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1.
MiR-204 is expressed in vascular smooth muscle cells (VSMC). However, its role in VSMC contraction is not known. We determined if miR-204 controls VSMC contractility and blood pressure through regulation of sarcoplasmic reticulum (SR) calcium (Ca2+) release. Systolic blood pressure (SBP) and vasoreactivity to VSMC contractile agonists (phenylephrine (PE), thromboxane analogue (U46619), endothelin-1 (ET-1), angiotensin-II (Ang II) and norepinephrine (NE) were compared in aortas and mesenteric resistance arteries (MRA) from miR-204−/− mice and wildtype mice (WT). There was no difference in basal systolic blood pressure (SBP) between the two genotypes; however, hypertensive response to Ang II was significantly greater in miR-204−/− mice compared to WT mice. Aortas and MRA of miR-204−/− mice had heightened contractility to all VSMC agonists. In silico algorithms predicted the type 1 Inositol 1, 4, 5-trisphosphate receptor (IP3R1) as a target of miR-204. Aortas and MRA of miR-204−/− mice had higher expression of IP3R1 compared to WT mice. Difference in agonist-induced vasoconstriction between miR-204−/− and WT mice was abolished with pharmacologic inhibition of IP3R1. Furthermore, Ang II-induced aortic IP3R1 was greater in miR-204−/− mice compared to WT mice. In addition, difference in aortic vasoconstriction to VSMC agonists between miR-204−/− and WT mice persisted after Ang II infusion. Inhibition of miR-204 in VSMC in vitro increased IP3R1, and boosted SR Ca2+ release in response to PE, while overexpression of miR-204 downregulated IP3R1. Finally, a sequence-specific nucleotide blocker that targets the miR-204-IP3R1 interaction rescued miR-204-induced downregulation of IP3R1. We conclude that miR-204 controls VSMC contractility and blood pressure through IP3R1-dependent regulation of SR calcium release.  相似文献   
2.
Previous studies have shown that microRNA-206 (miR-206) exhibits anti-tumour properties in various tumours. Nevertheless, diagnostic significance of miR-206 in oral cancer is still poorly known. Our research was carried out to explore the performance of miR-206 in the diagnosis of oral cancer. Quantitative real-time polymerase chain reaction (qRT-PCR) method was adopted to measure the level of miR-206 in serum specimens from oral cancer cases and control individuals. Chi-square test was performed to analyse the correlation between miR-206 level and clinicopathological parameters of the cases. Receiver operating characteristic (ROC) curve was constituted to assess diagnostic accuracy of miR-206 in oral cancer. Serum miR-206 level in oral cancer patients was significantly lower than that in control individuals (P < .001). miR-206 expression was obviously related to T classification (P = .033), TNM stage (P = .008) and lymph node metastasis (P = .028). The area under the curve (AUC) of the ROC curve was 0.846 (95% CI = 0.797-0.896, P < .001) with a specificity of 72.7% and a sensitivity of 81.2%. It revealed that miR-206 might be a non-invasive indicator in differentiating oral cancer cases from control individuals. Down-regulation of miR-206 is related to the development of oral cancer. Serum miR-206 might be an effective indicator for early detection of oral cancer.  相似文献   
3.
A programme of research was initiated to provide information on the efficacy of the antifouling agents Irgarol 1051™ and Sea-Nine 211™ to zygotes of the fucoid alga Fucus serratus Linnaeus. The development of methodologies that incorporated the use of image capture and analysis, which minimised the problems of subjectivity and bias that can be typical, are also described. The generation of macro-instructions allowed rapid generation and interpretation of accurate quantitative data. Emphasis was placed on the use of methodologies that did not rely on the subjective determination of spore germination. Consequently, affects due to the biocides were determined that, otherwise, would not have been realised through normal analytical routines.Zygotes were exposed, in static non-renewal systems, for 3 days, to a range of concentrations of biocide dissolved in seawater. Data for seven zygote parameters were recorded daily and values of percentage germination were calculated. From these data, NOEC values of 8 μg l−1 were calculated for both Sea-Nine 211 and Irgarol 1051. An EC50 of 19.4 μg l−1 was also determined for Sea-Nine 211. It is, therefore, suggested that F. serratus zygote germination and early development is unaffected by published environmental concentrations of these biocides. Additionally, it has been demonstrated that the image capture and analysis methodologies developed provide an invaluable tool for use in future bioassays.  相似文献   
4.

