Edgeworthia papyrifera Regulates Osteoblast and Osteoclast Differentiation In Vitro and Exhibits Anti-osteoporosis Activity in Animal Models of Osteoporosis

Planta Medica ◽  
2019 ◽  
Vol 85 (09/10) ◽  
pp. 766-773 ◽  
Author(s):  
Pansoo Kim ◽  
Yeon-Ju Nam ◽  
Woo Jung Kim ◽  
Jin Kyu Kim ◽  
Gyeongbeen Lee ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Animal Models ◽  
Osteoclast Differentiation ◽  
Raw 264.7 Cells ◽  
Tartrate Resistant Acid Phosphatase ◽  
Raw 264.7 ◽  
Treatment Of Osteoporosis ◽  
Increased Risk ◽  
Interesting Candidate

AbstractOsteoporosis is a clinical condition characterized by low bone strength that leads to an increased risk of fracture. Strategies for the treatment of osteoporosis involve inhibition of bone resorption by osteoclasts and an increase of bone formation by osteoblasts. Here, we identified the extract derived from the stem part of Edgeworthia papyrifera that enhanced differentiation of MC3T3-E1 cells to osteoblast-like cells and inhibited osteoclast differentiation of RAW 264.7 cells in vitro. In support of our observation, rutin and daphnoretin, which were previously reported to inhibit osteoclast differentiation, were identified in E. papyrifera extract. In an animal model of osteoporosis, the ovariectomy-induced increases in bone resorption biomarkers such as pyridinoline and tartrate-resistant acid phosphatase were significantly reduced by E. papyrifera extract administration at 25.6 and 48.1%, respectively. Furthermore, the ovariectomy-induced bone loss in animal models of osteoporosis was significantly prevented by the administration of E. papyrifera in our study. Taking these observations into account, we suggest that E. papyrifera is an interesting candidate for further exploration as an anti-osteoporotic agent.

scholarly journals DIHYDROTESTOSTERONE DOWNREGULATES BONE RESORPTION ACTIVITY OF OSTEOCLASTS IN DOSE DEPENDENT MANNER: AN IN VITRO MODEL USING RAW 264.7 CELLS

2017 ◽  
Vol 9 (10) ◽  
pp. 86
Author(s):  
Hnin Ei Thu ◽  
Zahid Hussain ◽  
Isa Naina Mohamed ◽  
Ahmad Nazrun Shuid
Keyword(s):  
Bone Resorption ◽  
Cathepsin K ◽  
Raw 264.7 Cells ◽  
Tartrate Resistant Acid Phosphatase ◽  
Raw 264.7 ◽  
Dependent Manner ◽  
Sod Activity ◽  
Osteoclastic Differentiation ◽  
Dose Dependent

Objective: Numerous studies have evidenced the bone regulatory potential of dihydrotestosterone in androgen-deficient osteoporosis. The present study was thus aimed to explore the translational mechanism of dihydrotestosterone to down-regulate the bone resorption activity of osteoclasts using RAW 264.7 cells as in vitro model.Methods: Prior to analyze the efficacy of dihydrotestosterone (5α-DHT) to alleviate osteoclastic differentiation, their cell viability and cell proliferative ability was assessed using lactate dehydrogenase (LDH) and MTS assays. The osteoclastic differentiation capacity of dihydrotestosterone was evaluated by measuring TRAP activity and the expression of bone resorption-related proteins such as matrix metallopeptidase-9 (MMP-9), cathepsin-K, tartrate-resistant acid phosphatase (TRAP) and NFATc1. Moreover, the effects of dihydrotestosterone were also evaluated on superoxide (free radicals) generation and superoxide dismutase (SOD) activity in RANKL-induced osteoclasts.Results: Dihydrotestosterone showed no toxicity towards RAW 264.7 cells and significantly enhanced their proliferation and growth rates in a dose-dependent fashion. It was also observed that dihydrotestosterone exhibits a remarkable inhibitory effect on differentiation, maturation and activation of osteoclasts. The marked inhibition of differentiation and activation of osteoclasts caused by 5α-DHT was due to down-regulation of the expression of MMP-9, cathepsin-K, TRAP, NFATc1, generation of superoxide and up-regulation of SOD activity in the RAW 264.7 cells.Conclusion: Resulting data provided substantially in vitroevidence for the pronounced anti-osteoclastogenetic activity of dihydrotestosterone and its therapeutic value in treating osteoporosis and other bone-erosive disorders. 

