The Regulation of Natural Food Dyes Curcumin on the Amyloidogenic Pathway of APP

2013 ◽  
Vol 781-784 ◽  
pp. 1160-1163
Author(s):  
Xiong Zhang ◽  
Jie Yun Sun ◽  
Hong Mei Zhang ◽  
Lu Si ◽  
Yu Li
Keyword(s):  
Time Course ◽  
Mrna Level ◽  
Time Dependent ◽  
Hek293 Cells ◽  
Natural Food ◽  
Inhibition Effect ◽  
Dose Time ◽  
Protein Levels ◽  
Food Dyes

As a promising prevention and therapeutic intervention in Alzheimer’s disease, natural food dyes curcumin could obviously inhibit the generation of Aβ, but the mechanism is not fully defined. This study aims to investigate the effects of curcumin on the amyloidogenic pathway of APP in vitro. Plasmids APPswe and BACE1-mychis were transiently co-transfected into SH-SY5Y and HEK293 cells. Then, they were treated with curcumin at 0, 1.25, 5, 20 μmol/L for 24 h, or with curcumin at 5μmol/L for 0, 12, 24 and 48 h for the time course assay. Our findings showed that curcumin could inhibit the expression of the APP at mRNA level; the expression of the BACE1 and C99 at mRNA and protein levels, furthermore it could inhibit the generation of Aβ40/42, and those changes were dose-time dependent (p<0.05). Our study indicates that Aβ40/42 generation inhibition effect of curcumin might due to its influence on amyloidogenic pathway. This may provide important experimental basis for AD treatment with curcumin.

Trajectory-Based Tissue Engineering for Cartilage Repair: Correlation Between Maturation Rate and Integration Capacity

2013 ◽  
Author(s):  
Matthew B. Fisher ◽  
Nicole Söegaard ◽  
David R. Steinberg ◽  
Robert L. Mauck
Keyword(s):  
Tissue Engineering ◽  
Time Course ◽  
Biomechanical Properties ◽  
Time Dependent ◽  
In Vivo Studies ◽  
Surgical Approaches ◽  
General Hypothesis ◽  
Vitro Assay

Given the limitations of current surgical approaches to treat articular cartilage injuries, tissue engineering (TE) approaches have been aggressively pursued over the past two decades. Although biochemical and biomechanical properties on the order of the native tissue have been achieved (1–5), several in-vitro and in-vivo studies indicate that increased tissue maturity may limit the ability of engineered constructs to remodel and integrate with surrounding cartilage, although results are highly variable (2, 6–8). Thus, “static” measures of construct maturity (e.g. compressive modulus) upon implantation may not be the best indicators of in-vivo success, which likely requires implanted TE constructs to mature, remodel, and integrate with the host over time to achieve optimal results. We recently introduced the concept of “trajectory-based” tissue engineering (TB-TE), which is based on the general hypothesis that time-dependent increases in construct maturation in-vitro prior to implantation (i.e. positive rates) may provide a better predictor of in-vivo success (9). As a first step in evaluating this concept, in the current study we hypothesized that time-dependent increases in equilibrium modulus (a metric of growth) would be correlated to ability of constructs to integrate to cartilage using an in-vitro assay. To test this hypothesis, the current objective was to determine and model the time course of maturation of TE constructs during in-vitro culture and to assess the ability of these constructs to integrate to cartilage at various points during their maturation.

scholarly journals TIMP-2 regulates proliferation, invasion and STAT3-mediated cancer stem cell-dependent chemoresistance in ovarian cancer cells

BMC Cancer ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Ruth M. Escalona ◽  
Maree Bilandzic ◽  
Patrick Western ◽  
Elif Kadife ◽  
George Kannourakis ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cell Lines ◽  
Cancer Progression ◽  
Mrna Level ◽  
Tissue Inhibitors Of Metalloproteinases ◽  
Ovarian Cancer Cells ◽  
Knock Down ◽  
Protein Levels ◽  
Response To Chemotherapy

