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1.
J Surg Res ; 257: 56-68, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32818785

RESUMO

BACKGROUND: Burn injuries (BIs) due to scalding are one of the most common accidents among children. BIs greater than 40% of total body surface area are considered extensive and result in local and systemic response. We sought to assess morphological and myogenic mechanisms through both short- and long-term intensive insulin therapies that affect the skeletal muscle after extensive skin BI in young rats. MATERIALS AND METHODS: Wistar rats aged 21 d were distributed into four groups: control (C), control with insulin (C + I), scald burn injury (SI), and SI with insulin (SI + I). The SI groups were submitted to a 45% total body surface area burn, and the C + I and SI + I groups received insulin (5 UI/Kg/d) for 4 or 14 d. Glucose tolerance and the homeostatic model assessment of insulin resistance index were determined. Gastrocnemius muscles were analyzed for histopathological, morphometric, and immunohistochemical myogenic parameters (Pax7, MyoD, and MyoG); in addition, the expression of genes related to muscle atrophy (MuRF1 and MAFbx) and its regulation (IGF-1) were also assessed. RESULTS: Short-term treatment with insulin favored muscle regeneration by primary myogenesis and decreased muscle atrophy in animals with BIs, whereas the long-term treatment modulated myogenesis by increasing the MyoD protein. Both treatments improved histopathological parameters and secondary myogenesis by increasing the MyoG protein. CONCLUSIONS: Treatment with insulin benefits myogenic parameters during regeneration and modulates MuRF1, an important mediator of muscle atrophy.


Assuntos
Queimaduras/complicações , Insulina/administração & dosagem , Desenvolvimento Muscular/efeitos dos fármacos , Atrofia Muscular/prevenção & controle , Animais , Glicemia/análise , Superfície Corporal , Queimaduras/patologia , Queimaduras/fisiopatologia , Expressão Gênica/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/genética , Masculino , Proteínas Musculares/genética , Músculo Esquelético/química , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Atrofia Muscular/etiologia , Atrofia Muscular/genética , Proteína MyoD/análise , Miogenina/análise , Fatores de Transcrição Box Pareados/análise , Ratos , Ratos Wistar , Proteínas Ligases SKP Culina F-Box/genética , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genética
2.
Sci Total Environ ; 758: 143954, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33333305

RESUMO

Protein carbonylation is an irreversible oxidative modification that has been associated with a decrease in the quality and nutritional value of products of animal origin. Generally, the carbonylation is attributed to processes of slaughter, processing, and cold storage of products. However, in vitro studies have shown that fluoroquinolone and organophosphate pesticides residues at their maximum residue limits (MRL) can promote carbonylation of animal proteins. Though, this effect on in vivo conditions has not yet been evaluated. Thus, Eisenia fetida was chosen as a model to assay their oxidant effect. For this, adult earthworms were exposed to artificial soil contaminated with ciprofloxacin, danofloxacin, fenthion, and diazinon at three concentrations (0.5, 1.0, and 1.5 MRL) for 28 days. Then, these were purged and sacrificed to obtain the muscle region between the anus and preclitellum. The muscle samples were cold macerated to obtain muscle proteins, which were used for protein quantification, determination of carbonyl levels, and carbonyl protein profiles employing Bradford, Dot-blot, and Western blot assays, respectively. The results showed that at each concentration assayed, all pollutants induced significant carbonylation respect to control (p < 0.05). Additionally, mass spectrometry-based analysis (MALDI-TOF/TOF) identified actin as the protein most susceptible to carbonylation promoted by these substances. Therefore, these findings show for the first time the oxidant power of fluoroquinolones and organophosphates pesticides at MRLs concentrations on muscle proteins under in vivo conditions. Fact causes concern due to the homology of muscle proteins in eukaryotes, which allow to hypothesize that this effect could also be experienced by proteins from food-producing animals in the same way that observed in in vitro studies.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Antibacterianos/toxicidade , Fluoroquinolonas , Proteínas Musculares , Solo , Poluentes do Solo/toxicidade
3.
Food Chem ; 337: 127993, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920273

