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Veterinary Sciences Jun 2024This prospective study investigated the ultrasonographic appearance of the canine testis from birth to adulthood. Eight purpose-bred laboratory Beagle-breed dogs were...
This prospective study investigated the ultrasonographic appearance of the canine testis from birth to adulthood. Eight purpose-bred laboratory Beagle-breed dogs were monitored from 4 to 40 weeks of life. The following parameters were evaluated every two weeks: bodyweight and height, scrotal and testicular volume, ultrasonographically measured testicular volume, echogenicity, heterogeneity, blood-flow score, ratio of the grayscale intensity value of the testis to the capsule, ejaculate volume, motility, viability, and number of spermatozoa. A correlation analysis was carried out between the various measurements obtained. Fertility was achieved in the 36th week of life. The echogenicity of the testicular parenchyma increased with age, and subsequently to the 30th week of life remained constant. The heterogeneity of the testicular parenchyma, as was evaluated by the standard deviation of the values of grayscale intensity of the parenchyma, also increased with age and was >19 at the onset of fertility. The ratio of grayscale intensity of testicular parenchyma had values < 200 at maturity. A colour Doppler evaluation first detected blood flow in the testis in the 22nd week. After the 32nd week, distinct signals were visible. In the 36th week, >80% of the testes imaged had visible vessels. A significant correlation was found between all the evaluation methods. The findings of the study may help clinicians detect the onset of fertility in dogs, especially when semen evaluation is not feasible; however, their applicability in all breeds or individuals might possibly vary due to genetic, physiological, and developmental differences. In summary, the study ultrasonographically explores the testicular maturity in dogs, with the aim to improve clinical assessments and health management in these animals.
PubMed: 38922017
DOI: 10.3390/vetsci11060270 -
Current Issues in Molecular Biology May 2024Sexual maturation of Atlantic salmon males is marked by dramatic endocrine changes and rapid growth of the testes, resulting in an increase in the gonad somatic index...
Sexual maturation of Atlantic salmon males is marked by dramatic endocrine changes and rapid growth of the testes, resulting in an increase in the gonad somatic index (GSI). We examined the association of gonadal growth with serum sex steroids, as well as pituitary and testicular gene expression levels, which were assessed with a DNA oligonucleotide microarray. The testes transcriptome was stable in males with a GSI < 0.08% despite the large difference between the smallest and the largest gonads. Fish with a GSI ≥ 0.23% had 7-17 times higher serum levels of five male steroids and a 2-fold increase in progesterone, without a change in cortisol and related steroids. The pituitary transcriptome showed an upregulation of the hormone-coding genes that control reproduction and behavior, and structural rearrangement was indicated by the genes involved in synaptic transmission and the differentiation of neurons. The observed changes in the abundance of testicular transcripts were caused by the regulation of transcription and/or disproportional growth, with a greater increase in the germinative compartment. As these factors could not be separated, the transcriptome results are presented as higher or lower specific activities (HSA and LSA). LSA was observed in 4268 genes, including many genes involved in various immune responses and developmental processes. LSA also included genes with roles in female reproduction, germinal cell maintenance and gonad development, responses to endocrine and neural regulation, and the biosynthesis of sex steroids. Two functional groups prevailed among HSA: structure and activity of the cilia (95 genes) and meiosis (34 genes). The puberty of A. salmon testis is marked by the predominance of spermatogenesis, which displaces other processes; masculinization; and the weakening of external regulation. Results confirmed the known roles of many genes involved in reproduction and pointed to uncharacterized genes that deserve attention as possible regulators of sexual maturation.
