• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권5호
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• pp.392-401
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• 2010

Introduction: Diabetes mellitus, as a major health problem for the elderly has been shown to alter the properties of the bone and impair bone healing around a titanium implant in both humans and animals. The aim of this study was to examine the effect of adipose-derived stem cells on the healing process around a titanium implant in streptozotocin-induced diabetic rats. Materials and Methods: Thirteen rats were divided into two groups: adipose-derived stem cells injected group and a control group. A titanium screw implant (diameter: 2.0 mm, length: 3.5 mm) was placed into both tibia of 13 rats: 13 right tibia as the control group and 13 left tibia as the experimental group. The rats were sacrificed at different intervals (1, 2, and 4 weeks) after implantation for histopathology observations and immunohistochemistric analysis. Results: The histopathological findings revealed earlier new formed bone in the experimental group than the control group. In particular, at 1 week after implantation, the experimental group showed more newly formed bone and collagen around the implant than the control group. In immunohistochemistric analysis, osteoprotegerin (OPG) expression in the experimental group increased early compared to that of the control group until 2 weeks after implantation. However, after 2 weeks, OPG expression in the experimental group was similar to OPG expression in the control group. The receptor activator of nuclear factor ${\kappa}B$ ligand (RANKL) expression in the experimental group increased early compared to that of the control group, and then decreased at 2 weeks. After 2 weeks, the level of RANKL expression was similar in both groups. Conclusion: These results suggest that adipose-derived stem cells in implantation can promote bone healing around titanium, particularly in diabetes mellitus induced animals.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권5호
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• pp.386-391
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• 2010

Introduction: Bone resorption is a unique function of osteoclasts. Osteoclasts are a specialized macrophage polykaryon whose differentiation is regulated principally by macrophage colony-stimulating factors, receptor activator of nuclear factor ${\kappa}B$ ligand (RANK) ligand, osteoprotegerin (OPG), and interleukins (IL). Reflecting the integrin-mediated signals, osteoclasts develop a specialized cytoskeleton that allows it to establish an isolated micro-environment between itself and the bone, wherein matrix degradation occurs by a process involving proton transport. The levels of IL-1, IL-6, OPG, and prostaglandin $E_2$ ($PGE_2$) expression were evaluated to study the correlations between dental implant teeth and the adjacent teeth. Materials and Methods: The exudate of the gingival crevice acquired from dental implants, adjacent teeth, opposite teeth and contralateral teeth of 24 patients. Results: 1. The levels of IL-1, IL-6, OPG and $PGE_2$ expression in dental implant teeth were higher than those of the contralateral teeth. 2. IL-1 revealed a higher expression level in the adjacent teeth than in dental implant teeth. 3. The dental implant teeth and adjacent teeth did not show a remarkable difference in the level of IL-1 expression. 4. All the other cytokines were strongly expressed in the dental implant compared to the adjacent teeth. Conclusion: These results suggest that there might be close correlation between dental implant teeth and adjacent teeth in terms of the expressions of cytokines that affect the development and regulation of osteoclasts.

• 한국식품영양과학회지
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• 제39권1호
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• pp.64-70
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• 2010

본 연구는 MC3T3-E1 조골 전구세포에 대두추출물을 처리 후 그 조건배양액에서 파골세포분화 관련 국소인자 중파골세포분화 촉진인자(IL-$\beta$, IL-6, RANKL, TNF-$\alpha$, M-CSF) 및 파골세포로의 분화억제에 관여하는 국소인자인 OPG의 발현변화를 조골세포 조건배양액에서 살펴보았으며, 이 조골세포 조건배양액을 RAW264.7 파골전구세포에 처리 시 파골세포로의 분화를 억제정도를 TRAP 염색 및 관련 분화 지표의 발현을 통해 알아보았다. 대두추출물 처리한 조골세포 조건배양액에서 OPG의 발현이 농도 의존적으로 현저히 증가하였다. 그러나 강력한 파골세포 분화촉진인자로 알려진 IL-1$\beta$의 발현 역시 고농도의 대두추출물 처리 시 현저히 증가하여 고농도의 대두추출물을 처리한 CM 처리 시 TRAP 염색된 일부 파골세포를 확인하였고, 파골세포분화 관련지표인 MMP-9의 발현 또한 저농도 대두 추출물을 처리한 CM 처리에 비해 증가하였다. 이는 저농도의 대두추출물이 고농도의 대두추출물에 비해 파골세포분화억제에 효과적임을 의미하나, 추후 파골세포수준에서 분화억제 관련 기전연구가 필요할 것으로 생각되어진다.

