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1.
Hum Mol Genet ; 32(10): 1711-1721, 2023 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-36661122

RESUMEN

Nemaline myopathy (NM) is a rare neuromuscular disorder associated with congenital or childhood-onset of skeletal muscle weakness and hypotonia, which results in limited motor function. NM is a genetic disorder and mutations in 12 genes are known to contribute to autosomal dominant or recessive forms of the disease. Recessive mutations in nebulin (NEB) are the most common cause of NM affecting about 50% of patients. Because of the large size of the NEB gene and lack of mutational hot spots, developing therapies that can benefit a wide group of patients is challenging. Although there are several promising therapies under investigation, there is no cure for NM. Therefore, targeting disease modifiers that can stabilize or improve skeletal muscle function may represent alternative therapeutic strategies. Our studies have identified Nrap upregulation in nebulin deficiency that contributes to structural and functional deficits in NM. We show that genetic ablation of nrap in nebulin deficiency restored sarcomeric disorganization, reduced protein aggregates and improved skeletal muscle function in zebrafish. Our findings suggest that Nrap is a disease modifier that affects skeletal muscle structure and function in NM; thus, therapeutic targeting of Nrap in nebulin-related NM and related diseases may be beneficial for patients.


Asunto(s)
Miopatías Nemalínicas , Animales , Sarcómeros/genética , Sarcómeros/metabolismo , Pez Cebra/genética , Músculo Esquelético/metabolismo , Mutación
2.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34260377

RESUMEN

Duchenne muscular dystrophy (DMD) is a devastating genetic disease leading to degeneration of skeletal muscles and premature death. How dystrophin absence leads to muscle wasting remains unclear. Here, we describe an optimized protocol to differentiate human induced pluripotent stem cells (iPSC) to a late myogenic stage. This allows us to recapitulate classical DMD phenotypes (mislocalization of proteins of the dystrophin-associated glycoprotein complex, increased fusion, myofiber branching, force contraction defects, and calcium hyperactivation) in isogenic DMD-mutant iPSC lines in vitro. Treatment of the myogenic cultures with prednisolone (the standard of care for DMD) can dramatically rescue force contraction, fusion, and branching defects in DMD iPSC lines. This argues that prednisolone acts directly on myofibers, challenging the largely prevalent view that its beneficial effects are caused by antiinflammatory properties. Our work introduces a human in vitro model to study the onset of DMD pathology and test novel therapeutic approaches.


Asunto(s)
Células Madre Pluripotentes Inducidas/patología , Músculo Esquelético/patología , Distrofia Muscular de Duchenne/patología , Prednisolona/farmacología , Fenómenos Biomecánicos , Calcio/metabolismo , Diferenciación Celular/efectos de los fármacos , Línea Celular , Distrofina/deficiencia , Distrofina/metabolismo , Glicoproteínas/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/patología , Músculo Esquelético/efectos de los fármacos , Distrofia Muscular de Duchenne/genética , Mutación/genética , Optogenética , Fenotipo
3.
Mol Biol Rep ; 50(2): 1785-1797, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36462086

RESUMEN

Picobirnaviruses (PBVs) are small non enveloped viruses with bi-segmented ds RNA. They have been observed in a wide variety of vertebrates, including mammals and birds with or without diarrhoea, as well as in sewage samples since its discovery (1988). The source of the viruses is uncertain. True hosts of PBVs and their role as primary pathogens or secondary opportunistic agents or innocuous viruses in the gut remains alien. The mechanisms by which they play a role in pathogenicity are still unclear based on the fact that they can be found in both symptomatic and asymptomatic cases. There is a need to determine their tropism since they have not only been associated with viral gastroenteritis but also been reported in the respiratory tracts of pigs. As zoonotic agents with diverse hosts, the importance of epidemiological and surveillance studies cannot be overstated. The segmented genome of PBV might pose a serious public health issue because of the possibility of continuous genetic reassortment. Aware of the growing attention being given to emerging RNA viruses, we reviewed the current knowledge on PBVs and described the current status of PBVs in animals.


