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Sample records for a2 receptor-deficient mice

  1. EphA2-receptor deficiency exacerbates myocardial infarction and reduces survival in hyperglycemic mice.

    PubMed

    DuSablon, Augustin; Kent, Susan; Coburn, Anita; Virag, Jitka

    2014-08-13

    We have previously shown that EphrinA1/EphA expression profile changes in response to myocardial infarction (MI), exogenous EphrinA1-Fc administration following MI positively influences wound healing, and that deletion of the EphA2 Receptor (EphA2-R) exacerbates injury and remodeling. To determine whether or not ephrinA1-Fc would be of therapeutic value in the hyperglycemic infarcted heart, it is critical to evaluate how ephrinA1/EphA signaling changes in the hyperglycemic myocardium in response to MI. Streptozotocin (STZ)-induced hyperglycemia in wild type (WT) and EphA2-receptor mutant (EphA2-R-M) mice was initiated by an intraperitoneal injection of STZ (150 mg/kg) 10 days before surgery. MI was induced by permanent ligation of the left anterior descending coronary artery and analyses were performed at 4 days post-MI. ANOVAs with Student-Newman Keuls multiple comparison post-hoc analysis illustrated which groups were significantly different, with significance of at least p < 0.05. Both WT and EphA2-R-M mice responded adversely to STZ, but only hyperglycemic EphA2-R-M mice had lower ejection fraction (EF) and fractional shortening (FS). At 4 days post-MI, we observed greater post-MI mortality in EphA2-R-M mice compared with WT and this was greater still in the EphA2-R-M hyperglycemic mice. Although infarct size was greater in hyperglycemic WT mice vs normoglycemic mice, there was no difference between hyperglycemic EphA2-R-M mice and normoglycemic EphA2-R-M mice. The hypertrophic response that normally occurs in viable myocardium remote to the infarct was noticeably absent in epicardial cardiomyocytes and cardiac dysfunction worsened in hyperglycemic EphA2-R-M hearts post-MI. The characteristic interstitial fibrotic response in the compensating myocardium remote to the infarct also did not occur in hyperglycemic EphA2-R-M mouse hearts to the same extent as that observed in the hyperglycemic WT mouse hearts. Differences in neutrophil and pan

  2. Dihydromyricetin ameliorates atherosclerosis in LDL receptor deficient mice.

    PubMed

    Liu, Ting Ting; Zeng, Yi; Tang, Kun; Chen, XueMeng; Zhang, Wei; Xu, Xiao Le

    2017-07-01

    Dihydromyricetin, the most abundant flavonoid in Ampelopsis grossedentata, exerts numerous pharmacological activities, including anti-inflammatory, antioxidant, hepatoprotective, and lipid regulatory activities; however, its protective effect against atherosclerosis remains poorly understood. The aim of the present study was to evaluate the effects of dihydromyricetin on high fat diet (HFD)-induced atherosclerosis using LDL receptor deficient (LDLr -/- ) mice. Blood samples were collected for determination of serum lipid profiles, oxidized LDL (ox-LDL) and pro-inflammatory cytokines. Histology, hepatic lipid content, quantification of atherosclerosis, assessment of oxidative stress and inflammation were performed on liver and aorta samples by molecular biology methods. The effects of dihydromyricetin on ox-LDL-induced human umbilical vein endothelial cells (HUVECs) dysfunction and foam cell formation were further studied. (1) Dihydromyricetin ameliorated hyperlipidemia, reduced serum ox-LDL, IL-6 and TNF-α levels in HFD-fed LDLr -/- mice. Moreover, (2) dihydromyricetin suppressed hepatic lipid accumulation and increased protein expressions of PPARα, LXRα and ABCA1. (3) It inhibited atherosclerotic lesion formation and favoured features of plaque stability. (4) Dihydromyricetin prevented hepatic and aortic inflammation as evidenced by the reduced IL-6 and TNF-α mRNA expression; (5) it prevented hepatic and aortic oxidative stress by normalizing activities of antioxidant enzymes in the liver and suppressing reactive oxygen species generation and NOX2 protein expression in both liver and aorta; (6) it inhibited oxLDL-induced injury, monocytes adhesion and oxidative stress in HUVECs and (7) inhibited macrophage foam cell formation and enhanced cholesterol efflux. These findings suggest that dihydromyricetin could reduce atherosclerosis via its pleiotropic effects, including improvement of endothelial dysfunction, inhibition of macrophage foam cell formation

  3. Resistance of Fc receptor- deficient mice to fatal glomerulonephritis.

    PubMed Central

    Park, S Y; Ueda, S; Ohno, H; Hamano, Y; Tanaka, M; Shiratori, T; Yamazaki, T; Arase, H; Arase, N; Karasawa, A; Sato, S; Ledermann, B; Kondo, Y; Okumura, K; Ra, C; Saito, T

    1998-01-01

    Immune complex-mediated inflammation is a common mechanism of various autoimmune diseases. Glomerulonephritis (GN) is one of these diseases, and the main mechanism of the induction of GN has been unclear. We examined the contribution of Fc receptors in the induction of nephrotoxic GN by establishing and analyzing mice deficient in the Fc receptor gamma chain (FcRgamma). Whereas all wild-type mice died from severe glomerulonephritis with hypernitremia by administration of anti-glomerular basement membrane (GBM) antibodies, all FcRgamma-deficient mice survived. Histologically, wild-type mice showed glomerular hypercellularity and thrombotic changes, whereas the renal tissue in FcRgamma-deficient mice was almost intact. Deposition of anti-GBM antibody as well as complement components in the GBM were equally observed in both wild-type and knockout mice. These results demonstrate that the triggering of this type of glomerulonephritis is completely dependent on FcR+ cells. PMID:9739057

  4. Melanocortin 1 Receptor Deficiency Promotes Atherosclerosis in Apolipoprotein E-/- Mice.

    PubMed

    Rinne, Petteri; Kadiri, James J; Velasco-Delgado, Mauricio; Nuutinen, Salla; Viitala, Miro; Hollmén, Maija; Rami, Martina; Savontaus, Eriika; Steffens, Sabine

    2018-02-01

    The MC1-R (melanocortin 1 receptor) is expressed by monocytes and macrophages where it mediates anti-inflammatory actions. MC1-R also protects against macrophage foam cell formation primarily by promoting cholesterol efflux through the ABCA1 (ATP-binding cassette transporter subfamily A member 1) and ABCG1 (ATP-binding cassette transporter subfamily G member 1). In this study, we aimed to investigate whether global deficiency in MC1-R signaling affects the development of atherosclerosis. Apoe -/- (apolipoprotein E deficient) mice were crossed with recessive yellow (Mc1r e/e ) mice carrying dysfunctional MC1-R and fed a high-fat diet to induce atherosclerosis. Apoe -/- Mc1r e/e mice developed significantly larger atherosclerotic lesions in the aortic sinus and in the whole aorta compared with Apoe -/- controls. In terms of plaque composition, MC1-R deficiency was associated with less collagen and smooth muscle cells and increased necrotic core, indicative of more vulnerable lesions. These changes were accompanied by reduced Abca1 and Abcg1 expression in the aorta. Furthermore, Apoe -/- Mc1r e/e mice showed a defect in bile acid metabolism that aggravated high-fat diet-induced hypercholesterolemia and hepatic lipid accumulation. Flow cytometric analysis of leukocyte profile revealed that dysfunctional MC1-R enhanced arterial accumulation of classical Ly6C high monocytes and macrophages, effects that were evident in mice fed a normal chow diet but not under high-fat diet conditions. In support of enhanced arterial recruitment of Ly6C high monocytes, these cells had increased expression of L-selectin and P-selectin glycoprotein ligand 1. The present study highlights the importance of MC1-R in the development of atherosclerosis. Deficiency in MC1-R signaling exacerbates atherosclerosis by disturbing cholesterol handling and by increasing arterial monocyte accumulation. © 2017 The Authors.

  5. Increased vascular sympathetic modulation in mice with Mas receptor deficiency.

    PubMed

    Rabello Casali, Karina; Ravizzoni Dartora, Daniela; Moura, Marina; Bertagnolli, Mariane; Bader, Michael; Haibara, Andrea; Alenina, Natalia; Irigoyen, Maria Claudia; Santos, Robson A

    2016-01-01

    The angiotensin-converting enzyme 2 (ACE2)/angiotensin (Ang)-(1-7)/Mas axis could modulate the heart rate (HR) and blood pressure variabilities (BPV) which are important predictors of cardiovascular risk and provide information about the autonomic modulation of the cardiovascular system. Therefore we investigated the effect of Mas deficiency on autonomic modulation in wild type and Mas-knockout (KO) mice. Blood pressure was recorded at high sample rate (4000 Hz). Stationary sequences of 200-250 beats were randomly chosen. Frequency domain analysis of HR and BPV was performed with an autoregressive algorithm on the pulse interval sequences and on respective systolic sequences. The KO group presented an increase of systolic arterial pressure (SAP; 127.26±11.20 vs 135.07±6.98 mmHg), BPV (3.54±1.54 vs 5.87±2.12 mmHg(2)), and low-frequency component of systolic BPV (0.12±0.11 vs 0.47±0.34 mmHg(2)). The deletion of Mas receptor is associated with an increase of SAP and with an increased BPV, indicating alterations in autonomic control. Increase of sympathetic vascular modulation in absence of Mas evidences the important role of Ang-(1-7)/Mas on cardiovascular regulation. Moreover, the absence of significant changes in HR and HRV can indicate an adaptation of autonomic cardiac balance. Our results suggest that the Ang-(1-7)/Mas axis seems more important in autonomic modulation of arterial pressure than HR. © The Author(s) 2016.

  6. Increased vascular sympathetic modulation in mice with Mas receptor deficiency

    PubMed Central

    Rabello Casali, Karina; Ravizzoni Dartora, Daniela; Moura, Marina; Bertagnolli, Mariane; Bader, Michael; Haibara, Andrea; Alenina, Natalia; Irigoyen, Maria Claudia; Santos, Robson A

    2016-01-01

    Introduction: The angiotensin-converting enzyme 2 (ACE2)/angiotensin (Ang)-(1–7)/Mas axis could modulate the heart rate (HR) and blood pressure variabilities (BPV) which are important predictors of cardiovascular risk and provide information about the autonomic modulation of the cardiovascular system. Therefore we investigated the effect of Mas deficiency on autonomic modulation in wild type and Mas-knockout (KO) mice. Methods: Blood pressure was recorded at high sample rate (4000 Hz). Stationary sequences of 200–250 beats were randomly chosen. Frequency domain analysis of HR and BPV was performed with an autoregressive algorithm on the pulse interval sequences and on respective systolic sequences. Results: The KO group presented an increase of systolic arterial pressure (SAP; 127.26±11.20 vs 135.07±6.98 mmHg), BPV (3.54±1.54 vs 5.87±2.12 mmHg2), and low-frequency component of systolic BPV (0.12±0.11 vs 0.47±0.34 mmHg2). Conclusions: The deletion of Mas receptor is associated with an increase of SAP and with an increased BPV, indicating alterations in autonomic control. Increase of sympathetic vascular modulation in absence of Mas evidences the important role of Ang-(1–7)/Mas on cardiovascular regulation. Moreover, the absence of significant changes in HR and HRV can indicate an adaptation of autonomic cardiac balance. Our results suggest that the Ang-(1–7)/Mas axis seems more important in autonomic modulation of arterial pressure than HR. PMID:27080540

  7. Group 1B phospholipase A₂ inactivation suppresses atherosclerosis and metabolic diseases in LDL receptor-deficient mice.

    PubMed

    Hollie, Norris I; Konaniah, Eddy S; Goodin, Colleen; Hui, David Y

    2014-06-01

    Previous studies have shown that inactivation of the group 1B phospholipase A2 (Pla2g1b) suppresses diet-induced obesity, hyperglycemia, insulin resistance, and hyperlipidemia in C57BL/6 mice. A possible influence of Pla2g1b inactivation on atherosclerosis has not been addressed previously. The current study utilized LDL receptor-deficient (Ldlr(-/-)) mice with plasma lipid levels and distribution similar to hyperlipidemic human subjects as a preclinical animal model to test the effectiveness of Pla2g1b inactivation on atherosclerosis. The Pla2g1b(+/+)Ldlr(-/-) and Pla2g1b(-/-)Ldlr(-/-) mice were fed a low fat chow diet or a hypercaloric diet with 58.5 kcal% fat and 25 kcal% sucrose for 10 weeks. Minimal differences were observed between Pla2g1b(+/+)Ldlr(-/-) and Pla2g1b(-/-)Ldlr(-/-) mice when the animals were maintained on the low fat chow diet. However, when the animals were maintained on the hypercaloric diet, the Pla2g1(+/+)Ldlr(-/-) mice showed the expected body weight gain but the Pla2g1b(-/-)Ldlr(-/-) mice were resistant to diet-induced body weight gain. The Pla2g1b(-/-)Ldlr(-/-) mice also displayed lower fasting glucose, insulin, and plasma lipid levels compared to the Pla2g1b(+/+)Ldlr(-/-) mice, which displayed robust hyperglycemia, hyperinsulinemia, and hyperlipidemia in response to the hypercaloric diet. Importantly, atherosclerotic lesions in the aortic roots were also reduced 7-fold in the Pla2g1b(-/-)Ldlr(-/-) mice. The effectiveness of Pla2g1b inactivation to suppress diet-induced body weight gain and reduce diabetes and atherosclerosis in LDL receptor-deficient mice suggests that pharmacological inhibition of Pla2g1b may be a viable strategy to decrease diet-induced obesity and the risk of diabetes and atherosclerosis in humans. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  8. Epizootic hemorrhagic disease virus infection of type I interferon receptor deficient mice.

    PubMed

    Eschbaumer, Michael; Keller, Markus; Beer, Martin; Hoffmann, Bernd

    2012-03-23

    Type I interferon receptor deficient (IFNAR(-/-)) mice were infected with an Israeli isolate of serotype 7 of epizootic hemorrhagic disease virus (EHDV; Orbivirus, Reoviridae). Two out of two mice that received 5×10(5) 50% tissue culture infectious doses (TCID(50)) by intraperitoneal injection died or were euthanized in a moribund state on day 5 after infection. One mouse out of three that had been inoculated with 5×10(2) TCID(50) died on day 7 while the remaining mice did not show any clinical signs and survived until the end of the experiment. Spleens of all dead mice were highly positive in an EHDV real-time RT-PCR (quantification cycle values ≤15) and contained ≥10(5.8) TCID(50) of virus per ml of homogenate. The viral RNA content and virus titer in the spleens of the two surviving mice, on the other hand, were over 100-fold lower. Different from data reported for BTV, the outcome of EHDV infection of IFNAR(-/-) mice is dose-dependent and subclinical infections can occur. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Excessive penile norepinephrine level underlies impaired erectile function in adenosine A1 receptor deficient mice.

    PubMed

    Ning, Chen; Qi, Lin; Wen, Jiaming; Zhang, Yujin; Zhang, Weiru; Wang, Wei; Blackburn, Michael; Kellems, Rodney; Xia, Yang

    2012-10-01

    Penile erection is a complex neurovascular physiological event controlled by multiple factors and signaling pathways. A considerable amount of evidence indicates that adenosine plays a significant role in cavernosal smooth muscle relaxation. However, the specific role of adenosine and its receptors in erectile physiology and pathology is not fully understood. To determine the role of the adenosine A1 receptor (ADORA1) in penile erection. Adenosine A1 receptor deficient (Adora1-/-) mice and aged-matched wild-type (WT) mice were utilized. We evaluated the in vivo erectile function by measuring the intracavernosal pressure (ICP) in response to cavernous nerve stimulation (CNS). Enzyme-linked immunosorbent assay was used to measure the norepinephrine (NE) plasma concentration in the corpus cavernosum and systemic circulation. We also evaluated the myosin light chain phosphorylation (p-MLC) in penile tissue pre- and post-CNS. The main outcome measurement of this research was the evaluation of in vivo erectile response to CNS by measuring the ICP in Adora1-/- mice and WT mice and to identify the localization and specific neuron types of ADORA1 expression by dual immunostaining and immunofluorescence co-localization. In vivo, both the ratio of CNS-induced Maximum ICP to mean arterial pressure and CNS-induced slope in Adora1-/- mice were significantly lower than WT mice. At the cellular level in penile tissue, we determined that ADORA1 was highly abundant in neuronal cells. During penile erection, Adora1-/- mice exhibited a higher level of NE plasma concentration in the penis than WT mice. And WT mice had a significantly greater reduction in p-MLC compared to Adora1-/- mice. Our results show that ADORA1 is enriched on neuron cells where it functions to control NE release. Activation of this receptor during penile erection results in reduced NE release and reduced cavernosal smooth muscle contraction, therefore facilitating penile erection. © 2012 International Society for

  10. Enhanced acetylcholine release in the hippocampus of cannabinoid CB1 receptor-deficient mice

    PubMed Central

    Kathmann, Markus; Weber, Bernd; Zimmer, Andreas; Schlicker, Eberhard

    2001-01-01

    We examined whether acetylcholine release in the hippocampus and striatum and noradrenaline release in the hippocampus is altered in CB1 receptor-deficient mice. The electrically evoked tritium overflow from hippocampal slices preincubated with [3H]-choline was increased by about 100% in CB1−/− compared to CB1+/+ mice whereas the electrically evoked tritium overflow from striatal slices preincubated with [3H]-choline and from hippocampal slices preincubated with [3H]-noradrenaline did not differ. The cannabinoid receptor agonist, WIN 55,212-2, inhibited, and the CB1 receptor antagonist, SR 141716, facilitated, the evoked tritium overflow from hippocampal slices (preincubated with [3H]-choline) from CB1+/+ as opposed to CB1−/− mice. Both drugs did not affect the evoked tritium overflow from striatal slices (preincubated with [3H]-choline) and from hippocampal slices (preincubated with [3H]-noradrenaline) from CB1+/+ and CB1−/− mice. The selective increase in acetylcholine release in CB1−/− mice may indicate that the presynaptic CB1 receptors on the cholinergic neurones of the mouse hippocampus are tonically activated and/or constitutively active in vivo. PMID:11250865

  11. Citrullus lanatus `Sentinel' (Watermelon) Extract Reduces Atherosclerosis in LDL Receptor Deficient Mice

    PubMed Central

    Poduri, Aruna; Rateri, Debra L.; Saha, Shubin K.; Saha, Sibu; Daugherty, Alan

    2012-01-01

    Watermelon (Citrullus lanatus or C. lanatus) has many potentially bioactive compounds including citrulline, which may influence atherosclerosis. In this study, we determined the effects of C. lanatus, provided as an extract of the cultivar `sentinel', on hypercholesterolemia-induced atherosclerosis in mice. Male LDL receptor deficient mice at 8 weeks old were given either C. lanatus `sentinel' extract (2% vol/vol; n=10) or a mixture of matching carbohydrates (2% vol/vol; n=8) as the control in drinking water, while fed a saturated fat-enriched diet for 12 weeks ad libitum. Mice consuming C. lanatus `sentinel' extract had significantly increased plasma citrulline concentrations. Systolic blood pressure was comparable between the two groups. Consumption of C. lanatus `sentinel' extract led to lower body weight and fat mass without influencing lean mass. There were no differences in food and water intake, and urine output between the two groups. C. lanatus `sentinel' extract administration decreased plasma cholesterol concentrations that were attributed to reductions of intermediate/low density lipoprotein cholesterol. Plasma concentrations of MCP-1 and IFN-γ were decreased and IL-10 increased in mice consuming C. lanatus `sentinel' extract. Intake of C. lanatus `sentinel' extract resulted in reductions of atherosclerosis in both aortic arch and thoracic regions. In conclusion, consumption of C. lanatus `sentinel' extract led to reduced body weight gain, decreased plasma cholesterol concentrations, improved homeostasis of pro- and anti-inflammatory cytokines, and attenuated development of atherosclerosis without affecting systolic blood pressure in hypercholesterolemic mice. PMID:22902326

  12. Mas receptor deficiency exacerbates lipopolysaccharide-induced cerebral and systemic inflammation in mice.

    PubMed

    Oliveira-Lima, Onésia C; Pinto, Mauro C X; Duchene, Johan; Qadri, Fatimunnisa; Souza, Laura L; Alenina, Natalia; Bader, Michael; Santos, Robson A S; Carvalho-Tavares, Juliana

    2015-12-01

    Beyond the classical actions of the renin-angiotensin system on the regulation of cardiovascular homeostasis, several studies have shown its involvement in acute and chronic inflammation. The G protein-coupled receptor Mas is a functional binding site for the angiotensin-(1-7); however, its role in the immune system has not been fully elucidated. In this study, we evaluated the effect of genetic deletion of Mas receptor in lipopolysaccharide (LPS)-induced systemic and cerebral inflammation in mice. Inflammatory response was triggered in Mas deficient (Mas(-/-)) and C57BL/6 wild-type (WT) mice (8-12 weeks-old) by intraperitoneal injection of LPS (5 mg/kg). Mas(-/-) mice presented more intense hypothermia compared to WT mice 24 h after LPS injection. Systemically, the bone marrow of Mas(-/-) mice contained a lower number of neutrophils and monocytes 3 h and 24 h after LPS injection, respectively. The plasma levels of inflammatory mediators KC, MCP-1 and IL-10 were higher in Mas(-/-) mice 24 h after LPS injection in comparison to WT. In the brain, Mas(-/-) animals had a significant increase in the number of adherent leukocytes to the brain microvasculature compared to WT mice, as well as, increased number of monocytes and neutrophils recruited to the pia-mater. The elevated number of adherent leukocytes on brain microvasculature in Mas(-/-) mice was associated with increased expression of CD11b - the alpha-subunit of the Mac-1 integrin - in bone marrow neutrophils 3h after LPS injection, and with increased brain levels of chemoattractants KC, MIP-2 and MCP-1, 24 h later. In conclusion, we demonstrated that Mas receptor deficiency results in exacerbated inflammation in LPS-challenged mice, which suggest a potential role for the Mas receptor as a regulator of systemic and brain inflammatory response induced by LPS. Copyright © 2015 Elsevier GmbH. All rights reserved.

  13. Oats (Avena sativa) reduce atherogenesis in LDL-receptor-deficient mice.

    PubMed

    Andersson, K E; Svedberg, K A; Lindholm, M W; Oste, R; Hellstrand, P

    2010-09-01

    The cholesterol-lowering properties of oats, largely ascribed to its contents of soluble fibers, beta-glucans, are well established, whereas effects on atherogenesis are less well elucidated. Oats also contains components with reported antioxidant and anti-inflammatory effects that may affect atherogenesis. In this work we examined effects of oat bran on plasma cholesterol, markers of inflammation, eNOS expression and development of atherosclerosis in LDL-receptor-deficient (LDLr(-/-)) mice. Female LDLr(-/-) mice were fed Western diet+/-oat bran. Two concentrations of oat bran (40 and 27%) were compared regarding effects on plasma lipids. There was a dose-dependent reduction of plasma cholesterol by 42 and 20% with 40 and 27% oat bran, respectively. Both concentrations also lowered plasma triglycerides (by 45 and 33%) and relative levels of plasma LDL+VLDL. The reduction of plasma lipids was accompanied by increased faecal excretion of cholesterol and bile acids. Oat bran (40%) efficiently reduced atherosclerotic lesion area in the descending aorta (-77%) and aortic root (-33%). Plasma levels of fibrinogen and soluble vascular cell adhesion molecule-1 (VCAM-1) were significantly lower, and immunofluorescence of aortic sections revealed a 75% lower expression of VCAM-1 in oat-fed mice. The expression of eNOS protein in the aortic wall was increased in mice fed oat bran. Oat bran supplemented to a Western diet lowers plasma cholesterol, reduces levels of some inflammatory markers, increases eNOS expression and inhibits atherosclerotic lesion development in LDLr(-/-) mice. It remains to be investigated which components in oats contribute to these effects. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  14. Citrullus lanatus 'sentinel' (watermelon) extract reduces atherosclerosis in LDL receptor-deficient mice.

    PubMed

    Poduri, Aruna; Rateri, Debra L; Saha, Shubin K; Saha, Sibu; Daugherty, Alan

    2013-05-01

    Watermelon (Citrullus lanatus or C. lanatus) has many potentially bioactive compounds including citrulline, which may influence atherosclerosis. In this study, we determined the effects of C. lanatus, provided as an extract of the cultivar 'sentinel,' on hypercholesterolemia-induced atherosclerosis in mice. Male low-density lipoprotein receptor-deficient mice at 8 weeks old were given either C. lanatus 'sentinel' extract (2% vol/vol; n=10) or a mixture of matching carbohydrates (2% vol/vol; n=8) as the control in drinking water while being fed a saturated fat-enriched diet for 12 weeks ad libitum. Mice consuming C. lanatus 'sentinel' extract had significantly increased plasma citrulline concentrations. Systolic blood pressure was comparable between the two groups. Consumption of C. lanatus 'sentinel' extract led to lower body weight and fat mass without influencing lean mass. There were no differences in food and water intake and in urine output between the two groups. C. lanatus 'sentinel' extract administration decreased plasma cholesterol concentrations that were attributed to reductions of intermediate-/low-density lipoprotein cholesterol. Plasma concentrations of monocyte chemoattractant protein-1 and interferon-gamma were decreased and those of interleukin-10 were increased in mice consuming C. lanatus 'sentinel' extract. Intake of C. lanatus 'sentinel' extract resulted in reductions of atherosclerosis in both aortic arch and thoracic regions. In conclusion, consumption of C. lanatus 'sentinel' extract led to reduced body weight gain, decreased plasma cholesterol concentrations, improved homeostasis of pro- and anti-inflammatory cytokines, and attenuated development of atherosclerosis without affecting systolic blood pressure in hypercholesterolemic mice. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Amygdalin ameliorates the progression of atherosclerosis in LDL receptor-deficient mice

    PubMed Central

    Lv, Jianzhen; Xiong, Wen; Lei, Tiantian; Wang, Hailian; Sun, Minghan; Hao, Erwei; Wang, Zhiping; Huang, Xiaoqi; Deng, Shaoping; Deng, Jiagang; Wang, Yi

    2017-01-01

    Previous studies have demonstrated that regulatory T cells (Tregs) are pivotal in the regulation of T cell-mediated immune responses in atherosclerosis, a chronic autoimmune-like disease. In the authors' previous studies, it was demonstrated that amygdalin ameliorated atherosclerosis by the regulation of Tregs in apolipoprotein E-deficient (ApoE−/−) mice. Therefore, the aim of the present study was to investigate the therapeutic effect of amygdalin on low-density lipoprotein (LDL) receptor deficient (LDLR−/−) mice, and to examine its immune regulatory function by the stimulation of Tregs. To establish an atherosclerosis mouse model, the LDLR−/− mice were fed a high fat and high cholesterol diet then the total plasma cholesterol, triglyceride, LDL and chemokines levels were measured by an ELISA. Following sacrificing the mice, the upper sections of the aorta were stained by hematoxylin and eosin, and Oil red O to assess the plaque area. Then western blotting and reverse transcription polymerase chain reactions were performed to analysis the expression levels of cluster of differentiation 68, monocyte chemoattractant protein-1, matrix metalloproteinase (MMP)-2, MMP-9 and forkhead box P3 (Foxp3). To further confirm the activation of FOXP3 by amygdalin, lentiviruses carrying Foxp3 shRNA were injected into the mice, and the serum cytokines levels were measured by ELISA. Following feeding of the mice with a high-fat/high-cholesterol diet, the LDLR−/− mice demonstrated comparatively higher levels of triglyceride, total cholesterol and LDL, compared with levels in the amygdalin-treated mice. By comparing the vessel area, lumen area, plaque area, and percentage aortic plaque coverage, the effects of amygdalin on pre-existing lesions were assessed. In addition, the levels of CD68, monocyte chemoattractant protein-1, MMP-2 and MMP-9 were analyzed, and analysis of the expression of interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α indicated that the

  16. Endogenous Androgen Deficiency Enhances Diet-Induced Hypercholesterolemia and Atherosclerosis in Low-Density Lipoprotein Receptor-Deficient Mice

    PubMed Central

    Hatch, Nicholas W.; Srodulski, Sarah J.; Chan, Huei-Wei; Zhang, Xuan; Tannock, Lisa R.; King, Victoria L.

    2012-01-01

    Background Despite numerous clinical and animal studies, the role of sex steroid hormones on lipoprotein metabolism and atherosclerosis remain controversial. Objective We sought to determine the effects of endogenous estrogen and testosterone on lipoprotein levels and atherosclerosis using mice fed a low-fat diet with no added cholesterol. Methods Male and female low-density lipoprotein receptor-deficient mice were fed an open stock low-fat diet (10% of kcals from fat) for 2, 4, or 17 weeks. Ovariectomy, orchidectomy, or sham surgeries were performed to evaluate the effects of the presence or absence of endogenous hormones on lipid levels, lipoprotein distribution, and atherosclerosis development. Results Female mice fed the study diet for 17 weeks had a marked increase in levels of total cholesterol, triglycerides, apolipoprotein-B containing lipoproteins, and atherosclerosis compared with male mice. Surprisingly, ovariectomy in female mice had no effect on any of these parameters. In contrast, castration of male mice markedly increased total cholesterol concentrations, triglycerides, apolipoprotein B-containing lipoproteins, and atherosclerotic lesion formation compared with male and female mice. Conclusions These data suggest that endogenous androgens protect against diet-induced increases in cholesterol concentrations, formation of proatherogenic lipoproteins, and atherosclerotic lesions formation. Conversely orchidectomy, which decreases androgen concentrations, promotes increases in cholesterol concentrations, proatherogenic lipoprotein formation, and atherosclerotic lesion formation in lowdensity lipoprotein receptor-deficient mice in response to a low-fat diet. PMID:22981166

  17. Whole-Body Vibration Mimics the Metabolic Effects of Exercise in Male Leptin Receptor-Deficient Mice.

    PubMed

    McGee-Lawrence, Meghan E; Wenger, Karl H; Misra, Sudipta; Davis, Catherine L; Pollock, Norman K; Elsalanty, Mohammed; Ding, Kehong; Isales, Carlos M; Hamrick, Mark W; Wosiski-Kuhn, Marlena; Arounleut, Phonepasong; Mattson, Mark P; Cutler, Roy G; Yu, Jack C; Stranahan, Alexis M

    2017-05-01

    Whole-body vibration (WBV) has gained attention as a potential exercise mimetic, but direct comparisons with the metabolic effects of exercise are scarce. To determine whether WBV recapitulates the metabolic and osteogenic effects of physical activity, we exposed male wild-type (WT) and leptin receptor-deficient (db/db) mice to daily treadmill exercise (TE) or WBV for 3 months. Body weights were analyzed and compared with WT and db/db mice that remained sedentary. Glucose and insulin tolerance testing revealed comparable attenuation of hyperglycemia and insulin resistance in db/db mice following TE or WBV. Both interventions reduced body weight in db/db mice and normalized muscle fiber diameter. TE or WBV also attenuated adipocyte hypertrophy in visceral adipose tissue and reduced hepatic lipid content in db/db mice. Although the effects of leptin receptor deficiency on cortical bone structure were not eliminated by either intervention, exercise and WBV increased circulating levels of osteocalcin in db/db mice. In the context of increased serum osteocalcin, the modest effects of TE and WBV on bone geometry, mineralization, and biomechanics may reflect subtle increases in osteoblast activity in multiple areas of the skeleton. Taken together, these observations indicate that WBV recapitulates the effects of exercise on metabolism in type 2 diabetes.

  18. Validity of leptin receptor-deficiency (db/db) type 2 diabetes mellitus mice as a model of secondary osteoporosis

    NASA Astrophysics Data System (ADS)

    Huang, Le; You, Yong-Ke; Zhu, Tracy Y.; Zheng, Li-Zhen; Huang, Xiao-Ru; Chen, Hai-Yong; Yao, Dong; Lan, Hui-Yao; Qin, Ling

    2016-06-01

    This study aimed to evaluate the validation of the leptin receptor-deficient mice model for secondary osteoporosis associated with type 2 diabetes mellitus (T2DM) at bone micro-architectural level. Thirty three 36-week old male mice were divided into four groups: normal control (db/m) (n = 7), leptin receptor-deficient T2DM (db/db) (n = 8), human C-reactive protein (CRP) transgenic normal control (crp/db/m) (n = 7), and human CRP transgenic T2DM (crp/db/db) (n = 11). Lumber vertebrae (L5) and bilateral lower limbs were scanned by micro-CT to analyze trabecular and cortical bone quality. Right femora were used for three-point bending to analyze the mechanical properties. Trabecular bone quality at L5 was better in db/db or crp/db/db group in terms of bone mineral density (BMD), bone volume fraction, connectivity density, trabecular number and separation (all p < 0.05). However the indices measured at proximal tibia showed comparable trabecular BMD and microarchitecture among the four groups. Femur length in crp/db/db group was significantly shorter than db/m group (p < 0.05) and cortices were thinner in db/db and crp/db/db groups (p > 0.05). Maximum loading and energy yield in mechanical test were similar among groups while the elastic modulus in db/db and crp/db/db significantly lower than db/m. The leptin-receptor mice is not a proper model for secondary osteoporosis associated with T2DM.

  19. Effects of Saskatoon berry powder on monocyte adhesion to vascular wall of leptin receptor-deficient diabetic mice.

    PubMed

    Zhao, Ruozhi; Le, Khuong; Li, Wende; Ren, Song; Moghadasian, Mohammed H; Beta, Trust; Shen, Garry X

    2014-08-01

    Atherosclerotic cardiovascular complications are the leading cause of death in diabetic patients. Monocyte adhesion is an early event for atherogenesis. Previous studies demonstrated that dark-skin berries had cardiovascular protective effects. We hypothesize that Saskatoon berry (SB) powder may reduce monocyte adhesion in leptin receptor-deficient (db/db) diabetic mice. Wild-type and db/db mice were fed with chow or supplemented with SB powder. Anthocyanins in SB powder were identified using mass spectrometry. Mouse monocytes were incubated with mouse aorta. Monocyte adhesion was counted under microscopy. Inflammatory or metabolic markers in blood or tissue were analyzed using immunological or biochemical methods. SB powder significantly reduced monocyte adhesion to aorta from diabetic db/db mice compared to regular chow. The increased monocyte adhesion to aorta was normalized in db/db mice treated with ≥5% of SB powder for 4 weeks. Increased contents of Nicotinamide adenine dinucleotide phosphate oxidase (NADPH) oxidase-4, heat shock factor-1, monocyte chemotactic protein (MCP)-1, intracellular adhesion molecule (ICAM)-1, P-selectin, tumor necrosis factor-α, plasminogen activator inhibitor (PAI)-1 and urokinase plasminogen activator in aorta or heart apex, elevated plasma PAI-1 and MCP-1 were detected in db/db mice on chow compared to wild-type mice on the same diet; 5% SB powder inhibited the increases of inflammatory, fibrinolytic or stress regulators in aorta or heart apex of db/db mice. Monocyte adhesion positively correlated with blood glucose, cholesterol, body weight, heart MCP-1, PAI-1 or ICAM-1. The findings suggest that SB powder attenuated monocyte adhesion to aorta of db/db mice, which was potentially mediated through inhibiting the inflammatory, stress and/or fibrinolyic regulators. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Atherosclerosis and cardiac function assessment in low-density lipoprotein receptor-deficient mice undergoing body weight cycling.

    PubMed

    McMillen, T S; Minami, E; Leboeuf, R C

    2013-06-24

    Obesity has become an epidemic in many countries and is supporting a billion dollar industry involved in promoting weight loss through diet, exercise and surgical procedures. Because of difficulties in maintaining body weight reduction, a pattern of weight cycling often occurs (so called 'yo-yo' dieting) that may result in deleterious outcomes to health. There is controversy about cardiovascular benefits of yo-yo dieting, and an animal model is needed to better understand the contributions of major diet and body weight changes on heart and vascular functions. Our purpose is to determine the effects of weight cycling on cardiac function and atherosclerosis development in a mouse model. We used low-density lipoprotein receptor-deficient mice due to their sensitivity to metabolic syndrome and cardiovascular diseases when fed high-fat diets. Alternating ad libitum feeding of high-fat and low-fat (rodent chow) diets was used to instigate weight cycling during a 29-week period. Glucose tolerance and insulin sensitivity tests were done at 22 and 24 weeks, echocardiograms at 25 weeks and atherosclerosis and plasma lipoproteins assessed at 29 weeks. Mice subjected to weight cycling showed improvements in glucose homeostasis during the weight loss cycle. Weight-cycled mice showed a reduction in the severity of atherosclerosis as compared with high-fat diet-fed mice. However, atherosclerosis still persisted in weight-cycled mice as compared with mice fed rodent chow. Cardiac function was impaired in weight-cycled mice and matched with that of mice fed only the high-fat diet. This model provides an initial structure in which to begin detailed studies of diet, calorie restriction and surgical modifications on energy balance and metabolic diseases. This model also shows differential effects of yo-yo dieting on metabolic syndrome and cardiovascular diseases.

  1. Influence of fatty acids in maternal diet on atherogenesis in offspring of LDL receptor-deficient mice

    PubMed Central

    de Oliveira Cipriano Torres, Dilênia; Santos, Ana Célia Oliveira Dos; Silva, Amanda Karolina Soares E; de Moura, Patrícia Muniz Mendes Freire; Beltrão, Eduardo Isidoro Carneiro; Peixoto, Christina Alves

    2012-01-01

    Aims The present study investigated the effect of a maternal diet rich in omega-6 (E6D) or omega-9 (E9D) on atherogenesis in the offspring of mice. Main methods LDL receptor-deficient mice were fed a diet rich in either omega-6 (E6D) or omega-9 (E9D) for 45 days prior to mating and until the birth of the offspring, evaluating the effect on the offspring aorta in comparison to a standard diet (STD), by immunohistochemical analysis, morphometric analysis and electron microscopy. Key findings Hypercholesterolemic female mice fed E6D generated offspring with high levels of total cholesterol, triglycerides (TG) and CC-chemokine ligand 2/monocyte chemoattractant protein 1 (CCL2/ MCP-1) as well as a reduction in high-density lipoprotein. The ascending aorta of these animals exhibited an increase in arterial wall thickness as well as increased expression of CCL2/MCP-1 and vascular cell adhesion molecule 1. The ultrastructural analysis revealed severe alterations in endothelial cells. The offspring from mothers fed E9D exhibited a reduction in TG and an increase in low-density lipoprotein. The ultrastructural analysis revealed a well-preserved aortic endothelium in these animals. Significance The results suggest that hypercholesterolemic mothers feed a diet rich in omega-6 predispose their offspring to endothelial dysfunction. PMID:22328949

  2. Eicosapentaenoic acid ameliorates non-alcoholic steatohepatitis in a novel mouse model using melanocortin 4 receptor-deficient mice.

    PubMed

    Konuma, Kuniha; Itoh, Michiko; Suganami, Takayoshi; Kanai, Sayaka; Nakagawa, Nobutaka; Sakai, Takeru; Kawano, Hiroyuki; Hara, Mitsuko; Kojima, Soichi; Izumi, Yuichi; Ogawa, Yoshihiro

    2015-01-01

    Many attempts have been made to find novel therapeutic strategies for non-alcoholic steatohepatitis (NASH), while their clinical efficacy is unclear. We have recently reported a novel rodent model of NASH using melanocortin 4 receptor-deficient (MC4R-KO) mice, which exhibit the sequence of events that comprise hepatic steatosis, liver fibrosis, and hepatocellular carcinoma with obesity-related phenotypes. In the liver of MC4R-KO mice, there is a unique histological feature termed hepatic crown-like structures (hCLS), where macrophages interact with dead hepatocytes and fibrogenic cells, thereby accelerating inflammation and fibrosis. In this study, we employed MC4R-KO mice to examine the effect of highly purified eicosapentaenoic acid (EPA), a clinically available n-3 polyunsaturated fatty acid, on the development of NASH. EPA treatment markedly prevented the development of hepatocyte injury, hCLS formation and liver fibrosis along with lipid accumulation. EPA treatment was also effective even after MC4R-KO mice developed NASH. Intriguingly, improvement of liver fibrosis was accompanied by the reduction of hCLS formation and plasma kallikrein-mediated transforming growth factor-β activation. Moreover, EPA treatment increased the otherwise reduced serum concentrations of adiponectin, an adipocytokine with anti-inflammatory and anti-fibrotic properties. Collectively, EPA treatment effectively prevents the development and progression of NASH in MC4R-KO mice along with amelioration of hepatic steatosis. This study unravels a novel anti-fibrotic mechanism of EPA, thereby suggesting a clinical implication for the treatment of NASH.

  3. Antihypertensive effect of etamicastat in dopamine D2 receptor-deficient mice.

    PubMed

    Armando, Ines; Asico, Laureano D; Wang, Xiaoyan; Jones, John E; Serrão, Maria Paula; Cuevas, Santiago; Grandy, David K; Soares-da-Silva, Patricio; Jose, Pedro A

    2018-04-13

    Abnormalities of the D 2 R gene (DRD2) play a role in the pathogenesis of human essential hypertension; variants of the DRD2 have been reported to be associated with hypertension. Disruption of Drd2 (D 2 -/- ) in mice increases blood pressure. The hypertension of D 2 -/- mice has been related, in part, to increased sympathetic activity, renal oxidative stress, and renal endothelin B receptor (ETBR) expression. We tested in D 2 -/- mice the effect of etamicastat, a reversible peripheral inhibitor of dopamine-β-hydroxylase that reduces the biosynthesis of norepinephrine from dopamine and decreases sympathetic nerve activity. Blood pressure was measured in anesthetized D 2 -/- mice treated with etamicastat by gavage, (10 mg/kg), conscious D 2 -/- mice, and D 2 +/+ littermates, and mice with the D 2 R selectively silenced in the kidney, treated with etamicastat in the drinking water (10 mg/kg per day). Tissue and urinary catecholamines and renal expression of selected G protein-coupled receptors, enzymes related to the production of reactive oxygen species, and sodium transporters were also measured. Etamicastat decreased blood pressure both in anesthetized and conscious D 2 -/- mice and mice with renal-selective silencing of D 2 R to levels similar or close to those measured in D 2 +/+ littermates. Etamicastat decreased cardiac and renal norepinephrine and increased cardiac and urinary dopamine levels in D 2 -/- mice. It also normalized the increased renal protein expressions of ETBR, NADPH oxidase isoenzymes, and urinary 8-isoprostane, as well as renal NHE3 and NCC, and increased the renal expression of D 1 R but not D 5 R in D 2 -/- mice. In conclusion, etamicastat is effective in normalizing the increased blood pressure and some of the abnormal renal biochemical alterations of D 2 -/- mice.

  4. D4 receptor deficiency in mice has limited effects on impulsivity and novelty seeking.

    PubMed

    Helms, C M; Gubner, N R; Wilhelm, C J; Mitchell, S H; Grandy, D K

    2008-09-01

    Alleles of the human dopamine D(4) receptor (D(4)R) gene (DRD4.7) have repeatedly been found to correlate with novelty seeking, substance abuse, pathological gambling, and attention-deficit hyperactivity disorder (ADHD). If these various psychopathologies are a result of attenuated D(4)R-mediated signaling, mice lacking D(4)Rs (D(4)KO) should be more impulsive than wild-type (WT) mice and exhibit more novelty seeking. However, in our study, D(4)KO and WT mice showed similar levels of impulsivity as measured by delay discounting performance and response inhibition on a Go/No-go test, suggesting that D(4)R-mediated signaling may not affect impulsivity. D(4)KO mice were more active than WT mice in the first 5 min of a novel open field test, suggesting greater novelty seeking. For both genotypes, more impulsive mice habituated less in the novel open field. These data suggest that the absence of D(4)Rs is not sufficient to cause psychopathologies associated with heightened impulsivity and novelty seeking.

  5. Lethality and pathogenesis of airborne infection with filoviruses in A129 α/β -/- interferon receptor-deficient mice.

    PubMed

    Lever, Mark S; Piercy, Timothy J; Steward, Jackie A; Eastaugh, Lin; Smither, Sophie J; Taylor, Christopher; Salguero, Francisco J; Phillpotts, Robert J

    2012-01-01

    Normal immunocompetent mice are not susceptible to non-adapted filoviruses. There are therefore two strategies available to establish a murine model of filovirus infection: adaptation of the virus to the host or the use of genetically modified mice that are susceptible to the virus. A number of knockout (KO) strains of mice with defects in either their adaptive or innate immunity are susceptible to non-adapted filoviruses. In this study, A129 α/β -/- interferon receptor-deficient KO mice, strain A129 IFN-α/β -/-, were used to determine the lethality of a range of filoviruses, including Lake Victoria marburgvirus (MARV), Zaire ebolavirus (ZEBOV), Sudan ebolavirus (SEBOV), Reston ebolavirus (REBOV) and Côte d'Ivoire ebolavirus (CIEBOV), administered by using intraperitoneal (IP) or aerosol routes of infection. One hundred percent mortality was observed in all groups of KO mice that were administered with a range of challenge doses of MARV and ZEBOV by either IP or aerosol routes. Mean time to death for both routes was dose-dependent and ranged from 5.4 to 7.4 days in the IP injection challenge, and from 10.2 to 13 days in the aerosol challenge. The lethal dose (50 % tissue culture infective dose, TCID(50)) of ZEBOV for KO mice was <1 TCID(50) ml(-1) when administered by either the IP or aerosol route of infection; for MARV the lethal dose was <1 TCID(50) ml(-1) by the IP route of infection and <10 TCID(50) ml(-1) by the aerosol route. In contrast, there was no mortality after infection with SEBOV or REBOV by either IP or aerosol routes of infection; all the mice lost weight (~15 % loss of group mean body weight with SEBOV and ~7 % with REBOV) but recovered to their original weights by day 14 post-challenge. There was no mortality in mice administered with CIEBOV via the IP route of infection and no clinical signs of infection were observed. The progression of disease was faster following infection with ZEBOV than with MARV but ultimately both viruses caused

  6. Hyperphagia in male melanocortin 4 receptor deficient mice promotes growth independently of growth hormone

    PubMed Central

    Tan, H. Y.; Huang, L.; Cowley, M.; Veldhuis, J. D.; Chen, C.

    2016-01-01

    Key points Loss of function of the melanocortin 4 receptor (MC4R) results in hyperphagia, obesity and increased growth.Despite knowing that MC4Rs control food intake, we are yet to understand why defects in the function of the MC4R receptor contribute to rapid linear growth.We show that hyperphagia following germline loss of MC4R in male mice promotes growth while suppressing the growth hormone–insulin‐like growth factor‐1 (GH–IGF‐1) axis.We propose that hyperinsulinaemia promotes growth while suppressing the GH–IGF‐1 axis.It is argued that physiological responses essential to maintain energy flux override conventional mechanisms of pubertal growth to promote the storage of excess energy while ensuring growth. Abstract Defects in melanocortin‐4‐receptor (MC4R) signalling result in hyperphagia, obesity and increased growth. Clinical observations suggest that loss of MC4R function may enhance growth hormone (GH)‐mediated growth, although this remains untested. Using male mice with germline loss of the MC4R, we assessed pulsatile GH release and insulin‐like growth factor‐1 (IGF‐1) production and/or release relative to pubertal growth. We demonstrate early‐onset suppression of GH release in rapidly growing MC4R deficient (MC4RKO) mice, confirming that increased linear growth in MC4RKO mice does not occur in response to enhanced activation of the GH–IGF‐1 axis. The progressive suppression of GH release in MC4RKO mice occurred alongside increased adiposity and the progressive worsening of hyperphagia‐associated hyperinsulinaemia. We next prevented hyperphagia in MC4RKO mice through restricting calorie intake in these mice to match that of wild‐type (WT) littermates. Pair feeding of MC4RKO mice did not prevent increased adiposity, but attenuated hyperinsulinaemia, recovered GH release, and normalized linear growth rate to that seen in pair‐fed WT littermate controls. We conclude that the suppression of GH release in MC4RKO mice occurs

  7. Hyperphagia in male melanocortin 4 receptor deficient mice promotes growth independently of growth hormone.

    PubMed

    Tan, H Y; Steyn, F J; Huang, L; Cowley, M; Veldhuis, J D; Chen, C

    2016-12-15

    Loss of function of the melanocortin 4 receptor (MC4R) results in hyperphagia, obesity and increased growth. Despite knowing that MC4Rs control food intake, we are yet to understand why defects in the function of the MC4R receptor contribute to rapid linear growth. We show that hyperphagia following germline loss of MC4R in male mice promotes growth while suppressing the growth hormone-insulin-like growth factor-1 (GH-IGF-1) axis. We propose that hyperinsulinaemia promotes growth while suppressing the GH-IGF-1 axis. It is argued that physiological responses essential to maintain energy flux override conventional mechanisms of pubertal growth to promote the storage of excess energy while ensuring growth. Defects in melanocortin-4-receptor (MC4R) signalling result in hyperphagia, obesity and increased growth. Clinical observations suggest that loss of MC4R function may enhance growth hormone (GH)-mediated growth, although this remains untested. Using male mice with germline loss of the MC4R, we assessed pulsatile GH release and insulin-like growth factor-1 (IGF-1) production and/or release relative to pubertal growth. We demonstrate early-onset suppression of GH release in rapidly growing MC4R deficient (MC4RKO) mice, confirming that increased linear growth in MC4RKO mice does not occur in response to enhanced activation of the GH-IGF-1 axis. The progressive suppression of GH release in MC4RKO mice occurred alongside increased adiposity and the progressive worsening of hyperphagia-associated hyperinsulinaemia. We next prevented hyperphagia in MC4RKO mice through restricting calorie intake in these mice to match that of wild-type (WT) littermates. Pair feeding of MC4RKO mice did not prevent increased adiposity, but attenuated hyperinsulinaemia, recovered GH release, and normalized linear growth rate to that seen in pair-fed WT littermate controls. We conclude that the suppression of GH release in MC4RKO mice occurs independently of increased adipose mass, and is a

  8. Melanocortin 1 Receptor Deficiency Promotes Atherosclerosis in Apolipoprotein E−/− Mice

    PubMed Central

    Kadiri, James J.; Velasco-Delgado, Mauricio; Nuutinen, Salla; Viitala, Miro; Hollmén, Maija; Rami, Martina; Savontaus, Eriika; Steffens, Sabine

    2018-01-01

    Objective— The MC1-R (melanocortin 1 receptor) is expressed by monocytes and macrophages where it mediates anti-inflammatory actions. MC1-R also protects against macrophage foam cell formation primarily by promoting cholesterol efflux through the ABCA1 (ATP-binding cassette transporter subfamily A member 1) and ABCG1 (ATP-binding cassette transporter subfamily G member 1). In this study, we aimed to investigate whether global deficiency in MC1-R signaling affects the development of atherosclerosis. Approach and Results— Apoe−/− (apolipoprotein E deficient) mice were crossed with recessive yellow (Mc1re/e) mice carrying dysfunctional MC1-R and fed a high-fat diet to induce atherosclerosis. Apoe−/− Mc1re/e mice developed significantly larger atherosclerotic lesions in the aortic sinus and in the whole aorta compared with Apoe−/− controls. In terms of plaque composition, MC1-R deficiency was associated with less collagen and smooth muscle cells and increased necrotic core, indicative of more vulnerable lesions. These changes were accompanied by reduced Abca1 and Abcg1 expression in the aorta. Furthermore, Apoe−/− Mc1re/e mice showed a defect in bile acid metabolism that aggravated high-fat diet–induced hypercholesterolemia and hepatic lipid accumulation. Flow cytometric analysis of leukocyte profile revealed that dysfunctional MC1-R enhanced arterial accumulation of classical Ly6Chigh monocytes and macrophages, effects that were evident in mice fed a normal chow diet but not under high-fat diet conditions. In support of enhanced arterial recruitment of Ly6Chigh monocytes, these cells had increased expression of L-selectin and P-selectin glycoprotein ligand 1. Conclusions— The present study highlights the importance of MC1-R in the development of atherosclerosis. Deficiency in MC1-R signaling exacerbates atherosclerosis by disturbing cholesterol handling and by increasing arterial monocyte accumulation. PMID:29284608

  9. Myeloid interferon-γ receptor deficiency does not affect atherosclerosis in LDLR(-/-) mice.

    PubMed

    Boshuizen, Marieke C S; Neele, Annette E; Gijbels, Marion J J; van der Velden, Saskia; Hoeksema, Marten A; Forman, Ruth A; Muller, Werner; Van den Bossche, Jan; de Winther, Menno P J

    2016-03-01

    Atherosclerosis is a chronic lipid-driven inflammatory disease of the arterial wall. Interferon gamma (IFNγ) is an important immunomodulatory cytokine and a known pro-atherosclerotic mediator. However, cell-specific targeting of IFNγ or its signaling in atherosclerosis development has not been studied yet. As macrophages are important IFNγ targets, we here addressed the involvement of myeloid IFNγ signaling in murine atherosclerosis. Bone marrow was isolated from interferon gamma receptor 2 chain (IFNγR2) wildtype and myeloid IFNγR2 deficient mice and injected into lethally irradiated LDLR(-/-) mice. After recovery mice were put on a high fat diet for 10 weeks after which atherosclerotic lesion analysis was performed. In addition, the accompanying liver inflammation was assessed. Even though absence of myeloid IFNγ signaling attenuated the myeloid IFNγ response, no significant differences in atherosclerotic lesion size or phenotype were found. Also, when examining the liver inflammatory state no effects of IFNγR2 deficiency could be observed. Overall, our data argue against a role for myeloid IFNγR2 in atherosclerosis development. Since myeloid IFNγ signaling seems to be nonessential throughout atherogenesis, it is important to understand the mechanisms by which IFNγ acts in atherogenesis. In the future new studies should be performed considering other cell-specific targets. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Nogo-B receptor deficiency causes cerebral vasculature defects during embryonic development in mice

    PubMed Central

    Rana, Ujala; Liu, Zhong; Kumar, Suresh N.; Zhao, Baofeng; Hu, Wenquan; Bordas, Michelle; Cossette, Stephanie; Szabo, Sara; Foeckler, Jamie; Weiler, Hartmut; Chrzanowska-Wodnicka, Magdalena; Holtz, Mary L.; Misra, Ravindra P.; Salato, Valerie; North, Paula; Ramchandran, Ramani; Miao, Qing Robert

    2016-01-01

    Nogo-B receptor (NgBR) was identified as a receptor specific for Nogo-B. Our previous work has shown that Nogo-B and its receptor (NgBR) are essential for chemotaxis and morphogenesis of endothelial cells in vitro and intersomitic vessel formation via Akt pathway in zebrafish. Here, we further demonstrated the roles of NgBR in regulating vasculature development in mouse embryo and primitive blood vessel formation in embryoid body culture systems, respectively. Our results showed that NgBR homozygous knockout mice are embryonically lethal at E7.5 or earlier, and Tie2Cre-mediated endothelial cell-specific NgBR knockout (NgBR ecKO) mice die at E11.5 and have severe blood vessel assembly defects in embryo. In addition, mutant embryos exhibit dilation of cerebral blood vessel, resulting in thin-walled endothelial caverns. The similar vascular defects also were detected in Cdh5(PAC)-CreERT2 NgBR inducible ecKO mice. Murine NgBR gene-targeting embryonic stem cells (ESC) were generated by homologous recombination approaches. Homozygous knockout of NgBR in ESC results in cell apoptosis. Heterozygous knockout of NgBR does not affect ESC cell survival, but reduces the formation and branching of primitive blood vessels in embryoid body culture systems. Mechanistically, NgBR knockdown not only decreases both Nogo-B and VEGF-stimulated endothelial cell migration by abolishing Akt phosphorylation, but also decreases the expression of CCM1 and CCM2 proteins. Furthermore, we performed immunofluorescence (IF) staining of NgBR in human cerebral cavernous malformation patient tissue sections. The quantitative analysis results showed that NgBR expression levels in CD31 positive endothelial cells is significantly decreased in patient tissue sections. These results suggest that NgBR may be one of important genes coordinating the cerebral vasculature development. PMID:26746789

  11. Effect of everolimus on pre-existing atherosclerosis in LDL-receptor deficient mice.

    PubMed

    Beutner, Frank; Brendel, Désiré; Teupser, Daniel; Sass, Kristina; Baber, Ronny; Mueller, Marc; Ceglarek, Uta; Thiery, Joachim

    2012-06-01

    Proliferation signal inhibitors/mTOR-inhibitors have been shown to reduce de novo development of hypercholesterolemic atherosclerosis in animal models. However, their effect on pre-existing atherosclerosis has not yet been studied. Feeding LDL-R-KO mice a high cholesterol diet for 12 weeks resulted in formation of moderate fibroatheroma (induction phase). Sixty mice received either everolimus (1 or 5 mg/kg) or no everolimus for further 12 weeks (treatment phase). Everolimus significantly enhanced hypercholesterolemia (plasma cholesterol +45%, p<0.001). Atherosclerosis progressed obstructively in treated and non-treated mice. Everolimus (5 mg/kg) tended to reduced progression in aortic root lesions (0.28±0.02 vs. 0.33±0.03 mm(2), p=ns) and brachiocephalic lesions (0.044±0.006 vs. 0.066±0.012 mm(2), p=ns) but without significance. Everolimus (5mg/kg) resulted in an arrest of CD68 positive plaque area (p=0.03) and nearly halved CD68 fraction (p=0.05) in aortic root lesions but not in brachiocephalic lesions. Taken together, despite a trend to reduced progression and inflammatory cell content there was less conclusive net effect of everolimus treatment than expected. A higher potential of everolimus in the treatment of atherosclerosis might be obscured by its concomitant hypercholesterolemia. Considering stronger effects in previous studies we suggest that everolimus might exert more potent anti-atherogenic properties in earlier stages of atherogenesis than in advanced atherosclerosis. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  12. State-dependent alterations in hippocampal oscillations in serotonin 1A receptor-deficient mice.

    PubMed

    Gordon, Joshua A; Lacefield, Clay O; Kentros, Clifford G; Hen, Rene

    2005-07-13

    Mice lacking the serotonin 1A receptor (5-HT(1A)R) show increased levels of anxiety-related behavior across multiple tests and background strains. Tissue-specific rescue experiments, lesion studies, and neurophysiological findings all point toward the hippocampus as a potential mediator of the phenotype. Serotonin, acting through 5-HT(1A)Rs, can suppress hippocampal theta-frequency oscillations, suggesting that theta oscillations might be increased in the knock-outs. To test this hypothesis, local field potential recordings were obtained from the hippocampus of awake, behaving knock-outs and wild-type littermates. The magnitude of theta oscillations was increased in the knock-outs, specifically in the anxiety-provoking elevated plus maze and not in a familiar environment or during rapid eye movement sleep. Theta power correlated with the fraction of time spent in the open arms, an anxiety-related behavioral variable. These results suggest a possible role for the hippocampus, and theta oscillations in particular, in the expression of anxiety in 5-HT(1A)R-deficient mice.

  13. Nogo-B receptor deficiency causes cerebral vasculature defects during embryonic development in mice.

    PubMed

    Rana, Ujala; Liu, Zhong; Kumar, Suresh N; Zhao, Baofeng; Hu, Wenquan; Bordas, Michelle; Cossette, Stephanie; Szabo, Sara; Foeckler, Jamie; Weiler, Hartmut; Chrzanowska-Wodnicka, Magdalena; Holtz, Mary L; Misra, Ravindra P; Salato, Valerie; North, Paula E; Ramchandran, Ramani; Miao, Qing Robert

    2016-02-15

    Nogo-B receptor (NgBR) was identified as a receptor specific for Nogo-B. Our previous work has shown that Nogo-B and its receptor (NgBR) are essential for chemotaxis and morphogenesis of endothelial cells in vitro and intersomitic vessel formation via Akt pathway in zebrafish. Here, we further demonstrated the roles of NgBR in regulating vasculature development in mouse embryo and primitive blood vessel formation in embryoid body culture systems, respectively. Our results showed that NgBR homozygous knockout mice are embryonically lethal at E7.5 or earlier, and Tie2Cre-mediated endothelial cell-specific NgBR knockout (NgBR ecKO) mice die at E11.5 and have severe blood vessel assembly defects in embryo. In addition, mutant embryos exhibit dilation of cerebral blood vessel, resulting in thin-walled endothelial caverns. The similar vascular defects also were detected in Cdh5(PAC)-CreERT2 NgBR inducible ecKO mice. Murine NgBR gene-targeting embryonic stem cells (ESC) were generated by homologous recombination approaches. Homozygous knockout of NgBR in ESC results in cell apoptosis. Heterozygous knockout of NgBR does not affect ESC cell survival, but reduces the formation and branching of primitive blood vessels in embryoid body culture systems. Mechanistically, NgBR knockdown not only decreases both Nogo-B and VEGF-stimulated endothelial cell migration by abolishing Akt phosphorylation, but also decreases the expression of CCM1 and CCM2 proteins. Furthermore, we performed immunofluorescence (IF) staining of NgBR in human cerebral cavernous malformation patient tissue sections. The quantitative analysis results showed that NgBR expression levels in CD31 positive endothelial cells is significantly decreased in patient tissue sections. These results suggest that NgBR may be one of important genes coordinating the cerebral vasculature development. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Validation of dopamine receptor DRD1 and DRD2 antibodies using receptor deficient mice.

    PubMed

    Stojanovic, Tamara; Orlova, Michaela; Sialana, Fernando J; Höger, Harald; Stuchlik, Stanislav; Milenkovic, Ivan; Aradska, Jana; Lubec, Gert

    2017-06-01

    Dopamine receptors 1 and 2 (DRD1, DRD2) are essential for signaling in the brain for a multitude of brain functions. Previous work using several antibodies against these receptors is abundant but only the minority of antibodies used have been validated and, therefore, the results of these studies remain uncertain. Herein, antibodies against DRD1 (Merck Millipore AB1765P, Santa Cruz Biotechnology sc-14001, Sigma Aldrich D2944, Alomone Labs ADR-001) and DRD2 (Abcam ab21218, Merck Millipore AB5084P, Santa Cruz Biotechnology sc-5303) have been tested using western blotting and immunohistochemistry on mouse striatum (wild type and corresponding knock-out mice) and when specific, they were further evaluated on rat and human striatum. Moreover, a DRD1 antibody and a DRD2 antibody that were found specific in our tests were used for immunoprecipitation with subsequent mass spectrometrical identification of the immunoprecipitate. Two out of nine antibodies (anti DRD1 Sigma Aldrich D2944 and anti DRD2 Merck Millipore AB5084P) against the abovementioned dopamine receptors were specific for DRD1 and DRD2 as evaluated by western blotting and immunohistochemistry and the immunoprecipitate indeed contained DRD1 and DRD2 as revealed by mass spectrometry. The observed findings may question the use of so far non-validated antibodies against the abovementioned dopamine receptors. Own observations may be valuable for the interpretation of previous results and the design of future studies using dopamine receptors DRD1 or DRD2.

  15. Salusin-α attenuates hepatic steatosis and atherosclerosis in high fat diet-fed low density lipoprotein receptor deficient mice.

    PubMed

    Tang, Kun; Wang, Fei; Zeng, Yi; Chen, XueMeng; Xu, XiaoLe

    2018-04-26

    Salusin-α is an endogenous bioactive peptide and likely to prevent atherosclerosis. But its protective effect against atherosclerosis in vivo remains poorly understood. The aim of the present study was to determine the potential effects of salusin-α on atherosclerosis and its associated metabolic disorders in high fat diet (HFD)-fed low density lipoprotein receptor deficient (LDLr -/- ) mice, and also explore the possible underlying mechanisms involved. Our data showed that after 12 weeks treatment, salusin-α ameliorated HFD-induced weight gain, hyperlipidemia, and serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Salusin-α suppressed HFD-induced hepatic steatosis and regulated gene expression of fatty acid synthase, acetyl coenzyme A carboxylase-α, peroxisome proliferator-activated receptor-α, camitine palmitoyltransferase-1α and CYP7A1 in liver. Salusin-α reduced atherosclerotic plaque area and macrophage foam cell formation. Salusin-α prevented hepatic and aortic inflammation as evidenced by the reduced macrophage recruitment and mRNA expression of IL-6 and TNF-α in both liver and aorta. Salusin-α also reduced hepatic and aortic oxidative stress by normalizing activities of antioxidant enzymes in liver and suppressing reactive oxygen species generation and protein expressions of NADPH-oxidase (NOX) 2 and NOX4 in both liver and aorta. Our present data suggest that salusin-α could reduce hepatic steatosis and atherosclerosis via its pleiotropic effects, including amelioration of lipid profiles, regulation of some key molecules involved in lipid metabolism in liver, anti-oxidative effect and anti-inflammatory action. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. CD8+ T Cell Response to Gammaherpesvirus Infection Mediates Inflammation and Fibrosis in Interferon Gamma Receptor-Deficient Mice

    PubMed Central

    O’Flaherty, Brigid M.; Matar, Caline G.; Wakeman, Brian S.; Garcia, AnaPatricia; Wilke, Carol A.; Courtney, Cynthia L.; Moore, Bethany B.; Speck, Samuel H.

    2015-01-01

    Idiopathic pulmonary fibrosis (IPF), one of the most severe interstitial lung diseases, is a progressive fibrotic disorder of unknown etiology. However, there is growing appreciation for the role of viral infection in disease induction and/or progression. A small animal model of multi-organ fibrosis, which involves murine gammaherpesvirus (MHV68) infection of interferon gamma receptor deficient (IFNγR-/-) mice, has been utilized to model the association of gammaherpesvirus infections and lung fibrosis. Notably, several MHV68 mutants which fail to induce fibrosis have been identified. Our current study aimed to better define the role of the unique MHV68 gene, M1, in development of pulmonary fibrosis. We have previously shown that the M1 gene encodes a secreted protein which possesses superantigen-like function to drive the expansion and activation of Vβ4+ CD8+ T cells. Here we show that M1-dependent fibrosis is correlated with heightened levels of inflammation in the lung. We observe an M1-dependent cellular infiltrate of innate immune cells with most striking differences at 28 days-post infection. Furthermore, in the absence of M1 protein expression we observed reduced CD8+ T cells and MHV68 epitope specific CD8+ T cells to the lungs—despite equivalent levels of viral replication between M1 null and wild type MHV68. Notably, backcrossing the IFNγR-/- onto the Balb/c background, which has previously been shown to exhibit weak MHV68-driven Vβ4+ CD8+ T cell expansion, eliminated MHV68-induced fibrosis—further implicating the activated Vβ4+ CD8+ T cell population in the induction of fibrosis. We further addressed the role that CD8+ T cells play in the induction of fibrosis by depleting CD8+ T cells, which protected the mice from fibrotic disease. Taken together these findings are consistent with the hypothesized role of Vβ4+ CD8+ T cells as mediators of fibrotic disease in IFNγR-/- mice. PMID:26317335

  17. Mechanical Vibration Mitigates the Decrease of Bone Quantity and Bone Quality of Leptin Receptor-Deficient Db/Db Mice by Promoting Bone Formation and Inhibiting Bone Resorption.

    PubMed

    Jing, Da; Luo, Erping; Cai, Jing; Tong, Shichao; Zhai, Mingming; Shen, Guanghao; Wang, Xin; Luo, Zhuojing

    2016-09-01

    Leptin, a major hormonal product of adipocytes, is involved in regulating appetite and energy metabolism. Substantial studies have revealed the anabolic actions of leptin on skeletons and bone cells both in vivo and in vitro. Growing evidence has substantiated that leptin receptor-deficient db/db mice exhibit decreased bone mass and impaired bone microstructure despite several conflicting results previously reported. We herein systematically investigated bone microarchitecture, mechanical strength, bone turnover and its potential molecular mechanisms in db/db mice. More importantly, we also explored an effective approach for increasing bone mass in leptin receptor-deficient animals in an easy and noninvasive manner. Our results show that deterioration of trabecular and cortical bone microarchitecture and decreases of skeletal mechanical strength-including maximum load, yield load, stiffness, energy, tissue-level modulus and hardness-in db/db mice were significantly ameliorated by 12-week, whole-body vibration (WBV) with 0.5 g, 45 Hz via micro-computed tomography (μCT), three-point bending, and nanoindentation examinations. Serum biochemical analysis shows that WBV significantly decreased serum tartrate-resistant acid phosphatase 5b (TRACP5b) and CTx-1 levels and also mitigated the reduction of serum osteocalcin (OCN) in db/db mice. Bone histomorphometric analysis confirmed that decreased bone formation-lower mineral apposition rate, bone formation rate, and osteoblast numbers in cancellous bone-in db/db mice were suppressed by WBV. Real-time PCR assays show that WBV mitigated the reductions of tibial alkaline phosphatase (ALP), OCN, Runt-related transcription factor 2 (RUNX2), type I collagen (COL1), BMP2, Wnt3a, Lrp6, and β-catenin mRNA expression, and prevented the increases of tibial sclerostin (SOST), RANK, RANKL, RANL/osteoprotegerin (OPG) gene levels in db/db mice. Our results show that WBV promoted bone quantity and quality in db/db mice with obvious

  18. Antisense oligonucleotide reduction of apoB-ameliorated atherosclerosis in LDL receptor-deficient mice[S

    PubMed Central

    Mullick, Adam E.; Fu, Wuxia; Graham, Mark J.; Lee, Richard G.; Witchell, Donna; Bell, Thomas A.; Whipple, Charles P.; Crooke, Rosanne M.

    2011-01-01

    Chronic elevations of plasma apolipoprotein B (apoB) are strongly associated with cardiovascular disease. We have previously demonstrated that inhibition of hepatic apoB mRNA using antisense oligonucleotides (ASO) results in reductions of apoB, VLDL, and LDL in several preclinical animal models and humans. In this study, we evaluated the anti-atherogenic effects of a murine-specific apoB ASO (ISIS 147764) in hypercholesterolemic LDLr deficient (LDLr−/−) mice. ISIS 147764 was administered weekly at 25-100 mg/kg for 10-12 weeks and produced dose-dependent reductions of hepatic apoB mRNA and plasma LDL by 60-90%. No effects on these parameters were seen in mice receiving control ASOs. ApoB ASO treatment also produced dose-dependent reductions of aortic en face and sinus atherosclerosis from 50-90%, with high-dose treatment displaying less disease than the saline-treated, chow-fed LDLr−/− mice. No changes in intestinal cholesterol absorption were seen with apoB ASO treatment, suggesting that the cholesterol-lowering pharmacology of 147764 was primarily due to inhibition of hepatic apoB synthesis and secretion. In summary, ASO-mediated suppression of apoB mRNA expression profoundly reduced plasma lipids and atherogenesis in LDLr−/− mice, leading to the hypothesis that apoB inhibition in humans with impaired LDLr activity may produce similar effects. PMID:21343632

  19. Toll-like Receptor 4 Deficiency Decreases Atherosclerosis but Does Not Protect against Inflammation in Obese LDL Receptor-Deficient Mice

    PubMed Central

    Ding, Yilei; Subramanian, Savitha; Montes, Vince N.; Goodspeed, Leela; Wang, Shari; Han, Chang Yeop; Teresa, Antonio Sta.; Kim, Jinkyu; O’Brien, Kevin D.; Chait, Alan

    2013-01-01

    Objective Obesity is associated with insulin resistance, chronic low-grade inflammation and atherosclerosis. Toll-like receptor 4 (TLR4) participates in the cross-talk between inflammation and insulin resistance, being activated by both lipopolysaccharide and saturated fatty acids. This study was undertaken to determine whether TLR4 deficiency has a protective role in inflammation, insulin resistance and atherosclerosis induced by a diabetogenic diet. Methods and Results TLR4 and LDL receptor double knockout (Tlr4−/−Ldlr−/−) mice and Ldlr−/− mice were fed either a normal chow or a diabetogenic diet for 24 weeks. Tlr4−/−Ldlr−/− mice fed a diabetogenic diet showed improved plasma cholesterol and triglyceride levels but developed obesity, hyperinsulinemia and glucose intolerance equivalent to obese Ldlr−/− mice. Adipocyte hypertrophy, macrophage accumulation and local inflammation were not attenuated in intra-abdominal adipose tissue in Tlr4−/−Ldlr−/− mice. However, TLR4 deficiency led to markedly decreased atherosclerosis in obese Tlr4−/−Ldlr−/− mice. Compensatory up-regulation of TLR2 expression was observed both in obese TLR4 deficient mice and in palmitate-treated TLR4-silenced 3T3-L1 adipocytes. Conclusions TLR4 deficiency decreases atherosclerosis without affecting obesity-induced inflammation and insulin resistance in LDL receptor deficient mice. Alternative pathways may be responsible for adipose tissue macrophage infiltration and insulin resistance that occurs in obesity. PMID:22580897

  20. Fas receptor-deficient lpr mice are protected against acetaminophen hepatotoxicity due to higher glutathione synthesis and enhanced detoxification of oxidant stress.

    PubMed

    Williams, C David; McGill, Mitchell R; Farhood, Anwar; Jaeschke, Hartmut

    2013-08-01

    Acetaminophen (APAP) overdose is a classical model of hepatocellular necrosis; however, the involvement of the Fas receptor in the pathophysiology remains controversial. Fas receptor-deficient (lpr) and C57BL/6 mice were treated with APAP to compare the mechanisms of hepatotoxicity. Lpr mice were partially protected against APAP hepatotoxicity as indicated by reduced plasma ALT and GDH levels and liver necrosis. Hepatic Cyp2e1 protein, adduct formation and hepatic glutathione (GSH) depletion were similar, demonstrating equivalent reactive metabolite generation. There was no difference in cytokine formation or hepatic neutrophil recruitment. Interestingly, hepatic GSH recovered faster in lpr mice than in wild type animals resulting in enhanced detoxification of reactive oxygen species. Driving the increased GSH levels, mRNA induction and protein expression of glutamate-cysteine ligase (gclc) were higher in lpr mice. Inducible nitric oxide synthase (iNOS) mRNA and protein levels at 6h were significantly lower in lpr mice, which correlated with reduced nitrotyrosine staining. Heat shock protein 70 (Hsp70) mRNA levels were substantially higher in lpr mice after APAP. Our data suggest that the faster recovery of hepatic GSH levels during oxidant stress and peroxynitrite formation, reduced iNOS expression and enhanced induction of Hsp70 attenuated the susceptibility to APAP-induced cell death in lpr mice. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. SKI-II--a sphingosine kinase 1 inhibitor--exacerbates atherosclerosis in low-density lipoprotein receptor-deficient (LDL-R-/-) mice on high cholesterol diet.

    PubMed

    Potì, Francesco; Ceglarek, Uta; Burkhardt, Ralph; Simoni, Manuela; Nofer, Jerzy-Roch

    2015-05-01

    Sphingosine 1-phosphate (S1P) is a lysosphingolipid associated with high-density lipoproteins (HDL) that contributes to their anti-atherogenic potential. We investigated whether a reduction in S1P plasma levels affects atherosclerosis in low-density lipoprotein receptor deficient (LDL-R-/-) mice. LDL-R-/- mice on Western diet containing low (0.25% w/w) or high (1.25% w/w) cholesterol were treated for 16 weeks with SKI-II, a sphingosine kinase 1 inhibitor that significantly reduced plasma S1P levels. SKI-II treatment increased atherosclerotic lesions in the thoracic aorta in mice on high but not low cholesterol diet. This compound did not affect body weight, blood cell counts and plasma total and HDL cholesterol, but decreased triglycerides. In addition, mice on high cholesterol diet receiving SKI-II showed elevated levels of tumor necrosis factor-α and endothelial adhesion molecules (sICAM-1, sVCAM-1). Prolonged lowering of plasma S1P produces pro-atherogenic effects in LDL-R-/- mice that are evident under condition of pronounced hypercholesterolemia. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Indoleamine 2 3-dioxygenase knockout limits angiotensin II-induced aneurysm in low density lipoprotein receptor-deficient mice fed with high fat diet.

    PubMed

    Metghalchi, Sarvenaz; Vandestienne, Marie; Haddad, Yacine; Esposito, Bruno; Dairou, Julien; Tedgui, Alain; Mallat, Ziad; Potteaux, Stephane; Taleb, Soraya

    2018-01-01

    Abdominal aortic aneurysm (AAA) is an age-associated disease characterized by chronic inflammation, vascular cell apoptosis and metalloproteinase-mediated extracellular matrix degradation. Despite considerable progress in identifying targets involved in these processes, therapeutic approaches aiming to reduce aneurysm growth and rupture are still scarce. Indoleamine 2-3 dioxygenase 1 (IDO) is the first and rate-limiting enzyme involved in the conversion of tryptophan (Trp) into kynurenine (Kyn) pathway. In this study, we investigated the role of IDO in two different models of AAA in mice. Mice with deficiencies in both low density receptor-deficient (Ldlr-/-) and IDO (Ldlr-/-Ido1-/-) were generated by cross-breeding Ido1-/- mice with Ldlr-/-mice. To induce aneurysm, these mice were infused with angiotensin II (Ang II) (1000 ng/min/kg) and fed with high fat diet (HFD) during 28 days. AAAs were present in almost all Ldlr-/- infused with AngII, but only in 50% of Ldlr-/-Ido1-/- mice. Immunohistochemistry at an early time point (day 7) revealed no changes in macrophage and T lymphocyte infiltration within the vessel wall, but showed reduced apoptosis, as assessed by TUNEL assay, and increased α-actin staining within the media of Ldlr-/-Ido1-/- mice, suggesting enhanced survival of vascular smooth muscle cells (VSMCs) in the absence of IDO. In another model of elastase-induced AAA in C57Bl/6 mice, IDO deficiency had no effect on aneurysm formation. Our study showed that the knockout of IDO prevented VSMC apoptosis in AngII -treated Ldlr-/- mice fed with HFD, suggesting a detrimental role of IDO in AAA formation and thus would be an important target for the treatment of aneurysm.

  3. Thiol Oxidative Stress Induced by Metabolic Disorders Amplifies Macrophage Chemotactic Responses and Accelerates Atherogenesis and Kidney Injury in LDL Receptor-Deficient Mice

    PubMed Central

    Qiao, Mu; Zhao, Qingwei; Lee, Chi Fung; Tannock, Lisa R.; Smart, Eric J.; LeBaron, Richard G.; Phelix, Clyde F.; Rangel, Yolanda; Asmis, Reto

    2009-01-01

    Background Strengthening the macrophage glutathione redox buffer reduces macrophage content and decreases the severity of atherosclerotic lesions in LDL receptor-deficient (LDLR−/−) mice, but the underlying mechanisms were not clear. This study examined the effect of metabolic stress on the thiol redox state, chemotactic activity in vivo and the recruitment of macrophages into atherosclerotic lesions and kidneys of LDL-R−/− mice in response to mild, moderate and severe metabolic stress. Methods and Results Reduced glutathione (GSH) and glutathione disulfide (GSSG) levels in peritoneal macrophages isolated from mildly, moderately and severe metabolically-stressed LDL-R−/− mice were measured by HPLC, and the glutathione reduction potential (Eh) was calculated. Macrophage Eh correlated with the macrophage content in both atherosclerotic (r2=0.346, P=0.004) and renal lesions (r2=0.480, P=0.001) in these mice as well as the extent of both atherosclerosis (r2=0.414, P=0.001) and kidney injury (r2=0.480, P=0.001). Compared to LDL-R−/− mice exposed to mild metabolic stress, macrophage recruitment into MCP-1-loaded Matrigel plugs injected into LDL-R−/− mice increased 2.6–fold in moderately metabolically-stressed mice and 9.8–fold in severely metabolically-stressed mice. The macrophage Eh was a strong predictor of macrophage chemotaxis (r2=0.554, P<0.001). Conclusion Thiol oxidative stress enhances macrophage recruitment into vascular and renal lesions by increasing the responsiveness of macrophages to chemoattractants. This novel mechanism contributes at least in part to accelerated atherosclerosis and kidney injury associated with dyslipidemia and diabetes in mice. PMID:19592463

  4. Effect of macrophage overexpression of murine liver X receptor-alpha (LXR-alpha) on atherosclerosis in LDL-receptor deficient mice.

    PubMed

    Teupser, Daniel; Kretzschmar, Daniel; Tennert, Carsten; Burkhardt, Ralph; Wilfert, Wolfgang; Fengler, Dörte; Naumann, Ronald; Sippel, Albrecht E; Thiery, Joachim

    2008-11-01

    Background- The nuclear liver X receptor-alpha (LXR-alpha) has been implicated in the regulation of intracellular cholesterol homeostasis, inflammatory response, and atherosclerosis susceptibility. The aim of the present study was to test whether transgenic expression of LXR-alpha might affect these mechanisms and result in a reduction of atherosclerosis. We generated mice with macrophage overexpression of mouse LXR-alpha, evidenced by significantly elevated expression levels of LXR-target genes (ABCA1, ABCG1) in these cells. For atherosclerosis studies, mice were crossed onto the LDL-receptor deficient background. Plasma lipids and lipoproteins as well as liver triglycerides were not significantly different between transgenic animals and nontransgenic controls. However, lesion area at the brachiocephalic artery (BCA) was significantly reduced (-83%, P=0.02) in male LXR-alpha transgenic mice. This was associated with a significantly increased cholesterol efflux to acceptor-free media (+24%, P=0.002) and ApoA1 containing media (+20%, P<0.0001) as well as reduced lipopolysaccharide (LPS)-induced NO-release from macrophages of transgenic animals, providing a potential mechanism for the reduction of atherosclerosis. Our data show for the first time that transgenic overexpression of LXR-alpha in macrophages has significant antiatherogenic properties. We conclude that overexpression of LXR-alpha in macrophages might be useful as a therapeutic principle for the prevention of atherosclerosis.

  5. Lack of ghrelin secretion in response to fasting in cholecystokinin-A (-1), -B (-2) receptor-deficient mice.

    PubMed

    Sakurai, Chihiro; Ohta, Minoru; Kanai, Setsuko; Uematsu, Hiroshi; Funakoshi, Akihiro; Miyasaka, Kyoko

    2006-12-01

    Cholecystokinin receptors (CCK-Rs) have been classified into two subtypes: CCK-AR (1R) and -BR (2R). We generated CCK-AR(-/-), CCK-BR(-/-), and CCK-AR(-/-)BR(-/-) mice and found that the gastric emptying of a liquid meal was increased in CCK-BR(-/-) and AR(-/-)BR(-/-) mice, compared with wild-type and CCK-AR(-/-) mice. Given that enhanced gastric emptying leads to eating, food intake after overnight fasting was examined, as was the effect of CCK-8S on food intake. Male mice 6-8 months of age were deprived of food for 16 h with free access to water, after which they were injected intraperitoneally (0.1 ml/mouse) with either vehicle or CCK-8 (0.3, 1.0, or 3.0 nmol/mouse), and their food intake was monitored for 4 h. CCK-8S inhibited food intake in wild-type and CCK-BR(-/-) mice, but not in CCK-AR(-/-) or AR(-/-)BR(-/-) mice. Unexpectedly, we observed a lower food intake in CCK-AR(-/-)BR (-/-) mice treated with vehicle than in mice of the other genotypes. To examine the mechanism of decrease in food intake in CCK-AR(-/-)BR(-/-) mice, the involvement of ghrelin was determined in wild-type and CCK-AR(-/-)BR(-/-) mice. Fasting plasma ghrelin levels were significantly lower in CCK-AR (-/-)BR(-/-) mice than in wild-type mice, and no increase in response to fasting was observed in CCK-AR(-/-)BR(-/-) mice. An administration of acyl-ghrelin produced a small increase in food intake in CCK-AR(-/-)BR(-/-) mice, but not to the levels of wild-type mice. In conclusion, CCK-AR(-/-)BR(-/-) mice showed lower food intake as well as lower response to exogenous ghrelin, and a lower plasma ghrelin level after fasting, though which receptor is more important is unknown.

