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Biomedical subjects

M C Polidori

Publications and source records attributed to M C Polidori.

At least 19 recordsLinked to original sources
PubMed2007

Different antioxidant profiles in Italian centenarians: the Sardinian peculiarity.

In this study, 153 Italian centenarians from four different geographical areas, including Modena (northern Italy), Ancona (central Italy), Perugia (central Italy) and Sardinia island (AKEA Project) were enrolled. Plasma levels of vitamin C, uric acid, vitamin A and vitamin E as well as the activities of superoxide dismutase and glutathione peroxidase were measured. Subjects were compared to a younger control population of the same areas, divided into three age groups: <or=60; 61-80 and 81-99 years. The main result of this study is that, whereas in Italian population elevated levels of plasma vitamins A and E seem to be important for longevity, this do not apply to centenarians from Sardinia, in which probably other factors play a more important role.

Aged↗
PubMed2005

Oxidative stress in brain aging, neurodegenerative and vascular diseases: an overview.

According to the free radical theory, aging can be considered as a progressive, inevitable process partially related to the accumulation of oxidative damage into biomolecules -- nucleic acids, lipids, proteins or carbohydrates -- due to an imbalance between prooxidants and antioxidants in favor of the former. More recently also the pathogenesis of several diseases has been linked to a condition of oxidative stress. In this review we focus our attention on the evidence of oxidative stress in aging brain, some of the most important neurodegenerative diseases -- Alzheimer's disease (AD), mild cognitive impairment (MCI), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and Huntington's disease (HD) -- and in two common and highly disabling vascular pathologies--stroke and cardiac failure. Particular attention will be given to the current knowledge about the biomarkers of oxidative stress that can be possibly used to monitor their severity and outcome.

Aging↗
PubMed2005

Predictors of high level of burden and distress in caregivers of demented patients: results of an Italian multicenter study.

BACKGROUND: Considerable suffering is experienced by carers of patients with dementia. Most existing studies do not consider the coexistence of subjective and objective aspects that cause, interacting to each other, this suffering. OBJECTIVES: In this study we: (1) define the high-risk group of caregivers on the bases of the scores obtained on the four scales evaluating burden, distress, depression and anxiety (BDDA) taken into account simultaneously and (2) evaluate risk factors related to the high level of BDDA. SUBJECTS AND METHODS: 419 elderly outpatients with dementia and their caregivers were enrolled. Patients were evaluated for their cognitive, neuropsychological and functional impairment and for comorbidity. Caregivers were evaluated with four scales for the assessment of burden, distress related to neuropsychological disturbances, depression and anxiety. Cluster analysis was used to identify the group with the High level of BDDA (HBDDA). RESULTS: By multiple logistic analysis, disability, specific behavioural disturbances of the patients as well as caregiver's age, type of relationship and living in the south of Italy were observed to be a major risk factor for HBDDA. CONCLUSION: The targeted use of scales specifically assessing BDDA of the caregiver and the identification of particular patient and caregiver characteristics are able to allow a precise and early definition of caregivers at high risk of burden and distress. This might be helpful in planning the correct social/clinical/rehabilitative approach.

Adolescent↗
PubMed2004

Antioxidants for the treatment of mild cognitive impairment.

The isolated deficit in recent memory frequently associated with decline to Alzheimer's disease (AD) is defined as mild cognitive impairment (MCI). The observed progression of MCI to AD suggests a common pathogenesis between these two clinical syndromes, and several neuroimaging, neuropsychological and biological methods are applied with the purpose of identifying subjects at risk of AD. Among these methods, the evaluation of a condition of oxidative stress is gaining increasing attention. Since oxidative stress seems to be involved in the earliest phases of AD, and MCI may be considered as a prodromal phase of dementia, it is an attractive issue to focus therapeutic interventions on the early phase of the disease.

Alzheimer Disease↗
PubMed2003

Plasma antioxidants are similarly depleted in mild cognitive impairment and in Alzheimer's disease.

