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1.
BackgroundEmerging evidence reveals the importance of long non-coding RNAs (lncRNAs) in the development and progression of keloid formation. However, the roles and molecular mechanism of lncRNA LINC01116 in the progression of keloid formation remain largely unknown.MethodsThe expression levels of LINC01116, microRNA-203 (miR-203) and SMAD family member 5 (SMAD5) were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Cell proliferation, migration and invasion were detected by Cell counting Kit-8 (CCK-8) assay and transwell assay. Flow cytometry and western blot assay were used to examine cell apoptosis and extracellular matrix (ECM) production. The interaction between miR-203 and LINC01116 or SMAD5 was predicted by bioinformatics analysis and verified by dual-luciferase reporter and RNA Immunoprecipitation (RIP) and RNA pull-down assays.ResultsLINC01116 and SMAD5 were upregulated while miR-203 was downregulated in keloid tissues and keloid fibroblasts. LINC01116 knockdown suppressed the proliferation, migration, invasion, and ECM production but induced apoptosis in keloid fibroblasts through enhancing miR-203 and inhibiting SMAD5. Moreover, SMAD5 was identified as a direct target of miR-203 and miR-203 could directly bind to LINC01116. Besides, LINC01116 regulated SMAD5 expression by targeting miR-203.ConclusionDownregulation of LINC01116 inhibited the progression of keloid formation by regulating miR-203/SMAD5 axis, which might provide a novel target for keloid therapy.  相似文献   
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The effects of norepinephrine receptor blockade on the deficits of escape behavior induced by haloperidol and by inescapable shock were evaluated. Phenoxybenzamine, the -norepinephrine receptor blocker, was found to enhance escape behavior and to eliminate the disruptive effects of both inescapable shock and haloperidol. In contrast, the -norepinephrine receptor antagonist, propranolol, was without effect on behavior under any of these conditions, while the dopamine--hydroxylase inhibitor, FLA-63, disrupted performance. Like phenoxybenzamine, the norepinephrine receptor stimulant, clonidine, was found to eliminate the behavioral disruption produced by haloperidol. These somewhat paradoxical findings were discussed in terms of the contribution of DA-NE interactions in determining behavioral change in aversive paradigms.  相似文献   
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Ethnopharmacological relevance

The bark of Tecomella undulata is primarily used in the treatment of syphilis, painful swellings and cancer by traditional healers. Also, it is claimed to be useful in treating urinary discharges, enlargement of spleen, leucorrhoea, leukoderma, tumors, liver disorders, gonorrhea, gout and promotes wound healing in Indian traditional system of medicine.

Aim

To establish a scientific validation for the antitumor effects of Tecomella undulata bark and explore the mechanistic pathway in chronic myeloid leukemia cell line, K562. The study was further extended to standardize the extract using quercetin as biomarker.

Methods

Induction of apoptosis by chloroform extract of Tecomella undulata bark (CTUB) was determined by MTT, Annexin V and caspase activation assays. The cell cycle analysis was done by flow cytometer and nuclear staining by DAPI. The standardization of the extract was performed through reverse phase-HPLC method under PDA detection.

Result

Results clearly showed the induction of apoptosis by CTUB in K562 cells. The effect was found to be dose dependent, having IC50 of 30 μg/ml with activation of FAS, FADD, caspase 8, caspase 3/7 and fragmentation of DNA. The bioactive CTUB was determined to possess 0.03% (w/w) of quercetin.