PubMed: 38920991
DOI: 10.3390/cimb46060319 -
Current Oncology (Toronto, Ont.) May 2024Ovarian transposition (OT) has been proposed as a protective measure against radiation-induced damage to ovarian function and fertility. Despite its historical use,... (Observational Study)
Observational Study
Ovarian transposition (OT) has been proposed as a protective measure against radiation-induced damage to ovarian function and fertility. Despite its historical use, limited research has focused on evaluating endocrine and exocrine ovarian function after OT performed in adolescents and young adults (AYAs) before or during puberty. The purpose of our study was to investigate the fertility, pubertal development, and ovarian function of women with a previous history of OT during childhood, adolescence or young adulthood. In an observational bicentric retrospective study, we included 32 young female cancer patients who underwent OT before the age of 26 between 1990 and 2015 at Lyon Léon Bérard Cancer Center or Nancy University Hospital. The mean age at the time of OT was 15.6 years with a cancer diagnosis at 15 ± 4.8 years. Among the 10 women attempting pregnancy post-treatment, 60% achieved successful pregnancies. After a mean follow-up of 9.6 ± 7 years, 74% (17 out of 23) of women recovered spontaneous menstrual cycles (seven out of eight evaluable women with OT before or during puberty). Notably, 35% of women who did not attempt pregnancy demonstrated adequate ovarian reserve. Ovarian reserve and function recovery were influenced by the specific chemotherapy received. Importantly, our findings suggest that OT's effectiveness on ovarian activity resumption does not significantly differ when performed before or during puberty compared to pubertal stages. This study contributes valuable insights into the long-term reproductive outcomes of young women undergoing OT, emphasizing its potential efficacy in preserving ovarian function and fertility across different developmental stages.
Topics: Humans; Female; Adolescent; Ovary; Young Adult; Neoplasms; Retrospective Studies; Fertility Preservation; Adult; Child; Fertility; Ovarian Reserve
PubMed: 38920724
DOI: 10.3390/curroncol31060240 -
The Journal of Clinical Endocrinology... Jun 2024To describe the natural history of inhibin B throughout life according to sex, age, and pubertal development.
OBJECTIVE
To describe the natural history of inhibin B throughout life according to sex, age, and pubertal development.
METHODS
Based on serum samples from 2707 healthy controls aged 0 to 80 years, sex- and age-specific reference ranges of inhibin B concentrations were constructed. Concentrations were evaluated according to pubertal development and use of oral contraceptives (OCs). Also, measurements from 42 patients with Klinefelter syndrome were included.
RESULTS
In both sexes, inhibin B concentrations were high during minipuberty, decreased in childhood, and increased significantly from Tanner stages B1 to B3 (peak: B4) in females and from G1 to G3 (peak: G3) in males. Despite variations in menstruating females, inhibin B concentrations remained relatively constant after puberty, until becoming unmeasurable at menopause. Despite a modest decrease, the inhibin B concentration in males remained relatively high from puberty onwards. At any age, males had highest concentrations. Inhibin B standard deviation (SD) scores were lower in OC-users (median SD score = -0.88) than in non-users (SD score = 0.35), p < 0.001. In patients with Klinefelter syndrome, inhibin B concentrations spanned the reference range until around 15 years of age, where they decreased to subnormal or unmeasurable levels.
CONCLUSION
Valuable sex- and age-specific reference data for inhibin B concentrations were provided. In OC-users, decreased concentrations of inhibin B underlined the ovaries as the only place of inhibin B production. In patients with Klinefelter syndrome, the decline in inhibin B concentrations at puberty underlined the shift in regulation of inhibin B production at pubertal onset.
PubMed: 38920271
DOI: 10.1210/clinem/dgae439 -
Animal Reproduction Science Jun 2024Climate change has been linked to increasing temperatures and weather extremes. Certain regions around the world become more susceptible to environmental hazards that... (Review)
Review
Climate change has been linked to increasing temperatures and weather extremes. Certain regions around the world become more susceptible to environmental hazards that limit pig production and reproductive fertility. Environmental measures that link to pig fertility are needed to assess change, risk and develop solutions. Sub-populations of pigs display lower fertility in summer and are susceptible to heat stress. In the context of a warming climate, elevated temperatures and number of heat stress days increase body temperature and change the physiology, behavior, feed intake, and stress response of the pig. These changes could alter follicle development, oocyte quality, estrus expression, conception and litter size. In boars, sperm quality and production are reduced in response to summer heat stress. Nevertheless, while temperature increases have occurred over the years in some warmer locations, other regions have not shown those changes. Perhaps this involves the measures used for heat stress assessment or that climate is buffered in more temperate areas. Reductions in pig fertility are not always evident, and depend upon climate, year, genotype and management. This could also involve selection, as females more susceptible to heat stress and fertility failure, are subsequently culled. In the years from 1999 to 2020 when increases in global temperature from baseline occurred, measures of female fertility improved for farrowing rate and litter size. Progressive reduction in fertility may not be apparent in all geo-locations, but as temperatures increases become more widespread, these changes are likely to become more obvious and detectable.
