Low-Sodium DASH reduces oxidative stress and improves vascular function in salt-sensitive humans.
Salt induces oxidative stress in salt-sensitive (SS) animals and man. It is not known whether in SS subjects the low-sodium dietary approaches to stop hypertension (LS-DASH) reduces oxidative stress more than DASH, which is high in antioxidants. To assess the effects of DASH and LS-DASH on oxidative stress, 19 volunteers were studied after 3 weeks of a standardized usual low fruits and vegetables diet (ULFV), followed by 3 weeks on DASH (both diets approximately 120 mmol Na(+) per day), then 3 weeks on LS-DASH (60 mmol Na(+) per day). SS was defined as systolic blood pressure >or=5 mm Hg lower on LS-DASH than DASH. In SS subjects (N=9), systolic blood pressure was lower on LS-DASH (111.0+/-2.0 mm Hg) than DASH (118.0+/-2.2, P<0.01) and ULFV (122.3+/-2.7, P=0.002). In salt-resistant (SR) volunteers (N=10), systolic blood pressure was lower on DASH (113.0+/-1.6) than ULFV (119.0+/-1.8, P<0.05) but not LS-DASH (115.7+/-1.8). Urine F2-isoprostanes, a marker of oxidative stress, were lower in SS subjects on LS-DASH (1.69+/-0.24) than ULFV (3.09+/-0.50, P<0.05) and marginally lower than DASH (2.46+/-0.44, P<0.20). F2-isoprostanes were not different among the three diets in SR volunteers (2.18+/-0.29, 2.06+/-0.29, 2.27+/-0.53, respectively). Aortic augmentation index, a measure of vascular stiffness, was lower in SS subjects on LS-DASH than either DASH or ULFV, and lower on DASH than ULFV in SR volunteers. In SS but not SR subjects, LS-DASH is associated with lower values for F2-isoprostanes and the aortic augmentation index. The results suggest that LS-DASH decreases oxidative stress, improves vascular function and lowers blood pressure in SS but not SR volunteers.
Al-Solaiman
Y
Y
Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA.
Jesri
A
A
Zhao
Y
Y
Morrow
J D
JD
Egan
B M
BM
D000328:Adult; D000450:Aldosterone / Q000097:blood; D001011:Aorta / Q000502:physiology; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D004039:Diet, Sodium-Restricted; D004548:Elasticity; D004573:Electrolytes / Q000652:urine; D028441:F2-Isoprostanes / Q000652:urine; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000178:diet therapy* / Q000188:drug therapy*; D007328:Insulin / Q000097:blood; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects*; D010636:Phenols / Q000008:administration & dosage*; D010936:Plant Extracts / Q000008:administration & dosage*; D011189:Potassium Chloride / Q000008:administration & dosage*; D012083:Renin / Q000097:blood; D012965:Sodium Chloride / Q000008:administration & dosage; D014655:Vascular Resistance / Q000187:drug effects; D055815:Young Adult
D004573:Electrolytes; D028441:F2-Isoprostanes; D007328:Insulin; D008055:Lipids; D010636:Phenols; D010936:Plant Extracts; C501911:antioxidant biofactor AOB; D012965:Sodium Chloride; D000450:Aldosterone; D011189:Potassium Chloride; D012083:Renin