In vitro, ex vivo and clinical approaches to evaluate the potential effect of Gentiana lutea extract on skin.

BACKGROUND: Dark circles affect subjects of all ages and in all skin types. They can be treated by various methods, particular by topical solutions. This investigation was directed towards exploring the effect of gentiopicroside (GP) on the skin around the eyes. For this, an extract of Gentiana lutea (GIE) containing GP (65% by dry matter) was evaluated on oxidant and angiogenesis parameters using in vitro and ex-vivo studies. A clinical experimentation was also realized. METHODS: The effect of GIE at different concentrations on antioxidant gene was evaluated in vitro by RT-qPCR after treatment of NHDF. The effect of 2.93 µg mL-1 GIE on the release of VEGF-A and VEGF-C by NHDF was also studied. The effect of 87.9 µg mL-1 GIE was also evaluated on pseudotube formation in a coculture system of normal dermal microvascular endothelial cells (HMVEC-d)-NHDF stimulated or not with VEGF as pro-angiogenic factor. Prior to these assays, preliminary cytotoxicity assays were performed using a standard WST-8 reduction assay. The expressions of carboxymethyl-lysine and glyoxalase-1 were quantified on skin explants topically treated with 147 µg mL-1 GIE in basal and UVA-irradiated conditions. A clinical study was conducted in 22 subjects using topical twice daily for 14 days on eye area (split-face application: cream containing 147 µg mL-1 GIE versus placebo). 3D image acquisition and skin colour measurement were performed at D0 and D14. RESULTS: Treatment of GIE upregulated the gene expression of NFE2L2 and downregulated the expression of CXCL8. GIE targeted AGEs pathways and reduced the formation of pseudotubes. A total of 147 µg mL-1 GIE gel cream significantly reduced significantly the average roughness and relief of the upper eyelid skin as well as the redness of dark circles after 14 days of application. CONCLUSION: By acting on the pathway of AGEs, VEGF-A and VEFG-C, GIE seems to allow a rejuvenation of the skin resulting, among others, in a decrease in redness. It now would be interesting to evaluate the efficacy of GIE on skin around eyes microbiota, antibacterial gentiopicroside property being well-established.

CONTEXTE: Le contour des yeux est une zone sensible. Les cernes affectent les sujets de tout âge et de tout type de peau. Différentes solutions peuvent être proposées, dont les solutions topiques. Cette étude visait a explorer l'effet d'un extrait de Gentiana lutea (GIE) riche en gentiopicroside (65% de matière sèche) sur des paramètres d'oxydation et d'angiogenèse au moyen d'études in vitro et ex-vivo. Une expérimentation clinique a également été réalisée. MÉTHODES: L'effet du GIE a différentes concentrations sur des gènes antioxydants a été évalué in vitro par RT-qPCR après traitement de fibroblastes (NHDF). L'effet de 2.93 µg mL−1 GIE sur la libération de VEGF-A et VEGF-C a également été étudié. Il en est de même pour l'effet de 87.9 µg g mL−1 GIE sur la formation de pseudotubes qui a été évalué dans un système de co-culture de cellules endothéliales (HMVEC-d)- NHDF stimulées ou non avec du VEGF comme facteur pro-angiogénique. Les expressions de la carboxymethyl-lysine et de la glyoxalase-1 ont été quantifiées sur des explants cutanés traites par voie topique avec 147 µg g mL−1 GIE dans des conditions basales et irradiées par UVA. Une étude clinique a été menée sur vingt-deux sujets en utilisant un traitement topique deux fois par jour pendant 14 jours sur le contour des yeux (crème contenant 147 µg g mL−1 GIE contre placebo). L'acquisition d'images 3D et la mesure de la couleur de la peau ont été réalisées a J0 et J14. RÉSULTATS: Le traitement par GIE a augmenté l'expression génétique de NFE2L2 et diminue l'expression de CXCL8. GIE a cible les voies des AGEs et a réduit la formation de pseudotubes. 147 µg g mL−1 GIE gel crème a significativement réduit la rugosité moyenne et le relief de la peau de la paupière supérieure ainsi que la rougeur des cernes après 14 jours d'application. CONCLUSION: En agissant sur la voie des AGEs, du VEGF-A et du VEFG-C, GIE semble permettre un rajeunissement de la peau se traduisant, entre autres, par une diminution des rougeurs. Il serait maintenant intéressant d'évaluer l'efficacité du GIE sur le microbiote de la peau du contour des yeux, la propriété antibactérienne du gentiopicroside étant bien établie.

