Reduced lipid peroxidation capacity and desaturation as biochemical markers of aging

Energy, macronutrient and fatty acid intake of French elderly community dwellers and association with socio-demographic characteristics: data from the Bordeaux sample of the Three-City Study

Few data are available regarding dietary habits of the elderly, in particular about fatty acid consumption, whereas these are major risk or protective factors of several age-related diseases. The aim of the present study was to characterise the dietary intake of a French elderly population in terms of energy, macronutrients and fatty acids based on their socio-demographic characteristics. The study population (age range 67·7–94·9 years) consisted of 1786 subjects from Bordeaux (France), included in the Three-City cohort. Dietary assessment was performed by a 24 h recall, allowing the estimation of energy, protein, carbohydrate, total fat, SFA, MUFA and PUFA intakes. Socio-demographic characteristics (age, sex, marital status, educational level and income), practice of sports and BMI were registered. Total energy intake (EI) was lower in women and in older participants ( ≥ 85 years) but higher in single subjects. Higher EI was associated with higher income, but not with educational level. Mean contribution of macronutrients to EI (protein 18 %, carbohydrate 46 % and total fat 31 %) was higher in women than men, except for alcohol. The oldest individuals consumed less protein and more mono- and disaccharides. Excess saturated fat intake (43 % of total fat), associated with a relative deficit in MUFA consumption (36 % of total fat), was observed. The mean 18 : 2n-6 : 18 : 3n-3 ratio was 9.9 and decreased with higher educational level. The present results suggest that being female, older age, being widowed and low income level could be considered as risk factors of inadequate dietary intake.

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.

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-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.

Regional responses in antioxidant system to exercise training and dietary Vitamin E in aging rat brain

We have evaluated the effect of exercise, Vitamin E and a combination of both on the antioxidant enzymes (AOEs)-superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) along with the products of lipid peroxidation (LP)-malondialdehyde (MDA) and lipofuscin-like auto fluorescent substances (LF-like AFS) in discrete brain regions of rats of 4 (young adults), 8 (old adults), 12 (middle-age) and 22 months (mos) old of age. Hippocampus (HC) showed greater increase in GSH-Px activity than cerebral cortex (CC) to exercise and Vitamin E and was irrespective of the age. A combination of both was effective in the CC of all age groups but not in the supplemented sedentary of 12- and 22-mo-olds. CAT activity increased significantly in the HC of supplemented and trained rats but not in the combination group of any age. SOD increased in both the regions of supplemented trainees. However, old were more benefited in terms of maximal elevation in the HC. Vitamin E reduced MDA content in both regions of adult. LF-like AFS decreased significantly in supplemented sedentary and trainees of all ages. Our results demonstrate that an age-related deficit in AOEs in the CC and HC can be overcome through Vitamin E plus exercise, and further suggests the rationale for looking at these markers of oxidative stress in several age-related neuronal diseases.

Age-dependent differences in the stimulation of lipid peroxidation in the heart of rats during immobilization stress

In order to investigate the possible reasons for age-related decrease in myocardium resistance to stress, we carried out a study of lipid peroxidation (LPO) stimulation features in the myocardium of adult (10-12 months) and aged (22-25 months) male Wistar rats during immobilization stress. In our studies of ascorbate-dependent LPO and induced chemiluminescence, we found that immobilization stress is accompanied by decreased efficiency in the induction of free radical processes in the heart of aged rats. An important cause of this phenomenon may be age-dependent changes in the catalytical properties of the cytosolic superoxide dismutase. The pathophysiological consequences of stress-related, age-dependent decreased efficiency of induction of free radical processes in the heart are discussed.

Mating attenuates aging-associated increase of lipid peroxidation activity in C57BL/6J mice

In the frame of the free-radical hypothesis of aging and literature data on increased life span of mated animals, we evaluated brain, kidney, and liver lipid peroxidation in C57Bl/6J mice of various ages and compared lipid peroxidation activity in mated and non-mated mice of both genders. An aging-associated increase (from 3 to 12 months of age) of lipid peroxidation, as measured by malonaldehyde and 4-hydroxyalkenals (MDA + HAE) levels, was observed in the liver and kidney, but not in the brain. Tissue MDA + HAE levels were lower in 12-month old mated mice (housed with animals of opposite gender from three to five months of age) than in 12-month old non-mated animals. There were no gender differences in the observed effect. It is suggested that mating might attenuate the increase of lipid peroxidation associated with aging.

Experimental gerontology in Hungary

Gerontological research has some past and sporadically also some highlights in Hungary, but its present state can be easily deduced from the following data. During the last 12 years and more, well over 10,000 Hungarian scientific papers have been published in well-recognized national or international journals. Altogether approximately 1% of them have been classified as gerontological publications from Hungary. This low figure shows that gerontology has low priority and--unfortunately low support--in Hungary. This statement does not intend to downgrade Hungarian gerontologists, however points out that the Hungarian trends are not far from those of European or world wide interest in aging. Despite the recognition that we have to accept the inevitable fact that industrial societies will have (they already have) an aging population with all the social and medical problems arising, the focus of interest is wide from this significant and interesting (sub)population, which is neglected (sometimes even despised); yet everybody is absolutely eager to join this club. The average of the Hungarian research achievements and publication activities are among the better European achievements. There are some highlights and new trends even initiated by some outstanding Hungarian scientists, yet the overall weight of gerontology research is still an orphan in the Hungarian scientific life. We deal in this short and far from complete summary almost exclusively with experimental gerontology. We have to apologize if we have not included everybody, who also contributed even significantly to this field because the time for the preparation of this overview was short.

Antioxidant and antiaging activity of N-acetylserotonin and melatonin in the in vivo models

It is generally accepted that antioxidant properties of melatonin significantly contribute to its antiaging effect. Antioxidant effects of N-acetylserotonin (NAS), a melatonin precursor and metabolite, might predict its antiaging action as well. The antiaging effect of NAS was studied in female retired breeders and male C3H mice. Both NAS and melatonin administered with drinking water prolonged life span in male animals by about 20% versus control animals (p < 0.01) but did not affect the life span of female mice. Antioxidative activity was evaluated by determining the malonaldehyde + 4-hydroxynonenal (MDA + 4-HNE) and cellular glutathion peroxidase (GPx) levels in male, 11-month-old, C57Bl/6J mice with very limited (if any) capacity to convert pineal NAS into melatonin. NAS increased the antioxidant capacity of kidney. Both NAS and melatonin (four weeks daily i.p. injections) increased the antioxidant capacity of brain as demonstrated by decreased MDA + 4-HNE and increased GPx levels. NAS-treated C57Bl/6J mice experienced a weight loss of 9%, whereas the saline and melatonin groups only 3%. NAS- and melatonin-treated animals had healthy and luxuriant fur coats with some gray fur in the melatonin group; animals in the saline group had large areas of baldness. This study demonstrates, for the first time, the antiaging effect of NAS. This effect needs to be confirmed in animals with impaired capacity to convert NAS into melatonin.