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19 F electron-nuclear double resonance (ENDOR) spectroscopy is emerging as a method of choice to determine molecular distances in biomolecules in the angstrom to nanometer range. However, line broadening mechanisms in 19 F ENDOR spectra can obscure the detected spin-dipolar coupling that encodes the distance information, thus limiting the resolution and accessible distance range. So far, the origin of these mechanisms has not been understood. Here, we employ a combined approach of rational molecular design, frequency and time domain ENDOR methods as well as quantum mechanical spin dynamics simulations to analyze these mechanisms. We present the first application of Fourier transform ENDOR to remove power broadening and measure T 2n of the 19 F nucleus. We identify nuclear dipolar couplings between the fluorine and protons up to 14 kHz as a major source of spectral broadening. When removing these interactions by H/D exchange, an unprecedented spectral width of 9 kHz was observed suggesting that, generally, the accessible distance range can be extended. In a spin labeled RNA duplex we were able to predict the spectral ENDOR line width, which in turn enabled us to extract a distance distribution. This study represents a first step towards a quantitative determination of distance distributions in biomolecules from 19 F ENDOR.

Riboswitches control gene regulation upon external stimuli such as environmental factors or ligand binding. The fluoride sensing riboswitch from Thermotoga petrophila is a complex regulatory RNA proposed to be involved in resistance to F - cytotoxicity. The details of structure and dynamics underpinning the regulatory mechanism are currently debated. Here we demonstrate that a combination of pulsed electron paramagnetic resonance (ESR/EPR) spectroscopies, detecting distances in the angstrom to nanometre range, can probe distinct regions of conformational flexibility in this riboswitch. PELDOR (pulsed electron-electron double resonance) revealed a similar preorganisation of the sensing domain in three forms, i.e. the free aptamer, the Mg 2+ -bound apo, and the F - -bound holo form. 19 F ENDOR (electron-nuclear double resonance) was used to investigate the active site structure of the F - -bound holo form. Distance distributions without a priori structural information were compared with in silico modelling of spin label conformations based on the crystal structure. While PELDOR, probing the periphery of the RNA fold, revealed conformational flexibility of the RNA backbone, ENDOR indicated low structural heterogeneity at the ligand binding site. Overall, the combination of PELDOR and ENDOR with sub-angstrom precision gave insight into structural organisation and flexibility of a riboswitch, not easily attainable by other biophysical techniques., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Background/Objectives : There are strict demands on body weight and shape in highly trained adolescent female athletes, and they are in the highest risk group for the development of eating disorders. This study aims to compare the behavioural eating patterns between highly trained female adolescent athletes and untrained controls (UCs), and to describe the associations between behavioural eating patterns and different energy homeostasis hormones. Methods : A total of 33 rhythmic gymnasts (RGs), 20 swimmers (SWs), and 20 UCs ( n = 20) that were 14 to 18 years old participated in this investigation. Anthropometric measurements, body composition, training volume, 3-consecutive-day energy intake, and different energy homeostasis hormones were measured. For the evaluation of the individual behavioural eating pattern, an eating disorders assessment scale (EDAS) questionnaire with different subscales was used. Results : The mean EDAS subscale of restrained eating score was significantly higher in the RG group compared to the UC group (17.2 ± 7.4 vs. 11.5 ± 5.8; p < 0.05). The EDAS total score (r = 0.380) and the subscale score of preoccupation with body image and body weight (r = 0.371) were both positively correlated ( p < 0.05) with serum irisin concentrations in the RG group. Conclusions : In conclusion, female rhythmic gymnasts reported a more often restrained eating pattern than untrained controls, and their more disturbed behavioural eating pattern was associated with a higher serum irisin concentration.

Purpose: To describe serum irisin and fibroblast growth factor-21 (FGF-21) concentrations in healthy female adolescents with different training activity patterns and their associations with bone mineral properties and metabolic markers., Methods: A total of 62 adolescent girls aged 14-18 years were recruited: 22 rhythmic gymnasts, 20 swimmers, and 20 untrained controls. Bone mineral characteristics by dual-energy X-ray absorptiometry, daily energy intake by dietary recall, serum irisin, FGF-21, undercarboxylated osteocalcin, and C-terminal telopeptide of type I collagen were measured in all girls., Results: Whole body and lumbar spine areal bone mineral density and lumbar spine bone mineral content were higher in the rhythmic gymnasts group compared with swimmers and untrained controls groups (P < .05). Serum irisin, FGF-21, undercarboxylated osteocalcin, and C-terminal telopeptide of type I collagen levels were not significantly different between the groups. In the rhythmic gymnasts group, serum FGF-21 concentration was positively correlated with lumbar spine areal bone mineral density independently of confounding factors (r = .51; P = .027)., Conclusions: Serum irisin and FGF-21 levels were not different between adolescent eumenorrheic girls with different training activity patterns. FGF-21 was positively associated with lumbar spine areal bone mineral density, which predominantly consists of trabecular bone in adolescent rhythmic gymnasts.

Intracellular leucine aminopeptidases (PepA) are metalloproteases from the family M17. These enzymes catalyze peptide bond cleavage, removing N-terminal residues from peptide and protein substrates, with consequences for protein homeostasis and quality control. While general mechanistic studies using model substrates have been conducted on PepA enzymes from various organisms, specific information about their substrate preferences and promiscuity, choice of metal, activation mechanisms, and the steps that limit steady-state turnover remain unexplored. Here, we dissected the catalytic and chemical mechanisms of Pa PepA: a leucine aminopeptidase from Pseudomonas aeruginosa . Cleavage assays using peptides and small-molecule substrate mimics allowed us to propose a mechanism for catalysis. Steady-state and pre-steady-state kinetics, pH rate profiles, solvent kinetic isotope effects, and biophysical techniques were used to evaluate metal binding and activation. This revealed that metal binding to a tight affinity site is insufficient for enzyme activity; binding to a weaker affinity site is essential for catalysis. Progress curves for peptide hydrolysis and crystal structures of free and inhibitor-bound Pa PepA revealed that Pa PepA cleaves peptide substrates in a processive manner. We propose three distinct modes for activity regulation: tight packing of Pa PepA in a hexameric assembly controls substrate length and reaction processivity; the product leucine acts as an inhibitor, and the high concentration of metal ions required for activation limits catalytic turnover. Our work uncovers catalysis by a metalloaminopeptidase, revealing the intricacies of metal activation and substrate selection. This will pave the way for a deeper understanding of metalloenzymes and processive peptidases/proteases.

