Ok-Sun Bang

1H-NMR-based metabolomics study of cerebral infarction.

Background and Purpose— Stroke is one of the leading causes of adult disability and death in developing countries. However, early diagnosis is difficult and no reliable biomarker is currently available. Thus, we applied a 1H-NMR metabolomics approach to investigate the altered metabolic pattern in plasma and urine from patients with cerebral infarctions and sought to identify metabolic biomarkers associated with stroke. Methods— Metabolic profiles of plasma and urine from patients with cerebral infarctions, especially small vessel occlusion, were investigated using 1H-NMR spectroscopy coupled with multivariate statistical analysis, such as principal components analysis and orthogonal partial least-squares discriminant analysis. Results— Multivariate statistical analysis showed a significant separation between patients and healthy individuals. The plasma of stroke patients was characterized by the increased excretion of lactate, pyruvate, glycolate, and formate, and by the decreased excretion of glutamine and methanol; the urine of stroke patients was characterized by decreased levels of citrate, hippurate, and glycine. These metabolites detected from plasma and urine of patients with cerebral infarctions were associated with anaerobic glycolysis, folic acid deficiency, and hyperhomocysteinemia. Furthermore, the presence of cerebral infarction in the external validation model was predicted with high accuracy. Conclusions— These data demonstrate that a metabolomics approach may be useful for the effective diagnosis of cerebral infarction and for the further understanding of stroke pathogenesis.

Akt as a Mediator of Secretory Phospholipase A2 Receptor-Involved Inducible Nitric Oxide Synthase Expression

The induction of inducible NO synthase (iNOS) by group IIA phospholipase A2 (PLA2) involves the stimulation of a novel signaling cascade. In this study, we demonstrate that group IIA PLA2 up-regulates the expression of iNOS through a novel pathway that includes M-type secretory PLA2 receptor (sPLA2R), phosphatidylinositol 3-kinase (PI3K), and Akt. Group IIA PLA2 stimulated iNOS expression and promoted nitrite production in a dose- and time-dependent manner in Raw264.7 cells. Upon treating with group IIA PLA2, Akt is phosphorylated in a PI3K-dependent manner. Pretreatment with LY294002, a PI3K inhibitor, strongly suppressed group IIA PLA2-induced iNOS expression and PI3K/Akt activation. The promoter activity of iNOS was stimulated by group IIA PLA2, and this was suppressed by LY294002. Transfection with Akt cDNA resulted in Akt protein overexpression in Raw264.7 cells and effectively enhanced the group IIA PLA2-induced reporter activity of the iNOS promoter. M-type sPLA2R was highly expressed in Raw264.7 cells. Overexpression of M-type sPLA2R enhanced group IIA PLA2-induced promoter activity and iNOS protein expression, and these effects were abolished by LY294002. However, site-directed mutation in residue responsible for PLA2 catalytic activity markedly reduced their ability to production of nitrites and expression of iNOS. These results suggest that group IIA PLA2 induces nitrite production by involving of M-type sPLA2R, which then mediates signal transduction events that lead to PI3K/Akt activation.

Ethanol extract of Gleditsia sinensis thorn suppresses angiogenesis in vitro and in vivo

BackgroundGleditsia sinensis thorns have been widely used in traditional Korean medicine for the treatment of several diseases, including obesity, thrombosis, and tumor-related diseases. The aim of the study is to determine the antiangiogenic effect of Gleditsia sinensis thorns in vitro and in vivo in a bid to evaluate its potential as an anticancer drug.MethodsEthanol extract of Gleditsia sinensis thorns (EEGS) were prepared and used for in vitro and in vivo assays. In vitro antiangiogenic effect of EEGS was determined in HUVEC primary cells by cell migration and tube formation assays. In vivo antiangiogenic effect of EEGS was determined by measuring vessel formation and vascular endothelial cells migrating into the implanted matrigels in nude mice. The angiogenesis-related proteins of which expression levels were altered by EEGS were identified by proteomic analysis.ResultsEEGS exerted a dose-dependent antiproliferative effect on HUVEC cells without significant cytotoxicity. Angiogenic properties, such as cell migration and tube formation, were significantly inhibited by EEGS in a dose-dependent manner. New vessel formation was also suppressed by EEGS, as determined by the directed in vivo angiogenesis assays in nude mice. EEGS reduced the expression of proangiogenic proteins, endothelin 1 and matrix metallopeptidase 2, in HUVEC cells.ConclusionsOur findings suggest that EEGS can inhibit angiogenesis by down-regulating proangiogenic proteins, and therefore it should be considered as a potential anticancer drug targeting tumor-derived angiogenesis.

