RESUMO
Acid sphingomyelinase (ASM) has been reported to increase tissue ceramide and thereby mediate hyperhomocysteinemia (hHcy)-induced glomerular nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasome activation, inflammation, and sclerosis. In the present study, we tested whether somatic podocyte-specific silencing of Smpd1 gene (mouse ASM gene code) attenuates hHcy-induced NLRP3 inflammasome activation and associated extracellular vesicle (EV) release in podocytes and thereby suppresses glomerular inflammatory response and injury. In vivo, somatic podocyte-specific Smpd1 gene silencing almost blocked hHcy-induced glomerular NLRP3 inflammasome activation in Podocre (podocyte-specific expression of cre recombinase) mice compared with control littermates. By nanoparticle tracking analysis (NTA), floxed Smpd1 shRNA transfection was found to abrogate hHcy-induced elevation of urinary EV excretion in Podocre mice. In addition, Smpd1 gene silencing in podocytes prevented hHcy-induced immune cell infiltration into glomeruli, proteinuria, and glomerular sclerosis in Podocre mice. Such protective effects of podocyte-specific Smpd1 gene silencing were mimicked by global knockout of Smpd1 gene in Smpd1-/- mice. On the contrary, podocyte-specific Smpd1 gene overexpression exaggerated hHcy-induced glomerular pathological changes in Smpd1trg/Podocre (podocyte-specific Smpd1 gene overexpression) mice, which were significantly attenuated by transfection of floxed Smpd1 shRNA. In cell studies, we also confirmed that Smpd1 gene knockout or silencing prevented homocysteine (Hcy)-induced elevation of EV release in the primary cultures of podocyte isolated from Smpd1-/- mice or podocytes of Podocre mice transfected with floxed Smpd1 shRNA compared with WT/WT podocytes. Smpd1 gene overexpression amplified Hcy-induced EV secretion from podocytes of Smpd1trg/Podocre mice, which was remarkably attenuated by transfection of floxed Smpd1 shRNA. Mechanistically, Hcy-induced elevation of EV release from podocytes was blocked by ASM inhibitor (amitriptyline, AMI), but not by NLRP3 inflammasome inhibitors (MCC950 and glycyrrhizin, GLY). Super-resolution microscopy also showed that ASM inhibitor, but not NLRP3 inflammasome inhibitors, prevented the inhibition of lysosome-multivesicular body interaction by Hcy in podocytes. Moreover, we found that podocyte-derived inflammatory EVs (released from podocytes treated with Hcy) induced podocyte injury, which was exaggerated by T cell coculture. Interstitial infusion of inflammatory EVs into renal cortex induced glomerular injury and immune cell infiltration. In conclusion, our findings suggest that ASM in podocytes plays a crucial role in the control of NLRP3 inflammasome activation and inflammatory EV release during hHcy and that the development of podocyte-specific ASM inhibition or Smpd1 gene silencing may be a novel therapeutic strategy for treatment of hHcy-induced glomerular disease with minimized side effect.NEW & NOTEWORTHY In the present study, we tested whether podocyte-specific silencing of Smpd1 gene attenuates hyperhomocysteinemia (hHcy)-induced nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasome activation and associated inflammatory extracellular vesicle (EV) release in podocytes and thereby suppresses glomerular inflammatory response and injury. Our findings suggest that acid sphingomyelinase (ASM) in podocytes plays a crucial role in the control of NLRP3 inflammasome activation and inflammatory EV release during hHcy. Based on our findings, it is anticipated that the development of podocyte-specific ASM inhibition or Smpd1 gene silencing may be a novel therapeutic strategy for treatment of hHcy-induced glomerular disease with minimized side effects.
Assuntos
Hiper-Homocisteinemia , Inflamassomos , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR , Podócitos , Esfingomielina Fosfodiesterase , Animais , Esfingomielina Fosfodiesterase/genética , Esfingomielina Fosfodiesterase/metabolismo , Podócitos/metabolismo , Podócitos/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Hiper-Homocisteinemia/metabolismo , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/genética , Inflamassomos/metabolismo , Inflamassomos/genética , Glomérulos Renais/patologia , Glomérulos Renais/metabolismo , Glomerulonefrite/patologia , Glomerulonefrite/metabolismo , Glomerulonefrite/genética , Inativação Gênica , Camundongos , Camundongos Endogâmicos C57BL , Vesículas Extracelulares/metabolismo , Masculino , Modelos Animais de DoençasRESUMO
Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a systemic autoimmune disease pathologically characterized by vascular necrosis with inflammation. During AAV development, activated neutrophils produce reactive oxygen species (ROS), leading to the aberrant formation of neutrophil extracellular traps (NETs) via NETosis and subsequent fibrinoid vascular necrosis. Nuclear factor-erythroid 2-related factor 2 (Nrf2) functions as an intracellular defense system to counteract oxidative stress by providing antioxidant properties. Herein, we explored the role of Nrf2 in the pathogenesis of AAV. The role and mechanism of Nrf2 in ANCA-stimulated neutrophils and subsequent endothelial injury were evaluated in vitro using Nrf2 genetic deletion and Nrf2 activator treatment. In corresponding in vivo studies, the role of Nrf2 in ANCA-transfer AAV and spontaneous AAV murine models was examined. Pharmacological activation of Nrf2 in vitro suppressed ANCA-induced NET formation via the inhibition of ROS. In contrast, NET formation was enhanced in Nrf2-deficient neutrophils. Furthermore, Nrf2 activation protected endothelial cells from ANC-induced NETs-mediated injury. In vivo, Nrf2 activation ameliorated glomerulonephritis in two AAV models by upregulating antioxidants and inhibiting ROS-mediated NETs. Furthermore, Nrf2 activation restrained the expansion of splenic immune cells, including T lymphocytes and limited the infiltration of Th17 cells into the kidney. In contrast, Nrf2 genetic deficiency exacerbated vasculitis in a spontaneous AAV model. Thus, the pathophysiological process in AAV may be downregulated by Nrf2 activation, potentially leading to a new therapeutic strategy by regulating NETosis.
Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Modelos Animais de Doenças , Armadilhas Extracelulares , Camundongos Knockout , Fator 2 Relacionado a NF-E2 , Neutrófilos , Peroxidase , Espécies Reativas de Oxigênio , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Armadilhas Extracelulares/imunologia , Armadilhas Extracelulares/metabolismo , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/patologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/genética , Neutrófilos/imunologia , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peroxidase/metabolismo , Peroxidase/genética , Camundongos , Humanos , Estresse Oxidativo/imunologia , Camundongos Endogâmicos C57BL , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Glomerulonefrite/genética , Glomerulonefrite/metabolismo , Glomerulonefrite/etiologia , Anticorpos Anticitoplasma de Neutrófilos/imunologia , Masculino , Rim/patologia , Rim/imunologia , Transdução de Sinais/imunologiaRESUMO
Rapidly progressive/crescentic glomerulonephritis (RPGN/CGN) involves the formation of glomerular crescents by maladaptive differentiation of parietal epithelial cells that leads to rapid loss of renal function. The molecular mechanisms of crescent formation are poorly understood. Therefore, new insights into molecular mechanisms could identify alternative therapeutic targets for RPGN/CGN. Analysis of kidney biopsies from patients with RPGN revealed increased interstitial, glomerular, and tubular expression of STING1, an accessory protein of the c-GAS-dependent DNA-sensing pathway, which was also observed in murine nephrotoxic nephritis induced by an anti-GBM antibody. STING1 was expressed by key cell types involved in RPGN and crescent formation such as glomerular parietal epithelial cells, and tubular cells as well as by inflammation accessory cells. In functional in vivo studies, Sting1-/- mice with nephrotoxic nephritis had lower kidney cytokine expression, milder kidney infiltration by innate and adaptive immune cells, and decreased disease severity. Pharmacological STING1 inhibition mirrored these findings. Direct STING1 agonism in parietal and tubular cells activated the NF-κB-dependent cytokine response and the interferon-induced genes (ISGs) program. These responses were also triggered in a STING1-dependent manner by the pro-inflammatory cytokine TWEAK. These results identify STING1 activation as a pathological mechanism in RPGN/CGN and TWEAK as an activator of STING1. Pharmacological strategies targeting STING1, or upstream regulators may therefore be potential alternatives to treat RPGN. © 2023 The Pathological Society of Great Britain and Ireland.
Assuntos
Glomerulonefrite , Nefrite , Humanos , Camundongos , Animais , Glomerulonefrite/genética , Rim/patologia , Glomérulos Renais/patologia , Doença Aguda , Citocinas/metabolismoRESUMO
Genetic variation within the factor H-related (FHR) genes is associated with the complement-mediated kidney disease, C3 glomerulopathy (C3G). There is no definitive treatment for C3G, and a significant proportion of patients develop end-stage renal disease. The prototypical example is CFHR5 nephropathy, through which an internal duplication within a single CFHR5 gene generates a mutant FHR5 protein (FHR5mut) that leads to accumulation of complement C3 within glomeruli. To elucidate how abnormal FHR proteins cause C3G, we modeled CFHR5 nephropathy in mice. Animals lacking the murine factor H (FH) and FHR proteins, but coexpressing human FH and FHR5mut (hFH-FHR5mut), developed glomerular C3 deposition, whereas mice coexpressing human FH with the normal FHR5 protein (hFH-FHR5) did not. Like in patients, the FHR5mut had a dominant gain-of-function effect, and when administered in hFH-FHR5 mice, it triggered C3 deposition. Importantly, adeno-associated virus vector-delivered homodimeric mini-FH, a molecule with superior surface C3 binding compared to FH, reduced glomerular C3 deposition in the presence of the FHR5mut. Our data demonstrate that FHR5mut causes C3G by disrupting the homeostatic regulation of complement within the kidney and is directly pathogenic in C3G. These results support the use of FH-derived molecules with enhanced C3 binding for treating C3G associated with abnormal FHR proteins. They also suggest that targeting FHR5 represents a way to treat complement-mediated kidney injury.
