PPARGC1A and sarcopenia: Concurrently, mitochondrial biogenesis, the process of forming new mitochondria, regulated by master factors such as peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha) and mitochondrial transcription factor A (TFAM), also declines with age in sarcopenia (Alizadeh Pahlavani et al., 2022).