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Jan Barciszewski - One of the best experts on this subject based on the ideXlab platform.
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Kinetin—A multiactive molecule
International journal of biological macromolecules, 2006Co-Authors: Jan Barciszewski, Frank Massino, Brian F C ClarkAbstract:Cytokinins are important adenine derivatives that serve as hormones to control many processes in plants. They were discovered as factors that promote cell division in tobacco tissue cultures and have been shown also to regulate several other developmental events. Kinetin which was isolated 50 years ago for the first time as a plant hormone, as well as other cytokinins isopentenyladenine, zeatin and benzylaminopurine induce callus (clusters of dedifferentiated plant cells) to redifferentiate into adventitious buds. Because of some similarities in the biological phenotypes of cancer and callus cells, cytokinins and especially Kinetin, affect the differentiation of human cells through a common signal transduction system. Therefore, cytokinins found their way to use in molecular medicine.
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action at a distance of a new dna oxidative damage product 6 furfuryl adenine Kinetin on template properties of modified dna
Biochimica et Biophysica Acta, 2003Co-Authors: Eliza Wyszko, Brian F C Clark, Miroslawa Z Barciszewska, Maria Markiewicz, Maciej Szymanski, Wojciech T Markiewicz, Jan BarciszewskiAbstract:N(6)-furfuryladenine (Kinetin, K) was shown to have cytokinin activity and antiageing effects. It also appears to protect DNA against oxidative damage mediated by the Fenton reaction. Kinetin was identified as a natural component of DNA in plant extract, calf thymus DNA, fresh DNA preparations from human cell culture, as well as in human urine. A proposed mechanism of Kinetin synthesis includes furfural, the oxidative damage product of a 2-deoxyribose moiety of DNA, which reacts with an adenine residue to form N(6)-furfuryladenine at DNA level. The identification of Kinetin in plant cell extracts, as well as human urine, suggests its excision from DNA by repair mechanisms. Since such a bulky modification as Kinetin induces conformational changes of DNA, this could lead to mutations. Therefore, it was interesting to analyze an effect of Kinetin on coding properties of DNA. Chemically synthesized oligodeoxynucleotide (20-mer) containing Kinetin AAAACTGCCGTCCTGAKGAT was used as a primer. It was elongated in a polymerase chain reaction (PCR) on a template plasmid pEW1 harboring a 210-bp fragment of DNA derived from the 5' end of HIV mRNA. The PCR product of that length containing Kinetin in position 17 from the 5' end was isolated and sequenced. Interestingly, DNA polymerase correctly incorporates thymine opposite of Kinetin (an adenine derivative) on the complementary strand, but the misincorporations occur in a vicinity of the modified base.
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Kinetin — 45 years on
Plant Science, 1999Co-Authors: Jan Barciszewski, Gunhild E Siboska, Suresh I S Rattan, Brian F C ClarkAbstract:Abstract Kinetin (N 6 -furfuryladenine) was the first cytokinin to be isolated almost 45 years ago from DNA as an artifactual rearrangement product of the autoclaving process. Since then its chemical structure and properties have been well described. Most importantly, a wide variety of biological effects of Kinetin, including those on gene expression, on inhibition of auxin action, on stimulation of calcium flux, on cell cycle, and as an anti-stress and anti-ageing compound have been reported. Recently, views on this very well known plant growth factor have undergone substantial modifications. New data have appeared which show that Kinetin is formed in cellular DNA as the product of the oxidative, secondary modification of DNA. Although the biological significance of the endogenous Kinetin and the molecular mechanisms of its action are not completely understood at present, most of the experimental data point toward Kinetin acting as a strong antioxidant in vitro and in vivo, with potential beneficial uses in agriculture and human healthcare.
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Biological Activities of Kinetin
Herbal Drugs: Ethnomedicine to Modern Medicine, 1Co-Authors: Kalina Duszka, Brian F C Clark, Frank Massino, Jan BarciszewskiAbstract:Kinetin (N6-furfuryladenine) is a cytokinin growth factor with several biological effects observed for human cells and fruit flies. It was given the name Kinetin because of its ability to induce cell division. Kinetin is often used in plant cell and tissue culture for induction of callus formation (in conjunction with auxin) and to regenerate shoots from callus (with lower auxin concentration). Kinetin exists naturally in the DNA of almost all organisms tested so far, including human cells, and various plants. The mechanism of Kinetin synthesis in DNA is thought to be via the production of furfural, an oxidative damage product of DNA deoxyribose, and it is quenched by the adenine base converting it into N6-furfuryladenine. Since 1994 Kinetin has been thoroughly tested for its powerful antiaging effects in human skin cells and other systems. At present, Kinetin is one of the most widely used components in numerous skin care cosmetics and cosmeceuticals. There are some reports published on other biological effects of Kinetin in human beings, as an antiplatelet aggregation factor reducing thrombus formation, and its ability to correct genetic diseases of RNA missplicing. Kinetin was shown to be more effective in the improvement of skin texture, making it smoother and with a significant reduction in fine lines and wrinkles. It is a stable antioxidant that slows down the aging process.
