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Eissa L, Elhassan MMO, Ismail HI, Ali HA. The ultrastructure of peroxisomes in the kidney of the camel (Camelus dromedarius). Anat Histol Embryol 2024; 53:e13103. [PMID: 39155839 DOI: 10.1111/ahe.13103] [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: 02/01/2024] [Revised: 07/09/2024] [Accepted: 08/06/2024] [Indexed: 08/20/2024]
Abstract
Dromedary camels can survive and reproduce in desert areas. The unique anatomical structure of the kidney enables the camel to prevent water loss. The present study aimed to investigate the ultrastructure of the peroxisomes in the normal kidney of the adult dromedary camel. Tissue samples were taken from the cortex and outer medulla of the kidney of eight camels. The samples were then processed for histological and ultrastructural investigations. The epithelial cells of the proximal tubules displayed peroxisomes with varying sizes and shapes. The peroxisomes were observed in either dispersed or clustered arrangement. Each peroxisome exhibited a homogenous matrix enveloped by a single membrane. Several peroxisomes exhibited one or more dark marginal plates that were always strongly associated with the smooth endoplasmic reticulum. The intensity of the peroxisomal matrix differed significantly, either within the same cell or across different cells. The intensity was light or dark, with a few peroxisomes presenting a similar intensity to that of the mitochondria. Some peroxisomes contained nucleoids within their matrix. The peroxisomes in the first and second sections of proximal convoluted tubules were scattered and primarily located in the region between the microvilli and the underlying mitochondria. The peroxisomes in the third region were abundant and frequently aggregated in clusters throughout the cytoplasm. In the fourth region, the number of peroxisomes was low. The proximal straight tubule had a limited quantity of peroxisomes. In conclusion, peroxisomes in the proximal tubule in kidney of normal dromedary camel were similar in shape and size to other mammals; however, heterogeneity exists as a result of differences in species-specific peroxisomal proteins. Peroxisomes are suggested to be a major source of metabolic energy and act as hydrogen peroxide (H2O2) scavengers, resulting in the release of water and oxygen.
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Affiliation(s)
- Lemiaa Eissa
- Department of Anatomy, College of Veterinary Medicine, University of Bahri, Khartoum, Sudan
| | - Mortada M O Elhassan
- Department of Anatomy, College of Veterinary Medicine, University of Bahri, Khartoum, Sudan
| | - Haider I Ismail
- Department of Anatomy, College of Veterinary Medicine, University of Bahri, Khartoum, Sudan
| | - Hassan A Ali
- Department of Biomedical Sciences, College of Veterinary Medicine, Sudan University of Science and Technology, Khartoum, Sudan
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Damir HA, Ali MA, Adem MA, Amir N, Ali OM, Tariq S, Adeghate E, Greenwood MP, Lin P, Alvira-Iraizoz F, Gillard B, Murphy D, Adem A. Effects of long-term dehydration and quick rehydration on the camel kidney: pathological changes and modulation of the expression of solute carrier proteins and aquaporins. BMC Vet Res 2024; 20:367. [PMID: 39148099 PMCID: PMC11328374 DOI: 10.1186/s12917-024-04215-4] [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: 03/26/2024] [Accepted: 07/31/2024] [Indexed: 08/17/2024] Open
Abstract
BACKGROUND Recurrent dehydration causes chronic kidney disease in humans and animal models. The dromedary camel kidney has remarkable capacity to preserve water and solute during long-term dehydration. In this study, we investigated the effects of dehydration and subsequent rehydration in the camel's kidney histology/ultrastructure and changes in aquaporin/solute carrier proteins along with gene expression. RESULTS In light microscopy, dehydration induced few degenerative and necrotic changes in cells of the cortical tubules with unapparent or little effect on medullary cells. The ultrastructural changes encountered in the cortex were infrequent during dehydration and included nuclear chromatin condensation, cytoplasmic vacuolization, mitochondrial swelling, endoplasmic reticulum/ lysosomal degeneration and sometimes cell death. Some mRNA gene expressions involved in cell stability were upregulated by dehydration. Lesions in endothelial capillaries, glomerular membranes and podocyte tertiary processes in dehydrated camels indicated disruption of glomerular filtration barrier which were mostly corrected by rehydration. The changes in proximal tubules brush borders after dehydration, were accompanied by down regulation of ATP1A1 mRNA involved in Na + /K + pump that were corrected by rehydration. The increased serum Na, osmolality and vasopressin were paralleled by modulation in expression level for corresponding SLC genes with net Na retention in cortex which were corrected by rehydration. Medullary collecting ducts and interstitial connective tissue were mostly unaffected during dehydration. CKD, a chronic nephropathy induced by recurrent dehydration in human and animal models and characterized by interstitial fibrosis and glomerular sclerosis, were not observed in the dehydrated/rehydrated camel kidneys. The initiating factors, endogenous fructose, AVP/AVPR2 and uric acid levels were not much affected. TGF-β1 protein and TGF-β1gene expression showed no changes by dehydration in cortex/medulla to mediate fibrosis. KCNN4 gene expression level was hardly detected in the dehydrated camel's kidney; to encode for Ca + + -gated KCa3.1 channel for Ca + + influx to instigate TGF-β1. Modulation of AQP 1, 2, 3, 4, 9 and SLC protein and/or mRNAs expression levels during dehydration/rehydration was reported. CONCLUSIONS Long-term dehydration induces reversible or irreversible ultrastructural changes in kidney cortex with minor effects in medulla. Modulation of AQP channels, SLC and their mRNAs expression levels during dehydration/rehydration have a role in water conservation. Cortex and medulla respond differently to dehydration/rehydration.
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Affiliation(s)
- Hassan Abu Damir
- Department of Pharmacology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Mahmoud A Ali
- Department of Pharmacology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Muna A Adem
- Department of Pharmacology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Naheed Amir
- Department of Pharmacology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Osman M Ali
- Department of Pharmacology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Saeed Tariq
- Department of Anatomy, College of Medicine & Health Sciences, Emirates University, Al-Ain, United Arab Emirates
| | - Ernest Adeghate
- Department of Anatomy, College of Medicine & Health Sciences, Emirates University, Al-Ain, United Arab Emirates
| | - Michael P Greenwood
- Molecular Neuroendocrinology Research Group, Bristol Medical School, Translational Health Sciences, University of Bristol, Dorothy Hodgkin Building, Bristol, BS13NY, UK
| | - Panjiao Lin
- Molecular Neuroendocrinology Research Group, Bristol Medical School, Translational Health Sciences, University of Bristol, Dorothy Hodgkin Building, Bristol, BS13NY, UK
| | - Fernando Alvira-Iraizoz
- Molecular Neuroendocrinology Research Group, Bristol Medical School, Translational Health Sciences, University of Bristol, Dorothy Hodgkin Building, Bristol, BS13NY, UK
| | - Benjamin Gillard
- Molecular Neuroendocrinology Research Group, Bristol Medical School, Translational Health Sciences, University of Bristol, Dorothy Hodgkin Building, Bristol, BS13NY, UK
| | - David Murphy
- Molecular Neuroendocrinology Research Group, Bristol Medical School, Translational Health Sciences, University of Bristol, Dorothy Hodgkin Building, Bristol, BS13NY, UK.
| | - Abdu Adem
- Department of Pharmacology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
- Department of Pharmacology, College of Medicine and Health Sciences, Khalifa University, PO. Box 127788, Abu Dhabi, UAE.
