Fish Oil Supplementation Improves the Repeated-Bout Effect and Redox Balance in 20-30-Year-Old Men Submitted to Strength Training

Herein, we investigated the effect of fish oil supplementation combined with a strength-training protocol, for 6 weeks, on muscle damage induced by a single bout of strength exercise in untrained young men. Sixteen men were divided into two groups, supplemented or not with fish oil, and they were evaluated at the pre-training period and post-training period. We investigated changes before and 0, 24, and 48 h after a single hypertrophic exercise session. Creatine kinase (CK) and lactate dehydrogenase (LDH) activities, plasma interleukin-6 (IL-6) and C-reactive protein (CRP) levels, and the redox imbalance were increased in response to the single-bout session of hypertrophic exercises at baseline (pre-training period) and decreased during the post-training period in the control group due to the repeated-bout effect (RBE). The fish oil supplementation exacerbated this reduction and improved the redox state. In summary, our findings demonstrate that, in untrained young men submitted to a strength-training protocol, fish oil supplementation is ideal for alleviating the muscle injury, inflammation, and redox imbalance induced by a single session of intense strength exercises, highlighting this supplementation as a beneficial strategy for young men that intend to engage in strength-training programs.

Irisin: An anti-inflammatory exerkine in aging and redox-mediated comorbidities

Human beings lead largely sedentary lives. From an evolutionary perspective, such lifestyle is not beneficial to health. Exercise can promote many enabling pathways, particularly through circulating exerkines, to optimize individual health and quality of life. Such benefits might explain the protective effects of exercise against aging and noncommunicable diseases. Nevertheless, the miRNA-mediated molecular mechanisms and exerkine interorgan crosstalk that underlie the beneficial effects of exercise remain poorly understood. In this mini review, we focused on the exerkine, irisin, mainly produced by muscle contraction during adaptation to exercise and its beneficial effects on body homeostasis. Herein, the complex role of irisin in metabolism and inflammation is described, including its subsequent effects on thermogenesis through browning to control obesity and improve glycemic regulation for diabetes mellitus control, its potential to improve cognitive function (via brain derived neurotrophic factor), and its pathways of action and role in aging.

The advantages of physical exercise as a preventive strategy against NAFLD in postmenopausal women

BACKGROUND

The prevalence and severity of nonalcoholic fatty liver disease (NAFLD) increase in women after menopause. This narrative review discusses the causes and consequences of NAFLD in postmenopausal women and describes how physical activity can contribute to its prevention.

METHODS

The authors followed the narrative review method to perform a critical and objective analysis of the current knowledge on the topic. The Medical Subject Heading keywords 'physical exercise', 'menopause', 'hormone replacement therapy', 'estradiol' and 'NAFLD' were used to establish a conceptual framework. The databases used to collect relevant references included Medline and specialized high-impact journals.

RESULTS

Higher visceral adiposity, higher rate of lipolysis in adipose tissue after oestrogen drop and changes in the expression of housekeeping proteins involved in hepatic lipid management are observed in women after menopause, contributing to NAFLD. Excessive liver steatosis leads to hepatic insulin resistance, oxidative stress and inflammation, accelerating NAFLD progression. Physical activity brings beneficial effects against several postmenopausal-associated complications, including NAFLD progression. Aerobic and resistance exercises partially counteract alterations induced by metabolic syndrome in sedentary postmenopausal women, impacting NAFLD progression and severity.

CONCLUSIONS

With the increased global obesity epidemic in developing countries, NAFLD is becoming a severe problem with increased prevalence in women after menopause. Evidence shows that physical activity may delay NAFLD development and severity in postmenopausal women, although the prescription of age-appropriate physical activity programmes is advisable to assure the health benefits.

Combined Chair-Based Exercises Improve Functional Fitness, Mental Well-Being, Salivary Steroid Balance, and Anti-microbial Activity in Pre-frail Older Women

Introduction

Regular exercise has long been shown to positively impact the immune system responsiveness and improve mental well-being (MWB). However, the putative links between biomarkers of mental health and immune efficiency in exercising subjects have been scarcely investigated. The aim of this study was to verify the effect of a 14-week combined chair-based exercise program (CEP) on salivary steroid hormones and anti-microbial proteins, functional fitness, and MWB indexes in pre-frail older women.

