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1.
Neurol Sci ; 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38261153

RESUMO

BACKGROUND: Variant transthyretin amyloidosis (ATTRv) can cause sensorimotor and autonomic neuropathy. Objective quantification of sudomotor function may be essential for early diagnosis and early initiation of treatment. The aim of this study is to evaluate the diagnostic value of the Sudoscan® in ATTRv. METHODS: Electrochemical skin conductance (ESC) was measured in V30M ATTRv patients, asymtomatic V30M carriers and healthy controls. Comparisons between the three groups were made using the Kruskal-Wallis test, and ROC curves were used to estimate the discriminatory power of ESC values between groups. RESULTS: ESC was measured in 52 ATTRv patients, 107 asymptomatic carriers and 40 healthy controls. ESC was significantly lower in ATTRv patients compared to asymptomatic carriers and healthy controls in both feet and hands; median values are as follows: 40 µS, 78 µS and 81 µS, respectively (p < 0.001), and 53 µS, 69 µS and 74 µS, respectively (p < 0.001). ESC in feet < 70.5 µS had a sensitivity of 89.7% and specificity of 84.6% to discriminate asymptomatic carriers from patients with ATTRv. CONCLUSION: The determination of ESC by Sudoscan® is a rapid, noninvasive and easily reproducible technique capable of discriminating patients with ATTRv from asymptomatic carriers and healthy controls with adequate sensitivity and specificity.

2.
Sci Rep ; 14(1): 581, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182630

RESUMO

Early identification of ATTRv amyloidosis disease onset is still often delayed due to the lack of validated biomarkers of this disease. Light chain neurofilament (NfL) have shown promising results in early diagnosis in this disease, but data is still needed, including with alternative measuring methods. Our aim was to study the levels of NfL measured by ELISA. Furthermore, interstitial matrix metalloproteinase type 1 (MMP-1) serum levels were measured as a potential new biomarker in ATTRv. Serum NfL and MMP-1 were measured using ELISA assays in 90 participants (29 ATTR-V30M patients, 31 asymptomatic V30M-TTR variant carriers and 30 healthy controls). Median NfL levels among ATTRv amyloidosis patients were significantly higher (116 pg/mL vs 0 pg/mL in both comparison groups). The AUC comparing ATTRv amyloidosis patients and asymptomatic carriers was 0.90 and the NfL concentration of 93.55 pg/mL yielded a sensitivity of 79% and a specificity of 87%. NfL levels had a significant positive correlation with NIS values among patients. We found a negative significant correlation between eGFR and NfL levels. Finally, MMP1 levels were not different between groups. Evidence of NfL use for early diagnosis of ATTR-PN amyloidosis is growing. ELISA seems a reliable and available technique for it quantification. Decreased GFR could influence NfL plasma levels.


Assuntos
Neuropatias Amiloides Familiares , Metaloproteinase 1 da Matriz , Humanos , Neuropatias Amiloides Familiares/diagnóstico , Diagnóstico Precoce , Biomarcadores
3.
Orphanet J Rare Dis ; 18(1): 352, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37950297

RESUMO

BACKGROUND: Hereditary transthyretin amyloidosis (ATTRv) is a rare genetic disease that negatively affects patients' quality of life through the involvement of various organs and tissues. Despite a large amount of research on medical and psychosocial interventions, the impact of occupational therapy (OT) on patients with ATTRv is not well understood. OBJECTIVE: The aim of this study was to develop an OT programme to improve the daily functioning and quality of life of patients with ATTRv. METHODS: Fourteen patients with ATTRv were interviewed. Together they developed short- and medium-term occupational goals. Patients received the OT intervention for six months. Outcomes were measured using scores for activities of daily living and psychological well-being. RESULTS: The study found that OT can have a positive impact as a complementary intervention to medical and other psychosocial treatments. Of the 14 patients, 12 maintained the same scores in activities of daily living. Two deteriorated and eight improved their psychological scores. CONCLUSION: This study highlights the need for further research in this area and the importance of OT in the management of patients with ATTRv. Early intervention is of paramount importance and further research is needed to evaluate the long-term effects of OT interventions in patients with ATTRv.


