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1.
Proc Natl Acad Sci U S A ; 118(33)2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34380738

RESUMO

Cardiomyogenesis, the process by which the body generates cardiomyocytes, is poorly understood. We have recently shown that Sfrp2 promotes cardiomyogenesis in vitro. The objective of this study was to determine if Sfrp2 would similarly promote cardiomyogenesis in vivo. To test this hypothesis, we tracked multipotent cKit(+) cells in response to Sfrp2 treatment. In control adult mice, multipotent cKit(+) cells typically differentiated into endothelial cells but not cardiomyocytes. In contrast, Sfrp2 switched the fate of these cells. Following Sfrp2 injection, multipotent cKit(+) cells differentiated solely into cardiomyocytes. Sfrp2-derived cardiomyocytes integrated into the myocardium and exhibited identical physiological properties to preexisting native cardiomyocytes. The ability of Sfrp2 to promote cardiomyogenesis was further supported by tracking EdU-labeled cells. In addition, Sfrp2 did not promote the formation of new cardiomyocytes when the cKit(+) cell population was selectively ablated in vivo using a diphtheria toxin receptor-diphtheria toxin model. Notably, Sfrp2-induced cardiomyogenesis was associated with significant functional improvements in a cardiac injury model. In summary, our study further demonstrates the importance of Sfrp2 in cardiomyogenesis.


Assuntos
Proteínas de Membrana/farmacologia , Infarto do Miocárdio/terapia , Animais , Cálcio/metabolismo , Diferenciação Celular , Regulação da Expressão Gênica , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Contração Miocárdica/fisiologia , Miócitos Cardíacos
2.
Am J Physiol Heart Circ Physiol ; 325(5): H965-H982, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37624101

RESUMO

With sparse treatment options, cardiac disease remains a significant cause of death among humans. As a person ages, mitochondria breakdown and the heart becomes less efficient. Heart failure is linked to many mitochondria-associated processes, including endoplasmic reticulum stress, mitochondrial bioenergetics, insulin signaling, autophagy, and oxidative stress. The roles of key mitochondrial complexes that dictate the ultrastructure, such as the mitochondrial contact site and cristae organizing system (MICOS), in aging cardiac muscle are poorly understood. To better understand the cause of age-related alteration in mitochondrial structure in cardiac muscle, we used transmission electron microscopy (TEM) and serial block facing-scanning electron microscopy (SBF-SEM) to quantitatively analyze the three-dimensional (3-D) networks in cardiac muscle samples of male mice at aging intervals of 3 mo, 1 yr, and 2 yr. Here, we present the loss of cristae morphology, the inner folds of the mitochondria, across age. In conjunction with this, the three-dimensional (3-D) volume of mitochondria decreased. These findings mimicked observed phenotypes in murine cardiac fibroblasts with CRISPR/Cas9 knockout of Mitofilin, Chchd3, Chchd6 (some members of the MICOS complex), and Opa1, which showed poorer oxidative consumption rate and mitochondria with decreased mitochondrial length and volume. In combination, these data show the need to explore if loss of the MICOS complex in the heart may be involved in age-associated mitochondrial and cristae structural changes.NEW & NOTEWORTHY This article shows how mitochondria in murine cardiac changes, importantly elucidating age-related changes. It also is the first to show that the MICOS complex may play a role in outer membrane mitochondrial structure.


Assuntos
Mitocôndrias , Miocárdio , Humanos , Masculino , Camundongos , Animais , Mitocôndrias/metabolismo , Miocárdio/metabolismo , Coração , Envelhecimento , Transdução de Sinais , Proteínas Mitocondriais/metabolismo
3.
BMC Cancer ; 23(1): 362, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081426

