Quinoxaline derivative of oleanolic acid inhibits osteoclastic bone resorption and prevents ovariectomy-induced bone loss

<p>Bone homeostasis is maintained through a delicate balance between osteoblastic bone formation and osteoclastic bone resorption. Bone loss is caused by decreasing in osteoblastic bone formation and increase in osteoclastic bone resorption, thereby leading to osteoporosis. Functional food factors may play a role in<br />the prevention of osteoporosis. Functional food factors including genistein, menaquinone-7 (vitamin K2) and β-cryptoxanthine have been shown to possess a potential osteogenic effect. These factors have been shown to reveal stimulatory effects on osteoblastic bone formation and suppressive effects on osteoclastic<br />bone resorption. Dietary intake of these factors has been shown to reveal preventive effects on bone loss in animal models of osteoporosis and human subjects. This review will introduce our findings concerning roles of functional food factors in regulation of bone homeostasis and prevention of osteoporosis.</p>

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A novel inhibitor of NF-κB-inducing kinase prevents bone loss by inhibiting osteoclastic bone resorption in ovariectomized mice

Bone ◽

10.1016/j.bone.2020.115316 ◽

2020 ◽

Vol 135 ◽

pp. 115316 ◽

Cited By ~ 6

Author(s):

Nana Takakura ◽

Miho Matsuda ◽

Masud Khan ◽

Fumitaka Hiura ◽

Kazuhiro Aoki ◽

...

Keyword(s):

Bone Resorption ◽

Bone Loss ◽

Osteoclastic Bone Resorption ◽

Ovariectomized Mice

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Enhancement of Osteoclastic Bone Resorption and Suppression of Osteoblastic Bone Formation in Response to Reduced Mechanical Stress Do Not Occur in the Absence of Osteopontin

Journal of Experimental Medicine ◽

10.1084/jem.193.3.399 ◽

2001 ◽

Vol 193 (3) ◽

pp. 399-404 ◽

Cited By ~ 167

Author(s):

Muneaki Ishijima ◽

Susan R. Rittling ◽

Teruhito Yamashita ◽

Kunikazu Tsuji ◽

Hisashi Kurosawa ◽

...

Keyword(s):

Bone Resorption ◽

Bone Loss ◽

Bone Formation ◽

Mechanical Stress ◽

Bone Matrix ◽

Osteoclastic Bone Resorption ◽

Tail Suspension ◽

Wild Type ◽

Osteoblastic Bone Formation

Reduced mechanical stress to bone in bedridden patients and astronauts leads to bone loss and increase in fracture risk which is one of the major medical and health issues in modern aging society and space medicine. However, no molecule involved in the mechanisms underlying this phenomenon has been identified to date. Osteopontin (OPN) is one of the major noncollagenous proteins in bone matrix, but its function in mediating physical-force effects on bone in vivo has not been known. To investigate the possible requirement for OPN in the transduction of mechanical signaling in bone metabolism in vivo, we examined the effect of unloading on the bones of OPN−/− mice using a tail suspension model. In contrast to the tail suspension–induced bone loss in wild-type mice, OPN−/− mice did not lose bone. Elevation of urinary deoxypyridinoline levels due to unloading was observed in wild-type but not in OPN−/− mice. Analysis of the mechanisms of OPN deficiency–dependent reduction in bone on the cellular basis resulted in two unexpected findings. First, osteoclasts, which were increased by unloading in wild-type mice, were not increased by tail suspension in OPN−/− mice. Second, measures of osteoblastic bone formation, which were decreased in wild-type mice by unloading, were not altered in OPN−/− mice. These observations indicate that the presence of OPN is a prerequisite for the activation of osteoclastic bone resorption and for the reduction in osteoblastic bone formation in unloaded mice. Thus, OPN is a molecule required for the bone loss induced by mechanical stress that regulates the functions of osteoblasts and osteoclasts.

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Decitabine Inhibits Bone Resorption in Periodontitis by Upregulating Anti-Inflammatory Cytokines and Suppressing Osteoclastogenesis

Biomedicines ◽

10.3390/biomedicines9020199 ◽

2021 ◽

Vol 9 (2) ◽

pp. 199

Author(s):

Urara Tanaka ◽

Shunichi Kajioka ◽

Livia S. Finoti ◽

Daniela B. Palioto ◽

Denis F. Kinane ◽

...

