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Autosomal dominant polycystic kidney disease (ADPKD). A, A 39-year-old ADPKD female patient with enlarged, polycystic kidneys and liver; computed tomography with iodinated contrast, showing multiple hepatic (arrows) and renal cysts (arrowheads) of variable sizes. B, A 32-year-old male patient with ADPKD; magnetic resonance with gadolinium contrast, displaying bilateral multiple cysts (arrowheads) distributed throughout the kidneys.
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Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common human life-threatening monogenic disorders. The disease is characterized by bilateral, progressive renal cystogenesis and cyst and kidney enlargement, often leading to end-stage renal disease, and may include extrarenal manifestations. ADPKD is caused by mutation in one...
Citations
... In proof-of-principle studies, we applied U-ExM to healthy human from nephrectomies and from patients with Autosomal Dominant Polycystic Kidney Disease (ADPKD). ADPKD is a well-established ciliopathy that is characterized by defects in a) ciliary structure and function, b) changes in epithelial cell growth, polarity, and cytoskeletal organization, c) the development of large fluid filled cysts that destroys the renal parenchyma, and d) fibrosis and extracellular matrix (ECM) deposition that leads to renal failure (Bastos & Onuchic, 2011;Fragiadaki et al., 2020;Grantham et al., 2011;Hou et al., 2002;Lee & Somlo, 2014;Ma et al., 2017;Norman, 2011;Song et al., 2017;Wilson, 2004;Wilson et al., 1992;Yoder et al., 2002). ...
Ultrastructure expansion microscopy (U-ExM) involves the physical magnification of specimens embedded in hydrogels, which allows for super-resolution imaging of subcellular structures using a conventional diffraction-limited microscope. Methods for expansion microscopy exist for several organisms, organs, and cell types, and used to analyze cellular organelles and substructures in nanoscale resolution. Here, we describe a simple step-by-step U-ExM protocol for the expansion, immunostaining, imaging, and analysis of cytoskeletal and organellar structures in kidney tissue. We detail the critical modified steps to optimize isotropic kidney tissue expansion, and preservation of the renal cell structures of interest. We demonstrate the utility of the approach using several markers of renal cell types, centrioles, cilia, the extracellular matrix, and other cytoskeletal elements. Finally, we show that the approach works well on mouse and human kidney samples that were preserved using different fixation and storage conditions. Overall, this protocol provides a simple and cost-effective approach to analyze both pre-clinical and clinical renal samples in high detail, using conventional lab supplies and standard widefield or confocal microscopy.
... Defects in this gene are known to lead to renal tubular acidosis(Smith et al. 2000). Mutations to the transmembrane protein encoded by PKHD1 cause autosomal recessive polycystic kidney disease(Bastos and Onuchic 2011). APP (Amyloid Beta Precursor Protein) is best known for its role in Alzheimer Disease. ...
The use of calcineurin inhibitors has revolutionized solid organ transplantation increasing survival rates dramatically. However, calcineurin inhibitor induced nephrotoxicity severely limits the use of this class of drugs in transplantation and other diseases. Here we set out to define a microRNA (miRNA)-messenger RNA (mRNA) interaction map to identify the role of miRNAs in cyclosporine-induced nephrotoxicity and the gene pathways they regulate. By integrating miRNA and mRNA expression profiling with photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation (PARCLIP) against endogenous Argonaute 2 (AGO2) protein in human proximal tubule cells, we identified miRNAs and mRNAs undergoing active targeting in cyclosporine A (CsA) treated-cells and vehicle-treated controls. First, expression profiling of miRNAs and mRNAs in CsA-treated versus vehicle-treated cells identified the key canonical pathways and cellular processes which are dysregulated in proximal tubule epithelial cells (PTECs) by CsA. Our data support a model whereby CsA induces and epithelial-to-mesenchymallike (EMT-like) re-programming of PTECs by down-regulation of key apical surface, cell junction, and adherens junction genes as well as up-regulation of major pro-EMT cell signaling pathways such as PI3K/AKT, ERK, and TGF-β. Our data indicate that CsA causes specific changes in miRNAs and mRNAs associated with the RNA-Induced Silencing Complex (RISC) complex. Pathway enrichment analysis identified canonical pathways specifically under regulation by miRNAs following CsA treatment. Analysis of active miRNA-mRNA targeting interactions revealed that CsA suppresses an upstream regulator of JNK and p38 MAPKs by inducing targeting of MAP3K1 by miR-101-3p thereby uncovering a previously undefined mechanism by which CsA affects calcineurinindependent molecular pathways. These insights into the molecular pathways governing expression of genes involved in cyclosporine-induced nephrotoxicity may provide novel therapeutic approaches to preventing chronic renal injury in transplant recipients.
