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1.
Horm Res Paediatr ; 96(4): 412-422, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36446347

RESUMEN

INTRODUCTION: 11-oxygenated C19 steroids (11-oxyandrogens) have been shown to rise during adrenarche and remain higher throughout adulthood than in early childhood. The patterns of circulating 11-oxyandrogens throughout normal puberty have not yet been described. METHODS: We conducted a secondary analysis of healthy youth participants, both males and females, enrolled in six prior endocrine studies (N = 249). Participants were classified according to Tanner stage and body mass index (BMI). Concentrations of three adrenal-specific 11-oxygenated androgens, 11ß-hydroxyandrostenedione (11OHA4), 11ß-hydroxytestosterone (11OHT), and 11-ketotestosterone (11KT), were measured in fasting serum samples. RESULTS: 11OHA4 and 11OHT increased modestly between early and late puberty in youth with normal weight (p < 0.05), whereas increases in 11KT did not reach statistical significance (p < 0.06). 11KT levels differed between sexes throughout puberty (p < 0.01), and changes in 11-oxyandrogens were small compared to the marked increases for estradiol in girls or testosterone in boys. The trajectories of 11KT and 11OHA4 changes throughout puberty differed by BMI category (p < 0.05). CONCLUSION: Beyond adrenarche, 11-oxyandrogens continue to rise during pubertal development. The differences in 11KT trajectories in males and females are small compared to changes in testosterone for males and estradiol for females during puberty. Obesity appears to influence the trajectories of 11-oxyandrogens during puberty.


Asunto(s)
Andrógenos , Testosterona , Masculino , Femenino , Adolescente , Preescolar , Humanos , Adulto , Obesidad , Pubertad , Estradiol
2.
J Endocr Soc ; 6(7): bvac037, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35611324

RESUMEN

Context: Polycystic ovary syndrome (PCOS) is common and diagnosis requires an elevated testosterone. The clinical importance of adrenal 11-oxyandrogens in PCOS is unclear. Objective: We sought to determine if 11-oxyandrogens 1) better identify PCOS diagnosis compared to testosterone, 2) predict clinical comorbidities of PCOS, and 3) are altered with an combined oral contraceptive pill (COCP) or metformin therapy. Methods: Data from 200 adolescent female participants aged 12 to 21 years, most with obesity, enrolled across 6 studies in pediatric endocrinology were included: 70 non-PCOS controls, 115 untreated PCOS, 9 PCOS + obesity treated with COCP, and 6 PCOS + obesity treated with metformin. 11-Hydroxyandrostenedione (11-OHA4), 11-hydroxytestosterone (1-OHT), 11-ketotestosterone (11-KT), and testosterone were measured with liquid chromatography-tandem mass spectrometry. Data between 1) untreated PCOS and controls and 2) untreated PCOS and the 2 treatment groups were compared. Results: Untreated girls with PCOS had higher 11-OHA4 (P = .003) and 11-OHT (P = .005) compared to controls, but not 11-KT (P = .745). Elevated 11-OHA4 remained statistically significant after controlling for obesity. Testosterone better predicted PCOS status compared to 11-oxyandrogens (receiver operating characteristic curve analysis: 11-OHA4 area under the curve [AUC] = 0.620, 11-OHT AUC = 0.638; testosterone AUC = 0.840). Among untreated PCOS patients, all 3 11-oxyandrogens correlated with hirsutism severity. 11-KT (P = .039) and testosterone (P < .006) were lower in those on COCP treatment compared to untreated PCOS. Metformin treatment had no effect on 11-oxyandrogens, although testosterone was lower (P = .01). Conclusion: Although 11-oxyandrogens do not aid in the diagnosis of PCOS, they relate to excess hair growth. COCP treatment may related to 11-KT; however, further work is needed to determine causality, relationship with metabolic outcomes, and the clinical utility of measuring these androgens in PCOS.

3.
J Biol Rhythms ; 28(1): 79-89, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23382594

RESUMEN

Melatonin is endogenously produced and released in humans during nighttime darkness and is suppressed by ocular light exposure. Exogenous melatonin is used to induce circadian phase shifts and sleep. The circadian phase-shifting ability of a stimulus (e.g., melatonin or light) relative to its timing may be displayed as a phase response curve (PRC). Published PRCs to exogenous melatonin show a transition from phase advances to delays approximately 1 h after dim light melatonin onset. A previously developed mathematical model simulates endogenous production and clearance of melatonin as a function of circadian phase, light-induced suppression, and resetting of circadian phase by light. We extend this model to include the pharmacokinetics of oral exogenous melatonin and phase-shifting effects via melatonin receptors in the suprachiasmatic nucleus of the mammalian hypothalamus. Model parameters are fit using 2 data sets: (1) blood melatonin concentration following a 0.3- or 5.0-mg dose, and (2) a PRC to a 3.0-mg dose of melatonin. After fitting to the 3.0-mg PRC, the model correctly predicts that, by comparison, the 0.5-mg PRC is slightly decreased in amplitude and shifted to a later circadian phase. This model also reproduces blood concentration profiles of various melatonin preparations that differ only in absorption rate and percentage degradation by first-pass hepatic metabolism. This model can simulate experimental protocols using oral melatonin, with potential application to guide dose size and timing to optimally shift and entrain circadian rhythms.


Asunto(s)
Ritmo Circadiano/efectos de los fármacos , Ritmo Circadiano/fisiología , Melatonina/farmacología , Modelos Biológicos , Sueño/efectos de los fármacos , Sueño/fisiología , Temperatura Corporal/efectos de los fármacos , Temperatura Corporal/fisiología , Oscuridad , Humanos , Luz , Melatonina/farmacocinética , Receptores de Melatonina/metabolismo , Núcleo Supraquiasmático/efectos de los fármacos , Núcleo Supraquiasmático/metabolismo , Núcleo Supraquiasmático/fisiología , Visión Ocular/efectos de los fármacos , Visión Ocular/fisiología
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