Min-Ho Han

Induction of Apoptosis by Ethanol Extracts of Ganoderma lucidum in Human Gastric Carcinoma Cells

Ganoderma lucidum, a well-known medicinal mushroom, is highly valued and commonly used in Oriental medicine. Although recent experimental data has revealed the proapoptotic potency of G. lucidum extracts, the underlying mechanisms of this apoptotic activity have not yet been studied in detail. In the present study, the effects of ethanol extracts of G. lucidum (EGL) on the growth of an AGS human gastric carcinoma cell line were investigated. We found that EGL treatment resulted in a dose and time-dependent significant decrease in the viability of AGS cells. This decreased viability was caused by apoptotic cell death, with observed chromatin condensation and an accumulation of apoptotic fraction. EGL treatment induced the expression of death receptor-related proteins such as death receptor 5 and tumor necrosis factor-related apoptosis-inducing ligand, which further triggered the activation of caspase-8 and the cleavage of Bid. In addition, the increase in apoptosis that was induced by EGL was correlated with activation of caspase-9 and -3, downregulation of IAP family proteins such as XIAP and survivin, and concomitant degradation of poly (ADP-ribose) polymerase. Moreover the activity of Akt was downregulated in EGL-treated cells, and the phosphatidylinositol-3 kinase/ Akt inhibitor LY294002 sensitized the cells to EGL-induced apoptosis. The results indicated that EGL induces the apoptosis of AGS cells through a signaling cascade of death receptor-mediated extrinsic, as well as mitochondria-mediated intrinsic, caspase pathways which are associated with inactivation of the Akt signal pathway.

Inhibition of Adipocyte Differentiation and Adipogenesis by Aged Black Garlic Extracts in 3T3-L1 Preadipocytes

Garlic (Allium sativum) has been used as a source food as well as a traditional folk medicine ingredient since ancient times. Aged black garlic is a type of fermented garlic and is expected to have stronger anticancer and antioxidant activities than raw garlic. However, the mechanisms of their inhibitory effects on adipocyte differentiation and adipogenesis are poorly understood. In the present study, the effects and mechanisms of water extracts of raw garlic (WERG) and aged black garlic (WEABG) on adipocyte differentiation and adipogenesis in 3T3-L1 preadipocytes were investigated. Treatment with WEABG significantly suppressed terminal differentiation of 3T3-L1 preadipocytes in a dose-dependent manner as confirmed by a decrease in lipid droplet number and lipid content through Oil Red O staining, however WERG had no such effect. In addition, WEABG reduced accumulation of cellular triglyceride, which is associated with a significant inhibition of key pro-adipogenic transcription factors including peroxisome proliferator-activated receptor (PPAR), cytidine-cytidine-adenosine-adenosine-thymidine (CCAAT)/enhancer binding proteins (C/EBP) and C/EBP. Taken together, these results provide important new insight that aged black garlic might inhibit adipogenesis by suppressing the pro-adipogenic transcription factors in 3T3-L1 preadipocytes, and further studies will be needed to identify the active compounds that confer the anti-obesity activity of aged black garlic.

Anti-inflammatory Effects of Schisandra chinensis (Turcz.) Baill Fruit Through the Inactivation of Nuclear Factor-κB and Mitogen-activated Protein Kinases Signaling Pathways in Lipopolysaccharide-stimulated Murine Macrophages

