OBJECTIVE Although it is generally believed that nicotine accounts for the beneficial effect of smoking on ulcerative colitis,the underlying mechanisms remain not well-understood.Our previous finding that nicotine inh...OBJECTIVE Although it is generally believed that nicotine accounts for the beneficial effect of smoking on ulcerative colitis,the underlying mechanisms remain not well-understood.Our previous finding that nicotine inhibits inflammatory responses through inducing miRNA-124 prompted us to ask whether the miRNA is involved in the protective action of nicotine on UC.METHODS Mi R-124 expression in colon tissues and cells was determined by q-PCR and in situ hybridization.The effect of miR-124 on protective role of nicotine in ulcerative colitis was evaluated in DSS-treated mice and IL-6-treated Caco-2 colon epithelial cells.Expression of p-STAT3/STAT3 was detected by immunohistochemistry and Western blot analysis.RESULTS miR-124 expression is upregulated in colon tissues from patients and DSS-induced colitis.Nicotine treatment further elevated miR-124 level in colon tissues of the mice,in infiltrated lymphocytes and epithelial cells,and augmented miR-124 expression in lymphocytes isolated from human ulcerative colon tissues.Administration of nicotine also reduced weight loss,improved DAI and decreased HE score in DSS-induced colitis.Moreover,knockdown of miR-124 in vivo significantly diminished the beneficial effect of nicotine,and in vitro on IL-6-treated Caco-2 colon epithelial cells.Further analysis indicated that nicotine inhibited STAT3 activation in vivo and in IL-6-treated Caco-2 colon epithelial cells and Jurkat human T lymphocytes,in whichmiR-124 knockdown led to increased activation of STAT3.CONCLUSION These data indicated that nicotine exerts its protective action in UC through inducing miR-124 and its effect on STAT3,suggesting that the miR-124/STAT3 system is a potential target for the therapeutic intervention of UC.展开更多
The vagus nerve can control inflammatory response through a ＇ cholinergic anti-inflammatory pathway＇, which is mediated by the α7-nicotinic acetylcholine receptor （α7nAChR） on macrophages. However, the intracel-...The vagus nerve can control inflammatory response through a ＇ cholinergic anti-inflammatory pathway＇, which is mediated by the α7-nicotinic acetylcholine receptor （α7nAChR） on macrophages. However, the intracel- lular mechanisms that link α7nAChR activation and pro-inflammatory cytokine production remain not well under- stood. In this study, we found that miR-124 is upregulated by cholinergic agonists in LPS-exposed cells and mice. Utilizing miR-124 mimic and siRNA knockdown, we demonstrated that miR-124 is a critical mediator for the cho- linergic anti-inflammatory action. Furthermore, our data indicated that miR-124 modulates LPS-induced cytokine production by targeting signal transducer and activator of transcription 3 （STAT3） to decrease IL-6 production and TNF-α converting enzyme （TACE） to reduce TNF-ot release. These results also indicate that miR-124 is a potential therapeutic target for the treatment of inflammatory diseases.展开更多
A large body of epidemiological and clinical evidences indicated that smoking has a protective effect in patients with ulcerative colitis （UC）. Although it is generally believed that nicotine accounts for the benefi...A large body of epidemiological and clinical evidences indicated that smoking has a protective effect in patients with ulcerative colitis （UC）. Although it is generally believed that nicotine accounts for the beneficial effect of smoking on UC, the underlying mechanism remains largely unknown. Our previously investigations demon- strated that nicotine inhibits inflammatory responses via inducing miRNA-124, which prompted us to ask whether miR-124 is involved in the protective effect of nicotine on UC. We found in the present study that nicotine elevated the level of miR-124 in epithelial colon cancer cell HT-29. MiR-124 overexpression decreased LPS-triggered STAT3 phosphorylation and STAT3 upregulation, whereas its knockdown enhanced LPS-induced p-STAT3/STAT3 increase. In mice UC model, nicotine treatment reduced weight loss, improved disease activity index, decreased HE score and increased miR-124 expression in colon tissues. Furthermore, miR-124 knockdown markedly dimin- ished the beneficial effect of nicotine in UC mice, and attenuated the inhibitory role of nicotine on the STAT3 /p- STAT3 expression in colon tissues. Consistent with its involvement in UC, biopsies samples from patients with UC also contained increased level of miR-124 when compared with that from normal individuals. These data showed that miR-124 is involved in UC and mediates the protective effects of nicotine, suggesting that the mitl-124/STAT3 is a potential target for the therapeutic intervention of UC.展开更多