RESUMO

BACKGROUND: Isolated local failure (ILF) can occur in patients who initially receive definitive radiation therapy for prostate cancer. Salvage therapy for ILF includes high dose rate (HDR) brachytherapy. Prostate Specific Membrane Antigen (PSMA) Positron Emission Tomography (PET) can accurately detect ILF and can exclude extraprostatic disease. Lutetium-177 PSMA Radioligand Therapy (RLT) is a novel treatment for prostate cancer that can target prostate cancer accurately, while sparing radiation dose to normal tissues. METHODS: ROADSTER is a phase I/II randomized, single-institution study. Patients with an ILF of prostate cancer after definitive initial radiation therapy are eligible. The ILF will be confirmed with biopsy, magnetic resonance imaging (MRI) and PSMA PET. Patients will be randomized between HDR brachytherapy in two fractions (a standard of care salvage treatment at our institution) (cohort 1) or one treatment of intravenous Lutetium-177 PSMA RLT, followed by one fraction of HDR brachytherapy (cohort 2). The primary endpoints for the phase I portion of the study (n = 12) will be feasibility, defined as 10 or more patients completing the study protocol within 24 months of study activation; and safety, defined as zero or one patients in cohort 2 experiencing grade 3 or higher toxicity in the first 6 months post-treatment. If feasibility and safety are achieved, the study will expand to a phase II study (n = 30 total) where preliminary efficacy data will be evaluated. Secondary endpoints include changes in prostate specific antigen levels, acute toxicity, changes in quality of life, and changes in translational biomarkers. Translational endpoints will include interrogation of blood, urine, and tissue for markers of DNA damage and immune activation with each treatment. DISCUSSION: ROADSTER explores a novel salvage therapy for ILF after primary radiotherapy with combined Lutetium-177 PSMA RLT and HDR brachytherapy. The randomized phase I/II design will provide a contemporaneous patient population treated with HDR alone to facilitate assessment of feasibility, tolerability, and biologic effects of this novel therapy. TRIAL REGISTRATION: NCT05230251 (ClinicalTrials.gov).


Assuntos
Braquiterapia , Neoplasias da Próstata , Humanos , Masculino , Braquiterapia/efeitos adversos , Braquiterapia/métodos , Próstata/patologia , Antígeno Prostático Específico , Neoplasias da Próstata/patologia , Qualidade de Vida , Tomografia Computadorizada por Raios X
4.
Nephrol Dial Transplant ; 37(7): 1366-1374, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34245292

RESUMO

BACKGROUND: Chronic kidney disease is closely related to a high risk of death and disability, poor physical performance and frailty. The main objective of this research was to analyse how intradialytic administration of a non-immersive virtual reality (VR) exercise programme would affect physical function and adherence to exercise in these patients. METHODS: A total of 56 individuals participated in two 12-week periods in a crossover randomized controlled trial. Each patient underwent a functional capacity evaluation before and after each study period. The functional tests administered included the 4-m gait speed test, Short Physical Performance Battery (SPPB), timed up-and-go (TUG) test, one-legged stance test (OLST) for balance, sit-to-stand 10 (STS-10) and sit-to-stand 60 (STS-60) tests and 6-min walking test (6MWT). Adherence to the exercise programme was also recorded. To assess the effect of VR exercise on the functional test outcomes over time, the patients were analysed using a two-way repeated-measures analysis of variance with time and treatment as the within-participant factors. RESULTS: By the end of the 12 weeks of exercise, compared with the control period, 33 participants showed significant change in physical function as measured through the 4-m gait speed test (0.14 m/s), SPPB (1.2 points), TUG (-1.7 s), OLST (7.1 s), STS-10 (-5.8 s), STS-60 (5 repetitions) and 6MWT (85.2 m), with adherence rates exceeding 70%. There were no changes in the biochemical data or in the medications in the period of the study. CONCLUSION: An intradialytic non-immersive VR exercise programme improves patient physical function.


Assuntos
Jogos Eletrônicos de Movimento , Velocidade de Caminhada , Exercício Físico , Terapia por Exercício , Marcha , Humanos , Desempenho Físico Funcional
5.
Infection ; 49(5): 919-926, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33948875

RESUMO

OBJECTIVE: To evaluate the usefulness of ultrasound examination in patients with just a serological diagnosis of schistosomiasis but no other evidence of active infection. METHODS: 346 sub-Saharan patients with possible schistosomiasis that presented at a Tropical Medicine Unit between 2008 and 2019 were retrospectively selected. Possible schistosomiasis was considered in those patients with a positive serology for schistosomasis in the absence of direct microbiological isolates, hematuria and/or eosinophilia. Data from ultrasound examinations before and after treatment with praziquantel were collected and categorized following the World Health Organization-Niamey score to standardize the use of ultrasonography for the assessment of schistosomiasis-related morbidity. RESULTS: Ultrasound examinations were abnormal in only ten patients (2.89%). Main findings were focal thickening of the bladder wall (n = 6), ureteral dilatation (n = 3) and grade I hydronephrosis (n = 1). No malignant lesions, hepatic lesions nor hepatobiliary related disorders were found. After treatment, the S. haematobium global score (5 vs 3.4, p = 0.06) and the urinary bladder score (2 vs 1, p = 0.059) showed a trend towards improvement after treatment. In three patients the score after treatment dropped to 0, and in another three it remained the same although with signs of improvement. No worsening of the score was observed in any case. CONCLUSION: For those patients with a diagnosis of schistosomiasis based solely in a positive serology, the ultrasound examination could safely be spared due to the low prevalence of pathological findings and its response to treatment anyway.


