Is Nutrition The Future of Brain Health?

22 Oct 2015 --- We take it for granted that our body can regenerate cells that become injured or simply wear out and die. For most of the 20th century, however, scientists were convinced that one organ—the brain—lacked that ability. Shortly after birth, they thought, our brains had as many neurons as they were ever going to have, and if we lost brain cells because of injury or aging, we were never going to make more of them.

It wasn't until 1998 that the existence of human neural stem cells that could become a variety of different types of brain cells—growing on the lining of the brain's internal cavities and in the hippocampus was discovered.

"When they grow, they make copies of themselves, which is unusual," says Steindler. "They make more daughter cells that are involved in memory, learning and mood function, and have an innate ability to repair damaged tissue."

The question was how could these neural stem cells be stimulated to produce more healthy cells without overproducing and creating tumors—and how could they continue to make cells as they aged? A few years ago, Steindler began investigating a new angle: nutrition. "Food is medicine," he says. "Nutrition has the ability to affect many of those pathways at the same time."

Steindler will continue to explore those pathways as the new director of the Neuroscience and Aging Laboratory at the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts.

Steindler's focus on the link between nutrition and neurodegenerative diseases is unique in the field. Brent Reynolds, professor of neurosurgery at the University of Florida, says, "Steindler is an incredibly innovative scientist," he says. "He is on the cutting edge of so many things. What happens more often than not is the rest of the scientific community catches up with him five years later."

Reynolds was excited when he heard that Steindler had been able to discover neural stem cells in humans. "It was a huge step. So often we do things in rodents that don't translate to humans," he says. "When you demonstrate that, you are now saying that everything we've done in rodents is now possible to translate."

Reynolds will continue to collaborate with Steindler on his research at Tufts, which will focus on how to retain the ability of these stem cells to repair and regenerate cells as they get older.

"What's become very clear is that the regenerative capacity diminishes as you age," says Reynolds. "The question Steindler will probably ask and answer is how do these nutritional requirements change and how do they tie into the regenerative ability. Once we answer that question, we can ask how we alter nutrition to achieve that."

To home in on those questions, Steindler has focused on the role that inflammation plays in the aging of stem cells, as well as in neurodegenerative diseases such as Alzheimer's and Parkinson's. Research has shown that inflammation produces small proteins, or cytokines, in brain cells. Two of these types of proteins—amyloid and tau proteins—have been associated with Alzheimer's disease.

By changing diet and nutrition, patients may be able to limit inflammation of brain tissue and prevent or even reverse these degenerative diseases by giving neural stem cells the ability to heal the damage.

"All of the bioactive components in our diet play a role in how cells can battle this tendency to become inflamed," says Steindler. In particular, he is experimenting with three antioxidants, which he suspects may need to be consumed in higher doses as we age in order to ensure healthy stem cell function—ECGC, found in green tea; curcumin, found in turmeric; and sulforaphane, found in broccoli, Brussels sprouts and other vegetables. All three of these chemical compounds are currently under investigation at the HNRCA.

Alongside this research, Steindler is ramping up the laboratory at Tufts to better investigate the properties of these nutritional supplements. He hopes drawing upon the expertise of his colleagues will help determine the most effective changes in diet to attack the inflammation that leads to brain degeneration as well as cancer.

"Truly, Tufts and the HNRCA are leaders in these things," says Steindler, crediting his predecessor at the neuroscience lab, Jean Mayer University Professor Irwin Rosenberg. "I am hoping to collaborate extensively in order to get these new therapeutic reagents into a clinical setting. All of the diet and nutrient therapies we study seem quite able to slow down the diseases—and possibly, if done right, even prevent them."