  6. The High Calcium, High Phosphorus Rescue Diet Is Not Suitable to Prevent Secondary Hyperparathyroidism in Vitamin D Receptor Deficient Mice

    PubMed Central

    Grundmann, Sarah M.; Brandsch, Corinna; Rottstädt, Daniela; Kühne, Hagen; Stangl, Gabriele I.

    2017-01-01

    The vitamin D receptor (VDR) knockout (KO) mouse is a common model to unravel novel metabolic functions of vitamin D. It is recommended to feed these mice a high calcium (2%), high phosphorus (1.25%) diet, termed rescue diet (RD) to prevent hypocalcaemia and secondary hyperparathyroidism. First, we characterized the individual response of VDR KO mice to feeding a RD and found that the RD was not capable of normalizing the parathyroid hormone (PTH) concentrations in each VDR KO mouse. In a second study, we aimed to study whether RD with additional 1 and 2% calcium (in total 3 and 4% of the diet) is able to prevent secondary hyperparathyroidism in the VDR KO mice. Wild type (WT) mice and VDR KO mice that received a normal calcium and phosphorus diet (ND) served as controls. Data demonstrated that the RD was no more efficient than the ND in normalizing PTH levels. An excessive dietary calcium concentration of 4% was required to reduce serum PTH concentrations in the VDR KO mice to PTH levels measured in WT mice. This diet, however, resulted in higher concentrations of circulating intact fibroblast growth factor 23 (iFGF23). To conclude, the commonly used RD is not suitable to normalize the serum PTH in VDR KO mice. Extremely high dietary calcium concentrations are necessary to prevent secondary hyperthyroidism in these mice, with the consequence that iFGF23 concentrations are being raised. Considering that PTH and iFGF23 exert numerous VDR independent effects, data obtained from VDR KO mice cannot be attributed solely to vitamin D. PMID:28443031

  7. Androgen receptor deficiency in monocytes/macrophages does not alter adiposity or glucose homeostasis in male mice.

    PubMed

    Rubinow, Katya B; Houston, Barbara; Wang, Shari; Goodspeed, Leela; Ogimoto, Kayoko; Morton, Gregory J; McCarty, Christopher; Braun, Robert E; Page, Stephanie T

    2018-01-01

    Androgen deprivation in men leads to increased adiposity, but the mechanisms underlying androgen regulation of fat mass have not been fully defined. Androgen receptor (AR) is expressed in monocytes/macrophages, which are resident in key metabolic tissues and influence energy metabolism in surrounding cells. Male mice bearing a cell-specific knockout of the AR in monocytes/macrophages (M-ARKO) were generated to determine whether selective loss of androgen signaling in these cells would lead to altered body composition. Wild-type (WT) and M-ARKO mice (12-22 weeks of age, n = 12 per group) were maintained on a regular chow diet for 8 weeks and then switched to a high-fat diet for 8 additional weeks. At baseline and on both the regular chow and high-fat diets, no differences in lean mass or fat mass were observed between groups. Consistent with the absence of differential body weight or adiposity, no differences in food intake (3.0 ± 0.5 g per day for WT mice vs 2.8 ± 0.4 g per day for M-ARKO mice) or total energy expenditure (0.6 ± 0.1 Kcal h -1 for WT mice vs 0.5 ± 0.1 Kcal h -1 for M-ARKO mice) were evident between groups during high-fat feeding. Liver weight was greater in M-ARKO than that in WT mice (1.5 ± 0.1 g vs 1.3 ± 0.0 g, respectively, P = 0.02). Finally, M-ARKO mice did not exhibit impairments in glucose tolerance or insulin sensitivity relative to WT mice at any study time point. In aggregate, these findings suggest that AR signaling specifically in monocytes/macrophages does not contribute to the regulation of systemic energy balance, adiposity, or insulin sensitivity in male mice.

  8. CER-001, a HDL-mimetic, stimulates the reverse lipid transport and atherosclerosis regression in high cholesterol diet-fed LDL-receptor deficient mice.

    PubMed

    Tardy, Claudine; Goffinet, Marine; Boubekeur, Nadia; Ackermann, Rose; Sy, Gavin; Bluteau, Alice; Cholez, Guy; Keyserling, Constance; Lalwani, Narendra; Paolini, John F; Dasseux, Jean-Louis; Barbaras, Ronald; Baron, Rudi

    2014-01-01

    CER-001 is a novel engineered HDL-mimetic comprised of recombinant human apoA-I and phospholipids that was designed to mimic the beneficial properties of nascent pre-β HDL. In this study, we have evaluated the capacity of CER-001 to perform reverse lipid transport in single dose studies as well as to regress atherosclerosis in LDLr(-/-) mice after short-term multiple-dose infusions. CER-001 induced cholesterol efflux from macrophages and exhibited anti-inflammatory response similar to natural HDL. Studies with HUVEC demonstrated CER-001 at a concentration of 500 μg/mL completely suppressed the secretion of cytokines IL-6, IL-8, GM-CSF and MCP-1. Following infusion of CER-001 (10mg/kg) in C57Bl/6J mice, we observed a transient increase in the mobilization of unesterified cholesterol in HDL particles containing recombinant human apoA-I. Finally we show that cholesterol elimination was stimulated in CER-001 treated animals as demonstrated by the increased cholesterol concentration in liver and feces. In a familial hypercholesterolemia mouse model (LDL-receptor deficient mice), the infusion of CER-001 caused 17% and 32% reductions in plaque size, 17% and 23% reductions in lipid content after 5 and 10 doses given every 2 days, respectively. Also, there was an 80% reduction in macrophage content in the plaque following 5 doses, and decreased VCAM-1 expression by 16% and 22% in the plaque following 5 and 10 intravenous doses of CER-001, respectively. These data demonstrate that CER-001 rapidly enhances reverse lipid transport in the mouse, reducing vascular inflammation and promoting regression of diet-induced atherosclerosis in LDLr(-/-) mice upon a short-term multiple dose treatment. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. Bile acids override steatosis in farnesoid X receptor deficient mice in a model of non-alcoholic steatohepatitis

    SciTech Connect

    Wu, Weibin; Liu, Xijun; Peng, Xiaomin

    2014-05-23

    Highlights: • FXR deficiency enhanced MCD diet-induced hepatic fibrosis. • FXR deficiency attenuated MCD diet-induced hepatic steatosis. • FXR deficiency repressed genes involved in fatty acid uptake and triglyceride accumulation. - Abstract: Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases, and the pathogenesis is still not well known. The farnesoid X receptor (FXR) is a member of the nuclear hormone receptor superfamily and plays an essential role in maintaining bile acid and lipid homeostasis. In this study, we study the role of FXR in the pathogenesis of NFALD. We found that FXR deficient (FXR{sup −/−})more » mice fed methionine- and choline-deficient (MCD) diet had higher serum ALT and AST activities and lower hepatic triglyceride levels than wild-type (WT) mice fed MCD diet. Expression of genes involved in inflammation (VCAM-1) and fibrosis (α-SMA) was increased in FXR{sup −/−} mice fed MCD diet (FXR{sup −/−}/MCD) compared to WT mice fed MCD diet (WT/MCD). Although MCD diet significantly induced hepatic fibrosis in terms of liver histology, FXR{sup −/−}/MCD mice showed less degree of hepatic steatosis than WT/MCD mice. Moreover, FXR deficiency synergistically potentiated the elevation effects of MCD diet on serum and hepatic bile acids levels. The super-physiological concentrations of hepatic bile acids in FXR{sup −/−}/MCD mice inhibited the expression of genes involved in fatty acid uptake and triglyceride accumulation, which may be an explanation for less steatosis in FXR{sup −/−}/MCD mice in contrast to WT/MCD mice. These results suggest that hepatic bile acids accumulation could override simple steatosis in hepatic injury during the progression of NAFLD and further emphasize the role of FXR in maintaining hepatic bile acid homeostasis in liver disorders and in hepatic protection.« less

  10. Calpain Inhibition Attenuates Angiotensin II-induced Abdominal Aortic Aneurysms and Atherosclerosis in LDL Receptor Deficient Mice

    PubMed Central

    Subramanian, Venkateswaran; Uchida, Haruhito Adam; Ijaz, Talha; Moorleghen, Jessica J.; Howatt, Deborah A.; Balakrishnan, Anju

    2011-01-01

    Chronic infusion of angiotensin II (AngII) augments atherosclerosis and abdominal aortic aneurysm (AAAs) formation in hypercholesterolemic mice. AngII-induced AAAs are associated with medial macrophage accumulation and matrix metalloproteinase (MMP) activation. Inhibition of calpain, a calcium-activated neutral cysteine protease, by overexpression of its endogenous inhibitor, calpastatin, attenuates AngII-induced leukocyte infiltration, perivascular inflammation, and MMP activation in mice. The purpose of this study was to define whether pharmacological inhibition of calpain influences AngII-induced AAAs in hypercholesterolemic mice. Male LDL receptor −/− mice were fed a fat-enriched diet and administered with either vehicle or a calpain-specific inhibitor, BDA-410 (30 mg/kg/day) for 5 weeks. After 1 week of feeding, mice were infused with AngII (1,000 ng/kg/min) for 4 weeks. AngII-infusion profoundly increased aortic calpain protein and activity. BDA-410 administration had no effect on plasma cholesterol concentrations or AngII-increased systolic blood pressure. Calpain inhibition significantly attenuated AngII-induced AAA formation and atherosclerosis development. BDA-410 administration attenuated activation of MMP12, pro-inflammatory cytokines (IL-6, MCP-1) and macrophage infiltration into the aorta. BDA-410 administration significantly attenuated thioglycollate-elicited macrophage accumulation in the peritoneal cavity. We conclude that calpain inhibition using BDA-410 attenuated AngII-induced AAA formation and atherosclerosis development in LDL receptor −/− mice. PMID:21964156

  11. Passive Immunization with Hypochlorite-oxLDL Specific Antibodies Reduces Plaque Volume in LDL Receptor-Deficient Mice

    PubMed Central

    van Leeuwen, Marcella; Kemna, Michael J.; de Winther, Menno P. J.; Boon, Louis; Duijvestijn, Adriaan M.; Henatsch, Darius; Bos, Nico A.; Gijbels, Marion J. J.; Tervaert, Jan Willem Cohen

    2013-01-01

    Aims New strategies to overcome complications of cardiovascular diseases are needed. Since it has been demonstrated that atherosclerosis is an inflammatory disease, modulation of the immune system may be a promising approach. Previously, it was suggested that antibodies may confer protective effects on the development of atherosclerosis. In this study, we hypothesised that passive immunization with anti-oxLDL IgM antibodies specific for hypochlorite (HOCl) may be athero-protective in mice. Methods and Results Monoclonal mouse IgM antibodies were produced and the antibody with specificity for hypochlorite-oxLDL (HOCl-oxLDL) (Moab A7S8) was selected. VH sequence determination revealed that Moab A7S8 is a natural IgM antibody. Atherosclerosis in LDLr−/− mice was induced by a perivascular collar placement around the right carotid artery in combination with feeding a high-fat diet. Subsequently, the mice were treated every six days with 500 µg Moab A7S8, non-relevant IgM or with PBS and the carotid arteries and aortic roots were studied for atherosclerosis. Passive immunization with this Moab A7S8 resulted in a significant reduced plaque volume formation in LDLr−/− mice when compared with PBS treatment (P = 0.002 and P = 0.035). Cholesterol levels decreased by 20% when mice were treated with Moab A7S8 compared to PBS. Furthermore, anti-oxLDL specific IgM and IgG antibody production increased significantly in the Moab A7S8 treated mice in comparison with PBS treated mice. Conclusion Our data show that passive immunization with a natural IgM antibody, directed to HOCl-oxLDL, can reduce atherosclerotic plaque development. We postulate that specific antibody therapy may be developed for use in human cardiovascular diseases. PMID:23874490

  12. Alpha/beta interferon receptor deficiency in mice significantly enhances susceptibility of the animals to pseudorabies virus infection.

    PubMed

    Wei, Jingyun; Ma, Yanmei; Wang, Long; Chi, Xiaojuan; Yan, Ruoxiang; Wang, Song; Li, Xinxin; Chen, Xiaoyong; Shao, Wenhan; Chen, Ji-Long

    2017-05-01

    Pseudorabies virus, one of the neurotropic viruses, can infect numerous mammals. In particular, pseudorabies virus infection of swine occurs worldwide, and is a major threat to swine industry. However, the mechanism underlying the interaction between pseudorabies virus and host innate immune system is not fully understood. Here, we investigated the involvement of interferon α/β (IFN-α/β) receptor (IFNAR) in the pathogenesis of pseudorabies virus in a mouse model. The results showed that IFNAR-deficient (IFNAR -/- ) mice were highly susceptible to the virus infection, as evidenced by markedly reduced survival rate of infected animals and increased viral replication. The expression of IFN-α/β and relevant interferon-stimulated genes in IFNAR -/- mice was significantly lower than that in wild-type (WT) littermates after the viral infection. Moreover, in response to the virus challenge, IFNAR -/- mice displayed elevated levels of inflammatory cytokines including interleukin 6 (IL-6) and IL-1β, and IFNAR -/- cells showed increased phosphorylation of STAT3. Collectively, these data reveal that the IFNAR -/- mice are more sensitive to pseudorabies virus infection than WT animals, and excessive IL-6/STAT3 response in IFNAR -/- mice may contribute to the pathogenesis. Our findings suggest that type I IFNs/IFNAR-dependent homeostatic control of the innate immunity is required for host defense against pseudorabies virus infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Dioxin-like PCB 126 Increases Systemic Inflammation and Accelerates Atherosclerosis in Lean LDL Receptor-Deficient Mice.

    PubMed

    Petriello, Michael C; Brandon, J Anthony; Hoffman, Jessie; Wang, Chunyan; Tripathi, Himi; Abdel-Latif, Ahmed; Ye, Xiang; Li, Xiangan; Yang, Liping; Lee, Eun; Soman, Sony; Barney, Jazmyne; Wahlang, Banrida; Hennig, Bernhard; Morris, Andrew J

    2018-04-01

    Exposure to dioxins and related persistent organic pollutants likely contributes to cardiovascular disease (CVD) risk through multiple mechanisms including the induction of chronic inflammation. Epidemiological studies have shown that leaner individuals may be more susceptible to the detrimental effects of lipophilic toxicants because they lack large adipose tissue depots that can accumulate and sequester these pollutants. This phenomenon complicates efforts to study mechanisms of pollutant-accelerated atherosclerosis in experimental animal models where high-fat feeding and adipose expansion limit the bioavailability of lipophilic pollutants. Here, we investigated whether a model dioxin-like pollutant, PCB 126, could increase inflammation and accelerate atherosclerosis in Ldlr-/- mice fed a low-fat atherogenic diet. We fed Ldlr-/- mice the Clinton/Cybulsky diet (10% kcal fat, 0.15% cholesterol) and sacrificed mice at 8, 10, or 12 weeks postPCB (2 doses of 1 μmol/kg) or vehicle gavage. To characterize this novel model, we examined the effects of PCB 126 on markers of systemic inflammation, hematological indices, fatty livers, and atherosclerotic lesion size. Mice exposed to PCB 126 exhibited significantly increased plasma inflammatory cytokine levels, increased circulating biomarkers of CVD, altered platelet, and red blood cell counts, increased accumulation of hepatic fatty acids, and accelerated atherosclerotic lesion formation in the aortic root. PCB 126 also increased circulating neutrophils, monocytes, and macrophages as determined by flow cytometry analysis. Exposure to dioxin-like PCB 126 increases inflammation and accelerates atherosclerosis in mice. This low-fat atherogenic diet may provide a useful tool to study the mechanisms linking exposure to lipophilic pollutants to increased risk of CVD.

  14. Mas receptor deficiency is associated with worsening of lipid profile and severe hepatic steatosis in ApoE-knockout mice.

    PubMed

    Silva, Analina R; Aguilar, Edenil C; Alvarez-Leite, Jacqueline I; da Silva, Rafaela F; Arantes, Rosa M E; Bader, Michael; Alenina, Natalia; Pelli, Graziano; Lenglet, Sébastien; Galan, Katia; Montecucco, Fabrizio; Mach, François; Santos, Sérgio H S; Santos, Robson A S

    2013-12-01

    The classical renin-angiotensin system pathway has been recently updated with the identification of additional molecules [such as angiotensin converting enzyme 2, ANG-(1-7), and Mas receptor] that might improve some pathophysiological processes in chronic inflammatory diseases. In the present study, we focused on the potential protective role of Mas receptor activation on mouse lipid profile, liver steatosis, and atherogenesis. Mas/apolipoprotein E (ApoE)-double-knockout (DKO) mice (based on C57BL/6 strain of 20 wk of age) were fed under normal diet and compared with aged-matched Mas and ApoE-single-knockout (KO), as well as wild-type mice. Mas/ApoE double deficiency was associated with increased serum levels of atherogenic fractions of cholesterol, triglycerides, and fasting glucose compared with wild-type or single KO. Serum levels of HDL or leptin in DKO were lower than in other groups. Hepatic lipid content as well as alanine aminotransferase serum levels were increased in DKO compared with wild-type or single-KO animals. Accordingly, the hepatic protein content of mediators related to atherosclerotic inflammation, such as peroxisome proliferator-activated receptor-α and liver X receptor, was altered in an adverse way in DKO compared with ApoE-KO. On the other hand, DKO mice did not display increased atherogenesis and intraplaque inflammation compared with ApoE-KO group. In conclusion, Mas deletion in ApoE-KO mice was associated with development of severe liver steatosis and dyslipidemia without affecting concomitant atherosclerosis. Mas receptor activation might represent promising strategies for future treatments targeting both hepatic and metabolic alterations in chronic conditions clustering these disorders.

  15. P2X(1) receptor-deficient mice establish the native P2X receptor and a P2Y6-like receptor in arteries.

    PubMed

    Vial, Catherine; Evans, Richard J

    2002-12-01

    The contribution of P2 receptors to vasoconstriction of mouse mesenteric arteries was determined using wild-type (WT) and P2X(1) receptor-deficient (KO) animals. alpha,beta-methylene ATP (alpha,beta-meATP) and ATP evoked transient inward currents and constrictions of WT mesenteric arteries. In contrast, alpha,beta-meATP (100 microM) and ATP (100 microM) failed to evoke responses in KO arteries from a range of vascular beds. Nerve stimulation (100 pulses at 10 Hz) evoked constrictions of mesenteric arteries. For WT arteries, the P2 receptor antagonist pyridoxalphosphate-6-azophenyl-2'-5'-disulfonate (PPADS) (30 microM) reduced the amplitude of response by approximately 50%; the residual constriction was abolished by prazosin (0.1 microM). In KO mice, vasoconstriction induced by nerve stimulation was reduced in amplitude by approximately 50%, unaffected by PPADS, but was abolished by prazosin. ADP (1 mM) (a P2Y(1), P2Y(12), and P2Y(13) receptor agonist) was ineffective. Because ATP had no effect on mesenteric artery tone from KO mice, this rules out the contribution of P2Y(2) receptors. The P2Y(4) receptor agonist ITP also failed to contract mesenteric arteries. However, UTP and UDP evoked sustained contractions of mesenteric arteries with similar potency (EC(50) approximately 10 microM). Complementary studies using reverse-transcriptase polymerase chain reaction showed that mesenteric arteries express P2Y(1), P2Y(2), and P2Y(6) receptors. These results demonstrate that homomeric P2X(1) receptors underlie the artery smooth muscle P2X receptor phenotype and contribute approximately 50% to sympathetic neurogenic vasoconstriction and indicate the presence of a UTP- and UDP-sensitive P2Y(6)-like receptor, but not vasoconstrictor P2Y(2) or P2Y(4) receptors, on mouse mesenteric arteries.

  16. Viral Infection of the Central Nervous System Exacerbates Interleukin-10 Receptor Deficiency-Mediated Colitis in SJL Mice

    PubMed Central

    Uhde, Ann-Kathrin; Herder, Vanessa; Akram Khan, Muhammad; Ciurkiewicz, Malgorzata; Schaudien, Dirk; Teich, René; Floess, Stefan; Baumgärtner, Wolfgang

    2016-01-01

    Theiler´s murine encephalomyelitis virus (TMEV)-infection is a widely used animal model for studying demyelinating disorders, including multiple sclerosis (MS). The immunosuppressive cytokine Interleukin (IL)-10 counteracts hyperactive immune responses and critically controls immune homeostasis in infectious and autoimmune disorders. In order to investigate the effect of signaling via Interleukin-10 receptor (IL-10R) in infectious neurological diseases, TMEV-infected SJL mice were treated with IL-10R blocking antibody (Ab) in the acute and chronic phase of the disease. The findings demonstrate that (i) Ab-mediated IL-10 neutralization leads to progressive colitis with a reduction in Foxp3+ regulatory T cells and increased numbers of CD8+CD44+ memory T cells as well as activated CD4+CD69+ and CD8+CD69+ T cells in uninfected mice. (ii) Concurrent acute TMEV-infection worsened enteric disease-mediated by IL-10R neutralization. Virus-triggered effects were associated with an enhanced activation of CD4+ T helper cells and CD8+ cytotoxic T lymphocytes and augmented cytokine expression. By contrast, (iii) IL-10R neutralization during chronic TMEV-infection was not associated with enhanced peripheral immunopathology but an increased CD3+ T cell influx in the spinal cord. IL-10R neutralization causes a breakdown in peripheral immune tolerance in genetically predisposed mice, which leads to immune-mediated colitis, resembling inflammatory bowel disease. Hyperactive immune state following IL-10R blockade is enhanced by central nervous system-restricted viral infection in a disease phase-dependent manner. PMID:27611574

  17. Dipeptidyl-peptidase-4 inhibitor, alogliptin, attenuates arterial inflammation and neointimal formation after injury in low-density lipoprotein (LDL) receptor-deficient mice.

    PubMed

    Akita, Koji; Isoda, Kikuo; Shimada, Kazunori; Daida, Hiroyuki

    2015-03-13

    The results of recent studies suggest that dipeptidyl-peptidase-4 inhibitors have antiatherogenic effects. However, whether or not dipeptidyl-peptidase-4 inhibitors could suppress arterial inflammation and intimal hyperplasia after injury remains undetermined. The present study aims to clarify the anti-inflammatory effects of the dipeptidyl-peptidase-4 inhibitor, alogliptin (AGP), on the arteries of atherogenic low-density lipoprotein receptor-deficient (LKO) mice. We compared intimal hyperplasia in LKO mice 2 weeks after femoral artery injury using an external vascular cuff model. All mice received oral injection of AGP (20 mg/kg per day) or normal saline (control) once daily for 14 days. Fasting blood sugar levels, serum cholesterol levels, or blood pressure did not significantly differ between the 2 groups. Plasma levels of active glucagon-like peptide-1 were higher in the AGP than in the control LKO mice (22.2±1.9 versus 15.6±0.9 pg/mL; P<0.05). Compared with saline, AGP significantly reduced intimal hyperplasia (1087±127 versus 1896±140 μm(2); P<0.001) as well as the intima/media ratio (0.08±0.01 versus 0.16±0.02; P<0.001). Immunostaining showed that AGP reduced proliferating cells (proliferating cell nuclear antigen-positive nuclei; P<0.001), percent smooth-muscle cell area (α-SMA-positive cells; P<0.001), inflammatory cells infiltration (lymphocyte antigen 6 complex-positive cells; P<0.05), tumor necrosis factor-α expression (P<0.05), and percent phospho-NF-κB-positive cell compared with saline. Levels of tumor necrosis factor -α (0.5-fold P<0.05), monocyte chemoattractant protein 1 (0.3-fold P<0.01), and interleukin-1β (0.2-fold P<0.05) mRNA were lower in the injured arteries of the AGP than in the control group. AGP appeared to suppress neointimal formation by inhibiting inflammation, independently of its effects on glucose or cholesterol metabolism in atherogenic LKO mice. © 2015 The Authors. Published on behalf of the American Heart

  18. Detection of early stage atherosclerotic plaques using PET and CT fusion imaging targeting P-selectin in low density lipoprotein receptor-deficient mice

    SciTech Connect

    Nakamura, Ikuko, E-mail: nakamuri@riken.jp; Department of Cardiovascular Medicine, Saga University, Saga; Hasegawa, Koki

    2013-03-29

    Highlights: ► P-selectin regulates leukocyte recruitment as an early stage event of atherogenesis. ► We developed an antibody-based molecular imaging probe targeting P-selectin for PET. ► This is the first report on successful PET imaging for delineation of P-selectin. ► P-selectin is a candidate target for atherosclerotic plaque imaging by clinical PET. -- Abstract: Background: Sensitive detection and qualitative analysis of atherosclerotic plaques are in high demand in cardiovascular clinical settings. The leukocyte–endothelial interaction mediated by an adhesion molecule P-selectin participates in arterial wall inflammation and atherosclerosis. Methods and results: A {sup 64}Cu-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid conjugated anti-P-selectin monoclonal antibody ({sup 64}Cu-DOTA-anti-P-selectinmore » mAb) probe was prepared by conjugating an anti-P-selectin monoclonal antibody with DOTA followed by {sup 64}Cu labeling. Thirty-six hours prior to PET and CT fusion imaging, 3 MBq of {sup 64}Cu-DOTA-anti-P-selectin mAb was intravenously injected into low density lipoprotein receptor-deficient Ldlr-/- mice. After a 180 min PET scan, autoradiography and biodistribution of {sup 64}Cu-DOTA-anti-P-selectin monoclonal antibody was examined using excised aortas. In Ldlr-/- mice fed with a high cholesterol diet for promotion of atherosclerotic plaque development, PET and CT fusion imaging revealed selective and prominent accumulation of the probe in the aortic root. Autoradiography of aortas that demonstrated probe uptake into atherosclerotic plaques was confirmed by Oil red O staining for lipid droplets. In Ldlr-/- mice fed with a chow diet to develop mild atherosclerotic plaques, probe accumulation was barely detectable in the aortic root on PET and CT fusion imaging. Probe biodistribution in aortas was 6.6-fold higher in Ldlr-/- mice fed with a high cholesterol diet than in those fed with a normal chow diet. {sup 64}Cu-DOTA-anti-P-selectin m

  19. Vaccination using oxidized low-density lipoprotein-pulsed dendritic cells reduces atherosclerosis in LDL receptor-deficient mice.

    PubMed

    Habets, Kim L L; van Puijvelde, Gijs H M; van Duivenvoorde, Leonie M; van Wanrooij, Eva J A; de Vos, Paula; Tervaert, Jan-Willem Cohen; van Berkel, Theo J C; Toes, Rene E M; Kuiper, Johan

    2010-02-01

    Modification of lipoproteins plays an important role in the development of atherosclerosis. Oxidatively modified low-density lipoprotein (oxLDL) has a number of pro-inflammatory effects, whereas immunization with various forms of oxLDL is able to reduce atherosclerosis. The uptake of modified LDL by dendritic cells (DCs) and the presentation of epitopes thereof may form an important step in the immunomodulatory effects of LDL. In this study, we transferred oxLDL-pulsed mature DCs (mDCs) to LDL receptor-null (LDLr(-/-)) mice and examined the effects on atherosclerosis. Bone marrow-derived DCs were cultured for 10 days in the presence of granulocyte-macrophage colony-stimulating factor. Immature DCs were matured by lipopolysaccharide and pulsed with copper-oxidized LDL. These mDCs were transferred three times to LDLr(-/-) mice before the induction of atherosclerosis by Western-type diet feeding. The transfer of oxLDL-pulsed mDCs resulted in an 87% reduction in carotid artery lesion size (P < 0.001) with a concurrent increase in plaque stability, whereas treatment using mDCs pulsed with the atherosclerosis-irrelevant antigen, ovalbumin, did not influence lesion size or stability. Furthermore, the vaccination procedure resulted in the induction of oxLDL-specific T cells with a reduced Th1 profile and an increase in oxLDL-specific IgG levels, which contributed to a reduction in foam cell formation. These data indicate that vaccination with oxLDL-pulsed mDCs provides a novel and powerful strategy for the immunomodulation of atherosclerosis.

  20. Proximal tubule-dominant transfer of AT1a receptors induces blood pressure responses to intracellular angiotensin II in AT1a receptor-deficient mice

    PubMed Central

    Li, Xiao C.

    2013-01-01

    The role of intracellular ANG II in proximal tubules of the kidney remains poorly understood. We tested the hypothesis that proximal tubule-dominant transfer of AT1a receptors in the cortex mediates intracellular ANG II-induced blood pressure responses in AT1a receptor-deficient (Agtr1a-/-) mice. A GFP-tagged AT1a receptor, AT1aR/GFP, and an enhanced cyan fluorescent intracellular ANG II fusion protein, ECFP/ANG II, were expressed in proximal tubules of Agtr1a-/- mouse kidneys via the adenoviral transfer using a sodium and glucose cotransporter 2 promoter. Transfer of AT1aR/GFP alone or with ECFP/ANG II induced proximal tubule-dominant expression of AT1aR/GFP and/or ECFP/ANG II with a peak response at 2 wk. No significant AT1aR/GFP and/or ECFP/ANG II expression was observed in the glomeruli, medulla, or extrarenal tissues. Transfer of AT1aR/GFP alone, but not ECFP/ANG II, increased systolic blood pressure by 12 ± 2 mmHg by day 14 (n = 9, P < 0.01). However, cotransfer of AT1aR/GFP with ECFP/ANG II increased blood pressure by 18 ± 2 mmHg (n = 12, P < 0.01). Twenty-four hour urinary sodium excretion was decreased by day 7 with proximal tubule-dominant transfer of AT1aR/GFP alone (P < 0.01) or with AT1aR/GFP and ECFP/ANG II cotransfer (P < 0.01). These responses were associated with twofold increases in phosphorylated ERK1/2, lysate, and membrane NHE-3 proteins in freshly isolated proximal tubules (P < 0.01). By contrast, transfer of control CMV-GFP (a recombinant human adenovirus type 5 expresses enhanced green fluorescent protein under the control of a cytomegalovirus (CMV) promoter), ECFP/ANG II, or a scrambled control ECFP/ANG IIc alone in proximal tubules had no effect on all indices. These results suggest that AT1a receptors and intracellular ANG II in proximal tubules of the kidney play an important physiological role in blood pressure regulation. PMID:23427083

  1. Causation of Acute Flaccid Paralysis by Myelitis and Myositis in Enterovirus-D68 Infected Mice Deficient in Interferon αβ/γ Receptor Deficient Mice

    PubMed Central

    Morrey, John D.; Wang, Hong; Hurst, Brett L.; Zukor, Katherine; Siddharthan, Venkatraman; Tarbet, E. Bart

    2018-01-01

    Enterovirus D68 (EV-D68) caused a large outbreak in the summer and fall of 2014 in the United States. It causes serious respiratory disease, but causation of associated paralysis is controversial, because the virus is not routinely identified in cerebrospinal fluid. To establish clinical correlates with human disease, we evaluated EV-D68 infection in non-lethal paralysis mouse models. Ten-day-old mice lacking interferon responses were injected intraperitoneally with the virus. Paralysis developed in hindlimbs. After six weeks of paralysis, the motor neurons were depleted due to viral infection. Hindlimb muscles were also infected and degenerating. Even at the earliest stage of paralysis, muscles were still infected and were degenerating, in addition to presence of virus in the spinal cord. To model natural respiratory infection, five-day-old mice were infected intranasally with EV-D68. Two of the four infected mice developed forelimb paralysis. The affected limbs had muscle disease, but no spinal cord infection was detected. The unique contributions of this study are that EV-D68 causes paralysis in mice, and that causation by muscle disease, with or without spinal cord disease, may help to resolve the controversy that the virus can cause paralysis, even if it cannot be identified in cerebrospinal fluid. PMID:29329211

  2. Causation of Acute Flaccid Paralysis by Myelitis and Myositis in Enterovirus-D68 Infected Mice Deficient in Interferon αβ/γ Receptor Deficient Mice.

    PubMed

    Morrey, John D; Wang, Hong; Hurst, Brett L; Zukor, Katherine; Siddharthan, Venkatraman; Van Wettere, Arnaud J; Sinex, Donal G; Tarbet, E Bart

    2018-01-12

    Enterovirus D68 (EV-D68) caused a large outbreak in the summer and fall of 2014 in the United States. It causes serious respiratory disease, but causation of associated paralysis is controversial, because the virus is not routinely identified in cerebrospinal fluid. To establish clinical correlates with human disease, we evaluated EV-D68 infection in non-lethal paralysis mouse models. Ten-day-old mice lacking interferon responses were injected intraperitoneally with the virus. Paralysis developed in hindlimbs. After six weeks of paralysis, the motor neurons were depleted due to viral infection. Hindlimb muscles were also infected and degenerating. Even at the earliest stage of paralysis, muscles were still infected and were degenerating, in addition to presence of virus in the spinal cord. To model natural respiratory infection, five-day-old mice were infected intranasally with EV-D68. Two of the four infected mice developed forelimb paralysis. The affected limbs had muscle disease, but no spinal cord infection was detected. The unique contributions of this study are that EV-D68 causes paralysis in mice, and that causation by muscle disease, with or without spinal cord disease, may help to resolve the controversy that the virus can cause paralysis, even if it cannot be identified in cerebrospinal fluid.

  3. Compared with saturated fatty acids, dietary monounsaturated fatty acids and carbohydrates increase atherosclerosis and VLDL cholesterol levels in LDL receptor-deficient, but not apolipoprotein E-deficient, mice

    PubMed Central

    Merkel, Martin; Velez-Carrasco, Wanda; Hudgins, Lisa C.; Breslow, Jan L.

    2001-01-01

    Heart-healthy dietary recommendations include decreasing the intake of saturated fatty acids (SFA). However, the relative benefit of replacing SFA with monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), or carbohydrates (CARB) is still being debated. We have used two mouse models of atherosclerosis, low density lipoprotein receptor-deficient (LDLRKO) and apolipoprotein E-deficient (apoEKO) mice to measure the effects of four isocaloric diets enriched with either SFA, MUFA, PUFA, or CARB on atherosclerotic lesion area and lipoprotein levels. In LDLRKO mice, compared with the SFA diet, the MUFA and CARB diets significantly increased atherosclerosis in both sexes, but the PUFA diet had no effect. The MUFA and CARB diets also increased very low density lipoprotein-cholesterol (VLDL-C) and LDL-cholesterol (LDL-C) in males and VLDL-C levels in females. Analysis of data from LDLRKO mice on all diets showed that atherosclerotic lesion area correlated positively with VLDL-C levels (males: r = 0.47, P < 0.005; females: r = 0.52, P < 0.001). In contrast, in apoEKO mice there were no significant dietary effects on atherosclerosis in either sex. Compared with the SFA diet, the CARB diet significantly decreased VLDL-C in males and the MUFA, PUFA, and CARB diets decreased VLDL-C and the CARB diet decreased LDL-C in females. In summary, in LDLRKO mice the replacement of dietary SFA by either MUFA or CARB causes a proportionate increase in both atherosclerotic lesion area and VLDL-C. There were no significant dietary effects on atherosclerotic lesion area in apoEKO mice. These results are surprising and suggest that, depending on the underlying genotype, dietary MUFA and CARB can actually increase atherosclerosis susceptibility, probably by raising VLDL-C levels through a non-LDL receptor, apoE-dependent pathway. PMID:11606787

  4. Compared with saturated fatty acids, dietary monounsaturated fatty acids and carbohydrates increase atherosclerosis and VLDL cholesterol levels in LDL receptor-deficient, but not apolipoprotein E-deficient, mice.

    PubMed

    Merkel, M; Velez-Carrasco, W; Hudgins, L C; Breslow, J L

    2001-11-06

    Heart-healthy dietary recommendations include decreasing the intake of saturated fatty acids (SFA). However, the relative benefit of replacing SFA with monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), or carbohydrates (CARB) is still being debated. We have used two mouse models of atherosclerosis, low density lipoprotein receptor-deficient (LDLRKO) and apolipoprotein E-deficient (apoEKO) mice to measure the effects of four isocaloric diets enriched with either SFA, MUFA, PUFA, or CARB on atherosclerotic lesion area and lipoprotein levels. In LDLRKO mice, compared with the SFA diet, the MUFA and CARB diets significantly increased atherosclerosis in both sexes, but the PUFA diet had no effect. The MUFA and CARB diets also increased very low density lipoprotein-cholesterol (VLDL-C) and LDL-cholesterol (LDL-C) in males and VLDL-C levels in females. Analysis of data from LDLRKO mice on all diets showed that atherosclerotic lesion area correlated positively with VLDL-C levels (males: r = 0.47, P < 0.005; females: r = 0.52, P < 0.001). In contrast, in apoEKO mice there were no significant dietary effects on atherosclerosis in either sex. Compared with the SFA diet, the CARB diet significantly decreased VLDL-C in males and the MUFA, PUFA, and CARB diets decreased VLDL-C and the CARB diet decreased LDL-C in females. In summary, in LDLRKO mice the replacement of dietary SFA by either MUFA or CARB causes a proportionate increase in both atherosclerotic lesion area and VLDL-C. There were no significant dietary effects on atherosclerotic lesion area in apoEKO mice. These results are surprising and suggest that, depending on the underlying genotype, dietary MUFA and CARB can actually increase atherosclerosis susceptibility, probably by raising VLDL-C levels through a non-LDL receptor, apoE-dependent pathway.

  5. Antithrombic and anti-atherogenic effects of partially defatted flaxseed meal using a laser-induced thrombosis test in apolipoprotein E and low-density lipoprotein receptor deficient mice.

    PubMed

    Sano, Takashi; Oda, Etsuko; Yamashita, Takatoshi; Shiramasa, Hiroshi; Ijiri, Yoshinobu; Yamashita, Tsutomu; Yamamoto, Junichiro

    2003-12-01

    Atherothrombosis can be regarded as a 'life-style related disease' of which diet is one of the important risk factors. The prophylactic effect of partially defatted flaxseed meal (PDFM) on atherothrombosis has not yet been studied. The aim of this study was to assess the effect of PDFM and a lignan from flaxseed, secoisolariciresinol diglucoside (SDG), on thrombosis and atherogenesis. An earlier developed test, the quantitative assessment of laser-induced thrombus formation in the carotid artery of apolipoprotein E and low-density lipoprotein receptor deficient mice was used in this study. Thrombotic and atherosclerotic status was assessed in mice kept on a high-fat diet for 8 weeks (40% in energy). The diet contained 0.05% cholesterol alone (control) or the same cholesterol with added PDFM (5% w/w; 8.3 g/kg body weight per day) or SDG (0.06% w/w; 100 mg/kg body weight per day). PDFM showed antithrombotic (P < 0.01) and anti-atherogenic effect (P < 0.01). SDG did not affect either atherogenesis or thrombosis. This study suggests that dietary intake of PDFM can be beneficial in reducing the risk of high-fat-induced atherothrombosis.

  6. Sex differences between CRF1 receptor deficient mice following naloxone-precipitated morphine withdrawal in a conditioned place aversion paradigm: implication of HPA axis.

    PubMed

    García-Carmona, Juan-Antonio; Baroja-Mazo, Alberto; Milanés, María-Victoria; Laorden, María Luisa

    2015-01-01

    Extinction period of positive affective memory of drug taking and negative affective memory of drug withdrawal, as well as the different response of men and women might be important for the clinical treatment of drug addiction. We investigate the role of corticotropin releasing factor receptor type one (CRF1R) and the different response of male and female mice in the expression and extinction of the aversive memory. We used genetically engineered male and female mice lacking functional CRF1R. The animals were rendered dependent on morphine by intraperitoneally injection of increasing doses of morphine (10-60 mg/kg). Negative state associated with naloxone (1 mg/kg s.c.)-precipitated morphine withdrawal was examined by using conditioned place aversion (CPA) paradigm. No sex differences for CPA expression were found in wild-type (n = 29) or CRF1R knockout (KO) mice (n = 29). However, CRF1R KO mice presented less aversion score than wild-type mice, suggesting that CRF1R KO mice were less responsive than wild-type to continuous associations between drug administration and environmental stimuli. In addition, CPA extinction was delayed in wild-type and CRF1R KO male mice compared with females of both genotypes. The genetic disruption of the CRF1R pathway decreased the period of extinction in males and females suggesting that CRF/CRF1R is implicated in the duration of aversive memory. Our results also showed that the increase in adrenocorticotropic hormone (ACTH) levels observed in wild-type (n = 11) mice after CPA expression, were attenuated in CRF1R KO mice (n = 10). In addition, ACTH returned to the baseline levels in males and females once CPA extinction was finished. These results suggest that, at least, CPA expression is partially due to an increase in plasma ACTH levels, through activation of CRF1R, which can return when CPA extinction is finished.

  7. A role of IL-1 in MPTP-induced changes in striatal dopaminergic and serotoninergic transporter binding: clues from interleukin-1 type I receptor-deficient mice.

    PubMed

    Hébert, Guillaume; Mingam, Rozenn; Arsaut, Josette; Dantzer, Robert; Demotes-Mainard, Jacques

    2005-05-20

    In mice, the MPTP-induced striatal dopaminergic denervation is followed by a spontaneous partial DAT recovery and by serotoninergic hyperinnervation. We show that IL-1RI-deficient mice have a higher DAT decrease in the ventromedial striatum after MPTP and a higher basal serotoninergic innervation of the whole striatum. These data point to a possible role of IL-1RI in the early MPTP-induced structural or functional remodeling of the nigrostriatal dopamine system.

  8. Glycogen synthase kinase 3α deficiency attenuates atherosclerosis and hepatic steatosis in high fat diet-fed low density lipoprotein receptor-deficient mice.

    PubMed

    Banko, Nicole S; McAlpine, Cameron S; Venegas-Pino, Daniel E; Raja, Preeya; Shi, Yuanyuan; Khan, Mohammad I; Werstuck, Geoff H

    2014-12-01

    Studies have implicated signaling through glycogen synthase kinase (GSK) 3α/β in the activation of pro-atherogenic pathways and the accelerated development of atherosclerosis. By using a mouse model, we examined the role of GSK3α in the development and progression of accelerated atherosclerosis. We crossed Gsk3a/GSK3α-knockout mice with low-density lipoprotein receptor (Ldlr) knockout mice. Five-week-old Ldlr(-/-);Gsk3a(+/+), Ldlr(-/-);Gsk3a(+/-), and Ldlr(-/-);Gsk3a(-/-) mice were fed a chow diet or a high-fat diet for 10 weeks and then sacrificed. GSK3α deficiency had no detectible effect on any measured parameters in chow-fed mice. High-fat-diet fed Ldlr(-/-) mice that were deficient for GSK3α had significantly less hepatic lipid accumulation and smaller atherosclerotic lesions (60% smaller in Ldlr(-/-);Gsk3a(+/-) mice, 80% smaller in Ldlr(-/-);Gsk3a(-/-) mice; P < 0.05), compared with Ldlr(-/-);Gsk3a(+/+) controls. GSK3α deficiency was associated with a significant increase in plasma IL-10 concentration and IL-10 expression in isolated macrophages. A twofold to threefold enhancement in endoplasmic reticulum stress-induced IL-10 expression was observed in Thp-1-derived macrophages that were pretreated with the GSK3α/β inhibitor CT99021. Together, these results suggest that GSK3α plays a pro-atherogenic role, possibly by mediating the effects of endoplasmic reticulum stress in the activation of pro-atherogenic pathways. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  9. Angiotensin II type 1a receptor-deficient mice develop angiotensin II-induced oxidative stress and DNA damage without blood pressure increase.

    PubMed

    Zimnol, Anna; Amann, Kerstin; Mandel, Philipp; Hartmann, Christina; Schupp, Nicole

    2017-12-01

    Hypertensive patients have an increased risk of developing kidney cancer. We have shown in vivo that besides elevating blood pressure, angiotensin II causes DNA damage dose dependently. Here, the role of blood pressure in the formation of DNA damage is studied. Mice lacking one of the two murine angiotensin II type 1 receptor (AT1R) subtypes, AT1aR, were equipped with osmotic minipumps, delivering angiotensin II during 28 days. Parameters of oxidative stress and DNA damage of kidneys and hearts of AT1aR-knockout mice were compared with wild-type (C57BL/6) mice receiving angiotensin II, and additionally, with wild-type mice treated with candesartan, an antagonist of both AT1R subtypes. In wild-type mice, angiotensin II induced hypertension, reduced kidney function, and led to a significant formation of reactive oxygen species (ROS). Furthermore, genomic damage was markedly increased in this group. All these responses to angiotensin II could be attenuated by concurrent administration of candesartan. In AT1aR-deficient mice treated with angiotensin II, systolic pressure was not increased, and renal function was not affected. However, angiotensin II still led to an increase of ROS in kidneys and hearts of these animals. Additionally, genomic damage in the form of double-strand breaks was significantly induced in kidneys of AT1aR-deficient mice. Our results show that angiotensin II induced ROS production and DNA damage even without the presence of AT1aR and independently of blood pressure changes. Copyright © 2017 the American Physiological Society.

  10. α7 nicotinic ACh receptor-deficient mice exhibit sustained attention impairments that are reversed by β2 nicotinic ACh receptor activation.

    PubMed

    Kolisnyk, Benjamin; Al-Onaizi, Mohammed A; Prado, Vania F; Prado, Marco A M

    2015-10-01

    Disruptions of executive function, including attentional deficits, are a hallmark of a number of diseases. ACh in the prefrontal cortex regulates attentive behaviour; however, the role of α7 nicotinic ACh receptor (α7nAChR) in attention is contentious. In order to probe attention, we trained both wild-type and α7nAChR knockout mice on a touch screen-based five-choice serial reaction time task (5-CSRT). Following training procedures, we then tested sustained attention using a probe trial experiment. To further differentiate the role of specific nicotinic receptors in attention, we then tested the effects of both α7nAChR and β2nAChR agonists on the performance of both wild-type and knockout mice on the 5-CSRT task. At low doses, α7nAChR agonists improved attentional performance of wild-type mice, while high doses had deleterious effects on attention. α7nAChR knockout mice displayed deficits in sustained attention that were not ameliorated by α7nAChR agonists. However, these deficits were completely reversed by the administration of a β2nAChR agonist. Furthermore, administration of a β2nAChR agonist in α7nAChR knockout mice elicited similar biochemical response in the prefrontal cortex as the administration of α7nAChR agonists in wild-type mice. Our experiments reveal an intricate relationship between distinct nicotinic receptors to regulate attentional performance and provide the basis for targeting β2nAChRs pharmacologically to decrease attentional deficits due to a dysfunction in α7nAChRs. © 2015 The British Pharmacological Society.

  11. Depletion of B2 but Not B1a B Cells in BAFF Receptor-Deficient ApoE−/− Mice Attenuates Atherosclerosis by Potently Ameliorating Arterial Inflammation

    PubMed Central

    Kyaw, Tin; Tay, Christopher; Hosseini, Hamid; Kanellakis, Peter; Gadowski, Tahlia; MacKay, Fabeinne; Tipping, Peter

    2012-01-01

    We have recently identified conventional B2 cells as atherogenic and B1a cells as atheroprotective in hypercholesterolemic ApoE−/− mice. Here, we examined the development of atherosclerosis in BAFF-R deficient ApoE−/− mice because B2 cells but not B1a cells are selectively depleted in BAFF-R deficient mice. We fed BAFF-R−/− ApoE−/− (BaffR.ApoE DKO) and BAFF-R+/+ApoE−/− (ApoE KO) mice a high fat diet (HFD) for 8-weeks. B2 cells were significantly reduced by 82%, 81%, 94%, 72% in blood, peritoneal fluid, spleen and peripheral lymph nodes respectively; while B1a cells and non-B lymphocytes were unaffected. Aortic atherosclerotic lesions assessed by oil red-O stained-lipid accumulation and CD68+ macrophage accumulation were decreased by 44% and 50% respectively. B cells were absent in atherosclerotic lesions of BaffR.ApoE DKO mice as were IgG1 and IgG2a immunoglobulins produced by B2 cells, despite low but measurable numbers of B2 cells and IgG1 and IgG2a immunoglobulin concentrations in plasma. Plasma IgM and IgM deposits in atherosclerotic lesions were also reduced. BAFF-R deficiency in ApoE−/− mice was also associated with a reduced expression of VCAM-1 and fewer macrophages, dendritic cells, CD4+ and CD8+ T cell infiltrates and PCNA+ cells in lesions. The expression of proinflammatory cytokines, TNF-α, IL1-β and proinflammatory chemokine MCP-1 was also reduced. Body weight and plasma cholesterols were unaffected in BaffR.ApoE DKO mice. Our data indicate that B2 cells are important contributors to the development of atherosclerosis and that targeting the BAFF-R to specifically reduce atherogenic B2 cell numbers while preserving atheroprotective B1a cell numbers may be a potential therapeutic strategy to reduce atherosclerosis by potently reducing arterial inflammation. PMID:22238605

  12. piRNA-associated proteins and retrotransposons are differentially expressed in murine testis and ovary of aryl hydrocarbon receptor deficient mice

    PubMed Central

    Rico-Leo, Eva M.; Moreno-Marín, Nuria; González-Rico, Francisco J.; Barrasa, Eva; Ortega-Ferrusola, Cristina; Martín-Muñoz, Patricia; Sánchez-Guardado, Luis O.; Llano, Elena; Alvarez-Barrientos, Alberto; Infante-Campos, Ascensión; Catalina-Fernández, Inmaculada; Hidalgo-Sánchez, Matías; de Rooij, Dirk G.; Pendás, Alberto M.; Peña, Fernando J.; Merino, Jaime M.

    2016-01-01

    Previous studies suggested that the aryl hydrocarbon receptor (AhR) contributes to mice reproduction and fertility. However, the mechanisms involved remain mostly unknown. Retrotransposon silencing by Piwi-interacting RNAs (piRNAs) is essential for germ cell maturation and, remarkably, AhR has been identified as a regulator of murine B1-SINE retrotransposons. Here, using littermate AhR+/+ and AhR−/− mice, we report that AhR regulates the general course of spermatogenesis and oogenesis by a mechanism likely to be associated with piRNA-associated proteins, piRNAs and retrotransposons. piRNA-associated proteins MVH and Miwi are upregulated in leptotene to pachytene spermatocytes with a more precocious timing in AhR−/− than in AhR+/+ testes. piRNAs and transcripts from B1-SINE, LINE-1 and IAP retrotransposons increased at these meiotic stages in AhR-null testes. Moreover, B1-SINE transcripts colocalize with MVH and Miwi in leptonema and pachynema spermatocytes. Unexpectedly, AhR−/− males have increased sperm counts, higher sperm functionality and enhanced fertility than AhR+/+ mice. In contrast, piRNA-associated proteins and B1-SINE and IAP-derived transcripts are reduced in adult AhR−/− ovaries. Accordingly, AhR-null female mice have lower numbers of follicles when compared with AhR+/+ mice. Thus, AhR deficiency differentially affects testis and ovary development possibly by a process involving piRNA-associated proteins, piRNAs and transposable elements. PMID:28003471

  13. Insulin-Like Growth Factor 1 Receptor Deficiency in Macrophages Accelerates Atherosclerosis and Induces an Unstable Plaque Phenotype in Apolipoprotein E Deficient Mice

    PubMed Central

    Higashi, Yusuke; Sukhanov, Sergiy; Shai, Shaw-Yung; Danchuk, Svitlana; Tang, Richard; Snarski, Patricia; Li, Zhaohui; Lobelle-Rich, Patricia; Wang, Meifang; Wang, Derek; Yu, Hong; Korthuis, Ronald; Delafontaine, Patrice

    2016-01-01

    Background We have previously shown that systemic infusion of insulin-like growth factor-1 (IGF-1) exerts anti-inflammatory and anti-oxidant effects and reduces atherosclerotic burden in apolipoprotein E (Apoe) deficient mice. Monocytes/macrophages express high levels of IGF-1 receptor (IGF1R) and play a pivotal role in atherogenesis but the potential effects of IGF-1 on their function are unknown. Methods and Results To determine mechanisms whereby IGF-1 reduces atherosclerosis and to explore the potential involvement of monocytes/macrophages, we created monocyte/ macrophage specific IGF1R knockout (MΦ-IGF1R-KO) mice on Apoe−/− background. We assessed atherosclerotic burden, plaque features of stability, and monocyte recruitment to atherosclerotic lesions. Phenotypic changes of IGF1R-deficient macrophages were investigated in culture. MΦ-IGF1R-KO significantly increased atherosclerotic lesion formation, as assessed by Oil-red-O staining of en face aortae and aortic root cross-sections, and changed plaque composition to a less stable phenotype, characterized by increased macrophage and decreased α-smooth muscle actin-positive cell population, fibrous cap thinning, and decreased collagen content. Brachiocephalic artery lesions of MΦ-IGF1R-KO mice had histological features implying plaque vulnerability. Macrophages isolated from MΦ-IGF1R-KO mice showed enhanced proinflammatory responses upon stimulation by IFNγ and oxidized LDL and elevated antioxidant gene expression levels. Moreover, IGF1R deficient macrophages had decreased expression of ABCA1 and ABCG1 and reduced lipid efflux. Conclusions Our data indicate that macrophage IGF1R signaling suppresses macrophage and foam cell accumulation in lesions and reduces plaque vulnerability, providing a novel mechanism whereby IGF-1 exerts anti-atherogenic effects. PMID:27154724

  14. 3,5,3′-Triiodo-L-Thyronine- and 3,5-Diiodo-L-Thyronine- Affected Metabolic Pathways in Liver of LDL Receptor Deficient Mice

    PubMed Central

    Moreno, Maria; Silvestri, Elena; Coppola, Maria; Goldberg, Ira J.; Huang, Li-Shin; Salzano, Anna M.; D'Angelo, Fulvio; Ehrenkranz, Joel R.; Goglia, Fernando

    2016-01-01

    3,5,3′-triiodo-L-thyronine (T3) and 3,5-diiodo-L-thyronine (T2), when administered to a model of familial hypercholesterolemia, i.e., low density lipoprotein receptor (LDLr)-knockout (Ldlr−/−) mice fed with a Western type diet (WTD), dramatically reduce circulating total and very low-density lipoprotein/LDL cholesterol with decreased liver apolipoprotein B (ApoB) production. The aim of the study was to highlight putative molecular mechanisms to manage cholesterol levels in the absence of LDLr. A comprehensive comparative profiling of changes in expression of soluble proteins in livers from Ldlr−/− mice treated with either T3 or T2 was performed. From a total proteome of 450 liver proteins, 25 identified proteins were affected by both T2 and T3, 18 only by T3 and 9 only by T2. Using in silico analyses, an overlap was observed with 11/14 pathways common to both iodothyronines, with T2 and T3 preferentially altering sub-networks centered around hepatocyte nuclear factor 4 α (HNF4α) and peroxisome proliferator-activated receptor α (PPARα), respectively. Both T2 and T3 administration significantly reduced nuclear HNF4α protein content, while T2, but not T3, decreased the expression levels of the HNFα transcriptional coactivator PGC-1α. Lower PPARα levels were found only following T3 treatment while both T3 and T2 lowered liver X receptor α (LXRα) nuclear content. Overall, this study, although it was not meant to investigate the use of T2 and T3 as a therapeutic agent, provides novel insights into the regulation of hepatic metabolic pathways involved in T3- and T2-driven cholesterol reduction in Ldlr−/− mice. PMID:27909409

  15. Gamma interferon (IFN-γ) receptor restricts systemic dengue virus replication and prevents paralysis in IFN-α/β receptor-deficient mice.

    PubMed

    Prestwood, Tyler R; Morar, Malika M; Zellweger, Raphaël M; Miller, Robyn; May, Monica M; Yauch, Lauren E; Lada, Steven M; Shresta, Sujan

    2012-12-01

    We previously reported that mice lacking alpha/beta and gamma interferon receptors (IFN-α/βR and -γR) uniformly exhibit paralysis following infection with the dengue virus (DENV) clinical isolate PL046, while only a subset of mice lacking the IFN-γR alone and virtually no mice lacking the IFN-α/βR alone develop paralysis. Here, using a mouse-passaged variant of PL046, strain S221, we show that in the absence of the IFN-α/βR, signaling through the IFN-γR confers approximately 140-fold greater resistance against systemic vascular leakage-associated dengue disease and virtually complete protection from dengue-induced paralysis. Viral replication in the spleen was assessed by immunohistochemistry and flow cytometry, which revealed a reduction in the number of infected cells due to IFN-γR signaling by 2 days after infection, coincident with elevated levels of IFN-γ in the spleen and serum. By 4 days after infection, IFN-γR signaling was found to restrict DENV replication systemically. Clearance of DENV, on the other hand, occurred in the absence of IFN-γR, except in the central nervous system (CNS) (brain and spinal cord), where clearance relied on IFN-γ from CD8(+) T cells. These results demonstrate the roles of IFN-γR signaling in protection from initial systemic and subsequent CNS disease following DENV infection and demonstrate the importance of CD8(+) T cells in preventing DENV-induced CNS disease.

  16. Gamma Interferon (IFN-γ) Receptor Restricts Systemic Dengue Virus Replication and Prevents Paralysis in IFN-α/β Receptor-Deficient Mice

    PubMed Central

    Prestwood, Tyler R.; Morar, Malika M.; Zellweger, Raphaël M.; Miller, Robyn; May, Monica M.; Yauch, Lauren E.; Lada, Steven M.

    2012-01-01

    We previously reported that mice lacking alpha/beta and gamma interferon receptors (IFN-α/βR and -γR) uniformly exhibit paralysis following infection with the dengue virus (DENV) clinical isolate PL046, while only a subset of mice lacking the IFN-γR alone and virtually no mice lacking the IFN-α/βR alone develop paralysis. Here, using a mouse-passaged variant of PL046, strain S221, we show that in the absence of the IFN-α/βR, signaling through the IFN-γR confers approximately 140-fold greater resistance against systemic vascular leakage-associated dengue disease and virtually complete protection from dengue-induced paralysis. Viral replication in the spleen was assessed by immunohistochemistry and flow cytometry, which revealed a reduction in the number of infected cells due to IFN-γR signaling by 2 days after infection, coincident with elevated levels of IFN-γ in the spleen and serum. By 4 days after infection, IFN-γR signaling was found to restrict DENV replication systemically. Clearance of DENV, on the other hand, occurred in the absence of IFN-γR, except in the central nervous system (CNS) (brain and spinal cord), where clearance relied on IFN-γ from CD8+ T cells. These results demonstrate the roles of IFN-γR signaling in protection from initial systemic and subsequent CNS disease following DENV infection and demonstrate the importance of CD8+ T cells in preventing DENV-induced CNS disease. PMID:22973027

  17. CRF1 receptor-deficiency increases cocaine reward.

    PubMed

    Contarino, Angelo; Kitchener, Pierre; Vallée, Monique; Papaleo, Francesco; Piazza, Pier-Vincenzo

    2017-05-01

    Stimulant drugs produce reward but also activate stress-responsive systems. The corticotropin-releasing factor (CRF) and the related hypothalamus-pituitary-adrenal (HPA) axis stress-responsive systems are activated by stimulant drugs. However, their role in stimulant drug-induced reward remains poorly understood. Herein, we report that CRF 1 receptor-deficient (CRF 1 -/-), but not wild-type, mice show conditioned place preference (CPP) responses to a relatively low cocaine dose (5 mg/kg, i.p.). Conversely, wild-type, but not CRF 1 -/-, mice display CPP responses to a relatively high cocaine dose (20 mg/kg, i.p.), indicating that CRF 1 receptor-deficiency alters the rewarding effects of cocaine. Acute pharmacological antagonism of the CRF 1 receptor by antalarmin also eliminates cocaine reward. Nevertheless, CRF 1 -/- mice display higher stereotypy responses to cocaine than wild-type mice. Despite the very low plasma corticosterone concentration, CRF 1 -/- mice show higher nuclear glucocorticoid receptor (GR) levels in the brain region of the hippocampus than wild-type mice. Full rescue of wild-type-like corticosterone and GR circadian rhythm and level in CRF 1 -/- mice by exogenous corticosterone does not affect CRF 1 receptor-dependent cocaine reward but induces stereotypy responses to cocaine. These results indicate a critical role for the CRF 1 receptor in cocaine reward, independently of the closely related HPA axis activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Relative Contribution of Dengue IgG Antibodies Acquired during Gestation or Breastfeeding in Mediating Dengue Disease Enhancement and Protection in Type I Interferon Receptor-Deficient Mice

    PubMed Central

    Lee, Pei Xuan; Ong, Li Ching; Libau, Eshele Anak; Alonso, Sylvie

    2016-01-01

    Dengue virus (DENV) causes a spectrum of diseases ranging from self-limiting dengue fever to severe conditions such as haemorrhagic fever and dengue shock syndrome. Antibody-dependent enhancement (ADE) is thought to explain the occurrence of severe dengue whereby pre-existing binding but non-neutralising antibodies enhance DENV infection. The ADE phenomenon is supported by epidemiological findings that infants that born to dengue immune mothers are at greater risk to develop severe dengue upon primary infection. The role of maternally acquired dengue-specific antibodies in disease enhancement was recently recapitulated in a mouse model where mice born to DENV1-immune mothers experienced enhanced disease severity upon DENV2 infection. Here, this study investigates the relative contribution of maternal dengue-specific antibodies acquired during gestation and breastfeeding in dengue disease. Using a surrogate breastfeeding mother experimental approach, we showed that majority of the maternal dengue-specific antibodies were acquired during breastfeeding and conferred an extended enhancement window. On the other hand, in the context of homologous infection, breastfeeding conferred protection. Furthermore, measurement of dengue-specific antibody titres over time in mice born to dengue immune mothers revealed a biphasic pattern of antibody decay as reported in humans. Our work provides evidence of the potential contribution of breast milk-acquired dengue-specific IgG antibodies in enhancement and protection against dengue. Should such contribution be established in humans as well, it may have important implications for the development of guidelines to dengue-immune breastfeeding mothers. PMID:27341339

  19. Establishment and characterization of DB-1: a leptin receptor-deficient murine macrophage cell line.

    PubMed

    Dib, Lea H; Ortega, M Teresa; Melgarejo, Tonatiuh; Chapes, Stephen K

    2016-08-01

    Metabolic and immune mediators activate many of the same signal transduction pathways. Therefore, molecules that regulate metabolism often affect immune responses. Leptin is an adipokine that exemplifies this interplay. Leptin is the body's major nutritional status sensor, but it also plays a key role in immune system regulation. To provide an in vitro tool to investigate the link between leptin and innate immunity, we immortalized and characterized a leptin receptor-deficient macrophage cell line, DB-1. The cell line was created using bone marrow cells from leptin receptor-deficient mice. Bone marrow cells were differentiated into macrophages by culturing them with recombinant mouse macrophage colony stimulating factor, and passaged when confluent for 6 months. The cells spontaneously immortalized at approximately passage 20. Cells were cloned twice by limiting dilution cloning prior to characterization. The macrophage cell line is diploid and grows at a linear rate for 4-5 days before reaching the growth plateau. The cells are MAC-2 and F4/80 positive and have phagocytic activity similar to primary macrophages from wild-type and leptin receptor-deficient mice. DB-1 cells were responsive to stimulation with interferon-γ as measured by increase in Nos2 transcript levels. In addition, DB-1 macrophages are not responsive to the chemotactic signaling of adipocyte conditioned media nor leptin when compared to primary WT macrophages. We believe that DB-1 cells provide a dependable tool to study the role of leptin or the leptin receptor in obesity-associated inflammation and immune system dysregulation.

  20. Physiological roles revealed by ghrelin and ghrelin receptor deficient mice

    USDA-ARS?s Scientific Manuscript database

    Ghrelin is a hormone made in the stomach and known primarily for its growth hormone releasing and orexigenic properties. Nevertheless, ghrelin through its receptor, the GHS-R1a, has been shown to exert many roles including regulation of glucose homeostasis, memory & learning, food addiction and neur...

  1. Brain Structure and Function Associated with Younger Adults in Growth Hormone Receptor-Deficient Humans.

    PubMed

    Nashiro, Kaoru; Guevara-Aguirre, Jaime; Braskie, Meredith N; Hafzalla, George W; Velasco, Rico; Balasubramanian, Priya; Wei, Min; Thompson, Paul M; Mather, Mara; Nelson, Marvin D; Guevara, Alexandra; Teran, Enrique; Longo, Valter D

    2017-02-15

    Growth hormone receptor deficiency (GHRD) results in short stature, enhanced insulin sensitivity, and low circulating levels of insulin and insulin-like growth factor 1 (IGF-1). Previous studies in mice and humans suggested that GHRD has protective effects against age-related diseases, including cancer and diabetes. Whereas GHRD mice show improved age-dependent cognitive performance, the effect of GHRD on human cognition remains unknown. Using MRI, we compared brain structure, function, and connectivity between 13 people with GHRD and 12 unaffected relatives. We assessed differences in white matter microstructural integrity, hippocampal volume, subregional volumes, and cortical thickness and surface area of selected regions. We also evaluated brain activity at rest and during a hippocampal-dependent pattern separation task. The GHRD group had larger surface areas in several frontal and cingulate regions and showed trends toward larger dentate gyrus and CA1 regions of the hippocampus. They had lower mean diffusivity in the genu of the corpus callosum and the anterior thalamic tracts. The GHRD group showed enhanced cognitive performance and greater task-related activation in frontal, parietal, and hippocampal regions compared with controls. Furthermore, they had greater functional synchronicity of activity between the precuneus and the rest of the default mode network at rest. The results suggest that, compared with controls, GHRD subjects have brain structure and function that are more consistent with those observed in younger adults reported in previous studies. Further investigation may lead to improved understanding of underlying mechanisms and could contribute to the identification of treatments for age-related cognitive deficits. SIGNIFICANCE STATEMENT People and mice with growth hormone receptor deficiency (GHRD or Laron syndrome) are protected against age-related diseases including cancer and diabetes. However, in humans, it is unknown whether cognitive

  2. Hexachlorobenzene stimulates uroporphyria in low affinity AHR mice without increasing CYP1A2

    SciTech Connect

    Gorman, Nadia; Department of Biochemistry, Dartmouth Medical School, Hanover, NH; Trask, Heidi S.

    2007-06-01

    Hexachlorobenzene (HCB), a weak ligand of the aryl hydrocarbon receptor (AHR), causes hepatic uroporphyrin (URO) accumulation (uroporphyria) in humans and animals. CYP1A2 has been shown to be necessary in the development of uroporphyria in mice. Using mice expressing the low affinity form of the AH receptor (AHRd), we investigated whether the enhancement of uroporphyria by HCB involves an obligatory increase in CYP1A2 as measured by specific enzyme assays and immunoblotting. We compared the ability of HCB, in combination with iron dextran and the porphyrin precursor, 5-aminolevulinate (ALA), to cause uroporphyria in a strain of mice (C57BL/6) which expresses the highmore » affinity form of the receptor (AHRb{sub 1}), with three strains of mice (SWR and two 129 sublines) expressing the low affinity AHRd. In C57BL/6 mice, HCB-enhanced uroporphyria was associated with a doubling of CYP1A2. HCB treatment produced uroporphyria in iron-loaded mice expressing AHRd, even though there was little or no increase in CYP1A2. Cyp1a2(-/-) mice in a 129 background were completely resistant to HCB-induced uroporphyria, and female Hfe(-/-) 129 mice, in which the levels of hepatic CYP1A2 were half of those of the male levels, responded poorly. The effect of exogenous iron, administered in the form of iron dextran, on HCB enhancement of uroporphryia could be replicated utilizing the endogenous hepatic iron accumulated in 129 Hfe(-/-) mice. In conclusion, some minimal basal expression of CYP1A2 is essential for HCB-mediated enhancement of uroporphyria, but increases in CYP1A2 above that level are not essential.« less

  3. Capillary Defects and Exaggerated Inflammatory Response in the Airways of EphA2-Deficient Mice

    PubMed Central

    Okazaki, Tatsuma; Ni, Amy; Baluk, Peter; Ayeni, Oluwasheyi A.; Kearley, Jennifer; Coyle, Anthony J.; Humbles, Alison; McDonald, Donald M.

    2009-01-01

    Both Eph receptors and ephrin ligands have been implicated in blood vessel and neuronal development. Recent studies suggested that EphA2 inhibition reduces tumor angiogenesis, but its role in blood vessel development and inflammation is unclear. We examined these issues using either airways of pathogen-free, EphA2-deficient mice at various ages or EphA2-deficient mice whose airways were inflamed by either Mycoplasma pulmonis infection or ovalbumin sensitization and challenge. EphA2-deficient mice had fewer capillaries, a greater number of endothelial sprouts, and greater capillary diameters than age-matched, wild-type control mice. Moreover, capillaries in EphA2-deficient mice had significantly less pericyte coverage, suggesting abnormal interactions between endothelial cells and pericytes. These differences were apparent in early postnatal life but decreased during progression into adulthood. In inflamed airways, significantly more angiogenesis and lymphangiogenesis, a greater number of infiltrating leukocytes, and higher expression levels of inflammatory cytokine mRNA were present in EphA2-deficient mice after M. pulmonis infection. Additionally, in allergic airway inflammation with ovalbumin sensitization and challenge, a greater number of lymphatic sprouts and infiltrating leukocytes, higher mRNA expression levels of TH2 cytokines and chemokines related to allergic airway inflammation, and enhanced airway hyper-responsiveness were present in EphA2-deficient mice. We conclude that defective pericyte coverage causes capillary defects, abundant endothelial sprouts, and thick capillary diameters in EphA2-deficient mice, indicating that these animals have exaggerated responses to airway inflammation. PMID:19443703

  4. Curcumin modulation of high fat diet-induced atherosclerosis and steatohepatosis in LDL receptor deficient mice

    USDA-ARS?s Scientific Manuscript database

    Consuming curcumin may benefit health by modulating lipid metabolism and suppressing atherogenesis. Fatty acid binding proteins (FABP-4/aP2) and CD36 expression are key factors in lipid accumulation in macrophages and foam cell formation in atherogenesis. Our earlier observations suggest that curcum...

  5. Adenosine A2A receptor antagonists are potential antidepressants: evidence based on pharmacology and A2A receptor knockout mice

    PubMed Central

    Yacoubi, Malika El; Ledent, Catherine; Parmentier, Marc; Bertorelli, Rosalia; Ongini, Ennio; Costentin, Jean; Vaugeois, Jean-Marie

    2001-01-01

    Adenosine, an ubiquitous neuromodulator, and its analogues have been shown to produce ‘depressant' effects in animal models believed to be relevant to depressive disorders, while adenosine receptor antagonists have been found to reverse adenosine-mediated ‘depressant' effect. We have designed studies to assess whether adenosine A2A receptor antagonists, or genetic inactivation of the receptor would be effective in established screening procedures, such as tail suspension and forced swim tests, which are predictive of clinical antidepressant activity. Adenosine A2A receptor knockout mice were found to be less sensitive to ‘depressant' challenges than their wildtype littermates. Consistently, the adenosine A2A receptor blockers SCH 58261 (1 – 10 mg kg−1, i.p.) and KW 6002 (0.1 – 10 mg kg−1, p.o.) reduced the total immobility time in the tail suspension test. The efficacy of adenosine A2A receptor antagonists in reducing immobility time in the tail suspension test was confirmed and extended in two groups of mice. Specifically, SCH 58261 (1 – 10 mg kg−1) and ZM 241385 (15 – 60 mg kg−1) were effective in mice previously screened for having high immobility time, while SCH 58261 at 10 mg kg−1 reduced immobility of mice that were selectively bred for their spontaneous ‘helplessness' in this assay. Additional experiments were carried out using the forced swim test. SCH 58261 at 10 mg kg−1 reduced the immobility time by 61%, while KW 6002 decreased the total immobility time at the doses of 1 and 10 mg kg−1 by 75 and 79%, respectively. Administration of the dopamine D2 receptor antagonist haloperidol (50 – 200 μg kg−1 i.p.) prevented the antidepressant-like effects elicited by SCH 58261 (10 mg kg−1 i.p.) in forced swim test whereas it left unaltered its stimulant motor effects. In conclusion, these data support the hypothesis that A2A receptor antagonists prolong escape

  6. Accelerated experience-dependent pruning of cortical synapses in ephrin-A2 knockout mice.

    PubMed

    Yu, Xinzhu; Wang, Gordon; Gilmore, Anthony; Yee, Ada Xin; Li, Xiang; Xu, Tonghui; Smith, Stephen J; Chen, Lu; Zuo, Yi

    2013-10-02

    Refinement of mammalian neural circuits involves substantial experience-dependent synapse elimination. Using in vivo two-photon imaging, we found that experience-dependent elimination of postsynaptic dendritic spines in the cortex was accelerated in ephrin-A2 knockout (KO) mice, resulting in fewer adolescent spines integrated into adult circuits. Such increased spine removal in ephrin-A2 KOs depended on activation of glutamate receptors, as blockade of the N-methyl-D-aspartate (NMDA) receptors eliminated the difference in spine loss between wild-type and KO mice. We also showed that ephrin-A2 in the cortex colocalized with glial glutamate transporters, which were significantly downregulated in ephrin-A2 KOs. Consistently, glial glutamate transport was reduced in ephrin-A2 KOs, resulting in an accumulation of synaptic glutamate. Finally, inhibition of glial glutamate uptake promoted spine elimination in wild-type mice, resembling the phenotype of ephrin-A2 KOs. Together, our results suggest that ephrin-A2 regulates experience-dependent, NMDA receptor-mediated synaptic pruning through glial glutamate transport during maturation of the mouse cortex. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Abnormal strategies during visual discrimination reversal learning in ephrin-A2(-/-) mice.

    PubMed

    Arnall, S; Cheam, L Y; Smart, C; Rengel, A; Fitzgerald, M; Thivierge, J P; Rodger, J

    2010-05-01

    Eph receptors and ephrins are involved in establishing topographic connectivity in primary sensory brain regions, but also in higher order structures including the cortex and hippocampus. Ephrin-A2(-/-) mice have abnormal topography in the primary visual system but have normal visual and learning performance on a simple visual discrimination task. Here we use signal detection theory to analyse learning behaviour of these mice. Wild-type (WT) and ephrin-A2(-/-) (KO) mice performed equally well in a two-stimulus visual discrimination task, with similar learning rates and response latencies. However, during reversal learning, when the rewarded stimulus was switched, the two genotypes exhibited differences in response strategies: while WTs favoured a win-stay strategy, KOs remained relatively neutral. KOs also exhibited a stronger lateralization bias in the initial stages of learning, choosing the same arm of the maze with high probability. In addition, use of a Bayesian "optimal observer" revealed that compared to WT, KO mice adapted their decisions less rapidly to a change in stimulus-reward relationship. We suggest that the misexpression of ephrin-A2 may lead to abnormal connectivity in regions known for their involvement in reversal learning and perseverative behaviours, including thalamic-prefrontal cortical-striatal circuitry and particularly orbitofrontal cortex. The implication is that topographic organisation of higher order brain regions may play an important role in learning and decision making.

  8. Impaired tumor microenvironment in EphA2-deficient mice inhibits tumor angiogenesis and metastatic progression.

    PubMed

    Brantley-Sieders, Dana M; Fang, Wei Bin; Hicks, Donna J; Zhuang, Guanglei; Shyr, Yu; Chen, Jin

    2005-11-01

    EphA2 belongs to a unique family of receptor tyrosine kinases that play critical roles in development and disease. Since EphA2 is required for ephrin-A1 ligand-induced vascular remodeling and is overexpressed in a variety of vascularized human adenocarcinomas, we assessed tumor angiogenesis and metastatic progression in EphA2-deficient host animals. 4T1 metastatic mammary adenocarcinoma cells transplanted subcutaneously and orthotopically into EphA2-deficient female mice displayed decreased tumor volume, tumor cell survival, microvascular density, and lung metastasis relative to tumor-bearing littermate controls. To determine if the phenotype in EphA2-deficient mice was endothelial cell intrinsic, we also analyzed endothelial cells isolated from EphA2-deficient animals for their ability to incorporate into tumor vessels in vivo, as well as to migrate in response to tumor-derived signals in vitro. EphA2-deficient endothelial cells displayed impaired survival and failed to incorporate into tumor microvessels in vivo, and displayed impaired tumor-mediated migration in vitro relative to controls. These data suggest that host EphA2 receptor tyrosine kinase function is required in the tumor microenvironment for tumor angiogenesis and metastatic progression.

  9. Group III secreted phospholipase A2 regulates epididymal sperm maturation and fertility in mice

    PubMed Central

    Sato, Hiroyasu; Taketomi, Yoshitaka; Isogai, Yuki; Miki, Yoshimi; Yamamoto, Kei; Masuda, Seiko; Hosono, Tomohiko; Arata, Satoru; Ishikawa, Yukio; Ishii, Toshiharu; Kobayashi, Tetsuyuki; Nakanishi, Hiroki; Ikeda, Kazutaka; Taguchi, Ryo; Hara, Shuntaro; Kudo, Ichiro; Murakami, Makoto

    2010-01-01

    Although lipid metabolism is thought to be important for the proper maturation and function of spermatozoa, the molecular mechanisms that underlie this dynamic process in the gonads remains incompletely understood. Here, we show that group III phospholipase A2 (sPLA2-III), a member of the secreted phospholipase A2 (sPLA2) family, is expressed in the mouse proximal epididymal epithelium and that targeted disruption of the gene encoding this protein (Pla2g3) leads to defects in sperm maturation and fertility. Although testicular spermatogenesis in Pla2g3–/– mice was grossly normal, spermatozoa isolated from the cauda epididymidis displayed hypomotility, and their ability to fertilize intact eggs was markedly impaired. Transmission EM further revealed that epididymal spermatozoa in Pla2g3–/– mice had both flagella with abnormal axonemes and aberrant acrosomal structures. During epididymal transit, phosphatidylcholine in the membrane of Pla2g3+/+ sperm underwent a dramatic shift in its acyl groups from oleic, linoleic, and arachidonic acids to docosapentaenoic and docosahexaenoic acids, whereas this membrane lipid remodeling event was compromised in sperm from Pla2g3–/– mice. Moreover, the gonads of Pla2g3–/– mice contained less 12/15-lipoxygenase metabolites than did those of Pla2g3+/+ mice. Together, our results reveal a role for the atypical sPLA2 family member sPLA2-III in epididymal lipid homeostasis and indicate that its perturbation may lead to sperm dysfunction. PMID:20424323

  10. Links Between Insulin Resistance, Adenosine A2B Receptors, and Inflammatory Markers in Mice and Humans

    PubMed Central

    Figler, Robert A.; Wang, Guoquan; Srinivasan, Susseela; Jung, Dae Young; Zhang, Zhiyou; Pankow, James S.; Ravid, Katya; Fredholm, Bertil; Hedrick, Catherine C.; Rich, Stephen S.; Kim, Jason K.; LaNoue, Kathryn F.; Linden, Joel

    2011-01-01

    OBJECTIVE To determine the mechanisms by which blockade of adenosine A2B receptors (A2BRs) reduces insulin resistance. RESEARCH DESIGN AND METHODS We investigated the effects of deleting or blocking the A2BR on insulin sensitivity using glucose tolerance tests (GTTs) and hyperinsulinemic-euglycemic clamps in mouse models of type 2 diabetes. The effects of diabetes on A2BR transcription and signaling were measured in human and mouse macrophages and mouse endothelial cells. In addition, tag single nucleotide polymorphisms (SNPs) in ∼42 kb encompassing the A2BR gene, ADORA2B, were evaluated for associations with markers of diabetes and inflammation. RESULTS Treatment of mice with the nonselective adenosine receptor agonist 5′-N-ethylcarboxamidoadensoine (NECA) increased fasting blood glucose and slowed glucose disposal during GTTs. These responses were inhibited by A2BR deletion or blockade and minimally affected by deletion of A1Rs or A2ARs. During hyperinsulinemic-euglycemic clamp of diabetic KKAY mice, A2BR antagonism increased glucose infusion rate, reduced hepatic glucose production, and increased glucose uptake into skeletal muscle and brown adipose tissue. Diabetes caused a four- to sixfold increase in A2BR mRNA in endothelial cells and macrophages and resulted in enhanced interleukin (IL)-6 production in response to NECA due to activation of protein kinases A and C. Five consecutive tag SNPs in ADORA2B were highly correlated with IL-6 and C-reactive protein (CRP). Diabetes had a highly significant independent effect on variation in inflammatory markers. The strength of associations between several ADORA2B SNPs and inflammatory markers was increased when accounting for diabetes status. CONCLUSIONS Diabetes affects the production of adenosine and the expression of A2BRs that stimulate IL-6 and CRP production, insulin resistance, and the association between ADORA2B SNPs and inflammatory markers. We hypothesize that increased A2BR signaling in diabetes

  11. Secretoglobin Superfamily Protein SCGB3A2 Alleviates House Dust Mite-Induced Allergic Airway Inflammation in Mice.

    PubMed

    Yoneda, Mitsuhiro; Xu, Lei; Kajiyama, Hiroaki; Kawabe, Shuko; Paiz, Jorge; Ward, Jerrold M; Kimura, Shioko

    2016-01-01

    Secretoglobin (SCGB) 3A2, a novel, lung-enriched, cytokine-like, secreted protein of small molecular weight, was demonstrated to exhibit various biological functions including anti-inflammatory, antifibrotic and growth-factor activities. Anti-inflammatory activity was uncovered using the ovalbumin-induced allergic airway inflammation model. However, further validation of this activity using knockout mice in a different allergic inflammation model is necessary in order to establish the antiallergic inflammatory role for this protein. Scgb3a2-null (Scgb3a2-/-) mice were subjected to nasal inhalation of Dermatophagoides pteronyssinus extract for 5 days/week for 5 consecutive weeks; control mice received nasal inhalation of saline as a comparator. Airway inflammation was assessed by histological analysis, the number of inflammatory cells and various Th2-type cytokine levels in the lungs and bronchoalveolar lavage fluids by qRT-PCR and ELISA, respectively. Exacerbated inflammation was found in the airway of Scgb3a2-/- mice subjected to house dust mite (HDM)-induced allergic airway inflammation compared with saline-treated control groups. All the inflammation end points were increased in the Scgb3a2-/- mice. The Ccr4 and Ccl17 mRNA levels were higher in HDM-treated lungs of Scgb3a2-/- mice than wild-type mice or saline-treated Scgb3a2-/- mice, whereas no changes were observed for Ccr3 and Ccl11 mRNA levels. These results demonstrate that SCGB3A2 has an anti-inflammatory activity in the HDM-induced allergic airway inflammation model, in which SCGB3A2 may modulate the CCR4-CCL17 pathway. SCGB3A2 may provide a useful tool to treat allergic airway inflammation, and further studies on the levels and function of SCGB3A2 in asthmatic patients are warranted. © 2016 S. Karger AG, Basel.