In order to assess peripheral levels and activities of a broad spectrum of non-enzymatic and enzymatic antioxidants in elderly subjects with mild cognitive impairment (MCI) and Alzheimer's disease (AD), plasma levels of water-soluble (Vitamin C and uric acid) and of lipophilic (Vitamin A, Vitamin E and carotenoids including lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha- and beta-carotene) antioxidant micronutrients as well as activities of plasma and red blood cell (RBC) superoxide dismutase (SOD) and of plasma glutathione peroxidase (GPx) were measured in 25 patients with MCI, 63 AD patients and 53 controls. Peripheral levels and activities of antioxidants were similarly lower in MCI and AD patients as compared to controls. As MCI may represent a prodromal stage of AD, and oxidative damage appears to occur as one of the earliest pathophysiological events in AD, an increased intake of antioxidants in patients with MCI could be helpful in lowering the risk of conversion to dementia.

Aged↗
PubMed2001

Analysis of lipophilic antioxidants in human serum and tissues: tocopherols and carotenoids.

Tocopherols and carotenoids are naturally occurring lipophilic micronutrients, suggested to play a role in the prevention of several degenerative diseases. Thus, methods for the quantification of these nutrients in human samples have been developed during recent years. Blood and tissue levels of tocopherols and carotenoids are influenced by a variety of parameters related to disease, age, diet and lifestyle. This review summarizes general aspects of chromatographic analysis of tocopherols and carotenoids in human samples and deals with information on the outcome of human studies, in which such measurements were applied.

Antioxidants↗
PubMed2001

Profiles of antioxidants in human plasma.

The profile of antioxidants in biological fluids and tissues may be helpful in assessing oxidative stress in humans. Plasma antioxidants can be decreased as compared to established normal values, in abnormal or subnormal conditions, for instance as a consequence of disease-related free radical production. Alternatively, plasma antioxidants may be below the normal range due to insufficient dietary supply. Therefore, the profile of antioxidants can be of use only in conjunction with other parameters of the oxidative stress status. This article examines the profiles of plasma antioxidants in oxidative stress-related conditions, e.g., diabetes and some other diseases, as well as smoking and smoking cessation.

Antioxidants↗
PubMed2001

Heart disease and vascular risk factors in the cognitively impaired elderly: implications for Alzheimer's dementia.

The term "cardiogenic dementia" was introduced a few decades ago to indicate an alteration of consciousness and cognition due to heart disease. Although this term is now disused, the relationship between cardiovascular disease and cognitive impairment is currently of great interest, not only for its potential therapeutic implications. but also for the recently recognized important role that vascular factors appear to play in Alzheimer's disease. The aims of this review are therefore 1) to show data supporting the role of cardiac disease--namely congestive heart failure, myocardial infarction and atrial fibrillation--and other vascular risk factors--i.e., hypertension and diabetes--in the development or worsening of cognitive impairment; 2) to highlight recent observations on the relationship between presence and severity of congestive heart failure/ myocardial infarction/atrial fibrillation and Alzheimer's disease: and 3) to uncover the type of studies needed in this field in order to facilitate a more precise algorithm of dementia prevention as well as intervention in demented patients with cardiovascular disease.

Aged↗
PubMed2001

Peripheral non-enzymatic antioxidant changes with human aging: a selective status report.

Oxidative stress is thought to be involved in the aging process in aerobic organisms and to play a role in the pathogenesis of several disease states. Since free radicals are extremely reactive, shortly half-lived and therefore very difficult to measure directly, oxidative stress has been mainly studied through the search of indirect biomarkers of free radical-induced damage. In aerobic organisms, oxidative damage to tissues and organs is prevented by a network of defenses which includes antioxidant and repairing enzymes as well as small molecules with scavenging ability, such as antioxidant vitamins. For these reasons, the assay of antioxidant vitamins and of small molecular free radical scavengers in biological milieus may be used, if appropriately performed, to quantify the defense status against oxidative damage and to provide an indirect estimate of free radical production in aging humans. Since several conflicting data have been reported in this area, this review is aimed to summarize the existing evidence and possible faults of the research focusing on the role of plasma concentrations of small-molecular, non-enzymatic antioxidants in the process of senescence in healthy humans.

