The bones of the human body support the structures of the body and provide protection for a person’s internal organs. Bone metabolic diseases are on the rise due to a significant increase in life expectancy over a short period of time. Therefore, we investigated the osteoblast differentiation promoting and osteoclastogenesis inhibitory activities of fermented Benincasa hispida cong. (HR1901-BS, HR1901-BSaf). We evaluated the alkaline phosphatase (ALP) activity of MC3T3-E1 mouse calvarial-derived osteoblasts. We also evaluated expression of ALP, osteocalcin (OCN), and runt-related transcription factor 2 (Runx2), which regulate osteoblast differentiation. To assess effects on osteoclast formation, tartrate-resistant acid phosphatase (TRAP) activity in RAW264.7 cells was analyzed. ALP activity increased by 121-136% and 140-156%, respectively in the presence of HR1901-BS and HR1901- BSaf. Expression of osteoblast differentiation factor also increased significantly. We also confirmed that HR1901-BS and HR1901-BSaf decreased TRAP activity in osteoclasts by 35-47% and 23-39%, respectively. Our results showed that fermented Benincasa hispida cong. (HR1901-BS, HR1901-BSaf) increase bone mineralization and osteoblast differentiation activity in MC3T3-E1 cells, and inhibit bone resorption activity in RAW264.7 cells. In conclusion, fermented Benincasa hispida cong. (HR1901-BS, HR1901-BSaf) can be used as an effective natural resource for preventing and treating bone-related diseases.
본 연구는 방사선 육종 차조기와 백출 복합물의 조골세포 분화 활성 및 파골세포 형성 억제를 조사하였다. 차조기와 백출 복합물은 MG-63 세포에서 ALP 활성 및 arlizarin red 염색을 확인하였고 조골세포 형성의 영향은 RAW 264.7 세포에서 TRAP 활성과 TRAP 염색을 진행하였다. 세포 독성 시험에서 차조기와 백출 복합물은 50 ㎍/㎖ 농도 이하에서 안전한 것으로 확인되었다. ALP 활성 및 골석회화 형성 능력은 대조군보다 활성이 낮았으나, 파골세포에서 TRAP 활성을 유의적으로 감소시켰으며, 효과적으로 TRAP(+) 다핵세포를 억제하였다. 따라서 차조기와 백출 복합물은 골 흡수 억제 활성을 향상시켜 뼈 관련 질환의 예방 및 치료에 효과적인 것으로 보여진다.
Osteoporosis is a common disease characterized by bone mass reduction, leading to an increased risk of bone fracture, and it is caused by an imbalance of osteoblastic bone formation and osteoclastic bone resorption. Current osteoporosis drugs aim to reduce the risk of bone fracture, either by increasing osteoblastic bone formation or decreasing osteoclastic bone resorption. However, osteoblasts and osteoclasts are closely coupled, such that any reagent altering the differentiation or activity of one eventually affects the other. This tight coupling between osteoblasts and osteoclasts not only limits the therapeutic efficacy but also threatens the safety of osteoporosis drugs. This review will discuss the biological mechanisms of action of currently approved medications for osteoporosis treatment, focusing on the osteoblast–osteoclast coupling.
Connective tissue growth factor (CTGF, CCN2) is one of the multi-functional secreted proteins which belong to CCN family of cysteine-rich growth factors. CTGF is known to have pivotal roles in embryonic endochondral ossification but its role in relevance to periodontitis is never been determined. To identify new molecular mediators associated with periodontitis-induced bone resorption, we have analyzed publicly available GEO database and found the markedly augmented CTGF mRNA expression in periodontitis gingival tissues. The existence of CTGF significantly enhanced mature osteoclasts survival which accompanied by reduction in TUNEL-positive nuclei and PARP cleavage. These results may provide another line of evidence the CTGF mediated prolonged osteoclast survival and subsequent increased bone resorption in the periodontitis patients.
