Vascular Functional and Morphological Alterations in Smokers during Varenicline Therapy

BACKGROUND

Varenicline has been reported to achieve high rates of smoking cessation. It remains undetermined whether varenicline therapy improves vascular function in smokers.

METHODS

Consecutive Seventy-two smokers (age 57 ± 12 years) who succeeded in complete smoking cessation and 46 normal healthy volunteers (age 24 ± 3 years) with no cardiovascular risk factors were enrolled into this study. Vascular function and structure were assessed by flow-mediated dilation (FMD), nitroglycerin-induced vasodilation, and brachial artery intima-media thickness (baIMT) at baseline and 20 weeks after the initiation of varenicline therapy in smokers. FMD and baIMT were measured simultaneously using a semi-automatic vessel wall-tracking software program. 75 μg dose of a nitroglycerin tablet were sublingually administered for the nitroglycerin-induced vasodilation measurement.

RESULTS

Exhaled-carbon monoxide concentration decreased significantly (20.0 ± 11.1 ppm at baseline vs 1.9 ± 1.5 ppm after 20 weeks, p < 0.001). FMD was significantly improved after 20 weeks (4.09% ± 1.83% at baseline vs 4.77% ± 2.33% after 20 weeks, p = 0.010), whereas nitroglycerin-induced vasodilation and baIMT were not significantly changed.

CONCLUSIONS

Smoking cessation with varenicline therapy significantly increased FMD without significant changes of nitroglycerin-induced vasodilation or baIMT from baseline to 20 weeks. It appears to improve vascular function in smokers, which depends on endothelial function rather than on vascular smooth muscle function or changes in vascular structure.

In situ detection and identification of hesperidin crystals in satsuma mandarin (Citrus unshiu) peel cells

INTRODUCTION

Hesperidin, a flavonoid known to have important pharmacological effects, accumulates particularly in the peels of satsuma mandarin (Citrus unshiu). Although histochemical studies have suggested that hesperidin forms crystals in some tissues of the Rutaceae and Umbelliferae, there has been no rigorous in situ detection or identification of hesperidin crystals in C. unshiu.

OBJECTIVE

To characterise the chemical component of the crystals found in C. unshiu peels using Raman microscopy.

METHODS

Sections of C. unshiu peels were made. The distribution and morphology of crystals in the sections were analysed microscopically. Raman microscopy was used to detect hesperidin in the sections directly.

RESULTS

The crystals were more abundant in immature peel and were observed particularly in areas surrounding vascular bundles, around the border between the flavedo and albedo layers and just below the epidermal cells. In the morphological analysis by scanning electron microscopy, needle-shaped crystals aggregated and formed clusters of spherical crystals. Spectra obtained by Raman microscopy of the crystals in the peel sections were consistent with those of the hesperidin standard.

CONCLUSION

This study showed the detailed distribution of crystals in C. unshiu peels and their main component was identified using Raman microscopy to be hesperidin for the first time.

Preparation and characterization of a transparent amorphous cellulose film

Amorphous cellulose film (ACF) was prepared from cellulose solution in lithium chloride (8 wt%)/N,N-dimethylacetamide by regeneration with acetone.

Future of pharmacogenetics-based therapy for tuberculosis

Personalized medicine uses technology to enable a level of personalization not previously practical. Currently, tuberculosis (TB) therapy is not personalized. Previous reports have shown that a genetic polymorphism of NAT2 is associated with large interindividual and inter-racial differences in the toxicity and efficacy of isoniazid. Herein, we show the safety and efficacy of a pharmacogenetics-based standard TB therapy and also provide a schematic presentation that proposed therapeutic approaches for latent TB infection (LTBI) using NAT2 genotyping. Our data show that the pharmacogenetics-based TB therapy is safer and more efficacious than the standard therapy. Therefore, the therapy using NAT2 genotyping proposed for LTBI herein will be safer and more efficacious than the standard LTBI therapy. Introduction of this therapy with NAT2 genotyping will be one of the cornerstones of personalized medicine.

Role of protein phosphorylation in excitation-contraction coupling in taurine deficient hearts

Taurine is a beta-amino acid found in very high concentration in the heart. Depletion of these intracellular stores results in the development of cardiomyopathy, thought to be mediated by abnormal sarcoplasmic reticular (SR) Ca(2+) transport. There is also evidence that taurine directly alters the Ca(2+) sensitivity of myofibrillar proteins. Major regulators of SR Ca(2+) ATPase (SERCA2a) are the phosphorylation status of a regulatory protein, phospholamban, and SERCA2a expression, which are diminished in the failing heart. The failing heart also exhibits reductions in myofibrillar Ca(2+) sensitivity, a property regulated by the phosphorylation of the muscle protein, troponin I. Therefore, we tested the hypothesis that taurine deficiency leads to alterations in SR Ca(2+) ATPase activity related to reduced phospholamban phosphorylation and expression of SERCA2a. We found that a sequence of events, which included elevated protein phosphatase 1 activity, reduced autophosphorylation of CaMKII, and reduced phospholamban phosphorylation, supports the reduction in SR Ca(2+) ATPase activity. However, the reduction in SR Ca(2+) ATPase activity was not caused by reduced SERCA2a expression. Taurine transporter knockout (TauTKO) hearts also exhibited a rightward shift in the Ca(2+) dependence of the myofibrillar Ca(2+) ATPase, a property that is associated with an elevation in phosphorylated troponin I. The findings support the observation that taurine deficient hearts develop systolic and diastolic defects related to reduced SR Ca(2+) ATPase activity, a change mediated in part by reduced phospholamban phosphorylation.

