The Experts below are selected from a list of 7542 Experts worldwide ranked by ideXlab platform
Sadhna Joshi - One of the best experts on this subject based on the ideXlab platform.
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inhibition of human immunodeficiency virus 1 entry using vectors expressing a multimeric hammerhead ribozyme targeting the ccr5 mrna
Journal of General Virology, 2008Co-Authors: Reza Nazari, Xue Zhong, Sadhna JoshiAbstract:Rz1–7 is a multimeric hammerhead ribozyme targeting seven unique sites within the human CCR5 mRNA that is active in vitro. Mouse stem Cell virus-based MGIN and human immunodeficiency virus (HIV)-1-based HEG1 vectors were used to express Rz1–7 in a human CD4+ T Lymphoid Cell Line. Stable transductants expressed Rz1–7, which was further shown to be active, since CCR5 mRNA and surface CCR5 protein expression levels decreased. High levels of progeny virus were produced when the transduced Cells were challenged with an X4-tropic HIV-1 (NL4-3) strain, suggesting that Rz1–7 expression does not affect X4-tropic virus replication. When the transduced Cells expressing Rz1–7 were challenged with the R5-tropic HIV-1 (BaL) strain, 99–100 % inhibition of progeny virus production was observed for the duration of the experiment (∼2 months). When the Cells were precultured for 2–3 months prior to HIV-1 infection, inhibition was more prominent in Cells transduced with MGIN-Rz1–7 than with HEG1-Rz1–7. Inhibition occurred at the level of viral entry, as no HIV-1 DNA could be detected. These results demonstrate that Rz1–7 confers exCellent inhibition of R5-tropic HIV-1 replication at the level of entry. Therefore, we anticipate that this multimeric ribozyme will be beneficial for HIV-1 gene therapy.
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assessment of an anti hiv 1 combination gene therapy strategy using the antisense rna and multimeric hammerhead ribozymes
Frontiers in Bioscience, 2006Co-Authors: Ali Ramezani, Xue Zhong, Masoud Ameli, Alka Arora, Sadhna JoshiAbstract:: A combination gene therapy strategy using an ASPsi-gag antisense RNA (targeted against the packaging signal and the gag-coding region) and a multimeric hammerhead ribozyme Rz1-9 (targeted against nine sites within the env-coding region) or Rz1-14 (targeted against 14 sites within the 5' leader and the pro-, pol-, vif- and env-coding regions) was assessed for inhibiting HIV-1 replication. A murine stem Cell virus (MSCV)-based MGIN vector was used to express Rz1-9, Rz1-14, ASPsi-gag, Rz1-9ASPsi-gag, or Rz1-14ASPsi-gag RNA in a CD4+ T Lymphoid Cell Line. Stable transductants were shown to express similar levels of interfering RNA. HIV-1 replication was inhibited in Cells expressing Rz1-9 and Rz1-14. Little inhibition of HIV-1 replication was observed in Cells expressing ASPsi-gag RNA. Thus, the multimeric hammerhead ribozymes inhibit HIV-1 replication better than the antisense RNA. Inhibition of HIV-1 replication in Cells expressing Rz1-9ASPsi-gag or Rz1-14ASPsi-gag RNA was worse than that obtained with the multimeric ribozymes alone. This result suggests that co-expression of antisense RNA decreases the anti-HIV potential of ribozymes. The multimeric ribozymes and the antisense RNA were designed to target different sites within the HIV-1 RNA. They are not expected to interact with each other. Neither are they expected to compete with each other for binding to the HIV-1 RNA. Instead, the antisense RNA binding to its (1553 nt-long) target site may have resulted in a decreased ribozyme turn over. Furthermore, since the antisense RNA/HIV-1 RNA hybrids are degraded by the Cells, the co-expressed antisense RNA may have led to ribozyme degradation.
