Gene therapy helps functional recovery after stroke

Gene therapy helps functional recovery after stroke

First published on ScienceDaily.com

A new gene therapy turns glial cells — abundant support cells in the brain — into neurons, repairing damage that results from stroke and significantly improving motor function in mice. A paper describing the new therapy, which uses the NeuroD1 gene, appears online in the journal Molecular Therapy. Once further developed, this NeuroD1-based gene therapy could potentially be used to treat stroke, which is a leading cause of disability in the U.S., with 800,000 new stroke patients every year.

“The current treatment for stroke has a narrow time window, typically within a few hours after the occurrence of stroke,” said lead author Yuchen Chen, a postdoctoral fellow at Penn State. “Many patients cannot receive the treatment in time and as a result, often suffer from permanent disability caused by irreversible neuronal loss. There is an urgent need to develop a new therapy to regenerate new neurons and restore lost brain functions among stroke patients.”

The human brain has approximately 86 billion neurons. While mini-strokes can be tolerated, moderate stroke involving the loss of billions of neurons leaves detrimental effects that do not spontaneously recover.

“So, the critical question that is still unanswered in the neuroregeneration field is how can we regenerate billions of new neurons in a patient’s brain after stroke?” said Gong Chen, professor of biology and Verne M. Willaman Chair in Life Sciences at Penn State and leader of the research team. “The biggest obstacle for brain repair is that neurons cannot regenerate themselves. Many clinical trials for stroke have failed over the past several decades, largely because none of them can regenerate enough new neurons to replenish the lost neurons.”

Gong Chen and his team pioneered a new approach to regenerate functional neurons using glial cells, a group of cells surrounding every single neuron in the brain that provide essential support to neurons. Unlike neurons, glial cells can divide and regenerate themselves, especially after brain injury.

“I believe that turning glial cells that are already present in the brain into new neurons is the best way to replenish the lost neurons,” said Gong Chen. “These glial cells are the neighbors of the dead neurons in the brain and are likely to share the same ancestral cellular lineage.”

Gong Chen’s team previously reported that a single genetic neural factor, NeuroD1, could directly convert glial cells into functional neurons inside mouse brains with Alzheimer’s disease, but the total number of neurons generated was limited. The research team believed that this limited regeneration was due to the retroviral system used to deliver NeuroD1 to the brain. In the current study, the research team used the AAV viral system, which is now the first choice for gene therapy in the nervous system, to deliver NeuroD1 into mouse motor cortex that had suffered from stroke.
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Image: Pixabay

Take long naps? Sleep more than nine hours a night? Your stroke risk may be higher

Take long naps? Sleep more than nine hours a night? Your stroke risk may be higher

First published on ScenceDaily.com

People who take long naps during the day or sleep nine or more hours at night may have an increased risk of stroke, according to a study published in the December 11, 2019, online issue of Neurology®, the medical journal of the American Academy of Neurology.

People who took a regular midday nap lasting more than 90 minutes were 25 percent more likely to later have a stroke than people who took a regular nap lasting from one to 30 minutes. People who took no naps or took naps lasting from 31 minutes to one hour were no more likely to have a stroke than people who took naps lasting from one to 30 minutes.

“More research is needed to understand how taking long naps and sleeping longer hours at night may be tied to an increased risk of stroke, but previous studies have shown that long nappers and sleepers have unfavorable changes in their cholesterol levels and increased waist circumferences, both of which are risk factors for stroke,” said study author Xiaomin Zhang, MD, PhD, of Huazhong University of Science and Technology in Wuhan, China. “In addition, long napping and sleeping may suggest an overall inactive lifestyle, which is also related to increased risk of stroke.”

The study involved 31,750 people in China with an average age of 62. The people did not have any history of stroke or other major health problems at the start of the study. They were followed for an average of six years. During that time, there were 1,557 stroke cases.

The people were asked questions about their sleep and napping habits. Midday napping is common in China, Zhang said. Eight percent of the people took naps lasting more than 90 minutes. And 24 percent said they slept nine or more hours per night.

The study found that people who sleep nine or more hours per night are 23 percent more likely to later have a stroke than people who sleep seven to less than eight hours per night. People who sleep less than seven hours per night or between eight and less than nine hours per night were no more likely to have a stroke than those who slept from seven to less than eight hours per night.

The results were all adjusted for other factors that could affect the risk of stroke. These include high blood pressure, diabetes and smoking.

People who were both long nappers and long sleepers were 85 percent more likely to later have a stroke than people who were moderate sleepers and nappers.

The researchers also asked people about how well they slept. People who said their sleep quality was poor were 29 percent more likely to later have a stroke than people who said their sleep quality was good.

Of the long nappers, 1 percent of cases per person-years later had a stroke, compared to 0.7 percent of cases per person-years of the moderate nappers. The numbers were the same for the long and moderate sleepers, with 1 percent of cases per person-years compared to 0.7 percent of cases per person-years having a stroke.

