New achievement of Chinese research team: puffer fish poisoning will have medicine to save! Attachment: what are the symptoms of puffer fish poisoning? How long is the incubation period?

It was learned from Nankai University on May 28 that the research team led by the State key Laboratory of Pharmaceutical Chemistry Biology of Nankai University successfully "deciphered" the two target genes of tetrodotoxin by using haploid neural stem cells of monkeys, and through gene knockout tetrodotoxin resistance to tetrodotoxin. This study will make puffer fish poisoned "have medicine to save". The results are published online in the latest issue of the academic journal Development in the field of stem cell and neural development.

Puffer fish is delicious, but tetrodotoxin is so poisonous that it often makes accidental eaters die instantly. Its action target and toxicological mechanism are still unknown. Previous studies have suggested that tetrodotoxin is a kind of neurotoxoid, and its toxicology may play a toxic role in blocking sodium and potassium channels in nerve cells. So, can monkey haploid neural stem cells be used to screen the "action point" of tetrodotoxin on the nervous system?

Leading the team to proceed in reverse, with the help of the new haploid cell tool culture technology in recent years, by adopting the initial pluripotent culture system, monkey haploid embryonic stem cells have better haploid maintenance and cell survival in the process of in vitro differentiation, and monkey haploid neural stem cells with in vitro proliferation ability have been obtained for the first time in the world. In the experiment, the researchers then carried out a high-throughput whole-genome random mutation of the monkey haploid neural stem cells, and the mutated cell lines were tested for tetrodotoxin poisoning. Finally, bioinformatics analysis and gene editing experiments confirmed that the key target groups of tetrodotoxin were B4GALT6 and SCN5A. From a genetic point of view, as a result of directly finding the specific functional genes that perform toxic functions, in theory, as long as these target genes are knocked out, nerve cells can acquire tetrodotoxin resistance.

According to reports, because monkeys and other primates and human genetic similarity is very high. For humans, finding the target gene can detoxify it by taking genetic inhibitors. It also means that in the near future, people who have been poisoned by puffer fish will no longer be hopeless.

Introduction of puffer fish

Puffer fish is the general name of the bony fish family, commonly known as puffer fish. (note: there is a mistake in the name of puffer fish, but it is widely used. Puffer fish can also refer to a freshwater mammal. Puffer fish eaten in China have been born in rivers since ancient times. They are named "river dolphins" because they chirp like pigs when they catch water. In addition, there are "bubble fish", "belly fish", "puffer fish", "gas drum fish" (Jiangsu and Zhejiang), "good fish" (Guangdong), "chicken hug" (Guangdong), "tortoise fish" (Guangxi), "street fish" (read in Minnan dialect) (Fujian), "wax head" (Hebei), "boat fish" and so on. It was called "lungfish" in ancient times.

Tetrodotoxin is mainly distributed in ovary and liver, followed by kidney, blood, eyes, Gill and skin, while testes and muscles are non-toxic. If the fish dies for a long time, the visceral toxin dissolves into the body fluid and gradually seeps into the muscle. The amount of its toxin often varies from season to season. The period of ovarian development is from February to May every year, and the toxicity is strong. After spawning from June to July, the ovary degenerates and the toxicity decreases. The toxicity of the liver is the strongest in the spring spawning period. Therefore, when eating puffer fish fresh in late spring and early summer, special care should be taken. We must choose live fish and strictly remove the internal organs so as to avoid poisoning.

Symptoms and incubation period of puffer fish poisoning

The incubation period was 0.5 to 3 hours. Gastrointestinal symptoms such as nausea, vomiting, diarrhea, abdominal pain, sensory and motor dysfunction, numbness of lips, tip of tongue, limb and body numbness and limb weakness occurred first. Blepharoptosis, ataxia, hoarseness, severe cases may have dyspnea, arrhythmia and conduction block, coma; finally, respiratory and circulatory failure, tetrodotoxin detoxification and excretion in the human body faster, if not dead after 8 hours can recover.