Two cytosolic aldolases show different expression patterns during shoot elongation in Moso bamboo, Phyllostachys pubescens Mazel

In fast-growing Moso bamboo (Phyllostachys pubescens Mazel), cytosolic fructose 1,6-bisphosphate aldolase (aldolase; EC 4.2.2.13) was more highly active in elongating tissues than in tissues that had already finished elongating. It is well known that the removal of the culm sheath prevents bamboo from elongating. When the sheath was removed from the culm, the aldolase activity was gradually reduced over time. Two isozyme genes for aldolase, PpAldC1 and PpAldC2, were cloned from the elongating tissues of Moso bamboo. Gene expression analysis using a semi-quantitative reverse transcriptase-polymerase chain reaction revealed that PpAldC1 was highly expressed in elongating tissues but was hardly detected in elongated internodes, while PpAldC2 seemed to be expressed constitutively in both elongating and elongated tissues. Promoter analysis revealed that the expression of PpAldC1 was induced by gibberellin. These results indicated that the two genes for cytosolic aldolase in Moso bamboo showed different expression patterns and that one of them was involved in shoot elongation.

Cuticular membrane of Fuyu persimmon fruit is strengthened by triterpenoid nano-fillers

The mechanical defensive performance of fruit cuticular membranes (CMs) is largely dependent on the molecular arrangement of their constituents. Here, we elucidated nano-sized interactions between cutin and triterpenoids in the cuticular matrix of Fuyu persimmon fruits (Diospyroskaki Thunb. cv. Fuyu), focusing on the mechanical properties using a combination of polymer analyses. The fruit CMs of Fuyu were primarily composed of wax (34.7%), which was predominantly triterpenoids followed by higher aliphatic compounds, and cutin (48.4%), primarily consisting of 9,10-epoxy-18-hydroxyoctadecanoic acid and 9,10,18-trihydroxyoctadecanoic acid. Based on the tensile tests of the CM, the removal of wax lead to a considerable decrease in the maximum stress and elastic modulus accompanied by an increase in the maximum strain, indicating that wax is of significant importance for maintaining the mechanical strength of the CM. Wide-angle X-ray diffraction and relaxation time measurements using solid-state (13)C nuclear magnetic resonance indicated that the triterpenoids in the cuticular matrix construct a nanocomposite at a mixing scale below 20-24 nm; however, the higher aliphatic compounds did not exhibit clear interactions with cutin. The results indicated that the triterpenoids in the cuticular matrix endow toughness to the CM by functioning as a nanofiller.

Microwave-assisted hydrolysis of polysaccharides over polyoxometalate clusters

Polyoxometalate (POM) clusters were utilized as recyclable acid catalysts and microwave-absorbing agents for the microwave-assisted hydrolysis of corn starch and crystalline cellulose. Phosphotungstic (PW) and silicotungstic (SiW) acids showed high hydrolyzing activity, while phosphomolybdic acid (PMo) showed lower glucose stability. The PW catalyst could be recycled by ether extraction at least 4 times without changing its catalytic activity. The addition of PW could reduce the energy demand required for running the hydrolysis by 17-23%. The dielectric property of the aqueous PW solution was important for increasing the microwave-absorption capability of the reaction system and reducing the energy consumption.

Pharmacokinetics of a Single 150-mg Intravenous Infusion of Fosaprepitant: Effects of Concentration and Infusion Time in Healthy Japanese Men

PURPOSE

Fosaprepitant dimeglumine (Proemend® for Injection; formerly ONO-7847) is a phosphorylated prodrug that is rapidly converted to aprepitant, an oral selective neurokinin-1 receptor antagonist approved for the prevention of chemotherapy-induced nausea and vomiting. This Phase 1 study evaluated the pharmacokinetics, safety, and tolerability of fosaprepitant after a single intravenous dose in healthy Japanese men.

METHODS

All fosaprepitant- or placebo-treated subjects were assessed for the occurrence of adverse events.

RESULTS

Ninety subjects were randomized into treatment and placebo groups. The plasma fosaprepitant concentrations generally reached steady state by 15 minutes after the start of infusion. Although the maximum concentration was proportional to the infusion time, no clinically important pharmacokinetic differences were noted in the cohorts examined. Most adverse events observed in this study were associated with infusion site reactions, which tended toward a higher incidence with shorter infusion times. These events were mild in severity.

CONCLUSIONS

These findings demonstrate that fosaprepitant at different concentrations and over different infusion times has a pharmacokinetic and safety profile that is comparable to the intravenous dose previously established as efficacious and well tolerated. The dosing flexibility afforded by the single-dose fosaprepitant formulation should lead to greater convenience for patients and health care providers.

