Mitochondrial Resilience: Unraveling the Triadic Interplay of Phosphocreatine, Cyclophilin D, and STAT3 in Heart Failure.

Heart failure remains a major global health burden, with mitochondrial dysfunction recognized as a key contributor to its onset and progression. This review highlights three critical regulators of mitochondrial integrity phosphocreatine (PCr), cyclophilin D (CypD), and signal transducer and activator of transcription 3 (STAT3) and their coordinated roles in cardiac function. PCr is vital for sustaining myocardial energy balance, particularly under metabolic stress. CypD controls the mitochondrial permeability transition pore, regulating cell death pathways that contribute to cardiac injury. Beyond its classical nuclear actions, STAT3 supports mitochondrial respiration, biogenesis, and resistance to oxidative damage. Evidence reveals a functional interplay among these regulators, forming a protective network that preserves mitochondrial performance. Disruption of this network promotes energetic failure, mitochondrial injury, and heart failure progression. Targeting PCr metabolism, CypD activity, and STAT3 signaling may represent a promising therapeutic approach to enhance mitochondrial resilience and improve clinical outcomes in heart failure patients.