Figure 4

Effects of miR-375, miR-30a, and miR-34a expression of INS-1 cells.

The expression levels of miRNAs were analyzed by qRT-PCR assays in islets treated with 11.1 (control) and 25 mmol/l glucose for 48 h (A), as well as in INS-1 cells treated with 5.5 (control) and 25 mmol/l glucose for 12 h (B). The expressions of miR-375, miR-30a and miR-34a were determined after 24 h miRNA transfection (C). Cellular apoptosis was analyzed 48 h after transfection (D). A vector (white bar) or NICD1 (black bar) plasmid was co-transfected with the indicated miRNAs or NC mimics for 48 h and the cells were then collected for PI staining and analyzed by flow cytometry (E). A vector or NICD1 plasmid was co-transfected with the indicated miRNAs or NC mimics for 48 h and TUNEL assay was carried out to detect dead cells. Scale bars = 40 μm (F). Quantitative result of TUNEL assay was analyzed. Data were obtained from 8 scans in each group (G). Data shown are means ± SEM and representative of three separate experiments. (A–D) *p < 0.05 or **p < 0.01 vs. control. (E,G) **p < 0.01 vs. NC + vector, and ^#p < 0.05 or ^##p < 0.01 vs. relative miRNA + vector.