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1.
J Am Heart Assoc ; : e033558, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904226

RESUMO

BACKGROUND: The incidental use of statins during radiation therapy has been associated with a reduced long-term risk of developing atherosclerotic cardiovascular disease. We examined whether irradiation causes chronic vascular injury and whether short-term administration of statins during and after irradiation is sufficient to prevent chronic injury compared with long-term administration. METHODS AND RESULTS: C57Bl/6 mice were pretreated with pravastatin for 72 hours and then exposed to 12 Gy X-ray head-and-neck irradiation. Pravastatin was then administered either for an additional 24 hours or for 1 year. Carotid arteries were tested for vascular reactivity, altered gene expression, and collagen deposition 1 year after irradiation. Treatment with pravastatin for 24 hours after irradiation reduced the loss of endothelium-dependent vasorelaxation and protected against enhanced vasoconstriction. Expression of markers associated with inflammation (NFκB p65 [phospho-nuclear factor kappa B p65] and TNF-α [tumor necrosis factor alpha]) and with oxidative stress (NADPH oxidases 2 and 4) were lowered and subunits of the voltage and Ca2+ activated K+ BK channel (potassium calcium-activated channel subfamily M alpha 1 and potassium calcium-activated channel subfamily M regulatory beta subunit 1) in the carotid artery were modulated. Treatment with pravastatin for 1 year after irradiation completely reversed irradiation-induced changes. CONCLUSIONS: Short-term administration of pravastatin is sufficient to reduce chronic vascular injury at 1 year after irradiation. Long-term administration eliminates the effects of irradiation. These findings suggest that a prospective treatment strategy involving statins could be effective in patients undergoing radiation therapy. The optimal duration of treatment in humans has yet to be determined.

3.
J Urol ; 212(1): 153-164, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38593413

RESUMO

PURPOSE: Anterior urethral stricture disease (aUSD) is a complex, heterogeneous condition that is idiopathic in origin for most men. This gap in knowledge rarely affects the current management strategy for aUSD, as urethroplasty does not generally consider etiology. However, as we transition towards personalized, minimally invasive treatments for aUSD and begin to consider aUSD prevention strategies, disease pathophysiology will become increasingly important. The purpose of this study was to perform a deep phenotype of men undergoing anterior urethroplasty for aUSD. We hypothesized that unique biologic signatures and potential targets for intervention would emerge based on stricture presence/absence, stricture etiology, and the presence/absence of stricture inflammation. MATERIALS AND METHODS: Men with aUSD undergoing urethroplasty were recruited from one of 5 participating centers. Enrollees provided urethral stricture tissue and blood/serum on the day of surgery and completed patient-reported outcome measure questionnaires both pre- and postoperatively. The initial study had 3 aims: (1) to determine pediatric and adult subacute and repeated perineal trauma (SRPT) exposures using a study-specific SRPT questionnaire, (2) to determine the degree of inflammation and fibrosis in aUSD and peri-aUSD (normal urethra) tissue, and (3) to determine levels of systemic inflammatory and fibrotic cytokines. Two controls groups provided serum (normal vasectomy patients) and urethral tissue (autopsy patients). Cohorts were based on the presence/absence of stricture, by presumed stricture etiology (idiopathic, traumatic/iatrogenic, lichen sclerosus [LS]), and by the presence/absence of stricture inflammation. RESULTS: Of 138 enrolled men (120 tissue/serum; 18 stricture tissue only), 78 had idiopathic strictures, 33 had trauma-related strictures, and 27 had LS-related strictures. BMI, stricture length, and stricture location significantly differed between cohorts (P < .001 for each). The highest BMIs and the longest strictures were observed in the LS cohort. SRPT exposures did not significantly differ between etiology cohorts, with > 60% of each reporting low/mild risk. Stricture inflammation significantly differed between cohorts, with mild to severe inflammation present in 27% of trauma-related strictures, 54% of idiopathic strictures, and 48% of LS strictures (P = .036). Stricture fibrosis did not significantly differ between cohorts (P = .7). Three serum cytokines were significantly higher in patients with strictures compared to stricture-free controls: interleukin-9 (IL-9; P = .001), platelet-derived growth factor-BB (P = .004), and CCL5 (P = .01). No differences were observed in the levels of these cytokines based on stricture etiology. However, IL-9 levels were significantly higher in patients with inflamed strictures than in patients with strictures lacking inflammation (P = .019). Degree of stricture inflammation positively correlated with serum levels of IL-9 (Spearman's rho 0.224, P = .014). CONCLUSIONS: The most common aUSD etiology is idiopathic. Though convention has implicated SRPT as causative for idiopathic strictures, here we found that patients with idiopathic strictures had low SRPT rates that were similar to rates in patients with a known stricture etiology. Stricture and stricture-adjacent inflammation in idiopathic stricture were similar to LS strictures, suggesting shared pathophysiologic mechanisms. IL-9, platelet-derived growth factor-BB, and CCL5, which were elevated in patients with strictures, have been implicated in fibrotic conditions elsewhere in the body. Further work will be required to determine if this shared biologic signature represents a potential mechanism for an aUSD predisposition.


