Project description:Alport syndrome (AS) is a rare disease characterized by defective glomerular basement membranes, caused by mutations in COL4A3, COL4A4 and COL4A5, which synthesize collagen type IV. Patients present with progressive proteinuria, hematuria and podocyte loss. There is currently no cure for AS, and this is mainly due to its complex and variable pathogenesis, as well as the lack of models that can faithfully mimic the human phenotype.
Project description:Alport syndrome (AS) is a hereditary glomerulonephritis caused by COL4A3, COL4A4 or COL4A5 gene mutations and characterized by abnormalities of glomerular basement membranes (GBMs). Due to a lack of curative treatments, the condition proceeds to end-stage renal disease even in adolescents. Hampering drug discovery is the absence of effective in vitro methods for testing the restoration of normal GBMs. Here, we aimed to develop kidney organoid models from AS patient iPSCs for this purpose. We established iPSC-derived collagen α5(IV)-expressing kidney organoids and confirmed that kidney organoids from COL4A5 mutation-corrected iPSCs restore collagen α5(IV) protein expression. Importantly, our model recapitulates the differences in collagen composition between iPSC-derived kidney organoids from mild and severe AS cases. Furthermore, we demonstrate that a chemical chaperone, 4-phenyl butyric acid, has the potential to correct GBM abnormalities in kidney organoids showing mild AS phenotypes. This iPSC-derived kidney organoid model will contribute to drug discovery for AS.
Project description:Purpose: MicroRNA-21 contributes to the pathogenesis of fibrogenic diseases in multiple organs including the kidney. To evaluate the therapeutic utility of antimiR-21 oligonucleotides in chronic kidney disease, we silenced miR-21 in mice that develop Alport Nephropathy due to a defect in the Col4a3 gene. The goals of this study to assess the effect of inhibiting miR-21 in the Col4a3-/- Alport Syndrome mouse model at 9 weeks of age. Methods: Col4a3-/-, Col4a3+/-, and Col4a3+/+ mice in the 129X1/SvJ genetic background were obtained. Mice received anti–miR-21 (25 mg/kg) or control anti-miR (25mg/kg) in phosphate-buffered saline (PBS) by inter-scapular subcutaneous injection twice per week. In some experiments mice received a range of doses from 12.5mg/kg once a week to 50mg/kg once a week. Anti–miR-21 is a high-affinity oligonucleotide complementary to the active site of miR-21. Mice received injections starting at 24 days (3.5 weeks) after birth and ending at 5, 7, 9 or 16 weeks after birth depending on the study objectives. Total RNA from kidney tissue was extracted as per manufacturer’s instructions (miREASY kit, Qiagen). RNA quality was assessed using BioAnalyzer (Agilent). mRNA expression profiles were determined using next-generation sequencing (NGS) on the Illumina HiSeq 2000 platform producing 50bp paired-end reads. Bowtie/TopHat suites were used to align the reads to mouse genome or transcriptome and RSEM were used to quantify gene abundances. Gene level counts were then normalized with the R/Bioconductor package limma using the voom/variance stabilization method. Results: Anti-miR-21 enhanced PPAR?/RXR activity and associated downstream signaling pathways in glomerular, tubular and interstitial cells, enhanced mitochondrial function, which reduced mitochondrial ROS production and preserved tubular cell functions. In addition, inhibition of miR-21 reduced fibrogenic and inflammatory signaling in glomerular and interstitial cells, likely as a consequence of enhanced PPAR?/RXR activity and mitochondrial function. Inhibition of miR-21 represents a novel therapeutic strategy for chronic kidney diseases including Alport Nephropathy. Whole kidney mRNA profiles of wild type and Col4a3-/- mice treated with either PBS or antimiR-21, ending at 9 weeks of age, were generated by Next Generation Sequencing in triplicate using Illumina HiSeq 2000
Project description:Purpose: MicroRNA-21 contributes to the pathogenesis of fibrogenic diseases in multiple organs including the kidney. To evaluate the therapeutic utility of antimiR-21 oligonucleotides in chronic kidney disease, we silenced miR-21 in mice that develop Alport Nephropathy due to a defect in the Col4a3 gene. The goals of this study to assess the effect of inhibiting miR-21 in the Col4a3-/- Alport Syndrome mouse model at 5.5 weeks of age. Methods: Col4a3-/-, Col4a3+/-, and Col4a3+/+ mice in the 129X1/SvJ genetic background were obtained. Mice received anti–miR-21 (25 mg/kg) or control anti-miR (25mg/kg) in phosphate-buffered saline (PBS) by inter-scapular subcutaneous injection twice per week. In some experiments mice received a range of doses from 12.5mg/kg once a week to 50mg/kg once a week. Anti–miR-21 is a high-affinity oligonucleotide complementary to the active site of miR-21. Mice received injections starting at 24 days (3.5 weeks) after birth and ending at 5, 7, 9 or 16 weeks after birth depending on the study objectives. Total RNA from kidney tissue was extracted as per manufacturerâs instructions (miREASY kit, Qiagen). RNA quality was assessed using BioAnalyzer (Agilent). mRNA