Exercise, calorie restricted diet 'lowers postmenopausal women's breast cancer risk'

Good morning friends. After reading news I want to share it to everyone specially to women out there. It's important.

Regular exercise and reduced-calorie diet can significantly cut breast cancer risk in postmenopausal women, suggests a new study.

The research team from University of Texas at Austin have identified pathways by which calorie restriction and exercise can modify a postmenopausal woman's risk of breast cancer. They found that both caloric restriction and exercise affect pathways leading to mTOR, a molecule involved in integrating energy balance with cell growth. Dysregulation of the mTOR pathway is a contributing factor to various human diseases, including cancers.

Diet and exercise reach mTOR through different means, with calorie restriction affecting more upstream pathways, which could explain why caloric restriction is more efficient in delaying tumour growth than exercise in animal models. "One of the few breast cancer modifiable risk factors is obesity," said lead author Leticia M. Nogueira, Ph.D., a research graduate assistant at the University of Texas.

"Our study may provide a good scientific basis for medical recommendations. If you're obese, and at high risk for breast cancer, diet and exercise could help prevent tumour growth," she added.
The research suggests that inducing a so-called "negative energy balance" (where less energy is taken in than expended) through eating a low-calorie diet or increasing exercise levels, decreases the postmenopausal breast cancer risk associated with obesity. Increased levels of leptin and decreased levels of adiponectin have been associated with breast cancer risk.

For eight weeks, they administered a high-fat diet to 45 mice that had their ovaries surgically removed to model the post-menopausal state.

During week nine of the study, the diet-induced obese mice were randomly assigned to one of three groups: a control group, permitted to eat at will; a group fed a diet reduced in calories by 30 percent; and a group that was permitted to eat at will but exercised on a treadmill for 45 minutes a day, five days a week. At week 16, researchers collected tissue from the mice for analysis.
The study showed that blood levels of leptin, a hormone that plays a role in fat metabolism, were significantly reduced in the calorie-restricted mice while blood levels of adiponectin showed an increase.

She also found that the key proteins found downstream of mTOR activation were less active in both the calorie-restricted and exercised mice compared to the controls. "These data suggest that although exercise can act on similar pathways as caloric restriction, caloric restriction possesses a more global effect on cell signaling and, therefore, may produce a more potent anti-cancer effect," Nogueira said.

The study was presented at the American Association for Cancer Research's Seventh Annual International Conference on Frontiers in Cancer Prevention Research. (ANI)

Listen to joyful music to stay healthy

For the first time, researchers at the University of Maryland School of Medicine in Baltimore have shown that the emotions aroused by joyful music have a healthy effect on blood vessel function.

Music, selected by study participants because it made them feel good and brought them a sense of joy, caused tissue in the inner lining of blood vessels to dilate (or expand) in order to increase blood flow, the study found.

On the other hand, when study volunteers listened to music they perceived as stressful, their blood vessels narrowed, producing a potentially unhealthy response that reduces blood flow. The results of the study, conducted at the University of Maryland Medical Center, have been presented at the Scientific Sessions of the American Heart Association in New Orleans.

"We had previously demonstrated that positive emotions, such as laughter, were good for vascular health. So, a logical question was whether other emotions, such as those evoked by music, have a similar effect," says principal investigator Michael Miller, M.D., director of preventive cardiology at the University of Maryland Medical Center and associate professor of medicine at the University of Maryland School of Medicine.

"We knew that individual people would react differently to different types of music, so in this study, we enabled participants to select music based upon their likes and dislikes," the expert added. Ten healthy, non-smoking volunteers (70 percent male, average age 36 years) participated in all phases of the randomized study. There were four phases. In one, volunteers listened to music they selected that evoked joy.

The volunteers brought recordings of their favorite music to the laboratory, or, if they did not own the music, the investigators acquired the recordings. Another phase included listening to a type of music that the volunteers said made them feel anxious. In a third session, audiotapes to promote relaxation were played and in a fourth, participants were shown videotapes designed to induce laughter.