Okadaic Acid and Dinophysistoxins 11) are produced by a number of dinoflagellates, and they cause diarrhea. Because exposures often result from eating contaminated shellfish, the syndrome has been called diarrhetic shellfish poisoning.
What is domoic acid poisoning?
Domoic acid (DA) is a kainic acid-type neurotoxin that causes amnesic shellfish poisoning (ASP). It is produced by algae and accumulates in shellfish, sardines, and anchovies. When sea lions, otters, cetaceans, humans, and other predators eat contaminated animals, poisoning may result.
Is okadaic acid a neurotoxin?
Okadaic acid is a potent neurotoxin and phosphatase inhibitor from dinoflagellate black sponges and is associated with seafood poisonings.
What condition is associated with consuming fish shellfish contaminated with okadaic acid toxins?
Diarrhetic shellfish poisoning (from okadaic acid and dinophysistoxins) is generally associated with the consumption of bivalve molluscan shellfish with outbreaks being reported worldwide.
Where does okadaic acid come from?
Okadaic acid is a polycyclic ether that is produced by several species of dinoflagellates, and is known to accumulate in both marine sponges and shellfish. A polyketide, polyether derivative of a C38 fatty acid, it is one of the primary causes of diarrhetic shellfish poisoning (DSP).
Where does saxitoxin come from?
Saxitoxin is produced by the dinoflagellates Gonyaulax, Alexandrium, Gymnodinium, and Pyrodinium. Similar to tetrodotoxin, saxitoxin binds to voltage-gated sodium channels within cell membranes, inhibiting membrane depolarization and blocking proliferation of action potentials.
Is domoic acid a toxin?
Domoic acid is a marine biotoxin toxin called Amnesic Shellfish Poison (ASP) which is produced by the diatom Pseudo-nitzschia sp., a type of naturally occurring microscopic algae. Shellfish eat these algae and can retain the toxin. People can become ill from eating shellfish contaminated with Amnesic Shellfish Poison.
How long does ciguatera poisoning last?
Irregular heart rhythms and low blood pressure may also be experienced. Ciguatera poisoning symptoms typically resolve within several days, but may last up to 4 weeks. The symptoms of ciguatera poisoning may resemble other medical conditions.
What effect does neurotoxic shellfish poisoning have on humans?
NSP involves a cluster of gastrointestinal and neurological symptoms: nausea and vomiting, paresthesias of the mouth, lips and tongue as well as distal paresthesias, ataxia, slurred speech and dizziness. Neurological symptoms can progress to partial paralysis; respiratory distress has been recorded.
How long does diarrhetic shellfish poisoning last?
As the name suggests, this syndrome manifests itself as intense diarrhea and severe abdominal pains. Nausea and vomiting may sometimes occur too. DSP and its symptoms usually set in within about half an hour of ingesting infected shellfish, and last for about one day.
How do you dissolve okadaic acid?
Okadaic acid is complex hydrophobic polyether that comes as a white crystalline solid. It is readily soluble in many organic solvents and degrades in acid or base. Although soluble in DMSO and a number of organic solvents, the recommended solvent is N,N-dimethylformamide (DMF).
How much saxitoxin is lethal?
The oral LD50 for humans is 5.7 μg/kg, therefore approximately 0.57 mg of saxitoxin (1/8th of a medium-sized grain of sand) is lethal if ingested and the lethal dose by injection is about 1/10th of that (approximately 0.6 μg/kg).
What is okadaic acid (OA)?
Okadaic acid (OA), a potent polyether marine toxin, accumulates in the digestive glands of marine mollusks and therefore can severely threaten the health of humans after ingestion of contaminated shellfish.
Can okadaic acid and mycotoxins aggravate diarrhetic shellfish poisoning?
While diarrhetic shellfish poisoning (DSP) from okadaic acid and analogues in many parts of the world is considered to be a comparatively minor seafood toxin syndrome, our human cell model studies suggest that synergisms with certain mycotoxins may aggravate human health impacts, depending on the concentrations.
Is algal toxin okadaic acid cytotoxic?
The current study assesses the cytotoxicity of the algal toxin okadaic acid, shellfish, and dust storm-associated mycotoxins alone or in combination on human intestinal (HT-29) and neuroblastoma (SH-SY5Y) cell lines.
How long does okadaic acid take to work?
One of these species is Halichondria okadai, from which okadaic acid is named. The symptoms of diarrhea and vomitting start within 3 to 12 hours after ingestion of tainted shellfish, with a frequency of up to 12 times per day.
