Black tea in chemo-prevention of cancer and other human diseases

Tea is the most popular functional beverage in the world and has been gaining more and more attention for its health beneficial properties.Among common teas,black tea is consumed more than green tea and oolong tea worldwide.Numerous studies have shown the biological activities of black tea and its polyphenols that include anti-oxidant,anti-tumor,anti-inflammation and metabolic regulation.Tea polyphenols such as theaflavins and catechins are considered to be multifunctional compounds that could be effective in the prevention or treatment of various cancers,cardiovascular disease,chronic inflammation,obesity,metabolic syndrome,and neurodegenerative diseases.In this review,we summarized the up-to-date research and underlying molecular mechanisms of black tea and its polyphenols.©2013 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved.

Inhibition of citrus flavonoids on 12-O-tetradecanoylphorbol 13-acetate-induced skin inflammation and tumorigenesis in mice

The inhibitory effects of a formulated product from citrus peel extract,Gold Lotion(GL),on 12-O-tetradecanoylphorbol 13-acetate(TPA)-induced expression of inducible nitric oxide synthase(iNOS)and cyclooxygenase-2(COX-2)in mouse skin was reported in this study.It is found that in the TPA-induced skin inflammation model,the topical application of GL effectively inhibited the transcriptional activation of iNOS and its mRNA and protein in mouse skin.It is also discovered that GL significantly inhibited TPA-induced mouse skin inflammation by decreasing inflammatory gene parameters.Furthermore,GL dramatically inhibited 7,12-dimethylbenez[a]anthracene(DMBA)/TPA-induced skin tumor formation and reduced tumor incidence,tumor weight and tumor multiplicity of papillomas at 20 weeks.In essence,these in vivo data have revealed that GL is an effective anti-tumor agent that functions by down-regulating the protein levels of COX-2,ornithine decarboxylase(ODC),and vascular endothelial growth factor(VEGF)in mouse skin,suggesting that GL is a novel functional natural product capable of preventing inflammation-associated tumorigenesis.©2012 Production and hosting by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.

Chemistry and health beneficial effects of oolong tea and theasinensins

Among six major types of tea(white,green,oolong,yellow,black,and dark teas)from Camellia sinensis,oolong tea,a semi-fermented tea,with its own unique aroma and taste,has become a popular consumption as indicated by the increasing production.Representing the characteristic flavonoids of oolong tea,theasinensins are dimeric flavan-3-ols.Many recent studies have indicated that oolong tea and theasinensins possess several health benefit properties.We consider it significant and necessary to have a comprehensive review in the recent advances of oolong tea.Therefore,the aim of the present review is to provide a new perspective on oolong tea and its characteristic phytochemicals,theasinensins associated with health benefits,molecular action pathway,and chemical mechanism of theasinensin formation from scientific evidences available on the literature.Furthermore,the chemical characterization of the oxidation products and the model oxidation system to the chemical changes of theasinensins are also discussed.

The effects of the extract of oolong tea and its metabolites from Andraca theae in high fat diet induced obese Wistar rat

Obesity is a critical health issue worldwide.For a long time,the concept of drinking tea for health and pleasure is widely accepted.The strain of Andraca theae lives on the tea leaf and the bioactivity of its metabolites in the feces is unknown yet.Thus,the objective of this study was to investigate whether the extract of tea(Taiwan Tea Experiment Station No.12(TE))and its metabolites from Andraca theae(TME)could prevent obesity in the high fat diet-induced obese rats.Our results showed that TE had higher concentrations of epigallocatechin gallate(EGCG)and caffeine than that from TME.TE significantly decreased abdominal adipose tissue,especially epididymal fat via increasing preadipocyte factor 1(Pref-1),SRY(sex determining region Y)-box 9(SOX-9)and decreasing peroxisome proliferator-activated receptorγ(PPARγ),CCAAT/enhancer binding protein(C/EBP)β,C/EBPαand C/EBPβprotein expression.Taken together,these results suggest that the content of tea polyphenols in TE play an important role for alleviating abdominal fat.