Assuntos
Fibrose , Inflamação , Fenótipo , Estreitamento Uretral , Humanos , Estreitamento Uretral/etiologia , Estreitamento Uretral/cirurgia , Estreitamento Uretral/patologia , Masculino , Pessoa de Meia-Idade , Inflamação/etiologia , Adulto , Uretra/cirurgia , Uretra/patologia , Idoso , Procedimentos Cirúrgicos Urológicos Masculinos/métodos , Medidas de Resultados Relatados pelo Paciente
4.
Urol Pract ; 10(6): 605-610, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37498314

RESUMO

INTRODUCTION: In 2014, the AUA published guidelines regarding the evaluation of cryptorchidism. This multi-institutional study aims to determine if these guidelines reduced the age of referral and the utilization of ultrasound in boys with cryptorchidism. We hypothesize that delayed referral continues, and utilization of ultrasound remains unchanged. METHODS: A retrospective review of boys referred for the evaluation of cryptorchidism was performed at 4 academic institutions, collecting data for 1 year prior (2013) and 2 nonconsecutive years following guideline creation (2015 and 2019). Across these time frames, we compared median ages at evaluation and surgery, and rates of patient comorbidities, orchiopexy, and preevaluation ultrasound. RESULTS: A total of 3,293 patients were included. The median age at initial pediatric urology evaluation in all cohorts was 39 months (IQR: 14-92 months). Following publication of the AUA Guidelines, there was no difference (P = .08) in the median age at first evaluation by a pediatric urologist between 2013 and 2015, and an increase (P = .03) between 2013 and 2019. Overall, 21.2% of patients received an ultrasound evaluation prior to referral, with no significant difference between 2013 and 2015 (P = .9) or 2019 (P = .5) cohorts. CONCLUSIONS: Our data suggest that, despite publication of the AUA Guidelines on evaluation and treatment of cryptorchidism, there has been no reduction in the age of urological evaluation or the utilization of imaging in boys with undescended testis. Finding alternative avenues to disseminate these evidence-based recommendations to referring providers and exploring barriers to guideline adherence is necessary to improve care for patients with cryptorchidism.


Assuntos
Criptorquidismo , Masculino , Humanos , Criança , Lactente , Pré-Escolar , Criptorquidismo/diagnóstico , Encaminhamento e Consulta , Orquidopexia/métodos , Estudos Retrospectivos , Ultrassonografia
5.
Front Cardiovasc Med ; 10: 1133315, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37404737

