USC Trojan Family Magazine - Summer 2002: What's New: Health News

HEALTH NEWS
ABC's of Lung Health

Vitamins play a crucial and lifelong role in children’s pulmonary development, a new Keck School of Medicine study shows.

An apple a day might keep doctors away after all, especially if those physicians are pulmonologists. USC research shows that school kids who eat plenty of fruit and consume fruit drinks containing antioxidants have more developed lungs.

The lungs’ nutritional hero from the antioxidant world seems to be vitamin C, says researcher Frank D. Gilliland of the Keck School of Medicine of USC. Vitamins E and A also play a role in lung function, especially in children with asthma.

Gilliland, an associate professor of preventive medicine, and his colleagues studied some 2,500 children ages 11 to 19 in a dozen Southern California communities. They asked children about their diet and calculated the kids’ vitamin consumption. They also tested lung function by measuring how much air each child could blow out – and how quickly – after taking a deep breath.

Kids who got fewer antioxidants in their diet showed deficits in lung function: They couldn’t blow out as much air or exhale it as fast as kids with higher vitamin consumption.

“This consumption of vitamins seems to come mostly from fruit and juice intake in children,” Gilliland says. “Among the juices, apple and grape juice especially seemed important.”

Lung function normally peaks in the late teens and early 20s. Thereafter, it generally declines by about 1 percent a year over the rest of one’s lifetime (or by 2 percent for smokers).

Scientists believe that deficits in lung growth during the teen years may contribute to breathing problems later in life, such as chronic obstructive pulmonary disease – the fifth leading cause of death in America.

So how do antioxidants help?

“Lungs are exposed to oxidants in the air – anything from smoke to particulates,” Gilliland says. “The particles have metals attached to them. They create oxidative stress in the lungs.” Having strong defenses in the lungs wards off some of this damage.

If the tiny air spaces of the lungs were unfurled, they would cover an area the size of a tennis court, Gilliland explains. The lungs’ inner linings, however, are covered with a fluid teeming with antioxidants, forming a natural barrier. Although genetics also plays a part, researchers believe the fewer the antioxidants, the more vulnerable the lungs.
Research on nutrition has long indicated that eating plenty of fruit and vegetables is a good idea. The U.S. Department of Agriculture’s food guide pyramid suggests eating two to three servings of fruit and three to five servings of vegetables a day. Part of the fruit portions may come from juice.

Illustration by Edel Rodriguez

Turning a Brain Theory on its Ear
Slip of the Lips

Does the brain’s primary hearing center get activated when a person lipreads? That was the extraordinary claim of an article that caught Manbir Singh’s eye in the elite journal Science.

“The report claimed that silent lipreading localized in the same brain areas as spoken words, including the primary auditory cortex. We thought that didn’t make sense,” says the USC radiologist and biomedical engineer who, with colleagues from the Los Angeles-based House Ear Institute, has turned that proposition on its ear.

At the Los Angeles County+USC Imaging Science Center, Singh took MRI scans of the brains of people with normal hearing as they read lips off a video monitor. “With our very first subject, we could see that lipreading activates not the primary auditory cortex, but associative regions,” Singh says. These “associative regions” of the cortex process semantically rich, complex representations and language – not a single sensory modality. In other words, the areas Singh found to be active during lipreading would be triggered by words regardless of whether they are heard, read or signed.

Singh’s study confirmed that the brain is not somehow feeding those word judgments back to the primary auditory cortex – the region that initially analyzes the basic acoustic properties of sound. The House Ear Institute has asked Singh to run a series of functional MRI experiments to understand just how the brain does process lipreading and finger-spelling, and how the brains of the congenitally deaf organize differently from hearing brains. Singh’s recent study in NeuroReport is the first of many experiments exploring these issues.

– Matthew Blakeslee

Photo by Irene Fertik

Protein Power
Muscling in on Alzheimer’s

People with Alzheimer’s disease have something in common with patients suffering from a common, progressive muscle disease. Both, USC researchers have found, possess abnormally high levels of two enzymes involved in the production of amyloid-beta protein. Toxic amounts of amyloid-beta are found in both the brain plaque of Alzheimer’s patients and inside the muscle cells of people with inclusion-body myositis, or IBM.

The discovery brings medical science closer to the eureka point for IBM and perhaps for Alzheimer’s. Treatments for both diseases may not be very far behind. “If factors can be found that can decrease the enzyme, then hopefully amyloid-beta protein would no longer be produced in toxic amounts,” says principal investigator Valerie Askanas, a professor of neurology and pathology at the Keck School of Medicine of USC.

IBM is a crippling disease in which muscle fibers develop inflammations and begin to atrophy. “Patients with IBM become very frustrated because they begin falling suddenly, can’t grip things and – with progression – can’t get up and walk,” says Keck School colleague W. King Engel, who co-authored the paper published in the journal, The Lancet. “One of my patients is a carpenter who now can’t work because he’s afraid the hammer will fly out of his hands,” Engel says.

Millions of aging Americans who have or will develop Alzheimer’s disease also stand to benefit from the discovery. Not only are the pathogenic pathways of the two diseases similar, says Askanas, but the muscle cells that are affected in IBM patients are fairly easy to culture and investigate. “IBM muscle is a fantastic model that can easily be used to study amyloid-beta accumulation,” says Askanas. “You can’t take brain cells from Alzheimer’s patients and manipulate them to see what happens when you decrease these enzymes. But you can do that with IBM,” she says. “We can take fresh muscle biopsies, culture them and generate the affected muscle cells.”

Askanas has received a MERIT award from the National Institute of Aging to study IBM and its relationship to Alzheimer’s disease. She and Engel co-direct the USC Neuromuscular Center at Good Samaritan Hospital.

– Lori Oliwenstein

Photo by Michael Chaibaudo

Tienes Leche?

Legend has it the ghost weeps because, betrayed by her husband, she murdered her own children. In the latest installment of the super-successful “Got Milk?” ad campaign, though, La Llorona weeps because the carton’s empty. Everyone – including the bi-cultural Latino teens it targets – loves this Spanish-language spot now airing on mainstream stations. But will it wean trend-conscious youths off their sports drinks, sodas and iced teas? Ninety-nine percent fat chance, says USC marketing expert David W. Stewart. “Short of milk becoming a ‘cool’ drink in itself – and, in fact, being much more available than it is now – I don’t think you’re going to get people to drink very much more,” he augured in a February 7 segment of NPR’s “All Things Considered.”

Illustration by A.J. Garces