Abstract Background The metzincin family of metalloproteinases and the tissue inhibitors of metalloproteinases (TIMPs) are essential proteins required for biological processes during cancer progression. This study aimed to determine the role of TIMP-2 in ovarian cancer progression and chemoresistance by reducing TIMP-2 expression in vitro in Fallopian tube secretory epithelial (FT282) and ovarian cancer (JHOS2 and OVCAR4) cell lines. Methods FT282, JHOS2 and OVCAR4 cells were transiently transfected with either single or pooled TIMP-2 siRNAs. The expression of different genes after TIMP-2 knock down (T2-KD) or in response to chemotherapy was determined at the mRNA level by quantitative real time PCR (qRT-PCR) and at the protein level by immunofluorescence. Sensitivity of the cell lines in response to chemotherapy after TIMP-2 knock down was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and 5-Ethynyl-2′-deoxyuridine (EdU) assays. Cell invasion in response to TIMP-2 knockdown was determined by xCELLigence. Results Sixty to 90 % knock down of TIMP-2 expression was confirmed in FT282, OVCAR4 and JHOS2 cell lines at the mRNA and protein levels. TIMP-2 knock down did not change the mRNA expression of TIMP-1 or TIMP-3. However, a significant downregulation of MMP-2 in T2-KD cells occurred at both the protein and activation levels, compared to Control (Cont; scrambled siRNA) and Parental cells (P, transfection reagent only). In contrast, membrane bound MT1-MMP protein levels were significantly upregulated in T2-KD compared to Cont and P cells. T2-KD cells exhibited enhanced proliferation and increased sensitivity to cisplatin and paclitaxel treatments. Enhanced invasion was observed in the T2-KD-JOSH2 and OVCAR4 cells but not in T2-KD-FT282 cells. Treatment with cisplatin or paclitaxel significantly elevated the expression of TIMP-2 in Cont cells but not in T2-KD cells, consistent with significantly elevated expression of chemoresistance and CSC markers and activation of STAT3. Furthermore, a potent inhibitor of STAT3 activation, Momelotinib, suppressed chemotherapy-induced activation of P-STAT3 in OVCAR4 cells with concomitant reductions in the expression of chemoresistance genes and CSC markers. Conclusions The above results suggest that TIMP-2 may have a novel role in ovarian cancer proliferation, invasion and chemoresistance.

scholarly journals A Mammalian Ortholog of Saccharomyces cerevisiae Vac14 That Associates with and Up-Regulates PIKfyve Phosphoinositide 5-Kinase Activity

2004 ◽  
Vol 24 (23) ◽  
pp. 10437-10447 ◽  
Author(s):  
Diego Sbrissa ◽  
Ognian C. Ikonomov ◽  
Jana Strakova ◽  
Rajeswari Dondapati ◽  
Krzysztof Mlak ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Kinase Activity ◽  
Ectopic Expression ◽  
Multivesicular Body ◽  
Hek293 Cells ◽  
Lipid Kinase ◽  
Morphological Alterations ◽  
Protein Levels ◽  
Interfering Rna

ABSTRACT Multivesicular body morphology and size are controlled in part by PtdIns(3,5)P2, produced in mammalian cells by PIKfyve-directed phosphorylation of PtdIns(3)P. Here we identify human Vac14 (hVac14), an evolutionarily conserved protein, present in all eukaryotes but studied principally in yeast thus far, as a novel positive regulator of PIKfyve enzymatic activity. In mammalian cells and tissues, Vac14 is a low-abundance 82-kDa protein, but its endogenous levels could be up-regulated upon ectopic expression of hVac14. PIKfyve and hVac14 largely cofractionated, populated similar intracellular locales, and physically associated. A small-interfering RNA-directed gene-silencing approach to selectively eliminate endogenous hVac14 rendered HEK293 cells susceptible to morphological alterations similar to those observed upon expression of PIKfyve mutants deficient in PtdIns(3,5)P2 production. Largely decreased in vitro PIKfyve kinase activity and unaltered PIKfyve protein levels were detected under these conditions. Conversely, ectopic expression of hVac14 increased the intrinsic PIKfyve lipid kinase activity. Concordantly, intracellular PtdIns(3)P-to-PtdIns(3,5)P2 conversion was perturbed by hVac14 depletion and was elevated upon ectopic expression of hVac14. These data demonstrate a major role of the PIKfyve-associated hVac14 protein in activating PIKfyve and thereby regulating PtdIns(3,5)P2 synthesis and endomembrane homeostasis in mammalian cells.

scholarly journals Enhanced Cerebral Expression of MCT1 and MCT2 in a Rat Ischemia Model Occurs in Activated Microglial Cells

2009 ◽  
Vol 29 (7) ◽  
pp. 1273-1283 ◽  
Author(s):  
Tiago JTP Moreira ◽  
Karin Pierre ◽  
Fumihiko Maekawa ◽  
Cendrine Repond ◽  
Aleta Cebere ◽  
...  
Keyword(s):  
Protein Expression ◽  
Mrna Level ◽  
Protein Levels ◽  
Microglial Cell Line ◽  
Tnf Α ◽  
Ischemic Episode ◽  
Isolectin B4 ◽  
Factor Α ◽  
Necrosis Factor

Monocarboxylate transporters (MCTs) are essential for the use of lactate, an energy substrate known to be overproduced in brain during an ischemic episode. The expression of MCT1 and MCT2 was investigated at 48 h of reperfusion from focal ischemia induced by unilateral extradural compression in Wistar rats. Increased MCT1 mRNA expression was detected in the injured cortex and hippocampus of compressed animals compared to sham controls. In the contralateral, uncompressed hemisphere, increases in MCT1 mRNA level in the cortex and MCT2 mRNA level in the hippocampus were noted. Interestingly, strong MCT1 and MCT2 protein expression was found in peri-lesional macrophages/microglia and in an isolectin B4+/S100β+ cell population in the corpus callosum. In vitro, MCT1 and MCT2 protein expression was observed in the N11 microglial cell line, whereas an enhancement of MCT1 expression by tumor necrosis factor-α (TNF-α) was shown in these cells. Modulation of MCT expression in microglia suggests that these transporters may help sustain microglial functions during recovery from focal brain ischemia. Overall, our study indicates that changes in MCT expression around and also away from the ischemic area, both at the mRNA and protein levels, are a part of the metabolic adaptations taking place in the brain after ischemia.

High Glucose/Thrombin-Induced Endothelial Inflammation Via Microrna-146a and Nox4 Regulation

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 5952-5952
Author(s):  
Ching-Tien Peng ◽  
Wan Yu Lo ◽  
Huang Joe Wang
Keyword(s):  
High Glucose ◽  
Conflicts Of Interest ◽  
Mrna Level ◽  
In Silico Analysis ◽  
Fold Increase ◽  
Ros Generation ◽  
Aortic Endothelial Cells ◽  
Protein Levels ◽  
Endothelial Inflammation

Abstract Diabetes is associated with hyperglycemia and increased thrombin generation. It is unknown whether high glucose (HG)/thrombin can modulate the expression of NAPDH oxidase (Nox) subtypes in human aortic endothelial cells (HAECs). Besides, we investigate whether miR-146a is involved in endothelial cell inflammation. We observed that HG (25 mmol/l) exerted a synergistic effect with thrombin (2 U/ml) for induction of Nox4 mRNA level in HAECs. The increased Nox4 mRNA was associated with increased Nox4 protein and ROS production. We also demonstrated that HG/thrombin treatment increased interleukin-8 and interleukin-6 protein levels. Besides, HG/thrombin treatment caused an 11.43-fold increase of THP-1 adhesion to HAECs. In Silico analysis identified homology between miR-146a and the 3’-UTR of the human Nox4 mRNA, suggesting a potential regulation of Nox4 by miR-146a. Furthermore, HG/thrombin treatment decreased miR146a expression to 58% of the control, indicating an impaired feedback restrain of HG/thrombin-induced endothelial inflammation. MiR-146a mimic transfection prevented HG/thrombin-induced upregulation of Nox4 mRNA, Nox4 protein, and ROS generation. In addition, inflammatory phenotypes were attenuated in miR-146a mimic-transfected HAECs. In conclusion, miR-146a is involved in the regulation of endothelial inflammation via modulation of Nox4 in an in-vitro milieu mimicking diabetic atherothrombosis. Disclosures No relevant conflicts of interest to declare.