Polymorphisms of CYP2D6 gene and gefitinib-induced hepatotoxicity

INTRODUCTION

Gefitinib induces severe hepatotoxicity in approximately a quarter of Japanese patients with epidermal growth factor receptor (EGFR) mutation-positive non-small-cell lung cancer (NSCLC). Gefitinib is metabolized by cytochrome P450 (CYP) enzymes--including CYP3A4/5, CYP1A1, and CYP2D6--in the liver. We hypothesized that polymorphisms of the CYP2D6 gene may account for gefitinib-induced hepatotoxicity.

PATIENTS AND METHODS

Polymorphisms of the CYP2D6 gene were analyzed in 55 patients with NSCLC who experienced grade ≥ 2 transaminase elevation from gefitinib. The distribution of the CYP2D6 genotype was compared with that of the healthy Japanese population. The correlations between the nonfunctional allele *5 or the reduced-function allele *10 and hepatotoxicity-related clinical factors were also examined.

RESULTS

The distribution of the CYP2D6 genotype in the study participants was not different from that of the general Japanese population, reported previously. Existence of allele *5 or *10 did not correlate with clinical factors such as onset of hepatotoxicity within 2 months, grade ≥ 3 serum transaminase elevation, and tolerability to dose reduction or rechallenge of gefitinib. However, in 7 patients taking CYP3A4-inhibitory drugs, rechallenge of gefitinib again caused hepatotoxicity in 4 patients with allele *5 or *10 but not in 3 patients with normal alleles (P = .029). Moreover, switching to erlotinib did not cause hepatotoxicity in any of 17 patients with allele *5 or *10 but did in 3 of 8 patients without these alleles (P = .024).

CONCLUSION

Reduced function of CYP2D6 may partly account for gefitinib-induced hepatotoxicity when CYP3A4 is inhibited. Erlotinib could be safely used in patients with decreased CYP2D6 activity even after they experienced gefitinib-induced hepatotoxicity.

Total fractionation of green tea residue by microwave-assisted alkaline pretreatment and enzymatic hydrolysis

Total refinery of constituents of green tea residue was achieved by combination of microwave-assisted alkaline pretreatment and enzymatic hydrolysis. Alkaline pretreatment was effective at separating pectic polysaccharides, protein, phenolic compounds and aliphatic compounds (probably originating from cuticular components), and the solubilization rate was attained 64–74% by heating at 120–200 °C. The higher heating value (HHV) of alkali-soluble fraction attained 20.1 MJ/kg, indicating its usability as black-liquor-like biofuel. Successive cellulolytic enzymatic hydrolysis mainly converted cellulose into glucose and attained the maximum solubilization rate of 89%. Final residue was predominantly composed of aliphatic cuticular components with high proportion in 9,10,18-trihydroxyoctadecanoic acid (30.1–48.6%). These cuticular components are potential alternative feedstock for aliphatic compounds commonly found in oil plants.

Repeated-dose pharmacokinetics of inhaled ciclesonide (CIC-HFA) in Japanese children with bronchial asthma: a phase I study

BACKGROUND

Ciclesonide (CIC) is a highly safe, inhaled corticosteroid (ICS) that is converted into a pharmacologically active metabolite (des-isobutyryl-ciclesonide); this metabolite, in turn, exerts a local anti-inflammatory effect on lung tissue. The present study was undertaken to analyze the pharmacokinetics of des-isobutyryl-ciclesonide in the serum of Japanese children with bronchial asthma treated by repeated doses of CIC and to compare the data thus obtained with those obtained for Caucasian children with bronchial asthma.

METHODS

Eight Japanese children with bronchial asthma were treated for 7 days with CIC-hydrofluoroalkalane (CIC-HFA) 200 μg/day administered by a metered-dose inhaler. The study was designed to assess the pharmacokinetics after 7-day repeated administration by which the steady state can be achieved, based on the results of an earlier study involving healthy Japanese adult males who received 7-day repeated administration of CIC-HFA. Blood was sampled at multiple time points on Day 7 of treatment for measurement of the serum des-isobutyryl-ciclesonide level.

RESULTS

The pharmacokinetic parameters (AUC from time zero to last observed concentration [AUC(t)], AUC over the dosage interval τ at steady state [AUC(ss)], maximum concentration [C(max)], and terminal elimination half-life [T(1/2)]) and the temporal changes in the serum levels of des-isobutyryl-ciclesonide after repeated administration of CIC-HFA (200 μg/day) in Japanese children with bronchial asthma differed only slightly from those in Caucasian children with bronchial asthma. No serious adverse events were noted during the study period. Additionally, no abnormalities were detected in the serum cortisol level, other laboratory parameters, or vital signs.

CONCLUSIONS

Our results suggest that there is little difference in the pharmacokinetics of des-isobutyryl-ciclesonide up on repeated administration of CIC-HFA between Japanese and Caucasian children with bronchial asthma. And our study suggests that CIC-HFA (200 μg/day, once daily) can be administered safely for 7 days, without raising any safety concerns.

Compositional analysis of leaf cuticular membranes isolated from tea plants (Camellia sinensis L.)