RESUMO

Background: The incidental use of statins during radiation therapy has been associated with a reduced long-term risk of developing atherosclerotic cardiovascular disease. However, the mechanisms by which statins protect the vasculature from irradiation injury remain poorly understood. Objectives: Identify the mechanisms by which the hydrophilic and lipophilic statins pravastatin and atorvastatin preserve endothelial function after irradiation. Methods: Cultured human coronary and umbilical vein endothelial cells irradiated with 4 Gy and mice subjected to 12 Gy head-and-neck irradiation were pretreated with statins and tested for endothelial dysfunction, nitric oxide production, oxidative stress, and various mitochondrial phenotypes at 24 and 240 h after irradiation. Results: Both pravastatin (hydrophilic) and atorvastatin (lipophilic) were sufficient to prevent the loss of endothelium-dependent relaxation of arteries after head-and-neck irradiation, preserve the production of nitric oxide by endothelial cells, and suppress the cytosolic reactive oxidative stress associated with irradiation. However, only pravastatin inhibited irradiation-induced production of mitochondrial superoxide; damage to the mitochondrial DNA; loss of electron transport chain activity; and expression of inflammatory markers. Conclusions: Our findings reveal some mechanistic underpinnings of the vasoprotective effects of statins after irradiation. Whereas both pravastatin and atorvastatin can shield from endothelial dysfunction after irradiation, pravastatin additionally suppresses mitochondrial injury and inflammatory responses involving mitochondria. Clinical follow-up studies will be necessary to determine whether hydrophilic statins are more effective than their lipophilic counterparts in reducing the risk of cardiovascular disease in patients undergoing radiation therapy.

6.
J Pediatr Urol ; 19(5): 608-618, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37331851

RESUMO

BACKGROUND: Decisional conflict surrounding the topic of circumcision in the newborn male is assumed in some parents but has not been quantified or qualified. It is known that parents often base their decision on cultural and social factors and that physician discussions do affect ultimate decision-making. Information on parents' decision-making surrounding newborn circumcision and ways to mitigate conflict or uncertainty around the decision-making process is needed to better counsel them appropriately. OBJECTIVES: To identify the presence or absence of decisional conflict in parents-to-be deciding whether or not to circumcise their child as well as to identify determinants of this conflict to direct future educational measures. STUDY DESIGN: Parents presenting to obstetrics clinic as well as contacted by institutional email were recruited using convenience sampling and completed the validated Decisional Conflict Scale (DCS). A smaller subset of subjects were recruited via institutional email to complete semi-structured interviews regarding the decision-making process and specifically uncertainty regarding the decision. Descriptive statistics and unpaired t tests were used for analysis of survey data. For interview data, an iterative, grounded theory methodology was used. RESULTS: 173 subjects completed the DCS. 12% of all participants had high decisional conflict. Intuitively, those who had not yet decided whether to circumcise had the highest proportion of high DCS (69%), followed by those who had decided to circumcise (9.3%) and those who had decided not to circumcise (1.7%). 24 subjects were interviewed, and based on their DCS scores and interview responses were classified as low, intermediate and high conflict. Three primary themes emerged delineating the high from low conflict groups. There were notable differences in the feelings of subjects regarding knowledge and feeling informed, the importance of particular values and clarity of the roles of these values in decision-making, and feelings of supported decision-making. These themes were used to create a visual model depicting the individual needs of each decision-maker (Fig. 1). DISCUSSION: This study highlights the need for decision support for parents that is not only information-based but focuses on values clarity and supported decision-making. This study provides a jumping-off point for creation of shared decision-making tools directed at individual needs. The limitations of this study are a single institution design and homogeneous population, so when designing materials, additional unrecognized needs will likely be identified. CONCLUSION: A small, but real proportion of parents-to-be experience significant uncertainty around the decision to circumcise their newborn boys. Identified needs of parents include feeling informed, feeling supported and clarification of important values related to the problem.


Assuntos
Circuncisão Masculina , Tomada de Decisões , Humanos , Recém-Nascido , Masculino , Emoções , Pais , Inquéritos e Questionários , Estados Unidos
7.
J Pediatr Urol ; 19(3): 295.e1-295.e8, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36707266

