Background: cAMP response element-binding protein (CREB) is one of the cellular transcription factors found in neurons. CREB is also important for the survival of neurons, and has an important role in the development ...Background: cAMP response element-binding protein (CREB) is one of the cellular transcription factors found in neurons. CREB is also important for the survival of neurons, and has an important role in the development of drug addiction. Datura stramonium (DS) is a tropical ubiquitous plant commonly used to increase the intoxication of certain beverages for recreational purposes. The seeds of this plant are very toxic and may produce addiction on prolong usage. This research investigated the effects of administration of high doses of DS seeds on the expression of CREB protein in both male and female rats’ frontal cortices and its implication in addiction and neurodegeneration. Materials and Methods: The study was conducted with a total of 24 male and female Wistar rats weighing 200 g - 250 g. The rats were divided into three groups of 8 rats each. Each group was further divided into four sub-groups of 2 rats each. Ethanolic dried seed extract of DS was diluted in normal saline and administered intraperitoneally (i.p.) to the treatment groups. The treated sub-groups received 750 mg/kg of DS extract<sup> </sup>once in group 1, twice in group 2 and thrice in group 3 daily for 4 weeks respectively, while the control sub-groups received i.p. normal saline concurrently for the same duration of time. The rats were euthanized and an analysis of variance (ANOVA) was computed to detect a significant main difference of DS effect on CREB expression for each group, while post hoc Bonferroni Test compared CREB protein expression between male and female groups. Result: There were significant differences in the expression of CREB protein between the sub-groups and between the male and female rats of treated sub-group (p < 0.05) compared to the controls. There was a decrease in the female treated sub-groups and an increase in the male treated sub-groups compared to the respective controls. Conclusion: High doses of DS administration for a prolong time may affect the expressions of CREB protein differently in male and female treated rats which may consequently lead to addiction and neurodegeneration affecting frontal cortex neurons.展开更多
Objective:Gastric cancer(GC)is a globally common cancer characterized by high incidence and mortality worldwide.Advances in the molecular understanding of GC provide promising targets for GC diagnosis and therapy.Long...Objective:Gastric cancer(GC)is a globally common cancer characterized by high incidence and mortality worldwide.Advances in the molecular understanding of GC provide promising targets for GC diagnosis and therapy.Long non-coding RNAs(lncRNAs)and their downstream regulators are regarded to be implicated in the progression of multiple types of malignancies.Studies have shown that the lncRNA small nucleolar RNA host gene 4(SNHG4)serves as a tumor promoter in various malignancies,while its function in GC has yet to be characterized.Therefore,our study aimed to explore the role and underlying mechanism of SNHG4 in GC.Methods:We used qRT-PCR to analyze SNHG4 expression in GC tissues and cells.Kaplan-Meier analysis was used to assess the correlation between SNHG4 expression and the survival rate of GC patients.Cellular function experiments such as CCK-8,BrdU,colony formation,flow cytometry analysis,and transwell were performed to explore the effects of SNHG4 on GC cell proliferation,apoptosis,cell cycle,migration,and invasion.We also established xenograft mouse models to explore the effect of SNHG4 on GC tumor growth.Mechanically,dual luciferase reporter assay was used to verify the interaction between SNHG4 and miR-409-3p and between miR-409-3p and cAMP responsive element binding protein 1(CREB1).Results:The results indicated that SNHG4 was overexpressed in GC tissues and cell