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Nicholas B. Allen - One of the best experts on this subject based on the ideXlab platform.
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a systematic review of Adrenarche as a sensitive period in neurobiological development and mental health
Developmental Cognitive Neuroscience, 2017Co-Authors: Michelle L. Byrne, Sarah Whittle, Nandita Vijayakumar, Meg Dennison, Julian G. Simmons, Nicholas B. AllenAbstract:Abstract Substantial hormonal and neurobiological changes occur during puberty, and are widely argued to render this period of life a sensitive period in terms of risk for mental health problems. However, there is a paucity of research focusing on Adrenarche, the earlier phase of pubertal development. Furthermore, there is a limited understanding of the association between Adrenarche and neural development during this phase of life. We systematically reviewed research examining human Adrenarcheal development as operationalized by hormonal levels of DHEA and DHEA-S, in relation to indices of mental health (Systematic Review 1). We then reviewed the limited amount of literature that has examined the association between Adrenarcheal development and brain structure or function (Systematic Review 2). In general, studies showed that earlier timing of Adrenarche was associated with greater mental health symptoms, and there is emerging support that brain development plays a role in this relationship. However, several methodological inconsistencies were noted. We propose that future research in this area test a theoretical model of Adrenarche as a sensitive period of neurobiological development, whereby timing of exposure to hormones interacts with brain development, biological sex, and psychosocial stress to influence environmental sensitivity and risk for mental health problems through adolescence.
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A systematic review of Adrenarche as a sensitive period in neurobiological development and mental health
Elsevier, 2017Co-Authors: Michelle L. Byrne, Sarah Whittle, Nandita Vijayakumar, Meg Dennison, Julian G. Simmons, Nicholas B. AllenAbstract:Substantial hormonal and neurobiological changes occur during puberty, and are widely argued to render this period of life a sensitive period in terms of risk for mental health problems. However, there is a paucity of research focusing on Adrenarche, the earlier phase of pubertal development. Furthermore, there is a limited understanding of the association between Adrenarche and neural development during this phase of life. We systematically reviewed research examining human Adrenarcheal development as operationalized by hormonal levels of DHEA and DHEA-S, in relation to indices of mental health (Systematic Review 1). We then reviewed the limited amount of literature that has examined the association between Adrenarcheal development and brain structure or function (Systematic Review 2). In general, studies showed that earlier timing of Adrenarche was associated with greater mental health symptoms, and there is emerging support that brain development plays a role in this relationship. However, several methodological inconsistencies were noted. We propose that future research in this area test a theoretical model of Adrenarche as a sensitive period of neurobiological development, whereby timing of exposure to hormones interacts with brain development, biological sex, and psychosocial stress to influence environmental sensitivity and risk for mental health problems through adolescence. Keywords: Puberty, Adrenarche, Sensitive periods, Mental health, Brain developmen
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STUDY PROTOCOL Open Access Study protocol: the Childhood to Adolescence Transition Study (CATS)
2016Co-Authors: Centre For Adolescent Health, Julian G. Simmons, Nicholas B. Allen, The Royal, Lisa K Mundy, Russell M Viner, Jordana K Bayer, Timothy Olds, Louisa Degenhardt, Rosa AlatiAbstract:Background: Puberty is a multifaceted developmental process that begins in late-childhood with a cascade of endocrine changes that ultimately lead to sexual maturation and reproductive capability. The transition through puberty is marked by an increased risk for the onset of a range of health problems, particularly those related to the control of behaviour and emotion. Early onset puberty is associated with a greater risk of cancers of the reproductive tract and cardiovascular disease. Previous studies have had methodological limitations and have tended to view puberty as a unitary process, with little distinction between Adrenarche, gonadarche and linear growth. The Childhood to Adolescence Transition Study (CATS) aims to prospectively examine associations between the timing and stage of the different hormonally-mediated changes, as well as the onset and course of common health and behavioural problems that emerge in the transition from childhood to adolescence. The initial focus of CATS is on Adrenarche, the first hormonal process in the pubertal cascade, which begins for most children at around 8 years of age. Methods/Design: CATS is a longitudinal population-based cohort study. All Grade 3 students (8–9 years of age) from a stratified cluster sample of schools in Melbourne, Australia were invited to take part. In total, 1239 students and a parent/guardian were recruited to participate in the study. Measures are repeated annually and compris
J Dimartinonardi - One of the best experts on this subject based on the ideXlab platform.
