Biomedical subjects

J Mataix

Publications and source records attributed to J Mataix.

At least 19 recordsLinked to original sources

PubMed2003

Vitamins B6 and B12 and folate status in an adult Mediterranean population.

OBJECTIVE: To assess the nutritional status for vitamins B(6) and B(12) and folate in an adult Mediterranean population, in order to identify patterns of intake, groups at risk for deficiency, and factors that might influence this risk. DESIGN: A cross-sectional epidemiological survey. SETTING: Andalusia, a western Mediterranean region in southern Spain. SUBJECTS: The study was carried out with a random sample of 3528 subjects (1813 men, 1715 women) who were between 25 and 60 y of age. Blood samples were obtained for biochemical assays in a random subsample of 384 subjects (183 men, 201 women). INTERVENTIONS: Food consumption was assessed by 48-h recall. Vitamin B(6) was measured as alpha erythrocyte aspartate aminotransferase activation coefficient (alphaEAST); vitamin B(12) and folate concentrations were measured in plasma. RESULTS: Energy and vitamin intakes were significantly higher in men than in women. In men, intakes were below two-thirds of the RDA in 10.8, 2.9 and 22.6% for B(6), B(12) and folate, respectively. The corresponding figures in women were 16.7, 5.1 and 23.5% for vitamins B(6), B(12) and folate. Age, place of residence and educational level, alcohol use and smoking were also associated with differences in the intake of these nutrients. Biochemical analyses showed that vitamins B(6), B(12) and folate status was acceptable in 75.7, 89.1 and 57.6% of the population, respectively. Plasma concentration of folate was significantly higher in women. CONCLUSION: Our results provide a precise estimate of the nutritional status for vitamins B(6), B(12) and folate in the adult population of southern Spain. Factors such as age, place of residence, level of education and smoking can increase the risk of inadequate intake of some nutrients. However, these factors did not affect biochemical indexes of nutritional status in the present study. SPONSORSHIP: Dirección General de Salud Pública and the Health Council of the Andalusian Regional Government.

Adult↗

PubMed2003

Assessment of thiamin (vitamin B1) and riboflavin (vitamin B2) status in an adult Mediterranean population.

The aim of the present study was to assess the nutritional status for thiamin (vitamin B1) and riboflavin (vitamin B2) in an adult Mediterranean population, in order to identify patterns of intake, groups at risk for deficiency and factors that might influence this risk. A cross-sectional survey was carried out in Andalusia, a western Mediterranean region in southern Spain. Nutrient intakes were studied in a random sample of 3390 subjects (1746 men, 1644 women) who were between 25 and 60 years of age. Blood samples were obtained for biochemical assays in a random subsample of 372 subjects (181 men, 191 women). Food consumption was assessed by 48 h recall. Vitamin B1 and B2 were measured as erythrocyte transketolase and as erythrocyte glutathione reductase activation coefficients, respectively. Energy and vitamin intakes were significantly higher in men than in women. Intakes were below two-thirds of the recommended dietary allowance for vitamin B1 in 7.80 % of the men and 4.50 % of the woman, and were below this level for vitamin B2 in 18.00 % of the men and 11.70 % of the women. Age, educational level, alcohol use and smoking were also associated with differences in the intake of these nutrients. Biochemical analyses showed that vitamin B1 and B2 status was deficient in 6.40 and 5.30 % of the population, respectively. Although factors such as gender, age, level of education, drinking and smoking can have an effect on the risk of inadequate intake of these nutrients, these factors did not affect biochemical indices of nutritional status in the present study.

Adult↗

PubMed2001

Dietary oils high in oleic acid, but with different non-glyceride contents, have different effects on lipid profiles and peroxidation in rabbit hepatic mitochondria.

The influence on the lipid profile and lipid peroxidation in rabbit-liver mitochondria exerted by different edible oils high in oleic acid but different non-glyceride phenolic fractions was studied. High-phenolic virgin olive oil from the variety "Picual", the same oil submitted to an exhaustive process of washing to eliminate the phenolic fraction without altering the lipid profile and high-oleic sunflower oil (poor in phenolic compounds) were added to rabbit diets. The results reveal the importance of the different oleic: linoleic ratio of the lipid sources on the lipid profile of mitochondrial membranes. This is highlighted by the greater proportion of saturated fatty acids and the lower content in oleic acid (p < 0.05) shown by the rabbits fed on high-oleic sunflower oil. The group fed on the fat rich in phenolics exhibited the highest level of antioxidants (alpha-tocopherol, ubiquinone 10) and the highest activity of glutathione peroxidase as well as the lowest content in hydroperoxides and TBARS. The study provides evidences in vivo about the considerable antioxidant capacity of the phenolic fraction of virgin olive oil in rabbit-liver mitochondria and the important role that this non-glyceride fraction can play in the overall antioxidant benefits attributed to this oil.