Assuntos
Esquistossomose Urinária , África Subsaariana/epidemiologia , Humanos , Praziquantel , Estudos Retrospectivos , Esquistossomose Urinária/diagnóstico por imagem , Esquistossomose Urinária/tratamento farmacológico , Ultrassonografia
6.
Am J Physiol Renal Physiol ; 318(2): F285-F297, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31760770

RESUMO

Juxtaglomerular (JG) cells, major sources of renin, differentiate from metanephric mesenchymal cells that give rise to JG cells or a subset of smooth muscle cells of the renal afferent arteriole. During periods of dehydration and salt deprivation, renal mesenchymal stromal cells (MSCs) differentiate from JG cells. JG cells undergo expansion and smooth muscle cells redifferentiate to express renin along the afferent arteriole. Gene expression profiling comparing resident renal MSCs with JG cells indicates that the transcription factor Sox6 is highly expressed in JG cells in the adult kidney. In vitro, loss of Sox6 expression reduces differentiation of renal MSCs to renin-producing cells. In vivo, Sox6 expression is upregulated after a low-Na+ diet and furosemide. Importantly, knockout of Sox6 in Ren1d+ cells halts the increase in renin-expressing cells normally seen during a low-Na+ diet and furosemide as well as the typical increase in renin. Furthermore, Sox6 ablation in renin-expressing cells halts the recruitment of smooth muscle cells along the afferent arteriole, which normally express renin under these conditions. These results support a previously undefined role for Sox6 in renin expression.


Assuntos
Arteríolas/metabolismo , Sistema Justaglomerular/irrigação sanguínea , Células-Tronco Mesenquimais/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Renina/metabolismo , Fatores de Transcrição SOXD/metabolismo , Animais , Arteríolas/efeitos dos fármacos , Pressão Sanguínea , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Dieta Hipossódica , Diuréticos/farmacologia , Furosemida/farmacologia , Regulação da Expressão Gênica , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Renina/genética , Fatores de Transcrição SOXD/deficiência , Fatores de Transcrição SOXD/genética , Transdução de Sinais
7.
Emerg Infect Dis ; 25(2): 349-352, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30666945

RESUMO

In a screening program, we detected submicroscopic malaria in 8.9% of recent migrants to Spain from sub-Saharan Africa. Hemoglobinopathies and filarial infection occurred more frequently in newly arrived migrants with submicroscopic malaria than in those without. Our findings could justify systematic screening in immigrants and recent travelers from malaria-endemic areas.


Assuntos
Malária/epidemiologia , Malária/parasitologia , Carga Parasitária , Migrantes , África Subsaariana/epidemiologia , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Contagem de Leucócitos , Malária/diagnóstico , Malária/transmissão , Programas de Rastreamento , Microscopia , Vigilância da População , Estudos Retrospectivos , Espanha/epidemiologia
8.
J Magn Reson Imaging ; 49(5): 1409-1419, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30430700

RESUMO

BACKGROUND: Overtreatment of prostate cancer (PCa) is a healthcare issue. Development of noninvasive imaging tools for improved characterization of prostate lesions might reduce overtreatment. PURPOSE: To measure the distribution of tissue sodium concentration (TSC), proton T2 -weighted signal, and apparent diffusion coefficient (ADC) values in human PCa and to test the presence of a correlation between regional differences in imaging metrics and the Gleason grade of lesions determined from histopathology. STUDY TYPE: Cross-sectional. SUBJECTS: Ten men with biopsy-proven PCa. SEQUENCES/FIELD STRENGTH: Sodium, proton T2 -weighted, and diffusion-weighted MRI data were acquired using Broad-Band 3D-Fast-Gradient-Recalled, 3D Cube (Isotropic 3D-Fast-Turbo-Spin-Echo acquisition) and 2D Spin-Echo sequences, respectively, with a 3.0T MR scanner. ASSESSMENT: All imaging data were coregistered to Gleason-graded postprostatectomy histology, as the standard for prostate cancer lesion characterization. Regional TSC and T2 data were assessed using percent changes from healthy tissue of the same patient (denoted ΔTSC, ΔT2 ). STATISTICS: Differences in ΔTSC, ADC, and ΔT2 as a function of Gleason score were analyzed for each imaging contrast using a one-way analysis of variance or a nonparametric t-test. Correlations between imaging data measures and Gleason score were assessed using a Spearman's ranked correlation. RESULTS: Evaluation of the correlation of ΔTSC, ADC, and ΔT2 datasets with Gleason scoring revealed that only the correlation between ΔTSC and Gleason score was statistically significant (rs = 0.791, p < 0.01), whereas the correlations of ADC and ΔT2 with Gleason score were not (rs = -0.306, p = 0.079 and r s = -0.069, p = 0.699, respectively). In addition, all individual patients showed monotonically increasing ΔTSC with Gleason score. DATA CONCLUSION: The results of this preliminary study suggest that changes in TSC, assessed by sodium MRI, has utility as a noninvasive imaging assay to accurately characterize PCa lesions. Sodium MRI may provide useful complementary information on mpMRI, which may assist the decision-making of men choosing either active surveillance or treatment. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:1409-1419.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Sódio
9.
J Mol Cell Cardiol ; 123: 64-74, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30171847

