Efficacy and safety of vildagliptin and voglibose in Japanese patients with type 2 diabetes: a 12-week, randomized, double-blind, active-controlled study.

AIM: To confirm the efficacy of vildagliptin in patients with type 2 diabetes (T2D) by testing the hypothesis that glycosylated haemoglobin (HbA1c) reduction with vildagliptin is superior to that with voglibose after 12 weeks of treatment. METHODS: In this 12-week, randomized, double-blind, active-controlled, parallel-group study, the efficacy and safety of vildagliptin (50 mg bid, n = 188) was compared with that of voglibose (0.2 mg tid, n = 192) in patients with T2D who were inadequately controlled with diet and exercise. RESULTS: The characteristics of two groups were well matched at baseline. The mean age, body mass index (BMI) and HbA1c were 59.1 years, 24.9 kg/m(2) and 7.6%, respectively. At baseline, fasting plasma glucose (FPG) and 2-h postprandial glucose (PPG) were 9.01 mmol/l (162.2 mg/dl) and 13.57 mmol/l (244.3 mg/dl), respectively. The adjusted mean change in HbA1c from baseline to endpoint was -0.95 +/- 0.04% in the vildagliptin-treated patients and -0.38 +/- 0.04% in those receiving voglibose (between-group change = 0.57 +/- 0.06%, 95% confidence interval (CI) (-0.68 to -0.46%), p < 0.001), showing that vildagliptin was superior to voglibose. Endpoint HbA1c < or = 6.5% was achieved in 51% vildagliptin-treated patients compared with 24% patients who were on voglibose (p < 0.001). Vildagliptin also exhibited significantly (p < 0.001) greater reduction compared with voglibose in both FPG [1.34 vs. 0.43 mmol/l (24.1 vs. 7.8 mg/dl)] and 2-h PPG [2.86 vs. 1.1 mmol/l (51.5 vs. 19.8 mg/dl)]. Overall adverse events (AEs) were lower in the vildagliptin-treated patients compared with that in the voglibose-treated patients (61.2 vs. 71.4%), with no incidence of hypoglycaemia and serious adverse events with vildagliptin. Gastrointestinal AEs were significantly lower with vildagliptin compared with that of the voglibose (18.6 vs. 32.8%; p = 0.002). CONCLUSIONS: Vildagliptin (50 mg bid) showed superior efficacy and better tolerability compared with voglibose in Japanese patients with T2D.

Pharmacokinetics and pharmacodynamics of vildagliptin in Japanese patients with type 2 diabetes.

OBJECTIVE: To assess the pharmacokinetics, pharmacodynamics and safety of vildagliptin, a potent and selective inhibitor of dipeptidyl peptidase IV (DPP-4), in Japanese patients with Type 2 diabetes. METHODS: In this randomized, double-blind, placebo-controlled, parallel-group study, 62 Japanese patients with Type 2 diabetes received vildagliptin 10 mg, 25 mg or 50 mg twice daily for 7 days. Blood samples were collected for the determination of plasma concentrations of vildagliptin, DPP-4, glucagon-like peptide-1 (GLP-1), glucose, insulin and glucagon. RESULTS: Exposure to vildagliptin (area under the plasma concentration-time curve from 0 to 12 h (AUC0-12h) and the maximum plasma concentration (Cmax)) increased in an approximately dose-proportional manner, and no accumulation was observed following multiple doses of vildagliptin (accumulation factor 1.00 - 1.02). DPP-4 activity was completely inhibited for varying durations by all doses of vildagliptin; the duration of complete DPP-4 inhibition was dose-dependent. DPP-4 inhibition after vildagliptin 50 mg twice daily remained > 80% throughout the 24-h period. Vildagliptin treatment led to a dose-dependent increase in plasma active GLP-1 levels; the overall increases (area under the effect-time course from 0 to 8 h, AUE0-8h) after 7 days' treatment were 1.5-, 1.7-, and 1.8-fold with vildagliptin 10 mg, 25 mg and 50 mg twice daily, respectively (all p < 0.0001 vs. placebo). Postprandial plasma glucose during the 4-h period after breakfast was significantly reduced with the 10, 25 and 50 mg vildagliptin doses by 50.3, 92.2 and 69.5 mg·h/dl, respectively. Insulin levels remained unchanged in the context of reduced glucose levels at all doses studied. CONCLUSIONS: Vildagliptin demonstrated similar pharmacokinetic and pharmacodynamic effects in Japanese patients to those observed previously in non-Japanese patients with Type 2 diabetes.

