scholarly journals Acute aggressive behavior perturbates the oxidative status of a wild bird independently of testosterone and progesterone

2020 ◽  
Author(s):  
Lucia Mentesana ◽  
Nicolas M. Adreani
Keyword(s):  
Aggressive Behavior ◽  
Redox System ◽  
Oxidative Status ◽  
Antioxidant Compounds ◽  
Enzymatic Antioxidants ◽  
Wild Female ◽  
Physiological Cost ◽  
Antioxidant Concentration ◽  
Conspecific Aggression

AbstractAerobically demanding activities like aggression can lead to an elevated oxidative metabolism affecting the concentration of pro-oxidant and antioxidant compounds and can result in an overall perturbation of the oxidative status. Aggression may also alter the oxidative status indirectly through an increase in testosterone and progesterone concentrations. Given that changes in the oxidative status could represent a physiological cost of aggression, we tested the hypothesis that acute conspecific aggression impairs the oxidative status and evaluated the role of testosterone and progesterone as potential mediators. To achieve this, we experimentally manipulated the aggressive behavior of wild female and male birds and measured the concentrations of pro-oxidants, enzymatic- and non-enzymatic antioxidants, testosterone and progesterone in blood. After 20 minutes of conspecific aggressive behavior, both sexes had lower concentrations of non-enzymatic antioxidants than control individuals. This effect was independent of testosterone and progesterone concentrations, and much stronger in females than in males. Further, only in females (but not in males) being more aggressive came at the expense of lower antioxidant concentration. We provide the first experimental evidence that acute aggressive behavior perturbates the oxidative state of a wild vertebrate independently of testosterone and progesterone, with potential ecological and evolutionary implications given the role of the redox system in shaping life-history traits.

Rutin, a flavonoid with antioxidant activity, improves plant salinity tolerance by regulating K+ retention and Na+ exclusion from leaf mesophyll in quinoa and broad beans

2016 ◽  
Vol 43 (1) ◽  
pp. 75 ◽  
Author(s):  
Hebatollah Ismail ◽  
Jelena Dragišic Maksimovic ◽  
Vuk Maksimovic ◽  
Lana Shabala ◽  
Branka D. Živanovic ◽  
...  
Keyword(s):  
Stress Tolerance ◽  
Antioxidant Compounds ◽  
Salinity Treatment ◽  
Enzymatic Antioxidants ◽  
Adaptive Responses ◽  
Beneficial Effects ◽  
Induced Changes ◽  
Potassium Retention ◽  
And Oxidative Stress

The causal relationship between salinity and oxidative stress tolerance is well established, but specific downstream targets and the role of specific antioxidant compounds in controlling cellular ionic homeostasis remains elusive. In this work, we have compared antioxidant profiles of leaves of two quinoa genotypes contrasting in their salt tolerance, with the aim of understanding the role of enzymatic and non-enzymatic antioxidants in salinity stress tolerance. Only changes in superoxide dismutase activity were correlated with plant adaptive responses to salinity. Proline accumulation played no major role in either osmotic adjustment or in the tissue tolerance mechanism. Among other non-enzymatic antioxidants, rutin levels were increased by over 25 fold in quinoa leaves. Exogenous application of rutin to glycophyte bean leaves improved tissue tolerance and reduced detrimental effects of salinity on leaf photochemistry. Electrophysiological experiments revealed that these beneficial effects were attributed to improved potassium retention and increased rate of Na+ pumping from the cell. The lack of correlation between rutin-induced changes in K+ and H+ fluxes suggest that rutin accumulation in the cytosol scavenges hydroxyl radical formed in response to salinity treatment thus preventing K+ leak via one of ROS-activated K+ efflux pathways, rather than controlling K+ flux via voltage-gated K+-permeable channels.

Study of antioxidant potential in leaves, stems, nuts of Juglans regia L.

2012 ◽  
Vol 1 (10) ◽  
pp. 79 ◽  
Author(s):  
G. Raja* ◽  
Ivvala Anand Shaker ◽  
Inampudi Sailaja ◽  
R. Swaminathan ◽  
S. Saleem Basha ◽  
...  
Keyword(s):  
Free Radicals ◽  
Free Radical ◽  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Juglans Regia ◽  
Radical Scavenging ◽  
Antioxidant Compounds ◽  
Free Radical Damage ◽  
Radical Damage

Natural antioxidants can protect the human body from free radicals and retard the progress of many chronic diseases as well as lipid oxidative rancidity in foods. The role of antioxidants has protected effect against free radical damage that may cause many diseases including cancer. Primary sources of naturally occurring antioxidants are known as whole grains, fruits, and vegetables. Several studies suggest that regular consumption of nuts, mostly walnuts, may have beneficial effects against oxidative stress mediated diseases such as cardiovascular disease and cancer. The role of antioxidants has attracted much interest with respect to their protective effect against free radical damage that may cause many diseases including cancer. Juglans regia L. (walnut) contains antioxidant compounds, which are thought to contribute to their biological properties. Polyphenols, flavonoids and flavonols concentrations and antioxidant activity of Leaves, Stems and Nuts extract of Juglans regia L. as evaluated using DPPH, ABTS, Nitric acid, hydroxyl and superoxide radical scavenging activity, lipid peroxidation and total oxidation activity were determined. The antioxidant activities of Leaves, Stems and Nuts extract of Juglans regia L. were concentration dependent in different experimental models and it was observed that free radicals were scavenged by the test compounds in all the models.

