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1.
Nutrients ; 15(17)2023 Aug 24.
Article in English | MEDLINE | ID: mdl-37686734

ABSTRACT

Hesperetin, a citrus flavonoid, exerts vasodilation and is expected to improve endothelial function and alleviate cold sensation by activating nervous system thermal transduction pathways. In this randomized, double-blind, crossover, and placebo-controlled study, the purpose was to assess the effect of an orally administered highly bioavailable soluble inclusion complex of hesperetine-7-O-glucoside with ß-cyclodextrin (HEPT7G/ßCD; SunActive® HES/HCD) on cold sensation response during localized cold-stimulated stress in healthy humans. A significant (p ≤ 0.05) dose-dependent increase in skin cutaneous blood flow following relatively small doses of HEPT7G/ßCD inclusion complex ingestion was confirmed, which led to a relatively effective recovery of peripheral skin temperature. The time delay of an increase in blood flow during rewarming varied significantly between low- and high-dose HEPT7G/ßCD inclusion complex consumption (e.g., 150 mg and 300 mg contain 19.5 mg and 39 mg of HEPT7G, respectively). In conclusion, the substantial alteration in peripheral skin blood flow observed during local cooling stress compared to placebo suggested that deconjugated hesperetin metabolites may have a distinct capacity for thermoregulatory control of human skin blood flow to maintain a constant body temperature during cold stress exposure via cutaneous vasodilation and vasoconstriction systems.


Subject(s)
Glucosides , Vasodilator Agents , Humans , Glucosides/pharmacology , Healthy Volunteers , Sensation
2.
Biosci Biotechnol Biochem ; 87(7): 771-776, 2023 Jun 23.
Article in English | MEDLINE | ID: mdl-37133406

ABSTRACT

Diosmin (DSN) is found mainly in citrus fruits, and has potent antioxidant effects. This study aimed to evaluate pharmacokinetics of diosmetin-7-glucoside-γ-cyclodextrin (DIOSG-CD) inclusion complex. The area under the curve values from AUC0-24 of DIOSG-CD, prepared by reacting DSN and naringinase with γ-CD, were approximately 800-fold higher than those of DSN following their administration in Sprague-Dawley rats.


Subject(s)
Diosmin , gamma-Cyclodextrins , Rats , Animals , Rats, Sprague-Dawley , Diosmin/pharmacokinetics , Biological Availability
3.
J Clin Biochem Nutr ; 72(2): 189-197, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36936875

ABSTRACT

Partially hydrolyzed guar gum dietary fiber is well recognized for a number of health benefits. In the present study, we aim to investigate the effects of partially hydrolyzed guar gum on constipation, intestinal microbiota as well as mental health in healthy subjects. In the randomized, parallel, double-blind, and placebo-controlled study the enrolled healthy men and women volunteers took either 3 g/day (T3) or 5 g/day (T5) of dietary fiber intakes for eight consecutive weeks compared to placebo (T0). The fecal characteristics, fecal microbiota, defecation characteristics, and quality of life (QOL) questionnaire were investigated. The results revealed a significant suppression in fecal potent harmful mucolytic bacteria in the T3 and T5 groups compared to the T0 group. The defecation frequency, excretory feeling, and scores of sleep and motivation questionnaire were also improved in the dietary fiber intake groups, showing a significant difference in the T5 group compared to the T0 group. In summary, the consumption of partially hydrolyzed guar gum dietary fiber is found effective in suppressing the potent harmful mucolytic bacteria that could be associated with the improvement of constipation-related symptoms including mental health in terms of sleep and motivation among the healthy subjects.