Keyword(s):

Dna Methylation ◽

Bone Resorption ◽

Bone Loss ◽

Inflammatory Cytokines ◽

Osteoclast Differentiation ◽

Tartrate Resistant Acid Phosphatase ◽

Dependent Manner ◽

Bone Homeostasis ◽

Osteoblastic Cell Line ◽

Anti Inflammatory

DNA methylation controls several inflammatory genes affecting bone homeostasis. Hitherto, inhibition of DNA methylation in vivo in the context of periodontitis and osteoclastogenesis has not been attempted. Ligature-induced periodontitis in C57BL/6J mice was induced by placing ligature for five days with Decitabine (5-aza-2′-deoxycytidine) (1 mg/kg/day) or vehicle treatment. We evaluated bone resorption, osteoclast differentiation by tartrate-resistant acid phosphatase (TRAP) and mRNA expression of anti-inflammatory molecules using cluster differentiation 14 positive (CD14+) monocytes from human peripheral blood. Our data showed that decitabine inhibited bone loss and osteoclast differentiation experimental periodontitis, and suppressed osteoclast CD14+ human monocytes; and conversely, that it increased bone mineralization in osteoblastic cell line MC3T3-E1 in a concentration-dependent manner. In addition to increasing IL10 (interleukin-10), TGFB (transforming growth factor beta-1) in CD14+ monocytes, decitabine upregulated KLF2 (Krüppel-like factor-2) expression. Overexpression of KLF2 protein enhanced the transcription of IL10 and TGFB. On the contrary, site-directed mutagenesis of KLF2 binding site in IL10 and TFGB abrogated luciferase activity in HEK293T cells. Decitabine reduces bone loss in a mouse model of periodontitis by inhibiting osteoclastogenesis through the upregulation of anti-inflammatory cytokines via KLF2 dependent mechanisms. DNA methyltransferase inhibitors merit further investigation as a possible novel therapy for periodontitis.

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Estrogen Decreases Cytoskeletal Organization by Forming an ERα/SHP2/c-Src Complex in Osteoclasts to Protect against Ovariectomy-Induced Bone Loss in Mice

Antioxidants ◽

10.3390/antiox10040619 ◽

2021 ◽

Vol 10 (4) ◽

pp. 619

Author(s):

Hyun-Jung Park ◽

Malihatosadat Gholam-Zadeh ◽

Sun-Young Yoon ◽

Jae-Hee Suh ◽

Hye-Seon Choi

Keyword(s):

Bone Resorption ◽

Bone Loss ◽

Ring Formation ◽

Tartrate Resistant Acid Phosphatase ◽

Actin Ring ◽

Collagen Crosslinks ◽

Trap Staining ◽

Src Activation

Loss of ovarian function is closely related to estrogen (E2) deficiency, which is responsible for increased osteoclast (OC) differentiation and activity. We aimed to investigate the action mechanism of E2 to decrease bone resorption in OCs to protect from ovariectomy (OVX)-induced bone loss in mice. In vivo, tartrate-resistant acid phosphatase (TRAP) staining in femur and serum carboxy-terminal collagen crosslinks-1 (CTX-1) were analyzed upon E2 injection after OVX in mice. In vitro, OCs were analyzed by TRAP staining, actin ring formation, carboxymethylation, determination of reactive oxygen species (ROS) level, and immunoprecipitation coupled with Western blot. In vivo and in vitro, E2 decreased OC size more dramatically than OC number and Methyl-piperidino-pyrazole hydrate dihydrochloride (MPPD), an estrogen receptor alpha (ERα) antagonist, augmented the OC size. ERα was found in plasma membranes and E2/ERα signaling affected receptor activator of nuclear factor κB ligand (RANKL)-induced actin ring formation by rapidly decreasing a proto-oncogene tyrosine-protein kinase, cellular sarcoma (c-Src) (Y416) phosphorylation in OCs. E2 exposure decreased physical interactions between NADPH oxidase 1 (NOX1) and the oxidized form of c-Src homology 2 (SH2)-containing protein tyrosine phosphatase 2 (SHP2), leading to higher levels of reduced SHP2. ERα formed a complex with the reduced form of SHP2 and c-Src to decrease c-Src activation upon E2 exposure, which blocked a signal for actin ring formation by decreased Vav guanine nucleotide exchange factor 3 (Vav3) (p–Y) and Ras-related C3 botulinum toxin substrate 1 (Rac1) (GTP) activation in OCs. E2/ERα signals consistently inhibited bone resorption in vitro. In conclusion, our study suggests that E2-binding to ERα forms a complex with SHP2/c-Src to attenuate c-Src activation that was induced upon RANKL stimulation in a non-genomic manner, resulting in an impaired actin ring formation and reducing bone resorption.

