Table 1.

Potential markers of mitochondrial allostatic load – MAL.

Mitochondrial features	Examples	Physiological effects
Mitochondrial content	Decreased or increased mitochondrial number, mitochondrial size	Energy production capacity, metabolic regulation
Molecular damage	Oxidized mtDNA, proteins, and lipids	Multiple effects
Molecular composition	Lipid and protein composition	Multiple effects
Dynamics, morphology, and ultrastructure	Fragmented, elongated, or “donut” morphology; Reduced number or abnormal cristae	Energy production capacity, oxidative stress, apoptosis, systemic metabolic regulation
Genetic (mtDNA)	mtDNA copy number per cell, mtDNA mutations and deletions	Energy production capacity, aging, systemic metabolic regulation
Respiration and OXPHOS	ETC enzymatic activity, oxygen consumption rate, ATP synthesis	Energy production capacity, multiple functions (gene expression, endocrine, metabolic)
Other mitochondrial functions	ROS production, calcium uptake and release, decreased membrane potential, biosynthesis	Multiple functions (gene expression, endocrine, metabolic, tissue repair)
Mitokine production and metabolite signaling	ccf-mtDNA release, mtDNA-encoded proteins, Krebs cycle metabolic intermediates	Paracrine and endocrine effects on multiple organ systems