Glutathione Depletion Disrupts Redox Homeostasis in an Anoxia-Tolerant Invertebrate.

The upregulation of endogenous antioxidants is a widespread phenomenon in animals that tolerate hypoxia/anoxia for extended periods. The identity of the mobilized antioxidant is often context-dependent and differs among species, tissues, and stresses. Thus, the contribution of individual antioxidants to the adaptation to oxygen deprivation remains elusive.

Commentary: Ultraviolet radiation triggers "preparation for oxidative stress" antioxidant response in animals: Similarities and interplay with other stressors.

Preparation for oxidative stress (POS), i.e., the upregulation of endogenous antioxidants, is a widespread response of animals exposed to extreme conditions.

Circular Estimate Method (CEM) - a Simple Method to Estimate Culture Densities in Liquid Medium.

Background: Nematodes are used in many different fields of science, including environmental and biomedical research. Counting and/or estimating nematode numbers is required during research. Although being one of the most common procedures, this apparently simple task is a time-consuming process, prone to errors and concerns regarding procedure, reliability, and accuracy.

The connection between oxidative stress and estivation in gastropods and anurans.

In situations of food and water deprivation associated with unfavorable environmental conditions, a number of animal species undergo estivation. This state of locomotor inactivity involves a drastic reduction in the metabolic rate, allowing the estivator to survive long periods of adverse situations. However, the arousal from dormancy causes a rapid increase in oxygen consumption, which may elevate the production of oxygen radicals.

Antioxidant responses in different body regions of the polychaeta Laeonereis acuta (Nereididae) exposed to copper.

Antioxidant enzymes, total antioxidant capacity (TOSC) and concentration of reactive oxygen species (ROS) were measured in anterior (A), middle (M) and posterior (P) body regions of Laeonereis acuta after copper (Cu; 62.5 microg/l) exposure. A catalase (CAT) activity gradient observed in control group (lowest in A, highest in P) was not observed in Cu exposed group.

Toxicological responses in Laeonereis acuta (annelida, polychaeta) after arsenic exposure.

Several environmental pollutants, including metals, can induce oxidative stress. So, the objective of this study was to evaluate the effects of arsenic (As(III), as As(2)O(3)) on the antioxidant responses in the polychaete Laeonereis acuta. Worms were exposed to two environmentally relevant concentrations of As, including the highest previously allowed by Brazilian legislation (50 microg As/l).

Pollution biomarkers in estuarine animals: critical review and new perspectives.

In this review, recent developments in monitoring toxicological responses in estuarine animals are analyzed, considering the biomarker responses to different classes of pollutants. The estuarine environment imposes stressful conditions to the organisms that inhabit it, and this situation can alter their sensitivity to many pollutants. The specificity of some biomarkers like metallothionein tissue concentration is discussed in virtue of its dependence on salinity, which is highly variable in estuaries.

Antioxidant responses and reactive oxygen species generation in different body regions of the estuarine polychaeta Laeonereis acuta (Nereididae).

The aim of this study was to analyze the total antioxidant capacity (TOSC), generation of reactive oxygen species (ROS) and lipid peroxidation (LPO) in the different body regions of the estuarine polychaeta Laeonereis acuta (Nereididae) sampled at non-polluted (NOPOL) and polluted (POL) sites from Lagoa dos Patos (Southern Brazil). Organisms collected at POL during summer showed similar (p>0.05) TOSC values along the body, but worms collected at NOPOL presented higher (p<0.