RARE DISEASE
Juvenile nephronophthisis
Juvenile nephronophthisis
Juvenile nephronophthisis
Drug discovery
0
drugs
With orphan designations
Overview
Juvenile nephronophthisis (NPH) is an autosomal recessive ciliopathy characterized by chronic tubulointerstitial nephritis, corticomedullary cysts, and progressive renal fibrosis, leading to end-stage renal disease (ESRD) by median age 13. Key features include polyuria, polydipsia, anemia, and urine concentration defects. Over 20% of cases involve extrarenal manifestations such as retinal degeneration (Senior-Løken syndrome) or cerebellar anomalies (Joubert syndrome). Diagnosis relies on genetic testing (e.g., NPHP1 deletions) and renal ultrasound showing corticomedullary cysts [1][2][5][6].
Burden
Leading genetic cause of ESRD in children/young adults, requiring lifelong renal replacement therapy [5][6][19].
Extrarenal complications (e.g., liver fibrosis, neurological deficits) increase morbidity and diagnostic complexity [1][10][16].
High economic burden due to early-onset ESRD and multidisciplinary care needs [5][8][17].
Therapies
Supportive care: Hypertension management, anemia correction (e.g., erythropoietin), and electrolyte balancing [2][17].
Experimental targets: Vasopressin V2 receptor antagonists (e.g., tolvaptan) and CDK inhibitors (e.g., roscovitine) in preclinical models [3][8][13].
Renal replacement: Dialysis or transplantation (no disease recurrence post-transplant) [17][19].
Categories: rare genetic diseases, rare renal diseases, rare transplant-related disorders
Research Papers
40 drug discovery papers about Juvenile nephronophthisis, with 1 first-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
40 drug discovery papers about Juvenile nephronophthisis, with 1 first-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
categories:
Small molecules
cell therapies
2023-05-24 | A case report of two Chinese monozygotic twins with NPHP1 gene-associated nephronophthisis undergoing kidney transplantation from a related living-donor.
Nephronophthisis (NPHP) is an autosomal recessive cystic kidney disease and the most common hereditary disease leading to end-stage renal disease in children and adolescents. The NPHP1 gene was the first NPHP gene to be discovered. Pathogenic variation of the NPHP1 gene can cause juvenile renal wasting disease type 1. Here, we report the first case of living related kidney transplantation of monozygotic twins with NPHP1 nephronophthisis in China; one of these cases involved cross-blood type kidney transplantation. Our experience shows that patients with NPHP1 nephronophthisis have almost no risk recurrent kidney disease following living related kidney transplantation and genetic testing. The two twins recovered well without any complications. This is the first report of living related kidney transplantation of monozygotic twins with heterozygous deletion of the NPHP1 gene in a Chinese family with NPHP. In addition, genetic testing provides an efficient means of evaluating the safety of living related kidney transplantation in patients with NPHP1 nephronophthisis.
2021-10-13 | Living-Related Kidney Transplantation in a Patient with Juvenile Nephronophthisis.
Nephronophthisis (NPHP) is an autosomal recessive disease manifesting as tubulointerstitial nephritis uniformly progressing to ESRD in approximately 5-10% patients in childhood. Living donor transplantation is the most beneficial mean of renal replacement therapy compared to other methods. However, living kidney donation is contraindicated in potential donor with diseases of autosomal dominant mode of inheritance potentially leading to kidney failure in future. On the other hand, autosomal recessive genetic kidney diseases, such as NPHP, are not usually contraindication to living kidney donation. Herein, we are reporting related living kidney transplantation with a family history of NPHP form 46-year-old mother (heterozygote) to 17-year-old daughter with (autosomal recessive homozygote) with focus on donor follow-up after nephrectomy.
2021-06-21 | Generation of two human induced pluripotent stem cell lines derived from two juvenile nephronophthisis patients with NPHP1 deletion.
Juvenile nephronophthisis is an inherited renal ciliopathy, causing cystic kidney disease, renal fibrosis, and end-stage renal failure. Human induced pluripotent stem cell (hiPSC) lines, derived from two Juvenile nephronophthisis patients, were generated from peripheral blood mononuclear cells by episomal plasmid vectors. Generated hiPSC lines showed self-renewal and pluripotency and carried a large deletion in NPHP1 (Nephrocystin 1) gene. Since the molecular pathogenesis caused by NPHP1 dysfunction remains unclear, these cell resources provide useful tools to establish disease models and to develop new therapies for juvenile nephronophthisis.
2006-11-14 | Persistent post-transplant polyuria managed by bilateral native-kidney laparoscopic nephrectomy.
Polyuria is not considered an absolute indication for pre-transplant nephrectomy; however, it may complicate post-transplantation fluid management. Bilateral native-kidney laparoscopic nephrectomy was performed at our centre in two patients (four kidneys) 1 month after they had received a living related-donor renal transplant. The indication for nephrectomy was severe post-transplant polyuria secondary to the patient's underlying disease: juvenile nephronophthisis. Both patients had a persistent post-transplant daily urine output of 7-8 l/day and continued to have a variable serum creatinine level, dependent on intravenous hydration, more then 3 weeks after transplantation. Bilateral laparoscopic native-kidney nephrectomy in children has previously been reported. However, to the best of our knowledge, laparoscopic nephrectomy has not been described after kidney transplantation and certainly not in the immediate post-transplantation period. The procedure was well tolerated and did not affect renal graft function. In fact, following the procedure, serum creatinine levels stabilized, while daily fluid requirements decreased to 2.5-3.5 l/day in both patients. We concluded that bilateral native-kidney nephrectomy can be safely performed in paediatric renal transplant recipients in the immediate post-transplantation period. This new approach may allow preemptive transplantation and avoid the need for a transition period on dialysis in patients for whom pre-transplant nephrectomy is not absolutely indicated.
