Murine CD14 gene expression in vivo: extramyeloid synthesis and regulation by lipopolysaccharide.

A murine model system was used to study the distribution and regulation of CD14 gene expression in vivo. Western blot analysis failed to detect CD14 in plasma from untreated CB6 (BALB/c x C57Bl6) mice, but showed markedly increased levels of CD14 in plasma from mice treated with lipopolysaccharide (LPS). Plasma levels of CD14 increased in a time- and dose-dependent manner, reaching a maximum between 8 and 16 h. Northern blot analysis of total RNA extracted from mouse tissues revealed low, but significant, levels of CD14 mRNA in many tissues of untreated animals with the highest levels in uterus, adipose tissue, and lung. After intraperitoneal injection of LPS, induction of CD14 gene expression was detected in all organs examined with the extent of induction varying between organs. Induction of CD14 mRNA was both time and dose dependent. Maximum induction in the heart and lung was observed 2-4 h after injection of LPS, while liver and kidney showed maximal induction between 8 and 16 h. In situ hybridization showed that CD14 mRNA was expressed in myeloid cells in many tissues, and that expression in these cells was upregulated by LPS. Unexpectedly, CD14 mRNA was also detected in other cells within tissues, including epithelial cells, and expression in these cell types also was upregulated by LPS. Immunochemical analysis revealed that CD14 antigen colocalized to the cytoplasm of cells expressing CD14 mRNA. These studies demonstrate that CD14 gene expression is not restricted to myeloid cells, and that the level of expression of CD14 is influenced by exposure to LPS.

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AV-65, a Novel Inhibitor of the Wnt/β-Catenin Signaling Pathway, Inhibits the Proliferation of Myeloma Cells.

Blood ◽

10.1182/blood.v114.22.2866.2866 ◽

2009 ◽

Vol 114 (22) ◽

pp. 2866-2866

Author(s):

Hisayuki Yao ◽

Eishi Ashihara ◽

Rina Nagao ◽

Shinya Kimura ◽

Hideyo Hirai ◽

...

Keyword(s):

Gene Expression ◽

Mouse Model ◽

Signaling Pathway ◽

Small Molecule ◽

Conflicts Of Interest ◽

Flow Cytometric Analysis ◽

Cancer Cell Line ◽

Dependent Manner ◽

Dose Dependent

Abstract Abstract 2866 Poster Board II-842 Although new molecular targeting agents against multiple myeloma (MM) have been developed, MM still remains an incurable disease. It is important to continue to investigate new therapeutic agents based on the biology of MM cells. β-catenin is the downstream effector of Wnt signaling and it regulates genes implicated in malignant progression. We have demonstrated that blockade of Wnt/β-catenin signaling pathway inhibits the progression of MM by using RNA interference methods with an in vivo mouse model (Ashihara E, et al. Clin Cancer Res 15:2731, 2009.). In this study, we investigated the effects of AV-65, a novel inhibitor of the Wnt/β-catenin signaling pathway, on MM cells. The system to identify a series of small molecule compounds using a biomarker driven approach has been established. A gene expression biomarker signature reporting on the inhibition of Wnt/β-catenin signaling was generated upon treatment of a colon cancer cell line with β-catenin siRNA. This gene expression signatiure was used to screen a small molecule compound library to identify compounds which mimic knockdown of β-catenin and thus potentially inhibit the Wnt/β-catenin signaling pathway. One compound series, LC-363, was discovered from this screen and validated as novel Wnt/β-catenin signaling inhibitors (Strovel JW, et al. ASH meeting, 2007.). We investigated the inhibitory effects of AV-65, one of LC-363 compounds, on MM cell proliferation. AV-65 inhibited the proliferation of MM cells in a time- and a dose-dependent manner and the values of IC50 at 72 hrs were ranging from 11.7 to 82.1 nM. AV-65 also showed an inhibitory effect on the proliferation of RPMI8226/LR-5 melphalan-resistant MM cells (provided from Dr. William S. Dalton). In flow cytometric analysis, apoptotic cells were increased by AV-65 treatment in a time- and a dose-dependent manner. Western blotting analysis showed that β-catenin was ubiquitinated and that the expression of nuclear β-catenin diminished (Figure 1). Moreover, AV-65 suppressed T-cell factor transcriptional activities, resulting in the decrease of c-myc expression. Taken together, AV-65 promotes the degradation of β-catenin, resulting in the induction of apoptosis of MM cells. We next investigated the in vivo effects of AV-65 using an orthotopic MM-bearing mouse model. AV-65 inhibits the growth of MM cells and significantly prolongs the survival rates (Figure 2). In conclusion, AV-65 inhibited the proliferation of MM cells via inhibition of the Wnt/β-catenin signaling pathway. AV-65 is a promising therapeutic agent for treatment of MM. Disclosures: No relevant conflicts of interest to declare.

