Adrenal Steroids in Female Hypothyroid Neonates: Unraveling an Association Between Thyroid Hormones and Adrenal Remodeling.

CONTEXT: The adrenal gland undergoes substantial remodeling during the neonatal period, an essential developmental process that remains incompletely understood. With respect to control over the remodeling process and, specifically, the role of thyroid hormones (THs), no human studies have been published. The effects of both hypo- and hyperthyroidism have only been evaluated in adults, focusing on the mature adrenal. Recent studies have identified expression of the TH receptor ß1 in the mouse adrenal X-zone and have demonstrated that TH administration could alter the postnatal adrenal remodeling process. OBJECTIVE: To address whether THs influence adrenal steroid profiles and adrenal remodeling during the neonatal period. METHODS: We compared the adrenal steroid profile of a naturally occurring prototype, female neonates with severe congenital hypothyroidism (CH) (n = 22, upon diagnosis of CH), with that of euthyroid neonates (n = 20). RESULTS: Significantly higher levels of adrenal steroids (17-OH-progesterone, dehydroepiandrosterone sulfate, Δ4-androstenedione, and testosterone) were measured in neonates with severe CH compared with euthyroid neonates and returned to within normal range after euthyroid state had been established on l-thyroxine replacement therapy, whereas cortisol levels did not differ. TSH values in the CH group were positively correlated with circulating adrenal steroids, whereas free T4 levels were negatively correlated with circulating adrenal steroids. CONCLUSIONS: The hormonal profile of female neonates with severe CH suggests a more active adrenal fetal zone compared with control subjects. These data indirectly associate THs with the adrenal remodeling and maturation process in humans. Based on our results, we suggest that severe hypothyroidism decelerates the involution of the adrenal fetal zone that normally occurs postnatally.

The combined effect of MC4R and FTO risk alleles on childhood obesity in Greece.

OBJECTIVE: Single nucleotide polymorphism (SNP) risk alleles of obesogenic genes, such as the fat mass and obesity-associated protein (FTO) and the melanocortin-4 receptor (MC4R) gene, have been described in both paediatrics and adult populations. The aim of this study was to investigate the combined effect of FTO and MC4R risk alleles on the obese phenotype and metabolic profile of young children and adolescents of Greek origin. DESIGN: One hundred and fifty-three overweight and obese Greek children (mean age 11.08±2.23 years) and 151 age-matched normal-weight controls were enrolled. Along with anthropometric and standard biochemical profile genetic analysis for the high-risk rs9939609 A allele of the FTO gene and the high-risk C allele of the rs17782313 polymorphism downstream of the MC4R gene were investigated in all participants. RESULTS: The combined presence of three or more high-risk alleles of both the FTO and MC4R genes confers a 4-fold higher risk for obesity in children and adolescents of Greek origin, although these risk alleles have no impact on the metabolic alterations observed in these obese children and adolescents. CONCLUSIONS: There is a synergistic effect of the high-risk alleles of the FTO and MC4R genes on the obese phenotype, while no impact on the metabolic abnormalities was observed in Greek obese children and adolescents.

Long-term clinical data and molecular defects in the STAR gene in five Greek patients.

CONTEXT: Steroidogenic acute regulatory (STAR) gene mutations lead to adrenal and gonadal failure. Interesting, though as yet unexplained, features are the formation of ovarian cysts and the potential presence of CNS findings. OBJECTIVE: To report biochemical, genetic, and long-term clinical data in five Greek patients from four different families with STAR gene defects (three 46,XX and two 46,XY). METHODS AND RESULTS: All patients presented in early infancy with adrenal insufficiency. The STAR gene mutation c.834del11bp, detected in three of our patients, completely alters the carboxyl end of the STAR protein and has not thus far been described in other population groups. These three patients belong to three separate families, possibly genetically related, as they live in different villages located in a small region of a Greek island. However, their interrelationship has not been proven. A second mutation, p.W250X, detected in our fourth family, was previously described only in two Serbian patients. Ovarian cysts were detected ultrasonographically in our 46,XX patients and seemed to respond to a low dose of a contraceptive. The histology of an excised ovarian cyst was diagnosed as a corpus luteum (CL) cyst. In two out of the four patients who had undergone brain magnetic resonance imaging, asymptomatic Chiari-1 malformation was observed. CONCLUSIONS: The occurrence of STAR gene mutation c.834del11bp in three families living in a restricted geographic region could indicate either a founder effect or simply reflect a spread of this defect in a highly related population. The ovarian histological findings suggest that ovarian cysts detected ultrasonographically in 46,XX individuals with STAR gene defects may be CL cysts. The Chiari-1 malformation in two of our patients may be part of the STAR gene mutation phenotype. Nevertheless, more data are needed to confirm or disprove the existence of specific CNS pathology in patients with STAR gene mutations.