Enhanced inhibitory effect of ultra-fine granules of red ginseng on LPS-induced cytokine expression in the monocyte-derived macrophage THP-1 cells.

Red ginseng is one of the most popular traditional medicines in Korea because its soluble hot-water extract is known to be very effective on enhancing immunity as well as inhibiting inflammation. Recently, we developed a new technique, called the HAC-gearshift system, which can pulverize red ginseng into the ultra-fine granules ranging from 0.2 to 7.0 microm in size. In this study, the soluble hot-water extract of those ultra-fine granules of red ginseng (URG) was investigated and compared to that of the normal-sized granules of red ginseng (RG). The high pressure liquid chromatographic analyses of the soluble hot-water extracts of both URG and RG revealed that URG had about 2-fold higher amounts of the ginsenosides, the biologically active components in red ginseng, than RG did. Using quantitative RT-PCR, cytokine profiling against the Escherichia coli lipopolysaccharide (LPS) in the monocyte-derived macrophage THP-1 cells demonstrated that the URG-treated cells showed a significant reduction in cytokine expression than the RG-treated ones. Transcription expression of the LPS-induced cytokines such as TNF-alpha, IL-1beta, IL-6, IL-8, IL-10, and TGF-beta was significantly inhibited by URG compared to RG. These results suggest that some biologically active and soluble components in red ginseng can be more effectively extracted from URG than RG by standard hot-water extraction.

Romidepsin (depsipeptide) induced cell cycle arrest, apoptosis and histone hyperacetylation in lung carcinoma cells (A549) are associated with increase in p21 and hypophosphorylated retinoblastoma proteins expression.

Histone deacetylase inhibitor such as romidepsin (depsipeptide, FR901228, FK228) is a promising new class of antineoplastic agent with the capacity to induce growth arrest and/or apoptosis of cancer cells. However, their precise mechanism of action is uncertain. Histone acetylation and deacetylation are involved in transcriptional activation and transcriptional repression, respectively. Romidepsin induced histone hyperacetylation can be correlated with the cell cycle arrest and apoptosis. In the present study, we investigated the effects of romidepsin on cell proliferation, cell cycle arrest, apoptosis and histone hyperacetylation. Expression of Cdc2/Cdk-1, cyclin B1, cyclin A, p21/Cip1, pRb, pRb2/p130, histone H4 and H3 acetylation status were studied with western blot analysis. The induction of apoptosis has been demonstrated by annexin V-FITC binding assay. Extent of apoptosis has been assessed measuring the activity of caspase-3. Romidepsin led to substantial decrease in the expression of Cdc2/Cdk-1, cyclin B1 and phosphorylated pRb and increase in p21. The pRb protein was found to be one of the targets for the romidepsin induced cell cycle arrest. Flow cytometric analysis showed that romidepsin induced cell cycle arrest at G2-M transition, with significant induction of apoptosis at 25 and 50 nM concentration of romidepsin, with an increase in the number of both early and late apoptotic cells. From this study it is concluded that romidepsin inhibit advanced human lung carcinoma (A549) cell proliferation by altering the expression of cell cycle regulators and apoptotic protein.

The effects of quercetin on antioxidant status and tumor markers in the lung and serum of mice treated with benzo(a)pyrene.

Chemoprevention has emerged as a very effective preventive measure against carcinogenesis. Several bioactive compounds present in fruits and vegetables have revealed their cancer curative potential on benzo(a)pyrene (B(a)P) induced carcinogenesis. In the present study, the efficacy of quercetin on the level of lipid peroxides, activities of antioxidant enzymes and tumor marker enzymes in B(a)P induced experimental lung carcinogenesis in Swiss albino mice was assessed. In lung cancer bearing animals there was an increase in lung weight, lipid peroxidation and marker enzymes such as aryl hydrocarbon hydroxylase, gamma glutamyl transpeptidase, 5'-nucleotidase, lactate dehydrogenase and adenosine deaminase with subsequent decrease in body weight and antioxidant enzymes-superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, glutathione reductase, reduced glutathione, vitamin E and vitamin C. Quercetin supplementation (25 mg/kg body weight) attenuated all these alterations, which indicates the anticancer effect that was further confirmed by histopathological analysis. Overall, the above data shows that the anticancer effect of quercetin is more pronounced when used as an chemopreventive agent rather than as a chemotherapeutic agent against B(a)P induced lung carcinogenesis.

Inhibitory effects of histone deacetylase inhibitor depsipeptide on benzo(a)pyrene- and cyclophosphamide-induced genotoxicity in Swiss albino mice.