RESUMO

There is much interest over resident c-Kit(+) cells in tissue regeneration. Their role in cardiac regeneration has been controversial. In this study we aim to understand the in vivo behavior of cardiac c-Kit(+) cells at baseline and after myocardial infarction and in response to Sfrp2. This approach can accurately study the in vivo transcript expressions of these cells in temporal response to injury and overcomes the limitations of the in vitro approach. RNA-seq was performed with c-Kit(+) cells and cardiomyocytes from healthy non-injured mice as well as c-Kit(+) cells from 1 day post-MI and 12 days post-MI mice. When compared to in vivo c-Kit(+) cells isolated from a healthy non-injured mouse heart, cardiomyocytes were enriched in transcripts that express anion channels, cation channels, developmental/differentiation pathway components, as well as proteins that inhibit canonical Wnt/ß-catenin signaling. Myocardial infarction (MI) induced in vivo c-Kit(+) cells to transiently adopt the cardiomyocyte-specific signature: expression of a number of cardiomyocyte-specific transcripts was maximal 1 day post-MI and declined by 12 days post-MI. We next studied the effect of ß-catenin inhibition on in vivo c-Kit(+) cells by administering the Wnt inhibitor Sfrp2 into the infarct border zone. Sfrp2 both enhanced and sustained cardiomyocyte-specific gene expression in the in vivo c-Kit(+) cells: expression of cardiomyocyte-specific transcripts was higher and there was no decline in expression by 12 days post-MI. Further analysis of the biology of c-Kit(+) cells identified that culture induced a significant and irreversible change in their molecular signature raising questions about reliability of in vitro studies. Our findings provide evidence that MI induces in vivo c-Kit(+) cells to adopt transiently a cardiomyocyte-specific pattern of gene expression, and Sfrp2 further enhances and induces sustained gene expression. Our approach is important for understanding c-Kit(+) cells in cardiac regeneration and also has broad implications in the investigation of in vivo resident stem cells in other areas of tissue regeneration.


Assuntos
Traumatismos Cardíacos/etiologia , Traumatismos Cardíacos/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , beta Catenina/antagonistas & inibidores , beta Catenina/metabolismo , Animais , Diferenciação Celular , Biologia Computacional/métodos , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Canais Iônicos/genética , Canais Iônicos/metabolismo , Camundongos , Camundongos Knockout , Mioblastos/citologia , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Especificidade de Órgãos/genética , Via de Sinalização Wnt
11.
Stem Cells ; 35(7): 1687-1703, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28472853

RESUMO

Coenzyme Q10 (CoQ10 ) plays a crucial role in mitochondria as an electron carrier within the mitochondrial respiratory chain (MRC) and is an essential antioxidant. Mutations in genes responsible for CoQ10 biosynthesis (COQ genes) cause primary CoQ10 deficiency, a rare and heterogeneous mitochondrial disorder with no clear genotype-phenotype association, mainly affecting tissues with high-energy demand including brain and skeletal muscle (SkM). Here, we report a four-year-old girl diagnosed with minor mental retardation and lethal rhabdomyolysis harboring a heterozygous mutation (c.483G > C (E161D)) in COQ4. The patient's fibroblasts showed a decrease in [CoQ10 ], CoQ10 biosynthesis, MRC activity affecting complexes I/II + III, and respiration defects. Bona fide induced pluripotent stem cell (iPSCs) lines carrying the COQ4 mutation (CQ4-iPSCs) were generated, characterized and genetically edited using the CRISPR-Cas9 system (CQ4ed -iPSCs). Extensive differentiation and metabolic assays of control-iPSCs, CQ4-iPSCs and CQ4ed -iPSCs demonstrated a genotype association, reproducing the disease phenotype. The COQ4 mutation in iPSC was associated with CoQ10 deficiency, metabolic dysfunction, and respiration defects. iPSC differentiation into SkM was compromised, and the resulting SkM also displayed respiration defects. Remarkably, iPSC differentiation in dopaminergic or motor neurons was unaffected. This study offers an unprecedented iPSC model recapitulating CoQ10 deficiency-associated functional and metabolic phenotypes caused by COQ4 mutation. Stem Cells 2017;35:1687-1703.


