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Aim: Among numerous constituents of Panax ginseng, a constituent named Ginsenoside Rb1 (G‐Rb1) has been studied to diminish inflammation associated with diseases. This study investigated the anti‐inflammatory properties of G‐Rb1 on human dental pulp cells (hDPCs) exposed to lipopolysaccharide (LPS) and aimed to determine the underlying molecular mechanisms. Methodology: The KEGG pathway analysis was performed after RNA sequencing in G‐Rb1‐ and LPS‐treated hDPCs. Reverse‐transcription polymerase chain reaction (RT–PCR) and western blot analysis were used for the assessment of cell adhesion molecules and inflammatory cytokines. Statistical analysis was performed with one‐way ANOVA and the Student–Newman–Keuls test. Results: G‐Rb1 did not exhibit any cytotoxicity within the range of concentrations tested. However, it affected the levels of TNF‐α, IL‐6 and IL‐8, as these showed reduced levels with exposure to LPS. Additionally, less mRNA and protein expressions of vascular cell adhesion molecule‐1 (VCAM‐1) and intercellular adhesion molecule‐1 (ICAM‐1) were shown. With the presence of G‐Rb1, decreased levels of PI3K/Akt, phosphorylated IκBα and p65 were also observed. Furthermore, phosphorylated ERK and JNK by LPS were diminished within 15, 30 and 60 min of G‐Rb1 exposure; however, the expression of non‐phosphorylated ERK and JNK remained unchanged. Conclusions: G‐Rb1 suppressed the LPS‐induced increase of cell adhesion molecules and inflammatory cytokines, while also inhibiting PI3K/Akt, phosphorylation of NF–κB transcription factors, ERK and JNK of MAPK signalling in hDPCs. [ABSTRACT FROM AUTHOR]

Several members of the transforming growth factor beta (TGF‐β) superfamily regulate the proliferation, differentiation, and function of bone‐forming osteoblasts and bone‐resorbing osteoclasts. However, it is still unknown whether Nodal, a member of the TGF‐β superfamily, serves a function in bone cells. In this study, we found that Nodal did not have any function in osteoblasts but instead negatively regulated osteoclast differentiation. Nodal inhibited RANKL‐induced osteoclast differentiation by downregulating the expression of pro‐osteoclastogenic genes, including c‐fos, Nfatc1, and Blimp1, and upregulating the expression of antiosteoclastogenic genes, including Bcl6 and Irf8. Nodal activated STAT1 in osteoclast precursor cells, and STAT1 downregulation significantly reduced the inhibitory effect of Nodal on osteoclast differentiation. These findings indicate that Nodal activates STAT1 to downregulate or upregulate the expression of pro‐osteoclastogenic or antiosteoclastogenic genes, respectively, leading to the inhibition of osteoclast differentiation. Moreover, the inhibitory effect of Nodal on osteoclast differentiation contributed to the reduction of RANKL‐induced bone loss in vivo. [ABSTRACT FROM AUTHOR]