1987-08-01 | Renal transplantation in children with oculorenal sydnrome
The association of tapetoretinal degeneration with familial juvenile nephronophthisis is a rare oculorenal syndrome. Without treatment all children die of renal failure prior to adulthood. Information regarding renal transplantation is lacking in these children. This article reflects our experience in two children affected with this syndrome who achieved excellent functional results following living-related kidney transplants. Surgery can be done safely in these children with little or no morbidity. We believe that children with this syndrome benefit from transplantation and that this offers a significant improvement in their quality of life.
small molecules
2026-06-24 | Spatiotemporal dynamics of renal distal convoluted tubule dilatation and cyst formation in nephronophthisis type 1 mice.
Nephronophthisis (NPH), a rare but serious ciliopathy, is the predominant genetic cause of end-stage kidney disease (ESKD) in children and adolescents. Renal tubular dilatation and cyst formation are key pathological features of NPH. The mechanisms underlying renal cystogenesis remain poorly understood. This study employed sex-balanced Nphp1 deletion gene knockout (Nphp1KO) mice at 8, 12, and 24 weeks of age to investigate the spatiotemporal dynamics of renal tubules and cyst development, aiming to identify the origins of renal cysts. Quantitative evaluation of cyst progression revealed a significant increase in cyst number from 8 to 12 weeks of age, but no substantial change from 12 to 24 weeks. Additionally, cyst size remained stable throughout the study period. Serial section tracing and segment-specific tubular marker analysis confirmed that these cysts originated from the distal convoluted tubule (DCT), which displayed segmental dilation while preserving anatomical connections with adjacent, morphologically normal DCT. 3D reconstruction revealed that renal cysts appeared either as a single or in a bead-like arrangement. We demonstrated that human renal cyst epithelial cells from patients with NPH1 also originate primarily from the DCT. This study provides critical experimental evidence of the histopathological features of renal cysts in NPH1, advancing our understanding of the pathogenesis of NPHP-associated tubular dilation and cystogenesis.
2026-05-26 | Developmental switch dichotomizes kidney response to Nphp3 inactivation and treatment outcome
ABSTRACT Nephronophthisis (NPH) is n rare recessive kidney disease caused by biallelic variants in more than 25 NPHP genes encoding proteins that localize to primary cilia. It is characterized by three different forms depending on the age of onset and kidney lesions: infantile (cystic), juvenile/late onset (fibrotic). To date, the pathways linking altered primary cilia function to progressive kidney scarring in NPH remain poorly defined and therapeutic options are lacking. To address these questions, we generated two new mouse NPH models by inactivating Nphp3 specifically in kidney tubules either during embryogenesis or in adult, recapitulating the infantile and juvenile forms of the disease, respectively. Embryonic inactivation produced a rapid and severe cystic phenotype with tubular dedifferentiation, progressive interstitial fibrosis, inflammation and kidney failure, while postnatal inactivation led to a slowly progressive tubulointerstitial nephropathy characterized by tubular atrophy, fibrosis and immune cell infiltration without cyst formation. Strikingly, cilia were preserved in the early stages of both models, indicating that ciliogenesis impairment is not a primary driver of NPH3 pathogenesis. Transcriptomic profiling of the juvenile model revealed that disease initiation is driven by mitochondrial dysfunction, innate immune activation and aberrant cell cycle progression, while epithelial-to-mesenchymal transition and Wnt/β-catenin remodelling emerges only at later stages of disease progression. Therapeutic intervention with the PGE1 (alprostadil) failed to rescue the cystic/infantile model but significantly attenuated fibrosis, inflammation and interstitial fibrosis in the fibrotic/juvenile model. The ability to recapitulate both disease forms through temporal modulation of gene inactivation suggests that primary cilia serve distinct, stage-specific functions in kidney tubular homeostasis, with different cellular processes being selectively vulnerable depending on the causative gene or variant. Collectively, these findings uncover early pathogenic mechanisms that may constitute tractable therapeutic targets for the treatment of nephronophthisis.
2026-03-28 | Renal Tubule-Specific Deletion of Nephrocystin 3 (Nphp3) Causes Infantile Nephronophthisis-like Phenotypes in Mice.
Patients with nephronophthisis caused by nephrocystin 3 (NPHP3) variants rapidly progress to end-stage kidney disease. However, existing Nphp3 mouse models fail to fully recapitulate the characteristics of this disease. We generated a renal tubule-specific Nphp3 knockout mouse model that more accurately mirrors the human disease course. The mouse model was first validated by confirming the loss of Nphp3 protein expression in renal tubules. Comprehensive phenotypic analyses were then performed to assess both renal and extrarenal manifestations. The origin of renal cysts was investigated, and the underlying mechanisms were further validated. We successfully generated a renal tubule-specific Nphp3 knockout mouse model (Cdh16-Cre; Nphp3flox/flox). These mice exhibited a markedly shortened lifespan (5-8 weeks) and developed key features of infantile nephronophthisis, including early-onset renal cysts originating from distal tubules and collecting ducts, progressive interstitial fibrosis that was evident by postnatal week 2, a rapid decline in kidney function, and increased urinary protein levels. Importantly, treatment with the vasopressin V2 receptor antagonist tolvaptan or the mitogen-activated extracellular signal-regulated kinase (MEK) inhibitor 2-(2-chloro-4-iodoanilino)-N-(cyclopropylmethoxy)-3,4-difluorobenzamide (CI-1040) significantly attenuated cyst growth and improved kidney morphology, confirming shared pathogenic pathways with other Nphp3 models. We established a renal tubule-specific Nphp3 knockout mouse model that accurately recapitulates the aggressive infantile form of nephronophthisis characterized by early cystogenesis, progressive fibrosis, and a shortened lifespan, and is ideal for evaluating novel interventions against this currently untreatable ciliopathy.
2025-08-08 | Urinary renal epithelial cells can be used for NPHP1 phenotyping and a personalized therapeutic strategy.
