scholarly journals Renal tubule Na,K-ATPase polarity in glucocorticoid-induced polycystic kidney disease.

1993 ◽  
Vol 41 (4) ◽  
pp. 555-558 ◽  
Author(s):  
M R Ogborn ◽  
S Sareen ◽  
P C Grimm

Cyst formation in polycystic kidney disease (PKD) involves proliferation of cyst lining epithelial and changes in trans-epithelial fluid and electrolyte transport. In vitro studies have suggested that mislocation of Na,K-ATPase to the apical tubular surface may be an important component of cyst fluid transport. We undertook in vivo studies of Na,K-ATPase location using the "threshold" murine model of glucocorticoid-induced PKD (GIPKD). Using histological, immunohistochemical, and densitometric techniques, we compared cyst formation and the cellular location of Na,K-ATPase in suckling C3H (low threshold for GIPKD) and DBA (high threshold) mice given an inducing dose of 200 mg/kg methylprednisolone acetate. As expected, C3H mice demonstrated greater cyst formation as measured by proportion of section area occupied by the tubule lumen (26.7% vs 15.5%; p < 0.001). Cyst formation was associated with increased Na,K-ATPase staining and increased apical Na,K-ATPase location. MPA treatment in C3H mice resulted in apical staining that exceeded basolateral staining (35.3% of reference window vs 29.8%; p < 0.001). The relatively GIPKD-resistant DBA mice did not show such change in Na,K-ATPase location. These immunohistochemical studies suggest a role for Na,K-ATPase in renal cyst formation.

2020 ◽  
Author(s):  
Shirin V. Sundar ◽  
Xia Zhou ◽  
Brenda S. Magenheimer ◽  
Gail A. Reif ◽  
Darren P. Wallace ◽  
...  

ABSTRACTAutosomal dominant polycystic kidney disease (ADPKD) is a debilitating renal neoplastic disorder with limited treatment options. It is characterized by the formation of large fluid-filled cysts that develop from kidney tubules through abnormal cell proliferation and cyst-filling fluid secretion driven by cAMP-dependent Cl− secretion. We have examined the effectiveness of the indazole carboxylic acid, H2-gamendazole (H2-GMZ), a derivative of lonidamine, to inhibit these processes and cyst formation using in vitro and in vivo models of ADPKD. H2-GMZ was effective in rapidly blocking forskolin-induced, Cl−-mediated short-circuit currents in human ADPKD cells at 1 μM and it significantly inhibited both cAMP- and EGF-induced proliferation of ADPKD cells with an IC50 of 5-10 μM. Western blot analysis of H2-GMZ-treated ADPKD cells showed decreased phosphorylated ERK and hyperphosphorylated Rb levels. H2-GMZ treatment also decreased ErbB2, Akt, and Cdk4, consistent with inhibition of the chaperone Hsp90, and reduced the levels of the CFTR Cl− channel. H2-GMZ-treated ADPKD cultures contained a higher proportion of smaller cells with fewer and smaller lamellipodia and decreased cytoplasmic actin staining, and they were unable to accomplish wound closure even at low H2-GMZ concentrations, consistent with an alteration in the actin cytoskeleton and decreased cell motility. Studies using mouse metanephric organ cultures showed that H2-GMZ inhibited cAMP-stimulated cyst growth and enlargement. In vivo, H2-GMZ (20mg/kg) was effective in slowing postnatal cyst formation and kidney enlargement in the Pkd1flox/flox:Pkhd1-Cre mouse model. Thus, H2-GMZ treatment decreases Cl− secretion, cell proliferation, cell motility, and cyst growth. These properties, along with its reported low toxicity, suggest that H2-GMZ might be an attractive candidate for treatment of ADPKD.


2019 ◽  
Vol 12 (8) ◽  
pp. 644-653 ◽  
Author(s):  
Tijmen H Booij ◽  
Wouter N Leonhard ◽  
Hester Bange ◽  
Kuan Yan ◽  
Michiel Fokkelman ◽  
...  

Abstract Polycystic kidney disease (PKD) is a prevalent genetic disorder, characterized by the formation of kidney cysts that progressively lead to kidney failure. The currently available drug tolvaptan is not well tolerated by all patients and there remains a strong need for alternative treatments. The signaling rewiring in PKD that drives cyst formation is highly complex and not fully understood. As a consequence, the effects of drugs are sometimes difficult to predict. We previously established a high throughput microscopy phenotypic screening method for quantitative assessment of renal cyst growth. Here, we applied this 3D cyst growth phenotypic assay and screened 2320 small drug-like molecules, including approved drugs. We identified 81 active molecules that inhibit cyst growth. Multi-parametric phenotypic profiling of the effects on 3D cultured cysts discriminated molecules that showed preferred pharmacological effects above genuine toxicological properties. Celastrol, a triterpenoid from Tripterygium Wilfordii, was identified as a potent inhibitor of cyst growth in vitro. In an in vivo iKspCre-Pkd1lox,lox mouse model for PKD, celastrol inhibited the growth of renal cysts and maintained kidney function.


