Unraveling the Osteogenic Activity and Molecular Mechanism of an Antioxidant Collagen Peptide in MC3T3-E1 Cells.

Background: Osteoporosis has become an inevitable health issue with global aging, and the current drug treatments often have adverse side effects, highlighting the need for safer and more effective therapies. Collagen-derived peptides are promising alternatives due to their favorable safety profile and biological activity. This study aimed to investigate the osteogenic and anti-apoptotic properties of collagen peptide UU1 (GASGPMGPR) in addition to its antioxidant activity. Methods: The effects of UU1 were evaluated in MC3T3-E1 cells by assessing osteogenic markers, including alkaline phosphatase (ALP), Cyclin D1, runt-related transcription factor 2 (Runx2), and Akt/β-catenin signaling. Western blot analysis quantified collagen I, osteocalcin, and phosphorylated Akt levels. Anti-apoptotic effects were measured via p-Akt levels and the Bax/Bcl-2 ratio. Computational molecular docking was performed to explore the molecular mechanism of UU1 via its interaction with epidermal growth factor receptor (EGFR) and collagen-binding integrin. Results: UU1 treatment promoted cell differentiation, with elevated ALP, Cyclin D1, Runx2, and Akt/β-catenin signaling. Notably, at 0.025 mg/mL, UU1 upregulated the levels of collagen I, osteocalcin, and phosphorylated Akt by 2.14, 3.37, and 1.95 times, respectively, compared to the control. Additionally, UU1 exhibited anti-apoptotic effects, indicated by increased p-Akt levels and a reduced Bax/Bcl-2 ratio. Molecular docking analysis suggested that UU1 could assist the dimerization of EGFR, facilitating downstream signaling transductions and activating collagen-binding integrin. Conclusions: These findings highlight UU1 as a multifunctional peptide with antioxidant, osteogenic, and anti-apoptotic properties, positioning it as a promising candidate for anti-osteoporosis applications in the food and pharmaceutical industries.