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a combination anti hiv 1 gene therapy approach using a single transcription unit that expresses antisense decoy and sense rnas and trans dominant negative mutant gag and env proteins
Frontiers in Bioscience, 2002Co-Authors: Shifa Ding, Reza Nazari, Rocco Lombardi, Sadhna JoshiAbstract:Oncoretroviral vectors were engineered to allow constitutive expression of an antisense RNA and the trans-activator of transcription (Tat)-inducible expression of a mRNA containing the trans-activation response (TAR) element, the Rev response element (RRE), and the efficient packaging signal (Psi(e) of human immunodeficiency virus-1 (HIV-1) RNA. Nuclear export of this mRNA by the regulator of expression of virion proteins (Rev) would allow its translation into wild type (WT) (MoTN-Ti-GE-Ri- Ter) or trans-dominant negative mutant (TDM) (MoTN-Ti-GmEm-Ri-Ter) Gag and Env proteins. Thus, the antisense RNA produced in a constitutive manner would ensure that even if there is leaky expression, no WT/TDM Gag or Env protein would be produced in the uninfected Cells. If Cells become infected by HIV-1, the antisense RNA would inhibit HIV-1 replication. Failure on the part of antisense RNA to inhibit virus replication would allow GE/GmEm mRNA production. The GE/GmEm mRNA would cause partial inhibition of HIV-1 replication as it contains the TAR, RRE, and Psi(e) signal sequences. Translation of GmEm mRNA would give rise to TDM Gag and Env proteins, which would further decrease progeny virus infectivity. Tat- and Rev-inducibility was demonstrated in transfected HeLa and HeLa-Tev Cells. Full-length WT/TDM Gag production was confirmed by Western blot analysis. Amphotropic vector particles were used to transduce a human CD4+ T-Lymphoid Cell Line, and the stable transductants were challenged with HIV-1. Virus replication was better inhibited by the MoTN-Ti-GE-Ri-Ter vector than by the MoTN-Ti-GmEm-Ri-Ter vector. Inhibition of HIV-1 replication was also demonstrated in transduced CD4+ human peripheral blood T lymphocytes (PBLs). Moreover, our results suggest that cloning in the reverse transcriptional orientation must be avoided to prevent antisense RNA-mediated inhibition of transgene and endogenous gene expression.
Tomohiro Itoh - One of the best experts on this subject based on the ideXlab platform.
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antiproliferative effects of zerumbone pendant derivatives on human t Cell Lymphoid Cell Line jurkat Cells
Tetrahedron, 2019Co-Authors: Yoshimi Utaka, Tomohiro Itoh, Keitaro Sumi, Gengo Kashiwazaki, Sachiko Tajima, Yuko Fujiwara, Takashi KitayamaAbstract:Abstract Zerumbone is the major component of the essential oil of wild ginger, Zingiber zerumbet Smith. It is not only highly reactive but also has diverse bioactivities. Those effects derive from two conjugated double bonds of zerumbone and a carbonyl group in between, and we had already established a synthetic scheme for zerumbone-pendant derivatives without disturbing the conjugation system. Herein, twelve conjugates with salicylic acid or various benzoic acid derivatives were synthesized for evaluations of their antiproliferative effects on Jurkat Cells as salicylic acid is bioactive and has a carboxylic group for coupling. Most of them resulted in IC50 values as low as 1–10 μM, validating the utility of this activity-conserving strategy.
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phytol isolated from watermelon citrullus lanatus sprouts induces Cell death in human t Lymphoid Cell Line jurkat Cells via s phase Cell cycle arrest
Food and Chemical Toxicology, 2018Co-Authors: Tomohiro Itoh, Akito Ono, Kaori Kawaguchi, Sayaka Teraoka, Mayo Harada, Keitaro Sumi, Masashi Ando, Yasuyuki Tsukamasa, Masayuki NinomiyaAbstract:The phytol isolated from watermelon (Citrullus lanatus) sprouts inhibited the growth of a human T-Cell leukemia Line Jurkat Cell and suppressed tumor progression in a xenograft model of human lung adenocarcinoma epithelial Cell Line A549 in nude mice. To elucidate the mechanisms underlying the phytol-induced Cell death in the present study, we examined the changes in Cell morphology, DNA fragmentation, and intraCellular reactive oxygen species (ROS) levels and performed flow cytometric analysis to evaluate Cell cycle stage. There were no significant changes in apoptosis, autophagy, and necrosis marker in Cells treated with the phytol. But, we found, for the first time, that phytol remarkably induced S-phase Cell cycle arrest accompanied with intraCellular ROS production. Western blot analyses showed that phytolinduced S-phase Cell cycle arrest was mediated through the decreased expression of cyclins A and D and the downregulations of MAPK and PI3K/Akt. The tumor volume levels in mice treated with phytol were lower than those of non-treatment groups, and it showed very similar suppression compared with those of mice treated with cyclophosphamide. Based on the data of in vitro and in vivo studies and previous studies, we suggest phytol as a potential therapeutic compound for cancer.
