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Proceedings of the National Academy of... Jun 2024Germ cells are regulated by local microenvironments (niches), which secrete instructive cues. Conserved developmental signaling molecules act as niche-derived regulatory...
Germ cells are regulated by local microenvironments (niches), which secrete instructive cues. Conserved developmental signaling molecules act as niche-derived regulatory factors, yet other types of niche signals remain to be identified. Single-cell RNA-sequencing of sexual planarians revealed niche cells expressing a nonribosomal peptide synthetase (). Inhibiting led to loss of female reproductive organs and testis hyperplasia. Mass spectrometry detected the dipeptide β-alanyl-tryptamine (BATT), which is associated with reproductive system development and requires and a monoamine-transmitter-synthetic enzyme Aromatic L-amino acid decarboxylase (AADC) for its production. Exogenous BATT rescued the reproductive defects after or inhibition, restoring fertility. Thus, a nonribosomal, monoamine-derived peptide provided by niche cells acts as a critical signal to trigger planarian reproductive development. These findings reveal an unexpected function for monoamines in niche-germ cell signaling. Furthermore, given the recently reported role for BATT as a male-derived factor required for reproductive maturation of female schistosomes, these results have important implications for the evolution of parasitic flatworms and suggest a potential role for nonribosomal peptides as signaling molecules in other organisms.
Topics: Animals; Planarians; Female; Male; Peptide Synthases; Sexual Development; Peptides; Reproduction; Signal Transduction
PubMed: 38889152
DOI: 10.1073/pnas.2321349121 -
Journal of Fish Biology Jun 2024Sexual dimorphisms are generated by divergent processes, such as natural or sexual selection and niche convergence. Males and females of the lesser guitarfish, Zapteryx...
Sexual dimorphisms are generated by divergent processes, such as natural or sexual selection and niche convergence. Males and females of the lesser guitarfish, Zapteryx brevirostris, present morphological differences in their discs, and the relationships with the species biology and ecology were unrecognized. Analysing the morphometry of 201 specimens and the influence of bottom features on the frequencies of 188 specimens among life stages and sexes, we found strong evidence that gonadal maturation leads to dimorphisms on discs, validating a concavity on male pectoral fins as a secondary sexual dimorphism and rejecting the hypothesis that such dimorphisms were related to ecological pressures. The principal component analysis (PCA) and permutational MANOVA (PERMANOVA) analyses revealed that males and females shared similar body aspects until they reached maturity, mainly due to lower variations in W, W, L, D, and L at younger life stages. The relationships of these variables with L corroborate the former results, showing a changing point around L > 30 cm where females started to attain larger measurements than males. Moreover, we revealed ontogenetic shifts, with adults from both sexes exploring different habitats than juveniles and subadults. Differences in frequencies of each life stage were best explained by organic matter (OM) with the adults exploring bottom habitats of higher concentrations of OM than juveniles and subadults, strengthening the assumption that body differences between sexes are not related to ecological pressures. These results bring not only new insights about the possible advantages that those morphometric differences provide to males while mating but also information about the abiotic influences on species distribution, which, along with knowledge of local oceanographic dynamics and benthic community patterns, would inform actions for species conservation.
PubMed: 38880934
DOI: 10.1111/jfb.15833 -
Molecular Ecology Jun 2024Linking reproductive fitness with adaptive traits at the genomic level can shed light on the mechanisms that produce and maintain sex-specific selection. Here, we...
Linking reproductive fitness with adaptive traits at the genomic level can shed light on the mechanisms that produce and maintain sex-specific selection. Here, we construct a multigenerational pedigree to investigate sex-specific selection on a maturation gene, vgll3, in a wild Atlantic salmon population. The vgll3 locus is responsible for ~40% of the variation in maturation (sea age at first reproduction). Genetic parentage analysis was conducted on 18,265 juveniles (parr) and 685 adults collected at the same spawning ground over eight consecutive years. A high proportion of females (26%) were iteroparous and reproduced two to four times in their lifetime. A smaller proportion of males (9%) spawned at least twice in their lifetime. Sex-specific patterns of reproductive fitness were related to vgll3 genotype. Females showed a pattern of overdominance where vgll3*EL genotypes had three-fold more total offspring than homozygous females. In contrast, males demonstrated that late-maturing vgll3*LL individuals had two-fold more offspring than either vgll3*EE or vgll3*EL males. Taken together, these data suggest that balancing selection in females contributes to the maintenance of variation at this locus via increased fitness of iteroparous vgll3*EL females. This study demonstrates the utility of multigenerational pedigrees for uncovering complex patterns of reproduction, sex-specific selection and the maintenance of genetic variation.
