MicroRNA-130a regulates autophagy of endothelial progenitor cells through Runx3.

Dysfunction of endothelial progenitor cells (EPC) contribute to diabetic vascular disease. MicroRNAs (miRNAs) are key regulators of diverse cellular processes, including angiogenesis. We recently reported that downregulated miR-130a in patients with Type 2 diabetes mellitus (DM) results in EPC dysfunction, including increased apoptosis, likely via its target runt-related transcription factor 3 (Runx3). However, whether miR-130a affects the autophagy of EPC is unknown. The aim of the present study was to explore the effects of miR-130a on the autophagy and cell death of EPC, as well as their expression of Beclin 1 (BECN1; an initiator of autophagosome formation) and the anti-apoptotic protein Bcl2 (which binds to and inactivates BECN1), and the role of Runx3 in mediating these effects. The EPC were cultured from peripheral blood mononuclear cells of diabetic patients and non-diabetic controls. Cells were transfected with an miR-130a inhibitor, or mimic-miR-130a or mimic-miR-130a plus lentiviral vector expressing Runx3 to manipulate miR-130a and/or Runx3 levels. The number of autophagosomes was counted under transmission electron microscopy and cell death was examined by flow cytometry. The mRNA expression of Beclin1 was measured by real-time polymerase chain reaction and the protein expression of Beclin1 and Bcl2 was determined by western blotting. Both the number of autophagosomes and Beclin1 expression were increased in EPC from patients with DM. Inhibition of miR-130a increased the number of autophagosomes and Beclin1 expression, but attenuated Bcl2 expression. Overexpression of miR-130a decreased the number of autophagosomes, cell death and Beclin1 expression, but promoted Bcl2 expression; these effects were mediated by Runx3. In conclusion, miR-130a is important for maintaining normal autophagy levels and promoting the survival of EPC via regulation of Bcl-2 and Beclin1 expression, via Runx3. MiR-130a may be a regulator linking apoptosis and the autophagy of EPC.

Xu Q ，Meng S ，Liu B ，Li MQ ，Li Y ，Fang L ，Li YG ... -  《-》

Downregulation of microRNA-130a contributes to endothelial progenitor cell dysfunction in diabetic patients via its target Runx3.

Meng S ，Cao J ，Zhang X ，Fan Y ，Fang L ，Wang C ，Lv Z ，Fu D ，Li Y ... -  《PLoS One》

Downregulation of microRNA-126 in endothelial progenitor cells from diabetes patients, impairs their functional properties, via target gene Spred-1.

Diabetes mellitus (DM) adversely affects the number and function of circulating endothelial progenitor cells (EPCs). Consequently, there is also a reduction in the repair mechanism of these cells, which is a critical and initiating factor in the development of diabetic vascular disease. The aim of the present study was to analyze miR expression profiles in EPCs from patients with DM and choose the most significantly regulated miR to study its possible role on EPC dysfunction and elucidate its mechanism of action. EPCs were collected from subjects with Type II DM and non-diabetic control subjects. Total RNA was harvested from EPCs, and a total of 5 candidate miRNAs were identified by microarray screening and were quantified by TaqMan real-time PCR. Lentiviral vectors expressing miR-126 and miR-126 inhibitor (anti-miR-126) were transfected into EPCs, and the EPC colony-forming capacity, proliferation activity, migratory activity, differentiation capacity, and apoptotic susceptibility were determined and Western Blotting and mRNA real-time PCR analyses were performed. To study the mechanisms, lentiviral vectors expressing Spred-1 and a short interfering RNA (siRNA) targeting Spred-1 were prepared. Five miRs were aberrantly downregulated in EPCs from DM patients. These miRs included miR-126, miR-21, miR-27a, miR-27b and miR-130a. Anti-miR-126 inhibited EPC proliferation, migration, and enhanced apoptosis. Restored miR-126 expression in EPCs from DM promoted EPC proliferation, migration, and inhibited EPC apoptosis ability. Despite this, miR-126 had no effect on EPC differentiation. miR-126 overexpression significantly downregulated Spred-1 in EPCs. The knockdown of Spred-1 expression in EPCs from DM promoted proliferation, migration, and inhibited apoptosis of the cells. The signal pathway of miR-126 effecting on EPCs is partially mediated through Ras/ERK/VEGF and PI3K/Akt/eNOS regulation. This study provides the first evidence that miR-126 is downregulated in EPCs from diabetic patients, and impairs EPCs-mediated function via its target, Spred-1, and through Ras/ERK/VEGF and PI3K/Akt/eNOS signal pathway.

Meng S ，Cao JT ，Zhang B ，Zhou Q ，Shen CX ，Wang CQ ... -  《-》

MicroRNA-130a Targets MAP3K12 to Modulate Diabetic Endothelial Progenitor Cell Function.

The aim of the present study was to explore the influence of microRNA (miR)-130a dysregulation on the JNK signal pathway through its target MAP3K12 in diabetic endothelial progenitor cells (EPCs). The expression of miR-130a was compared between diabetic and normal EPCs. Computational target prediction was performed to identify MAP3K12 as a functionally relevant target of miR-130a in EPCs. The role of miR-130a was investigated regarding its anti-apoptotic effects and its role on the regulation of EPC function was evaluated through the negative regulation of the JNK signal pathway MiR-130a expression was significantly downregulated in diabetic EPCs, and cell proliferation was reduced in EPCs under high glucose condition. miR-130a inhibited the JNK pathway by targeting MAP3K12, contributing to its anti-apoptotic effect and the maintenance of EPC function. In diabetic EPCs, high glucose affects the expression of miR-130a, inducing sustained JNK activation and promoting EPC apoptosis and dysfunction. Downregulation of miR-130a may underlie endothelial dysfunction in diabetes through the activation of JNK signal pathway.

Ye M ，Li D ，Yang J ，Xie J ，Yu F ，Ma Y ，Zhu X ，Zhao J ，Lv Z ... -  《-》

Targeting of RUNX3 by miR-130a and miR-495 cooperatively increases cell proliferation and tumor angiogenesis in gastric cancer cells.

Lee SH ，Jung YD ，Choi YS ，Lee YM ... -  《Oncotarget》