Calcium-sensing receptor-ERK signaling promotes odontoblastic differentiation of human dental pulp cells

Activation of the G protein-coupled calcium-sensing receptor (CaSR) has crucial roles in skeletal development and bone turnover. Our recent study has identified a role for activated CaSR in the osteogenic differentiation of human periodontal ligament stem cells. Furthermore, odontoblasts residing inside the tooth pulp chamber play a central role in dentin formation. However, it remains unclear how CaSR activation affects the odontoblastic differentiation of human dental pulp cells (HDPCs). We have investigated the odontoblastic differentiation of HDPCs exposed to elevated levels of extracellular calcium (Ca) and strontium (Sr), and the contribution of CaSR and the L-type voltage-dependent calcium channel (L-VDCC) to this process. Immunochemical staining of rat dental pulp tissue demonstrated that CaSR was expressed at high levels in the odontoblastic layer, moderate levels in the sublayer, and low levels in the central pulp tissue. Although normal HDPCs expressed low levels of CaSR, stimulation with Ca or Sr promoted both CaSR expression and odontoblastic differentiation of HDPCs along with increased expression of odontoblastic makers. These effects were inhibited by treatment with a CaSR antagonist, whereas treatment with an L-VDCC inhibitor had no effect. Additionally, knockdown of CaSR with siRNA suppressed odontoblastic differentiation of Ca- and Sr-treated HDPCs. ERK1/2 phosphorylation was observed in Ca- and Sr-treated HDPCs, whereas CaSR antagonist treatment or CaSR knockdown blocked ERK1/2 phosphorylation. Furthermore, inhibition of ERK1/2 suppressed mineralization of Ca- and Sr-treated HDPCs. These results suggest that elevated concentrations of extracellular Ca and Sr induce odontoblastic differentiation of HDPCs through CaSR activation and the ERK1/2 phosphorylation.

Transgelin mediates transforming growth factor-β1-induced proliferation of human periodontal ligament cells

BACKGROUND AND OBJECTIVE

Human periodontal ligament cells (HPDLCs) express transforming growth factor-β1 (TGF-β1) that regulates differentiation and proliferation, and plays key roles in homeostasis of PDL tissue. Transgelin is a cytoskeleton-associated protein with an Smad-binding element in its gene promoter region. In this study, we examined the localization and potential function of transgelin in PDL tissue and cells.

MATERIAL AND METHODS

Microarray analysis of HPDLC lines (2-14, 2-23 and 2-52) was performed. Expression of transgelin in HPDLCs was examined by quantitative reverse transcription-polymerase chain reaction, immunofluorescence staining and western blot analysis. Effects of TGF-β1 and its signaling inhibitor, SB431542, on transgelin expression in HPDLCs were examined by western blot analysis. The effects of transgelin knockdown by small interfering RNA (siRNA) on HPDLC proliferation stimulated by TGF-β1 were assessed by WST-1 assay.

RESULTS

In microarray and quantitative reverse transcription-polymerase chain reaction analyses, the expression levels of transgelin (TAGLN) in 2-14 and 2-23 cells, which highly expressed PDL markers such as periostin (POSTN), tissue non-specific alkaline phosphatase (ALPL), α-smooth muscle actin (ACTA2) and type I collagen A1 (COL1A1), was significantly higher than those in 2-52 cells that expressed PDL markers weakly. Immunohistochemical and immunofluorescence staining revealed expression of transgelin in rat PDL tissue and HPDLCs. In HPDLCs, TGF-β1 treatment upregulated transgelin expression, whereas inhibition of the type 1 TGF-β1 receptor by SB431542 suppressed this upregulation. Furthermore, TAGLN siRNA transfection did not promote the proliferation of HPDLCs treated with TGF-β1. The expression levels of CCNA2 and CCNE1, which regulate DNA synthesis and mitosis through the cell cycle, were also not upregulated in HPDLCs transfected with TAGLN siRNA.

CONCLUSION

Transgelin is expressed in PDL tissue and might have a role in HPDLC proliferation induced by TGF-β1 stimulation.

Transforming growth factor-β-induced gene product-h3 inhibits odontoblastic differentiation of dental pulp cells

OBJECTIVE

The aim of this study was to investigate transforming growth factor-β-induced gene product-h3 (βig-h3) expression in dental pulp tissue and its effects on odontoblastic differentiation of dental pulp cells (DPCs).

DESIGN

A rat direct pulp capping model was prepared using perforated rat upper first molars capped with mineral trioxide aggregate cement. Human DPCs (HDPCs) were isolated from extracted teeth. βig-h3 expression in rat dental pulp tissue and HDPCs was assessed by immunostaining. Mineralization of HDPCs was assessed by Alizarin red-S staining. Odontoblast-related gene expression in HDPCs was analyzed by quantitative RT-PCR.