PubMed: 38877757
DOI: 10.1111/mec.17435 -
Cureus May 2024Pituitary stalk interruption syndrome is a triad of thin (<1 mm) or complete absence of the pituitary stalk with either an aplastic or ectopic posterior lobe of the...
Pituitary stalk interruption syndrome is a triad of thin (<1 mm) or complete absence of the pituitary stalk with either an aplastic or ectopic posterior lobe of the pituitary gland and a hypoplastic or absent anterior lobe of the pituitary. Patients present with growth retardation, short height, seizures, intellectual disability, and absence of sexual maturation at the expected time. Here, we presented a case of a 12-year-old male with stunted growth. Upon examination, there was reduced height, more than 3 standard deviations below the average for his chronological age. Laboratory results showed reduced levels of growth hormone and thyrotropin. Dual-energy X-ray absorptiometry revealed osteoporosis, while an X-ray of the wrist for bone age corresponded to seven years. MRI imaging confirmed the classical triad of findings for pituitary stalk interruption syndrome. Consequently, the patient was referred back to the endocrinology clinic for further management.
PubMed: 38872685
DOI: 10.7759/cureus.60232 -
Journal of Sports Sciences May 2024The purpose of this study was to analyse secular trend in handgrip strength (HGS) in adolescents using an allometric approach and identify the factors associated. The...
The purpose of this study was to analyse secular trend in handgrip strength (HGS) in adolescents using an allometric approach and identify the factors associated. The sample comprised 657 and 1004 adolescents (14 to 19 years) in 2007 and 2017/2018, respectively, of public schools in Florianópolis, Brazil. The dependent variable was HGS normalised to body mass and height. Covariance analysis was used to examine secular trends in HGS, and multiple linear regression was used to identify associated factors. The independent variables were sociodemographic, biological, and behavioural factors. Comparison of HGS between surveys indicated a negative secular trend in both sexes ( < 0.001). In boys, there was a positive association of HGS with age and FFM in both surveys. In 2017/18, there was a positive association with sexual maturation and a negative association with sitting time and fat percentage. In girls, FFM was positively associated with HGS in both surveys. In 2007, there were positive associations of HGS with age and vigorous physical activity, whereas, in 2017/18, negative associations were observed with economic level and sitting time. The findings of the present study show a decline in adolescent HGS. And behavioural changes appear to be contributing to declines in HGS.
Topics: Humans; Adolescent; Male; Hand Strength; Female; Brazil; Young Adult; Exercise; Sexual Maturation; Age Factors; Sex Factors; Sitting Position; Sociodemographic Factors; Cross-Sectional Studies; Socioeconomic Factors; Body Mass Index; Sedentary Behavior
PubMed: 38869478
DOI: 10.1080/02640414.2024.2364137 -
Endocrine Reviews Jun 2024Mouse models of growth hormone deficiency (GHD) have provided important tools for uncovering the various actions of GH. Nearly 100 years of research using these mouse...
Mouse models of growth hormone deficiency (GHD) have provided important tools for uncovering the various actions of GH. Nearly 100 years of research using these mouse lines has greatly enhanced our knowledge of the GH/IGF-1 axis. Some of the shared phenotypes of the five "common" mouse models of GHD include reduced body size, delayed sexual maturation, decreased fertility, reduced muscle mass, increased adiposity, and enhanced insulin sensitivity. Since these common mouse lines outlive their normal-sized littermates - and have protection from age-associated disease - they have become important fixtures in the aging field. On the other hand, the twelve "uncommon" mouse models of GHD described herein have tremendously divergent health outcomes ranging from beneficial aging phenotypes (similar to those described for the common models) to extremely detrimental features (such as improper development of the CNS, numerous sensory organ defects, and embryonic lethality). Moreover, advancements in next generation sequencing technologies have led to the identification of an expanding array of genes that are recognized as causative agents to numerous rare syndromes with concomitant GHD. Accordingly, this review provides researchers with a comprehensive up-to-date collection of the common and uncommon mouse models of GHD that have been used to study various aspects of physiology and metabolism associated with multiple forms of GHD. For each mouse line presented, the closest comparable human syndromes are discussed providing important parallels to the clinic.
