Integrated multicomponent analysis based on ultra-high-performance liquid chromatography coupled with quadrupole-Exactive Orbitrap mass spectrometry and network pharmacology to elucidate the effective constituents and potential mechanism of Zhibai Dihuang pill in treating childhood precocious puberty.

RATIONALE: Childhood precocious puberty (CPP) is a common pediatric endocrine disorder with significant associated risks. Zhibai Dihuang pill (ZBDHP), a classic recipe of the Qing dynasty with its efficacy of nourishing yin and clearing heat, can downregulate the expression of ESR1 in the uterus and ovaries, thereby inhibiting CPP. However, as of now, the main active ingredients and pharmacological mechanisms of ZBDHP remain unclear. METHODS: A comprehensive approach was proposed using ultra-high-performance liquid chromatography coupled with quadrupole-Exactive Orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap-MS) and network pharmacology to explore the potentially active constituents of ZBDHP and reveal the underlying mechanisms against CPP. Molecular docking was used to verify the possible mechanisms. RESULTS: A total of 214 constituents derived were identified via UHPLC-Q-Exactive Orbitrap-MS, and 12 of them were definitely characterized using reference standards. Subsequently, compounds tetrahydropalmatine, alisol C, 25-anhydroalisol A 11-acetate, hispidone, cavidine, alisol E, melianone, neogitogenin, denudatin B, and 16ß-hydroperoxyalisol B with related targets PIK3CA, HSD11B1, CYP19A1, AR, PTGS2, CDK2, NR3C1, MMP2, MMP1, and MAPK1 were regarded as key components and targets for ZBDHP treating CPP using the compound-target-pathway network. Besides, the results revealed that the pathways conduced obviously to therapeutic efficacy, including pathways in cancer, neuroactive ligand-receptor interaction, and cyclic adenosine monophosphate（cAMP） signaling pathways. Molecular docking indicated that PIK3CA, HSD11B1, and CYP19A1 exhibited high affinities to corresponding compounds. Overall, the study determined the multicomponent, multitarget, and multipathway mechanisms of ZBDHP against CPP. CONCLUSIONS: This study provided a new method for exploring the chemical constituents and pharmacology mechanism of traditional Chinese medicine.

MKRN3-mediated ubiquitination of Poly(A)-binding proteins modulates the stability and translation of GNRH1 mRNA in mammalian puberty.

The family of Poly(A)-binding proteins (PABPs) regulates the stability and translation of messenger RNAs (mRNAs). Here we reported that the three members of PABPs, including PABPC1, PABPC3 and PABPC4, were identified as novel substrates for MKRN3, whose deletion or loss-of-function mutations were genetically associated with human central precocious puberty (CPP). MKRN3-mediated ubiquitination was found to attenuate the binding of PABPs to the poly(A) tails of mRNA, which led to shortened poly(A) tail-length of GNRH1 mRNA and compromised the formation of translation initiation complex (TIC). Recently, we have shown that MKRN3 epigenetically regulates the transcription of GNRH1 through conjugating poly-Ub chains onto methyl-DNA bind protein 3 (MBD3). Therefore, MKRN3-mediated ubiquitin signalling could control both transcriptional and post-transcriptional switches of mammalian puberty initiation. While identifying MKRN3 as a novel tissue-specific translational regulator, our work also provided new mechanistic insights into the etiology of MKRN3 dysfunction-associated human CPP.

Relationship between Body Mass Index and Bone Turnover Markers in Girls with Idiopathic Central Precocious Puberty.

Background: This study aimed to determine the effect of body mass index (BMI) on bone turnover markers in girls with idiopathic central precocious puberty (ICPP) according to weight status at diagnosis. Methods: Two hundred and eleven girls with ICPP were divided according to their weight status at diagnosis into three groups: normal weight, overweight, and obese. The serum levels of total procollagen type 1 N-terminal propeptide (P1NP), N-terminal midfragment of osteocalcin, ß-C-terminal telopeptide of type 1 collagen, and some biochemical indicators were measured. Associations between variables were evaluated by multiple regression analysis. Results: Serum P1NP concentrations were significantly different among groups (p < 0.001). No other significant differences were noted in N-terminal midfragment of osteocalcin and ß-C-terminal telopeptide of type 1 collagen. BMI was associated with estradiol (r = 0.155, p < 0.05) and inversely associated with P1NP (r = -0.251, p < 0.01), luteinizing hormone peak (r = -0.334, p < 0.01), follicle-stimulating hormone peak (r = -0.215, p < 0.01), and luteinizing hormone/follicle-stimulating hormone peak (r = -0.284, p < 0.01). Multiple regression analysis of factors associated with BMI showed that it was correlated with P1NP, follicle-stimulating hormone base, and luteinizing hormone peak in the overweight group and the obese group. Conclusions: Our findings showed that BMI was associated with P1NP, revealing the reduction of bone formation in overweight and obese girls with ICPP. During the diagnosis and treatment of girls with ICPP, attention should be paid to body weight and bone metabolism.

