Tetrodotoxin, dangerous toxin in puffer fish

Tetrodotoxin - dangerous toxin in puffer fish Group : Enkhbayar Batsukh Hoàng Thị Giang Nguyễn Việt Hà (team leader) Vũ Thị Hạnh Contents I Introduction II Mechanism of Action III Symptoms and treatments IV Conclusion I Introduction On 7th Sep 1774, Captain James Cook recorded his crew eating some local tropic fish, then feeding the remains to the pigs on board The crew experienced numbness and shortness of breath, while the pigs were all dead the next morning What you think happened to them??  Tetrodotoxin (TTX) is one of the most potent neurotoxin I Introduction Structure  Properties • Molecular formula: C11H17N3O8 • Molecular Weight: 319.2706 (g/mol) I Introduction  IUPAC name: Octahydro-12-(hydroxymethyl)-2-imino5,9:7,10a-dimethano-10aH-[1,3] dioxocino[6,5-d]pyrimidine-4,7,10,11,12-pentol  Other names: anhydrotetrodotoxin 4-epitetrodotoxin tetrodonic acid TTX I Introduction Properties  White crystalline solid, odourless Heat stable Soluble in dilute acetic or sulfuric acid Limited solubility in ethanol and ether Insoluble in organic solvents I Introduction Source  Mostly found in puffer fish and several other animals like blue-ringed octopus, rough-skinned newt  Made by relatively common marine bacteria, specifically Pseudoalteromonas haloplanktis tetraodonis, that associates with these animals II Mechanism of Action Pathway: oIngestion oInjection oInhalation oThrough abraded skin II Mechanism of Action Conduction of nerve impulses along nerve fibers and axons II Mechanism of Action TTX molacular II Mechanism of Action  When Na+ Channels are blocked, an action potential can not be initiated and muscles can not contract This is important for things like… Breathing II.Mechanism of actions Toxicity potential depends on what part of the puffer fish you eat! - High concentration mainly in liver! Case study in animals: TTX from puffer fish from the Red Sea in Egypt => LD50 (gonad) = 6.26mg/kg LD50 (skin) = 27.9 mg/kg Health risk assessment : LD50(mg/kg, rat, oral) = 0,1 LD50(microgram/kg, human) =2    Lagocephalus collected III.Symptoms and treatments Symptoms Time course : - Rapid onset (10 to 45 min) and delayed onset (3 to hours) - Death usually occur within to hours Symptoms of TTX poisoning Stage - Slight numbness of lips and tongue immediately Stage - Increasing paresthesia in face and extremities - Sensations of lightness and floating Stage - Increasing paralysis - Convulsions, mental impairment, cardiac dysfunction Stage - Central nervous system (CNS) dysfunction - Complete paralysis - Death Treatment At home: - let patients vomit but prevent from choking, - take activated charcoal with the dose: Adults: mixture of 30g + 250ml water Children 1-12 years of age: mixture of 25g + 100-200ml water Children under year: oral 1g/kg weight mixed with 50ml of water Then transfer immediately to a hospital IV.Conclusion TTX is contained in many various kinds of marine species => information about them is essential since there is no antidote We can be exposed to this violent toxin by ways, but in most cases, ingestion was the only common In the scientific studies, it is proven that gonads are more lethal than skin of puffer fish IV.Conclusion The time effect is acute Death may occur within the first to hours And it causes serious pain => Recommendation a b Should not use puffer fish for food Should know and remember the first aid of TTX poisoning to protect yourself in case of accidental exposure Thank you for your listening Q & A sections [...]... violent toxin by 4 ways, but in most cases, ingestion was the only common In the scientific studies, it is proven that gonads are more lethal than skin of puffer fish IV.Conclusion 3 The time effect is acute Death may occur within the first 4 to 6 hours And it causes serious pain => Recommendation a b Should not use puffer fish for food Should know and remember the first aid of TTX poisoning to protect... blocked, an action potential can not be initiated and muscles can not contract This is important for things like… Breathing II.Mechanism of actions Toxicity potential depends on what part of the puffer fish you eat! - High concentration mainly in liver! Case study in animals: TTX from puffer fish from the Red Sea in Egypt => LD50 (gonad) = 6.26mg/kg LD50 (skin) = 27.9 mg/kg Health risk assessment... and treatments 1 Symptoms Time course : - Rapid onset (10 to 45 min) and delayed onset (3 to 8 hours) - Death usually occur within 4 to 6 hours Symptoms of TTX poisoning Stage 1 - Slight numbness of lips and tongue immediately Stage 2 - Increasing paresthesia in face and extremities - Sensations of lightness and floating Stage 3 - Increasing paralysis - Convulsions, mental impairment, cardiac dysfunction... prevent from choking, - take activated charcoal with the dose: Adults: mixture of 30g + 250ml water Children 1-12 years of age: mixture of 25g + 100-200ml water Children under 1 year: oral 1g/kg weight mixed with 50ml of water Then transfer immediately to a hospital IV.Conclusion 1 2 TTX is contained in many various kinds of marine species => information about them is essential since there is no... to 6 hours And it causes serious pain => Recommendation a b Should not use puffer fish for food Should know and remember the first aid of TTX poisoning to protect yourself in case of accidental exposure Thank you for your listening Q & A sections