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Image: Pixabay

Stroke patients relearning how to walk with peculiar shoe

Stroke patients relearning how to walk with peculiar shoe

First published on ScienceDaily.com

A therapeutic shoe engineered to improve stroke recovery is proving successful and expected to hit the market by the end of the year. Clinical trials have been completed on the U.S. patented iStride device, which is licensed by Moterum LLC, a startup company located in the University of South Florida (USF) Research Park. Its results were just published in the Journal of NeuroEngineering and Rehabilitation.

Stroke sufferers experience muscle weakness or partial paralysis on one side of the body, which greatly impacts how they walk, known as gait. Gait asymmetry is associated with poor balance, a major cause of degenerative issues that make individuals more susceptible to falls and injuries.

The iStride device is strapped over the shoe of the good leg and generates a backwards motion, exaggerating the existing step, making it harder to walk while wearing the shoe. The awkward movement strengthens the stroke-impacted leg, allowing gait to become more symmetrical once the shoe is removed. The impaired foot wears a matching shoe that remains stationary.

“The backward motion of the shoe is generated passively by redirecting the wearer’s downward force during stance phase. Since the motion is generated by the wearer’s force, the person is in control, which allows easier adaptation to the motion,” said developer Kyle Reed, PhD, associate professor of mechanical engineering at USF. “Unlike many of the existing gait rehabilitation devices, this device is passive, portable, wearable and does not require any external energy.”

“The importance of over-ground gait training has been emphasized in previous studies,” said Seok Hun Kim, PT, PhD, research collaborator and associate professor in the School of Physical Therapy and Rehabilitation Sciences in the USF Health Morsani College of Medicine. “However, the training options available after stroke are very limited. This novel device allows gait rehabilitation in the environment of daily activities.”

The trial included six people between ages 57 and 74 who suffered a cerebral stroke at least one-year prior to the study. They all had asymmetry large enough to impact their walking ability. Each received twelve, 30-minute gait training sessions for four weeks. With guidance from a physical therapist, the patients’ gait symmetry and functional walking were measured using the ProtoKinetics Zeno Walkway system in the Human Functional Performance Laboratory at USF.

All participants improved their gait’s symmetry and speed. That includes how long it takes to stand up from a sitting position and walk, as well as how long it takes to walk to a specific location and distance traveled within six minutes. Four improved the percentage of time spent in a gait cycle with both feet simultaneously planted on the ground, known as double limb support. As far as the other two that didn’t improve, one started the study with severe impairment, while the other was highly functional. It’s also important to note that three participants joined the study limited to walking in their homes. Following the trial, two of them could successfully navigate public venues.
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Image: Pixabay

World Stroke Campaign Awards: Nominations for 2019 World Stroke Day campaigns are open

World Stroke Campaign Awards: Nominations for 2019 World Stroke Day campaigns are open

World Stroke Campaign Awards recognize key achievements in raising awareness of the World Stroke Day campaign themes and messages. Nominations for 2019 World Stroke Day campaigns are open until 19th December 2019.

To apply for an award, please visit the World Stroke Campaign website, click on the relevant award category and complete the online application form.

Award winners are featured on the World Stroke Campaign website, media and social media channels and will receive free annual membership of the World Stroke Organization which facilitates free access to the International Journal of Stroke and World Stroke Academy education resources.

For more information, contact Sarah Belson, WSO International Development Manager at sarah.belson@stroke.org.uk

PRESTIGE-AF second annual meeting held in Graz, Austria on 6th December

PRESTIGE-AF second annual meeting held in Graz, Austria on 6th December

First published on https://www.prestige-af.org/

Another year, another successful annual meeting. Hosted by PRESTIGE-AF partners, Medizinische Universitat Graz (MUG), the PRESTIGE-AF consortium convened in the idyllic and picturesque town of Graz in Austria on the 6th December for one full day of intense presentations, parallel session discussions and Scientific Advisory Board feedback.

The day started early at 8am, inviting the medical students of MUG to a seminar on the PRESTIGE-AF project. Dr Thomas Gattringer who is Additive Specialist Neurological Intensive Care at MUG, focussed his talk on the diagnosis and treatment of haemorrhagic stroke. With final remarks discussing the identified gaps in treatment guidelines, Dr Gattringer provided a smooth segue for Prof Roland Veltkamp to speak about the PRESTIGE-AF study. Coordinator of PRESTIGE-AF and Chair of Stroke Medicine at Imperial College London (UK), Prof Veltkamp explained to the students what PRESTIGE-AF, as an EU-funded, international collaborative research study, hopes to achieve in closing these gaps in stroke treatment guidelines and the expected research and patient impacts.

After these talks, the PRESTIGE-AF consortium gathered and work group leaders provided updates on their research progress from the past year. A well-deserved lunch brought in the afternoon parallel sessions. With one group discussing predictive modelling and the other clinical trial coordination, partners used the time to ask each other questions and clarify the particulars around the PRESTIGE-AF clinical trials including protocols, responsibilities and technical requirements.

You can read the full article here.