NFKB1 and sarcopenia: Elevated bilirubin, as a potent endogenous antioxidant, mitigates UHR-induced sarcopenia progression through multifaceted mechanisms including direct ROS scavenging, AMPK signaling pathway-dependent activation of the Nrf2 antioxidant system, suppression of NF-κB-mediated inflammatory responses, and enhancement of mitochondrial function (9, 47).