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1.
Hum Mol Genet ; 31(9): 1389-1406, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-34761259

RESUMO

Autism spectrum disorder (ASD) and intellectual disability (ID) often exist together in patients. The RAB39B gene has been reported to be mutated in ID patients with additional clinical features ranging from ASD, macrocephaly, seizures and/or early-onset parkinsonism. Here, we describe a novel RAB39B nonstop mutation [Xq28; c.640 T > C; p.(*214Glnext*21)] in a family with ASD, severe ID and poor motor coordination, and we assessed the pathogenicity of the mutation. A heterologous cell system and a Rab39b knockdown (KD) murine model, which mimic the nonstop mutation, were used to validate the deleterious effect of the RAB39B mutation. The mutation led to RAB39B protein instability, resulting in its increased degradation and consequent downregulation. Using a Rab39b KD mouse model, we demonstrated that the downregulation of RAB39B led to increased GluA2 lacking Ca2+-permeable AMPAR composition at the hippocampal neuronal surface and increased dendritic spine density that remained in an immature filopodia-like state. These phenotypes affected behavioural performance in a disease-specific manner. Rab39b KD mice revealed impaired social behaviour but intact social recognition. They also showed normal anxiety-like, exploratory and motivational behaviours but impaired working and associative memories. In conclusion, we found a novel RAB39B nonstop variant that segregated in a family with a clinical phenotype including ID, ASD and poor motor coordination. The pathogenicity of mutations causing the downregulation of RAB39B proteins, impacting AMPAR trafficking and dendritic spine morphogenesis, reinforced the idea that AMPAR modulation and dendritic spine assets could be considered hallmarks of neurodevelopmental disorders.


Assuntos
Transtorno do Espectro Autista , Deficiência Intelectual , Animais , Transtorno do Espectro Autista/genética , Modelos Animais de Doenças , Regulação para Baixo , Humanos , Deficiência Intelectual/genética , Camundongos , Mutação , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
2.
Prenat Diagn ; 42(13): 1575-1586, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36403097

RESUMO

OBJECTIVES: To establish the positive predictive values (PPV) of cfDNA testing based on data from a nationwide survey of independent clinical cytogenetics laboratories. METHODS: Prenatal diagnostic test results obtained by Italian laboratories between 2013 and March 2020 were compiled for women with positive non-invasive prenatal tests (NIPT), without an NIPT result, and cases where there was sex discordancy between the NIPT and ultrasound. PPV and other summary data were reviewed. RESULTS: Diagnostic test results were collected for 1327 women with a positive NIPT. The highest PPVs were for Trisomy (T) 21 (624/671, 93%) and XYY (26/27, 96.3%), while rare autosomal trisomies (9/47, 19.1%) and recurrent microdeletions (8/55, 14.5%) had the lowest PPVs. PPVs for T21, T18, and T13 were significantly higher when diagnostic confirmation was carried out on chorionic villi (97.5%) compared to amniotic fluid (89.5%) (p < 0.001). In 19/139 (13.9%), of no result cases, a cytogenetic abnormality was detected. Follow-up genetic testing provided explanations for 3/6 cases with a fetal sex discordancy between NIPT and ultrasound. CONCLUSIONS: NIPT PPVs differ across the conditions screened and the tissues studied in diagnostic testing. This variability, issues associated with fetal sex discordancy, and no results, illustrate the importance of pre- and post-test counselling.


Assuntos
Ácidos Nucleicos Livres , Feminino , Humanos , Gravidez , Análise Citogenética , Valor Preditivo dos Testes , Diagnóstico Pré-Natal/métodos , Trissomia/diagnóstico , Trissomia/genética , Síndrome da Trissomia do Cromossomo 13/diagnóstico , Síndrome da Trissomía do Cromossomo 18/diagnóstico , Itália
3.
Adv Neonatal Care ; 22(2): 125-131, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33852449

