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BMC Pediatrics Jun 2013The objective of this study was to determine body fat percentiles of adolescents in the city of São Paulo, Brazil, according to gender, age, and sexual maturation.
BACKGROUND
The objective of this study was to determine body fat percentiles of adolescents in the city of São Paulo, Brazil, according to gender, age, and sexual maturation.
METHODS
This study involved 4,690 adolescents aged 10-15 years across 31 schools in the city of São Paulo. Sexual maturation was assessed in terms of Tanner stage. The body fat percentage was calculated using skinfold thickness. Percentile curves were calculated using the LMS (curve, mean, and coefficient of variation) method.
RESULTS
The mean body fat percentages were lower in boys aged 10-12 and 13-15 years than in girls. Body fat percentages decreased progressively with sexual maturation in boys, but increased in girls. The 85th, 95th, and 97th percentiles represent the cutoff points for moderately elevated, elevated, and very elevated body fat percentages, respectively, in pre-pubescent boys (85th, 95th, and 97th percentiles: 32.54, 95 41.04, and 97, respectively) and pubescent boys (31.09, 36.30, and 44.33, respectively). These cutoff points were lower in pre-pubescent girls (29.52, 35.01, and 41.82, respectively) and in the 97th percentile in pubescent girls (31.55, 36.20, and 41.86, respectively).
CONCLUSION
To our knowledge, these are the first body fat percentages cutoff points according to sexual maturation for adolescents aged 10-15 years in Brazil. Our results provide a significant contribution to the assessment of body composition in this population.
Topics: Adipose Tissue; Adolescent; Age Factors; Brazil; Child; Cross-Sectional Studies; Female; Humans; Male; Obesity; Risk Factors; Sex Factors; Sexual Maturation; Skinfold Thickness; Surveys and Questionnaires
PubMed: 23777578
DOI: 10.1186/1471-2431-13-96 -
BMC Genomics Oct 2023Puberty marks the end of childhood and achieve sexual maturation and fertility. The role of hypothalamic proteins in regulating puberty onset is unclear. We performed a...
BACKGROUND
Puberty marks the end of childhood and achieve sexual maturation and fertility. The role of hypothalamic proteins in regulating puberty onset is unclear. We performed a comprehensive differential proteomics and phosphoproteomics analysis in prepubertal and pubertal goats to determine the roles of hypothalamic proteins and phosphoproteins during the onset of puberty.
RESULTS
We used peptide and posttranslational modifications peptide quantification and statistical analyses, and identified 69 differentially expressed proteins from 5,057 proteins and 576 differentially expressed phosphopeptides from 1574 phosphorylated proteins. Combined proteomic and phosphoproteomics, 759 correlated proteins were identified, of which 5 were differentially expressed only at the protein level, and 201 were only differentially expressed at the phosphoprotein level. Pathway enrichment analyses revealed that the majority of correlated proteins were associated with glycolysis/gluconeogenesis, Fc gamma R-mediated phagocytosis, focal adhesion, GABAergic synapse, and Rap1 signaling pathway. These pathways are related to cell proliferation, neurocyte migration, and promoting the release of gonadotropin-releasing hormone in the hypothalamus. CTNNB1 occupied important locations in the protein-protein interaction network and is involved in focal adhesion.
CONCLUSION
The results demonstrate that the proteins differentially expression only at the protein level or only differentially expressed at the phosphoprotein level and their related signalling pathways are crucial in regulating puberty in goats. These differentially expressed proteins and phosphorylated proteins may constitute the proteomic backgrounds between the two different stages.
Topics: Animals; Female; Humans; Proteomics; Goats; Hypothalamus; Puberty; Sexual Maturation; Gonadotropin-Releasing Hormone; Phosphoproteins
PubMed: 37853328
DOI: 10.1186/s12864-023-09705-7 -
Proceedings. Biological Sciences May 2022Epigenetic inheritance can result in plastic responses to changing environments being faithfully transmitted to offspring. However, it remains unclear how epigenetic...
Epigenetic inheritance can result in plastic responses to changing environments being faithfully transmitted to offspring. However, it remains unclear how epigenetic mechanisms such as DNA methylation can contribute to multigenerational acclimation and adaptation to environmental stressors. Brook charr (), an economically important salmonid, is highly sensitive to thermal stress and is of conservation concern in the context of climate change. We studied the effects of temperature during parental sexual maturation and offspring rearing on whole-genome DNA methylation in brook charr juveniles (fry). Parents were split between warm and cold temperatures during sexual maturation, mated in controlled breeding designs, then offspring from each family were split between warm (8°C) and cold (5°C) rearing environments. Using whole-genome bisulfite sequencing, we found 188 differentially methylated regions (DMRs) due to parental maturation temperature after controlling for family structure. By contrast, offspring rearing temperature had a negligible effect on offspring methylation. Stable intergenerational inheritance of DNA methylation and minimal plasticity in progeny could result in the transmission of acclimatory epigenetic states to offspring, priming them for a warming environment. Our findings have implications pertaining to the role of intergenerational epigenetic inheritance in response to ongoing climate change.