Assuntos
Complemento C3/metabolismo , Proteínas do Sistema Complemento/genética , Mutação com Ganho de Função , Glomerulonefrite/genética , Glomerulonefrite/metabolismo , Glomérulos Renais/patologia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Glomérulos Renais/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Fatores SexuaisRESUMO
BACKGROUND: Circular RNAs (circRNAs) have been shown to play critical roles in the initiation and progression of chronic glomerulonephritis (CGN), while their role from mesangial cells in contributing to the pathogenesis of CGN is rarely understood. Our study aims to explore the potential functions of mesangial cell-derived circRNAs using RNA sequencing (RNA-seq) and bioinformatics analysis. METHODS: Mouse mesangial cells (MMCs) were stimulated by lipopolysaccharide (LPS) to establish an in vitro model of CGN. Pro-inflammatory cytokines and cell cycle stages were detected by Enzyme-linked immunosorbent assay (ELISA) and Flow Cytometry experiment, respectively. Subsequently, differentially expressed circRNAs (DE-circRNAs) were identified by RNA-seq. GEO microarrays were used to identify differentially expressed mRNAs (DE-mRNAs) between CGN and healthy populations. Weighted co-expression network analysis (WGCNA) was utilized to explore clinically significant modules of CGN. CircRNA-associated CeRNA networks were constructed by bioinformatics analysis. The hub mRNAs from CeRNA network were identified using LASSO algorithms. Furthermore, utilizing protein-protein interaction (PPI), gene ontology (GO), pathway enrichment (KEGG), and GSEA analyses to explore the potential biological function of target genes from CeRNA network. In addition, we investigated the relationships between immune cells and hub mRNAs from CeRNA network using CIBERSORT. RESULTS: The expression of pro-inflammatory cytokines IL-1ß, IL-6, and TNF-α was drastically increased in LPS-induced MMCs. The number of cells decreased significantly in the G1 phase but increased significantly in the S/G2 phase. A total of 6 DE-mRNAs were determined by RNA-seq, including 4 up-regulated circRNAs and 2 down-regulated circRNAs. WGCNA analysis identified 1747 DE-mRNAs of the turquoise module from CGN people in the GEO database. Then, the CeRNA networks, including 6 circRNAs, 38 miRNAs, and 80 mRNAs, were successfully constructed. The results of GO and KEGG analyses revealed that the target mRNAs were mainly enriched in immune, infection, and inflammation-related pathways. Furthermore, three hub mRNAs (BOC, MLST8, and HMGCS2) from the CeRNA network were screened using LASSO algorithms. GSEA analysis revealed that hub mRNAs were implicated in a great deal of immune system responses and inflammatory pathways, including IL-5 production, MAPK signaling pathway, and JAK-STAT signaling pathway. Moreover, according to an evaluation of immune infiltration, hub mRNAs have statistical correlations with neutrophils, plasma cells, monocytes, and follicular helper T cells. CONCLUSIONS: Our findings provide fundamental and novel insights for further investigations into the role of mesangial cell-derived circRNAs in CGN pathogenesis.
Assuntos
Biologia Computacional , Glomerulonefrite , Células Mesangiais , RNA Circular , RNA Circular/genética , RNA Circular/metabolismo , Animais , Camundongos , Células Mesangiais/metabolismo , Glomerulonefrite/genética , Glomerulonefrite/metabolismo , Análise de Sequência de RNA , Redes Reguladoras de Genes , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Mapas de Interação de Proteínas/genética , Doença Crônica , Citocinas/metabolismo , Lipopolissacarídeos/farmacologia , Perfilação da Expressão Gênica , Modelos Animais de DoençasRESUMO
The transcription factor Blimp1 is not only an essential regulator of plasma cells, but also a risk factor for the development of autoimmune disease in humans. Here, we demonstrate in the mouse that the Prdm1 (Blimp1) gene was partially activated at the chromatin and transcription level in early B cell development, although mature Prdm1 mRNA did not accumulate due to posttranscriptional regulation. By analyzing a mouse model that facilitated ectopic Blimp1 protein expression throughout B lymphopoiesis, we could demonstrate that Blimp1 impaired B cell development by interfering with the B cell gene expression program, while leading to an increased abundance of plasma cells by promoting premature plasmablast differentiation of immature and mature B cells. With progressing age, these mice developed an autoimmune disease characterized by the presence of autoantibodies and glomerulonephritis. Hence, these data identified ectopic Blimp1 expression as a novel mechanism, through which Blimp1 can act as a risk factor in the development of autoimmune disease.
