Mitochondrial turnover

Mitochondrial turnover is the integrated biological process of mitochondrial biogenesis and selective degradation, primarily through mitophagy, which ensures the maintenance of a healthy and functional mitochondrial network within cells [1, 12, 16]. This cycle is critical for cellular energy homeostasis and quality control, as it removes damaged or dysfunctional organelles that would otherwise accumulate and cause oxidative stress or trigger apoptosis [13, 15]. The process is predominantly regulated by the AMPK/SIRT1/PGC-1α signaling axis for biogenesis and the PINK1/Parkin pathway for mitophagy, allowing the cell to adapt its mitochondrial mass and quality to changing energy demands [3, 10, 13]. Dysregulation of mitochondrial turnover is strongly implicated in various pathologies, particularly those associated with aging and high energy demand, such as Parkinson's disease, type 2 diabetes, and cardiovascular disorders [5, 8]. Therapeutic strategies currently target specific components of this process using small molecules like metformin or resveratrol, which activate energy-sensing pathways to stimulate renewal [1, 10]. However, the therapeutic challenge lies in achieving a precise balance between degradation and synthesis, as excessive or insufficient turnover can lead to impaired metabolic function or unintended cell death [3, 11].

Other names

Mitochondrial quality controlMitochondrial homeostatic cycleMitochondrial renewalMitophagy-biogenesis cycle

Modulation of AMPK and mTOR signaling pathways, activation of Sirtuins (SIRT1), induction of PGC-1alpha/TFAM-mediated biogenesis, and promotion of PINK1/Parkin-mediated mitophagy to maintain mitochondrial quality and cellular energy homeostasis.