Methods

The participant women (82.8 4.6 years old; n = 32) were randomly divided into the exercising group (CEP, n = 17) and the non-exercising control group (CG, n = 15). The pre/post assessment included: (1) salivary anti-microbial proteins lysozyme; (Lys) and immunoglobulin-A (IgA); (2) salivary steroid hormones of testosterone (TT) and cortisol (COR); (3) functional fitness (gait speed, hand grip strength, and static balance); (4) MWB questionnaires (happiness, depression state, satisfaction with life, and stress).

Results

Significant differences with large Cohen's (d) effect sizes were found on increased salivary TT (p < 0.05; d = 0.60) after exercise intervention. The results revealed a decrease in IgA levels after CEP (p < 0.01, d = 0.30). The increase in subjective happiness levels (p < 0.05, d = 0.30) and decrease of stress perception (p < 0.01, d = 2.60) and depressive state (p < 0.05, d = 0.30) were found after intervention in the CEP group. Robust statistical differences in gait speed (p < 0.05; d = 0.60) and balance tests (p < 0.05; d = 0.80) were also found in the CEP group. In control, COR increased moderately (p < 0.05; d = 0.65) while no changes were found for the other indicators. Correlation analyses showed inter-dependence between pre-post variations of MWB, biochemical indexes, and fitness function (e.g., COR inverse correlation with hand grip strength and balance tests).

Conclusion

The CEP program was able to improve functional-fitness performance, decrease feelings of stress, and increase happiness. The CEP also induced clinically relevant hormonal and immune responses, which suggests that chair exercises that combine muscular strength, balance, and gait speed training are promising interventions to improve physical and mental health of older pre-frail adults.

Benthic macroinvertebrate community in the Sinos river drainage basin, Rio Grande do Sul, Brazil

Aquatic macroinvertebrate fauna is a relevant component of limnic continental aquatic ecosystems, playing an important role in several processes with relevant biocomplexity. The present study characterized the benthic macroinvertebrate fauna found in three hydric bodies in the Sinos river drainage basin regarding community structure. Sample was collected from January to December 2013 in three locations in the basin: the city of Caraá (29 °45'45.5"S/50°19'37.3"W), the city of Rolante (29°38'34.4"S/50°32'33.2"W) and the city of Igrejinha (29°36'10.84"S/50°48'49.3"W). Abiotic components (pH, dissolved oxygen and temperature) were registered and collected samples were identified up to family type. Average annual pH, dissolved oxygen and temperature were similar in all locations. A total of 26,170 samples were collected. Class Insecta (Arthropods) represented 85.5% of total sample. Platyhelmintes, Mollusca and Annelida samples were also registered. A total of 57 families were identified for the drainage basin and estimators (Chao-1, Chao-2 and jackknife 2) estimated richness varying from 60 to 72 families.

Adenoviruses of canine and human origins in stool samples from free-living pampas foxes (Lycalopex gymnocercus) and crab-eating foxes (Cerdocyon thous) in São Francisco de Paula, Rio dos Sinos basin

The spread of enteric viruses of domestic animals and human beings to wild species can be facilitated by the resistance of these viruses on the environment and their ability to be transmitted by water and contaminated food. The health status of the populations of pampas foxes Lycalopex gymnocercus) and crab-eating foxes (Cerdocyon thous) is largely unknown and the landscapes occupied by these animals in southern Brazil have been threatened by human occupation and expansion of agriculture. In this work, the search of genomes of human and canine adenoviruses in feces from these wild carnivores was used to track the dissemination of domestic animals and human pathogens to the free-living populations in a wildlife reserve located in southern Brazil. This was performed by virus-specific differential real-time polymerase chain reactions (qPCR) on stool specimens, avoiding capture and additional stress to the animals. Genus-specific conventional reverse-transcriptase PCR (RT-PCR) was complementarily performed aiming the detection of enteroviruses (EV) and rotaviruses (RV) on these same samples. HAdV genomes were found on 14 out of the 17 (82.35%) stool samples analysed, whereas CAV was found co-infecting 5 of these samples. RV genomes were detected on 7 of the 17 samples (41.18%) and all samples were negative for EV. The results point to the dispersion of HAdV and RV at a high rate to these species of South American wild carnivores, which can be an effect of growing anthropisation of the habitat of these animals.

