Science.gov

Sample records for a2ar ko mice

  1. 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

  2. Increased susceptibility of radiation-induced intestinal apoptosis in SMP30 KO mice.

    PubMed

    Goo, Moon-Jung; Park, Jin-Kyu; Hong, Il-Hwa; Kim, Ah-Young; Lee, Eun-Mi; Lee, Eun-Joo; Hwang, Meeyul; Jeong, Kyu-Shik

    2013-05-24

    Recently, senescence marker protein-30 (SMP30) knockout (KO) mice have been reported to be susceptible to apoptosis, however, the role of SMP30 has not been characterized in the small intestine. The aim of the present study is to investigate the role of SMP30 in the process of spontaneous and γ-radiation-induced apoptosis in mouse small intestine. Eight-week-old male wild-type (WT) mice and SMP30 KO mice were examined after exposure to 0, 1, 3, 5, and 9 Gy of γ-radiation. Apoptosis in the crypts of the small intestine increased in the 0 to 5 Gy radiated SMP30 KO and WT mice. Radiation-induced apoptosis and the BAX/Bcl-2 ratio in the SMP30 KO mice were significantly increased in comparison to each identically treated group of WT mice (p < 0.05). The levels of spontaneous apoptosis in both WT and KO mice were similar (p > 0.05), indicating that increased apoptosis of crypt cells of SMP30 KO by irradiation can be associated with SMP30 depletion. These results suggested that SMP30 might be involved in overriding the apoptotic homeostatic mechanism in response to DNA damage.

  3. Eplerenone-Resistant Salt-Sensitive Hypertension in Nedd4-2 C2 KO Mice.

    PubMed

    Kino, Tabito; Ishigami, Tomoaki; Murata, Tsumugi; Doi, Hiroshi; Nakashima-Sasaki, Rie; Chen, Lin; Sugiyama, Michiko; Azushima, Kengo; Wakui, Hiromichi; Minegishi, Shintaro; Tamura, Kouichi

    2017-06-11

    The epithelial sodium channel (ENaC) plays critical roles in maintaining fluid and electrolyte homeostasis and is located in the aldosterone-sensitive distal nephron (ASDN). We previously found that Nedd4-2 C2 knockout (KO) mice showed salt-sensitive hypertension with paradoxically enhanced ENaC gene expression in ASDN under high oral salt intake. Eplerenone (EPL), a selective aldosterone blocker, is a promising therapeutic option for resistant or/and salt-sensitive hypertension. We examined the effect of EPL on Nedd4-2 C2 KO mice with respect to blood pressure, metabolic parameters, and molecular level changes in ASDN under high oral salt intake. We found that EPL failed to reduce blood pressure in KO mice with high oral salt intake and upregulated ENaC expression in ASDN. Thus, salt-sensitive hypertension in Nedd4-2 C2 KO was EPL-resistant. Gene expression analyses of laser-captured specimens in ASDN suggested the presence of non-aldosterone-dependent activation of ENaC transcription in ASDN of Nedd4-2 C2 KO mice, which was abolished by amiloride treatment. Our results from Nedd4-2 C2 KO mice suggest that enhanced ENaC gene expression is critically involved in salt-sensitive hypertension under certain conditions of specific enzyme isoforms for their ubiquitination.

  4. Impaired memory of eyeblink conditioning in CaMKIV KO mice.

    PubMed

    Lee, Ka Hung; Chatila, Talal A; Ram, Rana A; Thompson, Richard F

    2009-04-01

    The calcium/calmodulin-dependent protein kinase type IV (CaMKIV) is highly expressed in cerebellar cortical granule cells and deep nuclear neurons in the cerebellum. It mediates the phosphorylation and activation of the cAMP-dependent response element binding protein (CREB). In several paradigms CREB-dependent transcription is required for cellular events underlying long-term memory processes. Also, CaMKIV deficiency results in impaired long-term depression (LTD) induction in cerebellar cortex. To investigate the function of CaMKIV in the cerebellum, Wild-type (WT) and CaMKIV KO mice were tested with delay eyeblink conditioning. KO and WT mice did not differ in acquisition, but the KO mice showed a significantly lower conditioned response (CR) percentage than the WT mice in the retention testing and retraining period. The CR peak latencies for the two groups did not differ in acquisition but were shorter for the KO mice in the testing period. No significant differences were found between KO and WT mice in spontaneous eyeblink activity, auditory brainstem response (ABR) amplitudes, and tail-flick latency. The results suggest an important role for CaMKIV in long-term memory in the cerebellum. (c) 2009 APA, all rights reserved.

  5. Enhanced urinary odor discrimination in female aromatase knockout (ArKO) mice

    PubMed Central

    Wesson, Daniel W.; Keller, Matthieu; Douhard, Quentin; Baum, Michael J.; Bakker, Julie

    2008-01-01

    We asked whether odor discrimination abilities are sexually dimorphic in mice and, if so, whether the perinatal actions of estradiol contribute to these sex differences. The ability to discriminate different types of urinary odors was compared in male and female wild-type (WT) subjects and in mice with a homozygous-null mutation of the estrogen synthetic enzyme, aromatase (aromatase knockout; ArKO). Olfactory discrimination was assessed in WT and ArKO male and female mice after they were gonadectomized in adulthood and subsequently treated with estradiol benzoate. A liquid olfactometer was used to assess food-motivated olfactory discrimination capacity. All animals eventually learned to distinguish between urinary odors collected from gonadally intact males and estrous females; however, WT males as well as ArKO mice of both sexes learned this discrimination significantly more rapidly than WT females. Similar group differences were obtained when mice discriminated between urinary odors collected from gonadally intact vs. castrated males or between two non-social odorants, amyl and butyl acetate. When subjects had to discriminate volatile urinary odors from ovariectomized female mice treated with estradiol sequenced with progesterone versus estradiol alone, ArKO females quickly acquired the task whereas WT males and females as well as ArKO males failed to do so. These results demonstrated a strong sex dimorphism in olfactory discrimination ability, with WT males performing better than females. Furthermore, female ArKO mice showed an enhanced ability to discriminate very similar urinary odorants, perhaps due to an increased sensitivity of the main olfactory nervous system to adult estradiol treatment as a result of perinatal estrogen deprivation. PMID:16448653

  6. Hearts of surviving MLP-KO mice show transient changes of intracellular calcium handling.

    PubMed

    Kemecsei, Péter; Miklós, Zsuzsanna; Bíró, Tamás; Marincsák, Rita; Tóth, Balázs I; Komlódi-Pásztor, Edina; Barnucz, Eniko; Mirk, Eva; Van der Vusse, Ger J; Ligeti, László; Ivanics, Tamás

    2010-09-01

    The muscle Lim protein knock-out (MLP-KO) mouse model is extensively used for studying the pathophysiology of dilated cardiomyopathy. However, explanation is lacking for the observed long survival of the diseased mice which develop until adulthood despite the gene defect, which theoretically predestines them to early death due to heart failure. We hypothesized that adaptive changes of cardiac intracellular calcium (Ca(i)(2+)) handling might explain the phenomenon. In order to study the progression of changes in cardiac function and Ca(i)(2+) cycling, myocardial Ca(i)(2+)-transients recorded by Indo-1 surface fluorometry were assessed with concomitant measurement of hemodynamic performance in isolated Langendorff-perfused hearts of 3- and 9-month old MLP-KO animals. Hearts were challenged with beta-agonist isoproterenol and the sarcoplasmic reticular Ca(2+)-ATPase (SERCA2a) inhibitor cyclopiazonic acid (CPA). Cardiac mRNA content and levels of key Ca(2+) handling proteins were also measured. A decline in lusitropic function was observed in 3-month old, but not in 9-month old MLP-KO mice under unchallenged conditions. beta-adrenergic responses to isoproterenol were similar in all the studied groups. The CPA induced an increase in end-diastolic Ca(i)(2+)-level and a decrease in Ca(2+)-sequestration capacity in 3-month old MLP-KO mice compared to age-matched controls. This unfavorable condition was absent at 9 months of age. SERCA2a expression was lower in 3-month old MLP-KO than in the corresponding controls and in 9-month old MLP-KO hearts. Our results show time-related recovery of hemodynamic function and an age-dependent compensatory upregulation of Ca(i)(2+) handling in hearts of MLP-KO mice, which most likely involve the normalization of the expression of SERCA2a in the affected hearts.

  7. Increased Adiposity, Dysregulated Glucose Metabolism and Systemic Inflammation in Galectin-3 KO Mice

    PubMed Central

    Pang, Jingbo; Rhodes, Davina H.; Pini, Maria; Akasheh, Rand T.; Castellanos, Karla J.; Cabay, Robert J.; Cooper, Dianne; Perretti, Mauro; Fantuzzi, Giamila

    2013-01-01

    Obesity and type 2 diabetes are associated with increased production of Galectin-3 (Gal-3), a protein that modulates inflammation and clearance of glucose adducts. We used Lean and Diet-induced Obese (DIO) WT and Gal-3 KO mice to investigate the role of Gal-3 in modulation of adiposity, glucose metabolism and inflammation. Deficiency of Gal-3 lead to age-dependent development of excess adiposity and systemic inflammation, as indicated by elevated production of acute-phase proteins, number of circulating pro-inflammatory Ly6Chigh monocytes and development of neutrophilia, microcytic anemia and thrombocytosis in 20-week-old Lean and DIO male Gal-3 KO mice. This was associated with impaired fasting glucose, heightened response to a glucose tolerance test and reduced adipose tissue expression of adiponectin, Gal-12, ATGL and PPARγ, in the presence of maintained insulin sensitivity and hepatic expression of gluconeogenic enzymes in 20-week-old Gal-3 KO mice compared to their diet-matched WT controls. Expression of PGC-1α and FGF-21 in the liver of Lean Gal-3 KO mice was comparable to that observed in DIO animals. Impaired fasting glucose and altered responsiveness to a glucose load preceded development of excess adiposity and systemic inflammation, as demonstrated in 12-week-old Gal-3 KO mice. Finally, a role for the microflora in mediating the fasting hyperglycemia, but not the excessive response to a glucose load, of 12-week-old Gal-3 KO mice was demonstrated by administration of antibiotics. In conclusion, Gal-3 is an important modulator of glucose metabolism, adiposity and inflammation. PMID:23451284

  8. High purity tocotrienols attenuate atherosclerotic lesion formation in apoE-KO mice.

    PubMed

    Shibata, Akira; Kobayashi, Teiko; Asai, Akira; Eitsuka, Takahiro; Oikawa, Shinichi; Miyazawa, Teruo; Nakagawa, Kiyotaka

    2017-10-01

    Previous studies have demonstrated that tocotrienol (T3) has antiatherogenic effects. However, the T3 preparations used in those studies contained considerable amounts of tocopherol (Toc), which might affect the biological activity of T3. There is little information on the effect of highly purified T3 on atherosclerosis formation. This study investigated the effect of high-purity T3 on atherosclerotic lesion formation and the underlying mechanisms. Male apolipoprotein E knockout (apoE-KO) mice were fed a cholesterol-containing diet either alone or supplemented with T3 concentrate (Toc-free T3) or with α-Toc for 12 weeks. ApoE-KO mice fed the 0.2% T3-supplemented diet showed reduced atherosclerotic lesion formation in the aortic root. The 0.2% T3 diet induced Slc27a1 and Ldlr gene expression levels in the liver, whereas the α-Toc-supplemented diet did not affect those expression levels. T3 was predominantly deposited in fat tissue in the T3 diet-fed mice, whereas α-Toc was preferentially accumulated in liver in the α-Toc diet-fed mice. Considered together, these data demonstrate that dietary T3 exerts anti-atherosclerotic effect in apoE-KO mice. The characteristic tissue distribution and biological effects of T3, that are substantially different from those of Toc, may contribute to the antiatherogenic properties of T3. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Amygdala Lesions Reduce Cataplexy in Orexin KO mice

    PubMed Central

    Burgess, C.R.; Oishi, Y.; Mochizuki, T.; Peever, J.H.; Scammell, T.E.

    2013-01-01

    Narcolepsy is characterized by excessive sleepiness and cataplexy, sudden episodes of muscle weakness during waking that are thought to be an intrusion of REM sleep muscle atonia into wakefulness. One of the most striking aspects of cataplexy is that it is often triggered by strong, generally positive emotions, but little is known about the neural pathways through which positive emotions trigger muscle atonia. We hypothesized that the amygdala is functionally important for cataplexy because the amygdala has a role in processing emotional stimuli and it contains neurons that are active during cataplexy. Using anterograde and retrograde tracing in mice, we found that GABAergic neurons in the central nucleus of the amygdala heavily innervate neurons that maintain waking muscle tone such as those in the ventrolateral periaqueductal grey, lateral pontine tegmentum, locus coeruleus, and dorsal raphe. We then found that bilateral, excitotoxic lesions of the amygdala markedly reduced cataplexy in orexin knockout mice, a model of narcolepsy. These lesions did not alter basic sleep/wake behavior, but substantially reduced the triggering of cataplexy. Lesions also reduced the cataplexy events triggered by conditions associated with high arousal and positive emotions (i.e., wheel running and chocolate). These observations demonstrate that the amygdala is a functionally important part of the circuitry underlying cataplexy and suggest that increased amygdala activity in response to emotional stimuli could directly trigger cataplexy by inhibiting brainstem regions that suppress muscle atonia. PMID:23739970

  10. Exaggerated phosphorylation of brain tau protein in CRH KO mice exposed to repeated immobilization stress.

    PubMed

    Kvetnansky, Richard; Novak, Petr; Vargovic, Peter; Lejavova, Katarina; Horvathova, Lubica; Ondicova, Katarina; Manz, George; Filipcik, Peter; Novak, Michal; Mravec, Boris

    2016-07-01

    Neuroendocrine and behavioral stress responses are orchestrated by corticotropin-releasing hormone (CRH) and norepinephrine (NE) synthesizing neurons. Recent findings indicate that stress may promote development of neurofibrillary pathology in Alzheimer's disease. Therefore, we investigated relationships among stress, tau protein phosphorylation, and brain NE using wild-type (WT) and CRH-knockout (CRH KO) mice. We assessed expression of phosphorylated tau (p-tau) at the PHF-1 epitope and NE concentrations in the locus coeruleus (LC), A1/C1 and A2/C2 catecholaminergic cell groups, hippocampus, amygdala, nucleus basalis magnocellularis, and frontal cortex of unstressed, singly stressed or repeatedly stressed mice. Moreover, gene expression and protein levels of tyrosine hydroxylase (TH) and CRH receptor mRNA were determined in the LC. Plasma corticosterone levels were also measured. Exposure to a single stress increases tau phosphorylation throughout the brain in WT mice when compared to singly stressed CRH KO animals. In contrast, repeatedly stressed CRH KO mice showed exaggerated tau phosphorylation relative to WT controls. We also observed differences in extent of tau phosphorylation between investigated structures, e.g. the LC and hippocampus. Moreover, CRH deficiency leads to different responses to stress in gene expression of TH, NE concentrations, CRH receptor mRNA, and plasma corticosterone levels. Our data indicate that CRH effects on tau phosphorylation are dependent on whether stress is single or repeated, and differs between brain regions. Our findings indicate that CRH attenuates mechanisms responsible for development of stress-induced tau neuropathology, particularly in conditions of chronic stress. However, the involvement of central catecholaminergic neurons in these mechanisms remains unclear and is in need of further investigation.

  11. Humanized HLA-DR4.RagKO.IL2RγcKO.NOD (DRAG) mice sustain the complex vertebrate life cycle of Plasmodium falciparum malaria.

    PubMed

    Wijayalath, Wathsala; Majji, Sai; Villasante, Eileen F; Brumeanu, Teodor D; Richie, Thomas L; Casares, Sofia

    2014-09-30

    Malaria is a deadly infectious disease affecting millions of people in tropical and sub-tropical countries. Among the five species of Plasmodium parasites that infect humans, Plasmodium falciparum accounts for the highest morbidity and mortality associated with malaria. Since humans are the only natural hosts for P. falciparum, the lack of convenient animal models has hindered the understanding of disease pathogenesis and prompted the need of testing anti-malarial drugs and vaccines directly in human trials. Humanized mice hosting human cells represent new pre-clinical models for infectious diseases that affect only humans. In this study, the ability of human-immune-system humanized HLA-DR4.RagKO.IL2RγcKO.NOD (DRAG) mice to sustain infection with P. falciparum was explored. Four week-old DRAG mice were infused with HLA-matched human haematopoietic stem cells (HSC) and examined for reconstitution of human liver cells and erythrocytes. Upon challenge with infectious P. falciparum sporozoites (NF54 strain) humanized DRAG mice were examined for liver stage infection, blood stage infection, and transmission to Anopheles stephensi mosquitoes. Humanized DRAG mice reconstituted human hepatocytes, Kupffer cells, liver endothelial cells, and erythrocytes. Upon intravenous challenge with P. falciparum sporozoites, DRAG mice sustained liver to blood stage infection (average 3-5 parasites/microlitre blood) and allowed transmission to An. stephensi mosquitoes. Infected DRAG mice elicited antibody and cellular responses to the blood stage parasites and self-cured the infection by day 45 post-challenge. DRAG mice represent the first human-immune-system humanized mouse model that sustains the complex vertebrate life cycle of P. falciparum without the need of exogenous injection of human hepatocytes/erythrocytes or P. falciparum parasite adaptation. The ability of DRAG mice to elicit specific human immune responses to P. falciparum parasites may help deciphering immune correlates

  12. Attraction thresholds and sex discrimination of urinary odorants in male and female aromatase knockout (ArKO) mice.

    PubMed

    Pierman, Sylvie; Douhard, Quentin; Balthazart, Jacques; Baum, Michael J; Bakker, Julie

    2006-01-01

    We previously found that both male and female aromatase knockout (ArKO) mice, which cannot synthesize estrogens due to a targeted mutation of the aromatase gene, showed less investigation of volatile body odors from anesthetized conspecifics of both sexes in Y-maze tests. We now ask whether ArKO mice are in fact capable of discriminating between and/or responding to volatile odors. Using habituation/dishabituation tests, we found that gonadectomized ArKO and wild-type (WT) mice of both sexes, which were tested without any sex hormone replacement, reliably distinguished between undiluted volatile urinary odors of either adult males or estrous females versus deionized water as well as between these two urinary odors themselves. However, ArKO mice of both sexes were less motivated than WT controls to investigate same-sex odors when they were presented last in the sequence of stimuli. In a second experiment, we compared the ability of ArKO and WT mice to respond to decreasing concentrations of either male or female urinary odors. We found a clear-cut sex difference in urinary odor attraction thresholds among WT mice: WT males failed to respond to urine dilutions higher than 1:20 by volume, whereas WT females continued to respond to urine dilutions up to 1:80. Male ArKO mice resembled WT females in their ability to respond to lower concentrations of urinary odors, raising the possibility that the observed sex difference among WT mice in urine attraction thresholds results from the perinatal actions of estrogen in the male nervous system. Female ArKO mice failed to show significant dishabituation responses to two (1:20 and 1:80) dilutions of female urine, perhaps, again, because of a reduced motivation to investigate less salient, same-sex urinary odors. Previously observed deficits in the preference of ArKO male and female mice to approach volatile body odors from conspecifics of either sex cannot be attributed to an inability of ArKO subjects to discriminate these

  13. CaV3.2 KO mice have altered retinal waves but normal direction selectivity.

    PubMed

    Hamby, Aaron M; Rosa, Juliana M; Hsu, Ching-Hsiu; Feller, Marla B

    2015-01-01

    Early in development, before the onset of vision, the retina establishes direction-selective responses. During this time period, the retina spontaneously generates bursts of action potentials that propagate across its extent. The precise spatial and temporal properties of these "retinal waves" have been implicated in the formation of retinal projections to the brain. However, their role in the development of direction selective circuits within the retina has not yet been determined. We addressed this issue by combining multielectrode array and cell-attached recordings to examine mice that lack the CaV3.2 subunit of T-type Ca2+ channels (CaV3.2 KO) because these mice exhibit disrupted waves during the period that direction selective circuits are established. We found that the spontaneous activity of these mice displays wave-associated bursts of action potentials that are altered from that of control mice: the frequency of these bursts is significantly decreased and the firing rate within each burst is reduced. Moreover, the projection patterns of the retina demonstrate decreased eye-specific segregation in the dorsal lateral geniculate nucleus (dLGN). However, after eye-opening, the direction selective responses of CaV3.2 KO direction selective ganglion cells (DSGCs) are indistinguishable from those of wild-type DSGCs. Our data indicate that although the temporal properties of the action potential bursts associated with retinal waves are important for activity-dependent refining of retinal projections to central targets, they are not critical for establishing direction selectivity in the retina.

  14. Ezetimibe potently reduces vascular inflammation and arteriosclerosis in eNOS-deficient ApoE ko mice.

    PubMed

    Kuhlencordt, Peter J; Padmapriya, P; Rützel, S; Schödel, J; Hu, K; Schäfer, A; Huang, P L; Ertl, G; Bauersachs, J

    2009-01-01

    Hypercholesterolemia is associated with decreased vascular nitric oxide bioavailability and deletion of endothelial nitric oxide synthase (eNOS) markedly accelerates atherosclerosis development in apolipoprotein E knockout (apoE ko) mice. The current study tests whether atheroprotection provided by a lipid lowering therapy with Ezetimibe depends on eNOS. ApoE ko and apoE/eNOS double ko (dko) mice received a high fat diet with or without 0.05% Ezetimibe. Ezetimibe significantly reduced plasma cholesterol concentrations and atherogenic lipoproteins in both genotypes to a similar extent. Moreover, the drug reduced vascular inflammation, as it significantly reduced vascular cell adhesion molecule-1 (VCAM-1) expression and vascular CD14 expression, a marker for mononuclear cell infiltration, in both genotypes. Neither NOS protein expression nor vascular reactivity of aortic rings was changed in apoE ko mice following Ezetimibe treatment. Significant lesion reduction was seen in Ezetimibe-treated male and female apoE ko and apoE/eNOS dko animals (pko, compared to male eNOS dko mice, suggesting that lipid lowering does provide additional eNOS-dependent atheroprotection in this experimental group. Lipid lowering with Ezetimibe potently reduces atherosclerosis and vascular inflammation independent of eNOS. Moreover, Ezetimibe did not exert any effects on eNOS protein expression or enzyme activity. However, additional atheroprotection by Ezetimibe was observed in eNOS competent apoE ko mice, suggesting that some of the drug's anti-atherosclerotic effects are mediated by the eNOS pathway.

  15. Ezetimibe potently reduces vascular inflammation and arteriosclerosis in eNOS deficient ApoE ko mice

    PubMed Central

    Kuhlencordt, Peter J.; Padmapriya, P.; Rützel, S.; Schödel, J.; Hu, K.; Schäfer, A.; Huang, P.L.; Ertl, G.; Bauersachs, J.

    2013-01-01

    Objective Hypercholesterolemia is associated with decreased vascular nitric oxide bioavailability and deletion of endothelial nitric oxide synthase (eNOS) markedly accelerates atherosclerosis development in apolipoprotein E knockout (apoE ko) mice. The current study tests whether atheroprotection provided by a lipid lowering therapy with Ezetimibe depends on eNOS. Methods/Results ApoE ko and apoE/eNOS double ko (dko) mice received a high fat diet with or without 0.05% Ezetimibe. Ezetimibe significantly reduced plasma cholesterol concentrations and atherogenic lipoproteins in both genotypes to a similar extent. Moreover, the drug reduced vascular inflammation, as it significantly reduced Vascular Cell Adhesion Molecule-1 (VCAM-1) expression and vascular CD14 expression, a marker for mononuclear cell infiltration, in both genotypes. Neither NOS protein expression nor vascular reactivity of aortic rings were changed in apoE ko mice following Ezetimibe treatment. Significant lesion reduction was seen in Ezetimibe treated male and female apoE ko and apoE/eNOS dko animals (p≤0.05). Interestingly, the drug mediated additional atheroprotection in male apoE ko, compared to male eNOS dko mice, suggesting that lipid lowering does provide additional eNOS dependent atheroprotection in this experimental group. Conclusion Lipid lowering with Ezetimibe potently reduces atherosclerosis and vascular inflammation independent of eNOS. Moreover, Ezetimibe did not exert any effects on eNOS protein expression or enzyme activity. However, additional atheroprotection by Ezetimibe was observed in eNOS competent apoE ko mice, suggesting that some of the drug's antiatherosclerotic effects are mediated by the eNOS pathway. PMID:18479686

  16. Heterozygous Che-1 KO mice show deficiencies in object recognition memory persistence.

    PubMed

    Zalcman, Gisela; Corbi, Nicoletta; Di Certo, Maria Grazia; Mattei, Elisabetta; Federman, Noel; Romano, Arturo

    2016-10-06

    Transcriptional regulation is a key process in the formation of long-term memories. Che-1 is a protein involved in the regulation of gene transcription that has recently been proved to bind the transcription factor NF-κB, which is known to be involved in many memory-related molecular events. This evidence prompted us to investigate the putative role of Che-1 in memory processes. For this study we newly generated a line of Che-1(+/-) heterozygous mice. Che-1 homozygous KO mouse is lethal during development, but Che-1(+/-) heterozygous mouse is normal in its general anatomical and physiological characteristics. We analyzed the behavioral characteristic and memory performance of Che-1(+/-) mice in two NF-κB dependent types of memory. We found that Che-1(+/-) mice show similar locomotor activity and thigmotactic behavior than wild type (WT) mice in an open field. In a similar way, no differences were found in anxiety-like behavior between Che-1(+/-) and WT mice in an elevated plus maze as well as in fear response in a contextual fear conditioning (CFC) and object exploration in a novel object recognition (NOR) task. No differences were found between WT and Che-1(+/-) mice performance in CFC training and when tested at 24h or 7days after training. Similar performance was found between groups in NOR task, both in training and 24h testing performance. However, we found that object recognition memory persistence at 7days was impaired in Che-1(+/-) heterozygous mice. This is the first evidence showing that Che-1 is involved in memory processes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  17. 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

  18. Growth hormone is increased in the lungs and enhances experimental lung metastasis of melanoma in DJ-1 KO mice.

    PubMed

    Chien, Chia-Hung; Lee, Ming-Jen; Liou, Houng-Chi; Liou, Horng-Huei; Fu, Wen-Mei

    2016-11-08

    Growth hormone (GH) mainly serves an endocrine function to regulate somatic growth, but also serves an autocrine function in lung growth and pulmonary function. Several recent studies have demonstrated the role of autocrine GH in tumor progression in some organs. However, it is not clear whether excessive secretion of GH in the lungs is related to pulmonary nodule formation. Firstly, the lung tissues dissected from mice were used for Western blotting and PCR measurement. Secondly, the cultured cells were used for examining effects of GH on B16F10 murine melanoma cells. Thirdly, male C57BL/6 mice were intravenously injected with B16F10 cells and then subcutaneously injected with recombinant GH twice per week for three weeks. Finally, stably transfected pool of B16F10 cells with knockdown of growth hormone receptor (GHR) was used to be injected into mice. We found that expression of GH was elevated in the lungs of DJ-1 knockout (KO) mice. We also examined the effects of GH on the growth of cultured melanoma cells. The results showed that GH increased proliferation, colony formation, and invasive capacity of B16F10 cells. In addition, GH also increased the expression of matrix metalloproteinases (MMPs) in B16F10 cells. Administration of GH in vivo enhanced lung nodule formation in C57/B6 mice. Increased lung nodule formation in DJ-1 KO mice following intravenous injection of melanoma cells was inhibited by GHR knockdown in B16F10 cells. These results indicate that up-regulation of GH in the lungs of DJ-1 KO mice may enhance the malignancy of B16F10 cells and nodule formation in pulmonary metastasis of melanoma.

  19. 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

  20. Enhanced erythropoiesis in Hfe-KO mice indicates a role for Hfe in the modulation of erythroid iron homeostasis

    PubMed Central

    Ramos, Pedro; Guy, Ella; Chen, Nan; Proenca, Catia C.; Gardenghi, Sara; Casu, Carla; Follenzi, Antonia; Van Rooijen, Nico; Grady, Robert W.; de Sousa, Maria

    2011-01-01

    In hereditary hemochromatosis, mutations in HFE lead to iron overload through abnormally low levels of hepcidin. In addition, HFE potentially modulates cellular iron uptake by interacting with transferrin receptor, a crucial protein during erythropoiesis. However, the role of HFE in this process was never explored. We hypothesize that HFE modulates erythropoiesis by affecting dietary iron absorption and erythroid iron intake. To investigate this, we used Hfe-KO mice in conditions of altered dietary iron and erythropoiesis. We show that Hfe-KO mice can overcome phlebotomy-induced anemia more rapidly than wild-type mice (even when iron loaded). Second, we evaluated mice combining the hemochromatosis and β-thalassemia phenotypes. Our results suggest that lack of Hfe is advantageous in conditions of increased erythropoietic activity because of augmented iron mobilization driven by deficient hepcidin response. Lastly, we demonstrate that Hfe is expressed in erythroid cells and impairs iron uptake, whereas its absence exclusively from the hematopoietic compartment is sufficient to accelerate recovery from phlebotomy. In summary, we demonstrate that Hfe influences erythropoiesis by 2 distinct mechanisms: limiting hepcidin expression under conditions of simultaneous iron overload and stress erythropoiesis, and impairing transferrin-bound iron uptake by erythroid cells. Moreover, our results provide novel suggestions to improve the treatment of hemochromatosis. PMID:21059897

  1. Angiotensin-(1-7)-induced Mas receptor activation attenuates atherosclerosis through a nitric oxide-dependent mechanism in apolipoproteinE-KO mice.

    PubMed

    Yang, Guang; Istas, Geoffrey; Höges, Sascha; Yakoub, Mina; Hendgen-Cotta, Ulrike; Rassaf, Tienush; Rodriguez-Mateos, Ana; Hering, Lydia; Grandoch, Maria; Mergia, Evanthia; Rump, Lars Christian; Stegbauer, Johannes

    2018-04-01

    Angiotensin (Ang)-(1-7) ameliorates vascular injury by increasing nitric oxide (NO) bioavailability. Evidence that Ang-(1-7) attenuates the development of atherosclerosis through a NO-dependent mechanism is still missing. Moreover, it has been postulated that Ang-(1-7) may mediate its effects by other mechanisms than Mas receptor activation. To investigate Ang-(1-7)-dependent Mas receptor function, we treated apoE-KO and apoE/Mas-KO mice chronically with Ang-(1-7) (82 μg/kg per hour) or saline for 6 weeks. Flow-mediated dilation (FMD), a measure for NO-dependent vasodilation and the most accepted prognostic marker for the development of atherosclerosis, was measured in vivo. Chronic Ang-(1-7) treatment improved FMD and attenuated the development of atherosclerosis in apolipoproteinE (apoE)-KO but not in apoE/Mas-KO mice. These effects were accompanied by increased aortic nitrite and cGMP levels. To test whether Ang-(1-7) modulates atherosclerosis through a NO-dependent mechanism, apoE-KO mice were treated with the NO synthase inhibitor L-NAME (20 mg/kg/day) in the presence or absence of Ang-(1-7). L-NAME treatment reduced aortic nitrite content and increased blood pressure and exaggerated atherosclerosis compared to untreated apoE-KO mice. In L-NAME-treated apoE-KO mice, chronic Ang-(1-7) treatment did not increase aortic nitrite content and consequently showed no effect on blood pressure and the development of atherosclerosis. The present study proves that Ang-(1-7) mediates its protective vascular effects through Mas receptor activation. Moreover, Ang-(1-7)-mediated NO generation is essential for improving vascular function and prevents atherosclerosis in apoE-KO mice.

  2. Histone acetylation rescues contextual fear conditioning in nNOS KO mice and accelerates extinction of cued fear conditioning in wild type mice.

    PubMed

    Itzhak, Yossef; Anderson, Karen L; Kelley, Jonathan B; Petkov, Martin

    2012-05-01

    Epigenetic regulation of chromatin structure is an essential molecular mechanism that contributes to the formation of synaptic plasticity and long-term memory (LTM). An important regulatory process of chromatin structure is acetylation and deacetylation of histone proteins. Inhibition of histone deacetylase (HDAC) increases acetylation of histone proteins and facilitate learning and memory. Nitric oxide (NO) signaling pathway has a role in synaptic plasticity, LTM and regulation of histone acetylation. We have previously shown that NO signaling pathway is required for contextual fear conditioning. The present study investigated the effects of systemic administration of the HDAC inhibitor sodium butyrate (NaB) on fear conditioning in neuronal nitric oxide synthase (nNOS) knockout (KO) and wild type (WT) mice. The effect of single administration of NaB on total H3 and H4 histone acetylation in hippocampus and amygdala was also investigated. A single administration of NaB prior to fear conditioning (a) rescued contextual fear conditioning of nNOS KO mice and (b) had long-term (weeks) facilitatory effect on the extinction of cued fear memory of WT mice. The facilitatory effect of NaB on extinction of cued fear memory of WT mice was confirmed in a study whereupon NaB was administered during extinction. Results suggest that (a) the rescue of contextual fear conditioning in nNOS KO mice is associated with NaB-induced increase in H3 histone acetylation and (b) the accelerated extinction of cued fear memory in WT mice is associated with NaB-induced increase in H4 histone acetylation. Hence, a single administration of HDAC inhibitor may rescue NO-dependent cognitive deficits and afford a long-term accelerating effect on extinction of fear memory of WT mice. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Influence of breast cancer resistance protein and P-glycoprotein on tissue distribution and excretion of Ko143 assessed with PET imaging in mice.

    PubMed

    Mairinger, Severin; Zoufal, Viktoria; Wanek, Thomas; Traxl, Alexander; Filip, Thomas; Sauberer, Michael; Stanek, Johann; Kuntner, Claudia; Pahnke, Jens; Müller, Markus; Langer, Oliver

    2018-03-30

    Ko143 is a reference inhibitor of the adenosine triphosphate-binding cassette (ABC) transporter breast cancer resistance protein (humans: ABCG2, rodents: Abcg2) for in vitro and in vivo use. Previous in vitro data indicate that Ko143 binds specifically to ABCG2/Abcg2, suggesting a potential utility of Ko143 as a positron emission tomography (PET) tracer to assess the density (abundance) of ABCG2 in different tissues. In this work we radiolabeled Ko143 with carbon-11 ( 11 C) and performed small-animal PET experiments with [ 11 C]Ko143 in wild-type, Abcg2 (-/-) , Abcb1a/b (-/-) and Abcb1a/b (-/-) Abcg2 (-/-) mice to assess the influence of Abcg2 and Abcb1a/b on tissue distribution and excretion of [ 11 C]Ko143. [ 11 C]Ko143 was extensively metabolized in vivo and unidentified radiolabeled metabolites were found in all investigated tissues. We detected no significant differences between wild-type and Abcg2 (-/-) mice in the distribution of [ 11 C]Ko143-derived radioactivity to Abcg2-expressing organs (brain, liver and kidney). [ 11 C]Ko143 and possibly its radiolabeled metabolites were transported by Abcb1a and not by Abcg2 at the mouse blood-brain barrier. [ 11 C]Ko143-derived radioactivity underwent both hepatobiliary and urinary excretion, with Abcg2 playing a possible role in mediating the transport of radiolabeled metabolites of [ 11 C]Ko143 from the kidney into urine. Experiments in which a pharmacologic dose of unlabeled Ko143 (10 mg/kg) was co-administered with [ 11 C]Ko143 revealed pronounced effects of the vehicle used for Ko143 formulation (containing polyethylene glycol 300 and polysorbate 80) on radioactivity distribution to the brain and the liver, as well as on hepatobiliary and urinary excretion of radioactivity. Our results highlight the challenges associated with the development of PET tracers for ABC transporters and emphasize that inhibitory effects of pharmaceutical excipients on membrane transporters need to be considered when performing in

  4. Rescue of fragile X syndrome phenotypes in Fmr1 KO mice by a BKCa channel opener molecule

    PubMed Central

    2014-01-01

    Background Fragile X Syndrome (FXS) is the most common form of inherited intellectual disability and is also associated with autism spectrum disorders. Previous studies implicated BKCa channels in the neuropathogenesis of FXS, but the main question was whether pharmacological BKCa stimulation would be able to rescue FXS neurobehavioral phenotypes. Methods and results We used a selective BKCa channel opener molecule (BMS-204352) to address this issue in Fmr1 KO mice, modeling the FXS pathophysiology. In vitro, acute BMS-204352 treatment (10 μM) restored the abnormal dendritic spine phenotype. In vivo, a single injection of BMS-204352 (2 mg/kg) rescued the hippocampal glutamate homeostasis and the behavioral phenotype. Indeed, disturbances in social recognition and interaction, non-social anxiety, and spatial memory were corrected by BMS-204352 in Fmr1 KO mice. Conclusion These results demonstrate that the BKCa channel is a new therapeutic target for FXS. We show that BMS-204352 rescues a broad spectrum of behavioral impairments (social, emotional and cognitive) in an animal model of FXS. This pharmacological molecule might open new ways for FXS therapy. PMID:25079250

  5. Rescue of fragile X syndrome phenotypes in Fmr1 KO mice by a BKCa channel opener molecule.

    PubMed

    Hébert, Betty; Pietropaolo, Susanna; Même, Sandra; Laudier, Béatrice; Laugeray, Anthony; Doisne, Nicolas; Quartier, Angélique; Lefeuvre, Sandrine; Got, Laurence; Cahard, Dominique; Laumonnier, Frédéric; Crusio, Wim E; Pichon, Jacques; Menuet, Arnaud; Perche, Olivier; Briault, Sylvain

    2014-08-01

    Fragile X Syndrome (FXS) is the most common form of inherited intellectual disability and is also associated with autism spectrum disorders. Previous studies implicated BKCa channels in the neuropathogenesis of FXS, but the main question was whether pharmacological BKCa stimulation would be able to rescue FXS neurobehavioral phenotypes. We used a selective BKCa channel opener molecule (BMS-204352) to address this issue in Fmr1 KO mice, modeling the FXS pathophysiology. In vitro, acute BMS-204352 treatment (10 μM) restored the abnormal dendritic spine phenotype. In vivo, a single injection of BMS-204352 (2 mg/kg) rescued the hippocampal glutamate homeostasis and the behavioral phenotype. Indeed, disturbances in social recognition and interaction, non-social anxiety, and spatial memory were corrected by BMS-204352 in Fmr1 KO mice. These results demonstrate that the BKCa channel is a new therapeutic target for FXS. We show that BMS-204352 rescues a broad spectrum of behavioral impairments (social, emotional and cognitive) in an animal model of FXS. This pharmacological molecule might open new ways for FXS therapy.

  6. Senescent Atrophic Epidermis Retains Lrig1+ Stem Cells and Loses Wnt Signaling, a Phenotype Shared with CD44KO Mice

    PubMed Central

    Barnes, Laurent; Saurat, Jean-Hilaire; Kaya, Gürkan

    2017-01-01

    Lrig1 is known to repress the epidermal growth through its inhibitory activity on EGFR, while CD44 promotes it. We analyzed the expression of these molecules in senescent atrophic human epidermis and in the epidermis of CD44KO mice. In normal human epidermis, Lrig1+ cells form clusters located in the basal layer in which CD44 expression is downregulated and Lef1 expression reflects an active Wnt signaling. In senescent atrophic human epidermis, we found retention of Lrig1high+ cells all along the basal layer, forming no clusters, with decrease of CD44 and lef1 expression. In vitro silencing of CD44 indicated that CD44 may be required for Wnt signaling. However, if looking at the ear epidermis of CD44KO mice, we only found a limited interfollicular epidermal atrophy and unchanged Lrig1high+ cells in the hair follicle. Cell lineage tracing further revealed that interfollicular epidermis did lost its self-renewing capacity but that its homeostasis relied on Lrig1-derived keratinocytes migrating from the hair follicle. Therefore, we conclude that CD44 downregulation is part of the phenotype of senescent atrophic human epidermis, and contributes to reduce Wnt signaling and to alter Lrig1high+ stem cell distribution. PMID:28099467

  7. Senescent Atrophic Epidermis Retains Lrig1+ Stem Cells and Loses Wnt Signaling, a Phenotype Shared with CD44KO Mice.

    PubMed

    Barnes, Laurent; Saurat, Jean-Hilaire; Kaya, Gürkan

    2017-01-01

    Lrig1 is known to repress the epidermal growth through its inhibitory activity on EGFR, while CD44 promotes it. We analyzed the expression of these molecules in senescent atrophic human epidermis and in the epidermis of CD44KO mice. In normal human epidermis, Lrig1+ cells form clusters located in the basal layer in which CD44 expression is downregulated and Lef1 expression reflects an active Wnt signaling. In senescent atrophic human epidermis, we found retention of Lrig1high+ cells all along the basal layer, forming no clusters, with decrease of CD44 and lef1 expression. In vitro silencing of CD44 indicated that CD44 may be required for Wnt signaling. However, if looking at the ear epidermis of CD44KO mice, we only found a limited interfollicular epidermal atrophy and unchanged Lrig1high+ cells in the hair follicle. Cell lineage tracing further revealed that interfollicular epidermis did lost its self-renewing capacity but that its homeostasis relied on Lrig1-derived keratinocytes migrating from the hair follicle. Therefore, we conclude that CD44 downregulation is part of the phenotype of senescent atrophic human epidermis, and contributes to reduce Wnt signaling and to alter Lrig1high+ stem cell distribution.

  8. Reversal of fragile X phenotypes by manipulation of AβPP/Aβ levels in Fmr1KO mice.

    PubMed

    Westmark, Cara J; Westmark, Pamela R; O'Riordan, Kenneth J; Ray, Brian C; Hervey, Crystal M; Salamat, M Shahriar; Abozeid, Sara H; Stein, Kelsey M; Stodola, Levi A; Tranfaglia, Michael; Burger, Corinna; Berry-Kravis, Elizabeth M; Malter, James S

    2011-01-01

    Fragile X syndrome (FXS) is the most common form of inherited intellectual disability and the leading known genetic cause of autism. Fragile X mental retardation protein (FMRP), which is absent or expressed at substantially reduced levels in FXS, binds to and controls the postsynaptic translation of amyloid β-protein precursor (AβPP) mRNA. Cleavage of AβPP can produce β-amyloid (Aβ), a 39-43 amino acid peptide mis-expressed in Alzheimer's disease (AD) and Down syndrome (DS). Aβ is over-expressed in the brain of Fmr1(KO) mice, suggesting a pathogenic role in FXS. To determine if genetic reduction of AβPP/Aβ rescues characteristic FXS phenotypes, we assessed audiogenic seizures (AGS), anxiety, the ratio of mature versus immature dendritic spines and metabotropic glutamate receptor (mGluR)-mediated long-term depression (LTD) in Fmr1(KO) mice after removal of one App allele. All of these phenotypes were partially or completely reverted to normal. Plasma Aβ(1-42) was significantly reduced in full-mutation FXS males compared to age-matched controls while cortical and hippocampal levels were somewhat increased, suggesting that Aβ is sequestered in the brain. Evolving therapies directed at reducing Aβ in AD may be applicable to FXS and Aβ may serve as a plasma-based biomarker to facilitate disease diagnosis or assess therapeutic efficacy.

  9. Residual Chemoresponsiveness to Acids in the Superior Laryngeal Nerve in “Taste-Blind” (P2X2/P2X3 Double-KO) Mice

    PubMed Central

    Ohkuri, Tadahiro; Horio, Nao; Stratford, Jennifer M.; Finger, Thomas E.; Ninomiya, Yuzo

    2012-01-01

    Mice lacking both the P2X2 and the P2X3 purinergic receptors (P2X-dblKO) exhibit loss of responses to all taste qualities in the taste nerves innervating the tongue. Similarly, these mice exhibit a near total loss of taste-related behaviors in brief access tests except for a near-normal avoidance of acidic stimuli. This persistent avoidance of acids despite the loss of gustatory neural responses to sour was postulated to be due to continued responsiveness of the superior laryngeal (SL) nerve. However, chemoresponses of the larynx are attributable both to taste buds and to free nerve endings. In order to test whether the SL nerve of P2X-dblKO mice remains responsive to acids but not to other tastants, we recorded responses from the SL nerve in wild-type (WT) and P2X-dblKO mice. WT mice showed substantial SL responses to monosodium glutamate, sucrose, urea, and denatonium—all of which were essentially absent in P2X-dblKO animals. In contrast, the SL nerve of P2X-dblKO mice exhibited near-normal responses to citric acid (50 mM) although responsiveness of both the chorda tympani and the glossopharyngeal nerves to this stimulus were absent or greatly reduced. These results are consistent with the hypothesis that the residual avoidance of acidic solutions by P2X-dblKO mice may be attributable to the direct chemosensitivity of nerve fibers innervating the laryngeal epithelium and not to taste. PMID:22362867

  10. Sustained Toll-Like Receptor 9 Activation Promotes Systemic and Cardiac Inflammation, and Aggravates Diastolic Heart Failure in SERCA2a KO Mice

    PubMed Central

    Dhondup, Yangchen; Sjaastad, Ivar; Scott, Helge; Sandanger, Øystein; Zhang, Lili; Haugstad, Solveig Bjærum; Aronsen, Jan Magnus; Ranheim, Trine; Holmen, Sigve Dhondup; Alfsnes, Katrine; Ahmed, Muhammad Shakil; Attramadal, Håvard; Gullestad, Lars; Aukrust, Pål; Christensen, Geir; Yndestad, Arne; Vinge, Leif Erik

    2015-01-01

    Aim Cardiac inflammation is important in the pathogenesis of heart failure. However, the consequence of systemic inflammation on concomitant established heart failure, and in particular diastolic heart failure, is less explored. Here we investigated the impact of systemic inflammation, caused by sustained Toll-like receptor 9 activation, on established diastolic heart failure. Methods and Results Diastolic heart failure was established in 8–10 week old cardiomyocyte specific, inducible SERCA2a knock out (i.e., SERCA2a KO) C57Bl/6J mice. Four weeks after conditional KO, mice were randomized to receive Toll-like receptor 9 agonist (CpG B; 2μg/g body weight) or PBS every third day. After additional four weeks, echocardiography, phase contrast magnetic resonance imaging, histology, flow cytometry, and cardiac RNA analyses were performed. A subgroup was followed, registering morbidity and death. Non-heart failure control groups treated with CpG B or PBS served as controls. Our main findings were: (i) Toll-like receptor 9 activation (CpG B) reduced life expectancy in SERCA2a KO mice compared to PBS treated SERCA2a KO mice. (ii) Diastolic function was lower in SERCA2a KO mice with Toll-like receptor 9 activation. (iii) Toll-like receptor 9 stimulated SERCA2a KO mice also had increased cardiac and systemic inflammation. Conclusion Sustained activation of Toll-like receptor 9 causes cardiac and systemic inflammation, and deterioration of SERCA2a depletion-mediated diastolic heart failure. PMID:26461521

  11. Osteoblastic Lrp4 promotes osteoclastogenesis by regulating ATP release and adenosine-A2AR signaling

    PubMed Central

    Xiong, Lei; Jung, Ji-Ung; Guo, Hao-Han; Pan, Jin-Xiu; Sun, Xiang-Dong

    2017-01-01

    Bone homeostasis depends on the functional balance of osteoblasts (OBs) and osteoclasts (OCs). Lrp4 is a transmembrane protein that is mutated in patients with high bone mass. Loss of Lrp4 in OB-lineage cells increases bone mass by elevating bone formation by OBs and reducing bone resorption by OCs. However, it is unclear how Lrp4 deficiency in OBs impairs osteoclastogenesis. Here, we provide evidence that loss of Lrp4 in the OB lineage stabilizes the prorenin receptor (PRR) and increases PRR/V-ATPase–driven ATP release, thereby enhancing the production of the ATP derivative adenosine. Both pharmacological and genetic inhibition of adenosine-2A receptor (A2AR) in culture and Lrp4 mutant mice diminishes the osteoclastogenic deficit and reduces trabecular bone mass. Furthermore, elevated adenosine-A2AR signaling reduces receptor activator of nuclear factor κB (RANK)–mediated osteoclastogenesis. Collectively, these results identify a mechanism by which osteoblastic Lrp4 controls osteoclastogenesis, reveal a cross talk between A2AR and RANK signaling in osteoclastogenesis, and uncover an unrecognized pathophysiological mechanism of high-bone-mass disorders. PMID:28193701

  12. Calcium sensitivity and myofilament lattice structure in titin N2B KO mice.

    PubMed

    Lee, Eun-Jeong; Nedrud, Joshua; Schemmel, Peter; Gotthardt, Michael; Irving, Thomas C; Granzier, Henk L

    2013-07-01

    The cellular basis of the Frank-Starling "Law of the Heart" is the length-dependence of activation, but the mechanisms by which the sarcomere detects length changes and converts this information to altered calcium sensitivity has remained elusive. Here the effect of titin-based passive tension on the length-dependence of activation (LDA) was studied by measuring the tension-pCa relation in skinned mouse LV muscle at two sarcomere lengths (SLs). N2B KO myocardium, where the N2B spring element in titin is deleted and passive tension is elevated, was compared to WT myocardium. Myofilament lattice structure was studied with low-angle X-ray diffraction; the myofilament lattice spacing (d1,0) was measured as well as the ratio of the intensities of the 1,1 and 1,0 diffraction peaks (I1,1/I1,0) as an estimate of the degree of association of myosin heads with the thin filaments. Experiments were carried out in skinned muscle in which the lattice spacing was reduced with Dextran-T500. Experiments with and without lattice compression were also carried out following PKA phosphorylation of the skinned muscle. Under all conditions that were tested, LDA was significantly larger in N2B KO myocardium compared to WT myocardium, with the largest differences following PKA phosphorylation. A positive correlation between passive tension and LDA was found that persisted when the myofilament lattice was compressed with Dextran and that was enhanced following PKA phosphorylation. Low-angle X-ray diffraction revealed a shift in mass from thin filaments to thick filaments as sarcomere length was increased. Furthermore, a positive correlation was obtained between myofilament lattice spacing and passive tension and the change in I1,1/I1,0 and passive tension and these provide possible explanations for how titin-based passive tension might regulate calcium sensitivity. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. MicroRNA and Transcriptomic Profiling Showed miRNA-Dependent Impairment of Systemic Regulation and Synthesis of Biomolecules in Rag2 KO Mice.

    PubMed

    Reza, Abu Musa Md Talimur; Choi, Yun-Jung; Kim, Jin-Hoi

    2018-02-27

    The Rag2 knockout (KO) mouse is a well-established immune-compromised animal model for biomedical research. A comparative study identified the deregulated expression of microRNAs (miRNAs) and messenger RNAs (mRNAs) in Rag2 KO mice. However, the interaction between deregulated genes and miRNAs in the alteration of systemic (cardiac, renal, hepatic, nervous, and hematopoietic) regulations and the synthesis of biomolecules (such as l-tryptophan, serotonin, melatonin, dopamine, alcohol, noradrenaline, putrescine, and acetate) are unclear. In this study, we analyzed both miRNA and mRNA expression microarray data from Rag2 KO and wild type mice to investigate the possible role of miRNAs in systemic regulation and biomolecule synthesis. A notable finding obtained from this analysis is that the upregulation of several genes which are target molecules of the downregulated miRNAs in Rag2 KO mice, can potentially trigger the degradation of l-tryptophan, thereby leading to the systemic impairment and alteration of biomolecules synthesis as well as changes in behavioral patterns (such as stress and fear responses, and social recognition memory) in Rag2 gene-depleted mice. These findings were either not observed or not explicitly described in other published Rag2 KO transcriptome analyses. In conclusion, we have provided an indication of miRNA-dependent regulations of clinical and pathological conditions in cardiac, renal, hepatic, nervous, and hematopoietic systems in Rag2 KO mice. These results may significantly contribute to the prediction of clinical disease caused by Rag2 deficiency.

  14. Specific suppression of insulin sensitivity in growth hormone receptor gene-disrupted (GHR-KO) mice attenuates phenotypic features of slow aging

    PubMed Central

    Arum, Oge; Boparai, Ravneet K; Saleh, Jamal K; Wang, Feiya; Dirks, Angela L; Turner, Jeremy G; Kopchick, John J; Liu, Jun-Li; Khardori, Romesh K; Bartke, Andrzej

    2014-01-01

    In addition to their extended lifespans, slow-aging growth hormone receptor/binding protein gene-disrupted (knockout) (GHR-KO) mice are hypoinsulinemic and highly sensitive to the action of insulin. It has been proposed that this insulin sensitivity is important for their longevity and increased healthspan. We tested whether this insulin sensitivity of the GHR-KO mouse is necessary for its retarded aging by abrogating that sensitivity with a transgenic alteration that improves development and secretory function of pancreatic β-cells by expressing Igf-1 under the rat insulin promoter 1 (RIP::IGF-1). The RIP::IGF-1 transgene increased circulating insulin content in GHR-KO mice, and thusly fully normalized their insulin sensitivity, without affecting the proliferation of any non-β-cell cell types. Multiple (nonsurvivorship) longevity-associated physiological and endocrinological characteristics of these mice (namely beneficial blood glucose regulatory control, altered metabolism, and preservation of memory capabilities) were partially or completely normalized, thus supporting the causal role of insulin sensitivity for the decelerated senescence of GHR-KO mice. We conclude that a delayed onset and/or decreased pace of aging can be hormonally regulated. PMID:25244225

  15. Structural, mechanical and myogenic properties of small mesenteric arteries from ApoE KO mice: characterization and effects of virgin olive oil diets.

    PubMed

    Ogalla, Elena; Claro, Carmen; Alvarez de Sotomayor, María; Herrera, Maria Dolores; Rodriguez-Rodriguez, Rosalia

    2015-01-01

    We analyzed the structural, mechanical, myogenic and functional properties of resistance arteries of ApoE KO compared to wild type (WT) mice. We also determined the influence of saturated fat in comparison to virgin olive oil-enriched diets in vascular wall abnormalities. Male ApoE KO (ApoE) and WT mice (8-weeks-old) were assigned to the groups: standard chow diet (SD), high fat diet (HFD), virgin olive oil (VOO) and high polyphenol-VOO-enriched diet (Oleaster(®)) (OT) (15% w/w). After 20 weeks, structural, mechanical and myogenic properties of isolated small mesenteric arteries (SMA) were analyzed by pressure myography. For functional studies, vasodilatation to acetylcholine was assessed. Arterial superoxide anion production was measured by ethidium fluorescence. Hypertrophic remodeling and distensibility in ApoE KO SMA was lower compared to WT mice, suggesting an alteration in the autoregulation mechanisms aimed to compensate disease progression. However, ApoE deficiency resulted in a lower impairment in myogenic tone in response to intraluminal pressure, in addition to an improved endothelium-dependent hyperpolarizing vasodilatation. Also, we evidenced the beneficial effects of VOO in contrast to a saturated fat-enriched diet on SMA wall disorders. Only the endothelial function improvement induced by olive oil was dependent on polyphenols content. Resistance arteries structure, mechanic, myogenic and functional responses from ApoE KO mice significantly differ from WT mice, evidencing the influence of the type of diet on these disorders. These results are particularly useful to determine the contribution of resistance arteries during the atherosclerotic process and to provide novel insights into the Mediterranean dietary pattern to reduce the burden of atherosclerotic disease. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. MC5r and A2Ar Deficiencies During Experimental Autoimmune Uveitis Identifies Distinct T cell Polarization Programs and a Biphasic Regulatory Response

    PubMed Central

    Lee, Darren J.; Preble, Janine; Lee, Stacey; Foster, C. Stephen; Taylor, Andrew W.

    2016-01-01

    Autoantigen-specific regulatory immunity emerges in the spleen of mice recovering from experimental autoimmune uveitis (EAU), a murine model for human autoimmune uveoretinitis. This regulatory immunity provides induced tolerance to ocular autoantigen, and requires melanocortin 5 receptor (MC5r) expression on antigen presenting cells with adenosine 2 A receptor (A2Ar) expression on T cells. During EAU it is not well understood what roles MC5r and A2Ar have on promoting regulatory immunity. Cytokine profile analysis during EAU revealed MC5r and A2Ar each mediate distinct T cell responses, and are responsible for a functional regulatory immune response in the spleen. A2Ar stimulation at EAU onset did not augment this regulatory response, nor bypass the MC5r requirement to induce regulatory immunity. The importance of this pathway in human autoimmune uveitis was assayed. PBMC from uveitis patients were assayed for MC5r expression on monocytes and A2Ar on T cells, and comparison between uveitis patients and healthy controls had no significant difference. The importance for MC5r and A2Ar expression in EAU to promote the induction of protective regulatory immunity, and the expression of MC5r and A2Ar on human immune cells, suggests that it may be possible to utilize the melanocortin-adenosinergic pathways to induce protective immunity in uveitic patients. PMID:27886238

  17. Understanding the Role of Adenosine A2AR Heteroreceptor Complexes in Neurodegeneration and Neuroinflammation.

    PubMed

    Borroto-Escuela, Dasiel O; Hinz, Sonja; Navarro, Gemma; Franco, Rafael; Müller, Christa E; Fuxe, Kjell

    2018-01-01

    Adenosine is a nucleoside mainly formed by degradation of ATP, located intracellularly or extracellularly, and acts as a neuromodulator. It operates as a volume transmission signal through diffusion and flow in the extracellular space to modulate the activity of both glial cells and neurons. The effects of adenosine are mediated via four adenosine receptor subtypes: A1R, A2AR, A2BR, A3R. The A2AR has a wide-spread distribution but it is especially enriched in the ventral and dorsal striatum where it is mainly located in the striato-pallidal GABA neurons at a synaptic and extrasynaptic location. A number of A2AR heteroreceptor complexes exist in the striatum. The existence of A2AR-D2R heteroreceptor complexes with antagonistic A2AR-D2R interactions in the striato-pallidal GABA neurons is well-known with A2AR activation inhibiting Gi/o mediated signaling of D2Rs. A2AR-mGluR5 heteroreceptor complexes were also found in with synergistic receptor-receptor interactions enhancing the inhibition of the D2R protomer signaling. They are located mainly in extrasynaptic regions of the striato-pallidal GABA neurons. Results recently demonstrated the existence of brain A2AR-A2BR heteroreceptor complexes, in which A2BR protomer constitutively inhibited the function of the A2AR protomer. These adenosine A2AR heteroreceptor complexes may modulate alpha-synuclein aggregation and toxicity through postulated bidirectional direct interactions leading to marked increases in A2AR signaling both in nerve cells and microglia. It is of high interest that formation of A2AR-A2ABR heteroreceptor complexes provides a brake on A2AR recognition and signaling opening up a novel strategy for treatment of A2AR mediated neurodegeneration.

  18. Gene expression analysis in Fmr1KO mice identifies an immunological signature in brain tissue and mGluR5-related signaling in primary neuronal cultures.

    PubMed

    Prilutsky, Daria; Kho, Alvin T; Palmer, Nathan P; Bhakar, Asha L; Smedemark-Margulies, Niklas; Kong, Sek Won; Margulies, David M; Bear, Mark F; Kohane, Isaac S

    2015-01-01

    responsible for the immunological phenotype in the intact brain. Our results suggest that cultured cells may recapitulate an early phase of the disease, which is also less obscured with a consequent "immunological" phenotype and in vivo compensatory mechanisms observed in the embryonic brain. Together, these results suggest that the transcriptome of cultured primary neuronal cells, in comparison to whole brain tissue, more robustly demonstrated the difference between Fmr1KO and WT mice and might reveal a molecular phenotype, which is typically hidden by compensatory mechanisms present in vivo. Moreover, cultures might be useful for investigating the perturbed pathways in early human brain development and genes previously implicated in autism.

  19. SNP in human ARHGEF3 promoter is associated with DNase hypersensitivity, transcript level and platelet function, and Arhgef3 KO mice have increased mean platelet volume

    PubMed Central

    Zou, Siying; Teixeira, Alexandra M.; Kostadima, Myrto; Astle, William J.; Radhakrishnan, Aparna; Simon, Lukas Mikolaj; Truman, Lucy; Fang, Jennifer S.; Hwa, John; Zhang, Ping-xia; van der Harst, Pim; Bray, Paul F.; Ouwehand, Willem H.; Frontini, Mattia

    2017-01-01

    Genome-wide association studies have identified a genetic variant at 3p14.3 (SNP rs1354034) that strongly associates with platelet number and mean platelet volume in humans. While originally proposed to be intronic, analysis of mRNA expression in primary human hematopoietic subpopulations reveals that this SNP is located directly upstream of the predominantly expressed ARHGEF3 isoform in megakaryocytes (MK). We found that ARHGEF3, which encodes a Rho guanine exchange factor, is dramatically upregulated during both human and murine MK maturation. We show that the SNP (rs1354034) is located in a DNase I hypersensitive region in human MKs and is an expression quantitative locus (eQTL) associated with ARHGEF3 expression level in human platelets, suggesting that it may be the causal SNP that accounts for the variations observed in human platelet traits and ARHGEF3 expression. In vitro human platelet activation assays revealed that rs1354034 is highly correlated with human platelet activation by ADP. In order to test whether ARHGEF3 plays a role in MK development and/or platelet function, we developed an Arhgef3 KO/LacZ reporter mouse model. Reflecting changes in gene expression, LacZ expression increases during MK maturation in these mice. Although Arhgef3 KO mice have significantly larger platelets, loss of Arhgef3 does not affect baseline MK or platelets nor does it affect platelet function or platelet recovery in response to antibody-mediated platelet depletion compared to littermate controls. In summary, our data suggest that modulation of ARHGEF3 gene expression in humans with a promoter-localized SNP plays a role in human MKs and human platelet function—a finding resulting from the biological follow-up of human genetic studies. Arhgef3 KO mice partially recapitulate the human phenotype. PMID:28542600

  20. mTOR regulates the expression of DNA damage response enzymes in long-lived Snell dwarf, GHRKO, and PAPPA-KO mice.

    PubMed

    Dominick, Graham; Bowman, Jacqueline; Li, Xinna; Miller, Richard A; Garcia, Gonzalo G

    2017-02-01

    Studies of the mTOR pathway have prompted speculation that diminished mTOR complex-1 (mTORC1) function may be involved in controlling the aging process. Our previous studies have shown diminished mTORC1 activity in tissues of three long-lived mutant mice: Snell dwarf mice, growth hormone receptor gene disrupted mice (GHRKO), and in this article, mice deficient in the pregnancy-associated protein-A (PAPPA-KO). The ways in which lower mTOR signals slow aging and age-related diseases are, however, not well characterized. Here, we show that Snell, GHKRO, and PAPPA-KO mice express high levels of two proteins involved in DNA repair, O-6-methylguanine-DNA methyltransferase (MGMT) and N-myc downstream-regulated gene 1 (NDRG1). Furthermore, we report that lowering mTOR enhances MGMT and NDRG1 protein expression via post-transcriptional mechanisms. We show that the CCR4-NOT complex, a post-transcriptional regulator of gene expression, is downstream of the mTORC1 pathway and may be responsible for the upregulation of MGMT and NDRG1 in all three varieties of long-lived mice. Our data thus suggest a novel link between DNA repair and mTOR signaling via post-transcriptional regulation involving specific alteration in the CCR4-NOT complex, whose modulation could control multiple aspects of the aging process. © 2016 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  1. Murine cytomegalovirus (MCMV) infection upregulates P38 MAP kinase in aortas of Apo E KO mice: a molecular mechanism for MCMV-induced acceleration of atherosclerosis.

    PubMed

    Tang-Feldman, Yajarayma J; Lochhead, Stephanie R; Lochhead, G Raymond; Yu, Cindy; George, Michael; Villablanca, Amparo C; Pomeroy, Claire

    2013-02-01

    Multiple studies suggest an association between cytomegalovirus (CMV) infection and atherogenesis; however, the molecular mechanisms by which viral infection might exacerbate atherosclerosis are not well understood. Aortas of MCMV-infected and uninfected Apo E knockout (KO) mice were analyzed for atherosclerotic lesion development and differential gene expression. Lesions in the infected mice were larger and showed more advanced disease compared to the uninfected mice. Sixty percent of the genes in the MAPK pathway were upregulated in the infected mice. p38 and ERK 1/2 MAPK genes were 5.6- and 2.0-fold higher, respectively, in aortas of infected vs. uninfected mice. Levels of VCAM-1, ICAM-1, and MCP-1 were ~2.0-2.6-fold higher in aortas of infected vs. uninfected mice. Inhibition of p38 with SB203580 resulted in lower levels of pro-atherogenic molecules and MCMV viral load in aortas of infected mice. MCMV-induced upregulation of p38 may drive the virus-induced acceleration of atherogenesis observed in our model.

  2. Perilla Oil Reduces Fatty Streak Formation at Aortic Sinus via Attenuation of Plasma Lipids and Regulation of Nitric Oxide Synthase in ApoE KO Mice.

    PubMed

    Hong, Sun Hee; Kim, Mijeong; Noh, Jeong Sook; Song, Yeong Ok

    2016-10-01

    Consumption of n-3 polyunsaturated fatty acids (PUFA) is associated with a reduced incidence of atherosclerosis. Perilla oil (PO) is a vegetable oil rich in α-linolenic acid (ALA), an n-3 PUFA. In this study, antiatherogenic effects and related mechanisms of PO were investigated in atherosclerotic mice. Apolipoprotein E knockout (ApoE KO) mice (male, n = 27) were fed high-cholesterol and high-fat diets containing 10 % w/w lard (LD), PO, or sunflower oil (SO) for 10 weeks. Plasma triglyceride, total cholesterol, and low-density lipoprotein cholesterol concentrations reduced in the PO and SO groups compared to the concentrations in the LD group (P < 0.05). The PO group showed reduced fatty streak lesion size at the aortic sinus (P < 0.05) compared to the sizes in the LD and SO groups. A morphometric analysis showed enhancement of endothelial nitric oxide synthase expression and reduction of inducible nitric oxide synthase expression in the PO group compared to that in the LD group (P < 0.05). Furthermore, aortic protein expression of intercellular cell adhesion molecule 1 and vascular cell adhesion molecule 1 was diminished in the PO group compared to that in the LD and SO groups (P < 0.05). These findings suggested that PO inhibited the development of aortic atherosclerosis by improving the plasma lipid profile, regulating nitric oxide synthase, and suppressing the vascular inflammatory response in the aorta of ApoE KO mice.

  3. Comparison of dentoalveolar morphology in WT and P2X7R KO mice for the development of biomechanical orthodontic models.

    PubMed

    Viecilli, Rodrigo; Katona, Thomas; Chen, Jie; Roberts, Eugene; Hartsfield, James

    2009-02-01

    It has been suggested that the absence of the P2X7 receptor affects long bone morphology, and that one of the cytokines dependent on its activation may also affect tooth morphology. P2X7R KO (knockout) were compared with C57B/6 WT mice (background strain) to identify differences in a maxillary molar and surrounding bone. Nineteen WT and 12 KO mouse maxillae were scanned and 3D-reconstructed using microCT. Tooth dimensions were measured and 3D bone morphometry was conducted. A finite element model was constructed based on the results. No statistically significant differences were found in dentoalveolar characteristics between the two mouse types. A single finite element model of the tooth can be used to mechanically represent both strains. P2X7R does not have a major effect on alveolar bone or tooth morphology. The P2X7R effects are site-specific. (c) 2008 Wiley-Liss, Inc.

  4. Ocular and systemic safety of a recombinant AAV8 vector for X-linked retinoschisis gene therapy: GLP studies in rabbits and Rs1-KO mice

    PubMed Central

    Marangoni, Dario; Bush, Ronald A; Zeng, Yong; Wei, Lisa L; Ziccardi, Lucia; Vijayasarathy, Camasamudram; Bartoe, Joshua T; Palyada, Kiran; Santos, Maria; Hiriyanna, Suja; Wu, Zhijian; Colosi, Peter; Sieving, Paul A

    2016-01-01

    X-linked retinoschisis (XLRS) is a retinal disease caused by mutations in the gene encoding the protein retinoschisin (RS1) and is one of the most common causes of macular degeneration in young men. Our therapeutic approach for XLRS is based on the administration of AAV8-scRS/IRBPhRS, an adeno-associated viral vector coding the human RS1 protein, via the intravitreal (IVT) route. Two Good Laboratory Practice studies, a 9-month study in New Zealand White rabbits (n = 124) injected with AAV8-scRS/IRBPhRS at doses of 2E9, 2E10, 2E11, and 1.5E12 vector genomes/eye (vg/eye), and a 6-month study in Rs1-KO mice (n = 162) dosed with 2E9 and 2E10 vg/eye of the same vector were conducted to assess ocular and systemic safety. A self-resolving, dose-dependent vitreal inflammation was the main ocular finding, and except for a single rabbit dosed with 1.5E12 vg/eye, which showed a retinal detachment, no other ocular adverse event was reported. Systemic toxicity was not identified in either species. Biodistribution analysis in Rs1-KO mice detected spread of vector genome in extraocular tissues, but no evidence of organ or tissues damage was found. These studies indicate that IVT administration of AAV8-scRS/IRBPhRS is safe and well tolerated and support its advancement into a phase 1/2a clinical trial for XLRS. PMID:27626041

  5. Ocular and systemic safety of a recombinant AAV8 vector for X-linked retinoschisis gene therapy: GLP studies in rabbits and Rs1-KO mice.

