Jong-Suk Lee

The anti-angiogenic effects of 1-furan-2-yl-3-pyridin-2-yl-propenone are mediated through the suppression of both VEGF production and VEGF-induced signaling

Angiogenesis plays a critical role in the pathogenesis of malignant tumor growth and metastases. Since cyclooxygenase (COX)-2 expression is positively correlated with vascular endothelial growth factor (VEGF) expression and enhanced angiogenesis, COX-2 inhibitors have been focused on as angiogenesis-inhibiting drugs that may offer a complementary modality to classical strategies for cancer therapy. In this study, we evaluated the potential antiangiogenic effects of 1-furan-2-yl-3-pyridin-2-yl-propenone (FPP-3), a dual COX/5-LOX inhibitor. In HT1080 cancer cells, FPP-3 significantly suppressed release of VEGF as well as activation of NF-kappaB, a transcriptional factor required for VEGF expression. In a chick chorioallantoic membrane (CAM) assay, FPP-3 dose-dependently suppressed VEGF- and MCF-7 human breast cancer cell-induced angiogenesis. In experiments with human umbilical vein endothelial cells (HUVECs), FPP-3 dose-dependently decreased not only the cell survival and proliferation but also the tube formation and invasion using Matrigel-coated plates. Such antiangiogenic activity correlated with suppression of VEGF-induced matrix metalloproteinase (MMP)-2 expression, reactive oxygen species (ROS) production, and extracellularly regulated kinase (ERK) phosphorylation. Furthermore, in contrast to the case of NS398, a selective COX-2 inhibitor, FPP-3 did not alter the ratio of tissue factor (TF)/tissue factor pathway inhibitor (TFPI) expression, a coagulation index. These results indicate that FPP-3 could be used as an effective antiangiogenic agent without the risk of developing thrombotic complications.

Grifola frondosa (maitake mushroom) water extract inhibits vascular endothelial growth factor-induced angiogenesis through inhibition of reactive oxygen species and extracellular signal-regulated kinase phosphorylation.

Grifola frondosa, a large edible mushroom also known as maitake, has been used as a health food for centuries in China and Japan. In the present study, we examined anti-angiogenic activity of a water extract of the fruiting body of G. frondosa (GFW). An in vivo angiogenesis assay using chick chorioallantoic membrane revealed that GFW (1-100 microg/mL) dose-dependently inhibited vascular endothelial growth factor (VEGF)-induced angiogenesis. In addition, GFW inhibited VEGF-induced proliferation, chemotactic migration, and capillary-like tube formation of human umbilical vein endothelial cells (HUVECs) in a concentration-dependent manner. Upon stimulation by VEGF, HUVECs rapidly increased reactive oxygen species production, which was significantly blocked by the treatment with GFW. Moreover, phosphorylation of extracellular signal-regulated kinase 1/2, a downstream signaling molecule following VEGF receptor activation, was also inhibited by GFW. The results indicate that GFW effectively inhibit angiogenesis by blocking VEGF signaling and suggest that G. frondosa fruiting body may be a valuable medicinal food for treatment of angiogenesis-associated human diseases.

The anti-angiogenic and anti-tumor activity of synthetic phenylpropenone derivatives is mediated through the inhibition of receptor tyrosine kinases.

Abnormal angiogenesis plays a critical role in the pathogenesis of various diseases such as cancer and chronic inflammation. A variety of pro-angiogenic factors, including vascular endothelial growth factor (VEGF), exert their action through endothelial receptor tyrosine kinases (RTKs). The synthetic phenylpropenone derivatives, used in this study were the following: 1,3-diphenyl-propenone (DPhP), 3-phenyl-1-thiophen-2-yl-propenone (PhT2P), 3-phenyl-1-thiophen-3-yl-propenone (PhT3P) and 1-furan-2-yl-3-phenyl-propenone (FPhP). These derivatives were screened for their inhibitory effect on VEGF-induced angiogenesis in vitro using HUVECs and in vivo using chick chorioallantoic membrane (CAM). The order of anti-angiogenic activity was DPhP>FPhP>PhT3P>PhT2P. The most effective compound DPhP, also known as chalcone, showed weak VEGF receptor tyrosine kinase activity compared with the specific inhibitor, SU4312 (3-[[4-(dimethylamino)phenyl]methylene]-1,3-dihydro-2H-indol-2-one). However, DPhP also inhibited several other receptor tyrosine kinases including Tie-2, epithermal growth factor (EGF) receptor, EphB2, fibroblast growth factor (FGF) receptor 3 and insulin-like growth factor-1 (IGF-1) receptor, as revealed by a receptor tyrosine kinase array assay. In addition, the down-stream signaling, including ERK phosphorylation and NF-κB activation, after receptor activation was significantly inhibited by DPhP. Furthermore, in the HT29 human colon cancer cell-inoculated CAM assay, the tumor growth and tumor-induced angiogenesis was significantly inhibited by DPhP (10μg/ml). These results suggest that the simple flavonoid, DPhP (chalcone), has valuable potential as an antiangiogenic and anti-cancer agent, and its action is mediated through the inhibition of multi-target RTKs including VEGF receptor 2.

