A GO intervention program for enhancing elementary school children's cognitive functions and control abilities of emotion and behavior: study protocol for a randomized controlled trial.

BACKGROUND: Executive function is critical for children's healthy development. We propose an intervention program to enhance children's executive function using the game, GO. Many neuroimaging studies have revealed that playing GO is related to executive function. In addition, previous studies also revealed that executive function can be enhanced by training. We will perform a randomized controlled trial to investigate the effectiveness of a GO intervention group and a control group without intervention. METHODS/DESIGN: 35 elementary school children aged 8 to 10 were recruited from Edogawa elementary school in Tokyo, Japan. They will be randomized into two groups; either the 5-week GO intervention group or no-intervention control group. We will ask the participants of the intervention group to join the GO course which will be held once every week for five weeks (total: six times). In the GO course, the children will be taught GO by the GO masters of the Nihon Ki-in and enjoy it for an hour. Besides the course, the participants will perform GO problems about twenty minutes a day, three times a week during the intervention period. We will use the Stroop task, the digit span, the Raven's colored progressive matrices, the Span-board task, and the Behavioral inhibition/behavioral activation scale for the outcome measures. Outcomes will be measured at a baseline (Assessment 1) and 5 weeks after the intervention program started (Assessment 2). The intervention group will be compared with the control group using one-way analyses of covariance with the difference between Assessment 1 and Assessment 2 measures as dependent variables and pretest scores as covariates. DISCUSSION: To our knowledge, this study will be the first RCT to investigate the efficacy of a GO intervention program for elementary school children. If this intervention is effective, we will be able to take the next steps in making an educational program to enhance children's executive function and other cognitive abilities using GO. In addition, we further will investigate the transfer effects of the GO intervention program through executive function. We also will investigate neuroplasticity with the GO intervention using neuroimaging.

Pharmacokinetics of cycloalliin, an organosulfur compound found in garlic and onion, in rats.

Cycloalliin, an organosulfur compound found in garlic and onion, has been reported to exert several biological activities and also to remain stable during storage and processing. In this study, we investigated the pharmacokinetics of cycloalliin in rats after intravenous or oral administration. Cycloalliin and its metabolite, (3R,5S)-5-methyl-1,4-thiazane-3-carboxylic acid, in plasma, urine, feces, and organs was determined by a validated liquid chromatography-mass spectrometry method. When administered intravenously at 50 mg/kg, cycloalliin was rapidly eliminated from blood and excreted into urine, and its total recovery in urine was 97.8% +/- 1.3% in 48 h. After oral administration, cycloalliin appeared rapidly in plasma, with a tmax of 0.47 +/- 0.03 h at 25 mg/kg and 0.67 +/- 0.14 h at 50 mg/kg. Orally administered cycloalliin was distributed in heart, lung, liver, spleen, and especially kidney. The Cmax and AUC0-inf values of cycloalliin at 50 mg/kg were approximately 5 times those at 25 mg/kg. When administered orally at 50 mg/kg, cycloalliin was excreted into urine (17.6% +/- 4.2%) but not feces. However, the total fecal excretion of (3R,5S)-5-methyl-1,4-thiazane-3-carboxylic acid was 67.3% +/- 5.9% (value corrected for cycloalliin equivalents). In addition, no (3R,5S)-5-methyl-1,4-thiazane-3-carboxylic acid was detected in plasma (<0.1 microg/mL), and negligible amounts (1.0% +/- 0.3%) were excreted into urine. In in vitro experiments, cycloalliin was reduced to (3R,5S)-5-methyl-1,4-thiazane-3-carboxylic acid during anaerobic incubation with cecal contents of rats. These data indicated that the low bioavailability (3.73% and 9.65% at 25 and 50 mg/kg, respectively) of cycloalliin was due mainly to reduction to (3R,5S)-5-methyl-1,4-thiazane-3-carboxylic acid by the intestinal flora and also poor absorption in the upper gastrointestinal tract. These findings are helpful for understanding the biological effects of cycloalliin.

Oral administration of a zinc complex improves type 2 diabetes and metabolic syndromes.

