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The article evaluates the suppressive effects of oolong tea extract and oolong tea-polymerized polyphenols (OTTP) on postprandial hypertriglyceridemia in rats and mice. According to the authors, lymphatic recovery of triglycerides in rats cannulated in the thoracic duct was delayed by the administration of oolong tea extract and more effectively than with green tea extract. They add OTTP also suppressed postprandial hypertriglyceridemia after administration of olive oil in mice.

The article compares the dietary effects of dihomo-γ-linolenic acid (DGLA) contained in the DGLA oil produced by a fungus with GLA on the fatty acid composition. The DGLA concentrations in the liver, serum, and brain of the DGLA group were higher than those of the GLA oil group. The results suggest that the dietary effect of DGLA would be more dominant than GLA.

To examine the effects of arachidonic acid (AA) on age-related cognitive deficits, Fischer 344 rats were given an AA-supplemented powder diet for 12 weeks from 18.6 months old as part of the old AA (OA) group. Other age-matched rats were fed a non-AA-supplemented powder diet as part of the old control (OC) group, and young rats were fed lab pellets as part of the young control (YC) group. When the aged rats reached 20.0 months old, all animals were tested for spontaneous activity in an open field, followed by the Morris water maze place and cue tasks. Escape latencies for the place task showed that the YC rats were fastest, and there was no difference between the OA and OC groups. However, the probe test and the first block of the cue task indicated that the OA rats remembered the location of an invisible platform better than the OC rats. Although the amount of hippocampal AA was larger in the OA rats than in the OC rats, the difference was not significant. The results showed that AA administration to aged animals may alleviate age-related deficits in spatial cognition. [ABSTRACT FROM AUTHOR]

Sesame lignans, which are biologically active compounds present in sesame seeds and oil, are known to have neuroprotective effects in several models of brain dysfunction. However, the effects of sesame lignans on age-related brain dysfunction are not clear and were thus investigated in the present study using a senescence-accelerated mouse (SAMP10). Two-month-old male SAMP10 mice were administrated a basal diet with 0% or 0.05% sesame lignans for two months, or with 0%, 0.02%, or 0.05% sesame lignans for 10 months and subjected to step-through passive avoidance tasks and forced swim tests. Reactive carbonyl species (RCs) were evaluated as markers of oxidative stress using a recently developed comprehensive analytical method. Both learning time in passive avoidance tasks and immobile time in forced swim tests became longer with aging (p < 0.05). However, the administration of sesame lignans significantly ameliorated age-related effects in both tests (p < 0.05). Age-related increases in RCs such as 4-hydroxy-2-nonenal in the cerebral cortex and liver were reduced in mice fed sesame lignans. These results suggest that sesame lignans can prevent age-related brain dysfunction via anti-oxidative activity. [ABSTRACT FROM AUTHOR]

Sesamin, a representative sesame lignan, has health-promoting activities. Sesamin is converted into catechol derivatives and further into their glucuronides or sulfates in vivo , whereas the biological activities of sesamin metabolites remain unclear. We examined the inhibitory effects of sesamin metabolites on the lipopolysaccharide (LPS)-induced nitric oxide (NO) production in mouse macrophage-like J774.1 cells and found that a monocatechol derivative SC1, (7α,7'α,8α,8'α)-3,4-dihydroxy-3',4'-methylenedioxy-7,9':7',9-diepoxylignane, has a much higher activity than sesamin and other metabolites. The inhibitory effects of SC1 glucuronides were time-dependently enhanced, associated with the intracellular accumulation of SC1 and the methylated form. SC1 glucuronides and SC1 attenuated the expression of inducible NO synthase (iNOS) and upstream interferon-β (IFN-β) in the LPS-stimulated macrophages. The inhibitory effects of SC1 glucuronides against NO production were canceled by the β-glucuronidase inhibitor and enhanced by the catechol- O -methyltransferase inhibitor. Our results suggest that SC1 glucuronides exert the anti-inflammatory effects by inhibiting the IFN-β/iNOS signaling through macrophage-mediated deconjugation.