A neuroepithelial tumor showing combined histological features of dysembryoplastic neuroepithelial tumor and pleomorphic xanthoastrocytoma--a case report and review of the literature.

A neuroepithelial tumor showing combined histological features of dysembryoplastic neuroepithelial tumor (DNT) and pleomorphic xanthoastrocytoma (PXA) is described. The patient was a 60-year-old male with a long-standing temporal lobe tumor and seizures. After a long, dormant period, the tumor, which had been localized in the left uncus, re-grew rapidly and extended into the subarachnoidal space and brain stem. The post-operative specimens disclosed two distinct components: an intra-cortical, cystic lesion containing mucinous materials and an extra-cortical, nodular lesion involving the leptomeninges. The former contained oligodendroglia-like small, round cells placed along axonal processes, plus mature neurons situated against mucinous materials (DNT-like component, WHO Grade I). The latter contained spindle and/or pleomorphic cells expressing glial fibrillary acidic protein, having bizarre nuclei and atypical mitotic figures. A reticulin network was developed among the tumor cells (PXA-like component, WHO Grade III). This case illustrates an unusual composite brain tumor, combined DNT and PXA.

Liver-related safety assessment of green tea extracts in humans: a systematic review of randomized controlled trials.

There remain liver-related safety concerns, regarding potential hepatotoxicity in humans, induced by green tea intake, despite being supposedly beneficial. Although many randomized controlled trials (RCTs) of green tea extracts have been reported in the literature, the systematic reviews published to date were only based on subjective assessment of case reports. To more objectively examine the liver-related safety of green tea intake, we conducted a systematic review of published RCTs. A systematic literature search was conducted using three databases (PubMed, EMBASE and Cochrane Central Register of Controlled Trials) in December 2013 to identify RCTs of green tea extracts. Data on liver-related adverse events, including laboratory test abnormalities, were abstracted from the identified articles. Methodological quality of RCTs was assessed. After excluding duplicates, 561 titles and abstracts and 119 full-text articles were screened, and finally 34 trials were identified. Of these, liver-related adverse events were reported in four trials; these adverse events involved seven subjects (eight events) in the green tea intervention group and one subject (one event) in the control group. The summary odds ratio, estimated using a meta-analysis method for sparse event data, for intervention compared with placebo was 2.1 (95% confidence interval: 0.5-9.8). The few events reported in both groups were elevations of liver enzymes. Most were mild, and no serious liver-related adverse events were reported. Results of this review, although not conclusive, suggest that liver-related adverse events after intake of green tea extracts are expected to be rare.

2,3,5-Trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1,4-benzoquinone (AA861), a selective inhibitor of the 5-lipoxygenase reaction and the biosynthesis of slow-reacting substance of anaphylaxis.

2,3,5-Trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1,4-benzoquinone (AA861) inhibited 5-lipoxygenase of guinea pig peritoneal polymorphonuclear leukocytes (ID50, 0.8 microM). The inhibition was of competitive type. 12-Lipoxygenases and fatty acid cyclooxygenase were not affected below 10 microM. The formation of slow-reacting substance of anaphylaxis by the sensitized guinea pig lung was almost fully suppressed by the compound at 10 microM.

Enzyme immunoassay of thromboxane B2.

An immunoassay for thromboxane B2 was developed in which the hapten molecule was labeled with beta-galactosidase. The immunoprecipitate formed after competition between enzyme-labeled and unlabeled thromboxane B2 was subjected to a fluorometric assay of beta-galactosidase. Thromboxane B2 was detectable in the range of 0.1-30 pmol. Both enzyme immunoassay and radioimmunoassay showed essentially the same cross-reactivities with other prostaglandins and their metabolites when the same antibody was used. Known amounts of thromboxane B2 were added to human plasma, and the sample was applied to an octadecyl silica column. The extract was analyzed by enzyme immunoassay to examine the correlation between the added (x) and measured (y) thromboxane B2 (y = 1.09x + 11.07 pmol/ml, r = 0.99). A satisfactory correlation was observed between radioimmunoassay (x) and enzyme immunoassay (y) (y = 0.92x + 4.64 pmol/ml, r = 0.96). The validity of enzyme immunoassay was also confirmed by gas chromatography-mass spectrometry of a dimethylisopropylsilyl ether derivative of thromboxane B2 methyl ester. The method was applicable to the assay of thromboxane B2 produced from endogenous precursor during thrombin-induced aggregation of human platelets.

