Bergapten prevents lipopolysaccharide mediated osteoclast formation, bone resorption and osteoclast survival

Abstract

Purpose This study was designed to investigate the potential effect of bergapten on lipopolysaccharide (LPS)-mediated osteoclast formation, bone resorption and osteoclast survival in vitro. Methods After osteoclast precursor RAW264.7 cells were treated with bergapten (5, 20, 40 μmol/L) for 72 hours in the presence of LPS (100 ng/ml), osteoclastogenesis was identified by tartrate-resistant acid phosphatase (TRAP) staining, and the number of TRAP-positive multinucleated cells [TRAP(+ )MNCs] per well were counted. To investigate the effect of bergapten on osteoclastic bone resorption, RAW264.7 cells were treated with bergapten for six days in the presence of LPS, and the area of bone resorption was analyzed with Image Pro-Plus. Next, we examined apoptosis of RAW264.7 cells after bergapten incubation for 48 hours by flow cytometer using annexin V/propidium iodide (PI) double labeling. Finally, osteoclast survival was observed by Hoechst 33342 labeling and Western blotting after bergapten treatment for 24 hours. Results Data showed that bergapten (5-40 μmol/L) dosedependently inhibited LPS-induced osteoclast formation and bone resorption. Treatment with bergapten triggered apoptotic death of osteoclast precursor RAW264.7 cells in a dosedependent manner. Furthermore, bergapten significantly reduced the survival of mature osteoclast, as demonstrated by emergence of apoptotic nuclei and activation of apoptotic protein caspase 3/9.Conclusions These findings suggest that bergapten effectively prevents LPS-induced osteoclastogenesis, bone resorption and survival via apoptotic response of osteoclasts and their precursors. The study identifies bergapten as an inhibitor of osteoclast formation and bone resorption and provides evidence that bergapten might be beneficial as an alternative for prevention and treatment of inflammatory bone loss.

Bergapten exerts inhibitory effects on diabetes-related osteoporosis via the regulation of the PI3K/AKT, JNK/MAPK and NF-κB signaling pathways in osteoprotegerin knockout mice

“…Bergapten (BP; C 12 H 8 O 4 ), a natural anti-inflammatory and anti-tumor agent isolated from bergamot essential oil, other citrus essential oils and grapefruit juice, has been used to prevent lipopolysaccharide (LPS)-mediated osteoclast formation, bone resorption and osteoclast survival in vitro (19). Bergapten has also been shown to significantly inhibit the production of pro-inflammatory cytokines (20).…”

Bergapten promotes bone marrow stromal cell differentiation into osteoblasts in vitro and in vivo

“…BP is a natural coumarin found in many plants such as grasses, orchids, citrus fruits, and legumes. The effect of BP on bacteria-induced inflammatory bone loss has already been reported [15]. Moreover, it can enhance bone formation by osteoblasts in vitro and in vivo [16,32], suggesting that BP has the potential to prevent or treat osteoporosis by promoting the osteogenic differentiation of BMSCs.…”

“…1a), a coumarin found in many medicinal plants, has been used for decades in combination with UV radiation in skin photochemotherapy [8]. It also has many other biological functions, including anti-cancer [9][10][11], anti-oxidative [12,13], anti-inflammatory [14], and anti-resorptive effects [15]. Recently, researchers reported that BP stimulates the activity of rat primary osteoblasts and enhances bone morphogenetic protein-2 expression and bone formation via the p38 and extracellular signal regulated kinase-dependent pathway [16].…”

Bergapten alleviates osteoarthritis by regulating the ANP32A/ATM signaling pathway

“…Besides, BG has been proven to suppress inflammation by inhibiting the recruitment of neutrophils and macrophages in a tail-cutting-induced zebrafish injury site and reducing reactive oxygen species and nitric oxide generation [15]. Furthermore, Zheng et al [16] found that BG inhibited osteoclastogenesis and bone resorption stimulated by LPS, which suggests BG could be taken as a possible treatment of inflammatory bone-destructive diseases. Thus, BG may be a potential candidate for OA therapy.…”