lines,and was linked with poor survival rate of GC patients.SNHG4 promoted GC cell proliferation,migration,and invasion while inhibiting cell apoptosis and cell cycle arrest in vitro.The in vivo experiment indicated that SNHG4 facilitated GC tumor growth.Furthermore,SNHG4 was demonstrated to bind to miR-409-3p.Moreover,CREB1 was directly targeted by miR-409-3p.Rescue assays demonstrated that miR-409-3p deficiency reversed the suppressive impact of SNHG4 knockdown on GC cell malignancy.Additionally,miR-409-3p was also revealed to inhibit GC cell proliferation,migration,and invasion by targeting CREB1.Conclusion:In conclusion,we verified that the SNHG4 promoted GC growth and metastasis by binding to miR-409-3p to upregulate CREB1,which may deepen the understanding of the underlying mechanism in GC development.展开更多
This paper reviews the distinctive roles played by the transcriptional coactivators CREB-binding protein(CBP) and p300 in Wnt/β-catenin signaling and cell physiology in colorectal cancer(CRC). Specifically, we focus ...This paper reviews the distinctive roles played by the transcriptional coactivators CREB-binding protein(CBP) and p300 in Wnt/β-catenin signaling and cell physiology in colorectal cancer(CRC). Specifically, we focus on the effects of CBP- and p300-mediated Wnt activity on(1) neoplastic progression;(2) the activities of butyrate, a breakdown product of dietary fiber, on cell signaling and colonic cell physiology;(3) the development of resistance to histone deacetylase inhibitors(HDACis), including butyrate and synthetic HDACis, in colonic cells; and(4) the physiology and number of cancer stem cells. Mutations of the Wnt/β-catenin signaling pathway initiate the majority of CRC cases, and we have shown that hyperactivation of this pathway by butyrate and other HDACis promotes CRC cell apoptosis. This activity by butyrate may in part explain the preventive action of fiber against CRC. However, individuals with a high-fiber diet may still develop neoplasia; therefore, resistance to the chemopreventive action of butyrate likely contributes to CRC. CBP or p300 may modify the ability of butyrate to influence colonic cell physiology since the two transcriptional coactivators affect Wnt signaling, and likely, its hyperactivation by butyrate. Also, CBP and p300 likely affect colonic tumorigenesis, as well as stem cell pluripotency. Improvement of CRC prevention and therapy requires a better understanding of the alterations in Wnt signaling and gene expression that underlie neoplastic progression, stem cell fate, and the development of resistance to butyrate and clinically relevant HDACis. Detailed knowledge of how CBP- and p300 modulate colonic cell physiology may lead to new approaches for anti-CRC prevention and therapeutics, particularly with respect to combinatorial therapy of CBP/p300 inhibitors with HDACis.展开更多
This study examined the effect of GHRP-6, a known GHSs receptor agonist, on the phosphorylation of cAMP-responsive element-binding protein （CREB） and the tmderly mechanism. GH3 cells were cultured and subjected to d...This study examined the effect of GHRP-6, a known GHSs receptor agonist, on the phosphorylation of cAMP-responsive element-binding protein （CREB） and the tmderly mechanism. GH3 cells were cultured and subjected to different treatments as follows： GHRP-6, GHRP-6 plus GHRH, phorbol ester （PMA）, an activator of PKC, alone or in combination with GHRP-6, G66983, a general inhibitor of PKCs, in the presence or absence of GHRP-6, rottlerin, an inhibitor of PKCs, alone or plus GHRP-6. The cells were transiently transfected with PKCσ-specific siRNA and then treated with GHRP-6. GH level was measured by enzyme-linked immunosorbent assay （ELISA）. The expression of phosphor-CREB, PKCσ, PKC0 and phosphor-PKCo was determined by Western blotting. The results showed that GHRP-6 stimulated GH secretion in both time- and dose-dependent manners and enhanced the effect of GHRH on GH secretion. GHRP-6 was also found to induce CREB phosphorylation. Moreover, GH secretion was enhanced by the PKC activator PMA and reduced by the PKC inhibitors （G66983, rottlerin） and knockdown of PKCσ. PKCσ could be activated by GHRP-6. It is concluded that PKC, especialiy PKCσ, mediates CREB phosphorylation and GHRP-6-induced GH secretion.展开更多
