June 3, 2011

Huntington’s disease: A medical intervention

( Ivanhoe Newswire) -- Huntington's disease is a devastating inherited neurogenetive disorder that is fatal. The disorder affects the central nervous system by causing progressive degeneration of cells in the brain, slowly impairing a person's ability to walk, think, talk, and reason. Now, researchers may have uncovered a novel approach to treat this incurable disease.

Huntington's disease can either be early or adult-onset, adult being the most common usually developed in a person's mid 30s and 40s. Symptoms may also resemble those of Parkinson's disease with rigidity and tremor.

Two international studies, one led by the University of Leicester, and the other a collaboration with Leicester led by scientists in the USA, hold out promise for slowing down the development of Huntington's disease and potentially, Alzheimer's and Parkinson's diseases. Reserachers found that by genetically targeting a particular enzyme in fruit flies, kynurenine 3-monooxygenase or KMO, a protein-coding gene, they arrested the development of the neurodegeneration, progressive loss of structure or function of neurons, associated with the disease. Furthermore, by manipulating metabolites in the KMO cellular pathway, they could manipulate the symptoms displayed by the flies.

"This work provides the first genetic and pharmacological evidence that inhibition of a particular enzyme- KMO - is protective in an animal model of this disease, and we have also found that targeting other points in this cellular pathway can improve Huntington's disease symptoms in fruit flies," Dr. Flaviano Giorgini, was quoted saying.  "This breakthrough is important as no drug currently exist that halt progression or delay onset of Huntington's disease."

The study found that both genetic and pharmacological inhibition of KMO reduces neurogeneration in a fruit fly model of the Huntington's disease, and that by feeding the fly's neuroactive kynureine pathway metabolites, the neurodegeneration can be modulated, highlighting the causation of these metabolites in this disease model. These positive results suggest it is time to consider testing the efficacy of KMO inhibitors, and potentially inhibitors of other kynurenine pathway enzymes, in Huntington's disease patients as well as sufferers of other neurodegenerative disorders.

"We are tremendously excited about these studies, as we hope that they will have direct ramifications for Huntington's disease patients," Dr. Giorgini said.

Sources: Current Biology, June 2011.