RESUMO

The effect of pH and ionic strength (µ) on the extraction capacity of myofibrillar proteins from Jumbo squid mantle muscle along with the addition of isoascorbic acid (IA) in its gel-forming ability (GFA) were evaluated. The results indicate that µ had a greater impact (p < 0.05) than pH on the extraction of muscle myofibrillar proteins. The effectiveness of IA, as the precursor of dehydro-isoascorbic acid (DIA), on the oxidation of sulfhydryl groups (-SH) to disulfide bonds (-SS-) of extracted proteins at 0.6 µ was also evaluated. During the sol-gel transition the -SH groups initially present in the protein system decreased (p < 0.05) due to the combined effect of heat treatment (90 °C/30 min) and the addition of IA; however, the oxidative effect of IA reduced (p < 0.05) the GFA of Jumbo squid muscle proteins. Results also indicated that NaCl at 2.8% rather than at 2.5% during gel preparation significantly (p < 0.05) improves its GFA.


Assuntos
Ácido Ascórbico/química , Decapodiformes/química , Géis/química , Proteínas Musculares/química , Músculos/química , Animais , Dissulfetos/química , Concentração de Íons de Hidrogênio , Concentração Osmolar , Solubilidade
4.
Food Chem ; 338: 128029, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32932089

RESUMO

Peptides derived from whole proteins in beef tenderloin (M. psoas major, PM) and striploin (M. longissimus lumborum, LL) associated with meat quality and muscle fiber composition were identified and quantified during 21 days of aging. Peptide quantification revealed 40-43 proteins to be significantly degraded during all aging time, and these were mostly sarcoplasmic proteins. Cooking loss of both muscles was not changed by aging (P > 0.05), whereas Warner-Bratzler shear force and meat color were affected by aging. Sensory tenderness increased in PM after 14 days of aging (P < 0.05). PM had a higher type I fiber content, whereas LL had a higher type IIX fiber content (P < 0.05), resulting in differences in proteolysis during all aging periods tested. These findings improve our understanding of different biochemical and physicochemical changes in aged meat according to the muscle type.


Assuntos
Armazenamento de Alimentos/métodos , Carne/análise , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Peptídeos/metabolismo , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Temperatura Baixa , Cor , Qualidade dos Alimentos , Peptídeos/análise , Mapas de Interação de Proteínas , Espectrometria de Massas em Tandem , Fatores de Tempo
5.
Food Chem ; 338: 128138, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33091978

RESUMO

The aim of this study was to investigate the effects of different curing methods on protein structure, protein and lipid oxidation, lypolysis and volatile compounds in duck breast meat. The results showed that compared to static brining and pulsed pressure salting, the vacuum tumbling curing significantly decreased the oxidation of proteins and lipids, and the surface hydrophobicity of proteins, increased α-helix structure but decreased the proportion of ß-sheet, and increased actomyosin dissociation, liplysis and the free fatty acid content in meat. Meanwhile, vacuum tumbling curing decreased the amount of volatile flavor compounds, hexanal, 2,3-octanone, and off-flavor compounds 1-octen-3-ol and 1-hexanol. This study suggests that concerns on healthiness and the sensory quality of processed meat products should be paid in the selection of curing methods and vacuum tumbling curing is superior in terms of both aspects.


Assuntos
Patos , Ácidos Graxos não Esterificados/análise , Manipulação de Alimentos/métodos , Carne/análise , Proteínas Musculares/análise , Compostos Orgânicos Voláteis/análise , Animais , Humanos , Lipídeos/análise , Oxirredução , Paladar
6.
Food Chem ; 338: 128146, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33091990

RESUMO

Myofibrillar protein isolated from beef muscles were treated with 3 phosphates (Sodium Hexametaphosphate, sodium tripolyphosphate, sodium pyrophosphate) with different concentrations of 0.3%, 0.6%, 0.9%, 1.2% respectively. Protein solubility, surface hydrophobicity and reactive sulfhydryl group was determined. Atomic force microscopy was used to observe the microscopic protein surface. SDS-PAGE was carried out to determine the proteolysis of myofibrillar protein. The solubility and surface hydrophobic bond of myofibrillar protein was highly increased and the diameter decreased by SHMP, TSPP, STPP. Reactive sulfhydryl groups increased after SHMP addition, but slightly decreased in STPP and TSPP treated MP. TSPP and STPP had the same effect on myofibrillar microstructure and was different from SHMP. Three phosphates all caused MP unfolding. The MP gel complexity was increased, and roughness was decreased after phosphates addition, indicating phosphates helped to construct a more ordered and smoother gel microcosmic surface.


