Growth Hormone-Binding Protein in Plasma Is Inversely Correlated to Placental Lactogen and Augmented with Increasing Body Mass Index in Healthy Pregnant Women and Women with Gestational Diabetes mellitus

Abstract

Pituitary growth hormone (GH), prolactin (PRL), placental lactogen (PL), insulin-like growth factor 1 (IGF-1) and GH-binding protein (GHBP) in plasma were determined in 12 women with gestational diabetes mellitus (GDM) and in 12 healthy pregnant women during a breakfast meal tolerance test. The women with GDM showed higher prepregnancy weight, body mass index (BMI), basal levels of glucose, insulin, and C peptide compared to the pregnant controls. No difference was found between the two groups in pituitary GH, PRL, PL and IGF-1 levels. Plasma levels of GHBP were higher in the women with GDM compared to pregnant controls. In all women there was an inverse correlation between PL and pituitary GH as well as between PL and GHBP, suggesting that PL inhibits pituitary GH secretion. A positive correlation between GHBP and BMI was found in all women, and the higher BMI in the GDM women seemed to be the cause of the higher GHBP levels in this group. In all women IGF-1, an indicator of the secretory activity of lactogenic hormones as well as of nutritional state, showed a positive correlation with the birth weights of the infants and was equally indicative in both groups.

Growth hormone binding protein and maternal body mass index in relation to placental growth hormone and insulin requirements during pregnancy in type 1 diabetic women

“…This association has also been observed in pregnancy [5,9,29], but interestingly, we observed that this association was lost in the third trimester, where GHBP levels decrease and the maternal BMI increase. The same tendency has been observed in normal individuals [9].…”

Clinical Recommendations for the Use of Islet Cell Autoantibodies to Distinguish Autoimmune and Non-Autoimmune Gestational Diabetes

“…Placental GH [17] and hPL [23] control embryo growth, likely via the opposing actions of insulin and insulin-like growth factors, inducing IR in humans [24]. hPL and prolactin increase maternal food intake by inducing central leptin resistance [17].…”

Physiology and pathophysiology of growth hormone-binding protein: Methodological and clinical aspects

“…A positive correlation to BMI is recorded in healthy adults [97,98,161,162], in obesity and underweight conditions [163][164][165][166][167][168], during pregnancy [169,170], and in children [150,[171][172][173][174]; in the elderly this association is less pronounced [144]. Application of more specific measures of body fat reveals a very strong positive correlation of GHBP levels to fat mass [150,162].…”

“…Placental GH is reported to correlate inversely to GHBP levels [203]. The relationship between GHBP and BMI is maintained during pregnancy, although the significance is less pronounced [169,170,202].…”

“…In children with newly diagnosed type 1 diabetes GHBP levels are significantly reduced [174,191,[272][273][274] and increase after initiation of insulin therapy [275,276]. In adults low levels are also found in type 1 diabetes [277,278] and in pregnant females with type 1 diabetes as well [170], whereas GHBP levels are increased in type 2 diabetics with hyperinsulinaemia [278,279], and in females with gestational diabetes [169]. In type 1 diabetes, portal insulin levels as well as peripheral GHBP levels are low; in type 2 diabetes, portal insulin levels and GHBP levels are high, and a positive correlation has been found between insulin levels and GHBP in type 2 diabetes [278,280].…”