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探讨慢性阻塞性肺疾病(COPD)患者血清中microRNA(miRNA)的差异性表达谱,并通过生物信息学探索其意义。方法 下载GEO数据库开源数据集(GSE70080),分析慢阻肺患者与正常人血清的miRNA差异性表达谱,分析其对慢阻肺的诊断价值,运用miRTarbase、Target Scan、PicTar 、miRDB等软件预测和筛选miRNAs的靶基因,并将得出的上述靶基因功能富集、信号通路及蛋白质互作网络分析。 结果 该数据集中慢阻肺与健康对照组血清差异表达的miRNA共62个(P<0.05) ,其中较对照组上调8个,下调54个,上调miRNA和下调miRNA诊断慢阻肺的受试者曲线下面积分别为0.938和0.969。靶基因预测显示差异性表达miRNA共有15099个靶基因,GO功能分析显示上述靶基因主要涉及Wnt、MAPK、NF-κB等重要生物学过程,KEGG分析主要富集于Wnt、NF κB、MAPK等信号通路。miRNA和mRNA的网络图显示SLC4A8与多个miRNA相关。蛋白质互作网络显示靶基因编码蛋白质间存在复杂的相互作用,ACVR1B、ACVRL1、KRT2、KRT74、KRT82在互作网络中具有核心地位。结论 慢阻肺患者的血清miRNA存在差异性表达,miRNA可能通过调控靶基因参与调控相关的生物功能和通路参与慢阻肺发病机制调控 相似文献
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MicroRNAs (miRNAs) are a class of noncoding RNAs found in organisms as evolutionarily distant as plants and mammals, yet most of the mRNAs they regulate are unknown. Here we show that the ability of an miRNA to translationally repress a target mRNA is largely dictated by the free energy of binding of the first eight nucleotides in the 5' region of the miRNA. However, G:U wobble base-pairing in this region interferes with activity beyond that predicted on the basis of thermodynamic stability. Furthermore, an mRNA can be simultaneously repressed by more than one miRNA species. The level of repression achieved is dependent on both the amount of mRNA and the amount of available miRNA complexes. Thus, predicted miRNA:mRNA interactions must be viewed in the context of other potential interactions and cellular conditions. 相似文献
4.
Kruti B. Shah Steven D. Chernausek Lori D. Garman Nathan P. Pezant Jasmine F. Plows Harmeet K. Kharoud Ellen W. Demerath David A. Fields 《Nutrients》2021,13(4)
Among all the body fluids, breast milk is one of the richest sources of microRNAs (miRNAs). MiRNAs packaged within the milk exosomes are bioavailable to breastfeeding infants. The role of miRNAs in determining infant growth and the impact of maternal overweight/obesity on human milk (HM) miRNAs is poorly understood. The objectives of this study were to examine the impact of maternal overweight/obesity on select miRNAs (miR-148a, miR-30b, miR-29a, miR-29b, miR-let-7a and miR-32) involved in adipogenesis and glucose metabolism and to examine the relationship of these miRNAs with measures of infant body composition in the first 6 months of life. Milk samples were collected from a cohort of 60 mothers (30 normal-weight [NW] and 30 overweight [OW]/obese [OB]) at 1-month and a subset of 48 of these at 3 months of lactation. Relative abundance of miRNA was determined using real-time PCR. The associations between the miRNAs of interest and infant weight and body composition at one, three, and six months were examined after adjusting for infant gestational age, birth weight, and sex. The abundance of miR-148a and miR-30b was lower by 30% and 42%, respectively, in the OW/OB group than in the NW group at 1 month. miR-148a was negatively associated with infant weight, fat mass, and fat free mass, while miR-30b was positively associated with infant weight, percent body fat, and fat mass at 1 month. Maternal obesity is negatively associated with the content of select miRNAs in human milk. An association of specific miRNAs with infant body composition was observed during the first month of life, suggesting a potential role in the infant’s adaptation to enteral nutrition. 相似文献
5.
Ahmet Tektemur Ebru Etem Önalan Nalan Kaya Tektemur Serap Dayan Cinkara Ayten Kılınçlı Çetin İbrahim Tekedereli Tuncay Kuloğlu Gaffari Türk 《Andrologia》2021,53(2):e13954
Male infertility is a global health problem, and the underlying molecular mechanisms are not clearly known. Ion channels and microRNAs (miRNAs), known to function in many vital functions in cells, have been shown to play a significant role in male infertility through changes in their expressions. The study aimed to evaluate the alterations of testicular and/or spermatozoal potassium voltage-gated channel subfamily J member 11 (KCNJ11), Cystic fibrosis transmembrane conductance regulator (CFTR), miR-let-7a and miR-27a expressions in carbamazepine-related male infertility. Here, we showed that carbamazepine reduced sperm motility, increased abnormal sperm morphology, and impaired hormonal balance as well as increased relative testis weight and decreased relative seminal vesicle weight. On the other hand, downregulated KCNJ11 and upregulated miR-let-7a expressions were determined in testis (p < .05). Also, downregulated KCNJ11 and upregulated CFTR and miR-27a expressions were found in spermatozoa (p < .05). Interestingly, altered testicular KCNJ11 and miR-let-7a expressions were correlated with decreased sperm motility and elevated sperm tail defect. Besides, spermatozoal CFTR and miR-27a expressions positively correlated with sperm tail defects. The results indicated a significant relationship between ion channel and/or miRNA expression alterations and impaired sperm parameters due to carbamazepine usage. 相似文献
6.
