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RESUMEN La quinasa dependiente de ciclina 5 (CDK5) regula diversas funciones en neuronas, células endoteliales y epiteliales, entre ellas la dinámica del citoesqueleto. Así mismo, se ha reportado que componentes del citoesqueleto, tales como, filamentos de actina y microtúbulos juegan un rol importante durante la infección por el virus dengue (DENV). El objetivo del presente trabajo fue evaluar por dos métodos, inhibición química y silenciamiento génico, la participación de CDK5 durante la infección por DENV-2. La actividad antiviral de roscovitina fue evaluada usando ensayos de Unidades Formadoras de Placa (PFU). La eficiencia de transfección y el silenciamiento de CDK5, empleando miARNs artificiales, se determinó por citometría de flujo. El efecto sobre la proteína de envoltura viral y elementos del citoesqueleto se evidenció mediante microscopia avanzada de fluorescencia y análisis de imágenes. Roscovitina mostró actividad antiviral en etapas pre y post-infectivas en una forma dependiente de la dosis. El tratamiento con roscovitina y miRCDK5 mostró ser efectivo reduciendo la cantidad de CDK5 en células no infectadas. En células infectadas y transfectadas con miRCDK5, así como tratadas con el inhibidor, se observó una reducción significativa de la proteína de envoltura viral; sin embargo, no se encontró reducción significativa de CDK5. Además, el tratamiento con roscovitina indujo cambios celulares morfológicos evidentes en células infectadas. Los resultados indican la potencial participación de CDK5 durante la infección por DENV-2, posiblemente mediando la traducción proteica o la replicación del genoma viral a través de la regulación de la dinámica del citoesqueleto. Se requieren datos adicionales para esclarecer la mecanística del fenómeno usando métodos alternativos.
ABSTRACT Cyclin-Dependent Kinase 5 (CDK5) regulates several functions in neurons, endothelial, and epithelial cells, including the cytoskeleton dynamics. Likewise, it has been reported that some cytoskeleton elements, such as actin filaments and microtubules, play an essential role during Dengue virus (DENV) infection. This work aimed to evaluate the role of CDK5 during DENV-2 infection by two methods, chemical inhibition, and gene silencing. The antiviral activity of roscovitine was evaluated using Plaque Forming Units (PFU) assay. The transfection efficiency and knockdown of CDK5, using artificial miRNAs, was carried out by flow cytometry. The effect on the viral envelope protein and cytoskeleton elements was evidenced by advanced fluorescence microscopy and image analysis. Roscovitine showed antiviral activity in pre and post-infection stages in a dose-dependent manner. Treatment with roscovitine and miRCDK5 decrease the amount of CDK5 in uninfected cells. In cells infected and transfected with miRCDK5, as well as treated with the inhibitor, a significant reduction of the viral envelope protein was observed; however, no significant reduction of CDK5 was found. Also, evident morphological cellular changes were observed during the treatment with roscovitine in infected cells. The results indicate the potential participation of CDK5 during DENV-2 infection, possibly mediating protein translation or replication of the viral genome through the cytoskeletal dynamics regulation. Additional data are required to clarify the mechanistic of these phenomena using alternative methods.
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Aim: To observe the effect of roscovitine on TNF-α-induced proliferation and cell cycle of rat vascular smooth muscle cells (VSMCs). Methods: VSMCs were isolated and cultured using tissue explant method. Tumor necrosis factor-alpha (TNF-α) was used to induce the proliferation of VSMCs. VSMCs were divided into control group, TNF-α group and roscovitine 5, 10, 15, 30 μmol · L-1 group. Cell proliferation was detected with MTT, and PCNA expression was tested. Flow cytometry was used to detect the cell cycle. The expressions of cyclin proteins (Cyclin A, Cyclin B, Cyclin D, Cyclin E), cyclin-dependent kinase proteins(CDK4, CDK5), and cell cycle inhibitory proteins(p53, p21, p27) were examined by realtime reverse transcription PCR(qRT-PCR) and Western blot. Results: Roscovitine could inhibit the proliferation of VSMCs. Roscovitine inhibited transformation of cell cycle from G0/G1 phase to S phase. Compared with TNF-a group, the expressions of Cyclin A, Cyclin B, Cyclin D, Cyclin E protein decreased, the expressions of CDK4 and CDK5 protein decreased, while the expression of p53, p21 and p27 protein in cell cycle increased of roscovitine 5, 10, 15, 30 μmol · L-1 group (P < 0. 05). Conclusion: Roscovitine inhibits the cell cycle progression and proliferative activity of rat VSMCs.
