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1.
J Cachexia Sarcopenia Muscle ; 14(6): 2882-2897, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37964752

RESUMO

BACKGROUND: Decreased ryanodine receptor type 1 (RyR1) protein levels are a well-described feature of recessive RYR1-related myopathies. The aim of the present study was twofold: (1) to determine whether RyR1 content is also decreased in other myopathies and (2) to investigate the mechanisms by which decreased RyR1 protein triggers muscular disorders. METHODS: We used publicly available datasets, muscles from human inflammatory and mitochondrial myopathies, an inducible muscle-specific RYR1 recessive mouse model and RyR1 knockdown in C2C12 muscle cells to measure RyR1 content and endoplasmic reticulum (ER) stress markers. Proteomics, lipidomics, molecular biology and transmission electron microscopy approaches were used to decipher the alterations associated with the reduction of RyR1 protein levels. RESULTS: RYR1 transcripts were reduced in muscle samples of patients suffering from necrotizing myopathy (P = 0.026), inclusion body myopathy (P = 0.003), polymyositis (P < 0.001) and juvenile dermatomyositis (P < 0.001) and in muscle samples of myotonic dystrophy type 2 (P < 0.001), presymptomatic (P < 0.001) and symptomatic (P < 0.001) Duchenne muscular dystrophy, Becker muscular dystrophy (P = 0.004) and limb-girdle muscular dystrophy type 2A (P = 0.004). RyR1 protein content was also significantly decreased in inflammatory myopathy (-75%, P < 0.001) and mitochondrial myopathy (-71%, P < 0.001) muscles. Proteomics data showed that depletion of RyR1 protein in C2C12 myoblasts leads to myotubes recapitulating the common molecular alterations observed in myopathies. Mechanistically, RyR1 protein depletion reduces ER-mitochondria contact length (-26%, P < 0.001), Ca2+ transfer to mitochondria (-48%, P = 0.002) and the mitophagy gene Parkinson protein 2 transcripts (P = 0.037) and induces mitochondrial accumulation (+99%, P = 0.005) and dysfunction (P < 0.001). This was associated to the accumulation of deleterious sphingolipid species. Our data showed increased levels of the ER stress marker chaperone-binding protein/glucose regulated protein 78, GRP78-Bip, in RyR1 knockdown myotubes (+45%, P = 0.046), in mouse RyR1 recessive muscles (+58%, P = 0.001) and in human inflammatory (+96%, P = 0.006) and mitochondrial (+64%, P = 0.049) myopathy muscles. This was accompanied by increased protein levels of the pro-apoptotic protein CCAAT-enhancer-binding protein homologous protein, CHOP-DDIT3, in RyR1 knockdown myotubes (+27%, P < 0.001), mouse RyR1 recessive muscles (+63%, P = 0.009), human inflammatory (+50%, P = 0.038) and mitochondrial (+51%, P = 0.035) myopathy muscles. In publicly available datasets, the decrease in RYR1 content in myopathies was also associated to increased ER stress markers and RYR1 transcript levels are inversely correlated with ER stress markers in the control population. CONCLUSIONS: Decreased RyR1 is commonly observed in myopathies and associated to ER stress in vitro, in mouse muscle and in human myopathy muscles, suggesting a potent role of RyR1 depletion-induced ER stress in the pathogenesis of myopathies.


Assuntos
Doenças Musculares , Canal de Liberação de Cálcio do Receptor de Rianodina , Animais , Humanos , Camundongos , Estresse do Retículo Endoplasmático , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/patologia , Doenças Musculares/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo
2.
Ann Clin Transl Neurol ; 6(6): 1072-1080, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31211171