    PubMed

    Marangoni, Dario; Bush, Ronald A; Zeng, Yong; Wei, Lisa L; Ziccardi, Lucia; Vijayasarathy, Camasamudram; Bartoe, Joshua T; Palyada, Kiran; Santos, Maria; Hiriyanna, Suja; Wu, Zhijian; Colosi, Peter; Sieving, Paul A

    2016-01-01

    X-linked retinoschisis (XLRS) is a retinal disease caused by mutations in the gene encoding the protein retinoschisin (RS1) and is one of the most common causes of macular degeneration in young men. Our therapeutic approach for XLRS is based on the administration of AAV8-scRS/IRBPhRS, an adeno-associated viral vector coding the human RS1 protein, via the intravitreal (IVT) route. Two Good Laboratory Practice studies, a 9-month study in New Zealand White rabbits (n = 124) injected with AAV8-scRS/IRBPhRS at doses of 2E9, 2E10, 2E11, and 1.5E12 vector genomes/eye (vg/eye), and a 6-month study in Rs1-KO mice (n = 162) dosed with 2E9 and 2E10 vg/eye of the same vector were conducted to assess ocular and systemic safety. A self-resolving, dose-dependent vitreal inflammation was the main ocular finding, and except for a single rabbit dosed with 1.5E12 vg/eye, which showed a retinal detachment, no other ocular adverse event was reported. Systemic toxicity was not identified in either species. Biodistribution analysis in Rs1-KO mice detected spread of vector genome in extraocular tissues, but no evidence of organ or tissues damage was found. These studies indicate that IVT administration of AAV8-scRS/IRBPhRS is safe and well tolerated and support its advancement into a phase 1/2a clinical trial for XLRS.

  6. Sequence diversity of dengue virus type 2 in brain and thymus of infected interferon receptor ko mice: implications for dengue virulence.

    PubMed

    Dhole, Priya; Nakayama, Emi E; Saito, Akatsuki; Limkittikul, Kriengsak; Phanthanawiboon, Supranee; Shioda, Tatsuo; Kurosu, Takeshi

    2016-11-30

    We previously reported that a clinical isolate of dengue virus (DENV) is capable of causing acute-phase systemic infection in mice harboring knockouts of the genes encoding type-I and -II interferon IFN receptors (IFN-α/β/γR KO mice); in contrast, other virulent DENV isolates exhibited slow disease progression in this mice, yielding lethal infection around 20 days post-infection (p.i.). In the present study, we sought to clarify the dynamics of slow disease progression by examining disease progression of a type-2 DENV clinical isolate (DV2P04/08) in mice. The tissue distributions of DV2P04/08 in several organs of infeted mice were examined at different time points. Whole genome viral sequences from organs were determined. At day 6 p.i., high levels of viral RNA (vRNA) were detected in non-neuronal organs (including peritoneal exudate cells (PECs), spleen, kidney, liver, lung, and bone marrow) but not in brain. By day 14 p.i, vRNA levels subsequently decreased in most organs, with the exception of thymus and brain. Sequence analysis of the whole genome of the original P04/08 and those of viruses recovered from mouse brain and thymus demonstrated the presence of both synonymous and non-synonymous mutations. Individual mice showed different virus populations in the brain. The vRNA sequence derived from brain of one mouse was nearly identical to the original DV2P04/08 inoculum, suggesting that there was no need for adaptation of DV2P04/08 for growth in the brain. However, quasispecies (that is, mixed populations, detected as apparent nucleotide mixtures during sequencing) were observed in the thymus of another mouse, and interestingly only mutant population invaded the brain at a late stage of infection. These results suggested that the mouse nearly succeeded in eliminating virus from non-neuronal organs but failed to do so from brain. Although the cause of death by DV2P04/08 infection is likely to be the result of virus invasion to brain, its processes to the

  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. PANDER KO Mice On High-Fat Diet Are Glucose Intolerant Yet Resistant to Fasting Hyperglycemia and Hyperinsulinemia

    PubMed Central

    Robert-Cooperman, Claudia E.; Wilson, Camella G.; Burkhardt, Brant R.

    2011-01-01

    The recent creation of the PANDER knockout (PANKO) and acute mouse models have revealed a biological function in the regulation of glycemic levels via promotion of hepatic glucose production (HGP) and pancreatic β-cell insulin secretion. Therefore, we hypothesized that the absence of PANDER may afford some degree of protection from high-fat diet (HFD) induced fasting hyperglycemia. On HFD, fasting glycemic levels were significantly lower in the PANKO mice. Also, fasting insulin levels and the in-vivo insulin response following glucose injection were inhibited in PANKO mice. The lowered fasting glycemic levels are attributed to decreased HGP due to the absence of PANDER. Overall, our findings further indicate PANDER impacts glycemic levels and may represent a potential but complicated therapeutic target. PMID:21486565

  9. 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

  10. Beta3 adrenoceptors substitute the role of M(2) muscarinic receptor in coping with cold stress in the heart: evidence from M(2)KO mice.

    PubMed

    Benes, Jan; Novakova, Martina; Rotkova, Jana; Farar, Vladimir; Kvetnansky, Richard; Riljak, Vladimir; Myslivecek, Jaromir

    2012-07-01

    We investigated the role of beta3-adrenoceptors (AR) in cold stress (1 or 7 days in cold) in animals lacking main cardioinhibitive receptors-M2 muscarinic receptors (M(2)KO). There was no change in receptor number in the right ventricles. In the left ventricles, there was decrease in binding to all cardiostimulative receptors (beta1-, and beta2-AR) and increase in cardiodepressive receptors (beta3-AR) in unstressed KO in comparison to WT. The cold stress in WT animals resulted in decrease in binding to beta1- and beta2-AR (to 37%/35% after 1 day in cold and to 27%/28% after 7 days in cold) while beta3-AR were increased (to 216% of control) when 7 days cold was applied. MR were reduced to 46% and 58%, respectively. Gene expression of M2 MR in WT was not changed due to stress, while M3 was changed. The reaction of beta1- and beta2-AR (binding) to cold was similar in KO and WT animals, and beta3-AR in stressed KO animals did not change. Adenylyl cyclase activity was affected by beta3-agonist CL316243 in cold stressed WT animals but CL316243 had almost no effects on adenylyl cyclase activity in stressed KO. Nitric oxide activity (NOS) was not affected by BRL37344 (beta3-agonist) both in WT and KO animals. Similarly, the stress had no effects on NOS activity in WT animals and in KO animals. We conclude that the function of M2 MR is substituted by beta3-AR and that these effects are mediated via adenylyl cyclase rather than NOS.

  11. Expression of HLA Class II Molecules in Humanized NOD.Rag1KO.IL2RgcKO Mice is Critical for Development and Function of Human T and B Cells

    DTIC Science & Technology

    2011-05-17

    Dengue Virus Infection and Virus -Specific HLA-A2 Restricted Immune Responses in Humanized NOD-scid IL2rcnull Mice. PLoS One 4: e7251. 28...reconstituted mice were able to elicit HLA-A2-restricted CD8 T cell responses upon infection with Epstein Barr or dengue virus [27–29]. However, the function...models to study development and function of the human immune system in vivo . J Immunol 176: 2053–2058. 18. Watanabe Y, Takahashi T,

  12. Altered Neocortical Rhythmic Activity States in Fmr1 KO mice are Due to Enhanced mGluR5 Signaling and Involve Changes in Excitatory Circuitry

    PubMed Central

    Hays, Seth A.; Huber, Kimberly M.; Gibson, Jay R.

    2011-01-01

    Despite the pronounced neurological deficits associated with mental retardation and autism, the degree to which neocortical circuit function is altered remains unknown. Here, we study changes in neocortical network function in the form of persistent activity states in the mouse model of Fragile X Syndrome – the Fmr1 knockout (KO). Persistent activity states, or UP states, in the neocortex underlie the slow oscillation which occurs predominantly during slow wave sleep, but may also play a role during awake states. We show that spontaneously occurring UP states in the primary somatosensory cortex are 38-67% longer in Fmr1 KO slices. In vivo, UP states re-occur with a clear rhythmic component consistent with that of the slow oscillation and are similarly longer in the Fmr1 KO. Changes in neocortical excitatory circuitry likely play the major role in this alteration as supported by 3 findings: 1) longer UP states occur in slices of isolated neocortex, 2) pharmacologically isolated excitatory circuits in Fmr1 KO neocortical slices display prolonged bursting states, and 3) selective deletion of Fmr1 in cortical excitatory neurons is sufficient to cause prolonged UP states whereas deletion in inhibitory neurons has no effect. Excess signaling mediated by the group 1 glutamate metabotropic receptor, mGluR5, contributes to the longer UP states. Genetic reduction or pharmacological blockade of mGluR5 rescues the prolonged UP state phenotype. Our results reveal an alteration in network function in a mouse model of intellectual disability and autism which may impact both slow wave sleep and information processing during waking states. PMID:21976507

  13. Synthesis and Evaluation of Phenylxanthine Derivatives as Potential Dual A2AR Antagonists/MAO-B Inhibitors for Parkinson's Disease.

    PubMed

    Wang, Xuebao; Han, Chao; Xu, Yong; Wu, Kaiqi; Chen, Shuangya; Hu, Mangsha; Wang, Luyao; Ye, Yun; Ye, Faqing

    2017-06-17

    The aim of this research was to prove the speculation that phenylxanthine (PX) derivatives possess adenosine A2A receptor (A2AR)-blocking properties and to screening and evaluate these PX derivatives as dual A2AR antagonists/MAO-B inhibitors for Parkinson's disease. To explore this hypothesis, two series of PX derivatives were prepared and their antagonism against A2AR and inhibition against MAO-B were determined in vitro. In order to evaluate further the antiparkinsonian properties, pharmacokinetic and haloperidol-induced catalepsy experiments were carried out in vivo. The PX-D and PX-E analogues acted as potent A2AR antagonists with Ki values ranging from 0.27 to 10 μM, and these analogues displayed relatively mild MAO-B inhibition potencies, with inhibitor dissociation constants (Ki values) ranging from 0.25 to 10 μM. Further, the compounds PX-D-P6 and PX-E-P8 displayed efficacious antiparkinsonian properties in haloperidol-induced catalepsy experiments, verifying that these two compounds were potent A2AR antagonists and MAO-B inhibitors. We conclude that PX-D and PX-E analogues are a promising candidate class of dual-acting compounds for treating Parkinson's disease.

  14. Autonomic Nervous System Involvement in the Giant Axonal Neuropathy (GAN) KO Mouse: Implications for Human Disease

    PubMed Central

    Armao, Diane; Bailey, Rachel M.; Bouldin, Thomas W.; Kim, Yongbaek; Gray, Steven J.

    2016-01-01

    PURPOSE Giant axonal neuropathy (GAN) is an inherited severe sensorimotor neuropathy. The aim of this research was to investigate the neuropathologic features and clinical autonomic nervous system (ANS) phenotype in two GAN knockout (KO) mouse models. Little is known about ANS involvement in GAN in humans, but autonomic signs and symptoms are commonly reported in early childhood. METHODS Routine histology and immunohistochemistry was performed on GAN KO mouse specimens taken at various ages. Enteric dysfunction was assessed by quantifying the frequency, weight, and water content of defecation in GAN KO mice. RESULTS Histological examination of the enteric, parasympathetic and sympathetic ANS of GAN KO mice revealed pronounced and widespread neuronal perikaryal intermediate filament inclusions. These neuronal inclusions served as an easily identifiable, early marker of GAN in young GAN KO mice. Functional studies identified an age-dependent alteration in fecal weight and defecation frequency in GAN KO mice. CONCLUSIONS For the first time in the GAN KO mouse model, we described the early, pronounced and widespread neuropathologic features involving the ANS. In addition, we provided evidence for a clinical autonomic phenotype in GAN KO mice, reflected in abnormal gastrointestinal function. These findings in GAN KO mice suggest that consideration should be given to ANS involvement in human GAN, especially when considering treatments and patient care. PMID:27369358

  15. Autonomic nervous system involvement in the giant axonal neuropathy (GAN) KO mouse: implications for human disease.

    PubMed

    Armao, Diane; Bailey, Rachel M; Bouldin, Thomas W; Kim, Yongbaek; Gray, Steven J

    2016-08-01

    Giant axonal neuropathy (GAN) is an inherited severe sensorimotor neuropathy. The aim of this research was to investigate the neuropathologic features and clinical autonomic nervous system (ANS) phenotype in two GAN knockout (KO) mouse models. Little is known about ANS involvement in GAN in humans, but autonomic signs and symptoms are commonly reported in early childhood. Routine histology and immunohistochemistry was performed on GAN KO mouse specimens taken at various ages. Enteric dysfunction was assessed by quantifying the frequency, weight, and water content of defecation in GAN KO mice. Histological examination of the enteric, parasympathetic and sympathetic ANS of GAN KO mice revealed pronounced and widespread neuronal perikaryal intermediate filament inclusions. These neuronal inclusions served as an easily identifiable, early marker of GAN in young GAN KO mice. Functional studies identified an age-dependent alteration in fecal weight and defecation frequency in GAN KO mice. For the first time in the GAN KO mouse model, we described the early, pronounced and widespread neuropathologic features involving the ANS. In addition, we provided evidence for a clinical autonomic phenotype in GAN KO mice, reflected in abnormal gastrointestinal function. These findings in GAN KO mice suggest that consideration should be given to ANS involvement in human GAN, especially when considering treatments and patient care.

  16. Osteoblastic Lrp4 promotes osteoclastogenesis by regulating ATP release and adenosine-A2AR signaling.

    PubMed

    Xiong, Lei; Jung, Ji-Ung; Guo, Hao-Han; Pan, Jin-Xiu; Sun, Xiang-Dong; Mei, Lin; Xiong, Wen-Cheng

    2017-03-06

    Bone homeostasis depends on the functional balance of osteoblasts (OBs) and osteoclasts (OCs). Lrp4 is a transmembrane protein that is mutated in patients with high bone mass. Loss of Lrp4 in OB-lineage cells increases bone mass by elevating bone formation by OBs and reducing bone resorption by OCs. However, it is unclear how Lrp4 deficiency in OBs impairs osteoclastogenesis. Here, we provide evidence that loss of Lrp4 in the OB lineage stabilizes the prorenin receptor (PRR) and increases PRR/V-ATPase-driven ATP release, thereby enhancing the production of the ATP derivative adenosine. Both pharmacological and genetic inhibition of adenosine- 2A receptor (A 2A R) in culture and Lrp4 mutant mice diminishes the osteoclastogenic deficit and reduces trabecular bone mass. Furthermore, elevated adenosine-A 2A R signaling reduces receptor activator of nuclear factor κB (RANK)-mediated osteoclastogenesis. Collectively, these results identify a mechanism by which osteoblastic Lrp4 controls osteoclastogenesis, reveal a cross talk between A 2A R and RANK signaling in osteoclastogenesis, and uncover an unrecognized pathophysiological mechanism of high-bone-mass disorders. © 2017 Xiong et al.

  17. Tempol prevents cardiac oxidative damage and left ventricular dysfunction in the PPAR-α KO mouse.

    PubMed

    Guellich, Aziz; Damy, Thibaud; Conti, Marc; Claes, Victor; Samuel, Jane-Lise; Pineau, Thierry; Lecarpentier, Yves; Coirault, Catherine

    2013-06-01

    Peroxisome proliferator-activated receptor (PPAR)-α deletion induces a profound decrease in MnSOD activity, leading to oxidative stress and left ventricular (LV) dysfunction. We tested the hypothesis that treatment of PPAR-α knockout (KO) mice with the SOD mimetic tempol prevents the heart from pathological remodelling and preserves LV function. Twenty PPAR-α KO mice and 20 age-matched wild-type mice were randomly treated for 8 wk with vehicle or tempol in the drinking water. LV contractile parameters were determined both in vivo using echocardiography and ex vivo using papillary muscle mechanics. Translational and posttranslational modifications of myosin heavy chain protein as well as the expression and activity of major antioxidant enzymes were measured. Tempol treatment did not affect LV function in wild-type mice; however, in PPAR-α KO mice, tempol prevented the decrease in LV ejection fraction and restored the contractile parameters of papillary muscle, including maximum shortening velocity, maximum extent of shortening, and total tension. Moreover, compared with untreated PPAR-α KO mice, myosin heavy chain tyrosine nitration and anion superoxide production were markedly reduced in PPAR-α KO mice after treatment. Tempol also significantly increased glutathione peroxidase and glutathione reductase activities (~ 50%) in PPAR-α KO mice. In conclusion, these findings demonstrate that treatment with the SOD mimetic tempol can prevent cardiac dysfunction in PPAR-α KO mice by reducing the oxidation of contractile proteins. In addition, we show that the beneficial effects of tempol in PPAR-α KO mice involve activation of the glutathione peroxidase/glutathione reductase system.

  18. Cocaine self-administration specifically increases A2AR-D2R and D2R-sigma1R heteroreceptor complexes in the rat nucleus accumbens shell. Relevance for cocaine use disorder.

    PubMed

    Borroto-Escuela, Dasiel O; Narváez, Manuel; Wydra, Karolina; Pintsuk, Julia; Pinton, Luca; Jimenez-Beristain, Antonio; Di Palma, Michael; Jastrzębska, Joanna; Filip, Malgorzata; Fuxe, Kjell

    2017-04-01

    Adenosine 2A receptor (A2AR) agonists were indicated to reduce cocaine reward and cocaine seeking mainly through activation of antagonistic allosteric A2AR-dopamine D2R (D2R) interactions in A2AR-D2R heteroreceptor complexes. Furthermore, it was shown that modulation of cocaine reward involves antagonistic A2AR-D2R interactions in the ventral but not the dorsal striatum in rats. In the current work the proximity ligation assay (PLA) was used to further study the A2AR-D2R heteroreceptor complexes in the nucleus accumbens shell and core as well as the dorsal striatum under the influence of cocaine self-administration in rats. A significant increase in the A2AR-D2R PLA positive clusters was observed in the nucleus accumbens shell but not in the other regions vs yoked saline controls using the duolink software. Additionally, cocaine self-administration evoked a selective and significant increase in the density of D2R-sigma1R positive clusters in the nucleus accumbens shell vs yoked saline controls, while a significant reduction of the density of the D2R-sigma1R positive clusters was found in the dorsal part of the dorsal striatum. The results suggest that cocaine self-administration can reorganize A2AR and D2R into increased A2AR-D2R heteroreceptor complexes in the nucleus accumbens shell associated with increases in the D2R-sigma1R heteroreceptor complexes in this region. This reorganization can contribute to the demonstrated anti-cocaine actions of A2A receptor agonists and the putative formation of A2AR-D2R-sigma1R heterocomplexes. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Cellular chloride and bicarbonate retention alters intracellular pH regulation in Cftr KO crypt epithelium.

    PubMed

    Walker, Nancy M; Liu, Jinghua; Stein, Sydney R; Stefanski, Casey D; Strubberg, Ashlee M; Clarke, Lane L

    2016-01-15

    Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR), an anion channel providing a major pathway for Cl(-) and HCO3 (-) efflux across the apical membrane of the epithelium. In the intestine, CF manifests as obstructive syndromes, dysbiosis, inflammation, and an increased risk for gastrointestinal cancer. Cftr knockout (KO) mice recapitulate CF intestinal disease, including intestinal hyperproliferation. Previous studies using Cftr KO intestinal organoids (enteroids) indicate that crypt epithelium maintains an alkaline intracellular pH (pHi). We hypothesized that Cftr has a cell-autonomous role in downregulating pHi that is incompletely compensated by acid-base regulation in its absence. Here, 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein microfluorimetry of enteroids showed that Cftr KO crypt epithelium sustains an alkaline pHi and resistance to cell acidification relative to wild-type. Quantitative real-time PCR revealed that Cftr KO enteroids exhibit downregulated transcription of base (HCO3 (-))-loading proteins and upregulation of the basolateral membrane HCO3 (-)-unloader anion exchanger 2 (Ae2). Although Cftr KO crypt epithelium had increased Ae2 expression and Ae2-mediated Cl(-)/HCO3 (-) exchange with maximized gradients, it also had increased intracellular Cl(-) concentration relative to wild-type. Pharmacological reduction of intracellular Cl(-) concentration in Cftr KO crypt epithelium normalized pHi, which was largely Ae2-dependent. We conclude that Cftr KO crypt epithelium maintains an alkaline pHi as a consequence of losing both Cl(-) and HCO3 (-) efflux, which impairs pHi regulation by Ae2. Retention of Cl(-) and an alkaline pHi in crypt epithelium may alter several cellular processes in the proliferative compartment of Cftr KO intestine. Copyright © 2016 the American Physiological Society.

  20. Ko Displacement Theory for Structural Shape Predictions

    NASA Technical Reports Server (NTRS)

    Ko, William L.

    2010-01-01

    The development of the Ko displacement theory for predictions of structure deformed shapes was motivated in 2003 by the Helios flying wing, which had a 247-ft (75-m) wing span with wingtip deflections reaching 40 ft (12 m). The Helios flying wing failed in midair in June 2003, creating the need to develop new technology to predict in-flight deformed shapes of unmanned aircraft wings for visual display before the ground-based pilots. Any types of strain sensors installed on a structure can only sense the surface strains, but are incapable to sense the overall deformed shapes of structures. After the invention of the Ko displacement theory, predictions of structure deformed shapes could be achieved by feeding the measured surface strains into the Ko displacement transfer functions for the calculations of out-of-plane deflections and cross sectional rotations at multiple locations for mapping out overall deformed shapes of the structures. The new Ko displacement theory combined with a strain-sensing system thus created a revolutionary new structure- shape-sensing technology.

  1. Quantitative and qualitative estimation of atherosclerotic plaque burden in vivo at 7T MRI using Gadospin F in comparison to en face preparation evaluated in ApoE KO mice

    PubMed Central

    Jung, Caroline; Christiansen, Sabine; Kaul, Michael Gerhard; Koziolek, Eva; Reimer, Rudolph; Heeren, Jörg; Adam, Gerhard; Heine, Markus; Ittrich, Harald

    2017-01-01

    Background The aim of the study was to quantify atherosclerotic plaque burden by volumetric assessment and T1 relaxivity measurement at 7T MRI using Gadospin F (GDF) in comparison to en face based measurements. Methods and results 9-weeks old ApoE-/- (n = 5 for each group) and wildtype mice (n = 5) were set on high fat diet (HFD). Progression group received MRI at 9, 13, 17 and 21 weeks after HFD initiation. Regression group was reswitched to chow diet (CD) after 13 weeks HFD and monitored with MRI for 12 weeks. MRI was performed before and two hours after iv injection of GDF (100 μmol/kg) at 7T (Clinscan, Bruker) acquiring a 3D inversion recovery gradient echo sequence and T1 Mapping using Saturation Recovery sequences. Subsequently, aortas were prepared for en face analysis using confocal microscopy. Total plaque volume (TPV) and T1 relaxivity were estimated using ImageJ (V. 1.44p, NIH, USA). 2D and 3D en face analysis showed a strong and exponential increase of plaque burden over time, while plaque burden in regression group was less pronounced. Correspondent in vivo MRI measurements revealed a more linear increase of TPV and T1 relaxivity for regression group. A significant correlation was observed between 2D and 3D en face analysis (r = 0.79; p<0.001) as well as between 2D / 3D en face analysis and MRI (r = 0.79; p<0.001; r = 0.85; p<0.001) and delta R1 (r = 0.79; p<0.001; r = 0.69; p<0.01). Conclusion GDF-enhanced in vivo MRI is a powerful non-invasive imaging technique in mice allowing for reliable estimation of atherosclerotic plaque burden, monitoring of disease progression and regression in preclinical studies. PMID:28771481

  2. Narp knockout mice show normal reactivity to novelty but attenuated recovery from neophobia.

    PubMed

    Blouin, Ashley M; Lee, Jongah J; Tao, Bo; Smith, Dani R; Johnson, Alexander W; Baraban, Jay M; Reti, Irving M

    2013-11-15

    Narp knockout (KO) mice demonstrate cognitive inflexibility and addictive behavior, which are associated with abnormal reactivity to a novel stimulus. To assess reactivity to novelty, we tested Narp KO and wild-type (WT) mice on a neophobia procedure. Both Narp KO and WT mice showed a similar decrease in consumption upon initial exposure to a novel flavor, but Narp KO mice did not increase consumption with subsequent exposures to the novel flavor like the WT mice. Therefore, Narp KO mice do not have abnormal reactivity to novelty but show deficits in adapting behavior to reflect the updated value of a stimulus. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. The Pure Rotational Spectrum of KO

    NASA Astrophysics Data System (ADS)

    Burton, Mark; Russ, Benjamin; Sheridan, Phillip M.; Bucchino, Matthew; Ziurys, Lucy M.

    2017-06-01

    The pure rotational spectrum of potassium monoxide (KO) has been recorded using millimeter-wave direct absorption spectroscopy. KO was synthesized by the reaction of potassium vapor, produced in a Broida-type oven, with nitrous oxide. No DC discharge was necessary. Eleven rotational transitions belonging to the ^{2}Π_{3/2} spin-orbit component have been measured and have been fit successfully to a case (c) Hamiltonian. Rotational and lambda-doubling constants for this spin-orbit component have been determined. It has been suggested that the ground electronic state of KO is either ^{2}Π (as for LiO and NaO) or ^{2}Σ (as for RbO and CsO), both of which lie close in energy. Recent computational studies favor a ^{2}Σ ground state. Further measurements of the rotational transitions of the ^{2}Π_{1/2} spin-orbit component and the ^{2}Σ state are currently in progress, as well as the potassium hyperfine structure.

  4. Wild Type and PPAR KO Dataset

    EPA Pesticide Factsheets

    Data set 1 consists of the experimental data for the Wild Type and PPAR KO animal study and includes data used to prepare Figures 1-4 and Table 1 of the Das et al, 2016 paper.This dataset is associated with the following publication:Das, K., C. Wood, M. Lin, A.A. Starkov, C. Lau, K.B. Wallace, C. Corton, and B. Abbott. Perfluoroalky acids-induced liver steatosis: Effects on genes controlling lipid homeostasis. TOXICOLOGY. Elsevier Science Ltd, New York, NY, USA, 378: 32-52, (2017).

  5. Sucrose-conditioned flavor preferences in sweet ageusic T1r3 and Calhm1 knockout mice

    PubMed Central

    Sclafani, Anthony; Marambaud, Philippe; Ackroff, Karen

    2014-01-01

    The present study compared the ability of sweet ageusic T1r3 knockout (KO) and Calhm1 KO mice to acquire preferences for a sucrose-paired flavor as well as for unflavored sucrose. The KO and wildtype (WT) mice were given 24-h one-bottle access to 8% sucrose containing one flavor (CS+, e.g., grape) and to water containing a different flavor (CS-, e.g., cherry) over 4 training days. In subsequent two-bottle tests with the flavors in water only, the T1r3 KO and Calhm1 KO mice, like WT mice, preferred the CS+ to the CS-. After training with flavored solutions, both KO groups also preferred unflavored 8% sucrose to water although Calhm1 KO mice required more sugar experience to match the preference of the T1r3 KO mice. These findings demonstrate that Calhm1 KO mice, like T1r3 KO mice and WT mice, are sensitive to the post-oral preference conditioning actions of sucrose and can discriminate sugar from water. Yet, despite their acquired sucrose preferences, the Calhm1 KO and T1r3 KO mice consumed only half as much sugar per day as did WT mice. Thus, sweet taste signaling elements are not needed in the gut for sugar conditioning, but sweet taste signaling in the mouth is essential for the full expression of sugar appetite. PMID:24384370

  6. Sucrose-conditioned flavor preferences in sweet ageusic T1r3 and Calhm1 knockout mice.

    PubMed

    Sclafani, Anthony; Marambaud, Philippe; Ackroff, Karen

    2014-03-14

    The present study compared the ability of sweet ageusic T1r3 knockout (KO) and Calhm1 KO mice to acquire preferences for a sucrose-paired flavor as well as for unflavored sucrose. The KO and wildtype (WT) mice were given 24-h one-bottle access to 8% sucrose containing one flavor CS+, e.g., grape) and to water containing a different flavor (CS-, e.g., cherry) over 4 training days. In subsequent two-bottle tests with the flavors in water only, the T1r3 KO and Calhm1 KO mice, like WT mice, preferred the CS+ to the CS-. After training with flavored solutions, both KO groups also preferred unflavored 8% sucrose to water although Calhm1 KO mice required more sugar experience to match the preference of the T1r3 KO mice. These findings demonstrate that Calhm1 KO mice, like T1r3 KO mice and WT mice, are sensitive to the post-oral preference conditioning actions of sucrose and can discriminate sugar from water. Yet, despite their acquired sucrose preferences, the Calhm1 KO and T1r3 KO mice consumed only half as much sugar per day as did WT mice. Thus, sweet taste signaling elements are not needed in the gut for sugar conditioning, but sweet taste signaling in the mouth is essential for the full expression of sugar appetite. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Urinary bladder hypertrophy characteristic of male ROMK Bartter's mice does not occur in female mice.

    PubMed

    Kim, Jun-Mo; Xu, Shuhua; Guo, Xiaoyun; Hu, Haiyan; Dong, Ke; Wang, Tong

    2018-03-01

    The renal outer medullary potassium channel (ROMK; K ir 1.1) plays an important role in Na + and K + homeostasis. ROMK knockout (KO) mice show a similar phenotype to Bartter's syndrome of salt wasting and dehydration due to reduced Na-2Cl-K-cotransporter activity but not in ROMK1 KO mice. ROMK KO mice also show hydronephrosis; however, the mechanism of this phenotype has not been understood. We have previously demonstrated a gender-sex difference in hydronephrosis and PGE 2 production in ROMK KO mice. In this study we compared the gender-sex difference in bladder hypertrophy and hydronephrosis in ROMK KO mice. The bladder weight, bladder capacity, and the thickness of urothelium in male ROMK KO showed average increased two to approximately fourfold greater than wild-type (WT) mice, but there was no difference in either female or ROMK1 KO mice. The thickness of the urothelium was 648.8 ± 33.2 µm vs. 302.7 ± 16.5 µm ( P < 0.001) and the detrusor muscle 1,940.7 ± 98.9 µm vs. 1,308.2 ± 102.1 µm ( P = 0.013), respectively, in 12-mo male ROMK KO mice compared with the same age WT mice. Western blotting detected ROMK expression at 45~48 kDa, and both ROMK1 and ROMK2 mRNA were detected by quantitative PCR in the bladder. Immunofluorescence staining showed ROMK stained in the bladder, ureter, and urethra in WT but not in KO. In addition, there was a correlation between the severity of hydronephrosis and the bladder weight in male but not in female ROMK KO mice. In conclusion, ROMK expressed in the urinary tract at both protein and mRNA levels; significant enlargement and hypertrophy of the bladder may contribute to hydronephrosis in male ROMK KO mice.

  8. Deciphering caveolar functions by syndapin III KO-mediated impairment of caveolar invagination

    PubMed Central

    Krueger, Sarah; Tröger, Jessica; Hou, Wenya; Haag, Natja; Schüler, Susann; Westermann, Martin; Huebner, Christian A; Romeike, Bernd

    2017-01-01

    Several human diseases are associated with a lack of caveolae. Yet, the functions of caveolae and the molecular mechanisms critical for shaping them still are debated. We show that muscle cells of syndapin III KO mice show severe reductions of caveolae reminiscent of human caveolinopathies. Yet, different from other mouse models, the levels of the plasma membrane-associated caveolar coat proteins caveolin3 and cavin1 were both not reduced upon syndapin III KO. This allowed for dissecting bona fide caveolar functions from those supported by mere caveolin presence and also demonstrated that neither caveolin3 nor caveolin3 and cavin1 are sufficient to form caveolae. The membrane-shaping protein syndapin III is crucial for caveolar invagination and KO rendered the cells sensitive to membrane tensions. Consistent with this physiological role of caveolae in counterpoising membrane tensions, syndapin III KO skeletal muscles showed pathological parameters upon physical exercise that are also found in CAVEOLIN3 mutation-associated muscle diseases. PMID:29202928

  9. Flight Tests of the KO-1 Aircraft at Night

    NASA Astrophysics Data System (ADS)

    Kwon, Jong-Kwang; Kim, Whan-Woo

    The KO-1 aircraft which has the functionality of tactical observation, was successfully developed in August of 2004 in South Korea. It is important for the KO-1 aircraft to achieve successful missions at nighttime as well as during daytime. The aircraft, equipped with interior and exterior lighting systems and lighting control panel modified from those of the KT-1 basic trainer, provides improved safety, operational effectiveness, and situational awareness during operation at night when used with night-vision goggles (NVGs). KO-1 is the first domestic aircraft that utilizes the night-vision imaging system (NVIS) technology in Korea. KO-1 NVIS was developed with the goal of defining the components of NVIS and establishing test and evaluation procedures for both the subsystems and main system. In this paper, we present the establishment of a KO-1 NVIS lighting system, NVIS component development, and representative ground and flight test results.

  10. Fractalkine (CX3CL1) enhances hippocampal N-methyl-d-aspartate receptor (NMDAR) function via d-serine and adenosine receptor type A2 (A2AR) activity

    PubMed Central

    2013-01-01

    Background N-Methyl-d-aspartate receptors (NMDARs) play fundamental roles in basic brain functions such as excitatory neurotransmission and learning and memory processes. Their function is largely regulated by factors released by glial cells, including the coagonist d-serine. We investigated whether the activation of microglial CX3CR1 induces the release of factors that modulate NMDAR functions. Methods We recorded the NMDAR component of the field excitatory postsynaptic potentials (NMDA-fEPSPs) elicited in the CA1 stratum radiatum of mouse hippocampal slices by Shaffer collateral stimulation and evaluated d-serine content in the extracellular medium of glial primary cultures by mass spectrometry analysis. Results We demonstrated that CX3CL1 increases NMDA-fEPSPs by a mechanism involving the activity of the adenosine receptor type A2 (A2AR) and the release of the NMDAR coagonist d-serine. Specifically (1) the selective A2AR blocker 7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidine (SCH58261) and the genetic ablation of A2AR prevent CX3CL1 action while the A2AR agonist 5-(6-amino-2-(phenethylthio)-9H-purin-9-yl)-N-ethyl-3,4-dihydroxytetrahydrofuran-2-carboxamide (VT7) mimics CX3CL1 effect, and (2) the selective blocking of the NMDAR glycine (and d-serine) site by 5,7-dicholorokynurenic acid (DCKA), the enzymatic degradation of d-serine by d-amino acid oxidase (DAAO) and the saturation of the coagonist site by d-serine, all block the CX3CL1 effect. In addition, mass spectrometry analysis demonstrates that stimulation of microglia and astrocytes with CX3CL1 or VT7 increases d-serine release in the extracellular medium. Conclusions CX3CL1 transiently potentiates NMDAR function though mechanisms involving A2AR activity and the release of d-serine. PMID:23981568

  11. DSTYK kinase domain ablation impaired the mice capabilities of learning and memory in water maze test.

    PubMed

    Li, Kui; Liu, Ji-Wei; Zhu, Zhi-Chuan; Wang, Hong-Tao; Zu, Yong; Liu, Yong-Jie; Yang, Yan-Hong; Xiong, Zhi-Qi; Shen, Xu; Chen, Rui; Zheng, Jing; Hu, Ze-Lan

    2014-01-01

    DSTYK (Dual serine/threonine and tyrosine protein kinase) is a putative dual Ser/Thr and Tyr protein kinase with unique structural features. It is proposed that DSTYK may play important roles in brain because of its high expression in most brain areas. In the present study, a DSTYK knockout (KO) mouse line with the ablation of C-terminal of DSTYK including the kinase domain was generated to study the physiological function of DSTYK. The DSTYK KO mice are fertile and have no significant morphological defects revealed by Nissl staining compared with wildtype mice. Open field test and rotarod test showed there is no obvious difference in basic motor and balance capacity between the DSTYK homozygous KO mice and DSTYK heterozygous KO mice. In water maze test, however, the DSTYK homozygous KO mice show impaired capabilities of learning and memory compared with the DSTYK heterozygous KO mice.

  12. Serum CTX levels and histomorphometric analysis in Src versus RANKL knockout mice.

    PubMed

    Takeshita, Sunao; Fumoto, Toshio; Ito, Masako; Ikeda, Kyoji

    2017-06-06

    Src knockout (KO) and RANKL KO mice both exhibit near complete osteopetrosis in terms of 3D-bone volume (BV) fraction by micro-CT, whereas the serum CTX concentration of Src KO is apparently normal and that of RANKL KO is 30% of wild-type (WT) despite the fact that they lack osteoclasts. By histomorphometry we found that, whereas eroded surface (ES) and osteoid surface (OS) are zero values in RANKL KO, they are indistinguishable from WT in Src KO; because of marked increase in bone surface (BS), ES/BS and OS/BS of Src KO are 30-40% of WT. While RANKL KO lack both osteoclasts and osteoblasts, Src KO reveal increased numbers of osteoclasts and indistinguishable numbers of osteoblasts compared with WT; again, on the basis of BS, N.Oc/BS is comparable to WT and N.Ob/BS is markedly decreased in Src KO. The apparently increased number of total osteoclasts may be due to increased expression of RANKL found in Src KO bone in vivo. Src has a gene dosage-dependent effect on osteoclast function in vitro, with Src -/- osteoclasts completely lacking bone-resorbing function as determined by CTX release on dentin. Thus, Src KO osteoclasts retain some bone-resorbing function in vivo. The number of osteocytes is proportionally increased in RANKL KO, while Src KO mice have relative osteocyte deficiency, raising the possibility that RANKL and Src has an unrecognized role in osteocyte survival.

  13. Vasoactive Intestinal Peptide Knockout (VIP KO) mouse model of sulfite-sensitive asthma: up-regulation of novel lung carbonyl reductase.

    PubMed

    Szema, Anthony M; Hamidi, Sayyed A; Koller, Antonius; Martin, Dwight W

    2011-11-21

    We earlier reported spontaneous features of asthma in Vasoactive Intestinal Peptide knockout mice (VIP KO): 1) peribronchiolar airway inflammation, with accumulation of lymphocytes and eosinophils, 2) pro-inflammatory cytokine production of IL-5, IL-6, with IFN-γ, and 3) airway hyper-responsiveness to inhaled methacholine. In human asthma, a phenotype with sulfite sensitivity leads to airway inflammation and hyper-responsiveness to inhaled sulfites, and is associated with upregulation of anti-oxidant protein lung carbonyl reductase. For the present experiments, we examined the role of VIP in modulating anti-oxidant genes and their proteins, including lung carbonyl reductase. Four male VIP KO mice and four wild-type age- and gender matched mice had lungs examined for whole genome microarray and a proteomics approach using mass spectrometry. The proteomics analysis revealed that a novel variant of anti-oxidant protein lung carbonyl reductase (car3) was uniquely and markedly elevated in the VIP KO mice. RT-PCR indicated that carbonic anhydrase 3, which is an anti-oxidant protein, was elevated in the VIP KO mice. These data support the concept that VIP influences the endogenous oxidant/antioxidant balance. One potential implication is that VIP and its analogues may be used to treat inflammatory diseases, including asthma.

  14. Vasoactive Intestinal Peptide Knockout (VIP KO) mouse model of sulfite-sensitive asthma: up-regulation of novel lung carbonyl reductase

    PubMed Central

    2011-01-01

    Background We earlier reported spontaneous features of asthma in Vasoactive Intestinal Peptide knockout mice (VIP KO): 1) peribronchiolar airway inflammation, with accumulation of lymphocytes and eosinophils, 2) pro-inflammatory cytokine production of IL-5, IL-6, with IFN-γ, and 3) airway hyper-responsiveness to inhaled methacholine. In human asthma, a phenotype with sulfite sensitivity leads to airway inflammation and hyper-responsiveness to inhaled sulfites, and is associated with upregulation of anti-oxidant protein lung carbonyl reductase. For the present experiments, we examined the role of VIP in modulating anti-oxidant genes and their proteins, including lung carbonyl reductase. Results Four male VIP KO mice and four wild-type age- and gender matched mice had lungs examined for whole genome microarray and a proteomics approach using mass spectrometry. The proteomics analysis revealed that a novel variant of anti-oxidant protein lung carbonyl reductase (car3) was uniquely and markedly elevated in the VIP KO mice. RT-PCR indicated that carbonic anhydrase 3, which is an anti-oxidant protein, was elevated in the VIP KO mice. Conclusions These data support the concept that VIP influences the endogenous oxidant/antioxidant balance. One potential implication is that VIP and its analogues may be used to treat inflammatory diseases, including asthma. PMID:22103391

  15. Balance of meprin A and B in mice affects the progression of experimental inflammatory bowel disease.

    PubMed

    Banerjee, Sanjita; Jin, Ge; Bradley, S Gaylen; Matters, Gail L; Gailey, Ryan D; Crisman, Jacqueline M; Bond, Judith S

    2011-02-01

    MEP1A, which encodes the α subunit of meprin metalloproteinases, is a susceptibility gene for inflammatory bowel disease (IBD), and decreased intestinal meprin-α expression is associated with enhanced IBD in humans. Mice lacking meprin α (α knockout, αKO) have more severe colitis induced by dextran sulfate sodium (DSS) than wild-type (WT) mice, indicating an anti-inflammatory role for meprin A. Previous studies and those herein indicate the meprin B has proinflammatory activities. Therefore, mice lacking both meprin A and B (dKO mice) were generated to determine how their combined absence alters the inflammatory response to DSS. Unchallenged dKO mice grow and reproduce normally and have no obvious abnormal phenotype, except for a slightly elevated plasma albumin in both males and females and a lower urine creatinine level in dKO males. Upon oral administration of 3.5% DSS, the dKO mice have more severe colitis than the WT and βKO mice but significantly less than the αKO mice. The dKO mice lose more weight and have elevated MPO and IL-6 activities in the colon compared with WT mice. Systemic inflammation, monitored by plasma nitric oxide levels, is absent in DSS-treated dKO mice, unlike WT mice. The severity of experimental IBD in dKO mice is intermediate between αKO and WT mice. The data indicate that the absence of meprin A aggravates chronic inflammation and the lack of meprin B affords some protection from injury. Manipulation of the expression of meprin gene products may have therapeutic potential.

  16. Balance of meprin A and B in mice affects the progression of experimental inflammatory bowel disease

    PubMed Central

    Banerjee, Sanjita; Jin, Ge; Bradley, S. Gaylen; Matters, Gail L.; Gailey, Ryan D.; Crisman, Jacqueline M.

    2011-01-01

    MEP1A, which encodes the α subunit of meprin metalloproteinases, is a susceptibility gene for inflammatory bowel disease (IBD), and decreased intestinal meprin-α expression is associated with enhanced IBD in humans. Mice lacking meprin α (α knockout, αKO) have more severe colitis induced by dextran sulfate sodium (DSS) than wild-type (WT) mice, indicating an anti-inflammatory role for meprin A. Previous studies and those herein indicate the meprin B has proinflammatory activities. Therefore, mice lacking both meprin A and B (dKO mice) were generated to determine how their combined absence alters the inflammatory response to DSS. Unchallenged dKO mice grow and reproduce normally and have no obvious abnormal phenotype, except for a slightly elevated plasma albumin in both males and females and a lower urine creatinine level in dKO males. Upon oral administration of 3.5% DSS, the dKO mice have more severe colitis than the WT and βKO mice but significantly less than the αKO mice. The dKO mice lose more weight and have elevated MPO and IL-6 activities in the colon compared with WT mice. Systemic inflammation, monitored by plasma nitric oxide levels, is absent in DSS-treated dKO mice, unlike WT mice. The severity of experimental IBD in dKO mice is intermediate between αKO and WT mice. The data indicate that the absence of meprin A aggravates chronic inflammation and the lack of meprin B affords some protection from injury. Manipulation of the expression of meprin gene products may have therapeutic potential. PMID:21071511

  17. Analysis of metabolic effects of menthol on WFS1-deficient mice.

    PubMed

    Ehrlich, Marite; Ivask, Marilin; Raasmaja, Atso; Kõks, Sulev

    2016-01-01

    In this study, we investigated the physiological regulation of energy metabolism in wild-type (WT) and WFS1-deficient (Wfs1KO) mice by measuring the effects of menthol treatment on the O2 consumption, CO2 production, rectal body temperature, and heat production. The basal metabolism and behavior was different between these genotypes as well as TRP family gene expressions. Wfs1KO mice had a shorter life span and weighed less than WT mice. The food and water intake of Wfs1KO mice was lower as well as the body temperature when compared to their WT littermates. Furthermore, Wfs1KO mice had higher basal O2 consumption, and CO2 and heat production than WT mice. In addition, Wfs1KO mice showed a higher response to menthol administration in comparison to WT mice. The strongest menthol effect was seen on different physiological measures 12 h after oral administration. The highest metabolic response of Wfs1KO mice was seen at the menthol dose of 10 mg/kg. Menthol increased O2 consumption, and CO2 and heat production in Wfs1KO mice when compared to their WT littermates. In addition, the expression of Trpm8 gene was increased. In conclusion, our results show that the Wfs1KO mice develop a metabolic phenotype characterized with several physiological dysfunctions. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  18. 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

  19. Predicting Maps of Green Growth in Košice

    NASA Astrophysics Data System (ADS)

    Poorova, Zuzana; Vranayova, Zuzana

    2017-10-01

    The paper deals with the changing of the traditional roofs in the city of Košice into green roofs. Possible areas of city housing estates, after taking into account the conditions of each of them (types of buildings, statics of buildings), are listed in the paper. The research is picturing the prediction maps of Košice city from 2017 to 2042 in 5-years interval. The paper is a segment of a dissertation work focusing on changing traditional roofs into green roofs with the aim to retain water, calculate the amount of retained water and show possibilities how to use this water.

  20. 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.

  1. An Essential Physiological Role for MCT8 in Bone in Male Mice

    PubMed Central

    Leitch, Victoria D.; Di Cosmo, Caterina; Liao, Xiao-Hui; O’Boy, Sam; Galliford, Thomas M.; Evans, Holly; Croucher, Peter I.; Boyde, Alan; Dumitrescu, Alexandra; Weiss, Roy E.; Refetoff, Samuel; Williams, Graham R.

    2017-01-01

    T3 is an important regulator of skeletal development and adult bone maintenance. Thyroid hormone action requires efficient transport of T4 and T3 into target cells. We hypothesized that monocarboxylate transporter (MCT) 8, encoded by Mct8 on the X-chromosome, is an essential thyroid hormone transporter in bone. To test this hypothesis, we determined the juvenile and adult skeletal phenotypes of male Mct8 knockout mice (Mct8KO) and Mct8D1D2KO compound mutants, which additionally lack the ability to convert the prohormone T4 to the active hormone T3. Prenatal skeletal development was normal in both Mct8KO and Mct8D1D2KO mice, whereas postnatal endochondral ossification and linear growth were delayed in both Mct8KO and Mct8D1D2KO mice. Furthermore, bone mass and mineralization were decreased in adult Mct8KO and Mct8D1D2KO mice, and compound mutants also had reduced bone strength. Delayed bone development and maturation in Mct8KO and Mct8D1D2KO mice is consistent with decreased thyroid hormone action in growth plate chondrocytes despite elevated serum T3 concentrations, whereas low bone mass and osteoporosis reflects increased thyroid hormone action in adult bone due to elevated systemic T3 levels. These studies identify an essential physiological requirement for MCT8 in chondrocytes, and demonstrate a role for additional transporters in other skeletal cells during adult bone maintenance. PMID:28637283

  2. An Essential Physiological Role for MCT8 in Bone in Male Mice.

    PubMed

    Leitch, Victoria D; Di Cosmo, Caterina; Liao, Xiao-Hui; O'Boy, Sam; Galliford, Thomas M; Evans, Holly; Croucher, Peter I; Boyde, Alan; Dumitrescu, Alexandra; Weiss, Roy E; Refetoff, Samuel; Williams, Graham R; Bassett, J H Duncan

    2017-09-01

    T3 is an important regulator of skeletal development and adult bone maintenance. Thyroid hormone action requires efficient transport of T4 and T3 into target cells. We hypothesized that monocarboxylate transporter (MCT) 8, encoded by Mct8 on the X-chromosome, is an essential thyroid hormone transporter in bone. To test this hypothesis, we determined the juvenile and adult skeletal phenotypes of male Mct8 knockout mice (Mct8KO) and Mct8D1D2KO compound mutants, which additionally lack the ability to convert the prohormone T4 to the active hormone T3. Prenatal skeletal development was normal in both Mct8KO and Mct8D1D2KO mice, whereas postnatal endochondral ossification and linear growth were delayed in both Mct8KO and Mct8D1D2KO mice. Furthermore, bone mass and mineralization were decreased in adult Mct8KO and Mct8D1D2KO mice, and compound mutants also had reduced bone strength. Delayed bone development and maturation in Mct8KO and Mct8D1D2KO mice is consistent with decreased thyroid hormone action in growth plate chondrocytes despite elevated serum T3 concentrations, whereas low bone mass and osteoporosis reflects increased thyroid hormone action in adult bone due to elevated systemic T3 levels. These studies identify an essential physiological requirement for MCT8 in chondrocytes, and demonstrate a role for additional transporters in other skeletal cells during adult bone maintenance.

  3. IL-4 Knock Out Mice Display Anxiety-Like Behavior.

    PubMed

    Moon, Morgan L; Joesting, Jennifer J; Blevins, Neil A; Lawson, Marcus A; Gainey, Stephen J; Towers, Albert E; McNeil, Leslie K; Freund, Gregory G

    2015-07-01

    Inflammation is a recognized antecedent and coincident factor when examining the biology of anxiety. Little is known, however, about how reductions in endogenous anti-inflammatory mediators impact anxiety. Therefore, mood- cognition- and anxiety-associated/like behaviors were examined in IL-4 knock out (KO) mice and wild-type (WT) mice. In comparison to WT mice, IL-4 KO mice demonstrated decreased burrowing and increased social exploration. No differences were seen in forced swim or saccharine preference testing. IL-4 KO mice had similar performance to WT mice in the Morris water maze and during object location and novel object recognition. In the elevated zero-maze, IL-4 KO mice, in comparison to WT mice, demonstrated anxiety-like behavior. Anxiety-like behavior in IL-4 KO mice was not observed, however, during open-field testing. Taken together, these data indicate that IL-4 KO mice display state, but not trait, anxiety suggesting that reductions in endogenous anti-inflammatory bioactives can engender subtypes of anxiety.

  4. Sociophonetic Variations in Korean Constituent Final "-Ko" and "-To"

    ERIC Educational Resources Information Center

    Yi, So Young L.

    2015-01-01

    The purpose of this dissertation is to examine (i) linguistic and extralinguistic factors that influence vowel raising of /o/ in constituent-final "-ko" and "-to" in Seoul Korean and (ii) listeners' perceptions of this vowel raising and social meanings of the raised variant. The analyses are based on production data collected…

  5. Contribution of PPARγ in modulation of acrolein-induced inflammatory signaling in gp91phox knock-out mice.

    PubMed

    Yousefipour, Zivar; Chug, Neha; Marek, Katarzyna; Nesbary, Alicia; Mathew, Joseph; Ranganna, Kasturi; Newaz, Mohammad A

    2017-08-01

    Oxidative stress and inflammation are major contributors to acrolein toxicity. Peroxisome proliferator activated receptor gamma (PPARγ) has antioxidant and anti-inflammatory effects. We investigated the contribution of PPARγ ligand GW1929 to the attenuation of oxidative stress in acrolein-induced insult. Male gp91 phox knock-out (KO) mice were treated with acrolein (0.5 mg·(kg body mass) -1 by intraperitoneal injection for 7 days) with or without GW1929 (GW; 0.5 mg·(kg body mass) -1 ·day -1 , orally, for 10 days). The livers were processed for further analyses. Acrolein significantly increased 8-isoprostane and reduced PPARγ activity (P < 0.05) in the wild type (WT) and KO mice. GW1929 reduced 8-isoprostane (by 32% and 40% in WT and KO mice, respectively) and increased PPARγ activity (by 81% and 92% in WT and KO, respectively). Chemokine activity was increased (by 63%) in acrolein-treated WT mice, and was reduced by GW1929 (by 65%). KO mice exhibited higher xanthine oxidase (XO). Acrolein increased XO and COX in WT mice and XO in KO mice. GW1929 significantly reduced COX in WT and KO mice and reduced XO in KO mice. Acrolein significantly reduced the total antioxidant status in WT and KO mice (P < 0.05), which was improved by GW1929 (by 75% and 74%). The levels of NF-κB were higher in acrolein-treated WT mice. GW1929 reduced NF-κB levels (by 51%) in KO mice. Acrolein increased CD36 in KO mice (by 43%), which was blunted with GW1929. Data confirms that the generation of free radicals by acrolein is mainly through NAD(P)H, but other oxygenates play a role too. GW1929 may alleviate the toxicity of acrolein by attenuating NF-κB, COX, and CD36.

  6. Muscarinic acetylcholine receptor knockout mice show distinct synaptic plasticity impairments in the visual cortex

    PubMed Central

    Origlia, Nicola; Kuczewski, Nicola; Aztiria, Eugenio; Gautam, Dinesh; Wess, Jürgen; Domenici, Luciano

    2006-01-01

    In the present report, we focused our attention on the role played by the muscarinic acetylcholine receptors (mAChRs) in different forms of long-term synaptic plasticity. Specifically, we investigated long-term potentiation (LTP) and long-term depression (LTD) expression elicited by theta-burst stimulation (TBS) and low-frequency stimulation (LFS), respectively, in visual cortical slices obtained from different mAChR knockout (KO) mice. A normal LTP was evoked in M1/M3 double KO mice, while LTP was impaired in the M2/M4 double KO animals. On the other hand, LFS induced LTD in M2/M4 double KO mice, but failed to do so in M1/M3 KO mice. Interestingly, LFS produced LTP instead of LTD in M1/M3 KO mice. Analysis of mAChR single KO mice revealed that LTP was affected only by the simultaneous absence of both M2 and M4 receptors. A LFS-dependent shift from LTD to LTP was also observed in slices from M1 KO mice, while LTD was simply abolished in slices from M3 KO mice. Using pharmacological tools, we showed that LTP in control mice was blocked by pertussis toxin, an inhibitor of Gi/o proteins, but not by raising intracellular cAMP levels. In addition, the inhibition of phospholipase C by U73122 induced the same shift from LTD to LTP after LFS observed in M1 single KO and M1/M3 double KO mice. Our results indicate that different mAChR subtypes regulate different forms of long-term synaptic plasticity in the mouse visual cortex, activating specific G proteins and downstream intracellular mechanisms. PMID:17023506

  7. Macrophage Adipose Triglyceride Lipase Deficiency Attenuates Atherosclerotic Lesion Development in Low-Density Lipoprotein Receptor Knockout Mice

    PubMed Central

    Lammers, Bart; Chandak, Prakash G.; Aflaki, Elma; Van Puijvelde, Gijs H.M.; Radovic, Branislav; Hildebrand, Reeni B.; Meurs, Illiana; Out, Ruud; Kuiper, Johan; Van Berkel, Theo J.C.; Kolb, Dagmar; Haemmerle, Guenter; Zechner, Rudolf; Levak-Frank, Sanja; Van Eck, Miranda; Kratky, Dagmar

    2011-01-01

    Objective The consequences of macrophage triglyceride (TG) accumulation on atherosclerosis have not been studied in detail so far. Adipose triglyceride lipase (ATGL) is the rate-limiting enzyme for the initial step in TG hydrolysis. Because ATGL knockout (KO) mice exhibit massive TG accumulation in macrophages, we used ATGL KO mice to study the effects of macrophage TG accumulation on atherogenesis. Methods and Results Low-density lipoprotein receptor (LDLr) KO mice were transplanted with bone marrow from ATGL KO (ATGL KO→LDLr KO) or wild-type (wild-type→LDLr KO) mice and challenged with a Western-type diet for 9 weeks. Despite TG accumulation in ATGL KO macrophages, atherosclerosis in ATGL KO→LDLr KO mice was 43% reduced associated with decreased plasma MCP-1 and macrophage interleukin-6 concentrations. This coincided with a reduced amount of macrophages, possibly because of a 39% increase in intraplaque apoptosis and a decreased migratory capacity of ATGL KO macrophages. The reduced number of white blood cells might be due to a 36% decreased Lin−Sca-1+cKit+ hematopoietic stem cell population. Conclusion We conclude that the attenuation of atherogenesis in ATGL KO→LDLr KO mice is due to decreased infiltration of less inflammatory macrophages into the arterial wall and increased macrophage apoptosis. PMID:21030715

  8. Fus1 KO Mouse As a Model of Oxidative Stress-Mediated Sporadic Alzheimer's Disease: Circadian Disruption and Long-Term Spatial and Olfactory Memory Impairments

    PubMed Central

    Coronas-Samano, Guillermo; Baker, Keeley L.; Tan, Winston J. T.; Ivanova, Alla V.; Verhagen, Justus V.

    2016-01-01

    Insufficient advances in the development of effective therapeutic treatments of sporadic Alzheimer's Disease (sAD) to date are largely due to the lack of sAD-relevant animal models. While the vast majority of models do recapitulate AD's hallmarks of plaques and tangles by virtue of tau and/or beta amyloid overexpression, these models do not reflect the fact that in sAD (unlike familial AD) these genes are not risk factors per se and that other mechanisms like oxidative stress, metabolic dysregulation and inflammation play key roles in AD etiology. Here we characterize and propose the Fus1 KO mice that lack a mitochondrial protein Fus1/Tusc2 as a new sAD model. To establish sAD relevance, we assessed sAD related deficits in Fus1 KO and WT adult mice of 4–5 months old, the equivalent human age when the earliest cognitive and olfactory sAD symptoms arise. Fus1 KO mice showed oxidative stress (increased levels of ROS, decreased levels of PRDX1), disruption of metabolic homeostasis (decreased levels of ACC2, increased phosphorylation of AMPK), autophagy (decreased levels of LC3-II), PKC (decreased levels of RACK1) and calcium signaling (decreased levels of Calb2) in the olfactory bulb and/or hippocampus. Mice were behaviorally tested using objective and accurate video tracking (Noldus), in which Fus1 KO mice showed clear deficits in olfactory memory (decreased habituation/cross-habituation in the short and long term), olfactory guided navigation memory (inability to reduce their latency to find the hidden cookie), spatial memory (learning impairments on finding the platform in the Morris water maze) and showed more sleep time during the diurnal cycle. Fus1 KO mice did not show clear deficits in olfactory perception (cross-habituation), association memory (passive avoidance) or in species-typical behavior (nest building) and no increased anxiety (open field, light-dark box) or depression/anhedonia (sucrose preference) at this relatively young age. These neurobehavioral

  9. Evaluation of seasonal influenza vaccines for H1N1pdm09 and type B viruses based on a replication-incompetent PB2-KO virus.

    PubMed

    Ui, Hiroki; Yamayoshi, Seiya; Uraki, Ryuta; Kiso, Maki; Oishi, Kohei; Murakami, Shin; Mimori, Shigetaka; Kawaoka, Yoshihiro

    2017-04-04

    Vaccination is the first line of protection against influenza virus infection in humans. Although inactivated and live-attenuated vaccines are available, each vaccine has drawbacks in terms of immunogenicity and safety. To overcome these issues, our group has developed a replication-incompetent PB2-knockout (PB2-KO) influenza virus that replicates only in PB2-expressing cells. Here we generated PB2-KO viruses possessing the hemagglutinin (HA) and neuraminidase (NA) segments from H1N1pdm09 or type B viruses and tested their vaccine potential. The two PB2-KO viruses propagated efficiently in PB2-expressing cells, and expressed chimeric HA as expected. Virus-specific IgG and IgA antibodies were detected in mice immunized with the viruses, and the immunized mice showed milder clinical signs and/or lower virus replication levels in the respiratory tract upon virus challenge. Our results indicate that these PB2-KO viruses have potential as vaccine candidates. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Crucial roles of nitric oxide synthases in β-adrenoceptor-mediated bladder relaxation in mice.

    PubMed

    Satake, Yohei; Satoh, Kimio; Nogi, Masamichi; Omura, Junichi; Godo, Shigeo; Miyata, Satoshi; Saito, Hiroki; Tanaka, Shuhei; Ikumi, Yosuke; Yamashita, Shinichi; Kaiho, Yasuhiro; Tsutsui, Masato; Arai, Yoichi; Shimokawa, Hiroaki

    2017-01-01

    The specific roles of nitric oxide (NO) synthases (NOSs) in bladder smooth muscle remain to be elucidated. We examined the roles of NOSs in β-adrenoceptor (AR)-mediated bladder relaxation. Male mice (C57BL6) deficient of neuronal NOS [nNOS-knockout (KO)], endothelial NOS (eNOS-KO), neuronal/endothelial NOS (n/eNOS-KO), neuronal/endothelial/inducible NOS (n/e/iNOS-KO), and their controls [wild-type (WT)] were used. Immunohistochemical analysis was performed in the bladder. Then the responses to relaxing agents and the effects of several inhibitors on the relaxing responses were examined in bladder strips precontracted with carbachol. Immunofluorescence staining showed expressions of nNOS and eNOS in the urothelium and smooth muscle of the bladder. Isoproterenol-induced relaxations were significantly reduced in nNOS-KO mice and were further reduced in n/eNOS-KO and n/e/iNOS-KO mice compared with WT mice. The relaxation in n/e/iNOS-KO mice was almost the same as in n/eNOS-KO mice. Inhibition of Ca 2+ -activated K + (K Ca ) channel with charybdotoxin and apamin abolished isoproterenol-induced bladder relaxation in WT mice. Moreover, direct activation of K Ca channel with NS1619 caused comparable extent of relaxations among WT, nNOS-KO, and n/eNOS-KO mice. In contrast, NONOate (a NO donor) or hydrogen peroxide (H 2 O 2 ) (another possible relaxing factor from eNOS) caused minimal relaxations, and catalase (H 2 O 2 scavenger) had no inhibitory effects on isoproterenol-induced relaxations. These results indicate that both nNOS and eNOS are substantially involved in β-AR-mediated bladder relaxations in a NO- or H 2 O 2 -independent manner through activation of K Ca channels. Copyright © 2017 the American Physiological Society.

  11. Calcineurin knockout mice show a selective loss of small spines.

    PubMed

    Okazaki, Hitoshi; Hayashi-Takagi, Akiko; Nagaoka, Akira; Negishi, Makiko; Ucar, Hasan; Yagishita, Sho; Ishii, Kazuhiko; Toyoizumi, Taro; Fox, Kevin; Kasai, Haruo

    2018-04-03

    Calcineurin is required for long-term depression and activity-dependent spine shrinkage, and calcineurin mutations have been identified in patients with schizophrenia. Moreover, mice with conditional knockout of calcineurin B (CNB-KO) exhibit behavioral abnormalities suggestive of schizophrenia. Changes in the dendritic spines of these mice, however, have not been investigated. We therefore examined the dendritic spines of CNB-KO mice, and observed a significant reduction in small spines and an increase in large spines in the prefrontal and visual cortices. The effect of CNB-KO on the spine sizes was relatively moderate, possibly due to the presence of spontaneous fluctuations (dynamics) in the dendritic spines themselves. Thus, CNB-KO mice showed a spine phenotype similar to those recently reported in patients with schizophrenia. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

  12. Cyclooxygenase-2 Suppresses the Anabolic Response to PTH Infusion in Mice

    PubMed Central

    Choudhary, Shilpa; Canalis, Ernesto; Estus, Thomas; Adams, Douglas; Pilbeam, Carol

    2015-01-01

    We previously reported that the ability of continuously elevated PTH to stimulate osteoblastic differentiation in bone marrow stromal cell cultures was abrogated by an osteoclastic factor secreted in response to cyclooxygenase-2 (Cox2)-produced prostaglandin E2. We now examine the impact of Cox2 (Ptgs2) knockout (KO) on the anabolic response to continuously elevated PTH in vivo. PTH (40 μg/kg/d) or vehicle was infused for 12 or 21 days in 3-mo-old male wild type (WT) and KO mice in the outbred CD-1 background. Changes in bone phenotype were assessed by bone mineral density (BMD), μCT and histomorphometry. PTH infusion for both 12 and 21 days increased femoral BMD in Cox2 KO mice and decreased BMD in WT mice. Femoral and vertebral trabecular bone volume fractions were increased in KO mice, but not in WT mice, by PTH infusion. In the femoral diaphysis, PTH infusion increased cortical area in Cox2 KO, but not WT, femurs. PTH infusion markedly increased trabecular bone formation rate in the femur, serum markers of bone formation, and expression of bone formation-related genes, growth factors, and Wnt target genes in KO mice relative to WT mice, and decreased gene expression of Wnt antagonists only in KO mice. In contrast to the differential effects of PTH on anabolic factors in WT and KO mice, PTH infusion increased serum markers of resorption, expression of resorption-related genes, and the percent bone surface covered by osteoclasts similarly in both WT and KO mice. We conclude that Cox2 inhibits the anabolic, but not the catabolic, effects of continuous PTH. These data suggest that the bone loss with continuously infused PTH in mice is due largely to suppression of bone formation and that this suppression is mediated by Cox2. PMID:25781979

  13. Cyclooxygenase-2 suppresses the anabolic response to PTH infusion in mice.

    PubMed

    Choudhary, Shilpa; Canalis, Ernesto; Estus, Thomas; Adams, Douglas; Pilbeam, Carol

    2015-01-01

    We previously reported that the ability of continuously elevated PTH to stimulate osteoblastic differentiation in bone marrow stromal cell cultures was abrogated by an osteoclastic factor secreted in response to cyclooxygenase-2 (Cox2)-produced prostaglandin E2. We now examine the impact of Cox2 (Ptgs2) knockout (KO) on the anabolic response to continuously elevated PTH in vivo. PTH (40 μg/kg/d) or vehicle was infused for 12 or 21 days in 3-mo-old male wild type (WT) and KO mice in the outbred CD-1 background. Changes in bone phenotype were assessed by bone mineral density (BMD), μCT and histomorphometry. PTH infusion for both 12 and 21 days increased femoral BMD in Cox2 KO mice and decreased BMD in WT mice. Femoral and vertebral trabecular bone volume fractions were increased in KO mice, but not in WT mice, by PTH infusion. In the femoral diaphysis, PTH infusion increased cortical area in Cox2 KO, but not WT, femurs. PTH infusion markedly increased trabecular bone formation rate in the femur, serum markers of bone formation, and expression of bone formation-related genes, growth factors, and Wnt target genes in KO mice relative to WT mice, and decreased gene expression of Wnt antagonists only in KO mice. In contrast to the differential effects of PTH on anabolic factors in WT and KO mice, PTH infusion increased serum markers of resorption, expression of resorption-related genes, and the percent bone surface covered by osteoclasts similarly in both WT and KO mice. We conclude that Cox2 inhibits the anabolic, but not the catabolic, effects of continuous PTH. These data suggest that the bone loss with continuously infused PTH in mice is due largely to suppression of bone formation and that this suppression is mediated by Cox2.

  14. Hepatocyte growth factor ameliorates hyperglycemia and corrects β-cell mass in IRS2-deficient mice.

    PubMed

    Alvarez-Perez, Juan C; Rosa, Taylor C; Casinelli, Gabriella P; Valle, Shelley R; Lakshmipathi, Jayalakshmi; Rosselot, Carolina; Rausell-Palamos, Francisco; Vasavada, Rupangi C; García-Ocaña, Adolfo

    2014-12-01

    Insulin resistance, when combined with decreased β-cell mass and relative insufficient insulin secretion, leads to type 2 diabetes. Mice lacking the IRS2 gene (IRS2(-/-) mice) develop diabetes due to uncompensated insulin resistance and β-cell failure. Hepatocyte growth factor (HGF) activates the phosphatidylinositol 3-kinase/Akt signaling pathway in β-cells without recruitment of IRS1 or IRS2 and increases β-cell proliferation, survival, mass, and function when overexpressed in β-cells of transgenic (TG) mice. We therefore hypothesized that HGF may protect against β-cell failure in IRS2 deficiency. For that purpose, we cross-bred TG mice overexpressing HGF in β-cells with IRS2 knockout (KO) mice. Glucose homeostasis analysis revealed significantly reduced hyperglycemia, compensatory hyperinsulinemia, and improved glucose tolerance in TG/KO mice compared with those in KO mice in the context of similar insulin resistance. HGF overexpression also increased glucose-stimulated insulin secretion in IRS2(-/-) islets. To determine whether this glucose homeostasis improvement correlated with alterations in β-cells, we measured β-cell mass, proliferation, and death in these mice. β-Cell proliferation was increased and death was decreased in TG/KO mice compared with those in KO mice. As a result, β-cell mass was significantly increased in TG/KO mice compared with that in KO mice, reaching levels similar to those in wild-type mice. Analysis of the intracellular targets involved in β-cell failure in IRS2 deficiency showed Pdx-1 up-regulation, Akt/FoxO1 phosphorylation, and p27 down-regulation in TG/KO mouse islets. Taken together, these results indicate that HGF can compensate for IRS2 deficiency and subsequent insulin resistance by normalizing β-cell mass and increasing circulating insulin. HGF may be of value as a therapeutic agent against β-cell failure.

  15. Deficient melanocortin-4 receptor causes abnormal reproductive neuroendocrine profile in female mice.

    PubMed

    Chen, Xiaolin; Huang, Lili; Tan, Hwee Y; Li, Hongzhuo; Wan, Ying; Cowley, Michael; Veldhuis, Johannes D; Chen, Chen

    2017-03-01

    Deletion of the melanocortin-4-receptor (Mc4r) gene in mice causes hyperphagia, followed by hyperinsulinemia, obesity and progressive infertility. Evidence shows that the number of developed corpora lutea is reduced in obese MC4R-knockout (MC4R KO) female mice, but the mechanism is unclear. The effect of hyperphagia and obesity by MC4R KO on pulsatile luteinizing hormone (LH) secretion and ovulation remains unknown. In MC4R KO mice and wild-type littermates (WT LM) during the diestrus period throughout different ages, we examined and monitored their metabolic status, pulsatile LH profiles, follicular morphology and the number of corpora lutea. MC4R KO mice were hyperphagic, obese, hyperglycemic, hyperinsulinemic and demonstrated insulin resistance and hepatic steatosis. Irregular estrous cycles and significant changes in the LH secretion profiles were observed in sexually matured 16- to 28-week MC4R KO mice, without any difference in testosterone levels. In addition, MC4R KO mice at 16 weeks of age had significantly fewer corpora lutea than same age WT LM mice. The ovary examinations of MC4R KO mice at 28 weeks of age showed predominantly antral and preovulatory follicles with no corpora lutea. These findings were consistent with the decrease in total, pulsatile, mass and basal LH releases in MC4R KO mice. The characteristics of hormone profiles in obese MC4R KO mice indicate that MC4R plays an important role in regulating LH release, ovulation and reproductive ability probably via hyperphagia-induced obesity. Further study of correlation between metabolic and reproductive regulatory hormones is warranted to dissect the pathological mechanism underlying obesity-induced infertility.Free Chinese abstract: A Chinese translation of this abstract is freely available at http://www.reproduction-online.org/content/153/3/267/suppl/DC1. © 2017 Society for Reproduction and Fertility.

