MiR-186-5p negatively regulates CDCA3 to improve proliferation and inhibit apoptosis of islet β cells induced by high fat and high glucose

Objective To investigate whether miR-186-5p can regulate the proliferation and apoptosis of islet β-cells induced by high fat and high glucose through cell division cycle associated 3 protein (CDCA3). Methods Mouse pancreatic β-cell line NIT-1 was treated with high lipid and glucose to induce injury. CCK-8 assay and flow cytometry were employed to measure cell proliferation and apoptosis. The expression of Ki-67, PCNA, Bcl-2 and Bax at protein level was analyzed by Western blotting, while that of miR-186-5p and CDCA3 at mRNA level was determined by qRT-PCR. Bioinformatics and dual luciferase activity assay were used to predict and detect the targeting relationship between miR-186-5p and CDCA3. NIT-1 cells were transfected with miR-186-5p or si-CDCA3, and treated with high lipid and high glucose, and the effects on cell proliferation and apoptosis were observed. Results High lipid and high glucose significantly reduced the cell viability, protein levels of Ki-67, PCNA and Bcl-2, and mRNA level of miR-186-5p expression in NIT-1 cells, while significantly increased the cell apoptotic rate and Bax protein expression, as well as CDCA3 expression at mRNA and protein levels (P < 0.05). MiR-186-5p negatively regulates CDCA3 as a target. Overexpression of miR-186-5p or knockdown of CDCA3 dramatically improved the cell viability, increased the expression of Ki-67, PCNA, and Bcl-2 at protein level, while remarkably decreased the apoptotic rate and Bax protein expression in NIT-1 cells after the treatment of high lipid and high glucose (P < 0.05). Conclusion ConclusionmiR-186-5p can negatively regulate the expression of CDCA3 gene, and thus promote the proliferation of islet β cells induced by high fat and high glucose and inhibit the apoptosis, so as to protect the islet β cells against the damage induced by high fat and high glucose.