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Clinical Trial 2004; 25(5): 381-385 PubMed PMID: 15580174 Citation  Keywords:  Adult, Body Composition, Energy Metabolism:physiology, Exercise:physiology, Female, Humans, Leptin:blood, Obesity:blood, Physical Endurance:physiology, Physical Fitness:physiology,.   

OBJECTIVE: Recent studies have concluded that an energy expenditure by an acute exercise session has no immediate effect on leptin levels while some showed a decline in leptin levels. The purpose of this study was to investigate any possible effects of training status of the subjects on acute exercise-leptin relationship in obese patients.

MATERIALS AND METHODS: Fourteen obese sedentary females were enrolled to the study and effects of acute incremental exercise on serum leptin levels were determined at rest and at maximal exercise performance. Then, they participated to a 12-weeks endurance aerobic training programme performed in the laboratory on a computer controlled cycle ergometer and their leptin levels were re-evaluated and the leptin-acute exercise relationships obtained under different training levels in the same group of subjects were compared. The body compositions were determined by bioelectrical impedance. Pre and post training blood samples were taken at rest and at the maximal exercise performance. Serum leptin levels were analysed in duplicate by RIA. Data were evaluated using, paired t and Pearson's tests.

RESULTS: Leptin levels were not acutely affected by the incremental exercise either before (23.62+/-3.5 ng/ml and 22.62+/-3.6 ng/ml) or after (13.13+/-3.4 ng/ml and 13.82+/-3.6 ng/ml) endurance training. The marked decrease in leptin levels following training was closely correlated with fat mass loss R= 0.899 (P= 0.0001).

CONCLUSIONS: This study indicates that an increase in energy expenditure by acute exercise has no significant acute effect on leptin level regardless of the training status of the subjects and decrease in leptin levels after a 12-weeks endurance aerobic training programme are closely associated with the fat mass loss....

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Journal Article 2001; 22(2): 121-127 PubMed PMID: 11335888 Citation  Keywords:  Body Constitution, Body Mass Index, Bone and Bones:metabolism, Circadian Rhythm, Collagen:analysis, Collagen Type I, Female, Humans, Melatonin:analysis, Middle Aged, Obesity:metabolism, Osteoporosis, Postmenopausal:prevention & control, Peptide Fragments:.   

BACKGROUND: Few experimental and clinical studies show that melatonin (MEL) can play a significant part to modulate circadian bone metabolism. On this basis it was suggested that MEL secretion which altered during 24-h in obese women could be of importance to regulate bony mass defect after menopause.

OBJECTIVE: The aim of the study was to prove if there were any connection between changes in 24-h profile of serum MEL levels and circadian metabolism of type I collagen in postmenopausal women with visceral obesity.

METHODS: The relationship of 24-h profile of salivary MEL and circadian metabolism of type I collagen (as assessed by measuring saliva concentrations of carboxyterminal propeptide of type I procollagen--PICP and cross-linked carboxyterminal telopeptide of type I collagen--ICTP) was investigated in 26 women with visceral obesity (33.5 < BMI < 42.1 kg/m(2)) and 18 healthy volunteers with correct body mass (21 < BMI < 24.5 kg/m(2); 0.73 < WHR < 0.76). The specimens were collected at subjects' home at 3 h intervals during a 24 h span. The age range of all subjects was 52-60 years.

RESULTS: In all the obese women studied a tendency to suppress circadian levels of tested biochemical markers of bone metabolism was observed (especially regarding ICTP); those alterations were accompanied by substantial increment in MEL concentrations during the day. Significant and negative correlation was found between values of acrophase MEL and PICP rhythms and both amplitude and acrophase of MEL and ICTP rhythms.

CONCLUSION: Our results confirm hypothesis that alterations in MEL concentrations might have a protective effect against postmenopausal loss of bone mass....

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Journal Article 2018; 39(3): 219-225 PubMed PMID: 30431736 Citation  Keywords:  Adolescent, Adult, Body Mass Index, Estradiol:blood, Female, Humans, Menstruation Disturbances:blood, Obesity:blood, Oligomenorrhea:blood, Overweight:blood, Risk Factors, Sex Hormone-Binding Globulin:metabolism, Testosterone:blood, Vitamin D:analogs & der.   

INTRODUCTION: Vitamin D (VD) plays a crucial role in calcium metabolism as well as immunological and endocrine homeostasis. Previous studies revealed strong inverse correlation between VD levels and insulin resistance, parathyroid dysfunctions and autoimmune thyroid disease. Insufficient evidence concerns its dependency of ovarian hormones. Malfunctioning of the ovaries results in menstrual disorders that are one of the most common endocrine impairments in young women of reproductive age. MATERIAL AND METHODS: The study was aimed to evaluate the correlation between 25(OH)D serum concentration and estradiol, testosterone as well as body mass index (BMI) in women with oligomenorrhea. 134 women of reproductive age with oligomenorrhea were eligible for the study. 25-hydroxyvitamin D [25(OH)D], estradiol, testosterone and sex hormone-binding globulin (SHBG) were measured using chemiluminescence immunoassay. Free androgen index (FAI) and body mass index (BMI) were calculated. RESULTS: Critical 25(OH)D deficiency (<10 ng/ml) was found in 13.4% of women, the risk of deficiency (<30 mg/dl) was diagnosed in 69.4%, while sufficient level of VD (>30 mg/ml) in 17.2% of them. Significant negative correlation was detected between 25(OH)D and estradiol serum concentrations (r=-0.2; p=0.049), as well as BMI levels (r=-0.22; p=0.01). However, no significant correlation was found between 25(OH)D and testosterone (r=-017; p=0.055), SHBG (r=0.08; p=0.4) and FAI (r=-0.1; p=0.24). CONCLUSIONS: Thorough assessment of vitamin D deficiency/insufficiency is required among patients with menstrual disorders, especially those overweighed and obese. Early screening and VD supplementation in women with estrogen-dependent disorders may become a part of routine management in order to optimize endocrine health....

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