RESUMO

BACKGROUND: Filamin A (FLNA) is an intracellular actin-binding protein, encoded by the FLNA gene, with a wide tissue expression. It is involved in several cellular functions, and extracellular matrix structuring. FLNA gene alterations lead to diseases with a wide phenotypic spectrum, such as brain periventricular nodular heterotopia (PVNH), cardiovascular abnormalities, skeletal dysplasia, and lung involvement. CLINICAL FINDINGS: We present the case of a female infant who showed at birth aortic valve stenosis and PVNH, and subsequently developed interstitial lung disease with severe pulmonary hypertension. PRIMARY DIAGNOSIS: The association of aortic valve dysplasia, left ventricular outflow obstruction, persistent patent ductus arteriosus, and brain heterotopic gray matter suggested a possible FLNA gene alteration. A novel heterozygous intronic variant in the FLNA gene (NM_001110556.1), c.4304-1G >A, was detected. INTERVENTIONS: In consideration of valve morphology and severity of stenosis, the neonate was scheduled for a transcatheter aortic valvuloplasty. At 3 months of life, she developed hypoxemic respiratory failure with evidence of severe pulmonary hypertension. Inhaled nitric oxide (iNO) and milrinone on continuous infusion were started. Because of a partial response to iNO, an intravenous continuous infusion of sildenafil was introduced. OUTCOMES: In consideration of severe clinical course and fatal outcome, the new FLNA gene mutation described in our patient seems to be associated with a loss of function of FLNA. PRACTICE RECOMMENDATIONS: Lung and brain involvement, in association with left ventricular outflow obstruction and persistent patency of ductus arteriosus, should be considered highly suggestive of FLNA gene alterations, in a female newborn.


Assuntos
Hipertensão Pulmonar , Heterotopia Nodular Periventricular , Obstrução do Fluxo Ventricular Externo , Encéfalo/diagnóstico por imagem , Feminino , Filaminas/genética , Humanos , Hipertensão Pulmonar/genética , Lactente , Recém-Nascido , Pulmão/diagnóstico por imagem , Mutação , Heterotopia Nodular Periventricular/genética
4.
Clin Genet ; 99(3): 425-429, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33236357

RESUMO

mTOR dysregulation has been described in pathological conditions, such as cardiovascular and overgrowth disorders. Here we report on the first case of a patient with a complex congenital heart disease and an interstitial duplication in the short arm of chromosome 1, encompassing part of the mTOR gene. Our results suggest that an intragenic mTOR microduplication might play a role in the pathogenesis of non-syndromic congenital heart defects (CHDs) due to an upregulation of mTOR/Rictor and consequently an increased phosphorylation of PI3K/AKT and MEK/ERK signaling pathways in patient-derived amniocytes. This is the first report which shows a causative role of intragenic mTOR microduplication in the etiology of an isolated complex CHD.


Assuntos
Predisposição Genética para Doença , Cardiopatias Congênitas/genética , Cardiopatias Congênitas/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Cromossomos Humanos Par 1 , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Cardiopatias Congênitas/diagnóstico , Humanos , Lactente , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Mutação , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Regulação para Cima
5.
Am J Med Genet A ; 185(6): 1897-1902, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33750022

RESUMO

RASopathies are a group of syndromes with partially overlapping clinical features caused by germline mutations of the RAS/MAPK signaling pathway genes. The most common disorder is Noonan syndrome (NS; MIM 163950). We report the first prenatal case of NS with SOS2 (NM_006939.4) mutation in a euploid fetus with a severe increase in nuchal translucency (NT > 12 mm). Trio-based custom next-generation sequencing detected a de novo heterozygous missense mutation in the SOS2 gene: c.800 T > A (p.Met267Lys). Owing to the marked variable expressivity of NS and the scarcity of SOS2 mutation-related NS cases reported in the literature, it is difficult to provide appropriate genetic counseling. Several issues such as the best management technique and optimal NT cutoff have been discussed. In addition, in general, the fine balance between the advantages of an early prenatal diagnosis and the challenge of determining if the detected gene variant is pathogenic and, primarily, the stress of the counselees when providing a genetic counseling with limited information on the prenatal phenotype have been discussed. A prenatal path comprising examinations and multidisciplinary counseling is essential to support couples in a shared decision-making process.


