Abstract： Objective To observe the expression changes of microRNA 1 （miRNA-1） and microRNA 21（miRNA-21） after ischemic preconditioning （IPC）, ischemic postconditioning （IPO） and remote ischemic preconditioning （RIPC）in an ischemia-reperfusion rat heart model in vitro, as well as the expression of their target protein heat shock protein 70 （HSP70） and programmed cell death 4 （PDCD4）, and evaluate whether miRNA are involved in endogenous cardio-protective mechanism. Methods The Langendorff-perfused Sprague-Dawley rat hearts were randomly assigned into one of the four groups, control group （CON group, n=12）, ischemia preconditioning group （IPC group， n=12）?, ischemia postconditioning group （IPO group， n=12） and remote ischemia preconditioning group （RIPC group，n=12）. Cardiac function was digitalized and analyzed. The expression of HSP70, PDCD4, B-cell lymphoma/leukemia-2 （Bcl-2） and Bax was detected by Western blotting. The expression of miRNA-1 and miRNA-21 was detected by real-time reverse transcriotion-polymerase chain reaction （RT-PCR）. Assessment of cardiac infarct size and myocardial apoptosis was determined using triphenyltetrazolium chloride （TTC） assay and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay （TUNEL） assay respectively. Results The expressions of miRNA-1 and miRNA-21 were up-regulated in IPC group, but the expression of miRNA-1 was down-regulated in RIPC group and IPO group （P＜0.05）. The expressionsof PDCD4, HSP70 and Bax were down-regulated in ‘conditioning’ groups compared with CON group （P＜0.05）. The expression of Bcl-2 was not statistically different among the four groups. The infarct size and the myocardial apoptosis in ‘conditioning’ hearts were significantly decreased compared with CON group （P＜0.05）. Conclusion The expressions of the miRNA-1 and miRNA-21 are different in IPC, RIPC and IPO groups, and their target proteins are not inversely correlated with the miRNAs in all the ‘conditioning’ groups.
Objective To search for the key microRNAs (miRNAs) involved in myocardial fibrosis in hypertrophic cardiomyopathy, and to further explore the mechanisms involved in the regulation of myocardial fibrosis. MethodsForty-two patients with hypertrophic cardiomyopathy diagnosed and treated surgically in West China Hospital of Sichuan University from January 2014 to June 2018 were selected, including 29 males and 13 females, with a median age of 46 (15-69) years. In the myocardial tissue of patients with hypertrophic cardiomyopathy with different degrees of fibrosis, miRNAs with significantly different expression were screened and further verified at the cellular level. By regulating the expression of the target miRNAs, the expressions of fibrosis-related proteins and target genes were detected respectively. Finally, the target-binding relationship was verified by dual-luciferase reporter gene detection. ResultsmiR-484 was up-regulated in severely fibrotic myocardial tissue and activated cardiac fibroblasts. After cardiac fibroblasts were activated by TGF-β1, the expression of miR-484 was significantly up-regulated, the expression of fibrosis-related proteins (CollagenⅠ, α-SMA) increased, and the expression of the target gene HIPK1 decreased (P<0.05). After inhibiting the expression of miR-484 by transfection of miR-484 antagomir, the expression of fibrosis-related proteins decreased, while expression of HIPK1 was up-regulated (P<0.05). The detection of dual luciferase reporter gene showed that the luciferase activity of the transfected WT-miRNA-484 mimics group was lower than that of the control group (P<0.05). ConclusionmiR-484 is a pro-fibrotic miRNA that participates in the process of myocardial fibrosis by negatively regulating the expression of HIPK1. It can be used as a regulatory target to provide a therapeutic strategy for myocardial fibrosis.