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decreased insulin sensitivity in prepubertal girls with premature Adrenarche and acanthosis nigricans
The Journal of Clinical Endocrinology and Metabolism, 1995Co-Authors: E Oppenheimer, B Linder, J DimartinonardiAbstract:Benign premature Adrenarche (PA) is the term used to refer to girls with the early development of pubic hair before the age of 8 yr and is characterized by mild hyperandrogenism. Hyperandrogenism in adult women is often not as benign and has been associated with insulin resistance, acanthosis nigricans (AN), and the polycystic ovary syndrome. We have seen a group of young girls with PA who have also been found to have AN. The purpose of this study was to determine whether there are any clinical and biochemical differences in those girls with PA with and without AN. Twelve girls with PA were divided into two groups at the time of evaluation: group I, those without AN (n = 5); and group II, those with AN (n = 7). Adrenal androgen levels were determined in all subjects by a 60-min ACTH stimulation test. Insulin sensitivity was measured by the frequently sampled iv glucose tolerance test with tolbutamide and was assessed using the modified minimal model. Mean chronological age, bone age, and weight for length...
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decreased insulin sensitivity in prepubertal girls with premature Adrenarche and acanthosis nigricans
The Journal of Clinical Endocrinology and Metabolism, 1995Co-Authors: E Oppenheimer, B Linder, J DimartinonardiAbstract:Benign premature Adrenarche (PA) is the term used to refer to girls with the early development of pubic hair before the age of 8 yr and is characterized by mild hyperandrogenism. Hyperandrogenism in adult women is often not as benign and has been associated with insulin resistance, acanthosis nigricans (AN), and the polycystic ovary syndrome. We have seen a group of young girls with PA who have also been found to have AN. The purpose of this study was to determine whether there are any clinical and biochemical differences in those girls with PA with and without AN. Twelve girls with PA were divided into two groups at the time of evaluation: group I, those without AN (n = 5); and group II, those with AN (n = 7). Adrenal androgen levels were determined in all subjects by a 60-min ACTH stimulation test. Insulin sensitivity was measured by the frequently sampled iv glucose tolerance test with tolbutamide and was assessed using the modified minimal model. Mean chronological age, bone age, and weight for length index were similar in the two groups. The baseline and stimulated levels of adrenal androgens were also not significantly different between the two groups. The group I girls (without AN) had an insulin sensitivity index of 6.75 +/- 1.31, which was in the normal prepubertal range. This was significantly different from that in group II (with AN), who had an insulin sensitivity index of 3.69 +/- 1.29. Therefore, many girls with premature Adrenarche can have AN and decreased insulin sensitivity. Whether these girls have a truly benign course or are at risk of ovarian dysfunction or carbohydrate intolerance needs to be assessed.
Mark R Palmert - One of the best experts on this subject based on the ideXlab platform.