Himanshu A. Pandya - One of the best experts on this subject based on the ideXlab platform.
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Prediction of protein targets of Kinetin using in silico and in vitro methods: a case study on spinach seed germination mechanism
Journal of Chemical Biology, 2015Co-Authors: Sivakumar Prasanth Kumar, Vilas R. Parmar, Yogesh T. Jasrai, Himanshu A. PandyaAbstract:Kinetin, a cytokinin which promotes seed germination by inhibiting the action of abscisic acid, is an important molecule known to trigger various molecular mechanisms by interacting with an array of proteins shown from experimental observations in various model organisms. We report here the prediction of most probable protein targets of Kinetin from spinach proteome using in silico approaches. Inverse docking and ligand-based similarity search was performed using Kinetin as molecule. The former method prioritized six spinach proteins, whereas the latter method provided a list of protein targets retrieved from several model organisms. The most probable protein targets were selected by comparing the rank list of docking and ligand similarity methods. Both of these methods prioritized chitinase as the most probable protein target (Δ G _pred = 5.064 kcal/mol) supported by the experimental structure of yeast chitinase 1 complex with Kinetin (PDB: 2UY5) and Gliocladium roseum chitinase complex with 3,7-dihydro-1,3,7-trimethyl-1H-purine-2,6-dione (caffeine; 3G6M) which bears a 3D similarity of 0.43 with Kinetin. An in vitro study to evaluate the effect of Kinetin on spinach seed germination indicated that a very low concentration of Kinetin (0.5 mg/l) did not show a significant effect compared to control in inducing seed germination process. Further, higher levels of Kinetin (>0.5 mg/l) constituted an antagonist effect on spinach seed germination. It is anticipated that Kinetin may have a molecular interaction with prioritized protein targets synthesized during the seed germination process and reduces growth. Thus, it appears that Kinetin may not be a suitable hormone for enhancing spinach seed germination in vitro.
Brian F C Clark - One of the best experts on this subject based on the ideXlab platform.
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Kinetin—A multiactive molecule
International journal of biological macromolecules, 2006Co-Authors: Jan Barciszewski, Frank Massino, Brian F C ClarkAbstract:Cytokinins are important adenine derivatives that serve as hormones to control many processes in plants. They were discovered as factors that promote cell division in tobacco tissue cultures and have been shown also to regulate several other developmental events. Kinetin which was isolated 50 years ago for the first time as a plant hormone, as well as other cytokinins isopentenyladenine, zeatin and benzylaminopurine induce callus (clusters of dedifferentiated plant cells) to redifferentiate into adventitious buds. Because of some similarities in the biological phenotypes of cancer and callus cells, cytokinins and especially Kinetin, affect the differentiation of human cells through a common signal transduction system. Therefore, cytokinins found their way to use in molecular medicine.
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action at a distance of a new dna oxidative damage product 6 furfuryl adenine Kinetin on template properties of modified dna
Biochimica et Biophysica Acta, 2003Co-Authors: Eliza Wyszko, Brian F C Clark, Miroslawa Z Barciszewska, Maria Markiewicz, Maciej Szymanski, Wojciech T Markiewicz, Jan BarciszewskiAbstract:N(6)-furfuryladenine (Kinetin, K) was shown to have cytokinin activity and antiageing effects. It also appears to protect DNA against oxidative damage mediated by the Fenton reaction. Kinetin was identified as a natural component of DNA in plant extract, calf thymus DNA, fresh DNA preparations from human cell culture, as well as in human urine. A proposed mechanism of Kinetin synthesis includes furfural, the oxidative damage product of a 2-deoxyribose moiety of DNA, which reacts with an adenine residue to form N(6)-furfuryladenine at DNA level. The identification of Kinetin in plant cell extracts, as well as human urine, suggests its excision from DNA by repair mechanisms. Since such a bulky modification as Kinetin induces conformational changes of DNA, this could lead to mutations. Therefore, it was interesting to analyze an effect of Kinetin on coding properties of DNA. Chemically synthesized oligodeoxynucleotide (20-mer) containing Kinetin AAAACTGCCGTCCTGAKGAT was used as a primer. It was elongated in a polymerase chain reaction (PCR) on a template plasmid pEW1 harboring a 210-bp fragment of DNA derived from the 5' end of HIV mRNA. The PCR product of that length containing Kinetin in position 17 from the 5' end was isolated and sequenced. Interestingly, DNA polymerase correctly incorporates thymine opposite of Kinetin (an adenine derivative) on the complementary strand, but the misincorporations occur in a vicinity of the modified base.
