Search

Geranylated coumarins named mammeasins G-J (1-4) were isolated from the methanol extract of the flowers of Mammea siamensis (Miq.) T. Anders. (Calophyllaceae) originating in Thailand. Their structures were established based on detailed spectroscopic analyses. The isolates, including previously reported coumarin constituents (5-28), exhibited anti-proliferative activities against human carcinoma cell lines HSC-2, HSC-4, MKN-45, and MCF-7. Mammeasin A (7, IC 50  = 13.6 μM) and surangin B (15, 15.2 μM), both consisting of the geranyl group, were found to show relatively strong activities against HSC-4 cells and their mechanisms of action were found to involve apoptotic cell death., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The Ca 2+ -activated Cl - channel ANO1 contributes to tumorigenesis and metastasis in several carcinomas including breast cancer (BCA). Cl - channels have recently been attracting attention as 'transcriptional modulators'. Human epidermal growth factor receptor 2 (HER2) is overexpressed in approximately 30% of patients with BCA, and anti-HER2 monoclonal antibodies such as trastuzumab have emerged as a treatment for metastatic BCA. Among the seven human BCA cell lines examined in the present study, MDA-MB-453 and YMB-1 cells were HER2-positive; however, YMB-1 cell viability showed resistance to trastuzumab. Whole-cell patch-clamp configurations indicated that ANO1 was the main Cl - conductance in YMB-1 cells, and the pharmacological and siRNA-mediated inhibition of ANO1 significantly prevented HER2 transcription in YMB-1 cells. The expression levels of insulin-like growth factor-binding protein 5 (IGFBP5), which is a risk factor for BCA recurrence and metastasis, was not affected by the inhibition of ANO1 in YMB-1 cells. These results suggest that ANO1 Cl - channels may function as a transcriptional regulator of HER2, and ANO1 inhibitors have potential in the treatment of BCA patients with resistance to HER2-targeted therapy., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: The usefulness of ultrasound-guided needle aspiration for subpleural lesions has been reported. However, no reports have evaluated its usefulness and safety in patients with respiratory comorbidities such as chronic obstructive pulmonary disease (COPD) and interstitial pneumonia (IP), which can increase the risk of iatrogenic pneumothorax. In this study, we evaluated the influence of chronic respiratory diseases (CRDs) on the usefulness and safety of ultrasound-guided needle aspiration for subpleural lesions., Methods: Between January 2000 and September 2011, we examined 144 patients with intrapulmonary subpleural lesions. We retrospectively reviewed clinical data, including lesion size on thoracic computed tomography (CT), ultrasound findings, pathological findings obtained by ultrasound-guided needle aspiration, final diagnosis, and complications., Results: A positive definitive diagnosis was obtained in 74.3% of all 144 patients; 84.7% patients with malignant diseases, including lung cancer; and 26.9% patients with benign diseases. Of the 144 patients, 64 belonged to the CRD group and 80 to the non-CRD group. The former included 31 patients with COPD, six with emphysematous changes on thoracic CT, 17 with IP, and 10 with other diseases. The positive rate of diagnosis for malignant diseases was 84.7% in the CRD group, which was the same as that in the non-CRD group. With regard to complications related to ultrasound-guided aspiration, there were only two cases of pneumothorax in the CRD group and one in the non-CRD group., Conclusion: Ultrasound-guided aspiration is safe and useful for subpleural lesions, particularly malignant lesions, even in patients with respiratory comorbidities such as COPD and IP., (Copyright © 2015 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.)

Solitary fibrous tumor (SFT) of the pleura is a rare tumor of mesenchymal origin. Although radiographic findings of thoracic computed tomography and magnetic resonance imaging in the evaluation of SFTs of the pleura have been documented, the value of ultrasonography is uncertain. We presented the ultrasonographic findings of 3 pathologically proven cases of SFTs arising from the visceral pleura. In all the cases, thoracic ultrasonography demonstrated homogeneous, hypoechoic, hemicycle, extrapulmonary lesions, which showed respiratory movement with the adjacent lung, consistent with pedunculated tumors. Preoperative thoracic ultrasonography could be useful in the evaluation of patients with pleural tumors, especially SFTs., (© 2013 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.)