Aspalathus linearis (Rooibos) Targets Adipocytes and Obesity-Associated Inflammation.

Excess weight and obesity are the fifth leading cause of death globally, and sustained efforts from health professionals and researchers are required to mitigate this pandemic-scale problem. Polyphenols and flavonoids found in Aspalathus linearis-a plant widely consumed as Rooibos tea-are increasingly being investigated for their positive effects on various health issues including inflammation. The aim of our study was to examine the effect of Rooibos extract on obesity and the associated low-grade chronic inflammatory state by testing antioxidant activity, cytokine secretions, macrophage polarization and the differentiation of human adipocytes through the development of adipospheroids. Rooibos extract significantly decreased ROS production and the secretion of pro-inflammatory cytokines (IFN-γ, IL-12, IL-2 and IL-17a) in human leukocytes. Additionally, Rooibos extract down-regulated LPS-induced macrophage M1 polarization, shown by a significant decrease in the expression of pro-inflammatory cytokines: TNFα, IL-8, IL-6, IL-1ß and CXCL10. In addition, Rooibos inhibited intracellular lipid accumulation and reduced adipogenesis by decreasing the expression of PPARγ, Ap2 and HSL in adipospheroids. A significant decrease in leptin expression was noted and this, more interestingly, was accompanied by a significant increase in adiponectin expression. Using a co-culture system between macrophages and adipocytes, Rooibos extract significantly decreased the expression of all studied pro-inflammatory cytokines and particularly leptin, and increased adiponectin expression. Thus, adding Rooibos tea to the daily diet is likely to prevent the development of obesity associated with chronic low-level inflammation.

Microalgae n-3 PUFAs Production and Use in Food and Feed Industries.

N-3 polyunsaturated fatty acids (n-3 PUFAs), and especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are essential compounds for human health. They have been proven to act positively on a panel of diseases and have interesting anti-oxidative, anti-inflammatory or anti-cancer properties. For these reasons, they are receiving more and more attention in recent years, especially future food or feed development. EPA and DHA come mainly from marine sources like fish or seaweed. Unfortunately, due to global warming, these compounds are becoming scarce for humans because of overfishing and stock reduction. Although increasing in recent years, aquaculture appears insufficient to meet the increasing requirements of these healthy molecules for humans. One alternative resides in the cultivation of microalgae, the initial producers of EPA and DHA. They are also rich in biochemicals with interesting properties. After defining macro and microalgae, this review synthesizes the current knowledge on n-3 PUFAs regarding health benefits and the challenges surrounding their supply within the environmental context. Microalgae n-3 PUFA production is examined and its synthesis pathways are discussed. Finally, the use of EPA and DHA in food and feed is investigated. This work aims to define better the issues surrounding n-3 PUFA production and supply and the potential of microalgae as a sustainable source of compounds to enhance the food and feed of the future.

Characterisation of microbiota in saliva, bronchoalveolar lavage fluid, non-malignant, peritumoural and tumour tissue in non-small cell lung cancer patients: a cross-sectional clinical trial.