Previously, we reported that intraperitoneal injections of the Zn(II) complex (Zn(alx)(2)) with allixin, which is isolated from dry garlic, with a Zn(O(4)) coordination environment, exhibited high anti-diabetic effects in obesity-linked type 2 diabetic KKA(y) mice. However, this complex exhibited low activity when administered orally. To improve the effect of Zn(alx)(2), we prepared a novel Zn(II) complex with the allixin-derivative bis(1,6-dimethyl-3-hydroxy-5-methoxy-2-pentyl-1,4-dihydropyridine-4- thionato)Zn(II), abbreviated as Zn(II)-thioallixin-N-methyl (Zn(tanm)(2)), having a Zn(S(2)O(2)) coordination environment; this complex has extremely high in vitro insulin-like activity. Because Zn was extensively absorbed from the gastrointestinal tract when Zn(tanm)(2) was orally administered, its anti-diabetic effects were examined in KKA(y) mice. Daily oral administrations of Zn(tanm)(2) for 4 weeks in KKA(y) mice significantly improved hyperglycemia, glucose intolerance, insulin resistance, hyperleptinemia, obesity, and hypertension. Interestingly, Zn(tanm)(2) increased depressed plasma adiponectin levels in the mice. Here, we propose that Zn(tanm)(2) will be an orally active therapeutic for obesity-linked type 2 diabetes and metabolic syndromes.

Improvement of diabetes, obesity and hypertension in type 2 diabetic KKAy mice by bis(allixinato)oxovanadium(IV) complex.

Previously, we found that bis(allixinato)oxovanadium(IV) (VO(alx)(2)) exhibits a potent hypoglycemic activity in type 1-like diabetic mice. Since the enhancement of insulin sensitivity is involved in one of the mechanisms by which vanadium exerts its anti-diabetic effects, VO(alx)(2) was further tested in type 2 diabetes with low insulin sensitivity. The effect of oral administration of VO(alx)(2) was examined in obesity-linked type 2 diabetic KKA(y) mice. Treatment of VO(alx)(2) for 4 weeks normalized hyperglycemia, glucose intolerance, hyperinsulinemia, hypercholesterolemia and hypertension in KKA(y) mice; however, it had no effect on hypoadiponectinemia. VO(alx)(2) also improved hyperleptinemia, following attenuation of obesity in KKA(y) mice. This is the first example in which a vanadium compound improved leptin resistance in type 2 diabetes by oral administration. On the basis of these results, VO(alx)(2) is proposed to enhance not only insulin sensitivity but also leptin sensitivity, which in turn improves diabetes, obesity and hypertension in an obesity-linked type 2 diabetic animal.

Bis(allixinato)oxovanadium(IV) complex is a potent antidiabetic agent: studies on structure-activity relationship for a series of hydroxypyrone-vanadium complexes.

There is an urgent medical need for orally effective drugs to replace insulin injections for the treatment of diabetes mellitus. Vanadium complexes with insulin-mimetic activities have recently been proposed as candidates as new antidiabetic drugs. Following in vitro and in vivo studies on a group of bis(3-hydroxy-4-pyronato)oxovanadium(IV) (1) complexes with VO(O4) coordination mode, bis(allixinato)oxovanadium(IV) (3) which contains allixin, a garlic component, was found to be the most potent antidiabetic agent among them. Complex 3 with a high in vitro insulin-mimetic activity in terms of both free fatty acid (FFA)-release inhibitory and glucose-uptake enhancing activities in isolated rat adipocytes exhibited a high hypoglycemic effect in type 1 diabetic model mice by both intraperitoneal injections and oral administrations. Complex 3 is thus proposed to be one of the most effective candidates for antidiabetic therapy.

Determination of seven organosulfur compounds in garlic by high-performance liquid chromatography.

The properties of garlic (Allium sativum L.) are attributed to organosulfur compounds. Although these compounds change during cultivation and storage, there is no report of their simultaneous analysis. Here, a newly developed analytical method with a rapid and simple sample preparation to determine four sulfoxides and three gamma-glutamyl peptides in garlic is reported. All garlic samples were simply extracted with 90% methanol solution containing 0.01 N hydrochloric acid and prepared for analysis. Alliin, isoalliin, methiin, cycloalliin, and gamma-l-glutamyl-S-methyl-l-cysteine were determined by normal-phase HPLC using an aminopropyl-bonded column. gamma-l-Glutamyl-S-(2-propenyl)-l-cysteine and gamma-l-glutamyl-S-(trans-1-propenyl)-l-cysteine were separated on an octadecylsilane column. The overall recoveries were 97.1-102.3%, and the relative standard deviation values of intra- and interday precision were lower than 2.6 and 4.6%, respectively. This newly developed method offers some advantages over the currently accepted techniques including specificity, speed, and ease of use and would be useful for chemical and biological studies of garlic and its preparations.

Tetrahydro-beta-carboline derivatives in aged garlic extract show antioxidant properties.