RESUMO

BACKGROUND: A 49-year-old male presented with late-onset demyelinating peripheral neuropathy, cerebellar atrophy, and cognitive deficit. Nerve biopsy revealed intra-axonal inclusions suggestive of polyglucosan bodies, raising the suspicion of adult polyglucosan bodies disease (OMIM 263570). METHODS AND RESULTS: While known genes associated with polyglucosan bodies storage were negative, whole-exome sequencing identified an unreported monoallelic variant, c.397G>T (p.Val133Phe), in the histidyl-tRNA synthetase (HARS) gene. While we did not identify mutations in genes known to be associated with polygucosan body disease, whole-exome sequencing revealed an unreported monoallelic variant, c.397G>T in the histidyl-tRNA synthetase (HARS) gene, encoding a substitution (Val133Phe) in the catalytic domain. Expression of this variant in patient cells resulted in reduced aminoacylation activity in extracts obtained from dermal fibroblasts, without compromising overall protein synthesis. INTERPRETATION: Genetic variants in the genes coding for the different aminoacyl-tRNA synthases are associated with various clinical conditions. To date, a number of HARS variant have been associated with peripheral neuropathy, but not cognitive deficits. Further studies are needed to explore why HARS mutations confer a neuronal-specific phenotype.


Assuntos
Disfunção Cognitiva/genética , Disfunção Cognitiva/patologia , Histidina-tRNA Ligase/genética , Doenças do Sistema Nervoso Periférico/genética , Doenças do Sistema Nervoso Periférico/patologia , Adulto , Alelos , Aminoacilação , Encéfalo/diagnóstico por imagem , Fibroblastos/ultraestrutura , Glucanos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Sequenciamento do Exoma
3.
Neuro Oncol ; 21(7): 923-933, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-30753611

RESUMO

BACKGROUND: Peptide vaccines offer the opportunity to elicit glioma-specific T cells with tumor killing ability. Using antigens eluted from the surface of glioblastoma samples, we designed a phase I/II study to test safety and immunogenicity of the IMA950 multipeptide vaccine adjuvanted with poly-ICLC (polyinosinic-polycytidylic acid stabilized with polylysine and carboxymethylcellulose) in human leukocyte antigen A2+ glioma patients. METHODS: Adult patients with newly diagnosed glioblastoma (n = 16) and grade III astrocytoma (n = 3) were treated with radiochemotherapy followed by IMA950/poly-ICLC vaccination. The first 6 patients received IMA950 (9 major histocompatibility complex [MHC] class I and 2 MHC class II peptides) intradermally and poly-ICLC intramuscularly (i.m.). After protocol amendment, IMA950 and poly-ICLC were mixed and injected subcutaneously (n = 7) or i.m. (n = 6). Primary endpoints were safety and immunogenicity. Secondary endpoints were overall survival, progression-free survival at 6 and 9 months, and vaccine-specific peripheral cluster of differentiation (CD)4 and CD8 T-cell responses. RESULTS: The IMA950/poly-ICLC vaccine was safe and well tolerated. Four patients presented cerebral edema with rapid recovery. For the first 6 patients, vaccine-induced CD8 T-cell responses were restricted to a single peptide and CD4 responses were absent. After optimization of vaccine formulation, we observed multipeptide CD8 and sustained T helper 1 CD4 T-cell responses. For the entire cohort, CD8 T-cell responses to a single or multiple peptides were observed in 63.2% and 36.8% of patients, respectively. Median overall survival was 19 months for glioblastoma patients. CONCLUSION: We provide, in a clinical trial, using cell surface-presented antigens, insights into optimization of vaccines generating effector T cells for glioma patients. TRIAL REGISTRATION: Clinicaltrials.gov NCT01920191.


Assuntos
Astrocitoma/terapia , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/administração & dosagem , Carboximetilcelulose Sódica/análogos & derivados , Quimiorradioterapia/mortalidade , Glioblastoma/terapia , Peptídeos/administração & dosagem , Poli I-C/administração & dosagem , Polilisina/análogos & derivados , Vacinas de Subunidades Antigênicas/administração & dosagem , Adulto , Idoso , Astrocitoma/imunologia , Astrocitoma/patologia , Carboximetilcelulose Sódica/administração & dosagem , Terapia Combinada , Feminino , Seguimentos , Glioblastoma/imunologia , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Polilisina/administração & dosagem , Prognóstico , Taxa de Sobrevida , Adulto Jovem
4.
Int J Legal Med ; 131(5): 1341-1345, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28444440