We previously showed a prophylactic effect of Lactobacillus pentosus strain S-PT84 against oral candidiasis in mice. In the present study, we evaluated the protective effect of S-PT84 against Candida infection of the gastrointestinal tract. As the first step, we used an in vitro assay to compare the inhibitory effects of several lactobacilli (S-PT84 and Lactobacillus pentosus type strain JCM1558 T , Lactobacillus gasseri type strain JCM1131 T and Lactobacillus casei type strain JCM1134 T ) on mycelial growth of Candida albicans. S-PT84 directly adhered to Candida cells and showed the strongest growth-inhibitory activity among the tested Lactobacillus strains. In the second experiment, we used an in vivo assay to evaluate the effect of S-PT84 ingestion on severity score of stomach lesion and gastric inflammation in a mouse model of gastrointestinal candidiasis. The severity scores were significantly improved by oral administration of S-PT84 (6 mg/ 200 μL), consistent with decreased coverage of stomach lesions by patchy whitish plaques. The attenuation of stomach lesion severity by S-PT84 was more pronounced than that obtained with L. gasseri type strain JCM1131 T , consistent with the results of the above in vitro study. Histological analysis also indicated that S-PT84 prevented the adhesion of C. albicans to the stomach surface and suppressed stomach inflammation caused by neutrophil infiltration. Furthermore, S-PT84 also suppressed the vascular permeability observed in Candida-infected stomach. These results suggest that oral administration of S-PT84 might be effective not only in inhibiting Candida infection but also in preventing gastric inflammation induced by Candida infection.

Background: The aim of this study was to investigate the ability of a glucosamine-containing supplement to improve locomotor functions in subjects with knee pain., Methods: A randomized, double-blind, placebo-controlled, parallel-group comparative study was conducted for 16 weeks in 100 Japanese subjects (age, 51.8±0.8 years) with knee pain. Subjects were randomly assigned to one of the two supplements containing 1) 1,200 mg of glucosamine hydrochloride, 60 mg of chondroitin sulfate, 45 mg of type II collagen peptides, 90 mg of quercetin glycosides, 10 mg of imidazole peptides, and 5 μg of vitamin D per day (GCQID group, n=50) or 2) a placebo (placebo group, n=50). Japanese Knee Osteoarthritis Measure, visual analog scale score, normal walking speed, and knee-extensor strength were measured to evaluate the effects of the supplement on knee-joint functions and locomotor functions., Results: In subjects eligible for efficacy assessment, there was no significant group × time interaction, and there were improvements in knee-joint functions and locomotor functions in both groups, but there was no significant difference between the groups. In subjects with mild-to-severe knee pain at baseline, knee-extensor strength at week 8 (104.6±5.0% body weight vs 92.3±5.5% body weight, P=0.030) and the change in normal walking speed at week 16 (0.11±0.03 m/s vs 0.05±0.02 m/s, P=0.038) were significantly greater in the GCQID group than in the placebo group. Further subgroup analysis based on Kellgren-Lawrence (K-L) grade showed that normal walking speed at week 16 (1.36±0.05 m/s vs 1.21±0.02 m/s, P<0.05) was significantly greater in the GCQID group than in the placebo group in subjects with K-L grade I. No adverse effect of treatment was identified in the safety assessment., Conclusion: In subjects with knee pain, GCQID supplementation was effective for relieving knee pain and improving locomotor functions.

Sesamin has anti-oxidative functions in vivo. Fatigue is caused in part by oxidative stress. We evaluated whether sesame lignans (sesamin/episesamin=1/1, 10 mg) with vitamin E (55 mg of alpha-tocopherol) (SVE) could improve subjective statuses and anti-oxidative capacity in humans using questionnaires on fatigue, sleep and physical appearance, as well as low-density lipoprotein oxidation lag time. A placebo-controlled, double-blind, parallel-group study was conducted with subjects experiencing daily fatigue. After a run-in period, subjects were administered oral SVE or a placebo (P) for 8 weeks. A questionnaire regarding fatigue, sleep and physical appearance was conducted at 0, 4, and 8 weeks. Plasma low-density lipoprotein oxidation lag time was measured as an indicator of anti-oxidative capacity. The per-protocol analysis revealed significant improvements in fatigue status at 4 and 8 weeks compared to 0 weeks in both groups (p<0.01), and sleep and physical appearance at 8 weeks compared to 0 weeks only in the SVE group (p<0.01). There were no significant differences observed between the groups. According to the 72-subject subgroup analysis (aged 40 and over), the sleep and physical appearance significantly improved compared to the P group (p<0.05), and fatigue status showed a tendency for improvement compared to the P group. Anti-oxidative capacity in the SVE group significantly increased compared to the P group (p<0.01). No adverse events relating to SVE supplementation were confirmed. These results suggest SVE supplementation could safely alleviate daily fatigue and oxidative stress.