RESULTS

Expression of βig-h3 was detected in rat dental pulp tissue, and attenuated by direct pulp capping, while expression of interleukin-1β and tumor necrosis factor-α was increased in exposed pulp tissue. βig-h3 expression was also detected in HDPCs, with reduced expression during odontoblastic differentiation. The above cytokines reduced βig-h3 expression in HDPCs, and promoted their mineralization. Recombinant βig-h3 inhibited the expression of odontoblast-related genes and mineralization of HDPCs, while knockdown of βig-h3 gene expression promoted the expression of odontoblast-related genes in HDPCs.

CONCLUSIONS

The present findings suggest that βig-h3 in DPCs may be involved in reparative dentin formation and that its expression is likely to negatively regulate this process.

Digital Subtraction Angiography in Takayasu Arteritis

The usefulness and limitation of digital subtraction angiography (DSA) in Takayasu arteritis were investigated in 32 patients. Intravenous DSA was particularly useful in the follow-up of patients with an established diagnosis of Takayasu arteritis. Pulmonary arterial involvement could also be demonstrated with intravenous DSA as obstructive arterial changes and lack of accumulation of contrast medium in the pulmonary parenchyma. Detailed information concerning the site and extent of vascular involvement and development of collateral vessels were obtained with intraarterial DSA. Thickening of the thoracic aortic wall, however, could not be recognized with either intravenous or intraarterial DSA. Conventional angiography of the descending thoracic aorta is still required as an initial examination, particularly when there is no aortic arch involvement. However, there is no doubt that DSA has the potential to become the diagnostic procedure of choice in Takayasu arteritis.

Paravertebral Arteriovenous Malformation with Venous Connection to Left Iliac Vein

An unusual systemic arteriovenous malformation arising from the left 9th intercostal artery, taking a caudal course through the left paravertebral veins, eventually drained into the left ascending lumbar vein, as illustrated at computed tomography and angiography. An embryologic maldevelopment of the azygos venous system is not the only possible explanation for venous drainage in the caudal direction. We believe that predominant venous drainage can take place in either direction because of the potentially bidirectional flow in the vertebral venous systems.

GDNF From Human Periodontal Ligament Cells Treated With Pro-Inflammatory Cytokines Promotes Neurocytic Differentiation of PC12 Cells

Glial cell line-derived neurotrophic factor (GDNF) is known to mediate multiple biological activities such as promotion of cell motility and proliferation, and morphogenesis. However, little is known about its effects on periodontal ligament (PDL) cells. Recently, we reported that GDNF expression is increased in wounded rat PDL tissue and human PDL cells (HPDLCs) treated with pro-inflammatory cytokines. Here, we investigated the associated expression of GDNF and the pro-inflammatory cytokine interleukin-1 beta (IL-1β) in wounded PDL tissue, and whether HPDLCs secrete GDNF which affects neurocytic differentiation. Rat PDL cells near the wounded area showed intense immunoreactions against an anti-GDNF antibody, where immunoreactivity was also increased against an anti-IL-1β antibody. Compared with untreated cells, HPDLCs treated with IL-1β or tumor necrosis factor-alpha showed an increase in the secretion of GDNF protein. Conditioned medium of IL-1β-treated HPDLCs (IL-1β-CM) increased neurite outgrowth of PC12 rat adrenal pheochromocytoma cells. The expression levels of two neural regeneration-associated genes, growth-associated protein-43 (Gap-43), and small proline-rich repeat protein 1A (Sprr1A), were also upregulated in IL-1β-CM-treated PC12 cells. These stimulatory effects of IL-1β-CM were significantly inhibited by a neutralizing antibody against GDNF. In addition, U0126, a MEK inhibitor, inhibited GDNF-induced neurite outgrowth of PC12 cells. These findings suggest that an increase of GDNF in wounded PDL tissue might play an important role in neural regeneration probably via the MEK/ERK signaling pathway. J. Cell. Biochem. 118: 699-708, 2017. © 2016 Wiley Periodicals, Inc.

Semaphorin 3A Induces Odontoblastic Phenotype in Dental Pulp Stem Cells

In cases of pulp exposure due to deep dental caries or severe traumatic injuries, existing pulp-capping materials have a limited ability to reconstruct dentin-pulp complexes and can result in pulpectomy because of their low potentials to accelerate dental pulp cell activities, such as migration, proliferation, and differentiation. Therefore, the development of more effective therapeutic agents has been anticipated for direct pulp capping. Dental pulp tissues are enriched with dental pulp stem cells (DPSCs). Here, the authors investigated the effects of semaphorin 3A (Sema3A) on various functions of human DPSCs in vitro and reparative dentin formation in vivo in a rat dental pulp exposure model. Immunofluorescence staining revealed expression of Sema3A and its receptor Nrp1 (neuropilin 1) in rat dental pulp tissue and human DPSC clones. Sema3A induced cell migration, chemotaxis, proliferation, and odontoblastic differentiation of DPSC clones. In addition, Sema3A treatment of DPSC clones increased β-catenin nuclear accumulation, upregulated expression of the FARP2 gene (FERM, RhoGEF, and pleckstrin domain protein 2), and activated Rac1 in DPSC clones. Furthermore, in the rat dental pulp exposure model, Sema3A promoted reparative dentin formation with dentin tubules and a well-aligned odontoblast-like cell layer at the dental pulp exposure site and with novel reparative dentin almost completely covering pulp tissue at 4 wk after direct pulp capping. These findings suggest that Sema3A could play an important role in dentin regeneration via canonical Wnt/β-catenin signaling. Sema3A might be an alternative agent for direct pulp capping, which requires further study.

