Tag Archives: in vitro

Diosgenin Promotes Angiogenesis in Preosteoblast-Like Mouse Cells

Abstract

Diosgenin induces hypoxia-inducible factor-1 activation and angiogenesis through estrogen receptor-related phosphatidylinositol 3-kinase/Akt and p38 mitogen-activated protein kinase pathways in osteoblasts.

Diosgenin, extracted from the root of wild yam (Dioscorea villosa), has been reported to demonstrate an opportunity for medical application. Vascular endothelial growth factor-A (VEGF-A) plays an important role in bone-related angiogenesis, a critical process occurring during bone formation and fracture healing. In this study, we examine whether diosgenin is able to induce VEGF-A expression and to promote angiogenesis in osteoblasts. For murine MC3T3-E1 preosteoblast-like cells, VEGF-A mRNA and protein expression seemed to be significantly elevated in response to diosgenin in a concentration-dependent fashion. Conditioned media prepared from cells treated with diosgenin induced strong angiogenic activity in either in vitro or ex vivo angiogenesis assay. Furthermore, diosgenin treatment increased the stability and activity of HIF-1alpha protein. Inhibition of HIF-1alpha activity by transfection with DN-HIF-1alpha significantly diminished diosgenin-mediated VEGF-A up-regulation. The use of pharmacological inhibitors or genetic inhibition revealed that both the phosphatidylinositol 3-kinase (PI3K)/Akt and p38 signaling pathways were potentially required for diosgenin-induced HIF-1 activation and subsequent VEGF-A up-regulation. It is noteworthy that an estrogen receptor binding assay revealed that diosgenin has the strong ability to replace [(3)H]estradiol bound to estrogen receptor (IC(50), 10 nM). In addition, the specific estrogen receptor antagonists ICI 182,780 (faslodex) and tamoxifen were noted to be able to strongly inhibit diosgenin-induced, src kinase-dependent Akt and p38 MAPK activation. Taken together, such results provide evidence that diosgenin up-regulates VEGF-A and promotes angiogenesis in preosteoblast-like cells by a hypoxia-inducible factor-1alpha-dependent mechanism involving the activation of src kinase, p38 MAPK, and Akt signaling pathways via estrogen receptor.

Yen ML, Su JL, Chien CL, Tseng KW…
Mol. Pharmacol. Oct 2005
PMID: 15998873 | Free Full Text

Sophorae Fructus Inhibits Osteoclasts In Vitro

Abstract

Inhibition of IL-1beta and IL-6 in osteoblast-like cell by isoflavones extracted from Sophorae fructus.

Osteoporosis is recognized as one of the major hormonal deficiency diseases, especially in menopausal women and the elderly. When estrogen is reduced in the body, local factors such as IL-1beta and IL-6, which are known to be related with bone resorption, are increased and promote osteoclastogenesis, which is responsible for bone resorption. In the present study, we investigated whether glucosidic isoflavones (Isocal, PIII) extracted from Sophorae fructus affect the proliferation of osteoblasts and prevent osteoclastogenesis in vitro by attenuating upstream cytokines such as IL-1beta and IL-6 in a human osteoblastic cell line (MG-63) and in a primary osteoblastic culture from SD rat femurs. Interestingly, IL-1beta and IL-6 mRNA were significantly suppressed in osteoblast-like cells treated with 17beta-estradiol (E2) and PIII when compared to positive control (SDB), and this suppression was more effective at 10(-8)% than at the highest concentration of 10(-4)%. In addition, these were confirmed in protein levels using ELISA assay. In the cell line, the cells showed that E2 was the most effective in osteoblastic proliferation over the whole range of concentration (10(-4)%-10(-12)%), even though PIII also showed the second greatest effectiveness at 10(-8)%. Nitric oxide (NO) was significantly (p<0.05) upregulated in PIII and E2 over the concentration range 10(-6)% to 10(-8)% when compared to SDB, without showing any dose dependency. In bone marrow primary culture, we found by TRAP assay that PIII effectively suppressed osteoclastogenesis next to E2 in comparison with SDB and culture media (control). In conclusion, these results suggest that local bone-resorbing cytokines can be regulated by PIII at lower concentrations and that, therefore, PIII may preferentially induce anti-osteoporosis response by attenuating osteoclastic differentiation and by upregulating NO.

Joo SS, Kang HC, Lee MW, Choi YW…
Arch. Pharm. Res. Dec 2003
PMID: 14723336

Sophorae Fructus Inhibit Osteoclasts Rat Bone Cells

Abstract

Isoflavones extracted from Sophorae fructus upregulate IGF-I and TGF-beta and inhibit osteoclastogenesis in rat bone marrow cells.

