scholarly journals Pathophysiology of the Peritoneal Membrane during Peritoneal Dialysis: The Role of Hyaluronan

2011 ◽  
Vol 2011 ◽  
pp. 1-11 ◽  
Author(s):  
Susan Yung ◽  
Tak Mao Chan
Keyword(s):  
Peritoneal Dialysis ◽  
Cell Function ◽  
Mesothelial Cell ◽  
Protective Role ◽  
Mesothelial Cells ◽  
Cell Phenotype ◽  
Peritoneal Membrane ◽  
Structural Support

During peritoneal dialysis (PD), constant exposure of mesothelial cells to bioincompatible PD solutions results in the denudation of the mesothelial monolayer and impairment of mesothelial cell function. Hyaluronan, a major component of extracellular matrices, is synthesized by mesothelial cells and contributes to remesothelialization, maintenance of cell phenotype, and tissue remodeling and provides structural support to the peritoneal membrane. Chronic peritoneal inflammation is observed in long-term PD patients and is associated with increased hyaluronan synthesis. During inflammation, depolymerization of hyaluronan may occur with the generation of hyaluronan fragments. In contrast to native hyaluronan which offers a protective role to the peritoneum, hyaluronan fragments exacerbate inflammatory and fibrotic processes and therefore assist in the destruction of the tissue. This paper will discuss the contribution of mesothelial cells to peritoneal membrane alterations that are induced by PD and the putative role of hyaluronan in these processes.

Overnight Mesothelial Cell Exfoliation: A Magic Tool for Predicting Future Ultrafiltration Failure in Patients on Continuous Ambulatory Peritoneal Dialysis

2008 ◽  
Vol 28 (3_suppl) ◽  
pp. 107-113
Author(s):  
Talerngsak Kanjanabuch ◽  
Monchai Siribamrungwong ◽  
Rungrote Khunprakant ◽  
Sirigul Kanjanabuch ◽  
Piyathida Jeungsmarn ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Continuous Ambulatory Peritoneal Dialysis ◽  
Mesothelial Cell ◽  
Mesothelial Cells ◽  
Nutrition Status ◽  
Continuous Exposure ◽  
Peritoneal Membrane ◽  
Dialysis Solution ◽  
Ultrafiltration Failure

⋄ Background Continuous exposure of the peritoneal membrane to dialysis solutions during long-term dialysis results in mesothelial cell loss, peritoneal membrane damage, and thereby, ultrafiltration (UF) failure, a major determinant of mortality in patients on continuous ambulatory peritoneal dialysis (CAPD). Unfortunately, none of tests available today can predict long-term UF decline. Here, we propose a new tool to predict such a change. ⋄ Mesothelial cells from 8-hour overnight effluents (1.36% glucose dialysis solution) were harvested, co-stained with cytokeratin (a mesothelial marker) and TUNEL (an apoptotic marker), and were counted using flow cytometry in 48 patients recently started on CAPD. Adequacy of dialysis, UF, nutrition status, dialysate cancer antigen 125 (CA125), and a peritoneal equilibration test (3.86% glucose peritoneal dialysis solution) were simultaneously assessed and were reevaluated 1 year later. ⋄ Results The numbers of total and apoptotic mesothelial cells were 0.19 ± 0.19 million and 0.08 ± 0.12 million cells per bag, respectively. Both numbers correlated well with the levels of end dialysate–to–initial dialysate (D/D0) glucose, dialysate-to-plasma (D/P) creatinine, and sodium dipping. Notably, the counts of cells of both types in patients with diabetes or with high or high-average transport were significantly greater than the equivalent counts in nondiabetic patients or those with low or low-average transport. A cutoff of 0.06 million total mesothelial cells per bag had sensitivity of 1 and a specificity of 0.75 in predicting a further decline in D/D0 glucose and a sensitivity of 0.86 and a specificity of 0.63 to predict a further decline in UF over a 1-year period. In contrast, dialysate CA125 and other measured parameters had low predictive values. ⋄ Conclusions The greater the loss of exfoliated cells, the worse the expected decline in UF. The ability of a count of mesothelial cells to predict a future decline in UF warrants further investigation in clinical practice.

Continuous Mesothelial Injury and Regeneration during long Term Peritoneal Dialysis

1987 ◽  
Vol 7 (3) ◽  
pp. 148-156 ◽  
Author(s):  
Lazaro Gotloib ◽  
Abshalom Shostack ◽  
Phina Bar-Sella ◽  
Ricardo Cohen
Keyword(s):  
Peritoneal Dialysis ◽  
Connective Tissue ◽  
Peritoneal Fluid ◽  
Mesothelial Cell ◽  
Mesothelial Cells

This study reconstructs the whole sequence of mesothelial injury and regeneration in patients on longterm peritoneal dialysis. Our observations indicate that peritoneal dialysis induces a process of continuous mesothelial injury and regeneration. New mesothelial cells seem to originate from wandering mesothelial cells of the peritoneal fluid, as well as from mesothelial cell precursors localized in the sub-mesothelial connective tissue.