Nephronophthisis (NPHP) is a recessive tubulointerstitial nephropathy and a leading genetic cause of kidney failure in children and young adults. The most common genetic cause is a homozygous deletion of NPHP1, which encodes nephrocystin-1, a protein essential for primary cilium structure and cell junctions. Using personalized medicine and deep phenotyping, we investigated a family with three siblings carrying a homozygous NPHP1 deletion. We compared kidney biopsy tissue and human urine-derived renal epithelial cells (hURECs) from these individuals. Bulk RNA-seq on patient hURECs revealed altered expression in EGFR signalling, extracellular components and adherens junctions, which is consistent with the known roles for nephrocystin-1. Treatment with alprostadil, a proposed NPHP therapy, increased ciliation but worsened ciliary elongation. By contrast, the EGFR kinase inhibitor AG556 rescued of ciliary length and morphology. Transcriptional profiling post-treatment showed AG556 reversed the disease signature more effectively that alprostadil. These findings suggest that EGFR inhibition might offer a more promising therapeutic strategy for NPHP1-associated renal ciliopathy, warranting further testing in in vivo models before clinical application.
2025-07-28 | The nephronophthisis protein GLIS2/NPHP7 is required for the DNA damage response in kidney tubular epithelial cells.
Nephronophthisis (NPH) is an autosomal-recessive cystic kidney disease representing the most frequent genetic cause of end-stage kidney failure in children and adolescents. NPH is caused by genetic variants in >20 NPHP genes. Although nearly all NPHP genes encode ciliary proteins, classifying NPH as a renal ciliopathy, there is evidence for a pathogenic role of a compromised DNA damage response (DDR). Here, we present a novel Nphp7/Glis2-deficient mouse model with an early stop codon using CRISPR/Cas9-mediated genome editing (Glis2Y122X). Homozygous mice displayed dilated kidney tubules progressing to cystic kidney disease with significant fibrosis at a higher age. Interestingly, the kidneys of these animals exhibited an accumulation of DNA damage (DD) early on, even before any functional impairment of the kidneys became apparent. Interactome analysis for GLIS2 revealed an array of DDR-related proteins within the GLIS2 protein complex. Consistent with the in vivo data, the knockdown of Glis2 in kidney epithelial cells led to increased DNA damage. Moreover, supporting the role of GLIS2 in the DDR, we demonstrate that a substantial proportion of GLIS2 is present within the chromatin fraction of cells, which is further increased upon UV-induced DD. Live-cell imaging revealed the rapid recruitment of green fluorescent protein (GFP)-tagged GLIS2 to sites of laser-induced DD, a response diminished in Glis2Y122X and a variant of Glis2 resembling a known patient mutation. Overall, our data provide compelling evidence for the direct involvement of GLIS2 in the DDR, highlighting the loss of genome stability as an important factor contributing to the pathogenesis of renal ciliopathies.NEW & NOTEWORTHY Nephronophthisis (NPH) is a pediatric cystic kidney disease and ciliopathy. We present a novel Glis2/Nphp7-deficient mouse model that shows early accumulation of DNA damage before detectable kidney dysfunction. The GLIS2 protein complex includes DNA damage response factors. GLIS2 localizes to chromatin and rapidly relocates to sites of DNA damage. These findings position GLIS2 as a direct player in genome stability, highlighting impaired DDR as a key contributor to NPH pathogenesis.
proteins
2021-12-28 | Overexpression of smad7 inhibits the TGF-β/Smad signaling pathway and EMT in NPHP1-defective MDCK cells.
Nephronophthisis (NPHP) is a kind of ciliopathy. Interstitial fibrosis occurs at the early stage of the disease. TGF-β/Smad is a key signaling pathway in regulating interstitial fibrosis and epithelial-mesenchymal transition (EMT). In this study, we explored the activation of the TGF-β/Smad signaling pathway and EMT in NPHP1-defective MDCK cells to further understand the pathogenesis of NPHP. NPHP1-knockdown (NPHP1KD) MDCK cells were constructed by recombinant lentiviral short hairpin RNA, and NPHP1-knockout (NPHP1KO) MDCK cells were constructed by using the CRISPR/Cas9 technique. The morphology and migration ability were observed under a microscope. Western blotting was used to detect the expression of E-cadherin, β-catenin, α-smooth muscle actin (α-SMA), fibroblast-specific protein-1(FSP1), TGF-β1, Smad2, Smad3, p-Smad3, Smad4 and Smad7. The localization of Smad3 was determined by immunofluorescence assay. NPHP1KD and NPHP1KO MDCK cells were spindle-shaped and presented EMT-like changes. E-cadherin and β-catenin expression decreased, while α-SMA and FSP1 expression increased; the TGF-β/Smad signaling pathway was activated, Smad2, Smad3, p-Smad3 and Smad4 expression increased, Smad3 translocated to nuclear and Smad7 expression decreased compared with those in wild type MDCK cells. Overexpression of Smad7 reversed these changes to different degrees. Our results indicate that NPHP1 defects induce the activation of the TGF-β/Smad signaling pathway and EMT in MDCK cells. These factors may be implicated in the pathogenesis of interstitial fibrosis in NPHP.
2021-06-22 | Genetic compensation for cilia defects in cep290 mutants by upregulation of cilia-associated small GTPases.