Molybdate:sulfate ratio affects redox metabolism and viability of the dinoflagellate Lingulodinium polyedrum

Molybdenum is a transition metal used primarily (90% or more) as an additive to steel and corrosion-resistant alloys in metallurgical industries and its release into the environment is a growing problem. As a catalytic center of some redox enzymes, molybdenum is an essential element for inorganic nitrogen assimilation/fixation, phytohormone synthesis, and free radical metabolism in photosynthesizing species. In oceanic and estuarine waters, microalgae absorb molybdenum as the water-soluble molybdate anion (MoO4(2-)), although MoO4(2-) uptake is thought to compete with uptake of the much more abundant sulfate anion (SO4(2-), approximately 25 mM in seawater). Thus, those aspects of microalgal biology impacted by molybdenum would be better explained by considering both MoO4(2-) and SO4(2-) concentrations in the aquatic milieu. This work examines toxicological, physiological and redox imbalances in the dinoflagellate Lingulodinium polyedrum that have been induced by changes in the molybdate:sulfate ratios. We prepared cultures of Lingulodinium polyedrum grown in artificial seawater containing eight different MoO4(2-) concentrations (from 0 to 200 μM) and three different SO4(2-) concentrations (3.5 mM, 9.6 mM and 25 mM). We measured sulfur content in cells, the activities of the three major antioxidant enzymes (superoxide dismutase, catalase, and ascorbate peroxidase), indexes of oxidative modifications in proteins (carbonyl content) and lipids (thiobarbituric acid-reactive substances, TBARS), the activities of the molybdenum-dependent enzymes xanthine oxidase and nitrate reductase, expression of key protein components of dinoflagellate photosynthesis (peridinin-chlorophyll a protein and ribulose-1,5-biphosphate carboxylase/oxidase) and growth curves. We find evidence for Mo toxicity at relatively high [MoO4(2-)]:[SO4(2-)] ratios. We also find evidence for extensive redox adaptations at Mo levels well below lethal levels.

The interplay between thiol-compounds against chromium (VI) in the freshwater green alga Monoraphidium convolutum: toxicology, photosynthesis, and oxidative stress at a glance

In this paper, the multifaceted Cr(VI) toxicity over the freshwater green alga Monoraphidium convolutum was assessed by concomitantly monitoring thiol-dependent redox balances, photosynthesis activity and growth-survival scores. Control group showed exponential growth rate at (5.78±0.29) division/day until 8th day with linear increasing chlorophyll a/protein ratios (CHLa/PROT) throughout the period. Cultures of M. convolutum were exposed for 5 days to Cr(VI) concentrations from 0 up to 100mg/L showing that CHLa/PROT ratios were sensibly affected, in agreement to the calculated LC(50,48 h) (5.38±0.72) mg/L from the concentration-response curve of cell mortality after 48 h. Regarding photosynthesis effects, Cr(VI) concentrations >1.0 mg/L showed significant increases in short-term (after 2 h) electron transfer rates (ETR) and quantum yields of photosystem II (Φ(PSII)), followed by subsequent decline of both parameters after 48 and 72 h. Biochemical analyses showed that maximal GSH concentrations in algal cultures were observed upon 1mg Cr(VI)/L and higher dichromate concentrations dramatically increased the activity of antioxidant GSH-dependent enzymes ascorbate peroxidase and glutathione reductase. However, no variation was observed in the cellular GSH levels, whereas GSSG and lipid peroxidation indexes abruptly increased upon 10 mg Cr(VI)/L exposure. Altogether, plant physiology, photosynthesis and biochemical data suggest that the GSH-dependent antioxidant system is capable to sustain M. convolutum viability through efficient photosynthesis activity and adequate antioxidant responses up to Cr(VI) concentrations of 1.0mg/L, when redox unbalances were first evidenced.