Assuntos
Atividades Cotidianas , Neuropatias Amiloides Familiares , Humanos , Qualidade de Vida , Neuropatias Amiloides Familiares/terapia , Pesquisa Qualitativa , Doenças Raras
4.
Amyloid ; 30(3): 313-320, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36994840

RESUMO

BACKGROUND: In hereditary transthyretin amyloidosis (ATTRv), early manifestation and age at onset (AO) may vary strikingly. We assessed the disease'risk (penetrance), AO and initial features in ATTRv families to gain insights on the early disease presentation. METHODS: Genealogical information, AO and first disease manifestations were collected in ATTRv families, from Sweden, Italy (Sicily), Spain (Mallorca), France, Turkey, Brazil. Penetrance was computed using a non-parametric survival method. RESULTS: We analysed 258 TTRV30M kindreds and 84 carrying six other variants (TTRT49A, F64L, S77Y, S77F, E89Q, I107V). In ATTRV30M families, the earliest disease risk was found at age 20 years in the Portuguese and Mallorcan families and at age 30-35 years, in the French and Swedish groups. The risks were higher in men and in carriers of maternal descent. In families carrying TTR-nonV30M variants, the earliest disease risk ranged from 30 y-o in TTRT49A to 55 y-o in TTRI107V families. Peripheral neuropathy symptoms were the most frequent initial manifestations. Among patients carrying TTRnonV30M variants, about 25% had an initial cardiac phenotype, one third a mixed phenotype. CONCLUSION: Our work provided solid data on the risks and early features of ATTRv in a spectrum of families to enhance an early diagnosis and treatment.


Assuntos
Neuropatias Amiloides Familiares , Humanos , Masculino , Neuropatias Amiloides Familiares/diagnóstico , Neuropatias Amiloides Familiares/genética , Brasil , Diagnóstico Precoce , Etnicidade , Pré-Albumina/genética
5.
Front Oncol ; 12: 995357, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36531066

RESUMO

Pancreatic cancer adenocarcinoma (PDAC) is a lethal disease, with the lowest 5-years survival rate of all cancers due to late diagnosis. Despite the advance and success of precision oncology in gastrointestinal cancers, the frequency of molecular-informed therapy decisions in PDAC is currently neglectable. The reasons for this dismal situation are mainly the absence of effective early diagnostic biomarkers and therapy resistance. PDAC cancer stem cells (PDAC-SC), which are regarded as essential for tumor initiation, relapse and drug resistance, are highly dependent on their niche i.e. microanatomical structures of the tumor microenvironment. There is an altered microbiome in PDAC patients embedded within the highly desmoplastic tumor microenvironment, which is known to determine therapeutic responses and affecting survival in PDAC patients. We consider that understanding the communication network that exists between the microbiome and the PDAC-SC niche by co-culture of patient-derived organoids (PDOs) with TME microbiota would recapitulate the complexity of PDAC paving the way towards a precision oncology treatment-response prediction.

6.
Artigo em Inglês | MEDLINE | ID: mdl-36141995

RESUMO

The purpose of this study was to explore the occupational performance and needs of patients with hereditary transthyretin amyloidosis (ATTRv). A semi-structured interview was conducted by an occupational therapist with 44 patients with Val50Met-ATTRv recruited through patient associations. The interview addressed three related dimensions. The first one, the physical dimension, was evaluated using the Spanish versions of the Barthel Index, the Lawton and Brody scale, and the Norfolk questionnaire; the second one, the psychological dimension, was assessed with the Warwick-Edinburgh Mental Well-Being Scale and the SF-36 questionnaire; and the third dimension, the occupational performance, was assessed through unstructured questions on daily occupations, work, roles, and hobbies given the lack of standardized scales. Twenty participants (45.4%) responded that the disease had affected their basic activities of daily living, twenty- four (54.5%) perceived an impact on their instrumental activities of daily living, and all the participants reported that the disease symptoms had affected their ability to perform advanced activities as well as their employment status. Only three patients (6.8%) reported a lack of psychological impairment following disease diagnosis. These findings suggest that a semi-structured interview conducted by an occupational therapist can provide essential information that should be considered for the implementation of occupational therapy programs targeting patients living with a diagnosis of ATTRv.