Mutations in CEP290 (also known as NPHP6), a large multidomain coiled coil protein, are associated with multiple cilia-associated syndromes. Over 130 CEP290 mutations have been linked to a wide spectrum of human ciliopathies, raising the question of how mutations in a single gene cause different disease syndromes. In zebrafish, the expressivity of cep290 deficiencies were linked to the type of genetic ablation: acute cep290 morpholino knockdown caused severe cilia-related phenotypes, whereas deficiencies in a CRISPR/Cas9 genetic mutant were restricted to photoreceptor defects. Here, we show that milder phenotypes in genetic mutants were associated with the upregulation of genes encoding the cilia-associated small GTPases arl3, arl13b and unc119b. Upregulation of UNC119b was also observed in urine-derived renal epithelial cells from human Joubert syndrome CEP290 patients. Ectopic expression of arl3, arl13b and unc119b in cep290 morphant zebrafish embryos rescued Kupffer's vesicle cilia and partially rescued photoreceptor outer segment defects. The results suggest that genetic compensation by upregulation of genes involved in a common subcellular process, lipidated protein trafficking to cilia, may be a conserved mechanism contributing to genotype-phenotype variations observed in CEP290 deficiencies. This article has an associated First Person interview with the first author of the paper.
2012-06-01 | The Ciliary Protein Nephrocystin-4 Translocates the Canonical Wnt Regulator Jade-1 to the Nucleus to Negatively Regulate β-Catenin Signaling
Nephronophthisis (NPH) is an autosomal-recessive cystic kidney disease and represents the most common genetic cause for end-stage renal disease in children and adolescents. It can be caused by the mutation of genes encoding for the nephrocystin proteins (NPHPs). All NPHPs localize to primary cilia, classifying this disease as a "ciliopathy." The primary cilium is a critical regulator of several cell signaling pathways. Cystogenesis in the kidney is thought to involve overactivation of canonical Wnt signaling, which is negatively regulated by the primary cilium and several NPH proteins, although the mechanism remains unclear. Jade-1 has recently been identified as a novel ubiquitin ligase targeting the canonical Wnt downstream effector β-catenin for proteasomal degradation. Here, we identify Jade-1 as a novel component of the NPHP protein complex. Jade-1 colocalizes with NPHP1 at the transition zone of primary cilia and interacts with NPHP4. Furthermore, NPHP4 stabilizes protein levels of Jade-1 and promotes the translocation of Jade-1 to the nucleus. Finally, NPHP4 and Jade-1 additively inhibit canonical Wnt signaling, and this genetic interaction is conserved in zebrafish. The stabilization and nuclear translocation of Jade-1 by NPHP4 enhances the ability of Jade-1 to negatively regulate canonical Wnt signaling. Loss of this repressor function in nephronophthisis might be an important factor promoting Wnt activation and contributing to cyst formation.
gene therapies
2024-07-11 | Patient-derived and gene-edited pluripotent stem cells lacking NPHP1 recapitulate juvenile nephronophthisis in abnormalities of primary cilia and renal cyst formation.
Juvenile nephronophthisis is an inherited renal ciliopathy with cystic kidney disease, renal fibrosis, and end-stage renal failure in children and young adults. Mutations in the NPHP1 gene encoding nephrocystin-1 protein have been identified as the most frequently responsible gene and cause the formation of cysts in the renal medulla. The molecular pathogenesis of juvenile nephronophthisis remains elusive, and no effective medicines to prevent end-stage renal failure exist even today. No human cellular models have been available yet. Here, we report a first disease model of juvenile nephronophthisis using patient-derived and gene-edited human induced pluripotent stem cells (hiPSCs) and kidney organoids derived from these hiPSCs. We established NPHP1-overexpressing hiPSCs from patient-derived hiPSCs and NPHP1-deficient hiPSCs from healthy donor hiPSCs. Comparing these series of hiPSCs, we found abnormalities in primary cilia associated with NPHP1 deficiency in hiPSCs. Kidney organoids generated from the hiPSCs lacking NPHP1 formed renal cysts frequently in suspension culture with constant rotation. This cyst formation in patient-derived kidney organoids was rescued by overexpression of NPHP1. Transcriptome analysis on these kidney organoids revealed that loss of NPHP1 caused lower expression of genes related to primary cilia in epithelial cells and higher expression of genes related to the cell cycle. These findings suggested the relationship between abnormality in primary cilia induced by NPHP1 loss and abnormal proliferative characteristics in the formation of renal cysts. These findings demonstrated that hiPSC-based systematic disease modeling of juvenile nephronophthisis contributed to elucidating the molecular pathogenesis and developing new therapies.
2021-08-13 | An Nphp1 knockout mouse model targeting exon 2-20 demonstrates characteristic phenotypes of human nephronophthisis.
Nephronophthisis (NPH) is the most prevalent monogenetic disorder leading to end-stage renal failure (ESRD) in childhood. Mutations in Nphp1, encoding a cilia-localized protein, account for the majority of NPH cases. Despite its identification many years ago, Nphp1 deletions targeting exon 4 or exon 20 have not reproduced the histological features of human NPH in murine models. In this study, we deleted exon 2-20 of Nphp1 by CRISPR/Cas9 gene editing to create a near-total knockout (KO) mouse model (Nphp1del2-20/del2-20). Nphp1del2-20/del2-20 mice faithfully reproduced the renal and extrarenal phenotypes associated with human NPH, including renal cyst development, tubular basement membrane thickening, retinal degeneration and abnormal spermatogenesis. Importantly, Nphp1 re-expression using an adenoviral-associated-virus-9 vector could partially rescue both renal and retinal phenotypes in Nphp1del2-20/del2-20 mice. Our results reported the first relevant Nphp1 mouse model with renal phenotypes for human disease. It will be a valuable model for future studies of Nphp1 function and to develop novel treatments for this common childhood disease.