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the longitudinal study of adrenal maturation during gonadal suppression evidence that Adrenarche is a gradual process
The Journal of Clinical Endocrinology and Metabolism, 2001Co-Authors: Mark R Palmert, Douglas Hayden, Joan M Mansfield, J F Crigler, William F Crowley, Donald W Chandler, Paul A BoeppleAbstract:The physical changes that herald the onset of puberty result from the combination of Adrenarche and gonadarche. To examine adrenal maturation and associated changes in growth without the confounding effects of changes in the gonadal steroid milieu, we performed a longitudinal study in 14 young girls with idiopathic central precocious puberty during long-term pituitary-gonadal suppression. Beginning at the mean age of 2.9 yr, dehydroepiandrosterone sulfate levels, linear growth, skeletal maturation, body mass index, and secondary sexual development were evaluated at 3- to 6-month intervals for up to 12.3 yr. In 12 of the girls, levels of dehydroepiandrosterone, androstenedione, 17-hydroxypregnenolone, and 17alpha-hydroxyprogesterone were determined before and after acute ACTH stimulation every 6 months to investigate the maturation of adrenal steroidogenic enzyme activity. Serum dehydroepiandrosterone sulfate levels rose progressively throughout the study. An exponential model fit the longitudinal datasets well and indicated that dehydroepiandrosterone sulfate levels increased approximately 22%/yr from the youngest age onward. Increasing activity of 17-20 lyase (CYP17) and decreasing activity of 3beta-hydroxysteroid dehydrogenase were also evident in preadrenarchal subjects. When controlled for chronological age, no significant associations were noted between weight, body mass index, or body surface area and dehydroepiandrosterone sulfate levels. However, similar analyses revealed modest correlations of both height and growth velocity with dehydroepiandrosterone sulfate levels. Our results suggest that Adrenarche is not the result of sudden rapid changes in adrenal enzyme activities or adrenal androgen concentrations; rather, Adrenarche may be a gradual maturational process that begins in early childhood.
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the longitudinal study of adrenal maturation during gonadal suppression evidence that Adrenarche is a gradual process
The Journal of Clinical Endocrinology and Metabolism, 2001Co-Authors: Mark R Palmert, Douglas Hayden, Joan M Mansfield, J F Crigler, William F Crowley, Donald W Chandler, Paul A BoeppleAbstract:The physical changes that herald the onset of puberty result from the combination of Adrenarche and gonadarche. To examine adrenal maturation and associated changes in growth without the confounding effects of changes in the gonadal steroid milieu, we performed a longitudinal study in 14 young girls with idiopathic central precocious puberty during long-term pituitary-gonadal suppression. Beginning at the mean age of 2.9 yr, dehydroepiandrosterone sulfate levels, linear growth, skeletal maturation, body mass index, and secondary sexual development were evaluated at 3- to 6-month intervals for up to 12.3 yr. In 12 of the girls, levels of dehydroepiandrosterone, androstenedione, 17-hydroxypregnenolone, and 17α-hydroxyprogesterone were determined before and after acute ACTH stimulation every 6 months to investigate the maturation of adrenal steroidogenic enzyme activity. Serum dehydroepiandrosterone sulfate levels rose progressively throughout the study. An exponential model fit the longitudinal datasets wel...
Julian G. Simmons - One of the best experts on this subject based on the ideXlab platform.
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pubertal hormones predict sex specific trajectories of pituitary gland volume during the transition from childhood to adolescence
NeuroImage, 2020Co-Authors: Sarah Whittle, Nandita Vijayakumar, Marjolein E A Barendse, Elena Pozzi, Julian G. SimmonsAbstract:Pituitary gland volume (PGV) increases during childhood and adolescence in a sex-specific manner, and previous research suggests that puberty may be associated with PGV development. However, existing research to date has focused on sex hormones associated with gonadarche. Given the role of the pituitary gland in hypothalamic-pituitary-adrenal (HPA) axis function, the present study investigated associations between PGV development and HPA hormones that play a role in the earlier pubertal phase of Adrenarche. Participants were a community sample of 249 children and early adolescents who participated in longitudinal brain imaging and pubertal assessments. Each participant provided data at one or two waves 1.5-3 years apart, resulting in 409 datasets that covered the age range 8-13 years. PGV was estimated from T1-weighted Magnetic Resonance Imaging (MRI) scans, and dehydroepiandrosterone (DHEA), its sulfate (DHEA-S) and testosterone were measured from saliva. Estradiol was measured for a subset of females. Parents reported on physical pubertal development. Linear mixed modeling was used to investigate associations between age, pubertal measures and PGV development. DHEA, DHEA-S and testosterone (in addition to physical maturation) explained variance in PGV development over and above age, and in a sex-dependent fashion. In all cases, associations were stronger, or only present in females. Estradiol was associated with PGV in females, but this did not appear to account for Adrenarcheal hormone effects. Our findings suggest a key role for the hormones of Adrenarche, the first biochemical phase of puberty, in PGV development. Further research is required to understand the sex-specific role of Adrenarcheal and gonadarcheal hormones on the PGV across development.
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a systematic review of Adrenarche as a sensitive period in neurobiological development and mental health
Developmental Cognitive Neuroscience, 2017Co-Authors: Michelle L. Byrne, Sarah Whittle, Nandita Vijayakumar, Meg Dennison, Julian G. Simmons, Nicholas B. AllenAbstract:Abstract Substantial hormonal and neurobiological changes occur during puberty, and are widely argued to render this period of life a sensitive period in terms of risk for mental health problems. However, there is a paucity of research focusing on Adrenarche, the earlier phase of pubertal development. Furthermore, there is a limited understanding of the association between Adrenarche and neural development during this phase of life. We systematically reviewed research examining human Adrenarcheal development as operationalized by hormonal levels of DHEA and DHEA-S, in relation to indices of mental health (Systematic Review 1). We then reviewed the limited amount of literature that has examined the association between Adrenarcheal development and brain structure or function (Systematic Review 2). In general, studies showed that earlier timing of Adrenarche was associated with greater mental health symptoms, and there is emerging support that brain development plays a role in this relationship. However, several methodological inconsistencies were noted. We propose that future research in this area test a theoretical model of Adrenarche as a sensitive period of neurobiological development, whereby timing of exposure to hormones interacts with brain development, biological sex, and psychosocial stress to influence environmental sensitivity and risk for mental health problems through adolescence.
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A systematic review of Adrenarche as a sensitive period in neurobiological development and mental health
Elsevier, 2017Co-Authors: Michelle L. Byrne, Sarah Whittle, Nandita Vijayakumar, Meg Dennison, Julian G. Simmons, Nicholas B. AllenAbstract:Substantial hormonal and neurobiological changes occur during puberty, and are widely argued to render this period of life a sensitive period in terms of risk for mental health problems. However, there is a paucity of research focusing on Adrenarche, the earlier phase of pubertal development. Furthermore, there is a limited understanding of the association between Adrenarche and neural development during this phase of life. We systematically reviewed research examining human Adrenarcheal development as operationalized by hormonal levels of DHEA and DHEA-S, in relation to indices of mental health (Systematic Review 1). We then reviewed the limited amount of literature that has examined the association between Adrenarcheal development and brain structure or function (Systematic Review 2). In general, studies showed that earlier timing of Adrenarche was associated with greater mental health symptoms, and there is emerging support that brain development plays a role in this relationship. However, several methodological inconsistencies were noted. We propose that future research in this area test a theoretical model of Adrenarche as a sensitive period of neurobiological development, whereby timing of exposure to hormones interacts with brain development, biological sex, and psychosocial stress to influence environmental sensitivity and risk for mental health problems through adolescence. Keywords: Puberty, Adrenarche, Sensitive periods, Mental health, Brain developmen
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STUDY PROTOCOL Open Access Study protocol: the Childhood to Adolescence Transition Study (CATS)
2016Co-Authors: Centre For Adolescent Health, Julian G. Simmons, Nicholas B. Allen, The Royal, Lisa K Mundy, Russell M Viner, Jordana K Bayer, Timothy Olds, Louisa Degenhardt, Rosa AlatiAbstract:Background: Puberty is a multifaceted developmental process that begins in late-childhood with a cascade of endocrine changes that ultimately lead to sexual maturation and reproductive capability. The transition through puberty is marked by an increased risk for the onset of a range of health problems, particularly those related to the control of behaviour and emotion. Early onset puberty is associated with a greater risk of cancers of the reproductive tract and cardiovascular disease. Previous studies have had methodological limitations and have tended to view puberty as a unitary process, with little distinction between Adrenarche, gonadarche and linear growth. The Childhood to Adolescence Transition Study (CATS) aims to prospectively examine associations between the timing and stage of the different hormonally-mediated changes, as well as the onset and course of common health and behavioural problems that emerge in the transition from childhood to adolescence. The initial focus of CATS is on Adrenarche, the first hormonal process in the pubertal cascade, which begins for most children at around 8 years of age. Methods/Design: CATS is a longitudinal population-based cohort study. All Grade 3 students (8–9 years of age) from a stratified cluster sample of schools in Melbourne, Australia were invited to take part. In total, 1239 students and a parent/guardian were recruited to participate in the study. Measures are repeated annually and compris
Francis De Zegher - One of the best experts on this subject based on the ideXlab platform.
