The Impact of Purple-Flesh Potato (Solanum tuberosum L.) cv. "Shadow Queen" on Minor Health Complaints in Healthy Adults: A Randomized, Double-Blind, Placebo-Controlled Study.

The purple-flesh potato (Solanum tuberosum L.) cultivar "Shadow Queen" (SQ) naturally contains anthocyanins. This randomized, double-blind, placebo-controlled study determines whether ingesting purple potatoes increases the number of mesenchymal stem cells (MSC) and improves stress response, a minor health complaint in healthy adults (registration number: UMIN000038876). A total of 15 healthy subjects (ages: 50-70 years) with minor health complaints were randomly assigned to one of two groups. For 8 weeks, the placebo group received placebo potatoes cv. "Haruka" and the test group received test potato cv. SQ containing 45 mg anthocyanin. The MSC count and several stress responses were analyzed at weeks 0 and 8 of the intake periods. The ingestion of a SQ potato did not affect the MSC count but markedly improved psychological stress response, irritability, and depression as minor health complaints compared with "Haruka". No adverse effects were noted. Hence, an 8-week intake of SQ could improve stress responses.

Administration of Apple Polyphenol Supplements for Skin Conditions in Healthy Women: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

This clinical study was performed to evaluate the effects of continuous apple polyphenol (AP) administration on facial skin conditions and pigmentation induced by ultraviolet (UV) irradiation in healthy women participants. Participants (n = 65, age 20-39 years) were randomized to receive tablets containing AP (300 or 600 mg/day) or placebo in a double-blinded, placebo-controlled clinical trial. Continuous administration of AP for 12 weeks significantly prevented UV irradiation induced skin pigmentation (erythema value, melanin value, L value), although a dose-dependent relationship was not clearly observed. In contrast, no significant differences were detected between the groups with regard to water content and trans-epidermal water loss. Our study demonstrated that APs and their major active compounds, procyanidins, have several health benefits. Here, we report that continuous administration of AP for 12 weeks alleviated UV irradiation induced skin pigmentation, when compared with placebo, in healthy women.

Chronic administration of apple polyphenols ameliorates hyperglycaemia in high-normal and borderline subjects: A randomised, placebo-controlled trial.

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 (OGTT30-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 (OGTT2-h glucose) value, <140mg/dL) and borderline (FPG value, 110-125mg/dL; OGTT2-h glucose value, <140mg/dL and FPG value, <126mg/dL; OGTT2-h glucose value, 140-199mg/dL) subjects, OGTT30-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.

Regression of atherosclerosis with apple procyanidins by activating the ATP-binding cassette subfamily A member 1 in a rabbit model.

BACKGROUND AND AIMS: Apple polyphenol contains abundant procyanidins, which have been associated with an anti-atherosclerosis and cholesterol-lowering effect. The aim of this study was to investigate whether apple procyanidins (APCs) feature therapeutic efficacy in terms of regressing atherosclerosis and whether this efficacy is due to mechanisms other than a cholesterol-lowering effect. METHODS: After eight weeks on an atherogenic diet, rabbits were given a normal diet for another eight weeks to normalize the increased serum lipids level. The rabbits in the baseline group were sacrificed at this stage. The control group was subsequently fed a normal diet for eight weeks, while the APCs group was administrated 50 mg/kg/day of APCs in addition to the normal diet. Serum lipids and aortic intimal-medial thickness (IMT) were serially examined, and the resected aorta was examined histologically and through molecular biology. RESULTS: Aortic IMT on ultrasonography and the lipid accumulation area examined using Sudan IV staining were significantly reduced in the APCs group as compared to the control group. Serum lipid profiles were not different between the groups. Immunohistochemistry showed significantly decreased staining of an oxidative stress marker and significantly increased staining of ATP-binding cassette subfamily A member 1 (ABCA1) in the APCs group. Western blotting and RT-PCR also showed increased expression of ABCA1 mRNA and its protein in the APCs group. CONCLUSIONS: This study revealed that APCs administration causes a regression of atherosclerosis. APCs might hold promise as an anti-atherosclerotic agent.

Oral Administration of Apple Procyanidins Ameliorates Insulin Resistance via Suppression of Pro-Inflammatory Cytokine Expression in Liver of Diabetic ob/ob Mice.

Procyanidins, the main ingredient of apple polyphenols, are known to possess antioxidative and anti-inflammatory effects associated closely with the pathophysiology of insulin resistance and type 2 diabetes. We investigated the effects of orally administered apple procyanidins (APCs) on glucose metabolism using diabetic ob/ob mice. We found no difference in body weight or body composition between mice treated with APCs and untreated mice. A 4 week oral administration of APCs containing water [0.5% (w/v)] ameliorated glucose tolerance, insulin resistance, and hepatic gluconeogenesis in ob/ob mice. APCs also suppressed the increase in the level of the pancreatic ß-cell. Insulin-stimulated Akt phosphorylation was significantly enhanced; pro-inflammatory cytokine expression levels were significantly decreased, and c-Jun N-terminal kinase phosphorylation was downregulated in the liver of those mice treated with APCs. In conclusion, APCs ameliorate insulin resistance by improving hepatic insulin signaling through suppression of hepatic inflammation in ob/ob mice, which may be a mechanism with possible beneficial health effects of APCs in disturbed glucose metabolism.