other
2024-04-22 | The ANKS3/BICC1 protein complex is a master post-transcriptional regulator ofNPHP1ciliopathy-gene transcripts
Abstract Ciliopathies are a class of multi-systemic genetic diseases characterized by ciliary dysfunction. Here, we report a novel ANKS3 variant in patients with a renal ciliopathy known as nephronophthisis (NPH) associated with hepatic defects. ANKS3 is an ankyrin and sterile alpha motif domain-containing protein that interacts with many NPH proteins as well as with BICC1, an RNA-binding protein involved in renal cystic diseases. The pathogenic effect of the ANKS3 mutation was validated in the zebrafish mutant and knock-in rat model, the latter showing urine concentration defect and tubular dilatations similar to NPH patients. In addition, cilia morphology and function as well as epithelialization of kidney tubular cells was affected by loss or mutation of ANKS3 . Finally, our results evidenced that these classically renal ciliopathy-associated phenotypes were linked to the negative regulation of BICC1 by ANKS3 which binds to transcripts of the major NPH gene NPHP1 and mediates their decay through the AGO2-RISC complex and recruitment into P-bodies. Altogether, our findings suggest that the ANKS3/BICC1 complex is a key post-transcriptional regulator of NPHP1 transcript stability, providing another level of regulation of cilium biogenesis and kidney homeostasis, as well as an unusual mechanism leading to NPH-related ciliopathies.
cell therapies
2023-05-24 | A case report of two Chinese monozygotic twins with NPHP1 gene-associated nephronophthisis undergoing kidney transplantation from a related living-donor.
Nephronophthisis (NPHP) is an autosomal recessive cystic kidney disease and the most common hereditary disease leading to end-stage renal disease in children and adolescents. The NPHP1 gene was the first NPHP gene to be discovered. Pathogenic variation of the NPHP1 gene can cause juvenile renal wasting disease type 1. Here, we report the first case of living related kidney transplantation of monozygotic twins with NPHP1 nephronophthisis in China; one of these cases involved cross-blood type kidney transplantation. Our experience shows that patients with NPHP1 nephronophthisis have almost no risk recurrent kidney disease following living related kidney transplantation and genetic testing. The two twins recovered well without any complications. This is the first report of living related kidney transplantation of monozygotic twins with heterozygous deletion of the NPHP1 gene in a Chinese family with NPHP. In addition, genetic testing provides an efficient means of evaluating the safety of living related kidney transplantation in patients with NPHP1 nephronophthisis.
2021-10-13 | Living-Related Kidney Transplantation in a Patient with Juvenile Nephronophthisis.
Nephronophthisis (NPHP) is an autosomal recessive disease manifesting as tubulointerstitial nephritis uniformly progressing to ESRD in approximately 5-10% patients in childhood. Living donor transplantation is the most beneficial mean of renal replacement therapy compared to other methods. However, living kidney donation is contraindicated in potential donor with diseases of autosomal dominant mode of inheritance potentially leading to kidney failure in future. On the other hand, autosomal recessive genetic kidney diseases, such as NPHP, are not usually contraindication to living kidney donation. Herein, we are reporting related living kidney transplantation with a family history of NPHP form 46-year-old mother (heterozygote) to 17-year-old daughter with (autosomal recessive homozygote) with focus on donor follow-up after nephrectomy.
2021-06-21 | Generation of two human induced pluripotent stem cell lines derived from two juvenile nephronophthisis patients with NPHP1 deletion.
Juvenile nephronophthisis is an inherited renal ciliopathy, causing cystic kidney disease, renal fibrosis, and end-stage renal failure. Human induced pluripotent stem cell (hiPSC) lines, derived from two Juvenile nephronophthisis patients, were generated from peripheral blood mononuclear cells by episomal plasmid vectors. Generated hiPSC lines showed self-renewal and pluripotency and carried a large deletion in NPHP1 (Nephrocystin 1) gene. Since the molecular pathogenesis caused by NPHP1 dysfunction remains unclear, these cell resources provide useful tools to establish disease models and to develop new therapies for juvenile nephronophthisis.
2006-11-14 | Persistent post-transplant polyuria managed by bilateral native-kidney laparoscopic nephrectomy.
Polyuria is not considered an absolute indication for pre-transplant nephrectomy; however, it may complicate post-transplantation fluid management. Bilateral native-kidney laparoscopic nephrectomy was performed at our centre in two patients (four kidneys) 1 month after they had received a living related-donor renal transplant. The indication for nephrectomy was severe post-transplant polyuria secondary to the patient's underlying disease: juvenile nephronophthisis. Both patients had a persistent post-transplant daily urine output of 7-8 l/day and continued to have a variable serum creatinine level, dependent on intravenous hydration, more then 3 weeks after transplantation. Bilateral laparoscopic native-kidney nephrectomy in children has previously been reported. However, to the best of our knowledge, laparoscopic nephrectomy has not been described after kidney transplantation and certainly not in the immediate post-transplantation period. The procedure was well tolerated and did not affect renal graft function. In fact, following the procedure, serum creatinine levels stabilized, while daily fluid requirements decreased to 2.5-3.5 l/day in both patients. We concluded that bilateral native-kidney nephrectomy can be safely performed in paediatric renal transplant recipients in the immediate post-transplantation period. This new approach may allow preemptive transplantation and avoid the need for a transition period on dialysis in patients for whom pre-transplant nephrectomy is not absolutely indicated.
1987-08-01 | Renal transplantation in children with oculorenal sydnrome
The association of tapetoretinal degeneration with familial juvenile nephronophthisis is a rare oculorenal syndrome. Without treatment all children die of renal failure prior to adulthood. Information regarding renal transplantation is lacking in these children. This article reflects our experience in two children affected with this syndrome who achieved excellent functional results following living-related kidney transplants. Surgery can be done safely in these children with little or no morbidity. We believe that children with this syndrome benefit from transplantation and that this offers a significant improvement in their quality of life.
small molecules
2026-06-24 | Spatiotemporal dynamics of renal distal convoluted tubule dilatation and cyst formation in nephronophthisis type 1 mice.