A simple method to measure the degradation of antifouling biocides is described which measures the loss of biocidal activity from seawater by bioassay. The bioassay employs either the ship‐fouling diatom Amphora or the brine shrimp Anemia. Loss of bioaclivity from sterile seawater indicates abiotic degradation whilst loss of bioactivity from natural seawater indicates biodegradation. Results are presented for three biocides, viz. the trihalomethylthio compound, N‐dichlorofluoromethylthio‐N’,N'‐dimethyl‐N‐phenyl‐sulphamide (Preventol A4S), di‐n‐octylamine, and the isothiazolone compound 4,5‐dichloro‐2‐n‐octyl‐4‐isothiazolin‐3‐one (Sea‐Nine 211).  相似文献   
5.
Tumor suppressor long noncoding RNA maternally expressed gene 3 (lncRNA MEG3) exists in various cancers. Nonetheless, the functions of lncRNA MEG3 in choriocarcinoma (CC) are still not well studied. We explored the effects of lncRNA MEG3 on human CC JEG-3 and BeWo cells. lncRNA MEG3 was overexpressed, and the effects of lncRNA MEG3 on cell viability, proliferation, apoptosis, migration, and invasion were assessed by the cell counting kit-8 assay, western blot analysis, flow cytometry (plus western blot analysis), and transwell assay (plus western blot analysis), respectively. Then, the expression level of miR-211 was detected by real-time quantitative polymerase chain reaction. After that, the effects of dysregulated microRNA-211 (miR-211) with overexpressing lncRNA MEG3 on JEG-3 cells and BeWo cells were testified. Western blot analysis was used to study the involvements of the signaling pathways in the lncRNA MEG3-associated modulation. We found that lncRNA MEG3 upregulation reduced cell viability, inhibited proliferation, migration and invasion, and promoted apoptosis. Expression of miR-211 was upregulated after lncRNA MEG3 overexpression. Effects of lncRNA MEG3 overexpression were augmented by miR-211 overexpression, while they were declined by miR-211 silencing. Phosphorylated levels of PI3K, AKT, and AMP-activated protein kinase (AMPK) were decreased by lncRNA MEG3 overexpression via regulation of miR-211. To sum up, lncRNA MEG3 could repress proliferation, migration and invasion, and promote apoptosis of JEG-3 and BeWo cells through upregulating miR-211. The PI3K/AKT and AMPK pathways were inhibited by lncRNA MEG3 overexpression via regulation of miR-211.  相似文献   
6.
Diabetic retinopathy (DR) remains the leading cause of blindness in adults with diabetes mellitus. Numerous microRNAs (miRNAs) have been identified to modulate the pathogenesis of DR. The main purpose of this study was to evaluate the potential roles of miR-455-5p in high glucose (HG)-treated retinal pigment epithelial (RPE) cells and underlying mechanisms. Our present investigation discovered that the expression of miR-455-5p was apparently downregulated in ARPE-19 cells stimulated with HG. In addition, forced expression of miR-455-5p markedly enhanced cell viability and restrained HG-induced apoptosis accompanied by decreased BCL2-associated X protein (Bax)/B-cell leukemia/lymphoma 2 (Bcl-2) ratio and expression of apoptotic marker cleaved caspase-3 during HG challenged. Subsequently, augmentation of miR-455-5p remarkably alleviated HG-triggered oxidative stress injury as reflected by decreased the production of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) content as well as NADPH oxidase 4 expression, concomitant with enhanced the activities of superoxide dismutase, catalase, and GPX stimulated with HG. Furthermore, enforced expression of miR-455-5p effectively ameliorated HG-stimulated inflammatory response as exemplified by repressing the secretion of inflammatory cytokines interleukin 1β (IL-1β), IL-6, and tumour necrosis factor-α in ARPE-19 cells challenged by HG. Most importantly, we successfully identified suppressor of cytokine signaling 3 (SOCS3) as a direct target gene of miR-455-5p, and miR-455-5p negatively regulated the expression of SOCS3. Mechanistically, restoration of SOCS3 abrogated the beneficial effects of miR-455-5p on apoptosis, accumulation of ROS, and inflammatory factors production in response to HG. Taken together, these findings demonstrated that miR-455-5p relieved HG-induced damage through repressing apoptosis, oxidant stress, and inflammatory response by targeting SOCS3. The study gives evidence that miR-455-5p may serve as a new potential therapeutic agent for DR treatment.  相似文献   
7.