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Stimulation of incretin secretion by dietary lipid: is it dose dependent?

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.90601.2008 ◽

2009 ◽

Vol 297 (2) ◽

pp. G299-G305 ◽

Cited By ~ 52

Author(s):

Stephanie M. Yoder ◽

Qing Yang ◽

Tammy L. Kindel ◽

Patrick Tso

Keyword(s):

Lipid Content ◽

Cell Types ◽

Distal Portion ◽

Dietary Lipid ◽

Dependent Manner ◽

Incretin Hormones ◽

Sprague Dawley ◽

Dependent Relationship ◽

Dose Dependent

After the ingestion of nutrients, secretion of the incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) by the enteroendocrine cells increases rapidly. Previous studies have shown that oral ingestion of fat stimulates secretion of both incretins; however, it is unclear whether there is a dose-dependent relationship between the amount of lipid ingested and the secretion of the hormones in vivo. Recently, we found a higher concentration of the incretin hormones in intestinal lymph than in peripheral or portal plasma. We therefore used the lymph fistula rat model to test for a dose-dependent relationship between the secretion of GIP and GLP-1 and dietary lipid. Under isoflurane anesthesia, the major mesenteric lymphatic duct of male Sprague-Dawley rats was cannulated. Each animal received a single, intraduodenal bolus of saline or varying amounts of the fat emulsion Liposyn II (0.275, 0.55, 1.1, 2.2, and 4.4 kcal). Lymph was continuously collected for 3 h and analyzed for triglyceride, GIP, and GLP-1 content. In response to increasing lipid calories, secretion of triglyceride, GIP, and GLP-1 into lymph increased dose dependently. Interestingly, the response to changes in intraluminal lipid content was greater in GLP-1- than in GIP-secreting cells. The different sensitivities of the two cell types to changes in intestinal lipid support the concept that separate mechanisms may underlie lipid-induced GIP and GLP-1 secretion. Furthermore, we speculate that the increased sensitivity of GLP-1 to intestinal lipid content reflects the hormone's role in the ileal brake reflex. As lipid reaches the distal portion of the gut, GLP-1 is secreted in a dose-dependent manner to reduce intestinal motility and enhance proximal fat absorption.

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Lipoprotein lipase stimulates the binding and uptake of moderately oxidized low-density lipoprotein by J774 macrophages

Biochemical Journal ◽

10.1042/bj3140563 ◽

1996 ◽

Vol 314 (2) ◽

pp. 563-568 ◽

Cited By ~ 35

Author(s):

Wendy L. HENDRIKS ◽

Hans van der BOOM ◽

Leonie C. van VARK ◽

Louis M. HAVEKES

Keyword(s):

Lipoprotein Lipase ◽

Oxidized Ldl ◽

Low Density Lipoprotein ◽

Heparan Sulphate ◽

Density Lipoprotein ◽

Cell Types ◽

Low Density ◽

Dependent Manner ◽

Dose Dependent

Lipoprotein lipase (LPL) stimulates the uptake of low-density lipoprotein (LDL) and very-low-density lipoprotein (VLDL) in different cell types, including macrophages, through bridging of LPL between lipoproteins and extracellular heparan sulphate proteoglycans (HSPG). Because macrophages produce LPL and because modified lipoproteins are present in the arterial wall in vivo, we wondered whether LPL also enhances the uptake of oxidized LDL by J774 macrophages. LDL samples with different degrees of oxidation, as evaluated by relative electrophoretic mobility (REM) as compared with native LDL are used, as well as native and acetylated LDL. Addition of 5 μg/ml LPL to the J774 cell culture medium stimulated the binding of both native LDL and moderately oxidized LDL (REM < 3.5) 50–100-fold, and their uptake was stimulated approx. 20-fold. The LPL-mediated binding of native LDL and moderately oxidized LDL was dose-dependent. Preincubation of the cells with heparinase (2.4 units/ml) inhibited the stimulatory effect of LPL, indicating that this LPL-mediated stimulation was due to bridging between the lipoproteins and HSPG. The binding to J774 macrophages of severely oxidized LDL (REM = 4.3) was stimulated less than 3-fold by LPL, whereas its uptake was not stimulated significantly. The binding and uptake of acetylated LDL (AcLDL) were not stimulated by LPL, although the LPL-molecule itself does bind to AcLDL. Measurements of the cellular lipid content showed that addition of LPL also stimulated the accumulation in the cells of cholesteryl ester derived from both native LDL and moderately oxidized LDL in a dose-dependent manner. We conclude that our results present experimental evidence for the hypothesis that LPL serves as an atherogenic component in the vessel wall.