Assuntos
Linfócitos B/metabolismo , Glomerulonefrite/metabolismo , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Fator 1 de Ligação ao Domínio I Regulador Positivo/metabolismo , Animais , Autoanticorpos/metabolismo , Linfócitos B/citologia , Diferenciação Celular , Modelos Animais de Doenças , Feminino , Redes Reguladoras de Genes , Glomerulonefrite/genética , Humanos , Masculino , Camundongos , Ativação TranscricionalRESUMO
BACKGROUND: Branchio-oto-renal (BOR) syndrome is an inherited multi-systemic disorder. Auricular and branchial signs are highly suggestive of BOR syndrome but often develop insidiously, leading to a remarkable misdiagnosis rate. Unlike severe morphological abnormalities of kidneys, knowledge of glomerular involvement in BOR syndrome were limited. CASE PRESENTATION: Three cases, aged 8 ~ 9 years, visited pediatric nephrology department mainly for proteinuria and renal insufficiency, with 24-h proteinuria of 23.8 ~ 68.9 mg/kg and estimated glomerular filtration rate of 8.9 ~ 36.0 mL/min/1.73m2. Moderate-to-severe albuminuria was detected in case 1, while mixed proteinuria was detected in case 2 and 3. Insidious auricular and branchial fistulas were noticed, all developing since early childhood but being neglected previously. EYA1 variants were confirmed by genetic testing in all cases. Delay in diagnosis was 8 ~ 9 years since extra-renal appearances, and 0 ~ 6 years since renal abnormalities. In case 1, therapy of glucocorticoid and immunosuppressive agents to accompanying immune-complex mediated glomerulonephritis was unsatisfying. CONCLUSIONS: BOR syndrome is a rare cause of proteinuria and abnormal kidney function and easily missed, thus requiring more awareness. Careful medical history taking and physical examination are essential to early diagnosis. Massive proteinuria was occasionally seen in BOR syndrome, which might be related to immune complex deposits. A novel pathogenic variant (NM_000503.6 (EYA1): c.1171delT p.Ser391fs*9) was firstly reported.
Assuntos
Síndrome Brânquio-Otorrenal , Glomerulonefrite , Insuficiência Renal , Pré-Escolar , Humanos , Criança , Síndrome Brânquio-Otorrenal/complicações , Síndrome Brânquio-Otorrenal/diagnóstico , Síndrome Brânquio-Otorrenal/genética , Insuficiência Renal/diagnóstico , Rim , Proteinúria/diagnóstico , Proteinúria/etiologia , Albuminúria , Glomerulonefrite/complicações , Glomerulonefrite/diagnóstico , Glomerulonefrite/genéticaRESUMO
Few genetically dominant mutations involved in human disease have been fully explained at the molecular level. In cases where the mutant gene encodes a transcription factor, the dominant-negative mode of action of the mutant protein is particularly poorly understood. Here, we studied the genome-wide mechanism underlying a dominant-negative form of the SOX18 transcription factor (SOX18RaOp) responsible for both the classical mouse mutant Ragged Opossum and the human genetic disorder Hypotrichosis-lymphedema-telangiectasia-renal defect syndrome. Combining three single-molecule imaging assays in living cells together with genomics and proteomics analysis, we found that SOX18RaOp disrupts the system through an accumulation of molecular interferences which impair several functional properties of the wild-type SOX18 protein, including its target gene selection process. The dominant-negative effect is further amplified by poisoning the interactome of its wild-type counterpart, which perturbs regulatory nodes such as SOX7 and MEF2C. Our findings explain in unprecedented detail the multi-layered process that underpins the molecular aetiology of dominant-negative transcription factor function.
Assuntos
Glomerulonefrite/genética , Hipotricose/genética , Linfedema/genética , Fatores de Transcrição SOXF/genética , Telangiectasia/genética , Transcrição Gênica , Animais , Células COS , Chlorocebus aethiops , Modelos Animais de Doenças , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Genes Reporter , Glomerulonefrite/metabolismo , Glomerulonefrite/patologia , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipotricose/metabolismo , Hipotricose/patologia , Luciferases/genética , Luciferases/metabolismo , Linfedema/metabolismo , Linfedema/patologia , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Camundongos , Mutação , Fatores de Transcrição SOXF/metabolismo , Imagem Individual de Molécula , Telangiectasia/metabolismo , Telangiectasia/patologiaRESUMO
Transcriptome profiling of tubulointerstitial tissue in glomerulonephritis may reveal a potential tubulointerstitial injury-related biomarker. We profiled manually microdissected tubulointerstitial tissue from biopsy cores of 65 glomerulonephritis cases, including 43 patients with IgA nephropathy, 3 with diabetes mellitus nephropathy, 3 with focal segmental glomerulosclerosis, 3 with lupus nephritis, 4 with membranous nephropathy and 9 with minimal change disease, and additional 22 nephrectomy controls by RNA sequencing. A potential biomarker was selected based on the false discovery rate, and experiments were performed in TNF-α-stimulated primary cultured human tubular epithelial cells (hTECs). We identified 3037 genes with low expression and 2852 genes with high expression in the disease samples compared to the controls. Dual-specificity phosphatase 1 (DUSP1) exhibited universal low expression in various diseases (log2 fold change, -3.87), with the lowest false discovery rate (7.03E-132). In further experimental validation study, DUSP1 overexpression ameliorated inflammatory markers related to MAP kinase pathways in hTECs, while pharmacologic inhibition of DUSP1 increased these markers. The combination of DUSP1 overexpression with low-concentration corticosteroid treatment resulted in more potent suppression of inflammation than high-concentration corticosteroid treatment alone. The profiled transcriptomes provide insights into the pathophysiology of tubulointerstitial injury in kidney diseases and may reveal a potential therapeutic biomarker.
