Macrophages from Mice Administered Rhus verniciflua Stokes Extract Show Selective Anti-Inflammatory Activity.

The bark of Rhus verniciflua Stokes (RVS) is used as a food additive and herbal medicine for various inflammatory disorders and cancer in Eastern Asia. RVS has been shown to exert anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated macrophages in vitro, but whether oral administration of RVS affects the inflammatory response of macrophage needs to be verified. RVS was given orally to mice for ten days. For isolation of macrophages, intraperitoneal injection of thioglycollate was performed. For determination of serum inflammatory response, intraperitoneal injection of LPS was applied. RVS stimulated monocyte differentiation in thioglycollate-induced peritonitis by increasing the population of cells expressing CD11b and class A scavenger receptors. These monocyte-derived macrophages showed an increased uptake of acetylated low-density lipoprotein. When peritoneal macrophages from the RVS group were stimulated with LPS, the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in the supernatant decreased, but the level of IL-12 increased. The surface expression of CD86 was reduced, but surface expression of class II major histocompatibility complex molecules was increased. RVS suppressed the serum levels of LPS-induced TNF-α and IL-6. Collectively, RVS promoted monocyte differentiation upon inflammatory insults and conferred selective anti-inflammatory activity without causing overall inhibitory effects on immune cells.

The Anti-Inflammatory Effect of Prunus yedoensis Bark Extract on Adipose Tissue in Diet-Induced Obese Mice.

Chronic, low-grade inflammatory responses occur in obese adipose tissue and play a crucial role in the development of insulin resistance. Macrophages exposed to high glucose upregulate the expression of SRA, a macrophage-specific scavenger receptor. The present study investigated whether Prunus yedoensis (PY) bark extract affects the inflammatory response and scavenger receptor gene expression observed in a diet-induced obesity model in vivo. Oral administration of PY extract significantly reduced fasting blood glucose levels without a change in body weight in mice fed a high fat diet for 17 weeks. PY extract significantly suppressed expression of inflammatory and macrophage genes such as tumor necrosis factor-α, interleukin-6, and F4/80 in epididymal adipose tissue. Among scavenger receptor genes, SRA expression was significantly reduced. The inhibitory responses of PY extract and its fractions were determined through evaluation of scavenger receptor expression in THP-1 cells. PY extract and its ethyl acetate fraction decreased the levels of SRA mRNA and phospho-ERK1/2 during monocyte differentiation. Our data indicate that the anti-inflammatory effects of PY extract and its downregulation of SRA seem to account for its hypoglycemic effects.

Lipid-soluble ginseng extract inhibits invasion and metastasis of B16F10 melanoma cells.

This study was performed to elucidate the effect of a lipid-soluble ginseng extract (LSGE) on cancer invasion and metastasis. The LSGE, even at noncytotoxic concentrations, potently inhibited invasion and migration of B16F10 mouse melanoma cells in a dose-dependent manner. In the presence of 3 µg/mL of LSGE, the invasion and migration of B16F10 cells were significantly inhibited by 98.1% and 71.4%, respectively. Furthermore, the LSGE decreased mRNA and protein levels of matrix metalloproteinase (MMP)-2 in B16F10 cells, leading to a decrease in MMP-2 activity. After B16F10 cells were intravenously injected in the tail vein of C57BL/6 mice, 1000 mg/kg/day of LSGE was orally administered for 13 days, after which lung metastasis of cancer cells was inhibited by 59.3%. These findings indicate that LSGE inhibits cancer cell invasion and migration in vitro and lung metastasis of melanoma cells in vivo by inhibiting MMP-2 expression.

Activation of caspases and inhibition of ribosome biogenesis mediate antitumor activity of Chijongdan in A549 non-small lung cancer cells.