scholarly journals Inactivation of autophagy ameliorates glucocorticoid-induced and ovariectomy-induced bone loss

2015 ◽  
Vol 75 (6) ◽  
pp. 1203-1210 ◽  
Author(s):  
Neng-Yu Lin ◽  
Chih-Wei Chen ◽  
Rosebeth Kagwiria ◽  
Ruifang Liang ◽  
Christian Beyer ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Bone Loss ◽  
Osteoblast Differentiation ◽  
Osteoclast Differentiation ◽  
Cathepsin K ◽  
Tartrate Resistant Acid Phosphatase ◽  
Differentiation Markers ◽  
Treatment Of Osteoporosis ◽  
The Impact

ObjectivesAutophagy has recently been shown to regulate osteoclast activity and osteoclast differentiation. Here, we aim to investigate the impact of autophagy inhibition as a potential therapeutic approach for the treatment of osteoporosis in preclinical models.MethodsSystemic bone loss was induced in mice by glucocorticoids and by ovariectomy (OVX). Autophagy was targeted by conditional inactivation of autophagy-related gene 7 (Atg7) and by treatment with chloroquine (CQ). Bone density was evaluated by microCT. The role of autophagy on osteoclastogenesis was analysed by osteoclastogenesis and bone resorption assays. The quantification of receptor activator of nuclear factor κ B ligand and osteoprotegerin proteins in cocultures was performed using ELISA whereas that of osteoclast and osteoblast differentiation markers was by qPCR.ResultsSelective deletion of Atg7 in monocytes from Atg7fl/fl_x_LysM-Cre mice mitigated glucocorticoid-induced and OVX-induced osteoclast differentiation and bone loss compared with Atg7fl/fl littermates. Pharmacological inhibition of autophagy by treatment with CQ suppressed glucocorticoid-induced osteoclastogenesis and protected mice from bone loss. Similarly, inactivation of autophagy shielded mice from OVX-induced bone loss. Inhibition of autophagy led to decreased osteoclast differentiation with lower expression of osteoclast markers such as NFATc1, tartrate-resistant acid phosphatase, OSCAR and cathepsin K and attenuated bone resorption in vitro. In contrast, osteoblast differentiation was not affected by inhibition of autophagy.ConclusionsPharmacological or genetic inactivation of autophagy ameliorated glucocorticoid-induced and OVX-induced bone loss by inhibiting osteoclastogenesis. These findings may have direct translational implications for the treatment of osteoporosis, since inhibitors of autophagy such as CQ are already in clinical use.

scholarly journals Crataegus pinnatifida Bunge Inhibits RANKL-Induced Osteoclast Differentiation in RAW 264.7 Cells and Prevents Bone Loss in an Ovariectomized Rat Model

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Minsun Kim ◽  
MinBeom Kim ◽  
Jae-Hyun Kim ◽  
SooYeon Hong ◽  
Dong Hee Kim ◽  
...  
Keyword(s):  
Bone Loss ◽  
Rat Model ◽  
Osteoclast Differentiation ◽  
Ovariectomized Rat ◽  
Raw 264.7 Cells ◽  
Raw 264.7 ◽  
Mineral Density ◽  
Crataegus Pinnatifida

Osteoporosis is characterized by a decrease in bone microarchitecture with an increased risk of fracture. Long-term use of primary treatments, such as bisphosphonates and selective estrogen receptor modulators, results in various side effects. Therefore, it is necessary to develop alternative therapeutics derived from natural products. Crataegus pinnatifida Bunge (CPB) is a dried fruit used to treat diet-induced indigestion, loss of appetite, and diarrhea. However, research into the effects of CPB on osteoclast differentiation and osteoporosis is still limited. In vitro experiments were conducted to examine the effects of CPB on RANKL-induced osteoclast differentiation in RAW 264.7 cells. Moreover, we investigated the effects of CPB on bone loss in the femoral head in an ovariectomized rat model using microcomputed tomography. In vitro, tartrate-resistant acid phosphatase (TRAP) staining results showed the number of TRAP-positive cells, and TRAP activity significantly decreased following CPB treatment. CPB also significantly decreased pit formation. Furthermore, CPB inhibited osteoclast differentiation by suppressing NFATc1, and c-Fos expression. Moreover, CPB treatment inhibited osteoclast-related genes, such as Nfatc1, Ca2, Acp5, mmp9, CtsK, Oscar, and Atp6v0d2. In vivo, bone mineral density and structure model index were improved by administration of CPB. In conclusion, CPB prevented osteoclast differentiation in vitro and prevented bone loss in vivo. Therefore, CPB could be a potential alternative medicine for bone diseases, such as osteoporosis.