Episesamin is an isomer of sesamin, resulting from the refining process of non-roasted sesame seed oil. Episesamin has two methylendioxyphenyl groups on exo and endo faces of the bicyclic skeleton. The side methylendioxyphenyl group was metabolized by cytochrome-P450. Seven metabolites of episesamin were found in rat bile after treatment with glucuronidase/arylsulfatase and were identified using NMR and MS. The seven metabolites were (7α,7'β,8α,8'α)-3,4-dihydroxy-3',4'-methylenedioxy-7,9':7',9-diepoxylignane (EC-1-1), (7α,7'β,8α,8'α)-3,4-methylenedioxy-3',4'-dihydroxy-7,9':7',9-diepoxylignane (EC-1-2) and (7α,7'β,8α,8'α)-3,4:3',4'-bis(dihydroxy)-7,9':7',9-diepoxylignane (EC-2), (7α,7'β,8α,8'α)-3-methoxy-4-hydroxy-3',4'-methylenedioxy-7,9':7',9-diepoxylignane (EC-1m-1), (7α,7'β,8α,8'α)-3,4-methylenedioxy-3'-methoxy-4'-hydroxy-7,9':7',9-diepoxylignane (EC-1m-2), (7α,7'β,8α,8'α)-3-methoxy-4-hydroxy-3',4'-dihydroxy-7,9':7',9-diepoxylignane (EC-2m-1) and (7α,7'β,8α,8'α)-3,4-dihydroxy-3'-methoxy-4'-hydroxy-7,9':7',9-diepoxylignane (EC-2m-2). EC-1-1, EC-1-2 and EC-2 were also identified as metabolites of episesamin in human liver microsomes. These results suggested that similar metabolic pathways of episesamin could be proposed in rats and humans.

Nosocomial infections caused by microbial opportunistic infections or microbial biofilms may occur during hospitalization and increase patient morbidity, mortality and health care costs. Artificial antibiotic agents were initially used to prevent infection; however, the high prevalence of nosocomial infections has resulted in their excessive use, which has led to microbial resistance to these agents. The increase in microbial resistance to antibiotics and the development of antibiotic agents may be the cause of the production of other microbial resistance. Thus, natural compounds that have no adverse side effects would be a preferred treatment modality. Recently, the monosaccharide 1,5-anhydro-D-fructose (1,5-AF), a natural plant compound derived from starch, has been found to have multifunctional properties, including antioxidant, antiplatelet aggregation by thrombin and anti-inflammatory activities. The results of the present study demonstrate that 1,5-AF suppressed the growth of coagulase-negative staphylococci on the hands as well as the growth of Staphylococcus epidermidis, which is a cause of opportunistic infections. Furthermore, 1,5-AF suppressed biofilm formation by the methicillin-resistant Staphylococcus aureus. In conclusion, 1,5-AF is a natural compound that may be effective in preventing nosocomial infections, without causing adverse side effects.

Sesamin, one of the lignans contained in sesame, has been considered to have medicinal effects. It has been reported that sesamin suppressed the development of hypertension in rats. In this study, using a double-blind, cross-over, placebo-controlled trial, we investigated the effect of 4-wk administration of sesamin on blood pressure (BP) in mildly hypertensive humans. Twenty-five middle-aged subjects with mild hypertension were divided into two groups, matched by age and body mass index. Twelve subjects were allocated to 4-wk intake of capsules with 60 mg sesamin per day and 13 subjects to 4-wk intake of a placebo (period 1). After a 4-wk washout period, the subjects received the alternative administration for 4 wk (period 2). BP decreased with statistical significance with the administration of sesamin (systolic: 137.6+/-2.2 to 134.1+/-1.7 mmHg, p=0.044, diastolic: 87.7+/-1.3 to 85.8+/-1.0 mmHg, p=0.045), but little changed with the placebo (systolic: 135.0+/-1.8 to 135.1+/-1.7 mmHg, diastolic: 85.9+/-1.2 to 86.6+/-1.2 mmHg). In conclusion, 4-wk administration of 60 mg sesamin significantly decreased BP by an average of 3.5 mmHg systolic BP and 1.9 mmHg diastolic BP. These results suggest that sesamin has an antihypertensive effect in humans. Epidemiological studies suggested that a 2-3 mmHg decrease in BP reduces the rate of cardiovascular diseases; therefore, it is considered that BP reduction achieved by sesamin may be meaningful to prevent cardiovascular diseases.

