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Breast Cancer Research : BCR Mar 2024Breast density (BD) is a strong risk factor for breast cancer. Little is known about how BD develops during puberty. Understanding BD trajectories during puberty and its...
BACKGROUND
Breast density (BD) is a strong risk factor for breast cancer. Little is known about how BD develops during puberty. Understanding BD trajectories during puberty and its determinants could be crucial for promoting preventive actions against breast cancer (BC) at early ages. The objective of this research is to characterize % fibroglandular volume (%FGV), absolute fibroglandular volume (AFGV), and breast volume (BV) at different breast Tanner stages until 4-year post menarche in a Latino cohort and to assess determinants of high %FGV and AFGV during puberty and in a fully mature breast.
METHODS
This is a longitudinal follow-up of 509 girls from low-middle socioeconomic status of the Southeast area of Santiago, recruited at a mean age of 3.5 years. The inclusion criteria were singleton birth born, birthweight between 2500 and 4500 g with no medical or mental disorder. A trained dietitian measured weight and height since 3.5 years old and sexual maturation from 8 years old (breast Tanner stages and age at menarche onset). Using standardized methods, BD was measured using dual-energy X-ray absorptiometry (DXA) in various developmental periods (breast Tanner stage B1 until 4 years after menarche onset).
RESULTS
In the 509 girls, we collected 1,442 breast DXA scans; the mean age at Tanner B4 was 11.3 years. %FGV increased across breast Tanner stages and peaked 250 days after menarche. AFGV and BV peaked 2 years after menarche onset. Girls in the highest quartiles of %FGV, AFGV, and BV at Tanner B4 and B5 before menarche onset had the highest values thereafter until 4 years after menarche onset. The most important determinants of %FGV and AFGV variability were BMI z-score (R = 44%) and time since menarche (R = 42%), respectively.
CONCLUSION
We characterize the breast development during puberty, a critical window of susceptibility. Although the onset of menarche is a key milestone for breast development, we observed that girls in the highest quartiles of %FGV and AFGV tracked in that group afterwards. Following these participants in adulthood would be of interest to understand the changes in breast composition during this period and its potential link with BC risk.
Topics: Female; Humans; Child, Preschool; Child; Cohort Studies; Breast Neoplasms; Chile; Puberty; Menarche; Obesity
PubMed: 38475816
DOI: 10.1186/s13058-024-01793-x -
Neuroendocrinology 2019To attain sexual competence, all mammalian species go through puberty, a maturational period during which body growth and development of secondary sexual characteristics... (Review)
Review
To attain sexual competence, all mammalian species go through puberty, a maturational period during which body growth and development of secondary sexual characteristics occur. Puberty begins when the diurnal pulsatile gonadotropin-releasing hormone (GnRH) release from the hypothalamus increases for a prolonged period of time, driving the adenohypophysis to increase the pulsatile release of luteinizing hormone with diurnal periodicity. Increased pubertal GnRH secretion does not appear to be driven by inherent changes in GnRH neuronal activity; rather, it is induced by changes in transsynaptic and glial inputs to GnRH neurons. We now know that these changes involve a reduction in inhibitory transsynaptic inputs combined with increased transsynaptic and glial excitatory inputs to the GnRH neuronal network. Although the pubertal process is known to have a strong genetic component, during the last several years, epigenetics has been implicated as a significant regulatory mechanism through which GnRH release is first repressed before puberty and is involved later on during the increase in GnRH secretion that brings about the pubertal process. According to this concept, a central target of epigenetic regulation is the transcriptional machinery of neurons implicated in stimulating GnRH release. Here, we will briefly review the hormonal changes associated with the advent of female puberty and the role that excitatory transsynaptic inputs have in this process. In addition, we will examine the 3 major groups of epigenetic modifying enzymes expressed in the neuroendocrine hypothalamus, which was recently shown to be involved in pubertal development and progression.
Topics: Animals; Chromatin; Epigenesis, Genetic; Female; Humans; Puberty; Sexual Maturation
PubMed: 30731454
DOI: 10.1159/000497745 -
Developmental Cognitive Neuroscience Dec 2022Adolescence is defined by puberty and represents a period characterized by neural circuitry maturation (e.g., fronto-striatal systems) facilitating cognitive...