Gene Expression Profile of the A549 Human Non-Small Cell Lung Carcinoma Cell Line following Treatment with the Seeds of Descurainia sophia, a Potential Anticancer Drug

Descurainia sophia has been traditionally used in Korean medicine for treatment of diverse diseases and their symptoms, such as cough, asthma, and edema. Our previous results showed that ethanol extract of the seeds of D. sophia (EEDS) has a potent cytotoxic effect on human cancer cells. In this study, we reveal the molecular events that are induced by EEDS treatment in A549 human lung cancer cells. The dose-dependent effect of EEDS on gene expression was measured via a microarray analysis. Gene ontology and pathway analyses were performed to identify functional involvement of genes regulated by EEDS. From gene expression analyses, two major dose-dependent patterns were observed after EEDS treatment. One pattern consisted of 1,680 downregulated genes primarily involved in metabolic processes (FDR < 0.01). The second pattern consisted of 1,673 upregulated genes primarily involved in signaling processes (FDR < 0.01). Pathway activity analyses revealed that the metabolism-related pathways and signaling-related pathways were regulated by the EEDS in dose-dependent and reciprocal manners. In conclusion, the identified biphasic regulatory mechanism involving activation of signaling pathways may provide molecular evidence to explain the inhibitory effect of EEDS on A549 cell growth.

Cytotoxic Compounds from the Fruits of Vitex rotundifolia against Human Cancer Cell Lines

Activity-guided fractionation of an ethanol extract from the fruits of Vitex rotundifolia led to the isolation of three flavonoids (1–3), one lignan (4), and three phenolic compounds (5–7). The structures of compounds 1–7 were identified by NMR data. The efficacy of all compounds was evaluated by their cytotoxic activities against nine human cancer cell lines using an in vitro assay.

Magnolol Suppresses Vascular Endothelial Growth Factor-Induced Angiogenesis by Inhibiting Ras-Dependent Mitogen-Activated Protein Kinase and Phosphatidylinositol 3-Kinase/Akt Signaling Pathways

Magnolol, a hydroxylated biphenyl compound isolated from Magnolia officinalis, has been reported to possess anticancer activity. Recent studies have also demonstrated that magnolol inhibits cell growth and induces the apoptosis of cancer cells. However, the effects of magnolol on vascular endothelial growth factor (VEGF)-induced angiogenesis in endothelial cells have not been studied. In the present study, we have used human umbilical vein endothelial cells (HUVECs) to investigate the antiangiogenic effect and molecular mechanism of magnolol. Magnolol inhibited the VEGF-induced proliferation, chemotactic motility and tube formation of HUVECs in vitro as well as the vessel sprouting of the aorta ex vivo. Furthermore, magnolol inhibited VEGF-induced Ras activation and subsequently suppressed extracellular signal-regulated kinase (ERK), phosphatidylinositol-3-kinase (PI3K)/Akt and p38, but not Src and focal adhesion kinase (FAK). Interestingly, the knockdown of Ras by short interfering RNA produced inhibitory effects that were similar to the effects of magnolol on VEGF-induced angiogenic signaling events, such as ERK and Akt/eNOS activation, and resulted in the inhibition of proliferation, migration, and vessel sprouting in HUVECs. In combination, these results demonstrate that magnolol is an inhibitor of angiogenesis and suggest that this compound could be a potential candidate in the treatment of angiogenesis-related diseases.

Evaluation of anti-tumorigenic activity of BP3B against colon cancer with patient-derived tumor xenograft model

BackgroundKIOM-CRC#BP3B (BP3B) is a novel herbal prescription that is composed of three plant extracts. Our preliminary study identified that BP3B exhibited potent anti-proliferative activity against various types of cancer cell lines in vitro. Because the in vivo anti-tumor effect of BP3B is not evaluated before clinical trial, we want to test it using patient’s samples.MethodsTo confirm the in vivo anti-cancer effect of BP3B, we used genetically characterized patient-derived colon tumor xenograft (PDTX) mouse model. Anti-cancer activity was evaluated with apoptosis, proliferation, angiogenesis and histological analysis.ResultsOral administration of BP3B significantly inhibited the tumor growth in two PDTX models. Furthermore, TUNEL assay showed that BP3B induced apoptosis of tumor tissues, which was associated with degradation of PARP and Caspase 8 and activation of Caspase 3. We also observed that BP3B inhibited cancer cell proliferation by down-regulation of Cyclin D1 and induction of p27 proteins. Inhibition of angiogenesis in BP3B-treated group was observed with immunofluorescence staining using CD31 and Tie-2 antibodies.ConclusionThese findings indicated that BP3B has a strong growth-inhibitory activity against colon cancer in in vivo model and will be a good therapeutic candidate for treatment of refractory colon cancer.

