Sea anemones provide potential new MS treatment
27th August, 2012
A toxin from the Caribbean sea anemone, Stichodactyla helianthus, ShK, was identified as a potassium channel blocker by USA scientists in 1995. Potassium channels are found on many different cell types and come in many different forms. They are involved in maintaining the electrical balance of ions between the inside and outside of cells.
Soon after the discovery of ShK, Prof Norton at Monash University and his collaborators at the University of California Irvine, developed a synthetic version of the ShK molecule and found that it blocked a particular type of potassium channel, called Kv1.3, found on immune cells.
With potassium channels controlling many functions in the human body, developing a drug that can block a specific function without unwanted side effects could prove difficult. However, the Kv1.3 potassium channel is found only on T-cells and in the nose. Because of this limited distribution, the researchers were able to develop a highly selective immune suppressing compound based on the sea anemone peptide.
In work published in the Journal of Pharmacology and Experimental Therapeutics in May this year, the compound, known as ShK-186, showed promise in suppressing the immune response in animal models of MS and rheumatoid arthritis and could alter the activity of human immune cells (specifically T-cells) in the test-tube.
‘Our research shows that we may be able to effectively treat MS while protecting the immune system,’ Prof Norton said.
‘The next step is to find out what dose works best to treat MS and at what stage of the disease treatment should begin.’
The compound will be tested in a phase I clinical trial in the Netherlands. Phase I trials establish dosage and safety in a small number of human subjects. If successful this would then lead to Phase II trials in larger groups of people with MS to test efficacy in suppressing MS relapses.
For further details of the research see publications in Toxicon and Journal of Pharmacology and Experimental Therapeutics
- 25/8/12 - ABC News [view footage here]