Nephronophthisis (NPH), a rare but serious ciliopathy, is the predominant genetic cause of end-stage kidney disease (ESKD) in children and adolescents. Renal tubular dilatation and cyst formation are key pathological features of NPH. The mechanisms underlying renal cystogenesis remain poorly understood. This study employed sex-balanced Nphp1 deletion gene knockout (Nphp1KO) mice at 8, 12, and 24 weeks of age to investigate the spatiotemporal dynamics of renal tubules and cyst development, aiming to identify the origins of renal cysts. Quantitative evaluation of cyst progression revealed a significant increase in cyst number from 8 to 12 weeks of age, but no substantial change from 12 to 24 weeks. Additionally, cyst size remained stable throughout the study period. Serial section tracing and segment-specific tubular marker analysis confirmed that these cysts originated from the distal convoluted tubule (DCT), which displayed segmental dilation while preserving anatomical connections with adjacent, morphologically normal DCT. 3D reconstruction revealed that renal cysts appeared either as a single or in a bead-like arrangement. We demonstrated that human renal cyst epithelial cells from patients with NPH1 also originate primarily from the DCT. This study provides critical experimental evidence of the histopathological features of renal cysts in NPH1, advancing our understanding of the pathogenesis of NPHP-associated tubular dilation and cystogenesis.
2026-05-26 | Developmental switch dichotomizes kidney response to Nphp3 inactivation and treatment outcome
ABSTRACT Nephronophthisis (NPH) is n rare recessive kidney disease caused by biallelic variants in more than 25 NPHP genes encoding proteins that localize to primary cilia. It is characterized by three different forms depending on the age of onset and kidney lesions: infantile (cystic), juvenile/late onset (fibrotic). To date, the pathways linking altered primary cilia function to progressive kidney scarring in NPH remain poorly defined and therapeutic options are lacking. To address these questions, we generated two new mouse NPH models by inactivating Nphp3 specifically in kidney tubules either during embryogenesis or in adult, recapitulating the infantile and juvenile forms of the disease, respectively. Embryonic inactivation produced a rapid and severe cystic phenotype with tubular dedifferentiation, progressive interstitial fibrosis, inflammation and kidney failure, while postnatal inactivation led to a slowly progressive tubulointerstitial nephropathy characterized by tubular atrophy, fibrosis and immune cell infiltration without cyst formation. Strikingly, cilia were preserved in the early stages of both models, indicating that ciliogenesis impairment is not a primary driver of NPH3 pathogenesis. Transcriptomic profiling of the juvenile model revealed that disease initiation is driven by mitochondrial dysfunction, innate immune activation and aberrant cell cycle progression, while epithelial-to-mesenchymal transition and Wnt/β-catenin remodelling emerges only at later stages of disease progression. Therapeutic intervention with the PGE1 (alprostadil) failed to rescue the cystic/infantile model but significantly attenuated fibrosis, inflammation and interstitial fibrosis in the fibrotic/juvenile model. The ability to recapitulate both disease forms through temporal modulation of gene inactivation suggests that primary cilia serve distinct, stage-specific functions in kidney tubular homeostasis, with different cellular processes being selectively vulnerable depending on the causative gene or variant. Collectively, these findings uncover early pathogenic mechanisms that may constitute tractable therapeutic targets for the treatment of nephronophthisis.
2026-03-28 | Renal Tubule-Specific Deletion of Nephrocystin 3 (Nphp3) Causes Infantile Nephronophthisis-like Phenotypes in Mice.
Patients with nephronophthisis caused by nephrocystin 3 (NPHP3) variants rapidly progress to end-stage kidney disease. However, existing Nphp3 mouse models fail to fully recapitulate the characteristics of this disease. We generated a renal tubule-specific Nphp3 knockout mouse model that more accurately mirrors the human disease course. The mouse model was first validated by confirming the loss of Nphp3 protein expression in renal tubules. Comprehensive phenotypic analyses were then performed to assess both renal and extrarenal manifestations. The origin of renal cysts was investigated, and the underlying mechanisms were further validated. We successfully generated a renal tubule-specific Nphp3 knockout mouse model (Cdh16-Cre; Nphp3flox/flox). These mice exhibited a markedly shortened lifespan (5-8 weeks) and developed key features of infantile nephronophthisis, including early-onset renal cysts originating from distal tubules and collecting ducts, progressive interstitial fibrosis that was evident by postnatal week 2, a rapid decline in kidney function, and increased urinary protein levels. Importantly, treatment with the vasopressin V2 receptor antagonist tolvaptan or the mitogen-activated extracellular signal-regulated kinase (MEK) inhibitor 2-(2-chloro-4-iodoanilino)-N-(cyclopropylmethoxy)-3,4-difluorobenzamide (CI-1040) significantly attenuated cyst growth and improved kidney morphology, confirming shared pathogenic pathways with other Nphp3 models. We established a renal tubule-specific Nphp3 knockout mouse model that accurately recapitulates the aggressive infantile form of nephronophthisis characterized by early cystogenesis, progressive fibrosis, and a shortened lifespan, and is ideal for evaluating novel interventions against this currently untreatable ciliopathy.
2025-08-08 | Urinary renal epithelial cells can be used for NPHP1 phenotyping and a personalized therapeutic strategy.
Nephronophthisis (NPHP) is a recessive tubulointerstitial nephropathy and a leading genetic cause of kidney failure in children and young adults. The most common genetic cause is a homozygous deletion of NPHP1, which encodes nephrocystin-1, a protein essential for primary cilium structure and cell junctions. Using personalized medicine and deep phenotyping, we investigated a family with three siblings carrying a homozygous NPHP1 deletion. We compared kidney biopsy tissue and human urine-derived renal epithelial cells (hURECs) from these individuals. Bulk RNA-seq on patient hURECs revealed altered expression in EGFR signalling, extracellular components and adherens junctions, which is consistent with the known roles for nephrocystin-1. Treatment with alprostadil, a proposed NPHP therapy, increased ciliation but worsened ciliary elongation. By contrast, the EGFR kinase inhibitor AG556 rescued of ciliary length and morphology. Transcriptional profiling post-treatment showed AG556 reversed the disease signature more effectively that alprostadil. These findings suggest that EGFR inhibition might offer a more promising therapeutic strategy for NPHP1-associated renal ciliopathy, warranting further testing in in vivo models before clinical application.