Asunto(s)
Picobirnavirus , Infecciones por Virus ARN , Animales , Porcinos , Picobirnavirus/genética , Filogenia , Infecciones por Virus ARN/veterinaria , Infecciones por Virus ARN/epidemiología , Heces , Diarrea , Mamíferos
4.
Mol Biol Rep ; 50(9): 7347-7356, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37439897

RESUMEN

BACKGROUND: Trypanosoma evansi is a protozoan parasite that can infect a wide range of animals and is widespread around the world. In this study, we analyzed four fatal cases of T. evansi infection using clinical, parasitological, and molecular approaches. We also explored the genetic diversity, demographic history, and population-genetic structure of T. evansi using available Rode Trypanozoon antigenic type (RoTat) 1.2 gene sequences. METHODS AND RESULTS: Clinical findings of infected animals revealed high fever, anemia, weakness, and anorexia. The animals were treated with diminazene aceturate, which was moderately effective, and hematobiochemical parameters showed changes in hemoglobin and glucose levels. The molecular and genetic diversity of T. evansi was analyzed using the RoTat 1.2 VSG gene. Phylogenetic and haplotype analysis revealed two distinct clusters of T. evansi circulating in India. The genetic diversity indices, neutrality tests, gene flow, and genetic differentiation outcomes confirmed the genetic diversity of the T. evansi population, with a lack of uniformity. The identification of two distinct clusters, exhibiting differential demographic histories and evolutionary forces, implies that the clusters may have undergone independent evolutionary trajectories or experienced different environmental pressures. CONCLUSION: The present findings underlined the need of an early and precise diagnosis in order to treat and control T. evansi infections, and the RoTat 1.2 VSG gene is an important genetic marker for understanding the genetic diversity and evolutionary history of T. evansi. This knowledge can be used to create tailored strategies to control and manage the infection in an endemic region.


Asunto(s)
Trypanosoma , Tripanosomiasis , Animales , Caballos , Perros , Tripanosomiasis/veterinaria , Tripanosomiasis/epidemiología , Tripanosomiasis/parasitología , Antígenos de Protozoos/genética , Filogenia , Trypanosoma/genética , Camelus/parasitología , Variación Genética/genética
5.
Brain ; 145(2): 584-595, 2022 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-34894214

RESUMEN

Several studies have confirmed the α-synuclein real-time quaking-induced conversion (RT-QuIC) assay to have high sensitivity and specificity for Parkinson's disease. However, whether the assay can be used as a robust, quantitative measure to monitor disease progression, stratify different synucleinopathies and predict disease conversion in patients with idiopathic REM sleep behaviour disorder remains undetermined. The aim of this study was to assess the diagnostic value of CSF α-synuclein RT-QuIC quantitative parameters in regard to disease progression, stratification and conversion in synucleinopathies. We performed α-synuclein RT-QuIC in the CSF samples from 74 Parkinson's disease, 24 multiple system atrophy and 45 idiopathic REM sleep behaviour disorder patients alongside 55 healthy controls, analysing quantitative assay parameters in relation to clinical data. α-Synuclein RT-QuIC showed 89% sensitivity and 96% specificity for Parkinson's disease. There was no correlation between RT-QuIC quantitative parameters and Parkinson's disease clinical scores (e.g. Unified Parkinson's Disease Rating Scale motor), but RT-QuIC positivity and some quantitative parameters (e.g. Vmax) differed across the different phenotype clusters. RT-QuIC parameters also added value alongside standard clinical data in diagnosing Parkinson's disease. The sensitivity in multiple system atrophy was 75%, and CSF samples showed longer T50 and lower Vmax compared to Parkinson's disease. All RT-QuIC parameters correlated with worse clinical progression of multiple system atrophy (e.g. change in Unified Multiple System Atrophy Rating Scale). The overall sensitivity in idiopathic REM sleep behaviour disorder was 64%. In three of the four longitudinally followed idiopathic REM sleep behaviour disorder cohorts, we found around 90% sensitivity, but in one sample (DeNoPa) diagnosing idiopathic REM sleep behaviour disorder earlier from the community cases, this was much lower at 39%. During follow-up, 14 of 45 (31%) idiopathic REM sleep behaviour disorder patients converted to synucleinopathy with 9/14 (64%) of convertors showing baseline RT-QuIC positivity. In summary, our results showed that α-synuclein RT-QuIC adds value in diagnosing Parkinson's disease and may provide a way to distinguish variations within Parkinson's disease phenotype. However, the quantitative parameters did not correlate with disease severity in Parkinson's disease. The assay distinguished multiple system atrophy patients from Parkinson's disease patients and in contrast to Parkinson's disease, the quantitative parameters correlated with disease progression of multiple system atrophy. Our results also provided further evidence for α-synuclein RT-QuIC having potential as an early biomarker detecting synucleinopathy in idiopathic REM sleep behaviour disorder patients prior to conversion. Further analysis of longitudinally followed idiopathic REM sleep behaviour disorder patients is needed to better understand the relationship between α-synuclein RT-QuIC signature and the progression from prodromal to different synucleinopathies.