RESUMO

INTRODUCTION: Few pediatric urologists believe patients require a majority of the doses of opioids prescribed to them postoperatively. Seeking a better understanding of postoperative pain and analgesia in pediatric urology patients may help reduce opioid over prescription while still adequately managing postoperative pain. OBJECTIVE: We sought to better understand: 1) the postoperative pain levels experienced by pediatric urology patients, 2) the factors that correlate with postoperative pain and number of opioids consumed following pediatric urologic procedures, and 3) the patients who do not require opioids after surgery. STUDY DESIGN: Pediatric patients undergoing circumcision, inguinal hernia repair, orchidopexy, or hypospadias repair were eligible to participate. Patients were enrolled in the prospective cohort on the day of the procedure. For each of the first 7 postoperative days, patients' parents completed a text message-based questionnaire, quantifying their child's pain level and the doses of pain medication the child consumed. RESULTS: 165 participants were enrolled. 57 patients underwent circumcision, 54 underwent orchiopexy, 32 underwent hypospadias repair, and 22 underwent inguinal hernia repair. For all procedure types, pain scores (p < 0.01) and doses of oxycodone consumed were highest on postoperative day one and steadily declined thereafter. Overall, average 7-day pain score (2.02; 0.86-5.14) and doses of narcotics consumed (3.50; 0-5) were low. Patients in each surgical subgroup were prescribed narcotics in excess of what was consumed. There was an average excess of 10.9 doses (0-39.0) for hypospadias repair, 8.6 (1.0-30.0) for circumcision, 9.0 (3.0-21.0) for inguinal hernia repair, and 6.1 (0-22.0) for orchiopexy. DISCUSSION: Overall, reported pain scores and number of narcotics consumed were low regardless of surgery type. Opioids were overprescribed regardless of surgery type. CONCLUSIONS: Our findings indicate that level of pain and opioid use varies by procedure type, but that number of narcotics prescribed greatly exceeds number needed.


Assuntos
Hérnia Inguinal , Hipospadia , Urologia , Masculino , Humanos , Criança , Analgésicos Opioides/uso terapêutico , Estudos Prospectivos , Entorpecentes/uso terapêutico , Hérnia Inguinal/cirurgia , Hipospadia/tratamento farmacológico , Dor Pós-Operatória/tratamento farmacológico , Hábitos , Padrões de Prática Médica
8.
J Pediatr Urol ; 18(4): 466-468, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35717327

RESUMO

INTRODUCTION: A novel device, the cystomanometer, was developed for home bladder pressure monitoring in patients with neurogenic bladder. OBJECTIVE: To report initial experience and proof of concept with home use of the cystomanometer. STUDY DESIGN: Patients were asked to use the device twice daily for two weeks. RESULTS: Fourteen patients with neurogenic bladder were enrolled. DISCUSSION: The cystomanometer initially functioned well and transmitted data to a smartphone and to the hospital server. However, over 50% of devices broke. CONCLUSIONS: We report the first home use of a handheld electronic cystomanometer with wireless data transmission to a smartphone and hospital database.


Assuntos
Bexiga Urinaria Neurogênica , Humanos , Bexiga Urinaria Neurogênica/diagnóstico , Projetos Piloto , Urodinâmica , Bexiga Urinária
9.
J Pediatr Urol ; 18(3): 383-392, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35337731

RESUMO

INTRODUCTION: A bladder microbiome (urobiome) exists in adults. Data supports the effects of the adult urobiome on urinary tract health with associations between dysbiotic urobiomes and lower urinary tract disorders. Understanding urobiome origin is important since other microbiomes establish around birth and microbiome alterations are linked to disease development. However, the pediatric urobiome has not been well studied. OBJECTIVES: We sought to determine the age when the urobiome develops, compare the pediatric urobiome to microbiomes of adjacent urogenital niches, and compare the urobiomes between boys and girls and across age groups. STUDY DESIGN: Seventy-four children less than 18 years of age without recent antibiotic exposure were recruited, including 48 males and 26 females, aged 2 weeks to 209 months of age. Transurethral catheterized urine samples and samples from the perineum, urethra, vagina, and foreskin were collected. Specimens were assessed using the expanded quantitative urine culture protocol and by 16S rRNA gene sequencing. Dada2 was used to profile microbial compositions, and BLCA was used to identify microbial taxa. RESULTS: Bacteria were detected in 90.5% of urine samples and identified in children as young as 2 weeks of age. Microbial communities and compositions of the female bladder and other urogenital niches (urethra, perineum, and vagina) differed significantly by age. Lactobacillus predominated the bladder, urethral, and vaginal microbiomes in post-pubertal girls. Compared to female urinary microbiomes, those of males differed less substantially. Only perineal microbiomes differed significantly by age, whereas male urethral and foreskin microbiomes did not differ significantly. DISCUSSION: We identified that a urinary microbiome is established as early as infancy. In addition, the female urobiome changes throughout childhood, until the post-pubertal bacterial taxa becomes consistent with that seen in adult females. Whereas in boys, the urinary microbiome changed very little over time. In addition, the surrounding urogenital microbiomes differed less in boys as compared to females. Microbiomes established at a young age may have long-term influences on immune, metabolic, and neurobehavioral traits. The same may be true for the urobiome. Our study provides a foundation for future research to determine the influence of the pediatric urobiome on the development of urinary and even non-urinary disorders. CONCLUSIONS: A pediatric urobiome exists, with differences between males and females and can be detected at a young age with changes occurring throughout childhood. Similarities and differences are also seen between the pediatric urobiome and adjacent niches.