Assuntos
Glomerulonefrite por IGA , Glomerulonefrite , Biomarcadores , Biópsia , Glomerulonefrite/tratamento farmacológico , Glomerulonefrite/genética , Glomerulonefrite por IGA/tratamento farmacológico , Glomerulonefrite por IGA/genética , Glomerulonefrite por IGA/metabolismo , Humanos , Monoéster Fosfórico Hidrolases , RNA-SeqRESUMO
Primary glomerulonephritis is a major global health concern and a disorder with significant heritable components. Rapid advances in sequencing technologies have led to genome-wide, high-throughput investigations of the genetic basis of complex human traits. Genetic studies have successfully mapped several susceptibility loci and disease-causing genes for different subtypes of primary glomerulonephritis. These studies have revealed that IgA nephropathy-associated genes have a highly complex, polygenic and pleiotropic genetic architecture and that genetic susceptibility to membranous nephropathy may be driven by a few large-effect loci. Furthermore, both susceptibility genes and high-penetrant gene mutations reportedly contribute to the development of the most heterogeneous phenotype of focal segmental glomerulosclerosis. The genetic heterogeneity between each glomerular disease type and within different populations has indicated disease-specific and ethnicity-specific underlying molecular mechanisms for the disorders. The findings from genome-wide association studies (GWAS) have mainly included variants on or near the major histocompatibility (MHC) loci, highlighting the molecular basis for the shared pathogenesis of the immune-mediated disease. Recent studies with increased sample sizes and higher resolutions of genome-wide imputation have provided novel insights into the pathogenesis of glomerular disorders. Further integration of results from genomic studies with functional genomics datasets can indicate novel targets for drug discovery as well as potential tools for patient diagnosis and stratification. However, larger GWASs and sequencing studies in independent cohorts and more standardized inclusion of phenotypes across studies are required for each subtype of glomerular disease.
Assuntos
Glomerulonefrite por IGA , Glomerulonefrite Membranosa , Glomerulonefrite , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Glomerulonefrite/diagnóstico , Glomerulonefrite/genética , Glomerulonefrite/patologia , Glomerulonefrite por IGA/diagnóstico , Glomerulonefrite por IGA/genética , Glomerulonefrite por IGA/patologia , Glomerulonefrite Membranosa/patologia , HumanosRESUMO
The inflammasome is an immune multiprotein complex that activates pro-caspase 1 in response to inflammation-inducing stimuli and it leads to IL-1ß and IL-18 proinflammatory cytokine production. NLRP1 and NLRP3 inflammasomes are the best characterized and they have been related to several autoimmune diseases. It is well known that the kidney expresses inflammasome genes, which can influence the development of some glomerulonephritis, such as lupus nephritis, ANCA glomerulonephritis, IgA nephropathy and anti-GBM nephropathy. Polymorphisms of these genes have also been described to play a role in autoimmune and kidney diseases. In this review, we describe the main characteristics, activation mechanisms, regulation and functions of the different inflammasomes. Moreover, we discuss the latest findings about the role of the inflammasome in several glomerulonephritis from three different points of view: in vitro, animal and human studies.
Assuntos
Glomerulonefrite , Inflamassomos , Animais , Caspase 1 , Feminino , Glomerulonefrite/genética , Humanos , Inflamação , Interleucina-1beta , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/genéticaRESUMO
Glomerulonephritis is the one of the major causes of the end-stage kidney disease, whereas the pathological process of glomerulonephritis is still not completely understood. Single-cell RNA sequencing (scRNA-seq) emerges to be a powerful tool to evaluate the full heterogeneity of kidney diseases. To reveal cellular gene expression profiles of glomerulonephritis, we performed scRNA-seq of 2 human kidney transplantation donor samples, 4 human glomerulonephritis samples, 1 human malignant hypertension (MH) sample and 1 human chronic interstitial nephritis (CIN) sample, all tissues were taken from the biopsy. After filtering the cells with < 200 genes and > 10% mitochondria (MT) genes, the resulting 14 932 cells can be divided into 20 cell clusters, consistently with the previous report, in disease samples dramatic immune cells infiltration was found, among which a proximal tubule (PT) subset characterized by wnt-ß catenin activation and a natural killer T (NKT) subset high expressing LTB were found. Furthermore, in the cluster of the podocyte, three glomerulonephritis related genes named FXYD5, CD74 and B2M were found. Compared with the mesangial of donor, the gene CLIC1 and RPS26 were up-regulated in mesangial of IgA nephropathy(IgAN), whereas the gene JUNB was up-regulated in podocyte of IgAN in comparison with that of donor. Meanwhile, some membranous nephropathy (MN) high expressed genes such as HLA-DRB5, HLA-DQA2, IFNG, CCL2 and NR4A2, which involve in highest enrichment pathway, display the cellular-specific expression style, whereas monocyte marker of lupus nephritis (LN) named TNFSF13B was also found and interferon alpha/beta signalling pathway was enriched in B and NKT of LN comparing with donor. By scRNA-seq, we first defined the podocyte markers of glomerulonephritis and specific markers in IgA, MN and LN were found at cellular level. Furthermore, the critical role of interferon alpha/beta signalling pathway was enriched in B and NKT of LN was declared.