A Putative Adverse Outcome Pathway Network for Disrupted Female Pubertal Onset to Improve Testing and Regulation of Endocrine Disrupting Chemicals.

The average age for pubertal onset in girls has declined over recent decades. Epidemiological studies in humans and experimental studies in animals suggest a causal role for endocrine disrupting chemicals (EDCs) that are present in our environment. Of concern, current testing and screening regimens are inadequate in identifying EDCs that may affect pubertal maturation, not least because they do not consider early-life exposure. Also, the causal relationship between EDC exposure and pubertal timing is still a matter of debate. To address this issue, we have used current knowledge to elaborate a network of putative adverse outcome pathways (pAOPs) to identify how chemicals can affect pubertal onset. By using the AOP framework, we highlight current gaps in mechanistic understanding that need to be addressed and simultaneously point towards events causative of pubertal disturbance that could be exploited for alternative test methods. We propose 6 pAOPs that could explain the disruption of pubertal timing by interfering with the central hypothalamic trigger of puberty, GnRH neurons, and by so doing highlight specific modes of action that could be targeted for alternative test method development.

Precocious puberty in Korean girls with and without exposure to endocrine-disrupting chemicals in toy slime: a comparative analysis.

BACKGROUND: Toy slime is popular in Korea, and in parallel, pre-pubertal girls visit hospitals for early pubertal signs. Thus far, numerous studies have investigated the association of endocrine-disrupting chemicals (EDCs) with precocious puberty (PP). However, there is a lack of studies on the clinical manifestations and sex hormones. We aimed to investigate early pubertal development in Korean girls with or without a history of toy slime exposure and determine changes in bone age, Tanner stage, and sex hormones. METHODS: In this study, 140 girls underwent stimulation tests at Kyungpook National University Children's Hospital Endocrinology Department, during January 2018 and December 2020. Patients were divided into two groups for gonadotropin-releasing hormone (GnRH) stimulation test and frequency of exposure to toy slime (EDCs). GnRH stimulation test was conducted after an intravenous injection of 100 µg of luteinizing hormone-releasing hormone. Slime exposure was defined as Slime ≥ 3 times/week for ≥ 3 months. RESULTS: History of slime exposure was found in 14 of 58 and 65 of 82 patients in the central PP (CPP) and non-CPP groups, respectively. Slime-exposed patients had advanced bone age, although their Tanner stage was low. Patients with a history of toy slime exposure were 5.5 times more likely to be diagnosed with non-CPP than patients without slime exposure (p < 0.05). CONCLUSIONS: Exposure to toy slime in prepubertal girls may be associated with rapid clinical advancement of pubertal development and bone age, and the patients appear more likely to be diagnosed with non-CPP.

MINI REVIEW: Role of Kisspeptin-GPR54 system in regulation of reproductive functions in human and other mammals.

Kisspeptin is a 54- amino acid peptide that acts as a ligand of a receptor called GPR54 which is basically a transmembrane receptor that spins seven times across the cell membrane and coupled with G-protein. Kisspeptin regulates the development of reproductive functions and the onset of puberty in human and other mammals by acting at the brain, hypothalamus, pituitary and gonad levels of reproductive axis. Kisspeptin is also involved in regulation of trophoblastic invasion during pregnancy, ovulation, and sperm hyperactivation. Inactivating mutations in human kisspeptin gene (KISS1) cause idiopathic hypogonadotropic hypogonadism. Some mutations in human kisspeptin receptor gene (KISS1R) make the receptor inactive which result in idiopathic hypogonadotropic hypogonadism. Some mutations in human KISS1R gene make the receptor prematurely activated and result in the development of central precocious puberty. Central precocious puberty is also caused by some mutations in human KISS1 gene that make the kisspeptin resistant to degradation. This leads to an increased basal kisspeptin level and subsequently the development of central precocious puberty. Higher kisspeptin level has been detected in the serum and plasma of central precocious puberty patients, which suggest that serum or plasma kisspeptin level can be used as a marker for diagnosis of central precocious puberty.