Chemical constituents of cuticular membranes (CMs) isolated from three tea cultivars (Camellia sinensis (L.) O. Kuntze cvs. Yabukita, Samidori and Gokou) were compared. All CMs from the adaxial side of the leaves showed higher accumulation of wax, cutin and polysaccharide, while those from the abaxial side were abundant in cutan, showing the adaptation of the adaxial side to abiotic stresses, such as wind and rain, in contrast to the abaxial side, which provides defence against pathogens. Yabukita, a major tea cultivar in Japan, developed thick CMs while Samidori and Gokou, shade-cultivated tea cultivars, had lighter CMs, reflecting their thin and soft leaves. CMs rapidly accumulated 9,10-epoxy-18-hydroxyoctadecanoic acid at a very early stage of leaf development. Additionally, shade treatment did not influence cutin biosynthesis in CMs, reflecting high adaptation of tea leaves under low light levels.

Genome-wide association study of SSRI/SNRI-induced sexual dysfunction in a Japanese cohort with major depression

Sexual dysfunction is a major side effect of selective serotonin reuptake inhibitors (SSRIs) and serotonin-noradrenaline reuptake inhibitors (SNRIs). We conducted a genome-wide association study to identify the genetic factors contributing to the risk of SSRI/SNRI-induced sexual dysfunction by testing 186 320 single nucleotide polymorphism (SNP) markers in a cohort of 201 Japanese major depression patients including 36 with sexual dysfunction induced by SSRI (paroxetine or fluvoxamine) or SNRI (milnacipran). The Cochran-Armitage trend test showed that 11 SNPs, tightly clustered in a distinct region on chromosome 14q21.3, were associated with SSRI/SNRI-induced sexual dysfunction at a genome-wide significance level after false discovery rate (FDR) correction, and the strongest SNP association was with rs1160351 (P=3.04 × 10(-7), risk ratio=2.92, 95% confidence interval (CI)=1.79-4.76). These SNPs mapped to the intronic region of the MDGA2 gene. A Manhattan plot showed that the strong association peak remained in MDGA2 after adjustment for sex and age in a multivariable logistic regression analysis although P values increased slightly and became non-significant. Replication studies with larger sample sizes are required to validate this exploratory study, but our findings may provide insights into the genetic basis of sexual dysfunction induced by SSRI/SNRI.

Andrographolide inhibits the expression and metabolic activity of cytochrome P450 3A4 in the modified Caco-2 cells

AIM OF THE STUDY

The aim of this study is to examine the effects of andrographolide on intestinal enzyme cytochrome P450 3A4 (CYP3A4) and predict whether oral administration of andrographolide-containing remedy leads to herb-drug interaction.

MATERIALS AND METHODS

Caco-2 cells are treated with 1α, 25-dihydroxyvitamin D3 for 3 wks to induce the expression of CYP3A4, and then andrographolide (1, 10, 100 μM) is added and treated for 72 h. Upon the further 4-h testosterone (250 μM) or nifedipine (200 μM) treatment, the basolateral medium samples and the Caco-2 monolayers are collected for analyses.

RESULTS

Andrographolide (1, 10, 100 μM) significantly down-regulates the mRNA level and protein level of CYP3A4, and inhibits nifedipine oxidation and testosterone 6β-hydroxylation.

CONCLUSION

Oral administration of andrographolide likely leads to reduction of the metabolic activity of intestinal CYP3A4, therefore herb preparations containing andrographolide may result to herb-drug interactions in combination therapy.

Glycoprotein 130 cytokine signal as a therapeutic target against cardiovascular diseases

Postnatal cardiomyocytes have only limited capacity of proliferation. Therefore, the myocardium is intrinsically equipped with cardioprotective machineries and protects itself from pathological stresses. One of the most important cardioprotective systems is the signal network of autocrine/paracrine factors, including neurohumoral factors, growth factors, and cytokines. In this review, we focus on the roles of interleukin-6 (IL-6) family cytokines, also known as glycoprotein 130 (gp130) cytokines, in cardioprotection. These cytokines make a complex with their specific cytokine receptor α-subunits. The cytokine-receptor α-subunit complex binds to gp130, a common receptor of the IL-6 family, followed by the activation of JAK/STAT, ERK, and PI3 kinase/Akt pathways. In cardiomyocytes, signals through gp130 promote cell survival and angiogenesis through the JAK/STAT pathway. Activation of gp130 in cardiac stem cells induces their endothelial transdifferentiation, leading to neovascularization. Recently, accumulating evidence has revealed that altered JAK/STAT activity is associated with heart failure, suggesting that the JAK/STAT pathway is a therapeutic target against cardiovascular diseases. Interestingly, activation of the JAK/STAT pathway with interleukin-11 (IL-11) exhibits preconditioning effects in ischemia/reperfusion model. Moreover, IL-11 treatment after coronary ligation prevents cardiac remodeling through the JAK/STAT pathway. Since IL-11 is used for patients with thrombocytopenia, we propose that IL-11 is a candidate cytokine clinically available for cardioprotection therapy.

[Genetic analysis for nicotine dependence]

Smoking cessation is extremely important to prevent the development of the serious diseases, such as COPD and cancers. Absorbed nicotine through smoking into the body is mainly metabolized by cytochrome P450 (CYP) 2A6. On the other, the nicotine acts in the brain through neuronal nicotinic acetylcholine receptors (nAChRs), which regulate the addictive properties of nicotine. Many associated studies have implicated genetic backgrounds influence smoking behavior and nicotine dependence. In these concepts, we here discuss the genes related to nicotine dependence from the pharmacokinetic and pharmacodynamic aspects of nicotine. Referring to the genome association studies, better understanding the molecular mechanisms of nicotine dependence would help to design targeted, more effective therapies for the tobacco-related diseases and smoking cessation program.

