Efficacy of Mitiglinide Combined with Dapagliflozin in Streptozotocin-nicotinamide-induced Type 2 Diabetic Rats and in Zucker Fatty Rats

The efficacy of the combination of the rapid-acting insulin secretagogue mitiglinide and the sodium-glucose cotransporter 2 (SGLT2) inhibitor dapagliflozin was explored in streptozotocin-nicotinamide-induced type 2 diabetic (STZ-NA) rats and in Zucker fatty (ZF) rats. The STZ-NA rats were prepared at 8 weeks of age. At 9 weeks of age, the combination study was conducted by oral glucose tolerance test (OGTT). At 13 weeks of age, ZF rats were dosed orally with dapagliflozin once daily up to the 22(nd) day. At days 15 and 22, the combination study was conducted by OGTT. In 2 different animal models, plasma glucose levels were strongly suppressed by the combination of mitiglinide and dapagliflozin as compared with either drug alone. The urinary glucose excretion was drastically elevated in the dapagliflozin group, but the combination with mitiglinide suppressed it about 50%. In STZ-NA rats, the plasma insulin secretion by the combination of both drugs was about at the same level as in the mitiglinide group. In ZF rats, the plasma insulin secretion by the combination of both drugs was less than mitiglinide group. Thus, in 2 different animal models, the combination of mitiglinide and dapagliflozin showed stronger antihyperglycemic action accompanied by less insulin secretion than mitiglinide alone, and reduced the urinary glucose excretion as compared with dapagliflozin used alone. These results indicate that the combination of mitiglinide and dapagliflozin can be a promising combination for the treatment of diabetic patients.

GLCCI1 variant accelerates pulmonary function decline in patients with asthma receiving inhaled corticosteroids

BACKGROUND

In steroid-naive patients with asthma, several gene variants are associated with a short-term response to inhaled corticosteroid (ICS) treatment; this has mostly been observed in Caucasians. However, not many studies have been conducted for other ethnicities. Here, we aimed to determine the relationship between the annual decline in forced expiratory flow volume in one second (FEV1 ) and the variant of the glucocorticoid-induced transcript 1 gene (GLCCI1) in Japanese patients with asthma receiving long-term ICS treatment, taking into account the effect of high serum periostin levels, a known association factor of pulmonary function decline and a marker of refractory eosinophilic/Th2 inflammation.

METHODS

In this study, 224 patients with asthma receiving ICS treatment for at least 4 years were enrolled. The effects of single-nucleotide polymorphisms (SNPs) in GLCCI1, stress-induced phosphoprotein 1 (STIP1), and T gene on the decline in FEV1 of 30 ml/year or greater were determined.

RESULTS

Besides the known contributing factors, that is, the most intensive treatment step, ex-smoking, and high serum periostin levels (≥95 ng/ml), the GG genotype of GLCCI1 rs37973, and not other SNPs, was independently associated with a decline in FEV1 of 30 ml/year or greater. When patients were stratified according to their serum periostin levels, the GG genotype of rs37973 was significantly associated with blood eosinophilia (≥250/μl) in the high serum periostin group.

CONCLUSIONS

A GLCCI1 variant is a risk factor of pulmonary function decline in Japanese patients with asthma receiving long-term ICS treatment. Thus, GLCCI1 may be associated with response to ICS across ethnicities.

Spontaneous exciton dissociation in carbon nanotubes

Simultaneous photoluminescence and photocurrent measurements on individual single-walled carbon nanotubes reveal spontaneous dissociation of excitons into free electron-hole pairs. The correlation of luminescence intensity and photocurrent shows that a significant fraction of excitons are dissociating before recombination. Furthermore, the combination of optical and electrical signals also allows for extraction of the absorption cross section and the oscillator strength. Our observations explain the reasons why photoconductivity measurements in single-walled carbon nanotubes are straightforward despite the large exciton binding energies.

