TY - JOUR
T1 - Effect of high soy diet on the cerebrovasculature and endothelial nitric oxide synthase in the ovariectomized rat
AU - Schreihofer, Derek A.
AU - Deutsch, Christian
AU - Lovekamp-Swan, Tara
AU - Sullivan, Jennifer C.
AU - Dorrance, Anne M.
N1 - Funding Information:
This work was supported by NIH R01AT001882 (DAS), NIH RO1 HL0077385 (AMD), and AHA0625626B (TLS), and AHA0840122N (AMD).
PY - 2010/5
Y1 - 2010/5
N2 - High soy (HS) diets are neuroprotective and promote vascular dilatation in the periphery. We hypothesized that an HS diet would promote vascular dilatation in the cerebrovasculature by mimicking estradiol's actions on the endothelial nitric oxide synthase (eNOS) system including increasing eNOS expression and decreasing caveolin-1 expression to increase nitric oxide (NO) production. Ovariectomized rats were fed HS or a soy-free diet (SF) ± low physiological estradiol (E2) for 4 weeks. Neither E2 nor HS altered middle cerebral artery (MCA) structure or vascular responses to acetylcholine, serotonin, or phenylephrine. Estradiol enhanced bradykinin-induced relaxation in an eNOS-dependent manner. Although E2 and HS increased eNOS mRNA expression in the brain and cerebrovasculature, they had no effect on eNOS protein expression or phosphorylation in the MCA. However, E2 decreased caveolin-1 protein in the MCA. In MCAs neither E2 nor HS altered estrogen receptor (ER) alpha expression, but E2 did reduce ER beta levels. These data suggest that HS diets have no effect on vascular NO production, and that E2 may modulate basal NO production by reducing the expression of caveolin-1, an allosteric inhibitor of NOS activity. However, the effects of E2 and HS on the cerebrovasculature are small and may not underlie their protective actions in pathological states.
AB - High soy (HS) diets are neuroprotective and promote vascular dilatation in the periphery. We hypothesized that an HS diet would promote vascular dilatation in the cerebrovasculature by mimicking estradiol's actions on the endothelial nitric oxide synthase (eNOS) system including increasing eNOS expression and decreasing caveolin-1 expression to increase nitric oxide (NO) production. Ovariectomized rats were fed HS or a soy-free diet (SF) ± low physiological estradiol (E2) for 4 weeks. Neither E2 nor HS altered middle cerebral artery (MCA) structure or vascular responses to acetylcholine, serotonin, or phenylephrine. Estradiol enhanced bradykinin-induced relaxation in an eNOS-dependent manner. Although E2 and HS increased eNOS mRNA expression in the brain and cerebrovasculature, they had no effect on eNOS protein expression or phosphorylation in the MCA. However, E2 decreased caveolin-1 protein in the MCA. In MCAs neither E2 nor HS altered estrogen receptor (ER) alpha expression, but E2 did reduce ER beta levels. These data suggest that HS diets have no effect on vascular NO production, and that E2 may modulate basal NO production by reducing the expression of caveolin-1, an allosteric inhibitor of NOS activity. However, the effects of E2 and HS on the cerebrovasculature are small and may not underlie their protective actions in pathological states.
KW - Estradiol
KW - Estrogen
KW - Middle cerebral artery
KW - Vasodilatation
KW - Vasoreactivity
UR - http://www.scopus.com/inward/record.url?scp=77950918082&partnerID=8YFLogxK
U2 - 10.1016/j.vph.2010.02.003
DO - 10.1016/j.vph.2010.02.003
M3 - Article
C2 - 20197113
AN - SCOPUS:77950918082
SN - 1537-1891
VL - 52
SP - 236
EP - 242
JO - Vascular Pharmacology
JF - Vascular Pharmacology
IS - 5-6
ER -