Gene suppressing therapy for Pelizaeus-Merzbacher disease using artificial microRNA.

Copy number increase or decrease of certain dosage-sensitive genes may cause genetic diseases with distinct phenotypes, conceptually termed genomic disorders. The most common cause of Pelizaeus-Merzbacher disease (PMD), an X-linked hypomyelinating leukodystrophy, is genomic duplication encompassing the entire proteolipid protein 1 (PLP1) gene. Although the exact molecular and cellular mechanisms underlying PLP1 duplication, which causes severe hypomyelination in the central nervous system, remain largely elusive, PLP1 overexpression is likely the fundamental cause of this devastating disease. Here, we investigated if adeno-associated virus-mediated (AAV-mediated) gene-specific suppression may serve as a potential cure for PMD by correcting quantitative aberrations in gene products. We developed an oligodendrocyte-specific Plp1 gene suppression therapy using artificial microRNA under the control of human CNP promoter in a self-complementary AAV (scAAV) platform. A single direct brain injection achieved widespread oligodendrocyte-specific Plp1 suppression in the white matter of WT mice. AAV treatment in Plp1-transgenic mice, a PLP1 duplication model, ameliorated cytoplasmic accumulation of Plp1, preserved mature oligodendrocytes from degradation, restored myelin structure and gene expression, and improved survival and neurological phenotypes. Together, our results provide evidence that AAV-mediated gene suppression therapy can serve as a potential cure for PMD resulting from PLP1 duplication and possibly for other genomic disorders.

Pleiotropic effects of sitagliptin versus voglibose in patients with type 2 diabetes inadequately controlled via diet and/or a single oral antihyperglycemic agent: a multicenter, randomized trial.

PURPOSE: A step-up strategy for diet therapy and/or single oral antihyperglycemic agent (OHA) regimens has not yet been established. The aim of this study was to evaluate hemoglobin A1c (HbA1c) as a primary end point, and the pleiotropic effects on metabolic and cardiovascular parameters as secondary end points, of sitagliptin versus voglibose in patients with type 2 diabetes with inadequate glycemic control while on diet therapy and/or treatment with a single OHA. METHODS: In this multicenter, randomized, open-label, parallel-group trial, a total of 260 patients with inadequately controlled type 2 diabetes (HbA1c levels >6.9%) were randomly assigned to receive either sitagliptin (50 mg, once daily) or voglibose (0.6 mg, thrice daily) for 12 weeks. The primary end point was HbA1c levels. RESULTS: Patients receiving sitagliptin showed a significantly greater decrease in HbA1c levels (-0.78±0.69%) compared with those receiving voglibose (-0.30±0.78%). Sitagliptin treatment also lowered serum alkaline phosphatase levels and increased serum creatinine, uric acid, cystatin-C and homeostasis model assessment-ß values. Voglibose increased low-density lipoprotein-cholesterol levels and altered serum levels of several fatty acids, and increased Δ-5 desaturase activity. Both drugs increased serum adiponectin. The incidence of adverse events (AEs) was significantly lower in the sitagliptin group, due to the decreased incidence of gastrointestinal AEs. CONCLUSIONS: Sitagliptin shows superior antihyperglycemic effects compared with voglibose as a first-line or second-line therapy. However, both agents possess unique pleiotropic effects that lead to reduced cardiovascular risk in Japanese people with type 2 diabetes. TRIAL REGISTRATION NUMBER: UMIN 000003503.

Cost-effectiveness analysis of EGFR mutation testing and gefitinib as first-line therapy for non-small cell lung cancer.

OBJECTIVES: The combination use of gefitinib and epidermal growth factor receptor (EGFR) testing is a standard first-line therapy for patients with non-small cell lung cancer (NSCLC). Here, we examined the cost-effectiveness of this approach in Japan. MATERIALS AND METHODS: Our analysis compared the 'EGFR testing strategy', in which EGFR mutation testing was performed before treatment and patients with EGFR mutations received gefitinib while those without mutations received standard chemotherapy, to the 'no-testing strategy,' in which genetic testing was not conducted and all patients were treated with standard chemotherapy. A three-state Markov model was constructed to predict expected costs and outcomes for each strategy. We included only direct medical costs from the healthcare payer's perspective. Outcomes in the model were based on those reported in the Iressa Pan-Asia Study (IPASS). The incremental cost-effectiveness ratio (ICER) was calculated using quality-adjusted life-years (QALYs) gained. Sensitivity and scenario analyses were conducted. RESULTS: The incremental cost and effectiveness per patient of the 'EGFR testing strategy' compared to the 'no-testing strategy' was estimated to be approximately JP¥122,000 (US$1180; US$1=JP¥104 as of February 2014) and 0.036 QALYs. The ICER was then calculated to be around JP¥3.38 million (US$32,500) per QALY gained. These results suggest that the 'EGFR testing strategy' is cost-effective compared with the 'no-testing strategy' when JP¥5.0 million to 6.0 million per QALY gained is considered an acceptable threshold. These results were supported by the sensitivity and scenario analyses. CONCLUSION: The combination use of gefitinib and EGFR testing can be considered a cost-effective first-line therapy compared to chemotherapy such as carboplatin-paclitaxel for the treatment for NSCLC in Japan.

