AN ANCIENT CELLULAR PROGRAM to protect cells when oxygen is low seems crucial for the production of new brain cells.

For more than two billion years on this planet, O2 has been the go-to gas for generating efficient cellular energy. But life on Earth never takes oxygen for granted. “When it runs low, cells swiftly adapt,” says cell biologist Celeste Simon.

This ancient adaptive reaction, known as the low-oxygen, or hypoxia, response, typically involves a cascade of protective changes in cells: protein synthesis drops and cells switch to a less efficient process of energy production that doesn’t require oxygen. But organisms have evolved uses for the hypoxia response that are not merely protective.

Simon, an HHMI investigator at the University of Pennsylvania, recently found evidence that the response is crucial for maintaining the health of stem cells in the hippocampus, a key memory region of the brain. The discovery could alter our understanding of a host of stem cell-related brain conditions.

via HHMI Bulletin May 2011: Oxygen on the Brain.