Javaneh Tamiji Archives | Research & Innovation

Professor Dorota Crawford's research shows misoprostol prevents cell communication

fmaquito — Fri, 09 Jul 2010 08:00:00 +0000

Drug has been linked to neurodevelopmental defects associated with autism

A 91��ɫ study has shown for the first time how the drug misoprostol, which has been linked to neurodevelopmental defects associated with autism, interferes with neuronal cell function.

It is an important finding because is similar in structure to naturally occurring prostaglandins, which are the key signalling molecules produced by fatty acids in the brain. The drug is used to prevent ulcers in people who take certain arthritis or pain medicines, including aspirin, that can cause ulcers. It protects the stomach lining and decreases stomach acid secretion.

Past clinical studies have shown an association between misoprostol and severe neurodevelopmental defects including autism symptoms. Those studies looked at cases in Brazil in which women misused the drug early in pregnancy in unsuccessful attempts to terminate their pregnancies.

The 91��ɫ study examined mouse neuronal cells to discover how the drug actually interferes at a molecular level with prostaglandins, which are important for development and communication of cells in the brain.

“Early in the first trimester of pregnancy, neuronal cells reach out to communicate with one another,” says Dorota Crawford, a professor in the School of Kinesiology & Health Science in 91��ɫ’s Faculty of Health. “Our study shows that misoprostol interferes with this process by increasing the level of calcium ions in neuronal extensions, which reduces the number and length of these extensions. It prevents the cells from communicating with each other. If changes in prostaglandin level alter the development or differentiation of cells, it may have a physiological impact.”

Left: Dorota Crawford

Crawford and Javaneh Tamiji, who undertook the research for her master’s thesis in the Neuroscience Graduate Diploma Program at 91��ɫ, co-authored a study published online in the journal Biochemical and Biophysical Research Communications: “Prostaglandin E2 and misoprostol induce neurite retraction in Neuro-2a cells”.

There is no indication that women in Canada are misusing misoprostol to terminate pregnancies, and in fact the drug is used safely for other purposes such as treatment and prevention of gastrointestinal ulcers. However, during early neuronal development the drug misoprostol or other environmental factors such as infections or inflammations, which can also increase the level of prostaglandins, may interfere with normal brain function, says Crawford.

Right: Javaneh Tamiji

Crawford and Tamiji focused on the drug misoprostol because they had evidence from clinical studies of the neurotoxic effects of the drug. They used misoprostol and the naturally occurring prostaglandins side by side in their study and found that both compounds produced the same effects on neuronal cell function.

The study shows that misoprostol interferes with the prostaglandin pathway in a dose-dependent manner – in other words, the higher the dose, the greater the problems created.

“What that indicates to us is whether it is infection that will activate it or whether it is the drug, it will cause the same effect,” says Crawford.

Now that it has been shown that misoprostol affects interaction between cells, the next step will be to do animal studies on mice to examine the physiological impacts on particular parts of the brain, she says.

Crawford’s lab is one of very few in the world that has adopted a multidisciplinary approach to the study of autism spectrum disorders, using molecular techniques to understand the link between causative biological factors (genes and environment) and the behavioural expression.

This research was funded by the . The provided equipment used in the study.

It has also received coverage on MedicalNewsToday.com:

A 91��ɫ study has shown for the first time how the drug misoprostol, which has been linked to neurodevelopmental defects associated with autism, interferes with neuronal cell function.

91��ɫ Professor Dorota Crawford, of the School of Kinesiology & Health Science in the Faculty of Science & Enginering, and graduate student Javaneh Tamiji, who undertook the research for her master’s thesis in the Neuroscience Graduate Diploma Program at 91��ɫ, co-authored a study published online in the journal Biochemical and Biophysical Research Communications: “Prostaglandin E2 and misoprostol induce neurite retraction in Neuro-2a cells”.

By Janice Walls, media relations officer

Republished courtesy of YFile– 91��ɫ’s daily e-bulletin.

The post Professor Dorota Crawford's research shows misoprostol prevents cell communication appeared first on Research & Innovation.

91��ɫ hosts its first Neuroscience Research Day

fmaquito — Mon, 21 Jun 2010 08:00:00 +0000

The first cohort of students graduating from 91��ɫ’s Neuroscience Graduate Diploma Program will present their leading-edge research today as part of the University’s first Neuroscience Research Day. The presentations will take place from 9am to 3:30pm in 163 Behavioural Sciences Building on 91��ɫ's Keele campus.

Fifteen students will offer summaries of their research. The students come to the program from different backgrounds, including computer science, psychology, biology, and kinesiology & health science.

"This day marks the culmination of two years of intense neuroscience studies for our first group of students," says Professor Doug Crawford (left), and the program’s coordinator. "They are a wonderful group and I am extremely proud of them"

Today’s presentations cover a wide range of approaches to neuroscience, ranging from research on molecular and cellular mechanisms in nerve cells and the relationship between the elements of neural systems, to the study of behaviour of whole organisms.