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Physiological plasma levels of androgens reduce bone loss in the ovariectomized rat

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1998.274.2.e328 ◽

1998 ◽

Vol 274 (2) ◽

pp. E328-E335 ◽

Cited By ~ 5

Author(s):

C. K. Lea ◽

A. M. Flanagan

Keyword(s):

Bone Resorption ◽

Bone Loss ◽

Protective Effect ◽

Cancellous Bone ◽

Plasma Levels ◽

Slow Release ◽

Bone Volume ◽

Ovariectomized Rat ◽

Ovx Rats ◽

Reduce Bone Loss

The effect of androstenedione (ADIONE) slow-release pellets on cancellous bone volume (BV/TV) at the tibial metaphysis was investigated in ovariectomized (OVX) rats at various times from 21 to 180 days. Plasma levels of ADIONE and testosterone (T) in OVX rats were significantly reduced at 21 days and were restored close to levels in the sham rats with the 1.5-mg ADIONE pellet. OVX animals with and without ADIONE pellets resulted in close to a 50% reduction in BV/TV by day 21. By day 180, OVX rats had only ∼5% BV/TV, whereas that in ADIONE-treated OVX rats was significantly greater at ∼12%. The reduced BV/TV was associated with increased bone resorption and formation. In a separate 90-day experiment, we found that the antiandrogen, Casodex, abrogated the ADIONE-induced skeletal-protective effect in OVX rats, whereas the antiaromatase, Arimidex, had no effect. This provides evidence that ADIONE protects against the development of osteopenia in the estrogen-deficient rat and mediates its effect through androgens and not estrogens.

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Nobiletin, a Polymethoxy Flavonoid, Suppresses Bone Resorption by Inhibiting NFκB-Dependent Prostaglandin E Synthesis in Osteoblasts and Prevents Bone Loss Due to Estrogen Deficiency

Journal of Pharmacological Sciences ◽

10.1254/jphs.10193sc ◽

2011 ◽

Vol 115 (1) ◽

pp. 89-93 ◽

Cited By ~ 30

Author(s):

Suguru Harada ◽

Tsukasa Tominari ◽

Chiho Matsumoto ◽

Michiko Hirata ◽

Morichika Takita ◽

...

Keyword(s):

Bone Resorption ◽

Bone Loss ◽

Estrogen Deficiency ◽

Prostaglandin E

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Capsaicin, a TRPV1 Ligand, Suppresses Bone Resorption by Inhibiting the Prostaglandin E Production of Osteoblasts, and Attenuates the Inflammatory Bone Loss Induced by Lipopolysaccharide

ISRN Pharmacology ◽

10.5402/2012/439860 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 11

Author(s):

Megumi Kobayashi ◽

Kenta Watanabe ◽

Satoshi Yokoyama ◽

Chiho Matsumoto ◽

Michiko Hirata ◽

...

Keyword(s):

Bone Resorption ◽

Bone Loss ◽

Transient Receptor Potential ◽

Interleukin 1 ◽

Osteoclast Differentiation ◽

Bone Diseases ◽

Prostaglandin E ◽

Transient Receptor Potential Vanilloid ◽

Cox 2

Capsaicin, a transient receptor potential vanilloid type 1 (TRPV1) ligand, regulates nerve-related pain-sensitive signals, inflammation, and cancer growth. Capsaicin suppresses interleukin-1-induced osteoclast differentiation, but its roles in bone tissues and bone diseases are not known. This study examined the effects of capsaicin on inflammatory bone resorption and prostaglandin E (PGE) production induced by lipopolysaccharide (LPS) in vitro and on bone mass in LPS-treated mice in vivo. Capsaicin suppressed osteoclast formation, bone resorption, and PGE production induced by LPS in vitro. Capsaicin suppressed the expression of cyclooxygenase-2 (COX-2) and membrane-bound PGE synthase-1 (mPGES-1) mRNAs and PGE production induced by LPS in osteoblasts. Capsaicin may suppress PGE production by inhibiting the expression of COX-2 and mPGES-1 in osteoblasts and LPS-induced bone resorption by TRPV1 signals because osteoblasts express TRPV1. LPS treatment markedly induced bone loss in the femur in mice, and capsaicin significantly restored the inflammatory bone loss induced by LPS in mice. TRPV1 ligands like capsaicin may therefore be potentially useful as clinical drugs targeting bone diseases associated with inflammatory bone resorption.

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