Adolescence is defined by puberty and represents a period characterized by neural circuitry maturation (e.g., fronto-striatal systems) facilitating cognitive improvements. Though studies have characterized age-related changes, the extent to which puberty influences maturation of fronto-striatal networks is less known. Here, we combine two longitudinal datasets to characterize the role of puberty in the development of fronto-striatal resting-state functional connectivity (rsFC) and its relationship to inhibitory control in 106 10-18-year-olds. Beyond age effects, we found that puberty was related to decreases in rsFC between the caudate and the anterior vmPFC, rostral and ventral ACC, and v/dlPFC, as well as with rsFC increases between the dlPFC and nucleus accumbens (NAcc) across males and females. Stronger caudate rsFC with the dlPFC and vlPFC during early puberty was associated with worse inhibitory control and slower correct responses, respectively, whereas by late puberty, stronger vlPFC rsFC with the dorsal striatum was associated with faster correct responses. Taken together, our findings suggest that certain fronto-striatal connections are associated with pubertal maturation beyond age effects, which, in turn are related to inhibitory control. We discuss implications of puberty-related fronto-striatal maturation to further our understanding of pubertal effects related to adolescent cognitive and affective neurodevelopment.
Topics: Adolescent; Male; Female; Humans; Adolescent Development; Magnetic Resonance Imaging; Corpus Striatum; Puberty; Nucleus Accumbens
PubMed: 36495791
DOI: 10.1016/j.dcn.2022.101183 -
International Journal of Public Health Mar 2019This study presents a scoping review of evidence relating to knowledge and experiences of puberty and menstruation among females aged 10-14 years in low- and... (Meta-Analysis)
Meta-Analysis
OBJECTIVES
This study presents a scoping review of evidence relating to knowledge and experiences of puberty and menstruation among females aged 10-14 years in low- and middle-income countries.
METHODS
Forty-four items from 12 countries were identified from a systematic scoping review and screening of 8083 items. Included studies were quality assessed.
RESULTS
A majority (40/44) of studies used school-based samples, and fifteen studies reported on interventions. Girls had inadequate knowledge about menstruation; menarche as a trigger for girls learning about menstruation was common. Adolescents struggled with menstrual hygiene. Negative emotions were associated with menarche and menstrual management. A minority of studies dealt explicitly with puberty. Most girls obtained information about menstruation and/or puberty from their mothers, although mothers were not necessarily girls' preferred source for learning about these topics.
CONCLUSIONS
Young adolescent girls are under-prepared for puberty and menstruation. Predominantly school-based studies mean we know little about young out-of-school adolescents. The evidence base lags behind the rise in interest from practitioners as well as the development (and evaluation) of puberty and/or menstruation interventions.
Topics: Adolescent; Child; Female; Health Knowledge, Attitudes, Practice; Humans; Income; Menarche; Menstruation; Poverty; Puberty
PubMed: 30740629
DOI: 10.1007/s00038-019-01209-0 -
PloS One 2021The objective of this systematic review was to evaluate the association between a soy-based infant diet and the onset of puberty. We included studies in which children... (Meta-Analysis)
Meta-Analysis
The objective of this systematic review was to evaluate the association between a soy-based infant diet and the onset of puberty. We included studies in which children were fed a soy-based diet, and we compared them with those who were not. The primary outcomes were the onset of puberty in girls (thelarche, pubarche, and menarche age), boys (pubarche, voice change, testicular and penis enlargement age), and both (risk of delayed and precocious puberty [PP]). Search strategies were performed in PubMed, Embase, LILACS, and CENTRAL databases. Two reviewers selected eligible studies, assessed the risk of bias, and extracted data from the included studies. The odds ratio (OR) and mean difference (MD) were calculated with a 95% confidence interval (CI) as a measure of the association between soy consumption and outcomes. We used a random-effects model to pool results across studies and the Grading of Recommendations Assessment, Development, and Evaluation to evaluate the certainty of evidence. We included eight studies in which 598 children consumed a soy-based diet but 2957 did not. The primary outcomes that could be plotted in the meta-analysis were the risk of PP and age at menarche. There was no statistical difference between groups for PP (OR: 0.51, 95% CI: 0.09 to 2.94, 3 studies, 206 participants, low certainty of evidence). No between-group difference was observed in menarche age (MD 0.14 years, 95% CI -0.16 to 0.45, 3 studies, 605 children, low certainty of evidence). One study presented this outcome in terms of median and interquartile range, and although the onset of menarche was marginally increased in girls who received a soy-based diet, the reported age was within the normal age range for menarche. We did not find any association between a soy-based infant diet and the onset of puberty in boys or girls. Trial Registration: PROSPERO registration: CRD42018088902.
