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(1) Background: Arteriosclerosis is associated with high levels of low-density lipoprotein (LDL) cholesterol. O -methylated catechins in "Benifuuki" green tea are expected to reduce cholesterol levels, although there is limited research regarding this topic; (2) Methods: This trial evaluated 159 healthy volunteers who were randomized to receive ice cream containing a high-dose of "Benifuuki" extract including 676 mg of catechins (group H), a low-dose of "Benifuuki" extract including 322 mg of catechins (group L), or no "Benifuuki" extract (group C). Each group consumed ice cream (with or without extract) daily for 12 weeks, and their lipid-related parameters were compared; (3) Results: A significant reduction in the level of lectin-like oxidized LDL receptor-1 ligand containing ApoB (LAB) was detected in group H, compared to groups L and C. No significant differences between the three groups were detected in their levels of total cholesterol, triglycerides, and LDL cholesterol; (4) Conclusions: "Benifuuki" extract containing O -methylated catechins may help prevent arteriosclerosis.

Green tea and its major polyphenol epigallocatechin-3-O-gallate (EGCG) have suppressive effect on dietary obesity. However, it remains unsolved what type of diet on which they exhibit high or low anti-obesity effect. In the present study, we investigated whether anti-obesity effect of green tea differs depending on composition of fats or fatty acids that consist high-fat (HF) diet in mouse model. Green tea extract (GTE) intake dramatically suppressed weight gain and fat accumulation induced by olive oil-based HF diet, whereas the effects on those induced by beef tallow-based HF diet were weak. GTE also effectively suppressed obesity induced by unsaturated fatty acid-enriched HF diet with the stronger effect compared with that induced by saturated fatty acid-enriched HF diet. These differences would be associated with the increasing action of GTE on expression of PPARδ signaling pathway-related genes in the white adipose tissue. Expressions of genes relating to EGCG signaling pathway that is critical for exhibition of physiological effects of EGCG were also associated with the different effects of GTE. Here, we show that anti-obesity effect of GTE differs depending on types of fats or fatty acids that consist HF diet and could be attenuated by saturated fatty acid.

Aims: We previously reported that apple polyphenols (AP) and their major active components, procyanidins, had beneficial effects on glucose homeostasis and diabetes in diabetic ob/ob mice. The present study was performed to evaluate the effects of chronic AP administration on glucose tolerance in high-normal and borderline human subjects., Methods: Subjects (n=65) with a fasting plasma glucose (FPG) level of 100-125mg/dL determined during a recent health check-up were randomised to receive tablets containing AP (600mg/day) or placebo tablets for 12weeks in a double-blinded, placebo-controlled clinical trial. The primary outcome was insulin resistance, assessed using a 75g oral glucose tolerance test (OGTT)., Results: The 12-week chronic administration of AP significantly reduced the increase in glucose at 30-min post-75g OGTT (OGTT 30-min glucose ) value, compared to the placebo regimen. Furthermore, in a subgroup of the high-normal (FPG value, 100-109mg/dL; 2-h post-75g OGTT glucose (OGTT 2-h glucose ) value, <140mg/dL) and borderline (FPG value, 110-125mg/dL; OGTT 2-h glucose value, <140mg/dL and FPG value, <126mg/dL; OGTT 2-h glucose value, 140-199mg/dL) subjects, OGTT 30-min glucose value in the AP group (164.0±7.4mg/dL) was significantly lower than that of the placebo group (194.7±10.4mg/dL, p<0.05). No significant changes in the other lipid parameters and cytokine levels were observed., Conclusions: Chronic AP administration significantly improved impaired glucose tolerance in high-normal and borderline subjects. Larger and/or longer-term scale human studies are required to confirm the potential glucose homeostasis of AP., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Japan is a major tea producing country, and green tea is known for its health benefits which are believed to be due to catechins. However, difficulties in maintaining an adequate amount of catechins in the blood have been reported. Another important health-promoting activity among the Japanese is bathing in hot springs. This pilot study examined whether the combined effects of green tea consumption and hot spring bathing improved absorption of green tea catechins. The study, with a comparative within-subject design involving two different intervention trials--green tea consumption with hot spring bathing and only green tea consumption--was conducted on 2 separate days. Plasma levels of catechin; (-)-epigallocatechin-3-O-gallate (EGCG) were analyzed from four volunteers. Plasma EGCG concentration was found to be higher for the combined trial of green tea consumption and hot spring bathing., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

