Nephronophthisis (NPHP) is the most prevalent monogenic disease leading to end-stage renal failure in childhood. RhoA activation is involved in NPHP pathogenesis. This study explored the role of the ...RhoA activator guanine nucleotide exchange factor (GEF)-H1 in NPHP pathogenesis. We analyzed the expression and distribution of GEF-H1 in
knockout (
) mice using Western blotting and immunofluorescence, followed by GEF-H1 knockdown. Immunofluorescence and renal histology were used to examine the cysts, inflammation, and fibrosis. A RhoA GTPase activation assay and Western blotting were used to detect the expression of downstream GTP-RhoA and p-MLC2, respectively. In
knockdown (
) human kidney proximal tubular cells (HK2 cells), we detected the expressions of E-cadherin and α-smooth muscle actin (α-SMA). In vivo, increased expression and redistribution of GEF-H1, and higher levels of GTP-RhoA and p-MLC2 in renal tissue of
mice were observed, together with renal cysts, fibrosis, and inflammation. These changes were alleviated by GEF-H1 knockdown. In vitro, the expression of GEF-H1 and activation of RhoA were also increased, with increased expression of α-SMA and decreased E-cadherin. GEF-H1 knockdown reversed these changes in
HK2 cells. Thus, the GEF-H1/RhoA/MLC2 axis is activated in
defects and may play a pivotal role in NPHP pathogenesis.
Abstract
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.
Coenzyme Q10 (CoQ10) is involved in the biosynthesis of adenosine triphosphate (ATP), and is most abundant in the mitochondrial membrane. The primary CoQ10 deficiency caused by
defect is mostly ...manifested as encephalopathy, encephalopathy with nephropathy, and rarely as an isolated nephrotic syndrome.
Clinical and pathological data and peripheral blood samples of 2 siblings with steroid-resistant nephrotic syndrome (SRNS) and their family members of a Chinese pedigree were collected. DNA was extracted and subjected to next-generation sequencing of target genes of hereditary nephropathy.
Compound heterozygous mutations of
(c.1058A > G, p.Y353C, paternal and c.973A > G, p.T325A, maternal)were identified in both siblings of the pedigree. Mutation of p.Y353C was novel. The proband was a girl, who presented with SRNS at the age of 7 months. CoQ10 was administered after the gene sequencing results came out. Proteinuria decreased gradually to 1+, occasionally negative. The child was normal in growth and intelligence. She is now 4 years old. The second patient was her elder brother. He was found to have SRNS at the age of 2 years old. Renal pathology indicated focal segmental glomerulosclerosis (FSGS). Electronic microcopy revealed that a large quantity of mitochondria with normal contour was accumulated within the podocytes. Both patients were in normal intelligence without convulsion.
The 2 cases harboring
compound heterozygous mutations presented with isolated SRNS, with a renal pathology of FSGS and a large quantity of mitochondria with normal contour accumulated within the podocytes. CoQ10 was efficacy in eliminating proteinuria.
To explore the genetic basis for a child presented with renal failure and multi-cystic dysplastic kidney without anal atresia.
Peripheral blood sample of the child and his parents were collected and ...subjected to whole exome sequencing. Candidate variant was verified by Sanger sequencing.
The 40-day-old infant had presented with vomiting brown matter in a 7 days neonate and was transferred for kidney failure. Clinical examination has discovered renal failure, polycystic renal dysplasia, congenital hypothyroidism, bilateral thumb polydactyly, sensorineural hearing loss and preauricular dermatophyte. Genetic testing revealed that he has harbored a previously unreported c.824delT, p.L275Yfs*10 frameshift variant of SALL1 gene, which was confirmed by Sanger sequencing as de novo.
The patient was diagnosed with Townes-Brocks syndrome due to the novel de novo variant of SALL1 gene. Townes-Brocks syndrome without anal atresia is rare. Above finding has also enriched the mutational spectrum of the SALL1 gene.
Background:
Nephronophthisis (NPH) is the most common genetic cause of end-stage renal disease (ESRD) in childhood, and
NPHP1
is the major pathogenic gene. Cyst formation at the corticomedullary ...junction is a pathological feature of NPH, but the mechanism underlying cystogenesis is not well understood. The isolation and identification of cystic cell subpopulation could help to identify their origins and provide vital clues to the mechanisms underlying cystogenesis in NPH.
Methods:
Single-nucleus RNA sequencing (snRNA-seq) was performed to produce an atlas of NPHP1 renal cells. Kidney samples were collected from WT (
Nphp1
+/+
) mice and NPHP1 (
Nphp1
del2-20/del2-20
) model mice.
Results:
A comprehensive atlas of the renal cellular landscape in NPHP1 was generated, consisting of 14 basic renal cell types as well as a subpopulation of DCT cells that was overrepresented in NPHP1 kidneys compared to WT kidneys. GO analysis revealed significant downregulation of genes associated with tubular development and kidney morphogenesis in this subpopulation. Furthermore, the reconstruction of differentiation trajectories of individual cells within this subpopulation confirmed that a specific group of cells in
NPHP1
mice become arrested at an early stage of differentiation and proliferate to form cysts. We demonstrate that
Niban1
is a specific molecular marker of cystic cells in both mice and human NPHP1.
Conclusion:
In summary, we report a novel subpopulation of DCT cells, marked by
Niban1,
that are classified as cystic cells in the NPHP1 mice kidney. These results offer fresh insights into the cellular and molecular basis of cystogenesis in NPH.
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.
•NPHP1 defects induce the activation of the TGF-β/Smad signaling pathway.•NPHP1 defects induce EMT in MDCK cells.•TGF-β/Smad signaling may be related with the pathogenesis of interstitial fibrosis in NPHP.