4.
Contemp Clin Trials Commun ; 32: 101084, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36817736

ABSTRACT

Iron is specifically important to athletes, and attention has grown to the association between sports performance and iron regulation in the daily diets of athletes. The study presents new insights into stress, mood states, fatigue, and sweating behavior among the non-anemic athletes with sweating exercise habits who consumed a routine low dose (3.6 mg/day) of iron supplementation. In this double-blind, randomized, placebo-controlled, parallel-group study, both non-anemic male (N = 51) and female (N = 42) athletes were supplemented either with a known highly bioavailable iron formulation (SunActive® Fe) or placebo during the follow-up training exercise period over four weeks at their respective designated clinical sites. The effect of oral iron consumption was examined on fatigue, stress profiles, as well as the quality of life using the profile of mood state (POMS) test or a visual analog scale (VAS) questionnaire, followed by an exercise and well-being related fatigue-sweat. Also, their monotonic association with stress biomarkers (salivary α-amylase, salivary cortisol, and salivary immunoglobulin A) were determined using spearman's rank correlation coefficient test. Repeated measure multivariate analysis of variance (group by time) revealed that the total mood disturbance (TMD) score was significantly lower (P = 0.016; F = 6.26) between placebo and iron supplementation groups over the four weeks study period among female athletes. Also, a significant reduction in tired feeling/exhaustion after the exercise (P = 0.05; F = 4.07) between the placebo and iron intake groups was noticed. A significant within-group reduction (P ≤ 0.05) was noticed in the degree of sweat among both male and female athletes after 2 and 4 weeks of iron supplementation, while athletes of the placebo intake group experienced a non-significant within-group reduction in the degree of sweat. Overall, the result indicates routine use of low dose (3.6 mg/day) iron supplementation is beneficial for non-anemic endurance athletes to improve stress, mood states, subjective fatigue, and sweating conditions.

5.
Int J Toxicol ; 42(1): 50-62, 2023.
Article in English | MEDLINE | ID: mdl-36280476

ABSTRACT

Hesperetin glucosides such as hesperidin and hesperetin-7-glucoside are abundantly present in citrus fruits and have various pharmacological properties. However, the potential toxicity of hesperetin glucosides remains unclear. An initial assessment of the safety of hesperetin-7-glucoside-ß-cyclodextrin inclusion complex (HPTGCD) as a functional food ingredient was undertaken to assess toxicity and mutagenic potential. A bacterial reverse mutation assay (Ames test) using Salmonella typhimurium (strains TA98, TA1535, TA100, and TA1537) and Escherichia coli (strain WP2 uvrA) with HPTGCD (up to 5000 µg/plate) in the absence and presence of metabolic activation was negative. In a single oral (gavage) toxicity study in male and female rats, HPTGCD at dose up to 2000 mg/kg did not produce mortality nor clinical signs of toxicity or change in body weight. In a subchronic oral (dietary admix) toxicity study in rats receiving 0, 1.5, 3, and 5% HPTGCD for 13 weeks, no adverse effects were noted and the no-observed-adverse-effect level (NOAEL) was 5% in the diet (equivalent to 3267.7 mg/kg/day for males and to 3652.4 mg/kg/day for females). These results provide initial evidence of the safety of HPTGCD.


Subject(s)
Hesperidin , Mutagens , Rats , Male , Female , Animals , Mutagenicity Tests/methods , Hesperidin/toxicity , Mutation
6.
Nutrients ; 14(20)2022 Oct 11.
Article in English | MEDLINE | ID: mdl-36296915

ABSTRACT

The purpose of the present study was to elucidate the rate of water absorption of an oral rehydration solution containing partially hydrolyzed guar gum (PHGG) in the small intestine, which is the main site of water absorption when water is drunk. Seven-week-old male SD rats were employed. We prepared four types of an aqueous solution, i.e., containing mineral and sugar, containing PHGG, containing mineral and sugar and PHGG, or containing no additives. After 24 h of food and 4 h of water deprivation, the aqueous solutions were infused into the stomach of conscious rats on their hands using a syringe with a stomach sonde. We sampled the stomach and the small intestine with contents 8 min after the infusions. Causal effects were calculated using a Bayesian network. PHGG increased the residual amount of water in the gastro-intestine, which depends negatively on the absorption of water in the small intestine/the flow rate to the small intestine. The absorption of water in the small intestine depended positively on the flow rate to the small intestine, which depended negatively on the free water in the solutions. PHGG decreased water absorption in the small intestine by decreasing the free water in the aqueous solutions.