  16. Increased glucose tolerance and reduced adiposity in the absence of fasting hypoglycemia in mice with liver-specific Gsα deficiency

    PubMed Central

    Chen, Min; Gavrilova, Oksana; Zhao, Wei-Qin; Nguyen, Annie; Lorenzo, Javier; Shen, Laura; Nackers, Lisa; Pack, Stephanie; Jou, William; Weinstein, Lee S.

    2005-01-01

    The G protein Gsα is essential for hormone-stimulated cAMP generation and is an important metabolic regulator. We investigated the role of liver Gs-signaling pathways by developing mice with liver-specific Gsα deficiency (LGsKO mice). LGsKO mice had increased liver weight and glycogen content and reduced adiposity, whereas survival, body weight, food intake, and metabolic rates at ambient temperature were unaffected. LGsKO mice had increased glucose tolerance with both increased glucose-stimulated insulin secretion and increased insulin sensitivity in liver and muscle. Fed LGsKO mice were hypoglycemic and hypoinsulinemic, with low expression of hepatic gluconeogenic enzymes and PPARγ coactivator–1. However, LGsKO mice maintained normal fasting glucose and insulin levels, probably due to prolonged breakdown of glycogen stores and possibly increased extrahepatic gluconeogenesis. Lipid metabolism was unaffected in fed LGsKO mice, but fasted LGsKO mice had increased lipogenic and reduced lipid oxidation gene expression in liver and increased serum triglyceride and FFA levels. LGsKO mice had very high serum glucagon and glucagon-like peptide–1 levels and pancreatic α cell hyperplasia, probably secondary to hepatic glucagon resistance and/or chronic hypoglycemia. Our results define novel roles for hepatic Gs-signaling pathways in glucose and lipid regulation, which may prove useful in designing new therapeutic targets for diabetes and obesity. PMID:16239968

  17. Impact of T1r3 and Trpm5 on Carbohydrate Preference and Acceptance in C57BL/6 Mice

    PubMed Central

    2013-01-01

    Knockout (KO) mice missing the sweet taste receptor subunit T1r3 or the signaling protein Trpm5 have greatly attenuated sweetener preferences but learn to prefer sucrose in 24-h tests. Here, we examined 24-h preferences of T1r3 KO, Trpm5 KO, and C57BL/6J wild-type (WT) mice for glucose, fructose, galactose, and corn starch. Unlike glucose, fructose has little postoral reward effect in WT mice, whereas conflicting data have been obtained with galactose. Naïve KO mice were initially indifferent to dilute glucose solutions (0.5–4%) but exhibited strong preferences for 8–32% concentrations. In a second test, they strongly preferred (~90%) all glucose concentrations although they drank less sugar than WT mice. Naïve KO mice were indifferent to 0.5–8% fructose and avoided 16–32% fructose. However, the glucose-experienced KO mice displayed significant preferences for all fructose solutions. Naïve KO mice preferred only 8% galactose, whereas WT mice preferred 4–16% galactose, and all mice avoided 32% galactose. Galactose experience enhanced the preference for this sugar in KO and WT mice. Naïve T1r3 KO and WT mice displayed similar preferences for 0.5–32% corn starch, which were enhanced by starch experience. Naïve Trpm5 KO mice did not prefer starch but did so after 1-bottle starch experience. The results confirm the sweet taste deficits of T1r3 KO and Trpm5 KO mice but demonstrate their ability to develop strong glucose and milder galactose preferences attributed to the postoral actions of these sugars. The acquired preference for the non-sweet flavor properties of glucose generalized to those of fructose. The findings further demonstrate that although Trpm5 (but not T1r3) signaling is essential for starch preference, Trpm5 KO mice can learn to prefer starch based on its postoral effects. PMID:23547138

  18. Infection with koala retrovirus subgroup B (KoRV-B), but not KoRV-A, is associated with chlamydial disease in free-ranging koalas (Phascolarctos cinereus).

    PubMed

    Waugh, Courtney A; Hanger, Jonathan; Loader, Joanne; King, Andrew; Hobbs, Matthew; Johnson, Rebecca; Timms, Peter

    2017-03-09

    The virulence of chlamydial infection in wild koalas is highly variable between individuals. Some koalas can be infected (PCR positive) with Chlamydia for long periods but remain asymptomatic, whereas others develop clinical disease. Chlamydia in the koala has traditionally been studied without regard to coinfection with other pathogens, although koalas are usually subject to infection with koala retrovirus (KoRV). Retroviruses can be immunosuppressive, and there is evidence of an immunosuppressive effect of KoRV in vitro. Originally thought to be a single endogenous strain, a new, potentially more virulent exogenous variant (KoRV-B) was recently reported. We hypothesized that KoRV-B might significantly alter chlamydial disease outcomes in koalas, presumably via immunosuppression. By studying sub-groups of Chlamydia and KoRV infected koalas in the wild, we found that neither total KoRV load (either viraemia or proviral copies per genome), nor chlamydial infection level or strain type, was significantly associated with chlamydial disease risk. However, PCR positivity with KoRV-B was significantly associated with chlamydial disease in koalas (p = 0.02961). This represents an example of a recently evolved virus variant that may be predisposing its host (the koala) to overt clinical disease when co-infected with an otherwise asymptomatic bacterial pathogen (Chlamydia).

  19. Fluoxetine Protection in Decompression Sickness in Mice is Enhanced by Blocking TREK-1 Potassium Channel with the "spadin" Antidepressant.

    PubMed

    Vallée, Nicolas; Lambrechts, Kate; De Maistre, Sébastien; Royal, Perrine; Mazella, Jean; Borsotto, Marc; Heurteaux, Catherine; Abraini, Jacques; Risso, Jean-Jacques; Blatteau, Jean-Eric

    2016-01-01

    In mice, disseminated coagulation, inflammation, and ischemia induce neurological damage that can lead to death. These symptoms result from circulating bubbles generated by a pathogenic decompression. Acute fluoxetine treatment or the presence of the TREK-1 potassium channel increases the survival rate when mice are subjected to an experimental dive/decompression protocol. This is a paradox because fluoxetine is a blocker of TREK-1 channels. First, we studied the effects of an acute dose of fluoxetine (50 mg/kg) in wild-type (WT) and TREK-1 deficient mice (knockout homozygous KO and heterozygous HET). Then, we combined the same fluoxetine treatment with a 5-day treatment protocol with spadin, in order to specifically block TREK-1 activity (KO-like mice). KO and KO-like mice were regarded as antidepressed models. In total, 167 mice (45 WTcont 46 WTflux 30 HETflux and 46 KOflux) constituting the flux-pool and 113 supplementary mice (27 KO-like 24 WTflux2 24 KO-likeflux 21 WTcont2 17 WTno dive) constituting the spad-pool were included in this study. Only 7% of KO-TREK-1 treated with fluoxetine (KOflux) and 4% of mice treated with both spadin and fluoxetine (KO-likeflux) died from decompression sickness (DCS) symptoms. These values are much lower than those of WT control (62%) or KO-like mice (41%). After the decompression protocol, mice showed significant consumption of their circulating platelets and leukocytes. Spadin antidepressed mice were more likely to exhibit DCS. Nevertheless, mice which had both blocked TREK-1 channels and fluoxetine treatment were better protected against DCS. We conclude that the protective effect of such an acute dose of fluoxetine is enhanced when TREK-1 is inhibited. We confirmed that antidepressed models may have worse DCS outcomes, but concomitant fluoxetine treatment not only decreased DCS severity but increased the survival rate.

  20. Lack of antiviral antibody response in koalas infected with koala retroviruses (KoRV).

    PubMed

    Fiebig, Uwe; Keller, Martina; Möller, Annekatrin; Timms, Peter; Denner, Joachim

    2015-02-16

    Many wild koalas are infected with the koala retrovirus, KoRV, some of which suffer from lymphoma and chlamydial disease. Three subgroups, KoRV-A, KoRV-B and KoRV-J, have so far been described. It is well known that other closely related gammaretroviruses can induce tumours and severe immunodeficiencies in their respective hosts and a possible role for KoRV infection in lymphoma and chlamydial disease in koalas has been suggested. In many wild koalas, KoRV-A has become endogenised, i.e., it is integrated in the germ-line and is passed on with normal cellular genes. In this study, sera from koalas in European zoos and from wild animals in Australia were screened for antibodies against KoRV-A. These naturally infected animals all carry endogenous KoRV-A and two zoo animals are also infected with KoRV-B. The antibody response is generally an important diagnostic tool for detecting retrovirus infections. However, when Western blot analyses were performed using purified virus or recombinant proteins corresponding to KoRV-A, none of the koalas tested positive for specific antibodies, suggesting a state of tolerance. These results have implications for koala vaccination, as they suggest that therapeutic immunisation of animals carrying and expressing endogenous KoRV-A will not be successful. However, it remains unclear whether these animals can be immunised against KoRV-B and immunisation of uninfected koalas could still be worthwhile. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Large-conductance Ca2+-activated K+ channel β1-subunit knockout mice are not hypertensive

    PubMed Central

    Garver, Hannah; Galligan, James J.; Fink, Gregory D.

    2011-01-01

    Large-conductance Ca2+-activated K+ (BK) channels are composed of pore-forming α-subunits and accessory β1-subunits that modulate Ca2+ sensitivity. BK channels regulate arterial myogenic tone and renal Na+ clearance/K+ reabsorption. Previous studies using indirect or short-term blood pressure measurements found that BK channel β1-subunit knockout (BK β1-KO) mice were hypertensive. We evaluated 24-h mean arterial pressure (MAP) and heart rate in BK β1-KO mice using radiotelemetry. BK β1-KO mice did not have a higher 24-h average MAP when compared with wild-type (WT) mice, although MAP was ∼10 mmHg higher at night. The dose-dependent peak declines in MAP by nifedipine were only slightly larger in BK β1-KO mice. In BK β1-KO mice, giving 1% NaCl to mice to drink for 7 days caused a transient (5 days) elevation of MAP (∼5 mmHg); MAP returned to pre-saline levels by day 6. BK β1-KO mesenteric arteries in vitro demonstrated diminished contractile responses to paxilline, increased reactivity to Bay K 8644 and norepinephrine (NE), and maintained relaxation to isoproterenol. Paxilline and Bay K 8644 did not constrict WT or BK β1-KO mesenteric veins (MV). BK β1-subunits are not expressed in MV. The results indicate that BK β1-KO mice are not hypertensive on normal or high-salt intake. BK channel deficiency increases arterial reactivity to NE and L-type Ca2+ channel function in vitro, but the L-type Ca2+ channel modulation of MAP is not altered in BK β1-KO mice. BK and L-type Ca2+ channels do not modulate murine venous tone. It appears that selective loss of BK channel function in arteries only is not sufficient to cause sustained hypertension. PMID:21131476

  2. Neuregulin 3 Knockout Mice Exhibit Behaviors Consistent with Psychotic Disorders

    PubMed Central

    Hayes, Lindsay N.; Shevelkin, Alexey; Zeledon, Mariela; Steel, Gary; Chen, Pei-Lung; Obie, Cassandra; Pulver, Ann; Avramopoulos, Dimitrios; Valle, David; Sawa, Akira; Pletnikov, Mikhail V.

    2016-01-01

    Neuregulin 3 (NRG3) is a paralog of NRG1. Genetic studies in schizophrenia demonstrate that risk variants in NRG3 are associated with cognitive and psychotic symptom severity, and several intronic single nucleotide polymorphisms in NRG3 are associated with delusions in patients with schizophrenia. In order to gain insights into the biological function of the gene, we generated a novel Nrg3 knockout (KO) mouse model and tested for neurobehavioral phenotypes relevant to psychotic disorders. KO mice displayed novelty-induced hyperactivity, impaired prepulse inhibition of the acoustic startle response, and deficient fear conditioning. No gross cytoarchitectonic or layer abnormalities were noted in the brain of KO mice. Our findings suggest that deletion of the Nrg3 gene leads to alterations consistent with aspects of schizophrenia. We propose that KO mice will provide a valuable animal model to determine the role of the NRG3 in the molecular pathogenesis of schizophrenia and other psychotic disorders. PMID:27606322

  3. Detection of koala retrovirus subgroup B (KoRV-B) in animals housed at European zoos.

    PubMed

    Fiebig, Uwe; Keller, Martina; Denner, Joachim

    2016-12-01

    Many koalas carry an endogenous retrovirus, KoRV-A, in their genome. Recently, a second retrovirus, KoRV-B, was detected in koalas in Japanese and U.S. zoos. However, this virus is not endogenous, differs in the receptor binding site of the surface envelope protein, and uses a receptor different from that of KoRV-A. We describe here a KoRV-B found in koalas at zoos in Germany and Belgium that differs slightly from that found in the Los Angeles zoo.

  4. CEP290 alleles in mice disrupt tissue-specific cilia biogenesis and recapitulate features of syndromic ciliopathies.

    PubMed

    Rachel, Rivka A; Yamamoto, Erin A; Dewanjee, Mrinal K; May-Simera, Helen L; Sergeev, Yuri V; Hackett, Alice N; Pohida, Katherine; Munasinghe, Jeeva; Gotoh, Norimoto; Wickstead, Bill; Fariss, Robert N; Dong, Lijin; Li, Tiansen; Swaroop, Anand

    2015-07-01

    Distinct mutations in the centrosomal-cilia protein CEP290 lead to diverse clinical findings in syndromic ciliopathies. We show that CEP290 localizes to the transition zone in ciliated cells, precisely to the region of Y-linkers between central microtubules and plasma membrane. To create models of CEP290-associated ciliopathy syndromes, we generated Cep290(ko/ko) and Cep290(gt/gt) mice that produce no or a truncated CEP290 protein, respectively. Cep290(ko/ko) mice exhibit early vision loss and die from hydrocephalus. Retinal photoreceptors in Cep290(ko/ko) mice lack connecting cilia, and ciliated ventricular ependyma fails to mature. The minority of Cep290(ko/ko) mice that escape hydrocephalus demonstrate progressive kidney pathology. Cep290(gt/gt) mice die at mid-gestation, and the occasional Cep290(gt/gt) mouse that survives shows hydrocephalus and severely cystic kidneys. Partial loss of CEP290-interacting ciliopathy protein MKKS mitigates lethality and renal pathology in Cep290(gt/gt) mice. Our studies demonstrate domain-specific functions of CEP290 and provide novel therapeutic paradigms for ciliopathies. Published by Oxford University Press 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  5. Ethanol consumption in mice lacking CD14, TLR2, TLR4, or MyD88

    PubMed Central

    Blednov, Yuri A.; Black, Mendy; Chernis, Julia; Da Costa, Adriana; Mayfield, Jody; Harris, R. Adron

    2016-01-01

    Background Molecular and behavioral studies support a role for innate immune proinflammatory pathways in mediating the effects of alcohol. Increased levels of Toll-like receptors (TLRs) have been observed in animal models of alcohol consumption and in human alcoholics, and many of these TLRs signal via the MyD88-dependent pathway. We hypothesized that this pathway is involved in alcohol drinking and examined some of its key signaling components. Methods Different ethanol drinking paradigms were studied in male and female control C57BL/6J mice vs. mice lacking CD14, TLR2, TLR4 (C57BL/10ScN), or MyD88. We studied continuous and intermittent access two-bottle choice (2BC) and one-bottle and 2BC drinking-in-the-dark (DID) tests as well as preference for saccharin, quinine, and NaCl. Results In the 2BC continuous access test, ethanol intake decreased in male TLR2 knockout (KO) mice, and we previously reported reduced 2BC drinking in male and female CD14 KO mice. In the intermittent access 2BC test, ethanol intake decreased in CD14 KO male and female mice, whereas drinking increased in MyD88 KO male mice. In the 2BC-DID test, ethanol drinking decreased in male and female mice lacking TLR2, whereas drinking increased in MyD88 KO male mice. In the one-bottle DID test, ethanol intake decreased in female TLR2 KO mice. TLR2 KO and CD14 KO mice did not differ in saccharin preference but showed reduced preference for NaCl. MyD88 KO mice showed a slight reduction in preference for saccharin. Conclusions Deletion of key components of the MyD88-dependent pathway produced differential effects on ethanol intake by decreasing (TLR2 KO and CD14 KO) or increasing (MyD88 KO) drinking, while deletion of TLR4 had no effect. Some of the drinking effects depended on the sex of the mice and/or the ethanol-drinking model. PMID:28146272

  6. Role of Olfaction in the Conditioned Sucrose Preference of Sweet-Ageusic T1R3 Knockout Mice

    PubMed Central

    Zukerman, Steven; Touzani, Khalid; Margolskee, Robert F.

    2009-01-01

    Prior work has shown that sweet taste–deficient T1R3 knockout (KO) mice developed significant sucrose preferences when given long-term sugar versus water tests. The current study investigated the role of olfaction in this experience-conditioned sucrose preference. T1R3 KO and C57BL/6 wild-type (WT) mice were given 24-h sugar versus water tests with ascending concentrations of sucrose (0.5–32%), after which the mice received olfactory bulbectomy (OBx) or sham surgery. When retested with sucrose, the Sham-KO mice preferred all sugar solutions to water, although their intake and preference were less than those of the Sham-WT mice. The OBx-KO mice, in contrast, showed no or weak preferences for dilute sucrose solutions (0.5–8%) although they strongly preferred concentrated sugar solutions (16–32%). OBx-WT mice displayed only a partial reduction in their sucrose preference. Although the OBx mice of both genotypes underconsumed dilute sucrose solutions relative to Sham mice, they overconsumed concentrated sucrose. These results indicate that olfaction plays a critical role in the conditioned preference of T1R3 KO mice for dilute sugar solutions. Further, the fact that OBx-KO mice preferred concentrated sucrose solutions in the absence of normal sweet taste and olfactory sensations underscores the potency of postoral nutritive signals in promoting ingestion. PMID:19736224

  7. CD34 EXPRESSION BY HAIR FOLLICLE STEM CELLS IS REQUIRED FOR SKIN TUMOR DEVELOPMENT IN MICE

    EPA Science Inventory

    We used knockout mice to show that a cell surface protein called CD34 is required for skin tumor formation in mice. Wild type mice treated with 7-12-Dimethylbenz(a)anthracene (DMBA) and a tumor promoter developed papillomas. When we treated CD34 knockout (KO) mice the same way, n...

  8. Intravitreal delivery of AAV8 retinoschisin results in cell type-specific gene expression and retinal rescue in the Rs1-KO mouse

    PubMed Central

    Park, TK; Wu, Z; Kjellstrom, S; Zeng, Y; Bush, RA; Sieving, PA; Colosi, P

    2009-01-01

    X-linked juvenile retinoschisis (XLRS) is a neurodevelopmental abnormality caused by retinoschisin gene mutations. XLRS is characterized by splitting through the retinal layers and impaired synaptic transmission of visual signals resulting in impaired acuity and a propensity to retinal detachment. Several groups have treated murine retinoschisis models successfully using adeno-associated virus (AAV) vectors. Owing to the fragile nature of XLRS retina, translating this therapy to the clinic may require an alternative to invasive subretinal vector administration. Here we show that all layers of the retinoschisin knockout (Rs1-KO) mouse retina can be transduced efficiently with AAV vectors administered by simple vitreous injection. Retinoschisin expression was restricted to the neuroretina using a new vector that uses a 3.5-kb human retinoschisin promoter and an AAV type 8 capsid. Intravitreal administration to Rs1-KO mice resulted in robust retinoschisin expression with a retinal distribution similar to that observed in wild-type retina, including the expression by the photoreceptors lying deep in the retina. No off-target expression was observed. Rs1-KO mice treated with this vector showed a decrease in the schisis cavities and had improved retinal signaling evaluated by recording the electroretinogram 11–15 weeks after the application. PMID:19458650

  9. Fat-specific Dicer deficiency accelerates aging and mitigates several effects of dietary restriction in mice.

    PubMed

    Reis, Felipe C G; Branquinho, Jéssica L O; Brandão, Bruna B; Guerra, Beatriz A; Silva, Ismael D; Frontini, Andrea; Thomou, Thomas; Sartini, Loris; Cinti, Saverio; Kahn, C Ronald; Festuccia, William T; Kowaltowski, Alicia J; Mori, Marcelo A

    2016-06-01

    Aging increases the risk of type 2 diabetes, and this can be prevented by dietary restriction (DR). We have previously shown that DR inhibits the downregulation of miRNAs and their processing enzymes - mainly Dicer - that occurs with aging in mouse white adipose tissue (WAT). Here we used fat-specific Dicer knockout mice (AdicerKO) to understand the contributions of adipose tissue Dicer to the metabolic effects of aging and DR. Metabolomic data uncovered a clear distinction between the serum metabolite profiles of Lox control and AdicerKO mice, with a notable elevation of branched-chain amino acids (BCAA) in AdicerKO. These profiles were associated with reduced oxidative metabolism and increased lactate in WAT of AdicerKO mice and were accompanied by structural and functional changes in mitochondria, particularly under DR. AdicerKO mice displayed increased mTORC1 activation in WAT and skeletal muscle, where Dicer expression is not affected. This was accompanied by accelerated age-associated insulin resistance and premature mortality. Moreover, DR-induced insulin sensitivity was abrogated in AdicerKO mice. This was reverted by rapamycin injection, demonstrating that insulin resistance in AdicerKO mice is caused by mTORC1 hyperactivation. Our study evidences a DR-modulated role for WAT Dicer in controlling metabolism and insulin resistance.

  10. Key Glycolytic Enzyme Activities of Skeletal Muscle Are Decreased under Fed and Fasted States in Mice with Knocked Down Levels of Shc Proteins

    PubMed Central

    Hagopian, Kevork; Tomilov, Alexey A.; Kim, Kyoungmi; Cortopassi, Gino A.; Ramsey, Jon J.

    2015-01-01

    Shc proteins interact with the insulin receptor, indicating a role in regulating glycolysis. To investigate this idea, the activities of key glycolytic regulatory enzymes and metabolites levels were measured in skeletal muscle from mice with low levels of Shc proteins (ShcKO) and wild-type (WT) controls. The activities of hexokinase, phosphofructokinase-1 and pyruvate kinase were decreased in ShcKO versus WT mice under both fed and fasted conditions. Increased alanine transaminase and branched-chain amino acid transaminase activities were also observed in ShcKO mice under both fed and fasting conditions. Protein expression of glycolytic enzymes was unchanged in the ShcKO and WT mice, indicating that decreased activities were not due to changes in their transcription. Changes in metabolite levels were consistent with the observed changes in enzyme activities. In particular, the levels of fructose-2,6-bisphosphate, a potent activator of phosphofructokinase-1, were consistently decreased in the ShcKO mice. Furthermore, the levels of lactate (inhibitor of hexokinase and phosphofructokinase-1) and citrate (inhibitor of phosphofructokinase-1 and pyruvate kinase) were increased in fed and fasted ShcKO versus WT mice. Pyruvate dehydrogenase activity was lower in ShcKO versus WT mice under fed conditions, and showed inhibition under fasting conditions in both ShcKO and WT mice, with ShcKO mice showing less inhibition than the WT mice. Pyruvate dehydrogenase kinase 4 levels were unchanged under fed conditions but were lower in the ShcKO mice under fasting conditions. These studies indicate that decreased levels of Shc proteins in skeletal muscle lead to a decreased glycolytic capacity in both fed and fasted states. PMID:25880638

  11. Impaired Discrimination Learning in Mice Lacking the NMDA Receptor NR2A Subunit

    ERIC Educational Resources Information Center

    Brigman, Jonathan L.; Feyder, Michael; Saksida, Lisa M.; Bussey, Timothy J.; Mishina, Masayoshi; Holmes, Andrew

    2008-01-01

    N-Methyl-D-aspartate receptors (NMDARs) mediate certain forms of synaptic plasticity and learning. We used a touchscreen system to assess NR2A subunit knockout mice (KO) for (1) pairwise visual discrimination and reversal learning and (2) acquisition and extinction of an instrumental response requiring no pairwise discrimination. NR2A KO mice…

  12. CALHM1 Deletion in Mice Affects Glossopharyngeal Taste Responses, Food Intake, Body Weight, and Life Span

    PubMed Central

    Schmolling, Jared; Marambaud, Philippe; Rose-Hellekant, Teresa A.

    2015-01-01

    Stimulation of Type II taste receptor cells (TRCs) with T1R taste receptors causes sweet or umami taste, whereas T2Rs elicit bitter taste. Type II TRCs contain the calcium channel, calcium homeostasis modulator protein 1 (CALHM1), which releases adenosine triphosphate (ATP) transmitter to taste fibers. We have previously demonstrated with chorda tympani nerve recordings and two-bottle preference (TBP) tests that mice with genetically deleted Calhm1 (knockout [KO]) have severely impaired perception of sweet, bitter, and umami compounds, whereas their sour and salty tasting ability is unaltered. Here, we present data from KO mice of effects on glossopharyngeal (NG) nerve responses, TBP, food intake, body weight, and life span. KO mice have no NG response to sweet and a suppressed response to bitter compared with control (wild-type [WT]) mice. KO mice showed some NG response to umami, suggesting that umami taste involves both CALHM1- and non-CALHM1-modulated signals. NG responses to sour and salty were not significantly different between KO and WT mice. Behavioral data conformed in general with the NG data. Adult KO mice consumed less food, weighed significantly less, and lived almost a year longer than WT mice. Taken together, these data demonstrate that sweet taste majorly influences food intake, body weight, and life span. PMID:25855639

  13. Osteopontin Deficiency Accelerates Spontaneous Colitis in Mice with Disrupted Gut Microbiota and Macrophage Phagocytic Activity

    PubMed Central

    Toyonaga, Takahiko; Nakase, Hiroshi; Ueno, Satoru; Matsuura, Minoru; Yoshino, Takuya; Honzawa, Yusuke; Itou, Ayako; Namba, Kazuyoshi; Minami, Naoki; Yamada, Satoshi; Koshikawa, Yorimitsu; Uede, Toshimitsu; Chiba, Tsutomu; Okazaki, Kazuichi

    2015-01-01

    Background Osteopontin (OPN) is a multifunctional protein expressed in a variety of tissues and cells. Recent studies revealed increased OPN expression in the inflamed intestinal tissues of patients with inflammatory bowel disease (IBD). The role of OPN in the pathophysiology of IBD, however, remains unclear. Aims To investigate the role of OPN in the development of intestinal inflammation using a murine model of IBD, interleukin-10 knock out (IL-10 KO) mice. Methods We compared the development of colitis between IL-10 KO and OPN/IL-10 double KO (DKO) mice. OPN expression in the colonic tissues of IL-10 KO mice was examined by fluorescence in situ hybridization (FISH) analysis. Enteric microbiota were compared between IL-10 KO and OPN/IL-10 DKO mice by terminal restriction fragment length polymorphism analysis. The effect of OPN on macrophage phagocytic function was evaluated by phagocytosis assay. Results OPN/IL-10 DKO mice had an accelerated onset of colitis compared to IL-10 KO mice. FISH analysis revealed enhanced OPN synthesis in the colonic epithelial cells of IL-10 KO mice. OPN/IL-10 DKO mice had a distinctly different enteric bacterial profile with a significantly lower abundance of Clostridium subcluster XIVa and a greater abundance of Clostridium cluster XVIII compared to IL-10 KO mice. Intracellular OPN deletion in macrophages impaired phagocytosis of fluorescence particle-conjugated Escherichia coli in vitro. Exogenous OPN enhanced phagocytosis by OPN-deleted macrophages when administered at doses of 1 to 100 ng/ml, but not 1000 ng/ml. Conclusions OPN deficiency accelerated the spontaneous development of colitis in mice with disrupted gut microbiota and macrophage phagocytic activity. PMID:26274807

  14. A Conditioned Aversion Study of Sucrose and SC45647 Taste in TRPM5 Knockout Mice

    PubMed Central

    Eddy, Meghan C.; Eschle, Benjamin K.; Peterson, Darlene; Lauras, Nathan; Margolskee, Robert F.

    2012-01-01

    Previously, published studies have reported mixed results regarding the role of the TRPM5 cation channel in signaling sweet taste by taste sensory cells. Some studies have reported a complete loss of sweet taste preference in TRPM5 knockout (KO) mice, whereas others have reported only a partial loss of sweet taste preference. This study reports the results of conditioned aversion studies designed to motivate wild-type (WT) and KO mice to respond to sweet substances. In conditioned taste aversion experiments, WT mice showed nearly complete LiCl-induced response suppression to sucrose and SC45647. In contrast, TRPM5 KO mice showed a much smaller conditioned aversion to either sweet substance, suggesting a compromised, but not absent, ability to detect sweet taste. A subsequent conditioned flavor aversion experiment was conducted to determine if TRPM5 KO mice were impaired in their ability to learn a conditioned aversion. In this experiment, KO and WT mice were conditioned to a mixture of SC45647 and amyl acetate (an odor cue). Although WT mice avoided both components of the stimulus mixture, they avoided SC45647 more than the odor cue. The KO mice also avoided both stimuli, but they avoided the odor component more than SC45647, suggesting that while the KO mice are capable of learning an aversion, to them the odor cue was more salient than the taste cue. Collectively, these findings suggest the TRPM5 KO mice have some residual ability to detect SC45647 and sucrose, and, like bitter, there may be a TRPM5-independent transduction pathway for detecting these substances. PMID:21987728

  15. A conditioned aversion study of sucrose and SC45647 taste in TRPM5 knockout mice.

    PubMed

    Eddy, Meghan C; Eschle, Benjamin K; Peterson, Darlene; Lauras, Nathan; Margolskee, Robert F; Delay, Eugene R

    2012-06-01

    Previously, published studies have reported mixed results regarding the role of the TRPM5 cation channel in signaling sweet taste by taste sensory cells. Some studies have reported a complete loss of sweet taste preference in TRPM5 knockout (KO) mice, whereas others have reported only a partial loss of sweet taste preference. This study reports the results of conditioned aversion studies designed to motivate wild-type (WT) and KO mice to respond to sweet substances. In conditioned taste aversion experiments, WT mice showed nearly complete LiCl-induced response suppression to sucrose and SC45647. In contrast, TRPM5 KO mice showed a much smaller conditioned aversion to either sweet substance, suggesting a compromised, but not absent, ability to detect sweet taste. A subsequent conditioned flavor aversion experiment was conducted to determine if TRPM5 KO mice were impaired in their ability to learn a conditioned aversion. In this experiment, KO and WT mice were conditioned to a mixture of SC45647 and amyl acetate (an odor cue). Although WT mice avoided both components of the stimulus mixture, they avoided SC45647 more than the odor cue. The KO mice also avoided both stimuli, but they avoided the odor component more than SC45647, suggesting that while the KO mice are capable of learning an aversion, to them the odor cue was more salient than the taste cue. Collectively, these findings suggest the TRPM5 KO mice have some residual ability to detect SC45647 and sucrose, and, like bitter, there may be a TRPM5-independent transduction pathway for detecting these substances.

  16. Effects of gender on locomotor sensitivity to amphetamine, body weight, and fat mass in regulator of G protein signaling 9 (RGS9) knockout mice.

    PubMed

    Walker, Paul D; Jarosz, Patricia A; Bouhamdan, Mohamad; MacKenzie, Robert G

    2015-01-01

    Regulator of G-protein signaling (RGS) protein 9-2 is enriched in the striatum where it modulates dopamine and opioid receptor-mediated signaling. RGS9 knockout (KO) mice show increased psychostimulant-induced behavioral sensitization, as well as exhibit higher body weights and greater fat accumulation compared to wild-type (WT) littermates. In the present study, we found gender influences on each of these phenotypic characteristics. Female RGS9 KO mice exhibited greater locomotor sensitization to amphetamine (1.0mg/kg) treatment as compared to male RGS9 KO mice. Male RGS9 KO mice showed increased body weights as compared to male WT littermates, while no such differences were detected in female mice. Quantitative magnetic resonance showed that male RGS9 KO mice accumulated greater fat mass vs. WT littermates at 5months of age. Such observations could not be explained by increased caloric consumption since male and female RGS9 KO mice demonstrated equivalent daily food intake as compared to their respective WT littermates. Although indirect calorimetry methods found decreased oxygen consumption and carbon dioxide production during the 12-hour dark phase in male RGS9 KO vs. WT mice which are indicative of less energy expenditure, male RGS9 KO mice exhibited lower levels of locomotor activity during this period. Genotype had no effect on metabolic activities when KO and WT groups were compared under fasting vs. feeding treatments. In summary, these results highlight the importance of factoring gender into the experimental design since many studies conducted in RGS9 KO mice utilize locomotor activity as a measured outcome. Copyright © 2014. Published by Elsevier Inc.

  17. Supra-subduction zone magmatism of the Koçali ophiolite, SE Turkey

    NASA Astrophysics Data System (ADS)

    Beyarslan, Melahat

    2017-05-01

    The Late Cretaceous Koçali ophiolite is an important element within the southeastern Anatolian ophiolite belt and contains all components of a complete ophiolite, including mantle peridotites (harzburgites, and subordinate dunite) gabbros, sheeted dyke complexes, lower volcanic unit (pillowed basalts), and upper volcanic unit (andesite and andesitic pyroclastics) plagiogranite and ultramafic rocks intruded into the gabbros. All components of the Koçali ophiolites show strong suprasubduction-zone affinities, from harzburgitic mantle to basaltic lavas. The radiolarian faunas and geochronological data indicate that there are two different volcanic units: Tarasa volcanics and volcanics of the Koçali ophiolite. While the Tarasa volcanics are of Carnian to Rhaetian age, the Koçali ophiolite is of the Late Cretaceous age. The geochemical features indicate an E-MORB source for the Tarasa volcanics, and a forearc source for the Koçali ophiolite.

  18. Increased anxiety-related behaviour in Hint1 knockout mice.

    PubMed

    Varadarajulu, Jeeva; Lebar, Maria; Krishnamoorthy, Gurumoorthy; Habelt, Sonja; Lu, Jia; Bernard Weinstein, I; Li, Haiyang; Holsboer, Florian; Turck, Christoph W; Touma, Chadi

    2011-07-07

    Several reports have implicated a role for the histidine triad nucleotide-binding protein-1 (Hint1) in psychiatric disorders. We have studied the emotional behaviour of male Hint1 knockout (Hint1 KO) mice in a battery of tests and performed biochemical analyses on brain tissue. The behavioural analysis revealed that Hint1 KO mice exhibit an increased emotionality phenotype compared to wildtype (WT) mice, while no significant differences in locomotion or general exploratory activity were noted. In the elevated plus-maze (EPM) test, the Hint1 KO animals entered the open arms of the apparatus less often than WT littermates. Similarly, in the dark-light box test, Hint1 KO mice spent less time in the lit compartment and the number of entries were reduced, which further confirmed an increased anxiety-related behaviour. Moreover, the Hint1 KO animals showed significantly more struggling and less floating behaviour in the forced swim test (FST), indicating an increased emotional arousal in aversive situations. Hint1 is known as a protein kinase C (PKC) interacting protein. Western blot analysis showed that PKCγ expression was elevated in Hint1 KO compared to WT mice. Interestingly, PKCγ mRNA levels of the two groups did not show a significant difference, implying a post-transcriptional PKCγ regulation. In addition, PKC enzymatic activity was increased in Hint1 KO compared to WT mice. In summary, our results indicate a role for Hint1 and PKCγ in modulating anxiety-related and stress-coping behaviour in mice. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Distinct motor impairments of dopamine D1 and D2 receptor knockout mice revealed by three types of motor behavior

    PubMed Central

    Nakamura, Toru; Sato, Asako; Kitsukawa, Takashi; Momiyama, Toshihiko; Yamamori, Tetsuo; Sasaoka, Toshikuni

    2014-01-01

    Both D1R and D2R knock out (KO) mice of the major dopamine receptors show significant motor impairments. However, there are some discrepant reports, which may be due to the differences in genetic background and experimental procedures. In addition, only few studies directly compared the motor performance of D1R and D2R KO mice. In this paper, we examined the behavioral difference among N10 congenic D1R and D2R KO, and wild type (WT) mice. First, we examined spontaneous motor activity in the home cage environment for consecutive 5 days. Second, we examined motor performance using the rota-rod task, a standard motor task in rodents. Third, we examined motor ability with the Step-Wheel task in which mice were trained to run in a motor-driven turning wheel adjusting their steps on foothold pegs to drink water. The results showed clear differences among the mice of three genotypes in three different types of behavior. In monitoring spontaneous motor activities, D1R and D2R KO mice showed higher and lower 24 h activities, respectively, than WT mice. In the rota-rod tasks, at a low speed, D1R KO mice showed poor performance but later improved, whereas D2R KO mice showed a good performance at early days without further improvement. When first subjected to a high speed task, the D2R KO mice showed poorer rota-rod performance at a low speed than the D1R KO mice. In the Step-Wheel task, across daily sessions, D2R KO mice increased the duration that mice run sufficiently close to the spout to drink water, and decreased time to touch the floor due to missing the peg steps and number of times the wheel was stopped, which performance was much better than that of D1R KO mice. These incongruent results between the two tasks for D1R and D2R KO mice may be due to the differences in the motivation for the rota-rod and Step-Wheel tasks, aversion- and reward-driven, respectively. The Step-Wheel system may become a useful tool for assessing the motor ability of WT and mutant mice. PMID

  20. The skeletal structure of insulin-like growth factor I-deficient mice

    NASA Technical Reports Server (NTRS)

    Bikle, D.; Majumdar, S.; Laib, A.; Powell-Braxton, L.; Rosen, C.; Beamer, W.; Nauman, E.; Leary, C.; Halloran, B.

    2001-01-01

    The importance of insulin-like growth factor I (IGF-I) for growth is well established. However, the lack of IGF-I on the skeleton has not been examined thoroughly. Therefore, we analyzed the structural properties of bone from mice rendered IGF-I deficient by homologous recombination (knockout [k/o]) using histomorphometry, peripheral quantitative computerized tomography (pQCT), and microcomputerized tomography (muCT). The k/o mice were 24% the size of their wild-type littermates at the time of study (4 months). The k/o tibias were 28% and L1 vertebrae were 26% the size of wild-type bones. Bone formation rates (BFR) of k/o tibias were 27% that of the wild-type littermates. The k/o bones responded normally to growth hormone (GH; 1.7-fold increase) and supranormally to IGF-I (5.2-fold increase) with respect to BFR. Cortical thickness of the proximal tibia was reduced 17% in the k/o mouse. However, trabecular bone volume (bone volume/total volume [BV/TV]) was increased 23% (male mice) and 88% (female mice) in the k/o mice compared with wild-type controls as a result of increased connectivity, increased number, and decreased spacing of the trabeculae. These changes were either less or not found in L1. Thus, lack of IGF-I leads to the development of a bone structure, which, although smaller, appears more compact.

  1. Reduced inflammatory threshold indicates skin barrier defect in transglutaminase 3 knockout mice.

    PubMed

    Bognar, Peter; Nemeth, Ilona; Mayer, Balazs; Haluszka, Dora; Wikonkal, Norbert; Ostorhazi, Eszter; John, Susan; Paulsson, Mats; Smyth, Neil; Pasztoi, Maria; Buzas, Edit I; Szipocs, Robert; Kolonics, Attila; Temesvari, Erzsebet; Karpati, Sarolta

    2014-01-01

    Recently, a transglutaminase 3 knockout (TGM3/KO) mouse was generated that showed impaired hair development, but no gross defects in the epidermal barrier, although increased fragility of isolated corneocytes was demonstrated. Here we investigated the functionality of skin barrier in vivo by percutaneous sensitization to FITC in TGM3/KO (n=64) and C57BL/6 wild-type (WT) mice (n=36). Cutaneous inflammation was evaluated by mouse ear swelling test (MEST), histology, serum IgE levels, and by flow cytometry from draining lymph nodes. Inflammation-induced significant MEST difference (P<0.0001) was detected between KO and WT mice and was supported also by histopathology. A significant increase of CD4+ CD25+-activated T cells (P<0.01) and elevated serum IgE levels (P<0.05) in KO mice indicated more the development of FITC sensitization than an irritative reaction. Propionibacter acnes-induced intracutaneous inflammation showed no difference (P=0.2254) between the reactivity of WT and KO immune system. As in vivo tracer, FITC penetration from skin surface followed by two-photon microscopy demonstrated a more invasive percutaneous penetration in KO mice. The clinically uninvolved skin in TGM3/KO mice showed impaired barrier function and higher susceptibility to FITC sensitization indicating that TGM3 has a significant contribution to the functionally intact cutaneous barrier.

  2. Impaired functional organization in the visual cortex of muscarinic receptor knock-out mice.

    PubMed

    Groleau, Marianne; Nguyen, Hoang Nam; Vanni, Matthieu P; Huppé-Gourgues, Frédéric; Casanova, Christian; Vaucher, Elvire

    2014-09-01

    Acetylcholine modulates maturation and neuronal activity through muscarinic and nicotinic receptors in the primary visual cortex. However, the specific contribution of different muscarinic receptor subtypes in these neuromodulatory mechanisms is not fully understood. The present study evaluates in vivo the functional organization and the properties of the visual cortex of different groups of muscarinic receptor knock-out (KO) mice. Optical imaging of intrinsic signals coupled to continuous and episodic visual stimulation paradigms was used. Retinotopic maps along elevation and azimuth were preserved among the different groups of mice. However, compared to their wild-type counterparts, the apparent visual field along elevation was larger in M2/M4-KO mice but smaller in M1-KO. There was a reduction in the estimated relative receptive field size of V1 neurons in M1/M3-KO and M1-KO mice. Spatial frequency and contrast selectivity of V1 neuronal populations were affected only in M1/M3-KO and M1-KO mice. Finally, the neuronal connectivity was altered by the absence of M2/M4 muscarinic receptors. All these effects suggest the distinct roles of different subtypes of muscarinic receptors in the intrinsic organization of V1 and a strong involvement of the muscarinic transmission in the detectability of visual stimuli. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Fluoxetine Protection in Decompression Sickness in Mice is Enhanced by Blocking TREK-1 Potassium Channel with the “spadin” Antidepressant

    PubMed Central

    Vallée, Nicolas; Lambrechts, Kate; De Maistre, Sébastien; Royal, Perrine; Mazella, Jean; Borsotto, Marc; Heurteaux, Catherine; Abraini, Jacques; Risso, Jean-Jacques; Blatteau, Jean-Eric

    2016-01-01

    In mice, disseminated coagulation, inflammation, and ischemia induce neurological damage that can lead to death. These symptoms result from circulating bubbles generated by a pathogenic decompression. Acute fluoxetine treatment or the presence of the TREK-1 potassium channel increases the survival rate when mice are subjected to an experimental dive/decompression protocol. This is a paradox because fluoxetine is a blocker of TREK-1 channels. First, we studied the effects of an acute dose of fluoxetine (50 mg/kg) in wild-type (WT) and TREK-1 deficient mice (knockout homozygous KO and heterozygous HET). Then, we combined the same fluoxetine treatment with a 5-day treatment protocol with spadin, in order to specifically block TREK-1 activity (KO-like mice). KO and KO-like mice were regarded as antidepressed models. In total, 167 mice (45 WTcont 46 WTflux 30 HETflux and 46 KOflux) constituting the flux-pool and 113 supplementary mice (27 KO-like 24 WTflux2 24 KO-likeflux 21 WTcont2 17 WTno dive) constituting the spad-pool were included in this study. Only 7% of KO-TREK-1 treated with fluoxetine (KOflux) and 4% of mice treated with both spadin and fluoxetine (KO-likeflux) died from decompression sickness (DCS) symptoms. These values are much lower than those of WT control (62%) or KO-like mice (41%). After the decompression protocol, mice showed significant consumption of their circulating platelets and leukocytes. Spadin antidepressed mice were more likely to exhibit DCS. Nevertheless, mice which had both blocked TREK-1 channels and fluoxetine treatment were better protected against DCS. We conclude that the protective effect of such an acute dose of fluoxetine is enhanced when TREK-1 is inhibited. We confirmed that antidepressed models may have worse DCS outcomes, but concomitant fluoxetine treatment not only decreased DCS severity but increased the survival rate. PMID:26909044

  4. Narcolepsy susceptibility gene CCR3 modulates sleep-wake patterns in mice.

    PubMed

    Toyoda, Hiromi; Honda, Yoshiko; Tanaka, Susumu; Miyagawa, Taku; Honda, Makoto; Honda, Kazuki; Tokunaga, Katsushi; Kodama, Tohru

    2017-01-01

    Narcolepsy is caused by the loss of hypocretin (Hcrt) neurons and is associated with multiple genetic and environmental factors. Although abnormalities in immunity are suggested to be involved in the etiology of narcolepsy, no decisive mechanism has been established. We previously reported chemokine (C-C motif) receptor 3 (CCR3) as a novel susceptibility gene for narcolepsy. To understand the role of CCR3 in the development of narcolepsy, we investigated sleep-wake patterns of Ccr3 knockout (KO) mice. Ccr3 KO mice exhibited fragmented sleep patterns in the light phase, whereas the overall sleep structure in the dark phase did not differ between Ccr3 KO mice and wild-type (WT) littermates. Intraperitoneal injection of lipopolysaccharide (LPS) promoted wakefulness and suppressed both REM and NREM sleep in the light phase in both Ccr3 KO and WT mice. Conversely, LPS suppressed wakefulness and promoted NREM sleep in the dark phase in both genotypes. After LPS administration, the proportion of time spent in wakefulness was higher, and the proportion of time spent in NREM sleep was lower in Ccr3 KO compared to WT mice only in the light phase. LPS-induced changes in sleep patterns were larger in Ccr3 KO compared to WT mice. Furthermore, we quantified the number of Hcrt neurons and found that Ccr3 KO mice had fewer Hcrt neurons in the lateral hypothalamus compared to WT mice. We found abnormalities in sleep patterns in the resting phase and in the number of Hcrt neurons in Ccr3 KO mice. These observations suggest a role for CCR3 in sleep-wake regulation in narcolepsy patients.

  5. Prostaglandin-Endoperoxide Synthase 1 Mediates the Timing of Parturition in Mice Despite Unhindered Uterine Contractility.

    PubMed

    Herington, Jennifer L; O'Brien, Christine; Robuck, Michael F; Lei, Wei; Brown, Naoko; Slaughter, James C; Paria, Bibhash C; Mahadevan-Jansen, Anita; Reese, Jeff

    2018-01-01

    Cyclooxygenase (COX)-derived prostaglandins stimulate uterine contractions and prepare the cervix for parturition. Prior reports suggest Cox-1 knockout (KO) mice exhibit delayed parturition due to impaired luteolysis, yet the mechanism for late-onset delivery remains unclear. Here, we examined key factors for normal onset of parturition to determine whether any could account for the delayed parturition phenotype. Pregnant Cox-1KO mice did not display altered timing of embryo implantation or postimplantation growth. Although messenger RNAs of contraction-associated proteins (CAPs) were differentially expressed between Cox-1KO and wild-type (WT) myometrium, there were no differences in CAP agonist-induced intracellular calcium release, spontaneous or oxytocin (OT)-induced ex vivo uterine contractility, or in vivo uterine contractile pressure. Delayed parturition in Cox-1KO mice persisted despite exogenous OT treatment. Progesterone (P4) withdrawal, by ovariectomy or administration of the P4-antagonist RU486, diminished the delayed parturition phenotype of Cox-1KO mice. Because antepartum P4 levels do not decline in Cox-1KO females, P4-treated WT mice were examined for the effect of this hormone on in vivo uterine contractility and ex vivo cervical dilation. P4-treated WT mice had delayed parturition but normal uterine contractility. Cervical distensibility was decreased in Cox-1KO mice on the day of expected delivery and reduced in WT mice with long-term P4 treatment. Collectively, these findings show that delayed parturition in Cox-1KO mice is the result of impaired luteolysis and cervical dilation, despite the presence of strong uterine contractions. Copyright © 2018 Endocrine Society.

  6. Comprehensive behavioral analysis of pituitary adenylate cyclase-activating polypeptide (PACAP) knockout mice

    PubMed Central

    Hattori, Satoko; Takao, Keizo; Tanda, Koichi; Toyama, Keiko; Shintani, Norihito; Baba, Akemichi; Hashimoto, Hitoshi; Miyakawa, Tsuyoshi

    2012-01-01

    Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide acting as a neurotransmitter, neuromodulator, or neurotrophic factor. PACAP is widely expressed throughout the brain and exerts its functions through the PACAP-specific receptor (PAC1). Recent studies reveal that genetic variants of the PACAP and PAC1 genes are associated with mental disorders, and several behavioral abnormalities of PACAP knockout (KO) mice are reported. However, an insufficient number of backcrosses was made using PACAP KO mice on the C57BL/6J background due to their postnatal mortality. To elucidate the effects of PACAP on neuropsychiatric function, the PACAP gene was knocked out in F1 hybrid mice (C57BL/6J × 129SvEv) for appropriate control of the genetic background. The PACAP KO mice were then subjected to a behavioral test battery. PACAP deficiency had no significant effects on neurological screen. As shown previously, the mice exhibited significantly increased locomotor activity in a novel environment and abnormal anxiety-like behavior, while no obvious differences between genotypes were shown in home cage (HC) activity. In contrast to previous reports, the PACAP KO mice showed normal prepulse inhibition (PPI) and slightly decreased depression-like behavior. Previous study demonstrates that the social interaction (SI) in a resident-intruder test was decreased in PACAP KO mice. On the other hand, we showed that PACAP KO mice exhibited increased SI in Crawley's three-chamber social approach test, although PACAP KO had no significant impact on SI in a HC. PACAP KO mice also exhibited mild performance deficit in working memory in an eight-arm radial maze (RM) and the T-maze (TM), while they did not show any significant abnormalities in the left-right discrimination task in the TM. These results suggest that PACAP has an important role in the regulation of locomotor activity, social behavior, anxiety-like behavior and, potentially, working memory. PMID:23060763

  7. The effects of fish oil consumption on cardiovascular remodeling in ApoE deficient mice.

    PubMed

    Cleverley, Kelby; Du, Xiaozhou; Premecz, Sheena; Le, Khuong; Zeglinski, Matthew; Nicholson, Tiffany; Goh, Chun Y; Lu, Yan; Anderson, Hope D; Moghadasian, Mohammed H; Jassal, Davinder S

    2013-11-01

    Owing to their spontaneous development of atherosclerosis, apolipoprotein E knockout mice (ApoE(KO)) are one of the best studied animal models for this disease. Little is known about the utility of various omega-3 fatty acid regimens, in particular fish oils, in preventing cardiac disease in ApoE(KO) mice. The purpose of this study was to determine the cardiovascular effects of omega-3 fatty acid supplementation with either safflower oil (control), fish oil, flaxseed oil, or designed oil in ApoE(KO) mice fed a high-fat diet for a total of 16 weeks. In-vivo cardiac function was assessed weekly using murine echocardiography. Blood pressure, plasma lipid levels, and brain natriuretic peptide (BNP) were serially measured. The results show that ApoE(KO) mice fed fish oil demonstrated an increase in left ventricular wall thickness as a result of increased afterload. Despite chronic treatment with fish oil over 16 weeks, blood pressure increased in ApoE(KO) mice by 20% compared with the baseline. Both echocardiographic evidence of left ventricular hypertrophy and biochemical increase in BNP levels confirmed diastolic dysfunction in ApoE(KO) mice fed fish oil. This suggests that high-fat diet supplemented with fish oil may lead to adverse cardiovascular effects in ApoE deficient mice.

  8. ChREBP-Knockout Mice Show Sucrose Intolerance and Fructose Malabsorption.

    PubMed

    Kato, Takehiro; Iizuka, Katsumi; Takao, Ken; Horikawa, Yukio; Kitamura, Tadahiro; Takeda, Jun

    2018-03-12

    We have previously reported that 60% sucrose diet-fed ChREBP knockout mice (KO) showed body weight loss resulting in lethality. We aimed to elucidate whether sucrose and fructose metabolism are impaired in KO. Wild-type mice (WT) and KO were fed a diet containing 30% sucrose with/without 0.08% miglitol, an α-glucosidase inhibitor, and these effects on phenotypes were tested. Furthermore, we compared metabolic changes of oral and peritoneal fructose injection. A thirty percent sucrose diet feeding did not affect phenotypes in KO. However, miglitol induced lethality in 30% sucrose-fed KO. Thirty percent sucrose plus miglitol diet-fed KO showed increased cecal contents, increased fecal lactate contents, increased growth of lactobacillales and Bifidobacterium and decreased growth of clostridium cluster XIVa. ChREBP gene deletion suppressed the mRNA levels of sucrose and fructose related genes. Next, oral fructose injection did not affect plasma glucose levels and liver fructose contents; however, intestinal sucrose and fructose related mRNA levels were increased only in WT. In contrast, peritoneal fructose injection increased plasma glucose levels in both mice; however, the hepatic fructose content in KO was much higher owing to decreased hepatic Khk mRNA expression. Taken together, KO showed sucrose intolerance and fructose malabsorption owing to decreased gene expression.

  9. Wound Healing Is Impaired in MyD88-Deficient Mice

    PubMed Central

    Macedo, Lisa; Pinhal-Enfield, Grace; Alshits, Vera; Elson, Genie; Cronstein, Bruce Neil; Leibovich, Samuel Joseph

    2007-01-01

    Synergy between Toll-like receptor (TLR) and adenosine A2A receptor (A2AR) signaling switches macrophages from production of inflammatory cytokines such as tumor necrosis factor-α to production of the angiogenic growth factor vascular endothelial growth factor (VEGF). We show in this study that this switch critically requires signaling through MyD88, IRAK4, and TRAF6. Macrophages from mice lacking MyD88 (MyD88−/−) or IRAK4 (IRAK4−/−) lacked responsiveness to TLR agonists and did not respond to A2AR agonists by expressing VEGF. Suppression of TRAF6 expression with siRNA in RAW264.7 macrophages also blocked their response to TLR and A2AR agonists. Excisional skin wounds in MyD88−/− mice healed at a markedly slower rate than wounds in wild-type MyD88+/+ mice, showing delayed contraction, decreased and delayed granulation tissue formation, and reduced new blood vessel density. Although macrophages accumulated to higher levels in MyD88−/− wounds than in controls, expression of VEGF and HIF1-α mRNAs was elevated in MyD88+/+ wounds. CGS21680, an A2AR agonist, promoted repair in MyD88+/+ wounds and stimulated angiogenesis but had no significant effect on healing of MyD88−/− wounds. These results suggest that the synergistic interaction between TLR and A2AR signaling observed in vitro that switches macrophages from an inflammatory to an angiogenic phenotype also plays a role in wound healing in vivo. PMID:17974599

  10. Astrocytic Lrp4 (Low-Density Lipoprotein Receptor-Related Protein 4) Contributes to Ischemia-Induced Brain Injury by Regulating ATP Release and Adenosine-A2AR (Adenosine A2A Receptor) Signaling.

    PubMed

    Ye, Xin-Chun; Hu, Jin-Xia; Li, Lei; Li, Qiang; Tang, Fu-Lei; Lin, Sen; Sun, Dong; Sun, Xiang-Dong; Cui, Gui-Yun; Mei, Lin; Xiong, Wen-Cheng

    2018-01-01

    Lrp4 (low-density lipoprotein receptor-related protein 4) is predominantly expressed in astrocytes, where it regulates glutamatergic neurotransmission by suppressing ATP release. Here, we investigated Lrp4's function in ischemia/stroke-induced brain injury response, which includes glutamate-induced neuronal death and reactive astrogliosis. The brain-specific Lrp4 conditional knockout mice (Lrp4 GFAP-Cre ), astrocytic-specific Lrp4 conditional knockout mice (Lrp4 GFAP-creER ), and their control mice (Lrp4 f/f ) were subjected to photothrombotic ischemia and the transient middle cerebral artery occlusion. After ischemia/stroke, mice or their brain samples were subjected to behavior tests, brain histology, immunofluorescence staining, Western blot, and quantitative real-time polymerase chain reaction. In addition, primary astrocytes and neurons were cocultured with or without oxygen and glucose deprivation and in the presence or absence of the antagonist for adenosine-A 2A R (adenosine A2A receptor) or ATP-P2X7R (P2X purinoceptor 7) signaling. Gliotransmitters, such as glutamate, d-serine, ATP, and adenosine, in the condition medium of cultured astrocytes were also measured. Lrp4, largely expressed in astrocytes, was increased in response to ischemia/stroke. Both Lrp4 GFAP-Cre and Lrp4 GFAP-creER mice showed less brain injury, including reduced neuronal death, and impaired reactive astrogliosis. Mechanistically, Lrp4 conditional knockout in astrocytes increased ATP release and the production of ATP derivative, adenosine, which were further elevated by oxygen and glucose deprivation. Pharmacological inhibition of ATP-P 2 X 7 R or adenosine-A 2A R signaling diminished Lrp4 GFAP-creER 's protective effect. The astrocytic Lrp4 plays an important role in ischemic brain injury response. Lrp4 deficiency in astrocytes seems to be protective in response to ischemic brain injury, likely because of the increased ATP release and adenosine-A 2A R signaling. © 2017 American Heart

  11. Macrophage peroxisome proliferator-activated receptor γ deficiency delays skin wound healing through impairing apoptotic cell clearance in mice

    PubMed Central

    Chen, H; Shi, R; Luo, B; Yang, X; Qiu, L; Xiong, J; Jiang, M; Liu, Y; Zhang, Z; Wu, Y

    2015-01-01

    Skin wound macrophages are key regulators of skin repair and their dysfunction causes chronic, non-healing skin wounds. Peroxisome proliferator-activated receptor gamma (PPARγ) regulates pleiotropic functions of macrophages, but its contribution in skin wound healing is poorly defined. We observed that macrophage PPARγ expression was upregulated during skin wound healing. Furthermore, macrophage PPARγ deficiency (PPARγ-knock out (KO)) mice exhibited impaired skin wound healing with reduced collagen deposition, angiogenesis and granulation formation. The tumor necrosis factor alpha (TNF-α) expression in wounds of PPARγ-KO mice was significantly increased and local restoration of TNF-α reversed the healing deficit in PPARγ-KO mice. Wound macrophages produced higher levels of TNF-α in PPARγ-KO mice compared with control. In vitro, the higher production of TNF-α by PPARγ-KO macrophages was associated with impaired apoptotic cell clearance. Correspondingly, increased apoptotic cell accumulation was found in skin wound of PPARγ-KO mice. Mechanically, peritoneal and skin wound macrophages expressed lower levels of various phagocytosis-related molecules. In addition, PPARγ agonist accelerated wound healing and reduced local TNF-α expression and wound apoptotic cells accumulation in wild type but not PPARγ-KO mice. Therefore, PPARγ has a pivotal role in controlling wound macrophage clearance of apoptotic cells to ensure efficient skin wound healing, suggesting a potential new therapeutic target for skin wound healing. PMID:25590807

  12. Kv4.2 Knockout Mice Have Hippocampal-Dependent Learning and Memory Deficits

    ERIC Educational Resources Information Center

    Lugo, Joaquin N.; Brewster, Amy L.; Spencer, Corinne M.; Anderson, Anne E.

    2012-01-01

    Kv4.2 channels contribute to the transient, outward K[superscript +] current (A-type current) in hippocampal dendrites, and modulation of this current substantially alters dendritic excitability. Using Kv4.2 knockout (KO) mice, we examined the role of Kv4.2 in hippocampal-dependent learning and memory. We found that Kv4.2 KO mice showed a deficit…

  13. Serotonergic involvement in the amelioration of behavioral abnormalities in dopamine transporter knockout mice by nicotine.

    PubMed

    Uchiumi, Osamu; Kasahara, Yoshiyuki; Fukui, Asami; Hall, F Scott; Uhl, George R; Sora, Ichiro

    2013-01-01

    Dopamine transporter knockout (DAT KO) mice exhibit elevated extracellular dopamine levels in brain regions that include the striatum and the nucleus accumbens, but not the prefrontal cortex. DAT KO mice model some aspects of psychiatric disorders, including schizophrenia. Smoking is more common in patients with schizophrenia, suggesting that nicotine might ameliorate aspects of the behavioral abnormalities and/or treatment side effects seen in these individuals. We report nicotine-induced normalization of effects on locomotion and prepulse inhibition of acoustic startle (PPI) in DAT KO mice that require intact serotonin 5-HT1A systems. First, we observed that the marked hyperactivity displayed by DAT KO mice was reduced by administration of nicotine. This nicotine effect was blocked by pretreatment with the non-specific nicotinic acetylcholine (nACh) receptor antagonist mecamylamine, or the 5-HT1A antagonist WAY100635. Secondly, we examined the effects of nicotine on PPI in DAT KO mice. Treatment with nicotine significantly ameliorated the PPI deficits observed in DAT KO mice. The ameliorating action of nicotine on PPI deficits in DAT KO mice was blocked by mecamylamine, the α₇ nACh receptor antagonist methyllycaconitine or WAY100635, while the α₄β₂ nACh receptor antagonist dihydro-β-erythroidinehydrobromide (DHβE) produced only a non-significant trend toward attenuation of nicotine effects. Finally, we observed that administration of the 5-HT1A receptor agonist 8-OH-DPAT also ameliorated the deficit in PPI observed in DAT KO mice. This amelioration was antagonized by pretreatment with WAY100635. These data support the idea that nicotine might ameliorate some of the cognitive dysfunctions found in schizophrenia in a 5-HT1A-dependent fashion. This article is part of a Special Issue entitled 'Cognitive Enhancers'. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Disruption of BCAA metabolism in mice impairs exercise metabolism and endurance.

    PubMed

    She, Pengxiang; Zhou, Yingsheng; Zhang, Zhiyou; Griffin, Kathleen; Gowda, Kavitha; Lynch, Christopher J

    2010-04-01

    Exercise enhances branched-chain amino acid (BCAA) catabolism, and BCAA supplementation influences exercise metabolism. However, it remains controversial whether BCAA supplementation improves exercise endurance, and unknown whether the exercise endurance effect of BCAA supplementation requires catabolism of these amino acids. Therefore, we examined exercise capacity and intermediary metabolism in skeletal muscle of knockout (KO) mice of mitochondrial branched-chain aminotransferase (BCATm), which catalyzes the first step of BCAA catabolism. We found that BCATm KO mice were exercise intolerant with markedly decreased endurance to exhaustion. Their plasma lactate and lactate-to-pyruvate ratio in skeletal muscle during exercise and lactate release from hindlimb perfused with high concentrations of insulin and glucose were significantly higher in KO than wild-type (WT) mice. Plasma and muscle ammonia concentrations were also markedly higher in KO than WT mice during a brief bout of exercise. BCATm KO mice exhibited 43-79% declines in the muscle concentration of alanine, glutamine, aspartate, and glutamate at rest and during exercise. In response to exercise, the increments in muscle malate and alpha-ketoglutarate were greater in KO than WT mice. While muscle ATP concentration tended to be lower, muscle IMP concentration was sevenfold higher in KO compared with WT mice after a brief bout of exercise, suggesting elevated ammonia in KO is derived from the purine nucleotide cycle. These data suggest that disruption of BCAA transamination causes impaired malate/aspartate shuttle, thereby resulting in decreased alanine and glutamine formation, as well as increases in lactate-to-pyruvate ratio and ammonia in skeletal muscle. Thus BCAA metabolism may regulate exercise capacity in mice.

  15. Transspecies Transmission of Gammaretroviruses and the Origin of the Gibbon Ape Leukaemia Virus (GaLV) and the Koala Retrovirus (KoRV).

    PubMed

    Denner, Joachim

    2016-12-20

    Transspecies transmission of retroviruses is a frequent event, and the human immunodeficiency virus-1 (HIV-1) is a well-known example. The gibbon ape leukaemia virus (GaLV) and koala retrovirus (KoRV), two gammaretroviruses, are also the result of a transspecies transmission, however from a still unknown host. Related retroviruses have been found in Southeast Asian mice although the sequence similarity was limited. Viruses with a higher sequence homology were isolated from Melomys burtoni , the Australian and Indonesian grassland melomys. However, only the habitats of the koalas and the grassland melomys in Australia are overlapping, indicating that the melomys virus may not be the precursor of the GaLV. Viruses closely related to GaLV/KoRV were also detected in bats. Therefore, given the fact that the habitats of the gibbons in Thailand and the koalas in Australia are far away, and that bats are able to fly over long distances, the hypothesis that retroviruses of bats are the origin of GaLV and KoRV deserves consideration. Analysis of previous transspecies transmissions of retroviruses may help to evaluate the potential of transmission of related retroviruses in the future, e.g., that of porcine endogenous retroviruses (PERVs) during xenotransplantation using pig cells, tissues or organs.

  16. 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

  17. Low-Bone-Mass Phenotype of Deficient Mice for the Cluster of Differentiation 36 (CD36)

    PubMed Central

    Kevorkova, Olha; Martineau, Corine; Martin-Falstrault, Louise; Sanchez-Dardon, Jaime; Brissette, Louise; Moreau, Robert

    2013-01-01

    Bone tissue is continuously remodeled by bone cells and maintenance of its mass relies on the balance between the processes of resorption and formation. We have reported the expression of numerous scavenger receptors, namely scavenger receptor (SR) class B type I and II (SR-BI and SR-BII), and CD36, in bone-forming osteoblasts but their physiological roles in bone metabolism are still unknown. To unravel the role of CD36 in bone metabolism, we determined the bone phenotype of CD36 knockout (CD36KO) mice and characterized the cell functions of osteoblasts lacking CD36. Weights of CD36KO mice were significantly lower than corresponding wild-type (WT) mice, yet no significant difference was found in femoral nor tibial length between CD36KO and WT mice. Analysis of bone architecture by micro-computed tomography revealed a low bone mass phenotype in CD36KO mice of both genders. Femoral trabecular bone from 1 to 6 month-old CD36KO mice showed lower bone volume, higher trabecular separation and reduced trabeculae number compared to WT mice; similar alterations were noticed for lumbar vertebrae. Plasma levels of osteocalcin (OCN) and N-terminal propeptide of type I procollagen (PINP), two known markers of bone formation, were significantly lower in CD36KO mice than in WT mice, whereas plasma levels of bone resorption markers were similar. Accordingly, histology highlighted lower osteoblast perimeter and reduced bone formation rate. In vitro functional characterization of bone marrow stromal cells and osteoblasts isolated from CD36KO mice showed reduced cell culture expansion and survival, lower gene expression of osteoblastic Runt-related transcription factor 2 (Runx2) and osterix (Osx), as well as bone sialoprotein (BSP) and osteocalcin (OCN). Our results indicate that CD36 is mandatory for adequate bone metabolism, playing a role in osteoblast functions ensuring adequate bone formation. PMID:24204923

  18. Abnormal Type I Collagen Post-translational Modification and Crosslinking in a Cyclophilin B KO Mouse Model of Recessive Osteogenesis Imperfecta

    PubMed Central

    Cabral, Wayne A.; Perdivara, Irina; Weis, MaryAnn; Terajima, Masahiko; Blissett, Angela R.; Chang, Weizhong; Perosky, Joseph E.; Makareeva, Elena N.; Mertz, Edward L.; Leikin, Sergey; Tomer, Kenneth B.; Kozloff, Kenneth M.; Eyre, David R.; Yamauchi, Mitsuo; Marini, Joan C.

    2014-01-01

    Cyclophilin B (CyPB), encoded by PPIB, is an ER-resident peptidyl-prolyl cis-trans isomerase (PPIase) that functions independently and as a component of the collagen prolyl 3-hydroxylation complex. CyPB is proposed to be the major PPIase catalyzing the rate-limiting step in collagen folding. Mutations in PPIB cause recessively inherited osteogenesis imperfecta type IX, a moderately severe to lethal bone dysplasia. To investigate the role of CyPB in collagen folding and post-translational modifications, we generated Ppib−/− mice that recapitulate the OI phenotype. Knock-out (KO) mice are small, with reduced femoral areal bone mineral density (aBMD), bone volume per total volume (BV/TV) and mechanical properties, as well as increased femoral brittleness. Ppib transcripts are absent in skin, fibroblasts, femora and calvarial osteoblasts, and CyPB is absent from KO osteoblasts and fibroblasts on western blots. Only residual (2–11%) collagen prolyl 3-hydroxylation is detectable in KO cells and tissues. Collagen folds more slowly in the absence of CyPB, supporting its rate-limiting role in folding. However, treatment of KO cells with cyclosporine A causes further delay in folding, indicating the potential existence of another collagen PPIase. We confirmed and extended the reported role of CyPB in supporting collagen lysyl hydroxylase (LH1) activity. Ppib−/− fibroblast and osteoblast collagen has normal total lysyl hydroxylation, while increased collagen diglycosylation is observed. Liquid chromatography/mass spectrometry (LC/MS) analysis of bone and osteoblast type I collagen revealed site-specific alterations of helical lysine hydroxylation, in particular, significantly reduced hydroxylation of helical crosslinking residue K87. Consequently, underhydroxylated forms of di- and trivalent crosslinks are strikingly increased in KO bone, leading to increased total crosslinks and decreased helical hydroxylysine- to lysine-derived crosslink ratios. The altered

  19. Phosphodiesterase-1b (Pde1b) knockout mice are resistant to forced swim and tail suspension induced immobility and show upregulation of Pde10a.