Topics: Acclimatization; Animals; DNA Methylation; Epigenesis, Genetic; Sexual Maturation; Trout
PubMed: 35506232
DOI: 10.1098/rspb.2022.0670 -
Scientific Reports Jun 2021Different strategies are used to meet optimal reproductive performance or manage reproductive health. Although exogenous human chorionic gonadotropin (hCG) and...
Endocrine and molecular milieus of ovarian follicles are diversely affected by human chorionic gonadotropin and gonadotropin-releasing hormone in prepubertal and mature gilts.
Different strategies are used to meet optimal reproductive performance or manage reproductive health. Although exogenous human chorionic gonadotropin (hCG) and gonadotropin-releasing hormone (GnRH) agonists (A) are commonly used to trigger ovulation in estrous cycle synchronization, little is known about their effect on the ovarian follicle. Here, we explored whether hCG- and GnRH-A-induced native luteinizing hormone (LH) can affect the endocrine and molecular milieus of ovarian preovulatory follicles in pigs at different stages of sexual development. We collected ovaries 30 h after hCG/GnRH-A administration from altrenogest and pregnant mare serum gonadotropin (eCG)-primed prepubertal and sexually mature gilts. Several endocrine and molecular alternations were indicated, including broad hormonal trigger-induced changes in follicular fluid steroid hormones and prostaglandin levels. However, sexual maturity affected only estradiol levels. Trigger- and/or maturity-dependent changes in the abundance of hormone receptors (FSHR and LHCGR) and proteins associated with lipid metabolism and steroidogenesis (e.g., STAR, HSD3B1, and CYP11A1), prostaglandin synthesis (PTGS2 and PTGFS), extracellular matrix remodeling (MMP1 and TIMP1), protein folding (HSPs), molecular transport (TF), and cell function and survival (e.g., VIM) were observed. These data revealed different endocrine properties of exogenous and endogenous gonadotropins, with a potent progestational/androgenic role of hCG and estrogenic/pro-developmental function of LH.
Topics: Animals; Chorionic Gonadotropin; Estrous Cycle; Female; Gonadotropin-Releasing Hormone; Humans; Ovarian Follicle; Ovulation; Sexual Maturation; Swine
PubMed: 34188064
DOI: 10.1038/s41598-021-91434-6 -
Frontiers in Neuroendocrinology Oct 2014The mammalian reproductive hormone axis regulates gonadal steroid hormone levels and gonadal function essential for reproduction. The neuroendocrine control of the axis... (Review)
Review
The mammalian reproductive hormone axis regulates gonadal steroid hormone levels and gonadal function essential for reproduction. The neuroendocrine control of the axis integrates signals from a wide array of inputs. The regulatory pathways important for mediating these inputs have been the subject of numerous studies. One class of proteins that have been shown to mediate metabolic and growth signals to the CNS includes Insulin and IGF-1. These proteins are structurally related and can exert endocrine and growth factor like action via related receptor tyrosine kinases. The role that insulin and IGF-1 play in controlling the hypothalamus and pituitary and their role in regulating puberty and nutritional control of reproduction has been studied extensively. This review summarizes the in vitro and in vivo models that have been used to study these neuroendocrine structures and the influence of these growth factors on neuroendocrine control of reproduction.
Topics: Animals; Humans; Insulin; Insulin-Like Growth Factor I; Neurosecretory Systems; Pituitary Gland; Reproduction; Sexual Maturation
PubMed: 24929098
DOI: 10.1016/j.yfrne.2014.05.007 -
PloS One 2017Epidemiological studies indicate associations between childhood exposure with phthalates and bisphenol A (BPA) and the pubertal development. We examined associations...
OBJECTIVE
Epidemiological studies indicate associations between childhood exposure with phthalates and bisphenol A (BPA) and the pubertal development. We examined associations between the pre-pubertal phthalate and BPA body burden and the longitudinally assessed sexual maturation of eight- to thirteen-year-old children.
METHODS
We started with eight- to ten-year-old children in the baseline study and quantified phthalate metabolites and BPA in 472 urine samples (250 boys; 222 girls; mean age: 8.8 years). Associations between the pubertal development, assessed in three annual follow-up studies by Puberty Development scale questionnaires (PD scales), and the chemical exposure from the baseline visit were longitudinally analyzed with generalized estimation equations.