Aims: The vanilloid type 4 transient receptor potential channel (TRPV4) is a potential environmental sensor to multiple stimuli in many types of cells. In this study, we show that TRPV4 activated by 4α-phorbol 12,13-didecanoate (4αPDD) and hypo-osmotic stimulation (HOS) is a regulator of intracellular calcium ([Ca(2+)](i)) in human brain capillary endothelial cells (HBCEs), and its activation can partially regulate cell proliferation of HBCEs., Main Methods: The expression of TRPV4 in HBCEs was analyzed at the mRNA and protein levels. The function of TRPV4 in HBCEs was evaluated using a TRPV4 agonist, 4αPDD, and HOS while measuring [Ca(2+)](i) and membrane currents., Key Findings: Analysis of the mRNA transcripts of the TRPV subfamily revealed that TRPV2 and TRPV4 were expressed in HBCEs. Immunoreactivity to the TRPV4 protein was also detected in HBCEs, which were positively stained by von Willebrand factor and CD31. When 4αPDD was applied, [Ca(2+)](i) in HBCEs was elevated in a concentration-dependent manner. In addition, exposure of HBCEs to HOS at 228mOsm induced an elevation of [Ca(2+)](i). Application of 4αPDD also activated non-selective cation currents (NSCCs). Pretreatment of HBCEs with short interference RNA targeting TRPV4 (siRNA) significantly reduced the 4αPDD-induced elevation of [Ca(2+)](i). When HBCEs were treated for 24h with concentrations of 4αPDD between 0.3 and 3 μM, the cell proliferation was potentiated in a concentration-dependent manner. The potentiation was partially inhibited in HBCEs treated with siRNA., Significance: These data suggest that endogenous TRPV4, which functions as a regulator of [Ca(2+)](i) in HBCEs, partially controls cell proliferation., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Treatment with DAPT, an inhibitor of the Notch-activating enzyme, γ-secretase is known to reduce damage to ischemic brain. However, the molecular mechanisms supporting this therapeutic effect are not fully understood. Here we demonstrated that Notch/RBP-J signaling is activated in NG2(+) glial progenitors and reactive astrocytes such as GFAP(+) cells, Nestin(+) cells and RC2(+) cells, using Notch/RBP-J signaling reporter mice. 3-day DAPT treatment reduced the number of reactive astrocytes but not NG2(+) glial progenitors. BrdU labeling experiments have shown that this reduction was due to decreased proliferation of reactive astrocytes. DAPT inhibited nuclear-translocation of Olig2, which is indispensable for proliferation and differentiation of reactive astrocytes. These findings suggest that Notch signaling might promote proliferation and differentiation of reactive astrocytes through the regulation of nucleo-cytoplasmic translocation of Olig2., (Copyright © 2013 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.)

Transient Receptor Potential Melastatin 3 (TRPM3) is a widely expressed calcium-permeable non-selective cation channel that is stimulated by high concentrations of nifedipine or by physiological steroids that include pregnenolone sulphate. Here we sought to identify steroids that inhibit TRPM3. Channel activity was studied using calcium-measurement and patch-clamp techniques. Progesterone (0.01-10μM) suppressed TRPM3 activity evoked by pregnenolone sulphate. Progesterone metabolites and 17β-oestradiol were also inhibitory but the effects were relatively small. Dihydrotestosterone was an inhibitor at concentrations higher than 1μM. Corticosteroids lacked effect. Overlay assays indicated that pregnenolone sulphate, progesterone and dihydrotestosterone bound to TRPM3. In contrast to dihydrotestosterone, progesterone inhibited nifedipine-evoked TRPM3 activity or activity in the absence of an exogenous activator, suggesting a pregnenolone sulphate-independent mechanism of action. Dihydrotestosterone, like a non-steroid look-alike compound, acted as a competitive antagonist at the pregnenolone sulphate binding site. Progesterone inhibited endogenous TRPM3 in vascular smooth muscle cells. Relevance of TRPM3 or the progesterone effect to ovarian cells, which have been suggested to express TRPM3, was not identified. The data further define a chemical framework for competition with pregnenolone sulphate at TRPM3 and expand knowledge of steroid interactions with TRPM3, suggesting direct steroid binding and pregnenolone sulphate-independent inhibition by progesterone., (Crown Copyright © 2011. Published by Elsevier India Pvt Ltd. All rights reserved.)