2020 ◽  
Vol 21 (12) ◽  
pp. 4537
Author(s):  
Svenja Koslowski ◽  
Camille Latapy ◽  
Pierrïck Auvray ◽  
Marc Blondel ◽  
Laurent Meijer

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inheritable cause of end stage renal disease and, as of today, only a single moderately effective treatment is available for patients. Even though ADPKD research has made huge progress over the last decades, the precise disease mechanisms remain elusive. However, a wide variety of cellular and animal models have been developed to decipher the pathophysiological mechanisms and related pathways underlying the disease. As none of these models perfectly recapitulates the complexity of the human disease, the aim of this review is to give an overview of the main tools currently available to ADPKD researchers, as well as their main advantages and limitations.


1995 ◽  
Vol 43 (8) ◽  
pp. 785-790 ◽  
Author(s):  
M R Ogborn ◽  
S Sareen ◽  
K Tomobe ◽  
H Takahashi ◽  
J F Crocker

Apical mislocation of the ubiquitous transport enzyme Na,K-ATPase has been implicated as a feature of cyst development in in vitro studies of human polycystic kidney disease (PKD) epithelia. We undertook an immunohistochemical study of murine glucocorticoid-induced PKD, the pcy mouse, the cpk mouse, and the diphenylthiazole (DPT)-induced rat models of PKD to determine if this feature was common to these models of cyst development. Distribution of Na,K-ATPase was determined with a polyclonal anti-Na,K-ATPase antibody and a nickel-silver-enhanced peroxidase color development system. Results were documented objectively with densitometric techniques. Control animals appropriate to the age, strain, and species of the experimental groups demonstrated the expected polar distribution of Na,K-ATPase to the basolateral surface. This distribution was more marked in mature animals. Tubular dilatation and cystic change, however, were associated with increased apical Na,K-ATPase in all models. The murine models demonstrated decreased basolateral staining for Na,K-ATPase compared with controls, although this was not a feature of the DPT rat model. Abnormal location of Na,K-ATPase is a shared feature of a variety of animal models and human PKD. This may contribute to abnormal fluid and electrolyte flux favoring cyst formation or may represent expression of a less differentiated renal tubule epithelial phenotype.


1996 ◽  
Vol 270 (1) ◽  
pp. C389-C399 ◽  
Author(s):  
K. Hanaoka ◽  
O. Devuyst ◽  
E. M. Schwiebert ◽  
P. D. Wilson ◽  
W. B. Guggino

Human autosomal dominant polycystic kidney disease (ADPKD) is the most common lethal dominant hereditary disorder characterized by enormous renal enlargement and the development of multiple cysts originating from nephrons. We investigated the pathogenesis of cyst formation in ADPKD by using patch-clamp and immunocytochemical techniques. Adenosine 3',5'-cyclic monophosphate-activated Cl- currents are present in primary cultures of ADPKD cells and have characteristics such as a linear current-voltage relation, insensitivity to 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid, sensitivity to glibenclamide and diphenylamine carboxylic acid, and an anion selectivity sequence of Br- > Cl- > I- > glutamate, all of which are identical to cystic fibrosis transmembrane conductance regulator (CFTR). With the use of CFTR antibodies raised against the regulatory and first nucleotide-binding domains, CFTR was detected in primary cultures of ADPKD cells. Similar results were obtained in vivo in cyst-lining epithelial cells in ADPKD kidneys, where staining was seen associated with the apical membrane regions. These data indicate that the CFTR Cl- channel exists in apical membranes of ADPKD cells and may play an important role in cyst formation or enlargement.


2021 ◽  
pp. 1-9
Author(s):  
Ling Lu ◽  
Qiuling Liu ◽  
Lei Zhi ◽  
Xuchun Che ◽  
Bo Xiao ◽  
...  

<b><i>Background:</i></b> Polycystic kidney disease (PKD) represents the most prevalent inherited progressive kidney disorder in humans. Due to complexity of the genetic network behind the disease, the molecular mechanisms of PKD are still poorly understood yet. <b><i>Objectives:</i></b> This study aimed to develop a ciliogenesis-associated gene network for PKD patients and comprehensively understand the molecular mechanisms underlying the disease. <b><i>Method:</i></b> The potential hub genes were selected based on the differential expression analysis from the GEO database. Meanwhile, the primary hub genes were further elucidated by both in vivo and in vitro experiments. <b><i>Results:</i></b> In this study, we established a comprehensive differentially expressed genes profile (including <i>GNAS, PI4KB, UMOD, SLC7A13,</i> and <i>MIOX</i>) for PKD patients compared with the control specimen. At the same time, enrichment analysis was utilized to demonstrate that the G-protein-related signaling and cilia assembling signaling pathways were closely associated with PKD development. The further investigations of the interaction between 2 genes (<i>GNAS</i> and <i>PI4KB</i>) with in vivo and in vitro analyses revealed that PI4KB functioned as a downstream factor for GNAS and spontaneously activated the phosphorylation of Akt into p-Akt for ciliogenesis in PKD formation. The <i>PI4KB</i> depletion mutant zebrafish model displayed a PKD phenotype as well as absence of primary cilia in the kidney<i>.</i> <b><i>Conclusions:</i></b> Collectively, our work discovered an innovative potential signaling pathway model for PKD formation, which provided a valuable insight for future study of the mechanism of this disease.