Assuntos
Diagnóstico Precoce , Predisposição Genética para Doença , Síndrome de Noonan/diagnóstico , Proteínas Son Of Sevenless/genética , Feminino , Feto/diagnóstico por imagem , Feto/patologia , Aconselhamento Genético , Humanos , Masculino , Mutação de Sentido Incorreto , Síndrome de Noonan/diagnóstico por imagem , Síndrome de Noonan/genética , Síndrome de Noonan/patologia , Linhagem , Diagnóstico Pré-Natal
6.
Medicina (Kaunas) ; 57(12)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34946295

RESUMO

Background: Cleidocranial dysplasia (CCD) is a rare, autosomal dominant skeletal dysplasia with a prevalence of one per million births. The main causes of CCD are mutations in the core-binding factor alpha-1 (CBFA1) or runt-related transcription factor-2 (RUNX2), located at the 6p21 chromosomal region. RUNX2 plays important roles in osteoblast differentiation, chondrocyte proliferation and differentiation, and tooth formation. The disease is characterized by clavicular aplasia or hypoplasia, Wormian bones, delayed closure of cranial suture, brachycephalic head, maxillary deficiency, retention of primary teeth, inclusion of permanent teeth, and multiple supernumerary teeth. Materials and Methods: A 22-year-old girl suffering from cleidocranial dysplasia with short stature, narrow shoulders, craniofacial manifestations (short face, broad forehead, etc.) and dental anomalies (different lower dental elements under eruption, supernumerary and impacted multiple teeth, etc.) was examined at our service (Complex Operative Unit of Odontostomatology of Policlinico of Bari). RX Orthopantomography (OPG) and cone beam computed tomography (CBCT) were requested to better assess the position of the supernumerary teeth and their relationships with others and to evaluate the bone tissue. Results: Under eruption was probably caused by dental interferences with supernumerary teeth; hence, extractions of supernumerary upper canines and lower premolars were performed under general anaesthesia. Surgery outcome was excellent with good tissue healing and improvements in the therapeutic possibilities with future orthodontics. Conclusions: The objective of this article is to give an update about radiological, clinical, and molecular features of CCD and to alert the health team about the importance of establishing an early diagnosis and an appropriate treatment in these patients to prevent impacted teeth complications and to offer them a better quality of life.


Assuntos
Displasia Cleidocraniana , Dente Impactado , Dente Supranumerário , Adulto , Displasia Cleidocraniana/genética , Feminino , Humanos , Qualidade de Vida , Radiografia Panorâmica , Dente Impactado/diagnóstico por imagem , Dente Impactado/genética , Dente Impactado/cirurgia , Dente Supranumerário/diagnóstico por imagem , Dente Supranumerário/genética , Dente Supranumerário/cirurgia , Adulto Jovem
7.
Prenat Diagn ; 40(11): 1474-1481, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33034897

RESUMO

OBJECTIVE: To examine the incidence and type of chromosomal abnormalities in fetuses with first trimester ultrasound anomalies and a low-risk cfDNA test for common trisomies. METHODS: In 486 singleton pregnancies undergoing invasive testing after combined screening, a detailed first trimester ultrasound assessment was carried out and a maternal blood sample was sent for cfDNA analysis. Ultrasound and cfDNA data were analyzed in relation to fetal karyotype. RESULTS: Invasive testing demonstrated a chromosomal abnormality in 157 (32.3%) of 486 fetuses. In 348 cases with a low-risk cfDNA test for common trisomies, NT ≥ 3.5 mm and/or a major structural defect were observed in 92 (26.4%) fetuses. A chromosomal abnormality was found in 17 (18.5%; 95%CI 10.55-26.41) of these pregnancies, including 1 (1.1%) case of trisomy 21 and 16 (17.4%) fetuses with abnormalities different from common trisomies. The respective incidence in the 256 cases with a low-risk cfDNA test result and no ultrasound anomalies was 2.3% (95% CI 0.49-4.20; n = 6). CONCLUSIONS: In fetuses with first trimester ultrasound anomalies and a low-risk cfDNA result for trisomy 21, 18 and 13, diagnostic testing should be offered with the main objective to detect chromosomal abnormalities beyond common trisomies.


