The Copper Connection

If you’re unlucky enough to get Lou Gehrig’s disease (aka, amyotrophic lateral sclerosis or ALS), treatment options are few. One drug, Riluzole, has been shown to marginally increase survival. Other drugs can be used to manage ALS symptoms, but there is no cure.

For more than a decade, Joe Beckman has been studying the chemistry of the disease. In some ways, his research has run counter to the conventional wisdom, but recent results from his lab suggest that he’s on the right track. With colleagues in Australia and the United Kingdom, he has demonstrated a treatment that, for the first time, dramatically extends the survival of laboratory mice that have been engineered to develop ALS.

Untreated, these animals live no longer than about 130 days. “We’ve extended survival past 278 days for some of these mice. That’s longer than anyone has ever shown,” says Beckman, Distinguished Professor in the College of Science at Oregon State.

As ALS proceeds, motor neurons in the central nervous system die. The result is a gradual loss of muscle function and paralysis. Up to half of people with the disease die within three years. Globally, about 140,000 people are diagnosed with ALS annually. In the United States, about 30,000 people live with the disease at any one time, according to the ALS Association.

Scientists have traced one of the causes of ALS to a mutant form of an enzyme called superoxide dismutase, or SOD1. Healthy forms of the enzyme act as an antioxidant by removing so-called “free radicals.” However, when SOD1 goes awry, it partially unfolds, loses zinc and copper ions and becomes toxic. The metal-free form of the enzyme has been shown to kill nerve cells.

Beckman and his team worked with mice that have a SOD1 mutation as well as a gene that carries copper into the enzyme. By giving the mice CuATSM, a copper-containing compound, orally and through the skin, they delayed progression of the disease and extended survival.

That result was surprising because the treatment also increased concentrations of SOD1. Other researchers have concluded that more SOD1 accelerates the disease. However, CuATSM treatment also “greatly reduced” unfolded forms of the enzyme, says Beckman.

“We believe that with further improvements, and following necessary human clinical trials for safety and efficacy, this could provide a valuable new therapy for ALS and perhaps Parkinson’s disease,” adds Beckman, who holds the Burgess and Elizabeth Jamieson Chair in Healthspan Research in Oregon State’s Linus Pauling Institute.