scholarly journals Effects of Isoliquiritigenin on Bone Metabolism and Uterus in Ovariectomized Rats

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 469-469
Author(s):  
Lara Sattgast ◽  
Carmen Wong ◽  
Daniel Doerge ◽  
William Helferich ◽  
Urszula Iwaniec ◽  
...  
Keyword(s):  
Gene Expression ◽  
Bone Resorption ◽  
Epithelial Cell ◽  
Osteoclast Differentiation ◽  
Ovariectomized Rats ◽  
Tartrate Resistant Acid Phosphatase ◽  
Uterine Weight ◽  
Uterine Epithelial Cell ◽  
Ovx Rats

Abstract Objectives Isoliquiritigenin (ILQ) is a phenolic compound found in licorice and is a popular dietary supplement. ILQ exhibits model-specific antioxidant, anti-inflammatory, anti-tumor, and estrogenic activities. Limited data suggest the potential of ILQ to prevent or treat osteoporosis. Therefore, this study evaluated the effects of short-duration treatment with ILQ on bone and uterine tissue in estrogen-deplete ovariectomized (ovx) rats. The uterus was important to evaluate because ILQ stimulates proliferation of MCF7 breast cancer cells through an estrogen receptor-dependent mechanism. Methods Six-week-old rats (ovx'd at 4 weeks of age) were fed diets containing 0, 100, 250 or 750 ppm ILQ (n = 5/treatment) for 1 week and sacrificed. Gene expression in femur and uterus, blood markers of global bone turnover, body composition, and uterine weight and epithelial cell height were determined. In addition, the effect of ILQ on in vitro differentiation of osteoclasts derived from bone marrow was assessed. Results Treatment resulted in a dose-dependent increase in serum ILQ with levels reaching 2.4 ± 0.2 mM in rats receiving the highest dose. ILQ did not alter serum levels of osteocalcin, a global marker of bone formation, or osteocalcin gene expression in femur. Additionally, there was little or no effect of ILQ on genes related to osteoblast differentiation or activity in femur. These largely null findings contrast with a reduction in serum CTX, a global marker of bone resorption, at all dose levels of ILQ. At the gene level, ILQ resulted in lower mRNA for genes related to osteoclast differentiation and function in femur, including Acp5 (tartrate resistant acid phosphatase), Timp2 and Mmp2, and suppressed osteoclast differentiation in vitro. ILQ had no effect on the ovx-induced increase in body weight. Ovx resulted in lower uterine weight. Treatment with ILQ at 750 ppm resulted in development of severe uterine epithelial cell hyperplasia in two of five animals. Conclusions ILQ supplementation led to reduced biochemical and gene expression markers of bone resorption in vivo and reduced osteoclast differentiation in vitro without increasing estrogen-dependent gene expression. However, the potential benefits must be weighed against potential detrimental off-target effects, including uterine hypertrophy. Funding Sources NIH [P50AT006268].

scholarly journals Inhibitory Effects of N-[2-(4-acetyl-1-piperazinyl) phenyl]-2-(2-chlorophenoxy) acetamide on Osteoclast Differentiation In Vitro via the Downregulation of TRAF6

2019 ◽  
Vol 20 (20) ◽  
pp. 5196 ◽  
Author(s):  
Zhihao Chen ◽  
Eunjin Cho ◽  
Jinkyung Lee ◽  
Sunwoo Lee ◽  
Tae-Hoon Lee
Keyword(s):  
Bone Resorption ◽  
Mononuclear Cells ◽  
Osteoclast Differentiation ◽  
Bone Diseases ◽  
Marker Genes ◽  
Tartrate Resistant Acid Phosphatase ◽  
Specific Marker ◽  
Potential Candidate ◽  
Dependent Manner

