AOPEP and Atrophy: Additionally, research has identified pathogenic genes related to muscle atrophy, such as AOPEP (Fevga et al., 2022; Garavaglia et al., 2022; Menden et al., 2022; Zech et al., 2022; Lin et al., 2023; Thomsen et al., 2023), suggesting a potential novel approach for patients with cachexia to improve muscle symptoms by altering the composition of gut microbiota.