Effects of High-Glucose and High-Fat Condition on Estrogen Receptor- and Sexual Precocity-Related Genes in GT1-7 Cells.

BACKGROUND This study was designed to investigate the effect of high-glucose and high-fat condition on estrogen receptor- and sexual precocity-related genes in GT1-7 cells. MATERIAL AND METHODS In this study, CCK8 was used to detect cell viability, and TUNEL assay was used to detect apoptosis levels of GT1-7 cells after treatment with glucosamine and palmitate. The expression level of GnRH was measured by ELISA and RT-qPCR. RT-qPCR and Western blot were used to detect the expression of ERß, CD36, and GPR54 in GT1-7 cells, and the expression of ERß was detected using immunohistochemistry analysis. Finally, after adding the intervening drug tamoxifen to GT1-7 cells, the expression level of GnRH was measured by ELISA and Western blot analysis was used to detect the expression of GPR54 and GnRH. RESULTS GnRH secretion in the high-fat and high-glucose group increased continuously over time and peaked at 18 h, and GnRH gene expression peaked at 12 h. High-fat and high-glucose conditions also significantly increased the levels of estrogen receptors ß (ERß), fatty acid translocase protein (CD36), and G Protein-Coupled Receptors 54 (GPR54) in GT1-7 cells. After estrogen receptors ß (ER) was inhibited, GnRH secretion and GPR54 expression were decreased at 12 h and 18 h. CONCLUSIONS Our study demonstrates that high-glucose and high-fat conditions promote the secretion of GnRH and ER and the expression of genes related to sexual precocity in GT1-7 cells.

Telomere length is not altered in girls with idiopathic central precocious puberty treated with a GnRH analog - leuprolide acetate.

BACKGROUND: Idiopathic central precocious puberty (iCPP) presents a disproportionate advancement of bone age and maturation, as well as metabolic and endocrinological changes that may be related to effects on telomere biology. OBJECTIVE: To investigate the telomere length in iCPP girls treated with GnRHa. STUDY DESIGN: Observational case-control study with 85 girls, including 45 iCPP treated with GnRHa and 40 controls. It was analyzed age, height, weight and body mass index (BMI), insulin, triglycerides, testosterone, insulin resistance by HOMA, and telomere length by real-time PCR. Statistical analyses were determined by Wilcoxon test and Spearman correlation was carried out. RESULTS: Weight, BMI, insulin level and HOMA index were higher in the iCPP than in the control group (p < .01); without difference between mean ages. The telomere length did not differ between iCPP and control group. However, a negative correlation was observed between the telomere length and age in iCPP (p = .0009) and control group (p = .014), and weight in the iCPP (p = .017). CONCLUSIONS: We did not observe any difference in the telomere length in the iCPP and control group. Even though, some characteristics of the disease, such as increased weight and body fat, negatively influence the telomere biology.

Early menarche is associated with insulin resistance in advanced maternal age before delivery.

Purpose: With the wide implementation of the universal two-child policy in China, the number of pregnant women in advanced maternal age (AMA) will increase gradually. We aimed to assess the association between age at menarche (AAM) and insulin resistance (IR) before delivery in AMA. Methods: A total of 80 pregnant women in AMA were consecutively enrolled before delivery in Zhongda hospital. Pregnant women were stratified into early menarche group and late menarche group according to the age of regular menstruation (about 13 years). At delivery, serum glucose and lipid levels were measured. IR was calculated by the method of homeostasis model assessment 2(HOMA2). Results: The fasting blood insulin (17.68(9.72-36.71) and 10.35(7.76-15.10), respectively; p = .006) and HOMA-IR (2.08(1.18-4.37) and 1.24(0.89-1.78), respectively; p = .005) were higher in early menarche group than in late menarche group. AAM was inversely associated with HOMA-IR in AMA (r= -0.27, p = .014). In the multivariable analysis, AAM in late menarche group was negatively related to the level of HOMA-IR compared to those in early menarche group (ß= -2.275, p≤.0001). Conclusions: Taken together, our findings suggest that AAM was inversely associated with HOMA-IR in AMA. Furthermore, pregnant women in AMA with early menarche might have higher HOMA-IR levels than those with late menarche. Clinical trial registration: Chinese Clinical Trial Registry (No. ChiCTR-RRC-16008714), retrospectively registered.

