microRNA-124与糖尿病肾脏疾病

microRNA(miRNA)广泛存在于真核生物体内,参与蛋白质的转录和转录后的调控.miRNA具有高度进化保守性及组织特异性,在生物的生长发育、细胞分化、疾病的发展过程中起作用.miRNA-124是microRNAs家族的重要成员,近年研究显示,miRNA-124能够作用于整合素,进而影响肾脏纤维化进程,可能作用于Rho/Rho相关蛋白激酶信号通路,起到保护肾小球滤过屏障的作用,能够作用于信号转导与转录激活因子3、Toll样受体、磷脂酰肌醇3激酶/蛋白激酶B信号通路调节炎性反应,可能成为糖尿病肾脏疾病诊断和治疗的新靶点.     

Clinical significance of serum miR-21 in old and young patients with acute myocardial infarction

Background There may be dysregulation of circulating microRNAs in acute myocardial infarction （AMI）, which is an aging-related process. However, the difference between young and elderly people in expression level of circulating miR-21 in AMI patients has not been investigated. Methods The study included 72 consecutive patients with AMI. The group I consisted of 43 patients aged equal to or above 65 years and the group II consisted of 29 patients aged equal to or below 45 years. Real-time RT-PCR was applied to detect serum miR-21 expression levels at the time of mechanical reperfusion and 12 h, D1, D3 and D7 after PCI, respectively. Results The expression level of miR-21 in AMI patients increased markedly 12 h after PCI and reached the peak at D1 after PCI in both groups. There was no difference of miR-21 expression between Group I and U at the time of mechanical reperfusion （5.12 _＋ 0.73 vs. 4.98 ＋ 0.87） and D7 after PCI （1.28 __ 0.75 vs. 1.94 ＋ 0.89）, However, group I patients exhibited higher miR-21 expression level than group I1 at 12 h （7.96 ＋ 0.78 vs. 4.23 0.77, P 〈 0.05）, D1（9.32 __ 0.89 vs. 6.12 __ 0.92, P 〈 0.05） and D3 （4.78 __ 0.91 vs. 2.97 _＋ 0.77, P 〈 0.05） after PCI, respectively. Conclusion Our data reveal an increase of miR-21 in patients with AMI may be a mechanism of myocardial ischemia reperfusion injury. The expression of miR-21 was related to the development and progression of AMI, and there is an age-related change in the expression of miR-21 in acute myocardial infarction patients.     

Association between microRNA-527 and glypican-3 in hepatocellular carcinoma

The present study aimed to identify the specific microRNAs (miRNAs/miRs) and their corresponding target genes involved in hepatocellular carcinomas (HCCs). Microarray analysis was performed to examine the miRNA expression profiles of four paired HCC and corresponding non-cancerous (N) liver tissues using 985 miRNA probes. The Human miRNA Target database was used to identify the target genes of differentially expressed miRNAs between the HCC and N tissues. The protein expression levels of target genes in the HCC tissues and cell lines were evaluated using western blotting. miRNA-mediated suppression of target gene expression was evaluated by transiently transfecting the miRNA into the HCC cell lines. Of the 985 miRNAs evaluated, four miRNAs were differentially expressed (three upregulated and one downregulated miRNAs). Of these four miRNAs, miRNA-527 was highly downregulated in the HCC tissues. Glypican-3 (GPC-3) was predicted as a target gene of miRNA-527. Western blotting revealed that GPC-3 protein is highly expressed in the HCC tissues and HCC cell lines compared with N and normal cell lines. Transfection with miR-527 resulted in suppression of GPC-3 protein expression in the Cos7 cells. Furthermore, transfection with miR-527 also inhibited the intrinsic expression of GPC-3 in the Huh-7 cell line. This indicated that miR-527 in the HCC tissues may be an important novel miRNA that targets the GPC-3 gene expression. GPC-3, whose expression is regulated by miR-527, may be involved in the development and progression of HCC.     

微小RNA-27 a对黑色素瘤WM239细胞增殖和凋亡的影响

目的：探讨微小RNA-27a（ miR-27a）模拟物和抑制物转染黑色素瘤WM239细胞后对细胞增殖和凋亡的影响。方法将miR-27a模拟物、抑制物及其阴性对照转染WM239细胞,荧光显微镜观察转染效率,实时荧光定量PCR检测相应的微小RNA,四甲基偶氮唑盐（ MTT）法检测细胞增殖,流式细胞仪检测细胞凋亡和细胞周期。结果细胞转染效率为80%~90%。转染miR-27a模拟物后,细胞内miR-27a表达量明显上升（2-△△CT值为26.98±0.01）,与正常对照组相比差异有统计学意义（ t＝－1123.67,P＝0.00）;转染miR-27a抑制物后,细胞中miR-27a的表达量下降（2-△△CT值为0.96±0.02）,与正常对照组相比差异无统计学意义（t＝4.04,P＝0.06）。转染miR-27a模拟物后,细胞增殖受到明显抑制,与正常对照组相比差异具有统计学意义[72 h吸光度（0.45±0.02）∶（0.72±0.01）,F＝129.56,P﹤0.05]。miR-27a模拟物组G0-G1期的细胞比例升高[（74.83±1.46）∶（63.73±1.25）,F＝30.33,P﹤0.05],S期和G2-M期细胞比例减少[（21.33±1.75）∶（27.50±1.25）,F＝14.98,P﹤0.05;（3.90±1.31）∶（8.80±2.10）,F＝3.66,P﹤0.05];模拟物组细胞凋亡率与正常对照组相比明显增加[（29.67±0.91）%∶（1.44±0.85）%, F＝530.90,P﹤0.01];而抑制物组对细胞周期和凋亡无明显作用。结论 miR-27a抑制黑色素瘤细胞增殖,具有抑瘤作用,这与其促进细胞凋亡,阻滞细胞周期于G0-G1期相关。