Fat facts: The identification of a protein that helps the body overcome leptin resistance could lead to the development of drug therapies for obesity, say researchers at Beth Israel Deaconess Medical Center in Boston.

        Most obese people are resistant to the effects of leptin, a hormone that signals the brain that the appetite is satisfied and it's time to stop eating. For that reason, obesity treatments that rely on leptin have been unsuccessful.

        “The majority of obese people actually have high levels of leptin, but they are unable to put it to use,” says Dr. Barbara Khan, chief of endocrinology and metabolism at the hospital and senior co-author of the study.

        The finding actually grew out of research to identify the role of the molecule protein-tyrosine phosphatases 1B (PTP1B) in regulating insulin receptor signaling.

        Researchers designed a group of lab mice without the protein, and, as they had guessed, the mice were hypersensitive to insulin. But they were also surprisingly lean and gained much less weight than normal mice when fed a high-fat diet.

        Further testing showed that the modified mice were expending high levels of energy, and researchers surmised that the PTP1B was controlling the leptin signal pathway that regulates appetite.

        The finding gives scientists a molecular approach to overcoming leptin resistance and provides a target for drug development to treat obesity and diabetes, says Dr. Benjamin Neel, co-author of the study and director of the Cancer Biology Program at Beth Israel Deaconess.

        The study was published in the April 16 issue of Developmental Cell.

Tips

        Stay motivated: If you've lapsed on your New Year's fitness resolutions, May is National Physical Fitness and Sports Month, and the experts at the American Council on Exercise say it's the perfect time to get back to that workout.

        Their tips:

        • Be specific: Make a plan of action to walk for 30 minutes every Tuesday and Thursday, for example, instead of vaguely resolving to exercise more.

        • Find a partner: If your buddy's already committed to an exercise routine, he or she will be happy to help you get hooked.

        • Be realistic: Make your new routine as easy and convenient as possible. If you're exhausted when you get home from work, you're not likely to make it to an evening aerobics class.

        • Lose the scale: Focus on meeting your exercise goals and following a healthy, low-fat diet, not on losing pounds and inches.

        For more ideas, check out the council's Web site, www.acefitness.org.

Calendar

        Benefit: The American Cancer Society is recruiting participants for its Relay for Life, an 18-hour overnight benefit relay run/walk to battle cancer. Relays have been scheduled at several locations throughout Greater Cincinnati in May and June. For specific dates and locations and registration information, call 891-1600. Siting

        Fore: Check out www.golf101.com for tips and information on improving your golf game. The site will help bring out your inner Tiger Woods with information on the basics, sand traps and water hazards, course reviews, fitness tips and instructional books and videos.