Topics: Child, Preschool; Databases, Factual; Diet; Female; Humans; Infant Food; Infant, Newborn; Male; Menarche; Puberty; Soy Foods
PubMed: 34003856
DOI: 10.1371/journal.pone.0251241 -
Asian Journal of Andrology 2023Puberty is a pivotal biological process that completes sexual maturation to achieve full reproductive capability. It is a major transformational period of life, whose... (Review)
Review
Puberty is a pivotal biological process that completes sexual maturation to achieve full reproductive capability. It is a major transformational period of life, whose timing is strongly affected by genetic makeup of the individual, along with various internal and external factors. Although the exact mechanism for initiation of the cascade of molecular events that culminate in puberty is not yet known, the process of pubertal onset involves interaction of numerous complex signaling pathways of hypothalamo-pituitary-testicular (HPT) axis. We developed a classification of the mechanisms involved in male puberty that allowed placing many genes into physiological context. These include (i) hypothalamic development during embryogenesis, (ii) synaptogenesis where gonadotropin releasing hormone (GnRH) neurons form neuronal connections with suprahypothalamic neurons, (iii) maintenance of neuron homeostasis, (iv) regulation of synthesis and secretion of GnRH, (v) appropriate receptors/proteins on neurons governing GnRH production and release, (vi) signaling molecules activated by the receptors, (vii) the synthesis and release of GnRH, (viii) the production and release of gonadotropins, (ix) testicular development, (x) synthesis and release of steroid hormones from testes, and (xi)the action of steroid hormones in downstream effector tissues. Defects in components of this system during embryonic development, childhood/adolescence, or adulthood may disrupt/nullify puberty, leading to long-term male infertility and/or hypogonadism. This review provides a list of 598 genes involved in the development of HPT axis and classified according to this schema. Furthermore, this review identifies a subset of 75 genes for which genetic mutations are reported to delay or disrupt male puberty.
Topics: Adolescent; Male; Humans; Adult; Child; Gonadotropin-Releasing Hormone; Gonadotropins; Hypogonadism; Testis; Puberty; Sexual Maturation
PubMed: 35532554
DOI: 10.4103/aja202210 -
Frontiers in Neuroendocrinology Jan 2013Kisspeptin, encoded by the Kiss1 gene, is a neuropeptide required for puberty and adult reproductive function. Understanding the regulation and development of the... (Review)
Review
Kisspeptin, encoded by the Kiss1 gene, is a neuropeptide required for puberty and adult reproductive function. Understanding the regulation and development of the kisspeptin system provides valuable knowledge about the physiology of puberty and adult fertility, and may provide insights into human pubertal or reproductive disorders. Recent studies, particularly in rodent models, have assessed how kisspeptin neurons develop and how hormonal and non-hormonal factors regulate this developmental process. Exposure to sex steroids (testosterone and estradiol) during critical periods of development can induce organizational (permanent) effects on kisspeptin neuron development, with respect to both sexually dimorphic and non-sexually dimorphic aspects of kisspeptin biology. In addition, sex steroids can also impart activational (temporary) effects on kisspeptin neurons and Kiss1 gene expression at various times during neonatal and peripubertal development, as they do in adulthood. Here, we discuss the current knowledge--and in some cases, lack thereof--of the influence of hormones and other factors on kisspeptin neuronal development.
