The means of survival of genomic dsRNA of reoviruses from dsRNA-triggered and Dicer-initiated RNAi pathway remains to be defined. The present study aimed to investigate the effect of Grass carp reovirus (GCRV) replica...The means of survival of genomic dsRNA of reoviruses from dsRNA-triggered and Dicer-initiated RNAi pathway remains to be defined. The present study aimed to investigate the effect of Grass carp reovirus (GCRV) replication on the RNAi pathway of grass carp kidney cells (CIK). The dsRNA-triggered RNAi pathway was demonstrated unimpaired in CIK cells through RNAi assay. GCRV-specific siRNA was generated in CIK cells transfected with purified GCRV genomic dsRNA in Northern blot analysis; while in GCRV-infected CIK cells, no GCRV-specific siRNA could be detected. Infection and transfection experiments further indicated that replication of GCRV correlated with the increased transcription level of the Dicer gene and functional inhibition of in vitro synthesized egfp-siRNA in silencing the EGFP reporter gene. These data demonstrated that although only the genomic dsRNA of GCRV was sensitive to the cellular RNAi pathway, unidentified RNAi suppressor protein(s) might contribute to the survival of the viral genome and efficient viral replication.展开更多
The innate immune response is triggered by a variety of pathogens, including viruses, and requires rapid induction of typeⅠ?interferons (IFN), such as IFNβ and IFNα. IFN induction occurs when specific pathogen moti...The innate immune response is triggered by a variety of pathogens, including viruses, and requires rapid induction of typeⅠ?interferons (IFN), such as IFNβ and IFNα. IFN induction occurs when specific pathogen motifs bind to specific cellular receptors. In non-professional immune, virally-infected cells, IFN induction is essentially initiated after the binding of dsRNA structures to TLR3 receptors or to intracytosolic RNA helicases, such as RIG-Ⅰ/MDA5. This leads to the recruitment of specific adaptors, such as TRIF for TLR3 and the mitochondrial-associated IPS-1/VISA/MAVS/CARDIF adapter protein for the RNA helicases, and the ultimate recruitment of kinases, such as MAPKs, the canonical IKK complex and the TBK1/IKKε kinases, which activate the transcription factors ATF-2/ c-jun, NF-κB and IRF3, respectively. The coordinated action of these transcription factors leads to induction of IFN and of pro-inflammatory cytokines and to the establishment of the innate immune response. HCV can cleave both the adapters TRIF and IPS-1/VISA/MAVS/ CARDIF through the action of its NS3/4A protease. This provokes abrogation of the induction of the IFN and cytokine pathways and favours viral propagation and presumably HCV chronic infection.展开更多
Objective To assess the effects of Yi Qi Jie Du Decoction(YQJDD)on nasopharyngeal carcinoma stem cells(NPC-SCs)and investigate the underlying mechanism.Methods NPC-SCs were collected in serum-free culture system and i...Objective To assess the effects of Yi Qi Jie Du Decoction(YQJDD)on nasopharyngeal carcinoma stem cells(NPC-SCs)and investigate the underlying mechanism.Methods NPC-SCs were collected in serum-free culture system and identified by the sphere formation assay.The effect of YQJDD on the proliferation of NPC-SCs was detected using the Cell Counting Kit-8 assay.The change of mitochondrial membrane potential(ΔΨm)in NPC-SCs following treatment with YQJDD was investigated by JC-1 staining.The levels of apoptosisassociated proteins were examined using western blot analysis.Results YQJDD significantly inhibited the proliferation of NPCSCs in dose-and time-dependent manners.JC-1 staining revealed that YQJDD lowered theΔΨm of NPC-SCs in a timedependent manner.After treatment with YQJDD,the expression of cleaved caspase-3,-7 and-9,cleaved poly-ADP ribose polymerase,P21 and P53 were increased,while the expression of Survivin in NPC-SCs was decreased.However,the expression of cleaved caspase-8 remained nearly unchanged.Conclusions YQJDD inhibits the growth and induces apoptosis of NPC-SCs via an intrinsic apoptosis pathway.展开更多
OBJECTIVE: Inactivation of the Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3) signaling axis plays a crucial role in determining the fate of neural stem cells(NSCs).Qingnaoyizhi decocti...OBJECTIVE: Inactivation of the Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3) signaling axis plays a crucial role in determining the fate of neural stem cells(NSCs).Qingnaoyizhi decoction(QNYZD) has been used for the treatment of vascular dementia and has shown to improve synaptic remodeling. The aim of this study was to evaluate the effect of cerebrospinal fluid(CSF) containing QNYZD(CSF-QNYZD) on the differentiation of cultured NSCs and the involvement of the JAK2/STAT3 pathway.METHODS: The protein expression levels of glial fibrillary acidic protein(GFAP), tubulin, drosophila mothers against decapentaplegic protein(SMAD-1), STAT3, and