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n6 furfuryladenine Kinetin protects against fenton reaction mediated oxidative damage to dna
Biochemical and Biophysical Research Communications, 1999Co-Authors: Anders Olsen, Gunhild E Siboska, Brian F C Clark, Suresh I S RattanAbstract:N6-Furfuryladenine (Kinetin) has been shown to have anti-ageing effects on several different systems including plants, human cells in culture, and fruitflies. Since most of the experimental data point toward Kinetin acting as an antioxidant both in vitro and in vivo, and since much evidence supporting a causal role of oxidative damage in ageing is accumulating, we tested the antioxidant properties of Kinetin directly. Using 8-oxo-2′deoxyguanosine (8-oxo-dG) in calf thymus DNA as a marker for oxidative damage, we demonstrate that Kinetin significantly (P < 0.005) protects the DNA against oxidative damage mediated by the Fenton reaction. Kinetin inhibited 8-oxo-dG formation in a dose-dependent manner with a maximum of 50% protection observed at 100 μM Kinetin.
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Kinetin — 45 years on
Plant Science, 1999Co-Authors: Jan Barciszewski, Gunhild E Siboska, Suresh I S Rattan, Brian F C ClarkAbstract:Abstract Kinetin (N 6 -furfuryladenine) was the first cytokinin to be isolated almost 45 years ago from DNA as an artifactual rearrangement product of the autoclaving process. Since then its chemical structure and properties have been well described. Most importantly, a wide variety of biological effects of Kinetin, including those on gene expression, on inhibition of auxin action, on stimulation of calcium flux, on cell cycle, and as an anti-stress and anti-ageing compound have been reported. Recently, views on this very well known plant growth factor have undergone substantial modifications. New data have appeared which show that Kinetin is formed in cellular DNA as the product of the oxidative, secondary modification of DNA. Although the biological significance of the endogenous Kinetin and the molecular mechanisms of its action are not completely understood at present, most of the experimental data point toward Kinetin acting as a strong antioxidant in vitro and in vivo, with potential beneficial uses in agriculture and human healthcare.
-
Biological Activities of Kinetin
Herbal Drugs: Ethnomedicine to Modern Medicine, 1Co-Authors: Kalina Duszka, Brian F C Clark, Frank Massino, Jan BarciszewskiAbstract:Kinetin (N6-furfuryladenine) is a cytokinin growth factor with several biological effects observed for human cells and fruit flies. It was given the name Kinetin because of its ability to induce cell division. Kinetin is often used in plant cell and tissue culture for induction of callus formation (in conjunction with auxin) and to regenerate shoots from callus (with lower auxin concentration). Kinetin exists naturally in the DNA of almost all organisms tested so far, including human cells, and various plants. The mechanism of Kinetin synthesis in DNA is thought to be via the production of furfural, an oxidative damage product of DNA deoxyribose, and it is quenched by the adenine base converting it into N6-furfuryladenine. Since 1994 Kinetin has been thoroughly tested for its powerful antiaging effects in human skin cells and other systems. At present, Kinetin is one of the most widely used components in numerous skin care cosmetics and cosmeceuticals. There are some reports published on other biological effects of Kinetin in human beings, as an antiplatelet aggregation factor reducing thrombus formation, and its ability to correct genetic diseases of RNA missplicing. Kinetin was shown to be more effective in the improvement of skin texture, making it smoother and with a significant reduction in fine lines and wrinkles. It is a stable antioxidant that slows down the aging process.
Sivakumar Prasanth Kumar - One of the best experts on this subject based on the ideXlab platform.
