Researchers discovered that oxytocin, a hormone known for its role in love, lust and labor, may protect brain cells against the ravages of Alzheimer’s.
Oxytocin is involved in female reproduction, released in large amounts during child labor and breastfeeding. It has also earned its reputation as the love hormone, facilitating romantic attachment, but much less is known about its potential role in the neurodegenerative process of Alzheimer’s and related dementias.
Now, new findings published in Biochemical and Biophysical Research Communications suggest that the hormone can reverse some of the harmful effects linked to beta-amyloid, a hallmark protein in Alzheimer’s.
“Our study puts forth the interesting possibility that oxytocin could be a novel therapeutic modality for the treatment of memory loss associated with cognitive disorders such as Alzheimer’s disease,” an author of the study and a professor of pharmaceutical sciences at Tokyo University of Science, Akiyoshi Saitoh, said in a news release. “We expect that our findings will open up a new pathway to the creation of new drugs for the treatment of dementia caused by Alzheimer’s disease.”
Saitoh and colleagues focused on oxytocin’s impact on neurons’ capability of altering the connections in their networks. This ability, known as synaptic plasticity, involves neurons sending electrical signals between one another which change the strength of certain connections.
Synaptic plasticity is critical for people to learn and adapt to their environments. It is also widely thought to enable memories to be stored in the central nervous system.
To confirm that beta-amyloid impairs synaptic plasticity, the team treated samples of male mice hippocampus — a region of the brain critical for memory and learning — with the toxic protein. Subsequently, the signaling abilities of the neurons declined.
When the scientists infused oxytocin in the brain samples containing beta-amyloid, the signaling between the neurons increased, an indication that the hormone was healing the damaged synaptic plasticity of the neurons.
While past research shows that oxytocin is involved in regulating learning and memory performance, Saitoh said this is the first study to show that oxytocin may reverse the impairments linked to beta-amyloid in the mouse hippocampus.
“This is an interesting finding, though the evidence is not yet strong enough to suggest that oxytocin can prevent or reverse cognitive issues from Alzheimer’s,” Eleftheria Kodosaki, an academic associate in biomedical sciences at Cardiff Metropolitan University, wrote in an article for The Conversation.
Among various reasons, Kodosaki said that oxytocin affects males and females differently, and the study only focused on male mice. She added that animals and humans have different physiology and responses to Alzheimer’s.
Further, results from mice studies do not always translate to humans.
Saitoh noted that future research in living animals and humans needs to be conducted before oxytocin can be developed into a drug for Alzheimer’s.
Meanwhile, scientists are making headway in testing oxytocin as a treatment for the behavioral symptoms of people with frontotemporal dementia, a group of disorders which can lead to changes in personality and behavior. In a clinical trial, researchers are examining whether an oxytocin nasal spray can change participants’ apathetic behaviors.