Aging↗
PubMed2001

Age and sex influence on oxidative damage and functional status in human skeletal muscle.

A reduction in muscle mass, with consequent decrease in strength and resistance, is commonly observed with advancing age. In this study we measured markers of oxidative damage to DNA, lipids and proteins, some antioxidant enzyme activities as well Ca2+ transport in sarcoplasmic reticulum membranes in muscle biopsies from vastus lateralis of young and elderly healthy subjects of both sexes in order to evaluate the presence of age- and sex-related differences. We found a significant increase in oxidation of DNA and lipids in the elderly group, more evident in males, and a reduction in catalase and glutathione transferase activities. The experiments on Ca2+ transport showed an abnormal functional response of aged muscle after exposure to caffeine, which increases the opening of Ca2+ channels, as well a reduced activity of the Ca2+ pump in elderly males. From these results we conclude that oxidative stress play an important role in muscle aging and that oxidative damage is much more evident in elderly males, suggesting a gender difference maybe related to hormonal factors.

Adolescent↗
PubMed2001

Plasma vitamin C levels are decreased and correlated with brain damage in patients with intracranial hemorrhage or head trauma.

BACKGROUND AND PURPOSE: Free radical hyperproduction may play an important role in brain hemorrhage and ischemia/reperfusion injury. The aims of this study were to assess whether antioxidant depletion occurs after intracranial hemorrhage (ICH) and head trauma (HT) and to evaluate the relation between the diameter of the brain lesion, the degree of the neurological impairment, and any observed antioxidant changes. METHODS: We measured plasma levels of vitamin C (ascorbic acid, AA), uric acid (UA), vitamin E (alpha-tocopherol), and ubiquinol-10 in 13 patients with ICH and 15 patients with HT on the day of the brain injury and subsequently every other day up to 1 week. Patients were compared with 40 healthy control subjects. RESULTS: ICH and HT patients had significantly lower plasma levels of AA compared with healthy subjects, in contrast to plasma levels of UA, alpha-tocopherol, and ubiquinol-10. AA levels were significantly inversely correlated with the severity of the neurological impairment as assessed by the Glasgow Coma Scale and the National Institutes of Health Stroke Scale. AA levels were also significantly inversely correlated with the major diameter of the lesion. In addition, mean plasma AA levels were lower in jugular compared with peripheral blood samples obtained from 5 patients. CONCLUSIONS: These findings suggest that a condition of oxidative stress occurs in patients with head trauma and hemorrhagic stroke of recent onset. The consequences of early vitamin C depletion on brain injury as well as the effects of vitamin C supplementation in ICH and HT patients remain to be addressed in further studies.

Adult↗
PubMed2000

Plasma antioxidants and longevity: a study on healthy centenarians.

A large body of experimental research indicates that oxidative stress contributes to the processes related to aging and to the pathogenesis of several age-related diseases. Vitamins and antioxidant enzymes have a fundamental role in defending the organism from oxidative stress. To better understand the role of antioxidants in human aging, we measured plasma levels of vitamin C (ascorbic acid), uric acid, vitamin E (alpha-tocopherol), vitamin A (retinol), carotenoids, total thiol groups, and the activity of plasma superoxide dismutase (SOD) and glutathione peroxidase (GPX) as well as the activity of red blood cell (RBC) SOD in 32 healthy centenarians-17 elderly subjects aged 80-99 years, 34 elderly subjects aged 60-79 years, and 24 adults aged less than 60 years. Considering the "noncentenarians" only, we observed a consistent behavior in the antioxidant pattern, with a decrease of the nonenzymatic antioxidants and an increase of the enzymatic antioxidant activities relative to age. Remarkably, centenarians were characterized as having the highest levels of vitamins A and E, whereas the activities of both plasma and RBC SOD, which increase with age, decreased in centenarians. From these results, it is evident that healthy centenarians show a particular profile in which high levels of vitamin A and vitamin E seem to be important in guaranteeing their extreme longevity.

Aged↗
PubMed2000

Physical activity and oxidative stress during aging.

