If a person takes oxytocin, also known as the ’love hormone’, in the form of a nasal spray for a sustained period, the body will start to produce more oxytocin by itself. This was the effect found by researchers at KU Leuven in people with autism. One month after treatment, they still showed elevated oxytocin levels in their saliva. The results were published in the journal European Neuropsychopharmacology.
In an earlier study , Professor Kaat Alaerts and her colleagues had found that administration of oxytocin has an influence on the behaviour of people with autism. Now, they identified the evidence for this change in behaviour: their oxytocin levels were elevated. "We started looking at the effects of what is known as the ’love hormone’ in 40 adult men with autism spectrum disorder," explains Professor Alaerts.
"At the start of the study, we took a sample of saliva from each of them to determine their individual oxytocin level, to provide a baseline measurement. The test group was then given oxytocin every day for a month in the form of a nasal spray, while the control group received a placebo." Another saliva sample was collected twenty-four hours after the last dose, and again four weeks later.
Oxytocin makes us behave more socially. In turn, social contact causes the body to produce extra oxytocin, which may then promote more social behaviour, and so on.
Analysis of these saliva samples now shows that participants who were given oxytocin for four weeks still had higher levels of the hormone in their bodies up to a month after treatment. "This cannot possibly be residue from the externally administered doses and we concluded that it was produced by their own bodies," says Professor Alaerts. She also identifies an immediate explanation: "Oxytocin makes us behave more socially. In turn, social contact causes the body to produce extra oxytocin, which may then promote more social behaviour, and so on."
"The results we present today are the outcome of an initial pilot study. A great deal more research is required before oxytocin can be used to treat social difficulties or attachment problems," notes Professor Alaerts.
Follow-up study already under way
The first follow-up study is already under way. Professor Alaerts’ team is currently working on a study of the effects of oxytocin in children with autism spectrum disorder between the ages of 8 and 12. There are also plans for a similar study on a larger scale to demonstrate the effects of the love hormone in even more target groups, such as in children with mental disabilities in addition to autism.
This research was conducted in collaboration with Professor Jean Steyaert, head of the Leuven Autism Research Consortium (LAuRes) and was made possible thanks to funding from the Branco Weiss Fellowship (ETH Zurich), the Marguerite-Marie Delacroix Foundation, and the Research Foundation Flanders.
The study " Changes in endogenous oxytocin levels after intranasal oxytocin treatment in adult men with autism: An exploratory study with long-term follow-up " by Kaat Alaerts, Jean Steyaert, Bart Vanaudenaerde, Nicole Wenderoth and Sylvie Bernaerts was published in European Neurophysopharmacology.