Objective:To investigate the regulatory role of cyclic adenosine monophosphate responsive element binding protein(CREB)/brain-derived neurotrophic factor(BDNF)signaling pathway in acute sleep deprivation(SD)-induced a...Objective:To investigate the regulatory role of cyclic adenosine monophosphate responsive element binding protein(CREB)/brain-derived neurotrophic factor(BDNF)signaling pathway in acute sleep deprivation(SD)-induced anxiety-like behavior mice(SD group)to study the mechanism of anxiety-like behavior better.Methods:The SD chamber was used to deprive the mice of sleep,and the anxiety-like behavior of the mice was verified using an open field test(OFT),elevated plus maze(EPM),forced swim test(FST),and tail suspension test(TST).Finally,proteins were detected by Western blotting.Result:OFT showed that the active distance and the time of stay in the central area were significantly reduced(P<0.05).EPM showed that the time and number of open arms in the SD group were significantly lower than in the control group(P<0.05).The FST showed that the forced swimming immobility time of the SD group was significantly lower than that of the control(P<0.05).Moreover,the TST showed that the immobility time of the tail suspension experiment in the SD group was significantly higher than that in the control group(P<0.05).Conclusion:Acute SD can regulate anxiety-like behavior in mice through the CREB/BDNF signaling pathway.展开更多
cAMP应答元件结合蛋白(cAMP response element binding protein,CREB)在神经元生成、突触可塑性及学习记忆等方面都具有重要的调节作用,这使得与CREB信号通路相关的分子成为较受关注的神经系统疾病干预的药物靶点.本文概述了CREB的基本...cAMP应答元件结合蛋白(cAMP response element binding protein,CREB)在神经元生成、突触可塑性及学习记忆等方面都具有重要的调节作用,这使得与CREB信号通路相关的分子成为较受关注的神经系统疾病干预的药物靶点.本文概述了CREB的基本构成、相关信号通路、其目的基因表达调控及其在阿尔茨海默病(Alzheimer’s disease,AD)中的作用.展开更多
目的:探讨微小RNA-302c(miR-302c)在肺癌组织中的表达,以及对肺癌侵袭和迁移的影响和作用机制。方法:在线分析GEO数据库中GSE19945和GSE136043两组肺癌数据集中miR-302c的表达情况,通过Human Protein Atlas数据库研究CREB1表达情况;双...目的:探讨微小RNA-302c(miR-302c)在肺癌组织中的表达,以及对肺癌侵袭和迁移的影响和作用机制。方法:在线分析GEO数据库中GSE19945和GSE136043两组肺癌数据集中miR-302c的表达情况,通过Human Protein Atlas数据库研究CREB1表达情况;双荧光素酶实验证明miR-302c和CREB1的关系。正常组细胞不加任何药物,对照组细胞转染miR-302cmimic-NC,实验组细胞转染miR-302c-mimic。通过Transwell小室检测细胞的侵袭与迁移能力,通过小管形成检测细胞的血管生成能力,通过Western blot检测各组细胞中CREB1、p-P53、p-P21的表达水平。结果:生物信息分析显示,与正常组织相比,miR-302c在肺癌组织、肺癌淋巴转移组织中的表达明显降低,肺癌组织中CREB1的表达明显升高;双荧光素酶实验证明miR-302c靶向调控CREB1的表达;与正常组相比,实验组迁移和侵袭的细胞数量、小管生成的数量明显下降,实验组中CREB1的表达明显下降,p-P53、p-P21的表达明显升高(均P<0.05)。结论:miR-302c在肺癌组织表达降低,过表达miR-302c后能明显抑制肺癌细胞的侵袭与转移,这可能与抑制靶基因CREB1的表达,以及激活P53信号通路有关。展开更多
乙型肝炎病毒X蛋白(hepatitis B virus X protein,HBx)对肝癌的发生发展具有十分重要的作用.HBx具有促进肝癌迁移的作用,但其作用的分子机制不清.本研究对HBx促进肝癌细胞迁移的分子机制进行了探讨.伤口愈合和Boyden’s chamber结果表明...乙型肝炎病毒X蛋白(hepatitis B virus X protein,HBx)对肝癌的发生发展具有十分重要的作用.HBx具有促进肝癌迁移的作用,但其作用的分子机制不清.本研究对HBx促进肝癌细胞迁移的分子机制进行了探讨.伤口愈合和Boyden’s chamber结果表明,HBx可明显促进肝癌Hep G2细胞迁移.在稳定转染HBx的Hep G2(Hep G2-X)细胞中转染HBx结合蛋白(hepatitis B X-interacting protein,HBXIP)的RNA干扰片段,可明显抑制HBx的促迁移作用.免疫组化和实时定量PCR结果表明,HBXIP在肝癌组织中显著高表达,并且与HBx表达成正相关.荧光素酶报告基因和免疫印迹结果表明,HBx显著增强HBXIP的启动子活性和蛋白质表达水平.应用HBx的RNA干扰处理Hep G2-X细胞,HBXIP的启动子活性和蛋白质表达水平明显下降.将HBXIP启动子区的c AMP效应元件结合因子(CREB)结合位点突变后,HBx上调HBXIP的作用消失.应用CREB的RNA干扰处理肝癌细胞,在启动子水平和蛋白质水平上,HBx对HBXIP的上调作用被显著抑制.染色质免疫共沉淀结果表明,HBx能够通过CREB结合到HBXIP的启动子上,进而发挥激活HBXIP的功能.本研究结果表明,HBx促进肝癌细胞迁移的作用是通过CREB上调HBXIP实现的.这一发现对进一步揭示HBx促进肝癌细胞迁移的分子机制具有重要意义.展开更多