Biocompatibility of Peritoneal Dialysis Fluids: Long-term Exposure of Nonuremic Rats

2004 ◽  
Vol 24 (1) ◽  
pp. 37-47 ◽  
Author(s):  
Barbara Musi ◽  
Magnus Braide ◽  
Ola Carlsson ◽  
Anders Wieslander ◽  
Ann Albrektsson ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Growth Factor ◽  
Solute Transport ◽  
Transforming Growth Factor ◽  
Cell Damage ◽  
Mesothelial Cell ◽  
Mesothelial Cells ◽  
Vascular Density ◽  
Tissue Thickness

Objectives Long-term peritoneal dialysis (PD) leads to structural and functional changes in the peritoneum. The aim of the present study was to investigate the long-term effects of PD fluid components, glucose and glucose degradation products (GDP), and lactate-buffered solution on morphology and transport characteristics in a nonuremic rat model. Methods Rats were subjected to two daily intraperitoneal injections (20 mL/day) during 12 weeks of one of the following: commercial PD fluid (Gambrosol, 4%; Gambro AB, Lund, Sweden), commercial PD fluid with low GDP levels (Gambrosol trio, 4%; Gambro AB), sterile-filtered PD fluid (4%) without GDP, or a glucose-free lactate-buffered PD fluid. Punctured and untreated controls were used. Following exposure, the rats underwent a single 4-hour PD dwell (30 mL, 4% glucose) to determine peritoneal function. Additionally, submesothelial tissue thickness, percentage of high mesothelial cells (perpendicular diameter > 2 μm), vascular density, vascular endothelial growth factor (VEGF), and transforming growth factor (TGF) β1 mRNA expression were determined. Submesothelial collagen concentration was estimated by van Gieson staining. Results Submesothelial tissue thickness and vascular density, mediated by VEGF and TGFβ production, in the diaphragmatic peritoneum increased significantly in rats exposed to any PD fluid. Gambrosol induced a marked increased fibrosis of the hepatic peritoneum. A significant increase in high mesothelial cells was observed in the Gambrosol group only. Net ultrafiltration was reduced in the Gambrosol and in the glucose-free groups compared to untreated controls. Small solute transport was unchanged, but all groups exposed to fluids showed significantly increased lymph flow. Conclusions Our results show that long-term exposure to different components of PD fluids leads to mesothelial cell damage, submesothelial fibrosis, and neoangiogenesis. Mesothelial cell damage could be connected to the presence of GDP; the other changes were similar for all fluids. Peritoneal transport characteristics did not change in any consistent way and the neoangiogenesis observed was not paralleled by increased solute transport.

scholarly journals Transition of Mesothelial Cell to Fibroblast in Peritoneal Dialysis: EMT, Stem Cell or Bystander?

2015 ◽  
Vol 35 (1) ◽  
pp. 14-25 ◽  
Author(s):  
Yu Liu ◽  
Zheng Dong ◽  
Hong Liu ◽  
Jiefu Zhu ◽  
Fuyou Liu ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Epithelial Mesenchymal Transition ◽  
Experimental Studies ◽  
Mesothelial Cell ◽  
Local Environment ◽  
Lineage Tracing ◽  
Peritoneal Fibrosis ◽  
Mesenchymal Transition

Long-term peritoneal dialysis (PD) can lead to fibrotic changes in the peritoneum, characterized by loss of mesothelial cells (MCs) and thickening of the submesothelial area with an accumulation of collagen and myofibroblasts. The origin of myofibroblasts is a central question in peritoneal fibrosis that remains unanswered at present. Numerous clinical and experimental studies have suggested that MCs, through epithelial-mesenchymal transition (EMT), contribute to the pool of peritoneal myofibroblasts. However, recent work has placed significant doubts on the paradigm of EMT in organ fibrogenesis (in the kidney particularly), highlighting the need to reconsider the role of EMT in the generation of myofibroblasts in peritoneal fibrosis. In particular, selective cell isolation and lineage-tracing experiments have suggested the existence of progenitor cells in the peritoneum, which are able to switch to fibroblast-like cells when stimulated by the local environment. These findings highlight the plastic nature of MCs and its contribution to peritoneal fibrogenesis. In this review, we summarize the key findings and caveats of EMT in organ fibrogenesis, with a focus on PD-related peritoneal fibrosis, and discuss the potential of peritoneal MCs as a source of myofibroblasts.