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Background & objectives: The lower recovery of competent oocytes in buffalo species limits the commercialization of in vitro embryo production technology in field condition. In this context, pre-maturation of small follicle (SF)-derived oocytes with meiotic inhibition may be a promising alternative to obtain more number of competent oocytes. Thus, the present study was conducted with an objective to enhance the developmental potential of less competent SF-derived buffalo oocytes. Methods: All the visible follicles (used for aspiration) from buffalo ovaries were divided into two categories: large follicle (LF) (follicles having diameter ?6 mm) and SF (follicles of diameter <6 mm). The competence of LF and SF oocytes was observed in terms of brilliant cresyl blue (BCB) staining, cleavage rate, blastocyst rate and relative gene expression of oocyte and blastocyst competence markers. Thereafter, less competent SF oocytes were treated with 0, 12.5, 25, 50 and 100 mM doses of roscovitine (cyclin-dependent kinase inhibitor) to enhance their developmental potential. Results: Based on parameters studied, LF oocytes were found to be more competent than SF oocytes. Pre-maturation incubation of SF oocytes with roscovitine reversibly arrested oocyte maturation for 24 h to ensure the proper maturation of less competent oocytes. A significantly higher number of BCB-positive oocytes were noted in roscovitine-treated group than SF group. Cleavage and blastocyst rates were also higher in roscovitine-treated group. The relative messenger RNA expression of oocyte (GDF9, BMP15, GREM1, EGFR, PTGS2 and HAS2) as well as blastocyst (INF-?, GLUT1 and POU5F1) competence markers was significantly greater in roscovitine-treated group relative to SF group. Again, on comparison with LF group, these parameters depicted a lower value in the treatment group. Interpretation & conclusions: The findings of this study has revealed that pre-maturation incubation of SF-derived oocytes with 25 ?M roscovitine can improve its developmental competence and thus can be utilized to get maximum number of competent oocytes for better commercialization of in vitro embryo production technology in buffalo.
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Objective To investigate the mechanism of Roscovitine, an inhibitor of cyclin-dependent kinase (CDK), in inhibiting HBV replication.Methods Recombiant expression plasmids of SAMHD1 (sterile alpha motif and histidine/aspartic acid domain-containing protein 1) mutants that were defective in dNTPase (deoxynucleoside triphosphate triphosphohydrolase) activity and phosphorylation at the threonine (T) 592 residue were constructed.Huh7.0 cells were respectively co-transfected with different SAMHD1 mutants in combiantion with HBV replication plasmid to analyze whether the retroviral restriction ability of SAMHD1 was regulated by phosphorylation.The cytotoxicity of Roscovitine to Huh7 cells was evaluated by MTT assay.HBV core-associated DNA levels and phosphorylation of SAMHD1 in transfected Huh7.0 cells which were treated with different concentrations of Roscovitine were measured by Southern blot and Western blot assays.Results The SAMHD1 mutant that was defective in the dNTPase active site of D207N lost its ability to restrict HBV replication.Dephosphorylation of SAMHD1 at T592 enhanced its restriction on HBV.The median toxic concentration (TC50) of Roscovitine was 11.20 μmol/L.Both the HBV core-associated DNA levels and the phosphorylation of SAMHD1 were down-regulated by Roscovitine.Conclusion The anti-HBV function of SAMHD1 in dividing cells is regulated by phosphorylation.Roscovitine can inhibit the replication of HBV through reducing the phosphorylation of SAMHD1.
