Quercetin 3,5,7,3',4'-pentamethyl ether from Kaempferia parviflora directly and effectively activates human SIRT1.

Sirtuin 1 (SIRT1), an NAD+-dependent deacetylase, is a crucial regulator that produces multiple physiological benefits, such as the prevention of cancer and age-related diseases. SIRT1 is activated by sirtuin-activating compounds (STACs). Here, we report that quercetin 3,5,7,3',4'-pentamethyl ether (KPMF-8), a natural STAC from Thai black ginger Kaempferia parviflora, interacts with SIRT1 directly and stimulates SIRT1 activity by enhancing the binding affinity of SIRT1 with Ac-p53 peptide, a native substrate peptide without a fluorogenic moiety. The binding affinity between SIRT1 and Ac-p53 peptide was enhanced 8.2-fold by KPMF-8 but only 1.4-fold by resveratrol. The specific binding sites of KPMF-8 to SIRT1 were mainly localized to the helix2-turn-helix3 motif in the N-terminal domain of SIRT1. Intracellular deacetylase activity in MCF-7 cells was promoted 1.7-fold by KPMF-8 supplemented in the cell medium but only 1.2-fold by resveratrol. This work reveals that KPMF-8 activates SIRT1 more effectively than resveratrol does.

A simple and effective preparation of quercetin pentamethyl ether from quercetin.

Among the five hydroxy (OH) groups of quercetin (3,5,7,3',4'-pentahydroxyflavone), the OH group at 5 position is the most resistant to methylation due to its strong intramolecular hydrogen bonding with the carbonyl group at 4 position. Thus, it is generally difficult to synthesize the pentamethyl ether efficiently by conventional methylation. Here, we describe a simple and effective per-O-methylation of quercetin with dimethyl sulfate in potassium (or sodium) hydroxide/dimethyl sulfoxide at room temperature for about 2 hours, affording quercetin pentamethyl ether (QPE) quantitatively as a single product. When methyl iodide was used in place of dimethyl sulfate, the C-methylation product 6-methylquercetin pentamethyl ether was also formed. A computational study provided a rationale for the experimental results.

Changes in intracellular copper concentration and copper-regulating gene expression after PC12 differentiation into neurons.

It is suspected that some neurodegenerative diseases are a result of the disturbance of copper (Cu) homeostasis, although it remains unclear whether the disturbance of Cu homeostasis has aberrant effects on neurons. Herein, we investigated Cu metabolism specifically in neurons in terms of changes in the intracellular Cu concentration and the expression of Cu-regulating genes, such as Cu transporters and metallothioneins (MTs), before and after the differentiation of rat pheochromocytoma cells (PC12 cells) into neurons. After the differentiation, Cu and Zn imaging with fluorescent probes revealed an increase in intracellular Cu concentration. The concentrations of other essential metals, which were determined by an inductively coupled plasma mass spectrometer, were not altered. The mRNA expression of the Cu influx transporter, Ctr1, was decreased after the differentiation, and the differentiated cells acquired tolerance to Cu and cisplatin, another substrate of Ctr1. In addition, the expression of MT-3, a brain-specific isoform, was increased, contrary to the decreased expression of MT-1 and MT-2. Taken together, the differentiation of PC12 cells into neurons induced MT-3 expression, thereby resulting in intracellular Cu accumulation. The decrease in Ctr1 expression was assumed to be a response aimed at abolishing the physiological accumulation of Cu after the differentiation.

Phase II trial of panitumumab with irinotecan as salvage therapy for patients with advanced or recurrent colorectal cancer (TOPIC study).