Background: Schisandrae Fructus, the dried fruit of Schisandra chinensis (Turcz.) Baill. (Magnoliaceae), is widely used in traditional medicine for the treatment of a number of chronic inflammatory diseases. This study examined the anti-inflammatory effects of Schisandrae Fructus ethanol extract (SF) on the production of pro-inflammatory substances in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Methods: To measure the effects of SF on pro-inflammatory mediator and inflammatory cytokine’s expression and production in RAW 264.7 cells, we used the following methods: cell viability assay, Griess reagent assay, enzyme-linked immunosorbent assay, reverse transcriptase-polymerase chain reaction, Western blotting analysis and immunofluorescence staining. Results: Stimulation of the RAW 264.7 cells with LPS caused an elevated production of nitric oxide (NO), tumor necrosis factor α (TNF-α) and interleukin (IL)-1β, which was markedly inhibited by the pretreatment with SF without causing any cytotoxic effects. SF also inhibited the expression of inducible NO synthase, TNF-α, and IL-1β protein and their mRNAs in LPS-stimulated RAW 264.7 cells. Furthermore, SF attenuated LPS-induced nuclear translocation of nuclear factor-κB (NF-κB) by reducing inhibitory-κB degradation, and reduced the phosphorylation of mitogen-activated protein kinases (MAPKs), implying that SF regulated LPS-induced NF-κB-dependent inflammatory pathways through suppression of MAPKs activation. Conclusions: SF may be useful for the treatment of various inflammatory diseases.

Baicalein Induces Caspase-dependent Apoptosis Associated with the Generation of ROS and the Activation of AMPK in Human Lung Carcinoma A549 Cells.

Preclinical Research

Polyphenols from Korean prostrate spurge Euphorbia supina induce apoptosis through the Fas-associated extrinsic pathwayand activation of ERK in human leukemic U937 cells

The Korean prostrate spurge Euphorbia supina (Euphorbiaceae family) has been used as a folk medicine in Korea against a variety of ailments such as bronchitis, hemorrhage, jaundice and multiple gastrointestinal diseases. Polyphenols from Korean E. supina (PES) which include quercetin and kaempferol derivatives have anticancer properties. Hence, we investigated the anticancer effects of PES on U937 human leukemic cells. Firstly, PES significantly inhibited the proliferation of U937 cells in a dose-dependent manner. PES induced accumulation of the sub-G1 DNA content (apoptotic cell population), apoptotic bodies and chromatin condensation and DNA fragmentation in the U937 cells. PES also induced activation of caspase-3, -8 and -9, subsequent cleavage of PARP, and significantly suppressed XIAP, cIAP-1 and cIAP-2 in dose-dependent manner. Furthermore, PES activated Bid, and induced the loss of mitochondrial membrane potential (MMP, ΔΨm) along with upregulation of pro-apoptotic proteins (Bax and Bad), and downregulation of anti-apoptotic proteins (Bcl-2 and Bcl-xL) and cytochrome c release. The Fas receptor was upregulated by PES in a dose-dependent manner, suggesting that the extrinsic pathway was also involved in the PES-induced apoptosis. Moreover, the PES-induced apoptosis was at least in part associated with extracellular signal-regulated kinase (ERK) activation in the U937 human leukemic cells. This study provides evidence that PES may be useful in the treatment of leukemia.

Lonicera japonica Thunb. Induces caspase-dependent apoptosis through death receptors and suppression of AKT in U937 human leukemic cells

Decoctions obtained from the dried flowers of Lonicera japonica Thunb. (Indongcho) have been utilized in folk remedies against inflammatory diseases. Recently, many agents that have used for inflammatory diseases are showing anticancer effects. Here, we have isolated polyphenols extracted from lyophilized Lonicera japonica Thunb (PELJ) and investigated the anticancer effects of PELJ on U937 cells. Here, we demonstrated that PELJ induced apoptosis by upregulation of DR4 and Fas, and further it is augmented by suppression of XIAP. In addition, The PELJ‐induced apoptosis is at least in part by blocking PI3K/Akt pathway. These findings suggest that PELJ may provide evidence of anticancer activities on U937 cells. Further study for detailed mechanism and the effects on animal models is warranted to determine whether PELJ provide more conclusive evidence that PELJ which may provide a beneficial effect for treating cancer.