Abstract: Remmel, L, Ben-Zaken, S, Meckel, Y, Nemet, D, Eliakim, A, and Jürimäe, J. The genetic basis of decathlon performance: an exploratory study. J Strength Cond Res 37(8): 1660-1666, 2023-Decathlon is a combined track and field competition consisting of 10 different events, most of which are anaerobic-type events. Therefore, it is assumed that an anaerobic genetic predisposition might be prevalent among decathletes. Yet, to the best of our knowledge, the genetic basis of decathlon performance had not been studied. Therefore, the aim of this study was to assess the prevalence genetic polymorphisms associated with power performance (AGT, rs699, Met235Thr T/C), speed (ACTN3, rs1815739 C1747T), aerobic endurance (PPARD, rs2016520 T294C), and lactate clearance (MCT1, rs1049434 A1470T) among decathletes. One hundred thirty-seven male track and field athletes (51 sprinters and jumpers, 59 long distance runners, and 27 decathletes) participated in the study. Genomic DNA was extracted from buccal epithelial cells. Genotypes were determined using the Taqman allelic discrimination assay. Decathletes had a higher prevalence of the ACTN3 RR genotype, which is associated with speed ability, and a lower prevalence of the PPARD CC genotype, which is associated with endurance performance compared with long-distance runners. Decathletes had a higher prevalence of the AGT CC genotype associated with strength performance and a higher prevalence of the MCT1 TT genotype, which is associated with improved lactate transport compared with both sprinters and jumpers and long-distance runners. The results suggest that a favorable genetic polymorphism for strength-related capability might be advantageous for decathletes, whereas a genetic makeup favoring aerobic performance is not necessary., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 National Strength and Conditioning Association.)

Follistatin is a member of the activin-follistatin-inhibin hormonal system and is proposed to affect bone metabolism. However, data regarding the effect of follistatin on bone are relatively scarce and contradictory in humans. The purpose of the current study was to investigate possible associations of serum follistatin concentration with bone mineral characteristics in lean and physically active adolescent girls. Bone mineral density, body composition, resting energy expenditure and different energy homeostasis hormones in serum including follistatin, leptin and insulin were investigated. Significant relationships ( p < 0.05) between serum follistatin (1275.1 ± 263.1 pg/mL) and whole-body (WB) bone mineral content (r = 0.33), WB areal bone mineral density (aBMD) (r = 0.23) and lumbar spine (LS) aBMD (r = 0.29) values were observed. Serum follistatin remained associated with LS aBMD independent of body fat and lean masses (r = 0.21; p < 0.05). However, the follistatin concentration explained only 3% (R 2 × 100; p = 0.049) of the total variance in LS aBMD values. In conclusion, serum follistatin concentrations were associated with bone mineral values in lean adolescent girls with increased physical activity. Follistatin was an independent predictor of lumbar spine areal bone mineral density, which predominantly consists of trabecular bone.

The aim of the study was to examine the effects of supervised cycling sprint interval training (SIT) on serum osteocalcin, lipocalin-2 and sclerostin levels, and bone mineral characteristics among obese adolescent boys. Untrained obese adolescent boys aged 13.4 ± 0.3 were assigned to either a 12-week SIT group (3 sessions/week), or a non-exercising control group who continued with their habitual everyday life. Serum osteocalcin, lipocalin-2 and sclerostin concentrations, and bone mineral values were assessed before and after intervention. After 12-week intervention, where 14 boys in both groups ended the study, there were no significant differences in serum osteokine levels between the groups after 12 weeks, while whole body bone mineral content and lower limb bone mineral density increased in the SIT group ( p < 0.05). Change in body mass index was negatively correlated with the change in osteocalcin (r = -0.57; p = 0.034), and positively correlated with the change in lipocalin-2 levels (r = 0.57; p = 0.035) in the SIT group. Supervised 12-week SIT intervention improved bone mineral characteristics, but did not change osteocalcin, lipocalin-2 or sclerostin levels in adolescent boys with obesity.

Longitudinal bone content data from puberty to adulthood was assessed in 102 healthy males and associations with arterial health in adulthood was analysed. Bone growth in puberty was related to arterial stiffening and final bone mineral content to decreased arterial stiffness. Relationships with arterial stiffness were dependent on the studied bone regions., Introduction: Our aim was to assess the relationships between arterial parameters in adulthood and bone parameters in several locations longitudinally from puberty to 18-years and cross-sectionally at 18-years., Methods: 102 healthy male data from a 7-year follow-up study was used to analyse total body (TB), femoral neck (FN) and lumbar spine (LS) mineral content and density by DXA, carotid intima-media thickness (cIMT) by ultrasound, carotid-femoral pulse wave velocity (cfPWV) and heart rate adjusted augmentation index (AIxHR75) by applanation tonometry., Results: Linear regression analysis revealed negative associations between LS bone mineral density (BMD) and cfPWV [ß=-1.861, CI -3.589, -0.132, p=0.035] which remained significant [ß=-2.679, CI -4.837, -0.522, p=0.016] after adjustment to smoking, lean mass, weight category, pubertal stage, physical fitness, and activity. For AIxHR75 similar results were present [ß=-0.286, CI -0.553, -0.020, p=0.035], but were dependent on confounders. Analysis on pubertal bone growth speed showed independent positive associations to AIxHR75 between Δ FN bone mineral apparent density (BMAD) [ß=672.50, CI 348.07, 996.93, p<0.001] and Δ LS BMAD [ß=700.40, CI 57.384, 1343.423, p=0.033]. Further analysis combining pubertal bone growth and adulthood BMC revealed that the relationships of AIxHR75 with LS BMC and ΔFN BMAD were independent of each other., Conclusion: Trabecular bone regions like lumbar spine and femoral neck, showed stronger relationships with arterial stiffness. Rapid bone growth in puberty is related to arterial stiffening, while final bone mineral content relates to decreased arterial stiffness. These results could indicate that bone metabolism is independently associated with arterial stiffness rather than bone and arteries just having common traits of growth and maturation., (© 2023. International Osteoporosis Foundation and Bone Health and Osteoporosis Foundation.)

