Progression Of Pubertal Development Research Articles

Deferiprone and desferrioxamine combined chelation could improve puberty of adolescent males with β-thalassemia major with preserved pituitary and testicular function

Background Transfusion-chelation increased the longevity of patients with β-thalassemia major; thus, puberty and fertility disorders became more apparent. Aim We aimed to evaluate the pituitary–testicular axis and the progress of puberty after using deferiprone (DFP) and desferrioxamine (DFO) combined chelation in patients with preserved pituitary and testicular functions and to assess the quality of semen analysis in relation to chelation type. Patients and methods We carried out a 3-year prospective study of pubertal status including 42 polytransfused males (≥14 years) with thalassemia. Patients with delayed puberty were tested for pituitary–testicular axis function. Those with good pituitary and testicular response were shifted to combination chelation. Compliance on chelation and biannual serum ferritin were assessed. Spermiograms were performed at least twice for pubertal males. Results The median age of the participants was 20 years at enrollment, and 13 patients (30.9%) had normal puberty; they were on DFP 7/28, DFO 2/10, or combination 4/4 for at least 2 years before enrollment. Of the 29 nonpubertal males, 13 (44.8%) had good pituitary–testicular responses; within 3 years, 8/13 progressed to puberty using the combination chelation. Of the 21 pubertal males, 19 consented to spermiograms, with a low sperm count in 4/19 (21.1%) and poor motility in 6/19 (31.6%) patients, respectively. Conclusion Initial evaluation of adolescents and young adult thalassemic males showed that almost two-third were nonpubertal. Combination chelation (DFP and DFO) for those with good pituitary–testicular function led to progression of pubertal development after 3 years in half of them; meanwhile, semen quality was still impaired in one-third of them.

Ovarian Function and Reproductive Hormone Levels in Girls with Prader-Willi Syndrome: A Longitudinal Study

The etiology of hypogonadism in girls with Prader-Willi syndrome (PWS) remains uncertain. The aim of the study was to evaluate gonadal function longitudinally in girls and female adolescents with PWS. We performed a longitudinal assessment of anti-müllerian hormone (AMH), gonadotropins, estradiol (E(2)), inhibin B and A, and pubertal development in girls and female adolescents with PWS. Sixty-one girls participating in the Dutch PWS Cohort study participated in the study. Serum AMH, gonadotropins, E(2), and inhibin B and A levels were compared with reference values. AMH levels in girls and female adolescents with PWS were comparable to reference levels between 6 months and 22 yr of age. From 10 yr of age, FSH and LH levels increased to above the 5th percentile compared to reference levels. E(2) and inhibin B levels were in the low normal range in the majority, and inhibin A levels were low but detectable in almost half the female adolescents with PWS. The median age at puberty onset was comparable, but the median ages at attaining Tanner M3 (P = 0.05) and M4 (P < 0.0001) were significantly higher in girls with PWS than in healthy references. Our study shows that the primordial follicle pool and number of small antral follicles are conserved in girls and female adolescents with PWS. We found no classical hypogonadotropic hypogonadism. However, maturation of follicles and progression of pubertal development are impaired, which might be due to dysregulation of LH secretion. Because these impairments are not absolute, ovulation and thus conception cannot be ruled out in individual female adolescents with PWS.

Early onset of puberty in young girls: an Italian cross-sectional study.

International literature and clinical practice have referred to Marshall and Tanner data to define the physiological age at onset of puberty. A study in the United States (1997) showed an anticipation in pubertal onset, whereas several European studies did not confirm this trend. To describe the onset of secondary sexual characteristics in a large Italian population of girls and to compare it to reference literature data. A cross-sectional study on 7311 2-14-yr-old girls who spontaneously requested a clinical evaluation for routine health check-up or acute illness by family pediatrician's offices in a northern Italian region (Lombardy), between September 2005 and November 2006. Trained family pediatricians performed a complete physical examination; pubertal status was evaluated following Tanner's criteria; breast development was assessed by palpation. Mean age of thelarche (B2), pubarche (PH2), menarche were 9.75, 10.09, and 12.49 yr, respectively. The prevalence of B2 and PH2 at ages 7-7.99 was 5.9% and 5.6%, respectively, at ages 8-8.99 was 15.5% and 13.8%, respectively. Mean time lapse from B2 to B3 and B2 to menarche was 1.46 and 2.74 yr, respectively. Mean age at menarche of our population and their respective mothers was almost identical. Our population presented earlier clinical signs of pubertal development than those defined by Marshall and Tanner. Mean age of menarche was not different in comparison to the previous generation. A different progression of pubertal development was found, in which the shift to B3 may have more clinical relevance.