Aims: Vanilloid type transient receptor potential channel (TRPV) could be a potential environmental sensor to multiple stimuli in many types of cells. In this study, we provide the first evidence of functional vanilloid type 4 transient receptor potential channel (TRPV4) in rat cardiac fibroblasts (CFs)., Main Methods: Expression of TRPV4 in CFs was analyzed at mRNA and protein level. Function of TRPV4 in CFs was evaluated using a selective TRPV4 agonist, 4alpha-phorbol 12,13-didecanoate (4alphaPDD) while measuring intracellular Ca(2+) concentration ([Ca(2+)](i)) and membrane currents., Key Findings: Analysis of expression of mRNA transcripts of TRPV subfamily revealed that TRPV2 and TRPV4 were expressed in CFs. Significant immunoreactivity to TRPV4 protein was also detected in CFs. When 4alphaPDD was applied to CFs, [Ca(2+)](i) was elevated in a concentration-dependent manner. The elevation of [Ca(2+)](i) was abolished by the removal of external Ca(2+) and by ruthenium red (RuR). 4alphaPDD also activated non-selective cation currents (NSCCs), which were suppressed by RuR. Moreover, pretreatment of CFs with short interference RNA (siRNA) targeting TRPV4 significantly reduced both 4alphaPDD-induced elevation of [Ca(2+)](i) and NSCC., Significance: These results provide strong evidence that endogenous TRPV4 functions as an important regulator of [Ca(2+)](i) in CFs.

Neurogenesis persists in restricted regions of the adult vertebrate brain. However, the molecular mechanisms supporting adult neurogenesis are not fully understood. Here we demonstrated that C cell-specific deletion of RBP-J in the adult subventricular zones (SVZs) caused reduction in numbers of mature granule cells in the olfactory bulbs (OBs) with concomitant increase in Olig2(+) oligodendroglial progenitors, although generation of immature neurons was enhanced in the SVZs. Adenovirus-mediated Cre introduction to the SVZs of RBP-J-floxed mice indicated that Olig2(+) cells in the OBs can be generated from RBP-J-deficient SVZs, although no oligodendroglial cells in the OBs are derived from the normal SVZs. This preferential differentiation to oligodendroglial progenitor cells and reduction in differentiation of mature neurons were also confirmed by in vitro culture of RBP-J-deficient SVZ-derived neural progenitor cells, in addition to defects in the maintenance of adult neural stem cell population. The defects in maturation of RBP-J-deficient neurons could be partly rescued by knockdown of Olig2 in vivo. Our findings suggest that RBP-J might regulate neuronal maturation at least in part through transcriptional repression of Olig2.

Unlabelled: The purpose of this study is to evaluate the effect of C18 and C20 long chain fatty acids on tight junction permeability in a model of intestinal epithelium., Methods: Confluent Caco-2 cells on porous filters with double chamber system were used to measure fluorescein sulfonic acid (FS) permeability and transepithelial electrical resistance (TEER). Lactate dehydrogenase release and ultrastructure were evaluated. Effect of 200 microM eicosapentaenoic acid (EPA, C20:5 n-3), arachidonic acid (AA, C20: 4 n-6), alpha-linoleic acid (ALA, C18: 3 n-3), linoleic acid (LA, C18: 2 n-6), or oleic acid (OA, C18: 1 n-9) enrichment in the culture medium during 24 hours were compared. The effect of the cyclooxygenase inhibitor, indomethacin, lipoxygenase inhibitors, NDGA or AA861, and antioxidant, BHT, was evaluated as a mechanism to change tight junction permeability., Results: Caco-2 cells formed polarized columnar epithelial cells with densely packed microvilli and well developed junctional complexes. Addition of EPA enhanced FS permeability to 3.0+/-1.6-fold and lowered TEER to 0.59+/-1.2-fold vs. control with concentration dependency without cell injury (P<0.01-0.05). OA, AA or LA did not change, but ALA enhanced tight junction permeability. Indomethacin and AA861 normalized the changes mediated by EPA., Conclusions: EPA affects tight junction permeability in intestinal monolayer cells specifically and concentration dependently via cyclooxygenase and lipoxygenase products., (Copyright 2001 Harcourt Publishers Ltd.)