The relationship between clinical pharmacokinetics of aripiprazole and CYP2D6 genetic polymorphism: effects of CYP enzyme inhibition by coadministration of paroxetine or fluvoxamine

Purpose

To investigate the effects of coadministration of paroxetine or fluvoxamine on the pharmacokinetics of aripiprazole in healthy adult Japanese with different CYP2D6 genotypes.

Methods

Fourteen CYP2D6 extensive metabolizer (EM) and 14 CYP2D6 intermediate metabolizer (IM) subjects were coadministered a single oral dose of aripiprazole 3 mg after steady-state plasma concentrations of the SSRIs paroxetine (20 mg/day) or fluvoxamine (100 mg/day) were reached by repeated oral doses for 6–7 days. The pharmacokinetics of aripiprazole with and without coadministration of SSRIs were compared according to CYP2D6 genotypes.

Results

Coadministration of paroxetine, a potent CYP2D6 inhibitor, decreased systemic clearance (CL/F) of aripiprazole by 58 and 23% in CYP2D6 EMs and IMs, respectively, demonstrating that the percentage inhibition of CYP2D6 activity by coadministration of paroxetine was apparently greater in CYP2D6 EMs than in IMs. Coadministration of fluvoxamine, a less potent CYP3A4 inhibitor, decreased the CL/F of aripiprazole by 39% in CYP2D6 EMs and 40% in IMs, indicating the same inhibitory effect on CYP enzymes, regardless of the CYP2D6 genotype. Percent contribution of CYP2D6 to total CL/F (CYP2D6 plus CYP3A4) of aripiprazole estimated as a reduced percentage of CL/F by CYP enzyme inhibition was 62% for CYP2D6 EMs and 24% for IMs in paroxetine coadministration, and 40% for CYP2D6 EMs and 18% for IMs in fluvoxamine coadministration.

Conclusions

There were marked differences in the degree of influence of paroxetine coadministration on the pharmacokinetics of aripiprazole between CYP2D6 EMs and IMs, but no apparent differences were found between two CYP2D6 genotypes in fluvoxamine coadministration. Aripiprazole can be used safely in combination with SSRIs that have a CYP enzyme-inhibitory action.

STAT3/Pim-1 signaling pathway plays a crucial role in endothelial differentiation of cardiac resident Sca-1+ cells both in vitro and in vivo

Cardiac stem cells potentially differentiate into cardiac cells, including cardiomyocytes and endothelial cells (ECs). Previously we demonstrated that STAT3 activation by IL-6 family cytokines, such as leukemia inhibitory factor (LIF), induces the endothelial differentiation of cardiac Sca-1+ cells. In this study, we addressed molecular mechanisms for EC differentiation of Sca-1+ cells. First, DNA array experiments were performed to search for the molecules induced by LIF. Among 134 genes that LIF upregulated by more than 4 fold, we focused on Pim-1 gene transcript, because Pim-1 is associated with the differentiation of some cell lineages. Real time RT-PCR analyses confirmed that LIF stimulation upregulated Pim-1 expression. Adenoviral transfection of dominant negative (dn) STAT3 inhibited LIF-mediated induction of Pim-1, while the overexpression of constitutively active STAT3 upregulated Pim-1 expression, suggesting that STAT3 activation is necessary and sufficient for Pim-1 induction. Moreover, in STAT3-deficient Sca-1+ cells, LIF failed to induce Pim-1 expression and EC differentiation. Importantly, the overexpression of dnPim-1 abrogated the induction of EC markers, indicating Pim kinase activity is indispensable for STAT3-mediated EC differentiation in vitro. Finally, Sca-1+ cells labeled with LacZ were transplanted into post-infarct myocardium and the transdifferentiation was estimated. The overexpression of wild-type STAT3 by adenovirus vector significantly promoted EC differentiation, while STAT3 gene ablation reduced the frequency of differentiating cells in post-infarct myocardium. Furthermore, transplanted Sca-1+ cells overexpressing dnPim-1 showed the reduced frequency of EC differentiation and capillary density. Collectively, Pim-1 kinase is upregulated by STAT3 activation in cardiac Sca-1+ cells and plays a pivotal role in EC differentiation both in vitro and in vivo.

A novel saccharification method of starch using microwave irradiation with addition of activated carbon

Activated carbons were investigated for their heat catalytic effects to improve saccharification of starch by autohydrolysis in water under microwave electromagnetic field, and the results were compared with graphite and carbon nanotubes. The activated carbons with low adsorptive capacity of maltose showed high saccharification rate, while those with high adsorptive capacity exhibited low saccharification. In addition, the former activated carbons decreased the saccharification temperature by 10-30°C. Maltooligosaccharides produced in the presence of the latter activated carbons were recovered by desorption with 50% aqueous ethanol. The results indicated that both adsorptive capacities of maltooligosaccharides and catalytic effects of hot spots arisen from the uneven surface structure of activated carbons might contribute to the improvement in starch saccharification.

