Evaluation of A Folk Medicinal Plant Used in Taiwan on A Glucocorticoid-Induced Osteoporosis Zebrafish Model

Osteoporosis (OP) is a complex bone disease, one of the causes is by prolonged glucocorticoid use, increasing the risk of fractures. With growing interest in natural compounds for their safety and multifunctional properties, Dicliptera chinensis (DC) plant, traditionally used for liver disorders, shows promise due to its anti-inflammatory and antioxidant activities for OP treatment. This study aims to evaluate the potential of DC in preventing glucocorticoid-induced osteoporosis (GIOP). The effects of DC on GIOP were evaluated in zebrafish larvae to assess survival rate and mineralization activity. Whole dried DC plant (100 g) was extracted with 70°C of hot water (2 L, twice). After filtration, the liquid extract was concentrated using a vacuum rotary evaporator and lyophilized by freeze-drying, yielding 25.12 g of extract. The extract was partitioned with ethyl acetate (EA), n-butanol (BU), and ddH2O (Aq) to get fractions respectively. Among them, the DCBU fraction exhibited the strongest mineralization activity (2.20 mm, p < 0.01) compared to the induced group (1.58 mm). Further separation using Diaion HP-20 column chromatography produced six sub-fractions, among which DCBU-3 showed the highest mineralization activity (2.10 mm, p < 0.01) compared to the induced group (1.57 mm). Additionally, RT-qPCR analysis confirmed that DCBU-3 increase the expression of key genes including wnt16, axin2, and ctnnb1 in the Wnt/β-catenin signaling pathway, as well as osteoblast related gene runx2b, sp7, and ocn, indicating enhanced bone formation activity. Compound 1 (0.1 mg) was successfully isolated from the DCBU-3 fraction using HPLC and NMR techniques, and was identified as roseoside. The DC plant has a potential as natural alternatives for the treatment of GIOP. Further studies are warranted to explore the molecular mechanisms and clinical relevance of roseoside in bone health.