  12. 2,3,7, 8-TETRACHLORODIBENZO-P-DIOXIN (TCDD)-MEDIATED OXIDATIVE STRESS IN FEMALE CYP1A-2 KNOCKOUT (CYP1A2-/-) MICE

    EPA Science Inventory

    2,3,7,8-Tetrachlordibenzo-p-dioxin (TCDD)-Mediated Oxidative Stress in Female CYP1A2 Knockout (CYP1A2-/-) Mice

    Deborah Burgin1, Janet Diliberto2, Linda Birnbaum2
    1UNC Toxicology; 2USEPA/ORD/NHEERL, RTP, NC

    Most of the effects due to TCDD exposure are mediated via...

  13. Adenosine A(2A) receptors are necessary and sufficient to trigger memory impairment in adult mice.

    PubMed

    Pagnussat, N; Almeida, A S; Marques, D M; Nunes, F; Chenet, G C; Botton, P H S; Mioranzza, S; Loss, C M; Cunha, R A; Porciúncula, L O

    2015-08-01

    Caffeine (a non-selective adenosine receptor antagonist) prevents memory deficits in aging and Alzheimer's disease, an effect mimicked by adenosine A2 A receptor, but not A1 receptor, antagonists. Hence, we investigated the effects of adenosine receptor agonists and antagonists on memory performance and scopolamine-induced memory impairment in mice. We determined whether A2 A receptors are necessary for the emergence of memory impairments induced by scopolamine and whether A2 A receptor activation triggers memory deficits in naïve mice, using three tests to assess short-term memory, namely the object recognition task, inhibitory avoidance and modified Y-maze. Scopolamine (1.0 mg·kg(-1) , i.p.) impaired short-term memory performance in all three tests and this scopolamine-induced amnesia was prevented by the A2 A receptor antagonist (SCH 58261, 0.1-1.0 mg·kg(-1) , i.p.) and by the A1 receptor antagonist (DPCPX, 0.2-5.0 mg·kg(-1) , i.p.), except in the modified Y-maze where only SCH58261 was effective. Both antagonists were devoid of effects on memory or locomotion in naïve rats. Notably, the activation of A2 A receptors with CGS 21680 (0.1-0.5 mg·kg(-1) , i.p.) before the training session was sufficient to trigger memory impairment in the three tests in naïve mice, and this effect was prevented by SCH 58261 (1.0 mg·kg(-1) , i.p.). Furthermore, i.c.v. administration of CGS 21680 (50 nmol) also impaired recognition memory in the object recognition task. These results show that A2 A receptors are necessary and sufficient to trigger memory impairment and further suggest that A1 receptors might also be selectively engaged to control the cholinergic-driven memory impairment. © 2015 The British Pharmacological Society.

  14. Adenosine A2A receptors are necessary and sufficient to trigger memory impairment in adult mice

    PubMed Central

    Pagnussat, N; Almeida, A S; Marques, D M; Nunes, F; Chenet, G C; Botton, P H S; Mioranzza, S; Loss, C M; Cunha, R A; Porciúncula, L O

    2015-01-01

    Background and Purpose Caffeine (a non-selective adenosine receptor antagonist) prevents memory deficits in aging and Alzheimer’s disease, an effect mimicked by adenosine A2A receptor, but not A1 receptor, antagonists. Hence, we investigated the effects of adenosine receptor agonists and antagonists on memory performance and scopolamine-induced memory impairment in mice. Experimental Approach We determined whether A2A receptors are necessary for the emergence of memory impairments induced by scopolamine and whether A2A receptor activation triggers memory deficits in naïve mice, using three tests to assess short-term memory, namely the object recognition task, inhibitory avoidance and modified Y-maze. Key Results Scopolamine (1.0 mg·kg−1, i.p.) impaired short-term memory performance in all three tests and this scopolamine-induced amnesia was prevented by the A2A receptor antagonist (SCH 58261, 0.1–1.0 mg·kg−1, i.p.) and by the A1 receptor antagonist (DPCPX, 0.2–5.0 mg·kg−1, i.p.), except in the modified Y-maze where only SCH58261 was effective. Both antagonists were devoid of effects on memory or locomotion in naïve rats. Notably, the activation of A2A receptors with CGS 21680 (0.1–0.5 mg·kg−1, i.p.) before the training session was sufficient to trigger memory impairment in the three tests in naïve mice, and this effect was prevented by SCH 58261 (1.0 mg·kg−1, i.p.). Furthermore, i.c.v. administration of CGS 21680 (50 nmol) also impaired recognition memory in the object recognition task. Conclusions and Implications These results show that A2A receptors are necessary and sufficient to trigger memory impairment and further suggest that A1 receptors might also be selectively engaged to control the cholinergic-driven memory impairment. PMID:25939452

  15. GH Receptor Deficiency in Ecuadorian Adults Is Associated With Obesity and Enhanced Insulin Sensitivity.

    PubMed

    Guevara-Aguirre, Jaime; Rosenbloom, Arlan L; Balasubramanian, Priya; Teran, Enrique; Guevara-Aguirre, Marco; Guevara, Carolina; Procel, Patricio; Alfaras, Irene; De Cabo, Rafael; Di Biase, Stefano; Narvaez, Luis; Saavedra, Jannette; Longo, Valter D

    2015-07-01

    Ecuadorian subjects with GH receptor deficiency (GHRD) have not developed diabetes, despite obesity. We sought to determine the metabolic associations for this phenomenon. Four studies were carried out: 1) glucose, lipid, adipocytokine concentrations; 2) metabolomics evaluation; 3) metabolic responses to a high-calorie meal; and 4) oral glucose tolerance tests. Clinical Research Institute in Quito, Ecuador. Adults homozygous for the E180 splice mutation of the GH receptor (GHRD) were matched for age, gender, and body mass index with unaffected control relatives (C) as follows: study 1, 27 GHRD and 35 C; study 2, 10 GHRD and 10 C; study 3, seven GHRD and 11 C; and study 4, seven GHRD and seven C. Although GHRD subjects had greater mean percentage body fat than controls, their fasting insulin, 2-hour blood glucose, and triglyceride levels were lower. The indicator of insulin sensitivity, homeostasis model of assessment 2%S, was greater (P < .0001), and the indicator of insulin resistance, homeostasis model of assessment 2-IR, was lower (P = .0025). Metabolomic differences between GHRD and control subjects were consistent with their differing insulin sensitivity, including postprandial decreases of branched-chain amino acids that were more pronounced in controls. High molecular weight and total adiponectin concentrations were greater in GHRD (P = .0004 and P = .0128, respectively), and leptin levels were lower (P = .02). Although approximately 65% the weight of controls, GHRD subjects consumed an identical high-calorie meal; nonetheless, their mean glucose concentrations were lower, with mean insulin levels one-third those of controls. Results of the 2-hour oral glucose tolerance test were similar. Measures of insulin sensitivity, adipocytokines, and energy metabolites. Without GH counter-regulation, GHRD is associated with insulin efficiency and obesity. Lower leptin levels, despite higher percentage body fat, suggest that obesity-associated leptin resistance is GH

  16. Adenosine A2A Receptor Deletion Blocks the Beneficial Effects of Lactobacillus reuteri in Regulatory T-Deficient Scurfy Mice

    PubMed Central

    He, Baokun; Hoang, Thomas K.; Tran, Dat Q.; Rhoads, Jon Marc; Liu, Yuying

    2017-01-01

    The lack of a functional Foxp3 transcription factor and regulatory T (Treg) cells causes lethal, CD4+ T cell-driven autoimmune diseases in scurfy (SF) mice and humans. Recent studies have shown that adenosine A2A receptor activation limits inflammation and tissue damage, thereby playing an anti-inflammatory role. However, the role of the adenosine A2A receptor in the development of disease in SF mice remains unclear. Using a genetic approach, we found that adenosine A2A receptor deletion in SF mice (SF⋅A2A-/-) does not affect early life events, the development of a lymphoproliferative disorder, or hyper-production of pro-inflammatory cytokines seen in the Treg-deficiency state. As shown previously, Lactobacillus reuteri DSM 17938 treatment prolonged survival and reduced multiorgan inflammation in SF mice. In marked contrast, A2A receptor deletion completely blocked these beneficial effects of L. reuteri in SF mice. Altogether, these results suggest that although absence of the adenosine A2A receptor does not affect the development of disease in SF mice, it plays a critical role in the immunomodulation by L. reuteri in Treg-deficiency disease. The adenosine A2A receptor and its activation may have a role in treating other Treg dysfunction-mediated autoimmune diseases. PMID:29270168

  17. Involvement of thromboxane A2 in interleukin-31-induced itch-associated response in mice.

    PubMed

    Andoh, Tsugunobu; Li, Sikai; Uta, Daisuke

    2018-04-01

    Atopic dermatitis is a chronic and severe pruritic skin disease. Interlukin-31 (IL-31) has been recently demonstrated to be one of the key pruritogens in atopic dermatitis. However, the mechanisms underlying IL-31-induced itching remains unclear. In our previous study, we have shown that thromboxane (TX) A 2 is involved in itch-associated responses in mice with atopy-like skin diseases. IL-31 was given intradermally into the rostral back of ICR mice and the hind-paw scratching to the injection site were counted. Expression of TX synthase and IL-31 receptors were analyzed using immunohistochemical staining or RT-PCR in mouse skin or primary cultures of mouse keratinocytes. The concentration of TXB 2 , a metabolite of TXA 2 , in the skin and the culture medium of primary cultures of mouse keratinocytes was measured using enzyme immunoassay. The concentration of intracellular Ca 2+ ions in mouse keratinocytes was measured using the calcium imaging method. An intradermal injection of IL-31 elicited scratching, an itch-related response, in mice. The scratching was inhibited by TP TXA 2 receptor antagonist DCHCH. The distribution of TX synthase and IL-31RA receptor was mainly epidermal keratinocytes in the skin. The primary cultures of keratinocytes expressed the mRNAs of TX synthase and IL-31 receptors. IL-31 increased the concentration of TXB 2 , which was inhibited by TX synthase inhibitor sodium ozagrel and EGTA, in the skin and the culture medium of primary cultures of keratinocytes. IL-31 increased the concentration of intracellular Ca 2+ ions in mouse keratinocytes. It is suggested that IL-31 elicits itch-associated responses through TXA 2 produced from keratinocytes. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  18. Secretoglobin 3A2 Exhibits Anti-Fibrotic Activity in Bleomycin-Induced Pulmonary Fibrosis Model Mice.

    PubMed

    Cai, Yan; Kimura, Shioko

    2015-01-01

    Secretoglobin (SCGB) 3A2 is a novel lung-enriched cytokine, previously shown to exhibit anti-inflammatory, growth factor, and anti-fibrotic activities. The latter activity was demonstrated using exogenously-administered recombinant SCGB3A2 in the bleomycin (BLM)-induced pulmonary fibrosis model. Whether SCGB3A2 exhibits anti-fibrotic activity in vivo is not known. Mice null for the Scgb3a2 gene were subjected to the BLM-induced pulmonary fibrosis model, and the severity of pulmonary fibrosis determined using histological and biochemical methods. BLM treatment caused weight loss of both Scgb3a2-null and wild-type mice, however, the loss was far more pronounced in BLM-treated Scgb3a2-null than wild-type mice, and the weight of day 21 of BLM-treated Scgb3a2-null mice was about half of that of BLM-treated wild-type mice. Hematoxylin & Eosin, Masson Trichrome, and Sirius Red staining of lung sections, Ashcroft fibrosis scores, hydroxyproline contents, and the levels of mRNAs encoding various collagens demonstrated that BLM-treated Scgb3a2-null mouse lungs had more severe fibrosis than those of wild-type mouse lungs. Total and differential inflammatory cell numbers in bronchoalveolar lavage fluids, and levels of lung mRNAs including those encoding Th2 cytokines such as IL-4 and profibrotic cytokines such as TGFβ were higher in BLM-treated Scgb3a2-null mouse lungs as compared to those of wild-type mouse lungs. In contrast, mRNAs encoding surfactant proteins A, B, C, and D, and SCGB1A1 did not differ between BLM-treated Scgb3a2-null and wild-type mouse lungs. The role of SCGB3A2 in fibrosis was revisited using Scgb3a2-null mice and littermate controls in the BLM-induced pulmonary fibrosis model. The pulmonary fibrosis in the Scgb3a2-null mice was more severe than the wild-type controls, thus establishing that SCGB3A2 has anti-fibrotic activity in vivo. Importantly, surfactant proteins and SCGB1A1 appear not to be involved in the susceptibility of Scgb3a2-null mice to BLM

  19. Genetic Deletion of the Adenosine A2A Receptor Confers Postnatal Development of Relative Myopia in Mice

    PubMed Central

    Zhou, Xiangtian; Huang, Qinzhu; An, Jianhong; Lu, Runxia; Qin, Xiaoyi; Jiang, Liqin; Li, Yuan; Wang, Jianhua; Chen, Jiangfan; Qu, Jia

    2010-01-01

    Purpose. To critically evaluate whether the adenosine A2A receptor (A2AR) plays a role in postnatal refractive development in mice. Methods. Custom-built biometric systems specifically designed for mice were used to assess the development of relative myopia by examining refraction and biometrics in A2AR knockout (KO) mice and wild-type (WT) littermates between postnatal days (P)28 and P56. Ocular dimensions were measured by customized optical coherence tomography (OCT), refractive state by eccentric infrared photorefraction (EIR), and corneal radius of curvature by modified keratometry. Scleral collagen diameter and density were examined by electron microscopy on P35. The effect of A2AR activation on collagen mRNA expression and on soluble collagen production was examined in cultured human scleral fibroblasts by real-time RT-PCR and a collagen assay kit. Results. Compared with WT littermates, the A2AR KO mice displayed relative myopia (average difference, 5.1 D between P28 and P35) and associated increases in VC depth and axial length from P28 to P56. Furthermore, the myopic shift in A2AR KO mice was associated with ultrastructural changes in the sclera: Electron microscopy revealed denser collagen fibrils with reduced diameter in A2AR KO compared with WT. Last, A2AR activation induced expression of mRNAs for collagens I, III, and V and increased production of soluble collagen in cultured human scleral fibroblasts. Conclusions. Genetic deletion of the A2AR promotes development of relative myopia with increased axial length and altered scleral collagen fiber structure during postnatal development in mice. Thus, the A2AR may be important in normal refractive development. PMID:20484596

  20. Adenosine receptor A2A deficiency in leukocytes increases arterial neointima formation in apolipoprotein E-deficient mice.

    PubMed

    Wang, Huan; Zhang, Weiyu; Tang, Rong; Zhu, Chuhong; Bucher, Christoph; Blazar, Bruce R; Geng, Jian-Guo; Zhang, Chunxiang; Linden, Joel; Wu, Chaodong; Huo, Yuqing

    2010-05-01

    To use the mice deficient in both adenosine receptor A(2A)(A(2A)R(-/-)) and apolipoprotein E (apoE(-/-)) to investigate the role of A(2A)R in mediating the interactions of leukocytes with injured arterial walls and the formation of arterial neointima induced by a guide wire. In apoE(-/-) mice, A(2A)R deficiency increased the size of the arterial neointima in injured carotid arteries by 83%. Arterial neointima formation was also enhanced in chimeric mice that underwent bone marrow transplantation (these mice lacked A(2A)R in their bone marrow-derived cells). Epifluorescence intravital microscopy showed that neutrophil rolling and adherence to the injured arterial area were enhanced by 80% and 110% in A(2A)R(-/-)/apoE(-/-) mice, respectively. This phenomenon occurred even though the protein levels of homing molecules on A(2A)R-deficient neutrophils were unchanged from those of wild-type neutrophils. A(2A)R-deficient neutrophils exhibited an increase in the phosphorylation of p38 mitogen-activated protein kinase, P-selectin glycoprotein ligand-1 (PSGL-1) clustering, and the affinity of b(2) integrins. The inhibition of p38 phosphorylation abrogated the increased PSGL-1 clustering and beta(2) integrin affinity, thus reversing the increased homing ability of A(2A)R-deficient leukocytes. A(2A)R plays a complex role in inflammation and tissue injury. The deficiency of A(2A)R enhances the homing ability of leukocytes and increases the formation of the arterial neointima after injury. A(2A)R antagonists are being tested for the treatment of neurodegenerative and other chronic diseases. An evaluation of the effect of A(2A)R antagonists on arterial restenosis after arterial angioplasty should be conducted.

  1. Absence of the Adenosine A2A Receptor Confers Pulmonary Arterial Hypertension and Increased Pulmonary Vascular Remodeling in Mice

    PubMed Central

    Xu, M.H.; Gong, Y.S.; Su, M.S.; Dai, Z.Y.; Dai, S.S.; Bao, S.Z.; Li, N.; Zheng, R.Y.; He, J.C.; Chen, J.F.; Wang, X.T.

    2011-01-01

    Background Pulmonary arterial hypertension (PAH) is characterized by sustained elevation of pulmonary vascular resistance resulting from endothelial and smooth muscle cell dysfunction and collagen deposition in pulmonary vascular walls. In this study, we investigated the role of the adenosine A2A receptor (A2AR) in the development of PAH by determining the effect of genetic inactivation of A2ARs on pulmonary vascular remodeling in mice. Methods and Results We characterized hemodynamic, histological and ultrastructural changes in pulmonary vascular remodeling in A2AR knockout (KO) mice compared with their wild-type (WT) littermates after exposure to normoxia and hypoxic conditions. After exposure to normoxia, compared to WT mice, A2AR KO mice displayed: (1) increased right ventricular systolic pressures and an elevated ratio of the right ventricle over left ventricle plus septum (Fulton index), (2) increased wall area and thickness as well as enhanced smooth muscle actin immunoreactivity in pulmonary resistance vessels, (3) increased proliferating cell nuclear antigen-positive cells in pulmonary resistance vessels and (4) increased smooth muscle cells hypertrophy and collagen deposition in the adventitia of pulmonary arteriole walls as revealed by electron microscope. By contrast, histological analysis revealed no features of hypertensive nephropathy in A2AR KO mice and there was no significant difference in systemic blood pressure, and left ventricular masses among the 3 genotypes. Furthermore, following chronic exposure to hypoxia, A2AR KO mice exhibited exacerbated elevation in right ventricular systolic pressure, hypertrophy of pulmonary resistance vessels and increased cell proliferation in pulmonary resistance vessels, compared to WT littermates. Thus, genetic inactivation of A2ARs selectively produced PAH and associated increased smooth muscle proliferation and collagen deposition. Conclusions Extracellular adenosine acting at A2ARs represents an important

  2. Adenosine A2A receptor deletion affects social behaviors and anxiety in mice: Involvement of anterior cingulate cortex and amygdala.

    PubMed

    López-Cruz, Laura; Carbó-Gas, Maria; Pardo, Marta; Bayarri, Pilar; Valverde, Olga; Ledent, Catherine; Salamone, John D; Correa, Mercè

    2017-03-15

    Blockade of adenosine A 2A receptors can potentiate motivation to work for natural reinforcers such as food. Conspecific interaction is a potent natural reinforcer in social animals that can be manifested as preference for social exploration versus other sources of novel stimulation. Deficiencies in this type of motivated behavior (social withdrawal) have been seen in several pathologies such as autism and depression. However, the role of A 2A receptors in motivation for social interaction has not been widely explored. Social interaction paradigms evaluate the natural preference of animals for exploring other conspecifics, and the ability to differentiate between familiar versus novel ones. Anxiety is one of the factors that can induce avoidance of social interaction. In the present study, adenosine A 2A knockout (A 2A KO) and wild-type (WT) mice were assessed for social and anxiety-related behaviors. c-Fos immunoreactivity was evaluated as a measure of neuronal activation in brain areas involved in different aspects of motivation and emotional processes. Although A 2A KO mice showed an anxious profile, they displayed higher levels of sociability and were less sensitive to social novelty. WT mice displayed a typical pattern of social recognition 24h later, but not A 2A KO mice, which explored equally both conspecifics. There were no differences between strains in aggressiveness, perseverance or social odor preferences. c-Fos immunoreactivity in A 2A KO mice was higher in anterior cingulate and amygdala compared to WT mice. Thus, A 2A receptors appear to be potential targets for the improvement of pathologies related to social function. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. AhrdCyp1a2(−/−) mice show increased susceptibility to PCB-induced developmental neurotoxicity

    PubMed Central

    Curran, Christine Perdan; Altenhofen, Emily; Ashworth, Amy; Brown, Austin; Kamau-Cheggeh, Cellestine; Curran, Melinda; Evans, Amber; Floyd, Rikki; Fowler, Jocelyn; Garber, Helen; Hays, Breann; Kraemer, Sarah; Lang, Anna; Mynhier, Andrea; Samuels, Ashton; Strohmaier, Carly

    2012-01-01

    Polychlorinated biphenyls (PCBs) are developmental neurotoxicants that produce cognitive and behavioral changes in children exposed during gestation and lactation. Coplanar PCBs bind the aryl hydrocarbon receptor (AHR) and can be sequestered in liver by cytochrome P450 1A2 (CYP1A2). The AHR is a ligand-activated transcription factor which increases expression of the CYP1 family, including CYP1A2. Our previous work examining genetic susceptibility to developmental PCB neurotoxicity showed that AhrbCyp1a2(−/−) mice with the high-affinity Ahrb allele and lacking CYP1A2 were most susceptible while AhrbCyp1a2(+/+) and poor-affinity AhrdCyp1a2(+/+) mice were resistant. To follow up, a fourth line of mice was generated with the AhrdCyp1a2(−/−) genotype and compared with the background strain AhrbCyp1a2(+/+). Dams received a PCB mixture or the corn oil vehicle at gestational day 10 (GD10) and postnatal day 5 (PND5). Offspring were tested at PND60 in open field locomotor, acoustic startle with pre-pulse inhibition (PPI), novel object recognition and Morris water maze. Locomotor activity was increased in PCB-treated AhrbCyp1a2(+/+) mice, but no differences were seen in control v. PCB-treated AhrdCyp1a2(−/−) mice. PCB-treated AhrdCyp1a2(−/−) mice had a higher baseline startle response and significantly reduced pre-pulse inhibition at the 74dB level compared with corn oil-treated controls (P<0.05). PCB-treated AhrdCyp1a2(−/−) mice had impairments in novel objective recognition (P<0.05) and during all three hidden platform phases of Morris water maze (P<0.01). Combined with our previous findings, these results indicate Cyp1a2 genotype is more important in susceptibility to PCB-induced deficits in learning and memory, but Ahr genotype appears more important when assessing acoustic startle-PPI and locomotor activity. PMID:22935098

  4. Differences in the alveolar macrophage proteome in transgenic mice expressing human SP-A1 and SP-A2

    PubMed Central

    Phelps, David S.; Umstead, Todd M.; Silveyra, Patricia; Hu, Sanmei; Wang, Guirong; Floros, Joanna

    2014-01-01

    Surfactant protein A (SP-A) plays a number of roles in lung host defense and innate immunity. There are two human genes, SFTPA1 and SFTPA2, and evidence indicates that the function of SP-A1 and SP-A2 proteins differ in several respects. To investigate the impact of SP-A1 and SP-A2 on the alveolar macrophage (AM) phenotype, we generated humanized transgenic (hTG) mice on the SP-A knockout (KO) background, each expressing human SP-A1 or SP-A2. Using two-dimensional difference gel electrophoresis (2D-DIGE) we studied the AM cellular proteome. We compared mouse lines expressing high levels of SPA1, high levels of SP-A2, low levels of SP-A1, and low levels of SP-A2, with wild type (WT) and SP-A KO mice. AM from mice expressing high levels of SP-A2 were the most similar to WT mice, particularly for proteins related to actin and the cytoskeleton, as well as proteins regulated by Nrf2. The expression patterns from mouse lines expressing higher levels of the transgenes were almost the inverse of one another – the most highly expressed proteins in SP-A2 exhibited the lowest levels in the SP-A1 mice and vice versa. The mouse lines where each expressed low levels of SP-A1 or SP-A2 transgene had very similar protein expression patterns suggesting that responses to low levels of SP-A are independent of SP-A genotype, whereas the responses to higher amounts of SP-A are genotype-dependent. Together these observations indicate that in vivo exposure to SP-A1 or SP-A2 differentially affects the proteomic expression of AMs, with SP-A2 being more similar to WT. PMID:24729982

  5. Differences in adenosine A-1 and A-2 receptor density revealed by autoradiography in methylxanthine-sensitive and insensitive mice

    SciTech Connect

    Jarvis, M.F.; Williams, M.

    1988-07-01

    Two strains of inbred mice, CBA/J and SWR/J, have been identified which are, respectively, sensitive and insensitive to the behavioral and toxic effects of methylxanthines. Autoradiographic analyses of brain adenosine receptors were conducted with (/sup 3/H)CHA to label adenosine A-1 receptors and (/sup 3/H)NECA, in the presence of 50 nM CPA, to label adenosine A-2 receptors. For both mouse strains, adenosine A-1 receptors were most highly concentrated in the hippocampus and cerebellum whereas adenosine A-2 receptors were selectively localized in the striatum. CBA/J mice displayed a 30% greater density of adenosine A-1 receptors in the hippocampal CA-1 and CA-3 regionsmore » and in the cerebellum as compared to the SWR/J mice. The number of A-2 receptors (Bmax) was 40% greater in the striatum and olfactory tubercle of CBA/J as compared to SWR/J mice. No significant regional differences in A-1 or A-2 receptor affinities were observed between these inbred strains of mice. These results indicate that the differential sensitivity to methylxanthines between these mouse strains may reflect a genetically mediated difference in regional adenosine receptor densities.« less

  6. Disruption of Cytochrome P4501A2 in mice leads to increased susceptibility to hyperoxic lung injury

    PubMed Central

    Wang, Lihua; Lingappan, Krithika; Jiang, Weiwu; Couroucli, Xanthi I.; Welty, Stephen E.; Shivanna, Binoy; Barrios, Roberto; Wang, Gangduo; Khan, M. Firoze; Gonzalez, Frank J.; Roberts, L Jackson; Moorthy, Bhagavatula

    2015-01-01

    Hyperoxia contributes to acute lung injury (ALI) in diseases such as acute respiratory distress syndrome (ARDS). Cytochrome P450 (CYP)1A enzymes have been implicated in hyperoxic lung injury, but the mechanistic role(s) of CYP1A2 in pulmonary injury is not known. We hypothesized that mice lacking the gene for Cyp1a2 (which is predominantly expressed in the liver) will be more sensitive to lung injury and inflammation mediated by hyperoxia, and that CYP1A2 will play a protective role by attenuating lipid peroxidation and oxidative stress in the lung. Eight to ten week old WT (C57BL/6) or Cyp1a2(−/−) mice were exposed to hyperoxia (>95% O2) or maintained in room air for 24–72 h. Lung injury was assessed by determining the ratios of lung weight/body weight (LW/BW), and by histology. Extent of inflammation was determined by measuring the number of neutrophils in the lung as well as cytokine expression. The Cyp1a2(−/−) mice under hyperoxic conditions showed increased LW/BW ratios, lung injury, neutrophil infiltration, IL-6 and TNF-α levels, and augmented lipid peroxidation, as evidenced by increased formation of malondialdehyde (MDA)- and 4-hydroxynonenal (4-HNE)-protein adducts, and pulmonary isofurans compared to those of WT mice. In vitro experiments showed that the F2-isoprostane PGF2-α is metabolized by CYP1A2 to a dinor metabolite, providing evidence for a catalytic role for CYP1A2 in the metabolism of F2-isoprostanes. In summary, our results support the hypothesis that hepatic CYP1A2 plays a critical role in the attenuation against hyperoxic lung injury by decreasing lipid peroxidation and oxidative stress in vivo. PMID:25680282

  7. Changes in spinal delta and kappa opioid systems in mice deficient in the A2A receptor gene.

    PubMed

    Bailey, Alexis; Ledent, Catherine; Kelly, Mary; Hourani, Susanna M O; Kitchen, Ian

    2002-11-01

    A large body of evidence indicates important interactions between the adenosine and opioid systems in regulating pain at both the spinal and supraspinal level. Mice lacking the A(2A) receptor gene have been developed successfully, and these animals were shown to be hypoalgesic. To investigate whether there are any compensatory alterations in opioid systems in mutant animals, we have performed quantitative autoradiographic mapping of mu, delta, kappa, and opioid receptor-like (ORL1) opioid receptors in the brains and spinal cords of wild-type and homozygous A(2A) receptor knock-out mice. In addition, mu-, delta-, and kappa-mediated antinociception using the tail immersion test was tested in wild-type and homozygous A(2A) receptor knock-out mice. A significant reduction in [3H]deltorphin-I binding to delta receptors and a significant increase in [3H]CI-977 binding to kappa receptors was detected in the spinal cords but not in the brains of the knock-out mice. Mu and ORL1 receptor expression were not altered significantly. Moreover, a significant reduction in delta-mediated antinociception and a significant increase in kappa-mediated antinociception were detected in mutant mice, whereas mu-mediated antinociception was unaffected. Comparison of basal nociceptive latencies showed a significant hypoalgesia in knock-out mice when tested at 55 degrees C but not at 52 degrees C. The results suggest a functional interaction between the spinal delta and kappa opioid and the peripheral adenosine system in the control of pain pathways.

  8. β1-Adrenergic receptor deficiency in ghrelin-expressing cells causes hypoglycemia in susceptible individuals

    PubMed Central

    Mani, Bharath K.; Osborne-Lawrence, Sherri; Vijayaraghavan, Prasanna; Hepler, Chelsea; Zigman, Jeffrey M.

    2016-01-01

    Ghrelin is an orexigenic gastric peptide hormone secreted when caloric intake is limited. Ghrelin also regulates blood glucose, as emphasized by the hypoglycemia that is induced by caloric restriction in mouse models of deficient ghrelin signaling. Here, we hypothesized that activation of β1-adrenergic receptors (β1ARs) localized to ghrelin cells is required for caloric restriction–associated ghrelin release and the ensuing protective glucoregulatory response. In mice lacking the β1AR specifically in ghrelin-expressing cells, ghrelin secretion was markedly blunted, resulting in profound hypoglycemia and prevalent mortality upon severe caloric restriction. Replacement of ghrelin blocked the effects of caloric restriction in β1AR-deficient mice. We also determined that treating calorically restricted juvenile WT mice with beta blockers led to reduced plasma ghrelin and hypoglycemia, the latter of which is similar to the life-threatening, fasting-induced hypoglycemia observed in infants treated with beta blockers. These findings highlight the critical functions of ghrelin in preventing hypoglycemia and promoting survival during severe caloric restriction and the requirement for ghrelin cell–expressed β1ARs in these processes. Moreover, these results indicate a potential role for ghrelin in mediating beta blocker–associated hypoglycemia in susceptible individuals, such as young children. PMID:27548523

  9. β1-Adrenergic receptor deficiency in ghrelin-expressing cells causes hypoglycemia in susceptible individuals.

    PubMed

    Mani, Bharath K; Osborne-Lawrence, Sherri; Vijayaraghavan, Prasanna; Hepler, Chelsea; Zigman, Jeffrey M

    2016-09-01

    Ghrelin is an orexigenic gastric peptide hormone secreted when caloric intake is limited. Ghrelin also regulates blood glucose, as emphasized by the hypoglycemia that is induced by caloric restriction in mouse models of deficient ghrelin signaling. Here, we hypothesized that activation of β1-adrenergic receptors (β1ARs) localized to ghrelin cells is required for caloric restriction-associated ghrelin release and the ensuing protective glucoregulatory response. In mice lacking the β1AR specifically in ghrelin-expressing cells, ghrelin secretion was markedly blunted, resulting in profound hypoglycemia and prevalent mortality upon severe caloric restriction. Replacement of ghrelin blocked the effects of caloric restriction in β1AR-deficient mice. We also determined that treating calorically restricted juvenile WT mice with beta blockers led to reduced plasma ghrelin and hypoglycemia, the latter of which is similar to the life-threatening, fasting-induced hypoglycemia observed in infants treated with beta blockers. These findings highlight the critical functions of ghrelin in preventing hypoglycemia and promoting survival during severe caloric restriction and the requirement for ghrelin cell-expressed β1ARs in these processes. Moreover, these results indicate a potential role for ghrelin in mediating beta blocker-associated hypoglycemia in susceptible individuals, such as young children.

  10. Bee venom phospholipase A2 ameliorates motor dysfunction and modulates microglia activation in Parkinson's disease alpha-synuclein transgenic mice.

    PubMed

    Ye, Minsook; Chung, Hwan-Suck; Lee, Chanju; Hyun Song, Joo; Shim, Insop; Kim, Youn-Sub; Bae, Hyunsu

    2016-07-08

    α-Synuclein (α-Syn) has a critical role in microglia-mediated neuroinflammation, which leads to the development of Parkinson's disease (PD). Recent studies have shown that bee venom (BV) has beneficial effects on PD symptoms in human patients or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxin-induced PD mice. This study investigated whether treatment with BV-derived phospholipase A2 (bvPLA2) would improve the motor dysfunction and pathological features of PD in human A53T α-Syn mutant transgenic (A53T Tg) mice. The motor dysfunction of A53T Tg mice was assessed using the pole test. The levels of α-Syn, microglia and the M1/M2 phenotype in the spinal cord were evaluated by immunofluorescence. bvPLA2 treatment significantly ameliorated motor dysfunction in A53T Tg mice. In addition, bvPLA2 significantly reduced the expression of α-Syn, the activation and numbers of microglia, and the ratio of M1/M2 in A53T Tg mice. These results suggest that bvPLA2 could be a promising treatment option for PD.

  11. Bee venom phospholipase A2 ameliorates motor dysfunction and modulates microglia activation in Parkinson's disease alpha-synuclein transgenic mice

    PubMed Central

    Ye, Minsook; Chung, Hwan-Suck; Lee, Chanju; Hyun Song, Joo; Shim, Insop; Kim, Youn-Sub; Bae, Hyunsu

    2016-01-01

    α-Synuclein (α-Syn) has a critical role in microglia-mediated neuroinflammation, which leads to the development of Parkinson's disease (PD). Recent studies have shown that bee venom (BV) has beneficial effects on PD symptoms in human patients or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxin-induced PD mice. This study investigated whether treatment with BV-derived phospholipase A2 (bvPLA2) would improve the motor dysfunction and pathological features of PD in human A53T α-Syn mutant transgenic (A53T Tg) mice. The motor dysfunction of A53T Tg mice was assessed using the pole test. The levels of α-Syn, microglia and the M1/M2 phenotype in the spinal cord were evaluated by immunofluorescence. bvPLA2 treatment significantly ameliorated motor dysfunction in A53T Tg mice. In addition, bvPLA2 significantly reduced the expression of α-Syn, the activation and numbers of microglia, and the ratio of M1/M2 in A53T Tg mice. These results suggest that bvPLA2 could be a promising treatment option for PD. PMID:27388550

  12. Suppression of Hepatic Cyp1a2 by Total Ginsenosides in Lipopolysaccharide-Treated Mice and Primary Mouse Hepatocytes.

    PubMed

    Sun, Haiyan; Yan, Yijing; Xu, Chenshu; Wan, Hongxia; Liu, Dong

    2016-03-23

    The roots of Panax ginseng (ginseng) have been extensively used in traditional Chinese medicine. However, herb-drug interactions between ginseng and other co-administered drugs are not fully understood concerning the effect of ginseng on drug metabolism and clearance. The current study aimed to elucidate the effect of total ginsenosides, a typical ginseng extract, on the regulation of Cyp1a2, a key enzyme to regulate drug metabolism under the normal and inflammatory conditions in mice. Female C57BL/6J mice treated with vehicle and lipopolysaccharide (LPS) were intragastrically administered ginseng extract for 7 days before hepatic P450 expression was analyzed. Primary mouse hepatocytes were also employed to further explore the effects of total ginsenosides on Cyp1a2 expression. The results showed that total ginsenosides in P. ginseng extract exhibited a concentration-dependent suppression on Cyp1a2 mRNA and protein level in both mice and primary mouse hepatocytes. Notably, the inhibitory effects of total ginsenosides on Cyp1a2 mRNA and protein expression were further enhanced following LPS treatment. Therefore, future research is warranted to investigate the role of ginsenosides in the regulation of hepatic CYP450s. Moreover, consumption of ginseng as food or supplement should be monitored for patients on combinational therapy, especially those with inflammatory diseases.

  13. Early childhood BMI trajectories in monogenic obesity due to leptin, leptin receptor, and melanocortin 4 receptor deficiency.

    PubMed

    Kohlsdorf, Katja; Nunziata, Adriana; Funcke, Jan-Bernd; Brandt, Stephanie; von Schnurbein, Julia; Vollbach, Heike; Lennerz, Belinda; Fritsch, Maria; Greber-Platzer, Susanne; Fröhlich-Reiterer, Elke; Luedeke, Manuel; Borck, Guntram; Debatin, Klaus-Michael; Fischer-Posovszky, Pamela; Wabitsch, Martin

    2018-02-27

    To evaluate whether early childhood body mass index (BMI) is an appropriate indicator for monogenic obesity. A cohort of n = 21 children living in Germany or Austria with monogenic obesity due to congenital leptin deficiency (group LEP, n = 6), leptin receptor deficiency (group LEPR, n = 6) and primarily heterozygous MC4 receptor deficiency (group MC4R, n = 9) was analyzed. A control group (CTRL) was defined that consisted of n = 22 obese adolescents with no mutation in the above mentioned genes. Early childhood (0-5 years) BMI trajectories were compared between the groups at selected time points. The LEP and LEPR group showed a tremendous increase in BMI during the first 2 years of life with all patients displaying a BMI >27 kg/m 2 (27.2-38.4 kg/m 2 ) and %BMI P95 (percentage of the 95th percentile BMI for age and sex) >140% (144.8-198.6%) at the age of 2 years and a BMI > 33 kg/m 2 (33.3-45.9 kg/m 2 ) and %BMI P95  > 184% (184.1-212.6%) at the age of 5 years. The MC4R and CTRL groups had a later onset of obesity with significantly lower BMI values at both time points (p < 0.01). As result of the investigation of early childhood BMI trajectories in this pediatric cohort with monogenic obesity we suggest that BMI values >27.0 kg/m 2 or %BMI P95  > 140% at the age of 2 years and BMI values >33.0 kg/m 2 or %BMI P95  > 184% at the age of 5 years may be useful cut points to identify children who should undergo genetic screening for monogenic obesity due to functionally relevant mutations in the leptin gene or leptin receptor gene.

  14. Group X secreted phospholipase A2 limits the development of atherosclerosis in LDL receptor-null mice.

    PubMed

    Ait-Oufella, Hafid; Herbin, Olivier; Lahoute, Charlotte; Coatrieux, Christelle; Loyer, Xavier; Joffre, Jeremie; Laurans, Ludivine; Ramkhelawon, Bhama; Blanc-Brude, Olivier; Karabina, Sonia; Girard, Christophe A; Payré, Christine; Yamamoto, Kei; Binder, Christoph J; Murakami, Makoto; Tedgui, Alain; Lambeau, Gérard; Mallat, Ziad

    2013-03-01

    Several secreted phospholipases A2 (sPLA2s), including group IIA, III, V, and X, have been linked to the development of atherosclerosis, which led to the clinical testing of A-002 (varespladib), a broad sPLA2 inhibitor for the treatment of coronary artery disease. Group X sPLA2 (PLA2G10) has the most potent hydrolyzing activity toward phosphatidylcholine and is believed to play a proatherogenic role. Here, we show that Ldlr(-/-) mice reconstituted with bone marrow from mouse group X-deficient mice (Pla2g10(-/-)) unexpectedly display a doubling of plaque size compared with Pla2g10(+/+) chimeric mice. Macrophages of Pla2g10(-/-) mice are more susceptible to apoptosis in vitro, which is associated with a 4-fold increase of plaque necrotic core in vivo. In addition, chimeric Pla2g10(-/-) mice show exaggerated T lymphocyte (Th)1 immune response, associated with enhanced T-cell infiltration in atherosclerotic plaques. Interestingly, overexpression of human PLA2G10 in murine bone marrow cells leads to significant reduction of Th1 response and to 50% reduction of lesion size. PLA2G10 expression in bone marrow cells controls a proatherogenic Th1 response and limits the development of atherosclerosis. The results may provide an explanation for the recently reported inefficacy of A-002 (varespladib) to treat patients with coronary artery disease. Indeed, A-002 is a nonselective sPLA2 inhibitor that inhibits both proatherogenic (groups IIA and V) and antiatherogenic (group X) sPLA2s. Our results suggest that selective targeting of individual sPLA2 enzymes may be a better strategy to treat cardiovascular diseases.

  15. Increased atherosclerosis in mice with increased vascular biglycan content.

    PubMed

    Thompson, Joel C; Tang, Tao; Wilson, Patricia G; Yoder, Meghan H; Tannock, Lisa R

    2014-07-01

    The response to retention hypothesis of atherogenesis proposes that atherosclerosis is initiated via the retention of atherogenic lipoproteins by vascular proteoglycans. Co-localization studies suggest that of all the vascular proteoglycans, biglycan is the one most closely co-localized with LDL. The goal of this study was to determine if over-expression of biglycan in hyperlipidemic mice would increase atherosclerosis development. Transgenic mice were developed by expressing biglycan under control of the smooth muscle actin promoter, and were crossed to the LDL receptor deficient (C57BL/6 background) atherosclerotic mouse model. Biglycan transgenic and non-transgenic control mice were fed an atherogenic Western diet for 4-12 weeks. LDL receptor deficient mice overexpressing biglycan under control of the smooth muscle alpha actin promoter had increased atherosclerosis development that correlated with vascular biglycan content. Increased vascular biglycan content predisposes to increased lipid retention and increased atherosclerosis development. Published by Elsevier Ireland Ltd.

  16. Increased phospholipase A2 and lyso-phosphatidylcholine levels are associated with surfactant dysfunction in lung contusion injury in mice

    PubMed Central

    Machado-Aranda, David; Wang, Zhengdong; Yu, Bi; Suresh, M V; Notter, Robert H.; Raghavendran, Krishnan

    2012-01-01

    Objective Surfactant dysfunction is an important pathological disturbance in various forms of acute inflammatory lung injury. Previously we reported the presence of significant alterations in the composition and activity of pulmonary surfactant in blunt trauma-induced bilateral lung contusion (LC) injury in rats. This is extended here to a mouse model of unilateral LC, with a focus on compositional and functional surfactant changes associated with permeability injury and increases in activity of secretory phospholipase A2. Results Surfactant-associated gene expression was not significantly altered in mice with unilateral LC injury based on Affymetrix analysis. LC mice had significant permeability injury with increased albumin and total protein in bronchoalveolar lavage (BAL) at 5, 24, 48 and 72 h post-insult compared to uninjured controls. The percent content of large surfactant aggregates was significantly depleted at all post-injury times, and pulmonary pressure-volume (P-V) mechanics and compliance were abnormal over this period. Surfactant dysfunction was evaluated in mechanistic detail at 24 h, when permeability injury and P-V changes were most prominent. At this time, activity levels of secretory phospholipase A2 (PLA2) were increased in BAL, and chromatographic analysis showed that large surfactant aggregates had decreased levels of phosphatidylcholine (PC) and increased levels of lyso-PC. These changes were accompanied by severe detriments in large aggregate surface activity by pulsating bubble surfactometry. Large aggregates from LC mice at 24 h had minimum surface tensions of only 12.6±1.1 mN/m after prolonged bubble pulsation (20 min) compared to 0.7±0.03 mN/m for uninjured controls. Conclusion These results document significant detriments in the composition and activity of pulmonary surfactant in LC injury in mice, and suggest that active synthetic phospholipase-resistant exogenous surfactants may have future utility in treating surfactant dysfunction

  17. A novel method to generate T-cell receptor-deficient chimeric antigen receptor T cells.

    PubMed

    Kamiya, Takahiro; Wong, Desmond; Png, Yi Tian; Campana, Dario

    2018-03-13

    Practical methods are needed to increase the applicability and efficacy of chimeric antigen receptor (CAR) T-cell therapies. Using donor-derived CAR-T cells is attractive, but expression of endogenous T-cell receptors (TCRs) carries the risk for graft-versus-host-disease (GVHD). To remove surface TCRαβ, we combined an antibody-derived single-chain variable fragment specific for CD3ε with 21 different amino acid sequences predicted to retain it intracellularly. After transduction in T cells, several of these protein expression blockers (PEBLs) colocalized intracellularly with CD3ε, blocking surface CD3 and TCRαβ expression. In 25 experiments, median TCRαβ expression in T lymphocytes was reduced from 95.7% to 25.0%; CD3/TCRαβ cell depletion yielded virtually pure TCRαβ-negative T cells. Anti-CD3ε PEBLs abrogated TCRαβ-mediated signaling, without affecting immunophenotype or proliferation. In anti-CD3ε PEBL-T cells, expression of an anti-CD19-41BB-CD3ζ CAR induced cytokine secretion, long-term proliferation, and CD19 + leukemia cell killing, at rates meeting or exceeding those of CAR-T cells with normal CD3/TCRαβ expression. In immunodeficient mice, anti-CD3ε PEBL-T cells had markedly reduced GVHD potential; when transduced with anti-CD19 CAR, these T cells killed engrafted leukemic cells. PEBL blockade of surface CD3/TCRαβ expression is an effective tool to prepare allogeneic CAR-T cells. Combined PEBL and CAR expression can be achieved in a single-step procedure, is easily adaptable to current cell manufacturing protocols, and can be used to target other T-cell molecules to further enhance CAR-T-cell therapies. © 2018 by The American Society of Hematology.

  18. a2* Nicotinic Acetylcholine Receptors Influence Hippocampus-Dependent Learning and Memory in Adolescent Mice

    ERIC Educational Resources Information Center

    Lotfipour, Shahrdad; Mojica, Celina; Nakauchi, Sakura; Lipovsek, Marcela; Silverstein, Sarah; Cushman, Jesse; Tirtorahardjo, James; Poulos, Andrew; Elgoyhen, Ana Belén; Sumikawa, Katumi; Fanselow, Michael S.; Boulter, Jim

    2017-01-01

    The absence of a2* nicotinic acetylcholine receptors (nAChRs) in oriens lacunosum moleculare (OLM) GABAergic interneurons ablate the facilitation of nicotine-induced hippocampal CA1 long-term potentiation and impair memory. The current study delineated whether genetic mutations of a2* nAChRs ("Chrna2"[superscript L9'S/L9'S] and…

  19. Interleukin-21 receptor deficiency increases the initial toll-like receptor 2 response but protects against joint pathology by reducing Th1 and Th17 cells during streptococcal cell wall arthritis.

    PubMed

    Marijnissen, Renoud J; Roeleveld, Debbie M; Young, Deborah; Nickerson-Nutter, Cheryl; Abdollahi-Roodsaz, Shahla; Garcia de Aquino, Sabrina; van de Loo, Fons A J; van Spriel, Annemiek B; Boots, Annemieke M H; van den Berg, Wim B; Koenders, Marije I

    2014-04-01

    The cytokine interleukin-21 (IL-21) can have both proinflammatory and immunosuppressive effects. The purpose of this study was to investigate the potential dual role of IL-21 in experimental arthritis in relation to Th17 cells. Antigen-induced arthritis (AIA) and chronic streptococcal cell wall (SCW) arthritis were induced in IL-21 receptor-deficient (IL-21R(-/-) ) and wild-type mice. Knee joints, synovial tissue, and serum were analyzed for arthritis pathology and inflammatory markers. During AIA and chronic SCW arthritis, IL-21R deficiency protected against severe inflammation and joint destruction. This was accompanied by suppressed serum IgG1 levels and antigen-specific T cell responses. Levels of IL-17 were reduced during AIA, and synovial lymphocytes isolated during SCW arthritis for flow cytometry demonstrated that mainly IL-17+ interferon-γ (IFNγ)-positive T cells were reduced in IL-21R(-/-) mice. However, during the acute phases of SCW arthritis, significantly higher joint swelling scores were observed, consistent with enhanced tumor necrosis factor and IL-6 expression. Interestingly, IL-21R(-/-) mice were significantly less capable of up-regulating suppressor of cytokine signaling 1 (SOCS-1) and SOCS-3 messenger RNA. IL-21 stimulation also affected the Toll-like receptor 2 (TLR-2)/caspase recruitment domain 15 response to SCW fragments in vitro, indicating that impaired SOCS regulation in the absence of IL-21 signaling might contribute to the increased local activation during SCW arthritis. In contrast to the proinflammatory role of IL-21 in adaptive immunity, which drives IL-17+IFN+ cells and joint pathology during chronic experimental arthritis, IL-21 also has an important immunosuppressive role, presumably by inhibiting TLR signaling via SOCS-1 and SOCS-3. If this dual role of IL-21 in various immune processes is present in human disease, it could make IL-21 a difficult therapeutic target in rheumatoid arthritis. Copyright © 2014 by the American

  20. Bone Mineral Properties in Growing Col1a2+/G610C Mice, an animal model of Osteogenesis Imperfecta

    PubMed Central

    Masci, Marco; Wang, Min; Imbert, Laurianne; Barnes, Aileen M; Spevak, Lyudmila; Lukashova, Lyudmila; Yihe, Huang; Yan, Ma; Marini, Joan C; Jacobsen, Christina M; Warman, Matthew L; Boskey, Adele L

    2016-01-01

    The Col1a2+/G610C knock-in mouse, models osteogenesis imperfecta in a large old order Amish family (OOA) with type IV OI, caused by a G-to-T transversion at nucleotide 2098, which alters the gly-610 codon in the triple-helical domain of the α2(I) chain of type I collagen. Mineral and matrix properties of the long bones and vertebrae of male Col1a2+/G610C and their wild-type controls (Col1a2+/+), were characterized to gain insight into the role of α2-chain collagen mutations in mineralization. Additionally, we examined the rescuability of the composition by sclerostin inhibition initiated by crossing Col1a2+/G610C with an LRP+/A214V high bone mass allele. At age 10-days, vertebrae and tibia showed few alterations by micro-CT or Fourier transform infrared imaging (FTIRI). At 2-months-of-age, Col1a2+/G610C tibias had 13% fewer secondary trabeculae than Col1a2+/+, these were thinner (11%) and more widely spaced (20%) than those of Col1a2+/+ mice. Vertebrae of Col1a2+/G610C mice at 2-months also had lower bone volume fraction (38%), trabecular number (13%), thickness (13%) and connectivity density (32%) compared to Col1a2+/+. The cortical bone of Col1a2+/G610C tibias at 2-months had 3% higher tissue mineral density compared to Col1a2+/+; Col1a2+/G610C vertebrae had lower cortical thickness (29%), bone area (37%) and polar moment of inertia (38%) relative to Col1a2+/+. FTIRI analysis, which provides information on bone chemical composition at ~ 7 µm-spatial resolution, showed tibias at 10-days, did not differ between genotypes. Comparing identical bone types in Col1a2+/G610C to Col1a2+/+ at 2-months-of-age, tibias showed higher mineral-to-matrix ratio in trabeculae (17%) and cortices (31%). and in vertebral cortices (28%). Collagen maturity was 42% higher at 10-days-of-age in Col1a2+/G610C vertebral trabeculae and in 2-month tibial cortices (12%), vertebral trabeculae (42%) and vertebral cortices (12%). Higher acid-phosphate substitution was noted in 10-day

  1. Bone mineral properties in growing Col1a2(+/G610C) mice, an animal model of osteogenesis imperfecta.

    PubMed

    Masci, Marco; Wang, Min; Imbert, Laurianne; Barnes, Aileen M; Spevak, Lyudmila; Lukashova, Lyudmila; Huang, Yihe; Ma, Yan; Marini, Joan C; Jacobsen, Christina M; Warman, Matthew L; Boskey, Adele L

    2016-06-01

    The Col1a2(+/G610C) knock-in mouse, models osteogenesis imperfecta in a large old order Amish family (OOA) with type IV OI, caused by a G-to-T transversion at nucleotide 2098, which alters the gly-610 codon in the triple-helical domain of the α2(I) chain of type I collagen. Mineral and matrix properties of the long bones and vertebrae of male Col1a2(+/G610C) and their wild-type controls (Col1a2(+/+)), were characterized to gain insight into the role of α2-chain collagen mutations in mineralization. Additionally, we examined the rescuability of the composition by sclerostin inhibition initiated by crossing Col1a2(+/G610C) with an LRP(+/A214V) high bone mass allele. At age 10-days, vertebrae and tibia showed few alterations by micro-CT or Fourier transform infrared imaging (FTIRI). At 2-months-of-age, Col1a2(+/G610C) tibias had 13% fewer secondary trabeculae than Col1a2(+/+), these were thinner (11%) and more widely spaced (20%) than those of Col1a2(+/+) mice. Vertebrae of Col1a2(+/G610C) mice at 2-months also had lower bone volume fraction (38%), trabecular number (13%), thickness (13%) and connectivity density (32%) compared to Col1(a2+/+). The cortical bone of Col1a2(+/G610C) tibias at 2-months had 3% higher tissue mineral density compared to Col1a2(+/+); Col1a2(+/G610C) vertebrae had lower cortical thickness (29%), bone area (37%) and polar moment of inertia (38%) relative to Col1a2(+/+). FTIRI analysis, which provides information on bone chemical composition at ~7μm-spatial resolution, showed tibias at 10-days did not differ between genotypes. Comparing identical bone types in Col1a2(+/G610C) to Col1a2(+/+) at 2-months-of-age, tibias showed higher mineral-to-matrix ratio in trabeculae (17%) and cortices (31%). and in vertebral cortices (28%). Collagen maturity was 42% higher at 10-days-of-age in Col1a2(+/G610C) vertebral trabeculae and in 2-month tibial cortices (12%), vertebral trabeculae (42%) and vertebral cortices (12%). Higher acid-phosphate substitution

  2. Adenosine A(2A) receptor modulation of hippocampal CA3-CA1 synapse plasticity during associative learning in behaving mice.

    PubMed

    Fontinha, Bruno M; Delgado-García, José M; Madroñal, Noelia; Ribeiro, Joaquim A; Sebastião, Ana M; Gruart, Agnès

    2009-06-01

    Previous in vitro studies have characterized the electrophysiological and molecular signaling pathways of adenosine tonic modulation on long-lasting synaptic plasticity events, particularly for hippocampal long-term potentiation (LTP). However, it remains to be elucidated whether the long-term changes produced by endogenous adenosine in the efficiency of synapses are related to those required for learning and memory formation. Our goal was to understand how endogenous activation of adenosine excitatory A(2A) receptors modulates the associative learning evolution in conscious behaving mice. We have studied here the effects of the application of a highly selective A(2A) receptor antagonist, SCH58261, upon a well-known associative learning paradigm-classical eyeblink conditioning. We used a trace paradigm, with a tone as the conditioned stimulus (CS) and an electric shock presented to the supraorbital nerve as the unconditioned stimulus (US). A single electrical pulse was presented to the Schaffer collateral-commissural pathway to evoke field EPSPs (fEPSPs) in the pyramidal CA1 area during the CS-US interval. In vehicle-injected animals, there was a progressive increase in the percentage of conditioning responses (CRs) and in the slope of fEPSPs through conditioning sessions, an effect that was completely prevented (and lost) in SCH58261 (0.5 mg/kg, i.p.) -injected animals. Moreover, experimentally evoked LTP was impaired in SCH58261-injected mice. In conclusion, the endogenous activation of adenosine A(2A) receptors plays a pivotal effect on the associative learning process and its relevant hippocampal circuits, including activity-dependent changes at the CA3-CA1 synapse.

  3. Comparison of Systemic Toxicity between Botulinum Toxin Subtypes A1 and A2 in Mice and Rats.

    PubMed

    Torii, Yasushi; Goto, Yoshitaka; Nakahira, Shinji; Kozaki, Shunji; Kaji, Ryuji; Ginnaga, Akihiro

    2015-06-01

    The adverse events caused by botulinum toxin type A (subtype A1) product, thought to be after-effects of toxin diffusion after high-dose administration, have become serious issues. A preparation showing less diffusion in the body than existing drugs has been sought. We have attempted to produce neurotoxin derived from subtype A2 (A2NTX) with an amino acid sequence different from that of neurotoxin derived from subtype A1 (A1NTX). In this study, to investigate whether A2NTX has the potential to resolve these issues, we compared the safety of A2NTX, a progenitor toxin derived from subtype A1 (A1 progenitor toxin) and A1NTX employing the intramuscular lethal dose 50% (im LD50) in mice and rats and the compound muscle action potential (CMAP) in rats. Mouse im LD50 values for A1 progenitor toxin and A2NTX were 93 and 166 U/kg, respectively, and the rat im LD50 values were 117 and 153 U/kg, respectively. In the rat CMAP test, the dose on the contralateral side, which caused a 50% reduction in the CMAP amplitude, that is, CMAP-TD50 , was calculated as 19.0, 16.6 and 28.7 U/kg for A1 progenitor toxin, A1NTX and A2NTX, respectively. The results indicate that A2NTX is safer than A1 progenitor toxin and A1NTX. © 2014 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  4. Inhibitory effect of a potent and selective cytosolic phospholipase A2alpha inhibitor RSC-3388 on skin inflammation in mice.

    PubMed

    Yamamoto, Mina; Haruna, Takayo; Imura, Kinichi; Hikita, Ichiro; Furue, Yoko; Higashino, Kenichi; Gahara, Yoshinari; Deguchi, Masashi; Yasui, Kiyoshi; Arimura, Akinori

    2008-01-01

    Cytosolic phospholipase A2alpha (cPLA2alpha) preferentially hydrolyzes membrane phospholipids containing arachidonic acid, resulting in the biosynthesis of eicosanoids such as prostaglandins and leukotrienes. To examine the contribution of cPLA2alpha to skin inflammation, we evaluated the effect of (E)-N-[(2S,4R)-4-[N-(biphenyl-2-ylmethyl)-N-2-methylpropylamino]-1-[2-(2,4-difluorobenzoyl)benzoyl]pyrrolidin- 2-yl]methyl-3-[4-(2,4-dioxothiazolidin-5-ylidenemethyl) phenyl]acrylamide (RSC-3388), a potent and selective cPLA2alpha inhibitor, on 2,4,6-trinitro-1-chlorobenzene (TNCB)-induced ear inflammation and mite antigen-induced dermatitis in mice. Topical application of RSC-3388 showed a significant inhibitory activity against TNCB-induced ear swelling and eicosanoid production in mice. Comprehensive expression analysis using Gene-Chip technology and subsequent experiments concerning mRNA and protein expression demonstrated that RSC-3388 clearly reduced the levels of interleukin-1beta, macrophage inflammatory protein-1alpha (MIP-1alpha) and MIP-1beta in a TNCB-induced mouse model. In addition, RSC-3388 ointment significantly alleviated atopic dermatitis-like skin lesions induced by repeated application of mite antigen. Furthermore, increased expression of cPLA(2)alpha, assessed by anti-phospho-cPLA2alpha antibody, was observed in the skin lesions of mite-antigen-induced dermatitis. These results indicate that cPLA2alpha is involved in the development of skin inflammation in mice, and RSC-3388 is expected to be useful for the treatment of inflammatory skin disorders such as atopic dermatitis. (c) 2008 S. Karger AG, Basel

  5. LASSBio-897 Reduces Lung Injury Induced by Silica Particles in Mice: Potential Interaction with the A2A Receptor

    PubMed Central

    Carvalho, Vinicius F.; Ferreira, Tatiana P. T.; de Arantes, Ana C. S.; Noël, François; Tesch, Roberta; Sant’Anna, Carlos M. R.; Barreiro, Eliezer J. L.; Fraga, Carlos A. M.; Rodrigues e Silva, Patrícia M.; Martins, Marco A.

    2017-01-01

    Silicosis is a lethal fibro-granulomatous pulmonary disease highly prevalent in developing countries, for which no proper therapy is available. Among a small series of N-acylhydrazones, the safrole-derived compound LASSBio-897 (3-thienylidene-3, 4-methylenedioxybenzoylhydrazide) raised interest due to its ability to bind to the adenosine A2A receptor. Here, we evaluated the anti-inflammatory and anti-fibrotic potential of LASSBio-897, exploring translation to a mouse model of silicosis and the A2A receptor as a site of action. Pulmonary mechanics, inflammatory, and fibrotic changes were assessed 28 days after intranasal instillation of silica particles in Swiss–Webster mice. Glosensor cAMP HEK293G cells, CHO cells stably expressing human adenosine receptors and ligand binding assay were used to evaluate the pharmacological properties of LASSBio-897 in vitro. Molecular docking studies of LASSBio-897 were performed using the genetic algorithm software GOLD 5.2. We found that the interventional treatment with the A2A receptor agonist CGS 21680 reversed silica particle-induced airway hyper-reactivity as revealed by increased responses of airway resistance and lung elastance following aerosolized methacholine. LASSBio-897 (2 and 5 mg/kg, oral) similarly reversed pivotal lung pathological features of silicosis in this model, reducing levels of airway resistance and lung elastance, granuloma formation and collagen deposition. In competition assays, LASSBio-897 decreased the binding of the selective A2A receptor agonist [3H]-CGS21680 (IC50 = 9.3 μM). LASSBio-897 (50 μM) induced modest cAMP production in HEK293G cells, but it clearly synergized the cAMP production by adenosine in a mechanism sensitive to the A2A antagonist SCH 58261. This synergism was also seen in CHO cells expressing the A2A, but not those expressing A2B, A1 or A3 receptors. Based on the evidence that LASSBio-897 binds to A2A receptor, molecular docking studies were performed using the A2A receptor

  6. Bee Venom Phospholipase A2 Alleviate House Dust Mite-Induced Atopic Dermatitis-Like Skin Lesions by the CD206 Mannose Receptor.

    PubMed

    Shin, Dasom; Choi, Won; Bae, Hyunsu

    2018-04-02

    Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by highly pruritic, erythematous, and eczematous skin plaques. We previously reported that phospholipase A2 (PLA2) derived from bee venom alleviates AD-like skin lesions induced by 2,4-dinitrochlorobenzene (DNCB) and house dust mite extract ( Dermatophagoides farinae extract, DFE) in a murine model. However, the underlying mechanisms of PLA2 action in actopic dermatitis remain unclear. In this study, we showed that PLA2 treatment inhibited epidermal thickness, serum immunoglobulin E (IgE) and cytokine levels, macrophage and mast cell infiltration in the ear of an AD model induced by DFE and DNCB. In contrast, these effects were abrogated in CD206 mannose receptor-deficient mice exposed to DFE and DNCB in the ear. These data suggest that bvPLA2 alleviates atopic skin inflammation via interaction with CD206.

  7. Behavioural and biochemical responses to morphine associated with its motivational properties are altered in adenosine A2A receptor knockout mice

    PubMed Central

    Castañé, A; Wells, L; Soria, G; Hourani, S; Ledent, C; Kitchen, I; Opacka-Juffry, J; Maldonado, R; Valverde, O

    2008-01-01

    Background and purpose: The purinergic system through the A2A adenosine receptor regulates addiction induced by different drugs of abuse. The aim of the present study was to investigate the specific role of A2A adenosine receptors (A2ARs) in the behavioural and neurochemical responses to morphine associated with its motivational properties. Experimental approach: Mice lacking A2ARs (A2A knockout (KO) mice) and wild-type littermates were used to evaluate behavioural responses induced by morphine. Antinociception was assessed using the tail-immersion and the hot-plate tests. Place-conditioning paradigms were used to evaluate the rewarding effects of morphine and the dysphoric responses of morphine withdrawal. Microdialysis studies were carried out to evaluate changes in the extracellular levels of dopamine in the nucleus accumbens of A2A KO mice after morphine administration. Key results: The acute administration of morphine induced a similar enhancement of locomotor activity and antinociceptive responses in both genotypes. However, the rewarding effects induced by morphine were completely blocked in A2A KO mice. Also, naloxone did not induce place aversion in animals lacking the A2ARs. Conclusions and implications: Our findings demonstrate that the rewarding and aversive effects associated with morphine abstinence were abolished in A2A KO mice, supporting a differential role of the A2A adenosine receptor in the somatic and motivational effects of morphine addiction. This study provides evidence for the role of A2ARs as general modulators of the motivational properties of drugs of abuse. Pharmacological manipulation of these receptors may represent a new target in the management of drug addiction. PMID:18660831

  8. Ozagrel hydrochloride, a selective thromboxane A2 synthase inhibitor, alleviates liver injury induced by acetaminophen overdose in mice

    PubMed Central

    2013-01-01

    Background Overdosed acetaminophen (paracetamol, N-acetyl-p-aminophenol; APAP) causes severe liver injury. We examined the effects of ozagrel, a selective thromboxane A2 (TXA2) synthase inhibitor, on liver injury induced by APAP overdose in mice. Methods Hepatotoxicity was induced to ICR male mice by an intraperitoneal injection with APAP (330 mg/kg). The effects of ozagrel (200 mg/kg) treatment 30 min after the APAP injection were evaluated with mortality, serum alanine aminotransferase (ALT) levels and hepatic changes, including histopathology, DNA fragmentation, mRNA expression and total glutathione contents. The impact of ozagrel (0.001-1 mg/mL) on cytochrome P450 2E1 (CYP2E1) activity in mouse hepatic microsome was examined. RLC-16 cells, a rat hepatocytes cell line, were exposed to 0.25 mM N-acetyl-p-benzoquinone imine (NAPQI), a hepatotoxic metabolite of APAP. In this model, the cytoprotective effects of ozagrel (1–100 muM) were evaluated by the WST-1 cell viability assay. Results Ozagel treatment significantly attenuated higher mortality, elevated serum alanine aminotransferase levels, excessive hepatic centrilobular necrosis, hemorrhaging and DNA fragmentation, as well as increase in plasma 2,3-dinor thromboxane B2 levels induced by APAP injection. Ozagrel also inhibited the hepatic expression of cell death-related mRNAs induced by APAP, such as jun oncogene, FBJ osteosarcoma oncogene (fos) and C/EBP homologous protein (chop), but did not suppress B-cell lymphoma 2-like protein11 (bim) expression and hepatic total glutathione depletion. These results show ozagrel can inhibit not all hepatic changes but can reduce the hepatic necrosis. Ozagrel had little impact on CYP2E1 activity involving the NAPQI production. In addition, ozagrel significantly attenuated cell injury induced by NAPQI in RLC-16. Conclusions We demonstrate that the TXA2 synthase inhibitor, ozagrel, dramatically alleviates liver injury induced by APAP in mice, and suggest that it is a

  9. Hepatoprotective effects of litchi (Litchi chinensis) procyanidin A2 on carbon tetrachloride-induced liver injury in ICR mice.

    PubMed

    Chen, Lih-Geeng; Chang, Cheng-Wei; Tsay, Jwu-Guh; Weng, Brian Bor-Chun

    2017-06-01

    Drug tolerance, lacking liver regenerative activity and inconclusive inhibition of steatosis and cirrhosis by silymarin treatment during chronic liver injury have increased the demand for novel alternative or synergistic treatments for liver damage. Litchi fruit is abundant in polyphenolic compounds and is used in traditional Chinese medicine for treatments that include the strengthening of hepatic and pancreatic functions. Unique polyphenolic compounds obtained from litchi pericarp extract (LPE) were studied in vitro and in vivo for hepatoprotection. Epicatechin (EC) and procyanidin A2 (PA2) of LPE were obtained by fractionated-extraction from pulverized litchi pericarps. All fractions, including LPE, were screened against silymarin in carbon tetrachloride (CCl 4 )-treated murine embryonic liver cell line (BNL). The effects of daily gavage-feeding of LPE, silymarin (200 mg/kg body weight) or H 2 O in CCl 4 -intoxicated male ICR mice were evaluated by studying serum chemicals, liver pathology and glutathione antioxidative enzymes. The effects of EC and PA2 on liver cell regenerative activity were investigated using a scratch wound healing assay and flow cytometric cell cycle analysis; the results of which demonstrated that LPE protected BNL from CCl 4 -intoxication. Gavage-feeding of LPE decreased serum glutamic oxaloacetate transaminase and glutamic pyruvic transaminase levels, and exhibited superior retention of the hexagonal structure of hepatocytes and reduced necrotic cells following liver histopathological examinations in CCl 4- intoxicated ICR mice. Glutathione peroxidise and glutathione reductase activities were preserved as the normal control level in LPE groups. EC and PA2 were principle components of LPE. PA2 demonstrated liver cell regenerative activity in scratch wound healing assays and alcohol-induced liver cell injury in vitro . The present findings suggest that litchi pericarp polyphenolic extracts, including EC and PA2, may be a synergistic

  10. Hepatoprotective effects of litchi (Litchi chinensis) procyanidin A2 on carbon tetrachloride-induced liver injury in ICR mice

    PubMed Central

    Chen, Lih-Geeng; Chang, Cheng-Wei; Tsay, Jwu-Guh; Weng, Brian Bor-Chun

    2017-01-01

    Drug tolerance, lacking liver regenerative activity and inconclusive inhibition of steatosis and cirrhosis by silymarin treatment during chronic liver injury have increased the demand for novel alternative or synergistic treatments for liver damage. Litchi fruit is abundant in polyphenolic compounds and is used in traditional Chinese medicine for treatments that include the strengthening of hepatic and pancreatic functions. Unique polyphenolic compounds obtained from litchi pericarp extract (LPE) were studied in vitro and in vivo for hepatoprotection. Epicatechin (EC) and procyanidin A2 (PA2) of LPE were obtained by fractionated-extraction from pulverized litchi pericarps. All fractions, including LPE, were screened against silymarin in carbon tetrachloride (CCl4)-treated murine embryonic liver cell line (BNL). The effects of daily gavage-feeding of LPE, silymarin (200 mg/kg body weight) or H2O in CCl4-intoxicated male ICR mice were evaluated by studying serum chemicals, liver pathology and glutathione antioxidative enzymes. The effects of EC and PA2 on liver cell regenerative activity were investigated using a scratch wound healing assay and flow cytometric cell cycle analysis; the results of which demonstrated that LPE protected BNL from CCl4-intoxication. Gavage-feeding of LPE decreased serum glutamic oxaloacetate transaminase and glutamic pyruvic transaminase levels, and exhibited superior retention of the hexagonal structure of hepatocytes and reduced necrotic cells following liver histopathological examinations in CCl4-intoxicated ICR mice. Glutathione peroxidise and glutathione reductase activities were preserved as the normal control level in LPE groups. EC and PA2 were principle components of LPE. PA2 demonstrated liver cell regenerative activity in scratch wound healing assays and alcohol-induced liver cell injury in vitro. The present findings suggest that litchi pericarp polyphenolic extracts, including EC and PA2, may be a synergistic alternative to

  11. Out of frame peptides from BCR/ABL alternative splicing are immunogenic in HLA A2.1 transgenic mice.

    PubMed

    Casnici, C; Volpe, G; Lattuada, D; Crotta, K; Kuka, M; Panuzzo, C; Mastrotto, C; Tonon, G; Fazio, V M; Saglio, G; Marelli, O

    2009-04-08

    New, potentially tumor-specific antigens have been described in Bcr/Abl positive leukemias. Besides the main BCR/ABL hybrid fusion transcripts, a small number of transcripts derived from alternative splicing between BCR exons 1, 13, and 14 with ABL exons 4 and 5 have been identified. These variants are expressed in chronic myelogenous leukemia and acute lymphocytic leukemia patients. The transcriptional products were characterized at their C-terminus by a large amino acid portion derived from out of frame (OOF) reading of the ABL gene. This OOF peptide is expressed only in leukemic cells and has no homology with known human proteins. In order to study an in vivo model, three 39-amino acid peptides, each corresponding to a third of the whole human OOF peptide sequence, were tested for their capacity to elicit specific immune responses in HLA A2.1 transgenic mice. Peptides A and B, but not C, induced the production of specific antisera, while A and C induced the generation of specific cytotoxic T lymphocytes.

  12. Aldehyde Dehydrogenases 1A2 Expression and Distribution are Potentially Associated with Neuron Death in Spinal Cord of Tg(SOD1*G93A)1Gur Mice.

    PubMed

    Liang, Huiting; Wu, Chengsi; Deng, Youqing; Zhu, Lei; Zhang, Jie; Gan, Weiming; Tang, Chunyan; Xu, Renshi

    2017-01-01

    The pathogenesis of amyotrophic lateral sclerosis (ALS) has not been unclear yet, it might be associated with the abnormal expression and distribution of certain proteins. Aldehyde dehydrogenases 1A2 (ALDH1A2) was thought to be one of potential candidates. Therefore, in this study we observed and analyzed the alteration of the expression and distribution of ALDH1A2 in the spinal cord of wild-type (WT) and Tg(SOD1*G93A)1Gur mice. We compared the expression and distribution of ALDH1A2 in the different segments, anatomic regions and neural cells of spinal cord at the different stages of WT and Tg(SOD1*G93A)1Gur mice applied the methods of fluorescent immunohistochemistry and western blot. Results revealed that ALDH1A2 extensively expressed and distributed in the spinal cord of adult WT and Tg(SOD1*G93A)1Gur mice. The expression and distribution of ALDH1A2 in the white matter including the anterior, posterior and lateral funiculus were more than that in the gray matter including the central canal, the anterior and dorsal horn. ALDH1A2 majorly expressed and distributed in the astrocyte, microglial, oligodendrocyte and neuron cells. The ALDH1A2 expression significantly decreased and redistributed in some anatomic regions of spinal cord at the onset and progression stages of Tg(SOD1*G93A)1Gur mice. The expression decrease of ALDH1A2 followed with the increase of neuron cells death. This study suggested that the alteration of expression and distribution of ALDH1A2 was potentially associated with the pathogenesis of ALS.

  13. 5-HT2A receptor deficiency alters the metabolic and transcriptional, but not the behavioral, consequences of chronic unpredictable stress.

    PubMed

    Jaggar, Minal; Weisstaub, Noelia; Gingrich, Jay A; Vaidya, Vidita A

    2017-12-01

    Chronic stress enhances risk for psychiatric disorders, and in animal models is known to evoke depression-like behavior accompanied by perturbed neurohormonal, metabolic, neuroarchitectural and transcriptional changes. Serotonergic neurotransmission, including serotonin 2A (5-HT 2A ) receptors, have been implicated in mediating specific aspects of stress-induced responses. Here we investigated the influence of chronic unpredictable stress (CUS) on depression-like behavior, serum metabolic measures, and gene expression in stress-associated neurocircuitry of the prefrontal cortex (PFC) and hippocampus in 5-HT 2A receptor knockout (5-[Formula: see text]) and wild-type mice of both sexes. While 5-[Formula: see text] male and female mice exhibited a baseline reduced anxiety-like state, this did not alter the onset or severity of behavioral despair during and at the cessation of CUS, indicating that these mice can develop stress-evoked depressive behavior. Analysis of metabolic parameters in serum revealed a CUS-evoked dyslipidemia, which was abrogated in 5-[Formula: see text] female mice with a hyperlipidemic baseline phenotype. 5-[Formula: see text] male mice in contrast did not exhibit such a baseline shift in their serum lipid profile. Specific stress-responsive genes ( Crh , Crhr1 , Nr3c1, and Nr3c2 ), trophic factors ( Bdnf , Igf1 ) and immediate early genes (IEGs) ( Arc , Fos , Fosb , Egr1-4 ) in the PFC and hippocampus were altered in 5-[Formula: see text] mice both under baseline and CUS conditions. Our results support a role for the 5-HT 2A receptor in specific metabolic and transcriptional, but not behavioral, consequences of CUS, and highlight that the contribution of the 5-HT 2A receptor to stress-evoked changes is sexually dimorphic.

  14. Genetic manipulation of the ghrelin signaling system in male mice reveals bone compartment specificity of acylated and unacylated ghrelin in the regulation of bone remodeling

    USDA-ARS?s Scientific Manuscript database

    Ghrelin receptor-deficient (Ghsr-/-) mice that lack acylated ghrelin (AG) signaling retain a metabolic response to unacylated ghrelin (UAG). Recently, we showed that Ghsr-deficiency affects bone metabolism. The aim of this study was to further establish the impact of AG and UAG on bone metabolism. W...

  15. Bee Venom Phospholipase A2 Protects against Acetaminophen-Induced Acute Liver Injury by Modulating Regulatory T Cells and IL-10 in Mice

    PubMed Central

    Kim, Hyunseong; Keum, Dong June; Kwak, Jung won; Chung, Hwan-Suck; Bae, Hyunsu

    2014-01-01

    The aim of this study was to investigate the protective effects of phospholipase A2 (PLA2) from bee venom against acetaminophen-induced hepatotoxicity through CD4+CD25+Foxp3+ T cells (Treg) in mice. Acetaminophen (APAP) is a widely used antipyretic and analgesic, but an acute or cumulative overdose of acetaminophen can cause severe hepatic failure. Tregs have been reported to possess protective effects in various liver diseases and kidney toxicity. We previously found that bee venom strongly increased the Treg population in splenocytes and subsequently suppressed immune disorders. More recently, we found that the effective component of bee venom is PLA2. Thus, we hypothesized that PLA2 could protect against liver injury induced by acetaminophen. To evaluate the hepatoprotective effects of PLA2, C57BL/6 mice or interleukin-10-deficient (IL-10−/−) mice were injected with PLA2 once a day for five days and sacrificed 24 h (h) after acetaminophen injection. The blood sera were collected 0, 6, and 24 h after acetaminophen injection for the analysis of aspartate aminotransferase (AST) and alanine aminotransferase (ALT). PLA2-injected mice showed reduced levels of serum AST, ALT, proinflammatory cytokines, and nitric oxide (NO) compared with the PBS-injected control mice. However, IL-10 was significantly increased in the PLA2-injected mice. These hepatic protective effects were abolished in Treg-depleted mice by antibody treatment and in IL-10−/− mice. Based on these findings, it can be concluded that the protective effects of PLA2 against acetaminophen-induced hepatotoxicity can be mediated by modulating the Treg and IL-10 production. PMID:25478691

  16. Bee venom phospholipase A2 protects against acetaminophen-induced acute liver injury by modulating regulatory T cells and IL-10 in mice.

    PubMed

    Kim, Hyunseong; Keum, Dong June; Kwak, Jung won; Chung, Hwan-Suck; Bae, Hyunsu

    2014-01-01

    The aim of this study was to investigate the protective effects of phospholipase A2 (PLA2) from bee venom against acetaminophen-induced hepatotoxicity through CD4+CD25+Foxp3+ T cells (Treg) in mice. Acetaminophen (APAP) is a widely used antipyretic and analgesic, but an acute or cumulative overdose of acetaminophen can cause severe hepatic failure. Tregs have been reported to possess protective effects in various liver diseases and kidney toxicity. We previously found that bee venom strongly increased the Treg population in splenocytes and subsequently suppressed immune disorders. More recently, we found that the effective component of bee venom is PLA2. Thus, we hypothesized that PLA2 could protect against liver injury induced by acetaminophen. To evaluate the hepatoprotective effects of PLA2, C57BL/6 mice or interleukin-10-deficient (IL-10-/-) mice were injected with PLA2 once a day for five days and sacrificed 24 h (h) after acetaminophen injection. The blood sera were collected 0, 6, and 24 h after acetaminophen injection for the analysis of aspartate aminotransferase (AST) and alanine aminotransferase (ALT). PLA2-injected mice showed reduced levels of serum AST, ALT, proinflammatory cytokines, and nitric oxide (NO) compared with the PBS-injected control mice. However, IL-10 was significantly increased in the PLA2-injected mice. These hepatic protective effects were abolished in Treg-depleted mice by antibody treatment and in IL-10-/- mice. Based on these findings, it can be concluded that the protective effects of PLA2 against acetaminophen-induced hepatotoxicity can be mediated by modulating the Treg and IL-10 production.

  17. Impact of CCL2 and CCR2 Chemokine / Receptor Deficiencies on Macrophage Recruitment and Continuous Glucose Monitoring in vivo

    PubMed Central

    Klueh, Ulrike; Czajkowski, Caroline; Ludzinska, Izabela; Qiao, Yi; Frailey, Jackman; Kreutzer, Donald L.

