Stem cells are the fountain of youth or the tools of Satan. It depends who you ask. Somewhere in between are pioneering companies making strides in medicine. And while it may be decades before an injection will repair a damaged spine, over the next few years stem cells will speed drug development, eliminate unsafe meds and create better diagnostic tests, Forbes writes in a special report.

For instance, neuroscientist Carrolee Barlow quit a research job at Merck because she thinks everything you’ve heard about antidepressants is wrong. The idea that Prozac, Zoloft and their ilk work by fixing an imbalance in the chemical serotonin is so mainstream that drugmakers use it in their ads, the mag writes.

But in 2003 Columbia University neuroscientist René Hen showed that the drugs’ most important function may be to spur the growth of new neurons in the brain. Block the growth of new brain cells in mice, and Prozac and other antidepressants don’t work, he discovered.

Barlow is now chief scientific officer of BrainCells, a fledgling San Diego firm founded on this work and backed with $77 million in funding from AstraZeneca and other investors, Forbes writes. And Barlow hopes to create antidepressants designed specifically to spur brain cell growth, with the thought that they’ll be more effective and safer than existing drugs.

The company mixes experimental drugs with neural stem cells in the test tube, searching for the rare chemicals that make the stem cells form neurons faster. The firm already has one neuron-boosting drug in trial for depression, with two others close behind. “This opens up whole new possibilities for mood disorders,” Barlow tells Forbes.

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