Two cDNAs encoding the splice variants of K(+) channel-interacting protein 2 (KChIP2) recently reported as human KChIP2 have been identified from rat, mouse, and human heart by RT-PCR. A longer variant, KChIP2L encodes a protein of 270 amino acids, which has a 50-amino-acid insertion in N-terminus in comparison with a shorter one, KChIP2S. Interestingly, both KChIP2S and KChIP2L (KChIP2S/L) but not the original KChIP2 were expressed in human heart and umbilical vein endothelial cells (HUVECs). KChIP2S transcripts but not KChIP2L were predominantly expressed in rat, mouse, and human heart and HUVECs, whereas both transcripts were expressed at low levels in other tissues such as brain, aorta, and kidney. Using chimeric proteins of green fluorescence protein (GFP) fused to the N-terminus of KChIP2S/L, the interactions between Kv4.3 and KChIP2S/L were analyzed in native and Kv4.3-expressed HEK293 cells. Specific localization of GFP-fused KChIP2S/L proteins on or near cell membrane was observed only in Kv4.3-expressed HEK293 cells., (Copyright 2001 Academic Press.)

Effects of nifedipine (Nif) and nisoldipine (Nis), dihydropyridine Ca2+ channel blockers (DHPs) on membrane potential and currents of endothelial cells, which are enzymatically dispersed (dis-ECs) from or exist in arterial segments (seg-ECs) of rabbit and rat aorta, were examined. Outward currents induced by 1-10 microM acetylcholine (ACh) in dis-ECs were neither affected by a receptor operated Ca2+ channel blocker, SK&F 96365 (SKF), nor DHPs. ACh hyperpolarized dis-ECs and seg-ECs by 15-20 mV, whereas phenylephrine (Phe) elicited oscillatory depolarization in seg-ECs but not in dis-ECs. The Phe-induced response in seg-ECs was significantly inhibited by treatment with 18beta-glycyrrhetinic acid, a disrupter of gap junctions. Application of 0.3 microM Nif or Nis effectively inhibited the Phe-induced oscillatory depolarization, while these DHPs did not affect ACh-induced hyperpolarization in seg-ECs. The lack of effect on dis-ECs indicates that DHPs have little effect on dis-ECs themselves, nevertheless DHPs inhibit the Phe-induced endothelial potential oscillation which is conducted from smooth muscle cells via a myo-endothelial pathway.

A simple and rapid method is described for the GC-MS determination of 4-nonylphenols (NOs) and 4-tert-octylphenol (OC) in biological samples. The NOs and OC in the sample are extracted with acetonitrile and the lipid in the sample extract is eliminated by partitioning between hexane and acetonitrile. After Florisil PR column clean-up, the sample extract is analyzed by GC-MS in the selected ion monitoring (SIM) mode. Average recoveries in pale chub (fish) and corbicula (shellfish) are 86.0 and 93.4% for NOs, and 95.8 and 96.4% for OC, respectively, spiked at the levels of 1.0 microg of NOs and 0.1 microg of OC per 5 g of fish and shellfish samples. The detection limits are 20 ng/g for NOs and 2 ng/g for OC.

