2.
Effect of an antioxidant drink on homocysteine levels in Alzheimer's patients.
Morillas-Ruiz, JM, Rubio-Perez, JM, Albaladejo, MD, Zafrilla, P, Parra, S, Vidal-Guevara, ML
Journal of the neurological sciences. 2010;(1-2):175-8
Abstract
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.
3.
The effect of polyphenols in olive oil on heart disease risk factors: a randomized trial.
Covas, MI, Nyyssönen, K, Poulsen, HE, Kaikkonen, J, Zunft, HJ, Kiesewetter, H, Gaddi, A, de la Torre, R, Mursu, J, Bäumler, H, et al
Annals of internal medicine. 2006;(5):333-41
Abstract
BACKGROUND Virgin olive oils are richer in phenolic content than refined olive oil. Small, randomized, crossover, controlled trials on the antioxidant effect of phenolic compounds from real-life daily doses of olive oil in humans have yielded conflicting results. Little information is available on the effect of the phenolic compounds of olive oil on plasma lipid levels. No international study with a large sample size has been done. OBJECTIVE To evaluate whether the phenolic content of olive oil further benefits plasma lipid levels and lipid oxidative damage compared with monounsaturated acid content. DESIGN Randomized, crossover, controlled trial. SETTING 6 research centers from 5 European countries. PARTICIPANTS 200 healthy male volunteers. MEASUREMENTS Glucose levels, plasma lipid levels, oxidative damage to lipid levels, and endogenous and exogenous antioxidants at baseline and before and after each intervention. INTERVENTION In a crossover study, participants were randomly assigned to 3 sequences of daily administration of 25 mL of 3 olive oils. Olive oils had low (2.7 mg/kg of olive oil), medium (164 mg/kg), or high (366 mg/kg) phenolic content but were otherwise similar. Intervention periods were 3 weeks preceded by 2-week washout periods. RESULTS A linear increase in high-density lipoprotein (HDL) cholesterol levels was observed for low-, medium-, and high-polyphenol olive oil: mean change, 0.025 mmol/L (95% CI, 0.003 to 0.05 mmol/L), 0.032 mmol/L (CI, 0.005 to 0.05 mmol/L), and 0.045 mmol/L (CI, 0.02 to 0.06 mmol/L), respectively. Total cholesterol-HDL cholesterol ratio decreased linearly with the phenolic content of the olive oil. Triglyceride levels decreased by an average of 0.05 mmol/L for all olive oils. Oxidative stress markers decreased linearly with increasing phenolic content. Mean changes for oxidized low-density lipoprotein levels were 1.21 U/L (CI, -0.8 to 3.6 U/L), -1.48 U/L (-3.6 to 0.6 U/L), and -3.21 U/L (-5.1 to -0.8 U/L) for the low-, medium-, and high-polyphenol olive oil, respectively. LIMITATIONS The olive oil may have interacted with other dietary components, participants' dietary intake was self-reported, and the intervention periods were short. CONCLUSIONS Olive oil is more than a monounsaturated fat. Its phenolic content can also provide benefits for plasma lipid levels and oxidative damage. International Standard Randomised Controlled Trial number: ISRCTN09220811.