phosphorylated-STAT3 were detected by western immunoblot analysis in the groups: control, CSF, JAK/STAT inhibitor(AG490),CSF-QNYZD, and CSF-XDZ(CSF-Xidezhen). The differentiation of NSCs was determined by immunofluorescence staining. The proliferation of NSCs was measured using the Cell Counting Kit-8 proliferation assay.RESULTS: Compared with the control group,CSF-QNYZD and AG490 significantly increased the number and expression of tubulin-positive cells, reduced the number and expression of GFAP-positive cells, and down-regulated the expression of p-STAT3. However, CSF-QNYZD also decreased the expression of SMAD-1 and STAT3.CONCLUSION: Enhanced neuronal differentiation may be associated with the down-regulation of glial differentiation instead of promoting proliferationin treated NSCs. Furthermore, QNYZD may play a direct role in suppressing the formation of GFAP-positive cells and enhancing neuronal differentiation by inhibiting JAK2/STAT3 activation. Overall, these results provide insights into the possible mechanism underlying QNYZD-mediated neurogenesis.展开更多
Signaling pathways transduce extracellular stimuli into cells through molecular cascades to regulate cellular functions.In stem cells,a small number of pathways,notably those of TGF-?/BMP,Hedgehog,Notch,and Wnt,are re...Signaling pathways transduce extracellular stimuli into cells through molecular cascades to regulate cellular functions.In stem cells,a small number of pathways,notably those of TGF-?/BMP,Hedgehog,Notch,and Wnt,are responsible for the regulation of pluripotency and differentiation.During embryonic development,these pathways govern cell fate specifications as well as the formation of tissues and organs.In adulthood,their normal functions are important for tissue homeostasis and regeneration,whereas aberrations result in diseases,such as cancer and degenerative disorders.In complex biological systems,stem cell signaling pathways work in concert as a network and exhibit crosstalk,such as the negative crosstalk between Wnt and Notch.Over the past decade,genetic and genomic studies have identified a number of potential drug targets that are involved in stem cell signaling pathways.Indeed,discovery of new targets and drugs for these pathways has become one of the most active areas in both the research community and pharmaceutical industry.Remarkable progress has been made and several promising drug candidates have entered into clinical trials.This review focuses on recent advances in the discovery of novel drugs which target the Notch and Wnt pathways.展开更多
Osteoarthritis(OA)is one of the most prevalent joint diseases with prominent symptoms affecting the daily life of millions of middle aged and elderly people.Despite this,there are no successful medical interventions t...Osteoarthritis(OA)is one of the most prevalent joint diseases with prominent symptoms affecting the daily life of millions of middle aged and elderly people.Despite this,there are no successful medical interventions that can prevent the progressive destruction of OA joints.The onset of pathological changes in OA is associated with deviant activity of mesenchymal stem cells(MSCs),the multipotent precursors of connective tissue cells that reside in joints.Current therapies for OA have resulted in poor clinical outcomes without repairing the damaged cartilage.Intra-articular delivery of culture-expanded MSCs has opened new avenues of OA treatment.Pre-clinical and clinical trials demonstrated the feasibility,safety,and efficacy of MSC therapy.The Wnt/β-catenin,bone morphogenetic protein 2,Indian hedgehog,and Mitogen-activated protein kinase signaling pathways have been demonstrated to be involved in OA and the mechanism of action of MSC therapies.展开更多
基金The Shanghai committee of Science and Technology(Grant No.10PJ1404800)the National Natural Science Foundation of China(Grant No.31072244)
文摘The means of survival of genomic dsRNA of reoviruses from dsRNA-triggered and Dicer-initiated RNAi pathway remains to be defined. The present study aimed to investigate the effect of Grass carp reovirus (GCRV) replication on the RNAi pathway of grass carp kidney cells (CIK). The dsRNA-triggered RNAi pathway was demonstrated unimpaired in CIK cells through RNAi assay. GCRV-specific siRNA was generated in CIK cells transfected with purified GCRV genomic dsRNA in Northern blot analysis; while in GCRV-infected CIK cells, no GCRV-specific siRNA could be detected. Infection and transfection experiments further indicated that replication of GCRV correlated with the increased transcription level of the Dicer gene and functional inhibition of in vitro synthesized egfp-siRNA in silencing the EGFP reporter gene. These data demonstrated that although only the genomic dsRNA of GCRV was sensitive to the cellular RNAi pathway, unidentified RNAi suppressor protein(s) might contribute to the survival of the viral genome and efficient viral replication.