• Tuberculosis and Respiratory Diseases
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• 제78권3호
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• pp.218-226
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• 2015

Background: Eph receptors and ephrin ligands have several functions including angiogenesis, cell migration, axon guidance, fluid homeostasis, oncogenesis, inflammation and injury repair. The EphA2 receptor potentially mediates the regulation of vascular permeability and inflammation in response to lung injury. Methods: Mice were divided into 3 experimental groups to study the role of EphA2 signaling in the lipopolysaccharide (LPS)-induced lung injury model i.e., IgG+phosphate-buffered saline (PBS) group (IgG instillation before PBS exposure), IgG+LPS group (IgG instillation before LPS exposure) and EphA2 monoclonal antibody (mAb)+LPS group (EphA2 mAb pretreatment before LPS exposure). Results: EphA2 and ephrinA1 were upregulated in LPS-induced lung injury. The lung injury score of the EphA2 mAb+LPS group was lower than that of the IgG+LPS group ($4.30{\pm}2.93$ vs. $11.45{\pm}1.20$, respectively; p=0.004). Cell counts (EphA2 mAb+LPS: $11.33{\times}10^4{\pm}8.84{\times}10^4$ vs. IgG+LPS: $208.0{\times}10^4{\pm}122.6{\times}10^4$; p=0.018) and total protein concentrations (EphA2 mAb+LPS: $0.52{\pm}0.41mg/mL$ vs. IgG+LPS: $1.38{\pm}1.08mg/mL$; p=0.192) were decreased in EphA2 mAb+LPS group, as compared to the IgG+LPS group. In addition, EphA2 antagonism reduced the expression of phospho-p85, phosphoinositide 3-kinase $110{\gamma}$, phospho-Akt, nuclear factor ${\kappa}B$, and proinflammatory cytokines. Conclusion: This results of the study indicated a role for EphA2-ephrinA1 signaling in the pathogenesis of LPS-induced lung injury. Furthermore, EphA2 antagonism inhibits the phosphoinositide 3-kinase-Akt pathway and attenuates inflammation.

• International Journal of Oral Biology
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• 제30권1호
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• pp.9-15
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• 2005

Recently, we reported that high extracellular calcium increased receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL) expression via p44/42 mitogen-activated protein kinase (p44/42 MAPK) activation in mouse osteoblasts. However, the mechanism for p44/42 MAPK activation by high extracellular calcium is unclear. In this study, we examined the role of intracellular calcium increase in high extracellular calcium-induced RANKL induction and p44/42 MAPK activation. Primary cultured mouse calvarial osteoblasts were used. RANKL expression was highly induced by 10 mM calcium treatment. Ionomycin, a calcium ionophore, also increased RANKL expression and activated p44/42 MAPK. U0126, an inhibitor of MEK1/2, an upstream activator of p44/42 MAPK, blocked the RANKL induction by both high extracellular calcium and ionomycin. High extracellular calcium increased the phosphorylation of proline-rich tyrosine kinase 2 (Pyk2), one of the known upstream regulators of p44/42 MAPK activation. Bisindolylmaleimide, an inhibitor of protein kinase C, did not block RANKL induction and p44/42 MAPK activation induced by high extracellular calcium. 2-Aminoethoxydiphenyl borate, an inhibitor of inositol 1,4,5-trisphosphate (IP3) receptor, blocked the RANKL induction by high extracellular calcium. It also partially suppressed the activation of Pyk2 and p44/42 MAPK. Cyclosporin A, an inhibitor of calcineurin, also inhibited high calcium-induced RANKL expression in dose dependent manner. However, cyclosporin A did not affect the activation of Pyk2 and p44/42 MAPK by high extracellular calcium treatment. These results suggest that 1) the increase in intracellular calcium via IP3-mediated calcium release is necessary for RANKL induction by high extracellular calcium treatment, 2) Pyk2 activation, but not protein kinase C, following the increase in intracellular calcium might be involved in p44/42 MAPK activation, and 3) calcineurin-NFAT activation by the increase in intracellular calcium is involved in RANKL induction by high extracellular calcium treatment.