Revisiting the pineal gland: a review of calcification, masses, precocious puberty, and melatonin functions.

Introduction: The pineal gland, an endocrine organ of the posterior cranial fossa famously involved in sleep and wakefulness, has continually been a topic of scientific advancement and curiosity. Methods: We review present an up-to-date review including the anatomy, embryology, and physiology of the pineal gland and its ability to secrete hormones including melatonin, pathophysiology of pineal gland tumors, cysts, and calcifications, their clinical presentation including their association with parkinsonism and precocious puberty, and various treatment approaches. Results: Exploring the biochemistry of melatonin, various calcification morphologies, and pineal tumors may uncover a wider role and the exhaustive case study consolidation allows clinicians to carefully review the literature and aid their treatment approaches. Conclusion: It is imperative that clinicians and diagnosticians are able to distinguish manifestations of an overlooked gland.

Gonadal Function after Busulfan Compared with Treosulfan in Children and Adolescents Undergoing Allogeneic Hematopoietic Stem Cell Transplant.

Gonadal impairment is an important late effect with a significant impact on quality of life of transplanted patients. The aim of this study was to compare gonadal function after busulfan (Bu) or treosulfan (Treo) conditioning regimens in pre- and postpubertal children. This retrospective, multicenter study included children transplanted in pediatric European Society for Blood and Marrow Transplantation (EBMT) centers between 1992 and 2012 who did not receive gonadotoxic chemoradiotherapy before the transplant. We evaluated 137 patients transplanted in 25 pediatric EBMT centers. Median age at transplant was 11.04 years (range, 5 to 18); 89 patients were boys and 48 girls. Eighty-nine patients were prepubertal at transplant and 48 postpubertal. One hundred eighteen children received Bu and 19 Treo. A higher proportion of girls treated with Treo in the prepubertal stage reached spontaneous puberty compared with those treated with Bu (P = .02). Spontaneous menarche was more frequent after Treo than after Bu (P < .001). Postpubertal boys and girls treated with Treo had significantly lower luteinizing hormone levels (P = .03 and P = .04, respectively) compared with the Bu group. Frequency of gonadal damage associated with Treo was significantly lower than that observed after Bu. These results need to be confirmed in a larger population.

The interference of DEHP in precocious puberty of females mediated by the hypothalamic IGF-1/PI3K/Akt/mTOR signaling pathway.

DEHP is reported to cause precocious puberty of females in both humans and rodents, but the underlying mechanisms were largely unknown. This study was designed to clarify the effects and the mechanisms of DEHP on the pathogenesis of sexual precocity. Prepubertal female rats were treated with DEHP for 4 weeks. Key organs were analyzed in control conditions and after exposure to 0.2, 1, and 5 mg/kg/day DEHP in pubertal female rats. To determine the role of the IGF-1/PI3K/Akt/mTOR signaling pathway in DEHP-induced female precocious puberty, 36 rats were treated with 5 mg/kg/day DEHP to establish a model of female precocious puberty. And we investigated the expression of genes and proteins related to IGF-1 pathway in rat hypothalamus after treatment with inhibitors. In the present study, we observed that DEHP treatment resulted in earlier vaginal opening time, higher number of Nissl bodies in the hypothalamus neurons, lower apoptosis of hypothalamic cells, higher IGF-1 and GnRH levels in the serum and hypothalamus. DEHP could also upregulated the expression of IGF-1/PI3K/Akt/mTOR pathway and GnRH in the hypothalamus of adolescent female rats, and inhibition of IGF-1R and mTOR in hypothalamus could block the activation of Kiss-1, GPR54, and GnRH by DEHP. In summary, our study suggested that DEHP might activate the hypothalamic GnRH neurons prematurely through the IGF-1 signaling pathway and promote GnRH release, leading to the initiation of female sexual development. Our results provide a new molecular mechanism underlying reproductive and developmental toxicity in pubertal female rats induced by DEHP.

