Amylotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease is a disease of the central nervous system. It is a nasty progression of neurodegeneration where motor neurons are lost. Over the course of the disease, control of muscles is slowly lost making it difficult to walk, breath, and swallow. People live 3-5 years with the disease and eventually die having to use a ventilator and be fed by others. Basically the endoplasmic reticulum does not have enough calcium which causes proteins to be folded incorrectly. When misfolded proteins accumulate, it leads to ER stress. The ER stress and misfolded proteins is not good for motor neurons and can kill them. However it is still not known for sure whether or not misfolded proteins produce motor neuron degeneration or are a result of it. Research still needs to be done in this area.
There is a fascinating apparent link between obesity (we have talked about this a lot in class) and ALS. As of now, not much is known as far as molecular pathways in obesity that could counteract the development or onset of ALS. However, what is known is that there does seem to be a correlation between BMI/obesity and the duration of ALS as well as the likelihood of getting ALS. A retroactive study of over 400 ALS patients was done comparing how long each person lived. It was seen that people with a BMI of 30 to 35 (mildly clinically obese) lived the longest and people with a BMI of 25 to 30 (obese) lived second longest. They lived longer than the malnourished and morbidly obese patients. This could be linked to the fact that ALS patients lose more weight than from the expected loss of muscle mass as well as burn more calories than is expected with their lack of significant physical activity.
One other study compared the body mass index of people when they were young and then up to three decades later. Of those who developed ALS, lower BMI at baseline was associated and with each 5 unit increase in the BMI, ALS rate decreased by 21%. The lower rate of ALS in those people with obesity was noticeable.
So I leave you with yet another disease that is not know fully. I is a nasty disease to have to live through. Luckily research is being done and avenues that we didn’t even think could exist do. This should show us that every option and link should be explored in hopes of a cure.