... ADPKD is the most common genetic renal disease[1]that affects approximately 4 to 7 million individuals[2]. Mutations in polycystins 1 and 2 impair homeostasis and intracellular calcium signaling, which subsequently cause cyst formation, inflammation, and fibrosis in the kidneys[3,4]. Despite recent advances in the identification of ADPKD pathogenesis, current treatments have been unable to completely cure or control disease progression. ...
Background
Autosomal dominant polycystic kidney disease (ADPKD) is a genetic ciliopathy disease characterized by progressive formation and enlargement of cysts in multiple organs. The kidneys are particularly affected and patients may eventually develop end-stage renal disease (ESRD). We hypothesize that bone marrow mesenchymal stromal cells (BMMSCs) are renotropic and may improve kidney function via anti-apoptotic, anti-fibrotic, and anti-inflammatory effects. In this study, we aim to assess the safety and tolerability of a BMMSC infusion in ADPKD patients.
Methods
We performed a single-arm phase I clinical trial with a 12-month follow-up. This study enrolled six eligible ADPKD patients with an estimated glomerular filtration rate (eGFR) of 25–60 ml/min/1.73 m². Patients received autologous cultured BMMSCs (2 × 10⁶ cells/kg) through the cubital vein according to our infusion protocol. We investigated safety issues and kidney function during the follow-up visits, and compared the findings to baseline and 1 year prior to the intervention.
Results
There were no patients lost to follow-up. We observed no cell-related adverse events (AE) and serious adverse events (SAE) after 12 months of follow-up. The mean eGFR value of 33.8 ± 5.3 ml/min/1.73 m² 1 year before cell infusion declined to 26.7 ± 3.1 ml/min/1.73 m² at baseline (P = 0.03) and 25.8 ± 6.2 ml/min/1.73 m² at the 12-month follow-up visit (P = 0.62). The mean serum creatinine (SCr) level of 2 ± 0.3 mg/dl 1 year before the infusion increased to 2.5 ± 0.4 mg/dl at baseline (P = 0.04) and 2.5 ± 0.6 mg/dl at the 12-month follow-up (P = 0.96). This indicated significant changes between the differences of these two periods (12 months before infusion to baseline, and 12 months after infusion to baseline) in SCr (P = 0.05), but not eGFR (P = 0.09).
Conclusions
This trial demonstrated the safety and tolerability of an intravenous transplantation of autologous BMMSCs. BMMSC efficacy in ADPKD patients should be investigated in a randomized placebo-controlled trial with a larger population, which we intend to perform.
Trial registration
ClinicalTrials.gov, NCT02166489. Registered on June 14, 2014.
Electronic supplementary material
The online version of this article (doi:10.1186/s13287-017-0557-7) contains supplementary material, which is available to authorized users.
... ADPKD is the most common genetic renal disease[1]that affects approximately 4 to 7 million individuals[2]. Mutations in polycystins 1 and 2 impair homeostasis and intracellular calcium signaling, which subsequently cause cyst formation, inflammation, and fibrosis in the kidneys[3,4]. Despite recent advances in the identification of ADPKD pathogenesis, current treatments have been unable to completely cure or control disease progression. ...
Cilia are microtubule-based organelles, protruding from the apical cell surface and anchoring to the cytoskeleton. Primary (nonmotile) cilia of the kidney act as mechanosensors of nephron cells, responding to fluid movements by triggering signal transduction. The impaired functioning of primary cilia leads to formation of cysts which in turn contribute to development of diverse renal diseases, including kidney ciliopathies and renal cancer. Here, we review current knowledge on the role of ciliary genes in kidney ciliopathies and renal cell carcinoma (RCC). Special focus is given on the impact of mutations and altered expression of ciliary genes (e.g., encoding polycystins, nephrocystins, Bardet-Biedl syndrome (BBS) proteins, ALS1, Oral-facial-digital syndrome 1 (OFD1) and others) in polycystic kidney disease and nephronophthisis, as well as rare genetic disorders, including syndromes of Joubert, Meckel-Gruber, Bardet-Biedl, Senior-Loken, Alström, Orofaciodigital syndrome type I and cranioectodermal dysplasia. We also show that RCC and classic kidney ciliopathies share commonly disturbed genes affecting cilia function, including VHL (von Hippel-Lindau tumor suppressor), PKD1 (polycystin 1, transient receptor potential channel interacting) and PKD2 (polycystin 2, transient receptor potential cation channel). Finally, we discuss the significance of ciliary genes as diagnostic and prognostic markers, as well as therapeutic targets in ciliopathies and cancer.
