title: Isoflavone supplementation reduces DNA oxidative damage and increases O-β-N-acetyl-D-glucosaminidase activity in healthy women.
abstract: Phenolic compounds are believed to boost the human antioxidant defense system and health; therefore, the aim of this research was to investigate the hypothesis that soy isoflavones (IFs) provide antioxidant protection in healthy women by evaluating DNA resistance to oxidative damage and O-β-N-acetyl-D-glucosaminidase (OGA) activity. An IF supplement (80 mg/d) was given to 9 postmenopausal women and 13 young women for 6 months and then stopped up to the 14th month. The women were allowed to consume their normal diet. Blood samples were collected at the beginning of the study after 2, 4, and 6 months and then at the 8th and 14th months. Plasma concentrations of genistein and daidzein, total antioxidant capacity, plasma vitamin status, markers of oxidative stress (red blood cell membrane fluidity, activity of the red blood cell cytosolic enzyme OGA and lymphocyte DNA susceptibility to oxidative stress), and serum lipid profile were analyzed. Analysis of variance for repeated measures was used for statistical analysis. Plasma concentrations of IFs rose significantly during the supplementation period, and plasma total antioxidant capacity increased in young women; membrane fluidity and OGA activity increased, and DNA oxidative damage decreased (P < .05) at 4 months, then returned to the basal level. There was a significant inverse correlation between DNA damage and plasma IF concentrations (P < .01). The results indicated a positive effect of IF supplementation on oxidative stress in women, thus suggesting that the healthful action ascribed to soy consumption may be partially related to the antioxidant potential of IFs.
authors.affiliation: Department of Food Science and Microbiology (DISTAM), University of Milan, Via Celoria 2, 20133 Milan, Italy. daniela.erba@unimi.it
authors.forename: Daniela
authors.initials: D
authors.lastname: Erba
authors.forename: M Cristina
authors.initials: MC
authors.lastname: Casiraghi
authors.forename: Cristina
authors.initials: C
authors.lastname: Martinez-Conesa
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Goi
authors.forename: Luca
authors.initials: L
authors.lastname: Massaccesi
mesh_terms: D000118:Acetylglucosaminidase / Q000378:metabolism*; D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage; D015415:Biomarkers / Q000097:blood; D004249:DNA Damage / Q000187:drug effects*; D019587:Dietary Supplements; D005260:Female; D019833:Genistein / Q000008:administration & dosage / Q000097:blood*; D006801:Humans; D007529:Isoflavones / Q000008:administration & dosage / Q000097:blood*; D016014:Linear Models; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects*; D010636:Phenols / Q000008:administration & dosage; D017698:Postmenopause; D013025:Glycine max / Q000737:chemistry; D011795:Surveys and Questionnaires; D014815:Vitamins / Q000097:blood; D055815:Young Adult
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D007529:Isoflavones; D010636:Phenols; D014815:Vitamins; C004742:daidzein; D019833:Genistein; D000118:Acetylglucosaminidase