White tea (Camellia sinensis) inhibits proliferation of the colon cancer cell line, HT-29, activates caspases and protects DNA of normal cells against oxidative damage

Tea (Camellia sinensis) is one of the most consumed beverages in the world. White tea is made from the buds and young leaves of the tea plant which are steamed and dried, whilst undergoing minimal oxidation. The MTT assay was used to test the extract on the effect of the proliferation of the colorectal cancer cell line, HT-29. The extract inhibited the proliferation of HT-29 cells with an IC50 of 87 mu g/ml. The extract increased the levels of caspase-3, -8, and -9 activity in the cells. DNA damage in 3T3-L1 normal cells was detected by using the comet assay. The extract protected 3T3-L1 cells against H2O2-induced DNA damage. The results from this study show that white tea has antioxidant and antiproliferative effects against cancer cells, but protect normal cells against DNA damage. Regular intake of white tea can help to maintain good health and protect the body against disease. (C) 2014 The Authors. Published by Elsevier Ltd

Evaluation of cytotoxic, DNA protecting and LPS induced MMP-9 down regulation activities of Plectranthus amboinicus (Lour) Spreng. essential oil.

Introduction: Plectranthus amboinicus(Lour) Spreng is a known medicinal plant used in Siddha and Ayurveda medicines in India. It has enormous medicinal potential to treat various diseases. Methods: The present study focused on the use of essential oil obtained from the leaves of Plectranthus amboinicus to test cytotoxicity against breast (MCF-7) and colorectal (HT-29) cancer cell lines, to protect DNA from H2O2 induced genotoxicity through comet assay and to treat inflammation in lipopolysaccharide (LPS) induced over expression of matrix metalloproteinase-9 (MMP-9) in human peripheral blood mononuclear cells (PBMCs) by gelatin zymogram and inhibition at transcriptional level confirmed using RT-PCR (reverse transcriptase polymerase chain reaction). Results: Cytotoxicity of essential oil against MCF-7 and HT-29 cancer cell lines revealed the IC50 values of 53±0.01 and 87±0.01μg/mL respectively. At 200μg/mL essential oil protected against 75% of DNA damage in 3T3-L1 fibroblast cells. Essential oil showed significant reduction in production of MMP-9 in a concentration dependent manner. Conclusion: Overall, the results showed that essential oil of P. amboinicus is a potent bioactive substance and it could be used in herbal medicine preparations

Decrease of CD69 levels on TCR Vα7.2+CD4+ innate-like lymphocytes is associated with impaired cytotoxic functions in chronic hepatitis B virus-infected patients

Hepatitis B virus (HBV) infection is a major cause of chronic liver disease that may progress to liver cirrhosis and hepatocellular carcinoma. Host immune responses represent the key determinants of HBV clearance or persistence. Here, we investigated the role of the early activation marker, CD69 and effector cytokines, granzyme B (GrB) and IFN-γ in the exhaustion of innate-like TCR Vα7.2+CD4+T cells, in 15 individuals with chronic HBV (CHB) infection where six were HBV DNA+ and nine were HBV DNA-. The percentage of cytokine-producing T cells and MAIT cells were significantly perturbed in HBV patients relative to healthy controls (HCs). The intracellular expression of GrB and IFN-γ was significantly reduced in MAIT cells derived from HBV-infected patients as compared to HCs, and the levels correlated with the percentage and levels [mean fluorescence intensity (MFI)] of CD69 expression. The total expression of CD69 (iMFI) was lower in CHB patients as compared to HCs. The frequency of CD69+ cells correlated with the levels of cytokine expression (MFI), particularly in CHB patients as compared to HCs. In summary, the polyfunctionality of peripheral T cells was significantly reduced among CHB patients, especially in the TCR Vα7.2+CD4+T cells, and the levels of cytokine expression correlated with functional cytokine levels