    2016-01-01

    The accumulation of macrophages (MΦ) at the sensor-tissue interface is thought to be a major player in controlling tissue reactions and sensor performance in vivo. Nevertheless until recently no direct demonstration of the causal relationship between MΦ aggregation and loss of sensor function existed. Using a Continuous Glucose Monitoring (CGM) murine model we previously demonstrated that genetic deficiencies of MΦ or depletion of MΦ decreased MΦ accumulation at sensor implantation sites, which led to significantly enhanced CGM performance, when compared to normal mice. Additional studies in our laboratories have also demonstrated that MΦ can act as “metabolic sinks” by depleting glucose levels at the implanted sensors in vitro and in vivo. In the present study we extended these observations by demonstrating that MΦ chemokine (CCL2) and receptor (CCR2) knockout mice displayed a decrease in inflammation and MΦ recruitment at sensor implantation sites, when compared to normal mice. This decreased MΦ recruitment significantly enhanced CGM performance when compared to control mice. These studies demonstrated the importance of the CCL2 family of chemokines and related receptors in MΦ recruitment and sensor performance and suggest chemokine targets for enhancing CGM in vivo. PMID:27376197

  18. Role of CYP epoxygenases in A2A AR-mediated relaxation using A2A AR-null and wild-type mice.

    PubMed

    Nayeem, Mohammed A; Poloyac, Samuel M; Falck, John R; Zeldin, Darryl C; Ledent, Catherine; Ponnoth, Dovenia S; Ansari, Habib R; Mustafa, S Jamal

    2008-11-01

    We hypothesized that A2A adenosine receptor (A2A AR) activation causes vasorelaxation through cytochrome P-450 (CYP) epoxygenases and endothelium-derived hyperpolarizing factors, whereas lack of A2A AR activation promotes vasoconstriction through Cyp4a in the mouse aorta. Adenosine 5'-N-ethylcarboxamide (NECA; 10(-6) M), an adenosine analog, caused relaxation in wild-type A2A AR (A2A AR+/+; +33.99 +/- 4.70%, P < 0.05) versus contraction in A2A AR knockout (A2A AR(-/-); -27.52 +/- 4.11%) mouse aortae. An A2A AR-specific antagonist (SCH-58261; 1 microM) changed the NECA (10(-6) M) relaxation response to contraction (-35.82 +/- 4.69%, P < 0.05) in A2A AR+/+ aortae, whereas no effect was noted in A2A AR(-/-) aortae. Significant contraction was seen in the absence of the endothelium in A2A AR+/+ (-2.58 +/- 2.25%) aortae compared with endothelium-intact aortae. An endothelial nitric oxide synthase inhibitor (N-nitro-L-arginine methyl ester; 100 microM) and a cyclooxygenase inhibitor (indomethacin; 10 microM) failed to block NECA-induced relaxation in A2A AR+/+ aortae. A selective inhibitor of CYP epoxygenases (methylsulfonyl-propargyloxyphenylhexanamide; 10 microM) changed NECA-mediated relaxation (-22.74 +/- 5.11% at 10(-6) M) and CGS-21680-mediated relaxation (-18.54 +/- 6.06% at 10(-6) M) to contraction in A2A AR+/+ aortae, whereas no response was noted in A2A AR(-/-) aortae. Furthermore, an epoxyeicosatrienoic acid (EET) antagonist [14,15-epoxyeicosa-5(Z)-enoic acid; 10 microM] was able to block NECA-induced relaxation in A2A AR+/+ aortae, whereas omega-hydroxylase inhibitors (10 microM dibromo-dodecenyl-methylsulfimide and 10 microM HET-0016) changed contraction into relaxation in A2A AR(-/-) aorta. Cyp2c29 protein was upregulated in A2A AR+/+ aortae, whereas Cyp4a was upregulated in A2A AR(-/-) aortae. Higher levels of dihydroxyeicosatrienoic acids (DHETs; 14,15-DHET, 11,12-DHET, and 8,9-DHET, P < 0.05) were found in A2A AR+/+ versus A2A AR(-/-) aortae. EET levels

  19. Adenosine A2A Receptors Mediate Anti-Inflammatory Effects of Electroacupuncture on Synovitis in Mice with Collagen-Induced Arthritis

    PubMed Central

    Li, Qi-hui; Xie, Wen-xia; Li, Xiao-pei; Huang, Ka-te; Du, Zhong-heng; Cong, Wen-jie; Zhou, Long-hua; Ye, Tian-shen; Chen, Jiang-Fan

    2015-01-01

    To study the role of adenosine A2A receptor (A2AR) in mediating the anti-inflammatory effect of electroacupuncture (EA) on synovitis in collagen-induced arthritis (CIA), C57BL/6 mice were divided into five treatment groups: Sham-control, CIA-control, CIA-EA, CIA-SCH58261 (A2AR antagonist), and CIA-EA-SCH58261. All mice except those in the Sham-control group were immunized with collagen II for arthritis induction. EA treatment was administered using the stomach 36 and spleen 6 points, and stimulated with a continuous rectangular wave for 30 min daily. EA treatment and SCH58261 were administered daily from days 35 to 49 (n = 10). After treatment, X-ray radiography of joint bone morphology was established at day 60 and mouse blood was collected for ELISA determination of tumor necrosis factor alpha (TNF-α) levels. Mice were sacrificed and processed for histological examination of pathological changes of joint tissue, including hematoxylin-eosin staining and immunohistochemistry of A2AR expression. EA treatment resulted in significantly reduced pathological scores, TNF-α concentrations, and bone damage X-ray scores. Importantly, the anti-inflammatory and tissue-protective effect of EA treatment was reversed by coadministration of SCH58261. Thus, EA treatment exerts an anti-inflammatory effect resulting in significant protection of cartilage by activation of A2AR in the synovial tissue of CIA. PMID:25784951

  20. Group X secretory phospholipase A2 augments Angiotensin II-induced inflammatory responses and abdominal aortic aneurysm formation in apoE-deficient mice

    PubMed Central

    Zack, Melissa; Boyanovsky, Boris B.; Shridas, Preetha; Bailey, William; Forrest, Kathy; Howatt, Deborah A.; Gelb, Michael H.; de Beer, Frederick C.; Daugherty, Alan; Webb, Nancy R.

    2010-01-01

    Objective Abdominal aortic aneurysm (AAA) is a complex vascular disease characterized by matrix degradation and inflammation and is a major cause of mortality in older men. Specific interventions that prevent AAA progression remain to be identified. In this study, we tested the hypothesis that Group X secretory phospholipase A2 (GX sPLA2), an enzyme implicated in inflammatory processes, mediates AAA. Methods and Results GX sPLA2 was detected by immunostaining in human aneurysmal tissue and in angiotensin II (Ang II)-induced AAAs in apolipoprotein E-deficient (apoE−/−) mice. GX sPLA2 mRNA was increased significantly (11-fold) in abdominal aortas of apoE−/− mice in response to Ang II infusion. To define the role of GX sPLA2 in experimental AAAs, apoE−/− and apoE−/− × GX sPLA2−/− (GX DKO) mice were infused with Ang II for either 10 (n=7) or 28 (n=24–26) days. Deficiency of GX sPLA2 significantly reduced the incidence and severity of AAAs, as assessed by ultrasound measurements in vivo of aortic lumens and by computer-assisted morphometric analyses ex vivo of external diameter. Results from gene expression profiling indicated that the expression of specific matrix metalloproteinases and inflammatory mediators was blunted in aortas from GX DKO mice compared to apoE−/− mice after 10-day Ang II infusion. Ang II induction of cyclooxygenase-2, interleukin-6, matrix metalloproteinase (MMP)-2, MMP-13 and MMP-14 was reduced significantly in GX DKO mice compared to apoE−/− mice. Conclusion GX sPLA2 promotes Ang II-induced pathological responses leading to AAA formation. PMID:20833395

  1. Adenoviruses-mediated RNA interference targeting cytosolic phospholipase A2α attenuates focal ischemic brain damage in mice.

    PubMed

    Wu, Huijun; Liu, Hui; Zuo, Fengtong; Zhang, Lihua

    2018-04-01

    Cerebral ischemia injury is a clinical, frequently occurring disease, which causes a heavy burden on society and families. It has been demonstrated that cytosolic phospholipase A2α (cPLA2α) is significant in neurological injury caused by ischemic brain injury, and inhibition of cPLA2α may reduce stroke injury. In the present study, the role of cPLA2α was investigated in a mouse model of middle cerebral artery occlusion and/or reperfusion (MCAO/R) using an effective cPLA2α inhibitor and adenoviruses‑mediated RNA interference. The most effective recombinant adenovirus encoding cPLA2α small interfering RNA (pAd‑siRNA‑cPLA2α) was constructed and selected. MCAO/R surgery is used to construct the model of focal ischemic brain damage in mice. Adenoviruses‑mediated RNA interference targeting cPLA2α was administered by stereotactic surgery 2 h before the MCAO/R. The expression/activity of cPLA2α and cPLA2α‑derived injurious lipid mediators was assessed. pAd‑siRNA‑cPLA2α‑treated animals (RNA interference; RNAi group) were compared with pAd-siRNA-control-treated animals (negative group) with regard to neurological deficit, motor function, pathological changes, apoptosis, and infarct volume. The RNAi group animals reduced the expression level of cPLA2α, as determined by western blotting and reverse transcription‑quantitative polymerase chain reaction, the improvement of locomotor function was evaluated by rotarod test, and the decrease of apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end‑labeling staining. The decreased infarct areas were evaluated by 2,3,5‑triphenyltetrazolium chloride staining. The expression levels of prostaglandin E2, leukotrienes B4, lysophosphatidylcholine and free fatty acids were reduced in the RNAi group when compared with the negative control group. Thus, the data indicates that the expression level of cPLA2α was effectively controlled by pAd‑siRNA‑cPLA2α treatment. p

  2. Cardiac‐Restricted Overexpression of the A2A‐Adenosine Receptor in FVB Mice Transiently Increases Contractile Performance and Rescues the Heart Failure Phenotype in Mice Overexpressing the A1‐Adenosine Receptor

    PubMed Central

    Chan, Tung O.; Funakoshi, Hajime; Song, Jianliang; Zhang, Xue‐Qian; Wang, JuFang; Chung, Paul H.; DeGeorge, Jr, Brent R.; Li, Xue; Zhang, Jin; Herrmann, David E.; Diamond, Maura; Hamad, Eman; Houser, Steven R.; Koch, Walter J.; Cheung, Joseph Y.; Feldman, Arthur M.

    2008-01-01

    Abstract In the heart, adenosine binds to pharmacologically distinct G‐protein‐coupled receptors (A1‐R, A2A‐R, and A3‐R). While the role of A1‐and A3‐Rs in the heart has been clarifed, the effect of genetically manipulating the A2A‐R has not been defned. Thus, we created mice overexpressing a cardiac‐restricted A2A‐R transgene. Mice with both low (Lo) and high (Hi) levels of A2A‐R overexpression demonstrated an increase in cardiac contractility at 12 weeks. These changes were associated with a signifcantly higher systolic but not diastolic [Ca2+]i, higher maximal contraction amplitudes, and a signifcantly enhanced sarcoplasmic reticulum Ca2+ uptake activity. At 20 weeks, the effects of A2A‐R overexpression on cardiac contractility diminished. The positive effects elicited by A2A‐R overexpression differ from the heart failure phenotype we observed with A1‐R overexpresson. Interestingly, coexpression of A2A‐R TGHi, but not A2A‐R TGLo, enhanced survival, prevented the development of left ventricular dysfunction and heart failure, and improved Ca2+ handling in mice overexpressing the A1‐R. These results suggest that adenosine‐mediated signaling in the heart requires a balance between A1‐ and A2A‐Rs—a fnding that may have important implications for the ongoing clinical evaluation of adenosine receptor subtype‐specifc agonists and antagonists for the treatment of cardiovascular diseases. PMID:20354569

  3. Reduced response to the formalin test and lowered spinal NMDA glutamate receptor binding in adenosine A2A receptor knockout mice.

    PubMed

    Hussey, Martin J; Clarke, Geoffrey D; Ledent, Catherine; Hourani, Susanna M O; Kitchen, Ian

    2007-06-01

    Adenosine is a neuromodulator with complex effects on pain pathways. Mice lacking the adenosine A2A receptor are hypoalgesic, and have altered analgesic responses to receptor-selective opioid agonists. These and other findings suggest a role for the adenosine A2A receptor in sensitizing afferent fibres projecting to the spinal cord. To test this hypothesis formalin (20 microl, 5%) was injected into the paw and nociceptive responses were measured in wildtype and adenosine A2A receptor knockout mice. There was a significant reduction in nociception associated with sensory nerve activation in the knockout mice as measured by time spent biting/licking the formalin-injected paw and number of flinches seen during the first phase, but only the number of flinches was reduced during the second inflammatory phase. In addition, the selective adenosine A2A antagonist SCH58261 (3 and 10 mg/kg) also antagonised both phases of the formalin test. We also labelled NMDA glutamate and NK1 receptors in spinal cord sections as an indirect measure of nociceptive transmission from peripheral sites to the spinal cord. [3H]-Substance P binding to NK1 receptors was unaltered but there was a substantial reduction in binding of [3H]-MK801 to NMDA glutamate receptors in all regions of the spinal cord from knockout mice. The decrease in NMDA glutamate receptor binding may reflect reduced peripheral sensory input to the spinal cord during development and could relate to the hypoalgesia in this genotype. These results support a key role for the adenosine A2A receptor in peripheral nociceptive pathways.

  4. COMPARISON OF OVERALL METABOLISM OF 1, 2, 7, 8-PECDD IN CYP1A2(-L-) KNOCKOUT AND C57BL/6N PARENTAL STRAINS OF MICE

    EPA Science Inventory

    COMPARISON OF OVERALL METABOLISM OF 1,2,3,7,8-PeCDD
    IN CYP1A2 (-/-) KNOCKOUT AND C57BL/6N PARENTAL
    STRAINS OF MICE

    Heldur Hakk1 and Janet J. Diliberto2

    1 USDA-ARS, Biosciences Research Laboratory, P.O. Box 5674, Fargo, ND, USA
    2 US EPA, ORD, National Heal...

  5. Ethanol and 4-methylpyrazole increase DNA adduct formation of furfuryl alcohol in FVB/N wild-type mice and in mice expressing human sulfotransferases 1A1/1A2.

    PubMed

    Sachse, Benjamin; Meinl, Walter; Glatt, Hansruedi; Monien, Bernhard H

    2016-03-01

    Furfuryl alcohol (FFA) is a carcinogenic food contaminant, which is formed by acid- and heat-catalyzed degradation of fructose and glucose. The activation by sulfotransferases (SULTs) yields a DNA reactive and mutagenic sulfate ester. The most prominent DNA adduct, N(2)-((furan-2-yl)methyl)-2'-deoxyguanosine (N(2)-MF-dG), was detected in FFA-treated mice and also in human tissue samples. The dominant pathway of FFA detoxification is the oxidation via alcohol dehydrogenases (ADHs) and aldehyde dehydrogenases (ALDHs). The activity of these enzymes may be greatly altered in the presence of inhibitors or competitive substrates. Here, we investigated the impact of ethanol and the ADH inhibitor 4-methylpyrazole (4MP) on the DNA adduct formation by FFA in wild-type and in humanized mice that were transgenic for human SULT1A1/1A2 and deficient in the mouse (m) Sult1a1 and Sult1d1 genes (h1A1/1A2/1a1(-)/1d1(-)). The administration of FFA alone led to hepatic adduct levels of 4.5 N(2)-MF-dG/10(8) nucleosides and 33.6 N(2)-MF-dG/10(8) nucleosides in male and female wild-type mice, respectively, and of 19.6 N(2)-MF-dG/10(8) nucleosides and 95.4 N(2)-MF-dG/10(8) nucleosides in male and female h1A1/1A2/1a1(-)/1d1(-) mice. The coadministration of 1.6g ethanol/kg body weight increased N(2)-MF-dG levels by 2.3-fold in male and by 1.7-fold in female wild-type mice and by 2.5-fold in male and by 1.5-fold in female h1A1/1A2/1a1(-)/1d1(-) mice. The coadministration of 100mg 4MP/kg body weight had a similar effect on the adduct levels. These findings indicate that modulators of the oxidative metabolism, e.g. the drug 4MP or consumption of alcoholic beverages, may increase the genotoxic effects of FFA also in humans. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Diet-induced obese mice retain endogenous leptin action.

    PubMed

    Ottaway, Nickki; Mahbod, Parinaz; Rivero, Belen; Norman, Lee Ann; Gertler, Arieh; D'Alessio, David A; Perez-Tilve, Diego

    2015-06-02

    Obesity is characterized by hyperleptinemia and decreased response to exogenous leptin. This has been widely attributed to the development of leptin resistance, a state of impaired leptin signaling proposed to contribute to the development and persistence of obesity. To directly determine endogenous leptin activity in obesity, we treated lean and obese mice with a leptin receptor antagonist. The antagonist increased feeding and body weight (BW) in lean mice, but not in obese models of leptin, leptin receptor, or melanocortin-4 receptor deficiency. In contrast, the antagonist increased feeding and BW comparably in lean and diet-induced obese (DIO) mice, an increase associated with decreased hypothalamic expression of Socs3, a primary target of leptin. These findings demonstrate that hyperleptinemic DIO mice retain leptin suppression of feeding comparable to lean mice and counter the view that resistance to endogenous leptin contributes to the persistence of DIO in mice. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Inhibition of secretory phospholipase A2 activity attenuates acute cardiogenic pulmonary edema induced by isoproterenol infusion in mice after myocardial infarction.

    PubMed

    Kawabata, Kenichi; Fujioka, Daisuke; Kobayashi, Tsuyoshi; Saito, Yukio; Obata, Jun-Ei; Nakamura, Takamitsu; Yano, Toshiaki; Watanabe, Kazuhiro; Watanabe, Yosuke; Mishina, Hideto; Kugiyama, Kiyotaka

    2010-10-01

    Several types of secretory phospholipase A2 (sPLA2) are expressed in lung tissue, yielding various eicosanoids that might cause pulmonary edema. This study examined whether inhibition of sPLA2 activity attenuates acute cardiogenic pulmonary edema in mice. Acute cardiogenic pulmonary edema was induced in C57BL/6J male mice by an increase in heart rate with continuous intravenous infusion of isoproterenol (ISP) (10 mg/kg/h) at 2 weeks after the creation of myocardial infarction by left coronary artery ligation. Just before ISP infusion, a single intraperitoneal injection of 100 mg/kg LY374388, a prodrug of LY329722 that inhibits sPLA2 activity, or vehicle was administered. The ISP infusion after myocardial infarction induced interstitial and alveolar edema on lung histology. Furthermore, it increased the lung-to-body weight ratio, pulmonary vascular permeability evaluated by the Evans blue extravasation method, lung activity of sPLA2, and lung content of thromboxane A2 and leukotriene B4. These changes were significantly attenuated by LY374388 treatment. In Kaplan-Meier analysis, the survival rate during the ISP infusion after myocardial infarction was significantly higher in LY374388- than in vehicle-treated mice. Similar results were obtained with another inhibitor of sPLA2 activity, para-bromophenacyl bromide. In conclusion, inhibition of sPLA2 activity suppressed acute cardiogenic pulmonary edema.

  8. Anti-inflammatory effects of inosine in allergic lung inflammation in mice: evidence for the participation of adenosine A2A and A 3 receptors.

    PubMed

    da Rocha Lapa, Fernanda; de Oliveira, Ana Paula Ligeiro; Accetturi, Beatriz Golega; de Oliveira Martins, Isabelli; Domingos, Helory Vanni; de Almeida Cabrini, Daniela; de Lima, Wothan Tavares; Santos, Adair Roberto Soares

    2013-09-01

    Inosine, a naturally occurring purine formed from the breakdown of adenosine, is associated with immunoregulatory effects. Evidence shows that inosine modulates lung inflammation and regulates cytokine generation. However, its role in controlling allergen-induced lung inflammation has yet to be identified. In this study, we aimed to investigate the role of inosine and adenosine receptors in a murine model of lung allergy induced by ovalbumin (OVA). Intraperitoneal administration of inosine (0.001-10 mg/kg, 30 min before OVA challenge) significantly reduced the number of leukocytes, macrophages, lymphocytes and eosinophils recovered in the bronchoalveolar lavage fluid of sensitized mice compared with controls. Interestingly, our results showed that pre-treatment with the selective A2A receptor antagonist (ZM241385), but not with the selective A2B receptor antagonist (alloxazine), reduced the inhibitory effects of inosine against macrophage count, suggesting that A2A receptors mediate monocyte recruitment into the lungs. In addition, the pre-treatment of mice with selective A3 antagonist (MRS3777) also prevented inosine effects against macrophages, lymphocytes and eosinophils. Histological analysis confirmed the effects of inosine and A2A adenosine receptors on cell recruitment and demonstrated that the treatment with ZM241385 and alloxazine reverted inosine effects against mast cell migration into the lungs. Accordingly, the treatment with inosine reduced lung elastance, an effect related to A2 receptors. Moreover, inosine reduced the levels of Th2-cytokines, interleukin-4 and interleukin-5, an effect that was not reversed by A2A or A2B selective antagonists. Our data show that inosine acting on A2A or A3 adenosine receptors can regulate OVA-induced allergic lung inflammation and also implicate inosine as an endogenous modulator of inflammatory processes observed in the lungs of asthmatic patients.

  9. Bee Venom Phospholipase A2 Ameliorates House Dust Mite Extract Induced Atopic Dermatitis Like Skin Lesions in Mice.

    PubMed

    Jung, Kyung-Hwa; Baek, Hyunjung; Kang, Manho; Kim, Namsik; Lee, Seung Young; Bae, Hyunsu

    2017-02-18

    Atopic dermatitis (AD) is a biphasic inflammatory skin disease that is provoked by epidermal barrier defects, immune dysregulation, and increased skin infections. Previously, we have demonstrated that bvPLA2 evoked immune tolerance by inducing regulatory T cells (Treg), and thus alleviated Th2 dominant allergic asthma in mice. Here, we would like to determine whether treatment with bvPLA2 exacerbates the AD-like allergic inflammations induced by house dust mite extract (DFE) in a murine model. Epidermal thickness, immune cell infiltration, serum immunoglobulin, and cytokines were measured. Ear swelling, skin lesions, and the levels of total serum IgE and Th1/Th2 cytokines were elevated in DFE/DNCB-induced AD mice. Topical application of bvPLA2 elicited significant suppression of the increased AD symptoms, including ear thickness, serum IgE concentration, inflammatory cytokines, and histological changes. Furthermore, bvPLA2 treatment inhibited mast cell infiltration into the ear. On the other hand, Treg cell depletion abolished the anti-atopic effects of bvPLA2, suggesting that the effects of bvPLA2 depend on the existence of Tregs. Taken together, the results revealed that topical exposure to bvPLA2 aggravated atopic skin inflammation, suggesting that bvPLA2 might be a candidate for the treatment of AD.

  10. The Absence of Myocardial Calcium-Independent Phospholipase A2γ Results in Impaired Prostaglandin E2 Production and Decreased Survival in Mice with Acute Trypanosoma cruzi Infection

    PubMed Central

    Eickhoff, Christopher S.; Hoft, Daniel F.; Ford, David A.; Gross, Richard W.; McHowat, Jane

    2013-01-01

    Cardiomyopathy is a serious complication of Chagas' disease, caused by the protozoan parasite Trypanosoma cruzi. The parasite often infects cardiac myocytes, causing the release of inflammatory mediators, including eicosanoids. A recent study from our laboratory demonstrated that calcium-independent phospholipase A2γ (iPLA2γ) accounts for the majority of PLA2 activity in rabbit ventricular myocytes and is responsible for arachidonic acid (AA) and prostaglandin E2 (PGE2) release. Thus, we hypothesized that cardiac iPLA2γ contributes to eicosanoid production in T. cruzi infection. Inhibition of the isoform iPLA2γ or iPLA2β, with the R or S enantiomer of bromoenol lactone (BEL), respectively, demonstrated that iPLA2γ is the predominant isoform in immortalized mouse cardiac myocytes (HL-1 cells). Stimulation of HL-1 cells with thrombin, a serine protease associated with microthrombus formation in Chagas' disease and a known activator of iPLA2, increased AA and PGE2 release, accompanied by platelet-activating factor (PAF) production. Similarly, T. cruzi infection resulted in increased AA and PGE2 release over time that was inhibited by pretreatment with (R)-BEL. Further, T. cruzi-infected iPLA2γ-knockout (KO) mice had lower survival rates and increased tissue parasitism compared to wild-type (WT) mice, suggesting that iPLA2γ-KO mice were more susceptible to infection than WT mice. A significant increase in iPLA2 activity was observed in WT mice following infection, whereas iPLA2γ-KO mice showed no alteration in cardiac iPLA2 activity and produced less PGE2. In summary, these studies demonstrate that T. cruzi infection activates cardiac myocyte iPLA2γ, resulting in increased AA and PGE2 release, mediators that may be essential for host survival during acute infection. Thus, these studies suggest that iPLA2γ plays a cardioprotective role during the acute stage of Chagas' disease. PMID:23429536

  11. Disturbed brain phospholipid and docosahexaenoic acid metabolism in calcium-independent phospholipase A2-VIA (iPLA2β)-knockout mice

    PubMed Central

    Cheon, Yewon; Kim, Hyung-Wook; Igarashi, Miki; Modi, Hiren R.; Chang, Lisa; Ma, Kaizong; Greenstein, Deanna; Wohltmann, Mary; Turk, John; Rapoport, Stanley I; Taha, Ameer Y.

    2012-01-01

    Calcium-independent phospholipase A2 group VIA (iPLA2β) releases docosahexaenoic acid (DHA) from phospholipids in vitro. Mutations in the iPLA2β gene, PLA2G6, are associated with dystonia-parkinsonism and infantile neuroaxonal dystrophy. To understand the role of iPLA2β in brain, we applied our in vivo kinetic method using radiolabeled DHA in 4 to 5-month-old wild type (iPLA2β+/+) and knockout (iPLA2β−/−) mice, and measured brain DHA kinetics, lipid concentrations, and expression of PLA2, cyclooxygenase (COX), and lipoxygenase (LOX) enzymes. Compared to iPLA2β+/+ mice, iPLA2β−/− mice showed decreased rates of incorporation of unesterified DHA in plasma into brain phospholipids, reduced concentration of several fatty acid residues (including DHA) esterified in ethanolamine- and serine-glycerophospholipids, and increased lysophospholipid fatty acid concentrations. DHA turnover rates in brain phospholipids did not differ between genotypes. In iPLA2β−/− mice, brain levels of iPLA2β mRNA, protein, and activity were decreased, as was the iPLA2γ (Group VIB PLA2) mRNA level. Brain levels of secretory sPLA2-V mRNA, protein, and activity and cytosolic cPLA2-IVA mRNA were increased in iPLA2β−/− mice. Levels of COX-1 protein were decreased in brain, while COX-2 protein and mRNA were increased. Levels of 5-, 12-, and 15-LOX proteins did not differ significantly between genotypes. Thus, genetic iPLA2β deficiency in mice is associated with profound reorganization of lipid-metabolizing enzyme expression and of phospholipid fatty acid content of brain (particularly of DHA), which may be relevant to the neurologic abnormalities in humans with iPLA2β mutations. PMID:22349267

  12. Restoration of On-Time Embryo Implantation Corrects the Timing of Parturition in Cytosolic Phospholipase A2 Group IVA Deficient Mice1

    PubMed Central

    Brown, Naoko; Morrow, Jason D.; Slaughter, James C.; Paria, Bibhash C.; Reese, Jeff

    2009-01-01

    Cytosolic phospholipase A2 (cPLA2, PLA2G4A) catalyzes the release of arachidonic acid for prostaglandin synthesis by cyclooxygenase 1 (PTGS1) and cyclooxygenase 2 (PTGS2). Mice with Pla2g4a deficiency have parturition delay and other reproductive deficits, including deferred onset of implantation, crowding of implantation sites, and small litters. In this study, we examined the contribution of PLA2G4A to parturition in mice. Pla2g4a mRNA and protein expression were discretely localized in the term and preterm uterine luminal epithelium and colocalized with Ptgs1, but not Ptgs2, expression. The levels of PGE2, PGF2alpha, 6-keto-PGF1alpha, and TxB2 were significantly decreased in Pla2g4a-null uterine tissues, similar to Ptgs1-null uteri, consistent with predominance of PLA2G4A-PTGS1-mediated prostaglandin synthesis in preparation for murine parturition. Litter size was strongly associated with the timing of parturition in Pla2g4a-null mice but could not fully account for the parturition delay. Pla2g4a-null females that received PGE2 + carbaprostacyclin at the time of implantation delivered earlier (20.5 ± 0.2 days vs. 21.6 ± 0.2 days, P < 0.01), although litter size was not improved (4.6 vs. 4.4 pups per litter, P = 0.6). After correction for small litter size, multivariate analysis indicated that Pla2g4a-null mice given prostaglandin treatment to improve implantation timing had gestational length that was similar to wild-type and Pla2g4a heterozygous mice. These results indicate that, despite specific Pla2g4a expression and function in term gestation uteri, the delayed parturition phenotype in Pla2g4a-null mice is primarily due to deferral of implantation. The role of PLA2G4A in timely parturition appears to be critically related to its actions in early pregnancy. PMID:19684335

  13. Leishmania amazonensis-Induced cAMP Triggered by Adenosine A2B Receptor Is Important to Inhibit Dendritic Cell Activation and Evade Immune Response in Infected Mice

    PubMed Central

    Figueiredo, Amanda Braga; Souza-Testasicca, Míriam Conceição; Mineo, Tiago Wilson Patriarca; Afonso, Luís Carlos Crocco

    2017-01-01

    Differently from others Leishmania species, infection by the protozoan parasite L. amazonensis is associated with a lack of antigen-specific T-cell responses. Dendritic cells (DC) are essential for the innate immune response and for directing the differentiation of T-helper lymphocytes. Previously, we showed that L. amazonensis infection impairs DC activation through the activation of adenosine A2B receptor, and here, we evaluated the intracellular events triggered by this receptor in infected cells. To this aim, bone marrow-derived DC from C57BL/6J mice were infected with metacyclic promastigotes of L. amazonensis. Our results show, for the first time, that L. amazonensis increases the production of cAMP and the phosphorylation of extracellular signal-regulated protein kinases 1/2 (ERK1/2) in infected DC by a mechanism dependent on the A2B receptor. Furthermore, L. amazonensis impairs CD40 expression and IL-12 production by DC, and the inhibition of adenylate cyclase, phosphoinositide 3-kinase (PI3K), and ERK1/2 prevent these effects. The increase of ERK1/2 phosphorylation and the inhibition of DC activation by L. amazonensis are independent of protein kinase A (PKA). In addition, C57BL/6J mice were inoculated in the ears with metacyclic promastigotes, in the presence of PSB1115, an A2B receptor antagonist. PSB1115 treatment increases the percentage of CD40+ DC on ears and draining lymph nodes. Furthermore, this treatment reduces lesion size and tissue parasitism. Lymph node cells from treated mice produce higher levels of IFN-γ than control mice, without altering the production of IL-10. In conclusion, we suggest a new pathway used by the parasite (A2B receptor → cAMP → PI3K → ERK1/2) to suppress DC activation, which may contribute to the decrease of IFN-γ production following by the deficiency in immune response characteristic of L. amazonensis infection. PMID:28791011

  14. Leishmania amazonensis-Induced cAMP Triggered by Adenosine A2B Receptor Is Important to Inhibit Dendritic Cell Activation and Evade Immune Response in Infected Mice.

    PubMed

    Figueiredo, Amanda Braga; Souza-Testasicca, Míriam Conceição; Mineo, Tiago Wilson Patriarca; Afonso, Luís Carlos Crocco

    2017-01-01

    Differently from others Leishmania species, infection by the protozoan parasite L. amazonensis is associated with a lack of antigen-specific T-cell responses. Dendritic cells (DC) are essential for the innate immune response and for directing the differentiation of T-helper lymphocytes. Previously, we showed that L. amazonensis infection impairs DC activation through the activation of adenosine A 2B receptor, and here, we evaluated the intracellular events triggered by this receptor in infected cells. To this aim, bone marrow-derived DC from C57BL/6J mice were infected with metacyclic promastigotes of L. amazonensis . Our results show, for the first time, that L. amazonensis increases the production of cAMP and the phosphorylation of extracellular signal-regulated protein kinases 1/2 (ERK1/2) in infected DC by a mechanism dependent on the A 2B receptor. Furthermore, L. amazonensis impairs CD40 expression and IL-12 production by DC, and the inhibition of adenylate cyclase, phosphoinositide 3-kinase (PI3K), and ERK1/2 prevent these effects. The increase of ERK1/2 phosphorylation and the inhibition of DC activation by L. amazonensis are independent of protein kinase A (PKA). In addition, C57BL/6J mice were inoculated in the ears with metacyclic promastigotes, in the presence of PSB1115, an A 2B receptor antagonist. PSB1115 treatment increases the percentage of CD40 + DC on ears and draining lymph nodes. Furthermore, this treatment reduces lesion size and tissue parasitism. Lymph node cells from treated mice produce higher levels of IFN-γ than control mice, without altering the production of IL-10. In conclusion, we suggest a new pathway used by the parasite (A 2B receptor → cAMP → PI3K → ERK1/2) to suppress DC activation, which may contribute to the decrease of IFN-γ production following by the deficiency in immune response characteristic of L. amazonensis infection.

  15. Low-density lipoprotein from apolipoprotein E-deficient mice induces macrophage lipid accumulation in a CD36 and scavenger receptor class A-dependent manner.

    PubMed

    Zhao, Zhenze; de Beer, Maria C; Cai, Lei; Asmis, Reto; de Beer, Frederick C; de Villiers, Willem J S; van der Westhuyzen, Deneys R

    2005-01-01

    To investigate the potential of circulating low-density lipoprotein (LDL), isolated from apolipoprotein E (apoE)-deficient mice (E-/-LDL) and from LDL receptor-deficient mice (Lr-/-LDL), to induce foam cell formation. Binding studies using COS-7 cells overexpressing CD36, J774 cells, and mouse peritoneal macrophages (MPMs) unexpectedly showed for the first time that E-/-LDL, which is enriched in cholesterol, is a high-affinity ligand for CD36 and exhibited greater macrophage uptake than Lr-/-LDL or normal LDL. Minimal copper-mediated oxidization of Lr-/-LDL or C57LDL in vitro resulted in increased ligand internalization, although cell uptake of these oxidized LDLs was lower than that of E-/-LDL, even at oxidation levels similar to that found in E-/-LDL. Treatment of MPMs with E-/-LDL and Lr-/-LDL (to a 2- to 3-fold lesser extent), but not normal LDL, resulted in significant cellular cholesteryl ester accumulation and foam cell formation. Experiments using MPMs lacking CD36, scavenger receptor class A (SR-A), or both, indicated a major contribution of CD36 ( approximately 50%), and to a lesser extent, SR-A (24% to 30%), to E-/-LDL uptake. Because of its increased state of oxidation and high cholesterol content, LDL in apoE-deficient mice acts in a proatherogenic manner, without requiring further modification in the vascular wall, to induce foam cell formation through its uptake by scavenger receptors.

  16. Inosine reduces pain-related behavior in mice: involvement of adenosine A1 and A2A receptor subtypes and protein kinase C pathways.

    PubMed

    Nascimento, Francisney P; Figueredo, Sonia M; Marcon, Rodrigo; Martins, Daniel F; Macedo, Sérgio J; Lima, Denise A N; Almeida, Rúbia C; Ostroski, Rosana M; Rodrigues, Ana Lúcia S; Santos, Adair Roberto Soares

    2010-08-01

    Inosine, an endogenous purine, is the first metabolite of adenosine in a reaction catalyzed by adenosine deaminase. This study aimed to investigate the antinociceptive effects of inosine against several models of pain in mice and rats. In mice, inosine given by systemic or central routes inhibited acetic acid-induced nociception. Furthermore, inosine also decreased the late phase of formalin-induced licking and the nociception induced by glutamate. Inosine produced inhibition (for up to 4 h) of mechanical allodynia induced by complete Freund's adjuvant (CFA) injected into the mouse's paw. Given chronically for 21 days, inosine reversed the mechanical allodynia caused by CFA. Moreover, inosine also reduced the thermal (cold stimuli) and mechanical allodynia caused by partial sciatic nerve ligation (PSNL) for 4 h; when inosine was chronically administered, it decreased the mechanical allodynia induced by PSNL for 22 days. Antinociception caused by inosine in the acetic acid test was attenuated by treatment of mice with 1,3-dipropyl-8-cyclopentylxanthine (DPCPX; a selective adenosine A(1) receptor antagonist), 8-phenyltheophylline (8-PT; a nonselective adenosine A(1) receptor antagonist), and 4-{2- [7-amino-2-(2-furyl)[1,2,4]triazolo-[2,3-a][1,3,5]triazin-5-yl- amino]ethyl}phenol (ZM241385; a selective adenosine A(2A) receptor antagonist). In rats, inosine inhibited the mechanical and heat hyperalgesia induced by bradykinin and phorbol 12-myristate 13-acetate, without affecting similar responses caused by prostaglandin E(2) or forskolin. These results indicate that inosine induces antinociceptive, antiallodynic, and antihyperalgesic effects in rodents. The precise mechanisms through which inosine produces antinociception are currently under investigation, but involvement of adenosine A(1) and A(2A) receptors and blockade of the protein kinase C pathway seem to largely account for inosine's antinociceptive effect.

  17. In vitro characterization of T-type calcium channel antagonist TTA-A2 and in vivo effects on arousal in mice.

    PubMed

    Kraus, Richard L; Li, Yuxing; Gregan, Yun; Gotter, Anthony L; Uebele, Victor N; Fox, Steven V; Doran, Scott M; Barrow, James C; Yang, Zhi-Qiang; Reger, Thomas S; Koblan, Kenneth S; Renger, John J

    2010-11-01

    T-type calcium channels have been implicated in many behaviorally important neurophysiological processes, and altered channel activity has been linked to the pathophysiology of neurological disorders such as insomnia, epilepsy, Parkinson's disease, depression, schizophrenia, and pain. We have previously identified a number of potent and selective T-type channel antagonists (Barrow et al., 2007; Shipe et al., 2008; Yang et al., 2008). Here we describe the properties of the antagonist TTA-A2 [2-(4-cyclopropylphenyl)-N-((1R)-1-{5-[(2,2,2-trifluoroethyl)oxo]-pyridin-2-yl}ethyl)acetamide], assessed in patch-clamp experiments. TTA-A2 blocks T-type channels (Ca(v)3.1, 3.2, 3.3) voltage dependently and with high potency (IC(50) ∼100 nM). Stimulation at 3 Hz revealed additional use dependence of inhibition. A hyperpolarized shift of the channel availability curve and delayed channel recovery from inactivation suggest that the compound preferentially interacts with and stabilizes inactivated channels. The compound showed a ∼300-fold selectivity for Ca(v)3 channels over high-voltage activated calcium channels. Inhibitory effects on native T-type currents were confirmed in brain slice recordings from the dorsal lateral geniculate nucleus and the subthalamic nucleus. Furthermore, we demonstrate that in vivo T-type channel inhibition by TTA-A2 suppresses active wake and promotes slow-wave sleep in wild-type mice but not in mice lacking both Ca(v)3.1 and Ca(v)3.3, suggesting the selective effect of TTA-A2 on recurrent thalamocortical network activity. The discovery of the potent and selective T-type channel antagonist TTA-A2 has enabled us to study the in vivo effects of pharmacological T-channel inhibition on arousal in mice, and it will help to explore the validity of these channels as potential drug targets for sleep-related and other neurological diseases.

  18. Immunotoxicity and biodistribution analysis of arsenic trioxide in C57Bl/6 mice following a 2-week inhalation exposure

    SciTech Connect

    Burchiel, Scott W., E-mail: Sburchiel@salud.unm.ed; Mitchell, Leah A.; Lauer, Fredine T.

    2009-12-15

    In these studies the immunotoxicity of arsenic trioxide (ATO, As{sub 2}O{sub 3}) was evaluated in mice following 14 days of inhalation exposures (nose only, 3 h per day) at concentrations of 50 mug/m{sup 3} and 1 mg/m{sup 3}. A biodistribution analysis performed immediately after inhalation exposures revealed highest levels of arsenic in the kidneys, bladder, liver, and lung. Spleen cell levels were comparable to those found in the blood, with the highest concentration of arsenic detected in the spleen being 150 mug/g tissue following the 1 mg/m{sup 3} exposures. No spleen cell cytotoxicity was observed at either of the twomore » exposure levels. There were no changes in spleen cell surface marker expression for B cells, T cells, macrophages, and natural killer (NK) cells. There were also no changes detected in the B cell (LPS-stimulated) and T cell (Con A-stimulated) proliferative responses of spleen cells, and no changes were found in the NK-mediated lysis of Yac-1 target cells. The primary T-dependent antibody response was, however, found to be highly susceptible to ATO suppression. Both the 50 mug/m{sup 3} and 1 mg/m{sup 3} exposures produced greater than 70% suppression of the humoral immune response to sheep red blood cells. Thus, the primary finding of this study is that the T-dependent humoral immune response is extremely sensitive to suppression by ATO and assessment of humoral immune responses should be considered in evaluating the health effects of arsenic containing agents.« less

  19. In Utero and Lactational Exposure to PCBs in Mice: Adult Offspring Show Altered Learning and Memory Depending on Cyp1a2 and Ahr Genotypes

    PubMed Central

    Curran, Christine P.; Genter, Mary Beth; Patel, Krishna V.; Schaefer, Tori L.; Skelton, Matthew R.; Williams, Michael T.; Vorhees, Charles V.

    2011-01-01

    Background: Both coplanar and noncoplanar polychlorinated biphenyls (PCBs) exhibit neurotoxic effects in animal studies, but individual congeners do not always produce the same effects as PCB mixtures. Humans genetically have > 60-fold differences in hepatic cytochrome P450 1A2 (CYP1A2)-uninduced basal levels and > 12-fold variability in aryl hydrocarbon receptor (AHR)affinity; because CYP1A2 is known to sequester coplanar PCBs and because AHR ligands include coplanar PCBs, both genotypes can affect PCB response. Objectives: We aimed to develop a mouse paradigm with extremes in Cyp1a2 and Ahr genotypes to explore genetic susceptibility to PCB-induced developmental neurotoxicity using an environmentally relevant mixture of PCBs. Methods: We developed a mixture of eight PCBs to simulate human exposures based on their reported concentrations in human tissue, breast milk, and food supply. We previously characterized specific differences in PCB congener pharmacokinetics and toxicity, comparing high-affinity–AHR Cyp1a2 wild-type [Ahrb1_Cyp1a2(+/+)], poor-affinity–AHR Cyp1a2 wild-type [Ahrd_Cyp1a2(+/+)], and high-affinity–AHR Cyp1a2 knockout [Ahrb1_Cyp1a2(–/–)] mouse lines [Curran CP, Vorhees CV, Williams MT, Genter MB, Miller ML, Nebert DW. 2011. In utero and lactational exposure to a complex mixture of polychlorinated biphenyls: toxicity in pups dependent on the Cyp1a2 and Ahr genotypes. Toxicol Sci 119:189–208]. Dams received a mixture of three coplanar and five noncoplanar PCBs on gestational day 10.5 and postnatal day (PND) 5. In the present study we conducted behavioral phenotyping of exposed offspring at PND60, examining multiple measures of learning, memory, and other behaviors. Results: We observed the most significant deficits in response to PCB treatment in Ahrb1_Cyp1a2(–/–) mice, including impaired novel object recognition and increased failure rate in the Morris water maze. However, all PCB-treated genotypes showed significant differences on

  20. Evaluation of antidepressant-like and anxiolytic-like activity of purinedione-derivatives with affinity for adenosine A2A receptors in mice.

    PubMed

    Dziubina, Anna; Szmyd, Karina; Zygmunt, Małgorzata; Sapa, Jacek; Dudek, Magdalena; Filipek, Barbara; Drabczyńska, Anna; Załuski, Michał; Pytka, Karolina; Kieć-Kononowicz, Katarzyna

    2016-12-01

    It has recently been suggested that the adenosine A 2A receptor plays a role in several animal models of depression. Additionally, A 2A antagonists have reversed behavioral deficits and exhibited a profile similar to classical antidepressants. In the present study, imidazo- and pyrimido[2,1-f]purinedione derivatives (KD 66, KD 167, KD 206) with affinity to A 2A receptors but poor A 1 affinity were evaluated for their antidepressant- and anxiolytic-like activity. The activity of these derivatives was tested using a tail suspension and forced swim test, two widely-used behavioral paradigms for the evaluation of antidepressant-like activity. In turn, the anxiolytic activity was evaluated using the four-plate test. The results showed the antidepressant-like activity of pyrimido- and imidazopurinedione derivatives (i.e. KD 66, KD 167 and KD 206) in acute and chronic behavioral tests in mice. KD 66 revealed an anxiolytic-like effect, while KD 167 increased anxiety behaviors. KD 206 had no effect on anxiety. Furthermore, none of the tested compounds increased locomotor activity. Available data support the proposition that the examined compounds with adenosine A 2A receptor affinity may be an interesting target for the development of antidepressant and/or anxiolytic agents. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  1. Attenuation of nicotine's discriminative stimulus effects in rats and its locomotor activity effects in mice by serotonergic 5-HT2A/2C receptor agonists.

    PubMed

    Batman, Angela M; Munzar, Patrik; Beardsley, Patrick M

    2005-05-01

    Reports have indicated that administration of nicotine inhibits, while withdrawal of chronically administered nicotine augments effects of serotonergic 5HT2A/2C agonists. It was our objective to determine whether 5HT2A/2C agonists can modulate the discriminative stimulus effects of nicotine in rats or its locomotor activity effects in mice. Adult male Sprague-Dawley rats were trained to discriminate 0.3 mg/kg nicotine base from saline in a two-lever, fixed-ratio (FR10), food-reinforced, operant-conditioning task during daily (Monday-Friday) 15-min experimental sessions. After characterizing a dose-response curve for nicotine, we tested the ability of the 5HT(2A/2C) agonists (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane HCL (DOI; 0.18-1.0 mg/kg) and 1-(4-bromo-2, 5-dimethoxyphenyl)-2-aminopropane (DOB; 0.1-1.0 mg/kg), the 5HT2C agonist 6-chloro-2-(1-piperazinyl)pyrazine hydrochloride (MK 212; 0.1 mg/kg-1.0 mg/kg), and the 5HT1A agonist (+/-)-8-hydroxy-2-(di-n-propylamino)tetralin hydrobromide (8-OH-DPAT; 0.01 mg/kg-1.0 mg/kg) to modulate nicotine's discriminative stimulus effects. After finding that DOI was able to attenuate the percentage nicotine lever responding (%NLR), we tested for it to also reverse nicotine's effects on locomotor activity in mice. The 5HT2A/2C agonists-in particular DOI-dose dependently attenuated %NLR. The effects of DOI were reversed by the 5HT2A/2C antagonist ketanserin. MK 212 and 8-OH-DPAT had irregular effects among rats and only reduced %NLR to below 50% levels at doses markedly suppressing responding. DOI also dose dependently blocked nicotine's acute rate-lowering locomotor activity effects. These results indicate that activation of serotonin 5HT2A/2C receptors can blunt the discriminative stimulus and locomotor activity effects of nicotine and presents the possibility that activation of these receptors might also be able to attenuate other effects of nicotine.

  2. Both MC5r and A2Ar are required for protective regulatory immunity in the spleen of post-experimental autoimmune uveitis in mice

    PubMed Central

    Lee, Darren J.; Taylor, Andrew W.

    2013-01-01

    The ocular microenvironment uses a poorly defined melanocortin 5 receptor (MC5r)-dependent pathway to recover immune tolerance following intraocular inflammation. This dependency is seen in experimental autoimmune uveoretinitis (EAU), a mouse model of endogenous human autoimmune uveitis, with the emergence of autoantigen-specific regulatory immunity in the spleen that protects the mice from recurrence of EAU. In this new study, it was found that the MC5r-dependent regulatory immunity was an increase of CD11b+ F4/80+ Ly-6Clow Ly-6G+ CD39+ CD73+ APC in the spleen of post-EAU mice. These MC5r-dependent APC require adenosine 2A receptor (A2Ar) expression on T cells to activate EAU-suppressing CD25+ CD4+ FoxP3+ Treg cells. Therefore, in the recovery from autoimmune disease the ocular microenvironment induces tolerance through a melanocortin mediated expansion of Ly-6G+ regulatory APC in the spleen that utilize the adenosinergic pathway to promote activation of autoantigen-specific Treg cells. PMID:24043903

  3. Role of Genetic Background in Determining Phenotypic Severity Throughout Postnatal Development and at Peak Bone Mass in Col1a2 Deficient Mice (oim)

    PubMed Central

    Carleton, Stephanie M.; McBride, Daniel J.; Carson, William L.; Huntington, Carolyn E.; Twenter, Kristin L.; Rolwes, Kristin M.; Winkelmann, Christopher T.; Morris, J. Steve; Taylor, Jeremy F.; Phillips, Charlotte L.

    2008-01-01

    Osteogenesis imperfecta (OI) is a genetically and clinically heterogeneous disease characterized by extreme bone fragility. Although fracture numbers tend to decrease post-puberty, OI patients can exhibit significant variation in clinical outcome, even among related individuals harboring the same mutation. OI most frequently results from mutations in type I collagen genes, yet how genetic background impacts phenotypic outcome remains unclear. Therefore, we analyzed the phenotypic severity of a known proα2(I) collagen gene defect (oim) on two genetic backgrounds (congenic C57BL/6J and outbred B6C3Fe) throughout postnatal development to discern the phenotypic contributions of the Col1a2 locus relative to the contribution of the genetic background. To this end, femora and tibiae were isolated from wildtype (Wt) and homozygous (oim/oim) mice of each strain at 1, 2 and 4 months of age. Femoral geometry was determined via µCT prior to torsional loading to failure to assess bone structural and material biomechanical properties. Changes in mineral composition, collagen content and bone turnover were determined using neutron activation analyses, hydroxyproline content and serum pyridinoline crosslinks. µCT analysis demonstrated genotype-, strain- and age-associated changes in femoral geometry as well as a marked decrease in the amount of bone in oim/oim mice of both strains. Oim/oim mice of both strains, as well as C57BL/6J (B6) mice of all genotypes, had reduced femoral biomechanical strength properties compared to Wt at all ages, although they improved with age. Mineral levels of fluoride, magnesium and sodium were associated with biomechanical strength properties in both strains and all genotypes at all ages. Oim/oim animals also had reduced collagen content as compared to Wt at all ages. Serum pyridinoline crosslinks were highest at two months of age, regardless of strain or genotype. Strain differences in bone parameters exist throughout development, implicating a

  4. Oral administration of Japanese sake yeast (Saccharomyces cerevisiae sake) promotes non-rapid eye movement sleep in mice via adenosine A2Areceptors.

    PubMed

    Nakamura, Yoshitaka; Midorikawa, Tatsuyuki; Monoi, Noriyuki; Kimura, Eriko; Murata-Matsuno, Ayumi; Sano, Tomomi; Oka, Kengo; Sugafuji, Toshihiro; Uchiyama, Akira; Murakoshi, Michiaki; Sugiyama, Keikichi; Nishino, Hoyoku; Urade, Yoshihiro

    2016-12-01

    We have demonstrated previously that Japanese sake yeast improves sleep quality in humans. In the present study, we examined the molecular mechanisms of sake yeast to induce sleep by monitoring locomotor activity, electromyogram and electroencephalogram in mice. Oral administration of Japanese sake yeast (100, 200, and 300 mg kg -1 ) decreased the locomotor activity by 18, 46 and 59% and increased the amount of non-rapid eye movement (NREM) sleep by 1.5-, 2.3- and 2.4-fold (to 37 ± 6, 57 ± 8, and 60 ± 4 min from 25 ± 6 min in the vehicle-administered group, respectively) in a dose-dependent manner for 4 h after oral administration. However, Japanese sake yeast did not change the amount of rapid eye movement (REM) sleep, the electroencephalogram power density during NREM sleep or show any adverse effects, such as rebound of insomnia, during 24 h postadministration and on the next day. An intraperitoneal pretreatment with an adenosine A 2A receptor-selective antagonist, ZM241385 (15 mg kg -1 ), reduced the amount of NREM sleep of sake yeast-administered mice to the basal level, without changing basal amount of sleep. Conversely, an A 1 receptor-selective antagonist, 8-cyclopentyltheophylline (10 mg kg -1 ), did not affect the sleep-promoting effect of Japanese sake yeast. Thus, Japanese sake yeast promotes NREM sleep via activation of adenosine A 2A but not A 1 receptors. © 2016 European Sleep Research Society.

  5. Relaxation of porcine retinal arterioles exposed to hypercholesterolemia in vivo is modified by hepatic LDL-receptor deficiency and diabetes mellitus.

    PubMed

    Bek, Toke; Al-Mashhadi, Rozh H; Misfeldt, Mikkel; Riis-Vestergaard, Mette Ji; Bentzon, Jacob Fog; Pedersen, Simon Metz Mariendal

    2013-10-01

    the groups. Relaxation of porcine retinal arterioles exposed to hypercholesterolemia in vivo is modified by hepatic LDL-receptor deficiency and diabetes mellitus. This suggests that transgenic animal models are suitable for studying the influence of systemic diseases on retinal vascular function. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Inosine, an Endogenous Purine Nucleoside, Suppresses Immune Responses and Protects Mice from Experimental Autoimmune Encephalomyelitis: a Role for A2A Adenosine Receptor.

    PubMed

    Junqueira, Stella Célio; Dos Santos Coelho, Igor; Lieberknecht, Vicente; Cunha, Mauricio Peña; Calixto, João B; Rodrigues, Ana Lúcia S; Santos, Adair Roberto Soares; Dutra, Rafael Cypriano

    2017-07-01

    Multiple sclerosis (MS) is a T cell autoimmune, inflammatory, and demyelinating disease of the central nervous system (CNS). Currently available therapies have partially effective actions and numerous side reactions. Inosine, an endogenous purine nucleoside, has immunomodulatory, neuroprotective, and analgesic properties. Herein, we evaluated the effect of inosine on the development and progression of experimental autoimmune encephalomyelitis (EAE), an experimental model of MS. Inosine (1 or 10 mg/kg, i.p.) was administrated twice a day for 40 days. Immunological and inflammatory responses were evaluated by behavioral, histological, immunohistochemical, ELISA, RT-PCR, and Western blotting analysis. The administration of inosine exerted neuroprotective effects against EAE by diminishing clinical signs, including thermal and mechanical hyperalgesia, as well as weight loss typical of the disease. These beneficial effects of inosine seem to be associated with the blockade of inflammatory cell entry into the CNS, especially lymphocytes, thus delaying the demyelinating process and astrocytes activation. In particular, up-regulation of IL-17 levels in the secondary lymphoid tissues, a result of EAE, was prevented by inosine treatment in EAE mice. Additionally, inosine consistently prevented A2AR up-regulation in the spinal cord, likely, through an ERK1-independent pathway. Altogether, these results allow us to propose that this endogenous purine might be a putative novel and helpful tool for the prevention of autoimmune and neurodegenerative diseases, such as MS. Thus, inosine could have considerable implications for future therapies of MS, and this study may represent the starting point for further investigation into the role of inosine and adenosinergic receptors in neuroinflammation processes. Graphical Abstract Preventive treatment with inosine inhibits the development and progression of EAE in C57Bl/6 mice. Furthermore, neuroinflammation and demyelinating processes

  7. Polyphenol-enriched Vaccinium uliginosum L. fractions reduce retinal damage induced by blue light in A2E-laden ARPE19 cell cultures and mice.

    PubMed

    Lee, Bom-Lee; Kang, Jung-Hwan; Kim, Hye-Mi; Jeong, Se-Hee; Jang, Dae-Sik; Jang, Young-Pyo; Choung, Se-Young

    2016-12-01

    Polyphenols exert beneficial effects on vision. We hypothesized that polyphenol components of Vaccinium uliginosum L. (V.U.) extract protect retinal pigment epithelial (RPE) cells against blue light-induced damage. Our aim was to test extracts containing polyphenol components to ascertain effects to reduce damage against blue light in RPEs. We measured the activity in fractions eluted from water, ethanol, and HP20 resin (FH), and found that the FH fraction had the highest beneficial activity. We isolated the individual active compounds from the FH fraction using chromatographic techniques, and found that FH contained flavonoids, anthocyanins, phenyl propanoids, and iridoids. Cell cultures of A2E-laden ARPE-19 exposed to blue light after treatment with V.U. extract fractions and their individual constituents indicated improvement. V uliginosum L extract fractions and constituent compounds significantly reduced A2E photo-oxidation-induced RPE cell death and inhibited intracellular A2E accumulation. Furthermore, Balb/c male mice were exposed to blue light at 10000 lux for 1 h/d for 2 weeks to induce retinal damage. One week after the final blue light exposure, retinal damage evaluated revealed that the outer nuclear layer thickness and nuclei count were improved. Histologic examination of murine photoreceptor cells demonstrated that FH, rich in polyphenols, inhibited the loss of outer nuclear layer thickness and nuclei. Our findings suggest that V.U. extract and eluted fractions are a potential source of bioactive compounds that potentially serve a therapeutic approach for age-related macular degeneration. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Genotoxicity of three food processing contaminants in transgenic mice expressing human sulfotransferases 1A1 and 1A2 as assessed by the in vivo alkaline single cell gel electrophoresis assay.

    PubMed

    Høie, Anja Hortemo; Svendsen, Camilla; Brunborg, Gunnar; Glatt, Hansruedi; Alexander, Jan; Meinl, Walter; Husøy, Trine

    2015-10-01

    The food processing contaminants 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 5-hydroxymethylfurfural (HMF) and 2,5 dimethylfuran (DMF) are potentially both mutagenic and carcinogenic in vitro and/or in vivo, although data on DMF is lacking. The PHIP metabolite N-hydroxy-PhIP and HMF are bioactivated by sulfotransferases (SULTs). The substrate specificity and tissue distribution of SULTs differs between species. A single oral dose of PhIP, HMF or DMF was administered to wild-type (wt) mice and mice expressing human SULT1A1/1A2 (hSULT mice). DNA damage was studied using the in vivo alkaline single cell gel electrophoresis (SCGE) assay. No effects were detected in wt mice. In the hSULT mice, PhIP and HMF exposure increased the levels of DNA damage in the liver and kidney, respectively. DMF was not found to be genotoxic. The observation of increased DNA damage in hSULT mice compared with wt mice supports the role of human SULTs in the bioactivation of N-hydroxy-PhIP and HMF in vivo. © 2015 The Authors. Environmental and Molecular Mutagenesis Published by Wiley Periodicals, Inc.

  9. Genotoxicity of three food processing contaminants in transgenic mice expressing human sulfotransferases 1A1 and 1A2 as assessed by the in vivo alkaline single cell gel electrophoresis assay

    PubMed Central

    Høie, Anja Hortemo; Svendsen, Camilla; Brunborg, Gunnar; Glatt, Hansruedi; Alexander, Jan; Meinl, Walter

    2015-01-01

    The food processing contaminants 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP), 5‐hydroxymethylfurfural (HMF) and 2,5 dimethylfuran (DMF) are potentially both mutagenic and carcinogenic in vitro and/or in vivo, although data on DMF is lacking. The PHIP metabolite N‐hydroxy‐PhIP and HMF are bioactivated by sulfotransferases (SULTs). The substrate specificity and tissue distribution of SULTs differs between species. A single oral dose of PhIP, HMF or DMF was administered to wild‐type (wt) mice and mice expressing human SULT1A1/1A2 (hSULT mice). DNA damage was studied using the in vivo alkaline single cell gel electrophoresis (SCGE) assay. No effects were detected in wt mice. In the hSULT mice, PhIP and HMF exposure increased the levels of DNA damage in the liver and kidney, respectively. DMF was not found to be genotoxic. The observation of increased DNA damage in hSULT mice compared with wt mice supports the role of human SULTs in the bioactivation of N‐hydroxy‐PhIP and HMF in vivo. Environ. Mol. Mutagen. 56:709–714, 2015. © 2015 The Authors. Environmental and Molecular Mutagenesis Published by Wiley Periodicals, Inc. PMID:26270892

  10. Regulatory T Cells Contribute to the Inhibition of Radiation-Induced Acute Lung Inflammation via Bee Venom Phospholipase A2 in Mice

    PubMed Central

    Shin, Dasom; Lee, Gihyun; Sohn, Sung-Hwa; Park, Soojin; Jung, Kyung-Hwa; Lee, Ji Min; Yang, Jieun; Cho, Jaeho; Bae, Hyunsu

    2016-01-01

    Bee venom has long been used to treat various inflammatory diseases, such as rheumatoid arthritis and multiple sclerosis. Previously, we reported that bee venom phospholipase A2 (bvPLA2) has an anti-inflammatory effect through the induction of regulatory T cells. Radiotherapy is a common anti-cancer method, but often causes adverse effects, such as inflammation. This study was conducted to evaluate the protective effects of bvPLA2 in radiation-induced acute lung inflammation. Mice were focally irradiated with 75 Gy of X-rays in the lung and administered bvPLA2 six times after radiation. To evaluate the level of inflammation, the number of immune cells, mRNA level of inflammatory cytokine, and histological changes in the lung were measured. BvPLA2 treatment reduced the accumulation of immune cells, such as macrophages, neutrophils, lymphocytes, and eosinophils. In addition, bvPLA2 treatment decreased inflammasome-, chemokine-, cytokine- and fibrosis-related genes’ mRNA expression. The histological results also demonstrated the attenuating effect of bvPLA2 on radiation-induced lung inflammation. Furthermore, regulatory T cell depletion abolished the therapeutic effects of bvPLA2 in radiation-induced pneumonitis, implicating the anti-inflammatory effects of bvPLA2 are dependent upon regulatory T cells. These results support the therapeutic potential of bvPLA2 in radiation pneumonitis and fibrosis treatments. PMID:27144583

  11. Preventive effects of procyanidin A2 on glucose homeostasis, pancreatic and duodenal homebox 1, and glucose transporter 2 gene expression disturbance induced by bisphenol A in male mice.

    PubMed

    Ahangarpour, A; Afshari, G; Mard, S A; Khodadadi, A; Hashemitabar, M

    2016-04-01

    Procyanidins (PCs) as oligomeric compounds with antidiabetic properties formed from catechin and epicatechin molecules. Bisphenol A(BPA) is a common chemical material use in food and beverage packaging. The aim of this study was to explore the protective effects of procyanidin A2 (PCA2) against glucose homeostasis disturbance and gene expression of pancreatic and duodenal homebox 1 (Pdx1) as well as glucose transporter 2 (Glut2) induced by BPA in male mice. First tested these five concentrations of PCA2 (3 - 300 μM) alone and in combination with BPA(100 μg/L), on insulin secretion from isolated islets at in vitro condition. Next, examined the influence of BPA and PCA2 on islet apoptosis using flowcytometry. At in vivo condition, the BPA (100 μg/kg) and PCA2 (10 μmol/kg) administered for 20 days then, blood glucose and insulin, Pdx1 and, Glut2 genes expression, and oxidative stress markers examined. The results indicated that PCA2 strongly prevents islet cells apoptosis induced by BPA and, co-administration of PCA2 and BPA modified hyperglycemia. BPA reduced Pdx1 and Glut2 mRNA expression and antioxidant level in pancreas tissue, whereas PCA2 prevented from these effects. The findings from these studies suggest that use of PCA2 rich plants have preventive effects on hyperglycemia, and type 2 diabetes.

  12. Streptococcus pyogenes Phospholipase A2 Induces the Expression of Adhesion Molecules on Human Umbilical Vein Endothelial Cells and Aorta of Mice.

    PubMed

    Oda, Masataka; Domon, Hisanori; Kurosawa, Mie; Isono, Toshihito; Maekawa, Tomoki; Yamaguchi, Masaya; Kawabata, Shigetada; Terao, Yutaka

    2017-01-01

    The Streptococcus pyogenes phospholipase A 2 (SlaA) gene is highly conserved in the M3 serotype of group A S. pyogenes , which often involves hypervirulent clones. However, the role of SlaA in S. pyogenes pathogenesis is unclear. Herein, we report that SlaA induces the expression of intercellular adhesion molecule 1 (ICAM1) and vascular cell adhesion molecule 1 (VCAM1) via the arachidonic acid signaling cascade. Notably, recombinant SlaA induced ICAM1 and VCAM1 expression in human umbilical vein endothelial cells (HUVECs), resulting in enhanced adhesion of human monocytic leukemia (THP-1) cells. However, C134A, a variant enzyme with no enzymatic activity, did not induce such events. In addition, culture supernatants from S. pyogenes SSI-1 enhanced the adhesion of THP-1 cells to HUVECs, but culture supernatants from the Δ slaA isogenic mutant strain had limited effects. Aspirin, a cyclooxygenase 2 inhibitor, prevented the adhesion of THP-1 cells to HUVECs and did not induce ICAM1 and VCAM1 expression in HUVECs treated with SlaA. However, zileuton, a 5-lipoxygenase inhibitor, did not exhibit such effects. Furthermore, pre-administration of aspirin in mice intravenously injected with SlaA attenuated the transcriptional abundance of ICAM1 and VCAM1 in the aorta. These results suggested that SlaA from S. pyogenes stimulates the expression of adhesion molecules in vascular endothelial cells. Thus, SlaA contributes to the inflammation of vascular endothelial cells upon S. pyogenes infection.

  13. Group V Secretory Phospholipase A2 Enhances the Progression of Angiotensin II–Induced Abdominal Aortic Aneurysms but Confers Protection against Angiotensin II–Induced Cardiac Fibrosis in ApoE-Deficient Mice

    PubMed Central

    Boyanovsky, Boris B.; Bailey, William; Dixon, Lauren; Shridas, Preetha; Webb, Nancy R.

    2013-01-01

    Abdominal aortic aneurysms (AAAs) and heart failure are complex life-threatening diseases whose etiology is not completely understood. In this study, we investigated whether deficiency of group V secretory phospholipase A2 (GV sPLA2) protects from experimental AAA. The impact of GV sPLA2 deficiency on angiotensin (Ang) II–induced cardiac fibrosis was also investigated. Apolipoprotein E (apoE)−/− mice and apoE−/− mice lacking GV sPLA2 (GV DKO) were infused with 1000 ng/kg per minute Ang II for up to 28 days. Increases in systolic blood pressure, plasma aldosterone level, and urinary and heart prostanoids were similar in apoE−/− and GV DKO mice after Ang II infusion. The incidence of aortic rupture in Ang II–infused GV DKO mice (10%) was significantly reduced compared with apoE−/− mice (29.4%). Although the incidence of AAA in GV DKO mice (81.3%) and apoE−/− mice (100%) was similar, the mean percentage increase in maximal luminal diameter of abdominal aortas was significantly smaller in GV DKO mice (68.5% ± 7.7%) compared with apoE−/− mice (92.6% ± 8.3%). Deficiency of GV sPLA2 resulted in increased Ang II–induced cardiac fibrosis that was most pronounced in perivascular regions. Perivascular collagen, visualized by picrosirius red staining, was associated with increased TUNEL staining and increased immunopositivity for macrophages and myofibroblasts and nicotinamide adenine dinucleotide phosphate oxidase (NOX)-2 and NOX-4, respectively. Our findings indicate that GV sPLA2 modulates pathological responses to Ang II, with different outcomes for AAA and cardiac fibrosis. PMID:22813854

  14. Protection against lethal vaccinia virus challenge in HLA-A2 transgenic mice by immunization with a single CD8+ T-cell peptide epitope of vaccinia and variola viruses.

    PubMed

    Snyder, James T; Belyakov, Igor M; Dzutsev, Amiran; Lemonnier, François; Berzofsky, Jay A

    2004-07-01

    CD8(+) T lymphocytes have been shown to be involved in controlling poxvirus infection, but no protective cytotoxic T-lymphocyte (CTL) epitopes are defined for variola virus, the causative agent of smallpox, or for vaccinia virus. Of several peptides in vaccinia virus predicted to bind HLA-A2.1, three, VETFsm(498-506), A26L(6-14), and HRP2(74-82), were found to bind HLA-A2.1. Splenocytes from HLA-A2.1 transgenic mice immunized with vaccinia virus responded only to HRP2(74-82) at 1 week and to all three epitopes by ex vivo enzyme-linked immunosorbent spot (ELISPOT) assay at 4 weeks postimmunization. To determine if these epitopes could elicit a protective CD8(+) T-cell response, we challenged peptide-immunized HLA-A2.1 transgenic mice intranasally with a lethal dose of the WR strain of vaccinia virus. HRP2(74-82) peptide-immunized mice recovered from infection, while naïve mice died. Depletion of CD8(+) T cells eliminated protection. Protection of HHD-2 mice, lacking mouse class I major histocompatibility complex molecules, implicates CTLs restricted by human HLA-A2.1 as mediators of protection. These results suggest that HRP2(74-82), which is shared between vaccinia and variola viruses, may be a CD8(+) T-cell epitope of vaccinia virus that will provide cross-protection against smallpox in HLA-A2.1-positive individuals, representing almost half the population.

  15. Protection against Lethal Vaccinia Virus Challenge in HLA-A2 Transgenic Mice by Immunization with a Single CD8+ T-Cell Peptide Epitope of Vaccinia and Variola Viruses

    PubMed Central

    Snyder, James T.; Belyakov, Igor M.; Dzutsev, Amiran; Lemonnier, François; Berzofsky, Jay A.

    2004-01-01

    CD8+ T lymphocytes have been shown to be involved in controlling poxvirus infection, but no protective cytotoxic T-lymphocyte (CTL) epitopes are defined for variola virus, the causative agent of smallpox, or for vaccinia virus. Of several peptides in vaccinia virus predicted to bind HLA-A2.1, three, VETFsm(498-506), A26L(6-14), and HRP2(74-82), were found to bind HLA-A2.1. Splenocytes from HLA-A2.1 transgenic mice immunized with vaccinia virus responded only to HRP2(74-82) at 1 week and to all three epitopes by ex vivo enzyme-linked immunosorbent spot (ELISPOT) assay at 4 weeks postimmunization. To determine if these epitopes could elicit a protective CD8+ T-cell response, we challenged peptide-immunized HLA-A2.1 transgenic mice intranasally with a lethal dose of the WR strain of vaccinia virus. HRP2(74-82) peptide-immunized mice recovered from infection, while naïve mice died. Depletion of CD8+ T cells eliminated protection. Protection of HHD-2 mice, lacking mouse class I major histocompatibility complex molecules, implicates CTLs restricted by human HLA-A2.1 as mediators of protection. These results suggest that HRP2(74-82), which is shared between vaccinia and variola viruses, may be a CD8+ T-cell epitope of vaccinia virus that will provide cross-protection against smallpox in HLA-A2.1-positive individuals, representing almost half the population. PMID:15194781

  16. COMPARISON OF OVERALL METABOLISM OF 2, 3, 7, 8-TETRACHLORODIBENZO-P-DIOXIN IN CYP1A2(-/-) KNOCKOUT AND C57BL/6N PARENTAL STRAINS OF MICE

    EPA Science Inventory

    Comparison of Overall Metabolism of 2,3,7,8-TCDD
    in CYP1A2 (-/-) Knockout and C57BL/6N Parental Strains of Mice

    Heldur Hakk* and Janet J. Diliberto**

    * USDA-ARS Biosciences Research Laboratory, P.O. Box 5674, Fargo, ND, USA
    ** US-EPA ORD, National Health Eff...

  17. Mineralocorticoid Receptor Deficiency in T Cells Attenuates Pressure Overload-Induced Cardiac Hypertrophy and Dysfunction Through Modulating T-Cell Activation.

    PubMed

    Li, Chao; Sun, Xue-Nan; Zeng, Meng-Ru; Zheng, Xiao-Jun; Zhang, Yu-Yao; Wan, Qiangyou; Zhang, Wu-Chang; Shi, Chaoji; Du, Lin-Juan; Ai, Tang-Jun; Liu, Yuan; Liu, Yan; Du, Li-Li; Yi, Yi; Yu, Ying; Duan, Sheng-Zhong

    2017-07-01

    Although antagonists of mineralocorticoid receptor (MR) have been widely used to treat heart failure, the underlying mechanisms are incompletely understood. Recent reports show that T cells play important roles in pathologic cardiac hypertrophy and heart failure. However, it is unclear whether and how MR functions in T cells under these pathologic conditions. We found that MR antagonist suppressed abdominal aortic constriction-induced cardiac hypertrophy and decreased the accumulation and activation of CD4 + and CD8 + T cells in mouse heart. T-cell MR knockout mice manifested suppressed cardiac hypertrophy, fibrosis, and dysfunction compared with littermate control mice after abdominal aortic constriction. T-cell MR knockout mice had less cardiac inflammatory response, which was illustrated by decreased accumulation of myeloid cells and reduced expression of inflammatory cytokines. Less amounts and activation of T cells were observed in the heart of T-cell MR knockout mice after abdominal aortic constriction. In vitro studies showed that both MR antagonism and deficiency repressed activation of T cells, whereas MR overexpression elevated activation of T cells. These results demonstrated that MR blockade in T cells protected against abdominal aortic constriction-induced cardiac hypertrophy and dysfunction. Mechanistically, MR directly regulated T-cell activation and modulated cardiac inflammation. Targeting MR in T cells specifically may be a feasible strategy for more effective treatment of pathologic cardiac hypertrophy and heart failure. © 2017 American Heart Association, Inc.

  18. Carcinogenicity of acrylamide in B6C3F(1) mice and F344/N rats from a 2-year drinking water exposure.

    PubMed

    Beland, Frederick A; Mellick, Paul W; Olson, Greg R; Mendoza, Maria C B; Marques, M Matilde; Doerge, Daniel R

    2013-01-01

    Acrylamide is a component of roasted coffee and certain baked and fried carbohydrate-rich foods prepared at high temperatures. We have assessed the carcinogenicity of acrylamide in male and female B6C3F(1) mice and F344/N rats administered 0, 0.0875, 0.175, 0.35, or 0.70mM acrylamide in the drinking water ad libitum for 2 years. Acrylamide caused significant dose-related decreasing trends in the body weights of F344/N rats. Acrylamide administration resulted in significant dose-related decreasing trends in survival in both sexes of B6C3F(1) mice and in female F344/N rats. Histopathological analyses indicated significant dose-related increases in Harderian gland and lung tumors in male and female B6C3F(1) mice. Male B6C3F(1) mice also had a significantly increased incidence of forestomach tumors, while female B6C3F(1) mice had significant dose-related increases in mammary gland, ovary, and skin tumors. In male and female F344/N rats, there were significant increases in thyroid tumors. Male F344/N rats also had significant dose-related increases in testes, heart, and pancreas tumors, while female F344 rats demonstrated significant increases in clitoral gland, mammary gland, oral cavity, and skin tumors. These results, combined with previous mechanistic studies, provide strong support for the concept that acrylamide is activated to a carcinogen through metabolism to glycidamide. Published by Elsevier Ltd.

  19. Heterologous human/rat HER2-specific exosome-targeted T cell vaccine stimulates potent humoral and CTL responses leading to enhanced circumvention of HER2 tolerance in double transgenic HLA-A2/HER2 mice.

    PubMed

    Xie, Yufeng; Wu, Jie; Xu, Aizhang; Ahmeqd, Shahid; Sami, Amer; Chibbar, Rajni; Freywald, Andrew; Zheng, Changyu; Xiang, Jim

    2018-03-07

    DNA vaccines composed of heterologous human HER2 and rat neu sequences induce stronger antibody response and protective antitumor immunity than either HER2 or neu DNA vaccines in transgenic mice. We previously developed HER2-specific exosome-targeted T-cell vaccine HER2-T EXO capable of stimulating HER2-specific CD8 + T-cell responses, but only leading to partial protective immunity in double-transgenic HLA-A2/HER2 mice with self-immune tolerance to HER2. Here, we constructed an adenoviral vector AdV HuRt expressing HuRt fusion protein composed of NH 2 -HER2 1-407 (Hu) and COOH-neu 408-690 (Rt) fragments, and developed a heterologous human/rat HER2-specific exosome-targeted T-cell vaccine HuRt-T EXO using polyclonal CD4 + T-cells uptaking exosomes released by AdV HuRt -transfected dendritic cells. We found that the HuRt-T EXO vaccine stimulates enhanced CD4 + T-cell responses leading to increased induction of HER2-specific antibody (∼70 µg/ml) compared to that (∼40 µg/ml) triggered by the homologous HER2-T EXO vaccine. By using PE-H-2K d /HER2 23-71 tetramer, we determined that HuRt-T EXO stimulates stronger HER2-specific CD8 + T-cell responses eradicating 90% of HER2-specific target cells, while HER2-T EXO -induced CD8 + T-cell responses only eliminating 53% targets. Furthermore, HuRt-T EXO , but not HER2-T EXO vaccination, is capable of suppressing early stage-established HER2-expressing 4T1 HER2 breast cancer in its lung metastasis or subcutaneous form in BALB/c mice, and of completely protecting transgenic HLA-A2/HER2 mice from growth of HLA-A2/HER2-expressing BL6-10 A2/HER2 melanoma. HuRt-T EXO -stimulated HER2-specific CD8 + T-cells not only are cytolytic to trastuzumab-resistant HLA-A2/HER2-expressing BT474/A2 breast tumor cells in vitro but also eradicates pre-established BT474/A2 tumors in athymic nude mice. Therefore, our novel heterologous human/rat HER2-specific T-cell vaccine HuRt-T EXO, circumventing HER2 tolerance, may provide a new

  20. Online LI-rTMS during a Visual Learning Task: Differential Impacts on Visual Circuit and Behavioral Plasticity in Adult Ephrin-A2A5–/– Mice

    PubMed Central

    Poh, Eugenia Z.; Harvey, Alan R.; Makowiecki, Kalina

    2018-01-01

    Abstract Repetitive transcranial magnetic stimulation (rTMS) induces plasticity in normal and abnormal neural circuitries, an effect that may be influenced by intrinsic brain activity during treatment. Here, we study potential synergistic effects between low-intensity rTMS (LI-rTMS) and concurrent neural activity in promoting circuit reorganization and enhancing visual behavior. We used ephrin-A2A5–/– mice, which are known to possess visuotopic mapping errors that are ameliorated by LI-rTMS, and assessed the impact of stimulation when mice were engaged in a visual learning task. A detachable coil was affixed to each mouse, and animals underwent 2 wk of 10-min daily training in a two-choice visual discrimination task with concurrent LI-rTMS or sham stimulation. No-task controls (+LI-rTMS/sham) were placed in the task arena without visual task training. At the end of the experiment, visuomotor tracking behavior was assessed, and corticotectal and geniculocortical pathway organization was mapped by injections of fluorescent tracers into the primary visual cortex. Consistent with previous results, LI-rTMS alone improved geniculocortical and corticotectal topography, but combining LI-rTMS with the visual learning task prevented beneficial corticotectal reorganization and had no additional effect on geniculocortical topography or visuomotor tracking performance. Unexpectedly, there was a significant increase in the total number of trials completed by task + LI-rTMS mice in the visual learning task. Comparison with wild-type mice revealed that ephrin-A2A5–/– mice had reduced accuracy and response rates, suggesting a goal-directed behavioral deficit, which was improved by LI-rTMS. Our results suggest that concurrent brain activity during behavior interacts with LI-rTMS, altering behavior and different visual circuits in an abnormal system. PMID:29464193

  1. Quantitative trait locus mapping in mice identifies phospholipase Pla2g12a as novel atherosclerosis modifier.

    PubMed

    Nicolaou, Alexandros; Northoff, Bernd H; Sass, Kristina; Ernst, Jana; Kohlmaier, Alexander; Krohn, Knut; Wolfrum, Christian; Teupser, Daniel; Holdt, Lesca M

    2017-10-01

    In a previous work, a female-specific atherosclerosis risk locus on chromosome (Chr) 3 was identified in an intercross of atherosclerosis-resistant FVB and atherosclerosis-susceptible C57BL/6 (B6) mice on the LDL-receptor deficient (Ldlr -/- ) background. It was the aim of the current study to identify causative genes at this locus. We established a congenic mouse model, where FVB.Chr3 B6/B6 mice carried an 80 Mb interval of distal Chr3 on an otherwise FVB.Ldlr -/- background, to validate the Chr3 locus. Candidate genes were identified using genome-wide expression analyses. Differentially expressed genes were validated using quantitative PCRs in F0 and F2 mice and their functions were investigated in pathophysiologically relevant cells. Fine-mapping of the Chr3 locus revealed two overlapping, yet independent subloci for female atherosclerosis susceptibility: when transmitted by grandfathers to granddaughters, the B6 risk allele increased atherosclerosis and downregulated the expression of the secreted phospholipase Pla2g12a (2.6 and 2.2 fold, respectively); when inherited by grandmothers, the B6 risk allele induced vascular cell adhesion molecule 1 (Vcam1). Down-regulation of Pla2g12a and up-regulation of Vcam1 were validated in female FVB.Chr3 B6/B6 congenic mice, which developed 2.5 greater atherosclerotic lesions compared to littermate controls (p=0.039). Pla2g12a was highly expressed in aortic endothelial cells in vivo, and knocking-down Pla2g12a expression by RNAi in cultured vascular endothelial cells or macrophages increased their adhesion to ECs in vitro. Our data establish Pla2g12a as an atheroprotective candidate gene in mice, where high expression levels in ECs and macrophages may limit the recruitment and accumulation of these cells in nascent atherosclerotic lesions. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Enhancement of D1 dopamine receptor-mediated locomotor stimulation in M4 muscarinic acetylcholine receptor knockout mice

    PubMed Central

    Gomeza, Jesus; Zhang, Lu; Kostenis, Evi; Felder, Christian; Bymaster, Frank; Brodkin, Jesse; Shannon, Harlan; Xia, Bing; Deng, Chu-xia; Wess, Jürgen

    1999-01-01

    Muscarinic acetylcholine receptors (M1–M5) regulate many key functions of the central and peripheral nervous system. Primarily because of the lack of receptor subtype-selective ligands, the precise physiological roles of the individual muscarinic receptor subtypes remain to be elucidated. Interestingly, the M4 receptor subtype is expressed abundantly in the striatum and various other forebrain regions. To study its potential role in the regulation of locomotor activity and other central functions, we used gene-targeting technology to create mice that lack functional M4 receptors. Pharmacologic analysis of M4 receptor-deficient mice indicated that M4 receptors are not required for muscarinic receptor-mediated analgesia, tremor, hypothermia, and salivation. Strikingly, M4 receptor-deficient mice showed an increase in basal locomotor activity and greatly enhanced locomotor responses (as compared with their wild-type littermates) after activation of D1 dopamine receptors. These results indicate that M4 receptors exert inhibitory control on D1 receptor-mediated locomotor stimulation, probably at the level of striatal projection neurons where the two receptors are coexpressed at high levels. Our findings offer new perspectives for the treatment of Parkinson’s disease and other movement disorders that are characterized by an imbalance between muscarinic cholinergic and dopaminergic neurotransmission. PMID:10468635

  3. Immunogenicity Evaluation of a Rationally Designed Polytope Construct Encoding HLA-A*0201 Restricted Epitopes Derived from Leishmania major Related Proteins in HLA-A2/DR1 Transgenic Mice: Steps toward Polytope Vaccine

    PubMed Central

    Seyed, Negar; Taheri, Tahereh; Vauchy, Charline; Dosset, Magalie; Godet, Yann; Eslamifar, Ali; Sharifi, Iraj; Adotevi, Olivier; Borg, Christophe; Rohrlich, Pierre Simon; Rafati, Sima

    2014-01-01

    Background There are several reports demonstrating the role of CD8 T cells against Leishmania species. Therefore peptide vaccine might represent an effective approach to control the infection. We developed a rational polytope-DNA construct encoding immunogenic HLA-A2 restricted peptides and validated the processing and presentation of encoded epitopes in a preclinical mouse model humanized for the MHC-class-I and II. Methods and Findings HLA-A*0201 restricted epitopes from LPG-3, LmSTI-1, CPB and CPC along with H-2Kd restricted peptides, were lined-up together as a polytope string in a DNA construct. Polytope string was rationally designed by harnessing advantages of ubiquitin, spacers and HLA-DR restricted Th1 epitope. Endotoxin free pcDNA plasmid expressing the polytope was inoculated into humanized HLA-DRB1*0101/HLA-A*0201 transgenic mice intramuscularly 4 days after Cardiotoxin priming followed by 2 boosters at one week interval. Mice were sacrificed 10 days after the last booster, and splenocytes were subjected to ex-vivo and in-vitro evaluation of specific IFN-γ production and in-vitro cytotoxicity against individual peptides by ELISpot and standard chromium-51(51Cr) release assay respectively. 4 H-2Kd and 5 HLA-A*0201 restricted peptides were able to induce specific CD8 T cell responses in BALB/C and HLA-A2/DR1 mice respectively. IFN-γ and cytolytic activity together discriminated LPG-3-P1 as dominant, LmSTI-1-P3 and LmSTI-1-P6 as subdominant with both cytolytic activity and IFN-γ production, LmSTI-1-P4 and LPG-3-P5 as subdominant with only IFN-γ production potential. Conclusions Here we described a new DNA-polytope construct for Leishmania vaccination encompassing immunogenic HLA-A2 restricted peptides. Immunogenicity evaluation in HLA-transgenic model confirmed CD8 T cell induction with expected affinities and avidities showing almost efficient processing and presentation of the peptides in relevant preclinical model. Further evaluation will determine

  4. In vivo immunogenicity of Tax(11-19) epitope in HLA-A2/DTR transgenic mice: implication for dendritic cell-based anti-HTLV-1 vaccine.

