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1.
Pathol Res Pract ; 258: 155334, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38718468

RESUMO

Placental transmogrification of the lung (PTL) is a rare pulmonary condition characterized by the presence of immature placental villous structures. The etiology and molecular mechanisms underlying this disease remain largely unknown. This functional study aimed to identify the molecular signatures in the pathogenesis of PTL via comprehensive transcriptome analysis. Comparative transcriptomic assessment of PTL tissue and stromal cells showed differential expression of 257 genes in PTL tissue and 189 genes in stromal cells. Notably, several transcription factors and regulators, including FOSB, FOS, JUN, and ATF3, were upregulated in PTL tissue. Additionally, genes associated with the extracellular matrix and connective tissue, such as COL1A1, MMP2, and SPARC, were significantly altered, indicating possible fibrotic changes. Gene set enrichment analysis highlighted the role of vascular development and extracellular matrix organization, and the Activator Protein-1 (AP-1) transcription factor was significantly activated in PTL tissue. Furthermore, the analysis highlighted an overlap of 25 genes between PTL tissue and stromal cells, underscoring the importance of shared molecular pathways in the pathogenesis of PTL. Among the shared genes, JUND, COL4A2, COL6A2, IGFBP5, and IGFBP7 were consistently upregulated, highlighting the possible involvement of AP-1-mediated signaling and fibrotic changes in the pathogenesis of PTL. The present findings pave the way for further research into the molecular mechanisms underlying PTL and offer novel insights for therapeutic interventions. Given the rarity of PTL, these molecular findings represent a significant step forward in our understanding this enigmatic disease.


Assuntos
Perfilação da Expressão Gênica , Fator de Transcrição AP-1 , Humanos , Feminino , Fator de Transcrição AP-1/metabolismo , Fator de Transcrição AP-1/genética , Gravidez , Transcriptoma , Pulmão/patologia , Pulmão/metabolismo , Fibrose/patologia , Fibrose/genética , Placenta/patologia , Placenta/metabolismo , Pneumopatias/genética , Pneumopatias/patologia , Pneumopatias/metabolismo
2.
Pediatr Gastroenterol Hepatol Nutr ; 25(6): 441-452, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36451688

RESUMO

Congenital diarrheal disorders (CDDs) with genetic etiology are uncommon hereditary intestinal diseases characterized by chronic, life-threatening, intractable watery diarrhea that starts in infancy. CDDs can be mechanistically divided into osmotic and secretory diarrhea. Congenital tufting enteropathy (CTE), also known as intestinal epithelial dysplasia, is a type of secretory CDD. CTE is a rare autosomal recessive enteropathy that presents with intractable neonatal-onset diarrhea, intestinal failure, severe malnutrition, and parenteral nutrition dependence. Villous atrophy of the intestinal epithelium, crypt hyperplasia, and irregularity of surface enterocytes are the specific pathological findings of CTE. The small intestine and occasionally the colonic mucosa include focal epithelial tufts. In 2008, Sivagnanam et al. discovered that mutations in the epithelial cell adhesion molecule (EpCAM, MIM# 185535) were the genetic cause of CTE (MIM# 613217). More than a hundred mutations have been reported to date. Furthermore, mutations in the serine peptidase inhibitor Kunitz type 2 (SPINT2, MIM# 605124) have been linked to syndromic CTE. In this study, we report the case of a 17-month-old male infant with congenital diarrhea. Despite extensive etiological workup, no etiology could be established before admission to our center. The patient died 15 hours after being admitted to our center in a metabolically decompensated state, probably due to a delay in admission and diagnosis. Molecular autopsy with exome sequencing revealed a previously reported homozygous missense variant, c.757G>A, in EpCAM, which was confirmed by histopathological examination.

