Abstract 114: Cytokine Response to Diet and Exercise Affects Atheromatous Matrix Metalloproteinase-2/9 Activity in Mice

2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Dong-Eog Kim
Keyword(s):  
Matrix Metalloproteinase ◽  
Visceral Fat ◽  
Near Infrared ◽  
Normal Diet ◽  
Matrix Metalloproteinase 2 ◽  
Knock Out ◽  
Diet And Exercise ◽  
Knock Out Mice ◽  
Inflammatory Milieu

Objective: To identify the principal circulating factors that modulate atheromatous matrix metalloproteinase (MMP) activity in response to diet and exercise. Methods and Results: Apolipoprotein-E knock-out mice (n=56) with preexisting plaque, fed either Western diet (WD) or normal diet (ND), underwent either 10-week treadmill exercise or not. In vivo atheromatous MMP activity was visualized using molecular imaging with an MMP-2/9 activatable near-infrared-fluorescent probe. We measured atherosclerosis-related cytokines, lipid levels, visceral fat, and correlated these outcome measures to atheromatous MMP activity. Body weight, visceral fat, and plaque size were all higher in WD-fed animals than in ND-fed animals. Exercise training did not significantly affect these parameters in either WD-fed animals or ND-fed animals. However, atheromatous MMP activity was different: ND animals with and without exercise had similar low MMP activities, WD animals without exercise had high MMP activity, and WD animals with exercise had reduced levels of MMP activity, close to the levels of ND animals. Factor analysis and path analysis showed that soluble vascular cell adhesion molecule (sVCAM)-1 was directly positively related to atheromatous MMP activity. Adiponectin was indirectly negatively related to atheromatous MMP activity by way of sVCAM-1. Resistin was indirectly positively related to atheromatous MMP activity by way of sVCAM-1. In addition, visceral fat amount was indirectly positively associated with atheromatous MMP activity, by way of adiponectin reduction and resistin elevation. Conclusion: Diet and exercise affects atheromatous MMP activity by modulating the systemic inflammatory milieu, with sVCAM-1, resistin, and adiponectin closely interacting with each other and with visceral fat.

scholarly journals Cholesterol Regulates Exosome Release in Cultured Astrocytes

2021 ◽  
Vol 12 ◽  
Author(s):  
Mohammad Abdullah ◽  
Tomohisa Nakamura ◽  
Taslima Ferdous ◽  
Yuan Gao ◽  
Yuxin Chen ◽  
...  
Keyword(s):  
High Fat Diet ◽  
Normal Diet ◽  
Cellular Cholesterol ◽  
Knock Out ◽  
Pi3k Inhibitor Ly294002 ◽  
Akt Phosphorylation ◽  
Cholesterol Levels ◽  
Cultured Astrocytes ◽  
Knock Out Mice

Exosomes are vesicles secreted by various kinds of cells, and they are rich in cholesterol, sphingomyelin (SM), phosphatidylcholine, and phosphatidylserine. Although cellular sphingolipid-mediated exosome release has been reported, the involvement of other lipid components of cell membranes in the regulation of exosome release is poorly understood. Here, we show that the level of exosome release into conditioned media is significantly reduced in cultured astrocytes prepared from apolipoprotein E (ApoE) knock-out mice when compared to those prepared from wild-type (WT) mice. The reduced level of exosome release was accompanied by elevated levels of cellular cholesterol. The addition of cholesterol to WT astrocytes significantly increased the cellular cholesterol levels and reduced exosome release. PI3K/Akt phosphorylation was enhanced in ApoE-deficient and cholesterol-treated WT astrocytes. In contrast, the depletion of cholesterol in ApoE-deficient astrocytes due to treatment with β-cyclodextrin recovered the exosome release level to a level similar to that in WT astrocytes. In addition, the reduced levels of exosome release due to the addition of cholesterol recovered to the control levels after treatment with a PI3K inhibitor (LY294002). The cholesterol-dependent regulation of exosome release was also confirmed by in vivo experiments; that is, exosome levels were significantly reduced in the CSF and blood serum of WT mice that were fed a high-fat diet and had increased cholesterol levels when compared to those in WT mice that were fed a normal diet. These results suggest that exosome release is regulated by cellular cholesterol via stimulation of the PI3K/Akt signal pathway.