Combined astaxanthin and fish oil supplementation improves glutathione-based redox balance in rat plasma and neutrophils

The present study aimed to investigate the effects of daily (45 days) intake of fish oil (FO; 10mg EPA/kg body weight (BW) and 7 mg DHA/kg BW) and/or natural ASTA (1mg ASTA/kg BW) on oxidative stress and functional indexes of neutrophils isolated from Wistar rats by monitoring superoxide (O(2)(-)), hydrogen peroxide (H(2)O(2)), and nitric oxide (NO()) production compared to the progression of auto-induced lipid peroxidation and Ca(2+) release in activated neutrophils. Furthermore, phagocytic capacity, antioxidant enzyme activities, glutathione-recycling system, and biomarkers of lipid and protein oxidation in neutrophils were compared to the redox status. Our results show evidence of the beneficial effects of FO+ASTA supplementation for immune competence based on the redox balance in plasma (significant increase in GSH-dependent reducing power), non-activated neutrophils (increased activity of the glutathione-recycling enzymes GPx and GR) and PMA-activated neutrophils (lower O(2)(-), H(2)O(2), and NO() generation, reduced membrane oxidation, but higher phagocytic activity). Combined application of ASTA and FO promoted hypolipidemic/hypocholesterolemic effects in plasma and resulted in increased phagocytic activity of activated neutrophils when compared with ASTA or FO applied alone. In PMA-activated neutrophils, ASTA was superior to FO in exerting antioxidant effects. The bulk of data reinforces the hypothesis that habitual consumption of marine fish (e.g. salmon, which is a natural source of both astaxanthin and fish oil) is beneficial to human health, in particular by improving immune response and lowering the risk of vascular and infectious diseases.

Combined fish oil and astaxanthin supplementation modulates rat lymphocyte function

PURPOSE

Higher intakes of n-3 polyunsaturated fatty acids that are abundant in marine fishes have been long described as a "good nutritional intervention" with increasing clinical benefits to cardiovascular health, inflammation, mental, and neurodegenerative diseases. The present study was designed to investigate the effect of daily fish oil (FO-10 mg EPA/kg body weight (BW) and 7 mg DHA/kg BW) intake by oral gavage associated with the antioxidant astaxanthin (ASTA-1 mg/kg BW) on the redox metabolism and the functional properties of lymphocytes from rat lymph nodes.

METHODS

This study was conducted by measurements of lymphocyte proliferation capacity, ROS production [superoxide (O₂(•-)) and hydrogen peroxide (H₂O₂)], nitric oxide (NO(•)) generation, intracellular calcium release, oxidative damage to lipids and proteins, activities of major antioxidant enzymes, GSH/GSSG content, and cytokines release.

RESULTS

After 45 days of FO + ASTA supplementation, the proliferation capacity of activated T- and B-lymphocytes was significantly diminished followed by lower levels of O₂(•-), H₂O₂ and NO(•) production, and increased activities of total/SOD, GR and GPx, and calcium release in cytosol. ASTA was able to prevent oxidative modification in cell structures through the suppression of the oxidative stress condition imposed by FO. L: -selectin was increased by FO, and IL-1β was decreased only by ASTA supplementation.

CONCLUSION

We can propose that association of ASTA with FO could be a good strategy to prevent oxidative stress induced by polyunsaturated fatty acids and also to potentiate immuno-modulatory effects of FO.

Bird community in a forest patch isolated by the urban matrix at the Sinos River basin, Rio Grande do Sul State, Brazil, with comments on the possible local defaunation

We compared the avifauna recorded in a recent survey in an urban park (Parque Municipal Henrique Luís Roessler, Parcão) and surroundings, Novo Hamburgo, RS, with past data, to evaluate the possible alterations in species composition over time. Of the 265 species compiled as original elements of that region, 114 were found at Parcão. Among forest species, 37% were considered locally extinct. The most affected guild was the large frugivores, with nine extinct species and one survivor (Trogon surrucura). Birds highly sensitive to disturbance as well as endemic species were the most extinguished. The possible causes for this loss are fragmentation, hunting and environmental changes. The diversity today is threatened, thus conservation measures are necessary in that region. The most important actions are: maintenance of ecological corridors, protection of natural remnant areas and the establishment of protected areas.