3.
Turk J Pediatr ; 64(1): 59-68, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35286031

RESUMO

BACKGROUND: Crescentic glomerulonephritis (CGN) is a rapidly progressive and rare cause of glomerulonephritis in childhood. The aim of this study is to evaluate demographic data of children with crescentic glomerulonephritis, to classify the etiologies and to investigate the correlation between the severity of kidney disease and the expression of CD163+ macrophages. METHODS: Between the years 2000 and 2016 in a single center, patients under 18 years of age with kidney biopsies containing crescents were included in the study. A total of 88 children were enrolled. The expression of CD163 in kidney tissues was detected by immunohistochemistry in 61 patients. Clinical features and outcome were collected from their medical records. RESULTS: The most common etiology was Henoch-Schönlein purpura (HSP) nephritis/Immunglobulin A vasculitis (26.1%), followed by lupus nephritis (22.7%) and idiopathic crescentic glomerulonephritis (18.2%). CD163 positive cell counts in patients with GFR levels less and more than 60 ml/min/1.73 m2 at their last visit were 7.6±6.6 cells vs. 2.0±3.0 cells (p=0.057) per one glomerulus and 52.2±18.2 cells/hpf vs. 33.3±10.0 cells/hpf (p < 0.05) in tubulointerstitium, respectively. Tubulointerstitital CD163+ cells were also found to be higher in patients with end stage kidney disease than complete and partial responders (68 cells/hpf vs 39 cells/hpf, p < 0.05). CONCLUSIONS: CD163 positive cell counts, particularly in tubulointerstitial areas, have been associated with poor prognosis of CGN.


Assuntos
Glomerulonefrite Membranoproliferativa , Glomerulonefrite , Falência Renal Crônica , Adolescente , Criança , Feminino , Glomerulonefrite/etiologia , Glomerulonefrite Membranoproliferativa/complicações , Humanos , Glomérulos Renais/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino
4.
J Pediatr Intensive Care ; 11(1): 77-82, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35178282

RESUMO

Cardiac myxoma is rare in children. Myxomas are exceedingly rare in infancy. Right atrial myxomas were recorded in a small number of case reports involving infants worldwide. We report the case of a 2-month-old infant with giant right atrial myxoma. The case presented to our hospital with respiratory distress, and had pericardial and pleural effusion. Diagnosis of cardiac tumor was made with the aid of computerized tomography scan and echocardiogram. The tumor size was 3.1 × 3.4 × 3.9 cm. The patient worsened rapidly and had sudden cardiac arrest which did not respond to interventions. Postmortem cardiac autopsy confirmed the diagnosis of myxoma on gross examination and histology. This article aims to focus attention to the atypical size and location of this atrial myxoma, causing diagnostic difficulty in this infant.

5.
Fetal Pediatr Pathol ; 41(5): 843-851, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34622726

RESUMO

Introduction: One-third of fetal soft tissue tumors are malignant and include congenital fibrosarcoma (CF). We report two fetal CFs arising in the posterior mediastinum. Case Presentation: In case 1, the CF resulted in a mediastinal shift, extensive infiltration of the tumor around adjacent structures, pulmonary hypoplasia, pleural effusion, and rapid growth. The pregnancy was terminated. Case 2 had multiple intrathoracic masses, thoracic hypoplasia, pleural effusion, and fetal death. Both were diagnosed as fibrosarcoma at fetopsy. Discussion: Although congenital CF tends to be locally aggressive with a low metastatic rate, it tends to grow rapidly and the tumor location can affect fetal survival. In Case 1, the tumor demonstrated locally aggressive behavior whereas multiple distant metastases such as lung, liver, adrenals, and left eye were detected in Case 2. The tumor was directly responsible for intrauterine fetal demise in the second case.