    PubMed

    Sagar, Divya; Masih, Shet; Schell, Todd; Jacobson, Steven; Comber, Joseph D; Philip, Ramila; Wigdahl, Brian; Jain, Pooja; Khan, Zafar K

    2014-05-30

    Viral oncoprotein Tax plays key roles in transformation of human T-cell leukemia virus (HTLV-1)-infected T cells leading to adult T-cell leukemia (ATL), and is the key antigen recognized during HTLV-associated myelopathy (HAM). In HLA-A2+ asymptomatic carriers as well as ATL and HAM patients, Tax(11-19) epitope exhibits immunodominance. Here, we evaluate CD8 T-cell immune response against this epitope in the presence and absence of dendritic cells (DCs) given the recent encouraging observations made with Phase 1 DC-based vaccine trial for ATL. To facilitate these studies, we first generated an HLA-A2/DTR hybrid mouse strain carrying the HLA-A2.1 and CD11c-DTR genes. We then studied CD8 T-cell immune response against Tax(11-19) epitope delivered in the absence or presence of Freund's adjuvant and/or DCs. Overall results demonstrate that naturally presented Tax epitope could initiate an antigen-specific CD8T cell response in vivo but failed to do so upon DC depletion. Presence of adjuvant potentiated Tax(11-19)-specific response. Elevated serum IL-6 levels coincided with depletion of DCs whereas decreased TGF-β was associated with adjuvant use. Thus, Tax(11-19) epitope is a potential candidate for the DC-based anti-HTLV-1 vaccine and the newly hybrid mouse strain could be used for investigating DC involvement in human class-I-restricted immune responses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Transplanted hypothalamic neurons restore leptin signaling and ameliorate obesity in db/db mice.

    PubMed

    Czupryn, Artur; Zhou, Yu-Dong; Chen, Xi; McNay, David; Anderson, Matthew P; Flier, Jeffrey S; Macklis, Jeffrey D

    2011-11-25

    Evolutionarily old and conserved homeostatic systems in the brain, including the hypothalamus, are organized into nuclear structures of heterogeneous and diverse neuron populations. To investigate whether such circuits can be functionally reconstituted by synaptic integration of similarly diverse populations of neurons, we generated physically chimeric hypothalami by microtransplanting small numbers of embryonic enhanced green fluorescent protein-expressing, leptin-responsive hypothalamic cells into hypothalami of postnatal leptin receptor-deficient (db/db) mice that develop morbid obesity. Donor neurons differentiated and integrated as four distinct hypothalamic neuron subtypes, formed functional excitatory and inhibitory synapses, partially restored leptin responsiveness, and ameliorated hyperglycemia and obesity in db/db mice. These experiments serve as a proof of concept that transplanted neurons can functionally reconstitute complex neuronal circuitry in the mammalian brain.

  6. Prophylactic effects of the histamine H1 receptor antagonist epinastine and the dual thromboxane A2 receptor and chemoattractant receptor-homologous molecule expressed on Th2 cells antagonist ramatroban on allergic rhinitis model in mice.

    PubMed

    Suzuki, Yuh; Inoue, Toshio; Yamamoto, Atsuki; Sugimoto, Yukio

    2011-01-01

    The prophylactic use of anti-allergic drugs has been proposed to be effective in the treatment of seasonal allergic rhinitis in humans. However, there is little information regarding the prophylactic effect of thromboxane A(2) (TXA(2)) receptor antagonist on allergic rhinitis. Recent studies revealed that a TXA(2) receptor antagonist ramatroban could block the prostaglandin D(2) (PGD(2)) receptor and chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2). In the present study, we investigated the prophylactic effects of the histamine H(1) receptor antagonist epinastine and the TXA(2) receptor antagonist ramatroban and seratrodast on mouse models of allergic rhinitis. Female BALB/c mice were sensitized by an intraperitoneal injection of ovalbumin and alum on days 0, 5, 14 and 21. Seven days later, mice were sensitized by intranasal application of ovalbumin thrice a week. Drugs were administered once a day from day 22. The severity of allergic rhinitis was assessed by determining the extent of 2 nasal allergic symptoms (sneezing and nasal rubbing). Histamine sensitivity and eosinophil infiltration into the nasal mucosa were also determined. Epinastine and ramatroban significantly reduced nasal symptoms and the number of eosinophils in the nasal mucosa. Seratrodast showed no effect on nasal symptoms and eosinophil infiltration into the nasal mucosa. In addition, histamine sensitivity was reduced by epinastine and ramatroban. These results indicate that epinastine and ramatroban induce the prophylactic effect on allergic rhinitis.

  7. Energy homeostasis in leptin deficient Lepob/ob mice

    PubMed Central

    Skowronski, Alicja A.; Ravussin, Yann; Leibel, Rudolph L.

    2017-01-01

    Maintenance of reduced body weight is associated both with reduced energy expenditure per unit metabolic mass and increased hunger in mice and humans. Lowered circulating leptin concentration, due to decreased fat mass, provides a primary signal for this response. However, leptin deficient (Lepob/ob) mice (and leptin receptor deficient Zucker rats) reduce energy expenditure following weight reduction by a necessarily non-leptin dependent mechanisms. To identify these mechanisms, Lepob/ob mice were fed ad libitum (AL group; n = 21) or restricted to 3 kilocalories of chow per day (CR group, n = 21). After losing 20% of initial weight (in approximately 2 weeks), the CR mice were stabilized at 80% of initial body weight for two weeks by titrated refeeding, and then released from food restriction. CR mice conserved energy (-17% below predicted based on body mass and composition during the day; -52% at night); and, when released to ad libitum feeding, CR mice regained fat and lean mass (to AL levels) within 5 weeks. CR mice did so while their ad libitum caloric intake was equal to that of the AL animals. While calorically restricted, the CR mice had a significantly lower respiratory exchange ratio (RER = 0.89) compared to AL (0.94); after release to ad libitum feeding, RER was significantly higher (1.03) than in the AL group (0.93), consistent with their anabolic state. These results confirm that, in congenitally leptin deficient animals, leptin is not required for compensatory reduction in energy expenditure accompanying weight loss, but suggest that the hyperphagia of the weight-reduced state is leptin-dependent. PMID:29261744

  8. Immunizing Adult Female Mice with a TcpA-A2-CTB Chimera Provides a High Level of Protection for Their Pups in the Infant Mouse Model of Cholera

    PubMed Central

    Price, Gregory A.; Holmes, Randall K.

    2014-01-01

    Vibrio cholerae expresses two primary virulence factors, cholera toxin (CT) and the toxin-coregulated pilus (TCP). CT causes profuse watery diarrhea, and TCP (composed of repeating copies of the major pilin TcpA) is required for intestinal colonization by V. cholerae. Antibodies to CT or TcpA can protect against cholera in animal models. We developed a TcpA holotoxin-like chimera (TcpA-A2-CTB) to elicit both anti-TcpA and anti-CTB antibodies and evaluated its immunogenicity and protective efficacy in the infant mouse model of cholera. Adult female CD-1 mice were immunized intraperitoneally three times with the TcpA-A2-CTB chimera and compared with similar groups immunized with a TcpA+CTB mixture, TcpA alone, TcpA with Salmonella typhimurium flagellin subunit FliC as adjuvant, or CTB alone. Blood and fecal samples were analyzed for antigen-specific IgG or IgA, respectively, using quantitative ELISA. Immunized females were mated; their reared offspring were challenged orogastrically with 10 or 20 LD50 of V. cholerae El Tor N16961; and vaccine efficacy was assessed by survival of the challenged pups at 48 hrs. All pups from dams immunized with the TcpA-A2-CTB chimera or the TcpA+CTB mixture survived at both challenge doses. In contrast, no pups from dams immunized with TcpA+FliC or CTB alone survived at the 20 LD50 challenge dose, although the anti-TcpA or anti-CTB antibody level elicited by these immunizations was comparable to the corresponding antibody level achieved by immunization with TcpA-A2-CTB or TcpA+CTB. Taken together, these findings comprise strong preliminary evidence for synergistic action between anti-TcpA and anti-CTB antibodies in protecting mice against cholera. Weight loss analysis showed that only immunization of dams with TcpA-A2-CTB chimera or TcpA+CTB mixture protected their pups against excess weight loss from severe diarrhea. These data support the concept of including both TcpA and CTB as immunogens in development of an effective multivalent

  9. Genetics Home Reference: leptin receptor deficiency

    MedlinePlus

    ... YS. The role of leptin-melanocortin system and human weight regulation: lessons from experiments of nature. Ann Acad Med Singapore. 2009 Jan;38(1):34-11. Review. Citation on PubMed Mazen I, El-Gammal M, Abdel-Hamid M, Farooqi IS, ... Human Services National Institutes of Health National Library of ...

  10. Glucagon receptor knockout mice are protected against acute olanzapine-induced hyperglycemia.

    PubMed

    Castellani, Laura N; Peppler, Willem T; Sutton, Charles D; Whitfield, Jamie; Charron, Maureen J; Wright, David C

    2017-08-01

    To determine if glucagon is involved in mediating the increase in blood glucose levels caused by the second-generation antipsychotic drug olanzapine. Whole body glucagon receptor deficient mice (Gcgr -/- ) or WT littermate controls were injected with olanzapine (5mg/kg BW IP) and changes in blood glucose measured over the following 120min. Separate cohorts of mice were treated with olanzapine and changes in pyruvate tolerance, insulin tolerance and whole body substrate oxidation were determined. Olanzapine treatment increased serum glucagon and lead to rapid increases in blood glucose concentrations in WT mice. Gcgr -/- mice were protected against olanzapine-induced increases in blood glucose but this was not explained by differences in terminal serum insulin concentrations, enhanced AKT phosphorylation in skeletal muscle, adipose tissue or liver or differences in RER. In both genotypes olanzapine induced an equivalent degree of insulin resistance as measured using an insulin tolerance test. Olanzapine treatment led to an exaggerated glucose response to a pyruvate challenge in WT but not Gcgr -/- mice and this was paralleled by reductions in the protein content of PEPCK and G6Pase in livers from Gcgr -/- mice. Gcgr -/- mice are protected against olanzapine-induced increases in blood glucose. This is likely a result of reductions in liver glucose output, perhaps secondary to decreases in PEPCK and G6Pase protein content. Our findings highlight the central role of the liver in mediating olanzapine-induced disturbances in glucose homeostasis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Modulation of sweet taste sensitivities by endogenous leptin and endocannabinoids in mice

    PubMed Central

    Niki, Mayu; Jyotaki, Masafumi; Yoshida, Ryusuke; Yasumatsu, Keiko; Shigemura, Noriatsu; DiPatrizio, Nicholas V; Piomelli, Daniele; Ninomiya, Yuzo

    2015-01-01

    Leptin is an anorexigenic mediator that reduces food intake by acting on hypothalamic receptor Ob-Rb. In contrast, endocannabinoids are orexigenic mediators that act via cannabinoid CB1 receptors in hypothalamus, limbic forebrain, and brainstem. In the peripheral taste system, leptin administration selectively inhibits behavioural, taste nerve and taste cell responses to sweet compounds. Opposing the action of leptin, endocannabinoids enhance sweet taste responses. However, potential roles of endogenous leptin and endocannabinoids in sweet taste remain unclear. Here, we used pharmacological antagonists (Ob-Rb: L39A/D40A/F41A (LA), CB1: AM251) and examined the effects of their blocking activation of endogenous leptin and endocannabinoid signalling on taste responses in lean control, leptin receptor deficient db/db, and diet-induced obese (DIO) mice. Lean mice exhibited significant increases in chorda tympani (CT) nerve responses to sweet compounds after LA administration, while they showed no significant changes in CT responses after AM251. In contrast, db/db mice showed clear suppression of CT responses to sweet compounds after AM251, increased endocannabinoid (2-arachidonoyl-sn-glycerol (2-AG)) levels in the taste organ, and enhanced expression of a biosynthesizing enzyme (diacylglycerol lipase α (DAGLα)) of 2-AG in taste cells. In DIO mice, the LA effect was gradually decreased and the AM251 effect was increased during the course of obesity. Taken together, our results suggest that circulating leptin, but not local endocannabinoids, may be a dominant modulator for sweet taste in lean mice; however, endocannabinoids may become more effective modulators of sweet taste under conditions of deficient leptin signalling, possibly due to increased production of endocannabinoids in taste tissue. Key points Potential roles of endogenous leptin and endocannabinoids in sweet taste were examined by using pharmacological antagonists and mouse models including leptin receptor

  12. Dietary fish oil exerts hypolipidemic effects in lean and insulin sensitizing effects in obese LDLR-/- mice.

    PubMed

    Saraswathi, Viswanathan; Morrow, Jason D; Hasty, Alyssa H

    2009-12-01

    Obesity is often associated with dyslipidemia, insulin resistance, and hypertension. Together, these metabolic perturbations greatly increase the risk of developing cardiovascular disease and diabetes. Although fish oil is a well-established hypolipidemic agent, the mechanisms by which it mediates its lipid-lowering effects are not clear. In addition, it has not been established whether dietary fish oil has different effects in lean and obese mice. LDL receptor deficient (LDLR-/-) and leptin deficient mice on a LDLR-/- background (ob/ob;LDLR-/-) were fed a high fat diet (39% total fat) supplemented with 6% olive oil or fish oil for 6 wk. Fish oil supplementation resulted in lower concentrations of plasma total cholesterol (P < 0.01), triglycerides (P < 0.01), and free fatty acids (P < 0.001) in lean LDLR-/- mice, but not in ob/ob;LDLR-/- mice. In contrast, a fish oil diet did not modulate insulin sensitivity in lean LDLR-/- mice, but it improved insulin sensitivity in ob/ob;LDLR-/- mice (P < 0.05) compared with olive oil fed ob/ob;LDLR-/- mice. Interestingly, plasma adiponectin concentrations were significantly higher and hepatic steatosis was reduced in both mouse models upon fish oil feeding. Finally, fish oil fed LDLR-/- mice exhibited higher hepatic AMP activated protein kinase (AMPK) phosphorylation (P < 0.05), whereas AMPK phosphorylation was not elevated by fish oil feeding in ob/ob;LDLR-/- mice. Taken together, our data suggest that fish oil reduces hepatic steatosis in both lean and obese mice, has potent plasma lipid lowering effects in lean mice, and exerts insulin sensitizing effects in obese mice.

  13. Leptin Increases Striatal Dopamine D2 Receptor Binding in Leptin-Deficient Obese (ob/ob) Mice

    SciTech Connect

    Pfaffly, J.; Michaelides, M.; Wang, G-J.

    2010-06-01

    Peripheral and central leptin administration have been shown to mediate central dopamine (DA) signaling. Leptin-receptor deficient rodents show decreased DA D2 receptor (D2R) binding in striatum and unique DA profiles compared to controls. Leptin-deficient mice show increased DA activity in reward-related brain regions. The objective of this study was to examine whether basal D2R-binding differences contribute to the phenotypic behaviors of leptin-deficient ob/ob mice, and whether D2R binding is altered in response to peripheral leptin treatment in these mice. Leptin decreased body weight, food intake, and plasma insulin concentration in ob/ob mice but not in wild-type mice. Basal striatal D2Rmore » binding (measured with autoradiography [{sup 3}H] spiperone) did not differ between ob/ob and wild-type mice but the response to leptin did. In wild-type mice, leptin decreased striatal D2R binding, whereas, in ob/ob mice, leptin increased D2R binding. Our findings provide further evidence that leptin modulates D2R expression in striatum and that these effects are genotype/phenotype dependent.« less

  14. Subcutaneous Angiotensin II Infusion using Osmotic Pumps Induces Aortic Aneurysms in Mice.

    PubMed

    Lu, Hong; Howatt, Deborah A; Balakrishnan, Anju; Moorleghen, Jessica J; Rateri, Debra L; Cassis, Lisa A; Daugherty, Alan

    2015-09-28

    Osmotic pumps continuously deliver compounds at a constant rate into small animals. This article introduces a standard protocol used to induce aortic aneurysms via subcutaneous infusion of angiotensin II (AngII) from implanted osmotic pumps. This protocol includes calculation of AngII amount and dissolution, osmotic pump filling, implantation of osmotic pumps subcutaneously, observation after pump implantation, and harvest of aortas to visualize aortic aneurysms in mice. Subcutaneous infusion of AngII through osmotic pumps following this protocol is a reliable and reproducible technique to induce both abdominal and thoracic aortic aneurysms in mice. Infusion durations range from a few days to several months based on the purpose of the study. AngII 1,000 ng/kg/min is sufficient to provide maximal effects on abdominal aortic aneurysmal formation in male hypercholesterolemic mouse models such as apolipoprotein E deficient or low-density lipoprotein receptor deficient mice. Incidence of abdominal aortic aneurysms induced by AngII infusion via osmotic pumps is 5-10 times lower in female hypercholesterolemic mice and also lower in both genders of normocholesterolemic mice. In contrast, AngII-induced thoracic aortic aneurysms in mice are not hypercholesterolemia or gender-dependent. Importantly, multiple features of this mouse model recapitulate those of human aortic aneurysms.

  15. Sigma-1 (σ₁) receptor deficiency reduces β-amyloid(25-35)-induced hippocampal neuronal cell death and cognitive deficits through suppressing phosphorylation of the NMDA receptor NR2B.

    PubMed

    Yin, Jun; Sha, Sha; Chen, Tingting; Wang, Conghui; Hong, Juan; Jie, Pinghui; Zhou, Rong; Li, Lin; Sokabe, Masahiro; Chen, Ling

    2015-02-01

    In early Alzheimer's disease (AD) brain, reduction of sigma-1 receptors (σ1R) is detected. In this study, we employed male heterozygous σ1R knockout (σ1R(+/-)) mice showing normal cognitive performance to investigate association of σ1R deficiency with AD risk. Herein we report that a single injection (i.c.v.) of Aβ(25-35) impaired spatial memory with approximately 25% death of pyramidal cells in the hippocampal CA1 region of WT mice (Aβ(25-35)-WT mice), whereas it did not cause such impairments in σ1R(+/-) mice (Aβ(25-35)-σ1R(+/-) mice). Compared with WT mice, Aβ(25-35)-WT mice showed increased levels of NMDA-activated currents (INMDA) and NR2B phosphorylation (phospho-NR2B) in the hippocampal CA1 region at 48 h after Aβ25-35-injection (post-Aβ(25-35)) followed by approximately 40% decline at 72 h post-Aβ(25-35) of their respective control levels, which was inhibited by the σ1R antagonist NE100. In Aβ(25-35)-WT mice, the administration of NR2B inhibitor Ro25-6981 or NE100 on day 1-4 post-Aβ(25-35) attenuated the memory deficits and loss of pyramidal cells. By contrast, Aβ(25-35)-σ1R(+/-) mice showed a slight increase in the INMDA density and the phospho-NR2B at 48 h or 72 h post-Aβ25-35 compared to σ1R(+/-) mice. Treatment with σ1R agonist PRE084 in Aβ(25-35)-σ1R(+/-) mice caused the same changes in the INMDA density and the phospho-NR2B as those in Aβ(25-35)-WT mice. Furthermore, Aβ(25-35)-σ1R(+/-) mice treated with the NMDA receptor agonist NMDA or PRE084 on day 1-4 post-Aβ(25-35) showed a loss of neuronal cells and memory impairment. These results indicate that the σ1R deficiency can reduce Aβ(25-35)-induced neuronal cell death and cognitive deficits through suppressing Aβ(25-35)-enhanced NR2B phosphorylation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Rubimetide, humanin, and MMK1 exert anxiolytic-like activities via the formyl peptide receptor 2 in mice followed by the successive activation of DP1, A2A, and GABAA receptors.

    PubMed

    Zhao, Hui; Sonada, Soushi; Yoshikawa, Akihiro; Ohinata, Kousaku; Yoshikawa, Masaaki

    2016-09-01

    Rubimetide (Met-Arg-Trp), which had been isolated as an antihypertensive peptide from an enzymatic digest of spinach ribulose-bisphosphate carboxylase/oxygenase (Rubisco), showed anxiolytic-like activity prostaglandin (PG) D2-dependent manner in the elevated plus-maze test after administration at a dose of 0.1mg/kg (ip.) or 1mg/kg (p.o.) in male mice of ddY strain. In this study, we found that rubimetide has weak affinities for the FPR1 and FPR2, subtypes of formyl peptide receptor (FPR). The anxiolytic-like activity of rubimetide (0.1mg/kg, ip.) was blocked by WRW4, an antagonist of FPR2, but not by Boc-FLFLF, an antagonist of FPR1, suggesting that the anxiolytic-like activity was mediated by the FPR2. Humanin, an endogenous agonist peptide of the FPR2, exerted an anxiolytic-like activity after intracerebroventricular (icv) administration, which was also blocked by WRW4. MMK1, a synthetic agonist peptide of the FPR2, also exerted anxiolytic-like activity. Thus, FPR2 proved to mediate anxiolytic-like effect as the first example of central effect exerted by FPR agonists. As well as the anxiolytic-like activity of rubimetide, that of MMK1 was blocked by BW A868C, an antagonist of the DP1-receptor. Furthermore, anxiolytic-like activity of rubimetide was blocked by SCH58251 and bicuculline, antagonists for adenosine A2A and GABAA receptors, respectively. From these results, it is concluded that the anxiolytic-like activities of rubimetide and typical agonist peptides of the FPR2 were mediated successively by the PGD2-DP1 receptor, adenosine-A2A receptor, and GABA-GABAA receptor systems downstream of the FPR2. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Human metapneumovirus infection activates the TSLP pathway that drives excessive pulmonary inflammation and viral replication in mice.

    PubMed

    Lay, Margarita K; Céspedes, Pablo F; Palavecino, Christian E; León, Miguel A; Díaz, Rodrigo A; Salazar, Francisco J; Méndez, Gonzalo P; Bueno, Susan M; Kalergis, Alexis M

    2015-06-01

    Human metapneumovirus (hMPV) is a leading cause of acute respiratory tract infections in children and the elderly. The mechanism by which this virus triggers an inflammatory response still remains unknown. Here, we evaluated whether the thymic stromal lymphopoietin (TSLP) pathway contributes to lung inflammation upon hMPV infection. We found that hMPV infection promotes TSLP expression both in human airway epithelial cells and in the mouse lung. hMPV infection induced lung infiltration of OX40L(+) CD11b(+) DCs. Mice lacking the TSLP receptor deficient mice (tslpr(-/-) ) showed reduced lung inflammation and hMPV replication. These mice displayed a decreased number of neutrophils as well a reduction in levels of thymus and activation-regulated chemokine/CCL17, IL-5, IL-13, and TNF-α in the airways upon hMPV infection. Furthermore, a higher frequency of CD4(+) and CD8(+) T cells was found in tslpr(-/-) mice compared to WT mice, which could contribute to controlling viral spread. Depletion of neutrophils in WT and tslpr(-/-) mice decreased inflammation and hMPV replication. Remarkably, blockage of TSLP or OX40L with specific Abs reduced lung inflammation and viral replication following hMPV challenge in mice. Altogether, these results suggest that activation of the TSLP pathway is pivotal in the development of pulmonary pathology and pulmonary hMPV replication. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Suppressive effect of secretory phospholipase A2 inhibitory peptide on interleukin-1β-induced matrix metalloproteinase production in rheumatoid synovial fibroblasts, and its antiarthritic activity in hTNFtg mice

    PubMed Central

    2009-01-01

    Introduction Secretory phospholipase A2 (sPLA2) and matrix metalloproteinase (MMP) inhibitors are potent modulators of inflammation with therapeutic potential, but have limited efficacy in rheumatoid arthritis (RA). The objective of this study was to understand the inhibitory mechanism of phospholipase inhibitor from python (PIP)-18 peptide in cultured synovial fibroblasts (SF), and to evaluate its therapeutic potential in a human tumor necrosis factor (hTNF)-driven transgenic mouse (Tg197) model of arthritis. Methods Gene and protein expression of sPLA2-IIA, MMP-1, MMP-2, MMP-3, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-1, and TIMP-2 were analyzed by real time PCR and ELISA respectively, in interleukin (IL)-1β stimulated rheumatoid arthritis (RA) and osteoarthritis (OA) synovial fibroblasts cells treated with or without inhibitors of sPLA2 (PIP-18, LY315920) or MMPs (MMP Inhibitor II). Phosphorylation status of mitogen-activated protein kinase (MAPK) proteins was examined by cell-based ELISA. The effect of PIP-18 was compared with that of celecoxib, methotrexate, infliximab and antiflamin-2 in Tg197 mice after ip administration (thrice weekly for 5 weeks) at two doses (10, 30 mg/kg), and histologic analysis of ankle joints. Serum sPLA2 and cytokines (tumor necrosis factor (TNF)α, IL-6) were measured by Escherichia coli (E coli) assay and ELISA, respectively. Results PIP-18 inhibited sPLA2-IIA production and enzymatic activity, and suppressed production of MMPs in IL-1β-induced RA and OA SF cells. Treatment with PIP-18 blocked IL-1β-induced p38 MAPK phosphorylation and resulted in attenuation of sPLA2-IIA and MMP mRNA transcription in RA SF cells. The disease modifying effect of PIP-18 was evidenced by significant abrogation of synovitis, cartilage degradation and bone erosion in hTNF Tg197 mice. Conclusions Our results demonstrate the benefit that can be gained from using sPLA2 inhibitory peptide for RA treatment, and validate PIP-18 as a potential

  19. Dopamine D3 receptor status modulates sexual dimorphism in voluntary wheel running behavior in mice.

    PubMed

    Klinker, Florian; Ko Hnemann, Kathrin; Paulus, Walter; Liebetanz, David

    2017-08-30

    Sexual dimorphism has been described in various aspects of physiological and pathophysiological processes involving dopaminergic signaling. This might account for the different disease characteristics in men and women in e.g. Parkinson's disease or ADHD. A better understanding might contribute to the future individualization of therapy. We examined spontaneous wheel running activity of male and female mice, homo- and heterozygote for dopamine D3 receptor deficiency (D3R -/- and D3R+/-), and compared them to wild type controls. We found higher wheel running activity in female mice than in their male littermates. D3-/- mice, irrespective of sex, were also hyperactive compared to both D3+/- and wild type animals. Hyperactivity of D3-/- female mice was pronounced during the first days of wheel running but then decreased while their male counterparts continued to be hyperactive. Physical activity was menstrual cycle-dependent. Activity fluctuations were also seen in D3 receptor knockout mice and are therefore presumably independent of D3 receptor activation. Our data underscore the complex interaction of dopaminergic signaling and gonadal hormones that leads to specific running behavior. Furthermore, we detected sex- and D3 receptor status-specific reactions during novel exposure to the running wheel. These findings suggest the need for adapting dopaminergic therapies to individual factors such as sex or even menstrual cycle to optimize therapeutic success. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Maternal Antibody-Mediated Disease Enhancement in Type I Interferon-Deficient Mice Leads to Lethal Disease Associated with Liver Damage

    PubMed Central

    Lam, Jian Hang; Binte Aman, Siti Amanlina; Libau, Eshele Anak; Lee, Pei Xuan; St. John, Ashley L.; Alonso, Sylvie

    2016-01-01

    Epidemiological studies have reported that most of the severe dengue cases occur upon a secondary heterologous infection. Furthermore, babies born to dengue immune mothers are at greater risk of developing severe disease upon primary infection with a heterologous or homologous dengue virus (DENV) serotype when maternal antibodies reach sub-neutralizing concentrations. These observations have been explained by the antibody mediated disease enhancement (ADE) phenomenon whereby heterologous antibodies or sub-neutralizing homologous antibodies bind to but fail to neutralize DENV particles, allowing Fc-receptor mediated entry of the virus-antibody complexes into host cells. This eventually results in enhanced viral replication and heightened inflammatory responses. In an attempt to replicate this ADE phenomenon in a mouse model, we previously reported that upon DENV2 infection 5-week old type I and II interferon (IFN) receptors-deficient mice (AG129) born to DENV1-immune mothers displayed enhancement of disease severity characterized by increased virus titers and extensive vascular leakage which eventually led to the animals’ death. However, as dengue occurs in immune competent individuals, we sought to reproduce this mouse model in a less immunocompromised background. Here, we report an ADE model that is mediated by maternal antibodies in type I IFN receptor-deficient A129 mice. We show that 5-week old A129 mice born to DENV1-immune mothers succumbed to a DENV2 infection within 4 days that was sub-lethal in mice born to naïve mothers. Clinical manifestations included extensive hepatocyte vacuolation, moderate vascular leakage, lymphopenia, and thrombocytopenia. Anti-TNFα therapy totally protected the mice and correlated with healthy hepatocytes. In contrast, blocking IL-6 did not impact the virus titers or disease outcome. This A129 mouse model of ADE may help dissecting the mechanisms involved in dengue pathogenesis and evaluate the efficacy of vaccine and

  1. Effect of Diets Containing Sucrose vs. D-tagatose in Hypercholesterolemic Mice

    SciTech Connect

    Police, S.; Harris, J; Lodder, R

    2008-01-01

    Effects of functional sweeteners on the development of the metabolic syndrome and atherosclerosis are unknown. The objective was to compare the effect of dietary carbohydrate in the form of sucrose (SUCR) to D-tagatose (TAG; an isomer of fructose currently used as a low-calorie sweetener) on body weight, blood cholesterol concentrations, hyperglycemia, and atherosclerosis in low-density lipoprotein receptor deficient (LDLr-/-) mice. LDLr-/- male and female mice were fed either standard murine diet or a diet enriched with TAG or SUCR as carbohydrate sources for 16 weeks. TAG and SUCR diets contained equivalent amounts (g/kg) of protein, fat, and carbohydrate. We measuredmore » food intake, body weight, adipocyte diameter, serum cholesterol and lipoprotein concentrations, and aortic atherosclerosis. Macrophage immunostaining and collagen content were examined in aortic root lesions. CONTROL and TAG-fed mice exhibited similar energy intake, body weights and blood glucose and insulin concentrations, but SUCR-fed mice exhibited increased energy intake and became obese and hyperglycemic. Adipocyte diameter increased in female SUCR-fed mice compared to TAG and CONTROL. Male and female SUCR-fed mice had increased serum cholesterol and triglyceride concentrations compared to TAG and CONTROL. Atherosclerosis was increased in SUCR-fed mice of both genders compared to TAG and CONTROL. Lesions from SUCR-fed mice exhibited pronounced macrophage immunostaining and reductions in collagen content compared to TAG and CONTROL mice. These results demonstrate that in comparison to sucrose, equivalent substitution of TAG as dietary carbohydrate does not result in the same extent of obesity, hyperglycemia, hyperlipidemia, and atherosclerosis.« less

  2. Effect of diets containing sucrose vs. D-tagatose in hypercholesterolemic mice.

    PubMed

    Police, Sara B; Harris, J Clay; Lodder, Robert A; Cassis, Lisa A

    2009-02-01

    Effects of functional sweeteners on the development of the metabolic syndrome and atherosclerosis are unknown. The objective was to compare the effect of dietary carbohydrate in the form of sucrose (SUCR) to D-tagatose (TAG; an isomer of fructose currently used as a low-calorie sweetener) on body weight, blood cholesterol concentrations, hyperglycemia, and atherosclerosis in low-density lipoprotein receptor deficient (LDLr(-/-)) mice. LDLr(-/-) male and female mice were fed either standard murine diet or a diet enriched with TAG or SUCR as carbohydrate sources for 16 weeks. TAG and SUCR diets contained equivalent amounts (g/kg) of protein, fat, and carbohydrate. We measured food intake, body weight, adipocyte diameter, serum cholesterol and lipoprotein concentrations, and aortic atherosclerosis. Macrophage immunostaining and collagen content were examined in aortic root lesions. CONTROL and TAG-fed mice exhibited similar energy intake, body weights and blood glucose and insulin concentrations, but SUCR-fed mice exhibited increased energy intake and became obese and hyperglycemic. Adipocyte diameter increased in female SUCR-fed mice compared to TAG and CONTROL. Male and female SUCR-fed mice had increased serum cholesterol and triglyceride concentrations compared to TAG and CONTROL. Atherosclerosis was increased in SUCR-fed mice of both genders compared to TAG and CONTROL. Lesions from SUCR-fed mice exhibited pronounced macrophage immunostaining and reductions in collagen content compared to TAG and CONTROL mice. These results demonstrate that in comparison to sucrose, equivalent substitution of TAG as dietary carbohydrate does not result in the same extent of obesity, hyperglycemia, hyperlipidemia, and atherosclerosis.

  3. Effect of Diets Containing Sucrose vs. D-tagatose in Hypercholesterolemic Mice

    PubMed Central

    Police, Sara B.; Harris, J. Clay; Lodder, Robert A.; Cassis, Lisa A.

    2010-01-01

    Effects of functional sweeteners on the development of the metabolic syndrome and atherosclerosis are unknown. The objective was to compare the effect of dietary carbohydrate in the form of sucrose (SUCR) to D-tagatose (TAG; an isomer of fructose currently used as a low-calorie sweetener) on body weight, blood cholesterol concentrations, hyperglycemia, and atherosclerosis in low-density lipoprotein receptor deficient (LDLr−/−) mice. LDLr−/− male and female mice were fed either standard murine diet or a diet enriched with TAG or SUCR as carbohydrate sources for 16 weeks. TAG and SUCR diets contained equivalent amounts (g/kg) of protein, fat, and carbohydrate. We measured food intake, body weight, adipocyte diameter, serum cholesterol and lipoprotein concentrations, and aortic atherosclerosis. Macrophage immunostaining and collagen content were examined in aortic root lesions. CONTROL and TAG-fed mice exhibited similar energy intake, body weights and blood glucose and insulin concentrations, but SUCR-fed mice exhibited increased energy intake and became obese and hyperglycemic. Adipocyte diameter increased in female SUCR-fed mice compared to TAG and CONTROL. Male and female SUCR-fed mice had increased serum cholesterol and triglyceride concentrations compared to TAG and CONTROL. Atherosclerosis was increased in SUCR-fed mice of both genders compared to TAG and CONTROL. Lesions from SUCR-fed mice exhibited pronounced macrophage immunostaining and reductions in collagen content compared to TAG and CONTROL mice. These results demonstrate that in comparison to sucrose, equivalent substitution of TAG as dietary carbohydrate does not result in the same extent of obesity, hyperglycemia, hyperlipidemia, and atherosclerosis. PMID:19008872

  4. Immunization with Th-CTL fusion peptide and cytosine-phosphate-guanine DNA in transgenic HLA-A2 mice induces recognition of HIV-infected T cells and clears vaccinia virus challenge.

    PubMed

    Daftarian, Pirouz; Ali, Saima; Sharan, Rahul; Lacey, Simon F; La Rosa, Corinna; Longmate, Jeff; Buck, Christopher; Siliciano, Robert F; Diamond, Don J

    2003-10-15

    We evaluated immunogenicity of a novel Th-CTL fusion peptide composed of the pan DR Th epitope and a CTL epitope derived from HIV-pol in two transgenic HLA-A*0201/K(b) mouse models. The immunogenicity of peptides of this structure is highly dependent on coadministered cytosine-phosphate-guanine DNA. Initial evaluations of peptide-specific immunity are based on results of chromium release assay, intracellular cytokine, and tetramer staining. Significant cytotoxic T cell responses are found upon a single immunization with as low as 0.1 nmol both peptide and cytosine-phosphate-guanine DNA. Splenocytes from immunized mice recognize naturally processed HIV-pol expressed from vaccinia virus (pol-VV). Translation of immunologic criteria into more relevant assays was pursued using systemic challenge of immunized mice with pol-VV. Only mice receiving both peptide and DNA together successfully cleared upward of 6 logs of virus from ovaries, compared with controls. Challenge with pol-VV by intranasal route of intranasal immunized mice showed a significant reduction in the levels of VV in lung compared with naive mice. A convincing demonstration of the relevance of these vaccines is the robust lysis of HIV-infected Jurkat T cells (JA2/R7/Hyg) by immune splenocytes from peptide- and DNA-immunized mice. This surprisingly effective immunization merits consideration for clinical evaluation, because it succeeded in causing immune recognition and lysis of cells infected with its target virus and reduction in titer of highly pathogenic VV.

  5. The effect of gastric inhibitory polypeptide on intestinal glucose absorption and intestinal motility in mice

    SciTech Connect

    Ogawa, Eiichi; Hosokawa, Masaya; Faculty of Human Sciences, Tezukayama Gakuin University, Osaka

    2011-01-07

    Research highlights: {yields} Exogenous GIP inhibits intestinal motility through a somatostatin-mediated pathway. {yields} Exogenous GIP inhibits intestinal glucose absorption by reducing intestinal motility. {yields} The GIP-receptor-mediated action in intestine does not involve in GLP-1-mediated pathway. -- Abstract: Gastric inhibitory polypeptide (GIP) is released from the small intestine upon meal ingestion and increases insulin secretion from pancreatic {beta} cells. Although the GIP receptor is known to be expressed in small intestine, the effects of GIP in small intestine are not fully understood. This study was designed to clarify the effect of GIP on intestinal glucose absorption and intestinal motility. Intestinal glucosemore » absorption in vivo was measured by single-pass perfusion method. Incorporation of [{sup 14}C]-glucose into everted jejunal rings in vitro was used to evaluate the effect of GIP on sodium-glucose co-transporter (SGLT). Motility of small intestine was measured by intestinal transit after oral administration of a non-absorbed marker. Intraperitoneal administration of GIP inhibited glucose absorption in wild-type mice in a concentration-dependent manner, showing maximum decrease at the dosage of 50 nmol/kg body weight. In glucagon-like-peptide-1 (GLP-1) receptor-deficient mice, GIP inhibited glucose absorption as in wild-type mice. In vitro examination of [{sup 14}C]-glucose uptake revealed that 100 nM GIP did not change SGLT-dependent glucose uptake in wild-type mice. After intraperitoneal administration of GIP (50 nmol/kg body weight), small intestinal transit was inhibited to 40% in both wild-type and GLP-1 receptor-deficient mice. Furthermore, a somatostatin receptor antagonist, cyclosomatostatin, reduced the inhibitory effect of GIP on both intestinal transit and glucose absorption in wild-type mice. These results demonstrate that exogenous GIP inhibits intestinal glucose absorption by reducing intestinal motility through a

  6. CD40 deficiency in mice exacerbates obesity-induced adipose tissue inflammation, hepatic steatosis, and insulin resistance.

    PubMed

    Guo, Chang-An; Kogan, Sophia; Amano, Shinya U; Wang, Mengxi; Dagdeviren, Sezin; Friedline, Randall H; Aouadi, Myriam; Kim, Jason K; Czech, Michael P

    2013-05-01

    The pathophysiology of obesity and type 2 diabetes in rodents and humans is characterized by low-grade inflammation in adipose tissue and liver. The CD40 receptor and its ligand CD40L initiate immune cell signaling promoting inflammation, but conflicting data on CD40L-null mice confound its role in obesity-associated insulin resistance. Here, we demonstrate that CD40 receptor-deficient mice on a high-fat diet display the expected decrease in hepatic cytokine levels but paradoxically exhibit liver steatosis, insulin resistance, and glucose intolerance compared with their age-matched wild-type controls. Hyperinsulinemic-euglycemic clamp studies also demonstrated insulin resistance in glucose utilization by the CD40-null mice compared with wild-type mice. In contrast to liver, adipose tissue in CD40-deficient animals harbors elevated cytokine levels and infiltration of inflammatory cells, particularly macrophages and CD8(+) effector T cells. In addition, ex vivo explants of epididymal adipose tissue from CD40(-/-) mice display elevated basal and isoproterenol-stimulated lipolysis, suggesting a potential increase of lipid efflux from visceral fat to the liver. These findings reveal that 1) CD40-null mice represent an unusual model of hepatic steatosis with reduced hepatic inflammation, and 2) CD40 unexpectedly functions in adipose tissue to attenuate its inflammation in obesity, thereby protecting against hepatic steatosis.

  7. Selective HDL-Raising Human Apo A-I Gene Therapy Counteracts Cardiac Hypertrophy, Reduces Myocardial Fibrosis, and Improves Cardiac Function in Mice with Chronic Pressure Overload

    PubMed Central

    Amin, Ruhul; Muthuramu, Ilayaraja; Aboumsallem, Joseph Pierre; Mishra, Mudit; Jacobs, Frank; De Geest, Bart

    2017-01-01

    Epidemiological studies support an independent inverse association between high-density lipoprotein (HDL) cholesterol levels and heart failure incidence. The effect of selective HDL-raising adeno-associated viral serotype 8-human apolipoprotein (apo) A-I (AAV8-A-I) gene transfer on cardiac remodeling induced by transverse aortic constriction (TAC) was evaluated in C57BL/6 low-density lipoprotein receptor-deficient mice. Septal wall thickness and cardiomyocyte cross-sectional area were reduced by 16.5% (p < 0.001) and by 13.8% (p < 0.01), respectively, eight weeks after TAC in AAV8-A-I mice (n = 24) compared to control mice (n = 39). Myocardial capillary density was 1.11-fold (p < 0.05) higher and interstitial cardiac fibrosis was 45.3% (p < 0.001) lower in AAV8-A-I TAC mice than in control TAC mice. Lung weight and atrial weight were significantly increased in control TAC mice compared to control sham mice, but were not increased in AAV8-A-I TAC mice. The peak rate of isovolumetric contraction was 1.19-fold (p < 0.01) higher in AAV8-A-I TAC mice (n = 17) than in control TAC mice (n = 29). Diastolic function was also significantly enhanced in AAV8-A-I TAC mice compared to control TAC mice. Nitro-oxidative stress and apoptosis were significantly reduced in the myocardium of AAV8-A-I TAC mice compared to control TAC mice. In conclusion, selective HDL-raising human apo A-I gene transfer potently counteracts the development of pressure overload-induced cardiomyopathy. PMID:28930153

  8. Selective HDL-Raising Human Apo A-I Gene Therapy Counteracts Cardiac Hypertrophy, Reduces Myocardial Fibrosis, and Improves Cardiac Function in Mice with Chronic Pressure Overload.

    PubMed

    Amin, Ruhul; Muthuramu, Ilayaraja; Aboumsallem, Joseph Pierre; Mishra, Mudit; Jacobs, Frank; De Geest, Bart

    2017-09-20

    Epidemiological studies support an independent inverse association between high-density lipoprotein (HDL) cholesterol levels and heart failure incidence. The effect of selective HDL-raising adeno-associated viral serotype 8-human apolipoprotein (apo) A-I (AAV8-A-I) gene transfer on cardiac remodeling induced by transverse aortic constriction (TAC) was evaluated in C57BL/6 low-density lipoprotein receptor-deficient mice. Septal wall thickness and cardiomyocyte cross-sectional area were reduced by 16.5% ( p < 0.001) and by 13.8% ( p < 0.01), respectively, eight weeks after TAC in AAV8-A-I mice ( n = 24) compared to control mice ( n = 39). Myocardial capillary density was 1.11-fold ( p < 0.05) higher and interstitial cardiac fibrosis was 45.3% ( p < 0.001) lower in AAV8-A-I TAC mice than in control TAC mice. Lung weight and atrial weight were significantly increased in control TAC mice compared to control sham mice, but were not increased in AAV8-A-I TAC mice. The peak rate of isovolumetric contraction was 1.19-fold ( p < 0.01) higher in AAV8-A-I TAC mice ( n = 17) than in control TAC mice ( n = 29). Diastolic function was also significantly enhanced in AAV8-A-I TAC mice compared to control TAC mice. Nitro-oxidative stress and apoptosis were significantly reduced in the myocardium of AAV8-A-I TAC mice compared to control TAC mice. In conclusion, selective HDL-raising human apo A-I gene transfer potently counteracts the development of pressure overload-induced cardiomyopathy.

  9. Low-protein diet improves blood and urinary glucose levels and renal manifestations of diabetes in C57BLKS-db/db mice.

    PubMed

    Arimura, Emi; Horiuchi, Masahisa; Kawaguchi, Hiroaki; Miyoshi, Noriaki; Aoyama, Kohji; Takeuchi, Toru

    2013-03-01

    Dietary protein content is related clinically to the development of diabetic nephropathy. Here, we investigated how dietary protein content (12-24 % energy) within the range used by humans affected renal manifestations including the expressions of genes involved in the renin-angiotensin (RA) system in control and diabetic mice. Moreover, we examined the effects of dietary protein content on HbA1c and urinary glucose. Control (CT) and leptin receptor-deficient obese (db) mice, 5 weeks old, were fed the diets below. Under ad libitum conditions, mice were fed 12, 18, and 24 % energy from protein (L-, M-, and H-diets) for 8 weeks. Under pair-feeding conditions, db mice were supplied H-diet (db-Hp) to the equivalent energy to that consumed by db-L mice. Renal manifestations and values related to glucose and insulin were examined biochemically and pathologically. Under ad libitum conditions, db mice consumed food and water dose dependently of the dietary protein content, although they were consumed similarly by CT mice. CT-L mice showed lower urinary albumin and kidney weight, in association with lower mRNA levels of angiotensinogen and renin, than CT-H mice. Under pair-feeding conditions, db-L mice showed a lower ratio of kidney/body weight, HbA1(C), and urinary glucose, and a higher β-cell distribution rate in the pancreas than db-Hp mice. Low-protein intake in the range used by humans may relieve renal manifestations through the suppressed expression of genes in the renal RA system of CT mice. On the other hand, in db mice, low-protein intake improved hyperglycemia and the renal manifestations of diabetes.

  10. Critical role of IFN-gamma in CFA-mediated protection of NOD mice from diabetes development.

    PubMed

    Mori, Yoshiko; Kodaka, Tetsuro; Kato, Takako; Kanagawa, Edith M; Kanagawa, Osami

    2009-11-01

    IFN-gamma signaling-deficient non-obese diabetic (NOD) mice develop diabetes with similar kinetics to those of wild-type NOD mice. However, the immunization of IFN-gamma signaling-deficient NOD mice with CFA failed to induce long-term protection, whereas wild-type NOD mice receiving CFA remained diabetes-free. CFA also failed to protect IFN-gamma receptor-deficient (IFN-gammaR(-/-)) NOD mice from the autoimmune rejection of transplanted islets, as it does in diabetic NOD mice, and from disease transfer by spleen cells from diabetic NOD mice. These data clearly show that the pro-inflammatory cytokine IFN-gamma is necessary for the CFA-mediated protection of NOD mice from diabetes. There is no difference in the T(h)1/T(h)17 balance between IFN-gammaR(-/-) NOD and wild-type NOD mice. There is also no difference in the total numbers and percentages of regulatory T (Treg) cells in the lymph node CD4(+) T-cell populations between IFN-gammaR(-/-) NOD and wild-type NOD mice. However, pathogenic T cells lacking IFN-gammaR are resistant to the suppressive effect of Treg cells, both in vivo and in vitro. Therefore, it is likely that CFA-mediated protection against diabetes development depends on a change in the balance between Treg cells and pathogenic T cells, and IFN-gamma signaling seems to control the susceptibility of pathogenic T cells to the inhibitory activity of Treg cells.

  11. Mice lacking D5 dopamine receptors have increased sympathetic tone and are hypertensive.

    PubMed

    Hollon, Tom R; Bek, Martin J; Lachowicz, Jean E; Ariano, Marjorie A; Mezey, Eva; Ramachandran, Ramesh; Wersinger, Scott R; Soares-da-Silva, Patricio; Liu, Zhi Fang; Grinberg, Alexander; Drago, John; Young, W Scott; Westphal, Heiner; Jose, Pedro A; Sibley, David R

    2002-12-15

    Dopamine is an important transmitter in the CNS and PNS, critically regulating numerous neuropsychiatric and physiological functions. These actions of dopamine are mediated by five distinct receptor subtypes. Of these receptors, probably the least understood in terms of physiological functions is the D5 receptor subtype. To better understand the role of the D5 dopamine receptor (DAR) in normal physiology and behavior, we have now used gene-targeting technology to create mice that lack this receptor subtype. We find that the D5 receptor-deficient mice are viable and fertile and appear to develop normally. No compensatory alterations in other dopamine receptor subtypes were observed. We find, however, that the mutant mice develop hypertension and exhibit significantly elevated blood pressure (BP) by 3 months of age. This hypertension appears to be caused by increased sympathetic tone, primarily attributable to a CNS defect. Our data further suggest that this defect involves an oxytocin-dependent sensitization of V1 vasopressin and non-NMDA glutamatergic receptor-mediated pathways, potentially within the medulla, leading to increased sympathetic outflow. These results indicate that D5 dopamine receptors modulate neuronal pathways regulating blood pressure responses and may provide new insights into mechanisms for some forms of essential hypertension in humans, a disease that afflicts up to 25% of the aged adult population in industrialized societies.

  12. Chronic administration of the soluble, nonbacterial fraction of kefir attenuates lipid deposition in LDLr-/-mice.

    PubMed

    Santanna, Adriélly F; Filete, Placielle F; Lima, Ewelyne M; Porto, Marcella L; Meyrelles, Silvana S; Vasquez, Elisardo C; Endringer, Denise C; Lenz, Dominik; Abdalla, Dulcineia S P; Pereira, Thiago M C; Andrade, Tadeu U

    2017-03-01

    Kefir is obtained by the action of acidic bacteria and yeasts that exist in symbiotic association in kefir grains. Recently, this fermented milk drink has been recommended for the treatment of several clinical conditions, such as inflammatory, gastrointestinal, or cardiovascular-related diseases, or a combination of these diseases. However, its effects on atherosclerosis are not yet clear. The aim of this study was to prove that chronic treatment with a soluble, nonbacterial fraction of kefir could reduce the progression of atherosclerosis in low-density lipoprotein receptor-deficient (LDLr -/- ) mice. LDLr -/- mice were divided into four groups as follows: RESULTS: The soluble, nonbacterial fraction of kefir reduced lipid deposition (P < 0.05) independent of hypercholesterolemia. Moreover, kefir was capable of diminishing the circulating proinflammatory intereukin (IL)-6 level and the ratio of tumor necrosis factor-α to IL-10 (50% and 42%, P < 0.05, respectively) and augmenting the antiinflammatory IL-10 level by approximately 74% (P < 0.05). Chronic treatment with a soluble nonbacterial fraction of kefir was able to decrease the lipid deposition in LDLr -/- hypercholesteremic mice, at least in part through modifying the circulating cytokine profile. The beneficial effects of kefir provide new perspectives for its use as an adjuvant in the prevention of atherosclerosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Effects of low-intensity pulsed electromagnetic fields on bone microarchitecture, mechanical strength and bone turnover in type 2 diabetic db/db mice.

    PubMed

    Li, Jianjun; Zeng, Zhaobin; Zhao, Yantao; Jing, Da; Tang, Chuhua; Ding, Yin; Feng, Xue

    2017-09-07

    Type 2 diabetic patients have impaired bone quality, leading to increased fracture risk. Substantial evidence demonstrates that pulsed electromagnetic fields (PEMF) could resist osteopenia/osteoporosis induced by estrogen deficiency and disuse. However, the effects of PEMF on osteopenia/osteoporosis associated with diabetes, especially for more prevalent type 2 diabetes, remain poorly understood. We herein investigated the skeletal effects and mechanisms of PEMF (15 Hz, 20 Gs) on leptin receptor-deficient db/db mice with typical type 2 diabetic symptoms. Our µCT results showed that 12-week PEMF exposure significantly improved both cancellous and cortical bone microarchitecture in db/db mice. Three-point bending and biomechanical indentation testing demonstrated that PEMF improved whole-bone structural properties and tissue-level material properties in db/db mice. PEMF significantly promoted bone formation in db/db mice evidenced by increased serum osteocalcin and bone mineral apposition rate, whereas PEMF exerted no observable alteration in bone resorption. Real-time PCR showed that PEMF upregulated tibial gene expression of osteoblastogenesis-related of canonical Wnt/β-catenin signaling but not osteoclastogenesis-related RANKL-RANK signaling in db/db mice. Our findings demonstrate that PEMF improved bone quantity and quality with obvious anabolic activities in db/db mice, and imply that PEMF might become a clinically applicable treatment modality for improving bone quality in type 2 diabetic patients.

  14. Deteriorated glucose metabolism with a high-protein, low-carbohydrate diet in db mice, an animal model of type 2 diabetes, might be caused by insufficient insulin secretion.

    PubMed

    Arimura, Emi; Pulong, Wijang Pralampita; Marchianti, Ancah Caesarina Novi; Nakakuma, Miwa; Abe, Masaharu; Ushikai, Miharu; Horiuchi, Masahisa

    2017-02-01

    We previously showed the deleterious effects of increased dietary protein on renal manifestations and glucose metabolism in leptin receptor-deficient (db) mice. Here, we further examined its effects on glucose metabolism, including urinary C-peptide. We also orally administered mixtures corresponding to low- or high-protein diets to diabetic mice. In diet experiments, under pair-feeding (equivalent energy and fat) conditions using a metabolic cage, mice were fed diets with different protein content (L diet: 12 % protein, 71 % carbohydrate, 17 % fat; H diet: 24 % protein, 59 % carbohydrate, 17 % fat) for 15 days. In oral administration experiments, the respective mixtures (L mixture: 12 % proline, 71 % maltose or starch, 17 % linoleic acid; H mixture: 24 % proline, 59 % maltose or starch, 17 % linoleic acid) were supplied to mice. Biochemical parameters related to glucose metabolism were measured. The db-H diet mice showed significantly higher water intake, urinary volume, and glucose levels than db-L diet mice but similar levels of excreted urinary C-peptide. In contrast, control-H diet mice showed significantly higher C-peptide excretion than control-L diet mice. Both types of mice fed H diet excreted high levels of urinary albumin. When maltose mixtures were administered, db-L mixture mice showed significantly higher blood glucose after 30 min than db-H mixture mice. However, db mice administered starch-H mixture showed significantly higher blood glucose 120-300 min post-administration than db-L mixture mice, although both groups exhibited similar insulin levels. High-protein, low-carbohydrate diets deteriorated diabetic conditions and were associated with insufficient insulin secretion in db mice. Our findings may have implications for dietary management of diabetic symptoms in human patients.

  15. Impact of high-fat diet and voluntary running on body weight and endothelial function in LDL receptor knockout mice.

    PubMed

    Langbein, Heike; Hofmann, Anja; Brunssen, Coy; Goettsch, Winfried; Morawietz, Henning

    2015-05-01

    Obesity and physical inactivity are important cardiovascular risk factors. Regular physical exercise has been shown to mediate beneficial effects in the prevention of cardiovascular diseases. However, the impact of physical exercise on endothelial function in proatherosclerotic low-density lipoprotein receptor deficient (LDLR(-/-)) mice has not been studied so far. Six-week-old male LDLR(-/-) mice were fed a standard diet or a high-fat diet (39 kcal% fat diet) for 20 weeks. The impact of high-fat diet and voluntary running on body weight and amount of white adipose tissue was monitored. Basal tone and endothelial function was investigated in aortic rings using a Mulvany myograph. LDLR(-/-) mice on high-fat diet had increased cumulative food energy intake, but also higher physical activity compared to mice on control diet. Body weight and amount of visceral and retroperitoneal white adipose tissue of LDLR(-/-) mice were significantly increased by high-fat diet and partially reduced by voluntary running. Endothelial function in aortae of LDLR(-/-) mice was impaired after 20 weeks on standard and high-fat diet and could not be improved by voluntary running. Basal tone showed a trend to be increased by high-fat diet. Voluntary running reduced body weight and amount of white adipose tissue in LDLR(-/-) mice. Endothelial dysfunction in LDLR(-/-) mice could not be improved by voluntary running. In a clinical context, physical exercise alone might not have an influence on functional parameters and LDL-C levels in patients with familial hypercholesterolemia. However, physical activity in these patients may be in general beneficial and should be performed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. Mercury modulates the cytochrome P450 1a1, 1a2 and 1b1 in C57BL/6J mice: in vivo and in vitro studies

    SciTech Connect

    Amara, Issa E.A.; Anwar-Mohamed, Anwar; Abdelhamid, Ghada

    2013-02-01

    In the current study C57BL/6J mice were injected intraperitoneally with Hg{sup 2+} in the absence and presence of TCDD. After 6 and 24 h the liver was harvested and the expression of Cyps was determined. In vitro, isolated hepatocytes were incubated with TCDD in the presence and absence of Hg{sup 2+}. At the in vivo level, Hg{sup 2+} significantly decreased the TCDD-mediated induction of Cyps at 6 h while potentiating their levels at 24 h. In vitro, Hg{sup 2+} significantly inhibited the TCDD-mediated induction of Cyp1a1 in a concentration- and time-dependent manner. Interestingly, Hg{sup 2+} increased the serum hemoglobin (Hb)more » levels in mice treated for 24 h. Upon treatment of isolated hepatocytes with Hb alone, there was an increase in the AhR-dependent luciferase activity with a subsequent increase in Cyp1a1 protein and catalytic activity levels. Importantly, when hepatocytes were treated for 2 h with Hg{sup 2+} in the presence of TCDD, then the medium was replaced with new medium containing Hb, there was potentiation of the TCDD-mediated effect. In addition, Hg{sup 2+} increased heme oxygenase-1 (HO-1) mRNA, which coincided with a decrease in the Cyp1a1 activity level. When the competitive HO-1 inhibitor, tin mesoporphyrin was applied to the hepatocytes there was a partial restoration of Hg{sup 2+}-mediated inhibition of Cyp1a1 activity. In conclusion, we demonstrate for the first time that there is a differential modulation of the TCDD-mediated induction of Cyp1a1 by Hg{sup 2+} in C57BL/6J mice livers and isolated hepatocytes. Moreover, this study implicates Hb as an in vivo specific modulator of Cyp1 family. -- Highlights: ► In vivo, Hg{sup 2+} decreased the Cyps at 6 h while potentiating their levels at 24 h. ► In vitro, Hg{sup 2+} significantly inhibited the TCDD-mediated induction of Cyps. ► Hg{sup 2+} increased the serum Hb levels in animals treated for 24 h. ► Hb potentiated the TCDD-mediated effect on Cyps. ► Tin mesoporphyrin

  17. Role of light and the circadian clock in the rhythmic oscillation of intraocular pressure: Studies in VPAC2 receptor and PACAP deficient mice.

    PubMed

    Fahrenkrug, Jan; Georg, Birgitte; Hannibal, Jens; Jørgensen, Henrik Løvendahl

    2018-04-01

    The intraocular pressure of mice displays a daily rhythmicity being highest during the dark period. The present study was performed to elucidate the role of the circadian clock and light in the diurnal and the circadian variations in intraocular pressure in mice, by using animals with disrupted clock function (VPAC2 receptor knockout mice) or impaired light information to the clock (PACAP knockout mice). In wildtype mice, intraocular pressure measured under light/dark conditions showed a statistically significant 24 h sinusoidal rhythm with nadir during the light phase and peak during the dark phase. After transfer of the wildtype mice into constant darkness, the intraocular pressure increased, but the rhythmic changes in intraocular pressure continued with a pattern identical to that obtained during the light/dark cycle. The intraocular pressure in VPAC2 receptor deficient mice during light/dark conditions also showed a sinusoidal pattern with significant changes as a function of a 24 h cycle. However, transfer of the VPAC2 receptor knockout mice into constant darkness completely abolished the rhythmic changes in intraocular pressure. The intraocular pressure in PACAP deficient mice oscillated significantly during both 24 h light and darkness and during constant darkness. During LD conditions, the amplitude of PACAP deficient was significantly lower compared to wildtype mice, resulting in higher daytime and lower nighttime values. In conclusion, by studying the VPAC2 receptor knockout mouse which lacks circadian control and the PACAP knockout mouse which displays impaired light signaling, we provided evidence that the daily intraocular pressure rhythms are primarily generated by the circadian master clock and to a lesser extent by environmental light and darkness. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. The peroxisome proliferator activated receptor gamma (PPARgamma) ligand rosiglitazone modulates bronchoalveolar lavage levels of leptin, adiponectin, and inflammatory cytokines in lean and obese mice.

    PubMed

    Holguin, Fernando; Rojas, Mauricio; Hart, C Michael

    2007-12-01

    Obese mice that lack leptin receptor (db (-) /db (-)) have been shown to have innate bronchial hyperresponsiveness (BHR). It has been proposed that the obesity-mediated BHR may involve a combination of increased leptin and reduced systemic adiponectin levels. The aim of this study was to determine if obesity modifies the airway concentration of leptin and adiponectin and whether treatment with a synthetic peroxisome proliferator-activated receptor gamma (PPARgamma) ligand can reduce airway leptin and increase airway adiponectin. In this study, obese, leptin receptor-deficient (db (-) /db (-)), or lean (db ( + ) /db (-)) mice were treated with rosiglitazone (3 mg/kg/day) or vehicle by gavage daily for 1 week. Bronchioalveolar lavage (BAL) was subsequently performed to determine levels of leptin, adiponectin, and inflammatory cytokines. Treatment with rosiglitazone increased BAL adiponectin levels in lean (p = 0.04) and to a lesser extent in obese mice (p = 0.07). Rosiglitazone treatment lowered leptin levels in lean mice, but increased leptin levels in BAL fluid of obese mice (p < 0.01). The BAL levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) were lower in the lean rosiglitazone-treated group compared with the obese vehicle-treated group and lower in the obese rosiglitazone-treated group compared with the obese vehicle-treated group. These results demonstrate that obesity is associated with alterations in adipokine and cytokine levels in the airways that can be modulated by treatment with roziglitazone.

  19. Ursolic acid protects diabetic mice against monocyte dysfunction and accelerated atherosclerosis.

    PubMed

    Ullevig, Sarah L; Zhao, Qingwei; Zamora, Debora; Asmis, Reto

    2011-12-01

    Accelerated atherosclerosis is a major diabetic complication initiated by the enhanced recruitment of monocytes into the vasculature. In this study, we examined the therapeutic potential of the phytonutrients ursolic acid (UA) and resveratrol (RES) in preventing monocyte recruitment and accelerated atherosclerosis. Dietary supplementation with either RES or UA (0.2%) protected against accelerated atherosclerosis induced by streptozotocin in high-fat diet-fed LDL receptor-deficient mice. However, mice that received dietary UA for 11 weeks were significantly better protected and showed a 53% reduction in lesion formation while mice fed a RES-supplemented diet showed only a 31% reduction in lesion size. Importantly, UA was also significantly more effective in preventing the appearance of proinflammatory GR-1(high) monocytes induced by these diabetic conditions and reducing monocyte recruitment into MCP-1-loaded Matrigel plugs implanted into these diabetic mice. Oxidatively stressed THP-1 monocytes mimicked the behavior of blood monocytes in diabetic mice and showed enhanced responsiveness to monocyte chemoattractant protein-1 (MCP-1) without changing MCP-1 receptor (CCR2) surface expression. Pretreatment of THP-1 monocytes with RES or UA (0.3-10μM) for 15h resulted in the dose-dependent inhibition of H(2)O(2)-accelerated chemotaxis in response to MCP-1, but with an IC(50) of 0.4μM, UA was 2.7-fold more potent than RES. Dietary UA is a potent inhibitor of monocyte dysfunction and accelerated atherosclerosis induced by diabetes. These studies identify ursolic acid as a potential therapeutic agent for the treatment of diabetic complications, including accelerated atherosclerosis, and provide a novel mechanism for the anti-atherogenic properties of ursolic acid. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  20. Dapagliflozin-lowered blood glucose reduces respiratory Pseudomonas aeruginosa infection in diabetic mice.

    PubMed

    Åstrand, Annika; Wingren, Cecilia; Benjamin, Audra; Tregoning, John S; Garnett, James P; Groves, Helen; Gill, Simren; Orogo-Wenn, Maria; Lundqvist, Anders J; Walters, Dafydd; Smith, David M; Taylor, John D; Baker, Emma H; Baines, Deborah L

    2017-05-01

    Hyperglycaemia increases glucose concentrations in airway surface liquid and increases the risk of pulmonary Pseudomonas aeruginosa infection. We determined whether reduction of blood and airway glucose concentrations by the anti-diabetic drug dapagliflozin could reduce P. aeruginosa growth/survival in the lungs of diabetic mice. The effect of dapagliflozin on blood and airway glucose concentration, the inflammatory response and infection were investigated in C57BL/6J (wild type, WT) or leptin receptor-deficient (db/db) mice, treated orally with dapagliflozin prior to intranasal dosing with LPS or inoculation with P. aeruginosa. Pulmonary glucose transport and fluid absorption were investigated in Wistar rats using the perfused fluid-filled lung technique. Fasting blood, airway glucose and lactate concentrations were elevated in the db/db mouse lung. LPS challenge increased inflammatory cells in bronchoalveolar lavage fluid from WT and db/db mice with and without dapagliflozin treatment. P. aeruginosa colony-forming units (CFU) were increased in db/db lungs. Pretreatment with dapagliflozin reduced blood and bronchoalveolar lavage glucose concentrations and P. aeruginosa CFU in db/db mice towards those seen in WT. Dapagliflozin had no adverse effects on the inflammatory response in the mouse or pulmonary glucose transport or fluid absorption in the rat lung. Pharmacological lowering of blood glucose with dapagliflozin effectively reduced P. aeruginosa infection in the lungs of diabetic mice and had no adverse pulmonary effects in the rat. Dapagliflozin has potential to reduce the use, or augment the effect, of antimicrobials in the prevention or treatment of pulmonary infection. © 2017 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.

  1. Wild rice (Zizania palustris L.) prevents atherogenesis in LDL receptor knockout mice.

    PubMed

    Surendiran, Gangadaran; Goh, Chunyan; Le, Khuong; Zhao, Zhaohui; Askarian, Fatemeh; Othman, Rgia; Nicholson, Tiffany; Moghadasian, Paymahn; Wang, Ya-Jane; Aliani, Michel; Shen, Garry; Beta, Trust; Moghadasian, Mohammed H

    2013-10-01

    Dietary modifications including healthy eating constitute one of the first line strategies for prevention and treatment of cardiovascular disease (CVD) risk factors including high cholesterol and atherosclerosis. The purpose of the present study was to investigate the potential cardiovascular benefits of wild rice in male and female LDL-receptor-deficient (LDLr-KO) mice. Wild rice was used to create a semi-synthetic diet containing approximately 60% of total energy from carbohydrate. Two other experimental diets were similar in macronutrient composition, but containing either white rice or commercial carbohydrate sources. All diets were supplemented with 0.06% (w/w) dietary cholesterol. The mice were divided into six experimental groups and fed with these diets over 24 weeks. Consumption of wild rice significantly reduced the size and severity of atherosclerotic lesions in the aortic roots of male and female mice by 71 and 61% respectively, compared to the control group of the same gender. This effect was associated with significant reductions of plasma cholesterol levels by 15 and 40%, low density lipoprotein (LDL) levels by 12 and 42%, and very low density lipoprotein (VLDL) levels by 35 and 75% respectively, in male and female mice compared to the control group of the same gender. Increased fecal cholesterol excretion of up to 34% was also noted, compared to the control group of the same gender. However, the antiatherogenic effect of wild rice was not associated with increased superoxide dismutase (SOD) and catalase (CAT) activities. Current data suggest that cholesterol-lowering effects of wild rice may be the main factor for the prevention of atherogenesis in LDLr-KO mice. Additional studies are needed to understand the mechanism of action. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Genetic Dissection of the Role of Cannabinoid Type-1 Receptors in the Emotional Consequences of Repeated Social Stress in Mice

    PubMed Central

    Dubreucq, Sarah; Matias, Isabelle; Cardinal, Pierre; Häring, Martin; Lutz, Beat; Marsicano, Giovanni; Chaouloff, Francis

    2012-01-01

    The endocannabinoid system (ECS) tightly controls emotional responses to acute aversive stimuli. Repeated stress alters ECS activity but the role played by the ECS in the emotional consequences of repeated stress has not been investigated in detail. This study used social defeat stress, together with pharmacology and genetics to examine the role of cannabinoid type-1 (CB1) receptors on repeated stress-induced emotional alterations. Seven daily social defeat sessions increased water (but not food) intake, sucrose preference, anxiety, cued fear expression, and adrenal weight in C57BL/6N mice. The first and the last social stress sessions triggered immediate brain region-dependent changes in the concentrations of the principal endocannabinoids anandamide and 2-arachidonoylglycerol. Pretreatment before each of the seven stress sessions with the CB1 receptor antagonist rimonabant prolonged freezing responses of stressed mice during cued fear recall tests. Repeated social stress abolished the increased fear expression displayed by constitutive CB1 receptor-deficient mice. The use of mutant mice lacking CB1 receptors from cortical glutamatergic neurons or from GABAergic neurons indicated that it is the absence of the former CB1 receptor population that is responsible for the fear responses in socially stressed CB1 mutant mice. In addition, stress-induced hypolocomotor reactivity was amplified by the absence of CB1 receptors from GABAergic neurons. Mutant mice lacking CB1 receptors from serotonergic neurons displayed a higher anxiety but decreased cued fear expression than their wild-type controls. These mutant mice failed to show social stress-elicited increased sucrose preference. This study shows that (i) release of endocannabinoids during stress exposure impedes stress-elicited amplification of cued fear behavior, (ii) social stress opposes the increased fear expression and delayed between-session extinction because of the absence of CB1 receptors from cortical

  3. Platelet-activating factor drives eotaxin production in an allergic pleurisy in mice

    PubMed Central

    Klein, André; Pinho, Vanessa; Alessandrini, Ana Letícia; Shimizu, Takao; Ishii, Satoshi; Teixeira, Mauro M

    2002-01-01

    The activation of eosinophils via G-protein-coupled seven transmembran receptors play a necessary role in the recruitment of these cells into tissue. The present study investigates a role for PAF in driving eotaxin production and eosinophil recruitment in an allergic pleurisy model in mice. The intrapleural injection of increasing doses of PAF (10−11 to 10−9 moles per cavity) induced a dose- and PAF receptor-dependent recruitment of eosinophils 48 h after stimulation. Intrapleural injection of PAF induced the rapid (within 1 h) release of eotaxin into the pleural cavity of mice and an anti-eotaxin antibody effectively inhibited PAF-induced recruitment of eosinophils. Eosinophil recruitment in the allergic pleurisy was markedly inhibited by the PAF receptor antagonist UK-74,505 (modipafant, 1 mg kg−1). Moreover, recruitment of eosinophils in sensitized and challenged PAF receptor-deficient animals was lower than that observed in wild-type animals. Blockade of PAF receptors with UK-74,505 suppressed by 85% the release of eotaxin in the allergic pleurisy. Finally, the injection of a sub-threshold dose of PAF and eotaxin cooperated to induce eosinophil recruitment in vivo. In conclusion, the production of PAF in an allergic reaction could function in multiple ways to facilitate the recruitment of eosinophils  –  by facilitating eotaxin release and by cooperating with eotaxin to induce greater recruitment of eosinophils. PMID:11877329

  4. Impact of Macrophage Toll-Like Receptor 4 Deficiency on Macrophage Infiltration into Adipose Tissue and the Artery Wall in Mice

    PubMed Central

    Coenen, Kimberly R.; Gruen, Marnie L.; Lee-Young, Robert S.; Puglisi, Michael J.; Wasserman, David H.; Hasty, Alyssa H.

    2008-01-01

    Hypothesis Toll-like receptor 4 (TLR4) is a receptor for saturated fatty acids (SFAs) and global deficiency of TLR4 has been shown to protect against inflammation, insulin resistance (IR), and atherosclerotic lesion formation. Because macrophages (Mθs) express TLR4 and are important in IR and atherosclerotic lesion formation due to their infiltration of white adipose tissue (WAT) and the artery wall, respectively, we hypothesized that deficiency of Mθ TLR4 could protect against these disorders. Methods Bone marrow transplantation of agouti, LDL receptor deficient (Ay/a;LDLR-/-) mice with marrow from either C57BL/6 or TLR4-/- mice was performed. Recipient mice with the presence (MθTLR4+/+) or absence (MθTLR4-/-) of Mθ TLR4 were then placed on one of four diets: 1) low fat (LF); 2) high fat (HF); 3) high fat rich in SFAs (HFSFA); and 4) the HFSFA diet supplemented with fish oil (HFSFA+FO). Results There were no differences in body composition or plasma lipids between MθTLR4+/+ and MθTLR4-/- mice on any of the diets. However, there was a decrease in some macrophage and inflammatory markers in WAT of female LF-fed MθTLR4-/- mice compared to MθTLR4+/+ mice. MθTLR4-/- mice fed LF diet also displayed decreased atherosclerotic lesion area. There were no differences in Mθ accrual in WAT or atherosclerosis between MθTLR4+/+ and MθTLR4-/- mice fed any of the high fat diets. Finally, there was no difference in insulin sensitivity between MθTLR4+/+ and MθTLR4-/- mice fed the HFSFA diet. Conclusions These data suggest that under certain dietary conditions, Mθ expression of TLR4 can be an important mediator of Mθ accumulation in both WAT and the artery wall. PMID:19052722

  5. Amygdalin ameliorates the progression of atherosclerosis in LDL receptor‑deficient mice.

    PubMed

    Lv, Jianzhen; Xiong, Wen; Lei, Tiantian; Wang, Hailian; Sun, Minghan; Hao, Erwei; Wang, Zhiping; Huang, Xiaoqi; Deng, Shaoping; Deng, Jiagang; Wang, Yi

    2017-12-01

    Previous studies have demonstrated that regulatory T cells (Tregs) are pivotal in the regulation of T cell‑mediated immune responses in atherosclerosis, a chronic autoimmune‑like disease. In the authors' previous studies, it was demonstrated that amygdalin ameliorated atherosclerosis by the regulation of Tregs in apolipoprotein E‑deficient (ApoE‑/‑) mice. Therefore, the aim of the present study was to investigate the therapeutic effect of amygdalin on low‑density lipoprotein (LDL) receptor deficient (LDLR‑/‑) mice, and to examine its immune regulatory function by the stimulation of Tregs. To establish an atherosclerosis mouse model, the LDLR‑/‑ mice were fed a high fat and high cholesterol diet then the total plasma cholesterol, triglyceride, LDL and chemokines levels were measured by an ELISA. Following sacrificing the mice, the upper sections of the aorta were stained by hematoxylin and eosin, and Oil red O to assess the plaque area. Then western blotting and reverse transcription polymerase chain reactions were performed to analysis the expression levels of cluster of differentiation 68, monocyte chemoattractant protein‑1, matrix metalloproteinase (MMP)‑2, MMP‑9 and forkhead box P3 (Foxp3). To further confirm the activation of FOXP3 by amygdalin, lentiviruses carrying Foxp3 shRNA were injected into the mice, and the serum cytokines levels were measured by ELISA. Following feeding of the mice with a high‑fat/high‑cholesterol diet, the LDLR‑/‑ mice demonstrated comparatively higher levels of triglyceride, total cholesterol and LDL, compared with levels in the amygdalin‑treated mice. By comparing the vessel area, lumen area, plaque area, and percentage aortic plaque coverage, the effects of amygdalin on pre‑existing lesions were assessed. In addition, the levels of CD68, monocyte chemoattractant protein‑1, MMP‑2 and MMP‑9 were analyzed, and analysis of the expression of interleukin (IL)‑1β, IL‑6 and tumor necrosis

  6. The effect of dose on 2,3,7,8-TCDD tissue distribution, metabolism and elimination in CYP1A2(-/_) knockout and C57BL/6N parental strains of mice

    EPA Science Inventory

    Numerous metabolism studies have demonstrated that the toxic contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is poorly metabolized. A hallmark feature of TCDD exposure is induction of hepatic CYP1A2 and subsequent sequestration leading to high liver-to-fat concentration ra...

  7. The Effect of Dose on 2,3,7,8-TCDD Tissue Distribution, Metabolism and Elimination in CYP1A2 (-/-) Knockout and C57BL/6N Parental Strains of Mice

    USDA-ARS?s Scientific Manuscript database

    Numerous metabolism studies have demonstrated that the highly toxic 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is poorly metabolized. A hallmark feature of TCDD exposure is induction of hepatic CYP1A2 and subsequent sequestration leading to high liver to fat concentration ratios. This study was in...

  8. Melatonin Receptor 1 Deficiency Affects Feeding Dynamics and Pro-Opiomelanocortin Expression in the Arcuate Nucleus and Pituitary of Mice.

    PubMed

    Fischer, Claudia; Mueller, Tanja; Pfeffer, Martina; Wicht, Helmut; von Gall, Charlotte; Korf, Horst-Werner

    2017-01-01

    Melatonin, the neurohormone for darkness, mediates photoperiod-dependent changes in physiology and behavior by targeting specific membrane-bound receptors (MT1 and MT2). In the present study, we investigated the impact of MT1 receptor deficiency on feeding behavior, locomotor activity and mRNA expression levels encoding for the polypeptide pro-opiomelanocortin (Pomc) and neuropeptide Y (Npy) in the hypothalamic arcuate nucleus (ARC) and the adenohypophysis [pars distalis (PD) and pars intermedia (PI)] in a comparison between wild-type (WT) and MT1-deficient (MT1-/-) mice. The MT1-/- mice spent significantly more time feeding than the WT mice, while the general locomotor behavior, body weight and the total amount of food consumed did not differ between both genotypes. The nocturnal expression levels of Pomc in the ARC and PD were significantly higher in WT as compared to MT1-/- mice and exogenous melatonin administered during the light phase stimulated Pomc expression in WT mice only. No differences were found between WT and MT1-/- mice with regard to Pomc expression levels in the PI. Thus, the MT1-mediated signaling stimulates Pomc expression in a region-specific pattern. Since the MT1-mediated changes in Pomc expression do not elicit direct orexigenic or anorexigenic effects, such effects are obviously mediated by regulatory systems downstream of the Pomc mRNA (e.g. cleavage and release of POMC derivatives), which are independent of MT1 signaling. © 2016 The Author(s) Published by S. Karger AG, Basel.

  9. Protease-activated receptor 1 and hematopoietic cell tissue factor are required for hepatic steatosis in mice fed a Western diet.

    PubMed

    Kassel, Karen M; Owens, A Phillip; Rockwell, Cheryl E; Sullivan, Bradley P; Wang, Ruipeng; Tawfik, Ossama; Li, Guodong; Guo, Grace L; Mackman, Nigel; Luyendyk, James P

    2011-11-01

    Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of obesity and metabolic syndrome and contributes to increased risk of cardiovascular disease and liver-related morbidity and mortality. Indeed, obese patients with metabolic syndrome generate greater amounts of thrombin, an indication of coagulation cascade activation. However, the role of the coagulation cascade in Western diet-induced NAFLD has not been investigated. Using an established mouse model of Western diet-induced NAFLD, we tested whether the thrombin receptor protease-activated receptor 1 (PAR-1) and hematopoietic cell-derived tissue factor (TF) contribute to hepatic steatosis. In association with hepatic steatosis, plasma thrombin-antithrombin levels and hepatic fibrin deposition increased significantly in C57Bl/6J mice fed a Western diet for 3 months. PAR-1 deficiency reduced hepatic inflammation, particularly monocyte chemoattractant protein-1 expression and macrophage accumulation. In addition, PAR-1 deficiency was associated with reduced steatosis in mice fed a Western diet, including reduced liver triglyceride accumulation and CD36 expression. Similar to PAR-1 deficiency, hematopoietic cell TF deficiency was associated with reduced inflammation and reduced steatosis in livers of low-density lipoprotein receptor-deficient mice fed a Western diet. Moreover, hematopoietic cell TF deficiency reduced hepatic fibrin deposition. These studies indicate that PAR-1 and hematopoietic cell TF are required for liver inflammation and steatosis in mice fed a Western diet. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  10. Cloning Mice.

    PubMed

    Ogura, Atsuo

    2017-08-01

    Viable and fertile mice can be generated by somatic nuclear transfer into enucleated oocytes, presumably because the transplanted somatic cell genome becomes reprogrammed by factors in the oocyte. The first somatic cloned offspring of mice were obtained by directly injecting donor nuclei into recipient enucleated oocytes. When this method is used (the so-called Honolulu method of somatic cell nuclear transfer [SCNT]), the donor nuclei readily and completely condense within the enucleated metaphase II-arrested oocytes, which contain high levels of M-phase-promoting factor (MPF). It is believed that the condensation of the donor chromosomes promotes complete reprogramming of the donor genome within the mouse oocytes. Another key to the success of mouse cloning is the use of blunt micropipettes attached to a piezo impact-driving micromanipulation device. This system saves a significant amount of time during the micromanipulation of oocytes and thus minimizes the loss of oocyte viability in vitro. For example, a group of 20 oocytes can be enucleated within 10 min by an experienced operator. This protocol is composed of seven parts: (1) preparing micropipettes, (2) setting up the enucleation and injection micropipettes, (3) collecting and enucleating oocytes, (4) preparing nucleus donor cells, (5) injecting donor nuclei, (6) activating embryos and culturing, and (7) transferring cloned embryos. © 2017 Cold Spring Harbor Laboratory Press.

  11. Mice Lacking the Serotonin Htr2B Receptor Gene Present an Antipsychotic-Sensitive Schizophrenic-Like Phenotype

    PubMed Central

    Pitychoutis, Pothitos M; Belmer, Arnauld; Moutkine, Imane; Adrien, Joëlle; Maroteaux, Luc

    2015-01-01

    Impulsivity and hyperactivity share common ground with numerous mental disorders, including schizophrenia. Recently, a population-specific serotonin 2B (5-HT2B) receptor stop codon (ie, HTR2B Q20*) was reported to segregate with severely impulsive individuals, whereas 5-HT2B mutant (Htr2B−/−) mice also showed high impulsivity. Interestingly, in the same cohort, early-onset schizophrenia was more prevalent in HTR2B Q*20 carriers. However, the putative role of 5-HT2B receptor in the neurobiology of schizophrenia has never been investigated. We assessed the effects of the genetic and the pharmacological ablation of 5-HT2B receptors in mice subjected to a comprehensive series of behavioral test screenings for schizophrenic-like symptoms and investigated relevant dopaminergic and glutamatergic neurochemical alterations in the cortex and the striatum. Domains related to the positive, negative, and cognitive symptom clusters of schizophrenia were affected in Htr2B−/− mice, as shown by deficits in sensorimotor gating, in selective attention, in social interactions, and in learning and memory processes. In addition, Htr2B−/− mice presented with enhanced locomotor response to the psychostimulants dizocilpine and amphetamine, and with robust alterations in sleep architecture. Moreover, ablation of 5-HT2B receptors induced a region-selective decrease of dopamine and glutamate concentrations in the dorsal striatum. Importantly, selected schizophrenic-like phenotypes and endophenotypes were rescued by chronic haloperidol treatment. We report herein that 5-HT2B receptor deficiency confers a wide spectrum of antipsychotic-sensitive schizophrenic-like behavioral and psychopharmacological phenotypes in mice and provide first evidence for a role of 5-HT2B receptors in the neurobiology of psychotic disorders. PMID:25936642

  12. Dietary Vitamin D3 suppresses pulmonary immunopathology associated with late stage tuberculosis in C3HeB/FeJ mice

    PubMed Central

    Reeme, Allison E.; Robinson, Richard T.

