The root cause of amyotrophic lateral sclerosis (ALS) is unknown in most cases, though there are some genetic associations in a minority of patients that suggest possible lines of investigation. The condition is age-related in the sense that it typically emerges in the 50s and 60s. There is no effective treatment at this time and most patients have a short remaining life span of only a few years following onset. So it is good to see the potential for a treatment, not just for the patients, but also because it should help settle the matter of the cause of the condition, how it can be age-related but also occur in only a small number of people:
Researchers announced today that they have essentially stopped the progression of amyotrophic lateral sclerosis (ALS), or Lou Gehrig's disease, for nearly two years in one type of mouse model used to study the disease - allowing the mice to approach their normal lifespan. The findings, scientists indicate, are some of the most compelling ever produced in the search for a therapy for ALS. "We are shocked at how well this treatment can stop the progression of ALS." In decades of work, no treatment has been discovered for ALS that can do anything but prolong human survival less than a month.
The mouse model used in this study is one that scientists believe may more closely resemble the human reaction to this treatment, which consists of a compound called copper-ATSM. It's not yet known if humans will have the same response, but researchers are moving as quickly as possible toward human clinical trials, testing first for safety and then efficacy of the new approach. ALS was identified as a progressive and fatal neurodegenerative disease in the late 1800s. It's known to be caused by the death and deterioration of motor neurons in the spinal cord, which in turn has been linked to mutations in copper and zinc superoxide dismutases.
Copper-ATSM is a known compound that helps deliver copper specifically to cells with damaged mitochondria, and reaches the spinal cord where it's needed to treat ALS. This compound has low toxicity, easily penetrates the blood-brain barrier, is already used in human medicine at much lower doses for some purposes, and is well tolerated in laboratory animals at far higher levels. Any copper not needed after use of copper-ATSM is quickly flushed out of the body. Experts caution, however, that this approach is not as simple as taking a nutritional supplement of copper, which can be toxic at even moderate doses. Such supplements would be of no value to people with ALS.
Using the new treatment, researchers were able to stop the progression of ALS in one type of transgenic mouse model, which ordinarily would die within two weeks without treatment. Some of these mice have survived for more than 650 days, 500 days longer than any previous research has been able to achieve. In some experiments, the treatment was begun, and then withheld. In this circumstance the mice began to show ALS symptoms within two months after treatment was stopped, and would die within another month. But if treatment was resumed, the mice gained weight, progression of the disease once again was stopped, and the mice lived another 6-12 months. "We have a solid understanding of why the treatment works in the mice, and we predict it should work in both familial and possibly sporadic human patients. But we won't know until we try."