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1.
Artigo em Inglês | MEDLINE | ID: mdl-38606934

RESUMO

BACKGROUND: Whether testosterone replacement therapy (TRT) conveys additional cardiometabolic benefit to an intensive lifestyle therapy (LT) in older men with obesity and hypogonadism remains unclear. OBJECTIVE: To determine whether TRT augments the effect of LT on metabolic outcomes in older men with obesity and hypogonadism. DESIGN: Secondary analysis of a randomized, double-blind, placebo-controlled trial. SETTING: Veterans Affairs Medical Center. PARTICIPANTS: 83 older (age ≥ 65 years) men with obesity (BMI ≥ 30 kg/m2) and persistently low AM testosterone (< 10.4 nmol/L) associated with frailty. INTERVENTIONS: LT (weight management and exercise training) plus either testosterone (LT+TRT) or placebo (LT+Pbo) for six months. OUTCOME MEASURES: Primary outcome was change in glycated hemoglobin (HbA1c). Secondary outcomes included changes in other glucometabolic and lipid profile components, liver enzymes, inflammatory markers, adipokines; subcutaneous, visceral, intramuscular, and hepatic fat; blood pressure, and metabolic syndrome score. RESULTS: HbA1c decreased similarly in LT+TRT and LT+Pbo groups (-0.5% vs. -0.6%, respectively; p= 0.35). While TRT showed no synergistic effect with LT on ameliorating secondary outcomes, it eliminated the augmentative effect of LT on high-density lipoprotein cholesterol concentration (5.4 ± 1.0 mg/dL in LT+Pbo group vs. 0.2 ± 1.1 mg/dL in LT+TRT group, p= 0.01) and adiponectin levels (-408 ± 489 ng/mL in TRT+LT group vs 1832 ± 468 ng/mL in LT+Pbo group, p= 0.02). CONCLUSION: In older men with obesity and hypogonadism, adding TRT for six months to LT does not result in further improved cardiometabolic profiles, and could potentially blunt some of the metabolic benefits induced by LT.

2.
Cell Host Microbe ; 32(4): 506-526.e9, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38479397

RESUMO

To understand the dynamic interplay between the human microbiome and host during health and disease, we analyzed the microbial composition, temporal dynamics, and associations with host multi-omics, immune, and clinical markers of microbiomes from four body sites in 86 participants over 6 years. We found that microbiome stability and individuality are body-site specific and heavily influenced by the host. The stool and oral microbiome are more stable than the skin and nasal microbiomes, possibly due to their interaction with the host and environment. We identify individual-specific and commonly shared bacterial taxa, with individualized taxa showing greater stability. Interestingly, microbiome dynamics correlate across body sites, suggesting systemic dynamics influenced by host-microbial-environment interactions. Notably, insulin-resistant individuals show altered microbial stability and associations among microbiome, molecular markers, and clinical features, suggesting their disrupted interaction in metabolic disease. Our study offers comprehensive views of multi-site microbial dynamics and their relationship with host health and disease.


Assuntos
Estabilidade Central , Microbiota , Humanos , Pele/microbiologia , Interações entre Hospedeiro e Microrganismos , Biomarcadores
3.
bioRxiv ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38352363

RESUMO

To understand dynamic interplay between the human microbiome and host during health and disease, we analyzed the microbial composition, temporal dynamics, and associations with host multi-omics, immune and clinical markers of microbiomes from four body sites in 86 participants over six years. We found that microbiome stability and individuality are body-site-specific and heavily influenced by the host. The stool and oral microbiome were more stable than the skin and nasal microbiomes, possibly due to their interaction with the host and environment. Also, we identified individual-specific and commonly shared bacterial taxa, with individualized taxa showing greater stability. Interestingly, microbiome dynamics correlated across body sites, suggesting systemic coordination influenced by host-microbial-environment interactions. Notably, insulin-resistant individuals showed altered microbial stability and associations between microbiome, molecular markers, and clinical features, suggesting their disrupted interaction in metabolic disease. Our study offers comprehensive views of multi-site microbial dynamics and their relationship with host health and disease. Study Highlights: The stability of the human microbiome varies among individuals and body sites.Highly individualized microbial genera are more stable over time.At each of the four body sites, systematic interactions between the environment, the host and bacteria can be detected.Individuals with insulin resistance have lower microbiome stability, a more diversified skin microbiome, and significantly altered host-microbiome interactions.