Asunto(s)
Atrofia de Múltiples Sistemas , Enfermedad de Parkinson , Trastorno de la Conducta del Sueño REM , Sinucleinopatías , Progresión de la Enfermedad , Humanos , Atrofia de Múltiples Sistemas/diagnóstico , Enfermedad de Parkinson/diagnóstico , Trastorno de la Conducta del Sueño REM/diagnóstico , Sinucleinopatías/diagnóstico , alfa-Sinucleína/análisis
6.
Oral Dis ; 29(8): 3078-3090, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36062371

RESUMEN

This systematic review aims to determine the association between the consumption of sugar-sweetened beverages (SSBs) and periodontal disease. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed to conduct a literature search on five electronic databases till January 2022. Systemically healthy individuals consuming SSBs and presenting periodontal disease (gingivitis/periodontitis) were included. The modified Newcastle-Ottawa Scale and the Grading of Recommendation Assessment Development and Evaluation criteria were respectively used to assess the risk of bias and the evidence's quality. Of the 1303 eligible records identified in the initial search, ten studies (nine cross-sectional and one case-control) were selected for the final review. Among the included articles, five reported SSBs intake in the form of carbonated soft drinks, two as sugary drinks, two as soft drinks, and one as coffee with added sugar. Four studies reported gingivitis as an outcome, while the remaining six studies reported periodontitis using validated indices. The included studies were of medium to high quality. Consumption of SSBs may increase gingival bleeding, thereby gingivitis and the risk of periodontitis. Intake of added sugars like SSBs should be considered as a potential factor during gingival/periodontal risk assessment. Further studies are warranted to establish additional evidence of association.


Asunto(s)
Gingivitis , Enfermedades Periodontales , Periodontitis , Bebidas Azucaradas , Humanos , Bebidas/efectos adversos , Sacarosa en la Dieta/efectos adversos , Estudios Transversales , Enfermedades Periodontales/etiología
7.
Oral Dis ; 29(8): 2993-3002, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35735236

RESUMEN

OBJECTIVE: This systematic review and meta-analysis aimed to estimate the global prevalence of gingival recession (GR) in the general population. MATERIALS AND METHODS: Population-based observational studies reporting the prevalence of GR and published from 1991 to 2021 were identified from five electronic databases and manual searches. Risk of bias was assessed using the Joanna Briggs Institute's Critical Appraisal Checklist for Prevalence Studies. The pooled prevalence of GR was calculated by using a random-effect model. Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach was used to summarize the overall certainty of evidence. RESULTS: A total of 15 studies involving 37,460 participants were included. The overall pooled prevalence was 78.16% at the minimal reported threshold values and 84.92% at ≥1 mm "cut-off" with high heterogeneity among studies. A separate analysis for the buccal GR revealed a pooled prevalence of 75.42%. The risk of bias was found to be high for 10 and low for 5 studies. The overall certainty of the evidence was assessed to be very low. CONCLUSION: More than two-thirds of the population worldwide was found to be affected by GR. Studies with standard case definition and less heterogeneity are required to accurately estimate the prevalence of GR.


Asunto(s)
Recesión Gingival , Humanos , Recesión Gingival/epidemiología , Prevalencia , Estudios Transversales
8.
Phys Chem Earth (2002) ; 129: 103350, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36536697