The primary cilium is a microtubule-based organelle that is considered to be a cellular antennae, because proteins related to multiple signaling pathways such as Wnt, PDGFRα, Hh, and mechanosignaling are localized to the membrane of the primary cilium. In the kidney, primary cilia extend from the cell membrane to the lumen of renal tubules to respond to fluidic stress. Recent studies have indicated that the disruption of ciliary proteins including polycystin-1 (PC1), polycystin-2 (PC2), and members of the intraflagellar transport (IFT) family induce the development of polycystic kidney disease (PKD), suggesting that the malformation or absence of primary cilia is a driving force of the onset of PKD. Therefore, in this chapter, the renal cystogenesis mechanism induced by cilia defects and pathogenic ciliary proteins associated with PKD development will be described.
Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary cause of chronic kidney disease stage 5 and represents 3% to 10.3% among patients undergoing dialysis in Brazil. The ADPKD is caused by mutations in one of two genes, PKD1 or PKD2 encoding hence the polycystins 1 and 2 involved in cyst formation. The disease is characterized by progressive growth and development of multiple bilateral renal cysts which lead to loss of kidney function. The ADPKD presents several renal and extrarenal clinical manifestations, and comorbidities. Some diagnostic strategies are regarded as first choice for clinical and molecular investigation of the ADPKD. The knowledge of molecular aspects in association with the clinical manifestations presented by the epidemiology of the disease provides better understanding of the mechanisms of cystogenesis and greater diagnostic accuracy.
Positron-emission tomography/computed tomography (PET/CT) has improved cyst infection (CI) management in autosomal dominant polycystic kidney disease (ADPKD). The determinants of kidney and/or liver involvement, however, remain uncertain. In this study, we evaluated clinical and imaging factors associated with CI in kidney (KCI) and liver (LCI) in ADPKD. A retrospective cohort study was performed in hospital-admitted ADPKD patients with suspected CI. Clinical, imaging and surgical data were analyzed. Features of infected cysts were evaluated by PET/CT. Total kidney (TKV) and liver (TLV) volumes were measured by CT-derived multiplanar reconstruction. CI was detected in 18 patients who experienced 24 episodes during an interval of 30 months (LCI in 12, KCI in 10 and concomitant infection in 2). Sensitivities of CT, magnetic resonance imaging and PET/CT were 25.0, 71.4, and 95.0%. Dysuria (P<0.05), positive urine culture (P<0.01), and previous hematuria (P<0.05) were associated with KCI. Weight loss (P<0.01) and increased C-reactive protein levels (P<0.05) were associated with LCI. PET/CT revealed that three or more infected cysts were present in 70% of the episodes. TKV was higher in kidney-affected than in LCI patients (AUC=0.91, P<0.05), with a cut-off of 2502 mL (72.7% sensitivity, 100.0% specificity). TLV was higher in liver-affected than in KCI patients (AUC=0.89, P<0.01) with a cut-off of 2815 mL (80.0% sensitivity, 87.5% specificity). A greater need for invasive procedures was observed in LCI (P<0.01), and the overall mortality was 20.8%. This study supports PET/CT as the most sensitive imaging method for diagnosis of cyst infection, confirms the multifocal nature of most hospital-admitted episodes, and reveals an association of kidney and liver volumes with this complication.
Introduction:
Autosomal dominant polycystic kidney disease is the most common hereditary renal disease in humans.
Objective:
To examine the prevalence, clinical and laboratory characteristics of patients with polycystic kidneys and relate disease manifestations by gender.
Methods:
This was an observational and retrospective study. All the medical records of patients with polycystic kidneys who initiated hemodialysis between 1995 and 2012, in four centers that treat patients of the coverage area of the 15th regional health Paraná (Brazil), were analyzed.
Results:
The study included 48 patients with polycystic kidneys, the primary cause of stage 5 CKD. Disease prevalence was one in 10,912 people. The average age of dialysis initiation was 50.7 years and the follow-up time on dialysis until transplantation (36.5 months) was lower among men. Hypertension was the most frequent diagnosis in 73% of patients, predominantly in women (51.4%). The liver cyst was the most frequent extrarenal manifestations in men (60.0%). The death occurred in 10.4% of patients using hemodialysis, and 60% of men. The class of antihypertensive drug used was that acts on the renin-angiotensin system with higher frequency of use among women (53.3%). The post-dialysis urea was significantly higher in men.
Conclusion:
The prevalence of the disease is low among hemodialysis patients in southern Brazil. The differences observed between genders, with the exception of the post-dialysis urea, were not significant. The findings are different from those reported in North America and Europe.
