BACKGROUND： The p25-activated cyclin-dependent protein kinase 5 （Cdk5） may induce neuronal cell death and cause the development of dementia following cerebral ischemia and reperfusion. OBJECTIVE： To observe change...BACKGROUND： The p25-activated cyclin-dependent protein kinase 5 （Cdk5） may induce neuronal cell death and cause the development of dementia following cerebral ischemia and reperfusion. OBJECTIVE： To observe changes in the expression of Cdk5 and p25 in hippocampal tissue of vascular dementia mice at different time points following cerebral ischemia and reperfusion. DESIGN, TIME AND SETTING： A randomized, controlled animal experiment was performed in the clinical trial center of Hebei Provincial People＇s Hospital between September 2007 and October 2008. MATERIALS： Cdk5 rabbit anti-mouse polyclonal antibody, p35 rabbit anti-mouse polyclonal antibody, and β-actin mouse monoclonal antibody were purchased from Santa Cruz Biotechnology, Inc., USA; horseradish peroxidase-labeled goat anti-rabbit IgG and horseradish peroxidase-labeled goat anti-mice IgG were offered by Beijing Zhongshan Geldenbridye Biotechnology Co.,Ltd., China; the protein quantitative kit was produced by Applygen Gene Technology Corp., Beijing, China; cDNA reverse transcription and PCR amplification reagents were products of TianGen＆ Biotech （Beijing） Co.,Ltd., China. METHODS： One hundred and sixty male Kunming mice were randomly divided into two groups： a sham-operated group （n = 65） and a model group （n = 95）. Vascular dementia was induced with three periods of transient ischemia and reperfusion of the bilateral common carotid arteries. In the sham-operated group, the bilateral common carotid arteries were not blocked. MAIN OUTCOME MEASURES： Behavioral tests were done at four and six weeks post surgery. Pathological changes in the hippocampal CA1 region were observed with hematoxylin-eosin staining Cdk5 mRNA expression was examined by RT-PCR, and Western blots were used to evaluate Cdk5 and p25 expression. Learning and memory performance were assayed using the Morris water maze. RESULTS： Vascular dementia reduced learning and memory performance at 4 and 6 weeks post surgery. Vascular dementia also caused severe, time-dependent neuronal damage and death in the hippocampal CA1 region. Dementia induction also increased mRNA and protein expression of Cdk5 and p25 at both 4 and 6 weeks after surgery. CONCLUSION： Cdk5/p25 is involved in the development of vascular dementia in mice following cerebral ischemia and reperfusion.展开更多
AIM: To identify whether Aspergillus fumigatus(A.fumigatus) hyphae antigens induced the release of interleukin-8(IL-8) in anti-fungal innate immunity of cultured human corneal epithelial cells(HCECs) and determine the...AIM: To identify whether Aspergillus fumigatus(A.fumigatus) hyphae antigens induced the release of interleukin-8(IL-8) in anti-fungal innate immunity of cultured human corneal epithelial cells(HCECs) and determine the involvement of intracellular signalling pathways. METHODS: HCECs were treated with A. fumigatus hyphae antigens with different concentrations and time.The cytoplasmic calcium of HCECs were assessed by fluorescence imaging. Western blot was used to detect the expression of Ca2 +-dependent protein kinase C(PKC). The IL-8 levels were determined by specific human IL-8 enzyme-linked immunosorbent assay(ELISA) and reverse transcriptase polymerase chain reaction(RT-PCR). Using a series of pharmacological inhibitors, we examined the upstream signalling pathway responsible for IL-8 expression in response to A.fumigatus hyphae antigens. RESULTS: Cells exposed to A. fumigatus hyphae antigens showed higher level of IL-8 m RNA expression and protein production. We demonstrated here that stimulation of HCECs with A. fumigatus hyphae triggers an intracellular Ca2 +flux and results in the activation of Ca2 +-dependent PKC(α, βⅠ and βⅡ) which can be attenuated by pre-treatment of cells with laminarin,suggesting that Dectin-1 signals pathway induced cytoplasmic calcium and influence the activation of PKC in HCECs. Inhibitors of Ca2 +-dependent PKC(Ro-31-8220 and Go6976) significantly abolished hyphae-induced expression of IL-8.CONCLUSION: Our findings suggest that A. fumigatushyphae-induced IL-8 expression was regulated by the activation of Dectin-1-mediated Ca2 +-dependent PKC in HCECs.展开更多
In mammals,microRNAs(miRNAs)play key roles in multiple biological processes by regulating the expression of target genes.Studies have found that the levels of miR-370-5p expression differ significantly in the skins of...In mammals,microRNAs(miRNAs)play key roles in multiple biological processes by regulating the expression of target genes.Studies have found that the levels of miR-370-5p expression differ significantly in the skins of sheep with different hair colors;however,its function remains unclear.In this study,we investigated the roles of miR-370-5p in sheep melanocytes and found that the overexpression of miR-370-5p significantly inhibited cell proliferation(P<0.01),tyrosinase activity(P=0.001)and significantly reduced(P<0.001)melanin production.Functional prediction revealed that the 3′-untranslated region(UTR)of MAP3K8 has a putative miR-370-5p binding site,and the interaction between these two molecules was confirmed using luciferase reporter assays.In situ hybridization assays revealed that MAP3K8 is expressed in the cytoplasm of melanocytes.The results of quantitative RT-PCR and Western blotting analyses revealed that overexpression of miR-370-5p in melanocytes significantly inhibits(P<0.01)MAP3K8 expression via direct targeting of its 3′UTR.Inhibition of MAP3K8 expression by siRNA-MAP3K8 transfection induced a significant inhibition(P<0.01)of melanocyte proliferation and significant reduction(P<0.001)in melanin production,which is consistent with our observations for miR-370-5p.Target gene rescue experiments indicated that the expression of MAP3K8 in melanocytes co-transfected with miR-370-5p and MAP3K8-cDNA(containing sites for the targeted binding to miR-370-5p)was significantly rescued(P≤0.001),which subsequently promoted significant increases in cell proliferation(P<0.001)and melanin production(P<0.01).Collectively,these findings indicate that miR-370-5p plays a functional role in inhibiting sheep melanocyte proliferation and melanogenesis by downregulating the expression of MAP3K8.展开更多
Objective Proprionibacterium acnes(P.acnes)-induced inflammatory responses,proliferation and differentiation of keratinocytes contribute to the progression of acne vulgaris(AV).P.acnes was found to enhance the product...Objective Proprionibacterium acnes(P.acnes)-induced inflammatory responses,proliferation and differentiation of keratinocytes contribute to the progression of acne vulgaris(AV).P.acnes was found to enhance the production of interleukin-8(IL-8)by keratinocytes.This study aimed to investigate the role of IL-8 in P.acnes-induced proliferation and differentiation of keratinocytes and the underlying mechanism.Methods The P.acnes-stimulated HaCaT cell(a human keratinocyte cell line)model was established.Western blotting and immunofluorescence were performed to detect the expression of the IL-8 receptors