    2015-01-01

    Tuberculosis (TB) is a significant human disease caused by inhalation of Mycobacterium tuberculosis (Mtb). Left untreated, TB mortality is associated with a failure to resolve pulmonary immunopathology. There is currently widespread interest in using Vitamin D3 (VitD3) as an adjunct therapy for TB, as numerous in vitro studies have shown that VitD3 has direct and indirect mycobactericidal activities. However, to date there have been no in vivo studies addressing whether VitD3 affects experimental TB outcome. Here we use C3HeB/FeJ mice to determine if dietary VitD3 influences the outcome of experimental TB. We observed that although Mtb burdens did not differ between mice on a VitD3-replete diet (VitDHI mice) and mice on a VitD3-deficient diet (VitDLO mice), the inflammatory response in VitDHI mice was significantly attenuated relative to VitDLO controls. Specifically, the expression of multiple inflammatory pathways was reduced in the lungs at later disease stages, as were splenocyte IL12/23p40- and IFNγ-levels following ex vivo restimulation. Dietary VitD3 also suppressed the accumulation of T cells in the mediastinal lymph nodes and lung granulomatous regions, while concomitantly accelerating the accumulation of F4/80+ and Ly6C/Ly6G+ lineages. The altered inflammatory profile of VitDHI mice also associated with reductions in pulmonary immunopathology. VitD receptor deficient (vdr−/−) radiation bone marrow chimeras demonstrate that reductions in pulmonary TB-immunopathology are dependent on hematopoietic VitD-responsiveness. Collectively, our data support a model wherein the in vivo role of VitD3 during TB is not to promote Mtb killing, but rather to function through hematopoietic cells to reduce Mtb-elicited immunopathology. PMID:26729807

  13. Weight-loss changes PPAR expression, reduces atherosclerosis and improves cardiovascular function in obese insulin-resistant mice

    SciTech Connect

    Verreth, Wim; Verhamme, Peter; Pelat, Michael

    2003-09-01

    Weight-loss in obese insulin-resistant, but not in insulin-sensitive, persons reduces CHD risk. It is not known to what extent changes in the adipose gene expression profile are important for reducing CHD risk. We studied the effect of diet restriction-induced weight-loss on gene expression in adipose tissue, atherosclerosis and cardiovascular function in mice with combined leptin and LDL-receptor deficiency. Obesity, hypertriglyceridemia and insulin-resistance are associated with hypertension, impaired left ventricle function and accelerated atherosclerosis in those mice. Diet restriction during 12 weeks caused a 45% weight-loss and changes in the gene expression in adipose tissue of PPARa and PPAR? and ofmore » key genes regulating glucose transport and insulin sensitivity, lipid metabolism, oxidative stress and inflammation, most of which are under the transcriptional control of PPARs. These changes were associated with increased insulin-sensitivity, decreased hypertriglyceridemia, reduced mean 24-hour blood pressure and heart rate, restored circadian variations of blood pressure and heart rate, increased ejection fraction, and reduced atherosclerosis. Thus, induction of PPARa and PPAR? in adipose tissue is a key mechanism for reducing atherosclerosis and improving cardiovascular function resulting from weight-loss. Our observations point to the critical role of PPARs in the pathogenesis of cardiovascular features of the metabolic syndrome.« less

  14. Vasopressin promotes cardiomyocyte hypertrophy via the vasopressin V1A receptor in neonatal mice.

    PubMed

    Hiroyama, Masami; Wang, Shuyi; Aoyagi, Toshinori; Oikawa, Ryo; Sanbe, Atsushi; Takeo, Satoshi; Tanoue, Akito

    2007-03-22

    [Arg8]-vasopressin (AVP) is an essential hormone for maintaining osmotic homeostasis and is known to be a potent vasoconstrictor that regulates the cardiovascular system. In the present study, cardiomyocytes were isolated from neonatal mice and used to investigate the effects of AVP on cardiac hypertrophy. Reverse transcription polymerase chain reaction (RT-PCR) analysis revealed that vasopressin V1A receptor mRNA, but not V1B or V2 receptor mRNA, was expressed in primary cultured neonatal mouse cardiomyocytes. By exposing the cultured neonatal cardiomyocytes to AVP for 24 h, cell surface areas were significantly increased, suggesting that AVP could induce cardiomyocyte growth. We then investigated the expression level of the atrial natriuretic peptide (ANP), which is a marker of cardiac hypertrophy. Stimulation with AVP increased the expression of cardiomyocyte ANP mRNA in a dose- and time-dependent manner. Immunocytochemical studies showed that stimulation with AVP significantly increased the expression of the ANP protein as well. Furthermore, AVP administration activated extracellular signal-regulated kinase (ERK)1/2 in cardiomyocytes. The effects of AVP on these parameters were significantly inhibited by a selective vasopressin V1A receptor antagonist, OPC-21268, and were not observed in cardiomyocytes from mice lacking the vasopressin V1A receptor. In vivo cardiac hypertrophy in response to pressure overload was attenuated in vasopressin V1A receptor-deficient (V1AR-KO) mice. Taken together, our data suggest that AVP promotes cardiomyocyte hypertrophy via the vasopressin V1A receptor, which is in part regulated by the pathway of ERK1/2 signaling.

  15. Roles played by histamine in strenuous or prolonged masseter muscle activity in mice.

    PubMed

    Yoneda, Hiroyuki; Niijima-Yaoita, Fukie; Tsuchiya, Masahiro; Kumamoto, Hiroyuki; Watanbe, Makoto; Ohtsu, Hiroshi; Yanai, Kazuhiko; Tadano, Takeshi; Sasaki, Keiichi; Sugawara, Shunji; Endo, Yasuo

    2013-12-01

    Bruxism and/or clenching, resulting in fatigue or dysfunction of masseter muscles (MM), may cause temporomandibular disorders. Functional support of the microcirculation is critical for prolonged muscle activity. Histamine is a regulator of the microcirculation and is supplied by release from its stores and/or by de novo production via the induction of histidine decarboxylase (HDC). Interleukin (IL)-1, a cytokine involved in temporomandibular disorders, is an inducer of HDC. In the present study, we examined the roles of histamine, HDC and IL-1 in MM activity. Experiments were conducted using our R+G+ model. A mouse restrained (R+) inside a narrow cylinder (front end blocked with a thin plastic strip) gnaws away (G+) the strip to escape, with the weight reduction in the strip serving as an index of MM activity. Fexofenadine (a peripherally acting histamine H1 receptor antagonist) reduced MM activity in normal mice. Both H1 receptor-deficient and HDC-deficient mice exhibited low MM activity. Prolonged R+G+ induced HDC activity in MM. Mast cell-deficient mice exhibited strikingly low HDC induction in MM (and also in the quadriceps femoris muscle) in response to muscle activity or IL-1β. Mast cells were present around blood vessels and nerves in the epimysium and perimysium of MM. These results, together with others reported previously, suggest that: (i) peripheral histamine supports strenuous MM activity; (ii) strenuous MM activity stimulates mast cells to release histamine and to induce HDC (which replenishes the histamine pool in mast cells, possibly mediated by IL-1); and (iii) peripheral histamine H1 receptor antagonists may be effective in treating temporomandibular disorders or preventing prolonged clenching and/or bruxism. © 2013 Wiley Publishing Asia Pty Ltd.

  16. Analgesic Effects of 1st Generation Anti-histamines in Mice.

    PubMed

    Takahashi, Mebae; Shima, Kazuhiro; Tsuchiya, Masahiro; Hagiwara, Yoshihiro; Mizoguchi, Hirokazu; Sakurada, Shinobu; Sugawara, Shunji; Fujita, Takuo; Tadano, Takeshi; Watanabe, Makoto; Fukumoto, Satoshi; Endo, Yasuo

    2016-01-01

    Pain is sensed, transmitted, and modified by a variety of mediators and receptors. Histamine is a well-known mediator of pain. In addition to their anti-histaminic effects, the classical, or 1st generation, anti-histamines (1st AHs) possess, to various degrees, anti-muscarinic, anti-serotonergic, anti-adrenergic, and other pharmacologic effects. Although there have been attempts to use 1st AHs as analgesics and/or analgesic adjuvants, the advent of non-steroidal anti-inflammatory drugs (NSAIDs) discouraged such trials. We previously reported that in patients with temporomandibular disorders, osteoporosis, and/or osteoarthritis, the analgesic effects of certain 1st AHs (chlorpheniramine and diphenhydramine) are superior to those of the NSAIDs flurbiprofen and indomethacin. Here, we compared analgesic effects among 1st AHs and NSAIDs against responses shown by mice to intraperitoneally injected 0.7% acetic acid. Since 1st AHs are water soluble, we selected water-soluble NSAIDs. For direct comparison, drugs were intravenously injected 30 min before the above tests. Histamine-H1-receptor-deficient (H1R-KO) mice were used for evaluating H1-receptor-independent effects. The tested 1st AHs (especially cyproheptadine) displayed or tended to display analgesic effects comparable to those of NSAIDs in normal and H1R-KO mice. Our data suggest that the anti-serotonergic and/or anti-adrenergic effects of 1st AHs make important contributions to their analgesic effects. Moreover, combination of a 1st AH with an NSAID (cyclooxygenase-1 inhibitor) produced remarkably potent analgesic effects. We propose that a 1st AH, by itself or in combination with a cyclooxygenase-1 inhibitor, should undergo testing to evaluate its usefulness in analgesia.

  17. Zika Virus Infection in Dexamethasone-immunosuppressed Mice Demonstrating Disseminated Infection with Multi-organ Involvement Including Orchitis Effectively Treated by Recombinant Type I Interferons.

    PubMed

    Chan, Jasper Fuk-Woo; Zhang, Anna Jinxia; Chan, Chris Chung-Sing; Yip, Cyril Chik-Yan; Mak, Winger Wing-Nga; Zhu, Houshun; Poon, Vincent Kwok-Man; Tee, Kah-Meng; Zhu, Zheng; Cai, Jian-Piao; Tsang, Jessica Oi-Ling; Chik, Kenn Ka-Heng; Yin, Feifei; Chan, Kwok-Hung; Kok, Kin-Hang; Jin, Dong-Yan; Au-Yeung, Rex Kwok-Him; Yuen, Kwok-Yung

    2016-12-01

    Disseminated or fatal Zika virus (ZIKV) infections were reported in immunosuppressed patients. Existing interferon-signaling/receptor-deficient mouse models may not be suitable for evaluating treatment effects of recombinant interferons. We developed a novel mouse model for ZIKV infection by immunosuppressing BALB/c mice with dexamethasone. Dexamethasone-immunosuppressed male mice (6-8weeks) developed disseminated infection as evidenced by the detection of ZIKV-NS1 protein expression and high viral loads in multiple organs. They had ≥10% weight loss and high clinical scores soon after dexamethasone withdrawal (10dpi), which warranted euthanasia at 12dpi. Viral loads in blood and most tissues at 5dpi were significantly higher than those at 12dpi (P<0.05). Histological examination revealed prominent inflammatory infiltrates in multiple organs, and CD45+ and CD8+ inflammatory cells were seen in the testis. These findings suggested that clinical deterioration occurred during viral clearance by host immune response. Type I interferon treatments improved clinical outcome of mice (100% vs 0% survival). Besides virus dissemination, inflammation of various tissues, especially orchitis, may be potential complications of ZIKV infection with significant implications on disease transmission and male fertility. Interferon treatment should be considered in patients at high risks for ZIKV-associated complications when the potential benefits outweigh the side effects of treatment. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Atypical disease after Bordetella pertussis respiratory infection of mice with targeted disruptions of interferon-gamma receptor or immunoglobulin mu chain genes.

    PubMed

    Mahon, B P; Sheahan, B J; Griffin, F; Murphy, G; Mills, K H

    1997-12-01

    Using a murine respiratory challenge model we have previously demonstrated a role for Th1 cells in natural immunity against Bordetella pertussis, but could not rule out a role for antibody. Here we have demonstrated that B. pertussis respiratory infection of mice with targeted disruptions of the genes for the IFN-gamma receptor resulted in an atypical disseminated disease which was lethal in a proportion of animals, and was characterized by pyogranulomatous inflammation and postnecrotic scarring in the livers, mesenteric lymph nodes and kidneys. Viable virulent bacteria were detected in the blood and livers of diseased animals. An examination of the course of infection in the lung of IFN-gamma receptor-deficient, IL-4-deficient and wild-type mice demonstrated that lack of functional IFN-gamma or IL-4, cytokines that are considered to play major roles in regulating the development of Th1 and Th2 cells, respectively, did not affect the kinetics of bacterial elimination from the lung. In contrast, B cell-deficient mice developed a persistent infection and failed to clear the bacteria after aerosol inoculation. These findings demonstrate an absolute requirement for B cells or their products in the resolution of a primary infection with B. pertussis, but also define a critical role for IFN-gamma in containing bacteria to the mucosal site of infection.

  19. Islet Hypersensitivity to Glucose Is Associated With Disrupted Oscillations and Increased Impact of Proinflammatory Cytokines in Islets From Diabetes-Prone Male Mice

    PubMed Central

    Corbin, Kathryn L.; Waters, Christopher D.; Shaffer, Brett K.; Verrilli, Gretchen M.

    2016-01-01

    Pulsatile insulin release is the primary means of blood glucose regulation. The loss of pulsatility is thought to be an early marker and possible factor in developing type 2 diabetes. Another early adaptation in islet function to compensate for obesity is increased glucose sensitivity (left shift) associated with increased basal insulin release. We provide evidence that oscillatory disruptions may be linked with overcompensation (glucose hypersensitivity) in islets from diabetes-prone mice. We isolated islets from male 4- to 5-week-old (prediabetic) and 10- to 12-week-old (diabetic) leptin-receptor-deficient (db/db) mice and age-matched heterozygous controls. After an overnight incubation in media with 11 mM glucose, we measured islet intracellular calcium in 5, 8, 11, or 15 mM glucose. Islets from heterozygous 10- to 12-week-old mice were quiescent in 5 mM glucose and displayed oscillations with increasing amplitude and/or duration in 8, 11, and 15 mM glucose, respectively. Islets from diabetic 10- to 12-week-old mice, in contrast, showed robust oscillations in 5 mM glucose that declined with increasing glucose. Similar trends were observed at 4–5-weeks of age. A progressive left shift in maximal insulin release was also observed in islets as db/db mice aged. Reducing glucokinase activity with 1 mM D-mannoheptulose restored oscillations in 11 mM glucose. Finally, overnight low-dose cytokine exposure negatively impacted oscillations preferentially in high glucose in diabetic islets compared with heterozygous controls. Our findings suggest the following: 1) islets from frankly diabetic mice can produce oscillations, 2) elevated sensitivity to glucose prevents diabetic mouse islets from producing oscillations in normal postprandial (11–15 mM glucose) conditions, and 3) hypersensitivity to glucose may magnify stress effects from inflammation or other sources. PMID:26943366

  20. Islet Hypersensitivity to Glucose Is Associated With Disrupted Oscillations and Increased Impact of Proinflammatory Cytokines in Islets From Diabetes-Prone Male Mice.

    PubMed

    Corbin, Kathryn L; Waters, Christopher D; Shaffer, Brett K; Verrilli, Gretchen M; Nunemaker, Craig S

    2016-05-01

    Pulsatile insulin release is the primary means of blood glucose regulation. The loss of pulsatility is thought to be an early marker and possible factor in developing type 2 diabetes. Another early adaptation in islet function to compensate for obesity is increased glucose sensitivity (left shift) associated with increased basal insulin release. We provide evidence that oscillatory disruptions may be linked with overcompensation (glucose hypersensitivity) in islets from diabetes-prone mice. We isolated islets from male 4- to 5-week-old (prediabetic) and 10- to 12-week-old (diabetic) leptin-receptor-deficient (db/db) mice and age-matched heterozygous controls. After an overnight incubation in media with 11 mM glucose, we measured islet intracellular calcium in 5, 8, 11, or 15 mM glucose. Islets from heterozygous 10- to 12-week-old mice were quiescent in 5 mM glucose and displayed oscillations with increasing amplitude and/or duration in 8, 11, and 15 mM glucose, respectively. Islets from diabetic 10- to 12-week-old mice, in contrast, showed robust oscillations in 5 mM glucose that declined with increasing glucose. Similar trends were observed at 4-5-weeks of age. A progressive left shift in maximal insulin release was also observed in islets as db/db mice aged. Reducing glucokinase activity with 1 mM D-mannoheptulose restored oscillations in 11 mM glucose. Finally, overnight low-dose cytokine exposure negatively impacted oscillations preferentially in high glucose in diabetic islets compared with heterozygous controls. Our findings suggest the following: 1) islets from frankly diabetic mice can produce oscillations, 2) elevated sensitivity to glucose prevents diabetic mouse islets from producing oscillations in normal postprandial (11-15 mM glucose) conditions, and 3) hypersensitivity to glucose may magnify stress effects from inflammation or other sources.

  1. The Addition of Liquid Fructose to a Western-Type Diet in LDL-R-/-Mice Induces Liver Inflammation and Fibrogenesis Markers without Disrupting Insulin Receptor Signalling after an Insulin Challenge.

    PubMed

    Sangüesa, Gemma; Baena, Miguel; Hutter, Natalia; Montañés, José Carlos; Sánchez, Rosa María; Roglans, Núria; Laguna, Juan Carlos; Alegret, Marta

    2017-03-15

    A high consumption of fat and simple sugars, especially fructose, has been related to the development of insulin resistance, but the mechanisms involved in the effects of these nutrients are not fully understood. This study investigates the effects of a Western-type diet and liquid fructose supplementation, alone and combined, on insulin signalling and inflammation in low-density lipoprotein (LDL) receptor-deficient mice (LDL-R -/- ). LDL-R -/- mice were fed chow or Western diet ±15% fructose solution for 12 weeks. Plasma glucose and insulin, and the expression of genes related to inflammation in the liver and visceral white adipose tissue (vWAT), were analysed. V-akt murine thymoma viral oncogene homolog-2 (Akt) activation was measured in the liver of the mice after a single injection of saline or insulin. None of the dietary interventions caused inflammation in vWAT, whereas the Western diet induced hepatic inflammation, which was further enhanced by liquid fructose, leading also to a significant increase in fibrogenesis markers. However, there was no change in plasma glucose or insulin, or insulin-induced Akt phosphorylation. In conclusion, hepatic inflammation and fibrogenesis markers induced by a Western diet supplemented with liquid fructose in LDL-R -/- mice are not associated with a significant impairment of hepatic insulin signalling.

  2. Glucagon-like peptide-1 receptor signalling reduces microvascular thrombosis, nitro-oxidative stress and platelet activation in endotoxaemic mice.

    PubMed

    Steven, Sebastian; Jurk, Kerstin; Kopp, Maximilian; Kröller-Schön, Swenja; Mikhed, Yuliya; Schwierczek, Kathrin; Roohani, Siyer; Kashani, Fatemeh; Oelze, Matthias; Klein, Thomas; Tokalov, Sergey; Danckwardt, Sven; Strand, Susanne; Wenzel, Philip; Münzel, Thomas; Daiber, Andreas

    2017-06-01

    Excessive inflammation in sepsis causes microvascular thrombosis and thrombocytopenia associated with organ dysfunction and high mortality. The present studies aimed to investigate whether inhibition of dipeptidyl peptidase-4 (DPP-4) and supplementation with glucagon-like peptide-1 (GLP-1) receptor agonists improved endotoxaemia-associated microvascular thrombosis via immunomodulatory effects. Endotoxaemia was induced in C57BL/6J mice by a single injection of LPS (17.5 mg kg -1 for survival and 10 mg kg -1 for all other studies). For survival studies, treatment was started 6 h after LPS injection. For all other studies, drugs were injected 48 h before LPS treatment. Mice treated with LPS alone showed severe thrombocytopenia, microvascular thrombosis in the pulmonary circulation (fluorescence imaging), increased LDH activity, endothelial dysfunction and increased markers of inflammation in aorta and whole blood (leukocyte-dependent oxidative burst, nitrosyl-iron haemoglobin, a marker of nitrosative stress, and expression of inducible NOS). Treatment with the DPP-4 inhibitor linagliptin or the GLP-1 receptor agonist liraglutide, as well as genetic deletion of DPP-4 (DPP4 -/- mice) improved all these parameters. In GLP-1 receptor-deficient mice, both linagliptin and liraglutide lost their beneficial effects and improvement of prognosis. Incubation of platelets and cultured monocytes (containing GLP-1 receptor protein) with GLP-1 receptor agonists inhibited the monocytic oxidative burst and platelet activation, with a GLP-1 receptor-dependent elevation of cAMP levels and PKA activation. GLP-1 receptor activation in platelets by linagliptin and liraglutide strongly attenuated endotoxaemia-induced microvascular thrombosis and mortality by a cAMP/PKA-dependent mechanism, preventing systemic inflammation, vascular dysfunction and end organ damage. This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other

  3. Kefir improves fatty liver syndrome by inhibiting the lipogenesis pathway in leptin-deficient ob/ob knockout mice.

    PubMed

    Chen, H-L; Tung, Y-T; Tsai, C-L; Lai, C-W; Lai, Z-L; Tsai, H-C; Lin, Y-L; Wang, C-H; Chen, C-M

    2014-09-01

    Fatty liver disease is commonly associated with obesity, insulin resistance and diabetes. Severe fatty liver is sometimes accompanied by steatohepatitis and may lead to the development of hepatocellular carcinoma. At present, there is no effective treatment for non-alcoholic fatty liver disease (NAFLD); thus, recent investigations have focused on developing effective therapeutics to treat this condition. This study aimed to evaluate the effects of kefir on the hepatic lipid metabolism of ob/ob mice, which are commonly used to model fatty liver disease. In this study, we used leptin receptor-deficient ob/ob mice as an animal disease model of NAFLD. Six-week-old ob/ob mice were orally administered the dairy product kefir (140 mg kg(-1) of body weight (BW) per day) for 4 weeks. The data demonstrated that kefir improved fatty liver syndrome on BW, energy expenditure and basal metabolic rate by inhibiting serum glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities (P<0.05) and by decreasing the triglyceride (TG) and total cholesterol (TC) contents of the liver (P<0.05). Oral kefir administration also significantly reduced the macrovesicular fat quantity in liver tissue. In addition, kefir markedly decreased the expression of the genes sterol regulatory element-binding protein 1 (SREBP1), fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) (P<0.05) but not the expression of peroxisome proliferator-activated receptor α (PPARα) or hepatic carnitine palmitoyltransferase-1α (CPT1α) in the livers of ob/ob mice. On the basis of these results, we conclude that kefir improves NAFLD on BW, energy expenditure and basal metabolic rate by inhibiting the lipogenesis pathway and that kefir may have the potential for clinical application to the prevention or treatment of NAFLD.

  4. PAC1- and VPAC2 receptors in light regulated behavior and physiology: Studies in single and double mutant mice

    PubMed Central

    Georg, Birgitte; Fahrenkrug, Jan

    2017-01-01

    The two sister peptides, pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal polypeptide (VIP) and their receptors, the PAC1 –and the VPAC2 receptors, are involved in regulation of the circadian timing system. PACAP as a neurotransmitter in the retinohypothalamic tract (RHT) and VIP as a neurotransmitter, involved in synchronization of SCN neurons. Behavior and physiology in VPAC2 deficient mice are strongly regulated by light most likely as a result of masking. Consequently, we used VPAC2 and PAC1/VPAC2 double mutant mice in comparison with PAC1 receptor deficient mice to further elucidate the role of PACAP in the light mediated regulation of behavior and physiology of the circadian system. We compared circadian rhythms in mice equipped with running wheels or implanted radio-transmitter measuring core body temperature kept in a full photoperiod ((FPP)(12:12 h light dark-cycles (LD)) and skeleton photo periods (SPP) at high and low light intensity. Furthermore, we examined the expression of PAC1- and VPAC2 receptors in the SCN of the different genotypes in combination with visualization of PACAP and VIP and determined whether compensatory changes in peptide and/or receptor expression in the reciprocal knockouts (KO) (PAC1 and VPAC2) had occurred. Our data demonstrate that in although being closely related at both ligand and receptor structure/sequence, PACAP/PAC1 receptor signaling are independent of VIP/VPAC2 receptor signaling and vice versa. Furthermore, lack of either of the receptors does not result in compensatory changes at neither the physiological or anatomical level. PACAP/PAC1 signaling is important for light regulated behavior, VIP/VPAC2signaling for stable clock function and both signaling pathways may play a role in shaping diurnality versus nocturnality. PMID:29155851

  5. Speckle tracking echocardiography in the diagnosis of early left ventricular systolic dysfunction in type II diabetic mice.

    PubMed

    Li, Rong-juan; Yang, Jiao; Yang, Ya; Ma, Ning; Jiang, Bo; Sun, Qi-wei; Li, Yi-jia

    2014-10-08

    The leptin receptor-deficient db/db mouse is a well-established type II diabetes animal model used to investigate diabetic cardiomyopathy. Previous reports have documented diabetic cardiomyopathy is accompanied by cardiac structural and functional abnormalities. To better elucidate early or subtle changes in cardiac performance in db/db mice, we used speckle tracking echocardiography to assess systolic myocardial strain in vivo with diabetic db/db mice in order to study early changes of left ventricle contractile function in type II diabetes model. Male diabetic db/db mice and age-matched control mice from C57BL/6J strain at 8,12 and 16 weeks of age were subjected to echocardiography. At the midpapillary level in the parasternal left ventricular short-axis view, end diastolic and systolic left ventricular diameter, interventricular septal thickness and posterior wall thicknesses, ejection fraction, fractional shortening were determined by M-mode echocardiography. Using speckle-tracking based strain analysis of two-dimensional echocardiographic images acquired from the parasternal short-axis views at the mid-papillary level, systolic global radial and circumferential strain values were analyzed. There was no significant difference in interventricular septal thickness, posterior wall thicknesses, end diastolic and systolic left ventricular diameter, ejection fraction and fractional shortening between db/db and age-matched control mice at 8,12 or 16 weeks of age (P > 0.05). At 8 and 12 weeks of age, there was no significant difference in left ventricular radial strain and circumferential strain between db/db mice and age-matched controls (P > 0.05). But at 16 weeks of age, the left ventricular radial strain and circumferential strain in db/db mice were lower than in control mice (P < 0.01). The present study shows that speckle tracking echocardiography can be used to evaluate cardiac functional alterations in mouse models of cardiovascular disease. Radial and

  6. Growth arrest and DNA damage-inducible 34 regulates liver regeneration in hepatic steatosis in mice.

    PubMed

    Inaba, Yuka; Furutani, Tomoko; Kimura, Kumi; Watanabe, Hitoshi; Haga, Sanae; Kido, Yoshiaki; Matsumoto, Michihiro; Yamamoto, Yasuhiko; Harada, Kenichi; Kaneko, Shuichi; Oyadomari, Seiichi; Ozaki, Michitaka; Kasuga, Masato; Inoue, Hiroshi

    2015-04-01

    The liver has robust regenerative potential in response to damage, but hepatic steatosis (HS) weakens this potential. We found that the enhanced integrated stress response (ISR) mediated by phosphorylation of the alpha subunit of eukaryotic initiation factor 2 (eIF2α) impairs regeneration in HS and that growth arrest and DNA damage-inducible 34 (Gadd34)-dependent suppression of ISR plays a crucial role in fatty liver regeneration. Although mice fed a high-fat diet for 2 weeks developed moderate fatty liver with no increase in eIF2α phosphorylation before 70% hepatectomy, they showed impaired liver regeneration as a result of reduced proliferation and increased death of hepatocytes with increased phosphorylation of eIF2α and ISR. An increased ISR through Gadd34 knockdown induced C/EBP homologous protein (CHOP)-dependent apoptosis and receptor-interacting protein kinase 3-dependent necrosis, resulting in increased hepatocyte death during fatty liver regeneration. Furthermore, Gadd34 knockdown and increased phosphorylation of eIF2α decreased cyclin D1 protein and reduced hepatocyte proliferation. In contrast, enhancement of Gadd34 suppressed phosphorylation of eIF2α and reduced CHOP expression and hepatocyte apoptosis without affecting hepatocyte proliferation, clearly improving fatty liver regeneration. In more severe fatty liver of leptin receptor-deficient db/db mice, forced expression of hepatic Gadd34 also promoted hepatic regeneration after hepatectomy. Gadd34-mediated regulation of ISR acts as a physiological defense mechanism against impaired liver regeneration resulting from steatosis and is thus a possible therapeutic target for impaired regeneration in HS. © 2014 by the American Association for the Study of Liver Diseases.

  7. Nobiletin attenuates VLDL overproduction, dyslipidemia, and atherosclerosis in mice with diet-induced insulin resistance.

    PubMed

    Mulvihill, Erin E; Assini, Julia M; Lee, Justin K; Allister, Emma M; Sutherland, Brian G; Koppes, Julie B; Sawyez, Cynthia G; Edwards, Jane Y; Telford, Dawn E; Charbonneau, Alexandre; St-Pierre, Philippe; Marette, André; Huff, Murray W

    2011-05-01

    Increased plasma concentrations of apolipoprotein B100 often present in patients with insulin resistance and confer increased risk for the development of atherosclerosis. Naturally occurring polyphenolic compounds including flavonoids have antiatherogenic properties. The aim of the current study was to evaluate the effect of the polymethoxylated flavonoid nobiletin on lipoprotein secretion in cultured human hepatoma cells (HepG2) and in a mouse model of insulin resistance and atherosclerosis. Lipoprotein secretion was determined in HepG2 cells incubated with nobiletin or insulin. mRNA abundance was evaluated by quantitative real-time PCR, and Western blotting was used to demonstrate activation of cell signaling pathways. In LDL receptor-deficient mice (Ldlr(-/-)) fed a Western diet supplemented with nobiletin, metabolic parameters, gene expression, fatty acid oxidation, glucose homeostasis, and energy expenditure were documented. Atherosclerosis was quantitated by histological analysis. In HepG2 cells, activation of mitogen-activated protein kinase-extracellular signal-related kinase signaling by nobiletin or insulin increased LDLR and decreased MTP and DGAT1/2 mRNA, resulting in marked inhibition of apoB100 secretion. Nobiletin, unlike insulin, did not induce phosphorylation of the insulin receptor or insulin receptor substrate-1 and did not stimulate lipogenesis. In fat-fed Ldlr(-/-) mice, nobiletin attenuated dyslipidemia through a reduction in VLDL-triglyceride (TG) secretion. Nobiletin prevented hepatic TG accumulation, increased expression of Pgc1α and Cpt1α, and enhanced fatty acid β-oxidation. Nobiletin did not activate any peroxisome proliferator-activated receptor (PPAR), indicating that the metabolic effects were PPAR independent. Nobiletin increased hepatic and peripheral insulin sensitivity and glucose tolerance and dramatically attenuated atherosclerosis in the aortic sinus. Nobiletin provides insight into treatments for dyslipidemia and

  8. In vivo inhibition of nuclear factor of activated T-cells leads to atherosclerotic plaque regression in IGF-II/LDLR-/-ApoB100/100 mice.

    PubMed

    Blanco, Fabiana; Heinonen, Suvi E; Gurzeler, Erika; Berglund, Lisa M; Dutius Andersson, Anna-Maria; Kotova, Olga; Jönsson-Rylander, Ann-Cathrine; Ylä-Herttuala, Seppo; Gomez, Maria F

    2018-03-01

    Despite vast clinical experience linking diabetes and atherosclerosis, the molecular mechanisms leading to accelerated vascular damage are still unclear. Here, we investigated the effects of nuclear factor of activated T-cells inhibition on plaque burden in a novel mouse model of type 2 diabetes that better replicates human disease. IGF-II/LDLR -/- ApoB 100/100 mice were generated by crossbreeding low-density lipoprotein receptor-deficient mice that synthesize only apolipoprotein B100 (LDLR -/- ApoB 100/100 ) with transgenic mice overexpressing insulin-like growth factor-II in pancreatic β cells. Mice have mild hyperglycaemia and hyperinsulinaemia and develop complex atherosclerotic lesions. In vivo treatment with the nuclear factor of activated T-cells blocker A-285222 for 4 weeks reduced atherosclerotic plaque area and degree of stenosis in the brachiocephalic artery of IGF-II/LDLR -/- ApoB 100/100 mice, as assessed non-invasively using ultrasound biomicroscopy prior and after treatment, and histologically after termination. Treatment had no impact on plaque composition (i.e. muscle, collagen, macrophages). The reduced plaque area could not be explained by effects of A-285222 on plasma glucose, insulin or lipids. Inhibition of nuclear factor of activated T-cells was associated with increased expression of atheroprotective NOX4 and of the anti-oxidant enzyme catalase in aortic vascular smooth muscle cells. Targeting the nuclear factor of activated T-cells signalling pathway may be an attractive approach for the treatment of diabetic macrovascular complications.

  9. Adenosine 5'-monophosphate ameliorates D-galactosamine/lipopolysaccharide-induced liver injury through an adenosine receptor-independent mechanism in mice.

    PubMed

    Zhan, Y; Wang, Z; Yang, P; Wang, T; Xia, L; Zhou, M; Wang, Y; Wang, S; Hua, Z; Zhang, J

    2014-01-09

    D-galactosamine (GalN)/lipopolysaccharide (LPS)-induced lethality and acute liver failure is dependent on endogenously produced inflammatory cytokines. Adenosine has been proven to be a central role in the regulation of inflammatory response. It is not entirely clear that which adenosine action is actually crucial to limiting inflammatory tissue destruction. Here we showed that GalN/LPS challenge elevated hepatic adenosine and induced lethality in adenosine receptor-deficient mice with equal efficiency as wild-type mice. In GalN/LPS-treated mice, pretreatment with adenosine 5'-monophosphate (5'-AMP) significantly elevated hepatic adenosine level and reduced mortality through decreasing cytokine and chemokine production. In RAW264.7 cells, 5'-AMP treatment inhibited the production of inflammatory cytokines, which is not mediated through adenosine receptors. 5'-AMP failed to attenuate LPS-induced nuclear factor-κB (NF-κB) p65 nuclear translocation, but reduced LPS-induced recruitment of NF-κB p65 to inflammatory gene promoters and decreased LPS-induced enrichment of H3K4 dimethylation at the tumor necrosis factor-α (TNF-α) promoter, which was involved in 5'-AMP-induced elevation of cellular adenosine and a decline of methylation potential. In vitro biochemical analysis revealed that adenosine directly attenuated recruitment of NF-κB to the TNF-α and interleukin-6 promoters. Our findings demonstrate that 5'-AMP-inhibiting inflammatory response is not mediated by adenosine receptors and it may represent a potential protective agent for amelioration of LPS-induced liver injury.

  10. Biomechanical modeling and morphology analysis indicates plaque rupture due to mechanical failure unlikely in atherosclerosis-prone mice

    PubMed Central

    Campbell, Ian C.; Weiss, Daiana; Suever, Jonathan D.; Virmani, Renu; Veneziani, Alessandro; Vito, Raymond P.; Oshinski, John N.

    2013-01-01

    Spontaneous plaque rupture in mouse models of atherosclerosis is controversial, although numerous studies have discussed so-called “vulnerable plaque” phenotypes in mice. We compared the morphology and biomechanics of two acute and one chronic murine model of atherosclerosis to human coronaries of the thin-cap fibroatheroma (TCFA) phenotype. Our acute models were apolipoprotein E-deficient (ApoE−/−) and LDL receptor-deficient (LDLr−/−) mice, both fed a high-fat diet for 8 wk with simultaneous infusion of angiotensin II (ANG II), and our chronic mouse model was the apolipoprotein E-deficient strain fed a regular chow diet for 1 yr. We found that the mouse plaques from all three models exhibited significant morphological differences from human TCFA plaques, including the plaque burden, plaque thickness, eccentricity, and amount of the vessel wall covered by lesion as well as significant differences in the relative composition of plaques. These morphological differences suggested that the distribution of solid mechanical stresses in the walls may differ as well. Using a finite-element analysis computational solid mechanics model, we computed the relative distribution of stresses in the walls of murine and human plaques and found that although human TCFA plaques have the highest stresses in the thin fibrous cap, murine lesions do not have such stress distributions. Instead, local maxima of stresses were on the media and adventitia, away from the plaque. Our results suggest that if plaque rupture is possible in mice, it may be driven by a different mechanism than mechanics. PMID:23203971

  11. P2Y receptors and atherosclerosis in apolipoprotein E-deficient mice

    PubMed Central

    Guns, Pieter-Jan DF; Hendrickx, Jan; Van Assche, Tim; Fransen, Paul; Bult, Hidde

    2010-01-01

    Background and purpose: P2Y nucleotide receptors are involved in the regulation of vascular tone, smooth muscle cell (SMC) proliferation and inflammatory responses. The present study investigated whether they are involved in atherosclerosis. Experimental approach: mRNA of P2Y receptors was quantified (RT-PCR) in atherosclerotic and plaque-free aorta segments of apolipoprotein E-deficient (apoE–/–) mice. Macrophage activation was assessed in J774 macrophages, and effects of non-selective purinoceptor antagonists on atherosclerosis were evaluated in cholesterol-fed apoE–/– mice. Key results: P2Y6 receptor mRNA was consistently elevated in segments with atherosclerosis, whereas P2Y2 receptor expression remained unchanged. Expression of P2Y1 or P2Y4 receptor mRNA was low or undetectable, and not influenced by atherosclerosis. P2Y6 mRNA expression was higher in cultured J774 macrophages than in cultured aortic SMCs. Furthermore, immunohistochemical staining of plaques demonstrated P2Y6-positive macrophages, but few SMCs, suggesting that macrophage recruitment accounted for the increase in P2Y6 receptor mRNA during atherosclerosis. In contrast to ATP, the P2Y6-selective agonist UDP increased mRNA expression and activity of inducible nitric oxide synthase and interleukin-6 in J774 macrophages; this effect was blocked by suramin (100–300 µM) or pyridoxal-phosphate-6-azophenyl-2′-4′-disulphonic acid (PPADS, 10–30 µM). Finally, 4-week treatment of cholesterol-fed apoE–/– mice with suramin or PPADS (50 and 25 mg·kg−1·day−1 respectively) reduced plaque size, without changing plaque composition (relative SMC and macrophage content) or cell replication. Conclusions and implications: These results suggest involvement of nucleotide receptors, particularly P2Y6 receptors, during atherosclerosis, and warrant further research with selective purinoceptor antagonists or P2Y6 receptor-deficient mice. PMID:20050854

  12. Oral lactoferrin protects against experimental candidiasis in mice.

    PubMed

    Velliyagounder, K; Alsaedi, W; Alabdulmohsen, W; Markowitz, K; Fine, D H

    2015-01-01

    To determine the role of human lactoferrin (hLF) in protecting the oral cavities of mice against Candida albicans infection in lactoferrin knockout (LFKO(-/-)) mice was compared to wild-type (WT) mice. We also aim to determine the protective role of hLF in LFKO(-/-) mice. Antibiotic-treated immunosuppressed mice were inoculated with C. albicans (or sham infection) by oral swab and evaluated for the severity of infection after 7 days of infection. To determine the protective role of hLF, we added 0·3% solution of hLF to the drinking water given to some of the mice. CFU count, scoring of lesions and microscopic observations were carried out to determine the severity of infection. LFKO(-/-) I mice showed a 2 log (P = 0·001) higher CFUs of C. albicans in the oral cavity compared to the WT mice infected with C. albicans (WTI). LFKO(-/-) I mice given hLF had a 3 log (P = 0·001) reduction in CFUs in the oral cavity compared to untreated LFKO(-/-) I mice. The severity of infection, observed by light microscopy, revealed that the tongue of the LFKO(-/-) I mice showed more white patches compared to WTI and LFKO(-/-) I + hLF mice. Scanning electron microscopic observations revealed that more filiform papillae were destroyed in LFKO(-/-) I mice when compared to WTI or LFKO(-/-) I + hLF mice. Human LF is important in protecting mice from oral C. albicans infection. Administered hLF may be used to prevent C. albicans infection. Human LF, a multifunctional iron-binding glycoprotein can be used as a therapeutic active ingredient in oral healthcare products against C. albicans. © 2014 The Society for Applied Microbiology.

  13. Oral lactoferrin protects against experimental candidiasis in mice

    PubMed Central

    Velliyagounder, Kabilan; Alsaedi, Wijdan; Alabdulmohsen, Waad; Markowitz, Kenneth; Fine, Daniel H.

    2015-01-01

    Aims To determine the role of lactoferrin in protecting the oral cavities of mice against Candida albicans infection in lactoferrin knockout (LFKO−/−) mice were compared to wild-type (WT) mice. We also determine the protective role of human lactoferrin in the LFKO−/− mice. Methods and Results Antibiotic treated immunosuppressed mice were inoculated with C. albicans (or sham infection) by oral swab and evaluated for the severity of infection after 7 days of infection. To determine the protective role of hLF, we added 0.3% solution of hLF to the drinking water given to some of the mice. CFU count, scoring of lesions and microscopic observations were carried out to determine the severity of infection. LFKO−/−I mice showed a 2 log (P=0.001) higher CFUs of C. albicans in the oral cavity compared to the WTI mice. LFKO−/−I mice given hLF had a 3 log (P=0.001) reduction in CFUs in the oral cavity compared to untreated LFKO−/−I mice. The severity of infection, observed by light microscopy revealed that the tongue of the LFKO−/−I mice showed more white patches compared to WTI and LFKO−/−I+hLF mice. Scanning electron microscopic observation revealed that more filiform papillae were destroyed in LFKO−/−I mice when compared to WTI or LFKO−/−I +hLF mice. Conclusions Human lactoferrin is important in protecting mice from oral C. albicans infection. Administered hLF may be used to prevent C. albicans infection. Significance and Impact of the Study Human lactoferrin, a multifunctional iron-binding glycoprotein can be used as a therapeutic active ingredient in oral health care products against C. albicans. PMID:25319508

  14. Activation but not blockade of GABAB receptors during early-life alters anxiety in adulthood in BALB/c mice.

    PubMed

    Sweeney, Fabian F; O'Leary, Olivia F; Cryan, John F

    2014-06-01

    Although the underlying pathophysiology of anxiety disorders is unknown it is clear that a combination of genetic and environmental factors in early life predispose to disease risk. Preclinical research increasingly suggests an important role for the GABAB receptor in modulating anxiety behaviour, with GABAB receptor deficient mice having increased anxiety behaviour. Previous studies have highlighted critical windows during development where adult anxiety behaviour is primed. However, little is known regarding the role played by the GABAB receptors in the developmental processes that underlie adult anxiety behaviour. To this end, we treated male BALB/c mouse pups with the either the selective GABAB receptor agonist, R-baclofen (2 mg/kg, s.c), the GABAB receptor antagonist CGP 52432 (10 mg/kg and 30 mg/kg) or vehicle from postnatal days (P) 14-28. The anxiety behaviour of these mice was then assessed in adulthood (P62 onwards) in a battery of behavioural tests comprising; the stress induced hyperthermia (SIH) test, defensive marble burying (DMB), elevated-plus maze (EPM) and the forced swim test (FST). Postnatal R-baclofen treatment resulted in increased anxiety-like behaviour in the EPM as shown by approach-avoidance and ethological measures. Other behavioural measures were not significantly altered. Interestingly, blockade of GABAB receptors with CGP52432 in early life caused no alterations in emotional behaviour. These data suggest that during early life GABAB receptor signalling can play a functional role in programing anxiety behaviour in adulthood. The underlying neurodevelopmental processes underlying these effects remain to be discovered. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Effects of Pediococcus parvulus 2.6 and its exopolysaccharide on plasma cholesterol levels and inflammatory markers in mice

    PubMed Central

    2012-01-01

    Intake of dietary fibres may reduce the prevalence of physiological risk factors of the metabolic syndrome, such as high plasma lipid levels and low-grade inflammatory state. Dietary fibres are usually of plant origin however microbial exopolysaccharides (EPSs) have analogue structures that could potentially exert similar physiological effects. Pediococcus parvulus 2.6 (Pd 2.6) excretes a ropy EPS and has previously shown probiotic potential. The aim of this work was to evaluate physiological effects of Pd 2.6 and its EPS in vivo. The live Pd 2.6 (both the ropy and non-ropy isogenic variant) and its purified EPS were fed to hypercholesterolemic LDL-receptor deficient mice for 6 weeks to investigate their effects on cholesterol levels and the inflammatory tone of the animals. Both variants of Pd 2.6 survived passage through the mouse gut fulfilling an important criterion of probiotics. The ability to produce EPS was conferring an advantage to survival (faecal recovery of 3.7 (1.9-8.7) vs. 0.21 (0.14-0.34) *108 CFU, P < 0.001, median and 25th and 75th percentiles). The ropy Pd 2.6 decreased the levels of soluble vascular cell adhesion molecule-1 compared to the EPS alone (591 ± 14 vs. 646 ± 13 ng/ml, P < 0.05). An increase in liver weight in mice fed the purified EPS was observed, but with no change in liver lipids. No changes in blood lipids were detected in any group. Further the EPS induced growth of the caecal tissue and increased the amount of caecal content showing bulking properties like that of a dietary fibre. PMID:23234432

  16. Generation of transgenic mice.

    PubMed

    Cho, Andrew; Haruyama, Naoto; Kulkarni, Ashok B

    2009-03-01

    This unit describes detailed step-by-step protocols, reagents, and equipment required for successful generation of transgenic mice using pronuclear injection. The experimental methods and practical tips given here will help guide beginners in understanding what is required and what to avoid in these standard protocols for efficiently generating transgenic mice. Copyright 2009 by John Wiley & Sons, Inc.

  17. Generation of Transgenic Mice

    PubMed Central

    Cho, Andrew; Haruyama, Naoto; Kulkarni, Ashok B.

    2009-01-01

    This unit describes detailed step-by-step protocols, reagents, and equipment required for successful generation of transgenic mice using pronuclear injection. The experimental methods and practical tips given here will help guide beginners in understanding what is required and what to avoid in these standard protocols for efficiently generating transgenic mice. PMID:19283729

  18. Chronic Co-species Housing Mice and Rats Increased the Competitiveness of Male Mice.

    PubMed

    Liu, Ying-Juan; Li, Lai-Fu; Zhang, Yao-Hua; Guo, Hui-Fen; Xia, Min; Zhang, Meng-Wei; Jing, Xiao-Yuan; Zhang, Jing-Hua; Zhang, Jian-Xu

    2017-03-01

    Rats are predators of mice in nature. Nevertheless, it is a common practice to house mice and rats in a same room in some laboratories. In this study, we investigated the behavioral and physiological responsively of mice in long-term co-species housing conditions. Twenty-four male mice were randomly assigned to their original raising room (control) or a rat room (co-species-housed) for more than 6 weeks. In the open-field and light-dark box tests, the behaviors of the co-species-housed mice and controls were not different. In a 2-choice test of paired urine odors [rabbit urine (as a novel odor) vs. rat urine, cat urine (as a natural predator-scent) vs. rabbit urine, and cat urine vs. rat urine], the co-species-housed mice were more ready to investigate the rat urine odor compared with the controls and may have adapted to it. In an encounter test, the rat-room-exposed mice exhibited increased aggression levels, and their urines were more attractive to females. Correspondingly, the levels of major urinary proteins were increased in the co-species-housed mouse urine, along with some volatile pheromones. The serum testosterone levels were also enhanced in the co-species-housed mice, whereas the corticosterone levels were not different. The norepinephrine, dopamine, and 5-HT levels in the right hippocampus and striatum were not different between the 2. Our findings indicate that chronic co-species housing results in adaptation in male mice; furthermore, it appears that long-term rat-odor stimuli enhance the competitiveness of mice, which suggests that appropriate predator-odor stimuli may be important to the fitness of prey animals. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Adenosine 5′-monophosphate ameliorates D-galactosamine/lipopolysaccharide-induced liver injury through an adenosine receptor-independent mechanism in mice

    PubMed Central

    Zhan, Y; Wang, Z; Yang, P; Wang, T; Xia, L; Zhou, M; Wang, Y; Wang, S; Hua, Z; Zhang, J

    2014-01-01

    D-galactosamine (GalN)/lipopolysaccharide (LPS)-induced lethality and acute liver failure is dependent on endogenously produced inflammatory cytokines. Adenosine has been proven to be a central role in the regulation of inflammatory response. It is not entirely clear that which adenosine action is actually crucial to limiting inflammatory tissue destruction. Here we showed that GalN/LPS challenge elevated hepatic adenosine and induced lethality in adenosine receptor-deficient mice with equal efficiency as wild-type mice. In GalN/LPS-treated mice, pretreatment with adenosine 5′-monophosphate (5′-AMP) significantly elevated hepatic adenosine level and reduced mortality through decreasing cytokine and chemokine production. In RAW264.7 cells, 5′-AMP treatment inhibited the production of inflammatory cytokines, which is not mediated through adenosine receptors. 5′-AMP failed to attenuate LPS-induced nuclear factor-κB (NF-κB) p65 nuclear translocation, but reduced LPS-induced recruitment of NF-κB p65 to inflammatory gene promoters and decreased LPS-induced enrichment of H3K4 dimethylation at the tumor necrosis factor-α (TNF-α) promoter, which was involved in 5′-AMP-induced elevation of cellular adenosine and a decline of methylation potential. In vitro biochemical analysis revealed that adenosine directly attenuated recruitment of NF-κB to the TNF-α and interleukin-6 promoters. Our findings demonstrate that 5′-AMP-inhibiting inflammatory response is not mediated by adenosine receptors and it may represent a potential protective agent for amelioration of LPS-induced liver injury. PMID:24407238

  20. HtrA2/Omi, a sheep in wolf's clothing.

    PubMed

    Vaux, David L; Silke, John

    2003-10-31

    Mammalian mitochondrial HtrA2/Omi was originally described as an apoptosis inducer, but rather than having extra cells, mice with mutant HtrA2/Omi suffer from a neurodegenerative disease due to progressive mitochondrial damage. This suggests that instead of promoting cell death by antagonizing inhibitor of apoptosis (IAP) proteins, the primary function of HtrA2/Omi is to handle misfolded proteins in the mitochondria.

  1. A Single Mutation in the VP1 of Enterovirus 71 Is Responsible for Increased Virulence and Neurotropism in Adult Interferon-Deficient Mice.

    PubMed

    Caine, Elizabeth A; Moncla, Louise H; Ronderos, Monica D; Friedrich, Thomas C; Osorio, Jorge E

    2016-10-01

    Hand, foot, and mouth disease (HFMD) has spread throughout the Asia-Pacific region, affecting millions of young children, who develop symptoms ranging from painful blisters around their mouths and hands to neurological complications. Many members of the genus Enterovirus (family Picornaviridae) cause HFMD. Enterovirus 71 (EV71) is one of the primary causative agents and has been linked to severe disease. Vaccine efficacy and pathogenesis studies for EV71 have been limited because there is a lack of suitable animal models. Previously, we generated a mouse-adapted EV71 (mEV71) capable of infecting 12-week-old interferon receptor-deficient AG129 mice and used the model to evaluate the efficacy of candidate HFMD vaccines. Here, we present data investigating the genetic correlates of EV71 adaptation and characterize the virus's tissue tropism in mice. Using reverse genetics, a VP1 mutation (K244E) was shown to be necessary for mEV71 virulence in adult mice. Another VP1 mutation (H37R) was required for mEV71 recovery on rhabdomyosarcoma (RD) cells. Viral loads determined by real-time reverse transcription (RT)-PCR confirmed the presence of mEV71 in the sera and multiple organs of mice. Histological analysis revealed signs of meningitis and encephalitis, characteristic of severe human disease. The further description of this model has provided insight into EV71 pathogenesis and demonstrates the importance of the VP1 region in facilitating mEV71 adaptation. EV71 is a reemerging pathogen, and little is known about the genetic determinants involved in its pathogenesis. The absence of animal models has contributed to this lack of knowledge. The data presented here improve upon the existing animal models by characterizing a mouse-adapted strain of EV71. We determined that a VP1 mutation (K244E) was needed for EV71 virulence in adult AG129 mice. While this mutation was found previously for EV71 adaptation in 5-day-old BALB/c mice, neurotropic disease did not develop. Using

  2. Effects of Gametophytes of Ecklonia Kurome on the Levels of Glucose and Triacylglycerol in db/db, Prediabetic C57BL/6J and IFN-γ KO Mice

    PubMed Central

    Dwiranti, Febriza; Hiraoka, Masanori; Taguchi, Takahiro; Konishi, Yuko; Tominaga, Mari; Tominaga, Akira

    2012-01-01

    We have studied edible algae that have the potential to down-regulate blood glucose. In Japan, Ecklonia species have been believed to improve the circulation of blood. In this study, we used leptin receptor deficient type 2 diabetes model mice (db/db) and prediabetic C57BL/6J mice. We also focused on the role of IFN-γ in the control of blood levels of triacylglycerol and glucose, because it is reportedly engaged in the regulation of energy consumption together with leptin. We report that gametophytes of Ecklonia kurome down-regulate the blood level of glucose and serum level of triacylglycerol in db/db. We also report that gametophytes of Ecklonia kurome down-regulate the level of glucose but not the level of triacylglycerol in prediabetic C57BL/6J mice induced by a high fat diet. They increased the level of triacylglycerol compared to that of control group in C57BL/6J, but not in IFN-γ KO mice. Gametophytes of Ecklonia kurome were administered orally to prediabetic C57BL/6J and IFN-γ KO mice and oral glucose tolerance tests were performed to evaluate the effects of algae. During the administration of the normal diet, we found a higher level of blood glucose in a glucose tolerance test of IFN-γ KO mice compared with that of C57BL/6J. Although a high fat diet induced a higher level of blood glucose compared with a normal diet group in a glucose tolerance test of C57BL/6J mice, this effect of high fat diet was not observed clearly at first but appeared three hours after glucose administration in IFN-γ KO mice. Gametophytes of Ecklonia kurome down-regulated the level of blood glucose in both C57BL/6J and IFN-γ KO mice, when administered a normal diet after making them prediabetic. These results suggest that Ecklonia kurome are effective to down-regulate the blood glucose and IFN-γ is involved in the regulation of blood glucose and triacylglycerol. PMID:23675258

  3. Dwarf Mice and Aging.

    PubMed

    Masternak, Michal M; Darcy, Justin; Victoria, Berta; Bartke, Andrzej

    2018-01-01

    Dwarf mice have been studied for many decades, however, the focus of these studies shifted in 1996 when it was shown by Brown-Borg and her coworkers that Ames dwarf (Prop1 df ) mice are exceptionally long-lived. Since then, Snell dwarf (Pit1 dw ) and growth hormone receptor knockout (GHR-KO, a.k.a. Laron dwarf) mice were also shown to be exceptionally long-lived, presumably due to their growth hormone (GH)-deficiency or -resistance, respectively. What is of equal importance in these dwarf mice is their extended health span, that is, these animals have a longer period of life lived free of frailty and age-related diseases. This review article focuses on recent studies conducted in these dwarf mice, which concerned brown and white adipose tissue biology, microRNA (miRNA) profiling, as well as early-life dietary and hormonal interventions. Results of these studies identify novel mechanisms linking reduced GH action with extensions of both life span and health span. Copyright © 2017. Published by Elsevier Inc.

  4. The apolipoprotein-AI mimetic peptide L4F at a modest dose does not attenuate weight gain, inflammation, or atherosclerosis in LDLR-null mice.

    PubMed

    Averill, Michelle M; Kim, Eung Ju; Goodspeed, Leela; Wang, Shari; Subramanian, Savitha; Den Hartigh, Laura J; Tang, Chongren; Ding, Yilei; Reardon, Catherine A; Getz, Godfrey S; Chait, Alan

    2014-01-01

    High density lipoprotein (HDL) cholesterol levels are inversely related to cardiovascular disease risk and associated with a reduced risk of type 2 diabetes. Apolipoprotein A-I (apoA-I; major HDL protein) mimetics have been reported to reduce atherosclerosis and decrease adiposity. This study investigated the effect of L4F mimetic peptide and apoA-I overexpression on weight gain, insulin resistance, and atherosclerosis in an LDL receptor deficient (Ldlr-/-) model fed a high fat high sucrose with cholesterol (HFHSC) diet. Studies in differentiated 3T3-L1 adipocytes tested whether L4F could inhibit palmitate-induced adipocyte inflammation. In vivo studies used male Ldlr-/- mice fed a HFHSC diet for 12 weeks and were injected daily with L4F (100 µg/mouse) subcutaneously during the last 8 weeks. Wild-type and apoA-I overexpressing Ldlr-/- mice were fed HFHSC diet for 16 weeks. Neither L4F administration nor apoA-I overexpression affected weight gain, total plasma cholesterol or triglycerides in our studies. While pre-treatment of 3T3-L1 adipocytes with either L4F or HDL abolished palmitate-induced cytokine expression in vitro, L4F treatment did not affect circulating or adipose tissue inflammatory markers in vivo. Neither L4F administration nor apoA-I overexpression affected glucose tolerance. ApoA-I overexpression significantly reduced atherosclerotic lesion size, yet L4F treatment did not affect atherosclerosis. Our results suggest that neither L4F (100 µg/day/mouse) nor apoA-I overexpression affects adiposity or insulin resistance in this model. We also were unable to confirm a reduction in atherosclerosis with L4F in our particular model. Further studies on the effect of apoA-I mimetics on atherosclerosis and insulin resistance in a variety of dietary contexts are warranted.

  5. The Apolipoprotein-AI Mimetic Peptide L4F at a Modest Dose Does Not Attenuate Weight Gain, Inflammation, or Atherosclerosis in LDLR-Null Mice

    PubMed Central

    Averill, Michelle M.; Kim, Eung Ju; Goodspeed, Leela; Wang, Shari; Subramanian, Savitha; Den Hartigh, Laura J.; Tang, Chongren; Ding, Yilei; Reardon, Catherine A.; Getz, Godfrey S.; Chait, Alan

    2014-01-01

    Objective High density lipoprotein (HDL) cholesterol levels are inversely related to cardiovascular disease risk and associated with a reduced risk of type 2 diabetes. Apolipoprotein A-I (apoA-I; major HDL protein) mimetics have been reported to reduce atherosclerosis and decrease adiposity. This study investigated the effect of L4F mimetic peptide and apoA-I overexpression on weight gain, insulin resistance, and atherosclerosis in an LDL receptor deficient (Ldlr-/-) model fed a high fat high sucrose with cholesterol (HFHSC) diet. Methods Studies in differentiated 3T3-L1 adipocytes tested whether L4F could inhibit palmitate-induced adipocyte inflammation. In vivo studies used male Ldlr-/- mice fed a HFHSC diet for 12 weeks and were injected daily with L4F (100 µg/mouse) subcutaneously during the last 8 weeks. Wild-type and apoA-I overexpressing Ldlr-/- mice were fed HFHSC diet for 16 weeks. Results Neither L4F administration nor apoA-I overexpression affected weight gain, total plasma cholesterol or triglycerides in our studies. While pre-treatment of 3T3-L1 adipocytes with either L4F or HDL abolished palmitate-induced cytokine expression in vitro, L4F treatment did not affect circulating or adipose tissue inflammatory markers in vivo. Neither L4F administration nor apoA-I overexpression affected glucose tolerance. ApoA-I overexpression significantly reduced atherosclerotic lesion size, yet L4F treatment did not affect atherosclerosis. Conclusion Our results suggest that neither L4F (100 µg/day/mouse) nor apoA-I overexpression affects adiposity or insulin resistance in this model. We also were unable to confirm a reduction in atherosclerosis with L4F in our particular model. Further studies on the effect of apoA-I mimetics on atherosclerosis and insulin resistance in a variety of dietary contexts are warranted. PMID:25286043

  6. BLDG. 37 - MICE

    NASA Image and Video Library

    1969-08-03

    S69-40752 (August 1969) --- Landrum Young, Brown and Root - Northrop technician examines mice in the Animal Laboratory of the Lunar Receiving Laboratory (LRL) which have been inoculated with lunar sample material. The sample material was collected by astronauts Neil A. Armstrong and Edwin E. Aldrin Jr. during their lunar surface extravehicular activity (EVA) on July 20, 1969.

  7. BLDG. 37 - MICE

    NASA Image and Video Library

    1969-08-03

    S69-40751 (August 1969) --- Landrum Young, Brown and Root - Northrop technician, examines mice in the Animal Laboratory of the Lunar Receiving Laboratory (LRL) which have been inoculated with lunar sample material. The sample material was collected by astronauts Neil A. Armstrong and Edwin E. Aldrin Jr. during their lunar surface extravehicular activity (EVA) on July 20, 1969.

  8. Mice and Men.

    ERIC Educational Resources Information Center

    Willingham, Shively; Thompson, Charles L.

    Observations and experiments with mice, developed and tested at the Pennsylvania Advancement School with underachieving boys in grades seven and eight, are described in this teachers' guide which includes copies of student worksheets for exercises needing them. In addition to lists of materials and procedural suggestions, ideas for guiding…

  9. Status of MICE

    SciTech Connect

    Soler, F. J. P.

    2010-03-30

    The Muon Ionization Cooling Experiment (MICE) is an experiment currently under construction at the Rutherford Appleton Laboratory (RAL) in the UK. The aim of the experiment is to demonstrate the concept of ionization cooling for a beam of muons, crucial for the requirements of a Neutrino Factory and a Muon Collider. Muon cooling is achieved by measuring the reduction of the four dimensional transverse emittance for a beam of muons passing through low density absorbers and then accelerating the longitudinal component of the momentum using RF cavities. The absorbers are maintained in a focusing magnetic field to reduce the betamore » function of the beam and the RF cavities are kept inside coupling coils. The main goal of MICE is to measure a fractional drop in emittance, of order -10% for large emittance beams, with an accuracy of 1%(which imposes a requirement that the absolute emittance be measured with an accuracy of 0.1%). This paper will discuss the status of MICE, including the progress in commissioning the muon beam line at the ISIS accelerator at RAL, the construction of the different detector elements in MICE and the prospects for the future.« less

  10. Colorful Kindergarten Mice

    ERIC Educational Resources Information Center

    Bobick, Bryna; Wheeler, Elizabeth

    2008-01-01

    Developing kindergarten lessons can be very challenging, especially at the beginning of the school year when many students are just learning to cut paper and hold crayons. The author's favorite beginning unit of the year is "mice paintings," a practical introduction to drawing, color theory, and painting. This unit also incorporates children's…

  11. The status of MICE

    NASA Astrophysics Data System (ADS)

    Liu, Ao; Muon Ionization Cooling Experiment (MICE) Collaboration

    2017-01-01

    Muon beams of low emittance provide the basis for the intense, well characterised neutrino beams of the Neutrino Factory and for lepton-antilepton collisions at energies of up to several TeV at the Muon Collider. The international Muon Ionization Cooling Experiment (MICE) will demonstrate ionization cooling, the technique by which it is proposed to reduce the phase-space volume occupied by the muon beam. MICE is being constructed in a series of Steps. The configuration currently in operation at the Rutherford Appleton Laboratory is optimised for the study the properties of liquid hydrogen and lithium hydride that affect cooling. The results that have recently been submitted for publication will be described along with preliminary results from the MICE study of the effect of liquid hydrogen and lithium hydride on the muon beam. The plans for data taking in the present configuration will be described together with a summary of the status of preparation of the final experimental configuration by which MICE will demonstrate the principle of ionization cooling.

  12. Annexin A2, autoimmunity, anxiety and depression.

    PubMed

    Weiss, R; Bitton, A; Ben Shimon, M; Elhaik Goldman, S; Nahary, L; Cooper, I; Benhar, I; Pick, C G; Chapman, J

    2016-09-01

    Antiphospholipid syndrome (APS) is associated with neurological manifestations and one of the novel autoantigens associated with this disease is Annexin A2 (ANXA2). In this work we have examined the effect of high levels of autoantibodies to ANXA2 on the brain in a mouse model. Recombinant ANXA2 emulsified in adjuvant was used to immunize mice while mice immunized with adjuvant only served as controls. At peak antibody levels the animal underwent behavioral and cognitive tests and their brains were examined for ANXA2 immunoglobulin G (IgG) and expression of ANXA2 and the closely linked protein p11. Very high levels of anti-ANXA2 antibodies (Abs) were associated with reduced anxiety in the open field 13.14% ± 0.89% of the time in the center compared to 8.64% ± 0.91% observed in the control mice (p < 0.001 by t-test). A forced swim test found significantly less depression manifested by immobility in the ANXA2 group. The changes in behavior were accompanied by a significant reduction in serum corticosteroid levels of ANXA2 group compared to controls. Moreover, higher levels of total IgG and p11 expression were found in ANXA2 group brains. Lower levels of circulating anti-ANXA2 Abs were not associated with behavioral changes. We have established an animal model with high levels of anti-ANXA2 Abs which induced IgG accumulation in the brain and specific anxiolytic and anti-depressive effects. This model promises to further our understanding of autoimmune disease such as APS and to provide better understanding of the role of the ANXA2-p11 complex in the brain. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Mice Drawer System

    NASA Technical Reports Server (NTRS)

    Cancedda, Ranieri

    2008-01-01

    The Mice Drawer System (MDS) is an Italian Space Agency (ASI) facility which is able to support mice onboard the International Space Station during long-duration exploration missions (from 100 to 150-days) by living space, food, water, ventilation and lighting. Mice can be accommodated either individually (maximum 6) or in groups (4 pairs). MDS is integrated in the Space Shuttle middeck during transportation (uploading and downloading) to the ISS and in an EXPRESS Rack in Destiny, the US Laboratory during experiment execution. Osteoporosis is a debilitating disease that afflicts millions of people worldwide. One of the physiological changes experienced by astronauts during space flight is the accelerated loss of bone mass due to the lack of gravitational loading on the skeleton. This bone loss experienced by astronauts is similar to osteoporosis in the elderly population. MDS will help investigate the effects of unloading on transgenic (foreign gene that has been inserted into its genome to exhibit a particular trait) mice with the Osteoblast Stimulating Factor-1, OSF-1, a growth and differentiation factor, and to study the genetic mechanisms underlying the bone mass pathophysiology. MDS will test the hypothesis that mice with an increased bone density are likely to be more protected from osteoporosis, when the increased bone mass is a direct effect of a gene involved in skeletogenesis (skeleton formation). Osteoporosis is a debilitating disease that afflicts millions worldwide. One of the physiological changes experienced by astronauts during space flight is the accelerated loss of bone mass due to the lack of gravitational loading on the skeleton, a loss that is similar to osteoporosis in the elderly population on Earth. Osteoblast Stimulating Factor-1 (OSF-1), also known as pleiotrophin (PTN) or Heparin-Binding Growth- Associated Molecule (HB-GAM) belongs to a family of secreted heparin binding proteins..OSF-1 is an extracellular matrix-associated growth and

  14. The Status of MICE

    NASA Astrophysics Data System (ADS)

    Dobbs, A. J.; MICE Collaboration

    2017-09-01

    Muon beams of low emittance provide the basis for the intense, well characterised neutrino beams for a Neutrino Factory and for lepton-antilepton collisions at energies of up to several TeV at a Muon Collider. The international Muon Ionization Cooling Experiment (MICE) will demonstrate ionization cooling, the technique by which it is proposed to reduce the phase-space volume occupied by the muon beam. MICE is being constructed in a series of Steps. The configuration currently in operation at the Rutherford Appleton Laboratory is optimised for the study of the properties of liquid hydrogen and lithium hydride that affect cooling. The plans for data taking in the present configuration will be described together with some preliminary results. A description of the next experimental configuration, used for the final cooling demonstration, is also presented.

  15. Experimental Paracoccidioidomycosis in Mice

    PubMed Central

    Linares, Leonor I.; Friedman, Lorraine

    1972-01-01

    Virulence and infectivity of nine strains of Paracoccidioides brasiliensis were investigated in groups of mice which were inoculated intranasally or intravenously, and some of each were treated with corticosteroids. Fatal infections were not often seen among untreated mice, but mortality usually occurred when corticosteroids were given, regardless of the route of fungus inoculation. Prior treatment did not uniformly increase the incidence of infection, however; only in the case of intranasally inoculated mice was this effect seen. Most strains appeared to be more virulent when administered intravenously, with the exception of a single strain which, under the influence of corticosteroids, repeatedly displayed greatest virulence when given intranasally. All animals that died early in the course of the disease, irrespective of route of inoculation, always had acute pulmonary lesions and usually no other organ was involved. Animals which died later or were sacrificed always had chronic lung lesions. Whether or not chronically diseased animals had additional organ involvement correlated with how the organisms were administered; intravenously inoculated animals usually had extrapulmonary as well as pulmonary lesions, but lesions of those inoculated intranasally were almost exclusively pulmonary. Corticosteroids did not alter the histologic characteristics of either the acute or the chronic type of lesion, but the lesions of treated animals were usually more extensive. Most of the survivors appeared healthy even when infection was extensive. Images PMID:4637603

  16. Obese Mice Losing Weight Due to trans-10,cis-12 Conjugated Linoleic Acid Supplementation or Food Restriction Harbor Distinct Gut Microbiota.

    PubMed

    den Hartigh, Laura J; Gao, Zhan; Goodspeed, Leela; Wang, Shari; Das, Arun K; Burant, Charles F; Chait, Alan; Blaser, Martin J

    2018-04-01

    trans-10,cis-12 Conjugated linoleic acid (t10,c12-CLA) is a dietary supplement that promotes weight loss by increasing fat oxidation and energy expenditure. We previously reported that in the absence of t10,c12-CLA, mice forced to lose equivalent body weight by food restriction (FR) do not exhibit increases in fat oxidation or energy expenditure but have improved glucose metabolism, consistent with FR as a metabolically healthy weight-loss method. Because diet is a primary determinant of gut bacterial populations, we hypothesized that the disparate metabolic effects accompanying weight loss from t10,c12-CLA or FR could be related to altered intestinal microbiota. Ten-week-old male LDL receptor-deficient (Ldlr-/-) mice were fed a high-fat, high-sucrose diet (HFHS; 36% lard fat, 36.2% sucrose + 0.15% cholesterol) for 12 wk (baseline), then switched to the HFHS diet alone (obese control), HFHS + 1% c9,t11-CLA (obese fatty acid control), HFHS + 1% t10,c12-CLA (weight-loss-inducing fatty acid), or HFHS + FR (weight-loss control group with 75-85% ad libitum HFHS food intake) for a further 8 wk. Fecal microbial content, short-chain fatty acids (butyrate, acetate), tissue CLA concentrations, and intestinal nutrient transporter expression were quantified. Mice fed t10,c12-CLA or assigned to FR lost 14.5% of baseline body weight. t10,c12-CLA-fed mice had elevated concentrations of fecal butyrate (2-fold) and plasma acetate (1.5-fold) compared with HFHS-fed controls. Fecal α diversity decreased by 7.6-14% in all groups. Butyrivibrio and Roseburia, butyrate-producing microbes, were enriched over time by t10,c12-CLA. By comparing with each control group, we also identified bacterial genera significantly enriched in the t10,c12-CLA recipients, including Lactobacillus, Actinobacteria, and the newly identified Ileibacterium valens of the Allobaculum genus, whereas other taxa were enriched by FR, including Clostridiales and Bacteroides. Modalities resulting in equivalent

  17. Endotracheal intubation in mice via direct laryngoscopy using an otoscope.

    PubMed

    Thomas, Joanna L; Dumouchel, Justin; Li, Jinghong; Magat, Jenna; Balitzer, Dana; Bigby, Timothy D

    2014-04-05

    Mice, both wildtype and transgenic, are the principal mammalian model in biomedical research currently. Intubation and mechanical ventilation are necessary for whole animal experiments that require surgery under deep anesthesia or measurements of lung function. Tracheostomy has been the standard for intubating the airway in these mice to allow mechanical ventilation. Orotracheal intubation has been reported but has not been successfully used in many studies because of the substantial technical difficulty or a requirement for highly specialized and expensive equipment. Here we report a technique of direct laryngoscopy using an otoscope fitted with a 2.0 mm speculum and using a 20 G intravenous catheter as an endotracheal tube. We have used this technique extensively and reliably to intubate and conduct accurate assessments of lung function in mice. This technique has proven safe, with essentially no animal loss in experienced hands. Moreover, this technique can be used for repeated studies of mice in chronic models.

  18. Endotracheal Intubation in Mice via Direct Laryngoscopy Using an Otoscope

    PubMed Central

    Thomas, Joanna L.; Dumouchel, Justin; Li, Jinghong; Magat, Jenna; Balitzer, Dana; Bigby, Timothy D.

    2014-01-01

    Mice, both wildtype and transgenic, are the principal mammalian model in biomedical research currently. Intubation and mechanical ventilation are necessary for whole animal experiments that require surgery under deep anesthesia or measurements of lung function. Tracheostomy has been the standard for intubating the airway in these mice to allow mechanical ventilation. Orotracheal intubation has been reported but has not been successfully used in many studies because of the substantial technical difficulty or a requirement for highly specialized and expensive equipment. Here we report a technique of direct laryngoscopy using an otoscope fitted with a 2.0 mm speculum and using a 20 G intravenous catheter as an endotracheal tube. We have used this technique extensively and reliably to intubate and conduct accurate assessments of lung function in mice. This technique has proven safe, with essentially no animal loss in experienced hands. Moreover, this technique can be used for repeated studies of mice in chronic models. PMID:24747695

  19. Alleviating VLDL overproduction is an important mechanism for Laminaria japonica polysaccharide to inhibit atherosclerosis in LDLr-/-mice with diet-induced insulin resistance.

    PubMed

    Zha, Xue-Qiang; Zhang, Wei-Nan; Peng, Fu-Hua; Xue, Lei; Liu, Jian; Luo, Jian-Ping

    2017-04-01

    The overproduction of very low density lipoprotein (VLDL) is an important cause for initiation and development of atherosclerosis, which is highly associated with insulin signaling. The aim of this work is to verify whether the inhibition of VLDL overproduction is an underlying mechanism for a Laminaria japonica polysaccharide (LJP61A (where LJP is L. japonica)) to resist atherosclerosis. LJP61A (50 and 200 mg/kg/day) was orally administered to a high-fat diet (HFD)-fed LDL receptor deficient mice for 14 weeks. LJP61A significantly attenuated insulin resistance, hepatic steatosis, atherosclerosis, and dyslipidemia. Meanwhile, LJP61A ameliorated the HFD-induced impairment of hepatic insulin signaling and reduced VLDL overproduction via regulating the expression of genes involved in the assembly and secretion of VLDL. To study the possibility that the inhibition of mammalian target of rapamycin complex 1 and stimulation of Forkhead box protein O1 (Foxo1) nuclear exclusion is a result of LJP61A via regulating insulin signaling, LJP61A was administrated to HepG2 cells in the presence or absence of mTOR inhibitor and Foxo1 inhibitor. Results showed that LJP61A alleviated VLDL overproduction via regulating insulin receptor substrate mediated phosphatidylinositide 3-kinase AKT mammalian target of rapamycin complex 1 and phosphatidylinositide 3-kinase AKT-Foxo1 signaling pathways. These results suggested that LJP61A ameliorated HFD-induced insulin resistance to attenuate VLDL overproduction possibly via regulating insulin signaling, leading to the inhibition of atherosclerosis. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Genetic variation in Surfactant Protein-A2 (SP-A2) leads to differential binding to Mycoplasma pneumoniae membranes and regulation of host responses

    PubMed Central

    Ledford, Julie G.; Voelker, Dennis R.; Addison, Kenneth J.; Wang, Ying; Nikam, Vinayak; Degan, Simone; Kandasamy, Pitachaimani; Tanyaratsrisakul, Sasipa; Fischer, Bernard M.; Kraft, Monica; Hollingsworth, John W.

    2015-01-01

    Mycoplasma pneumoniae (Mp) is an extracellular pathogen that colonizes mucosal surfaces of the respiratory tract and is associated with asthma exacerbations. Previous reports demonstrate that surfactant protein-A (SP-A) binds live Mp and mycoplasma membranes (MMF) with high affinity. Humans express a repertoire of single amino acid genetic variants of SP-A that may be associated with lung disease, and our findings demonstrate that allelic differences in SP-A2 (Gln223Lys) affect the binding to MMF. We show that SP-A−/− mice are more susceptible to MMF exposure and have significant increases in mucin production and neutrophil recruitment. Novel humanized-SP-A2 transgenic mice harboring the hSP-A2 223K allele exhibit reduced neutrophil influx and mucin production in the lungs, when challenged with MMF, compared to SP-A−/− mice. Conversely, mice expressing hSP-A2 223Q have increased neutrophil influx and mucin production that is similar to SP-A−/− mice. Using tracheal epithelial cell cultures, we show that enhanced mucin production to MMF occurs in the absence of SP-A, and is not dependent upon neutrophil recruitment. Increased phosphorylation of the epidermal growth factor receptor (EGFR) was evident in the lungs of MMF-challenged mice when SP-A was absent. Pharmacologic inhibition of EGFR prior to MMF challenge dramatically reduced mucin production in SP-A−/− mice. These findings suggest a protective role for SP-A in limiting MMF-stimulated mucin production that occurs through interference with EGFR mediated signaling. The SP-A interaction with the EGFR signaling pathway appears to occur in an allele specific manner that may have important implications for SP-A polymorphisms in human diseases. PMID:25957169

  1. Sublingual immunotherapy in sensitized mice.

    PubMed

    Kildsgaard, Jens; Brimnes, Jens; Jacobi, Henrik; Lund, Kaare

    2007-04-01

    Many studies have demonstrated immunologic changes induced by sublingual immunotherapy (SLIT), but the definitive mechanism of action needs further investigation. To study the immunologic response induced by SLIT in sensitized mice. Timothy grass (Phleum pratense)-sensitized mice received SLIT for 2, 4, or 6 weeks at 3 different concentrations, including a buffer control. Serum samples and washes of the lungs (bronchoalveolar lavage [BAL]) and the nasal passages (nasal lavage [NAL]) were analyzed for allergen-specific antibodies. T cells were isolated from the spleen and cervical lymph nodes for the analysis of proliferation and cytokine production. Sublingual immunotherapy in sensitized mice resulted in a 30-fold increase in antigen specific IgA levels in BAL and NAL fluid compared with buffer-treated mice, whereas antigen specific IgE was undetectable in BAL and NAL fluid in animals treated with SLIT. Furthermore, IgA levels were proportional to the dose and duration of SLIT. Levels of specific IgA in serum correlated with levels in BAL and NAL fluid. Serum IgA levels were proportional to the duration of allergen exposure to the oral mucosa. Conversely, no changes in serum levels of IgE and IgG were induced by SLIT. Proliferation of T cells was increased in mice treated with SLIT compared with nontreated mice. High levels of IgA in serum and in BAL and NAL fluid of mice treated with SLIT demonstrate that SLIT induces a mucosal, nonallergic response in sensitized mice.

  2. Atp1a2 Contributes Modestly to Alcohol-Related Behaviors

    PubMed Central

    Gritz, Stephanie M.; Larson, Colin; Radcliffe, Richard A.

    2016-01-01

    Atp1a2 has been previously studied for anxiety, learning and motor function disorders, and fear. Since Atp1a2 has been shown to be involved in anxiety and this behavior is a known risk factor for developing alcoholism, we have been investigating Atp1a2 for its potential role in responses to alcohol. This study utilized Atp1a2 knockout mice; Atp1a2 heterozygous mice, with half the amount of protein compared to wild-type mice, were used because Atp1a2 homozygous null mice die shortly after birth. The alcohol-related behavioral experiments performed were loss of righting reflex (LORR), acute alcohol withdrawal measured by handling-induced convulsions (HIC), drinking in the dark (DID), open-field activity (OFA), and elevated plus-maze (EPM). LORR was a 2-day test that measures acute alcohol sensitivity, and rapid and acute functional tolerance (AFT). HIC was a 3-day test to measure alcohol withdrawal, DID was a 4-day test which measures voluntary alcohol consumption, and OFA and EPM measured anxiety with alcohol exposure. The effect of genotype on alcohol metabolism was also examined. There was a genotype effect on rate of alcohol metabolism, but only in males. There was no effect on alcohol withdrawal severity. The Atp1a2 heterozygous mice consumed more alcohol than wild-type mice in the DID test, although only in males. In addition, only males were observed to show rapid tolerance in the LORR test while only female heterozygous mice showed a pretreatment effect on AFT. Alcohol exposure had a greater anxiolytic effect in the heterozygous mice compared to wild-type mice, although, again, there were sex effects with only males showing the effect in OFA and only females in the EPM. Although the behavioral results were mixed, there does appear to be a connection between anxiety and alcohol. Overall, the results suggest that Atp1a2 does contribute to alcohol-related behaviors, although the effect is modest with a clear dependence on sex. PMID:27814792

  3. Influence of Ovarian Hormones on Strength Loss in Healthy and Dystrophic Female Mice

    PubMed Central

    Kosir, Allison M.; Mader, Tara L.; Greising, Angela G.; Novotny, Susan A.; Baltgalvis, Kristen A.; Lowe, Dawn A.

