Female androgen excess and male androgen deficiency manifest with an overlapping adverse metabolic phenotype, including abdominal obesity, insulin resistance, type 2 diabetes mellitus, non-alcoholic fatty liver disease and an increased risk of cardiovascular disease. Here, we review the impact of androgens on metabolic target tissues in an attempt to unravel the complex mechanistic links with metabolic dysfunction; we also evaluate clinical studies examining the associations between metabolic disease and disorders of androgen metabolism in men and women. We conceptualise that an equilibrium between androgen effects on adipose tissue and skeletal muscle underpins the metabolic phenotype observed in female androgen excess and male androgen deficiency. Androgens induce adipose tissue dysfunction, with effects on lipid metabolism, insulin resistance and fat mass expansion, while anabolic effects on skeletal muscle may confer metabolic benefits. We hypothesise that serum androgen concentrations observed in female androgen excess and male hypogonadism are metabolically disadvantageous, promoting adipose and liver lipid accumulation, central fat mass expansion and insulin resistance.
Lina Schiffer, Punith Kempegowda, Wiebke Arlt and Michael W O’Reilly
Michael W O'Reilly, Gloria Avalos, Michael C Dennedy, Eoin P O'Sullivan and Fidelma Dunne
Gestational diabetes (GDM) is associated with adverse fetal and maternal outcomes, and identifies women at risk of future type 2 diabetes mellitus (T2DM). Breast-feeding may improve post partum maternal glucose tolerance. Our objective was to identify the prevalence of post partum dysglycemia after GDM, to delineate associated factors and to examine the effect of lactation on post partum glucose tolerance.
We compared post partum 75 g oral glucose tolerance test (OGTT) results from 300 women with GDM and 220 controls with normal gestational glucose tolerance (NGT) in five regional centers. Breast-feeding data was collected at time of OGTT.
Post partum OGTT results were classified as normal (fasting plasma glucose (FPG) <5.6 mmol/l, 2 h <7.8 mmol/l) and abnormal (impaired fasting glucose (IFG), FPG 5.6–6.9 mmol/l; impaired glucose tolerance (IGT), 2 h glucose 7.8–11 mmol/l; IFG+IGT; T2DM, FPG ≥7 mmol/l±2 h glucose ≥11.1 mmol/l). Binary logistic regression was used to identify factors predictive of persistent hyperglycemia.
Five hundred and twenty women were tested; six (2.7%) with NGT in pregnancy had post partum dysglycemia compared with 57 (19%) with GDM in index pregnancy (P<0.001). Non-European ethnicity (odds ratio (OR) 3.40; 95% confidence interval (CI) 1.45–8.02, P=0.005), family history of T2DM (OR 2.14; 95% CI 1.06–4.32, P=0.034), and gestational insulin use (OR 2.62; 95% CI 1.17–5.87, P=0.019) were associated with persistent dysglycemia. The prevalence of persistent hyperglycemia was significantly lower in women who breast-fed vs bottle-fed post partum (8.2 vs 18.4%, P<0.001).
Non-European ethnicity, gestational insulin use, family history of T2DM, and elevated body mass index were associated with persistent dysglycemia after GDM. Breast-feeding may confer beneficial metabolic effects after GDM and should be encouraged.