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Indian Journal of Pediatrics Oct 2023Enlargement of breasts among boys is termed gynecomastia. This could be due to an alteration in the androgen-estrogen ratio along with the effects of other hormones... (Review)
Review
Enlargement of breasts among boys is termed gynecomastia. This could be due to an alteration in the androgen-estrogen ratio along with the effects of other hormones including growth hormone, insulin like growth factor 1, prolactin, and other factors affecting aromatase enzyme. The common causes of gynecomastia are pubertal gynecomastia, obesity, drugs and hypogonadism. Several other diseases including liver or renal failure, thyrotoxicosis, Klinefelter syndrome, tumors and environmental pollutants can cause gynecomastia. History and clinical examination will help formulate targeted investigations and management. The factors to be evaluated in these include examination of breasts and testes, in addition to other parts of systemic examination. Treatment of underlying disorders can improve gynecomastia, such as use of testosterone in hypogonadism. Some boys may not need any intervention as gynecomastia may resolve on its own. Medical management is useful in simple gynecomastia. Tamoxifen has been tried successfully in adolescents with gynecomastia. Other drugs including clomiphene, danazol, letrozole and anastrozole have not been consistently useful in this age group. In severe chronic gynecomastia, surgery is the treatment of choice.
Topics: Adolescent; Male; Humans; Gynecomastia; Hypertrophy; Tamoxifen; Growth Hormone; Hypogonadism
PubMed: 37592101
DOI: 10.1007/s12098-023-04810-7 -
Endocrine Reviews Jan 2024Kisspeptin (KP) and neurokinin B (NKB) are neuropeptides that govern the reproductive endocrine axis through regulating hypothalamic gonadotropin-releasing hormone... (Review)
Review
Kisspeptin (KP) and neurokinin B (NKB) are neuropeptides that govern the reproductive endocrine axis through regulating hypothalamic gonadotropin-releasing hormone (GnRH) neuronal activity and pulsatile GnRH secretion. Their critical role in reproductive health was first identified after inactivating variants in genes encoding for KP or NKB signaling were shown to result in congenital hypogonadotropic hypogonadism and a failure of pubertal development. Over the past 2 decades since their discovery, a wealth of evidence from both basic and translational research has laid the foundation for potential therapeutic applications. Beyond KP's function in the hypothalamus, it is also expressed in the placenta, liver, pancreas, adipose tissue, bone, and limbic regions, giving rise to several avenues of research for use in the diagnosis and treatment of pregnancy, metabolic, liver, bone, and behavioral disorders. The role played by NKB in stimulating the hypothalamic thermoregulatory center to mediate menopausal hot flashes has led to the development of medications that antagonize its action as a novel nonsteroidal therapeutic agent for this indication. Furthermore, the ability of NKB antagonism to partially suppress (but not abolish) the reproductive endocrine axis has supported its potential use for the treatment of various reproductive disorders including polycystic ovary syndrome, uterine fibroids, and endometriosis. This review will provide a comprehensive up-to-date overview of the preclinical and clinical data that have paved the way for the development of diagnostic and therapeutic applications of KP and NKB.
Topics: Pregnancy; Female; Humans; Neurokinin B; Kisspeptins; Gonadotropin-Releasing Hormone; Reproduction; Hypothalamus
PubMed: 37467734
DOI: 10.1210/endrev/bnad023 -
Frontiers in Endocrinology 2023Idiopathic hypogonadotropic hypogonadism (IHH) is characterized by the absence of pubertal development and subsequent impaired fertility often due to...
Idiopathic hypogonadotropic hypogonadism (IHH) is characterized by the absence of pubertal development and subsequent impaired fertility often due to gonadotropin-releasing hormone (GnRH) deficits. Exome sequencing of two independent cohorts of IHH patients identified 12 rare missense variants in in 15 patients. encodes two distinct isoforms. In the adult mouse, expression of both isoform1 and isoform2 was detected in the brain, pituitary, and gonads. However, only isoform1 was detected in mouse primary GnRH cells and three immortalized GnRH cell lines, two mouse and one human. To date, the function of isoform2 has been verified as a transcription factor, while the function of isoform1 has been unknown. In the present report, bioinformatics and cell assays on a human-derived GnRH cell line reveal a novel function for isoform1, demonstrating it can act as a transcriptional regulator, decreasing expression. In addition, the impact of the two most prevalent variants, identified in five IHH patients, that were located at/or close to the DNA-binding domain was examined. Notably, one of these mutations prevented the repression of GnRH transcripts by isoform1. Normally, GnRH transcription increases as GnRH cells mature as they near migrate into the brain. Augmentation earlier during development can disrupt normal GnRH cell migration, consistent with some POU6F2 variants contributing to the IHH pathogenesis.
Topics: Animals; Humans; Mice; Brain; Gonadotropin-Releasing Hormone; Mutation, Missense; POU Domain Factors; Hypogonadism
PubMed: 37600690
DOI: 10.3389/fendo.2023.1203542 -
The Journal of Clinical Endocrinology... Dec 2023Executive dysfunction is a well-recognized component of the cognitive phenotype of Klinefelter syndrome (KS), yet the neural basis of KS-associated cognitive weaknesses,...