Assuntos
Aberrações Cromossômicas/estatística & dados numéricos , Anormalidades Congênitas/genética , Medição da Translucência Nucal , Adulto , Ácidos Nucleicos Livres/análise , Anormalidades Congênitas/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Primeiro Trimestre da Gravidez , Estudos Prospectivos , Trissomia/diagnóstico , Adulto Jovem
8.
Clin Genet ; 95(1): 165-171, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30288735

RESUMO

Biallelic exostosin-2 (EXT2) pathogenic variants have been described as the cause of the Seizures-Scoliosis-Macrocephaly syndrome (OMIM 616682) characterized by intellectual disability, facial dysmorphisms and seizures. More recently, it has been proposed to rename this disorder with the acronym AREXT2 (autosomal recessive EXT2-related syndrome). Here, we report the third family affected by AREXT2 syndrome, harboring compound missense variants in EXT2, p.Asp227Asn, and p.Tyr608Cys. In addition, our patients developed multiple exostoses, which were not observed in the previously described families. AREXT2 syndrome can be considered as a multiorgan Congenital Disorder of Glycosylation caused by a significant, but non-lethal, decrease in EXT2 expression, thereby affecting the synthesis of the heparan sulfate proteoglycans, which is relevant in many physiological processes. Our finding expands the clinical and molecular spectrum of the AREXT2 syndrome and suggests a possible genotype/phenotype correlation in the development of the exostoses.


Assuntos
Exostose Múltipla Hereditária/genética , Deficiência Intelectual/genética , N-Acetilglucosaminiltransferases/genética , Convulsões/genética , Adulto , Ecocardiografia , Exostose Múltipla Hereditária/diagnóstico por imagem , Exostose Múltipla Hereditária/fisiopatologia , Feminino , Predisposição Genética para Doença , Humanos , Lactente , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/fisiopatologia , Masculino , Mutação de Sentido Incorreto/genética , Linhagem , Convulsões/diagnóstico por imagem , Convulsões/fisiopatologia , Adulto Jovem
9.
Int J Mol Sci ; 18(6)2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28545230

RESUMO

The stromal vascular cell fraction (SVF) of visceral and subcutaneous adipose tissue (VAT and SAT) has increasingly come into focus in stem cell research, since these compartments represent a rich source of multipotent adipose-derived stem cells (ASCs). ASCs exhibit a self-renewal potential and differentiation capacity. Our aim was to study the different expression of the embryonic stem cell markers NANOG (homeobox protein NANOG), SOX2 (SRY (sex determining region Y)-box 2) and OCT4 (octamer-binding transcription factor 4) and to evaluate if there exists a hierarchal role in this network in ASCs derived from both SAT and VAT. ASCs were isolated from SAT and VAT biopsies of 72 consenting patients (23 men, 47 women; age 45 ± 10; BMI between 25 ± 5 and 30 ± 5 range) undergoing elective open-abdominal surgery. Sphere-forming capability was evaluated by plating cells in low adhesion plastic. Stem cell markers CD90, CD105, CD29, CD31, CD45 and CD146 were analyzed by flow cytometry, and the stem cell transcription factors NANOG, SOX2 and OCT4 were detected by immunoblotting and real-time PCR. NANOG, SOX2 and OCT4 interplay was explored by gene silencing. ASCs from VAT and SAT confirmed their mesenchymal stem cell (MSC) phenotype expressing the specific MSC markers CD90, CD105, NANOG, SOX2 and OCT4. NANOG silencing induced a significant OCT4 (70 ± 0.05%) and SOX2 (75 ± 0.03%) downregulation, whereas SOX2 silencing did not affect NANOG gene expression. Adipose tissue is an important source of MSC, and siRNA experiments endorse a hierarchical role of NANOG in the complex transcription network that regulates pluripotency.