The first chemical synthesis of two metabolites ((1R,2S,5R,6S)-6-(3,4-dihydroxyphenyl)-2-(3,4-methylenedioxyphenyl)-3,7-dioxabicyclo[3,3,0]octane (SC-1) and (1R,2S,5R,6S)-2,6-bis(3,4-dihydroxyphenyl)-3,7-dioxabicyclo[3,3,0]octane (SC-2)) of sesamin was achieved by a simple two-step approach from sesamin. The approach consists of acetoxylation of the methylenedioxy moiety(ies) with lead(IV) tetraacetate and acid hydrolysis of the resulting hemiorthoester to SC-1 and SC-2.

We have previously reported that substantial amounts of tocotrienols were present in the skin of animals fed a diet containing a tocopherols and tocotrienols rich fraction (T-mix) extracted from palm oil, and further, that sesame lignans enhanced tocotrienol levels in the skin. The present studies were undertaken to determine whether dietary tocotrienols and those with sesamin could protect the skin from damage induced by UVB irradiation in hairless mice fed four diets: a vitamin E-free diet, a 50 mg/kg alpha-tocopherol diet, a 229 mg/kg T-mix (with 50 mg alpha-tocopherol) diet and a 229 mg/kg T-mix with 2 g/kg sesamin diet. In Experiment 1, mice were fed the diets for 6 wk, and half of the mice were exposed to 180 mJ/cm(2 )of UVB light once daily for 7 d. After the intensity of sunburn was scored, vitamin E and thiobarbituric acid reactive substances (TBARS) concentrations in the skin and liver were determined. In Experiment 2, hairless mice were initiated with a single application of 7, 12-dimethylbenz[a]anthracene (DMBA), then 1 wk later mice were fed the experimental diets and subjected to 180 mJ/cm(2) UVB irradiation twice weekly for 20 wk. Tumor incidences were counted once a week. Tocotrienols were detected in the skin of mice fed T-mix, but their concentrations were significantly lower than for alpha-tocopherol. Sesamin elevated tocotrienol contents in the skin. In spite of the high alpha-tocopherol contents, the effects of alpha-tocopherol on sunburn and incidence of tumor were slight. T-mix fed groups reduced the extent of sunburn and incidence of tumor, and further reduction of sunburn and incidence of tumor were observed in the T-mix with sesamin group. These results suggest that dietary tocotrienols protect the skin more strongly than alpha-tocopherol against damage induced by UVB and sesamin enhances tocotrienol effects.

We compared the dietary effects of dihomo-gamma-linolenic acid (DGLA) contained in the DGLA oil produced by a fungus with gamma-linolenic acid (GLA) on the fatty acid composition. Wistar rats were fed with three kinds of oil for two weeks as follows: (i) control group: corn oil; (ii) GLA group: borage oil; (iii) DGLA group: DGLA oil/safflower oil = 55:45. The DGLA concentrations in the liver, serum, and brain of the DGLA group were higher than those of the GLA oil group. We also examined the dose effect of DGLA. The DGLA levels in the liver, serum, and brain significantly increased with increasing dosage of DGLA in the diet. DGLA administration significantly increased the ratio of PGE1/PGE2 in the rat plasma. The mechanism for GLA administration to improve atopic eczema is thought to involve an increase in the concentration of DGLA metabolized from GLA, so these results suggest that the dietary effect of DGLA would be more dominant than GLA.