RESUMEN

Background: With few available effective interventions, emergence of novel mutants responding poorly to existing vaccines and ever swelling newer waves of infection, SARS-CoV-2 is posing difficult challenges to mankind. This mandates development of newer and effective therapeutics to prevent loss of life and contain the spread of this deadly virus. Nsp12 or RNA-dependent RNA polymerase (RdRp) is a suitable druggable target as it plays a central role in viral replication. Methodology: Catalytically important conserved amino acid residues of RdRp were delineated through a comprehensive literature search and multiple sequence alignments. PDB ID 7BV2 was used to create binding pockets using SeeSAR and to generate docked poses of the FDA approved drugs on the receptor and estimating their binding affinity and other properties. Result: In silico approach used in this study assisted in prediction of several potential RdRp inhibitors; and re-validation of the already reported ones. Five molecules namely Inosine, Ribavirin, 2-Deoxy-2-Fluoro-D-glucose, Guaifenesin, and Lamivudine were shortlisted which exhibited reasonable binding affinities, with neither torsional nor intermolecular or intramolecular clashes. Conclusion: This study aimed to widen the prospect of interventions against the SARS-CoV-2 RdRp. Our results also re-validate already reported molecules like 2-Deoxy-D-glucose as a similar molecule 2-deoxy-2-fluoro-D-glucose is picked up in this study. Additionally, ribavirin and lamivudine, already known antivirals with polymerase inhibition activity are also picked up as the top leads. Selected potent inhibitors of RdRp hold promise to cater for any future coronavirus-outbreak subject to in vitro and in vivo validations.

9.
Dev Med Child Neurol ; 64(8): 979-988, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35385138

RESUMEN

AIM: To correlate the North Star Ambulatory Assessment (NSAA) and timed rise from floor (TRF) recorded at age of expected peak with age at loss of ambulation (LOA) in Duchenne muscular dystrophy (DMD). METHOD: Male children with DMD enrolled in the UK North Start Network database were included according to the following criteria: follow-up longer than 3 years, one NSAA record between 6 years and 7 years 6 months (baseline), at least one visit when older than 8 years. Data about corticosteroid treatment, LOA, genotype, NSAA, and TRF were analysed. Age at LOA among the different groups based on NSAA and TRF was determined by log-rank tests. Cox proportional hazard models were used for multivariable analysis. RESULTS: A total of 293 patients from 13 different centres were included. Mean (SD) age at first and last visit was 5 years 6 months (1 year 2 months) and 12 years 8 months (2 years 11 months) (median follow-up 7 years 4 months). Higher NSAA and lower TRF at baseline were associated with older age at LOA (p<0.001). Patients scoring NSAA 32 to 34 had a probability of 0.61 of being ambulant when older than 13 years compared with 0.34 for those scoring 26 to 31. In multivariable analysis, NSAA, TRF, and corticosteroid daily regimen (vs intermittent) were all independently associated with outcome (p=0.01). INTERPRETATION: Higher functional abilities at peak are associated with older age at LOA in DMD. This information is important for counselling families. These baseline measures should also be considered when designing clinical trials.


Asunto(s)
Distrofia Muscular de Duchenne , Actividades Cotidianas , Corticoesteroides/uso terapéutico , Niño , Genotipo , Humanos , Masculino , Distrofia Muscular de Duchenne/complicaciones , Distrofia Muscular de Duchenne/tratamiento farmacológico , Caminata
10.
J Esthet Restor Dent ; 34(3): 445-450, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34927335

RESUMEN

OBJECTIVES: Mucosal fenestrations are infrequent and often challenging to treat depending on the extent of soft and hard tissue destruction. This article presents the successful management of a relatively larger mucosal fenestration associated with complete absence of buccal bone plate in a mandibular incisor secondary to trauma-induced periapical pathosis. CLINICAL CONSIDERATIONS: After non-surgical endodontic therapy, surgery was performed for debridement of the osseous defect, root resection/shaping, connective tissue graft (CTG) placement on the affected root surface and platelet rich fibrin (PRF) in periapical osseous defect rather than use of bone graft and/or barrier membrane. Healing was uneventful, however, a small mucosal defect remained at 2 weeks follow-up. After 3 months of primary surgery, a corrective surgery was performed utilizing an "incision-free" approach i.e. tunnel technique with CTG in contrast to the contemporary flap approach. At 18 months follow-up, complete closure of the mucosal defect with a thick gingival biotype, normal sulcus depth, and good esthetic outcome were achieved. No recurrence and any clinical signs of infection or inflammation were observed. CONCLUSIONS: Based on the outcomes of present case, an early intervention utilizing the minimally invasive surgical therapy and autologous biomaterials may be considered a viable approach to treat such complex lesions. CLINICAL SIGNIFICANCE: Endodontic therapy in combination with PRF and CTG appears to provide successful outcomes in treatment of a large mucosal fenestration with periapical osseous defect.


