Data/hora: 06/06/2024 13:16:20

Provedor de dados: 	5	
País: 	France	
Título: 	Impact of the toxic dinoflagellate Alexandrium catenella on Pacific oyster reproductive output: application of flow cytometry assays on spermatozoa	
Autores: 	Le Goic, Nelly; Hegaret, Helene; Fabioux, Caroline; Miner, Philippe; Suquet, Marc; Lambert, Christophe; Soudant, Philippe.	
Data: 	2013-07	
Ano: 	2013	
Palavras-chave: 	Harmful algal bloom; Sperm quality; Cellular parameters; Flow cytometry; Pacific oyster; Crassostrea gigas; Alexandrium catenella.	
Resumo: 	The toxic dinoflagellate Alexandrium catenella recurrently blooms on the coasts of France and produces Paralytic Shellfish Toxins (PSTs) that accumulate in bivalves. These toxins can affect various physiological functions including reproduction. The present study aims to validate measurements of sperm viability, DNA content and mitochondrial membrane potential in Pacific oyster Crassostrea gigas using flow cytometry coupled with fluorescent markers, and to use these measurements to assess the cellular parameters of sperm from Pacific oysters exposed to A. catenella. These parameters may influence fertilization, embryogenesis and larval development in free-spawning shellfish. Sperm viability and DNA content estimation were assessed using SYBR-14, which only penetrates cells with intact membranes. Cell mortality was measured with propidium iodide (PI), which penetrates cells with membrane damage. Mitochondrial membrane potential, used as an estimate of mitochondrial function, was measured using IC-1 dye, which selectively enters into mitochondria and reversibly changes colour from green to orange as the membrane potential increases. To assess the effect of toxic algae on oyster sperm, broodstock (ripe oysters) were fed toxic (A. catenella) or non toxic (Heterocapsa triquetra) dinoflagellates at 250 cell ml(-1) for 9 days. After this exposure period, mature oysters were stripped and cellular responses of sperm analysed. Average DNA staining, as measured by SYBR-14, appeared lower and more variable in gametes from A. catenella-exposed oysters than in those from control oysters fed H. triquetra. Additionally, mitochondrial membrane potential of sperm from A. catenella-exposed oysters was significantly higher (1.5 fold) than that of sperm produced by oysters fed H. triquetra. Both the increase of mitochondrial membrane potential and the modification of DNA structure can be expected to impact spermatozoa ability to fertilize oocytes and could thus impact related reproductive processes.	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	http://archimer.ifremer.fr/doc/00157/26853/24982.pdf

DOI:10.1051/alr/2013047	
Editor: 	Edp Sciences S A	
Relação: 	http://archimer.ifremer.fr/doc/00157/26853/	
Formato: 	application/pdf	
Fonte: 	Aquatic Living Resources (0990-7440) (Edp Sciences S A), 2013-07 , Vol. 26 , N. 3 , P. 221-228	
Fonte: 	EDP Sciences, IFREMER, IRD 2013