Exploring the effects of physical punishment on aggressive behavior and peer victimization: a conditional process analysis

2016 ◽  
Vol 8 (1) ◽  
pp. 21-32 ◽  
Author(s):  
Patrik Söderberg ◽  
Kaj Bjorkqvist ◽  
Karin Österman
Keyword(s):  
Depressive Symptoms ◽  
Aggressive Behavior ◽  
Peer Victimization ◽  
Online Survey ◽  
Process Analysis ◽  
Physical Punishment ◽  
Process Models ◽  
Content Type ◽  
Conditional Process Analysis

Purpose – Recent studies indicate that exposure to physical punishment is associated with both aggressive behavior and peer victimization at school. The purpose of this paper is to explore the bidirectional relationship between aggressive behavior and peer victimization as outcomes of physical punishment, as well as the role of depressive symptoms. Design/methodology/approach – A sample of 2,424 Finnish upper primary school pupils (1,282 girls, 1,148 boys, mean age=14.2, SD=1.0) completed an online survey during class. Two conditional process models were applied using a macro for SPSS developed by Hayes (2012). Findings – Exposure to physical punishment was found to be associated with both aggressive behavior and peer victimization at school. The effect on victimization was partially mediated by aggressive behavior and depressive symptoms, whereas the effect on aggressive behavior was partially mediated by peer victimization experiences but not by depressive symptoms. The relationship between physical punishment and peer victimization was somewhat stronger for girls than for boys, but this effect was not accounted for by gender differences in depressive symptoms or aggressive behavior. Originality/value – Few studies to date have addressed the connection between aggressive behavior and peer victimization as outcomes of physical punishment. In addition, the study expands on the concept of “victim personality” by examining the mediating role of depressive symptoms. Methodologically, the study is an example of how the statistical software SPSS can be used for multiple mediation and conditional process analysis as an alternative to SEM analyses.

scholarly journals Essential Role of the Redox-Sensitive Kinase p66shc in Determining Energetic and Oxidative Status and Cell Fate in Neuronal Preconditioning

2010 ◽  
Vol 30 (15) ◽  
pp. 5242-5252 ◽  
Author(s):  
J. E. Brown ◽  
S. L. H. Zeiger ◽  
J. C. Hettinger ◽  
J. D. Brooks ◽  
B. Holt ◽  
...  
Keyword(s):  
Cell Fate ◽  
Essential Role ◽  
Oxidative Status

scholarly journals Mechanisms of Response to Salt Stress in Oleander (Nerium oleander L.)

2016 ◽  
Vol 73 (2) ◽  
pp. 249
Author(s):  
Dinesh Kumar ◽  
Mohamad Al Hassan ◽  
Oscar Vicente ◽  
Veena Agrawal ◽  
Monica Boscaiu
Keyword(s):  
Salt Stress ◽  
Abiotic Stress Tolerance ◽  
Soluble Sugar ◽  
Soluble Sugars ◽  
Nerium Oleander ◽  
Antioxidant Systems ◽  
Change Scenario ◽  
Antioxidant Compounds ◽  
Stress Dependent

Elucidating the mechanisms of abiotic stress tolerance in different species will help to develop more resistant plant varieties, contributing to improve agricultural production in a climate change scenario. Basic responses to salt stress, dependent on osmolyte accumulation and activation of antioxidant systems, have been studied in Nerium oleander, a xerophytic species widely used as ornamental. Salt strongly inhibited growth, but the plants survived one-month treatments with quite high NaCl concentrations, up to 800 mM, indicating the the species is relatively resistant to salt stress, in addition to drought. Levels of proline, glycine betaine and soluble sugars increased only slightly in the presence of salt; however, soluble sugar absolute contents were much higher than those of the other osmolytes, suggesting a functional role of these compounds in osmotic adjustment, and the presence of constitutive mechanisms of response to salt stress. High salinity generated oxidative stress in the plants, as shown by the increase of malondialdehyde levels. Antioxidant systems, enzymatic and non-enzymatic, are generally activated in response to salt stress; in oleander, they do not seem to include total phenolics or flavonoids, antioxidant compounds which did not accumulate significantly in salt-trated plants

scholarly journals Enzymatic antioxidants but not baseline glucocorticoids mediate the reproduction–survival trade-off in a wild bird

2018 ◽  
Vol 285 (1892) ◽  
pp. 20182141 ◽  
Author(s):  
Stefania Casagrande ◽  
Michaela Hau
Keyword(s):  
Life History ◽  
Body Condition ◽  
Redox State ◽  
Reproductive Investment ◽  
Redox System ◽  
Reactive Oxygen Metabolites ◽  
Enzymatic Antioxidants ◽  
Trade Off ◽  
Trade Offs ◽  
Nest Provisioning

The trade-off between reproductive investment and survival is central to life-history theory, but the relative importance and the complex interactions among the physiological mechanisms mediating it are still debated. Here we experimentally tested whether baseline glucocorticoid hormones, the redox system or their interaction mediate reproductive investment–survival trade-offs in wild great tits ( Parus major ). We increased the workload of parental males by clipping three feathers on each wing, and 5 days later determined effects on baseline corticosterone concentrations (Cort), redox state (reactive oxygen metabolites, protein carbonyls, glutathione peroxidase [GPx], total non-enzymatic antioxidants), body mass, body condition, reproductive success and survival. Feather-clipping did not affect fledgling numbers, chick body condition, nest provisioning rates or survival compared with controls. However, feather-clipped males lost mass and increased both Cort and GPx concentrations. Within feather-clipped individuals, GPx increases were positively associated with reproductive investment (i.e. male nest provisioning). Furthermore, within all individuals, males that increased GPx suffered reduced survival rates. Baseline Cort increases were related to mass loss but not to redox state, nest provisioning or male survival. Our findings provide experimental evidence that changes in the redox system are associated with the trade-off between reproductive investment and survival, while baseline Cort may support this trade-off indirectly through a link with body condition. These results also emphasize that plastic changes in individuals, rather than static levels of physiological signals, may mediate life-history trade-offs.

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