One-year monitoring of core biomarker and digestive enzyme responses in transplanted zebra mussels (Dreissena polymorpha)

Abstract

A 12-month active biomonitoring study was performed in 2008-2009 on the Vesle river basin (Champagne-Ardenne, France) using the freshwater mussel Dreissena polymorpha as a sentinel species; allochthonous mussels originating from a reference site (Commercy) were exposed at four sites (Bouy, Sept-Saulx, Fismes, Ardre) within the Vesle river basin. Selected core biomarkers (acetylcholinesterase (AChE) activity, glutathione-S transferase (GST) activity, metallothionein concentration), along with digestive enzyme activities (amylase, endocellulase) and energy reserve concentrations (glycogen, lipids), were monitored throughout the study in exposed mussels. At the Fismes and Ardre sites (downstream basin), metallic and organic contamination levels were low but still high enough to elicit AChE and GST activity induction in exposed mussels (chemical stress); besides, chemical pollutants had no apparent deleterious effects on mussel condition. At the Bouy and Sept-Saulx sites (upstream basin), mussels obviously suffered from adverse food conditions which seriously impaired individual physiological state and survival (nutritional stress); food scarcity had however no apparent effects on core biomarker responses. Digestive enzyme activities responded to both chemical and nutritional stresses, the increase in energy outputs (general adaptation syndrome-downstream sites) or the decrease in energy inputs (food scarcity-upstream sites) leading to mid- or long-term induction of digestive carbohydrase activities in exposed mussels (energy optimizing strategy). Complex regulation patterns of these activities require nevertheless the use of a multi-marker approach to allow data interpretation. Besides, their sensitivity to natural confounding environmental factors remains to be precised.

Exposure of marine mussels Mytilus spp. to polystyrene microplastics: Toxicity and influence on fluoranthene bioaccumulation

“…Micro-PS exposure affected mussels physiology 6.3.1. Modulation of digestion and energy metabolism The induction of glycolysis and digestive activity upon micro-PS exposure may sign increased energy requirements in response to the implementation of anti-oxidant and detoxification processes (Palais et al, 2012). This mechanism would allow the animal to cope with experimental stress and maintain homeostasis, as suggested in a study conducted by Van Cauwenberghe et al (2015) who demonstrated a 25% increase in energy consumption in mussels exposed to micro-PS for 14 days in comparison with controls.…”

Ecological relevance of biomarkers in monitoring studies of macro-invertebrates and fish in Mediterranean rivers

“…cellulase, glucosidase, and amilase) (Dedourge-Geffard et al, 2009;Palais et al, 2012). For example, changes in these enzymatic responses preceded mortality (b7 days later) in zebra mussels (D. polymorpha) or amphipods (Gammarus fossarum) exposed to metals in laboratory (Dedourge-Geffard et al, 2009) and field conditions (Palais et al, 2012). Also, these enzymatic activities were found to be affected before the target sentinel experienced growth and body condition alterations (Hyne and Maher, 2003).…”

Does zebra mussel (Dreissena polymorpha) represent the freshwater counterpart of Mytilus in ecotoxicological studies? A critical review

“…Significant variations in condition index, GST activity and in genotoxicity parameters (MN and SCGE assay) were noted in mussels transplanted downstream compared to upstream. A 12-month ABM performed on the Vesle river basin (France) transplanting D. polymorpha specimens in four sites with different pollution levels pointed out changes in response of AChE, GST, metallothionein, as well as digestive enzyme activities (amylase, endocellulase) and energy reserve concentrations (Palais et al, 2012). According to Smolders et al (2002), all the studies mentioned above highlighted the use of transplanted mussels as a sensitive and easily applicable tool that can be used to assess water quality, pollution and subsequent recovery through selfpurification in field situations.…”