Scientists are making progress in unraveling the complex biochemistry of oxidative stress: how it originates, how it damages our cells, how it contributes to age-related conditions. Via RxPG News, a look at recent research: "Just as humans undergo daily stress, so do our individual cells. The cellular variety, called oxidative stress, is caused by the build-up of free radicals, which over time inflict damage linked to aging and age related diseases such as Alzheimer's. [Researchers] have now defined a molecular signaling pathway by which oxidative stress triggers cell death, a finding that could pave the way for new drug targets and diagnostic strategies for age-related diseases. ... Once stimulated by oxidative stress, MST acts in its capacity as an enzyme to modify and thereby activate the FOXO proteins, instructing the FOXO proteins to move from the periphery of the cell into the nucleus of neurons. Once in the nucleus, the FOXO proteins were found to turn on genes that commit neurons to programmed death."