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Prediction of protein targets of Kinetin using in silico and in vitro methods: a case study on spinach seed germination mechanism
Journal of Chemical Biology, 2015Co-Authors: Sivakumar Prasanth Kumar, Vilas R. Parmar, Yogesh T. Jasrai, Himanshu A. PandyaAbstract:Kinetin, a cytokinin which promotes seed germination by inhibiting the action of abscisic acid, is an important molecule known to trigger various molecular mechanisms by interacting with an array of proteins shown from experimental observations in various model organisms. We report here the prediction of most probable protein targets of Kinetin from spinach proteome using in silico approaches. Inverse docking and ligand-based similarity search was performed using Kinetin as molecule. The former method prioritized six spinach proteins, whereas the latter method provided a list of protein targets retrieved from several model organisms. The most probable protein targets were selected by comparing the rank list of docking and ligand similarity methods. Both of these methods prioritized chitinase as the most probable protein target (Δ G _pred = 5.064 kcal/mol) supported by the experimental structure of yeast chitinase 1 complex with Kinetin (PDB: 2UY5) and Gliocladium roseum chitinase complex with 3,7-dihydro-1,3,7-trimethyl-1H-purine-2,6-dione (caffeine; 3G6M) which bears a 3D similarity of 0.43 with Kinetin. An in vitro study to evaluate the effect of Kinetin on spinach seed germination indicated that a very low concentration of Kinetin (0.5 mg/l) did not show a significant effect compared to control in inducing seed germination process. Further, higher levels of Kinetin (>0.5 mg/l) constituted an antagonist effect on spinach seed germination. It is anticipated that Kinetin may have a molecular interaction with prioritized protein targets synthesized during the seed germination process and reduces growth. Thus, it appears that Kinetin may not be a suitable hormone for enhancing spinach seed germination in vitro.
Joen Rong Sheu - One of the best experts on this subject based on the ideXlab platform.
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inhibitory activity of Kinetin on free radical formation of activated platelets in vitro and on thrombus formation in vivo
European Journal of Pharmacology, 2003Co-Authors: George Hsiao, Ming Yi Shen, Kuan Hung Lin, Chin Yi Chou, Nien Hsuan Tzu, Chienhuang Lin, Duen Suey Chou, Tzengfu Chen, Joen Rong SheuAbstract:Kinetin has been shown to have anti-aging effects on several different systems, including plants and human cells. Recently, we demonstrated that Kinetin markedly inhibited platelet aggregation in washed human platelets. In the present study, an electron spin resonance (ESR) method was used to further evaluate the scavenging activity of Kinetin on the free radicals formed. Kinetin (70 and 150 microM) concentration dependently reduced the ESR signal intensity of hydroxyl radicals in collagen (1 microg/ml)-activated platelets. Furthermore, Kinetin was effective in reducing the mortality of ADP-induced acute pulmonary thromboembolism in mice when administered intravenously at doses of 4 and 6 mg/kg. In addition, intravenous injection of Kinetin (4 and 6 mg/kg) significantly prolonged the bleeding time by approximately 1.9- and 2.1-fold as compared with normal saline in severed mesenteric arteries of rats. A continuous infusion of Kinetin (0.6 mg/kg/min) for 10 min also significantly increased the bleeding time by about 2.3-fold, and the bleeding time returned to baseline within 120 min after cessation of Kinetin infusion. Platelet thrombi formation was induced by irradiation of mesenteric venules with filtered light in mice pretreated intravenously with fluorescein sodium. When Kinetin was administered at 13 and 14 mg/kg in mice pretreated with fluorescein sodium (5 mg/kg), the occlusion time was significantly prolonged. In conclusion, these results suggest that Kinetin has effective free radical-scavenging activity in vitro and antithrombotic activity in vivo. Treatment with Kinetin may lower the risk of thromboembolic-related disorders. Therefore, Kinetin may be a potential therapeutic agent for arterial thrombosis, but its toxicity must be further assessed.
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Inhibitory mechanisms of Kinetin, a plant growth-promoting hormone, in platelet aggregation
Platelets, 2003Co-Authors: Joen Rong Sheu, George Hsiao, M. Y. Shen, C. Y. Chou, C. H. Lin, T. F. Chen, D. S. ChouAbstract:Kinetin has been shown to have anti-aging effects on several different systems including plants and human cells. The aim of this study was to examine the detailed inhibitory mechanisms of Kinetin in platelet aggregation. In this study, Kinetin concentration-dependently (50-150 μM) inhibited platelet aggregation in human platelets stimulated by agonists. Kinetin (70 and 150 μM) also concentration-dependently inhibited intracellular Ca2+ mobilization and phosphoinositide breakdown in platelets stimulated by collagen (1 μg/ml). Kinetin (70 and 150 μM) significantly inhibited thromboxane A2 formation stimulated by collagen (1 μg/ml) and arachidonic acid (60 μM) in human platelets. In addition, Kinetin (70 and 150 μM) significantly increased the formation of cyclic AMP. Intracellular pH values were measured spectrofluorometrically using the fluorescent probe BCECF-AM in platelets. The thrombin-evoked increase in pHi was markedly inhibited in the presence of Kinetin (70 and 150 μM). Rapid phosphorylation of a p...