Assuntos
Fibrossarcoma , Derrame Pleural , Neoplasias de Tecidos Moles , Feminino , Feto/patologia , Fibrossarcoma/diagnóstico , Fibrossarcoma/patologia , Humanos , Mediastino/patologia , Gravidez , Neoplasias de Tecidos Moles/diagnóstico
8.
Turk J Pediatr ; 63(4): 708-715, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34449155

RESUMO

BACKGROUND: Mesenteric lymphadenopathy is a rare manifestation of Gaucher disease (GD) in children and can be accompanied by protein losing enteropathy (PLE). PLE is a difficult-to-treat complication of GD. To date, only a few pediatric GD cases with PLE and massive mesenteric lymphadenopathies have been reported. CASE: Here, we report a girl with chronic neuronopathic GD, whose disease course was complicated by massive mesenteric lymphadenopathies with resultant protein losing enteropathy despite a regular and appropriate enzyme replacement therapy of 60 IU/kg/biweekly until the development of mesenteric lymphadenopathies and 120 IU/kg/biweekly thereafter. CONCLUSIONS: PLE is a devastating and life threatening complication of GD developing despite long term use of high dose ERT. Clinicians should be alert for this complication particularly in GD patients presenting with progressive abdominal distension, edema, ascites and diarrhea or in patients who have already developed mesenteric lymphadenopathies. Timely diagnosis may allow early intervention with previously suggested surgical or medical treatment options. Although there is no specific and effective treatment, surgical and aggressive medical interventions in addition to ERT were reported to relieve diarrhea and halt progression of mesenteric lymphadenopathies.


Assuntos
Doença de Gaucher , Linfadenopatia , Enteropatias Perdedoras de Proteínas , Criança , Terapia de Reposição de Enzimas , Feminino , Doença de Gaucher/complicações , Doença de Gaucher/diagnóstico , Doença de Gaucher/terapia , Humanos , Enteropatias Perdedoras de Proteínas/diagnóstico , Enteropatias Perdedoras de Proteínas/etiologia , Enteropatias Perdedoras de Proteínas/terapia , Resultado do Tratamento
9.
Rheumatol Int ; 41(1): 77-85, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33106894

RESUMO

Juvenile dermatomyositis (JDM) is an inflammatory myopathy which causes severe morbidity and high mortality if untreated. In this study, we aimed to define the T-helper cell profile in the muscle biopsies of JDM patients. Muscle biopsies of twenty-six patients (50% female) were included in the study. Immunohistochemical expression of CD3, CD20, CD138, CD68, IL-17, Foxp3, IFN-É£, IFN-alpha and IL-4 was studied and muscle biopsies were scored using the JDM muscle biopsy scoring tool. Inflammatory cells were in small clusters in perimysium and perivascular area or scattered throughout the endomysium in most biopsies; however in 2 biopsies, lymphoid follicle-like big clusters were observed, and in one, there was a very dense and diffuse inflammatory infiltration nearly destroying all the muscle architecture. Seventy-three per cent of the biopsies had T cells, 88% had B cells, 57% had plasma cells, and all had macrophages. As for T-helper cell subtypes, 80% of the biopsies were Th1 positive, 92% Th17 positive and 30% Treg positive. No IL-4 positive inflammatory cell was detected, and only 2 biopsies showed IFN-alpha positivity. The mean JDM biopsy score was 17.6, meaning moderate to severe muscular involvement. Visual analogue score of the pathologist was strongly correlated with histopathological features. B cells, macrophages, plasma cells and T cells constitute the inflammatory milieu of the JDM muscle biopsies. As for T cells, JDM is a disease mainly related with Th1 and Th17 T-helper cell subtypes and to some extend Treg. Th2 cells are not involved in the pathogenesis.


Assuntos
Dermatomiosite/imunologia , Músculo Quadríceps/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adolescente , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/patologia , Biópsia , Criança , Pré-Escolar , Dermatomiosite/patologia , Feminino , Humanos , Lactente , Masculino , Músculo Quadríceps/patologia , Estudos Retrospectivos , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos T Auxiliares-Indutores/patologia
10.
Fetal Pediatr Pathol ; 39(2): 163-171, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31303091

RESUMO

INTRODUCTION: Sengers syndrome is an autosomal recessive disorder characterized by congenital cataracts, hypertrophic cardiomyopathy, skeletal myopathy and lactic acidosis. The causative AGK mutations have been identified with whole exome sequencing. CLINICAL REPORT: We report on a 9-month-old infant with episodic lactic acidosis who died before a definitive diagnosis could be established. Postmortem genomic autopsy revealed a novel homozygous NM_018238: c.1215dupG; p.Phe406Valfs*4 mutation in AGK (OMIM 610345) confirming the diagnosis of Sengers syndrome. CONCLUSION: This report provides further evidence that reverse genetics is a useful approach in patients who do not manifest the hallmark features of known and recognizable syndromes.