Human monocyte chemoattractant protein‐1 (MCP‐1) in mice has two orthologs, MCP‐1 and MCP‐5. MCP‐1, which is highly expressed in osteoclasts rather than in osteoclast precursor cells, is an important factor in osteoclast differentiation. However, the roles of MCP‐5 in osteoclasts are completely unknown. In this study, contrary to MCP‐1, MCP‐5 was downregulated during receptor activator of nuclear factor kappa B ligand (RANKL)‐induced osteoclast differentiation and was considered an inhibitory factor in osteoclast differentiation. The inhibitory role of MCP‐5 in osteoclast differentiation was closely related to the increase in Ccr5 expression and the inhibition of IκB degradation by RANKL. Transgenic mice expressing MCP‐5 controlled by Mx‐1 promoter exhibited an increased bone mass because of a decrease in osteoclasts. This result strongly supported that MCP‐5 negatively regulated osteoclast differentiation. MCP‐5 also prevented severe bone loss caused by RANKL. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association between obesity and self‐rated oral health (SROH). This study examined the cross‐sectional associations between body mass index (BMI) and SROH in Korean adults. Materials and methods: This study used data from 217 304 adults (100 110 men and 117 194 women aged > 19 years) from the 2017 Korean Community Health Survey. Participants were categorised into six ordinal groups based on BMI: underweight (<18.5 kg/m2), normal weight (18.5‐22.9 kg/m2), overweight (23.0‐24.9 kg/m2), obese‐I (25.0‐27.4 kg/m2), obese‐II (27.5‐29.9 kg/m2) or obese‐III (≥30.0 kg/m2). SROH was assessed using responses to the question, "How do you rate your oral health, including your teeth and gums?" rated on a 5‐point scale. SROH was categorised as "good" (reported as "fair," "good" or "very good") or "poor" or "very poor." Age‐ and sex‐stratified associations between BMI categories and poor SROH were assessed using ordinal logistic regression analysis with sampling weights. Results: The age‐adjusted odds ratio (OR) for poor SROH according to BMI levels was lowest in the overweight group in both men and women. In men, the OR for poor SROH was 2.03 (99% confidence interval [CI], 1.72‐2.39) in the underweight group, 1.17 (99% CI, 1.17‐1.25) in the normal group, 1.05 (99% CI, 0.98‐1.13) in the obese‐I group, 1.08 (99% CI, 0.98‐1.18) in the obese‐II group and 1.36 (99% CI, 1.20‐1.55) in the obese‐III group. In women, the OR was 1.18 (99% CI, 1.07‐1.31) in the underweight group, 1.01 (99% CI, 0.95‐1.07) in the normal group, 1.07(99% CI, 0.99‐1.16) in the obese‐I group, 1.16 (99% CI, 1.04‐1.30) in the obese‐II group and 1.39 (99% CI, 1.20‐1.62) in the obese‐III group. From the restricted cubic spline models in both sexes, BMI showed a J‐shaped association with poor and very poor SROH in men and women. In a stratified analysis by age group and sex, men and older women in the underweight group had poorer SROH than those in overweight group. Conclusion: In a nationally representative sample of Korean adults, there was a J‐shaped association between BMI and poor SROH, with the highest risk in the underweight group amongst men and in the obese‐III group amongst women. Furthermore, in men and women over 65 years of age, underweight and obesity were associated with poorer SROH. [ABSTRACT FROM AUTHOR]

The engulfment adaptor phosphotyrosine‐binding domain containing 1 (GULP1) is an adaptor protein involved in the engulfment of apoptotic cells via phagocytosis. Gulp1 was first found to promote the phagocytosis of apoptotic cells by macrophages, and its role in various tissues, including neurons and ovaries, has been well studied. However, the expression and function of GULP1 in bone tissue are poorly understood. Consequently, to determine whether GULP1 plays a role in the regulation of bone remodeling in vitro and in vivo, we generated Gulp1 knockout (KO) mice. Gulp1 was expressed in bone tissue, mainly in osteoblasts, while its expression is very low in osteoclasts. Microcomputed tomography and histomorphometry analysis in 8‐week‐old male Gulp1 KO mice revealed a high bone mass in comparison with male wild‐type (WT) mice. This was a result of decreased osteoclast differentiation and function in vivo and in vitro as confirmed by a reduced actin ring and microtubule formation in osteoclasts. Gas chromatography‐mass spectrometry analysis further showed that both 17β‐estradiol (E2) and 2‐hydroxyestradiol levels, and the E2/testosterone metabolic ratio, reflecting aromatase activity, were also higher in the bone marrow of male Gulp1 KO mice than in male WT mice. Consistent with mass spectrometry analysis, aromatase enzymatic activity was significantly higher in the bone marrow of male Gulp1 KO mice. Altogether, our results suggest that GULP1 deficiency decreases the differentiation and function of osteoclasts themselves and increases sex steroid hormone‐mediated inhibition of osteoclast differentiation and function, rather than affecting osteoblasts, resulting in a high bone mass in male mice. To the best of our knowledge, this is the first study to explore the direct and indirect roles of GULP1 in bone remodeling, providing new insights into its regulation. [ABSTRACT FROM AUTHOR]