2006 ◽  
Vol 26 (4) ◽  
pp. 1538-1548 ◽  
Author(s):  
Caroline Thivierge ◽  
Almira Kurbegovic ◽  
Martin Couillard ◽  
Richard Guillaume ◽  
Olivier Coté ◽  
...  

ABSTRACT The pathogenetic mechanisms underlying autosomal dominant polycystic kidney disease (ADPKD) remain to be elucidated. While there is evidence that Pkd1 gene haploinsufficiency and loss of heterozygosity can cause cyst formation in mice, paradoxically high levels of Pkd1 expression have been detected in the kidneys of ADPKD patients. To determine whether Pkd1 gain of function can be a pathogenetic process, a Pkd1 bacterial artificial chromosome (Pkd1-BAC) was modified by homologous recombination to solely target a sustained Pkd1 expression preferentially to the adult kidney. Several transgenic lines were generated that specifically overexpressed the Pkd1 transgene in the kidneys 2- to 15-fold over Pkd1 endogenous levels. All transgenic mice reproducibly developed tubular and glomerular cysts and renal insufficiency and died of renal failure. This model demonstrates that overexpression of wild-type Pkd1 alone is sufficient to trigger cystogenesis resembling human ADPKD. Our results also uncovered a striking increased renal c-myc expression in mice from all transgenic lines, indicating that c-myc is a critical in vivo downstream effector of Pkd1 molecular pathways. This study not only produced an invaluable and first PKD model to evaluate molecular pathogenesis and therapies but also provides evidence that gain of function could be a pathogenetic mechanism in ADPKD.


2015 ◽  
Vol 308 (9) ◽  
pp. F1004-F1011 ◽  
Author(s):  
EunSun Chang ◽  
Eun Young Park ◽  
Yu mi Woo ◽  
Duk-Hee Kang ◽  
Young-Hwan Hwang ◽  
...  

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by abnormal proliferation of renal tubular epithelial cells, resulting in the loss of renal function. Despite identification of the genes responsible for ADPKD, few effective drugs are currently available for the disease. Thus finding additional effective drug targets is necessary. The functions of multidrug- resistance-associated protein 3 (MRP3) have been reported only in the field of drug resistance, and the renal functions of MRP3 are mostly unknown. In this study, we found that MRP3 was significantly downregulated in kidneys of human patients with ADPKD and polycystic kidney disease (PKD) mouse models. Our results suggest that downregulated MRP3 stimulated renal epithelial cell proliferation through the B-Raf/MEK/ERK signaling pathway. In contrast, we found that restoring MRP3 reduced cell proliferation and cystogenesis in vitro. These results suggest that the renal function of MRP3 is related to renal cell proliferation and cyst formation and that restoring MRP3 may be an effective therapeutic approach for PKD.


Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 532
Author(s):  
Jennifer Q. J. Zhang ◽  
Sayanthooran Saravanabavan ◽  
Gopala K. Rangan

The DNA damage response (DDR) pathway is upregulated in autosomal dominant polycystic kidney disease (ADPKD) but its functional role is not known. The ataxia-telangiectasia mutated (ATM) and AT and Rad3-related (ATR) protein kinases are key proximal transducers of the DDR. This study hypothesized that reducing either ATM or ATR attenuates kidney cyst formation and growth in experimental ADPKD. In vitro, pharmacological ATM inhibition by AZD0156 reduced three-dimensional cyst growth in MDCK and human ADPKD cells by up to 4.4- and 4.1-fold, respectively. In contrast, the ATR inhibitor, VE-821, reduced in vitro MDCK cyst growth but caused dysplastic changes. In vivo, treatment with AZD0156 by oral gavage for 10 days reduced renal cell proliferation and increased p53 expression in Pkd1RC/RC mice (a murine genetic ortholog of ADPKD). However, the progression of cystic kidney disease in Pkd1RC/RC mice was not altered by genetic ablation of ATM from birth, in either heterozygous (Pkd1RC/RC/Atm+/−) or homozygous (Pkd1RC/RC/Atm−/−) mutant mice at 3 months. In conclusion, despite short-term effects on reducing renal cell proliferation, chronic progression was not altered by reducing ATM in vivo, suggesting that this DDR kinase is dispensable for kidney cyst formation in ADPKD.


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