Assuntos
Microbiota , Adolescente , Adulto , Bactérias , Criança , Feminino , Humanos , Masculino , Microbiota/genética , Projetos Piloto , RNA Ribossômico 16S/genética , Uretra , Bexiga Urinária , Urina/microbiologia
10.
Transl Androl Urol ; 10(8): 3312-3316, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34532255

RESUMO

BACKGROUND: While the etiology for the upsurge in testosterone testing and prescriptions is likely multifactorial, increased direct-to-consumer marketing and the expansion of clinical care centers devoted to testosterone treatment likely play a role. Many of these centers require patients to report, in-person, on a regular basis for their injectable therapy and/or lab studies. The purpose of our study was to investigate barriers of care that patients receiving treatment for testosterone deficiency may be experiencing in the setting of COVID-19. METHODS: Our survey was posted on a closed Facebook support page for males currently receiving testosterone treatment and members of the group were invited to participate. The survey asked participants several questions related to how they received their injections, if they've experienced difficulties obtaining their injections due to COVID-19 restrictions, and about their interest in telemedicine services for their care. RESULTS: The majority of patients were able to receive their treatment despite barriers enforced by the pandemic. Of the 104 participants, almost half received their testosterone prescriptions from an outpatient clinic dedicated to testosterone replacement, while the other half received their therapy from a PCP, endocrinologist, or urologist. Only 5 patients (4.8%) noted difficulties obtaining their injections during this pandemic, 4 of which received their prescriptions from dedicated testosterone clinics, and the other from a PCP. Nearly 90% of respondents self-administered their testosterone therapy. With regards to telemedicine, 57.8% of patients have utilized the technology in some capacity, however 74.4% said that they would prefer to use telemedicine video services with a urologist or APP with expertise in andrology over in-person services. CONCLUSIONS: In our survey, the majority of the respondents have been able to receive their injectable testosterone therapy despite the ongoing pandemic. The majority of respondents self-administer their treatments, which may explain the lack of barriers. This study is the first of its kind to investigate the effect of a pandemic on the receipt of care for those being treated for testosterone deficiency with injectable testosterone.

11.
J Mol Cell Cardiol ; 87: 214-24, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26343497

RESUMO

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is an autosomal-dominant disease with mutations in genes encoding sarcomeric proteins. Previous findings suggest deregulation of the ubiquitin proteasome system (UPS) in HCM in humans and in a mouse model of HCM (Mybpc3-targeted knock-in (KI) mice). In this study we investigated transcript levels of several muscle-specific E3 ubiquitin ligases in KI mice and aimed at identifying novel protein targets. METHODS AND RESULTS: Out of 9 muscle-specific E3 ligases, Asb2ß was found with the lowest mRNA level in KI compared to wild-type (WT) mice. After adenoviral-mediated Asb2ß transduction of WT neonatal mouse cardiomyocytes with either a WT or inactive Asb2ß mutant, desmin was identified as a new target of Asb2ß by mass spectrometry, co-immunoprecipitation and immunoblotting. Immunofluorescence analysis revealed a co-localization of desmin with Asb2ß at the Z-disk of the sarcomere. Knock-down of Asb2ß in cardiomyocytes resulted in higher desmin protein levels. Furthermore, desmin levels were higher in ventricular samples of HCM mice and patients than controls. CONCLUSIONS: This study identifies desmin as a new Asb2ß target for proteasomal degradation in cardiomyocytes and suggests that accumulation of desmin could contribute to UPS impairment in HCM mice and patients.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Cardiomiopatia Hipertrófica/genética , Desmina/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Animais , Cardiomiopatia Hipertrófica/patologia , Desmina/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Camundongos , Mutação , Miocárdio/patologia , Miócitos Cardíacos/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Sarcômeros/metabolismo , Proteínas Supressoras da Sinalização de Citocina , Ubiquitina
12.
Eur J Heart Fail ; 15(3): 267-76, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23152444