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Alghamdi M, Chen JF, Jungbluth A, Koutzaki S, Palmer MB, Al-Ahmadie HA, Fine SW, Gopalan A, Sarungbam J, Sirintrapun SJ, Tickoo SK, Reuter VE, Chen YB. L1 Cell Adhesion Molecule (L1CAM) Expression and Molecular Alterations Distinguish Low-Grade Oncocytic Tumor From Eosinophilic Chromophobe Renal Cell Carcinoma. Mod Pathol 2024; 37:100467. [PMID: 38460672 PMCID: PMC11102321 DOI: 10.1016/j.modpat.2024.100467] [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: 11/06/2023] [Revised: 02/06/2024] [Accepted: 03/01/2024] [Indexed: 03/11/2024]
Abstract
Renal low-grade oncocytic tumor (LOT) is a recently recognized renal cell neoplasm designated within the "other oncocytic tumors" category in the 2022 World Health Organization classification system. Although the clinicopathologic, immunohistochemical, and molecular features reported for LOT have been largely consistent, the data are relatively limited. The morphologic overlap between LOT and other low-grade oncocytic neoplasms, particularly eosinophilic chromophobe renal cell carcinoma (E-chRCC), remains a controversial area in renal tumor classification. To address this uncertainty, we characterized and compared large cohorts of LOT (n = 67) and E-chRCC (n = 69) and revealed notable differences between the 2 entities. Clinically, LOT predominantly affected women, whereas E-chRCC showed a male predilection. Histologically, although almost all LOTs were dominated by a small-nested pattern, E-chRCC mainly showed solid and tubular architectures. Molecular analysis revealed that 87% of LOT cases harbored mutations in the tuberous sclerosis complex (TSC)-mTOR complex 1 (mTORC1) pathway, most frequently in MTOR and RHEB genes; a subset of LOT cases had chromosomal 7 and 19q gains. In contrast, E-chRCC lacked mTORC1 mutations, and 60% of cases displayed chromosomal losses characteristic of chRCC. We also explored the cell of origin for LOT and identified L1 cell adhesion molecule (L1CAM), a collecting duct and connecting tubule principal cell marker, as a highly sensitive and specific ancillary test for differentiating LOT from E-chRCC. This distinctive L1CAM immunohistochemical labeling suggests the principal cells as the cell of origin for LOT, unlike the intercalated cell origin of E-chRCC and oncocytoma. The ultrastructural analysis of LOT showed normal-appearing mitochondria and intracytoplasmic lumina with microvilli, different from what has been described for chRCC. Our study further supports LOT as a unique entity with a benign clinical course. Based on the likely cell of origin and its clinicopathologic characteristics, we propose that changing the nomenclature of LOT to "Oncocytic Principal Cell Adenoma of the Kidney" may be a better way to define and describe this entity.
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Affiliation(s)
- Mohammed Alghamdi
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York; Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Jie-Fu Chen
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Achim Jungbluth
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sirma Koutzaki
- Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Matthew B Palmer
- Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Hikmat A Al-Ahmadie
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Samson W Fine
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Anuradha Gopalan
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Judy Sarungbam
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - S Joseph Sirintrapun
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Satish K Tickoo
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Victor E Reuter
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Ying-Bei Chen
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York.
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Schwaderer AL, Rajadhyaksha E, Canas J, Saxena V, Hains DS. Intercalated cell function, kidney innate immunity, and urinary tract infections. Pflugers Arch 2024; 476:565-578. [PMID: 38227050 DOI: 10.1007/s00424-024-02905-4] [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: 09/28/2023] [Revised: 12/22/2023] [Accepted: 01/02/2024] [Indexed: 01/17/2024]
Abstract
Intercalated cells (ICs) in the kidney collecting duct have a versatile role in acid-base and electrolyte regulation along with the host immune defense. Located in the terminal kidney tubule segment, ICs are among the first kidney cells to encounter bacteria when bacteria ascend from the bladder into the kidney. ICs have developed several mechanisms to combat bacterial infections of the kidneys. For example, ICs produce antimicrobial peptides (AMPs), which have direct bactericidal activity, and in many cases are upregulated in response to infections. Some AMP genes with IC-specific kidney expression are multiallelic, and having more copies of the gene confers increased resistance to bacterial infections of the kidney and urinary tract. Similarly, studies in human children demonstrate that those with history of UTIs are more likely to have single-nucleotide polymorphisms in IC-expressed AMP genes that impair the AMP's bactericidal activity. In murine models, depleted or impaired ICs result in decreased clearance of bacterial load following transurethral challenge with uropathogenic E. coli. A 2021 study demonstrated that ICs even act as phagocytes and acidify bacteria within phagolysosomes. Several immune signaling pathways have been identified in ICs which may represent future therapeutic targets in managing kidney infections or inflammation. This review's objective is to highlight IC structure and function with an emphasis on current knowledge of IC's diverse innate immune capabilities.
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Affiliation(s)
- Andrew L Schwaderer
- Division of Nephrology, Department of Pediatrics, Indiana University, 699 Riley Hospital Drive, STE 230, Indianapolis, IN, 46202, USA.
| | - Evan Rajadhyaksha
- Division of Nephrology, Department of Pediatrics, Indiana University, 699 Riley Hospital Drive, STE 230, Indianapolis, IN, 46202, USA
| | - Jorge Canas
- Division of Nephrology, Department of Pediatrics, Indiana University, 699 Riley Hospital Drive, STE 230, Indianapolis, IN, 46202, USA
| | - Vijay Saxena
- Division of Nephrology, Department of Pediatrics, Indiana University, 699 Riley Hospital Drive, STE 230, Indianapolis, IN, 46202, USA
| | - David S Hains
- Division of Nephrology, Department of Pediatrics, Indiana University, 699 Riley Hospital Drive, STE 230, Indianapolis, IN, 46202, USA
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Wiersma LE, Avramut MC, Koster AJ, van den Berg CW, Rabelink TJ. Ultrastructural characterization of maturing iPSC-derived nephron structures upon transplantation. Microsc Res Tech 2024; 87:495-505. [PMID: 37929605 DOI: 10.1002/jemt.24447] [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: 07/27/2023] [Revised: 09/29/2023] [Accepted: 10/14/2023] [Indexed: 11/07/2023]
Abstract
Pluripotent stem cell-derived kidney organoids hold great promise as a potential auxiliary transplant tissue for individuals with end-stage renal disease and as a platform for studying kidney diseases and drug discovery. To establish accurate models, it is crucial to thoroughly characterize the morphological features and maturation stages of the cellular components within these organoids. Nephrons, the functional units of the kidney, possess distinct morphological structures that directly correlate with their specific functions. High spatial resolution imaging emerges as a powerful technique for capturing ultrastructural details that may go unnoticed with other methods such as immunofluorescent imaging and scRNA sequencing. In our study, we have applied software capable of seamlessly stitching virtual slides generated from electron microscopy, resulting in high-definition overviews of tissue slides. With this technology, we can comprehensively characterize the development and maturation of kidney organoids when transplanted under the renal capsule of mice. These organoids exhibit advanced ultrastructural developments upon transplantation, including the formation of the filtration barrier in the renal corpuscle, the presence of microvilli in the proximal tubule, and various types of cell sub-segmentation in the connecting tubule similarly to those seen in the adult kidney. Such ultrastructural characterization provides invaluable insights into the structural development and functional morphology of nephron segments within kidney organoids and how to advance them by interventions such as a transplantation. Research Highlights High-resolution imaging is crucial to determine morphological maturation of hiPSC-derived kidney organoids. Upon transplantation, refined ultrastructural development of nephron segments was observed, such as the development of the glomerular filtration barrier.