Little is known about the clinical impact of salvage panitumumab with irinotecan for metastatic colorectal cancer (mCRC) patients. The present study conducted a single-arm, multicenter phase II trial for mCRC with skin toxicity prevention program. The subjects were mCRC patients with wild-type KRAS, who showed resistance to fluoropyrimidine, oxaliplatin and irinotecan. Panitumumab was administered at a dose of 6 mg/kg every 2 weeks by intravenous infusion over 60 min, and irinotecan was administered at a dose of 100-180 mg/m2 every 2 weeks by intravenous infusion over 90 min, depending on the preceding treatment dose. To prevent skin toxicities, a moisturizer was applied and oral antibiotics (100 mg minocycline twice daily) were initiated for 6 weeks. The primary endpoint was the response rate (RR) determined by independent reviewers. Secondary endpoints were the disease control rate (DCR), progression-free survival (PFS) time, overall survival (OS) time and adverse events. A total of 35 patients were enrolled between October 2010 and March 2012. The median age was 61 years (range, 41-76 years), with 25 male and 10 female patients. The initial irinotecan dose was 150 mg/m2 in 19 patients and 180 mg/m2 in 1 patient. The remaining patients were treated with ≤120 mg/m2. A central review indicated a partial response in 8 patients (22.9%) and stable disease in 6 patients (17.1%), with an RR of 22.9% (95% confidence interval, 12.1-39.0) and a DCR of 40%. The RR of the patients with standard-dose irinotecan (150 or 180 mg/m2) was 30%, although that of low-dose irinotecan (100-120 mg/m2) was 13%. The median PFS time was 2.7 months, and the median OS time was 6.3 months. A grade 3 or above acne-like rash developed in 25.7% of patients. In conclusion, panitumumab and irinotecan as salvage therapy for mCRC KRAS wild-type patients with skin toxicity prevention exhibits limited efficacy. In particular, the effect of low-dose irinotecan with panitumumab appears to be clinically insignificant. Routine use of skin toxicity prevention is currently under evaluation.

A rare complication: misdirection of an indwelling urethral catheter into the ureter.

We report 3 patients with the rare complication of an indwelling urethral catheter misdirected into the ureter. This is the largest series to date. Patients were referred to us for a variety of reasons following exchange of their chronic indwelling urinary catheters. CT in all cases demonstrated the urinary catheters residing in the left ureter. The ages of the patients were 37, 67 and 81 years old. All patients suffered from neurogenic bladder. Two patients were female, one was male, and 2 of the 3 had a sensory disorder inhibiting their pain response. The catheters were replaced with open-end Foley catheters. Extensive follow-up CT scans were obtained in one case, demonstrating improvement of hydronephrosis and no evidence of ureteral stenosis. Cystoscopy in this patient demonstrated normally positioned and functioning ureteral orifices. Although the placement of an indwelling urethral catheter is a comparatively safe procedure, one must keep in mind that this complication can occur, particularly in female patients with neurogenic bladder. CT without contrast is a noninvasive, definitive diagnostic tool.

Mechanism of nanoparticle formation from ternary coground phenytoin and its derivatives.

The mechanism of drug nanoparticle formation of phenytoin (DPH) and its derivatives monomethylphenytoin (MDPH) and dimethylphenytoin (DMDPH) was investigated. The drug, polyvinylpyrrolidone K17 (PVP), and sodium dodecyl sulfate were coground to obtain the ground mixture (GM). The DPH GM was amorphous; however, MDPH and DMDPH GMs contained drug crystals. Spectral changes in infrared and (13)C solid-state nuclear magnetic resonance were observed in the DPH GM, partially observed in the MDPH GM, and hardly observed in the DMDPH GM. Mean particle sizes of the DPH, MDPH, and DMDPH GM nanosuspension were almost the same; however, stability after storage differed in the order of DPH > MDPH > DMDPH. The intermolecular interaction between the drug and PVP reflected not only the crystallinity of the drug in the GM but also the stability of the GM suspension. The size and stiffness of drug nanoparticles were evaluated using atomic force microscopy. Crystallization of the amorphous GM and agglomeration of the primary nanocrystals were observed in the DPH GM suspension. In contrast, primary nanocrystals were observed in the DMDPH GM suspension. The size of the drug nanocrystals formed from the different molecular states of the drug in the GM reflects the agglomerated states in water and stability.

