Similar Datasets
Project description:Mitochondrial dysfunction is emerging as a crucial contributor to the pathogenesis of autosomal dominant polycystic kidney disease (ADPKD), but the molecular mechanisms underlying the disturbed mitochondrial homeostasis in cystic cells remain elusive. In the present study, we identify impaired activity of NRF2 antioxidant pathway as a driver mechanism for mitochondrial dysfunction and ADPKD progression. Using a quantitative proteomic approach, we find that NRF2 antioxidant pathway is suppressed in ADPKD kidneys. In a cohort of ADPKD patients, reactive oxygen species (ROS) levels are frequently elevated, and the increased ROS levels inversely correlates with decreased NRF2 expression and positively correlates with disease severity. Genetic deletion of NRF2 increases ROS generation and promotes cyst growth in an orthologous ADPKD mouse model, while pharmacological induction of NRF2 reduces ROS levels and retards cystogenesis and disease progression. Mechanistically, NRF2 activates its antioxidant target genes mainly through remodeling enhancer landscapes. The activation domain of NRF2 forms phase-separated condensates with MED16, a Mediator complex subunit in vitro, and NRF2 is required for optimal Mediator recruitment to target genomic sites in vivo. Taken together, these findings indicate that NRF2 remodels enhancer landscapes and activates its target genes through a phase-separation mechanism, and that activation of NRF2 represents a promising strategy for restoring mitochondrial homeostasis and combatting ADPKD.
2021-12-12 | PXD016312 | Pride
Project description:Oxidative stress is emerging as a crucial contributor to the pathogenesis of autosomal dominant polycystic kidney disease (ADPKD), but the molecular mechanisms underlying the disturbed redox homeostasis in cystic cells remain elusive. In the present study, we identify impaired activity of Nrf2 antioxidant pathway as a driver mechanism for oxidative damage and ADPKD progression. Using a quantitative proteomic approach, together with biochemistry analyses, we find that Nrf2 antioxidant pathway is suppressed due to increased degradation of Nrf2 protein in ADPKD kidneys. In a cohort of ADPKD patients, reactive oxygen species (ROS) levels are frequently elevated, and the ROS levels inversely correlates with Nrf2 abundance and positively correlates with disease severity. Genetic deletion of Nrf2 further increases ROS generation and promotes cyst growth in an orthologous ADPKD mouse model, while pharmacological induction of Nrf2 reduces ROS levels and retards cystogenesis and disease progression. Mechanistically, pharmacological induction of Nrf2 remodels enhancer landscapes and activates Nrf2-bound enhancer-associated genes in ADPKD cells. The activation domain of Nrf2 forms phase-separated condensates with Mediator subunit MED16 in vitro, and Nrf2 is required for optimal Mediator recruitment to target genomic loci in vivo. Taken together, these findings indicate that Nrf2 remodels enhancer landscapes and activates its target genes through a phase-separation mechanism, and that activation of Nrf2 represents a promising strategy for restoring redox homeostasis and combatting ADPKD.
2021-01-26 | GSE141740 | GEO
Project description:Oxidative stress is emerging as a crucial contributor to the pathogenesis of autosomal dominant polycystic kidney disease (ADPKD), but the molecular mechanisms underlying the disturbed redox homeostasis in cystic cells remain elusive. In the present study, we identify impaired activity of Nrf2 antioxidant pathway as a driver mechanism for oxidative damage and ADPKD progression. Using a quantitative proteomic approach, together with biochemistry analyses, we find that Nrf2 antioxidant pathway is suppressed due to increased degradation of Nrf2 protein in ADPKD kidneys. In a cohort of ADPKD patients, reactive oxygen species (ROS) levels are frequently elevated, and the ROS levels inversely correlates with Nrf2 abundance and positively correlates with disease severity. Genetic deletion of Nrf2 further increases ROS generation and promotes cyst growth in an orthologous ADPKD mouse model, while pharmacological induction of Nrf2 reduces ROS levels and retards cystogenesis and disease progression. Mechanistically, pharmacological induction of Nrf2 remodels enhancer landscapes and activates Nrf2-bound enhancer-associated genes in ADPKD cells. The activation domain of Nrf2 forms phase-separated condensates with Mediator subunit MED16 in vitro, and Nrf2 is required for optimal Mediator recruitment to target genomic loci in vivo. Taken together, these findings indicate that Nrf2 remodels enhancer landscapes and activates its target genes through a phase-separation mechanism, and that activation of Nrf2 represents a promising strategy for restoring redox homeostasis and combatting ADPKD.
