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2.
J Endocrinol Invest ; 36(11): 955-64, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23698556

ABSTRACT

BACKGROUND: In females, estrogen is a potential modulator of cortisol response to stressors. The aim of this study was to determine the influence of menstrual cycle phase, oral contraception (OC) use and exercise training on hypothalamo-pituitary-adrenal (HPA) axis activity and reactivity after physical stress. AIM: We investigated the effects of the menstrual cycle and OC use on exhaustive exerciseinduced changes in free salivary cortisol concentrations and free urinary cortisol/cortisone excretion in healthy young women. MATERIALS AND SUBJECTS: Twenty-eight women were allocated to an untrained group (no.=16) or a trained group (no.=12), depending on their physical training background. The untrained group was composed of nine OC users (UNTOC+) and seven eumenorrheic women (UNT-OC-) tested in the follicular and luteal phases, while the trained group was entirely composed of OC+ subjects (T-OC+). METHODS: Three laboratory sessions were conducted in a randomised order: a prolonged exercise test, a short-term exercise test, and a control session. For each session, urine and saliva specimens were collected at rest (09:00 h) and then, 30, 60 and 90 min later. RESULTS: Estradiol fluctuation during the menstrual cycle phase did not alter free cortisol baseline values and responses to exercise. OC use was associated with increased free resting salivary concentrations and urinary cortisol excretion with blunted salivary cortisol response to prolonged exercise stimulation. No training effect was noted. CONCLUSIONS: OC but not menstrual cycle phase is associated with increased free cortisol levels and low HPA axis reactivity.


Subject(s)
Contraceptives, Oral/pharmacology , Exercise/physiology , Hydrocortisone/metabolism , Hypothalamo-Hypophyseal System/drug effects , Menstrual Cycle/physiology , Pituitary-Adrenal System/drug effects , Exercise Test , Female , Humans , Hydrocortisone/urine , Saliva/metabolism , Stress, Psychological , Young Adult
3.
Anal Bioanal Chem ; 396(3): 1167-76, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19943160

ABSTRACT

Metabolomics is a comprehensive method for metabolite assessment that involves measuring the overall metabolic signature of biological samples. We used this approach to investigate biochemical changes due to acute and chronic physical exercise. Twenty-two women using identical oral contraceptives were segregated into an untrained (n = 10) or trained (n = 12) group depending on their physical training background. The subjects performed two exercises in a randomized order: a prolonged exercise test (75% of their VO(2 max) until exhaustion) and a short-term, intensive exercise test (short-term, intensive exercise anaerobic test). Urine specimens were collected before and 30 min after each test. The samples were analyzed by (1)H NMR spectroscopy, and multivariate statistical techniques were utilized to process the data. Distinguishing characteristics were observed only in the urine profiles of specimens collected before vs. 30 min after the short-term, intensive exercise test. The metabolites responsible for such changes were creatinine, lactate, pyruvate, alanine, beta-hydroxybutyrate, acetate, and hypoxanthine. In both groups, the excretion of lactate, pyruvate, alanine, beta-hydroxybutyrate, and hypoxanthine increased similarly after the completion of the short-term, intensive exercise test (p < 0.03). However, acetate excretion increased to a lesser extent in trained than in untrained subjects (p < 0.05). In conclusion, metabolomics is a promising tool in order to gain insight into physiological status and to clarify the changes induced by short-term, intense physical exercise.


Subject(s)
Exercise , Magnetic Resonance Spectroscopy , Metabolome , Metabolomics , Urine/chemistry , Adult , Exercise Test , Female , Humans , Magnetic Resonance Spectroscopy/methods , Metabolomics/methods , Young Adult
4.
Scand J Med Sci Sports ; 20(1): 90-9, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19170961

ABSTRACT

We investigated the effects of the menstrual cycle, oral contraception and physical training on exhaustive exercise-induced changes in the excretion of nandrolone metabolites [19-norandrosterone (19-NA), and 19-noretiocholanolone (19-NE)] in young women. Twenty-eight women were allocated to an untrained group (n=16) or a trained group (n=12), depending on their physical training background. The untrained group was composed of nine oral contraceptive users (OC+) and seven eumenorrheic women (OC-), while the trained group was entirely composed of OC+ subjects. Three laboratory sessions were conducted in a randomized order: a prolonged exercise test, a short-term exercise test and a control session. Urine specimens were collected before and 30, 60 and 90 min after the exercise test and at the same times of the day during the control session. Urinary concentrations of nandrolone metabolites were determined by gas chromatography coupled to mass spectrometry. Urinary concentrations of 19-NA and 19-NE ranged from undetectable levels to 1.14 and 0.47 ng/mL, respectively. Nandrolone excretion was not affected by the menstrual cycle phase (early follicular vs mid-luteal), prior physical training, oral contraception or acute physical exercise. Therefore, a urinary concentration of 2 ng/mL of 19-NA appears to be fair as the upper acceptable limit in doping control tests for female athletes.