PubMed: 38853618
DOI: 10.1210/endrev/bnae017 -
Hormone Research in Paediatrics Jun 2024Normal hypothalamic-pituitary-ovarian (HPO) endocrine function is essential for female pubertal and psychosocial development and for ongoing adult physical, sexual and... (Review)
Review
BACKGROUND
Normal hypothalamic-pituitary-ovarian (HPO) endocrine function is essential for female pubertal and psychosocial development and for ongoing adult physical, sexual and psychosocial health. Girls with hypogonadism, any endocrine disorder causing abnormal uterine bleeding (AUB) or with contraception needs may require sex hormone treatment. Challenges include evolving needs of a young girl through the course of sexual maturation, potential health risks related to the use of sex hormones for pubertal induction, hormone replacement therapy (HRT), menstrual management and/or contraception.
SUMMARY
To ensure optimal sex hormone treatment, both a comprehensive understanding of the underlying disorder affecting HPO endocrine function and a professional communication with the patient and physicians involved are warranted. In this narrative mini-review, we discuss pubertal induction and HRT for girls with hypogonadism and the management of AUB and contraception for young women up to age 30 years. Additionally, we provide advice on management of AUB and contraception in young women with common conditions including polycystic ovary syndrome, congenital adrenal hyperplasia and others. A PubMed-literature search including articles published over the last 20 years, together with clinical experience of the authors was integrated to provide treatment recommendations.
KEY MESSAGE
Sex hormone treatment, where needed, requires comprehensive understanding of a range of available options. When tailored to individual needs, with flexibility to accommodate changing circumstance in young women it is safe, well tolerated and provides both physical and psychosocial health.
PubMed: 38852580
DOI: 10.1159/000539697 -
Post Reproductive Health Jun 2024Genitourinary syndrome of menopause (GSM) is a common condition, yet there is no defined, objective, and reproducible intervention with which to make a diagnosis. There...
BACKGROUND
Genitourinary syndrome of menopause (GSM) is a common condition, yet there is no defined, objective, and reproducible intervention with which to make a diagnosis. There are many different treatment options available, but without the correct diagnosis, affected women are unable to access the right therapy. This paper reports on the questionnaire arm of the VAN study (VAginal ) which aimed to evaluate the performance and acceptability of the methods of assessment of GSM, described below.
OBJECTIVES
To determine the value of the Day-to-Day Impact of Vaginal Aging (DIVA) questionnaire: a multidimensional measure of the impact of vaginal symptoms on functioning and well-being in postmenopausal women, in a prospective, observational, feasibility study.
METHODS
60 women were recruited to the study (20 premenopausal, asymptomatic women (control group) and 40 peri- and postmenopausal, symptomatic women). All women had a baseline assessment, using three different interventions, in addition to the DIVA questionnaire and symptomatic women were offered treatment, followed by a second assessment undertaken at 16 weeks, using the same interventions. This paper focusses on the outcomes for the questionnaire and specifically on the paired data sets, before and after treatment.
RESULTS
An improvement in the score for all four sections of DIVA (Activities of daily living, Emotions, Sexual Activity, and Feelings about yourself and your body (female embodiment)) was observed, following any treatment. Additional questions were added to DIVA, to assess patient preference in relation to the different diagnostic interventions. These included a speculum examination as part of the clinical assessment, a smear taken from the lateral vaginal wall to assess the vaginal maturation index, both undertaken by a clinician and a self-administered tampon to collect vaginal secretions, to determine the small molecule metabolite profile, using NMR spectroscopy, and to enable analysis of the vaginal microbiome. The medical standard tampon was the preferred intervention, before and after treatment, for women eligible for treatment.
CONCLUSION
The VAN study demonstrates that DIVA, a previously tested questionnaire, is an easily accessible intervention, to assess the impact of urogenital symptoms on quality-of-life indicators in women in the United Kingdom with GSM and that women prefer to use a tampon themselves, rather than have a clinician performed vaginal speculum examination or a vaginal smear.
