A new study using genetically engineered mice and human cell and tissue samples has added to evidence that higher levels of inflammatory chemicals involved in fat metabolism occur in people with amyotrophic lateral sclerosis (ALS), the neuromuscular disorder, also known as Lou Gehrig’s disease.The study, which focused on genetic pathways involved in how spinal motor cells process fats, found that compared with people without ALS, those with the disorder have about 2.5-fold higher levels of arachidonic acid (image), a lipid commonly found in the fatty parts of meat and fish and that is known to spur on inflammatory processes needed to repair wounds or tissue damage. Notably, by tampering with the arachidonic acid pathway in mice bred to develop the biological hallmarks of ALS, the researchers say they were able to reduce the condition’s muscle-weakening symptoms in the mice--which experienced a 20%–25% increase in grip strength--and extend their survival by two to three weeks.