Within each and every one of our cells is a molecular machine that recognises and degrades broken down proteins. It is similar in concept to a garbage disposal unit. In MND, protein garbage piles up in the cell and causes all sorts of molecular sized problems. A protein named Dorfinhas been known to recognise and label junk protein to be mulched or degraded. Scientists from Nagoya University have studied the effects of increasing the amount of Dorfin in mutant SOD1 MND mice. Increasing the amount of Dorfin decreased the amount of SOD1 piled up in the cell and extended the lifespan of mice. This suggests that stimulating the cell to take out the trash and not letting the junk pile up may be an effective treatment of MND. Similarly, researchers from the University of Texas have shown that using a drug that stimulates one of the cells garbage disposal systems (called autophagocytosis) reduces the amount of accumulated TDP-43 in cells grown in the laboratory.
The accumulation of junk protein is also linked to a number of neurodegenerative diseases (not just MND) including Alzheimer's disease, Parkinson's disease and Huntington's disease. With this similarity in mind a group of scientists from the UK, Russia and Japan looked at the effect of the drugs Methyl Blue and Dimebon (in phase III clinical trials for Alzheimer's disease) on nerve cells grown in the laboratory. The treated cells had less accumulation of TDP-43 inside them suggesting that it may also be worthwhile trialling these drugs fo r the treatment of MND.
Source: International MND research update -September 2009, Dr Justin Yerbury for MNDRIA