文摘Background: cAMP response element-binding protein (CREB) is one of the cellular transcription factors found in neurons. CREB is also important for the survival of neurons, and has an important role in the development of drug addiction. Datura stramonium (DS) is a tropical ubiquitous plant commonly used to increase the intoxication of certain beverages for recreational purposes. The seeds of this plant are very toxic and may produce addiction on prolong usage. This research investigated the effects of administration of high doses of DS seeds on the expression of CREB protein in both male and female rats’ frontal cortices and its implication in addiction and neurodegeneration. Materials and Methods: The study was conducted with a total of 24 male and female Wistar rats weighing 200 g - 250 g. The rats were divided into three groups of 8 rats each. Each group was further divided into four sub-groups of 2 rats each. Ethanolic dried seed extract of DS was diluted in normal saline and administered intraperitoneally (i.p.) to the treatment groups. The treated sub-groups received 750 mg/kg of DS extract<sup> </sup>once in group 1, twice in group 2 and thrice in group 3 daily for 4 weeks respectively, while the control sub-groups received i.p. normal saline concurrently for the same duration of time. The rats were euthanized and an analysis of variance (ANOVA) was computed to detect a significant main difference of DS effect on CREB expression for each group, while post hoc Bonferroni Test compared CREB protein expression between male and female groups. Result: There were significant differences in the expression of CREB protein between the sub-groups and between the male and female rats of treated sub-group (p < 0.05) compared to the controls. There was a decrease in the female treated sub-groups and an increase in the male treated sub-groups compared to the respective controls. Conclusion: High doses of DS administration for a prolong time may affect the expressions of CREB protein differently in male and female treated rats which may consequently lead to addiction and neurodegeneration affecting frontal cortex neurons.
文摘Objective:Gastric cancer(GC)is a globally common cancer characterized by high incidence and mortality worldwide.Advances in the molecular understanding of GC provide promising targets for GC diagnosis and therapy.Long non-coding RNAs(lncRNAs)and their downstream regulators are regarded to be implicated in the progression of multiple types of malignancies.Studies have shown that the lncRNA small nucleolar RNA host gene 4(SNHG4)serves as a tumor promoter in various malignancies,while its function in GC has yet to be characterized.Therefore,our study aimed to explore the role and underlying mechanism of SNHG4 in GC.Methods:We used qRT-PCR to analyze SNHG4 expression in GC tissues and cells.Kaplan-Meier analysis was used to assess the correlation between SNHG4 expression and the survival rate of GC patients.Cellular function experiments such as CCK-8,BrdU,colony formation,flow cytometry analysis,and transwell were performed to explore the effects of SNHG4 on GC cell proliferation,apoptosis,cell cycle,migration,and invasion.We also established xenograft mouse models to explore the effect of SNHG4 on GC tumor growth.Mechanically,dual luciferase reporter assay was used to verify the interaction between SNHG4 and miR-409-3p and between miR-409-3p and cAMP responsive element binding protein 1(CREB1).Results:The results indicated that SNHG4 was overexpressed in GC tissues and cell lines,and was linked with poor survival rate of GC patients.SNHG4 promoted GC cell proliferation,migration,and invasion while inhibiting cell apoptosis and cell cycle arrest in vitro.The in vivo experiment indicated that SNHG4 facilitated GC tumor growth.Furthermore,SNHG4 was demonstrated to bind to miR-409-3p.Moreover,CREB1 was directly targeted by miR-409-3p.Rescue assays demonstrated that miR-409-3p deficiency reversed the suppressive impact of SNHG4 knockdown on GC cell malignancy.Additionally,miR-409-3p was also revealed to inhibit GC cell proliferation,migration,and invasion by targeting CREB1.Conclusion:In conclusion,we verified that the SNHG4 promoted GC growth and metastasis by binding to miR-409-3p to upregulate CREB1,which may deepen the understanding of the underlying mechanism in GC development.