摘要 目的:我们前期研究发现有氧运动促进内皮细胞等分泌miR-342-5p,miR-342-5p通过外泌体富集至心肌细胞后发挥心脏保护作用。本研究的主要目的是明确内皮来源的miR-342-5p在心血管功能调控中的作用。方法:我们构建了内皮特异性miR-342-5p敲除小鼠,通过心脏超声检测和血管收缩舒张功能检测观察了该小鼠心血管功能的变化;培养血管内皮细胞,通过对细胞存活率检测、相关蛋白的表达检测等方法对miR-342-5p发挥心血管保护作用的机制进行探究。结果:内皮miR-342-5p敲除致小鼠运动能力降低、心脏收缩功能不变,但舒张功能紊乱。且内皮miR-342-5p敲除致小鼠血管口径变小、微血管密度降低和血管内皮功能紊乱。内皮miR-342-5p敲除致小鼠心血管功能紊乱的机制与其引起的内皮细胞损伤有关。敲低miR-342-5p致内皮细胞中caspase 9水平增加,引起内皮细胞活性降低和凋亡增加。结论:这些结果进一步证实了内皮细胞来源的miR-342-5p在心血管功能中的重要作用,提示miR-342-5p在防治心血管疾病中的潜在应用。  相似文献   
8.
摘要 目的:通过动物实验,具体探讨微小RNA(miR-10a)通过含F-框WD重复域蛋白7(FBXW7)-E盒锌指结合蛋白2(ZEB2)轴调控非小细胞肺癌的肿瘤化疗耐药作用。方法:非小细胞肺癌模型小鼠(n=42)随机平分为三组-模型组、miR-10a组与环磷酰胺组,模型组给予生理盐水0.2 mL腹腔注射,环磷酰胺组给予环磷酰胺20 mg/kg腹腔注射,miR-10a组给hsa-miR-10a mimics 15 mg/kg 联合环磷酰胺20 mg/kg腹腔注射,1次/d,持续给药14 d。结果:miR-10a组与环磷酰胺组治疗第7 d与第14 d的肿瘤体积低于模型组,miR-10a组低于环磷酰胺组(P<0.05)。miR-10a组与环磷酰胺组治疗第14 d与第28 d的瘤体质量低于模型组,抑瘤率高于模型组,miR-10a组与环磷酰胺组对比差异也有统计学意义(P<0.05)。miR-10a组与环磷酰胺组治疗第14 d与第28 d的肿瘤细胞凋亡指数高于模型组,miR-10a组高于环磷酰胺组(P<0.05)。miR-10a组与环磷酰胺组治疗第14 d与第28 d的血清FBXW7、ZEB2含量低于模型组,miR-10a组低于环磷酰胺组(P<0.05)。miR-10a组与环磷酰胺组治疗第14 d与第28 d的FBXW7、ZEB2 mRNA与蛋白相对表达水平低于模型组,miR-10a组低于环磷酰胺组(P<0.05)。结论:过表达miR-10a能抑制非小细胞肺癌小鼠的FBXW7-ZEB2轴的激活,抑制血清FBXW7、ZEB2的表达,从而促进肿瘤细胞凋亡,改善肿瘤化疗耐药性,促进缩小肿瘤体积。  相似文献   
9.
MicroRNA(miRNA)是一类包含21-25个核苷酸的单链非编码小RNA.研究表明,miR-210可直接抑制线粒体内铁硫蛋白(Fe-S)的支架蛋白ISCUl/2的表达从而抑制线粒体代谢;miR-210对DNA损伤修复基因-RAD家族有抑制作用,减弱了DNA修复能力;miR-210可以通过调节E2F3、纤维母细胞生长因子受体1(FGFRL1)、同源域基因A1(HOXA1)等阻止细胞增殖,调控细胞周期;缺氧刺激可上调miR-210表达,这对促进血管再生有重要作用.miR-210的表达受缺氧诱导,调控缺氧反应相关基因的表达,提示miR-210有可能成为诊治包括缺血性损伤、肿瘤在内等多种疾病的新靶点.  相似文献   
10.
Colorectal cancer (CRC), the third most common cancer worldwide, also has the highest rate of cancer-related morbidity and mortality. WNT signaling is initiated by binding of WNT to various receptors, including frizzleds (FZDs), and plays a critical role in CRC and other tumor development by regulating proliferation, differentiation, migration, apoptosis, and polarity. Among the members of the FZD family, FZD6 is broadly expressed in various tissues, and its overexpression has been reported in several cancers, suggesting an important role in cancer development. In this study, we investigated the expression of FZD6 in patients with CRC and found it to be increased in tumors, as compared to paired adjacent non-tumor tissues. Additionally, we found that FZD6 expression was negatively regulated by miR199a5p in CRC cells. These results suggest that overexpression of FZD6, mediated by reduced expression of miR-199a-5p, may play an important role in the development of CRC. [BMB Reports 2015; 48(6): 360-366]  相似文献   
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