scholarly journals Lack of WWC2 Protein Leads to Aberrant Angiogenesis in Postnatal Mice

2021 ◽  
Vol 22 (10) ◽  
pp. 5321
Author(s):  
Viktoria Constanze Brücher ◽  
Charlotte Egbring ◽  
Tanja Plagemann ◽  
Pavel I. Nedvetsky ◽  
Verena Höffken ◽  
...  
Keyword(s):  
Signalling Pathway ◽  
Control Group ◽  
Knock Out ◽  
Ocular Angiogenesis ◽  
Sprouting Angiogenesis ◽  
Adult Mice ◽  
Upstream Regulator ◽  
Knock Out Mice ◽  
Hippo Signalling

The WWC protein family is an upstream regulator of the Hippo signalling pathway that is involved in many cellular processes. We examined the effect of an endothelium-specific WWC1 and/or WWC2 knock-out on ocular angiogenesis. Knock-outs were induced in C57BL/6 mice at the age of one day (P1) and evaluated at P6 (postnatal mice) or induced at the age of five weeks and evaluated at three months of age (adult mice). We analysed morphology of retinal vasculature in retinal flat mounts. In addition, in vivo imaging and functional testing by electroretinography were performed in adult mice. Adult WWC1/2 double knock-out mice differed neither functionally nor morphologically from the control group. In contrast, the retinas of the postnatal WWC knock-out mice showed a hyperproliferative phenotype with significantly enlarged areas of sprouting angiogenesis and a higher number of tip cells. The branching and end points in the peripheral plexus were significantly increased compared to the control group. The deletion of the WWC2 gene was decisive for these effects; while knocking out WWC1 showed no significant differences. The results hint strongly that WWC2 is an essential regulator of ocular angiogenesis in mice. As an activator of the Hippo signalling pathway, it prevents excessive proliferation during physiological angiogenesis. In adult animals, WWC proteins do not seem to be important for the maintenance of the mature vascular plexus.

FcγRIII (CD16)-Deficient Mice Show IgG Isotype-Dependent Protection to Experimental Autoimmune Hemolytic Anemia

Blood ◽  
1998 ◽  
Vol 92 (11) ◽  
pp. 3997-4002 ◽  
Author(s):  
Dirk Meyer ◽  
Carsten Schiller ◽  
Jürgen Westermann ◽  
Shozo Izui ◽  
Wouter L. W. Hazenbos ◽  
...  
Keyword(s):  
Hemolytic Anemia ◽  
Autoimmune Hemolytic Anemia ◽  
Knock Out ◽  
Effector Cells ◽  
Igg Isotypes ◽  
Knock Out Mice ◽  
Deficient Mice ◽  
Experimental Autoimmune

Abstract In autoimmune hemolytic anemia (AIHA), there is accumulating evidence for an involvement of FcγR expressed by phagocytic effector cells, but demonstration of a causal relationship between individual FcγRs and IgG isotypes for disease development is lacking. Although the relevance of IgG isotypes to human AIHA is limited, we could show a clear IgG isotype dependency in murine AIHA using pathogenic IgG1 (105-2H) and IgG2a (34-3C) autoreactive anti–red blood cell antibodies in mice defective for FcγRIII, and comparing the clinical outcome to those in wild-type mice. FcγRIII-deficient mice were completely resistent to the pathogenic effects of 105-2H monoclonal antibody, as shown by a lack of IgG1-mediated erythrophagocytosis in vitro and in vivo. In addition, the IgG2a response by 34-3C induced a less severe but persistent AIHA in FcγRIII knock-out mice, as documented by a decrease in hematocrit. Blocking studies indicated that the residual anemic phenotype induced by 34-3C in the absence of FcγRIII reflects an activation of FcγRI that is normally coexpressed with FcγRIII on macrophages. Together these results show that the pathogenesis of AIHA through IgG1-dependent erythrophagocytosis is exclusively mediated by FcγRIII and further suggest that FcγRI, in addition to FcγRIII, contributes to this autoimmune disease when other IgG isotypes such as IgG2a are involved.