Assuntos
Ataxia/genética , Deficiência Intelectual/genética , Mitocôndrias/genética , Doenças Mitocondriais/genética , Proteínas Mitocondriais/genética , Debilidade Muscular/genética , Rabdomiólise/genética , Ubiquinona/análogos & derivados , Ubiquinona/deficiência , Ataxia/enzimologia , Ataxia/patologia , Sistemas CRISPR-Cas , Diferenciação Celular , Pré-Escolar , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/metabolismo , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Evolução Fatal , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Edição de Genes/métodos , Expressão Gênica , Genes Letais , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Deficiência Intelectual/enzimologia , Deficiência Intelectual/patologia , Mitocôndrias/enzimologia , Mitocôndrias/patologia , Doenças Mitocondriais/enzimologia , Doenças Mitocondriais/patologia , Proteínas Mitocondriais/deficiência , Neurônios Motores/citologia , Neurônios Motores/metabolismo , Debilidade Muscular/enzimologia , Debilidade Muscular/patologia , Cultura Primária de Células , Rabdomiólise/enzimologia , Rabdomiólise/patologia , Ubiquinona/genética
12.
Circ Res ; 118(1): 95-107, 2016 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-26837742

RESUMO

In the past decade, substantial evidence supports the paradigm that stem cells exert their reparative and regenerative effects, in large part, through the release of biologically active molecules acting in a paracrine fashion on resident cells. The data suggest the existence of a tissue microenvironment where stem cell factors influence cell survival, inflammation, angiogenesis, repair, and regeneration in a temporal and spatial manner.


Assuntos
Cardiologia/tendências , Doenças Cardiovasculares/terapia , Comunicação Parácrina/fisiologia , Medicina Regenerativa/tendências , Animais , Cardiologia/métodos , Doenças Cardiovasculares/diagnóstico , Diferenciação Celular/fisiologia , Humanos , Miócitos Cardíacos/fisiologia , Miócitos Cardíacos/transplante , Medicina Regenerativa/métodos , Transplante de Células-Tronco/métodos , Transplante de Células-Tronco/tendências
13.
J Physiol ; 594(24): 7229-7248, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27570189

RESUMO

KEY POINTS: Biotin, a vitamin whose main role is as a coenzyme for carboxylases, accumulates at unusually large amounts within cells of the carotid body (CB). In biotin-deficient rats biotin rapidly disappears from the blood; however, it remains at relatively high levels in CB glomus cells. The CB contains high levels of mRNA for SLC5a6, a biotin transporter, and SLC19a3, a thiamine transporter regulated by biotin. Animals with biotin deficiency exhibit pronounced metabolic lactic acidosis. Remarkably, glomus cells from these animals have normal electrical and neurochemical properties. However, they show a marked decrease in the size of quantal dopaminergic secretory events. Inhibitors of the vesicular monoamine transporter 2 (VMAT2) mimic the effect of biotin deficiency. In biotin-deficient animals, VMAT2 protein expression decreases in parallel with biotin depletion in CB cells. These data suggest that dopamine transport and/or storage in small secretory granules in glomus cells depend on biotin. ABSTRACT: Biotin is a water-soluble vitamin required for the function of carboxylases as well as for the regulation of gene expression. Here, we report that biotin accumulates in unusually large amounts in cells of arterial chemoreceptors, carotid body (CB) and adrenal medulla (AM). We show in a biotin-deficient rat model that the vitamin rapidly disappears from the blood and other tissues (including the AM), while remaining at relatively high levels in the CB. We have also observed that, in comparison with other peripheral neural tissues, CB cells contain high levels of SLC5a6, a biotin transporter, and SLC19a3, a thiamine transporter regulated by biotin. Biotin-deficient rats show a syndrome characterized by marked weight loss, metabolic lactic acidosis, aciduria and accelerated breathing with normal responsiveness to hypoxia. Remarkably, CB cells from biotin-deficient animals have normal electrophysiological and neurochemical (ATP levels and catecholamine synthesis) properties; however, they exhibit a marked decrease in the size of quantal catecholaminergic secretory events, which is not seen in AM cells. A similar differential secretory dysfunction is observed in CB cells treated with tetrabenazine, a selective inhibitor of the vesicular monoamine transporter 2 (VMAT2). VMAT2 is highly expressed in glomus cells (in comparison with VMAT1), and in biotin-deficient animals VMAT2 protein expression decreases in parallel with the decrease of biotin accumulated in CB cells. These data suggest that biotin has an essential role in the homeostasis of dopaminergic transmission modulating the transport and/or storage of transmitters within small secretory granules in glomus cells.


