Özhan PAZARCI, Yalkın ÇAMURCU, Seyran KILINÇ, Halef Okan DOĞAN

Does mammalian target of rapamycin or sestrin 1 protein signaling have a role in bone fracture healing?

Background/aim: Fracture healing is a complex physiological process that involves a well-orchestrated series of biological events. Themammalian target of rapamycin (mTOR) and sestrin 1 (SESN 1) play a central role in cell metabolism, proliferation, and survival. Theaim of our study is to present serum mTOR and SESN 1 levels by comparing patients with or without bone fractures. It is also a guidefor further research on the roles of these proteins in fracture healing.Materials and methods: A total of 34 patients (10 females, 24 males) with bone fractures and 32 controls (10 females, 22 males)participated in this study. After collecting serum venous blood samples, the quantitative sandwich ELISA technique was used for thedetermination of serum mTOR and SESN 1 levels.Results: The mean serum mTOR level was significantly higher in the fracture group compared to the control group (P = 0.001). However,SESN 1 levels did not significantly differ between groups (P = 0.913).Conclusion: We found that serum mTOR levels increased on the first day after fracture compared to the control group. However, weobtained no significant difference between groups in terms of SESN 1 levels. This study may guide further clinical studies investigatingthe potential role of mTOR signaling in the bone healing process.

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