scholarly journals Pannexin-1 Deficient Mice Have an Increased Susceptibility for Atrial Fibrillation and Show a QT-Prolongation Phenotype

2016 ◽  
Vol 38 (2) ◽  
pp. 487-501 ◽  
Author(s):  
Stella Petric ◽  
Sofia Klein ◽  
Lisa Dannenberg ◽  
Tillman Lahres ◽  
Lukas Clasen ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Cardiac Electrophysiology ◽  
Electrophysiological Study ◽  
Atp Release ◽  
Release Channel ◽  
Knock Out ◽  
Pannexin 1 ◽  
Significant Prolongation ◽  
Knock Out Mice

Background/Aims: Pannexin-1 (Panx1) is an ATP release channel that is ubiquitously expressed and coupled to several ligand-gated receptors. In isolated cardiac myocytes, Panx1 forms large conductance channels that can be activated by Ca2+ release from the sarcoplasmic reticulum. Here we characterized the electrophysiological function of these channels in the heart in vivo, taking recourse to mice with Panx1 ablation. Methods: Cardiac phenotyping of Panx1 knock-out mice (Panx1-/-) was performed by employing a molecular, cellular and functional approach, including echocardiography, surface and telemetric ECG recordings with QT analysis, physical stress testing and quantification of heart rate variability. In addition, an in vivo electrophysiological study entailed programmed electrical stimulation using an intracardiac octapolar catheter. Results: Panx1 deficiency results in a higher incidence of AV-block, delayed ventricular depolarisation, significant prolongation of QT- and rate corrected QT-interval and a higher incidence of atrial fibrillation after intraatrial burst stimulation. Conclusion: Panx1 seems to play an important role in murine cardiac electrophysiology and warrants further consideration in the context of hereditary forms of atrial fibrillation.

scholarly journals Lidocaine Alleviates Sepsis-Induced Acute Lung Injury in Mice by Suppressing Tissue Factor and Matrix Metalloproteinase-2/9

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Binbin Zheng ◽  
Hongbo Yang ◽  
Jianan Zhang ◽  
Xueli Wang ◽  
Hao Sun ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Matrix Metalloproteinase ◽  
Gelatin Zymography ◽  
Neutrophil Infiltration ◽  
Negative Regulator ◽  
Matrix Metalloproteinase 2 ◽  
Cytokine Signaling

Acute lung injury (ALI) is one of the fatal symptoms of sepsis. However, there were no effective clinical treatments. TF accumulation-induced fibrin deposit formations and coagulation abnormalities in pulmonary vessels contribute to the lethality of ALI. Suppressor of cytokine signaling 3 (SOCS3) acts as an endogenous negative regulator of the TLR4/TF pathway. We hypothesized that inducing SOCS3 expression using lidocaine to suppress the TLR4/TF pathway may alleviate ALI. Hematoxylin and eosin (H&E), B-mode ultrasound, and flow cytometry were used to measure the pathological damage of mice. Gelatin zymography was used to measure matrix metalloproteinase-2/9 (MMP-2/9) activities. Western blot was used to assay the expression of protein levels. Here, we show that lidocaine could increase the survival rate of ALI mice and ameliorate the lung injury of ALI mice including reducing the edema, neutrophil infiltration, and pulmonary thrombosis formation and increasing blood flow velocity. Moreover, in vitro and in vivo, lidocaine could increase the expression of p-AMPK and SOCS3 and subsequently decrease the expression of p-ASK1, p-p38, TF, and the activity of MMP-2/9. Taken together, our study demonstrated that lidocaine could inhibit the TLR4/ASK1/TF pathway to alleviate ALI via activating AMPK-SOCS3 axis.

scholarly journals Long Noncoding RNA TUG1/miR-29c Axis Affects Cell Proliferation, Invasion, and Migration in Human Pancreatic Cancer

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Yebin Lu ◽  
Ling Tang ◽  
Zhipeng Zhang ◽  
Shengyu Li ◽  
Shuai Liang ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Cell Proliferation ◽  
Matrix Metalloproteinase ◽  
Human Pancreatic Cancer ◽  
Matrix Metalloproteinase 2 ◽  
Integrin Subunit ◽  
Normal Tissues