Subject(s)
Rehydration Solutions , Water , Male , Rats , Animals , Bayes Theorem , Rats, Sprague-Dawley , Galactans , Plant Gums , Mannans , Glucose , Minerals , Dietary Fiber
7.
Molecules ; 27(17)2022 Aug 24.
Article in English | MEDLINE | ID: mdl-36080157

ABSTRACT

Flavonoids are biologically active natural products of great interest for their potential applications in functional foods and pharmaceuticals. A hesperetin-7-O-glucoside inclusion complex with ß-cyclodextrin (HEPT7G/ßCD; SunActive® HCD) was formulated via the controlled enzymatic hydrolysis of hesperidin with naringinase enzyme. The conversion rate was nearly 98%, estimated using high-performance liquid chromatography analysis. The objective of this study was to investigate the stability, solubility, and spectroscopic features of the HEPT7G/ßCD inclusion complex using Fourier-transform infrared (FTIR), Raman, ultraviolet-visible absorption (UV-vis), 1H- and 13C- nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), liquid chromatography/mass spectroscopy (LC-MS), scanning electron microscopy (SEM), and powdered X-ray diffraction (PXRD) spectroscopic techniques including zeta potential, Job's plot, and phase solubility measurements. The effects of complexation on the profiles of supramolecular interactions in analytic features, especially the chemical shifts of ß-CD protons in the presence of the HEPT7G moiety, were evaluated. The stoichiometric ratio, stability, and solubility constants (binding affinity) describe the extent of complexation of a soluble complex in 1:1 stoichiometry that exhibits a greater affinity and fits better into the ß-CD inner cavity. The NMR spectroscopy results identified two different configurations of the HEPT7G moiety and revealed that the HEPT7G/ßCD inclusion complex has both -2S and -2R stereoisomers of hesperetin-7-O-glucoside possibly in the -2S/-2R epimeric ratio of 1/1.43 (i.e., -2S: 41.1% and -2R: 58.9%). The study indicated that encapsulation of the HEPT7G moiety in ß-CD is complete inclusion, wherein both ends of HEPT7G are included in the ß-CD inner hydrophobic cavity. The results showed that the water solubility and thermal stability of HEPT7G were apparently increased in the inclusion complex with ß-CD. This could potentially lead to increased bioavailability of HEPT7G and enhanced health benefits of this flavonoid.


Subject(s)
Hesperidin , beta-Cyclodextrins , Calorimetry, Differential Scanning , Flavonoids/chemistry , Glucosides , Protons , Solubility , Spectroscopy, Fourier Transform Infrared/methods , X-Ray Diffraction , beta-Cyclodextrins/chemistry
8.
J Toxicol Sci ; 47(6): 221-235, 2022.
Article in English | MEDLINE | ID: mdl-35650139

ABSTRACT

Flavonoids such as quercetin and its glucosides, especially isoquercitrin are well known as anti-inflammatory, anti-allergic, and anti-carcinogenic, etc. The safety of isoquercitrin formulations needs to be established prior to their use in functional food applications. The mutagenicity and genotoxicity of the IQC-γCD inclusion complex were assessed with three standard assays of the bacterial reverse mutation assay (Ames test) and using a combined in-vivo micronucleus and comet assay under the Organisation for Economic Co-operation and Development (OECD) guidelines. In combined rat bone marrow micronucleus and rat liver comet assay performed in male Sprague Dawley (SD) rats, the various doses of IQC-γCD inclusion complex (max. 2000 mg/kg bw) and positive controls ethyl methanesulfonate (EMS) and mitomycin C (MMC), respectively, and negative control (vehicle) were administrated. The results of the Salmonella typhimurium mutagenicity assay (strains TA100, TA1535, WP2uvrA, TA98, and TA1537) after exposure to the IQC-γCD inclusion complex with the absence and presence of the metabolic activation system (S9 fraction from rat liver) revealed a weakly positive response but with no biologically relevant mutagenicity at the conditions examined according to recommended regulatory guidelines. The combined micronucleus and comet assay results reveal that the IQC-γCD inclusion complex did not induce in-vivo genotoxic potential or indication of any oxidative DNA damage in rat liver tissues. Altogether, considering the results of the study, it is unlikely that the consumption of IQC-γCD inclusion complex as food or supplement would present any concern for humans regarding the mutagenicity and genotoxicity.


