Energy Production Deficit Affects Brain.

• Position: AGE-RELATED DISEASES

Defective energy production in old neurons might explain why our brains are so prone to age-related diseases. Researchers from the Salk Institute for Biological Studies, La Jolla, Calif., used a new method to discover that cells from older individuals had impaired mitochondria--the power stations of cells--and reduced energy production.

A better understanding of the effects of aging on mitochondria could reveal more about the link between mitochondrial dysfunction and age-related brain diseases, such as Alzheimer's and Parkinson's.

"Most other methods use chemical stresses on cells to simulate aging," says senior author Rusty Gage, professor in the Laboratory of Genetics. "Our system has the advantage of showing what happens to mitochondria that age naturally within the human body."

Mitochondria, small structures found within cells, are responsible for converting our food into chemical energy our cells can use. Defects in mitochondrial genes can cause disease, but researchers also know that mitochondria become less efficient with aging and can drive age-related disorders.

Previously, the Gage lab developed a method to convert skin cells into neurons--called induced neurons, or iNs--directly. Most methods to create neurons from patient cells rely on an intermediary stem cell step (creating what are called induced pluripotent stem cells), which resets cellular markers of aging. However, the Gage...