Role of mitochondrial permeability transition in taurine deficiency-induced apoptosis

It has recently been shown that taurine deficiency leads to impaired respiratory chain function, resulting in reduced ATP generation and enhanced oxidative stress. Because cardiomyopathy develops in taurine-deficient animals, the hypothesis that mitochondrial oxidative stress may contribute to the development of cardiomyocyte dysfunction and cell death was tested. Isolated neonatal cardiomyocytes incubated in medium containing the taurine transport inhibitor, beta-alanine, lost nearly one-half of their cellular taurine content after 48 h. Accompanying the loss of taurine was a time-dependent increase in apoptosis, which was prevented by the mitochondrial permeability transition inhibitor, cyclosporin A. Two taurine-dependent factors, oxidative stress and calcium overload, serve as important regulators of the mitochondrial permeability transition. Although taurine deficiency slowed the removal of calcium from the cytosol, it had no effect on diastolic calcium content and only modestly reduced systolic calcium content, suggesting that calcium overload is not the trigger for mitochondrial permeability transition pore formation. On the other hand, the glutathione redox ratio was significantly altered in the taurine-deficient cardiomyocyte, suggesting that oxidative stress is the primary initiator of mitochondrial permeability transition and apoptosis in the taurine-deficient cardiomyocyte.

Cigarette smoke extract induces CYP2B6 through constitutive androstane receptor in hepatocytes

Smoking induces a wide range of drug-metabolizing enzymes. Among them, CYP2B6 as well as CYP1A2 is well known to be up-regulated in smokers. Although the induction of CYP1A2 is mediated by the aryl hydrocarbon receptor, the molecular mechanisms of CYP2B6 induction by smoking remain to be fully elucidated. In this study, by preparing cigarette smoke extract (CSE), we addressed the possibility that human constitutive androstane receptor (hCAR) is involved in smoking-mediated induction of CYP2B6. In HepG2 cells, CSE induced CYP1A2 but not CYP2B6, suggesting that CYP2B6 expression is differentially regulated from CYP1A2. Compared with liver in vivo, hCAR expression is dramatically reduced in cultured hepatocytes, such as HepG2. Therefore, to reconstitute hCAR signaling pathways in vitro, we generated adenovirus vector expressing hCAR. Real-time reverse transcription-polymerase chain reaction analyses revealed that the adenoviral transfection of hCAR resulted in the up-regulation of CYP2B6 mRNA, even in the absence of CSE. It is interesting to note that CSE stimulation augmented hCAR-mediated induction of CYP2B6. In contrast, the expression of CYP2B6 was not enhanced by adenovirus vector expressing β-galactosidase, a control vector, either in the presence or absence of CSE. In summary, hCAR mediated the CYP2B6 induction by CSE in Hep2G cells. These data suggest that smoking up-regulates CYP2B6 through hCAR in vivo.

Optimization of microwave-assisted extraction of carbohydrates from industrial waste of corn starch production using response surface methodology

Microwave-assisted extraction (MAE) was applied for production of carbohydrates mainly consisting of arabinoxylan from corn pericarp which is an industrial waste of corn starch production by using hot compressed water as a solvent. The solubilization rate increased with increase in heating temperature and reached 75.2% at 220 °C. The main extracted materials were carbohydrates consist of glucose, xylose and arabinose indicating solubilization of starch and hemicellulose, while residues were composed of cellulose. Four independent variables (heating temperature, come-up time, heating time and solid to liquid ratio) were optimized for maximizing the carbohydrates yield using the response surface methodology including fractional factorial design, the path of steepest ascent and central composite design. The optimized condition was as follows; heating temperature 176.5 °C, come-up time 2 min, heating time 16 min and solid to liquid ratio 1/20 (g/mL), respectively. The maximal yield attained 70.8% of carbohydrates with predominant production of xylo-oligosaccharides.

Effect of beta-alanine treatment on mitochondrial taurine level and 5-taurinomethyluridine content

BACKGROUND

The beta-amino acid, taurine, is a nutritional requirement in some species. In these species, the depletion of intracellular stores of taurine leads to the development of severe organ dysfunction. The basis underlying these defects is poorly understood, although there is some suggestion that oxidative stress may contribute to the abnormalities. Recent studies indicate that taurine is required for normal mitochondrial protein synthesis and normal electron transport chain activity; it is known that defects in these events can lead to severe mitochondrial oxidative stress. The present study examines the effect of taurine deficiency on the first step of mitochondrial protein synthesis regulation by taurine, namely, the formation of taurinomethyluridine containing tRNA.

METHODS

Isolated rat cardiomyocytes were rendered taurine deficient by incubation with medium containing the taurine transport inhibitor, beta-alanine. The time course of cellular and mitochondrial taurine depletion was measured. The primer extension method was employed to evaluate the effect of beta-alanine treatment on taurinomethyluridine content of tRNALeu. The protein levels of ND6 were also determined by Western blot analysis.

RESULTS

beta-alanine caused a time-dependent decrease in cellular taurine content, which were reduced in half after 48 hrs of incubation. The amount of taurine in the mitochondria was considerably less than that in the cytosol and was unaffected by beta-alanine treatment. Approximately 70% of the tRNALeu in the untreated cell lacked taurinomethyluridine and these levels were unchanged following beta-alanine treatment. Protein content of ND6, however, was significantly reduced after 48 hours incubation with beta-alanine.