Journal Article↗

PubMed2001

Dietary fat type and regular exercise affect mitochondrial composition and function depending on specific tissue in the rat.

Physical exercise and fatty acids have been studied in relation to mitochondrial composition and function in rat liver, heart, and skeletal muscle. Male rats were divided into two groups according to dietary fat type (virgin olive and sunflower oils). One-half of the animals from each group were subjected to a submaximal exercise for 8 weeks; the other half acted as sedentary controls. Coenzyme Q, cytochromes b, c + c1, a + a3 concentrations, and the activity of cytochrome c oxidase were determined. Regular exercise increased (P < 0.05) the concentration of the above-mentioned elements and the activity of the cytochrome c oxidase by roughly 50% in liver and skeletal muscle. In contrast, physical exercise decreased (P < 0.05) cytochrome c oxidase activity in the heart (in micromol/min/g, from 8.4+/-0.1 to 4.9+/-0.1 in virgin olive oil group and from 9.7+/-0.1 to 6.7+/-0.2 in sunflower oil animals). Dietary fat type raised the levels of coenzyme Q, cytochromes, and cytochrome c oxidase activity in skeletal muscle (P < 0.05) among the rats fed sunflower oil. In conclusion, dietary fat type, regular exercise, and the specific tissue modulate composition and function of rat mitochondria.

Animals↗

PubMed2001

Risk of inadequate intakes of vitamins A, B1, B6, C, E, folate, iron and calcium in the Spanish population aged 4 to 18.

A meta-analysis of the most representative Spanish nutrition studies was carried out to identify inadequate intakes of vitamins, A, B1, B6, C, E, folate, iron, and calcium in children aged 4 to 18. Information on vegetable, fruit and fruit juice/beverage intake was also solicited. Data drawn from the selected studies yielded a total of 6540 children and adolescents in eight geographical areas. The sample was stratified by age (children: 4 to 14 years old and adolescents: 13-18 years old) and sex. Inadequate intakes (below two-thirds of the recommended values) were notable in children for vitamin E, vitamin C, and vitamin A and in girls, iron. In adolescents, low intakes were especially marked for vitamin E and vitamin A, and in girls, calcium, folate, and iron. Adolescents consumed more vegetables, fruit juice, and fruit drinks whereas children had higher fruit intakes. Regional differences in consumption were also detected. Strategies for improving nutrient intake in these vulnerable populations are discussed.

Adolescent↗

PubMed2001

Vitamins in Spanish food patterns: the eVe Study.

OBJECTIVE: To describe vitamin intakes in Spanish food patterns, identify groups at risk for inadequacy and determine conditioning factors that may influence this situation. DESIGN: Pooled-analysis of eight cross-sectional regional nutrition surveys. SUBJECTS: Ten thousand two hundred and eight free-living subjects (4728 men, 5480 women) aged 25-60 years. Respondents of population nutritional surveys carried out in eight Spanish regions (Alicante, Andalucia, Balearic Islands, Canary Islands, Catalunya, Galicia, Madrid and Basque Country) from 1990 to 1998. The samples were pooled together and weighted to build a national random sample. METHODS: Dietary assessment by means of repeated 24-hour recall using photograph models to estimate portion size. Adjusted data for intra-individual variation were used to estimate the prevalence of inadequate intake. A Diet Quality Score (DQS) was computed considering the risk for inadequate intake for folate, vitamin C, vitamin A and vitamin E. DQS scores vary between 0 (good) and 4 (very poor). Influence of lifestyle (smoking, alcohol consumption and physical activity) was considered as well. RESULTS: Inadequate intakes (<2/3 Recommended Dietary Intake) were estimated in more than 10% of the sample for riboflavin (in men), folate (in women), vitamin C, vitamin A, vitamin D and vitamin E. More than 35% of the sample had diets classified as poor quality or very poor quality. Factors identified to have an influence on a poor-quality diet were old age, low education level and low socio-economical level. A sedentary lifestyle, smoking, usual consumption of alcohol and being overweight were conditioning factors for a poor-quality diet as well. CONCLUSION: Results from The eVe Study suggest that a high proportion of the Spanish population has inadequate intakes for at least one nutrient and nearly 50% should adjust their usual food pattern towards a more nutrient-dense, healthier diet.

