Newswise — Bristol-led research has identified specific drug targets within the neural circuits that encode memories, paving the way for significant advances in the treatment of a broad spectrum of brain disorders.

Loss of memory is a core feature of many neurological and psychiatric disorders including Alzheimer’s disease and schizophrenia. Current treatment options for memory loss are very limited and the search for safe and effective drug therapies has, until now, had limited success.

The research was done in collaboration with colleagues at the international biopharmaceutical company Sosei Heptares. The findings, published in Nature Communications, identify specific receptors for the neurotransmitter acetylcholine that re-route information flowing through memory circuits in the hippocampus. Acetylcholine is released in the brain during learning and is critical for the acquisition of new memories. Until now, the only effective treatment for the symptoms of cognitive or memory impairment seen in diseases such as Alzheimer’s is using drugs that broadly boost acetylcholine. However, this leads to multiple adverse side effects. The discovery of specific receptor targets that have the potential to provide the positive effects whilst avoiding the negative ones is promising.

Lead author, Professor Jack Mellor, from the University of Bristol’s Centre for Synaptic Plasticity, said: “These findings are about the fundamental processes that occur in the brain during the encoding of memory and how they may be regulated by brain state or drugs targeting specific receptor proteins. In the long-term, the discovery of these specific targets opens up avenues and opportunities for the development of new treatments for the symptoms of Alzheimer’s disease and other conditions with prominent cognitive impairments. The academic-industry partnership is important for these discoveries and we hope to continue working together on these projects.”

Dr Miles Congreve, Chief Scientific Officer at Sosei Heptares, added: “These important studies have helped us to design and select new, exquisitely targeted therapeutic agents that mimic the effects of acetylcholine at specific muscarinic receptors, without triggering the unwanted side effects of earlier and less-well targeted treatments. This approach has the exciting potential to improve memory and cognitive function in patients with Alzheimer’s and other neurological diseases.”

“It is fascinating how the brain prioritises different bits of information, working out what is important to encode in memory and what can be discarded. We know there must be mechanisms to pull out the things that are important to us but we know very little about how these processes work. Our future programme of work aims to reveal how the brain does this using acetylcholine in tandem with other neurotransmitters such as dopamine, serotonin and noradrenaline,” said Professor Mellor.

Paper:

‘Acetylcholine prioritises direct synaptic inputs from entorhinal cortex to CA1 by differential modulation of feedforward inhibitory circuits,’ by Palacios-Filardo, J., Udakis, M., Brown, G. A., Tehan, B. G., Congreve, M. S., Nathan, P. J., Brown, A. J. H. & Mellor, J. R. (2021) in Nature Communications.

10.1038/s41467-021-25280-5

Further information

 

The University of Bristol’s Centre for Synaptic Plasticity

The Centre for Synaptic Plasticity started as a joint venture between the Medical Research Council and the University of Bristol. Research is directed towards gaining an understanding of synaptic plasticity in both normal and disease states, such as epilepsy. Work within the Centre is carried out in a multidisciplinary and collaborative manner, with different research groups tacking different aspects of a particular question.

Based within the School of Medical Sciences and the Dorothy Hodgkin Building, groups within the Centre enjoy a recently refurbished research environment with access to state-of-the-art facilities and equipment.

The team behind this research is based within the University of Bristol’s Centre for Synaptic Plasticity under the umbrella of the School of Physiology, Pharmacology & Neuroscience and Bristol Neuroscience, and the project was a collaboration with researchers at Sosei Heptares. The work was supported by the Wellcome Trust and BBSRC.

About Sosei Heptares

Sosei Heptares is an international biopharmaceutical group focused on the discovery and early development of new medicines originating from our proprietary GPCR-targeted StaR® technology and structure-based drug design platform capabilities. It is advancing a broad and deep pipeline of novel medicines across multiple therapeutic areas, including neurology, immunology, gastroenterology and inflammatory diseases.

SH has established partnerships with some of the world’s leading pharmaceutical companies, including AbbVie, AstraZeneca, Biohaven, Genentech (Roche), GSK, Novartis, Pfizer and Takeda and additionally with multiple emerging technology companies. Sosei Heptares is headquartered in Tokyo, Japan with corporate and R&D facilities in Cambridge, UK.

“Sosei Heptares” is the corporate brand and trademark of Sosei Group Corporation, which is listed on the Tokyo Stock Exchange (ticker: 4565). Sosei, Heptares, the logo and StaR® are trademarks of Sosei Group companies.