PubMed: 38918086
DOI: 10.1016/j.anireprosci.2024.107537 -
Journal of Mammary Gland Biology and... Jun 2024Conflicting data exist as to how mammary epithelial cell proliferation changes during the reproductive cycle. To study the effect of endogenous hormone fluctuations on...
Conflicting data exist as to how mammary epithelial cell proliferation changes during the reproductive cycle. To study the effect of endogenous hormone fluctuations on gene expression in the mouse mammary gland, we performed bulk RNAseq analyses of epithelial and stromal cell populations that were isolated either during puberty or at different stages of the adult virgin estrous cycle. Our data confirm prior findings that proliferative changes do not occur in every mouse in every cycle. We also show that during the estrous cycle the main gene expression changes occur in adipocytes and fibroblasts. Finally, we present a comprehensive overview of the Wnt gene expression landscape in different mammary gland cell types in pubertal and adult mice. This work contributes to understanding the effects of physiological hormone fluctuations and locally produced signaling molecules on gene expression changes in the mammary gland during the reproductive cycle and should be a useful resource for future studies investigating gene expression patterns in different cell types across different developmental timepoints.
Topics: Animals; Female; Mice; Mammary Glands, Animal; Stromal Cells; Epithelial Cells; Transcriptome; Gene Expression Profiling; Sexual Maturation; Cell Proliferation; Estrous Cycle
PubMed: 38916673
DOI: 10.1007/s10911-024-09565-1 -
BioRxiv : the Preprint Server For... Jun 2024Many transgender youth seek gender affirming care, such as puberty suppression, to prolong decision-making and to align their physical sex characteristics with their...
UNLABELLED
Many transgender youth seek gender affirming care, such as puberty suppression, to prolong decision-making and to align their physical sex characteristics with their gender identity. During peripubertal growth, connective tissues such as tendon rapidly adapt to applied mechanical loads (e.g., exercise) yet if and how tendon adaptation is influenced by sex and gender affirming hormone therapy during growth remains unknown. The goal of this study was to understand the how pubertal suppression influences the structural and functional properties of the Achilles tendon using an established mouse model of transmasculine gender affirming hormone therapy. C57BL/6N female-born mice were assigned to experimental groups to mimic gender-affirming hormone therapy in human adolescents, and treatment was initiated prior to the onset of puberty (at postnatal day 26, P26). Experimental groups included controls and mice serially treated with gonadotropin release hormone analogue (GnRHa), delayed Testosterone (T), or GnRHa followed by T. We found that puberty suppression using GnRHa, with and without T, improved the overall tendon load capacity in female-born mice. Treatment with T resulted in an increase in the maximum load that tendon can withstand before failure. Additionally, we found that GnRHa, but not T, treatment resulted in a significant increase in cell density at the Achilles enthesis.
NEW & NOTEWORTHY
These findings demonstrate that puberty suppression or testosterone does not negatively influence tendon structural or functional properties in a mouse model of transmasculine gender affirming care. In all treatment groups, the ability of the tendon to withstand load was significantly increased. Puberty suppression with GnRHa significantly increased enthesis cell density, suggesting an extended growth phase. These findings elucidate the effects of gender affirming care on the structural and functional properties of the tendon and enthesis.
PubMed: 38915724
DOI: 10.1101/2024.06.10.598308 -
BioRxiv : the Preprint Server For... Jun 2024Postnatal genomic regulation significantly influences tissue and organ maturation but is under-studied relative to existing genomic catalogs of adult tissues or prenatal...