Assuntos
Cardiomiopatias/genética , Cardiomiopatias/patologia , Catarata/genética , Catarata/patologia , Mutação/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Autopsia/métodos , Cardiomiopatias/diagnóstico , Catarata/diagnóstico , Feminino , Testes Genéticos/métodos , Humanos , Lactente , Masculino , Mitocôndrias/genética , Fenótipo
11.
Turk J Pediatr ; 61(1): 111-116, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31559731

RESUMO

Düzova A, Gülhan B, Topaloglu R, Özaltin F, Cengiz AB, Yetimakman AF, Dogru D, Güçer S, Besbas N. BK virus associated nephropathy and severe pneumonia in a kidney transplanted adolescent with Schimke immune-osseous-dysplasia. Turk J Pediatr 2019; 61: 111-116. Patients with juvenile onset Schimke immune-osseous-dysplasia (SIOD) have less severe symptoms and can survive in the second and third decade of life. We present an 18 year-old adolescent with juvenile onset SIOD who was diagnosed after renal transplantation and developed BK virus associated nephropathy (BKVAN) and severe pneumonia during follow-up. The patient developed nephrotic syndrome, unresponsive to immunosuppressives, at the age of 8 years. He had a history of meningitis, short stature, microcephaly, prominent ears, and bilateral cryptorchidism. A renal transplantation was performed at the age of 15 years. During follow-up, he suffered from leucopenia, urinary tract infections, herpes labialis, and candida esophagitis. Sanger sequencing of SMARCAL1 revealed a missense mutation on exon 11 (R586W). A renal biopsy performed after a sharp increase in serum creatinine (without significant viremia) revealed BKVAN which responded to sirolimus monotherapy and cidofovir. Three months later, he suffered from productive cough and dyspnea with diffuse ground glass pulmonary infiltrates. His clinical situation deteriorated and non-invasive mechanical ventilation was started. Cidofovir (2 mg/kg) was re-started weekly for a possible BKV pneumonia with intravenous immunoglobulin. After 5 doses of cidofovir and intense antibiotic regime, his dyspnea resolved with stable graft functions. In our case; BKVAN, which developed without significant viremia, and possibly associated pneumonia were treated successfully with cidofovir and sirolimus monotherapy.


Assuntos
Síndrome Nefrótica/virologia , Pneumonia Viral/complicações , Infecções por Polyomavirus/complicações , Transplantados , Adolescente , Arteriosclerose/complicações , Vírus BK , DNA Helicases/genética , Humanos , Transplante de Rim , Masculino , Mutação de Sentido Incorreto , Síndrome Nefrótica/complicações , Osteocondrodisplasias/complicações , Doenças da Imunodeficiência Primária/complicações , Embolia Pulmonar/complicações
13.
Pediatr Neurol ; 88: 71-74, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30337132