RESUMO

Paradoxical undressing is a phenomenon characterizing some fatal hypothermia cases. The victims, despite low environmental temperatures, paradoxically remove their clothes due to a sudden feeling of warmth. In this report, we describe a case of suspected paradoxical undressing in a non-hypothermia case. The victim, a 51-year-old Caucasian man, was found dead wearing only sneakers and socks. All other clothing was found in his car. Postmortem investigations allowed the hypothesis of hypothermia to be ruled out and revealed the presence of a ruptured cerebral aneurysm that caused a subarachnoid hemorrhage, the latter responsible for the death. The absence of any elements suggesting a voluntary undressing or any third party's DNA profile or involvement along with the possibility that the subarachnoid hemorrhage might have determined a hypothalamic injury, somehow rendered conceivable the hypothesis of an inappropriate feeling of warmth due to hemorrhage-induced dysregulation of the hypothalamic temperature-regulating centers.


Assuntos
Aneurisma Roto , Vestuário , Aneurisma Intracraniano , Hemorragia Subaracnóidea/patologia , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/patologia , Regulação da Temperatura Corporal/fisiologia , Diagnóstico Diferencial , Patologia Legal , Humanos , Hipotálamo/fisiopatologia , Hipotermia/diagnóstico , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Masculino , Pessoa de Meia-Idade , Hemorragia Subaracnóidea/fisiopatologia
6.
J Neurooncol ; 114(3): 319-27, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23813228

RESUMO

Long term quality of life data of adult patients harboring intracranial ependymomas have not been reported. The role of adjuvant radiation therapy in Grade II ependymomas is unclear and differs from study to study. We therefore sought to retrospectively analyze outcome and quality of life of adult patients that were operated on intracranial ependymomas at four different surgical centers in two countries. All patients were attempted to be contacted via telephone to assess quality of life (QoL) at the time of the telephone interview. The standard EORTC QoL Questionnaire C30 (EORTC QLQ-C30) and the EORTC QLQ-Brain Cancer Module (QLQ-BN20) were used. 64 adult patients with intracranial ependymomas were included in the study. The only factor that was associated with increased survival was age <55 years (p < 0.001). Supratentorial location was correlated with shorter progression free survival than infratentorial location (PFS; p = 0.048). In WHO Grade II tumors local irradiation did not lead to increased PFS (p = 0.888) or overall survival (p = 0.801). Even for incompletely resected Grade II tumors local irradiation did not lead to a benefit in PFS (p = 0.911). In a multivariate analysis of QoL, irradiated patients had significantly worse scores in the item "fatigue" (p = 0.037) than non-irradiated patients. Here we present QoL data of adult patients with intracranial ependymomas. Our data show that local radiation therapy may have long-term effects on patients' QoL. Since in the incompletely resected Grade II tumors local irradiation did not lead to a benefit in PFS in this retrospective study, prospective randomized studies are necessary. In addition to age, supratentorial tumor location is associated with a worse prognosis in adult ependymoma patients.


Assuntos
Neoplasias Encefálicas/mortalidade , Irradiação Craniana , Ependimoma/mortalidade , Procedimentos Neurocirúrgicos , Adulto , Idoso , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Terapia Combinada , Ependimoma/patologia , Ependimoma/terapia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Qualidade de Vida , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
8.
Science ; 318(5855): 1472-5, 2007 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-18048693

RESUMO

JAM-C is an adhesion molecule that is expressed on cells within the vascular compartment and epithelial cells and, to date, has been largely studied in the context of inflammatory events. Using immunolabeling procedures in conjunction with confocal and electron microscopy, we show here that JAM-C is also expressed in peripheral nerves and that this expression is localized to Schwann cells at junctions between adjoining myelin end loops. Sciatic nerves from JAM-C-deficient [having the JAM-C gene knocked out (KO)] mice exhibited loss of integrity of the myelin sheath and defective nerve conduction as indicated by morphological and electrophysiological studies, respectively. In addition, behavioral tests showed motor abnormalities in the KO animals. JAM-C was also expressed in human sural nerves with an expression profile similar to that seen in mice. These results demonstrate that JAM-C is a component of the autotypic junctional attachments of Schwann cells and plays an important role in maintaining the integrity and function of myelinated peripheral nerves.