Selective loss of small myelinated fibers in the lateral corticospinal tract due to midbrain infarction.

Small myelinated fibers in the lateral corticospinal tract (LCST) were selectively diminished as compared with large myelinated fibers in a patient with an old paramedian midbrain infarct involving the red nuclei, oculomotor nuclei, and inferior olivary pseudohypertrophy. Although the physiologic function of small myelinated fibers in the LCST is unknown in humans, we hypothesize that some of these fibers may include the rubrospinal tract.

Axonal pathology in Japanese Guillain-Barré syndrome: a study of 15 autopsied cases.

We assessed the frequency and extent of axonal involvement in the ventral spinal roots in 15 Japanese autopsied patients with Guillain-Barré syndrome (GBS). Teased-fiber preparation revealed that five had predominantly axonal pathology with minimal segmental demyelination, seven had predominantly segmental demyelination with minimal axonal changes, two patients showed a mixture of both conditions, and one patient did not show any particular pathologic changes. We confirmed axon loss by immunohistochemical analysis of high-molecular-weight neurofilament protein. Macrophage invasion was a prominent feature in nerves with predominantly axonal changes. Two patients with severe axonal involvement and prolonged clinical courses exhibited motor neuron loss with astrogliosis in the ventral horns. These results suggest that autopsy-verified axonal involvement is more frequent among Japanese GBS patients than in Caucasian populations but less frequent than that reported from northern China.

Modeling of human thromboxane A2 receptor and analysis of the receptor-ligand interaction.

In order to elucidate the mode of the thromboxane A2 (TXA2) receptor-ligand interaction at the molecular level, a model for the human TXA2 receptor, a member of the G protein-coupled receptor family with seven transmembrane segments, was constructed on the basis of its amino acid sequence, which was determined recently (Hirata, M.; et al. Nature 1991, 349, 617-620). First, we made a model for the human beta 2-adrenergic receptor using its amino acid sequence and the known helix arrangement of bacteriorhodopsin. Then, a TXA2 receptor model was constructed based on the beta 2 receptor model and was used to analyze the receptor-ligand interaction. The ligand-binding pocket of the TXA2 receptor includes a serine residue from segment V, an arginine residue from segment VII, and a large hydrophobic pocket between these two residues. These results are consistent with the known properties of TXA2 and TXA2 antagonists having a hydrogen-bonding group such as hydroxyl, a carboxyl group, and a hydrophobic moiety. This model should be helpful for rational design of potent TXA2 antagonists.

Studies on scavengers of active oxygen species. 1. Synthesis and biological activity of 2-O-alkylascorbic acids.

A novel series of 2-O-alkylascorbic acids (5a-u) was synthesized, and their scavenging activities against active oxygen species as well as their suppressive effects on the arrhythmias in rat heart ischemia-reperfusion models were evaluated. Some 2-O-alkylascorbic acids (5e-1) exhibited potent inhibiting activities against lipid peroxidation in rat brain homogenates and in alleviating effects in the ischemia-reperfusion models. Studies on the structure-activity relationship demonstrated that a free 3-enolic hydroxyl group and the longer alkyl chains substituted on the 2-hydroxyl group of ascorbic acid were beneficial for the biological and pharmacological activities. 2-O-Octadecylascorbic acid (5k, CV-3611), one of the most potent and promising compounds, markedly inhibited lipid peroxidation (IC50 = 4.3 X 10(-6) M) and alleviated myocardial lesions induced by ischemia-reperfusion at an oral dose of 1 mg/kg in rats.

Thromboxane synthetase inhibitors (TXSI). Design, synthesis, and evaluation of a novel series of omega-pyridylalkenoic acids.