基金Supported by National Institutes of Health(Bethesda,MD)National Cancer Institute,No.1R15CA149589-01
文摘This paper reviews the distinctive roles played by the transcriptional coactivators CREB-binding protein(CBP) and p300 in Wnt/β-catenin signaling and cell physiology in colorectal cancer(CRC). Specifically, we focus on the effects of CBP- and p300-mediated Wnt activity on(1) neoplastic progression;(2) the activities of butyrate, a breakdown product of dietary fiber, on cell signaling and colonic cell physiology;(3) the development of resistance to histone deacetylase inhibitors(HDACis), including butyrate and synthetic HDACis, in colonic cells; and(4) the physiology and number of cancer stem cells. Mutations of the Wnt/β-catenin signaling pathway initiate the majority of CRC cases, and we have shown that hyperactivation of this pathway by butyrate and other HDACis promotes CRC cell apoptosis. This activity by butyrate may in part explain the preventive action of fiber against CRC. However, individuals with a high-fiber diet may still develop neoplasia; therefore, resistance to the chemopreventive action of butyrate likely contributes to CRC. CBP or p300 may modify the ability of butyrate to influence colonic cell physiology since the two transcriptional coactivators affect Wnt signaling, and likely, its hyperactivation by butyrate. Also, CBP and p300 likely affect colonic tumorigenesis, as well as stem cell pluripotency. Improvement of CRC prevention and therapy requires a better understanding of the alterations in Wnt signaling and gene expression that underlie neoplastic progression, stem cell fate, and the development of resistance to butyrate and clinically relevant HDACis. Detailed knowledge of how CBP- and p300 modulate colonic cell physiology may lead to new approaches for anti-CRC prevention and therapeutics, particularly with respect to combinatorial therapy of CBP/p300 inhibitors with HDACis.
基金supported by a grant from the National Natural Sciences Foundation of China (No. 30672161)
文摘This study examined the effect of GHRP-6, a known GHSs receptor agonist, on the phosphorylation of cAMP-responsive element-binding protein （CREB） and the tmderly mechanism. GH3 cells were cultured and subjected to different treatments as follows： GHRP-6, GHRP-6 plus GHRH, phorbol ester （PMA）, an activator of PKC, alone or in combination with GHRP-6, G66983, a general inhibitor of PKCs, in the presence or absence of GHRP-6, rottlerin, an inhibitor of PKCs, alone or plus GHRP-6. The cells were transiently transfected with PKCσ-specific siRNA and then treated with GHRP-6. GH level was measured by enzyme-linked immunosorbent assay （ELISA）. The expression of phosphor-CREB, PKCσ, PKC0 and phosphor-PKCo was determined by Western blotting. The results showed that GHRP-6 stimulated GH secretion in both time- and dose-dependent manners and enhanced the effect of GHRH on GH secretion. GHRP-6 was also found to induce CREB phosphorylation. Moreover, GH secretion was enhanced by the PKC activator PMA and reduced by the PKC inhibitors （G66983, rottlerin） and knockdown of PKCσ. PKCσ could be activated by GHRP-6. It is concluded that PKC, especialiy PKCσ, mediates CREB phosphorylation and GHRP-6-induced GH secretion.
