Characterizing the Effects of Diabetes and Obesity on Insulin and Leptin Levels amongst Pregnant Women.

Abstract

In this study, we assess the impact of obesity and diabetes on maternal brain and periphery, as well as fetal exposure to insulin and leptin, and two hormones that play an important role in regulating energy homeostasis. Fasting maternal plasma, fetal cord vein and artery plasma, and maternal cerebrospinal fluid (CSF) were collected in 37 women (12 lean, nondiabetic [prepregnancy body mass index (BMI): 22.9 ± 1.7 kg/m2]; 12 overweight/obese nondiabetic [BMI: 37.8 ± 7.3 kg/m2]; 13 gestational/type 2 diabetes mellitus [BMI: 29.8 ± 7.3 kg/m2]) with uncomplicated singleton pregnancies undergoing elective Cesarean delivery. HbA1C, insulin, glucose, and leptin levels were measured. Compared with lean mothers, mothers with obesity and diabetes mellitus (DM) had significantly lower CSF-to-plasma ratios of insulin. Moreover, mothers with obesity and DM had significantly lower cord arterial and cord venous to maternal plasma ratios of insulin, but not leptin, compared with lean mothers. There were no differences in CSF and cord blood insulin and leptin levels between obese and DM mothers. Compared with lean individuals, mothers with obesity and DM have relative deficiencies in insulin exposure. The patterns observed in mothers with obesity and diabetes were similar highlighting the importance of the maternal metabolic environment in obesity and suggesting obese patients warrant further clinical focus.