As the spotlight-seeking keener he portrayed as Alex P. Keaton on the 1980s sitcom Family Ties, Michael J. Fox seared his boyish good looks and infectious energy into the minds and hearts of millions. Today, the 57-year-old is parlaying his enduring popularity into an even greater role – mobilizing patients and researchers to bring an end to Parkinson’s disease, which affects one in 100 people over age 60.