Search results for "Active oxygen"

Crosstalk between mitochondria and peroxisomes

2015

Mitochondria and peroxisomes are small ubiquitous organelles. They both play major roles in cell metabolism, especially in terms of fatty acid metabolism, reactive oxygen species (ROS) production, and ROS scavenging, and it is now clear that they metabolically interact with each other. These two organelles share some properties, such as great plasticity and high potency to adapt their form and number according to cell requirements. Their functions are connected, and any alteration in the function of mitochondria may induce changes in peroxisomal physiology. The objective of this paper was to highlight the interconnection and the crosstalk existing between mitochondria and peroxisomes. Speci…

Electrochemical monitoring of ROS influence on seedlings and germination response to salinity stress of three species of the tribe Inuleae.

2019

Solid-state electrochemical methods have been applied to the establishment of patterns of plant growth and response to saline stress using seedlings of Inula helenium L., Dittrichia viscosa (L.) Greuter (Inula viscosa (L.) Aiton), Limbarda crithmoides (L.) Dumort (Inula crithmoides L.). Upon in situ electrochemical generation of reactive oxygen species (ROS) the reactivity with such species was monitored using voltammetric signals associated to the oxidation of polyphenolic components of the plants. A simple kinetic model based on second-order reaction between ROS and polyphenolic components is applied to electrochemical data yielding apparent rate constants which can be correlated with the…

Intravital fluorescence microscopy for the study of leukocyte interaction with platelets and endothelial cells

1999

Publisher Summary This chapter introduces the techniques of intravital microscopy as a tool to study the microcirculation in intact animals under conditions of oxidative stress. Intravital fluorescence microscopy can be performed with almost all types of epiillumination microscopes available. The introduction of fluorescent dyes and refined epiillumination techniques has significantly advanced the possibilities of intravital microscopic studies of the liver microcirculation, including quantitative analyses of both circulatory parameters and cellular mechanisms. Using appropriate dyes, intravital microscopy allows the study of (1) microvascular perfusion, (2) leukocyte-endothelial cell inter…

Exercise-Induced Activation and Translocation of αB-Crystallin in Skeletal Muscle Depends upon Fiber Type and Oxidative Stress

2016

Alpha B-crystallin (CRYAB) is a member of the small heat shock proteins implicated in various biological functions, particularly in skeletal muscle tissue [1], where it results to be modulated following exercise-induced reactive oxygen species (ROS) [2]. In this work we aimed to analyse the CRYAB response to acute exercise with respect muscle fiber composition and to identify the underlying molecular mechanism by the utilization of the C2C12 “in vitro” cellular model. Our results highlighted as acute exercise determines a specific increase of phospho-CRYAB both in the red, but not white, gastrocnemius (GS), with an higher amount of oxidative and oxidative-glycolytic fibers, and in soleus (S…

Oxidative stress and mitochondrial failure in the pathogenesis of glaucoma neurodegeneration

2015

This review focuses on oxidative stress and mitochondrial failure for understanding mechanisms of optic nerve damage in primary open-angle glaucoma. The chapter shows scientific evidence for the role of mitochondrial disbalance and reactive oxygen species in glaucoma neurodegeneration. Mitochondria regulate important cellular functions including reactive oxygen species generation and apoptosis. Mitochondrial alterations result from a wide variety of damaging sources. Reactive oxygen species formed by the mitochondria can act as signaling molecules, inducing lipid peroxidation and/or excitotoxicity with the result of cell lesion and death. Antioxidants may help to counteract oxidative stress…

Reactive oxygen species involvement in apoptosis and mitochondrial damage in Caco-2 cells induced by enniatins A, A1, B and B1

2013

The cytotoxic effects, the generation of reactive oxygen species (ROS) and lipid peroxidation (LPO) as well as the cell cycle disruption, the induction of apoptosis and changes in mitochondrial membrane potential (ΔΨm) as a function of increasing time have been determined in human colorectal adenocarcinoma (Caco-2) cells after exposure to enniatins (ENs) A, A₁, B and B₁. IC₅₀ values obtained by the MTT and Neutral Red assay, after 24, 48 and 72 h of exposure ranged from 0.5±0.1 to >15 μM. A significant increase (p≤0.05) in ROS generation and LPO production, as determined by the fluorescent probe H2-DCFDA and TBARS method respectively, was observed for all mycotoxins tested at 3.0 μM concent…

The protective effects of melanoidins in adriamycin-induced oxidative stress in isolated rat hepatocytes

2004

The importance of the antioxidants contained in foods is well recognized both for preserving the foods themselves and for supplying essential antioxidants in vivo. Among these, the melanoidins formed during food processing and storage represent a significant part of our diet, with an average intake of several grams per day. Melanoidins exhibit antioxidant properties in vitro through their protective effect against reactive oxygen species. Here we investigated the protective effect of the model glucose–glycine melanoidins on oxidative stress induced by adriamycin in hepatocytes isolated from rats. The study was performed by examining cell toxicity (lactate dehydrogenase) release in the mediu…

Glutathione-dependent defence system and monooxygenase enzyme activities in Arctic charr Salvelinus alpinus (L.) exposed to ozone

2000

Abstract One of the major obstacles of the increasing usage of ozone in aquaculture is the lack of relevant risk assessment in culture conditions. Before the apparent advantages of ozonation can be utilised efficiently, the safety margins and biological basis of ozone toxicity should be assessed. In this research, 1-year-old Arctic charr ( Salvelinus alpinus (L.)) were exposed to an ozone concentration high enough to inactivate Aeromonas sp. bacteria in freshwater, but too low to be directly lethal to the fish themselves. The effects of ozone exposure on the activity of glutathione-dependent antioxidant enzymes and monooxygenase reactions were studied in blood and in liver. The fish were ac…

Formation of covalent di-tyrosine dimers in recombinant α-synuclein

2015

Parkinson's disease is associated with fibril deposition in the diseased brain. Misfolding events of the intrinsically disordered synaptic protein α-synuclein are suggested to lead to the formation of transient oligomeric and cytotoxic species. The etiology of Parkinson's disease is further associated with mitochondrial dysfunction and formation of reactive oxygen species. Oxidative stress causes chemical modification of native α-synuclein, plausibly further influencing misfolding events. Here, we present evidence for the spontaneous formation of covalent di-tyrosine α-synuclein dimers in standard recombinant protein preparations, induced without extrinsic oxidative or nitrative agents. The…

2013

Re-canalization of cerebral vessels in ischemic stroke is pivotal to rescue dysfunctional brain areas that are exposed to moderate hypoxia within the penumbra from irreversible cell death. Goal of the present study was to evaluate the effect of moderate hypoxia followed by reoxygenation (MHR) on the evolution of reactive oxygen species (ROS) and blood-brain barrier (BBB) integrity in brain endothelial cells (BEC). BBB integrity was assessed in BEC in vitro and in microvessels of the guinea pig whole brain in situ preparation. Probes were exposed to MHR (2 hours 67-70 mmHg O2, 3 hours reoxygenation, BEC) or towards occlusion of the arteria cerebri media (MCAO) with or without subsequent repe…