Inhibition of receptor activator of nuclear factor kappa-B ligand-mediated osteoclast differentiation and bone resorption by Gryllus bimaculatus extract: An in vitro study.

Excessive bone-resorbing osteoclast activity during bone remodeling is a major feature of bone diseases, such as osteoporosis. Therefore, the inhibition of osteoclast formation and bone resorption can be an effective therapeutic target for various bone diseases. Gryllus biomaculatus (GB) has recently been approved as an alternative food source because of its high nutritional value and environmental sustainability. Traditionally, GB has been known to have various pharmacological properties, including antipyretic and blood pressure-lowering activity, and it has recently been reported to have various biological activities, including protective effects against inflammation, oxidative stress, insulin resistance, and alcohol-induced liver injury. However, the effect of GB on osteoclast differentiation and bone metabolism has not yet been demonstrated. In this study, we confirmed the inhibitory effect of GB extract (GBE) on the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast formation. To determine the effect of GBE on RANKL-induced osteoclast differentiation and function, we performed TRAP and F-actin staining, as well as a bone-resorbing assay. The intracellular mechanisms of GBE responsible for the regulation of osteoclastogenesis were revealed by Western blot analysis and quantitative real-time polymerase chain reaction. We investigated the relationship between GBE and expression of osteoclast-specific molecules to further elucidate the underlying mechanisms. It was found that GBE significantly suppressed osteoclastogenesis by decreasing the phosphorylation of Akt, p38, JNK, and ERK, as well as Btk-PLCγ2 signaling, in pathways involved in early osteoclastogenesis as well as through the subsequent suppression of c-Fos, NFATc1, and osteoclastogenesis-specific marker genes. Additionally, GBE inhibited the formation of F-actin ring-positive osteoclasts and bone resorption activity of mature osteoclasts. Our findings suggest that GBE is a potential functional food and therapeutic candidate for bone diseases involving osteoclasts.

Pregnancy outcomes of immigrant women living in Korea: A population-based study.

Although there is a high rate of pregnant immigrant women in Korea, little is known regarding their pregnancy outcomes. The aim of this study was to evaluate the pregnancy outcomes of immigrant women in Korea. Data for all pregnant women who gave birth between January 1, 2007 and December 31, 2016 were obtained using the Health Insurance Review and Assessment Service Database. Pregnant women were divided into two groups: Korean and immigrant women. The main outcome measures were adverse pregnancy outcomes including gestational diabetes of mellitus, preeclampsia, cesarean section, placental abrnomalities, and postpartum hemorrhage. The odds of gestational diabetes mellitus, preeclampsia, cesarean section, placental previa, placental abruptio, and postpartum hemorrhage was compared between the two groups. Among 4,439,778 pregnant women who gave birth during the study period, 168,940 (3.8%) were immigrant women. The odds of gestational diabetes mellitus (adjusted OR: 1.24; 95% CI: 1.21, 1.28), and cesarean section (adjusted OR: 1.26; 95% CI: 1.25-1.28)were higher in immigrant women than in Korean women, but the odds of preeclampsia (adjusted OR: 0.84; 95% CI: 0.81-0.86) and postpartum hemorrhage (adjusted OR 0.96, 95% CI 0.94-0.97) was lower in immigrant women than in Korean women. Immigrant women had different pregnancy outcomes. Pregnancy and postpartum management that reflects these characteristics will be necessary for immigrant women.

Pitavastatin prevents ovariectomy-induced osteoporosis by regulating osteoclastic resorption and osteoblastic formation.