4.
Front Endocrinol (Lausanne) ; 14: 1279321, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38027147

RESUMO

Background: The expanding population of older adults with obesity is a public health challenge, in part, because of the increased risk of fractures despite normal or high bone mineral density. Potential factors predisposing to fractures in this group include sarcopenia associated with obesity and impaired bone quality. We aimed to determine the contribution of sarcopenic obesity (SO) indices to bone strength as assessed by microfinite element analysis (µFEA) of high-resolution peripheral quantitative computed tomography (HR-pQCT). Methods: One-hundred eighty-nine older (age ≥ 65 years) adults with obesity (BMI ≥ 30 kg/m2) participated in lifestyle intervention trials at our medical center. All underwent baseline measurements of bone strength (failure load and stiffness) using µFEA from HR-pQCT of the distal radius and tibia. In addition, SO indices [appendicular lean mass/weight (ALM/W) and percent body fat (FM%)] by dual-energy X-ray absorptiometry and handgrip strength (HGS) by dynamometry were assessed. SO was diagnosed and staged based on the 2022 ESPEN and EASO expert consensus statement. Results: Both ALM/W and HGS were positively correlated explaining 28% to 36% of the variance in failure load and stiffness at the distal radius and tibia (all p < 0.001). In contrast, FM% was negatively correlated explaining 22% to 31% of the variance in failure load and stiffness at the distal radius and tibia (all p < 0.001). The associations of SO indices with failure load and stiffness remained significant after controlling for age, sex, race/ethnicity, diabetes, and 25-OH vitamin D (ALM/W: R 2 = 0.301 to 0.448, HGS: R 2 = 0.346 to 0.472, FM%: R 2 = 0.299 to 0.432) (p < 0.001 to 0.011). SO was diagnosed in 75/189 (40%) participants with 66/75 (88%) having functional or metabolic complications (stage II). Participants with SO had lower failure load and stiffness at the distal radius than participants with no SO (both p < 0.05). Conclusion: These findings demonstrate that lower muscle mass and strength and higher fat mass may impair bone quality. Therefore, interventions that focus on preserving muscle mass and strength while reducing fat mass may be important to decrease fracture risk when older adults with obesity undertake lifestyle intervention therapy.


Assuntos
Fraturas Ósseas , Sarcopenia , Humanos , Idoso , Sarcopenia/etiologia , Densidade Óssea , Análise de Elementos Finitos , Força da Mão , Obesidade/complicações
5.
Diabetes Care ; 45(9): 1943-1952, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35880801

RESUMO

OBJECTIVE: Lifestyle intervention is recommended as first-line treatment of diabetes at all ages; however, little is known about the efficacy of lifestyle intervention in older adults with diabetes. We aimed to determine whether lifestyle intervention would improve glycemic control and age-relevant outcomes in older adults with diabetes and comorbidities. RESEARCH DESIGN AND METHODS: A total of 100 older adults with diabetes were randomly assigned to 1-year intensive lifestyle intervention (ILI) (diet and exercise at a facility transitioned into community-fitness centers and homes) or healthy lifestyle (HL) group. The primary outcome was change in HbA1c. Secondary outcomes included glucoregulation, body composition, physical function, and quality of life. Changes between groups were analyzed with mixed-model repeated-measures ANCOVA following the intention-to-treat principle. RESULTS: HbA1c improved more in the ILI than the HL group (mean ± SE -0.8 ± 0.1 vs. 0.1 ± 0.1%), associated with improved insulin sensitivity (1.2 ± 0.2 vs. -0.4 ± 0.2) and disposition (26.0 ± 8.9 vs. -13.0 ± 8.4 109 min-1) indices (between-group P < 0.001 to 0.04). Body weight and visceral fat decreased more in the ILI than HL group (-8.4 ± 0.6 vs. -0.3 ± 0.6 kg, P < 0.001, and -261 ± 29 vs. -30 ± 27 cm3, P < 0.001, respectively). Physical Performance Test score increased more in the ILI than HL group (2.9 ± 0.6 vs. -0.1 ± 0.4, P < 0.001) as did VO2peak (2.2 ± 0.3 vs. -1.2 ± 0.2 mL/kg/min, P < 0.001). Strength, gait, and 36-Item Short Form Survey (SF-36) Physical Component Summary score also improved more in the ILI group (all P < 0.001). Total insulin dose decreased in the ILI group by 19.8 ± 4.4 units/day. Adverse events included increased episodes of mild hypoglycemia in the ILI group. CONCLUSIONS: A lifestyle intervention strategy is highly successful in improving metabolic and functional health of older adults with diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Redução de Peso , Idoso , Diabetes Mellitus Tipo 2/complicações , Hemoglobinas Glicadas , Humanos , Estilo de Vida , Qualidade de Vida , Redução de Peso/fisiologia
6.
Nat Med ; 28(1): 175-184, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34845389