Assuntos
Neuropatias Amiloides Familiares , Terapia Ocupacional , Atividades Cotidianas , Neuropatias Amiloides Familiares/complicações , Humanos
7.
Artigo em Inglês | MEDLINE | ID: mdl-35457333

RESUMO

This study was designed to investigate the global utilization of occupational therapy (OT) services by patients with hereditary transthyretin amyloidosis (ATTRv) in Spain. The main objective was to find out whether these patients have access to OT services and the types of interventions being offered to them, together with their satisfaction and real benefits as users. We developed an online questionnaire which was distributed to patients with ATTRv in Spain through patient associations. Seventy-four patients with a diagnosis of ATTRv residing in Spain participated in the study. Thirteen had already used OT services at least once, felt that OT interventions improved their quality of life, would recommend OT services to others, and would return to see an occupational therapist. However, 61 had never used this type of service before. Of these, 35 knew what OT is and 13 declared that they considered that OT interventions in ATTRv could be positive for them. The results suggest that the use of OT services by ATTRv patients is low, mainly because of the lack of information about the occupational profile of individuals with this disease. The low response rate obtained for the survey limits generalization, and thus further research to confirm these preliminary findings is needed.


Assuntos
Neuropatias Amiloides Familiares , Terapia Ocupacional , Neuropatias Amiloides Familiares/complicações , Neuropatias Amiloides Familiares/diagnóstico , Neuropatias Amiloides Familiares/terapia , Humanos , Qualidade de Vida , Inquéritos e Questionários
8.
Neurol Ther ; 10(2): 833-845, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34331265

RESUMO

INTRODUCTION: Transthyretin amyloidosis (ATTR amyloidosis) is a clinically heterogeneous disease caused by mutations in the transthyretin (TTR) gene or aggregation of wild-type transthyretin (ATTRwt). In Spain, there are two large endemic foci of ATTR amyloidosis caused by the Val30Met variant, with additional cases across the country; however, these data may be incomplete, as there is no centralized patient registry. The Transthyretin Amyloidosis Outcomes Survey (THAOS) is an ongoing, global, longitudinal, observational survey of patients with ATTR amyloidosis, including both inherited and wild-type disease, and asymptomatic patients with TTR mutations. This analysis aimed to gain a deeper understanding of the clinical profile of patients with ATTR amyloidosis in Spain. METHODS: This was a descriptive analysis of the demographic and clinical characteristics of symptomatic patients enrolled at six sites geographically dispersed throughout Spain (data cutoff: January 6, 2020). Patient data at enrollment, including genotype, demographics, and clinical presentation for symptomatic patients, were recorded. Patients were grouped by predominant phenotype based on clinical measures at enrollment: predominantly cardiac, predominantly neurologic, or mixed (cardiac and neurologic). RESULTS: There were 379 patients (58.0% male; 63.3% symptomatic) enrolled in the six THAOS sites in Spain. Predominant genotypes were the Val30Met mutation (69.1%) or ATTRwt (15.6%). Predominant phenotype distribution was neurologic (50.4%), mixed (35.8%), and cardiac (13.8%) for all symptomatic patients (n = 240); neurologic (67.8%), mixed (21.2%), and cardiac (11.0%) for symptomatic Val30Met (n = 146); and mixed (64.9%), cardiac (22.8%), and neurologic (12.3%) for symptomatic ATTRwt (n = 57). Symptomatic patients reported a range of ATTR amyloidosis signs and symptoms at enrollment, with autonomic neuropathy and sensory neuropathy common in all phenotypes. CONCLUSIONS: These results from THAOS highlight the phenotypic heterogeneity associated with ATTR amyloidosis in Spain and the importance of comprehensive neurologic and cardiac evaluations in all patients with ATTR amyloidosis. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00628745.