Adult↗

PubMed2001

Alcohol consumption and academic performance in a population of Spanish high school students.

OBJECTIVE: The present study was designed to identify patterns of alcohol consumption among Spanish high school students and describe the relationship between alcohol intake and school performance. METHOD: The sample population consisted of students, aged 14 to 19 years, who were attending high school during the academic year 1994-95 in the city of Granada in southern Spain. We studied 1,602 (861 female) students (alpha error - 0.05, sampling error = 5%), using a self-administered questionnaire that contained items about individual and family demographics, quantity and frequency of alcohol consumption, and school performance. Total alcohol consumption was recorded as grams (g) of alcohol per week and per day for three categories of alcoholic drinks: wine, beer and distilled spirits. RESULTS: The percentage of nondrinkers was 21.05% for male adolescents and 28.56% for female adolescents. The mean amount of alcohol consumed per week was larger in male than in female students (F= 18.36, l/l,594 df, p < .001) and distilled spirits accounted for the largest proportion of alcohol consumed. No significant differences in drinking patterns were found between students at public and private schools. The risk of academic failure increased considerably when more than 150 g of alcohol were consumed per week (OR: 2.91; 95% CI: 1.94-4.43). CONCLUSIONS: Although we cannot draw any conclusions about the causes of the association between academic failure and teenage drinking, our results do show that the risk of failing increases together with alcohol intake. However, it should be noted that academic achievement is also influenced by many factors other than alcohol consumption.

Achievement↗

PubMed1999

Olive oil supplemented with vitamin E affects mitochondrial coenzyme Q levels in liver of rats after an oxidative stress induced by adriamycin.

In this study we have evaluated the supplementation of olive oil with vitamin E on coenzyme Q concentration and lipid peroxidation in rat liver mitochondrial membranes. Four groups of rats were fed on virgin olive, olive plus 200 mg/kg of vitamin E or sunflower oils as lipid dietary source. To provoke an oxidative stress rats were administered intraperitoneally 10 mg/kg/day of adriamycin the last two days of the experiment. Animals fed on olive oil plus vitamin E had significantly higher coenzyme Q and vitamin E levels but a lower mitochondrial hydroperoxide concentration than rats fed on olive oil. Retinol levels were not affected, by either different diets or adriamycin treatment. In conclusion, an increase in coenzyme Q and alpha-tocopherol in these membranes can be a basis for protection against oxidation and improvement in antioxidant capacity.

Animals↗

PubMed1999

Virgin olive oil and coenzyme Q10 protect heart mitochondria from peroxidative damage during aging.

The mitochondrial theory of aging suggests that this phenomenon is the consequence of random somatic mutations in mitochondrial DNA, induced by long-term exposure to free radical attack. There are two potential dietary means of delaying the effects of free radicals on cellular aging, i.e., enrichment of mitochondrial membranes with monounsaturated fatty acids and supplementation with antioxidants. We have performed a preliminary study on male rats, 6 or 12 month old, fed with diets differing in the nature of the fat (virgin olive oil or sunflower oil) and/or with antioxidant supplementation (coenzyme Q10), analysing hydroperoxide and coenzyme Q9 and Q10 in heart mitochondria. Preliminary results allow us to conclude that the CoQ10 dietetic supplementation as well as the enrichment of the cellular membranes with monounsaturated fatty acids, successfully protect mitochondrial membranes from aged rats against the free radical insult.

Aging↗

PubMed1999

Lifestyle changes in free-living patients with peripheral vascular disease (Fontaine stage II) related to plasma and LDL lipid composition: a 15 month follow-up study.

