Fernando Cassorla

The Advantage of Measuring Stimulated as Compared with Spontaneous Growth Hormone Levels in the Diagnosis of Growth Hormone Deficiency

To clarify the relative usefulness of measuring stimulated as compared with spontaneous growth hormone levels in the diagnosis of growth hormone deficiency, we studied 54 short prepubertal children--23 with growth hormone deficiency identified by stimulation tests and 31 with idiopathic short stature who had normal responses to growth hormone stimulation. Growth hormone levels were measured in plasma samples obtained every 20 minutes for either 12 or 24 hours. The results were compared with those in 46 normal prepubertal children. Children with growth hormone deficiency had significantly lower mean 24-hour growth hormone levels (1.0 microgram per liter; range, 0.5 to 1.8) than normal children (2.8 micrograms per liter; range, 0.8 to 5.8; P less than 0.001). However, the diagnostic usefulness of the spontaneous growth hormone test was inferior to that of the stimulation tests, since it identified only 57 percent of the children with growth hormone deficiency identified by the stimulation tests. In the remaining children with growth hormone deficiency, spontaneous growth hormone levels were within the normal range. Children with idiopathic short stature had a normal mean 24-hour level of growth hormone (3.0 micrograms per liter; range, 1.1 to 6.7). No child in this group had low levels of spontaneous growth hormone secretion. We conclude that the measurement of the spontaneous secretion of growth hormone in prepubertal short children had lower sensitivity and offered no diagnostic advantage over stimulation tests. Our data do not support the routine measurement of spontaneous growth hormone secretion in the diagnosis of growth hormone deficiency.

Metabolic and Reproductive Features before and during Puberty in Daughters of Women with Polycystic Ovary Syndrome

CONTEXT A significant proportion of the first-degree female relatives of women with polycystic ovary syndrome (PCOS) may be at risk for developing PCOS. However, it is not known at which stage of pubertal development the hormonal and metabolic abnormalities ensue in PCOS. OBJECTIVE The aim of the study was to assess the reproductive and metabolic profiles of daughters of women with PCOS (PCOSd) during the peripubertal period, a stage during which the gonadal axis is activated and PCOS may become clinically manifest. DESIGN Ninety-nine PCOSd [30 prepubertal and 69 pubertal (Tanner II-V)] and 84 daughters of control women (Cd) (20 prepubertal and 64 pubertal) were studied. An oral glucose tolerance test, a GnRH agonist test (leuprolide acetate, 10 microg/kg sc), and a transabdominal ultrasound were performed. Gonadotropins, sex steroids, SHBG, glucose, insulin, and lipids were determined. RESULTS Both groups had similar chronological ages and body mass index sd scores according to Tanner stage distribution. Ovarian volume and 2-h insulin were significantly higher in PCOSd compared to Cd at all Tanner stages. In Tanner stages IV and V, basal testosterone and poststimulated LH, testosterone, and 17-hydroxyprogesterone concentrations were significantly higher in PCOSd compared to Cd. CONCLUSIONS Hyperinsulinemia and an increased ovarian volume are present in PCOSd before the onset of puberty and persist during pubertal development. The biochemical abnormalities of PCOS appear during late puberty. Considering the early onset and the nature of the alterations, PCOSd constitute a high-risk group for metabolic and reproductive derangements.

Metabolic Profile in Sons of Women with Polycystic Ovary Syndrome

CONTEXT Polycystic ovary syndrome (PCOS) is a common endocrine-metabolic disorder with strong familial aggregation. It has been demonstrated that parents and brothers of PCOS women exhibit insulin resistance and related metabolic defects. However, metabolic phenotypes in sons of PCOS women have not been described. OBJECTIVE Our objective was to assess the metabolic profiles in sons of women with PCOS during different stages of life: early infancy, childhood, and adulthood. DESIGN Eighty sons of women with PCOS (PCOS(S)) and 56 sons of control women without hyperandrogenism (C(S)), matched for age, were studied. In early infancy, glucose and insulin were determined in the basal sample. In children and adults, a 2-h oral glucose tolerance test was performed with measurements of glucose and insulin. Adiponectin, leptin, C-reactive protein, SHBG, and serum lipids were determined in the basal sample during the three periods. RESULTS During early infancy, PCOS(S) showed higher weight (P = 0.038) and weight sd score (P = 0.031) than C(S). During childhood, weight (P = 0.003), body mass index (BMI) (P < 0.001), BMI sd score (P < 0.001), waist circumference (P = 0.001), total cholesterol (P = 0.007), and low-density lipoprotein cholesterol (P = 0.022) were higher in PCOS(S) compared with C(S), but after adjusting for BMI, these differences were nonsignificant. During adulthood, PCOS(S) exhibited higher weight (P = 0.022), BMI (P = 0.046), and waist circumference (P = 0.028) than C(S). Fasting insulin (P = 0.030), homeostasis model assessment for insulin resistance (P = 0.034), total cholesterol (P = 0.043), low-density lipoprotein cholesterol (P = 0.034), and 2-h insulin (P = 0.006) were also significantly higher and insulin sensitivity index composite significantly lower in PCOS(S) than in C(S) (P = 0.003). After adjusting for BMI, only 2-h insulin and insulin sensitivity index composite remained significantly different. CONCLUSIONS This study indicates that sons of PCOS women exhibit higher body weight from early infancy. In addition, insulin resistance became evident as the subjects got older, which may place them at risk for the development of type 2 diabetes and cardiovascular disease.