Effects of therapeutic agents on cellular respiration as an indication of metabolic activity

Animal experiments are indispensable in the investigation of the toxicity of drugs on cells, but may not be preferred for ethical reasons and sensitivity. As an alternative procedure, we investigated the susceptibility of cells to drugs using the effect on cellular respiration as an indicator of cell activity (toxicity). The primary cultures (cell lines) used in this study included human fetal myocardial cells, skeletal muscle cells, nerve cells, hypophyseal cells, epithelial cells of gastric mucosa, lymphocytes, hepatocytes, pancreatic (exocrine) cells, renal tubular epithelial cells and fetal adrenal cortex cells, which were obtained from the American Type Culture Collection (ATCC). The drugs used were diazepam, haloperidol and levomepromazine maleate (psychoactive drugs), cisplatin and doxorubicin hydrochloride (anticancer agents). The cells were used at a density of 2–106 cells/2 mL of growth medium and, to test the susceptibility, each drug was prepared at a concentration of 10 g/mL. Experiment results indicated that, even with the same drug, sensitivity was markedly different depending on the cell lines. Cardiac muscle cells showed the strongest respiratory inhibition by Serenace and were least inhibited by Hirnamin. The highest sensitivity to Cercine was noted for neurons, while gastric mucosa cells had almost no sensitivity. Sensitivity to Serenace, which was expected to have a strong nerve action, was higher in myocardial cells instead. In the present study, we suggested the possibility of studying individual differences in drug sensitivity through investigation of toxicity in each organ as opposed to toxicity in the individual. In addition, Serenace, which was developed as a neurotopic agent, showed a higher toxicity in cardiac muscle cells than in neurons. This finding appeared noteworthy, not only for forensic toxicology, but also for clinical practice and drug development.

Spontaneous Osteosarcoma in a Rabbit (Oryctolagus cuniculus)

A 6-year-old male cross-breed rabbit ( Oryctolagus cuniculus) was presented with lameness and severe swelling from the right shoulder to brachium. On 16-detector helical computed tomography images of the amputated right forelimb after being fixed in formalin, evident proliferative and destructive lesions of bone were observed. On histologic examination, the tumor was composed of proliferating neoplastic cells that resembled histiocytes, with abundant osteoid production. A large number of multinucleated giant cells were found throughout. This case was diagnosed as osteosarcoma by clinical, radiographic, and histologic findings. This is a rare case report of osteosarcoma in a rabbit consistent with canine predilection sites.

Enhanced Anti-tumour Effect of Cisplatin with Low-voltage Electrochemotherapy in Hamster Oral Fibrosarcoma

The aim of this study was to determine the effects of low-voltage electrochemotherapy with intraperitoneal cisplatin on hamster oral fibrosarcoma. Oral fibrosarcoma was transplanted sub-mucosally into the cheek pouch mucosa of 100 hamsters. After transplantation, the hamsters were randomly divided into four equal groups. These groups received no treatment (D-E-); 2 mg/kg body weight cisplatin treatment without electroporation (D+E-); electroporation without cisplatin treatment (D-E+);or 2 mg/kg body weight cisplatin treatment followed by electroporation (D+E+). Electrical pulse treatment together with cisplatin injection markedly reduced the size of the tumour, whereas cisplatin injection or electrical pulse treatment alone did not. These results clearly indicate that the anti-tumour effect of cisplatin on hamster oral fibrosarcoma was considerably potentiated or enhanced by the administration of local electrical pulses at low voltages.

High resolution NMR measurements using a 400MHz NMR with an (RE)Ba2Cu3O7-x high-temperature superconducting inner coil: Towards a compact super-high-field NMR

Use of high-temperature superconducting (HTS) inner coils in combination with conventional low-temperature superconducting (LTS) outer coils for an NMR magnet, i.e. a LTS/HTS NMR magnet, is a suitable option to realize a high-resolution NMR spectrometer with operating frequency >1GHz. From the standpoint of creating a compact magnet, (RE: Rare earth) Ba2Cu3O7-x (REBCO) HTS inner coils which can tolerate a strong hoop stress caused by a Lorentz force are preferred. However, in our previous work on a first-generation 400MHz LTS/REBCO NMR magnet, the NMR resolution and sensitivity were about ten times worse than that of a conventional LTS NMR magnet. The result was caused by a large field inhomogeneity in the REBCO coil itself and the shielding effect of a screening current induced in that coil. In the present paper, we describe the operation of a modified 400MHz LTS/REBCO NMR magnet with an advanced field compensation technology using a combination of novel ferromagnetic shimming and an appropriate procedure for NMR spectrum line shape optimization. We succeeded in obtaining a good NMR line shape and 2D NOESY spectrum for a lysozyme aqueous sample. We believe that this technology is indispensable for the realization of a compact super-high-field high-resolution NMR.