Longitudinal Study of the Simultaneous Secretion of Melatonin and Leptin during Normal Puberty

Background/Aims: Pubertal changes are a consequence of the activation of the hypothalamic-pituitary-gonadal axis due to an increase in the frequency and magnitude of pulses of gonadotropin-releasing hormone (GnRH), which may depend on the intrinsic properties of the neurons of the hypothalamic arcuatus nucleus, or on the influence of neurotransmitters and/or neuromodulators. We evaluated the serum concentrations of melatonin and leptin in healthy prepubertal and adolescent subjects of both sexes, to define their participation at the initial stages and during the progression of pubertal development. Methods: 80 pediatric subjects (47 females and 33 males), aged 6–18 years, were divided into 2 groups, prepubertal (n = 25) and adolescent (n = 55), according to the absence or presence, respectively, of physical signs of pubertal development. The subjects were assessed on two occasions: at the time of their inclusion in the study, and 12–18 months later when the subject had advanced one pubertal stage according to the Tanner classification. Blood was obtained in fasting for clinical purposes and for the hormonal study. Melatonin and leptin were measured by radioimmunoanalysis. Results: As described previously, melatonin decreases at the onset of puberty and during pubertal development. Both the absolute melatonin value and the decrease between evaluations tended to be greater in females; the variations were correlated with neither an increase in body weight nor with the degree of pubertal development. The concentration of leptin increased in both sexes with the progression of puberty, this value being 40% greater in women, and correlated with the indicators of an increase in body volume and fat accumulation. Although its concentration remained stable between evaluations for both sexes, among the males the association between leptin and pubertal development took place at the start of the process, while for the females we observed a significant overall association between pubertal stage and leptin concentration, this association being stronger at more advanced Tanner stages. Neither at the onset of puberty nor during its course did we observe any significant relation between melatonin concentration and any of the Tanner stages, whether for males or for females. Neither was there any correlation between the absolute values or rates of modification of melatonin and leptin. Conclusion: According to the evolutionary dynamics of their respective concentrations, both initially and during pubertal progress, melatonin and leptin do not interact in the initiation or progression of human pubertal development, and do not seem to play a key role in this process.

Genetic features of the X chromosome affect pubertal development and testicular degeneration in adolescent boys with Klinefelter syndrome

To investigate how genetic features of the X chromosome influence growth, pubertal development and testicular degeneration in adolescent boys with Klinefelter syndrome (KS). Previous studies have suggested that genetic features of the X chromosome may contribute to the wide phenotypic variation in KS. A prospective clinical study. Fourteen nonmosaic 47,XXY boys, aged 10-13.9 years. The relationship of genetic features of the X chromosome, including parental origin of X chromosomes, the CAG repeat length of the androgen receptor (AR) gene, and X inactivation with progression of pubertal development, growth and testicular function in KS boys. Paternal (47,XmXpY, n = 3) as compared to maternal (47,XmXmY, n = 11) origin of the supernumerary X chromosome was associated with a later onset of puberty. In 47,XmXpY patients, serum LH concentrations increased above 1.0 IU/l at 12.5 +/- 0.6 years (mean +/- SD), Tanner stage P2 occurred at 12.5 +/- 0.7 years, and pubertal acceleration of growth was noted at 13.9 +/- 1.4 years and peak velocity at 14.5 +/- 0.8 years. All of these occurred 1.3-1.9 years later than in 47,XmXmY patients (P = 0.01-0.09). In 47,XmXmY subjects, CAG repeat length (range 17-26) correlated with age at which serum LH level first exceeded 1.0 IU/l (rs = 0.63, P = 0.06, n = 10) and testosterone 1.0 nmol/l (28.8 ng/dl) (rs = 0.78, P = 0.02, n = 10). Paternal origin of the supernumerary X chromosome is associated with later onset of puberty and longer CAG repeats of the AR with later pubertal reactivation of the pituitary-testicular axis in KS boys. Identifying genetic factors that affect the phenotype may lead to a better understanding of the pathogenesis of KS.

Growth, puberty and hypothalamic-pituitary function in children with suprasellar arachnoid cyst.

A suprasellar arachnoid cyst may cause disorders of growth, puberty and hypothalamic-pituitary function, due to the proximity of the cyst to the hypothalamic-pituitary area. A total of 30 patients (17 boys) with cyst diagnosed at 4.3 +/- 1 years were routinely evaluated at 5.4 +/- 1 years; 24 of them had one or multiple cyst derivations. Some 23 cases had an abnormal height, weight or puberty: short (< -2SD, 5 cases) or tall ( > 2SD, 10 cases) stature, overweight (body mass index, BMI, > 2SD, 6 cases), central precocious puberty (10 cases) and/or no progression of pubertal development (3 cases). The growth hormone (GH) peaks after pharmacological stimulation test were low (< 10 MICROg/L) in 16 patients, confirmed by a second evaluation in 8/11 of them. The plasma free thyroxine was low in five patients, prolactin was high in two and the cortisol and concomitant plasma and urinary osmolalities were normal. BMI was correlated negatively with the GH peaks (r = -0.37, P < 0.01) and positively with the plasma leptin concentrations (r = 0.55, P < 0.01). The plasma fasting insulin concentrations were also correlated negatively with the GH peaks (r = -0.55, P < 0.02) and positively with the plasma insulin-like growth factor I concentrations (r = 0.64, P < 0.002). The adult height (12 cases) was at 4SD in 1 and < -2SD in 4 patients, two of whom had precocious puberty untreated with gonadotropin releasing hormone (GnRH) analogue, and two had untreated GH deficiency. The adult height of those treated was normal. One girl had primary amenorrhoea and two boys had low plasma testosterone, despite a normal gonadotropin response to a GnRH test. Suprasellar arachnoid cysts may cause deficiencies of growth hormone and thyrotropin, stimulation of the hypothalamic-pituitary-gonadal axis, tall stature and/or overweight. These last two disorders may be due to hyperinsulinism, itself due to suprasellar arachnoid cyst.