CONCLUSIONS

The taurine levels of the cytosol and the mitochondria are not directly coupled. The beta-alanine-mediated reduction in taurine levels is too small to affect taurinomethyluridine levels. Nonetheless, it interferes with mitochondrial protein synthesis, as exemplified by a decrease in ND6 protein content. Thus, beta-alanine does not cause alterations in mitochondrial protein synthesis through the lowering of taurine levels.

Physiological roles of taurine in heart and muscle

Taurine (aminoethane sulfonic acid) is an ubiquitous compound, found in very high concentrations in heart and muscle. Although taurine is classified as an amino acid, it does not participate in peptide bond formation. Nonetheless, the amino group of taurine is involved in a number of important conjugation reactions as well as in the scavenging of hypochlorous acid. Because taurine is a fairly inert compound, it is an ideal modulator of basic processes, such as osmotic pressure, cation homeostasis, enzyme activity, receptor regulation, cell development and cell signalling. The present review discusses several physiological functions of taurine. First, the observation that taurine depletion leads to the development of a cardiomyopathy indicates a role for taurine in the maintenance of normal contractile function. Evidence is provided that this function of taurine is mediated by changes in the activity of key Ca²⁺ transporters and the modulation Ca²⁺ sensitivity of the myofibrils. Second, in some species, taurine is an established osmoregulator, however, in mammalian heart the osmoregulatory function of taurine has recently been questioned. Third, taurine functions as an indirect regulator of oxidative stress. Although this action of taurine has been widely discussed, its mechanism of action is unclear. A potential mechanism for the antioxidant activity of taurine is discussed. Fourth, taurine stabilizes membranes through direct interactions with phospholipids. However, its inhibition of the enzyme, phospholipid N-methyltransferase, alters the phosphatidylcholine and phosphatidylethanolamine content of membranes, which in turn affects the function of key proteins within the membrane. Finally, taurine serves as a modulator of protein kinases and phosphatases within the cardiomyocyte. The mechanism of this action has not been studied. Taurine is a chemically simple compound, but it has profound effects on cells. This has led to the suggestion that taurine is an essential or semi-essential nutrient for many mammals.

Cardiac and skeletal muscle abnormality in taurine transporter-knockout mice

Taurine, a sulfur-containing β-amino acid, is highly contained in heart and skeletal muscle. Taurine has a variety of biological actions, such as ion movement, calcium handling and cytoprotection in the cardiac and skeletal muscles. Meanwhile, taurine deficiency leads various pathologies, including dilated cardiomyopathy, in cat and fox. However, the essential role of taurine depletion on pathogenesis has not been fully clarified. To address the physiological role of taurine in mammalian tissues, taurine transporter-(TauT-) knockout models were recently generated. TauTKO mice exhibited loss of body weight, abnormal cardiac function and the reduced exercise capacity with tissue taurine depletion. In this chapter, we summarize pathological profile and histological feature of heart and skeletal muscle in TauTKO mice.

Effect of clarithromycin on the pharmacokinetics of pranlukast in healthy volunteers

Pranlukast is a cysteinyl leukotriene receptor antagonist that has been used to treat bronchial asthma and allergic rhinitis. In vitro data suggest that pranlukast is a substrate of CYP3A4. Thus, the effect of clarithromycin, a potent CYP3A4 inhibitor, on the pharmacokinetics of pranlukast was examined in an open-label, randomized, two-way crossover study in 16 healthy male volunteers. In treatment A, volunteers received a single, 225 mg dose of pranlukast. In treatment B, 200 mg of clarithromycin was administered twice daily for 7 days and a single, 225 mg dose of pranlukast was coadministered on day 7. Blood samples were collected up to 24 hours after treatment, and pranlukast concentrations in the plasma were measured. The geometric mean ratios [GMR] (90% confidence intervals [CIs]) for pranlukast AUC(0-infinity) and C(max) (with/without clarithromycin) were 1.06 (0.91, 1.24) and 1.17 (0.95, 1.45), respectively. In conclusion, clarithromycin and pranlukast could be coadministered without dose adjustment because clarithromycin minimally affected the pharmacokinetics of pranlukast.

Effect of basic fibroblast growth factor (FGF2) gene polymorphisms on SSRIs treatment response and side effects

Antidepressant response usually appears in 2 to 4 weeks and 30-40% of patients do not show a significant response although biochemical changes of monoaminergic system occur within hours after administration. Genetic factors could play a role in this process and genes involved in synaptic plasticity and neurogenesis are possible candidates. In fact, antidepressants and electroconvulsive therapy increase basic fibroblast growth factor (FGF2) and the rs1449683C/T polymorphism within this gene has been found to be a predictor for both an elevated mRNA and protein level of FGF2. Therefore we examined the possible association of rs1449683C/T and a panel of tagging SNPs in SSRI efficacy and side effects in 144 Japanese major depressive subjects followed for 6 weeks. We observed a significant association of rs1449683T (p=0.010) and rs308393C (p=0.029) variant carriers toward a better response to SSRI and of rs1048201 with higher frequency of drop out due to side effects (p=0.010), independently from clinical variables. Furthermore the rs308447T-rs308393C-rs1449683T haplotype was associated with higher response rate (p=0.012) while the rs1048201T-rs3747676T haplotype was significantly associated with higher dropped out rate (p=0.015). In conclusion, this is the first study investigating the association of antidepressant response and intolerance with FGF2 variants. This finding adds an important piece of information for the pathway of detecting the genetics of antidepressant response.