Psychology Professors Shayna Rosenbaum and Kari Hoffman have been hard at work coordinating the Neuroscience Research Day. “We began a neuroscience graduate diploma program at 91��ɫ in 2008. It combines the interests of the psychology, biology, and kinesiology & health sciences program,” says Rosenbaum. “This is the end of the second year of the program, which is a two-year consecutive program that is done in conjunction with the graduate students’ home department and their degree. [They are given a diploma in addition to their degree.] While the Neuroscience Research Day program is focused on the students, the event is also a celebration of the wide range of research interests among our neuroscience research faculty.”

Above: The class of 2010 and neuroscience faculty

The graduating students will be presenting a range of projects, says Rosenbaum, that draw on different methodologies. Some students will be showcasing work done using a molecular approach, while others will be presenting research that looks at neuroscience from a systems focus. Other students, says Rosenbaum, have relied on neuroimaging methods and some have done their research with patient populations. The breadth of projects that will be presented during the research day, says Rosenbaum, mirrors the program faculty's multidisciplinary approach to neuroscience.

Left: Shayna Rosenbaum

The following is a snapshot of some of the 15 research projects that will be presented today:

David Cappadocia (BSc Spec. Hons. ’08), is a second-year master's student working with Crawford. Cappadocia will present on his research into how the brain remembers different features of an object, so that when it is time to act on the object, it can be discriminated from other similar objects.

Caitlin Mullin (MSc ’08), a PhD student, is studying how different parts of the brain form representations of the visual world around us. Mullin is using transcranial magnetic stimulation to apply a brief magnetic pulse to a specific part of the brain. This temporarily deactivates the brain region, allowing Mullin to determine how it functions. Mullin is supervised by 91��ɫ psychology Professor Jennifer Steeves.

PhD student Krista Kelly will present her research that looks into the effects of losing one eye early in life. Specifically, Kelly is researching how that loss affects brain organization and visual ability. Working under the supervision of Steeves, Kelly is using functional brain imaging to correlate findings with behavioural measures of performance.

Master's students Javaneh Tamiji (BSc Spec. Hons. ’08) and Shannon Lozinsky are working with kinesiology Professor Dorota Crawford. They will present their research on the causes of autism, a disorder of the brain. Using state-of-the-art equipment funded by the , Tamiji and Lozinsky are investigating how environmental agents, such as drugs taken during early pregnancy, affect function and communication of cells in the brain. The goal of their project is to achieve a better understanding of what is different or missing in the brains of individuals with autism.

91��ɫ PhD student Debi Stransky (BSc Spec. Hons. ’06, MSc ’08) is investigating stereoscopic depth perception across a large range of depth offsets under the supervision of 91��ɫ psychology Professor Laurie Wilcox. There is convincing evidence that there is a separate depth processing mechanism for images that cannot be fused into a single percept. Stransky is determining the quality of depth perceived from such stimuli and if these percepts are subserved from distinct neural mechanisms. Her work is funded by a postgraduate fellowship from the Natural Sciences & Engineering Research Council of Canada (NSERC).

91��ɫ PhD student Inna Tsirlin (BSc Spec. Hons. ’04, MSc ’06) is studying depth perceptions from monocular occlusions. These are regions in a scene that are visible to one eye, but not to the other because they are occluded, for instance by objects in the foreground. For many years this information was considered noise. Tsirlin's work has shown that monocular occlusions help define the boundaries between objects and backgrounds, and can even provide quantitative depth information. Tsirlin is working under the supervision of Wilcox and her work is funded by a postgraduate fellowship from NSERC.

Left: Kari Hoffman

PhD student Stephanie Hornyak, who specializes in clinical neuropsychology, is investigating how brain regions communicate with each other to support spatial memory of well-known environments learned long ago. Under the supervision of 91��ɫ psychology Professor Shayna Rosenbaum, she has used an innovative method of combining functional MRI with multivariate statistics, which will help predict how brain networks may break down in patients who suffer from spatial disorientation.

91��ɫ master’s student Adrian Bartlett (BA Spec. Hons. ’08) is studying how the eye movements we use to scan the environment may shape the neural basis of object recognition. Using spectral analysis of neuronal population activity, his research has revealed that eye movements help coordinate the activity of neurons, leading to a stronger, more efficient code of what we’re viewing, Bartlett is the recipient of an NSERC Canada Graduate Scholarship and is supervised by psychology Professor Kari Hoffman.

“All the research being presented is very exciting and it is also an important year because 91��ɫ has acquired functional magnetic resonance imaging (fMRI) technology,” says Rosenbaum. “The day also offers students another forum for networking and will help them build future collaborations.”

Everyone in the University community is invited to attend the presentations. The deans of the , and Graduate Studies will also give presentations.

For more information, visit the Neuroscience Graduate Diploma Web site.

By Jenny Pitt-Clark, YFile editor

Republished courtesy of YFile– 91��ɫ’s daily e-bulletin.

The post 91��ɫ hosts its first Neuroscience Research Day appeared first on Research & Innovation.