This study used the hydroden peroxide scavenging assay to investigate antioxidant chemical constituents derived and separated from aged garlic extract, a unique garlic extract produced by soaking sliced garlic in an aqueous ethanol solution for >10 mo. Four types of 1, 2, 3, 4-tetrahydro-beta-carboline derivatives (THbetaCs); 1-methyl-1, 2, 3, 4-tetrahydro-beta-carboline-3-carboxylic acid, and 1-methyl-1, 2, 3, 4-tetrahydro-beta-carboline-1, 3-dicarboxylic acid (MTCdiC), from both diastereoisomers, were isolated and identified by use of liquid chromatography-mass spectrometry. All these compounds indicate strong hydrogen peroxide scavenging activities and inhibit 2, 2'-azobis(2-amidinopropane) hydrochloride-induced lipid peroxidation. Particularly, (1S, 3S)-MTCdiC had the most potent hydrogen peroxide scavenging activity, more than ascorbic acid. The (1R, 3S)- and (1S, 3S)-MTCdiC at 50-100 micromol/L and 10-100 micromol/L inhibited LPS-induced nitrite production. Interestingly, THbetaCs were not detected in raw garlic and other processed garlic preparations, but they were generated and increased during the natural aging garlic extraction process. These data suggest that THbetaCs, which are formed during the natural aging process, are potent antioxidants in aged garlic extract and thus may be useful for the prevention of diseases associated with oxidative damage.

Hydroponic cultivation offers a practical means of producing selenium-enriched garlic.

Garlic enriched by selenium (Se) could be an excellent source of dietary Se for cancer chemoprevention. The production of high-Se garlic requires Se-fertilized soil, but such soil may pollute the environment. Hydroponics is a closed system that allows good control over Se fertilization without environmental consequences. We examined the effect of hydroponic cultivation on Se uptake and assimilation in garlic seedlings. Garlic bulbs were grown in the nutrient solution without Se for first 2 wk, and with potassium selenate for an additional week. Sulfate in an ordinary hydroponic solution inhibited the absorption and assimilation of selenate, but when a sulfate-free nutrient was used for Se addition, the garlic seedlings accumulated >1 mg Se, dry weight. Through HPLC inductively coupled plasma MS (HPLC-ICP-MS) analysis, Se-methlyselenocysteine (MeSeCys), gamma-glutamyl-Se-methlyselenocysteine (gamma-GluMeSeCys), selenomethionine, and nonmetabolized selenate were identified in water extracts of the garlic seedlings. The results demonstrate that hydroponic enrichment of Se in garlic seedlings could be a practical means of producing organic Se compounds for nutritional supplements.

A new insulin-mimetic bis(allixinato)zinc(II) complex: structure-activity relationship of zinc(II) complexes.

During the investigation of the development of insulin-mimetic zinc(II) complexes with a blood glucose-lowering effect in experimental diabetic animals, we found a potent bis(maltolato)zinc(II) complex, Zn(ma)(2), exhibiting significant insulin-mimetic effects in a type 2 diabetic animal model. By using this Zn(ma)(2) as the leading compound, we examined the in vitro and in vivo structure-activity relationships of Zn(ma)(2) and its related complexes. The in vitro insulin-mimetic activity of these complexes was determined by the inhibition of free fatty acid release and the enhancement of glucose uptake in isolated rat adipocytes treated with epinephrine. A new Zn(II) complex with allixin isolated from garlic, Zn(alx)(2), exhibited the highest insulin-mimetic activity among the complexes analyzed. The insulin-mimetic activity of the Zn(II) complexes examined strongly correlated (correlation coefficient=0.96) with the partition coefficient (log P) of the ligand, indicating that the activity of Zn(ma)(2)-related complexes depends on the lipophilicity of the ligand. The blood glucose-lowering effects of Zn(alx)(2) and Zn(ma)(2) were then compared, and both complexes were found to normalize hyperglycemia in KK- A(y) mice after a 14-day course of daily intraperitoneal injections. However, Zn(alx)(2) improved glucose tolerance in KK- A(y) mice much more than did Zn(ma)(2), indicating that Zn(alx)(2) possesses greater in vivo anti-diabetic activity than Zn(ma)(2). In addition, Zn(alx)(2) improved leptin resistance and suppressed the progress of obesity in type 2 diabetic KK- A(y) mice. On the basis of these observations, we conclude that the Zn(alx)(2) complex is a novel potent candidate for the treatment of type 2 diabetes mellitus.

Identification of six phenylpropanoids from garlic skin as major antioxidants.