Physical activity and exercise have several beneficial effects for physical and psychological health in young and aged subjects. Exercise may reduce age-related lean body mass loss and risk for several chronic diseases including coronary artery disease, hypertension, non-insulin-dependent diabetes mellitus, anxiety, depression, functional decline, and frailty. Exercise, however, especially when performed strenuously, is associated with increased production of reactive oxygen species, able to consume endogenous antioxidants and eventually to damage biological molecules and key cellular components. Therefore, the balance between beneficial and potentially harmful effects of exercise might be of particular importance in the elderly, in which nutritional deficiencies, sedentary lifestyle, and comorbidity commonly concur to a depletion of the antioxidant reservoir of the organism and increased susceptibility to oxidative stress. The aim of this review is to summarize current experimental, clinical, and epidemiological knowledge regarding known associations and potential links between oxidative stress and physical activity/exercise during aging. Before a final recommendation can be made with respect to the possible preventive and therapeutical role of antioxidant supplementation in aged exercising people, there is a substantial need for further studies to be performed on this topic.

Aged↗
PubMed2000

Antioxidant profile and early outcome in stroke patients.

BACKGROUND AND PURPOSE: Experimental studies provide evidence of an association between ischemic stroke and increased oxidative stress, but data in humans are still limited and controversial. The purpose of this study was to investigate the time course of plasma antioxidant changes in ischemic stroke patients. METHODS: Plasma antioxidants, including water-soluble (vitamin C and uric acid) and lipid-soluble (vitamins A and E) compounds as well as antioxidant enzyme activities in plasma (superoxide dismutase [SOD] and glutathione peroxidase) and erythrocytes (SOD), were measured by high-performance liquid chromatography (antioxidant vitamins) and by spectrophotometry (antioxidant enzymes) in 38 subjects (25 men and 13 women aged 77.2+/-7.9 years) with acute ischemic stroke of recent onset (<24 hours) on admission, after 6 and 24 hours, and on days 3, 5, and 7. Antioxidant levels in patients on admission were compared with those of age- and sex-matched controls. RESULTS: Mean antioxidant levels and activities in patients on admission were lower than those of controls and showed a gradual increase over time. Patients with the worst early outcome (death or functional decline) had higher vitamin A and uric acid plasma levels and lower vitamin C levels and erythrocyte SOD activity than those who remained functionally stable. CONCLUSIONS: These results suggest that the majority of antioxidants are reduced immediately after an acute ischemic stroke, possibly as a consequence of increased oxidative stress. A specific antioxidant profile is associated with a poor early outcome.

Aged↗
PubMed1999

Oxidative damage to mitochondrial DNA in Huntington's disease parietal cortex.

Oxidative damage to DNA may play a role in both normal aging and in neurodegenerative diseases. Using a sensitive high-performance liquid chromatography (HPLC) assay, we examined concentrations of 8-hydroxy-2-deoxyguanosine (OH8dG) in mitochondrial DNA (mtDNA) isolated from frontal and parietal cerebral cortex and from cerebellum in 22 Huntington's disease (HD) patients and 15 age-matched normal controls. A significant increase in OH8dG in mtDNA of parietal cortex was found in HD patients as compared with controls, while there were no significant changes in frontal cortex or cerebellum. The present findings are consistent with regionally specific oxidative damage in HD, which may be a further evidence of a metabolic defect.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed1999

Age-dependent increases in oxidative damage to DNA, lipids, and proteins in human skeletal muscle.

A role for oxidative damage in normal aging is supported by studies in experimental animals, but there is limited evidence in man. We examined markers of oxidative damage to DNA, lipids, and proteins in 66 muscle biopsy specimens from humans aged 25 to 93 years. There were age-dependent increases in 8-hydroxy-2-deoxyguanosine (OH8dG), a marker of oxidative damage to DNA, in malondialdehyde (MDA), a marker of lipid peroxidation, and to a lesser extent in protein carbonyl groups, a marker of protein oxidation. The increases in OH8dG were significantly correlated with increases in MDA. These results provide evidence for a role of oxidative damage in human aging which may contribute to age-dependent losses of muscle strength and stamina.

Adult↗