Effects of Sodium Butyrate, a Histone Deacetylase Inhibitor, on TRAIL-mediated Apoptosis in Human Bladder Cancer Cells

Anti-Aging Research Center and Blue-Bio Industry RIC, Dongeui U niversity, Busan 614-71, KoreaReceived October 26, 2015/Revised November 12, 2015/Accepted November 13, 2015The tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is considered a promising anticancer agent due to its unique ability to induce cancer cell death having only negligible effects on normal cells. However, many cancer cells tend to be resistant to TRAIL. In this study, we inves-tigated the effects and molecular mechanisms of sodium butyrate (SB), a histone deacetylase inhibitor, in sensitizing TRAIL-induced apoptosis in 5637 human bladder cancer cells. Our results indicated that co-treatment with SB and TRAIL significantly increased the apoptosis induction, compared with treat-ment with either agent alone. Co-treatment with SB and TRAIL effectively increased the cell-surface expression of death receptor (DR) 5, but not DR4, which was associated with the inhibition of cellular Fas-associated death domain (FADD)-like interleukin-1β-converting enzyme (FLICE) inhibitory protein (c-FLIP). Furthermore, the activation of caspases (caspase-3, -8 and -9) and degradation of poly(ADP- ribose) were markedly increased in 5637 cells co-treated with SB and TRAIL; however, the synergistic effect was perfectly attenuated by caspase inhibitors. We also found that combined treatment with SB and TRAIL effectively induced the expression of pro-apoptotic Bax, cytosolic cytochrome c and cleave Bid to truncated Bid (tBid), along with down-regulation of anti-apoptotic Bcl-xL expression. These re-sults collectively suggest that a combined regimen of SB plus TRAIL may offer an effective therapeutic strategy for safely and selectively treating TRAIL-resistant bladder cancer cells.Keywords :

Ethanol Extract of Schisandra chinensis (Turcz.) Baill. Reduces AICAR-induced Muscle Atrophy in C2C12 Myotubes

Young-Soon Kang 1 , Cheol Park 2 , Min-Ho Han 1 , Su-Hyun Hong 1 , Hye-Jin Hwang 3,4 , Byung Woo Kim 3,5 , Cheol Min Kim and Yung Hyun Choi* Department of Biochemistry, Dongeui University College of Korean Medicine, Busan 614-052, Korea 2 Department of Molecular Biology, College of Natural Sciences & Human Ecology, Dongeui University, Busan 614-714, Korea Anti-Aging Research Center & Blue-Bio Industry RIC, Dongeui University, Busan 614-714, Korea Department of Food and Nutrition, College of Natural Sciences & Human Ecology, Dongeui University, Busan 614-714, Korea 5 Department of Life Science and Biotechnology, College of Natural Sciences & Human Ecology, Dongeui University, Busan 614-714, Korea Department of Biochemistry, Busan National University College of Medicine, Yangsan 626-870, KoreaMuscle atrophy, known as a sarcopenia, is defined as a loss of muscle mass resulting from a reduction in the muscle fiber area or density due to a decrease in muscle protein synthesis and an increase in protein breakdown. Schisandrae fructus (SF) extract of the fruits of Schisandra chinensis (Turcz) Baillon has been used as a tonic in traditional medicine for thousands of years. Although a great deal of work has been carried out on the therapeutic potential of SF, its pharmacological mechanisms of action in muscle diseases actions remain unclear. In the present study, we investigated the inhibitory effects of SF ethanol extracts on the production of muscle atrophy factors in C2C12 myotubes stimulated with 5-aminoimidazole-4-carboxamide-ribonucleotide (AICAR), an AMP-activated kinase (AMPK) activator, and sought to determine the underlying mechanisms of action. AICAR upregulated atrophy-related ubiquitin ligase muscle RING finger-1 (MuRF-1) and stimulated the levels of the forkhead box O3a (FoxO3a) transcription factor in the C2C12 myotubes. SF supplementation effectively and concentration-dependently counteracted AICAR-induced muscle cell atrophy and reversed the increased expression of MuRF-1 and FoxO3a. Our study demonstrates that SF can reverse the muscle cell atrophy caused by AICAR through regulation of the AMPK and FoxO3a signaling pathways, followed by inhibition of MuRF-1.