RESUMO
BACKGROUND: Nicotinamide adenine dinucleotide (NAD) precursors, nicotinamide mononucleotide (NMN), or nicotinamide riboside (NR) extend healthspan and ameliorate some age-related conditions in model organisms. However, early-phase trials of NAD precursors have yielded varying results and their pharmacokinetics remain incompletely understood. Here, we report the pharmacokinetics and pharmacodynamics of MIB-626, a microcrystalline unique polymorph ßNMN formulation. METHODS: In this double-blind, placebo-controlled study, 32 overweight or obese adults, 55-80 years, were block-randomized, stratified by sex, to 1 000-mg MIB-626 once daily, twice daily, or placebo for 14 days. NMN, NAD, and NAD metabolome were measured using liquid chromatography-tandem mass spectrometry. RESULTS: Participant characteristics were similar across groups. MIB-626 was well tolerated and frequency of adverse events was similar across groups. Blood NMN concentrations on Day 14 in MIB-626-treated groups were significantly higher compared to placebo (1.7-times and 3.7-times increase above baseline in 1 000 mg once-daily and twice-daily groups in mean AUClast, respectively). MIB-626 treatment was associated with substantial dose-related increases in blood NAD levels. Blood levels of NAD metabolites were higher in NMN-treated participants on Days 8 and 14 than at baseline. Changes in NMN or NAD levels were not related to sex, body mass index, or age. Very little unmodified NMN was excreted in the urine. CONCLUSION: MIB-626 1 000 mg once-daily or twice-daily regimens were safe and associated with substantial dose-related increases in blood NAD levels and its metabolome. These foundational data that were obtained using a pharmaceutical-grade ßNMN, standardized sample collection, and validated liquid chromatography-tandem mass spectrometry assays, should facilitate design of efficacy trials in disease conditions.
Assuntos
NAD , Mononucleotídeo de Nicotinamida , Humanos , Pessoa de Meia-Idade , Idoso , NAD/metabolismo , Mononucleotídeo de Nicotinamida/metabolismo , Mononucleotídeo de Nicotinamida/farmacologia , Metaboloma , Espectrometria de Massas , Índice de Massa CorporalRESUMO
PURPOSE: Precise evaluation of serum testosterone levels is important in making an accurate diagnosis of androgen deficiency. Recent practice guidelines on male androgen deficiency recommend that testosterone be measured in the morning while fasting. Although there is ample evidence regarding morning measurement of testosterone, studies that evaluated the effect of glucose load or meals were limited by inclusion of hypogonadal or diabetic men, and measurement of testosterone was not performed using mass spectrometry. METHODS: Sixty men (23-97 years) without pre-diabetes or diabetes who had normal total testosterone (TT) levels underwent either an oral glucose tolerance test (OGTT) or a mixed meal tolerance test (MMTT) after an overnight fast. Serum samples were collected before and at regular intervals for 2 h (OGTT cohort) or 3 h (MMTT cohort). TT was measured by LC-MS/MS. LH and prolactin were also measured. RESULTS: TT decreased after a glucose load (mean drop at nadir = 100 ng/dL) and after a mixed meal (drop at nadir = 123 ng/dL). Approximately 11% of men undergoing OGTT and 56% undergoing MMTT experienced a transient decrease in TT below 300 ng/dL, the lower normal limit. Testosterone started declining 20 min into the tests, with average maximum decline at 60 min. Most men still had TT lower than baseline at 120 min. This effect was independent of changes in LH or prolactin. CONCLUSION: A glucose load or a mixed meal transiently, but significantly, lowers TT levels in healthy, non-diabetic eugonadal men. These findings support the recommendations that measurement of serum testosterone to diagnose androgen deficiency should be performed while fasting.