Assuntos
Difosfatos/química , Microscopia de Força Atômica , Proteínas Musculares/química , Fosfatos/química , Polifosfatos/química , Carne Vermelha , Animais , Bovinos , Interações Hidrofóbicas e Hidrofílicas , Solubilidade
7.
Food Chem ; 339: 127941, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152853

RESUMO

The effect and mechanism of myofibrillar protein (MP) gelation influenced by konjac glucomannan (KG) addition were studied. The KG addition significantly improved gel strength and water holding capability (WHC) of MP-KG composite gel, but it had additive limitation at 1.0%. The SEM showed that KG (<1.0%) reduced the appearance of moisture channels and promoted the formation of an integral MP gel network. Raman spectroscopy showed that KG addition (<1.0%) promoted the protein unfolding and the interaction of hydrophobic groups during thermal processing. However, the KG (>1.0%) would form continuous viscous hydrogel and interpenetrate with the MP solution, which hindered the interaction of hydrophobic groups during thermal process, and the MP formed a loose and degraded final structure. Hence, MP gels produced with the addition of KG underwent a transformation from a loose structure to a compact structure to an unaggregated structure, which was influenced by moisture stability and phase separation behavior.


Assuntos
Mananas/química , Proteínas Musculares/química , Géis , Interações Hidrofóbicas e Hidrofílicas , Estabilidade Proteica , Desdobramento de Proteína , Reologia , Água/química
8.
Nat Commun ; 11(1): 4913, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004813

RESUMO

Reprograming of proline metabolism is critical for tumor growth. Here we show that PINCH-1 is highly expressed in lung adenocarcinoma and promotes proline synthesis through regulation of mitochondrial dynamics. Knockout (KO) of PINCH-1 increases dynamin-related protein 1 (DRP1) expression and mitochondrial fragmentation, which suppresses kindlin-2 mitochondrial translocation and interaction with pyrroline-5-carboxylate reductase 1 (PYCR1), resulting in inhibition of proline synthesis and cell proliferation. Depletion of DRP1 reverses PINCH-1 deficiency-induced defects on mitochondrial dynamics, proline synthesis and cell proliferation. Furthermore, overexpression of PYCR1 in PINCH-1 KO cells restores proline synthesis and cell proliferation, and suppresses DRP1 expression and mitochondrial fragmentation. Finally, ablation of PINCH-1 from lung adenocarcinoma in mouse increases DRP1 expression and inhibits PYCR1 expression, proline synthesis, fibrosis and tumor growth. Our results identify a signaling axis consisting of PINCH-1, DRP1 and PYCR1 that regulates mitochondrial dynamics and proline synthesis, and suggest an attractive strategy for alleviation of tumor growth.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenocarcinoma de Pulmão/patologia , Proteínas com Domínio LIM/metabolismo , Neoplasias Pulmonares/patologia , Proteínas de Membrana/metabolismo , Células A549 , Proteínas Adaptadoras de Transdução de Sinal/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Proliferação de Células/genética , Proteínas do Citoesqueleto/metabolismo , Modelos Animais de Doenças , Dinaminas/metabolismo , Feminino , Técnicas de Inativação de Genes , Humanos , Proteínas com Domínio LIM/genética , Pulmão/citologia , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Proteínas Musculares/metabolismo , Proteínas de Neoplasias/metabolismo , Prolina/biossíntese , Proteínas Proto-Oncogênicas p21(ras)/genética , Pirrolina Carboxilato Redutases/metabolismo , Análise de Sobrevida
9.
Sports Health ; 12(6): 579-586, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866081