• 동의생리병리학회지
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• 제26권6호
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• pp.869-873
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• 2012

Balance between bone-forming osteoblasts and bone-resorbing osteoclasts is important in bone homeostasis. Unusual balance between bone-forming osteoblasts and bone-resorbing osteoclasts leads to bone diseases, such as osteoporosis. Saururus chinensis has been widely used in oriental medicine. Saururus chinensis has been known that has antioxidant and anticancer effect. But, the effect of Saururus chinensis in osteoclast differentation remains unknown. We examined the effect of Saururus chinensis in receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL)-induced osteoclast differentiation. From the results of our study, we found that saururus chinensis clearly inhibited RANKL-induced osteoclast differentiation in bone marrow macrophages (BMM) in a dose dependent manner without toxicity. Saururus chinensis inhibited the phosphorylation of JNK, P38, AKT, and ERK induced by RANKL. The mRNA expression of NFATc1, TRAP, and OSCAR induced by RANKL was inhibited by Saururus chinensis treatment. Moreover Saururus chinensis suppressed the protein expression of c-Fos and NFATc1 in BMMs treated with RANKL. These results suggest that Saururus chinensis may be a useful drug in the treatment of bone-related disease.

• BMB Reports
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• 제49권10호
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• pp.554-559
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• 2016

Mycobacterium abscessus, a member of the group of non-tuberculous mycobacteria, has been identified as an emerging pulmonary pathogen in humans. However, little is known about the protective immune response of antigen-presenting cells, such as dendritic cells (DCs), which guard against M. abscessus infection. The M. abscessus gene MAB1843 encodes ᴅ-alanyl-ᴅ-alanine dipeptidase, which catalyzes the hydrolysis of ᴅ-alanyl-ᴅ-alanine dipeptide. We investigated whether MAB1843 is able to interact with DCs to enhance the effectiveness of the host's immune response. MAB1843 was found to induce DC maturation via toll-like receptor 4 and its downstream signaling pathways, such as the mitogen-activated protein kinase and nuclear factor kappa B pathways. In addition, MAB1843-treated DCs stimulated the proliferation of T cells and promoted Th1 polarization. Our results indicate that MAB1843 could potentially regulate the immune response to M. abscessus, making it important in the development of an effective vaccine against this mycobacterium.

• Biomolecules & Therapeutics
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• 제26권2호
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• pp.146-156
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• 2018

Spermidine is a naturally occurring polyamine compound that has recently emerged with anti-aging properties and suppresses inflammation and oxidation. However, its mechanisms of action on anti-inflammatory and antioxidant effects have not been fully elucidated. In this study, the potential of spermidine for reducing pro-inflammatory and oxidative effects in lipopolysaccharide (LPS)-stimulated macrophages and zebrafish was explored. Our data indicate that spermidine significantly inhibited the production of pro-inflammatory mediators such as nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$), and cytokines including tumor necrosis $factor-{\alpha}$ and $interleukin-1{\beta}$ in RAW 264.7 macrophages without any significant cytotoxicity. The protective effects of spermidine accompanied by a marked suppression in their regulatory gene expression at the transcription levels. Spermidine also attenuated the nuclear translocation of $NF-{\kappa}B$ p65 subunit and reduced LPS-induced intracellular accumulation of reactive oxygen species (ROS) in RAW 264.7 macrophages. Moreover, spermidine prevented the LPS-induced NO production and ROS accumulation in zebrafish larvae and was found to be associated with a diminished recruitment of neutrophils and macrophages. Although more work is needed to fully understand the critical role of spermidine on the inhibition of inflammation-associated migration of immune cells, our findings clearly demonstrate that spermidine may be a potential therapeutic intervention for the treatment of inflammatory and oxidative disorders.