    PubMed

    Hufgard, Jillian R; Williams, Michael T; Skelton, Matthew R; Grubisha, Olivera; Ferreira, Filipa M; Sanger, Helen; Wright, Mary E; Reed-Kessler, Tracy M; Rasmussen, Kurt; Duman, Ronald S; Vorhees, Charles V

    2017-06-01

    Major depressive disorder is a leading cause of suicide and disability. Despite this, current antidepressants provide insufficient efficacy in more than 60% of patients. Most current antidepressants are presynaptic reuptake inhibitors; postsynaptic signal regulation has not received as much attention as potential treatment targets. We examined the effects of disruption of the postsynaptic cyclic nucleotide hydrolyzing enzyme, phosphodiesterase (PDE) 1b, on depressive-like behavior and the effects on PDE1B protein in wild-type (WT) mice following stress. Littermate knockout (KO) and WT mice were tested in locomotor activity, tail suspension (TST), and forced swim tests (FST). FST was also used to compare the effects of two antidepressants, fluoxetine and bupropion, in KO versus WT mice. Messenger RNA (mRNA) expression changes were also determined. WT mice underwent acute or chronic stress and markers of stress and PDE1B expression were examined. Pde1b KO mice exhibited decreased TST and FST immobility. When treated with antidepressants, both WT and KO mice showed decreased FST immobility and the effect was additive in KO mice. Mice lacking Pde1b had increased striatal Pde10a mRNA expression. In WT mice, acute and chronic stress upregulated PDE1B expression while PDE10A expression was downregulated after chronic but not acute stress. PDE1B is a potential therapeutic target for depression treatment because of the antidepressant-like phenotype seen in Pde1b KO mice.

  20. Features of emotional and social behavioral phenotypes of calsyntenin2 knockout mice.

    PubMed

    Ranneva, S V; Pavlov, K S; Gromova, A V; Amstislavskaya, T G; Lipina, T V

    2017-08-14

    Calsyntenin-2 (Clstn2) is the synaptic protein that belongs to the super family of cadherins, playing an important role in learning and memory. We recently reported that Clstn2 knockout mice (Clstn2-KO) have a deficit of GABAergic interneurons coupled with hyperactivity and deficient spatial memory. Given, that impaired functioning of GABA receptors is linked to several psychopathologies, including anxiety and autism, we sought to further characterize Clstn2-KO mice with respect to emotional and social behavior. Clstn2-KO males and females were tested in the elevated plus-maze (EPM), open field (OF), forced swim test, social affiliation and recognition test, social transmission of food preference (STFP), dyadic social interactions and marble burying test. Clstn2-KO mice demonstrated high exploration and hyperactivity in the dimly lit EPM that affect anxiety parameters. In contrast, in a more adverse situation in the OF have increased emotionality in Clstn2-KO males, not females. Assessment of hyperactivity for prolong period in the OF showed that Clstn2-KO animals were able to decline their hyperactivity, but their ambulation still remained higher than in WT littermates. Additionally, Clstn2-KO mice expressed stereotyped behavior. Strikingly, analysis of social behavior identified deficient social motivation and social recognition only in Clstn2-KO males, but not in females. Further analysis of social communication in the STFP and direct observation of agonistic interactions confirmed the reduced social behavior in Clstn2-KO males. Altogether, current results showed Clstn2 gene and sex interactions on socio-emotional performance in mice, suggesting a possible role of calsyntenin2 in psychopathological mechanisms of autism. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Enhanced ethanol fermentation of brewery wastewater using the genetically modified strain E. coli KO11.

    PubMed

    Rao, Kripa; Chaudhari, Vaibhav; Varanasi, Sasidhar; Kim, Dong-Shik

    2007-02-01

    We have used liquid waste obtained from a beer brewery process to produce ethanol. To increase the productivity, genetically modified organism, Escherichia coli KO11, was used for ethanol fermentation. Yeast was also used to produce ethanol from the same feed stock, and the ethanol production rates and resulting concentrations of sugars and ethanol were compared with those of KO11. In the experiments, first the raw wastewater was directly fermented using two strains with no saccharification enzymes added. Then, commercial enzymes, alpha-amylase, pectinase, or a combination of both, were used for simultaneous saccharification and fermentation, and the results were compared with those of the no-enzyme experiments for KO11 and yeast. Under the given conditions with or without the enzymes, yeast produced ethanol more rapidly than E. coli KO11, but the final ethanol concentrations were almost the same. For both yeast and KO11, the enzymes were observed to enhance the ethanol yields by 61-84% as compared to the fermentation without enzymes. The combination of the two enzymes increased ethanol production the most for the both strains. The advantages of using KO11 were not demonstrated clearly as compared to the yeast fermentation results.

  2. Oxytocin null mice ingest enhanced amounts of sweet solutions during light and dark cycles and during repeated shaker stress.

    PubMed

    Billings, Lyndsey B; Spero, Jonathan A; Vollmer, Regis R; Amico, Janet A

    2006-07-15

    Central oxytocin (OT) pathways appear to limit consumption of sweet solutions. Male and female C57BL/6 mice that lack the gene for oxytocin (OT KO mice) displayed an initial and sustained enhanced intake of sucrose solution over water compared to wild type (WT) mice when the solutions were presented as a two-bottle choice [Amico JA, Vollmer RR, Cai HM, Miedlar JA, Rinaman R. Enhanced initial and sustained intake of sucrose solution in mice with an oxytocin gene deletion. Am J Physiol: Regul Integr Comp Physiol 2005;289:R1798-806]. In this study we examined the ingestion of a non-nutritive sweetener, 0.2% saccharin in sucrose-experienced OT KO and WT mice given a two-bottle choice between saccharin solution and water available ad libitum for 4 days. Compared to WT mice, OT KO mice consumed significantly greater volumes of saccharin solution during the dark and light photoperiods on the first day and subsequent days of the study. The results were replicated when the experiment was repeated in the same animals. In another experiment, we determined that daily exposure to platform shaker stress did not alter the marked sucrose consumption in OT KO mice. OT KO mice drank significantly more sucrose than WT mice during periods of stress and non-stress. We conclude that the avid consumption of sweetened solutions by OT KO mice is not restricted to a single photoperiod, occurs independent of caloric content of the sweetened solution, and is not altered by exposure to the daily stress of platform shaker. The cumulative results from our studies of sucrose and saccharin ingestion in OT KO and WT male and female mice suggest a special role for sweet taste in the recruitment of OT neurons.

  3. Enhanced initial and sustained intake of sucrose solution in mice with an oxytocin gene deletion.

    PubMed

    Amico, Janet A; Vollmer, Regis R; Cai, Hou-ming; Miedlar, Julie A; Rinaman, Linda

    2005-12-01

    Laboratory mice drink little sucrose solution on initial exposure, but later develop a strong preference for sucrose over water that plateaus after a few days. Both the initial neophobia and later plateau of sucrose intake may involve central oxytocin (OT) signaling pathways. If so, then mice that lack the gene for OT [OT knockout (KO)] should exhibit enhanced initial and sustained sucrose intake compared with wild-type (WT) cohorts. To test this hypothesis, female OT KO and WT mice (11-13 mo old) were given a two-bottle choice between 10% sucrose and water available ad libitum for 4 days. On the first day, sucrose intake was 20-fold greater in OT KO mice compared with WT cohorts. The avid sucrose consumption by OT KO mice increased further on day 2 and was sustained at significantly higher levels than intake by WT mice. Enhanced initial and sustained sucrose intake also was observed in 5- to 7-mo-old male OT KO mice. The effect of genotype was observed over a range of sucrose concentrations and was maintained over at least 8 days of continual exposure. However, there was no effect of genotype on daily intake of sucrose-enriched powdered chow. These findings indicate that the genetic absence of OT in mice is associated with enhanced initial and sustained intake of sucrose solutions. Thus central OT pathways may normally participate in limiting initial intake of novel ingesta and may also participate in limiting intake of sweet, highly palatable familiar ingesta.

  4. Energy metabolism and thyroid function of mice with deleted wolframin (Wfs1) gene.

    PubMed

    Noormets, K; Kõks, S; Ivask, M; Aunapuu, M; Arend, A; Vasar, E; Tillmann, V

    2014-05-01

    There is no data about the energy metabolism of patients with Wolfram syndrome caused by mutations in the wolframin (Wfs1) gene. The aim of this study was to investigate the role of Wfs1 in energy metabolism and thyroid function in Wfs1 deficient mice (Wfs1KO). 16 male (8 Wfs1KO, 8 wild type (wt)) and 16 female (8 Wfs1KO, 8wt) mice aged 11-13 weeks were studied alone in a specific metabolic cage for 48 h. Body weight, food, water and O2 consumption, motor activity, CO2 and heat production of mice were recorded. At the age of 14-20 weeks, plasma levels of thyroxine (T4), TSH and leptin were measured and histology of thyroid tissues examined. Mean CO2 and heat production was not different between the groups. Mean O2 consumption was higher in the Wfs1KO females compared to the Wfs1KO males (3 410.0±127.0 vs. 2 806.0±82.4 ml/kg/h; p<0.05), but not compared to the wt mice. The mean movement activity was not different between the groups except that the Wfs1KO females reared up more often than the wt females (199.8±63.46 vs. 39.26±24.71 cnts/48 h; p<0.05). Both male and female Wfs1KO mice had significantly lower body mass and food intake than wt mice. Male Wfs1KO mice also lost more weight in metabolic cage than wt males (20.43±0.41 vs. 16.07±0.86%; p<0.05) indicating more pronounced response to isolation. Male Wfs1KO mice had significantly lower levels of plasma leptin than wt male mice (3.37±0.40 vs. 5.82±0.71 ng/ml; p<0.01). Thyroid function measured by serum TSH and T4 levels was not different between Wfs1KO and wt groups, but both Wfs1KO and wt male mice had significantly higher mean T4 levels than female mice. The histology of thyroid tissue of Wfs1KO males showed a trend to a smaller mean number of epithelial cells per follicle than the wt male mice.Although Wfs1KO mice were smaller and lost more weight during the experiment, their energy metabolism was not different from wt mice except that the female Wfs1KO mice consumed more O2. As mice in

  5. Low-Salt Diet and Circadian Dysfunction Synergize to Induce Angiotensin II-Dependent Hypertension in Mice.

    PubMed

    Pati, Paramita; Fulton, David J R; Bagi, Zsolt; Chen, Feng; Wang, Yusi; Kitchens, Julia; Cassis, Lisa A; Stepp, David W; Rudic, R Daniel

    2016-03-01

    Blood pressure exhibits a robust circadian rhythm in health. In hypertension, sleep apnea, and even shift work, this balanced rhythm is perturbed via elevations in night-time blood pressure, inflicting silent damage to the vasculature and body organs. Herein, we examined the influence of circadian dysfunction during experimental hypertension in mice. Using radiotelemetry to measure ambulatory blood pressure and activity, the effects of angiotensin II administration were studied in wild-type (WT) and period isoform knockout (KO) mice (Per2-KO, Per2, 3-KO, and Per1, 2, 3-KO/Per triple KO [TKO] mice). On a normal diet, administration of angiotensin II caused nondipping blood pressure and exacerbated vascular hypertrophy in the Period isoform KO mice relative to WT mice. To study the endogenous effects of angiotensin II stimulation, we then administered a low-salt diet to the mice, which does stimulate endogenous angiotensin II in addition to lowering blood pressure. A low-salt diet decreased blood pressure in wild-type mice. In contrast, Period isoform KO mice lost their circadian rhythm in blood pressure on a low-salt diet, because of an increase in resting blood pressure, which was restorable to rhythmicity by the angiotensin receptor blocker losartan. Chronic administration of low salt caused vascular hypertrophy in Period isoform KO mice, which also exhibited increased renin levels and altered angiotensin 1 receptor expression. These data suggest that circadian clock genes may act to inhibit or control renin/angiotensin signaling. Moreover, circadian disorders such as sleep apnea and shift work may alter the homeostatic responses to sodium restriction to potentially influence nocturnal hypertension. © 2016 American Heart Association, Inc.

  6. β-Catenin is Essential for Ethanol Metabolism and Protection Against Alcohol-mediated Liver Steatosis in Mice

    PubMed Central

    Liu, Shiguang; Yeh, Tzu-Hsuan; Singh, Vijay P.; Shiva, Sruti; Krauland, Lindsay; Li, Huanan; Zhang, Pili; Kharbanda, Kusum; Ritov, Vladimir; Monga, Satdarshan P. S.; Scott, Donald K.; Eagon, Patricia K.; Behari, Jaideep

    2011-01-01

    The liver plays a central role in ethanol metabolism and oxidative stress is implicated in alcohol-mediated liver injury. β-Catenin regulates hepatic metabolic zonation and adaptive response to oxidative stress. We hypothesized that β-catenin regulates the hepatic response to ethanol ingestion. Female liver-specific β-catenin knockout (KO) mice and wild type (WT) littermates were fed the Lieber-Decarli liquid diet (5% ethanol) in a pair-wise fashion. Liver histology, biochemistry, and gene expression studies were performed. Plasma alcohol and ammonia levels were measured using standard assays. Ethanol-fed KO mice exhibited systemic toxicity and early mortality. KO mice exhibited severe macrovesicular steatosis and five to six-fold higher serum ALT and AST levels. KO mice had modest increase in hepatic oxidative stress, lower expression of mitochondrial superoxide dismutase (SOD-2), and lower citrate synthase activity, the first step in the tricarboxylic acid cycle. N-Acetyl cysteine (NAC) did not prevent ethanol-induced mortality in KO mice. In WT livers, β-catenin was found to co-precipitate with FoxO3, the upstream regulator of SOD-2. Hepatic alcohol dehydrogenase and aldehyde dehydrogenase activities and expression were lower in KO mice. Hepatic cytochrome P450 2E1 protein levels were upregulated in ethanol-fed WT mice but were nearly undetectable in KO mice. These changes in ethanol-metabolizing enzymes were associated with 30-fold higher blood alcohol levels in KO mice. Conclusion β-catenin is essential for hepatic ethanol metabolism and plays a protective role in alcohol-mediated liver steatosis. Our results strongly suggest that integration of these functions by β-catenin is critical for adaptation to ethanol ingestion in vivo. PMID:22031168

  7. Aggressive mammary carcinoma progression in Nrf2 knockout mice treated with 7,12-dimethylbenz[a]anthracene

    PubMed Central

    2010-01-01

    Background Activation of nuclear factor erythroid 2-related factor (Nrf2), which belongs to the basic leucine zipper transcription factor family, is a strategy for cancer chemopreventive phytochemicals. It is an important regulator of genes induced by oxidative stress, such as glutathione S-transferases, heme oxygenase-1 and peroxiredoxin 1, by activating the antioxidant response element (ARE). We hypothesized that (1) the citrus coumarin auraptene may suppress premalignant mammary lesions via activation of Nrf2/ARE, and (2) that Nrf2 knockout (KO) mice would be more susceptible to mammary carcinogenesis. Methods Premalignant lesions and mammary carcinomas were induced by medroxyprogesterone acetate and 7,12-dimethylbenz[a]anthracene treatment. The 10-week pre-malignant study was performed in which 8 groups of 10 each female wild-type (WT) and KO mice were fed either control diet or diets containing auraptene (500 ppm). A carcinogenesis study was also conducted in KO vs. WT mice (n = 30-34). Comparisons between groups were evaluated using ANOVA and Kaplan-Meier Survival statistics, and the Mann-Whitney U-test. Results All mice treated with carcinogen exhibited premalignant lesions but there were no differences by genotype or diet. In the KO mice, there was a dramatic increase in mammary carcinoma growth rate, size, and weight. Although there was no difference in overall survival, the KO mice had significantly lower mammary tumor-free survival. Also, in the KO mammary carcinomas, the active forms of NF-κB and β-catenin were increased ~2-fold whereas no differences in oxidized proteins were observed. Many other tumors were observed, including lymphomas. Interestingly, the incidences of lung adenomas in the KO mice were significantly higher than in the WT mice. Conclusions We report, for the first time, that there was no apparent difference in the formation of premalignant lesions, but rather, the KO mice exhibited rapid, aggressive mammary carcinoma progression

  8. Interactions of PPAR α and GLUT4 in DOCA/salt-induced renal injury in mice.

    PubMed

    Ighodaro, Igbe; Eric, Omogbai Kelly; Adebayo, Oyekan

    2013-12-20

    Diminished insulin sensitivity is a characteristic feature of various pathological conditions such as hypertension and activation of peroxisome proliferator activated receptor α (PPARα) has been shown to enhance insulin resistance and reduce capacity for glucose uptake in muscles. The present study was designed to evaluate the interactions of PPARα and GLUT4 in a model of hypertensive renal injury by studying deoxycorticosterone acetate (DOCA)-salt induced hypertension in wild-type (WT) and PPARα knockout (KO) mice. PPARα WT and KO mice were uninephrectomized (UNx) and implanted subcutaneously DOCA and drank 1% sodium chloride/1% potassium chloride with or without a GLUT4 antagonist, indinavir (20 mg/kg/day, s.c) or PPARα ligand, fenofibrate (100 mg/kg/day, orally). DOCA/salt treatment increased urinary sodium excretion and urine volume (p<0.05) in PPARα KO mice compared to WT littermates. Indinavir increased proteinuria (p<0.01) in DOCA/salt-treated PPARα KO mice compared to WT littermates but did not affect heart and kidney weight index in DOCA/salt KO or WT-treated mice. Urinary sodium excretion (UNaV) and urine volume (UV) were increased by indinavir (p<0.01) and fenofibrate (p<0.05) in DOCA/salt-treated PPARα KO mice compared to WT mice. Urinary nitric oxide was greater in both fenofibrate (p<0.05) and indinavir-treated WT mice (p<0.05) compared to KO mice. These data suggest that in hypertensive nephropathy, GLUT4 probably exerts a renoprotective role that was enhanced with the activation of PPARα receptors by a mechanism that may be related to increased nitric oxide production.

  9. Role of METTL20 in regulating β-oxidation and heat production in mice under fasting or ketogenic conditions.

    PubMed

    Shimazu, Tadahiro; Furuse, Tamio; Balan, Shabeesh; Yamada, Ikuko; Okuno, Shuzo; Iwanari, Hiroko; Suzuki, Takehiro; Hamakubo, Takao; Dohmae, Naoshi; Yoshikawa, Takeo; Wakana, Shigeharu; Shinkai, Yoichi

    2018-01-19

    METTL20 is a seven-β-strand methyltransferase that is localised to the mitochondria and tri-methylates the electron transfer flavoprotein (ETF) β subunit (ETFB) at lysines 200 and 203. It has been shown that METTL20 decreases the ability of ETF to extract electrons from medium-chain acyl-coenzyme A (CoA) dehydrogenase (MCAD) and glutaryl-CoA dehydrogenase in vitro. METTL20-mediated methylation of ETFB influences the oxygen consumption rate in permeabilised mitochondria, suggesting that METTL20-mediated ETFB methylation may also play a regulatory role in mitochondrial metabolism. In this study, we generated Mettl20 knockout (KO) mice to uncover the in vivo functions of METTL20. The KO mice were viable, and a loss of ETFB methylation was confirmed. In vitro enzymatic assays revealed that mitochondrial ETF activity was higher in the KO mice than in wild-type mice, suggesting that the KO mice had higher β-oxidation capacity. Calorimetric analysis showed that the KO mice fed a ketogenic diet had higher oxygen consumption and heat production. A subsequent cold tolerance test conducted after 24 h of fasting indicated that the KO mice had a better ability to maintain their body temperature in cold environments. Thus, METTL20 regulates ETF activity and heat production through lysine methylation when β-oxidation is highly activated.

  10. 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

  11. Genetic ablation of myelin protein zero-like 3 in mice increases energy expenditure, improves glycemic control, and reduces hepatic lipid synthesis.

    PubMed

    Czyzyk, Traci A; Andrews, Jessica L; Coskun, Tamer; Wade, Mark R; Hawkins, Eric D; Lockwood, John F; Varga, Gabor; Sahr, Allison E; Chen, Yanyun; Brozinick, Joseph T; Kikly, Kristine; Statnick, Michael A

    2013-07-15

    Obesity continues to be a global health problem, and thus it is imperative that new pathways regulating energy balance be identified. Recently, it was reported: (Hayashi K, Cao T, Passmore H, Jourdan-Le Saux C, Fogelgren B, Khan S, Hornstra I, Kim Y, Hayashi M, Csiszar K. J Invest Dermatol 123: 864-871, 2004) that mice carrying a missense mutation in myelin protein zero-like 3 (Mpzl3rc) have reduced body weight. To determine how Mpzl3 controls energy balance in vivo, we generated mice deficient in myelin protein zero-like 3 (Mpzl3-KO). Interestingly, KO mice were hyperphagic yet had reduced body weight and fat mass. Moreover, KO mice were highly resistant to body weight and fat mass gain after exposure to a high-fat, energy-dense diet. These effects on body weight and adiposity were driven, in part, by a pronounced increase in whole body energy expenditure levels in KO mice. KO mice also had reduced blood glucose levels during an intraperitoneal glucose challenge and significant reductions in circulating insulin levels suggesting an increase in insulin sensitivity. In addition, there was an overall increase in oxidative capacity and contractile force in skeletal muscle isolated from KO mice. Hepatic triglyceride levels were reduced by 92% in livers of KO mice, in part due to a reduction in de novo lipid synthesis. Interestingly, Mpzl3 mRNA expression in liver was increased in diet-induced obese mice. Moreover, KO mice exhibited an increase in insulin-stimulated Akt signaling in the liver, further demonstrating that Mpzl3 can regulate insulin sensitivity in this tissue. We have determined that Mpzl3 has a novel physiological role in controlling body weight regulation, energy expenditure, glycemic control, and hepatic triglyceride synthesis in mice.

  12. What have we learned about GPER function in physiology and disease from knockout mice?

    PubMed Central

    Prossnitz, Eric R.; Hathaway, Helen J.

    2015-01-01

    Estrogens, predominantly 17β-estradiol, exert diverse effects throughout the body in both normal and patho-physiology, during development and in reproductive, metabolic, endocrine, cardiovascular, nervous, musculoskeletal and immune systems. Estrogen and its receptors also play important roles in carcinogenesis and therapy, particularly for breast cancer. In addition to the classical nuclear estrogen receptors (ERα and ERβ) that traditionally mediate predominantly genomic signaling, the G protein-coupled estrogen receptor GPER has become recognized as a critical mediator of rapid signaling in response to estrogen. Mouse models, and in particular knockout (KO) mice, represent an important approach to understand the functions of receptors in normal physiology and disease. Whereas ERα KO mice display multiple significant defects in reproduction and mammary gland development, ERβ KO phenotypes are more limited, and GPER KO exhibit no reproductive deficits. However, the study of GPER KO mice over the last six years has revealed that GPER deficiency results in multiple physiological alterations including obesity, cardiovascular dysfunction, insulin resistance and glucose intolerance. In addition, the lack of estrogen-mediated effects in numerous tissues of GPER KO mice, studied in vivo or ex vivo, including those of the cardiovascular, endocrine, nervous and immune systems, reveals GPER as a genuine mediator of estrogen action. Importantly, GPER KO mice have also revealed roles for GPER in breast carcinogenesis and metastasis. In combination with the supporting effects of GPER-selective ligands and GPER knockdown approaches, GPER KO mice demonstrate the therapeutic potential of targeting GPER activity in diseases as diverse as obesity, diabetes, multiple sclerosis, hypertension, atherosclerosis, myocardial infarction, stroke and cancer. PMID:26189910

  13. Functional β-Adrenoceptors Are Important for Early Muscle Regeneration in Mice through Effects on Myoblast Proliferation and Differentiation

    PubMed Central

    Church, Jarrod E.; Trieu, Jennifer; Sheorey, Radhika; Chee, Annabel Y. -M.; Naim, Timur; Baum, Dale M.; Ryall, James G.; Gregorevic, Paul; Lynch, Gordon S.

    2014-01-01

    Muscles can be injured in different ways and the trauma and subsequent loss of function and physical capacity can impact significantly on the lives of patients through physical impairments and compromised quality of life. The relative success of muscle repair after injury will largely determine the extent of functional recovery. Unfortunately, regenerative processes are often slow and incomplete, and so developing novel strategies to enhance muscle regeneration is important. While the capacity to enhance muscle repair by stimulating β2-adrenoceptors (β-ARs) using β2-AR agonists (β2-agonists) has been demonstrated previously, the exact role β-ARs play in regulating the regenerative process remains unclear. To investigate β-AR-mediated signaling in muscle regeneration after myotoxic damage, we examined the regenerative capacity of tibialis anterior and extensor digitorum longus muscles from mice lacking either β1-AR (β1-KO) and/or β2-ARs (β2-KO), testing the hypothesis that muscles from mice lacking the β2-AR would exhibit impaired functional regeneration after damage compared with muscles from β1-KO or β1/β2-AR null (β1/β2-KO) KO mice. At 7 days post-injury, regenerating muscles from β1/β2-KO mice produced less force than those of controls but muscles from β1-KO or β2-KO mice did not exhibit any delay in functional restoration. Compared with controls, β1/β2-KO mice exhibited an enhanced inflammatory response to injury, which delayed early muscle regeneration, but an enhanced myoblast proliferation later during regeneration ensured a similar functional recovery (to controls) by 14 days post-injury. This apparent redundancy in the β-AR signaling pathway was unexpected and may have important implications for manipulating β-AR signaling to improve the rate, extent and efficacy of muscle regeneration to enhance functional recovery after injury. PMID:25000590

  14. Role of CB2 receptors in social and aggressive behavior in male mice.

    PubMed

    Rodríguez-Arias, Marta; Navarrete, Francisco; Blanco-Gandia, M Carmen; Arenas, M Carmen; Aguilar, María A; Bartoll-Andrés, Adrián; Valverde, Olga; Miñarro, José; Manzanares, Jorge

    2015-08-01

    Male CB1KO mice exhibit stronger aggressive responses than wild-type mice. This study was designed to examine the role of cannabinoid CB2r in social and aggressive behavior. The social interaction test and resident-intruder paradigm were performed in mice lacking CB2r (CB2KO) and in wild-type (WT) littermates. The effects of the CB2r selective agonist JWH133 (1 and 2 mg/kg) on aggression were also evaluated in Oncins France 1 (OF1) mice. Gene expression analyses of monoamine oxidase-A (MAO-A), catechol-o-methyltransferase (COMT), 5-hydroxytryptamine transporter (5-HTT), and 5-HT1B receptor (5HT1Br) in the dorsal raphe nuclei (DR) and the amygdala (AMY) were carried out using real-time PCR. Group-housed CB2KO mice exhibited higher levels of aggression in the social interaction test and displayed more aggression than resident WT mice. Isolation increased aggressive behavior in WT mice but did not affect CB2KO animals; however, the latter mice exhibited higher levels of social interaction with their WT counterparts. MAO-A and 5-HTT gene expression was significantly higher in grouped CB2KO mice. The expression of 5HT1Br, COMT, and MAO-A in the AMY was more pronounced in CB2KO mice than in WT counterparts. Acute administration of the CB2 agonist JWH133 significantly reduced the level of aggression in aggressive isolated OF1 mice, an effect that decreased after pretreatment with the CB2 receptor antagonist AM630. Our results suggest that CB2r is implicated in social interaction and aggressive behavior and deserves further consideration as a potential new target for the management of aggression.

  15. Host resistance of CD18 knockout mice against systemic infection with Listeria monocytogenes

    NASA Technical Reports Server (NTRS)

    Wu, Huaizhu; Prince, Joseph E.; Brayton, Cory F.; Shah, Chirayu; Zeve, Daniel; Gregory, Stephen H.; Smith, C. Wayne; Ballantyne, Christie M.

    2003-01-01

    Mice with targeted mutations of CD18, the common beta2 subunit of CD11/CD18 integrins, have leukocytosis, impaired transendothelial neutrophil emigration, and reduced host defense to Streptococcus pneumoniae, a gram-positive extracellular bacterium. Previous studies using blocking monoclonal antibodies suggested roles for CD18 and CD11b in hepatic neutrophil recruitment and host innate response to Listeria monocytogenes, a gram-positive intracellular bacterium. We induced systemic listeriosis in CD18 knockout (CD18-ko) and wild-type (WT) mice by tail vein injection with Listeria. By 14 days postinjection (dpi), 8 of 10 WT mice died, compared with 2 of 10 CD18-ko mice (P < 0.01). Quantitative organ culture showed that numbers of Listeria organisms in livers and spleens were similar in both groups at 20 min postinfection. By 3, 5, and 7 dpi, however, numbers of Listeria organisms were significantly lower in livers and spleens of CD18-ko mice than in WT mice. Histopathology showed that following Listeria infection, CD18-ko mice had milder inflammatory and necrotizing lesions in both spleens and livers than did WT mice. Cytokine assays indicated that baseline interleukin-1beta and granulocyte colony-stimulating factor (G-CSF) levels were higher in CD18-ko mice than in WT mice and that CD18-ko splenocytes produced higher levels of interleukin-1beta and G-CSF than WT splenocytes under the same amount of Listeria stimulation. These findings show that CD18 is not an absolute requirement for antilisterial innate immunity or hepatic neutrophil recruitment. We propose that the absence of CD18 in the mice results in the priming of innate immunity, as evidenced by elevated cytokine expression, and neutrophilic leukocytosis, which augments antilisterial defense.

  16. Sucrose and monosodium glutamate taste thresholds and discrimination ability of T1R3 knockout mice.

    PubMed

    Delay, E R; Hernandez, N P; Bromley, K; Margolskee, R F

    2006-05-01

    Molecular and behavioral studies have identified heterodimers of the T1R family as receptors for detecting the tastes of sweet (T1R2 + T1R3) and umami (T1R1 + T1R3). However, behavioral studies have reported conflicting findings with T1R3 knockout (KO) mice. One study showed a complete or nearly complete loss of preference for sweet and umami substances by KO mice, whereas KO mice in another study showed only a partial reduction in preferences for sucrose and monosodium glutamate (MSG), the prototypical umami substance. The present experiments used psychophysical methods to assess how sensitive T1R1-KO mice are to sucrose and MSG and discrimination methods to determine if these mice could distinguish between the tastes of sucrose and MSG. Detection thresholds of T1R3-KO mice and wild-type (WT) C57Bl mice were nearly identical for sucrose and MSG. Mice of both genotypes were easily able to discriminate between the tastes of sucrose and MSG. When amiloride (a sodium channel blocker) was added to all solutions to reduce the taste of Na+, discrimination accuracy of both genotypes of mice decreased but more so for the T1R3-KO mice than the WT mice. However, even when the sodium taste of MSG was neutralized, both genotypes could still discriminate between the two substances well above chance performance. These results suggest that sucrose and MSG can be detected by taste receptors other than T1R2 + T1R3 and T1R1 + T1R3 and that the conflicts between the previous studies may have been due to the methodological limitations.

  17. Deletion of Adenosine A2A Receptors from Astrocytes Disrupts Glutamate Homeostasis Leading to Psychomotor and Cognitive Impairment: Relevance to Schizophrenia

    PubMed Central

    Matos, Marco; Shen, Hai-Ying; Augusto, Elisabete; Wang, Yumei; Wei, Catherine J.; Wang, Yu Tian; Agostinho, Paula; Boison, Detlev; Cunha, Rodrigo A.; Chen, Jiang-Fan

    2016-01-01

    BACKGROUND Adenosine A2A receptors (A2AR) modulate dopamine and glutamate signaling and thereby may influence some of the psychomotor and cognitive processes associated with schizophrenia. Because astroglial A2AR regulate the availability of glutamate, we hypothesized that they might play an unprecedented role in some of the processes leading to the development of schizophrenia, which we investigated using a mouse line with a selective deletion of A2AR in astrocytes (Gfa2-A2AR knockout [KO] mice]. METHODS We examined Gfa2-A2AR KO mice for behaviors thought to recapitulate some features of schizophrenia, namely enhanced MK-801 psychomotor response (positive symptoms) and decreased working memory (cognitive symptoms). In addition, we probed for neurochemical alterations in the glutamatergic circuitry, evaluating glutamate uptake and release and the levels of key proteins defining glutamatergic signaling (glutamate transporter-I [GLT-I], N-methyl-D-aspartate receptors [NMDA-R] and α-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors [AMPA-R]) to provide a mechanistic understanding of the phenotype encountered. RESULTS We show that Gfa2-A2AR KO mice exhibited enhanced MK-801 psychomotor response and decreased working memory; this was accompanied by a disruption of glutamate homeostasis characterized by aberrant GLT-I activity, increased presynaptic glutamate release, NMDA-R 2B subunit upregulation, and increased internalization of AMPA-R. Accordingly, selective GLT-I inhibition or blockade of GluR1/2 endocytosis prevented the psychomotor and cognitive phenotypes in Gfa2-A2AR KO mice, namely in the nucleus accumbens. CONCLUSIONS These results show that the dysfunction of astrocytic A2AR, by controlling GLT-I activity, triggers an astrocyte-to-neuron wave of communication resulting in disrupted glutamate homeostasis, thought to underlie several endophenotypes relevant to schizophrenia. PMID:25869810

  18. Deletion of adenosine A2A receptors from astrocytes disrupts glutamate homeostasis leading to psychomotor and cognitive impairment: relevance to schizophrenia.

    PubMed

    Matos, Marco; Shen, Hai-Ying; Augusto, Elisabete; Wang, Yumei; Wei, Catherine J; Wang, Yu Tian; Agostinho, Paula; Boison, Detlev; Cunha, Rodrigo A; Chen, Jiang-Fan

    2015-12-01

    Adenosine A2A receptors (A2AR) modulate dopamine and glutamate signaling and thereby may influence some of the psychomotor and cognitive processes associated with schizophrenia. Because astroglial A2AR regulate the availability of glutamate, we hypothesized that they might play an unprecedented role in some of the processes leading to the development of schizophrenia, which we investigated using a mouse line with a selective deletion of A2AR in astrocytes (Gfa2-A2AR knockout [KO] mice]. We examined Gfa2-A2AR KO mice for behaviors thought to recapitulate some features of schizophrenia, namely enhanced MK-801 psychomotor response (positive symptoms) and decreased working memory (cognitive symptoms). In addition, we probed for neurochemical alterations in the glutamatergic circuitry, evaluating glutamate uptake and release and the levels of key proteins defining glutamatergic signaling (glutamate transporter-I [GLT-I], N-methyl-D-aspartate receptors [NMDA-R] and α-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors [AMPA-R]) to provide a mechanistic understanding of the phenotype encountered. We show that Gfa2-A2AR KO mice exhibited enhanced MK-801 psychomotor response and decreased working memory; this was accompanied by a disruption of glutamate homeostasis characterized by aberrant GLT-I activity, increased presynaptic glutamate release, NMDA-R 2B subunit upregulation, and increased internalization of AMPA-R. Accordingly, selective GLT-I inhibition or blockade of GluR1/2 endocytosis prevented the psychomotor and cognitive phenotypes in Gfa2-A2AR KO mice, namely in the nucleus accumbens. These results show that the dysfunction of astrocytic A2AR, by controlling GLT-I activity, triggers an astrocyte-to-neuron wave of communication resulting in disrupted glutamate homeostasis, thought to underlie several endophenotypes relevant to schizophrenia. Copyright © 2015. Published by Elsevier Inc.

  19. Piroxicam treatment augments bone abnormalities in interleukin-10 knockout mice.

    PubMed

    Holgersen, Kristine; Dobie, Ross; Farquharson, Colin; vanʼt Hof, Rob; Ahmed, Syed Faisal; Hansen, Axel Kornerup; Holm, Thomas L

    2015-02-01

    Osteoporosis and fractures are common complications of inflammatory bowel disease. The pathogenesis is multifactorial and has been partly attributed to intestinal inflammation. The aim of this study was to evaluate bone status and assess the association between bone loss and gut inflammation in an experimental colitis model. Colitis was induced in interleukin-10 knockout mice (PAC IL-10 k.o.) by peroral administration of piroxicam for 12 days. The degree of colitis was assessed by clinical, macroscopic, and microscopic evaluation. Trabecular and cortical bone microarchitecture of tibia were determined using micro-computed tomography. Moreover, the serum levels of bone formation and bone resorption biomarkers were measured, and inflammatory protein profiling was performed on colons. PAC IL-10 k.o. mice developed severe colitis, characterized by hyperplasia and focal transmural inflammation, which was consistent with Crohn's disease-like pathology. The gut inflammation was accompanied by a 14% and 12% reduction in trabecular thickness relative to piroxicam-treated wild type and untreated wild type mice, respectively (P < 0.001). The trabecular bone structure was also changed in PAC IL-10 k.o. mice, whereas no differences in cortical bone geometry were observed. The trabecular thickness was inversely correlated with serum levels of CTX (r = -0.93, P = 0.006). Moreover, numerous inflammatory mediators, including RANKL and osteoprotegerin, were significantly increased in the colon of PAC IL-10 k.o. mice. PAC IL-10 k.o. mice develop bone loss and changed trabecular structure, as a result of increased bone resorption. Thus, the PAC IL-10 k.o. model could be a useful experimental model in preclinical research of inflammatory bowel disease-associated bone loss.

  20. K+ channel TASK-1 knockout mice show enhanced sensitivities to ataxic and hypnotic effects of GABA(A) receptor ligands.

    PubMed

    Linden, Anni-Maija; Aller, M Isabel; Leppä, Elli; Rosenberg, Per H; Wisden, William; Korpi, Esa R

    2008-10-01

    TASK two-pore-domain leak K(+) channels occur throughout the brain. However, TASK-1 and TASK-3 knockout (KO) mice have few neurological impairments and only mildly reduced sensitivities to inhalational anesthetics, contrasting with the anticipated functions and importance of these channels. TASK-1/-3 channel expression can compensate for the absence of GABA(A) receptors in GABA(A) alpha6 KO mice. To investigate the converse, we analyzed the behavior of TASK-1 and -3 KO mice after administering drugs with preferential efficacies at GABA(A) receptor subtypes: benzodiazepines (diazepam and flurazepam, active at alpha1betagamma2, alpha2betagamma2, alpha3betagamma2, and alpha5betagamma2 subtypes), zolpidem (alpha1betagamma2 subtype), propofol (beta2-3-containing receptors), gaboxadol (alpha4betadelta and alpha6betadelta subtypes), pregnanolone, and pentobarbital (many subtypes). TASK-1 KO mice showed increased motor impairment in rotarod and beam-walking tests after diazepam and flurazepam administration but not after zolpidem. They also showed prolonged loss of righting reflex induced by propofol and pentobarbital. Autoradiography indicated no change in GABA(A) receptor ligand binding levels. These altered behavioral responses to GABAergic drugs suggest functional up-regulation of alpha2beta2/3gamma2 and alpha3beta2/3gamma2 receptor subtypes in TASK-1 KO mice. In addition, female, but not male, TASK-1 KO mice were more sensitive to gaboxadol, suggesting an increased influence of alpha4betadelta or alpha6betadelta subtypes. The benzodiazepine sensitivity of TASK-3 KO mice was marginally increased. Our results underline that TASK-1 channels perform such key functions in the brain that compensation is needed for their absence. Furthermore, because inhalation anesthetics act partially through GABA(A) receptors, the up-regulation of GABA(A) receptor function in TASK-1 KO mice might mask TASK-1 channel's significance as a target for inhalation anesthetics.

  1. Parturition failure in mice lacking Mamld1

    PubMed Central

    Miyado, Mami; Miyado, Kenji; Katsumi, Momori; Saito, Kazuki; Nakamura, Akihiro; Shihara, Daizou; Ogata, Tsutomu; Fukami, Maki

    2015-01-01

    In mice, the onset of parturition is triggered by a rapid decline in circulating progesterone. Progesterone withdrawal occurs as a result of functional luteolysis, which is characterized by an increase in the enzymatic activity of 20α-hydroxysteroid dehydrogenase (20α-HSD) in the corpus luteum and is mediated by the prostaglandin F2α (PGF2α) signaling. Here, we report that the genetic knockout (KO) of Mamld1, which encodes a putative non-DNA-binding regulator of testicular steroidogenesis, caused defective functional luteolysis and subsequent parturition failure and neonatal deaths. Progesterone receptor inhibition induced the onset of parturition in pregnant KO mice, and MAMLD1 regulated the expression of Akr1c18, the gene encoding 20α-HSD, in cultured cells. Ovaries of KO mice at late gestation were morphologically unremarkable; however, Akr1c18 expression was reduced and expression of its suppressor Stat5b was markedly increased. Several other genes including Prlr, Cyp19a1, Oxtr, and Lgals3 were also dysregulated in the KO ovaries, whereas PGF2α signaling genes remained unaffected. These results highlight the role of MAMLD1 in labour initiation. MAMLD1 likely participates in functional luteolysis by regulating Stat5b and other genes, independent of the PGF2α signaling pathway. PMID:26435405

  2. DBI/ACBP loss-of-function does not affect anxiety-like behaviour but reduces anxiolytic responses to diazepam in mice.

    PubMed

    Budry, Lionel; Bouyakdan, Khalil; Tobin, Stephanie; Rodaros, Demetra; Marcher, Ann-Britt; Mandrup, Susanne; Fulton, Stephanie; Alquier, Thierry

    2016-10-15

    Diazepam is well known for its anxiolytic properties, which are mediated via activation of the GABAA receptor. Diazepam Binding Inhibitor (DBI), also called acyl-CoA binding protein (ACBP), is a ubiquitously expressed protein originally identified based on its ability to displace diazepam from its binding site on the GABAA receptor. Central administration of ACBP or its cleaved fragment, commonly referred to as endozepines, induces proconflict and anxiety-like behaviour in rodents. For this reason, ACBP is known as an anxiogenic peptide. However, the role of endogenous ACBP in anxiety-like behaviour and anxiolytic responses to diazepam has not been investigated. To address this question, we assessed anxiety behaviour and anxiolytic responses to diazepam in two complementary loss-of-function mouse models including astrocyte-specific ACBP KO (ACBP(GFAP) KO) and whole-body KO (ACBP KO) mice. Male and female ACBP(GFAP) KO and ACBP KO mice do not show significant changes in anxiety-like behaviour compared to control littermates during elevated plus maze (EPM) and open field (OF) tests. Surprisingly, ACBP(GFAP) KO and ACBP KO mice were unresponsive to the anxiolytic effect of a low dose of diazepam during EPM tests. In conclusion, our experiments using genetic ACBP loss-of-function models suggest that endozepines deficiency does not affect anxiety-like behaviour in mice and impairs the anxiolytic action of diazepam. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. The role of T1r3 and Trpm5 in carbohydrate-induced obesity in mice.

    PubMed

    Glendinning, John I; Gillman, Jennifer; Zamer, Haley; Margolskee, Robert F; Sclafani, Anthony

    2012-08-20

    We examined the role of T1r3 and Trpm5 taste signaling proteins in carbohydrate-induced overeating and obesity. T1r3, encoded by Tas1r3, is part of the T1r2+T1r3 sugar taste receptor, while Trpm5 mediates signaling for G protein-coupled receptors in taste cells. It is known that C57BL/6 wild-type (WT) mice are attracted to the tastes of both Polycose (a glucose polymer) and sucrose, whereas Tas1r3 KO mice are attracted to the taste of Polycose but not sucrose. In contrast, Trpm5 KO mice are not attracted to the taste of sucrose or Polycose. In Experiment 1, we maintained the WT, Tas1r3 KO and Trpm5 KO mice on one of three diets for 38days: lab chow plus water (Control diet); chow, water and 34% Polycose solution (Polycose diet); or chow, water and 34% sucrose solution (Sucrose diet). The WT and Tas1r3 KO mice overconsumed the Polycose diet and became obese. The WT and Tas1r3 KO mice also overconsumed the Sucrose diet, but only the WT mice became obese. The Trpm5 KO mice, in contrast, showed little or no overeating on the Sucrose and Polycose diets, and gained less weight than WT mice on these diets. In Experiment 2, we asked whether the Tas1r3 KO mice exhibited impaired weight gain on the Sucrose diet because it was insipid. To test this hypothesis, we maintained the WT and Tas1r3 KO mice on one of two diets for 38 days: chow, water and a dilute (1%) but highly palatable Intralipid emulsion (Control diet); or chow, water and a 34% sucrose+1% Intralipid solution (Suc+IL diet). The WT and Tas1r3 KO mice both exhibited little or no overeating but became obese on the Suc+IL diet. Our results suggest that nutritive solutions must be highly palatable to cause carbohydrate-induced obesity in mice, and that palatability produces this effect in part by enhancing nutrient utilization. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Knockout of arsenic (+3 oxidation state) methyltransferase is associated with adverse metabolic phenotype in mice: the role of sex and arsenic exposure.

    PubMed

    Douillet, Christelle; Huang, Madelyn C; Saunders, R Jesse; Dover, Ellen N; Zhang, Chongben; Stýblo, Miroslav

    2017-07-01

    Susceptibility to toxic effects of inorganic arsenic (iAs) depends, in part, on efficiency of iAs methylation by arsenic (+3 oxidation state) methyltransferase (AS3MT). As3mt-knockout (KO) mice that cannot efficiently methylate iAs represent an ideal model to study the association between iAs metabolism and adverse effects of iAs exposure, including effects on metabolic phenotype. The present study compared measures of glucose metabolism, insulin resistance and obesity in male and female wild-type (WT) and As3mt-KO mice during a 24-week exposure to iAs in drinking water (0.1 or 1 mg As/L) and in control WT and As3mt-KO mice drinking deionized water. Results show that effects of iAs exposure on fasting blood glucose (FBG) and glucose tolerance in either WT or KO mice were relatively minor and varied during the exposure. The major effects were associated with As3mt KO. Both male and female control KO mice had higher body mass with higher percentage of fat than their respective WT controls. However, only male KO mice were insulin resistant as indicated by high FBG, and high plasma insulin at fasting state and 15 min after glucose challenge. Exposure to iAs increased fat mass and insulin resistance in both male and female KO mice, but had no significant effects on body composition or insulin resistance in WT mice. These data suggest that As3mt KO is associated with an adverse metabolic phenotype that is characterized by obesity and insulin resistance, and that the extent of the impairment depends on sex and exposure to iAs, including exposure to iAs from mouse diet.

  5. Bisphosphonates Improve Trabecular Bone Mass and Normalize Cortical Thickness in Ovariectomized, Osteoblast Connexin43 Deficient Mice

    PubMed Central

    Watkins, Marcus P.; Norris, Jin Yi; Grimston, Susan K.; Zhang, Xiaowen; Phipps, Roger J.; Ebetino, Frank H.; Civitelli, Roberto

    2012-01-01

    The gap junction protein, connexin43 (Cx43) controls both bone formation and osteoclastogenesis via osteoblasts and/or osteocytes. Cx43 has also been proposed to mediate an anti-apoptotic effect of bisphosphonates, potent inhibitors of bone resorption. We studied whether bisphosphonates are effective in protecting mice with a conditional Cx43 gene deletion in osteoblasts and osteocytes (cKO) from the consequences of ovariectomy on bone mass and strength. Ovariectomy resulted in rapid loss of trabecular bone followed by a slight recovery in wild type (WT) mice, and a similar degree of trabecular bone loss, albeit slightly delayed, occurred in cKO mice. Treatment with either risedronate (20µg/kg) or alendronate (40µg/kg) prevented ovariectomy-induced bone loss in both genotypes. In basal conditions, bones of cKO mice have larger marrow area, higher endocortical osteoclast number, and lower cortical thickness and strength relative to WT. Ovariectomy increased endocortical osteoclast number in WT but not in cKO mice. Both bisphosphonates prevented these increases in WT mice, and normalized endocortical osteoclast number, cortical thickness and bone strength in cKO mice. Thus, lack of osteoblast/osteocyte Cx43 does not alter bisphosphonate action on bone mass and strength in estrogen deficiency. These results support the notion that one of the main functions of Cx43 in cortical bone is to restrain osteoblast and/or osteocytes from inducing osteoclastogenesis at the endocortical surface. PMID:22750450

  6. Thy1 is a positive regulator of osteoblast differentiation and modulates bone homeostasis in obese mice.

    PubMed

    Paine, Ananta; Woeller, Collynn F; Zhang, Hengwei; de la Luz Garcia-Hernandez, Maria; Huertas, Nelson; Xing, Lianping; Phipps, Richard P; Ritchlin, Christopher T

    2018-01-17

    Thy1 (CD90), a glycosylated, glycophosphatidylinositol-anchored membrane protein highly expressed by subsets of mesenchymal stem cells and fibroblasts, inhibits adipogenesis. The role of Thy1 on bone structure and function has been poorly studied and represents a major knowledge gap. Therefore, we analyzed the long bones of wild-type (WT) and Thy1 knockout (KO) mice with micro-computed tomography (CT) and histomorphometry to compare changes in bone architecture and overall bone structure. micro-CT analysis of long bones revealed Thy1 KO and WT mice fed a high-fat diet demonstrated bone structural parameters at 4 mo that differed significantly between WT and KO mice. A significant reduction in trabecular bone volume was noted in Thy1 KO mice. The most prominent differences were observed in trabecular bone volume ratio and trabecular bone connectivity density. Consistent with micro-CT measurements, histomorphometric analysis also showed decreased bone volume in the obese Thy1 KO mice compared to obese WT mice. In vitro assays revealed that osteogenic conditions increased Thy1 expression during OB differentiation and absence of Thy1 attenuated osteoblastogenesis. Together, these findings support the concept that Thy1 serves as a major mechanistic link to regulate bone formation and negatively regulate adipogenesis.-Paine, A., Woeller, C. F., Zhang, H., Garcia-Hernandez, M. L., Huertas, N., Xing, L., Phipps, R. P., Ritchlin, C. T. Thy1 is a positive regulator of osteoblast differentiation and modulates bone homeostasis in obese mice.

  7. Effects of loss of steroid receptor coactivator-1 on the skeletal response to estrogen in mice.

    PubMed

    Mödder, Ulrike I L; Sanyal, Arunik; Kearns, Ann E; Sibonga, Jean D; Nishihara, Eijun; Xu, Jianming; O'Malley, Bert W; Ritman, Erik L; Riggs, B Lawrence; Spelsberg, Thomas C; Khosla, Sundeep

    2004-02-01

    Steroid receptor coactivator (SRC)-1 is an important nuclear receptor coactivator that enhances estrogen (E) action in many tissues, but its role in mediating E effects on bone is unknown. Thus, we assessed the skeletal response to ovariectomy (ovx) and E replacement in SRC-1 knockout (KO) mice compared with wild-type (WT) littermates. Bone mineral density was measured by dual-energy x-ray absorptiometry and peripheral quantitative computed tomography at baseline and after 2 months of sham surgery, ovx, or ovx plus E replacement. Microcomputed tomography and bone histomorphometry were also performed at the end of the study. Both WT and SRC-1 KO mice lost bone at multiple sites after ovx; however, although an estradiol (E(2)) dose of 10 microg/kg.d completely prevented loss of cancellous bone (at the lumbar spine and tibial metaphysis) in the WT mice, it was entirely ineffective in preventing cancellous bone loss at these sites in the SRC-1 KO mice. This E(2) dose was, however, equally effective on cortical bone in the tibia in the SRC-1 KO and WT mice. Moreover, a 4-fold higher dose of E(2) was able to overcome the deficit in E action in cancellous bone in the SRC-1 KO mice. These findings establish that, in mice, loss of SRC-1 leads to skeletal resistance to E predominantly in cancellous bone.

  8. Environmental enrichment induces behavioural disturbances in neuropeptide Y knockout mice

    PubMed Central

    Reichmann, Florian; Wegerer, Vanessa; Jain, Piyush; Mayerhofer, Raphaela; Hassan, Ahmed M.; Fröhlich, Esther E.; Bock, Elisabeth; Pritz, Elisabeth; Herzog, Herbert; Holzer, Peter; Leitinger, Gerd

    2016-01-01

    Environmental enrichment (EE) refers to the provision of a complex and stimulating housing condition which improves well-being, behaviour and brain function of laboratory animals. The mechanisms behind these beneficial effects of EE are only partially understood. In the current report, we describe a link between EE and neuropeptide Y (NPY), based on findings from NPY knockout (KO) mice exposed to EE. Relative to EE-housed wildtype (WT) animals, NPY KO mice displayed altered behaviour as well as molecular and morphological changes in amygdala and hippocampus. Exposure of WT mice to EE reduced anxiety and decreased central glucocorticoid receptor expression, effects which were absent in NPY KO mice. In addition, NPY deletion altered the preference of EE items, and EE-housed NPY KO mice responded to stress with exaggerated hyperthermia, displayed impaired spatial memory, had higher hippocampal brain-derived neurotrophic factor mRNA levels and altered hippocampal synaptic plasticity, effects which were not seen in WT mice. Accordingly, these findings suggest that NPY contributes to the anxiolytic effect of EE and that NPY deletion reverses the beneficial effects of EE into a negative experience. The NPY system could thus be a target for “enviromimetics”, therapeutics which reproduce the beneficial effects of enhanced environmental stimulation. PMID:27305846

  9. Altered Immune Cytokine Expression Associated with KoRV B Infection and Season in Captive Koalas

    PubMed Central

    Higgins, Damien P.

    2016-01-01

    Koala (Phascolarctos cinereus) populations are increasingly vulnerable and one of the main threats is chlamydial infection. Koala retrovirus (KoRV) has been proposed as an underlying cause of the koala’s susceptibility to infection with Chlamydia and high rates of lymphoid neoplasia; however, the regionally ubiquitous, endogenous nature of this virus suggests that KoRV A infection is not sufficient for immune suppression to occur. A recently discovered exogenous variant of KoRV, KoRV B, has several structural elements that cause increased pathogenicity in related retroviruses and was associated with lymphoid neoplasia in one study. The present study assesses whether KoRV B infection is associated with alterations in immune function. Cytokine gene expression by mitogen stimulated lymphocytes of KoRV B positive (n = 5–6) and negative (n = 6–7) captive koalas was evaluated by qPCR four times (April 2014-February 2015) to control for seasonal variation. Key immune genes in the Th1 pathway (IFNγ, TNFα), Th2 pathway (IL 10, IL4, IL6) and Th17 pathway (IL17A), along with CD4:CD8 ratio, were assessed. KoRV B positive koalas showed significantly increased up-regulation of IL17A and IL10 in three out of four sampling periods and IFNγ, IL6, IL4 and TNFα in two out of four. IL17A is an immune marker for chlamydial pathogenesis in the koala; increased expression of IL17A in KoRV B positive koalas, and concurrent immune dysregulation, may explain the differences in susceptibility to chlamydial infection and severity of disease seen between individuals and populations. There was also marked seasonal variation in up-regulation for most of the cytokines and the CD4:CD8 ratio. The up-regulation in both Th1 and Th2 cytokines mirrors changes associated with immune dysregulation in humans and felids as a result of retroviral infections. This is the first report of altered immune expression in koalas infected by an exogenous variant of KoRV and also the first report of

  10. Altered Immune Cytokine Expression Associated with KoRV B Infection and Season in Captive Koalas.

    PubMed

    Maher, Iona E; Higgins, Damien P

    2016-01-01

    Koala (Phascolarctos cinereus) populations are increasingly vulnerable and one of the main threats is chlamydial infection. Koala retrovirus (KoRV) has been proposed as an underlying cause of the koala's susceptibility to infection with Chlamydia and high rates of lymphoid neoplasia; however, the regionally ubiquitous, endogenous nature of this virus suggests that KoRV A infection is not sufficient for immune suppression to occur. A recently discovered exogenous variant of KoRV, KoRV B, has several structural elements that cause increased pathogenicity in related retroviruses and was associated with lymphoid neoplasia in one study. The present study assesses whether KoRV B infection is associated with alterations in immune function. Cytokine gene expression by mitogen stimulated lymphocytes of KoRV B positive (n = 5-6) and negative (n = 6-7) captive koalas was evaluated by qPCR four times (April 2014-February 2015) to control for seasonal variation. Key immune genes in the Th1 pathway (IFNγ, TNFα), Th2 pathway (IL 10, IL4, IL6) and Th17 pathway (IL17A), along with CD4:CD8 ratio, were assessed. KoRV B positive koalas showed significantly increased up-regulation of IL17A and IL10 in three out of four sampling periods and IFNγ, IL6, IL4 and TNFα in two out of four. IL17A is an immune marker for chlamydial pathogenesis in the koala; increased expression of IL17A in KoRV B positive koalas, and concurrent immune dysregulation, may explain the differences in susceptibility to chlamydial infection and severity of disease seen between individuals and populations. There was also marked seasonal variation in up-regulation for most of the cytokines and the CD4:CD8 ratio. The up-regulation in both Th1 and Th2 cytokines mirrors changes associated with immune dysregulation in humans and felids as a result of retroviral infections. This is the first report of altered immune expression in koalas infected by an exogenous variant of KoRV and also the first report of seasonal

  11. M3 muscarinic acetylcholine receptor plays a critical role in parasympathetic control of salivation in mice

    PubMed Central

    Nakamura, Takeshi; Matsui, Minoru; Uchida, Keiko; Futatsugi, Akira; Kusakawa, Shinji; Matsumoto, Nagisa; Nakamura, Kyoko; Manabe, Toshiya; Taketo, Makoto M; Mikoshiba, Katsuhiko

    2004-01-01

    The M1 and M3 subtypes are the major muscarinic acetylcholine receptors in the salivary gland and M3 is reported to be more abundant. However, despite initial reports of salivation abnormalities in M3-knockout (M3KO) mice, it is still unclear which subtype is functionally relevant in physiological salivation. In the present study, salivary secretory function was examined using mice lacking specific subtype(s) of muscarinic receptor. The carbachol-induced [Ca2+]i increase was markedly impaired in submandibular gland cells from M3KO mice and completely absent in those from M1/M3KO mice. This demonstrates that M3 and M1 play major and minor roles, respectively, in the cholinergically induced [Ca2+]i increase. Two-dimensional Ca2+-imaging analysis revealed the patchy distribution of M1 in submandibular gland acini, in contrast to the ubiquitous distribution of M3. In vivo administration of a high dose of pilocarpine (10 mg kg−1, s.c.) to M3KO mice caused salivation comparable to that in wild-type mice, while no salivation was induced in M1/M3KO mice, indicating that salivation in M3KO mice is caused by an M1-mediated [Ca2+]i increase. In contrast, a lower dose of pilocarpine (1 mg kg−1, s.c.) failed to induce salivation in M3KO mice, but induced abundant salivation in wild-type mice, indicating that M3-mediated salivation has a lower threshold than M1-mediated salivation. In addition, M3KO mice, but not M1KO mice, had difficulty in eating dry food, as shown by frequent drinking during feeding, suggesting that salivation during eating is mediated by M3 and that M1 plays no practical role in it. These results show that the M3 subtype is essential for parasympathetic control of salivation and a reasonable target for the drug treatment and gene therapy of xerostomia, including Sjögren's syndrome. PMID:15146045

  12. Deficiency in lysophosphatidylcholine acyltransferase 3 reduces plasma levels of lipids by reducing lipid absorption in mice.

    PubMed

    Li, Zhiqiang; Jiang, Hui; Ding, Tingbo; Lou, Caixia; Bui, Hai H; Kuo, Ming-Shang; Jiang, Xian-Cheng

    2015-11-01

    Phosphatidylcholines (PCs) are structural and functional constituents of cell membranes. The activity of acyltransferase (lysophosphatidylcholine acyltransferase [LPCAT]) is required for addition of polyunsaturated fatty acids to the sn-2 position of PCs and is therefore required to maintain cell membrane structure and function. LPCAT3 is the most abundant isoform of LPCAT in the small intestine and liver, which are important sites of plasma lipoprotein metabolism. We investigated the effects of Lpcat3 disruption on lipid metabolism in mice. We disrupted the gene Lpcat3 in C57BL/6J mice to create LPCAT3 knockout (KO) mice. Livers and small intestinal tissues were collected from LPCAT3 KO and C57BL/6J parental strain (controls), and levels of LPCAT messenger RNAs and protein were measured. Levels of lipids and lipoproteins were measured in plasma samples. We isolated enterocytes from mice and measured levels of RNAs and proteins involved in lipid uptake by real-time polymerase chain reaction and immunoblot assays, respectively. We assessed lipid absorption and PC subspecies in the enterocyte plasma membrane using liquid chromatography with tandem mass spectometry. LPCAT3 KO mice survived only 3 weeks after birth. Oil Red O staining showed that the control but not LPCAT3 KO mice accumulated lipids in the small intestine; levels of Niemann-Pick C1-like 1 (NPC1L1) and fatty acid transporter protein 4 (FATP4), which regulate lipid uptake, were greatly reduced in the small intestines of LPCAT3 KO mice. Oral administration of PC and olive oil allowed the LPCAT3 KO mice to survive with the same body weights as controls, but the KO mice had shorter and wider small-intestinal villi and longer and bigger small intestines. Plasma membranes of enterocytes from LPCAT3 KO mice also had significant reductions in the composition of polyunsaturated PCs and reduced levels of NPC1L1, CD36, and FATP4 proteins. These reductions were associated with reduced intestinal uptake of lipid by

  13. Podocyte-Specific GLUT4-Deficient Mice Have Fewer and Larger Podocytes and Are Protected From Diabetic Nephropathy

    PubMed Central

    Guzman, Johanna; Jauregui, Alexandra N.; Merscher-Gomez, Sandra; Maiguel, Dony; Muresan, Cristina; Mitrofanova, Alla; Diez-Sampedro, Ana; Szust, Joel; Yoo, Tae-Hyun; Villarreal, Rodrigo; Pedigo, Christopher; Molano, R. Damaris; Johnson, Kevin; Kahn, Barbara; Hartleben, Bjoern; Huber, Tobias B.; Saha, Jharna; Burke, George W.; Abel, E. Dale; Brosius, Frank C.; Fornoni, Alessia

    2014-01-01

    Podocytes are a major component of the glomerular filtration barrier, and their ability to sense insulin is essential to prevent proteinuria. Here we identify the insulin downstream effector GLUT4 as a key modulator of podocyte function in diabetic nephropathy (DN). Mice with a podocyte-specific deletion of GLUT4 (G4 KO) did not develop albuminuria despite having larger and fewer podocytes than wild-type (WT) mice. Glomeruli from G4 KO mice were protected from diabetes-induced hypertrophy, mesangial expansion, and albuminuria and failed to activate the mammalian target of rapamycin (mTOR) pathway. In order to investigate whether the protection observed in G4 KO mice was due to the failure to activate mTOR, we used three independent in vivo experiments. G4 KO mice did not develop lipopolysaccharide-induced albuminuria, which requires mTOR activation. On the contrary, G4 KO mice as well as WT mice treated with the mTOR inhibitor rapamycin developed worse adriamycin-induced nephropathy than WT mice, consistent with the fact that adriamycin toxicity is augmented by mTOR inhibition. In summary, GLUT4 deficiency in podocytes affects podocyte nutrient sensing, results in fewer and larger cells, and protects mice from the development of DN. This is the first evidence that podocyte hypertrophy concomitant with podocytopenia may be associated with protection from proteinuria. PMID:24101677

  14. Mice lacking NOX2 are hyperphagic and store fat preferentially in the liver.

    PubMed

    Costford, Sheila R; Castro-Alves, Jason; Chan, Kenny L; Bailey, Liane J; Woo, Minna; Belsham, Denise D; Brumell, John H; Klip, Amira

    2014-06-15

    Chronic low-grade inflammation is an important contributor to the development of insulin resistance, a hallmark of type 2 diabetes mellitus (T2DM). Obesity and high-fat feeding lead to infiltration of immune cells into metabolic tissues, promoting inflammation and insulin resistance. We hypothesized that macrophages from mice lacking NOX2 (Cybb), an essential component of the NADPH oxidase complex highly expressed in immune cells and associated with their inflammatory response, would be less inflammatory and that these mice would be protected from the development of high-fat-induced insulin resistance. Bone marrow-derived macrophages from NOX2 knockout (NOX2-KO) mice expressed lower levels of inflammatory markers (Nos2, Il6); however, NOX2-KO mice were hyperphagic and gained more weight than wild-type (WT) mice when fed either a chow or a high-fat (HF) diet. Surprisingly, NOX2-KO mice stored less lipid in epididymal white adipose tissue but more lipid in liver and had higher indexes of liver inflammation and macrophage infiltration than WT mice. Contrary to our hypothesis, HF-fed NOX2-KO mice were hyperinsulinemic and more insulin resistant than HF-fed WT mice, likely as a result of their higher hepatic steatosis and inflammation. In summary, NOX2 depletion promoted hyperphagia, hepatic steatosis, and inflammation with either normal or high-fat feeding, exacerbating insulin resistance. We propose that NOX2 participates in food intake control and lipid distribution in mice. Copyright © 2014 the American Physiological Society.

  15. Immature morphological properties in subcellular-scale structures in the dentate gyrus of Schnurri-2 knockout mice: a model for schizophrenia and intellectual disability.

    PubMed

    Nakao, Akito; Miyazaki, Naoyuki; Ohira, Koji; Hagihara, Hideo; Takagi, Tsuyoshi; Usuda, Nobuteru; Ishii, Shunsuke; Murata, Kazuyoshi; Miyakawa, Tsuyoshi

    2017-12-12

    Accumulating evidence suggests that subcellular-scale structures such as dendritic spine and mitochondria may be involved in the pathogenesis/pathophysiology of schizophrenia and intellectual disability. Previously, we proposed mice lacking Schnurri-2 (Shn2; also called major histocompatibility complex [MHC]-binding protein 2 [MBP-2], or human immunodeficiency virus type I enhancer binding protein 2 [HIVEP2]) as a schizophrenia and intellectual disability model with mild chronic inflammation. In the mutants' brains, there are increases in C4b and C1q genes, which are considered to mediate synapse elimination during postnatal development. However, morphological properties of subcellular-scale structures such as dendritic spine in Shn2 knockout (KO) mice remain unknown. In this study, we conducted three-dimensional morphological analyses in subcellular-scale structures in dentate gyrus granule cells of Shn2 KO mice by serial block-face scanning electron microscopy. Shn2 KO mice showed immature dendritic spine morphology characterized by increases in spine length and decreases in spine diameter. There was a non-significant tendency toward decrease in spine density of Shn2 KO mice over wild-type mice, and spine volume was indistinguishable between genotypes. Shn2 KO mice exhibited a significant reduction in GluR1 expression and a nominally significant decrease in SV2 expression, while PSD95 expression had a non-significant tendency to decrease in Shn2 KO mice. There were significant decreases in dendrite diameter, nuclear volume, and the number of constricted mitochondria in the mutants. Additionally, neuronal density was elevated in Shn2 KO mice. These results suggest that Shn2 KO mice serve as a unique tool for investigating morphological abnormalities of subcellular-scale structures in schizophrenia, intellectual disability, and its related disorders.

  16. Inhibition of Nitric Oxide Synthase 1 Induces Salt-Sensitive Hypertension in Nitric Oxide Synthase 1α Knockout and Wild-Type Mice.

    PubMed

    Wang, Ximing; Chandrashekar, Kiran; Wang, Lei; Lai, En Yin; Wei, Jin; Zhang, Gensheng; Wang, Shaohui; Zhang, Jie; Juncos, Luis A; Liu, Ruisheng

    2016-04-01

    We recently showed that α, β, and γ splice variants of neuronal nitric oxide synthase (NOS1) expressed in the macula densa and NOS1β accounts for most of the NO generation. We have also demonstrated that the mice with deletion of NOS1 specifically from the macula densa developed salt-sensitive hypertension. However, the global NOS1 knockout (NOS1KO) strain is neither hypertensive nor salt sensitive. This global NOS1KO strain is actually an NOS1αKO model. Consequently, we hypothesized that inhibition of NOS1β in NOS1αKO mice induces salt-sensitive hypertension. NOS1αKO and C57BL/6 wild-type (WT) mice were implanted with telemetry transmitters and divided into 7-nitroindazole (10 mg/kg/d)-treated and nontreated groups. All of the mice were fed a normal salt (0.4% NaCl) diet for 5 days, followed by a high-salt diet (4% NaCl). NO generation by the macula densa was inhibited by >90% in WT and NOS1αKO mice treated with 7-nitroindazole. Glomerular filtration rate in conscious mice was increased by ≈ 40% after a high-salt diet in both NOS1αKO and WT mice. In response to acute volume expansion, glomerular filtration rate, diuretic and natriuretic response were significantly blunted in the WT and knockout mice treated with 7-nitroindazole. Mean arterial pressure had no significant changes in mice fed a high-salt diet, but increased ≈ 15 mm Hg similarly in NOS1αKO and WT mice treated with 7-nitroindazole. We conclude that NOS1β, but not NOS1α, plays an important role in control of sodium excretion and hemodynamics in response to either an acute or a chronic salt loading. © 2016 American Heart Association, Inc.

  17. Scavenger Receptor Class B Type 1 Deletion Led to Coronary Atherosclerosis and Ischemic Heart Disease in Low-density Lipoprotein Receptor Knockout Mice on Modified Western-type Diet.

    PubMed

    Liao, Jiawei; Guo, Xin; Wang, Mengyu; Dong, Chengyan; Gao, Mingming; Wang, Huan; Kayoumu, Abudurexiti; Shen, Qiang; Wang, Yuhui; Wang, Fan; Huang, Wei; Liu, George

    2017-02-01

    Atherosclerosis-prone apolipoprotein E (apoE) or low-density lipoprotein receptor (LDL-R) knockout (KO) mice are generally resistant to developing coronary atherosclerosis (CA) and ischemic heart disease (IHD). However, studies have demonstrated the occurrence of spontaneous CA and IHD in scavenger receptor class B type 1 (SR-BI)/apoE double KO (dKO) mice, which suggests that SR-BI could be a potential target for the prevention and therapy of CA and IHD. This possibility was later investigated in SR-BI/LDL-R dKO mice, but no signs of CA or IHD was identified when mice were fed a normal western-type diet. Here we explored whether SR-BI deletion could result in CA and IHD in LDL-R KO mice when fed a modified western-type diet containing higher (0.5%) cholesterol. Cardiac functions were detected by electrocardiography, single photon emission computed tomography (SPECT), echocardiography (Echo) and 2,3,5-triphenyltetrazolium chloride staining. CA was visualized by hematoxylin-eosin staining. After 12 weeks on the modified diet, SR-BI/LDL-R dKO mice developed cardiac ischemia/infarction, together with systolic dysfunction and left ventricular dilatation. CA was most severe at the aortic sinus level to an extent that no dKO mice survived to 20 weeks on the modified diet. None of control mice, however, developed CA or IHD. SR-BI deletion led to CA and IHD in LDL-R KO mice when fed the modified western-type diet. We established SR-BI/LDL-R dKO mice as a diet-induced murine model of human IHD and developed detection methods, using a combination of SPECT and Echo, for effective in vivo evaluation of cardiac functions.