Characterization and activity of anthocyanins in Zijuan tea (Camellia sinensis var. kitamura).

Zijuan tea is a new cultivar produced in Yunnan province of China. Unlike most tea cultivars, Zijuan tea is anthocyanin-rich. The composition and antioxidant activities of anthocyanins of Zijuan tea were studied for the first time in this paper. Anthocyanins were extracted with acidified methanol and quantified as 707 ± 28 µg/g of dry weight (cyanidin-3-O-ß-D-glucoside equivalent) by high-performance liquid chromatography (HPLC) analysis. Four anthocyanins were successfully identified after Amberlite XAD-7HP adsorption column chromatography and octadecyl silane (ODS) flash chromatography. Among the four, delphinidin-3-O-ß-D-galactoside (1) and cyanidin-3-O-ß-D-galactoside (2) were confirmed by liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) and HPLC. Delphinidin-3-O-ß-D-(6-(E)-p-coumaroyl) galactopyranoside (3) and cyanidin-3-O-ß-D-(6-(E)-p-coumaroyl) galactopyranoside (4) were characterized by the high-resolution time-of-flight-mass spectrometry (HRTOF-MS) and nuclear magnetic resonance (NMR) spectrometry. The antioxidant activities of compounds 3 and 4, which composed approximately 75% of the total anthocyanins content in HPLC analysis, were evaluated by DPPH and FRAP assays. Results showed that both had higher antioxidant activities than commercial antioxidants butylated hydroxytoluene (BHT) used as one of controls in these assays.

Cloning of a novel O-methyltransferase from Camellia sinensis and synthesis of o-methylated EGCG and evaluation of their bioactivity.

The gene of a novel O-methyltransferase was isolated from tea cultivars (Camellia sinensis L.). Using the recombinant enzyme, O-methylated (-)-epigallocatechin-3-O-gallate (EGCG) in all cases were synthesized. EGCG and the synthesized O-methylated EGCGs including (-)-epigallocatechin-3-O-(3-O-methyl)-gallate (EGCG3''Me), (-)-epigallocatechin-3-O- (4-O-methyl)-gallate(EGCG4''Me), (-)-epigallocatechin-3-O-(3,5-O-dimethyl)-gallate (EGCG3'',5''diMe), and (-)-3-O-methyl-epigallocatechin-3-O-(3,5-O-dimethyl)-gallate (EGCG3',3'',5''triMe) were assayed using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay and antibacterial activity. EGCG was the most effective of the O-methylated EGCGs. The antiallergic effects of EGCG and the other O-methylated EGCGs were measured by conducting histamine release assays using bone marrow-derived mouse mast cells, and the order of potency was EGCG3',3'',5''triMe = EGCG3'',5''diMe > EGCG3''Me > EGCG. These results indicated that reducing the number of hydroxyl groups decreases the effectiveness of DPPH radical scavenging and antibacterial activity. In contrast, the inhibition of histamine release was potentiated by an increase in the number of methyl groups in EGCG, especially in the galloyl moiety.

Regulation of vascular endothelial function by procyanidin-rich foods and beverages.

Flavonoid-rich diets are associated with a lower mortality from cardiovascular disease. This has been linked to improvements in endothelial function. However, the specific flavonoids, or biologically active metabolites, conferring these beneficial effects have yet to be fully defined. In this experimental study of the effect of flavonoids on endothelial function cultured endothelial cells have been used as a bioassay with endothelin-1 (ET-1) synthesis being measured an index of the response. Evaluation of the relative effects of extracts of cranberry juice compared to apple, cocoa, red wine, and green tea showed inhibition of ET-1 synthesis was dependent primarily on their oligomeric procyanidin content. Procyanidin-rich extracts of cranberry juice triggered morphological changes in endothelial cells with reorganization of the actin cytoskeleton and increased immunostaining for phosphotyrosine residues. These actions were independent of antioxidant activity. Comparison of the effects of apple procyanidin monomers through heptamer showed a clear structure-activity relationship. Although monomer, dimer, and trimer had little effect on ET-1 synthesis, procyanidin tetramer, pentamer, hexamer, and heptamer produced concentration-dependent decreases with IC(50) values of 5.4, 1.6, 0.9, and 0.7 microM, respectively. Levels of ET-1 mRNA showed a similar pattern of decreases, which were inversely correlated with increased expression of Kruppel-like factor 2 (KLF2), a key endothelial transcription factor with a broad range of antiatherosclerotic actions including suppression of ET-1 synthesis. Future investigations of procyanidin-rich products should assess the role KLF2 induction plays in the beneficial vascular effects of high flavonoid consumption.