ObjectiveTo investigate the expressions of microRNA-155 (miR-155) in different phenotypes of activated macrophages. MethodsThe THP-1 cells underwent polarized activation into M1, M2 or tumor-associated macrophages (TAMs), and the phenotypes were confirmed by flow cytometry. The miR-155 expression was determined by qRt-PCR in M1 macrophages, M2 macrophages and TAMs. ResultsThe miR-155 expression significantly decreased in the M2 macrophages (1.83±0.337, P=0.000), TAMs (1.60±0.233, P=0.000) compared with the M1 (6.580±0.637). The phenotype of TAMs was similar to M2. There was no statistically significant difference between TAMs and M2 macrophages in the expression of miR-155 (P=0.546). ConclusionDifferent expressions of miR-155 in macrophages M1-type and M2-type may be associated with the differentiation or their cellular functions. The phenotypic characteristics TAMs may transform to macrophages to M2-type. And they may have the same functions.
ObjectiveTo study the expression levels of miR-339-3p and miR-339-5p in the gastric carcinoma cell lines(SGC-7901, BGC-823, and MKN-45) and gastric surface epithelium(GES-1);detect the relationship between miR-339-3p and miR-339-5p and the gastric carcinoma cell lines in vetrio experiment through the gain of function, and further significance is suggested. MethodsSYBR greenⅠreal time PCR was performed to access the expression of miR-339-3p and miR-339-5p in different cell lines(SGC-7901, BGC-823, MKN-45, and GES-1). The expression levels of miR-339-3p and miR-339-5p were verified by real time PCR experiment again after transfecting miR-339-3p mimics and miR-339-5p mimics. After that, the changes of MKN-45 cells apoptosis and proliferation at 72 h after transfection were detected by flow cytometry and CCK-8 method. ResultsThe expression levels of miR-339-3p and miR-339-5p in gastric carcinoma cell lines(SGC-7901, BGC-823, and MKN-45) were down regulated. Compared with the control group, the apoptosis of MKN-45 cell line was significantly higher(P < 0.05), the ability of proliferation of MKN-45 cell line decreased after transfecting miR-339-3p mimics and miR-339-5p mimics within 72 hours(P < 0.01). ConclusionThe expression levels of miR-339-3p and miR-339-5p significantly decreased in the gastric carcinoma cell lines(SGC-7901, BGC-823, and MKN-45) in contrast with gastric surface epithelium. MiR-339-3p and miR-339-5p may be involved in the apoptosis and proferation of the gastric carcinoma.
Objective To investigate the effect of microRNA-584-5p (miR-584-5p) on the biological behavior (proliferation, migration and invasion) of breast cancer cells and its mechanism. Methods Human normal breast epithelial cells MCF10A and breast cancer cells MDA-MB-231, SK-BR-3 and MCF-7 were selected; take MCF-7 cells in logarithmic growth phase, transfect them with LipofectamineTM 2000 transfection kit, and divide them into seven groups: blank group (untransfected MCF-7 cells), mimic-negative control (mimic-NC) group (transfected mimic-NC), miR-584-5p mimic group (transfected miR-584-5p mimic), pcDNA group [transfected with overexpression of matrix metalloproteinase-14 (MMP-14) pcDNA3.1 plasmid negative control (pcDNA3.1)], MMP-14 group [transfected with overexpression of MMP-14 pcDNA3.1 plasmid (pcDNA3.1-MMP-14)], mimic-NC+MMP-14 group (co-transfected with mimic NC and pcDNA3.1-MMP-14), and miR-584-5p mimic+MMP-14 group (co-transfected with miR-584-5p mimic and pcDNA3.1-MMP-14). The mRNA expression levels of miR-584-5p in MCF10A, MDA-MB-231, SK-BR-3 and MCF-7 cells and the expression levels of miR-584-5p and MMP-14 mRNA of MCF-7 cell in each group were detected by fluorescence quantitative PCR. The protein expressions of MMP-14 of MCF-7 cell in each group were detected by Western blotting. The proliferation, migration and invasion of MCF-7 cell in each group were detected by cell counting kit - 8 (CCK-8), scratch test and Transwell test. The targeting relationship between miR-584-5p and MMP-14 was detected by double luciferase reporter gene assay. Results Compared with the human normal mammary epithelial cells MCF10A, the expression levels of miR-584-5p in breast cancer cells MDA-MB-231, SK-BR-3 and MCF-7 were decreased (P<0.05), and the expression level of miR-584-5p in MCF-7 cells was the lowest. Compared with the blank group and the mimic-NC group, the expression level of miR-584-5p of MCF-7 cells in the miR-584-5p mimic group was increased, and