Mir 20b 5p inhibitor

HRMECs (Angio-Proteomie, Boston, Mass, USA) were cultured in endothelial cell medium (ECM) with 5% fetal bovine serum, 1% endothelial cell growth supplement, and 1% penicillin/streptomycin solution (ScienCell Research Laboratories, Carlsbad, CA, USA) at 37 °C under 5% CO₂ atmosphere. Cells between passages three and eight were used in this study. Cells were treated with 5 mM glucose as a normal glucose (NG) control, 5 mM glucose plus 25 mM mannitol as an osmotic control, or 30 mM glucose as a high-glucose (HG) treatment. miR-20b-5p inhibitor, miR inhibitor negative control (NC), miR-20b-5p mimic, or miR mimic NC (RiboBio, Guangzhou, China) was transfected into HRMECs using Lipofectamine 3000 (Life Technologies, Carlsbad, CA, USA) according to the manufacturer's instructions. Small interfering BMP and activin membrane-bound inhibitor (siBAMBI) and siRNA NC synthesized by RiboBio were transfected using Lipofectamine RNAiMAX (Life Technologies). The human circDNMT3B sequence was inserted into the pLCDH-ciR vector, and then incorporated into a lentivirus by Geneseed Biotech (Guangzhou, China). To induce stable circDNMT3B-overexpressing HRMECs, the HRMECs at passage three were infected with lentivirus containing circDNMT3B or ciR NC (empty vector). All sequences used in this study are listed in Supplementary Table S1.