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Affiliation(s)
- L E Wiersma
- Department of Internal Medicine - Nephrology, Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory of Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - M C Avramut
- Department of Internal Medicine - Nephrology, Leiden University Medical Center, Leiden, The Netherlands
- Department of Cell and Chemical Biology - Electron Microscopy Facility, Leiden University Medical Center, Leiden, The Netherlands
| | - A J Koster
- Department of Cell and Chemical Biology - Electron Microscopy Facility, Leiden University Medical Center, Leiden, The Netherlands
| | - C W van den Berg
- Department of Internal Medicine - Nephrology, Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory of Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Leiden University Medical Center, Leiden, The Netherlands
| | - T J Rabelink
- Department of Internal Medicine - Nephrology, Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory of Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Leiden University Medical Center, Leiden, The Netherlands
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Chung DJ, Madison GP, Aponte AM, Singh K, Li Y, Pirooznia M, Bleck CKE, Darmani NA, Balaban RS. Metabolic design in a mammalian model of extreme metabolism, the North American least shrew (Cryptotis parva). J Physiol 2022; 600:547-567. [PMID: 34837710 PMCID: PMC10655134 DOI: 10.1113/jp282153] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 11/19/2021] [Indexed: 01/10/2023] Open
Abstract
Mitochondrial adaptations are fundamental to differentiated function and energetic homeostasis in mammalian cells. But the mechanisms that underlie these relationships remain poorly understood. Here, we investigated organ-specific mitochondrial morphology, connectivity and protein composition in a model of extreme mammalian metabolism, the least shrew (Cryptotis parva). This was achieved through a combination of high-resolution 3D focused ion beam electron microscopy imaging and tandem mass tag mass spectrometry proteomics. We demonstrate that liver and kidney mitochondrial content are equivalent to the heart, permitting assessment of mitochondrial adaptations in different organs with similar metabolic demand. Muscle mitochondrial networks (cardiac and skeletal) are extensive, with a high incidence of nanotunnels - which collectively support the metabolism of large muscle cells. Mitochondrial networks were not detected in the liver and kidney as individual mitochondria are localized with sites of ATP consumption. This configuration is not observed in striated muscle, likely due to a homogeneous ATPase distribution and the structural requirements of contraction. These results demonstrate distinct, fundamental mitochondrial structural adaptations for similar metabolic demand that are dependent on the topology of energy utilization process in a mammalian model of extreme metabolism. KEY POINTS: Least shrews were studied to explore the relationship between metabolic function, mitochondrial morphology and protein content in different tissues. Liver and kidney mitochondrial content and enzymatic activity approaches that of the heart, indicating similar metabolic demand among tissues that contribute to basal and maximum metabolism. This allows an examination of mitochondrial structure and composition in tissues with similar maximum metabolic demands. Mitochondrial networks only occur in striated muscle. In contrast, the liver and kidney maintain individual mitochondria with limited reticulation. Muscle mitochondrial reticulation is the result of dense ATPase activity and cell-spanning myofibrils which require networking for adequate metabolic support. In contrast, liver and kidney ATPase activity is localized to the endoplasmic reticulum and basolateral membrane, respectively, generating a locally balanced energy conversion and utilization. Mitochondrial morphology is not driven by maximum metabolic demand, but by the cytosolic distribution of energy-utilizing systems set by the functions of the tissue.
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Affiliation(s)
- Dillon J. Chung
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Grey P. Madison
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Angel M. Aponte
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Komudi Singh
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Yuesheng Li
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Mehdi Pirooznia
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Christopher K. E. Bleck
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Nissar A. Darmani
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, California, USA
| | - Robert S. Balaban
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
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7
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Marcoux AA, Tremblay LE, Slimani S, Fiola MJ, Mac-Way F, Haydock L, Garneau AP, Isenring P. Anatomophysiology of the Henle's Loop: Emphasis on the Thick Ascending Limb. Compr Physiol 2021; 12:3119-3139. [PMID: 34964111 DOI: 10.1002/cphy.c210021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The loop of Henle plays a variety of important physiological roles through the concerted actions of ion transport systems in both its apical and basolateral membranes. It is involved most notably in extracellular fluid volume and blood pressure regulation as well as Ca2+ , Mg2+ , and acid-base homeostasis because of its ability to reclaim a large fraction of the ultrafiltered solute load. This nephron segment is also involved in urinary concentration by energizing several of the steps that are required to generate a gradient of increasing osmolality from cortex to medulla. Another important role of the loop of Henle is to sustain a process known as tubuloglomerular feedback through the presence of specialized renal tubular cells that lie next to the juxtaglomerular arterioles. This article aims at describing these physiological roles and at discussing a number of the molecular mechanisms involved. It will also report on novel findings and uncertainties regarding the realization of certain processes and on the pathophysiological consequences of perturbed salt handling by the thick ascending limb of the loop of Henle. Since its discovery 150 years ago, the loop of Henle has remained in the spotlight and is now generating further interest because of its role in the renal-sparing effect of SGLT2 inhibitors. © 2022 American Physiological Society. Compr Physiol 12:1-21, 2022.
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Affiliation(s)
- Andrée-Anne Marcoux
- Nephrology Research Group, Department of Medicine, Laval University, Québec, QC, Canada
| | - Laurence E Tremblay
- Nephrology Research Group, Department of Medicine, Laval University, Québec, QC, Canada
| | - Samira Slimani
- Nephrology Research Group, Department of Medicine, Laval University, Québec, QC, Canada
| | - Marie-Jeanne Fiola
- Nephrology Research Group, Department of Medicine, Laval University, Québec, QC, Canada
| | - Fabrice Mac-Way
- Nephrology Research Group, Department of Medicine, Laval University, Québec, QC, Canada
| | - Ludwig Haydock
- Nephrology Research Group, Department of Medicine, Laval University, Québec, QC, Canada
| | - Alexandre P Garneau
- Nephrology Research Group, Department of Medicine, Laval University, Québec, QC, Canada.,Cardiometabolic Axis, School of Kinesiology and Physical Activity Sciences, University of Montréal, Montréal, QC, Canada
| | - Paul Isenring
- Nephrology Research Group, Department of Medicine, Laval University, Québec, QC, Canada
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Shimokawa T, Nakagawa T, Hayashi K, Yamagata M, Yoneda K. Subcellular distribution of α2-adrenoceptor subtypes in the rodent kidney. Cell Tissue Res 2021; 387:303-314. [PMID: 34837110 DOI: 10.1007/s00441-021-03558-w] [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: 04/19/2021] [Accepted: 11/12/2021] [Indexed: 10/19/2022]
Abstract
Renal α2-adrenoceptors have been reported to play a role in the regulation of urinary output, renin secretion, and water and sodium excretion in the kidneys. However, the distribution of α2-adrenoceptor subtypes in the kidneys remains unclear. In this study, we aimed to investigate the localization of α2-adrenoceptor subtypes in rat kidneys using 8-week-old Sprague-Dawley rats. Immunofluorescence imaging revealed that both α2A- and α2B-adrenoceptors were expressed in the basolateral, but not apical, membrane of the epithelial cells of the proximal tubules. We also found that α2A- and α2B-adrenoceptors were not expressed in the glomeruli, collecting ducts, or the descending limb of the loop of Henle and vasa recta. In contrast, α2C-adrenoceptors were found to be localized in the glomeruli and lumen of the cortical and medullary collecting ducts. These results suggest that noradrenaline may act on the basement membrane of the proximal tubules through α2A- and α2B-adrenoceptors. Moreover, noradrenaline may be involved in the regulation of glomerular filtration and proteinuria through the induction of morphological changes in mesangial cells and podocytes via α2C-adrenoceptors. In the collecting ducts, urinary noradrenaline may regulate morphological changes of the microvilli through α2C-adrenoceptors. Our findings provide an immunohistochemical basis for understanding the cellular targets of α2-adrenergic regulation in the kidneys. This may be used to devise therapeutic strategies targeting α2-adrenoceptors.
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Affiliation(s)
- Takaomi Shimokawa
- Laboratory of Clinical Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-kita, Tondabayashi, Osaka, 584-8540, Japan
| | - Toshitaka Nakagawa
- Division of Research Instrument and Equipment, Life Science Research Center, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan
| | - Kohei Hayashi
- Laboratory of Clinical Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-kita, Tondabayashi, Osaka, 584-8540, Japan
| | - Masayo Yamagata
- Laboratory of Clinical Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-kita, Tondabayashi, Osaka, 584-8540, Japan
| | - Kozo Yoneda
- Laboratory of Clinical Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, 3-11-1 Nishikiori-kita, Tondabayashi, Osaka, 584-8540, Japan.