RESUMO

Early detection of infectious diseases is crucial for reducing transmission and facilitating early intervention. In this study, we built a real-time smartwatch-based alerting system that detects aberrant physiological and activity signals (heart rates and steps) associated with the onset of early infection and implemented this system in a prospective study. In a cohort of 3,318 participants, of whom 84 were infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), this system generated alerts for pre-symptomatic and asymptomatic SARS-CoV-2 infection in 67 (80%) of the infected individuals. Pre-symptomatic signals were observed at a median of 3 days before symptom onset. Examination of detailed survey responses provided by the participants revealed that other respiratory infections as well as events not associated with infection, such as stress, alcohol consumption and travel, could also trigger alerts, albeit at a much lower mean frequency (1.15 alert days per person compared to 3.42 alert days per person for coronavirus disease 2019 cases). Thus, analysis of smartwatch signals by an online detection algorithm provides advance warning of SARS-CoV-2 infection in a high percentage of cases. This study shows that a real-time alerting system can be used for early detection of infection and other stressors and employed on an open-source platform that is scalable to millions of users.


Assuntos
COVID-19/diagnóstico , Portador Sadio/diagnóstico , Exercício Físico , Frequência Cardíaca/fisiologia , Dispositivos Eletrônicos Vestíveis , Acelerometria , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/fisiopatologia , Portador Sadio/fisiopatologia , Diagnóstico Precoce , Feminino , Monitores de Aptidão Física , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Sono , Adulto Jovem
7.
Nat Commun ; 12(1): 5757, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599181

RESUMO

The large amount of biomedical data derived from wearable sensors, electronic health records, and molecular profiling (e.g., genomics data) is rapidly transforming our healthcare systems. The increasing scale and scope of biomedical data not only is generating enormous opportunities for improving health outcomes but also raises new challenges ranging from data acquisition and storage to data analysis and utilization. To meet these challenges, we developed the Personal Health Dashboard (PHD), which utilizes state-of-the-art security and scalability technologies to provide an end-to-end solution for big biomedical data analytics. The PHD platform is an open-source software framework that can be easily configured and deployed to any big data health project to store, organize, and process complex biomedical data sets, support real-time data analysis at both the individual level and the cohort level, and ensure participant privacy at every step. In addition to presenting the system, we illustrate the use of the PHD framework for large-scale applications in emerging multi-omics disease studies, such as collecting and visualization of diverse data types (wearable, clinical, omics) at a personal level, investigation of insulin resistance, and an infrastructure for the detection of presymptomatic COVID-19.


Assuntos
Ciência de Dados/métodos , Sistemas Computadorizados de Registros Médicos , Big Data , Segurança Computacional , Análise de Dados , Interoperabilidade da Informação em Saúde , Humanos , Armazenamento e Recuperação da Informação , Software
8.
Am J Clin Nutr ; 114(5): 1590-1599, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34375393

