Oxidative stress biomarkers in the gills of the bivalve <em>Mactra stultorum</em> exposed to acrylamide

Abstract

Acrylamide (ACR) is among the most deleterious pollutants in the environment and presents a serious risk to humans and ecosystems. The purpose of this study was to assess its effects when administered at different concentrations (5, 10 and 20 mg L–1) to evaluate antioxidant status in the gills of Mactra stultorum. Our results showed, after five days of treat­ment, an increase in malondialdehyde (MDA), lipid hydroperoxides (LOOH), advanced oxidation protein products (AOPP), reduced glutathione (GSH), ascorbic acid (Vit C) and metallothionein (MDA) levels in gills of treated clams compared with controls. Moreover, an increase in superoxide dismutase (SOD) and a significant decrease in glutathione peroxidase (GPx) activities were also observed. Acrylamide induced neurotoxicity, as evidenced by the inhibition of acetylcholinesterase (AChE) activity in a dose-dependent manner. Overall, our results indicated that oxidative stress may be considered one of the mechanisms behind acrylamide toxicity in bivalves, although the subject requires more research.

The potential adverse effects of acrylamide on the oxidative stress response, fatty acids profile, and histopathological aspect of the Mediterranean Holothuria forskali respiratory tree

“…Such findings agreed with our previous reports conducted on ACR-treated bivalves. 12,13 A wide range of cellular effects occuring due to lipid peroxidation may alter the membrane fatty acids (FAs) composition. Since FAs play a key role in organisms' metabolism, variations in their profiles are recently considered as one of the efficient tools to assess xenobiotics impact on several aquatic organisms.…”

“…It may cause various toxicity in fish models 10 . Recent studies have revealed that ACR exerts its toxic effects on aquatic organisms by inducing oxidative stress through excessive production of reactive oxygen species (ROS) 11–13 . Biological membranes are selectively permeable barriers enclosing cells.…”

“…Hence, lipids, especially fatty acids (FAs) with a high degree of instauration, such as long‐chain (≥C20) polyunsaturated fatty acids (PUFAs), are considered as substrates that mostly undergo oxidative attack 14 . Therefore, ACR exposure probably disturbs the cellular PUFAs content in bivalves 12,13 . Thus, the degree of instauration is modulated by the action of the desaturation and elongation enzymes mediating FA biosynthesis and metabolism.PUFAs such as arachidonic acid (ARA, 20:4n‐6), eicosapentaenoic acid (EPA, 20:5n‐3), and docosahexaenoic acid (DHA, 22:6n‐3) are essential lipids involved in many biological processes.…”

“…10 Recent studies have revealed that ACR exerts its toxic effects on aquatic organisms by inducing oxidative stress through excessive production of reactive oxygen species (ROS). [11][12][13] Biological membranes are selectively permeable barriers enclosing cells. They are composed principally of a lipid bilayer making them highly sensitive to ROS over a generation.…”

“…14 Therefore, ACR exposure probably disturbs the cellular PUFAs content in bivalves. 12,13 Thus, the degree of instauration is modulated by the action of the desaturation and elongation enzymes mediating FA biosynthesis and metabolism.PUFAs such as arachidonic acid (ARA, 20:4n-6), eicosapentaenoic acid (EPA, 20:5n-3), and docosahexaenoic acid (DHA, 22:6n-3) are essential lipids involved in many biological processes. As major constituents of membrane phospholipids, they can influence biological systems by different mechanisms acting as eicosanoids producers, substrates for enzymes, membranes flexibility units, and enter in the acylation of some proteins.…”