Study shows reduction in brain injury after stroke patients were treated with their own stem cells

Illustration showing the mechanism of an ischemic stroke. In an ischemic stroke, blood supply to part of the brain is decreased, leading to dysfunction of that area of the brain. Here, a blood clot is the reason for restricted blood flow.

Stroke is the third leading cause of death and serious long-term disability and affects nearly 800,000 Americans a year, with someone in the U.S. suffering a stroke every 40 seconds. Roughly 87% of all strokes are ischemic strokes, meaning that a clot blocks blood flow to the brain. Unfortunately 90% of those who suffer an ischemic stroke also end up suffering from weakness or paralysis to one side of the body.

A study conducted by Muhammad Haque, Ph.D. and Sean Savitz, M.D. at The University of Texas Health Science Center at Houston (UTHealth) found that treating patients with stem cells from their own bone marrow could lead to a reduction in brain injury after a stroke caused by a blood clot.

For this study, there were 37 patients from ages 18 to 80. While all received the standard stroke treatment and rehabilitation follow-up, 17 patients whose strokes were the most severe received a bone marrow stem cell therapy. To measure any improvement, the UTHealth team used 3D brain imaging of the patients obtained from MRI scans. They used these images to compare changes in white matter of those treated with their own bone marrow stem cells to those who were not treated.

White matter is a specific type of tissue in the brain that is critical for motor function because it is responsible for carrying movement-related information to the spinal cord.

Three months after the stroke, the MRI scans of each patient showed the expected decrease after a stroke. However, scans taken 12 months after the stroke occurred showed an improvement on average in the 17 patients who received bone marrow cell therapy.

In a press release from UTHealth, Dr. Haque elaborates on what these results could mean for developing treamtents for stroke patients.

“We envision that future clinical trials might be directed toward identifying white matter protection or repair as an important mechanistic target of efficacy studies and potency assays for bone marrow cell therapies.”

The full results to this study were published in STEM CELLS Translational Medicine.

3D brain model shows potential for treatment of hypoxic brain injuries in infants

Image of 3D brain cultures in the Sergiu Pasca lab.
Photo courtesy of Timothy Archibald.

A baby’s time in the womb is one of the most crucial periods in terms of its development. The average length of gestation, which is defined as the amount of time in the womb from conception to birth, is approximately 40 weeks. Unfortunately, for reasons not yet fully understood, there are times that babies are born prematurely, which can lead to problems.

These infants can have underdeveloped portions of the brain, such as the cerebral cortex, which is responsible for advanced brain functions, including cognition, speech, and the processing of sensory and motor information. The brains of premature infants can be so underdeveloped that they are unable to control breathing. This, in combination with underdeveloped lungs, can lower oxygen levels in the blood, which can lead to hypoxic, or low oxygen related, brain injuries.

In a previous study, doctors Anca and Sergiu Pasca and their colleagues at Stanford developed a technique to create a 3D brain that mimics structural and functional aspects of the developing human brain.

Using this same technique, in a new study with the aid of CIRM funding, the team grew a 3D brain that contained cells and genes similar to the human brain midway through the gestational period. They then exposed this 3D brain to low oxygen levels for 48 hours, restored the oxygen level after this time period, and observed any changes.

It was found that progenitor cells in a region known as the subventricular zone, a region that is critical in the growth of the human cortex, are affected. Progenitor cells are “stem cell like” cells that give rise to mature brain cells such as neurons. They also found that the progenitor cells transitioned from “growth” mode to “survival” mode, causing them to turn into neurons sooner than normal, which leads to fewer neurons in the brain and underdevelopment.

In a press release, Dr. Anca Pasca is quoted as saying,

“In the past 20 years, we’ve made a lot of progress in keeping extremely premature babies alive, but 70% to 80% of them have poor neurodevelopmental outcomes.”

The team then tested a small molecule to see if it could potentially reverse this response to low oxygen levels by keeping the progenitor cells in “growth” mode. The results of this are promising and Dr. Sergiu Pasca is quoted as saying,

“It’s exciting because our findings tell us that pharmacologically manipulating this pathway could interfere with hypoxic injury to the brain, and potentially help with preventing damage.”

The complete findings of this study were published in Nature.