RESUMO

CONTEXT: Distinct from the muscle atrophy that develops from inactivity or disuse, atrophy that occurs after traumatic joint injury continues despite the patient being actively engaged in exercise. Recognizing the multitude of factors and cascade of events that are present and negatively influence the regulation of muscle mass after traumatic joint injury will likely enable clinicians to design more effective treatment strategies. To provide sports medicine practitioners with the best strategies to optimize muscle mass, the purpose of this clinical review is to discuss the predominant mechanisms that control muscle atrophy for disuse and posttraumatic scenarios, and to highlight how they differ. EVIDENCE ACQUISITION: Articles that reported on disuse atrophy and muscle atrophy after traumatic joint injury were collected from peer-reviewed sources available on PubMed (2000 through December 2019). Search terms included the following: disuse muscle atrophy OR disuse muscle mass OR anterior cruciate ligament OR ACL AND mechanism OR muscle loss OR atrophy OR neurological disruption OR rehabilitation OR exercise. STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 5. RESULTS: We highlight that (1) muscle atrophy after traumatic joint injury is due to a broad range of atrophy-inducing factors that are resistant to standard resistance exercises and need to be effectively targeted with treatments and (2) neurological disruptions after traumatic joint injury uncouple the nervous system from muscle tissue, contributing to a more complex manifestation of muscle loss as well as degraded tissue quality. CONCLUSION: Atrophy occurring after traumatic joint injury is distinctly different from the muscle atrophy that develops from disuse and is likely due to the broad range of atrophy-inducing factors that are present after injury. Clinicians must challenge the standard prescriptive approach to combating muscle atrophy from simply prescribing physical activity to targeting the neurophysiological origins of muscle atrophy after traumatic joint injury.


Assuntos
Lesões do Ligamento Cruzado Anterior/complicações , Atrofia Muscular/etiologia , Lesões do Ligamento Cruzado Anterior/patologia , Lesões do Ligamento Cruzado Anterior/fisiopatologia , Citocinas/sangue , Exercício Físico/fisiologia , Humanos , Fibras Musculares Esqueléticas/fisiologia , Proteínas Musculares/biossíntese , Músculo Esquelético/inervação , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Miostatina/fisiologia , Proteólise , Células Satélites de Músculo Esquelético/fisiologia
10.
PLoS One ; 15(9): e0238441, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881965

RESUMO

Limb-girdle muscular dystrophy type 2B (LGMD2B) is caused by mutations in the dysferlin gene, resulting in non-functional dysferlin, a key protein found in muscle membrane. Treatment options available for patients are chiefly palliative in nature and focus on maintaining ambulation. Our hypothesis is that galectin-1 (Gal-1), a soluble carbohydrate binding protein, increases membrane repair capacity and myogenic potential of dysferlin-deficient muscle cells and muscle fibers. To test this hypothesis, we used recombinant human galectin-1 (rHsGal-1) to treat dysferlin-deficient models. We show that rHsGal-1 treatments of 48 h-72 h promotes myogenic maturation as indicated through improvements in size, myotube alignment, myoblast migration, and membrane repair capacity in dysferlin-deficient myotubes and myofibers. Furthermore, increased membrane repair capacity of dysferlin-deficient myotubes, independent of increased myogenic maturation is apparent and co-localizes on the membrane of myotubes after a brief 10min treatment with labeled rHsGal-1. We show the carbohydrate recognition domain of Gal-1 is necessary for observed membrane repair. Improvements in membrane repair after only a 10 min rHsGal-1treatment suggest mechanical stabilization of the membrane due to interaction with glycosylated membrane bound, ECM or yet to be identified ligands through the CDR domain of Gal-1. rHsGal-1 shows calcium-independent membrane repair in dysferlin-deficient and wild-type myotubes and myofibers. Together our novel results reveal Gal-1 mediates disease pathologies through both changes in integral myogenic protein expression and mechanical membrane stabilization.


Assuntos
Disferlina/genética , Galectina 1/farmacologia , Distrofia Muscular do Cíngulo dos Membros/terapia , Animais , Linhagem Celular , Modelos Animais de Doenças , Disferlina/metabolismo , Galectina 1/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Membranas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Desenvolvimento Muscular/genética , Fibras Musculares Esqueléticas/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Distrofia Muscular do Cíngulo dos Membros/metabolismo , Miofibrilas/metabolismo
11.
BMC Med Genet ; 21(1): 188, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32993534