Takuto Chiba Dbora M. Cerqueira Yao Li Andrew J. Bodnar Elina Mukherjee Katherine Pfister Yu Leng Phua Kai Shaikh Brandon T. Sanders Shelby L. Hemker Patrick J. Pagano Yijen L. Wu Jacqueline Ho Sunder Sims-Lucas 《Journal of the American Society of Nephrology : JASN》2021,32(3):553
BackgroundDamage to the renal microvasculature is a hallmark of renal ischemia-reperfusion injury (IRI)–mediated AKI. The miR-17∼92 miRNA cluster (encoding miR-17, -18a, -19a, -20a, -19b-1, and -92a-1) regulates angiogenesis in multiple settings, but no definitive role in renal endothelium during AKI pathogenesis has been established.MethodsAntibodies bound to magnetic beads were utilized to selectively enrich for renal endothelial cells from mice. Endothelial-specific miR-17∼92 knockout (miR-17∼92endo−/−) mice were generated and given renal IRI. Mice were monitored for the development of AKI using serum chemistries and histology and for renal blood flow using magnetic resonance imaging (MRI) and laser Doppler imaging. Mice were treated with miRNA mimics during renal IRI, and therapeutic efficacies were evaluated.ResultsmiR-17, -18a, -20a, -19b, and pri–miR-17∼92 are dynamically regulated in renal endothelial cells after renal IRI. miR-17∼92endo−/− exacerbates renal IRI in male and female mice. Specifically, miR-17∼92endo−/− promotes renal tubular injury, reduces renal blood flow, promotes microvascular rarefaction, increases renal oxidative stress, and promotes macrophage infiltration to injured kidneys. The potent antiangiogenic factor thrombospondin 1 (TSP1) is highly expressed in renal endothelium in miR-17∼92endo−/− after renal IRI and is a target of miR-18a and miR-19a/b. miR-17∼92 is critical in the angiogenic response after renal IRI, which treatment with miR-18a and miR-19b mimics can mitigate.ConclusionsThese data suggest that endothelial-derived miR-17∼92 stimulates a reparative response in damaged renal vasculature during renal IRI by regulating angiogenic pathways. 相似文献
7.
微RNA在肿瘤研究中的意义 总被引:1,自引:0,他引:1
微RNA(microRNA;miRNA),又名小分子RNA,是序列特异转录后抑制基因表达的调节因子,是一种长约19~25nt广泛存在于真核细胞胞质内的单链小分子RNA,是一组不编码蛋白质的短序列RNA,它本身不具有开放阅读框(ORF);成熟的miRNA 5′端有一个磷酸基团,3′端为羟基.miRNA参与生命过程中一系列的重要进程,包括个体发育、造血生成、器官形成、细胞凋亡、细胞增殖与分化、脂肪代谢,甚至肿瘤发生.为更全面地认识miRNA,特别是miRNA在肿瘤诊治中的意义,本文将从以下几个方面对miRNA的研究做一介绍. 相似文献
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Plasma microRNA‐based signatures to predict 3‐year postoperative recurrence risk for stage II and III gastric cancer
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10.
目的:探讨土龙祛疣洗剂对尖锐湿疣(CA)皮损标本中micro RNA分子表达谱的影响。方法:以39例CA患者为观察组,使用土龙祛疣洗剂熏洗治疗,6周后观察疗效。以同期自本院外科就诊的10例行包皮环切患者为对照组,取其正常包皮组织。采用q RT-PCR检测2组5个炎症相关micro RNA(mi R-21、mi R-203、mi R-125b、mi R-146a和mi R-155)的表达情况。结果:39例CA患者治疗6周后27例皮损消退明显,症状减轻,总有效率为69.2%;观察组mi R-203与正常对照组相比呈现低表达,土龙祛疣洗剂治疗后呈现明显上调,差异有统计学意义(P0.01);mi R-21治疗后表达量与治疗前相比则下调明显(P0.05);而mi R-155、mi R-125b、mi R-146a分子在治疗前后无明显变化。结论:土龙祛疣洗剂治疗尖锐湿疣疗效肯定,可能通过下调mi R-21和上调mi R-203分子来发挥抗病毒的治疗作用。 相似文献