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reduced scytonemin isolated from nostoc commune induces autophagic Cell death in human t Lymphoid Cell Line jurkat Cells
Food and Chemical Toxicology, 2013Co-Authors: Tomohiro Itoh, Hiroyuki Takenaka, Yuji Yamaguchi, Masashi Ando, Yasuyuki Tsukamasa, Masayuki Ninomiya, Ryosuke Tsuzuki, Toshiomi Tanaka, Mamoru KoketsuAbstract:Nostoc commune is a terrestrial benthic blue-green alga that often forms an extended mucilaginous layer on the soil, accumulates on stones and mud in aquatic environments. Reduced-scytonemin (R-scy), isolated from N. commune Vaucher, has been shown to suppress the human T-Lymphoid Jurkat Cell growth. To reveal the mechanisms underlying the R-scy-mediated inhibition of Jurkat Cell growth, we examined Cell morphology, DNA fragmentation, and microtubule-associated protein light chain 3 (LC3) modification in these Cells. We observed multiple vacuoles as well as the conversion of LC3-I to LC3-II in R-scy-treated Cells. These results suggest that the R-scy induced Jurkat Cell growth inhibition is attributable to the induction of type II programmed Cell death (PCD II; autophagic Cell death or autophagy). We further examined the mechanisms underlying R-scy-induced PCDII. The Cells treated with R-scy produced large amounts of reactive oxygen species (ROS), leading to the induction of mitochondrial dysfunction. However, the elimination of R-scy-induced ROS by treatment with N-acetyl-l-cysteine (NAC) markedly opposed R-scy-induced PCDII. Based on these results, we conclude that ROS formation plays a critical role in R-scy-induced PCDII.
Masayuki Ninomiya - One of the best experts on this subject based on the ideXlab platform.
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phytol isolated from watermelon citrullus lanatus sprouts induces Cell death in human t Lymphoid Cell Line jurkat Cells via s phase Cell cycle arrest
Food and Chemical Toxicology, 2018Co-Authors: Tomohiro Itoh, Akito Ono, Kaori Kawaguchi, Sayaka Teraoka, Mayo Harada, Keitaro Sumi, Masashi Ando, Yasuyuki Tsukamasa, Masayuki NinomiyaAbstract:The phytol isolated from watermelon (Citrullus lanatus) sprouts inhibited the growth of a human T-Cell leukemia Line Jurkat Cell and suppressed tumor progression in a xenograft model of human lung adenocarcinoma epithelial Cell Line A549 in nude mice. To elucidate the mechanisms underlying the phytol-induced Cell death in the present study, we examined the changes in Cell morphology, DNA fragmentation, and intraCellular reactive oxygen species (ROS) levels and performed flow cytometric analysis to evaluate Cell cycle stage. There were no significant changes in apoptosis, autophagy, and necrosis marker in Cells treated with the phytol. But, we found, for the first time, that phytol remarkably induced S-phase Cell cycle arrest accompanied with intraCellular ROS production. Western blot analyses showed that phytolinduced S-phase Cell cycle arrest was mediated through the decreased expression of cyclins A and D and the downregulations of MAPK and PI3K/Akt. The tumor volume levels in mice treated with phytol were lower than those of non-treatment groups, and it showed very similar suppression compared with those of mice treated with cyclophosphamide. Based on the data of in vitro and in vivo studies and previous studies, we suggest phytol as a potential therapeutic compound for cancer.