Assuntos
Biomarcadores/metabolismo , Glomerulonefrite por IGA/patologia , Glomerulonefrite Membranosa/patologia , Glomerulonefrite/patologia , RNA-Seq/métodos , Análise de Célula Única/métodos , Adulto , Estudos de Casos e Controles , Feminino , Glomerulonefrite/genética , Glomerulonefrite/metabolismo , Glomerulonefrite por IGA/genética , Glomerulonefrite por IGA/metabolismo , Glomerulonefrite Membranosa/genética , Glomerulonefrite Membranosa/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Especificidade de ÓrgãosRESUMO
Co-stimulation is a prerequisite for pathogenic activity in T cell-mediated diseases and has been demonstrated to achieve tolerance in organ-specific autoimmunity as a therapeutic target. Here, we evaluated the involvement of the tumor necrosis factor family members CD30 and OX40 in immune-complex mediated kidney disease. In vitro stimulation and proliferation studies were performed with CD4+ cells from wild type and CD30/OX40 double knock-out (CD30OX40-/-) mice. In vivo studies were performed by induction of nephrotoxic serum nephritis in wild type, CD30OX40- /- , CD30-/-, OX40-/-, reconstituted Rag1-/- and C57Bl/6J mice treated with αCD30L αOX40L antibodies. CD30, OX40 and their ligands were upregulated on various leukocytes in nephrotoxic serum nephritis. CD30OX40-/- mice, but not CD30-/- or OX40-/- mice were protected from nephrotoxic serum nephritis. Similar protection was found in Rag1-/- mice injected with CD4+ T cells from CD30OX40-/- mice compared to Rag1-/- mice injected with CD4+ T cells from wild type mice. Furthermore, CD4+ T cells deficient in CD30OX40-/- displayed decreased expression of CCR6 in vivo. CD30OX40-/- cells were fully capable of differentiating into disease mediating T helper cell subsets, but showed significantly decreased levels of proliferation in vivo and in vitro compared to wild type cells. Blocking antibodies against CD30L and OX40L ameliorated nephrotoxic serum nephritis without affecting pan-effector or memory T cell populations. Thus, our results indicate disease promotion via CD30 and OX40 signaling due to facilitation of exaggerated T cell proliferation and migration of T helper 17 cells in nephrotoxic serum nephritis. Hence, co-stimulation blockade targeting the CD30 and OX40 signaling pathways may provide a novel therapeutic strategy in autoimmune kidney disease.
Assuntos
Glomerulonefrite , Receptores OX40 , Animais , Linfócitos T CD4-Positivos , Glomerulonefrite/genética , Antígeno Ki-1 , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator de Necrose Tumoral alfa , Fatores de Necrose TumoralRESUMO
Cgnz1 on chromosome 1 mapped into a 1.34 Mb region of chromosome 1 in NZM2328 confers the progression of immune complex (IC)-mediated glomerulonephritis (GN) from acute GN (aGN) to chronic GN (cGN) with severe proteinuria and end stage renal disease in female mice. This genetic locus mediates podocyte susceptibility to IC-mediated damage. Taking advantage of the published observation that Cgnz1 is derived from NZW and that NZW is susceptible to orchitis, epididymitis and vasitis while C57L/J is resistant to these diseases, the possibility that this genetic region also confers germ cells susceptible to damage with aspermatogenesis and sterility in an active experimental autoimmune orchitis (EAO) model was investigated. Male mice from multiple intrachromosome (chromosome 1) recombinant strains were subjected to immunization with a sperm homogenate in CFA with concomitant administration of Bordetella pertussis toxin. There was concordance of the progression from aGN to cGN, severe proteinuria and end stage renal disease with susceptibility of EAO in NZM2328 and its congenic strains with various chromosome 1 genetic intervals introgressed from C57L/J to NZM2328. Both resistant and susceptible strains made comparable anti-testis and anti-sperm Abs. Thus the genetic interval that determines susceptibility to EAO is identical to that of Cgnz1 and mapped to the 1.34 Mb region in chromosone 1. This region likely confers germ cells in the male gonad susceptible to damage by immunologically mediated inflammation. This region has been tentatively renamed Cgnz1/Eaoz1. These observations further emphasize the importance of end organ susceptibility to damage in the pathogenesis of both systemic and organ specific autoimmune diseases.