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AIM:To study the effect of roscovitine on the inflammatory hyperplasia of carotid artery intima in rats and the related mechanisms .METHODS: SD rats ( n=60 ) were randomly divided into 3 groups including control group, model group and treatment group .The rat model was established by trypsin digestion injury .The rats in control group were given sham operation .The rats in treatment group were administered with 0.5 mL roscovitine (2 g/L) slow-re-leasing gelatin.The rats in each group were fed normally for 4 weeks, then killed to take out carotid arteries for further ob-servations .The effects of roscovitine on the inflammatory hyperplasia of carotid artery intima and the related mechanism via nuclear factor-κB ( NF-κB) in the rats were detected by Western blot .RESUITS:Roscovitine inhibited the activation of NF-κB and the expression of inflammatory factors cyclooxygenase-2 (COX-2), vascular cell adhesion molecule-1 (VCAM-1),TNF-αand IL-6 via blocking the phosphorylation activation of NF-κB and inhibiting the degradation of IκB-α.CON-CLUSION:Roscovitine inhibits inflammatory hyperplasia of carotid artery intima in the rats via suppressing NF-κB activa-tion.
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Objective To observe the protective effects of roscovitine on the podocyte injury induced by endoplasmic reticulum stress (ERS) caused by tunicamycin. Methods The differentiated podocytes cultured at 37℃were randomly di-vided into:(1) Control group, DMSO group and tunicamycin group (TM, 1.0μmol/L). The treatment was given for 3, 6 and 12 hours in three groups. (2) For control group, tunicamycin group, tunicamycin+roscovitine group (20, 40μmol/L, TM+ROS), the treatment was given for 12 hours. The podocyte apoptosis was detected by flow cytometry and TUNEL method. The ex-pressions of Cdk5, GRP78, Caspase-12 and CHOP were detected by Western blot assay. Results (1) Compared with con-trol group and DMSO group, the podocyte apoptosis was increased significantly in a time dependent manner after tunicamy-cin treatment in TM group;the protein expressions of Cdk5, GRP78, Caspase-12 and CHOP were also up-regulated signifi-cantly in TM group (P<0.05). (2) Flow cytometry and TUNEL analysis showed that tunicamycin induced apoptosis in podo-cytes, which was significantly inhibited by roscovitine in a concentration dependent manner in TM+ROS group as compared to that of TM group (P<0.05). The protein expressions of GRP78, Caspase-12 and CHOP were also significantly decreased in a concentration dependent manner in TM+ROS group compared to those of TM group (P<0.05). Conclusion Roscovi-tine, the inhibitor of Cdk5, can reduce the podocyte apoptosis induced by tunicamycin. The protective effects of roscovitine on podocytes can be a novel approach of treating diabetic nephropathy.
