SPSB1 and Sepsis: Copper accumulation also activates the NF-κB pathway (Deng et al., 2023; Liu et al., 2020b), which induces an increase in SPRY domain-containing SOCS box protein 1 (SPSB1) and has been found to lead to muscle atrophy and weakness in mice with sepsis (Li et al., 2023c).