RESUMO

BACKGROUND: Both obesity and hypogonadism are common in older men which could additively exacerbate age-related declines in cognitive function. However, little is known about the effects of lifestyle intervention plus testosterone replacement therapy in this population. OBJECTIVES: In this secondary analysis of the LITROS (Lifestyle Intervention and Testosterone Replacement in Obese Seniors) trial, we examined whether testosterone replacement therapy would improve cognitive function when added to intensive lifestyle intervention in older men with obesity and hypogonadism. METHODS: Eighty-three older, obese hypogonadal men with frailty were randomly assigned to lifestyle therapy (weight management and exercise training) plus testosterone (LT + Test) or lifestyle therapy plus placebo (LT + Pbo) for 6 mo. For this report, the primary outcome was change in the global cognition composite z score. Secondary outcomes included changes in z score subcomponents: attention/information processing, memory, executive function, and language. Changes between groups were analyzed using mixed-model repeated-measures ANCOVAs following the intention-to-treat principle. RESULTS: Global cognition z score increased more in the LT + Test than in the LT + Pbo group (mean change: 0.49 compared with 0.21; between-group difference: -0.28; 95% CI: -0.45, -0.11; Cohen's d = 0.74). Moreover, attention/information z score and memory z score increased more in the LT + Test than in the LT + Pbo group (mean change: 0.55 compared with 0.23; between-group difference: -0.32; 95% CI: -0.55, -0.09; Cohen's d = 0.49 and mean change: 0.90 compared with 0.37; between-group difference: -0.53; 95% CI: -0.93, -0.13; Cohen's d = 1.43, respectively). Multiple regression analyses showed that changes in peak oxygen consumption, strength, total testosterone, and luteinizing hormone were independent predictors of the improvement in global cognition (R2 = 0.38; P < 0.001). CONCLUSIONS: These findings suggest that in the high-risk population of older men with obesity and hypogonadism, testosterone replacement may improve cognitive function with lifestyle behaviors controlled via lifestyle intervention therapy.This trial was registered at clinicaltrials.gov as NCT02367105.


Assuntos
Cognição/efeitos dos fármacos , Terapia de Reposição Hormonal , Hipogonadismo/tratamento farmacológico , Estilo de Vida , Obesidade/tratamento farmacológico , Testosterona/uso terapêutico , Idoso , Método Duplo-Cego , Humanos , Hipogonadismo/psicologia , Masculino , Obesidade/psicologia , Consumo de Oxigênio
9.
medRxiv ; 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34189532

RESUMO

Early detection of infectious disease is crucial for reducing transmission and facilitating early intervention. We built a real-time smartwatch-based alerting system for the detection of aberrant physiological and activity signals (e.g. resting heart rate, steps) associated with early infection onset at the individual level. Upon applying this system to a cohort of 3,246 participants, we found that alerts were generated for pre-symptomatic and asymptomatic COVID-19 infections in 78% of cases, and pre-symptomatic signals were observed a median of three days prior to symptom onset. Furthermore, by examining over 100,000 survey annotations, we found that other respiratory infections as well as events not associated with COVID-19 (e.g. stress, alcohol consumption, travel) could trigger alerts, albeit at a lower mean period (1.9 days) than those observed in the COVID-19 cases (4.3 days). Thus this system has potential both for advanced warning of COVID-19 as well as a general system for measuring health via detection of physiological shifts from personal baselines. The system is open-source and scalable to millions of users, offering a personal health monitoring system that can operate in real time on a global scale.

10.
J Clin Endocrinol Metab ; 106(3): e1096-e1110, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33351921

RESUMO

BACKGROUND: Obesity and hypogonadism additively contribute to frailty in older men; however, appropriate treatment remains controversial. OBJECTIVE: Determine whether testosterone replacement augments the effect of lifestyle therapy on physical function in older men with obesity and hypogonadism. DESIGN: Randomized, double-blind, placebo-controlled trial. SETTING: VA Medical Center. PARTICIPANTS: 83 older (age ≥65 years) men with obesity (body mass index ≥30 kg/m2) and persistently low am testosterone (<10.4 nmol/L) associated with frailty. INTERVENTIONS: Participants were randomized to lifestyle therapy (weight management and exercise training) plus either testosterone (LT+Test) or placebo (LT+Pbo) for 6 months. OUTCOME MEASURES: Primary outcome was change in Physical Performance Test (PPT) score. Secondary outcomes included other frailty measures, body composition, hip bone mineral density (BMD), physical functions, hematocrit, prostate specific antigen (PSA), and sex hormones. RESULTS: PPT score increased similarly in LT+Test and LT+Pbo group (17% vs. 16%; P = 0.58). VO2peak increased more in LT+Test than LT+Pbo (23% vs. 16%; P = 0.03). Despite similar -9% weight loss, lean body mass and thigh muscle volume decreased less in LT+Test than LT+Pbo (-2% vs. -3%; P = 0.01 and -2% vs -4%; P = 0.04). Hip BMD was preserved in LT+Test compared with LT+Pbo (0.5% vs -1.1%; P = 0.003). Strength increased similarly in LT+Test and LT+Pbo (23% vs 22%; P = 0.94). Hematocrit but not PSA increased more in LT+Test than LT+Pbo (5% vs 1%; P < 0.001). Testosterone levels increased more in LT+Test than LT+Pbo (167% vs 27%; P < 0.001). CONCLUSION: In older, obese hypogonadal men, adding testosterone for 6 months to lifestyle therapy does not further improve overall physical function. However, our findings suggest that testosterone may attenuate the weight loss-induced reduction in muscle mass and hip BMD and may further improve aerobic capacity.