BACKGROUND: While well-characterised on its molecular base, non-small cell lung cancer (NSCLC) and its interaction with local microbiota remains scarcely explored. Moreover, current studies vary in source of lung microbiota, from bronchoalveolar lavage fluid (BAL) to tissue, introducing potentially differing results. Therefore, the objective of this study was to provide detailed characterisation of the oral and multi-source lung microbiota of direct interest in lung cancer research. Since lung tumours in lower lobes (LL) have been associated with decreased survival, characteristics of the microbiota in upper (UL) and lower tumour lobes have also been examined. METHODS: Using 16S rRNA gene sequencing technology, we analysed microbiota in saliva, BAL (obtained directly on excised lobe), non-malignant, peritumoural and tumour tissue from 18 NSCLC patients eligible for surgical treatment. Detailed taxonomy, diversity and core members were provided for each microbiota, with analysis of differential abundance on all taxonomical levels (zero-inflated binomial general linear model with Benjamini-Hochberg correction), between samples and lobe locations. RESULTS: Diversity and differential abundance analysis showed clear separation of oral and lung microbiota, but more importantly, of BAL and lung tissue microbiota. Phylum Proteobacteria dominated tissue samples, while Firmicutes was more abundant in BAL and saliva (with class Clostridia and Bacilli, respectively). However, all samples showed increased abundance of phylum Firmicutes in LL, with decrease in Proteobacteria. Also, clades Actinobacteria and Flavobacteriia showed inverse abundance between BAL and extratumoural tissues depending on the lobe location. While tumour microbiota seemed the least affected by location, peritumoural tissue showed the highest susceptibility with markedly increased similarity to BAL microbiota in UL. Differences between the three lung tissues were however very limited. CONCLUSIONS: Our results confirm that BAL harbours unique lung microbiota and emphasise the importance of the sample choice for lung microbiota analysis. Further, limited differences between the tissues indicate that different local tumour-related factors, such as tumour type, stage or associated immunity, might be the ones responsible for microbiota-shaping effect. Finally, the "shift" towards Firmicutes in LL might be a sign of increased pathogenicity, as suggested in similar malignancies, and connected to worse prognosis of the LL tumours. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT03068663. Registered February 27, 2017.

Microbiota: a novel regulator of pain.

Among the various regulators of the nervous system, the gut microbiota has been recently described to have the potential to modulate neuronal cells activation. While bacteria-derived products can induce aversive responses and influence pain perception, recent work suggests that "abnormal" microbiota is associated with neurological diseases such as Alzheimer's, Parkinson's disease or autism spectrum disorder (ASD). Here we review how the gut microbiota modulates afferent sensory neurons function and pain, highlighting the role of the microbiota/gut/brain axis in the control of behaviors and neurological diseases. We outline the changes in gut microbiota, known as dysbiosis, and their influence on painful gastrointestinal disorders. Furthermore, both direct host/microbiota interaction that implicates activation of "pain-sensing" neurons by metabolites, or indirect communication via immune activation is discussed. Finally, treatment options targeting the gut microbiota, including pre- or probiotics, will be proposed. Further studies on microbiota/nervous system interaction should lead to the identification of novel microbial ligands and host receptor-targeted drugs, which could ultimately improve chronic pain management and well-being.

Characterisation of gut, lung, and upper airways microbiota in patients with non-small cell lung carcinoma: Study protocol for case-control observational trial.

BACKGROUND: Several studies have confirmed the important role of the gut microbiota in the regulation of immune functions and its correlation with different diseases, including cancer. While brain-gut and liver-gut axes have already been demonstrated, the existence of a lung-gut axis has been suggested more recently, with the idea that changes in the gut microbiota could affect the lung microbiota, and vice versa. Likewise, the close connection between gut microbiota and cancer of proximal sites (intestines, kidneys, liver, etc.) is already well established. However, little is known whether there is a similar relation when looking at world's number one cause of death from cancer-lung cancer. OBJECTIVE: Firstly, this study aims to characterise the gut, lung, and upper airways (UAs) microbiota in patients with non-small cell lung cancer (NSCLC) treated with surgery or neoadjuvant chemotherapy plus surgery. Secondly, it aims to evaluate a chemotherapy effect on site-specific microbiota and its influence on immune profile. To our knowledge, this is the 1st study that will analyse multi-site microbiota in NSCLC patients along with site-specific immune response. METHODS: The study is a case-controlled observational trial. Forty NSCLC patients will be divided into 2 groups depending on their anamnesis: Pchir, patients eligible for surgery, or Pct-chir, patients eligible for neoadjuvant chemotherapy plus surgery. Composition of the UAs (saliva), gut (faeces), and lung microbiota (from broncho-alveolar lavage fluid (BALF) and 3 lung pieces: "healthy" tissue distal to tumour, peritumoural tissue and tumour itself) will be analysed in both groups. Immune properties will be evaluated on the local (evaluation of the tumour immune cell infiltrate, tumour classification and properties, immune cell phenotyping in BALF; human neutrophil protein (HNP) 1-3, ß-defensin 2, and calprotectin in faeces) and systemic level (blood cytokine and immune cell profile). Short-chain fatty acids (SCFAs) (major products of bacterial fermentation with an effect on immune system) will be dosed in faecal samples. Other factors such as nutrition and smoking status will be recorded for each patient. We hypothesise that smoking status and tumour type/grade will be major factors influencing both microbiota and immune/inflammatory profile of all sampling sites. Furthermore, due to non-selectivity, the same effect is expected from chemotherapy.