  18. Scavenger Receptor Class B Type 1 Deletion Led to Coronary Atherosclerosis and Ischemic Heart Disease in Low-density Lipoprotein Receptor Knockout Mice on Modified Western-type Diet

    PubMed Central

    Liao, Jiawei; Guo, Xin; Wang, Mengyu; Dong, Chengyan; Gao, Mingming; Wang, Huan; Kayoumu, Abudurexiti; Shen, Qiang; Wang, Yuhui; Wang, Fan; Liu, George

    2017-01-01

    Aim: Atherosclerosis-prone apolipoprotein E (apoE) or low-density lipoprotein receptor (LDL-R) knockout (KO) mice are generally resistant to developing coronary atherosclerosis (CA) and ischemic heart disease (IHD). However, studies have demonstrated the occurrence of spontaneous CA and IHD in scavenger receptor class B type 1 (SR-BI)/apoE double KO (dKO) mice, which suggests that SR-BI could be a potential target for the prevention and therapy of CA and IHD. This possibility was later investigated in SR-BI/LDL-R dKO mice, but no signs of CA or IHD was identified when mice were fed a normal western-type diet. Here we explored whether SR-BI deletion could result in CA and IHD in LDL-R KO mice when fed a modified western-type diet containing higher (0.5%) cholesterol. Methods: Cardiac functions were detected by electrocardiography, single photon emission computed tomography (SPECT), echocardiography (Echo) and 2,3,5-triphenyltetrazolium chloride staining. CA was visualized by hematoxylin-eosin staining. Results: After 12 weeks on the modified diet, SR-BI/LDL-R dKO mice developed cardiac ischemia/infarction, together with systolic dysfunction and left ventricular dilatation. CA was most severe at the aortic sinus level to an extent that no dKO mice survived to 20 weeks on the modified diet. None of control mice, however, developed CA or IHD. Conclusions: SR-BI deletion led to CA and IHD in LDL-R KO mice when fed the modified western-type diet. We established SR-BI/LDL-R dKO mice as a diet-induced murine model of human IHD and developed detection methods, using a combination of SPECT and Echo, for effective in vivo evaluation of cardiac functions. PMID:27373983

  19. Effect of arylformamidase (kynurenine formamidase) gene inactivation in mice on enzymatic activity, kynurenine pathway metabolites and phenotype.

    PubMed

    Dobrovolsky, Vasily N; Bowyer, John F; Pabarcus, Michael K; Heflich, Robert H; Williams, Lee D; Doerge, Daniel R; Arvidsson, Björn; Bergquist, Jonas; Casida, John E

    2005-06-20

    The gene coding for arylformamidase (Afmid, also known as kynurenine formamidase) was inactivated in mice through the removal of a shared bidirectional promoter region regulating expression of the Afmid and thymidine kinase (Tk) genes. Afmid/Tk -deficient mice are known to develop sclerosis of glomeruli and to have an abnormal immune system. Afmid-catalyzed hydrolysis of N-formyl-kynurenine is a key step in tryptophan metabolism and biosynthesis of kynurenine-derived products including kynurenic acid, quinolinic acid, nicotinamide, NAD, and NADP. A disruption of these pathways is implicated in neurotoxicity and immunotoxicity. In wild-type (WT) mice, Afmid-specific activity (as measured by formyl-kynurenine hydrolysis) was 2-fold higher in the liver than in the kidney. Formyl-kynurenine hydrolysis was reduced by approximately 50% in mice heterozygous (HZ) for Afmid/Tk and almost completely eliminated in Afmid/Tk knockout (KO) mice. However, there was 13% residual formyl-kynurenine hydrolysis in the kidney of KO mice, suggesting the existence of a formamidase other than Afmid. Liver and kidney levels of nicotinamide plus NAD/NADP remained the same in WT, HZ and KO mice. Plasma concentrations of formyl-kynurenine, kynurenine, and kynurenic acid were elevated in KO mice (but not HZ mice) relative to WT mice, further suggesting that there must be enzymes other than Afmid (possibly in the kidney) capable of metabolizing formyl-kynurenine into kynurenine. Gradual kidney deterioration and subsequent failure in KO mice is consistent with high levels of tissue-specific Afmid expression in the kidney of WT but not KO mice. On this basis, the most significant function of the kynurenine pathway and Afmid in mice may be in eliminating toxic metabolites and to a lesser extent in providing intermediates for other processes.

  20. Gender differences in hypoxic acclimatization in cyclooxygenase-2-deficient mice.

    PubMed

    Xu, Kui; Sun, Xiaoyan; Benderro, Girriso F; Tsipis, Constantinos P; LaManna, Joseph C

    2017-02-01

    The aim of this study was to determine the effect of cyclooxygenase-2 (COX-2) gene deletion on the adaptive responses during prolonged moderate hypobaric hypoxia. Wild-type (WT) and COX-2 knockout (KO) mice of both genders (3 months old) were exposed to hypobaric hypoxia (~0.4 ATM) or normoxia for 21 days and brain capillary densities were determined. Hematocrit was measured at different time intervals; brain hypoxia-inducible factor -1 α (HIF-1 α ), angiopoietin 2 (Ang-2), brain erythropoietin (EPO), and kidney EPO were measured under normoxic and hypoxic conditions. There were no gender differences in hypoxic acclimatization in the WT mice and similar adaptive responses were observed in the female KO mice. However, the male KO mice exhibited progressive vulnerability to prolonged hypoxia. Compared to the WT and female KO mice, the male COX-2 KO mice had significantly lower survival rate and decreased erythropoietic and polycythemic responses, diminished cerebral angiogenesis, decreased brain accumulation of HIF-1 α , and attenuated upregulation of VEGF, EPO, and Ang-2 during hypoxia. Our data suggest that there are physiologically important gender differences in hypoxic acclimatization in COX-2-deficient mice. The COX-2 signaling pathway appears to be required for acclimatization in oxygen-limiting environments only in males, whereas female COX-2-deficient mice may be able to access COX-2-independent mechanisms to achieve hypoxic acclimatization. © 2017 Case Western Reserve University. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  1. Overview of the KoRIA Facility for Rare Isotope Beams

    NASA Astrophysics Data System (ADS)

    Ahn, Jung Keun; Bak, Sang In; Blumenfeld, Yorick; Chai, Jong-Seo; Cheon, Byung-Gu; Cheoun, Myung-Ki; Cho, Donghyun; Cho, Yong Sub; Choi, Bong Hyuk; Choi, Chang Ill; Choi, Eun Mi; Choi, Hyo Jung; Choi, Min Sik; Choi, Seonho; Choi, Tae Keun; Choi, Yeon Suk; Chung, Kie Hyung; Ha, Eun Ja; Ha, Jang Ho; Hahn, In Sik; Han, Jae Min; Han, Jang Min; Hong, Byungsik; Hong, Seung-Woo; Hong, Wan; Hwang, Sang Hoon; Hyun, Chang Ho; Jang, Doh Yun; Jang, Jaeho; Jeon, Dong-o.; Jeong, Doo; Jeong, Sun-Chan; Jhang, Genie; Joo, Eunah; Kadi, Yacine; Kang, Byoung Hwi; Kang, Hoon Su; Kim, Aram; Kim, Do Yoon; Kim, Dong Lak; Kim, Dong Uk; Kim, Eun Joo; Kim, Gi Dong; Kim, Hyun-Chul; Kim, In Gyu; Kim, Jong Tae; Kim, Jong Won; Kim, Joon Kon; Kim, Sang-Ho; Kim, Sang-hoon; Kim, Sung Hyun; Kim, Wooyoung; Kim, Yong Kyun; Ko, Seung Kook; Kwon, Myeun; Kwon, Young Kwan; Lee, Bo Young; Lee, Byoung Noh; Lee, Chang Hwan; Lee, Cheol Woo; Lee, Chun Sik; Lee, Kyong Sei; Lee, Hee Jung; Lee, Hee-Seock; Lee, Hyo Sang; Lee, Ju Hahn; Lee, Kang Ok; Lee, Kang Seog; Lee, Sang Duk; Lee, Seok Kwan; Lee, Su Houng; Lee, Young Sung; Lee, Young-Ouk; Lee, Yong Yung; Manchanda, Vijay K.; Moon, Chang Bum; Nam, Seung-il; Namkung, Won; Nolen, Jerry A.; Oh, Byung Hoon; Oh, Jin Hwan; Oh, Yongseok; Park, Byung Yoon; Park, Jin Ah; Park, Jin Yong; Park, Ki Hyeon; Park, Se Hwan; Park, Tae-Sun; Park, Woo-Yoon; Ryu, Chung Yeol; Ryu, Min Sang; Ryu, Sun Young; Sakai, Hideyuki; Seo, Hee Jeong; Shin, Jae Won; Shin, Seung Wook; Sigg, Peter; Sim, Kwang Souk; So, Woon Young; Song, Ho Seung; Song, Tae Yung; Suh, Byoung Jin; Tenreiro, Claudio; Tong, Zhou; Tribble, Robert E.; Woo, Hyung Ju; Yano, Yasushige; Yang, Hae-Ryong; Yang, Young Ku; Yeon, Yeong Heum; Yi, Won Ju; Yu, Byung Geel; Yu, Dai Hyuk; Yoo, In-Kwon; Yu, Seon Young; Yun, Chong Cheoul

    2013-03-01

    The Korea Rare Isotope Accelerator, currently referred to as KoRIA, is briefly presented. The KoRIA facility is aimed to enable cutting-edge sciences in a wide range of fields. It consists of a 70 kW isotope separator on-line (ISOL) facility driven by a 70 MeV, 1 mA proton cyclotron and a 400 kW in-flight fragmentation (IFF) facility. The ISOL facility uses a superconducting (SC) linac for post-acceleration of rare isotopes up to about 18 MeV/u, while the SC linac of IFF facility is capable of accelerating uranium beams up to 200 MeV/u, 8 pμA and proton beams up to 600 MeV, 660 μA. Overall features of the KoRIA facility are presented with a focus on the accelerator design.

  2. DISTINCT BEHAVIORAL PHENOTYPES IN MALE MICE LACKING THE THYROID HORMONE RECEPTOR α1 OR β ISOFORMS

    PubMed Central

    Vasudevan, Nandini; Morgan, Maria; Pfaff, Donald; Ogawa, Sonoko

    2013-01-01

    Thyroid hormones influence both neuronal development and anxiety via the thyroid hormone receptors (TRs). The TRs are encoded by two different genes, TRα and TRβ. The loss of TRα1 is implicated in increased anxiety in males, possibly via a hippocampal increase in GABAergic activity. We compared both social behaviors and two underlying and related non-social behaviors, state anxiety and responses to acoustic and tactile startle in the gonadally intact TRα1 knockout (α1KO) and TRβ (βKO) male mice to their wild-type counterparts. For the first time, we show an opposing effect of the two TR isoforms, TRα1 and TRβ, in the regulation of state anxiety, with α1 knockout animals (α1KO) showing higher levels of anxiety and βKO males showing less anxiety compared to respective wild-type mice. At odds with the increased anxiety in non-social environments, α1KO males also show lower levels of responsiveness to acoustic and tactile startle stimuli. Consistent with the data that T4 is inhibitory to lordosis in female mice, we show subtly increased sex behavior in α1KO male mice. These behaviors support the idea that TRα1 could be inhibitory to ERα driven transcription that ultimately impacts ERα driven behaviors such as lordosis. The behavioral phenotypes point to novel roles for the TRs, particularly in non-social behaviors such as state anxiety and startle. PMID:23567476

  3. Knockout Mice Reveal Key Roles for Claudin 18 in Alveolar Barrier Properties and Fluid Homeostasis

    PubMed Central

    Li, Guanglei; Flodby, Per; Luo, Jiao; Kage, Hidenori; Sipos, Arnold; Gao, Danping; Ji, Yanbin; Beard, LaMonta L.; Marconett, Crystal N.; DeMaio, Lucas; Kim, Yong Ho; Kim, Kwang-Jin; Laird-Offringa, Ite A.; Minoo, Parviz; Liebler, Janice M.; Zhou, Beiyun; Crandall, Edward D.

    2014-01-01

    Claudin proteins are major constituents of epithelial and endothelial tight junctions (TJs) that regulate paracellular permeability to ions and solutes. Claudin 18, a member of the large claudin family, is highly expressed in lung alveolar epithelium. To elucidate the role of claudin 18 in alveolar epithelial barrier function, we generated claudin 18 knockout (C18 KO) mice. C18 KO mice exhibited increased solute permeability and alveolar fluid clearance (AFC) compared with wild-type control mice. Increased AFC in C18 KO mice was associated with increased β-adrenergic receptor signaling together with activation of cystic fibrosis transmembrane conductance regulator, higher epithelial sodium channel, and Na-K-ATPase (Na pump) activity and increased Na-K-ATPase β1 subunit expression. Consistent with in vivo findings, C18 KO alveolar epithelial cell (AEC) monolayers exhibited lower transepithelial electrical resistance and increased solute and ion permeability with unchanged ion selectivity. Claudin 3 and claudin 4 expression was markedly increased in C18 KO mice, whereas claudin 5 expression was unchanged and occludin significantly decreased. Microarray analysis revealed changes in cytoskeleton-associated gene expression in C18 KO mice, consistent with observed F-actin cytoskeletal rearrangement in AEC monolayers. These findings demonstrate a crucial nonredundant role for claudin 18 in the regulation of alveolar epithelial TJ composition and permeability properties. Increased AFC in C18 KO mice identifies a role for claudin 18 in alveolar fluid homeostasis beyond its direct contributions to barrier properties that may, at least in part, compensate for increased permeability. PMID:24588076

  4. NRSF/REST neuronal deficient mice are more vulnerable to the neurotoxin MPTP.

    PubMed

    Yu, Mei; Suo, Haiyun; Liu, Ming; Cai, Lei; Liu, Jie; Huang, Yufang; Xu, Jing; Wang, Yancong; Zhu, Cuiqing; Fei, Jian; Huang, Fang

    2013-03-01

    Parkinson's disease (PD) is characterized by progressing loss of dopaminergic neurons in the midbrain. Abnormal gene expression plays a critical role in its pathogenesis. Neuron-restrictive silencer factor (NRSF)/neuronal repressor element-1 silencing transcription factor (REST), a member of the zinc finger transcription factors, inhibits the expression of neuron-specific genes in nonneuronal cells, and regulates neurogenesis. Our previous work showed that 1-methyl-4-phenyl-pyridinium ion triggers dynamic changes of messenger RNA and protein expression of NRSF in human dopaminergic SH-SY5Y cells, and alteration of NRSF expression exacerbates 1-methyl-4-phenyl-pyridinium ion-induced cell death. The purpose of this study was to explore the in vivo role of NRSF in the progress of PD by using NRSF/REST neuron-specific conditional knockout mice (cKO). 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was adopted to generate PD models in the cKO mice and wild type littermates. At 1, 3, 7, 14, 21, and 28 days after MPTP injection, behavioral tests were performed, and cKO mice displayed some impairments in locomotor activities. Also, the reduction of tyrosine hydroxylase protein in the striatum and the loss of dopaminergic neurons in the substantia nigra were more severe in the cKO mice. Meanwhile, the cKO mice exhibited a more dramatic depletion of striatal dopamine, accompanied by an increase in glial fibrillary acidic protein (GFAP) expression and sustained interleukin-1β transcription. These results suggested that NRSF/REST neuronal cKO mice are more vulnerable to the dopaminergic neurotoxin MPTP. Disturbance of the homeostasis of NRSF and its target genes, gliogenesis, and inflammation may contribute to the higher MPTP sensitivity in NRSF/REST neuronal cKO mice. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Oxytocin receptor knockout mice display deficits in the expression of autism-related behaviors

    PubMed Central

    Pobbe, Roger L.H.; Pearson, Brandon L.; Defensor, Erwin B.; Bolivar, Valerie J.; Young, W. Scott; Lee, Heon-Jin; Blanchard, D. Caroline; Blanchard, Robert J.

    2012-01-01

    A wealth of studies has implicated oxytocin (Oxt) and its receptors (Oxtr) in the mediation of social behaviors and social memory in rodents. It has been suggested that failures in this system contribute to deficits in social interaction that characterize autism spectrum disorders (ASD). In the current analyses, we investigated the expression of autism-related behaviors in mice that lack the ability to synthesize the oxytocin receptor itself, Oxtr knockout (KO) mice, as compared to their wild-type (WT) littermates. In the visible burrow system, Oxtr KO mice showed robust reductions in frontal approach, huddling, allo-grooming, and flight, with more time spent alone, and in self-grooming, as compared to WT. These results were corroborated in the three-chambered test: unlike WT, Oxtr KO mice failed to spend more time in the side of the test box containing an unfamiliar CD-1 mouse. In the social proximity test, Oxtr KO mice showed clear reductions in nose to nose and anogenital sniff behaviors oriented to an unfamiliar C57BL/6J (B6) mouse. In addition, our study revealed no differences between Oxtr WT and KO genotypes in the occurrence of motor and cognitive stereotyped behaviors. A significant genotype effect was found in the scent marking analysis, with Oxtr KO mice showing a decreased number of scent marks, as compared to WT. Overall, the present data indicate that the profile for Oxtr KO mice, including consistent social deficits, and reduced levels of communication, models multiple components of the ASD phenotype. This article is part of a Special Issue entitled Oxytocin, Vasopressin, and Social Behavior. PMID:22100185

  6. Intestinal Vitamin D Receptor is Required for Normal Calcium and Bone Metabolism in Mice

    PubMed Central

    Xue, Yingben; Fleet, James C.

    2009-01-01

    Background & Aims Vitamin D Receptor (VDR)-knockout mice develop severe hypocalcaemia and rickets, accompanied by disruption of active intestinal calcium absorption. To specifically study the effects of VDR in intestinal Ca absorption, we investigated whether restoration of intestinal VDR is sufficient to recover the phenotype of VDR-knockout mice. Methods We generated mice with intestine-specific transgenic expression of human VDR and crossed them to VDR knockout mice. The intestine, kidney and bone phenotypes of the VDR-knockout mice with intestine-specific expression of human VDR (KO/TG) were analyzed. Results Transgenic expression of VDR in the intestine of VDR-knockout mice normalized duodenal vitamin D-regulated calcium absorption as well as vitamin D-regulated calbindin D9k and TRPV6 gene expression in the duodenum and proximal colon. As a result, animal growth and the serum levels of calcium and parathyroid hormone were normalized in KO/TG mice. Other phenotypes were revealed when calcium metabolism was normalized in KO/TG mice: serum 1,25 dihydroxyvitamin D levels were higher in KO/TG mice than normal mice, due to reduced renal expression of the vitamin D-degrading enzyme CYP24; urinary calcium excretion was higher and associated with lower renal calbindin D9k and D28k than normal mice; and bone density and volume increased in KO/TG compared with normal mice, due to increased mineral apposition rate and osteoblast number. Conclusions Intestinal VDR and vitamin D-regulated intestinal calcium absorption are critical for controlling whole-body calcium metabolism in growing mice. Normalizing intestinal calcium absorption and metabolism reveals essential roles for VDR in control of bone formation, renal control of serum 1,25(OH)2D and urinary calcium excretion. PMID:19254681

  7. [Role of LIGHT signal pathway in Chlamydia muridarum urogenital infection in mice].

    PubMed

    Chen, Lili; Sun, Yuanbin; Xu, Sha; Fu, Xizong; Zhou, Zhou; Lu, Chunxue; Yang, Fei; Xu, Guilian; Wu, Yimou

    2015-04-04

    To study the role of lymphotoxin-like inducible protein that competes with glycoprotein D for herpesvirus entry on T cells (LIGHT) in the development of protective immunity and pathology during Chlamydia Muridarum urogenital infection in mice. C57BL/6J wild type (wt) and mice deficient in LIGHT (LIGHT KO) were inoculated intravaginally with 1 x 10(4) IFUs of live C. muridarum organisms. Half mice of each group were reinfected on day 49 after primary infection. We took mice vaginal swabs every 3 or 4 days to monitor live organism shedding. On day 80 after the primary infection, mice were sacrificed, the vaginal tract was isolated for pathology analysis. The spleen cells were collected and IL-4, IL-5, IL-17 and IFN-y were detected by ELISA in the spleen cells culture supernatant after restimulated by UV-MoPn EB. The titers of different Ab isotypes were measured in mice serum by Indirect Immunofluorescence Assay. The chlamydia shedding time of LIGHT KO mice was similar to wild type mice, which cleared the organisms within 28 days after primary infection, and acquired protective immunity against C. muridarum reinfection. All mice regardless of genotypes developed severe upper genital tract pathology and showed no significant difference between LIGHT KO and wild type mice. All mice developed robust anti-C. muridarum organism IgG antibody responses and the ratios of IgG2a versus IgG1 showed no significant difference between LIGHT KO and wild type mice. Splenocytes from MoPn-infected LIGHT KO and wild type mice produced high levels of IFN-gamma and IL-17, but IL-4 and IL-5 couldn't be detected. LIGHT signal pathway may not correlated with protection against C. muridarum urogenital tract infection and urogenital tract pathology induced by C. muridarum.

  8. Severe systemic toxicity and urinary bladder cytotoxicity and regenerative hyperplasia induced by arsenite in arsenic (+ 3 oxidation state) methyltransferase knockout mice. A preliminary report

    SciTech Connect

    Yokohira, Masanao; Arnold, Lora L.; Pennington, Karen L.

    2010-07-15

    Arsenic (+ 3 oxidation state) methyltransferase (As3mt) catalyzes reactions which convert inorganic arsenic to methylated metabolites. This study determined whether the As3mt null genotype in the mouse modifies cytotoxic and proliferative effects seen in urinary bladders of wild type mice after exposure to inorganic arsenic. Female wild type C57BL/6 mice and As3mt KO mice were divided into 3 groups each (n = 8) with free access to a diet containing 0, 100 or 150 ppm of arsenic as arsenite (As{sup III}). During the first week of As{sup III} exposure, As3mt KO mice exhibited severe and lethal systemic toxicity. At termination,more » urinary bladders of both As3mt KO and wild type mice showed hyperplasia by light microscopy. As expected, arsenic-containing granules were found in the superficial urothelial layer of wild type mice. In As3mt KO mice these granules were present in all layers of the bladder epithelium and were more abundant and larger than in wild type mice. Scanning electron microscopy of the bladder urothelium of As3mt KO mice treated with 100 ppm As{sup III} showed extensive superficial necrosis and hyperplastic changes. In As3mt KO mice, livers showed severe acute inflammatory changes and spleen size and lymphoid areas were decreased compared with wild type mice. Thus, diminished arsenic methylation in As3mt KO mice exacerbates systemic toxicity and the effects of As{sup III} on the bladder epithelium, showing that altered kinetic and dynamic behavior of arsenic can affect its toxicity.« less

  9. Impact of chronic low to moderate alcohol consumption on blood lipid and heart energy profile in acetaldehyde dehydrogenase 2-deficient mice.

    PubMed

    Fan, Fan; Cao, Quan; Wang, Cong; Ma, Xin; Shen, Cheng; Liu, Xiang-wei; Bu, Li-ping; Zou, Yun-zeng; Hu, Kai; Sun, Ai-jun; Ge, Jun-bo

    2014-08-01

    To investigate the roles of acetaldehyde dehydrogenase 2 (ALDH2), the key enzyme of ethanol metabolism, in chronic low to moderate alcohol consumption-induced heart protective effects in mice. Twenty-one male wild-type (WT) or ALDH2-knockout (KO) mice were used in this study. In each genotype, 14 animals received alcohol (2.5%, 5% and 10% in week 1-3, respectively, and 18% in week 4-7), and 7 received water for 7 weeks. After the treatments, survival rate and general characteristics of the animals were evaluated. Serum ethanol and acetaldehyde levels and blood lipids were measured. Metabolomics was used to characterize the heart and serum metabolism profiles. Chronic alcohol intake decreased the survival rate of KO mice by 50%, and significantly decreased their body weight, but did not affect those of WT mice. Chronic alcohol intake significantly increased the serum ethanol levels in both WT and KO mice, but KO mice had significantly higher serum acetaldehyde levels than WT mice. Chronic alcohol intake significantly increased the serum HDL cholesterol levels in WT mice, and did not change the serum HDL cholesterol levels in KO mice. After chronic alcohol intake, WT and KO mice showed differential heart and serum metabolism profiles, including the 3 main energy substrate types (lipids, glucose and amino acids) and three carboxylic acid cycles. Low to moderate alcohol consumption increases HDL cholesterol levels and improves heart energy metabolism profile in WT mice but not in ALDH2-KO mice. Thus, preserved ALDH2 function is essential for the protective effect of low to moderate alcohol on the cardiovascular system.

  10. Chronic caffeine treatment protects against experimental autoimmune encephalomyelitis in mice: therapeutic window and receptor subtype mechanism.

    PubMed

    Wang, Tan; Xi, Na-na; Chen, Yu; Shang, Xiao-feng; Hu, Qiang; Chen, Jiang-fan; Zheng, Rong-yuan

    2014-11-01

    Chronic treatment with caffeine, the most widely consumed psychoactive drug and a non-selective antagonist of adenosine receptors, can protection against myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). In this study, we investigated the mechanism underlying caffeine-mediated neuroprotection against EAE by determining the effective therapeutic time-window of caffeine and the involvement of adenosine A2A and A1 receptor. We found that administration of caffeine during the effector phase (10 → 20 days post-immunization, d.p.i., corresponding to appearance of neurological deficits) but not the induction phase (0 → 10 d.p.i., before the appearance of ascending flaccid paralysis) significantly ameliorated EAE-induced neurobehavioral deficits, reduced the infiltration of inflammatory cells into the spinal cord and reduced the demyelination of spinal cord. Furthermore, genetic deletion of the A2AR exacerbated MOG-induced brain damage and caffeine administering to A2AR knockout mice reversed this EAE pathology by acting at non-A2AR target. The protective effect of chronic caffeine treatment was associated with up-regulation of brain A1R (but not A2AR). The identification of the effective therapeutic window of caffeine at the effector phase and clarification of non-A2AR target (likely A1R) in caffeine action in EAE models advance the therapeutic prospective that chronic caffeine consumption may attenuate brain damage in MS. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Learning-Induced Suboptimal Compensation for PKCι/λ Function in Mutant Mice.

    PubMed

    Sheng, Tao; Wang, Shaoli; Qian, Dandan; Gao, Jun; Ohno, Shigeo; Lu, Wei

    2017-06-01

    PKCι/λ has been proposed to be crucial in the early expression of long-term potentiation (LTP). Here, we further investigate the potential role of PKCι/λ in learning and memory by generating PKCι/λ conditional knockout mice specifically lacking PKCι/λ in the hippocampal CA1 pyramidal cells. Surprisingly, PKCι/λ cKO mice show normal hippocampal LTP and memory. Further close-up observation reveals compensation for PKCι/λ expression by PKMζ in PKCι/λ cKO mice. This compensation was not observed under basal conditions, but was detected either after LTP induction or learning-associated behavioral training. Accordingly, in the early stage of LTP expression, a switch from PKCι/λ- to PKMζ-dependent molecular mechanisms was detected in PKCι/λ cKO mice. Notably, when cKO mice were challenged with more difficult hippocampus-dependent learning tasks, moderate learning deficits were detected, suggesting a suboptimal compensation for PKCι/λ's function in PKCι/λ cKO mice. Thus, under physiological conditions, PKCι/λ is essential for hippocampal early-LTP and long-term memory (LTM). © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. Attenuating GABA(A) receptor signaling in dopamine neurons selectively enhances reward learning and alters risk preference in mice.

    PubMed

    Parker, Jones G; Wanat, Matthew J; Soden, Marta E; Ahmad, Kinza; Zweifel, Larry S; Bamford, Nigel S; Palmiter, Richard D

    2011-11-23

    Phasic dopamine (DA) transmission encodes the value of reward-predictive stimuli and influences both learning and decision-making. Altered DA signaling is associated with psychiatric conditions characterized by risky choices such as pathological gambling. These observations highlight the importance of understanding how DA neuron activity is modulated. While excitatory drive onto DA neurons is critical for generating phasic DA responses, emerging evidence suggests that inhibitory signaling also modulates these responses. To address the functional importance of inhibitory signaling in DA neurons, we generated mice lacking the β3 subunit of the GABA(A) receptor specifically in DA neurons (β3-KO mice) and examined their behavior in tasks that assessed appetitive learning, aversive learning, and risk preference. DA neurons in midbrain slices from β3-KO mice exhibited attenuated GABA-evoked IPSCs. Furthermore, electrical stimulation of excitatory afferents to DA neurons elicited more DA release in the nucleus accumbens of β3-KO mice as measured by fast-scan cyclic voltammetry. β3-KO mice were more active than controls when given morphine, which correlated with potential compensatory upregulation of GABAergic tone onto DA neurons. β3-KO mice learned faster in two food-reinforced learning paradigms, but extinguished their learned behavior normally. Enhanced learning was specific for appetitive tasks, as aversive learning was unaffected in β3-KO mice. Finally, we found that β3-KO mice had enhanced risk preference in a probabilistic selection task that required mice to choose between a small certain reward and a larger uncertain reward. Collectively, these findings identify a selective role for GABA(A) signaling in DA neurons in appetitive learning and decision-making.

  13. Sex differences in the development of diabetes in mice with deleted wolframin (Wfs1) gene.

    PubMed

    Noormets, K; Kõks, S; Muldmaa, M; Mauring, L; Vasar, E; Tillmann, V

    2011-05-01

    Wolfram syndrome, caused by mutations in the wolframin (Wfs1) gene, is characterised by juvenile-onset diabetes mellitus, progressive optic atrophy, diabetes insipidus and deafness. Diabetes tend to start earlier in boys. This study investigated sex differences in longitudinal changes in blood glucose concentration (BGC) in wolframin-deficient mice (Wfs1KO) and compared their plasma proinsulin and insulin levels with those of wild-type (wt) mice. Non-fasting BGC was measured weekly in 42 (21 males) mice from both groups at nine weeks of age. An intraperitoneal glucose tolerance test (IPGTT) was conducted at the 30 (th) week and plasma insulin, c-peptide and proinsulin levels were measured at the 32 (nd) week. At the 32 (nd) week, Wfs1KO males had increased BGC compared to wt males (9.40±0.60 mmol/l vs. 7.91±0.20 mmol/l; p<0.05). The opposite tendency was seen in females. Both male and female Wfs1KO mice had impaired glucose tolerance on IPGTT. Wfs1KO males had significantly lower mean plasma insulin levels than wt males (57.78±1.80 ng/ml vs. 69.42±3.06 ng/ml; p<0.01) and Wfs1KO females (70.30±4.42 ng/ml; p<0.05). Wfs1KO males had a higher proinsulin/insulin ratio than wt males (0.09±0.02 vs. 0.05±0.01; p=0.05) and Wfs1KO females (0.04±0.01; p<0.05). Plasma c-peptide levels in males were lower in Wfs1KO males (mean 55.3±14.0 pg/ml vs. 112.7±21.9 pg/ml; p<0.05). Male Wfs1KO mice had a greater risk of developing diabetes than female Wfs1KO mice. Low plasma insulin concentration with an increased proinsulin/insulin ratio in Wfs1KO males indicates possible disturbances in converting proinsulin to insulin which in long-term may lead to insulin deficiency. Further investigation is needed to clarify the mechanism for the sex differences in the development of diabetes in Wolfram syndrome. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

  14. Ketogenic diet-induced extension of longevity in epileptic Kcna1-null mice is influenced by gender and age at treatment onset.

    PubMed

    Chun, Kyoung-Chul; Ma, Shun-Chieh; Oh, Hyoungil; Rho, Jong M; Kim, Do Young

    2018-02-01

    Sudden unexpected death in epilepsy (SUDEP) is a leading cause of premature mortality in patients with epilepsy, and has been linked to multiple risk factors, including gender and early age at seizure onset. Despite the lack of a targeted therapy for SUDEP, it has recently been shown that a high-fat, low carbohydrate ketogenic diet (KD) enhances longevity in the epileptic Kcna1-null (KO) mouse, a validated model of SUDEP. Here, we asked whether the KD-driven prolongation of lifespan in KO mice is dependent on sex and/or age at treatment onset. We found that as KO mice aged, their daily seizure frequency steadily increased, but had early demise by postnatal day (PD) 46.9±0.8. In KO mice started on the KD at PD30, longevity was extended to a mean of PD69.8±1.7, accompanied with improved seizure control. Interestingly, while seizure control on the KD was similar between male and female mice, KD-fed female KO mice survived longer than their male counterparts. Further, epileptic mice initiated on the KD at PD25 had longer lifespans compared to those placed on the KD starting at PD35. Collectively, these data further support the notion that the KD can retard disease progression and sudden death in KO mice, but that this beneficial action is influenced by gender and age at the start of treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Lack of collagen XV is protective after ischemic stroke in mice

    PubMed Central

    Dhungana, Hiramani; Huuskonen, Mikko T; Pihlajaniemi, Taina; Heljasvaara, Ritva; Vivien, Denis; Kanninen, Katja M; Malm, Tarja; Koistinaho, Jari; Lemarchant, Sighild

    2017-01-01

    Collagens are key structural components of basement membranes, providing a scaffold for other components or adhering cells. Collagens and collagen-derived active fragments contribute to biological activities such as cell growth, differentiation and migration. Here, we report that collagen XV knock-out (ColXV KO) mice are resistant to experimental ischemic stroke. Interestingly, the infarcts of ColXV KO mice were as small as those of wild-type (WT) mice thrombolysed with recombinant tissue plasminogen activator (rtPA), the actual treatment for ischemic stroke. Importantly, there were no differences in the architecture of cerebrovascular anatomy between WT and ColXV KO mice. We found a twofold increase of the most potent pro-angiogenic factor, type A vascular growth endothelial factor (VEGF-A) in the ipsilateral cortex of rtPA-treated ischemic WT mice compared with untreated ischemic and sham-operated counterparts. A similar increase of VEGF-A was also found in both rtPA and untreated ischemic ColXV KO mice compared with sham ColXV KO mice. Finally, we evidenced that the levels of ColXV were increased in the plasma of WT mice treated with rtPA compared with untreated ischemic counterparts. Altogether, this study indicates that the lack ColXV is protective after stroke and that the degradation of endothelial ColXV may contribute to the beneficial effect of rtPA after ischemic stroke. The neuroprotection observed in ColXV KO mice may be attributed to the increased VEGF-A production following stroke in the ischemic territory. PMID:28079884

  16. Female PAPP-A knockout mice are resistant to metabolic dysfunction induced by high-fat/high-sucrose feeding at middle age.

    PubMed

    Hill, Cristal M; Arum, Oge; Boparai, Ravneet K; Wang, Feiya; Fang, Yimin; Sun, Liou Y; Masternak, Michal M; Bartke, Andrzej

    2015-06-01

    Longevity and aging are influenced by common intracellular signals of the insulin/insulin-like growth factor (IGF)-1 pathway. Abnormally high levels of bioactive IGF-1 increase the development of various cancers and may contribute to metabolic diseases such as insulin resistance. Enhanced availability of IGF-1 is promoted by cleavage of IGF binding proteins (IGFBPs) by proteases, including the pregnancy-associated plasma protein-A (PAPPA). In vitro, PAPP-A is regulated by pro-inflammatory cytokines (PICs) such as interleukin (IL)-6 and tumor necrosis factor (TNF). Mice born with deficiency of the Papp-a gene (PAPP-A knockout (KO) mice) live ~30-40 % longer than their normal littermates and have decreased bioactive IGF-1 on standard diets. Our objective was to elucidate how the effects of high-fat, high-sucrose diet (HFHS) promote obesity, induce metabolic dysfunction, and alter systemic cytokine expression in PAPP-A KO and normal mice. PAPP-A KO mice fed HFHS diet for 10 weeks were more glucose tolerant and had enhanced insulin sensitivity compared to normal mice fed HFHS diet. PAPP-A KO mice fed HFHS diet had lower levels of pro-inflammatory cytokines (IL-2, IL-6, and TNF-α) compared to normal mice fed the same diet. However, anti-inflammatory cytokine levels (IL-4 and adiponectin) were higher in PAPP-A KO mice fed HFHS diet compared to normal mice fed HFHS. Circulating PAPP-A levels were elevated in normal mice fed an HFHS diet compared to normal mice fed a standard, low-fat, low-sucrose (LFLS) diet. Indirect calorimetry showed, at 10 weeks of feeding HFHS diet, significantly increased oxygen consumption (VO2) in PAPP-A KO mice fed HFHS diet compared to normal mice fed the same diet. Furthermore, respiratory quotient (RQ) was significantly lower in PAPP-A KO mice fed HFHS diet compared to normal (N) mice fed HFHS diet indicating PAPP-A KO mice fed HFHS diet are able to rely on fat as their primary source of energy more so than normal controls. We conclude that

  17. A Note on Ko-Type O-Ending Syllables in Old Japanese

    ERIC Educational Resources Information Center

    Unger, J. Marshall

    1975-01-01

    Further evidence is offered to support the argument that ko-type o-ending syllables may have been secondary in nature in Old Japanese. Pre-Old Japanese indicates the */uwa/ sequence was manifested as /uwe/ and /uwu/ endings of o-ending syllable verbs. (SCC)

  18. The KoWa model: metric relations in geometric optical illusions.

    PubMed

    Wawzyniak, B

    1994-10-01

    The KoWa model described here gives a parametric account of the geometric conditions for 6 optical illusions from which prediction of illusory qualities of the figures in perceptual judgements may be accomplished using selected stimulus dimensions. The model is designed to allow integration of visual information.

  19. Angiotensin-(1-7)/Mas axis modulates fear memory and extinction in mice.

    PubMed

    Lazaroni, Thiago Luiz do Nascimento; Bastos, Cristiane Perácio; Moraes, Márcio Flávio Dutra; Santos, Robson Souza; Pereira, Grace Schenatto

    2016-01-01

    Inappropriate defense-alerting reaction to fear is a common feature of neuropsychiatric diseases. Therefore, impairments in brain circuits, as well as in molecular pathways underlying the neurovegetative adjustments to fear may play an essential role on developing neuropsychiatric disorders. Here we tested the hypothesis that interfering with angiotensin-(1-7) [Ang-(1-7)]/Mas receptor axis homeostasis, which appears to be essential to arterial pressure control, would affect fear memory and extinction. Mas knockout (MasKO) mice, in FVB/N background, showed normal cued fear memory and extinction, but increased freezing in response to context. Next, as FVB/N has poor performance in contextual fear memory, we tested MasKO in mixed 129xC57BL/6 background. MasKO mice behaved similarly to wild-type (WT), but memory extinction was slower in contextual fear conditioning to a weak protocol (1CS/US). In addition, delayed extinction in MasKO mice was even more pronounced after a stronger protocol (3CS/US). We showed previously that Angiotensin II receptor AT1 antagonist, losantan, rescued object recognition memory deficit in MasKO mice. Here, losartan was also effective. Memory extinction was accelerated in MasKO mice after treatment with losartan. In conclusion, we showed for the first time that Ang-(1-7)/Mas axis may modulate fear memory extinction. Furthermore, we suggest MasKO mice as an animal model to study post-traumatic stress disorder (PTSD). Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Behavioral Characterization of β-Arrestin 1 Knockout Mice in Anxiety-Like and Alcohol Behaviors.

    PubMed

    Robins, Meridith T; Chiang, Terrance; Berry, Jennifer N; Ko, Mee Jung; Ha, Jiwon E; van Rijn, Richard M

    2018-01-01

    β-Arrestin 1 and 2 are highly expressed proteins involved in the desensitization of G protein-coupled receptor signaling which also regulate a variety of intracellular signaling pathways. Gene knockout (KO) studies suggest that the two isoforms are not homologous in their effects on baseline and drug-induced behavior; yet, the role of β-arrestin 1 in the central nervous system has been less investigated compared to β-arrestin 2. Here, we investigate how global β-arrestin 1 KO affects anxiety-like and alcohol-related behaviors in male and female C57BL/6 mice. We observed increased baseline locomotor activity in β-arrestin 1 KO animals compared with wild-type (WT) or heterozygous (HET) mice with a sex effect. KO male mice were less anxious in a light/dark transition test, although this effect may have been confounded by increased locomotor activity. No differences in sucrose intake were observed between genotypes or sexes. Female β-arrestin 1 KO mice consumed more 10% alcohol than HET females in a limited 4-h access, two-bottle choice, drinking-in-the-dark model. In a 20% alcohol binge-like access model, female KO animals consumed significantly more alcohol than HET and WT females. A significant sex effect was observed in both alcohol consumption models, with female mice consuming greater amounts of alcohol than males relative to body weight. Increased sensitivity to latency to loss of righting reflex (LORR) was observed in β-arrestin 1 KO mice although no differences were observed in duration of LORR. Overall, our efforts suggest that β-arrestin 1 may be protective against increased alcohol consumption in females and hyperactivity in both sexes.

  1. Antidepressant-like effect of venlafaxine is abolished in µ-opioid receptor knockout mice

    PubMed Central

    Ide, Soichiro; Fujiwara, Shunsuke; Fujiwara, Masayuki; Sora, Ichiro; Ikeda, Kazutaka; Minami, Masabumi; Uhl, George R.; Ishihara, Kumatoshi

    2011-01-01

    Although the opioid system is known to modulate depression-like behaviors, its role in the effects of antidepressants is not yet clear. We investigated the role of µ-opioid receptors (MOPs) in the effects of venlafaxine, a serotonin and norepinephrine reuptake inhibitor, in the forced swim test using MOP-knockout (KO) mice. Venlafaxine reduced immobility time in wildtype mice (C57BL/6J), but not in MOP-KO mice, although no significant effects were observed on locomotor activity. These results suggest that MOPs play an important role in the antidepressant-like effects of venlafaxine. PMID:20703010

  2. The AF-1 activation-function of ERα may be dispensable to mediate the effect of estradiol on endothelial NO production in mice

    PubMed Central

    Pendaries, C.; Darblade, B.; Rochaix, P.; Krust, A.; Chambon, P.; Korach, K. S.; Bayard, F.; Arnal, J.-F.

    2002-01-01

    Two isoforms of estrogen receptor (ER) have been described: ERα and ERβ. The initial gene targeting of ERα, consisting in the introduction of a Neo cassette in exon 1 [αERKO, hereafter called ERα-Neo KO (knockout)], was reported in 1993. More recently, another mouse deficient in ERα because of the deletion of exon 2 (ERαKO, hereafter called ERα-Δ2 KO) was generated. In ovariectomized ERα-wild-type mice, estradiol (E2) increases uterine weight and basal production of endothelial nitric oxide (NO). Both of these effects are abolished in ERα-Δ2 KO mice. In contrast, we show here that both of these effects of E2 are partially (uterine weight) or totally (endothelial NO production) preserved in ERα-Neo KO. We also confirm the presence of two ERα mRNA splice variants in uterus and aorta from ERα-Neo KO mice. One of them encodes a chimeric ERα protein (ERα55), partially deleted in the A/B domain, that was detected in both uterus and aorta by Western blot analysis. The other ERα mRNA splice variant codes for an isoform deleted for the A/B domain (ERα46), which was detected in uterus of ERα-Neo KO, and wild-type mice. This protein isoform was not detected in aorta. The identification of these two N-terminal modified isoforms in uterus, and at least one of them in aorta, probably explains the persistence of the E2 effects in ERα-Neo KO mice. Furthermore, ERα-Neo KO mice may help in the elucidation of the specific functions of full-length ERα (ERα66) and ERα46, both shown to be physiologically generated in vivo. PMID:11854517

  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. Evidence for the Role of Histamine H3 Receptor in Alcohol Consumption and Alcohol Reward in Mice

    PubMed Central

    Nuutinen, Saara; Lintunen, Minnamaija; Vanhanen, Jenni; Ojala, Tiia; Rozov, Stanislav; Panula, Pertti

    2011-01-01

    Recent research suggests that histamine H3 receptor (H3R) antagonism may diminish motivational aspects of alcohol dependence. We studied the role of H3Rs in alcohol-related behaviors using H3R knockout (KO) mice and ligands. H3R KO mice consumed less alcohol than wild-type (WT) mice in a two-bottle free-choice test and in a ‘drinking in the dark' model. H3R antagonist ciproxifan suppressed and H3R agonist immepip increased alcohol drinking in C57BL/6J mice. Impairment in reward mechanisms in H3R KO mice was confirmed by the lack of alcohol-evoked conditioned place preference. Plasma alcohol concentrations of H3R KO and WT mice were similar. There were no marked differences in brain biogenic amine levels in H3R KO mice compared with the control animals after alcohol drinking. In conclusion, the findings of this study provide evidence for the role of H3R receptor in alcohol-related behaviors, especially in alcohol drinking and alcohol reward. Thus, targeting H3Rs with a specific antagonist might be a potential means to treat alcoholism in the future. PMID:21654737

  5. Comparison of the roles of reactive oxygen and nitrogen intermediates in the host response to Mycobacterium tuberculosis using transgenic mice.

    PubMed

    Adams, L B; Dinauer, M C; Morgenstern, D E; Krahenbuhl, J L

    1997-01-01

    To study the role of reactive oxygen intermediates (ROI) and reactive nitrogen intermediates (RNI) in host response to Mycobacterium tuberculosis. M. tuberculosis infection (i.v.) was compared in B6 control and two strains of knockout (KO) mice. X-CGD mice with a nonfunctional allele for the gp91phox subunit of the phagocyte oxidase cytochrome b are unable to produce ROI whereas iNOS KO mice lack a functional inducible nitric oxide synthase (iNOS) gene and fail to make RNI. M. tuberculosis growth was markedly enhanced in the lungs of X-CGD mice compared to B6 mice, but was controlled in the spleen and liver. In iNOS KO mice, M. tuberculosis growth was exacerbated in the spleen, but was unremarkable in the lungs compared to B6 mice until later (Day 60) in the infection. In vitro, X-CGD alveolar and peritoneal macrophages (M phi) produced no ROI, but did produce RNI and inhibited growth of M. tuberculosis when activated with interferon gamma. iNOS KO M phi produced ROI, but failed to produce RNI and could not cope with M. tuberculosis in vitro when activated. The inhibition of M. tuberculosis growth observed in activated B6 and X-CGD M phi) was reversed in the presence of aminoguanidine. These KO mouse strains demonstrate the relative potent effects of ROI and RNI in resistance to M. tuberculosis and should prove useful for the study of regulatory and compensatory mechanisms of immunity.

  6. NMDA receptor agonists reverse impaired psychomotor and cognitive functions associated with hippocampal Hbegf-deficiency in mice.

    PubMed

    Sasaki, Keita; Omotuyi, Olaposi Idowu; Ueda, Mutsumi; Shinohara, Kazuyuki; Ueda, Hiroshi

    2015-12-04

    Structural and functional changes of the hippocampus are correlated with psychiatric disorders and cognitive dysfunctions. Genetic deletion of heparin-binding epidermal growth factor-like growth factor (HB-EGF), which is predominantly expressed in cortex and hippocampus, also causes similar psychiatric and cognitive dysfunctions, accompanying down-regulated NMDA receptor signaling. However, little is known of such dysfunctions in hippocampus-specific Hbegf cKO mice. We successfully developed hippocampus-specific cKO mice by crossbreeding floxed Hbegf and Gng7-Cre knock-in mice, as Gng7 promoter-driven Cre is highly expressed in hippocampal neurons as well as striatal medium spiny neurons. In mice lacking hippocampus Hbegf gene, there was a decreased neurogenesis in the subgranular zone (SGZ) of the dentate gyrus as well as down-regulation of PSD-95/NMDA-receptor-NR1/NR2B subunits and related NMDA receptor signaling. Psychiatric, social-behavioral and cognitive abnormalities were also observed in hippocampal cKO mice. Interestingly, D-cycloserine and nefiracetam, positive allosteric modulators (PAMs) of NMDA receptor reversed the apparent reduction in NMDA receptor signaling and most behavioral abnormalities. Furthermore, decreased SGZ neurogenesis in hippocampal cKO mice was reversed by nefiracetam. The present study demonstrates that PAMs of NMDA receptor have pharmacotherapeutic potentials to reverse down-regulated NMDA receptor signaling, neuro-socio-cognitive abnormalities and decreased neurogenesis in hippocampal cKO mice.

  7. Bexarotene protects against traumatic brain injury in mice partially through apolipoprotein E.

    PubMed

    Zhong, Jianjun; Cheng, Chongjie; Liu, Han; Huang, Zhijian; Wu, Yue; Teng, Zhipeng; He, Junchi; Zhang, Hongrong; Wu, Jinchuan; Cao, Fang; Jiang, Li; Sun, Xiaochuan

    2017-02-20

    Bexarotene has been proved to have neuroprotective effects in many animal models of neurological diseases. However, its neuroprotection in traumatic brain injury (TBI) is still unknown. This study aims to explore the neuroprotective effects of bexarotene on TBI and its possible mechanism. Controlled cortical impact (CCI) model was used to simulate TBI in C57BL/6 mice as well as APOE gene knockout (APOE-KO) mice. After CCI, mice were daily dosed with bexarotene or vehicle solution intraperitoneally. The motor function, learning and memory, inflammatory factors, microglia amount, apoptosis condition around injury site and main side-effects were all measured. The results showed that, after CCI, bexarotene treatment markedly improved the motor function and spatial memory in C57BL/6 compare to APOE-KO mice which showed no improvement. The inflammatory cytokines, microglia amount, cell apoptosis rate, and protein of cleaved caspase-3 around the injury site were markedly upregulated after TBI in both C57BL/6 and APOE-KO mice, and all these upregulation were significantly mitigated by bexarotene treatment in C57BL/6 mice, but not in APOE-KO mice. No side-effects were detected after consecutive administration. Taken together, bexarotene inhibits the inflammatory response as well as cell apoptosis and improves the neurological function of mice after TBI partially through apolipoprotein E. This may make it a promising candidate for the therapeutic treatment after TBI. Copyright © 2016. Published by Elsevier Ltd.

  8. Identification of an Unfavorable Immune Signature in Advanced Lung Tumors from Nrf2-Deficient Mice.

    PubMed

    Zhang, Di; Rennhack, Jonathan; Andrechek, Eran R; Rockwell, Cheryl E; Liby, Karen T

    2018-04-16

    Activation of the nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway in normal cells inhibits carcinogenesis, whereas constitutive activation of Nrf2 in cancer cells promotes tumor growth and chemoresistance. However, the effects of Nrf2 activation in immune cells during lung carcinogenesis are poorly defined and could either promote or inhibit cancer growth. Our studies were designed to evaluate tumor burden and identify immune cell populations in the lungs of Nrf2 knockout (KO) versus wild-type (WT) mice challenged with vinyl carbamate. Nrf2 KO mice developed lung tumors earlier than the WT mice and exhibited more and larger tumors over time, even at late stages. T cell populations were lower in the lungs of Nrf2 KO mice, whereas tumor-promoting macrophages and myeloid-derived suppressor cells were elevated in the lungs and spleen, respectively, of Nrf2 KO mice relative to WT mice. Moreover, 34 immune response genes were significantly upregulated in tumors from Nrf2 KO mice, especially a series of cytokines (Cxcl1, Csf1, Ccl9, Cxcl12, etc.) and major histocompatibility complex antigens that promote tumor growth. Our studies discovered a novel immune signature, characterized by the infiltration of tumor-promoting immune cells, elevated cytokines, and increased expression of immune response genes in the lungs and tumors of Nrf2 KO mice. A complementary profile was also found in lung cancer patients, supporting the clinical significance of our findings. Overall, our results confirmed a protective role for Nrf2 in late-stage carcinogenesis and, unexpectedly, suggest that activation of Nrf2 in immune cells may be advantageous for preventing or treating lung cancer. Antioxid. Redox Signal. 00, 000-000.

  9. Chromatin breakdown by deoxyribonuclease1 promotes acetaminophen-induced liver necrosis: an ultrastructural and histochemical study on male CD-1 mice.

    PubMed

    Jacob, Monika; Mannherz, Hans Georg; Napirei, Markus

    2007-07-01

    We analyzed in male wild-type (WT) and Dnase1 knockout (KO) CD-1 mice after acetaminophen (APAP)-intoxication the hepatolobular distribution of APAP-adducts in relation to DNA-damage by terminal deoxyribonucleotidyl-transferase dUTP nick end-labeling (TUNEL), the ultrastructural alterations of hepatocellular morphology and the intracellular localization of Dnase1. Treatment of WT-mice with 600 mg/kg APAP led to extensive pericentral necrosis. Electron microscopy (EM) demonstrated vesiculation of the rough endoplasmatic reticulum and swelling of mitochondria. Pericentral WT-hepatocyte nuclei exhibited pyknosis, karyorrhexis and karyolysis. In contrast, livers from treated KO-mice exhibited almost normal light microscopical structure and EM revealed only mild signs of hepatocellular damage. In WT-mice several layers of pericentral hepatocytes displayed APAP-adduct formation and subsequent DNA-damage, whereas in KO-animals only few cells were affected. Serum aminotransferases rose similarly in both mouse strains up to 12 h, thereafter increased only in WT-mice. Immunogold-EM revealed the translocation of Dnase1 from the rER into the nuclei of treated WT-mice. In KO-mice, APAP-adduct formation was retarded and less extensive suggesting that detoxification of APAP must have been more effective in KO-mice possibly due to the lack of energy depletion otherwise caused by Dnase1-induced DNA-damage in WT-mice.

  10. Aromatase Deficient Female Mice Demonstrate Altered Expression of Molecules Critical for Renal Calcium Reabsorption

    NASA Astrophysics Data System (ADS)

    Öz, Orhan K.; Hajibeigi, Asghar; Cummins, Carolyn; van Abel, Monique; Bindels, René J.; Kuro-o, Makoto; Pak, Charles Y. C.; Zerwekh, Joseph E.

    2007-04-01

    The incidence of kidney stones increases in women after the menopause, suggesting a role for estrogen deficiency. In order to determine if estrogen may be exerting an effect on renal calcium reabsorption, we measured urinary calcium excretion in the aromatase-deficient female mouse (ArKO) before and following estrogen therapy. ArKO mice had hypercalciuria that corrected during estrogen administration. To evaluate the mechanism by which estrogen deficiency leads to hypercalciuria, we examined the expression of several proteins involved in distal tubule renal calcium reabsorption, both at the message and protein levels. Messenger RNA levels of TRPV5, TRPV6, calbindin-D28K, the Na+/Ca++ exchanger (NCX1), and the plasma membrane calcium ATPase (PMCA1b) were significantly decreased in kidneys of ArKO mice. On the other hand, klotho mRNA levels were elevated in kidneys of ArKO mice. ArKO renal protein extracts had lower levels of calbindin-D28K but higher levels of the klotho protein. Immunochemistry demonstrated increased klotho expression in ArKO kidneys. Estradiol therapy normalized the expression of TRPV5, calbindin-D28K, PMCA1b and klotho. Taken together, these results demonstrate that estrogen deficiency produced by aromatase inactivation is sufficient to produce a renal leak of calcium and consequent hypercalciuria. This may represent one mechanism leading to the increased incidence of kidney stones following the menopause in women.

  11. A2AR Binding Kinetics in the Ligand Depletion Regime.

    PubMed

    McNeely, Patrick M; Naranjo, Andrea N; Forsten-Williams, Kimberly; Robinson, Anne Skaja

    2017-02-01

    Ligand binding plays a fundamental role in stimulating the downstream signaling of membrane receptors. Here, ligand-binding kinetics of the full-length human adenosine A 2A receptor (A 2A R) reconstituted in detergent micelles were measured using a fluorescently labeled ligand via fluorescence anisotropy. Importantly, to optimize the signal-to-noise ratio, these experiments were conducted in the ligand depletion regime. In the ligand depletion regime, the assumptions used to determine analytical solutions for one-site binding models for either one or two ligands in competition are no longer valid. We therefore implemented a numerical solution approach to analyze kinetic binding data as experimental conditions approach the ligand depletion regime. By comparing the results from the numerical and the analytical solutions, we highlight the ligand-receptor ratios at which the analytical solution begins to lose predictive accuracy. Using the numerical solution approach, we determined the kinetic rate constants of the fluorescent ligand, FITC-APEC, and those for three unlabeled ligands using competitive association experiments. The association and dissociation rate constants of the unlabeled ligands determined from the competitive association experiments were then independently validated using competitive dissociation data. Based on this study, a numerical solution is recommended to determine kinetic ligand-binding parameters for experiments conducted in the ligand-depletion regime.

  12. Memantine, an NMDA receptor antagonist, improves working memory deficits in DGKβ knockout mice.

    PubMed

    Kakefuda, Kenichi; Ishisaka, Mitsue; Tsuruma, Kazuhiro; Shimazawa, Masamitsu; Hara, Hideaki

    2016-09-06

    Diacylglycerol kinase (DGK) β is a type 1 isozyme of the DGK family. We previously reported that DGKβ was deeply involved in neurite spine formation, and DGKβ knockout (KO) mice exhibited behavioral abnormalities concerning spine formation, such as cognitive, emotional, and attentional impairment. Moreover, some of these abnormalities were ameliorated by the administration of a mood stabilizer. However, there is no data about how memory-improving drugs used in the treatment of Alzheimer's disease affect DGKβ KO mice. In the present study, we evaluated the effect of an anti-Alzheimer's drug, memantine on the working memory deficit observed in DGKβ KO mice. In the Y-maze test, the administration of memantine significantly improved working memory of DGKβ KO mice. We also found that the expression levels of the NR2A and NR2B N-methyl-d-aspartate (NMDA) receptor subunits were increased in the prefrontal cortex, but decreased in the hippocampus of DGKβ KO mice. These altered expression levels of NR2 subunits might be related to the effect of an NMDA receptor antagonist, memantine. Taken together, these findings may support the hypothesis that DGKβ has a pivotal role in cognitive function. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Cortical Structure Alterations and Social Behavior Impairment in p50-Deficient Mice.

    PubMed

    Bonini, Sara Anna; Mastinu, Andrea; Maccarinelli, Giuseppina; Mitola, Stefania; Premoli, Marika; La Rosa, Luca Rosario; Ferrari-Toninelli, Giulia; Grilli, Mariagrazia; Memo, Maurizio

    2016-06-01

    Alterations in genes that regulate neurodevelopment can lead to cortical malformations, resulting in malfunction during postnatal life. The NF-κB pathway has a key role during neurodevelopment by regulating the maintenance of the neural progenitor cell pool and inhibiting neuronal differentiation. In this study, we evaluated whether mice lacking the NF-κB p50 subunit (KO) present alterations in cortical structure and associated behavioral impairment. We found that, compared with wild type (WT), KO mice at postnatal day 2 present an increase in radial glial cells, an increase in Reelin protein expression levels, in addition to an increase of specific layer thickness. Moreover, adult KO mice display abnormal columnar organization in the somatosensory cortex, a specific decrease in somatostatin- and parvalbumin-expressing interneurons, altered neurite orientation, and a decrease in Synapsin I protein levels. Concerning behavior, KO mice, in addition to an increase in locomotor and exploratory activity, display impairment in social behaviors, with a reduction in social interaction. Finally, we found that risperidone treatment decreased hyperactivity of KO mice, but had no effect on defective social interaction. Altogether, these data add complexity to a growing body of data, suggesting a link between dysregulation of the NF-κB pathway and neurodevelopmental disorders pathogenesis. © The Author 2016. Published by Oxford University Press.

  14. Intragastric fat self-administration is impaired in GPR40/120 double knockout mice

    PubMed Central

    Sclafani, Anthony; Touzani, Khalid; Ackroff, Karen

    2015-01-01

    Mice acquire strong preferences for flavors paired with intragastric (IG) fat infusions. This IG fat conditioning is attenuated in double knockout (DoKO) mice missing GPR40 and GPR120 fatty acid receptors. Here we determined if GPR40/120 DoKO mice are also impaired in IG fat self-administration in an operant lick task. In daily 1-h sessions the mice were trained with a sipper spout that contained dry food pellets; licks on the spout triggered infusions of IG fat (Intralipid). The training sessions were followed by test sessions with an empty spout. GPR40/120 DoKO mice self-infused more 20% fat than wild type (WT) C57BL/6 mice in training with a food-baited spout (2.4 vs. 2.0 kcal/h) but self-infused less 20% fat than WT mice in empty spout tests (1.2 vs. 1.7 kcal/h). The DoKO mice also self-infused less 5% fat than WT mice (0.6 vs. 1.3 kcal/h) although both groups emitted more licks for 5% fat than 20% fat. The DoKO and WT mice did not differ, however, in their self-infusion of 12.5% glucose (1.5 vs. 1.6 kcal/h), which is isocaloric to 5% fat. A second 5% IL test showed that the DoKO mice reverted to a reduced self-infusion compared to WT mice. When the infusion was shifted to water, WT mice reduced licking in the first extinction session, whereas DoKO mice were less sensitive to the absence of infused fat. Our results indicate that post-oral GPR40/120 signaling is not required to process IG fat infusions in food-baited spout training sessions but contributes to post-oral fat reinforcement in empty spout tests and flavor conditioning tests. PMID:25911263

  15. Fasting-induced myocardial lipid accumulation in long-chain acyl-CoA dehydrogenase knockout mice is accompanied by impaired left ventricular function.

    PubMed

    Bakermans, Adrianus J; Geraedts, Tom R; van Weeghel, Michel; Denis, Simone; João Ferraz, Maria; Aerts, Johannes M F G; Aten, Jan; Nicolay, Klaas; Houten, Sander M; Prompers, Jeanine J

    2011-09-01

    Lipotoxicity may be a key contributor to the pathogenesis of cardiac abnormalities in mitochondrial long-chain fatty acid β-oxidation (FAO) disorders. Few data are available on myocardial lipid levels and cardiac performance in FAO deficiencies. The purpose of this animal study is to assess fasting-induced changes in cardiac morphology, function, and triglyceride (TG) storage as a consequence of FAO deficiency in a noninvasive fashion. MRI and proton magnetic resonance spectroscopy ((1)H-MRS) were applied in vivo in long-chain acyl-CoA dehydrogenase (LCAD) knockout (KO) mice and wild-type (WT) mice (n=8 per genotype). Fasting was used to increase the heart's dependency on FAO for maintenance of energy homeostasis. In vivo data were complemented with ex vivo measurements of myocardial lipids. Left ventricular (LV) mass was higher in LCAD KO mice compared with WT mice (P<0.05), indicating LV myocardial hypertrophy. Myocardial TG content was higher in LCAD KO mice at baseline (P<0.001) and further increased in fasted LCAD KO mice (P<0.05). Concomitantly, LV ejection fraction (P<0.01) and diastolic filling rate (P<0.01) decreased after fasting, whereas these functional parameters did not change in fasted WT mice. Myocardial ceramide content was higher in fasted LCAD KO mice compared with fasted WT mice (P<0.05). Using a noninvasive approach, this study reveals accumulation of myocardial TG in LCAD KO mice. Toxicity of accumulating lipid metabolites such as ceramides may be responsible for the fasting-induced impairment of cardiac function observed in the LCAD KO mouse.

  16. Loss of epithelial FAM20A in mice causes amelogenesis imperfecta, tooth eruption delay and gingival overgrowth.

    PubMed

    Li, Li-Li; Liu, Pei-Hong; Xie, Xiao-Hua; Ma, Su; Liu, Chao; Chen, Li; Qin, Chun-Lin

    2016-06-30

    FAM20A has been studied to a very limited extent. Mutations in human FAM20A cause amelogenesis imperfecta, gingival fibromatosis and kidney problems. It would be desirable to systemically analyse the expression of FAM20A in dental tissues and to assess the pathological changes when this molecule is specifically nullified in individual tissues. Recently, we generated mice with a Fam20A-floxed allele containing the beta-galactosidase reporter gene. We analysed FAM20A expression in dental tissues using X-Gal staining, immunohistochemistry and in situ hybridization, which showed that the ameloblasts in the mouse mandibular first molar began to express FAM20A at 1 day after birth, and the reduced enamel epithelium in erupting molars expressed a significant level of FAM20A. By breeding K14-Cre mice with Fam20A(flox/flox) mice, we created K14-Cre;Fam20A(flox/flox) (conditional knock out, cKO) mice, in which Fam20A was inactivated in the epithelium. We analysed the dental tissues of cKO mice using X-ray radiography, histology and immunohistochemistry. The molar enamel matrix in cKO mice was much thinner than normal and was often separated from the dentinoenamel junction. The Fam20A-deficient ameloblasts were non-polarized and disorganized and were detached from the enamel matrix. The enamel abnormality in cKO mice was consistent with the diagnosis of amelogenesis imperfecta. The levels of enamelin and matrix metalloproteinase 20 were lower in the ameloblasts and enamel of cKO mice than the normal mice. The cKO mice had remarkable delays in the eruption of molars and hyperplasia of the gingival epithelium. The findings emphasize the essential roles of FAM20A in the development of dental and oral tissues.

  17. Loss of epithelial FAM20A in mice causes amelogenesis imperfecta, tooth eruption delay and gingival overgrowth

    PubMed Central

    Li, Li-Li; Liu, Pei-Hong; Xie, Xiao-Hua; Ma, Su; Liu, Chao; Chen, Li; Qin, Chun-Lin

    2016-01-01

    FAM20A has been studied to a very limited extent. Mutations in human FAM20A cause amelogenesis imperfecta, gingival fibromatosis and kidney problems. It would be desirable to systemically analyse the expression of FAM20A in dental tissues and to assess the pathological changes when this molecule is specifically nullified in individual tissues. Recently, we generated mice with a Fam20A-floxed allele containing the beta-galactosidase reporter gene. We analysed FAM20A expression in dental tissues using X-Gal staining, immunohistochemistry and in situ hybridization, which showed that the ameloblasts in the mouse mandibular first molar began to express FAM20A at 1 day after birth, and the reduced enamel epithelium in erupting molars expressed a significant level of FAM20A. By breeding K14-Cre mice with Fam20Aflox/flox mice, we created K14-Cre;Fam20Aflox/flox (conditional knock out, cKO) mice, in which Fam20A was inactivated in the epithelium. We analysed the dental tissues of cKO mice using X-ray radiography, histology and immunohistochemistry. The molar enamel matrix in cKO mice was much thinner than normal and was often separated from the dentinoenamel junction. The Fam20A-deficient ameloblasts were non-polarized and disorganized and were detached from the enamel matrix. The enamel abnormality in cKO mice was consistent with the diagnosis of amelogenesis imperfecta. The levels of enamelin and matrix metalloproteinase 20 were lower in the ameloblasts and enamel of cKO mice than the normal mice. The cKO mice had remarkable delays in the eruption of molars and hyperplasia of the gingival epithelium. The findings emphasize the essential roles of FAM20A in the development of dental and oral tissues. PMID:27281036

  18. The M2 muscarinic receptors are essential for signaling in the heart left ventricle during restraint stress in mice.

    PubMed

    Tomankova, Hana; Valuskova, Paulina; Varejkova, Eva; Rotkova, Jana; Benes, Jan; Myslivecek, Jaromir

    2015-01-01

    We hypothesized that muscarinic receptors (MRs) in the heart have a role in stress responses and thus investigated changes in MR signaling (gene expression, number of receptors, adenylyl cyclase (AC), phospholipase C (PLC), protein kinase A and C (PKA and PKC) and nitric oxide synthase [NOS]) in the left ventricle, together with telemetric measurement of heart rate (HR) in mice (wild type [WT] and M2 knockout [KO]) during and after one (1R) or seven sessions (7R) of restraint stress (seven mice per group). Stress decreased M2 MR mRNA and cell surface MR in the left ventricle in WT mice. In KO mice, 1R, but not 7R, decreased surface MR. Similarly, AC activity was decreased in WT mice after 1R and 7R, whereas in KO mice, there was no change. PLC activity was also decreased after 1R in WT and KO mice. This is in accord with the concept that cAMP is a key player in HR regulation. No change was found with stress in NOS activity. Amount of AC and PKA protein was not changed, but was altered for PKC isoenzymes (PKCα, β, γ, η and ϵ (increased) in KO mice, and PKCι (increased) in WT mice). KO mice were more susceptible to stress as shown by inability to compensate HR during 120 min following repeated stress. The results imply that not only M2 but also M3 are involved in stress signaling and in allostasis. We conclude that for a normal stress response, the expression of M2 MR to mediate vagal responses is essential.

  19. Microdialysis in freely moving mice: determination of acetylcholine, serotonin and noradrenaline release in galanin transgenic mice.

    PubMed

    Kehr, J; Yoshitake, T; Wang, F H; Wynick, D; Holmberg, K; Lendahl, U; Bartfai, T; Yamaguchi, M; Hökfelt, T; Ogren, S O

    2001-08-15

    In the present study, we describe micro-surgical methods for simultaneous implantation of a microdialysis probe and an intraventricular injection cannula via their respective guide cannulas into the mouse brain. Basal and stimulated release of acetylcholine (ACh), serotonin (5-HT) and noradrenaline (NA) was determined in the ventral hippocampus of freely moving mice. NA and 5-HT were determined in one run by a newly developed HPLC method based on precolumn derivatization with benzylamine and fluorescence detection. The mice with a loss-of-function mutation of the galanin gene (KO) and the mice that over-expressed galanin (OE) were studied. No significant differences in basal, potassium-stimulated or scopolamine-induced extracellular ACh levels were observed in 4-month-old wild-type (WT) and KO mice. In the aged, 10-month-old animals, the basal extracellular ACh levels were significantly reduced in both WT and KO groups. Galanin (1 nmol i.c.v.) caused a significant reduction of basal extracellular NA by about 40% in both WT and galanin OE mice, however, in the latter group the effect was delayed by almost 2 h. A 10-min forced swimming stress caused a higher increase in release of NA and 5-HT in the OE group than in the corresponding WT mice. Finally, venlafaxin (10 mg/kg i.p.) increased extracellular NA to 400% of the control values in the CBA mice, but only to 250% in the C57BL mice. It is concluded that galanin may play an important role in the cholinergic mechanisms underlying cognitive disorders. Furthermore, modulation by galanin and by behavioral activation, of NA and 5-HT neurotransmission in galanin over-expressing mice indicates its possible role in the aetiology of mood disorders.

