METHODS: Prior to analyzing the ability of this novel combined herbal therapy to promote aspects of bone regeneration, its cytotoxicity was determined using MC3T3-E1 cells (pre-osteoblast model). Cell proliferation was evaluated using phase-contrast microscopy and cell differentiation was estimated using alkaline phosphatase activity. The effect of the combined herbal therapy (CUR + FLL) was also assessed in terms of mineralization in the extracellular matrix (ECM) of cultured cells. Further, to explore the molecular mechanisms of bone formation, time-dependent expression of bone-regulating protein biomarkers was also evaluated.
RESULTS: Combined herbal therapy (CUR + FLL) significantly upregulated the viability, proliferation and differentiation of MC3T3-E1 cells compared to the monotherapy of CUR or FLL. The magnitude of ECM mineralization (calcium deposition) was also higher in MC3T3-E1 cells treated with combined therapy. The time-dependent expression of bone-forming protein biomarkers revealed that the tendency of expression of these bone-regulating proteins was remarkably higher in cells treated with combined therapy.
CONCLUSION: The co-administration of CUR and FLL had superior promotion of elements of bone regeneration in cultured cells, thus could be a promising alternative herbal therapy for the management of bone erosive disorders such as osteoporosis.
MATERIALS AND METHODS: Murine MC3T3-E1 preosteoblastic cells were cultured in the different concentrations of AnTT (0.001-1 µg/mL) up to 24 days. Expression of osteoblastic differentiation markers was measured by qPCR (osterix [OSX], collagen 1 alpha 1 [COL1α1], alkaline phosphatase [ALP], and osteocalcin [OCN]) and by fluorometric assay for ALP activity. Detection of collagen and mineralized nodules was done via Direct Red staining and Alizarin Red staining, respectively.
RESULTS: The results showed that osteoblastic differentiation-related genes, such as OSX, COL1α1, ALP, and OCN, were significantly increased in the AnTT-treated groups compared to the vehicle group in a time-dependent manner (P<0.05). Type 1 collagen level was increased from day 3 to day 15 in the AnTT-treated groups, while ALP activity was increased from day 9 to day 21 in the AnTT-treated groups (P<0.05). Enhanced mineralization was observed in the AnTT-treated groups via increasing Alizarin Red staining from day 3 to day 21 (P<0.05).
CONCLUSION: Our results suggest that AnTT enhances the osteogenic activity by promoting the bone formation-related genes and proteins in a temporal and sequential manner.