Exercise and taurine in inflammation, cognition, and peripheral markers of blood-brain barrier integrity in older women.

Immunosenescence contribute to increase the blood-brain barrier (BBB) permeability, leading cognitive impairment and neurodegeneration. Thus, we investigated the anti-inflammatory effect of exercise and taurine supplementation on peripheral markers of BBB, inflammation, and cognition of elderly women. Forty-eight elderly women (age, 83.58 ± 6.9 years) participated in the study, and were allocated into combined exercise training (CET: n = 13), taurine supplementation (TAU: n = 12), exercise training associated with taurine (CET+TAU: n = 11), or control (CG: n = 12) groups. Exercise was applied twice a week (multi-modal exercise). Taurine ingestion was 1.5 g., once a day. Participants were evaluated before and after 14-weeks of intervention. Plasma levels of interleukin (IL)-1ß, IL-1ra, IL-6, IL-10, IL-17, tumor necrosis factor alpha (TNF-α), and serum concentration of S100ß and neuron specific enolase (NSE) were determined. The mini mental state examination (MMSE) was also applied. Concentrations of S100ß were maintained in all intervention groups, while a subtle increase in the CG was found. NSE levels increased only in TAU group (p < 0.05). CET reduced TNF-α, IL-6, and IL-1ß/IL-1ra, IL-6/IL10, and TNF-α/IL-10 ratios (p < 0.05). TAU decreased the IL-1ß/IL-1ra ratio (p < 0.05). MMSE score increased only in the CET+TAU group (p < 0.05). Multiple regression analysis showed that there was a trend for changes in IL-1ß and the Charlson Comorbidity Index to be independently associated with changes in S100ß. Exercise and taurine decreased inflammation, and maintained the BBB integrity in elderly women. Exercise emerged as an important tool to improve brain health even when started at advanced ages.

Desired Turbulence? Gut-Lung Axis, Immunity, and Lung Cancer.

The microbiota includes different microorganisms consisting of bacteria, fungi, viruses, and protozoa distributed over many human body surfaces including the skin, vagina, gut, and airways, with the highest density found in the intestine. The gut microbiota strongly influences our metabolic, endocrine, and immune systems, as well as both the peripheral and central nervous systems. Recently, a dialogue between the gut and lung microbiota has been discovered, suggesting that changes in one compartment could impact the other compartment, whether in relation to microbial composition or function. Further, this bidirectional axis is evidenced in an, either beneficial or malignant, altered immune response in one compartment following changes in the other compartment. Stimulation of the immune system arises from the microbial cells themselves, but also from their metabolites. It can be either direct or mediated by stimulated immune cells in one site impacting the other site. Additionally, this interaction may lead to immunological boost, assisting the innate immune system in its antitumour response. Thus, this review offers an insight into the composition of these sites, the gut and the lung, their role in shaping the immune system, and, finally, their role in the response to lung cancer.

Marine algae as attractive source to skin care.