文摘Objective:To investigate the regulatory role of cyclic adenosine monophosphate responsive element binding protein(CREB)/brain-derived neurotrophic factor(BDNF)signaling pathway in acute sleep deprivation(SD)-induced anxiety-like behavior mice(SD group)to study the mechanism of anxiety-like behavior better.Methods:The SD chamber was used to deprive the mice of sleep,and the anxiety-like behavior of the mice was verified using an open field test(OFT),elevated plus maze(EPM),forced swim test(FST),and tail suspension test(TST).Finally,proteins were detected by Western blotting.Result:OFT showed that the active distance and the time of stay in the central area were significantly reduced(P<0.05).EPM showed that the time and number of open arms in the SD group were significantly lower than in the control group(P<0.05).The FST showed that the forced swimming immobility time of the SD group was significantly lower than that of the control(P<0.05).Moreover,the TST showed that the immobility time of the tail suspension experiment in the SD group was significantly higher than that in the control group(P<0.05).Conclusion:Acute SD can regulate anxiety-like behavior in mice through the CREB/BDNF signaling pathway.
文摘目的:探讨微小RNA-302c(miR-302c)在肺癌组织中的表达,以及对肺癌侵袭和迁移的影响和作用机制。方法:在线分析GEO数据库中GSE19945和GSE136043两组肺癌数据集中miR-302c的表达情况,通过Human Protein Atlas数据库研究CREB1表达情况;双荧光素酶实验证明miR-302c和CREB1的关系。正常组细胞不加任何药物,对照组细胞转染miR-302cmimic-NC,实验组细胞转染miR-302c-mimic。通过Transwell小室检测细胞的侵袭与迁移能力,通过小管形成检测细胞的血管生成能力,通过Western blot检测各组细胞中CREB1、p-P53、p-P21的表达水平。结果:生物信息分析显示,与正常组织相比,miR-302c在肺癌组织、肺癌淋巴转移组织中的表达明显降低,肺癌组织中CREB1的表达明显升高;双荧光素酶实验证明miR-302c靶向调控CREB1的表达;与正常组相比,实验组迁移和侵袭的细胞数量、小管生成的数量明显下降,实验组中CREB1的表达明显下降,p-P53、p-P21的表达明显升高(均P<0.05)。结论:miR-302c在肺癌组织表达降低,过表达miR-302c后能明显抑制肺癌细胞的侵袭与转移,这可能与抑制靶基因CREB1的表达,以及激活P53信号通路有关。
文摘乙型肝炎病毒X蛋白(hepatitis B virus X protein,HBx)对肝癌的发生发展具有十分重要的作用.HBx具有促进肝癌迁移的作用,但其作用的分子机制不清.本研究对HBx促进肝癌细胞迁移的分子机制进行了探讨.伤口愈合和Boyden’s chamber结果表明,HBx可明显促进肝癌Hep G2细胞迁移.在稳定转染HBx的Hep G2(Hep G2-X)细胞中转染HBx结合蛋白(hepatitis B X-interacting protein,HBXIP)的RNA干扰片段,可明显抑制HBx的促迁移作用.免疫组化和实时定量PCR结果表明,HBXIP在肝癌组织中显著高表达,并且与HBx表达成正相关.荧光素酶报告基因和免疫印迹结果表明,HBx显著增强HBXIP的启动子活性和蛋白质表达水平.应用HBx的RNA干扰处理Hep G2-X细胞,HBXIP的启动子活性和蛋白质表达水平明显下降.将HBXIP启动子区的c AMP效应元件结合因子(CREB)结合位点突变后,HBx上调HBXIP的作用消失.应用CREB的RNA干扰处理肝癌细胞,在启动子水平和蛋白质水平上,HBx对HBXIP的上调作用被显著抑制.染色质免疫共沉淀结果表明,HBx能够通过CREB结合到HBXIP的启动子上,进而发挥激活HBXIP的功能.本研究结果表明,HBx促进肝癌细胞迁移的作用是通过CREB上调HBXIP实现的.这一发现对进一步揭示HBx促进肝癌细胞迁移的分子机制具有重要意义.