9.
Orphanet J Rare Dis ; 16(1): 266, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112225

RESUMO

BACKGROUND: Hereditary transthyretin (TTR) amyloidosis (ATTRv) is a heterogeneous disease with a clinical presentation that varies according to geographical area and TTR mutation. The symptoms of Val50Met-ATTRv are mainly neuropathic and progress to complete disability and death in most untreated patients within 10 to 15 years of diagnosis. The neurological effects may also be accompanied by gastrointestinal impairment, cardiomyopathy, nephropathy and/or ocular deposition. The disease is thus associated with a high degree of patient disability. Accordingly, we aimed to describe the psychosocial burden associated with ATTRv in a group of patients, asymptomatic Val50Met carriers, relatives and caregivers in the endemic focus of the disease in Majorca via a survey addressing various aspects related to psychosocial burden. We performed a an observational, descriptive, cross-sectional and multicentre study in order to analyze the prevalence of self-reported impact of ATTRv disease upon their daily life. In addition to the self-knowledge, fear and burden related to the disease. The survey was disseminated during the regular follow up at the outpatient clinic of the Hospital Universitario Son Llàtzer and during the meetings organized by the Andrade's Disease patients' advocacy group from the Balearic Islands. These meetings were attended also by subjects followed up by the Hospital Universitario Son Espases and their caregivers and relatives. Survey was self-administrated. No intervention was done by the investigators. 85 subjects completed the survey: 61 carrying the TTR-V50M variant and 24 caregivers or relatives. RESULTS: Our study revealed that, although most of the population studied had had prior contact with ATTRv through affected relatives, there was still a lack of information regarding disease diagnosis. Fear of the genetic test result and psychological issues were common in our population. Moreover, the disease had a stronger impact on the daily life of our patients than that of our asymptomatic carriers. Autonomic symptoms were the main source of burden for relatives and caregivers. CONCLUSION: Our survey results show high psychosocial burden associated with Val50Met-ATTRv in our area.


Assuntos
Neuropatias Amiloides Familiares , Estudos Transversais , Humanos , Pré-Albumina , Espanha
10.
Amyloid ; 27(4): 254-258, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32633140

RESUMO

BACKGROUND: Hereditary transthyretin amyloidosis (ATTRV30M) is a rare disease caused by amyloid deposition and characterized by a heterogeneous presentation. Anticipation (AC) is described as the decrease in age at onset (AO) within each generation. Our aim was to study AC in a large number of ATTRV30M kindred from Majorca (Spain), and gain further insight into parent-of-origin effects. METHODS: In a cohort of 262 subjects with ATTRV30M amyloidosis belonging to 51 families, we found 37 affected pairs. AO is defined as the age at the first symptom and AC (parent's age at disease onset minus that of the offspring) were calculated. Chi-square test, independent t-test and paired t-test were used for comparisons between groups. Association between AO of parents and offsprings were assessed by Pearson's correlation coefficient. RESULTS: Offspring mean AO was 16 years lower than that of the parents (p < .001) regardless of the sex of the parents and the offspring. AC occurred in 31 out of the 37 pairs, with no differences related to the sex of parents or offspring. There was a moderate correlation (r = 0.49; p < .001) between AO of the parents and that of the offsprings. CONCLUSION: AC was no uncommon in our cohort, and AO tended to decrease in successive generations.