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9
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Cadherin puncta are interdigitated dynamic actin protrusions necessary for stable cadherin adhesion. Proc Natl Acad Sci U S A 2021; 118:2023510118. [PMID: 34099568 DOI: 10.1073/pnas.2023510118] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cadherins harness the actin cytoskeleton to build cohesive sheets of cells using paradoxically weak bonds, but the molecular mechanisms are poorly understood. In one popular model, actin organizes cadherins into large, micrometer-sized clusters known as puncta. Myosin is thought to pull on these puncta to generate strong adhesion. Here, however, we show that cadherin puncta are actually interdigitated actin microspikes generated by actin polymerization mediated by three factors (Arp2/3, EVL, and CRMP-1). The convoluted membranes in these regions give the impression of cadherin clustering by fluorescence microscopy, but the ratio of cadherin to membrane is constant. Nevertheless, these interlocking fingers of membrane are important for adhesion because perturbing their formation disrupts cell adhesion. In contrast, blocking myosin-dependent contractility does not disrupt either the interdigitated microspikes or lateral membrane adhesion. "Puncta" are zones of strong cell-cell adhesion not due to cadherin clustering but that occur because the interdigitated microspikes expand the surface area available for adhesive bond formation and increase the asperity of the cell surface to promote friction between cells.
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10
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Saxena V, Gao H, Arregui S, Zollman A, Kamocka MM, Xuei X, McGuire P, Hutchens M, Hato T, Hains DS, Schwaderer AL. Kidney intercalated cells are phagocytic and acidify internalized uropathogenic Escherichia coli. Nat Commun 2021; 12:2405. [PMID: 33893305 PMCID: PMC8065053 DOI: 10.1038/s41467-021-22672-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 03/18/2021] [Indexed: 02/02/2023] Open
Abstract
Kidney intercalated cells are involved in acid-base homeostasis via vacuolar ATPase expression. Here we report six human intercalated cell subtypes, including hybrid principal-intercalated cells identified from single cell transcriptomics. Phagosome maturation is a biological process that increases in biological pathway analysis rank following exposure to uropathogenic Escherichia coli in two of the intercalated cell subtypes. Real time confocal microscopy visualization of murine renal tubules perfused with green fluorescent protein expressing Escherichia coli or pHrodo Green E. coli BioParticles demonstrates that intercalated cells actively phagocytose bacteria then acidify phagolysosomes. Additionally, intercalated cells have increased vacuolar ATPase expression following in vivo experimental UTI. Taken together, intercalated cells exhibit a transcriptional response conducive to the kidney's defense, engulf bacteria and acidify the internalized bacteria. Intercalated cells represent an epithelial cell with characteristics of professional phagocytes like macrophages.
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Affiliation(s)
- Vijay Saxena
- Indiana University School of Medicine, Department of Pediatrics, Division of Nephrology, Indianapolis, IN, USA.
| | - Hongyu Gao
- Indiana University School of Medicine, Department of Medical & Molecular Genetics, Indianapolis, IN, USA
| | - Samuel Arregui
- Indiana University School of Medicine, Department of Pediatrics, Division of Nephrology, Indianapolis, IN, USA
| | - Amy Zollman
- Indiana University School of Medicine, Department of Medicine, Division of Nephrology, Indianapolis, IN, USA
| | - Malgorzata Maria Kamocka
- Indiana University School of Medicine, Department of Medicine, Division of Nephrology, Indianapolis, IN, USA
| | - Xiaoling Xuei
- Indiana University School of Medicine, Department of Medical & Molecular Genetics, Indianapolis, IN, USA
| | - Patrick McGuire
- Indiana University School of Medicine, Department of Medical & Molecular Genetics, Indianapolis, IN, USA
| | - Michael Hutchens
- Oregon Health and Science University, Department of Anesthesiology & Perioperative Medicine, Portland, OR, USA
| | - Takashi Hato
- Indiana University School of Medicine, Department of Medicine, Division of Nephrology, Indianapolis, IN, USA
| | - David S Hains
- Indiana University School of Medicine, Department of Pediatrics, Division of Nephrology, Indianapolis, IN, USA
| | - Andrew L Schwaderer
- Indiana University School of Medicine, Department of Pediatrics, Division of Nephrology, Indianapolis, IN, USA.
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11
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Zheleznova NN, Kumar V, Kurth T, Cowley AW. Hydrogen peroxide (H 2O 2) mediated activation of mTORC2 increases intracellular Na + concentration in the renal medullary thick ascending limb of Henle. Sci Rep 2021; 11:7300. [PMID: 33790341 PMCID: PMC8012714 DOI: 10.1038/s41598-021-86678-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 03/05/2021] [Indexed: 11/22/2022] Open
Abstract
Hydrogen peroxide (H2O2) production in the renal outer medulla is an important determinant of renal medullary blood flow and blood pressure (BP) salt-sensitivity in Dahl salt-sensitive (SS) rats. The mechanisms and pathways responsible for these actions are poorly understood. Recently, we have discovered that the mTOR complex 2 (mTORC2) plays a critical role in BP salt-sensitivity of SS rats by regulating Na+ homeostasis. PP242, an inhibitor of mTORC1/2 pathways exhibits potent natriuretic actions and completely prevented salt-induced hypertension in SS rats. In the present study, we have found that chronic infusion of H2O2 into the single remaining kidney of Sprague Dawley (SD) rats (3 days) stimulated the functional marker (pAKTSer473/AKT) of mTORC2 activity measured by Western Blot analysis. No changes in mTORC1 activity in OM were observed as determined by pS6Ser235/236/S6. Using fluorescent microscopy and the Na+ sensitive dye Sodium Green, we have shown that H2O2 (100 µM added in the bath) increased intracellular sodium concentration ([Na+]i) in renal medullary thick ascending limbs (mTALs) isolated from SD rats. These responses were almost completely abolished by pretreatment of mTAL with 10 µM PP242, indicating that mTORC1/2 pathways were involved in the H2O2 induced increase of [Na+]i. mTAL cell volume remained unchanged (± 1%) by H2O2 as determined by 3D reconstruction confocal laser scanning microscopy techniques. Consistent with the microscopy data, Western Blot analysis of proteins obtained from freshly isolated mTAL treated with 100 µM H2O2 exhibited increased activity/phosphorylation of AKT (pAKTSer473/AKT) that was inhibited by PP242. This was associated with increased protein activity of the apical membrane cotransporter Na+-K+-2Cl- (NKCC2) and the Na/H exchanger (NHE-3). Na+-K+-ATPase activity was increased as reflected an increase in the ratio of pNa+-K+-ATPaseSer16 to total Na+-K+-ATPase. Overall, the results indicate that H2O2 mediated activation of mTORC2 plays a key role in transducing the observed increases of cytosolic [Na+]i despite associated increases of basolateral pump activity.
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Affiliation(s)
- Nadezhda N Zheleznova
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI, 53226, USA.
| | - Vikash Kumar
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI, 53226, USA
| | - Theresa Kurth
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI, 53226, USA
| | - Allen W Cowley
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI, 53226, USA.
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12
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Ali MA, Abu Damir H, Ali OM, Amir N, Tariq S, Greenwood MP, Lin P, Gillard B, Murphy D, Adem A. The effect of long-term dehydration and subsequent rehydration on markers of inflammation, oxidative stress and apoptosis in the camel kidney. BMC Vet Res 2020; 16:458. [PMID: 33228660 PMCID: PMC7686779 DOI: 10.1186/s12917-020-02628-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 10/19/2020] [Indexed: 12/24/2022] Open
Abstract
Background Dehydration has deleterious effects in many species, but camels tolerate long periods of water deprivation without serious health compromise. The kidney plays crucial role in water conservation, however, some reports point to elevated kidney function tests in dehydrated camels. In this work, we investigated the effects of dehydration and rehydration on kidney cortex and medulla with respect to pro-inflammatory markers, oxidative stress and apoptosis along with corresponding gene expression. Results The cytokines IL-1β and IL-18 levels were significantly elevated in the kidney cortex of dehydrated camel, possibly expressed by tubular epithelium, podocytes and/or mesangial cells. Elevation of IL-18 persisted after rehydration. Dehydration induced oxidative stress in kidney cortex evident by significant increases in MDA and GSH, but significant decreases in SOD and CAT. In the medulla, CAT decreased significantly, but MDA, GSH and SOD levels were not affected. Rehydration abolished the oxidative stress. In parallel with the increased levels of MDA, we observed increased levels of PTGS1 mRNA, in MDA synthesis pathway. GCLC mRNA expression level, involved in GSH synthesis, was upregulated in kidney cortex by rehydration. However, both SOD1 and SOD3 mRNA levels dropped, in parallel with SOD activity, in the cortex by dehydration. There were significant increases in caspases 3 and 9, p53 and PARP1, indicating apoptosis was triggered by intrinsic pathway. Expression of BCL2l1 mRNA levels, encoding for BCL-xL, was down regulated by dehydration in cortex. CASP3 expression level increased significantly in medulla by dehydration and continued after rehydration whereas TP53 expression increased in cortex by rehydration. Changes in caspase 8 and TNF-α were negligible to instigate extrinsic apoptotic trail. Generally, apoptotic markers were extremely variable after rehydration indicating that animals did not fully recover within three days. Conclusions Dehydration causes oxidative stress in kidney cortex and apoptosis in cortex and medulla. Kidney cortex and medulla were not homogeneous in all parameters investigated indicating different response to dehydration/rehydration. Some changes in tested parameters directly correlate with alteration in steady-state mRNA levels.