RESULTS
The number of children with both chemical measures and PD scores (calculated from the PD scales) was 408. In the third follow-up, 49% of the girls and 18% of the boys had reached mid-puberty. For girls, we observed a delayed pubertal development with the di-hexyl-ethyl phthalate (DEHP) metabolites (β: -0.16 to -0.23; p ≤ 0.05 or p ≤ 0.1), mono-n-butyl phthalate (β: -0.15; 95% CI: -0.31; 0.01), mono-benzyl phthalate (β: -0.11; 95% CI: -0,24; -0,01), and mono-ethyl phthalate (MEP) (β: -0.15; 95% CI: -0.28; -0.01). In addition, significant non-linear associations of the DEHP metabolites and BPA with the PD scores were found, when their quadratic effects were included in the GEE models. In boys, no consistent relationships between the PD scores and the chemicals were detected except of an accelerated development with the ∑DEHP metabolites (β: 0.16; 95% CI: -0.02; -0.34).
CONCLUSION
We found indications that pre-pubertal exposures with phthalates and BPA were associated with pubertal timing in children, particularly in girls. For boys, associations were inconsistent, and not necessarily in line with the known anti-androgenicity of some phthalates during prenatal exposure.
Topics: Adolescent; Benzhydryl Compounds; Child; Environmental Exposure; Environmental Pollutants; Female; Follow-Up Studies; Humans; Male; Models, Statistical; Phenols; Phthalic Acids; Puberty; Sex Factors; Sexual Maturation; Surveys and Questionnaires
PubMed: 29155850
DOI: 10.1371/journal.pone.0187922 -
Poultry Science Feb 2009A study was performed to assess the effect of reducing BW variability on sexual maturation and reproductive performance of broiler breeder hens. A total of 208 Ross 708...
A study was performed to assess the effect of reducing BW variability on sexual maturation and reproductive performance of broiler breeder hens. A total of 208 Ross 708 1-d-old pullets were randomly assigned at hatch to 1 of 2 feed allocation treatments starting at 16 wk of age when all birds were placed in individual cages. A control treatment had feed allocated on a group basis (GRP) and followed the recommended BW target. A second treatment had feed allocated on an individual bird basis (IND). By design, the BW of IND pullets converged at 20 wk. This design dictated that IND birds had a lower BW variability and a higher feed intake variability than GRP birds. Pullets were retrospectively classified into 3 initial (16 wk) BW categories: low, average, or high, using the mean+/-0.5 SD as threshold. After their first egg, 64 birds were killed and dissected for determination of fleshing, fatness, and reproductive morphology. Egg production traits were analyzed to 60 wk, when the remaining birds were killed and dissected. Reducing BW variability did not reduce variability of age, follicle numbers, and ovary and oviduct weight at sexual maturity. The IND feed allocation accelerated the onset of production of low BW birds, which increased total egg production (177 eggs) and average sequence length (3.9 d) with respect to GRP x low birds (163 eggs; 3.0 d). However, INDxlow hens produced more eggs<52 g than GRPxlow hens (22 versus 8 eggs). The IND treatment increased variability of ovary weight, large yellow follicle number, and large yellow follicle weight at 60 wk. Reducing BW variability increased variation in ovarian morphology at the end of production, which suggests that optimal BW for reproduction varied among birds. Correcting BW from 16 wk to reach the BW target primarily affected low initial BW pullets, which entered lay sooner and produced more eggs, although 91% of the additional eggs weighed<52 g.
Topics: Animals; Body Composition; Body Weight; Chickens; Eating; Feeding Methods; Female; Ovary; Oviposition; Ovum; Random Allocation; Reproduction; Sexual Maturation; Time Factors
PubMed: 19151361
DOI: 10.3382/ps.2008-00165 -
Biomolecules Feb 2021Currently (2020), Africa and Asia are experiencing the worst desert locust () plague in decades. Exceptionally high rainfall in different regions caused favorable...
Currently (2020), Africa and Asia are experiencing the worst desert locust () plague in decades. Exceptionally high rainfall in different regions caused favorable environmental conditions for very successful reproduction and population growth. To better understand the molecular mechanisms responsible for this remarkable reproductive capacity, as well as to fill existing knowledge gaps regarding the regulation of male reproductive physiology, we investigated the role of methoprene-tolerant (-Met) and Taiman (-Tai), responsible for transducing the juvenile hormone (JH) signal, in adult male locusts. We demonstrated that knockdown of these components by RNA interference strongly inhibits male sexual maturation, severely disrupting reproduction. This was evidenced by the inability to show mating behavior, the absence of a yellow-colored cuticle, the reduction of relative testes weight, and the drastically reduced phenylacetonitrile (PAN) pheromone levels of the treated males. We also observed a reduced relative weight, as well as relative protein content, of the male accessory glands in -Met knockdown locusts. Interestingly, in these animals the size of the (CA), the endocrine glands where JH is synthesized, was significantly increased, as well as the transcript level of JH acid methyltransferase (JHAMT), a rate-limiting enzyme in the JH biosynthesis pathway. Moreover, other endocrine pathways appeared to be affected by the knockdown, as evidenced by changes in the expression levels of the insulin-related peptide and two neuroparsins in the fat body. Our results demonstrate that JH signaling pathway components play a crucial role in male reproductive physiology, illustrating their potential as molecular targets for pest control.