Assuntos
Tecido Adiposo/citologia , Proteína Homeobox Nanog/metabolismo , Adulto , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína Homeobox Nanog/genética , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo
10.
Am J Med Genet A ; 170(7): 1884-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27148860

RESUMO

Chromosome 14q11-q22 deletion syndrome (OMIM 613457) is a rare genomic disorder whose associated phenotype is heterogeneous, depending on the size, and, mostly, on the deleted region. We report the clinical and molecular characterization of a female newborn, whose phenotype was characterized by poor growth, dysmorphic facial features, subclinical hypothyroidism, and mild reduction of CD3CD8 Lymphocytes with increased CD4/CD8 ratio. By array-CGH, we identified a 4.08 de novo interstitial deletion of the 14q13.2q21.1 region, which includes 16 OMIM genes.Our patient phenotype is compared with other published cases, for a better classification of the 14q11-q22 deletion syndrome. We demonstrated that the 14q13.2q21.1 deletion, which encompasses NKX2-1, but not FOXG1 gene and HPE8 region, identifies a well defined, more benign, microdeletion syndrome. This report confirms that an early identification with accurate characterization of the genomic disorders is of great relevance, enabling proper genetic counseling of the reproductive risk, as well as disease prognosis, and patient management. © 2016 Wiley Periodicals, Inc.


Assuntos
Deleção Cromossômica , Fatores de Transcrição Forkhead/genética , Hipotireoidismo/genética , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Cromossomos Humanos Par 14/genética , Hibridização Genômica Comparativa , Face/fisiopatologia , Feminino , Humanos , Hipotireoidismo/fisiopatologia , Hibridização in Situ Fluorescente , Recém-Nascido , Linfócitos/patologia , Masculino , Fenótipo , Fator Nuclear 1 de Tireoide
11.
Biochim Biophys Acta ; 1843(4): 675-84, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24389246

RESUMO

A study is presented on the expression of mitochondrial oxidative phosphorylation complexes in exponentially growing and serum-starved, quiescent human fibroblast cultures. The functional levels of respiratory complexes I and III and complex V (adenosine triphosphate (ATP) synthase) were found to be severely depressed in serum-starved fibroblasts. The depression of oxidative phosphorylation system (OXPHOS) complexes was associated with reduced levels of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and the down-stream nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factors (TFAM). In serum-starved fibroblasts decrease of the catalytic activity of AMP cyclic dependent protein kinase (PKA) and phosphorylation of cAMP response element-binding protein (CREB), the transcription coactivator of the PGC-1α gene, was found. Hydroxytyrosol prevented the decline in the expression of the PGC-1α transcription cascade of OXPHOS complexes in serum-starved fibroblast cultures. The positive effect of HT was associated with activation of PKA and CREB phosphorylation. These results show involvement of PKA, CREB and PGC-1α in the regulation of OXPHOS in cell transition from the replicating to the quiescent state.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/biossíntese , Mitocôndrias/enzimologia , Fosforilação Oxidativa/efeitos dos fármacos , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Complexos de ATP Sintetase/genética , Trifosfato de Adenosina/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Complexo I de Transporte de Elétrons/genética , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Mitocôndrias/metabolismo , Fator 1 Nuclear Respiratório/metabolismo , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/farmacologia , Transdução de Sinais/efeitos dos fármacos
12.
Am J Physiol Gastrointest Liver Physiol ; 309(10): G826-40, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26336926

RESUMO

The p66Shc protein mediates oxidative stress-related injury in multiple tissues. Steatohepatitis is characterized by enhanced oxidative stress-mediated cell damage. The role of p66Shc in redox signaling was investigated in human liver cells and alcoholic steatohepatitis. HepG2 cells with overexpression of wild-type or mutant p66Shc, with Ser36 replacement by Ala, were obtained through infection with recombinant adenoviruses. Reactive oxygen species and oxidation-dependent DNA damage were assessed by measuring dihydroethidium oxidation and 8-hydroxy-2'-deoxyguanosine accumulation into DNA, respectively. mRNA and protein levels of signaling intermediates were evaluated in HepG2 cells and liver biopsies from control and alcoholic steatohepatitis subjects. Exposure to H2O2 increased reactive oxygen species and phosphorylation of p66Shc on Ser36 in HepG2 cells. Overexpression of p66Shc promoted reactive oxygen species synthesis and oxidation-dependent DNA damage, which were further enhanced by H2O2. p66Shc activation also resulted in increased Erk-1/2, Akt, and FoxO3a phosphorylation. Blocking of Erk-1/2 activation inhibited p66Shc phosphorylation on Ser36. Increased p66Shc expression was associated with reduced mRNA levels of antioxidant molecules, such as NF-E2-related factor 2 and its target genes. In contrast, overexpression of the phosphorylation defective p66Shc Ala36 mutant inhibited p66Shc signaling, enhanced antioxidant genes, and suppressed reactive oxygen species and oxidation-dependent DNA damage. Increased p66Shc protein levels and Akt phosphorylation were observed in liver biopsies from alcoholic steatohepatitis compared with control subjects. In human alcoholic steatohepatitis, increased hepatocyte p66Shc protein levels may enhance susceptibility to DNA damage by oxidative stress by promoting reactive oxygen species synthesis and repressing antioxidant pathways.