As the largest organ in the human body, the skin has multiple functions of which one of the most important is the protection against various harmful stressors. The keratinised stratified epidermis and an underlying thick layer of collagen-rich dermal connective tissues are important components of the skin. The environmental stressors such as ultraviolet radiation (UVR) and pollution increase the levels of reactive oxygen species (ROS), contributing to clinical manifestations such as wrinkle formation and skin aging. Skin aging is related to the reduction of collagen production and decrease of several enzymatic activities including matrix metalloproteinases (MMPs), which degrade collagen structure in the dermis; and tissue inhibitor of metalloproteinases (TIMPs), which inhibit the action of MMPs. In addition to alterations of DNA, signal transduction pathways, immunology, UVR, and pollution activate cell surface receptors of keratinocytes and fibroblasts in the skin. This action leads to a breakdown of collagen in the extracellular matrix and a shutdown of new collagen synthesis. Therefore, an efficient antioxidants strategy is of major importance in dermis and epidermis layers. Marine resources have been recognised for their biologically active substances. Among these, marine algae are rich-sources of metabolites, which can be used to fight against oxidative stress and hence skin aging. These metabolites include, among others, mycosporine-like amino acids (MAAs), polysaccharides, sulphated polysaccharides, glucosyl glycerols, pigments, and polyphenols. This paper reviews the role of oxidative processes in skin damage and the action of the compounds from algae on the physiological processes to maintain skin health.

Strength Training Decreases Inflammation and Increases Cognition and Physical Fitness in Older Women with Cognitive Impairment.

Introduction: Cognitive impairment that affects older adults is commonly associated with an inflammatory imbalance, resulting in decreased physical fitness. Exercise has been pointed to mitigate immunosenescence and cognitive impairment associated with aging, while increase in physical fitness. However, few studies explored the relationship between changes in cytokine concentration and improvement on cognition due to elastic band strength training. The aim of this study was to investigate the effects of strength training on pro-and anti-inflammatory cytokines, hematological markers and physical fitness of older women with cognitive impairment. Methods: Thirty-three women (82.7 ± 5.7 years old) participated in the study and were divided in two groups: strength exercise training group (ST; n = 16) and Control Group (CG; n = 17) and were evaluated before and after 28 weeks of the exercise program. The CG did not undergo any type of exercise programs. Data for IL-10, TNF-α, IFN-γ, C-Reactive Protein (CRP), white blood counts (WBC), red blood counts (RBC), Mini Mental State Examination (MMSE) and physical fitness tests were analyzed in both moments. Results: IL-10 increased in the ST group without changes in CG. TNF-α and CRP increased in the control group while no changes were observed for IFN-γ in both groups. Strength training decreased leukocyte and lymphocyte counts and increase hemoglobin, mean cell volume and mean cell hemoglobin concentration. The MMSE score increased in strength training group but remained unchanged in the control group. A correlation between the variation of granulocyte counts and the MMSE scores was also observed within the total sample. An improvement in physical fitness was observed with strength training. Conclusion: Resistance exercise promoted better anti-inflammatory balance and physical performance simultaneously with an increase in cognitive profile in older women with cognitive impairment.

Study of the Effects of Betaine and/or C-Phycocyanin on the Growth of Lung Cancer A549 Cells In Vitro and In Vivo.

We investigated the effects of betaine, C-phycocyanin (C-PC), and their combined use on the growth of A549 lung cancer both in vitro and in vivo. When cells were coincubated with betaine and C-PC, an up to 60% decrease in viability was observed which is significant compared to betaine (50%) or C-PC treatment alone (no decrease). Combined treatment reduced the stimulation of NF-κB expression by TNF-α and increased the amount of the proapoptotic p38 MAPK. Interestingly, combined treatment induced a cell cycle arrest in G2/M phase for ~60% of cells. In vivo studies were performed in pathogen-free male nude rats injected with A549 cells in their right flank. Their daily food was supplemented with either betaine, C-PC, both, or neither. Compared to the control group, tumour weights and volumes were significantly reduced in either betaine- or C-PC-treated groups and no additional decrease was obtained with the combined treatment. This data indicates that C-PC and betaine alone may efficiently inhibit tumour growth in rats. The synergistic activity of betaine and C-PC on A549 cells growth observed in vitro remains to be further confirmed in vivo. The reason behind the nature of their interaction is yet to be sought.

