Monday, November 14, 2011
Health Canal, 11/10/2011
The future of drug design lies in developing therapies that can target specific cellular processes without causing adverse reactions in other areas of the nervous system.
Scientists at the Universities of Bristol and Liège in Belgium have discovered how to design drugs to target specific areas of the brain.
The research, led by Professor Neil Marrion at Bristol’s School of Physiology and Pharmacology and published in this week’s Proceedings of National Academy of Sciences USA (PNAS), will enable the design of more effective drug compounds to enhance nerve activity in specific nerves…
The researchers have been using a natural toxin found in bee venom, called apamin, known for its ability to block different types of SK channel. SK channels enable a flow of potassium ions in and out of nerve cells that controls activity. The researchers have taken advantage of apamin being able to block one subtype of SK channel better than the others, to identify how three subtype SK channels [SK1-3] can be selectively blocked.
Neil Marrion, Professor of Neuroscience at the University, said: “The problem with developing drugs to target cellular processes has been that many cell types distributed throughout the body might all have the same ion channels. SK channels are also distributed throughout the brain, but it is becoming obvious that these channels might be made of more than one type of SK channel subunit. It is likely that different nerves have SK channels made from different subunits. This would mean that developing a drug to block a channel made of only one SK channel protein will not be therapeutically useful, but knowing that the channels are comprised of multiple SK subunits will be the key.”
The study’s findings have identified how SK channels are blocked by apamin and other ligands. Importantly, it shows how channels are folded to allow a drug to bind. This will enable drugs to be designed to block those SK channels that are made of more than one type of SK channel subunit, to target the symptoms of dementia and depression more effectively…