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reduced scytonemin isolated from nostoc commune induces autophagic Cell death in human t Lymphoid Cell Line jurkat Cells
Food and Chemical Toxicology, 2013Co-Authors: Tomohiro Itoh, Hiroyuki Takenaka, Yuji Yamaguchi, Masashi Ando, Yasuyuki Tsukamasa, Masayuki Ninomiya, Ryosuke Tsuzuki, Toshiomi Tanaka, Mamoru KoketsuAbstract:Nostoc commune is a terrestrial benthic blue-green alga that often forms an extended mucilaginous layer on the soil, accumulates on stones and mud in aquatic environments. Reduced-scytonemin (R-scy), isolated from N. commune Vaucher, has been shown to suppress the human T-Lymphoid Jurkat Cell growth. To reveal the mechanisms underlying the R-scy-mediated inhibition of Jurkat Cell growth, we examined Cell morphology, DNA fragmentation, and microtubule-associated protein light chain 3 (LC3) modification in these Cells. We observed multiple vacuoles as well as the conversion of LC3-I to LC3-II in R-scy-treated Cells. These results suggest that the R-scy induced Jurkat Cell growth inhibition is attributable to the induction of type II programmed Cell death (PCD II; autophagic Cell death or autophagy). We further examined the mechanisms underlying R-scy-induced PCDII. The Cells treated with R-scy produced large amounts of reactive oxygen species (ROS), leading to the induction of mitochondrial dysfunction. However, the elimination of R-scy-induced ROS by treatment with N-acetyl-l-cysteine (NAC) markedly opposed R-scy-induced PCDII. Based on these results, we conclude that ROS formation plays a critical role in R-scy-induced PCDII.
Reza Nazari - One of the best experts on this subject based on the ideXlab platform.
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inhibition of human immunodeficiency virus 1 entry using vectors expressing a multimeric hammerhead ribozyme targeting the ccr5 mrna
Journal of General Virology, 2008Co-Authors: Reza Nazari, Xue Zhong, Sadhna JoshiAbstract:Rz1–7 is a multimeric hammerhead ribozyme targeting seven unique sites within the human CCR5 mRNA that is active in vitro. Mouse stem Cell virus-based MGIN and human immunodeficiency virus (HIV)-1-based HEG1 vectors were used to express Rz1–7 in a human CD4+ T Lymphoid Cell Line. Stable transductants expressed Rz1–7, which was further shown to be active, since CCR5 mRNA and surface CCR5 protein expression levels decreased. High levels of progeny virus were produced when the transduced Cells were challenged with an X4-tropic HIV-1 (NL4-3) strain, suggesting that Rz1–7 expression does not affect X4-tropic virus replication. When the transduced Cells expressing Rz1–7 were challenged with the R5-tropic HIV-1 (BaL) strain, 99–100 % inhibition of progeny virus production was observed for the duration of the experiment (∼2 months). When the Cells were precultured for 2–3 months prior to HIV-1 infection, inhibition was more prominent in Cells transduced with MGIN-Rz1–7 than with HEG1-Rz1–7. Inhibition occurred at the level of viral entry, as no HIV-1 DNA could be detected. These results demonstrate that Rz1–7 confers exCellent inhibition of R5-tropic HIV-1 replication at the level of entry. Therefore, we anticipate that this multimeric ribozyme will be beneficial for HIV-1 gene therapy.
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a combination anti hiv 1 gene therapy approach using a single transcription unit that expresses antisense decoy and sense rnas and trans dominant negative mutant gag and env proteins
Frontiers in Bioscience, 2002Co-Authors: Shifa Ding, Reza Nazari, Rocco Lombardi, Sadhna JoshiAbstract:Oncoretroviral vectors were engineered to allow constitutive expression of an antisense RNA and the trans-activator of transcription (Tat)-inducible expression of a mRNA containing the trans-activation response (TAR) element, the Rev response element (RRE), and the efficient packaging signal (Psi(e) of human immunodeficiency virus-1 (HIV-1) RNA. Nuclear export of this mRNA by the regulator of expression of virion proteins (Rev) would allow its translation into wild type (WT) (MoTN-Ti-GE-Ri- Ter) or trans-dominant negative mutant (TDM) (MoTN-Ti-GmEm-Ri-Ter) Gag and Env proteins. Thus, the antisense RNA produced in a constitutive manner would ensure that even if there is leaky expression, no WT/TDM Gag or Env protein would be produced in the uninfected Cells. If Cells become infected by HIV-1, the antisense RNA would inhibit HIV-1 replication. Failure on the part of antisense RNA to inhibit virus replication would allow GE/GmEm mRNA production. The GE/GmEm mRNA would cause partial inhibition of HIV-1 replication as it contains the TAR, RRE, and Psi(e) signal sequences. Translation of GmEm mRNA would give rise to TDM Gag and Env proteins, which would further decrease progeny virus infectivity. Tat- and Rev-inducibility was demonstrated in transfected HeLa and HeLa-Tev Cells. Full-length WT/TDM Gag production was confirmed by Western blot analysis. Amphotropic vector particles were used to transduce a human CD4+ T-Lymphoid Cell Line, and the stable transductants were challenged with HIV-1. Virus replication was better inhibited by the MoTN-Ti-GE-Ri-Ter vector than by the MoTN-Ti-GmEm-Ri-Ter vector. Inhibition of HIV-1 replication was also demonstrated in transduced CD4+ human peripheral blood T lymphocytes (PBLs). Moreover, our results suggest that cloning in the reverse transcriptional orientation must be avoided to prevent antisense RNA-mediated inhibition of transgene and endogenous gene expression.