Depsipeptide (FK228 or FR901228) was evaluated in the mouse bone marrow micronucleus test for its possible protective effect against chromosomal damage induced by benzo(a)pyrene and cyclophosphamide. Three doses of depsipeptide (0.5, 1, and 1.5 mg/kg body weight) were given intravenously to mice for 7 consecutive days prior to administration of genotoxins under investigation. All the three doses of depsipeptide were effective in exerting a protective effect against both benzo(a)pyrene and cyclophosphamide. A significant suppression (34.9% to 67.5%) in the micronuclei formation induced by benzo(a)pyrene and (25.7% to 71.5%) cyclophosphamide was observed following intravenous administration of depsipeptide at doses of 0.5, 1, and 1.5 mg/kg in Swiss albino mice.

Depsipeptide a histone deacetlyase inhibitor down regulates levels of matrix metalloproteinases 2 and 9 mRNA and protein expressions in lung cancer cells (A549).

BACKGROUND: A novel histone deacetylase inhibitor, depsipeptide FR901228 (FK228), is a promising anticancer and antiproliferative agent and has been proposed to regulate gene transcription and reported to lower the risk of several cancers in different cell lines. Depsipeptide showed therapeutic efficacy in Phase I trial of patients with malignant lymphoma. Based on the recognition that basement membrane disruption occurs in acute lung injury and that matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) can degrade type IV collagen, one of the major components of the basement membrane and known to involve in tumor invasion and metastases. We hypothesized that depsipeptide would modulate MMP-2 and MMP-9 production in lung adenocarcinoma cells line (A549). METHODS: In this study, we observed the precise involvement of depsipeptide role on cancer metastasis. A549 cells were treated with depsipeptide at various concentrations (50 and 100nm), for 24h period and then subjected to mRNA levels with RT-PCR and protein levels with Western blot analysis to investigate the impact of depsipeptide on MMP-2 and MMP-9 expressions and further confirmed by using immunocytochemistry. RESULTS: The results showed that depsipeptide treatment decreased the expressions of MMP-2 and MMP-9 in dose-dependent manner. The level of mRNA and proteins expressions were significantly decreased in depsipeptide treated A549 cells in a dose-dependent manner and the level of pro-MMP-9 was found to be high in the 100nm depsipeptide-treated cell lysate of A549 cells, suggesting inhibitory role of depsipeptide on pro-MMP-9 activation. Further immunocytochemistry studies showed the weak expression of MMP-2 and MMP-9 in depsipeptide treated cells. CONCLUSION: We speculate that inhibition of metastasis-specific MMPs in cancer cells may be one of the targets for anticancer function of depsipeptide, and thus provides the molecular basis for the development of depsipeptide as a novel chemopreventive agent for metastatic lung cancer.

Suppression of N-nitrosodiethylamine induced hepatocarcinogenesis by silymarin in rats.

Antioxidants are one of the key players in tumorigenesis, several natural and synthetic antioxidants were shown to have anticancer effects. In the present investigation the efficacy of silymarin on the antioxidant status of N-nitrosodiethylamine (NDEA) induced hepatocarcinogenesis in Wistar albino male rats were assessed. The animals were divided into five groups. The animals in the groups 1 and 3 were normal control and silymarin control, respectively. Groups 2, 4 and 5 were administered with 0.01% NDEA in drinking water for 15 weeks to induce hepatocellular carcinoma (HCC). Starting 1 week prior to NDEA administration group 4 animals were treated with silymarin in diet for 16 weeks, 10 weeks after NDEA administration group 5 animals were treated with silymarin and continued till the end of the experiment period (16 weeks). After the experimental period the body weight, relative liver weight, number of nodules, size of nodules, the levels of lipid peroxidation, glutathione (GSH), and the activities of antioxidant enzymes were assessed in both haemolysate and liver tissue. In group 2 hepatocellular carcinoma induced animals there was an increase in the number of nodules, relative liver weight. The levels of lipid peroxides were elevated with subsequent decrease in the body weight, (glutathione) GSH, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G6PD). In contrast, silymarin + NDEA treated groups 4 and 5 animals showed a significant decrease in the number of nodules with concomitant decrease in the lipid peroxidation status. The levels of GSH and the activities of antioxidant enzymes in both haemolysate and liver were improved when compared with hepatocellular carcinoma induced group 2 animals. The electron microscopy studies were also carried out which supports the chemopreventive action of the silymarin against NDEA administration during liver cancer progression. These findings suggest that silymarin suppresses NDEA induced hepatocarcinogenesis by modulating the antioxidant defense status of the animals.