| Objective: By using miRNA chips,real time PCR(qPCR)and other techniques,this study was aimed to detect the expression profiles and analyze the differences of microRNA(mi RNA)in the plasma of COPD patients and normal subjects from Li and Han ethnic group of Hainan province.Based on the comparative study of miRNA expression in peripheral blood of Li and Han ethnic,then combined with bioinformatics analysis and cytology research,we found new clues for the mechanism of COPD.Methods: A total of 216 samples were collected from Hainan Li and Han nationality,we finally screened 32 samples for the corresponding grouping.Based on the previous research,Differentially expressed mi RNA was preliminary detected by using miRNA chip;And 72 cases were screened by real-time fluorescence quantitative PCR(qRT-PCR)from samples,The differentially expressed 13 miRNAs in peripheral blood were measured and compared.Finally,four differentially expressed miRNAs were selected and transfected into human lung fibroblasts to further validate the effects of proliferation,apoptosis,and the regulation of target genes.Results:(1)miRNA chip scanning and analysis' results showed that 18 miRNAs were differentially expressed in peripheral blood,we confirmed that13 miRNAs may play a role in the occurrence of COPD by statistical analysis;(2)Further qRT-PCR was used to verify the extended sample between the 13 miRNAs in a single individual,we found 7 differentiallyexpressed miRNAs in COPD patients of Li population and 1 differentially expressed miRNA in COPD patients of Han population among the 72 clinical subjects,reflected there may be differences between the two peoples;(3)Smokers and non-smokers were stratified and no differentially expressed miRNAs were found(smokers vs non-smokers in case and control groups);(4)In the univariate analysis of the influence of environmental factors on the expression of miRNA in peripheral blood of COPD patients,it was found that BMI,age and smoking age could be the main risk factors for the differential expression of circulating miRNA in Li and Han nationality with COPD;(5)We chose 4 differentially expressed miRNAs(including hsa-mi R-146b-5p,hsa-mi R-141-3p,hsa-miR-186-5p and hsa-miR-196b-5p)to construct lentiviral vector,and transfected them in human lung fibroblasts to further validate.We discovered mir-146 b and mir-141 can promote cell proliferation and inhibit apoptosis;On the contrary,mir-186 can promote apoptosis and inhibit cell proliferation.We confirmed mir-186 can inhibit human lung fibroblasts' proliferation and promote their apoptosis by further study.We also figured out mir-186 can combine with HIF1 A 3'UTR region and inhibit its protein expression.Through bioinformatics analysis,mir-186 can also combine with HIF1 A 3'UTR,It was demonstrated by double luciferase that mir-186 may inhibit human lung fibroblasts' proliferation and promote its apoptosis by HIF1 A,and then influenced the occurrence and development of COPD.Coclusions:(1)miRNAs' differential expression existed in peripheral blood Li and Han inter and instraspcific ethnic group in Hainan province;(2)Hainan Li and Han patients with normal and COPD peripheral blood miRNA expression differences,suggesting that miRNAs may have certainsignificance in the pathogenesis of COPD;(3)Multiple miRNAs may play an important role in the pathogenesis of COPD by affecting the proliferation and apoptosis of lung fibroblasts,which may be involved in airway remodeling;(4)Mir-186 can inhibit the proliferation of human lung fibroblasts and promote its apoptosis,may be through the regulation of downstream HIF1 A expression to achieve and affect the downstream signal signal pathways,and thus participate in the development of COPD;(5)Further study of mir-186 may provide new markers for the diagnosis of COPD and provide a new target for its treatment and a new basis for the evaluation of its prognosis;(6)The interaction between abnormal expression of miRNA and environmental factors has some influence on the pathogenesis of COPD,but it needs further study. |
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