Phenanthrene decreases neutrophil function by disrupting intracellular redox balance

The aim of the present work was to evaluate whether the treatment of human neutrophils with phenanthrene (PHN) can alter the phagocytic and microbicidal capacity of these cells by causing a disruption in redox balance. Peripheral neutrophils from healthy subjects were treated for up to 24 h with increasing concentrations of phenanthrene. Phagocytic/microbicidal activities, antioxidant enzymes, oxidative lesions (thiobarbituric acid-reactive substances and protein thiol and carbonyl groups) and redox signaling compounds (intracellular Ca(2+), superoxide, hydrogen peroxide and nitric oxide) were monitored on neutrophils exposed to 10 microg PHN ml(-1). Cell viability decreased abruptly at PHN concentrations above 10 microg ml(-1) (LC50 = 20.86 +/- 0.51 microg ml(-1) and p-sigmoidal slope = 19.88 +/- 10.11). Phagocytic and microbicidal capacities were decreased by 60 and 82%, respectively. Substantial increases in total-/Mn-SOD, catalase, glutathione peroxidase and glutathione reductase activities (by 61, 15, 87, 245 and 70%, respectively) matched the oxidative injury obtained in TBARS (2.5-fold higher) and protein thiol (54% lower). Diminished productions of superoxide by 18% and hydrogen peroxide by 29% were observed in association to exacerbated calcium (27%) and nitric oxide (63%) levels. The data indicate that phenanthrene might be associated with substantial reduction in human neutrophil functions due to severe intracellular redox imbalances.

A polyethylenetherephthalate (PET) device for sampling freshwater benthic macroinvertebrates

A new device to sample freshwater benthic macroinvertebrates was used in a low and sandy stretch of a Brazilian sub-tropical river (the River Cai, Triunfo, RS) and in one of its small tributaries, Bom Jardim brook (Arroio Bom Jardim). In this study, the effectiveness of this device, a PET sampler, was tested at different sites in the river and the brook throughout the four seasons between 2001-2002. Comparisons were made by PCA and ANOVA, both employing a bootstrap procedure based on similarity matrices. The PET sampler proved to be a reliable tool for detection of seasonal and spatial differences in richness, total abundance of organisms, and Shannon's diversity index in both river and brook and is therefore recommended for use in the monitoring of macroinvertebrate communities in this system.

Astaxanthin and peridinin inhibit oxidative damage in Fe(2+)-loaded liposomes: scavenging oxyradicals or changing membrane permeability?

Astaxanthin and peridinin, two typical carotenoids of marine microalgae, and lycopene were incorporated in phosphatidylcholine multilamellar liposomes and tested as inhibitors of lipid oxidation. Contrarily to peridinin results, astaxanthin strongly reduced lipid damage when the lipoperoxidation promoters-H(2)O(2), tert-butyl hydroperoxide (t-ButOOH) or ascorbate-and Fe(2+):EDTA were added simultaneously to the liposomes. In order to check if the antioxidant activity of carotenoids was also related to their effect on membrane permeability, the peroxidation processes were initiated by adding the promoters to Fe(2+)-loaded liposomes (encapsulated in the inner aqueous solution). Despite that the rigidifying effect of carotenoids in membranes was not directly measured here, peridinin probably has decreased membrane permeability to initiators (t-ButOOH > ascorbate > H(2)O(2)) since its incorporation limited oxidative damage on iron-liposomes. On the other hand, the antioxidant activity of astaxanthin in iron-containing vesicles might be derived from its known rigidifying effect and the inherent scavenging ability.

Daily variations of antioxidant enzyme and luciferase activities in the luminescent click-beetle Pyrearinus termitilluminans: cooperation against oxygen toxicity

Several lines of investigation have suggested an interplay between bioluminescence (BL) and oxyradical metabolism, mainly in bacteria and beetles. Although not yet confirmed, luminescent beetles seem to be challenged daily by oxidative conditions imposed by higher oxygen absorption necessary to enhance light emission for courtship (adult lampyrids and elaterids) and prey attraction (e.g. Pyrearinus termitilluminans larvae). This work reports the activities of luciferase, superoxide dismutase (SOD), catalase and dehydroascorbate reductase (DHAR) and total glutathione content at different times of the day in the bright prothorax and dim abdomen of larval Pyrearinus termitilluminans (Coleoptera: Elateridae), investigating a possible adjuvant role for luciferase in oxygen detoxification. Luciferase activity in the prothorax was shown to peak at 7 p.m., which is the time when P. termitilluminans larvae light up for prey attraction. In their habitat, P. termitilluminans larvae emit light until 8.30 p.m. However, at 8 p.m., prothorax luciferase activity achieved basal levels and total glutathione content declined to the daily lowest value, possibly resulting from hyperoxidative conditions during this time. Significant increases in the activities of total SOD (28%) and catalase (37%) were observed in the prothorax at 9 p.m., which should minimize the extent of damage from this potentially hazardous period. Prothorax total SOD (42% higher than daily average) and abdomen CuZnSOD (41%) and catalase (95%) activities showed extra peaks at 7-10 a.m., and abdomen DHAR activity was maximal (37%) earlier (4-7 a.m.). These morning increases in antioxidant enzyme activities may be associated with biological events other than bioluminescence, e.g. intense physical activity for digging tunnels and/or digestion of captured preys. These data suggest that oxyradical pathway and bioluminescence are coordinated, especially in the prothorax, to minimize the oxidative stress imposed by higher irrigation of the photocytes with O(2) when P. termitilluminans larvae emit light.