The feasibility study of natural pigments as food colorants and seasonings pigments safety on dried tofu coloring

In order to improve appetite,attract consumers and even conform to the food culture,food coloring has become one of the necessary links in modern food processing.For example,dried-tofu will be colored by adding artificial food colors(AFCs)such as sunset yellow,cochineal red A or other seasonings like soy sauce.However,the dispute persists about whether AFCs are harmful to health.Some studies indicate AFCs affect children’s intelligence and attention,cause hyperactivity,and allergy when children consumed≥50 mg.In addition,researches showed that chemical soy sauce produces a trace of methylglyoxal(MGO)in the manufacturing process,which is related to diseases such as oxidative stress,diabetes,and cognitive deterioration.Therefore,natural pigments are relatively new and promising strategy for replacing high-risk AFCs.Thus,the objective of this study was to use dried-tofu as a natural colorants coloring screening platform,through the concept of three primary colors to discuss the coloring effects of natural colorants in Taiwan in double–phase(liquid phase to solid phase)food coloring system and assess the effects of MGO on PC12 neuron cellular morphology and cell cycle at the dietary exposure in soy sauce.Our results showed that formula G:R=0.2:0.8 and C:R=0.08:0.92 were coloring by combined natural colorants had the same eye sensory quality acceptance of consumer and had the intention to purchase.Furthermore,the results from the PC12 cell suggested that dietary exposure of methylglyoxal(<50M)in soy sauce did not affect neuron cellular morphology and cell cycle significantly.Overall,Gardenia Yellow,Curcumin,and Radish Red could overcome the application restrictions in multiplephase food coloring system and simultaneously soy sauce as a coloring agent was safety.It showed the possibility of them as food colorants on dried-tofu.

Effects of ginseng dietary supplementation on a high-Fat diet-induced obesity in C57BL/6 Mice

Excess caloric intake increases the amount of adipose tissue and contributes to metabolic disorders in disrupted metabolic homeostasis.This study aimed to investigate the anti-obesity effects of ginseng and the alternation of gut microbiota composition in high-fat diet(HFD)-induced obesity.The results showed that HFD treatment influenced body weight gain,adipose tissue accumulation and biochemical parameter changes.Compared to the HFD group,ginseng supplementation of HFD-fed mice decreased body weight,adipose tissue mass,total cholesterol(T-CHO)and high-density lipoprotein(HDL)/low-density lipoprotein(LDL)ratio.To analysis the alterations of gut microbiota,ginseng in dietary supplements decreased Firmicutes abundance and increased Bacteroidetes abundance.Taken together,these findings suggest ginseng may modulate the energy storage and alter gut microbiota composition.

Quercetin inhibits truncated isoform of dopamine-and cAMP-regulated phosphoprotein as adjuvant treatment for trastuzumab therapy resistance in HER2-positive breast cancer

Trastuzumab resistance is one of the causes of poor prognosis in patients with human epidermal growth factor receptor 2(HER2)-positive(HER2+)breast cancer(BC).The truncated isoform of dopamine-and cAMPregulated phosphoprotein(t-DARPP)has been reported to be involved in trastuzumab therapy resistance and promoting tumor progression.To evaluate the t-DARPP expression in BC,paired tumors and surrounding normal tissues were analyzed by real-time polymerase chain reaction and confirmed higher DARPP-32 kDa family mRNA expression in HER2+BC tumor tissues.We established 2 patient-derived xenografts(PDX)mice models to test the efficacy of trastuzumab,named model 1(non-responder)and model 2(responder).t-DARPP and p95-HER2 protein-protein interactions were detected in PDX tumor tissue from non-responders using Förster resonance energy transfer assays.Instead,there is no response from the responder.Furthermore,mechanistic studies using transwell and western blot assays demonstrated that t-DARPP could upregulate epithelial-mesenchymal transition signaling proteins,enhance p95-HER2 expression and promote cell migration.We found that quercetin effectively reduced t-DARPP expression in HER2+BC cells.In t-DARPP ShRNA-suppressed cells,quercetin synergistically enhanced trastuzumab-induced apoptotic cell death and G2/M phase arrest.In conclusion,the combination of quercetin and trastuzumab treatment by targeting t-DARPP in HER2+BC patients has the potential as a biomarker for mitigating drug resistance.