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 Posted: Sat Nov 22, 2008 12:39 am Post subject: Glutathione regulates telomerase activity in 3T3 fibroblasts |
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J Biol Chem. 2004 Aug 13;279(33):34332-5. Epub 2004 Jun 7.Click here
to read Links
Glutathione regulates telomerase activity in 3T3 fibroblasts.
Borrás C, Esteve JM, Viña JR, Sastre J, Viña J, Pallardó FV.
Department of Physiology, School of Medicine, University of
Valencia, Avda. Blasco Ibáñez 17, 46010 Valencia, Spain.
Changes in telomerase activity have been associated either with
cancer, when activity is increased, or with cell cycle arrest when it
is decreased. We report that glutathione, a physiological antioxidant
present at high intracellular concentrations, regulates telomerase
activity in cells in culture. Telomerase activity increases in 3T3
fibroblasts before exponential cell growth. The peak of telomerase
activity takes place 24 h after plating and coincides with the maximum
levels of glutathione in the cells. When cells are treated with
buthionine sulfoximine, which decreases glutathione levels in cells,
telomerase activity decreases by 60%, and cell growth is delayed.
Glutathione depletion inhibits expression of E2F4 and Id2, which
regulate the cell cycle. When glutathione levels are restored after
incubation with glutathione monoethylester, telomerase activity and
the cell cycle-related proteins return to control values. To discover
the effect of glutathione redox status on the telomerase multicomplex
structure, we incubated protein extracts from fibroblasts with
different glutathione redox buffers. Telomerase activity is maximal
under reduced conditions i.e. when the reduced/oxidized glutathione
ratio is high. Consequently glutathione concentration parallels
telomerase activity. These results underscore the main role of
glutathione in the control of telomerase activity and of the cell
cycle.
PMID: 15184392 [PubMed - indexed for MEDLINE]
Related Articles
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dependent modulation of nuclear import of transcription factors. [Cell
Death Differ. 2006]
* Redox state changes in density-dependent regulation of
proliferation. [Exp Cell Res. 1997]
* Redox control of G(1)/S cell cycle regulators during nitric
oxide-mediated cell cycle arrest. [J Cell Physiol. 2007]
* Resveratrol down-regulates the growth and telomerase
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» See Reviews... | » See All... |
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futurespeak
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| Posted: Sun Nov 23, 2008 7:02 pm Post subject: Re: Glutathione regulates telomerase activity in 3T3 fibrobl |
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On Nov 21, 4:39 pm, timoth...@my-deja.com wrote:
[quote]J Biol Chem. 2004 Aug 13;279(33):34332-5. Epub 2004 Jun 7.Click here
to read Links
Glutathione regulates telomerase activity in 3T3 fibroblasts.
Borrás C, Esteve JM, Viña JR, Sastre J, Viña J, Pallardó FV.
Department of Physiology, School of Medicine, University of
Valencia, Avda. Blasco Ibáñez 17, 46010 Valencia, Spain.
Changes in telomerase activity have been associated either with
cancer, when activity is increased, or with cell cycle arrest when it
is decreased. We report that glutathione, a physiological antioxidant
present at high intracellular concentrations, regulates telomerase
activity in cells in culture. Telomerase activity increases in 3T3
fibroblasts before exponential cell growth. The peak of telomerase
activity takes place 24 h after plating and coincides with the maximum
levels of glutathione in the cells. When cells are treated with
buthionine sulfoximine, which decreases glutathione levels in cells,
telomerase activity decreases by 60%, and cell growth is delayed.
Glutathione depletion inhibits expression of E2F4 and Id2, which
regulate the cell cycle. When glutathione levels are restored after
incubation with glutathione monoethylester, telomerase activity and
the cell cycle-related proteins return to control values. To discover
the effect of glutathione redox status on the telomerase multicomplex
structure, we incubated protein extracts from fibroblasts with
different glutathione redox buffers. Telomerase activity is maximal
under reduced conditions i.e. when the reduced/oxidized glutathione
ratio is high. Consequently glutathione concentration parallels
telomerase activity. These results underscore the main role of
glutathione in the control of telomerase activity and of the cell
cycle.
PMID: 15184392 [PubMed - indexed for MEDLINE]
Related Articles
* Regulation of osteoclast differentiation by the redox-
dependent modulation of nuclear import of transcription factors. [Cell
Death Differ. 2006]
* Redox state changes in density-dependent regulation of
proliferation. [Exp Cell Res. 1997]
* Redox control of G(1)/S cell cycle regulators during nitric
oxide-mediated cell cycle arrest. [J Cell Physiol. 2007]
* Resveratrol down-regulates the growth and telomerase
activity of breast cancer cells in vitro. [Int J Oncol. 2006]
* Review[Progress on telomere and telomerase] [Wei Sheng Yan
Jiu. 2004]
» See Reviews... | » See All...
Resveratrol down-regulates the growth and telomerase
activity of breast cancer cells in vitro. [Int J Oncol. 2006]
Resveratrol can also help you to lead a long and healthy life so says[/quote]
Dr. Oz.
Red wine alone does not supply enough resveratrol to achieve the
full range of benefits because one glass of red wine has only about
1mg of resveratrol and you need about 250mg/day. You need to take
high potency resveratrol supplements to achieve the results
documented
in scientific studies.Resveratrol Supplements can also help you
control
your weight naturally by increasing energy, reducing cravings, and
limiting
your appetite.According to Wikipedia, Consumer Lab, an independent
dietary
supplement and over the counter products evaluation organization,
published a report on 13 November 2007 on the popular resveratrol
supplements. The organization reported that there exists a wide
range
in quality, dose, and price among the 13 resveratrol products
evaluated. The actual amount of resveratrol contained in the
different brands range from 2.2mg for Revatrol, which claimed to
have
400mg of "Red Wine Grape Complex", to 500mg for Biotivia.com
Transmax,
which is consistent with the amount claimed on the product>s label.
Prices per 100mg of resveratrol ranged from less than $.30 for
products made by Biotivia.com, jarrow, and country life, to a high
of
$45.27 for the Revatrol brand. |
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