C-X-C motif chemokine receptor 1(CXCR1)and C-X-C motif chemokine receptor 2(CXCR2)on HaCaT cells.Cell counting kit-8(CCK-8)assay,5-ethynyl-20-deoxyuridine(EdU)assay and Western blotting were performed to examine the effects of IL-8/CXCR2 axis on the proliferation and differentiation of HaCaT cells treated with P.acnes,the IL-8 neutralizing antibody,the CXCR2 antagonist(SB225002),or the CXCR1/CXCR2 antagonist(G31P).Western blotting,nuclear and cytoplasmic separation,CCK-8 assay,and EdU assay were employed to determine the downstream pathway of CXCR2 after P.acnes-stimulated HaCaT cells were treated with the CXCR2 antagonist,the protein kinase B(AKT)antagonist(AZD5363),or the constitutively active forkhead box O1(FOXO1)mutant.Finally,autophagy markers were measured in HaCaT cells following the transfection of the FOXO1 mutant or treatment with the autophagy inhibitor 3-methyladenine(3-MA).Results The expression levels of CXCR1 and CXCR2 were significantly increased on the membrane of HaCaT cells following P.acnes stimulation.The IL-8/CXCR2 axis predominantly promoted the proliferation and differentiation of P.acnes-induced HaCaT cells by activating AKT/FOXO1/autophagy signaling.In brief,IL-8 bound to its receptor CXCR2 on the membrane of keratinocytes to activate the AKT/FOXO1 axis.Subsequently,phosphorylated FOXO1 facilitated autophagy to promote the proliferation and differentiation of P.acnes-induced keratinocytes.Conclusion This study demonstrated the novel autocrine effect of IL-8 on the proliferation and differentiation of P.acnes-induced keratinocytes,suggesting a potential therapeutic target for AV.展开更多
目的探讨p38丝裂原活化蛋白激酶(p38 MAPK)对髓样相关蛋白8(MRP8)/髓样相关蛋白14(MRP14)诱导小鼠胚胎成纤维细胞凋亡的影响。方法制备MRP8、MRP14、MRP8/14备用。分别取p38^(+/+)和p38-/-细胞,随机分为空白对照组、MRP8组、MRP14组、MR...目的探讨p38丝裂原活化蛋白激酶(p38 MAPK)对髓样相关蛋白8(MRP8)/髓样相关蛋白14(MRP14)诱导小鼠胚胎成纤维细胞凋亡的影响。方法制备MRP8、MRP14、MRP8/14备用。分别取p38^(+/+)和p38-/-细胞,随机分为空白对照组、MRP8组、MRP14组、MRP8/14组。MRP8组、MRP14组、MRP8/14组分别加入50μg/m L MRP8、MRP14和MRP8/14。空白对照组加入等体积的DMEM培养液。各组干预24、48 h,采用MTT法检测p38^(+/+)和p38-/-细胞活力。采用流式细胞术检测空白对照组及MRP8/14干预24、48 h组p38^(+/+)和p38-/-细胞凋亡率。采用MTT法检测空白对照组、MRP8/14组以及TLR4受体抑制剂TAK242或RAGE中和抗体处理的MRP8/14(分别设为MRP8/14+TAK242组、MRP8/14+RAGE组)干预24 h p38^(+/+)细胞活力。采用MTT法和流式细胞术检测空白对照组、MRP8/14组以及p38激酶抑制剂SB203580处理的MRP8/14(设为MRP8/14+SB203580组)干预24 h p38^(+/+)细胞活力和凋亡率。采用Western blotting法检测MRP8/14干预0、1、2、4、6、8 h p38^(+/+)细胞p38 MAPK磷酸化。结果 MRP8组、MRP14组、MRP8/14组干预24、48 h p38^(+/+)、p38-/-细胞活力均低于空白对照组(P均<0.05),但无论MRP8/14组干预24 h还是48 h,p38-/-细胞活力明显高于p38^(+/+)细胞(P均<0.05)。MRP8/14干预24、48 h组p38^(+/+)细胞凋亡率均高于空白对照组,且MRP8/14干预48 h组细胞凋亡率更高(P均<0.05);而MRP8/14干预24、48 h组p38-/-细胞凋亡率均未见明显变化(P均>0.05)。MRP8/14组、MRP8/14+RAGE组干预24 h p38^(+/+)细胞活力低于空白对照组、MRP8/14+TAK242组干预24 h(P均<0.05)。MRP8/14+SB203580组干预24 h p38^(+/+)细胞活力较MRP8/14组干预24 h明显升高,细胞凋亡率较MRP8/14组干预24 h明显降低(P均<0.05)。MRP8/14干预2、4、6 h p38^(+/+)细胞p38 MAPK磷酸化水平明显高于干预0、1、8 h(P均<0.05)。结论 p38 MAPK能促进MRP8/14诱导的小鼠成纤维细胞凋亡,其机制可能与TLR4-p38 MAPK信号通路激活有关。展开更多
文摘BACKGROUND： The p25-activated cyclin-dependent protein kinase 5 （Cdk5） may induce neuronal cell death and cause the development of dementia following cerebral ischemia and reperfusion. OBJECTIVE： To observe changes in the expression of Cdk5 and p25 in hippocampal tissue of vascular dementia mice at different time points following cerebral ischemia and reperfusion. DESIGN, TIME AND SETTING： A randomized, controlled animal experiment was performed in the clinical trial center of Hebei Provincial People＇s Hospital between September 2007 and October 2008. MATERIALS： Cdk5 rabbit anti-mouse polyclonal antibody, p35 rabbit anti-mouse polyclonal antibody, and β-actin mouse