Biomedical subjects

Julio J Ochoa

Publications and source records attributed to Julio J Ochoa.

16 recordsLinked to original sources

PubMed2006

Coenzyme Q concentration and total antioxidant capacity of human milk at different stages of lactation in mothers of preterm and full-term infants.

Coenzyme Q10(CoQ10) in human milk at different stages of maturity in mothers of preterm and full-term infants and its relation to the total antioxidant capacity of milk is described for the first time. Thirty healthy breastfeeding women provided colostrum, transition-milk and mature-milk samples. Coenzyme Q, alpha-, gamma- and delta-tocopherol, fatty acids and the total antioxidant capacity of the milk were analyzed. Coenzyme Q10 was found at higher concentrations for colostrum (0.81+/-0.06 vs. 0.50+/-0.05 micromol/l) and transition milk (0.75+/-0.06 vs. 0.45+/-0.05 micromol/l) in the full-term vs. the preterm group (similar results were found for total antioxidant capacity). Concentrations of alpha- and gamma-tocopherol were higher in the full-term group and decreased with time. In conclusion, CoQ10 is present in breast milk, with higher concentration in mothers of full-term infants. CoQ10 in breast milk decreases through lactation in mothers delivering full-term infants. Also, CoQ10, alpha- and gamma-tocopherol concentration in human milk directly correlates with the antioxidant capacity of the milk.

Adult↗

PubMed2006

Age-related mitochondrial DNA deletion in rat liver depends on dietary fat unsaturation.

We fed male Wistar rats lifelong on virgin olive (rich in the monounsaturated oleic acid) or sunflower (rich in the polyunsaturated linoleic acid) oil-based diets. At 6 and 24 months, liver mitochondria were analyzed for a mitochondrial DNA (mtDNA) deletion, reactive oxygen species, antioxidants, and ultrastructural alterations. An aging-related increase in the relative amount of the deletion was observed for both dietary groups, being higher in animals fed sunflower oil. Oxidative stress was lower in virgin olive oil-fed animals. Aging led to higher superoxide dismutase, catalase, and glutathione peroxidase activities and increased alpha-tocopherol and coenzyme Q. Mitochondria from aged animals fed sunflower oil exhibited a lower number of cristae and a higher circularity. Results suggest that the age-related increase of the relative amount of deleted mtDNA depends on fat unsaturation. Moreover, the studied mtDNA deletion was correlated with mitochondrial oxidative stress and ultrastructural alterations.

Aging↗

PubMed2005

Life-long supplementation with a low dosage of coenzyme Q10 in the rat: effects on antioxidant status and DNA damage.

Life-long low-dosage supplementation of coenzyme Q(10) (CoQ(10)) is studied in relation to the antioxidant status and DNA damage. Thirty-two male rats were assigned into two experimental groups differing in the supplementation or not with 0.7 mg/kg/day of CoQ(10). Eight rats per group were killed at 6 and 24 months. Plasma retinol, alpha-tocopherol, coenzyme Q, total antioxidant capacity and fatty acids were analysed. DNA strand breaks were studied in peripheral blood lymphocytes. Aging and supplementation led to significantly higher values for CoQ homologues, retinol and alpha-tocopherol. No difference in total antioxidant capacity was detected at 6 months but significantly lower values were found in aged control animals. Similar DNA strand breaks levels were found at 6 months. Aging led to significantly higher DNA strand breaks levels in both groups but animals supplemented with CoQ(10) led to a significantly lower increase in that marker. Aged rats showed significantly higher polyunsaturated fatty acids. This study demonstrates that lifelong intake of a low dosage of CoQ(10) enhances plasma levels of CoQ(9), CoQ(10), alpha-tocopherol and retinol. In addition, CoQ(10) supplementation attenuates the age-related fall in total antioxidant capacity of plasma and the increase in DNA damage in peripheral blood lymphocytes.

Aging↗

PubMed2005

Coenzyme Q10 protects from aging-related oxidative stress and improves mitochondrial function in heart of rats fed a polyunsaturated fatty acid (PUFA)-rich diet.

Coenzyme Q(10) supplementation on age-related changes in oxidative stress and function of heart mitochondria in rats fed a polyunsaturated fatty acid (PUFA)-rich diet was investigated. Two groups of rats were fed for 24 months on a PUFA-rich diet, differing in supplementation or not with coenzyme Q(10). Animals were killed at 6, 12, or 24 months. Fatty-acid profile, hydroperoxides, alpha-tocopherol, coenzyme Q, catalase and glutathione peroxidase activities, and cytochromes a+a(3), b, c+c(1) and cytochrome c oxidase activity were measured. Coenzyme Q(10)-supplemented animals showed lower hydroperoxide levels; higher content and/or activity of alpha-tocopherol, coenzyme Q, and catalase; and a slightly lower decrease in mitochondrial function. According to that, previously reported positive effects of coenzyme Q supplementation on the life span of rats fed a PUFA-rich diet might be a consequence, at least in part, of a lower oxidative stress level and perhaps, to a minor extent, of a smaller decrease in mitochondrial function.

