Differential requirement for A2a and A3 adenosine receptors for the protective effect of inosine in vivo

AbstractInosine is an endogenous nucleoside with immunosuppressive properties that is known to inhibit the accumulation of proinflammatory cytokines and protect mice from endotoxin-induced inflammation and lung tissue damage. There are no known receptors specific for inosine, but A3 adenosine receptors (A3Rs) have been shown to bind inosine, resulting in mast cell degranulation and increased vascular permeability. The present study specifically addresses the requirement for A2aR and/or A3R for the protective effect of inosine in 2 experimental in vivo models of inflammatory disease. The data show that A3R is essential for protection against ConA-induced fulminant hepatitis since only A3R-expressing mice were protected by inosine whereas wild-type and A2aR-deficient mice exhibited severe liver damage even after administration of inosine. In addition, we show in a model of LPS-induced endotoxemia that inosine protected both A2aR-/- and A3R-/- mice from inflammation, but not A2aA3R double-null mice, indicating that in this model both A2aR and A3R were used by inosine. Thus, we demonstrate that A2a and A3 adenosine receptors are differentially utilized by inosine for the down-regulation of tissue damage under different inflammatory conditions in vivo. (Blood. 2003;102:4472-4478)

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Glucose Transporter 8 (GLUT8) Regulates Enterocyte Fructose Transport and Global Mammalian Fructose Utilization

Endocrinology ◽

10.1210/en.2012-1541 ◽

2012 ◽

Vol 153 (9) ◽

pp. 4181-4191 ◽

Cited By ~ 42

Author(s):

Brian J. DeBosch ◽

Maggie Chi ◽

Kelle H. Moley

Keyword(s):

Glucose Transporter ◽

Serum Insulin ◽

Density Lipoprotein ◽

Wild Type ◽

In Vivo Models ◽

The Metabolic Syndrome ◽

High Fructose

Enterocyte fructose absorption is a tightly regulated process that precedes the deleterious effects of excess dietary fructose in mammals. Glucose transporter (GLUT)8 is a glucose/fructose transporter previously shown to be expressed in murine intestine. The in vivo function of GLUT8, however, remains unclear. Here, we demonstrate enhanced fructose-induced fructose transport in both in vitro and in vivo models of enterocyte GLUT8 deficiency. Fructose exposure stimulated [14C]-fructose uptake and decreased GLUT8 protein abundance in Caco2 colonocytes, whereas direct short hairpin RNA-mediated GLUT8 knockdown also stimulated fructose uptake. To assess GLUT8 function in vivo, we generated GLUT8-deficient (GLUT8KO) mice. GLUT8KO mice exhibited significantly greater jejunal fructose uptake at baseline and after high-fructose diet (HFrD) feeding vs. wild-type mice. Strikingly, long-term HFrD feeding in GLUT8KO mice exacerbated fructose-induced increases in blood pressure, serum insulin, low-density lipoprotein and total cholesterol vs. wild-type controls. Enhanced fructose uptake paralleled with increased abundance of the fructose and glucose transporter, GLUT12, in HFrD-fed GLUT8KO mouse enterocytes and in Caco2 cultures exposed to high-fructose medium. We conclude that GLUT8 regulates enterocyte fructose transport by regulating GLUT12, and that disrupted GLUT8 function has deleterious long-term metabolic sequelae. GLUT8 may thus represent a modifiable target in the prevention and treatment of malnutrition or the metabolic syndrome.