Transient insulin resistance seen during puberty is expected to favour body growth, but our results show that increment in insulin resistance even in physiological ranges during puberty might compromise lumbar spine bone mineral density accrual independently of body composition parameters, and therefore adult bone quality might be challenged., Introduction: Insulin resistance (IR) might have a compromising effect on growing bone, and therefore adult bone quality might be challenged. The aim of the present study was to identify whether increases in IR during puberty contribute to bone mineral characteristics in males independently of body composition parameters., Methods: This is a retrospective cohort-based longitudinal observational study. Data from 85 subjects were included. Boys were studied annually during their pubertal years (12 years at baseline) and at follow-up at the age of 18 years. Anthropometry, bone age, fasting blood samples, body composition, total body, and lumbar spine bone mineral characteristics were measured. Insulin resistance was determined by homeostatic model assessment of IR (HOMA-IR). Multiple regression analysis was performed to determine the effect of changes in HOMA-IR during pubertal years as a longitudinal predictor to fixed bone mineral outcome variables at the age of 18 years. All models were adjusted to potential clinically justified confounding variables., Results: After adjustment to baseline bone indices and body composition-related predictors, the pubertal increment in the HOMA-IR was a negative independent predictor of lumbar spine bone mineral areal density (β =  - 0.202, p = 0.005) and lumbar spine bone mineral apparent density (β =  - 0.235, p = 0.005) in 18-year-old males., Conclusions: Pubertal increment in IR has a potential diminishing effect on lumbar spine bone mineral density accrual independently of body composition parameters. Further studies are needed to clarify whether monitoring HOMA-IR during puberty may identify subjects at increased risk of low peak bone mass and possible osteoporosis in the future., (© 2022. International Osteoporosis Foundation and Bone Health and Osteoporosis Foundation.)

Background: This study investigated the effects of supervised short-term sprint interval training (SIT) on circulating irisin, interleukin (IL)-6 and tumour necrosis factor (TNF)-α concentrations, and aerobic capacity and body composition values in healthy older men., Methods: Eleven older men (63±8 years; 178.0±5.5 cm; 82.7±8.6 kg; 22.7±3.7% body fat) underwent SIT (6 repetitions of 30 s all-out cycling bouts with 4 min active recovery after each bout) three days a week for three consecutive weeks. Body composition measured by dual-energy X-ray absorptiometry, aerobic capacity assessed by direct peak oxygen consumption (VO2peak) test and morning fasting blood samples were obtained before and after a 3-week SIT intervention., Results: Nine supervised SIT sessions moderately (effect size [ES] =0.65; P<0.05) increased irisin concentrations (from 135.40±28.73 to 154.20±47.09 ng.mL -1 ) together with moderate decreases (P<0.05) in IL-6 (ES=0.89; from 1.26±0.44 to 0.87±0.44 pg.mL -1 ) and TNF-α (ES=0.64; from 5.10±1.23 to 4.31±1.20 pg.mL -1 ) levels in older men. In addition, increase in VO2peak was significant but small (ES=0.25; P<0.05; from 36.0±7.1 to 37.8±6.7 mL.min. -1 kg -1 ), while no changes (P>0.05) in body composition variables were observed after a short-term SIT period., Conclusions: A 3-week SIT intervention with only nine training sessions increased circulating irisin concentrations, improved inflammatory profile and aerobic capacity without changes in body composition in healthy older men. Accordingly, a short-term SIT programme is a time efficient alternative for traditional aerobic training to improve metabolic health and aerobic capacity in older adults.

The aim of this investigation was to determine the associations of serum irisin and fibroblast growth factor-21 (FGF-21) with the measures of energy homeostasis, training stress and other energy homeostasis hormones in highly trained adolescent rhythmic gymnasts (RG). Thirty-three RG and 20 untrained controls (UC) aged 14−18 years participated in this study. Body composition, resting energy expenditure (REE), peak oxygen consumption, and different energy homeostasis hormones in serum, including irisin, FGF-21, leptin, and resistin, were measured. Irisin and FGF-21 were not significantly different (p > 0.05) between RG and UC groups. In RG, serum irisin was positively associated with REE (r = 0.40; p = 0.021) and leptin (r = 0.60; p = 0.013), while serum FGF-21 was related to body fat mass (r = 0.46; p = 0.007) and leptin (r = 0.45; p = 0.009). Irisin was related to FGF-21, independent of age, body fat, and lean masses (r = 0.36; p = 0.049) in RG. In conclusion, serum irisin concentration was associated with energy expenditure and serum FGF-21 level with energy availability measures in lean adolescent athletes, while no relationships of irisin and FGF-21 with energy status measures were observed in lean nonathletic adolescents.

Purpose: To evaluate the long-term effect of body composition, physical activity, and cardiorespiratory fitness (CRF) from puberty on arterial health in late adolescent males., Methods: The cumulative burden of physical activity (measured with accelerometer), CRF (VO2peak0.82), and body composition (body mass index, fat mass, and fat percentage) from puberty to late adolescence (sum of 4 time points from 12 to 18 y) was assessed in 102 males. Additional analysis on the first (T1) and last (T4) time points was performed. Intima-media thickness (IMT), carotid-femoral pulse wave velocity, and augmentation index adjusted to heart rate of 75 beats per minute (bpm) as dependent variables were measured at T4 and analyzed in multivariable regression models adjusted for known risk factors including maturation, blood pressure, and smoking habits., Results: T1 and cumulative body composition measures were independently associated with IMT, while cumulative (β = -0.011, P = .036) and T4 (β = -0.0.031, P = .001) CRF revealed independent associations with IMT. Individuals with moderate to vigorous physical activity >60 minutes per day at T1 showed relationship (β = -1.091, P = .026) with IMT independently of late adolescent physical activity. No significant relationship was present for arterial function., Conclusion: Arterial structure in adolescent males is associated with physical activity at 12 years while relationship with CRF can be seen in late adolescence and cumulatively from puberty to late adolescence.