Asunto(s)
Fibrina Rica en Plaquetas , Tejido Conectivo/trasplante , Estudios de Seguimiento , Encía , Incisivo/patología
11.
Phys Chem Earth (2002) ; 127: 103188, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35757560

RESUMEN

Since its inception, SARS-CoV-2 has crossed all borders and continues rampaging around the globe, causing profound economic damage and heavy burden on the scientific community and the healthcare fraternity and facilities. With the emergence of new variants, the global pandemic has prolonged and raised concerns regarding the existing therapies. Most of the identified mutants have the potential to exacerbate the already existing crisis. In line with the urgent need for promising antivirals against the novel coronavirus, we conducted an in-silico drug docking study using SeeSAR and other bioinformatics tools and identified prospective molecules that target the nucleocapsid protein of SARS-CoV-2. The highly conserved N protein plays a crucial role in viral assembly and pathogenicity by interacting with the host ribosomal subunits and suppressing nonsense mediated decay (NMD) of viral mRNA by the host cell. In the current study, FDA approved drugs were docked into pockets created within the N protein including the crucial conserved residues and analyzed for their affinity. The docked compounds give us novel plausible models that can be inspected further and paves way for the development of potent therapeutics against SARS-CoV-2.

12.
Hum Mol Genet ; 28(15): 2549-2560, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30986853

RESUMEN

Nemaline myopathy (NM) is the most common form of congenital myopathy that results in hypotonia and muscle weakness. This disease is clinically and genetically heterogeneous, but three recently discovered genes in NM encode for members of the Kelch family of proteins. Kelch proteins act as substrate-specific adaptors for Cullin 3 (CUL3) E3 ubiquitin ligase to regulate protein turnover through the ubiquitin-proteasome machinery. Defects in thin filament formation and/or stability are key molecular processes that underlie the disease pathology in NM; however, the role of Kelch proteins in these processes in normal and diseases conditions remains elusive. Here, we describe a role of NM causing Kelch protein, KLHL41, in premyofibil-myofibil transition during skeletal muscle development through a regulation of the thin filament chaperone, nebulin-related anchoring protein (NRAP). KLHL41 binds to the thin filament chaperone NRAP and promotes ubiquitination and subsequent degradation of NRAP, a process that is critical for the formation of mature myofibrils. KLHL41 deficiency results in abnormal accumulation of NRAP in muscle cells. NRAP overexpression in transgenic zebrafish resulted in a severe myopathic phenotype and absence of mature myofibrils demonstrating a role in disease pathology. Reducing Nrap levels in KLHL41 deficient zebrafish rescues the structural and function defects associated with disease pathology. We conclude that defects in KLHL41-mediated ubiquitination of sarcomeric proteins contribute to structural and functional deficits in skeletal muscle. These findings further our understanding of how the sarcomere assembly is regulated by disease-causing factors in vivo, which will be imperative for developing mechanism-based specific therapeutic interventions.


Asunto(s)
Proteínas del Citoesqueleto/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Miopatías Nemalínicas/metabolismo , Ubiquitinación , Animales , Animales Modificados Genéticamente , Modelos Animales de Enfermedad , Técnicas de Inactivación de Genes , Ratones , Miofibrillas/metabolismo , Miopatías Nemalínicas/genética , Miopatías Nemalínicas/fisiopatología , Fenotipo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Pez Cebra/genética , Pez Cebra/metabolismo
13.
Hum Mol Genet ; 28(2): 320-331, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30307508

RESUMEN

Facioscapulohumeral dystrophy type 1 (FSHD-1) is the most common autosomal dominant form of muscular dystrophy with a prevalence of ∼1 in 8000 individuals. It is considered a late-onset form of muscular dystrophy and leads to asymmetric muscle weakness in the facial, scapular, trunk and lower extremities. The prevalent hypothesis on disease pathogenesis is explained by misexpression of a germ line, primate-specific transcription factor DUX4-fl (double homeobox 4, full-length isoform) linked to the chromosome 4q35. In vitro and in vivo studies have demonstrated that very low levels of DUX4-fl expression are sufficient to induce an apoptotic and/or lethal phenotype, and therefore modeling of the disease has proved challenging. In this study, we expand upon our previously established injection model of DUX4 misexpression in zebrafish and describe a DUX4-inducible transgenic zebrafish model that better recapitulates the expression pattern and late onset phenotype characteristic of FSHD patients. We show that an induced burst of DUX4 expression during early development results in the onset of FSHD-like phenotypes in adulthood, even when DUX4 is no longer detectable. We also utilize our injection model to study long-term consequences of DUX4 expression in those that fail to show a developmental phenotype. Herein, we introduce a hypothesis that DUX4 expression during developmental stages is sufficient to induce FSHD-like phenotypes in later adulthood. Our findings point to a developmental role of DUX4 misexpression in the pathogenesis of FSHD and should be factored into the design of future therapies.