scholarly journals Unfavorable Effects of Peritoneal Dialysis Solutions on the Peritoneal Membrane: The Role of Oxidative Stress

Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 768
Author(s):  
Stefanos Roumeliotis ◽  
Evangelia Dounousi ◽  
Marios Salmas ◽  
Theodoros Eleftheriadis ◽  
Vassilios Liakopoulos
Keyword(s):  
Oxidative Stress ◽  
Peritoneal Dialysis ◽  
Peritoneal Membrane ◽  
Peritoneal Fibrosis ◽  
Structural Alterations ◽  
And Function ◽  
Dialysis Solutions ◽  
Harmful Effects

One of the main limitations to successful long-term use of peritoneal dialysis (PD) as a renal replacement therapy is the harmful effects of PD solutions to the structure and function of the peritoneal membrane (PM). In PD, the PM serves as a semipermeable membrane that, due to exposure to PD solutions, undergoes structural alterations, including peritoneal fibrosis, vasculopathy, and neoangiogenesis. In recent decades, oxidative stress (OS) has emerged as a novel risk factor for mortality and cardiovascular disease in PD patients. Moreover, it has become evident that OS plays a pivotal role in the pathogenesis and development of the chronic, progressive injury of the PM. In this review, we aimed to present several aspects of OS in PD patients, including the pathophysiologic effects on the PM, clinical implications, and possible therapeutic antioxidant strategies that might protect the integrity of PM during PD therapy.

Long-Term Chronic Toxicity and Mesothelial Cell Reactions Induced by Potassium Octatitanate Fibers (TISMO) in the Left Thoracic Cavity in A/J Female Mice

2015 ◽  
Vol 34 (4) ◽  
pp. 325-335 ◽  
Author(s):  
Masanao Yokohira ◽  
Nozomi Hashimoto ◽  
Toshitaka Nakagawa ◽  
Yuko Nakano ◽  
Keiko Yamakawa ◽  
...  
Keyword(s):  
Mesothelial Cell ◽  
Mesothelial Cells ◽  
Mouse Lung ◽  
Thoracic Cavity ◽  
Direct Effects ◽  
Pleural Mesothelial Cells ◽  
Chronic Effects ◽  
Trade Name ◽  
Potassium Octatitanate Fibers

The present study was conducted to examine the chronic effects of potassium octatitanate fibers (trade name TISMO; chemical formula K2O·6TiO2) on the mouse lung and thoracic cavity. This method of infusion was employed to examine the direct effects of the fibers to the pleura. In the present study, 52- and 65-week experiments were employed to examine the long-term chronic effects after infusion of fiber-shaped TISMO into the thoracic cavities of A/J mice. Following this infusion, TISMO fibers were observed in the alveoli, indicating penetration through the visceral pleura. The additional histopathological detection of TISMO fibers in the liver, spleen, kidneys, ovary, heart, bone marrow, and brain of TISMO-infused mice indicated migration of the fibers out from the thoracic cavity. Atypical mesothelial cells with severe pleural proliferation were observed, but malignant mesotheliomas were not detected. This study demonstrated that intrathoracic infusion of TISMO fiber did not cause malignant mesothelioma but did cause severe chronic inflammation and proliferation of pleural mesothelial cells.

Mesothelial Cells

2007 ◽  
Vol 27 (2_suppl) ◽  
pp. 110-115 ◽  
Author(s):  
Susan Yung ◽  
Chan Tak Mao
Keyword(s):  
Mesothelial Cell ◽  
In Vitro Models ◽  
Mesothelial Cells ◽  
Dynamic Membrane ◽  
Peritoneal Mesothelial Cells ◽  
Immunohistochemical Markers ◽  
Vitro Model ◽  
And Function

♦ Background The introduction of peritoneal dialysis (PD) as a modality of renal replacement therapy has provoked much interest in the biology of the peritoneal mesothelial cell. Mesothelial cells isolated from omental tissue have immunohistochemical markers that are identical to those of mesothelial stem cells, and omental mesothelial cells can be cultivated in vitro to study changes to their biologic functions in the setting of PD. ♦ Method The present article describes the structure and function of mesothelial cells in the normal peritoneum and details the morphologic changes that occur after the introduction of PD. Furthermore, this article reviews the literature of mesothelial cell culture and the limitations of in vitro studies. ♦ Results The mesothelium is now considered to be a dynamic membrane that plays a pivotal role in the homeostasis of the peritoneal cavity, contributing to the control of fluid and solute transport, inflammation, and wound healing. These functional properties of the mesothelium are compromised in the setting of PD. Cultures of peritoneal mesothelial cells from omental tissue provide a relevant in vitro model that allows researchers to assess specific molecular pathways of disease in a distinct population of cells. Structural and functional attributes of mesothelial cells are discussed in relation to long-term culture, proliferation potential, age of tissue donor, use of human or animal in vitro models, and how the foregoing factors may influence in vitro data. ♦ Conclusions The ability to propagate mesothelial cells in culture has resulted, over the past two decades, in an explosion of mesothelial cell research pertaining to PD and peritoneal disorders. Independent researchers have highlighted the potential use of mesothelial cells as targets for gene therapy or transplantation in the search to provide therapeutic strategies for the preservation of the mesothelium during chemical or bacterial injury.

