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1.
JAMA ; 314(6): 570-81, 2015 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-26262795

RESUMO

IMPORTANCE: Testosterone use in older men is increasing, but its long-term effects on progression of atherosclerosis are unknown. OBJECTIVE: To determine the effect of testosterone administration on subclinical atherosclerosis progression in older men with low or low-normal testosterone levels. DESIGN, SETTING, AND PARTICIPANTS: Testosterone's Effects on Atherosclerosis Progression in Aging Men (TEAAM) was a placebo-controlled, double-blind, parallel-group randomized trial involving 308 men 60 years or older with low or low-normal testosterone levels (100-400 ng/dL; free testosterone <50 pg/mL), recruited at 3 US centers. Recruitment took place between September 2004 and February 2009; the last participant completed the study in May 2012. INTERVENTIONS: One hundred fifty-six participants were randomized to receive 7.5 g of 1% testosterone and 152 were randomized to receive placebo gel packets daily for 3 years. The dose was adjusted to achieve testosterone levels between 500 and 900 ng/dL. MAIN OUTCOMES AND MEASURES: Coprimary outcomes included common carotid artery intima-media thickness and coronary artery calcium; secondary outcomes included sexual function and health-related quality of life. RESULTS: Baseline characteristics were similar between groups: patients were a mean age of 67.6 years; 42% had hypertension; 15%, diabetes; 15%, cardiovascular disease; and 27%, obesity. The rate of change in intima-media thickness was 0.010 mm/year in the placebo group and 0.012 mm/year in the testosterone group (mean difference adjusted for age and trial site, 0.0002 mm/year; 95% CI, -0.003 to 0.003, P = .89). The rate of change in the coronary artery calcium score was 41.4 Agatston units/year in the placebo group and 31.4 Agatston units/year in the testosterone group (adjusted mean difference, -10.8 Agatston units/year; 95% CI, -45.7 to 24.2; P = .54). Changes in intima-media thickness or calcium scores were not associated with change in testosterone levels among individuals assigned to receive testosterone. Sexual desire, erectile function, overall sexual function scores, partner intimacy, and health-related quality of life did not differ significantly between groups. Hematocrit and prostate-specific antigen levels increased more in testosterone group. CONCLUSIONS AND RELEVANCE: Among older men with low or low-normal testosterone levels, testosterone administration for 3 years vs placebo did not result in a significant difference in the rates of change in either common carotid artery intima-media thickness or coronary artery calcium nor did it improve overall sexual function or health-related quality of life. Because this trial was only powered to evaluate atherosclerosis progression, these findings should not be interpreted as establishing cardiovascular safety of testosterone use in older men. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00287586.


Assuntos
Aterosclerose/induzido quimicamente , Espessura Intima-Media Carotídea , Testosterona/efeitos adversos , Idoso , Cálcio/análise , Vasos Coronários/química , Progressão da Doença , Método Duplo-Cego , Nível de Saúde , Humanos , Hipertensão , Masculino , Pessoa de Meia-Idade , Obesidade , Qualidade de Vida , Disfunções Sexuais Fisiológicas/complicações , Disfunções Sexuais Fisiológicas/etiologia , Testosterona/sangue , Testosterona/deficiência , Testosterona/uso terapêutico , Resultado do Tratamento
2.
Oxid Med Cell Longev ; 2022: 6110226, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571254

RESUMO

Background: Aging is a major risk factor for a range of chronic diseases. Oxidative stress theory of aging has been previously proposed as one of the mechanisms responsible for the age-related decline in organ/tissue function and the development of age-related diseases. Urine contains rich biological information on the health status of every major organ system and can be an important noninvasive source for biomarkers of systemic oxidative stress in aging. Aims: The objective of this cross-sectional study was to validate a novel panel of urinary oxidative stress biomarkers. Methods: Nucleic acid oxidation adducts and oxidative damage markers of lipids and proteins were assessed in urine samples from nondiabetic and currently nonsmoking subjects (n = 198) across different ages (20 to 89 years old). Urinary parameters and chronological age were correlated then the biological age of enrolled individuals was determined from the urinary oxidative stress markers using the algorithm of Klemera and Doubal. Results: Our findings showed that 8-oxo-7,8-deoxyguanosine (8-oxoG), 8-oxo-7,8-dihydroguanosine (8-OHdG), and dityrosine (DTyr) positively correlated with chronological age, while the level of an F2-isoprostane (iPF2 α-VI) correlated negatively with age. We found that 8-oxoG, DTyr, and iPF2 α-VI were significantly higher among accelerated agers compared to nonaccelerated agers and that a decision tree model could successfully identify accelerated agers with an accuracy of >92%. Discussion. Our results indicate that 8-oxoG and iPF2 α-VI levels in the urine reveal biological aging. Conclusion: Assessing urinary biomarkers of oxidative stress may be an important approach for the evaluation of biological age by identifying individuals at accelerated risk for the development of age-related diseases.