New 2-aryl-1,4-naphthoquinone-1-oxime methyl ether compound induces microtubule depolymerization and subsequent apoptosis.

In this study, we describe the antitumor activity of QO-1, one of the new 2-aryl-1,4-naphthoquinone-1-oxime methyl ether derivatives. QO-1 is a derivative of macarpine, a natural occurring product from Rutaceae plant. It could potently inhibit cell growth when tested on 19 cancer cell lines. To investigate its mechanism, two cell lines (HeLa and MCF-7) sensitive to QO-1 were selected. Based on flow cytometry, it was found to induce G(2)/M-phase arrest. Moreover, it could cause microtubule depolymerization both in vitro and in vivo. On the other hand, QO-1 activated spindle assembly checkpoint (SAC) proteins. Expression of Bub1, one of the SAC, was gradually increased, reaching a peak after 16 - 20 h, and then gradually decreased. Instead, QO-1 increased the sub-G(1) population, which suggested a cell death population. Actually, expression of Bcl-2 family proteins and activation of caspase-3/7 were evidences of apoptosis. Consistent with these results, cells with DNA fragmentation and multinucleated cells were increased time-dependently after QO-1 exposure. In conclusion, QO-1 has promising antitumor effects via microtubule depolymerization.

Effects of restricted feeding on fetal and placental development in pregnant rabbits.

In our previous study on the effects of restricted feeding on pregnant rabbits (Matsuoka et al., 2009), animals given 20 g/day of diet on and after gestation day 6 (GD 6) showed significant changes in blood coagulation-related parameters suggesting a tendency to bleed and a decrease in serum concentration of progesterone, an important factor to maintain pregnancy, on GD 22, and a half of them showed serum progesterone concentrations less than 4.0 ng/ml which resulted in abortions on and after GD 23. In the present study, the effects of restricted feeding of 20 g/day from GD 6 to GD 22 on embryo-fetal and placental development on GD 23 as well as on blood coagulation-related parameters and serum progesterone concentrations on GD 22 were examined in pregnant rabbits. As compared with the non-restricted feeding (Not-treated, NT) group, the restricted feeding (RF) group showed lower values of platelets, fibrinogen, activated partial thromboplastin time (APTT) and antithrombin III (ATIII) and a longer prothrombin time (PT), reflecting an inhibition of blood coagulation, and a decrease in serum progesterone concentration on GD 22. Cesarean section performed on GD 23 revealed that the RF group showed a tendency towards an increase in the embryo-fetal death index and lower body weights and placental volumes compared with the NT group. Histological examination of the placenta in the RF group revealed that the labyrinth zone was thin and many glycogen-containing cells still remained in the basal zone, suggesting a delay in placental growth.

Angiogenesis inhibitors identified by cell-based high-throughput screening: synthesis, structure-activity relationships and biological evaluation of 3-[(E)-styryl]benzamides that specifically inhibit endothelial cell proliferation.

Proliferation of endothelial cells is critical for angiogenesis. We report orally available, in vivo active antiangiogenic agents which specifically inhibit endothelial cell proliferation. After identifying human umbilical vein endothelial cell (HUVEC) proliferation inhibitors from a cell-based high-throughput screening (HTS), we eliminated those compounds which showed cytotoxicity against HCT116 and vascular endothelial growth factor receptor 2 (VEGFR-2) inhibitory activity. Evaluations in human Calu-6 xenograft model delivered lead compound 1. Following extensive lead optimization and alteration of the scaffold we discovered 32f and 32g, which both inhibited the proliferation and tube formation of HUVEC without showing inhibitory activity against any of 25 kinases or cytotoxicity against either normal fibroblasts or 40 cancer cell lines. Upon oral administration, 32f and 32g had good pharmacokinetic profiles and potent antitumor activity and decreased microvessel density (MVD) in Calu-6 xenograft model. Combination therapy with a VEGFR inhibitor enhanced the in vivo efficacy. These results suggest that 32f and 32g may have potential for use in cancer treatment.

