Effect Invitro Research Articles

Nucleolin inhibitor GroA triggers reduction in epidermal growth factor receptor activation: Pharmacological implication for glial scarring after spinal cord injury.

Glial scarring, formed by reactive astrocytes, is one of the major impediments for regeneration after spinal cord injury (SCI). Reactive astrocytes become hypertrophic, proliferate and secrete chondroitin sulphate proteoglycans into the extracellular matrix (ECM). Many studies have demonstrated that epidermal growth factor receptors (EGFR) can mediate astrocyte reactivity after neurotrauma. Previously we showed that there is crosstalk between nucleolin and EGFR that leads to increased EGFR activation followed by increased cell proliferation. Treatment with the nucleolin inhibitor GroA (AS1411) prevented these effects invitro and invivo. In this study, we hypothesized that similar interactions may mediate astrogliosis after SCI. Our results demonstrate that nucleolin and EGFR interaction may play a pivotal role in mediating astrocyte proliferation and reactivity after SCI. Moreover, we demonstrate that treatment with GroA reduces EGFR activation, astrocyte proliferation and chondroitin sulphate proteoglycans secretion, therefore promoting axonal regeneration and sprouting into the lesion site. Our results identify, for the first time, a role for the interaction between nucleolin and EGFR in astrocytes after SCI, indicating that nucleolin inhibitor GroA may be used as a novel treatment after neurotrauma. A major barrier for axonal regeneration after spinal cord injury is glial scar created by reactive and proliferating astrocytes. EGFR mediate astrocyte reactivity. We showed that inhibition of nucleolin by GroA, reduces EGFR activation, which results in attenuation of astrocyte reactivity and proliferation invivo and invitro. EGFR, epidermal growth factor receptor.

Component of Caramel Food Coloring, THI, Causes Lymphopenia Indirectly via a Key Metabolic Intermediate

Caramel color is widely used in the food industry, and its many variations are generally considered to be safe. It has been known for a long time that THI (2-acetyl-4-(tetrahydroxybutyl)imidazole), a component of caramel color III, causes lymphopenia in animals through sphingosine 1-phosphate (S1P) lyase (S1PL) inhibition. However, this mechanism of action has not been fully validated because THI does not inhibit S1PL invitro. To reconcile this situation, we examined molecular details of THI mechanism of action using "smaller" THI derivatives. We identified a bioactive derivative, A6770, which has the same lymphopenic effect as THI via S1PL inhibition. In the case of A6770 we observe this effect both invitro and invivo, and demonstrate that A6770 is phosphorylated and inhibits S1PL in the same way as 4-deoxypyridoxine. In addition, A6770 was detected in rat plasma following oral administration of THI, suggesting that A6770 is a key metabolic intermediate of THI.

Salinomycin inhibits the growth of colorectal carcinoma by targeting tumor stem cells.

Salinomycin is a monocarboxylic polyether antibiotic that has been reported to induce apoptosis in various types of cancer cells with specificity for cancer stem cells. However, its anticancer effect in colorectal cancer stem cells has never been reported. In the present study, we examined the ability of salinomycin to induce cell death in the colorectal cancer stem cell line CD44+EpCAM+HCT-116, and we measured its invivo tumor inhibition capacity. Salinomycin dose-dependently induced cytotoxicity in the CD44+EpCAM+HCT-116cells and inhibited colony formation. Salinomycin treatment was shown to induce apoptosis, as evidenced by nuclear fragmentation, an increase in the proportion of acridine orange/ethidium bromide-positive cells and an increase in the percentage of AnnexinV-positive cells. Apoptosis was induced in colorectal cancer stem cells in a caspase-dependent manner, as shown by an increase in the levels of cleaved caspase-3,-8 and-9. JC-1 staining further revealed that salinomycin induced colorectal cancer cell apoptosis via the mitochondrial pathway. In addition, salinomycin treatment of xenograft mice inhibited the growth of tumors derived from the CD44+EpCAM+HCT-116cells. The present study demonstrated that the antibiotic salinomycin exerts an anti-colorectal cancer effect invitro and invivo, suggesting salinomycin as a potential drug for colorectal cancer therapy.