This study investigated the effect of supervised sprint interval training (SIT) on different cardiometabolic risk factors and adipokines in adolescent boys with obesity. Thirty-seven boys were allocated to either a SIT group (13.1 ± 0.3 years; body mass index [BMI]: 30.3 ± 0.9 kg·m -2 ) or a control group (CONT) (13.7 ± 0.4 years; BMI: 32.6 ± 1.6 kg·m -2 ). The SIT group performed 4-6 × 30 s all-out cycling sprints, interspersed with 4 min rest, for 3 sessions/week, during a 12-week period, while the non-exercising CONT group maintained a habitual lifestyle. Anthropometric measurements, triglycerides, fasting insulin and glucose, total cholesterol (TC), high- (HDLc) and low-density (LDLc) cholesterol, leptin and adiponectin in blood, cardiorespiratory fitness (CRF), and a metabolic syndrome severity risk score (MSSS) were calculated before and after the 12-week period. Compared to baseline values, a significant reduction in MSSS was seen in the SIT group after intervention. LDLc showed favorable changes in SIT compared to CONT (-0.06 ± 0.1 vs. 0.19 ± 0.01 mmol·L -1 ; p = 0.025). Additionally, CRF increased in the SIT group compared to the CONT group (5.2 ± 1.1 vs. -2.1 ± 1.1 mL·min -1 ·kg -1 , p < 0.001). Moreover, a 12-week all-out SIT training effectively improves cardiometabolic health in adolescent boys with obesity.

This study examined the effect of a supervised 12-week sprint interval training (SIT) on cardiorespiratory fitness (CRF) and body composition in adolescent boys with obesity. Twenty-eight adolescents with obesity were allocated to either an intervention group (SIT) (13.1 ± 0.3 yrs; body mass index [BMI]: 30.3 ± 0.9 kg.m -2 ) or a control group (CONT) (13.7 ± 0.4 yrs; BMI: 32.6 ± 1.6 kg.m -2 ). The SIT group performed 4-6 × 30s "all-out" cycling bouts, interspersed with 4 min of recovery 3 days a week for 12 weeks. CRF was measured by direct peak oxygen consumption (VO 2 peak) defined as VO 2 peak per kg of body mass (mL.min -1 kg -1 ) or by VO 2 peak per kg of lean body mass (mL.min -1 LBM -1 ) and body composition was assessed by dual-energy X-ray absorptiometry. SIT intervention led to a significant and large between-group difference in VO 2 peak (p = 0.004; η 2  = 0.29). Although SIT group had a significant reduction in body fat percentage (BF%) (from 41.1 ± 1.3% to 39.2 ± 1.5%; p = 0.006), there were no between-group differences in the change of the pre- and post-measures in BF% (p = 0.067). In conclusion, 12-week SIT is effective in increasing CRF and decreasing BF% in adolescent boys with obesity.

Objective: Decathlon is a combined track and field competition, consisting of ten, mainly anaerobic events. Insulin-like growth factor-I (IGF1) axis plays a pivotal role in athletes' structural and functional muscle adaptation to exercise training, and in their competitive performance. Based on the great demand for speed physiological characteristics among decathlon athletes, the aim of this study was to assess the prevalence of IGF genetic polymorphisms among decathletes, to present an optimal genetic profile for enhancing performance., Methods: The participants included 151 male athletes and 75 male non-athletic controls from Israel and Estonia. Athletes were divided into four groups, according to the field of expertise: (a) 40 sprinters and long jumpers; (b) 40 middle distance runners; (c) 44 Weightlifters; and (d) 27 decathletes. Genomic DNA was extracted from the participants' buccal epithelial cells using standard protocol and then analyzed for IGF1 axis related genetic polymorphism using the allelic discrimination assay., Results: A significantly higher prevalence of the IGF1 rs35767 TT genotype was found among decathletes compared to the other athletes, as well as a lower prevalence of the IGF1 rs7136446 GG genotype, a higher prevalence of the IGF1R rs1464430 AA genotype, and a higher prevalence of the IGF2 rs680 GG genotype. Moreover, among the decathletes, carriers of the IGF1 rs7136446 GG genotype achieved higher decathlon scores compared to A-allele carriers., Conclusions: The findings of this study suggest a potential beneficial role for some IGF-axis polymorphisms (mainly the IGF1 1245 TT and the IGF2 GG) among decathletes, both of which are associated with improved speed performance., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Introduction: Inconsistent associations of leptin and adiponectin with bone mineral characteristics in puberty and adolescence have been reported. We aimed to examine the associations between leptin to adiponectin ratio (LAR) in puberty and bone mineral characteristics at the age of 18 years in healthy males., Materials and Methods: 88 white Caucasian boys were investigated at T1 (mean age 12.1 years), T2 (14.0 years) and T3 (18.0 years). Serum leptin and adiponectin were measured and LAR was calculated at T1, T2 and T3, bone mineral density (BMD) and bone mineral apparent density (BMAD) for total body and lumbar spine (LS) at T1 and T3. Spearman correlation coefficient and partial correlation analyses were used to describe the associations between mean pubertal LAR and BMD at T3., Results: Mean pubertal LAR was negatively correlated with both LS BMD (r = -0.23; P < 0.05) and LS BMAD at T3 (r = -0.33; P < 0.05). These associations remained significant also in partial correlation analysis after controlling for total body fat percentage, total testosterone, HOMA-IR and physical activity at T1 (r = -0.31; P < 0.05 and r = -0.41; P < 0.05 respectively)., Conclusion: LAR in puberty is negatively associated with lumbar spine BMD and lumbar spine BMAD at the age of 18 years., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)

Rhythmic gymnasts (RGs) are more likely to be dissatisfied with their body mass and shape compared to untrained controls (UCs). However, due to the lack of information, the aim of this study was to investigate the associations of body image perception (BIP) with body composition, daily energy consumption and different blood biochemical markers in adolescent RGs compared to UCs. Thirty-three highly trained RG girls and 20 UC girls aged 14-18 years participated in this cross-sectional study. Height, body mass, body composition, energy intake, resting energy expenditure, training volume and different blood biochemical markers were measured. The body attitude test (BAT) was used to evaluate the BIP of the participants. There were no differences in the total BAT scores between the groups. In RGs, the BAT score correlated positively with the serum resistin level (r = 0.35; p = 0.047). A stepwise multiple regression analysis showed that 40.8% of the variability in the BAT score was determined by resistin and BMI. The association of BIP with resistin values was observed only in RGs. In conclusion, our findings add to the increasing evidence that resistin may be a link between BIP and body composition, most likely through fat mass, in adolescent female RGs.

