scholarly journals Glomerular filtration barrier dysfunction in a self-limiting, RNA virus-induced glomerulopathy resembles findings in idiopathic nephrotic syndromes

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Christian Nusshag ◽  
Alisa Stütz ◽  
Stefan Hägele ◽  
Claudius Speer ◽  
Florian Kälble ◽  
...  
Keyword(s):  
Rna Virus ◽  
Serum Levels ◽  
Therapeutic Approaches ◽  
Barrier Dysfunction ◽  
Urokinase Plasminogen Activator Receptor ◽  
Podocyte Injury ◽  
New Therapeutic Approaches ◽  
Glomerular Proteinuria ◽  
Filtration Barrier ◽  
Foot Process

Abstract Podocyte injury has recently been described as unifying feature in idiopathic nephrotic syndromes (INS). Puumala hantavirus (PUUV) infection represents a unique RNA virus-induced renal disease with significant proteinuria. The underlying pathomechanism is unclear. We hypothesized that PUUV infection results in podocyte injury, similar to findings in INS. We therefore analyzed standard markers of glomerular proteinuria (e.g. immunoglobulin G [IgG]), urinary nephrin excretion (podocyte injury) and serum levels of the soluble urokinase plasminogen activator receptor (suPAR), a proposed pathomechanically involved molecule in INS, in PUUV-infected patients. Hantavirus patients showed significantly increased urinary nephrin, IgG and serum suPAR concentrations compared to healthy controls. Nephrin and IgG levels were significantly higher in patients with severe proteinuria than with mild proteinuria, and nephrin correlated strongly with biomarkers of glomerular proteinuria over time. Congruently, electron microcopy analyses showed a focal podocyte foot process effacement. suPAR correlated significantly with urinary nephrin, IgG and albumin levels, suggesting suPAR as a pathophysiological mediator in podocyte dysfunction. In contrast to INS, proteinuria recovered autonomously in hantavirus patients. This study reveals podocyte injury as main cause of proteinuria in hantavirus patients. A better understanding of the regenerative nature of hantavirus-induced glomerulopathy may generate new therapeutic approaches for INS.

scholarly journals Progress in Pathogenesis of Proteinuria

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Aihua Zhang ◽  
Songming Huang
Keyword(s):  
Endothelial Cells ◽  
Glomerular Filtration ◽  
Transient Receptor Potential ◽  
Receptor Potential ◽  
Renal Diseases ◽  
Barrier Dysfunction ◽  
Glomerular Filtration Barrier ◽  
Glomerular Proteinuria ◽  
Filtration Barrier ◽  
Glomerular Endothelial Cells

Aims. Proteinuria not only is a sign of kidney damage, but also is involved in the progression of renal diseases as an independent pathologic factor. Clinically, glomerular proteinuria is most commonly observed, which relates to structural and functional anomalies in the glomerular filtration barrier. The aim of this paper was to describe the pathogenesis of glomerular proteinuria.Data Sources. Articles on glomerular proteinuria retrieved from Pubmed and MEDLINE in the recent 5 years were reviewed.Results. The new understanding of the roles of glomerular endothelial cells and the glomerular basement membrane (GBM) in the pathogenesis of glomerular proteinuria was gained. The close relationships of slit diaphragm (SD) molecules such as nephrin, podocin, CD2-associated protein (CD2AP), a-actinin-4, transient receptor potential cation channel 6 (TRPC6), Densin and membrane-associated guanylate kinase inverted 1 (MAGI-1),α3β1 integrin, WT1, phospholipase C epsilon-1 (PLCE1), Lmx1b, and MYH9, and mitochondrial disorders and circulating factors in the pathogenesis of glomerular proteinuria were also gradually discovered.Conclusion. Renal proteinuria is a manifestation of glomerular filtration barrier dysfunction. Not only glomerular endothelial cells and GBM, but also the glomerular podocytes and their SDs play an important role in the pathogenesis of glomerular proteinuria.

scholarly journals Dosage-dependent role of Rac1 in podocyte injury

2016 ◽  
Vol 310 (8) ◽  
pp. F777-F784 ◽  
Author(s):  
Xiaoyang Wan ◽  
Mi-Sun Lee ◽  
Weibin Zhou
Keyword(s):  
Kidney Injury ◽  
Small Gtpase ◽  
Glomerular Sclerosis ◽  
Transgenic Zebrafish ◽  
Dependent Manner ◽  
Podocyte Injury ◽  
Filtration Barrier ◽  
Foot Process Effacement ◽  
Rac1 Activity ◽  
Foot Process