Assuntos
Envelhecimento , Estresse Oxidativo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/urina , Estudos Transversais , Desoxiguanosina/urina , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
3.
J Gerontol A Biol Sci Med Sci ; 75(6): 1167-1175, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-31282538

RESUMO

BACKGROUND: Standardization of performance-based physical function measures that are reliable and responsive to intervention is necessary for efficacy trials of function promoting anabolic therapies (FPTs). Herein, we describe a standardized method of measuring stair climbing power (SCP) and evaluate its ability to assess improvements in physical function in response to an FPT (testosterone) compared to gait speed. METHODS: We used a 12-step SCP test with and without carrying a load (loaded, LSCP or unloaded, USCP) in two testosterone trials in older men. SCP was determined from mass, total step-rise, and time of ascent measured with an electronic timing system. Associations between SCP and leg press performance (strength and power), testosterone levels, and gait speed were assessed. Test-retest reliability was evaluated using interclass correlation and Bland-Altman analyses. RESULTS: Baseline SCP was negatively associated with age and positively with leg strength and power and gait speed. Both tests of SCP were safe and showed excellent reliability (intra-class correlation 0.91-0.97 in both cohorts). Changes in testosterone concentrations were associated with changes in USCP and LSCP, but not gait speed in mobility-limited men. Changes in leg press performance were associated with SCP in both trials. CONCLUSIONS: Both USCP and LSCP are safe and have high test-retest reliability. Compared to gait speed, SCP is associated more robustly with leg press performance and is sensitive to testosterone therapy. The LSCP might be a more responsive outcome than gait speed to evaluate the efficacy of FPT in randomized trials.


Assuntos
Teste de Esforço , Subida de Escada/fisiologia , Administração Cutânea , Idoso , Teste de Esforço/métodos , Teste de Esforço/normas , Géis , Avaliação Geriátrica/métodos , Humanos , Masculino , Aptidão Física , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Reprodutibilidade dos Testes , Subida de Escada/efeitos dos fármacos , Testosterona/administração & dosagem , Testosterona/uso terapêutico , Resultado do Tratamento
4.
Drugs Aging ; 36(11): 981-989, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31595418

RESUMO

The number of older adults over 65 years of age is expected to increase to almost 100 million in the US by 2050, more than double the current figure of 46 million. Advanced age is associated with increased frailty among older Americans and often leads to increased disability, hospitalization, institutionalization, and, eventually, mortality. In search of means to improve age-related risks for adverse health outcomes, the question of restoring diminishing sex hormones has gathered much interest and has led to the practice of sex hormone replacement therapies in older men. Recent data suggest that androgen prescription rates in the US for men older than 60 years of age quadrupled from the years 2001 to 2011. While prescription sales of testosterone have increased from $150 million in 2000 to $1.8 billion in 2011, a significant portion of men prescribed testosterone replacement therapy did not meet the laboratory criteria for hypogonadism. While some clinical trials reported an association between testosterone insufficiency in older men and increased risk of death, the exact effects and consequences of testosterone replacement therapy, specifically in older men, remain unclear. This review is aimed at discussing the possible benefits and complications of testosterone replacement therapy in older men over 60 years of age.