췌장의 파골세포양 거대세포 미분화 암종은 그 발생 빈도는 드물지만 높은 악성도를 가지는 외분비 췌장암이다. 췌장 의 파골세포양 거대세포 미분화 암종은, 복부 전산화단층촬 영에서 괴사와 출혈을 동반한 낭성 및 고형 종괴의 소견을 보이며, 다른 췌장의 낭성 종양과 감별이 필요하다. 현재까 지 명확하게 정립된 치료법은 없으며, 조기 진단 및 종양의 완전 절제만이 생존률 향상을 가져온다고 보고되고 있다. 본 증례는 58세 남성 환자에서 발생한 췌장의 파골세포양 거대 세포 미분화 암종이 수술 및 항암치료에도 불구하고 연조직 전이로 진행하여 사망한 1예로 문헌고찰과 함께 보고한다.
Cementum is the mineralized tissue of the tooth. It is similar to bone in several aspects but it differs from bone. Human bone marrow stromal cells (BMSC) and human cementum derived cells (HCDC) (10,000 cells/cm²) were plated in 6 well plates as feeder cells. The next day, mouse bone marrow cells (1.5 million cells/cm²) were added. One group of these plates were incubated in serum-free conditioned medium (SFCM) generated from BMSC or HCDC supplemented with 2% FBS, parathyroid hormone (PTH), 1, 25 dihydroxyvitamin D₃ (Vit. D₃) and dexamethasone, or plain medium with the same supplements. Another group of plates were cocultured with BMSC or HCDC in plain medium supplemented with 2% FBS, PTH, Vit. D₃and dexamethasone. Plates grown without SFCM or coculture were used as controls. After 10 days, the cells were stained for tartrate-resistant acid phosphatase (TRAP). BMSC were found to support osteoclast formation under normal conditions. This was inhibited however by both SFCM generated from HCDC and also by coculture with HCDC. In addition, HCDC themselves did not support osteoclast formation under any conditions. Our results thus indicate that HCDC do not support osteoclast formation in vitro and that soluble factor (s) from HCDC may inhibit this process. In addition, we show that this inhibition also involves an active mechanism that is independent of osteoprotegerin, a feature that may distinguish cementoblasts from other cells present in periodontium.
Hydroxyapatite (HAp) and biphasic calcium phosphate (BCP) nano powders were synthesized using the microwave-assisted synthesis process dependent on pH and microwave irradiation time. The average size of a powder was less than 100 nm in diameter. Through in-vitro cytotoxicity tests by an extract dilution method, the HAp and BCP nano powders have shown to be cytocompatible for L-929 fibroblast cells, osteoblastlike MG-63 cells and osteoclast-like Raw 264.7 cells. The activation of osteoblast was estimated by alkaline phosphatase (ALP) activity. When the HAp and BCP were treated to MG-63 cells, alkaline phosphatase activities increased on day 3, compared with those of the untreated cells. Also, the collagen fibers increased when the HAp and BCP powders suspension were treated to MG-63 cells, compared to those of the untreated cells. Quantitative alizarin red S mineralization assays showed a trend toward increasing mineralization in osteoblast cultured with powder suspension. In conclusion, hydroxyapatite and biphasic calcium phosphate appeared to be a bone graft substitute material with optimal biocompatibility and could be further applied to clinical use as an artificial bone graft substitute.
Dlx3 is a homeodomain protein and is known to playa role in development and differentiation of many tissues. Deletion of four base pairs in DLX3 (NT3198) is causally related to tricho-dento-osseous (TDO) syndrome (OMIM # 190320), a genetic disorder manifested by taurodontism, hair abnormalities, and increased bone density in the cranium. Although the observed defects of TDO syndrome involves bone, little is known about the role of Dlx3 in bone remodeling process. In this study, we examined the effect of wild type DLX3 (wtDlx3) expression on osteoclast differentiation and compared it with that of 4-BP DEL DLX3 (TDO mtDlx3). To examine whether Dlx3 is expressed during RANKL-induced osteoclast differentiation, RAW264.7 cells were cultured in the presence of receptor activator of nuclear factor-B ligand (RANKL). Dlx3 protein level increased slightly after RANKL treatment for 1 day and peaked when the fusion of prefusion osteoclasts actively progressed. When wtDlx3 and TDO mtDlx3 were overexpressed in RAW264.7 cells, they enhanced RANKL-induced osteoclastogenesis and the expression of osteoclast differentiation marker genes such as calcitonin receptor, vitronectin receptor and cathepsin K. Since osteoclast differentiation is critically regulated by the balance between RANKL and osteoprotegerin (OPG), we examined the effect of Dlx3 overexpression on expression of RANKL and OPG in C2C12 cells in the presence of bone morphogenetic protein 2. Overexpression of wtDlx3 enhanced RANKL mRNA expression while slightly suppressed OPG expression. However, TDO mtDlx3 did not exert significant effects. This result suggests that inability of TDO mtDlx3 to regulate expression of RANKL and OPG may contribute to increased bone density in TDO syndrome patients. Taken together, it is suggested that Dlx3 playa role as a positive regulator of osteoclast differentiation via up-regulation of osteoclast differentiation-associated genes in osteoclasts, as well as via increasing the ratio of RANKL to OPG in osteoblastic cells.