Peripheral vascular disease (PVD) is characterized by arteriosclerosis and lower extremity ischemia which cause intermittent claudication. Patients grouped in the Fontaine stage II have more than 75% organic stenosis in their large coronary arteries and exhibit a number of alterations in blood coagulation and plasma lipids. The aim of this study was to evaluate an intervention program of lifestyle habits including dietary recommendations, moderate exercise and decreased smoking in a population of patients with PVD for a period of 15 months, with respect to plasma-lipid and lipoprotein composition as well as LDL susceptibility to peroxidation. These parameters are well known risk indicators of arteriosclerosis and coronary heart disease. A total 13 subjects diagnosed with PVD (Fontaine stage II) were selected, while a healthy age-matched group (n=20) was used as a reference. This study design was an uncontrolled trial of lifestyle interventions. The group of patients was examined at 0, 3, 6, 9, 12 and 15 months. Patients smoking one or more packets of cigarettes per day at the beginning of the study (54.2%) decreased smoking by as much as 7.7% 15 months later. In addition, physical activity intensified significantly (walking > 1 km: 13.1-77%) and treadmill running increased over the study period while the energy intake decreased by 10%. The percentage of saturated fat in the diet decreased by 10% while the intake of polyunsaturated fat rose, and monounsaturated-fat intake showed a parallel trend to increase; the average intake of cholesterol also fell by 10% and plasma triglycerides and HDL-cholesterol showed a trend to decrease and increase, respectively. No permanent changes in LDL lipid fractions for patients were detected during the follow-up period and no differences between patients and the age-matched reference group were found. The macrophage uptake of plasma-oxidized LDL was significantly higher in patients than in the reference group and no differences due to the intervention period were detected. In conclusion, the education in lifestyle and nutritional habits of patients with PVD led to reduced energy intake parallel with augmented physical activity as well to a fall in plasma triglycerides and a rise in HDL-cholesterol, which are good indicators of a reduced risk of vascular and myocardial complications.

Analysis of Variance↗

PubMed1999

Effect of extra-virgin olive oil and fish-oil supplementation on plasma lipids and susceptibility of low-density lipoprotein to oxidative alteration in free-living spanish male patients with peripheral vascular disease.

The aim of this study was to analyse the in vivo effect of a diet rich in extra-virgin olive oil and a fish-oil supplement on plasma and lipoprotein fatty-acid composition and on LDL susceptibility to oxidative modification in free-living Spanish male patients with peripheral vascular disease. A total of 12 patients were included in the experimental group which received extra virgin olive oil and a fish oil supplement (group OF). On the other hand, 13 patients which had refined olive oil as the main visible fat were considered as Control group. Plasma triglycerides decreased significantly after three months of dietary intervention. The LDL and plasma fatty-acid pattern in the group OF was characterized by a significant increase in n-3 polyunsaturated fatty acids, mainly 20:5 n-3 and 22:6 n-3. The slopes of LDL oxidative susceptibility were similar between baseline and endpoint values in both groups. However, the uptake of oxidized LDL by macrophages was significantly reduced in OF patients in comparison with the Control group. In conclusion, the daily intake of about 40 g/d of extra-virgin olive oil in combination with a daily supplement of 16 g of fish oil for 3 months in patients with peripheral vascular disease leads to a plasma-lipid profile less atherogenic than in patients having refined olive oil as the main visible food fat. The simultaneous consumption of alpha-tocopherol and natural antioxidants provided by extra-virgin olive oil seems to have a protective effect on the LDL susceptibility to oxidative modifications in spite of a higher proportion of n-3 polyunsaturated fatty acids.

Cholesterol, HDL↗

PubMed1999

Olive oil- and fish oil-enriched diets modify plasma lipids and susceptibility of LDL to oxidative modification in free-living male patients with peripheral vascular disease: the Spanish Nutrition Study.

The present study describes a clinical trial in which Spanish patients suffering from peripheral vascular disease (Fontaine stage II) were given specific lipid supplements. Designed as a longitudinal intervention study, patients were provided with olive oil for 3 months, followed by a 3 month wash-out period, then supplemented with a combination of fish oil and olive oil for the final 3 months. Changes in plasma and lipoprotein fatty acid composition and susceptibility of LDL to in vitro oxidation were examined. Furthermore, lipid-supplement-induced changes in LDL properties were measured as relative electrophoretic mobility and macrophage uptake. In addition, thirteen patients not provided with olive oil and fish oil were included as a control group and twenty healthy age-matched individuals were used as a reference group. A complete clinical study and a nutritional survey concerning food habits and lifestyle were performed every 3 months. Yao indices and claudicometry did not change significantly with dietary intervention although changes in plasma lipid composition suggested an improvement in the condition of the patients. The intake of the fish-oil supplement resulted in significantly increased plasma levels of eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3) in comparison with baseline concentrations, olive-oil and control groups. Fish-oil consumption significantly decreased plasma triacylglycerol levels compared with the olive-oil period, control and reference groups. The susceptibility of LDL to Cu-mediated oxidation was lower in the patients consuming olive oil and the fish-oil supplement than in the control group, and the uptake of LDL by macrophages was significantly lower in the group supplemented with fish oil. In conclusion, consumption of olive oil together with a dietary supplement of fish oil may be useful in the nutritional management of patients suffering from peripheral vascular disease in terms of increasing plasma n-3 long-chain polyunsaturated fatty acids and decreasing susceptibility of LDL to oxidation.

