO2 group compared to that in the control group. No statistically significant differences existed in the serum levels of MDA and FRAP in the treated and control groups. Conclusion Our results suggest that high doses of CeO2 impair fetal renal development in pregnant mice, which results in kidney damage. Therefore, CeO2 administration during pregnancy could have dose-dependent adverse effects on the developing kidneys in neonates.
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Abstract
PURPOSE OF REVIEW Many studies have suggested low nephron endowment at birth contributes to the risk of developing hypertension and chronic kidney disease (CKD) later in life. Loss of nephrons with age and disease is largely a subclinical process. New technologies are needed to count nephrons as glomerular filtration rate (GFR) is a poor surrogate for nephron number. RECENT FINDINGS Cortical volume, glomerular density, and percent globally sclerotic glomeruli are imperfect surrogates for nephron number. The disector-fractionator method is the most accurate method to count nephrons but is limited to autopsy settings. Glomerular density combined with kidney imaging and ultrafiltration coefficient-based methods require a kidney biopsy, and have been applied in living humans (kidney donors). Low nephron number predicts a higher postdonation urine albumin. Contrast-enhanced MRI has detected glomeruli without a biopsy, but so far, not in living humans. SUMMARY Currently, there is no accurate and well tolerated method for determining nephron number in living humans. A clinically useful method may allow GFR to be replaced by its more relevant determinants: nephron number and single nephron GFR. This could revolutionize nephrology by separating the measurement of chronic disease (nephron loss) from more reversible hemodynamic effects (nephron hyperfiltration/hypofiltration).
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GHT based automatic kidney image segmentation using modified AAM and GBDT. HEALTH AND TECHNOLOGY 2020. [DOI: 10.1007/s12553-019-00297-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Novel multimodal MRI and MicroCT imaging approach to quantify angiogenesis and 3D vascular architecture of biomaterials. Sci Rep 2019; 9:19474. [PMID: 31857617 PMCID: PMC6923434 DOI: 10.1038/s41598-019-55411-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 11/27/2019] [Indexed: 12/11/2022] Open
Abstract
Quantitative assessment of functional perfusion capacity and vessel architecture is critical when validating biomaterials for regenerative medicine purposes and requires high-tech analytical methods. Here, combining two clinically relevant imaging techniques, (magnetic resonance imaging; MRI and microcomputed tomography; MicroCT) and using the chorioallantoic membrane (CAM) assay, we present and validate a novel functional and morphological three-dimensional (3D) analysis strategy to study neovascularization in biomaterials relevant for bone regeneration. Using our new pump-assisted approach, the two scaffolds, Optimaix (laminar structure mimicking entities of the diaphysis) and DegraPol (highly porous resembling spongy bone), were shown to directly affect the architecture of the ingrowing neovasculature. Perfusion capacity (MRI) and total vessel volume (MicroCT) strongly correlated for both biomaterials, suggesting that our approach allows for a comprehensive evaluation of the vascularization pattern and efficiency of biomaterials. Being compliant with the 3R-principles (replacement, reduction and refinement), the well-established and easy-to-handle CAM model offers many advantages such as low costs, immune-incompetence and short experimental times with high-grade read-outs when compared to conventional animal models. Therefore, combined with our imaging-guided approach it represents a powerful tool to study angiogenesis in biomaterials.
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Denic A, Ricaurte L, Lopez CL, Narasimhan R, Lerman LO, Lieske JC, Thompson RH, Kremers WK, Rule AD. Glomerular Volume and Glomerulosclerosis at Different Depths within the Human Kidney. J Am Soc Nephrol 2019; 30:1471-1480. [PMID: 31278193 DOI: 10.1681/asn.2019020183] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 05/21/2019] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Age, CKD risk factors, and kidney function are associated with larger glomerular volume and a higher percentage of globally sclerotic glomeruli. Knowledge of how these associations may differ by cortical depth is limited. METHODS To investigate glomerular volume and glomerulosclerosis across different depths of cortex, we studied wedge sections of the renal parenchyma from 812 patients who underwent a radical nephrectomy (for a tumor), separately characterizing glomeruli in the superficial (subcapsular), middle, and deep (juxtamedullary) regions. We compared the association of mean nonsclerotic glomerular volume and of glomerulosclerosis (measured as the percentage of globally sclerotic glomeruli) with age, obesity, diabetes, smoking, kidney function, and structural pathology in the superficial, middle, and deep regions. RESULTS The superficial, middle, and deep regions showed significant differences in glomerular volume (0.0025, 0.0031, and 0.0028 µm3, respectively) and in glomerulosclerosis (18%, 7%, and 11%, respectively). There was a marked increase in glomerulosclerosis with age in the superficial region, but larger glomerular volume was not associated with age at any cortical depth. Glomerulosclerosis associated more strongly with arteriosclerosis and ischemic-appearing glomeruli in the superficial region. Hypertension, lower eGFR, and interstitial fibrosis associated with glomerulosclerosis and glomerular volume to a similar extent at any depth. Diabetes and proteinuria more strongly associated with glomerulosclerosis in the deep and middle regions, respectively, but neither associated with glomerular volume differently by depth. Obesity associated more strongly with glomerular volume in the superficial cortex. CONCLUSIONS Most clinical characteristic show similar associations with glomerulosclerosis and glomerulomegaly at different cortical depths. Exceptions include age-related glomerulosclerosis, which appears to be an ischemic process and is more predominant in the superficial region.
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Affiliation(s)
| | | | | | | | | | - John C Lieske
- Division of Nephrology and Hypertension.,Department of Laboratory Medicine and Pathology
| | | | | | - Andrew D Rule
- Division of Nephrology and Hypertension, .,Division of Epidemiology, Mayo Clinic, Rochester, Minnesota
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