Carboxyatractyloside (CATR) is a highly toxic diterpeneglycoside that inhibits the ADP/ATP translocase. It is about 10 times more potent than its analog atractyloside.[1] While atractyloside is effective in the inhibition of oxidative phosphorylation, carboxyatractyloside is considered to be more effective.[2] The effects of carboxyatractyloside on the ADP/ATP translocase are not reversed by increasing the concentration of adenine nucleotides, unlike its counterpart atractyloside.[2] Carboxyatractyloside behavior resembles bongkrekic acid while in the mitochondria.[2] Carboxyatractyloside is poisonous to humans as well as livestock, including cows[3] and horses.[4]
Symptoms of carboxyatractyloside poisoning may include abdominal pain, nausea and vomiting, drowsiness, palpitations, sweating and trouble breathing.[5] In severe cases, convulsions, liver failure and loss of consciousness may develop, which can lead to death.[5]
Carboxyatractyloside can be found in Xanthium species plants, including Xanthium strumarium.[6] Consumption of Xanthium containing the toxin led to the deaths of at least 19 people in Sylhet, Bangladesh during a period of food scarcity.[7] Along with atractyloside, it is also one of the main poisonous substances in the Atractylis gummifera thistle.[8]