Activation of small GTPase Rac1 in podocytes is associated with rodent models of kidney injury and familial nephrotic syndrome. Induced Rac1 activation in podocytes in transgenic mice results in rapid transient proteinuria and foot process effacement, but not glomerular sclerosis. Thus it remains an open question whether abnormal activation of Rac1 in podocytes is sufficient to cause permanent podocyte damage. Using a number of transgenic zebrafish models, we showed that moderate elevation of Rac1 activity in podocytes did not impair the glomerular filtration barrier but aggravated metronidazole-induced podocyte injury, while inhibition of Rac1 activity ameliorated metronidazole-induced podocyte injury. Furthermore, a further increase in Rac1 activity in podocytes was sufficient to cause proteinuria and foot process effacement, which resulted in edema and lethality in juvenile zebrafish. We also found that activation of Rac1 in podocytes significantly downregulated the expression of nephrin and podocin, suggesting an adverse effect of Rac1 on slit diaphragm protein expression. Taken together, our data have demonstrated a causal link between excessive Rac1 activity and podocyte injury in a dosage-dependent manner, and transgenic zebrafish of variable Rac1 activities in podocytes may serve as useful animal models for the study of Rac1-related podocytopathy.

scholarly journals Shp2 Associates with and Enhances Nephrin Tyrosine Phosphorylation and Is Necessary for Foot Process Spreading in Mouse Models of Podocyte Injury

2015 ◽  
Vol 36 (4) ◽  
pp. 596-614 ◽  
Author(s):  
Rakesh Verma ◽  
Madhusudan Venkatareddy ◽  
Anne Kalinowski ◽  
Sanjeevkumar R. Patel ◽  
David J. Salant ◽  
...  
Keyword(s):  
Cell Culture ◽  
Tyrosine Phosphorylation ◽  
Sh2 Domain ◽  
Slit Diaphragm ◽  
Dependent Manner ◽  
Glomerular Diseases ◽  
Podocyte Injury ◽  
Filtration Barrier ◽  
Signaling Events ◽  
Foot Process

In most forms of glomerular diseases, loss of size selectivity by the kidney filtration barrier is associated with changes in the morphology of podocytes. The kidney filtration barrier is comprised of the endothelial lining, the glomerular basement membrane, and the podocyte intercellular junction, or slit diaphragm. The cell adhesion proteins nephrin and neph1 localize to the slit diaphragm and transduce signals in a Src family kinase Fyn-mediated tyrosine phosphorylation-dependent manner. Studies in cell culture suggest nephrin phosphorylation-dependent signaling events are primarily involved in regulation of actin dynamics and lamellipodium formation. Nephrin phosphorylation is a proximal event that occurs both during development and following podocyte injury. We hypothesized that abrogation of nephrin phosphorylation following injury would prevent nephrin-dependent actin remodeling and foot process morphological changes. Utilizing a biased screening approach, we found nonreceptor Src homology 2 (sh2) domain-containing phosphatase Shp2 to be associated with phosphorylated nephrin. We observed an increase in nephrin tyrosine phosphorylation in the presence of Shp2 in cell culture studies. In the human glomerulopathies minimal-change nephrosis and membranous nephropathy, there is an increase in Shp2 phosphorylation, a marker of increased Shp2 activity. Mouse podocytes lacking Shp2 do not develop foot process spreading when subjected to podocyte injuryin vivousing protamine sulfate or nephrotoxic serum (NTS). In the NTS model, we observed a lack of foot process spreading in mouse podocytes with Shp2 deleted and smaller amounts of proteinuria. Taken together, these results suggest that Shp2-dependent signaling events are necessary for changes in foot process structure and function following injury.

New therapeutic approaches for polymyositis and dermatomyositis

2011 ◽  
Vol 152 (39) ◽  
pp. 1552-1559 ◽  
Author(s):  
Katalin Dankó ◽  
Melinda Vincze
Keyword(s):  
Immunosuppressive Agents ◽  
Inflammatory Myopathy ◽  
Proximal Muscle ◽  
Therapeutic Approaches ◽  
First Line ◽  
New Therapeutic Approaches ◽  
Remission Period ◽  
Immune Mediated ◽  
Systemic Manifestations ◽  
Line Of Therapy

Inflammatory myopathies are chronic, immune-mediated diseases characterized with progressive proximal muscle weakness. They encompass a variety of syndromes with protean manifestations. The aims of therapy are to increase muscle strength, prevent the development of contractures, and to manage the systemic manifestations of the disease. This is a complex treatment which requires routine and wide knowledge. The most important task is to recognize the disease and guide the patient to immunologic center. Although the first line of therapy continues to include corticosteroids, there are a multitude of agents available for treating patients with myositis. There are several different immunosuppressive agents which may be applied alone or in combination with each other, as well as an increasing number of novel and exciting biologic agents targeting molecules participating in the pathogenesis of inflammatory myopathy. Physiotherapy and rehabilitation in the remission period may significantly improve the functional outcome of patients with these disorders. Orv. Hetil., 2011, 152, 1552–1559.