Postnatal genomic regulation significantly influences tissue and organ maturation but is under-studied relative to existing genomic catalogs of adult tissues or prenatal development in mouse. The ENCODE4 consortium generated the first comprehensive single-nucleus resource of postnatal regulatory events across a diverse set of mouse tissues. The collection spans seven postnatal time points, mirroring human development from childhood to adulthood, and encompasses five core tissues. We identified 30 cell types, further subdivided into 69 subtypes and cell states across adrenal gland, left cerebral cortex, hippocampus, heart, and gastrocnemius muscle. Our annotations cover both known and novel cell differentiation dynamics ranging from early hippocampal neurogenesis to a new sex-specific adrenal gland population during puberty. We used an ensemble Latent Dirichlet Allocation strategy with a curated vocabulary of 2,701 regulatory genes to identify regulatory "topics," each of which is a gene vector, linked to cell type differentiation, subtype specialization, and transitions between cell states. We find recurrent regulatory topics in tissue-resident macrophages, neural cell types, endothelial cells across multiple tissues, and cycling cells of the adrenal gland and heart. Cell-type-specific topics are enriched in transcription factors and microRNA host genes, while chromatin regulators dominate mitosis topics. Corresponding chromatin accessibility data reveal dynamic and sex-specific regulatory elements, with enriched motifs matching transcription factors in regulatory topics. Together, these analyses identify both tissue-specific and common regulatory programs in postnatal development across multiple tissues through the lens of the factors regulating transcription.
PubMed: 38915583
DOI: 10.1101/2024.06.12.598567 -
Journal of Clinical Research in... Jun 2024Delayed puberty is thought to be common in boys with Duchenne muscular dystrophy (DMD) treated with long term oral glucocorticoid. This study aims to report the...
BACKGROUND
Delayed puberty is thought to be common in boys with Duchenne muscular dystrophy (DMD) treated with long term oral glucocorticoid. This study aims to report the frequency of delayed puberty in DMD from examination by a paediatric endocrinologist alongside detailed endocrine investigations.
METHODS
All boys with DMD aged at least 14 years in January 2022 known to the paediatric neuromuscular service (2016-2022) were included in this study. Delayed puberty was defined based on testicular volume and genital staging in comparison to published puberty nomogram.
RESULTS
Twenty-four out of 37 boys (65%) had evidence of delayed puberty, 23/24 (96%) of those with delayed puberty were on glucocorticoid therapy all of whom were on daily glucocorticoid. On the other hand, 7/13 (54%) of those with normal timing of puberty were on glucocorticoid; 2/7 (29%) were on the intermittent regimen. Of those who were on daily glucocorticoid therapy at the time of assessment of puberty, 23/28 (82%) had evidence of delayed puberty. In boys with delayed puberty, endocrine investigations showed low luteinizing hormone (LH) with undetectable testosterone levels, a pre-pubertal response with lutenizing hormone releasing hormone test and sub-optimal testosterone levels with prolonged human chorionic gonadotropin stimulation.
CONCLUSION
The frequency of delayed puberty in boys with DMD was 65%. Eighty-two percent of adolescent boys with DMD on daily glucocorticoid had evidence of delayed puberty. Biochemical investigations point to functional central hypogonadism in these adolescents. Our data supports the routine monitoring of puberty in boys with DMD.
PubMed: 38915199
DOI: 10.4274/jcrpe.galenos.2024.2024-2-18 -
Seminars in Reproductive Medicine Jun 2024Anti-Müllerian hormone (AMH) is secreted by Sertoli cells and is responsible for the regression of Müllerian ducts in the male fetus as part of the sexual...
Anti-Müllerian hormone (AMH) is secreted by Sertoli cells and is responsible for the regression of Müllerian ducts in the male fetus as part of the sexual differentiation process. Serum AMH concentrations are at their lowest levels in the first days after birth but increase after the first week, likely reflecting active Sertoli cell proliferation. AMH rises rapidly in concentration in boys during the first month, reaching a peak level at ∼6 months of age, and it remains high during childhood, then they will slowly decline during puberty, falling to low levels in adulthood. Serum AMH measurement is used by pediatric endocrinologist as a specific marker of immature Sertoli cell number and function during childhood. After puberty, AMH is released especially by the apical pole of the Sertoli cells toward the lumen of the seminiferous tubules, resulting in higher levels in the seminal plasma than in the serum. Recently, AMH has received increasing attention in research on male fertility-related disorders. This article reviews and summarizes the potential contribution of serum AMH measurement in different male fertility-related disorders.
PubMed: 38914117
DOI: 10.1055/s-0044-1787687