MicroRNAs play pivotal roles in the regulation of both innate and adaptive immune responses. In this study, we found that activation of toll-like receptor 4 （TLR4） rapidly increased the level of microRNA-124 （miR- ...MicroRNAs play pivotal roles in the regulation of both innate and adaptive immune responses. In this study, we found that activation of toll-like receptor 4 （TLR4） rapidly increased the level of microRNA-124 （miR- 124） in lipopolysaccharide （LPS）-treated macrophages and mice. MiR-124 knockdown significantly increased the production of the pro-inflammatory cytokine TNF-oL at the post-transcriptional level in LPS-triggered macrophages. Furthermore, miR-124 knockdown or overexpression significanly increased or decreased the protein stability of TNF- α. We found miR-124 directly targeted ubiquitin-specific proteases 2 （USP2） and 14 （USP14）, two components of deubiquitinating enzymes. Knockdown of USP2 and USP14 attenuated the miR-124-mediated protein degradation of TNF-α. Together, our data identify miR-124 as an important feedback negative regulator for LPS-induced pro- duction of TNF-α by targeting USP2 and USP14, thus outlining new mechanisms for fine-tuning the TLR-triggered inflammatory response.展开更多
OBJECTIVE Although it is generally believed that nicotine accounts for the beneficial effect of smoking on ulcerative colitis,the underlying mechanisms remain not well understood.Our previous finding that nicotine inh...OBJECTIVE Although it is generally believed that nicotine accounts for the beneficial effect of smoking on ulcerative colitis,the underlying mechanisms remain not well understood.Our previous finding that nicotine inhibits inflammatory responses through inducing miRNA-124 prompted us to ask whether the miRNA is involved in the protective action of nicotine on UC.METHODS MiR-124 expres.sion in colon tissues and cells was determined by q-PCR and in situ hybridization.The effect of miR-124 on protective role of nicotine in ulcerative colitis was evaluated in DSS-treated mice and IL-6-treated Caco-2 colon epithelial cells.Expression of p-STAT3/STAT3 was detected by immunohistochemistry and Western-blot analysis.RESULTS miR-124 expression is upregulated in colon tissues from UC patients and DSS-induced colitis mice.Nicotine treatment further elevated miR-124 level in lympho.cytes isolated from human ulcerative colonic mucosa and ulcerative colon tissues from DSS mice,both in infiltrated lymphocytes and epithelial cells.Administration of nicotine also reduced weight loss,improved DAI and decreased HE score in DSS-induced colitis mice.Moreover,knockdown of miR-124 in vivo significantly diminished the beneficial effect of nicotine on murine colitis,and in vitro on IL-6-treated Caco-2 colon epithelial cells.Further analysis indicated that nicotine inhibited STAT3 activation in vivo and in IL-6-treated Caco-2 colon epithelial cells and Jurkat human T lymphocytes,in which miR-124 knockdown led to increased activation of STAT3.Blocking STAT3 activity alone is beneficial for DSS colitis and also abolished nicotine′s protective effect in this model.CONCLUSION These data indicated that nicotine exerts its protective action in UC through inducing miR-124 and its effect on STAT3,and suggest that the miR-124/STAT3 system is a potential target for the therapeutic intervention of UC.展开更多