The aim of this investigation was to determine the relationships of areal bone mineral density (aBMD) and content (BMC) with body composition, blood hormone and training load variables in adolescent female athletes with different loading patterns. The participants were 73 healthy adolescent females (14-18 years), who were divided into three groups: rhythmic gymnasts (RG; n = 33), swimmers (SW; n = 20) and untrained controls (UC; n = 20). Bone mineral and body compositional variables were measured by dual-energy X-ray absorptiometry, and insulin-like growth factor-1 (IGF-1), estradiol and leptin were analyzed from blood samples. In addition, aerobic performance was assessed by a peak oxygen consumption test. No differences ( p > 0.05) in weekly training volume were observed between rhythmic gymnasts (17.6 ± 5.3 h/week) and swimmers (16.1 ± 6.9 h/week). Measured areal bone mineral density and bone mineral content values were higher in rhythmic gymnasts compared with other groups ( p < 0.05), while no differences ( p > 0.05) in measured bone mineral values were seen between swimmers and untrained control groups. Multiple regression models indicated that IGF-1 alone explained 14% of the total variance (R 2 × 100) in lumbar spine aBMD, while appendicular muscle mass and training volume together explained 37% of the total variance in femoral neck BMC in the rhythmic gymnast group only. In swimmers, age at menarche, estradiol and appendicular muscle mass together explained 68% of the total variance in lumbar spine BMC, while appendicular muscle mass was the only predictor and explained 19 to 53% of the total variance in measured bone mineral values in untrained controls. In conclusion, adolescent rhythmic gymnasts with specific weight-bearing athletic activity present higher areal bone mineral values in comparison with swimmers and untrained controls. Specific training volume together with appendicular muscle mass influenced cortical bone development at the femoral neck site of the skeleton in rhythmic gymnasts, while hormonal values influenced trabecular bone development at the lumbar spine site in both athletic groups with different loading patterns.

The purpose of this investigation was to study whether prolonged competitive rhythmic gymnastics training influenced bone mineral accrual in premenarcheal girls. Eighty-nine girls (45 rhythmic gymnasts [RG] and 44 untrained controls [UC]) between 7 and 9 years of age were recruited and measured annually for four years (not all participants were measured at every occasion). Dual energy x-ray absorptiometry was used to assess the development of whole body (WB), femoral neck (FN) and lumbar spine (LS) bone mineral content (BMC). In addition, body composition, blood adipokine and jumping performance characteristics were obtained. For longitudinal analyses, hierarchical mixed-effects models were constructed to predict differences in the development of WB, FN and LS BMC between RG and UC groups, while accounting for differences in body composition, blood adipokine and jumping performance values. It appeared that from 8 years of age, RG had lower (p < 0.05) fat mass and leptin values, and higher (p < 0.05) jumping performance measures in comparison with UC girls. Hierarchical mixed-effects models demonstrated that RG had 71.9 ± 12.0, 0.23 ± 0.11 and 1.39 ± 0.42 g more (p < 0.05) WB, FN and LS BMC, respectively, in comparison with UC girls. In addition, WB, FN and LS BMC increased more (p < 0.05) between 7 to 12 years of age in RG girls in comparison with UC. In conclusion, these findings suggest that the prolonged exposure to competitive rhythmic gymnastics trainings in premenarcheal girls is associated with greater bone mineral accrual despite lower body fat mass and leptin values., (© Journal of Sports Science and Medicine.)

There is a lack of studies investigating whether objectively measured physical activity (PA) and cardiorespiratory fitness (CRF) in puberty is associated with healthier body composition in late adolescence. The study sample included 71 boys, who were measured at puberty (mean age of 12.1 years) and again at late adolescence (mean age of 18.1 years). Physical activity was measured by accelerometry, and total PA, moderate-to-vigorous PA (MVPA), and sedentary time (SED) were calculated, while CRF was assessed by a peak oxygen consumption test. Body composition was measured by dual-energy X-ray absorptiometry, and body fat percentage (%BF), fat mass index (FMI), trunk fat mass index (TFMI), and fat-free mass index (FFMI) were calculated. Body mass index (BMI) and SED time increased, while MVPA, total PA, and CRF decreased from puberty to late adolescence. A relatively high degree of tracking for BMI and CRF, and a low tracking for PA from puberty to late adolescence was observed. Only the CRF value at puberty negatively predicted adolescent BF% (β = -0.221; p = 0.015), FMI (β = -0.212; p = 0.006), and TFMI (β = -0.189; p = 0.015) values. Adolescents whose CRF was above the median at puberty had lower BMI, BF%, FMI, and TFMI in comparison to those whose CRF was below the median at puberty. In conclusion, measured CRF and PA values decreased from puberty to late adolescence. Pubertal CRF predicted body fatness indices six years later in healthy adolescents.

Objectives: Sclerostin is an important regulator of bone mass involving the Wnt/β-catenin signalling pathway. Relatively few studies have investigated the relationships of circulating sclerostin levels with adiposity-related and muscle-related biochemical factors in individuals with increased energy metabolism. The aim of this study was to investigate the associations of circulating sclerostin with adipokines, myokines, osteokines and body composition values in lean adolescent females with increased physical activity., Methods: A total of 73 adolescent females who were physically active and aged 14-18 years old participated in the study. Sclerostin, leptin, resistin, tumour necrosis factor (TNF)-α, interleukin (IL)-6, irisin, osteocalcin, C-terminal telopeptide of type I collagen (CTx), insulin-like growth factor (IGF)-1 and insulin were obtained from fasting blood samples. Body composition was measured by dual-energy X-ray absorptiometry (DXA) and analyzed for body fat mass, lean body mass, bone mineral content and muscle mass., Results: Serum sclerostin (117.9 ± 60.3 pg/mL) was correlated with age, age at menarche, body fat, muscle mass, training activity, leptin, TNF-α, irisin, osteocalcin, CTx and IGF-1. Multivariate linear regression analysis demonstrated that fat mass ( β = 0.434; p = 0.001), leptin ( β = -0.308; p = 0.015), irisin ( β = 0.227; p = 0.024) and CTx ( β = 0.290; p = 0.031) were the most important predictors of serum sclerostin concentration., Conclusions: Bone-derived sclerostin is associated with specific adipokine, myokine and osteokine values in lean adolescent females with increased physical activity. These results suggest that the interactions between bone, adipose and muscle tissues could also be associated with circulating sclerostin concentrations., (© 2021 Walter de Gruyter GmbH, Berlin/Boston.)

