Breaking down barriers usually sounds like a good thing, but not for aging stem cells.
When young brain stem cells split in two, they can wall off damaged proteins in one daughter cell, leaving the other spry and ready to divide again, researchers report in the Sept. 18 Science. With age, the barrier sequestering the damaged proteins breaks down, spilling cellular garbage into both cells, the team also discovered. The spillover may diminish older stem cells’ ability to divide and replenish tissues. Learning why such barriers fall apart may eventually lead to new kinds of antiaging therapies.