Excessive osteoclast activity, along with relatively weak osteoblast function, is strongly associated with bone disease. Therefore, studies to identify novel anti-osteoporosis candidates with dual actions of inhibiting osteoclastogenesis and increasing osteoblastogenesis may provide an ideal approach for treating osteoporosis. Pitavastatin, an inhibitor of 3-hydroxy-3 methyl-glutaryl coenzyme A reductase, has demonstrated various pharmacological activities, including anti-inflammation, bone anabolic effects, vasodilation, and inhibition of revascularization; however, the precise effects and mechanisms of pitavastatin on the regulation of osteoblast and osteoclast activity need to be comprehensively elucidated. Herein, we demonstrated that pitavastatin is a potential candidate for treating osteoporosis by enhancing osteoblast differentiation and bone growth and inhibiting osteoclast differentiation and bone resorption. Pitavastatin exerted dose-dependent inhibitory effects on receptor activator of nuclear factor kappa-B ligand-induced osteoclast formation, bone resorption, and osteoclast-specific marker gene expression. These inhibitory effects were achieved by inhibiting the Akt, NF-κB, and mitogen-activated protein kinase (p38, ERK, and JNK) signaling pathways, resulting in the downregulation of major transcription factors c-Fos and NFATc1. Furthermore, pitavastatin potentially stimulated osteoblast differentiation by activating alkaline phosphatase (ALP), enhancing mineralization by Alizarin Red S, and increasing the expression of osteoblastogenic marker genes such as runt-related transcription factor 2, ALP, osteocalcin, and collagen type 1 alpha. Furthermore, we evaluated the therapeutic potential of pitavastatin in ovariectomy-induced systematic bone loss based on micro-computed tomography and histological analysis of femurs. Our findings demonstrated a new function and mechanism for pitavastatin in bone remodeling, indicating its potential as a therapeutic candidate in treating osteoporosis by inhibiting osteoclastic resorption and promoting osteoblastic formation.

ß-Boswellic Acid Inhibits RANKL-Induced Osteoclast Differentiation and Function by Attenuating NF-κB and Btk-PLCγ2 Signaling Pathways.

Osteoporosis is a systemic metabolic bone disorder that is caused by an imbalance in the functions of osteoclasts and osteoblasts and is characterized by excessive bone resorption by osteoclasts. Targeting osteoclast differentiation and bone resorption is considered a good fundamental solution for overcoming bone diseases. ß-boswellic acid (ßBA) is a natural compound found in Boswellia serrata, which is an active ingredient with anti-inflammatory, anti-rheumatic, and anti-cancer effects. Here, we explored the anti-resorptive effect of ßBA on osteoclastogenesis. ßBA significantly inhibited the formation of tartrate-resistant acid phosphatase-positive osteoclasts induced by receptor activator of nuclear factor-B ligand (RANKL) and suppressed bone resorption without any cytotoxicity. Interestingly, ßBA significantly inhibited the phosphorylation of IκB, Btk, and PLCγ2 and the degradation of IκB. Additionally, ßBA strongly inhibited the mRNA and protein expression of c-Fos and NFATc1 induced by RANKL and subsequently attenuated the expression of osteoclast marker genes, such as OC-STAMP, DC-STAMP, ß3-integrin, MMP9, ATP6v0d2, and CtsK. These results suggest that ßBA is a potential therapeutic candidate for the treatment of excessive osteoclast-induced bone diseases such as osteoporosis.

Nationwide population-based cohort study of adverse obstetric outcomes in pregnancies with myoma or following myomectomy: retrospective cohort study.

BACKGROUND: Our objective was to evaluate risks of adverse obstetric outcomes in pregnancies with myoma(s) or in pregnancies following myomectomy. METHODS: We analyzed the national health insurance database, which covers almost the entire Korean population, between 2004 and 2015. The risks of adverse pregnancy outcomes in pregnancies with myoma(s) or in pregnancies following myomectomy, compared to those in women without a diagnosed myoma, were analyzed in multivariate logistic regression analysis. RESULTS: During the study period, 38,402 women with diagnosed myoma(s), 9890 women with a history of myomectomy, and 740,675 women without a diagnosed myoma gave birth. Women with a history of diagnosed myoma(s) and women with a history of myomectomy had significantly higher risks of cesarean section (aOR 1.13, 95% CI 1.1-1.16 and aOR 7.46, 95% CI 6.97-7.98, respectively) and placenta previa (aOR 1.41, 95% CI 1.29-1.54 and aOR 1.58, 95% CI 1.35-1.83, respectively), compared to women without a diagnosed myoma. And the risk of uterine rupture was significantly higher in women with previous myomectomy (aOR 12.78, 95% CI 6.5-25.13), compared to women without a diagnosed myoma, which was much increased (aOR 41.35, 95% CI 16.18-105.69) in nulliparous women. The incidence of uterine rupture was the highest at delivery within one year after myomectomy and decreased over time after myomectomy. CONCLUSIONS: Women with a history of myomectomy had significantly higher risks of cesarean section and placenta previa compared to women without a diagnosed myoma.

