Green Tea (Camellia sinensis) Extract Induces p53-Mediated Cytotoxicity and Inhibits Migration of Breast Cancer Cells

Camellia annamensis (Theaceae): phytochemical analysis, cytotoxic, antioxidative, and antimicrobial activities

Cytotoxic, antioxidative, and antimicrobial activities of Camellia annamensis, and its chemical compositions were first provided in the current study. Phenolic contents in the methanol extracts of its leaves and flowers were 222.73 ± 0.09 and 64.44 ± 0.08 mg GAE/g extract, whereas flavonoid contents in these parts were 108.80 ± 0.28 and 131.26 ± 0.39 mg rutin/g extract, respectively. By using HPLC-DAD analysis, gallic acid (43.72 ± 0.09 - 81.89 ± 1.83 mg/g) and (-)-epigallocatechin gallate (67.31 ± 1.26 - 70.68 ± 7.82 mg/g) were identified as the major compounds. C. annamensis leaf and flower extracts were moderately cytotoxic against A549, HT-29, SK-Mel-2, MCF-7, HepG2, HeLa, and MKN-7. Particularly, they are better than the standards trolox (IC50 7.57 ± 0.23 µg/mL) in lipid peroxidation inhibitory evaluation, and streptomycin (IC50/MIC = 45.34-50.34/128-256 µg/mL) in antimicrobial assay against the Gram-positive bacteria Enterococcus faecalis ATCC299212, Staphylococcus aureus ATCC25923, and the Gram-negative bacterium Salmonella enterica ATCC13076.

Comparative Anticancer Potential of Green Tea Extract and Epigallocatechin-3-gallate on Breast Cancer Spheroids

Despite advances in diagnosis and therapy, breast cancer remains the leading cause of death in many countries. Green tea (GT) has been proposed to play a crucial role in cancer chemoprevention. Although extensive research has been conducted on GT phytochemicals, most experimental studies concentrate mainly on commercial formulations or isolated catechins. This study presents a comparative investigation into the anticancer properties of green tea extract (GTE) and epigallocatechin-3-gallate (EGCG) in a three-dimensional (3D) MCF-7 breast cancer cell culture. MCF-7 spheroids were exposed to GTE or EGCG, and effects on 3D culture formation, growth, cell viability, and migration were examined. GTE inhibits cell migration and the formation of breast cancer spheroids more effectively than EGCG, while inducing more pronounced morphological changes in the spheroids' structure. These findings suggest that the food matrix improves GTE effects on breast cancer spheroids, supporting the hypothesis that a mixture of phytochemicals might enhance its anticancer potential.

Biological Activities and Polyphenol Content of Qi Cha Tea®, a Functional Beverage of White Tea Containing Botanicals and Dry Botanical Extracts with European Health Claims

Infusions of Camellia sinensis leaves have been known for their health benefits. The Bio Concentrate Assets® (ABC) method is a method of enriching organic infusion leaves (from Camellia sinensis) with organic dry and concentrated extracts using organic acacia gum, and its application to white tea has provided Qi cha tea®. In the present study, the content of tea polyphenols and caffeine, and the biochemical properties of Qi cha tea® and its botanical constituents (elderberry, tulsi, Echinacea purpurea, orange peel, lemongrass, and acacia gum) were assessed. Antioxidant and cell viability activities were determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and MTT (3-(4, 5-dimethyl thiazol-2-yl)-2, 5-diphenyl tetrazolium bromide) assay in human Caco-2 and HCT-116 cell lines, and ascorbic acid and tamoxifen, respectively. The caffeine and polyphenol composition of Qi cha tea® was modified with less caffeine and gallic acid and more epigallocatechin gallate (EGCG) than the original white tea. The majority of the tested botanical samples including Qi cha tea® at 50 µg/mL show similar antioxidant activities, with the exception of Echinacea purpurea. The greatest effect was found for white tea. The antioxidant power of the Qi cha tea® (90% at 50 µg/mL for pressurized liquid extraction (PLE) was divided by approximately a factor of two (61% at 50 µg/mL for pressurized liquid extraction products (PLEP)), which corresponds to the 48.3% (mass/mass) white tea original content in the Qi cha tea®. Qi cha tea® shows the lowest cytotoxic activity in the viability of the two cell lines when compared to white tea. The application of the ABC method to Qi cha tea® using various botanicals and dry extract with acacia gum as blinder has allowed the development of a new innovative functional health beverage that complies with European health claims.

Effects of green tea extract treatment on erythropoiesis and iron parameters in iron-overloaded β-thalassemic mice

β-Thalassemia is characterized by ineffective erythropoiesis leading to chronic anemia. Thus, increased iron absorption from the duodenum and via blood transfusions is required to maintain normal blood hemoglobin (Hb) levels and iron chelators in the removal of excessive iron. Certain agents are also needed for the improvement of stress erythropoiesis and iron dysregulation. Green tea extract (GTE), which is rich in epigallocatechin-3-gallate (EGCG), is known to possess radical scavenging and iron-chelating activities. We aimed to assess the effects of green tea extract on erythroid regulators, iron mobilization and anti-lipid peroxidation in the liver, spleen, and kidneys of iron-loaded β-globin gene knockout thalassemic (BKO) mice. Our results indicate that treatments of green tea extract and/or deferiprone (DFP) diminished levels of plasma erythropoietin (EPO) and erythroferrone (ERFE), and consistently suppressed kidney Epo and spleen Erfe mRNA expressions (p < .05) in iron- loaded BKO mice when compared with untreated mice. Coincidently, the treatments decreased plasma ferritin (Ft) levels, iron content levels in the liver (p < .05), spleen (p < .05), and kidney tissues of iron-loaded BKO mice. Furthermore, lipid-peroxidation products in the tissues and plasma were also decreased when compared with untreated mice. This is the first evidence of the orchestral role of green tea extract abundant with epigallocatechin-3-gallate in improving ineffective erythropoiesis, iron dysregulation and oxidative stress in iron-overloaded β-thalassemic mice.

Extracts of Common Vegetables Inhibit the Growth of Ovary Cancer Cells

There is recent interest in a diet that can be recommended for patients suffering from cancer. In this respect, the effects were studied of the extracts of several common fruits, herbs and vegetables on the viability of two human ovary cancer cell lines (SKOV-3 and PEO1) in vitro. Normal human MRC-5 fibroblasts were used as a control cell line. The extracts of garlic, horseradish and curly kale as well as green and black tea were the most effective in lowering the viability of ovarian cancer cells, while not affecting the viability of MRC-5 fibroblasts. Except for garlic and horseradish, the cytotoxic effects of the extracts correlated with their polyphenol content. The examination of changes in the content of ATP and glutathione, in the level of reactive oxygen species, mitochondrial potential and mitochondrial mass did not show a consistent pattern, suggesting that various extracts may act via different mechanisms. Although the extracts’ toxicity to cells in vitro is a first and direct suggestion concerning their possible anticancer effects in vivo, these results point to potential vegetable candidates to become diet components recommended for ovary cancer patients.

Green Tea Epigallocatechin-3-Gallate Regulates Autophagy in Male and Female Reproductive Cancer

With a rich abundance of natural polyphenols, green tea has become one of the most popular and healthiest nonalcoholic beverages being consumed worldwide. Epigallocatechin-3-gallate (EGCG) is the predominant catechin found in green tea, which has been shown to promote numerous health benefits, including metabolic regulation, antioxidant, anti-inflammatory, and anticancer. Clinical studies have also shown the inhibitory effects of EGCG on cancers of the male and female reproductive system, including ovarian, cervical, endometrial, breast, testicular, and prostate cancers. Autophagy is a natural, self-degradation process that serves important functions in both tumor suppression and tumor cell survival. Naturally derived products have the potential to be an effective and safe alternative in balancing autophagy and maintaining homeostasis during tumor development. Although EGCG has been shown to play a critical role in the suppression of multiple cancers, its role as autophagy modulator in cancers of the male and female reproductive system remains to be fully discussed. Herein, we aim to provide an overview of the current knowledge of EGCG in targeting autophagy and its related signaling mechanism in reproductive cancers. Effects of EGCG on regulating autophagy toward reproductive cancers as a single therapy or cotreatment with other chemotherapies will be reviewed and compared. Additionally, the underlying mechanisms and crosstalk of EGCG between autophagy and other cellular processes, such as reactive oxidative stress, ER stress, angiogenesis, and apoptosis, will be summarized. The present review will help to shed light on the significance of green tea as a potential therapeutic treatment for reproductive cancers through regulating autophagy.