Genistein, a soy isoflavone, up-regulates expression of antioxidant genes: involvement of estrogen receptors, ERK1/2, and NFkappaB.
We have previously reported that estrogens up-regulate longevity-associated genes. As recent evidence has shown that estrogen replacement therapy is associated with an increased risk of cardiovascular disease, we have studied the effects of genistein, a soy isoflavone with a similar structure to estradiol, on the expression of antioxidant, longevity-related genes. MCF-7 cells (human mammary gland tumor cell line) were incubated for 48 h with 0.5 microM genistein, a concentration found in the plasma of populations consuming diets rich in soy protein. Peroxide levels were determined by fluorimetry, activation of extracellular-signal regulated kinase (ERK1/2), and nuclear factor kappaB (NFkappaB)-signaling pathways by Western blot analysis and ELISA, respectively, and mRNA expression of antioxidant genes by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Inhibition of basal peroxide levels in MCF-7 cells by genistein was prevented by pretreatment of cells with the estrogen receptor antagonist tamoxifen. Phosphorylation of extracellular regulated kinase (ERK)1/2 led to an activation of NFkappaB, as indicated by increased p50 subunit expression in nuclear extracts, and increased mRNA levels of the antioxidant enzyme manganese-superoxide dismutase (MnSOD). Inhibition of ERK1/2 abrogated genistein-mediated NFkappaB activation and elevated expression of MnSOD. Our molecular studies may provide a basis to determine the effects of genistein and other soy protein-derived products on longevity in both animals and the human population.
Borrás
Consuelo
C
Catholic University of Valencia, Valencia, Spain.
Gambini
Juan
J
Gómez-Cabrera
M Carmen
MC
Sastre
Juan
J
Pallardó
Federico V
FV
Mann
Giovanni E
GE
Viña
Jose
J
D000975:Antioxidants; D045744:Cell Line, Tumor; D005260:Female; D019833:Genistein / Q000494:pharmacology*; D006801:Humans; D007529:Isoflavones / Q000494:pharmacology*; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D016328:NF-kappa B; D011960:Receptors, Estrogen / Q000502:physiology; D015398:Signal Transduction; D013025:Glycine max / Q000737:chemistry; D013482:Superoxide Dismutase / Q000235:genetics*; D015854:Up-Regulation / Q000187:drug effects* / Q000235:genetics
D000975:Antioxidants; D007529:Isoflavones; D016328:NF-kappa B; D011960:Receptors, Estrogen; C065753:isoflavanone; D019833:Genistein; D013482:Superoxide Dismutase; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3