  20. High-Fat Diet Induces Unexpected Fatal Uterine Infections in Mice with aP2-Cre-mediated Deletion of Estrogen Receptor Alpha.

    PubMed

    Ban, Zsofia; Maurischat, Paul; Benz, Verena; Brix, Sarah; Sonnenburg, Anna; Schuler, Gerhard; Klopfleisch, Robert; Rothe, Michael; Gustafsson, Jan-Åke; Foryst-Ludwig, Anna; Kintscher, Ulrich

    2017-02-24

    Estrogen receptor alpha (ERα) is a major regulator of metabolic processes in obesity. In this study we aimed to define the relevance of adipose tissue ERα during high-fat diet (HFD)-induced obesity using female aP2-Cre -/+ /ERα fl/fl mice (atERαKO). HFD did not affect body weight or glucose metabolism in atERαKO- compared to control mice. Surprisingly, HFD feeding markedly increased mortality in atERαKO mice associated with a destructive bacterial infection of the uterus driven by commensal microbes, an alteration likely explaining the absence of a metabolic phenotype in HFD-fed atERαKO mice. In order to identify a mechanism of the exaggerated uterine infection in HFD-fed atERαKO mice, a marked reduction of uterine M2-macrophages was detected, a cell type relevant for anti-microbial defence. In parallel, atERαKO mice exhibited elevated circulating estradiol (E2) acting on E2-responsive tissue/cells such as macrophages. Accompanying cell culture experiments showed that despite E2 co-administration stearic acid (C18:0), a fatty acid elevated in plasma from HFD-fed atERαKO mice, blocks M2-polarization, a process known to be enhanced by E2. In this study we demonstrate an unexpected phenotype in HFD-fed atERαKO involving severe uterine bacterial infections likely resulting from a previously unknown negative interference between dietary FAs and ERα-signaling during anti-microbial defence.

  1. Properties of extensor digitorum longus muscle and skinned fibers from adult and aged male and female Actn3 knockout mice.

    PubMed

    Chan, Stephen; Seto, Jane T; Houweling, Peter J; Yang, Nan; North, Kathryn N; Head, Stewart I

    2011-01-01

    Absence of α-actinin-3, encoded by the ACTN3 "speed gene," is associated with poorer sprinting performance in athletes and a slowing of relaxation in fast-twitch muscles of Actn3 knockout (KO) mice. Our first aim was to investigate, at the individual-fiber level, possible mechanisms for this slowed relaxation. Our second aim was to characterize the contractile properties of whole extensor digitorum longus (EDL) muscles from KO mice by age and gender. We examined caffeine-induced Ca(2+) release in mechanically skinned EDL fibers from KO mice, and measured isolated whole EDL contractile properties. The sarcoplasmic reticulum of KO muscle fibers loaded Ca(2+) more slowly than that of wild-types (WTs). Whole KO EDL muscles had longer twitch and tetanus relaxation times than WTs, and reduced mass and cross-sectional area. These effects occurred in both male and female mice, but they diminished with age. These changes in KO muscles and fibers help to explain the effects of α-actinin-3 deficiency observed in athletes. Copyright © 2010 Wiley Periodicals, Inc.

  2. Upregulation of axon guidance molecules in the adult central nervous system of Nogo-A knockout mice restricts neuronal growth and regeneration.

    PubMed

    Kempf, Anissa; Montani, Laura; Petrinovic, Marija M; Schroeter, Aileen; Weinmann, Oliver; Patrignani, Andrea; Schwab, Martin E

    2013-12-01

    Adult central nervous system axons show restricted growth and regeneration properties after injury. One of the underlying mechanisms is the activation of the Nogo-A/Nogo receptor (NgR1) signaling pathway. Nogo-A knockout (KO) mice show enhanced regenerative growth in vivo, even though it is less pronounced than after acute antibody-mediated neutralization of Nogo-A. Residual inhibition may involve a compensatory component. By mRNA expression profiling and immunoblots we show increased expression of several members of the Ephrin/Eph and Semaphorin/Plexin families of axon guidance molecules, e.g. EphrinA3 and EphA4, in the intact spinal cord of adult Nogo-A KO vs. wild-type (WT) mice. EphrinA3 inhibits neurite outgrowth of EphA4-positive neurons in vitro. In addition, EphrinA3 KO myelin extracts are less growth-inhibitory than WT but more than Nogo-A KO myelin extracts. EphA4 KO cortical neurons show decreased growth inhibition on Nogo-A KO myelin as compared with WT neurons, supporting increased EphA4-mediated growth inhibition in Nogo-A KO mice. Consistently, in vivo, Nogo-A/EphA4 double KO mice show increased axonal sprouting and regeneration after spinal cord injury as compared with EphA4 KO mice. Our results reveal the upregulation of developmental axon guidance cues following constitutive Nogo-A deletion, e.g. the EphrinA3/EphA4 ligand/receptor pair, and support their role in restricting neurite outgrowth in the absence of Nogo-A. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  3. CaSR-mediated interactions between calcium and magnesium homeostasis in mice

    PubMed Central

    Quinn, Stephen J.; Thomsen, Alex R. B.; Egbuna, Ogo; Pang, Jian; Baxi, Khanjan; Goltzman, David; Pollak, Martin

    2013-01-01

    Calcium (Ca) and magnesium (Mg) homeostasis are interrelated and share common regulatory hormones, including parathyroid hormone (PTH) and vitamin D. However, the role of the calcium-sensing receptor (CaSR) in Mg homeostasis in vivo is not well understood. We sought to investigate the interactions between Mg and Ca homeostasis using genetic mouse models with targeted inactivation of PTH (PTH KO) or both PTH and the calcium-sensing receptor (CaSR) (double knockout, DKO). Serum Mg is lower in PTH KO and DKO mice than in WT mice on standard chow, whereas supplemental dietary Ca leads to equivalent Mg levels for all three genotypes. Mg loading increases serum Mg in all genotypes; however, the increase in serum Mg is most pronounced in the DKO mice. Serum Ca is increased with Mg loading in the PTH KO and DKO mice but not in the WT mice. Here, too, the hypercalcemia is much greater in the DKO mice. Serum and especially urinary phosphate are reduced during Mg loading, which is likely due to intestinal chelation of phosphate by Mg. Mg loading decreases serum PTH in WT mice and increases serum calcitonin in both WT and PTH KO mice but not DKO mice. Furthermore, Mg loading elevates serum 1,25-dihydroxyvitamin D in all genotypes, with greater effects in PTH KO and DKO mice, possibly due to reduced levels of serum phosphorus and FGF23. These hormonal responses to Mg loading and the CaSR's role in regulating renal function may help to explain changes in serum Mg and Ca found during Mg loading. PMID:23360827

  4. ABCA1 Deficiency Affects Basal Cognitive Deficits and Dendritic Density in Mice.

    PubMed

    Fitz, Nicholas F; Carter, Alexis Y; Tapias, Victor; Castranio, Emilie L; Kodali, Ravindra; Lefterov, Iliya; Koldamova, Radosveta

    2017-01-01

    ATP-binding cassette transporter A1 (ABCA1) mediates cholesterol efflux to lipid-free apolipoproteins and regulates the generation of high density lipoproteins. Previously, we have shown that lack of Abca1 significantly increases amyloid deposition and cognitive deficits in Alzheimer's disease model mice expressing human amyloid-β protein precursor (APP). The goal of this study was to determine if ABCA1 plays a role in memory deficits caused by amyloid-β (Aβ) oligomers and examine neurite architecture of pyramidal hippocampal neurons. Our results confirm previous findings that Abca1 deficiency significantly impairs spatial memory acquisition and retention in the Morris water maze and long-term memory in novel object recognition of APP transgenic mice at a stage of early amyloid pathology. Neither test demonstrated a significant difference between Abca1ko and wild-type (WT) mice. We also examined the effect of intra-hippocampal infused Aβ oligomers on cognitive performance of Abca1ko mice, compared to control infusion of scrambled Aβ peptide. Age-matched WT mice undergoing the same infusions were also used as controls. In this model system, we found a statistically significant difference between WT and Abca1ko mice infused with scrambled Aβ, suggesting that Abca1ko mice are vulnerable to the effect of mild stresses. Moreover, examination of neurite architecture in the hippocampi revealed a significant decrease in neurite length, number of neurite segments, and branches in Abca1ko mice when compared to WT mice. We conclude that mice lacking ABCA1 have basal cognitive deficits that prevent them from coping with additional stressors, which is in part due to impairment of neurite morphology in the hippocampus.

  5. ABCA1 Deficiency Affects Basal Cognitive Deficits and Dendritic Density in Mice

    PubMed Central

    Fitz, Nicholas F.; Carter, Alexis Y.; Tapias, Victor; Castranio, Emilie L.; Kodali, Ravindra; Lefterov, Iliya; Koldamova, Radosveta

    2017-01-01

    ATP-binding cassette transporter A1 (ABCA1) mediates cholesterol efflux to lipid-free apolipoproteins and regulates the generation of high density lipoproteins. Previously, we have shown that lack of Abca1 significantly increases amyloid deposition and cognitive deficits in Alzheimer’s disease model mice expressing human amyloid-β protein precursor (APP). The goal of this study was to determine if ABCA1 plays a role in memory deficits caused by amyloid-β (Aβ) oligomers and examine neurite architecture of pyramidal hippocampal neurons. Our results confirm previous findings that Abca1 deficiency significantly impairs spatial memory acquisition and retention in the Morris water maze and long-term memory in novel object recognition of APP transgenic mice at a stage of early amyloid pathology. Neither test demonstrated a significant difference between Abca1ko and wild-type (WT) mice. We also examined the effect of intra-hippocampal infused Aβ oligomers on cognitive performance of Abca1ko mice, compared to control infusion of scrambled Aβ peptide. Age-matched WT mice undergoing the same infusions were also used as controls. In this model system, we found a statistically significant difference between WT and Abca1ko mice infused with scrambled Aβ, suggesting that Abca1ko mice are vulnerable to the effect of mild stresses. Moreover, examination of neurite architecture in the hippocampi revealed a significant decrease in neurite length, number of neurite segments, and branches in Abca1ko mice when compared to WT mice. We conclude that mice lacking ABCA1 have basal cognitive deficits that prevent them from coping with additional stressors, which is in part due to impairment of neurite morphology in the hippocampus. PMID:28106559

  6. Metabolomic profiles of arsenic (+3 oxidation state) methyltransferase knockout mice: Effect of sex and arsenic exposure

    PubMed Central

    Huang, Madelyn C.; Douillet, Christelle; Su, Mingming; Zhou, Kejun; Wu, Tao; Chen, Wenlian; Galanko, Joseph A.; Drobná, Zuzana; Saunders, R. Jesse; Martin, Elizabeth; Fry, Rebecca C.; Jia, Wei; Stýblo, Miroslav

    2016-01-01

    Arsenic (+3 oxidation state) methyltransferase (As3mt) is the key enzyme in the pathway for methylation of inorganic arsenic (iAs). Altered As3mt expression and AS3MT polymorphism have been linked to changes in iAs metabolism and in susceptibility to iAs toxicity in laboratory models and in humans. As3mt-knockout mice have been used to study the association between iAs metabolism and adverse effects of iAs exposure. However, little is known about systemic changes in metabolism of these mice and how these changes lead to their increased susceptibility to iAs toxicity. Here, we compared plasma and urinary metabolomes of male and female wild-type (WT) and As3mt-KO (KO) C57BL6 mice and examined metabolomic shifts associated with iAs exposure in drinking water. Surprisingly, exposure to 1 ppm As elicited only small changes in the metabolite profiles of either WT or KO mice. In contrast, comparisons of KO mice with WT mice revealed significant differences in plasma and urinary metabolites associated with lipid (phosphatidylcholines, cytidine, acyl-carnitine), amino acid (hippuric acid, acetylglycine, urea), and carbohydrate (L-sorbose, galactonic acid, gluconic acid) metabolism. Notably, most of these differences were sex-specific. Sex-specific differences were also found between WT and KO mice in plasma triglyceride and lipoprotein cholesterol levels. Some of the differentially changed metabolites (phosphatidylcholines, carnosine, and sarcosine) are substrates or products of reactions catalyzed by other methyltransferases. These results suggest that As3mt KO alters major metabolic pathways in a sex-specific manner, independent of iAs treatment, and that As3mt may be involved in other cellular processes beyond iAs methylation. PMID:26883664

  7. 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

  8. 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).

  9. Metabolomic profiles of arsenic (+3 oxidation state) methyltransferase knockout mice: effect of sex and arsenic exposure.

    PubMed

    Huang, Madelyn C; Douillet, Christelle; Su, Mingming; Zhou, Kejun; Wu, Tao; Chen, Wenlian; Galanko, Joseph A; Drobná, Zuzana; Saunders, R Jesse; Martin, Elizabeth; Fry, Rebecca C; Jia, Wei; Stýblo, Miroslav

    2017-01-01

    Arsenic (+3 oxidation state) methyltransferase (As3mt) is the key enzyme in the pathway for methylation of inorganic arsenic (iAs). Altered As3mt expression and AS3MT polymorphism have been linked to changes in iAs metabolism and in susceptibility to iAs toxicity in laboratory models and in humans. As3mt-knockout mice have been used to study the association between iAs metabolism and adverse effects of iAs exposure. However, little is known about systemic changes in metabolism of these mice and how these changes lead to their increased susceptibility to iAs toxicity. Here, we compared plasma and urinary metabolomes of male and female wild-type (WT) and As3mt-KO (KO) C57BL/6 mice and examined metabolomic shifts associated with iAs exposure in drinking water. Surprisingly, exposure to 1 ppm As elicited only small changes in the metabolite profiles of either WT or KO mice. In contrast, comparisons of KO mice with WT mice revealed significant differences in plasma and urinary metabolites associated with lipid (phosphatidylcholines, cytidine, acyl-carnitine), amino acid (hippuric acid, acetylglycine, urea), and carbohydrate (L-sorbose, galactonic acid, gluconic acid) metabolism. Notably, most of these differences were sex specific. Sex-specific differences were also found between WT and KO mice in plasma triglyceride and lipoprotein cholesterol levels. Some of the differentially changed metabolites (phosphatidylcholines, carnosine, and sarcosine) are substrates or products of reactions catalyzed by other methyltransferases. These results suggest that As3mt KO alters major metabolic pathways in a sex-specific manner, independent of iAs treatment, and that As3mt may be involved in other cellular processes beyond iAs methylation.

  10. Environmental Enrichment Ameliorates Behavioral Impairments Modeling Schizophrenia in Mice Lacking Metabotropic Glutamate Receptor 5.

    PubMed

    Burrows, Emma L; McOmish, Caitlin E; Buret, Laetitia S; Van den Buuse, Maarten; Hannan, Anthony J

    2015-07-01

    Schizophrenia arises from a complex interplay between genetic and environmental factors. Abnormalities in glutamatergic signaling have been proposed to underlie the emergence of symptoms, in light of various lines of evidence, including the psychotomimetic effects of NMDA receptor antagonists. Metabotropic glutamate receptor 5 (mGlu5) has also been implicated in the disorder, and has been shown to physically interact with NMDA receptors. To clarify the role of mGlu5-dependent behavioral expression by environmental factors, we assessed mGlu5 knockout (KO) mice after exposure to environmental enrichment (EE) or reared under standard conditions. The mGlu5 KO mice showed reduced prepulse inhibition (PPI), long-term memory deficits, and spontaneous locomotor hyperactivity, which were all attenuated by EE. Examining the cellular impact of genetic and environmental manipulation, we show that EE significantly increased pyramidal cell dendritic branching and BDNF protein levels in the hippocampus of wild-type mice; however, mGlu5 KO mice were resistant to these alterations, suggesting that mGlu5 is critical to these responses. A selective effect of EE on the behavioral response to the NMDA receptor antagonist MK-801 in mGlu5 KO mice was seen. MK-801-induced hyperlocomotion was further potentiated in enriched mGlu5 KO mice and treatment with MK-801 reinstated PPI disruption in EE mGlu5 KO mice only, a response that is absent under standard housing conditions. Together, these results demonstrate an important role for mGlu5 in environmental modulation of schizophrenia-related behavioral impairments. Furthermore, this role of the mGlu5 receptor is mediated by interaction with NMDA receptor function, which may inform development of novel therapeutics.

  11. Odor preference and olfactory memory are impaired in Olfaxin-deficient mice.

    PubMed

    Islam, Saiful; Ueda, Masashi; Nishida, Emika; Wang, Miao-Xing; Osawa, Masatake; Lee, Dongsoo; Itoh, Masanori; Nakagawa, Kiyomi; Tana; Nakagawa, Toshiyuki

    2018-06-01

    Olfaxin, which is a BNIP2 and Cdc42GAP homology (BCH) domain-containing protein, is predominantly expressed in mitral and tufted (M/T) cells in the olfactory bulb (OB). Olfaxin and Caytaxin, which share 56.3% amino acid identity, are similar in their glutamatergic terminal localization, kidney-type glutaminase (KGA) interaction, and caspase-3 substrate. Although the deletion of Caytaxin protein causes human Cayman ataxia and ataxia in the mutant mouse, the function of Olfaxin is largely unknown. In this study, we generated Prune2 gene mutant mice (Prune2 Ex16-/- ; knock out [KO] mice) using the CRISPR/Cas9 system, during which the exon 16 containing start codon of Olfaxin mRNA was deleted. Exon 16 has 80 nucleotides and is contained in four of five Prune2 isoforms, including PRUNE2, BMCC1, BNIPXL, and Olfaxin/BMCC1s. The levels of Olfaxin mRNA and Olfaxin protein in the OB and piriform cortex of KO mice significantly decreased. Although Prune2 mRNA also significantly decreased in the spinal cord, the gross anatomy of the spinal cord and dorsal root ganglion (DRG) was intact. Further, disturbance of the sensory and motor system was not observed in KO mice. Therefore, in the current study, we examined the role of Olfaxin in the olfactory system where PRUNE2, BMCC1, and BNIPXL are scarcely expressed. Odor preference was impaired in KO mice using opposite-sex urinary scents as well as a non-social odor stimulus (almond). Results of the odor-aversion test demonstrated that odor-associative learning was disrupted in KO mice. Moreover, the NMDAR2A/NMDAR2B subunits switch in the piriform cortex was not observed in KO mice. These results indicated that Olfaxin may play a critical role in odor preference and olfactory memory. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Environmental Enrichment Ameliorates Behavioral Impairments Modeling Schizophrenia in Mice Lacking Metabotropic Glutamate Receptor 5

    PubMed Central

    Burrows, Emma L; McOmish, Caitlin E; Buret, Laetitia S; Van den Buuse, Maarten; Hannan, Anthony J

    2015-01-01

    Schizophrenia arises from a complex interplay between genetic and environmental factors. Abnormalities in glutamatergic signaling have been proposed to underlie the emergence of symptoms, in light of various lines of evidence, including the psychotomimetic effects of NMDA receptor antagonists. Metabotropic glutamate receptor 5 (mGlu5) has also been implicated in the disorder, and has been shown to physically interact with NMDA receptors. To clarify the role of mGlu5-dependent behavioral expression by environmental factors, we assessed mGlu5 knockout (KO) mice after exposure to environmental enrichment (EE) or reared under standard conditions. The mGlu5 KO mice showed reduced prepulse inhibition (PPI), long-term memory deficits, and spontaneous locomotor hyperactivity, which were all attenuated by EE. Examining the cellular impact of genetic and environmental manipulation, we show that EE significantly increased pyramidal cell dendritic branching and BDNF protein levels in the hippocampus of wild-type mice; however, mGlu5 KO mice were resistant to these alterations, suggesting that mGlu5 is critical to these responses. A selective effect of EE on the behavioral response to the NMDA receptor antagonist MK-801 in mGlu5 KO mice was seen. MK-801-induced hyperlocomotion was further potentiated in enriched mGlu5 KO mice and treatment with MK-801 reinstated PPI disruption in EE mGlu5 KO mice only, a response that is absent under standard housing conditions. Together, these results demonstrate an important role for mGlu5 in environmental modulation of schizophrenia-related behavioral impairments. Furthermore, this role of the mGlu5 receptor is mediated by interaction with NMDA receptor function, which may inform development of novel therapeutics. PMID:25666312

  13. Endogenous murine tau promotes neurofibrillary tangles in 3xTg-AD mice without affecting cognition.

    PubMed

    Baglietto-Vargas, David; Kitazawa, Masashi; Le, Elaine J; Estrada-Hernandez, Tatiana; Rodriguez-Ortiz, Carlos J; Medeiros, Rodrigo; Green, Kim N; LaFerla, Frank M

    2014-02-01

    Recent studies on tauopathy animal models suggest that the concomitant expression of the endogenous murine tau delays the pathological accumulation of human tau, and interferes with the disease progression. To elucidate the role of endogenous murine tau in a model with both plaques and tangles, we developed a novel transgenic mouse model by crossing 3xTg-AD with mtauKO mice (referred to as 3xTg-AD/mtauKO mice). Therefore, this new model allows us to determine the pathological consequences of the murine tau. Here, we show that 3xTg-AD/mtauKO mice have lower tau loads in both soluble and insoluble fractions, and lower tau hyperphosphorylation level in the soluble fraction relative to 3xTg-AD mice. In the 3xTg-AD model endogenous mouse tau is hyperphosphorylated and significantly co-aggregates with human tau. Despite the deletion of the endogenous tau gene in 3xTg-AD/mtauKO mice, cognitive dysfunction was equivalent to 3xTg-AD mice, as there was no additional impairment on a spatial memory task, and thus despite increased tau phosphorylation, accumulation and NFTs in 3xTg-AD mice no further effects on cognition are seen. These findings provide better understanding about the role of endogenous tau to Alzheimer's disease (AD) pathology and for developing new AD models. © 2013.

  14. Mitochondrial and performance adaptations to exercise training in mice lacking skeletal muscle LKB1

    PubMed Central

    Tanner, Colby B.; Madsen, Steven R.; Hallowell, David M.; Goring, Darren M. J.; Moore, Timothy M.; Hardman, Shalene E.; Heninger, Megan R.; Atwood, Daniel R.

    2013-01-01

    LKB1 and its downstream targets of the AMP-activated protein kinase family are important regulators of many aspects of skeletal muscle cell function, including control of mitochondrial content and capillarity. LKB1 deficiency in skeletal and cardiac muscle (mLKB1-KO) greatly impairs exercise capacity. However, cardiac dysfunction in that genetic model prevents a clear assessment of the role of skeletal muscle LKB1 in the observed effects. Our purposes here were to determine whether skeletal muscle-specific knockout of LKB1 (skmLKB1-KO) decreases exercise capacity and mitochondrial protein content, impairs accretion of mitochondrial proteins after exercise training, and attenuates improvement in running performance after exercise training. We found that treadmill and voluntary wheel running capacity was reduced in skmLKB1-KO vs. control (CON) mice. Citrate synthase activity, succinate dehydrogenase activity, and pyruvate dehydrogenase kinase content were lower in KO vs. CON muscles. Three weeks of treadmill training resulted in significantly increased treadmill running performance in both CON and skmLKB1-KO mice. Citrate synthase activity increased significantly with training in both genotypes, but protein content and activity for components of the mitochondrial electron transport chain increased only in CON mice. Capillarity and VEGF protein was lower in skmLKB1-KO vs. CON muscles, but VEGF increased with training only in skmLKB1-KO. Three hours after an acute bout of muscle contractions, PGC-1α, cytochrome c, and VEGF gene expression all increased in CON but not skmLKB1-KO muscles. Our findings indicate that skeletal muscle LKB1 is required for accretion of some mitochondrial proteins but not for early exercise capacity improvements with exercise training. PMID:23982155

  15. The Influence of Shc Proteins on the Whole Body Energetic Response to Calorie Restriction Initiated in 3-Month-Old Mice

    PubMed Central

    Stern, Jennifer H.; Ramsey, Jon J.

    2014-01-01

    There is increasing evidence that Shc proteins play a role in energy metabolism, and we have previously reported that knockdown of Shc proteins influences the energetic response to acute (3 days) calorie restriction (CR) in 18-month-old mice. Whether Shc proteins play a role in the metabolic response to CR in younger mice has yet to be elucidated. Hence, we sought to determine the impact of 3 days and longer term (2 months) CR on energy expenditure (EE) and respiratory quotient (RQ) in 3 month-old Shc knockout (ShcKO) and wild-type (WT) mice. ShcKO mice decreased (P < 0.001) EE normalized for body weight (EEBW) by 3 days of CR, while no such change was observed in WT animals. However, both ShcKO and WT mice decreased (P < 0.001) EEBW at 2 months of CR and there were no differences in body weight between the ShcKO and WT mice at either 3 days or 2 months of CR. Consistent with increased fatty acid oxidation, only ShcKO mice maintained decreased (P < 0.001) 24 h RQ through 2 months of CR, suggesting that they were able to maintain increased fatty acid oxidation for a longer period of time than WT mice. These results indicate that Shc proteins may contribute to some of the acute energetic responses to CR. PMID:24967271

  16. Mice deficient in MyD88 Develop a Th2-dominant response and severe pathology in the upper genital tract following Chlamydia muridarum infection.

    PubMed

    Chen, Lili; Lei, Lei; Chang, Xiaotong; Li, Zhihong; Lu, Chunxue; Zhang, Xiaoyun; Wu, Yimou; Yeh, I-Tien; Zhong, Guangming

    2010-03-01

    MyD88, a key adaptor molecule required for many innate immunity receptor-activated signaling pathways, was evaluated in a Chlamydia muridarum urogenital tract infection model. Compared with wild-type mice, MyD88 knockout (KO) mice failed to produce significant levels of inflammatory cytokines in the genital tract during the first week of chlamydial infection. MyD88 KO mice developed a Th2-dominant whereas wild-type mice developed a Th1/Th17-dominant immune response after chlamydial infection. Despite the insufficient production of early inflammatory cytokines and lack of Th1/Th17-dominant adaptive immunity, MyD88 KO mice appeared to be as resistant to chlamydial intravaginal infection as wild-type mice based on the number of live organisms recovered from vaginal samples. However, significantly high numbers of chlamydial organisms were detected in the upper genital tract tissues of MyD88 KO mice. Consequently, MyD88 KO mice developed more severe pathology in the upper genital tract. These results together have demonstrated that MyD88-dependent signaling pathway is not only required for inflammatory cytokine production in the early phase of host response to chlamydial infection but also plays a critical role in the development of Th1/Th17 adaptive immunity, both of which may be essential for limiting ascending infection and reducing pathology of the upper genital tract by chlamydial organisms.

  17. Metallothionein-I/II Knockout Mice Aggravate Mitochondrial Superoxide Production and Peroxiredoxin 3 Expression in Thyroid after Excessive Iodide Exposure

    PubMed Central

    Zhang, Na; Wang, Lingyan; Duan, Qi; Lin, Laixiang; Ahmed, Mohamed; Wang, Tingting; Yao, Xiaomei

    2015-01-01

    Purpose. We aim to figure out the effect of metallothioneins on iodide excess induced oxidative stress in the thyroid. Methods. Eight-week-old MT-I/II knockout (MT-I/II KO) mice and background-matched wild-type (WT) mice were used. Mitochondrial superoxide production and peroxiredoxin (Prx) 3 expression were measured. Results. In in vitro study, more significant increases in mitochondrial superoxide production and Prx 3 expression were detected in the MT-I/II KO groups. In in vivo study, significantly higher concentrations of urinary iodine level were detected in MT-I/II KO mice in 100 HI group. Compared to the NI group, there was no significant difference existing in serum thyroid hormones level in either groups (P > 0.05), while the mitochondrial superoxide production was significantly increased in 100 HI groups with significantly increased LDH activity and decreased relative cell viability. Compared to WT mice, more significant changes were detected in MT-I/II KO mice in 100 HI groups. No significant differences were detected between the NI group and 10 HI group in both the MT-I/II KO and WT mice groups (P > 0.05). Conclusions. Iodide excess in a thyroid without MT I/II protection may result in strong mitochondrial oxidative stress, which further leads to the damage of thyrocytes. PMID:26101557

  18. Absence of perilipin 2 prevents hepatic steatosis, glucose intolerance and ceramide accumulation in alcohol-fed mice.

    PubMed

    Carr, Rotonya M; Peralta, Giselle; Yin, Xiaoyan; Ahima, Rexford S

    2014-01-01

    Perilipin 2 (Plin2) is a lipid droplet protein that has roles in both lipid and glucose homeostasis. An increase in Plin2 in liver is associated with the development of steatosis, glucose intolerance, and ceramide accumulation in alcoholic liver disease. We investigated the role of Plin2 on energy balance and glucose and lipid homeostasis in wildtype and Plin2 knockout (Plin2KO) mice chronically fed a Lieber-DeCarli liquid ethanol or control diet for six weeks. We performed in vivo measurements of energy intake and expenditure; body composition; and glucose tolerance. After sacrifice, liver was dissected for histology and lipid analysis. We found that neither genotype nor diet had a significant effect on final weight, body composition, or energy intake between WT and Plin2KO mice fed alcohol or control diets. Additionally, alcohol feeding did not affect oxygen consumption or carbon dioxide production in Plin2KO mice. We performed glucose tolerance testing and observed that alcohol feeding failed to impair glucose tolerance in Plin2KO mice. Most notably, absence of Plin2 prevented hepatic steatosis and ceramide accumulation in alcohol-fed mice. These changes were related to downregulation of genes involved in lipogenesis and triglyceride synthesis. Plin2KO mice chronically fed alcohol are protected from hepatic steatosis, glucose intolerance, and hepatic ceramide accumulation, suggesting a critical pathogenic role of Plin2 in experimental alcoholic liver disease.

  19. Knockout of the aryl hydrocarbon receptor results in distinct hepatic and renal phenotypes in rats and mice

    SciTech Connect

    Harrill, Joshua A.; Hukkanen, Renee R.; Lawson, Marie

    2013-10-15

    The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor which plays a role in the development of multiple tissues and is activated by a large number of ligands, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). In order to examine the roles of the AHR in both normal biological development and response to environmental chemicals, an AHR knockout (AHR-KO) rat model was created and compared with an existing AHR-KO mouse. AHR-KO rats harboring either 2-bp or 29-bp deletion mutation in exon 2 of the AHR were created on the Sprague–Dawley genetic background using zinc-finger nuclease (ZFN) technology. Rats harboring either mutation type lacked expressionmore » of AHR protein in the liver. AHR-KO rats were also insensitive to thymic involution, increased hepatic weight and the induction of AHR-responsive genes (Cyp1a1, Cyp1a2, Cyp1b1, Ahrr) following acute exposure to 25 μg/kg TCDD. AHR-KO rats had lower basal expression of transcripts for these genes and also accumulated ∼ 30–45-fold less TCDD in the liver at 7 days post-exposure. In untreated animals, AHR-KO mice, but not AHR-KO rats, had alterations in serum analytes indicative of compromised hepatic function, patent ductus venosus of the liver and persistent hyaloid arteries in the eye. AHR-KO rats, but not AHR-KO mice, displayed pathological alterations to the urinary tract: bilateral renal dilation (hydronephrosis), secondary medullary tubular and uroepithelial degenerative changes and bilateral ureter dilation (hydroureter). The present data indicate that the AHR may play significantly different roles in tissue development and homeostasis and toxicity across rodent species. - Highlights: • An AHR knockout rat was generated on a Sprague–Dawley outbred background. • AHR-KO rats lack expression of AHR protein. • AHR-KO rats are insensitive to TCDD-mediated effects. • Data suggests difference in the role of AHR in tissue development of rats and mice. • Abnormalities in

  20. Lack of neuronal nitric oxide synthase results in attention deficit / hyperactivity disorder – like behaviors in mice

    PubMed Central

    Gao, Yudong; Heldt, Scott A.

    2015-01-01

    Nitric oxide (NO) is an important molecule for the proper development and function of the central nervous system. In this study, we investigated the behavioral alterations in the neuronal nitric oxide synthase knockout mice (NOS1 KO) with a deficient NO production mechanism in the brain, characterizing it as a potential rodent model for attention deficit / hyperactivity disorder (ADHD). NOS1 KO exhibited higher locomotor activity than their wildtype counterparts in a novel environment, as measured by open field (OF) test. In a two-way active avoidance paradigm (TWAA), we found sex-dependent effects, where male KO displayed deficits in avoidance and escape behavior, sustained higher incidences of shuttle crossings and higher incidences of inter-trial interval crossings, suggesting learning and/or performance impairments. On the other hand, female KO demonstrated few deficits in TWAA. Molsidomine (MSD), a NO donor, rescued TWAA deficits in male KO when acutely administered before training. In a passive avoidance paradigm, KO of both sexes displayed significantly shorter step-through latencies after training. Further, abnormal spontaneous motor activity rhythms were found in the KO during the dark phase of the day, indicating dysregulation of rhythmic activities. These data indicate that NOS1 KO mimic certain ADHD-like behaviors and could potentially serve as a novel rodent model for ADHD. PMID:25621792

  1. Male mice with deleted Wolframin (Wfs1) gene have reduced fertility.

    PubMed

    Noormets, Klari; Kõks, Sulev; Kavak, Ants; Arend, Andres; Aunapuu, Marina; Keldrimaa, Aivi; Vasar, Eero; Tillmann, Vallo

    2009-08-10

    Wolfram Syndrome (WS) is an autosomal recessive disorder characterised by non-autoimmune diabetes mellitus, optic atrophy, cranial diabetes insipidus and sensorineural deafness. Some reports have described hypogonadism in male WS patients. The aim of our study was to find out whether Wfs1 deficient (Wfs1KO) male mice have reduced fertility and, if so, to examine possible causes. Wfs1KO mice were generated by homologous recombination. Both Wfs1KO and wild type (wt) male mice were mated with wt female mice. The number of litters and the number of pups were counted and pregnancy rates calculated. The motility and morphology of the sperm and the histology of testes were analysed. Serum testosterone and FSH concentrations were also measured. The pregnancy rate in wt females mated with Wfs1KO males was significantly lower than in the control group (15% vs. 32%; p < 0.05), but there was no significant difference in litter size. Analysis of male fertility showed that, in the Wfs1KO group, eight males out of 13 had pups whereas in the control group all 13 males had at least one litter. Sperm motility was not affected in Wfs1KO mice, but Wfs1KO males had less proximal bent tails (14.4 +/- 1.2% vs. 21.5 +/- 1.3 p < 0.05) and less abnormal sperm heads (22.8 +/- 1.8 vs. 31.5 +/- 3.5, p < 0.05) than wt males. Testes histology revealed significantly reduced number of spermatogonia (23.9 +/- 4.9 vs. 38.1 +/- 2.8; p < 0.05) and Sertoli cells (6.4 +/- 0.5 vs. 9.2 +/- 1.0; p < 0.05) in Wfs1KO mice. Serum testosterone and FSH concentrations did not differ between the two groups. The impaired fertility of Wfs1KO male mice is most likely due to changes in sperm morphology and reduced number of spermatogenic cells. The exact mechanism through which the Wfs1 gene influences sperm morphology needs to be clarified in further studies.

  2. Male mice with deleted Wolframin (Wfs1) gene have reduced fertility

    PubMed Central

    Noormets, Klari; Kõks, Sulev; Kavak, Ants; Arend, Andres; Aunapuu, Marina; Keldrimaa, Aivi; Vasar, Eero; Tillmann, Vallo

    2009-01-01

    Background Wolfram Syndrome (WS) is an autosomal recessive disorder characterised by non-autoimmune diabetes mellitus, optic atrophy, cranial diabetes insipidus and sensorineural deafness. Some reports have described hypogonadism in male WS patients. The aim of our study was to find out whether Wfs1 deficient (Wfs1KO) male mice have reduced fertility and, if so, to examine possible causes. Methods Wfs1KO mice were generated by homologous recombination. Both Wfs1KO and wild type (wt) male mice were mated with wt female mice. The number of litters and the number of pups were counted and pregnancy rates calculated. The motility and morphology of the sperm and the histology of testes were analysed. Serum testosterone and FSH concentrations were also measured. Results The pregnancy rate in wt females mated with Wfs1KO males was significantly lower than in the control group (15% vs. 32%; p < 0.05), but there was no significant difference in litter size. Analysis of male fertility showed that, in the Wfs1KO group, eight males out of 13 had pups whereas in the control group all 13 males had at least one litter. Sperm motility was not affected in Wfs1KO mice, but Wfs1KO males had less proximal bent tails (14.4 +/- 1.2% vs. 21.5 +/- 1.3 p < 0.05) and less abnormal sperm heads (22.8 +/- 1.8 vs. 31.5 +/- 3.5, p < 0.05) than wt males. Testes histology revealed significantly reduced number of spermatogonia (23.9 +/- 4.9 vs. 38.1 +/- 2.8; p < 0.05) and Sertoli cells (6.4 +/- 0.5 vs. 9.2 +/- 1.0; p < 0.05) in Wfs1KO mice. Serum testosterone and FSH concentrations did not differ between the two groups. Conclusion The impaired fertility of Wfs1KO male mice is most likely due to changes in sperm morphology and reduced number of spermatogenic cells. The exact mechanism through which the Wfs1 gene influences sperm morphology needs to be clarified in further studies. PMID:19664290

  3. KoBaMIN: a knowledge-based minimization web server for protein structure refinement.

    PubMed

    Rodrigues, João P G L M; Levitt, Michael; Chopra, Gaurav

    2012-07-01

    The KoBaMIN web server provides an online interface to a simple, consistent and computationally efficient protein structure refinement protocol based on minimization of a knowledge-based potential of mean force. The server can be used to refine either a single protein structure or an ensemble of proteins starting from their unrefined coordinates in PDB format. The refinement method is particularly fast and accurate due to the underlying knowledge-based potential derived from structures deposited in the PDB; as such, the energy function implicitly includes the effects of solvent and the crystal environment. Our server allows for an optional but recommended step that optimizes stereochemistry using the MESHI software. The KoBaMIN server also allows comparison of the refined structures with a provided reference structure to assess the changes brought about by the refinement protocol. The performance of KoBaMIN has been benchmarked widely on a large set of decoys, all models generated at the seventh worldwide experiments on critical assessment of techniques for protein structure prediction (CASP7) and it was also shown to produce top-ranking predictions in the refinement category at both CASP8 and CASP9, yielding consistently good results across a broad range of model quality values. The web server is fully functional and freely available at http://csb.stanford.edu/kobamin.

  4. Iron Homeostasis and Inflammatory Status in Mice Deficient for the Cystic Fibrosis Transmembrane Regulator.

    PubMed

    Deschemin, Jean-Christophe; Allouche, Sarah; Brouillard, Franck; Vaulont, Sophie

    2015-01-01

    Cystic Fibrosis (CF) is a frequent and lethal autosomal recessive disease caused by mutations in the gene encoding the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). Patients with CF suffer from chronic infections and severe inflammation, which lead to progressive pulmonary and gut diseases. Recently, an expanding body of evidence has suggested that iron homeostasis was abnormal in CF with, in particular, systemic iron deficiency and iron sequestration in the epithelium airway. The molecular mechanisms responsible for iron dysregulation and the relationship with inflammation in CF are unknown. We assessed the impact of CFTR deficiency on systemic and tissue iron homeostasis as well as inflammation in wildtype and CFTR knockout (KO) mice. First, in contrast to the systemic and intestinal inflammation we observed in the CFTR KO mice, we reported the absence of lung phenotype with regards to both inflammation and iron status. Second, we showed a significant decrease of plasma ferritin levels in the KO mice, as in CF patients, likely caused by a decrease in spleen ferritin levels. However, we measured unchanged plasma iron levels in the KO mice that may be explained by increased intestinal iron absorption. These results indicate that in CF, the lung do not predominantly contributes to the systemic ferritin deficiency and we propose the spleen as the major organ responsible for hypoferritinemia in the KO mouse. These results should provide a better understanding of iron dysregulation in CF patients where treating or not iron deficiency remains a challenging question.

  5. Knockout mice reveal a role for protein tyrosine phosphatase H1 in cognition.

    PubMed

    Patrignani, Claudia; Magnone, Maria Chiara; Tavano, Patrizia; Ardizzone, Michele; Muzio, Valeria; Gréco, Béatrice; Zaratin, Paola F

    2008-08-12

    The present study has investigated the protein tyrosine phosphatase H1 (PTPH1) expression pattern in mouse brain and its impact on CNS functions. We have previously described a PTPH1-KO mouse, generated by replacing the PTP catalytic and the PDZ domain with a LacZ neomycin cassette. PTPH1 expression pattern was evaluated by LacZ staining in the brain and PTPH1-KO and WT mice (n = 10 per gender per genotype) were also behaviorally tested for CNS functions. In CNS, PTPH1 is expressed during development and in adulthood and mainly localized in hippocampus, thalamus, cortex and cerebellum neurons. The behavioral tests performed on the PTPH1-KO mice showed an impact on working memory in male mice and an impaired learning performance at rotarod in females. These results demonstrate for the first time a neuronal expression of PTPH1 and its functionality at the level of cognition.

  6. Ablation of Promyelocytic Leukemia Protein (PML) Re-patterns Energy Balance and Protects Mice from Obesity Induced by a Western Diet*

    PubMed Central

    Cheng, Xiwen; Guo, Shuang; Liu, Yu; Chu, Hao; Hakimi, Parvin; Berger, Nathan A.; Hanson, Richard W.; Kao, Hung-Ying

    2013-01-01

    The promyelocytic leukemia protein is a well known tumor suppressor, but its role in metabolism is largely unknown. Mice with a deletion in the gene for PML (KO mice) exhibit altered gene expression in liver, adipose tissue, and skeletal muscle, an accelerated rate of fatty acid metabolism, abnormal glucose metabolism, constitutive AMP-activating kinase (AMPK) activation, and insulin resistance in skeletal muscle. Last, an increased rate of energy expenditure protects PML KO mice from the effects of obesity induced by a Western diet. Collectively, our study uncovers a previously unappreciated role of PML in the regulation of metabolism and energy balance in mice. PMID:23986437

  7. Successful adaptation to ketosis by mice with tissue-specific deficiency of ketone body oxidation

    PubMed Central

    Cotter, David G.; Schugar, Rebecca C.; Wentz, Anna E.; André d'Avignon, D.

    2013-01-01

    During states of low carbohydrate intake, mammalian ketone body metabolism transfers energy substrates originally derived from fatty acyl chains within the liver to extrahepatic organs. We previously demonstrated that the mitochondrial enzyme coenzyme A (CoA) transferase [succinyl-CoA:3-oxoacid CoA transferase (SCOT), encoded by nuclear Oxct1] is required for oxidation of ketone bodies and that germline SCOT-knockout (KO) mice die within 48 h of birth because of hyperketonemic hypoglycemia. Here, we use novel transgenic and tissue-specific SCOT-KO mice to demonstrate that ketone bodies do not serve an obligate energetic role within highly ketolytic tissues during the ketogenic neonatal period or during starvation in the adult. Although transgene-mediated restoration of myocardial CoA transferase in germline SCOT-KO mice is insufficient to prevent lethal hyperketonemic hypoglycemia in the neonatal period, mice lacking CoA transferase selectively within neurons, cardiomyocytes, or skeletal myocytes are all viable as neonates. Like germline SCOT-KO neonatal mice, neonatal mice with neuronal CoA transferase deficiency exhibit increased cerebral glycolysis and glucose oxidation, and, while these neonatal mice exhibit modest hyperketonemia, they do not develop hypoglycemia. As adults, tissue-specific SCOT-KO mice tolerate starvation, exhibiting only modestly increased hyperketonemia. Finally, metabolic analysis of adult germline Oxct1+/− mice demonstrates that global diminution of ketone body oxidation yields hyperketonemia, but hypoglycemia emerges only during a protracted state of low carbohydrate intake. Together, these data suggest that, at the tissue level, ketone bodies are not a required energy substrate in the newborn period or during starvation, but rather that integrated ketone body metabolism mediates adaptation to ketogenic nutrient states. PMID:23233542

  8. KoFlux: Korean Regional Flux Network in AsiaFlux

    NASA Astrophysics Data System (ADS)

    Kim, J.

    2002-12-01

    AsiaFlux, the Asian arm of FLUXNET, held the Second International Workshop on Advanced Flux Network and Flux Evaluation in Jeju Island, Korea on 9-11 January 2002. In order to facilitate comprehensive Asia-wide studies of ecosystem fluxes, the meeting launched KoFlux, a new Korean regional network of long-term micrometeorological flux sites. For a successful assessment of carbon exchange between terrestrial ecosystems and the atmosphere, an accurate measurement of surface fluxes of energy and water is one of the prerequisites. During the 7th Global Energy and Water Cycle Experiment (GEWEX) Asian Monsoon Experiment (GAME) held in Nagoya, Japan on 1-2 October 2001, the Implementation Committee of the Coordinated Enhanced Observing Period (CEOP) was established. One of the immediate tasks of CEOP was and is to identify the reference sites to monitor energy and water fluxes over the Asian continent. Subsequently, to advance the regional and global network of these reference sites in the context of both FLUXNET and CEOP, the Korean flux community has re-organized the available resources to establish a new regional network, KoFlux. We have built up domestic network sites (equipped with wind profiler and radiosonde measurements) over deciduous and coniferous forests, urban and rural rice paddies and coastal farmland. As an outreach through collaborations with research groups in Japan, China and Thailand, we also proposed international flux sites at ecologically and climatologically important locations such as a prairie on the Tibetan plateau, tropical forest with mixed and rapid land use change in northern Thailand. Several sites in KoFlux already begun to accumulate interesting data and some highlights are presented at the meeting. The sciences generated by flux networks in other continents have proven the worthiness of a global array of micrometeorological flux towers. It is our intent that the launch of KoFlux would encourage other scientists to initiate and

  9. Excitability is increased in hippocampal CA1 pyramidal cells of Fmr1 knockout mice

    PubMed Central

    Luque, M. Angeles; Beltran-Matas, Pablo; Marin, M. Carmen; Torres, Blas

    2017-01-01

    Fragile X syndrome (FXS) is caused by a failure of neuronal cells to express the gene encoding the fragile mental retardation protein (FMRP). Clinical features of the syndrome include intellectual disability, learning impairment, hyperactivity, seizures and anxiety. Fmr1 knockout (KO) mice do not express FMRP and, as a result, reproduce some FXS behavioral abnormalities. While intrinsic and synaptic properties of excitatory cells in various part of the brain have been studied in Fmr1 KO mice, a thorough analysis of action potential characteristics and input-output function of CA1 pyramidal cells in this model is lacking. With a view to determining the effects of the absence of FMRP on cell excitability, we studied rheobase, action potential duration, firing frequency–current intensity relationship and action potential after-hyperpolarization (AHP) in CA1 pyramidal cells of the hippocampus of wild type (WT) and Fmr1 KO male mice. Brain slices were prepared from 8- to 12-week-old mice and the electrophysiological properties of cells recorded. Cells from both groups had similar resting membrane potentials. In the absence of FMRP expression, cells had a significantly higher input resistance, while voltage threshold and depolarization voltage were similar in WT and Fmr1 KO cell groups. No changes were observed in rheobase. The action potential duration was longer in the Fmr1 KO cell group, and the action potential firing frequency evoked by current steps of the same intensity was higher. Moreover, the gain (slope) of the relationship between firing frequency and injected current was 1.25-fold higher in the Fmr1 KO cell group. Finally, AHP amplitude was significantly reduced in the Fmr1 KO cell group. According to these data, FMRP absence increases excitability in hippocampal CA1 pyramidal cells. PMID:28931075

  10. Mechanism of Hyperphagia Contributing to Obesity in Brain-Derived Neurotrophic Factor Knockout Mice

    PubMed Central

    Fox, Edward A.; Biddinger, Jessica E.; Jones, Kevin R.; McAdams, Jennifer; Worman, Amber

    2012-01-01

    Global-heterozygous and brain-specific homozygous knockouts (KO's) of brain-derived neurotrophic factor (BDNF) cause late- and early-onset obesity, respectively, both involving hyperphagia. Little is known about the mechanism underlying this hyperphagia or whether BDNF loss from peripheral tissues could contribute to overeating. Since global-homozygous BDNF-KO is perinatal lethal, a BDNF-KO that spared sufficient brainstem BDNF to support normal health was utilized to begin to address these issues. Meal pattern and microstructure analyses suggested overeating of BDNF-KO mice was mediated by deficits in both satiation and satiety that resulted in increased meal size and frequency and implicated a reduction of vagal signaling from gut-to-brain. Meal-induced c-Fos activation in the nucleus of the solitary tract, a more direct measure of vagal afferent signaling, however, was not decreased in BDNF-KO mice, and thus was not consistent with a vagal afferent role. Interestingly though, meal-induced c-Fos activation was increased in the dorsal vagal motor nucleus (DMV) of BDNF-KO mice. This could imply that augmentation of vago-vagal digestive reflexes occurred (e.g., accommodation), which would support increased meal size and possibly increased meal number by reducing the increase in intragastric pressure produced by a given amount of ingesta. Additionally, vagal sensory neuron number in BDNF-KO mice was altered in a manner consistent with the increased meal-induced activation of the DMV. These results suggest reduced BDNF causes satiety and satiation deficits that support hyperphagia, possibly involving augmentation of vago-vagal reflexes mediated by central pathways or vagal afferents regulated by BDNF levels. PMID:23069761

  11. In vivo rescue of alveolar macrophages from SP-A knockout mice with exogenous SP-A nearly restores a wild type intracellular proteome; actin involvement

    PubMed Central

    2011-01-01

    Background Mice lacking surfactant protein-A (SP-A-/-; knockout; KO) exhibit increased vulnerability to infection and injury. Although many bronchoalveolar lavage (BAL) protein differences between KO and wild-type (WT) are rapidly reversed in KO after infection, their clinical course is still compromised. We studied the impact of SP-A on the alveolar macrophage (AM) proteome under basal conditions. Male SP-A KO mice were SP-A-treated (5 micrograms/mouse) and sacrificed in 6 or 18 hr. The AM proteomes of KO, SP-A-treated KO, and WT mice were studied by 2D-DIGE coupled with MALDI-ToF/ToF and AM actin distribution was examined by phalloidon staining. Results We observed: a) significant differences from KO in WT or exogenous SP-A-treated in 45 of 76 identified proteins (both increases and decreases). These included actin-related/cytoskeletal proteins (involved in motility, phagocytosis, endocytosis), proteins of intracellular signaling, cell differentiation/regulation, regulation of inflammation, protease/chaperone function, and proteins related to Nrf2-mediated oxidative stress response pathway; b) SP-A-induced changes causing the AM proteome of the KO to resemble that of WT; and c) that SP-A treatment altered cell size and F-actin distribution. Conclusions These differences are likely to enhance AM function. The observations show for the first time that acute in vivo SP-A treatment of KO mice, under basal or unstimulated conditions, affects the expression of multiple AM proteins, alters F-actin distribution, and can restore much of the WT phenotype. We postulate that the SP-A-mediated expression profile of the AM places it in a state of "readiness" to successfully conduct its innate immune functions and ensure lung health. PMID:22035134

  12. Altered gene expression in early postnatal monoamine oxidase A knockout mice.

    PubMed

    Chen, Kevin; Kardys, Abbey; Chen, Yibu; Flink, Stephen; Tabakoff, Boris; Shih, Jean C

    2017-08-15

    We reported previously that monoamine oxidase (MAO) A knockout (KO) mice show increased serotonin (5-hydroxytryptamine, 5-HT) levels and autistic-like behaviors characterized by repetitive behaviors, and anti-social behaviors. We showed that administration of the serotonin synthesis inhibitor para-chlorophenylalanine (pCPA) from post-natal day 1 (P1) through 7 (P7) in MAO A KO mice reduced the serotonin level to normal and reverses the repetitive behavior. These results suggested that the altered gene expression at P1 and P7 may be important for the autistic-like behaviors seen in MAO A KO mice and was studied here. In this study, Affymetrix mRNA array data for P1 and P7 MAO A KO mice were analyzed using Partek Genomics Suite and Ingenuity Pathways Analysis to identify genes differentially expressed versus wild-type and assess their functions and relationships. The number of significant differentially expressed genes (DEGs) varied with age: P1 (664) and P7 (3307) [false discovery rate (FDR) <0.05, fold-change (FC) >1.5 for autism-linked genes and >2.0 for functionally categorized genes]. Eight autism-linked genes were differentially expressed in P1 (upregulated: NLGN3, SLC6A2; down-regulated: HTR2C, MET, ADSL, MECP2, ALDH5A1, GRIN3B) while four autism-linked genes were differentially expressed at P7 (upregulated: HTR2B; downregulated: GRIN2D, GRIN2B, CHRNA4). Many other genes involved in neurodevelopment, apoptosis, neurotransmission, and cognitive function were differentially expressed at P7 in MAO A KO mice. This result suggests that modulation of these genes by the increased serotonin may lead to neurodevelopmental alteration in MAO A KO mice and results in autistic-like behaviors. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Increased anxiety and fear memory in adult mice lacking type 2 deiodinase.

    PubMed

    Bárez-López, Soledad; Montero-Pedrazuela, Ana; Bosch-García, Daniel; Venero, César; Guadaño-Ferraz, Ana

    2017-10-01

    A euthyroid state in the brain is crucial for its adequate development and function. Impairments in thyroid hormones (THs; T3 or 3,5,3'-triiodothyronine and T4 or thyroxine) levels and availability in brain can lead to neurological alterations and to psychiatric disorders, particularly mood disorders. The thyroid gland synthetizes mainly T4, which is secreted to circulating blood, however, most actions of THs are mediated by T3, the transcriptionally active form. In the brain, intracellular concentrations of T3 are modulated by the activity of type 2 (D2) and type 3 (D3) deiodinases. In the present work, we evaluated learning and memory capabilities and anxiety-like behavior at adult stages in mice lacking D2 (D2KO) and we analyzed the impact of D2-deficiency on TH content and on the expression of T3-dependent genes in the amygdala and the hippocampus. We found that D2KO mice do not present impairments in spatial learning and memory, but they display emotional alterations with increased anxiety-like behavior as well as enhanced auditory-cued fear memory and spontaneous recovery of fear memory following extinction. D2KO mice also presented reduced T3 content in the hippocampus and decreased expression of the T3-dependent gene Dio3 in the amygdala suggesting a hypothyroid status in this structure. We propose that the emotional dysfunctions found in D2KO mice can arise from the reduced T3 content in their brain, which consequently leads to alterations in gene expression with functional consequences. We found a downregulation in the gene encoding for the calcium-binding protein calretinin (Calb2) in the amygdala of D2KO mice that could affect the GABAergic transmission. The current findings in D2KO mice can provide insight into emotional disorders present in humans with DIO2 polymorphisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Organelle and Cellular Abnormalities Associated with Hippocampal Heterotopia in Neonatal Doublecortin Knockout Mice

    PubMed Central

    Khalaf-Nazzal, Reham; Bruel-Jungerman, Elodie; Rio, Jean-Paul; Bureau, Jocelyne; Irinopoulou, Theano; Sumia, Iffat; Roumegous, Audrey; Martin, Elodie; Olaso, Robert; Parras, Carlos; Cifuentes-Diaz, Carmen; Francis, Fiona

    2013-01-01

    Heterotopic or aberrantly positioned cortical neurons are associated with epilepsy and intellectual disability. Various mouse models exist with forms of heterotopia, but the composition and state of cells developing in heterotopic bands has been little studied. Dcx knockout (KO) mice show hippocampal CA3 pyramidal cell lamination abnormalities, appearing from the age of E17.5, and mice suffer from spontaneous epilepsy. The Dcx KO CA3 region is organized in two distinct pyramidal cell layers, resembling a heterotopic situation, and exhibits hyperexcitability. Here, we characterized the abnormally organized cells in postnatal mouse brains. Electron microscopy confirmed that the Dcx KO CA3 layers at postnatal day (P) 0 are distinct and separated by an intermediate layer devoid of neuronal somata. We found that organization and cytoplasm content of pyramidal neurons in each layer were altered compared to wild type (WT) cells. Less regular nuclei and differences in mitochondria and Golgi apparatuses were identified. Each Dcx KO CA3 layer at P0 contained pyramidal neurons but also other closely apposed cells, displaying different morphologies. Quantitative PCR and immunodetections revealed increased numbers of oligodendrocyte precursor cells (OPCs) and interneurons in close proximity to Dcx KO pyramidal cells. Immunohistochemistry experiments also showed that caspase-3 dependent cell death was increased in the CA1 and CA3 regions of Dcx KO hippocampi at P2. Thus, unsuspected ultrastructural abnormalities and cellular heterogeneity may lead to abnormal neuronal function and survival in this model, which together may contribute to the development of hyperexcitability. PMID:24023755

  15. Arginase II Deletion Increases Corpora Cavernosa Relaxation in Diabetic Mice

    PubMed Central

    Toque, Haroldo; Tostes, Rita; Yao, Lin; Xu, Zhimin; Webb, Clinton R.; Caldwell, Ruth; Caldwell, Robert

    2010-01-01

    Introduction Diabetes-induced erectile dysfunction involves elevated arginase (Arg) activity and expression. Because nitric oxide (NO) synthase and Arg share and compete for their substrate L-arginine, NO production is likely linked to regulation of Arg. Arg is highly expressed and implicated in erectile dysfunction. Aim It was hypothesized that Arg-II isoform deletion enhances relaxation function of corpora cavernosal (CC) smooth muscle in a streptozotocin (STZ) diabetic model. Methods Eight weeks after STZ-induced diabetes, vascular functional studies, Arg activity assay, and protein expression levels of Arg and constitutive NOS (using western blots) were assessed in CC tissues from non-diabetic wild type (WT), diabetic (D) WT (WT+D), Arg-II knockout (KO) and Arg-II KO+D mice (N=8–10 per group). Main Outcome Measures Inhibition or lack of arginase results in facilitation of CC relaxation in diabetic CC. Results Strips of CC from Arg-II KO mice exhibited an enhanced maximum endothelium-dependent relaxation (from 70+3% to 84+4%) and increased nitrergic relaxation (by 55%, 71%, 42%, 42%, and 24% for 1, 2, 4, 8 and 16 Hz, respectively) compared to WT mice. WT+D mice showed a significant reduction of endothelium-dependent maximum relaxation (44+8%), but this impairment of relaxation was significantly prevented in Arg-II KO+D mice (69+4%). Sympathetic-mediated and alpha-adrenergic agent-induced contractile responses also were increased in CC strips from D compared to non-D controls. Contractile responses were significantly lower in Arg-II KO control and D versus the WT groups. WT+D mice increased Arg activity (1.5-fold) and Arg-II protein expression and decreased total and phospho-eNOS at Ser-1177, and nNOS levels. These alterations were not seen in Arg-II KO mice. Additionally, the Arg inhibitor BEC (50 μM) enhanced nitrergic and endothelium-dependent relaxation in CC of WT+D mice. Conclusion These studies show for the first time that Arg-II deletion improves CC

  16. Role of surfactant protein-A (SP-A) in lung injury in response to acute ozone exposure of SP-A deficient mice

    SciTech Connect

    Haque, Rizwanul; Umstead, Todd M.; Ponnuru, Padmavathi

    2007-04-01

    Millions are exposed to ozone levels above recommended limits, impairing lung function, causing epithelial damage and inflammation, and predisposing some individuals to pneumonia, asthma, and other lung conditions. Surfactant protein-A (SP-A) plays a role in host defense, the regulation of inflammation, and repair of tissue damage. We tested the hypothesis that the lungs of SP-A(-/-) (KO) mice are more susceptible to ozone-induced damage. We compared the effects of ozone on KO and wild type (WT) mice on the C57BL/6 genetic background by exposing them to 2 parts/million of ozone for 3 or 6 h and sacrificing them 0, 4, andmore » 24 h later. Lungs were subject to bronchoalveolar lavage (BAL) or used to measure endpoints of oxidative stress and inflammation. Despite more total protein in BAL of KO mice after a 3 h ozone exposure, WT mice had increased oxidation of protein and had oxidized SP-A dimers. In KO mice there was epithelial damage as assessed by increased LDH activity and there was increased phospholipid content. In WT mice there were more BAL PMNs and elevated macrophage inflammatory protein (MIP)-2 and monocyte chemoattractant protein (MCP)-1. Changes in MIP-2 and MCP-1 were observed in both KO and WT, however mRNA levels differed. In KO mice MIP-2 mRNA levels changed little with ozone, but in WT levels they were significantly increased. In summary, several aspects of the inflammatory response differ between WT and KO mice. These in vivo findings appear to implicate SP-A in regulating inflammation and limiting epithelial damage in response to ozone exposure.« less

  17. Effects of Nrf2 deficiency on arsenic metabolism in mice.

    PubMed

    Wang, Huihui; Zhu, Jiayu; Li, Lu; Li, Yongfang; Lv, Hang; Xu, Yuanyuan; Sun, Guifan; Pi, Jingbo

    2017-12-15

    Inorganic arsenic (iAs) is a known toxicant and carcinogen. Worldwide arsenic exposure has become a threat to human health. The severity of arsenic toxicity is strongly correlated with the speed of arsenic metabolism (methylation) and clearance. Furthermore, oxidative stress is recognized as a major mechanism for arsenic-induced toxicity. Nuclear factor-E2-related factor 2 (Nrf2), a key regulator in cellular adaptive antioxidant response, is clearly involved in alleviation of arsenic-induced oxidative damage. Multiple studies demonstrate that Nrf2 deficiency mice are more vulnerable to arsenic-induced intoxication. However, what effect Nrf2 deficiency might have on arsenic metabolism in mice is still unknown. In the present study, we measured the key enzymes involved in arsenic metabolism in Nrf2-WT and Nrf2-KO mice. Our results showed that basal transcript levels of glutathione S-transferase omega 2 (Gsto2) were significantly higher and GST mu 1 (Gstm1) lower in Nrf2-KO mice compared to Nrf2-WT control. Arsenic speciation and methylation rate in liver and urine was then studied in mice treated with 5mg/kg sodium arsenite for 12h. Although there were some alterations in arsenic metabolism enzymes between Nrf2-WT and Nrf2-KO mice, the Nrf2 deficiency had no significant effect on arsenic methylation. These results suggest that the Nrf2-KO mice are more sensitive to arsenic than Nrf2-WT mainly because of differences in adaptive antioxidant detoxification capacity rather than arsenic methylation capacity. Copyright © 2017. Published by Elsevier Inc.

  18. Cluster and principal component analysis based on SSR markers of Amomum tsao-ko in Jinping County of Yunnan Province

    NASA Astrophysics Data System (ADS)

    Ma, Mengli; Lei, En; Meng, Hengling; Wang, Tiantao; Xie, Linyan; Shen, Dong; Xianwang, Zhou; Lu, Bingyue

    2017-08-01

    Amomum tsao-ko is a commercial plant that used for various purposes in medicinal and food industries. For the present investigation, 44 germplasm samples were collected from Jinping County of Yunnan Province. Clusters analysis and 2-dimensional principal component analysis (PCA) was used to represent the genetic relations among Amomum tsao-ko by using simple sequence repeat (SSR) markers. Clustering analysis clearly distinguished the samples groups. Two major clusters were formed; first (Cluster I) consisted of 34 individuals, the second (Cluster II) consisted of 10 individuals, Cluster I as the main group contained multiple sub-clusters. PCA also showed 2 groups: PCA Group 1 included 29 individuals, PCA Group 2 included 12 individuals, consistent with the results of cluster analysis. The purpose of the present investigation was to provide information on genetic relationship of Amomum tsao-ko germplasm resources in main producing areas, also provide a theoretical basis for the protection and utilization of Amomum tsao-ko resources.

  19. Effects of Hint1 deficiency on emotional-like behaviors in mice under chronic immobilization stress.

    PubMed

    Sun, Liankang; Liu, Peng; Liu, Fei; Zhou, Yuan; Chu, Zheng; Li, Yuqi; Chu, Guang; Zhang, Ying; Wang, Jiabei; Dang, Yong-Hui

    2017-10-01

    Histidine triad nucleotide-binding protein 1 (HINT1) is regarded as a haplo-insufficient tumor suppressor and is closely associated with diverse neuropsychiatric diseases. Moreover, HINT1 is related to gender-specific acute behavior changes in schizophrenia and in response to nicotine. Stress has a range of molecular effects in emotional disorders, which can cause a reduction in brain-derived neurotrophic factor (BDNF) expression in the hippocampus, resulting in hippocampal atrophy and neuronal cell loss. This study examined the role of HINT1 deficiency in anxiety-related and depression-like behaviors and BDNF expression in the hippocampus under chronic immobilization stress, and investigated whether the sex-specific and haplo-insufficient effects exist in emotional-like behaviors under the same condition. In a battery of behavior tests, the results of the control group, not exposed to stress, showed that knockout (KO) and heterozygosity (HT) of Hint1 had anxiolytic-like and antidepression-like effects on the male and female mice. However, both male and female Hint1 -KO mice showed elevated anxiety-related and antidepression-like behavior under chronic immobilization stress; moreover, both male and female Hint1 -HT mice displayed elevated anxiety-related behavior and increased depression-like behavior under chronic immobilization stress. There were no significant differences in general locomotor activity between Hint1 -KO and -HT mice and their wild-type (WT) littermates. Hint1 -KO mice under basal and chronic immobilization stress conditions expressed more BDNF in the hippocampus than did Hint1 -HT and WT mice; overall, there were no significant sex differences in emotional-like behaviors of Hint1 -KO and -HT mice. Additionally, Hint1-HT mice showed haplo-insufficient effects on emotional-like behaviors under basic conditions, rather than under chronic immobilization stress. Both male and female HINT 1 KO and HT mice had a trend of anxiolytic-like behavior and

  20. Augmentation of methamphetamine-induced behaviors in transgenic mice lacking the trace amine-associated receptor 1

    PubMed Central

    Achat-Mendes, Cindy; Lynch, Laurie J.; Sullivan, Katherine A.; Vallender, Eric J.; Miller, Gregory M.

    2011-01-01

    The trace amine-associated receptor 1 (TAAR1) is a G protein-coupled receptor that is functionally activated by amphetamine-based psychostimulants, including amphetamine, methamphetamine and MDMA. Previous studies have shown that in transgenic mice lacking the TAAR1 gene (TAAR1 knockout; KO) a single injection of amphetamine can produce enhanced behavioral responses compared to responses evoked in wild-type (WT) mice. Further, the psychostimulant effects of cocaine can be diminished by selective activation of TAAR1. These findings suggest that TAAR1 might be implicated in the rewarding properties of psychostimulants. To investigate the role of TAAR1 in the rewarding effects of drugs of abuse, the psychomotor stimulating effects of amphetamine and methamphetamine and the conditioned rewarding effects of methamphetamine and morphine were compared between WT and TAAR1 KO mice. In locomotor activity studies, both single and repeated exposure to d-amphetamine or methamphetamine generated significantly higher levels of total distance travelled in TAAR1 KO mice compared to WT mice. In conditioned place preference (CPP) studies, TAAR1 KO mice acquired methamphetamine-induced CPP earlier than WT mice and retained CPP longer during extinction training. In orphine-induced CPP, both WT and KO genotypes displayed similar levels of CPP. Results from locomotor activity studies suggest that TAAR1 may have a modulatory role in the behavioral sensitization to amphetamine-based psychostimulants. That methamphetamine- but not morphine-induced CPP was augmented in TAAR1 KO mice suggests a selective role of TAAR1 in the conditioned reinforcing effects of methamphetamine. Collectively, these findings provide support for a regulatory role of TAAR1 in methamphetamine signaling. PMID:22079347

  1. Salt-Sensitive Hypertension and Cardiac Hypertrophy in Transgenic Mice Expressing a Corin Variant Identified in African Americans

    PubMed Central

    Wang, Wei; Cui, Yujie; Shen, Jianzhong; Jiang, Jingjing; Chen, Shenghan; Peng, Jianhao; Wu, Qingyu

    2012-01-01

    African Americans represent a high risk population for salt-sensitive hypertension and heart disease but the underlying mechanism remains unclear. Corin is a cardiac protease that regulates blood pressure by activating natriuretic peptides. A corin gene variant (T555I/Q568P) was identified in African Americans with hypertension and cardiac hypertrophy. In this study, we test the hypothesis that the corin variant contributes to the hypertensive and cardiac hypertrophic phenotype in vivo. Transgenic mice were generated to express wild-type or T555I/Q568P variant corin in the heart under the control of α-myosin heavy chain promoter. The mice were crossed into a corin knockout background to create KO/TgWT and KO/TgV mice that expressed WT or variant corin, respectively, in the heart. Functional studies showed that KO/TgV mice had significantly higher levels of pro-atrial natriuretic peptide in the heart compared with that in control KO/TgWT mice, indicating that the corin variant was defective in processing natriuretic peptides in vivo. By radiotelemetry, corin KO/TgV mice were found to have hypertension that was sensitive to dietary salt loading. The mice also developed cardiac hypertrophy at 12–14 months of age when fed a normal salt diet or at a younger age when fed a high salt diet. The phenotype of salt-sensitive hypertension and cardiac hypertrophy in KO/TgV mice closely resembles the pathological findings in African Americans who carry the corin variant. The results indicate that corin defects may represent an important mechanism in salt-sensitive hypertension and cardiac hypertrophy in African Americans. PMID:22987923

  2. p21{sup WAF1/Cip1/Sdi1} knockout mice respond to doxorubicin with reduced cardiotoxicity

    SciTech Connect

    Terrand, Jerome; Xu, Beibei; Morrissy, Steve

    2011-11-15

    Doxorubicin (Dox) is an antineoplastic agent that can cause cardiomyopathy in humans and experimental animals. As an inducer of reactive oxygen species and a DNA damaging agent, Dox causes elevated expression of p21{sup WAF1/Cip1/Sdi1} (p21) gene. Elevated levels of p21 mRNA and p21 protein have been detected in the myocardium of mice following Dox treatment. With chronic treatment of Dox, wild type (WT) animals develop cardiomyopathy evidenced by elongated nuclei, mitochondrial swelling, myofilamental disarray, reduced cardiac output, reduced ejection fraction, reduced left ventricular contractility, and elevated expression of ANF gene. In contrast, p21 knockout (p21KO) mice did not show significantmore » changes in the same parameters in response to Dox treatment. In an effort to understand the mechanism of the resistance against Dox induced cardiomyopathy, we measured levels of antioxidant enzymes and found that p21KO mice did not contain elevated basal or inducible levels of glutathione peroxidase and catalase. Measurements of 6 circulating cytokines indicated elevation of IL-6, IL-12, IFN{gamma} and TNF{alpha} in Dox treated WT mice but not p21KO mice. Dox induced elevation of IL-6 mRNA was detected in the myocardium of WT mice but not p21KO mice. While the mechanism of the resistance against Dox induced cardiomyopathy remains unclear, lack of inflammatory response may contribute to the observed cardiac protection in p21KO mice. -- Highlights: Black-Right-Pointing-Pointer Doxorubicin induces p21 elevation in the myocardium. Black-Right-Pointing-Pointer Doxorubicin causes dilated cardiomyopathy in wild type mice. Black-Right-Pointing-Pointer p21 Knockout mice are resistant against doxorubicin induced cardiomyopathy. Black-Right-Pointing-Pointer Lack of inflammatory response correlates with the resistance in p21 knockout mice.« less

  3. Liver-Specific Deletion of Integrin-Linked Kinase in Mice Attenuates Hepatotoxicity and Improves Liver Regeneration After Acetaminophen Overdose.