Assuntos
Moléculas de Adesão Celular/metabolismo , Imunoglobulinas/metabolismo , Proteínas de Membrana/metabolismo , Bainha de Mielina/fisiologia , Fibras Nervosas Mielinizadas/fisiologia , Nervos Periféricos/metabolismo , Células de Schwann/metabolismo , Potenciais de Ação , Animais , Humanos , Junções Intercelulares/metabolismo , Camundongos , Camundongos Knockout , Bainha de Mielina/metabolismo , Bainha de Mielina/ultraestrutura , Fibras Nervosas Mielinizadas/metabolismo , Fibras Nervosas Mielinizadas/ultraestrutura , Condução Nervosa , Nervos Periféricos/fisiologia , Doenças do Sistema Nervoso Periférico/metabolismo , Doenças do Sistema Nervoso Periférico/patologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Nervo Isquiático/metabolismo , Nervo Isquiático/fisiologia , Nervo Isquiático/ultraestrutura , Nervo Sural/metabolismo , Nervo Sural/fisiologia
9.
Medicine (Baltimore) ; 84(3): 188-196, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15879908

RESUMO

Pituitary apoplexy is an ill-defined clinical entity. Some authors include hypoxic pituitary infarction, even in the absence of tumor after hemorrhagic delivery, whereas others apply this term strictly to hemorrhage within a pituitary adenoma. We conducted the present study to establish the prevalence, clinical characteristics, and outcome of pituitary apoplexy, defined as an endocrine crisis characterized by acute intense headache, with or without altered consciousness, rapid development of visual or motor ocular disorders, and pituitary failure, associated with a large pituitary adenoma. We describe 8 consecutive patients (1 woman and 7 men, aged 29-66 yr) presenting over 12 months with pituitary apoplexy. We reviewed patient charts for symptoms, imaging characteristics, hormonal data, management, pathologic findings, and outcome. We examined our pituitary tumors database for cases of macroadenoma without apoplexy occurring during the same period. In 5 patients, potential precipitating factors were present. In 6 patients (3 nonsecreting tumors, 1 free-alpha-subunit-secreting tumor, 1 growth hormone and prolactin-secreting tumor with acromegaly, and 1 prolactinoma), no pituitary disease was suspected before the acute event, representing 19% of newly diagnosed pituitary macroadenomas during the same period of time, a higher proportion than expected from our previously published series. The 2 other patients had known pituitary macroadenomas, a nonsecreting tumor and a prolactinoma on dopamine agonist therapy. Pituitary insufficiency at diagnosis included adrenal failure in 4 patients. Transsphenoidal tumor removal was performed 3-9 days after the onset of symptoms (mean, 5.3 d) in 7 of the 8 patients. Pathologic analysis disclosed tumor hemorrhage in 4 cases, ischemic necrosis in 2, and ischemia after intrasellar hemorrhage in 1. Preoperative magnetic resonance imaging was more sensitive than computed tomography for identifying hemorrhage. The newly diagnosed prolactinoma was treated with dopamine agonist. Complete neuro-ophthalmic recovery was observed in all cases, but only 2 patients displayed normal pituitary function on follow-up. The other 6 patients required long-term hormone replacement therapy. These data show that early surgical decompression prevents persistent neuro-ophthalmic deficit, but does not prevent persistent pituitary insufficiency. Moreover, published data indicate that the efficacy of surgery for the relief of neuro-ophthalmic symptoms decreases with increasing syndrome duration. Our data confirm that apoplexy occurs most often as the inaugural manifestation of pituitary macroadenoma, and suggest a recent increase of cases of apoplexy in our area.


Assuntos
Adenoma/complicações , Apoplexia Hipofisária/etiologia , Neoplasias Hipofisárias/complicações , Adenoma/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos
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