DELE1 and hyperinsulinemic hypoglycemia, familial, 4: Finally, as DELE1 exerts a strong myoprotective effect in models of MM/CM without attenuating most ultrastructural mitochondrial defects or OXPHOS deficiency, it suggests that cellular stress response to mitochondrial dysfunction should be monitored in addition to changes to mitochondrial structure and OXPHOS in assessing potential interventions for mitochondrial disorders.