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1.
Sci Rep ; 6: 20172, 2016 Feb 01.
Article in English | MEDLINE | ID: mdl-26833256

ABSTRACT

Cocoa tea (Camellia ptilophylla) is a naturally decaffeinated tea plant. Previously we found that cocoa tea demonstrated a beneficial effect against high-fat diet induced obesity, hepatic steatosis, and hyperlipidemia in mice. The present study aimed to investigate the anti-adipogenic effect of cocoa tea in vitro using preadipocytes 3T3-L1. Adipogenic differentiation was confirmed by Oil Red O stain, qPCR and Western blot. Our results demonstrated that cocoa tea significantly inhibited triglyceride accumulation in mature adipocytes in a dose-dependent manner. Cocoa tea was shown to suppress the expressions of key adipogenic transcription factors, including peroxisome proliferator-activated receptor gamma (PPAR γ) and CCAAT/enhancer binding protein (C/EBP α). The tea extract was subsequently found to reduce the expressions of adipocyte-specific genes such as sterol regulatory element binding transcription factor 1c (SREBP-1c), fatty acid synthase (FAS), Acetyl-CoA carboxylase (ACC), fatty acid translocase (FAT) and stearoylcoenzyme A desaturase-1 (SCD-1). In addition, JNK, ERK and p38 phosphorylation were inhibited during cocoa tea inhibition of 3T3-L1 adipogenic differentiation. Taken together, this is the first study that demonstrates cocoa tea has the capacity to suppress adipogenesis in pre-adipocyte 3T3-L1 similar to traditional green tea.


Subject(s)
Adipocytes/cytology , Camellia/chemistry , Cell Differentiation/drug effects , Plant Extracts/pharmacology , Water/chemistry , 3T3-L1 Cells , Adipocytes/drug effects , Adipocytes/metabolism , Adipogenesis/drug effects , Animals , Cell Differentiation/genetics , Cell Survival/drug effects , Chromatography, High Pressure Liquid , Gene Expression Regulation/drug effects , Mice , Mitogen-Activated Protein Kinases/metabolism , Phosphorylation/drug effects , Tea , Transcription Factors/metabolism , Triglycerides/metabolism
2.
J Nutr Biochem ; 25(3): 319-28, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24524904

ABSTRACT

Angiogenesis, the process of blood vessel formation, is critical to tumor growth. Ant-angiogenic strategies demonstrated importance in cancer therapy. Cocoa tea (Camellia ptilophylla), a naturally decaffeinated tea commonly consumed as a healthy drink in southern China, had recently been found to be a potential candidate for antiangiogenesis. A novel proanthocyanidin, GC-(4→8)-GCG, which consisted of gallocatechin and gallocatechin 3-O gallate moieties, was discovered and thought to be one of the effective candidates for antiangiogenesis. Hence, the present study aimed to evaluate the antiangiogenesis activities of GC-(4→8)-GCG in vitro and in vivo, and SU5416 was applied as a positive control. The inhibitory effects of GC-(4→8)-GCG on three important processes involved in angiogenesis, i.e., proliferation, migration and differentiation, were examined using human microvascular endothelial cell line HMEC-1 by MTT assay, scratch assay and tube formation assay, respectively. Using transgenic zebrafish embryos TG(fli1:EGFP)y1/+(AB) as an animal model of angiogenesis, the antiangiogenic effect of GC-(4→8)-GCG was further verified in vivo. Our results demonstrated that GC-(4→8)-GCG significantly inhibited migration (P<.001) and tubule formation (P<.001-.05) of HMEC-1 in dose-dependent manner. Regarding intracellular signal transduction, GC-(4→8)-GCG attenuated the phosphorylation of ERK, Akt and p38 dose-dependently in HMEC-1. In zebrafish embryo, the formation of new blood vessels was effectively inhibited by GC-(4→8)-GCG in a dose-dependent manner after 3 days of treatment (P<.001-.05). In conclusion, these results revealed that our novel proanthocyanidin, GC-(4→8)-GCG might be a potential and promising agent of natural resource to be further developed as an antiangiogenic agent.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Cacao/chemistry , Proanthocyanidins/pharmacology , Cell Line , Humans , In Vitro Techniques
3.
Article in English | MEDLINE | ID: mdl-23935682

ABSTRACT

Recent studies suggested that green tea has the potential to protect against diet-induced obesity. The presence of caffeine within green tea has caused limitations. Cocoa tea (Camellia ptilophylla) is a naturally decaffeinated tea plant. To determine whether cocoa tea supplementation results in an improvement in high-fat diet-induced obesity, hyperlipidemia and hepatic steatosis, and whether such effects would be comparable to those of green tea extract, we studied six groups (n = 10) of C57BL/6 mice that were fed with (1) normal chow (N); (2) high-fat diet (21% butterfat + 0.15% cholesterol, wt/wt) (HF); (3) a high-fat diet supplemented with 2% green tea extract (HFLG); (4) a high-fat diet supplemented with 4% green tea extract (HFHG); (5) a high-fat diet supplemented with 2% cocoa tea extract (HFLC); and (6) a high-fat diet supplemented with 4% cocoa tea extract (HFHC). From the results, 2% and 4% dietary cocoa tea supplementation caused a dose-dependent decrease in (a) body weight, (b) fat pad mass, (c) liver weight, (d) total liver lipid, (e) liver triglyceride and cholesterol, and (f) plasma lipids (triglyceride and cholesterol). These data indicate that dietary cocoa tea, being naturally decaffeinated, has a beneficial effect on high-fat diet-induced obesity, hepatomegaly, hepatic steatosis, and elevated plasma lipid levels in mice, which are comparable to green tea. The present findings have provided the proof of concept that dietary cocoa tea might be of therapeutic value and could therefore provide a safer and cost effective option for patients with diet-induced metabolic syndrome.

4.
J Nutr Biochem ; 23(9): 1051-7, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22018604

ABSTRACT

Cocoa tea (Camellia ptilophylla), a naturally decaffeinated tea commonly consumed as a healthy beverage in southern China, has been recently found to be a potential candidate for the treatment of different diseases, including obesity and cancers. The present study aimed to evaluate the anti-liver cancer activities of green cocoa tea infusion (GCTI) in vitro and in vivo using human hepatocarcinoma cell line HepG2 cells and nude mice xenograft model. The apoptotic activities of GCTI were assessed using flow cytometry, Western blotting and immunohistochemical analysis. Our results showed that GCTI significantly inhibited the proliferation of HepG2 cells in a dose-dependent manner (IC50 values=292 µg/ml at 72 h). GCTI induced HepG2 cells to undergo apoptosis, which was demonstrated by cell cycle analysis and annexin-V and propidium iodide staining. The caspase cascade was activated as shown by significant proteolytic cleavage of caspase-3 and PARP in GCTI-treated cells in a dose- and time-dependent manner. In addition, GCTI increased the expression of cell cycle inhibitory proteins (p21, p27 and p53) and the Bax-to-Bcl-2 ratio to induce apoptosis. The antiproliferative effect of GCTI was confirmed in HepG2 xenograft nude mice. The tumor growth was effectively inhibited by GCTI in a dose-dependent manner as indicated by the decrease in tumor volume and tumor weight after 4 weeks of treatment. Administration of GCTI increased terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling and caspase-3-positive cells in the tumor section. In conclusion, these results revealed that GCTI may be a potential and promising agent of natural resource to treat liver cancer.


Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Apoptosis , Camellia/chemistry , Carcinoma, Hepatocellular/diet therapy , Dietary Supplements , Liver Neoplasms/diet therapy , Plant Extracts/therapeutic use , Animals , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/metabolism , Apoptosis Regulatory Proteins/genetics , Apoptosis Regulatory Proteins/metabolism , Carcinoma, Hepatocellular/metabolism , Cell Cycle Checkpoints , Cell Survival , Dietary Supplements/analysis , Female , Gene Expression Regulation, Neoplastic , Hep G2 Cells , Humans , Liver Neoplasms/metabolism , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Plant Extracts/chemistry , Plant Extracts/metabolism , Plant Leaves/chemistry , Random Allocation , Xenograft Model Antitumor Assays
5.
Bioorg Med Chem Lett ; 20(11): 3326-8, 2010 Jun 01.
Article in English | MEDLINE | ID: mdl-20452765

ABSTRACT

Two new metabolites, 3R,5R-Sonnerlactone (1) and 3R,5S-Sonnerlactone (2), were isolated from the mangrove endophytic fungus Zh6-B1 obtained from the South China Sea. Their structures were elucidated by MS and NMR. The absolute configuration of compound 1 was determined by single-crystal X-ray analysis using Cu Kalpha radiation. The absolute configuration of compound 2 was determined by NOESY analysis and comparing circular dichroism spectroscopy with compound 1. The antiproliferative activity of compound 1 and 2 against the multi-drug resistant human oral floor carcinoma cells (KV) was evaluated.


Subject(s)
Fungi/metabolism , Lythraceae/chemistry , Cell Line, Tumor , Circular Dichroism , Crystallography, X-Ray , Humans , Lythraceae/microbiology , Magnetic Resonance Spectroscopy , Mass Spectrometry , Models, Molecular , Seawater , Spectrometry, Mass, Electrospray Ionization
6.
Mol Genet Genomics ; 275(2): 125-35, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16333668

ABSTRACT

Caffeine (1,3,7-trimethylxanthine) and theobromine (3,7-dimethylxanthine) are the major purine alkaloids in plants. To investigate the diversity of N-methyltransferases involved in purine alkaloid biosynthesis, we isolated the genes homologous for caffeine synthase from theobromine-accumulating plants. The predicted amino acid sequences of N-methyltransferases in theobromine-accumulating species in Camellia were more than 80% identical to caffeine synthase in C. sinensis. However, there was a little homology among the N-methyltransferases between Camellia and Theobroma. The recombinant enzymes derived from theobromine-accumulating plants had only 3-N-methyltransferase activity. The accumulation of purine alkaloids was, therefore, dependent on the substrate specificity of N-methyltransferase determined by one amino acid residue in the central part of the protein.


Subject(s)
Alkaloids/biosynthesis , Methyltransferases/metabolism , Alkaloids/chemistry , Amino Acid Sequence , Base Sequence , Cacao/enzymology , Cacao/genetics , Cacao/metabolism , Caffeine/biosynthesis , Camellia/enzymology , Camellia/genetics , Camellia/metabolism , Cloning, Molecular , DNA, Plant/genetics , Gene Library , Genes, Plant , Methyltransferases/chemistry , Methyltransferases/genetics , Molecular Sequence Data , Mutagenesis, Site-Directed , Phylogeny , Plasmids/genetics , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sequence Homology, Amino Acid , Substrate Specificity , Theobromine/biosynthesis
7.
Phytochemistry ; 60(2): 129-34, 2002 May.
Article in English | MEDLINE | ID: mdl-12009315

ABSTRACT

Theacrine (1,3,7,9-tetramethyluric acid) and caffeine were the major purine alkaloids in the leaves of an unusual Chinese tea known as kucha (Camellia assamica var. kucha). Endogenous levels of theacrine and caffeine in expanding buds and young leaves were ca. 2.8 and 0.6-2.7% of the dry wt, respectively, but the concentrations were lower in the mature leaves. Radioactivity from S-adenosyl-L-[methyl-14C]methionine was incorporated into theacrine as well as theobromine and caffeine by leaf disks of kucha, indicating that S-adenosyl-L-methionine acts as the methyl donor not only for caffeine biosynthesis but also for theacrine production. [8-14C]Caffeine was converted to theacrine by kucha leaves with highest incorporation occurring in expanding buds. When [8-14C]adenosine, the most effective purine precursor for caffeine biosynthesis in tea (Camellia sinensis), was incubated with young kucha leaves for 24 h, up to 1% of total radioactivity was recovered in theacrine. However, pulse-chase experiments with [8-14C]adenosine demonstrated much more extensive incorporation of label into caffeine than theacrine, possibly because of dilution of [14C]caffeine produced by the large endogenous caffeine pool. These results indicate that in kucha leaves theacrine is synthesized from caffeine in what is probably a three-step pathway with 1,3,7-methyluric acid acting an intermediate. This is a first demonstration that theacrine is synthesized from adenosine via caffeine.


Subject(s)
Beverages , Camellia/chemistry , Plant Leaves/chemistry , Uric Acid/analogs & derivatives , Uric Acid/metabolism , Adenosine/metabolism , Alkaloids/isolation & purification , Alkaloids/metabolism , Caffeine/metabolism , Carbon Radioisotopes , Methylation , Molecular Structure , Staining and Labeling , Time Factors , Uric Acid/isolation & purification
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