目的探究MicroRNA-124(miR-124)对脑缺血损伤小鼠神经功能的改善作用及其内在机制。方法①取32只C57小鼠随机分为假手术组和脑缺血组(n=16),TTC染色和神经行为学评分检测小鼠脑损伤后3天脑梗死面积和运动情况,RT-qPCR检测miR-124在两组...目的探究MicroRNA-124(miR-124)对脑缺血损伤小鼠神经功能的改善作用及其内在机制。方法①取32只C57小鼠随机分为假手术组和脑缺血组(n=16),TTC染色和神经行为学评分检测小鼠脑损伤后3天脑梗死面积和运动情况,RT-qPCR检测miR-124在两组间的表达变化。②培养原代神经元细胞,通过氧糖剥夺模拟缺血再灌注损伤,观察氧糖剥夺后0、72 h miR-124的变化趋势。③另取32只C57小鼠随机分为脑缺血组和脑缺血+miR-124组(n=16),TTC染色、转棒实验和肢体放置实验检测小鼠的运动功能改善情况。④细胞实验分为氧糖剥夺组和氧糖剥夺+miR-124组,通过免疫荧光实验检测两组神经元轴突的生长情况。Targetscan数据库预测miR-124下游靶基因,双荧光素酶基因报告和Western blot在原代神经元等上验证对照组和miR-124组下游靶基因第10号染色体缺失的磷酸酶及张力蛋白同源基因(the phosphate and tensin homolog deleted on chromosome ten,PTEN)的表达变化。上调PTEN,检测氧糖剥夺+miR-124和氧糖剥夺+miR-124+PTEN两组神经元轴突的生长情况。(5)在体实验中检测脑缺血+miR-124组和脑缺血+miR-124+Pten组(n=8)转棒实验和肢体放置情况。结果脑缺血再灌注后,小鼠脑梗死面积约达到40%(P<0.001),小鼠的神经认知功能显著降低(P<0.001),已达到重度认知功能损害;miR-124的表达较对照组明显升高(P<0.05);而进一步过表达miR-124能够促进氧糖剥夺后神经元轴突的生长(P<0.05),显著缩小脑梗死面积(P<0.05),且促进动物运动能力的恢复和改善(P<0.05);Targetscan数据库预测miR-124下游靶基因为PTEN,双荧光素酶基因报告和Western blot都证实miR-124能有效下调PTEN的表达(P<0.05);最后,上调PTEN逆转了miR-124促进神经元轴突的生长以及改善小鼠运动能力的效应(P<0.05)。结论miR-124通过下调PTEN促进脑缺血小鼠神经元轴突生长,且有助于小鼠运动功能的恢复。展开更多
OBJECTIVE MicroR NA(miR NA)holds promise as a novel therapeutic tool for cancer treatment.However,the transfection efficiency of current delivery systems represents a bottleneck for clinical applications.Here,we demon...OBJECTIVE MicroR NA(miR NA)holds promise as a novel therapeutic tool for cancer treatment.However,the transfection efficiency of current delivery systems represents a bottleneck for clinical applications.Here,we demonstrate that gap junctions mediate an augmentative effect on the antiproliferation mediated by mi R-124-3p in U87 and C6 glioblastoma cells.METHODS The functional inhibition of gap junctions using either si RNA or pharmacological inhibition eliminated the mi R-124-3p-mediated antiproliferation,whereas the enhancement of gap junctions with retinoic acid treatment augmented this mi R-124-3p-mediated antiproliferation.A similar effect was observed in glioblastoma xenograft models.RESULTS More importantly,patch clamp and co-culture assays demonstrated the transmission of mi R-124-3p through gap junction channels into adjacent cells.In further exploring the impact of gap junction-mediated transport of mi R-124-3p on mi R-124-3p target pathways,we found that mi R-124-3p inhibited glioblastoma cell growth in part by decreasing the protein expression of cyclindependent kinase 6,leading to cel cycle arrest at the G0/G1phase;moreover,pharmacological regulation of gap junctions affected this cell cycle arrest.CONCLUSION Our results indicate that the″bystander″effects of functional gap junctions composed of connexin 43 enhance the antitumor effect of mi R-124-3p in glioblastoma cells by transferring mi R-124-3p to adjacent cells,thereby enhancing G0/G1cell cycle arrest.These observations provide a new guiding strategy for the clinical application of mi RNA therapy in tumor treatment.展开更多
基金supported by National Natural Science Foundation of China(81273606,81473259 to XL,81603116 to YS)National Science and Technology Major Project(2014ZX09J14103-08C to XL)
文摘OBJECTIVE Although it is generally believed that nicotine accounts for the beneficial effect of smoking on ulcerative colitis,the underlying mechanisms remain not well-understood.Our previous finding that nicotine inhibits inflammatory responses through inducing miRNA-124 prompted us to ask whether the miRNA is involved in the protective action of nicotine on UC.METHODS Mi R-124 expression in colon tissues and cells was determined by q-PCR and in situ hybridization.The effect of miR-124 on protective role of nicotine in ulcerative colitis was evaluated in DSS-treated mice and IL-6-treated Caco-2 colon epithelial cells.Expression of p-STAT3/STAT3 was detected by immunohistochemistry and Western blot analysis.RESULTS miR-124 expression is upregulated in colon tissues from patients and DSS-induced colitis.Nicotine treatment further elevated miR-124 level in colon tissues of the mice,in infiltrated lymphocytes and epithelial cells,and augmented miR-124 expression in lymphocytes isolated from human ulcerative colon tissues.Administration of nicotine also reduced weight loss,improved DAI and decreased HE score in DSS-induced colitis.Moreover,knockdown of miR-124 in vivo significantly diminished the beneficial effect of nicotine,and in vitro on IL-6-treated Caco-2 colon epithelial cells.Further analysis indicated that nicotine inhibited STAT3 activation in vivo and in IL-6-treated Caco-2 colon epithelial cells and Jurkat human T lymphocytes,in whichmiR-124 knockdown led to increased activation of STAT3.CONCLUSION These data indicated that nicotine exerts its protective action in UC through inducing miR-124 and its effect on STAT3,suggesting that the miR-124/STAT3 system is a potential target for the therapeutic intervention of UC.