Asunto(s)
Músculo Esquelético/metabolismo , Distrofia Muscular Facioescapulohumeral/metabolismo , Proteínas de Pez Cebra/metabolismo , Animales , Animales Modificados Genéticamente , Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Contracción Muscular , Músculo Esquelético/embriología , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Distrofia Muscular Animal , Distrofia Muscular Facioescapulohumeral/embriología , Distrofia Muscular Facioescapulohumeral/etiología , Distrofia Muscular Facioescapulohumeral/genética , Pez Cebra , Proteínas de Pez Cebra/genética
14.
Clin Genet ; 100(6): 748-751, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34424553

RESUMEN

GOGLA2/GM130 is a Golgin protein involved in vesicle tethering, cell proliferation and autophagy. Recessive loss of function mutation in GOLGA2 has been previously reported in a single family with muscular dystrophy and microcephaly. Here we describe a second consanguineous family with the bi-allelic loss of function mutations in GOLGA2. The patient exhibits microcephaly, seizures, and myopathy similar to the previously reported patient with GOLGA2 mutation. This report supports the critical developmental requirement of GOLGA2 and emphasizes a similar and severe clinical presentation with loss of function mutations in affected patients.


Asunto(s)
Autoantígenos/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Mutación con Pérdida de Función , Proteínas de la Membrana/genética , Enfermedades del Sistema Nervioso/diagnóstico , Enfermedades del Sistema Nervioso/genética , Fenotipo , Alelos , Sustitución de Aminoácidos , Consanguinidad , Femenino , Genes Recesivos , Genotipo , Humanos , Lactante , Linaje , Secuenciación del Exoma
15.
Ann Neurol ; 87(4): 568-583, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31970803

RESUMEN

OBJECTIVE: Recessive null variants of the slow skeletal muscle troponin T1 (TNNT1) gene are a rare cause of nemaline myopathy that is fatal in infancy due to respiratory insufficiency. Muscle biopsy shows rods and fiber type disproportion. We report on 4 French Canadians with a novel form of recessive congenital TNNT1 core-rod myopathy. METHODS: Patients underwent full clinical characterization, lower limb magnetic resonance imaging (MRI), muscle biopsy, and genetic testing. A zebrafish loss-of-function model using morpholinos was created to assess the pathogenicity of the identified variant. Wild-type or mutated human TNNT1 mRNAs were coinjected with morpholinos to assess their abilities to rescue the morphant phenotype. RESULTS: Three adults and 1 child shared a novel missense homozygous variant in the TNNT1 gene (NM_003283.6: c.287T > C; p.Leu96Pro). They developed from childhood very slowly progressive limb-girdle weakness with rigid spine and disabling contractures. They suffered from restrictive lung disease requiring noninvasive mechanical ventilation in 3 patients, as well as recurrent episodes of rhabdomyolysis triggered by infections, which were relieved by dantrolene in 1 patient. Older patients remained ambulatory into their 60s. MRI of the leg muscles showed fibrofatty infiltration predominating in the posterior thigh and the deep posterior leg compartments. Muscle biopsies showed multiminicores and lobulated fibers, rods in half the patients, and no fiber type disproportion. Wild-type TNNT1 mRNA rescued the zebrafish morphants, but mutant transcripts failed to do so. INTERPRETATION: This study expands the phenotypic spectrum of TNNT1 myopathy and provides functional evidence for the pathogenicity of the newly identified missense mutation. ANN NEUROL 2020;87:568-583.