Aim: To study the role of sclerostin in periodontal ligament (PDL) as a homeostatic regulator in biophysical‐force‐induced tooth movement (BFTM). Materials and Methods: BFTM was performed in rats, followed by microarray, immunofluorescence, in situ hybridization, and real‐time polymerase chain reaction for the detection and identification of the molecules. The periodontal space was analysed via micro‐computed tomography. Effects on osteoclastogenesis and bone resorption were evaluated in the bone‐marrow‐derived cells in mice. In vitro human PDL cells were subjected to biophysical forces. Results: In the absence of BFTM, sclerostin was hardly detected in the periodontium except in the PDL and alveolar bone in the furcation region and apex of the molar roots. However, sclerostin was up‐regulated in the PDL in vivo by adaptable force, which induced typical transfiguration without changes in periodontal space as well as in vitro PDL cells under compression and tension. In contrast, the sclerostin level was unaffected by heavy force, which caused severe degeneration of the PDL and narrowed periodontal space. Sclerostin inhibited osteoclastogenesis and bone resorption, which corroborates the accelerated tooth movement by the heavy force. Conclusions: Sclerostin in PDL may be a key homeostatic molecule in the periodontium and a biological target for the therapeutic modulation of BFTM. [ABSTRACT FROM AUTHOR]

Aim: Mucosal‐associated invariant T (MAIT) cells are known to be resident in oral mucosal tissue, but their roles in periodontitis are unknown. This study aimed to examine the level and function of MAIT cells in periodontitis patients. Materials and Methods: Frequency, activation, and function of MAIT cells from 28 periodontitis patients and 28 healthy controls (HCs) were measured by flow cytometry. Results: Circulating MAIT cells were numerically reduced in periodontitis patients. Moreover, they exhibited higher expression of CD69 and annexin V, together with more increased production of interleukin (IL)‐17 and tumour necrosis factor (TNF)‐α, in periodontitis patients than in HCs. Interestingly, periodontitis patients had higher frequencies of MAIT cells in gingival tissue than in peripheral blood. In addition, circulating MAIT cells had elevated expression of tissue‐homing chemokine receptors such as CCR6 and CXCR6, and the corresponding chemokines (i.e., CCL20 and CXCL16) were more strongly expressed in inflamed gingiva than in healthy gingiva. Conclusions: This study demonstrates that circulating MAIT cells are numerically deficient with an activated profile toward the production of IL‐17 and TNF‐α in periodontitis patients. Furthermore, circulating MAIT cells have the potential to migrate to inflamed gingival tissues. [ABSTRACT FROM AUTHOR]

Aim: We aimed to identify a key molecule that maintains periodontal tissue homeostasis during biophysical force‐induced tooth movement (BTM) by orchestrating alveolar bone (AB) remodelling. Materials and Methods: Differential display‐PCR was performed to identify key molecules for BTM in rats. To investigate the localization and expression of the identified molecules, immunofluorescence, real‐time RT‐PCR and Western blotting were performed in rats and human periodontal ligament (PDL) cells. Functional test and micro‐CT analysis were performed to examine the in vivo effects of the identified molecules on BTM. Results: Secretory leucocyte peptidase inhibitor (SLPI) in the PDL was revealed as a key molecule for BTM‐induced AB remodelling. SLPI was enhanced in the PDL under both compression and tension, and downregulated by an adenyl cyclases inhibitor. SLPI induced osteoblastogenic genes including runt‐related transcription factor 2 (Runx2) and synergistically augmented tension‐induced Runx2 expression. SLPI augmented mineralization in PDL cells. SLPI induced osteoclastogenic genes including receptor activator of nuclear factor kappa‐Β ligand (RANKL) and synergistically augmented the compression‐induced RANKL and macrophage colony‐stimulating factor (MCSF) expression. Finally, the in vivo SLPI application into the AB significantly augmented BTM. Conclusions: SLPI or its inhibitors might serve as a biological target molecule for therapeutic interventions to modulate BTM. [ABSTRACT FROM AUTHOR]