Assuntos
Neuropatias Amiloides Familiares/genética , Mutação , Pré-Albumina/genética , Adulto , Idade de Início , Neuropatias Amiloides Familiares/epidemiologia , Neuropatias Amiloides Familiares/patologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Relações Pais-Filho , Espanha/epidemiologia
14.
Med. clín (Ed. impr.) ; 148(2): 63-66, ene. 2017. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-159190

RESUMO

Introducción y objetivo: La polineuropatía amiloidótica familiar causada por transtirretina) está caracterizada por la afectación del sistema nervioso. Las fibras nerviosas pequeñas se alteran de manera más precoz, por lo que la detección de su afectación tiene implicaciones serias en la historia natural de la enfermedad. Métodos: Estudio transversal, en el que se realizaron pruebas de detección de afectación de fibras nerviosas pequeñas en pacientes sintomáticos con TTR-PAF: Vibration, Touch Pressure (TP) y Heat Pain (HP). Los resultados se compararon con la exploración neurológica convencional y con un grupo de individuos sanos. Resultados: Se seleccionaron 15 pacientes con TTR-PAF en una fase precoz de la enfermedad (60% en estadio 1) y 13 individuos sanos. En la comparación entre ambos grupos no existían diferencias en cuanto a sexo, edad, peso, talla o IMC; sin embargo, en los test neurofisiológicos realizados se evidenciaron diferencias estadísticamente significativas: Vibration (p < 0,05), TP (p < 0,05) y HP (p < 0,05, excepto en la localización de antebrazo). Conclusiones: Los test neurofisiológicos realizados describen diferencias significativas entre ambos grupos, lo que podría permitir la detección del daño neurológico de forma más precoz que cuando se realiza una exploración neurológica convencional (AU)


Introduction and objective: Transthyretin-associated familial amyloid polyneuropathy (TTR-FAP) is a disease caused by the deposit of abnormal transthyretin on tissues, mainly nerves. Small nerve fibers are altered earlier during the course of the disease; hence, detection of their involvement may have serious consequences on the natural history of disease. Methods: A cross-sectional, observational study, was carried out on symptomatic patients, involving the conduct of several tests for small nerve fibers: Vibration, Touch Pressure (TP) and Heat Pain (HP). Results were compared with those obtained during a conventional neurological examination carried out on a group of healthy individuals. Results: Fifteen symptomatic patients were recruited at an early stage of the disease (60% stage 1), along with 13 healthy individuals, with both patient groups having similar epidemiological characteristics in terms of gender, age, weight, height or BMI. A comparison carried out between the neuropsychological tests performed revealed statistically significant differences: Vibration (P < .05), TP (P < .05) and HP (P < .05, except volar forearm). Conclusions: The neurophysiological tests performed revealed significant differences between both groups, allowing for an earlier detection of neurological injuries compared to conventional neurological examinations (AU)


Assuntos
Humanos , Neuropatias Amiloides Familiares/diagnóstico , Pré-Albumina/efeitos adversos , Técnicas de Diagnóstico Neurológico/instrumentação , Diagnóstico Precoce , Fibras Nervosas/fisiologia , Estudos Transversais , Reprodutibilidade dos Testes , Reprodutibilidade dos Testes , Condução Nervosa/fisiologia
15.
Med Clin (Barc) ; 148(2): 63-66, 2017 Jan 20.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27919414

RESUMO

INTRODUCTION AND OBJECTIVE: Transthyretin-associated familial amyloid polyneuropathy (TTR-FAP) is a disease caused by the deposit of abnormal transthyretin on tissues, mainly nerves. Small nerve fibers are altered earlier during the course of the disease; hence, detection of their involvement may have serious consequences on the natural history of disease. METHODS: A cross-sectional, observational study, was carried out on symptomatic patients, involving the conduct of several tests for small nerve fibers: Vibration, Touch Pressure (TP) and Heat Pain (HP). Results were compared with those obtained during a conventional neurological examination carried out on a group of healthy individuals. RESULTS: Fifteen symptomatic patients were recruited at an early stage of the disease (60% stage 1), along with 13 healthy individuals, with both patient groups having similar epidemiological characteristics in terms of gender, age, weight, height or BMI. A comparison carried out between the neuropsychological tests performed revealed statistically significant differences: Vibration (P<.05), TP (P<.05) and HP (P<.05, except volar forearm). CONCLUSIONS: The neurophysiological tests performed revealed significant differences between both groups, allowing for an earlier detection of neurological injuries compared to conventional neurological examinations.