Immunochromatographic strip assay for the rapid and sensitive detection of Salmonella Typhimurium in artificially contaminated tomato samples.

This study was designed to confirm the applicability of a liposome-based immunochromatographic assay for the rapid detection of Salmonella enterica subsp. enterica serovar Typhimurium (Salmonella Typhimurium) in artificially contaminated tomato samples. To determine the detection limit and pre-enrichment incubation time (10, 12, and 18 h pre-enrichment in 1% buffered peptone water), the tests were performed with different cell numbers of Salmonella Typhimurium (3 × 10(0), 3 × 10(1), 3 × 10(2), and 3 × 10(3) CFU·mL(-1)) inoculated into 25 g of crushed tomato samples. The assay was able to detect as few as 30 Salmonella Typhimurium cells per 25 g of tomato samples (1.2 cells·g(-1)) after 12 h pre-enrichment incubation. Moreover, when the developed assay was compared with traditional morphological and biochemical culture-based methods as well as colloidal gold nanoparticle-based commercial test strips, the developed assay yielded positive results for the detection of Salmonella Typhimurium within a shorter period time. These findings confirm that the developed assay may have practical application for the sensitive detection of Salmonella Typhimurium in various food samples, including raw vegetables, with a relatively low detection limit and shorter analysis time.

Effect of roll speed ratio on deformation characteristics of IF steel subjected to differential speed rolling

The paper investigates the effect of the roll speed ratio on the deformation characteristics of interstitial free (IF) steel processed by the differential speed rolling (DSR) technique. An intense plastic strain induced by a single DSR with various roll speed ratios ranging from 1:1 to 1:4 for the lower and upper rolls was successfully imparted to the samples, resulting in the formation of fine elongated ferrite grains as the roll speed ratio increased. Observations of the preferred orientation using electron back-scattered diffraction and transmission electron microscopy revealed that the {110} slip was readily activated as the dominant deformation mode in order to accommodate the intense plastic strain imposed by the DSR. In addition, the microhardness values of the IF steel sample deformed via DSR under a roll speed ratio of 1:4 increased, and this is discussed on basis of the frictional force between the roll and the sample during DSR deformation.

Manganese (II) induces chemical hypoxia by inhibiting HIF-prolyl hydroxylase: implication in manganese-induced pulmonary inflammation.

Manganese (II), a transition metal, causes pulmonary inflammation upon environmental or occupational inhalation in excess. We investigated a potential molecular mechanism underlying manganese-induced pulmonary inflammation. Manganese (II) delayed HIF-1alpha protein disappearance, which occurred by inhibiting HIF-prolyl hydroxylase (HPH), the key enzyme for HIF-1alpha hydroxylation and subsequent von Hippel-Lindau(VHL)-dependent HIF-1alpha degradation. HPH inhibition by manganese (II) was neutralized significantly by elevated dose of iron. Consistent with this, the induction of cellular HIF-1alpha protein by manganese (II) was abolished by pretreatment with iron. Manganese (II) induced the HIF-1 target gene involved in pulmonary inflammation, vascular endothelial growth factor (VEGF), in lung carcinoma cell lines.The induction of VEGF was dependent on HIF-1. Manganese-induced VEGF promoted tube formation of HUVEC. Taken together, these data suggest that HIF-1 may be a potential mediator of manganese-induced pulmonary inflammation.

Extracts of oyster mushroom (Pleurotus ostreatus) grown on wheat ameliorate hepatotoxicity induced by carbon tetrachloride in rats

Pleurotus ostreatus (PO), which is also called the oyster mushroom, is the secondly most popular cultivated mushroom in the world and has been shown to display antioxidant activity. In this study, the hepatic protective effects of extracts of PO cultured in wheat (POW) on carbon tetrachloride (CCl4)-induced liver injury in rats were evaluated by analyzing blood markers of liver injury. Sprague-Dawley rats were pretreated with POW extracts (0, 0.5, and 1.0 g/kg) orally for 14 days prior to the administration of CCl4 for 3 days. Marked evaluation of alanine and aspartate aminotransferases, lactate dehydrogenase, alkaline phosphatase, and γ-glutamyltransferase were observed in the plasma from control rats after CCl4 treatment. This increased liver injury markers were significantly reduced in a dose-dependent manner by pretreatment with the POW extract, suggesting that POW prevented acute liver damage in CCl4-intoxicated rats by suppressing cellular leakage and loss of the functional integrity of cell membranes in the liver. POW extracts could also improve lipid profiles damaged caused by CCl4 in liver through a reducing plasma triglyceride and total cholesterol and a recovering plasma HDL-cholesterol. These results suggest that the extracts of POW ameliorate hepatotoxicity induced by CCl4 in the rat model.