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Systems Modeling of the Role of Interleukin-21 in the Maintenance of Effector CD4+ T Cell Responses during Chronic Helicobacter pylori Infection

mBio ◽

10.1128/mbio.01243-14 ◽

2014 ◽

Vol 5 (4) ◽

Cited By ~ 36

Author(s):

Adria Carbo ◽

Danyvid Olivares-Villagómez ◽

Raquel Hontecillas ◽

Josep Bassaganya-Riera ◽

Rupesh Chaturvedi ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

T Cell ◽

Wild Type ◽

Content Type ◽

Interleukin 21 ◽

H Pylori ◽

Deficient Mice

ABSTRACTThe development of gastritis duringHelicobacter pyloriinfection is dependent on an activated adaptive immune response orchestrated by T helper (Th) cells. However, the relative contributions of the Th1 and Th17 subsets to gastritis and control of infection are still under investigation. To investigate the role of interleukin-21 (IL-21) in the gastric mucosa duringH. pyloriinfection, we combined mathematical modeling of CD4+T cell differentiation within vivomechanistic studies. We infected IL-21-deficient and wild-type mice withH. pyloristrain SS1 and assessed colonization, gastric inflammation, cellular infiltration, and cytokine profiles. ChronicallyH. pylori-infected IL-21-deficient mice had higherH. pyloricolonization, significantly less gastritis, and reduced expression of proinflammatory cytokines and chemokines compared to these parameters in infected wild-type littermates. Thesein vivodata were used to calibrate anH. pyloriinfection-dependent, CD4+T cell-specific computational model, which then described the mechanism by which IL-21 activates the production of interferon gamma (IFN-γ) and IL-17 during chronicH. pyloriinfection. The model predicted activated expression of T-bet and RORγt and the phosphorylation of STAT3 and STAT1 and suggested a potential role of IL-21 in the modulation of IL-10. Driven by our modeling-derived predictions, we found reduced levels of CD4+splenocyte-specifictbx21androrcexpression, reduced phosphorylation of STAT1 and STAT3, and an increase in CD4+T cell-specific IL-10 expression inH. pylori-infected IL-21-deficient mice. Our results indicate that IL-21 regulates Th1 and Th17 effector responses during chronicH. pyloriinfection in a STAT1- and STAT3-dependent manner, therefore playing a major role controllingH. pyloriinfection and gastritis.IMPORTANCEHelicobacter pyloriis the dominant member of the gastric microbiota in more than 50% of the world’s population.H. pyloricolonization has been implicated in gastritis and gastric cancer, as infection withH. pyloriis the single most common risk factor for gastric cancer. Current data suggest that, in addition to bacterial virulence factors, the magnitude and types of immune responses influence the outcome of colonization and chronic infection. This study uses a combined computational and experimental approach to investigate how IL-21, a proinflammatory T cell-derived cytokine, maintains the chronic proinflammatory T cell immune response driving chronic gastritis duringH. pyloriinfection. This research will also provide insight into a myriad of other infectious and immune disorders in which IL-21 is increasingly recognized to play a central role. The use of IL-21-related therapies may provide treatment options for individuals chronically colonized withH. pylorias an alternative to aggressive antibiotics.

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Urokinase-dependent plasminogen activation is required for efficient skeletal muscle regeneration in vivo

Blood ◽

10.1182/blood.v97.6.1703 ◽

2001 ◽

Vol 97 (6) ◽

pp. 1703-1711 ◽

Cited By ~ 82

Author(s):

Frederic Lluı́s ◽

Josep Roma ◽

Mònica Suelves ◽

Maribel Parra ◽

Gloria Aniorte ◽

...

Keyword(s):