Sesamin, a major lignan in sesame seeds and oil, has been known to lower blood pressure in several types of experimental hypertensive animals. A recent study demonstrated that sesamin metabolites had in vitro radical-scavenging activities. Thus, we determined whether the antioxidative effect of sesamin metabolites modulate the vascular tone and contribute to the in vivo antihypertensive effect of sesamin. We used four demethylated sesamin metabolites: SC-1m (piperitol), SC-1 (demethylpiperitol), SC-2m [(1R,2S,5R,6S)-6-(4-hydroxy-3-methoxyphenyl)-2-(3,4-dihydroxyphenyl)-3,7-dioxabicyclo[3,3,0]octane], and SC-2 [(1R,2S,5R, 6S)-2,6-bis(3,4-dihydroxyphenyl)-3,7-dioxabicyclo-[3,3,0]octane]. SC-1, SC-2m, and SC-2, but not SC-1m, exhibited potent radical-scavenging activities against the xanthine/xanthine oxidase-induced superoxide production. On the other hand, SC-1m, SC-1, and SC-2m produced endothelium-dependent vasorelaxation in phenylephrine-precontracted rat aortic rings, whereas SC-2 had no effect. The SC-1m- and SC-1-induced vasorelaxations were markedly attenuated by pretreatment with a nitric oxide synthase (NOS) inhibitor, NG-nitro-L-arginine (NOARG), or a soluble guanylate cyclase inhibitor, 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one. Neither SC-1m nor SC-1 changed the expression level of endothelial NOS protein in aortic tissues. The antihypertensive effects of sesamin feeding were not observed in chronically NOARG-treated rats or in deoxycorticosterone acetate-salt-treated endothelial NOS-deficient mice. These findings suggest that the enhancement of endothelium-dependent vasorelaxation induced by sesamin metabolites is one of the important mechanisms of the in vivo antihypertensive effect of sesamin.

Fifty-four polyphenols isolated from tea leaves were evaluated for their inhibitory activities against pancreatic lipase, the key enzyme of lipid absorption in the gut. (-)-Epigallocatechin 3-O-gallate (EGCG), which is one of major polyphenols in green tea, showed lipase inhibition with an IC50 of 0.349 microM. Moreover, flavan-3-ol digallate esters, such as (-)-epigallocatechin-3,5-digallate, showed higher activities of inhibition on lipase with an IC50 of 0.098 microM. On the other hand, nonesterified flavan-3-ols, such as (+)-catechin, (-)-epicatechin, (+)-gallocatechin, and (-)-epigallocatechin, showed zero and/or the lowest activities against pancreatic lipase (IC50 > 20 microM). These data suggested that the presence of galloyl moieties within the structure was required for enhancement of pancreatic lipase inhibition. It is well-known that flavan-3-ols are polymerized by polyphenol oxidase and/or heating in a manufacturing process of oolong tea. Oolonghomobisflavans A and B and oolongtheanin 3'-O-gallate, which are typical in oolong tea leaves, showed strong inhibitory activities with IC50 values of 0.048, 0.108, and 0.068 microM, respectively, even higher than that of EGCG. The oolong tea polymerized polyphenols (OTPP) were prepared for the assay from oolong tea extract, from which the preparation effectively subtracted the zero and/or less-active monomeric flavan-3-ols by preparative high-performance liquid chromatography. The weight-average molecular weight (Mw) and number-average molecular-weight (Mn) values of OTPP were 2017 and 903, respectively, by using gel permeation choromatography. OTPP showed a 5-fold stronger inhibition against pancreatic lipase (IC50 = 0.28 microg/mL) by comparison with that of the tannase-treated OTPP (IC50 = 1.38 microg/mL). These data suggested that the presence of galloyl moieties within their chemical structures and/or the polymerization of flavan-3-ols were required for enhancement of pancreatic lipase inhibition.

A novel stable precursor of ascorbic acid (vitamin C), 2-O-(beta-D-glucopyranosyl)ascorbic acid, was isolated from both the ripe fresh fruit and dried fruit of Lycium barbarum L., a plant of the Solanaceae family. The chemical structure was inferred by instrumental analyses and confirmed by chemical synthesis. The dried fruit of Lycium barbarum L. contained ca. 0.5% of it, which is comparable to the ascorbic acid content of fresh lemons. It increased the blood ascorbic acid by oral administration to rats, and it was also detected in blood from the portal vein.