In the previous "Treatment of Autism, Is Acetylcysteine OK? In the article, Mr. Xi Lanhuajun painstakingly searched the relevant research and came to the conclusion that "whether the clinical application is effective or not has no clear conclusion", and I believe readers feel the same way.
Acetylcysteine can be said to be a rare cheap and safe medicine for conscience, and it is by no means a panacea for selling air. It would be a great misfortune if things just go away.
Fortunately, in June this year, a paper published by researchers at George Washington University in the United States brought vitality to the treatment of autism with acetylcysteine.
The life-saving grace of this research, let Broccoli Jun take it slowly.
At first, there was a theory that some autistic patients, especially their brain nerve cells, had defects in mitochondrial function, which caused a large number of free radicals produced by mitochondria to be unable to be removed in time, affecting mitochondrial function, and then affecting the function of nerve cells, resulting in symptoms of autism.
Obviously this is a very general theory. Apart from autism, it can be used to explain any neurological disease, from schizophrenia to Parkinson's disease to Alzheimer's disease.
According to this general theory, antioxidants, such as acetylcysteine, can help cells scavenge free radicals, which may protect or even restore the function of nerve cells and produce therapeutic effects.
But in clinical research, no one checks whether the patient's brain cells really have mitochondrial defects and whether there are too many free radicals-you can't. You can't do a brain biopsy, can you?
The theoretical basis has been general, and clinical experiments are even more general. This is general talk, it's nonsense. Show the grandson that the standard confidant doesn't know that he didn't run away.
This study by George Washington University not only realized this general theory; And it is proved that acetylcysteine is effective-at least for the mouse model with 22q 1 1.2 deletion gene.
The deletion of 22q 1 1.2 refers to the region of1.2 on the long arm of chromosome 22, which contains about 40 genes and is lost for some reason. People with this genetic defect are likely to suffer from neuropsychiatric diseases (about half of the carriers can show symptoms of autism, and about 2% of schizophrenics carry this defect).
The key finding of this study is that compared with normal mice, the bifurcation of brain neurons in mice with 22q 1 1.2 deletion is significantly reduced.
Left: normal mouse neuron right: 22q 1 1.2 mouse neuron deletion.
Think about it, if one day Twist hurts enough to limit everyone's WeChat friends to two or three people, can we still live? ?
The potential reason is that there is an important TXNRD2 gene on this missing chromosome. The protein product of this gene plays a key role in scavenging free radicals produced by mitochondria.
Without such an important role, the free radicals in mitochondria are abused everywhere, making it difficult to work normally and provide enough energy for neurons. Neurons, on the other hand, are not so energetic and make friends everywhere.
Left: Normal mouse neuron mitochondria, the one that looks like peanuts?
Right: 22q 1 1.2 is missing the mitochondria of mouse neurons, which is swollen a lot.
In order to further verify, after the gene was removed in normal mice alone, a large number of free radicals accumulated in brain neurons of mice, and the bifurcation decreased as expected. If the remaining dozens of genes are removed, there will be no such effect.
Therefore, the theoretical basis of mitochondrial defects on which acetylcysteine depends is a real hammer in this special mouse.
Now that we have made clear some theoretical basis, it is obviously logical to do another therapeutic experiment.
Sure enough, if acetylcysteine is added to the drinking water of the mother mouse from the birth of the mouse, and acetylcysteine is also added to the drinking water after the mouse starts to drink water by itself, not only the neurons change, but also the abnormal behaviors such as cognitive ability are obviously improved.
Therefore, if someone intends to do another clinical study of acetylcysteine in the treatment of autism, he can not only more convincingly attack the official who holds the funds, but also have an advanced weapon to improve the success rate of the experiment: do a simple genetic test and pick out those patients who have the gene defect of 22q 1 1.2. In this case, it should be called knowing yourself and yourself.
The reason why the last part of the sentence is not mentioned is that in this study, mice ingest acetylcysteine from birth, which is a critical period for brain growth and development. Patients who participate in clinical research obviously can't meet this condition, so they can't talk more.
But with the present work, I believe that the follow-up research, such as feeding acetylcysteine to model mice of different ages to see the after-effects and using better free radical scavenging methods, is within reach. We are still far from "winning every battle", and I am afraid it is not far away.
References:
Mitochondrial dysfunction leads to insufficient cortical connection and cognitive impairment. Neuron. ? 20 19 Jun 19； 102(6): 1 127- 1 142 . E3。