Increased symptoms of anxiety and depression in prepubertal girls, but not boys, with premature adrenarche: associations with serum DHEAS and daily salivary cortisol concentrations.

Concerns over anxiety and depressive symptoms in children with premature adrenarche (PA) have been recently raised. However, to date, most relevant studies are on a small number of girls. In this cross-sectional study, 82 pre-pubertal children (66 girls and 16 boys) diagnosed with PA, were compared to 63 control children regarding their psychological characteristics and hypothalamic-pituitary-adrenal (HPA) axis function, as assessed by salivary cortisol measurement. Symptoms of anxiety and depression were assessed by child self-report (Spence Children's Anxiety Scale (SCAS) and Depression self-rating scale for Children (DSRS)) and parent-report (Child Behaviour Checklist (CBCL)) tests validated for the Greek population. Salivary cortisol levels were determined directly after awakening (approximately 7am) and evening (8pm) of the same day. Morning serum DHEAS levels were assessed in PA children. Girls with PA scored significantly higher on anxiety (p = .016) and depression (p =.039) scales than controls. No group differences were noted for parent reports and children's salivary cortisol concentrations. Boys with PA did not demonstrate significant differences in any of the aforementioned parameters. Our findings suggest that girls with PA may be at higher risk for reporting symptoms of anxiety and depression than their non-PA peers. HPA axis dysregulation in this population was not documented.

Paradoxical gain-of-function mutant of the G-protein-coupled receptor PROKR2 promotes early puberty.

The human genome encodes ~750 G-protein-coupled receptors (GPCRs), including prokineticin receptor 2 (PROKR2) involved in the regulation of sexual maturation. Previously reported pathogenic gain-of-function mutations of GPCR genes invariably encoded aberrant receptors with excessive signal transduction activity. Although in vitro assays demonstrated that an artificially created inactive mutant of PROKR2 exerted paradoxical gain-of-function effects when co-transfected with wild-type proteins, such a phenomenon has not been observed in vivo. Here, we report a heterozygous frameshift mutation of PROKR2 identified in a 3.5-year-old girl with central precocious puberty. The mutant mRNA escaped nonsense-mediated decay and generated a GPCR lacking two transmembrane domains and the carboxyl-terminal tail. The mutant protein had no in vitro signal transduction activity; however, cells co-expressing the mutant and wild-type PROKR2 exhibited markedly exaggerated ligand-induced Ca2+ responses. The results indicate that certain inactive PROKR2 mutants can cause early puberty by enhancing the functional property of coexisting wild-type proteins. Considering the structural similarity among GPCRs, this paradoxical gain-of-function mechanism may underlie various human disorders.

Evolution of metabolic alterations 5 Years after early puberty in a cohort of girls predisposed to polycystic ovary syndrome.

BACKGROUND: We and others have observed that young girls predisposed to polycystic ovary syndrome (PCOS) display defective insulin sensitivity, beta-cell function and non-esterified fatty acids (NEFA) suppressibility during early pubertal years, compared to controls. Our objective is to assess whether these differences in glucose and NEFA metabolisms persist after 5 years in late/post-puberty. METHODS: We conducted a prospective cohort study between 2007 and 2015 with 4-6 years of follow-up in an academic institution research center. We compared 8 daughters and sisters of PCOS women (PCOSr) to 8 age-matched girls unrelated to PCOS (±1.5 years). Girls were assessed initially at 8-14 years old and re-assessed after a median follow-up of 5.4 years, at 13-21 years old. Our main measures were a frequently sampled intravenous glucose tolerance test (FSivGTT)-derived insulin sensitivity (IS) and beta-cell function (disposition index, DIFSivGTT); and indices of NEFA suppression during FSivGTT (logn-linear slope of NEFA and T50 of NEFA suppression). RESULTS: At follow-up, both PCOSr and controls had similar results: IS = 3.2 vs 3.4 (p = 0.88), DIFSivGTT = 1926 vs 1380 (p = 0.44), logn-linear slope = -0.032 vs -0.032 (p = 0.88) and T50NEFA = 18.1 vs 20.8 min (p = 0.57). IS, DIFSivGTT and NEFA suppressibility were stable in PCOSr after 5 years, but decreased significantly in controls (all p < 0.05). CONCLUSIONS: Impaired metabolism observed during early puberty in girls predisposed to PCOS remains stable after 5 years whereas control girls deteriorated their metabolic parameters. Therefore, both groups become comparable in late/post-puberty. Early puberty may thus represent a window during which metabolic alterations are transiently apparent in girls at risk of PCOS.