Assuntos
Glucose/farmacologia , Carga Glicêmica , Refeições , Testosterona/sangue , Adulto , Glicemia/análise , Estudos de Coortes , Teste de Tolerância a Glucose , Voluntários Saudáveis , Humanos , Insulina/sangue , Estudos Longitudinais , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Prolactina/sangue , Adulto JovemRESUMO
CONTEXT: Androgen deprivation therapy (ADT) for prostate cancer (PCa) is associated with increased cardiovascular mortality and sudden cardiac death, with some events occurring early after initiation of ADT. Testosterone levels are inversely associated with corrected QT (QTc) interval duration; therefore, prolongation of QTc duration could be responsible for some of these events during ADT. OBJECTIVE: To evaluate changes in QTc duration during ADT. DESIGN AND INTERVENTIONS: A 6-month prospective cohort study that enrolled men with PCa about to undergo ADT (ADT group) and a control group of men who previously underwent prostatectomy for PCa and never received ADT (non-ADT group). PATIENTS: At study entry, all participants were eugonadal and had no history of cardiac arrhythmias or complete bundle branch block. OUTCOMES: Difference in change in QTc duration from baseline on a 12-lead electrocardiogram at 6, 12, and 24 weeks after initiation of ADT compared with electrocardiograms performed at the same intervals in the non-ADT group. PR, QRS, and QT interval durations were also evaluated. RESULTS: Seventy-one participants formed the analytical sample (33 ADT and 38 non-ADT). ADT was associated with prolongation of the QTc by 7.4 ms compared with the non-ADT group [95% confidence interval (CI) 0.08 to 14.7 ms; P = 0.048]. ADT was also associated with shortening of the QRS interval by 2.4 ms (95% CI -4.64 to -0.23; P = 0.031). Electrolytes did not change. CONCLUSIONS: Men undergoing ADT for PCa experienced prolongation of the QTc. These findings might explain the increased risk of sudden cardiac death seen in these patients.
RESUMO
Importance: The Institute of Medicine set the recommended dietary allowance (RDA) for protein at 0.8 g/kg/d for the entire adult population. It remains controversial whether protein intake greater than the RDA is needed to maintain protein anabolism in older adults. Objective: To investigate whether increasing protein intake to 1.3 g/kg/d in older adults with physical function limitations and usual protein intake within the RDA improves lean body mass (LBM), muscle performance, physical function, fatigue, and well-being and augments LBM response to a muscle anabolic drug. Design, Setting, and Participants: This randomized clinical trial with a 2 × 2 factorial design was conducted in a research center. A modified intent-to-treat analytic strategy was used. Participants were 92 functionally limited men 65 years or older with usual protein intake less thanor equal to 0.83 g/kg/d within the RDA. The first participant was randomized on September 21, 2011, and the last participant completed the study on January 19, 2017. Interventions: Participants were randomized for 6 months to controlled diets with 0.8 g/kg/d of protein plus placebo, 1.3 g/kg/d of protein plus placebo, 0.8 g/kg/d of protein plus testosterone enanthate (100 mg weekly), or 1.3 g/kg/d of protein plus testosterone. Prespecified energy and protein contents were provided through custom-prepared meals and supplements. Main Outcomes and Measures: The primary outcome was change in LBM. Secondary outcomes were muscle strength, power, physical function, health-related quality of life, fatigue, affect balance, and well-being. Results: Among 92 men (mean [SD] age, 73.0 [5.8] years), the 4 study groups did not differ in baseline characteristics. Changes from baseline in LBM (0.31 kg; 95% CI, -0.46 to 1.08 kg; P = .43) and appendicular (0.04 kg; 95% CI, -0.48 to 0.55 kg; P = .89) and trunk (0.24 kg; 95% CI, -0.17 to 0.66 kg; P = .24) lean mass, as well as muscle strength and power, walking speed and stair-climbing power, health-related quality of life, fatigue, and well-being, did not differ between men assigned to 0.8 vs 1.3 g/kg/d of protein regardless of whether they received testosterone or placebo. Fat mass decreased in participants given higher protein but did not change in those given the RDA: between-group differences were significant (difference, -1.12 kg; 95% CI, -2.04 to -0.21; P = .02). Conclusions and Relevance: Protein intake exceeding the RDA did not increase LBM, muscle performance, physical function, or well-being measures or augment anabolic response to testosterone in older men with physical function limitations whose usual protein intakes were within the RDA. The RDA for protein is sufficient to maintain LBM, and protein intake exceeding the RDA does not promote LBM accretion or augment anabolic response to testosterone. Trial Registration: clinicaltrials.gov Identifier: NCT01275365.