We investigated the effects of extracts of Benifuuki (a tea cultivar that contains methylated catechins such as epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3"Me)) in mice fed a high-fat/high-sucrose (HF/HS) diet. This tea cultivar was then compared with an extract of Yabukita (a popular tea cultivar that lacks methylated catechins). For 6 weeks, C57BL/6J mice were fed either HF/HS diet with or without tea extracts from tea cultivars, which contained almost identical ingredients except for methylated catechins (i.e., Yabukita (0.2% and 1%) or Benifuuki (0.2% and 1%) extract powders). Supplementation with Benifuuki 0.2% markedly lowered plasma levels of TG and NEFAs compared with mice supplemented with Yabukita 0.2%. The diet containing Benifuuki 1% decreased adipose tissue weights, liver TG, and expression of lipogenic genes in the liver. These results suggested that Benifuuki had much greater lipid-lowering effects than Yabukita. Taken together, these data suggest that methylated catechins direct the strong lipid-lowering activity of Benifuuki.

Delphinidin-3-O-galactoside (D3G) is a water-soluble anthocyanin with antioxidant activity. (-)-Epigallocatechin-3-gallate (EGCG) is also known as a powerful antioxidant but concomitantly possesses a prooxidative property. We hypothesized that D3G is capable of protecting the EGCG-induced cytotoxicity and endoplasmic reticulum (ER) stress via inducing self-protective proteins and antioxidant enzymes. (-)-Epigallocatechin-3-gallate (200-500 μM) dose dependently decreased the viability of hepa1c1c-7 mouse hepatocytes, whereas D3G (50-500 μM) did not change it. Pretreatment with D3G significantly suppressed EGCG-induced cytotoxicity in a time-dependent manner (0, 6, and 24 hours). (-)-Epigallocatechin-3-gallate drastically decreased heme oxygenase-1 and heat shock protein 70 messenger RNA (mRNA) levels, whereas, pretreatment with D3G markedly attenuated their down-regulations. Delphinidin-3-O-galactoside remarkably decreased EGCG-induced ER stress responses such as C/EBP-homologus protein mRNA expression and X-box-binding protein-1 mRNA splicing. Taken together, our data suggest that D3G is capable of masking the EGCG-induced cytotoxicity and ER stress, presumably through up-regulation of antioxidant enzymes and heat shock proteins., (Copyright © 2012 Elsevier Inc. All rights reserved.)

We attempted to improve the bioavailability of green tea catechins by using food ingredients. The catechin bioavailability of a green tea extract administered to mice was significantly (p<0.05) increased by supplementing with steamed rice. This enhanced bioavailability was due to the increased concentration of plasma non-gallated catechins, especially epigallocatechin (EGC).

Benifuuki is a tea cultivar with an antiallergic effect stronger than that of Yabukita tea, the most popular green tea cultivar consumed in Japan. The effective compound is (-)-epigallocatechin-3-O-(3-O-methyl)gallate (EGCG3''Me), an O-methylated derivative of EGCG. This study examined the antihypertensive effects of EGCG3''Me and Benifuuki tea. First, it was determined that EGCG3''Me has a significant inhibitory effect on the activity of angiotensin I-converting enzyme (ACE). Second, clinical trials showed that Benifuuki tea suppressed high blood pressure to a greater extent than green tea that did not contain EGCG3''Me after equal amounts of tea catechins were consumed for 8 weeks. The effect of Benifuuki tea on human hypertension is mainly the result of the strong inhibitory effect of EGCG3''Me on ACE activity, its high rate of absorption, and its stability in the blood.