Association between left ventricular mass, androgens, adiposity and insulin resistance in girls with precocious pubarche: a case-control study.

OBJECTIVE: Precocious pubarche (PP) has been linked to higher prevalence of metabolic disturbances and polycystic ovary syndrome (PCOS). The aim of the study was to assess echocardiographic parameters in PP girls and to analyse their relationship with androgens and insulin resistance (IR). DESIGN: Case-control study. PATIENTS: Thirty-five PP girls and 35 healthy age-matched controls. MEASUREMENTS: Clinical, hormonal and metabolic profiles, echocardiography, body composition and oral glucose tolerance test. RESULTS: Chronological age (10·04 ± 2·6 years in PP vs 10·13 ± 2·56 years in controls, P = 0·227), and pubertal stage at the time of the study were similar between the groups. PP girls had higher free androgen index (FAI) [1·39 (0·48-3·64) vs 1·06 (0·39-1·7), P = 0·005] and QUICKI (0·58 ± 0·08 vs 0·63 ± 0·12, P = 0·021). However, HOMA-IR was not significantly different between the groups [2·79 (1·84-4·05) vs 2·15 (1·09-3·23), P = 0·085]. After adjusting for total body fat, left ventricular mass (LVM) was higher in the PP group (97·31 ± 33·37 vs 81·25 ± 19·06 g, P = 0·017) as well as A' wave (5·66 ± 1·34 vs 5·09 ± 0·98 cm/s, P = 0·025), a measurement of diastolic function. FAI and total body fat were independent predictors of higher LVM and together with HOMA-IR contributed 72% of LVM variability in the PP group. CONCLUSION: In this study with PP girls, greater LVM, associated with higher androgen levels, IR and total body fat, occurred early in pubertal development.

DEHP exposure in utero disturbs sex determination and is potentially linked with precocious puberty in female mice.

Human's ubiquitous exposure to di (2-ethylhexyl) phthalate (DEHP) is thought to be associated with female reproductive toxicity. Previous studies found that DEHP inhibited follicle growth and decreased estradiol levels in adult female mice. However, limited information is available on the link between in utero DEHP exposure and ovarian development in female mouse offspring. The present study evaluates the disturbances in regulatory genes involved in female sex determination and the ovarian outcomes in fetal and postnatal female mice treated with in utero DEHP exposure. Pregnant mice were exposed to DEHP by gavage, with the dosage regime beginning at human relevant exposure levels. After in utero DEHP exposure, increased follicular atresia was observed in the female pups at postnatal days (PND) 21. Foxl2 expression was significantly upregulated, and Fst was significantly downregulated by DEHP above 2mg/kg/d at PND 1 and 21. This suggests that lesion of granulosa cell differentiation and disturbance of follicle development in postnatal female mice. The expression of Cyp11a1 and Star were significantly downregulated by in utero DEHP exposure, indicating effects on estradiol biosynthesis. The female sex determination pathway was disturbed in fetus by DEHP at 2mg/kg/d and above during the critical time window of sex determination causing significant upregulation of Foxl2, Wnt4, ß-catenin and Fst. Furthermore, the increased expression of Wnt4 was supported by whole-mount in situ hybridization (WISH). These results suggest a possible association between in utero DEHP exposure and precocious puberty in the postnatal life of mice offspring, where disturbance of the sex determination regulating pathway acted as an important mechanism.

[Kisspeptin and leptin in the regulation of fertility].