We performed the present study to investigate whether Rehmannia glutinosa Libosch (RG) extracts (RGX) and Eleutherococcus senticosus Max (ES) extracts (ESX) play any roles in bone metabolism. We examined cellular activities of bone cells by measurement of osteoblastic cell viability, osteoprotegerin (OPG) secretion from osteoblasts, osteoclastogenesis, and osteoclastic activity. There is no cytotoxicity from osteoblasts after treatment with RGX and ESX. The secretion of OPG from the osteoblasts showed marked increases after treatment with RGX and ESX. In addition, RGX and ESX treatment decreased the number of tartrate-resistant acid phosphatase-positive multinucleated cells and the resorption areas. RGX and ESX, when mixed at optimal ratios, induced synergic effects, in vitro. OPB, which showed synergic effects, is the extract of natural ingredients RG and ES mixed at a raw material weight ratio of 4 : 1. It can be suspected that extracts of RG and ES mixtures contains active ingredients involved in bone tissue metabolism and may be effective in improving osteoporosis.
Nitric oxide(NO) is a labile, uncharged, reactive radical that functions as a sensitive mediator of intercellular communication in diverse tissues. It has been reported that NO is produced by osteoblast and these results may suggest that NO is integrally involved in the regulation of osteoclast formation and osteoclast resorption activity by osteoblastic cells. We examined the effect of cytokines on NO release by mouse bone marrow cell. We also examined the effects of cytokines and sodium nitroprusside(SNP) on the formation of osteoclast-like cell from mouse bone marrow cells in culture. Cytokines stimulated NO production of mouse bone marrow cells, and N-nitro-L-arginine methyl ester, a specific inhibitor of NO synthase, suppressed the cytokine-induced NO production. SNP showed dual action in the generation of osteoclasts. The addition of (30μM)SNP inhibited the formation of tartrate resistant acid phosphatase(TRAP)(+) multinucleated cell, whereas lower concentration(30μM) of SNP enhanced it. Although the precise action of NO remains to be elucidated in detail, the action of NO in osteoclast generation in our studies seems to be associated, at least in part, with bone metabolism and bone pathophysiology.
Although it has been known that TGF-β1 acts as a crucial cofactor in osteoclast differentiation, its mode of action is still unclear. In the present study, we studied the effect of TGF-β1 on the differentiation of osteoclast depending on the developmental stages. Murine bone marrow cells were induced to differentiate into mature osteoclasts in the presence of receptor activator of NF-xβ ligand (RANKL) and macrophage colony stimulating factor (M-CSF). In the early stage of the differentiation TRAP(-) mononuclear precursor cells were obtained from nonadherent M-CSF dependent bone marrow cells, which further differentiated into mature osteoclasts. TGF-β1 stimulated osteoclast differentiation, which was stronger when cells were stimulated by TGF-β1 in the early stage than the later differentiation. TGF-β1 increased the expression of RANK and synergistically stimulated RANKL-induced activation of NF-xβ MAP kinase in TRAP(-) mononuclear precursor cells. These results suggest that activation of osteoclast differentiation by TGF-β1 may be ascribed to the both increased expression and activation of RANK in the osteoclast differentiation, especially in the early stage of differentiation.