Background: The association between diabetes mellitus (DM) and bone diseases is acknowledged. However, the mechanistic pathways leading to the alveolar bone (AB) destruction remain unclear. This study aims to elucidate the mechanical forces (MF)-induced AB destruction in DM and its underlying mechanism.Methods: In vivo periodontal tissue responses to MF were evaluated in rats with diabetes. In vitro human periodontal ligament (PDL) cells were either treated with advanced glycation end products (AGEs) alone or with AGEs and MF.Results: In vivo, the transcription of VEGF-A, colony stimulating factor-1 (CSF-1), and Ager was upregulated in diabetes, whereas changes in DDOST and Glo1 mRNAs were negligible. DM induced VEGF-A protein in the vascular cells of the PDL and subsequent angiogenesis, but DM itself did not induce osteoclastogenesis. MF-induced AB resorption was augmented in DM, and such augmentation was morphologically substantiated by the occasional undermining resorption as well as the frontal resorption of the AB by osteoclasts. The mRNA levels of CSF-1 and vascular endothelial growth factor (VEGF) during MF application were highly elevated in diabetes, compared with those of the normal counterparts. In vitro, AGEs treatment elevated Glut-1 and CSF-1 mRNA levels via the p38 and JNK pathways, whereas OGT and VEGF levels remained unchanged. Compressive MF especially caused upregulation of VEGF, CSF-1, and Glut-1 levels, and such upregulation was further enhanced by AGEs treatment.Conclusions: Overloaded MF and AGEs metabolites may synergistically aggravate AB destruction by upregulating CSF-1 and VEGF. Therefore, regulating the compressive overloading of teeth, as well as the levels of diabetic AGEs, may prove to be an effective therapeutic modality for managing DM-induced AB destruction. [ABSTRACT FROM AUTHOR]

Differentiated ameloblasts secret enamel matrix proteins such as amelogenin, ameloblastin, and enamelin. Expression levels of these proteins are regulated by various factors. To find a new regulatory factor for ameloblast differentiation, we performed 2D-PAGE analysis using mouse ameloblast lineage cell line (mALCs) cultured with mineralizing medium. Of identified proteins, family with sequence similarity 50 member A (Fam50a) was significantly increased during differentiation of mALCs. Fam50a protein was also highly expressed in secretory ameloblasts of mouse tooth germs. In mALCs cultures, forced expression of Fam50a up-regulated the expression of enamel matrix protein genes such as amelogenin, ameloblastin, and enamelin. In addition, up-regulation of Fam50a also increased ALP activity and mineralized nodule formation in a dose-dependent manner. In contrast, knockdown of Fam50a decreased expression levels of enamel matrix protein genes, ALP activity, and mineralized nodule formation. By fluorescence microscopy, endogenous Fam50a protein was found to be localized to the nucleus of ameloblasts. In addition, Fam50a synergistically increased Ambn transactivation by Runx2. Moreover, Fam50a increased binding affinity of Runx2 to Ambn promoter by physically interacting with Runx2. Taken together, these results suggest Fam50a might be a new positive regulator of ameloblast differentiation. [ABSTRACT FROM AUTHOR]

An injectable hydrogel system with sustained bone morphogenetic protein 2 (BMP-2) release ability was developed for vertical bone regeneration at peri-implant sites and enhanced osseointegration of dental implants. In three young male beagle dogs, a pair of defects was created on both sides of the mandibular bone. Next, two implants were transplanted into each defect. In situ gelling polymer solutions with or without BMP-2 were applied to cover the implants and mandibular defects. The effects of the in situ gelling and sustained BMP-2 releasing (IGSR) hydrogel system on peri-implant bone regeneration were evaluated by radiologic examination, micro-computed tomography, and histomorphometric analysis. Twelve weeks after the treatment, significant bone generation at the peri-implant site occurred following BMP-2/IGSR hydrogel treatment. Bone volume and mineral density were increased by 1.7- and 1.3-fold, respectively ( p < 0.01 and 0.05 vs. control, respectively) for the BMP-2/IGSR hydrogel system. And, 0.57-0.31 mm vertical bone generation was observed at the peri-implant site for the BMP-2/IGSR hydrogel system, while rare vertical bone generation occurred in the control group. The BMP-2/IGSR hydrogel system significantly increased bone to implant contact % between induced bone and existing bone ( p < 0.05 and 0.01 vs. control). These vertical bone regeneration and higher osseointegration levels demonstrated the effectiveness of the BMP-2/IGSR hydrogel system. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 751-759, 2018. [ABSTRACT FROM AUTHOR]