monoclonal antibody were purchased from Santa Cruz Biotechnology, Inc., USA; horseradish peroxidase-labeled goat anti-rabbit IgG and horseradish peroxidase-labeled goat anti-mice IgG were offered by Beijing Zhongshan Geldenbridye Biotechnology Co.,Ltd., China; the protein quantitative kit was produced by Applygen Gene Technology Corp., Beijing, China; cDNA reverse transcription and PCR amplification reagents were products of TianGen＆ Biotech （Beijing） Co.,Ltd., China. METHODS： One hundred and sixty male Kunming mice were randomly divided into two groups： a sham-operated group （n = 65） and a model group （n = 95）. Vascular dementia was induced with three periods of transient ischemia and reperfusion of the bilateral common carotid arteries. In the sham-operated group, the bilateral common carotid arteries were not blocked. MAIN OUTCOME MEASURES： Behavioral tests were done at four and six weeks post surgery. Pathological changes in the hippocampal CA1 region were observed with hematoxylin-eosin staining Cdk5 mRNA expression was examined by RT-PCR, and Western blots were used to evaluate Cdk5 and p25 expression. Learning and memory performance were assayed using the Morris water maze. RESULTS： Vascular dementia reduced learning and memory performance at 4 and 6 weeks post surgery. Vascular dementia also caused severe, time-dependent neuronal damage and death in the hippocampal CA1 region. Dementia induction also increased mRNA and protein expression of Cdk5 and p25 at both 4 and 6 weeks after surgery. CONCLUSION： Cdk5/p25 is involved in the development of vascular dementia in mice following cerebral ischemia and reperfusion.
基金Supported by National Natural Science Foundation of China (No. 81470609 No. 81170825)+2 种基金the Specialized Research Fund for the Doctoral Program of Higher Education (No. 20123706110003)the Key Project of Natural Science Foundation of Shandong Province (No. ZR2012FZ001) the Youth Project of Natural Science Foundation of Shandong Province (No. ZR2013HQ007)
文摘AIM: To identify whether Aspergillus fumigatus(A.fumigatus) hyphae antigens induced the release of interleukin-8(IL-8) in anti-fungal innate immunity of cultured human corneal epithelial cells(HCECs) and determine the involvement of intracellular signalling pathways. METHODS: HCECs were treated with A. fumigatus hyphae antigens with different concentrations and time.The cytoplasmic calcium of HCECs were assessed by fluorescence imaging. Western blot was used to detect the expression of Ca2 +-dependent protein kinase C(PKC). The IL-8 levels were determined by specific human IL-8 enzyme-linked immunosorbent assay(ELISA) and reverse transcriptase polymerase chain reaction(RT-PCR). Using a series of pharmacological inhibitors, we examined the upstream signalling pathway responsible for IL-8 expression in response to A.fumigatus hyphae antigens. RESULTS: Cells exposed to A. fumigatus hyphae antigens showed higher level of IL-8 m RNA expression and protein production. We demonstrated here that stimulation of HCECs with A. fumigatus hyphae triggers an intracellular Ca2 +flux and results in the activation of Ca2 +-dependent PKC(α, βⅠ and βⅡ) which can be attenuated by pre-treatment of cells with laminarin,suggesting that Dectin-1 signals pathway induced cytoplasmic calcium and influence the activation of PKC in HCECs. Inhibitors of Ca2 +-dependent PKC(Ro-31-8220 and Go6976) significantly abolished hyphae-induced expression of IL-8.CONCLUSION: Our findings suggest that A. fumigatushyphae-induced IL-8 expression was regulated by the activation of Dectin-1-mediated Ca2 +-dependent PKC in HCECs.