Aging↗

PubMed2004

Conjugated linoleic acids (CLAs) decrease prostate cancer cell proliferation: different molecular mechanisms for cis-9, trans-11 and trans-10, cis-12 isomers.

The aims of this study were to examine the anti-proliferative effects of different concentrations of a commercial preparation of conjugated linoleic acids (CLA) mixture of isomers [cis-9, trans-11 CLA (c9,t11 CLA): trans-10, cis-12 CLA (50:50)] and their constituent isomers on PC-3, a human prostatic carcinoma cell line, and to study their effects on gene expression (mRNA and protein levels) of different enzymes and oncoproteins involved in oncogenesis and progression of prostate cancer. This includes pathways for arachidonic acid metabolism [cyclooxygenase 1 (COX-1), 2 (COX-2) and 5-lipoxygenase (5-LOX)], apoptosis (bcl-2) and cell cycle control (p21(WAF/Cip1)). Our results indicate a significant decrease in PC-3 proliferation elicited by CLA, although with high variability between isomers. The trans-10, cis-12 CLA was the most effective isomer (55% inhibition). This isomer was also able to decrease bcl-2 gene expression and to increase p21(WAF1/Cip1) mRNA levels (60% increase at highest concentration). In contrast, cis-9, trans-11 had no effect on these proteins but had a clear effect on 5-LOX expression and to a lesser degree on COX-2 protein level isomers. In conclusion, the anti-proliferative effects on PC-3 of CLA mixture and their constituent isomers are not equivalent, due to the different pathways involved for individual isomers. Trans-10, cis-12 seems to work preferentially through modulation of apoptosis and cell cycle control, while c9,t11 CLA isomer affects arachidonic acid metabolism.

Arachidonate 5-Lipoxygenase↗

PubMed2004

Olive oil and modulation of cell signaling in disease prevention.

Epidemiological studies show that populations consuming a predominantly plant-based Mediterranean-style diet exhibit lower incidences of chronic diseases than those eating a northern European or North American diet. This observation has been attributed to the greater consumption of fruits and vegetables and the lower consumption of animal products, particularly fat. Although total fat intake in Mediterranean populations can be higher than in other regions (ca. 40% of calories), the greater proportion is derived from olive oil and not animals. Increased olive oil consumption is implicated in a reduction in cardiovascular disease, rheumatoid arthritis, and, to a lesser extent, a variety of cancers. Olive oil intake also has been shown to modulate immune function, particularly the inflammatory processes associated with the immune system. Olive oil is a nonoxidative dietary component, and the attenuation of the inflammatory process it elicits could explain its beneficial effects on disease risk since oxidative and inflammatory stresses appear to be underlying factors in the etiology of these diseases in man. The antioxidant effects of olive oil are probably due to a combination of its high oleic acid content (low oxidation potential compared with linoleic acid) and its content of a variety of plant antioxidants, particularly oleuropein, hydroxytyrosol, and tyrosol. It is also possible that the high oleic acid content and a proportionate reduction in linoleic acid intake would allow a greater conversion of alpha-linolenic acid (18:3n-3) to longer-chain n-3 PUFA, which have characteristic health benefits. Adoption of a Mediterranean diet could confer health benefits in high-risk populations.

Arthritis, Rheumatoid↗

PubMed2004

Coenzyme Q supplementation protects from age-related DNA double-strand breaks and increases lifespan in rats fed on a PUFA-rich diet.

This study investigates the usefulness of a long-term supplementation with coenzyme Q(10) in rats from the point of view of lifespan, DNA double-strand breaks and to assess whether this supplementation might attenuate oxidative alterations related to PUFA-rich diets, which would allow to preserve beneficial aspects of PUFA on health avoiding their deleterious aspects. Supplemented animals showed higher concentration of coenzyme Q(10) in liver mitochondria, lower levels of DNA double-strand breaks in peripheral blood lymphocytes. Animals supplemented on coenzyme Q reached a significantly higher mean life span (11,7% higher, i.e. 2,5 months) and a significantly higher maximum life span (24% higher, i.e. 6 months) than non-supplemented animals. These results suggest that a long-term supplementation with a small dosage of coenzyme Q(10) might represent a good anti-aging therapy in rats fed on a PUFA-based diet.