Introduction: The specific aims of the study were to compare possible differences in sclerostin and preadipocyte factor-1 (Pref-1) between rhythmic gymnasts (RG), swimmers (SW) and untrained controls (UC), and to investigate the relationships of sclerostin and Pref-1 with bone mineral characteristics in studied groups., Materials and Methods: This study included 62 eumenorrheic adolescents (RG = 22; SW = 20; UC = 20). Bone mineral and body composition characteristics were measured by dual-energy X-ray absorptiometry, and sclerostin, Pref-1, osteocalcin and C-terminal telopeptide of type I collagen (CTx) were measured., Results: Sclerostin was higher (P = 0.001) in RG (129.35 ± 51.01 pg/ml; by 74%) and SW (118.05 ± 40.05 pg/ml; by 59%) in comparison with UC (74.32 ± 45.41 pg/ml), while no differences (P = 0.896) were seen in Pref-1 (RG: 1.42 ± 0.16 ng/ml; SW: 1.41 ± 0.20 ng/ml; UC: 1.39 ± 0.26 ng/ml) between groups. Osteocalcin (RG: 7.74 ± 4.09 ng/ml; SW: 8.05 ± 4.18 ng/ml; UC: 7.04 ± 3.92 ng/ml; P = 0.843) and CTx (RG: 0.73 ± 0.22 ng/ml; SW: 0.64 ± 0.16 ng/ml; UC: 0.62 ± 0.20 ng/ml; P = 0.173) were not different between groups. Sclerostin correlated (P < 0.05) with whole-body bone mineral content (r = 0.61) and lumbar spine (LS) areal bone mineral density (aBMD) (r = 0.43) in RG, and femoral neck aBMD (r = 0.45) in UC. No correlation was found between sclerostin and bone mineral values in SW, and Pref-1 was not correlated with any bone mineral characteristics in studied groups. Sclerostin was the independent variable that explained 14% of the total variance (R 2  × 100) in LS aBMD value only in RG., Conclusions: Adolescent athletes have higher sclerostin compared to UC. Sclerostin was correlated with bone mineral values and predicted areal bone mineral density in RG.

Proteins encoded by small open reading frames (sORFs) have a widespread occurrence in diverse microorganisms and can be of high functional importance. However, due to annotation biases and their technically challenging direct detection, these small proteins have been overlooked for a long time and were only recently rediscovered. The currently rapidly growing number of such proteins requires efficient methods to investigate their structure-function relationship. Herein, a method is presented for fast determination of the conformational properties of small proteins. Their small size makes them perfectly amenable for solution-state NMR spectroscopy. NMR spectroscopy can provide detailed information about their conformational states (folded, partially folded, and unstructured). In the context of the priority program on small proteins funded by the German research foundation (SPP2002), 27 small proteins from 9 different bacterial and archaeal organisms have been investigated. It is found that most of these small proteins are unstructured or partially folded. Bioinformatics tools predict that some of these unstructured proteins can potentially fold upon complex formation. A protocol for fast NMR spectroscopy structure elucidation is described for the small proteins that adopt a persistently folded structure by implementation of new NMR technologies, including automated resonance assignment and nonuniform sampling in combination with targeted acquisition., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

The aim was to investigate the possible association of dietary calcium intake with adiposity, insulin resistance, and adipocytokine values in adolescent boys. In this cross-sectional study, participants were 123 adolescent boys aged 13-15 years, who were divided into tertiles according to their dietary calcium intake. Dietary calcium intake was assessed using three 24 h dietary recalls. In addition, energy intake, body composition, physical activity (PA), and blood biochemical values were also measured. Mean body fat%, fat mass (FM), trunk FM, trunk fat%, and leptin differed between high and low tertiles of calcium intake after adjustment for age, pubertal stage, and PA. For the entire cohort, mean calcium intake was 786 ± 380 mg/day and was related to body mass index (BMI), FM, and trunk fat% but not to insulin resistance or adipocytokine values after adjusting for possible confounders. In addition, only 15.4% of the participants obtained or exceeded their mean dietary calcium intake requirements. These subjects who met their dietary calcium intake had significantly lower body fat% in comparison with subjects not meeting their dietary calcium intake. Odds ratio of being in the highest tertile of FM, trunk FM, and trunk fat% was 3.2-4.4 (95% confidence interval 1.19-12.47; p < 0.05) times higher for boys in low calcium intake tertile, compared to those boys in high calcium intake tertile. In conclusion, dietary calcium intake is inversely associated with total body and abdominal adiposity values in a specific group of healthy male adolescents with different body mass values.

Background and objectives: Studies indicate that genetic and lifestyle factors influence optimal bone development. Adaptations in bone mineral characteristics related to physical activity (PA) are most often observed in pre- and peri-puberty. Longitudinal associations between bone mineral accrual and objectively measured PA in puberty are poorly understood. The present study aims to investigate whether pubertal PA at different intensities is related to bone mineral characteristics in individuals at 18 years of age. Materials and Methods: Anthropometrics, pubertal stage, bone age and PA by accelerometer were measured in 88 boys at the mean age of 12.1 (T1), 13.1 (T2), 14.0 (T3) and 18.0 years (T4). Different bone mineral parameters were measured by dual-energy X-ray at T4. Stepwise multiple regression analysis was performed to determine the effect of bone age, body mass and PA characteristics on measured bone mineral parameters at 18 years of age. Results: Total PA in puberty together with mean pubertal body mass predicted 35.5% of total body (TB) bone mineral density (BMD), 43.0% of TB less head (LH) bone mineral content (BMC) and 48.1% of BMC/height in individuals at 18 years of age. Vigorous PA and body mass in puberty predicted 43.2% of femoral neck (FN) BMD; bone age at T1, vigorous PA and body mass in puberty predicted 47.3% of FN BMC at 18 years of age. No associations between pubertal PA levels and lumbar spine bone mineral characteristics in individuals at 18 years of age were found. Conclusions: Physical activity in puberty has a significant impact on bone mineral characteristics in individuals at 18 years of age, with total PA being a significant predictor of TB BMD and TB LH BMC as well as BMC/height, whereas vigorous PA is a significant predictor of FN BMD and FN BMC., Competing Interests: The authors declare no conflict of interest.