RESUMO

BACKGROUND: COQ2 mutations cause a rare infantile multisystemic disease with heterogeneous clinical features. Promising results have been reported in response to Coenzyme Q10 treatment, especially for kidney involvement, but little is known about the long-term outcomes. METHODS: We report four new patients from two families with the c.437G→A (p.Ser146Asn) mutation in COQ2 and the outcomes of two patients after long-term coenzyme Q10 treatment. RESULTS: Index cases from two families presented with vomiting, nephrotic range proteinuria, and diabetes in early infancy. These patients were diagnosed with coenzyme Q10 deficiency and died shortly after diagnosis. Siblings of the index cases later presented with neonatal diabetes and proteinuria and were diagnosed at the first day of life. Coenzyme Q10 treatment was started immediately. The siblings responded dramatically to coenzyme Q10 treatment with normalized glucose and proteinuria levels, but they developed refractory focal clonic seizures beginning at three months of life that progressed to encephalopathy. CONCLUSIONS: In our cohort with CoQ10 deficiency, neurological involvement did not improve with oral coenzyme Q10 treatment despite the initial recovery from the diabetes and nephrotic syndrome.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/genética , Ataxia/dietoterapia , Ataxia/genética , Doenças Mitocondriais/dietoterapia , Doenças Mitocondriais/genética , Debilidade Muscular/dietoterapia , Debilidade Muscular/genética , Ubiquinona/análogos & derivados , Ubiquinona/deficiência , Ataxia/complicações , Ataxia/diagnóstico por imagem , Estudos de Coortes , Diabetes Mellitus/etiologia , Saúde da Família , Feminino , Humanos , Lactente , Rim/patologia , Rim/ultraestrutura , Imageamento por Ressonância Magnética , Masculino , Doenças Mitocondriais/complicações , Doenças Mitocondriais/diagnóstico por imagem , Debilidade Muscular/complicações , Debilidade Muscular/diagnóstico por imagem , Mutação/genética , Proteinúria/etiologia , Ubiquinona/genética , Ubiquinona/uso terapêutico
14.
Fetal Pediatr Pathol ; 37(3): 177-183, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29737941

RESUMO

OBJECTIVE: We aimed to evaluate fetuses of terminated pregnancies with oligo-or anhydramnios (OAH) to further investigate the association between maternal methylenetetrahydrofolate reductase (MTHFR) polymorphisms and fetal urinary tract malformations. MATERIALS AND METHODS: This retrospective study included 16 pregnancies with OAH (with normal fetal karyotype) that were intentionally terminated before 22nd gestational week. Fetal autopsy was performed in all cases. We evaluated cases for presence of DNA methylation pathway-related gene polymorphisms. RESULTS: We demonstrated that renal abnormalities and disorders exist in 75% of the cases. Pulmonary system anomalies and single umbilical artery were the most frequently observed associated abnormalities. Polymorphisms with known reduced MTHFR activity were found in 81.8% (9/11) of the cases.Association between urinary system abnormalities and polymorphisms with known reduced MTHFR activity was observed in 88.8% (8/9) of the cases. CONCLUSION: Physicians should keep in mind that polymorphisms with known reduced MTHFR activity may be associated with urinary tract abnormalities and OAH.


Assuntos
Feto/anormalidades , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Oligo-Hidrâmnio/genética , Sistema Urinário/anormalidades , Feminino , Humanos , Polimorfismo de Nucleotídeo Único , Gravidez , Estudos Retrospectivos
15.
Turk J Pediatr ; 60(5): 471-477, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30968631

RESUMO

Kayki G, Güçer S, Akçören Z, Orhan D, Talim B, Yurdakök M, Yigit S, Boduroglu OK, Utine GE, Örgül G, Beksac MS. Non-immune hydrops fetalis: A retrospective analysis of 151 autopsies performed at a single center. Turk J Pediatr 2018; 60: 471-477. We retrospectively evaluated autopsies performed on 151 non-immune hydrops fetalis (NIHF) cases to determine the etiology and pathological findings. Further, cases identified between 1980 and 2004 were compared with those identified between 2005 and 2015 to investigate the improvement of diagnostic performance of our institution. The mean gestational age during the fetal autopsy was 25 weeks. There were 30 live-born infants in the study group. The etiology of NIHF could be determined in 91 cases (60.3%), while it remained undefined in remaining 60 cases. The most commonly associated pathological conditions were cardiovascular malformations (11.3%), followed by chromosomal abnormalities (9.3%). Prior to 20th gestation week, genetic anomalies and cystic hygromas were the most common etiological factors, and after 30 weeks of gestation, cardiac abnormalities were found to be the most common causes. With time, the rate of undefined cases decreased from 48.4% to 33.75%. NIHF is a complex medical condition necessitating a multidisciplinary management approach. Progress in molecular genetics and imaging techniques is expected to improve diagnostic performance for rapid and better identification.