Time course of inflammatory and remodeling events in a murine model of asthma: effect of steroid treatment

2000 ◽  
Vol 279 (6) ◽  
pp. L1120-L1128 ◽  
Author(s):  
Alexandre Trifilieff ◽  
Ahmed El-Hashim ◽  
Claude Bertrand
Keyword(s):  
Time Course ◽  
Histological Analysis ◽  
Steroid Treatment ◽  
Airway Hyperreactivity ◽  
Time Dependent ◽  
Epithelial Cell Proliferation ◽  
Alveolar Cells ◽  
Protein Levels ◽  
Kinetics Of ◽  
Cellular Fibronectin

The kinetics of airway inflammation and remodeling processes following ovalbumin aerosol challenge in sensitized BALB/c mice was studied. Mice were exposed to either single or five ovalbumin challenges over 5 days. In both protocols, time-dependent increases in bronchoalveolar lavage (BAL) cellular fibronectin, neutrophils and eosinophils were observed. The kinetics of these events were similar in both protocols; however, the magnitude of the response was much greater following repeated challenges. BAL protein levels and lymphocyte numbers were increased only following repeated challenges, whereas interleukin (IL)-5 and IL-4 were increased in both protocols. Histological analysis revealed a time-dependent increase in epithelial cell proliferation and in mucus-producing epithelial cells. Proliferation of alveolar cells was observed only following repeated challenges. Airway hyperreactivity was observed in both protocols but was much greater following repeated challenges. Pretreatment with dexamethasone fully inhibited the inflammatory response and airway hyperreactivity but only partially inhibited the remodeling process. These data suggest that glucocorticoids, although potent anti-inflammatory agents, may not be potent in reducing the lung remodeling process associated with asthma.

scholarly journals Overexpression of DDR1 Promotes Migration, Invasion, Though EMT-Related Molecule Expression and COL4A1/DDR1/MMP-2 Signaling Axis

2020 ◽  
Vol 19 ◽  
pp. 153303382097327
Author(s):  
Xin Xie ◽  
Hongchao He ◽  
Ning Zhang ◽  
Xiaojing Wang ◽  
Wenbin Rui ◽  
...  
Keyword(s):  
Tyrosine Kinases ◽  
Molecular Mechanisms ◽  
Mrna Level ◽  
Migration And Invasion ◽  
Rt Pcr ◽  
Protein Levels ◽  
Signaling Axis ◽  
Slug Expression ◽  
Mrna And Protein Expression

Purpose: Discoidin domain receptor 1 (DDR1) belongs to a novel class of receptor tyrosine kinases. Previous evidence indicates that DDR1 overexpression promotes the aggressive growth of bladder cancer (BC) cells. This study aimed to investigate the molecular mechanisms by which DDR1 influences BC. Methods: DDR1 was transfected into human BC RT4 cells. DDR1, COL4A1, and MMP-2 expression in 30 BC tissues and paired adjacent tissues were examined by real-time polymerase chain reaction (RT-PCR) and immunohistochemistry. Transwell assays were conducted to determine cell migration and invasion. RT-PCR and western blot (WB) were also used to measure the DDR1, COL4A1, MMP-2, and EMT-related gene (ZEB1 and SLUG) expression in RT4 cells after DDR1 overexpression. Results: COL4A1 and MMP-2 interacted with DDR1 in the PPI network. RT-PCR and immunohistochemistry results showed that both mRNA and protein levels of DDR1 and COL4A1 were significantly increased in BC tissue, while the expression of MMP-2 was increased only at the mRNA level ( P < 0.05). Overexpression of DDR1 in RT4 cells significantly promoted their migratory and invasive capabilities in vitro ( P < 0.05). Moreover, overexpression of DDR1 in RT4 cells increased the mRNA and protein expression of ZEB1, SLUG, COL4A1, and MMP-2 ( P < 0.01). DDR1-mediated migration and invasion of RT4 cells were reversed after COL4A1-siRNA treatment. Conclusion: DDR1 may be a potential therapeutic target in BC patients.

Effect of external Ca2+ concentration on stretch-augmented natriuretic peptide secretion by rat atria

1991 ◽  
Vol 260 (4) ◽  
pp. C756-C762 ◽  
Author(s):  
E. Page ◽  
J. Upshaw-Earley ◽  
G. E. Goings ◽  
D. A. Hanck
Keyword(s):  
Sarcoplasmic Reticulum ◽  
Natriuretic Peptide ◽  
Time Course ◽  
Rate Coefficient ◽  
Time Dependent ◽  
Dependent Manner ◽  
Dependent Inactivation ◽  
Long Time ◽  
Peptide Secretion