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Background Study determined that retinitis pigmentosa has a similar pathogenesis mechanism to Alzheimer disease,and activity of cyclin-dependent kinase 5 (Cdk5) and its activators participates in the degeneration of central nervous system.Roscovitine,an inhibitor of Cdk5,can suppress activity of Cdk5/p25 pathway and therefore inhibit cell apoptosis.However,the influence of roscovitine on retinitis pigmentosa(RP) is unclear.Objective This study was to investigate the expressions of p35,p25 and tau in the retinas of RCS rats.Methods Roscovitine of 4 μl was intravitreally injected in the right eyes of 12 SPF 17-day-old RCS rats,and the fellow eyes were not intervened as the control eyes.The rats were sacrificed on eighth day (postnatal 25 days) and eighteenth day (postnatal 35 days),and whole retinas were isolated to evaluate the relative expressions of Cdk5,p35,p25 and tau phosphorylation by Western blot,and the activity of Cdk5/p25 was analyzed by quantitative colorimetric assay.The results were compared between the right eyes and fellow eyes by paired t test.The use and care of the rats complied with Ethic Statement of Experimental Animal of Ningxia Medical University.Results In the eighth and eighteenth day after injection,the relative expression values (A values) of p35 in rat retinas were 1.186±0.019 and 1.069± 0.019 in the injected eyes,showing significant decreases in comparison with 1.364±0.016 and 1.214±0.008 of the fellow eyes (t =-6.294,-6.477,both at P＜0.05);the relative expression values (A values) of p25 in rat retinas were 0.312±0.009 and 0.269±0.018 in the injected eyes,which was significantly lower than 0.595±0.013 and 0.473±0.011 of the fellow eyes (t=-36.508,-11.879,both at P＜0.05).No significant difference was found in the relative expression of Cdk5 protein between the injected eyes and the fellow eyes in various time points after injection (both at P＞0.05).The activities of Cdk5/p25 were (0.003 83 ±0.000 14) mol/(s · mg) and (0.002 01 ± 0.000 11) mol/(s · mg) in the injected eyes,with significant decreases in comparison with the (0.005 47±0.000 27)mol/(s · mg)and (0.003 35±0.000 15) mol/(s · mg) of the fellow eyes (t=-9.152,P=0.000;t=-9.248,P=0.000),and the tau phosphorylation levels followed the same pattern in the eighth and eighteenth day after injection (t =-9.854,-6.744,both at P＜0.05).Conclusions Intravitreal injection of roscovitine can inhibit the activity of Cdk5/p25 and tau phosphorylation level in retinas of RCS rats to certain extend.
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O objetivo deste estudo foi avaliar a maturação e o desenvolvimento embrionário após a fecundação in vitro de oócitos bovinos que tiveram a maturação bloqueada com Butirolactona I e Roscovitina em meio de pré-maturação suplementado com soro fetal bovino (SFB). Oócitos foram divididos em 4 grupos: Controle 0 hora, Controle (maturação por 24 horas), Butirolactona I (bloqueio da maturação com 150μM de Butirolactona I por 24 horas, seguido de 24 horas de maturação) e Roscovitina (bloqueio da maturação com 50μM de Roscovitina por 24 horas, seguido de 24 horas de maturação). Para avaliar a maturação nuclear, os oócitos foram fixados e corados em aceto orceína. Parte dos oócitos dos grupos Controle 24 horas, Roscovitina e Butirolactona I após o período de maturação, foi fecundado in vitro. O desenvolvimento embrionário foi avaliado pelos índices de clivagem (D3) e formação de blastocistos (D7). Oócitos do grupo Butirolactona I apresentaram índices de Vesícula Germinativa após o bloqueio e de Metáfase 2 após a maturação semelhantes ao dos grupos Controle 0 hora e Controle, respectivamente. Por outro lado, a Roscovitina apresentou menores índices de Vesícula Germinativa e Metáfase 2. Os grupos Controle e Butirolactona I apresentaram maiores índices de clivagens. O grupo Controle apresentou maior produção de blastocistos que o Roscovitina e não diferiu do grupo Butirolactona I. Conclui-se que a Butiroloactona I pode ser utilizada no sistema de pré-maturação em meio contendo SFB, pois apresentou resultados semelhantes ao do grupo Controle o mesmo não ocorrendo com a Roscovitina, que apresentou menores índices de maturação oocitária e de desenvolvimento embrionário.