A novel series of omega-pyridylalkenoic acids has been prepared by applying the Wittig reaction. Modifications were made in the omega-aryl moiety, the alkylene chain length, the alpha-methylene group adjacent to the carbonyl group, and the carboxyl group of the molecule. The compounds were tested as inhibitors of thromboxane synthetase in an in vitro assay and in ex vivo experiments with the rat. Most members of this new class of thromboxane synthetase inhibitors (TXSI) showed good activity in both assay systems. (E)-7-Phenyl-7-(3-pyridyl)-6-heptenoic acid (9c; CV-4151) was one of the most potent compounds in in vitro enzyme inhibition (IC50 = 2.6 X 10(-8) M) and, when orally administered, the most potent and long acting in the inhibition of blood thromboxane A2 production in the rat. New conceptual models I-III for the enzyme-substrate (prostaglandin H2, PGH2) and the enzyme-TXSI interactions are proposed for understanding the molecular design and structure-activity relations.

Dual inhibitors of thromboxane A2 synthase and 5-lipoxygenase with scavenging activity of active oxygen species. Synthesis of a novel series of (3-pyridylmethyl)benzoquinone derivatives.

A novel series of (3-pyridylmethyl)benzoquinone derivatives was molecular designed and synthesized for the dual purpose of inhibiting thromboxane A2 and leukotriene biosynthesis enzymes and scavenging active oxygen species (AOS). They were evaluated for inhibition of TXA2 synthase, inhibition of 5-lipoxygenase, and for their scavenging activity of AOS using the thiobarbituric acid method. 2,3,5-Trimethyl-6-(3-pyridylmethyl)-1,4-benzoquinone (24, CV-6504) was the most promising derivative since it showed efficient AOS scavenging activity (inhibition of lipid peroxidation in rat brain homogenates: IC50 = 1.8 x 10(-6) M) as well as potent, specific, and well-balanced inhibitory effects on both enzymes (inhibitory effect on TXA2 synthase in human blood, IC50 = 3.3 x 10(-7) M; inhibitory effect on 5-lipoxygenase in human blood, IC50 = 3.6 x 10(-7) M). In adriamycin-induced proteinuria in a rat model, compound 24 at 10 mg/kg per day (po) suppressed proteinuria by more than 50%. The proteinuria, however, could not be reduced by single administration of an inhibitor specific for thromboxane A2 synthase [(E)-7-phenyl-7-(3-pyridyl)-6-heptenoic acid (2, CV-4151)] or for 5-lipoxygenase [2-(12-hydroxy-5,10-dodecadiynyl)-3,5,6-trimethyl-1,4-benzoquinone (1, AA-861)]. The proteinuria was also not reduced by administration of an AOS scavenger, 2-O-octadecylascorbic acid (4, CV-3611). Triple function compounds such as compound 24 that specifically inhibit both enzymes as well as scavenge AOS possess a variety of pharmacologically beneficial effects.

Quinones. 4. Novel eicosanoid antagonists: synthesis and pharmacological evaluation.

A new series of omega-phenyl-omega-quinonylalkanoic acids and related compounds was synthesized. The compounds were tested for their inhibitory effects on U-44069-induced contraction of the rabbit aorta. (+/- )-7-(3,5,6-Trimethyl-1,4-benzoquinon-2-yl)-7-phenylheptanoic acid (4d) (AA-2414) with pA2 value of 8.28 was one of the most potent compounds. Compound 4d inhibited U-46619-induced contraction of the guinea pig lung (pA2 = 8.29) and U-44069-induced aggregation of the guinea pig platelet (IC50 = 3.5 x 10(-7) M). Compound 4d displaced the binding of [3H]U-46619 to guinea pig platelets (IC50 = 7.4 x 10(-9) M). Compound 4d also showed very potent inhibitory effects with an MED of 0.3 mg/kg (po) on U-46619-, LTD4-, PAF-, or IgG1-induced bronchoconstriction in guinea pigs. The enantiomers of 4d were prepared. The R-(+) isomer 8a was active in both in vitro and in vivo tests, but the S-(-) isomer 8b was much less active. We concluded that the antiasthmatic effects of 4d were based mainly on the TXA2 receptor antagonistic action. In addition, compound 4d showed potent inhibitory effects on PGD2-, PGF2 alpha-, and 11-epi-PGF2 alpha-induced contraction of the guinea pig tracheal strips. The diverse inhibitory effects might be expressed in terms of eicosanoid-antagonistic activity.