the expression levels of MMP-14 mRNA and protein, proliferation activity, scratch healing rate and invasive cell number were decreased or reduced (P<0.05). Compared with the blank group and the pcDNA group, the expression levels of MMP-14 mRNA and protein, proliferation activity, scratch healing rate and invasive cell number of MCF-7 cells in the MMP-14 group were increased (P<0.05). Compared with the MMP-14 group and the mimic-NC+MMP-14 group, the expression level of miR-584-5p of MCF-7 cells in the miR-584-5p mimic+MMP-14 group was increased, the expression levels of MMP-14 mRNA and protein, proliferation activity, scratch healing rate and invasive cell number were decreased or reduced (P<0.05). The expression levels of MMP-14 mRNA and protein, proliferation activity, scratch healing rate and invasive cell number of MCF-7 cells in the miR-584-5p mimic+MMP-14 group were higher or morer than those in the miR-584-5p mimic group (P<0.05). The results of double luciferase reporter gene test showed that miR-584-5p could targeted action on the MMP-14 promoter region. Conclusions MiR-584-5p can targetable regulate the expression of MMP-14. Overexpression of miR-584-5p inhibits the proliferation, migration and invasion of breast cancer cells by down-regulating MMP-14.
Objective To explore the expression levels and clinical significance of serum long noncoding RNA myocardial infarction associated transcript (lncRNA MIAT) and microRNA-515-5p (miR-515-5p) in elderly patients with chronic obstructive pulmonary disease (COPD) at different periods. Methods From April 2021 to June 2023, 90 elderly patients with acute exacerbation of COPD treated in Huaibei People’s Hospital were selected as a COPD acute exacerbation group, 88 elderly patients with stable COPD as a COPD stable group, and 90 healthy elderly individuals undergoing physical examination as a control group. The white blood cell count (WBC) and serum lncRNA MIAT and miR-515-5p expression levels were detected in all subjects, blood gas analysis and pulmonary function indexes [oxygenation index (PaO2/FiO2), arterial blood carbon dioxide partial pressure (PaCO2), ratio of forced expiratory volume in the first second to forced vital capacity (FEV1/FVC), and FEV1 as a percentage of predicted value (FEV1%pred)] were detected in the patients with COPD. The correlation between serum lncRNA MIAT, miR-515-5p and smoking, WBC, blood gas analysis and pulmonary function indexes were analyzed in the elderly patients with acute exacerbation of COPD. The influencing factors of acute exacerbation of COPD, and the value of serum lncRNA MIAT, miR-515-5p in predicting the occurrence of acute exacerbation of COPD were also analyzed. Results The smoking proportion, WBC, serum lncRNA MIAT expression levels of the control group, the COPD stable group and the COPD acute exacerbation group were increased in turn, serum miR-515-5p expression levels were decreased in turn (P<0.05). Compared with the COPD stable group, PaCO2 was significantly increased in the COPD acute exacerbation group, while PaO2/FiO2, FEV1/FVC and FEV1%pred were significantly decreased (P<0.05); serum lncRNA MIAT in the elderly patients with acute exacerbation of COPD was positively correlated with smoking, WBC, PaCO2 (P<0.05), and negatively correlated with PaO2/FiO2, FEV1/FVC, FEV1%pred, miR-515-5p (P<0.05); serum miR-515-5p was negatively correlated with smoking, WBC, PaCO2 (P<0.05), and positively correlated with PaO2/FiO2, FEV1/FVC, FEV1%pred (P<0.05). Smoking, WBC, PaCO2, and lncRNA MIAT were risk factors affecting the acute exacerbation of COPD patients, PaO2/FiO2, FEV1/FVC, FEV1%pred, miR-515-5p were protective factors affecting the acute exacerbation of elderly COPD patients (P<0.05). The area under the ROC curve (AUC) of serum lncRNA MIAT, miR-515-5p and their combination in predicting acute exacerbation in elderly COPD patients were 0.823, 0.862 and 0.919, respectively, higher than the AUC predicted by serum lncRNA MIAT and miR-515-5p separately (P<0.05). Conclusions Serum lncRNA MIAT expression was high in elderly patients with COPD, and serum miR-515-5p expression was low, and the changes of both were more obvious in patients with acute exacerbation. Both were correlated with blood gas analysis and pulmonary function indexes in patients with acute exacerbation, and have high value in predicting the occurrence of acute exacerbation in elderly patients with COPD.