Assuntos
Atividades Cotidianas , Composição Corporal , Proteínas Alimentares/administração & dosagem , Nível de Saúde , Saúde Mental , Força Muscular , Qualidade de Vida , Absorciometria de Fóton , Afeto , Idoso , Idoso de 80 Anos ou mais , Androgênios/uso terapêutico , Método Duplo-Cego , Fadiga , Humanos , Vida Independente , Masculino , Recomendações Nutricionais , Testosterona/análogos & derivados , Testosterona/uso terapêuticoRESUMO
CONTEXT: Previous animal and human research suggests that testosterone has antinociceptive properties. Castration in male rodents increases pain perception which is reversed by testosterone replacement. Pain perception also improves in hypogonadal men with testosterone therapy. However, it remains unclear whether androgen deprivation therapy (ADT) in men with prostate cancer (PCa) is associated with an increase in pain perception. OBJECTIVES: To evaluate the effects of ADT on pain perception, depression and quality of life (QOL) in men with PCa. METHODS: Thirty-seven men with PCa about to undergo ADT with leuprolide acetate (ADT group) were followed prospectively for six months to evaluate changes in clinical and experimental pain. Forty men who had previously undergone prostatectomy for localized PCa and were in remission served as controls (non-ADT group). All participants were eugonadal at study entry. Primary outcomes were changes in clinical pain (assessed with Brief Pain Inventory questionnaire) and experimental pain (assessed with quantitative sensory testing). Secondary outcomes included evaluation of depression, anxiety levels, and quality of life. RESULTS: Serum testosterone levels significantly decreased in the ADT group but remained unchanged in the non-ADT group. There were no significant changes in pain thresholds, ratings, or other responses to quantitative sensory tests over the 6-month course of the study. Clinical pain did not differ between the two groups, and no changes from baseline were observed in either group. Men undergoing ADT did experience worsening of depression (0.93; 95% CI = 0.04-1.82; P = 0.042) and QOL related to physical role limitation (-18.28; 95% CI = -30.18 to -6.37; P = 0.003). CONCLUSION: ADT in men with PCa is associated with worsening of depression scores and QOL but is not associated with changes in clinical pain or pain sensitivity.
Assuntos
Antagonistas de Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Depressão , Percepção da Dor/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/psicologia , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/efeitos adversos , Antineoplásicos Hormonais/efeitos adversos , Depressão/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Limiar da Dor/efeitos dos fármacos , Limiar da Dor/fisiologia , Estudos Prospectivos , Qualidade de Vida , Testosterona/sangue , Resultado do TratamentoRESUMO
The dietary protein allowance for older men to maintain lean body mass and muscle strength and to accrue optimal anabolic responses to promyogenic stimuli is poorly characterized. The OPTIMEN trial was designed to assess in older men with moderate physical dysfunction and insufficient habitual protein intake (Assuntos
Androgênios/farmacologia
, Composição Corporal/fisiologia
, Proteínas Alimentares/administração & dosagem
, Força Muscular/fisiologia
, Músculo Esquelético/metabolismo
, Testosterona/análogos & derivados
, Absorciometria de Fóton
, Idoso
, Índice de Massa Corporal
, Método Duplo-Cego
, Ingestão de Energia
, Humanos
, Masculino
, Projetos de Pesquisa
, Testosterona/farmacologia
RESUMO
OBJECTIVE: To determine dose-dependent effects of T administration on voice changes in women with low T levels. METHODS: Seventy-one women who have undergone a hysterectomy with or without oophorectomy with total T < 31 ng/dL and/or free T < 3.5 pg/mL received a standardized transdermal estradiol regimen during the 12-week run-in period and were then randomized to receive weekly im injections of placebo or 3, 6.25, 12.5, or 25 mg T enanthate for 24 weeks. Total and free T levels were measured by liquid chromatography-tandem mass spectrometry and equilibrium dialysis, respectively. Voice handicap was measured by self-report using a validated voice handicap index questionnaire at baseline and 24 weeks after intervention. Functional voice testing was performed using the Kay Elemetrics-Computer Speech Lab to determine voice frequency, volume, and harmonics. RESULTS: Forty-six women with evaluable voice data at baseline and after intervention were included in the analysis. The five groups were similar at baseline. Mean on-treatment nadir total T concentrations were 13, 83, 106, 122, and 250 ng/dL in the placebo, 3-, 6.25-, 12.5-, and 25-mg groups, respectively. Analyses of acoustic voice parameters revealed significant lowering of average pitch in the 12.5- and 25-mg dose groups compared to placebo (P < .05); these changes in pitch were significantly related to increases in T concentrations. No significant dose- or concentration-dependent changes in self-reported voice handicap index scores were observed. CONCLUSION: Testosterone administration in women with low T levels over 24 weeks was associated with dose- and concentration-dependent decreases in average pitch in the higher dose groups. These changes were seen despite the lack of self-reported changes in voice.