Protein pattern of Xenopus laevis embryos grown in simulated microgravity.

Numerous studies indicate that microgravity affects cell growth and differentiation in many living organisms, and various processes are modified when cells are placed under conditions of weightlessness. However, until now, there is no coherent explanation for these observations, and little information is available concerning the biomolecules involved. Our aim has been to investigate the protein pattern of Xenopus laevis embryos exposed to simulated microgravity during the first 6 days of development. A proteomic approach was applied to compare the protein profiles of Xenopus embryos developed in simulated microgravity and in normal conditions. Attention was focused on embryos that do not present visible malformations in order to investigate if weightlessness has effects at protein level in the absence of macroscopic alterations. The data presented strongly suggest that some of the major components of the cytoskeleton vary in such conditions. Three major findings are described for the first time: (i) the expression of important factors involved in the organization and stabilization of the cytoskeleton, such as Arp (actin-related protein) 3 and stathmin, is heavily affected by microgravity; (ii) the amount of the two major cytoskeletal proteins, actin and tubulin, do not change in such conditions; however, (iii) an increase in the tyrosine nitration of these two proteins can be detected. The data suggest that, in the absence of morphological alterations, simulated microgravity affects the intracellular movement system of cells by altering cytoskeletal proteins heavily involved in the regulation of cytoskeleton remodelling.

Effect of omega-3 fatty acids supplementation on depressive symptoms and on health-related quality of life in the treatment of elderly women with depression: a double-blind, placebo-controlled, randomized clinical trial.

OBJECTIVE: In elderly individuals, depression is one of the most frequently missed diagnoses with negative effects on quality of life. The authors investigated whether a supplement containing long-chain omega-3 polyunsaturated fatty acids (n-3 LCPUFA) improves depressive symptoms and health-related quality of life (HRQoL) in depressed elderly patients. DESIGN: Eight-week, randomized, double-blind, placebo-controlled trial. SETTING: Nursing home in Pavia, Italy. PARTICIPANTS: Forty-six depressed women, aged 66-95 years. INTERVENTION: Twenty-two depressed women were included in the intervention group (n-3 group, which received 2.5 g/d of n-3 LCPUFA, with 1.67 g of eicosapentaenoic acid [EPA] and 0.83 g of docosahesaenoic acid [DHA]), and 24 patients were included in the placebo group. The primary endpoint was the improvement of depressive symptoms, as evaluated by the Geriatric Depression Scale (GDS). Secondary endpoints were the evaluation of HRQoL, by using the Short-Form 36-Item Health Survey (SF-36), and modifications of erythrocyte membrane phospholipids fatty acid profile. All variables were assessed before and after the treatment period of 8 weeks. RESULTS: The mean GDS at 8 weeks was significantly lower compared with the n-3 group. The SF-36 physical and mental components were significantly increased in the intervention group. Compliance was good, as confirmed by erythrocyte membrane phospholipid FA concentrations, with a significant increase of EPA and DHA in the intervention group. CONCLUSION: Supplementation with n-3 LCPUFA is efficacious in the amelioration of depressive symptoms and quality of life in the treatment of depressed elderly female patients.

Antioxidant defences in hydrated and desiccated states of the tardigrade Paramacrobiotus richtersi.

Reactive oxygen species (ROS) are formed in all aerobic organisms, potentially leading to oxidative damage of all biological molecules. A number of defence mechanisms have developed to protect the organism from attack by ROS. Desiccation tolerance is correlated with an increase in the antioxidant potential in several organisms, but the regulation of the antioxidant defence system is complex and its role in desiccation-tolerant organisms is not yet firmly established. To determine if anhydrobiotic tardigrades have an antioxidant defence system, capable of counteracting ROS, we compared the activity of several antioxidant enzymes, the fatty acid composition and Heat shock protein expression in two physiological states (desiccated vs. hydrated) of the tardigrade Paramacrobiotus richtersi. In hydrated tardigrades, superoxide dismutase and catalase show comparable activities, while in desiccated specimens the activity of superoxide dismutase increases. Both glutathione peroxidase and glutathione were induced by desiccation. The percentage of fatty acid composition of polyunsaturated fatty acids and the amount of thiobarbituric acid reactive substances are higher in desiccated animals than in hydrated ones. Lastly, desiccated tardigrades did not differ significantly from the hydrated ones in the relative levels of Hsp70 and Hsp90. These results indicate that the possession of antioxidant metabolism could represent a crucial strategy to avoid damages during desiccation in anhydrobiotic tardigrades.

A rapid method for determining arachidonic:eicosapentaenoic acid ratios in whole blood lipids: correlation with erythrocyte membrane ratios and validation in a large Italian population of various ages and pathologies.