Toll-like receptor 2-mediated modulation of growth and functions of regulatory T cells by oral streptococci

This study was designed to determine whether oral streptococci modulate the growth and functions of regulatory T cells. Heat-killed cells of wild-type strains of Streptococcus gordonii and Streptococcus mutans induced the Toll-like receptor 2 (TLR2) -mediated nuclear factor-κB (NF-κB) activation, but their lipoprotein-deficient strains did not. Stimulation with these streptococci resulted in a significant increase in the frequency of CD4(+) CD25(+) Foxp3(+) regulatory T cells in splenocytes derived from both TLR2(+/+) and TLR2(-/-) mice, but the level of increase in TLR2(+/+) splenocytes was stronger than that in TLR2(-/-) splenocytes. Both strains of S. gordonii enhanced the proliferation of CD4(+) CD25(+) Foxp3(+) regulatory T cells isolated from TLR2(+/+) mice at the same level as those from TLR2(-/-) mice in an interleukin-2-independent manner. However, wild-type and lipoprotein-deficient strains of both streptococci did not enhance the suppressive activity of the isolated regulatory T cells in vitro, but rather inhibited it. TLR ligands also inhibited the suppressive activity of the regulatory T cells. Inhibition of the suppressive activity was recovered by the addition of anti-IL-6 antibody. Pretreatment of antigen-presenting cells with the NF-κB inhibitor BAY11-7082 enhanced the suppressive activity of the regulatory T cells. These results suggested that interleukin-6 produced by antigen-presenting cells inhibits the suppressive activity of the regulatory T cells. Wild-type strain, but not lipoprotein-deficient strain, of S. gordonii reduced the frequency of CD4(+)  CD25(+)  Foxp3(+) regulatory T cells in the acute infection model, whereas both strains of S. gordonii increased it in the chronic infection model mice. Hence, this study suggests that oral streptococci are capable of modulating the growth and functions of regulatory T cells in vitro and in vivo.

A circulating heat-resistant mucin-like antigen in patients with lung-cancer detected by a new murine monoclonal-antibody

We discovered a circulating mucin-like antigen designated as CAM-14 detected by a new murine monoclonal antibody KL-14 (IgM). We found different heat resistant properties between serum CAM- 14 from normal individuals and from lung cancer patients. Heat treatment had less effect on the levels of CAM-14 in sera from lung cancer patients, whereas CAM-14 levels in sera from normal individuals were markedly decreased after heat treatment at tempratures > 65-degrees-C. As a serum tumor marker, CAM- 14 had only very low levels of false-positive values with a high specificity and effectively increased the positive rate for lung cancer patients when used together with carcinoembryonic antigen.

Origin of heterogeneity of interleukin-6 (IL-6) levels in malignant pleural effusions

We measured interleukin-6 (IL-6) concentrations from 48 malignant pleural effusions by an enzyme immunoassay and found a marked heterogeneity of the concentrations. The histological type of the malignant cells and total counts or differentials of the cells in effusions could not account for the heterogeneity. We newly established five malignant cell lines and found that the amounts of IL-6 produced by them were well correlated with IL-6 concentrations of the effusions from which these lines were derived (r=0.96; p<0.01). These results suggest that a marked heterogeneity of IL-6 concentrations in malignant effusions reflects the differential production of IL-6 by malignant cells in pleural space.

Induction chemotherapy followed by gefitinib and concurrent thoracic radiotherapy for unresectable locally advanced adenocarcinoma of the lung: a multicenter feasibility study (JCOG 0402)

BACKGROUND

We conducted a feasibility study of induction chemotherapy followed by gefitinib and thoracic radiotherapy (TRT) for unresectable locally advanced adenocarcinoma of the lung.

PATIENTS AND METHODS

Patients received induction chemotherapy with cisplatin (80 mg/m(2), days 1 and 22) and vinorelbine (25 mg/m(2), days 1, 8, 22, and 29) followed by gefitinib (250 mg daily, beginning on day 43, for 1 year) and TRT (60 Gy/30 fractions, days 57-98). The primary end point was feasibility, which was defined as the proportion of patients who completed 60 Gy of TRT and received >75% of the planned dose of gefitinib without developing grade 2 or worse pneumonitis.

RESULTS

Of the 38 enrolled patients, 23 patients [60.5% ; 80% confidence interval (CI) 48.8-71.3] completed treatment without experiencing grade 2 or worse pneumonitis. During the chemoradiation phase, grade 3-4 alanine aminotransferase elevations were observed in 37.1% of the patients. The overall response rate was 73.0% . The median survival time was 28.5 months (95% CI 22.5-38.2), and the 2-year survival rate was 65.4% .