Functional analysis of recombinant 2-Cys peroxiredoxin from the hard tick Haemaphysalis longicornis

Ticks are obligate haematophagous arthropods that feed on vertebrate blood containing high levels of iron. The host-derived iron reacts to oxygen in the tick's body, and then high levels of reactive oxygen species, including hydrogen peroxide (H(2)O(2)), may be generated. High levels of H(2)O(2) cause oxidative stress to aerobic organisms. Therefore, antioxidant responses are necessary to control H(2)O(2). We focused on peroxiredoxins (Prxs), H(2)O(2) -scavenging enzymes. The sequence of Haemaphysalis longicornis 2-Cys Prx (HlPrx2) was identified from fat body cDNA libraries of this tick and recombinant HlPrx2 was then prepared using Escherichia coli. By comparison with the 2-Cys Prxs of other organisms, we found two conserved cysteines in HlPrx2, Cys51 and Cys172. We examined the antioxidant activity of HlPrx2 and mutant proteins produced by a single base substitution, converting one or both of these cysteines into serines. The assays revealed that proteins containing Cys51 showed antioxidant activity when H(2)O(2) was removed. Sodium dodecyl sulphate polyacrylamide gel electrophoresis and size-exclusion chromatography demonstrated that only the wild-type HlPrx2 formed homodimers and that all of the proteins that we made had a high molecular weight peak. These results indicate that both Cys51 and Cys172 are essential for the dimerization of HlPrx2, whereas only the Cys51 residue is necessary for antioxidant activity.

Benzo[a]pyrene/aryl hydrocarbon receptor signaling inhibits osteoblastic differentiation and collagen synthesis of human periodontal ligament cells

BACKGROUND AND OBJECTIVE

Cigarette smoking has detrimental effects on periodontal tissue, and is known to be a risk factor for periodontal disease, including the loss of alveolar bone and ligament tissue. However, the direct effects of cigarette smoking on periodontal tissue remain unclear. Recently, we demonstrated that benzo[a]pyrene (BaP), which is a prototypic member of polycyclic aryl hydrocarbons and forms part of the content of cigarettes, attenuated the expression of extracellular matrix remodeling-related genes in human periodontal ligament (PDL) cells (HPDLCs). Thus, we aimed to examine the effects of BaP on the osteoblastic differentiation and collagen synthesis of HPDLCs.

MATERIAL AND METHODS

HPDLCs were obtained from healthy molars of three patients, and quantitative reverse transcription-polymerase chain reaction were performed for gene expression analyses of cytochrome P450 1A1 and 1B1, alkaline phosphatase, bone sialoprotein and aryl hydrocarbon receptor (AhR), a receptor for polycyclic aryl hydrocarbons. We have also analyzed the role of the AhR, using 2-methyl-2H-pyrazole-3-carboxylic acid (2-methyl-4-o-tolylazo-phenyl)-amide (CH-223191), which is an AhR antagonist.

RESULTS

The treatment of HPDLCs with BaP reduced mRNA expression of osteogenic genes, alkaline phosphatase activity, mineralization and collagen synthesis. The treatment with CH-223191 subsequently restored the observed suppressive effects of BaP on HPDLCs.

CONCLUSIONS

The present results suggest that BaP exerts inhibitory effects on the maintenance of homeostasis in HPDL tissue, such as osteoblastic differentiation and collagen synthesis of HPDLCs, and that this signaling pathway could be suppressed by preventing the transactivity of AhR. Future studies may unveil a role for the inhibition of AhR as a promising therapeutic agent for periodontal disease caused by cigarette smoking.

Acceptance of surrogate end points in clinical trials supporting approval of drugs for cancer treatment by the Japanese regulatory agency

BACKGROUND

This study investigated the historic use of different end points to support approval of drugs for cancer treatment in Japan.

PATIENTS AND METHODS

Anticancer drugs approved between April 2001 and April 2014 were comprehensively investigated using publicly available information.

RESULTS

Before the revision of the guideline for oncology drugs in April 2006 in Japan, >80% of end points supporting approval were response rate and overall survival (OS) was not frequent. After the revision of the guideline in Japan, using OS in pivotal clinical trials applied for approval increased to more than approximately one-third of oncology drugs, although trials with an end point of response rate decreased. Regarding drugs for major cancers including non-small-cell lung cancer, gastric cancer, colorectal cancer, and breast cancer, survival was used as an end point in 44.0%, whereas surrogate end points were used in 56.0%. Exploration of potential factors for using surrogate end points other than survival carried out through determinations of odds ratios and 95% confidence intervals identified 'orphan drug designation in Japan' and 'accelerated approval by the U.S. Food and Drug Administration' as significant factors.

CONCLUSIONS

The revised guideline for oncology drugs in Japan requires the results of phase 3 studies with survival as an end point at the time of new drug application at least for major cancers. The regulatory agency in Japan also accepts surrogate end points as end points supporting approval besides survival; however, the number of surrogate end points has decreased after the revision of the guideline. We consider that accepting surrogate end points in the Japanese regulatory systems is important to approve oncology drugs quickly in Japan.