• Journal of Ginseng Research
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• 제41권2호
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• pp.151-158
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• 2017

Background: Chong-Myung-Tang (CMT) extract is widely used in Korea as a traditional herbal tonic for increasing memory capacity in high-school students and also for numerous body ailments since centuries. The use of CMT to improve the learning capacity has been attributed to various plant constituents, especially black ginseng, in it. Therefore, in this study, we have first investigated whether black ginseng-enriched CMT extracts affected spatial learning using the Morris water maze (MWM) test. Their molecular mechanism of action underlying improvement of learning and memory was examined in vitro. Methods: We used two types of black ginseng-enriched CMT extracts, designated as CM-1 and CM-2, and evaluated their efficacy in the MWM test for spatial learning behavior and their anti-inflammatory effects in BV2 microglial cells. Results: Our results show that both black ginseng-enriched CMT extracts improved the learning behavior in scopolamine-induced impairment in the water maze test. Moreover, these extracts also inhibited nitric oxide production in BV2 cells, with significant suppression of expression of proinflammatory cytokines, especially inducible nitric oxide synthase, cyclooxygenase-2, and $interleukin-1{\beta}$. The protein expression of mitogen-activated protein kinase and nuclear $factor-{\kappa}B$ pathway factors was also diminished by black ginseng-enriched CMT extracts, indicating that it not only improves the memory impairment, but also acts a potent anti-inflammatory agent for neuroinflammatory diseases. Conclusion: Our research for the first time provides the scientific evidence that consumption of black ginseng-enriched CMT extract as a brain tonic improves memory impairment. Thus, our study results can be taken as a reference for future neurobehavioral studies.

• 생명과학회지
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• 제25권2호
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• pp.223-230
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• 2015

RCAN1은 calcineurin을 억제하는 내인성 단백질로 calcineurin-NFATc1 신호전달 경로와 관련된 질환의 병인에 중요한 역할을 담당한다. 특히 RCAN1-4 아형 유전자의 경우 NFATc1 전사인자에 의해 조절된다. RANKL 자극은 calcineurin-NFATc1 경로로 파골세포 분화를 유도하는데, RCAN1과 파골세포의 분화에 관련된 연구는 보고 된 바 없다. 따라서 본 연구는 RANKL 처리에 의해 파골세포 분화가 유도될 때 RCAN1이 calcineurin-NFATc1 경로에 미치는 영향을 in vitro에서 조사했다. 마우스로부터 분리한 골수단핵세포에 RANKL을 처리하여 파골세포 분화를 유도했다. RANKL 처리 후 조사 대상 유전자의 mRNA 발현과 단백질 발현을 각각 RT-PCR과 Western blot로써 측정했다. 마우스 RCAN1-4 vector를 파골전구세포인 RAW 264.7 단핵세포주와 골수단핵세포에 형질도입(transfection)시켜 RCAN1-4 유전자의 과발현을 유도했다. 형질도입 후 파골세포 분화의 형태적 변화는 TRAP 염색을 통해 관찰했다. RANKL 처리 후 NFATc1, calcineurin, RCAN1-4 mRNA 발현은 크게 증가했다. 단백질 발현의 경우 NFATc1과 RCAN1은 증가했으나 calcineurin은 대조군과 차이가 없었다. RCAN1-4 유전자의 과발현 유도 시 RCAN1-4 mRNA는 크게 증가되었으나 RCAN1 단백질 발현은 증가되지 않았다. 특히 RANKL 존재 시 RCAN1 유전자를 knock-down시켜도 RCAN1 발현은 정상적으로 유지되었다. 한편, NFATc1 발현은 과발현 유도시 감소했고 knock-down 유도 시 증가하는 경향을 보였다. RCAN1-4 유전자 과발현을 유도한 골수단핵세포에서 배양 5일 후 파골세포 분화는 대조군과 차이가 없었다. 이러한 결과는 RANKL에 의한 파골세포 분화 시 RCAN1이 calcineurin-NFATc1 경로를 통해 파골세포 분화에 미치는 영향은 제한적일 것으로 사료된다.