Assuntos
Neuropatias Amiloides Familiares/diagnóstico , Diagnóstico Precoce , Exame Neurológico/métodos , Testes Neuropsicológicos , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Hum Mol Genet ; 25(19): 4157-4169, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27466199

RESUMO

Disrupted in Schizophrenia-1 (DISC1) has been associated with a broad spectrum of mental disorders. DISC1 is a multi-compartmentalized protein found in the cytoplasm, centrosome, nuclei and mostly enriched in mitochondria. In order to shed light on DISC1 mitochondrial function, we have studied its topology within the organelle. We show in here that in mammals DISC1 resides in the 'Mitochondrial contact site and Cristae Organizing system' (MICOS) complex, involved in cristae organization. DISC1 knockdown in SH-SY5Y cells causes MICOS disassembly and fragmentation of the mitochondrial morphology network. Moreover, DISC1 depleted cells have decreased mitochondrial DNA (mtDNA) content and steady state levels of oxidative phosphorylation (OXPHOS) subunits. As a consequence, OXPHOS complexes and supercomplexes are partially disassembled in DISC1 knockdown cells, which suffer severe bioenergetic defects, evidenced by impaired oxygen consumption, adenosine triphosphate synthesis and mitochondrial membrane potential. Transfection of recombinant full-length human DISC1 restores MICOS complex assembly and rescues OXPHOS function, meanwhile overexpression of the DISC1 truncated form Δ597-854, known to be pathogenic, fails to rescue the bioenergetic impairment caused by DISC1 knockdown. These results should contribute to reveal DISC1 physiological function and potential pathogenic role in severe mental illnesses.


Assuntos
Metabolismo Energético/genética , Proteínas do Tecido Nervoso/genética , Fosforilação Oxidativa , Esquizofrenia/genética , Linhagem Celular , Centrossomo/metabolismo , DNA Mitocondrial/genética , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Potencial da Membrana Mitocondrial/genética , Mitocôndrias/genética , Mitocôndrias/metabolismo , Complexos Multiproteicos/genética , Proteínas do Tecido Nervoso/biossíntese , Esquizofrenia/metabolismo , Esquizofrenia/patologia , Transfecção
17.
J Peripher Nerv Syst ; 21(4): 352-356, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27403623

RESUMO

The age of onset (AO) of hereditary ATTR amyloidosis (hATTR) is known to vary between populations, with differing characteristics reported according to AO in endemic/non-endemic foci. This was a retrospective study of patients with early AO (<50 years) and late AO (≥50 years) hATTR at our center in Mallorca. Data were collected on patient demographics, clinical disease manifestation, and physical symptoms. A total of 95 patients were analyzed, with mean follow-up of 9 years from diagnosis. The early AO group included 53 patients (33 male) and the late AO group included 42 patients (21 male). Neurologic involvement was the most common initial symptom, although it was significantly more frequent in the late AO vs. early AO group (p = 0.015). Autonomic involvement was observed in 26% of patients in the early AO group, but was rarely observed in the late AO group (5%). During follow up, cardiologic symptoms, renal involvement, and ophthalmologic symptoms were significantly more common in the late AO group (p < 0.05). This retrospective study demonstrates the variation in disease presentation and progression according to AO of hATTR at our Mallorcan center.


Assuntos
Neuropatias Amiloides Familiares , Mutação/genética , Pré-Albumina/genética , Adulto , Idade de Início , Idoso , Neuropatias Amiloides Familiares/complicações , Neuropatias Amiloides Familiares/epidemiologia , Neuropatias Amiloides Familiares/genética , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Metionina/genética , Pessoa de Meia-Idade , Estudos Retrospectivos , Espanha/epidemiologia , Valina/genética , Adulto Jovem
18.
EMBO Mol Med ; 8(1): 58-72, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26666268