Assuntos
Hidropisia Fetal/patologia , Autopsia/estatística & dados numéricos , Aberrações Cromossômicas/estatística & dados numéricos , Feminino , Feto/patologia , Idade Gestacional , Humanos , Hidropisia Fetal/etiologia , Masculino , Gravidez , Sistema de Registros , Estudos Retrospectivos
16.
Fetal Pediatr Pathol ; 36(6): 445-451, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29220612

RESUMO

INTRODUCTION: Ovotesticular disorder of sex development (OT-DSD) is a rare disorder of sexual differentiation characterized by the presence of both testicular and ovarian tissue in an individual and the majority of cases have been reported with 46,XX karyotype. In 46,XX cases, testicular differentiation may occur due to the translocation of SRY to the X chromosome or to an autosome. CASE REPORT: Herein, we present a female newborn with a combination of trisomy 13 and SRY (-) XX OT-DSD. CONCLUSION: Trisomy 13 is a relatively common and well-known chromosomal disorder in which disorders of sexual differentiation are not frequent. In the absence of SRY, overexpression of pro-testis genes, or decreased expression of pro-ovarian/anti-testis genes have been suggested as underlying mechanisms of testicular formation. The findings in this patient were suggestive of an underlying genomic disorder associated with FGF9 and/or SPRY2.


Assuntos
Transtornos do Desenvolvimento Sexual/genética , Fator 9 de Crescimento de Fibroblastos/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Fatores de Transcrição SOXB1/genética , Síndrome da Trissomia do Cromossomo 13/genética , Transtornos do Desenvolvimento Sexual/complicações , Feminino , Fibroblastos/metabolismo , Humanos , Recém-Nascido , Cariotipagem , Translocação Genética , Síndrome da Trissomia do Cromossomo 13/complicações
18.
Clin Dysmorphol ; 26(1): 1-12, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27547915

RESUMO

We present a novel multisystem disease in two siblings with clinical features resembling a lysosomal storage disease. These included coarse face, dysostosis multiplex, respiratory difficulty, proteinuria with glomerular foamy cells, neurological involvement with developmental delays, pyramidal signs, and severe chronic anemia. Detailed enzymatic analysis for lysosomal diseases and whole-exome sequencing studies excluded known lysosomal storage diseases in the proband. Subsequently, genome-wide genotyping and exome sequencing analysis of the family indicated two large homozygous regions on chromosomes 5 and 12, and strongly suggested that a homozygous p. R498W missense mutation in the VPS33A gene might be responsible for this novel disease. Segregation analysis in family members and mutation prediction tools' results also supported the damaging effect of the missense mutation on the function of the Vps33a protein, which plays a role in the vesicular transport system. Electron microscopic studies of the cornea of the proband showed findings supportive of dysfunction in vesicular transport. The clinical phenotype and genetic studies support the suggestion that the siblings most probably have a novel disease very likely caused by a VPS33A gene defect.


Assuntos
Estudos de Associação Genética , Doenças por Armazenamento dos Lisossomos/diagnóstico , Doenças por Armazenamento dos Lisossomos/genética , Mutação , Fenótipo , Proteínas de Transporte Vesicular/genética , Biópsia , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Pré-Escolar , Fácies , Evolução Fatal , Feminino , Humanos , Lactente , Linhagem , Radiografia , Irmãos , Síndrome , Tomografia Computadorizada por Raios X
19.
Am J Hum Genet ; 98(6): 1130-1145, 2016 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-27259049

