Childbirth, the key to understanding autism

2019/01/30 Agirre Ruiz de Arkaute, Aitziber - Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Medikuntza
• Farmakologia
• Berdintasuna

According to a study published in the journal Science Advances, the timing of childbirth can be key to the development of autism. At the moment, they have been tested in animals, but the results have shown that no decrease in brain activity during childbirth can have consequences on the subsequent neurological development of the brain.

Birth is a critical moment for mammals. It is so critical that the child's brain should be expressly prepared for childbirth. Oxytocin reduces the activity of neurons, making the child's brain less active at that time of stress. It is somehow a way to protect the brain. “prepares him for that traumatic moment, so that he may suffer less. When it is not so active, the brain is less sensitive,” explains Paolo Bonifazi, one of the researchers and authors of the study.

Oxytocin is a key hormone in all of this: it starts childbirth, strengthens the emotional bond between mother and child and helps prevent the adverse effects of stress during childbirth. “The oxytocin produced by your mother sends the signal to the baby’s neurons so that, before delivery, they open an inhibitory signal between them,” explains Bonifazi. In some cases, oxytocin does not emit this inhibitory signal to the brain. Not protecting the brain at that time can cause damage. They say that there is the key to understanding autism, according to Bonifazi. “Somehow, neurons stay as if they are permanently excited, as if they are immature, and can cause neurological problems in the future.”

At the moment, these results have been seen in experiments with rats, led by neurobiologist Yehezkel Ben-Ari, in Marseille. The laboratory has compared the births of two groups: normal rats and rats in which balproic acid has been injected into the uterus. In fact, balproic acid causes autism if taken during pregnancy. Bonifazi has studied the morphology of neurons before and after childbirth and has observed that in normal neonatal rats the brain does not grow in the two days near childbirth, while in newborn autistic rats the brain has continued to grow and the neurons of the hippocampus continue to spread.

Epidemiological studies have previously suggested that autism may be related to birth related disorders, such as cesarean sections, premature births, and problems at the time of delivery. This study confirms that birth is a critical moment and may have to do with the pathogenesis of brain diseases.

In the second phase of the research it has also been sought to test the efficacy of a drug that has given bumetamide to rats autised before delivery, since this drug also produces inhibitory signals, as well as oxytocin. After administration, researchers have found that brain development is stopped before delivery. “As with animals, we believe it brings benefits to autistic children. Medicine changes the way the neuron works and the brain works better. Clinical trials are now being developed because we believe it can contribute to the development of these neurons that have been permanently excited,” explains Bonifazi. “It doesn’t cure the disease, but it can reduce symptoms for better social integration.”

According to researchers, birth is the most complex biological mechanism that occurs in mammals and it is essential to investigate more. Great hormonal, physiological, immunological, microbiotal and vascular changes occur, but it is surprising to know little about them in view of their consequences.

More information about oxytocin: Oxytocin: Hope Hormone