The research, carried out by Dr Javier Bravo, and Professor John Cryan at the Alimentary Pharmabiotic Centre in University College Cork, along with collaborators from the Brain-Body Institute at McMaster University in Canada, demonstrated that mice fed with Lactobacillus rhamnosus JB-1 showed significantly fewer stress, anxiety and depression-related behaviours than those fed with just broth. Moreover, ingestion of the bacteria resulted in significantly lower levels of the stress-induced hormone, corticosterone.

“This study identifies potential brain targets and a pathway through which certain gut organisms can alter mouse brain chemistry and behaviour. These findings highlight the important role that gut bacteria play in the bidirectional communication between the gut and the brain, the gut-brain axis, and opens up the intriguing opportunity of developing unique microbial-based strategies for treatment for stress-related psychiatric disorders such as anxiety and depression,” said John F. Cryan, senior author on the publication and Professor of Anatomy and Principal Investigator at the Science Foundation Ireland funded Alimentary Pharmabiotic Centre, at UCC. The APC researchers included Dr Hélène Savignac and Professor Ted Dinan.

The researchers also showed that regular feeding with the Lactobacillus strain caused changes in the expression of receptors for the neurotransmitter GABA in the mouse brain, which is the first time that it has been demonstrated that potential probiotics have a direct effect on brain chemistry in normal situations. The authors also established that the vagus nerve is the main relay between the microbiome (bacteria in the gut) and the brain. This three way communication system is known as the microbiome-gut-brain axis and these findings highlight the important role of bacteria in the communication between the gut and the brain, and suggest that certain probiotic organisms may prove to be useful adjunct therapies in stress-related psychiatric disorders.

written by Brain Disorders and Therapy

For many poorly understood mental disorders, such as schizophrenia or autism, scientists often wish they could turn back the clock to uncover what has gone wrong in the brains of these patients, and how to right it before much brain damage ensues. But now, thanks to recent developments in the lab, that wish is coming true.

Researchers are using genetic engineering and growth factors to reprogram the skin cells of patients with schizophrenia, autism, and other neurological disorders and grow them into brain cells in the laboratory. There, under their careful watch, investigators can detect inherent defects in how neurons develop or function, or see what environmental toxins or other factors prod them to misbehave in the petri dish. With these “diseases in a dish” they can also test the effectiveness of drugs that can right missteps in development, or counter the harm of environmental insults.

“It’s quite amazing that we can recapitulate a psychiatric disease in a petri dish,” says neuroscientist Fred (Rusty) Gage, a professor of genetics at the Salk Institute for Biological Studies and member of the executive committee of the Kavli Institute for Brain and Mind (KIBM) at the University of California, San Diego. “This allows us to identify subtle changes in the functioning of neuronal circuits that we never had access to before.”

written by Brain Disorders and Therapy

Scientists say they have discovered a “maintenance” protein that helps keep nerve fibres that transmit messages in the brain operating smoothly.

The University of Edinburgh team says the finding could improve understanding of disorders such as epilepsy, dementia, MS and stroke.

In such neurodegenerative disorders, electrical impulses from the brain are disrupted.

This leads to an inability to control movement, and muscles wasting away.

The brain works like an electrical circuit, sending impulses along nerve fibres in the same way that current is sent through wires.

These fibres can measure up to a metre, but the area covered by the segment of nerve that controls transmission of messages is no bigger than the width of a human hair.

Signal failure

The scientists discovered that the protein Nfasc186 is crucial for maintaining the health and function of the segment of nerve fibres – called the axon initial segment (AIS) – that controls transmission of messages within the brain.

They found that the AIS and the protein within it are important in ensuring the nerve impulse has the right properties to convey the message as it should.

Professor Peter Brophy, director of the University of Edinburgh’s Centre for Neuroregeneration, said: “Knowing more about how signals in the brain work will help us better understand neurodegenerative disorders and why, when these illnesses strike, the brain can no longer send signals to parts of the body.”

Dr Matthew Nolan, of the university’s Centre for Integrative Physiology, said: “At any moment tens of thousands of electrical impulses are transmitting messages between nerve cells in our brains.

“Identifying proteins that are critical for the precise initiation of these impulses will help unravel the complexities of how brains work and may lead to new insights into how brains evolved.”

The work was funded by the Wellcome Trust and the Medical Research Council.

written by Brain Disorders and Therapy