Assuntos
Androgênios/uso terapêutico , Terapia de Reposição Hormonal , Hipogonadismo/tratamento farmacológico , Testosterona/uso terapêutico , Idoso , Terapia de Reposição Hormonal/efeitos adversos , Terapia de Reposição Hormonal/métodos , Humanos , Hipogonadismo/metabolismo , Masculino , Pessoa de Meia-Idade , Medição de Risco , Resultado do Tratamento
5.
J Clin Endocrinol Metab ; 103(4): 1678-1685, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29373734

RESUMO

Background: Serum testosterone levels and insulin sensitivity both decrease with age. Severe testosterone deficiency is associated with the development of insulin resistance. However, the effects of long-term testosterone administration on insulin sensitivity in older men with low or low-normal testosterone levels remain unknown. Methods: The Testosterone Effects on Atherosclerosis in Aging Men Trial was a placebo-controlled, randomized, double-blind trial. The participants were 308 community-dwelling men, ≥60 years old, with total testosterone 100 to 400 ng/dL or free testosterone <50 pg/mL. A subset of 134 nondiabetic men (mean age, 66.7 ± 5.1 years) underwent an octreotide insulin suppression test at baseline and at 3 and 36 months after randomization to measure insulin sensitivity. Insulin sensitivity was estimated as the steady-state plasma glucose (SSPG) concentration at equilibrium during octreotide and insulin administration. Secondary outcomes included total lean mass (TLM) and total fat mass (TFM) by dual energy x-ray absorptiometry. Results: There was a significant (P = 0.003) increase in SSPG in the placebo group, whereas no change was seen in testosterone-treated subjects from baseline to 36 months; however, the between-group differences in change in SSPG over 3 years were not statistically significant (+15.3 ± 6.9 mg/dL in the placebo group vs +6.2 ± 6.4 mg/dL in the testosterone group; mixed-model effect, P = 0.17). Changes in SSPG with testosterone treatment were not associated with changes in serum total or free testosterone concentrations. Changes in TFM but not TLM were associated with increases in SSPG. Stratification by age or baseline total testosterone level did not show significant intervention effects. Conclusion: Testosterone administration for 36 months in older men with low or low-normal testosterone levels did not improve insulin sensitivity.


Assuntos
Glicemia/análise , Composição Corporal/efeitos dos fármacos , Resistência à Insulina/fisiologia , Testosterona/administração & dosagem , Idoso , Método Duplo-Cego , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Testosterona/sangue , Resultado do Tratamento
6.
J Clin Endocrinol Metab ; 103(8): 2861-2869, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29846604

RESUMO

Context: Testosterone increases skeletal muscle mass and strength, but long-term effects of testosterone supplementation on aerobic capacity, or peak oxygen uptake (V̇O2peak), in healthy older men with low testosterone have not been evaluated. Objective: To determine the effects of testosterone supplementation on V̇O2peak during incremental cycle ergometry. Design: A double-blind, randomized, placebo-controlled, parallel-group trial (Testosterone's Effects on Atherosclerosis Progression in Aging Men). Setting: Exercise physiology laboratory. Participants: Healthy men aged ≥ 60 years with total testosterone levels of 100 to 400 ng/dL (3.5 to 13.9 nmol/L) or free testosterone levels < 50 pg/mL (174 pmol/L). Interventions: Randomization to 1% transdermal testosterone gel adjusted to achieve serum levels of 500 to 950 ng/dL or placebo applied daily for 3 years. Main Outcome Measures: Change in V̇O2peak. Results: Mean (±SD) baseline V̇O2peak was 24.2 ± 5.2 and 23.6 ± 5.6 mL/kg/min for testosterone and placebo, respectively. V̇O2peak did not change in men treated with testosterone but fell significantly in men receiving placebo (average 3-year decrease, 0.88 mL/kg/min; 95% CI, -1.39 to 0.38 mL/kg/min; P = 0.035); the difference in change in V̇O2peak between groups was significant (average 3-year difference, 0.91 mL/kg/min; 95% CI, 0.010 to 0.122 mL/kg/min; P = 0.008). The 1-g/dL mean increase in hemoglobin (P < 0.001) was significantly associated with changes in V̇O2peak in testosterone-treated men. Conclusion: The mean 3-year change in V̇O2peak was significantly smaller in men treated with testosterone than in men receiving placebo and was associated with increases in hemoglobin. The difference in V̇O2peak change between groups may indicate attenuation of its expected age-related decline; the clinical meaningfulness of the modest treatment effect remains to be determined.


