Triple X syndrome and puberty: focus on the hypothalamus-hypophysis-gonad axis

Central precocious puberty occurring in Bardet‑Biedl syndrome‑10 as a method for self‑protection of human reproductive function: A case report

Hypogonadism and obesity are primary features of Bardet-Biedl syndrome (BBS). Obesity is also an associated factor of central precocious puberty (CPP). The present report describes the case of a girl (age, 7 years and 6 months), with clinical manifestations of precocious puberty, progressive obesity, postaxial polydactyly, retinal degeneration and intellectual disability. The patient visited the clinic for the first time due to early breast development and progressive obesity. After 8 months of follow-up, the bone age had advanced almost 3 years, and the gonadotropin-releasing hormone (GnRH) stimulation test showed results that had changed from indicating pseudo precocious puberty to CPP. Whole-exome gene sequencing showed that there were two heterozygous mutations in the BBS type 10 (BBS10) gene, chr12:76739816(c.1949del) and chr12:76740374(c.1391C>G). The final diagnosis was of BBS10 and CPP. In order to protect the reproductive capacity of the patient, GnRH analogs were used for CPP treatment. After 15 months of treatment and follow-up, a physical examination revealed Tanner breast stage 1. Ultrasonography showed that the uterus and ovaries had reduced to their prepubertal size. In conclusion, the present report describes a case of CPP that occurred in a young girl with BBS10. We hypothesize that this was a prelude to gonad dysplasia, acting as a method for the self-protection of human reproductive function. However, more clinical data and molecular biological evidence are required to confirm the etiology and mechanism of this case.

Ovary-derived circular RNAs profile analysis during the onset of puberty in gilts

Background

In mammals, the ovary is the essential system of female reproduction for the onset of puberty, and the abnormal puberty has negative outcomes on health. CircRNA is a non-coding RNA produced by non-canonical alternative splicing (AS). Several studies have reported that circRNA is involved in the gene regulation and plays an important role in some human diseases. However, the contribution of circRNA has received little known within the onset of puberty in ovary.

Results

Here, the profiles of ovarian circRNAs across pre-, in- and post-pubertal stages were established by RNA-sEq. In total, 972 circRNAs were identified, including 631 stage-specific circRNAs and 8 tissue-specific circRNAs. The biological functions of parental genes of circRNAs were enriched in steroid biosynthesis, autophagy-animal, MAPK signaling pathway, progesterone-mediated oocyte maturation and ras signaling pathway. Moreover, 5 circRNAs derived from 4 puberty-related genes (ESR1, JAK2, NF1 and ARNT) were found in this study. The A3SS events were the most alternative splicing, but IR events were likely to be arose in post-pubertal ovaries. Besides, the circRNA-miRNA-gene networks were explored for 10 differentially expressed circRNAs. Furthermore, the head-to-tail exon as well as the expressions of 10 circRNAs were validated by the divergent RT-qPCR and sanger sequencing.

Conclusions

In summary, the profiles of ovarian circRNAs were provided during pubertal transition in gilts, and these results provided useful information for the investigation on the onset of puberty at the ovarian-circRNAs-level in mammals.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07786-w.

Alternative Splicing Dynamics of the Hypothalamus-Pituitary-Ovary Axis During Pubertal Transition in Gilts

The timing of puberty in mammals marks the point at which reproduction becomes possible. Abnormalities in the timing of puberty may exert a series of negative effects on subsequent health outcomes. Alternative splicing (AS) has not only emerged as a significant factor in the transcription of genes but it is also reported to play a role in the timing of puberty. However, to date, the changes and dynamics of AS during the onset of puberty is extremely seldom explored. In the present study, we used gilts as a research model to investigated the dynamics of AS and differentially expressed AS (DEAS) events within the hypothalamus-pituitary-ovary (HPO) axis across pre-, in-, and post-puberty. We detected 3,390, 6,098, and 9,085 DEAS events in the hypothalamus, pituitary, and ovary when compared across pre-, in-, and post-pubertal stages, respectively. Within the entire HPO axis, we also identified 22,889, 22,857, and 21,055 DEAS events in the pre-, in-, and post-pubertal stages, respectively. Further analysis revealed that the differentially spliced genes (DSGs) associated with staged DEAS events were likely to be enriched in the oxytocin signaling pathway, thyroid hormone signaling pathway, GnRH signaling pathway, and oocyte meiosis signaling pathway. The DSGs associated with DEAS events across the entire HPO axis were enriched in endocytosis signaling pathway, the MAPK signaling pathway, and the Rap1 signaling pathway. Moreover. the ASs of TAC1, TACR3, CYP19A1, ESR1, ESRRA, and FSHR were likely to regulate the functions of the certain HPO tissues during the onset of puberty. Collectively, the AS dynamics and DEAS events were comprehensively profiled in hypothalamus, pituitary, and ovary across the pre-, in-, and post-pubertal stages in pigs. These findings may enhance our knowledge of how puberty is regulated by AS and shed new light on the molecular mechanisms underlying the timing of puberty in mammals.