Assuntos
Dano ao DNA , Fígado Gorduroso Alcoólico/metabolismo , Hepatócitos/metabolismo , Oxirredução , Estresse Oxidativo , Proteínas Adaptadoras da Sinalização Shc , Técnicas de Cultura de Células , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Humanos , Proteína Oncogênica v-akt/metabolismo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Proteínas Adaptadoras da Sinalização Shc/genética , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Transdução de Sinais , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src
13.
Curr Diab Rep ; 15(3): 12, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25687500

RESUMO

Lipodystrophies are a genetically heterogeneous group of disorders characterized by loss of subcutaneous adipose tissue and metabolic dysfunction, including insulin resistance, increased levels of free fatty acids, abnormal adipocytokine secretion, and ectopic fat deposition, which are also observed in patients with visceral obesity and/or type 2 diabetes mellitus. Pathophysiological, biochemical, and genetic studies suggest that impairment in multiple adipose tissue functions, including adipocyte maturation, lipid storage, formation and/or maintenance of the lipid droplet, membrane composition, DNA repair efficiency, and insulin signaling, results in severe metabolic and endocrine consequences, ultimately leading to specific lipodystrophic phenotypes. In this review, recent evidences on the causes and metabolic processes of lipodystrophies will be presented, proposing a disease model that could be potentially informative for better understanding of common metabolic diseases in humans, including obesity, metabolic syndrome, and type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Lipodistrofia/complicações , Tecido Adiposo/patologia , Estudos de Associação Genética , Humanos , Lipodistrofia/classificação , Lipodistrofia/tratamento farmacológico , Lipodistrofia/genética , Mitocôndrias/metabolismo
14.
Nat Genet ; 37(11): 1258-63, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16227998

RESUMO

We identified 11 human pedigrees with dominantly inherited hemolytic anemias in both the hereditary stomatocytosis and spherocytosis classes. Affected individuals in these families had an increase in membrane permeability to Na and K that is particularly marked at 0 degrees C. We found that disease in these pedigrees was associated with a series of single amino-acid substitutions in the intramembrane domain of the erythrocyte band 3 anion exchanger, AE1. Anion movements were reduced in the abnormal red cells. The 'leak' cation fluxes were inhibited by SITS, dipyridamole and NS1652, chemically diverse inhibitors of band 3. Expression of the mutated genes in Xenopus laevis oocytes induced abnormal Na and K fluxes in the oocytes, and the induced Cl transport was low. These data are consistent with the suggestion that the substitutions convert the protein from an anion exchanger into an unregulated cation channel.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/genética , Cátions/metabolismo , Cloretos/metabolismo , Eritrócitos/metabolismo , Potássio/metabolismo , Sódio/metabolismo , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-dissulfônico/farmacologia , Substituição de Aminoácidos , Anemia Hemolítica/genética , Anemia Hemolítica/metabolismo , Animais , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Benzoatos/farmacologia , Transporte Biológico , Permeabilidade da Membrana Celular , Dipiridamol/farmacologia , Humanos , Dados de Sequência Molecular , Oócitos/citologia , Oócitos/metabolismo , Linhagem , Compostos de Fenilureia/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Estrutura Terciária de Proteína , RNA/metabolismo , Esferocitose Hereditária/genética , Xenopus laevis
15.
Genes (Basel) ; 15(8)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39202376

