Chemical Characterization of the Functional Natural Products from the Fruits of Sea Buckthorn (Hippophae rhamnoides) that Control Osteoblast Differentiation

Abstract

In the screening assay, we found that the ethanolic extract of the fruits of sea buckthorn (Hippophae rhamnoides) showed anti-osteoporosis effects in vitro and in vivo. A bioassay-guided fractionation and LC/MS-based isolation of the active ethanolic extract resulted to the isolation of potential bioactive compounds (1-6), chemical structures of which were identified as four triterpenes, ursolic acid (1), uvaol (2), oleanolic aldehyde (3), and ursolic aldehyde (4) by the interpretation of their spectroscopic NMR data and LC-MS analysis as well as HR-ESI-MS data. The isolated compounds were tested for the efficacy of promoting osteoblast differentiation and the expression of mRNA biomarkers related to osteogenesis. Firstly, their effects on osteoblast differentiation of mouse mesenchymal stem cell C3H10T1/2 were tested. As a result of quantification by alkaline phosphate staining, ursolic aldehyde (4) at 10 μg/mL concentration showed 11.2 times higher activity than that of negative control, and four kinds of gene expressions were significantly increased in bone formation-related biomarker analysis. These findings provide the experimental evidence that ursolic aldehyde (4) derived from the extract of H. rhamnoides can be the active constituent for bone health. keyword : Hippophae rhamnoides, Anti-Osteoporosis, Ursolic aldehyde