BACKGROUND: Omega-3 and -6 polyunsaturated fatty acids (LCPUFA), are important for good health conditions. They are present in membrane phospholipids.The ratio of total n-6:n-3 LCPUFA and arachidonic acid:eicosapentaenoic acid (AA and EPA), should not exceed 5:1. Increased intake of n-6 and decreased consumption of n-3 has resulted in much higher, ca 10/15:1 ratio in RBC fatty acids with the possible appearance of a pathological "scenario". The determination of RBC phospholipid LCPUFA contents and ratios is the method of choice for assessing fatty acid status but it is labour intensive and time consuming. AIMS OF THE STUDY: [i] To describe and validate a rapid method, suitable for large scale population studies, for total blood fatty acid assay; [ii] to verify a possible correlation between total n-6:n-3 ratio and AA:EPA ratios in RBC phospholipids and in whole-blood total lipids, [iii] to assess usefulness of these ratio as biomarkers of LCPUFA status. METHODS: 1 Healthy volunteers and patients with various pathologies were recruited.2 Fatty acid analyses by GC of methyl esters from directly derivatized whole blood total lipids and from RBC phospholipids were performed on fasting blood samples from 1432 subjects categorised according to their age, sex and any existing pathologies.AA:EPA ratio and the total n-6:n-3 ratio were determined. RESULTS: AA:EPA ratio is a more sensitive and reliable index for determining changes in total blood fatty acid and it is correlated with the ratio derived from extracted RBC phospholipids. CONCLUSIONS: The described AA:EPA ratio is a simple, rapid and reliable method for determining n-3 fatty acid status.

Endogenous antioxidants and radical scavengers.

All living organisms are constantly exposed to oxidant agents deriving from both endogenous and exogenous sources capable to modify biomolecules and induce damages. Free radicals generated by oxidative stress exert an important role in the development of tissue damage and aging. Reactive species (RS) derived from oxygen (ROS) and nitrogen (RNS) pertain to free radicals family and are constituted by various forms of activated oxygen or nitrogen. RS are continuosly produced during normal physiological events but can be removed by antioxidant defence mechanism: the imbalance between RS and antioxidant defence mechanism leads to modifications in cellular membrane or intracellular molecules. In this chapter only endogenous antioxidant molecules will be critically discussed, such as Glutathione, Alpha-lipoic acid, Coenzyme Q, Ferritin, Uric acid, Bilirubin, Metallothioneine, L-carnitine and Melatonin.

Tardigrade Resistance to Space Effects: first results of experiments on the LIFE-TARSE mission on FOTON-M3 (September 2007).

The Tardigrade Resistance to Space Effects (TARSE) project, part of the mission LIFE on FOTON-M3, analyzed the effects of the space environment on desiccated and active tardigrades. Four experiments were conducted in which the eutardigrade Macrobiotus richtersi was used as a model species. Desiccated (in leaf litter or on paper) and hydrated tardigrades (fed or starved) were flown on FOTON-M3 for 12 days in September 2007, which, for the first time, allowed for a comparison of the effects of the space environment on desiccated and on active animals. In this paper, we report the experimental design of the TARSE project and data on tardigrade survival. In addition, data on survival, genomic DNA integrity, Hsp70 and Hsp90 expressions, antioxidant enzyme contents and activities, and life history traits were compared between hydrated starved tardigrades flown in space and those maintained on Earth as a control. Microgravity and radiation had no effect on survival or DNA integrity of active tardigrades. Hsp expressions between the animals in space and the control animals on Earth were similar. Spaceflight induced an increase of glutathione content and its related enzymatic activities. Catalase and superoxide dismutase decreased with spaceflight, and thiobarbituric acid reactive substances did not change. During the flight mission, tardigrades molted, and females laid eggs. Several eggs hatched, and the newborns exhibited normal morphology and behavior.

Simulated microgravity induce glutathione antioxidant pathway in Xenopus laevis embryos.

Space flights cause a number of patho-physiological changes. Oxidative damage has been demonstrated in astronauts after space flights. Oxidative stress is due to an imbalance between production of oxidant and antioxidative defence. In embryos of Xenopus laevis, the glutathione system is an inducible antioxidant defence. For this reason, we investigated the effect of gravity deprivation on endogenous antioxidant enzymes in X. laevis embryos developed for 6 days in a Random Positioning Machine. The results show that glutathione content and the activity of antioxidant enzymes increase in RPM embryos, suggesting the presence of a protective mechanism. An induction of antioxidant defence might play an important role for animals to adapt to micro-gravitational stress, possibly during actual space flights.

Plasma, red blood cells phospholipids and clinical evaluation after long chain omega-3 supplementation in children with attention deficit hyperactivity disorder (ADHD).

Omega-3 and omega-6 long-chain polyunsaturated fatty acids (LCPUFAs), are crucial to brain development and function. Increasing evidence indicates that deficiencies or metabolic imbalances of these fatty acids might be associated with childhood developmental and psychiatric disorders including attention-deficit/hyperactivity disorder (ADHD). Omega-3 are often lacking on modern diets. Moreover preliminary evidences suggest that supplementation with omega-3 LCPUFAs, might help in the management of the ADHD linked behavioural and learning difficulties. However, few studies published to date have involved different populations, study designs, treatments and outcome results. Thus, further researches are required to assess the durability of the treatment effects, to determine optimal composition and dosages of the supplement and to develop reliable ways to identify patients that might have some benefits from this kind of treatment, also because the study of LCPUFAs and their metabolism might offer new approaches to the early identification and management of ADHD. In this paper, we provide new insight on the lipid pattern in plasma and red blood cells (RBC) phospholipids, together with evaluation of the arachidonic acid (AA)/eicosapentaenoic acid (EPA) ratio which seems to correlate with the improvement of the patients both from a biochemical and clinical point of view.