Treatment of acute myeloid leukemia (AML) largely depends on chemotherapy, but current regimens have been unsatisfactory for long-term remission. Although differentiation induction therapy utilizing 1,25(OH)2D3 (VD3) has shown great promise for the improvement of AML treatment efficacy, severe side effects caused by its supraphysiological dose limit its clinical application. Here we investigated the combinatorial effect of l-asparaginase (ASNase)-mediated amino acid depletion and the latent alternation of VD3 activity on the induction of myeloid differentiation. ASNase treatment enhanced VD3-driven phenotypic and functional differentiation of three-different AML cell lines into monocyte/macrophages, along with c-Myc downregulation. Using gene silencing with shRNA and a chemical blocker, we found that reduced c-Myc is a critical factor for improving VD3 efficacy. c-Myc-dependent inhibition of mTORC1 signaling and induction of autophagy were involved in the enhanced AML cell differentiation. In addition, in a postculture of AML cells after each treatment, ASNase supports the antileukemic effect of VD3 by inhibiting cell growth and inducing apoptosis. Finally, we confirmed that the administration of ASNase significantly improved VD3 efficacy in the prolongation of survival time in mice bearing tumor xenograft. Our results are the first to demonstrate the extended application of ASNase, which is currently used for acute lymphoid leukemia, in VD3-mediated differentiation induction therapy for AML, and suggest that this drug combination may be a promising novel strategy for curing AML. [ABSTRACT FROM AUTHOR]

Objective. To investigate the role played by natural killer T (NKT) cells in osteoclastogenesis and their effects on inflammatory bone destruction. Methods. Patients with rheumatoid arthritis (RA) (n = 25) and healthy controls (n = 12) were enrolled in this study. In vitro osteoclastogenesis experiments were performed using peripheral blood mononuclear cells (PBMCs) in the presence of macrophage colony-stimulating factor and RANKL. PBMCs were cultured in vitro with α-galactosylceramide (αGalCer), and proliferation indices of NKT cells were estimated by flow cytometry. In vivo effects of αGalCer-stimulated NKT cells on inflammation and bone destruction were determined in mice with collagen-induced arthritis. Results. In vitro osteoclastogenesis was found to be significantly inhibited by αGalCer in healthy controls but not in RA patients. Proliferative responses of NKT cells and STAT-1 phosphorylation in monocytes in response to αGalCer were impaired in RA patients. Notably, αGalCer-stimulated NKT cells inhibited osteoclastogenesis mainly via interferon-γ production in a cytokine-dependent manner (not by cell–cell contact) and down-regulated osteoclast-associated genes. Mice treated with αGalCer showed less severe arthritis and reduced bone destruction. Moreover, proinflammatory cytokine expression in arthritic joints was found to be reduced by αGalCer treatment. Conclusion. This study primarily demonstrates that αGalCer-stimulated NKT cells have a regulatory effect on osteoclastogenesis and a protective effect against inflammatory bone destruction. However, it also shows that these effects of αGalCer are diminished in RA patients and that this is related to NKT cell dysfunction. These findings provide important information for those searching for novel therapeutic strategies to prevent bone destruction in RA. [ABSTRACT FROM AUTHOR]

Chicken ovalbumin upstream promoter transcription factor II (COUP-TFII) is a potent transcription factor that represses osteoblast differentiation and bone formation. Previously, we observed that stimuli for osteoblast differentiation, such as bone morphogenetic protein 2 (BMP2), inhibits COUP-TFII expression. This study was undertaken to identify BMP2-regulated and COUP-TFII-targeting microRNAs (miRNAs), and to explore their regulatory roles in osteoblast differentiation. Based on in silico analysis, 12 miRNAs were selected and their expression in BMP2-treated MC3T3-E1 cells was examined. BMP2 induced miR-302a expression in dose- and time-dependent manners with the decrease in COUP-TFII expression. Runx2, a BMP2-downstream transcription factor, specifically regulated miR-302a expression and its promoter activity. A computer-based prediction algorithm led to the identification of two miR-302a binding sites on the 3′-untranslational region of COUP-TFII mRNA (S1: 620-626 bp, S2: 1,016-1,022 bp), and a luciferase assay showed that miR-302a directly targeted S1 and S2. Transfection of miR-302a precursor significantly enhanced expression of osteogenic marker genes with decreasing COUP-TFII mRNA and protein level, alkaline phosphatase activity and matrix mineralization. On the other hand, inhibition of miR-302a significantly attenuated BMP2-induced osteoblast specific gene expression, alkaline phosphatase activity, and matrix mineralization with increasing COUP-TFII mRNA and protein level. These results indicate that miR-302a is induced by osteogenic stimuli and promotes osteoblast differentiation by targeting COUP-TFII. MiR-302a could be a positive regulator for osteoblast differentiation. J. Cell. Physiol. 230: 911-921, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The present study explored the involvement of miR-302a in adipocyte differentiation via interaction with 3′-untranslated region of peroxisome proliferator-activated receptor gamma (PPARγ) mRNA. In differentiating 3T3-L1 adipocytes, expression of miR-302a was negatively correlated with that of the adipogenic gene aP2 and PPARγ. Overexpression of miR-302a inhibited adipogenic differentiation with lipid accumulation, and inversely anti-miR-302a increased the differentiation. In silico analysis revealed a complementary region of miR-302a seed sequence in 3′-UTR of PPARγ mRNA. Luciferase assay showed the direct interaction of miR-302a with PPARγ at the cellular level. The miR-302a inhibition of adipocyte differentiation was reversed by PPARγ overexpression. These findings suggest that miR-302a might be a negative regulator of adipocyte differentiation and that the dysregulation of miR-302a should lead to metabolic disorders. [ABSTRACT FROM AUTHOR]