Assuntos
Biotina/metabolismo , Corpo Carotídeo/metabolismo , Dopamina/metabolismo , Trifosfato de Adenosina/metabolismo , Medula Suprarrenal/metabolismo , Animais , Artérias/metabolismo , Biotina/sangue , Biotina/deficiência , Células Cromafins/metabolismo , Exocitose , Hipóxia/fisiopatologia , Ácido Láctico/sangue , Ratos Wistar , Gânglio Cervical Superior/metabolismo , Tetrabenazina/farmacologia , Proteínas Vesiculares de Transporte de Monoamina/antagonistas & inibidores , Proteínas Vesiculares de Transporte de Monoamina/metabolismo
14.
J Neurochem ; 136(2): 373-87, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26500044

RESUMO

Despite the different animal models of Parkinson's disease developed during the last years, they still present limitations modelling the slow and progressive process of neurodegeneration. Here, we undertook a histological, neurochemical and behavioural analysis of a new chronic parkinsonian mouse model generated by the subcutaneous administration of low doses of MPTP (20 mg/kg, 3 times per week) for 3 months, using both young adult and aged mice. The MPTP-induced nigrostriatal neurodegeneration was progressive and was accompanied by a decrease in striatal dopamine levels and motor impairment. We also demonstrated the characteristic neuroinflammatory changes (microglial activation and astrogliosis) associated with the neurodegenerative process. Aged animals showed both a faster time course of neurodegeneration and an altered neuroinflammatory response. The long-term systemic application of low MPTP doses did not induce any increase in mortality in either young adult or aged mice and better resembles the slow evolution of the neurodegenerative process. This treatment could be useful to model different stages of Parkinson's disease, providing a better understanding of the pathophysiology of the disease and facilitating the testing of both protective and restorative treatments. Here, we show a new chronic and progressive parkinsonian mouse model, in young and aged mice. This model produces a stable degeneration of the dopaminergic nigrostriatal pathway, continuous neuroinflammatory reaction and motor deficits. Aged animals showed a faster neurodegeneration and an altered neuroinflammatory response. This treatment could be useful to model different stages of PD and to test both protective and restorative therapeutic approaches.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Envelhecimento , Intoxicação por MPTP , Fatores Etários , Animais , Catecolaminas/metabolismo , Doença Crônica , Corpo Estriado/patologia , Modelos Animais de Doenças , Progressão da Doença , Relação Dose-Resposta a Droga , Inflamação/etiologia , Intoxicação por MPTP/induzido quimicamente , Intoxicação por MPTP/patologia , Intoxicação por MPTP/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Força Muscular/efeitos dos fármacos , Degeneração Neural/etiologia , Proteínas do Tecido Nervoso/metabolismo , Desempenho Psicomotor/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/metabolismo
15.
Circ Res ; 115(12): 1007-16, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25296984

RESUMO

RATIONALE: Cardiac progenitor cells (CPCs) are thought to differentiate into the major cell types of the heart: cardiomyocytes, smooth muscle cells, and endothelial cells. We have recently identified ABI family, member 3 (NESH) binding protein (Abi3bp) as a protein important for mesenchymal stem cell biology. Because CPCs share several characteristics with mesenchymal stem cells, we hypothesized that Abi3bp would similarly affect CPC differentiation and proliferation. OBJECTIVE: To determine whether Abi3bp regulates CPC proliferation and differentiation. METHODS AND RESULTS: In vivo, genetic ablation of the Abi3bp gene inhibited CPC differentiation, whereas CPC number and proliferative capacity were increased. This correlated with adverse recovery after myocardial infarction. In vitro, CPCs, either isolated from Abi3bp knockout mice or expressing an Abi3bp shRNA construct, displayed a higher proliferative capacity and, under differentiating conditions, reduced expression of both early and late cardiomyocyte markers. Abi3bp controlled CPC differentiation via integrin-ß1, protein kinase C-ζ, and v-akt murine thymoma viral oncogene homolog. CONCLUSIONS: We have identified Abi3bp as a protein important for CPC differentiation and proliferation.


Assuntos
Proteínas de Transporte/metabolismo , Diferenciação Celular , Proliferação de Células , Células-Tronco Mesenquimais/metabolismo , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Proteínas de Transporte/genética , Células Cultivadas , Modelos Animais de Doenças , Integrina beta1/metabolismo , Isoenzimas/metabolismo , Masculino , Células-Tronco Mesenquimais/patologia , Camundongos Knockout , Contração Miocárdica , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/patologia , Proteína Quinase C/metabolismo , Proteína Quinase C-theta , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Recuperação de Função Fisiológica , Regeneração , Transdução de Sinais , Volume Sistólico , Fatores de Tempo , Transfecção
16.
J Am Soc Nephrol ; 26(12): 2953-62, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25855778