Matched case-control study comparing endoscopic submucosal dissection and endoscopic mucosal resection for colorectal tumors.

BACKGROUND AND AIM: For large colorectal tumors, the en bloc resection rate achieved by endoscopic mucosal resection (EMR) is insufficient, and this leads to a high rate of local recurrence. As endoscopic submucosal dissection (ESD) has been reported to achieve a higher rate of en bloc resection and a lower rate of local recurrence in the short-term, it is expected to overcome the limitations of EMR. We conducted a matched case-control study between ESD and EMR to clarify the effectiveness of ESD for colorectal tumors. METHODS: Between April 2005 and February 2009, a total of 28 colorectal tumors in 28 patients were resected by ESD and were followed up by colonoscopy at least once. As a control group, 56 EMR cases from our prospectively completed database were matched. En bloc resection, complication and recurrence rates were compared between the two groups. RESULTS: The mean sizes of the lesions were 27.1 mm in the ESD group and 25.0 mm in the EMR group. The en bloc resection rate was significantly higher in the ESD group (92.9% vs 37.5% with ESD vs EMR), and the rate of perforation was also significantly higher (10.7% vs 0%). All cases of perforation were managed conservatively. No recurrence was observed in the ESD group, whereas local recurrences were detected in 12 EMR cases (21.4%). Eleven of the 12 recurrences (91.7%) were managed endoscopically, and one required surgical resection. CONCLUSIONS: Endoscopic submucosal dissection is a promising technique for the treatment of colorectal tumors, giving an excellent outcome in comparison with EMR.

Biologically active constituents of Aglaia erythrosperma.

From the fruits and leaves of Aglaia erythrosperma (Meliaceae), 10 chemical constituents were isolated and identified, i.e. the dammarane triterpenoids cabraleadiol (1), cabraleahydroxylactone (2), ethyl eichlerianoate (3), eichlerialactone (4), aglinin A (5), cabralealactone (6), the aglaialactone 5,6-desmethylenedioxy-5-methoxy-aglalactone (7), the flavagline 4'-demethoxy-3',4'-methylenedioxy-methyl rocaglate (8) and two coumarins: scoparone and scopoletin. Flavagline 8 exhibited antimalarial activity with an IC(50) value of 7.30 µg mL(-1) and was strongly cytotoxic against small cell lung cancer (NCI-H187), epidermoid carcinoma (KB) and breast cancer (BC) cell lines, with IC(50) values of 2.17, 2.10 and 0.11 µg mL(-1), respectively. Aglinin A (5) displayed moderate cytotoxicity against all the three cancer cell lines, whereas ethyl eichlerianoate (3), cabralealactone (6) and the aglaialactone 7 were exclusively cytotoxic to NCI-H187 cell line. Cabraleahydroxylactone (2) showed antiviral activity against herpes simplex virus type-1 with an IC(50) value of 3.20 µg mL(-1), in comparison with the standard acyclovir (IC(50) = 1.90 µg mL(-1)). When tested for antimycobacterial activity against Mycobacterium tuberculosis H(37)Ra, compounds 1-4 and 6-8 displayed minimum inhibitory concentration in the range of 25-50 µg mL(-1).

2-Aryl-1,4-naphthoquinone-1-oxime methyl ethers: their cytotoxic activity.

Preliminary examination for the structure-activity relationship of quinone monooxime derivatives on cytotoxicity against HeLa S3 cell and further trials using eight different cell lines suggested that 2-aryl-6,7-methylenedioxy-1,4-naphthoquinone-1-oxime methyl ethers, carrying 2-methoxy-4,5-methylenedioxyphenyl, 7-methoxy-2-methylbenzofuran-4-yl, and 2-methoxycarbonyl-3,4-dimethoxyphenyl as the 2-aryl substituent, were potential candidates for anti-cancer drugs.

