Ilaria Floris1, Betty Descamps1, Antonella Vardeu1, Tijana Mitić1, Anna Maria Posadino1, Saran Shantikumar1, Graciela Sala-Newby1, Gianpiero Capobianco1, Giuseppe Mangialardi1, Lynsey Howard1, Salvatore Dessole1, Raul Urrutia1, Gianfranco Pintus1, Costanza Emanueli2. 1. From the Bristol Heart Institute, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom (I.F., B.D., A.V., T.M., S.S., G.S.-N., G.M., L.H., C.E.); Laboratory of Vascular Biology, Department of Biomedical Science (I.F., A.V., M.P., G.P.) and Department of Obstetrics and Gynecology Unit (G.C., S.D.), University of Sassari, Sassari, Italy; Laboratory of Epigenetics and Chromatin Dynamics, Mayo Clinic, Rochester, MN (R.U.); and National Heart and Lung Institute, Imperial College London, London, United Kingdom (C.E.). 2. From the Bristol Heart Institute, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom (I.F., B.D., A.V., T.M., S.S., G.S.-N., G.M., L.H., C.E.); Laboratory of Vascular Biology, Department of Biomedical Science (I.F., A.V., M.P., G.P.) and Department of Obstetrics and Gynecology Unit (G.C., S.D.), University of Sassari, Sassari, Italy; Laboratory of Epigenetics and Chromatin Dynamics, Mayo Clinic, Rochester, MN (R.U.); and National Heart and Lung Institute, Imperial College London, London, United Kingdom (C.E.). Costanza.Emanueli@bristol.ac.uk.
Abstract
OBJECTIVE: Gestational diabetes mellitus (GDM) produces fetal hyperglycemia with increased lifelong risks for the exposed offspring of cardiovascular and other diseases. Epigenetic mechanisms induce long-term gene expression changes in response to in utero environmental perturbations. Moreover, microRNAs (miRs) control the function of endothelial cells (ECs) under physiological and pathological conditions and can target the epigenetic machinery. We investigated the functional and expressional effect of GDM on human fetal ECs of the umbilical cord vein (HUVECs). We focused on miR-101 and 1 of its targets, enhancer of zester homolog-2 (EZH2), which trimethylates the lysine 27 of histone 3, thus repressing gene transcription. EZH2 exists as isoforms α and β. APPROACH AND RESULTS: HUVECs were prepared from GDM or healthy pregnancies and tested in apoptosis, migration, and Matrigel assays. GDM-HUVECs demonstrated decreased functional capacities, increased miR-101 expression, and reduced EZH2- β and trimethylation of histone H3 on lysine 27 levels. MiR-101 inhibition increased EZH2 expression and improved GDM-HUVEC function. Healthy HUVECs were exposed to high or normal d-glucose concentration for 48 hours and then tested for miR-101 and EZH2 expression. Similar to GDM, high glucose increased miR-101 expression. Chromatin immunoprecipitation using an antibody for EZH2 followed by polymerase chain reaction analyses for miR-101 gene promoter regions showed that both GDM and high glucose concentration reduced EZH2 binding to the miR-101 locus in HUVECs. Moreover, EZH2-β overexpression inhibited miR-101 promoter activity in HUVECs. CONCLUSIONS: GDM impairs HUVEC function via miR-101 upregulation. EZH2 is both a transcriptional inhibitor and a target gene of miR-101 in HUVECs, and it contributes to some of the miR-101-induced defects of GDM-HUVECs.
OBJECTIVE: Gestational diabetes mellitus (GDM) produces fetal hyperglycemia with increased lifelong risks for the exposed offspring of cardiovascular and other diseases. Epigenetic mechanisms induce long-term gene expression changes in response to in utero environmental perturbations. Moreover, microRNAs (miRs) control the function of endothelial cells (ECs) under physiological and pathological conditions and can target the epigenetic machinery. We investigated the functional and expressional effect of GDM on human fetal ECs of the umbilical cord vein (HUVECs). We focused on miR-101 and 1 of its targets, enhancer of zester homolog-2 (EZH2), which trimethylates the lysine 27 of histone 3, thus repressing gene transcription. EZH2 exists as isoforms α and β. APPROACH AND RESULTS: HUVECs were prepared from GDM or healthy pregnancies and tested in apoptosis, migration, and Matrigel assays. GDM-HUVECs demonstrated decreased functional capacities, increased miR-101 expression, and reduced EZH2- β and trimethylation of histone H3 on lysine 27 levels. MiR-101 inhibition increased EZH2 expression and improved GDM-HUVEC function. Healthy HUVECs were exposed to high or normal d-glucose concentration for 48 hours and then tested for miR-101 and EZH2 expression. Similar to GDM, high glucose increased miR-101 expression. Chromatin immunoprecipitation using an antibody for EZH2 followed by polymerase chain reaction analyses for miR-101 gene promoter regions showed that both GDM and high glucose concentration reduced EZH2 binding to the miR-101 locus in HUVECs. Moreover, EZH2-β overexpression inhibited miR-101 promoter activity in HUVECs. CONCLUSIONS: GDM impairs HUVEC function via miR-101 upregulation. EZH2 is both a transcriptional inhibitor and a target gene of miR-101 in HUVECs, and it contributes to some of the miR-101-induced defects of GDM-HUVECs.
Authors: Pandora L Wander; Edward J Boyko; Karin Hevner; Viraj J Parikh; Mahlet G Tadesse; Tanya K Sorensen; Michelle A Williams; Daniel A Enquobahrie Journal: Diabetes Res Clin Pract Date: 2017-07-25 Impact factor: 5.602
Authors: Quincy A Hathaway; Mark V Pinti; Andrya J Durr; Shanawar Waris; Danielle L Shepherd; John M Hollander Journal: Am J Physiol Heart Circ Physiol Date: 2017-10-06 Impact factor: 4.733