RESUMO

AIMS: The transcription factor Islet-1 (ISL1) is a marker of cardiovascular progenitors and is essential for mammalian cardiogenesis. An ISL1 haplotype has recently been associated with congenital heart disease. In this study we evaluated whether ISL1 variants are associated with hypertrophic (HCM), dilated (DCM), arrhythmogenic right ventricular cardiomyopathy (ARVC), or with Emery-Dreifuss muscular dystrophy (EDMD). METHODS AND RESULTS: The six exon and intron boundaries of ISL1 were screened for genetic variants in a cohort of 454 index cases. Eleven exonic variants were identified in HCM, DCM, ARVC, and/or EDMD. Out of the five novel variants, two are located in the 5'-untranslated region, two are silent (p.Arg171Arg and p.Asn189Asn), and one is a missense (p.Asn252Ser). The latter was identified in the homozygous state in one DCM patient, and in the heterozygous state in 11 relatives, who did not present with DCM but often with cardiovascular features. This variant was found in one HCM patient also carrying a MYH7 mutation and in 3/96 North-African Caucasian control individuals, but was absent in 138 European Caucasian control individuals. We investigated the effect of the ISL1 wild type and p.Asn252Ser mutant on myocyte enhancer factor 2C (Mef2c) promoter activity, an established ISL1 target. Mef2c promoter activity was ∼4-fold higher in the presence of wild-type and ∼6-fold higher in the presence of mutant ISL1 in both HEK and CHO cells. CONCLUSION: This study describes a new gain-of-function p.Asn252Ser variant in the human ISL1 gene, which could potentially lead to greater activation of downstream targets involved in cardiac development, dilation, and hypertrophy.


Assuntos
Cardiomiopatias/genética , Proteínas com Homeodomínio LIM/genética , Proteínas de Domínio MADS/metabolismo , Distrofia Muscular de Emery-Dreifuss/genética , Fatores de Regulação Miogênica/metabolismo , Fatores de Transcrição/genética , Regiões 5' não Traduzidas/genética , Adulto , Animais , Displasia Arritmogênica Ventricular Direita/genética , Células CHO , Cardiomiopatia Dilatada/genética , Cardiomiopatia Hipertrófica/genética , Estudos de Casos e Controles , Estudos de Coortes , Cricetinae , Cricetulus , Éxons , Feminino , Técnicas de Transferência de Genes , Predisposição Genética para Doença , Células HEK293 , Heterozigoto , Homozigoto , Humanos , Íntrons , Fatores de Transcrição MEF2 , Masculino , Mutação de Sentido Incorreto , Linhagem , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas
13.
Cell Stem Cell ; 8(4): 376-88, 2011 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21474102

RESUMO

Transcription factor-based cellular reprogramming has opened the way to converting somatic cells to a pluripotent state, but has faced limitations resulting from the requirement for transcription factors and the relative inefficiency of the process. We show here that expression of the miR302/367 cluster rapidly and efficiently reprograms mouse and human somatic cells to an iPSC state without a requirement for exogenous transcription factors. This miRNA-based reprogramming approach is two orders of magnitude more efficient than standard Oct4/Sox2/Klf4/Myc-mediated methods. Mouse and human miR302/367 iPSCs display similar characteristics to Oct4/Sox2/Klf4/Myc-iPSCs, including pluripotency marker expression, teratoma formation, and, for mouse cells, chimera contribution and germline contribution. We found that miR367 expression is required for miR302/367-mediated reprogramming and activates Oct4 gene expression, and that suppression of Hdac2 is also required. Thus, our data show that miRNA and Hdac-mediated pathways can cooperate in a powerful way to reprogram somatic cells to pluripotency.