Osteoclasts are multinucleated cells with bone resorbing activity and differentiated from hematopoietic cell lineages of monocyte/macrophages in the presence of receptor activator of NF-xB ligand (RANKL) and M-CSF. However, the exact molecular mechanisms through which RANKL stimulates osteoclastogenesis remain to be elucidated. Here we report that activation of cAMP-response elementbinding protein (CREB) is not involved in osteoclastogenesis from osteoclast precursors in response to RANKL. RANKL induced CREB activation in osteoclast precursors. Using pharmacological inhibitors, we found that RANKL-induced CREB activation is dependent on p38 MAPK pathways. We also found that ectopic expressions of wild type and dominant negative forms of CREB in osteoclast precursors did not affect RANKL-induced osteoclast formation and bone resorbing activity. Furthermore, dominant negative forms of CREB did not alter the expression levels of osteoclast-specific marker genes. Taken together, these data suggest that CREB is dispensable for differentiation and resorbing activity of osteoclasts.
Leptin, the product of the obese gene, is a circulating hormone secreted primarily from adipocytes. Several results suggest that leptin is important mediators of bone metabolism. The present study was undertaken to determine the effects of leptin on anti-osteoclastogenesis using murine precursors cultured on Ca-P coated plates and on the production of osteoprotegerin (OPG) in osteoblastic cells. Additionally, this study examined the possible involvement of prostaglandin E₂(PGE₂)/вввB/protein kinase C (PKC)-mediated signals on the effect of leptin on anti-osteoclastogenesis to various culture systems of osteoclast precursors. Osteoclast generation was determined by counting tartrate-resistant acid phosphatase positive [TRAP (+)] multinucleated cells (MNCs). Osteoclastic activity was determined by measuring area of resorption pits formed by osteoclasts on Ca-P coated plate. The number of 1,25-dihydroxycholecalciferol 1.25[OH]₂D₃- or PGE₂-induced TRAP (+) MNCs in the mouse bone marrow cell culture decreased significantly after treatment with leptin. The number of receptor activator of NF-kB ligand (RANKL)-induced TRAP (+) MNCs in M-CSF dependent bone marrow macrophage (MDBM) cell or RAW264.7 cell culture decreased significantly with leptin treatment. Indomethacin inhibited osteoclast generation induced by 1.25[OH]₂D₃ and dexamethasone, however, no significant differences were found in the leptin treated group when compared to the corresponding indomethacin group. Phorbol 12-myristate 13-acetate (PMA), a PKC activator, inhibited osteoclast generation induced by 1.25[OH]₂D₃The number of TRAP (+) MNCs decreased significantly with treatment by PMA at concentrations of 0.01 and 0.1μM in culture. Leptin inhibited PMA-mediated osteoclast generation. Isoquinoline-5-sulfonic 2-methyl-1-piperazide dihydrochloride (H7) had no effect on osteoclast generation induced by 1.25[OH]₂D₃ Cell culture treatment with leptin resulted in no significant differences in osteoclast generation compared to the corresponding H7 group. Indomethacin showed no significant effect on TRAP (+) MNCs formation from the RAW264.7 cell line. PMA inhibited TRAP (+) MNCs formation induced by RANKL in the RAW264.7 cell culture. H7 had no effect on osteoclast generation from the RAW264.7 cell line. There was no difference compared with the corresponding control group after treatment with leptin. 1.25[OH]₂D₃- or PGE₂-induced osteoclastic activity decreased significantly with leptin treatment at a concentration of 100 ng/ml in mouse bone marrow cell culture. Indomethacin, PMA, and H7 significantly inhibited osteoclastic activity induced by 1.25[OH]₂D₃ in mouse bone marrow cell culture. No significant differences were found between the leptin treated group and the corresponding control group. The secretion of OPG, a substance known to inhibit osteoclast formation, was detected from the osteoblasts. Treatment by leptin resulted in significant increases in OPG secretion by osteoblastic cells. Taken these results, leptin may be an important regulatory cytokines within the bone marrow microenvironment.