New research suggests symptoms of early-onset dementia in five adults may be related to now-discontinued human growth hormone treatment they received decades ago as children. It suggests that.
The study, published Monday in Nature Medicine, provides the first reported evidence of medically acquired Alzheimer’s disease in a living human. In these cases, the patient’s early-onset dementia symptoms may be due to possible infection with amyloid beta protein, a key component of Alzheimer’s disease that forms plaques in the brain.
Abnormal accumulation of the protein amyloid beta in the brain is associated with Alzheimer’s disease, and new research suggests amyloid beta contamination may be linked to early dementia symptoms experienced by patients studied It suggests. The study results do not suggest that Alzheimer’s disease can be contagious or widespread, for example, like viral or bacterial infections, but they do raise new questions about Alzheimer’s disease and other degenerative diseases. .
“We want to emphasize that these events are extremely rare events, and the majority are associated with medical practices that are no longer in use,” said lead author of the study, University John Collinge, Director of the College London Prion Disease Research Institute, said: he said at a press conference.
All five adults suffered from growth hormone deficiency as children and were given pituitary growth hormone specially produced from cadavers. The pituitary gland is located at the base of the brain, and human growth hormone (HGH) is a natural hormone produced and released by the pituitary gland that promotes growth in children.
According to the study, these patients were among at least 1,848 people treated with human growth hormone extracted from cadaveric pituitary glands in the UK between 1959 and 1985. At the time, this treatment was also used in other parts of the world, including the United States. The treatment was abandoned after cases of a rare brain disease called Creutzfeldt-Jakob disease were linked to the administration of contaminated human growth hormone taken from cadavers.
A new study shows that repeated exposure over several years to therapeutic drugs containing HGH taken from cadavers contaminated with both prions and amyloid beta seeds associated with Creutzfeldt-Jakob disease can spread Alzheimer’s disease. It suggests something. Prions are proteins that can act as infectious agents of neurodegenerative diseases.
Researchers believe that under certain circumstances, Alzheimer’s disease can be linked to “prion diseases,” a family of rare progressive neurodegenerative diseases known to be associated with Creutzfeldt-Jakob-related prion proteins. It could be transmitted in a manner similar to that of a disease known as , the researchers wrote in the study. disease or CJD. Although Alzheimer’s disease is not a prion disease, other research suggests that two proteins characteristic of Alzheimer’s disease, amyloid beta and tau, behave like prions.
“What’s happening in Alzheimer’s disease appears to be very similar in many ways to what’s happening in human prion diseases like CJD,” Collinge said at a press conference. “That has implications for treatments for Alzheimer’s disease.”
‘The public has nothing to fear’
In 2015, researchers previously found ‘possible evidence’ that amyloid-beta protein, found in growth hormone, can be transferred from cadavers to recipients. reported and investigated this in laboratory mice in 2018.
“We now provide evidence that Alzheimer’s disease is also contagious under certain circumstances,” researchers from University College London and the UK’s National Hospital for Neurology and Neurosurgery said in the study. ing. However, it added that this type of infection is “rare” and there is no evidence that amyloid beta can be transmitted in humans in daily activities or in modern routine medical care.
“After the use of human growth hormone was discontinued in the 1980s due to concerns about the transmission of Creutzfeldt-Jakob disease, strict procedures were put in place to minimize cross-contamination.”However, these In light of their findings, the researchers recommend that medical procedures be reviewed to prevent such rare cases of Alzheimer’s infection from occurring in the future. Susan Koolhaas, Alzheimer Research UK’s executive director of research and partnerships, spoke about the new research in a written statement distributed by the UK’s Science Media Centre.
“This study suggests that Alzheimer’s disease can be transmitted in humans through human growth hormone from deceased donors, although in very rare cases. It is important to emphasize that this treatment is no longer in use and has been replaced by synthetic growth hormone,” Dr. Koolhaas said in a statement. “It is also important to emphasize that this is the only documented case of Alzheimer’s disease being transmitted between humans.”
Dr. Richard Isaacson, who was not involved in the new study, said in an email that he has long suspected that Alzheimer’s disease is as contagious as prion disease, but that he has He said the research he saw may not prove that.
“It’s hard to say, but there must be something different about how HGH was transmitted to recipients in this study compared to previous studies,” says the Florida Institute for Neurodegenerative Diseases. said Isaacson, head of research.
This type of human growth hormone treatment is no longer used in clinical practice, so “the public has nothing to fear,” he added, but the study will focus on sterilization and decontamination of instruments between surgeries. importance is emphasized.
Although there is no evidence that amyloid beta can be transmitted between individuals during daily activities, “this recognition requires a review of measures to prevent accidental infection from other medical and surgical procedures.” ,” the researchers wrote in their study.
“We’re also excited to see how these results will inform future therapeutic targets and strategies,” Isaacson said, referring to Alzheimer’s disease.
‘Ask new scientific questions’
Researchers looked at eight cases previously treated with human growth hormone obtained from cadaveric pituitary glands. Everyone was treated like a child. Five of the patients were still alive during the study period and were in their 50s. The other three people died at ages 57, 54 and 47. The researchers found that five of the patients had symptoms consistent with early-onset dementia, and three of them had been diagnosed with Alzheimer’s disease before the study. Four of the patients developed symptoms between the ages of 48 and 49. In the remaining patients, symptoms appeared at age 55 years.
“We now know that amyloid-beta pathology is contagious and may contribute to the development of Alzheimer’s disease,” he said. Gargi Banerjee, lead author of the study and a researcher at the Institute of Prion Diseases at University College London, said in a press release.
“This infection occurred after treatment with the now-obsolete growth hormone and repeated treatments with contaminated material, often over several years,” Banerjee said. “There is no evidence that Alzheimer’s disease can be transmitted through close contact or routine care.”
This new study is the first conducted by Drs. James Galvin, director of his UHealth Center for Brain Health at the University of Miami Health System, hears about the transmission of Alzheimer’s disease to humans.
“All incidents are very recent, raising the suspicion that external factors may be involved. Early onset is usually associated with genetic mutations, but this was not found, making it the most common “The cause may be growth hormone treatment of the cadavers. Further investigation is needed,” Galvin, who was not involved in the study, said in an email.
“At this point, we can say that nothing more needs to be done in terms of clinical practice, but this certainly helps in asking new scientific questions.” Creutzfeldt-Jakob disease and bovine spongiform encephalopathy are contagious “It could be,” he said. “Additionally, other proteins thought to be involved in the disease, such as alpha-synuclein in Parkinson’s disease and Lewy body dementia, share some of these properties, but do not appear to be transmissible. ” In Alzheimer’s disease, we may need to understand the science of amyloid and tau proteins. I reconsidered. ”
