A study said that a woman escaped Alzheimer's even though half of her relatives had it, which means she holds clues on how to prevent the disease.
A Colombian family has been plagued by Alzheimer's disease for generations, with half of its members afflicted in their prime. But one member of that family escaped what seemed like an inevitable fate. Despite inheriting the genetic defect that caused her relatives to develop dementia in their 40s, she remained cognitively healthy into her 70s.
Researchers at Washington University School of Medicine in St. Louis now think they know why.
They found she had two copies of a gene called apolipoprotein E, or APOE, known as the Christchurch mutation, which they believe could help prevent Alzheimer's from progressing.
Dr David Holtzman, from Washington University in St Louis, said: “Any protective factor is very interesting, because it gives us new clues about how the disease works. As people get older, many start to develop some amyloid buildup in their brains. At first, they remain "Cognitively normal. However, after many years, amyloid deposition begins to cause tau to accumulate. When this happens, cognitive impairment quickly occurs."
He continued: "If we can find a way to mimic the effects of the APOE Christchurch mutation, we may be able to stop people who are already on the path to developing Alzheimer's from continuing down that path."
Alzheimer's disease is the most common form of the condition, and is thought to be caused by a buildup of proteins in the brain, including tau and amyloid.
Alzheimer's disease develops over about 30 years. The first two decades or so are silent, as amyloid slowly builds up in the brain without causing any harmful effects. When amyloid levels reach a tipping point, they begin the second phase, which involves multiple, interconnected destructive processes. A protein called tau forms tangles that spread across the brain, the brain's metabolism slows, the brain begins to shrink, and people begin to experience problems with memory and thinking. The disease follows the same pattern in people with genetic and non-genetic forms of Alzheimer's disease.
There is currently no cure for this disease, although there are three promising drugs to slow its progression currently in trials.
The study, published in the journal Cell, looked at Colombian families who have a mutation in a gene called presenilin-1, which causes greater amyloid buildup in their 20s.
This usually causes cognitive decline in early middle age, but researchers identified an exception in a woman whose identity has not been revealed.
She had more amyloid in her brain in her 70s than her relatives in their 40s, but she did not show signs of brain injury and cognitive impairment.
“One of the biggest unanswered questions in the field of Alzheimer's disease is why amyloid buildup leads to tau,” Dr. Holtzman said. “This woman was very unusual in that she had amyloid but not a lot of tau and very mild cognitive symptoms.” "Late. This suggests to us that it may hold clues to this link between amyloid and tau."
The researchers looked at mice that had high amounts of amyloid and genetically modified them to carry the same Christchurch mutation that the woman had.
After injecting tau protein into their brains, the team found that the mice did not experience the same spreading of the protein that normally occurs in brains containing large amounts of amyloid.
This means they were less likely to suffer from brain degeneration and cognitive problems.
Dr. Holtzman added: "If we can mimic the effect that the mutation has, we may be able to make amyloid buildup harmless, or at least much less harmful, and protect people from developing cognitive impairment."
A simple exercise helps ward off the risk of breast cancer in women
A study showed that walking can help reduce the risk of breast cancer in women by 10%.
Exercise, such as walking, cycling and other sports, helped reduce the risk of developing the disease before menopause, with the most active women receiving the greatest benefits.
Dr Michael Jones, from the Institute of Cancer Research in London, said: “These findings add to a strong body of evidence showing that physical activity is good for our health. Our research adds to evidence suggesting that engaging in higher levels of leisure-time physical activity may lead to Reducing the risk of breast cancer before menopause.
He continued: "We still need to better understand the biology behind the relationship between physical activity and a reduced risk of breast cancer."
Breast cancer affects both men and women, but it is more common among women. Breast cancer occurs when some breast cells begin to grow abnormally.
Experts are still not sure exactly what causes it, but risk factors include age, family history, height, being overweight or obese, alcohol, and having had the disease before.
Previous research has shown that walking about 6.5 hours a week can reduce risk by up to 30%.
The latest research, published in the Journal of Clinical Oncology, looked at data from 19 studies around the world, including more than 547,000 women.
They were followed for an average of 11.5 years, and 10,231 of them were diagnosed with premenopausal breast cancer.
Women who were among the most active 10% were 10% less likely to develop the disease than those who were least active, after adjusting for body mass index.
Breast cancers in younger women "tend to be more aggressive and are diagnosed at a late stage," explains Dr Simon Vincent, of Breast Cancer Now.
He added: “So, we urgently need to find new ways to prevent people from getting the disease. Although we cannot predict who will develop breast cancer, there are some things people can do to reduce their risk. This research highlights: "How important it is to support women to start making small, healthy lifestyle changes that can positively impact their health."
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