Correction: Highly selective aluminium-catalysed intramolecular Prins reaction for l-menthol synthesis

Correction for ‘Highly selective aluminium-catalysed intramolecular Prins reaction for l-menthol synthesis’ by H. Itoh et al., RSC Adv., 2014, 4, 61619–61623.

Operation of a 400MHz NMR magnet using a (RE:Rare Earth)Ba2Cu3O7-x high-temperature superconducting coil: Towards an ultra-compact super-high field NMR spectrometer operated beyond 1GHz

High-temperature superconductors (HTS) are the key technology to achieve super-high magnetic field nuclear magnetic resonance (NMR) spectrometers with an operating frequency far beyond 1GHz (23.5T). (RE)Ba₂Cu₃O_7-x (REBCO, RE: rare earth) conductors have an advantage over Bi₂Sr₂Ca₂Cu₃O_10-x (Bi-2223) and Bi₂Sr₂CaCu₂O_8-x (Bi-2212) conductors in that they have very high tensile strengths and tolerate strong electromagnetic hoop stress, thereby having the potential to act as an ultra-compact super-high field NMR magnet. As a first step, we developed the world's first NMR magnet comprising an inner REBCO coil and outer low-temperature superconducting (LTS) coils. The magnet was successfully charged without degradation and mainly operated at 400MHz (9.39T). Technical problems for the NMR magnet due to screening current in the REBCO coil were clarified and solved as follows: (i) A remarkable temporal drift of the central magnetic field was suppressed by a current sweep reversal method utilizing ∼10% of the peak current. (ii) A Z2 field error harmonic of the main coil cannot be compensated by an outer correction coil and therefore an additional ferromagnetic shim was used. (iii) Large tesseral harmonics emerged that could not be corrected by cryoshim coils. Due to those harmonics, the resolution and sensitivity of NMR spectra are ten-fold lower than those for a conventional LTS NMR magnet. As a result, a HSQC spectrum could be achieved for a protein sample, while a NOESY spectrum could not be obtained. An ultra-compact 1.2GHz NMR magnet could be realized if we effectively take advantage of REBCO conductors, although this will require further research to suppress the effect of the screening current.

Successful transplantation of kidney allografts in sensitized rats after syngeneic hematopoietic stem cell transplantation and fludarabine

Current methods to remove donor-specific HLA antibody (DSA) from sensitized patients remain imperfect. We tested novel approaches to desensitization using an animal model of allogeneic sensitization with skin grafts from dark agouti (DA) to Lewis rats. At the peak IgG alloantibody response we transplanted DA kidneys into nephrectomized Lewis recipients (n = 6) and all died within 10 days from antibody-mediated rejection (AMR). Allogeneic hematopoietic stem cell transplants (HSCT) from DA donors failed to engraft after lethal or sub-lethal irradiation. Sensitized rats given lethal irradiation plus syngeneic green fluorescent protein (GFP) + HSCT had repopulation of blood, spleen, thymus and lymph nodes by GFP+ cells. At 2 months after HSCT, serum DSA levels were reduced 60-70% and DSA (IgG) production in cultured splenocytes was also significantly decreased. However, there was only a modest improvement in graft survival from an average of 6.5 to 13.9 (n = 9) days. Adding seven daily doses of fludarabine to the preconditioning regimen resulted in long-term survival (>90 days) in 7 out of 10 rat kidney allografts. We conclude that syngeneic HSCT performed after preconditioning with irradiation and fludarabine can reduce DSA, prevent DSA rebound and AMR, enabling successful transplantation in animals with strong antibody reactivity to the donor MHC.

Microbial community in persistent apical periodontitis: a 16S rRNA gene clone library analysis

AIM

To characterize the microbial composition of persistent periapical lesions of root filled teeth using a molecular genetics approach.

METHODOLOGY

Apical lesion samples were collected from 12 patients (23-80 years old) who visited the Kyushu University Hospital for apicectomy with persistent periapical lesions associated with root filled teeth. DNA was directly extracted from each sample and the microbial composition was comprehensively analysed using clone library analysis of the 16S rRNA gene. Enterococcus faecalis, Candida albicans and specific fimA genotypes of Porphyromonas gingivalis were confirmed using polymerase chain reaction (PCR) analysis with specific primers.

RESULTS

Bacteria were detected in all samples, and the dominant findings were P. gingivalis (19.9%), Fusobacterium nucleatum (11.2%) and Propionibacterium acnes (9%). Bacterial diversity was greater in symptomatic lesions than in asymptomatic ones. In addition, the following bacteria or bacterial combinations were characteristic to symptomatic lesions: Prevotella spp., Treponema spp., Peptostreptococcaceae sp. HOT-113, Olsenella uli, Slackia exigua, Selemonas infelix, P. gingivalis with type IV fimA, and a combination of P. gingivalis, F. nucleatum, and Peptostreptococcaceae sp. HOT-113 and predominance of Streptococcus spp. On the other hand, neither Enterococcus faecalis nor C. albicans were detected in any of the samples.

