Effect of okadaic acid on carpet shell clam (Ruditapes decussatus) haemocytes by in vitro exposure and harmful algal bloom simulation assays
- 382 Downloads
Okadaic acid (OA), produced by dinoflagellates during harmful algal blooms (HAB), belongs to the Diarrheic Shellfish Poisoning toxins that cause gastrointestinal symptoms in humans after consumption. In the present work, Ruditapes decussatus haemocytes were selected to evaluate the effect of OA on cell viability, enzymatic status and immune capacity through the measure by flow cytometry of apoptosis–cell death, non-specific esterase activity and phagocytosis. In order to compare different exposure conditions, two experiments were developed: in vitro exposure to OA and HAB simulation by feeding clams with the OA producer, Prorocentrum lima. Apoptosis was not OA dose-dependent and cell death increased in both assays. Phagocytosis of latex beads and esterase activity decreased in haemocytes incubated with OA. In contrast, esterases increased during the feeding with P. lima. Our results showed that OA and the simulated HAB caused damages on haemocyte functions and viability.
KeywordsApoptosis Flow cytometry Haemocyte Harmful algal bloom Okadaic acid
This work was funded by the project 07MMA013103PR. Consellería de Innovación e Industria, INCITE (Xunta de Galicia). Fernanda Flórez Barrós and Juan Fernández Tajes were supported by “Lucas Labrada” and “Angeles Alvariño” programs, respectively, both from Consellería de Innovación e Industria, Xunta de Galicia). We also would like to thank Dr. Gerardo Martínez for his help in OA determination.
- Biolojan C, Takai A. Inhibitory effect of a marine-sponge toxin okadaic acid on protein phosphatases. Specificity and kinetics. Biochem J. 1988;256:283–90.Google Scholar
- Blanco J, Moroño A, Fernández ML. Toxic episodes in shellfish produced by lipophilic phycotoxins: an overiew. Revista Galega de Recursos Mariños. 2005;1:1–70.Google Scholar
- da Silva PM, Hégaret H, Lambert C, Wikfors GH, Goïc NL, Shumway SE, et al. Immunological responses of the Manila clam (Ruditapes philippinarum) with varying parasite (Perkinsus olseni) burden, during a long-term exposure to the harmful alga, Karenia selliformis, and possible interactions. Toxicon. 2008;51:563–73.PubMedCrossRefGoogle Scholar
- Feng SY. Cellular defense mechanisms of oysters and mussels. Am Fish Soc Spec Publ. 1988;18:153–68.Google Scholar
- Narain AS. The amoebocytes of lamellibranch molluscs, with special reference to the circulating amoebocytes. Malacol Rev. 1973;6:1–12.Google Scholar