Pyranocoumarins from Root Extracts of Peucedanum praeruptorum Dunn with Multidrug Resistance Reversal and Anti-Inflammatory Activities

In the search for novel herbal-based anticancer agents, we isolated a new angular-type pyranocoumarin, (+)-cis-(3′S,4′S)-3′-angeloyl-4′-tigloylkhellactone (1) along with 12 pyranocoumarins (2–13), two furanocoumarins (14, 15), and a polyacetylene (16) were isolated from the roots of Peucedanum praeruptorum using chromatographic separation methods. The structures of the compounds were determined using spectroscopic analysis with nuclear magnetic resonance (NMR) and high-resolution-electrospray ionization-mass spectrometry (HR-ESI-MS). The multidrug-resistance (MDR) reversal and anti-inflammatory effects of all the isolated compounds were evaluated in human sarcoma MES-SA/Dx5 and lipopolysaccharide (LPS)-induced RAW 264.7 cells. Among the 16 tested compounds, two (2 and 16) downregulated nitric oxide (NO) production and five (1, 7, 8, 11, and 13) inhibited the efflux of drugs by MDR protein, indicating the reversal of MDR. Therefore, these compounds may be potential candidates for the development of effective agents against MDR forms of cancer.

An evaluation of the anti-angiogenic effect of the Korean medicinal formula “Sa-mi-yeon-geon-tang” in vitro and in ovo

BackgroundAngiogenesis is a general hallmark of cancer; therefore, the inhibition of tumor-derived angiogenesis is considered to be an attractive target in the development of anti-cancer agents. Sa-mi-yeon-geon-tang (SMYGT), a decoction that consists of four natural medicinal products, has been traditionally prescribed in Oriental medicine to treat diverse diseases, including cancer. In the present study, we investigated the anti-angiogenic potential of SMYGT in vitro and in ovo.MethodsThe anti-angiogenic potential of SMYGT was evaluated using conventional in vitro assays with human umbilical vein endothelial cells (HUVECs) and chorioallantoic membrane (CAM) assays with fertilized eggs. The expression changes of pro-angiogenic proteins and intracellular signaling in HUVECs following SMYGT treatment were determined by quantitative polymerase chain reaction, gelatinase zymography, and western blot analysis.ResultsSMYGT efficiently inhibited three-dimensional capillary-like tube formation by HUVECs on extracellular matrix supports, as well as new vessel formation on CAMs. SMYGT inhibited cell adhesion to the extracellular matrix and HUVEC cell invasion through Matrigel without affecting cell proliferation, viability, and motility. These anti-angiogenic effects of SMYGT in HUVECs were related to decreases in the phosphorylation of focal adhesion kinase and the expression of matrix metallopeptidase-2 activity.ConclusionsSMYGT exhibited an anti-angiogenic potential in both in vitro and in ovo experiments, which may partially contribute to its anti-tumor effect in clinical conditions. We suggest that SMYGT may be a promising source material for the development of anti-cancer chemotherapeutics that target angiogenesis.

Anti-angiogenic potential of an ethanol extract of Annona atemoya seeds in vitro and in vivo

BackgroundAngiogenesis, which is initiated by certain tumor micro-environmental conditions and diverse protein factors, plays a pivotal role during tumor development and metastasis. Therefore, many efforts have been made to develop effective anti-angiogenic agents as anticancer therapeutics. In the current study, we investigated the anti-angiogenic potential of an ethanol extract of Annona atemoya seeds (EEAA) in vitro and in vivo.MethodsThe anti-angiogenic potential of EEAA was evaluated using various in vitro/in vivo models, including cell proliferation, migration, and tube formation by human umbilical vascular endothelial cells (HUVECs); a Matrigel plug assay; and tumor-induced angiogenesis. The expression of hypoxia-inducible factors (HIFs) and vascular endothelial growth factor (VEGF) was investigated using reverse transcription-polymerase chain reaction, immunoassays, and western blotting.ResultsEEAA was able to significantly inhibit the angiogenic properties of HUVECs in vitro as well as angiogenic factor-induced blood vessel formation in vivo. EEAA down-regulated the expression of VEGF and HIF-1alpha/2alpha at the mRNA and protein levels, respectively, in cancer cells under hypoxic conditions.ConclusionsEEAA shows a strong anti-angiogenic potential in both in vitro and in vivo systems, and we suggest that EEAA may be a valuable herbal source for anticancer drug development.