CONTEXT
Executive dysfunction is a well-recognized component of the cognitive phenotype of Klinefelter syndrome (KS), yet the neural basis of KS-associated cognitive weaknesses, and their association with testicular failure is unknown.
OBJECTIVE
We investigated executive function, brain activation, and pubertal development in adolescents with and without KS.
METHODS
Forty-three adolescents with KS (mean age 12.3 ± 2.3 years) and 41 typically developing boys (mean age 11.9 ± 1.8 years) underwent pubertal evaluation, behavioral assessment, and completed functional magnetic resonance imaging (fMRI) as they performed an executive function task, the go/no-go task. Group differences in activation were examined. Associations among activation, executive function, and pubertal development measures were tested in secondary analyses.
RESULTS
Boys with KS exhibited reduced executive function, as well as lower activation in brain regions subserving executive function, including the inferior frontal gyrus, anterior insula, dorsal anterior cingulate cortex, and caudate nucleus. Secondary analyses indicated that the magnitude of activation differences in boys with KS was associated with severity of pubertal developmental delay, as indexed by lower testosterone (t(36) = 2.285; P = .028) and lower testes volume (t(36) = 2.238; P = .031). Greater parent-reported attention difficulties were additionally associated with lower testicular volume (t(36) = -2.028; P = .050).
CONCLUSION
These findings indicate a neural basis for executive dysfunction in KS and suggest alterations in pubertal development may contribute to increased severity of this cognitive weakness. Future studies that examine whether these patterns change with testosterone replacement therapy are warranted.
Topics: Male; Adolescent; Humans; Child; Klinefelter Syndrome; Brain; Testosterone; Executive Function; Cognitive Dysfunction
PubMed: 37595261
DOI: 10.1210/clinem/dgad487 -
Endocrine Connections Nov 2023Hypogonadism is a clinical syndrome resulting from failure to produce physiological concentrations of sex steroid hormones with accompanying symptoms, such as slowed... (Review)
Review
Hypogonadism is a clinical syndrome resulting from failure to produce physiological concentrations of sex steroid hormones with accompanying symptoms, such as slowed growth and delayed pubertal maturation. Hypogonadism may arise from gonadal disease (primary hypogonadism), dysfunction of the hypothalamic-pituitary axis (secondary hypogonadism) or functional hypogonadism. Disrupted puberty (delayed or absent) leading to hypogonadism can have a significant impact on both the physical and psychosocial well-being of adolescents with lasting effects. The diagnosis of hypogonadism in teenagers can be challenging as the most common cause of delayed puberty in both sexes is self-limited, also known as constitutional delay of growth and puberty (CDGP). Although an underlying congenital cause should always be considered in a teenager with hypogonadism, acquired conditions such as obesity, diabetes mellitus, other chronic diseases and medications have all been associated with low sex steroid hormone levels. In this review, we highlight some forms of functional hypogonadism in adolescents and the clinical challenges to differentiate normal variants from pathological states.
PubMed: 37615381
DOI: 10.1530/EC-23-0190 -
Journal of Developmental and Behavioral... Sep 2023Klinefelter syndrome (KS; 47, XXY), the most common sex chromosome aneuploidy in males, is characterized by testicular failure and testosterone deficiency as well as a...
OBJECTIVE
Klinefelter syndrome (KS; 47, XXY), the most common sex chromosome aneuploidy in males, is characterized by testicular failure and testosterone deficiency as well as a variety of cognitive, social, and emotional challenges. In the current study, we aimed to clarify the cognitive-behavioral profile of peripubertal boys with KS using measures of cognition, academic achievement, adaptive behavior, and quality of life.
METHOD
We compared 47 boys with KS (7-16 years of age) with 55 performance IQ-matched boys without KS on measures of cognition (WISC-V), executive function (BRIEF-2), academic achievement (KTEA-3), adaptive behavior (Vineland-3), and quality of life (PROMIS). In exploratory analyses, we examined associations among these measures and potential associations with pubertal metrics.
RESULTS
Boys with KS demonstrated a significantly different profile of cognition, behavioral ratings of executive function, academic achievement, adaptive behavior, and quality of life compared with their typically developing peers, with, on average, lower functioning. The groups showed significantly different correlations between cognition and aspects of quality of life. No associations were observed between behavior and pubertal development.
CONCLUSION
Taken together, these findings indicated that boys with KS are at increased risk for cognitive difficulties, which may affect academic achievement, adaptive behavior, and quality of life. Although initial exploratory analyses indicated that the magnitude of these alterations was not correlated with severity of testicular failure, longitudinal analyses currently being conducted by our group may help clarify the trajectory of these difficulties through the pubertal transition and testosterone replacement.
Topics: Male; Adolescent; Child; Humans; Academic Success; Klinefelter Syndrome; Quality of Life; Cognition; Adaptation, Psychological; Testosterone
PubMed: 37696031
DOI: 10.1097/DBP.0000000000001201