Puberty and Ovarian Function in Girls with Type 1 Diabetes Mellitus

Insulin is well known for its effects on carbohydrate metabolism, but this hormone also plays an important role in regulating ovarian function. Granulosa, theca and stromal ovarian cells may be affected by insulin deficiency or excess, which may be present in women with type 1 diabetes mellitus (T1D). Recent publications have shown that in spite of intensive insulin therapy, some delay in the age of thelarche, pubarche and menarche is still observed in girls with T1D. In addition, ovarian hyperandrogenism may be observed during late adolescence and an increased prevalence of hirsutism and polycystic ovarian syndrome (PCOS) has been described in adult women with T1D. These endocrine abnormalities may be related to nonphysiologic insulin replacement therapy and to hyperglycemia. This paper reviews the pubertal development and the clinical reproductive abnormalities observed in girls with type 1 diabetes mellitus, and shows that several significant clinical problems, such as pubertal delay, menstrual disturbances and hyperandrogenism which may ultimately lead to the development of PCOS in adulthood, may be observed in some of these patients.

Ponderal gain, waist‐to‐hip ratio, and pubertal development in girls with type‐1 diabetes mellitus

Abstract:  Objectives:  We assessed pubertal development, height, weight, and waist‐to‐hip ratio (WHR), an index of central adiposity during puberty, in girls with type‐1 diabetes mellitus (T1DM), compared to a contemporary control group.

Sex-specific response of bone cells to gonadal steroids : modulation in perinatally androgenized females and in testicular feminized male rats

We have found previously that rat diaphyseal bone in vivo, as well as rat embryo calvaria cells in culture, show a sex-specific response to gonadal steroids in stimulation of creatine kinase (CK)-specific activity, and the rate of [3H]thymidine incorporation into DNA; male-derived cells responded only to testosterone or to dihydrotestosterone (DHT), whereas female-derived cells were stimulated exclusively by estradiol (E2). In this study, we tested whether developmental hormone manipulation could alter this sex specificity. We showed that diaphyseal bone of prenatally or neonatally androgenized female rats responds to a single injection of either E2 (5 micrograms/rat) or DHT (50 micrograms/rat) at 3-4 weeks postandrogenization. This response of androgenized female diaphyseal bone to androgen gradually declines; 3 months posttreatment, diaphyseal bone no longer responds to DHT and reverts to its original sex specificity. Rat embryo calvaria cell cultures prepared from female fetuses androgenized in utero showed the same lack of hormonal specificity, that is, the cells responded to both E2 (30 nM) or DHT (300 nM). Cells derived from the male siblings of the prenatally androgenized rats were not affected and responded only to DHT. In contrast to experiments in utero, in vitro administration of testosterone (1 microM) or E2 (1 microM) to calvaria cells from female embryos failed to cause the cells to respond to DHT. Androgen receptor-deficient (Tfm) male rats, which have approximately 10% of the normal response to androgens, also showed a response to both testosterone and E2 in comparison to their normal male siblings, whose bones responded only to androgens.(ABSTRACT TRUNCATED AT 250 WORDS)

Pubertal Growth: Physiology and Pathophysiology

Publisher Summary This chapter provides an overview of pubertal growth. The current hypothesis is that pubertal growth in girls is driven by low levels of estrogen, on the order of about 4 μg/day, whereas pubertal growth in boys is driven both by low levels of estrogen and by high, that is, late pubertal levels of androgen. Earlier investigators have established that growth hormone and thyroxin play a permissive role in pubertal growth. The contribution of increased growth hormone and somatomedin C secretion at puberty to the pubertal growth spurt, however, is uncertain. Normal pubertal growth rates can be achieved without increased circulating growth hormone or somatomedin C in growth hormone-replaced, sex steroid-treated hypo pituitary children. Clinical evidence suggests that the adrenal androgens contribute little if anything to pubertal growth. In girls with Turner syndrome, who normally lack a pubertal growth spurt, low dose estrogen increases growth rate and improves predicted height. In the children with central precocious puberty, long-term LHRH analog treatment decreases growth rate and bone maturation and improves predicted height. In boys with familial male precocious puberty, control of pubertal growth appears to require removal of the effects of both androgens and estrogens. The potential to enhance height by delay of normal puberty is likely to be modest.