BACKGROUND: Though herbal medicines have been used for cancer prevention and treatment, their scientific evidences still remain unclear so far. Thus, complementary and alternative medicine (CAM) project has been actively executed to reveal the scientific evidences in the USA and other countries. In the present study, we elucidated antitumor mechanism of Chijongdan, an oriental prescription of Rhus verniciflua, processed Panax ginseng, Persicaria tinctoria and Realgar, that has been traditionally applied for cancer treatment in Korea. METHODS: Chijongdan was prepared with extracts of Rhus verniciflua, processed Panax ginseng, Persicaria tinctoria and processed Realgar. The cytotoxicity of Chijongdan was measured by MTT colorimetric assay. Cell cycle analysis was performed by FACS. Western blot was performed to see the apoptosis related proteins. RESULTS: Chijongdan significantly exerted cytotoxicity in A549, H460 and H1299 non-small cell lung carcinoma (NSCLC) cells by MTT assay and also increased the number of ethidium homodimer positively stained cells in A549 NSCLC cells. Also, cell cycle analysis showed that Chijongdan increased sub-G1 population in a concentration dependent manner in A549 cells. In addition, Western blotting revealed that Chijongdan activated cleaved PARP, and caspase 9/3, while attenuated the expression of survival genes such as Bcl-2, Bcl-XL and survivin in A549 cells. Furthermore, Chijongdan suppressed the expression of ribosomal biogenesis related proteins such as upstream binding factor (UBF), Fibrillarin, NPM (B23) and Importin-7 (IPO7) and conversely pan-caspase inhibitor Z--VAD-FMK reversed the apoptotic ability of Chijongdan to cleave PARP and caspase 3 and attenuate the expression of UBF and Fibrillarin in A549 cells. CONCLUSIONS: These findings suggest that Chijongdan induces apoptosis and inhibits ribosomal biogenesis proteins via caspase activation.

Gene expression profiling of KBH-A42, a novel histone deacetylase inhibitor, in human leukemia and bladder cancer cell lines.

The aim of this study was to investigate the anti-tumor activity of KBH-A42, a novel synthetic histone deacetylase (HDAC) inhibitor. KBH-A42 was shown to significantly suppress the proliferation of all 14 human cancer cell lines tested. Among these cell lines, the human leukemia cell line K562 was the most sensitive, whereas the UM-UC-3 bladder cancer cells were the least sensitive. Additionally, in a human tumor xenograft model using Balb/c nude mice, KBH-A42 was shown to significantly inhibit the growth of K562 tumors, although it only slightly inhibited the growth of UM-UC-3 tumors. The results of flow cytometry analysis and caspase 3/7 activation assays showed that the growth inhibition of K562 cells by KBH-A42 was mediated, at least in part, by the induction of apoptosis, but its growth inhibitory effects on UM-UC-3 cells were not mediated by apoptotic induction. In an effort to gain insight into the mechanism by which KBH-A42 inhibits the growth of cancer cells, a microarray analysis was conducted. Four genes were selected from the genes that were down-regulated or up-regulated by KBH-A42 and confirmed via reverse transcription-polymerase chain reaction as follows: Harakiri (HRK), tumor necrosis factor receptor superfamily, member 10b (TNFRSF10B), PYD and CARD domain containing protein gene (PYCARD) and tumor necrosis factor receptor superfamily, member 8 (TNFRSF8). Collectively, the in vitro and in vivo results suggested that KBH-A42 exhibits anti-cancer activity, but various types of cells may be regulated differentially by KBH-A42.

KBH-A42, a histone deacetylase inhibitor, inhibits the growth of doxorubicin-resistant leukemia cells expressing P-glycoprotein.

Multidrug resistance mediated by the drug efflux protein, P-glycoprotein (P-gp), is one of the principal mechanisms by which tumor cells escape the cell death induced by chemotherapeutic agents. In our previous study, we demonstrated that KBH-A42 [N-hydroxy-3-(2-oxo-1-(3-phenylpropyl)-1,2,5,6-tetrahydropyridin-3-yl)propanamide], a synthetic histone deacetylase inhibitor, effectively inhibited the growth of several human cancer cell lines. In this study, we attempted to determine whether KBH-A42 was also capable of inhibiting the growth of multidrug-resistant cells. Doxorubicin dose-dependently inhibited the growth of P-gp-negative K562 human leukemia cells, but did not show substantial inhibition on the growth of P-gp-positive K562/ADR cells even at 10 microM, the highest concentration of KBH-A42 used, which increased the acetylation of histones in these leukemia cells, dose-dependently and effectively inhibited the cell growth, regardless of the presence of P-gp in the cells. KBH-A42 mediated G0/G1 cell cycle arrest, probably as the result of the down-regulation of CDK2, CDK4 and CDK6 and the up-regulation of p21WAF1. When the expression of p21WAF1 was ablated by a specific siRNA, the inhibition of cell growth by KBH-A42 was partly reduced in both cell lines. In addition to the cell cycle arrest, KBH-A42 also induced apoptosis in these cells, which was accompanied by the activation of caspases, including caspase-9, caspase-8 and caspase-3. The pan-caspase inhibitor, Z-VAD-fmk, partially blocked the cell death induced by KBH-A42. These results indicate that KBH-A42 induces cell cycle arrest and apoptosis via the up-regulation of p21WAF1 and caspase activation, respectively, regardless of the presence of P-gp in the leukemia cells.