Isoflavones have been a central subject in research on the natural phytoestrogens found in Leguminosae. Their effects on bone formation and remodeling are important in that they can act like estrogen by binding on estrogen receptors on the target cell surface. We, therefore, believed that isoflavones may help in the treatment of patients with estrogen deficiency disease such as estrogen replacement therapy (ERT) for osteoporosis. As commonly known, osteoporosis is one of the hormonal deficiency diseases, especially in menopausal women. When estrogen is no longer produced in the body a remarkable bone remodeling process occurs, and the associated events are regulated by growth factors in the osteoblast lineage. In the present study, we investigated whether isoflavones (Isocal) extracted from Sophorae fructus affect the growth factors IGF-I and TGF-beta that have been known to be related with bone formation. In the study, we found that the active control (PIII) effectively enhanced the level of nitric oxide (NO) and growth factors, and thereby inhibited osteoclastogenesis. The most efficient concentration was 10(-8)% within five days, whereas the comparative control (soybean isoflavone) was not as effective even at a lower concentration. In conclusion, the products which contain enriched glucosidic isoflavone and nutrient supplements such as shark cartilage and calcium can be used for osteoporosis therapy by enhancing the production of IGF-I and TGF-beta. Furthermore, the NO produced through endothelial constitutive NO synthase (ecNOS) may play a role in inhibiting bone reabsorption.

Joo SS, Won TJ, Kang HC, Lee DI
Arch. Pharm. Res. Jan 2004
PMID: 14969347

Davallic acid from Davallia Formosana Inhibits Bone Resorption in Ovariectomized Rats

Abstract

Antiosteoporotic activity of Davallia formosana.

In Taiwanese folk medicine, Davallia formosana is used to treat bone diseases, including osteoporosis. This study evaluated the anti-osteoporotic effect of ethanolic extract derived from Davallia formosana (DFE). In this in vitro study, we investigated the inhibitory action of DFE on RANKL-stimulated osteoclastogenesis. The in vivo effects of DFE on bone metabolism were evaluated using ovariectomized (OVX) rats orally administered DFE (200, 500 mg/kg), alendronate (2.5 mg/kg, three times a week) or its vehicle for 12 weeks.
This in vitro study demonstrated that DFE inhibited osteoclast differentiation, and also isolated the active component, (-)-epicatechin 3-O-β-D-allopyranoside (ECAP). DFE did not affect the body or vaginal weight in OVX rats. The bone mineral density and bone calcium content in OVX rats were lower in the control group showing that DFE was able to prevent significant bone loss. In addition, the three point bending test and the microcomputer tomography scanning showed that DFE treatment enhanced bone strength and inhibited the deterioration of trabecular microarchitecture. In the biochemical assay, DFE decreased urinary deoxypyridinoline and calcium concentrations, but did not inhibit serum alkaline phosphatase activities, indicating that it ameliorated bone loss via inhibition of bone reabsorption. These results suggest that DFE may represent a useful remedy for the treatment of bone reabsorption diseases such as osteoporosis. In addition, ECAP could be used as a marker compound to control the quality of DFE.

Ko YJ, Wu JB, Ho HY, Lin WC
J Ethnopharmacol Jan 2012
PMID: 22155390

p-Hydroxycinnamic Acid Stimulates Osteoblastogenesis Mouse Cells

Abstract

Bioactive flavonoid p-hydroxycinnamic acid stimulates osteoblastogenesis and suppresses adipogenesis in bone marrow culture.

The bioactive flavonoid p-hydroxycinnamic acid (HCA), which is an intermediate-metabolic substance in plants and fruits, is synthesized from tyrosine. The biological effect of HCA is poorly understood. Among cinnamic acid and its related compounds, HCA has a specific-anabolic effect on bone, being found to stimulate osteoblastogenesis and to inhibit osteoclastogenesis through the suppression of NF-κB signaling, thereby preventing bone loss. Bone marrow mesenchymal stem cells give rise to ostoblasts and adipocytes. HCA might therefore have effects on osteoblastogenesis and adipogenesis in bone marrow culture. This study demonstrates (1) that HCA has stimulatory effects on osteoblastogenesis and mineralization and suppressive effects on adipogenesis in mouse bone marrow culture and (2) that HCA depresses adipogenesis in mouse 3T3-L1 preadipocytes in vitro. Such effects of HCA might be involved in the differentiation of mesenchymal stem cells.

Yamaguchi M, Baile CA, Zhu S, Shoji M
Cell Tissue Res. Dec 2013
PMID: 24026435 | Free Full Text

p-Hydroxycinnamic Acid Stimulates Mineralization in Mouse Osteoblastic Cells

Abstract

Phytocomponent p-hydroxycinnamic acid stimulates mineralization in osteoblastic MC3T3-E1 cells.

