Press Releases & Research Commentary

Chances are if you're a senior managing your health, you've already had a conversation with your doctor about stroke risk. While many patients know the warning signs of stroke -- slurred speech, weakness on one side of the body, coordination problems, double vision, and headaches -- health care providers often fail to educate patients about their risk for silent or mini-strokes, which can cause progressive, permanent damage and lead to dementia.

A new study published in the Journal of Neuroscience, examined the effects of these so-called mini-strokes. They frequently are not diagnosed or detected by a doctor because a patient does not immediately present with stroke signs. Mini-strokes may lead to permanent neurological damage and increase risk for full blown stroke.

Maiken Nedergaard, MD, lead author of the study and professor of neurosurgery at the University of Rochester Medical Center, says at least half of individuals over the age of 60 will experience one mini-stroke in their lifetime. She calls the prevalence of mini-strokes "an epidemic."

The University of Rochester Medical Center has opened the doors on a new facility that will enable researchers to create, study, and ultimately use stem cells and their offspring in early-phase experimental human therapies. The Upstate Stem Cell cGMP Facility – which will be used by academic and private-sector scientists from across the state – was created with $3.5 million in support from the Empire State Stem Cell Board.

“One of the critical barriers to moving cell-based therapies into clinical trials is the requirement that these cells be manufactured in a facility that meets strict federal requirements,” said Steve Dewhurst, Ph.D., chair of the URMC Department of Microbiology and Immunology and principal investigator for the state grant. “Without this resource, much of this science remains stuck in the lab.”

A new study appearing today in the Journal of Neuroscience details for the first time how "mini-strokes" cause prolonged periods of brain damage and result in cognitive impairment. These strokes, which are often imperceptible, are common in older adults and are believed to contribute to dementia.

"Our research indicates that neurons are being lost as a result of delayed processes following a mini-strokes that may differ fundamentally from those of acute ischemic events," said Maiken Nedergaard, M.D., D.M.Sc., the lead author of the study and professor of Neurosurgery at the University of Rochester Medical Center. "This observation suggests that the therapeutic window to protect cells after these tiny strokes may extend to days and weeks after the initial injury."

When the era of regenerative medicine dawned more than three decades ago, the potential to replenish populations of cells destroyed by disease was seen by many as the next medical revolution. However, what followed turned out not to be a sprint to the clinic, but rather a long tedious slog carried out in labs across the globe required to master the complexity of stem cells and then pair their capabilities and attributes with specific diseases.

In a review article appearing today in the journal Science, University of Rochester Medical Center scientists Steve Goldman, M.D., Ph.D., Maiken Nedergaard, Ph.D., and Martha Windrem, Ph.D., contend that researchers are now on the threshold of human application of stem cell therapies for a class of neurological diseases known as myelin disorders -- a long list of diseases that include conditions such as multiple sclerosis, white matter stroke, cerebral palsy, certain dementias, and rare but fatal childhood disorders called pediatric leukodystrophies.

Stem cell biology has progressed in many ways over the last decade, and many potential opportunities for clinical translation have arisen, said Goldman. In particular, for diseases of the central nervous system, which have proven difficult to treat because of the brain's great cellular complexity, we postulated that the simplest cell types might provide us the best opportunities for cell therapy.

A previously unrecognized system that drains waste from the brain at a rapid clip has been discovered by neuroscientists at the University of Rochester Medical Center. The findings were published online August 15 in Science Translational Medicine.

The highly organized system acts like a series of pipes that piggyback on the brain's blood vessels, sort of a shadow plumbing system that seems to serve much the same function in the brain as the lymph system does in the rest of the body -- to drain away waste products.

"Waste clearance is of central importance to every organ, and there have been long-standing questions about how the brain gets rid of its waste," said Maiken Nedergaard, M.D., D.M.Sc., senior author of the paper and co-director of the University's Center for Translational Neuromedicine. "This work shows that the brain is cleansing itself in a more organized way and on a much larger scale than has been realized previously.

"We're hopeful that these findings have implications for many conditions that involve the brain, such as traumatic brain injury, Alzheimer's disease, stroke, and Parkinson's disease," she added.

A type of cell plentiful in the brain, long considered mainly the stuff that holds the brain together and oft-overlooked by scientists more interested in flashier cells known as neurons, wields more power in the brain than has been realized, according to new research published today in Science Signaling.

Neuroscientists at the University of Rochester Medical Center report that astrocytes are crucial for creating the proper environment for our brains to work. The team found that the cells play a key role in reducing or stopping the electrical signals that are considered brain activity, playing an active role in determining when cells called neurons fire and when they don't.

That is a big step forward from what scientists have long considered the role of astrocytes -- to nurture neurons and keep them healthy.

"Astrocytes have long been called housekeeping cells -- tending to neurons, nurturing them, and cleaning up after them," said Maiken Nedergaard, M.D., D.M.Sc., professor of Neurosurgery and leader of the study. "It turns out that they can influence the actions of neurons in ways that have not been realized."