Skeletal Muscle ◽

Plasminogen Activator ◽

Muscle Regeneration ◽

Plasminogen Activators ◽

Skeletal Muscle Regeneration ◽

Plasminogen Activation ◽

Wild Type ◽

Type Plasminogen Activator ◽

Deficient Mice

Plasminogen activators urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA) are extracellular proteases involved in various tissue remodeling processes. A requirement for uPA activity in skeletal myogenesis was recently demonstrated in vitro. The role of plasminogen activators in skeletal muscle regeneration in vivo in wild-type, uPA-deficient, and tPA-deficient mice is investigated here. Wild-type and tPA−/− mice completely repaired experimentally damaged skeletal muscle. In contrast, uPA−/− mice had a severe regeneration defect, with decreased recruitment of blood-derived monocytes to the site of injury and with persistent myotube degeneration. In addition, uPA-deficient mice accumulated fibrin in the degenerating muscle fibers; however, the defibrinogenation of uPA-deficient mice resulted in a correction of the muscle regeneration defect. A similar severe regeneration deficit with persistent fibrin deposition was also reproducible in plasminogen-deficient mice after injury, suggesting that fibrinolysis by uPA-mediated plasminogen activation plays a fundamental role in skeletal muscle regeneration. In conclusion, the uPA-plasmin system is identified as a critical component of the mammalian skeletal muscle regeneration process, possibly because it prevents intramuscular fibrin accumulation and contributes to the adequate inflammatory response after injury. These studies demonstrate the requirement of an extracellular proteolytic cascade during muscle regeneration in vivo.

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Pengaruh Pemberian Taurin terhadap Gambaran Histopatologi Paru Mencit (Mus musculus) yang Diinduksi Karsinogen Benzo(α)Piren secara In Vivo

Jurnal Natur Indonesia ◽

10.31258/jnat.17.1.22-32 ◽

2017 ◽

Vol 17 (1) ◽

pp. 22

Author(s):

Arini Pradita Roselyn ◽

Endang Linirin Widiastuti ◽

G. Nugroho Susanto ◽

Sutyarso '

Keyword(s):

Lung Tissue ◽

Mus Musculus ◽

Tissue Damage ◽

Corn Oil ◽

Group Vi ◽

Normal Tissues ◽

Randomized Design ◽

Group I ◽

Lung Tissue Damage

Lung cancer is a disease that causes high mortality. Drugs used to prevent and cure cancer mostly causes intoxicity to the normal tissues due to its less effectiveness. Therefore, it is necessary to find out any agent or substance which works much more effective and safe for cancer treatment. The aim of the study was to elucidate the role of taurine on the lung tissue of mice (Mus musculus) induced by carcinogenic benzo(α)pyrene. The experiment was conducted in a completely randomized design with 5 replications. Six treatment groups were perfomed. Group I was given 0.2 mL of corn oil and given aquadest until the end of the study period, group II was induced by benzo(α)pyrene without administration of taurine, group III before induced with benzo(α)pyrene, was given taurine dosage 7.8 mg/BW/day for two weeks, group IV after induced benzo(α)pyrene, was given taurine with dosage 3.9 mg/BW/day, group V after induced benzo(α)pyrene, was given taurine with dosage7. 8 mg/BW/day, group VI after induced with benzo(α)pyrene, was given taurine with dosage 15.6 mg/BW/day. The results of the Kruskal-Wallis analysis and one way ANOVA with LSD (p>0,05) showed that taurine reduced lung tissue damage 72.73% due to the administration of benzo(α)pyrene of 0.3 mg/BW/day. In addition, the effective dose of taurine reduce lung tissue damage was 15.6 mg/BW/day.

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An in vivo inflammatory loop potentiates KRAS blockade

10.1101/629139 ◽

2019 ◽

Cited By ~ 1

Author(s):

Kristina A.M. Arendt ◽

Giannoula Ntaliarda ◽

Vasileios Armenis ◽

Danai Kati ◽

Christin Henning ◽

...

Keyword(s):