Cholesterol, LDL↗

PubMed1999

Ability of a cocoa product to correct chronic Mg deficiency in rats.

Epidemiological studies have reported that Western diets are often deficient in Mg. We investigated the ability of a cocoa-derived product, used in some European countries as a dietary complement added to milk, to aid recovery from chronic Mg deficiency in rats. The animals were divided into three groups, each of which received a different amount of dietary Mg. Rats in the Mg-deficient (D) group received an Mg-deficient diet (0.225 g Mg/kg food) during 8 weeks. In the cocoa-supplement group (D + CC), the rats consumed the Mg-deficient diet for 5 weeks, and were then switched for 3 further weeks to the same diet supplemented with 3% (wt/wt) cocoa product, so that the Mg content of the diet was 0.27 g/kg food. Rats in the control group (C) were given the same diet as in group D, except that the amount of Mg was 0.56 g Mg/kg food. We measured the concentration of Mg, Ca and P from ten rats in plasma, whole blood, skeletal muscle, heart, kidney and femur in rats that were fed the diets for 35, 42, 49 or 56 days. In animal fed the cocoa-supplemented diet (D + CC) significant improvements were found between days 35 and 56 in the alterations in Mg, Ca and P caused by Mg deficiency in all tissues studied. On day 56, kidney and bone concentrations of Mg and Ca had returned to normal. Our findings show that the habitual use of the cocoa product as a dietary supplement favors correction of the negative effects of long-term feeding with a diet moderately deficient in Mg.

Animals↗

PubMed1999

Oxidative stress induced by exercise and dietary fat modulates the coenzyme Q and vitamin A balance between plasma and mitochondria.

Physical exercise induces oxidative stress. Dietary fat modulates lipid composition of plasma and fatty acid profile of mitochondrial membranes. Over 8 wk, two groups of rats were fed virgin olive oil or sunflower oil as the only fat sources. Both groups were divided into 4 subgroups according to exercise: one of sedentary rats and the other three of rats subjected to different exercises on a treadmill. There was a lower concentration of vitamin A and coenzyme Q in the plasma of animals subjected to exercise compared to the sedentary animals. The concentrations of these molecules in liver and skeletal muscle mitochondria of animals exercised until exhaustion were higher than in sedentary animals. This can suggest the existence of a balance between plasma and mitochondrial membrane for these antioxidants as a response to an oxidative attack.

Animals↗

PubMed1999

The influence of organic amendment and nickel pollution on tomato fruit yield and quality.

The effects of organic fertilization (sludge application) and/or different levels of Ni pollution on tomato fruit yield, quality, nutrition, and Ni accumulation were investigated. The mass loading of sewage sludge solids used in this study for the amendment of a calcareous soil with low organic matter content was 2% (w/w). A control with no sewage sludge amendment was also included (S). Nickel was added to the sludge amended soil at 0, 60, 120 and 240 mg kg-1 concentrations. Sewage sludge addition to the calcareous soil significantly increased fruit yield but did not adversely affect the quality and nutritional status of the tomato fruit. The results demonstrated that sewage sludge could be successfully used as a horticultural fertilizer. Only the highest addition rate of Ni (240 mg kg-1) to an organic amended calcareous soil had negative effects on fruit yield and quality, and caused a Ni accumulation in fruit that could be considered as a hazard for human health. Thus, no toxic problems will be encountered in tomato fruit due to Ni pollution provided the total Ni (soil Ni plus Ni incorporated with sludge amendment) concentration is kept below the maximum concentration of Ni allowed for agricultural alkaline soils in Spain (112 mg Ni kg-1).

Agriculture↗

PubMed1999

Vitamin E supplementation increases the stability and the in vivo antioxidant capacity of refined olive oil.

