title: Caribbean yellow band disease compromises the activity of catalase and glutathione S-transferase in the reef-building coral Orbicella faveolata exposed to anthracene.
abstract: Healthy and diseased corals are threatened by different anthropogenic sources, such as pollution, a problem expected to become more severe in the near future. Despite the fact that coastal pollution and coral diseases might represent a serious threat to coral reef health, there is a paucity of controlled experiments showing whether the response of diseased and healthy corals to xenobiotics differs. In this study, we exposed healthy and Caribbean yellow band disease (CYBD)-affected Orbicella faveolata colonies to 3 sublethal concentrations of anthracene to test if enzymatic responses to this hydrocarbon were compromised in CYBD-affected tissues. For this, a 2-factorial fully orthogonal design was used in a controlled laboratory bioassay, using tissue condition (2 levels: apparently healthy and diseased) and pollutant concentration (4 levels: experimental control, 10, 30 and 100 ppb concentration) as fixed factors. A permutation-based ANOVA (PERMANOVA) was used to test the effects of condition and concentration on the specific activity of 3 enzymatic biomarkers: catalase, glutathione S-transferase, and glutathione peroxidase. We found a significant interaction between the concentration of anthracene and the colony condition for catalase (Pseudo-F = 3.84, df = 3, p < 0.05) and glutathione S-transferase (Pseudo-F = 3.29, df = 3, p < 0.05). Moreover, our results indicated that the enzymatic response to anthracene in CYBD-affected tissues was compromised, as the activity of these enzymes decreased 3- to 4-fold compared to healthy tissues. These results suggest that under a potential scenario of increasing hydrocarbon coastal pollution, colonies of O. faveolata affected with CYBD might become more vulnerable to the deleterious effects of chemical pollution.
authors.affiliation: Universidad Simón Bolívar, Departamento de Estudios Ambientales, Laboratorio de Ecología Experimental, Apdo. 89000, Caracas, Venezuela.
authors.forename: Luis Miguel
authors.initials: LM
authors.lastname: Montilla
authors.forename: Ruth
authors.initials: R
authors.lastname: Ramos
authors.forename: Elia
authors.initials: E
authors.lastname: García
authors.forename: Aldo
authors.initials: A
authors.lastname: Cróquer
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000201:enzymology*; D000873:Anthracenes / Q000633:toxicity*; D017691:Caribbean Region; D002374:Catalase / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D005982:Glutathione Transferase / Q000378:metabolism*
chemical_list: D000873:Anthracenes; D002374:Catalase; D005982:Glutathione Transferase; C034020:anthracene