Conclusion

The investigation clearly demonstrated the potential antitumor effect of CTUB, thereby validating the traditional claim. Quercetin, known to have anticancer activity is being reported and quantified for the first time from the bark of Tecomella undulata.  相似文献   
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Abstinence from prolonged psychostimulant use prompts stimulant withdrawal syndrome. Molecular adaptations within the dorsal striatum have been considered the main hallmark of stimulant abstinence. Here we explored striatal miRNA–target interaction and its impact on circulating miRNA marker as well as behavioral dysfunctions in methamphetamine (MA) abstinence. We conducted miRNA sequencing and profiling in the nonhuman primate model of MA abstinence, followed by miRNA qPCR, LC–MS/MS proteomics, immunoassays, and behavior tests in mice. In nonhuman primates, MA abstinence triggered a lasting upregulation of miR-137 in the dorsal striatum but a simultaneous downregulation of circulating miR-137. In mice, aberrant increase in striatal miR-137-dependent inhibition of SYNCRIP essentially mediated the MA abstinence-induced reduction of circulating miR-137. Pathway modeling through experimental deduction illustrated that the MA abstinence-mediated downregulation of circulating miR-137 was caused by reduction of SYNCRIP-dependent miRNA sorting into the exosomes in the dorsal striatum. Furthermore, diminished SYNCRIP in the dorsal striatum was necessary for MA abstinence-induced behavioral bias towards egocentric spatial learning. Taken together, our data revealed circulating miR-137 as a potential blood-based marker that could reflect MA abstinence-dependent changes in striatal miR-137/SYNCRIP axis, and striatal SYNCRIP as a potential therapeutic target for striatum-associated cognitive dysfunction by MA withdrawal syndrome.  相似文献   
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王昌兰  高志红  常爱玲  王宝利 《天津医药》2015,43(12):1353-1355
目的探讨miR-320-3p 对脂肪细胞分化的影响。方法分离并培养小鼠骨髓间充质干细胞(MSCs),并对其进行脂肪细胞诱导分化3 d,用qRT-PCR 检测miR-320-3p 在成脂分化过程中的表达水平。在骨髓基质细胞系 ST2 中转染miR-320-3p,对其进行成脂方向诱导分化,用油红O 染色和qRT-PCR 检测miR-320-3p 对ST2 成脂分化的影响。结果MSCs 向脂肪细胞分化过程中miR-320-3p 表达增加(P < 0.01);与转染阴性对照NC mimics 相比,ST2 细胞转染miR-320-3p mimics 后油红O 染色显示脂肪细胞明显增多,脂肪细胞特异性转录因子过氧化物酶体增殖物激活受体γ(PPARγ)、CCAAT 增强子结合蛋白α(C/EBPα)和脂肪细胞脂肪酸结合蛋白4(FABP4)基因表达显著升高,差异有统计学意义(P < 0.05)。结论miR-320-3p 可促进ST2 向脂肪细胞分化。  相似文献   
8.
目的 探讨丹参酮ⅡA对于心力衰竭大鼠心肌凋亡的影响及调控miR-133水平的机制。方法 采用胸主动脉缩窄法(TAC)建立心力衰竭大鼠模型,并给予连续12周的丹参酮ⅡA磺酸钠注射液治疗,同时部分心力衰竭大鼠皮下植入渗透泵持续泵入miR-133抑制剂antagomirs,以观察其抑制miR-133的水平。分析12周后的血流动力学情况、心肌细胞的凋亡情况(采用TUENL法)、心肌促凋亡基因(Bax和Caspase-3)以及抑制凋亡基因(Bcl-2)的表达情况(采用Western blot及RT-PCR法)。结果 与假手术比较,TAC处理可导致心功能恶化(除平均动脉压外),心肌细胞的凋亡水平升高,Bax和Caspase-3蛋白和mRNA水平均上升,miR-133及Bcl-2蛋白和mRNA水平均下调;给予丹参酮ⅡA处理的TAC大鼠,除了心功能中的心率没有改善外,其余指标均有显著改善,且差异有统计学意义;皮下连续泵入antagomirs能够部分消除丹参酮ⅡA的作用。结论 丹参酮ⅡA可降低心力衰竭大鼠的心肌凋亡水平,可能的机制是上调miR-133水平实现的。  相似文献   
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孟娜  顾悦  孔瑞芹  王瑛璞 《广东医学》2021,42(5):545-549
目的 探讨miR-211对高糖诱导下晶状体上皮细胞氧化应激反应的调控作用及其可能存在的作用机制.方法 将HLEC-B3细胞在含不同浓度(0、10、20、40 mmol/L)葡萄糖的培养基中培养48 h,RT-PCR检测细胞miR-211表达,Western blot检测细胞SIRT1蛋白表达,试剂盒检测总抗氧化能力(T...  相似文献   
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