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Genomica nutrizionale e approccio sperimentale. Go et al., 2003. La metilazione dei dinucleotidi 5’CpG3’ nei promotori modula l’espressione dei geni . Mantenimento del pattern di metilazione durante la duplicazione del DNA . L’acetilazione degli istoni. Nutrienti, attività genica e tumore.
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Genomica nutrizionale e approccio sperimentale Go et al., 2003
La metilazione dei dinucleotidi 5’CpG3’ nei promotori modula l’espressione dei geni
Mantenimento del pattern di metilazione durante la duplicazione del DNA
Componenti nutrizionali bio-attivi Cancer prevention – the potential for diet to modulate molecular signalling Trends in Molecular Medicine, Manson, 2002
Depending on the circumstances, dietary compounds such as curcumin, epigallocatechin gallate (EGCG), resveratrol and indole-3-carbinol (I3C) can up- or down-regulate signalling to induce stress-response genes, or growth arrest and apoptosis Manson, 2002
Different chemopreventive agents can suppress the activity of IKK, PI3K and/or PKB, inhibit the translocation of NF-kB to the nucleus, or upregulate PTEN Manson, 2002
Chemopreventive agents, such as indole-3-carbinol and epigallocatechin gallate, can downregulate the expression or activity of CDKs and cyclins, and upregulate CDK inhibitors such as p21 and p27, thereby causing cell-cycle arrest in G1 . Manson, 2002
Induction of stress-response genes by chemopreventive chemicals Manson, 2002
Restrizione calorica Regime dietetico a basso contenuto calorico in assenza di sottonutrizione o malnutrizione Allungamento della sopravvivenza del 50% in lievito, nematodi, roditori e scimmie
Pathways metabolici modificati dalla restrizione calorica Koubova et al., 2003
Restrizione calorica e stress ossidativo Hyon Jeen Kim et al., 2002
Possibile meccanismo attraverso cui la CR migliora la funzionalità neuronale
Restrizione calorica e invecchiamento Barja, 2002
CR manipulates the membrane fatty acid components as an adaptive measure against age-related peroxidizability — an efficient and smart strategy to resist oxidative stress. Barja, 2002
Exercised CR animals are shown to have an additional extended mean life span of ~10% beyond their nonexercised CR counterparts. Suppression of microsomal production of reactive oxygen species by CR. AS, ad libitum-fed, sedentary; AE, ad libitum-fed, exercising; RS, CR, sedentary; RE, CR, exercising; DCF = 2'7'-dichlorodihydrofluorescin Yu et al., 2003
ARC (apoptosis repressor) levels in the brain of adult (12AD), old (26AD), and old caloric restricted (26CR) Fischer 344 male rats determined by Western blot analysis
Reduction of the incidence of tumors following reduction of food intake An even more remarkable example of CR’s ability to resist irradiation is shown in the work of Gross and Dreyfuss, who challenged mice with gamma irradiation to induce tumorigenesis. They not only show a clear-cut tumor suppression by CR (TABLE) but also that CR rats had a far better capability of resisting one of the most deleterious forms of stressors. Shelke et al., 2003