CONCLUSION

Whilst a diverse bacterial species were observed in the persistent apical lesions, some characteristic patterns of bacterial community were found in the symptomatic lesions. The diverse variation of community indicates that bacterial combinations as a community may cause persistent inflammation in periapical tissues rather than specific bacterial species.

Identification of transactivation-responsive DNA-binding protein 43 (TARDBP43; TDP-43) as a novel factor for TNF-α expression upon lipopolysaccharide stimulation in human monocytes

BACKGROUND AND OBJECTIVE

Tumor necrosis factor alpha (TNF-α) is a major cytokine implicated in various inflammatory diseases. The nature of the nuclear factors associated with human TNF-α gene regulation is not well elucidated. We previously identified a novel region located from -550 to -487 in human TNF-α promoter that did not contain the reported binding sites for nuclear factor kappa B (NF-κB) but showed lipopolysaccharide (LPS)-induced transcriptional activity. The purpose of this study is to identify novel factors that bind to the promoter region and regulate TNF-α expression.

MATERIAL AND METHODS

To identify DNA-binding proteins that bound to the target region of TNF-α promoter, a cDNA library from LPS-stimulated human monocytic cell line THP-1 was screened using a yeast one-hybrid system. Cellular localizations of the DNA-binding protein in the cells were examined by subcellular immunocytochemistry. Nuclear amounts of the protein in LPS-stimulated THP-1 cells were identified by western blot analysis. Expression of mRNA of the protein in the cells was quantified by real-time polymerase chain reaction. Electrophoretic mobility shift assays were performed to confirm the DNA-binding profile. Overexpression of the protein and knockdown of the gene were also performed to investigate the role for TNF-α expression.

RESULTS

Several candidates were identified from the cDNA library and transactivation-responsive DNA-binding protein 43 (TARDBP43; TDP-43) was focused on. Western blot analysis revealed that nuclear TDP-43 protein was increased in the LPS-stimulated THP-1 cells. Expression of TDP-43 mRNA was already enhanced before TNF-α induction by LPS. Electrophoretic mobility shift assay analysis showed that nuclear extracts obtained by overexpressing FLAG-tagged TDP-43 bound to the -550 to -487 TNF-α promoter fragments. Overexpression of TDP-43 in THP-1 cells resulted in an increase of TNF-α expression. Knockdown of TDP-43 in THP-1 cells downregulated TNF-α expression.

CONCLUSION

We identified TDP-43 as one of the novel TNF-α factors and found that it bound to the LPS-responsive element in the TNF-α promoter to increase TNF-α expression.

Effects of Activin A on the phenotypic properties of human periodontal ligament cells

Periodontal ligament (PDL) tissue plays an important role in tooth preservation by structurally maintaining the connection between the tooth root and the bone. The mechanisms involved in the healing and regeneration of damaged PDL tissue, caused by bacterial infection, caries and trauma, have been explored. Accumulating evidence suggests that Activin A, a member of the transforming growth factor-β (TGF-β) superfamily and a dimer of inhibinβa, contributes to tissue healing through cell proliferation, migration, and differentiation of various target cells. In bone, Activin A has been shown to exert an inhibitory effect on osteoblast maturation and mineralization. However, there have been no reports examining the expression and function of Activin A in human PDL cells (HPDLCs). Thus, we aimed to investigate the biological effects of Activin A on HPDLCs. Activin A was observed to be localized in HPDLCs and rat PDL tissue. When PDL tissue was surgically damaged, Activin A and IL-1β expression increased and the two proteins were shown to be co-localized around the lesion. HPDLCs treated with IL-1β or TNF-α also up-regulated the expression of the gene encoding inhibinβa. Activin A promoted chemotaxis, migration and proliferation of HPDLCs, and caused an increase in fibroblastic differentiation of these cells while down-regulating their osteoblastic differentiation. These osteoblastic inhibitory effects of Activin A, however, were only noted during the early phase of HPDLC osteoblastic differentiation, with later exposures having no effect on differentiation. Collectively, our results suggest that Activin A could be used as a therapeutic agent for healing and regenerating PDL tissue in response to disease, trauma or surgical reconstruction.

Expression and effects of epidermal growth factor on human periodontal ligament cells

Repair of damaged periodontal ligament (PDL) tissue is an essential challenge in tooth preservation. Various researchers have attempted to develop efficient therapies for healing and regenerating PDL tissue based on tissue engineering methods focused on targeting signaling molecules in PDL stem cells and other mesenchymal stem cells. In this context, we investigated the expression of epidermal growth factor (EGF) in normal and surgically wounded PDL tissues and its effect on chemotaxis and expression of osteoinductive and angiogenic factors in human PDL cells (HPDLCs). EGF as well as EGF receptor (EGFR) expression was observed in HPDLCs and entire PDL tissue. In a PDL tissue-injured model of rat, EGF and IL-1β were found to be upregulated in a perilesional pattern. Interleukin-1β induced EGF expression in HPDLCs but not EGFR. It also increased transforming growth factor-α (TGF-α) and heparin-binding EGF-like growth factor (HB-EGF) expression. Transwell assays demonstrated the chemotactic activity of EGF on HPDLCs. In addition, EGF treatment significantly induced secretion of bone morphogenetic protein 2 and vascular endothelial growth factor, and gene expression of interleukin-8 (IL-8), and early growth response-1 and -2 (EGR-1/2). Human umbilical vein endothelial cells developed well-formed tube networks when cultured with the supernatant of EGF-treated HPDLCs. These results indicated that EGF upregulated under inflammatory conditions plays roles in the repair of wounded PDL tissue, suggesting its function as a prospective agent to allow the healing and regeneration of this tissue.

