The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Jung-hye Choi - One of the best experts on this subject based on the ideXlab platform.
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the natural Terthiophene α terthienylmethanol induces s phase cell cycle arrest of human ovarian cancer cells via the generation of ros stress
Chemico-Biological Interactions, 2017Co-Authors: Umma Hafsa Preya, Dae Sik Jang, Kyungtae Lee, Namjung Kim, Jungyun Lee, Jung-hye ChoiAbstract:Ovarian cancer is the most lethal gynecological malignancy worldwide. Thiophenes such as Terthiophene have been shown to have anti-tumor effects on several cancer cell lines, including ovarian cancer cells. However, the underlying mechanisms behind the anti-proliferative effect of thiophenes are poorly understood. In this study, we investigated the molecular mechanisms underlying the anti-proliferative effect of α-terthienylmethanol, a Terthiophene isolated from Eclipta prostrata (False Daisy), on human ovarian cancer cells. We found that α-terthienylmethanol is a more potent inhibitor of cell growth than is cisplatin in human ovarian cancer cells. α-Terthienylmethanol induces cell cycle arrest in ovarian cancer cells, as shown by the accumulation of cells in S phase. In addition, α-terthienylmethanol induced a change in S phase-related proteins cyclin A, cyclin-dependent kinase 2, and cyclin D2. Knockdown of cyclin A using specific siRNAs significantly compromised α-terthienylmethanol-induced S phase arrest. We further demonstrated that α-terthienylmethanol induced an increase in intracellular ROS, and the antioxidant N-acetyl-l-cysteine significantly reversed the S phase arrest induced by α-terthienylmethanol. Moreover, α-terthienylmethanol significantly increased the levels of p-H2AX, a DNA damage marker. These results suggest that α-terthienylmethanol inhibits the growth of human ovarian cancer cells by S phase cell cycle arrest via induction of ROS stress and DNA damage.
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Constituents of the aerial parts of Eclipta prostrata and their cytotoxicity on human ovarian cancer cells in vitro
Archives of Pharmacal Research, 2015Co-Authors: Ha-yeong Kim, Hye Mi Kim, Byeol Ryu, Jae-seung Lee, Jung-hye Choi, Dae Sik JangAbstract:A new Terthiophene, 3′-hydroxy-2,2′:5′,2″-Terthiophene-3′- O - β - d -glucopyranoside ( 1 ) and a new oleanane-type saponin, echinocystic acid-3- O -(6- O -acetyl)- β - d -glucopyranoside ( 7 ) were isolated from the aerial parts of Eclipta prostrata L. Moreover, five thiophenes ( 2 – 6 ), seven triterpenoids ( 8 – 14 ), two coumestans ( 15 and 16 ), and four flavonoids ( 17 – 20 ) having previously known chemical structures were isolated during the same course of this study. All the isolates 1 – 20 were evaluated for their cytotoxicity against human ovarian cancer cells (SKOV3) using MTT assays.
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α terthienylmethanol isolated from eclipta prostrata induces apoptosis by generating reactive oxygen species via nadph oxidase in human endometrial cancer cells
Journal of Ethnopharmacology, 2015Co-Authors: Jae-seung Lee, Ha-yeong Kim, Dae Sik Jang, Jihye Ahn, Yoonjin Cho, Yeongin Yang, Kyungtae Lee, Jung-hye ChoiAbstract:Abstract Ethnopharmacological relevance Eclipta prostrate L. (syn. E. alba Hassk), commonly known as False Daisy, has been used in traditional medicine in Asia to treat a variety of diseases, including cancer. Although an anti-tumor effect has been suggested for E. prostrata, the exact anti-tumor effects and underlying molecular mechanisms of its bioactive compounds are poorly understood. The aim of this study was to identify compounds with anti-cancer activity from E. prostrata and to investigate their mechanism of action. Materials and methods To assess cell viability, cell cycle progression, and apoptosis, we performed MTT assays and FACS analysis using Annexin and PI staining. We also investigated reactive oxygen species (ROS) production and caspase activation using flow cytometry and Western blot analysis, respectively. Cytosolic translocation of cytochrome c was measured using an ELISA kit. Antioxidants, MAPK signaling inhibitors, NADPH oxidase inhibitors, and siRNA were used to elucidate the molecular mechanism of action of the compound. Results We isolated five Terthiophenes from the n-hexane fraction of E. prostrata; of these, α-terthienylmethanol possessed potent cytotoxic activity against human endometrial cancer cells (Hec1A and Ishikawa) (IC50 l -cysteine and catalase significantly attenuated α-terthienylmethanol-induced apoptosis. We further demonstrated that inhibition of the NADPH oxidase attenuated α-terthienylmethanol-induced cell death and ROS accumulation in endometrial cancer cells. Conclusion Overall, these results suggest that α-terthienylmethanol, a naturally occurring Terthiophene isolated from E. prostrata, induces apoptosis in human endometrial cancer cells by ROS production, partially via NADPH oxidase.
Valery N Charushin - One of the best experts on this subject based on the ideXlab platform.