Aging↗

PubMed2004

Dietary fat type (virgin olive vs. sunflower oils) affects age-related changes in DNA double-strand-breaks, antioxidant capacity and blood lipids in rats.

This study was designed to investigate the possible effect on DNA double-strand breaks, antioxidant capacity and blood lipids of feeding rats lifelong with two different dietary fat sources: virgin olive oil (rich in the monounsaturated oleic acid) or sunflower oil (rich in the polyunsaturated linoleic acid). No changes in mean or maximal lifespan were observed. Overall, aging led to increased levels of plasma cholesterol, triglycerides, phospholipids, total lipids, polyunsaturated fatty acids and DNA double-strand breaks. All these parameters were higher in animals fed on sunflower oil diet. Aging diminished total antioxidant capacity with both diets, but in a lower extension for virgin olive oil diet. A very good inverse correlation (r= -0.715; P < 0.01, for sunflower oil group and r= -0.535; P < 0.01 for virgin olive oil group) between DNA damage and total antioxidant capacity was found. These results allow to conclude that dietary fat type should be considered in studies on aging, since the intake of oils with different polyunsaturation levels directly modulates total antioxidant capacity of plasma, DNA damage to peripheral blood lymphocytes and lead to important changes at the lipid metabolism level. In the present study best results were found after intake of virgin olive oil, which suggest the possible use of that edible oil to provide a healthier aging.

Aging↗

PubMed2003

Oxidative stress in patients undergoing cardiac surgery: comparative study of revascularization and valve replacement procedures.

OBJECTIVE: The aim of this study was to evaluate the time course of oxidative stress markers in plasma and erythrocyte from patients undergoing open heart surgery with cardiopulmonary bypass (CPB) and to examine whether the type of surgical technique used (valve replacement or coronary revascularization) produces any differences in these makers. PATIENTS AND METHODS: Twenty-two patients undergoing cardiac surgery with CPB were divided in 2 groups (valve replacement or coronary revascularization). We took 5 blood samples at different times during cardiac surgery and analyzed thiobarbituric acid reactive substances (TBARS), alpha-tocopherol, coenzyme Q, and retinol in plasma and TBARS (baseline levels and induced by Fe(2+)-ascorbate oxidation), alpha-tocopherol, coenzyme Q and catalase, superoxide dismutase, and glutathione peroxidase activity in erythrocyte. RESULTS: Plasma alpha-tocopherol content decreased after starting CPB in both groups. In contrast, in erythrocytes there was an increase in the activity or concentration of all of the antioxidants. Erythrocyte TBARS contents, both baseline levels and induced levels, were higher in coronary revascularization group. CONCLUSION: Although both groups suffered an increase in oxidative stress after CPB, this increase was higher in coronary revascularization group and therefore the possibility of post-CPB complications could be more severe in this group. As the groups followed a different pattern of antioxidant response, a different therapeutic approach may be required for each.

Biomarkers↗

PubMed2003

Dietary fat (virgin olive oil or sunflower oil) and physical training interactions on blood lipids in the rat.

OBJECTIVE: We investigated whether the intake of virgin olive oil or sunflower oil and performance of physical exercise (at different states) affect plasma levels of triacylglycerols, total cholesterol, and fatty acid profile in rats. METHODS: The study was carried out with six groups of male rats subjected for 8 wk to a diet based on virgin olive oil (three groups) or sunflower oil (three groups) as dietary fat. One group for each diet acted as sedentary control; the other two groups ran in a treadmill for 8 wk at 65% of the maximum oxygen consumption. One group for each diet was killed 24 h after the last bout of exercise and the other was killed immediately after the exercise performance. Triacylglycerols, total cholesterol, and fatty acid profile were analyzed in plasma. Analysis of variance was used to test differences among groups. RESULTS: Animals fed on virgin olive oil had lower triacylglycerol and cholesterol values. Physical exercise reduced these parameters with both dietary treatments. Fatty acid profile showed higher monounsaturated fatty acid proportion in virgin olive fed oil animals and a higher omega-6 polyunsaturated fatty acid proportion in sunflower oil fed animals. Physical exercise reduced the levels of monounsaturated fatty acids with both diets and increased the proportions of omega-3 polyunsaturated fatty acids. CONCLUSIONS: Results from the present study supported the idea that physical exercise and the intake of virgin olive oil are very good ways of reducing plasma triacylglycerols and cholesterol, which is desirable in many pathologic situations. Concerning findings on fatty acid profile, we had results similar to those of other investigators regarding the effect of different sources of dietary fat on plasma. The most interesting results came from the effect of physical exercise, with significant increases in the levels of omega-3 polyunsaturated fatty acids, which may contribute to the antithrombotic state and lower production of proinflammatory prostanoids attributed to physical exercise.