RESUMO

Inappropriate activation of the type 1A angiotensin (AT1A) receptor contributes to the pathogenesis of hypertension and its associated complications. To define the role for actions of vascular AT1A receptors in BP regulation and hypertension pathogenesis, we generated mice with cell-specific deletion of AT1A receptors in smooth muscle cells (SMKO mice) using Loxp technology and Cre transgenes with robust expression in both conductance and resistance arteries. We found that elimination of AT1A receptors from vascular smooth muscle cells (VSMCs) caused a modest (approximately 7 mmHg) yet significant reduction in baseline BP and exaggerated sodium sensitivity in mice. Additionally, the severity of angiotensin II (Ang II)-dependent hypertension was dramatically attenuated in SMKO mice, and this protection against hypertension was associated with enhanced urinary excretion of sodium. Despite the lower BP, acute vasoconstrictor responses to Ang II in the systemic vasculature were largely preserved (approximately 80% of control levels) in SMKO mice because of exaggerated activity of the sympathetic nervous system rather than residual actions of AT1B receptors. In contrast, Ang II-dependent responses in the renal circulation were almost completely eliminated in SMKO mice (approximately 5%-10% of control levels). These findings suggest that direct actions of AT1A receptors in VSMCs are essential for regulation of renal blood flow by Ang II and highlight the capacity of Ang II-dependent vascular responses in the kidney to effect natriuresis and BP control.


Assuntos
Pressão Sanguínea/fisiologia , Natriurese/fisiologia , Receptor Tipo 1 de Angiotensina/fisiologia , Circulação Renal/fisiologia , Antagonistas Adrenérgicos alfa/farmacologia , Angiotensina II/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Catecolaminas/urina , Hipertensão/induzido quimicamente , Hipertensão/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/fisiologia , Natriurese/efeitos dos fármacos , Fentolamina/farmacologia , Receptor Tipo 1 de Angiotensina/genética , Circulação Renal/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiopatologia , Vasoconstrição/efeitos dos fármacos , Vasoconstrição/fisiologia , Vasoconstritores/farmacologia
17.
Eur J Anaesthesiol ; 32(10): 681-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26225497

RESUMO

BACKGROUND: Renal failure affects the pharmacology of nondepolarizing neuromuscular blockers making recovery of neuromuscular function unpredictable. Sugammadex antagonises rocuronium-induced neuromuscular blockade by encapsulating rocuronium, creating a stable complex molecule that is mainly excreted by the kidneys. Previous studies suggest that sugammadex is effective in reversing moderate neuromuscular block in the presence of renal failure, but no data are available regarding reversal of profound neuromuscular block in patients with renal failure. OBJECTIVE: The objective of this study is to compare the efficacy and safety of sugammadex in reversing profound neuromuscular block induced by rocuronium in patients with end-stage renal disease and those with normal renal function. DESIGN: A prospective clinical trial. SETTING: Two university hospitals, from 1 October 2011 to 31 January 2012. PATIENTS: Forty patients undergoing kidney transplant: 20 with renal failure [creatinine clearance (ClCr) <30 ml min] and 20 control patients (ClCr >90 ml min). INTERVENTION: Neuromuscular monitoring was performed by acceleromyography and train-of-four (TOF) stimulation. Profound neuromuscular block (posttetanic count, one to three responses) was maintained during surgery. Sugammadex 4 mg kg was administered on completion of skin closure. Recovery of the TOF ratio to 0.9 was recorded. Monitoring of neuromuscular function continued in the postanesthesia care unit for a further 2 h. MAIN OUTCOME MEASURES: The efficacy of sugammadex was evaluated by the time taken for the TOF ratio to recover to 0.9. The safety of sugammadex was assessed by monitoring for recurrence of neuromuscular block every 15 min for 2 h. Secondary variables were time to recovery of TOF ratio to 0.7 and 0.8. RESULTS: After sugammadex administration, the mean time for recovery of the TOF ratio to 0.9 was prolonged in the renal failure group (5.6 ±â€Š3.6 min) compared with the control group (2.7 ±â€Š1.3 min, P = 0.003). No adverse events or evidence of recurrence of neuromuscular block were observed. CONCLUSION: In patients with renal failure, sugammadex (4 mg kg) effectively and safely reversed profound rocuronium induced neuromuscular block, but the recovery was slower than healthy patients. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT01785758.