Kisspeptin (KISS1) and its receptor (KISS1R) are important regulators of the reproductive function, along with gonadoliberin (GnRH), gonadotropins (luteinizing hormone (LH) and follicle-stimulating hormone (FSH)), and sex steroid hormones. Mutations of their genes alter sexual maturation. The p.P74S, p.H90D, and p.P110T missense mutations of KISS1 are associated with central precocious puberty (CPP); and the p.G35S, p.C53R, and p.F117L mutations, with delayed puberty and isolated hypogonadotropic hypogonadism (IHH). The p.P196H and p.R386P mutations of KISS1R are also associated with CPP. However, a greater number of KISS1R mutations are associated with IHH, as is the case with p.L102P, p.L148S, p.E232Q, p.R297L, p.Y313H, pX399R, and more complex mutations, such as the 155-bp deletion that removes the acceptor splice site of intron 4 and part of exon 5, a deletion of the GCA triplet in position-2 ...-4 of intron 2, and an ACCGGCT insertion in the same site. The heterozygous compound mutations p.C223R/p.R297L and p.R331X/X399R and the 1-bp insertion 1001_1002insC of KISS1R are similarly associated with IHH. Leptin-dependent activation of KISS1 in hypothalamic neurons was observed in mice and sheep, being especially evident after puberty. Leptin exerts a permissive effect in regulating fertility and facilitate the induction of puberty by hypothalamic KISS1 and GnRH and pituitary LH and FSH, which support the reproductive function during further life.

[Effects of Nourishing Yin Removing Fire Chinese Herbs on Gene Expression of Hypothalamic Ghrelin and its Receptor in Female Precocious Rats].

OBJECTIVE: To observe the effect of nourishing yin removing fire Chinese herbs (NYRF-CH) on the gene expression of hypothalamic growth hormone secretion peptide (Ghrelin) and its receptor growth hormone secretion peptide receptor 1alpha (GHSR1-alpha) at the puberty onset of danazol induced female precocious rats. METHODS: Forty female SD rats were randomly divided into 4 groups, i.e., the normal group (N), the model group (M), the normal saline intervention group (NS), and the NYRFCH intervention group (NI), 10 in each group. 300 microg danazol was subcutaneously injected to all rats except those in the N group to prepare precocious rat model. NYRFCH and normal saline was respectively administered to rats in the NI and the NS group from the 15th day old for 7-10 days. No treatment was given to rats in the N group. Time of rats' vulva opening was recorded. Ovary index and uterus index were calculated. Peripheral blood levels of estradiol (E2), follicle stimulating hormone (FSH), and luteinizing hormone (LH), and hypothalamic contents of gonadotropin releasing hormone (GnRH) as well as the gene expression of hypothalamic Ghrelin and GHSR1-alpha were determined. Results Compared with the N group, the vulva opening time was advanced in the model group; peripheral blood levels of E2 and LH, uterus index, hypothalamic contents of GnRH increased; peripheral blood FSH levels and mRNA levels of hypothalamic Ghrelin and GHSR1-alpha decreased (P < 0.05, P < 0.01). Compared with the M group and the NS group, the vulva opening time was not advanced in the NI group; peripheral blood levels of E2 and LH, uterus index and hypothalamic contents of GnRH obviously decreased (P < 0.05, P < 0.01); mRNA levels of hypothalamic Ghrelin and GHSR1-alpha increased (all P < 0.01). But there was no statistical difference in the hypothalamic contents of Ghrelin, or the number and activity of GHSR1-alpha (P > 0.05). CONCLUSION: NYRFCH had regulatory effect on regulating hypothalamic Ghrelin and GHSR1-alpha at gene transcription levels.

Central precocious puberty: from physiopathological mechanisms to treatment.

Puberty is a complex, coordinated biological process with multiple levels of regulations. The timing of puberty varies greatly in children and it is influenced by environmental, endocrine and genetic factors. Precocious puberty (PP) is an important issue, affecting between 1 in 5.000-10.000 children. The physiopathological mechanism is still unknown. From an etiological point of view, PP may be subdivided into gonadotropin-releasing hormone (GnRH) -dependent and independent causes. GnRH-dependent PP, often called central precocious puberty (CPP), is based on hypothalamic-pituitary-gonadal axis activation associated with progressive pubertal development, accelerated growth rate and advancement of skeletal age. Conversely, peripheral precocious puberty (PPP) is related to sex steroid exposure, independently of hypothalamic-–pituitary-–gonadal (HPG) axis activation. Kisspeptins play a central role in the modulation of GnRH secretion with peripheral factors that influence the timing of puberty, such as adipokines and endocrine disrupting chemicals. Moreover, PP could be related to genetic disorders, involving pivotal genes of the HPG axis. The standard test used to verify HPG activity is the gonadotropin response to administered GnRH analogs. We describe the physiopathological mechanisms of PP and its clinical implications, analysing diagnostic flow-chart and new potential biomarkers that could reveal PP. An update of the current literature was also carried out regarding the recent novelty for treatment.