Keratoprostheses in silicone oil-filled eyes: long-term outcomes

2018 ◽  
Vol 103 (6) ◽  
pp. 781-788 ◽  
Author(s):  
Geetha Iyer ◽  
Bhaskar Srinivasan ◽  
Shweta Agarwal ◽  
Ruchika Pattanaik ◽  
Ekta Rishi ◽  
...  
Keyword(s):  
Silicone Oil ◽  
Vitreoretinal Surgery ◽  
Retrospective Chart Review ◽  
Protective Role ◽  
Visual Rehabilitation ◽  
Two Factors

PurposeTo analyse the functional and anatomical outcomes of different types of keratoprostheses in eyes with retained silicone oil following vitreoretinal surgery.MethodsRetrospective chart review of patients operated with any type of permanent keratoprosthesis (Kpro) in silicone oil-filled eyes between March 2003 and June 2017 were analysed.Results40 silicone oil-filled eyes underwent keratoprostheses, of which 22 were type 1 and 18 were type 2 Kpros (Lucia variant—nine, modified osteo odonto kerato prosthesis (MOOKP)—four, Boston type 2—three and osteoKpro—two) with a mean follow-up of 61.54 , 42.77, 45.25 , 25 and 37 months, respectively. Anatomic retention of the primary Kpro was noted in 33 eyes (82.5%). A best-corrected visual acuity of better than 20/200 and 20/400 was achieved in 26 (65%)+32 (80%) eyes. Retroprosthetic membrane (RPM) was the most common complication noted in 17 eyes (42.5%). Perioptic graft melt was noted in 4 of 22 eyes of the type 1 Kpro (2 (10.5%) without associated ocular surface disorder (OSD)) and in 1 eye each of Boston and Lucia type 2 Kpro. Laminar resorption occurred in one eye each of the MOOKP and OKP groups. Endophthalmitis and glaucoma did not occur in any eye.ConclusionAppropriately chosen keratoprosthesis is a viable option for visual rehabilitation in eyes post vitreoretinal surgery with retained silicone oil-induced keratopathy not amenable to conventional penetrating keratoplasty. Kpro melt among type 1 Kpro did not occur in 89.5% eyes without associated OSD (19 of 22 eyes), despite the lack of aqueous humour and presence of RPM (4 eyes), two factors considered to play a significant role in the causation of sterile melts. Of interest to note was the absence of infection in any of these eyes. The possible protective role of oil from endophthalmitis is interesting, though yet to be ascertained.

scholarly journals Glutathione Protects Lactobacillus sanfranciscensis against Freeze-Thawing, Freeze-Drying, and Cold Treatment

2010 ◽  
Vol 76 (9) ◽  
pp. 2989-2996 ◽  
Author(s):  
Juan Zhang ◽  
Guo-Cheng Du ◽  
Yanping Zhang ◽  
Xian-Yan Liao ◽  
Miao Wang ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Stress Responses ◽  
Freeze Drying ◽  
Unsaturated Fatty Acids ◽  
Cold Treatment ◽  
Protective Role ◽  
Intracellular Accumulation ◽  
Lactobacillus Sanfranciscensis

ABSTRACT Lactobacillus sanfranciscensis DSM20451 cells containing glutathione (GSH) displayed significantly higher resistance against cold stress induced by freeze-drying, freeze-thawing, and 4°C cold treatment than those without GSH. Cells containing GSH were capable of maintaining their membrane structure intact when exposed to freeze-thawing. In addition, cells containing GSH showed a higher proportion of unsaturated fatty acids in cell membranes upon long-term cold treatment. Subsequent studies revealed that the protective role of GSH against cryodamage of the cell membrane is partly due to preventing peroxidation of membrane fatty acids and protecting Na+,K+-ATPase. Intracellular accumulation of GSH enhanced the survival and the biotechnological performance of L. sanfranciscensis, suggesting that the robustness of starters for sourdough fermentation can be improved by selecting GSH-accumulating strains. Moreover, the results of this study may represent a further example of mechanisms for stress responses in lactic acid bacteria.

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