Osteoclasts are poly-nuclear cells that resorb mineral components from old or damaged bone tissue. Primary mononuclear cells are activated by receptor activator of nuclear factor kappa-Β ligand (RANKL) and differentiate into large multinucleated cells. Dysregulation of osteoclast differentiation can lead to pathological bone loss and destruction. Many studies have focused on the development of new molecules to regulate RANKL-mediated signaling. In this study, N-[2-(4-acetyl-1-piperazinyl)phenyl]-2-(2-chlorophenoxy) acetamide (PPOA-N-Ac-2-Cl) led to a significant decrease in the formation of multinucleated tartrate-resistant acid phosphatase (TRAP)-positive cells in a dose-dependent manner, without inducing significant cytotoxicity. PPOA-N-Ac-2-Cl affected the expression of osteoclast-specific marker genes, such as TRAF6, c-fos, DC-STAMP, NFATc1, MMP9, CtsK, and TRAP (Acp5), during RANKL-mediated osteoclastogenesis. Moreover, PPOA-N-Ac-2-Cl significantly attenuated the protein levels of CtsK, a critical protease involved in bone resorption. Accordingly, bone resorption activity and F-actin ring formation decreased in the presence of PPOA-N-Ac-2-Cl. In conclusion, this study shows that PPOA-N-Ac-2-Cl acts as an inhibitor of osteoclast differentiation and may serve as a potential candidate agent for the treatment of osteoclast-related bone diseases by virtue of attenuating bone resorption.

scholarly journals Psoralen and Bakuchiol Ameliorate M-CSF Plus RANKL-Induced Osteoclast Differentiation and Bone Resorption Via Inhibition of AKT and AP-1 Pathways in Vitro

2018 ◽  
Vol 48 (5) ◽  
pp. 2123-2133 ◽  
Author(s):  
Lijuan Chai ◽  
Kun Zhou ◽  
Shaoxia Wang ◽  
Han Zhang ◽  
Na Fan ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Bone Resorption ◽  
Nuclear Translocation ◽  
Osteoclast Differentiation ◽  
Gelatin Zymography ◽  
Blue Staining ◽  
Tartrate Resistant Acid Phosphatase ◽  
Phosphorylated Akt ◽  
Primary Mouse

Background/Aims: Psoralen and bakuchiol are the main active compounds found in the traditional Chinese medicine Psoralea corylifolia L., and have been used to treat osteoporosis. This study aims to investigate the anti-osteoporosis effects of these two compounds using osteoclasts precursor differentiation and bone absorption assays in vitro. Methods: Primary mouse osteoclasts precursor cells were induced by M-CSF (macrophage colony stimulating factor) plus RANKL (receptor activator of nuclear factor kappa-B ligand) in vitro. TRACP (tartrate-resistant acid phosphatase) enzyme activity and toluidine blue staining were used to observe the effects of psoralen and bakuchiol on osteoclast differentiation and bone resorption, respectively. Gelatin zymography was used to assess MMP (matrix metalloproteinase) activity, and ELISA was performed to measure cathepsin K activity. Western blotting analysis for expression of phosphorylated AKT, ERK, NF-kB, and c-jun; and immunofluorescence analysis for c-jun and p65 nuclear translocation in induced osteoclasts were then used to determine the mechanism of anti-bone resorption of psoralen and bakuchiol. Results: Mature osteoclasts were induced by M-CSF plus RANKL from primary bone marrow macrophages in vitro. Both psoralen and bakuchiol significantly inhibited TRACP enzyme activity and slightly decreased the number of TRACP+ multinuclear osteoclasts induced by M-CSF plus RANKL. Bakuchiol significantly decreased bone lacunae area and attenuated MMP-2 activity induced by M-CSF plus RANKL in osteoclasts. Both psoralen and bakuchiol significantly decreased the expression and nuclear translocation of phosphorylated c-jun stimulated by M-CSF plus RANKL, but no significant effect on p65 translocation was observed in osteoclasts. Additionally, bakuchiol significantly attenuated the increased of M-CSF plus RANKL-induced phosphorylation of AKT in osteoclasts. Conclusions: Psoralen and bakuchiol ameliorated M-CSF plus RANKL-induced osteoclast differentiation and bone resorption via inhibition of AKT and AP-1 pathways activation in vitro.

scholarly journals Aesculetin Inhibits Bone Resorption Through Down-Regulating Differentiation and Lysosomal Formation in Osteoclasts

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 442-442
Author(s):  
WooJin Na ◽  
Young-Hee Kang
Keyword(s):  
Bone Resorption ◽  
Osteoclast Differentiation ◽  
Cathepsin K ◽  
Small Gtpase ◽  
Raw 264.7 Cells ◽  
Treatment Of Osteoporosis ◽  
Funding Sources ◽  
Lysosome Biogenesis ◽  
Cellular Expression ◽  
Secretory Lysosome

