SLN and amyotrophic lateral sclerosis: In a recently published study, the levels of sarcolipin, an important regulator of SERCA activity in muscle fibers, appeared to be upregulated in SOD1 transgenic mice,197 triggering a mitochondrial reprogramming event which determines a transition of skeletal muscle for glycolytic to oxidative metabolism.198 Such modifications correlate well with some of the evidence discussed above, supporting the existence of metabolic dysfunction and early mitochondrial failure in ALS pathogenesis.