Given the low resection rate and chemoresistance of patients with pancreatic cancer (PC), their survival rates are typically poor. Long noncoding RNAs (lncRNAs) have recently been shown to play an important role in tumourigenesis and human cancer progression, including in PC. In this study, we aimed to investigate the role of taurine-upregulated gene 1 (TUG1) in PC. A quantitative polymerase chain reaction was used to analyse TUG1 expression in PC tissues and peritumoural normal tissues. TUG1 was overexpressed in PC tissues compared with that in peritumoural normal tissues, and the high expression of TUG1 was associated with the poor prognosis of patients with PC. Furthermore, TUG1 knockdown significantly inhibited the proliferation and invasion of PC cells both in vitro and in vivo, while overexpression TUG1 promoted tumour cell proliferation, migration, and invasion. TUG1 directly targeted miR-29c, a tumour suppressor in several cancers. TUG1 knockdown significantly increased the expression of miR-29c and subsequently induced the downregulation of integrin subunit beta 1 (ITGB1), matrix metalloproteinase-2 (MMP2), and matrix metalloproteinase-9 (MMP9). The downregulation of miR-29c abolished the TUG1 knockdown-mediated inhibition of tumour growth in vitro and in vivo, whereas the upregulation of miR-29c enhanced the effects of TUG1 knockdown on PC cells. In conclusion, we demonstrate for the first time the oncogenic role of TUG1 in PC. The downregulation of TUG1 significantly inhibited the growth and migratory ability of PC cells in vitro and in vivo by targeting miR-29c. Our study provides a novel potential diagnostic biomarker and therapeutic target for PC.

Mucin O-glycosylating enzyme GALNT2 facilitates the malignant character of glioma by activating the EGFR/PI3K/Akt/mTOR axis

2019 ◽  
Vol 133 (10) ◽  
pp. 1167-1184 ◽  
Author(s):  
Zhongzheng Sun ◽  
Hao Xue ◽  
Yan Wei ◽  
Chaochao Wang ◽  
Rui Yu ◽  
...  
Keyword(s):  
Matrix Metalloproteinase ◽  
Glioma Cell ◽  
Proportional Hazards Model ◽  
Cox Proportional Hazards ◽  
Cox Proportional Hazards Model ◽  
The Cancer Genome Atlas ◽  
Matrix Metalloproteinase 2 ◽  
Migration And Invasion ◽  
Expression Levels

AbstractN-Acetylgalactosaminyltransferase 2 (GALNT2), the enzyme that regulates the initial step of mucin O-glycosylation, has been reported to play a role in influencing the malignancy of various cancers. However, the mechanism through which it influences gliomas is still unknown. In the current study, the Cox proportional hazards model was used to select genes. Data obtained from The Cancer Genome Atlas (TCGA) database and immunohistochemistry (IHC) of clinical specimens showed that increased GALNT2 expression levels were associated with an unfavorable prognosis and a higher tumor grade in human gliomas. Then, GALNT2 knockdown and overexpression were performed in glioma cell lines and verified by quantitative real-time PCR (qRT-PCR) and Western blotting. Functional assays demonstrated that GALNT2 was closely related to glioma cell proliferation, cycle transition, migration and invasion. Western blot analysis and lectin pull-down assays indicated that GALNT2 knockdown decreased the level of phosphorylated epidermal growth factor receptor (EGFR) and the expression of the Tn antigen on EGFR and affected the expression levels of p21, cyclin-dependent kinase 4 (CDK4), cyclinD1, matrix metalloproteinase 2 (MMP2) and matrix metalloproteinase 9 (MMP9) through the EGFR/PI3K/Akt/mTOR pathway. GALNT2 overexpression had the opposite effects. In vivo, the growth of orthotopic glioma xenografts in nude mice was distinctly inhibited by the expression of GALNT2 shRNA, and the tumors with GALNT2 shRNA exhibited less aggressiveness and reduced expression of Ki67 and MMP2. Overall, GALNT2 facilitates the malignant characteristics of glioma by influencing the O-glycosylation and phosphorylation of EGFR and the subsequent downstream PI3K/Akt/mTOR axis. Therefore, GALNT2 may serve as a novel biomarker and a potential target for future therapy of glioma.

Sign in / Sign up

Export Citation Format

Share Document