Utilization of Mytilus digestive gland cells for the in vitro screening of potential metabolic disruptors in aquatic invertebrates

In this work, primary cell cultures from the digestive gland of the bivalve Mytilus galloprovincialis were utilized to investigate the effects of model EDs (bisphenol A (BPA) and perfluorooctane sulphonate (PFOS)) on lipid homeostasis. Both compounds (at 24 and 3 h of exposure) increased intracellular lipid and tryglyceride-TAG content, with strongest effects of PFOS at 10− 7 M. Acyl-CoA oxidase activity was unaffected, whereas some changes in the activity of glycolytic, antioxidant/biotransformation enzymes were observed; however, no clear relationship was found with lipid accumulation. Evaluation of mitochondrial membrane potential Δψm and determination of extracellular TAG content indicate that PFOS interferes with mitochondrial function and lipid secretion, whereas BPA mainly affects lipid secretion. Experiments with specific inhibitors showed that activation of PI-3 kinase and extracellularly regulated mitogen-activated protein kinase (ERK MAPK) plays a key role in mediating lipid accumulation. Mussel digestive gland cells represent a simple in vitro model for screening the metabolic effects of EDs in marine invertebrates.