Regeneration of the periodontium for preservation of the damaged tooth

The population of the world grows every year, and life expectancy tends to increase. Thus, long-term preservation of teeth in aged individuals is an urgent issue. The main causes of tooth loss are well known to be periodontitis, caries, fractures, and orthodontic conditions. Although implant placement is a widely accepted treatment for tooth loss, most patients desire to preserve their own teeth. Many clinicians and researchers are therefore challenged to treat and preserve teeth that are irreversibly affected by deep caries, periodontitis, fractures, and trauma. Tissue engineering techniques are beneficial in addressing this issue; stem cells, signal molecules, and scaffolds are the main elements of such techniques. In this review, we describe these three elements with respect to their validation for regeneration of the periodontium and focus particularly on the potency of diverse scaffolds. In addition, we provide a short overview of the ongoing studies of 4-methacryloxyethyl trimellitate anhydride/methyl methacrylate-tri-n-butyl-borane resin including calcium chloride or hydroxyapatite for periodontium regeneration.

Semaphorin 3A induces mesenchymal-stem-like properties in human periodontal ligament cells

Periodontal ligament stem cells (PDLSCs) have recently been proposed as a novel option in periodontal regenerative therapy. However, one of the issues is the difficulty of stably generating PDLSCs because of the variation of stem cell potential between donors. Here, we show that Semaphorin 3A (Sema3A) can induce mesenchymal-stem-like properties in human periodontal ligament (PDL) cells. Sema3A expression was specifically observed in the dental follicle during tooth development and in parts of mature PDL tissue in rodent tooth and periodontal tissue. Sema3A expression levels were found to be higher in multipotential human PDL cell clones compared with low-differentiation potential clones. Sema3A-overexpressing PDL cells exhibited an enhanced capacity to differentiate into both functional osteoblasts and adipocytes. Moreover, PDL cells treated with Sema3A only at the initiation of culture stimulated osteogenesis, while Sema3A treatment throughout the culture had no effect on osteogenic differentiation. Finally, Sema3A-overexpressing PDL cells upregulated the expression of embryonic stem cell markers (NANOG, OCT4, and E-cadherin) and mesenchymal stem cell markers (CD73, CD90, CD105, CD146, and CD166), and Sema3A promoted cell division activity of PDL cells. These results suggest that Sema3A may possess the function to convert PDL cells into mesenchymal-stem-like cells.

Highly selective aluminium-catalysed intramolecular Prins reaction for l-menthol synthesis

The perfect production of l-menthol.

Long-term efficacy and safety of sitagliptin in the treatment of Japanese Type 2 diabetes (ASSET-K1) to a target of HbA1c <7%

BACKGROUND

Few studies have investigated the factors related to improvement and maintenance of glycemic control with sitagliptin in Type 2 diabetes (T2D) patients.

AIM

To identify factors contributing to reaching and maintaining glycated hemoglobin (HbA1c) <7% with sitagliptin in Japanese T2D patients.

SUBJECTS AND METHODS

This study included 1327 patients who were: taking sitagliptin as monotherapy; switched to sitagliptin; or taking sitagliptin in combination therapy. At baseline and 1, 3, 6, and 12 months after starting sitagliptin, weight, body mass index (BMI), HbA1c, fasting plasma glucose (FPG), and post-prandial plasma glucose (PPG) were measured. The subjects were divided into a group that achieved HbA1c<7% at 12 months, a poor control group (HbA1c≥8% at 12 months), and a discontinued group. Multiple regression analysis was performed to identify factors contributing to long-term control and maintenance with sitagliptin treatment.

RESULTS

HbA1c decreased significantly from 8.0% at baseline to 7.3%, but weight was unchanged. FPG and PPG improved significantly. The HbA1c<7% group had a significantly higher age and a signifi cant ly lower BMI at baseline than the HbA1c≥8% group and the discontinued group. On multivariate regression analysis, baseline HbA1c, baseline BMI, and Δbody weight after 12 months were significantly related to HbA1c reduction. The most common adverse event was hypoglycemia, and the most common adverse event responsible for discontinuation was constipation.

CONCLUSIONS

HbA1c<7.0% was achieved in 31% of T2D patients who had poor control with conventional treatment. Weight management is important for maintaining good long-term control with sitagliptin.