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a convenient synthesis of new 5 11 dihydroindolo 3 2 b carbazoles bearing thiophene 2 2 bithiophene or 2 2 5 2 Terthiophene units at c 2 and c 8 positions
Tetrahedron Letters, 2017Co-Authors: Roman A Irgashev, Nikita A Kazin, Gennady L Rusinov, Valery N CharushinAbstract:Abstract A series of new 5,11-dihydroindolo[3,2-b]carbazole derivatives, containing functional thiophene, 2,2′-bithiophene or 2,2′:5′,2″-Terthiophene moieties at both C-2 and C-8 positions of their fused scaffolds, have been obtained from 2,8-diacetyl-substituted 5,11-dihydroindolo[3,2-b]carbazole compounds through the effective strategy, which is based on the sequence of two reactions, namely the Vilsmeier–Haack formylation and the Fiesselmann thiophene synthesis. The starting acetyl substituted materials have been transformed into the corresponding 3-chlorocrylaldehyde-containing compounds by treatment with POCl3-DMF complex, followed by the reaction with alkyl thioglycolates or α-mercaptoacetone in the presence of triethylamine to afford 2-carboalkoxythiophene- or 2-acetylthiophene-linked derivatives. 2-Acetylthiophene derivatives have further been involved into the same sequence of reactions to obtain 2,2′-bithiophene-, and 2,2′:5′,2″-Terthiophene-linked 5,11-dihydroindolo[3,2-b]carbazole compounds.
A S Fisyuk - One of the best experts on this subject based on the ideXlab platform.
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a simple and efficient synthesis of substituted 2 2 bithiophene and 2 2 5 2 Terthiophene
Organic Letters, 2014Co-Authors: Anastasia S Kostyuchenko, Alexey M Averkov, A S FisyukAbstract:A simple and efficient approach is developed for the synthesis of substituted 2,2′-bithiophene- and 2,2′:5′,2″-Terthiophene-5-carboxylic acids and esters which is based on thiophene ring closure in the Fiesselmann reaction. Using this method, derivatives containing a long alkyl chain with or without an end functional group or an aryl substituent can be conveniently prepared.
Dae Sik Jang - One of the best experts on this subject based on the ideXlab platform.
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the natural Terthiophene α terthienylmethanol induces s phase cell cycle arrest of human ovarian cancer cells via the generation of ros stress
Chemico-Biological Interactions, 2017Co-Authors: Umma Hafsa Preya, Dae Sik Jang, Kyungtae Lee, Namjung Kim, Jungyun Lee, Jung-hye ChoiAbstract:Ovarian cancer is the most lethal gynecological malignancy worldwide. Thiophenes such as Terthiophene have been shown to have anti-tumor effects on several cancer cell lines, including ovarian cancer cells. However, the underlying mechanisms behind the anti-proliferative effect of thiophenes are poorly understood. In this study, we investigated the molecular mechanisms underlying the anti-proliferative effect of α-terthienylmethanol, a Terthiophene isolated from Eclipta prostrata (False Daisy), on human ovarian cancer cells. We found that α-terthienylmethanol is a more potent inhibitor of cell growth than is cisplatin in human ovarian cancer cells. α-Terthienylmethanol induces cell cycle arrest in ovarian cancer cells, as shown by the accumulation of cells in S phase. In addition, α-terthienylmethanol induced a change in S phase-related proteins cyclin A, cyclin-dependent kinase 2, and cyclin D2. Knockdown of cyclin A using specific siRNAs significantly compromised α-terthienylmethanol-induced S phase arrest. We further demonstrated that α-terthienylmethanol induced an increase in intracellular ROS, and the antioxidant N-acetyl-l-cysteine significantly reversed the S phase arrest induced by α-terthienylmethanol. Moreover, α-terthienylmethanol significantly increased the levels of p-H2AX, a DNA damage marker. These results suggest that α-terthienylmethanol inhibits the growth of human ovarian cancer cells by S phase cell cycle arrest via induction of ROS stress and DNA damage.
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Constituents of the aerial parts of Eclipta prostrata and their cytotoxicity on human ovarian cancer cells in vitro
Archives of Pharmacal Research, 2015Co-Authors: Ha-yeong Kim, Hye Mi Kim, Byeol Ryu, Jae-seung Lee, Jung-hye Choi, Dae Sik JangAbstract:A new Terthiophene, 3′-hydroxy-2,2′:5′,2″-Terthiophene-3′- O - β - d -glucopyranoside ( 1 ) and a new oleanane-type saponin, echinocystic acid-3- O -(6- O -acetyl)- β - d -glucopyranoside ( 7 ) were isolated from the aerial parts of Eclipta prostrata L. Moreover, five thiophenes ( 2 – 6 ), seven triterpenoids ( 8 – 14 ), two coumestans ( 15 and 16 ), and four flavonoids ( 17 – 20 ) having previously known chemical structures were isolated during the same course of this study. All the isolates 1 – 20 were evaluated for their cytotoxicity against human ovarian cancer cells (SKOV3) using MTT assays.