Left atrial resection for T4 lung cancer without cardiopulmonary bypass: technical aspects and outcomes.

BACKGROUND: Extended resection for lung cancer may improve survival of selected patients. Left-atrial resection is infrequently performed and surgical techniques are rarely reported; thus, oncologic results and survival rates remain uncertain. Our study describes surgical techniques, postoperative outcomes, and oncologic results of patients who received a combined multimodality treatment. METHODS: Between October 2004 and March 2012 in our institution, 19 patients underwent extended lung resection involving the left atrium without cardiopulmonary bypass. We reviewed perioperative treatments, surgical procedures, and postoperative morbidity, mortality, and long-term survival rates. RESULTS: Sixteen patients (68.4%) underwent neoadjuvant treatment including chemotherapy or radiotherapy. Eighteen pneumonectomies (94.7%) were performed, of which 12 (63.1%) were right sided. Dissection of the interatrial septum was complete in 4 patients (33.3%). Complete resection was achieved in 17 patients (89.4%) and 2 other patients (10.5%) were considered R1. The T-status was pT4 in all patients. Overall postoperative morbidity was 52.6%. The 30-day mortality rate was 10.5% and the 90-day mortality rate was 15.7%. Fifteen patients (93.7%) underwent adjuvant treatment. The mean follow-up time was 32.5 months. The 5-year probability of survival was 43.7%. Three patients (15.7%) were alive at greater than 6 years postsurgery. CONCLUSIONS: Extended lung surgery with partial resection of the left atrium is a feasible procedure with acceptable morbidity. An interatrial septum dissection, by increasing the length of the atrial cuff, allows complete resection. Long-term survival can be achieved in highly selected patients who have undergone multimodal therapy.

Lung cancer: what are the links with oxidative stress, physical activity and nutrition.

Oxidative stress appears to play an essential role as a secondary messenger in the normal regulation of a variety of physiological processes, such as apoptosis, survival, and proliferative signaling pathways. Oxidative stress also plays important roles in the pathogenesis of many diseases, including aging, degenerative disease, and cancer. Among cancers, lung cancer is the leading cause of cancer in the Western world. Lung cancer is the commonest fatal cancer whose risk is dependent on the number of cigarettes smoked per day as well as the number of years smoking, some components of cigarette smoke inducing oxidative stress by transmitting or generating oxidative stress. It can be subdivided into two broad categories, small cell lung cancer and non-small-cell lung cancer, the latter is the most common type. Distinct measures of primary and secondary prevention have been investigated to reduce the risk of morbidity and mortality caused by lung cancer. Among them, it seems that physical activity and nutrition have some beneficial effects. However, physical activity can have different influences on carcinogenesis, depending on energy supply, strength and frequency of exercise loads as well as the degree of exercise-mediated oxidative stress. Micronutrient supplementation seems to have a positive impact in lung surgery, particularly as an antioxidant, even if the role of micronutrients in lung cancer remains controversial. The purpose of this review is to examine lung cancer in relation to oxidative stress, physical activity, and nutrition.

Relationship between eating-behavior disorders and psychological parameters in male first-year physical education students.

This study explores the prevalence of disordered eating attitudes in a sample of male first-year university students engaged in a physical education program and examines the relationships between emotional intelligence, coping, and emotional eating in relation to disordered-eating (DE) attitudes. A total of 140 students completed the following questionnaires: the eating attitudes test, the bar-on emotional intelligence questionnaire, the coping inventory stress scale, and the Dutch eating behavior questionnaire. The number of participants represented 80% of the male students registered in this discipline at the authors' university. Twenty percent of students presented DE attitudes even though they were of normal weight. The bar-on EQ-I results indicated that students with DE attitudes had lower levels of emotional intelligence (EI) scores than students without DE attitudes (control group). Moreover, they scored higher than the control group on coping styles such as avoidance-oriented coping, emotion-oriented coping, and emotional eating. The DE group presented a positive correlation between DE attitudes symptoms and both avoidance- and emotion-oriented coping but a negative correlation between DE attitudes and task-oriented coping. There was also a significant negative correlation between DE attitudes and EI score. Another result from this group indicated an association between EI score and emotional-eating score (p < .05, r = -.44) and also a positive correlation between emotion-oriented coping and emotional eating (p < .01, r = .47). The findings highlight future research potential on the role of emotions and EI in DE symptoms, which may be beneficial in the context of collaborative care management intervention.