To compare the effects of different approaches to establishing rat models of acute liver failure (ALF).
Sixty-eight Sprague-Dawley rats were randomly divided into 3 groups for establishing ALF models ...using 3 different approaches, namely conventional hepatectomy for resecting 90% liver tissue as described by Higgins and Anderson, modified bloodless hepatectomy for resecting 90% liver tissue, and intraperitoneal injections of 700 mg/kg D-galactosamine (D-gal) and 5 µg/kg lipopolysaccharide (LPS). The mortality of the rats due to postoperative bleeding and survival rate at 7 days after the surgery were recorded. The levels of alanine aminotransferase (ALT), total bilimbin (Tbil), albumin (ALB), NH3, glucose (Glu) and prothrombin time (PT) were monitored, and histopathologies of the liver were examined at 24 and 72 h after the surgery.
The mortality rate due to postoperative bleeding was higher in conventional hepatectomy group than in the modified surgical group (15% vs 0). The survival rate at 7 days was 25%, 0
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The DGKE gene encodes the diacylglycerol kinase epsilon (DGKε). Loss-of-function mutations of DGKE caused a group of rare renal diseases, which are called DGKE nephropathy. We report ...the clinical manifestations and therapeutic effects of a patient diagnosed with DGKE nephropathy.
The patient’s initial symptoms were fever, diarrhea, eyelid edema, acute anemia, acute thrombocytopenia, an elevation of plasm D-dimer, proteinuria, microscopic hematuria, without oliguria or renal insufficiency at the age of 7.6 months. Hemolytic uremic syndrome was diagnosed. His proteinuria and hematuria turned out negative 2 months later. Proteinuria was noticed again at the age of 5.5-year old when he was brought to the hospital because of failure to thrive. Since then, he had been noticed with persistent proteinuria.
Genetic analysis revealed 2 novel heterozygous mutations on DGKE of the patient. Renal pathology mimicked membrane proliferative glomerulonephritis (MPGN).
After a 5-month treatment of cyclosporine A (CsA), proteinuria and hypoproteinemia have relieved apparently. We also observed an improvement of his growth.
Nephronophthisis (NPHP) is the most common genetic cause of end-stage renal disease (ESRD) in children. This study was performed to explore the pathogenic gene mutations and clinical and pathological ...features of Chinese patients with NPHP.
Patients for whom causative mutations were not identified in our previous study, as well as those recruited later, were subjected to whole-exome next-generation sequencing (NGS) or the exome of 63 primary cilia disease genes.
We recruited 55 patients (27 boys and 28 girls) from 48 families, mainly from South China. We subjected 35 patients to NGS. Disease-causing mutations were revealed in seven more families (nine patients) by NGS. In total, disease-causing mutations were identified in 25 patients from 19 families, accounting for 39.6% (19/48) of all families, and novel mutation rate was 77.8% (35/45). NPHP1 and NPHP3 mutations were identified in 14.6% (7/48) and 12.5% (6/48) of all families, respectively. The patient with CEP83 mutations presented with prominent glomerular cysts and glomeruli dysplasia without extrarenal involvement.
A high novel mutation rate was identified, and disease-causing mutations of NPHP3 prevailed in this group of Chinese NPHP patients. This is the second report of a patient with CEP83 mutations.
Purpose
The objective of this study was to evaluate the effectiveness of BPTB autografts versus HT autografts at a minimum of 5 years after anterior cruciate ligament (ACL) reconstruction.
Methods
A ...systematical search of literature was performed in PubMed, Embase and the Cochrane library to identify published randomized controlled trials (RCT) or prospective cohort studies (PCS) relevant to ACL reconstruction comparing BPTB and HT autografts. The results of the eligible studies were analysed in terms of objective International Knee Documentation Committee (IKDC) scores, return to preinjury activity level, KT-1000, Lachman test, pivot shift test, anterior knee pain, kneeling pain, extension loss, and flexion loss, graft failure and radiographic outcomes. Study quality was assessed by using the Coleman methodology score for included studies. Two reviewers independently assessed each study for quality and extracted data. Subgroup analysis of the primary outcomes was conducted according to the type of study design (RCT or PCS).
Results
Twelve RCTs, two PCS including 1,443 patients comparing hamstring and patellar tendon autografts were identified. The results of the meta-analysis showed that there were no significant differences between BPTB and HT in terms of objective IKDC score (
P
= 0.83), return to preinjury activity (
P
= 0.69), KT-1000 (
P
= 0.12), Lachman test (
P
= 0.76), pivot shift test (
P
= 0.11), extension deficit (
P
= 0.09), flexion deficit (
P
= 0.71) and graft failure (
P
= 0.22). However, outcomes in favour of HT autografts were found in terms of anterior knee pain (
P
= 0.0001) and kneeling pain (
P
= 0.001). Radiographic evidence of osteoarthritis (OA) showed that incidence of OA was significantly higher in BPTB groups compared with HT groups based on IKDC system. These findings were still robust during the sensitivity analysis. Results from subgroup analysis of the primary outcomes were consistent with the overall analysis.
Conclusion
Meta-analysis of prospective trials did not detect any significant differences in clinical results, as evidenced by the objective IKDC score, return to preinjury activity level, KT-1000, Lachman test, pivot shift test, extension loss, flexion loss and graft failure. However, the meta-analysis revealed that ACL reconstruction with BPTB autografts resulted in increased anterior knee pain and kneeling pain compared with hamstring autografts. Increased incidence of OA was found after ACL reconstruction at a minimum of 5 years in BPTB group compared with HT autografts. This result should be cautiously interpreted. More high-quality RCT with strictly specified inclusion criteria are highly required before drawing a reliable conclusion.
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