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PurposeAs the population ages, the incidence of clinical dementia has been rising around the world. It has been reported that microRNAs act as key diagnostic biomarkers and targets for various neurological conditions, including dementia. MiR-322-5p has been revealed to play an important role in multiple diseases. In this study, we aimed to investigate the role and regulatory mechanism of miR-322-5p in vascular dementia.Materials and MethodsIn this study, neonatal rat neurons (NRNs) were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to induce cell injury. The animals were subjected to permanent bilateral occlusion of the carotid arteries (2-vessel occlusion, 2VO) to induce the model of chronic brain hypoperfusion.ResultsMiR-322-5p expression was significantly downregulated in the neurons exposed to OGD/R and the hippocampi of 2VO rats. Overexpression of miR-322-5p ameliorated cell apoptosis and the inflammatory response in vitro. In a mechanistic study, miR-322-5p was confirmed to directly target and negatively regulate tetraspanin 5 (TSPAN5) in cultured NRNs. Moreover, overexpression of TSPAN5 could counteract the effects of miR-322-5p overexpression on cell apoptosis and the inflammatory response in OGD/R-treated neurons. More importantly, miR-322-5p improved cognitive ability and inhibited inflammatory production in 2VO rats.ConclusionOverall, the results suggest that miR-322-5p alleviates vascular dementia development by targeting TSPAN5. This discovery may provide a potential therapeutic target for dementia. 相似文献
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目的探讨血浆miR-106b-5p在原发免疫性血小板减少症(primary immune thrombocytopenia,ITP)中的表达及其与辅助性T细胞17(T helper cells 17,Th17)、调节性T细胞(T regulatory cell,Treg)、Th17/Treg的相关性。方法选取79例ITP患儿(ITP组)和40例健康儿童(对照组)为研究对象。79例ITP患儿根据治疗效果分为完全有效组(40例)、有效组(18例)、无效组(21例)。采用实时荧光定量PCR技术检测miR-106b-5p表达水平,流式细胞技术检测Th17和Treg,计算Th17/Treg,分析血浆miR-106b-5p表达水平与Th17、Treg及Th17/Treg的相关性。结果ITP组miR-106b-5p、Th17及Th17/Treg水平高于对照组(P<0.05),Treg水平低于对照组(P<0.05)。ITP组患儿治疗后miR-106b-5p、Th17、Th17/Treg水平低于治疗前(P<0.05),Treg水平高于治疗前(P<0.05)。完全有效组miR-106b-5p、Th17、Th17/Treg水平低于有效组和无效组(P<0.05),Treg水平高于有效组和无效组(P<0.05)。相关分析显示,ITP患儿血浆miR-106b-5p表达水平与Th17、Th17/Treg均呈正相关(分别r=0.730、0.816,均P<0.001),与Treg呈负相关(r=-0.774,P<0.001)。结论ITP患儿存在miR-106b-5p高表达和Th17/Treg比例失衡,在ITP患儿治疗过程中检测miR-106b-5p、Th17、Treg及Th17/Treg水平,对ITP患儿的疗效判断具有较好的指导作用。 相似文献
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Siwen Yang Yunkun Zhang Chunmei Guo Rui Liu Maroua Elkharti Zhenhua Ge Qinlong Liu Shuqing Liu Ming-Zhong Sun 《American journal of cancer research》2022,12(6):2492
A better understanding of tumor metastasis is urgently required for the treatment and prognosis of hepatocarcinoma patients. Current work contributes a novel ceRNA feedback regulation pathway composed of epiregulin (EREG), microRNA-330-3p (miR-330-3p) and long non-coding RNA 021545 (lncRNA021545) in regulating hepatocarcinoma malignancy via epithelial-mesenchymal transition (EMT) process. Closely correlated, the deficiencies of EREG and lncRNA021545 and the overexpression of miR-330-3p were involved in the clinical progression of hepatocarcinoma. In vitro results showed that 1) lncRNA021545 downregulation promoted, 2) miR-330-3p dysexpression positively correlated, and 3) EREG dysexpression reversely correlated with the migratory and invasive properties of hepatocarcinoma HCCLM3 and Huh7 cell lines. By directly binding to EREG and lncRNA021545, miR-330-3p expression change reversely correlated with their expressions in HCCLM3 and Huh7 cells, which was also confirmed in primary tumors from HCCLM3-xenograft mice in responding to miR-330-3p change. LncRNA021545 and EREG positively regulated each other, and lncRNA021545 negatively regulated miR-330-3p, while, EREG dysregulation unchanged miR-330-3p expression in hepatocarcinoma cells. Furthermore, systemic in vitro cellular characterizations showed that the malfunctions of the three molecules mediated the invasiveness of hepatocarcinoma cells via EMT process through affecting the expressions of E-cadherin, N-cadherin, vimentin, snail and slug, which was further confirmed by in vivo miR-330-3p promotion on the tumorigenicity and metastasis of HCCLM3 bearing nude mice and by in vitro miR-330-3p promotion on the migration and invasion of hepatocarcinoma cells to be antagonized by EREG overexpression through acting on EMT process. Our work indicates, that by forming a circuit signaling feedback pathway, the homeostatic expressions of lncRNA021545, miR-330-3p and EREG are important in liver health. Its collapse resulted from the downregulations of lncRNA021545 and EREG together with miR-330-3p overexpression promote hepatocarcinoma progression by enhancing the invasiveness of tumor cells through EMT activation. These discoveries suggest that miR-330-3p/lncRNA021545/EREG axis plays a critical role in hepatocarcinoma progression and as a candidate for its treatment. 相似文献
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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
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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