Subject(s)
Mutagens , gamma-Cyclodextrins , Animals , Comet Assay , DNA Damage , Male , Micronucleus Tests/methods , Mutagenicity Tests/methods , Mutagens/toxicity , Quercetin/analogs & derivatives , Quercetin/toxicity , Rats , Rats, Sprague-Dawley
9.
Biosci Biotechnol Biochem ; 85(10): 2195-2199, 2021 Sep 22.
Article in English | MEDLINE | ID: mdl-34347032

ABSTRACT

The pharmacokinetics of compounds comprising hesperetin-7-glucoside with ß-cyclodextrin and physically mixed hesperidin/dextrin was compared in 8 healthy adult male subjects in a nonrandomized, double-blind, cross-over, controlled study. For 0-24 h, the area under the curve of the total plasma hesperetin concentration after hesperetin-7-glucoside with ß-cyclodextrin consumption was >100-fold higher than that after hesperidin/dextrin consumption.


Subject(s)
Hesperidin/analogs & derivatives , Adult , Biological Availability , Humans
10.
Molecules ; 26(12)2021 Jun 17.
Article in English | MEDLINE | ID: mdl-34204433

ABSTRACT

Catechins are a part of the chemical family of flavonoids, a naturally occurring antioxidant, and a secondary metabolite in certain plants. Green tea catechins are well recognized for their essential anti-inflammatory, photo-protective, antioxidant, and chemo-preventive functions. Ultraviolet radiation is a principal cause of damage to the skin. Studies observed that regular intake of green tea catechins increased the minimal dose of radiation required to induce erythema. The objectives of this systematic review and meta-analysis are to determine the effectiveness of green tea catechins in cutaneous erythema and elucidate whether green tea catechin consumption protects against erythema (sunburn) inflammation. A comprehensive literature search was conducted to identify the relevant studies. Two researchers carried out independent screening, data extraction, and quality assessment according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). The pooled effect of green tea catechins on protection against erythema was assessed using approaches fixed-effects or random-effects model to quantify the effectiveness of green tea catechins in the erythema dose-response. Studies not be included in meta-analyses were summarized narratively. Six randomized controlled studies of enrolled studies regularly administrated green tea catechins orally for 6 to 12 weeks involving healthy volunteers comprising a total of 100 participants were included in the analysis. The results revealed green tea catechins have favorable protection against erythema inflammation even at increased minimal erythema dose (MED) of ultraviolet radiation. Meta-analysis results confirm oral supplementation of green tea catechins is highly effective at low-intensity ultraviolet radiation-induced erythema response (MED range; 1.25-1.30) compared to placebo, showing a significant pooling difference (p = 0.002) in erythema index (SMD: -0.35; 95% CI, -0.57 to -0.13; I2 = 4%, p = 0.40) in the random-effects model. The pro-inflammatory signaling pathways through oral supplementation with green tea catechins are an attractive strategy for photo-protection in healthy human subjects and could represent a complementary approach to topical sunscreens. Therefore, studies that involved green tea catechin in topical applications to human subjects were also evaluated separately, and their meta-analysis is presented as a reference. The evidence indicates that regular green tea catechin supplementation is associated with protection against UV-induced damage due to erythema inflammation.


Subject(s)
Catechin/pharmacology , Erythema/drug therapy , Tea/chemistry , Animals , Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Catechin/chemistry , Erythema/metabolism , Erythema/prevention & control , Flavonoids/metabolism , Flavonoids/pharmacology , Humans , Inflammation/drug therapy , Skin/metabolism , Sunscreening Agents/pharmacology , Tea/metabolism , Ultraviolet Rays/adverse effects
11.
Food Chem Toxicol ; 152: 112217, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33865935