Assuntos
Terapia Comportamental , Hipogonadismo/terapia , Obesidade/terapia , Testosterona/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/efeitos dos fármacos , Envelhecimento/fisiologia , Terapia Comportamental/métodos , Densidade Óssea/efeitos dos fármacos , Terapia Combinada , Método Duplo-Cego , Exercício Físico/fisiologia , Terapia por Exercício , Idoso Fragilizado , Terapia de Reposição Hormonal , Humanos , Hipogonadismo/complicações , Hipogonadismo/metabolismo , Hipogonadismo/fisiopatologia , Estilo de Vida , Masculino , Obesidade/complicações , Obesidade/metabolismo , Obesidade/fisiopatologia , Estados Unidos , Redução de Peso/efeitos dos fármacos , Programas de Redução de Peso
11.
Nat Biomed Eng ; 4(12): 1208-1220, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33208926

RESUMO

Consumer wearable devices that continuously measure vital signs have been used to monitor the onset of infectious disease. Here, we show that data from consumer smartwatches can be used for the pre-symptomatic detection of coronavirus disease 2019 (COVID-19). We analysed physiological and activity data from 32 individuals infected with COVID-19, identified from a cohort of nearly 5,300 participants, and found that 26 of them (81%) had alterations in their heart rate, number of daily steps or time asleep. Of the 25 cases of COVID-19 with detected physiological alterations for which we had symptom information, 22 were detected before (or at) symptom onset, with four cases detected at least nine days earlier. Using retrospective smartwatch data, we show that 63% of the COVID-19 cases could have been detected before symptom onset in real time via a two-tiered warning system based on the occurrence of extreme elevations in resting heart rate relative to the individual baseline. Our findings suggest that activity tracking and health monitoring via consumer wearable devices may be used for the large-scale, real-time detection of respiratory infections, often pre-symptomatically.


Assuntos
COVID-19/diagnóstico , COVID-19/prevenção & controle , Pandemias/prevenção & controle , Adulto , Doenças Assintomáticas , Feminino , Humanos , Masculino , Monitorização Fisiológica/métodos , Estudos Retrospectivos , SARS-CoV-2/patogenicidade , Dispositivos Eletrônicos Vestíveis
12.
Clin Chem Lab Med ; 42(10): 1186-202, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15552279

RESUMO

The E170 module was evaluated at 13 sites in an international multicentre study. The objective of the study was to assess the analytical performance of 49 analytes, and to collect feedback on the system's reliability and practicability. The typical, within-run coefficients of variation (CVs) for most of the quantitative assays ranged between 1 and 2% while a range of 2-4% was achieved with the infectious disease methods. Total precision CVs were found to be within the manufacturer's expected performance ranges, demonstrating good concordance of the system's measuring channels and a high reproducibility during the 2-4-week trial period. The functional sensitivity of 11 selected assays met the clinical requirements (e.g., thyreotroponin (TSH) 0.008 mU/l, troponin T 0.02 microg/l, total prostate-specific antigen (PSA) 0.03 microg/l). The E170 showed no drift during an 8-hour period and no relevant reagent carryover. Accuracy was confirmed by ring trial experiments and method comparisons vs. Elecsys 2010. The reliability and practicability of the system's hardware and software met with, or even exceeded, the evaluator's requirements. Workflow studies showed that E170 can cover the combined workload of various routine analysers in a variety of laboratory environment. Throughput and sample processing time requirements were achieved while personnel 'hands-on-time' could be reduced.