Role of antioxidant activity of taurine in diabetes

The unifying hypothesis of diabetes maintains that reactive oxygen species (ROS) generated in the mitochondria of glucose-treated cells promote reactions leading to the development of diabetic complications. Although the unifying hypothesis attributes the generation of oxidants solely to impaired glucose and fatty acid metabolism, diabetes is also associated with a decline in the levels of the endogenous antioxidant taurine in a number of tissues, raising the possibility that changes in taurine status might also contribute to the severity of oxidant-mediated damage. There is overwhelming evidence that taurine blocks toxicity caused by oxidative stress, but the mechanism underlying the antioxidant activity remains unclear. One established antioxidant action of taurine is the detoxification of hypochlorous acid. However, not all of the antioxidant actions of taurine are related to hypochlorous acid because they are detected in isolated cell systems lacking neutrophils. There are a few studies showing that taurine either modulates the antioxidant defenses or blocks the actions of the oxidants, but other studies oppose this interpretation. Although taurine is incapable of directly scavenging the classic ROS, such as superoxide anion, hydroxyl radical, and hydrogen peroxide, there are numerous studies suggesting that it is an effective inhibitor of ROS generation. The present review introduces a novel antioxidant hypothesis, which takes into consideration the presence of taurine-conjugated tRNAs in the mitochondria. Because tRNA conjugation is required for normal translation of mitochondrial-encoded proteins, taurine deficiency reduces the expression of these respiratory chain components. As a result, flux through the electron transport chain decreases. The dysfunctional respiratory chain accumulates electron donors, which divert electrons from the respiratory chain to oxygen, forming superoxide anion in the process. Restoration of taurine levels increases the levels of conjugated tRNA, restores respiratory chain activity, and increases the synthesis of ATP at the expense of superoxide anion production. The importance of this and other actions of taurine in diabetes is discussed.

Signals through glycoprotein 130 regulate the endothelial differentiation of cardiac stem cells

OBJECTIVE

Cardiac Sca-1+ cells were originally identified as multipotent stem cells. To address the regulation of their differentiation, we investigated the effects of the proinflammatory cytokines on their endothelial differentiation.

METHODS AND RESULTS

We examined the effects of the proinflammatory cytokines including tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, IL-6, IL-11, and cardiotrophin-1 (CT-1) on the cardiac Sca-1+ cell differentiation. IL-11 and CT-1, whose receptor systems use glycoprotein 130 (gp130), induced endothelial-specific genes in Sca-1+ cells, but not TNF-alpha, IL-1beta, or IL-6, analyzed by RT-PCR and by immunocytochemistry. Immnunoblot analyses showed that IL-11 and CT-1 activated signal transducer and activator of transcription 3 (STAT3), a downstream target of gp130, but not other cytokines. Though IL-6 receptor is not endogenously expressed in Sca-1+ cells, IL-6 exhibited the activity to induce the endothelial markers in the presence of soluble IL-6 receptor, an agonistic receptor, associated with STAT3 phosphorylation. Moreover, the inhibition of STAT3, by its dominant-negative form or siRNA, suppressed the induction of endothelial specific genes by IL-11 and CT-1. Finally, LIF and IL-11 transcripts were upregulated in postinfarct myocardium, accompanied by the induction of Sca-1+/VE-cadherin+ cells.

CONCLUSIONS

Gp130/STAT3 pathway plays critical roles in the regulation of endothelial differentiation of cardiac Sca-1+ cells.

[5-HT1A gene polymorphisms contributed to antidepressant response in major depression]

Variability in antidepressant response is due to genetic and environmental factors. Among genetic factors, the ones controlling for availability of the drug at the target site are interesting candidates. Rs6295C/G SNP in the 5-HT1A gene (HTR1A) has been found to affect the expression and function of HTR1A. In fact rs6295C/G is in strong linkage disequilibrium with other polymorphisms of HTR1A suggesting that those functional effects could be associated with polymorphisms other than or together with the synonymous rs6295C/G. In the present study we examined the possible association of a panel of markers in strong linkage disequilibrium of HTR1A with SSRI/SNRI response in 137 Japanese major depression subjects followed for 6 weeks. We observed a significant association of better response to antidepressant in rs10042486C/C (P < 0.0001), rs6295G/G (P < 0.0001) and rs1364043T/T (P = 0.018) genotype carriers, independently from clinical variables. Furthermore minor allele homozygous carriers in all these 3 SNPs were associated with treatment response by various assessments such as HAM-D score change over time (P = 0.001), week 2 (P < 0.0001), 4 (P = 0.007), and 6 (P = 0.048) as well as response rate (P = 0.0005) and remission rate (P = 0.004). We also pointed out the genotyping mis-definition of rs6295C/G in the previous four papers.