Implant failure has been attributed to loosening of an implant from the host bone possibly due to poor osseointegration. One promising strategy for improving osseointegration is to develop a functional implant surface that promotes osteoblast differentiation. In this study, a titanium (Ti) surface was functionalized by an anodic oxidation process and was loaded with recombinant human bone morphogenetic protein‐2 (rhBMP‐2). The following four groups of Ti surfaces were prepared: machined (M), anodized machined (MA), resorbable blast medium (RBM), and anodized RBM (RBMA). The surfaces were characterized by scanning electron microscopy and contact angle measurements. The results showed that a Ti oxide layer (TiO2) was observed in the anodized surfaces in the form of nanotubes, ∼100 nm in diameter and 500 nm in length. The hydrophilic properties of the anodized surfaces were significantly improved. The adsorbed rhBMP‐2 loaded on the nonanodized surfaces and lyophilized showed spherical particle morphology. However, the adsorbed rhBMP‐2 showed a dispersed pattern over the anodized surfaces. The velocity of the rhBMP‐2 released from the surfaces was measured to determine if the anodized surface can improve in delivery efficiency. The results showed that the release velocity of the rhBMP‐2 from the anodized surfaces was sustained when compared with that of the nonanodized surfaces. In addition, the rhBMP‐2 released from the surface was found to be bioactive according to the alkaline phosphatase activity and the level of calcium mineral deposition. These results suggest that the TiO2 nanotubular structure formed by anodizing is a promising configuration for sustained rhBMP‐2 delivery. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010 [ABSTRACT FROM AUTHOR]

The purpose of this study was to fabricate and characterize nanotubular structure on machined titanium (MA) and resorbable blast media (RBM) treated titanium by anodizing. The anodized MA and RBM were characterized with scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, energy disperse spectra, X‐ray photoelectron spectra, and nano‐indentation and scratch test. Highly ordered nanotubular layers of individually 100 nm in diameter and 500 nm in length approximately were formed regardless of the substrates. The nanotubular layers consisted mainly of amorphous TiO2 with trace fluorine. The nanotubular surfaces on both the substrates significantly reduced water contact angles and elastic modulus compared with those prior to anodizing. The anodizing treatment significantly increased the surface roughness of the smooth MA, but significantly decreased the surface roughness of the roughened RBM. The critical delamination forces of the nanotubular layer were not obtained due to the limitation of surface roughness. The anodized RBM consisted of a nano‐micro porous graded structure, or a nanotubular amorphous fluoride containing TiO2 layer on top of micro‐roughened titanium surface, which is expected to significantly improve the surface area that can be used to deliver drugs and growth factors and alleviate the interfacial elastic modulus mismatch as to enhance osseointegration when compared with conventional dental and orthopedic implant devices with smooth or acid etched surface. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009 [ABSTRACT FROM AUTHOR]

Restricting transgene expression to specific cell types and maintaining long-term expression are major goals for gene therapy. Previously, we cloned brain-specific angiogenesis inhibitor 1-associated protein 4 (BAI1-AP4), a novel brain-specific protein that interacts with BAI1, and found that it was developmentally upregulated in the adult brain. In this report, we isolated 5 kb of the 5′ upstream sequence of the mouse BAI1-AP4 gene and analyzed its promoter activity. Functional analyses demonstrated that an Sp1 site was the enhancer, and the region containing the transcription initiation site and an AP2-binding site was the basal promoter. We examined the ability of the BAI1-AP4 promoter to drive adult brain-specific expression by using it to drive lacZ expression in transgenic (TG) mice. Northern blot analyses showed a unique pattern of β-galactosidase expression in TG brain, peaking at 1 month after birth, like endogenous BAI1-AP4. Histological analyses demonstrated the same localization and developmental expression of β-galactosidase and BAI1-AP4 in most neurons of the cerebral cortex and hippocampus. Our data indicate that TG mice carrying the BAI1-AP4 promoter could be a valuable model system for region-specific brain diseases. [Copyright &y& Elsevier]