Interleukin 1Β ◽

Wild Type ◽

Poor Survival ◽

Murine Bone Marrow ◽

Chemokine Ligand ◽

Isoprenylcysteine Carboxylmethyltransferase ◽

Chemokine Ligand 2 ◽

Deficient Mice

ABSTRACTKRAS inhibitors perform inferior to other targeted drugs. To investigate a possible reason for this, we treated cancer cells with KRAS inhibitors deltarasin (targeting phosphodiesterase-δ), cysmethynil (targeting isoprenylcysteine carboxylmethyltransferase), and AA12 (targeting KRASG12C), and silenced/overexpressed mutant KRAS using custom vectors. We show that KRAS-mutant tumor cells exclusively respond to KRAS blockade in vivo, because the oncogene co-opts host myeloid cells via a C-C-motif chemokine ligand 2/interleukin-1β signaling loop for sustained tumorigenicity. Indeed, KRAS-mutant tumors did not respond to deltarasin in Ccr2 and Il1b gene-deficient mice, but were deltarasin-sensitive in wild-type and Ccr2-deficient mice adoptively transplanted with wild-type murine bone marrow. A KRAS-dependent pro-inflammatory transcriptome was prominent in human cancers with high KRAS mutation prevalence and predicted poor survival. Hence the findings support that in vitro systems are suboptimal for anti-KRAS drug screens, and suggest that interleukin-1β blockade might be specific for KRAS-mutant cancers.

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Endothelial E- and P-selectin expression in iNOS- deficient mice exposed to polymicrobial sepsis

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.2001.280.2.g291 ◽

2001 ◽

Vol 280 (2) ◽

pp. G291-G297 ◽

Cited By ~ 20

Author(s):

Cameron W. Lush ◽

Gediminas Cepinskas ◽

William J. Sibbald ◽

Peter R. Kvietys

Keyword(s):

Leukocyte Adhesion ◽

Cecal Ligation ◽

Leukocyte Rolling ◽

Wild Type ◽

Endothelial Adhesion Molecule ◽

Acute Peritonitis ◽

Leukocyte Accumulation ◽

Deficient Mice

In vitro, nitric oxide (NO) decreases leukocyte adhesion to endothelium by attenuating endothelial adhesion molecule expression. In vivo, lipopolysaccharide-induced leukocyte rolling and adhesion was greater in inducible NO synthase (iNOS)−/− mice than in wild-type mice. The objective of this study was to assess E- and P-selectin expression in the microvasculature of iNOS−/− and wild-type mice subjected to acute peritonitis by cecal ligation and perforation (CLP). E- and P-selectin expression were increased in various organs within the peritoneum of wild-type animals after CLP. This CLP-induced upregulation of E- and P-selectin was substantially reduced in iNOS−/− mice. Tissue myeloperoxidase (MPO) activity was increased to a greater extent in the gut of wild-type than in iNOS−/− mice subjected to CLP. In the lung, the reduced expression of E-selectin in iNOS−/− mice was not associated with a decrease in MPO. Our findings indicate that NO derived from iNOS plays an important role in sepsis-induced increase in selectin expression in the systemic and pulmonary circulation. However, in iNOS−/− mice, sepsis-induced leukocyte accumulation is affected in the gut but not in the lungs.

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In Vitro and In Vivo Inhibitory Effect of Citrus Junos Tanaka Peel Extract against Oxidative Stress-Induced Apoptotic Death of Lung Cells

Antioxidants ◽

10.3390/antiox9121231 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1231

Author(s):

Jin Woo Kim ◽

Eun Hee Jo ◽

Ji Eun Moon ◽

Hanvit Cha ◽

Moon Han Chang ◽

...

Keyword(s):