Purpose: Vigorous physical activity (VPA) has been proven to promote osteogenesis in adolescents; however the specifics of the optimal pattern of frequency and duration of VPA are unknown. The main goal of the present study was to analyze the associations of different length of VPA bouts with bone health., Methods: 180 healthy male adolescents (11-13 years) had their bone mineral content and density assessed by dual-energy X-ray absorptiometry scans at the whole body, femoral neck (FN) and lumbar spine and their physical activity measured by an accelerometer during one week., Results: VPA was the intensity with the strongest associations with bone mineral parameters especially at the FN. Subjects whose longest VPA bout was 5 min or above had higher FN bone mineral density (BMD) than those who did not complete any 5-min bout and these differences were greater with participants who reached 15 consecutive minutes of VPA (>15': 0.977 ± 0.020 g/cm2; 5'-15': 0.907 ± 0.009 g/cm2; <5': 0.876 ± 0.009 g/cm2; all p < 0.05). When comparing the relevance of VPA bouts and volume of physical activity, the group with low volume and having a VPA bout had better FN BMD compared to the group with high volume but no VPA bout. Additionally, the group with both high volume and VPA bout showed better FN BMD than the rest of the groups., Conclusions: VPA may be the most effective activity intensity to improve bone mineral density and content of adolescent boys, with greater benefits if VPA periods either long or frequent., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Cross-sectional studies have associated serum testosterone with bone mineral density (BMD). However, there is a shortage of prospective longitudinal studies in this domain, leaving it unclear whether changes in testosterone level precede changes in BMD., Objectives: To examine the association between serum testosterone concentration at the age of 12 years and a subsequent increase in BMD by the age of 18 years., Methods: Eighty-eight boys with a mean age of 12.1 ± 0.7 (time point 1 [T1]) and 18.0 ± 0.7 (T2) were investigated. For both time points, serum testosterone was measured from venous blood samples. Total body (TB) and lumbar spine (LS) BMD and bone mineral apparent density (BMAD) were measured. As different brands of DEXA machines were used at T1 and T2, we calculated SD scores (SDS) from samples at T1 and T2 and their change (Δ). As covariates, bone age at T1 and physical activity (PA) by accelerometer at T1 and T2 were measured., Results: Serum testosterone at T1 was positively correlated with TB BMD at T2 (r = 0.28; p < 0.01), Δ TB BMAD SDS (r = 0.47; p < 0.0001) and Δ LS BMAD SDS (r = 0.23; p < 0.05). When additionally controlling for bone age and total PA at T1, the correlation between testosterone at T1 and Δ TB BMAD SDS remained significant (r = 0.32; p < 0.05)., Conclusions: Serum testosterone concentration at the age of 12 years is associated with a subsequent increase in TB BMAD by the age of 18 years. This supports the inference that testosterone levels in early puberty may influence subsequent bone mineral accrual., (© 2019 S. Karger AG, Basel.)

Purpose: To investigate the differences in the pattern of changes in serum inflammatory cytokines measured annually over a 24-month period, between less active and more active overweight boys., Participants/methods: In total, 25 pubertal overweight boys were divided by their moderate to vigorous physical activity (MVPA) levels into 2 groups: less active group (LAG; n = 10; MVPA < 60 min/d) and more active group (MAG; n = 15; MVPA > 60 min/d). Physical activity was measured by 7-day accelerometry. Serum concentration of 13 inflammatory cytokines [interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, IL-1α, IL-1β, vascular endothelial growth factor, interferon-γ, tumor necrosis factor-α, monocyte chemotactic protein-1, epidermal growth factor, and C-reactive protein] was measured at baseline (T0), after 12 months (T1), and after 24 months (T2) from fasting blood samples., Results: Serum IL-6 level was significantly higher [LAG: 1.27 (0.86, 1.98) pg/mL; MAG: 0.80 (0.52, 0.84) pg/mL] at T0 and IL-8 level [LAG: 10.26 (8.80, 11.64) pg/mL; MAG: 7.42 (6.10, 9.54) pg/mL] at T2 in LAG compared with MAG. The changes over the study period varied between different inflammatory markers. None of the slopes of any measured markers were statistically different between the LAG and MAG, although the slopes of interferon-γ and IL-10 tended to be different between the groups., Conclusions: The pattern of changes over the study period varied between different inflammatory markers, but these changes were not different between the MVPA groups. More longitudinal studies are needed to investigate whether IL-6, IL-8, IL-10, and interferon-γ would be the choice of inflammatory markers to study the associations between obesity and physical activity in future.

Purpose: Associations between osteocalcin (OCN), an osteoblast-specific hormone, and different markers of energy metabolism and insulin resistance have been reported in adults, but few studies have investigated this in children. The aim of the current study was to investigate serum OCN levels during pubertal development in normal weight (NW) and overweight (OW) boys, and to evaluate possible associations of OCN with body composition, testosterone, insulin resistance and adipocytokine values during puberty., Methods: Ninety 11- to 12-year-old boys were investigated at 12-month intervals over the next 2years. Boys were divided by their BMI into NW (n=60) and OW (n=30) groups. Serum OCN, testosterone, leptin, adiponectin, insulin, HOMA-IR score, and body composition were measured., Results: Pubertal development over the 2-year period was similar in both groups. Serum OCN was not different at the beginning of the study and increased similarly in both groups. However, at the end of the study, NW had higher OCN than OW (142.9±5.2 vs. 124.0±7.4ng/ml; p<0.05). OW had higher leptin, insulin and HOMA-IR compared to NW, and these differences remained significant through the 2-year period. Testosterone, insulin and HOMA-IR increased through the study period in both groups. In multiple regression analyses increment in OCN was associated with the increase in testosterone in NW (p<0.001) and OW (p=0.049) boys. Increment in OCN was also associated with the increase in insulin (p=0.019) and HOMA-IR (p=0.012) over the 2-year period in NW boys., Conclusion: Serum OCN concentration increases in puberty and the increment is positively associated with the rise in testosterone level in both NW and OW boys. The positive association between the rise in OCN and insulin in NW boys would suggest that OCN may have a role in the development of insulin resistance., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The aim of this study was to investigate the differences in associations of serum acylated and des-acylated ghrelin, peptide YY (PYY) and leptin levels with physical activity (PA) and cardiorespiratory fitness (CReF) in adolescent boys (mean age of 14.0 years) with overweight (OWB; n=55) and with normal weight (NWB; n=154)., Methods: Total PA was measured by 7-day accelerometry (counts/min) and CReF by peak oxygen consumption (VO 2 peak/kg)., Results: No differences were found in serum PYY, acylated ghrelin or des-acyl ghrelin levels, whereas mean leptin (11.6±10.6 vs. 2.0±2.7 ng/ml; p<0.05) and insulin (18.1±8.7 vs. 11.0±6.2 mU/l; p<0.05) levels were significantly higher in OWB compared to NWB. Mean CReF was significantly lower in OWB compared to NWB (39.7±8.7 vs. 50.5±6.8 ml/min/kg; p<0.05). Leptin was negatively correlated with CReF in both groups (r=-0.43; p<0.05), des-acylated ghrelin with CReF only in OWB (r =-0.36; p<0.05). In OWB leptin was negatively correlated with total PA (r=-0.32; p<0.05) and positively with sedentary time of PA (r=0.35; p<0.05). In NWB 28.1% of the variability of CReF was determined by leptin and insulin resistance index (HOMA-IR), whereas in OWB 71.9% was determined by trunk FM and BMI., Conclusions: Leptin concentration was inversely associated with CReF in adolescent boys independently of BMI in both groups, while des-acylated ghrelin was associated with CReF only in OWB. Low PA in OWB was associated with high serum leptin level.

