Memories restored in mice

Research published last week in Nature shows that decreasing the effects of a gene called HDAC can boost thinking skills and memory in mice. The researchers, led by Dr Ji-Song Guan at the Massachusetts Institute of Technology (MIT), US, hope that with further research the drug used to inhibit HDAC could be used to treat Alzheimer's disease.

Professor Li-Huei Tsai, co-author of the study said: 'This is exciting because more potent and safe drugs can be developed to treat Alzheimer's by targeting this HDAC. However, treatment for humans is still a decade or more away.' Alzheimer's is a progressive neurological disorder that affects a person's memory, judgment, and ability to use language. It affects over 400,000 people in the UK and is caused by damage and death of nerve cells in the brain.

The team studied mice with Alzheimer's-like symptoms, and tested their behaviour, thinking, learning and memory skills. They found that after injecting the mice with a HDAC inhibitor, their memory improved, and they were able to access forgotten information. The HDAC (histone deacetylase) gene controls a number of other genes, many of which are thought to be involved in maintaining 'synaptic plasticity', the ability of the connection, or synapse, between two neurons to change in strength. Nerve cells in the brain communicate with each other to transmit and store information. Many scientists believe that synaptic plasticity is essential for nerve cell functioning and memory formation.

The researchers say that inhibiting HDAC has the potential to boost synaptic plasticity, synapse formation and memory formation. Their next step is to develop new HDAC inhibitors and test their function for human diseases.

HDAC inhibitors are in trials to treat Huntingdon's disease, and are on the market to treat some cancers, but as this study is in mice, it will be many years before researchers will know if the drugs are safe and could be of any benefit to people with Alzheimer's.

Rebecca Wood, chief executive of the Alzheimer's Research Trust said that 'this is promising research which improves our understanding of memory loss in Alzheimer's'. She added: 'We need to do more research to investigate whether developing treatments that control this gene could benefit people with Alzheimer's'.