Hyperandrogenism in female athletes with functional hypothalamic amenorrhea: a distinct phenotype

Asma Javed,1 Rahul Kashyap,2 Aida N Lteif1 1Pediatric and Adolescent Medicine, Division of Pediatric Endocrinology Mayo Clinic, Rochester, MN, USA; 2Department of Anesthesia and Critical Care Medicine, Mayo Clinic, Rochester, MN, USA Objective: To compare the reproductive, metabolic, and skeletal profiles of young athletic women with functional hypothalamic amenorrhea (FHA) as well as clinical or biochemical hyperandrogenism (FHA-EX+HA) with body mass index matched women with FHA due to exercise (FHA-EX) or anorexia nervosa (FHA-AN) alone.Design: Retrospective cohort study.Setting: Tertiary care teaching hospital.Population: Adolescents and young women, 15–30 years of age, diagnosed with FHA along with concurrent signs of hyperandrogenism (n=22) and body mass index matched control groups consisting of 22 women in each group of FHA-EX and FHA-AN. Main outcomes: 1) Reproductive hormone profile: luteinizing hormone (LH), follicle stimulating hormone (FSH), total testosterone, pelvic ultrasound features. 2) Metabolic function and skeletal health markers: fasting glucose, cholesterol, number of stress fractures and bone mineral density as assessed by spine dual-energy X-ray absorptiometry z scores. Results: FHA-EX+HA group was older at diagnosis compared to the other groups with a median (interquartile range [IQR]) age of 22 (18.75–25.25) years versus (vs) 17.5 (15.75–19) for FHA-EX; (P<0.01) and 18 (16–22.25) years for FHA-AN (P=0.01). There were no differences among the groups based on number of hours of exercise per week, type of physical activity or duration of amenorrhea. Median (IQR) LH/FSH ratio was higher in FHA-EX+HA than both other groups, 1.44 (1.03–1.77) vs 0.50 (0.20–0.94) for FHA-EX and 0.67 (0.51–0.87) for FHA-AN (P<0.01 for both). Total testosterone concentrations were not different among the groups. Median (IQR) fasting serum glucose concentration was higher in FHA-EX+HA vs FHA-EX, 88.5 mg/dL (82.8–90 mg/dL) vs 83.5 mg/dL (78.8–86.3 mg/dL) (P=0.01) but not different from FHA-AN (P=0.31). Percentage of women with stress fractures was lower in FHA-EX+HA (4.5%) as compared to both FHA-EX (27.3%) and FHA-AN (50%); P=0.04 and 0.01 respectively. The LH/FSH ratio was weakly positively associated with serum glucose (adjusted r2=0.102; P=0.01) as well as with dual-energy X-ray absorptiometry spine score (adjusted r2=0.191; P=0.04) in the entire cohort.Conclusion: In a small cohort of female athletes with hyperandrogenism, a distinct reproductive hormone profile consisting of higher LH to FHS ratio may be associated with adverse metabolic health markers but improved skeletal health. Keywords: functional hypothalamic amenorrhea, hyperandrogenism, polycystic ovary syndrome, young athlete

The lipid phosphatase SHIP2 controls insulin sensitivity.

Insulin is the primary hormone involved in glucose homeostasis, and impairment of insulin action and/or secretion has a critical role in the pathogenesis of diabetes mellitus. Type-II SH2-domain-containing inositol 5-phosphatase, or 'SHIP2', is a member of the inositol polyphosphate 5-phosphatase family. In vitro studies have shown that SHIP2, in response to stimulation by numerous growth factors and insulin, is closely linked to signalling events mediated by both phosphoinositide-3-OH kinase and Ras/mitogen-activated protein kinase. Here we report the generation of mice lacking the SHIP2 gene. Loss of SHIP2 leads to increased sensitivity to insulin, which is characterized by severe neonatal hypoglycaemia, deregulated expression of the genes involved in gluconeogenesis, and perinatal death. Adult mice that are heterozygous for the SHIP2 mutation have increased glucose tolerance and insulin sensitivity associated with an increased recruitment of the GLUT4 glucose transporter and increased glycogen synthesis in skeletal muscles. Our results show that SHIP2 is a potent negative regulator of insulin signalling and insulin sensitivity in vivo.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe