To explore the mechanism of tea albino variation and high theanine formation, 'Fuyun 6' and a new theanine-rich tea cultivar 'Fuhuang 2' were as materials in this study, pigment content, metabolome and transcriptome of the two cultivars were analyzed by ultramicroelectron microscopy, widely targeted metabolomics, targeted metabolomics and transcriptomics. The results showed that five catechins, theobromine, caffeine, and 20 free amino acids, including theanine, glutamine, arginine, etc., were identified by targeted metabolomics. The amino acid content of 'Fuhuang 2' was significantly higher than that of 'Fuyun 6', and the theanine content was as high as 57.37 mg/g in 'Fuhuang 2'. The ultrastructure of leaves showed that the chloroplast cell structure of 'Fuhuang 2' was fuzzy, most of the grana lamellae were arranged in disorder, with large gaps, and the thylakoids were filiform. The determination of pigments showed that compared with 'Fuyun 6', the contents of chlorophyll A and B, carotenoids, flavonoids and other pigments of 'Fuhuang 2' decreased significantly, some important pigment-related-genes, such as chlorophyllase (CLH), 9-cis-epoxycarotenoid dioxygenase (NCED), flavonoid 3β-hydroxylase (F3H) and flavonoid 3', 5'-hydroxylase (F3'5'H) were significantly changed. Compared with 'Fuyun 6', 'Fuhuang 2' identified 138 significantly changed metabolites (SCMs) and 658 differentially expressed genes (DEGs). KEGG enrichment analysis showed that SCMs and DEGs were significantly enriched in amino acid biosynthesis, glutathione metabolism and TCA cycle. In general, the albino phenotype of 'Fuhuang 2' may be caused by a deficiency in photosynthetic proteins, chlorophyll metabolism genes and chlorophyll content. The accumulation of high theanine in 'Fuhuang 2' may be due to the low nitrogen consumption in yellowed leaves and the lack of carbon skeleton, amino and nitrogen resources are stored more effectively, resulting in the up regulation of metabolites and related gene expression in the amino acid synthesis pathway, theanine has become a significant accumulation of nitrogen-containing compounds in yellowed leaves.
Camellia sinensis/genetics* ; Chlorophyll A/metabolism* ; Plant Proteins/genetics* ; Plant Leaves/chemistry* ; Chlorophyll/metabolism* ; Transcriptome ; Flavonoids/metabolism* ; Amino Acids/genetics* ; Tea ; Mixed Function Oxygenases/metabolism* ; Nitrogen/metabolism*

The tea beverages will be endowed with distinct aroma and taste, as well as various biologically active compounds including probiotic factors, when fermented with lactic acid bacteria (LAB). However, at present, few studies on the dynamics of flavors in tea soup at different fermentation stages were conducted. In this study, the composition of monosaccharides, aromatic components, free amino acids, and organic acids were measured, when the black tea beverages were fermented with Lactobacillus coryniformis FZU63 which was isolated from Chinese traditional kimchi. The results indicated that monosaccharides including glucose, fructose, mannose and xylose in black tea beverages are the main carbon sources for fermentation. In addition, the abundance of aromatic compounds in black tea soup are increased significantly at different fermentation stages, which endow the fermented black tea soup with fruit aroma on the basis of flowery and nutty aroma. Moreover, some bitter amino acids are reduced, whereas the content of sweet and tasty amino acids is elevated. Furthermore, the levels of lactic acid, malic acid, citric acid and other organic acids are accumulated during the fermentation. Additionally, sensory evaluation displays that black tea beverage is acquired with comprehensive high-quality after being fermented for 48 h. This study provides a theoretical basis to steer and control the flavor formation and quality of the fermented tea beverages during LAB fermentation.
Tea/chemistry* ; Beverages/microbiology* ; Camellia sinensis ; Fermentation ; Acids ; Amino Acids ; Glucose

