Effect of an antioxidant drink on homocysteine levels in Alzheimer's patients.

BACKGROUND: A large body of evidence supports a role of oxidative stress in Alzheimer disease (AD) and in cerebrovascular disease. Blood levels of homocysteine may be increased in AD and hyperhomocysteinemia may contribute to disease pathophysiology by vascular and direct neurotoxic mechanisms. Even in the absence of vitamin deficiency, plasma total homocysteine (tHcy) concentration may be influenced by administration of polyphenols. OBJECTIVE: To determine the effect of an antioxidant beverage rich in polyphenols on the plasmatic levels of tHcy in Alzheimer's patients. DESIGN, SETTING, AND PATIENTS: A multicenter, randomized, double-blind controlled clinical trial of polyphenols supplementation in 100 subjects (52 of control group, 24 AD patients in initial phase and 24 AD patients in moderate phase) (Mini-Mental State Examination scores between 14 and 26, inclusive). Fasting plasma concentrations of tHcy, folate and vitamin B(12) were measured before (Ti) and after (Tf) the ingestion of the beverage. The study was conducted at clinical research places of the Catholic University San Antonio and University Hospital Virgen de la Arrixaca of Murcia (Spain). INTERVENTION: Participants of the three groups were randomly assigned to 2 groups of the same size: 50% treated with antioxidant beverage rich in polyphenols and 50% treated with an identical placebo beverage. Subjects consumed 1 brick (200 mL/day) of antioxidant drink or placebo drink for 8 months. RESULTS: Higher tHcy levels were observed in the AD moderate phase patients (Ti:12.65±1.21 µmol/L) than in the AD initial phase patients (Ti:9.13±1.24 µmol/L) and in the control group (Ti:9.86±0.77 µmol/L). Lower folate levels were observed in the AD moderate phase patients (Ti:8.20±1.29 ng/mL) than in the AD initial phase patients (Ti:9.41±1.56 ng/mL) and in the control group (Ti:12.32±0.67 ng/mL). Antioxidant drink vs placebo drink attenuated the tHcy increase in the control group (Tf values of 11.74±0.45 vs 15.63±1.79 µmol/L) and AD patients, especially in the moderate phase (Tf: 10.49±0.73 vs 16.58±2.73 µmol/L). CONCLUSIONS: The regular ingestion of polyphenols contained in an antioxidant beverage may decrease tHcy plasmatic concentrations in Alzheimer's patients.

Effects of polyphenolic antioxidants on exercise-induced oxidative stress.

Polyphenols are of increasing interest to consumers and food manufacturers for several reasons. Commonly referred to as antioxidants (they are the most abundant antioxidants in our diets), they may prevent various oxidative stress-related diseases, such as cancer, cardiovascular disease, inflammation and others. Physical activity is known to induce oxidative stress in individuals after intensive exercise. In this study, the effect of the flavonoid contents (which are the most abundant polyphenols) was investigated, as the only antioxidant in a replacement drink designed for sportsmen on various oxidative stress biomarkers after two identical trials of sub-maximal aerobic exercise, in a group of 30 sportsmen. In one of the trials, the cyclists consumed the antioxidant supplement (with 2.3g polyphenols/trial), and in another they consumed a placebo. Blood samples were collected both at rest and after exercise immediately and 45 minutes (min) later, for measurements of plasmatic indices of oxidative stress: lipid oxidation (TBARS), total antioxidant status (TAS); protein oxidation (carbonyl groups, CO) and the lactate dehydrogenase (LDH) and creatine kinase (CK) enzymes for each trial. All values were adjusted for changes in plasma volume. No changes were detected in plasma TAS and LDH after exercise or after the polyphenolic supplement. CK and TBARS increased after exercise in both tests. However, in response to strenuous exercise, the polyphenol-supplemented test showed a smaller increase in plasma TBARS and CK than the placebo test. CO increased by 12% in response to the placebo test, whereas it decreased by 23% in the polyphenol-supplement test. This may indicate that the antioxidant supplement offered protection against exercise-induced oxidative stress.

Use of heme iron concentrate in the fortification of weaning foods.

The purpose of this study was to evaluate the technological feasibility of fortifying homogenized weaning food with a porcine heme concentrate. The stability of iron and the organoleptic qualities of two infant weaning foods (a commercial homogenized nonfortified weaning food, NFWF, and the same food fortified with 0.5% of porcine heme concentrate, FWF) were tested throughout 8 months of storage at room temperature and at 37 degrees C. Heme iron decreased with storage time; however, the proportion of this highly available iron was considerably higher in FWF than in NFWF. The addition of heme iron changed significantly the color of the weaning food measured instrumentally, although high temperatures and length of storage time, did not modify Lab, chroma, and hue angle values in both samples. Organoleptic attributes presented a marked stability even in NFWF stored at room temperature and 37 degrees C.