An in vitro noncontracting rat atrial preparation stretched at 37 degrees C by a distending pressure of 5.1 mmHg was used to examine effects of external Ca2+ concentration ([Ca2+]out, 0.05-3.0 mM) on secretion of immunoreactive atrial natriuretic peptide (ANP) in presence of saxitoxin (STX) and in presence or absence of ryanodine. Under these conditions, the time course of the amount (y) of ANP secreted per milligram dry atrium during 44 min could be approximated by a rate coefficient (k) according to the relation y = s[1 - e(-kt)], where s is the maximal amount secreted after a long time (t). Although k, the rate coefficient for stretch-augmented secretion, increased significantly as [Ca2+]out was raised, secretion inactivated progressively in a time- and [Ca2+]out-dependent manner. This time-dependent decrease was not prevented by ryanodine. We conclude that a component of ANP secreted by quiescent atria in vitro is positively modulated by [Ca2+]out and does not require ryanodine-sensitive Ca2+ release from sarcoplasmic reticulum. The [Ca2+]out-sensitive processes underlying time-dependent inactivation of secretion remain undetermined.

scholarly journals Transient Transcriptional Activation of theVibrio cholerae El Tor Virulence Regulator ToxT in Response to Culture Conditions

1999 ◽  
Vol 67 (5) ◽  
pp. 2178-2183 ◽  
Author(s):  
Ana I. Medrano ◽  
Victor J. DiRita ◽  
Gabriela Castillo ◽  
Joaquin Sanchez
Keyword(s):  
Transcriptional Activation ◽  
Time Course ◽  
Growth Period ◽  
Culture Conditions ◽  
Primer Extension ◽  
Protein Levels ◽  
Reverse Transcription Pcr ◽  
Transient Activation ◽  
El Tor

ABSTRACT Vibrio cholerae El Tor require special in vitro culture conditions, consisting of an initial static growth period followed by shift to shaking (AKI conditions), for expression of cholera toxin (CT) and toxin coregulated pili (TCP). ToxT, a regulator whose initial transcription depends on the ToxR regulator, positively modulates expression of CT and TCP. To help understand control of CT and TCP in El Tor vibrios, we monitored ctxAB and ToxR-dependenttoxT transcription by time course primer extension assays. AKI conditions stimulated CT synthesis with an absence ofctxAB transcription during static growth followed by induction upon shaking. ToxR-dependent toxT transcription was induced at the end of the static growth period but was transient, stopping shortly after shaking was initiated but, interestingly, also if the static phase was prolonged. Immunoblot assays showed that ToxR protein levels were not coincidentally transient, implying a protein on/off switch mechanism for ToxR. Despite the transient activation by ToxR, transcription of ctxAB was maintained during shaking. This finding suggested continued toxT expression, possibly through relay transcription from another promoter. The 12.6-kb distant upstream tcpA promoter responsible for expression of the TCP operon has been proposed to provide an alternate toxTmessage by readthrough transcription. Activation of thetcpA promoter is supported by increased expression of TcpA protein during the shaking phase of the culture. Readthrough transcription of toxT from tcpA would be compatible with reverse transcription-PCR evidence for atoxT mRNA at times when ToxR-dependent transcription was no longer detectable by primer extension.

scholarly journals The inhibition effect of crude juice of olive Olea europeae on cancer cell line Rhabdomyosarcoma (RD)

2014 ◽  
Vol 11 (2) ◽  
pp. 962-968
Author(s):  
Baghdad Science Journal
Keyword(s):  
Cell Line ◽  
Cancer Cell ◽  
Fruit Juice ◽  
Cancer Cell Line ◽  
High Concentration ◽  
Inhibition Effect ◽  
Dose Time ◽  
Black Olive ◽  
Titration System

The inhibition effect of crude juice of green and black olive on cancer cell line (RD) in vitro has been studied by depending on micro titration system . Eleven different concentration starting from (916-960) mg/ml of crude juice respectively ,for three periods of exposure(24-48-72)hours. The resulted showed that the inhibition effect dependent on type of olive fruit juice ,concentration of dose ,time of exposure and the high concentration of both type of olive juice increased the growth of cell line while other concentration caused decrease in different rates ,moreover the black juice was more effective than green and 48 hours' time exposure was the best for inhibition.

Sign in / Sign up

Export Citation Format

Share Document