2025-07-28 | The nephronophthisis protein GLIS2/NPHP7 is required for the DNA damage response in kidney tubular epithelial cells.
Nephronophthisis (NPH) is an autosomal-recessive cystic kidney disease representing the most frequent genetic cause of end-stage kidney failure in children and adolescents. NPH is caused by genetic variants in >20 NPHP genes. Although nearly all NPHP genes encode ciliary proteins, classifying NPH as a renal ciliopathy, there is evidence for a pathogenic role of a compromised DNA damage response (DDR). Here, we present a novel Nphp7/Glis2-deficient mouse model with an early stop codon using CRISPR/Cas9-mediated genome editing (Glis2Y122X). Homozygous mice displayed dilated kidney tubules progressing to cystic kidney disease with significant fibrosis at a higher age. Interestingly, the kidneys of these animals exhibited an accumulation of DNA damage (DD) early on, even before any functional impairment of the kidneys became apparent. Interactome analysis for GLIS2 revealed an array of DDR-related proteins within the GLIS2 protein complex. Consistent with the in vivo data, the knockdown of Glis2 in kidney epithelial cells led to increased DNA damage. Moreover, supporting the role of GLIS2 in the DDR, we demonstrate that a substantial proportion of GLIS2 is present within the chromatin fraction of cells, which is further increased upon UV-induced DD. Live-cell imaging revealed the rapid recruitment of green fluorescent protein (GFP)-tagged GLIS2 to sites of laser-induced DD, a response diminished in Glis2Y122X and a variant of Glis2 resembling a known patient mutation. Overall, our data provide compelling evidence for the direct involvement of GLIS2 in the DDR, highlighting the loss of genome stability as an important factor contributing to the pathogenesis of renal ciliopathies.NEW & NOTEWORTHY Nephronophthisis (NPH) is a pediatric cystic kidney disease and ciliopathy. We present a novel Glis2/Nphp7-deficient mouse model that shows early accumulation of DNA damage before detectable kidney dysfunction. The GLIS2 protein complex includes DNA damage response factors. GLIS2 localizes to chromatin and rapidly relocates to sites of DNA damage. These findings position GLIS2 as a direct player in genome stability, highlighting impaired DDR as a key contributor to NPH pathogenesis.
proteins
2021-12-28 | Overexpression of smad7 inhibits the TGF-β/Smad signaling pathway and EMT in NPHP1-defective MDCK cells.
Nephronophthisis (NPHP) is a kind of ciliopathy. Interstitial fibrosis occurs at the early stage of the disease. TGF-β/Smad is a key signaling pathway in regulating interstitial fibrosis and epithelial-mesenchymal transition (EMT). In this study, we explored the activation of the TGF-β/Smad signaling pathway and EMT in NPHP1-defective MDCK cells to further understand the pathogenesis of NPHP. NPHP1-knockdown (NPHP1KD) MDCK cells were constructed by recombinant lentiviral short hairpin RNA, and NPHP1-knockout (NPHP1KO) MDCK cells were constructed by using the CRISPR/Cas9 technique. The morphology and migration ability were observed under a microscope. Western blotting was used to detect the expression of E-cadherin, β-catenin, α-smooth muscle actin (α-SMA), fibroblast-specific protein-1(FSP1), TGF-β1, Smad2, Smad3, p-Smad3, Smad4 and Smad7. The localization of Smad3 was determined by immunofluorescence assay. NPHP1KD and NPHP1KO MDCK cells were spindle-shaped and presented EMT-like changes. E-cadherin and β-catenin expression decreased, while α-SMA and FSP1 expression increased; the TGF-β/Smad signaling pathway was activated, Smad2, Smad3, p-Smad3 and Smad4 expression increased, Smad3 translocated to nuclear and Smad7 expression decreased compared with those in wild type MDCK cells. Overexpression of Smad7 reversed these changes to different degrees. Our results indicate that NPHP1 defects induce the activation of the TGF-β/Smad signaling pathway and EMT in MDCK cells. These factors may be implicated in the pathogenesis of interstitial fibrosis in NPHP.
2021-06-22 | Genetic compensation for cilia defects in cep290 mutants by upregulation of cilia-associated small GTPases.
Mutations in CEP290 (also known as NPHP6), a large multidomain coiled coil protein, are associated with multiple cilia-associated syndromes. Over 130 CEP290 mutations have been linked to a wide spectrum of human ciliopathies, raising the question of how mutations in a single gene cause different disease syndromes. In zebrafish, the expressivity of cep290 deficiencies were linked to the type of genetic ablation: acute cep290 morpholino knockdown caused severe cilia-related phenotypes, whereas deficiencies in a CRISPR/Cas9 genetic mutant were restricted to photoreceptor defects. Here, we show that milder phenotypes in genetic mutants were associated with the upregulation of genes encoding the cilia-associated small GTPases arl3, arl13b and unc119b. Upregulation of UNC119b was also observed in urine-derived renal epithelial cells from human Joubert syndrome CEP290 patients. Ectopic expression of arl3, arl13b and unc119b in cep290 morphant zebrafish embryos rescued Kupffer's vesicle cilia and partially rescued photoreceptor outer segment defects. The results suggest that genetic compensation by upregulation of genes involved in a common subcellular process, lipidated protein trafficking to cilia, may be a conserved mechanism contributing to genotype-phenotype variations observed in CEP290 deficiencies. This article has an associated First Person interview with the first author of the paper.