文摘The vagus nerve can control inflammatory response through a ＇ cholinergic anti-inflammatory pathway＇, which is mediated by the α7-nicotinic acetylcholine receptor （α7nAChR） on macrophages. However, the intracel- lular mechanisms that link α7nAChR activation and pro-inflammatory cytokine production remain not well under- stood. In this study, we found that miR-124 is upregulated by cholinergic agonists in LPS-exposed cells and mice. Utilizing miR-124 mimic and siRNA knockdown, we demonstrated that miR-124 is a critical mediator for the cho- linergic anti-inflammatory action. Furthermore, our data indicated that miR-124 modulates LPS-induced cytokine production by targeting signal transducer and activator of transcription 3 （STAT3） to decrease IL-6 production and TNF-α converting enzyme （TACE） to reduce TNF-ot release. These results also indicate that miR-124 is a potential therapeutic target for the treatment of inflammatory diseases.
文摘A large body of epidemiological and clinical evidences indicated that smoking has a protective effect in patients with ulcerative colitis （UC）. Although it is generally believed that nicotine accounts for the beneficial effect of smoking on UC, the underlying mechanism remains largely unknown. Our previously investigations demon- strated that nicotine inhibits inflammatory responses via inducing miRNA-124, which prompted us to ask whether miR-124 is involved in the protective effect of nicotine on UC. We found in the present study that nicotine elevated the level of miR-124 in epithelial colon cancer cell HT-29. MiR-124 overexpression decreased LPS-triggered STAT3 phosphorylation and STAT3 upregulation, whereas its knockdown enhanced LPS-induced p-STAT3/STAT3 increase. In mice UC model, nicotine treatment reduced weight loss, improved disease activity index, decreased HE score and increased miR-124 expression in colon tissues. Furthermore, miR-124 knockdown markedly dimin- ished the beneficial effect of nicotine in UC mice, and attenuated the inhibitory role of nicotine on the STAT3 /p- STAT3 expression in colon tissues. Consistent with its involvement in UC, biopsies samples from patients with UC also contained increased level of miR-124 when compared with that from normal individuals. These data showed that miR-124 is involved in UC and mediates the protective effects of nicotine, suggesting that the mitl-124/STAT3 is a potential target for the therapeutic intervention of UC.
文摘MicroRNAs play pivotal roles in the regulation of both innate and adaptive immune responses. In this study, we found that activation of toll-like receptor 4 （TLR4） rapidly increased the level of microRNA-124 （miR- 124） in lipopolysaccharide （LPS）-treated macrophages and mice. MiR-124 knockdown significantly increased the production of the pro-inflammatory cytokine TNF-oL at the post-transcriptional level in LPS-triggered macrophages. Furthermore, miR-124 knockdown or overexpression significanly increased or decreased the protein stability of TNF- α. We found miR-124 directly targeted ubiquitin-specific proteases 2 （USP2） and 14 （USP14）, two components of deubiquitinating enzymes. Knockdown of USP2 and USP14 attenuated the miR-124-mediated protein degradation of TNF-α. Together, our data identify miR-124 as an important feedback negative regulator for LPS-induced pro- duction of TNF-α by targeting USP2 and USP14, thus outlining new mechanisms for fine-tuning the TLR-triggered inflammatory response.
基金supported by National Natural Science Foundation of China(8147325981603116)
文摘OBJECTIVE Although it is generally believed that nicotine accounts for the beneficial effect of smoking on ulcerative colitis,the underlying mechanisms remain not well understood.Our previous finding that nicotine inhibits inflammatory responses through inducing miRNA-124 prompted us to ask whether the miRNA is involved in the protective action of nicotine on UC.METHODS MiR-124 expres.sion in colon tissues and cells was determined by q-PCR and in situ hybridization.The effect of miR-124 on protective role of nicotine in ulcerative colitis was evaluated in DSS-treated mice and IL-6-treated Caco-2 colon epithelial cells.Expression of p-STAT3/STAT3 was detected by immunohistochemistry and Western-blot analysis.RESULTS miR-124 expression is upregulated in colon tissues from UC patients and DSS-induced colitis mice.Nicotine treatment further elevated miR-124 level in lympho.cytes isolated from human ulcerative colonic mucosa and ulcerative colon tissues from DSS mice,both in infiltrated lymphocytes and epithelial cells.Administration of nicotine also reduced weight loss,improved DAI and decreased HE score in DSS-induced colitis mice.Moreover,knockdown of miR-124 in vivo significantly diminished the beneficial effect of nicotine on murine colitis,and in vitro on IL-6-treated Caco-2 colon epithelial cells.Further analysis indicated that nicotine inhibited STAT3 activation in vivo and in IL-6-treated Caco-2 colon epithelial cells and Jurkat human T lymphocytes,in which miR-124 knockdown led to increased activation of STAT3.Blocking STAT3 activity alone is beneficial for DSS colitis and also abolished nicotine′s protective effect in this model.CONCLUSION These data indicated that nicotine exerts its protective action in UC through inducing miR-124 and its effect on STAT3,and suggest that the miR-124/STAT3 system is a potential target for the therapeutic intervention of UC.
