Osteoprotective Activity of Sambucus javanica Reinw Ex Blume subsp. javanica Leaf Extracts by Suppressing ROS Production

<i>Sambucus javanica</i> subsp. <i>javanica</i> (SJ) has been used in traditional medicine in the northern region of Thailand for healing bone fractures; however, studies on how this plant stimulates bone formation are still scarce. The present study aimed to investigate the potential of crude extracts and fractions obtained from SJ leaves for osteoporotic protection. All samples were investigated in murine preosteoblast MC3T3-E1 cells for bone formation and resorption biomarkers, namely alkaline phosphatase (ALP), osteocalcin (OC), osteoprotegerin (OPG), receptor activator of nuclear factor-κB ligand (RANKL), and the OPG/RANKL ratio. Additionally, calcium deposits were determined using the alizarin red S staining technique. The results indicated that the crude water and the crude ethanol extracts contained gallic acid, rutin, and chlorogenic acid as major compounds. The extracts stimulated osteoblastic cell differentiation and enhanced osteoprotective activity, as measured by a significant increase in ALP activity, OC, OPG, the OPG/RANKL ratio, and the degree of calcification. Additionally, they exhibited a negative impact on bone resorption by significantly reducing RANKL and reactive oxygen species (ROS) production. Therefore, our findings add novel evidence indicating that the SJ crude extracts from water and ethanol extraction could be further utilized as a natural active pharmaceutical ingredient (NAPI) for the development of bone health products.