Scientific journal Nature has reported that scientists in the US have come some way in successfully reversing the effects of Alzheimer’s disease with experimental drugs.

Alzheimer’s disease poses a profound challenge for both sufferers and their families as well as healthcare services worldwide, its incidence increasing year on year.

Scientists in the US researching the genetic expression of the disease have developed a potentially revolutionary treatment which may potentiate the development of the first course of treatment capable of reversing the effects of the disease. Current pharmaceutical treatments such as memantine and NMDA receptor antagonists have shown little to no clinical effectiveness possessing no statistically significant ability to slow the progression of the disease. The current treatment strategy is targeted simply to reduce the severity of the diseases characteristics.

Scientific opinion on the precise cause of AD has traditionally remained split, however it is now widely regarded that the disease is caused by aggregation of amyloid beta leading the formation of fibrillar amyloid plaques and hyperphosphorylated tau complexes within the brain. These aggregates disintegrate the microtubules within individual neurons destroying their transport systems, leading terminally to cell death.

Known as HDAC inhibitors, the drugs in development selectively reshape the DNA architecture that controls the expression of certain genes within the brain associated with the formation of the characteristic ‘tangles’ and plaques’. Current trials are targeted towards a novel category of genes identified to be fundamentally important in the formation of memory. Thus far, experiments undertaken on mice have shown restoration in long-term memory and actual improvements in the ability to learn new tasks.

Alzheimer’s sufferers display reduced capacity to respond to essential stimuli in the formation of memories. This facet, termed ‘plasticity’ has been the subject of extensive research most recently in relation to targeted genetic modulators. The new drug in question acts upon a genetic regulator known as histone deacetylase 2 (HDAC2) which regulates the expression of a plethora of genes fundamental in establishing and maintaining plasticity.

Lead researcher Professor Li-Huei Tsai explained: “It brings about long-lasting changes in how other genes are expressed, which is probably necessary to increase numbers of synapses and restructure neural circuits, thereby enhancing memory… to our knowledge, HDAC inhibitors have not been used to treat Alzheimer’s disease or dementia.”

Whilst the data collected so far is indeed promising and suggestive of a novel therapeutic treatment for Alzheimer’s disease in humans, the development of selective human HDAC2 inhibitors remains a monumental task. The ramifications of a successful human trial would be profound however this remains at least ten years away. The development of new pharmaceuticals is both exceptionally time consuming and expensive. Considering the treatment’s potential ability to manipulate a candidate’s genetic profile and its implications on protein expression in the brain, it must be understood that any such treatment requires extensive research and testing before it can progress to phase three human trials.

Facing a relative drought in encouraging experimental data, the use of HDAC2 inhibitors is indeed promising. If the data is accurate and this success can be carried over into human trials, the ability not simply to slow or halt, but to reverse disease progression, would be a quantum leap in therapeutic treatment. Whilst the development of safe selective human HDAC2 inhibitors remains a challenge, in a world where funding is the be all and end all, the publication of this data will hopefully potentiate research and development. It cannot go without note that the pharmaceutical giant who offers its brand to any potentially successful drug will stand to make an incredible amount of money.