ABSTRACT

Flavonoids such as quercetin and its glycoside Isoquercitrin and are abundantly present in the diet and have various pharmacological effects. However, limited data about its potential toxicity is available. In this study, we aim to evaluate the subchronic toxicity of the isoquercitrin-γ-cyclodextrin (IQC-γCD) molecular inclusion complex (SunActive® QCD/EN) in Sprague-Dawley (SD) rats. The IQC-γCD was administrated orally to 40 male and 40 female SD rats at dietary doses up to 5.0 % for 13 consecutive weeks. During the experiment periods, the general clinical signs, mortality, hematological, urinalysis values, biochemical, and histopathological parameters were examined. All animals survived until the scheduled necropsy, and no statistically significant or clinical sign of toxicologically relevant differences including pathology parameters, and histopathological endpoints were observed in any of the IQC-γCD treatment groups, compared with the control group. However, certain observations were noted in the male rats treated with the highest concentration (5.0 %), but these were not seen in female rats. A slight inhibition of weight gain was observed, probably linked to a fall in red blood cells, and hematocrit index in female rats. Statistically significant changes were noted in some clinical measures, such as plasma bilirubin level, alkaline phosphatase total bile acid without evidence of systemic clinical toxicity. The results support no observed adverse effect level (NOAEL) of IQC-γCD of 5.0 % in the diet for males (3338.55 mg/kg/day), and 3.0 % in the diet for females (2177.33 mg/kg/day) SD rats. Therefore, in this 13 weeks repeated-dose SD rat study there were no treatment-related adverse clinical or pathological findings for IQC-γCD of 5.0 % in the diet for males, and 3.0 % in the diet for females SD rats. The results of the present study support the safe use of IQC-γCD as a functional food, food additive, and natural ingredient.


Subject(s)
Quercetin/analogs & derivatives , gamma-Cyclodextrins/toxicity , Alkaline Phosphatase/blood , Animals , Body Weight/drug effects , Female , Male , No-Observed-Adverse-Effect Level , Organ Size/drug effects , Quercetin/toxicity , Rats, Sprague-Dawley , Sex Factors , Toxicity Tests, Subchronic
12.
Toxicol Rep ; 7: 386-402, 2020.
Article in English | MEDLINE | ID: mdl-32140423

ABSTRACT

As part of the United States Pharmacopeia's ongoing review of dietary supplement safety data, a new comprehensive systematic review on green tea extracts (GTE) has been completed. GTEs may contain hepatotoxic solvent residues, pesticide residues, pyrrolizidine alkaloids and elemental impurities, but no evidence of their involvement in GTE-induced liver injury was found during this review. GTE catechin profiles vary significantly with manufacturing processes. Animal and human data indicate that repeated oral administration of bolus doses of GTE during fasting significantly increases bioavailability of catechins, specifically EGCG, possibly involving saturation of first-pass elimination mechanisms. Toxicological studies show a hepatocellular pattern of liver injury. Published adverse event case reports associate hepatotoxicity with EGCG intake amounts from 140 mg to ∼1000 mg/day and substantial inter-individual variability in susceptibility, possibly due to genetic factors. Based on these findings, USP included a cautionary labeling requirement in its Powdered Decaffeinated Green Tea Extract monograph that reads as follows: "Do not take on an empty stomach. Take with food. Do not use if you have a liver problem and discontinue use and consult a healthcare practitioner if you develop symptoms of liver trouble, such as abdominal pain, dark urine, or jaundice (yellowing of the skin or eyes)."