RESUMO

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a genetic disorder mostly caused by sarcomeric gene mutations, but almost 10% of cases are attributed to inherited metabolic and neuromuscular disorders. First described in 2008 in an American-Italian family with scapuloperoneal myopathy, FHL1 gene encodes four-and-a-half LIM domains 1 proteins which are involved in sarcomere formation, assembly and biomechanical stress sensing both in cardiac and skeletal muscle, and its mutations are responsible for a large spectrum of neuromuscular disorders (mostly myopathies) and cardiac disease, represented by HCM, either isolated, or in conjunction with neurologic and skeletal muscle impairment. We thereby report a novel mutation variant in FHL1 structure, associated with HCM and type 6 Emery-Dreifuss muscular dystrophy (EDMD). CASE PRESENTATION: We describe the case of a 40 year old male patient, who was referred to our department for evaluation in the setting of NYHA II heart failure symptoms and was found to have HCM. The elevated muscular enzymes raised the suspicion of a neuromuscular disease. Rigid low spine and wasting of deltoidus, supraspinatus, infraspinatus and calf muscles were described by the neurological examination. Electromyography and muscle biopsy found evidence of chronic myopathy. Diagnosis work-up was completed by next-generation sequencing genetic testing which found a likely pathogenic mutation in the FHL1 gene (c.157-1G > A, hemizygous) involved in the development of X-linked EDMD type 6. CONCLUSION: This case report highlights the importance of multimodality diagnostic approach in a patient with a neuromuscular disorder and associated hypertrophic cardiomyopathy by identifying a novel mutation variant in FHL1 gene. Raising awareness of non-sarcomeric gene mutations which can lead to HCM is fundamental, because of diagnostic and clinical risk stratification challenges.


Assuntos
Cardiomiopatia Hipertrófica/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas com Domínio LIM/genética , Proteínas Musculares/genética , Doenças Musculares/genética , Mutação , Adulto , Cardiomiopatia Hipertrófica/diagnóstico , Saúde da Família , Feminino , Testes Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Linhagem
12.
PLoS One ; 15(9): e0239047, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941492

RESUMO

Muscle aging is accompanied by blunted muscle regeneration in response to injury and disuse. Oxidative stress likely underlies this diminished response, but muscle redox sensors that act in regeneration have not yet been characterized. Calmodulin contains multiple redox sensitive methionines whose oxidation alters the regulation of numerous cellular targets. We have used the CRISPR-Cas9 system to introduce a single amino acid substitution M109Q that mimics oxidation of methionine to methionine sulfoxide in one or both alleles of the CALM1 gene, one of three genes encoding the muscle regulatory protein calmodulin, in C2C12 mouse myoblasts. When signaled to undergo myogenesis, mutated myoblasts failed to differentiate into myotubes. Although early myogenic regulatory factors were present, cells with the CALM1 M109Q mutation in one or both alleles were unable to withdraw from the cell cycle and failed to express late myogenic factors. We have shown that a single oxidative modification to a redox-sensitive muscle regulatory protein can halt myogenesis, suggesting a molecular target for mitigating the impact of oxidative stress in age-related muscle degeneration.


Assuntos
Calmodulina/metabolismo , Desenvolvimento Muscular/fisiologia , Animais , Calmodulina/genética , Calmodulina/fisiologia , Diferenciação Celular/fisiologia , Camundongos , Fibras Musculares Esqueléticas/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Mioblastos/metabolismo , Oxirredução , Estresse Oxidativo/fisiologia
13.
PLoS One ; 15(9): e0238420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32931492

RESUMO

BACKGROUND: Patients diagnosed with Oral Floor Squamous Cell Carcinoma (OFSCC) face considerable challenges in physiology and psychology. This study explored prognostic signatures to predict prognosis in OFSCC through a detailed transcriptomic analysis. METHOD: We built an interactive competing endogenous RNA (ceRNA) network that included lncRNAs, miRNAs and mRNAs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to predict the gene functions and regulatory pathways of mRNAs. Least absolute shrinkage and selection operator algorithm (LASSO) analysis and Cox regression analysis were used to screen prognosis factors. The Kaplan-Meier method was used to analyze the survival rate of prognosis factors. Risk score was used to assess the reliability of the prediction model. RESULTS: A specific ceRNA network consisting of 56 mRNAs, 16 miRNAs and 31 lncRNAs was established. Three key genes (HOXC13, TGFBR3, KLHL40) and 4 clinical factors (age, gender, TNM, and clinical stage) were identified and effectively predicted the for survival time. The expression of a gene signature was validated in two external validation cohorts. The signature (areas under the curve of 3 and 5 years were 0.977 and 0.982, respectively) showed high prognostic accuracy in the complete TCGA cohort. CONCLUSIONS: Our study successfully developed an extensive ceRNA network for OFSCC and further identified a 3-mRNA and 4-clinical-factor signature, which may serve as a biomarker.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Neoplasias Bucais/genética , RNA Neoplásico/genética , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Bases de Dados de Ácidos Nucleicos , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Proteínas de Homeodomínio/genética , Humanos , Estimativa de Kaplan-Meier , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Soalho Bucal , Neoplasias Bucais/mortalidade , Proteínas Musculares/genética , Prognóstico , Proteoglicanas/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Fatores de Risco
14.
BMC Med Genet ; 21(1): 177, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887565