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Affiliation(s)
- Mahmoud A Ali
- Department of Pharmacology, CollegeofMedicine&HealthSciences, United Arab Emirates University, Al- Ain, United Arab Emirates
| | - Hassan Abu Damir
- Department of Pharmacology, CollegeofMedicine&HealthSciences, United Arab Emirates University, Al- Ain, United Arab Emirates
| | - Osman M Ali
- College of Medicine and Public Health, Flinders University, Adelaide, Australia
| | - Naheed Amir
- Department of Pharmacology, CollegeofMedicine&HealthSciences, United Arab Emirates University, Al- Ain, United Arab Emirates
| | - Saeed Tariq
- Department of Anatomy, CollegeofMedicine&HealthSciences, Emirates University, Al-Ain, United Arab Emirates
| | - Michael P Greenwood
- Molecular Neuroendocrinology Research Group, Bristol Medical School, Translational Health Sciences, University of Bristol, Dorothy Hodgkin Building, Bristol, BS13NY, UK
| | - Panjiao Lin
- Molecular Neuroendocrinology Research Group, Bristol Medical School, Translational Health Sciences, University of Bristol, Dorothy Hodgkin Building, Bristol, BS13NY, UK
| | - Benjamin Gillard
- Molecular Neuroendocrinology Research Group, Bristol Medical School, Translational Health Sciences, University of Bristol, Dorothy Hodgkin Building, Bristol, BS13NY, UK
| | - David Murphy
- Molecular Neuroendocrinology Research Group, Bristol Medical School, Translational Health Sciences, University of Bristol, Dorothy Hodgkin Building, Bristol, BS13NY, UK.
| | - Abdu Adem
- Department of Pharmacology, CollegeofMedicine&HealthSciences, United Arab Emirates University, Al- Ain, United Arab Emirates. .,Department of Pharmacology, College of Medicine and Health Sciences, Khalifa University, P.O.Box 127788, Abu Dhabi, UAE.
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13
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Mihevc M, Petreski T, Maver U, Bevc S. Renal proximal tubular epithelial cells: review of isolation, characterization, and culturing techniques. Mol Biol Rep 2020; 47:9865-9882. [PMID: 33170426 DOI: 10.1007/s11033-020-05977-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 11/03/2020] [Indexed: 12/23/2022]
Abstract
The kidney is a complex organ, comprised primarily of glomerular, tubular, mesangial, and endothelial cells, and podocytes. The fact that renal cells are terminally differentiated at 34 weeks of gestation is the main obstacle in regeneration and treatment of acute kidney injury or chronic kidney disease. Furthermore, the number of chronic kidney disease patients is ever increasing and with it the medical community should aim to improve existing and develop new methods of renal replacement therapy. On the other hand, as polypharmacy is on the rise, thought should be given into developing new ways of testing drug safety. A possible way to tackle these issues is with isolation and culture of renal cells. Several protocols are currently described to isolate the desired cells, of which the most isolated are the proximal tubular epithelial cells. They play a major role in water homeostasis, acid-base control, reabsorption of compounds, and secretion of xenobiotics and endogenous metabolites. When exposed to ischemic, toxic, septic, or obstructive conditions their death results in what we clinically perceive as acute kidney injury. Additionally, due to renal cells' limited regenerative potential, the profibrotic environment inevitably leads to chronic kidney disease. In this review we will focus on human proximal tubular epithelial cells. We will cover human kidney culture models, cell sources, isolation, culture, immortalization, and characterization subdivided into morphological, phenotypical, and functional characterization.
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Affiliation(s)
- Matic Mihevc
- Department of Nephrology, Clinic for Internal Medicine, University Medical Centre Maribor, Ljubljanska ulica 5, 2000, Maribor, Slovenia
| | - Tadej Petreski
- Department of Nephrology, Clinic for Internal Medicine, University Medical Centre Maribor, Ljubljanska ulica 5, 2000, Maribor, Slovenia
- Faculty of Medicine, Institute of Biomedical Sciences, University of Maribor, Taborska ulica 8, 2000, Maribor, Slovenia
| | - Uroš Maver
- Faculty of Medicine, Institute of Biomedical Sciences, University of Maribor, Taborska ulica 8, 2000, Maribor, Slovenia.
- Department of Pharmacology, Faculty of Medicine, University of Maribor, Taborska ulica 8, 2000, Maribor, Slovenia.
| | - Sebastjan Bevc
- Department of Nephrology, Clinic for Internal Medicine, University Medical Centre Maribor, Ljubljanska ulica 5, 2000, Maribor, Slovenia.
- Department of Pharmacology, Faculty of Medicine, University of Maribor, Taborska ulica 8, 2000, Maribor, Slovenia.
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14
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Love H, Evans R, Humes HD, Roy S, Zent R, Harris R, Wilson M, Fissell WH. Metformin and Inhibition of Transforming Growth Factor-Beta Stimulate In Vitro Transport in Primary Renal Tubule Cells. Tissue Eng Part A 2020; 26:1091-1098. [PMID: 32312181 DOI: 10.1089/ten.tea.2019.0294] [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: 11/13/2022] Open
Abstract
Patient-oriented applications of cell culture include cell therapy of organ failure like chronic renal failure. Clinical deployment of a cell-based device for artificial renal replacement requires qualitative and quantitative fidelity of a cultured cell to its in vivo counterpart. Active specific apicobasal ion transport reabsorbs 90-99% of the filtered load of salt and water in the kidney. In a bioengineered kidney, tubular transport concentrates wastes and eliminates the need for hemodialysis, but renal tubule cells in culture transport little or no salt and water. We previously identified transforming growth factor-beta as a signaling pathway necessary for in vitro differentiation of renal tubule cells. Inhibition of TGF-β receptor-1 led to active inhabitable electrolyte and water transport by primary human renal tubule epithelial cells in vitro. Addition of metformin increased transport, in the context of a transient effect on 5' AMP-activated kinase phosphorylation. The signals that undermine in vitro differentiation are complex, but susceptible to pharmacologic intervention. This achievement overcomes a major hurdle limiting the development of a bioreactor of cultured cells for renal replacement therapy that encompasses not only endocrine and metabolic functions but also transport and excretion. Impact statement Clinical tissue engineering requires functional fidelity of the cultured cell to its in vivo counterpart, but this has been elusive in renal tissue engineering. Typically, renal tubule cells in culture have a flattened morphology and do not express key transporters essential to their function. In this study, we build on our prior work by using small molecules to modulate pathways affected by substrate elasticity. In doing so, we are able to enhance differentiation of these cells on conventional noncompliant substrates and show transport. These results are fundamentally enabling a new generation of cell-based renal therapies.