RESUMO

CHCHD10-related diseases include mitochondrial DNA instability disorder, frontotemporal dementia-amyotrophic lateral sclerosis (FTD-ALS) clinical spectrum, late-onset spinal motor neuropathy (SMAJ), and Charcot-Marie-Tooth disease type 2 (CMT2). Here, we show that CHCHD10 resides with mitofilin, CHCHD3 and CHCHD6 within the "mitochondrial contact site and cristae organizing system" (MICOS) complex. CHCHD10 mutations lead to MICOS complex disassembly and loss of mitochondrial cristae with a decrease in nucleoid number and nucleoid disorganization. Repair of the mitochondrial genome after oxidative stress is impaired in CHCHD10 mutant fibroblasts and this likely explains the accumulation of deleted mtDNA molecules in patient muscle. CHCHD10 mutant fibroblasts are not defective in the delivery of mitochondria to lysosomes suggesting that impaired mitophagy does not contribute to mtDNA instability. Interestingly, the expression of CHCHD10 mutant alleles inhibits apoptosis by preventing cytochrome c release.


Assuntos
Apoptose/genética , Genoma Mitocondrial , Mitocôndrias/genética , Proteínas Mitocondriais/genética , Alelos , Linhagem Celular , Citocromos c/metabolismo , Reparo do DNA/efeitos dos fármacos , DNA Mitocondrial/análise , DNA Mitocondrial/metabolismo , Células HeLa , Humanos , Peróxido de Hidrogênio/toxicidade , Lisossomos/metabolismo , Potencial da Membrana Mitocondrial , Mitocôndrias/metabolismo , Doenças Mitocondriais/genética , Doenças Mitocondriais/patologia , Proteínas Mitocondriais/metabolismo , Mutação , Estresse Oxidativo/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real
19.
Nucleic Acids Res ; 42(15): 9573-87, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25081204

RESUMO

Calcium signals trigger the translocation of the Prz1 transcription factor from the cytoplasm to the nucleus. The process is regulated by the calcium-activated phosphatase calcineurin, which activates Prz1 thereby maintaining active transcription during calcium signalling. When calcium signalling ceases, Prz1 is inactivated by phosphorylation and exported to the cytoplasm. In budding yeast and mammalian cells, different kinases have been reported to counter calcineurin activity and regulate nuclear export. Here, we show that the Ca(2+)/calmodulin-dependent kinase Cmk1 is first phosphorylated and activated by the newly identified kinase CaMKK2 homologue, Ckk2, in response to Ca(2+). Then, active Cmk1 binds, phosphorylates and inactivates Prz1 transcription activity whilst at the same time cmk1 expression is enhanced by Prz1 in response to Ca(2+). Furthermore, Cdc25 phosphatase is also phosphorylated by Cmk1, inducing cell cycle arrest in response to an increase in Ca(2+). Moreover, cmk1 deletion shows a high tolerance to chronic exposure to Ca(2+), due to the lack of cell cycle inhibition and elevated Prz1 activity. This work reveals that Cmk1 kinase activated by the newly identified Ckk2 counteracts calcineurin function by negatively regulating Prz1 activity which in turn is involved in activating cmk1 gene transcription. These results are the first insights into Cmk1 and Ckk2 function in Schizosaccharomyces pombe.


Assuntos
Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Proteína Quinase Tipo 1 Dependente de Cálcio-Calmodulina/metabolismo , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Regulação Fúngica da Expressão Gênica , Proteínas de Schizosaccharomyces pombe/metabolismo , Fatores de Transcrição/metabolismo , Cálcio , Sinalização do Cálcio , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/química , Proteína Quinase Tipo 1 Dependente de Cálcio-Calmodulina/biossíntese , Proteína Quinase Tipo 1 Dependente de Cálcio-Calmodulina/genética , Proteínas Quinases Dependentes de Cálcio-Calmodulina/biossíntese , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Pontos de Checagem do Ciclo Celular , Retroalimentação Fisiológica , Deleção de Genes , Pressão Osmótica , Fosfoproteínas Fosfatases/metabolismo , Fosforilação , Schizosaccharomyces/enzimologia , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/biossíntese , Proteínas de Schizosaccharomyces pombe/química , Proteínas de Schizosaccharomyces pombe/genética , Fatores de Transcrição/genética
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