HRMAS NMR as a tool to study metabolic responses in heart clam Ruditapes decussatus exposed to Roundup®

Abstract

The essence of this study was to investigate the metabolic responses of heart tissues of carpet-shell clam Ruditapes decussatus after exposure to two doses (0.2 and 1 g/L) of Roundup(®) during 24 and 72 h. The main metabolic changes after Roundup(®) exposure were related to disturbance in energy metabolism and metabolic biomarkers such as alanine, succinate, acetate and propionate, suggesting the occcurence of anaerobiosis and the impairment of oxydative metabolism. Results showed also that peak intensities of amino acids used as biomarker of anaerobiosis in molluscs are time and dose dependent. In the opposite, phosphoarginine and ATP level are dependent to Roundup(®) concentration rather than to the time of exposure. We suggest that changes in energy demands require adjustements in the forward arginine kinase reaction rate. Therefore, the results demonstrate the high applicability of HRMAS NMR to elucidate the mechanism of toxicity of Roundup(®). In addition, (31)P HRMAS NMR appeared to be an effective and simple method to follow bioaccumulation of Roundup(®) formulation.