Abstract Objectives For the optimal resorption of mineralized bone extracellular matrix, osteoclasts require the generation of a resorption lacuna characterized by the presence of specific proteases and a low pH. Thus, bone resorption by osteoclasts highly rely on lysosomes, the organelles specialized in intra- and extracellular material degradation. Aesculetin, a derivative of coumarin, possesses anti-inflammatory and anti-bacterial effects. The purpose of this study was to identify that aesculetin inhibited osteoclast differentiation and bone resorption through down-regulating lysosomal formation. Methods Raw 264.7 cells were cultured for 5 days on α-MEM with 10% FBS in the absence or presence of 50 ng/ml RANKL and 1–10 μM aesculetin. Tartrate-resistance acid phosphatase (TRAP) staining and bone resorption assay were performed by using assay kits. Western blotting was conducted with antibodies of target proteins involved in activation and lysosome biogenesis of osteoclasts. Immunocytochemical analysis employed LysoTracker for lysosome staining and α-tubulin antibody conjugated with FITC. Results Aesculetin inhibited RANKL-treated formation of multinucleated osteoclasts with a reduction of TRAP activity. When 1–10 μM aesculetin was treated to RANKL-exposed osteoclasts, the bone resorption was highly suppressed in osteoclasts. In addition, aesculetin reduced cellular expression of carbonic anhydrase II, vacuolar-type H (+)-ATPase D2 and cathepsin K elevated by RANKL, all involved in the bone resorption. Furthermore, aesculetin curtailed cellular induction of autophagy-related (Atg)5, Atg7 and small GTPase Rab7 elevated by RANKL for lysosome transportation/secretion and bone resorption in osteoclasts. Conclusions Aesculetin was effective in retarding osteoclast differentiation and secretory lysosome formation for osteoclast resorption, indicating that this compound may be a potential agent for the treatment of osteoporosis. Funding Sources No funding sources to report.

scholarly journals Protective Effects of Fermented Oyster Extract against RANKL-Induced Osteoclastogenesis through Scavenging ROS Generation in RAW 264.7 Cells

2019 ◽  
Vol 20 (6) ◽  
pp. 1439 ◽  
Author(s):  
Jin-Woo Jeong ◽  
Sung Choi ◽  
Min Han ◽  
Gi-Young Kim ◽  
Cheol Park ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Osteoclast Differentiation ◽  
Bone Diseases ◽  
Raw 264.7 Cells ◽  
Ros Generation ◽  
Tartrate Resistant Acid Phosphatase ◽  
Raw 264.7 ◽  
Nuclear Factor ◽  
Protective Effects ◽  
Induced Expression

Excessive bone resorption by osteoclasts causes bone loss-related diseases and reactive oxygen species (ROS) act as second messengers in intercellular signaling pathways during osteoclast differentiation. In this study, we explored the protective effects of fermented oyster extract (FO) against receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-induced osteoclast differentiation in murine monocyte/macrophage RAW 264.7 cells. Our results showed that FO markedly inhibited RANKL-induced activation of tartrate-resistant acid phosphatase and formation of F-actin ring structure. Mechanistically, FO has been shown to down-regulate RANKL-induced expression of osteoclast-specific markers by blocking the nuclear translocation of NF-κB and the transcriptional activation of nuclear factor of activated T cells c1 (NFATc1) and c-Fos. Furthermore, FO markedly diminished ROS production by RANKL stimulation, which was associated with blocking the expression of nicotinamide adenine dinucleotide phosphate oxidase 1 (NOX1) and its regulatory subunit Rac-1. However, a small interfering RNA (siRNA) targeting NOX1 suppressed RANKL-induced expression of osteoclast-specific markers and production of ROS and attenuated osteoclast differentiation as in the FO treatment group. Collectively, our findings suggest that FO has anti-osteoclastogenic potential by inactivating the NF-κB-mediated NFATc1 and c-Fos signaling pathways and inhibiting ROS generation, followed by suppression of osteoclast-specific genes. Although further studies are needed to demonstrate efficacy in in vivo animal models, FO may be used as an effective alternative agent for the prevention and treatment of osteoclastogenic bone diseases.

scholarly journals Synovial Fibroblasts Infected with Salmonella enterica Serovar Typhimurium Mediate Osteoclast Differentiation and Activation