Diagnosis of breast cancer with multidetector computed tomography: analysis of optimal delay time after contrast media injection.

PURPOSE: The aim of this study was to investigate the optimal delay time after a contrast media injection for multidetector computed tomography (MD-CT) images in the diagnosis of breast cancer patients. MATERIALS AND METHODS: Thirty-one patients who underwent MD-CT for their preoperative examination and who had postoperatively confirmed pathology were enrolled. Four-phase images of dynamic contrast enhanced study were acquired using four-detector MDCT. All cases were mammographically classified into two groups according to BI-RADS: nondense and dense groups. The CT value of the background mammary gland, background breast enhancement (BBE), and tumor-background mammary gland contrast (TBC) were compared between the two groups. RESULTS: The CT value of the dense group was significantly higher than that of the nondense group in all phases. BBE in both nondense and dense groups showed no significant differences in any of the phases. In the nondense group, TBC was significantly higher in both the second and the third phases than in the first phase, while in the dense group, TBC was significantly higher in the second phase than in the first and third phases. CONCLUSION: The optimal delay time to depict breast cancer is 80 s after a contrast media injection, regardless of the density level of the background mammary gland.

Effects of restricted feeding on blood parameters in pregnant rabbits.

The effects of restricted feeding (20 g/day from gestational day (GD) 6 to 28) on pregnancy outcome and blood parameters were examined in pregnant rabbits. As compared with the group which was allowed free access to diet throughout the gestational period (NT group), the group subjected to restricted feeding (R group) showed significantly lower values in many parameters such as total protein, albumin and triglyceride on GDs 22 and 28, reflecting low nutritive conditions. In addition, there were significant changes in blood coagulation-related parameters, suggesting an imbalance between coagulation and anti-coagulation factors. Moreover, abortions occurred in about half of the animals of the R group between GDs 23 and 27. When aborted rabbits were compared with those which could maintain pregnancy under restricted feeding, total protein, albumin, platelets and antithrombin III values and especially blood progesterone concentration were significantly lower in aborted rabbits on GD 22, prior to occurrence of abortion. These results suggested that abortions due to restricted feeding might be brought about by lower nutritive conditions, an imbalance of blood coagulation-related factors and lower blood progesterone concentrations.

The structure-activity relationship between oxycoumarin derivatives showing inhibitory effects on iNOS in mouse macrophage RAW264.7 cells.

We have investigated the structure-activity relationship between 63 natural oxycoumarin derivatives and their effects on the expression of inducible-nitric oxide synthase (iNOS) induced by lipopolysaccharide. The protein expression of iNOS was screened by Western blot analysis, and four 5,7-dimethoxycoumarins were selected as potent inhibitors of iNOS expression. In terms of structural specificity, the methoxyl group on C-5 and C-7 and the short alkyl chain (1-5 carbons) on C-6 may be essential for the potent activities. These compounds also showed inhibitory effects on nitric oxide generation and mRNA expression of inflammatory mediators, namely, iNOS and COX-2. Interestingly, the inhibitory effect on mRNA expression was specific for iNOS and was not detected for neuronal NOS. It is expected that these compounds will show anti-inflammatory activities via inhibition of the expressions of iNOS and COX-2.

Inhibitory effect of the extracts from Thai medicinal plants on iNOS expression in mouse macrophage RAW 264.7.

In the present study, we screened the inhibitory effect of the extract from 50 Thai medicinal plants on an inducible-nitric oxide synthase (iNOS) expression induced by lipopolysaccharide (LPS) in mouse macrophages RAW 264.7. From this screening, the extracts of root bark of Clausena guillauminii, C. lunulata, and C. excavata (Rutaceae) were found as the extracts which showed potent inhibitory effect on the iNOS protein expression in concentration-dependent manner. Furthermore, hydrophobic active components may exist in C. guillauminii.