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Macrophage inflammatory and regenerative response periodicity is programmed by cell cycle and chromatin state

10.1101/2021.06.24.449850 ◽

2021 ◽

Author(s):

Bence Daniel ◽

Julia A. Belk ◽

Stefanie L. Meier ◽

Andy Y. Chen ◽

Katalin Sandor ◽

...

Keyword(s):

Gene Expression ◽

Cell Cycle ◽

Phase Distribution ◽

Immunological Response ◽

Cell Types ◽

Interleukin 4 ◽

Dependent Manner ◽

M Phase ◽

Fundamental Biological Process

Cell cycle (CC) is a fundamental biological process with robust, cyclical gene expression programs to facilitate cell division. In the immune system, a productive immune response requires the expansion of pathogen-responsive cell types, but whether CC also confers unique gene expression programs that inform the subsequent immunological response remains unclear. Here we demonstrate that single macrophages adopt different plasticity states in CC, which is a major source of heterogeneity in response to polarizing cytokines. Specifically, macrophage plasticity to interferon gamma (IFNG) is substantially reduced, while interleukin 4 (IL-4) can induce S-G2/M-biased gene expression. Additionally, IL-4 polarization shifts the CC-phase distribution of the population towards G2/M phase, providing a mechanism for reduced IFNG-induced repolarization. Finally, we show that macrophages express tissue remodeling genes in the S-G2/M-phases of CC, that can be also detected in vivo during muscle regeneration. Therefore, macrophage inflammatory and regenerative responses are gated by CC in a cyclical phase-dependent manner.

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Semaphorin 3A Inhibits Inflammation in Chondrocytes under Excessive Mechanical Stress

Mediators of Inflammation ◽

10.1155/2018/5703651 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 13

Author(s):

Chikako Sumi ◽

Naoto Hirose ◽

Makoto Yanoshita ◽

Mami Takano ◽

Sayuri Nishiyama ◽

...

Keyword(s):

Gene Expression ◽

Western Blot ◽

Mechanical Stress ◽

Inflammatory Cytokines ◽

Blot Analysis ◽

Western Blot Analysis ◽

Dependent Manner ◽

Semaphorin 3A ◽

Neuropilin 1 ◽

Dose Dependent

Background. Excessive mechanical stress causes inflammation and destruction of cartilage and is considered one of the cause of osteoarthritis (OA). Expression of semaphorin 3A (Sema3A), which is an axon guidance molecule, has been confirmed in chondrocytes. However, there are few reports about Sema3A in chondrocytes, and the effects of Sema3A on inflammation in the cartilage are poorly understood. The aim of this study was to examine the role of Sema3A in inflammation caused by high magnitude cyclic tensile strain (CTS). Methods. Expression of Sema3A and its receptors neuropilin-1 (NRP-1) and plexin-A1 (PLXA1) in ATDC5 cells was examined by Western blot analysis. ATDC5 cells were subjected to CTS of 0.5 Hz, 10% elongation with added Sema3A for 3 h. Gene expression of IL-1β, TNF-ɑ, COX-2, MMP-3, and MMP-13 was examined by qPCR analysis. Furthermore, the phosphorylation of AKT, ERK, and NF-κB was detected by Western blot analysis. Results. Added Sema3A inhibited the gene expression of inflammatory cytokines upregulated by CTS in a dose-dependent manner. Addition of Sema3A suppressed the activation of AKT, ERK, and NF-κB in a dose-dependent manner. Conclusions. Sema3A reduces the gene expression of inflammatory cytokines by downregulating the activation of AKT, ERK, and NF-κB pathways in ATDC5 cells under CTS.

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Imperatorin Suppresses Anaphylactic Reaction and IgE-Mediated Allergic Responses by Inhibiting Multiple Steps of FceRI Signaling in Mast Cells: IMP Alleviates Allergic Responses in PCA

BioMed Research International ◽

10.1155/2019/7823761 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 8

Author(s):

Zhemin Xian ◽

Guangyu Jin ◽

Hongmei Li ◽

Jingzhi Jiang ◽

Chongyang Wang ◽

...

