title: Caffeine impacts in the clam Ruditapes philippinarum: Alterations on energy reserves, metabolic activity and oxidative stress biomarkers.
abstract: Caffeine is known to be one of the most consumed psychoactive drugs. For this reason, caffeine is continuously released into the environment with potential impacts on inhabiting organisms. The current study evaluated the biochemical alterations induced in the clam species Ruditapes philippinarum after exposure for 28 days to caffeine (0.5, 3.0 and 18.0 μg/L). The results obtained showed that, with the increasing caffeine concentrations, an increase in clams defense mechanisms (such as antioxidant and biotransformation enzymes activity) was induced which was accompanied by an increase in protein content. Nevertheless, although an increase on defense mechanisms was observed, clams were not able to prevent cells from lipid peroxidation that increased with the increase of caffeine concentration. Furthermore, with the increase of exposure concentrations, clams increased their metabolic activity (measured by electron transport activity), reducing their energy reserves (glycogen content), to fight against oxidative stress. Overall, the present study demonstrated that caffeine may impact bivalves, even at environmentally relevant concentrations, inducing oxidative stress in organisms. The present study is an important contribution to address knowledge gaps regarding the impacts of long-term exposures to pharmaceuticals since most of the studies assessed the effects after acute exposures, most of them up to 96 h.
authors.affiliation: Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal.
authors.forename: Diogo
authors.initials: D
authors.lastname: Cruz
authors.affiliation: Department of Biology & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal.
authors.forename: Ângela
authors.initials: Â
authors.lastname: Almeida
authors.affiliation: Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal.
authors.forename: Vânia
authors.initials: V
authors.lastname: Calisto
authors.affiliation: Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal.
authors.forename: Valdemar I
authors.initials: VI
authors.lastname: Esteves
authors.affiliation: BAM Federal Institute for Materials Research and Testing, 12205, Berlin, Germany.
authors.forename: Rudolf J
authors.initials: RJ
authors.lastname: Schneider
authors.affiliation: Department of Geography, University of Victoria, National Water Research Institute, STN CSC, Victoria, BC, Canada.
authors.forename: Frederick J
authors.initials: FJ
authors.lastname: Wrona
authors.affiliation: Department of Biology & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal.
authors.forename: Amadeu M V M
authors.initials: AM
authors.lastname: Soares
authors.affiliation: Department of Biology & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal.
authors.forename: Etelvina
authors.initials: E
authors.lastname: Figueira
authors.affiliation: Department of Biology & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal. Electronic address: rosafreitas@ua.pt.
authors.forename: Rosa
authors.initials: R
authors.lastname: Freitas
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D015415:Biomarkers / Q000378:metabolism*; D001711:Biotransformation; D049872:Bivalvia / Q000187:drug effects* / Q000378:metabolism; D002110:Caffeine / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D004579:Electron Transport; D004784:Environmental Monitoring; D004798:Enzymes / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D015227:Lipid Peroxidation / Q000187:drug effects; D015999:Multivariate Analysis; D018384:Oxidative Stress / Q000187:drug effects*; D010100:Oxygen / Q000737:chemistry; D011174:Portugal; D012623:Seawater; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D004798:Enzymes; D014874:Water Pollutants, Chemical; D002110:Caffeine; D010100:Oxygen
keywords: Bivalves; Environmentally relevant concentrations; Long-term exposure; Oxidative stress; Pharmaceuticals