Two experiments were carried out to investigate if the supplementation with vitamin E affects refined olive oil response to oxidation regarding the stability of the oil and the protection in vivo against lipid peroxidation in rats after its intake in comparison with other edible oils. In experiment 1, samples of virgin olive oil, refined olive oil, refined olive oil supplemented by us with 200 mg/kg vitamin E, and sunflower oil were collected before and after a 60 min frying process. After frying, refined olive oil supplemented with vitamin E compared with the non-supplemented refined olive oil had a higher concentration of alpha-tocopherol (240.34+/-6.07 mg/kg vs. 131.94+/-8.14 mg/kg), more resistance against oxidation (19.01+/-1.88% vs. 10.6+/-2.08%) and less polar components (4.2+/-0.06% vs. 5.45+/-0.22%). In experiment 2, 24 male Wistar rats, divided into 4 groups, were fed on diets based on the same unfried oils (8% w/w) as in experiment 1, for 4 weeks. Two days prior to the end of the experiment, the rats were intraperitoneally administered with adriamycin (10 mg/kg/ day) to provoke an oxidative stress. The rats fed on refined olive oil plus vitamin E compared to the rats fed on non-supplemented refined olive oil had lower hydroperoxides concentrations (26.8+/-2.6 nmol/mg vs. 35.6+/-2.49 nmol/mg) higher coenzyme Q levels (128.1+/-11.97 pmol/mg vs. 81.25+/-9.25 pmol/mg) and higher alpha-tocopherol values (1.23+/-0.04 mmol/mg vs. 0.93+/-0.06 mmol/mg) in microsomes of liver. In conclusion, the supplementation of refined olive oil with 200 mg/kg of vitamin E increases the stability of this oil under pro-oxidant conditions, and its intake decreases the oxidative damage generated by adriamycin in rats.

Animals↗

PubMed1999

Extra-virgin olive oil increases the resistance of LDL to oxidation more than refined olive oil in free-living men with peripheral vascular disease.

Patients with peripheral vascular disease (Fontaine stage II) are characterized by ischemia of the lower extremities, atherosclerosis and alteration of blood coagulation and fibrinolysis. A randomized, two-period, crossover design was used to compare the effects of extra-virgin (VO) and refined olive (RO) oils on plasma lipids and lipoprotein composition and LDL oxidation susceptibility in free-living men with peripheral vascular disease. The oils differed in their antioxidant profile (alpha-tocopherol: 300 vs. 200 mg/kg; phenolic compounds 800 vs. 60) and concentration but not in their fatty acid composition. Subjects were randomly assigned to two groups. The first group (n = 12) received VO with which to freely cook all meals for 3 mo, followed by a 3-mo wash-out period; they then received RO for the final 3 mo. The second group (n = 12) consumed the oils in the opposite order. Energy, fat, polyunsaturated fatty acids (PUFA) and alpha-tocopherol intakes were not different when patients consumed the two oils. Profiles of the major fatty acids in plasma and LDL were not different after consumption of VO and RO. The slope of the line for LDL oxidation vs. the line for copper concentration was significantly higher after the intake of RO than after the intake of VO. Total LDL taken up by macrophages was significantly greater when the men consumed RO rather than VO. We suggest that antioxidants present in VO may protect LDL against oxidation more than does RO in men with peripheral vascular disease.

Aged↗

PubMed1999

Physical exercise affects the lipid profile of mitochondrial membranes in rats fed with virgin olive oil or sunflower oil.

The effects of physical exercise on the lipid profile in mitochondrial membranes of liver and skeletal muscle were examined in rats fed with virgin olive oil or sunflower oil. Thirty male Wistar rats, 21 d old, were randomly assigned to four groups according to fat ingestion and physical activity over an 8-week period. For each type of oil, one group acted as a control group while rats from the other were trained to run for 40 min daily on a horizontal treadmill, at a speed of 35 m/min. The results show that diet affected the fatty acid profile of the mitochondrial membranes from skeletal muscle and liver. Physical exercise also modified the fatty acid profile of the mitochondrial membranes. Total monounsaturated fatty acids decreased (P < 0.001) in liver mitochondria of exercised animals. Total polyunsaturated fatty acids in mitochondrial membranes of liver increased (P < 0.005) after exercise but those in mitochondrial membranes of skeletal muscle decreased (P < 0.05). These changes due to the exercise may arise via several mechanisms, e.g. fluidity regulation; changes in the eicosanoid metabolism; differences in the availability or oxidation rate of the different fatty acids.

Analysis of Variance↗