TL;DR
Most Alzheimer's drugs try to fight the disease inside the brain. A new rat study points at a different organ: the liver. As animals age, the tiny pores in the liver's lining, which act as a filter, close up. Researchers at USC's Keck School of Medicine gave aged rats two weeks of an experimental drug called cinaciguat, and the pores came back. Amyloid beta in the blood, the sticky protein behind Alzheimer's plaques, fell by half to match young rats, and LDL cholesterol dropped to young-rat levels too, a result the team did not expect. It is rat work, and nobody has yet tested whether lowering amyloid this way prevents Alzheimer's, but it adds an organ that could be repaired from outside the brain to the list of ways to keep minds young. To see our odds on when a liver-pore drug reaches people, and the timeline of breakthroughs that leads there, subscribe.
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