Targeting ANT1 to regulate PINK1/Parkin-mediated mitophagy is an effective treatment of trauma-induced tendon heterotopic ossification.

Background: Heterotopic ossification (HO) is a common degenerative disease following trauma. Tendon HO is primarily attributed to osteogenic differentiation of stem/progenitor cells within the tendon. However, the precise mechanism underlying this process remains unclear. Recent studies suggest that PTEN induced kinase 1 (PINK1)/Parkin-mediated mitophagy plays a crucial role in biomineralization. Adenine nucleotide translocase 1 (ANT1), an upstream regulator of the PINK1/Parkin pathway, may influence tendon ossification development by modulating mitophagy. Methods: This study investigated the role of mitophagy in tendon osteogenesis in clinical specimens, mouse tissues, and cells. The impact of ANT1 on tendon osteogenesis through mitophagy regulation was assessed by knocking down solute carrier family 25 member 4 (Slc25a4) both in vitro and in vivo. Furthermore, elamipretide was identified as a potential targeted drug for ANT1 through computer virtual screening and experimental verification. Its therapeutic efficacy on tendon ossification was validated using mouse cells, tissues, and human cells. Results: This study found that PINK1/Parkin-mediated mitophagy was activated during tendon ossification, and the regulation of mitophagy could impact the osteogenesis of injured tendon-derived progenitor cells (inTPCs). Loss of Slc25a4 inhibited tendon ossification by downregulating the excessive mitophagy. Elamipretide, a targeted drug for ANT1, showed significant efficacy in treating HO. Conclusion: Modulating PINK1/Parkin-mediated mitophagy by targeting ANT1 mitigated the progression of trauma-induced tendon HO, indicating ANT1 can be a potential therapeutic target for HO, with elamipretide emerging as a promising drug for its treatment. The translational potential of this article: This study identifies ANT1 as a therapeutic target and supports elamipretide as a promising treatment strategy for HO.