Diminished Ovarian Reserve in Girls and Adolescents with Trisomy X Syndrome

An extra X chromosome occurs in ~ 1 in 1000 females, resulting in a karyotype 47,XXX also known as trisomy X syndrome (TXS). Women with TXS appear to be at increased risk for premature ovarian insufficiency; however, very little research on this relationship has been conducted. The objective of this case-control study is to compare ovarian function, as measured by anti-mullerian hormone (AMH) levels, between girls with TXS and controls. Serum AMH concentrations were compared between 15 females with TXS (median age 13.4 years) and 26 controls (median age 15.1 years). Females with TXS had significantly lower serum AMH compared to controls (0.7 ng/mL (IQR 0.2-1.7) vs 2.7 (IQR 1.3-4.8), p < 0.001). Additionally, girls with TXS were much more likely to have an AMH below the 2.5th percentile for age with 67% of them meeting these criteria (OR 11, 95% CI 2.3-42). Lower AMH concentrations in females with TXS may represent an increased risk for primary ovarian insufficiency in these patients and potentially a narrow window of opportunity to pursue fertility preservation options. Additional research is needed to understand the natural history of low AMH concentrations and future risk of premature ovarian insufficiency in girls with TXS.

Early neurodevelopmental and medical profile in children with sex chromosome trisomies: Background for the prospective eXtraordinarY babies study to identify early risk factors and targets for intervention

Sex chromosome trisomies (SCT), including Klinefelter syndrome/XXY, Trisomy X, and XYY syndrome, occur in 1 of every 500 births. The past decades of research have resulted in a broadening of known associated medical comorbidities as well as advances in psychological research. This review summarizes what is known about early neurodevelopmental, behavioral, and medical manifestations in young children with SCT. We focus on recent research and unanswered questions related to the risk for neurodevelopmental disorders that commonly present in the first years of life and discuss the medical and endocrine manifestations of SCT at this young age. The increasing rate of prenatal SCT diagnoses provides the opportunity to address gaps in the existing literature in a new birth cohort, leading to development of the eXtraordinarY Babies Study. This study aims to better describe and compare the natural history of SCT conditions, identify predictors of positive and negative outcomes in SCT, evaluate developmental and autism screening measures commonly used in primary care practices for the SCT population, and build a rich data set linked to a bank of biological samples for future study. Results from this study and ongoing international research efforts will inform evidence-based care and improve health and neurodevelopmental outcomes.

Human sex chromosome aneuploidies: The hypothalamic-pituitary-gonadal axis

Sex chromosome aneuploidies (SCA) are relatively common as a group, perhaps 1 per 500 births, but much more common at conception. Many syndromes have been noted in those with these conditions, but not so many data are available concerning the hypothalamic-pituitary-gonadal (HPG) axis. The physiology of the HPG axis is first reviewed at four epochs in time: fetal, birth and mini-puberty, childhood, and adolescence (puberty). Those sections are followed by detailed analysis of the functioning of the HPG axis in individuals with specific SCA with chromosomal numbers ranging from 45 to 49. Robust data are available for the chromosomal complements 47,XXY and 47,XXX with fewer data available for many of the others.

MTHFR C677T polymorphism is associated with follicle-stimulating hormone levels and controlled ovarian hyperstimulation response: a retrospective study from the clinical database

OBJECTIVE

To evaluate the impact of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism with clinical data analysis in controlled ovarian hyperstimulation (COH) of infertile women in the Intravenous Infusion Safety Evaluation Center of Hunan Province, People's Republic of China.

DESIGN

Genetic Association Study.

SETTING

Reproductive medicine clinical.

PATIENT(S)

This genetic association study included 722 infertile women who received the standard long treatment protocol with accessible and complete electronic medical records.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The clinical parameters were obtained from the Intravenous Infusion Safety Evaluation center.

RESULT(S)

Basal FSH levels in the TT group were significantly higher than those of the CC group. The FSH levels after down-regulation in the TT group were higher than those of CC/CT genotypes. The TT genotype patients received significantly higher total doses of GnRH agonist and FSH compared with CC/CT genotypes, whereas the total dose of hCG was higher in the CT genotypes compared with the CC/TT genotypes. Further association analysis between hormone levels and COH outcomes indicated significantly negative correlation of basal FSH levels with antral follicle count and number of oocytes as well as the down-regulation FSH levels with the number of metaphase II oocytes and oocytes.

CONCLUSION(S)

The MTHFR C677T polymorphism was associated with high doses of ovarian stimulation medications, as well as higher FSH levels. The negative correlation between FSH levels and the number of oocytes suggested that C677T polymorphism may play a role in the poor prognosis of COH oocytes. This needs to be studied in future prospective studies with longer follow-up.

Central precocious puberty as a prelude of gonad dysplasia

There is increasing evidence that patients with gonad dysplasia, as characterized by absent or incomplete puberty, can also exhibit central precocious puberty (CPP). Herein, we review the reported cases that manifest with both gonad dysplasia and CPP. Further, we examine the hypothesis that these patients exhibit a normal hypothalamic-pituitary-gonadal axis, hypogonadism, and the presence of residual gonadal function, and that the onset of disease is related to early initiation of the hypothalamic-pituitary-gonadal axis. Thus, we suggest that CPP is a prelude of some partial hypogonadism.

A case report of hypersomnia in tetrasomy X improved with medical therapy

Tetrasomy X is a rare chromosomal anomaly in which sleep disorders have not been previously reported. We report on one patient with tetrasomy X and hypersomnia successfully treated with psychostimulant therapy. Sleep disorders are rarely reported in chromosomal anomalies. Clinicians should screen patients for sleep disorders and manage them appropriately.