1: Aging Cell. 2007 Nov 14 [Epub ahead of print] Links
Black tea polyphenols mimic insulin/IGF-1 signalling to the longevity factor FOXO1a.Cameron AR, Anton S, Melville L, Houston NP, Dayal S, McDougall GJ, Stewart D, Rena G.
Neurosciences Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, DD1 9SY.
In vertebrates and invertebrates, relationships between diet and health are controlled by a conserved signalling pathway responsive to insulin-like ligands. In invertebrate models for example, FOXO transcription factors in this pathway regulate the rate of ageing in response to dietary cues and in vertebrates, obesity and age-induced deficits in the same pathway are thought to contribute to dysregulation of hepatic gluconeogenesis through genes such as phosphoenolpyruvate carboxykinase (PEPCK). Recently we have begun to screen for dietary constituents capable of regulating this pathway in our cell culture model. Here we identify three black tea theaflavins, theaflavin 3-O-gallate (TF(2)A), theaflavin 3'-O-gallate (TF(2)B) and theaflavin 3,3'di-O-gallate (TF(3)) and thearubigins as novel mimics of insulin/IGF-1 action on mammalian FOXO1a, PEPCK and moreover we provide evidence that the effects on this pathway of the green tea constituent EGCG depend on its ability to be converted into these larger structures. With the exception of water, tea is the most popular beverage globally but despite this little is known about the biological availability of black tea polyphenols in vivo or the molecular target(s) mediating the effects presented here. Further investigation in these two areas might provide insight into how age-related metabolic disease may be deferred.
Black tea polyphenols mimic insulin/IGF-1 signalling to the longevity factor FOXO1a.Cameron AR, Anton S, Melville L, Houston NP, Dayal S, McDougall GJ, Stewart D, Rena G.
Neurosciences Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, DD1 9SY.
In vertebrates and invertebrates, relationships between diet and health are controlled by a conserved signalling pathway responsive to insulin-like ligands. In invertebrate models for example, FOXO transcription factors in this pathway regulate the rate of ageing in response to dietary cues and in vertebrates, obesity and age-induced deficits in the same pathway are thought to contribute to dysregulation of hepatic gluconeogenesis through genes such as phosphoenolpyruvate carboxykinase (PEPCK). Recently we have begun to screen for dietary constituents capable of regulating this pathway in our cell culture model. Here we identify three black tea theaflavins, theaflavin 3-O-gallate (TF(2)A), theaflavin 3'-O-gallate (TF(2)B) and theaflavin 3,3'di-O-gallate (TF(3)) and thearubigins as novel mimics of insulin/IGF-1 action on mammalian FOXO1a, PEPCK and moreover we provide evidence that the effects on this pathway of the green tea constituent EGCG depend on its ability to be converted into these larger structures. With the exception of water, tea is the most popular beverage globally but despite this little is known about the biological availability of black tea polyphenols in vivo or the molecular target(s) mediating the effects presented here. Further investigation in these two areas might provide insight into how age-related metabolic disease may be deferred.
] facendo le stesse considerazioni.