Topics: Adaptation, Physiological; Animals; Grasshoppers; Juvenile Hormones; Male; Methoprene; RNA Interference; Receptors, Cell Surface; Reproduction; Sexual Maturation; Signal Transduction
PubMed: 33572050
DOI: 10.3390/biom11020244 -
Marine Biotechnology (New York, N.Y.) Feb 2014In Atlantic salmon aquaculture, early sexual maturation represents a major problem for producers. This is especially true for grilse, which mature after one sea winter...
In Atlantic salmon aquaculture, early sexual maturation represents a major problem for producers. This is especially true for grilse, which mature after one sea winter before reaching a desirable harvest weight, rather than after two sea winters. Salmon maturing as grilse have a much lower market value than later maturing individuals. For this reason, most companies desire fish that grow fast and mature late. Marker-assisted selection has the potential to improve the efficiency of selection against early maturation and for late sexual maturation; however, studies identifying age of sexual maturation-related genetic markers are lacking for Atlantic salmon. Therefore, we used a 6.5K single-nucleotide polymorphism (SNP) array to genotype five families from the Mainstream Canada broodstock program and search for SNPs associated with early (grilsing) or late sexual maturation. There were 529 SNP loci that were variable across all five families, and this was the set that was used for quantitative trait loci (QTL) analysis. GridQTL identified two chromosomes, Ssa10 and Ssa21, containing QTL related to grilsing. In contrast, only one QTL, on Ssa18, was found linked to late maturation in Atlantic salmon. Our previous work on these five families did not identify genome-wide significant growth-related QTL on Ssa10, Ssa21, or Ssa18. Therefore, taken together, these results suggest that both grilsing and late sexual maturation are controlled independently of one another and also from growth-related traits. The identification of genomic regions associated with grilsing or late sexual maturation provide an opportunity to incorporate this information into selective breeding programs that will enhance Atlantic salmon farming.
Topics: Animals; Breeding; Canada; Chromosome Mapping; Genetic Markers; Genotype; Life Cycle Stages; Phenotype; Polymorphism, Single Nucleotide; Quantitative Trait Loci; Salmo salar; Sexual Maturation
PubMed: 23912817
DOI: 10.1007/s10126-013-9530-3 -
Journal of Evolutionary Biology Mar 2009The trade-off between gametes and soma is central to life history evolution. Oosorption has been proposed as a mechanism by which females can redirect nutrients invested...
The trade-off between gametes and soma is central to life history evolution. Oosorption has been proposed as a mechanism by which females can redirect nutrients invested in oocytes into survival when conditions for reproduction are poor. Although positive correlations between oocyte degradation and lifespan have been documented in oviparous insects, the adaptive significance of this process in species with more complex reproductive biology has not been explored. Further, environmental condition is a multivariate state, and combinations of environmental stresses may interact in unpredictable ways. Previous work on the ovoviviparous cockroach, Nauphoeta cinerea, revealed that females manipulated to mate late relative to sexual maturation experience age-related loss in fecundity because of loss of viable oocytes via apoptosis. This loss in fecundity is correlated with a reduction in female mate choice. Food deprivation while mating is delayed further increases levels of oocyte apoptosis, but the relationship between starvation-induced apoptosis and life history are unknown. To investigate this, virgin females were either fed or starved from eclosion until provided with a mate at a time known to be suboptimal for fertility. Following mating, females were fed for the duration of their lifespan. We measured lifetime reproductive performance. Contrary to predictions, under conditions of delayed mating opportunity, starved females had greater fecundity, gave birth to more high-quality offspring and had increased longevity compared with that of fed females. We suggest that understanding proximal mechanisms underlying life history trade-offs, including the function of oocyte apoptosis, and how these mechanisms respond to varied environmental conditions is critical.
Topics: Animals; Diet; Female; Fertility; Male; Random Allocation; Sexual Behavior, Animal; Sexual Maturation; Starvation; Time Factors
PubMed: 19170814
DOI: 10.1111/j.1420-9101.2008.01671.x