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Affiliation(s)
- Harold Love
- Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Rachel Evans
- Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | | | - Shuvo Roy
- Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California, USA
| | - Roy Zent
- Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Medicine, Veterans Affairs Medical Center, Nashville, Tennessee, USA
| | - Raymond Harris
- Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Medicine, Veterans Affairs Medical Center, Nashville, Tennessee, USA
| | - Matthew Wilson
- Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Medicine, Veterans Affairs Medical Center, Nashville, Tennessee, USA
| | - William Henry Fissell
- Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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15
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Burnstock G, Loesch A. Sympathetic innervation of the kidney in health and disease: Emphasis on the role of purinergic cotransmission. Auton Neurosci 2017; 204:4-16. [DOI: 10.1016/j.autneu.2016.05.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 05/27/2016] [Accepted: 05/29/2016] [Indexed: 11/29/2022]
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16
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Silva SCT, de Almeida LA, Soares S, Grossi MF, Valente AMS, Tagliati CA. In vitro study of putative genomic biomarkers of nephrotoxicity through differential gene expression using gentamicin. Toxicol Mech Methods 2017; 27:435-441. [PMID: 28372472 DOI: 10.1080/15376516.2017.1313345] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Drug-induced nephrotoxicity is one of the most frequently observed effects in long-term pharmacotherapy. The effects of nephrotoxicity are commonly discovered later due to a lack of sensitivity in in vivo methods. Therefore, researchers have tried to develop in vitro alternative methods for early identification of toxicity. In this study, LLC-PK1 cells were exposed to gentamicin through MTT and trypan blue assay. Concentrations of 4 (low), 8 (medium) and 12 (high) mM, were used to evaluate differential gene expression. A panel of genes was selected based on gene expression changes. The search for sequences of mRNA encoding proteins previously associated with kidney damage was conducted in the databases of the National Center for Biotechnology Information (USA). RNA was extracted from the cells, and RT-qPCR was performed to evaluate differential expression profiles of the selected genes. Among the 11 analyzed genes, four proved to be differentially up-regulated in cells exposed to gentamicin: HAVcr1, caspase 3, ICAM-1 and EXOC6. According to this study's results, we suggest that these genes play an important role in the mechanism of in vitro nephrotoxicity caused by gentamicin and can be used as early in vitro biomarkers to identify nephrotoxicity when developing safer drugs.
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Affiliation(s)
- Sarah Cristina Teixeira Silva
- a Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, Laboratório de Toxicologia Experimental in vitro , Universidade Federal de Minas Gerais (UFMG) , Belo Horizonte , Brazil
| | - Leonardo Augusto de Almeida
- b Departamento de Microbiologia e Imunologia, Laboratório de Imunologia, Instituto de Ciências Biomédicas , Universidade Federal de Alfenas (UniFal) , Alfenas , Brazil
| | - Stellamaris Soares
- a Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, Laboratório de Toxicologia Experimental in vitro , Universidade Federal de Minas Gerais (UFMG) , Belo Horizonte , Brazil
| | - Marina Felipe Grossi
- a Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, Laboratório de Toxicologia Experimental in vitro , Universidade Federal de Minas Gerais (UFMG) , Belo Horizonte , Brazil
| | - Anete Maria Santana Valente
- c Departamento de Nutrição , Universidade Federal de Juiz de Fora (UFJF) - Campus Governador Valadares , Governador Valadares , Brazil
| | - Carlos Alberto Tagliati
- a Departamento de Análises Clínicas e Toxicológicas, Faculdade de Farmácia, Laboratório de Toxicologia Experimental in vitro , Universidade Federal de Minas Gerais (UFMG) , Belo Horizonte , Brazil
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17
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Khan SR. Histological aspects of the "fixed-particle" model of stone formation: animal studies. Urolithiasis 2016; 45:75-87. [PMID: 27896391 DOI: 10.1007/s00240-016-0949-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 11/22/2016] [Indexed: 01/25/2023]
Abstract
Crystallization by itself is not harmful as long as the crystals are not retained in the kidneys and are allowed to pass freely down the renal tubules to be excreted in the urine. A number of theories have been proposed, and studies performed, to determine the mechanisms involved in crystal retention within the kidneys. It has been suggested that urinary transit through the nephron is too fast for crystals to grow large enough to be retained. Thus, free particle mechanism alone cannot lead to stone formation, and there must be a mechanism for crystal fixation within the kidneys. Animal model studies suggest that crystal retention is possible through both the free- and fixed-particle mechanisms. Crystal-cell interaction leads to pathological changes which promote crystal attachment to either epithelial cells or their basement membrane. Alternatively, crystals aggregate and produce large enough particles to block the tubules particularly at sites, where urinary flow is affected because of changes in the luminal diameter of the tubule. Crystal deposits plugging the openings of the ducts of Bellini may be the result of such a phenomenon. Intratubular crystals translocating to renal interstitium may produce osteogenic changes in the epithelial or endothelial cells resulting in the formation of the Randall's plaques. Thus, fixation appears to be either through the formation of Randall's plugs, crystal plugs clogging the openings of the ducts of Bellini or sub-epithelial crystal deposits, and the Randall's plaques.
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Affiliation(s)
- Saeed R Khan
- Department of Pathology, Immunology and Laboratory Investigation, College of Medicine, University of Florida, Gainesville, FL, USA. .,Department of Urology, College of Medicine, University of Florida, Gainesville, FL, USA.
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18
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Legin AA, Theiner S, Schintlmeister A, Reipert S, Heffeter P, Jakupec MA, Mayr J, Varbanov HP, Kowol CR, Galanski M, Berger W, Wagner M, Keppler BK. Multi-scale imaging of anticancer platinum(iv) compounds in murine tumor and kidney. Chem Sci 2016; 7:3052-3061. [PMID: 29997796 PMCID: PMC6004953 DOI: 10.1039/c5sc04383b] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 12/22/2015] [Indexed: 01/31/2023] Open
Abstract
Nano-scale secondary ion mass spectrometry (NanoSIMS) enables trace element and isotope analyses with high spatial resolution. This unique capability has recently been exploited in several studies analyzing the subcellular distribution of Au and Pt anticancer compounds. However, these studies were restricted to cell culture systems. To explore the applicability to the in vivo setting, we developed a combined imaging approach consisting of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), NanoSIMS and transmission electron microscopy (TEM) suitable for multi-scale detection of the platinum distribution in tissues. Applying this approach to kidney and tumor samples upon administration of selected platinum(iv) anticancer prodrugs revealed uneven platinum distributions on both the organ and subcellular scales. Spatial platinum accumulation patterns were quantitatively assessed by LA-ICP-MS in histologically heterogeneous organs (e.g., higher platinum accumulation in kidney cortex than in medulla) and used to select regions of interest for subcellular-scale imaging with NanoSIMS. These analyses revealed cytoplasmic sulfur-rich organelles accumulating platinum in both kidney and malignant cells. Those in the tumor were subsequently identified as organelles of lysosomal origin, demonstrating the potential of the combinatorial approach for investigating therapeutically relevant drug concentrations on a submicrometer scale.