Slow intrinsic optical signals in the rat spinal dorsal horn in slice.

Tetanic stimulation of high-threshold primary afferent fibers in the dorsal root was found to elicit intrinsic optical signals (IOSs) in transverse slices of 11- to 20-day-old rat spinal cords. The IOS, lasting for 30 s or longer, was most prominent in the lamina II of the dorsal horn. Treatment with a Na+-K+-2Cl- co-transport blocker, furosemide, abolished the IOS, suggesting that the origin of the IOS is the cellular swelling due to an activity-dependent rise in extracellular K+. Substance P antagonist spantide, glutamate antagonists 2-amino-5-phosphonovaleric acid and 6-cyano-7-nitroquinoxaline-2,3-dione, and the mu-opioid agonist [d-Ala2,N-Me-Phe4,Gly5-ol]-enkephalin suppressed IOSs. Thus, IOSs represent at least in part the slow excitatory response that is known to be generated in dorsal horn neurons after tetanic activation of unmyelinated afferent fibers.

Acquired idiopathic generalized anhidrosis: a distinctive clinical syndrome.

The present study concerns a 28-year-old Japanese man with acquired generalized anhidrosis. The patient's ability to perspire was investigated in an artificial climate room maintained at 40 degrees C and 40% humidity. Although the body temperature rose to 38 degrees C, the patient did not sweat. Neither did sweating occur when the patient was given an intradermal injection of pilocarpine or nicotine. The serum IgE level was elevated. Atrophy and degeneration of the sweat glands, as well as infiltration by lymphocytes and mast cells around the sweat glands, were observed in skin biopsies. Anhidrosis in this patient was suggested to be the result of reduced function of the sweat glands themselves with possible underlying immune-mediated basis.

Disease-specific patterns of neuronal loss in the spinal ventral horn in amyotrophic lateral sclerosis, multiple system atrophy and X-linked recessive bulbospinal neuronopathy, with special reference to the loss of small neurons in the intermediate zone.

The ventral horn cells of the fourth lumbar segment were morphometrically analysed in six cases of amyotrophic lateral sclerosis (ALS; there common forms and three pseudopolyneuritic forms), six of multiple system atrophy (MSA) with autonomic failure, four of X-linked recessive bulbospinal neuronopathy (X-BSNP), and seven age-matched autopsy cases of non-neurological disorders. In the common form of ALS, large and medium-sized neurons of the medial and lateral nuclei were markedly lost; small neurons in the intermediate zone were slightly diminished but fairly well preserved. In the pseudopolyneuritic form of ALS, marked loss was present in the large and medium-sized neurons, and in the small neurons located in the intermediate zone as well. In the MSA, in contrast to ALS, there was a marked reduction in small neurons in the intermediate zone, and large and medium-sized neurons of the medial and lateral nuclei tended to be preserved. In X-BSNP, large and medium-sized neurons were almost completely lost and small neurons were also markedly depopulated. These findings indicated that the pattern of neuron loss in the ventral horn is distinct among these diseases depending on size, location and function of the ventral horn cell population. These disease-specific patterns of neuron loss suggest a difference in the process of neuronal degeneration of ventral horn cells among the disease examined.

Expression of glial cell line-derived growth factor mRNA in the spinal cord and muscle in amyotrophic lateral sclerosis.

The steady-state expression levels of glial cell line-derived growth factor (GDNF) mRNA was studied in the post mortem spinal cord and muscle of patients with amyotrophic lateral sclerosis (ALS), by reverse transcription followed by polymerase chain reaction (RT-PCR). GDNF mRNA levels in the lumbar cord were significantly increased in ALS as compared with controls. On the other hand, GDNF mRNA levels were significantly lower in the muscle in ALS patients. The increase of GDNF mRNA in the spinal cord mostly reflected an increase in the anterior horn, anterior and lateral columns, where the pathological involvement was severe. In the posterior column and posterior horn with less pathological involvement, the increase was less. These results suggest that GDNF mRNA levels are inversely regulated between the spinal cord and muscle in ALS, increased in the spinal cord and lowered in the muscle, in correlation with the pathological severity.