Phytocomponent p-hydroxycinnamic acid (HCA) has been shown to have stimulatory effects on bone calcification and inhibitory effects on bone resorption in rat femoral tissues in vitro. Whether HCA has a stimulatory effect on mineralization in osteoblastic cells is unknown. This study was undertaken to determine the effect of HCA on mineralization in osteoblastic MC3T3-E1 cells in vitro.Cells were cultured for 72 h in a minimum essential medium (alpha-MEM) containing 10% fetal bovine serum (FBS), and the cells with subconfluency were changed to a medium containing either vehicle or HCA (10(-7)-10(-5) M) without FBS. Culture with HCA (10(-7)-10(-5) M) did not have a significant effect on cell proliferation and cell death. Deoxyribonucleic acid (DNA) content in osteoblastic cells was significantly increased after culture with HCA (10(-6) or 10(-5) M) for 48 or 72 h. Alkaline phosphatase activity in osteoblastic cells was significantly increased after culture with HCA (10(-7)-10(-5) M) for 24, 48, or 72 h. The results with Alizarin red staining for calcium showed that mineralization was significantly stimulated after culture with HCA (10(-8)-10(-5) M) for 7, 14, or 21 days. This study demonstrates that HCA has stimulatory effects on mineralization in osteoblastic MC3T3-E1 cells.

Yamaguchi M, Lai YL, Uchiyama S, Nakagawa T
Int. J. Mol. Med. Sep 2008
PMID: 18698486

p-Hydroxycinnamic Acid Inhibits Osteoclast-Like Mouse Cells

Abstract

Phytocomponent p-hydroxycinnamic acid inhibits osteoclast-like cell formation in mouse bone marrow cultures.

The phytocomponent p-hydroxycinnamic acid (HCA) has been shown to have inhibitory effects on bone-resorbing factor-stimulated bone resorption in rat femoral tissues in vitro. The effects of HCA on osteoclast-like cell formation in mouse bone marrow cultures in vitro were investigated. The bone marrow cells were cultured for 7 days in alpha-minimal essential medium containing a bone-resorbing agent [parathyroid hormone (1-34)] (PTH), prostaglandin E2 (PGE2), or tumor necrosis factor-alpha (TNF-alpha) in effective concentrations. Osteoclast-like cell formation was estimated by staining for tartrate-resistant acid phosphatase, a marker enzyme of osteoclasts. The presence of PTH (10(-7) M), PGE2 (10(-5) M), or TNF-alpha (10 ng/ml) induced a remarkable increase in osteoclast-like multinucleated cells. These increases were significantly inhibited in the presence of HCA (10(-8)-10(-5) M). HCA (10(-6) or 10(-5) M) significantly inhibited osteoclast-like cell formation induced by dibutyryl cyclic adenosine monophosphate (10(-5) M) or phorbol 12-myristate 13-acetate (10(-6) M), an activator of protein kinase C. Also, HCA (10(-8)-10(-5) M) had a significant inhibitory effect on osteoclast-like cell formation induced by the receptor activator of NF-kappaB ligand (RANKL) (10 ng/ml) in the presence of macrophage colony-stimulating factor (M-CSF) (10 ng/ml). The inhibitory effect of HCA (10(-6) or 10(-5) M) on RANKL plus M-CSF-induced osteoclast-like cell formation was not observed in the presence of cycloheximide (10(-7) M), an inhibitor of protein synthesis in the transcriptional process, or 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (10(-6) M), an inhibitor of transcription. This study demonstrates that HCA has a potent inhibitory effect on osteoclast-like cell formation in mouse bone marrow cultures. The inhibitory action of HCA may partly involve a newly synthesized protein component which is related to RANKL stimulation in osteoclastogenesis.

Lai YL, Yamaguchi M
Int. J. Mol. Med. Jan 2007
PMID: 17143556

p-Hydroxycinnamic Acid Anabolic and Antiresorptive in Rats

Abstract

Phytocomponent p-hydroxycinnamic acid stimulates bone formation and inhibits bone resorption in rat femoral tissues in vitro.