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Affiliation(s)
- A A Legin
- Institute of Inorganic Chemistry , Research Platform "Translational Cancer Therapy Research," and Research Network "Chemistry meets Microbiology" , University of Vienna , Währinger Straße 42 , A-1090 Vienna , Austria . ; Tel: +43-1-4277-52600
| | - S Theiner
- Institute of Inorganic Chemistry , Research Platform "Translational Cancer Therapy Research," and Research Network "Chemistry meets Microbiology" , University of Vienna , Währinger Straße 42 , A-1090 Vienna , Austria . ; Tel: +43-1-4277-52600
| | - A Schintlmeister
- Department of Microbiology and Ecosystem Science , Research Network "Chemistry meets Microbiology", and Large-Instrument Facility for Advanced Isotope Research , University of Vienna , A-1090 Vienna , Austria
| | - S Reipert
- Core Facility of Cell Imaging and Ultrastructure Research , University of Vienna , A-1090 Vienna , Austria
| | - P Heffeter
- Institute of Cancer Research , Comprehensive Cancer Center and Research Platform "Translational Cancer Therapy Research" , Medical University of Vienna , A-1090 Vienna , Austria
| | - M A Jakupec
- Institute of Inorganic Chemistry , Research Platform "Translational Cancer Therapy Research," and Research Network "Chemistry meets Microbiology" , University of Vienna , Währinger Straße 42 , A-1090 Vienna , Austria . ; Tel: +43-1-4277-52600
| | - J Mayr
- Institute of Inorganic Chemistry , Research Platform "Translational Cancer Therapy Research," and Research Network "Chemistry meets Microbiology" , University of Vienna , Währinger Straße 42 , A-1090 Vienna , Austria . ; Tel: +43-1-4277-52600
| | - H P Varbanov
- Institute of Inorganic Chemistry , Research Platform "Translational Cancer Therapy Research," and Research Network "Chemistry meets Microbiology" , University of Vienna , Währinger Straße 42 , A-1090 Vienna , Austria . ; Tel: +43-1-4277-52600
| | - C R Kowol
- Institute of Inorganic Chemistry , Research Platform "Translational Cancer Therapy Research," and Research Network "Chemistry meets Microbiology" , University of Vienna , Währinger Straße 42 , A-1090 Vienna , Austria . ; Tel: +43-1-4277-52600
| | - M Galanski
- Institute of Inorganic Chemistry , Research Platform "Translational Cancer Therapy Research," and Research Network "Chemistry meets Microbiology" , University of Vienna , Währinger Straße 42 , A-1090 Vienna , Austria . ; Tel: +43-1-4277-52600
| | - W Berger
- Institute of Cancer Research , Comprehensive Cancer Center and Research Platform "Translational Cancer Therapy Research" , Medical University of Vienna , A-1090 Vienna , Austria
| | - M Wagner
- Department of Microbiology and Ecosystem Science , Research Network "Chemistry meets Microbiology", and Large-Instrument Facility for Advanced Isotope Research , University of Vienna , A-1090 Vienna , Austria
| | - B K Keppler
- Institute of Inorganic Chemistry , Research Platform "Translational Cancer Therapy Research," and Research Network "Chemistry meets Microbiology" , University of Vienna , Währinger Straße 42 , A-1090 Vienna , Austria . ; Tel: +43-1-4277-52600
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19
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Tomonari Y, Kurotaki T, Sato J, Doi T, Kokoshima H, Kanno T, Tsuchitani M, Seely JC. Spontaneous Age-related Lesions of the Kidney Fornices in Sprague-Dawley Rats. Toxicol Pathol 2016; 44:226-32. [PMID: 26957568 DOI: 10.1177/0192623315621193] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The upper portion of the rat kidney pelvis has specialized anatomic structures referred to as fornices. Fornices have a role in urine concentration. Spontaneous lesions including mineralization, epithelial hyperplasia, and inflammatory cell infiltration may occur in the area of the fornices. However, little information regarding specific historical control data or the spontaneous development of these findings in male and female fornices is known. Understanding spontaneous age-related lesions in the area of the fornices versus other portions of the kidney pelvis may be relevant in the identification of test article-induced changes. A retrospective study was conducted of male and female Sprague-Dawley rat kidney fornices over several time points to determine the incidence and severity of mineralization, epithelial hyperplasia, and inflammatory cell infiltration. Based on this investigation, these lesions appeared to increase over time and, in general, occurred earlier and with a greater incidence in females. Regarding those chemicals that may result in lesions of the kidney pelvis, it may be important for pathologists to separately diagnose lesions of the fornices from other portions of the kidney pelvis to help differentiate between any spontaneous age-related and induced changes.
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Affiliation(s)
| | | | - Junko Sato
- LSI Medience Corporation, Kamisu, Ibaraki, Japan
| | - Takuya Doi
- LSI Medience Corporation, Kamisu, Ibaraki, Japan
| | | | | | | | - John Curtis Seely
- Experimental Pathology Laboratories, Inc., Research Triangle Park, North Carolina, USA
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20
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Hart DV, Winter MD, Conway J, Berry CR. Ultrasound appearance of the outer medulla in dogs without renal dysfunction. Vet Radiol Ultrasound 2013; 54:652-8. [PMID: 23738847 DOI: 10.1111/vru.12069] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 05/04/2013] [Indexed: 11/28/2022] Open
Abstract
Ultrasound findings of the canine kidney include a hyperechoic cortex and a hypo to anechoic medulla. In this study, the sonographic appearance of the outer renal medulla in dogs without evidence of renal disease is described. Dogs that underwent abdominal ultrasound over a 6-month period were subjected to review and then divided into six groups based on body weight (kg): < 4.9, 5.0-9.9, 10-19.9, 20-29.9, 30-39.9, and ≥ 40. Chi-square analysis was used to determine if the frequency of a hyperechoic outer medulla was significantly different between weight groups, sex, and age (P-value < 0.05). Of the 145 dogs that met the inclusion criteria, 45 had a hyperechoic outer medulla relative to the cortex and inner medulla. In the remaining dogs, the outer medulla was isoechoic to the cortex. Dogs less than 5 kg had the highest frequency of a hyperechoic outer medulla (P < 0.0001) and dogs greater than 40 kg did not have a hyperechoic outer medulla (P < 0.0001). Sex had no influence on the presence or absence of the hyperechoic outer medulla; however, younger dogs were overrepresented (6.4 ± 0.6 years compared with 7.8 ± 0.4 years; P = 0.04). Ultrasound descriptions of the canine kidney have not taken into account the contributions of the renal cortex and outer medulla. Based on this study of dogs with no clinically significant renal disease, the outer medulla can be isoechoic or hyperechoic to the cortex and a hyperechoic outer medulla is more commonly seen in small breed dogs.
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Affiliation(s)
- Daniel Vander Hart
- Departments of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610
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21
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Options for histological study of the structure and ultrastructure of human urinary bladder epithelium. Biologia (Bratisl) 2012. [DOI: 10.2478/s11756-012-0090-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Nielsen E, Nørhede P, Boberg J, Krag Isling L, Kroghsbo S, Hadrup N, Bredsdorff L, Mortensen A, Christian Larsen J. Identification of Cumulative Assessment Groups of Pesticides. ACTA ACUST UNITED AC 2012. [DOI: 10.2903/sp.efsa.2012.en-269] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Elsa Nielsen
- National Food Institute, Technical University of Denmark, Mørkhøj Denmark
| | - Pia Nørhede
- National Food Institute, Technical University of Denmark, Mørkhøj Denmark
| | - Julie Boberg
- National Food Institute, Technical University of Denmark, Mørkhøj Denmark
| | - Louise Krag Isling
- National Food Institute, Technical University of Denmark, Mørkhøj Denmark
| | - Stine Kroghsbo
- National Food Institute, Technical University of Denmark, Mørkhøj Denmark
| | - Niels Hadrup
- National Food Institute, Technical University of Denmark, Mørkhøj Denmark
| | - Lea Bredsdorff
- National Food Institute, Technical University of Denmark, Mørkhøj Denmark
| | - Alicja Mortensen
- National Food Institute, Technical University of Denmark, Mørkhøj Denmark
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Iwatsuki H, Meguro R, Asano Y, Odagiri S, Li C, Shoumura K. Chelatable Fe (II) is generated in the rat kidneys exposed to ischemia and reperfusion, and a divalent metal chelator, 2, 2'-dipyridyl, attenuates the acute ischemia/reperfusion-injury of the kidneys: a histochemical study by the perfusion-Perls and -Turnbull methods. ACTA ACUST UNITED AC 2008; 71:101-14. [PMID: 18974602 DOI: 10.1679/aohc.71.101] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The perfusion-Perls and -Turnbull methods supplemented by diaminobenzidine intensification demonstrated the generation and localization of chelatable Fe (II) which can catalyze the generation of cytotoxic hydroxyl radicals (OH.) during the Fenton reaction in rat kidneys exposed to 40 min ischemia or 40 min-ischemia followed by 60 min-reperfusion. The kidneys exposed to 40 min-ischemia showed Fe (II)-deposits largely localized in the deeper half of the cortex, where the deposits densely filled the tubular cell nuclei, with a small amount of them in the cytoplasm of the proximal convoluted tubules (PCT). Intraluminally protruded or exfoliated tubular cell nuclei were also filled with the deposits. The kidneys subjected to 40 min-ischemia/ 60 min-reperfusion showed a more extensive distribution of Fe (II)-deposits, including most depths of the cortex. Furthermore, there were numerous exfoliated, Fe (II)-positive nuclei surrounded by a small amount of cytoplasm in the lumen of the PCT. These cells appeared to undergo apoptotic cell death since the lumen of strongly dilated, down-stream, proximal straight tubules were obstructed with numerous apoptotic cells in the kidneys exposed to 40 min-ischemia and 24 h-reperfusion. Pretreatment with a divalent metal chelator, 2, 2'-dipyridyl, effectively inhibited Fe (II)-staining, decreased the number of exfoliated cells in the kidneys with 40 min-ischemia/ 60 m-reperfusion, and decreased the number of apoptotic cells in the kidneys with 40 min-ischemia/24 h-reperfusion. The generation of highly reactive OH. during the Fe2+-catalyzed Fenton reaction was suggested to play a crucial role in ischemia/reperfusion-induced kidney injury.