This study evaluated the bovine oocyte maturation and embryo development after in vitro fertilization. The maturation of the oocytes was blocked using Butyrolactone I and Roscovitine using pre-maturation medium supplemented with fetal calf serum (FCS). The ocytes were divided in four groups: Control 0 hour, Control (24 hours of maturation), Roscovitine (maturation blockage with 50mM Roscovitine during 24 hours followed by 24 hours of maturation), and Butyrolactone I (maturation blockage with 150mM Butyrolactone I during 24 hours followed by 24 hours of maturation). The oocytes were fixed and stained with aceto orcein to evaluate the nuclear maturation. After the maturation period, the remaining oocytes of the Control group, Roscovitine, and Butyrolactone I were fertilized in vitro. Embryo development was assessed by the cleavage rate (D3) and blastocysts formation (D7). The Butyrolactone I group had similar rates of germinal vesical stage oocytes during blockage, and Metaphase 2 after maturation, comparing to Control group at 0 hour and Control group, respectively. On the other hand, the Roscovitine group had lower rates of vesical stage oocytes during blockage, and Metaphase 2 after maturation comparing to Control groups. After in vitro fertilization, higher rates of cleavage were observed in Control and Butyrolactone I groups. For the blastocyst formation rate, the Control group showed better results than Roscovitine group. In summary, Butyrolactone I group had similar results to the Control group, and for this reason, is suitable for pre-maturation of bovine oocytes using FCS. In contrast, Roscovitine group had lower oocyte maturation and embryo development.
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Animals , Cattle/classification , Embryonic Development , In Vitro Oocyte Maturation Techniques/methodsABSTRACT
Objective To establish a novel method to screen for anti-varicella-zoster virus (VZV) compounds with our previously generated reporter cell line for VZV, MV9G. MethodsMV9G cells were directly infected with cell-free virus of Oka vaccine strain (vOka) for 2 hours( CFV direct-infection) or cocultured with vOka-infected MeWo cells containing cell-associated virus for 48 hours (CAV co-culture) to promote expression of the reporter gene firefly luciferase. Antiviral compounds including heparin, mannose-6-phosphate( M-6-P), acyclovir( ACV ), resveratrol and roscovitine were added in the medium before or after the virus infection. Inhibitory effects( IC50 ) of the antiviral compounds were analyzed by comparing firefly luciferase activities of MV9G cells in the presence of antiviral compounds with those in the absence. Results Antiviral compounds inhibited luciferase activities of MV9G cells activated by CFV direct-infection and/or CAV co-culture in different levels. The reductions of luciferase activities statistically correlated with those of viral foci shown by immunostaining with a monoclonal antibody against VZV immediate early 62 antigens (IE62) in controls. Among these compounds, heparin, M-6-P, and 2.5 μmol/L of roscovitine inhibited CFV-activated more strongly than CAV-activated luciferase activities, whereas ACV and resveratrol inhibited CAV-activated more strongly than CFV-activated luciferase activities. Cell-associated ACV-resistant strains,Kanno and rOka YSR, activated luciferase activities of MV9G cells, too. However, the inhibitory concentrations (IC50) of ACV to the ACV-resistant strains were much higher than those to the ACV-sensitive strains,pOka and CaGu. ConclusionThe CFV direct-infection and CAV co-culture assays were useful to screen for antiviral compounds targeting the early and late phases of VZV infection, respectively. The VZV reporter cell-based assays may provide a simple, rapid, sensitive, and high-throughput method to screen for anti-VZV compounds.