Effects of Birth Weight on Anti-Müllerian Hormone Serum Concentrations in Infant Girls

CONTEXT We previously demonstrated that low birth weight (BW) infant girls show increased serum anti-Müllerian hormone (AMH) concentrations and poststimulated estradiol levels compared to normal-BW infants, suggesting an altered follicular development. However, the impact of high BW on reproductive function is less known. OBJECTIVE To evaluate the effect of BW on AMH, we determined the concentrations of this hormone in low-BW, normal-BW, and high-BW female infants during the first 3 months of life. DESIGN Twenty-seven low-BW, 29 normal-BW, and 28 high-BW infant girls were studied. We measured serum gonadotropins, steroid hormones, AMH, glucose, insulin, free fatty acids, IGF-I, and adiponectin in a fasting blood sample. In addition, in a subgroup of normal-BW (n = 23) and high-BW infants (n = 10), a GnRH analog leuprolide acetate test was performed. RESULTS Serum concentrations of AMH were higher in low-BW and high-BW infants compared to normal-BW infants (P = 0.028 and 0.022, respectively). In addition, in high-BW infants, adiponectin concentrations were lower (P = 0.018), and poststimulated FSH and estradiol levels were higher compared to normal-BW infants (P = 0.024 and 0.047, respectively). CONCLUSIONS Serum AMH and poststimulated estradiol concentrations are increased in low-BW and high-BW female infants, suggesting that these girls may show evidence of an altered follicular development. However, the increased poststimulated FSH levels and low adiponectin concentrations observed in high-BW infants suggest that ovarian function is perturbed through a different mechanism from that in low-BW infants.

Edad de la menarquia y su relación con el nivel socioeconómico e índice de masa corporal

BACKGROUND A decline in the age of menarche was observed from early 1900s to the 1970s. However, it is not known if a further decline occurred thereafter. AIM To evaluate the age of menarche in girls from Santiago, Chile and its relationship with body mass index (BMI) and socioeconomic status. MATERIAL AND METHODS We studied 1302 healthy girls aged 7 to 19 years. Age of menarche was evaluated through a questionnaire to the patient and her parents. Kaplan-Meier curves were used to determine age of menarche and Cox regression analysis was employed to evaluate the effect of the type of school and BMI on the age of menarche. RESULTS The mean age at menarche was 12.7+/-0.04 years. Girls from public and private schools had their period at 12.5+/-0.1 and 13.05+/-0.05 years respectively. A negative correlation between z scores for BMI and age of menarche was observed (r-0.3: p =0.001). Girls whose menarche occurred before 11.5 years had higher z scores for BMI and a larger proportion were overweight, compared to girls who had menarche later. Cox regression analysis showed that after adjustment for BMI, age of menarche was similar in both types of schools. CONCLUSIONS Age of menarche is occurring three months earlier in girls from public schools, which is associated with higher z scores for BMI. Type of school, a marker of socio-economic status in Chile, affects timing of menarche due to differences in body mass index.

New evidence for a direct effect of prolactin on rat adrenal steroidogenesis.

The direct effect of prolactin on rat adrenal steroidogenic enzyme activity was evaluated by measuring plasma and adrenal cytosol steroid levels and adrenal microsomal 3B-hydroxysteroid dehydrogenase/isomerase (3B-HSD), 21 hydroxylase (21-OHase) and mitochondrial 11-hydroxylase (11-OHase) after in vivo administration of purified rat prolactin (rPRL) to adult, female Sprague-Dawley rats. Animals were ovariectomized, hypophysectomized and replaced with ACTH. Two days after surgery rPRL was administered i.p. at doses of 1.0, 10.0 and 100.0 micrograms (micrograms) every 4 hours for 5 days to experimental animals. Control rats received vehicle injections. All rats were sacrificed by decapitation and blood and adrenal glands collected. The adrenals were pooled into each rPRL dose group and mitochondria, microsomes and cytosol prepared from each pool. The activities of 3B-HSD, 21-OHase and 11-OHase were measured using as substrates 14C-dehydroepiandrosterone, 14C-progesterone and 14C-deoxycorticosterone, respectively. Plasma prolactin levels rose from 9.9 +/- 2.5 ng/ml in the control animals to 166.0 +/- 37.7 ng/ml (p less than 0.001) in the 100 micrograms rPRL dose group. Plasma corticosterone levels were not statistically different in the experimental groups when compared to controls. However, adrenal weight was increased in the high dose rPRL group (34.9 +/- 0.9 mg vs 41.9 +/- 1.2 mg, p less than 0.025). Hyperprolactinemia did not influence microsomal 3B-HSD or mitochondrial 11-OHase activities but was associated with a dose dependent decrease in microsomal 21-OHase activity when compared to controls (p less than 0.001). Adrenal cytosol progesterone levels increased with increasing rPRL dose consistent with a 21-OHase block during hyperprolactinemia. These data suggest that prolactin has a direct effect on rat adrenal 21-OHase in vivo.