The present study compared active ingredients of tea from different sources to select tea type and the fraction of tea extracts for the highest anti-hyperglycemic activity, and to verify anti-hyperglycemic activity of the selected tea extract. Tea extracts were separated and enriched by molecular weight using ultra-filtration technology. The extracts were first screened by -glucosidase inhibition assay, followed by using a rat inverted intestine sac system to measure the effect on glucose transport. Both alloxan-induced diabetic rat model and high-fat diet combined with streptozotocin-induced rat diabetes mellitus model were used to study the effects of active components on blood glucose, body weight, insulin resistance. The experimental results showed that the different kinds of tea extracts had different inhibitory effects on -glucosidase, and the inhibitory effect of tea extract E on -glucosidase was stronger. The effects of different components of tea extract E also varied greatly, of which Fraction AN protein had stronger inhibitory effect on -glucosidase than other fragments, and Fraction AN protein had a strong inhibitory effect on glucose transport, reduced blood sugar and normalized insulin secretion in diabetic rats. The results suggest that a glycol-protein fraction(AN) from the extracts might be responsible for the anti-hyperglycemic activity of tea polysaccharides. The AN glycol-protein fraction has strong inhibitory effects on both -glucosidase activity and glucose transport by the small intestine. It also reduced blood glucose level and normalized insulin secretion in diabetic rats, and has a protective effect on diabetic rats.
Animals ; Blood Glucose ; Diabetes Mellitus, Experimental ; drug therapy ; Glycols ; pharmacology ; Glycoside Hydrolase Inhibitors ; Hypoglycemic Agents ; pharmacology ; Plant Extracts ; chemistry ; Rats ; Tea ; chemistry ; alpha-Glucosidases

OBJECTIVE: To investigate the effect of tea polyphenols on cardiac function in rats with diabetic cardiomyopathy, and the mechanism by which tea polyphenols regulate autophagy in diabetic cardiomyopathy. METHODS: Sixty Sprague-Dawley (SD) rats were randomly divided into six groups: a normal control group (NC), an obesity group (OB), a diabetic cardiomyopathy group (DCM), a tea polyphenol group (TP), an obesity tea polyphenol treatment group (OB-TP), and a diabetic cardiomyopathy tea polyphenol treatment group (DCM-TP). After successful modeling, serum glucose, cholesterol, and triglyceride levels were determined; cardiac structure and function were inspected by ultrasonic cardiography; myocardial pathology was examined by staining with hematoxylin-eosin; transmission electron microscopy was used to observe the morphology and quantity of autophagosomes; and expression levels of autophagy-related proteins LC3-II, SQSTM1/p62, and Beclin-1 were determined by Western blotting. RESULTS: Compared to the NC group, the OB group had normal blood glucose and a high level of blood lipids; both blood glucose and lipids were increased in the DCM group; ultrasonic cardiograms showed that the fraction shortening was reduced in the DCM group. However, these were improved significantly in the DCM-TP group. Hematoxylin-eosin staining showed disordered cardiomyocytes and hypertrophy in the DCM group; however, no differences were found among the remaining groups. Transmission electron microscopy revealed that the numbers of autophagosomes in the DCM and OB-TP groups were obviously increased compared to the NC and OB groups; the number of autophagosomes in the DCM-TP group was reduced. Western blotting showed that the expression of LC3-II/I and Beclin-1 increased obviously, whereas the expression of SQSTM1/p62 was decreased in the DCM and OB-TP groups (P<0.05). CONCLUSIONS Tea polyphenols had an effect on diabetic cardiomyopathy in rat cardiac function and may alter the levels of autophagy to improve glucose and lipid metabolism in diabetes.
Animals ; Autophagy ; drug effects ; Beclin-1 ; analysis ; Blood Glucose ; analysis ; Body Weight ; Diabetic Cardiomyopathies ; drug therapy ; pathology ; physiopathology ; Lipids ; blood ; Male ; Myocardium ; pathology ; Polyphenols ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Tea ; chemistry

BACKGROUND: China has the world's largest tea plantation area in the world. To sustain high yields of the tea, multiple pesticides are used on tea crops to control pests. Organophosphorus (OP) pesticides are among the most widely used types of agricultural pesticides in China. As tea is a significant potential source of exposure to pesticide residues, the public concern has increased in relation to pesticide residues found in tea in China. The aim of the study was to estimate cumulative dietary exposure to OP residues from tea infusion for Chinese tea consumers to determine whether exposure to OP residues from tea infusion is a cause of health concern for tea consumers in China. METHODS: OP residue data were obtained from the China National Monitoring Program on Food Safety (2013-2014), encompassing 1687 tea samples from 12 provinces. Tea consumption data were obtained from the China National Nutrient and Health Survey (2002), comprising 506 tea consumers aged 15-82 years. The transfer rates of residues from tea leaves into tea infusions were obtained from the literature. The relative potency factor (RPF) approach was used to estimate acute cumulative exposure to 20 OP residues from tea infusion using methamidophos as the index compound. Dietary exposure was calculated in a probabilistic way. RESULTS: For tea consumers, the mean and the 99.9th percentile (P99.9) of cumulative dietary exposure to OP residues from tea infusion equalled 0.08 and 1.08 μg/kg bw/d. When compared with the acute reference dose (ARfD), 10 μg/kg bw/d for methamidophos, this accounts for 0.8 and 10.8% of the ARfD. CONCLUSIONS Even when considering OP residues from vegetables, fruits and other foods, there are no health concerns based on acute dietary exposure to OP residues from tea infusion. However, it is necessary to strengthen the management of the OP pesticides used on tea in China to reduce the risk of chronic dietary exposure to OPs from tea infusion.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; China ; Dietary Exposure ; analysis ; Female ; Humans ; Male ; Middle Aged ; Organophosphorus Compounds ; analysis ; Pesticide Residues ; analysis ; Risk Assessment ; methods ; Tea ; chemistry ; Young Adult

Bovine aortic endothelial cells (BAECs) were cultured with high glucose (33 mmol/L), 4 mg/L green tea polyphenols (GTPs) or 4 mg/L GTPs co-treatment with high glucose for 24 h in the presence or absence of Bafilomycin-A1 (BAF). We observed that high glucose increased the accumulation of LC3-II. Treatment with BAF did not further increase the accumulation of LC3-II. Results also showed an increased level of p62 and decreased Beclin-1. However, GTPs showed inversed trends of those proteins. Furthermore, GTPs co-treatment with high glucose decreased the level of LC3-II and a much higher accumulation of LC3-II was observed in the presence of BAF in comparison with high glucose alone. Results also showed a decreased p62 and increased Beclin-1. The results demonstrated that GTPs alleviated autophagy inhibition induced by high glucose, which may be involved in the endothelial protective effects of green tea against hyperglycemia.
Animals ; Autophagy ; drug effects ; Cattle ; Cells, Cultured ; Endothelial Cells ; drug effects ; metabolism ; Gene Expression Regulation ; drug effects ; Glucose ; toxicity ; Macrolides ; pharmacology ; Polyphenols ; chemistry ; pharmacology ; Tea ; chemistry

OBJECTIVETo investigate the protective effects of tea polyphenols (TP) against myocardial ischemia/reperfusion (IR) injuries and explore the possible mechanisms.

METHODSLangendorff-perfused rat hearts were subjected to ischemia for 30 min followed by reperfusion for another 30 min. Myocardial function indices were measured by a left ventricular cannula via a pressure transducer connected to the polygraph in isolated Langendorff hearts and energy metabolism was measured using (31)P nuclear magnetic resonance (NMR) spectroscopy. Whole-cell atch-clamp technique was used to record calcium inward current (I(Ca-L)) in cultured rat cardiac myocytes.

RESULTSCompared with the control hearts, the ex vivo rat hearts with 2.5 mg/L TP treatment showed significantly increased left ventricular developed pressure (LVDP), maximal rise rate of LVDP (+dp/d(tmax)), maximal fall rate of LVDP (-dp/dt(max)), and coronary flow (CF) (P<0.05). During both cardiac ischemia and reperfusion phase, ATP and PCr levels were elevated significantly in TP-treated hearts compared with those in the control hearts (P<0.05). In cultured rat cardiac myocytes, ICa-L was remarkably decreased by TP at the doses of 2.5 and 5.0 mg/L (P<0.01).

CONCLUSIONOur results support a possible protective role of TP against myocardial IR injury by improving myocardial energy metabolism and inhibiting I(Ca-L) in the cardiac myocytes.

Animals ; Calcium ; metabolism ; Calcium Channels ; metabolism ; Cells, Cultured ; Energy Metabolism ; Heart ; drug effects ; In Vitro Techniques ; Myocardial Reperfusion Injury ; Myocardium ; metabolism ; Myocytes, Cardiac ; drug effects ; metabolism ; Polyphenols ; pharmacology ; Rats ; Tea ; chemistry