Precocious puberty in children with myelomeningocele: treatment with gonadotropin-releasing hormone analogues.

In patients with myelomeningocele (MMC), growth is influenced by a large number of growth-retarding factors due to the neurological defect. Moreover, endocrine disorders have been found to contribute to short stature in MMC patients. Central precocious puberty (CPP) is a common problem. Due to growth disturbances and difficulties in obtaining standardized measurements, MMC patients have been excluded from gonadotropin-releasing hormone (GnRH) analogue studies in the past. We report on eight patients (six female, two male) with MMC, hydrocephalus, and CPP who were treated with GnRH analogues: triptorelin intramuscularly (N=5) or leuprorelin subcutaneously (N=3). Auxological data and hormone levels were assessed before treatment and every 6 months during treatment. The median chronological ages (CA) at the start of treatment were 8.6 years (females) and 8.4 years (males). Bone age (BA) was accelerated in all cases prior to treatment and two girls were already menstruating. Elevated gonadotropin serum levels and sex steroid levels decreased during treatment, although no complete suppression to prepubertal levels was reached. Progression of pubertal development and menses stopped in all patients. The tempo of BA acceleration (deltaBA:deltaCA) decreased, but no significant improvement in height standard deviation score BA and predicted adult height resulted. No side effects during treatment were observed. CPP in MMC patients has to be considered as early as possible to enable an early diagnosis and corresponding treatment. Further prospective studies on the effects of GnRH analogues in MMC patients are necessary.

Atherosclerosis precursors in Finnish children and adolescents. VII. Serum immunoreactive insulin.

In the Finnish Multicentre Study of the risk factors of coronary heart disease serum immunoreactive insulin (IRI) was measured in 3,486 children and adolescents aged 3-18 years. Serum IRI increased with age till the age of 15 years in both sexes. The increase in serum IRI levelled off with the progression of pubertal development. Serum IRI levels were higher in girls than in boys from the age of 6 years onwards. Comparison of serum IRI gave identical results from eastern and western parts of the country. Serum IRI correlated positively with skinfold thickness, weight, relative weight and body mass index in all age groups except the 3-year-old children.

Pubertal development: Normal, precocious and delayed

The present concepts on the neuroendocrine mechanisms which trigger pubertal development and modulate the progression towards sexual maturity have been reviewed. Essentially, puberty is presented as a continuum, the programming of which is initiated prenatally and which ends in adult life when all hormonal secretions become autoregulated. This continuum is dependent on a delicate equilibrium between CNS neurohormones (GnRH), neurotransmitters (biogenic amines), pituitary gonadotrophin (FSH, LH) secretion and the end-organ response (testis or ovary) through the activation of specific membrane receptors. The gonadal sex steroids (T, OE2) will activate specific cytoplasmic and nuclear receptors of target tissues and exert their biological action. Initially, the activity of the HPGA is manifested by nocturnal LH peaks, followed by increased gonadal secretion of T or OE2. Extremely sensitive to negative feedback by circulating androgen and/or oestrogen in prepuberty, an hypothalamic regulatory system called the gonadostat increases its threshold of sensitivity and eventually becomes autoregulated at a higher feedback level. Progressively, the hypothalamus becomes sensitive to positive feedback action of gonadal hormones, this phenomenon being important for the onset of ovulation. It is likely also that adrenal androgens play a permissive and supportive role in the onset and progression of pubertal development. Finally, full maturity is reached, with final adult height through fusion of the epiphysis, and fertility is achieved. The clinical manifestations of each developmental stage of puberty are described and abnormalities of sexual development reviewed. While over 90 per cent of cases of precocious pubertal development are idiopathic in girls, a space-occupying lesion in the hypothalamic-pituitary region is frequent in boys. Dissociated pubertal signs (premature adrenarche, pubarche, thelarche, menarche) are discussed, together with diagnosis and treatment of precocious puberty, whether it is idiopathic or occurring independently of the activation of the HPGA. In addition to delay of puberty on a constitutional basis, or related to chronic endocrine or non-endocrine diseases, the main clinical entities with gonadal insufficiency, primary (hypergonadotrophic) or secondary (hypogonadotrophic), are reviewed in boys and girls and their investigation and treatment discussed.