Healing Exercise. From childhood to old age, it is undeniable that exercise is a vital part of a healthy life. Lance Armstrong, who nearly died of cancer but recovered to win the Tour de France five times, is probably the most dramatic example of the benefits of exercise and training. Studies increasingly show that even moderate exercise can be a powerful force for healing cancer’s physical and emotional damage.

Frank Perna, a MED associate professor of psychiatry and graduate medical sciences, leads a team of researchers examining the effects of exercise on the physical and mental health of women being treated for breast cancer. The researchers recruited a multiethnic group of generally sedentary and out-of-shape women with early-stage breast cancer. Half of the women were assigned to a control group and given information regarding healthy lifestyle management, but no formal exercise plan. The other half participated in a four-week exercise program that included monitored aerobic walking and weight training in the hospital, followed by a home-based phase monitored by phone and mail check-ins. This group also was counseled to give them tools to address barriers to exercise and create social supports for their exercise regimens.

Although the study is still in progress, preliminary results, three months after the program began, indicate that the women in the structured exercise group made and kept improvements in cardiorespiratory fitness, strength, and body composition. The exercisers maintained or increased the amount of time they spent exercising over time, and improved on measures of psychological outlook and mood as well. The women in the control group, on the other hand, showed little change, and in some cases declined on measures of physical and emotional health.

Data from follow-ups at 6 and 12 months are now being analyzed, and will provide information on the longer-term effects of supported exercise programs for women with breast cancer.

The study is funded by the National Cancer Institute.

Lighting up the nervous system. Unlike with bones or organs, for which static images can provide useful information for diagnostic and research purposes, understanding the nervous system requires dynamic visualization techniques that can record neurons in action. Functional magnetic resonance imaging (fMRI) can reveal what areas of the brain are working, but a more sensitive technique is needed to see individual neurons in operation. Another approach, using fluorescent dyes, can provide useful information, but applying the dyes is invasive and the dyes themselves last only for a limited period before being cleared from the cells by normal biological processes.

A team of scientists led by Matt Wachowiak, a CAS assistant professor of biology, and Peter Mombaerts at Rockefeller University has taken a major step toward developing a new technology using genetically encoded probes to observe neurons at work in an intact nervous system.

The researchers replaced a protein that normally occurs in the olfactory neurons that line the nasal cavities of mice with a green fluorescent protein sensitive to changes in acidity (pH). The protein is taken up by acidic presynaptic vesicles, areas of the neuron that become less acidic when an odor is detected and the neuron is activated. In the altered cells, this sets off the fluorescent reaction, with different levels of cell activation producing different levels of fluorescent response. By monitoring the levels of fluorescent activity in the cells, the researchers were able to observe how the neurons were responding to external stimuli (odors). They were able to visualize this activity in the brains of intact, living mice.

Wachowiak and his colleagues were able to verify that the response of the altered cells corresponded well with previous results obtained with conventional dyes under the same conditions. However, because their genetic approach creates a permanent change in the DNA of the altered cells, observations can continue over a much longer period, making it possible to observe changes in the nervous system as animals age, learn, or are exposed to different conditions over time.

According to the researchers, “further improvements in genetic probes, gene targeting, and optical imaging technologies promise to greatly expand our window into brain function.”

Their research was published in the April 8, 2004, issue of the journal Neuron.