PubMed: 38842127
DOI: 10.1177/20533691241246366 -
The American Journal of Clinical... Jun 2024The World Health Organization recommends calcium supplementation (1500-2000 mg/d) during pregnancy for women with a low-calcium intake. (Randomized Controlled Trial)
Randomized Controlled Trial
Effects of maternal calcium supplementation on offspring blood pressure and growth in childhood and adolescence in a population with a low-calcium intake: follow-up study of a randomized controlled trial.
BACKGROUND
The World Health Organization recommends calcium supplementation (1500-2000 mg/d) during pregnancy for women with a low-calcium intake.
OBJECTIVES
The purpose of this study was to investigate whether pregnancy calcium supplementation affects offspring blood pressure and growth in The Gambia where calcium intakes are low (300-400 mg/d).
METHODS
Follow-up of offspring born during a randomized controlled trial of pregnancy calcium supplementation (ISRCTN96502494, 1996-2000) in which mothers were randomly assigned to 1500 mg Ca/d (Ca) or placebo (P) from 20 wk pregnancy to delivery. Offspring were enrolled at age 3 y in studies where blood pressure and anthropometry were measured under standardized conditions at approximately 2-yearly intervals. Mean blood pressure and growth curves were fitted for females and males separately, using the longitudinal SuperImposition by Translation and Rotation (SITAR) mixed effects model. This generates 3 individual-specific random effects: size, timing, and intensity, reflecting differences in size, age at peak velocity, and peak velocity through puberty relative to the mean curve, respectively.
RESULTS
Five hundred twenty-three singleton infants were born during the trial (maternal group assignment: Ca/P = 259/264). Four hundred ninety-one were enrolled as children (females: F-Ca/F-P = 122/129 and males: M-Ca/M-P = 119/121) and measured regularly from 3.0 y to mean age 18.4 y; 90% were measured on ≥8 occasions. SITAR revealed differences in the systolic blood pressure and height curves between pregnancy supplement groups in females, but not in males. F-Ca had lower systolic blood pressure than F-P at all ages (size = -2.1 ± SE 0.8 mmHg; P = 0.005) and lower peak height velocity (intensity = -2.9 ± SE 1.1%, P = 0.009). No significant pregnancy supplement effects were seen for other measures.
CONCLUSIONS
This study showed, in female offspring, that pregnancy calcium supplementation may lower systolic blood pressure and slow linear growth in childhood and adolescence, adding to evidence of offspring sexual dimorphism in responses to maternal supplementation. Further research is warranted on the long-term and intergenerational effects of antenatal supplementations. This trial was registered at ISRCTN Registry as ISRCTN96502494.
Topics: Humans; Female; Pregnancy; Male; Dietary Supplements; Blood Pressure; Calcium, Dietary; Follow-Up Studies; Child, Preschool; Adolescent; Gambia; Maternal Nutritional Physiological Phenomena; Adult; Child; Child Development; Prenatal Exposure Delayed Effects; Body Height
PubMed: 38839195
DOI: 10.1016/j.ajcnut.2024.02.025 -
Nature Plants Jun 2024In bryophytes, sexual reproduction necessitates the release of motile sperm cells from a gametophyte into the environment. Since 1856, this process, particularly in...
In bryophytes, sexual reproduction necessitates the release of motile sperm cells from a gametophyte into the environment. Since 1856, this process, particularly in liverworts, has been known to depend on water. However, the molecular mechanism underlying this phenomenon has remained elusive. Here we identify the plasma membrane protein MpMLO1 in Marchantia polymorpha, a model liverwort, as critical for sperm discharge from antheridia. The MpMLO1-expressing tip cells among the sperm-wrapping jacket cells undergo programmed cell death upon antheridium maturation to facilitate sperm discharge after the application of water and even hypertonic solutions. The absence of MpMLO1 leads to reduced cytoplasmic Ca levels in tip cells, preventing cell death and consequently sperm discharge. Our findings reveal that MpMLO1-mediated programmed cell death in antheridial tip cells, regulated by cytosolic Ca dynamics, is essential for sperm release, elucidating a key mechanism in bryophyte sexual reproduction and providing insights into terrestrial plant evolution.
Topics: Marchantia; Plant Proteins; Calcium; Reproduction; Hepatophyta; Apoptosis
PubMed: 38831045
DOI: 10.1038/s41477-024-01703-1