nutritional supplements and nitric oxide bioactivity

Conditions: Nitric Oxide; Vascular Function; L-Arginine; Nitrate / Nitrite; Postprandial Metabolism

Summary: obese people have a disturbed postprandial metabolism and thereby a decreased postprandial vascular function. nitric oxide plays an important role in the postprandial vascular function. multiple studies already focused on various nutritional compounds to improve the postprandial vascular function by increasing the nitric oxide bioactivity. however, the vast majority of the trials has been performed with relatively high doses of the individual components, which are problematic to convert into daily food measures, thereby preventing translation of these findings. well-designed trails studying the effect of feasible amounts of nutritional supplements on the bioactivity of nitric oxide and vascular function are missing.


Eligibility criteria:
inclusion criteria: * men * aged between 40-70 years * waist circumference ≥ 102 * fasting plasma glucose \< 7.0 mmol/l * fasting serum total cholesterol \< 8.0 mmol/l * stable body weight (weight gain or loss \< 3 kg in the past three months) * willingness to give up being a blood donor from 8 weeks before the start of the study, during the study and for 4 weeks after completion of the study * no difficult venipuncture as evidenced during the screening visit * no current smoker * no diabetic patients * no familial hypercholesterolemia * no abuse of drugs * no more than 3 alcoholic consumptions per day * no use of medication known to treat blood pressure, lipid or glucose metabolism * no use of an investigational product within another biomedical intervention trial within the previous 1-month * no severe medical conditions that might interfere with the study, such as epilepsy, asthma, kidney failure or renal insufficiency, chronic obstructive pulmonary disease, inflammatory bowel diseases, auto inflammatory diseases and rheumatoid arthritis * no active cardiovascular disease like congestive heart failure or cardiovascular event, such as an acute myocardial infarction or cerebrovascular accident * willingness to give up the use of antibacterial mouth wash or antibacterial toothpaste, chewing-gum and tongue- scraping on the morning of each experimental test day exclusion criteria: * women * fasting plasma glucose ≥ 7.0 mmol/l * fasting serum total cholesterol ≥ 8.0 mmol/l * current smoker, or smoking cessation \<12 months * diabetic patients * familial hypercholesterolemia * abuse of drugs * more than 3 alcoholic consumptions per day * unstable body weight (weight gain or loss \> 3 kg in the past three months) * use medication known to treat blood pressure, lipid or glucose metabolism * use of an investigational product within another biomedical intervention trial within the previous 1-month * severe medical conditions that might interfere with the study, such as epilepsy, asthma, kidney failure or renal insufficiency, chronic obstructive pulmonary disease, inflammatory bowel diseases, auto inflammatory diseases and rheumatoid arthritis * active cardiovascular disease like congestive heart failure or cardiovascular event, such as an acute myocardial infarction or cerebrovascular accident * not willing to give up being a blood donor from 8 weeks before the start of the study, during the study or for 4 weeks after completion of the study * not or difficult to venipuncture as evidenced during the screening visit