Asunto(s)
Músculo Esquelético/patología , Miopatías Nemalínicas/fisiopatología , ARN Mensajero/metabolismo , Troponina T/genética , Animales , Niño , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Morfolinos , Músculo Esquelético/ultraestructura , Miopatías Nemalínicas/genética , Miopatías Nemalínicas/patología , Rabdomiólisis/genética , Rabdomiólisis/fisiopatología , Troponina T/metabolismo , Pez Cebra
16.
Muscle Nerve ; 63(6): 928-940, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33651408

RESUMEN

INTRODUCTION: RNA-binding proteins (RBPs) play an important role in skeletal muscle development and disease by regulating RNA splicing. In myotonic dystrophy type 1 (DM1), the RBP MBNL1 (muscleblind-like) is sequestered by toxic CUG repeats, leading to missplicing of MBNL1 targets. Mounting evidence from the literature has implicated other factors in the pathogenesis of DM1. Herein we sought to evaluate the functional role of the splicing factor hnRNP L in normal and DM1 muscle cells. METHODS: Co-immunoprecipitation assays using hnRNPL and MBNL1 expression constructs and splicing profiling in normal and DM1 muscle cell lines were performed. Zebrafish morpholinos targeting hnrpl and hnrnpl2 were injected into one-cell zebrafish for developmental and muscle analysis. In human myoblasts downregulation of hnRNP L was achieved with shRNAi. Ascochlorin administration to DM1 myoblasts was performed and expression of the CUG repeats, DM1 splicing biomarkers, and hnRNP L expression levels were evaluated. RESULTS: Using DM1 patient myoblast cell lines we observed the formation of abnormal hnRNP L nuclear foci within and outside the expanded CUG repeats, suggesting a role for this factor in DM1 pathology. We showed that the antiviral and antitumorigenic isoprenoid compound ascochlorin increased MBNL1 and hnRNP L expression levels. Drug treatment of DM1 muscle cells with ascochlorin partially rescued missplicing of established early biomarkers of DM1 and improved the defective myotube formation displayed by DM1 muscle cells. DISCUSSION: Together, these studies revealed that hnRNP L can modulate DM1 pathologies and is a potential therapeutic target.


Asunto(s)
Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , Desarrollo de Músculos/genética , Mioblastos/metabolismo , Distrofia Miotónica/genética , Adulto , Animales , Línea Celular , Ribonucleoproteínas Nucleares Heterogéneas/genética , Humanos , Masculino , Persona de Mediana Edad , Mioblastos/patología , Distrofia Miotónica/metabolismo , Distrofia Miotónica/patología , Pez Cebra
17.
Curr Microbiol ; 78(7): 2753-2761, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34037823

RESUMEN

Swine influenza virus (SIV) belongs to family Orthomyxoviridae and can cause acute respiratory infection in pigs. Several pandemic H1N1 human fatal influenza cases were reported in India. Though pigs are predisposed to both avian and human influenza virus infections with the potential to generate novel reassortants, there are only a few reports of SIV in Indian pigs. We conducted a serological survey to assess the status of H1N1 infection in pigs of various states in India, between 2009 and 2016. Based on Haemagglutination inhibition (HI) assay, seroprevalence rate of H1N1 virus ranged between 5.2% (2009) and 36.3% (2011). Widespread prevalence of antibody was observed in eastern Uttar Pradesh from 6.2 to 37.5% during the study period. Co-circulation of seasonal H1N1 virus along with pandemic H1N1 virus was indicated by the presence of specific antibodies against seasonal H1N1 virus in eastern part of Uttar Pradesh. Seroprevalence rate in pigs and influenza infection trend in human shows the possible spill over transmission of influenza to pigs from human. Hence, besides serological surveillance, continuous and systematic molecular surveillance should be implemented in pig population to reduce/quantify the risk and emergence of pandemic influenza.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Gripe Humana , Infecciones por Orthomyxoviridae , Enfermedades de los Porcinos , Animales , Anticuerpos Antivirales , Humanos , India/epidemiología , Gripe Humana/epidemiología , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/veterinaria , Prevalencia , Estudios Seroepidemiológicos , Porcinos , Enfermedades de los Porcinos/epidemiología
18.
PLoS Genet ; 14(3): e1007226, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29518074

RESUMEN

Gene expression in a tissue-specific context depends on the combined efforts of epigenetic, transcriptional and post-transcriptional processes that lead to the production of specific proteins that are important determinants of cellular identity. Ribosomes are a central component of the protein biosynthesis machinery in cells; however, their regulatory roles in the translational control of gene expression in skeletal muscle remain to be defined. In a genetic screen to identify critical regulators of myogenesis, we identified a DEAD-Box RNA helicase, DDX27, that is required for skeletal muscle growth and regeneration. We demonstrate that DDX27 regulates ribosomal RNA (rRNA) maturation, and thereby the ribosome biogenesis and the translation of specific transcripts during myogenesis. These findings provide insight into the translational regulation of gene expression in myogenesis and suggest novel functions for ribosomes in regulating gene expression in skeletal muscles.