Vascular endothelial cells have several types of Ca2+-dependent K+ current (I(K-Ca)). Here, we describe apamin-sensitive I(K-Ca) which is activated by treatment with histamine (His) in human umbilical vein endothelial cells (HUVECs). In 65 % of HUVECs examined, 100 nM apamin potently inhibited I(K-Ca) and hyperpolarization induced by His (19 and 7 % of control, respectively). In contrast, application of 5 mM tetraethylammonium, a non-selective K channel blocker, or 100 nM iberiotoxin, a selective K channel blocker for a large conductance Ca2+-dependent K+ channel, had small (78 % of control) or no effects (102 % of control) on I(K-Ca), respectively. These findings suggest that apamin-sensitive Ca2+-dependent K+ channels are expressed in HUVECs and activated by receptor stimulation.

In the gastrin and/or cholecystokinin-like immunoreactivity (G/CCK-LI) elution patterns of blood cells in human adults, erythrocyte (RBC) elution pattern has three peaks which are coeluted with gastrin-34 (G34), gastrin-17 (G17) and Vt, and polymorphonuclear leukocyte (PMN) and mononuclear cell (MNC) elution patterns have four peaks which are coeluted with Vo, G34, G17 and Vt. The content of G/CCK-LI in RBC is 1.20 +/- 0.54 f mole/10(8) cells (mean +/- SD). That in PMN and MNC is 1.44 +/- 0.67 p mole/10(8) cells and 1.67 +/- 0.76 p mole/10(8) cells, respectively.

Neurotensin-like immunoreactivity (NTLI) concentrations in the cerebrospinal fluid (CSF) of normal children and patients with febrile aseptic meningitis, aged 7 months to 15 years, were studied. The NTLI concentrations in CSF of 27 children with normal CSF findings were 160.1 +/- 54.6 pg/ml (mean +/- S.D.). The NTLI concentration in CSF of 26 patients in an acute phase of aseptic meningitis was 110.6 +/- 51.1 pg/ml which was significantly (P less than 0.01) lower than the controls. These patients had a mean temperature of 101.4 +/- 1.5 degrees F which remained elevated for an average of 3.5 days. The NTLI concentrations in CSF of 23 patients in a recovery phase (after blood and CSF findings became normal with no fever) were 166.5 +/- 57.8 pg/ml, which did not differ significantly from the normal. There were no statistical correlations between the NTLI concentration in CSF and the protein concentration or total cell count in CSF. These results suggest that NTLI concentration changes during a febrile aseptic meningitis and that it may be associated with thermoregulation.

Neurotensin (NT) is now classified as a brain-gut peptide in the central nervous system and gastrointestinal tract. In the present study, we characterized the NT receptors on the rat liver plasma membranes. The specific binding of [3H]NT was time dependent, reversible, and saturable. Scatchard analysis of the specific binding data yielded two classes of binding sites, a high affinity site and a low affinity site. The average maximum number of binding sites (Bmax) amounted to 13.3 +/- 1.1 fmol/mg protein at high affinity site and 122.3 +/- 21.5 fmol/mg protein at low affinity site, respectively. The dissociation constant (Kd) had values of 0.39 +/- 0.01 nM at high affinity site and 8.1 +/- 1.1 nM at low affinity site, respectively. The amount of specifically bound [3H]NT was significantly reduced in the presence of mono and divalent cations, EDTA, EGTA and a peptidase inhibitor bacitracin, NT1-13 competed with [3H]NT for its binding site with an IC50 of 0.19 nM at high affinity site (0.2 nM concentration of [3H]NT) and 0.7 nM at low affinity site (4.0 nM concentration of [3H]NT). Xenopsin, a NT analogue separated from the skin of Xenopus laevis, was equipotent (IC50 0.75 nM) with NT1-13 at 4.0 nM concentration of [3H]NT. C-terminal sequence of NT contains the structure necessary for interaction with NT binding sites whereas N-terminal sequence had no binding activity. Since NT has a hyperglysemic and a hypercholesterolemic effects in rats, these NT receptors on the rat liver plasma membranes may be involved in the hyperglycemia and/or hypercholesteroremia induced by NT.