Xue Zhong - One of the best experts on this subject based on the ideXlab platform.
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inhibition of human immunodeficiency virus 1 entry using vectors expressing a multimeric hammerhead ribozyme targeting the ccr5 mrna
Journal of General Virology, 2008Co-Authors: Reza Nazari, Xue Zhong, Sadhna JoshiAbstract:Rz1–7 is a multimeric hammerhead ribozyme targeting seven unique sites within the human CCR5 mRNA that is active in vitro. Mouse stem Cell virus-based MGIN and human immunodeficiency virus (HIV)-1-based HEG1 vectors were used to express Rz1–7 in a human CD4+ T Lymphoid Cell Line. Stable transductants expressed Rz1–7, which was further shown to be active, since CCR5 mRNA and surface CCR5 protein expression levels decreased. High levels of progeny virus were produced when the transduced Cells were challenged with an X4-tropic HIV-1 (NL4-3) strain, suggesting that Rz1–7 expression does not affect X4-tropic virus replication. When the transduced Cells expressing Rz1–7 were challenged with the R5-tropic HIV-1 (BaL) strain, 99–100 % inhibition of progeny virus production was observed for the duration of the experiment (∼2 months). When the Cells were precultured for 2–3 months prior to HIV-1 infection, inhibition was more prominent in Cells transduced with MGIN-Rz1–7 than with HEG1-Rz1–7. Inhibition occurred at the level of viral entry, as no HIV-1 DNA could be detected. These results demonstrate that Rz1–7 confers exCellent inhibition of R5-tropic HIV-1 replication at the level of entry. Therefore, we anticipate that this multimeric ribozyme will be beneficial for HIV-1 gene therapy.
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assessment of an anti hiv 1 combination gene therapy strategy using the antisense rna and multimeric hammerhead ribozymes
Frontiers in Bioscience, 2006Co-Authors: Ali Ramezani, Xue Zhong, Masoud Ameli, Alka Arora, Sadhna JoshiAbstract:: A combination gene therapy strategy using an ASPsi-gag antisense RNA (targeted against the packaging signal and the gag-coding region) and a multimeric hammerhead ribozyme Rz1-9 (targeted against nine sites within the env-coding region) or Rz1-14 (targeted against 14 sites within the 5' leader and the pro-, pol-, vif- and env-coding regions) was assessed for inhibiting HIV-1 replication. A murine stem Cell virus (MSCV)-based MGIN vector was used to express Rz1-9, Rz1-14, ASPsi-gag, Rz1-9ASPsi-gag, or Rz1-14ASPsi-gag RNA in a CD4+ T Lymphoid Cell Line. Stable transductants were shown to express similar levels of interfering RNA. HIV-1 replication was inhibited in Cells expressing Rz1-9 and Rz1-14. Little inhibition of HIV-1 replication was observed in Cells expressing ASPsi-gag RNA. Thus, the multimeric hammerhead ribozymes inhibit HIV-1 replication better than the antisense RNA. Inhibition of HIV-1 replication in Cells expressing Rz1-9ASPsi-gag or Rz1-14ASPsi-gag RNA was worse than that obtained with the multimeric ribozymes alone. This result suggests that co-expression of antisense RNA decreases the anti-HIV potential of ribozymes. The multimeric ribozymes and the antisense RNA were designed to target different sites within the HIV-1 RNA. They are not expected to interact with each other. Neither are they expected to compete with each other for binding to the HIV-1 RNA. Instead, the antisense RNA binding to its (1553 nt-long) target site may have resulted in a decreased ribozyme turn over. Furthermore, since the antisense RNA/HIV-1 RNA hybrids are degraded by the Cells, the co-expressed antisense RNA may have led to ribozyme degradation.