Luciferase and urate may act as antioxidant defenses in larval Pyrearinus termitilluminans (Elateridae: Coleoptera) during natural development and upon 20-hydroxyecdysone treatment

Insects show unique adaptations to cope with oxidative challenges during larval development, metamorphosis and adulthood. Our previous findings suggested that bioluminescence may act as an auxiliary oxygen-detoxifying mechanism in larvae of Pyrearinus termitilluminans (Elateridae: Coleoptera). We now study the antioxidant status in larval P. termitilluminans, evaluated in terms of levels of chemical and enzymatic antioxidant defenses, as compared to luciferase activity in the prothorax (intensely bright) and abdomen (dim) of the larvae, during natural- and 20-hydroxyecdysone (20-HE)-induced development. In the prothorax, relative total SOD activities in small (< 1 cm), medium (1-2 cm) and large (> 2 cm) larvae were 1.00:0.53:0.32. Catalase activity also decreased with development (1.00:0.69:0.55). In contrast, prothorax luciferase activities and urate content increased with ratios of 1.0:2.2:2.5 and 1:15:97, respectively. No increases were found in the level of prothorax lipid and protein oxidation. In the abdomen, luciferase activity decreased markedly with development (1.00:0.33:0.17), as did other antioxidant enzymes, including dehydroascorbate reductase (1.00:0.59:0.17) and levels of lipid peroxidation products and protein carbonyls. Similar variations were observed in antioxidant enzyme activities when the larvae were treated with 20-HE, except for prothorax catalase. As observed in natural larval growth, luciferase activity was augmented (two-fold in prothorax) upon steroid treatment, and the levels of thiobarbituric acid-reactive substances were magnified in both segments. The increase of luciferase activity and a higher urate content in the prothorax during larval development may reflect metabolic adaptations to keep levels of oxyradicals low in order to compensate for decreased antioxidant enzyme activities.

Bioluminescence as a possible auxiliary oxygen detoxifying mechanism in elaterid larvae

This work examines the hypothesis that beetle bioluminescent reactions may primarily have evolved to provide an auxiliary O2 detoxifying mechanism. The activities of antioxidant enzymes and of luciferase in the prothorax (bright) and abdomen (dim) of luminous larval Pyrearinus termitilluminans (Coleoptera: Elateridae) were measured after previous challenge with either hyperoxia, hypoxia, or the firefly luciferase inhibitor luciferin 6'-methyl ether (LME). Upon exposure to pure O2 for 72 h, the prothorax activities of total superoxide dismutase (SOD) and catalase were found to increase by 85% and 50%, respectively. Concomitantly, levels of luciferase and luciferin increased 80% and 50%. Assays of thiobarbituric acid reactive substances (TBARS) showed significantly augmented lipid peroxidation only in the abdomen (30%) where levels of antioxidant enzymes and especially luciferase are low. In contrast, exposure to hypoxia (2% O2) led to significant increases in prothorax citrate synthase (85%), succinate dehydrogenase (25%), and lactate dehydrogenase (30%) activities, but not in luciferase or antioxidant enzyme levels. LME administration alone decreased luciferase activities 20% but did not alter prothorax SOD activity. Prothorax SOD activity was increased by concomitant LME and hyperoxia treatments (30%), along with higher levels of TBARS (25%) and protein reactive carbonyl groups (50%). Altogether these data suggest that in elaterids, bioluminescence and reactions catalyzed by antioxidant enzymes may cooperate to minimize oxidative stress.