Scientists had long thought that Alzheimer’s disease and its worst form, dementia, are a condition that affects humans exclusively. In August this year, a Kent State University team found that chimps in research centers and zoos can develop the condition.
With the dolphin discovery, it is the first time the age-related condition is spotted in wild animals. The latest findings, which appeared in the journal Alzheimer’s & Dementia, are further proof that the disease is not human-specific.
Just like humans, dolphins tend to live well past their reproductive period. This tiny detail prompted a researcher to wonder if old age could make dolphins prone to Alzheimer’s disease. The question marked the beginning of new research. In their study, researchers analyzed the brain tissue of dolphins that died on the shores of the Spanish coast.
Dolphins Diagnosed with Alzheimer’s
Laboratory tests revealed plaques of the beta amyloid protein in the dead animals’ brains along with tau protein aka tangles. The two markers herald the onset of Alzheimer’s disease in people.
In healthy people, beta amyloids vanish while in people prone to Alzheimer’s the proteins accumulate, forming plaques between nerve cells. The plaques prompt the formation of tau cells which further damage the brain. These two factors lead to dementia over time.
Study authors couldn’t tell why dolphins developed the condition or whether the disease was associated with confusion and memory loss as it usually is in humans. They said they need to study live dolphins to provide an answer to those questions.
Researchers suspect that the main culprit in the onset of the disease is a faulty insulin function. Insulin changes known as insulin signaling can lead to diabetes in humans and animals alike. When paired with caloric restrictions, insulin signaling can extend the lifespan of humans and animals well beyond their fertile years. But there is a price to pay: type 2 diabetes and Alzheimer’s disease.
Image Source: Pixabay