Investigations for postmenopausal uterine bleeding: special considerations for endometrial volume.

BACKGROUND: Postmenopausal bleeding is a clinically important complaint in general gynecologic practice. The incidence of spontaneous postmenopausal bleeding in the general population is approximately 10 % immediately after menopause, and 5 % in all menopausal women. OBJECTIVES: The study was aimed to reveal the histopathologic diagnosis of postmenopausal uterine bleeding, and to investigate the correlation between various clinical factors and endometrial carcinoma. We also evaluated the role of endometrial volume calculation in the clinical use for the endometrial histopathologic findings. MATERIALS AND METHODS: In this prospective observational study, we recruited 163 postmenopausal women with abnormal uterine bleeding from January 2008 through December 2010. Women who had hematologic disease, or had nonuterine pelvic diseases were excluded. Clinical characteristics such as age, body mass index (BMI), associated diseases, and previous postmenopausal hormone therapy were checked. They were evaluated by transvaginal ultrasonography and underwent endometrial biopsy for the endometrial histopathologic examination. RESULTS: Among the endometrial histopathologic findings, atrophic endometrium was the most common finding (32.7 %), followed by hyperplastic endometrium (10.4 %), endometrial carcinoma (10.4 %), and endometrial polyp (9.2 %). The prevalence of endometrial hyperplasia and cancer was not significantly different at the 5 mm cut-off thickness of the endometrium, but significantly higher in women with ≥ 3 mL of endometrial volume. However, the incidence of endometrial cancer and hyperplasia in women with endometrial bleeding was not significantly different with or without previous or current hormone therapy. CONCLUSIONS: Endometrial biopsy should be performed to exclude endometrial hyperplasia and carcinoma in postmenopausal women with endometrial bleeding to perform proper and prompt treatment, especially in old aged women (> 60 years) and in patients with endometrial volume ≥ 3 mL.

Inhibition of osteoclast differentiation and bone resorption by rotenone, through down-regulation of RANKL-induced c-Fos and NFATc1 expression.

Osteoclasts are responsible for bone erosion in diseases as diverse as osteoporosis, periodontitis, and rheumatoid arthritis. Natural plant-derived products have received recent attention as potential therapeutic and preventative drugs in human disease. The effect of rotenone in RANKL-induced osteoclast differentiation was examined in this study. Rotenone inhibited RANKL-mediated osteoclast differentiation in bone marrow macrophages (BMMs) in a dose-dependent manner without any evidence of cytotoxicity. The mRNA expression of c-Fos, NFATc1, TRAP, and OSCAR in RANKL-treated BMMs was inhibited by rotenone treatment. Rotenone strongly inhibited p38 and ERK phosphorylation and I-kappaB degradation in RANKL-stimulated BMMs, and did not inhibit JNK phosphorylation. Further, RANKL-induced c-Fos and NFATc1 protein expression was suppressed by rotenone. Rotenone additionally inhibited the bone resorptive activity of differentiated osteoclasts. A lipopolysaccharide (LPS)-induced bone erosion study was also performed to assess the effects of rotenone in vivo. Mice treated with rotenone demonstrated marked attenuation of bone erosion based on Micro CT and histologic analysis of femurs. These results collectively suggested that rotenone demonstrated inhibitory effects on osteoclast differentiation in vitro and suppressed inflammatory bone loss in vivo. Rotenone may therefore serve as a useful drug in the prevention of bone loss.

Risedronate directly inhibits osteoclast differentiation and inflammatory bone loss.