Background: Tea (Camellia sinensis L.) is consumed all over the world and in especially large quantities in Japan and China, where it has been used not only as a daily beverage but also for medicinal purposes for thousands of years. Tea has been found to exhibit various bioregulatory activities, including antiallergic, anticarcinogenic, antimetastatic, antioxidative, antihypertensive, antihypercholesterolemic, anti-dental caries and antibacterial effects, and to influence intestinal flora., Results: Cha Chuukanbohon Nou 6 is a tea cultivar improved by the National Institute of Vegetable and Tea Science (NIVTS) in Japan. On comparing chemical constituents of 11 varieties of tea leaves by high-performance liquid chromatography, we found two new major compounds in Cha Chuukanbohon Nou 6. Nuclear magnetic resonance spectroscopy revealed these compounds to be theogallin and 1,2-di-O-galloyl-4,6-O-(S)-hexahydroxydiphenoyl-beta-D-glucopyranose. The two were similar in chemical structure to strictinin, an inhibitor of immunoglobulin (Ig) production. Thus their effects on the production of Igs by peripheral blood lymphocytes were tested. Both compounds, like strictinin, inhibited IgE production., Conclusion: The results suggest Cha Chuukanbohon Nou 6 to be the basis of an antiallergic beverage., (Copyright (c) 2009 Society of Chemical Industry.)

To identify the immunostimulants included in green tea extract, we investigated a crude tea polysaccharide related to increases in phagocytic activity using macrophage-like cells, and found that the crude tea polysaccharide from immature tea leaves included many RNAs as compared with that from mature tea leaves. Furthermore, the crude tea polysaccharide increased phagocytosis through toll-like receptor 7.

Background: We previously reported that 'benifuuki' green tea containing O-methylated catechin significantly relieved the symptoms of perennial or seasonal rhinitis compared with a placebo green tea that did not contain O-methylated catechin in randomized double-blind clinical trials. In this study we assessed the effects of 'benifuuki' green tea on clinical symptoms of seasonal allergic rhinitis., Methods: An open-label, single-dose, randomized, parallel-group study was performed on 38 subjects with Japanese cedar pollinosis. The subjects were randomly assigned to long-term (December 27, 2006-April 8, 2007, 1.5 months before pollen exposure) or short-term (February 15, 2007: after cedar pollen dispersal--April 8, 2007) drinking of a 'benifuuki' tea drink containing 34 mg O-methylated catechin per day. Each subject recorded their daily symptom scores in a diary. The primary efficacy variable was the mean weekly nasal symptom medication score during the study period., Results: The nasal symptom medication score in the long-term intake group was significantly lower than that of the short-term intake group at the peak of pollen dispersal. The symptom scores for throat pain, nose-blowing, tears, and hindrance to activities of daily living were significantly better in the long-term group than the short-term group. In particular, the differences in the symptom scores for throat pain and nose-blowing between the 2 groups were marked., Conclusions: We conclude that drinking 'benifuuki' tea for 1.5 months prior to the cedar pollen season is effective in reducing symptom scores for Japanese cedar pollinosis.

We investigated effects of various tea infusions on mast cell activation using mouse mast cells. Among various tea extracts, infusions from cultivar 'Benihomare' and Taiwan lineage strongly inhibited histamine release after Fc epsilon RI cross-linking. Among three types of tea (from cultivar 'Benihomare'), extract from oolong tea or black tea inhibited histamine release more strongly than green tea extract. Furthermore, 'Benihomare' oolong tea extract suppressed tyrosine phosphorylation of cellular proteins after Fc epsilon RI cross-linking, but polyvinyl polypyrrolidone treatment of the extract to remove phenolic compounds, weakened the suppressive effect.