2012-06-01 | The Ciliary Protein Nephrocystin-4 Translocates the Canonical Wnt Regulator Jade-1 to the Nucleus to Negatively Regulate β-Catenin Signaling
Nephronophthisis (NPH) is an autosomal-recessive cystic kidney disease and represents the most common genetic cause for end-stage renal disease in children and adolescents. It can be caused by the mutation of genes encoding for the nephrocystin proteins (NPHPs). All NPHPs localize to primary cilia, classifying this disease as a "ciliopathy." The primary cilium is a critical regulator of several cell signaling pathways. Cystogenesis in the kidney is thought to involve overactivation of canonical Wnt signaling, which is negatively regulated by the primary cilium and several NPH proteins, although the mechanism remains unclear. Jade-1 has recently been identified as a novel ubiquitin ligase targeting the canonical Wnt downstream effector β-catenin for proteasomal degradation. Here, we identify Jade-1 as a novel component of the NPHP protein complex. Jade-1 colocalizes with NPHP1 at the transition zone of primary cilia and interacts with NPHP4. Furthermore, NPHP4 stabilizes protein levels of Jade-1 and promotes the translocation of Jade-1 to the nucleus. Finally, NPHP4 and Jade-1 additively inhibit canonical Wnt signaling, and this genetic interaction is conserved in zebrafish. The stabilization and nuclear translocation of Jade-1 by NPHP4 enhances the ability of Jade-1 to negatively regulate canonical Wnt signaling. Loss of this repressor function in nephronophthisis might be an important factor promoting Wnt activation and contributing to cyst formation.
gene therapies
2024-07-11 | Patient-derived and gene-edited pluripotent stem cells lacking NPHP1 recapitulate juvenile nephronophthisis in abnormalities of primary cilia and renal cyst formation.
Juvenile nephronophthisis is an inherited renal ciliopathy with cystic kidney disease, renal fibrosis, and end-stage renal failure in children and young adults. Mutations in the NPHP1 gene encoding nephrocystin-1 protein have been identified as the most frequently responsible gene and cause the formation of cysts in the renal medulla. The molecular pathogenesis of juvenile nephronophthisis remains elusive, and no effective medicines to prevent end-stage renal failure exist even today. No human cellular models have been available yet. Here, we report a first disease model of juvenile nephronophthisis using patient-derived and gene-edited human induced pluripotent stem cells (hiPSCs) and kidney organoids derived from these hiPSCs. We established NPHP1-overexpressing hiPSCs from patient-derived hiPSCs and NPHP1-deficient hiPSCs from healthy donor hiPSCs. Comparing these series of hiPSCs, we found abnormalities in primary cilia associated with NPHP1 deficiency in hiPSCs. Kidney organoids generated from the hiPSCs lacking NPHP1 formed renal cysts frequently in suspension culture with constant rotation. This cyst formation in patient-derived kidney organoids was rescued by overexpression of NPHP1. Transcriptome analysis on these kidney organoids revealed that loss of NPHP1 caused lower expression of genes related to primary cilia in epithelial cells and higher expression of genes related to the cell cycle. These findings suggested the relationship between abnormality in primary cilia induced by NPHP1 loss and abnormal proliferative characteristics in the formation of renal cysts. These findings demonstrated that hiPSC-based systematic disease modeling of juvenile nephronophthisis contributed to elucidating the molecular pathogenesis and developing new therapies.
2021-08-13 | An Nphp1 knockout mouse model targeting exon 2-20 demonstrates characteristic phenotypes of human nephronophthisis.
Nephronophthisis (NPH) is the most prevalent monogenetic disorder leading to end-stage renal failure (ESRD) in childhood. Mutations in Nphp1, encoding a cilia-localized protein, account for the majority of NPH cases. Despite its identification many years ago, Nphp1 deletions targeting exon 4 or exon 20 have not reproduced the histological features of human NPH in murine models. In this study, we deleted exon 2-20 of Nphp1 by CRISPR/Cas9 gene editing to create a near-total knockout (KO) mouse model (Nphp1del2-20/del2-20). Nphp1del2-20/del2-20 mice faithfully reproduced the renal and extrarenal phenotypes associated with human NPH, including renal cyst development, tubular basement membrane thickening, retinal degeneration and abnormal spermatogenesis. Importantly, Nphp1 re-expression using an adenoviral-associated-virus-9 vector could partially rescue both renal and retinal phenotypes in Nphp1del2-20/del2-20 mice. Our results reported the first relevant Nphp1 mouse model with renal phenotypes for human disease. It will be a valuable model for future studies of Nphp1 function and to develop novel treatments for this common childhood disease.
other
2024-04-22 | The ANKS3/BICC1 protein complex is a master post-transcriptional regulator ofNPHP1ciliopathy-gene transcripts
Abstract Ciliopathies are a class of multi-systemic genetic diseases characterized by ciliary dysfunction. Here, we report a novel ANKS3 variant in patients with a renal ciliopathy known as nephronophthisis (NPH) associated with hepatic defects. ANKS3 is an ankyrin and sterile alpha motif domain-containing protein that interacts with many NPH proteins as well as with BICC1, an RNA-binding protein involved in renal cystic diseases. The pathogenic effect of the ANKS3 mutation was validated in the zebrafish mutant and knock-in rat model, the latter showing urine concentration defect and tubular dilatations similar to NPH patients. In addition, cilia morphology and function as well as epithelialization of kidney tubular cells was affected by loss or mutation of ANKS3 . Finally, our results evidenced that these classically renal ciliopathy-associated phenotypes were linked to the negative regulation of BICC1 by ANKS3 which binds to transcripts of the major NPH gene NPHP1 and mediates their decay through the AGO2-RISC complex and recruitment into P-bodies. Altogether, our findings suggest that the ANKS3/BICC1 complex is a key post-transcriptional regulator of NPHP1 transcript stability, providing another level of regulation of cilium biogenesis and kidney homeostasis, as well as an unusual mechanism leading to NPH-related ciliopathies.
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