Follicular dendritic cell-secreted protein is decreased in experimental periodontitis concurrently with the increase of interleukin-17 expression and the Rankl/Opg mRNA ratio

BACKGROUND AND OBJECTIVE

T-helper type 17 (Th17) cells produce interleukin-17 (IL-17) and help to protect against inflammation and infection in periodontal disease. Furthermore, while follicular dendritic cell-secreted protein (FDC-SP) may be involved in the inflammation of periodontal tissue, the biological role of FDP-SP in periodontal disease is still unknown. The purpose of the present study was to clarify the expression of IL-17 and FDC-SP in experimental periodontitis in rats.

MATERIAL AND METHODS

Seven-week-old male Wistar rats were divided into baseline control, sham and test groups. Experimental periodontitis was induced by placing a ligature in the mesiopalatal area, and untreated rats served as a baseline control group. Morphological changes in alveolar bone were investigated 7, 14 and 28 d after treatment. Expression of the Rankl, osteoprotegerin (Opg) and Il17 genes was analyzed 5 and 7 d after the induction of experimental periodontitis.

RESULTS

Alveolar bone resorption progressed in the test group for 7 d, but not thereafter. At 5 d after the induction of periodontitis, the Rankl/Opg mRNA ratio and the expression of IL-17 in the test group were significantly increased compared with the respective values in the baseline control group; however, there were no significant differences between the test and control groups at 7 d. The expression of FDC-SP was significantly decreased in the test group compared with the baseline control group at 5 and 7 d after the induction of periodontitis, and this value had returned to normal levels at 14 and 28 d.

CONCLUSION

These results suggest that both IL-17 and FDC-SP could be involved in the inflammatory response, and FDC-SP in the junctional epithelium might play an important role in the Th17 cell-related immune response.

Early and late outcomes of inflammatory abdominal aortic aneurysms: comparison with the outcomes after open surgical and endovascular aneurysm repair in literature reviews

AIM

The aim of this study was to analyze the clinical characteristics, operative management and early and late outcomes of Inflammatory abdominal aortic aneurysms (IAAAs) in our vascular service, retrospectively and to compare with the outcomes of open and endovascular aneurysm repair (EVAR) in the patients with IAAAs in literature reviews.

METHODS

Between January 1990 and December 2011, this series included twenty-four patients with IAAAs who underwent surgical treatment. The mean length of follow-up was 37.6 months (range 3-108). Kaplan-Meier life tables were used to calculate survival rate.

RESULTS

Fifteen patients (60%) were symptomatic including 3 patients with hydronephrosis. Seven patients with severe symptoms underwent emergency operations. Twenty four patients underwent open surgical AAA repair. The 30 - day mortality rates were 0%. All patients had successful post operative courses and followed as outpatients in an elective situation. The ten year cumulative survival rate was 70%. The early and late mortality was the same for open repair compared to non-inflammatory AAA.

CONCLUSIONS

IAAA compared with non-IAAA is associated with a higher incidence of preoperative morbidity, however operative mortality rates are lower. EVAR has lower early operative mortality rates, however, there are some problems such as remaining periaortic fibrosis and hydronephrosis in approximately half of IAAA patients after EVAR.

Prospective potency of TGF-β1 on maintenance and regeneration of periodontal tissue

Periodontal ligament (PDL) tissue, central in the periodontium, plays crucial roles in sustaining tooth in the bone socket. Irreparable damages of this tissue provoke tooth loss, causing a decreased quality of life. The question arises as to how PDL tissue is maintained or how the lost PDL tissue can be regenerated. Stem cells included in PDL tissue (PDLSCs) are widely accepted to have the potential to maintain or regenerate the periodontium, but PDLSCs are very few in number. In recent studies, undifferentiated clonal human PDL cell lines were developed to elucidate the applicable potentials of PDLSCs for the periodontal regenerative medicine based on cell-based tissue engineering. In addition, it has been suggested that transforming growth factor-beta 1 is an eligible factor for the maintenance and regeneration of PDL tissue.

Assessment of the Plasma/Serum IgG Test to Screen for Periodontitis

Chronic periodontitis is a silent infectious disease prevalent worldwide and affects lifestyle-related diseases. Therefore, efficient screening of patients is essential for general health. This study was performed to evaluate prospectively the diagnostic utility of a blood IgG antibody titer test against periodontal pathogens. Oral examination was performed, and IgG titers against periodontal pathogens were measured by ELISA in 1,387 individuals. The cut-off value of the IgG titer was determined in receiver operating characteristic curve analysis, and changes in periodontal clinical parameters and IgG titers by periodontal treatment were evaluated. The relationships between IgG titers and severity of periodontitis were analyzed. The best cut-off value of IgG titer against Porphyromonas gingivalis for screening periodontitis was 1.682. Both clinical parameters and IgG titers decreased significantly under periodontal treatment. IgG titers of periodontitis patients were significantly higher than those of healthy controls, especially in those with sites of probing pocket depth over 4 mm. Multiplied cut-off values were useful to select patients with severe periodontitis. A blood IgG antibody titer test for Porphyromonas gingivalis is useful to screen hitherto chronic periodontitis patients (ClinicalTrials.gov number NCT01658475).