Assuntos
Envelhecimento/metabolismo , Aterosclerose/patologia , Hipogonadismo/tratamento farmacológico , Pulmão/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Testosterona/uso terapêutico , Idoso , Envelhecimento/sangue , Envelhecimento/efeitos dos fármacos , Aterosclerose/complicações , Aterosclerose/fisiopatologia , Composição Corporal/efeitos dos fármacos , Composição Corporal/fisiologia , Progressão da Doença , Método Duplo-Cego , Terapia de Reposição Hormonal , Humanos , Hipogonadismo/complicações , Hipogonadismo/metabolismo , Hipogonadismo/fisiopatologia , Pulmão/fisiologia , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/efeitos dos fármacos , Placebos , Fatores de Tempo
7.
J Clin Endocrinol Metab ; 102(2): 583-593, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27754805

RESUMO

Context: Findings of studies of testosterone's effects on muscle strength and physical function in older men have been inconsistent; its effects on muscle power and fatigability have not been studied. Objective: To determine the effects of testosterone administration for 3 years in older men on muscle strength, power, fatigability, and physical function. Design, Setting, and Participants: This was a double-blind, placebo-controlled, randomized trial of healthy men ≥60 years old with total testosterone levels of 100 to 400 ng/dL or free testosterone levels <50 pg/mL. Interventions: Random assignment to 7.5 g of 1% testosterone or placebo gel daily for 3 years. Outcome Measures: Loaded and unloaded stair-climbing power, muscle strength, power, and fatigability in leg press and chest press exercises, and lean mass at baseline, 6, 18, and 36 months. Results: The groups were similar at baseline. Testosterone administration for 3 years was associated with significantly greater performance in unloaded and loaded stair-climbing power than placebo (mean estimated between-group difference, 10.7 W [95% confidence interval (CI), -4.0 to 25.5], P = 0.026; and 22.4 W [95% CI, 4.6 to 40.3], P = 0.027), respectively. Changes in chest-press strength (estimated mean difference, 16.3 N; 95% CI, 5.5 to 27.1; P < 0.001) and power (mean difference 22.5 W; 95% CI, 7.5 to 37.5; P < 0.001), and leg-press power were significantly greater in men randomized to testosterone than in those randomized to placebo. Lean body mass significantly increased more in the testosterone group. Conclusion: Compared with placebo, testosterone replacement in older men for 3 years was associated with modest but significantly greater improvements in stair-climbing power, muscle mass, and power. Clinical meaningfulness of these treatment effects and their impact on disability in older adults with functional limitations remains to be studied.


Assuntos
Envelhecimento/fisiologia , Composição Corporal/fisiologia , Terapia de Reposição Hormonal/métodos , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Aptidão Física/fisiologia , Testosterona/sangue , Testosterona/farmacologia , Idoso , Envelhecimento/sangue , Envelhecimento/efeitos dos fármacos , Composição Corporal/efeitos dos fármacos , Índice de Massa Corporal , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Testosterona/administração & dosagem
8.
J Clin Endocrinol Metab ; 102(5): 1478-1485, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-27992261

RESUMO

Context: Endogenous testosterone levels have been negatively associated with QTc interval in small case series; the effects of testosterone therapy on electrocardiographic parameters have not been evaluated in randomized trials. Objective: To evaluate the effects of testosterone replacement on corrected QT interval (QTcF) in two randomized controlled trials. Participants: Men with pre- and postrandomization electrocardiograms (ECGs) from the Testosterone and Pain (TAP) and the Testosterone Effects on Atherosclerosis in Aging Men (TEAAM) Trials. Interventions: Participants were randomized to either placebo or testosterone gel for 14 weeks (TAP) or 36 months (TEAAM). ECGs were performed at baseline and at the end of interventions in both trials; in the TEAAM trial ECGs were also obtained at 12 and 24 months. Outcomes: Difference in change in the QTcF between testosterone and placebo groups was assessed in each trial. Association of changes in testosterone levels with changes in QTcF was analyzed in men assigned to the testosterone group of each trial. Results: Mean total testosterone levels increased in the testosterone group of both trials. In the TAP trial, there was a nonsignificant reduction in mean QTcF in the testosterone group compared with placebo (effect size = -4.72 ms; P = 0.228) and the changes in QTcF were negatively associated to changes in circulating testosterone (P = 0.036). In the TEAAM trial, testosterone attenuated the age-related increase in QTcF seen in the placebo group (effect size= -6.30 ms; P < 0.001). Conclusion: Testosterone replacement attenuated the age-related increase in QTcF duration in men. The clinical implications of these findings require further investigation.