    PubMed

    Bhushan, Bharat; Edwards, Genea; Desai, Aishwarya; Michalopoulos, George K; Apte, Udayan

    2016-01-01

    Acetaminophen (APAP) overdose is the major cause of acute liver failure in the US. Prompt liver regeneration is critical for recovery after APAP hepatotoxicity, but mechanisms remain elusive. Extracellular matrix (ECM)-mediated signaling via integrin-linked kinase (ILK) regulates liver regeneration after surgical resection. However, the role of ECM signaling via ILK in APAP toxicity and compensatory regeneration is unknown, which was investigated in this study using liver-specific ILK knockout (KO) mice. ILK KO and wild-type (WT) mice were treated with 300 mg/kg APAP, and injury and regeneration were studied at 6 and 24 h after APAP treatment. ILK KO mice developed lower liver injury after APAP overdose, which was associated with decreased JNK activation (a key mediator of APAP toxicity). Further, higher glutathione levels after APAP treatment and lower APAP protein adducts levels, along with lower levels of CYP2E1, suggest decreased metabolic activation of APAP in ILK KO mice. Interestingly, despite lower injury, ILK KO mice had rapid and higher liver regeneration after APAP overdose accompanied with increased β-catenin signaling. In conclusion, liver-specific deletion of ILK improved regeneration, attenuated toxicity after APAP overdose, and decreased metabolic activation of APAP. Our study also indicates that ILK-mediated ECM signaling plays a role in the regulation of CYP2E1 and may affect toxicity of several centrilobular hepatotoxicants including APAP.

  4. Behavioural and neurobiological consequences of macrophage migration inhibitory factor gene deletion in mice.

    PubMed

    Bay-Richter, Cecilie; Janelidze, Shorena; Sauro, Analise; Bucala, Richard; Lipton, Jack; Deierborg, Tomas; Brundin, Lena

    2015-09-04

    Evidence from clinical studies and animal models show that inflammation can lead to the development of depression. Macrophage migration inhibitory factor (MIF) is an important multifunctional cytokine that is synthesized by several cell types in the brain. MIF can increase production of other cytokines, activates cyclooxygenase (COX)-2 and can counter-regulate anti-inflammatory effects of glucocorticoids. Increased plasma levels of MIF are associated with hypothalamic-pituitary-adrenal (HPA) axis dysregulation and depressive symptoms in patients. In contrast, MIF knockout (KO) mice have been found to exhibit increased depressive-like behaviour. The exact role for MIF in depression is therefore still controversial. To further understand the role of MIF in depression, we studied depressive-like behaviour in congenic male and female MIF KO mice and wild-type (WT) littermates and the associated neurobiological mechanisms underlying the behavioural outcome. MIF KO and WT mice were tested for spontaneous locomotor activity in the open-field test, anhedonia-like behaviour in the sucrose preference test (SPT), as well as behavioural despair in the forced swim test (FST) and tail suspension test (TST). Brain and serum levels of cytokines, the enzymes COX-2 and indoleamine-2,3-dioxygenase (IDO) and the glucocorticoid hormone corticosterone were measured by RT-qPCR and/or high-sensitivity electrochemiluminescence-based multiplex immunoassays. Monoamines and metabolites were examined using HPLC. We found that MIF KO mice of both sexes displayed decreased depressive-like behaviour as measured in the FST. In the TST, a similar, but non-significant, trend was also found. IFN-γ levels were decreased, and dopamine metabolism increased in MIF KO mice. Decreased brain IFN-γ levels predicted higher striatal dopamine levels, and high dopamine levels in turn were associated with reduced depressive-like behaviour. In the SPT, there was a sex-specific discrepancy, where male MIF KO mice

  5. Genetic Restoration of Plasma ApoE Improves Cognition and Partially Restores Synaptic Defects in ApoE-Deficient Mice.

    PubMed

    Lane-Donovan, Courtney; Wong, Wen Mai; Durakoglugil, Murat S; Wasser, Catherine R; Jiang, Shan; Xian, Xunde; Herz, Joachim

    2016-09-28

    Alzheimer's disease (AD) is the most common form of dementia in individuals over the age of 65 years. The most prevalent genetic risk factor for AD is the ε4 allele of apolipoprotein E (ApoE4), and novel AD treatments that target ApoE are being considered. One unresolved question in ApoE biology is whether ApoE is necessary for healthy brain function. ApoE knock-out (KO) mice have synaptic loss and cognitive dysfunction; however, these findings are complicated by the fact that ApoE knock-out mice have highly elevated plasma lipid levels, which may independently affect brain function. To bypass the effect of ApoE loss on plasma lipids, we generated a novel mouse model that expresses ApoE normally in peripheral tissues, but has severely reduced ApoE in the brain, allowing us to study brain ApoE loss in the context of a normal plasma lipid profile. We found that these brain ApoE knock-out (bEKO) mice had synaptic loss and dysfunction similar to that of ApoE KO mice; however, the bEKO mice did not have the learning and memory impairment observed in ApoE KO mice. Moreover, we found that the memory deficit in the ApoE KO mice was specific to female mice and was fully rescued in female bEKO mice. Furthermore, while the AMPA/NMDA ratio was reduced in ApoE KO mice, it was unchanged in bEKO mice compared with controls. These findings suggest that plasma lipid levels can influence cognition and synaptic function independent of ApoE expression in the brain. One proposed treatment strategy for Alzheimer's disease (AD) is the reduction of ApoE, whose ε4 isoform is the most common genetic risk factor for the disease. A major concern of this strategy is that an animal model of ApoE deficiency, the ApoE knock-out (KO) mouse, has reduced synapses and cognitive impairment; however, these mice also develop dyslipidemia and severe atherosclerosis. Here, we have shown that genetic restoration of plasma ApoE to wild-type levels normalizes plasma lipids in ApoE KO mice. While this does

  6. Sterol O-acyltransferase 1 deficiency improves defective insulin signaling in the brains of mice fed a high-fat diet.

    PubMed

    Xu, Ning; Meng, Hao; Liu, Tian-Yi; Feng, Ying-Li; Qi, Yuan; Zhang, Dong-Huan; Wang, Hong-Lei

    2018-05-05

    Insulin resistance induced by a high-fat diet (HFD) is related to metabolic diseases, and sterol O-acyltransferase 1 (SOAT1) is a key enzyme for the biosynthesis of cholesteryl ester. In the present study, wild-type (WT) mice and SOAT1-knockout (KO) mice with a C57BL6 background fed a HFD were used to explore the role of SOAT1 in the hypothalamus. The results show that the WT mice exhibited a significant increase in body weight as well as hepatic histologic changes; they also had a lower glucose and insulin tolerance than the WT mice fed a normal diet. However, the metabolic syndrome was attenuated in the SOAT1-KO HFD-fed mice. With regard to brain function, the SOAT1-KO HFD-fed mice showed improved cognitive function; they also manifested reduced levels of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6, which would otherwise be raised by a HFD. In addition, the HFD led to the overexpression of GFAP and phosphorylated NF-κB in the hypothalamus, changes that were reversed in the SOAT1-KO HFD-fed mice. Moreover, SOAT1-KO mice improved HFD-caused defective hypothalamic insulin resistance, as evidenced by the upregulation of p-insulin receptor (INSR), p-AKT and p-glycogen synthase kinase (GSK)-3β, while the downregulation of p-AMP-activated protein kinase (AMPK)-α and p-acetyl-CoA carboxylase (ACC)-α. In addition, similar results were observed in high fructose (HFR)-stimulated astrocytes (ASTs) isolated from WT or KO mice. These results suggest that SOAT1 plays an important role in hypothalamic insulin sensitivity, linked to cognitive impairment, in HFD-fed mice. Copyright © 2018. Published by Elsevier Inc.

  7. Sco2 deficient mice develop increased adiposity and insulin resistance.

    PubMed

    Hill, Shauna; Deepa, Sathyaseelan S; Sataranatarajan, Kavithalakshmi; Premkumar, Pavithra; Pulliam, Daniel; Liu, Yuhong; Soto, Vanessa Y; Fischer, Kathleen E; Van Remmen, Holly

    2017-11-05

    Cytochrome c oxidase (COX) is an essential transmembrane protein complex (Complex IV) in the mitochondrial respiratory electron chain. Mutations in genes responsible for the assembly of COX are associated with Leigh syndrome, cardiomyopathy, spinal muscular atrophy and other fatal metabolic disorders in humans. Previous studies have shown that mice lacking the COX assembly protein Surf1 (Surf1 -/- mice) paradoxically show a number of beneficial metabolic phenotypes including increased insulin sensitivity, upregulation of mitochondrial biogenesis, induction of stress response pathways and increased lifespan. To determine whether these effects are specific to the Surf1 mutation or a more general effect of reduced COX activity, we asked whether a different mutation causing reduced COX activity would have similar molecular and physiologic changes. Sco2 knock-in/knock-out (KI/KO) mice in which one allele of the Sco2 gene that encodes a copper chaperone required for COX activity is deleted and the second allele is mutated, have previously been shown to be viable despite a 30-60% reduction in COX activity. In contrast to the Surf1 -/- mice, we show that Sco2 KI/KO mice have increased fat mass, associated with reduced β-oxidation and increased adipogenesis markers, reduced insulin receptor beta (IR-β levels in adipose tissue, reduced muscle glucose transporter 4 (Glut4) levels and a impaired response to the insulin tolerance test consistent with insulin resistance. COX activity and protein are reduced approximately 50% in adipose tissue from the Sco2 KI/KO mice. Consistent with the increase in adipose tissue mass, the Sco2 KI/KO mice also show increased hepatosteatosis, elevated serum and liver triglyceride and increased serum cholesterol levels compared to wild-type controls. In contrast to the Surf1 -/- mice, which show increased mitochondrial number, upregulation of the mitochondrial unfolded protein response (UPR MT ) pathway and no significant change in

  8. T1R2 and T1R3 subunits are individually unnecessary for normal affective licking responses to Polycose: implications for saccharide taste receptors in mice.

    PubMed

    Treesukosol, Yada; Blonde, Ginger D; Spector, Alan C

    2009-04-01

    The T1R2 and T1R3 proteins are expressed in taste receptor cells and form a heterodimer binding with compounds described as sweet by humans. We examined whether Polycose taste might be mediated through this heterodimer by testing T1R2 knockout (KO) and T1R3 KO mice and their wild-type (WT) littermate controls in a series of brief-access taste tests (25-min sessions with 5-s trials). Sucrose, Na-saccharin, and Polycose were each tested for three consecutive sessions with order of presentation varied among subgroups in a Latin-Square manner. Both KO groups displayed blunted licking responses and initiated significantly fewer trials of sucrose and Na-saccharin across a range of concentrations. KO mice tested after Polycose exposure demonstrated some degree of concentration-dependent licking of sucrose, likely attributable to learning related to prior postingestive experience. These results are consistent with prior findings in the literature, implicating the T1R2+3 heterodimer as the principal taste receptor for sweet-tasting ligands, and also provide support for the potential of postingestive experience to influence responding in the KO mice. In contrast, T1R2 KO and T1R3 KO mice displayed concentration-dependent licking responses to Polycose that tracked those of their WT controls and in some cases licked midrange concentrations more; the number of Polycose trials initiated overall did not differ between KO and WT mice. Thus, the T1R2 and T1R3 proteins are individually unnecessary for normal concentration-dependent licking of Polycose to be expressed in a brief-access test. Whether at least one of these T1R protein subunits is necessary for normal Polycose responsiveness remains untested. Alternatively, there may be a novel taste receptor(s) that mediates polysaccharide taste.

  9. Prohormone convertase 2 activity is increased in the hippocampus of Wfs1 knockout mice.

    PubMed

    Tein, Karin; Kasvandik, Sergo; Kõks, Sulev; Vasar, Eero; Terasmaa, Anton

    2015-01-01

    Mutations in WFS1 gene cause Wolfram syndrome, which is a rare autosomal recessive disorder, characterized by diabetes insipidus, diabetes mellitus, optic nerve atrophy, and deafness. The WFS1 gene product wolframin is located in the endoplasmic reticulum. Mice lacking this gene exhibit disturbances in the processing and secretion of peptides, such as vasopressin and insulin. In the brain, high levels of the wolframin protein have been observed in the hippocampus, amygdala, and limbic structures. The aim of this study was to investigate the effect of Wfs1 knockout (KO) on peptide processing in mouse hippocampus. A peptidomic approach was used to characterize individual peptides in the hippocampus of wild-type and Wfs1 KO mice. We identified 126 peptides in hippocampal extracts and the levels of 10 peptides differed between Wfs1 KO and wild-type mice at P < 0.05. The peptide with the largest alteration was little-LEN, which level was 25 times higher in the hippocampus of Wfs1 KO mice compared to wild-type mice. Processing (cleavage) of little-LEN from the Pcsk1n gene product proSAAS involves prohormone convertase 2 (PC2). Thus, PC2 activity was measured in extracts prepared from the hippocampus of Wfs1 KO mice. The activity of PC2 in Wfs1 mutant mice was significantly higher (149.9 ± 2.3%, p < 0.0001, n = 8) than in wild-type mice (100.0 ± 7.0%, n = 8). However, Western blot analysis showed that protein levels of 7B2, proPC2 and PC2 were same in both groups, and so were gene expression levels. Processing of proSAAS is altered in the hippocampus of Wfs1-KO mice, which is caused by increased activity of PC2. Increased activity of PC2 in Wfs1 KO mice is not caused by alteration in the levels of PC2 protein. Our results suggest a functional link between Wfs1 and PC2. Thus, the detailed molecular mechanism of the role of Wfs1 in the regulation of PC2 activity needs further investigation.

  10. Prohormone convertase 2 activity is increased in the hippocampus of Wfs1 knockout mice

    PubMed Central

    Tein, Karin; Kasvandik, Sergo; Kõks, Sulev; Vasar, Eero; Terasmaa, Anton

    2015-01-01

    Background: Mutations in WFS1 gene cause Wolfram syndrome, which is a rare autosomal recessive disorder, characterized by diabetes insipidus, diabetes mellitus, optic nerve atrophy, and deafness. The WFS1 gene product wolframin is located in the endoplasmic reticulum. Mice lacking this gene exhibit disturbances in the processing and secretion of peptides, such as vasopressin and insulin. In the brain, high levels of the wolframin protein have been observed in the hippocampus, amygdala, and limbic structures. The aim of this study was to investigate the effect of Wfs1 knockout (KO) on peptide processing in mouse hippocampus. A peptidomic approach was used to characterize individual peptides in the hippocampus of wild-type and Wfs1 KO mice. Results: We identified 126 peptides in hippocampal extracts and the levels of 10 peptides differed between Wfs1 KO and wild-type mice at P < 0.05. The peptide with the largest alteration was little-LEN, which level was 25 times higher in the hippocampus of Wfs1 KO mice compared to wild-type mice. Processing (cleavage) of little-LEN from the Pcsk1n gene product proSAAS involves prohormone convertase 2 (PC2). Thus, PC2 activity was measured in extracts prepared from the hippocampus of Wfs1 KO mice. The activity of PC2 in Wfs1 mutant mice was significantly higher (149.9 ± 2.3%, p < 0.0001, n = 8) than in wild-type mice (100.0 ± 7.0%, n = 8). However, Western blot analysis showed that protein levels of 7B2, proPC2 and PC2 were same in both groups, and so were gene expression levels. Conclusion: Processing of proSAAS is altered in the hippocampus of Wfs1-KO mice, which is caused by increased activity of PC2. Increased activity of PC2 in Wfs1 KO mice is not caused by alteration in the levels of PC2 protein. Our results suggest a functional link between Wfs1 and PC2. Thus, the detailed molecular mechanism of the role of Wfs1 in the regulation of PC2 activity needs further investigation. PMID:26379490

  11. Flavor preference conditioning by different sugars in sweet ageusic Trpm5 knockout mice

    PubMed Central

    Sclafani, Anthony; Ackroff, Karen

    2015-01-01

    Knockout (KO) mice missing the taste signaling protein Trpm5 have greatly attenuated sweetener preferences but develop strong preferences for glucose in 24-h tests, which is attributed to post-oral sugar conditioning. Trpm5 KO mice express mild preferences for galactose but no preferences for fructose in 24-h tests, which suggests that these sugars differ in their post-oral reinforcing effects. Here we investigated sugar-conditioned flavor preferences in Trpm5 KO and C57BL/6J wildtype (B6) mice. The mice were trained to consume a flavored (CS+, e.g. grape) 8% sugar solution and flavored (CS-, e.g., cherry) water on alternating days followed by two-bottle choice tests with CS+ vs. CS- flavors in water and with unflavored sugar vs. water. The KO mice displayed strong preferences (>80%) for the CS+glucose and CS+galactose but not for the CS+fructose flavor. They also preferred glucose and galactose, but not fructose to water. In contrast, the B6 mice preferred all three CS+ flavors to the CS- flavor, and all three sugars to water. In tests with the non-metabolizable sugar α-methyl-D-glucopyranoside (MDG), the KO and B6 mice preferred 8% MDG to water but did not prefer the CS+8%MDG to CS-. However, they preferred a CS+ flavor mixed with 4% MDG over the CS- flavor. Trpm5 KO mice also preferred galactose and MDG to fructose in direct choice tests. The Trpm5 KO data indicate that glucose and, to a lesser extent, galactose and MDG have post-oral reinforcing actions that stimulate intake and preference while fructose has a much weaker effect. The CS+ flavor and sugar preferences of B6 mice may be mediated by the sweet taste and/or post-oral actions of the various sugars. Glucose, galactose, and MDG, but not fructose are ligands for the sodium-glucose transporter 1 (SGLT1) which is implicated in post-oral sugar conditioning in B6 mice. PMID:25497884

  12. Mice lacking the transcriptional regulator Bhlhe40 have enhanced neuronal excitability and impaired synaptic plasticity in the hippocampus.

    PubMed

    Hamilton, Kelly A; Wang, Yue; Raefsky, Sophia M; Berkowitz, Sean; Spangler, Ryan; Suire, Caitlin N; Camandola, Simonetta; Lipsky, Robert H; Mattson, Mark P

    2018-01-01

    Bhlhe40 is a transcription factor that is highly expressed in the hippocampus; however, its role in neuronal function is not well understood. Here, we used Bhlhe40 null mice on a congenic C57Bl6/J background (Bhlhe40 KO) to investigate the impact of Bhlhe40 on neuronal excitability and synaptic plasticity in the hippocampus. Bhlhe40 KO CA1 neurons had increased miniature excitatory post-synaptic current amplitude and decreased inhibitory post-synaptic current amplitude, indicating CA1 neuronal hyperexcitability. Increased CA1 neuronal excitability was not associated with increased seizure severity as Bhlhe40 KO relative to +/+ (WT) control mice injected with the convulsant kainic acid. However, significant reductions in long term potentiation and long term depression at CA1 synapses were observed in Bhlhe40 KO mice, indicating impaired hippocampal synaptic plasticity. Behavioral testing for spatial learning and memory on the Morris Water Maze (MWM) revealed that while Bhlhe40 KO mice performed similarly to WT controls initially, when the hidden platform was moved to the opposite quadrant Bhlhe40 KO mice showed impairments in relearning, consistent with decreased hippocampal synaptic plasticity. To investigate possible mechanisms for increased neuronal excitability and decreased synaptic plasticity, a whole genome mRNA expression profile of Bhlhe40 KO hippocampus was performed followed by a chromatin immunoprecipitation sequencing (ChIP-Seq) screen of the validated candidate genes for Bhlhe40 protein-DNA interactions consistent with transcriptional regulation. Of the validated genes identified from mRNA expression analysis, insulin degrading enzyme (Ide) had the most significantly altered expression in hippocampus and was significantly downregulated on the RNA and protein levels; although Bhlhe40 did not occupy the Ide gene by ChIP-Seq. Together, these findings support a role for Bhlhe40 in regulating neuronal excitability and synaptic plasticity in the hippocampus

  13. Conditional Mutagenesis of Gata6 in SF1-Positive Cells Causes Gonadal-Like Differentiation in the Adrenal Cortex of Mice

    PubMed Central

    Pihlajoki, Marjut; Gretzinger, Elisabeth; Cochran, Rebecca; Kyrönlahti, Antti; Schrade, Anja; Hiller, Theresa; Sullivan, Laura; Shoykhet, Michael; Schoeller, Erica L.; Brooks, Michael D.; Heikinheimo, Markku

    2013-01-01

    Transcription factor GATA6 is expressed in the fetal and adult adrenal cortex and has been implicated in steroidogenesis. To characterize the role of transcription factor GATA6 in adrenocortical development and function, we generated mice in which Gata6 was conditionally deleted using Cre-LoxP recombination with Sf1-cre. The adrenal glands of adult Gata6 conditional knockout (cKO) mice were small and had a thin cortex. Cytomegalic changes were evident in fetal and adult cKO adrenal glands, and chromaffin cells were ectopically located at the periphery of the glands. Corticosterone secretion in response to exogenous ACTH was blunted in cKO mice. Spindle-shaped cells expressing Gata4, a marker of gonadal stroma, accumulated in the adrenal subcapsule of Gata6 cKO mice. RNA analysis demonstrated the concomitant upregulation of other gonadal-like markers, including Amhr2, in the cKO adrenal glands, suggesting that GATA6 inhibits the spontaneous differentiation of adrenocortical stem/progenitor cells into gonadal-like cells. Lhcgr and Cyp17 were overexpressed in the adrenal glands of gonadectomized cKO vs control mice, implying that GATA6 also limits sex steroidogenic cell differentiation in response to the hormonal changes that accompany gonadectomy. Nulliparous female and orchiectomized male Gata6 cKO mice lacked an adrenal X-zone. Microarray hybridization identified Pik3c2g as a novel X-zone marker that is downregulated in the adrenal glands of these mice. Our findings offer genetic proof that GATA6 regulates the differentiation of steroidogenic progenitors into adrenocortical cells. PMID:23471215

  14. The Idea of an Innovated Concept of the Košice Geothermal Project

    NASA Astrophysics Data System (ADS)

    Bujanská, Alena; Böszörményi, László

    2015-11-01

    Slovakia has very limited amounts of fossil resources. However, it has a relatively high potential of geothermal energy which use is far below its possibilities. The most abundant geothermal resource, not only in Slovakia but throughout the central Europe, is Košice basin. Since the publication of the first ideas about the ambitious goal to exploit the geothermal potential of this site, 20 years has passed and three geothermal wells has been made but without any progress. In the article the authors present the idea of a fundamental change in the approach to improve the energy and economic efficiency of the project.

  15. Cntnap2 Knockout Rats and Mice Exhibit Epileptiform Activity and Abnormal Sleep-Wake Physiology.

    PubMed

    Thomas, Alexia M; Schwartz, Michael D; Saxe, Michael D; Kilduff, Thomas S

    2017-01-01

    Although recent innovations have enabled modification of the rat genome, it is unclear whether enhanced utility of rodents as human disease models will result. We compared electroencephalogram (EEG) and behavioral phenotypes of rats and mice with homozygous deletion of Cntnap2, a gene associated with cortical dysplasia-focal epilepsy (CDFE) and autism spectrum disorders (ASD). Male contactin-associated protein-like 2 (Cntnap2) knockout (KO) and wild-type (WT) rats and male Cntnap2 KO and WT mice were implanted with telemeters to record EEG, electromyogram, body temperature, and locomotor activity. Animals were subjected to a test battery for ASD-related behaviors, followed by 24-hr EEG recordings that were analyzed for sleep-wake parameters and subjected to spectral analysis. Cntnap2 KO rats exhibited severe motor seizures, hyperactivity, and increased consolidation of wakefulness and REM sleep. By contrast, Cntnap2 KO mice demonstrated absence seizure-like events, hypoactivity, and wake fragmentation. Although seizures observed in Cntnap2 KO rats were more similar to those in CDFE patients than in KO mice, neither model fully recapitulated the full spectrum of disease symptoms. However, KOs in both species had reduced spectral power in the alpha (9-12 Hz) range during wake, suggesting a conserved EEG biomarker. Deletion of Cntnap2 impacts similar behaviors and EEG measures in rats and mice, but with profound differences in nature and phenotypic severity. These observations highlight the importance of cross-species comparisons to understand conserved gene functions and the limitations of single- species models to provide translational insights relevant to human diseases. © Sleep Research Society 2016. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

  16. Impaired Relaxation of Airway Smooth Muscle in Mice Lacking the Actin-Binding Protein Gelsolin.

    PubMed

    Mikami, Maya; Zhang, Yi; Danielsson, Jennifer; Joell, Tiarra; Yong, Hwan Mee; Townsend, Elizabeth; Khurana, Seema; An, Steven S; Emala, Charles W

    2017-05-01

    Diverse classes of ligands have recently been discovered that relax airway smooth muscle (ASM) despite a transient increase in intracellular calcium concentrations ([Ca 2+ ] i ). However, the cellular mechanisms are not well understood. Gelsolin is a calcium-activated actin-severing and -capping protein found in many cell types, including ASM cells. Gelsolin also binds to phosphatidylinositol 4,5-bisphosphate, making this substrate less available for phospholipase Cβ-mediated hydrolysis to inositol triphosphate and diacylglycerol. We hypothesized that gelsolin plays a critical role in ASM relaxation and mechanistically accounts for relaxation by ligands that transiently increase [Ca 2+ ] i . Isolated tracheal rings from gelsolin knockout (KO) mice showed impaired relaxation to both a β-agonist and chloroquine, a bitter taste receptor agonist, which relaxes ASM, despite inducing transiently increased [Ca 2+ ] i . A single inhalation of methacholine increased lung resistance to a similar extent in wild-type and gelsolin KO mice, but the subsequent spontaneous relaxation was less in gelsolin KO mice. In ASM cells derived from gelsolin KO mice, serotonin-induced Gq-coupled activation increased both [Ca 2+ ] i and inositol triphosphate synthesis to a greater extent compared to cells from wild-type mice, possibly due to the absence of gelsolin binding to phosphatidylinositol 4,5-bisphosphate. Single-cell analysis showed higher filamentous:globular actin ratio at baseline and slower cytoskeletal remodeling dynamics in gelsolin KO cells. Gelsolin KO ASM cells also showed an attenuated decrease in cell stiffness to chloroquine and flufenamic acid. These findings suggest that gelsolin plays a critical role in ASM relaxation and that activation of gelsolin may contribute to relaxation induced by ligands that relax ASM despite a transient increase in [Ca 2+ ] i .

  17. Interleukin-1α and Interleukin-1β play a central role in the pathogenesis of fulminant hepatic failure in mice

    PubMed Central

    Masoud, Rula; Pappo, Orit; Harats, Dror; Kamari, Yehuda

    2017-01-01

    Background and aims Fulminant hepatitis failure (FHF) is marked by the sudden loss of hepatic function, with a severe life-threatening course in persons with no prior history of liver disease. Interleukin (IL)-1α and IL-1β are key inflammatory cytokines but little is known about their role in the development of FHF. The aim of this study was to assess the involvement of IL-1α and IL-1β in the progression of LPS/GalN-induced FHF. Methods WT, IL-1α or IL-1β deficient mice were injected with LPS/GalN. Blood and liver tissue were collected at different time points, FHF related pathways were examined. Results After FHF induction the survival of both IL-1α and IL-1β KO mice was longer than that of WT mice. Lower serum liver enzyme levels, demonstrated reduced hepatic injury in the IL-1α and IL-1βKO mice. Histologically detected liver injury and apoptotic hepatocytes were significantly reduced in the IL-1αand IL-1βKO mice compared to WT mice. Reduced hepatic IkB levels and upregulated NFκB activity in WT mice remained inhibited in IL-1α and IL-1β KO mice. Hepatic expression levels of TNFα and IL-6 were significantly increased in WT mice but not in IL-1α and IL-1β KO mice. Conclusions IL-1α and IL-1β play a central role in the pathogenesis of LPS/GalN-induced FHF. These interleukins are associated with the activation of NFκB signaling, upregulation of the pro-inflammatory cytokines and liver damage and apoptosis. Since neither IL-1α nor IL-1β depletions completely rescued the phenotype, we believe that IL-1α and IL-1β have a similar and probably complementary role in FHF progression. PMID:28953903

  18. Interleukin-1α and Interleukin-1β play a central role in the pathogenesis of fulminant hepatic failure in mice.

    PubMed

    Sultan, Maya; Ben-Ari, Ziv; Masoud, Rula; Pappo, Orit; Harats, Dror; Kamari, Yehuda; Safran, Michal

    2017-01-01

    Fulminant hepatitis failure (FHF) is marked by the sudden loss of hepatic function, with a severe life-threatening course in persons with no prior history of liver disease. Interleukin (IL)-1α and IL-1β are key inflammatory cytokines but little is known about their role in the development of FHF. The aim of this study was to assess the involvement of IL-1α and IL-1β in the progression of LPS/GalN-induced FHF. WT, IL-1α or IL-1β deficient mice were injected with LPS/GalN. Blood and liver tissue were collected at different time points, FHF related pathways were examined. After FHF induction the survival of both IL-1α and IL-1β KO mice was longer than that of WT mice. Lower serum liver enzyme levels, demonstrated reduced hepatic injury in the IL-1α and IL-1βKO mice. Histologically detected liver injury and apoptotic hepatocytes were significantly reduced in the IL-1αand IL-1βKO mice compared to WT mice. Reduced hepatic IkB levels and upregulated NFκB activity in WT mice remained inhibited in IL-1α and IL-1β KO mice. Hepatic expression levels of TNFα and IL-6 were significantly increased in WT mice but not in IL-1α and IL-1β KO mice. IL-1α and IL-1β play a central role in the pathogenesis of LPS/GalN-induced FHF. These interleukins are associated with the activation of NFκB signaling, upregulation of the pro-inflammatory cytokines and liver damage and apoptosis. Since neither IL-1α nor IL-1β depletions completely rescued the phenotype, we believe that IL-1α and IL-1β have a similar and probably complementary role in FHF progression.

  19. Toll-like receptor 2 promotes neurogenesis from the dentate gyrus after photothrombotic cerebral ischemia in mice.

    PubMed

    Seong, Kyung-Joo; Kim, Hyeong-Jun; Cai, Bangrong; Kook, Min-Suk; Jung, Ji-Yeon; Kim, Won-Jae

    2018-03-01

    The subgranular zone (SGZ) of hippocampal dentate gyrus (HDG) is a primary site of adult neurogenesis. Toll-like receptors (TLRs), are involved in neural system development of Drosophila and innate immune response of mammals. TLR2 is expressed abundantly in neurogenic niches such as adult mammalian hippocampus. It regulates adult hippocampal neurogenesis. However, the role of TLR2 in adult neurogenesis is not well studied in global or focal cerebral ischemia. Therefore, this study aimed to investigate the role of TLR2 in adult neurogenesis after photochemically induced cerebral ischemia. At 7 days after photothrombotic ischemic injury, the number of bromodeoxyuridine (BrdU)-positive cells was increased in both TLR2 knock-out (KO) mice and wild-type (WT) mice. However, the increment rate of BrdU-positive cells was lower in TLR2 KO mice compared to that in WT mice. The number of doublecortin (DCX) and neuronal nuclei (NeuN)-positive cells in HDG was decreased after photothrombotic ischemia in TLR2 KO mice compared to that in WT mice. The survival rate of cells in HDG was decreased in TLR2 KO mice compared to that in WT mice. In contrast, the number of cleaved-caspase 3 (apoptotic marker) and the number of GFAP (glia marker)/BrdU double-positive cells in TLR2 KO mice were higher than that in WT mice. These results suggest that TLR2 can promote adult neurogenesis from neural stem cell of hippocampal dentate gyrus through increasing proliferation, differentiation, and survival from neural stem cells after ischemic injury of the brain.

  20. Cellular prion protein regulates the motor behaviour performance and anxiety-induced responses in genetically modified mice.

    PubMed

    Lobão-Soares, Bruno; Walz, Roger; Carlotti, Carlos Gilberto; Sakamoto, Américo Ceiki; Calvo, Fabrício; Terzian, Ana Luiza Bernardes; da Silva, Juliana Almeida; Wichert-Ana, Lauro; Coimbra, Norberto Cysne; Bianchin, Marino Muxfeldt

    2007-10-01

    The cellular prion protein (PrP(C)) is a sialoglycoprotein involved in neuroplasticity processes and synaptic transmission. This study investigated behavioural responses (balance in the rota-rod test at 24 rpm, motility in the open-field test, anxiety in the elevated plus-maze test) in Zurich developed wild-type adult mice (WT, controls of normal PrP(C) expression), in knockout (KO) mice (Prnp(0/0), with no PrP(C) expression), and in PrP(C) overexpressing Tg-20 mice. After 8 min in the rota-rod test, Tg-20 animals presented significantly fewer falls (1.08+/-1.56 falls) than both WT (7.27+/-4.36) and KO (7.6+/-6.15) mice (p<0.01). In the open field test, Tg-20 animals showed significantly increased motility [rearing=23.4+/-7.85, crossing=97.30+/-32.11) when compared with KO mice (rearing=5.45+/-3.69 and crossing=59.73+/-15.43) or WT mice (rearing=6.5+/-20.23 and crossing=45.18+/-20.33) (p<0.01). In the elevated plus-maze test, Tg-20 mice showed less anxiety (head projections=7.3+/-1.62) when compared with WT animals (3.38+/-0.67) (p<0.05). Moreover, KO mice spent more time in the centre of the plus maze (37.80+/-5.57 s) than did WT mice (22.57+/-3.82) (p<0.05). PrP(C) overexpressing mice evoked increased motility, less anxiety, and increased equilibrium when compared with WT control animals in the behavioural protocols used. KO animals also tended to evoke fewer anxiety-related responses in the elevated plus-maze test. These findings indicate that the levels of PrP(C) in adult life are associated with possible changes in motility, anxiety, and equilibrium.

  1. Diet-induced adipose tissue expansion is mitigated in mice with a targeted inactivation of mesoderm specific transcript (Mest).

    PubMed

    Anunciado-Koza, Rea P; Manuel, Justin; Mynatt, Randall L; Zhang, Jingying; Kozak, Leslie P; Koza, Robert A

    2017-01-01

    Interindividual variation of white adipose tissue (WAT) expression of mesoderm specific transcript (Mest), a paternally-expressed imprinted gene belonging to the α/β-hydrolase fold protein family, becomes apparent among genetically inbred mice fed high fat diet (HFD) and is positively associated with adipose tissue expansion (ATE). To elucidate a role for MEST in ATE, mice were developed with global and adipose tissue inactivation of Mest. Mice with homozygous (MestgKO) and paternal allelic (MestpKO) inactivation of Mest were born at expected Mendelian frequencies, showed no behavioral or physical abnormalities, and did not perturb expression of the Mest locus-derived microRNA miR-335. MestpKO mice fed HFD showed reduced ATE and adipocyte hypertrophy, improved glucose tolerance, and reduced WAT expression of genes associated with hypoxia and inflammation compared to littermate controls. Remarkably, caloric intake and energy expenditure were unchanged between genotypes. Mice with adipose tissue inactivation of Mest were phenotypically similar to MestpKO, supporting a role for WAT MEST in ATE. Global profiling of WAT gene expression of HFD-fed control and MestpKO mice detected few differences between genotypes; nevertheless, genes with reduced expression in MestpKO mice were associated with immune processes and consistent with improved glucose homeostasis. Ear-derived mesenchymal stem cells (EMSC) from MestgKO mice showed no differences in adipogenic differentiation compared to control cells unless challenged by shRNA knockdown of Gpat4, an enzyme that mediates lipid accumulation in adipocytes. Reduced adipogenic capacity of EMSC from MestgKO after Gpat4 knockdown suggests that MEST facilitates lipid accumulation in adipocytes. Our data suggests that reduced diet-induced ATE in MEST-deficient mice diminishes hypoxia and inflammation in WAT leading to improved glucose tolerance and insulin sensitivity. Since inactivation of Mest in mice has minimal additional

  2. Multi-Copper Ferroxidase-Deficient Mice Have Increased Brain Iron Concentrations and Learning and Memory Deficits.

    PubMed

    Zheng, Jiashuo; Jiang, Ruiwei; Chen, Min; Maimaitiming, Zaitunamu; Wang, Junzhuo; Anderson, Gregory J; Vulpe, Chris D; Dunaief, Joshua L; Chen, Huijun

    2018-04-01

    The accumulation of iron occurs in the central nervous system (CNS) in several neurodegenerative diseases. Although multi-copper ferroxidases (MCFs) play an important role in cellular iron metabolism and homeostasis, the mechanism of MCFs in the CNS remains unclear. The aim was to study the role of MCFs in CNS iron metabolism and homeostasis by using hephaestin/ceruloplasmin (Heph/Cp) double knockout (KO) mice. Heph/Cp double KO male mice were generated by crossing both single KO mice. In Heph/Cp KO and wild-type (WT) control mice at 4 wk and 6 mo of age, iron concentrations of selected brain regions were measured by atomic absorption spectrophotometry, and gene expressions of Heph, Cp, ferroportin 1 (Fpn1) [+ iron responsive element (IRE)], L-ferritin, H-ferritin, transferrin receptor 1 (Tfrc), and divalent metal transporter 1 (Dmt1) (+IRE) were quantitated by quantitative reverse transcriptase-polymerase chain reaction. Brain region L-ferritin protein concentration, superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities and malondialdehyde (MDA) concentration were also determined. Learning and memory abilities in Heph/Cp KO and WT control mice at 6 mo of age were tested by the IntelliCage system (New Behavior). Iron concentration was significantly higher in Heph/Cp KO mice than in WT control mice at 4 wk of age in the cortex (50%), hippocampus (120%), brainstem (35%), and cerebellum (220%) and at 6 mo of age in the cortex (140%), hippocampus (420%), brainstem (560%), and cerebellum (340%). L-Ferritin and MDA concentrations were significantly higher and SOD and GPx activities were significantly lower in the cortex, hippocampus, brainstem, and cerebellum of KO mice than in those of WT controls at both 4 wk and 6 mo of age. Iron-related gene expressions also differed significantly between groups. Learning and memory deficits occurred in Heph/Cp KO mice at 6 mo of age. Mutation of both MCFs in mice induces iron accumulation in brain regions

  3. Differential Pharmacological Regulation of Sensorimotor Gating Deficit in CB1 Knockout Mice and Associated Neurochemical and Histological Alterations

    PubMed Central

    Ortega-Álvaro, Antonio; Navarrete, Francisco; Aracil-Fernández, Auxiliadora; Navarro, Daniela; Berbel, Pere; Manzanares, Jorge

    2015-01-01

    The endocannabinoid system has been widely involved in the pathophysiology of sensorimotor gating deficits. This study aimed to evaluate the pharmacological modulation of the sensorimotor gating impairment induced by cannabinoid CB1 receptor (CB1r) deletion. For this purpose, the prepulse inhibition (PPI) paradigm was used to evaluate the effect of two antipsychotics drugs (risperidone and haloperidol) and a psychostimulant (methylphenidate) on the preattentional deficit presented by CB1KO mice. Furthermore, the effects of the CB1r antagonist AM251 on PPI were evaluated in WT mice. Real-time PCR and immunohistochemical studies were carried out to analyze dopamine transporter (DAT) and α-2C adrenergic receptor (ADRA2C) gene expressions and the distribution of parvalbumin (PV) and cholecystokinin-8 (CCK) immunoreactive (ir) cortical neurons, respectively. Neither risperidone nor haloperidol significantly modified the PPI of WT and CB1KO mice, whereas methylphenidate improved the preattentional deficit of CB1KO mice. In addition, treatment with AM251 (3 mg/kg; i.p.) significantly decreased the PPI of WT animals. The administration of methylphenidate increased DAT and ADRA2C gene expressions in CB1KO mice without producing any effect in WT animals. Immunohistochemical studies revealed that there were no significant changes in CCK immunolabeling between WT and CB1KO mice, whereas the radial distribution of PV-ir neurons was abnormal in CB1KO mice. These data further support the important role of CB1r in sensorimotor gating regulation and the therapeutic usefulness of methylphenidate for the treatment of psychiatric disorders with associated preattentional deficits. PMID:25895455

  4. Mammalian target of rapamycin is essential for cardiomyocyte survival and heart development in mice

    SciTech Connect

    Zhang, Pengpeng; Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070; Department of Animal Sciences, Purdue University, West Lafayette, IN 47907

    2014-09-12

    Highlights: • mTOR is a critical regulator of many biological processes yet its function in heart is not well understood. • MCK-Cre/Mtor{sup flox/flox} mice were established to delete Mtor in cardiomyocytes. • The mTOR-mKO mice developed normally but die prematurely within 5 weeks after birth due to heart disease. • The mTOR-mKO mice had dilated myocardium and increased cell death. • mTOR-mKO hearts had reduced expression of metabolic genes and activation of mTOR target proteins. - Abstract: Mammalian target of rapamycin (mTOR) is a critical regulator of protein synthesis, cell proliferation and energy metabolism. As constitutive knockout of Mtor leadsmore » to embryonic lethality, the in vivo function of mTOR in perinatal development and postnatal growth of heart is not well defined. In this study, we established a muscle-specific mTOR conditional knockout mouse model (mTOR-mKO) by crossing MCK-Cre and Mtor{sup flox/flox} mice. Although the mTOR-mKO mice survived embryonic and perinatal development, they exhibited severe postnatal growth retardation, cardiac muscle pathology and premature death. At the cellular level, the cardiac muscle of mTOR-mKO mice had fewer cardiomyocytes due to apoptosis and necrosis, leading to dilated cardiomyopathy. At the molecular level, the cardiac muscle of mTOR-mKO mice expressed lower levels of fatty acid oxidation and glycolysis related genes compared to the WT littermates. In addition, the mTOR-mKO cardiac muscle had reduced Myh6 but elevated Myh7 expression, indicating cardiac muscle degeneration. Furthermore, deletion of Mtor dramatically decreased the phosphorylation of S6 and AKT, two key targets downstream of mTORC1 and mTORC2 mediating the normal function of mTOR. These results demonstrate that mTOR is essential for cardiomyocyte survival and cardiac muscle function.« less

  5. Role of Keap1-Nrf2 signaling in depression and dietary intake of glucoraphanin confers stress resilience in mice.

    PubMed

    Yao, Wei; Zhang, Ji-Chun; Ishima, Tamaki; Dong, Chao; Yang, Chun; Ren, Qian; Ma, Min; Han, Mei; Wu, Jin; Suganuma, Hiroyuki; Ushida, Yusuke; Yamamoto, Masayuki; Hashimoto, Kenji

    2016-07-29

    The transcription factor Keap1-Nrf2 system plays a key role in inflammation which is involved in depression. We found lower expression of Keap1 and Nrf2 proteins in the prefrontal cortex (PFC), CA3 and dentate gyrus (DG) of hippocampus in mice with depression-like phenotype compared to control mice. Serum levels of pro-inflammatory cytokines in Nrf2 knock-out (KO) mice were higher than those of wild-type mice, suggestive of enhanced inflammation in KO mice. Decreased brain-derived neurotrophic factor (BDNF) and its receptor tropomyosin-receptor-kinase B (TrkB) signaling in the PFC, CA3 and DG plays a role in the depression-like phenotype of Nrf2 KO mice. TrkB agonist 7,8-dihydroxyflavone, but not antagonist ANA-12, produced antidepressant effects in Nrf2 KO mice, by stimulating TrkB in the PFC, CA3 and DG. Pretreatment with Nrf2 activator sulforaphane (SFN) prevented the depression-like phenotype induced after repeated social defeat stress. Interestingly, dietary intake of 0.1% glucoraphanin (a precursor of SFN) containing food during juvenile and adolescent stages also prevented the depression-like phenotype evoked in adulthood, after repeated social defeat stress. These findings suggest that Keap1-Nrf2 system plays a key role in depression and that dietary intake of SFN-rich food during juvenile stages and adolescence can confer stress resilience in adulthood.

  6. Impaired Processing of Prohormones in Secretogranin III-Null Mice Causes Maladaptation to an Inadequate Diet and Stress.

    PubMed

    Maeda, Yoshinori; Kudo, Saki; Tsushima, Ken; Sato, Eri; Kubota, Chisato; Kayamori, Aika; Bochimoto, Hiroki; Koga, Daisuke; Torii, Seiji; Gomi, Hiroshi; Watanabe, Tsuyoshi; Hosaka, Masahiro

    2018-02-01

    Secretogranin III (SgIII), a member of the granin family, binds both to another granin, chromogranin A (CgA), and to a cholesterol-rich membrane that is destined for secretory granules (SGs). The knockdown of SgIII in adrenocorticotropic hormone (ACTH)-producing AtT-20 cells largely impairs the regulated secretion of CgA and ACTH. To clarify the physiological roles of SgIII in vivo, we analyzed hormone secretion and SG biogenesis in newly established SgIII-knockout (KO) mice. Although the SgIII-KO mice were viable and fertile and exhibited no overt abnormalities under ordinary rearing conditions, a high-fat/high-sucrose diet caused pronounced obesity in the mice. Furthermore, in the SgIII-KO mice compared with wild-type (WT) mice, the stimulated secretion of active insulin decreased substantially, whereas the storage of proinsulin increased in the islets. The plasma ACTH was also less elevated in the SgIII-KO mice than in the WT mice after chronic restraint stress, whereas the storage level of the precursor proopiomelanocortin in the pituitary gland was somewhat increased. These findings suggest that the lack of SgIII causes maladaptation of endocrine cells to an inadequate diet and stress by impairing the proteolytic conversion of prohormones in SGs, whereas SG biogenesis and the basal secretion of peptide hormones under ordinary conditions are ensured by the compensatory upregulation of other residual granins or factors. Copyright © 2018 Endocrine Society.

  7. Mice deficient in CD38 develop an attenuated form of collagen type II-induced arthritis.

    PubMed

    Postigo, Jorge; Iglesias, Marcos; Cerezo-Wallis, Daniela; Rosal-Vela, Antonio; García-Rodríguez, Sonia; Zubiaur, Mercedes; Sancho, Jaime; Merino, Ramón; Merino, Jesús

    2012-01-01

    CD38, a type II transmembrane glycoprotein expressed in many cells of the immune system, is involved in cell signaling, migration and differentiation. Studies in CD38 deficient mice (CD38 KO mice) indicate that this molecule controls inflammatory immune responses, although its involvement in these responses depends on the disease model analyzed. Here, we explored the role of CD38 in the control of autoimmune responses using chicken collagen type II (col II) immunized C57BL/6-CD38 KO mice as a model of collagen-induced arthritis (CIA). We demonstrate that CD38 KO mice develop an attenuated CIA that is accompanied by a limited joint induction of IL-1β and IL-6 expression, by the lack of induction of IFNγ expression in the joints and by a reduction in the percentages of invariant NKT (iNKT) cells in the spleen. Immunized CD38 KO mice produce high levels of circulating IgG1 and low of IgG2a anti-col II antibodies in association with reduced percentages of Th1 cells in the draining lymph nodes. Altogether, our results show that CD38 participates in the pathogenesis of CIA controlling the number of iNKT cells and promoting Th1 inflammatory responses.

  8. The transcription factor GATA4 promotes myocardial regeneration in neonatal mice.

    PubMed

    Malek Mohammadi, Mona; Kattih, Badder; Grund, Andrea; Froese, Natali; Korf-Klingebiel, Mortimer; Gigina, Anna; Schrameck, Ulrike; Rudat, Carsten; Liang, Qiangrong; Kispert, Andreas; Wollert, Kai C; Bauersachs, Johann; Heineke, Joerg

    2017-02-01

    Heart failure is often the consequence of insufficient cardiac regeneration. Neonatal mice retain a certain capability of myocardial regeneration until postnatal day (P)7, although the underlying transcriptional mechanisms remain largely unknown. We demonstrate here that cardiac abundance of the transcription factor GATA4 was high at P1, but became strongly reduced at P7 in parallel with loss of regenerative capacity. Reconstitution of cardiac GATA4 levels by adenoviral gene transfer markedly improved cardiac regeneration after cryoinjury at P7. In contrast, the myocardial scar was larger in cardiomyocyte-specific Gata4 knockout (CM-G4-KO) mice after cryoinjury at P0, indicative of impaired regeneration, which was accompanied by reduced cardiomyocyte proliferation and reduced myocardial angiogenesis in CM-G4-KO mice. Cardiomyocyte proliferation was also diminished in cardiac explants from CM-G4-KO mice and in isolated cardiomyocytes with reduced GATA4 expression. Mechanistically, decreased GATA4 levels caused the downregulation of several pro-regenerative genes (among them interleukin-13, Il13) in the myocardium. Interestingly, systemic administration of IL-13 rescued defective heart regeneration in CM-G4-KO mice and could be evaluated as therapeutic strategy in the future. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

  9. Deletion of calponin 2 in macrophages attenuates the severity of inflammatory arthritis in mice.

    PubMed

    Huang, Qi-Quan; Hossain, M Moazzem; Sun, Wen; Xing, Lianping; Pope, Richard M; Jin, J-P

    2016-10-01

    Calponin is an actin cytoskeleton-associated protein that regulates motility-based cellular functions. Three isoforms of calponin are present in vertebrates, among which calponin 2 encoded by the Cnn2 gene is expressed in multiple types of cells, including blood cells from the myeloid lineage. Our previous studies demonstrated that macrophages from Cnn2 knockout (KO) mice exhibit increased migration and phagocytosis. Intrigued by an observation that monocytes and macrophages from patients with rheumatoid arthritis had increased calponin 2, we investigated anti-glucose-6-phosphate isomerase serum-induced arthritis in Cnn2-KO mice for the effect of calponin 2 deletion on the pathogenesis and pathology of inflammatory arthritis. The results showed that the development of arthritis was attenuated in systemic Cnn2-KO mice with significantly reduced inflammation and bone erosion than that in age- and stain background-matched C57BL/6 wild-type mice. In vitro differentiation of calponin 2-null mouse bone marrow cells produced fewer osteoclasts with decreased bone resorption. The attenuation of inflammatory arthritis was confirmed in conditional myeloid cell-specific Cnn2-KO mice. The increased phagocytotic activity of calponin 2-null macrophages may facilitate the clearance of autoimmune complexes and the resolution of inflammation, whereas the decreased substrate adhesion may reduce osteoclastogenesis and bone resorption. The data suggest that calponin 2 regulation of cytoskeleton function plays a novel role in the pathogenesis of inflammatory arthritis, implicating a potentially therapeutic target. Copyright © 2016 the American Physiological Society.

  10. Hyperphagia and leptin resistance in tissue inhibitor of metalloproteinase-2 deficient mice.

    PubMed

    Stradecki, H M; Jaworski, D M

    2011-03-01

    Obesity is a complex genetic and behavioural disorder arising from the improper integration of peripheral signals at central autonomic centres. For the hypothalamus to respond to dynamic physiological alterations, it must retain a degree of plasticity throughout life. Evidence is mounting that an intricate balance between matrix metalloproteinase (MMP)-mediated extracellular matrix proteolysis and tissue inhibitor of metalloproteinase (TIMP)-mediated proteolysis inhibition contributes to tissue remodelling. However, few studies have examined the role of MMPs/TIMPs in hypothalamic remodelling and energy homeostasis. To determine the contribution of TIMP-2 to the hypothalamic regulation of feeding, body mass and food consumption were monitored in TIMP-2 knockout (KO) mice fed a standard chow or high-fat diet (HFD). TIMP-2 KO mice of both sexes gained more weight than wild-type (WT) mice, even when fed the chow diet. Before the onset of obesity, TIMP-2 KO mice were hyperphagic, without increased orexigenic or decreased anorexigenic neuropeptide expression, but leptin resistant (i.e. reduced leptin-induced anorexigenic response and signal transducer and activator of transcription 3 activation). HFD exacerbated weight gain and hyperleptinaemia. In addition, proteolysis was increased in the arcuate nucleus of TIMP-2 KO mice. These data suggest a role for TIMP-2 in hypothalamic control of feeding and energy homeostasis. © 2011 The Authors. Journal of Neuroendocrinology © 2011 Blackwell Publishing Ltd.

  11. Paraoxonase 1 deficiency in mice is associated with reduced steroid biosynthesis: effects on HDL binding, cholesteryl ester accumulation and scavenger receptor type BI expression.

    PubMed

    Gamliel-Lazarovich, Aviva; Gantman, Anna; Shiner, Maayan; Coleman, Raymond; Aviram, Michael; Keidar, Shlomo

    2010-07-01

    Selective uptake of high density lipoprotein (HDL) cholesteryl ester (CE) is considered as the major source of cholesterol for production of steroids in the adrenal gland in rodents. As paraoxonase 1 (PON1) is an HDL-associated lipo-lactonase that has been shown to increase binding of HDL to macrophages, we used PON1 knock-out (PON1KO) mice to test the possible role of PON1 in corticosterone (CS) biosynthesis. PON1 deficiency was associated with reduced serum CS concentration. Adrenal glands obtained from PON1KO mice had significantly lower CE content compared to adrenals from C57Bl6 control mice. Binding of HDL obtained from PON1KO mice to human adrenocortical carcinoma cell line was found to be significantly lower than that of control HDL, and was associated with decreased CS biosynthesis. Addition of purified PON1 to HDL from PON1KO mice increased HDL binding and CS synthesis. Furthermore, the expression of the HDL receptor, SR-BI, protein and mRNA, was reduced in adrenals from PON1KO mice compared to control mice. When challenged with low salt diet, PON1KO mice demonstrated an increase in adrenal SR-BI gene expression and in serum corticosterone which reached levels similar to those obtained in control mice. PON1 regulates adrenal CS biosynthesis at two levels: (a) via an accessory role in HDL binding properties, and (b) a supportive role in SR-BI expression and CE supply to the cells. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  12. Difference in Perseverative Errors during a Visual Attention Task with Auditory Distractors in Alpha-9 Nicotinic Receptor Subunit Wild Type and Knock-Out Mice.

    PubMed

    Jorratt, Pascal; Delano, Paul H; Delgado, Carolina; Dagnino-Subiabre, Alexies; Terreros, Gonzalo

    2017-01-01

    The auditory efferent system is a neural network that originates in the auditory cortex and projects to the cochlear receptor through olivocochlear (OC) neurons. Medial OC neurons make cholinergic synapses with outer hair cells (OHCs) through nicotinic receptors constituted by α9 and α10 subunits. One of the physiological functions of the α9 nicotinic receptor subunit (α9-nAChR) is the suppression of auditory distractors during selective attention to visual stimuli. In a recent study we demonstrated that the behavioral performance of alpha-9 nicotinic receptor knock-out (KO) mice is altered during selective attention to visual stimuli with auditory distractors since they made less correct responses and more omissions than wild type (WT) mice. As the inhibition of the behavioral responses to irrelevant stimuli is an important mechanism of the selective attention processes, behavioral errors are relevant measures that can reflect altered inhibitory control. Errors produced during a cued attention task can be classified as premature, target and perseverative errors. Perseverative responses can be considered as an inability to inhibit the repetition of an action already planned, while premature responses can be considered as an index of the ability to wait or retain an action. Here, we studied premature, target and perseverative errors during a visual attention task with auditory distractors in WT and KO mice. We found that α9-KO mice make fewer perseverative errors with longer latencies than WT mice in the presence of auditory distractors. In addition, although we found no significant difference in the number of target error between genotypes, KO mice made more short-latency target errors than WT mice during the presentation of auditory distractors. The fewer perseverative error made by α9-KO mice could be explained by a reduced motivation for reward and an increased impulsivity during decision making with auditory distraction in KO mice.

  13. High Dietary Vitamin D Prevents Hypocalcemia and Osteomalacia in CYP27B1 Knockout Mice12

    PubMed Central

    Rowling, Matthew J.; Gliniak, Christy; Welsh, JoEllen; Fleet, James C.

    2008-01-01

    Mice lacking 25-hydroxycholecalciferol [25(OH)D]-1α-hydroxylase (CYP27B1) are growth retarded, hypocalcemic, and have poor bone mineralization. We tested whether high dietary cholecalciferol (VD3) could exert effects in the absence of CYP27B1 in vivo. Weanling male wild-type (WT) and CYP27B1 knockout (KO) mice were fed either a 2% calcium (Ca), 20% lactose rescue diet or an AIN93G diet (0.5% Ca, 0.4% phosphorus) containing 1000 (1K, the rodent requirement, 25 μg), 10,000 (10K, 250 μg), or 20,000 (20K, 500 μg) IU VD3/kg diet until 12 wk when blood and tissues were taken. Serum 25(OH)D was >90 nmol/L in the 1K diet group and increased >4-fold in mice fed 10K and 20K diets. The 1K diet impaired growth and caused hypocalcemia in KO mice; the 10K and 20K diets were as effective as the high Ca rescue diet in preventing these outcomes. High VD3 restored expression of vitamin D-regulated genes in intestine (calbindin D9K) and kidney (CYP27B1, 24-hydroxylase, calbindin D9K) of KO mice. Micro-computed tomography of femora revealed complete recovery of cortical bone in KO mice fed either the rescue or 10K diets but only partial recovery of trabecular bone measures (e.g. 40% lower bone volume, 20% lower trabecular thickness, and 23% increase in trabecular separation). These data show that very high serum 25(OH)D can influence Ca and bone metabolism independent of its conversion to 1,25 dihydroxycholecalciferol. However, neither high dietary Ca nor high dietary VD3 is sufficient to fully recover the phenotype of CYP27B1 KO mice. PMID:18029472

  14. High-intensity exercise training in mice with cardiomyocyte-specific disruption of Serca2.

    PubMed

    Ericsson, Madelene; Andersson, Kristin B; Amundsen, Brage H; Torp, Sverre H; Sjaastad, Ivar; Christensen, Geir; Sejersted, Ole M; Ellingsen, Øyvind

    2010-05-01

    Several lines of evidence indicate that the sarco(endo)plasmic reticulum ATPase type 2 (SERCA2) is essential for maintaining myocardial calcium handling and cardiac pump function. Hence, a reduction in SERCA2 abundance is expected to reduce work performance and maximal oxygen uptake (VO2max) and to limit the response to exercise training. To test this hypothesis, we compared VO2max and exercise capacity in mice with cardiac disruption of Serca2 (SERCA2 KO) with control mice (SERCA2 FF). We also determined whether the effects on VO2max and exercise capacity could be modified by high-intensity aerobic exercise training. Treadmill running at 85-90% of VO2max started 2 wk after Serca2 gene disruption and continued for 4 wk. VO2max and maximal running speed were measured weekly in a metabolic chamber. Cardiac function was assessed by echocardiography during light anesthesia. In sedentary SERCA2 KO mice, the aerobic capacity was reduced by 50% and running speed by 28%, whereas trained SERCA2 KO mice were able to maintain maximal running speed despite a 36% decrease in VO2max. In SERCA2 FF mice, both VO2max and maximal running speed increased by training, while no changes occurred in the sedentary group. Left ventricle dimensions remained unchanged by training in both genotypes. In contrast, training induced right ventricle hypertrophy in SERCA2 KO mice. In conclusion, the SERCA2 protein is essential for sustaining cardiac pump function and exercise capacity. Nevertheless, SERCA2 KO mice were able to maintain maximal running speed in response to exercise training despite a large decrease in VO2max.

  15. The role of endogenous glucocorticoids in glucose metabolism and immune status of MIF-deficient mice.

    PubMed

    Nikolic, Ivana; Vujicic, Milica; Saksida, Tamara; Berki, Timea; Stosic-Grujicic, Stanislava; Stojanovic, Ivana

    2013-08-15

    Macrophage migration inhibitory factor (MIF)-deficient mice develop glucose intolerance and hyperglycemia, but remain entirely responsive to exogenous insulin in adult age. Furthermore, as a consequence of MIF deficiency, the immune response in these mice is predominantly anti-inflammatory. Since MIF is a natural counter-regulator of glucocorticoid action, and it is known that excessive concentration of glucocorticoids contribute both to beta cell dysfunction and immunosuppression, we hypothesized that MIF absence enables elevation of glucocorticoids which in turn caused the observed condition. Our results confirm that MIF-knockout (MIF-KO) mice possess higher levels of circulating corticosterone, but lower expression of glucocorticoid receptor in pancreatic islets, liver and adipose tissue to the one observed in wild type (WT) mice. A significant up-regulation of glucocorticoid receptor expression was however noticed in MIF-deficient lymph node cells. The inhibition of glucocorticoid receptor by RU486 improved tolerance to glucose in MIF-KO mice and restored euglycemia. Although RU486 treatment did not alter the level of glucose receptor GLUT2, it enhanced insulin secretion and up-regulated insulin-triggered Akt phosphorylation within hepatic tissue. Finally, inhibition of glucocorticoid receptor changed anti-inflammatory phenotype of MIF-KO lymphocytes toward a physiological profile. Our results indicate that deregulated glucocorticoid secretion and glucocorticoid receptor expression in the absence of MIF possibly contributes to the development of glucose intolerance and immunosuppression in MIF-KO mice. However, since MIF-KO mice respond normally to insulin and their beta cell function is within physiological range, additional cause for glucose intolerance could be sought in the possible malfunction of their insulin. © 2013 Elsevier B.V. All rights reserved.

  16. [Exogenous estrogen improved calcium homeostasis and skeletal mineralization in vitamin D receptor gene knockout female mice].

    PubMed

    Li, Bing-Yan; Tong, Jian; Zhang, Zeng-Li

    2006-12-25

    It is well known that estrogen can inhibit bone absorption, decrease bone turnover and preserve bone mass. Some studies indicated that the effect of estrogen on calcium and bone is relative to vitamin D system, while others also reported that this effect of estrogen is independent of vitamin D. The genomic effect of 1alpha, 25(OH)(2)D(3)is mediated by the nuclear vitamin D receptor (VDR) in a ligand-dependent manner. Hypocalcemia, hyperparathyroidism and osteomalacia are developed in VDR gene knockout mice. To determine whether the effect of estrogen on calcium and bone is dependent on VDR, this study examined the effect of exogenous estrogen on calcium and bone homeostasis in VDR gene knockout mice. Male and female wild type (WT) and VDR gene knockout heterozygous mice were mated each other and the genotyping of their offsprings were determined by PCR. At age of 21-day, WT and knockout mice were weaned and treated by one of three different regimens: (1) WT-vehicle group: the WT mice were injected with normal saline; (2) VDR KO-vehicle group: the VDR gene knockout mice were injected with normal saline; (3) VDR KO-E group: the VDR gene knockout mice were subcutaneously injected with estradiol, 0.2 mug per mouse, once daily for 1 month. The bone mineral density (BMD) of mice was measured using dual-energy X-ray absorptiometry. All mice were sacrificed at age of 50-day. Blood was taken by heart puncture under anesthesia and serum calcium was measured by autoanalyser.Tibiae were removed, fixed and embedded with the methylmethacrylate (MMA), and undecalcified sections were cut. These sections were stained for mineral with the von Kossa staining procedure and counterstained with toluidine blue. Static histomorphometric analyses were performed on those stained sections. The results showed that the serum calcium level was (2.10+/-0.37) mmol/L in the VDR KO-vehicle mice and rose to (2.80+/-0.41) mmol/L in the VDR KO-E mice although it was still lower than WT-vehicle mice

  17. Further Development of Ko Displacement Theory for Deformed Shape Predictions of Nonuniform Aerospace Structures

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Fleischer, Van Tran

    2009-01-01

    The Ko displacement theory previously formulated for deformed shape predictions of nonuniform beam structures is further developed mathematically. The further-developed displacement equations are expressed explicitly in terms of geometrical parameters of the beam and bending strains at equally spaced strain-sensing stations along the multiplexed fiber-optic sensor line installed on the bottom surface of the beam. The bending strain data can then be input into the displacement equations for calculations of local slopes, deflections, and cross-sectional twist angles for generating the overall deformed shapes of the nonuniform beam. The further-developed displacement theory can also be applied to the deformed shape predictions of nonuniform two-point supported beams, nonuniform panels, nonuniform aircraft wings and fuselages, and so forth. The high degree of accuracy of the further-developed displacement theory for nonuniform beams is validated by finite-element analysis of various nonuniform beam structures. Such structures include tapered tubular beams, depth-tapered unswept and swept wing boxes, width-tapered wing boxes, and double-tapered wing boxes, all under combined bending and torsional loads. The Ko displacement theory, combined with the fiber-optic strain-sensing system, provide a powerful tool for in-flight deformed shape monitoring of unmanned aerospace vehicles by ground-based pilots to maintain safe flights.

  18. Persistent fibroblast growth factor 23 signalling in the parathyroid glands for secondary hyperparathyroidism in mice with chronic kidney disease

    PubMed Central

    Kawakami, Kazuki; Takeshita, Ai; Furushima, Kenryo; Miyajima, Masayasu; Hatamura, Ikuji; Kuro-o, Makoto; Furuta, Yasuhide; Sakaguchi, Kazushige

    2017-01-01

    Secondary hyperparathyroidism, in which parathyroid hormone (PTH) is excessively secreted in response to factors such as hyperphosphataemia, hypocalcaemia, and low 1,25-dihydroxyvitamin D (1,25(OH)2D) levels, is commonly observed in patients with chronic kidney disease (CKD), and is accompanied by high levels of fibroblast growth factor 23 (FGF23). However, the effect of FGF23 on the parathyroid glands (PG) remains controversial. To bind to FGF receptors, FGF23 requires αKlotho, which is highly expressed in the PG. Here, we examined the effects of Fgfr1–3, αKlotho, or Fgfr1–4 ablation specifically in the PG (conditional knockout, cKO). When mice with early to mid-stage CKD with and without cKO were compared, plasma concentrations of calcium, phosphate, FGF23, and 1,25(OH)2D did not change significantly. In contrast, plasma PTH levels, which were elevated in CKD mice, were significantly decreased in cKO mice. PG from CKD mice showed augmentation of cell proliferation, which was significantly suppressed by cKO. Parathyroid tissue cultured for 4 days showed upregulation of PTH secretion and cell proliferation in response to FGF23. Both these effects were inhibited by cKO. These findings suggest that FGF23 is a long-term inducer of parathyroid cell proliferation and PTH secretion, and is one cause of secondary hyperparathyroidism in CKD. PMID:28094278

  19. Vitamin D receptor signaling enhances locomotive ability in mice.

    PubMed

    Sakai, Sadaoki; Suzuki, Miho; Tashiro, Yoshihito; Tanaka, Keisuke; Takeda, Satoshi; Aizawa, Ken; Hirata, Michinori; Yogo, Kenji; Endo, Koichi

    2015-01-01

    Bone fractures markedly reduce quality of life and life expectancy in elderly people. Although osteoporosis increases bone fragility, fractures frequently occur in patients with normal bone mineral density. Because most fractures occur on falling, preventing falls is another focus for reducing bone fractures. In this study, we investigated the role of vitamin D receptor (VDR) signaling in locomotive ability. In the rotarod test, physical exercise enhanced locomotive ability of wild-type (WT) mice by 1.6-fold, whereas exercise did not enhance locomotive ability of VDR knockout (KO) mice. Compared with WT mice, VDR KO mice had smaller peripheral nerve axonal diameter and disordered AChR morphology on the extensor digitorum longus muscle. Eldecalcitol (ED-71, ELD), an analog of 1,25(OH)2 D3 , administered to rotarod-trained C57BL/6 mice enhanced locomotor performance compared with vehicle-treated nontrained mice. The area of AChR cluster on the extensor digitorum longus was greater in ELD-treated mice than in vehicle-treated mice. ELD and 1,25(OH)2 D3 enhanced expression of IGF-1, myelin basic protein, and VDR in rat primary Schwann cells. VDR signaling regulates neuromuscular maintenance and enhances locomotive ability after physical exercise. Further investigation is required, but Schwann cells and the neuromuscular junction are targets of vitamin D3 signaling in locomotive ability. © 2014 American Society for Bone and Mineral Research.