RESUMO

Cardiac involvement is a major feature of RASopathies, a group of phenotypically overlapping syndromes caused by germline mutations in genes encoding components of the RAS/MAPK (mitogen-activated protein kinase) signaling pathway. In particular, Noonan syndrome (NS) is associated with a wide spectrum of cardiac pathologies ranging from congenital heart disease (CHD), present in approximately 80% of patients, to hypertrophic cardiomyopathy (HCM), observed in approximately 20% of patients. Genotype-cardiac phenotype correlations are frequently described, and they are useful indicators in predicting the prognosis concerning cardiac disease over the lifetime. The aim of this review is to clarify the molecular mechanisms underlying the development of cardiac diseases associated particularly with NS, and to discuss the main morphological and clinical characteristics of the two most frequent cardiac disorders, namely pulmonary valve stenosis (PVS) and HCM. We will also report the genotype-phenotype correlation and its implications for prognosis and treatment. Knowing the molecular mechanisms responsible for the genotype-phenotype correlation is key to developing possible targeted therapies. We will briefly address the first experiences of targeted HCM treatment using RAS/MAPK pathway inhibitors.


Assuntos
Síndrome de Noonan , Humanos , Síndrome de Noonan/genética , Síndrome de Noonan/patologia , Fenótipo , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/patologia , Proteínas ras/genética , Proteínas ras/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Estenose da Valva Pulmonar/genética , Estenose da Valva Pulmonar/patologia , Estudos de Associação Genética , Cardiopatias Congênitas/genética , Cardiopatias Congênitas/patologia , Mutação
16.
Genes (Basel) ; 14(12)2023 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-38137016

RESUMO

Large-scale genomic structural variations can have significant clinical implications, depending on the specific altered genomic region. Briefly, 2q37 microdeletion syndrome is a prevalent subtelomeric deletion disorder characterized by variable-sized deletions. Affected patients exhibit a wide range of clinical manifestations, including short stature, facial dysmorphism, and features of autism spectrum disorder, among others. Conversely, isolated duplications of proximal chromosome 2q are rare and lack a distinct phenotype. In this report, we provide an extensive molecular analysis of a 15-day-old newborn referred for syndromic features. Our analysis reveals an 8.5 Mb microdeletion at 2q37.1, which extends to the telomere, in conjunction with an 8.6 Mb interstitial microduplication at 2q34q36.1. Our findings underscore the prominence of 2q37 terminal deletions as commonly reported genomic anomalies. We compare our patient's phenotype with previously reported cases in the literature to contribute to a more refined classification of 2q37 microdeletion syndrome and assess the potential impact of 2q34q36.1 microduplication. We also investigate multiple hypotheses to clarify the genetic mechanisms responsible for the observed genomic rearrangement.


Assuntos
Transtorno do Espectro Autista , Deficiência Intelectual , Recém-Nascido , Humanos , Deleção Cromossômica , Deficiência Intelectual/genética , Transtorno do Espectro Autista/genética , Estruturas Cromossômicas , Telômero
17.
Nat Commun ; 14(1): 1475, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36928426

RESUMO

Split-Hand/Foot Malformation type 3 (SHFM3) is a congenital limb malformation associated with tandem duplications at the LBX1/FGF8 locus. Yet, the disease patho-mechanism remains unsolved. Here we investigate the functional consequences of SHFM3-associated rearrangements on chromatin conformation and gene expression in vivo in transgenic mice. We show that the Lbx1/Fgf8 locus consists of two separate, but interacting, regulatory domains. Re-engineering of a SHFM3-associated duplication and a newly reported inversion in mice results in restructuring of the chromatin architecture. This leads to ectopic activation of the Lbx1 and Btrc genes in the apical ectodermal ridge (AER) in an Fgf8-like pattern induced by AER-specific enhancers of Fgf8. We provide evidence that the SHFM3 phenotype is the result of a combinatorial effect on gene misexpression in the developing limb. Our results reveal insights into the molecular mechanism underlying SHFM3 and provide conceptual framework for how genomic rearrangements can cause gene misexpression and disease.