MP66-17 MICRORNA-224 IS DOWN-REGULATED IN PROSTATE CANCER AND MEDIATES TUMOR-SUPPRESSIVE EFFECTS IN VITRO

You have accessJournal of UrologyProstate Cancer: Basic Research V1 Apr 2015MP66-17 MICRORNA-224 IS DOWN-REGULATED IN PROSTATE CANCER AND MEDIATES TUMOR-SUPPRESSIVE EFFECTS IN VITRO Felix Bienert, Kati Erdmann, Susanne Fuessel, and Manfred P. Wirth Felix BienertFelix Bienert More articles by this author , Kati ErdmannKati Erdmann More articles by this author , Susanne FuesselSusanne Fuessel More articles by this author , and Manfred P. WirthManfred P. Wirth More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.2370AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The microRNA miR-224 is a putative regulator of alpha-methylacyl-CoA racemase (AMACR) which is known to be up-regulated in prostate cancer (PCa). Here, we analyzed the expression levels of miR-224 and its host gene gamma-aminobutyric acid A receptor / epsilon subunit (GABRE). The functional role of miR-224 was then investigated in vitro. METHODS Expression levels were analyzed by qPCR using 50 malignant (PCa) and matched non-malignant tissue samples from prostatectomy explants as well as 30 samples derived from patients with benign prostatic hyperplasia (BPH). AMACR expression data were used from a previous study on the same sample cohort. DU145, PC-3 and LNCaP PCa cells were transfected with 100 nM of miR-224 mimic or a control construct for 4 h. Protein and mRNA expression levels of AMACR as well as functional analyses (viability, proliferation, cell colony formation, apoptosis) were conducted 48 h after transfection. RESULTS The expression of miR-224 was significantly decreased in PCa tissue samples by 3.5- and 2.7-fold compared to matched non-malignant and BPH tissue samples, respectively. Concomitantly, GABRE mRNA expression was completely down-regulated compared to either control group. The down-regulation of miR-224 significantly correlated with the down-regulation of its host gene GABRE (Spearman correlation coefficient: 0.442) as well as with the previously determined up-regulation of its target gene AMACR (Spearman correlation coefficient: 0.384). In vitro, miR-224 led to slight decreases of AMACR mRNA by 30% and protein by 20% only in PC-3 cells. MiR-224 marginally influenced cellular viability and proliferation in DU145 and LNCaP cells. In contrast, miR-224-treated PC-3 cells displayed a decrease in viability by 17% and proliferation by 34% compared to control. Cell colony formation was inhibited in both DU145 and PC-3 cells by 23% and 42%, respectively, following miR-224 administration. Furthermore, miR-224 produced a doubling of apoptosis-mediated cell death rate in PC-3 cells, whereas apoptosis rate remained unaffected in DU145 and LNCaP cells. CONCLUSIONS Our findings indicate that the PCa-specific down-regulation of miR-224 correlates with the down-regulation of its host gene GABRE as well as with the up-regulation of its putative target gene AMACR. Depending on the cell line miR-224 could inhibit tumor cell viability and growth as well as induce apoptosis-mediated cell death which suggests a tumor-suppressive role for this microRNA in PCa. © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e822 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Felix Bienert More articles by this author Kati Erdmann More articles by this author Susanne Fuessel More articles by this author Manfred P. Wirth More articles by this author Expand All Advertisement Advertisement PDF DownloadLoading ...

Die Rolle neuer „pro-resolving” Lipidmediatoren bei entzündlichen Lungenerkrankungen

Uncontrolled inflammation of the lung contributes to the major medical and economic burden on healthcare, and the need for therapeutics to dampen pathological inflammation is largely unmet. Recently, a new genus of anti-inflammatory/ pro-resolving lipid mediators has been identified: Lipoxins, resolvins, protectins and maresins. These compounds are enzymatically derived from the polyunsaturated fatty acids (PUFAs) arachidonic acid (AA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) that have long been known to have beneficial health properties. These mediators have potent anti-inflammatory effects IN VITRO and IN VIVO in murine models of lung inflammation. Therefore, this group of compounds carries considerable therapeutic potential for the treatment of many inflammatory lung diseases including asthma, cystic fibrosis and acute lung injury.

AntibactERial Activity of Four Cephalosporins in an ExpERimental Infection in Relation to In Vitro Effect and Pharmacokinetics

The in vitro activity of four cephalosporins was compared with their effects in an experimental thigh infection (cefuroxime and cefamandole against Escherichia coli and cefamandole, ceftriaxone, and ceftazidime against Klebsiella pneumoniae) in granulocytopenic mice. The effect in vitro (ER) was defined as the difference between the growth rate without antibiotic and the growth rate at the steepest part of a 3-h growth curve in the presence of an antibiotic. The relation between concentration and ER was described with the Hill equation. Using pharmacokinetic parameters of the plasma concentrations in vivo and those of the Hill equation the corresponding time course of ER was calculated and by integration with respect to time (0tERdt), an estimate was obtained of the effect on bacteria. For all four antibiotics this estimate was significantly correlated with the actual values of the effect in vivo (EN), defined as the difference in numbers of bacteria between controls and antibiotic-treated animals at 4 h.

ANTIMICROBIAL EFFECT IN VITRO OF THE ASCORBIC ACID OXIDATION

Acta Pathologica Microbiologica ScandinavicaVolume 37, Issue 6 p. 493-506 ANTIMICROBIAL EFFECT IN VITRO OF THE ASCORBIC ACID OXIDATION I. Effect on Bacteria, Fungi and Viruses in Pure Cultures Y. ERICSSON, Y. ERICSSON STATE DENTAL SCHOOL AND THE STATE BACTERIOLOGICAL LABORATORY, STOCKHOLMSearch for more papers by this authorH. LUNDBECK, H. LUNDBECK STATE DENTAL SCHOOL AND THE STATE BACTERIOLOGICAL LABORATORY, STOCKHOLMSearch for more papers by this author Y. ERICSSON, Y. ERICSSON STATE DENTAL SCHOOL AND THE STATE BACTERIOLOGICAL LABORATORY, STOCKHOLMSearch for more papers by this authorH. LUNDBECK, H. LUNDBECK STATE DENTAL SCHOOL AND THE STATE BACTERIOLOGICAL LABORATORY, STOCKHOLMSearch for more papers by this author First published: September 1955 https://doi.org/10.1111/j.1699-0463.1955.tb00975.xCitations: 31AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume37, Issue6September 1955Pages 493-506 RelatedInformation