基金grants from the Agence Nationale pour la Recherche contre le SIDA
文摘The innate immune response is triggered by a variety of pathogens, including viruses, and requires rapid induction of typeⅠ?interferons (IFN), such as IFNβ and IFNα. IFN induction occurs when specific pathogen motifs bind to specific cellular receptors. In non-professional immune, virally-infected cells, IFN induction is essentially initiated after the binding of dsRNA structures to TLR3 receptors or to intracytosolic RNA helicases, such as RIG-Ⅰ/MDA5. This leads to the recruitment of specific adaptors, such as TRIF for TLR3 and the mitochondrial-associated IPS-1/VISA/MAVS/CARDIF adapter protein for the RNA helicases, and the ultimate recruitment of kinases, such as MAPKs, the canonical IKK complex and the TBK1/IKKε kinases, which activate the transcription factors ATF-2/ c-jun, NF-κB and IRF3, respectively. The coordinated action of these transcription factors leads to induction of IFN and of pro-inflammatory cytokines and to the establishment of the innate immune response. HCV can cleave both the adapters TRIF and IPS-1/VISA/MAVS/ CARDIF through the action of its NS3/4A protease. This provokes abrogation of the induction of the IFN and cytokine pathways and favours viral propagation and presumably HCV chronic infection.
基金funding support from the National Natural Science Foundation of China (No. 81573721, No. 81874408 and No. 81973914)the Natural Science Foundation of Hunan (No. 2017JJ3246 and No. 2019JJ40216)Excellent Youth Fund of Hunan Provincial Education Department (No. 19B439)
文摘Objective To assess the effects of Yi Qi Jie Du Decoction(YQJDD)on nasopharyngeal carcinoma stem cells(NPC-SCs)and investigate the underlying mechanism.Methods NPC-SCs were collected in serum-free culture system and identified by the sphere formation assay.The effect of YQJDD on the proliferation of NPC-SCs was detected using the Cell Counting Kit-8 assay.The change of mitochondrial membrane potential(ΔΨm)in NPC-SCs following treatment with YQJDD was investigated by JC-1 staining.The levels of apoptosisassociated proteins were examined using western blot analysis.Results YQJDD significantly inhibited the proliferation of NPCSCs in dose-and time-dependent manners.JC-1 staining revealed that YQJDD lowered theΔΨm of NPC-SCs in a timedependent manner.After treatment with YQJDD,the expression of cleaved caspase-3,-7 and-9,cleaved poly-ADP ribose polymerase,P21 and P53 were increased,while the expression of Survivin in NPC-SCs was decreased.However,the expression of cleaved caspase-8 remained nearly unchanged.Conclusions YQJDD inhibits the growth and induces apoptosis of NPC-SCs via an intrinsic apoptosis pathway.