Assuntos
Fator 8 de Crescimento de Fibroblasto , Rearranjo Gênico , Deformidades Congênitas dos Membros , Animais , Camundongos , Expressão Gênica , Proteínas de Homeodomínio/genética , Deformidades Congênitas dos Membros/genética , Fenótipo , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/genética
18.
Expert Rev Mol Med ; 14: e19, 2012 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-23302474

RESUMO

Stem cells are unique cells exhibiting self-renewing properties and the potential to differentiate into multiple specialised cell types. Totipotent or pluripotent stem cells are generally abundant in embryonic or fetal tissues, but the use of discarded embryos as sources of these cells raises challenging ethical problems. Adult stem cells can also differentiate into a wide variety of cell types. In particular, adult adipose tissue contains a pool of abundant and accessible multipotent stem cells, designated as adipose-derived stem cells (ASCs), that are able to replicate as undifferentiated cells, to develop as mature adipocytes and to differentiate into multiple other cell types along the mesenchymal lineage, including chondrocytes, myocytes and osteocytes, and also into cells of endodermal and neuroectodermal origin, including beta-cells and neurons, respectively. An impairment in the differentiation potential and biological functions of ASCs may contribute to the development of obesity and related comorbidities. In this review, we summarise different aspects of the ASCs with special reference to the isolation and characterisation of these cell populations, their relation to the biochemical features of the adipose tissue depot of origin and to the metabolic characteristics of the donor subject and discuss some prospective therapeutic applications.


Assuntos
Adipócitos/citologia , Tecido Adiposo/citologia , Doenças Metabólicas/etiologia , Obesidade/etiologia , Células-Tronco/citologia , Adipócitos/metabolismo , Diferenciação Celular , Humanos , Doenças Metabólicas/terapia , Obesidade/terapia , Transplante de Células-Tronco , Células-Tronco/metabolismo
19.
Brain Sci ; 12(5)2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35625000

RESUMO

Horizontal gaze palsy with progressive scoliosis (HGPPS) is a rare congenital disease characterized by the absence of horizontal gaze movements, progressive scoliosis, and typical brain, cerebellum, and medullary malformations. Here we describe a pediatric HGPPS case with overlapping epilepsy and learning difficulties. A 6-year-old girl was admitted to the University Hospital of Bari for the onset of a tonic-clonic seizure. Electroencephalogram showed slow and sharp waves on the right side with the tendency to diffuse. Brain magnetic resonance imaging demonstrated malformations compatible with HGPPS. Ophthalmological and orthopedic evaluations confirmed conjugate horizontal gaze palsy and mild thoracolumbar scoliosis. Neuropsychological assessment attested normal intelligence but serious difficulties in reading and writing. In spite of neuroradiological malformations, visual difficulties, and spinal deformities, literature data are limited about any coexisting neurocognitive HGPPS symptoms. Literature data regarding such topics are very limited. If, on the one hand, the coexistence of such symptoms can be interpreted as occasional, it could support the idea that they could fall within a spectrum of HGPPS anomalies. In addition to the standard investigations, the activation of specific neuropsychological assessment programs could help interventions improve the specialist care and the quality of life of HGPPS patients.

20.
Front Oncol ; 12: 966063, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992853

RESUMO

BRCA-1 associated protein 1 (BAP1) tumour predisposition syndrome (TPDS) is a hereditary condition characterised by germline mutation of the tumour suppressor BAP1. This disorder is associated with the development of various benign and malignant tumours, mainly involving the skin, eyes, kidneys, and mesothelium. In this article, we report the case of a man recruited through the Apulia (Southern Italy) Mesothelioma Regional Operational Centre of the National Register of Mesotheliomas, who suffered from uveal melanoma, renal cancer, and mesothelioma, and a familial cluster of BAP1 germline mutations demonstrated by molecular analyses. The family members of the proband developed multiple malignancies. As tumours arising in this context have specific peculiarities in terms of clinical behaviour, identification of this condition through appropriate genetic counselling should be considered for adequate primary, secondary, and tertiary prevention measures for offspring.

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