title: Soy-derived phytoestrogens as preventive and acute neuroprotectors in experimental ischemic stroke: influence of rat strain.
abstract: The ability of a soy-based high-phytoestrogen diet (nutritional intervention) or genistein (pharmacological intervention), to limit ischemic brain damage in Wistar, Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats, has been assessed. As to the nutritional intervention, two groups from each strain received either a phytoestrogen-free (PE-0) or a high-phytoestrogen (PE-600) diet from weaning to adulthood. As to the pharmacological intervention, all animals were fed the standard soy-free AIN-93G diet and subsequently separated into two groups from each strain to receive either pure genistein (aglycone form, 1mg/kg/day intraperitoneal) or vehicle at 30 min reperfusion. After an episode of 90 min ischemia (intraluminal thread procedure) followed by 3 days reperfusion, cerebral infarct volume was measured. Arterial blood pressure (ABP) was significantly higher at the basal stage (just before ischemia) in SHR (140 ± 7 mmHg, n=17, p<0.05) than in Wistar (113 ± 4mmHg, n=23) and WKY (111 ± 6mmHg, n=14) rats. No significant differences were shown among the three stages (basal, ischemia, reperfusion) within each rat strain for both PE-0 and PE-600 diets. Wistar, but not WKY or SHR, rats fed the PE-600 diet showed significantly lower infarct volumes than their counterparts fed the PE-0 diet (30 ± 3% vs. 17 ± 3%, p<0.01). Genistein-treated Wistar, but not WKY or SHR, rats showed significantly lower infarct volumes than their vehicle-treated controls (27 ± 2% vs. 15 ± 2%, p<0.01). Our results demonstrate that: (1) the neuroprotective action of either chronic or acute exposure to soy isoflavones is strain-dependent, since it was shown in Wistar but not WKY or SHR rats; and (2) the soy-based diet does not prevent development of hypertension in SHR rats.
authors.affiliation: Centro de Investigación, Hospital Universitario La Fe, Ave. Campanar 21, 46009-Valencia, Spain; Departamento de Fisiología, Universidad de Valencia, Ave. Blasco Ibánez 15, 46010-Valencia, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Castelló-Ruiz
authors.forename: G
authors.initials: G
authors.lastname: Torregrosa
authors.forename: M C
authors.initials: MC
authors.lastname: Burguete
authors.forename: J B
authors.initials: JB
authors.lastname: Salom
authors.forename: J V
authors.initials: JV
authors.lastname: Gil
authors.forename: F J
authors.initials: FJ
authors.lastname: Miranda
authors.forename: T
authors.initials: T
authors.lastname: Jover-Mengual
authors.forename: V G
authors.initials: VG
authors.lastname: Marrachelli
authors.forename: E
authors.initials: E
authors.lastname: Alborch
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002545:Brain Ischemia / Q000178:diet therapy / Q000188:drug therapy / Q000628:therapy*; D002544:Cerebral Infarction / Q000517:prevention & control; D019833:Genistein / Q000494:pharmacology / Q000627:therapeutic use*; D018696:Neuroprotective Agents / Q000494:pharmacology / Q000627:therapeutic use*; D048789:Phytoestrogens / Q000494:pharmacology / Q000627:therapeutic use*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D051381:Rats; D011919:Rats, Inbred Strains; D015427:Reperfusion Injury / Q000517:prevention & control; D013025:Glycine max / Q000737:chemistry*; D020521:Stroke / Q000178:diet therapy / Q000188:drug therapy / Q000628:therapy*
chemical_list: D018696:Neuroprotective Agents; D048789:Phytoestrogens; D010936:Plant Extracts; D019833:Genistein