CONCLUSIONS

Although the results did not meet our criterion for feasibility, the toxicity was acceptable. This treatment warrants further evaluation among patients with locally advanced non-small-cell lung cancer harboring epidermal growth factor receptor mutations.

Recent advancement of observing living cells in the esophagus using CM double staining: endocytoscopic atypia classification

Magnification endoscopy enables in vivo evaluation of gastrointestinal mucosa. Furthermore, endocytoscopy (ECS) with ultra-high magnification enables in vivo observation of cellular atypia during routine endoscopic examination. The purpose of this study is to clarify the efficacy of ECS and endocytoscopic atypia (ECA) classification in various types of benign and malignant pathology in the esophagus. Consecutive 110 patients, who underwent ECS in our institution from March 2003 to December 2009, were included in this study. One hundred and forty-six esophageal lesions were classified according to ECA classification, and these endocytoscopic images were compared with histological images. We categorized endocytoscopic images into five categories according to size and uniformity of nuclei, number of cells and regularity of cellular arrangement. Eighty-one out of 89 ECA-1 to ECA-3 lesions (91.0%) corresponded to Vienna categories 1 to 3. Seventy-one out of 84 ECA-4 or ECA-5 lesions (91.2%) corresponded to Vienna category 4 or 5. Overall accuracy of ECS was 91.3%, providing images similar to conventional hematoxylin and eosin staining. In addition, with ECS, we can take an 'optical biopsy' even in patients with cardiovascular disease without interrupting anticoagulant therapy. A newly designed single charge-coupled device endocytoscope allows observation of target tissue noninvasibly from regular magnification to ultra-high magnification. The development of ECS has opened the door to in vivo cellular imaging, enabling endoscopic diagnosis of tissue cytological atypia during routine endoscopic examination.

A Shorter 146 Sm Half-Life Measured and Implications for 146 Sm- 142 Nd Chronology in the Solar System

The extinct p-process nuclide (146)Sm serves as an astrophysical and geochemical chronometer through measurements of isotopic anomalies of its α-decay daughter (142)Nd. Based on analyses of (146)Sm/(147)Sm α-activity and atom ratios, we determined the half-life of (146)Sm to be 68 ± 7 (1σ) million years, which is shorter than the currently used value of 103 ± 5 million years. This half-life value implies a higher initial (146)Sm abundance in the early solar system, ((146)Sm/(144)Sm)(0) = 0.0094 ± 0.0005 (2σ), than previously estimated. Terrestrial, lunar, and martian planetary silicate mantle differentiation events dated with (146)Sm-(142)Nd converge to a shorter time span and in general to earlier times, due to the combined effect of the new (146)Sm half-life and ((146)Sm/(144)Sm)(0) values.

A health-risk appraisal model and endoscopic mass screening for esophageal cancer in Japanese men

A strong association between inactive aldehyde dehydrogenase-2 (ALDH2) and risk of esophageal cancer has been demonstrated in East Asian drinkers. An alcohol flushing questionnaire asking about past and current tendency for facial flushing to occur after drinking a glass (≈180 mL) of beer predicts the presence of inactive ALDH2 among Japanese aged 40 years or older with a sensitivity and specificity of approximately 90%. We invented a health-risk appraisal (HRA) model that makes it possible to identify Japanese men who are at high risk for esophageal cancer based on their past and current alcohol flushing tendency, drinking, smoking, and intake of vegetables and fruits. Between 2008 and 2009, 2221 Japanese men aged 50 years or older filled out the HRA questionnaire before undergoing a screening examination by upper gastrointestinal endoscopy at five medical facilities. The endoscopic examination resulted in a diagnosis of esophageal cancer in 19 subjects, and 117 (5.27%) subjects had an HRA score ≥ 11. The proportion of subjects with an HRA score ≥ 11 was higher in the 50-69 age group (6.11-6.88%) than in 70-89 age group (2.84-2.86%). The esophageal cancer detection rate was 4.27% among the subjects with an HRA score ≥ 11 and only 0.67% among the other subjects. Based on a receiver operating characteristic curve analysis, when an HRA score of ≥ 9 was used for subjects aged 50-69 years and of ≥ 8 for those aged 70-89 years as the cutoff value to select individuals with a high risk for esophageal cancer, its sensitivity and false-positive rate was 52.6% and 15.2%, respectively, and the cancer detection rate was 2.91% in the high-risk group, as opposed to 0.48% in the other group. In conclusion, the high detection rates for esophageal cancer in the high-risk groups encouraged screening based on our HRA model in larger Japanese populations.