The aim of this 3-year prospective study was to examine changes in bone mineral characteristics during pubertal maturation in boys with different BMI values at the beginning of puberty and with different BMI increments during puberty. 26 boys with overweight and obesity (OWB) and 29 normal weight boys (NWB) were studied yearly for 3 years from the age of 11 years to measure the changes in different bone mineral characteristics. The OWB group was further divided into two subgroups according to extensive or non-extensive BMI increment during 3-year period. OWB had higher (P < 0.01) baseline total body (TB) bone mineral density (BMD), TB bone mineral content (BMC), TB BMC for height, lumbar spine (LS) BMD, and LS BMC compared to NWB. Throughout the study period, OWB gained more TB BMD (P = 0.0001), TB BMC (P = 0.0048), TB BMC for height (P = 0.0124), LS BMD (P = 0.0029), and LS BMC (P = 0.0022) compared to NWB. Also during the study period, TB BMD (P = 0.0065), TB BMC (P = 0.0141), TB BMC for height (P = 0.0199), LS BMD (P = 0.0066), LS apparent volumetric BMD (BMAD) (P = 0.0075), and LS BMC (P = 0.017) increased significantly less in those OWB whose BMI increased more extensively. Extensive BMI gain is associated with lower increments in bone mineral characteristics in boys with overweight and obesity. Unfavorable increment in total body fat mass and percentage during pubertal years could be one reason for that.

Various inflammation parameters are increased with childhood obesity, but few comparable data are found in lean growing athletes. This study aims to characterize differences in 12 simultaneously measured inflammatory parameters between pubertal rhythmic gymnasts (RG) and untrained controls (UC), and to examine the relationship between body composition and inflammatory markers. Sixty 10-12-year-old girls were divided into RG (n = 30) and UC (n = 30). Fat mass (FM) and fat free mass (FFM) were measured by dual-energy X-ray absorptiometry. Leptin and 12 inflammatory parameters (interleukin [IL]-2, IL-4, IL-6, IL-8, IL-10, vascular endothelial growth factor, interferon-gamma [IFN-γ], tumor necrosis factor-alpha, IL-1α, IL-1β, monocyte chemotactic protein-1 and epidermal growth factor) were measured from fasting blood samples. No differences were seen in 12 inflammatory markers between studied groups. As expected, leptin (RG: 2.4 ± 1.1; UC: 7.6 ± 4.2 ng ml -1 ) and FM (RG: 7.3 ± 2.3; UC: 11.8 ± 5.1 kg) were lower (p < .05) in RG compared to UC. In the whole group of lean pubertal girls, 69.0% of the variability in body FM was determined by leptin, and 11.2% of the variability in body FFM was explained by IFN-γ. In conclusion, measured 12 inflammatory biomarkers were not different between RG and UC, despite lower leptin and FM in RG. In lean pubertal girls, IFN-γ was independently associated with FFM, and leptin with FM.

Objective: Serum inflammatory markers could help to identify those boys with overweight (OWB) who gain weight more extensively during puberty. This study aimed to examine the longitudinal changes in different serum inflammatory markers through puberty in boys with different BMI values and increments., Methods: Twenty-six OWB and 29 normal-weight boys (NWB) were followed yearly for 3 years to measure changes in BMI and serum concentrations of 12 inflammatory markers., Results: OWB had higher (P < 0.033) baseline interleukin (IL)-6, IL-8, interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), and IL-1α concentrations in comparison with NWB. Over the 3-year period, IFN-γ (P = 0.0001) and TNF-α (P = 0.0042) decreased more in OWB compared to NWB. Serum IL-8, monocyte chemoattractant protein (MCP)-1, and leptin increased further in those OWB who gained BMI more extensively through puberty compared to OWB who gained weight at slower rates (P < 0.033)., Conclusions: Serum IFN-γ and TNF-α levels decreased more during pubertal years in OWB compared to NWB, indicating that pubertal maturation itself may have a favorable impact on the inflammation of obesity. Serum IL-8, MCP-1, and leptin could help to identify OWB who gain BMI more extensively during pubertal years., (© 2017 The Obesity Society.)

Background/aims: The role of ghrelin and peptide YY (PYY) in bone mineralization is not fully known. The aim of this study was to determine whether acylated and des-acyl ghrelin and PYY in addition to leptin are related to bone mineral density (BMD) in adolescent overweight boys (OWB) and normal-weight boys (NWB)., Participants and Methods: Fifty- five OWB (BMI >85th percentile) and 154 NWB (BMI <85th percentile) aged 12-16 years participated in this study. Fasting serum acylated and des-acyl ghrelin, PYY, leptin, testosterone levels, total body (TB) and lumbar spine (LS) bone mineral content (BMC), and BMD were measured. TB BMC for height and TB and LS bone mineral apparent density (BMAD) were calculated., Results: No differences were seen in acylated and des-acyl ghrelin or PYY levels, while the leptin levels were significantly higher in the OWB compared to the NWB. In the OWB, TB BMAD was positively correlated with acylated ghrelin and leptin, and TB BMC for height was positively correlated with PYY. In the OWB, the variability of TB BMD was determined by TB fat-free mass and des-acyl ghrelin, whereas the variability of TB BMAD was determined by leptin., Conclusions: Des-acyl ghrelin and PYY are involved in the bone mineralization process in puberty, and the impact can vary between normal and overweight subjects., (© 2015 S. Karger AG, Basel.)