RESUMO

Multiple acyl-CoA dehydrogenase deficiencies (MADDs) are a heterogeneous group of metabolic disorders with combined respiratory-chain deficiency and a neuromuscular phenotype. Despite recent advances in understanding the genetic basis of MADD, a number of cases remain unexplained. Here, we report clinically relevant variants in FLAD1, which encodes FAD synthase (FADS), as the cause of MADD and respiratory-chain dysfunction in nine individuals recruited from metabolic centers in six countries. In most individuals, we identified biallelic frameshift variants in the molybdopterin binding (MPTb) domain, located upstream of the FADS domain. Inasmuch as FADS is essential for cellular supply of FAD cofactors, the finding of biallelic frameshift variants was unexpected. Using RNA sequencing analysis combined with protein mass spectrometry, we discovered FLAD1 isoforms, which only encode the FADS domain. The existence of these isoforms might explain why affected individuals with biallelic FLAD1 frameshift variants still harbor substantial FADS activity. Another group of individuals with a milder phenotype responsive to riboflavin were shown to have single amino acid changes in the FADS domain. When produced in E. coli, these mutant FADS proteins resulted in impaired but detectable FADS activity; for one of the variant proteins, the addition of FAD significantly improved protein stability, arguing for a chaperone-like action similar to what has been reported in other riboflavin-responsive inborn errors of metabolism. In conclusion, our studies identify FLAD1 variants as a cause of potentially treatable inborn errors of metabolism manifesting with MADD and shed light on the mechanisms by which FADS ensures cellular FAD homeostasis.


Assuntos
Mutação da Fase de Leitura/genética , Doenças Mitocondriais/genética , Deficiência Múltipla de Acil Coenzima A Desidrogenase/genética , Nucleotidiltransferases/genética , Riboflavina/farmacologia , Complexo Vitamínico B/farmacologia , Adulto , Western Blotting , Estudos de Casos e Controles , Células Cultivadas , Transporte de Elétrons , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Flavina-Adenina Dinucleotídeo/metabolismo , Perfilação da Expressão Gênica , Humanos , Lactente , Recém-Nascido , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Doenças Mitocondriais/tratamento farmacológico , Doenças Mitocondriais/patologia , Deficiência Múltipla de Acil Coenzima A Desidrogenase/tratamento farmacológico , Deficiência Múltipla de Acil Coenzima A Desidrogenase/patologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Mutagênese Sítio-Dirigida , Ligação Proteica , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Adulto Jovem
20.
J Am Soc Nephrol ; 27(1): 63-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25967120

RESUMO

Hereditary defects of coenzyme Q10 biosynthesis cause steroid-resistant nephrotic syndrome (SRNS) as part of multiorgan involvement but may also contribute to isolated SRNS. Here, we report 26 patients from 12 families with recessive mutations in ADCK4. Mutation detection rate was 1.9% among 534 consecutively screened cases. Patients with ADCK4 mutations showed a largely renal-limited phenotype, with three subjects exhibiting occasional seizures, one subject exhibiting mild mental retardation, and one subject exhibiting retinitis pigmentosa. ADCK4 nephropathy presented during adolescence (median age, 14.1 years) with nephrotic-range proteinuria in 44% of patients and advanced CKD in 46% of patients at time of diagnosis. Renal biopsy specimens uniformly showed FSGS. Whereas 47% and 36% of patients with mutations in WT1 and NPHS2, respectively, progressed to ESRD before 10 years of age, ESRD occurred almost exclusively in the second decade of life in ADCK4 nephropathy. However, CKD progressed much faster during adolescence in ADCK4 than in WT1 and NPHS2 nephropathy, resulting in similar cumulative ESRD rates (>85% for each disorder) in the third decade of life. In conclusion, ADCK4-related glomerulopathy is an important novel differential diagnosis in adolescents with SRNS/FSGS and/or CKD of unknown origin.


Assuntos
Glomerulosclerose Segmentar e Focal/genética , Mutação , Proteínas Quinases/genética , Adolescente , Idade de Início , Criança , Pré-Escolar , Humanos , Lactente
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