Assuntos
Envelhecimento , Androgênios/uso terapêutico , Terapia de Reposição Hormonal , Hipogonadismo/tratamento farmacológico , Testosterona/uso terapêutico , Administração Cutânea , Adulto , Idoso , Analgésicos Opioides/efeitos adversos , Método Duplo-Cego , Eletrocardiografia , Humanos , Hipogonadismo/induzido quimicamente , Hipogonadismo/fisiopatologia , Masculino , Pessoa de Meia-Idade
9.
Lancet Diabetes Endocrinol ; 4(8): 657-665, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27377542

RESUMO

BACKGROUND: The effects of testosterone on cognitive function in older men are incompletely understood. We aimed to establish the effects of long-term testosterone administration on multiple domains of cognitive function in older men with low or low-to-normal testosterone concentrations. METHODS: We did the randomised, double-blind, placebo-controlled, parallel-group TEAAM trial at three medical centres in Boston, Phoenix, and Los Angeles, USA. Men aged 60 years and older with low or low-to-normal testosterone concentrations (3·47-13·9 nmol/L, or free testosterone <173 pmol/L) were randomly assigned (1:1), via computer-generated randomisation, to receive either 7·5 g of 1% testosterone gel or placebo gel daily for 3 years. Randomisation was stratified by age (60-75 years vs >75 years) and study site. The testosterone dose was adjusted to achieve concentrations of 17·3-31·2 nmol/L. Participants and all study personnel were masked to treatment allocation. Multiple domains of cognitive function were assessed as prespecified secondary outcomes by use of standardised tests at baseline and months 6, 18, and 36. We did analyses by intention to treat (in men who had baseline assessments of cognitive function) and per protocol (restricted to participants who completed the study drug and had both baseline and 36 month assessments of cognitive function). The TEAAM trial is registered with ClinicalTrials.gov, number NCT00287586. FINDINGS: Between Sept 1, 2004, and Feb 12, 2009, we randomly assigned 308 participants to receive either testosterone (n=156) or placebo (n=152). 280 men had baseline cognitive assessments (n=140 per group). Mean follow-up time was 29·0 months (SD 11·5) in the testosterone group and 31·1 months (9·5) in the placebo group. The last participant completed the study on May 11, 2012. In the testosterone group, mean concentrations of serum total testosterone increased from 10·6 nmol/L (SD 2·2) to 19·7 nmol/L (9·2) and free testosterone concentrations increased from 222 pmol/L (62) to 364 pmol/L (222). In the placebo group, mean concentrations of serum total testosterone were 10·7 nmol/L (SD 2·3) at baseline and 11·1 nmol/L (3·2) post-intervention and free testosterone concentrations were 210 pmol/L (61) and 172 pmol/L (49), respectively. We recorded no between-group differences in changes in visuospatial ability (mean difference: Complex Figure Test -0·51, 95% CI -2·0 to 1·0), phonemic or category verbal fluency (phonemic fluency test 0·90, -1·3 to 3·1; categorical fluency test 1·1, -0·3 to 2·6), verbal memory (paragraph recall test 0·29, -1·2 to 1·8), manual dexterity (Grooved Pegboard Test 4·2, -1·3 to 9·7), and attention or executive function (Stroop Interference Test -2·6, -7·4 to 2·3) after adjustment for age, education, and baseline cognitive function. In both the intention-to-treat and per-protocol (n=86 per group) populations, changes in cognitive function scores were not related significantly to changes in total or free testosterone, or oestradiol concentrations. INTERPRETATION: Testosterone administration for 36 months in older men with low or low-to-normal testosterone concentrations did not improve cognitive function. Future long-term trials are needed to investigate the efficacy of testosterone replacement in patients with impaired cognition, such as people with Alzheimer's disease. FUNDING: AbbVie Pharmaceuticals, Aurora Foundation, Boston Claude D Pepper Older Americans Independence Center, and Boston University's Clinical and Translational Science Institute.


