Transfers of the immune cell eosinophils from young mice into old mice resolved inflammation, rejuvenated the immune system, and improved body composition and physical fitness.

The hormone fibroblast growth factor 21 is made in the liver in response to increased levels of sugar; it targets glutamatergic neurons in the brain to lower sugar intake and cravings for sweets.

Non-alcoholic fatty liver disease is linked to neurological problems. The adipokine lipocalin-2 causes neuroinflammation and is produced exclusively by the liver, more so in those with fatty liver.

Precision DNA editing in the nucleus has previously been unable to reach the mitochondrial genome; a new mitochondrial editor has been discovered, which is engineered from a bacterial toxin.