For the first time, symptoms of Alzheimer's disease were found in dolphins living in the wild. Animals can become models for finding the causes of disease in humans.
An international team of researchers has discovered two main hallmarks of Alzheimer's in the brains of wild dolphins: amyloid plaques and neurofibrillary tangles. These are the first known cases of the disease in animals living in the wild. In the future, this finding will make it possible to use animal brains to study the causes of disease in humans.
Dolphins live for a relatively long time, including after the end of their reproductive period. The researchers hypothesized that the brains of animals could undergo changes that are characteristic of old age.
For example, the striped dolphin Stenella coeruleoalba lives on average 55-60 years.
The authors of the work studied the brains of eight dolphins, thrown by the sea on the coast of Spain. The animals belonged to several different species. In the brains of animals, amyloid plaques were found - accumulations of peptides "folded" into flat beta folds. Also, neurofibrillary tangles were found in the brains of dolphins. These structures arise from overphosphorylated tau protein. In a healthy brain, tau protein regulates the function of cellular microtubules, but the overphosphorylated protein becomes insoluble and cannot perform its functions. The same manifestations are associated with Alzheimer's disease in humans.
This research is only the first stage of a long work. It is not known whether the dead wild dolphins suffered from memory impairments and inability to navigate. Further research will show whether such brain changes can lead to cognitive impairment. This can be explored by working with captive dolphins.
The research is published in the journal Alzheimer's & Dementia.
Natalia Pelezneva
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