CV-4151--a potent, selective thromboxane A2 synthetase inhibitor.

(E)-7-Phenyl-7-(3-pyridyl)-6-heptenoic acid (CV-4151) inhibited horse platelet microsomal thromboxane (TX) A2 synthetase with an IC50 of 2.6 X 10(-8) M, but even at a high concentration of 10(-4) M it had little effect on cyclooxygenase, PGI2 synthetase and 5-lipoxygenase in in vitro enzymatic assays. CV-4151 did not affect PGI2 release from rat and rabbit aortic tissues in in vitro (10(-4) M) and ex vivo (10 and 100 mg/kg, p.o.) experiments, whereas aspirin (10(-4) M or 10 and 100 mg/kg, p.o.) markedly inhibited PGI2 release in these preparations. When given orally to rats and dogs, CV-4151 markedly inhibited blood TXA2 synthetase activity: the ID50 values (mg/kg, 2 hr later) were 0.05 in rats and 0.17 in dogs. The inhibitory effects at an oral dose of 1 mg/kg lasted more than 24 hr in both species; the inhibition was 41% in rats and 32% in dogs 24 hr after the administration. When injected i.v. to rats and dogs, CV-4151 caused inhibitory effects on TXA2 synthetase equipotent to those observed with the oral administration. In both species, CV-4151 given orally increased concentration of serum immunoreactive 6-keto-PGF1 alpha concomitant with a decrease of serum TXB2-8 concentration. CV-4151 was equipotent to OKY-1580 (IC50: 2.3 X 10 M), a well documented TXA2 synthetase inhibitor, in an in vitro TXA2 synthetase assay. However, CV-4151, given orally or i.v. to rats and dogs, was much more potent and longer acting in inhibition of blood TXA2 production than OKY-1580. Dazoxiben was less potent than these compounds in vitro. In rats, serial oral administration of CV-4151 (10 mg/kg) once daily for 14 days produced a constant and marked reduction of serum TXB2 concentration with concomitant increase of serum immunoreactive 6-keto-PGF1 alpha concentration. No rebound phenomenon in inhibition of TXA2 synthetase was observed after the dosing was stopped. These findings indicate that CV-4151 is a potent and long acting selective inhibitor of TXA2 synthetase and may reorient the metabolism of PG endoperoxides to PGI2.

Somatic motor efferents in multiple system atrophy with autonomic failure: a clinico-pathological study.

The myelinated fibers in the corticospinal tracts, ventral spinal roots, and the neurons in the ventral spinal horns were quantitatively examined in 8 autopsied cases of multiple system atrophy associated with autonomic failure. In these structures consisting of the somatic motor efferents, the main pathological feature was the size dependent-involvement of predominantly small-sized fibers and neurons. The small myelinated fibers were significantly depopulated, while the large myelinated fibers were well populated in the corticospinal tract. Neurons in the ventral horns were also involved, but those with a small diameter and located in the intermediate zone (Rexed's lamina VII, VIII) were markedly diminished. In the ventral spinal roots, in the fourth lumbar segments containing essentially no autonomic efferents, small myelinated fibers were also preferentially involved. These pathological changes in the small-sized fiber and neuron loss were examined in relation to the somatic and autonomic motor symptoms, particularly of pyramidal signs.

Magnetic resonance imaging of the corticospinal tracts in amyotrophic lateral sclerosis.

In 13 patients with amyotrophic lateral sclerosis (ALS), corticospinal tract lesions on spinal cord, brain and brain stem were examined by MR imaging. In 9 patients, areas of high signal intensity located in the dorsolateral columns coinciding with the lateral corticospinal tracts, were detected on axial T2*-weighted MR imaging of the cervical spinal cord using a gradient echo technique. In two patients, these spinal cord MR abnormalities corresponded well to the postmortem pathological findings of lateral corticospinal tract degeneration. T2-weighted abnormal MR signals along the corticospinal tract at the brain and brain stem were detected in 4 patients, all of whom also showed abnormal signals on cervical cord MR imaging. Four of 13 patients did not show any abnormal signals on brain and brain stem or spinal cord MR imaging. Spinal cord MR imaging provides a useful information regarding upper motor neuron lesions in ALS.