The effect of cinnamic acid or its related compounds, which is present in many plants, on bone metabolism has not been clarified yet. The effect of cinnamic acid, p-hydroxycinnamic acid (HCA), ferulic acid, caffeic acid, or 3,4-dimethoxycinnamic acid (DCA) on bone calcium content in vitro was investigated. Rat femoral-diaphyseal (cortical bone) and -metaphyseal (trabecular bone) tissues were cultured for 48,h in Dulbecco’s modified Eagle’s medium (high glucose, 4.5%) supplemented with antibiotics and bovine serum albumin. The presence of HCA (10(-5) or 10(-4),M) caused a significant increase in calcium content in the diaphyseal or metaphyseal tissues. Such an effect was not observed in the presence of cinnamic acid or other compounds at the concentration of 10(-5) or 10(-4),M. Alkaline phosphatase activity and deoxyribonucleic acid (DNA) content in the diaphyseal or metaphyseal tissues was significantly increased in the presence of HCA (10(-5) or 10(-4),M). The effect of HCA (10(-4),M) in increasing calcium content, alkaline phosphatase activity, and DNA content in the diaphyseal or metaphyseal tissues was completely prevented in the presence of cycloheximide (10(-6),M), an inhibitor of protein synthesis. Thus HCA had anabolic effects on bone components. The presence of parathyroid hormone (PTH; 10(-7),M), a bone-resorbing factor, caused a significant decrease in calcium content and a corresponding elevation in medium glucose consumption, lactic acid production or tartrate-resistant acid phosphatase (TRACP) activity in the diaphyseal or metaphyseal tissues. These alterations were completely prevented in the presence of HCA (10(-5) or 10(-4),M). This study demonstrates that p-hydroxycinnamic acid (HCA) has stimulatory effects on bone formation and inhibitory effects on bone resorption in tissue culture in vitro.

Lai YL, Yamaguchi M
Mol. Cell. Biochem. Nov 2006
PMID: 17036165

p-Hydroxycinnamic Promotes Osteoblasts by Blocking NF-κB in Mouse Cells

Abstract

The bone anabolic carotenoid p-hydroxycinnamic acid promotes osteoblast mineralization and suppresses osteoclast differentiation by antagonizing NF-κB activation.

Numerous plant derived nutritional factors including p-hydroxycinnamic acid (HCA), a member of the carotenoid family, have long been held to possess bone protective properties. Studies in animals have provided a mechanistic basis for these observations by demonstrating the capacity of HCA to promote bone formation and suppress bone resorption in vivo. However, the molecular mechanism by which HCA achieves these effects remains unclear. We have demonstrated that a centralized mechanism by which several other nutritional factors achieve similar effects is through modulation of the nuclear factor-κB (NF-κB) signal transduction pathway. NF-κB activation is essential for osteoclast formation and resorption but potently antagonizes osteoblast differentiation and mineralization. In this study we demonstrate that HCA does indeed antagonize the activation of NF-κB by the key osteoclastogenic cytokine receptor activator of NF-κB (RANKL) in RAW264.7 osteoclast precursors, suppressing their differentiation into osteoclasts. Furthermore, HCA augmented the in vitro differentiation of MC3T3 preosteoblastic cells into mineralizing osteoblasts and relieved the inhibitory action of tumor necrosis factor-α (TNF-α)-induced NF-κB signaling on transforming growth factor-β (TGF-β)- or bone morphogenetic protein-2 (BMP-2)-induced Smad activation, an important pathway in osteoblast commitment and differentiation. Our data provide a mechanism to explain the dual pro-anabolic and anti-catabolic activities of HCA.

Yamaguchi M, Weitzmann MN
Int. J. Mol. Med. Sep 2012
PMID: 22751682

Tetracyclines Prevent Bone Loss Induced by Inflammation

Abstract

Tetracyclines convert the osteoclastic-differentiation pathway of progenitor cells to produce dendritic cell-like cells.

Tetracyclines, such as doxycycline and minocycline, are used to suppress the growth of bacteria in patients with inflammatory diseases. Tetracyclines have been shown to prevent bone loss, but the mechanism involved is unknown. Osteoclasts and dendritic cells (DCs) are derived from common progenitors, such as bone marrow-derived macrophages (BMMs). In this article, we show that tetracyclines convert the differentiation pathway, resulting in DC-like cells not osteoclasts. Doxycycline and minocycline inhibited the receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis of BMMs, but they had no effects on cell growth and phagocytic activity. They influenced neither the proliferation nor the differentiation of bone-forming osteoblasts. Surprisingly, doxycycline and minocycline induced the expression of DC markers, CD11c and CD86, in BMMs in the presence of RANKL. STAT5 is involved in DC differentiation induced by GM-CSF. Midostaurin, a STAT5-signaling inhibitor, and an anti-GM-CSF-neutralizing Ab suppressed the differentiation induced by GM-CSF but not by tetracyclines. In vivo, the injection of tetracyclines into RANKL-injected mice and RANKL-transgenic mice suppressed RANKL-induced osteoclastogenesis and promoted the concomitant appearance of CD11c(+) cells. These results suggested that tetracyclines prevent bone loss induced by local inflammation, including rheumatoid arthritis and periodontitis, through osteoclast-DC-like cell conversion.

Kinugawa S, Koide M, Kobayashi Y, Mizoguchi T…
J. Immunol. Feb 2012
PMID: 22250082 | Free Full Text