Marco A. Delgado

Changes in arterial blood pressure in hypertensive rats caused by long-term intake of milk fermented by Enterococcus faecalis CECT 5728

We have evaluated the changes in arterial blood pressure caused in spontaneously hypertensive rats (SHR) by long-term intake of an Enterococcus faecalis CECT 5728-fermented milk with significant angiotensin-converting enzyme (ACE)-inhibitory activity. After being weaned, male 3-week-old SHR were randomized into five groups. Until the 20th week of life, rats in each group were given one of the following drinking fluids: tap water (negative control 1), a fermented milk without ACE-inhibitory activity (negative control 2), captopril (100 mg/kg) (positive control), the E. faecalis CECT 5728-fermented milk that had significant ACE-inhibitory activity, or Ca-enriched E. faecalis CECT 5728-fermented milk. Animals in the different groups were then given tap water as drinking fluid from the 20th to 25th week of life. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured weekly in the rats, from the 6th to 25th week of life, by the tail-cuff method. A definite decrease in SBP and DBP could be observed in the rats treated with captopril and also in the rats that received the E. faecalis CECT 5728-fermented milks. The greatest antihypertensive effect was observed when the pharmacological treatment was administered. The effect of the Ca-enriched fermented milk was slightly more accentuated and more constant than the effect of the E. faecalis CECT 5728-fermented milk that had not been enriched in Ca. SBP and DBP increased in the treated SHR when the corresponding antihypertensive treatment was removed. Fermentation of milk with E. faecalis CECT 5728 may therefore be a successful strategy to produce a functional food with antihypertensive activity.

Efficacy of a microencapsulated iron pyrophosphate-fortified fruit juice: a randomised, double-blind, placebo-controlled study in Spanish iron-deficient women.

Fe-deficiency anaemia is a worldwide health problem. We studied the influence of consuming an Fe-fortified fruit juice on Fe status in menstruating women. A randomised, double-blind, placebo-controlled study of 16 weeks of duration was performed. Subjects were randomised into two groups: the P group (n 58) or the F group (n 64), and consumed, as a supplement to their usual diet, 500 ml/d of a placebo fruit juice or an Fe-fortified fruit juice, respectively. The Fe-fortified fruit juice, containing microencapsulated iron pyrophosphate, provided 18 mg Fe/d (100 % of the RDA). At baseline and monthly, dietary intake, body weight and Fe parameters were determined: total erythrocytes, haematocrit, mean corpuscular volume (MCV), red blood cell distribution width (RDW), Hb, serum Fe, serum ferritin, serum transferrin, transferrin saturation, soluble transferrin receptor (sTfR) and zinc protoporphyrin (ZnPP). The fruit juice consumption involved increased intake of carbohydrates and vitamin C, and increased BMI within normal limits. Ferritin was higher in the F group after week 4 (P < 0·05) and became 80 % higher than in the P group after week 16 (P < 0·001), and transferrin decreased in the F group compared with the P group after week 4 (P < 0·001). RDW was higher at weeks 4 and 8 in the F group compared with the P group (P < 0·05). Transferrin saturation increased after week 8, and haematocrit, MCV and Hb increased after week 12, in the F group compared with the P group. Serum Fe did not change. sTfR and ZnPP decreased in the F group at week 16 (P < 0·05). Iron pyrophosphate-fortified fruit juice improves Fe status and may be used to prevent Fe-deficiency anaemia.

Dietary intake of green tea polyphenols regulates insulin sensitivity with an increase in AMP‐activated protein kinase α content and changes in mitochondrial respiratory complexes

SCOPE The intake of food rich in polyphenols is related to a lower incidence in almost all chronic degenerative diseases. However, relatively little is known about the molecular mechanisms involved in its antioxidant properties. The aim of this study was to determine whether the mechanism of action of polyphenols could be related to a modulation in energy uptake and metabolism, and further induced mitochondrial changes. METHODS AND RESULTS For this purpose, male C57BL6 mice were fed during 3 months with a tea-based beverage rich in polyphenols. Insulin sensitivity, tissue oxidative damage biomarkers, as well as energy-related signaling pathways were determined to evaluate its mechanism of action. As a result, a tissue- and protein-specific subtle reduction in oxidative damage was observed. Skeletal muscle showed mitochondrial changes in respiratory complexes and an increase in AMP-activated protein kinase α levels, suggesting reduced energy availability. These changes were also associated with adipose tissue cellular metabolism. This was confirmed by a decline in the potential of energy uptake, evidenced by a diminished intestinal and systemic absorption of carbohydrates together with an inhibition of insulin sensitivity. CONCLUSIONS Our results suggest that the mechanisms of action of green tea polyphenols may be related to their ability to modulate energy uptake leading to mitochondrial adaptations possibly responsible for the changes in protein oxidative damage.

Antioxidantes, atividade física e estresse oxidativo em mulheres idosas

OBJECTIVE: To verify the influence of dietary antioxidant supplementation in older women who regularly practice physical activities, on the occurrence of oxidative stress, physical health and risk of cardiovascular diseases (CVD). METHOD: Two groups (S and C) of women, with age ranging from 60 to 80 years old, were observed. Both groups took part in a physical activity program for 58 weeks, three times a week, for about 50 to 55 minutes each session. The diet of group S (n=36) was daily supplemented with 330 ml of a functional antioxidant beverage, FuncionaTM; Group C (n=32) ingested water and was used as Control. As oxidative stress indicators, the plasmatic concentrations of reduced (GSH) and oxidized (GSSG) glutathione were determined; the molar GSH/GSSG ratio was calculated, and the oxidative damage in lipids and proteins was evaluated. The physical and cardiovascular conditions were evaluated through routine anthropometric parameters (weight, stature and BMI) and blood pressure. RESULTS: Group C presented significant increases of oxidative stress, reduction in the blood pressure and in the indicators of cardiovascular risks. Group S presented significant reduction of the oxidative stress and increment of the cardiovascular gains. Significance concerning the ergogenic effects has not been identified. CONCLUSION: Our data suggest that regular exercise in older women can improve physical and cardiovascular conditions. Moreover, daily intake of functional antioxidant supplement can minimize harmful effects of the reactive oxygen species.