RESUMO

BACKGROUND: Keratoconus (KC) is usually bilateral, noninflammatory progressive corneal ectasia in which the cornea becomes progressively thin and conical, resulting in myopia, irregular astigmatism, and corneal scarring. METHODS: Eight families characterized by consanguineous marriages and/or multiple keratoconic individuals were examined genetically. Whole exome sequencing was done as trio or quadro per family. The output of the filtration procedure, based on minor allele frequency (MAF) less than 0.01 for homozygous variants and MAF equals 0 for heterozygous variants, is 22 missense variants. RESULTS: Based on the gene/protein function five candidate variants were highlighted in four families. Two variants were highlighted in one family within the genes MYOF and STX2, and one variant is highlighted in each of the other three families within the genes: COL6A5, ZNF676 and ZNF765. CONCLUSION: This study is one of the very rare that highlights genetic variants in association with KC.


Assuntos
Predisposição Genética para Doença/genética , Ceratocone/genética , Mutação , Sequenciamento Completo do Exoma/métodos , Proteínas de Ligação ao Cálcio/genética , Colágeno Tipo VI/genética , Consanguinidade , Proteínas de Ligação a DNA/genética , Saúde da Família , Feminino , Humanos , Jordânia , Ceratocone/diagnóstico , Masculino , Proteínas de Membrana/genética , Proteínas Musculares/genética , Linhagem , Sintaxina 1/genética
15.
Int Heart J ; 61(5): 1079-1083, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32879264

RESUMO

A Japanese girl with polycystic kidney disease (PKD) developed normally, but at 8 months of age, she was hospitalized for acute onset dyspnea. On the day after admission to hospital, her general condition suddenly became worse. An echocardiogram showed left ventricular dilatation with thin walls, severe mitral valve regurgitation, and a reduced ejection fraction. She died of acute cardiac failure 3 hours after the sudden change. Postmortem analysis with light microscopy showed disarray of cardiomyocytes without obvious infiltration of lymphocytes, and we diagnosed her heart failure as idiopathic dilated cardiomyopathy (DCM). Clinical exome sequencing showed compound heterozygous variants in JPH2 (p.T237A/p.I414L) and a heterozygous nonsense mutation in PKD1 (p.Q4193*). To date, several variants in the JPH2 gene have been reported to be pathogenic for adult-onset hypertrophic cardiomyopathy or DCM in an autosomal dominant manner and infantile-onset DCM in an autosomal recessive manner. Additionally, autosomal dominant polycystic kidney disease is a systemic disease associated with several extrarenal manifestations, such as cardiomyopathy. Here we report a sudden infant death case of DCM and discuss the genetic variants of DCM and PKD.


Assuntos
Cardiomiopatia Dilatada/genética , Proteínas de Membrana/genética , Proteínas Musculares/genética , Rim Policístico Autossômico Dominante/genética , Canais de Cátion TRPP/genética , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/patologia , Morte Súbita Cardíaca/etiologia , Evolução Fatal , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/etiologia , Heterozigoto , Humanos , Lactente , Insuficiência da Valva Mitral/etiologia , Miocárdio/patologia , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue
16.
PLoS Biol ; 18(9): e3000848, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32898131