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α terthienylmethanol isolated from eclipta prostrata induces apoptosis by generating reactive oxygen species via nadph oxidase in human endometrial cancer cells
Journal of Ethnopharmacology, 2015Co-Authors: Jae-seung Lee, Ha-yeong Kim, Dae Sik Jang, Jihye Ahn, Yoonjin Cho, Yeongin Yang, Kyungtae Lee, Jung-hye ChoiAbstract:Abstract Ethnopharmacological relevance Eclipta prostrate L. (syn. E. alba Hassk), commonly known as False Daisy, has been used in traditional medicine in Asia to treat a variety of diseases, including cancer. Although an anti-tumor effect has been suggested for E. prostrata, the exact anti-tumor effects and underlying molecular mechanisms of its bioactive compounds are poorly understood. The aim of this study was to identify compounds with anti-cancer activity from E. prostrata and to investigate their mechanism of action. Materials and methods To assess cell viability, cell cycle progression, and apoptosis, we performed MTT assays and FACS analysis using Annexin and PI staining. We also investigated reactive oxygen species (ROS) production and caspase activation using flow cytometry and Western blot analysis, respectively. Cytosolic translocation of cytochrome c was measured using an ELISA kit. Antioxidants, MAPK signaling inhibitors, NADPH oxidase inhibitors, and siRNA were used to elucidate the molecular mechanism of action of the compound. Results We isolated five Terthiophenes from the n-hexane fraction of E. prostrata; of these, α-terthienylmethanol possessed potent cytotoxic activity against human endometrial cancer cells (Hec1A and Ishikawa) (IC50 l -cysteine and catalase significantly attenuated α-terthienylmethanol-induced apoptosis. We further demonstrated that inhibition of the NADPH oxidase attenuated α-terthienylmethanol-induced cell death and ROS accumulation in endometrial cancer cells. Conclusion Overall, these results suggest that α-terthienylmethanol, a naturally occurring Terthiophene isolated from E. prostrata, induces apoptosis in human endometrial cancer cells by ROS production, partially via NADPH oxidase.
Mats Andersson - One of the best experts on this subject based on the ideXlab platform.
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effect of alkyl side chain length on intra and intermolecular interactions of Terthiophene isoindigo copolymers
Journal of Physical Chemistry C, 2020Co-Authors: Mats Andersson, Newayemedhin A Tegegne, Zelalem Abdissa, Wendimagegn Mammo, Takayuki Uchiyama, Yoshiko Okadashudo, Francesco Galeotti, William Porzio, Derck SchlettweinAbstract:Two Terthiophene–isoindigo copolymers (P3TI-O and P3TI-D) were successfully designed and synthesized. Octyl (O) and dodecyl (D) alkyl side chains were appended at the third position of the first an...
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effect of alkyl side chain length on intra and intermolecular interactions of Terthiophene isoindigo copolymers
The Journal of Physical Chemistry, 2020Co-Authors: Mats Andersson, Newayemedhin A Tegegne, Zelalem Abdissa, Wendimagegn Mammo, Takayuki Uchiyama, Yoshiko Okadashudo, Francesco Galeotti, William Porzio, Derck SchlettweinAbstract:Two Terthiophene–isoindigo copolymers (P3TI-O and P3TI-D) were successfully designed and synthesized. Octyl (O) and dodecyl (D) alkyl side chains were appended at the third position of the first and fourth positions of the last thiophene on the Terthiophene donor units in P3TI-O and P3TI-D, respectively. The band gaps of these copolymers were less than 1.7 eV. We found intramolecular charge-transfer states in both copolymers, which were generated with time constants of 4.5 and 13 ps for the copolymers with short and long alkyl side chains on their donor units, respectively. These results indicate that an almost 3-fold faster intramolecular charge-transfer process occurs when the alkyl side chains are shortened by four methyl units. Owing to a better interchain charge transfer, P3TI-O exhibits a more efficient exciton diffusion compared to P3TI-D, thus leading to longer exciton lifetimes in the copolymer with shorter alkyl side chains. Consequently, when blended with PC₇₁BM in bulk heterojunctions, P3TI-O showed a better exciton dissociation efficiency compared to P3TI-D. These results correlate well with the higher short-circuit current densities observed in P3TI-O:PC₇₁BM inverted architecture organic solar cells compared to the P3TI-D:PC₇₁BM ones.
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An Easily Accessible Isoindigo-Based Polymer for High-Performance Polymer Solar Cells
Journal of the American Chemical Society, 2011Co-Authors: Ergang Wang, Olle Inganäs, Fengling Zhang, Zhen Zhang, Koen Vandewal, Patrik Henriksson, Mats AnderssonAbstract:A new, low-band-gap alternating copolymer consisting of Terthiophene and isoindigo has been designed and synthesized. Solar cells based on this polymer and PC71BM show a power conversion efficiency of 6.3%, which is a record for polymer solar cells based on a polymer with an optical band gap below 1.5 eV. This work demonstrates the great potential of isoindigo moieties as electron-deficient units for building donor–acceptor-type polymers for high-performance polymer solar cells.