ObjectiveTo explore the effect of expression of miRNA-21 on bone marrow mesenchymal stem cells (BMSCs).MethodsIn this study, flow cytometry was used to identify the surface-associated antigens of BMSCs. The 10 μmol/L 5-azacytidine was used to induce BMSCs to differentiate to cardiomyocyte-like cells. Immunofluorescence was used to detect the expression of troponin I (cTnI). The samples were assigned to 3 groups: a blank group, a miRNA-21 mimic group, and a negative control (NC) group. The proliferation of BMSCs was detected by methyl thiazolylte-trazolium (MTT), the apoptosis of BMSCs was analyzed by flow cytometry. Western-blotting was used to identify the expression of cTnI and myod in the BMSCs.ResultsThe proliferation of BMSCs was increased, because of the over expression of miRNA-21. But the apoptotic rate of the BMSCs was slower in the miRNA-21 group, on account of the expression of miRNA-21 was higher than that in the NC group and the CK group. The expression of cTnI in the miRNA-21 group was higher than that in the NC group or the CK group.ConclusionThe results suggest that the up-regulation of miRNA-21 enhances proliferation of BMSCs, reduces the apoptosis of BMSCs. miRNA-21 promotes the differentiation of BMSCs, which may pave the way for the treatment directed toward restoring miRNA-21 function for myocardial ischemia.
ObjectiveTo investigate the regulatory effect of miRNA-21-5p (miR-21) on spinal fibroblasts, and to explore the mechanism of miR-21 related pathological process of spinal cord injury.MethodsSpinal cord fibroblasts were identified by immunofluorescence. Spinal fibroblasts damage model was established by scratch method. Quantitative real-time polymerase chain reaction (RT-PCR) was used to determine the relative expression of miR-21 and fibrosis-related genes in spinal cord fibroblasts after injury. The expression of miR-21 in spinal cord fibroblasts was up-regulated and down-regulated by using miR-21 mimics/inhibitor, and the expression levels of apoptosis and proliferation-related proteins were detected by Western Blot (WB).ResultsThe expression of miR-21 and fibrosis-related genes were increased after spinal cord fibroblast scratch (P<0.05). Up-regulation of the miR-21 can increase the expression of apoptosis-related genes in fibroblasts (P<0.05), and vice versa. The proliferation of fibroblasts was consistent with the expression of miR-21, while the apoptosis of fibroblasts was contrary to the expression of miR-21.ConclusionsmiR-21 enhanced the fibrosis and proliferation, inhibited the apoptosis of spinal cord fibroblasts after mechanical injury. This indicates that miR-21 is closely related with the formation of fibrotic scar after spinal cord injury, which also providesa potential therapeutic target for spinal cord injury.
ObjectiveTo investigate the expression level of exosome microRNA-21 (miRNA-21) in the bile and its clinical diagnostic value for the patients with cholangiocarcinoma. MethodsIn this study, 45 cases of cholangiocarcinoma admitted to Dongfeng General Hospital from August 2019 to December 2021 and met the inclusion criteria were selected and 35 patients with benign diseases of bile duct (choledocholithiasis or benign stricture of bile duct) during the same period were selected as control. The exosome in the bile was extracted by hypervelocity centrifugation method and identified. The exosome miRNA was extracted from the bile using a kit, then the expression level of miRNA-21 was detected by real-time fluorescent quantitative PCR. The diagnostic value of exosome miRNA-21 in the bile for cholangiocarcinoma was analyzed by receiver operating characteristic curve (ROC). ResultsThe isolated exosome in the bile conformed to the characteristics of recognized exosome and the concentration was higher. The average expression level of exosome miRNA-21 in the bile of the patients with cholangiocarcinoma was statistically higher than that in the patients with benign diseases of bile duct (59.45 verses 25.41, t=3.445, P<0.001). The area under the ROC curve was 0.715 [95%CI (0.602, 0.827), P=0.001]. The sensitivity and specificity of miRNA-21 in the diagnosis of cholangiocarcinoma were 75.6% and 62.9%, respectively. ConclusionFrom the results of this study, exosome miRNA-21 expression in bile is higher and it may be a potential early diagnostic marker for patients with cholangiocarcinoma.