13.
J Nutr Biochem ; 43: 1-10, 2017 05.
Article in English | MEDLINE | ID: mdl-27883924

ABSTRACT

Green tea catechins (GTCs) are known to improve fat oxidation (FOX) during fasted, rested and exercise conditions wherein epigallocatechin-3-gallate (EGCG) is thought to be the most pharmacologically active and has been studied extensively. From the available data of randomized controlled trials (RCTs) on EGCG, we carried out a systematic review and meta-analysis to elucidate whether EGCG consumption indeed increase energy expenditure (EE) and promote FOX. A systematic review of the literature was conducted using electronic databases (PubMed, Embase, Cochrane Library, CINAHL, JICST, JSTPLUS, and JMEDPLUS and others) and eight RCTs were included. RCTs were reviewed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and methodological quality was assessed. After data extraction, results were aggregated using fixed- and random-effect approaches and expressed to quantify the relationship between the dose of EGCG for respiratory quotient (RQ), EE and rate of FOX to compare the EGCG and placebo treatments. The meta-analysis results of verities of studies in terms of dose and length of duration revealed that EGCG supplementation provided significant mean difference (MD) when compared with placebo for RQ [MD: -0.02; 95% confidence intervals (95% CI), -0.04 to 0.00; I2=67%; P=.01] and EE [MD: 158.05 kJ/day; 95% CI, 4.72 to 311.38; I2=0%; P=.04] in fixed-effect approach. Changes in FOX did not reach the level of statistical significance. Meta-analyses of EGCG influence on the body mass index, waist circumference and total body fat mass (TBFM) were also examined and their impact on the promotion of FOX is reported. Effect of EGCG doses was also systematically reviewed. Finding showed that EGCG intake moderately accelerates EE and reduces RQ. The analyses revealed that the EGCG resulted in difference in RQ and EE but the effect on the other measures of energy metabolism was relatively mild. Possibly, EGCG alone has the potential to increase metabolic rate at 300 mg dose. Collectively, the outcome supports the findings that EGCG has an effect on metabolic parameters. However, the large prospective trials are needed to confirm the findings.


Subject(s)
Adipose Tissue/metabolism , Catechin/analogs & derivatives , Energy Metabolism/drug effects , Body Mass Index , Catechin/administration & dosage , Catechin/pharmacology , Dietary Supplements , Humans , Obesity/prevention & control , Oxidation-Reduction
14.
Nutrition ; 32(3): 321-31, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26695876

ABSTRACT

OBJECTIVES: The aim of this study was to investigate the effects of green tea catechins (GTC) on oxidative stress metabolites in healthy individuals while at rest and during exercise. The effects investigated included response to fat metabolism, blood lactate concentrations, and rating of perceived exertion. METHODS: In a paralleled, crossover, randomized controlled study, 16 trained male gymnastic students were randomly divided into two groups. The rest group (n = 8; GTC-NEX) received a single dose of 780 mg GTC with water but no exercise; the exercise group (n = 8; GTC-EX) received a similar dose of GTC but were instructed to exercise. This was followed by a crossover study with similar exercise regime as a placebo group (PL-EX) that received water only. Blood samples were collected at baseline and after 60 and 120 min of GTC intake. Oxidative stress blood biomarkers using the diacron reactive oxygen metabolite (d-ROMs) and biological antioxidant potential (BAP) tests; urinary 8-hydroxydeoxyguanosine (8-OHdG); 8-OHdG/creatinine; and blood lactate concentrations were analyzed. During the cycle ergometer exercise, volume of maximal oxygen uptake, volume of oxygen consumption, volume of carbon dioxide, and respiratory exchange ratio were measured from a sample of respiratory breath gas collected during low, moderate, and high intensity exercising, and the amount of fat burning and sugar consumption were calculated. Analysis of variance was used to determine statistical significance (P < 0.05) between and among the groups. RESULTS: Levels of postexercise oxidative stress metabolites BAP and d-ROMs were found significant (P < 0.0001) in the PL-EX and GTC-EX groups, and returned to pre-exercise levels after the recovery period. Levels of d-ROMs showed no significant difference from baseline upon GTC intake followed by resting and a resting recovery period in the GTC-NEX group. BAP levels were significant upon GTC intake followed by resting (P = 0.04), and after a resting recovery period (P = 0.0006) in the GTC-NEX group. Urinary 8-OHdG levels were significant (P < 0.005) for all groups after the recovery period. A significant difference was noticed between the ratios of resting BAP to d-ROMs and exercise-induced BAP to d-ROMs (P = 0.022) after 60 min of GTC intake, as well as resting 8-OHdG and exercise-induced 8-OHdG levels (P = 0.004) after the recovery period. Oxidative potentials were higher when exercise was performed at low to moderate intensity, accompanied by lower blood lactate concentration and higher amounts of fat oxidation. CONCLUSIONS: The results of the present study indicate that single-dose consumption of GTC influences oxidative stress biomarkers when compared between the GTC-NEX and GTC-EX groups, which could be beneficial for oxidative metabolism at rest and during exercise, possibly through the catechol-O-methyltransferase mechanism that is most often cited in previous studies.


