Metformin Administration Protects Against Deltoid Tendon Damage Through Activation of Notch Signaling

Abstract

Type 2 Diabetes Mellitus (T2DM) is a growing global health concern that is associated with severe complications including diabetic tendinopathy. In this study, we found that T2DM patients had a significantly higher prevalence of tendon surgery compared to non-T2DM patients, which were alongside impaired ECM and cell adhesion. Notably, metformin-treated T2DM patients had a lower prevalence of tendon surgery compared to other medications, along with improved tendon fiber structure, downregulation of tendon damage marker MMP3, and upregulation of HES1, a Notch signaling effector gene. Metformin also activates Notch signaling in cultured tenocytes, and tendons from diabetic mice and aged monkey. These findings highlight metformin's potential to protect tendons by activating Notch signaling, offering novel insights into its therapeutic benefits beyond glucose regulation.