PPM1K and sarcopenia: 3.Dysfunction in BCAA catabolism may be a driver of sarcopenia and is positively correlated with muscle mass and grip strength. Within this pathway, the BCKDHB and BCAT2 genes serve as potential therapeutic targets; activating BCKDH with BT2 to enhance BCAA catabolism can improve muscle mass and function, while inhibiting mTOR activation counteracts BCAA-associated skeletal muscle atrophy.