Assuntos
Doenças Autoimunes/imunologia , Predisposição Genética para Doença , Glomerulonefrite/imunologia , Falência Renal Crônica/imunologia , Orquite/imunologia , Animais , Doenças Autoimunes/etiologia , Doenças Autoimunes/genética , Feminino , Regulação da Expressão Gênica/imunologia , Glomerulonefrite/complicações , Glomerulonefrite/genética , Falência Renal Crônica/complicações , Falência Renal Crônica/genética , Masculino , Camundongos , Orquite/etiologia , Orquite/genéticaRESUMO
C3 glomerulopathy (C3G) is a rare renal disease characterized by predominant glomerular C3 staining. Complement alternative pathway dysregulation due to inherited complement defects is associated with C3G. To identify novel C3G-related genes, we screened 86 genes in the complement, coagulation and endothelial systems in 35 C3G patients by targeted genomic enrichment and massively parallel sequencing. Surprisingly, the most frequently mutated gene was VWF. Patients with VWF variants had significantly higher proteinuria levels, higher crescent formation and lower factor H (FH) levels. We further selected two VWF variants to transiently express the von Willebrand factor (vWF) protein, we found that vWF expression from the c.1519A > G variant was significantly reduced. In vitro results further indicated that vWF could regulate complement activation, as it could bind to FH and C3b, act as a cofactor for factor I-mediated cleavage of C3b. Thus, we speculated that vWF might be involved in the pathogenesis of C3G.
Assuntos
Complemento C3/metabolismo , Glomerulonefrite Membranoproliferativa/genética , Glomerulonefrite/genética , Fator de von Willebrand/genética , Adolescente , Adulto , Estudos de Casos e Controles , China , Estudos de Coortes , Complemento C3b/metabolismo , Fator H do Complemento/metabolismo , Via Alternativa do Complemento , Feminino , Variação Genética , Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Glomerulonefrite Membranoproliferativa/imunologia , Glomerulonefrite Membranoproliferativa/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Técnicas In Vitro , Glomérulos Renais/imunologia , Glomérulos Renais/patologia , Masculino , Pessoa de Meia-Idade , Modelos Imunológicos , Simulação de Dinâmica Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA , Adulto Jovem , Fator de von Willebrand/química , Fator de von Willebrand/metabolismoRESUMO
Focal segmental glomerulosclerosis (FSGS) is a commonly occurring cause of steroid-resistant nephrotic syndrome and frequently progresses to renal failure. Podocyte epithelial-mesenchymal transition (EMT) is thought to induce podocyte detachment in glomerular diseases, and severe degeneration and shedding of glomerular podocytes plays a major role in the progression of FSGS. We showed that fibroblast specific protein 1 (FSP1), an EMT marker, is strongly expressed in podocytes of FSGS patients, but the significance of podocyte expression of FSP1 to the pathophysiology of FSGS remained unclear. Here, we investigated FSP1 expression in podocytes from mice with adriamycin (ADR)-induced nephropathy, a murine model of FSGS. The number of FSP1-positive (FSP1+) podocytes was increased in ADR-treated mice and positively correlated with the degree of proteinuria and glomerulosclerosis in ADR-treated mice. ADR-induced FSGS and the attendant proteinuria were significantly ameliorated in FSP1 knockout mice as compared to wild type mice. These findings indicate that podocyte expression of FSP1 plays a crucial role in the pathogenesis of FSGS, which makes FSP1 a potential target for treatment of FSGS.
Assuntos
Doxorrubicina , Glomerulonefrite/induzido quimicamente , Proteína A4 de Ligação a Cálcio da Família S100/genética , Animais , Progressão da Doença , Expressão Gênica , Glomerulonefrite/genética , Glomerulonefrite/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Knockout , Podócitos/patologia , Proteína A4 de Ligação a Cálcio da Família S100/análiseRESUMO
PURPOSE OF REVIEW: Fibrillary glomerulonephritis (FGN) involves â¼1% of native kidney biopsies and is characterized by glomerular deposition of fibrils larger than amyloid (12-24ânm diameter) composed of polyclonal immunoglobulin G (IgG). The recent discovery of DNA J homolog subfamily B member 9 (DNAJB9) in FGN glomerular deposits has contributed a specific and sensitive biomarker, informing morphologic classification and pathogenesis. This review will consider contemporary FGN incidence and genetics, pathogenesis, (lack of) paraprotein association, variants, treatment, and transplantation. RECENT FINDINGS: DNAJB9 tissue assays have enabled the identification of morphologic variants and improved classification of fibrillary-like glomerular diseases. Together with paraffin immunofluorescence and IgG subclass studies, these have established that FGN is only rarely monoclonal and these patients usually do not have an monoclonal gammopathy. The discovery of DNAJB9 opens new avenues of investigation into FGN pathogenesis, especially those of the unfolded protein response. Treatment for FGN remains empiric, with some encouraging data on rituximab-based therapy. Transplantation is a good option for patients progressing to end-stage kidney disease. SUMMARY: Advances building on the discovery of DNAJB9 in FGN should lead to long-term evolution in targeted treatment and outcome of this glomerular disease.