Vildagliptin vs liraglutide as a second-line therapy switched from sitagliptin-based regimens in patients with type 2 diabetes: A randomized, parallel-group study.

INTRODUCTION: A step-up strategy for dipeptidyl peptidase (DPP)-4 inhibitor-based regimens has not yet been established. In addition, similarities and differences between DPP-4 inhibitors and glucagon-like peptide (GLP)-1 receptor agonists remain to be elucidated in humans. We investigated the pleiotropic effects of vildagliptin vs liraglutide in patients with type 2 diabetes on sitagliptin-based regimens in an open-label, randomized, clinical trial. MATERIALS AND METHODS: A total of 122 patients with type 2 diabetes that was inadequately controlled by sitagliptin-based regimens were randomly assigned to either vildagliptin (50 mg, twice daily) or liraglutide treatment (0.9 mg, once daily) for 12 weeks. The primary outcomes were glycated hemoglobin and body mass index. RESULTS: Both vildagliptin and liraglutide significantly lowered glycated hemoglobin within 12 weeks after switching from sitagliptin, but liraglutide produced a greater reduction (-0.67 ± 0.12% vs -0.36 ± 0.53%). Liraglutide lowered body mass index, whereas vildagliptin did not affect body mass index. Vildagliptin lowered fasting C-peptide immunoreactivity, but liraglutide did not. Vildagliptin increased serum levels of adiponectin, arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid, whereas liraglutide had no effect on these levels. Quality of life, assessed using the diabetes treatment satisfaction questionnaire, was not impaired in either group. The most common adverse events were gastrointestinal symptoms, which occurred with similar frequencies in both groups. CONCLUSIONS: Vildagliptin-mediated improvements in glycemic control did not correlate with indices for insulin secretion and insulin sensitivity. Switching from sitagliptin to liraglutide is useful in managing hyperglycemia and weight. Each agent exerts unique pleiotropic effects. This trial was registered with the University Hospital Medical Information Network Clinical Trials Registry (no. 000004953).

Behavioral and cortical EEG evaluations confirm the roles of both CCKA and CCKB receptors in mouse CCK-induced anxiety.

This study investigated the roles of cholecystokinin (CCK)(A) and CCK(B) receptors on CCK-4-induced anxiety-like behaviors in mice through behavioral and neural evaluations. Anxiety-like behaviors in mice were induced by an intracerebroventricular (i.c.v.) administration of CCK-4, which can bind to both CCK(A) and CCK(B) receptors. The effects of CCK(A) and CCK(B) receptor antagonists (devazepide and CI-988, respectively) were examined using mouse anxiety tests (elevated-plus maze and light-dark box) and also by examining neuronal activities through EEG monitoring and c-Fos immunohistochemistry in the cortex and amygdala. CCK-4 (3 µg/kg of body weight i.c.v.) significantly induced mouse anxiety-like behaviors in the anxiety tests and also affected their EEG patterns with respect to pre-drug tracing, resulting in increase in spectral power in relative power distribution in the delta and theta bands (0.5-5 Hz frequency bands) and also in increase in c-Fos immunopositive neuron counts. These CCK-4 effects were completely suppressed by 1.0mg/kg CCK(B) receptor antagonist, CI-988, while the same amount of CCK(A) receptor antagonist, devazepide was partly able to suppress the same effects. These findings indicated that not only CCK(B) receptors but also CCK(A) receptors in the brain play important roles in regulating anxiety-like behaviors in mice. The present study also proposed a possibility that cortical EEG is useful for assessing anxiety.

Synthesis and photophysical properties of zinc myoglobin appending an ethidium ion as a DNA intercalator.

In order to elucidate the intramolecular photoinduced electron-transfer or energy-transfer mechanisms of the zinc myoglobin (ZnMb) dyad and to construct a photoreaction system within a Mb-DNA complex, we newly prepared ZnMb appending an ethidium ion (Et(+)). The steady-state fluorescence of ZnMb-Et(+) at 600 nm and its lifetime (2.2 ns) indicate that the excited singlet state of (1)(ZnMb)* is not quenched by the Et(+) moiety, whereas the lifetime of the excited triplet state of (3)(ZnMb)*-Et(+) was shorter (tau = 4.3 ms) than those of ZnMb and the intermolecular (ZnMb + ethidium) system. Upon photoirradiation of Et(+), fluorescence studies indicated the intramolecular quenching reactions from the excited singlet state, (1)(Et(+))*, to ZnMb, the process of which is likely the photoinduced energy-transfer reaction via a through-space mechanism. We also demonstrate the photophysical and spectroscopic properties of ZnMb-Et(+) in the presence of calf thymus (CT) DNA. The changes in the absorption and fluorescence spectra of ZnMb-Et(+) on the addition of CT-DNA up to 15 equiv were very small, indicating that there are no major changes in the heme pocket. However, we observed a longer lifetime of (3)(ZnMb)*-Et(+) in the presence of CT-DNA (tau = 5.3 ms) by single flash photolysis. This was induced by noncovalent interactions between Et(+) and CT-DNA, followed by a conformational change of Et(+) at the surface of ZnMb, where the donor-acceptor distance was probably elongated by CT-DNA. The synthetic manipulation at the Mb surface, by using a DNA intercalator coupled with photoinduced reaction, may provide a sensitive transient signal for DNA and valuable information to construct new Mb-DNA complex.