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Western Blot ◽

Proinflammatory Cytokines ◽

Blot Analysis ◽

Dependent Manner ◽

Ige Mediated ◽

Dose Dependent

This study is to investigate the effects of imperatorin (IMP) on allergic responses mediated by mast cells, both in vitro and in vivo. Passive cutaneous anaphylaxis (PCA) model was established. Histological detection was performed to assess the ear histology. ELISA and Western blot analysis were used to detect the levels of corresponding cytokines and signalling pathway proteins. IMP decreased the leakage of Evans blue and the ear thickness in the PCA models, in a dose-dependent manner, and alleviated the degranulation of mast cells. Moreover, IMP reduced the expression of TNF-α, IL-4, IL-1β, IL-8, and IL-13. Furthermore, IMP inhibited the phosphorylation levels of Syk, Lyn, PLC-γ1, and Gab2, as well as the downstream MAPK, PI3K/AKT, and NF-κB signaling pathways. In addition, IMP inhibited the mast cell-mediated allergic responses through the Nrf2/HO-1 pathway. IMP attenuates the allergic responses through inhibiting the degranulation and decreasing the expression levels of proinflammatory cytokines in the mast cells, involving the PI3K/Akt, MAPK, NF-κB, and Nrf2/HO-1 pathways.

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Effects of NO-Donors on Thrombus Formation and Microcirculation in Cerebral Vessels of the Rat

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650532 ◽

1996 ◽

Vol 76 (01) ◽

pp. 111-117 ◽

Cited By ~ 10

Author(s):

Yasuto Sasaki ◽

Junji Seki ◽

John C Giddings ◽

Junichiro Yamamoto

Keyword(s):

Blood Flow ◽

Thrombus Formation ◽

Dependent Manner ◽

Red Cell ◽

Cell Velocity ◽

Red Cell Velocity ◽

The Mean ◽

Wall Shear ◽

Dose Dependent

SummarySodium nitroprusside (SNP) and 3-morpholinosydnonimine (SIN-1), are known to liberate nitric oxide (NO). In this study the effects of SNP and SIN-1 on thrombus formation in rat cerebral arterioles and venules in vivo were assessed using a helium-neon (He-Ne) laser. SNP infused at doses from 10 Μg/kg/h significantly inhibited thrombus formation in a dose dependent manner. This inhibition of thrombus formation was suppressed by methylene blue. SIN-1 at a dose of 100 Μg/kg/h also demonstrated a significant antithrombotic effect. Moreover, treatment with SNP increased vessel diameter in a dose dependent manner and enhanced the mean red cell velocity measured with a fiber-optic laser-Doppler anemometer microscope (FLDAM). Blood flow, calculated from the mean red cell velocity and vessel diameters was increased significantly during infusion. In contrast, mean wall shear rates in the arterioles and venules were not changed by SNP infusion. The results indicated that SNP and SIN-1 possessed potent antithrombotic activities, whilst SNP increased cerebral blood flow without changing wall shear rate. The findings suggest that the NO released by SNP and SIN-1 may be beneficial for the treatment and protection of cerebral infarction

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Flow-dependent regulation of endothelial Tie2 by GATA3 in vivo

Intensive Care Medicine Experimental ◽

10.1186/s40635-021-00402-x ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Temitayo O. Idowu ◽

Valerie Etzrodt ◽

Thorben Pape ◽

Joerg Heineke ◽

Klaus Stahl ◽

...

Keyword(s):

Gene Expression ◽

Regulation Of Gene Expression ◽

Experimental Models ◽

Common Denominator ◽

Dependent Manner ◽

Pulmonary Endothelium ◽

Delivery Platform ◽

Transient Overexpression ◽

Plasmid Delivery

Abstract Background Reduced endothelial Tie2 expression occurs in diverse experimental models of critical illness, and experimental Tie2 suppression is sufficient to increase spontaneous vascular permeability. Looking for a common denominator among different critical illnesses that could drive the same Tie2 suppressive (thereby leak inducing) phenotype, we identified “circulatory shock” as a shared feature and postulated a flow-dependency of Tie2 gene expression in a GATA3 dependent manner. Here, we analyzed if this mechanism of flow-regulation of gene expression exists in vivo in the absence of inflammation. Results To experimentally mimic a shock-like situation, we developed a murine model of clonidine-induced hypotension by targeting a reduced mean arterial pressure (MAP) of approximately 50% over 4 h. We found that hypotension-induced reduction of flow in the absence of confounding disease factors (i.e., inflammation, injury, among others) is sufficient to suppress GATA3 and Tie2 transcription. Conditional endothelial-specific GATA3 knockdown (B6-Gata3tm1-Jfz VE-Cadherin(PAC)-cerERT2) led to baseline Tie2 suppression inducing spontaneous vascular leak. On the contrary, the transient overexpression of GATA3 in the pulmonary endothelium (jet-PEI plasmid delivery platform) was sufficient to increase Tie2 at baseline and completely block its hypotension-induced acute drop. On the functional level, the Tie2 protection by GATA3 overexpression abrogated the development of pulmonary capillary leakage. Conclusions The data suggest that the GATA3–Tie2 signaling pathway might play a pivotal role in controlling vascular barrier function and that it is affected in diverse critical illnesses with shock as a consequence of a flow-regulated gene response. Targeting this novel mechanism might offer therapeutic opportunities to treat vascular leakage of diverse etiologies.