Risedronate, a nitrogen-containing bisphosphonate, is widely used in the clinical field for the treatment of osteoporosis. Risedronate is known to exert its effects through binding to hydroxyapatite in bone tissue, inhibiting osteoclastic activity, and inducing apoptosis of osteoclasts. The purpose of this study was to determine the effects of risedronate on osteoclast differentiation in vitro and on an inflammatory bone loss model in vivo. Risedronate inhibited osteoclast differentiation in co-culture of bone marrow cells (BMCs) and osteoblasts, and suppressed receptor activator of nuclear factor (NF)-kappaB ligand (RANKL)-mediated osteoclast differentiation from bone marrow-derived macrophages (BMMs) in a dose-dependent manner without toxicity. Risedronate significantly inhibited expression of c-Fos and nuclear factor of activated T cells (NFAT) c1 induced by RANKL. To examine the effect of risedronate on bone loss in vivo, we used a mouse model of lipopolysaccharide (LPS)-mediated bone loss. Micro-CT analysis of the femurs showed that LPS treatment caused bone loss. However, bone loss was significantly attenuated in mice administered with risedronate. Taken together, we conclude that risedronate exerts beneficial effects on osteoporosis by inhibiting osteoclast differentiation both directly and indirectly. In infectious conditions, the inhibitory effect of risedronate on bone erosion was excellent. Thus risedronate could be a treatment option for osteoporosis caused by inflammatory and infectious conditions.

Pyridone 6, a pan-Janus-activated kinase inhibitor, suppresses osteoclast formation and bone resorption through down-regulation of receptor activator of nuclear factor-kappaB (NF-kappaB) ligand (RANKL)-induced c-Fos and nuclear factor of activated T cells (NFAT) c1 expression.

It has been reported that Janus tyrosine kinase (JAK)-dependent signaling pathways play a critical role in the pathogenesis of numerous malignancies and immune reactions, and inhibition of JAK has been implicated in cell growth inhibition. The role which JAK has on osteoclast differentiation and anti-bone resorptive activity is not well understood. In this study, we investigated the effects of a pan-JAK inhibitor, pyridone 6, on osteoclast differentiation and bone-resorption in vitro and ex vivo. Pyridone 6 inhibited osteoclast differentiation in mouse bone marrow macrophage (BMM) cultures stimulated by the receptor activator of nuclear factor-kappaB (NF-kappaB) ligand (RANKL) and co-cultures of bone marrow cells and osteoblasts. Pyridone 6 suppressed the expression of c-Fos and nuclear factor of activated T cells (NFAT) c1 in BMMs. It also inhibited the bone resorptive activity of mature osteoclasts that was accompanied by disruption of actin rings. Pyridone 6 also suppressed I-kappaB degradation and extracellular signal-regulated kinase (ERK) in mature osteoclasts, suggesting that these are the key molecules that pyridone 6 targets in the inhibition of osteoclast function. These results demonstrate inhibition of JAK may be useful for the treatment of bone-resorptive diseases, such as osteoporosis.

Proteasome inhibitors induce osteoclast survival by activating the Akt pathway.

Osteoclasts rapidly undergo spontaneous apoptosis when deprived of survival factors. Regulation of osteoclast survival is important to treat bone-related diseases, such as osteoporosis. In this study, we found that the proteasome inhibitors, MG132 and ALLN, significantly inhibited osteoclast apoptosis induced by etoposide, as well as under conditions of survival factor deprivation. MG132 and ALLN inhibited the release of cytochrome c from mitochondria into the cytosol in the absence of survival factors and suppressed the cleavage of pro-caspase-9 and -3 to its active forms induced by etoposide. In addition, MG132 and ALLN enhanced the phosphorylation of Akt and ERK in osteoclasts. However, MG132 and ALLN did not inhibit the cleavage of caspase-9 and -3 in the presence of the phosphatidylinositol 3-kinase (PI-3K) inhibitor, LY294002, while the inhibitory effect of MG132 and ALLN were intact in presence of the MEK1/2 inhibitor, U0126. LY294002 inhibited the survival of osteoclasts induced by MG132 and ALLN. Taken together, our results have demonstrated that proteasome inhibitors suppressed osteoclast apoptosis under conditions of survival factors deprivation through activation of the PI-3K/Akt pathway.