expression profiles were determined using next-generation sequencing (NGS) on the Illumina HiSeq 2000 platform producing 50bp paired-end reads. Bowtie/TopHat suites were used to align the reads to mouse genome or transcriptome and RSEM were used to quantify gene abundances. Gene level counts were then normalized with the R/Bioconductor package limma using the voom/variance stabilization method. Results: Anti-miR-21 enhanced PPARα/RXR activity and associated downstream signaling pathways in glomerular, tubular and interstitial cells, enhanced mitochondrial function, which reduced mitochondrial ROS production and preserved tubular cell functions. In addition, inhibition of miR-21 reduced fibrogenic and inflammatory signaling in glomerular and interstitial cells, likely as a consequence of enhanced PPARα/RXR activity and mitochondrial function. Inhibition of miR-21 represents a novel therapeutic strategy for chronic kidney diseases including Alport Nephropathy. Whole kidney mRNA profiles of Col4a3+/- (triplicate) and Col4a3-/- (quadruplicates) mice treated with either PBS or antimiR-21, ending at 5.5 weeks of age, were generated by Next Generation Sequencing using Illumina HiSeq 2000
Project description:Alport syndrome, a type IV collagen disorder, leads to glomerular disease and, in some patients, hearing loss. AS is treated with inhibitors of the renin-angiotensin system; however, a need exists for novel therapies, especially those addressing both major pathologies. Sparsentan is a single-molecule dual endothelin type-A and angiotensin II type 1 receptor antagonist (DEARA) under clinical development for focal segmental glomerulosclerosis and IgA nephropathy. We report the ability of sparsentan to ameliorate both renal and inner ear pathologies in an autosomal-recessive Alport mouse model. Sparsentan significantly delayed onset of glomerulosclerosis, interstitial fibrosis, proteinuria, and glomerular filtration rate decline. Sparsentan attenuated glomerular basement membrane defects, blunted mesangial filopodial invasion into the glomerular capillaries, increased lifespan more than losartan, and lessened changes in profibrotic/proinflammatory genes pathways in both the glomerular and renal cortical compartments. Notably, treatment with sparsentan, but not losartan, prevented accumulation of extracellular matrix in the strial capillary basement membranes in the inner ear and reduced susceptibility to hearing loss. Improvements in lifespan and in renal and strial pathology were observed even when sparsentan was initiated after development of renal pathologies. These findings suggest that sparsentan may address both renal and hearing pathologies in Alport syndrome patients.
Project description:Large Xq22.3 deletion in Czech family inherited from unaffaceted mother leading to manifestation of X-linked contiguous gene deletion syndrome known as Alport syndrome with intellectual disability (ATS-ID) or AMME complex (OMIM #300194)
Project description:Purpose: MicroRNA-21 contributes to the pathogenesis of fibrogenic diseases in multiple organs including the kidney. To evaluate the therapeutic utility of antimiR-21 oligonucleotides in chronic kidney disease, we silenced miR-21 in mice that develop Alport Nephropathy due to a defect in the Col4a3 gene. The goals of this study to assess the effect of inhibiting miR-21 in the Col4a3-/- Alport Syndrome mouse model at 5.5 weeks of age. Methods: Col4a3-/-, Col4a3+/-, and Col4a3+/+ mice in the 129X1/SvJ genetic background were obtained. Mice received anti–miR-21 (25 mg/kg) or control anti-miR (25mg/kg) in phosphate-buffered saline (PBS) by inter-scapular subcutaneous injection twice per week. In some experiments mice received a range of doses from 12.5mg/kg once a week to 50mg/kg once a week. Anti–miR-21 is a high-affinity oligonucleotide complementary to the active site of miR-21. Mice received injections starting at 24 days (3.5 weeks) after birth and ending at 5, 7, 9 or 16 weeks after birth depending on the study objectives. Total RNA from kidney tissue was extracted as per manufacturer’s instructions (miREASY kit, Qiagen). RNA quality was assessed using BioAnalyzer (Agilent). mRNA expression profiles were determined using next-generation sequencing (NGS) on the Illumina HiSeq 2000 platform producing 50bp paired-end reads. Bowtie/TopHat suites were used to align the reads to mouse genome or transcriptome and RSEM were used to quantify gene abundances. Gene level counts were then normalized with the R/Bioconductor package limma using the voom/variance stabilization method. Results: Anti-miR-21 enhanced PPARα/RXR activity and associated downstream signaling pathways in glomerular, tubular and interstitial cells, enhanced mitochondrial function, which reduced mitochondrial ROS production and preserved tubular cell functions. In addition, inhibition of miR-21 reduced fibrogenic and inflammatory signaling in glomerular and interstitial cells, likely as a consequence of enhanced PPARα/RXR activity and mitochondrial function. Inhibition of miR-21 represents a novel therapeutic strategy for chronic kidney diseases including Alport Nephropathy.