RESUMO

Improper lengths of actin-thin filaments are associated with altered contractile activity and lethal myopathies. Leiomodin, a member of the tropomodulin family of proteins, is critical in thin filament assembly and maintenance; however, its role is under dispute. Using nuclear magnetic resonance data and molecular dynamics simulations, we generated the first atomic structural model of the binding interface between the tropomyosin-binding site of cardiac leiomodin and the N-terminus of striated muscle tropomyosin. Our structural data indicate that the leiomodin/tropomyosin complex only forms at the pointed end of thin filaments, where the tropomyosin N-terminus is not blocked by an adjacent tropomyosin protomer. This discovery provides evidence supporting the debated mechanism where leiomodin and tropomodulin regulate thin filament lengths by competing for thin filament binding. Data from experiments performed in cardiomyocytes provide additional support for the competition model; specifically, expression of a leiomodin mutant that is unable to interact with tropomyosin fails to displace tropomodulin at thin filament pointed ends and fails to elongate thin filaments. Together with previous structural and biochemical data, we now propose a molecular mechanism of actin polymerization at the pointed end in the presence of bound leiomodin. In the proposed model, the N-terminal actin-binding site of leiomodin can act as a "swinging gate" allowing limited actin polymerization, thus making leiomodin a leaky pointed-end cap. Results presented in this work answer long-standing questions about the role of leiomodin in thin filament length regulation and maintenance.


Assuntos
Citoesqueleto de Actina/metabolismo , Proteínas dos Microfilamentos/química , Proteínas dos Microfilamentos/metabolismo , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Proteínas de Capeamento de Actina/química , Proteínas de Capeamento de Actina/metabolismo , Citoesqueleto de Actina/química , Actinas/química , Actinas/metabolismo , Animais , Animais Recém-Nascidos , Sítios de Ligação , Células Cultivadas , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/metabolismo , Humanos , Camundongos , Modelos Moleculares , Simulação de Dinâmica Molecular , Miocárdio/metabolismo , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Ratos , Sarcômeros/metabolismo
17.
APMIS ; 128(10): 543-551, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32794608

RESUMO

The Hippo pathway is a tumor suppressive pathway regulating Yes-associated protein-TEA domain-containing sequence-specific transcription factor (YAP-TEAD) complex. VGLL (Vestigial-like) proteins are transcriptional cofactors competing with YAP for TEAD binding and interfering oncogenic activity of YAP-TEAD complex. We evaluated the expression of VGLL4, YAP, and TEAD4 and assessed their correlations with clinicopathologic factors and prognostic effects in 295 colorectal cancers. VGLL4 was positive in 164 (55.6%) cases and correlated with small tumor size, low pT classification, and absence of lymph node metastasis. YAP and TEAD4 were highly expressed in 138 (46.8%) cases and 144 (48.8%) cases, respectively, and high expressions were associated with presence of lymphovascular invasion and lymph node metastasis, or distant metastasis. VGLL4 expression was significantly correlated with low YAP expression (p < 0.001) and had significantly better overall survival than negative expression (p < 0.001). High YAP (HR, 2.108; 95% confidence interval, 1.239-3.584; p = 0.006) and TEAD4 (1.724; 1.021-2.912; p = 0.042) expressions were associated with poor overall survivals. The combined VGLL4pos YAPlow expression showed the best overall survival than other groups (p < 0.001). VGLL4 expression (0.381; 0.212-0.683; p = 0.001) and combined VGLL4pos YAPlow expression (0.227; 0.108-0.475; p < 0.001) were independent good prognostic factors in colorectal cancers. The expressions of VGLL4, YAP, and TEAD4 can be used as prognostic markers in colorectal cancer patients.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Biomarcadores Tumorais/análise , Neoplasias Colorretais/patologia , Fatores de Transcrição/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Proteínas de Ligação a DNA/biossíntese , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Musculares/biossíntese , Prognóstico , Análise de Sobrevida
18.
Neurology ; 95(11): e1512-e1527, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32796131

RESUMO

OBJECTIVE: To clarify the prevalence, long-term natural history, and severity determinants of SEPN1-related myopathy (SEPN1-RM), we analyzed a large international case series. METHODS: Retrospective clinical, histologic, and genetic analysis of 132 pediatric and adult patients (2-58 years) followed up for several decades. RESULTS: The clinical phenotype was marked by severe axial muscle weakness, spinal rigidity, and scoliosis (86.1%, from 8.9 ± 4 years), with relatively preserved limb strength and previously unreported ophthalmoparesis in severe cases. All patients developed respiratory failure (from 10.1±6 years), 81.7% requiring ventilation while ambulant. Histopathologically, 79 muscle biopsies showed large variability, partly determined by site of biopsy and age. Multi-minicores were the most common lesion (59.5%), often associated with mild dystrophic features and occasionally with eosinophilic inclusions. Identification of 65 SEPN1 mutations, including 32 novel ones and the first pathogenic copy number variation, unveiled exon 1 as the main mutational hotspot and revealed the first genotype-phenotype correlations, bi-allelic null mutations being significantly associated with disease severity (p = 0.017). SEPN1-RM was more severe and progressive than previously thought, leading to loss of ambulation in 10% of cases, systematic functional decline from the end of the third decade, and reduced lifespan even in mild cases. The main prognosis determinants were scoliosis/respiratory management, SEPN1 mutations, and body mass abnormalities, which correlated with disease severity. We propose a set of severity criteria, provide quantitative data for outcome identification, and establish a need for age stratification. CONCLUSION: Our results inform clinical practice, improving diagnosis and management, and represent a major breakthrough for clinical trial readiness in this not so rare disease.