基金funded by the Natural Science Foundation of Anhui Province,China(2008085QC158)the University Natural Science Research Project of Anhui Province(KJ2019A0165)。
文摘In mammals,microRNAs(miRNAs)play key roles in multiple biological processes by regulating the expression of target genes.Studies have found that the levels of miR-370-5p expression differ significantly in the skins of sheep with different hair colors;however,its function remains unclear.In this study,we investigated the roles of miR-370-5p in sheep melanocytes and found that the overexpression of miR-370-5p significantly inhibited cell proliferation(P<0.01),tyrosinase activity(P=0.001)and significantly reduced(P<0.001)melanin production.Functional prediction revealed that the 3′-untranslated region(UTR)of MAP3K8 has a putative miR-370-5p binding site,and the interaction between these two molecules was confirmed using luciferase reporter assays.In situ hybridization assays revealed that MAP3K8 is expressed in the cytoplasm of melanocytes.The results of quantitative RT-PCR and Western blotting analyses revealed that overexpression of miR-370-5p in melanocytes significantly inhibits(P<0.01)MAP3K8 expression via direct targeting of its 3′UTR.Inhibition of MAP3K8 expression by siRNA-MAP3K8 transfection induced a significant inhibition(P<0.01)of melanocyte proliferation and significant reduction(P<0.001)in melanin production,which is consistent with our observations for miR-370-5p.Target gene rescue experiments indicated that the expression of MAP3K8 in melanocytes co-transfected with miR-370-5p and MAP3K8-cDNA(containing sites for the targeted binding to miR-370-5p)was significantly rescued(P≤0.001),which subsequently promoted significant increases in cell proliferation(P<0.001)and melanin production(P<0.01).Collectively,these findings indicate that miR-370-5p plays a functional role in inhibiting sheep melanocyte proliferation and melanogenesis by downregulating the expression of MAP3K8.
基金supported by the National Natural Science Foundation of China(No.82103756).
文摘Objective Proprionibacterium acnes(P.acnes)-induced inflammatory responses,proliferation and differentiation of keratinocytes contribute to the progression of acne vulgaris(AV).P.acnes was found to enhance the production of interleukin-8(IL-8)by keratinocytes.This study aimed to investigate the role of IL-8 in P.acnes-induced proliferation and differentiation of keratinocytes and the underlying mechanism.Methods The P.acnes-stimulated HaCaT cell(a human keratinocyte cell line)model was established.Western blotting and immunofluorescence were performed to detect the expression of the IL-8 receptors C-X-C motif chemokine receptor 1(CXCR1)and C-X-C motif chemokine receptor 2(CXCR2)on HaCaT cells.Cell counting kit-8(CCK-8)assay,5-ethynyl-20-deoxyuridine(EdU)assay and Western blotting were performed to examine the effects of IL-8/CXCR2 axis on the proliferation and differentiation of HaCaT cells treated with P.acnes,the IL-8 neutralizing antibody,the CXCR2 antagonist(SB225002),or the CXCR1/CXCR2 antagonist(G31P).Western blotting,nuclear and cytoplasmic separation,CCK-8 assay,and EdU assay were employed to determine the downstream pathway of CXCR2 after P.acnes-stimulated HaCaT cells were treated with the CXCR2 antagonist,the protein kinase B(AKT)antagonist(AZD5363),or the constitutively active forkhead box O1(FOXO1)mutant.Finally,autophagy markers were measured in HaCaT cells following the transfection of the FOXO1 mutant or treatment with the autophagy inhibitor 3-methyladenine(3-MA).Results The expression levels of CXCR1 and CXCR2 were significantly increased on the membrane of HaCaT cells following P.acnes stimulation.The IL-8/CXCR2 axis predominantly promoted the proliferation and differentiation of P.acnes-induced HaCaT cells by activating AKT/FOXO1/autophagy signaling.In brief,IL-8 bound to its receptor CXCR2 on the membrane of keratinocytes to activate the AKT/FOXO1 axis.Subsequently,phosphorylated FOXO1 facilitated autophagy to promote the proliferation and differentiation of P.acnes-induced keratinocytes.Conclusion This study demonstrated the novel autocrine effect of IL-8 on the proliferation and differentiation of P.acnes-induced keratinocytes,suggesting a potential therapeutic target for AV.