Assuntos
Glomerulonefrite , Proteínas de Choque Térmico HSP40 , Proteínas de Membrana , Chaperonas Moleculares , Glomerulonefrite/diagnóstico , Glomerulonefrite/genética , Glomerulonefrite/terapia , HumanosRESUMO
As a hepadnavirus, hepatitis B virus (HBV) can cause damage to extrahepatic organs. The kidney is one of the organs that is more susceptible to damage. Research studies on HBV-associated glomerulonephritis (HBV-GN) have been going on for decades. However, the underlying molecular mechanism remains obscure. Here, we applied a tandem mass tag (TMT) isobaric labeling-based method to quantitatively profile the kidney proteome of HBV transgenic mice to illustrate the pathological mechanisms of HBV-GN. Weighted correlation network analysis, a clustering method for gene expression, is used to cluster proteins. Totally, we identified 127 proteins that were highly associated with HBV expression out of a total of 5169 quantified proteins. Among them, the downregulated solute carrier (SLC) family proteins are involved in the process of HBV-GN. We also found that IL1B was upregulated in the kidney tissue of HBV transgenic mice. These findings suggest that HBV disrupts the small molecule transport network of the kidney, which contributes to the occurrence of HBV-GN. The transporter, particularly SLC family 7 member 7 (SLC7A7), is involved in this process, which might serve as an intervention target for HBV-GN. All MS data have been deposited to the ProteomeXchange Consortium via the iProX partner repository with the data set identifier PXD016450.
Assuntos
Glomerulonefrite , Hepatite B , Sistema y+L de Transporte de Aminoácidos , Animais , Regulação para Baixo , Glomerulonefrite/genética , Hepatite B/complicações , Vírus da Hepatite B , Rim , Camundongos , ProteômicaRESUMO
Loss-of-function mutations in phospholipase C-ε1 (PLCE1) have been detected in patients with nephrotic syndrome, but other family members with the same mutation were asymptomatic, suggesting additional stressor are required to cause the full phenotype. Consistent with these observations, we determined that global Plce1-deficient mice have histologically normal glomeruli and no albuminuria at baseline. Angiotensin II (ANG II) is known to induce glomerular damage in genetically susceptible individuals. Therefore, we tested whether ANG II enhances glomerular damage in Plce1-deficient mice. ANG II increased blood pressure equally in Plce1-deficient and wild-type littermates. Additionally, it led to 20-fold increased albuminuria and significantly more sclerotic glomeruli in Plce1-deficient mice compared with wild-type littermates. Furthermore, Plce1-deficient mice demonstrated diffuse mesangial expansion, podocyte loss, and focal podocyte foot process effacement. To determine whether these effects are mediated by hypertension and hyperfiltration, rather than directly through ANG II, we raised blood pressure to a similar level using DOCA + salt + uninephrectomy and norepinephrine. This caused a fivefold increase in albuminuria in Plce1-deficient mice and a significant increase in the number of sclerotic glomeruli. Consistent with previous findings in mice, we detected strong PLCE1 transcript expression in podocytes using single cell sequencing of human kidney tissue. In hemagglutinin-tagged Plce1 transgenic mice, Plce1 was detected in podocytes and also in glomerular arterioles using immunohistochemistry. Our data demonstrate that Plce1 deficiency in mice predisposes to glomerular damage secondary to hypertensive insults.
Assuntos
Pressão Sanguínea , Glomerulonefrite/enzimologia , Hipertensão/enzimologia , Glomérulos Renais/enzimologia , Fosfoinositídeo Fosfolipase C/deficiência , Albuminúria/enzimologia , Albuminúria/genética , Albuminúria/fisiopatologia , Animais , Acetato de Desoxicorticosterona , Modelos Animais de Doenças , Feminino , Glomerulonefrite/genética , Glomerulonefrite/patologia , Glomerulonefrite/fisiopatologia , Hipertensão/genética , Hipertensão/fisiopatologia , Glomérulos Renais/patologia , Glomérulos Renais/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nefrectomia , Fosfoinositídeo Fosfolipase C/genética , Cloreto de Sódio na DietaRESUMO
Nephrotoxic serum nephritis (NTN) models immune-mediated human glomerulonephritis and culminates in kidney inflammation and fibrosis, a process regulated by T lymphocytes. TNF-α is a key proinflammatory cytokine that contributes to diverse forms of renal injury. Therefore, we posited that TNF-α from T lymphocytes may contribute to NTN pathogenesis. Here, mice with T cell-specific deletion of TNF-α (TNF TKO) and wild-type (WT) control mice were subjected to the NTN model. At 14 days after NTN, kidney injury and fibrosis were increased in kidneys from TNF TKO mice compared with WT mice. PD1+CD4+ T cell numbers and mRNA levels of IL-17A were elevated in NTN kidneys of TNF TKO mice, suggesting that augmented local T helper 17 lymphocyte responses in the TNF TKO kidney may exaggerate renal injury and fibrosis. In turn, we found increased accumulation of neutrophils in TNF TKO kidneys during NTN. We conclude that TNF-α production in T lymphocytes mitigates NTN-induced kidney injury and fibrosis by inhibiting renal T helper 17 lymphocyte responses and infiltration of neutrophils.