Enzymatically hydrolyzed lactotripeptides do not lower blood pressure in mildly hypertensive subjects.

BACKGROUND: Several placebo-controlled clinical studies suggest that products containing isoleucyl-prolyl-proline and valyl-prolyl-proline are able to lower blood pressure without adverse effects. The most efficient way of producing high concentrations of these lactotripeptides (LTPs) is enzymatic hydrolysis of dairy protein (casein) with the use of a mixture of several enzymes derived from the nongenetically modified organism Aspergillus oryzae, including proteases and peptidases. To date, no large studies of the blood pressure-lowering properties of enzymatically produced LTP (ELTP) powder in European populations have been published. OBJECTIVE: This study was performed to evaluate the hypothesis that consumption of ELTP in a yogurt beverage for 8 wk significantly lowers blood pressure. DESIGN: In this multicenter, double-blind, parallel, placebo-controlled trial, office blood pressure was evaluated in 275 Dutch hypertensive subjects. Blood pressures and body weight were measured on several days at baseline and at weeks 4 and 8 of the intervention between 2.5 and 3 h after intake of the test product. Twenty-four-h urine samples were collected at baseline and at the end of the intervention for urinalysis of sodium, potassium, creatinine, and microalbumin excretion. RESULTS: The results showed that 10.2 mg ELTP/d does not lead to a reduction in systolic blood pressure (P = 0.66) or diastolic blood pressure (P = 0.72) compared with placebo. CONCLUSION: This study showed no effect of an ELTP-enriched yogurt beverage on blood pressure in hypertensive subjects in a fairly large study.

Does the beneficial effect of HRT on endothelial function depend on lipid changes.

OBJECTIVES: To determine whether improvement in endothelial function of the brachial artery observed in women treated with hormone replacement therapy (HRT) may be explained by changes in lipid profile or blood pressure, information was used obtained in a single-centre, randomised, double blind, placebo-controlled trial. METHODS: Hundred-and-five healthy postmenopausal women, aged 50-65 years, were treated with 0.625 mg conjugated equine estrogens (CEE) combined with 2.5 mg medroxyprogesterone acetate (MPA) (CEE+MPA), 2.5 mg tibolone or placebo for 3 months. At baseline and after 3 months, endothelial function was assessed using flow-mediated dilatation (FMD) and nitro glycerine-mediated dilatation (NMD). Furthermore, lipids were measured. Multivariate linear regression analysis was applied to address the research question. RESULTS: Treatment with CEE+MPA resulted in an improvement in FMD of 2.0% (95% CI: -0.1; 4.1). CEE/MPA reduced total cholesterol with 13% (95% CI: -18%; -7%), LDL-cholesterol with 23% (95% CI: -30%; -15%) and lipoprotein(a) (Lp(a)) with 14% (95% CI: -26%; -2%). The magnitude of the relation of CEE/MPA with endothelial function was attenuated to from 2.0 to 1.6% when change in Lp(a) was taken into account. Adjustments for other lipids or blood pressure did not attenuate the association. CONCLUSIONS: The improvement in endothelial function in postmenopausal women treated with CEE+MPA appears to be partially mediated by change in Lp(a), and apparently not by changes in other lipids.

Arterial stiffness in postmenopausal women: determinants of pulse wave velocity.

OBJECTIVE To investigate the degree and potential cardiovascular determinants of arterial stiffness, assessed by aortic pulse wave velocity (PWV) measurements, and to relate arterial stiffness to absolute 10-12-year risks of stroke, coronary heart disease and death, as estimated by available risk functions, in postmenopausal women. METHOD We performed a cross-sectional study among 385 postmenopausal women, aged 50-74 years, sampled from the general population. Arterial stiffness was assessed non-invasively by measurement of aortic PWV using applanation tonometry. Information on health was obtained by medical history, registration of current medication, and physical examination. Height, weight, waist and hip circumferences, fasting glucose, total and high-density lipoprotein (HDL) cholesterol, triglycerides, resting blood pressure, and heart rate were measured. Three risk scores were used to estimate, for each individual, the absolute risk of stroke, coronary heart disease, and death within 10-12 years as a function of their cardiovascular risk factor profile. The relationship between PWV and these risk scores was subsequently determined. RESULTS Significant positive relationships with PWV were found for body mass index, fasting glucose, diabetes mellitus, and triglycerides in analyses adjusted for age, mean arterial blood pressure, and heart rate. Height and HDL cholesterol were inversely related to PWV. The risks of stroke, coronary heart disease, and death increased with increasing PWV in a linear graded manner. CONCLUSIONS This cross-sectional study among postmenopausal women provides evidence that most of the established cardiovascular risk factors are determinants of aortic PWV. Increased PWV marks an increased risk of stroke, coronary heart disease, and death within 10-12 years.