Asunto(s)
ARN Helicasas DEAD-box/metabolismo , Músculo Esquelético/fisiología , Biosíntesis de Proteínas , ARN Ribosómico/metabolismo , Animales , Animales Modificados Genéticamente , Línea Celular , Nucléolo Celular/metabolismo , Nucléolo Celular/ultraestructura , Proliferación Celular/genética , ARN Helicasas DEAD-box/genética , Embrión no Mamífero , Ratones , Desarrollo de Músculos/fisiología , Músculo Esquelético/citología , Músculo Esquelético/crecimiento & desarrollo , Mioblastos/citología , Mioblastos/fisiología , Factor de Transcripción PAX2/genética , Factor de Transcripción PAX2/metabolismo , ARN Ribosómico/genética , Regeneración/fisiología , Pez Cebra/embriología , Pez Cebra/genética , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo
19.
Acta Neuropathol ; 137(3): 501-519, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30701273

RESUMEN

The identification of genes implicated in myopathies is essential for diagnosis and for revealing novel therapeutic targets. Here we characterize a novel subclass of congenital myopathy at the morphological, molecular, and functional level. Through exome sequencing, we identified de novo ACTN2 mutations, a missense and a deletion, in two unrelated patients presenting with progressive early-onset muscle weakness and respiratory involvement. Morphological and ultrastructural analyses of muscle biopsies revealed a distinctive pattern with the presence of muscle fibers containing small structured cores and jagged Z-lines. Deeper analysis of the missense mutation revealed mutant alpha-actinin-2 properly localized to the Z-line in differentiating myotubes and its level was not altered in muscle biopsy. Modelling of the disease in zebrafish and mice by exogenous expression of mutated alpha-actinin-2 recapitulated the abnormal muscle function and structure seen in the patients. Motor deficits were noted in zebrafish, and muscle force was impaired in isolated muscles from AAV-transduced mice. In both models, sarcomeric disorganization was evident, while expression of wild-type alpha-actinin-2 did not result in muscle anomalies. The murine muscles injected with mutant ACTN2 displayed cores and Z-line defects. Dominant ACTN2 mutations were previously associated with cardiomyopathies, and our data demonstrate that specific mutations in the well-known Z-line regulator alpha-actinin-2 can cause a skeletal muscle disorder.


Asunto(s)
Actinina/genética , Músculo Esquelético/patología , Miotonía Congénita/genética , Miotonía Congénita/patología , Animales , Femenino , Humanos , Masculino , Ratones , Mutación , Pez Cebra
20.
J Nanosci Nanotechnol ; 19(2): 646-654, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30360136

RESUMEN

Metal organic frameworks (MOFs), MIL-101-Fe (Materials of Institute Lavoisier), have been synthesized by solvothermal method. The as-synthesized MIL-101-Fe particles are observed to have hexagonal shaped morphology with average particle size ranging from 480 to 500 nm. The functionalization of the surface of as-synthesized MIL-101-Fe particles was done with the integration of amine group into the framework to facilitate the conjugation of the drug and other entities. Further, the drug conjugated MOF particles were coated with polyethyleneglycol (PEG) layer so as to extend the drug release time by controlling the faster pH mediated MOF degradation in biological buffers. pH dependent drug release study of the MOF particles was carried out at 3 different pH values, i.e., 5, 6 and 7.4. The drug release profiles showed that the drug released from NH2-MIL-101-Fe takes less time which was further increased after coating the NH2-MIL-101-Fe with polyethyleneglycol (PEG@Drug@NH2-MIL-101-Fe). This confirmed that PEG coated particles have great stability for drug delivery application.


Asunto(s)
Estructuras Metalorgánicas , Preparaciones Farmacéuticas , Sistemas de Liberación de Medicamentos , Concentración de Iones de Hidrógeno , Hierro
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