Assuntos
Genótipo , Proteínas Musculares/genética , Doenças Musculares/diagnóstico por imagem , Doenças Musculares/genética , Selenoproteínas/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Musculares/patologia , Estudos Retrospectivos , Adulto Jovem
19.
Proc Natl Acad Sci U S A ; 117(35): 21288-21298, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817544

RESUMO

The endoplasmic reticulum (ER) is the reservoir for calcium in cells. Luminal calcium levels are determined by calcium-sensing proteins that trigger calcium dynamics in response to calcium fluctuations. Here we report that Selenoprotein N (SEPN1) is a type II transmembrane protein that senses ER calcium fluctuations by binding this ion through a luminal EF-hand domain. In vitro and in vivo experiments show that via this domain, SEPN1 responds to diminished luminal calcium levels, dynamically changing its oligomeric state and enhancing its redox-dependent interaction with cellular partners, including the ER calcium pump sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA). Importantly, single amino acid substitutions in the EF-hand domain of SEPN1 identified as clinical variations are shown to impair its calcium-binding and calcium-dependent structural changes, suggesting a key role of the EF-hand domain in SEPN1 function. In conclusion, SEPN1 is a ER calcium sensor that responds to luminal calcium depletion, changing its oligomeric state and acting as a reductase to refill ER calcium stores.


Assuntos
Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas Sensoras de Cálcio Intracelular/metabolismo , Proteínas Musculares/metabolismo , Selenoproteínas/metabolismo , Células HeLa , Humanos , Proteínas Sensoras de Cálcio Intracelular/genética , Proteínas Musculares/genética , Oxirredução , Selenoproteínas/genética
20.
Proc Natl Acad Sci U S A ; 117(36): 22544-22551, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32826330

RESUMO

Obesity is a major health problem worldwide, given its growing incidence and its association with a variety of comorbidities. Weight gain results from an increase in energy intake without a concomitant increase in energy expenditure. To combat the obesity epidemic, many studies have focused on the pathways underlying satiety and hunger signaling, while other studies have concentrated on the mechanisms involved in energy expenditure, most notably adaptive thermogenesis. Hypothyroidism in humans is typically associated with a decreased basal metabolic rate, lower energy expenditure, and weight gain. However, hypothyroid mouse models have been reported to have a leaner phenotype than euthyroid controls. To elucidate the mechanism underlying this phenomenon, we used a drug-free mouse model of hypothyroidism: mice lacking the sodium/iodide symporter (NIS), the plasma membrane protein that mediates active iodide uptake in the thyroid. In addition to being leaner than euthyroid mice, owing in part to reduced food intake, these hypothyroid mice show signs of compensatory up-regulation of the skeletal-muscle adaptive thermogenic marker sarcolipin, with an associated increase in fatty acid oxidation (FAO). Neither catecholamines nor thyroid-stimulating hormone (TSH) are responsible for sarcolipin expression or FAO stimulation; rather, thyroid hormones are likely to negatively regulate both processes in skeletal muscle. Our findings indicate that hypothyroidism in mice results in a variety of metabolic changes, which collectively lead to a leaner phenotype. A deeper understanding of these changes may make it possible to develop new strategies against obesity.


Assuntos
Hipotireoidismo/metabolismo , Músculo Esquelético/metabolismo , Termogênese/fisiologia , Animais , Modelos Animais de Doenças , Ingestão de Alimentos/fisiologia , Masculino , Camundongos , Camundongos Knockout , Proteínas Musculares/metabolismo , Fenótipo , Proteolipídeos/metabolismo , Simportadores/genética , Simportadores/metabolismo
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