title: Could molecular effects of Caulerpa racemosa metabolites modulate the impact on fish populations of Diplodus sargus?
abstract: The green alga Caulerpa racemosa is a non-native, invasive species in the Mediterranean, and an important stressor for several native organisms. The algal capacity to produce secondary metabolites has been suggested to modulate success of the C. racemosa invasion, although many of potentially involved biological pathways still remain unexplored. In this respect, the aim of the present study was to investigate some molecular and cellular effects in the white seabream Diplodus sargus, an ecologically key species, which included the alien C. racemosa in its diet. Organisms were sampled in 2 seasonal periods from 3 locations of Southern Italy, each characterized by different levels of algal abundance. The level of caulerpin, one of the main secondary algal metabolites, in fish tissues has been used as an indicator of the trophic exposure to the seaweed and related with molecular and cellular responses. Chemical analyses indicated that fish from invaded sites can accumulate caulerpin, with liver concentrations ranging from a few up to hundreds of μg/g. Biomarkers analyses revealed only limited alterations of the main antioxidant defences, such as glutathione reductase and levels of glutathione; on the other hand, increased enzymatic activities of cytochrome P450, glutathione S-transferases and acyl CoA oxidase, as well as enhanced gene transcription for peroxisome proliferator-activated receptor alpha, cytochrome P4501A and vitellogenin 1 were observed in fish more exposed to C. racemosa as indicated by liver concentrations of caulerpin higher than 50 μg/g. Despite a direct molecular relationship with this algal metabolite could not be established, our results suggest that a C. racemosa enriched diet can modulate biotransformation and fatty acids metabolism of D. sargus. Assessing whether similar effects represent short- or long-term effects will be of crucial importance to understand consequences on the general health status and reproductive performance of exposed key fish species in the Mediterranean region.
authors.affiliation: Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona, Italy. Electronic address: s.gorbi@univpm.it.
authors.forename: S
authors.initials: S
authors.lastname: Gorbi
authors.affiliation: Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: M E
authors.initials: ME
authors.lastname: Giuliani
authors.affiliation: Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Pittura
authors.affiliation: Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: G
authors.initials: G
authors.lastname: d'Errico
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, Lecce, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Terlizzi
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, Lecce, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Felline
authors.affiliation: Istituto di Chimica Biomolecolare, CNR, Naples, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Grauso
authors.affiliation: Istituto di Chimica Biomolecolare, CNR, Naples, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Mollo
authors.affiliation: Istituto di Chimica Biomolecolare, CNR, Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Cutignano
authors.affiliation: Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Regoli
mesh_terms: D000818:Animals; D046068:Caulerpa / Q000737:chemistry*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism; D004781:Environmental Exposure; D004784:Environmental Monitoring; D005260:Female; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D020387:Food Chain; D007211:Indoles / Q000494:pharmacology*; D058865:Introduced Species; D007558:Italy; D008099:Liver / Q000378:metabolism; D008969:Molecular Sequence Data; D047493:PPAR alpha / Q000235:genetics / Q000378:metabolism; D010473:Perciformes / Q000235:genetics* / Q000378:metabolism*; D012621:Seasons; D017422:Sequence Analysis, DNA; D014819:Vitellogenins / Q000235:genetics / Q000378:metabolism
chemical_list: D029941:Fish Proteins; D007211:Indoles; D047493:PPAR alpha; D014819:Vitellogenins; C000392:caulerpin; D003577:Cytochrome P-450 Enzyme System
keywords: Biological invasions; Biomarkers; Caulerpa racemosa; Diplodus sargus; Molecular effects