Oxidative Stress ◽

Protective Effect ◽

Inhibitory Effect ◽

Lung Cells ◽

In Vivo Models ◽

Citrus Junos ◽

Induced Apoptosis ◽

Peel Extract

Various stresses derived from both internal and external oxidative environments lead to the excessive production of reactive oxygen species (ROS) causing progressive intracellular oxidative damage and ultimately cell death. The objective of this study was to evaluate the protective effects of Citrus junos Tanaka peel extract (CE) against oxidative-stress induced the apoptosis of lung cells and the associated mechanisms of action using in vitro and in vivo models. The protective effect of CE was evaluated in vitro in NCI-H460 human lung cells exposed to pro-oxidant H2O2. The preventive effect of CE (200 mg/kg/day, 10 days) against pulmonary injuries following acrolein inhalation (10 ppm for 12 h) was investigated using an in vivo mouse model. Herein, we demonstrated the inhibitory effect of CE against the oxidative stress-induced apoptosis of lung cells under a highly oxidative environment. The function of CE is linked with its ability to suppress ROS-dependent, p53-mediated apoptotic signaling. Furthermore, we evaluated the protective role of CE against apoptotic pulmonary injuries associated with the inhalation of acrolein, a ubiquitous and highly oxidizing environmental respiratory pollutant, through the attenuation of oxidative stress. The results indicated that CE exhibits a protective effect against the oxidative stress-induced apoptosis of lung cells in both in vitro and in vivo models.

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A Role for Mac-1 (CDIIb/CD18) in Immune Complex–stimulated Neutrophil Function In Vivo: Mac-1 Deficiency Abrogates Sustained Fcγ Receptor–dependent Neutrophil Adhesion and Complement-dependent Proteinuria in Acute Glomerulonephritis

Journal of Experimental Medicine ◽

10.1084/jem.186.11.1853 ◽

1997 ◽

Vol 186 (11) ◽

pp. 1853-1863 ◽

Cited By ~ 149

Author(s):

Tao Tang ◽

Alexander Rosenkranz ◽

Karel J.M. Assmann ◽

Michael J. Goodman ◽

Jose-Carlos Gutierrez-Ramos ◽

...

Keyword(s):

Immune Complex ◽

Mutant Mice ◽

Polymorphonuclear Neutrophil ◽

Complement C3 ◽

Acute Glomerulonephritis ◽

Wild Type ◽

Filamentous Actin ◽

Deficient Mice

Mac-1 (αmβ2), a leukocyte adhesion receptor, has been shown in vitro to functionally interact with Fcγ receptors to facilitate immune complex (IC)–stimulated polymorphonuclear neutrophil (PMN) functions. To investigate the relevance of Mac-1–FcγR interactions in IC-mediated injury in vivo, we induced a model of Fc-dependent anti–glomerular basement membrane (GBM) nephritis in wild-type and Mac-1–deficient mice by the intravenous injection of anti-GBM antibody. The initial glomerular PMN accumulation was equivalent in Mac-1 null and wild-type mice, but thereafter increased in wild-type and decreased in mutant mice. The absence of Mac-1 interactions with obvious ligands, intercellular adhesion molecule 1 (ICAM-1), and C3 complement, is not responsible for the decrease in neutrophil accumulation in Mac-1– deficient mice since glomerular PMN accumulation in mice deficient in these ligands was comparable to those in wild-type mice. In vitro studies showed that spreading of Mac-1–null PMNs to IC-coated dishes was equivalent to that of wild-type PMNs at 5–12 min but was markedly reduced thereafter, and was associated with an inability of mutant neutrophils to redistribute filamentous actin. This suggests that in vivo, Mac-1 is not required for the initiation of Fc-mediated PMN recruitment but that Mac-1–FcγR interactions are required for filamentous actin reorganization leading to sustained PMN adhesion, and this represents the first demonstration of the relevance of Mac-1–FcγR interactions in vivo. PMN-dependent proteinuria, maximal in wild-type mice at 8 h, was absent in Mac-1 mutant mice at all time points. Complement C3–deficient mice also had significantly decreased proteinuria compared to wild-type mice. Since Mac-1 on PMNs is the principal ligand for ic3b, an absence of Mac-1 interaction with C3 probably contributed to the abrogation of proteinuria in Mac-1–null mice.

