Human neural stem cells restore cognitive functions impaired by chemotherapy

February 15, 2015, University of California, Irvine
Charles Limoli, a UCI professor of radiation oncology. Credit: Steven Zylius/UC Irvine

Human neural stem cell treatments are showing promise for reversing learning and memory deficits after chemotherapy, according to UC Irvine researchers.

In preclinical studies using rodents, they found that transplanted one week after the completion of a series of chemotherapy sessions restored a range of cognitive functions, as measured one month later using a comprehensive platform of behavioral testing. In contrast, rats not treated with stem cells showed significant learning and memory impairment.

The frequent use of chemotherapy to combat multiple cancers can produce severe cognitive dysfunction, often referred to as "chemobrain," which can persist and manifest in many ways long after the end of treatments in as many as 75 percent of survivors - a problem of particular concern with pediatric patients.

"Our findings provide the first solid evidence that transplantation of human neural stem cells can be used to reverse chemotherapeutic-induced damage of healthy tissue in the brain," said Charles Limoli, a UCI professor of radiation oncology.

Study results appear in the Feb. 15 issue of Cancer Research, a journal of the American Association for Cancer Research.

Many chemotherapeutic agents used to treat disparate cancer types trigger inflammation in the hippocampus, a cerebral region responsible for many cognitive abilities, such as learning and memory. This inflammation can destroy and other cell types in the brain.

Additionally, these toxic compounds damage the connective structure of neurons, called dendrites and axons, and alter the integrity of synapses - the vital links that permit neurons to pass electrical and chemical signals throughout the brain. Limoli compares the process to a tree being pruned of its branches and leaves.

Consequently, the affected neurons are less able to transmit important neural messages that underpin learning and memory.

"In many instances, people experience that's progressive and debilitating," Limoli said. "For pediatric cancer patients, the results can be particularly devastating, leading to reduced IQ, asocial behavior and diminished quality of life."

For the UCI study, adult neural stem cells were transplanted into the brains of rats after . They migrated throughout the hippocampus, where they survived and differentiated into multiple neural cell types. Additionally, these cells triggered the secretion of neurotrophic growth factors that helped rebuild wounded neurons.

Importantly, Limoli and his colleagues found that engrafted cells protected the host neurons, thereby preventing the loss or promoting the repair of damaged neurons and their finer structural elements, referred to as dendritic spines.

"This research suggests that may one day be implemented in the clinic to provide relief to patients suffering from cognitive impairments incurred as a result of their cancer treatments," Limoli said. "While much work remains, a clinical trial analyzing the safety of such approaches may be possible within a few years."

Explore further: Stem cells restore cognitive abilities impaired by brain cancer treatment

Related Stories

Stem cells restore cognitive abilities impaired by brain cancer treatment

July 13, 2011
Human neural stem cells are capable of helping people regain learning and memory abilities lost due to radiation treatment for brain tumors, a UC Irvine study suggests.

Stem cell treatment may restore cognitive function in patients with brain cancer

July 13, 2011
Stem cell therapy may restore cognition in patients with brain cancer who experience functional learning and memory loss often associated with radiation treatment, according to a laboratory study published in Cancer Research, ...

Human stem cells repair damage caused by radiation therapy for brain cancer in rats

February 5, 2015
For patients with brain cancer, radiation is a powerful and potentially life-saving treatment, but it can also cause considerable and even permanent injury to the brain. Now, through preclinical experiments conducted in rats, ...

Fetal stem cell transplantation favorably impacts radiation-induced cognitive dysfunction

August 22, 2013
Patients receiving cranial irradiation treatment for brain cancer may find the treatment life-saving, but often suffer progressive and debilitating cognitive detriments, including spatial learning and memory deficits. The ...

Recommended for you

'Longevity protein' rejuvenates muscle healing in old mice

November 21, 2018
One of the downsides to getting older is that skeletal muscle loses its ability to heal after injury. New research from the University of Pittsburgh implicates the so-called "longevity protein" Klotho, both as culprit and ...

New mechanism controlling the master cancer regulator uncovered

November 21, 2018
Who regulates the key regulator? The Research Center for Molecular Medicine of the Austrian Academy of Sciences reports online in the journal Science about a newly discovered mechanism by which RAS proteins, central to cancer ...

AI matched, outperformed radiologists in screening X-rays for certain diseases

November 21, 2018
In a matter of seconds, a new algorithm read chest X-rays for 14 pathologies, performing as well as radiologists in most cases, a Stanford-led study says.

Study bridges a divide in cell aging in neurodegenerative diseases

November 21, 2018
Research from the University of Toronto has shown that in some neurodegenerative diseases, two hallmarks of cell aging – protein aggregation and a type of DNA instability – are linked. They were previously thought to ...

Machine learning can be used to predict which patients require emergency admission

November 20, 2018
Machine learning—a field of artificial intelligence that uses statistical techniques to enable computer systems to 'learn' from data—can be used to analyse electronic health records and predict the risk of emergency hospital ...

A Trojan horse delivery method for miRNA-enriched extracellular vesicles

November 20, 2018
A method for large-scale production of extracellular vesicles enriched with specific microRNAs (miRNAs) has been developed in the Wake Forest Institute for Regenerative Medicine (WFIRM) labs, offering a manufacturing standardization ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.