Assuntos
Química Clínica/métodos , Reprodutibilidade dos Testes , Calibragem , Ferritinas/sangue , Humanos , Masculino , Antígeno Prostático Específico/sangue , Kit de Reagentes para Diagnóstico/classificação , Kit de Reagentes para Diagnóstico/normas , Sensibilidade e Especificidade , Software , Tireotropina/sangue , Tempo , Troponina/sangue
13.
Free Radic Res ; 37(3): 331-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12688429

RESUMO

We investigated the effect of 3-aminobenzamide (3-AB), an inhibitor of the nuclear enzyme poly(ADP-ribose) polymerase (PARP), against early ischemia/reperfusion (IR) injury in heart transplantation. In our experimental model, rat heart subjected to heterotopic transplantation, low temperature global ischemia (2 h) was followed by an in vivo reperfusion (60 min). In these conditions, and in the absence of 3-AB treatment, clear signs of oxidative stress, such as lipid peroxidation, increase in protein carbonyls and DNA strand breaks, were evident; PARP was markedly activated in concomitance with a significant NAD+ and ATP depletion. The results of microscopic observations (nuclear clearings, plasma membrane discontinuity), and the observed rise in the serum levels of heart damage markers, suggested the development of necrotic processes while, conversely, no typical sign of apoptosis was evident. Compared to the effects observed in untreated IR heart, the administration of 3-AB (10 mg/kg to the donor and to the recipient animal), but not that of its inactive analogue 3-aminobenzoic acid, significantly modified the above parameters: the levels of oxidative stress markers were significantly reduced; PARP activation was markedly inhibited and this matched a significant rise in NAD+ and ATP levels. PARP inhibition also caused a reduced release of the cardiospecific damage markers and attenuated morphological cardiomyocyte alterations, save that, in this condition, we noted the appearance of typical apoptotic markers: activation of caspase-3, oligonucleosomal DNA fragmentation, ISEL positive nuclei. Possible mechanisms for these effects are discussed, in any case the present results indicate that PARP inhibition has an overall beneficial effect against myocardial reperfusion injury, mainly due to prevention of energy depletion. In this context, the signs of apoptosis observed under 3-AB treatment might be ascribed to the maintenance of sufficient intracellular energy levels. These latter allow irreversible damages triggered during the ischemic phase to proceed towards apoptosis instead of towards necrosis, as it appears to happen when the energetic pools are depleted by high PARP activity.


Assuntos
Benzamidas/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Transplante de Coração/métodos , Inibidores de Poli(ADP-Ribose) Polimerases , Traumatismo por Reperfusão/prevenção & controle , Trifosfato de Adenosina/metabolismo , Animais , Apoptose , Western Blotting , Caspase 3 , Caspases/metabolismo , Núcleo Celular/metabolismo , Creatina Quinase/metabolismo , Dano ao DNA , Fragmentação do DNA , Ativação Enzimática , Ensaio de Imunoadsorção Enzimática , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos , Miocárdio/metabolismo , NAD/metabolismo , Ratos , Temperatura , Troponina I/metabolismo
14.
Biochem Biophys Res Commun ; 301(4): 948-51, 2003 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-12589804

RESUMO

We previously reported that acylphosphatase, a cytosolic enzyme present in skeletal and heart muscle, actively hydrolyzes the phosphoenzyme (EP) of cardiac sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA2a), inducing an increased activity of this pump. We hypothesized that acylphosphatase-induced stimulation of SERCA2a, in addition to enhanced EP hydrolysis, may be due to a displacement of phospholamban (PLN), removing its inhibitory effect. To verify this hypothesis co-immunoprecipitation experiments were performed by adding recombinant muscle acylphosphatase to solubilized heart SR vesicles, used as a source of SERCA2a and PLN. With anti-acylphosphatase antibodies only SERCA2a was co-immunoprecipitated in an amount which increased in parallel to the concentrations of our enzyme. Conversely, using anti-SERCA2a antibody, both PLN and acylphosphatase were co-immunoprecipitated with SERCA2a, and the PLN amount in the precipitate decreased with increasing acylphosphatase concentrations. SERCA2a and PLN were co-immunoprecipitated by anti-phospholamban antibodies, but while the amount of precipitated phospholamban increased in the presence of acylphosphatase, the level of SERCA2a decreased. These preliminary results strengthen the supposed displacement of phospholamban by acylphosphatase.