Topics: Animals; Female; Gonadal Steroid Hormones; Kisspeptins; Male; Neurogenesis; Neurons; Puberty; Sex Characteristics
PubMed: 22728025
DOI: 10.1016/j.yfrne.2012.06.001 -
Molecular and Cellular Endocrinology Aug 2010Puberty is an important developmental stage during which reproductive capacity is attained. The timing of puberty varies greatly among healthy individuals in the general... (Review)
Review
Puberty is an important developmental stage during which reproductive capacity is attained. The timing of puberty varies greatly among healthy individuals in the general population and is influenced by both genetic and environmental factors. Although genetic variation is known to influence the normal spectrum of pubertal timing, the specific genes involved remain largely unknown. Genetic analyses have identified a number of genes responsible for rare disorders of pubertal timing such as hypogonadotropic hypogonadism and Kallmann syndrome. Recently, the first loci with common variation reproducibly associated with population variation in the timing of puberty were identified at 6q21 in or near LIN28B and at 9q31.2. However, these two loci explain only a small fraction of the genetic contribution to population variation in pubertal timing, suggesting the need to continue to consider other loci and other types of variants. Here we provide an update of the genes implicated in disorders of puberty, discuss genes and pathways that may be involved in the timing of normal puberty, and suggest additional avenues of investigation to identify genetic regulators of puberty in the general population.
Topics: Genetic Diseases, Inborn; Genetic Variation; Genetics, Population; Humans; Puberty; Time Factors
PubMed: 20144687
DOI: 10.1016/j.mce.2010.01.038 -
Journal of Research on Adolescence :... Mar 2019Decades of puberty research have yielded key scientific discoveries. Building on the field's rich history, we highlight four understudied populations: youth of color,... (Review)
Review
Decades of puberty research have yielded key scientific discoveries. Building on the field's rich history, we highlight four understudied populations: youth of color, boys, sexual minority youth, and gender minority youth. We explore why scientific study has been slow to evolve in these groups and propose paths forward for exciting new work. For ethnically racially diverse youth, we discuss the need to incorporate culture and context. For boys, we highlight methodological issues and challenges of mapping existing conceptual models onto boys. For sexual and gender minority youth, we discuss unique challenges during puberty and suggest ways to better capture their experiences. With an eye toward a new era, we make recommendations for next steps and underscore the importance of transdisciplinary research.
Topics: Adolescent; Adolescent Health; Community-Based Participatory Research; Cultural Competency; Ethnicity; Female; Humans; Male; Psychology, Adolescent; Puberty; Sexual Maturation; Sexual and Gender Minorities
PubMed: 30869847
DOI: 10.1111/jora.12402 -
Hormones and Behavior Jul 2013This article is part of a Special Issue "Puberty and Adolescence". Puberty is one of the most frequently discussed risk periods for the development of eating disorders.... (Review)
Review
This article is part of a Special Issue "Puberty and Adolescence". Puberty is one of the most frequently discussed risk periods for the development of eating disorders. Prevailing theories propose environmentally mediated sources of risk arising from the psychosocial effects (e.g., increased body dissatisfaction, decreased self-esteem) of pubertal development in girls. However, recent research highlights the potential role of ovarian hormones in phenotypic and genetic risk for eating disorders during puberty. The goal of this paper is to review data from human and animal studies in support of puberty as a critical risk period for eating disorders and evaluate the evidence for hormonal contributions. Data are consistent in suggesting that both pubertal status and pubertal timing significantly impact risk for most eating disorders in girls, such that advanced pubertal development and early pubertal timing are associated with increased rates of eating disorders and their symptoms in both cross-sectional and longitudinal research. Findings in boys have been much less consistent and suggest a smaller role for puberty in risk for eating disorders in boys. Twin and animal studies indicate that at least part of the female-specific risk is due to genetic factors associated with estrogen activation at puberty. In conclusion, data thus far support a role for puberty in risk for eating disorders and highlight the need for additional human and animal studies of hormonal and genetic risk for eating disorders during puberty.
Topics: Adolescent; Animals; Critical Period, Psychological; Feeding and Eating Disorders; Female; Humans; Male; Puberty; Risk Factors; Sexual Maturation; Twin Studies as Topic
PubMed: 23998681
DOI: 10.1016/j.yhbeh.2013.02.019