Animals↗

PubMed2003

Aging-related oxidative stress depends on dietary lipid source in rat postmitotic tissues.

We investigate mitochondrial-lipid peroxidation of mitotic (liver) and postmitotic (heart and skeletal muscle) tissues of rats fed lifelong on two different lipid sources: virgin olive oil (monounsaturated fatty acids) and sunflower oil (n - 6 polyunsaturated fatty acids). Two groups of 80 rats each were fed over 24 months on a diet differing in the lipid source (virgin olive oil or sunflower oil). Twenty rats per group were killed at 6, 12, 18, and 24 months; liver, heart, and skeletal muscle mitochondria were isolated and the lipid profile, hydroperoxides, vitamin E, and ubiquinone as well as catalase activity measured. Lipid peroxidation was higher in postmitotic tissues, and sunflower oil led to a higher degree of polyunsaturation and peroxidation. The levels of alpha-tocopherol adapted to oxidative stress and preferentially accumulated during aging in heart and skeletal muscle. In conclusion, the type of dietary fat should be considered in studies on aging, since oxidative stress is directly modulated by this factor. This study confirms that postmitotic tissues are more prone to oxidative stress during aging and proposes a hypothesis to explain this phenomenon.

Aging↗

PubMed2003

Melatonin protects against lipid peroxidation and membrane rigidity in erythrocytes from patients undergoing cardiopulmonary bypass surgery.

The first aim of this study was to test whether there are changes in erythrocyte lipid peroxidation products and membrane fluidity during cardiac surgery involving cardiopulmonary bypass. Secondly, in vitro tests were performed to examine whether melatonin alters induced lipid peroxidation and reduced membrane fluidity in erythrocytes from these patients. Fifteen patients undergoing cardiac surgery involving cardiopulmonary bypass (CPB) were selected. Five blood samples were taken at different times during surgery for analysis of thiobarbituric acid reactive substances (TBARS) content and membrane fluidity of the erythrocytes. TBARS are an index of the level of lipid peroxidation. The results revealed an increase in TBARS levels and a parallel decrease in erythrocyte membrane fluidity (increased membrane rigidity) after the onset of CPB with respect to the reference sample. Likewise, in vitro induction of lipid peroxidation in the erythrocyte samples from CPB patients followed a similar pattern. The changes in TBARS levels and membrane fluidity were suppressed by pre-incubation of erythrocytes with melatonin prior to the induction (by 70 microm Fe2+ + 250 microm ascorbate) of lipid peroxidation in a concentration-dependent manner. The results constitute a persuasive argument for the use of melatonin for preventive and therapeutic purposes during CPB.

Antioxidants↗

PubMed2003

Oxidative stress is evident in erythrocytes as well as plasma in patients undergoing heart surgery involving cardiopulmonary bypass.

OBJECTIVE: The aim of this study was to analyse the level and progression of oxidative stress, in both plasma and erythrocytes, during heart surgery involving cardiopulmonary bypass. MATERIALS AND METHODS: Twenty two patients undergoing cardiac surgery and considered to present a high/severe level of surgical risk were selected. We took five blood samples at different times during the cardiac surgery and analysed TBARS, alpha-tocopherol, coenzyme Q and retinol in plasma and TBARS (baseline levels and induced by Fe2+-ascorbate oxidation), alpha-tocopherol, coenzyme Q and catalase, superoxide dismutase and gluthatione peroxidase activity in erythrocytes. RESULTS: Plasma results shown a decrease in both alpha-tocopherol and retinol concentration after starting CPB with respect to the reference level (13.6 +/- 1.5 nmol ml(-1) vs. 22.0 +/- 3.0 nmol ml(-1) and 1.2 +/- 0.1nmol ml(-1) vs. 1.8 +/- 0.2 nmol ml(-1), respectively (p < 0.05)). In comparison, in erythrocytes, all antioxidants, both enzymatic and non-enzymatic, increased in activity or concentration after starting CPB. Erythrocyte TBARS, both baseline levels and induced levels, followed a similar pattern, with an increase after starting CPB with respect to the reference level (3.9 +/- 0.6 nmol mg(-1) of protein vs. 2.3 +/- 0.2 nmol mg(-1) of protein and 10.6 +/- 0.8 nmol mg(-1) of protein vs. 6.7+/- 0.6 nmol mg(-1) of protein, respectively (p < 0.05)). CONCLUSION: These results reveal an increase in oxidative stress after CPB, both in plasma and erythrocytes, and although the organism is capable of attenuating this stress by means of various antioxidative defence mechanisms, there is an increased possibility of post-CPB complications and thus of mortality.