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Anti-tumor activity of a novel proteasome inhibitor D395 against multiple myeloma and its lower cardiotoxicity compared with carfilzomib

Cell Death and Disease ◽

10.1038/s41419-021-03701-z ◽

2021 ◽

Vol 12 (5) ◽

Author(s):

Xuxing Shen ◽

Chao Wu ◽

Meng Lei ◽

Qing Yan ◽

Haoyang Zhang ◽

...

Keyword(s):

Multiple Myeloma ◽

Proteasome Inhibitor ◽

Osteoclast Differentiation ◽

Dependent Manner ◽

Serum Enzyme ◽

Herg Channels ◽

Anti Tumor Activity ◽

Dose Dependent

AbstractCarfilzomib, a second-generation proteasome inhibitor, has significantly improved the survival rate of multiple myeloma (MM) patients, but its clinical application is still restricted by drug resistance and cardiotoxicity. Here, we identified a novel proteasome inhibitor, D395, and assessed its efficacy in treating MM as well as its cardiotoxicity at the preclinical level. The activities of purified and intracellular proteasomes were measured to determine the effect of D395 on the proteasome. CCK-8 and flow cytometry experiments were designed to evaluate the effects of D395 on cell growth and apoptosis. The effects of D395 and carfilzomib on serum enzyme activity, echocardiography features, cardiomyocyte morphology, and hERG channels were also compared. In our study, D395 was highly cytotoxic to MM cell lines and primary MM cells but not normal cells, and it was well tolerated in vivo. Similar to carfilzomib, D395 inhibited osteoclast differentiation in a dose-dependent manner. In particular, D395 exhibited lower cardiotoxicity than carfilzomib in all experiments. In conclusion, D395 is a novel irreversible proteasome inhibitor that has remarkable anti-MM activity and mild cardiotoxicity in vitro and in vivo.

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Modulatory Effects of Osthole on Lipopolysaccharides-Induced Inflammation in Caco-2 Cell Monolayer and Co-Cultures with THP-1 and THP-1-Derived Macrophages

Nutrients ◽

10.3390/nu13010123 ◽

2020 ◽

Vol 13 (1) ◽

pp. 123

Author(s):

Natalia K. Kordulewska ◽

Justyna Topa ◽

Małgorzata Tańska ◽

Anna Cieślińska ◽

Ewa Fiedorowicz ◽

...

Keyword(s):

Gene Expression ◽

Inflammatory Reaction ◽

Wide Spectrum ◽

Cell Monolayer ◽

In Vivo Studies ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Tnf Α

Lipopolysaccharydes (LPS) are responsible for the intestinal inflammatory reaction, as they may disrupt tight junctions and induce cytokines (CKs) secretion. Osthole has a wide spectrum of pharmacological effects, thus its anti-inflammatory potential in the LPS-treated Caco-2 cell line as well as in Caco-2/THP-1 and Caco-2/macrophages co-cultures was investigated. In brief, Caco-2 cells and co-cultures were incubated with LPS to induce an inflammatory reaction, after which osthole (150–450 ng/mL) was applied to reduce this effect. After 24 h, the level of secreted CKs and changes in gene expression were examined. LPS significantly increased the levels of IL-1β, -6, -8, and TNF-α, while osthole reduced this effect in a concentration-dependent manner, with the most significant decrease when a 450 ng/mL dose was applied (p < 0.0001). A similar trend was observed in changes in gene expression, with the significant osthole efficiency at a concentration of 450 ng/μL for IL1R1 and COX-2 (p < 0.01) and 300 ng/μL for NF-κB (p < 0.001). Osthole increased Caco-2 monolayer permeability, thus if it would ever be considered as a potential drug for minimizing intestinal inflammatory symptoms, its safety should be confirmed in extended in vitro and in vivo studies.

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