Subject(s)
Exercise/physiology , Nandrolone/urine , Adolescent , Adult , Androsterone/urine , Contraceptives, Oral/pharmacology , Creatinine/metabolism , Doping in Sports , Etiocholanolone/urine , Exercise Test , Female , Follicular Phase/urine , Humans , Luteal Phase/urine , Oxygen Consumption , Young Adult
5.
Eur J Appl Physiol ; 106(3): 365-73, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19280215

ABSTRACT

The objective of this study was to ascertain the effects of menstrual cycle, oral contraception, and training status on the exercise-induced changes in circulating DHEA-sulphate and testosterone in young women. Twenty-eight healthy women were assigned to an untrained group (n = 16) or a trained group (n = 12) depending on their training background. The untrained group was composed of nine oral contraceptive users (OC+) and seven eumenorrheic women (OC-). The trained group was composed of OC+ subjects only. All the OC+ subjects were taking the same low-dose oral contraception. Three laboratory sessions were organised in a randomised order: a prolonged exercise test until exhaustion, a short-term exhaustive exercise test, and a control session. Blood specimens were collected before, during and after the exercise tests and at the same time of the day during the control session. Basal circulating testosterone was significantly lower in trained as compared to untrained subjects. In all subjects, the prolonged exhaustive exercise induced a significant increase in circulating DHEA-s and testosterone. The short-term exercise induced a significant increase in circulating DHEA-s in untrained eumenorrheic and in trained OC users only. Menstrual phases in OC- did not influence the responses. It was found that exhaustive physical exercise induced an increase in circulating DHEA-s and testosterone in young women. Oral contraception may limit short-term exercise-induced changes.


Subject(s)
Contraceptives, Oral, Hormonal/pharmacology , Dehydroepiandrosterone Sulfate/blood , Exercise/physiology , Menstrual Cycle/drug effects , Menstruation/drug effects , Testosterone/blood , Age Factors , Bicycling/physiology , Blood Glucose/physiology , Contraception/methods , Contraceptives, Oral , Dehydroepiandrosterone/blood , Dietary Fats/adverse effects , Dose-Response Relationship, Drug , Exercise Test , Female , Humans , Menstrual Cycle/physiology , Menstruation/physiology
6.
Anal Bioanal Chem ; 393(4): 1315-25, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19096831

ABSTRACT

Dehydroepiandrosterone (DHEA) and its metabolite androsterone (A) are natural steroids secreted in high quantities in human body. To assess the influence of oral contraceptives, menstrual cycle phase, and also physical exercise (acute and chronic such as training) on these metabolites excretions, a collection of 28 female urine specimens was organized. A three-extraction-step method was developed, and the analyses were performed by gas chromatography-mass spectrometry using deuterated 19-noretiocholanolone as the internal standard. Sample hydration state was found to be of great importance for kinetic studies, as it directly influenced the concentrations. No influence of menstrual cycle and training was found for androsterone and DHEA. However, oral contraceptive intake lowered DHEA excretion in urine and A seems to be slightly affected by exercise.


Subject(s)
Androsterone/urine , Contraceptives, Oral , Dehydroepiandrosterone/urine , Exercise , Menstrual Cycle , Creatinine/urine , Female , Gas Chromatography-Mass Spectrometry , Humans , Sensitivity and Specificity
7.
Steroids ; 73(12): 1203-16, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18640139

ABSTRACT

The idea of the presence of androgens in females may sound peculiar as androgens generally refer to male hormones. Although produced in small amounts in women, androgens have direct and significant effects on many aspects of female physiology. Moreover, androgens are precursors to estrogens, which are the predominant female sex hormones. The measurement of androgens in blood is important in the diagnosis of both gonadal and adrenal functional disturbances, as well as monitoring subsequent treatments. The accuracy of such measurements is crucial in sports medicine and doping control. Therefore, the concentration of androgens in female subjects is frequently measured. Analysing such compounds with accuracy is especially difficult, costly and time consuming. Therefore, laboratories widely use direct radioimmunoassay kits, which are often insensitive and inaccurate. It is especially complicated to determine the level of androgens in women, as the concentration is much lower compared to the concentration found in males. Additionally, the amount of androgens in fluids tends to decrease with aging. Analyses of hormone concentrations are influenced by a myriad of factors. The factors influencing the outcome of these tests can be divided into in vivo preanalytical factors (e.g., aging, chronobiological rhythms, diet, menstrual cycle, physical exercise, etc.), in vitro preanalytical factors (e.g., specimen collection, equipment, transport, storage, etc.) and as mentioned before, analytical factors. To improve the value of these tests, the strongly influencing factors must be controlled. This can be accomplished using standardised assays and specimen collection procedures. In general, sufficient attention is not given to the preanalytical (biological) factors, especially in the measurement of androgens in females. Biological factors (non-pathological factors) that may influence the outcome of these tests in female subjects have received little attention and are the topic of the present review.


Subject(s)
Androgens/blood , Female , Humans , Radioimmunoassay
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