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Aim To explore the effect of boschniakia rossica polysaccharides ( BRPS ) on cardiomyocyte damage induced by hypoxia/reoxygenation (H/R) and its possible mechanism. Methods H/R was used to induce rat cardiomyocyte H9c2 to establish a cell inju¬ry model, and different doses of BRPS were used to treat H9c2 cells. ELISA method was used to detect the level of MDA and the activity of SOD and GSH-Px. Flow cytometry was used to detect the rate of apopto-sis. qRT-PCR was used to detect the expression of miR-302a-3p. anti-miR-NC and anti-miR-302a-3p were respectively transfected into H9c2 cells and then subjected to H/R treatment. miR-NC and miR-302a-3p mimics were respectively transfected into H9c2 cells and treated with 100 mg • L
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@#Introduction: The polycistronic miR-302 cluster encodes five miRNA genes that have an important role in the regulation of embryonic stem cell function. Studies showed that the miR-302 cluster can reprogram both mouse and human fibroblasts to induced pluripotent stem cells (iPSCs) with high efficiency. The aim of this study was to generate an inducible lentivirus that expresses miR-302 cluster in order to further investigate somatic cell reprogramming by these miRNAs. Materials and Methods: The miR-302 cluster was amplified by polymerase chain reaction technique from human genomic DNA and was ligated into pTRIPz, an inducible lentiviral vector. Results: MRC5 fibroblasts and HEK293 (human embryonic kidney) cells were infected with pTRIPz-302 cluster lentivirus and the family of 302 miRNAs were strongly expressed in HEK293 cells but lowly expressed in MRC5 fibroblasts. When cultured in hESC conditions, MRC5 cells expressed only low levels of DNMT3B, Nanog, Oct4 and Lin28 and failed to show stem cell induction. The red fluorescent expression seen in the majority of MRC5 cells, indicated that the rate of infection by lentivirus was efficient. Discussion: The efficiency of reprogramming may be improved perhaps by either using a different cell type or a high expression vector with a different type of promoter.
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Objective: To investigate the effects of the combination of Celastrus orbiculatus extracts and miR-302 on proliferation, invasion and migration of human esophageal cancer cells and the regulation of PI3K/Akt signaling pathway. Methods Quantitative RT-PCR was used to detect the expression of miR-302 in human normal esophageal epithelial cells Het-1A and different esophageal cancer cell lines. The miR-302 mimic and negative control mimic control were transfected into human esophageal cancer TE-1 cells, and qPCR was used to detect the expression of miR-302 in TE-1 cells after plasmid transfection. TE-1 cells were treated with C. orbiculatus extracts alone and combination treatment. The proliferation of TE-1 cells was detected by CCK-8 assay. The invasion and migration of TE-1 cells were detected by Transwell assay. Western blot analysis of the expression of related protein in the PI3K/Akt signaling pathway was carried out. Results: The expression of miR-302 in esophageal cancer cell lines was significantly lower than that in esophageal epithelial cells (P < 0.05). Transfection of miR-302 mimic could effectively increase the expression of miR-302 in TE-1 cells (P < 0.05). The use of C. orbiculatus extracts alone or overexpression of miR-302 inhibited proliferation, invasion and migration of esophageal cancer TE-1 cells (P < 0.05), down-regulated PI3K and p-Akt protein expression; Combination treatment had more significant effect on inhibiting proliferation, invasion and migration of TE-1 cells and down-regulating protein expression of PI3K and p-Akt (P < 0.05). Conclusion: Celastrus orbiculatus extracts combined with miR-302 can synergistically inhibit the proliferation, invasion, and migration of esophageal cancer TE-1 cells, and its mechanism may be related to the inhibition of PI3K/Akt signaling pathway activation.
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Objective To explore effect of miR‐302a on proliferation and apoptosis in folate deficiency mouse embryonic stem cell (mESC) .Methods The cases were divided into complete culture medium group (control group) ,folate‐deficient culture medi‐um group (folate‐deficient group) ,folate‐deficient culture medium plus miR‐302a mimic group (miR‐302a group) .The expression of miR‐302a was examed by RT‐PCR in control group and folate‐deficient group .To construct miR‐302a mimic and then was trans‐fected into the folate‐deficient culture medium mESC .Effect of miR‐302a mimic on mESC viability was detected by MTT assay ,the effect of miR‐302a mimic on mESC apoptosis was examed by Annexin V‐FITC/PI flow dual‐staining method ,the effect of miR‐302a mimic on mESC cycle was examed by flow cytometry .The activation of phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) and expression of CyclinD1 ,p21 and p27 was assayed by Western blot . Results The expression of miR‐302a was lower in folate‐deficient group(P<0 .01) .Compared with control group ,the viability of mESC was lower ,the apoptosis of mESC was higher ,the cell cycle was arrested in G1 phase ,the level of phosphorylation of AKT and mTOR was lower ,the expression of CyclinD1 was lower ,the expression of p21 and p27 was higher in folate‐deficient group , with statistical significance (P<0 .01) .Compared with folate‐deficient group ,the viability of mESC was higher ,the apoptosis of mESC was lower ,G1 phase was shortened ,the level of phosphorylation of AKT and mTOR was higher ,the expression of CyclinD1 was higher ,the expression of p21 and p27 was lower in miR‐302a group with statistical significance (P<0 .01) .Conclusion These results suggested miR‐302a exerted anti‐apoptosis and promote cell proliferation in folate‐deficient culture medium ,which might be related to PI3K/AKT/mTOR signal pathway .