基金Supported by 973 Project for Basic Research of Traditional Chinese Medicine(No.2010CB530405)the National Natural Science Foundation of China(Effects and Mechanisms of Storax on NF-ΚB-Mediated Inflammatory Response During Cerebral Ischemia-Reperfusion Injure,No.81273815)+1 种基金the Foundation for the Author of National Excellent Doctoral Dissertation of China(No.201082)the China Postdoctoral Fund of Sciences(The Effect of Cerebrospinal Fluid Containing Yishenhuazhuo Decotion on the Self-Renewal and Differentiation of Neural Stem Cell,No.2012M520587)
文摘OBJECTIVE: Inactivation of the Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3) signaling axis plays a crucial role in determining the fate of neural stem cells(NSCs).Qingnaoyizhi decoction(QNYZD) has been used for the treatment of vascular dementia and has shown to improve synaptic remodeling. The aim of this study was to evaluate the effect of cerebrospinal fluid(CSF) containing QNYZD(CSF-QNYZD) on the differentiation of cultured NSCs and the involvement of the JAK2/STAT3 pathway.METHODS: The protein expression levels of glial fibrillary acidic protein(GFAP), tubulin, drosophila mothers against decapentaplegic protein(SMAD-1), STAT3, and phosphorylated-STAT3 were detected by western immunoblot analysis in the groups: control, CSF, JAK/STAT inhibitor(AG490),CSF-QNYZD, and CSF-XDZ(CSF-Xidezhen). The differentiation of NSCs was determined by immunofluorescence staining. The proliferation of NSCs was measured using the Cell Counting Kit-8 proliferation assay.RESULTS: Compared with the control group,CSF-QNYZD and AG490 significantly increased the number and expression of tubulin-positive cells, reduced the number and expression of GFAP-positive cells, and down-regulated the expression of p-STAT3. However, CSF-QNYZD also decreased the expression of SMAD-1 and STAT3.CONCLUSION: Enhanced neuronal differentiation may be associated with the down-regulation of glial differentiation instead of promoting proliferationin treated NSCs. Furthermore, QNYZD may play a direct role in suppressing the formation of GFAP-positive cells and enhancing neuronal differentiation by inhibiting JAK2/STAT3 activation. Overall, these results provide insights into the possible mechanism underlying QNYZD-mediated neurogenesis.
文摘Signaling pathways transduce extracellular stimuli into cells through molecular cascades to regulate cellular functions.In stem cells,a small number of pathways,notably those of TGF-?/BMP,Hedgehog,Notch,and Wnt,are responsible for the regulation of pluripotency and differentiation.During embryonic development,these pathways govern cell fate specifications as well as the formation of tissues and organs.In adulthood,their normal functions are important for tissue homeostasis and regeneration,whereas aberrations result in diseases,such as cancer and degenerative disorders.In complex biological systems,stem cell signaling pathways work in concert as a network and exhibit crosstalk,such as the negative crosstalk between Wnt and Notch.Over the past decade,genetic and genomic studies have identified a number of potential drug targets that are involved in stem cell signaling pathways.Indeed,discovery of new targets and drugs for these pathways has become one of the most active areas in both the research community and pharmaceutical industry.Remarkable progress has been made and several promising drug candidates have entered into clinical trials.This review focuses on recent advances in the discovery of novel drugs which target the Notch and Wnt pathways.
文摘Osteoarthritis(OA)is one of the most prevalent joint diseases with prominent symptoms affecting the daily life of millions of middle aged and elderly people.Despite this,there are no successful medical interventions that can prevent the progressive destruction of OA joints.The onset of pathological changes in OA is associated with deviant activity of mesenchymal stem cells(MSCs),the multipotent precursors of connective tissue cells that reside in joints.Current therapies for OA have resulted in poor clinical outcomes without repairing the damaged cartilage.Intra-articular delivery of culture-expanded MSCs has opened new avenues of OA treatment.Pre-clinical and clinical trials demonstrated the feasibility,safety,and efficacy of MSC therapy.The Wnt/β-catenin,bone morphogenetic protein 2,Indian hedgehog,and Mitogen-activated protein kinase signaling pathways have been demonstrated to be involved in OA and the mechanism of action of MSC therapies.