The extract of garlic skins (peels) showed strong antioxidant activity, and some responsible constituents were isolated and identified. Garlic (Allium sativum L.) has been used as an herbal medicine, but there is no report on the health benefits of the skin or peel. In this study, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of garlic skin extract was evaluated. Using chromatographic techniques, the active constituents were isolated and subsequently identified. Analyses by high-performance liquid chromatography coupled with a photodiode array detector (HPLC-PDA) suggested that these compounds were phenylpropanoids, which had a characteristic absorbance at 300-320 nm. Liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance analyses allowed the chemical structures of the isolated constituents to be postulated. The proposed compounds were subsequently synthesized and compared with the constituents in the extract using HPLC-PDA and LC-MS. N-trans-Coumaroyloctopamine, N-trans-feruloyloctopamine, guaiacylglycerol-beta-ferulic acid ether, and guaiacylglycerol-beta-caffeic acid ether were identified as were trans-coumaric acid and trans-ferulic acid. Also, the antioxidant activities of these compounds were determined.

A novel antibacterial 8-chloroquinolone with a distorted orientation of the N1-(5-amino-2,4-difluorophenyl) group.

Fluoroquinolones represent a major class of antibacterial agents with great therapeutic potential. In this study, we designed m-aminophenyl groups as novel N-1 substituents of naphthyridones and quinolones. Among newly synthesized compounds, 7-(3-aminoazetidin-1-yl)-1-(5-amino-2,4-difluorophenyl)-8-chloro-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (4) has extremely potent antibacterial activities against Gram (+) as well as Gram (-) bacteria. This compound is significantly more potent than trovafloxacin against clinical isolates: 30 times against Streptococcus pneumoniae and 128 times against methicillin resistant Staphylococcus aureus. The structure-activity relationship (SAR) study revealed that a limited combination of 1-(5-amino-2,4-difluorophenyl) group, 7-(azetidin-1-yl) group, and 8-Cl atom (or Br atom or Me group) gave potent antibacterial activity. An X-ray crystallographic study of a 7-(3-ethylaminoazetidin-1-yl)-8-chloro derivative demonstrated that the N-1 aromatic group was remarkably distorted out of the core quinolone plane by steric repulsion between the C-8 Cl atom and the N-1 substituent. Furthermore, a molecular modeling study of 4 and its analogues demonstrated that a highly distorted orientation was induced by a steric hindrance of the C-8 substituent, such as Cl, Br, or a methyl group. Thus, their highly strained conformation should be a key factor for the potent antibacterial activity.

Pharmacokinetic study of allixin, a phytoalexin produced by garlic.

The pharmacokinetic behavior of allixin (3-hydroxy-5-methoxy-6-methyl-2-penthyl-4H-pyran-4-one) was investigated in an experimental animal, mice. Allixin was administered using an inclusion compound because the solubility of allixin in aqueous solution is very low. The allixin content in serum and in the organs of administered animals was analyzed by liquid chromatography (LC)-MS. Most of the administered allixin disappeared within 2 h, and the bioavailability of allixin was estimated to be 31% by obtained area under the blood concentration-time curve (AUC). The metabolites of allixin were studied using the metabolic enzyme fraction of liver and liver homogenate. Several new peaks corresponding to allixin metabolites were observed in the HPLC chromatoprofile. The chemical structure of the metabolites was investigated using LC-MS and NMR. Three of them were identified as allixin metabolites having a hydroxylated pentyl group.

Antioxidant effects of tetrahydro-beta-carboline derivatives identified in aged garlic extract.

1,2,3,4-Tetrahydro-beta-carboline derivatives (THbetaCs) are formed through Pictet-Spengler chemical condensation between tryptophan and aldehydes during food production, storage and processing. In the present study, in order to identify the antioxidants in aged garlic extract (AGE), we fractionated it and identified four THbetaCs; 1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acids (MTCC) and 1-methyl-1,2,3,4-tetrahydro-beta-carboline-1,3-dicarboxylic acid (MTCdiC) in both diastereoisomers using liquid chromatography mass spectrometry (LC-MS). Interestingly, these compounds were not detected in raw garlic, but the contents increased during the natural aging process of garlic. In in vitro assay systems, all of these compounds have shown strong hydrogen peroxide scavenging activities. (1S, 3S)-MTCdiC was found to be stronger than the common antioxidant, ascorbic acid. MTCC and MTCdiC inhibited AAPH-induced lipid peroxidation. Both MTCdiCs also inhibited LPS-induced nitrite production from murine macrophages at 10-100 microM. Our data suggest that these compounds are potent antioxidants in AGE, and thus may be useful for prevention of disorders associated with oxidative stress.