    2014-01-01

    Purpose The primary objective of this study was to determine if strength loss and recovery following eccentric contractions is impaired in healthy and dystrophic female mice with low levels of ovarian hormones. Methods Female C57BL/6 (wildtype) or mdx mice were randomly assigned to ovarian-intact (Sham) and ovariectomized (Ovx) groups. Anterior crural muscles were tested for susceptibility to injury from 150 or 50 eccentric contractions in wildtype and mdx mice, respectively. An additional experiment challenged mdx mice with a 2-wk treadmill running protocol followed by an eccentric contraction injury to posterior crural muscles. Functional recovery from injury was evaluated in wildtype mice by measuring isometric torque 3, 7, 14, or 21 days following injury. Results Ovarian hormone deficiency in wildtype mice did not impact susceptibility to injury as the ~50% isometric torque loss following eccentric contractions did not differ between Sham and Ovx mice (p=0.121). Similarly in mdx mice, hormone deficiency did not affect percent of pre injury isometric torque lost by anterior crural muscles following eccentric contractions (p=0.952), but the percent of pre injury torque in posterior crural muscles was lower in Ovx compared to Sham mice (p=0.014). Recovery from injury in wildtype mice was affected by hormone deficiency. Sham mice recovered pre injury isometric strength by 14 days (96 ± 2%) while Ovx mice maintained deficits at 14 and 21 days post injury (80 ± 3% and 84 ± 2%; p<0.001) Conclusion Ovarian hormone status did not impact the vulnerability of skeletal muscle to strength loss following eccentric contractions. However, ovarian hormone deficiency did impair the recovery of muscle strength in female mice. PMID:25255128

  4. Resilience in Aging Mice.

    PubMed

    Kirkland, James L; Stout, Michael B; Sierra, Felipe

    2016-11-01

    Recently discovered interventions that target fundamental aging mechanisms have been shown to increase life span in mice and other species, and in some cases, these same manipulations have been shown to enhance health span and alleviate multiple age-related diseases and conditions. Aging is generally associated with decreases in resilience, the capacity to respond to or recover from clinically relevant stresses such as surgery, infections, or vascular events. We hypothesize that the age-related increase in susceptibility to those diseases and conditions is driven by or associated with the decrease in resilience. Thus, a test for resilience at middle age or even earlier could represent a surrogate approach to test the hypothesis that an intervention delays the process of aging itself. For this, animal models to test resilience accurately and predictably are needed. In addition, interventions that increase resilience might lead to treatments aimed at enhancing recovery following acute illnesses, or preventing poor outcomes from medical interventions in older, prefrail subjects. At a meeting of basic researchers and clinicians engaged in research on mechanisms of aging and care of the elderly, the merits and drawbacks of investigating effects of interventions on resilience in mice were considered. Available and potential stressors for assessing physiological resilience as well as the notion of developing a limited battery of such stressors and how to rank them were discussed. Relevant ranking parameters included value in assessing general health (as opposed to focusing on a single physiological system), ease of use, cost, reproducibility, clinical relevance, and feasibility of being repeated in the same animal longitudinally. During the discussions it became clear that, while this is an important area, very little is known or established. Much more research is needed in the near future to develop appropriate tests of resilience in animal models within an aging context

  5. Enhancing chemotherapy response with sustained EphA2 silencing using multistage vector delivery

    PubMed Central

    Shen, Haifa; Rodriguez-Aguayo, Cristian; Xu, Rong; Gonzalez-Villasana, Vianey; Mai, Junhua; Huang, Yi; Zhang, Guodong; Guo, Xiaojing; Bai, Litao; Qin, Guoting; Deng, Xiaoyong; Li, Qingpo; Erm, Donald R.; Liu, Xuewu; Sakamoto, Jason; Chavez-Reyes, Arturo; Han, Hee-Dong; Sood, Anil K.; Ferrari, Mauro; Lopez-Berestein, Gabriel

    2013-01-01

    Purpose RNA interference has the potential to specifically knock down the expression of target genes, and thereby transform cancer therapy. However, lack of effective delivery of small inhibitory RNA (siRNA) has dramatically limited its in vivo applications. We have developed a multistage vector (MSV) system, composed of discoidal porous silicon particles loaded with nanotherapeutics, that directs effective delivery and sustained release of siRNA in tumor tissues. In this study, we evaluated therapeutic efficacy of MSV-loaded EphA2 siRNA (MSV/EphA2) with murine orthotopic models of metastatic ovarian cancers as a first step towards development of a new class of nanotherapeutics for the treatment of ovarian cancer. Experimental design Tumor accumulation of MSV/EphA2 and sustained release of siRNA from MSV were analyzed after i.v. administration of MSV/siRNA. Nude mice with metastatic SKOV3ip2 tumors were treated with MSV/EphA2 and paclitaxel, and therapeutic efficacy was assessed. Mice with chemotherapy-resistant HeyA8 ovarian tumors were treated with a combination of MSV/EphA2 and docetaxel, and enhanced therapeutic efficacy was evaluated. Results Treatment of SKOV3ip2 tumor mice with MSV/EphA2 biweekly for 6 weeks resulted in dose-dependent (5, 10 and 15 μg/mice) reduction of tumor weight (36%, 64%, and 83%) and number of tumor nodules compared with the control groups. In addition, tumor growth was completely inhibited when mice were treated with MSV/EphA2 in combination with paclitaxel. Furthermore, combination treatment with MSV/EphA2 and docetaxel inhibited growth of HeyA8-MDR tumors, which were otherwise resistant to docetaxel treatment. Conclusion These findings indicate that MSV/EphA2 merits further development as a novel therapeutic agent for ovarian cancer. PMID:23386691

  6. Enhancing chemotherapy response with sustained EphA2 silencing using multistage vector delivery.

    PubMed

    Shen, Haifa; Rodriguez-Aguayo, Cristian; Xu, Rong; Gonzalez-Villasana, Vianey; Mai, Junhua; Huang, Yi; Zhang, Guodong; Guo, Xiaojing; Bai, Litao; Qin, Guoting; Deng, Xiaoyong; Li, Qingpo; Erm, Donald R; Aslan, Burcu; Liu, Xuewu; Sakamoto, Jason; Chavez-Reyes, Arturo; Han, Hee-Dong; Sood, Anil K; Ferrari, Mauro; Lopez-Berestein, Gabriel

    2013-04-01

    RNA interference has the potential to specifically knockdown the expression of target genes and thereby transform cancer therapy. However, lack of effective delivery of siRNA has dramatically limited its in vivo applications. We have developed a multistage vector (MSV) system, composed of discoidal porous silicon particles loaded with nanotherapeutics, that directs effective delivery and sustained release of siRNA in tumor tissues. In this study, we evaluated therapeutic efficacy of MSV-loaded EphA2 siRNA (MSV/EphA2) with murine orthotopic models of metastatic ovarian cancers as a first step toward development of a new class of nanotherapeutics for the treatment of ovarian cancer. Tumor accumulation of MSV/EphA2 and sustained release of siRNA from MSV were analyzed after intravenous administration of MSV/siRNA. Nude mice with metastatic SKOV3ip2 tumors were treated with MSV/EphA2 and paclitaxel, and therapeutic efficacy was assessed. Mice with chemotherapy-resistant HeyA8 ovarian tumors were treated with a combination of MSV/EphA2 and docetaxel, and enhanced therapeutic efficacy was evaluated. Treatment of SKOV3ip2 tumor mice with MSV/EphA2 biweekly for 6 weeks resulted in dose-dependent (5, 10, and 15 μg/mice) reduction of tumor weight (36%, 64%, and 83%) and number of tumor nodules compared with the control groups. In addition, tumor growth was completely inhibited when mice were treated with MSV/EphA2 in combination with paclitaxel. Furthermore, combination treatment with MSV/EphA2 and docetaxel inhibited growth of HeyA8-MDR tumors, which were otherwise resistant to docetaxel treatment. These findings indicate that MSV/EphA2 merits further development as a novel therapeutic agent for ovarian cancer. ©2013 AACR.

  7. GLP-2 receptor deficiency in the mouse brain impairs glucose homeostasis

    USDA-ARS?s Scientific Manuscript database

    In response to food intake, glucagon-like peptide-2 (GLP-2) with GLP-1 is co-secreted from enteroendocrine L cells in the gut. GLP-2 receptor (GLP-2R) is expressed in the hypothalamus, a key tissue to integrate energy signals to regulate energy balance and glucose homeostasis. However, the physiolog...

  8. Characterization of Ebola virus entry by using pseudotyped viruses: identification of receptor-deficient cell lines.

    PubMed

    Wool-Lewis, R J; Bates, P

    1998-04-01

    Studies analyzing Ebola virus replication have been severely hampered by the extreme pathogenicity of this virus. To permit analysis of the host range and function of the Ebola virus glycoprotein (Ebo-GP), we have developed a system for pseudotyping these glycoproteins into murine leukemia virus (MLV). This pseudotyped virus, MLV(Ebola), can be readily concentrated to titers which exceed 5 x 10(6) infectious units/ml and is effectively neutralized by antibodies specific for Ebo-GP. Analysis of MLV(Ebola) infection revealed that the host range conferred by Ebo-GP is very broad, extending to cells of a variety of species. Notably, all lymphoid cell lines tested were completely resistant to infection; we speculate that this is due to the absence of a cellular receptor for Ebo-GP on B and T cells. The generation of high-titer MLV(Ebola) pseudotypes will be useful for the analysis of immune responses to Ebola virus infection, development of neutralizing antibodies, analysis of glycoprotein function, and isolation of the cellular receptor(s) for the Ebola virus.

  9. The daidzein- and estradiol- induced anorectic action in CCK or leptin receptor deficiency rats.

    PubMed

    Fujitani, Mina; Mizushige, Takafumi; Bhattarai, Keshab; Iwahara, Asami; Aida, Ryojiro; Kishida, Taro

    2015-01-01

    We investigated the effect of daidzein feeding and estradiol treatment on food intake in cholecystokinin-1 receptor (CCK1R) deficiency, leptin receptor (ObRb) deficiency rats and their wild-type rats. These rats underwent an ovariectomy or a sham operation. For the 5 week experiment, each rat was divided in three groups: control, daidzein (150 mg/kg diet), and estradiol (4.2 μg/rat/day) groups. In both CCK1R+ and CCK1R- rats, daidzein feeding and estradiol treatment significantly decreased food intake. Daidzein feeding significantly reduced food intake in ovariectomized ObRb- rats, although not in ObRb+ rats. Estradiol treatment significantly lowered food intake in ovariectomized ObRb+ and ObRb- rats. In the ovariectomized rats, estradiol treatment significantly increases uterine weight, while daidzein feeding did not change it, suggesting that daidzein might have no or weak estrogenic effect in our experiment. These results suggest that CCK1R and ObRb signalings were not essential for the daidzein- and estradiol-induced anorectic action.

  10. Leptin Receptor Deficiency is Associated With Upregulation of Cannabinoid 1 Receptors in Limbic Brain Regions

    PubMed Central

    THANOS, PANAYOTIS K.; RAMALHETE, ROBERTO C.; MICHAELIDES, MICHAEL; PIYIS, YIANNI K.; WANG, GENE-JACK; VOLKOW, NORA D.

    2009-01-01

    Leptin receptor dysfunction results in overeating and obesity. Leptin regulates hypothalamic signaling that underlies the motivation to hyperphagia, but the interaction between leptin and cannabinoid signaling is poorly understood. We evaluated the role of cannabinoid 1 receptors (CB1R) in overeating and the effects of food deprivation on CB1R in the brain. One-month-old Zucker rats were divided into unrestricted and restricted (fed 70% of unrestricted rats) diet groups and maintained until adulthood (4 months). Levels of relative binding sites of CB1R (CB1R binding levels) were assessed using [3H] SR141716A in vitro autoradiography. These levels were higher (except cerebellum and hypothalamus) at 4 months than at 1 month of age. One month CB1R binding levels for most brain regions did not differ between Ob and Lean (Le) rats (except in frontal and cingulate cortices in Le and in the hypothalamus in Ob). Four month Ob rats had higher CB1R binding levels than Le in most brain regions and food restriction was associated with higher CB1R levels in all brain regions in Ob, but not in Le rats. CB1R binding levels increased between adolescence and young adulthood which we believe was influenced by leptin and food availability. The high levels of CB1R in Ob rats suggest that leptin's inhibition of food-intake is in part mediated by downregulation of CB1R and that leptin interferes with CB1R upregulation under food-deprivation conditions. These results are consistent with prior findings showing increased levels of endogenous cannabinoids in the Ob rats corroborating the regulation of cannabinoid signaling by leptin. PMID:18563836

  11. Owls and Larks in Mice

    PubMed Central

    Pfeffer, Martina; Wicht, Helmut; von Gall, Charlotte; Korf, Horst-Werner

    2015-01-01

    Humans come in different chronotypes and, particularly, the late chronotype (the so-called owl) has been shown to be associated with several health risks. A number of studies show that laboratory mice also display various chronotypes. In mice as well as in humans, the chronotype shows correlations with the period length and rhythm stability. In addition, some mouse models for human diseases show alterations in their chronotypic behavior, which are comparable to those humans. Thus, analysis of the behavior of mice is a powerful tool to unravel the molecular and genetic background of the chronotype and the prevalence of risks and diseases that are associated with it. In this review, we summarize the correlation of chronotype with free-running period length and rhythm stability in inbred mouse strains, in mice with a compromised molecular clockwork, and in a mouse model for neurodegeneration. PMID:26029157

  12. The MICE Muon Beam Line

    NASA Astrophysics Data System (ADS)

    Apollonio, Marco

    2011-10-01

    In the Muon Ionization Cooling Experiment (MICE) at RAL, muons are produced and transported in a dedicated beam line connecting the production point (target) to the cooling channel. We discuss the main features of the beamline, meant to provide muons with momenta between 140 MeV/c and 240 MeV/c and emittances up to 10 mm rad, which is accomplished by means of a diffuser. Matching procedures to the MICE cooling channel are also described. In summer 2010 we performed an intense data taking campaign to finalize the calibration of the MICE Particle Identification (PID) detectors and the understanding of the beam line, which completes the STEPI phase of MICE. We highlight the main results from these data.

  13. Rapamycin slows aging in mice.

    PubMed

    Wilkinson, John E; Burmeister, Lisa; Brooks, Susan V; Chan, Chi-Chao; Friedline, Sabrina; Harrison, David E; Hejtmancik, James F; Nadon, Nancy; Strong, Randy; Wood, Lauren K; Woodward, Maria A; Miller, Richard A

    2012-08-01

    Rapamycin increases lifespan in mice, but whether this represents merely inhibition of lethal neoplastic diseases, or an overall slowing in multiple aspects of aging is currently unclear. We report here that many forms of age-dependent change, including alterations in heart, liver, adrenal glands, endometrium, and tendon, as well as age-dependent decline in spontaneous activity, occur more slowly in rapamycin-treated mice, suggesting strongly that rapamycin retards multiple aspects of aging in mice, in addition to any beneficial effects it may have on neoplastic disease. We also note, however, that mice treated with rapamycin starting at 9 months of age have significantly higher incidence of testicular degeneration and cataracts; harmful effects of this kind will guide further studies on timing, dosage, and tissue-specific actions of rapamycin relevant to the development of clinically useful inhibitors of TOR action. © 2012 The Authors. Aging Cell © 2012 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland.

  14. Transgenic mice in developmental toxicology

    SciTech Connect

    Woychik, R.P.

    1992-01-01

    Advances in molecular biology and embryology are being utilized for the generation of transgenic mice, animals that contain specific additions, deletions, or modifications of genes or sequences in their DNA. Mouse embryonic stem cells and homologous recombination procedures have made it possible to target specific DNA structural alterations to highly localized region in the host chromosomes. The majority of the DNA structural rearrangements in transgenic mice can be passed through the germ line and used to establish new genetic traits in the carrier animals. Since the use of transgenic mice is having such an enormous impact on so many areasmore » of mammalian biological research, including developmental toxicology, the objective of this review is to briefly describe the fundamental methodologies for generating transgenic mice and to describe one particular application that has direct relevance to the field of genetic toxicology.« less

  15. Transgenic mice in developmental toxicology

    SciTech Connect

    Woychik, R.P.

    1992-12-31

    Advances in molecular biology and embryology are being utilized for the generation of transgenic mice, animals that contain specific additions, deletions, or modifications of genes or sequences in their DNA. Mouse embryonic stem cells and homologous recombination procedures have made it possible to target specific DNA structural alterations to highly localized region in the host chromosomes. The majority of the DNA structural rearrangements in transgenic mice can be passed through the germ line and used to establish new genetic traits in the carrier animals. Since the use of transgenic mice is having such an enormous impact on so many areasmore » of mammalian biological research, including developmental toxicology, the objective of this review is to briefly describe the fundamental methodologies for generating transgenic mice and to describe one particular application that has direct relevance to the field of genetic toxicology.« less

  16. Visual Selective Attention in Mice.

    PubMed

    Wang, Lupeng; Krauzlis, Richard J

    2018-03-05

    Visual selective attention is a fundamental cognitive ability that allows us to process relevant visual stimuli while ignoring irrelevant distracters and has been extensively studied in human and non-human primate subjects. Mice have emerged as a powerful animal model for studying aspects of the visual system but have not yet been shown to exhibit visual selective attention. Differences in the organization of the visual systems of primates and mice raise the possibility that selective visual attention might not be present in mice, at least not in the forms that are well established in primates. Here, we tested for selective visual attention in mice by using three behavioral paradigms adapted from classic studies of attention. In a Posner-style cueing task, a spatial cue indicated the probable location of the relevant visual event, and we found that accuracy was higher and reaction times were shorter on validly cued trials. In a cue versus no-cue task, an informative spatial cue was provided on half the trials, and mice had higher accuracy and shorter reaction times with spatial cues and also lower detection thresholds measured from psychometric curves. In a filter task, the spatial cue indicated the location of the relevant visual event, and we found that mice could be trained to ignore irrelevant but otherwise identical visual events at uncued locations. Together, these results demonstrate that mice exhibit visual selective attention, paving the way to use classic attention paradigms in mice to study the genetic and neuronal circuit mechanisms of selective attention. Published by Elsevier Ltd.

  17. Group 1B Phospholipase A2–Mediated Lysophospholipid Absorption Directly Contributes to Postprandial Hyperglycemia

    PubMed Central

    Labonté, Eric D.; Kirby, R. Jason; Schildmeyer, Nicholas M.; Cannon, April M.; Huggins, Kevin W.; Hui, David Y.

    2007-01-01

    Postprandial hyperglycemia is an early indicator of abnormality in glucose metabolism leading to type 2 diabetes. However, mechanisms that contribute to postprandial hyperglycemia have not been identified. This study showed that mice with targeted inactivation of the group 1B phospholipase A2 (Pla2g1b) gene displayed lower postprandial glycemia than that observed in wild-type mice after being fed a glucose-rich meal. The difference was caused by enhanced postprandial glucose uptake by the liver, heart, and muscle tissues as well as altered postprandial hepatic glucose metabolism in the Pla2g1b−/ − mice. These differences were attributed to a fivefold decrease in the amount of dietary phospholipids absorbed as lysophospholipids in Pla2g1b−/− mice compared with that observed in Pla2g1b+/+ mice. Elevating plasma lysophospholipid levels in Pla2g1b−/− mice via intraperitoneal injection resulted in glucose intolerance similar to that exhibited by Pla2g1b+/+mice. Studies with cultured hepatoma cells revealed that lysophospholipids dose-dependently suppressed insulin-stimulated glycogen synthesis. These results demonstrated that reduction of lysophospholipid absorption enhances insulin-mediated glucose metabolism and is protective against postprandial hyperglycemia. PMID:16567514

  18. Deer Mice As Laboratory Animals.

    PubMed

    Joyner, Charlotte P.; Myrick, Lisa C.; Crossland, Janet P.; Dawson, Wallace D.

    1998-09-01

    Although laboratory mice (Mus) and rats (Rattus) are the most widely used research rodents, deer mice (Peromyscus maniculatus) and their congeneric species are favored as nontraditional alternatives for some purposes. Mice of the native genus Peromyscus are the most abundant and widely distributed rodents in North America. They occur in a great diversity of habitats and play a significant role in natural ecosystems. Because of their abundance, peromyscines are commonly hosts for larva of ticks that transmit Lyme disease bacteria, and they are implicated in several other vector-borne diseases. Deer mice also are the principal carriers of the virus that causes hantaviral pulmonary syndrome, or "Four Corners disease." Deer mice are useful as laboratory models for a variety of other types of pure and applied research. They are easily maintained and bred in captivity using the husbandry protocols developed for other small laboratory rodent species. The Peromyscus Genetic Stock Center at the University of South Carolina maintains more than 50 laboratory-bred, well-characterized stocks of deer mice and other peromyscine species for research and educational use.

  19. Neuroprotection by caffeine in the MPTP model of parkinson's disease and its dependence on adenosine A2A receptors.

    PubMed

    Xu, K; Di Luca, D G; Orrú, M; Xu, Y; Chen, J-F; Schwarzschild, M A

    2016-05-13

    Considerable epidemiological and laboratory data have suggested that caffeine, a nonselective adenosine receptor antagonist, may protect against the underlying neurodegeneration of parkinson's disease (PD). Although both caffeine and more specific antagonists of the A2A subtype of adenosine receptor (A2AR) have been found to confer protection in animal models of PD, the dependence of caffeine's neuroprotective effects on the A2AR is not known. To definitively determine its A2AR dependence, the effect of caffeine on 1-methyl-4-phenyl-1,2,3,6 tetra-hydropyridine (MPTP) neurotoxicity was compared in wild-type (WT) and A2AR gene global knockout (A2A KO) mice, as well as in central nervous system (CNS) cell type-specific (conditional) A2AR knockout (cKO) mice that lack the receptor either in postnatal forebrain neurons or in astrocytes. In WT and in heterozygous A2AR KO mice caffeine pretreatment (25mg/kgip) significantly attenuated MPTP-induced depletion of striatal dopamine. By contrast in homozygous A2AR global KO mice caffeine had no effect on MPTP toxicity. In forebrain neuron A2AR cKO mice, caffeine lost its locomotor stimulant effect, whereas its neuroprotective effect was mostly preserved. In astrocytic A2AR cKO mice, both caffeine's locomotor stimulant and protective properties were undiminished. Taken together, these results indicate that neuroprotection by caffeine in the MPTP model of PD relies on the A2AR, although the specific cellular localization of these receptors remains to be determined. Copyright © 2016 IBRO. All rights reserved.

  20. Targeted deletion of the ileal bile acid transporter eliminates enterohepatic cycling of bile acids in mice.

    PubMed

    Dawson, Paul A; Haywood, Jamie; Craddock, Ann L; Wilson, Martha; Tietjen, Mary; Kluckman, Kimberly; Maeda, Nobuyo; Parks, John S

    2003-09-05

    The ileal apical sodium bile acid cotransporter participates in the enterohepatic circulation of bile acids. In patients with primary bile acid malabsorption, mutations in the ileal bile acid transporter gene (Slc10a2) lead to congenital diarrhea, steatorrhea, and reduced plasma cholesterol levels. To elucidate the quantitative role of Slc10a2 in intestinal bile acid absorption, the Slc10a2 gene was disrupted by homologous recombination in mice. Animals heterozygous (Slc10a2+/-) and homozygous (Slc10a2-/-) for this mutation were physically indistinguishable from wild type mice. In the Slc10a2-/- mice, fecal bile acid excretion was elevated 10- to 20-fold and was not further increased by feeding a bile acid binding resin. Despite increased bile acid synthesis, the bile acid pool size was decreased by 80% and selectively enriched in cholic acid in the Slc10a2-/- mice. On a low fat diet, the Slc10a2-/- mice did not have steatorrhea. Fecal neutral sterol excretion was increased only 3-fold, and intestinal cholesterol absorption was reduced only 20%, indicating that the smaller cholic acid-enriched bile acid pool was sufficient to facilitate intestinal lipid absorption. Liver cholesteryl ester content was reduced by 50% in Slc10a2-/- mice, and unexpectedly plasma high density lipoprotein cholesterol levels were slightly elevated. These data indicate that Slc10a2 is essential for efficient intestinal absorption of bile acids and that alternative absorptive mechanisms are unable to compensate for loss of Slc10a2 function.

  1. Distinct mechanisms are responsible for osteopenia and growth retardation in OASIS-deficient mice.

    PubMed

    Murakami, Tomohiko; Hino, Shin-Ichiro; Nishimura, Riko; Yoneda, Toshiyuki; Wanaka, Akio; Imaizumi, Kazunori

    2011-03-01

    Old astrocyte specifically induced substance (OASIS), which is a new type of endoplasmic reticulum (ER) stress transducer, is a basic leucine zipper transcription factor of the CREB/ATF family that contains a transmembrane domain and is processed by regulated intramembrane proteolysis in response to ER stress. OASIS is selectively expressed in certain types of cells such as astrocytes and osteoblasts. We have previously demonstrated that OASIS activates transcription of the type I collagen gene Col1a1 and contributes to the secretion of bone matrix proteins in osteoblasts, and that OASIS-/- mice exhibit osteopenia and growth retardation. In the present study, we examined whether osteopenia in OASIS-/- mice is rescued by OASIS introduction into osteoblasts. We generated OASIS-/- mice that specifically expressed OASIS in osteoblasts using a 2.3-kb osteoblast-specific type I collagen promoter (OASIS-/-;Tg mice). Histological analysis of OASIS-/-;Tg mice revealed that osteopenia in OASIS-/- mice was rescued by osteoblast-specific expression of the OASIS transgene. The decreased expression levels of type I collagen mRNAs in the bone tissues of OASIS-/- mice were recovered by the OASIS transgene accompanied by the rescue of an abnormal expansion of the rough ER in OASIS-/- osteoblasts. In contrast, growth retardation in OASIS-/- mice did not improve in OASIS-/-;Tg mice. Interestingly, the serum levels of growth hormone (GH) and insulin-like growth factor (IGF)-1 were downregulated in OASIS-/- mice compared with those in wild-type mice. These decreased GH and IGF-1 levels in OASIS-/- mice did not change when OASIS was introduced into osteoblasts. Taken together, these results indicate that OASIS regulates skeletal development by osteoblast-dependent and -independent mechanisms. Copyright © 2010 Elsevier Inc. All rights reserved.

  2. Activation of A2aR attenuates bleomycin-induced pulmonary fibrosis via the SDF-1/CXCR4 axis-related pathway.

    PubMed

    Chen, Yanfan; Yu, Xiaoming; He, Yicheng; Zhang, Lin; Huang, Xiaoying; Xu, Xiaomei; Chen, Mayun; Chen, Xiang; Wang, Liangxing

    2017-01-01

    Previous studies in our lab have demonstrated that Adenosine A2a receptor (A 2a R) gene-knockout mice were vulnerable to pulmonary fibrosis induced by bleomycin (BLM). Inhibition of the SDF-1/CXCR4 axis has been reported to protect the lungs from fibrogenesis in BLM-exposed mice. Little is yet known about the relationships between A 2a R and the SDF-1/CXCR4 axis in idiopathic pulmonary fibrosis (IPF). This study probes the role of A 2a R in the fibrotic process and explores the relationship between A 2a R and the SDF-1/CXCR4 axis in BLM-induced pulmonary fibrosis in mice. In the study, A 2a R-/- and A 2a R+/+ BALB/c mice were exposed to BLM by intratracheal instillation, and CGS-21680 (CGS), an A 2a R agonist, was administered daily for 28 days to the A 2a R+/+ mice in the BLM-induced fibrosis group. Activation of A 2a R produced an anti-fibrotic effect as indicated by the evaluations of the lung architecture, microstructure and ultrastructure. The quantitative analysis indicated that treatment with CGS significantly reduced the collagen content in lungs. To explore the potential mechanisms, the expression levels of A 2a R, SDF-1, and CXCR4 were subsequently determined using ELISA, in situ hybridization (ISH), immunohistochemical staining and western blotting techniques. Administration of CGS markedly suppressed the elevated expression levels of SDF-1 and CXCR4. Moreover, the A 2a R-/- mice developed more severe pulmonary fibrosis than the normal mice when exposed to BLM. Furthermore, the SDF-1/CXCR4 axis was aberrantly uninhibited in the knockout mice. Together, these findings indicated that A 2a R alleviated BLM-induced lung fibrosis, at least partially via the SDF-1/CXCR4 pathway, which could be a potential therapeutic target for the treatment of IPF.

  3. Immunocompetent mouse model of breast cancer for preclinical testing of EphA2-targeted therapy.

    PubMed

    Noblitt, Loren W; Bangari, Dinesh S; Shukla, Shruti; Mohammed, Sulma; Mittal, Suresh K

    2005-01-01

    EphA2, a receptor tyrosine kinase, is elevated in many invasive human breast cancers, and the majority of EphA2 remains unphosphorylated. The successful attachment of ligand EphrinA1 present on the surface of adjacent cells to EphA2 initiates EphA2 phosphorylation leading to its turnover. In vivo efficacy of various approaches targeting EphA2 for breast cancer therapy is usually evaluated in nude mice bearing human breast cancer xenografts. In order to establish an immunocompetent mouse model of breast cancer for EphA2-targeted therapies, we evaluated a mouse breast cancer cell line (MT1A2) for EphA2 expression and phosphorylation. Overexpression of EphA2 was observed in MT1A2 cells and the majority of it remained unphosphorylated signifying that EphA2 in MT1A2 cells behaved similar to that of human breast cancer cells. Human adenovirus subtype 5 (HAd5) vectors expressing secretory forms of EphrinA1 were used for in vitro and in vivo targeting of MT1A2-derived EphA2. MT1A2 cells infected with HAd-EphrinA1-Fc (HAd expressing extracellular domain of human EphrinA1 attached to Fc portion of human IgG1 heavy chain) induced EphA2 activation and its turnover. This led to inhibition in MT1A2 cell colony formation in soft agar and cell viability in monolayer culture. In addition, MT1A2 cells-infected with HAd-EphrinA1-Fc failed to form tumors in syngeneic FVB/n mice at least 32 days postinoculation. Moreover, intratumoral inoculation of FVB/n mice-bearing MT1A2-induced tumors with HAd-EphrinA1-Fc slowed the tumor growth and also resulted in the development of vector-specific immune response. These results indicate that FVB/n mice-bearing MT1A2-induced tumors could serve as an immunocompetent model of breast cancer for EphA2-targeted therapeutic strategies.

  4. Palatable Meal Anticipation in Mice

    PubMed Central

    Hsu, Cynthia T.; Patton, Danica F.; Mistlberger, Ralph E.; Steele, Andrew D.

    2010-01-01

    The ability to sense time and anticipate events is a critical skill in nature. Most efforts to understand the neural and molecular mechanisms of anticipatory behavior in rodents rely on daily restricted food access, which induces a robust increase of locomotor activity in anticipation of daily meal time. Interestingly, rats also show increased activity in anticipation of a daily palatable meal even when they have an ample food supply, suggesting a role for brain reward systems in anticipatory behavior, and providing an alternate model by which to study the neurobiology of anticipation in species, such as mice, that are less well adapted to “stuff and starve” feeding schedules. To extend this model to mice, and exploit molecular genetic resources available for that species, we tested the ability of wild-type mice to anticipate a daily palatable meal. We observed that mice with free access to regular chow and limited access to highly palatable snacks of chocolate or “Fruit Crunchies” avidly consumed the snack but did not show anticipatory locomotor activity as measured by running wheels or video-based behavioral analysis. However, male mice receiving a snack of high fat chow did show increased food bin entry prior to access time and a modest increase in activity in the two hours preceding the scheduled meal. Interestingly, female mice did not show anticipation of a daily high fat meal but did show increased activity at scheduled mealtime when that meal was withdrawn. These results indicate that anticipation of a scheduled food reward in mice is behavior, diet, and gender specific. PMID:20941366

  5. Elevated plus maze for mice.

    PubMed

    Komada, Munekazu; Takao, Keizo; Miyakawa, Tsuyoshi

    2008-12-22

    Although the mouse genome is now completely sequenced, the functions of most of the genes expressed in the brain are not known. The influence of a given gene on a specific behavior can be determined by behavioral analysis of mutant mice. If a target gene is expressed in the brain, behavioral phenotype of the mutant mice could elucidate the genetic mechanism of normal behaviors. The elevated plus maze test is one of the most widely used tests for measuring anxiety-like behavior. The test is based on the natural aversion of mice for open and elevated areas, as well as on their natural spontaneous exploratory behavior in novel environments. The apparatus consists of open arms and closed arms, crossed in the middle perpendicularly to each other, and a center area. Mice are given access to all of the arms and are allowed to move freely between them. The number of entries into the open arms and the time spent in the open arms are used as indices of open space-induced anxiety in mice. Unfortunately, the procedural differences that exist between laboratories make it difficult to duplicate and compare results among laboratories. Here, we present a detailed movie demonstrating our protocol for the elevated plus maze test. In our laboratory, we have assessed more than 90 strains of mutant mice using the protocol shown in the movie. These data will be disclosed as a part of a public database that we are now constructing. Visualization of the protocol will promote better understanding of the details of the entire experimental procedure, allowing for standardization of the protocols used in different laboratories and comparisons of the behavioral phenotypes of various strains of mutant mice assessed using this test.

  6. Forkhead box a2 (FOXA2) is essential for uterine function and fertility.

    PubMed

    Kelleher, Andrew M; Peng, Wang; Pru, James K; Pru, Cindy A; DeMayo, Francesco J; Spencer, Thomas E

    2017-02-07

    Establishment of pregnancy is a critical event, and failure of embryo implantation and stromal decidualization in the uterus contribute to significant numbers of pregnancy losses in women. Glands of the uterus are essential for establishment of pregnancy in mice and likely in humans. Forkhead box a2 (FOXA2) is a transcription factor expressed specifically in the glands of the uterus and is a critical regulator of postnatal uterine gland differentiation in mice. In this study, we conditionally deleted FOXA2 in the adult mouse uterus using the lactotransferrin Cre (Ltf-Cre) model and in the neonatal mouse uterus using the progesterone receptor Cre (Pgr-Cre) model. The uteri of adult FOXA2-deleted mice were morphologically normal and contained glands, whereas the uteri of neonatal FOXA2-deleted mice were completely aglandular. Notably, adult FOXA2-deleted mice are completely infertile because of defects in blastocyst implantation and stromal cell decidualization. Leukemia inhibitory factor (LIF), a critical implantation factor of uterine gland origin, was not expressed during early pregnancy in adult FOXA2-deleted mice. Intriguingly, i.p. injections of LIF initiated blastocyst implantation in the uteri of both gland-containing and glandless adult FOXA2-deleted mice. Although pregnancy was rescued by LIF and was maintained to term in uterine gland-containing adult FOXA2-deleted mice, pregnancy failed by day 10 in neonatal FOXA2-deleted mice lacking uterine glands. These studies reveal a previously unrecognized role for FOXA2 in regulation of adult uterine function and fertility and provide original evidence that uterine glands and, by inference, their secretions play important roles in blastocyst implantation and stromal cell decidualization.

  7. Forkhead box a2 (FOXA2) is essential for uterine function and fertility

    PubMed Central

    Kelleher, Andrew M.; Peng, Wang; Pru, James K.; Pru, Cindy A.; DeMayo, Francesco J.; Spencer, Thomas E.

    2017-01-01

    Establishment of pregnancy is a critical event, and failure of embryo implantation and stromal decidualization in the uterus contribute to significant numbers of pregnancy losses in women. Glands of the uterus are essential for establishment of pregnancy in mice and likely in humans. Forkhead box a2 (FOXA2) is a transcription factor expressed specifically in the glands of the uterus and is a critical regulator of postnatal uterine gland differentiation in mice. In this study, we conditionally deleted FOXA2 in the adult mouse uterus using the lactotransferrin Cre (Ltf-Cre) model and in the neonatal mouse uterus using the progesterone receptor Cre (Pgr-Cre) model. The uteri of adult FOXA2-deleted mice were morphologically normal and contained glands, whereas the uteri of neonatal FOXA2-deleted mice were completely aglandular. Notably, adult FOXA2-deleted mice are completely infertile because of defects in blastocyst implantation and stromal cell decidualization. Leukemia inhibitory factor (LIF), a critical implantation factor of uterine gland origin, was not expressed during early pregnancy in adult FOXA2-deleted mice. Intriguingly, i.p. injections of LIF initiated blastocyst implantation in the uteri of both gland-containing and glandless adult FOXA2-deleted mice. Although pregnancy was rescued by LIF and was maintained to term in uterine gland-containing adult FOXA2-deleted mice, pregnancy failed by day 10 in neonatal FOXA2-deleted mice lacking uterine glands. These studies reveal a previously unrecognized role for FOXA2 in regulation of adult uterine function and fertility and provide original evidence that uterine glands and, by inference, their secretions play important roles in blastocyst implantation and stromal cell decidualization. PMID:28049832

  8. Adenosine transporter ENT1 regulates the acquisition of goal-directed behavior and ethanol drinking through A2A receptor in the dorsomedial striatum.

    PubMed

    Nam, Hyung Wook; Hinton, David J; Kang, Na Young; Kim, Taehyun; Lee, Moonnoh R; Oliveros, Alfredo; Adams, Chelsea; Ruby, Christina L; Choi, Doo-Sup

    2013-03-06

    Adenosine signaling has been implicated in the pathophysiology of many psychiatric disorders including alcoholism. Striatal adenosine A2A receptors (A2AR) play an essential role in both ethanol drinking and the shift from goal-directed action to habitual behavior. However, direct evidence for a role of striatal A2AR signaling in ethanol drinking and habit development has not been established. In the present study, we found that decreased A2AR-mediated CREB activity in the dorsomedial striatum (DMS) enhanced initial behavioral acquisition of goal-directed behaviors and the vulnerability to progress to excessive ethanol drinking during operant conditioning in mice lacking ethanol-sensitive adenosine transporter ENT1 (ENT1(-/-)). Using mice expressing β-galactosidase (lacZ) under the control of seven repeated CRE sites in both genotypes (CRE-lacZ/ENT1(+/+) mice and CRE-lacZ/ENT1(-/-) mice) and the dominant-negative form of CREB, we found that reduced CREB activity in the DMS was causally associated with decreased A2AR signaling and increased goal-directed ethanol drinking. Finally, we have demonstrated that the A2AR antagonist ZM241385 dampened protein kinase A activity-mediated signaling in the DMS and promoted excessive ethanol drinking in ENT1(+/+) mice, but not in ENT1(-/-) mice. Our results indicate that A2AR-mediated CREB signaling in the DMS is a key determinant in enhancing the development of goal-directed ethanol drinking in mice.

  9. Adenosine through the A2A adenosine receptor increases IL-1β in the brain contributing to anxiety.

    PubMed

    Chiu, Gabriel S; Darmody, Patrick T; Walsh, John P; Moon, Morgan L; Kwakwa, Kristin A; Bray, Julie K; McCusker, Robert H; Freund, Gregory G

    2014-10-01

    Anxiety is one of the most commonly reported psychiatric conditions, but its pathogenesis is poorly understood. Ailments associated with activation of the innate immune system, however, are increasingly linked to anxiety disorders. In adult male mice, we found that adenosine doubled caspase-1 activity in brain by a pathway reliant on ATP-sensitive potassium (KATP) channels, protein kinase A (PKA) and the A2A adenosine receptor (AR). In addition, adenosine-dependent activation of caspase-1 increased interleukin (IL)-1β in the brain by 2-fold. Peripheral administration of adenosine in wild-type (WT) mice led to a 2.3-fold increase in caspase-1 activity in the amygdala and to a 33% and 42% reduction in spontaneous locomotor activity and food intake, respectively, that were not observed in caspase-1 knockout (KO), IL-1 receptor type 1 (IL-1R1) KO and A2A AR KO mice or in mice administered a caspase-1 inhibitor centrally. Finally, adenosine administration increased anxiety-like behaviors in WT mice by 28% in the open field test and by 55% in the elevated zero-maze. Caspase-1 KO mice, IL-1R1 KO mice, A2A AR KO mice and WT mice treated with the KATP channel blocker, glyburide, were resistant to adenosine-induced anxiety-like behaviors. Thus, our results indicate that adenosine can act as an anxiogenic by activating caspase-1 and increasing IL-1β in the brain. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Magnetic eye tracking in mice.

    PubMed

    Payne, Hannah L; Raymond, Jennifer L

    2017-09-05

    Eye movements provide insights about a wide range of brain functions, from sensorimotor integration to cognition; hence, the measurement of eye movements is an important tool in neuroscience research. We describe a method, based on magnetic sensing, for measuring eye movements in head-fixed and freely moving mice. A small magnet was surgically implanted on the eye, and changes in the magnet angle as the eye rotated were detected by a magnetic field sensor. Systematic testing demonstrated high resolution measurements of eye position of <0.1°. Magnetic eye tracking offers several advantages over the well-established eye coil and video-oculography methods. Most notably, it provides the first method for reliable, high-resolution measurement of eye movements in freely moving mice, revealing increased eye movements and altered binocular coordination compared to head-fixed mice. Overall, magnetic eye tracking provides a lightweight, inexpensive, easily implemented, and high-resolution method suitable for a wide range of applications.

  11. Dnmt3a2: a hub for enhancing cognitive functions.

    PubMed

    Oliveira, A M M; Hemstedt, T J; Freitag, H E; Bading, H

    2016-08-01

    The mechanisms responsible for fear memory formation and extinction are far from being understood. Uncovering the molecules and mechanisms regulating these processes is vital for identifying molecular targets for the development of novel therapeutic strategies for anxiety and fear disorders. Cognitive abilities require the activation of gene expression necessary to the consolidation of lasting changes in neuronal function. In this study we established a key role for an epigenetic factor, the de novo DNA methyltransferase, Dnmt3a2, in memory formation and extinction. We found that Dnmt3a2 overexpression in the hippocampus of young adult mice induced memory enhancements in a variety of situations; it converted a weak learning experience into long-term memory, enhanced fear memory formation and facilitated fear memory extinction. Dnmt3a2 overexpression was also associated with the increased expression of plasticity-related genes. Furthermore, the knockdown of Dnmt3a2 expression impaired the animals' ability to extinguish memories, identifying Dnmt3a2 as a key player in extinction. Thus, Dnmt3a2 is at the core of memory processes and represents a novel target for cognition-enhancing therapies to ameliorate anxiety and fear disorders and boost memory consolidation.

  12. Peritoneal inflammation and fibrosis in C-reactive protein transgenic mice undergoing peritoneal dialysis solution treatment.

    PubMed

    Poon, Peter Yam-Kau; Lan, Hui-Yao; Kwan, Bonnie Ching-Ha; Huang, Xiao-Ru; Chow, Kai-Ming; Szeto, Cheuk-Chun; Li, Philip Kam-Tao

    2017-02-01

    C-reactive protein (CRP) is a mediator of systemic inflammation. Peritoneal dialysis (PD) is known to cause peritoneal inflammation and fibrosis. We compare the degree of peritoneal inflammation and fibrosis in wild-type (WT) and CRP-transgenic (Tg) mice after PD treatment. WT (n = 7) and CRP-Tg (n = 10) C57BL/6 J mice (all male, 10-12 weeks old) were injected intra-peritoneally with 4.25% dextrose PD solution (3 mL/mouse) daily for 28 days, followed by a 2-h peritoneal equilibration test (PET). The mice were then killed. Parietal peritoneal and omental tissues were collected for the assessment of inflammation and fibrosis. After 28 days of PD treatment, CRP-Tg mice had higher dialysate-to-plasma (D/P) creatinine ratio than that of WT mice. Parietal peritoneum of the CRP-Tg mice was more cellular and thicker than that of the WT mice. CRP-Tg mice also had higher connective tissue growth factor (CTGF), intercellular adhesion molecule 1 (ICAM1) and tumor necrosis factor α (TNFα) RNA expressions as well as immunohistochemical staining in the parietal peritoneum than that of the WT mice. CRP-Tg mice have significantly more inflammation and fibrosis than WT mice after PD treatment. Our results suggest that CRP play a role in inflammation and fibrosis induced by PD. The implication of our results to human PD therapy needs further investigations. © 2016 Asian Pacific Society of Nephrology.

  13. Unique nuclear vacuoles in the motor neurons of conditional ADAR2-knockout mice.

    PubMed

    Sasaki, Shoichi; Takenari Yamashita; Hideyama, Takuto; Kwak, Shin

    2014-03-06

    A reduction in adenosine deaminase acting on RNA 2 (ADAR2) activity causes the death of spinal motor neurons specifically via the GluA2 Q/R site-RNA editing failure in sporadic amyotrophic lateral sclerosis (ALS). We studied, over time, the spinal cords of ADAR2-knockout mice, which are the mechanistic model mice for sporadic ALS, using homozygous ADAR2(flox/flox)/VAChT-Cre.Fast (AR2), homozygous ADAR2(flox/flox)/VAChT-Cre.Slow (AR2Slow), and heterozygous ADAR2(flox/+)/VAChT-Cre.Fast (AR2H) mice. The conditional ADAR2-knockout mice were divided into 3 groups by stage: presymptomatic (AR2H mice), early symptomatic (AR2 mice, AR2H mice) and late symptomatic (AR2Slow mice). Light-microscopically, some motor neurons in AR2 and AR2H mice (presymptomatic) showed simple neuronal atrophy and astrogliosis, and AR2H (early symptomatic) and AR2Slow mice often showed vacuoles predominantly in motor neurons. The number of vacuole-bearing anterior horn neurons decreased with the loss of anterior horn neurons in AR2H mice after 40 weeks of age. Electron-microscopically, in AR2 mice, while the cytoplasm of normal-looking motor neurons was almost always normal-appearing, the interior of dendrites was frequently loose and disorganized. In AR2H and AR2Slow mice, large vacuoles without a limiting membrane were observed in the anterior horns, preferentially in the nuclei of motor neurons, astrocytes and oligodendrocytes. Nuclear vacuoles were not observed in AR2res (ADAR2(flox/flox)/VAChT-Cre.Fast/GluR-B(R/R)) mice, in which motor neurons express edited GluA2 in the absence of ADAR2. These findings suggest that ADAR2-reduction is associated with progressive deterioration of nuclear architecture, resulting in vacuolated nuclei due to a Ca(2+)-permeable AMPA receptor-mediated mechanism. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. EphA2 Is a Therapy Target in EphA2-Positive Leukemias but Is Not Essential for Normal Hematopoiesis or Leukemia.

    PubMed

    Charmsaz, Sara; Beckett, Kirrilee; Smith, Fiona M; Bruedigam, Claudia; Moore, Andrew S; Al-Ejeh, Fares; Lane, Steven W; Boyd, Andrew W

    2015-01-01

    Members of the Eph family of receptor tyrosine kinases and their membrane bound ephrin ligands have been shown to play critical roles in many developmental processes and more recently have been implicated in both normal and pathological processes in post-embryonic tissues. In particular, expression studies of Eph receptors and limited functional studies have demonstrated a role for the Eph/ephrin system in hematopoiesis and leukemogenesis. In particular, EphA2 was reported on hematopoietic stem cells and stromal cells. There are also reports of EphA2 expression in many different types of malignancies including leukemia, however there is a lack of knowledge in understanding the role of EphA2 in hematopoiesis and leukemogenesis. We explored the role of EphA2 in hematopoiesis by analyzing wild type and EphA2 knockout mice. Mature, differentiated cells, progenitors and hematopoietic stem cells derived from knockout and control mice were analyzed and no significant abnormality was detected. These studies showed that EphA2 does not have an obligatory role in normal hematopoiesis. Comparative studies using EphA2-negative MLL-AF9 leukemias derived from EphA2-knockout animals showed that there was no detectable functional role for EphA2 in the initiation or progression of the leukemic process. However, expression of EphA2 in leukemias initiated by MLL-AF9 suggested that this protein might be a possible therapy target in this type of leukemia. We showed that treatment with EphA2 monoclonal antibody IF7 alone had no effect on tumorigenicity and latency of the MLL-AF9 leukemias, while targeting of EphA2 using EphA2 monoclonal antibody with a radioactive payload significantly impaired the leukemic process. Altogether, these results identify EphA2 as a potential radio-therapeutic target in leukemias with MLL translocation.

  15. EphA2 Is a Therapy Target in EphA2-Positive Leukemias but Is Not Essential for Normal Hematopoiesis or Leukemia

    PubMed Central

    Charmsaz, Sara; Beckett, Kirrilee; Smith, Fiona M.; Bruedigam, Claudia; Moore, Andrew S.; Al-Ejeh, Fares; Lane, Steven W.; Boyd, Andrew W.

    2015-01-01

    Members of the Eph family of receptor tyrosine kinases and their membrane bound ephrin ligands have been shown to play critical roles in many developmental processes and more recently have been implicated in both normal and pathological processes in post-embryonic tissues. In particular, expression studies of Eph receptors and limited functional studies have demonstrated a role for the Eph/ephrin system in hematopoiesis and leukemogenesis. In particular, EphA2 was reported on hematopoietic stem cells and stromal cells. There are also reports of EphA2 expression in many different types of malignancies including leukemia, however there is a lack of knowledge in understanding the role of EphA2 in hematopoiesis and leukemogenesis. We explored the role of EphA2 in hematopoiesis by analyzing wild type and EphA2 knockout mice. Mature, differentiated cells, progenitors and hematopoietic stem cells derived from knockout and control mice were analyzed and no significant abnormality was detected. These studies showed that EphA2 does not have an obligatory role in normal hematopoiesis. Comparative studies using EphA2-negative MLL-AF9 leukemias derived from EphA2-knockout animals showed that there was no detectable functional role for EphA2 in the initiation or progression of the leukemic process. However, expression of EphA2 in leukemias initiated by MLL-AF9 suggested that this protein might be a possible therapy target in this type of leukemia. We showed that treatment with EphA2 monoclonal antibody IF7 alone had no effect on tumorigenicity and latency of the MLL-AF9 leukemias, while targeting of EphA2 using EphA2 monoclonal antibody with a radioactive payload significantly impaired the leukemic process. Altogether, these results identify EphA2 as a potential radio-therapeutic target in leukemias with MLL translocation. PMID:26083390

  16. BDNF-Deficient Mice Show Reduced Psychosis-Related Behaviors Following Chronic Methamphetamine.

    PubMed

    Manning, Elizabeth E; Halberstadt, Adam L; van den Buuse, Maarten

    2016-04-01

    One of the most devastating consequences of methamphetamine abuse is increased risk of psychosis. Brain-derived neurotrophic factor has been implicated in both psychosis and neuronal responses to methamphetamine. We therefore examined persistent psychosis-like behavioral effects of methamphetamine in brain-derived neurotrophic factor heterozygous mice. Mice were chronically treated with methamphetamine from 6 to 9 weeks of age, and locomotor hyperactivity to an acute D-amphetamine challenge was tested in photocell cages after a 2-week withdrawal period. Methamphetamine-treated wild-type mice, but not brain-derived neurotrophic factor heterozygous mice, showed locomotor sensitization to acute 3mg/kg D-amphetamine. Qualitative analysis of exploration revealed tolerance to D-amphetamine effects on entropy in methamphetamine-treated brain-derived neurotrophic factor heterozygous mice, but not wild-type mice. Chronic methamphetamine exposure induces contrasting profiles of behavioral changes in wild-type and brain-derived neurotrophic factor heterozygous mice, with attenuation of behaviors relevant to psychosis in methamphetamine-treated brain-derived neurotrophic factor heterozygous mice. This suggests that brain-derived neurotrophic factor signalling changes may contribute to development of psychosis in methamphetamine users. © The Author 2015. Published by Oxford University Press on behalf of CINP.

  17. Changes in emotional behavior of mice in the hole-board test after olfactory bulbectomy.

    PubMed

    Saitoh, Akiyoshi; Hirose, Noritaka; Yamada, Mitsuhiko; Yamada, Misa; Nozaki, Chihiro; Oka, Takuma; Kamei, Junzo

    2006-12-01

    The most consistent behavioral change caused by olfactory bulbectomy (OBX) is a hyperemotional response to novel environmental stimuli. The aim of this study was to characterize the emotional behavior of OBX mice using the hole-board test. After the olfactory bulbs were lesioned, sham and OBX mice were housed in single cages for 14 days. The number of head-dips in the hole-board test in single-housed OBX mice was significantly greater than that in single-housed sham mice. The head-dipping behaviors in single-housed sham and OBX mice were reversed by treatment with diazepam, a typical benzodiazepine anxiolytic. (+/-)-8-Hydroxy-2-(di-n-propylamino) tetraline hydrobromide (8-OH-DPAT), a selective 5-HT(1A)-receptor agonist that has a non-benzodiazepine anxiolytic-like effect, and (+)-4-[(aR)-a-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethyl benzamide (SNC80), a delta-opioid-receptor agonist, also significantly reversed the number of head-dips in single-housed sham and OBX mice. In conclusion, we suggest that the single-housed OBX mice showed heightened emotional behavior (e.g., increase in head-dipping behavior) in the hole-board test. In addition, we suggest that the hyperemotional behavior characterized by head-dipping behavior in OBX mice was selectively reversed by benzodiazepine and non-benzodiazepine anxiolytics.

  18. Hepatic response to oxidative injury in long-lived Ames dwarf mice

    PubMed Central

    Sun, Liou Y.; Bokov, Alex F.; Richardson, Arlan; Miller, Richard A.

    2011-01-01

    Multiple stress resistance pathways were evaluated in the liver of Ames dwarf mice before and after exposure to the oxidative toxin diquat, seeking clues to the exceptional longevity conferred by this mutation. Before diquat treatment, Ames dwarf mice, compared with nonmutant littermate controls, had 2- to 6-fold higher levels of expression of mRNAs for immediate early genes and 2- to 5-fold higher levels of mRNAs for genes dependent on the transcription factor Nrf2. Diquat led to a 2-fold increase in phosphorylation of the stress kinase ERK in control (but not Ames dwarf) mice and to a 50% increase in phosphorylation of the kinase JNK2 in Ames dwarf (but not control) mice. Diquat induction of Nrf2 protein was higher in dwarf mice than in controls. Of 6 Nrf2-responsive genes evaluated, 4 (HMOX, NQO-1, MT-1, and MT-2) remained 2- to 10-fold lower in control than in dwarf liver after diquat, and the other 2 (GCLM and TXNRD) reached levels already seen in dwarf liver at baseline. Thus, livers of Ames dwarf mice differ systematically from controls in multiple stress resistance pathways before and after exposure to diquat, suggesting mechanisms for stress resistance and extended longevity in Ames dwarf mice.—Sun, L. Y., Bokov, A. F., Richardson, A., Miller, R. A. Hepatic response to oxidative injury in long-lived Ames dwarf mice. PMID:20826540

  19. Lack of susceptibility of transgenic mice carrying the human c-Ha-ras proto-oncogene (rasH2 mice) to phenolphthalein in a 6-month carcinogenicity study.

    PubMed

    Koujitani, T; Yasuhara, K; Usui, T; Nomura, T; Onodera, H; Takagi, H; Hirose, M; Mitsumori, K

    2000-05-01

    Phenolphthalein has carcinogenic activity, causing malignant lymphomas in B6C3F1 mice at a dietary dose of 3000 ppm in a 2-year carcinogenicity study and in heterozygous p53-deficient female mice at the same dose in a 6-month study. To examine whether phenolphthalein carcinogenic potential can be detected in male and female transgenic (Tg) mice carrying the human c-Ha-ras gene (rasH2 mice) and their wild-type littermates (non-Tg mice), a diet containing 3000, 6000 or 12000 ppm was given for 6 months. Unequivocal induction of neoplastic lesions was not apparent, suggesting that rasH2 mice are resistant to the induction of malignant lymphomas by the treatment of phenolphthalein.

  20. Ephrin-A2 reverse signaling negatively regulates neural progenitor proliferation and neurogenesis

    PubMed Central

    Holmberg, Johan; Armulik, Annika; Senti, Kirsten-André; Edoff, Karin; Spalding, Kirsty; Momma, Stefan; Cassidy, Rob; Flanagan, John G.; Frisén, Jonas

    2005-01-01

    The number of cells in an organ is regulated by mitogens and trophic factors that impinge on intrinsic determinants of proliferation and apoptosis. We here report the identification of an additional mechanism to control cell number in the brain: EphA7 induces ephrin-A2 reverse signaling, which negatively regulates neural progenitor cell proliferation. Cells in the neural stem cell niche in the adult brain proliferate more and have a shorter cell cycle in mice lacking ephrin-A2. The increased progenitor proliferation is accompanied by a higher number of cells in the olfactory bulb. Disrupting the interaction between ephrin-A2 and EphA7 in the adult brain of wild-type mice disinhibits proliferation and results in increased neurogenesis. The identification of ephrin-A2 and EphA7 as negative regulators of progenitor cell proliferation reveals a novel mechanism to control cell numbers in the brain. PMID:15713841

  1. Ephrin-A2 reverse signaling negatively regulates neural progenitor proliferation and neurogenesis.

    PubMed

    Holmberg, Johan; Armulik, Annika; Senti, Kirsten-André; Edoff, Karin; Spalding, Kirsty; Momma, Stefan; Cassidy, Rob; Flanagan, John G; Frisén, Jonas

    2005-02-15

    The number of cells in an organ is regulated by mitogens and trophic factors that impinge on intrinsic determinants of proliferation and apoptosis. We here report the identification of an additional mechanism to control cell number in the brain: EphA7 induces ephrin-A2 reverse signaling, which negatively regulates neural progenitor cell proliferation. Cells in the neural stem cell niche in the adult brain proliferate more and have a shorter cell cycle in mice lacking ephrin-A2. The increased progenitor proliferation is accompanied by a higher number of cells in the olfactory bulb. Disrupting the interaction between ephrin-A2 and EphA7 in the adult brain of wild-type mice disinhibits proliferation and results in increased neurogenesis. The identification of ephrin-A2 and EphA7 as negative regulators of progenitor cell proliferation reveals a novel mechanism to control cell numbers in the brain.

  2. Lack of susceptibility of heterozygous p53-knockout CBA and CIEA mice to phenolphthalein in a 6-month carcinogenicity study.

    PubMed

    Okamura, Miwa; Kashida, Yoko; Watanabe, Takao; Yasuhara, Kazuo; Onodera, Hiroshi; Hirose, Masao; Usui, Toshimi; Tamaoki, Norikazu; Mitsumori, Kunitoshi

    2003-03-14

    Phenolphthalein has carcinogenic activity, causing malignant lymphomas in B6C3F1 mice at a dietary dose of 3000 ppm in a 2-year carcinogenicity study and in female heterozygous p53-knockout TSG mice (C57BL/6 background) at the same dose in a 6-month study. To examine whether carcinogenic potential of phenolphthalein can be detected in other p53-knockout mouse [p53 (+/-)] strains such as p53 (+/-) CBA mice or p53 (+/-) CIEA mice (C57BL/6 background) and their littermates, they were given a diet containing 0, 6000 or 12000 ppm for 6 months. Unequivocal induction of neoplastic lesions was not apparent, suggesting that p53 (+/-) CBA mice and p53 (+/-) CIEA mice are resistant to the induction of malignant lymphomas by the treatment of phenolphthalein.

  3. IgE levels in nude mice.

    PubMed

    Ito, K; Ogita, T; Suko, M; Mori, M; Kudo, K; Hayakawa, T; Okudaira, H; Horiuchi, Y

    1979-01-01

    IgE levels in nude mice were estimated by the one-step single radial radiodiffusion method antisera prepared by immunization of guinea pigs with an IgE-rich fraction obtained from sera of normal mice infected with Nippostrongylus brasiliensis and immunized with DNP-ovalbumin in alum gel. 3 out of 8 nude mice had IgE levels significantly higher than those of normal mice.

  4. Macrophage A2A Adenosinergic Receptor Modulates Oxygen-Induced Augmentation of Murine Lung Injury

    PubMed Central

    D’Alessio, Franco R.; Eto, Yoshiki; Chau, Eric; Avalos, Claudia; Waickman, Adam T.; Garibaldi, Brian T.; Mock, Jason R.; Files, Daniel C.; Sidhaye, Venkataramana; Polotsky, Vsevolod Y.; Powell, Jonathan; Horton, Maureen; King, Landon S.

    2013-01-01

    Acute respiratory distress syndrome (ARDS) causes significant morbidity and mortality. Exacerbating factors increasing the risk of ARDS remain unknown. Supplemental oxygen is often necessary in both mild and severe lung disease. The potential effects of supplemental oxygen may include augmentation of lung inflammation by inhibiting anti-inflammatory pathways in alveolar macrophages. We sought to determine oxygen-derived effects on the anti-inflammatory A2A adenosinergic (ADORA2A) receptor in macrophages, and the role of the ADORA2A receptor in lung injury. Wild-type (WT) and ADORA2A−/− mice received intratracheal lipopolysaccharide (IT LPS), followed 12 hours later by continuous exposure to 21% oxygen (control mice) or 60% oxygen for 1 to 3 days. We measured the phenotypic endpoints of lung injury and the alveolar macrophage inflammatory state. We tested an ADORA2A-specific agonist, CGS-21680 hydrochloride, in LPS plus oxygen-exposed WT and ADORA2A−/− mice. We determined the specific effects of myeloid ADORA2A, using chimera experiments. Compared with WT mice, ADORA2A−/− mice exposed to IT LPS and 60% oxygen demonstrated significantly more histologic lung injury, alveolar neutrophils, and protein. Macrophages from ADORA2A−/− mice exposed to LPS plus oxygen expressed higher concentrations of proinflammatory cytokines and cosignaling molecules. CGS-21680 prevented the oxygen-induced augmentation of lung injury after LPS only in WT mice. Chimera experiments demonstrated that the transfer of WT but not ADORA2A−/− bone marrow cells into irradiated ADORA2A−/− mice reduced lung injury after LPS plus oxygen, demonstrating myeloid ADORA2A protection. ADORA2A is protective against lung injury after LPS and oxygen. Oxygen after LPS increases macrophage activation to augment lung injury by inhibiting the ADORA2A pathway. PMID:23349051

  5. Sodium-Glucose Transporter-2 (SGLT2; SLC5A2) Enhances Cellular Uptake of Aminoglycosides

    PubMed Central

    Jiang, Meiyan; Wang, Qi; Karasawa, Takatoshi; Koo, Ja-Won; Li, Hongzhe; Steyger, Peter S.

    2014-01-01

    Aminoglycoside antibiotics, like gentamicin, continue to be clinically essential worldwide to treat life-threatening bacterial infections. Yet, the ototoxic and nephrotoxic side-effects of these drugs remain serious complications. A major site of gentamicin uptake and toxicity resides within kidney proximal tubules that also heavily express electrogenic sodium-glucose transporter-2 (SGLT2; SLC5A2) in vivo. We hypothesized that SGLT2 traffics gentamicin, and promotes cellular toxicity. We confirmed in vitro expression of SGLT2 in proximal tubule-derived KPT2 cells, and absence in distal tubule-derived KDT3 cells. D-glucose competitively decreased the uptake of 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose (2-NBDG), a fluorescent analog of glucose, and fluorescently-tagged gentamicin (GTTR) by KPT2 cells. Phlorizin, an SGLT2 antagonist, strongly inhibited uptake of 2-NBDG and GTTR by KPT2 cells in a dose- and time-dependent manner. GTTR uptake was elevated in KDT3 cells transfected with SGLT2 (compared to controls); and this enhanced uptake was attenuated by phlorizin. Knock-down of SGLT2 expression by siRNA reduced gentamicin-induced cytotoxicity. In vivo, SGLT2 was robustly expressed in kidney proximal tubule cells of heterozygous, but not null, mice. Phlorizin decreased GTTR uptake by kidney proximal tubule cells in Sglt2+/− mice, but not in Sglt2−/− mice. However, serum GTTR levels were elevated in Sglt2−/− mice compared to Sglt2+/− mice, and in phlorizin-treated Sglt2+/− mice compared to vehicle-treated Sglt2+/− mice. Loss of SGLT2 function by antagonism or by gene deletion did not affect gentamicin cochlear loading or auditory function. Phlorizin did not protect wild-type mice from kanamycin-induced ototoxicity. We conclude that SGLT2 can traffic gentamicin and contribute to gentamicin-induced cytotoxicity. PMID:25268124

  6. LUNAR SAMPLES - APOLLO 11 (MICE)

    NASA Image and Video Library

    1969-08-05

    S69-40940 (August 1969) --- Landrum Young (seated), Brown and Root - Northrop, and Russell Stullken, Manned Spacecraft Center (MSC), examine mice in the Animal Laboratory which have been inoculated with lunar sample material. The sample material was collected by astronauts Neil A. Armstrong and Edwin E. Aldrin Jr. during their lunar surface extravehicular activity (EVA) on July 20, 1969.

  7. β-Adrenergic Receptor Mediation of Stress-Induced Reinstatement of Extinguished Cocaine-Induced Conditioned Place Preference in Mice: Roles for β1 and β2 Adrenergic Receptors

    PubMed Central

    Vranjkovic, Oliver; Hang, Shona; Baker, David A.

    2012-01-01

    Stress can trigger the relapse of drug use in recovering cocaine addicts and reinstatement in rodent models through mechanisms that may involve norepinephrine release and β-adrenergic receptor activation. The present study examined the role of β-adrenergic receptor subtypes in the stressor-induced reinstatement of extinguished cocaine-induced (15 mg/kg i.p.) conditioned place preference in mice. Forced swim (6 min at 22°C) stress or activation of central noradrenergic neurotransmission by administration of the selective α2 adrenergic receptor antagonist 2-[(4,5-dihydro-1H-imidazol-2-yl)methyl]-2,3-dihydro-1-methyl-1H-isoindole (BRL-44,408) (10 mg/kg i.p.) induced reinstatement in wild-type, but not β- adrenergic receptor-deficient Adrb1/Adrb2 double-knockout, mice. In contrast, cocaine administration (15 mg/kg i.p.) resulted in reinstatement in both wild-type and β-adrenergic receptor knockout mice. Stress-induced reinstatement probably involved β2 adrenergic receptors. The β2 adrenergic receptor antagonist -(isopropylamino)-1-[(7-methyl-4-indanyl)oxy]butan-2-ol (ICI-118,551) (1 or 2 mg/kg i.p.) blocked reinstatement by forced swim or BRL-44,408, whereas administration of the nonselective β-adrenergic receptor agonist isoproterenol (2 or 4 mg/kg i.p.) or the β2 adrenergic receptor-selective agonist clenbuterol (2 or 4 mg/kg i.p.) induced reinstatement. Forced swim-induced, but not BRL-44,408-induced, reinstatement was also blocked by a high (20 mg/kg) but not low (10 mg/kg) dose of the β1 adrenergic receptor antagonist betaxolol, and isoproterenol-induced reinstatement was blocked by pretreatment with either ICI-118,551 or betaxolol, suggesting a potential cooperative role for β1 and β2 adrenergic receptors in stress-induced reinstatement. Overall, these findings suggest that targeting β-adrenergic receptors may represent a promising pharmacotherapeutic strategy for preventing drug relapse, particularly in cocaine addicts whose drug use is stress

  8. Involvement of EphA2 in the formation of the tail notochord via interaction with ephrinA1.

    PubMed

    Naruse-Nakajima, C; Asano, M; Iwakura, Y

    2001-04-01

    Eph receptors have been implicated in cell-to-cell interaction during embryogenesis. We generated EphA2 mutant mice using a gene trap method. Homozygous mutant mice developed short and kinky tails. In situ hybridization using a Brachyury probe found the notochord to be abnormally bifurcated at the caudal end between 11.5 and 12.5 days post coitum. EphA2 was expressed at the tip of the tail notochord, while one of its ligands, ephrinA1, was at the tail bud in normal mice. In contrast, EphA2-deficient notochordal cells were spread broadly into the tail bud. These observations suggest that EphA2 and its ligands are involved in the positioning of the tail notochord through repulsive signals between cells expressing these molecules on the surface.

  9. Fructose- and glucose-conditioned preferences in FVB mice: strain differences in post-oral sugar appetition

    PubMed Central

    Zukerman, Steven; Ackroff, Karen

    2014-01-01

    Recent studies indicate that, unlike glucose, fructose has little or no post-oral preference conditioning actions in C57BL/6J (B6) mice. The present study determined whether this is also the case for FVB mice, which overconsume fructose relative to B6 mice. In experiment 1, FVB mice strongly preferred a noncaloric 0.1% sucralose + 0.1% saccharin (S+S) solution to 8% fructose in a 2-day choice test but switched their preference to fructose after separate experience with the two sweeteners. Other FVB mice displayed a stronger preference for 8% glucose over S+S. In a second experiment, ad libitum-fed FVB mice trained 24 h/day acquired a significant preference for a flavor (CS+) paired with intragastric (IG) self-infusions of 16% fructose over a different flavor (CS−) paired with IG water infusions. IG fructose infusions also conditioned flavor preferences in food-restricted FVB mice trained 1 h/day. IG infusions of 16% glucose conditioned stronger preferences in FVB mice trained 24- or 1 h/day. Thus, fructose has post-oral flavor conditioning effects in FVB mice, but these effects are less pronounced than those produced by glucose. Further studies of the differential post-oral conditioning effects of fructose and glucose in B6 and FVB mice should enhance our understanding of the physiological processes involved in sugar reward. PMID:25320345

  10. HZE Radiation Leukemogenesis in Mice

    NASA Astrophysics Data System (ADS)

    Peng, Yuanlin

    Radiation exposure is a risk factor for acute myeloid leukemia (AML). The Leukemogenesis NSCOR was developed to compare this risk for low LET vs HZE radiations as a means to better assess the leukemia risk to astronauts posed by space radiation. Individual projects within the NSCOR explore HZE radiation leukemogenesis in murine model systems and extend the findings to AML in humans. AML sensitive CBA/CaJ mice have been irradiated with 1 GeV 56 Fe particles at NSRL and with 137 Cs gamma-rays at Colorado State University and followed to 800 days of age for the development of AML. Molecular and cytogenetic analyses of HZE- and gamma-induced AML, including assays for chromosomal aberrations, PU.1 deletion, gene expression, array CGH and microsatellite instability are ongoing. Preliminary data indicate that 56 Fe particles are no more effective in inducing AML or shortening lifespan than gamma-rays. Studies designed to address the individual molecular steps in leukemogenesis and determine the effects of radiation and genetic background on each step have been initiated using knockout mice. Deletion of the PU.1 gene on mouse chromosome 2 is a critical step in this murine model of radiation leukemogenesis. Two of the three HZE-induced AMLs that could be assayed and thirteen of fourteen γ-induced AMLs had PU.1 loss as determined by Fluorescence in Situ Hybridization (FISH). We have found that AML sensitive CBA/CaJ mice have a higher incidence of Chr. 2 deletion in bone marrow cells following 56 Fe irradiation than AML resistant C57BL/6 mice. This study is being extended to proton irradiated mice. Our preliminary results indicate that microsatellite instability may be common in HZE irradiated progenitor cells. To determine if these cytogenetic changes can be induced in human myeloid progenitor cells by gamma, proton or HZE irradiation we are generating NOD/SCID mice that have been "humanized" by being transplanted with human hematopoietic stem cells. We are currently

  11. Transplacental arsenic carcinogenesis in mice

    SciTech Connect

    Waalkes, Michael P.; Liu, Jie; Diwan, Bhalchandra A.

    2007-08-01

    Our work has focused on the carcinogenic effects of in utero arsenic exposure in mice. Our data show that a short period of maternal exposure to inorganic arsenic in the drinking water is an effective, multi-tissue carcinogen in the adult offspring. These studies have been reproduced in three temporally separate studies using two different mouse strains. In these studies pregnant mice were treated with drinking water containing sodium arsenite at up to 85 ppm arsenic from days 8 to 18 of gestation, and the offspring were observed for up to 2 years. The doses used in all these studies weremore » well tolerated by both the dam and offspring. In C3H mice, two separate studies show male offspring exposed to arsenic in utero developed liver carcinoma and adrenal cortical adenoma in a dose-related fashion during adulthood. Prenatally exposed female C3H offspring show dose-related increases in ovarian tumors and lung carcinoma and in proliferative lesions (tumors plus preneoplastic hyperplasia) of the uterus and oviduct. In addition, prenatal arsenic plus postnatal exposure to the tumor promoter, 12-O-tetradecanoyl phorbol-13-acetate (TPA) in C3H mice produces excess lung tumors in both sexes and liver tumors in females. Male CD1 mice treated with arsenic in utero develop tumors of the liver and adrenal and renal hyperplasia while females develop tumors of urogenital system, ovary, uterus and adrenal and hyperplasia of the oviduct. Additional postnatal treatment with diethylstilbestrol or tamoxifen after prenatal arsenic in CD1 mice induces urinary bladder transitional cell proliferative lesions, including carcinoma and papilloma, and enhances the carcinogenic response in the liver of both sexes. Overall this model has provided convincing evidence that arsenic is a transplacental carcinogen in mice with the ability to target tissues of potential human relevance, such as the urinary bladder, lung and liver. Transplacental carcinogenesis clearly occurs with other agents

  12. Transplacental Arsenic Carcinogenesis in Mice

    PubMed Central

    Waalkes, Michael P.; Liu, Jie; Diwan, Bhalchandra A.

    2007-01-01

    Our work has focused on the carcinogenic effects of in utero arsenic exposure in mice. Our data show a short period of maternal exposure to inorganic arsenic in the drinking water is an effective, multi-tissue carcinogen in the adult offspring. These studies have been reproduced in three temporally separate studies using two different mouse strains. In these studies pregnant mice were treated with drinking water containing sodium arsenite at up to 85 ppm arsenic from day 8 to 18 of gestation, and the offspring were observed for up to two years. The doses used in all these studies were well tolerated by both the dam and offspring. In C3H mice, two separate studies show male offspring exposed to arsenic in utero developed liver carcinoma and adrenal cortical adenoma in a dose-related fashion during adulthood. Prenatally exposed female C3H offspring show dose-related increases in ovarian tumors and lung carcinoma and in proliferative lesions (tumors plus preneoplastic hyperplasia) of the uterus and oviduct. In addition, prenatal arsenic plus postnatal exposure to the tumor promoter, 12-O-tetradecanoyl phorbol-13-acetate (TPA) in C3H mice produces excess lung tumors in both sexes and liver tumors in females. Male CD1 mice treated with arsenic in utero develop tumors of the liver and adrenal and renal hyperplasia while females develop tumors of urogenital system, ovary, uterus and adrenal and hyperplasia of the oviduct. Additional postnatal treatment with diethylstilbestrol or tamoxifen after prenatal arsenic in CD1 mice induces urinary bladder transitional cell proliferative lesions, including carcinoma and papilloma, and enhances the carcinogenic response in the liver of both sexes. Overall this model has provided convincing evidence that arsenic is a transplacental carcinogen in mice with the ability to target tissues of potential human relevance, such as the urinary bladder, lung and liver. Transplacental carcinogenesis clearly occurs with other agents in humans and

  13. Transgenic Mice Over-Expressing RBP4 Have RBP4-Dependent and Light-Independent Retinal Degeneration.

    PubMed

    Du, Mei; Phelps, Eric; Balangue, Michael J; Dockins, Aaron; Moiseyev, Gennadiy; Shin, Younghwa; Kane, Shelley; Otalora, Laura; Ma, Jian-Xing; Farjo, Rafal; Farjo, Krysten M

    2017-08-01

    Transgenic mice overexpressing serum retinol-binding protein (RBP4-Tg) develop progressive retinal degeneration, characterized by microglia activation, yet the precise mechanisms underlying retinal degeneration are unclear. Previous studies showed RBP4-Tg mice have normal ocular retinoid levels, suggesting that degeneration is independent of the retinoid visual cycle or light exposure. The present study addresses whether retinal degeneration is light-dependent and RBP4-dependent by testing the effects of dark-rearing and pharmacological lowering of serum RBP4 levels, respectively. RBP4-Tg mice reared on normal mouse chow in normal cyclic light conditions were directly compared to RBP4-Tg mice exposed to chow supplemented with the RBP4-lowering compound A1120 or dark-rearing conditions. Quantitative retinal histological analysis was conducted to assess retinal degeneration, and electroretinography (ERG) and optokinetic tracking (OKT) tests were performed to assess retinal and visual function. Ocular retinoids and bis-retinoid A2E were quantified. Dark-rearing RBP4-Tg mice effectively reduced ocular bis-retinoid A2E levels, but had no significant effect on retinal degeneration or dysfunction in RBP4-Tg mice, demonstrating that retinal degeneration is light-independent. A1120 treatment lowered serum RBP4 levels similar to wild-type mice, and prevented structural retinal degeneration. However, A1120 treatment did not prevent retinal dysfunction in RBP4-Tg mice. Moreover, RBP4-Tg mice on A1120 diet had significant worsening of OKT response and loss of cone photoreceptors compared to RBP4-Tg mice on normal chow. This may be related to the very significant reduction in retinyl ester levels in the retina of mice on A1120-supplemented diet. Retinal degeneration in RBP4-Tg mice is RBP4-dependent and light-independent.

  14. HEAO A-2 extragalactic results

    NASA Technical Reports Server (NTRS)

    Boldt, E. A.

    1979-01-01

    The all-sky surveys made with the A-2 instrument aboard HEAO-1 involved spectroscopy over a broad enough band width, with sufficient resolution, to obtain the basic spectral characteristics for two extreme aspects of the extragalactic X-ray sky. The overall spectrum (above 3 KeV) is remarkably well decribed by a thermal model. At the other extreme, the detailed broad-band observations of individual sources are restricted to objects within the present epoch. The objects include several individual active galaxies studied in detail for the first time as well as clusters of galaxies. Relating these results to the vast spatially unresolved hard X-ray flux measured with this instruments as well as the softer X-rays (at less than 3 keV) spatially resolved to high redshifts with the Einstein Observatory remains a challenge.

  15. Nonspecific resistance to Escherichia coli in mice.

    PubMed Central

    Shayegani, M; Parsons, L M

    1975-01-01

    Nonspecific cell-mediated immunity to a relatively virulent strain of Escherichia coli was studied in mice infected with Staphylococcus aureus and elicited with specific antigens. The infected and elicited mice were protected against as intraperitoneal challenge by E. coli for an observation period of 7 days, whereas normal mice, given the same number of bacteria, died within 18 to 24 h. However, the amount of time elapsing between elicitation and challenge greatly affected the rate of protection. Little or no protection was observed in mice injected with S. aureus but not elicited or in mice injected with staphylococcal antigens but not infected with staphylococci. PMID:1104478

  16. Lysosomal acid lipase regulates VLDL synthesis and insulin sensitivity in mice.

    PubMed

    Radović, Branislav; Vujić, Nemanja; Leopold, Christina; Schlager, Stefanie; Goeritzer, Madeleine; Patankar, Jay V; Korbelius, Melanie; Kolb, Dagmar; Reindl, Julia; Wegscheider, Martin; Tomin, Tamara; Birner-Gruenberger, Ruth; Schittmayer, Matthias; Groschner, Lukas; Magnes, Christoph; Diwoky, Clemens; Frank, Saša; Steyrer, Ernst; Du, Hong; Graier, Wolfgang F; Madl, Tobias; Kratky, Dagmar

    2016-08-01

    Lysosomal acid lipase (LAL) hydrolyses cholesteryl esters and triacylglycerols (TG) within lysosomes to mobilise NEFA and cholesterol. Since LAL-deficient (Lal (-/-) ) mice suffer from progressive loss of adipose tissue and severe accumulation of lipids in hepatic lysosomes, we hypothesised that LAL deficiency triggers alternative energy pathway(s). We studied metabolic adaptations in Lal (-/-) mice. Despite loss of adipose tissue, Lal (-/-) mice show enhanced glucose clearance during insulin and glucose tolerance tests and have increased uptake of [(3)H]2-deoxy-D-glucose into skeletal muscle compared with wild-type mice. In agreement, fasted Lal (-/-) mice exhibit reduced glucose and glycogen levels in skeletal muscle. We observed 84% decreased plasma leptin levels and significantly reduced hepatic ATP, glucose, glycogen and glutamine concentrations in fed Lal (-/-) mice. Markedly reduced hepatic acyl-CoA concentrations decrease the expression of peroxisome proliferator-activated receptor α (PPARα) target genes. However, treatment of Lal (-/-) mice with the PPARα agonist fenofibrate further decreased plasma TG (and hepatic glucose and glycogen) concentrations in Lal (-/-) mice. Depletion of hepatic nuclear factor 4α and forkhead box protein a2 in fasted Lal (-/-) mice might be responsible for reduced expression of microsomal TG transfer protein, defective VLDL synthesis and drastically reduced plasma TG levels. Our findings indicate that neither activation nor inactivation of PPARα per se but rather the availability of hepatic acyl-CoA concentrations regulates VLDL synthesis and subsequent metabolic adaptations in Lal (-/-) mice. We conclude that decreased plasma VLDL production enhances glucose uptake into skeletal muscle to compensate for the lack of energy supply.

  17. Hepatic Adaptation Compensates Inactivation of Intestinal Arginine Biosynthesis in Suckling Mice

    PubMed Central

    Marion, Vincent; Sankaranarayanan, Selvakumari; de Theije, Chiel; van Dijk, Paul; Hakvoort, Theo B. M.; Lamers, Wouter H.; Köhler, Eleonore S.

    2013-01-01

    Suckling mammals, including mice, differ from adults in the abundant expression of enzymes that synthesize arginine from citrulline in their enterocytes. To investigate the importance of the small-intestinal arginine synthesis for whole-body arginine production in suckling mice, we floxed exon 13 of the argininosuccinate synthetase (Ass) gene, which codes for a key enzyme in arginine biosynthesis, and specifically and completely ablated Ass in enterocytes by crossing Ass fl and Villin-Cre mice. Unexpectedly, Ass fl/fl /VilCre tg/- mice showed no developmental impairments. Amino-acid fluxes across the intestine, liver, and kidneys were calculated after determining the blood flow in the portal vein, and hepatic and renal arteries (86%, 14%, and 33%, respectively, of the transhepatic blood flow in 14-day-old mice). Relative to control mice, citrulline production in the splanchnic region of Ass fl/fl /VilCre tg/- mice doubled, while arginine production was abolished. Furthermore, the net production of arginine and most other amino acids in the liver of suckling control mice declined to naught or even changed to consumption in Ass fl/fl /VilCre tg/- mice, and had, thus, become remarkably similar to that of post-weaning wild-type mice, which no longer express arginine-biosynthesizing enzymes in their small intestine. The adaptive changes in liver function were accompanied by an increased expression of genes involved in arginine metabolism (Asl, Got1, Gpt2, Glud1, Arg1, and Arg2) and transport (Slc25a13, Slc25a15, and Slc3a2), whereas no such changes were found in the intestine. Our findings suggest that the genetic premature deletion of arginine synthesis in enterocytes causes a premature induction of the post-weaning pattern of amino-acid metabolism in the liver. PMID:23785515

  18. Differential requirement for satellite cells during overload-induced muscle hypertrophy in growing versus mature mice.

    PubMed

    Murach, Kevin A; White, Sarah H; Wen, Yuan; Ho, Angel; Dupont-Versteegden, Esther E; McCarthy, John J; Peterson, Charlotte A

    2017-07-10

    Pax7+ satellite cells are required for skeletal muscle fiber growth during post-natal development in mice. Satellite cell-mediated myonuclear accretion also appears to persist into early adulthood. Given the important role of satellite cells during muscle development, we hypothesized that the necessity of satellite cells for adaptation to an imposed hypertrophic stimulus depends on maturational age. Pax7 CreER -R26R DTA mice were treated for 5 days with vehicle (satellite cell-replete, SC+) or tamoxifen (satellite cell-depleted, SC-) at 2 months (young) and 4 months (mature) of age. Following a 2-week washout, mice were subjected to sham surgery or 10 day synergist ablation overload of the plantaris (n = 6-9 per group). The surgical approach minimized regeneration, de novo fiber formation, and fiber splitting while promoting muscle fiber growth. Satellite cell density (Pax7+ cells/fiber), embryonic myosin heavy chain expression (eMyHC), and muscle fiber cross sectional area (CSA) were evaluated via immunohistochemistry. Myonuclei (myonuclei/100 mm) were counted on isolated single muscle fibers. Tamoxifen treatment depleted satellite cells by ≥90% and prevented myonuclear accretion with overload in young and mature mice (p < 0.05). Satellite cells did not recover in SC- mice after overload. Average muscle fiber CSA increased ~20% in young SC+ (p = 0.07), mature SC+ (p < 0.05), and mature SC- mice (p < 0.05). In contrast, muscle fiber hypertrophy was prevented in young SC- mice. Muscle fiber number increased only in mature mice after overload (p < 0.05), and eMyHC expression was variable, specifically in mature SC+ mice. Reliance on satellite cells for overload-induced hypertrophy is dependent on maturational age, and global responses to overload differ in young versus mature mice.

