A Randomised, Controlled Study of Different Glycaemic Targets during Gestational Diabetes Treatment: Effect on the Level of Adipokines in Cord Blood and ANGPTL4 Expression in Human Umbilical Vein Endothelial Cells

Our aim was to study the expression of adipokine-encoding genes (leptin, adiponectin, and angiopoietin-like protein 4 (ANGPTL4)) in human umbilical vein endothelial cells (HUVECs) and adipokine concentration in cord blood from women with gestational diabetes mellitus (GDM) depending on glycaemic targets. GDM patients were randomised to 2 groups per target glycaemic levels: GDM1 (tight glycaemic targets, fasting blood glucose < 5.1 mmol/L and <7.0 mmol/L postprandial, N = 20) and GDM2 (less tight glycaemic targets, <5.3 mmol/L and < 7.8 mmol/L, respectively, N = 21). The control group included 25 women with normal glucose tolerance. ANGPTL4 expression was decreased in the HUVECs from GDM patients versus the control group (23.11 ± 5.71, 21.47 ± 5.64, and 98.33 ± 20.92, for GDM1, GDM2, and controls; p < 0.001) with no difference between GDM1 and GDM2. The level of adiponectin gene expression was low and did not differ among the groups. Leptin gene expression was undetectable in HUVECs. In cord blood, leptin/adiponectin ratio (LAR) was increased in GDM2 compared to controls and GDM1 (p = 0.038) and did not differ between GDM1 and controls. Tight glycaemic targets were associated with normalisation of increased LAR in the cord blood. ANGPTL4 expression was downregulated in HUVECs of newborns from GDM mothers and was not affected by the intensity of glycaemic control.

Lamin A/C mutation associated with lipodystrophy influences adipogenic differentiation of stem cells through interaction with Notch signaling

Lamins A and C are involved in many cellular functions, owing to its ability to bind chromatin and transcription factors and affect their properties. Mutations of the LMNA gene encoding lamin A/C affect differentiation capacity of stem cells. However, the signaling pathways involved in interactions with lamins during cellular differentiation remain unclear. Lipodystrophy associated with LMNA mutation R482L causes loss of fat tissue. In this study we investigated the role of LMNA mutation R482L in modulating Notch signaling activity in the adipogenic differentiation of mesenchymal stem cells. Notch was activated using lentiviral Notch intracellular domain. Activation of Notch was estimated through the expression of Notch-responsive genes by qPCR and by activation of a luciferase CSL-reporter construct. The effect of LMNA mutation on Notch activation and adipogenic differentiation was analyzed in cells bearing lentiviral LMNA WT or LMNA R482L. We show that, when Notch is activated, LMNA R482L contributes to down-regulation of Notch activation in undifferentiated and differentiated cells, and decreases adipogenic differentiation. Thus, lamin A/C interacts with Notch signaling, thereby influencing cellular differentiation, and point mutation in LMNA could halt this interaction.