Tea contains polyphenols and is one of the most popular beverages consumed worldwide. Because most tyrosinase inhibitors that regulate melanogenesis are phenol/catechol derivatives, this study investigated the inhibitory effects of Camellia sinensis water extracts (CSWEs), including black tea, green tea, and white tea extracts, on melanogenesis using immortalized melanocytes. CSWEs inhibited melanin accumulation and melanin synthesis along with tyrosinase activity in a concentration-dependent manner. These inhibitory effects were superior to those of arbutin, a well-known depigmenting agent. The anti-melanogenic activity of black (fermented) tea was higher than that of a predominant tea catecholamine, epigallocatechin gallate. CSWEs, especially black tea extract, decreased tyrosinase protein levels in a concentration-dependent manner. These results suggest that the anti-melanogenic effect of CSWEs is mediated by a decrease in both tyrosinase activity and protein expression, and may be augmented by fermentation. Thus, CSWEs could be useful skin-whitening agents in the cosmetic industry.
Animals ; Catechin/analogs & derivatives/metabolism ; Cell Line ; Melanins/*metabolism ; Melanocytes/enzymology/*metabolism ; Mice ; Monophenol Monooxygenase/*metabolism ; Plant Extracts/*pharmacology ; Plant Leaves/chemistry ; Tea/*chemistry

Fifty male Wistar rats were fed a standard chow diet or a high-fat (HF) diet, and different concentrations of green tea polyphenols (GTPs) (0.8, 1.6, and 3.2 g/L) were administered in the drinking water. We found that the malondialdehyde (MDA) level in the HF diet group was significantly higher than that in the control (CON) group (P<0.05). Decreased peroxisome proliferator-activated receptor (PPAR)-α and sirtuin 3 (SIRT3) expression, and increased manganese superoxide dismutase (MnSOD) acetylation levels were also detected in the HF diet group (P<0.05). GTP treatment upregulated SIRT3 and PPARα expression, increased the pparα mRNA level, reduced the MnSOD acetylation level, and decreased MDA production in rats fed a HF diet (P<0.05). No significant differences in total renal MnSOD and PPAR-γ coactivator-1α (PGC1-α) expression were detected. The reduced oxidative stress detected in kidney tissues after GTP treatment was partly due to the higher SIRT3 expression, which was likely mediated by PPARα.
Acetylation ; drug effects ; Animals ; Antioxidants ; pharmacology ; Diet, High-Fat ; adverse effects ; Gene Expression Regulation, Enzymologic ; drug effects ; Kidney ; drug effects ; metabolism ; Male ; Oxidative Stress ; drug effects ; Polyphenols ; pharmacology ; Rats ; Rats, Wistar ; Reactive Oxygen Species ; metabolism ; Sirtuin 3 ; metabolism ; Tea ; chemistry

OBJECTIVETo study the effect of tea polyphenols (TP) on the apoptosis of germ cells in rats with experimental varicocele.

METHODSThirty-two adolescent male Wistar rats were randomly and equally divided into groups A (sham-operation), B (high-dose TP), C (low-dose TP), and D (experimental left varicocele). Experimental varicocele was induced by partial ligation of the left renal vein in the latter three groups of rats. The animals in groups A and D were fed with normal saline, while those in B and C with TP at 40 and 10 mg per kg per d, respectively, all for 4 weeks. Then, all the rats were sacrificed and the left testes harvested for determination of the expression of HIF-1, Bcl-2, Bax, CytC, and caspase-3 by immunohistochemistry and measurement of the apoptosis index (AI) of spermatogenic cells.

RESULTSThe expression of Bcl-2 was higher in groups B and C than in D but lower than in A (P < 0.05), and lower in C than in B (P < 0.05). However, the expressions of HIF-1, Bax, CytC, and caspase-3 were lower in groups B and C than in D but higher than in A (P < 0.05), and higher in C than in B (P < 0.05). The AI of spermatogenic cells was the lowest in group A, higher in D than in the other groups but lower in B than in C (P < 0.05).

CONCLUSIONTP can reduce the apoptosis of spermatogenic cells in a dose-dependent manner in varicocele rats.

Animals ; Apoptosis ; drug effects ; Caspase 3 ; Cytochromes c ; metabolism ; Dose-Response Relationship, Drug ; Hypoxia-Inducible Factor 1, alpha Subunit ; metabolism ; Ligation ; Male ; Polyphenols ; administration & dosage ; pharmacology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Renal Veins ; Spermatozoa ; drug effects ; Tea ; chemistry ; Testis ; metabolism ; Varicocele ; complications ; metabolism ; bcl-2-Associated X Protein ; metabolism