2004 ◽  
Vol 72 (12) ◽  
pp. 7183-7189 ◽  
Author(s):  
Xiang Zhang ◽  
Jane E. Aubin ◽  
Tae-Hwan Kim ◽  
Ursula Payne ◽  
Basil Chiu ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Salmonella Enterica ◽  
Bone Structure ◽  
Osteoclast Differentiation ◽  
Synovial Fibroblasts ◽  
Joint Disease ◽  
Tartrate Resistant Acid Phosphatase ◽  
Rankl Expression ◽  
Serovar Typhimurium

ABSTRACT The mechanisms whereby arthritogenic organisms may induce cartilage and bone erosions in infection-triggered arthritis remain unknown. In this study, we asked whether an arthritogenic organism could contribute to osteoclast differentiation and activation through regulation of the receptor activator of NF-κB ligand (RANKL) in synovial fibroblasts. Rat synovial fibroblasts were infected in vitro with Salmonella enterica serovar Typhimurium and monitored over time. The expression of RANKL in resting and infected synovial fibroblasts was quantified by reverse transcription-PCR and Western blotting. Osteoclast progenitors, isolated from femurs of 8-week-old rats and cultured in the presence of macrophage colony-stimulating factor, were cocultured with either infected or noninfected synovial fibroblasts for 2 to 4 days. Differentiation and maturation of osteoclasts were determined by morphology and tartrate-resistant acid phosphatase (TRAP) staining and by a bone resorption bioassay. RANKL expression was undetectable in resting synovial fibroblasts but was dose-dependently upregulated in cells after Salmonella infection. Osteoprotegerin was constitutively expressed by synovial fibroblasts and was not upregulated by infection. Further, we observed the formation of multinucleated TRAP-positive cells and formation of bone resorption pits in cocultures of bone marrow-derived osteoclast precursors with synovial fibroblasts infected with Salmonella but not with heat-killed Salmonella or noninfected cells. Arthritogenic bacteria may alter bone structure via synovial fibroblast intermediaries, since infected synovial fibroblasts (i) upregulate RANKL expression and (ii) enhance osteoclast precursor maturation into multinucleated, TRAP-positive, bone-resorbing, osteoclast-like cells. These data provide a link between infection and osteoclastogenesis. A better understanding of infection-mediated osteoclast differentiation and activation may provide new therapeutic strategies for inflammatory joint disease.

scholarly journals The Prenyl Group Contributes to Activities of Phytoestrogen 8-Prenynaringenin in Enhancing Bone Formation and Inhibiting Bone Resorption In Vitro

Endocrinology ◽  
2013 ◽  
Vol 154 (3) ◽  
pp. 1202-1214 ◽  
Author(s):  
Lei-Guo Ming ◽  
Xiang Lv ◽  
Xiao-Ni Ma ◽  
Bao-Feng Ge ◽  
Ping Zhen ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Mrna Expression ◽  
Bone Marrow Cells ◽  
Osteoclast Differentiation ◽  
Cathepsin K ◽  
Active Role ◽  
Osteoclast Formation ◽  
Calcium Deposition ◽  
Tartrate Resistant Acid Phosphatase

Abstract Previous studies have found that 8-prenylflavonoids have a higher osteogenic activity than do flavonoids, which suggested that the 8-prenyl group may play an active role in bone-protective properties. To address this hypothesis, activities of 8-prenylnaringenin (PNG) and naringenin (NG) in osteoblast and osteoclast differentiation and function were compared in vitro. PNG was found to have a stronger ability than NG to improve osteoblast differentiation and osteogenic function in cultured rat calvarial osteoblasts, as demonstrated by levels of alkaline phosphatase activity, osteocalcin, calcium deposition, and the number and area of mineralized bone nodules, as well as mRNA expression of osteogenesis-related genes Bmp-2, OSX, and Runx-2. In addition, although expression of osteoclastogenic inducer receptor activator of nuclear factor kappa-B ligand (RANKL) was not affected, that of osteoclastogenesis inhibitor osteoprotegerin (OPG) and consequently the OPG/RANKL ratio were increased, more potently by PNG than NG. PNG was also found to have a higher potency than NG in inhibiting the osteoclast formation in rabbit bone marrow cells and their resorptive activity, as revealed by lower numbers of osteoclasts formed, lower numbers and areas of bone resorption pits, and lower mRNA expression levels of tartrate-resistant acid phosphatase and cathepsin K. Furthermore, PNG induced apoptosis of mature osteoclasts at a higher degree and at an earlier time than did NG. These results indicate that the 8-prenyl group plays an important role and contributes to the higher bone-protective activity of PNG in comparison with NG.

Sign in / Sign up

Export Citation Format

Share Document