Cardiopulmonary Bypass↗

PubMed2003

Oxidative stress in erythrocytes from premature and full-term infants during their first 72 h of life.

OBJECTIVE: The aim of this study was to evaluate the extent of lipid peroxidation and the response of the enzymatic and non-enzymatic antioxidant defence system in erythrocytes from full-term and premature infants at birth, after 3 and after 72 h of life. STUDY DESIGN: Twenty infants were selected and divided in two groups according to their gestational age. Blood samples were taken at birth, at 3 and at 72 h of life, erythrocytes were isolated and the following parameters were measured: fatty-acid profile, coenzyme Q, alpha-tocopherol, hydroperoxides and the activity of the antioxidant enzymes catalase, superoxide dismutase (SOD) and cytosolic glutathione peroxidase (cGPx). RESULTS: For the three studied periods, several differences between full-term and premature infants were found. Premature children showed a higher concentration of hydroperoxides, a lower level of alpha-tocopherol and lower SOD and cGPx activity (except for cGPx at birth). Moreover, n-3 polyunsaturated fatty-acids percentages (essential for good neonatal development) were higher in full term children throughout all the study. CONCLUSION: Results suggest a strong imbalance between oxidants and antioxidants in premature infants during their first 72 h of life, a situation which could lead to several pathologies. Therefore, further research is needed, including possible nutritional intervention (with antioxidant therapy, supplementation of essential fatty acids and other dietary constituents) before and after birth.

Antioxidants↗

PubMed2002

Dietary oils high in oleic acid but with different unsaponifiable fraction contents have different effects in fatty acid composition and peroxidation in rabbit LDL.

OBJECTIVE: We investigated the influence of different edible oils high in oleic acid but with different unsaponifiable fractions on the fatty acid composition and lipid peroxidation in plasma and low-density lipoprotein (LDL) in rabbits. METHODS: Thirty-two rabbits were randomly assigned to four groups of eight animals. For 8 wk each group was fed a semisynthetic isoenergetic diet that differed by lipid source (Picual virgin olive oil, Picual virgin olive oil that had been subjected to an exhaustive process of washing, Arbequina virgin olive oil, and sunflower oil high in oleic acid). We analyzed the fatty acid profile, thiobarbituric acid reactive substances, alpha-tocopherol, coenzyme Q, and retinol in plasma and the fatty acid profile, hydroperoxides, alpha-tocopherol, and coenzyme Q in LDL. RESULTS: The two varieties of virgin olive oil behaved differently from the high-oleic sunflower oil, and the effect of the different ratios of oleic acid to linoleic acid in the lipid sources on fatty acid composition in plasma and LDL was significant. With regard to oxidative stress, LDL in the group that ingested the lipid sources with the greatest amount of phenolic compounds showed the highest level of antioxidants (alpha-tocopherol and coenzyme Q; P < 0.05) and the lowest susceptibility to lipid peroxidation (P < 0.05). CONCLUSION: This study provides evidence in vivo of the considerable antioxidant capacity of the phenolic fraction of virgin olive oil in rabbit LDL and the important role that this unsaponifiable fraction can play in the overall antioxidant benefit attributed to these oils. However, these effects depend on the phenolic content of the oil.

Animals↗

PubMed2002

Ageing-related tissue-specific alterations in mitochondrial composition and function are modulated by dietary fat type in the rat.

This study investigated the way in which feeding rats with two fat sources (olive or sunflower oils) affected electron-transport components and function of mitotic (liver) and postmitotic (heart and skeletal muscle) tissues during ageing. Rats adapted the mitochondrial-membrane-lipid profile to dietary fat throughout the study, suggesting that the benefits to eat either of the two fats might be maintained lifelong. Liver was more resistant to dietary changes and ageing than heart and skeletal muscle, which showed higher levels of coenzyme Q, cytochrome b, and cytochrome a + a3 with ageing and lower cytochrome c oxidase and complex IV turnover. Dietary fat differentially modulated the response of tissues during ageing, with sunflower oil leading to the highest levels of coenzyme Q and cytochromes b and a + a3. Since high levels of cytochrome b have been related to increased age, it could be hypothesized that olive oil could lead to less aged mitochondria.

Aging↗