  19. Collagen-induced arthritis in mice.

    PubMed

    Bevaart, Lisette; Vervoordeldonk, Margriet J; Tak, Paul P

    2010-01-01

    Collagen-induced arthritis (CIA) in mice is an animal model for rheumatoid arthritis (RA) and can be induced in DBA/1 and C57BL/6 mice using different protocols. The CIA model can be used to unravel mechanisms involved in the development of arthritis and is frequently used to study the effect of new therapeutics. The development of a CIA model in C57BL/6 mice recently enabled researchers to use knockout mice on this background for arthritis research.In this chapter, the protocol for induction of arthritis in both mice strains is described, including the monitoring of clinical arthritis and paw swelling in the mice during the experiment. Furthermore, protocols for decalcification of paws and for the detection of collagen-specific antibodies in mice sera are described.

  20. Mycobacterium tuberculosis interferes with the response to infection by inducing the host EphA2 receptor.

    PubMed

    Khounlotham, Manirath; Subbian, Selvakumar; Smith, Roger; Cirillo, Suat L G; Cirillo, Jeffrey D

    2009-06-15

    Mycobacterium tuberculosis is an unusual pathogen, persisting for years in infected persons despite an immune response. Erythropoietin-producing hepatoma (Eph) receptors are critical for tissue organization. One hallmark of tuberculosis is the presence of granulomas consisting of organized immune cells. The importance of granuloma structure makes it likely that Eph receptors play a role in immunity to tuberculosis. We infected mice with low doses of M. tuberculosis by the aerosol method and examined the effects on ephA gene expression, pathology, composition of lymphocytes in the lungs (by flow cytometry), migration of CD4+ and CD8+ T cells, and numbers of cytokine-expressing cells. Mice infected with M. tuberculosis displayed higher expression of ephA1 and ephA2 as well as ephrinA1, which encodes the ligand for EphA1 and EphA2. Interestingly, ephA2-/- mice displayed greater pathology, greater accumulation of T cells and dendritic cells, and higher levels of proinflammatory cytokines than did normal C57BL/6 mice. Furthermore, T cells from ephA2-/- mice migrated more efficiently than did those from C57BL/6 mice. These observations suggest that ephA-related genes may provide a mechanism that M. tuberculosis uses to circumvent the host response, given that accumulation of T cells appears to be due to the inhibition of immune cell migration by EphA2. Ultimately, the absence of ephA2 results in greater clearance of M. tuberculosis during the chronic phase of infection, suggesting that induction of ephA2 is important for the survival of M. tuberculosis during latency.

  1. Proteomic profile in glomeruli of type-2 diabetic KKAy mice using 2-dimensional differential gel electrophoresis.

    PubMed

    Liu, Xiaodan; Yang, Gang; Fan, Qiuling; Wang, Lining

    2014-12-17

    Diabetic nephropathy (DN) is a leading cause of end-stage renal disease. To search for glomerular proteins associated with early-stage DN, glomeruli of spontaneous type 2 diabetic KKAy mice were analyzed by 2-dimensional differential gel electrophoresis (2D-DIGE). Glomeruli of 20-week spontaneous type 2 diabetic KKAy mice and age-matched C57BL/6 mice were isolated by kidney perfusion with magnetic beads. Proteomic profiles of glomeruli were investigated by using 2D-DIGE and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Western blot analysis was used to confirm the results of proteomics. Immunohistochemical and semi-quantitative analysis were used to confirm the differential expression of prohibitin and annexin A2 in glomeruli. We identified 19 differentially expressed proteins - 17 proteins were significantly up-regulated and 2 proteins were significantly down-regulated in glomeruli of diabetic KKAy mice. Among them, prohibitin and annexin A2 were up-regulated and Western blot analysis validated the same result in proteomics. Immunohistochemical analysis also revealed up-regulation of prohibitin and annexin A2 in glomeruli of KKAy mice. Our findings suggest that prohibitin and annexin A2 may be associated with early-stage DN. Further functional research might help to reveal the pathogenesis of DN.

  2. Phospholipase A2 in cnidaria.

    PubMed

    Nevalainen, Timo J; Peuravuori, Heikki J; Quinn, Ronald J; Llewellyn, Lyndon E; Benzie, John A H; Fenner, Peter J; Winkel, Ken D

    2004-12-01

    Phospholipase A2 (PLA2) is an enzyme present in snake and other venoms and body fluids. We measured PLA2 catalytic activity in tissue homogenates of 22 species representing the classes Anthozoa, Hydrozoa, Scyphozoa and Cubozoa of the phylum Cnidaria. High PLA2 levels were found in the hydrozoan fire coral Millepora sp. (median 735 U/g protein) and the stony coral Pocillopora damicornis (693 U/g) that cause skin irritation upon contact. High levels of PLA2 activity were also found in the acontia of the sea anemone Adamsia carciniopados (293 U/g). Acontia are long threads containing nematocysts and are used in defense and aggression by the animal. Tentacles of scyphozoan and cubozoan species had high PLA2 activity levels: those of the multitentacled box jellyfish Chironex fleckeri contained 184 U/g PLA2 activity. The functions of cnidarian PLA2 may include roles in the capture and digestion of prey and defense of the animal. The current observations support the idea that cnidarian PLA2 may participate in the sting site irritation and systemic envenomation syndrome resulting from contact with cnidarians.

  3. Magnetic eye tracking in mice

    PubMed Central

    Payne, Hannah L

    2017-01-01

    Eye movements provide insights about a wide range of brain functions, from sensorimotor integration to cognition; hence, the measurement of eye movements is an important tool in neuroscience research. We describe a method, based on magnetic sensing, for measuring eye movements in head-fixed and freely moving mice. A small magnet was surgically implanted on the eye, and changes in the magnet angle as the eye rotated were detected by a magnetic field sensor. Systematic testing demonstrated high resolution measurements of eye position of <0.1°. Magnetic eye tracking offers several advantages over the well-established eye coil and video-oculography methods. Most notably, it provides the first method for reliable, high-resolution measurement of eye movements in freely moving mice, revealing increased eye movements and altered binocular coordination compared to head-fixed mice. Overall, magnetic eye tracking provides a lightweight, inexpensive, easily implemented, and high-resolution method suitable for a wide range of applications. PMID:28872455

  4. Trace fear conditioning in mice.

    PubMed

    Lugo, Joaquin N; Smith, Gregory D; Holley, Andrew J

    2014-03-20

    In this experiment we present a technique to measure learning and memory. In the trace fear conditioning protocol presented here there are five pairings between a neutral stimulus and an unconditioned stimulus. There is a 20 sec trace period that separates each conditioning trial. On the following day freezing is measured during presentation of the conditioned stimulus (CS) and trace period. On the third day there is an 8 min test to measure contextual memory. The representative results are from mice that were presented with the aversive unconditioned stimulus (shock) compared to mice that received the tone presentations without the unconditioned stimulus. Trace fear conditioning has been successfully used to detect subtle learning and memory deficits and enhancements in mice that are not found with other fear conditioning methods. This type of fear conditioning is believed to be dependent upon connections between the medial prefrontal cortex and the hippocampus. One current controversy is whether this method is believed to be amygdala-independent. Therefore, other fear conditioning testing is needed to examine amygdala-dependent learning and memory effects, such as through the delay fear conditioning.

  5. Metabolism of paclitaxel in mice.

    PubMed

    Bardelmeijer, Heleen A; Oomen, Ingrid A M; Hillebrand, Michel J X; Beijnen, Jos H; Schellens, Jan H M; van Tellingen, Olaf

    2003-03-01

    Previous mass balance studies in humans and mice have shown that the fecal and urinary recovery of paclitaxel and known metabolites (3' -hydroxypaclitaxel, 6alpha-hydroxypaclitaxel and 3',6alpha-dihydroxypaclitaxel) was not complete. Obviously this discrepancy is caused by the existence of other yet unknown metabolites. Mdr1a/1b(-/-) mice excrete very low quantities of unchanged paclitaxel. We have therefore used these mice receiving i.v. [3H]paclitaxel to further study the metabolic fate of paclitaxel. The major part of the radiolabel, being 70%, was excreted in the feces. A lipophilic sample, containing about 70% of the radioactivity present in the feces sample, was obtained by diethyl ether extraction. The aqueous residue containing about 30% of the radioactivity was further extracted using methanol. The high-performance liquid chromatography (HPLC) chromatograms of the lipophilic and aqueous sample revealed two and five putative new metabolites of paclitaxel, respectively. The HPLC fractions containing substantial amounts of radioactivity were subjected to tandem mass spectrometry. Two novel monohydroxylated paclitaxel structures were identified, which are probably 2m-hydroxypaclitaxel and 19-hydroxypaclitaxel, structures previously identified in rats. Including these metabolites, about 60% of the mass balance of paclitaxel could be quantified. Copyright 2003 Lippincott Williams & Wilkins

  6. Gut microbiota modulation with norfloxacin and ampicillin enhances glucose tolerance in mice.

    PubMed

    Membrez, Mathieu; Blancher, Florence; Jaquet, Muriel; Bibiloni, Rodrigo; Cani, Patrice D; Burcelin, Rémy G; Corthesy, Irène; Macé, Katherine; Chou, Chieh Jason

    2008-07-01

    Recent data suggest that the gut microbiota plays a significant role in fat accumulation. However, it is not clear whether gut microbiota is involved in the pathophysiology of type 2 diabetes. To assess this issue, we modulated gut microbiota via antibiotics administration in two different mouse models with insulin resistance. Results from dose-determination studies showed that a combination of norfloxacin and ampicillin, at a dose of 1 g/L, maximally suppressed the numbers of cecal aerobic and anaerobic bacteria in ob/ob mice. After a 2-wk intervention with the antibiotic combination, both ob/ob and diet-induced obese and insulin-resistant mice showed a significant improvement in fasting glycemia and oral glucose tolerance. The improved glycemic control was independent of food intake or adiposity because pair-fed ob/ob mice were as glucose intolerant as the control ob/ob mice. Reduced liver triglycerides and increased liver glycogen correlated with improved glucose tolerance in the treated mice. Concomitant reduction of plasma lipopolysaccharides and increase of adiponectin further supported the antidiabetic effects of the antibiotic treatment in ob/ob mice. In summary, modulation of gut microbiota ameliorated glucose tolerance of mice by altering the expression of hepatic and intestinal genes involved in inflammation and metabolism, and by changing the hormonal, inflammatory, and metabolic status of the host.

  7. Influence of Chronic Moderate Sleep Restriction and Exercise on Inflammation and Carcinogenesis in Mice

    PubMed Central

    Zielinski, Mark R.; Davis, J. Mark; Fadel, James R.; Youngstedt, Shawn D.

    2013-01-01

    The effects of chronic moderate sleep restriction and exercise training on carcinogenesis were examined in adenomatous polyposis coli multiple intestinal neoplasma (APC Min+/-) mice, a genetic strain which is predisposed to developing adenomatous polyposis. The mice were randomized to one of four 11 week treatments in a 2×2 design involving sleep restriction (by 4 h/day) vs. normal sleep and exercise training (1 h/day) vs. sedentary control. Wild-type control mice underwent identical experimental treatments. Compared with the wild-type mice, APC Min+/- mice had disrupted hematology and enhanced pro-inflammatory cytokine production from peritoneal exudate cells. Among the APC Min+/- mice, consistent interactions of sleep loss and exercise were found for measures of polyp formation, inflammation, and hematology. Sleep loss had little effect on these variables under sedentary conditions, but sleep loss had clear detrimental effects under exercise conditions. Exercise training resulted in improvements in these measures under normal sleep conditions, but exercise tended to elicit no effect or to exacerbate the effects of sleep restriction. Significant correlations of inflammation with polyp burden were observed. Among wild-type mice, similar, but less consistent interactions of sleep restriction and exercise were found. These data suggest that the benefits of exercise on carcinogenesis and immune function were impaired by chronic moderate sleep restriction, and that harmful effects of sleep restriction were generally realized only in the presence of exercise. PMID:22433899

  8. Eucaloric Ketogenic Diet Reduces Hypoglycemia and Inflammation in Mice with Endotoxemia.

    PubMed

    Nandivada, Prathima; Fell, Gillian L; Pan, Amy H; Nose, Vania; Ling, Pei-Ra; Bistrian, Bruce R; Puder, Mark

    2016-06-01

    Dietary strategies to alter the immune response to acute inflammation have the potential to improve outcomes in critically ill patients. A eucaloric ketogenic diet (EKD), composed predominantly of fat with very small amounts of carbohydrate, can provide adequate caloric support while minimizing spikes in blood glucose and reducing oxidative stress. The purpose of this study was to evaluate the effects of an EKD on glycemic control and the inflammatory response after acute endotoxemia in mice. Mice received either an EKD or a carbohydrate-based control diet (CD) for 4 weeks. Animals subsequently underwent either a 2-h fast (postprandial) or an overnight fast (postabsorptive), and half of the animals in each diet group were randomized to receive either intraperitoneal lipopolysaccharide (1 mg/kg) or an equivalent volume of saline. Glycemic response, insulin resistance, inflammatory cytokine levels, and the expression of key inflammatory and metabolic genes were measured. After endotoxin challenge, hypoglycemia was more frequent in mice fed a CD than an EKD in the postprandial period. This was due in part to the preservation of hepatic glycogen stores despite endotoxin exposure and prolonged fasting in mice fed an EKD. Furthermore, mice fed the CD had higher levels of IL-6 and TNF-α in the postabsorptive period, with a fivefold higher expression of hepatic NFκB compared to mice fed the EKD in both fasting periods. These results suggest that the unique metabolic state induced by an EKD can alter the response to acute inflammation in mice.

  9. Hepatic response to oxidative injury in long-lived Ames dwarf mice.

    PubMed

    Sun, Liou Y; Bokov, Alex F; Richardson, Arlan; Miller, Richard A

    2011-01-01

    Multiple stress resistance pathways were evaluated in the liver of Ames dwarf mice before and after exposure to the oxidative toxin diquat, seeking clues to the exceptional longevity conferred by this mutation. Before diquat treatment, Ames dwarf mice, compared with nonmutant littermate controls, had 2- to 6-fold higher levels of expression of mRNAs for immediate early genes and 2- to 5-fold higher levels of mRNAs for genes dependent on the transcription factor Nrf2. Diquat led to a 2-fold increase in phosphorylation of the stress kinase ERK in control (but not Ames dwarf) mice and to a 50% increase in phosphorylation of the kinase JNK2 in Ames dwarf (but not control) mice. Diquat induction of Nrf2 protein was higher in dwarf mice than in controls. Of 6 Nrf2-responsive genes evaluated, 4 (HMOX, NQO-1, MT-1, and MT-2) remained 2- to 10-fold lower in control than in dwarf liver after diquat, and the other 2 (GCLM and TXNRD) reached levels already seen in dwarf liver at baseline. Thus, livers of Ames dwarf mice differ systematically from controls in multiple stress resistance pathways before and after exposure to diquat, suggesting mechanisms for stress resistance and extended longevity in Ames dwarf mice.

  10. Genetic variation of iron-induced uroporphyria in mice.

    PubMed Central

    Smith, A G; Francis, J E

    1993-01-01

    Iron overload causes inhibition of hepatic uroporphyrinogen decarboxylase (UROD) and uroporphyria in C57BL/10ScSn but not DBA/2 mice [Smith, Cabral, Carthew, Francis and Manson (1989) Int. J. Cancer 43, 492-496]. We have investigated the induction of uroporphyria in 12 inbred strains of mice 25 weeks after iron treatment (600 mg/kg) to determine if there was any correlation with the Ah locus. Under these conditions, inhibition of UROD occurred to varying degrees in Ahd mice (SWR and AKR) as well as nominally Ahb-1 (C57BL/6J, C57BL/10ScSn and C57BL/10-cc) and Ahb-2 strains (BALB/c and C3H/HeJ). Five other Ahb or Ahd strains (C57BL/Ks, A/J, CBA/J, LP and DBA/2) were unaffected. Thus there appeared to be no correlation with the Ah phenotype and this illustrated that some other variable inherited factors are involved. Comparisons between another susceptible strain, A2G, and the congenic A2G-hr/+strain (carrying the recessive hr gene) showed a modulating influence associated with the hr locus. In contrast with individual mice of inbred strains, which showed consistent responses to iron, those of the outbred MF1 strain showed a spectrum of sensitivities as might be expected for a heterogeneic stock. The rate of porphyria development was accelerated by administration of 5-aminolaevulinic acid (5-ALA) in the drinking water, but this did not overcome strain differences. Among four strains the order of susceptibility was SWR > C57BL/10ScSn > C57B1/6J > DBA/2 (the last strain was completely resistant). With degrees of iron loading greater than 600 mg of Fe/kg (1200-1800 mg of Fe/kg) C57BL/10ScSn mice (after 20 weeks) and SWR mice (after 5 weeks which included 4 weeks of 5-ALA treatment) had less inhibition of UROD and a lower uroporphyric response, showing that there was an optimum level of liver iron concentration. Studies on selected microsomal enzyme activities associated with cytochrome P-450 showed no correlation with the propensities of strains to develop porphyria

  11. A2BR Adenosine Receptor Modulates Sweet Taste in Circumvallate Taste Buds

    PubMed Central

    Yang, Dan; Shultz, Nicole; Vandenbeuch, Aurelie; Ravid, Katya; Kinnamon, Sue C.; Finger, Thomas E.

    2012-01-01

    In response to taste stimulation, taste buds release ATP, which activates ionotropic ATP receptors (P2X2/P2X3) on taste nerves as well as metabotropic (P2Y) purinergic receptors on taste bud cells. The action of the extracellular ATP is terminated by ectonucleotidases, ultimately generating adenosine, which itself can activate one or more G-protein coupled adenosine receptors: A1, A2A, A2B, and A3. Here we investigated the expression of adenosine receptors in mouse taste buds at both the nucleotide and protein expression levels. Of the adenosine receptors, only A2B receptor (A2BR) is expressed specifically in taste epithelia. Further, A2BR is expressed abundantly only in a subset of taste bud cells of posterior (circumvallate, foliate), but not anterior (fungiform, palate) taste fields in mice. Analysis of double-labeled tissue indicates that A2BR occurs on Type II taste bud cells that also express Gα14, which is present only in sweet-sensitive taste cells of the foliate and circumvallate papillae. Glossopharyngeal nerve recordings from A2BR knockout mice show significantly reduced responses to both sucrose and synthetic sweeteners, but normal responses to tastants representing other qualities. Thus, our study identified a novel regulator of sweet taste, the A2BR, which functions to potentiate sweet responses in posterior lingual taste fields. PMID:22253866

  12. The adenosine a2a receptor inhibits matrix-induced inflammation in a novel fashion.

    PubMed

    Scheibner, Kara A; Boodoo, Sada; Collins, Samuel; Black, Katharine E; Chan-Li, Yee; Zarek, Paul; Powell, Jonathan D; Horton, Maureen R

    2009-03-01

    Endogenous mediators within the inflammatory milieu play a critical role in directing the scope, duration, and resolution of inflammation. High-molecular-weight extracellular matrix hyaluronan (HA) helps to maintain homeostasis. During inflammation, hyaluronan is broken down into fragments that induce chemokines and cytokines, thereby augmenting the inflammatory response. Tissue-derived adenosine, released during inflammation, inhibits inflammation via the anti-inflammatory A2 adenosine receptor (A2aR). We demonstrate that adenosine modulates HA-induced gene expression via the A2aR. A2aR stimulation inhibits HA fragment-induced pro-fibrotic genes TNF-alpha, keratinocyte chemoattractant (KC), macrophage inflammatory protein (MIP)-2, and MIP-1alpha while simultaneously synergizing with hyaluronan fragments to up-regulate the TH1 cytokine IL-12. Interestingly, A2aR stimulation mediates these affects via the novel cAMP-activated guanine nucleotide exchange factor EPAC. In addition, A2aR-null mice are more susceptible to bleomycin-induced lung injury, consistent with a role for endogenous adenosine in inhibiting the inflammation that may lead to fibrosis. Indeed, the bleomycin treated A2aR-null mice demonstrate increased lung inflammation, HA accumulation, and histologic damage. Overall, our data elucidate the opposing roles of tissue-derived HA fragments and adenosine in regulating noninfectious lung inflammation and support the pursuit of A2aR agonists as a means of pharmacologically inhibiting inflammation that may lead to fibrosis.

  13. Mushroom Ganoderma lucidum Prevents Colitis-Associated Carcinogenesis in Mice

    PubMed Central

    Sliva, Daniel; Loganathan, Jagadish; Jiang, Jiahua; Jedinak, Andrej; Lamb, John G.; Terry, Colin; Baldridge, Lee Ann; Adamec, Jiri; Sandusky, George E.; Dudhgaonkar, Shailesh

    2012-01-01

    Background Epidemiological studies suggest that mushroom intake is inversely correlated with gastric, gastrointestinal and breast cancers. We have recently demonstrated anticancer and anti-inflammatory activity of triterpene extract isolated from mushroom Ganoderma lucidum (GLT). The aim of the present study was to evaluate whether GLT prevents colitis-associated carcinogenesis in mice. Methods/Principal Findings Colon carcinogenesis was induced by the food-borne carcinogen (2-Amino-1-methyl-6-phenylimidazol[4,5-b]pyridine [PhIP]) and inflammation (dextran sodium sulfate [DSS]) in mice. Mice were treated with 0, 100, 300 and 500 mg GLT/kg of body weight 3 times per week for 4 months. Cell proliferation, expression of cyclin D1 and COX-2 and macrophage infiltration was assessed by immunohistochemistry. The effect of GLT on XRE/AhR, PXR and rPXR was evaluated by the reporter gene assays. Expression of metabolizing enzymes CYP1A2, CYP3A1 and CYP3A4 in colon tissue was determined by immunohistochemistry. GLT treatment significantly suppressed focal hyperplasia, aberrant crypt foci (ACF) formation and tumor formation in mice exposed to PhIP/DSS. The anti-proliferative effects of GLT were further confirmed by the decreased staining with Ki-67 in colon tissues. PhIP/DSS-induced colon inflammation was demonstrated by the significant shortening of the large intestine and macrophage infiltrations, whereas GLT treatment prevented the shortening of colon lengths, and reduced infiltration of macrophages in colon tissue. GLT treatment also significantly down-regulated PhIP/DSS-dependent expression of cyclin D1, COX-2, CYP1A2 and CYP3A4 in colon tissue. Conclusions Our data suggest that GLT could be considered as an alternative dietary approach for the prevention of colitis-associated cancer. PMID:23118901

  14. Mushroom Ganoderma lucidum prevents colitis-associated carcinogenesis in mice.

    PubMed

    Sliva, Daniel; Loganathan, Jagadish; Jiang, Jiahua; Jedinak, Andrej; Lamb, John G; Terry, Colin; Baldridge, Lee Ann; Adamec, Jiri; Sandusky, George E; Dudhgaonkar, Shailesh

    2012-01-01

    Epidemiological studies suggest that mushroom intake is inversely correlated with gastric, gastrointestinal and breast cancers. We have recently demonstrated anticancer and anti-inflammatory activity of triterpene extract isolated from mushroom Ganoderma lucidum (GLT). The aim of the present study was to evaluate whether GLT prevents colitis-associated carcinogenesis in mice. Colon carcinogenesis was induced by the food-borne carcinogen (2-Amino-1-methyl-6-phenylimidazol[4,5-b]pyridine [PhIP]) and inflammation (dextran sodium sulfate [DSS]) in mice. Mice were treated with 0, 100, 300 and 500 mg GLT/kg of body weight 3 times per week for 4 months. Cell proliferation, expression of cyclin D1 and COX-2 and macrophage infiltration was assessed by immunohistochemistry. The effect of GLT on XRE/AhR, PXR and rPXR was evaluated by the reporter gene assays. Expression of metabolizing enzymes CYP1A2, CYP3A1 and CYP3A4 in colon tissue was determined by immunohistochemistry. GLT treatment significantly suppressed focal hyperplasia, aberrant crypt foci (ACF) formation and tumor formation in mice exposed to PhIP/DSS. The anti-proliferative effects of GLT were further confirmed by the decreased staining with Ki-67 in colon tissues. PhIP/DSS-induced colon inflammation was demonstrated by the significant shortening of the large intestine and macrophage infiltrations, whereas GLT treatment prevented the shortening of colon lengths, and reduced infiltration of macrophages in colon tissue. GLT treatment also significantly down-regulated PhIP/DSS-dependent expression of cyclin D1, COX-2, CYP1A2 and CYP3A4 in colon tissue. Our data suggest that GLT could be considered as an alternative dietary approach for the prevention of colitis-associated cancer.

  15. Electromagnetic treatment to old Alzheimer's mice reverses β-amyloid deposition, modifies cerebral blood flow, and provides selected cognitive benefit.

    PubMed

    Arendash, Gary W; Mori, Takashi; Dorsey, Maggie; Gonzalez, Rich; Tajiri, Naoki; Borlongan, Cesar

    2012-01-01

    Few studies have investigated physiologic and cognitive effects of "long-term" electromagnetic field (EMF) exposure in humans or animals. Our recent studies have provided initial insight into the long-term impact of adulthood EMF exposure (GSM, pulsed/modulated, 918 MHz, 0.25-1.05 W/kg) by showing 6+ months of daily EMF treatment protects against or reverses cognitive impairment in Alzheimer's transgenic (Tg) mice, while even having cognitive benefit to normal mice. Mechanistically, EMF-induced cognitive benefits involve suppression of brain β-amyloid (Aβ) aggregation/deposition in Tg mice and brain mitochondrial enhancement in both Tg and normal mice. The present study extends this work by showing that daily EMF treatment given to very old (21-27 month) Tg mice over a 2-month period reverses their very advanced brain Aβ aggregation/deposition. These very old Tg mice and their normal littermates together showed an increase in general memory function in the Y-maze task, although not in more complex tasks. Measurement of both body and brain temperature at intervals during the 2-month EMF treatment, as well as in a separate group of Tg mice during a 12-day treatment period, revealed no appreciable increases in brain temperature (and no/slight increases in body temperature) during EMF "ON" periods. Thus, the neuropathologic/cognitive benefits of EMF treatment occur without brain hyperthermia. Finally, regional cerebral blood flow in cerebral cortex was determined to be reduced in both Tg and normal mice after 2 months of EMF treatment, most probably through cerebrovascular constriction induced by freed/disaggregated Aβ (Tg mice) and slight body hyperthermia during "ON" periods. These results demonstrate that long-term EMF treatment can provide general cognitive benefit to very old Alzheimer's Tg mice and normal mice, as well as reversal of advanced Aβ neuropathology in Tg mice without brain heating. Results further underscore the potential for EMF treatment

  16. Thyroid hormone interacts with the sympathetic nervous system to modulate bone mass and structure in young adult mice.

    PubMed

    Fonseca, Tatiana L; Teixeira, Marilia B C G; Miranda-Rodrigues, Manuela; Rodrigues-Miranda, Manuela; Silva, Marcos V; Martins, Gisele M; Costa, Cristiane C; Arita, Danielle Y; Perez, Juliana D; Casarini, Dulce E; Brum, Patricia C; Gouveia, Cecilia H A

    2014-08-15

    To investigate whether thyroid hormone (TH) interacts with the sympathetic nervous system (SNS) to modulate bone mass and structure, we studied the effects of daily T3 treatment in a supraphysiological dose for 12 wk on the bone of young adult mice with chronic sympathetic hyperactivity owing to double-gene disruption of adrenoceptors that negatively regulate norepinephrine release, α(2A)-AR, and α(2C)-AR (α(2A/2C)-AR(-/-) mice). As expected, T3 treatment caused a generalized decrease in the areal bone mineral density (aBMD) of WT mice (determined by DEXA), followed by deleterious effects on the trabecular and cortical bone microstructural parameters (determined by μCT) of the femur and vertebra and on the biomechanical properties (maximum load, ultimate load, and stiffness) of the femur. Surprisingly, α(2A/2C)-AR(-/-) mice were resistant to most of these T3-induced negative effects. Interestingly, the mRNA expression of osteoprotegerin, a protein that limits osteoclast activity, was upregulated and downregulated by T3 in the bone of α(2A/2C)-AR(-/-) and WT mice, respectively. β1-AR mRNA expression and IGF-I serum levels, which exert bone anabolic effects, were increased by T3 treatment only in α(2A/2C)-AR(-/-) mice. As expected, T3 inhibited the cell growth of calvaria-derived osteoblasts isolated from WT mice, but this effect was abolished or reverted in cells isolated from KO mice. Collectively, these findings support the hypothesis of a TH-SNS interaction to control bone mass and structure of young adult mice and suggests that this interaction may involve α2-AR signaling. Finally, the present findings offer new insights into the mechanisms through which TH regulates bone mass, structure, and physiology. Copyright © 2014 the American Physiological Society.

  17. Propagating Humanized BLT Mice for the Study of Human Immunology and Immunotherapy.

    PubMed

    Smith, Drake J; Lin, Levina J; Moon, Heesung; Pham, Alexander T; Wang, Xi; Liu, Siyuan; Ji, Sunjong; Rezek, Valerie; Shimizu, Saki; Ruiz, Marlene; Lam, Jennifer; Janzen, Deanna M; Memarzadeh, Sanaz; Kohn, Donald B; Zack, Jerome A; Kitchen, Scott G; An, Dong Sung; Yang, Lili

    2016-12-15

    The humanized bone marrow-liver-thymus (BLT) mouse model harbors a nearly complete human immune system, therefore providing a powerful tool to study human immunology and immunotherapy. However, its application is greatly limited by the restricted supply of human CD34 + hematopoietic stem cells and fetal thymus tissues that are needed to generate these mice. The restriction is especially significant for the study of human immune systems with special genetic traits, such as certain human leukocyte antigen (HLA) haplotypes or monogene deficiencies. To circumvent this critical limitation, we have developed a method to quickly propagate established BLT mice. Through secondary transfer of bone marrow cells and human thymus implants from BLT mice into NSG (NOD/SCID/IL-2Rγ -/- ) recipient mice, we were able to expand one primary BLT mouse into a colony of 4-5 proBLT (propagated BLT) mice in 6-8 weeks. These proBLT mice reconstituted human immune cells, including T cells, at levels comparable to those of their primary BLT donor mouse. They also faithfully inherited the human immune cell genetic traits from their donor BLT mouse, such as the HLA-A2 haplotype that is of special interest for studying HLA-A2-restricted human T cell immunotherapies. Moreover, an EGFP reporter gene engineered into the human immune system was stably passed from BLT to proBLT mice, making proBLT mice suitable for studying human immune cell gene therapy. This method provides an opportunity to overcome a critical hurdle to utilizing the BLT humanized mouse model and enables its more widespread use as a valuable preclinical research tool.

  18. The SecA2 Secretion Factor of Mycobacterium tuberculosis Promotes Growth in Macrophages and Inhibits the Host Immune Response▿

    PubMed Central

    Kurtz, Sherry; McKinnon, Karen P.; Runge, Marschall S.; Ting, Jenny P.-Y.; Braunstein, Miriam

    2006-01-01

    The SecA protein is present in all bacteria, and it is a central component of the general Sec-dependent protein export pathway. An unusual property of Mycobacterium tuberculosis is the presence of two SecA proteins: SecA1, the essential “housekeeping” SecA, and SecA2, the accessory secretion factor. Here, we report that a ΔsecA2 mutant of M. tuberculosis was defective for growth in the early stages of low-dose aerosol infection of C57BL/6 mice, a time during which the bacillus is primarily replicating in macrophages. Consistent with this in vivo phenotype, we found that the ΔsecA2 mutant was defective for growth in macrophages from C57BL/6 mice. The ΔsecA2 mutant was also attenuated for growth in macrophages from phox−/− mice and from NOS2−/− mice. These mice are defective in the reactive oxygen intermediate (ROI)-generating phagocyte oxidase and the reactive nitrogen intermediate (RNI)-generating inducible nitric oxide synthase, respectively. This indicated a role for SecA2 in the intracellular growth of M. tuberculosis that is independent of protecting against these ROIs or RNIs. Macrophages infected with the ΔsecA2 mutant produced higher levels of tumor necrosis factor alpha, interleukin-6, RNI, and gamma interferon-induced major histocompatibility complex class II. This demonstrated a function for M. tuberculosis SecA2 in suppressing macrophage immune responses, which could explain the role of SecA2 in intracellular growth. Our results provide another example of a relationship between M. tuberculosis virulence and inhibition of the host immune response. PMID:17030572

  19. Species differences in methanol and formic acid pharmacokinetics in mice, rabbits and primates

    SciTech Connect

    Sweeting, J. Nicole; Siu, Michelle; McCallum, Gordon P.

    2010-08-15

    Methanol (MeOH) is metabolized primarily by alcohol dehydrogenase in humans, but by catalase in rodents, with species variations in the pharmacokinetics of its formic acid (FA) metabolite. The teratogenic potential of MeOH in humans is unknown, and its teratogenicity in rodents may not accurately reflect human developmental risk due to differential species metabolism, as for some other teratogens. To determine if human MeOH metabolism might be better reflected in rabbits than rodents, the plasma pharmacokinetics of MeOH and FA were compared in male CD-1 mice, New Zealand white rabbits and cynomolgus monkeys over time (24, 48 and 6 h, respectively)more » following a single intraperitoneal injection of 0.5 or 2 g/kg MeOH or its saline vehicle. Following the high dose, MeOH exhibited saturated elimination kinetics in all 3 species, with similar peak concentrations and a 2.5-fold higher clearance in mice than rabbits. FA accumulation within 6 h in primates was 5-fold and 43-fold higher than in rabbits and mice respectively, with accumulation being 10-fold higher in rabbits than mice. Over 48 h, FA accumulation was nearly 5-fold higher in rabbits than mice. Low-dose MeOH in mice and rabbits resulted in similarly saturated MeOH elimination in both species, but with approximately 2-fold higher clearance rates in mice. FA accumulation was 3.8-fold higher in rabbits than mice. Rabbits more closely than mice reflected primates for in vivo MeOH metabolism, and particularly FA accumulation, suggesting that developmental studies in rabbits may be useful for assessing potential human teratological risk.« less

  20. How Ketamine Affects Livers of Pregnant Mice and Developing Mice?

    PubMed

    Cheung, Hoi Man; Chow, Tony Chin Hung; Yew, David Tai Wai

    2017-05-19

    It is well known that ketamine abuse can induce liver damage in adult addicts, but the effects of ketamine abuse in pregnant mothers on their offspring have received less attention. In this study, we investigated the effects of 5-day ketamine injections (30 mg/kg) to pregnant Institute for Cancer Research (ICR) mice during early gestation or mid-gestation on the aspartate aminotransferase (AST) and alkaline phosphatase (ALP) activities of the mothers and the offspring. We also looked into whether administering ketamine treatment to the mothers had any effects on the extent of fibrosis, cell proliferation and cell death in the livers of the newborns. No significant biochemical differences were found between treatment and control groups in the mothers. In the offspring, ketamine treatment mildly suppressed the gradual increase of hepatic AST activity in neonates during liver maturation. Measurements of hepatic ALP activity and lactic acid dehydrogenase (LDH) immunoreactivity revealed that ketamine treatment may lead to increased cell death. Proliferation of liver cells of the newborns was also retarded as shown by reduced proliferative cell nuclear antigen (PCNA) immunoreactivity in the ketamine groups. No obvious fibrosis was evident. Thus, we demonstrated that ketamine administration to pregnant mice suppressed hepatic development and also induced liver cell death of the offspring.

  1. A 2A adenosine receptor regulates glia proliferation and pain after peripheral nerve injury.

    PubMed

    Bura, S Andreea; Nadal, Xavier; Ledent, Catherine; Maldonado, Rafael; Valverde, Olga

    2008-11-15

    Peripheral nerve injury produces a persistent neuropathic pain state characterized by spontaneous pain, allodynia and hyperalgesia. In this study, we evaluated the possible involvement of A 2ARs in the development of neuropathic pain and the expression of microglia and astrocytes in the spinal cord after sciatic nerve injury. For this purpose, partial ligation of the sciatic nerve was performed in A 2A knockout mice and wild-type littermates. The development of mechanical and thermal allodynia, as well as thermal hyperalgesia was evaluated by using the von Frey filament model, the cold-plate test and the plantar test, respectively. In wild-type animals, sciatic nerve injury led to a neuropathic pain syndrome that was revealed in these three nociceptive behavioural tests. However, a significant decrease of the mechanical allodynia and a suppression of thermal hyperalgesia and allodynia were observed in A 2AR deficient mice. The expression of microglia and astrocytes was enhanced in wild-type mice exposed to sciatic nerve injury and this response was attenuated in knockout animals. Taken together, our results demonstrate the involvement of A 2ARs in the control of neuropathic pain and propose this receptor as an interesting target for the development of new drugs for the management of this clinical syndrome.

  2. 3-Acetylpyridine Neurotoxicity in Mice

    PubMed Central

    Wecker, L.; Marrero-Rosado, B.; Engberg, M.E.; Johns, B.E.; Philpot, R.M.

    2016-01-01

    3-acetylpyridine (3-AP) is a metabolic antagonist used in research to decrease levels of nicotinamide (niacinamide) in laboratory animals. The administration of 3-AP followed by nicotinamide to rats leads to the selective destruction of neurons in the medial inferior olive, resulting in a loss of climbing fibers innervating cerebellar Purkinje cells and a consequent ataxia manifest by alterations in both balance and gait. Although 3-AP has also been administered to mice to destroy neurons in the inferior olive, there are limited studies quantifying the consequent effects on balance, and no studies on gait. Further, the relationship between 3-AP-induced lesions of the inferior olive and behavior has not been elucidated. Because 3-AP continues to be used for experiments involving mice, this study characterized the effects of this toxin on both balance and gait, and on the neuronal integrity of several brain regions involved in motor coordination. Results indicate that C57BL/6 mice are less sensitive to the neurotoxic effects of 3-AP than rats, and a dose more than 6.5 times that used for rats produces deficits in both balance and gait comparable to those in rats. This dose led to a significant (p< 0.05) loss of NeuN(+) neurons in several subregions of the inferior olive including the rostral medial nucleus, dorsomedial cell column, ventrolateral protrusion, and cap of Kooy. Further, the number of NeuN(+) neurons in these subregions, with the exception of the dorsomedial cell column, was significantly (p<0.05) related to rotorod performance, implicating their involvement in this behavior. PMID:27986589

  3. Arthropod transmission of Eperythrozoon coccoides in mice.

    PubMed

    Berkenkamp, S D; Wescott, R B

    1988-08-01

    The association of Eperythrozoon coccoides infection in laboratory mice, with commonly encountered external parasites, was examined. Transmission of E. coccoides was achieved by infesting recipient mice with as few as 10 live Polyplax serrata immediately after they were obtained from donor mice infected with E. coccoides. Polyplax serrata removed from such hosts and fasted for 24 hours also were able to initiate E. coccoides infections in recipient mice. Transovarial transmission of E. coccoides through P. serrata was not demonstrated. Transmission of E. coccoides by Myocoptes musculinus, Myobia musculi and Radfordia affinis was not observed.

  4. Testosterone and Dihydrotestosterone Differentially Improve Cognition in Aged Female Mice

    ERIC Educational Resources Information Center

    Benice, Ted S.; Raber, Jacob

    2009-01-01

    Compared with age-matched male mice, female mice experience a more severe age-related cognitive decline (ACD). Since androgens are less abundant in aged female mice compared with aged male mice, androgen supplementation may enhance cognition in aged female mice. To test this, we assessed behavioral performance on a variety of tasks in 22- to…

  5. A potent adjuvant effect of a CD1d-binding NKT cell ligand in human immune system mice

    PubMed Central

    Li, Xiangming; Huang, Jing; Kaneko, Izumi; Zhang, Min; Iwanaga, Shiroh; Yuda, Masao; Tsuji, Moriya

    2017-01-01

    Objectives A CD1d-binding invariant natural killer T (iNKT)-cell stimulatory glycolipid, namely 7DW8–5, is shown to enhance the efficacy of radiation-attenuated sporozoites (RAS)-based malaria vaccine in mice. In the current study, we aim to determine whether 7DW8-5 can display a potent adjuvant effect in human immune system (HIS) mice. Methods HIS-A2/hCD1d mice, which possess both functional human iNKT cells and CD8+ T cells, were generated by the transduction of NSG mice with adeno-associated virus serotype 9 expressing genes that encode human CD1d molecules and HLA-A*0201, followed by the engraftment of human hematopoietic stem cells. The magnitudes of human iNKT-cell response against 7DW8-5 and HLA-A*0201-restricted human CD8+ T-cell response against a human malaria antigen in HIS-A2/hCD1d mice were determined by using human CD1d tetramer and human HLA-A*0201 tetramer, respectively. Results We found that 7DW8-5 stimulates human iNKT cells in HIS-A2/hCD1d mice, as well as those derived from HIS-A2/hCD1d mice in vitro. We also found that 7DW8-5 significantly increases the level of a human malarial antigen-specific HLA-A*0201-restricted human CD8+ T-cell response in HIS-A2/hCD1d mice. Conclusions Our study indicates that 7DW8-5 can display a potent adjuvant effect on RAS vaccine-induced anti-malarial immunity by augmenting malaria-specific human CD8+ T-cell response. PMID:27801602

  6. A potent adjuvant effect of a CD1d-binding NKT cell ligand in human immune system mice.

    PubMed

    Li, Xiangming; Huang, Jing; Kaneko, Izumi; Zhang, Min; Iwanaga, Shiroh; Yuda, Masao; Tsuji, Moriya

    2017-01-01

    A CD1d-binding invariant natural killer T (iNKT)-cell stimulatory glycolipid, namely 7DW8-5, is shown to enhance the efficacy of radiation-attenuated sporozoites (RAS)-based malaria vaccine in mice. In the current study, we aim to determine whether 7DW8-5 can display a potent adjuvant effect in human immune system (HIS) mice. HIS-A2/hCD1d mice, which possess both functional human iNKT cells and CD8+ T cells, were generated by the transduction of NSG mice with adeno-associated virus serotype 9 expressing genes that encode human CD1d molecules and HLA-A*0201, followed by the engraftment of human hematopoietic stem cells. The magnitudes of human iNKT-cell response against 7DW8-5 and HLA-A*0201-restricted human CD8+ T-cell response against a human malaria antigen in HIS-A2/hCD1d mice were determined by using human CD1d tetramer and human HLA-A*0201 tetramer, respectively. We found that 7DW8-5 stimulates human iNKT cells in HIS-A2/hCD1d mice, as well as those derived from HIS-A2/hCD1d mice in vitro. We also found that 7DW8-5 significantly increases the level of a human malarial antigen-specific HLA-A*0201-restricted human CD8+ T-cell response in HIS-A2/hCD1d mice. Our study indicates that 7DW8-5 can display a potent adjuvant effect on RAS vaccine-induced anti-malarial immunity by augmenting malaria-specific human CD8+ T-cell response.

  7. Excess adenosine in murine penile erectile tissues contributes to priapism via A2B adenosine receptor signaling

    PubMed Central

    Mi, Tiejuan; Abbasi, Shahrzad; Zhang, Hong; Uray, Karen; Chunn, Janci L.; Xia, Ling Wei; Molina, Jose G.; Weisbrodt, Norman W.; Kellems, Rodney E.; Blackburn, Michael R.; Xia, Yang

    2008-01-01

    Priapism, abnormally prolonged penile erection in the absence of sexual excitation, is associated with ischemia-mediated erectile tissue damage and subsequent erectile dysfunction. It is common among males with sickle cell disease (SCD), and SCD transgenic mice are an accepted model of the disorder. Current strategies to manage priapism suffer from a poor fundamental understanding of the molecular mechanisms underlying the disorder. Here we report that mice lacking adenosine deaminase (ADA), an enzyme necessary for the breakdown of adenosine, displayed unexpected priapic activity. ADA enzyme therapy successfully corrected the priapic activity both in vivo and in vitro, suggesting that it was dependent on elevated adenosine levels. Further genetic and pharmacologic evidence demonstrated that A2B adenosine receptor–mediated (A2BR-mediated) cAMP and cGMP induction was required for elevated adenosine–induced prolonged penile erection. Finally, priapic activity in SCD transgenic mice was also caused by elevated adenosine levels and A2BR activation. Thus, we have shown that excessive adenosine accumulation in the penis contributes to priapism through increased A2BR signaling in both Ada–/– and SCD transgenic mice. These findings provide insight regarding the molecular basis of priapism and suggest that strategies to either reduce adenosine or block A2BR activation may prove beneficial in the treatment of this disorder. PMID:18340377

  8. Probabilistic numerical discrimination in mice.

    PubMed

    Berkay, Dilara; Çavdaroğlu, Bilgehan; Balcı, Fuat

    2016-03-01

    Previous studies showed that both human and non-human animals can discriminate between different quantities (i.e., time intervals, numerosities) with a limited level of precision due to their endogenous/representational uncertainty. In addition, other studies have shown that subjects can modulate their temporal categorization responses adaptively by incorporating information gathered regarding probabilistic contingencies into their time-based decisions. Despite the psychophysical similarities between the interval timing and nonverbal counting functions, the sensitivity of count-based decisions to probabilistic information remains an unanswered question. In the current study, we investigated whether exogenous probabilistic information can be integrated into numerosity-based judgments by mice. In the task employed in this study, reward was presented either after few (i.e., 10) or many (i.e., 20) lever presses, the last of which had to be emitted on the lever associated with the corresponding trial type. In order to investigate the effect of probabilistic information on performance in this task, we manipulated the relative frequency of different trial types across different experimental conditions. We evaluated the behavioral performance of the animals under models that differed in terms of their assumptions regarding the cost of responding (e.g., logarithmically increasing vs. no response cost). Our results showed for the first time that mice could adaptively modulate their count-based decisions based on the experienced probabilistic contingencies in directions predicted by optimality.

  9. Mice embryology: a microscopic overview.

    PubMed

    Salvadori, Maria Letícia Baptista; Lessa, Thais Borges; Russo, Fabiele Baldino; Fernandes, Renata Avancini; Kfoury, José Roberto; Braga, Patricia Cristina Baleeiro Beltrão; Miglino, Maria Angélica

    2012-10-01

    In this work, we studied the embryology of mice of 12, 14, and 18 days of gestation by gross observation, light microscopy, and scanning electron microscopy. Grossly, the embryos of 12 days were observed in C-shaped region of the brain, eye pigmentation of the retina, first, second, and third pharyngeal arches gill pit nasal region on the fourth ventricle brain, cervical curvature, heart, liver, limb bud thoracic, spinal cord, tail, umbilical cord, and place of the mesonephric ridge. Microscopically, the liver, cardiovascular system and spinal cord were observed. In the embryo of 14 days, we observed structures that make up the liver and heart. At 18 days of gestation fetuses, it was noted the presence of eyes, mouth, and nose in the cephalic region, chest and pelvic region with the presence of well-developed limbs, umbilical cord, and placenta. Scanning electron microscopy in 18 days of gestation fetuses evidenced head, eyes closed eyelids, nose, vibrissae, forelimb, heart, lung, kidney, liver, small bowel, diaphragm, and part of the spine. The results obtained in this work describe the internal and external morphology of mice, provided by an integration of techniques and review of the morphological knowledge of the embryonic development of this species, as this animal is of great importance to scientific studies. Copyright © 2012 Wiley Periodicals, Inc.

  10. Adenosine receptor A2b on hematopoietic cells mediates LPS-induced migration of PMNs into the lung interstitium.

    PubMed

    Konrad, Franziska M; Witte, Esther; Vollmer, Irene; Stark, Stefanie; Reutershan, Jörg

    2012-09-01

    Uncontrolled transmigration of polymorphonuclear leukocytes (PMNs) into the different compartments of the lungs (intravascular, interstitial, alveolar) is a critical event in the early stage of acute lung injury and acute respiratory distress syndrome. Adenosine receptor A(2b) is highly expressed in the inflamed lungs and has been suggested to mediate cell trafficking. In a murine model of LPS-induced lung inflammation, we investigated the role of A(2b) on migration of PMNs into the different compartments of the lung. In A(2b)(-/-) mice, LPS-induced accumulation of PMNs was significantly higher in the interstitium, but not in the alveolar space. In addition, pulmonary clearance of PMNs was delayed in A(2b)(-/-) mice. Using chimeric mice, we identified A(2b) on hematopoietic cells as crucial for PMN migration. A(2b) did not affect the release of relevant chemokines into the alveolar space. LPS-induced microvascular permeability was under the control of A(2b) on both hematopoietic and nonhematopoietic cells. Activation of A(2b) on endothelial cells also reduced formation of LPS-induced stress fibers, highlighting its role for endothelial integrity. A specific A(2b) agonist (BAY 60-6583) was effective in decreasing PMN migration into the lung interstitium and microvascular permeability. In addition, in vitro transmigration of human PMNs through a layer of human endothelial or epithelial cells was A(2b) dependent. Activation of A(2b) on human PMNs reduced oxidative burst activity. Together, our results demonstrate anti-inflammatory effects of A(2b) on two major characteristics of acute lung injury, with a distinct role of hematopoietic A(2b) for cell trafficking and endothelial A(2b) for microvascular permeability.

  11. Assessment of bacterial contamination of drinking water provided to mice.

    PubMed

    Haist, Carrie; Cadillac, Joan; Dysko, Robert

    2004-11-01

    The objective of this study was to evaluate whether an 240-ml water bottle provided to individually housed mice would remain potable for a 2-week interval (based on absence of coliforms). The study used inbred C57BL/6 mice and CB6F1 x C3D2F1 hybrid mice. Test groups were assigned to minimize the variables of strain, caging type (non-ventilated static versus ventilated) and building location. A 3-cc sample of drinking water was removed aseptically from the bottles and vacuum-filtered using a 250-ml filter funnel with a 0.45-mum pore size. The membrane filter was removed using sterile forceps and placed on a blood agar plate for 10 min. The plate was streaked and incubated at 37 degrees C for 5 days. The plates were observed daily, and if growth had occurred, further testing was done to determine specific organisms. Of the 148 samples only 23 had any bacterial growth. Typical bacteria were unspeciated gram-positive bacilli and Staphylococcus, Micrococcus, Streptococcus, and Pantoea species. The absence of coliforms and low percentage of bacterial contamination suggest that drinking water will remain potable for 2 weeks when supplied to an individual mouse.

  12. Feasibility of Using Rice Hulls as Bedding for Laboratory Mice

    PubMed Central

    Carbone, Elizabeth T; Kass, Philip H; Evans, Kristin D

    2016-01-01

    Factors that are considered when selecting laboratory mouse bedding include animal health and comfort, cost, effects on personnel, and bioactive properties. Corncob is economical and facilitates low intracage ammonia but has undesirable influences on some endocrine studies. Rice hulls are an economical material that has not been well characterized as a bedding substrate. In this pilot study, we compared various aspects of bedding performance of rice hulls and other materials. On a per-volume basis, rice hulls were less absorbent than was corncob bedding. Rice hulls had higher odds than did corncob or reclaimed wood pulp of having moisture present at the bedding surface. The results of the absorbency tests coupled with the results of preliminary monitoring of intracage ammonia raised concern about the ability of rice hulls to control ammonia levels sufficiently in cages with high occupancy. However, ammonia was negligible when cages contained 5 young adult female mice. The relative expression of 3 cytochrome p450 genes was compared among mice housed on rice hulls, corncob, reclaimed wood pulp, or pine shavings. The expression of Cyp1a2 was 1.7 times higher in the livers of mice housed on rice hulls than on pine shavings, but other differences were not statistically significant. This study provides information on the merits of rice hulls as laboratory mouse bedding. Their relatively poor moisture control is a major disadvantage that might preclude their widespread use. PMID:27177559

  13. Euthanasia of neonatal mice with carbon dioxide

    USGS Publications Warehouse

    Pritchett, K.; Corrow, D.; Stockwell, J.; Smith, A.

    2005-01-01

    Exposure to carbon dioxide (CO2) is the most prevalent method used to euthanize rodents in biomedical research. The purpose of this study was to determine the time of CO2 exposure required to euthanize neonatal mice (0 to 10 days old). Multiple groups of mice were exposed to 100% CO 2 for time periods between 5 and 60 min. Mice were placed in room air for 10 or 20 min after CO2 exposure, to allow for the chance of recovery. If mice recovered at one time point, a longer exposure was examined. Inbred and outbred mice were compared. Results of the study indicated that time to death varied with the age of the animals and could be as long as 50 min on the day of birth and differed between inbred and outbred mice. Institutions euthanizing neonatal mice with CO2 may wish to adjust their CO 2 exposure time periods according the age of the mice and their genetic background. Copyright 2005 by the American Association for Laboratory Animal Science.

  14. Physical Exercise Preserves Adult Visual Plasticity in Mice and Restores it after a Stroke in the Somatosensory Cortex

    PubMed Central

    Kalogeraki, Evgenia; Pielecka-Fortuna, Justyna; Hüppe, Janika M.; Löwel, Siegrid

    2016-01-01

    The primary visual cortex (V1) is widely used to study brain plasticity, which is not only crucial for normal brain function, such as learning and memory, but also for recovery after brain injuries such as stroke. In standard cage (SC) raised mice, experience-dependent ocular dominance (OD) plasticity in V1 declines with age and is compromised by a lesion in adjacent and distant cortical regions. In contrast, mice raised in an enriched environment (EE), exhibit lifelong OD plasticity and are protected from losing OD plasticity after a stroke-lesion in the somatosensory cortex. Since SC mice with an access to a running wheel (RW) displayed preserved OD plasticity during aging, we investigated whether physical exercise might also provide a plasticity promoting effect after a cortical stroke. To this end, we tested if adult RW-raised mice preserved OD plasticity after stroke and also if short-term running after stroke restored OD plasticity to SC mice. Indeed, unlike mice without a RW, adult RW mice continued to show OD plasticity even after stroke, and a 2 weeks RW experience after stroke already restored lost OD plasticity. Additionally, the experience-enabled increase of the spatial frequency and contrast threshold of the optomotor reflex of the open eye, normally lost after a stroke, was restored in both groups of RW mice. Our data suggest that physical exercise alone can not only preserve visual plasticity into old age, but also restore it after a cortical stroke. PMID:27708575

  15. Sin Nombre virus shedding patterns in naturally infected deer mice (Peromyscus maniculatus) in relation to duration of infection.

    PubMed

    Safronetz, David; Drebot, Michael A; Artsob, Harvey; Cote, Tyler; Makowski, Kai; Lindsay, L Robbin

    2008-01-01

    A 2-year capture-mark-recapture study was conducted in southern Manitoba, Canada, to test for an association between the duration of Sin Nombre virus (SNV) infection in deer mice (Peromyscus maniculatus) and virus shedding. Hantavirus-specific IgG antibodies were detected in 22.2% of captured deer mice, and recently infected deer mice were identified based on the detection of low-avidity IgG antibodies. SNV RNA was detected in blood samples from the majority of seropositive deer mice with no significant difference in the association of SNV RNA between the low- and high-avidity groups (57.8% and 52.1%, respectively). A small subset of seropositive mice (11.6%) had detectable SNV RNA in oropharyngeal fluids (OPF) or urine. A greater proportion of deer mice with low-avidity antibodies had SNV RNA in OPF or urine compared with rodents with high-avidity antibodies (21% versus 6.8%, respectively). This is the first study of naturally infected deer mice to provide evidence that recently infected mice are more likely to shed SNV and thus might represent a greater risk of human infection.

  16. Ecto-5′-Nucleotidase (CD73)-Mediated Formation of Adenosine Is Critical for the Striatal Adenosine A2A Receptor Functions

    PubMed Central

    Augusto, Elisabete; Matos, Marco; Sévigny, Jean; El-Tayeb, Ali; Bynoe, Margaret S.; Müller, Christa E.

    2013-01-01

    Adenosine is a neuromodulator acting through inhibitory A1 receptors (A1Rs) and facilitatory A2ARs, which have similar affinities for adenosine. It has been shown that the activity of intracellular adenosine kinase preferentially controls the activation of A1Rs, but the source of the adenosine activating A2ARs is unknown. We now show that ecto-5′-nucleotidase (CD73), the major enzyme able to convert extracellular AMP into adenosine, colocalizes with A2ARs in the basal ganglia. In addition to astrocytes, striatal CD73 is prominently localized to postsynaptic sites. Notably, CD73 coimmunoprecipitated with A2ARs and proximity ligation assays confirmed the close proximity of CD73 and A2ARs in the striatum. Accordingly, the cAMP formation in synaptosomes as well as the hypolocomotion induced by a novel A2AR prodrug that requires CD73 metabolization to activate A2ARs were observed in wild-type mice, but not in CD73 knock-out (KO) mice or A2AR KO mice. Moreover, CD73 KO mice displayed increased working memory performance and a blunted amphetamine-induced sensitization, mimicking the phenotype of global or forebrain-A2AR KO mice, as well as upon pharmacological A2AR blockade. These results show that CD73-mediated formation of extracellular adenosine is responsible for the activation of striatal A2AR function. This study points to CD73 as a new target that can fine-tune A2AR activity, and a novel therapeutic target to manipulate A2AR-mediated control of striatal function and neurodegeneration. PMID:23843511

  17. Development of diabetic nephropathy in nude mice.

    PubMed

    Lin, S; Xu, P C; Huang, Q E; Jia, J Y; Jia, Z H; Wei, L; Zheng, Z F; Shang, W Y

    2013-12-01

    Immune dysfunction is very common in diabetes mellitus (DM). However, there is no evidence whether such immune dysfunction can influence the development of DM, especially the development of diabetic nephropathy (DN). To investigate the influence of absence of T cells on DN. Balb/c nude mice and Balb/c wild-type nude (WT) mice were injected with streptozotocin (STZ). Serum tumor necrosis factor α (TNF-α), blood glucose, body weight, urine albumin/creatinine ratio and rate of kidney weight to body weight (KW/BW) were measured. After modeling, there was no difference of blood glucose level between nude mice and WT mice except at week 2 (28.3 ± 4.9 mmol/l vs 23.1 ± 3.9 mmol/l, p<0.01). At week 4, the serum TNF- α level of nude mice got to 175.08 ± 46.03 pg/ml (p<0.05, compared with baseline level 80.19 ± 8.46 pg/ml), whereas the TNF- α levels of WT mice was stable. At week 4, the body weight of nude mice was lower than that of WT mice (14.7 ± 3.15 g vs 17.97 ± 2.85 g, p<0.05); the urine albumin/creatinine ratio (Alb/Cr) of nude mice was higher than that of WT mice (50.96 ± 5.57 mg/mmol vs 41.09 ± 5.79 mg/mmol, p<0.05); the kidney weight to body weight of nude mice was higher than that of WT mice (0.01352 ± 0.00163 vs 0.01173 ± 0.00131, p<0.05). Correlation analysis showed urine Alb/Cr positively correlated with serum TNF-α level at week 4 (r = 0.588, p<0.01). At week 4, the increase of type IV collagen in the glomeruli was more prominent in diabetic nude mice than in diabetic WT mice (p<0.05). Absence of T cells in DM might influence the development of DN.

  18. Pion contamination in the MICE muon beam

    NASA Astrophysics Data System (ADS)

    Adams, D.; Alekou, A.; Apollonio, M.; Asfandiyarov, R.; Barber, G.; Barclay, P.; de Bari, A.; Bayes, R.; Bayliss, V.; Bertoni, R.; Blackmore, V. J.; Blondel, A.; Blot, S.; Bogomilov, M.; Bonesini, M.; Booth, C. N.; Bowring, D.; Boyd, S.; Brashaw, T. W.; Bravar, U.; Bross, A. D.; Capponi, M.; Carlisle, T.; Cecchet, G.; Charnley, C.; Chignoli, F.; Cline, D.; Cobb, J. H.; Colling, G.; Collomb, N.; Coney, L.; Cooke, P.; Courthold, M.; Cremaldi, L. M.; DeMello, A.; Dick, A.; Dobbs, A.; Dornan, P.; Drews, M.; Drielsma, F.; Filthaut, F.; Fitzpatrick, T.; Franchini, P.; Francis, V.; Fry, L.; Gallagher, A.; Gamet, R.; Gardener, R.; Gourlay, S.; Grant, A.; Greis, J. R.; Griffiths, S.; Hanlet, P.; Hansen, O. M.; Hanson, G. G.; Hart, T. L.; Hartnett, T.; Hayler, T.; Heidt, C.; Hills, M.; Hodgson, P.; Hunt, C.; Iaciofano, A.; Ishimoto, S.; Kafka, G.; Kaplan, D. M.; Karadzhov, Y.; Kim, Y. K.; Kuno, Y.; Kyberd, P.; Lagrange, J.-B.; Langlands, J.; Lau, W.; Leonova, M.; Li, D.; Lintern, A.; Littlefield, M.; Long, K.; Luo, T.; Macwaters, C.; Martlew, B.; Martyniak, J.; Mazza, R.; Middleton, S.; Moretti, A.; Moss, A.; Muir, A.; Mullacrane, I.; Nebrensky, J. J.; Neuffer, D.; Nichols, A.; Nicholson, R.; Nugent, J. C.; Oates, A.; Onel, Y.; Orestano, D.; Overton, E.; Owens, P.; Palladino, V.; Pasternak, J.; Pastore, F.; Pidcott, C.; Popovic, M.; Preece, R.; Prestemon, S.; Rajaram, D.; Ramberger, S.; Rayner, M. A.; Ricciardi, S.; Roberts, T. J.; Robinson, M.; Rogers, C.; Ronald, K.; Rubinov, P.; Rucinski, P.; Sakamato, H.; Sanders, D. A.; Santos, E.; Savidge, T.; Smith, P. J.; Snopok, P.; Soler, F. J. P.; Speirs, D.; Stanley, T.; Stokes, G.; Summers, D. J.; Tarrant, J.; Taylor, I.; Tortora, L.; Torun, Y.; Tsenov, R.; Tunnell, C. D.; Uchida, M. A.; Vankova-Kirilova, G.; Virostek, S.; Vretenar, M.; Warburton, P.; Watson, S.; White, C.; Whyte, C. G.; Wilson, A.; Winter, M.; Yang, X.; Young, A.; Zisman, M.

    2016-03-01

    The international Muon Ionization Cooling Experiment (MICE) will perform a systematic investigation of ionization cooling with muon beams of momentum between 140 and 240 MeV/c at the Rutherford Appleton Laboratory ISIS facility. The measurement of ionization cooling in MICE relies on the selection of a pure sample of muons that traverse the experiment. To make this selection, the MICE Muon Beam is designed to deliver a beam of muons with less than ~1% contamination. To make the final muon selection, MICE employs a particle-identification (PID) system upstream and downstream of the cooling cell. The PID system includes time-of-flight hodoscopes, threshold-Cherenkov counters and calorimetry. The upper limit for the pion contamination measured in this paper is fπ < 1.4% at 90% C.L., including systematic uncertainties. Therefore, the MICE Muon Beam is able to meet the stringent pion-contamination requirements of the study of ionization cooling.

  19. Localized tetanus in immunized mice.

    PubMed

    Fishman, Paul S; Parks, Deborah A; Bowen, Thomas; Matthews, Christopher C

    2009-07-01

    The capacity of tetanus toxin to enhance motor neuron excitability has suggested its potential use as a therapeutic. Widespread active vaccination against tetanus in all developed countries is considered the major obstacle to clinical use of the toxin. We wished to determine the response to localized intramuscular injection of tetanus toxin in both passively and actively immunized animals as an initial exploration into the possible use of tetanus toxin as a clinical therapeutic. Unvaccinated mice (n=18) underwent intramuscular injection of tetanus toxin into the gastrocnemius muscle (0.2 ng, 1 ng, 5 ng). All animals in the lowest dose group developed only local tetanus of the injected limb of at least 2 weeks duration, while all animals in the higher dose groups also rapidly developed generalized tetanus and were euthanized. Another group of mice (n=20) received anti-tetanus immunoglobulin (20-40 IU) at the time of toxin injection. These animals although dramatically resistant to the toxin developed predominantly local tetanus for over one month at doses of 2.5 microg and 5.0 microg. A third group of mice (n=30) underwent active vaccination with tetanus toxoid to induce protective anti-tetanus immunity and then was challenged with high dose toxin injection (5 ng, 50 ng, 0.5 microg, 1.25 microg, 2.5 microg, or 5 microg). All animals developed local tetanus in the injected limb at a dose of at least 0.5 microg. The severity and duration of local tetanus was generally related to dose, but was more variable in the actively vaccinated group than in the naive or passively immunized animals. Response to the toxin over the first few days was predictive of both the duration and maximal severity of the motor response. Although vaccination dramatically increases resistance to tetanus toxin, by virtue of its extremely high potency, the toxin can produce prolonged localized tetanus even in vaccinated animals with relatively small amounts of protein. These results suggest the

  20. Muscle Structure Influences Utrophin Expression in mdx Mice

    PubMed Central

    Banks, Glen B.; Combs, Ariana C.; Odom, Guy L.; Bloch, Robert J.; Chamberlain, Jeffrey S.

    2014-01-01

    Duchenne muscular dystrophy (DMD) is a severe muscle wasting disorder caused by mutations in the dystrophin gene. To examine the influence of muscle structure on the pathogenesis of DMD we generated mdx4cv:desmin double knockout (dko) mice. The dko male mice died of apparent cardiorespiratory failure at a median age of 76 days compared to 609 days for the desmin−/− mice. An ∼2.5 fold increase in utrophin expression in the dko skeletal muscles prevented necrosis in ∼91% of 1a, 2a and 2d/x fiber-types. In contrast, utrophin expression was reduced in the extrasynaptic sarcolemma of the dko fast 2b fibers leading to increased membrane fragility and dystrophic pathology. Despite lacking extrasynaptic utrophin, the dko fast 2b fibers were less dystrophic than the mdx4cv fast 2b fibers suggesting utrophin-independent mechanisms were also contributing to the reduced dystrophic pathology. We found no overt change in the regenerative capacity of muscle stem cells when comparing the wild-type, desmin−/−, mdx4cv and dko gastrocnemius muscles injured with notexin. Utrophin could form costameric striations with α-sarcomeric actin in the dko to maintain the integrity of the membrane, but the lack of restoration of the NODS (nNOS, α-dystrobrevin 1 and 2, α1-syntrophin) complex and desmin coincided with profound changes to the sarcomere alignment in the diaphragm, deposition of collagen between the myofibers, and impaired diaphragm function. We conclude that the dko mice may provide new insights into the structural mechanisms that influence endogenous utrophin expression that are pertinent for developing a therapy for DMD. PMID:24922526

  1. Adenosine Transporter ENT1 Regulates the Acquisition of Goal-Directed Behavior and Ethanol Drinking Through A2A Receptor in the Dorsomedial Striatum

    PubMed Central

    Nam, Hyung Wook; Hinton, David J.; Kang, Na Young; Kim, Taehyun; Lee, Moonnoh R.; Oliveros, Alfredo; Adams, Chelsea; Ruby, Christina L.; Choi, Doo-Sup

    2013-01-01

    Adenosine signaling has been implicated in the pathophysiology of many psychiatric disorders including alcoholism. Striatal adenosine A2A receptors (A2AR) play an essential role in both ethanol drinking and the shift from goal-directed action to habitual behavior. However, direct evidence for a role of striatal A2AR signaling in ethanol drinking and habit development has not been established. Here, we identified that decreased A2AR-mediated CREB activity in the dorsomedial striatum (DMS) enhanced initial behavioral acquisition of goal-directed behaviors and the vulnerability to progress to excessive ethanol drinking during operant conditioning in mice lacking ethanol-sensitive adenosine transporter ENT1 (ENT1−/−). Utilizing mice expressing β-galactosidase (lacZ) under the control of seven-repeated CRE sites in both genotypes (CRE-lacZ/ENT1+/+ mice and CRE-lacZ/ENT1−/− mice) as well as dnCREB (dominant negative form of CREB), we found that reduced CREB activity in the DMS is causally associated with decreased A2AR signaling and increased goal-directed ethanol drinking. Finally, we demonstrated that A2AR antagonist (ZM241385) dampened PKA-activity mediated signaling in the DMS and promoted excessive ethanol drinking in ENT1+/+ mice, but not in ENT1−/− mice. Taken together, our studies indicate that A2AR-mediated CREB signaling in the DMS is a key determinant to enhance the development of goal-directed ethanol drinking in mice. PMID:23467349

  2. Cutaneous transcriptome analysis in NIH hairless mice.

    PubMed

    Ji, Zhong-Hao; Chen, Jian; Gao, Wei; Zhang, Jin-Yu; Quan, Fu-Shi; Hu, Jin-Ping; Yuan, Bao; Ren, Wen-Zhi

    2017-01-01

    Mice with spontaneous coat mutations are ideal animal models for studying skin development and tumorigenesis. In this study, skin hair growth cycle abnormalities were examined in NIH hairless mice 42 days after birth (P42) by using hematoxylin-eosin (H&E) staining. To examine the gene expression patterns in the skin of mutant mice, the dorsal skin of P42 female NIH mice and NIH hairless mice was sequenced by RNA-Seq, and 5,068 differentially expressed genes (DEGs) were identified (false discovery rate [FDR] ≥ 2, P < 0.05). A pathway analysis showed that basal cell carcinoma, the cell cycle and the Hippo, Hedgehog and Wnt signaling pathways were up-regulated in NIH hairless mice. Previous studies have shown that these pathways are closely associated with cell proliferation, cell cycle, organ size and cancer development. In contrast, signal transduction, bacterial and parasitic infection, and receptor-mediated pathways, including calcium signaling, were down-regulated in NIH hairless mice. A gene interaction network analysis was performed to identify genes related to hair follicle development. To verify the reliability of the RNA-Seq results, we used q-PCR to analyze 12 key genes identified from the gene interaction network analysis, including eight down-regulated and four up-regulated genes, and the results confirmed the reliability of the RNA-Seq results. Finally, we constructed the differential gene expression profiles of mutant mice by RNA-Seq. NIH hairless mice exhibited abnormalities in hair development and immune-related pathways. Pik3r1 and Pik3r3 were identified as key genes, laying the foundation for additional in-depth studies of hairless mice.

  3. Light/dark transition test for mice.

    PubMed

    Takao, Keizo; Miyakawa, Tsuyoshi

    2006-11-13

    Although all of the mouse genome sequences have been determined, we do not yet know the functions of most of these genes. Gene-targeting techniques, however, can be used to delete or manipulate a specific gene in mice. The influence of a given gene on a specific behavior can then be determined by conducting behavioral analyses of the mutant mice. As a test for behavioral phenotyping of mutant mice, the light/dark transition test is one of the most widely used tests to measure anxiety-like behavior in mice. The test is based on the natural aversion of mice to brightly illuminated areas and on their spontaneous exploratory behavior in novel environments. The test is sensitive to anxiolytic drug treatment. The apparatus consists of a dark chamber and a brightly illuminated chamber. Mice are allowed to move freely between the two chambers. The number of entries into the bright chamber and the duration of time spent there are indices of bright-space anxiety in mice. To obtain phenotyping results of a strain of mutant mice that can be readily reproduced and compared with those of other mutants, the behavioral test methods should be as identical as possible between laboratories. The procedural differences that exist between laboratories, however, make it difficult to replicate or compare the results among laboratories. Here, we present our protocol for the light/dark transition test as a movie so that the details of the protocol can be demonstrated. In our laboratory, we have assessed more than 60 strains of mutant mice using the protocol shown in the movie. Those data will be disclosed as a part of a public database that we are now constructing. Visualization of the protocol will facilitate understanding of the details of the entire experimental procedure, allowing for standardization of the protocols used across laboratories and comparisons of the behavioral phenotypes of various strains of mutant mice assessed using this test.

  4. Protective immunity provided by HLA-A2 epitopes for fusion and hemagglutinin proteins of measles virus

    SciTech Connect

    Oh, Sang Kon; Stegman, Brian; Pendleton, C. David

    2006-09-01

    Natural infection and vaccination with a live-attenuated measles virus (MV) induce CD8{sup +} T-cell-mediated immune responses that may play a central role in controlling MV infection. In this study, we show that newly identified human HLA-A2 epitopes from MV hemagglutinin (H) and fusion (F) proteins induced protective immunity in HLA-A2 transgenic mice challenged with recombinant vaccinia viruses expressing F or H protein. HLA-A2 epitopes were predicted and synthesized. Five and four peptides from H and F, respectively, bound to HLA-A2 molecules in a T2-binding assay, and four from H and two from F could induce peptide-specific CD8{sup +} T cellmore » responses in HLA-A2 transgenic mice. Further experiments proved that three peptides from H (H9-567, H10-250, and H10-516) and one from F protein (F9-57) were endogenously processed and presented on HLA-A2 molecules. All peptides tested in this study are common to 5 different strains of MV including Edmonston. In both A2K{sup b} and HHD-2 mice, the identified peptide epitopes induced protective immunity against recombinant vaccinia viruses expressing H or F. Because F and H proteins induce neutralizing antibodies, they are major components of new vaccine strategies, and therefore data from this study will contribute to the development of new vaccines against MV infection.« less

  5. Sterol 27-hydroxylase gene dosage and the antiatherosclerotic effect of Rifampicin in mice

    PubMed Central

    Zurkinden, Line; Sviridov, Dmitri; Vogt, Bruno

    2017-01-01

    Sterol 27-hydroxylase (CYP27A1) catalyzes the hydroxylation of cholesterol to 27-hydroxycholesterol (27-OHC) and regulates cholesterol homeostasis. In Cyp27a1/ Apolipoprotein E (ApoE) double knockout (KO) mice fed with Western diet (WD), the atherosclerotic phenotype found in ApoE KO mice was reversed. As protective mechanism, up-regulation of Cyp3a11 and Cyp7a1 was proposed. Cyp27a1 heterozygote/ApoE KO (het) mice, with reduced Cyp27a1 expression and normal levels of Cyp7a1 and Cyp3a11, developed more severe lesions than ApoE KO mice. To analyze the contribution of Cyp3a11 to the protection of atherosclerosis development, Cyp3a11 was induced by Rifampicin (RIF) in ApoE KO and het mice. Males were fed with WD and treated daily with RIF (10 mg/kg ip) or vehicle for 4 weeks. Atherosclerosis was quantified in the aortic valve. Plasma lipids and 27-hydroxycholesterol (27-OHC), expression of cytochromes P450 and genes involved in cholesterol transport and bile acids (BAs) signaling in liver and intestine, and intestinal cholesterol absorption were analyzed. RIF increased expression of hepatic but not intestinal Cyp3a11 4-fold in both genotypes. In ApoE KO mice treated with RIF, we found a 2-fold decrease in plasma cholesterol, and a 2-fold increase in high-density lipoprotein/low-density lipoprotein ratio and CY27A1 activity. Intestinal cholesterol absorption remained unchanged and atherosclerotic lesions decreased approximately 3-fold. In het mice, RIF had no effect on plasma lipids composition, CYP27A1 activity, and atherosclerotic plaque development, despite a reduction in cholesterol absorption. In conclusion, the antiatherogenic effect of Cyp3a11 induction by RIF was also dependent on Cyp27a1 expression. PMID:29191818

  6. Sterol 27-hydroxylase gene dosage and the antiatherosclerotic effect of Rifampicin in mice.

    PubMed

    Zurkinden, Line; Sviridov, Dmitri; Vogt, Bruno; Escher, Geneviève

    2018-02-28

    Sterol 27-hydroxylase (CYP27A1) catalyzes the hydroxylation of cholesterol to 27-hydroxycholesterol (27-OHC) and regulates cholesterol homeostasis. In Cyp27a1/ Apolipoprotein E ( ApoE ) double knockout (KO) mice fed with Western diet (WD), the atherosclerotic phenotype found in ApoE KO mice was reversed. As protective mechanism, up-regulation of Cyp3a11 and Cyp7a1 was proposed. Cyp27a1 heterozygote/ ApoE KO (het) mice, with reduced Cyp27a1 expression and normal levels of Cyp7a1 and Cyp3a11 , developed more severe lesions than ApoE KO mice. To analyze the contribution of Cyp3a11 to the protection of atherosclerosis development, Cyp3a11 was induced by Rifampicin (RIF) in ApoE KO and het mice. Males were fed with WD and treated daily with RIF (10 mg/kg ip) or vehicle for 4 weeks. Atherosclerosis was quantified in the aortic valve. Plasma lipids and 27-hydroxycholesterol (27-OHC), expression of cytochromes P450 and genes involved in cholesterol transport and bile acids (BAs) signaling in liver and intestine, and intestinal cholesterol absorption were analyzed. RIF increased expression of hepatic but not intestinal Cyp3a11 4-fold in both genotypes. In ApoE KO mice treated with RIF, we found a 2-fold decrease in plasma cholesterol, and a 2-fold increase in high-density lipoprotein/low-density lipoprotein ratio and CY27A1 activity. Intestinal cholesterol absorption remained unchanged and atherosclerotic lesions decreased approximately 3-fold. In het mice, RIF had no effect on plasma lipids composition, CYP27A1 activity, and atherosclerotic plaque development, despite a reduction in cholesterol absorption. In conclusion, the antiatherogenic effect of Cyp3a11 induction by RIF was also dependent on Cyp27a1 expression. © 2018 The Author(s).

  7. Primordial Germ Cells in Mice

    PubMed Central

    Saitou, Mitinori; Yamaji, Masashi

    2012-01-01

    Germ cell development creates totipotency through genetic as well as epigenetic regulation of the genome function. Primordial germ cells (PGCs) are the first germ cell population established during development and are immediate precursors for both the oocytes and spermatogonia. We here summarize recent findings regarding the mechanism of PGC development in mice. We focus on the transcriptional and signaling mechanism for PGC specification, potential pluripotency, and epigenetic reprogramming in PGCs and strategies for the reconstitution of germ cell development using pluripotent stem cells in culture. Continued studies on germ cell development may lead to the generation of totipotency in vitro, which should have a profound influence on biological science as well as on medicine. PMID:23125014

  8. Mobile optogenetic modules for mice

    NASA Astrophysics Data System (ADS)

    Rusakov, Konstantin; Radzewicz, Czesław; Czajkowski, Rafał; Konopka, Witold; Chilczuk, Joanna

    2017-08-01

    We present a set of novel optogenetic devices for mice freely moving in cages. The purpose of the devices is to stimulate specific brain regions using light. The devices we have constructed consist of an electrical connector, cannula and micro- LED chip operating at 470 nm as light source for delivering light into the stimulated region of the mouse brain. We have also demonstrated light conversion from 470 nm to 590 nm by applying a silicate orange phosphor directly to the LED chip. The measured conversion efficiency is approximately 80% for ZIP595I phosphor. We discuss the properties of various forms of implant needles with respect to the ease of LED attachment and experimental validation of the constructed optogenetic implants.

  9. Lecithin:Cholesterol Acyltransferase Deficiency Protects against Cholesterol-induced Hepatic Endoplasmic Reticulum Stress in Mice*

    PubMed Central

    Hager, Lauren; Li, Lixin; Pun, Henry; Liu, Lu; Hossain, Mohammad A.; Maguire, Graham F.; Naples, Mark; Baker, Chris; Magomedova, Lilia; Tam, Jonathan; Adeli, Khosrow; Cummins, Carolyn L.; Connelly, Philip W.; Ng, Dominic S.

    2012-01-01

    We recently reported that lecithin:cholesterol acyltransferase (LCAT) knock-out mice, particularly in the LDL receptor knock-out background, are hypersensitive to insulin and resistant to high fat diet-induced insulin resistance (IR) and obesity. We demonstrated that chow-fed Ldlr−/−xLcat+/+ mice have elevated hepatic endoplasmic reticulum (ER) stress, which promotes IR, compared with wild-type controls, and this effect is normalized in Ldlr−/−xLcat−/− mice. In the present study, we tested the hypothesis that hepatic ER cholesterol metabolism differentially regulates ER stress using these models. We observed that the Ldlr−/−xLcat+/+ mice accumulate excess hepatic total and ER cholesterol primarily attributed to increased reuptake of biliary cholesterol as we observed reduced biliary cholesterol in conjunction with decreased hepatic Abcg5/g8 mRNA, increased Npc1l1 mRNA, and decreased Hmgr mRNA and nuclear SREBP2 protein. Intestinal NPC1L1 protein was induced. Expression of these genes was reversed in the Ldlr−/−xLcat−/− mice, accounting for the normalization of total and ER cholesterol and ER stress. Upon feeding a 2% high cholesterol diet (HCD), Ldlr−/−xLcat−/− mice accumulated a similar amount of total hepatic cholesterol compared with the Ldlr−/−xLcat+/+ mice, but the hepatic ER cholesterol levels remained low in conjunction with being protected from HCD-induced ER stress and IR. Hepatic ER stress correlates strongly with hepatic ER free cholesterol but poorly with hepatic tissue free cholesterol. The unexpectedly low ER cholesterol seen in HCD-fed Ldlr−/−xLcat−/− mice was attributable to a coordinated marked up-regulation of ACAT2 and suppressed SREBP2 processing. Thus, factors influencing the accumulation of ER cholesterol may be important for the development of hepatic insulin resistance. PMID:22500017

  10. Social reward among juvenile mice

    PubMed Central

    Panksepp, J B; Lahvis, G P

    2007-01-01

    Mammalian social relationships, such as mother–offspring attachments and pair bonds, can directly affect reproductive output. However, conspecifics approach one another in a comparatively broad range of contexts, so conceivably there are motivations for social congregation other than those underlying reproduction, parental care or territoriality. Here, we show that reward mediated by social contact is a fundamental aspect of juvenile mouse sociality. Employing a novel social conditioned place preference (SCPP) procedure, we demonstrate that social proximity is rewarding for juvenile mice from three inbred strains (A/J, C57BL/6J and DBA/2J), while mice from a fourth strain (BALB/cJ) are much less responsive to social contact. Importantly, this strain-dependent difference was not related to phenotypic variability in exploratory behavior or contextual learning nor influenced by the genetic background associated with maternal care or social conditioning. Furthermore, the SCPP phenotype was expressed early in development (postnatal day 25) and did not require a specific sex composition within the conditioning group. Finally, SCPP responses resulted from an interaction between two specifiable processes: one component of the interaction facilitated approach toward environments that were associated with social salience, whereas a second component mediated avoidance of environmental cues that predicted social isolation. We have thus identified a genetically prescribed process that can attribute value onto conditions predicting a general form of social contact. To our knowledge, this is the first definitive evidence to show that genetic variation can influence a form of social valuation not directly related to a reproductive behavior. PMID:17212648

  11. 42 CFR 5a.2 - Applicability.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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  12. 42 CFR 5a.2 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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  13. 42 CFR 5a.2 - Applicability.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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  14. 42 CFR 5a.2 - Applicability.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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  15. 42 CFR 51a.2 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

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  16. 32 CFR 168a.2 - Applicability.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

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  17. 32 CFR 168a.2 - Applicability.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

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  18. 32 CFR 168a.2 - Applicability.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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  19. 32 CFR 168a.2 - Applicability.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

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  20. 32 CFR 168a.2 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

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  1. 42 CFR 5a.2 - Applicability.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Applicability. 5a.2 Section 5a.2 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS RURAL PHYSICIAN TRAINING GRANT PROGRAM § 5a.2 Applicability. This part applies to grants made under section 749B of the...