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precocious pubarche hyperinsulinism and ovarian hyperandrogenism in girls relation to reduced fetal growth
The Journal of Clinical Endocrinology and Metabolism, 1998Co-Authors: Lourdes Ibanez, Neus Potau, Inge Francois, Francis De ZegherAbstract:Pronounced Adrenarche with precocious pubarche (PP) in girls has been associated with hyperinsulinism and subsequent functional ovarian hyperandrogenism (FOH). Recently, pronounced Adrenarche and insulin resistance have each been related to low birth weight. We have now tested the hypothesis that the frequent concurrence of PP with pronounced Adrenarche, FOH, and hyperinsulinemia in girls may be secondary to separate relationships between these conditions and low birth weight. A total of 185 girls (aged 5–18 yr) without endocrinopathy or with PP and pronounced Adrenarche with or without FOH were studied; mean serum insulin (MSI) concentrations were determined after a standardized oral glucose tolerance test. Birth weight sd scores [mean (sem)] of control girls (0.38 ± 0.08; n = 83) were higher (P < 0.0001) than those of PP girls (−0.81 ± 0.13; n = 102). Among postmenarcheal PP girls, birth weight sd scores of girls without FOH (−0.25 ± 0.19; n = 25) were higher (P < 0.0001) than those in girls with FOH (−...
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precocious pubarche hyperinsulinism and ovarian hyperandrogenism in girls relation to reduced fetal growth
The Journal of Clinical Endocrinology and Metabolism, 1998Co-Authors: Lourdes Ibanez, Neus Potau, Inge Francois, Francis De ZegherAbstract:Pronounced Adrenarche with precocious pubarche (PP) in girls has been associated with hyperinsulinism and subsequent functional ovarian hyperandrogenism (FOH). Recently, pronounced Adrenarche and insulin resistance have each been related to low birth weight. We have now tested the hypothesis that the frequent concurrence of PP with pronounced Adrenarche, FOH, and hyperinsulinemia in girls may be secondary to separate relationships between these conditions and low birth weight. A total of 185 girls (aged 5-18 yr) without endocrinopathy or with PP and pronounced Adrenarche with or without FOH were studied; mean serum insulin (MSI) concentrations were determined after a standardized oral glucose tolerance test. Birth weight SD scores [mean (SEM)] of control girls (0.38+/-0.08; n = 83) were higher (P < 0.0001) than those of PP girls (-0.81+/-0.13; n = 102). Among postmenarcheal PP girls, birth weight SD scores of girls without FOH (-0.25+/-0.19; n = 25) were higher (P < 0.0001) than those in girls with FOH (-1.51+/-0.28; n = 23). In pubertal girls (n = 145), MSI levels correlated negatively with birth weight SD scores (r = -0.48; P < 0.05), independently of PP. MSI levels in girls with birth weight below 1 SD (93+/-9 mU/L; n = 33) were higher (P < 0.0001) than those in girls with birth weight between -1 and +1 SD (52+/-2 mU/L; n = 94), whereas glycemia profiles were comparable. Integration of the aforementioned data suggests that there may be a sequence in the associations between reduced fetal growth and components of the postnatal endocrine system; minor fetal growth reduction appears to be associated with amplified Adrenarche, whereas more pronounced prenatal growth restriction seem to precede FOH and hyperinsulinemia during adolescence. In conclusion, these findings corroborate the hypothesis that the frequent concurrence of PP (with pronounced Adrenarche), FOH, and hyperinsulinemia in girls may result from a common early origin (low birth weight serving as a marker), rather than from a direct interrelationship later in life.