scholarly journals New Aspects of the Epigenetics of Pancreatic Carcinogenesis

Epigenomes ◽  
2020 ◽  
Vol 4 (3) ◽  
pp. 18
Author(s):  
Murat Toruner ◽  
Martin E. Fernandez-Zapico ◽  
Christopher L. Pin
Keyword(s):  
Pancreatic Cancer ◽  
Dna Methylation ◽  
Survival Rate ◽  
Epigenetic Mechanisms ◽  
Therapeutic Approaches ◽  
Cancer Epigenetics ◽  
Pancreatic Carcinogenesis ◽  
New Therapeutic Approaches ◽  
Environmental Events ◽  
Underlying Pathogenesis

Pancreatic cancer remains among the deadliest forms of cancer with a 5 year survival rate less than 10%. With increasing numbers being observed, there is an urgent need to elucidate the pathogenesis of pancreatic cancer. While both contribute to disease progression, neither genetic nor environmental factors completely explain susceptibility or pathogenesis. Defining the links between genetic and environmental events represents an opportunity to understand the pathogenesis of pancreatic cancer. Epigenetics, the study of mitotically heritable changes in genome function without a change in nucleotide sequence, is an emerging field of research in pancreatic cancer. The main epigenetic mechanisms include DNA methylation, histone modifications and RNA interference, all of which are altered by changes to the environment. Epigenetic mechanisms are being investigated to clarify the underlying pathogenesis of pancreatic cancer including an increasing number of studies examining the role as possible diagnostic and prognostic biomarkers. These mechanisms also provide targets for promising new therapeutic approaches for this devastating malignancy.

scholarly journals A Brief Analysis of Tissue-Resident NK Cells in Pregnancy and Endometrial Diseases: The Importance of Pharmacologic Modulation

Immuno ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 174-193
Author(s):  
Jenny Valentina Garmendia ◽  
Juan Bautista De Sanctis
Keyword(s):  
Nk Cells ◽  
Nk Cell ◽  
Embryo Implantation ◽  
Inflammatory Cells ◽  
Cell Physiology ◽  
Therapeutic Approaches ◽  
Pharmacological Modulation ◽  
New Therapeutic Approaches ◽  
Pharmacologic Modulation ◽  
Inflammatory Burden

NK cells are lymphocytes involved in the innate and adaptative immune response. These cells are located in peripheral blood and tissues with ample functions, from immune vigilant to tolerogenic reactions. In the endometrium, NK cell populations vary depending on age, hormones, and inflammation. When pregnancy occurs, tissue-resident NK cells and conventional NK cells are recruited to protect the fetus, a tolerogenic response. On the contrary, in the inflamed endometrium, various inflammatory cells down-regulate NK tolerance and impair embryo implantation. Therefore, NK cells’ pharmacological modulation is difficult to achieve. Several strategies have been used, from progesterone, lipid emulsions to steroids; the success has not been as expected. However, new therapeutic approaches have been proposed to decrease the endometrial inflammatory burden and increase pregnancy success based on understanding NK cell physiology.

scholarly journals Thrombomodulin is upregulated in the kidneys of women with pre-eclampsia

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Cleo C. L. van Aanhold ◽  
Manon Bos ◽  
Katrina M. Mirabito Colafella ◽  
Marie-Louise P. van der Hoorn ◽  
Ron Wolterbeek ◽  
...  
Keyword(s):  
Glomerular Filtration ◽  
Early Stage ◽  
Vascular Inflammation ◽  
Angiogenesis Inhibitor ◽  
Serum Levels ◽  
Dependent Manner ◽  
Glomerular Filtration Barrier ◽  
Soluble Thrombomodulin ◽  
Filtration Barrier ◽  
Glomerular Endothelium