文摘目的探讨p38丝裂原活化蛋白激酶(p38 MAPK)对髓样相关蛋白8(MRP8)/髓样相关蛋白14(MRP14)诱导小鼠胚胎成纤维细胞凋亡的影响。方法制备MRP8、MRP14、MRP8/14备用。分别取p38^(+/+)和p38-/-细胞,随机分为空白对照组、MRP8组、MRP14组、MRP8/14组。MRP8组、MRP14组、MRP8/14组分别加入50μg/m L MRP8、MRP14和MRP8/14。空白对照组加入等体积的DMEM培养液。各组干预24、48 h,采用MTT法检测p38^(+/+)和p38-/-细胞活力。采用流式细胞术检测空白对照组及MRP8/14干预24、48 h组p38^(+/+)和p38-/-细胞凋亡率。采用MTT法检测空白对照组、MRP8/14组以及TLR4受体抑制剂TAK242或RAGE中和抗体处理的MRP8/14(分别设为MRP8/14+TAK242组、MRP8/14+RAGE组)干预24 h p38^(+/+)细胞活力。采用MTT法和流式细胞术检测空白对照组、MRP8/14组以及p38激酶抑制剂SB203580处理的MRP8/14(设为MRP8/14+SB203580组)干预24 h p38^(+/+)细胞活力和凋亡率。采用Western blotting法检测MRP8/14干预0、1、2、4、6、8 h p38^(+/+)细胞p38 MAPK磷酸化。结果 MRP8组、MRP14组、MRP8/14组干预24、48 h p38^(+/+)、p38-/-细胞活力均低于空白对照组(P均<0.05),但无论MRP8/14组干预24 h还是48 h,p38-/-细胞活力明显高于p38^(+/+)细胞(P均<0.05)。MRP8/14干预24、48 h组p38^(+/+)细胞凋亡率均高于空白对照组,且MRP8/14干预48 h组细胞凋亡率更高(P均<0.05);而MRP8/14干预24、48 h组p38-/-细胞凋亡率均未见明显变化(P均>0.05)。MRP8/14组、MRP8/14+RAGE组干预24 h p38^(+/+)细胞活力低于空白对照组、MRP8/14+TAK242组干预24 h(P均<0.05)。MRP8/14+SB203580组干预24 h p38^(+/+)细胞活力较MRP8/14组干预24 h明显升高,细胞凋亡率较MRP8/14组干预24 h明显降低(P均<0.05)。MRP8/14干预2、4、6 h p38^(+/+)细胞p38 MAPK磷酸化水平明显高于干预0、1、8 h(P均<0.05)。结论 p38 MAPK能促进MRP8/14诱导的小鼠成纤维细胞凋亡,其机制可能与TLR4-p38 MAPK信号通路激活有关。
