title: Inhibition by soya isoflavones of human polymorphonuclear leukocyte function: possible relevance for the beneficial effects of soya intake.
abstract: Lower CVD incidence is reported in Asian populations consuming soya-containing food. As polymorphonuclear leukocytes (PMN) are involved in the risk of CVD, we investigated the modulatory effect of soya isoflavones on several PMN functions and their molecular mechanisms in vitro. PMN, isolated from blood from healthy subjects, were tested upon activation with 1 microm- n-formyl-methyl-leucyl-phenylalanine (fMLP) for superoxide anion production (ferric cytochrome c reduction) and released elastase (chromogenic test). PMN homotypic aggregates stimulated by fMLP or P-selectin in dynamic conditions were detected by optical microscopy. PMN, mixed with thrombin-activated, washed platelets, formed cell aggregates, measured by flow cytometry. Phosphorylation of Pyk2, a focal adhesion kinase, was studied by immunoprecipitation and immunoblotting with specific antibodies. Genistein, daidzein and equol inhibited superoxide anion production (IC50 0.25 (sem 0.1), 21.0 (sem 4.2) and 13.0 (sem 2.8) microm, respectively); the release of elastase was prevented by genistein (IC50 63 (sem 17) microm). PMN homotypic aggregates, stimulated by fMLP, were significantly reduced (24 (sem 12) and 51 (sem 14) % of control) by 100 microm genistein and equol. P-selectin-induced aggregates were reduced to 19 (sem 6), 44 (sem 10) and 28 (sem 9) % of control by 100 microm genistein, daidzein and equol, respectively. Genistein, daidzein and equol also significantly reduced mixed platelet-PMN aggregates (IC50 4.0 (sem 0.9), 57 (sem 6) and 66 (sem 23) microm, respectively). In PMN challenged by fMLP or P-selectin, activation of Pyk2 was prevented by isoflavones. The cardioprotective effect of soya-containing food might be linked to reduction of PMN activation and PMN-platelet interaction, novel targets for the biological effects of soya isoflavones.
authors.affiliation: Laboratory of Vascular Biology and Pharmacology, Istituto di Ricerche Farmacologiche Mario Negri, Consorzio Mario Negri Sud, Santa Maria Imbaro, Chieti, Italy.
authors.forename: Serenella
authors.initials: S
authors.lastname: Rotondo
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Krauze-Brzósko
authors.forename: Stefano
authors.initials: S
authors.lastname: Manarini
authors.forename: Nicola
authors.initials: N
authors.lastname: Martelli
authors.forename: Romina
authors.initials: R
authors.lastname: Pecce
authors.forename: Virgilio
authors.initials: V
authors.lastname: Evangelista
authors.forename: Maria
authors.initials: M
authors.lastname: Benedetta Donati
authors.forename: Chiara
authors.initials: C
authors.lastname: Cerletti
mesh_terms: D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D060754:Equol; D051418:Focal Adhesion Kinase 2 / Q000378:metabolism; D019833:Genistein / Q000494:pharmacology; D006801:Humans; D007529:Isoflavones / Q000494:pharmacology*; D016177:Macrophage-1 Antigen / Q000378:metabolism; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects* / Q000502:physiology; D019007:P-Selectin / Q000494:pharmacology; D010196:Pancreatic Elastase / Q000378:metabolism; D010766:Phosphorylation; D010973:Platelet Adhesiveness / Q000187:drug effects; D013025:Glycine max / Q000737:chemistry*; D013481:Superoxides / Q000378:metabolism
chemical_list: C007610:4',7-dihydroxy-3,4-dihydroisoflavone; D007529:Isoflavones; D016177:Macrophage-1 Antigen; D019007:P-Selectin; D013481:Superoxides; D060754:Equol; D009240:N-Formylmethionine Leucyl-Phenylalanine; C004742:daidzein; D019833:Genistein; D051418:Focal Adhesion Kinase 2; D010196:Pancreatic Elastase