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  • Mechanisms of Apoptotic Effects Induced by Resveratrol, Dibenzoylmethane, and Their Analogues on Human Lung Carcinoma Cells

Chia-Jui Weng, Ya-Ting Yang, Chi-Tang Ho and Gow-Chin Yen

J. Agric. Food Chem., Article ASAP

Abstract

While lung cancer accounts for approximately 20% of cancer diagnoses, it is the leading cause of tumor-related deaths. The apoptotic effects of 3,5,4′-trihydroxystilbene (resveratrol), dibenzoylmethane (DBM), and their analogues on human lung cancer cells are generally unclear. The aims of this study were to evaluate the apoptotic effects and molecular mechanisms of resveratrol, DBM, and their analogues on human lung cancer cells.

The results of the MTT and lactate dehydrogenase (LDH) leakage assays indicated that resveratrol, 3,5,4′-trimethoxy-trans-stilbene (MR-3), and 1-(2-hydroxy-5-methylphenyl)-3-phenyl-1,3-propanedione (HMDB) could inhibit cell population growth and induce cell injury in A549 and CH27 cell lines. Resveratrol and HMDB could induce apoptotic cell death in the A549 and CH27 cell lines. Moreover, cellular growth of the A549 and CH27 cell lines might be inhibited by MR-3 through induction of apoptosis and regulation of the cell cycle. The A549 and CH27 cell lines treated with resveratrol, MR-3, and HMDB showed a time-dependent reduction of mitochondrial membrane potential, and the Bax/Bcl-2 ratio increased gradually with a higher concentration of polyphenols.

The resveratrol-, MR-3-, and HMDB-induced apoptosis in the  A549 and CH27 cell lines were controlled through activation of caspase-9 and caspase-3 and subsequent cleavage of PARP. In conclusion, we have demonstrated that resveratrol, DBM, and their analogues could be effective candidates for chemoprevention of lung cancer and HMDB might have the strongest ability for inducing apoptosis.

  • Effects of Tea Catechins, Epigallocatechin, Gallocatechin, and Gallocatechin Gallate, on Bone Metabolism

Chun Hay Ko, Kit Man Lau, Wing Yee Choy and Ping Chung Leung Institute of Chinese Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, SAR, People’s Republic of China

J. Agric. Food Chem., Article ASAP Publication Date (Web): August 4, 2009

Abstract

In this study, three tea catechins, epigallocatechin (EGC), gallocatechin (GC), and gallocatechin gallate (GCG), were investigated for their effects on bone metabolism. The effects of the tea catechins on bone formation were evaluated using cultured rat osteoblast-like osteosarcoma cell line UMR-106. EGC stimulated alkaline phosphatase activity significantly at concentrations of 10 and 20 µM. The amount of mineralization also increased significantly with EGC. On another cell culture platform, EGC significantly inhibited osteoclast formations from RAW 264.7 cells upon receptor activation of nuclear factor-?B ligand induction on the fourth day of treatment, at a concentration of 10 µM. EGC also dose-dependently inhibited the mRNA expression of tatrate-resistant acid phosphatase. GC and GCG could decrease osteoclastogenesis at 20 µM. The present study illustrated that the tea catechins, EGC in particular, had positive effects on bone metabolism through a double process of promoting osteoblastic activity and inhibiting osteoclast differentiations.

  • Terpenoid Constituents of Abies chensiensis with Potential Anti-inflammatory Activity

Yong-Li Li, Xian-Wen Yang, Su-Mei Li, Yun-Heng Shen, Hua-WuZeng, Xiao-Hua Liu, Jian Tang and Wei-Dong Zhang

J. Nat. Prod., Article ASAP May 12, 2009

Abstract

Six new triterpenes (neoabieslactones A-F, 1-6) and 17 known compounds were isolated from the aerial parts of Abies chensiensis. The structures of the new triterpenes were proposedby 1D and 2D NMR spectroscopy. Compound 1 was confirmed structurally by X-ray crystallography. In a bioassay against LPS-induced NO production in RAW264.7 macrophages, three compounds, neoabieslactone E (5),(12R,13R)-8,12-epoxy-14-labden-13-ol (7), and manool (8), exhibited IC50 values of 9.1, 1.9, and 9.6 µg/mL, respectively.

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