Subject(s)
Catechin/pharmacology , Exercise , Oxidative Stress/drug effects , Rest , Tea/chemistry , 8-Hydroxy-2'-Deoxyguanosine , Antioxidants/pharmacology , Biomarkers/blood , Blood Pressure , Body Weight , Catechol O-Methyltransferase/metabolism , Creatinine/urine , Cross-Over Studies , Deoxyguanosine/analogs & derivatives , Deoxyguanosine/urine , Energy Intake , Energy Metabolism , Heart Rate , Humans , Lactic Acid/blood , Lipid Metabolism/drug effects , Male , Nutritive Sweeteners , Oxygen Consumption , Reactive Oxygen Species/metabolism , Young Adult
15.
Altern Med Rev ; 16(4): 348-54, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22214254

ABSTRACT

INTRODUCTION: The purpose of this study was to investigate the efficacy and safety of L-theanine as an aid to the improvement of objectively measured sleep quality in a population of 98 male children formally diagnosed with attention-deficit/hyperactivity disorder (ADHD). METHODS: A randomized, double-blind, placebo-controlled trial was conducted involving boys, ages 8-12 years, who had been previously diagnosed with ADHD. An experienced physician confirmed the diagnosis of ADHD in each subject. Randomization was stratified based upon current use of stimulant medication to ensure an equal distribution of stimulant/non-stimulant treated subjects into active and placebo treated groups. Participants consumed two chewable tablets twice daily (at breakfast and after school), with each tablet containing 100 mg of L-theanine (total 400 mg daily Suntheanine®, Taiyo Kagaku, Yokkaichi, Japan) or identical tasting chewable placebo for six weeks. Subjects were evaluated for five consecutive nights using wrist actigraphy at baseline, and again at the end of the six-week treatment period. The Pediatric Sleep Questionnaire (PSQ) was completed by parents at baseline and at the end of the treatment period. RESULTS: Actigraph watch data findings indicated that boys who consumed L-theanine obtained significantly higher sleep percentage and sleep efficiency scores, along with a non-significant trend for less activity during sleep (defined as less time awake after sleep onset) compared to those in the placebo group. Sleep latency and other sleep parameters were unchanged. The PSQ data did not correlate significantly to the objective data gathered from actigraphy, suggesting that parents were not particularly aware of their children's sleep quality. L-theanine at relatively high doses was well tolerated with no significant adverse events. CONCLUSIONS: This study demonstrates that 400 mg daily of L-theanine is safe and effective in improving some aspects of sleep quality in boys diagnosed with ADHD. Since sleep problems are a common co-morbidity associated with ADHD, and because disturbed sleep may be linked etiologically to this disorder, L-theanine may represent a safe and important adjunctive therapy in childhood ADHD. Larger, long-term studies looking at the wider therapeutic role of this agent in this population are warranted.


Subject(s)
Attention Deficit Disorder with Hyperactivity/drug therapy , Glutamates/therapeutic use , Sleep Wake Disorders/drug therapy , Actigraphy , Administration, Oral , Attention Deficit Disorder with Hyperactivity/complications , Child , Complementary Therapies , Double-Blind Method , Glutamates/administration & dosage , Humans , Male , Sleep Wake Disorders/complications , Surveys and Questionnaires , Treatment Outcome
16.
Chemistry ; 15(1): 219-26, 2009.
Article in English | MEDLINE | ID: mdl-19035604

ABSTRACT

We report that 2,6-naphthylene-bridged periodic mesoporous organosilicas exhibit unique fluorescence behavior that reflects molecular-scale periodicities in the framework. Periodic mesoporous organosilicas consisting of naphthalene-silica hybrid frameworks were synthesized by hydrolysis and condensation of a naphthalene-derived organosilane precursor in the presence of a template surfactant. The morphologies and meso- and molecular-scale periodicities of the organosilica materials strongly depend on the synthetic conditions. The naphthalene moieties embedded within the molecularly ordered framework exhibited a monomer-band emission, whereas those embedded within the amorphous framework showed a broad emission attributed to an excimer band. These results suggest that the naphthalene moieties fixed within the crystal-like framework are isolated in spite of their densely packed structure, different from conventional organosilica frameworks in which only excimer emission was observed for both the crystal-like and amorphous frameworks at room temperature. This key finding suggests a potential to control interactions between organic groups and thus the optical properties of inorganic/organic hybrids.