Assuntos
Reprogramação Celular/genética , MicroRNAs/fisiologia , Células-Tronco Pluripotentes/citologia , Animais , Humanos , Fator 4 Semelhante a Kruppel , Camundongos , Fatores de Transcrição/fisiologia
14.
Nature ; 466(7310): 1069-75, 2010 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-20740007

RESUMO

The causes of amyotrophic lateral sclerosis (ALS), a devastating human neurodegenerative disease, are poorly understood, although the protein TDP-43 has been suggested to have a critical role in disease pathogenesis. Here we show that ataxin 2 (ATXN2), a polyglutamine (polyQ) protein mutated in spinocerebellar ataxia type 2, is a potent modifier of TDP-43 toxicity in animal and cellular models. ATXN2 and TDP-43 associate in a complex that depends on RNA. In spinal cord neurons of ALS patients, ATXN2 is abnormally localized; likewise, TDP-43 shows mislocalization in spinocerebellar ataxia type 2. To assess the involvement of ATXN2 in ALS, we analysed the length of the polyQ repeat in the ATXN2 gene in 915 ALS patients. We found that intermediate-length polyQ expansions (27-33 glutamines) in ATXN2 were significantly associated with ALS. These data establish ATXN2 as a relatively common ALS susceptibility gene. Furthermore, these findings indicate that the TDP-43-ATXN2 interaction may be a promising target for therapeutic intervention in ALS and other TDP-43 proteinopathies.


Assuntos
Esclerose Lateral Amiotrófica/genética , Predisposição Genética para Doença , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Peptídeos/genética , Sequências Repetitivas de Aminoácidos/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Ataxinas , Linhagem Celular , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/toxicidade , Drosophila/efeitos dos fármacos , Drosophila/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios/patologia , Peptídeos/química , Fatores de Risco , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Adulto Jovem
15.
Eur Heart J ; 30(13): 1648-55, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19429631

RESUMO

AIMS: Familial hypertrophic cardiomyopathy (FHC) is caused by mutations in genes encoding sarcomeric proteins. Incomplete penetrance suggests the existence of modifier genes. Calmodulin (CaM) could be of importance given the key role of Ca(2+) for cardiac contractile function and growth. Any variant that affects CaM expression and/or function may impact on FHC clinical expression. METHODS AND RESULTS: We screened the promoter region of human calmodulin III gene (CALM3) and identified a new -34T>A polymorphism with a T-allele frequency of 0.70. The distribution of CALM3 genotypes differed in 180 unrelated FHC patients carrying a known FHC mutation compared with 134 controls, with higher TT-genotype frequency (0.73 vs. 0.51) and lower frequencies of AT- (0.24 vs. 0.37) and AA genotypes (0.03 vs. 0.11; P = 0.0005). To study whether the -34T>A polymorphism could play a modifier role, patients' relatives including both affected and healthy carriers were added. Affected carriers had a 0.56 times higher odds of carrying a T allele than healthy carriers (P = 0.053). We then investigated whether the -34T>A polymorphism affects the promoter activity using luciferase reporter vectors containing either CALM3-T or CALM3-A promoters. The activity of CALM3-T was lower than CALM3-A in HEK293 cells (1.00 +/- 0.19 vs. 2.31 +/- 0.13, P = 0.00001) and in cardiomyocytes (0.96 +/- 0.10 vs. 1.33 +/- 0.08, P = 0.00727). CONCLUSION: These data suggest that the -34T>A CALM3 polymorphism is a modifier gene for FHC, potentially by affecting expression level of CALM3 and therefore Ca(2+)-handling and development of hypertrophy.


Assuntos
Calmodulina/genética , Cardiomiopatia Hipertrófica Familiar/genética , Adulto , Distribuição por Idade , Idoso , Animais , Sequência de Bases , Calmodulina/metabolismo , Cardiomiopatia Hipertrófica Familiar/metabolismo , Feminino , Frequência do Gene , Genótipo , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Miócitos Cardíacos/metabolismo , Polimorfismo Genético , Regiões Promotoras Genéticas/genética , Ratos , Transfecção
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