Koh JT, Kim OJ, Park YS, Kim SH, Kim WJ, Chung HJ, Lee SE, Jeong BC, Jung JY, Kim KK. Decreased expressions of thrombospondin 2 in cyclosporin A-induced gingival overgrowth. J Periodont Res 2004; 39; 93–100. © Blackwell Munksgaard, 2004 Cyclosporin A (CsA) is known to elicit fibrous gingival overgrowth with changes of blood vessel profiles. In this study, we examined the expression of several angiogenic and angiostatic genes during the development of CsA-induced gingival overgrowth. For the development of gingival overgrowth, Sprague-Dawley rats received subcutaneous injections of CsA in daily doses of 5, 10, 15 mg/kg body weight for 6 weeks, and another group received 10 mg/kg of CsA for 3, 6, and 12 weeks . Human gingival tissues were obtained from three CsA-treated patients following the gingivectomy procedure and from three healthy patients following the crown-lengthening procedure as a control. Gingival fibroblasts were isolated from the healthy gingival tissues of the rat or the human, and cultured with 250–1000 ng/ml of CsA. Reverse transcription–polymerase chain reaction (RT–PCR) analyses showed that expressions of some angiogenic genes such as angiopoietin 1, basic fibroblast growth factor, and vascular endothelial growth factor, and angiostatic genes such as angiopoietin 2, brain-specific angiogenesis inhibitor 1 and 2, and thrombospondin 1 were not changed significantly in both gingival tissues and cultured fibroblast cells under the CsA treatments. However, expression of thrombospondin 2 (TSP2) decreased dose- and time-dependently in rat and human gingival tissues. Western blot analyses showed that the expression of TSP2 protein was dose-dependently reduced by the CsA treatments in human cultured gingival fibroblasts. These results indicate that the decrease in angiostatic TSP2 expression may be attributed to the CsA-induced gingival vascularization rather than to the increased expression of angiogenic genes. It suggests that TSP2 is involved in the development of CsA-induced gingival overgrowth with the gingival vascularization. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusion Osteoarthritis (OA) is the most common degenerative disease worldwide, with no practical means of prevention and limited treatment options. Recently, our group unveiled a novel mechanism contributing to OA pathogenesis in association with abnormal cholesterol metabolism in chondrocytes. In this study, we aimed to establish a clinical link between lipid profiles and OA in humans, assess the effectiveness of cholesterol‐lowering drugs in suppressing OA development in mice, and uncover the cholesterol‐lowering mechanisms that effectively impede OA progression.Five clinically approved cholesterol‐lowering drugs (fenofibrate, atorvastatin, ezetimibe, niacin, and lomitapide) were injected into the knee joints or administered with diet to mice with OA who underwent destabilization of the medial meniscus induction and were fed a 2% high‐cholesterol diet. Gene expression linked to cholesterol metabolism was determined using microarray analysis. Furthermore, the in vivo functions of these genes were explored through intra‐articular injection of either its inhibitor or adenovirus.Logistic regression analysis confirmed a close relationship between the diagnostic criteria of hyperlipidemia based on serum lipid levels and OA incidence. Among the cholesterol‐lowering drugs examined, fenofibrate exerted the most significant protective effect against cartilage destruction, which was attributed to elevated levels of high‐density lipoprotein cholesterol that are crucial for cholesterol efflux. Notably, cholesterol efflux was suppressed during OA progression via down‐regulation of apolipoprotein A1–binding protein (AIBP) expression. Overexpression of AIBP effectively inhibits OA progression.Our results suggest that restoration of cholesterol homeostasis to a normal state through administration of fenofibrate or AIBP overexpression, both of which induce cholesterol efflux, offers an effective therapeutic option for patients with OA. [ABSTRACT FROM AUTHOR]