Assuntos
Androstanóis/administração & dosagem , Falência Renal Crônica/fisiopatologia , Bloqueio Neuromuscular/métodos , gama-Ciclodextrinas/administração & dosagem , Acelerometria , Adulto , Estudos de Casos e Controles , Feminino , Hospitais Universitários , Humanos , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Monitoração Neuromuscular , Fármacos Neuromusculares não Despolarizantes/administração & dosagem , Estudos Prospectivos , Rocurônio , Sugammadex , Fatores de Tempo , gama-Ciclodextrinas/efeitos adversos
18.
BMC Bioinformatics ; 15: 409, 2014 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-25519981

RESUMO

BACKGROUND: Dynamic Flux Balance Analysis (DFBA) is a dynamic simulation framework for biochemical processes. DFBA can be performed using different approaches such as static optimization (SOA), dynamic optimization (DOA), and direct approaches (DA). Few existing simulators address the theoretical and practical challenges of nonunique exchange fluxes or infeasible linear programs (LPs). Both are common sources of failure and inefficiencies for these simulators. RESULTS: DFBAlab, a MATLAB-based simulator that uses the LP feasibility problem to obtain an extended system and lexicographic optimization to yield unique exchange fluxes, is presented. DFBAlab is able to simulate complex dynamic cultures with multiple species rapidly and reliably, including differential-algebraic equation (DAE) systems. In addition, DFBAlab's running time scales linearly with the number of species models. Three examples are presented where the performance of COBRA, DyMMM and DFBAlab are compared. CONCLUSIONS: Lexicographic optimization is used to determine unique exchange fluxes which are necessary for a well-defined dynamic system. DFBAlab does not fail during numerical integration due to infeasible LPs. The extended system obtained through the LP feasibility problem in DFBAlab provides a penalty function that can be used in optimization algorithms.


Assuntos
Algoritmos , Bactérias/metabolismo , Reatores Biológicos , Biotecnologia/métodos , Redes e Vias Metabólicas , Modelos Teóricos , Biologia de Sistemas/métodos , Bactérias/crescimento & desenvolvimento , Simulação por Computador
19.
Stem Cells ; 31(8): 1669-82, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23666637

RESUMO

Mesenchymal stem cells (MSCs) transplanted into injured myocardium promote repair through paracrine mechanisms. We have previously shown that MSCs over-expressing AKT1 (Akt-MSCs) exhibit enhanced properties for cardiac repair. In this study, we investigated the relevance of Abi3bp toward MSC biology. Abi3bp formed extracellular deposits with expression controlled by Akt1 and ubiquitin-mediated degradation. Abi3bp knockdown/knockout stabilized focal adhesions and promoted stress-fiber formation. Furthermore, MSCs from Abi3bp knockout mice displayed severe deficiencies in osteogenic and adipogenic differentiation. Knockout or stable knockdown of Abi3bp increased MSC and Akt-MSC proliferation, promoting S-phase entry via cyclin-d1, ERK1/2, and Src. Upon Abi3bp binding to integrin-ß1 Src associated with paxillin which inhibited proliferation. In vivo, Abi3bp knockout increased MSC number and proliferation in bone marrow, lung, and liver. In summary, we have identified a novel extracellular matrix protein necessary for the switch from proliferation to differentiation in MSCs.


Assuntos
Proteínas de Transporte/fisiologia , Comunicação Celular/fisiologia , Células-Tronco Mesenquimais/fisiologia , Animais , Comunicação Autócrina , Proteínas de Transporte/metabolismo , Diferenciação Celular/fisiologia , Processos de Crescimento Celular/fisiologia , Movimento Celular/fisiologia , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Comunicação Parácrina , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transfecção , Ubiquitina/metabolismo
20.
J Hum Evol ; 75: 1-15, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25063566

RESUMO

We present a bioanthropological study of dental remains recovered from El Salt Middle Palaeolithic site (Alcoy, Alicante, Spain). The dental remains were found in a sedimentary layer representing a calm depositional environment within a freshwater spring system. The corresponding archaeological context comprises a Middle Palaeolithic faunal and lithic assemblage that represents the last documented evidence of human occupation at the site, dating to between 47.2 ± 4.4 and 45.2 ± 3.4 ka (thousands of years ago). This evidence is overlain by an archaeologically sterile deposit dated to 44.7 ± 3.2 ka. Results show that the teeth belong to a single juvenile or young adult individual with morphological and metric features falling within the Neanderthal range of variability, although the considered traits are not taxonomically highly discriminant. The reported fossils are representative of the latest Middle Palaeolithic groups in the region and may be considered in the ongoing debate on the disappearance of Neanderthals and the end of the Middle Palaeolithic.


Assuntos
Homem de Neandertal/anatomia & histologia , Dente/anatomia & histologia , Adulto , Animais , Cavidade Pulpar/anormalidades , Fósseis , Humanos , Paleodontologia , Espanha , Dente/patologia , Anormalidades Dentárias , Adulto Jovem
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