文摘目的探究MicroRNA-124(miR-124)对脑缺血损伤小鼠神经功能的改善作用及其内在机制。方法①取32只C57小鼠随机分为假手术组和脑缺血组(n=16),TTC染色和神经行为学评分检测小鼠脑损伤后3天脑梗死面积和运动情况,RT-qPCR检测miR-124在两组间的表达变化。②培养原代神经元细胞,通过氧糖剥夺模拟缺血再灌注损伤,观察氧糖剥夺后0、72 h miR-124的变化趋势。③另取32只C57小鼠随机分为脑缺血组和脑缺血+miR-124组(n=16),TTC染色、转棒实验和肢体放置实验检测小鼠的运动功能改善情况。④细胞实验分为氧糖剥夺组和氧糖剥夺+miR-124组,通过免疫荧光实验检测两组神经元轴突的生长情况。Targetscan数据库预测miR-124下游靶基因,双荧光素酶基因报告和Western blot在原代神经元等上验证对照组和miR-124组下游靶基因第10号染色体缺失的磷酸酶及张力蛋白同源基因(the phosphate and tensin homolog deleted on chromosome ten,PTEN)的表达变化。上调PTEN,检测氧糖剥夺+miR-124和氧糖剥夺+miR-124+PTEN两组神经元轴突的生长情况。(5)在体实验中检测脑缺血+miR-124组和脑缺血+miR-124+Pten组(n=8)转棒实验和肢体放置情况。结果脑缺血再灌注后,小鼠脑梗死面积约达到40%(P<0.001),小鼠的神经认知功能显著降低(P<0.001),已达到重度认知功能损害;miR-124的表达较对照组明显升高(P<0.05);而进一步过表达miR-124能够促进氧糖剥夺后神经元轴突的生长(P<0.05),显著缩小脑梗死面积(P<0.05),且促进动物运动能力的恢复和改善(P<0.05);Targetscan数据库预测miR-124下游靶基因为PTEN,双荧光素酶基因报告和Western blot都证实miR-124能有效下调PTEN的表达(P<0.05);最后,上调PTEN逆转了miR-124促进神经元轴突的生长以及改善小鼠运动能力的效应(P<0.05)。结论miR-124通过下调PTEN促进脑缺血小鼠神经元轴突生长,且有助于小鼠运动功能的恢复。
基金The project supported by National Natural Science Foundation of China(81473234,U1303221)
文摘OBJECTIVE MicroR NA(miR NA)holds promise as a novel therapeutic tool for cancer treatment.However,the transfection efficiency of current delivery systems represents a bottleneck for clinical applications.Here,we demonstrate that gap junctions mediate an augmentative effect on the antiproliferation mediated by mi R-124-3p in U87 and C6 glioblastoma cells.METHODS The functional inhibition of gap junctions using either si RNA or pharmacological inhibition eliminated the mi R-124-3p-mediated antiproliferation,whereas the enhancement of gap junctions with retinoic acid treatment augmented this mi R-124-3p-mediated antiproliferation.A similar effect was observed in glioblastoma xenograft models.RESULTS More importantly,patch clamp and co-culture assays demonstrated the transmission of mi R-124-3p through gap junction channels into adjacent cells.In further exploring the impact of gap junction-mediated transport of mi R-124-3p on mi R-124-3p target pathways,we found that mi R-124-3p inhibited glioblastoma cell growth in part by decreasing the protein expression of cyclindependent kinase 6,leading to cel cycle arrest at the G0/G1phase;moreover,pharmacological regulation of gap junctions affected this cell cycle arrest.CONCLUSION Our results indicate that the″bystander″effects of functional gap junctions composed of connexin 43 enhance the antitumor effect of mi R-124-3p in glioblastoma cells by transferring mi R-124-3p to adjacent cells,thereby enhancing G0/G1cell cycle arrest.These observations provide a new guiding strategy for the clinical application of mi RNA therapy in tumor treatment.