17.
Chemistry ; 14(36): 11529-38, 2008.
Article in English | MEDLINE | ID: mdl-19006167

ABSTRACT

Highly ordered mesoporous three-dimensional Ia3d silica (KIT-6) with different pore diameters has been synthesized by using pluronic P123 as surfactant template and n-butanol as cosolvent at different synthesis temperatures in a highly acidic medium. The materials were characterized by XRD and N(2) adsorption. The synthesis temperature plays a significant role in controlling the pore diameter, surface area, and pore volume of the materials. The material prepared at 150 degrees C, KIT-6-150, has a large pore diameter (11.3 nm) and a high specific pore volume (1.53 cm(3) g(-1)). We also demonstrate immobilization of lysozyme, which is a stable and hard protein, on KIT-6 materials with different pore diameters. The amount of lysozyme adsorbed on large-pore KIT-6 is extremely large (57.2 micromol g(-1)) and is much higher than that observed for mesoporous silicas MCM-41, SBA-15, and KIT-5, mesoporous carbons, and carbon nanocages. The effect of various parameters such as buffer concentration, adsorption temperature, concentration of the lysozyme, and the textural parameter of the adsorbent on the lysozyme adsorption capacity of KIT-6 was studied. The amount adsorbed mainly depends on solution pH, ionic strength, adsorption temperature, and pore volume and pore diameter of the adsorbent. The mechanism of adsorption on KIT-6 under different adsorption conditions is discussed. In addition, the structural stability of lysozyme molecules and the KIT-6 adsorbent before and after adsorption were investigated by XRD, nitrogen adsorption, and FTIR spectroscopy.


Subject(s)
Enzymes, Immobilized/chemistry , Silicon Dioxide/chemistry , Adsorption , Hydrogen-Ion Concentration , Muramidase/chemistry , Silicon Dioxide/chemical synthesis , Spectroscopy, Fourier Transform Infrared , Surface Properties , Temperature , X-Ray Diffraction
18.
Chem Commun (Camb) ; (7): 841-3, 2008 Feb 21.
Article in English | MEDLINE | ID: mdl-18253522

ABSTRACT

Amination of phenylene moieties in crystal-like mesoporous silica hybridized with phenylene is successfully achieved with close to 28% conversion of phenylene by a two-step chemical transformation process while preserving both the ordered mesostructure and crystal-like molecular scale periodicity of the parent material.


Subject(s)
Organosilicon Compounds/chemistry , Silicon Dioxide/chemistry , Amination , Crystallization , Molecular Structure , Organosilicon Compounds/chemical synthesis , Porosity , Powder Diffraction , Surface Properties
19.
Chem Commun (Camb) ; (2): 202-4, 2008 Jan 14.
Article in English | MEDLINE | ID: mdl-18092087

ABSTRACT

Organosilica porous solids containing chiral organic moieties in the framework with an enantiomeric purity of 95% ee, estimated by eluting organic constituent units from chiral organosilicas, were synthesized from a newly designed chiral (R)-(+)-1,2-bis(trimethoxysilyl)phenylethane precursor via a surfactant-mediated self-assembly approach.

20.
J Am Chem Soc ; 127(22): 8174-8, 2005 Jun 08.
Article in English | MEDLINE | ID: mdl-15926846

ABSTRACT

The bridged allylorganosilanes 1,4-bis(diallylethoxysilyl)benzene and 1,4-bis(triallylsilyl)benzene are presented as new precursors for the surfactant-assisted synthesis of ordered mesoporous organosilica with pore walls having crystal-like molecular-scale periodicity. This approach provides a new route to the formation of periodic mesostructures with crystal-like pore walls. The synthesis method presented is applicable to the preparation of mesoporous organosilica with bulky organic groups, the precursors of which are typically impossible to obtain in high purity.

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