Assuntos
Hidrolases Anidrido Ácido/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Animais , Anticorpos Monoclonais , Ligação Competitiva , Técnicas In Vitro , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Testes de Precipitina , Coelhos , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático , Acilfosfatase
15.
IUBMB Life ; 53(3): 175-81, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12102174

RESUMO

The response of C2C12 myoblasts to 1 nM 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], two vitamin D analogues (KH 1060 and EB 1089, which are 20-epi-22-oxa and 22,24-diene-analogues, respectively), 100 nM retinoids (9-cis retinoic acid, all-trans retinoic acid) and to combination treatments, after 72 h incubation, was studied. The incubation with 1,25(OH)2D3 was ineffective on either cell proliferation or [3H]thymidine incorporation (expressed as DPM per cell) or protein content per cell. On the contrary, all the other treatments inhibited cell proliferation, this inhibition being synergistic when the vitamin D derivatives were combined with 9-cis or all-trans retinoic acid, and increased [3H]thymidine incorporation and protein content per cell. The levels of the VDR protein remarkably increased in comparison with control cells, except for the incubation with 9-cis retinoic acid. This increase was particularly accentuated in C2C12 cells treated with KH 1060 and 9-cis retinoic acid in combination. These results, taken together, suggest a role for vitamin D derivatives and retinoids on C2C12 cells.


Assuntos
Calcitriol/análogos & derivados , Músculo Esquelético/fisiologia , Retinoides/farmacologia , Vitamina D/análogos & derivados , Vitamina D/farmacologia , Alitretinoína , Animais , Transporte Biológico , Calcitriol/farmacologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Sinergismo Farmacológico , Cinética , Camundongos , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Relação Estrutura-Atividade , Tretinoína/farmacologia , Vitamina D/farmacocinética
16.
Am J Gastroenterol ; 97(3): 679-89, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11922564

RESUMO

OBJECTIVE: 1,25-Dihydroxyvitamin D3 [1,25(OH)2D3], the hormonal active form of vitamin D3, could represent a potentially therapeutic agent in autoimmune diseases. Cyclosporin A (CsA) shows immunoregulatory properties, which, in many respects, seem to be similar to those of 1,25(OH)2D3. Our aim was to investigate the possible synergistic effect exerted by CsA in combination with 1,25(OH)2D3 or its nonhypercalcemic analogues, EB 1089 and KH 1060, on the proliferative response of T lymphocytes obtained from active ulcerative colitis patients. METHODS: The T lymphocyte-enriched population was treated with phytohemagglutinin and CsA (doses from 1 ng to 1000 ng/ml) alone or in association with 1,25(OH)2D3 or EB 1089 or KH 1060 (0.1, 1, 10 nM final concentration). Cell proliferation was determined by [3H]thymidine incorporation and analyzed on day 5 of culture. RESULTS: After incubation with CsA, T lymphocyte proliferation was significantly inhibited in comparison with the vehicle-treated cultures. However, T lymphocytes from ulcerative colitis patients were significantly more sensitive to CsA than those from healthy controls. The inhibition in T lymphocyte proliferation, after treatment of the cultures with CsA associated with either 1,25(OH)2D3 or EB 1089 or KH 1060, was synergistic at well-defined concentrations. CONCLUSIONS: Taking into account the lowest CsA dose (1 ng/ml), the highest synergistic inhibition in the proliferation of T lymphocytes prepared from ulcerative colitis patients was found combining CsA and 10 nM of 1,25(OH)2D3 or 10 nM of EB 1089 or KH 1060 at the three concentrations. The results obtained, associating the lowest CsA dose and the lowest KH 1060 concentration, may suggest an alternative therapeutic approach in these patients, reducing the dose, and consequently the toxicity, of CsA.


Assuntos
Calcitriol/análogos & derivados , Calcitriol/farmacologia , Fenômenos Fisiológicos Celulares/efeitos dos fármacos , Colite Ulcerativa/fisiopatologia , Ciclosporina/farmacologia , Sinergismo Farmacológico , Imunossupressores/farmacologia , Linfócitos T/efeitos dos fármacos , Vitamina D/análogos & derivados , Vitamina D/farmacologia , Adulto , Calcitriol/administração & dosagem , Calcitriol/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Ciclosporina/administração & dosagem , Ciclosporina/uso terapêutico , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Vitamina D/uso terapêutico
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