For instance, the upregulation of some circulating cytokines, such as IL-6, IL-8, IL-10, G-CSF and TNF-α, has been linked to exercise [92], and others, including IL-6 and TNF-α, are elevated in a hypoxia status [93], which is a feature frequently found in ALS patients. Here, CXCL8 is linked to amyotrophic lateral sclerosis.