August 1, 2019
A new study by LRA Distinguished Innovator Award recipient Dr. Douglas Green of St. Jude Children’s Research Hospital in Memphis, TN, and colleagues may have uncovered a new way to treat Alzheimer’s disease. The research, highlighted recently in Forbes magazine and published in the journal Cell, identified one of the brain’s mechanisms for destroying a molecule that may be a culprit in the disease.
“This study illustrates the synergies we foster across diseases,” commented Teodora Staeva, PhD, Chief Scientific Officer of the Lupus Research Alliance. “The body is not a collection of isolated parts, and understanding what goes wrong in one area can help understand what goes wrong in others. Learning from discoveries in different disciplines can greatly advance our understanding of lupus and vice versa.”
The scientists were studying a type of recycling in the body known as autophagy, in which cells partially recycle themselves. During autophagy, which means “self-eating,” cells digest some of the material inside themselves. Cells use autophagy when they are hungry, but it also helps them clean up, eliminating damaged molecules or internal structures that can be harmful. This type of cellular recycling may not work properly in patients with lupus.
Dr. Green and his team found that some proteins necessary for autophagy also play another role. They enable certain immune cells in the brain to break down a molecule known as β-amyloid that may trigger Alzheimer’s disease. Clumps of β-amyloid form in the brains of patients with the disease, and they may cause harmful inflammation and lead to the death of brain cells. The researchers found that mouse models that did not have the autophagy proteins built up more of these distinctive clumps. Brain cells died faster in the mouse models, and the animals also developed some symptoms of Alzheimer’s disease, including memory problems.
The brain makes less of the autophagy proteins as we age, which may help explain why Alzheimer’s disease is more common in older people. The study suggests that developing new drugs that stimulate the immune cells to destroy β-amyloid could help treat the disease.
“Our research into the role of autophagy proteins in lupus has unexpectedly led us into a new understanding of Alzheimer’s Disease,” said Dr. Green.