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Differential response to myocardial reperfusion injury in eNOS-deficient mice

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00855.2001 ◽

2002 ◽

Vol 282 (6) ◽

pp. H2422-H2426 ◽

Cited By ~ 55

Author(s):

Brent R. Sharp ◽

Steven P. Jones ◽

David M. Rimmer ◽

David J. Lefer

Keyword(s):

Ischemia Reperfusion ◽

Myocardial Necrosis ◽

In Vivo Model ◽

Pcr Analysis ◽

Inos Mrna ◽

Mrna Levels ◽

Wild Type ◽

Significant Difference ◽

Deficient Mice

Two strains of endothelial nitric oxide synthase (eNOS)-deficient (−/−) mice have been developed that respond differently to myocardial ischemia-reperfusion (MI/R). We evaluated both strains of eNOS−/− mice in an in vivo model of MI/R. Harvard (Har) eNOS−/− mice ( n = 12) experienced an 84% increase in myocardial necrosis compared with wild-type controls ( P < 0.05). University of North Carolina (UNC) eNOS−/−( n = 10) exhibited a 52% reduction in myocardial injury versus wild-type controls ( P < 0.05). PCR analysis of myocardial inducible NO synthase (iNOS) mRNA levels revealed a significant ( P < 0.05) increase in the UNC eNOS−/− mice compared with wild-type mice, and there was no significant difference between the Har eNOS−/− and wild-type mice. UNC eNOS−/− mice treated with an iNOS inhibitor (1400W) exacerbated the extent of myocardial necrosis. When treated with 1400W, Har eNOS−/− did not exhibit a significant increase in myocardial necrosis. These data demonstrate that two distinct strains of eNOS−/− mice display opposite responses to MI/R. Although the protection seen in the UNC eNOS−/− mouse may result from compensatory increases in iNOS, other genes may be involved.

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Dephosphorylation of protamine 2 at serine 56 is crucial for murine sperm maturation in vivo

Science Signaling ◽

10.1126/scisignal.aao7232 ◽

2019 ◽

Vol 12 (574) ◽

pp. eaao7232 ◽

Cited By ~ 3

Author(s):

Katsuhiko Itoh ◽

Gen Kondoh ◽

Hitoshi Miyachi ◽

Manabu Sugai ◽

Yoshiyuki Kaneko ◽

...

Keyword(s):

Posttranslational Modification ◽

Sperm Maturation ◽

Sperm Cells ◽

Chromatin Binding ◽

Wild Type ◽

Underlying Mechanisms ◽

Deficient Mice ◽

Protamine 2

The posttranslational modification of histones is crucial in spermatogenesis, as in other tissues; however, during spermiogenesis, histones are replaced with protamines, which are critical for the tight packaging of the DNA in sperm cells. Protamines are also posttranslationally modified by phosphorylation and dephosphorylation, which prompted our investigation of the underlying mechanisms and biological consequences of their regulation. On the basis of a screen that implicated the heat shock protein Hspa4l in spermatogenesis, we generated mice deficient in Hspa4l (Hspa4l-null mice), which showed male infertility and the malformation of sperm heads. These phenotypes are similar to those of Ppp1cc-deficient mice, and we found that the amount of a testis- and sperm-specific isoform of the Ppp1cc phosphatase (Ppp1cc2) in the chromatin-binding fraction was substantially less in Hspa4l-null spermatozoa than that in those of wild-type mice. We further showed that Ppp1cc2 was a substrate of the chaperones Hsc70 and Hsp70 and that Hspa4l enhanced the release of Ppp1cc2 from these complexes, enabling the freed Ppp1cc2 to localize to chromatin. Pull-down and in vitro phosphatase assays suggested the dephosphorylation of protamine 2 at serine 56 (Prm2 Ser56) by Ppp1cc2. To confirm the biological importance of Prm2 Ser56 dephosphorylation, we mutated Ser56 to alanine in Prm2 (Prm2 S56A). Introduction of this mutation to Hspa4l-null mice (Hspa4l−/−; Prm2S56A/S56A) restored the malformation of sperm heads and the infertility of Hspa4l−/− mice. The dephosphorylation signal to eliminate phosphate was crucial, and these results unveiled the mechanism and biological relevance of the dephosphorylation of Prm2 for sperm maturation in vivo.

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