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Affiliation(s)
- Hiroyasu Iwatsuki
- Department of Neuroanatomy, Histology and Cell Biology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
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SCAGLIONE F, CATALANO D, BESTONSO R, BROVIDA C, D'ANGELO A, ZANATTA R, CORNAGLIA S, CORNAGLIA E, CAPUCCHIO M. Comparison between light and electron microscopy in canine and feline renal pathology: a preliminary study. J Microsc 2008; 232:387-94. [DOI: 10.1111/j.1365-2818.2008.02133.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Pinheiro PFF, Segatelli TM, Francia CCDA, Martinez M, Padovani CR, Franchi MR, Martinez FE. Morphologic changes in the urethral epithelium in an ethanol-drinking rat strain (UChA and UChB). Micron 2007; 38:734-46. [PMID: 17624793 DOI: 10.1016/j.micron.2007.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2007] [Revised: 05/17/2007] [Accepted: 05/18/2007] [Indexed: 10/23/2022]
Abstract
The extreme use of ethanol causes metabolic and pathologic changes in testes and urogenital system in different animal species. The enzyme alcohol dehydrogenase (ADH) catalyses the conversion of ethanol into carcinogenic metabolite acetaldehyde which is partly excreted into the urine. However, papers relating the chronic ethanol consumption to the urethral morphology are unknown. This work evaluates the toxic effect of the chronic ethanol ingestion on the urethral epithelium of UChA and UChB rats. Conventional techniques of histology, histochemistry, immunohistochemistry and ultrastructural analysis were used. The analysis showed the presence of lipid drops and intercellular spaces in the epithelial cells in the urethra of UChA and UChB rats compared to control rats. Urethral neuroendocrine cell were observed and characterized for presenting vesicles containing electron-dense granules associated with nervous fibers. We conclude that the chronic consumption of ethanol induces the presence lipid drops in the epithelial cells of the urethra of UChA and UChB rats. The NE cells of the urethra of UChA and UChB rats did not show alterations under chronic effect of the ethanol.
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Wisløff H, Flåøyen A, Ottesen N, Hovig T. Narthecium ossifragum (L.) huds. causes kidney damage in goats: morphologic and functional effects. Vet Pathol 2003; 40:317-27. [PMID: 12724574 DOI: 10.1354/vp.40-3-317] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We studied the effects of Narthecium ossifragum on goat kidneys. Twenty-five Norwegian dairy goats, 5 weeks to 4 months of age, were orally dosed with an aqueous extract from N. ossifragum. In experiment 1, we studied microscopic and functional changes in 12 animals that were euthanatized 2, 3, 4, 5, and 6 days after treatment. In experiment 2, we included ultrastructural studies on serial renal biopsies and urine analysis from five extract-treated animals and two controls. In addition, urine samples were collected from four dosed and two control goats. Ultrasonography revealed perirenal and retroperitoneal fluids. Microscopic changes were observed after 6 hours. The findings, most obvious in the inner cortex and the outer medulla, consisted of cytoplasmic vacuolization, interstitial edema, and focal necrosis of tubular epithelial cells. Ultrastructurally, the tubules had loss of microvilli, irregular cytoplasmic vacuolization, mitochondrial swelling with loss of cristae, and irregular but continuous basement membranes even with necrosis. In the glomeruli, there were occasional endothelial damage and shortening and swelling of the foot processes. Peritubular capillaries had breaks in the vessel walls and irregular endothelial cell edema, and the interstitium had marked edema. The functional lesions included elevated serum urea, creatinine, and magnesium concentrations, a slight decrease in serum calcium concentration, elevated urine protein and urine protein-creatinine ratio, and increased activities of urine alkaline phosphatase and gamma glutamyl transferase. Our findings indicate a fast-acting toxic principle inducing damage by both direct toxic and secondary ischemic effects.
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Affiliation(s)
- H Wisløff
- National Veterinary Institute, PO Box 8156 Dep., 0033 Oslo, Norway.
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Balloch KJD, Hartley JA, Millar ID, Kibble JD, Robson L. A hypertonicity-activated nonselective conductance in single proximal tubule cells isolated from mouse kidney. J Membr Biol 2003; 192:191-201. [PMID: 12820664 DOI: 10.1007/s00232-002-1075-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The whole-cell patch-clamp technique was used to examine nonselective conductances in single proximal tubule cells isolated from mouse kidney. Single cells were isolated in either the presence or absence of a cocktail designed to stimulate cAMP. Patches were obtained with Na+ Ringer in the bath and Cs+ Ringer in the pipette. On initially achieving the whole-cell configuration, whole-cell currents were small. In cAMP-stimulated cells, with 5 mM ATP in the pipette solution, whole-cell currents increased with time. The activated current was linear, slightly cation-selective, did not discriminate between Na+ and K+ and was inhibited by 100 microM gadolinium. These properties are consistent with the activation of a nonselective conductance, designated G(NS). Activation of G(NS) was abolished with pipette AMP-PNP, ATP plus alkaline phosphatase or in the absence of ATP. In unstimulated cells G(NS) was activated by pipette ATP together with PKA. These data support the hypothesis that G(NS) is activated by a PKA-mediated phosphorylation event. G(NS) was also activated by a hypertonic shock. However, G(NS) does not appear to be involved in regulatory volume increase (RVI), as RVI was unaffected in the presence of the G(NS) blocker gadolinium. Instead, the ATP sensitivity of G(NS) suggests that it may be regulated by the metabolic state of the renal proximal tubule cell.
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Affiliation(s)
- K J D Balloch
- Department of Biomedical Science, Western Bank, University of Sheffield, Sheffield S10 2TN, UK
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Kai K, Sato N, Watanabe A, Shiraiwa K, Ogawa S, Kobayashi Y. Polycystic Disease of the Kidney and Liver in Crj:CD(SD) Rats. J Toxicol Pathol 2001. [DOI: 10.1293/tox.14.51] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Kiyonori Kai
- Laboratory for Toxicological Research, Institute for Life Science Research, Asahi Chemical Industry Co., Ltd
| | - Norihiro Sato
- Laboratory for Toxicological Research, Institute for Life Science Research, Asahi Chemical Industry Co., Ltd
| | - Atsushi Watanabe
- Laboratory for Toxicological Research, Institute for Life Science Research, Asahi Chemical Industry Co., Ltd
| | - Kazumi Shiraiwa
- Laboratory for Toxicological Research, Institute for Life Science Research, Asahi Chemical Industry Co., Ltd
| | - Shinichi Ogawa
- Laboratory for Toxicological Research, Institute for Life Science Research, Asahi Chemical Industry Co., Ltd
| | - Youshiro Kobayashi
- Laboratory for Toxicological Research, Institute for Life Science Research, Asahi Chemical Industry Co., Ltd
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