Inhibitory effect of oxycoumarins isolated from the Thai medicinal plant Clausena guillauminii on the inflammation mediators, iNOS, TNF-alpha, and COX-2 expression in mouse macrophage RAW 264.7.

In the present study, we investigated the inhibitory effect of the known oxycoumarins poncitrin (3), osthol (4), and xanthoxyletin (5), newly isolated from Clausena guillauminii (Rutaceae), together with the known carbazoles heptaphylline (1) and 7-methoxyheptaphylline (2) on inducible-nitric oxide synthase (iNOS) expression induced by lipopolysaccharide (LPS) and the NO generation in RAW 264.7 mouse macrophages. Isolation of active oxycoumarins was guided by Western blot analysis of iNOS protein expression. These oxycoumarins showed an inhibitory effect on iNOS protein expression at 10 microM. Further examination of the inhibitory effects of these compounds on inflammation mediators revealed that the synthesis of nitric oxide (NO) and the protein expression of tumor necrosis factor-alpha (TNF-alpha) and cyclooxygenase-2 (COX-2) were inhibited by 5. It was expected that these compounds show anti-inflammatory activities.

Insight into estrogenicity of phytoestrogens using in silico simulation.

Phytoestrogens, including miroestrol and deoxymiroestrol, have the ability to act through competition with estrogen for binding to the estrogen receptor (ER). Here, we utilize manual ligand docking followed by molecular dynamics simulations and binding free energy calculations with the linear interaction energy method to predict the binding modes and the binding affinities of phytoestrogens on the ligand binding domain of ER (ERalpha-LBD). The calculations brought about the good correlation between the calculated binding free energy and the bioassays. Furthermore, consideration of Lennard-Jones and Coulomb interaction energies of miroestrol and deoxymiroestrol on ERalpha-LBD provided the information to develop the phytoestrogen derivatives as the preferred drug for ER positive breast cancer treatment.

Pueraria mirifica phytoestrogens improve dyslipidemia in postmenopausal women probably by activating estrogen receptor subtypes.

Impaired lipid metabolism is an important health problem in postmenopausal women with insufficient estrogens, because dyslipidemia is a risk factor for development of atherosclerosis and the incidence of cardiovascular disease markedly increases after menopause. Pueraria mirifica (PM), a Thai herb, has been noticed as a source of phytoestrogens, estrogen-mimicking plant compounds. However, the clinical effects of PM on lipid metabolism and the underlying molecular mechanisms remain undetermined. Therefore, we examined the effects of PM on serum lipid parameters in a randomized, double-blind, placebo-controlled clinical trial. Nineteen postmenopausal women were randomly assigned to receive oral administration of PM powder or placebo. After 2 months of treatment, the PM group showed a significant increase in serum concentrations of high-density lipoprotein (HDL) cholesterol and apolipoprotein (apo) A-1 (34% and 40%, respectively), and a significant decrease in low-density lipoprotein (LDL) cholesterol and apo B (17% and 9%, respectively), compared with baseline measurements. Moreover, significant decreases were observed in the ratios of LDL cholesterol to HDL cholesterol (37%) and apo B to apo A-1 (35%). Next, we determined the effects of PM phytoestrogens on the activation of estrogen receptor (ER)-mediated transactivation by transient expression assays of a reporter gene in cultured cells. Among PM phytoestrogens, miroestrol and coumestrol enhanced both ERalpha- and ERbeta-mediated transactivation, whereas other phytoestrogens, including daidzein and genistein, preferentially enhanced ERbeta-mediated transactivation. In conclusion, PM has a beneficial effect on lipid metabolism in postmenopausal women, which may result from the activation of gene transcription through selective binding of phytoestrogens to ERalpha and ERbeta.