Lecturing to 200 students and its effects on cytokine concentration and salivary markers of adrenal activation.

Stress not only activates the SAM system and the hypothalamic-pituitary-adrenal axes, but also the immune system. The aims of this study are to assess the physiological variations in saliva (cytokines, cortisol and alpha-amylase) and perceived stress in professors when they had to lecture to 200 students. A total of eight unstimulated saliva samples were collected from nine professors: four on a working day that included the lecture and four controls on a working day without a lecture. The professors also rated subjective stress on a seven-point scale 5 min before the lecture, immediately after the lecture and at the same times on the control day. The lecture elicited substantial increases in subjective stress ratings, with the values on the lecture day significantly higher than those on the control day. Lecturing resulted in significant increases in Tumor Necrosis Factor (TNF)-α, Interleukin (IL)-2 and IL-4 concentrations, but did not affect the IL-10 values. These changes appeared to be concomitant with changes in the concentrations of the stress markers, alpha-amylase and cortisol. The mechanisms by which psychosocial stress can induce cytokine changes and modify the activity of salivary alpha-amylase are not entirely understood, and further research is thus warranted.

Lipid peroxidation and antioxidant status in rat: effect of food restriction and wheel running.

Using the activity-based anorexia model, the aim of this investigation was to explore antioxidant enzyme activity (catalase, superoxide dismutase), total antioxidant status (TAS), and alpha-tocopherol in blood, liver, and gastrocnemius muscle associated with the food restriction and voluntary wheel running during 8 days. In addition, lipid peroxidation was measured by measurements of malondialdehyde (MDA). Wistars rats (n = 56) were randomly assigned to one of four groups: an ad lib sedentary group, a control wheel activity group, a food restriction-induced hyperactivity group (1 h/day ad lib food, 23 h/day ad lib wheel access), and a food-restricted sedentary group. The animals were killed when the rats in the food-restricted group had lost 25% of their free feeding weight. Antioxidant enzyme activities and TAS in blood, liver, and gastrocnemius muscle were unaffected by voluntary wheel running. A wheel activity effect (P < 0.05) was obtained for the MDA concentrations in plasma, with lower concentrations in trained animals. Food restriction effects were obtained for antioxidant capacity in liver, as well as for CAT activity in the gastrocnemius muscle and plasma MDA concentrations with lower values in the restricted animals. On the other hand, the food-restricted rats showed higher plasma TAS concentrations (P < 0.05) and higher alpha-tocopherol concentrations in the liver (P < 0.05) when compared to animals fed ad libitum. Our results also showed that food restriction coupled to wheel running decreased antioxidant parameters in liver, and plasmatic MDA concentrations and increased TAS plasma concentrations when compared to the ad libitum sedentary situation.

Oxidative stress : relationship with exercise and training.

Free radicals are reactive compounds that are naturally produced in the human body. They can exert positive effects (e.g. on the immune system) or negative effects (e.g. lipids, proteins or DNA oxidation). To limit these harmful effects, an organism requires complex protection - the antioxidant system. This system consists of antioxidant enzymes (catalase, glutathione peroxidase, superoxide dismutase) and non-enzymatic antioxidants (e.g. vitamin E [tocopherol], vitamin A [retinol], vitamin C [ascorbic acid], glutathione and uric acid). An imbalance between free radical production and antioxidant defence leads to an oxidative stress state, which may be involved in aging processes and even in some pathology (e.g. cancer and Parkinson's disease). Physical exercise also increases oxidative stress and causes disruptions of the homeostasis. Training can have positive or negative effects on oxidative stress depending on training load, training specificity and the basal level of training. Moreover, oxidative stress seems to be involved in muscular fatigue and may lead to overtraining.