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ObjectiveTo study the effects of intrathecal injection of cyclin dependent kinase 5 inhibitor Roscovitine on the hyperalgesia induced by remifentanil in a rat model of incisional pain.MethodsForty-five SD rats were randomly divided into 5 groups ( n =9 in each group):control group ( C ),incisional pain group ( Ⅰ ),Roscovitine group(ROS),remifentanil group(R) and Roscovitine + remifentanil group ( ROS + R).Roscovitine (50μg/10μl) was injected intrathecally at 30 min before plantar incision in groups ROS and ROS + R,other groups were injected with 20％ DMSO(10μl).All groups except for C group needed to be made the model of incisional pain.In group R and ROS + R,remifentanil(0.04 mg/kg) was infused subcutaneously with a pump for 30min at the moment of surgical incision.The paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency(PWTL) were used to evaluate the behavioral changes and measured at 24 h before incision and at 2 h,6 h,24 h and 48 h after incision.ResultsCompared with group C,the PWMT and PWTL of group Ⅰ were significantly decreased after incision (P＜0.01).Compared with group Ⅰ,the PWMT and PWTL of group R were significantly decreased after incision (P ＜ 0.01 ) ; however,the PWTL was significantly increased (2h:( 20.26 ± 1.33)s,(17.97 ±0.47)s;48h:(22.15 ±0.660)s,(19.89 ±1.27) s),P＜0.05)in ROS group.Compared with group R,at 2h after incision,the significant increase of PWTL ( ( 19.13 ± 1.72)s,( 14.41 ± 2.30) s) and PWMT ( ( 10.4 ± 1.95 ) g,(6.38 ± 0.91 ) g) were observed,then lasted up to 48 h ( ( 19.24 ± 2.8 ) s,( 14.87 ± 1.95 ) s )and 24h ( (8.88 ± 1.41 ) g,( 6.83 ± 0.80) g) respectively in group ROS + R (P ＜ 0.05 ).ConclusionIn a rat model of postoperative pain,Roseovitine could reduce the thermal hyperalgesia purely induced by incision,and also could prevent the development of hyperalgesia induced by remifentanil.
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Co-infection of herpes simplex virus type 1 (HSV-1) and human cytomegalovirus (HCMV) is not uncommon in immunocompromised hosts. Importantly, organ transplant recipients concurrently infected with HSV-1 and HCMV have a worse clinical outcome than recipients infected with a single virus. However, factors regulating the pathologic response in HSV-1, HCMV co-infected tissues are unclear. We investigated the potential biologic role of HCMV gene product immediate early 1 (IE1) protein in HSV-1-induced syncytial formation in U373MG cells. We utilized a co-infection model by infecting HSV-1 to U373MG cells constitutively expressing HCMV IE1 protein, UMG1-2. Syncytial formation was assessed by enumerating nuclei number per syncytium and number of syncytia. HSV-1-induced syncytial formation was enhanced after 24 hr in UMG1-2 cells compared with U373MG controls. The amplified phenotype in UMG1-2 cells was effectively suppressed by roscovitine in addition to inhibitors of viral replication. This is the first study to provide histological evidence of the contribution of HCMV IE1 protein to enhanced cytopathogenic responses in active HSV-1 infection.
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Humans , Cell Line, Tumor , Giant Cells/virology , Herpesvirus 1, Human/growth & development , Immediate-Early Proteins/biosynthesis , Protein Kinase Inhibitors/pharmacology , Purines/pharmacology , Transfection , Virus Replication/drug effectsABSTRACT
Objective To investigate the effect of Mlot-4 cells onset with Roscovitine (ROSC)as some Cyclin-dependent kinases(CDK),inhibitor.Methods The logarithmic growth phase Molt-4 cells treated with ROSC at a final concentration ranging between 1～20 μmol/L and harvested in different time point,DNA assay of single cells by flow cytometry was used to detect the effect of cell cycle arrest and Annexin-V/FITC assay was used to detect the effect of cell apoptosis. Results It showed that ROSC exerted strong inhibitory effect on proliferation and cell cycle progression of Molt-4 Accumulation of G2/M arrested cells starting 6 h after onset of 10 μmol/L and 20 μmol/L ROSC;at the same time,the cell apoptosis of Molt-4 would be detected,According with the time and concentration changing,the cell apoptosis rate would rise.Conclusion It is concluded that Roscovitine(ROSC)as some Cyclin-dependent kinases(CDK),inhibitor,It has dual effects to Molt-4 cells,not only the effect of cell cycle arrest but also the effect of cell apoptosis.