Imatinib causes epigenetic alterations of PTEN gene via upregulation of DNA methyltransferases and polycomb group proteins

We have recently reported the possible imatinib-resistant mechanism; long-term exposure of leukemia cells to imatinib downregulated levels of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) via hypermethylation of its promoter region (Leukemia 2010; 24: 1631). The present study explored the molecular mechanisms by which imatinib caused methylation on the promoter region of this tumor suppressor gene in leukemia cells. Real-time reverse transcription PCR found that long-term exposure of chronic eosinophilic leukemia EOL-1 cells expressing FIP1L1/platelet-derived growth factor receptor-α to imatinib induced expression of DNA methyltransferase 3A (DNMT3A) and histone-methyltransferase enhancer of zeste homolog 2 (EZH2), a family of polycomb group, thereby increasing methylation of the gene. Immunoprecipitation assay found the increased complex formation of DNMT3A and EZH2 proteins in these cells. Moreover, chromatin immunoprecipitation assay showed that amounts of both DNMT3A and EZH2 proteins bound around the promoter region of PTEN gene were increased in EOL-1 cells after exposure to imatinib. Furthermore, we found that levels of DNMT3A and EZH2 were strikingly increased in leukemia cells isolated from individuals with chronic myelogenous leukemia (n=1) and Philadelphia chromosome-positive acute lymphoblastic leukemia (n=2), who relapsed after treatment with imatinib compared with those isolated at their initial presentation. Taken together, imatinib could cause drug-resistance via recruitment of polycomb gene complex to the promoter region of the PTEN and downregulation of this gene's transcripts in leukemia patients.

Regulated histone methyltransferase and demethylase complexes in the control of genes by nuclear receptors

Liganded nuclear receptors (NRs) are DNA-binding transcription factors that control the transcription of target genes. Such NRs exert their transcriptional functions via ligand binding-induced interactions with a number of coregulator complexes to reorganize chromatin state. Intensive investigation of NR coregulator complexes has revealed that, besides histone acetylation, histone methylation is critical for ligand-dependent transcriptional controls by NRs. Our recent biochemical screening for NR coregulator complexes showed that the enzymatic activities of these histone methylation/demethylation complexes are under the control of posttranslational modifications (PTMs) of their catalytic subunit. Characterization of such regulated complexes has established the concept that transcriptional coregulator complexes sense and decode cellular signals at the molecular level. In this symposium review, we will illustrate our recent findings regarding PTM-based regulation of NR transcriptional control and discuss how these findings are applicable to the diverse roles of NR coregulators in interpreting regulatory signals into proper gene regulation.

Impaired fracture healing in macrophage migration inhibitory factor-deficient mice

This study investigated the role of macrophage migration inhibitory factor (MIF) in fracture repair using MIF gene-deficient mice (MIF KO). Fracture healing was delayed in MIF KO, and this was mainly due to the delay in the mineralization of osteoid within the fracture callus.

INTRODUCTION

We previously reported that the expression of macrophage migration inhibitory factor (MIF) was up-regulated during the fracture healing process in rats. However, its role in the pathophysiology of this process remained unclear. The aim of the present study was to clarify the role of MIF in the fracture healing process using MIF gene-deficient mice (MIF KO).

METHODS

Bone repair in wild-type mice (WT) and MIF KO (n = 70, respectively) was investigated using a tibia fracture model. Radiographic, biomechanical, histological, bone histomorphometric, and molecular analyses were performed.

RESULTS

Post-fracture biomechanical testing showed that maximum load and stiffness were significantly lower in MIF KO than in WT on day 42. However, similar levels were observed between the two groups on day 84. Bone histomorphometric analysis revealed significantly higher osteoid volume, a lower mineral apposition rate, and smaller numbers of osteoclasts in the MIF KO callus compared to the WT callus. The messenger ribonucleic acid expressions of matrix metalloproteinase (MMP)-2, membranous type 1-MMP, cathepsin K, and tissue nonspecific alkaline phosphatase were found to be significantly suppressed in the MIF KO callus.

CONCLUSION

The results of the present study suggest that delayed fracture healing in MIF KO was mainly attributable to a delay in osteoid mineralization.