Can Alzheimer's disease be passed on to others?

Pathological beta-amyloid protein transferability confirmed

Alzheimer's disease is a dreaded neurodegenerative disease that primarily affects the elderly and has increased dramatically in recent decades. By 2015, researchers at Univesity College London had suggested that the disease could be transmitted via misfolded amyloid proteins. In laboratory experiments on mice, they have now confirmed the suspicion.

Alzheimer's disease is considered a noncommunicable disease. It threatens no infection in ordinary contact with stakeholders, say British scientists. However, a 2015 study has already shown that pathological amyloid beta proteins could be transmitted from man to man as part of a medical treatment. In their current study, researchers at University College London have confirmed it. Their results were published in the journal "Nature".

Transmission in hormone therapy?

"Our previous study found that some people who developed CJD many years after treatment with pituitary growth hormone also had deposits in the brain of an abnormal protein characteristic of the disease. Alzheimer's, "says the main author. the study, Professor John Collinge from the starting point of the ongoing investigation. Reason has suspected researchers in the transmission of misfolded protein structures with growth hormones. In their current research, they have now shown that pituitary growth hormone actually contains the corresponding beta-amyloid proteins.

Contamination by growth hormone

"The results support the hypothesis that amyloid-beta would have been inadvertently transmitted to patients through this long-discontinued medical treatment," the researchers said in a press release. The human growth hormone – made from human tissue before 1985 – actually contained amyloid beta-amyloid deposits of Alzheimer's disease. During the next step, the research team examined whether protein contaminants in the growth hormone also resulted in the development of amyloid deposits typical of Alzheimer's disease.

Experiments on mice

The researchers injected transgenic mice containing the contaminated growth hormone into the brain and found that after less than 12 months, a "clear seeding of amyloid pathology in their brains" had already taken place. The same was observed in mice injected with tissue from patients with typical Alzheimer's disease. However, mice given synthetic growth hormone or normal brain tissue did not exhibit such trends.

Beta amyloid pathology is transferable

"We have now presented experimental evidence to support our hypothesis that the pathology of beta amyloid can be transferred from contaminated materials to humans," said Professor Collinge. However, it is not yet clear whether Alzheimer's disease can be caused or transmitted to humans through medical or surgical interventions. "It will be important to review the risks of transmitting amyloid pathology in other medical procedures still used nowadays, including brain surgery tools," said the expert.

Threat of an infection in contact with patients with Alzheimer's disease

The present study provides new information on the molecular mechanisms underlying the role of amyloid in Alzheimer's disease, but the researchers explicitly pointed out that there was currently no evidence of Alzheimer's disease between humans. The study gives no indication that you can contract Alzheimer's disease through contact with a sick person. (Fp)