If you’re among the millions of aging baby boomers who cringe every time they see the cashier ring up a box of Depends, take heart: That problem may soon be a thing of the past. Scientists from the United States and Australia say the urinary incontinence that often accompanies age or injury can be surgically cured—in animals, at least.
Searching for a way to help people regain control over their unreliable bladders, Anthony Atala, a urologist at Children’s Hospital Boston, injected stem cells from the limb muscles of rats into their deliberately damaged urinary sphincters, which control flow. The stem cells developed into new muscle fibers, and within one month, the sphincter function improved by 40 percent. “Not only were we seeing the formation of new muscle tissue but also the reenervation and interconnection of nerve endings, which enabled the rats to regain control over their muscle function,” Atala says. An equivalent operation for humans will not be available for at least a few years: “It’s a matter of making sure we can go up the ladder in terms of more complex defects,” he says.
Meanwhile, John Furness, a cell biologist at the University of Melbourne in Australia, thinks bladder control could someday be as simple as pushing buttons on a remote control. Furness’s surgical technique, tested successfully in rats, rabbits, and dogs, involves removing muscle tissue from various parts of the body to create a replacement urinary sphincter, then implanting the sphincter along with a small electrical stimulator similar to a pacemaker. If a human recipient needed to urinate, he or she would click a control button, signaling the stimulator to relax the sphincter, then click again to stop the flow. Furness plans clinical trials next year.