AbstractThe endothelial glycoprotein thrombomodulin regulates coagulation, vascular inflammation and apoptosis. In the kidney, thrombomodulin protects the glomerular filtration barrier by eliciting crosstalk between the glomerular endothelium and podocytes. Several glomerular pathologies are characterized by a loss of glomerular thrombomodulin. In women with pre-eclampsia, serum levels of soluble thrombomodulin are increased, possibly reflecting a loss from the glomerular endothelium. We set out to investigate whether thrombomodulin expression is decreased in the kidneys of women with pre-eclampsia and rats exposed to an angiogenesis inhibitor. Thrombomodulin expression was examined using immunohistochemistry and qPCR in renal autopsy tissues collected from 11 pre-eclamptic women, 22 pregnant controls and 11 hypertensive non-pregnant women. Further, kidneys from rats treated with increasing doses of sunitinib or sunitinib in combination with endothelin receptor antagonists were studied. Glomerular thrombomodulin protein levels were increased in the kidneys of women with pre-eclampsia. In parallel, in rats exposed to sunitinib, glomerular thrombomodulin was upregulated in a dose-dependent manner, and the upregulation of glomerular thrombomodulin preceded the onset of histopathological changes. Selective ETAR blockade, but not dual ETA/BR blockade, normalised the sunitinib-induced increase in thrombomodulin expression and albuminuria. We propose that glomerular thrombomodulin expression increases at an early stage of renal damage induced by antiangiogenic conditions. The upregulation of this nephroprotective protein in glomerular endothelial cells might serve as a mechanism to protect the glomerular filtration barrier in pre-eclampsia.

scholarly journals The Effect of a Polyester Nanofibrous Membrane with a Fibrin-Platelet Lysate Coating on Keratinocytes and Endothelial Cells in a Co-Culture System

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 457
Author(s):  
Andreu Blanquer ◽  
Jana Musilkova ◽  
Elena Filova ◽  
Johanka Taborska ◽  
Eduard Brynda ◽  
...  
Keyword(s):  
Wound Healing ◽  
Endothelial Cells ◽  
Chronic Wounds ◽  
Human Keratinocytes ◽  
Skin Wound ◽  
Platelet Lysate ◽  
Therapeutic Approaches ◽  
Skin Wound Healing ◽  
New Therapeutic Approaches ◽  
Proliferation And Differentiation

Chronic wounds affect millions of patients worldwide, and it is estimated that this number will increase steadily in the future due to population ageing. The research of new therapeutic approaches to wound healing includes the development of nanofibrous meshes and the use of platelet lysate (PL) to stimulate skin regeneration. This study considers a combination of a degradable electrospun nanofibrous blend of poly(L-lactide-co-ε-caprolactone) and poly(ε-caprolactone) (PLCL/PCL) membranes (NF) and fibrin loaded with various concentrations of PL aimed at the development of bioactive skin wound healing dressings. The cytocompatibility of the NF membranes, as well as the effect of PL, was evaluated in both monocultures and co-cultures of human keratinocytes and human endothelial cells. We determined that the keratinocytes were able to adhere on all the membranes, and their increased proliferation and differentiation was observed on the membranes that contained fibrin with at least 50% of PL (Fbg + PL) after 14 days. With respect to the co-culture experiments, the membranes with fibrin with 20% of PL were observed to enhance the metabolic activity of endothelial cells and their migration, and the proliferation and differentiation of keratinocytes. The results suggest that the newly developed NF combined with fibrin and PL, described in the study, provides a promising dressing for chronic wound healing purposes.

scholarly journals Regulation of Eosinophilia in Asthma—New Therapeutic Approaches for Asthma Treatment

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 817
Author(s):  
Ruth P. Cusack ◽  
Christiane E. Whetstone ◽  
Yanqing Xie ◽  
Maral Ranjbar ◽  
Gail M. Gauvreau
Keyword(s):  
Drug Targets ◽  
Airflow Obstruction ◽  
Chronic Inflammatory Disease ◽  
Therapeutic Approaches ◽  
Eosinophilic Asthma ◽  
Airway Eosinophilia ◽  
Gm Csf ◽  
New Therapeutic Approaches ◽  
Cellular Apoptosis ◽  
Reversible Airflow Obstruction

Asthma is a complex and chronic inflammatory disease of the airways, characterized by variable and recurring symptoms, reversible airflow obstruction, bronchospasm, and airway eosinophilia. As the pathophysiology of asthma is becoming clearer, the identification of new valuable drug targets is emerging. IL-5 is one of these such targets because it is the major cytokine supporting eosinophilia and is responsible for terminal differentiation of human eosinophils, regulating eosinophil proliferation, differentiation, maturation, migration, and prevention of cellular apoptosis. Blockade of the IL-5 pathway has been shown to be efficacious for the treatment of eosinophilic asthma. However, several other inflammatory pathways have been shown to support eosinophilia, including IL-13, the alarmin cytokines TSLP and IL-33, and the IL-3/5/GM-CSF axis. These and other alternate pathways leading to airway eosinophilia will be described, and the efficacy of therapeutics that have been developed to block these pathways will be evaluated.

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