Objective To summarize the stemness regulation mechanism of microRNA on invasion, metastasis and chemoresistance of gastric cancer stem cells (GCSCs), and to explore the anti-tumor therapy based on miRNA targeting GCSCs. Method The literatures about the research progress of miRNA and GCSCs at home and abroad in recent years were collected and reviewed. Results MiRNA could regulate a series of important cellular processes such as proliferation, apoptosis, differentiation and epithelial-mesenchymal transition of GCSCs by participating in the expression of related target genes, which was associated with poor prognosis and high mortality of gastric cancer patients. Silencing or restoring the expression of candidate miRNA of GCSCs could provide a novel and promising approach for the treatment of gastric cancer. Conclusions GCSCs have an important relationship with the malignant biological behavior of gastric cancer, and studies have confirmed that miRNA play an important regulatory role in GCSCs. Therefore, miRNA can be used as a potential target for the treatment of gastric cancer. By regulating the expression of specific miRNA, it can inhibit tumor invasion and metastasis, and improve the sensitivity of chemotherapy drugs.
ObjectiveTo investigate the specific microRNA (miRNA) in osteogenic and chondrogenic differentiations of C3H10T1/2 cells. MethodsC3H10T1/2 cells were induced to differentiate into osteoblasts and chondrocytes.Specific miRNA more than 2 fold change and 2 average normalized probe signal between C3H10T1/2 and C3H10T1/2-derived osteoblast,and between C3H10T1/2 and C3H10T1/2-derived chondrocytes were screened out by miRNA microarray,and verified by real-time fluorescence quantitative PCR (RT-qPCR). ResultsAlkaline phosphatase expression of osteogenic induced group was significantly higher than that of control group at 7 days after induced (P<0.05).RT-qPCR results showed the expressions of Runx2,serine protease (Sp7),collagen type I,and osteopontin (OPN) genes were significantly increased at 7,14,and 21 days after induced when compared with before induced (P<0.05).Western blot results showed the expressions of Runx2,Sp7,collagen type I,and OPN proteins of osteogenic induced group were significantly higher than those of control group at 21 days after induced (P<0.05).The expressions of SOX9,collagen type Ⅱ,Aggrecan,and Has2 were significantly increased at 5,10,and 15 days after induced when compared with before induced (P<0.05).The expressions of SOX9,collagen type 2,Aggrecan,and Has2 proteins of chondrogenic induced group were significantly higher than those of control group at 15 days after induced (P<0.05).Totally,10 osteogenic and 3 chondrogenic miRNA more than 2 fold change and 2 average normalized probe signal were screened out by miRNA microarray.RT-qPCR results of these specific miRNAs were similar to microarray results except miR-455-3p. ConclusionSpecific miRNAs are screened out by microarray and it is a good foundation for the future study on miRNA functional verification and target gene prediction.