2021-01-26 | GSE141739 | GEO
Project description:Nrf2-mediated enhancer activation ameliorates oxidative stress and cystogenesis in autosomal dominant polycystic kidney disease
| PRJNA594603 | ENA
Project description:Nrf2-mediated enhancer activation ameliorates oxidative stress and cystogenesis in autosomal dominant polycystic kidney disease [ChIP-seq]
| PRJNA594608 | ENA
Project description:Nrf2-mediated enhancer activation ameliorates oxidative stress and cystogenesis in autosomal dominant polycystic kidney disease [RNA-seq]
| PRJNA594607 | ENA
Project description:Autosomal-dominant polycystic kidney disease (ADPKD) is associated with progressive formation of renal cysts, kidney enlargement, hypertension, and typically end-stage renal disease. In ADPKD, inherited mutations disrupt function of the polycystins (encoded by PKD1 and PKD2), thus causing loss of a cyst-repressive signal emanating from the renal cilium. Genetic studies have suggested ciliary maintenance is essential for ADPKD pathogenesis. Heat shock protein 90 (HSP90) clients include multiple proteins linked to ciliary maintenance. We determined that ganetespib, a clinical HSP90 inhibitor, inhibited proteasomal repression of NEK8 and the Aurora-A activator trichoplein, rapidly activating Aurora-A kinase and causing ciliary loss in vitro. Using conditional mouse models for ADPKD, we performed long-term (10 or 50 wk) dosing experiments that demonstrated HSP90 inhibition caused durable in vivo loss of cilia, controlled cystic growth, and ameliorated symptoms induced by loss of Pkd1 or Pkd2. Ganetespib efficacy was not increased by combination with 2-deoxy-d-glucose, a glycolysis inhibitor showing some promise for ADPKD. These studies identify a new biologic activity for HSP90 and support a cilia-based mechanism for cyst repression.-Nikonova, A. S., Deneka, A. Y., Kiseleva, A. A., Korobeynikov, V., Gaponova, A., Serebriiskii, I. G., Kopp, M. C., Hensley, H. H., Seeger-Nukpezah, T. N., Somlo, S., Proia, D. A., Golemis, E. A. Ganetespib limits ciliation and cystogenesis in autosomal-dominant polycystic kidney disease (ADPKD).
| S-EPMC5901382 | biostudies-literature
Project description:Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations in either PKD1 or PKD2. It is one of the most common heritable human diseases with eventual development of renal failure; however, effective treatment is lacking. While inhibition of mechanistic target of rapamycin (mTOR) effectively slows cyst expansions in animal models, results from clinical studies are controversial, prompting further mechanistic studies of mTOR-based therapy. Here, we aim to establish autophagy, a downstream pathway of mTOR, as a new therapeutic target for PKD. We generated zebrafish mutants for pkd1 and noted cystic kidney and mTOR activation in pkd1a mutants, suggesting a conserved ADPKD model. Further assessment of the mutants revealed impaired autophagic flux, which was conserved in kidney epithelial cells derived from both Pkd1-null mice and ADPKD patients. We found that inhibition of autophagy by knocking down the core autophagy protein Atg5 promotes cystogenesis, while activation of autophagy using a specific inducer Beclin-1 peptide ameliorates cysts in the pkd1a model. Treatment with compound autophagy activators, including mTOR-dependent rapamycin as well as mTOR-independent carbamazepine and minoxidil, markedly attenuated cyst formation and restored kidney function. Finally, we showed that combination treatment with low doses of rapamycin and carbamazepine was able to attenuate cyst formation as effectively as a single treatment with a high dose of rapamycin alone. In summary, our results suggested a modifying effect of autophagy on ADPKD, established autophagy activation as a novel therapy for ADPKD, and presented zebrafish as an efficient vertebrate model for developing PKD therapeutic strategies.
| S-EPMC6251521 | biostudies-other
Project description:The human PKD2 locus encodes Polycystin-2 (PC2), a TRPP channel that localises to several distinct cellular compartments, including the cilium. PKD2 mutations cause Autosomal Dominant Polycystic Kidney Disease (ADPKD) and affect many cellular pathways. Data underlining the importance of ciliary PC2 localisation in preventing PKD are limited because PC2 function is ablated throughout the cell in existing model systems. Here, we dissect the ciliary role of PC2 by analysing mice carrying a non-ciliary localising, yet channel-functional, PC2 mutation. Mutants develop embryonic renal cysts that appear indistinguishable from mice completely lacking PC2. Despite not entering the cilium in mutant cells, mutant PC2 accumulates at the ciliary base, forming a ring pattern consistent with distal appendage localisation. This suggests a two-step model of ciliary entry; PC2 first traffics to the cilium base before TOP domain dependent entry. Our results suggest that PC2 localisation to the cilium is necessary to prevent PKD.
| S-EPMC6731238 | biostudies-literature
Project description:Autosomal-dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease and is characterized by progressive growth of fluid-filled cysts. Growth factors binding to receptor tyrosine kinases (RTKs) stimulate cell proliferation and cyst growth in PKD. Nintedanib, a triple RTK inhibitor, targets the vascular endothelial growth-factor receptor (VEGFR), platelet-derived growth-factor receptor (PDGFR), and fibroblast growth-factor receptor (FGFR), and is an approved drug for the treatment of non-small-cell lung carcinoma and idiopathic lung fibrosis. To determine if RTK inhibition using nintedanib can slow ADPKD progression, we tested its effect on human ADPKD renal cyst epithelial cells and myofibroblasts in vitro, and on Pkd1f/fPkhd1Cre and Pkd1RC/RC, orthologous mouse models of ADPKD. Nintedanib significantly inhibited cell proliferation and in vitro cyst growth of human ADPKD renal cyst epithelial cells, and cell viability and migration of human ADPKD renal myofibroblasts. Consistently, nintedanib treatment significantly reduced kidney-to-body-weight ratio, renal cystic index, cystic epithelial cell proliferation, and blood-urea nitrogen levels in both the Pkd1f/fPkhd1Cre and Pkd1RC/RC mice. There was a corresponding reduction in ERK, AKT, STAT3, and mTOR activity and expression of proproliferative factors, including Yes-associated protein (YAP), c-Myc, and Cyclin D1. Nintedanib treatment significantly reduced fibrosis in Pkd1RC/RC mice, but did not affect renal fibrosis in Pkd1f/fPkhd1Cre mice. Overall, these results suggest that nintedanib may be repurposed to effectively slow cyst growth in ADPKD.
| S-EPMC8517027 | biostudies-literature