Assuntos
Cognição/efeitos dos fármacos , Testosterona/administração & dosagem , Idoso , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
10.
Free Radic Biol Med ; 35(10): 1301-9, 2003 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-14607529

RESUMO

To assess novel liquid chromatography/mass spectrometric methods for measuring oxidative damage to nucleic acids and lipids, we compared urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG), 5-hydroxymethyl-2'-deoxyuridine (5-OHmU), and 8-hydroxyguanosine (8-OxoG), and an isoprostane, 8-iso-prostaglandin F(2)alpha (IsopF(2)alpha) in 234 healthy men (n = 113) and women (n = 121), 80 current smokers, 96 never-smokers), and 58 ex-smokers (no tobacco use for 3 years). The 8-OHdG and 8-OxoG did not differ significantly by group; 5-OHmU was higher in smokers, compared with ex- (p <.003) and never- (p <.0001) smokers and in ex- vs. never-smokers (p =.014) at, respectively, 13.5 +/- 0.7, 11.3 +/- 1.0, and 8.7 +/- 0.3 microg/g creatinine. IsopF(2)alpha was higher in smokers, compared with ex- (p =.007) and never-smokers (p <.0001) and in ex- vs. never- smokers (p =.002) at, respectively, 1.1 +/- 0.10; 0.74 +/- 0.07, and 0.51 +/- 0.04 microg/g creatinine. There were significant correlations among all three nucleic acid adducts and between IsopF(2)alpha and both 5-OHmU and 8-OHdG. Many smokers and ex-smokers had high levels of either 5-OHmU excretion or IsopF(2)alpha excretion, but not both. We conclude that 5-OHmU and IsopF(2)alpha are more discriminating of oxidative stress from tobacco smoke than the other two compounds measured. Whether characteristic patterns of excretion of these indicators forecast differential disease risk should be explored in future research.


Assuntos
Adutos de DNA/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/urina , Dinoprosta/urina , Guanosina/análogos & derivados , Guanosina/urina , Fumar/metabolismo , Timidina/análogos & derivados , Timidina/urina , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida , Dinoprosta/análogos & derivados , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Oxirredução , Estresse Oxidativo , Distribuição por Sexo , Fumar/efeitos adversos
13.
Nutr Res ; 29(12): 846-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19963157

RESUMO

The antiglycemic effects of vinegar have been known for more than a century and have been demonstrated in animal as well as human studies. Although the exact mechanism of vinegar action is not known, several possibilities have been proposed including suppression of disaccharidase activity, delayed gastric emptying, enhanced glucose uptake in the periphery and conversion to glycogen, and increased satiety. We hypothesized that by suppressing endogenous insulin secretion, we could estimate the glucose absorption rate from an oral carbohydrate load and determine the effects of vinegar ingestion on this rate. To do so, 5 subjects had 4 studies at 1-week intervals, randomly receiving placebo twice (60 mL water) and vinegar twice (20 mL apple cider vinegar, 40 mL water), followed 2 minutes later by a meal of mashed potatoes (0.75 g carbohydrate per kilogram body weight) that was consumed over 20 minutes. At the beginning of the meal, an oral octreotide/insulin suppression test (25-microg bolus octreotide; 180 minute infusion 5 mU/m(2) body surface area per minute regular human insulin, and 0.5 microg/min octreotide) was begun. Blood samples for insulin and glucose were drawn at 20-minute intervals. The oral octreotide/insulin suppression test suppressed endogenous insulin secretion for the first 100 minutes of the study. During this time, the rate of rise of glucose was modestly but significantly (P = .01) greater after vinegar ingestion compared to placebo, suggesting that vinegar does not act to decrease glycemia by interference with enteral carbohydrate absorption.


Assuntos
Ácido Acético/metabolismo , Carboidratos da Dieta/metabolismo , Hipoglicemiantes/metabolismo , Absorção Intestinal , Adulto , Idoso , Área Sob a Curva , Glicemia/análise , Técnicas de Diagnóstico Endócrino , Feminino , Humanos , Infusões Intravenosas , Insulina/administração & dosagem , Insulina/sangue , Insulina/farmacologia , Antagonistas da Insulina/farmacologia , Masculino , Pessoa de Meia-Idade , Octreotida/farmacologia
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