  20. Maintenance of muscle mass and load-induced growth in Muscle RING Finger 1 null mice with age.

    PubMed

    Hwee, Darren T; Baehr, Leslie M; Philp, Andrew; Baar, Keith; Bodine, Sue C

    2014-02-01

    Age-related loss of muscle mass occurs to varying degrees in all individuals and has a detrimental effect on morbidity and mortality. Muscle RING Finger 1 (MuRF1), a muscle-specific E3 ubiquitin ligase, is believed to mediate muscle atrophy through the ubiquitin proteasome system (UPS). Deletion of MuRF1 (KO) in mice attenuates the loss of muscle mass following denervation, disuse, and glucocorticoid treatment; however, its role in age-related muscle loss is unknown. In this study, skeletal muscle from male wild-type (WT) and MuRF1 KO mice was studied up to the age of 24 months. Muscle mass and fiber cross-sectional area decreased significantly with age in WT, but not in KO mice. In aged WT muscle, significant decreases in proteasome activities, especially 20S and 26S β5 (20-40% decrease), were measured and were associated with significant increases in the maladaptive endoplasmic reticulum (ER) stress marker, CHOP. Conversely, in aged MuRF1 KO mice, 20S or 26S β5 proteasome activity was maintained or decreased to a lesser extent than in WT mice, and no increase in CHOP expression was measured. Examination of the growth response of older (18 months) mice to functional overload revealed that old WT mice had significantly less growth relative to young mice (1.37- vs. 1.83-fold), whereas old MuRF1 KO mice had a normal growth response (1.74- vs. 1.90-fold). These data collectively suggest that with age, MuRF1 plays an important role in the control of skeletal muscle mass and growth capacity through the regulation of cellular stress. © 2013 the Anatomical Society and John Wiley & Sons Ltd.

  1. Sarcocystis jamaicensis n. sp., from Red-Tailed Hawks (Buteo jamaicensis) Definitive Host and IFN-γ Gene Knockout Mice as Experimental Intermediate Host.

    PubMed

    Verma, S K; von Dohlen, A Rosypal; Mowery, J D; Scott, D; Rosenthal, B M; Dubey, J P; Lindsay, D S

    2017-10-01

    Here, we report a new species of Sarcocystis with red-tailed hawk (RTH, Buteo jamaicensis) as the natural definitive host and IFN-γ gene knockout (KO) mice as an experimental intermediate host in which sarcocysts form in muscle. Two RTHs submitted to the Carolina Raptor Center, Huntersville, North Carolina, were euthanized because they could not be rehabilitated and released. Fully sporulated 12.5 × 9.9-μm sized sporocysts were found in intestinal scrapings of both hawks. Sporocysts were orally fed to laboratory-reared outbred Swiss Webster mice (SW, Mus musculus) and also to KO mice. The sporocysts were infective for KO mice but not for SW mice. All SW mice remained asymptomatic, and neither schizonts nor sarcocysts were found in any SW mice euthanized on days 54, 77, 103 (n = 2) or 137 post-inoculation (PI). The KO mice developed neurological signs and were necropsied between 52 to 68 days PI. Schizonts/merozoites were found in all KO mice euthanized on days 52, 55 (n = 3), 59, 61 (n = 2), 66, and 68 PI and they were confined to the brain. The predominant lesion was meningoencephalitis characterized by perivascular cuffs, granulomas, and necrosis of the neural tissue. The schizonts/merozoites were located in neural tissue and were apparently extravascular. Brain homogenates from infected KO mice were infective to KO mice by subcutaneous inoculation and when seeded on to CV-1 cells. Microscopic sarcocysts were found in skeletal muscles of 5 of 8 KO mice euthanized between 55-61 days PI. Only a few sarcocysts were detected. Sarcocysts were microscopic, up to 3.5 mm long. When viewed with light microscopy, the sarcocyst wall appeared thin (<1 μm thick) and smooth. By transmission electron microscopy, the sarcocyst wall classified as "type 1j" (new designation). Molecular characterization using 18S rRNA, 28S rRNA, ITS-1, and cox1 genes revealed a close relationship with Sarcocystis microti and Sarcocystis glareoli; both species infect birds as definitive hosts

  2. Aberrant fatty acid metabolism in skeletal muscle contributes to insulin resistance in zinc transporter 7 (Znt7)-knockout mice.

    PubMed

    Huang, Liping; Tepaamorndech, Surapun; Kirschke, Catherine P; Newman, John W; Keyes, William R; Pedersen, Theresa L; Dumnil, Jureeporn

    2018-03-19

    ZnT7 (Slc30a7) is a widely expressed zinc transporter involved in sequestration of zinc into the Golgi apparatus and vesicular compartments. Znt7-knockout (KO) mice are mildly zinc deficient and lean. Despite their lean phenotype, adult male Znt7-KO mice are prone to insulin resistance. We hypothesized that fat partitioning from adipose to non-adipose tissues causes insulin resistance in Znt7-KO mice. Here, we used biological and biochemical methods including fatty acid and oxylipin profiling, electron microscopy, immunohistochemistry, quantitative RT-PCR, and Western blot analysis to identify the underlying mechanism of insulin resistance in Znt7-KO mice. We found that insulin resistance in this model was primarily associated with increased intracellular fatty acid levels in the skeletal muscle, which promoted intracellular lipid accumulation and production of bioactive lipid mediators, such as 12,13-dihydroxyoctadecanoic acid (12,13-DiHOME) and 12-hydroxyeicosatetraenoic acid (12-HETE). The expression of fatty acid-binding protein 3 (Fabp3) was dramatically up-regulated in the Znt7-KO muscle cells accompanied by increased expression of Cd36, Slc27a1, and Slc27a4, the three major fatty acid transporters in the skeletal muscle. We also demonstrated that Znt7-KO muscle cells had increased fatty acid oxidative capacity, indicated by enlarged mitochondria and increased mRNA or protein expression of key enzymes involved in the fatty acid mitochondrial shuttle and β-oxidation. We conclude that increased fatty acid uptake in the Znt7-KO skeletal muscle is a key factor that contributes to the excessive intracellular lipid deposit and elevated production of bioactive lipid mediators. These mediators may play pivotal roles in oxidative stress and inflammation, leading to insulin resistance. Copyright © 2018, The American Society for Biochemistry and Molecular Biology.

  3. Orexin knockout mice exhibit impaired spatial working memory.

    PubMed

    Dang, Ruozhi; Chen, Qiuhan; Song, Jie; He, Chao; Zhang, Jun; Xia, Jianxia; Hu, Zhian

    2018-03-06

    Orexins play a crucial role in the maintenance of arousal and are involved in the modulation of diverse physiological process, including cognitive function. Recent data have suggested that orexins are involved in learning and memory processes. The purpose of this study was to assess the effects of orexin deficiency on working memory. A delayed non-matching-to-place T-maze task was used to evaluate spatial working memory in mice lacking orexin prepro-peptide (orexin knockout; KO) and wild-type controls. We demonstrated that the number of correct choices in the orexin KO mice became lower than that of the controls over training. In an object exploration task, the controls explored the displaced object more than the mutants did, whereas this difference was not observed for the nondisplaced objects in either group. The orexin KO mice showed locomotor activity comparable to the control mice in terms of total distance traveled across training in both the object exploration task and the open field test. These findings indicate that the orexin system plays an important role in working memory of spatial cues. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Contribution of P2X4 receptors to ethanol intake in male C57BL/6 mice

    PubMed Central

    Wyatt, Letisha R.; Finn, Deborah A.; Khoja, Sheraz; Yardley, Megan M; Asatryan, Liana; Alkana, Ronald L.; Davies, Daryl L.

    2014-01-01

    P2X receptors (P2XRs) are a family of cation-permeable ligand-gated ion channels activated by synaptically released extracellular ATP. The P2X4 subtype is abundantly expressed in the CNS and is sensitive to low intoxicating ethanol concentrations. Genetic meta-analyses identified the p2rx4 gene as a candidate gene for innate alcohol intake and/or preference. The current study used mice lacking the p2rx4 gene (knockout, KO) and wildtype (WT) C57BL/6 controls to test the hypothesis that P2X4Rs contribute to ethanol intake. The early acquisition and early maintenance phases of ethanol intake were measured with three different drinking procedures. Further, we tested the effects of ivermectin (IVM), a drug previously shown to reduce ethanol’s effects on P2X4Rs and to reduce ethanol intake and preference, for its ability to differentially alter stable ethanol intake in KO and WT mice. Depending on the procedure and the concentration of the ethanol solution, ethanol intake was transiently increased in P2X4R KO versus WT mice during the acquisition of 24-hr and limited access ethanol intake. IVM significantly reduced ethanol intake in P2X4R KO and WT mice, but the degree of reduction was 50% less in the P2X4R KO mice. Western blot analysis identified significant changes in -γ aminobutyric acidA receptor (GABAAR) α1 subunit expression in brain regions associated with the regulation of ethanol behaviors in P2X4R KO mice. These findings add to evidence that P2X4Rs contribute to ethanol intake and indicate that there is a complex interaction between P2X4Rs, ethanol, and other neurotransmitter receptor systems. PMID:24671605

  5. Conditional Deletion of Fgfr3 in Chondrocytes leads to Osteoarthritis-like Defects in Temporomandibular Joint of Adult Mice

    PubMed Central

    Zhou, Siru; Xie, Yangli; Li, Wei; Huang, Junlan; Wang, Zuqiang; Tang, Junzhou; Xu, Wei; Sun, Xianding; Tan, Qiaoyan; Huang, Shuo; Luo, Fengtao; Xu, Meng; Wang, Jun; Wu, Tingting; chen, Liang; Chen, Hangang; Su, Nan; Du, Xiaolan; Shen, Yue; Chen, Lin

    2016-01-01

    Osteoarthritis (OA) in the temporomandibular joint (TMJ) is a common degenerative disease in adult, which is characterized by progressive destruction of the articular cartilage. To investigate the role of FGFR3 in the homeostasis of TMJ cartilage during adult stage, we generated Fgfr3f/f; Col2a1-CreERT2 (Fgfr3 cKO) mice, in which Fgfr3 was deleted in chondrocytes at 2 months of age. OA-like defects were observed in Fgfr3 cKO TMJ cartilage. Immunohistochemical staining and quantitative real-time PCR analyses revealed a significant increase in expressions of COL10, MMP13 and AMAMTS5. In addition, there was a sharp increase in chondrocyte apoptosis at the Fgfr3 cKO articular surface, which was accompanied by a down-regulation of lubricin expression. Importantly, the expressions of RUNX2 and Indian hedgehog (IHH) were up-regulated in Fgfr3 cKO TMJ. Primary Fgfr3 cKO chondrocytes were treated with IHH signaling inhibitor, which significantly reduced expressions of Runx2, Col10, Mmp13 and Adamts5. Furthermore, the IHH signaling inhibitor partially alleviated OA-like defects in the TMJ of Fgfr3 cKO mice, including restoration of lubricin expression and improvement of the integrity of the articular surface. In conclusion, our study proposes that FGFR3/IHH signaling pathway plays a critical role in maintaining the homeostasis of TMJ articular cartilage during adult stage. PMID:27041063

  6. Regulation of Prolactin in Mice with Altered Hypothalamic Melanocortin Activity

    PubMed Central

    Dutia, Roxanne; Kim, Andrea J.; Mosharov, Eugene; Savontaus, Eriika; Chua, Streamson C.; Wardlaw, Sharon L.

    2012-01-01

    This study used two mouse models with genetic manipulation of the melanocortin system to investigate prolactin regulation. Mice with overexpression of the melanocortin receptor (MC-R) agonist, α-melanocyte-stimulating hormone (Tg-MSH) or deletion of the MC-R antagonist agouti-related protein (AgRP KO) were studied. Male Tg-MSH mice had lower blood prolactin levels at baseline (2.9±0.3 vs 4.7±0.7 ng/ml) and after restraint stress(68 ±6.5 vs 117±22 ng/ml) versus WT (p<0.05); however, pituitary prolactin content was not different. Blood prolactin was also decreased in male AgRP KO mice at baseline (4.2±0.5 vs 7.6±1.3 ng/ml) and after stress (60±4.5 vs 86.1±5.7 ng/ml) vs WT (p <0.001). Pituitary prolactin content was lower in male AgRP KO mice (4.3±0.3 vs 6.7±0.5 μg/pituitary, p <0.001) versus WT. No differences in blood or pituitary prolactin levels were observed in female AgRP KO mice versus WT. Hypothalamic dopamine activity was assessed as the potential mechanism responsible for changes in prolactin levels. Hypothalamic tyrosine hydroxylase mRNA was measured in both genetic models versus WT mice and hypothalamic dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) content were measured in male AgRP KO and WT mice but neither were significantly different. However, these results do not preclude changes in dopamine activity as dopamine turnover was not directly investigated. This is the first study to show that baseline and stress-induced prolactin release and pituitary prolactin content are reduced in mice with genetic alterations of the melanocortin system and suggests that changes in hypothalamic melanocortin activity may be reflected in measurements of serum prolactin levels. PMID:22800691

  7. Traumatic brain injury enhances neuroinflammation and lesion volume in caveolin deficient mice.

    PubMed

    Niesman, Ingrid R; Schilling, Jan M; Shapiro, Lee A; Kellerhals, Sarah E; Bonds, Jacqueline A; Kleschevnikov, Alexander M; Cui, Weihua; Voong, April; Krajewski, Stan; Ali, Sameh S; Roth, David M; Patel, Hemal H; Patel, Piyush M; Head, Brian P

    2014-03-03

    Traumatic brain injury (TBI) enhances pro-inflammatory responses, neuronal loss and long-term behavioral deficits. Caveolins (Cavs) are regulators of neuronal and glial survival signaling. Previously we showed that astrocyte and microglial activation is increased in Cav-1 knock-out (KO) mice and that Cav-1 and Cav-3 modulate microglial morphology. We hypothesized that Cavs may regulate cytokine production after TBI. Controlled cortical impact (CCI) model of TBI (3 m/second; 1.0 mm depth; parietal cortex) was performed on wild-type (WT; C57Bl/6), Cav-1 KO, and Cav-3 KO mice. Histology and immunofluorescence microscopy (lesion volume, glia activation), behavioral tests (open field, balance beam, wire grip, T-maze), electrophysiology, electron paramagnetic resonance, membrane fractionation, and multiplex assays were performed. Data were analyzed by unpaired t tests or analysis of variance (ANOVA) with post-hoc Bonferroni's multiple comparison. CCI increased cortical and hippocampal injury and decreased expression of MLR-localized synaptic proteins (24 hours), enhanced NADPH oxidase (Nox) activity (24 hours and 1 week), enhanced polysynaptic responses (1 week), and caused hippocampal-dependent learning deficits (3 months). CCI increased brain lesion volume in both Cav-3 and Cav-1 KO mice after 24 hours (P < 0.0001, n = 4; one-way ANOVA). Multiplex array revealed a significant increase in expression of IL-1β, IL-9, IL-10, KC (keratinocyte chemoattractant), and monocyte chemoattractant protein 1 (MCP-1) in ipsilateral hemisphere and IL-9, IL-10, IL-17, and macrophage inflammatory protein 1 alpha (MIP-1α) in contralateral hemisphere of WT mice after 4 hours. CCI increased IL-2, IL-6, KC and MCP-1 in ipsilateral and IL-6, IL-9, IL-17 and KC in contralateral hemispheres in Cav-1 KO and increased all 10 cytokines/chemokines in both hemispheres except for IL-17 (ipsilateral) and MIP-1α (contralateral) in Cav-3 KO (versus WT CCI). Cav-3 KO CCI showed increased IL-1β, IL-9

  8. Mechanism of hyperphagia contributing to obesity in brain-derived neurotrophic factor knockout mice.

    PubMed

    Fox, E A; Biddinger, J E; Jones, K R; McAdams, J; Worman, A

    2013-01-15

    Global-heterozygous and brain-specific homozygous knockouts (KOs) of brain-derived neurotrophic factor (BDNF) cause late- and early-onset obesity, respectively, both involving hyperphagia. Little is known about the mechanism underlying this hyperphagia or whether BDNF loss from peripheral tissues could contribute to overeating. Since global-homozygous BDNF-KO is perinatal lethal, a BDNF-KO that spared sufficient brainstem BDNF to support normal health was utilized to begin to address these issues. Meal pattern and microstructure analyses suggested overeating of BDNF-KO mice was mediated by deficits in both satiation and satiety that resulted in increased meal size and frequency and implicated a reduction of vagal signaling from the gut to the brain. Meal-induced c-Fos activation in the nucleus of the solitary tract, a more direct measure of vagal afferent signaling, however, was not decreased in BDNF-KO mice, and thus was not consistent with a vagal afferent role. Interestingly though, meal-induced c-Fos activation was increased in the dorsal motor nucleus of the vagus nerve (DMV) of BDNF-KO mice. This could imply that augmentation of vago-vagal digestive reflexes occurred (e.g., accommodation), which would support increased meal size and possibly increased meal number by reducing the increase in intragastric pressure produced by a given amount of ingesta. Additionally, vagal sensory neuron number in BDNF-KO mice was altered in a manner consistent with the increased meal-induced activation of the DMV. These results suggest reduced BDNF causes satiety and satiation deficits that support hyperphagia, possibly involving augmentation of vago-vagal reflexes mediated by central pathways or vagal afferents regulated by BDNF levels. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

  9. Requirement for Ca2+/calmodulin-dependent kinase II in the transition from pressure overload-induced cardiac hypertrophy to heart failure in mice.

    PubMed

    Ling, Haiyun; Zhang, Tong; Pereira, Laetitia; Means, Christopher Kable; Cheng, Hongqiang; Gu, Yusu; Dalton, Nancy D; Peterson, Kirk L; Chen, Ju; Bers, Donald; Brown, Joan Heller; Heller Brown, Joan

    2009-05-01

    Ca2+/calmodulin-dependent kinase II (CaMKII) has been implicated in cardiac hypertrophy and heart failure. We generated mice in which the predominant cardiac isoform, CaMKIIdelta, was genetically deleted (KO mice), and found that these mice showed no gross baseline changes in ventricular structure or function. In WT and KO mice, transverse aortic constriction (TAC) induced comparable increases in relative heart weight, cell size, HDAC5 phosphorylation, and hypertrophic gene expression. Strikingly, while KO mice showed preserved hypertrophy after 6-week TAC, CaMKIIdelta deficiency significantly ameliorated phenotypic changes associated with the transition to heart failure, such as chamber dilation, ventricular dysfunction, lung edema, cardiac fibrosis, and apoptosis. The ratio of IP3R2 to ryanodine receptor 2 (RyR2) and the fraction of RyR2 phosphorylated at the CaMKII site increased significantly during development of heart failure in WT mice, but not KO mice, and this was associated with enhanced Ca2+ spark frequency only in WT mice. We suggest that CaMKIIdelta contributes to cardiac decompensation by enhancing RyR2-mediated sarcoplasmic reticulum Ca2+ leak and that attenuating CaMKIIdelta activation can limit the progression to heart failure.

  10. Normal Performance of Fmr1 Mice on a Touchscreen Delayed Nonmatching to Position Working Memory Task123

    PubMed Central

    Hayes, Jane; Pride, Michael; Silverman, Jill L.; Crawley, Jacqueline N.

    2016-01-01

    Abstract Fragile X syndrome is a neurodevelopmental disorder characterized by mild-to-severe cognitive deficits. The complete absence of Fmr1 and its protein product in the mouse model of fragile X (Fmr1 KO) provides construct validity. A major conundrum in the field is the remarkably normal performance of Fmr1 mice on cognitive tests in most reports. One explanation may be insufficiently challenging cognitive testing procedures. Here we developed a delayed nonmatching to position touchscreen task to test the hypothesis that paradigms placing demands on working memory would reveal robust and replicable cognitive deficits in the Fmr1 KO mouse. We first tested Fmr1 KO mice (Fmr1) and their wild-type (WT) littermates in a simple visual discrimination task, followed by assessment of reversal learning. We then tested Fmr1 and WT mice in a new touchscreen nonmatch to position task and subsequently challenged their working memory abilities by adding delays, representing a higher cognitive load. The performance by Fmr1 KO mice was equal to WTs on both touchscreen tasks. Last, we replicated previous reports of normal performance by Fmr1 mice on Morris water maze spatial navigation and reversal. These results indicate that, while the Fmr1 mouse model effectively recapitulates many molecular and cellular aspects of fragile X syndrome, the cognitive profile of Fmr1 mice generally does not recapitulate the primary cognitive deficits in the human syndrome, even when diverse and challenging tasks are imposed. PMID:27022628

  11. Loss of ACE2 Exaggerates High-Calorie Diet–Induced Insulin Resistance by Reduction of GLUT4 in Mice

    PubMed Central

    Takeda, Masao; Yamamoto, Koichi; Takemura, Yukihiro; Takeshita, Hikari; Hongyo, Kazuhiro; Kawai, Tatsuo; Hanasaki-Yamamoto, Hiroko; Oguro, Ryosuke; Takami, Yoichi; Tatara, Yuji; Takeya, Yasushi; Sugimoto, Ken; Kamide, Kei; Ohishi, Mitsuru; Rakugi, Hiromi

    2013-01-01

    ACE type 2 (ACE2) functions as a negative regulator of the renin-angiotensin system by cleaving angiotensin II (AII) into angiotensin 1–7 (A1–7). This study assessed the role of endogenous ACE2 in maintaining insulin sensitivity. Twelve-week-old male ACE2 knockout (ACE2KO) mice had normal insulin sensitivities when fed a standard diet. AII infusion or a high-fat, high-sucrose (HFHS) diet impaired glucose tolerance and insulin sensitivity more severely in ACE2KO mice than in their wild-type (WT) littermates. The strain difference in glucose tolerance was not eliminated by an AII receptor type 1 (AT1) blocker but was eradicated by A1–7 or an AT1 blocker combined with the A1–7 inhibitor (A779). The expression of GLUT4 and a transcriptional factor, myocyte enhancer factor (MEF) 2A, was dramatically reduced in the skeletal muscles of the standard diet–fed ACE2KO mice. The expression of GLUT4 and MEF2A was increased by A1–7 in ACE2KO mice and decreased by A779 in WT mice. A1–7 enhanced upregulation of MEF2A and GLUT4 during differentiation of myoblast cells. In conclusion, ACE2 protects against high-calorie diet–induced insulin resistance in mice. This mechanism may involve the transcriptional regulation of GLUT4 via an A1–7–dependent pathway. PMID:22933108

  12. Calcium oxalate crystal deposition in kidneys of hypercalciuric mice with disrupted type IIa sodium-phosphate cotransporter

    PubMed Central

    Khan, Saeed R.; Glenton, Patricia A.

    2013-01-01

    The most common theories about the pathogenesis of idiopathic kidney stones consider precipitation of calcium phosphate (CaP) within the kidneys critical for the development of the disease. We decided to test the hypothesis that a CaP substrate can promote the deposition of calcium oxalate (CaOx) in the kidneys. Experimental hyperoxaluria was induced by feeding glyoxylate to male mice with knockout (KO) of NaPi IIa (Npt2a), a sodium-phosphate cotransporter. Npt2a KO mice are hypercalciuric and produce CaP deposits in their renal tubules. Experimental hyperoxaluria led to CaOx crystalluria in both the hypercalciuric KO mice and the normocalciuric control B6 mice. Only the KO mice produced CaOx crystal deposits in their kidneys, but the CaOx crystals deposited separately from the CaP deposits. Perhaps CaP deposits were not available for a CaOx overgrowth. These results also validate earlier animal model observations that showed that CaP substrate is not required for renal deposition of CaOx and that other factors, such as local supersaturation, may be involved. The absence of CaOx deposition in the B6 mice despite extreme hyperoxaluria also signifies the importance of both calcium and oxalate in the development of CaOx nephrolithiasis. PMID:18337544

  13. Abolished thermal and mechanical antinociception but retained visceral chemical antinociception induced by butorphanol in μ-opioid receptor knockout mice

    PubMed Central

    Ide, Soichiro; Minami, Masabumi; Ishihara, Kumatoshi; Uhl, George R.; Satoh, Masamichi; Sora, Ichiro; Ikeda, Kazutaka

    2012-01-01

    Butorphanol is hypothesized to induce analgesia via opioid pathways, although the precise mechanisms for its effects remain unknown. In this study, we investigated the role of the μ-opioid receptor (MOP) in thermal, mechanical, and visceral chemical antinociception induced by butorphanol using MOP knockout (KO) mice. Butorphanol-induced thermal antinociception, assessed by the hot-plate and tail-flick tests, was significantly reduced in heterozygous and abolished in homozygous MOP-KO mice compared with wildtype mice. The results obtained from our butorphanol-induced mechanical antinociception experiments, assessed by the Randall-Selitto test, were similar to the results obtained from the thermal antinociception experiments in these mice. Interestingly, however, butorphanol retained its ability to induce significant visceral chemical antinociception, assessed by the writhing test, in homozygous MOP-KO mice. The butorphanol-induced visceral chemical antinociception that was retained in homozygous MOP-KO mice was completely blocked by pretreatment with nor-binaltorphimine, a κ-opioid receptor (KOP) antagonist. In vitro binding and cyclic adenosine monophosphate assays also showed that butorphanol possessed higher affinity for KOPs and MOPs than for δ-opioid receptors. These results molecular pharmacologically confirmed previous studies implicating MOPs, and partially KOPs, in mediating butorphanol-induced analgesia. PMID:18417173

  14. Ameliorating effect of histamine on impairment of cued fear extinction induced by morphine withdrawal in histidine decarboxylase gene knockout mice.

    PubMed

    Gong, Ying-xia; Shou, Wen-ting; Feng, Bo; Zhang, Wei-ping; Wang, Hui-juan; Ohtsu, Hiroshi; Chen, Zhong

    2010-11-01

    Histamine plays an important role in morphine addiction and memory-dependent behavior. However, little is known about the effect of histamine on the impairment of memory after morphine withdrawal. This study was designed to investigate the effect of histamine on memory impairment induced by morphine withdrawal in histidine decarboxylase knockout (HDC-KO) and wild-type (WT) mice. WT and HDC-KO mice were given subcutaneous morphine or saline twice daily for 5 consecutive days. The mice received a cued or contextual fear conditioning session 7 days after the last injection. During subsequent days, mice received 4 cued or contextual extinction sessions (one session per day). Western blot was used to assess extracellular signal-regulated kinase (ERK) phosphorylation in the amygdala and hippocampus. Morphine withdrawal did not affect the acquisition of cued or contextual fear responses. It impaired cued but not contextual fear extinction. The acquisition of cued and contextual fear responses was accelerated in HDC-KO mice. Histamine deficiency aggravated the impairment of cued fear extinction induced by morphine withdrawal, whereas histamine (icv, 5 μg/mouse) reversed this effect. Morphine withdrawal decreased ERK phosphorylation in the amygdala after cued fear extinction, especially in HDC-KO mice. These results suggest that morphine withdrawal specifically impairs cued fear extinction and histamine ameliorates this impairment. Its action might be mediated by the modulation of ERK phosphorylation in the amygdala. Histamine should be explored for possible roles in the prevention or treatment of morphine abuse and relapse.

  15. Koala retrovirus genotyping analyses reveal a low prevalence of KoRV-A in Victorian koalas and an association with clinical disease.

    PubMed

    Legione, Alistair R; Patterson, Jade L S; Whiteley, Pam; Firestone, Simon M; Curnick, Megan; Bodley, Kate; Lynch, Michael; Gilkerson, James R; Sansom, Fiona M; Devlin, Joanne M

    2017-02-01

    Koala retrovirus (KoRV) is undergoing endogenization into the genome of koalas in Australia, providing an opportunity to assess the effect of retrovirus infection on the health of a population. The prevalence of KoRV in north-eastern Australia (Queensland and New South Wales) is 100 %, whereas previous preliminary investigations in south-eastern Australia (Victoria) suggested KoRV is present at a lower prevalence, although the values have varied widely. Here, we describe a large study of free-ranging koalas in Victoria to estimate the prevalence of KoRV and assess the clinical significance of KoRV infection in wild koalas. Blood or spleen samples from 648 koalas where tested for KoRV provirus, and subsequently genotyped, using PCRs to detect the pol and env genes respectively. Clinical data was also recorded where possible and analysed in comparison to infection status. The prevalence of KoRV was 24.7 % (160/648). KoRV-A was detected in 141/160 cases, but KoRV-B, a genotype associated with neoplasia in captive koalas, was not detected. The genotype in 19 cases could not be determined. Genomic differences between KoRV in Victoria and type strains may have impacted genotyping. Factors associated with KoRV infection, based on multivariable analysis, were low body condition score, region sampled, and 'wet bottom' (a staining of the fur around the rump associated with chronic urinary incontinence). Koalas with wet bottom were nearly twice as likely to have KoRV provirus detected than those without wet bottom (odds ratio=1.90, 95 % confidence interval 1.21, 2.98). Our findings have important implications for the conservation of this iconic species, particularly regarding translocation potential of Victorian koalas.

  16. In vivo ketogenic diet treatment attenuates pathologic sharp waves and high frequency oscillations in in vitro hippocampal slices from epileptic Kv 1.1α knockout mice.

    PubMed

    Simeone, Timothy A; Samson, Kaeli K; Matthews, Stephanie A; Simeone, Kristina A

    2014-05-01

    The ketogenic diet (KD) is an effective therapy for pediatric refractory epilepsies; however, whether the KD changes the pathologic network oscillations generated by an epileptic brain remains unknown. We have reported that hippocampal CA3 regions of epileptic Kv1.1α knockout (KO) mice generate pathologic sharp waves (SPWs) and high-frequency oscillations (HFOs) that have higher incidence, longer duration, and fast ripples compared to wild-type (WT). Synaptic activity of hyperexcitable KO mossy fibers significantly decreased CA3 principal cell spike-timing reliability, which contributed to this network pathology. In addition, we have demonstrated that the KD reduces seizures by 75% in KO mice. Here, we determined whether 10- to 14-day in vivo KD treatment exerts disease-modifying effects that alter the spontaneous SPW-HFO complexes generated by the hippocampal CA3 region of KO mice in vitro using extracellular multielectrode array recordings. We found that KD treatment significantly attenuated the pathologic features of KO SPWs and ripples and reduced the incidence of fast ripples. The KD also improved spike-timing reliability of KO CA3 principal cells, decreased mossy fiber excitability, increased mossy fiber-CA3 paired-pulse ratios, and reduced coupling of field excitatory postsynaptic potentials and population spikes in the CA3 region. Collectively, these data indicate that KD treatment modulates CA3-generated pathologic oscillations by dampening hyperactive mossy fiber synapses. Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.

  17. [Atorvastatin inhibits the atherosclerotic lesion induced by tumor necrosis factor-like weak inducer of apoptosis in apolipoprotein E deficient mice].

    PubMed

    Fernández-Laso, Valvanera; Sastre, Cristina; Egido, Jesús; Martín-Ventura, Jose L; Blanco-Colio, Luis M

    2015-01-01

    Interaction of tumor necrosis factor-like weak inducer of apoptosis (TWEAK) with its receptor Fn14 accelerates atherosclerotic plaque development in ApoE deficient mice (ApoE KO). In this work, an analysis has been made on the effect of an HMG-CoA reductase inhibitor, atorvastatin, on atherosclerotic plaque development accelerated by TWEAK in ApoE KO mice. Eight week-old ApoE KO mice were fed with a high cholesterol diet for 4 weeks. The animals were then randomized into 3 groups: mice injected i.p. with saline, recombinant TWEAK (10 μg/kg/twice a week), or recombinant TWEAK plus atorvastatin (1 mg/kg/day) for 4 weeks. The lesion size, cellular composition, lipid and collagen content were analyzed, as well as inflammatory response in atherosclerotic plaques present in aortic root of mice. TWEAK treated mice showed an increase in atherosclerotic plaque size, as well as in collagen/lipid ratio compared with control mice. In addition, macrophage content, MCP-1 and RANTES expression, and NF-κB activation were augmented in atherosclerotic plaques present in aortic root of TWEAK treated mice compared with control mice. Treatment with atorvastatin prevented all these changes induced by TWEAK in atherosclerotic lesions. Atorvastatin treatment also decreased Fn14 expression in the atherosclerotic plaques of ApoE KO mice. Atorvastatin prevents the pro-atherogenic effects induced by TWEAK in ApoE KO mice, which could be related to the inhibition of Fn14 expression. The results of this study provide new information on the beneficial effects of statin treatment in cardiovascular diseases. Copyright © 2014 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  18. Inhibitory Effects of North American Wild Rice on Monocyte Adhesion and Inflammatory Modulators in Low-Density Lipoprotein Receptor-Knockout Mice.

    PubMed

    Moghadasian, Mohammed H; Zhao, Ruozhi; Ghazawwi, Nora; Le, Khuong; Apea-Bah, Franklin B; Beta, Trust; Shen, Garry X

    2017-10-18

    The present study examined the effects of wild rice on monocyte adhesion, inflammatory and fibrinolytic mediators in low-density lipoprotein receptor-knockout (LDLr-KO) mice. Male LDLr-KO mice received a cholesterol (0.06%, w/w)-supplemented diet with or without white or wild rice (60%, w/w) for 20 weeks. White rice significantly increased monocyte adhesion and abundances of monocyte chemoattractant protein-1, tissue necrosis factor-α, intracellular cell adhesion molecule-1, plasminogen activator inhibitor-1, urokinase plasminogen activator (uPA), and uPA receptor in aortae and hearts of LDLr-KO mice compared to the control diet. Wild rice inhibited monocyte adhesion to the aorta, atherosclerosis, and abundances of the inflammatory and fibrinolytic regulators in the cardiovascular tissue of LDLr-KO mice compared to white rice. White or wild rice did not significantly alter the levels of cholesterol, triglycerides, or antioxidant enzymes in plasma. The anti-atherosclerotic effect of wild rice may result from its inhibition on monocyte adhesion and inflammatory modulators in LDLr-KO mice.

  19. Loss of AMP-activated protein kinase induces mitochondrial dysfunction and proinflammatory response in unstimulated Abcd1-knockout mice mixed glial cells.

    PubMed

    Singh, Jaspreet; Suhail, Hamid; Giri, Shailendra

    2015-01-01

    X-linked adrenoleukodystrophy (X-ALD) is caused by mutations and/or deletions in the ABCD1 gene. Similar mutations/deletions can give rise to variable phenotypes ranging from mild adrenomyeloneuropathy (AMN) to inflammatory fatal cerebral adrenoleukodystrophy (ALD) via unknown mechanisms. We recently reported the loss of the anti-inflammatory protein adenosine monophosphate activated protein kinase (AMPKα1) exclusively in ALD patient-derived cells. X-ALD mouse model (Abcd1-knockout (KO) mice) mimics the human AMN phenotype and does not develop the cerebral inflammation characteristic of human ALD. In this study we document that AMPKα1 levels in vivo (in brain cortex and spinal cord) and in vitro in Abcd1-KO mixed glial cells are similar to that of wild type mice. Deletion of AMPKα1 in the mixed glial cells of Abcd1-KO mice induced spontaneous mitochondrial dysfunction (lower oxygen consumption rate and ATP levels). Mitochondrial dysfunction in ALD patient-derived cells and in AMPKα1-deleted Abcd1-KO mice mixed glial cells was accompanied by lower levels of mitochondrial complex (1-V) subunits. More importantly, AMPKα1 deletion induced proinflammatory inducible nitric oxide synthase levels in the unstimulated Abcd1-KO mice mixed glial cells. Taken together, this study provides novel direct evidence for a causal role for AMPK loss in the development of mitochondrial dysfunction and proinflammatory response in X-ALD.

  20. Loss of AMP-Activated Protein Kinase Induces Mitochondrial Dysfunction and Proinflammatory Response in Unstimulated Abcd1-Knockout Mice Mixed Glial Cells

    PubMed Central

    Suhail, Hamid; Giri, Shailendra

    2015-01-01

    X-linked adrenoleukodystrophy (X-ALD) is caused by mutations and/or deletions in the ABCD1 gene. Similar mutations/deletions can give rise to variable phenotypes ranging from mild adrenomyeloneuropathy (AMN) to inflammatory fatal cerebral adrenoleukodystrophy (ALD) via unknown mechanisms. We recently reported the loss of the anti-inflammatory protein adenosine monophosphate activated protein kinase (AMPKα1) exclusively in ALD patient-derived cells. X-ALD mouse model (Abcd1-knockout (KO) mice) mimics the human AMN phenotype and does not develop the cerebral inflammation characteristic of human ALD. In this study we document that AMPKα1 levels in vivo (in brain cortex and spinal cord) and in vitro in Abcd1-KO mixed glial cells are similar to that of wild type mice. Deletion of AMPKα1 in the mixed glial cells of Abcd1-KO mice induced spontaneous mitochondrial dysfunction (lower oxygen consumption rate and ATP levels). Mitochondrial dysfunction in ALD patient-derived cells and in AMPKα1-deleted Abcd1-KO mice mixed glial cells was accompanied by lower levels of mitochondrial complex (1-V) subunits. More importantly, AMPKα1 deletion induced proinflammatory inducible nitric oxide synthase levels in the unstimulated Abcd1-KO mice mixed glial cells. Taken together, this study provides novel direct evidence for a causal role for AMPK loss in the development of mitochondrial dysfunction and proinflammatory response in X-ALD. PMID:25861159

  1. Hepatic and muscular effects of different dietary fat content in VLCAD deficient mice.

    PubMed

    Primassin, Sonja; Tucci, Sara; Spiekerkoetter, Ute

    2011-12-01

    Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is the most common long-chain fatty acid oxidation defect presenting with heterogeneous clinical phenotypes. Dietary fat plays a crucial role in disease pathogenesis and fat restriction is a common treatment measure. We here investigate the hepatic and muscular effects of a fat-enriched and a fat-restricted diet. VLCAD knock-out (KO) and wild-type (WT) mice are subjected to a fat-rich (10.6%), a fat-reduced (2.6%) or a regular mouse diet (5.1%) for 5 weeks. Analyses are performed at rest and after one hour exercise on a treadmill. Acylcarnitines in muscle as well as lipid and glycogen content in muscle and liver are quantified. Expression of genes involved in lipogenesis is measured by Real-Time-PCR. At rest, VLCAD KO mice develop no clinical phenotype with all three diets, but importantly VLCAD KO mice cannot perform one hour exercise as compared to WT, this is especially apparent in mice with a fat-reduced diet. Moreover, changes in dietary fat content induce a significant increase in muscular long-chain acylcarnitines and hepatic lipid content in VLCAD KO mice after exercise. A fat-reduced diet up-regulates hepatic lipogenesis at rest. At the same time, muscular glycogen is significantly lower than in WT. We here demonstrate that a fat-reduced and carbohydrate-enriched diet does not prevent the myopathic phenotype in VLCAD KO mice. An increase in dietary fat is safe at rest with respect to the muscle but results in a significant muscular acylcarnitine increase after exercise. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Platelet amyloid precursor protein is a modulator of venous thromboembolism in mice.

    PubMed

    Canobbio, Ilaria; Visconte, Caterina; Momi, Stefania; Guidetti, Gianni Francesco; Zarà, Marta; Canino, Jessica; Falcinelli, Emanuela; Gresele, Paolo; Torti, Mauro

    2017-07-27

    The amyloid precursor protein (APP), primarily known as the precursor of amyloid peptides that accumulate in the brain of patients with Alzheimer disease, is abundant in platelets, but its physiological function remains unknown. In this study, we investigated the role of APP in hemostasis and thrombosis, using APP knockout (KO) mice. Ex vivo aggregation, secretion, and integrin αIIbβ3 inside-out activation induced by several agonists were normal in APP-deficient platelets, but the number of circulating platelets was reduced by about 20%, and their size was slightly increased. Tail bleeding time was normal, and in vivo, the absence of APP did not alter thrombus formation in the femoral artery. In contrast, in a model of vein thrombosis induced by flow restriction in the inferior vena cava, APP-KO mice, as well as chimeric mice with selective deficiency of APP in blood cells, developed much larger thrombi than control animals, and were more sensitive to embolization. Consistent with this, in a pulmonary thromboembolism model, larger vessels were occluded. APP-KO mice displayed a shorter APTT, but not PT, when measured in the presence of platelets. Moreover, the activity of factor XIa (FXIa), but not FXIIa, was higher in APP-KO mice compared with controls. APP-KO mice presented a higher number of circulating platelet-leukocyte aggregates, and neutrophils displayed a greater tendency to protrude extracellular traps, which were more strongly incorporated into venous thrombi. These results indicate that platelet APP limits venous thromboembolism through a negative regulation of both fibrin formation and neutrophil function. © 2017 by The American Society of Hematology.

  3. Ghrelin knockout mice show decreased voluntary alcohol consumption and reduced ethanol-induced conditioned place preference.

    PubMed

    Bahi, Amine; Tolle, Virginie; Fehrentz, Jean-Alain; Brunel, Luc; Martinez, Jean; Tomasetto, Catherine-Laure; Karam, Sherif M

    2013-05-01

    Recent work suggests that stomach-derived hormone ghrelin receptor (GHS-R1A) antagonism may reduce motivational aspects of ethanol intake. In the current study we hypothesized that the endogenous GHS-R1A agonist ghrelin modulates alcohol reward mechanisms. For this purpose ethanol-induced conditioned place preference (CPP), ethanol-induced locomotor stimulation and voluntary ethanol consumption in a two-bottle choice drinking paradigm were examined under conditions where ghrelin and its receptor were blocked, either using ghrelin knockout (KO) mice or the specific ghrelin receptor (GHS-R1A) antagonist "JMV2959". We showed that ghrelin KO mice displayed lower ethanol-induced CPP than their wild-type (WT) littermates. Consistently, when injected during CPP-acquisition, JMV2959 reduced CPP-expression in C57BL/6 mice. In addition, ethanol-induced locomotor stimulation was lower in ghrelin KO mice. Moreover, GHS-R1A blockade, using JMV2959, reduced alcohol-stimulated locomotion only in WT but not in ghrelin KO mice. When alcohol consumption and preference were assessed using the two-bottle choice test, both genetic deletion of ghrelin and pharmacological antagonism of the GHS-R1A (JMV2959) reduced voluntary alcohol consumption and preference. Finally, JMV2959-induced reduction of alcohol intake was only observed in WT but not in ghrelin KO mice. Taken together, these results suggest that ghrelin neurotransmission is necessary for the stimulatory effect of ethanol to occur, whereas lack of ghrelin leads to changes that reduce the voluntary intake as well as conditioned reward by ethanol. Our findings reveal a major, novel role for ghrelin in mediating ethanol behavior, and add to growing evidence that ghrelin is a key mediator of the effects of multiple abused drugs. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Pancreatic Protein Tyrosine Phosphatase 1B Deficiency Exacerbates Acute Pancreatitis in Mice.

    PubMed

    Bettaieb, Ahmed; Koike, Shinichiro; Chahed, Samah; Bachaalany, Santana; Griffey, Stephen; Sastre, Juan; Haj, Fawaz G

    2016-08-01

    Acute pancreatitis (AP) is a common and devastating gastrointestinal disorder that causes significant morbidity. The disease starts as local inflammation in the pancreas that may progress to systemic inflammation and complications. Protein tyrosine phosphatase 1B (PTP1B) is implicated in inflammatory signaling, but its significance in AP remains unclear. To investigate whether PTP1B may have a role in AP, we used pancreas PTP1B knockout (panc-PTP1B KO) mice and determined the effects of pancreatic PTP1B deficiency on cerulein- and arginine-induced acute pancreatitis. We report that PTP1B protein expression was increased in the early phase of AP in mice and rats. In addition, histological analyses of pancreas samples revealed enhanced features of AP in cerulein-treated panc-PTP1B KO mice compared with controls. Moreover, cerulein- and arginine-induced serum amylase and lipase were significantly higher in panc-PTP1B KO mice compared with controls. Similarly, pancreatic mRNA and serum concentrations of the inflammatory cytokines IL-1B, IL-6, and tumor necrosis factor-α were increased in panc-PTP1B KO mice compared with controls. Furthermore, panc-PTP1B KO mice exhibited enhanced cerulein- and arginine-induced NF-κB inflammatory response accompanied with increased mitogen-activated protein kinases activation and elevated endoplasmic reticulum stress. Notably, these effects were recapitulated in acinar cells treated with a pharmacological inhibitor of PTP1B. These findings reveal a novel role for pancreatic PTP1B in cerulein- and arginine-induced acute pancreatitis. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  5. Altered Social Behaviours in Neurexin 1α Knockout Mice Resemble Core Symptoms in Neurodevelopmental Disorders

    PubMed Central

    Grayton, Hannah Mary; Missler, Markus

    2013-01-01

    Background Copy number variants have emerged as an important genomic cause of common, complex neurodevelopmental disorders. These usually change copy number of multiple genes, but deletions at 2p16.3, which have been associated with autism, schizophrenia and mental retardation, affect only the neurexin 1 gene, usually the alpha isoform. Previous analyses of neurexin 1α (Nrxn1α) knockout (KO) mouse as a model of these disorders have revealed impairments in synaptic transmission but failed to reveal defects in social behaviour, one of the core symptoms of autism. Methods We performed a detailed investigation of the behavioural effects of Nrxn1α deletion in mice bred onto a pure genetic background (C57BL/6J) to gain a better understanding of its role in neurodevelopmental disorders. Wildtype, heterozygote and homozygote Nrxn1α KO male and female mice were tested in a battery of behavioural tests (n = 9–16 per genotype, per sex). Results In homozygous Nrxn1α KO mice, we observed altered social approach, reduced social investigation, and reduced locomotor activity in novel environments. In addition, male Nrxn1α KO mice demonstrated an increase in aggressive behaviours. Conclusions These are the first experimental data that associate a deletion of Nrxn1α with alterations of social behaviour in mice. Since this represents one of the core symptom domains affected in autism spectrum disorders and schizophrenia in humans, our findings suggest that deletions within NRXN1 found in patients may be responsible for the impairments seen in social behaviours, and that the Nrxn1α KO mice are a useful model of human neurodevelopmental disorder. PMID:23840597

  6. Induced histamine regulates Ni elution from an implanted Ni wire in mice by downregulating neutrophil migration.

    PubMed

    Kishimoto, Yu; Asakawa, Sanki; Sato, Taiki; Takano, Takayuki; Nakajyo, Takahisa; Mizuno, Natsumi; Segawa, Ryosuke; Yoshikawa, Takeo; Hiratsuka, Masahiro; Yanai, Kazuhiko; Ohtsu, Hiroshi; Hirasawa, Noriyasu

    2017-10-01

    Histamine regulates various inflammatory reactions. We have reported that the expression of histidine decarboxylase (HDC) was induced by subcutaneous implantation of nickel (Ni) wire. However, the source and functions of histamine in Ni elution and Ni wire-induced inflammation have not been completely studied. We aimed to elucidate the effects of de novo synthesized histamine on leucocyte infiltration and Ni elution. Implantation of Ni wire induced an increase in the Ni ion content of the surrounding tissues and serum and in the mRNA levels of HDC, a histamine-producing enzyme, macrophage inflammatory protein-2 (MIP-2), a chemoattractant for neutrophils, and monocyte chemoattractant protein-1 (MCP-1), a chemoattractant for monocytes. The Ni wire induced HDC expression even in mast cell-deficient WBB6F1-W/W V mice. In HDC knockout (HDC KO) mice, the Ni wire-induced increase in MIP-2 mRNA expression was significantly higher than that in wild-type mice but not MCP-1. MIP-2 expression was enhanced in histamine H2 receptor knockout (H2R KO) mice but not in WBB6F1-W/W V mice. Histamine inhibited NiCl 2 -induced MIP-2 mRNA expression in mouse bone marrow-derived macrophages (BMDMs) obtained from wild-type mice; this inhibition was not observed in BMDMs from H2R KO mice. Ni elution increased in HDC KO mice, in which leucocyte infiltration also increased, and was suppressed in mice treated with neutrophil-specific antibody. These results suggest that the Ni wire induced HDC expression in non-mast cells and that, in the chronic phase of inflammation, endogenous histamine reduced Ni elution, probably through regulation of MIP-2 expression and neutrophil migration. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Analysis of Košice Meteorite by Mössbauer Spectroscopy

    NASA Astrophysics Data System (ADS)

    Sitek, Jozef; Dekan, Július; Sedlačková, Katarína

    2016-07-01

    The 57Fe Mössbauer spectroscopy method was used to investigate iron-containing compounds in town Košice meteorite fallen on the territory of Slovakia in February 2010. The results showed that the Mössbauer spectra consisted of magnetic and non-magnetic components related to different iron-bearing phases. The non-magnetic phase includes olivine, pyroxene and traces of Fe3+ phase and the magnetic component comprises troilite (FeS) and iron-rich Fe-Ni alloy with hyperfine magnetic field typical for kamacite. Samples from meteorite were obtained in powder from different depths to inspect its heterogeneous composition. The content of kamacite increases to the detriment of troilite from the surface toward the centre of the sample. Measurements at liquid nitrogen temperature confirmed phase composition of investigated meteorite. Main constituent elements of studied samples were also determined by X-ray fluorescence analysis.

  8. Small heterodimer partner (SHP) deficiency protects myocardia from lipid accumulation in high fat diet-fed mice.

    PubMed

    Ohn, Jung Hun; Hwang, Ji Yeon; Moon, Min Kyong; Ahn, Hwa Young; Kim, Hwan Hee; Koo, Young Do; Kim, Kwang-Il; Chang, Hyuk Jae; Lee, Hye Seung; Jang, Hak Chul; Park, Young Joo

    2017-01-01

    The small heterodimer partner (SHP) regulates fatty acid oxidation and lipogenesis in the liver by regulating peroxisome proliferator-activated receptor (PPAR) γ expression. SHP is also abundantly expressed in the myocardium. We investigated the effect of SHP expression on myocardia assessing not only heart structure and function but also lipid metabolism and related gene expression in a SHP deletion animal model. Transcriptional profiling with a microarray revealed that genes participating in cell growth, cytokine signalling, phospholipid metabolism, and extracellular matrix are up-regulated in the myocardia of SHP knockout (KO) mice compared to those of wild-type (WT) mice (nominal p value < 0.05). Consistent with these gene expression changes, the left ventricular masses of SHP KO mice were significantly higher than WT mice (76.8 ± 20.5 mg vs. 52.8 ± 6.8 mg, P = 0.0093). After 12 weeks of high fat diet (HFD), SHP KO mice gained less weight and exhibited less elevation in serum-free fatty acid and less ectopic lipid accumulation in the myocardium than WT mice. According to microarray analysis, genes regulated by PPARγ1 and PPARα were down-regulated in myocardia of SHP KO mice compared to their expression in WT mice after HFD, suggesting that the reduction in lipid accumulation in the myocardium resulted from a decrease in lipogenesis regulated by PPARγ. We confirmed the reduced expression of PPARγ1 and PPARα target genes such as CD36, medium-chain acyl-CoA dehydrogenase, long-chain acyl-CoA dehydrogenase, and very long-chain acyl-CoA dehydrogenase by SHP KO after HFD.

  9. A pathophysiological role of TRPV1 in ischemic injury after transient focal cerebral ischemia in mice

    SciTech Connect

    Miyanohara, Jun; Shirakawa, Hisashi, E-mail: shirakaw@pharm.kyoto-u.ac.jp; Sanpei, Kazuaki

    2015-11-20

    Transient receptor potential vanilloid 1 (TRPV1) is a non-selective cation channel with high Ca{sup 2+} permeability, which functions as a polymodal nociceptor activated by heat, protons and several vanilloids, including capsaicin and anandamide. Although TRPV1 channels are widely distributed in the mammalian brain, their pathophysiological roles in the brain remain to be elucidated. In this study, we investigated whether TRPV1 is involved in cerebral ischemic injury using a middle cerebral artery (MCA) occlusion model in wild-type (WT) and TRPV1-knockout (KO) mice. For transient ischemia, the left MCA of C57BL/6 mice was occluded for 60 min and reperfused at 1 and 2more » days after ischemia. We found that neurological and motor deficits, and infarct volumes in TRPV1-KO mice were lower than those of WT mice. Consistent with these results, intracerebroventricular injection of a TRPV1 antagonist, capsazepine (20 nmol), 30 min before the onset of ischemia attenuated neurological and motor deficits and improved infarct size without influencing cerebral blood flow in the occluded MCA territory. The protective effect of capsazepine on ischemic brain damage was not observed in TRPV1-KO mice. WT and TRPV1-KO mice did not show any differences with respect to the increased number of Iba1-positive microglia/macrophages, GFAP-positive astrocytes, and Gr1-positive neutrophils at 1 and 2 days after cerebral ischemia. Taken together, we conclude that brain TRPV1 channels are activated by ischemic stroke and cause neurological and motor deficits and infarction after brain ischemia. - Highlights: • We investigated whether TRPV1 is involved in transient ischemic brain damage in mice. • Neurological deficits and infarct volumes were lower in TRPV1-KO mice than in WT mice. • Injection of a TRPV1 antagonist, capsazepine, attenuated neurological deficits and improved infarct size. • No differences in astrocytic or microglial activation were observed between WT and TRPV1-KO

  10. Phenotype of capillaries in skeletal muscle of nNOS-knockout mice.

    PubMed

    Baum, Oliver; Vieregge, Max; Koch, Pascale; Gül, Safak; Hahn, Sabine; Huber-Abel, Felicitas A M; Pries, Axel R; Hoppeler, Hans

    2013-06-15

    Because neuronal nitric oxide synthase (nNOS) has a well-known impact on arteriolar blood flow in skeletal muscle, we compared the ultrastructure and the hemodynamics of/in the ensuing capillaries in the extensor digitorum longus (EDL) muscle of male nNOS-knockout (KO) mice and wild-type (WT) littermates. The capillary-to-fiber (C/F) ratio (-9.1%) was lower (P ≤ 0.05) in the nNOS-KO mice than in the WT mice, whereas the mean cross-sectional fiber area (-7.8%) and the capillary density (-3.1%) varied only nonsignificantly (P > 0.05). Morphometrical estimation of the area occupied by the capillaries as well as the volume and surface densities of the subcellular compartments differed nonsignificantly (P > 0.05) between the two strains. Intravital microscopy revealed neither the capillary diameter (+3% in nNOS-KO mice vs. WT mice) nor the mean velocity of red blood cells in EDL muscle (+25% in nNOS-KO mice vs. WT mice) to significantly vary (P > 0.05) between the two strains. The calculated shear stress in the capillaries was likewise nonsignificantly different (3.8 ± 2.2 dyn/cm² in nNOS-KO mice and 2.1 ± 2.2 dyn/cm² in WT mice; P > 0.05). The mRNA levels of vascular endothelial growth factor (VEGF)-A were lower in the EDL muscle of nNOS-KO mice than in the WT littermates (-37%; P ≤ 0.05), whereas mRNA levels of VEGF receptor-2 (VEGFR-2) (-11%), hypoxia inducible factor-1α (+9%), fibroblast growth factor-2 (-14%), and thrombospondin-1 (-10%) differed nonsignificantly (P > 0.05). Our findings support the contention that VEGF-A mRNA expression and C/F-ratio but not the ultrastructure or the hemodynamics of/in capillaries in skeletal muscle at basal conditions depend on the expression of nNOS.

  11. Epac2a-null mice exhibit obesity-prone nature more susceptible to leptin resistance.

    PubMed

    Hwang, M; Go, Y; Park, J-H; Shin, S-K; Song, S E; Oh, B-C; Im, S-S; Hwang, I; Jeon, Y H; Lee, I-K; Seino, S; Song, D-K

    2017-02-01

    The exchange protein directly activated by cAMP (Epac), which is primarily involved in cAMP signaling, has been known to be essential for controlling body energy metabolism. Epac has two isoforms: Epac1 and Epac2. The function of Epac1 on obesity was unveiled using Epac1 knockout (KO) mice. However, the role of Epac2 in obesity remains unclear. To evaluate the role of Epac2 in obesity, we used Epac2a KO mice, which is dominantly expressed in neurons and endocrine tissues. Physiological factors related to obesity were analyzed: body weight, fat mass, food intake, plasma leptin and adiponectin levels, energy expenditure, glucose tolerance, and insulin and leptin resistance. To determine the mechanism of Epac2a, mice received exogenous leptin and then hypothalamic leptin signaling was analyzed. Epac2a KO mice appeared to have normal glucose tolerance and insulin sensitivity until 12 weeks of age, but an early onset increase of plasma leptin levels and decrease of plasma adiponectin levels compared with wild-type mice. Acute leptin injection revealed impaired hypothalamic leptin signaling in KO mice. Consistently, KO mice fed a high-fat diet (HFD) were significantly obese, presenting greater food intake and lower energy expenditure. HFD-fed KO mice were also characterized by greater impairment of hypothalamic leptin signaling and by weaker leptin-induced decrease in food consumption compared with HFD-fed wild-type mice. In wild-type mice, acute exogenous leptin injection or chronic HFD feeding tended to induce hypothalamic Epac2a expression. Considering that HFD is an inducer of hypothalamic leptin resistance and that Epac2a functions in pancreatic beta cells during demands of greater work load, hypothalamic Epac2a may have a role in facilitating leptin signaling, at least in response to higher metabolic demands. Thus, our data indicate that Epac2a is critical for preventing obesity and thus Epac2a activators may be used to manage obesity and obesity-mediated metabolic

  12. Accumulation of cytolytic CD8{sup +} T cells in B16-melanoma and proliferation of mature T cells in TIS21-knockout mice after T cell receptor stimulation

    SciTech Connect

    Ryu, Min Sook; Woo, Min-Yeong; Department of Biomedical Sciences, The Graduate School, Ajou University

    2014-10-01

    In vivo and in vitro effects of TIS21 gene on the mature T cell activation and antitumor activities were explored by employing MO5 melanoma orthograft and splenocytes isolated from the TIS21-knockout (KO) mice. Proliferation and survival of mature T cells were significantly increased in the KO than the wild type (WT) cells, indicating that TIS21 inhibits the rate of mature T cell proliferation and its survival. In MO5 melanoma orthograft model, the KO mice recruited much more CD8{sup +} T cells into the tumors at around day 14 after tumor cell injection along with reduced tumor volumes compared with themore » WT. The increased frequency of granzyme B{sup +} CD8{sup +} T cells in splenocytes of the KO mice compared with the WT may account for antitumor-immunity of TIS21 gene in the melanoma orthograft. In contrast, reduced frequencies of CD107a{sup +} CD8{sup +} T cells in the splenocytes of KO mice may affect the loss of CD8{sup +} T cell infiltration in the orthograft at around day 19. These results indicate that TIS21 exhibits antiproliferative and proapoptotic effects in mature T cells, and differentially affects the frequencies of granzyme B{sup +} CD8{sup +} T-cells and CD107a{sup +} CD8{sup +} T-cells, thus transiently regulating in vivo anti-tumor immunity. - Highlights: • Constitutive expression of TIS21 in splenocytes and upregulation by TCR stimulation. • Proliferation of mature T-cells in spleen of TIS21KO mice after TCR stimulation. • Inhibition of cell death in mature T-cells of TIS21KO mice compared with the wild type. • Inhibition of melanoma growth in TIS21KO mice and CD8{sup +} T cell infiltration in tumor. • Reduction of CD 107{sup +}CD8{sup +} T cells, but increased granzyme B{sup +} CD8{sup +} T cells in TIS21KO mice.« less

  13. Compensatory Changes in Calcium Metabolism Accompany the Loss of Vitamin D Receptor (VDR) from the Distal Intestine and Kidney of Mice

    PubMed Central

    Reyes-Fernandez, Perla C; Fleet, James C

    2016-01-01

    1,25 dihydroxyvitamin D3 (1,25(OH)2D) increases intestinal Ca absorption when dietary Ca intake is low by inducing gene expression through the vitamin D receptor (VDR). 1,25(OH)2D-regulated Ca absorption has been studied extensively in the small intestine, but VDR is also present in the large intestine. Our goal was to determine the impact of large intestinal VDR deletion on Ca and bone metabolism. We used transgenic mice expressing Cre-recombinase driven by the 9.5 kb human caudal type homeobox 2 (CDX2) promoter to delete floxed VDR alleles from the caudal region of the mouse (CDX2-KO). Weanling CDX2-KO mice and control littermates were fed low (0.25%) or normal (0.5%) Ca diets for 7 weeks. Serum and urinary Ca, vitamin D metabolites, bone parameters, and gene expression were analyzed. Loss of the VDR in CDX2-KO was confirmed in colon and kidney. Unexpectedly, CDX2-KO had lower serum PTH (−65% of controls, p<0.001) but normal serum 1,25(OH)2D and Ca levels. Despite elevated urinary Ca loss (8-fold higher in CDX2-KO) and reduced colonic TRPV6 (−90%) and CaBPD9k (−80%) mRNA levels, CDX2-KO mice had only modestly lower femoral bone density. Interestingly, duodenal TRPV6 and CaBPD9k mRNA expression was 4- and 3-fold higher, respectively, and there was a trend towards increased duodenal Ca absorption (+19%, p=0.076) in the CDX2-KO mice. The major finding of this study is that large intestine VDR significantly contributes to whole body Ca metabolism but that duodenal compensation may prevent the consequences of VDR deletion from large intestine and kidney in growing mice. PMID:26211511

  14. Compensatory Changes in Calcium Metabolism Accompany the Loss of Vitamin D Receptor (VDR) From the Distal Intestine and Kidney of Mice.

    PubMed

    Reyes-Fernandez, Perla C; Fleet, James C

    2016-01-01

    1,25 Dihydroxyvitamin D3 (1,25(OH)2 D) increases intestinal Ca absorption when dietary Ca intake is low by inducing gene expression through the vitamin D receptor (VDR). 1,25(OH)2 D-regulated Ca absorption has been studied extensively in the small intestine, but VDR is also present in the large intestine. Our goal was to determine the impact of large intestinal VDR deletion on Ca and bone metabolism. We used transgenic mice expressing Cre-recombinase driven by the 9.5-kb human caudal type homeobox 2 (CDX2) promoter to delete floxed VDR alleles from the caudal region of the mouse (CDX2-KO). Weanling CDX2-KO mice and control littermates were fed low (0.25%) or normal (0.5%) Ca diets for 7 weeks. Serum and urinary Ca, vitamin D metabolites, bone parameters, and gene expression were analyzed. Loss of the VDR in CDX2-KO was confirmed in colon and kidney. Unexpectedly, CDX2-KO had lower serum PTH (-65% of controls, p < 0.001) but normal serum 1,25(OH)2 D and Ca levels. Despite elevated urinary Ca loss (eightfold higher in CDX2-KO) and reduced colonic target genes TRPV6 (-90%) and CaBPD9k (-80%) mRNA levels, CDX2-KO mice had only modestly lower femoral bone density. Interestingly, duodenal TRPV6 and CaBPD9k mRNA expression was fourfold and threefold higher, respectively, and there was a trend toward increased duodenal Ca absorption (+19%, p = 0.076) in the CDX2-KO mice. The major finding of this study is that large intestine VDR significantly contributes to whole-body Ca metabolism but that duodenal compensation may prevent the consequences of VDR deletion from large intestine and kidney in growing mice. © 2015 American Society for Bone and Mineral Research.

  15. Regional brain uptake of the muscarinic ligand, [18F]FP-TZTP, is greatly decreased in M2 receptor knockout mice but not in M1, M3 and M4 receptor knockout mice.

    PubMed

    Jagoda, E M; Kiesewetter, D O; Shimoji, K; Ravasi, L; Yamada, M; Gomeza, J; Wess, J; Eckelman, W C

    2003-04-01

    A muscarinic receptor radioligand, 3-(3-(3-fluoropropyl)thio) -1,2,5,thiadiazol-4-yl)-1,2,5,6-tetrahydro-1-methylpyridine (fP-TZTP) radiolabeled with the positron emitting radionuclide (18)F ([(18)F]FP-TZTP) displayed regional brain distribution consistent with M2 receptor densities in rat brain. The purpose of the present study is to further elucidate the subtype selectivity of [(18)F]FP-TZTP using genetically engineered mice which lacked functional M1, M2, M3, or M4 muscarinic receptors. Using ex vivo autoradiography, the regional brain localization of [(18)F]FP-TZTP in M2 knockout (M2 KO) was significantly decreased (51.3 to 61.4%; P<0.01) when compared to the wild-type (WT) mice in amygdala, brain stem, caudate putamen, cerebellum, cortex, hippocampus, hypothalamus, superior colliculus, and thalamus. In similar studies with M1KO, M3KO and M4KO compared to their WT mice, [(18)F]FP-TZTP uptakes in the same brain regions were not significantly decreased at P<0.01. However, in amygdala and hippocampus small decreases of 19.5% and 22.7%, respectively, were observed for M1KO vs WT mice at P<0.05. Given the fact that large decreases in [(18)F]FP-TZTP brain uptakes were seen only in M2 KO vs. WT mice, we conclude that [(18)F]FP-TZTP preferentially labels M2 receptors in vivo.

  16. FGF 21 deficiency slows gastric emptying and reduces initial blood alcohol concentration in mice exposed to acute alcohol in fasting state.

    PubMed

    Wu, Guicheng; Liu, Yanlong; Liu, Yunhuan; Zhang, Lihua; Zhao, Haiyang; Liu, Liming; Zhao, Cuiqing; Feng, Wenke

    2018-02-26

    Excess alcohol consumption can lead to alcoholic liver disease. Fibroblast growth factor 21 (FGF21) is a metabolic regulator with multiple physiologic functions. Previous study demonstrated that FGF21 deficiency exacerbated alcohol-induced liver injury and exogenous FGF21 administration protected liver from chronic alcohol-induced injury. In this study, we aimed to explore the role of FGF21 in alcohol metabolism in mice. FGF21 knockout (KO) mice and the wild type(WT) control mice were divided into two groups and fasted for 24 h followed by a bonus of alcohol treatment at a dose of 5 g/kg body weight via gavage. Serum alcohol concentration was measured after gavage at 0.5, 2, 3, 4 and 6 h, respectively. At the end, gastric and liver tissues were collected. Serum alcohol concentration of KO mice was significantly lower than that of WT at 0.5 h after alcohol expose. There were no significant differences in alcohol dehydrogenase (ADH) activity and aldehyde dehydrogenase 2 (ALDH2) activity in gastric and liver tissues between WT and the KO mice. However, gastric emptying time of KO mice was much longer than that of WT mice. In addition, the intestinal permeability and serum GLP-1 level of KO mice were significantly higher than that of WT mice. These results suggest that FGF21 deficiency slow gastric emptying rate and indirectly influence initial alcohol metabolism in mice exposed to acute alcohol. Our findings provide additional information for understanding the gastrointestinal mechanism of alcoholic liver disease and other alcohol use disorders. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Adrenal-specific scavenger receptor BI deficiency induces glucocorticoid insufficiency and lowers plasma very-low-density and low-density lipoprotein levels in mice.

    PubMed

    Hoekstra, Menno; van der Sluis, Ronald J; Van Eck, Miranda; Van Berkel, Theo J C

    2013-02-01

    We determined the physiological consequences of adrenocortical-specific deletion of scavenger receptor BI (SR-BI) function in C57BL/6 wild-type mice. One adrenal from 10-day-old SR-BI knockout (KO) mice or wild-type controls was transplanted under the renal capsule of adrenalectomized C57BL/6 recipient mice. The fasting plasma corticosterone level increased over time in transplanted mice. Corticosterone values in SR-BI KO transplanted mice remained ≈50% lower (P<0.001) as compared with wild-type transplanted mice, which coincided with adrenocortical lipid depletion. A 6.5-fold higher (P<0.01) plasma adrenocorticotropic hormone level was present in SR-BI KO transplanted mice reminiscent of primary glucocorticoid insufficiency. On feeding with cholic acid-containing high cholesterol/high fat diet, SR-BI KO transplanted mice exhibited a 26% (P<0.05) reduction in their liver triglyceride level. Hepatic myosin regulatory light chain interacting protein/inducible degrader of the low-density lipoprotein receptor mRNA expression was 48% (P<0.01) decreased in adrenal-specific SR-BI KO mice, which was paralleled by a marked decrease (-46%; P<0.01) in proatherogenic very-low-density and low-density lipoprotein levels. Adrenal-specific disruption of SR-BI function induces glucocorticoid insufficiency and lowers plasma very-low-density and low-density lipoprotein levels in atherogenic diet-fed C57BL/6 mice. These findings further highlight the interaction between adrenal high-density lipoprotein-cholesterol uptake by SR-BI, adrenal steroidogenesis, and the regulation of hepatic lipid metabolism.

  18. Absence of the glucagon-like peptide-1 receptor does not affect the metabolic phenotype of mice with liver-specific G(s)α deficiency.

    PubMed

    Chen, Min; Mema, Eralda; Kelleher, James; Nemechek, Nicholas; Berger, Alta; Wang, Jie; Xie, Tao; Gavrilova, Oksana; Drucker, Daniel J; Weinstein, Lee S

    2011-09-01

    The stimulatory G protein α-subunit (G(s)α) couples hormone and other receptors to the generation of intracellular cAMP. We previously showed that mice with liver-specific G(s)α deficiency [liver-specific G(s)α knockout (LGsKO) mice] had reduced adiposity and improved glucose tolerance associated with increased glucose-stimulated insulin secretion, pancreatic islet hyperplasia, and very high serum glucagon and glucagon-like peptide 1 (GLP-1) levels. Because GLP-1 is known to stimulate insulin secretion and to have effects on energy balance, we mated LGsKO mice with germline GLP-1 receptor (GLP-1R) knockout mice (Glp1r(-/-)) and compared LGsKO to double-knockout (LGs/Glp1r(-/-)) mice to determine the contribution of excess GLP-1R signaling to the LGsKO phenotype. Loss of the GLP-1R failed to reverse most of the metabolic features of LGsKO mice, including reduced fat mass, increased glucose tolerance, and second-phase glucose-stimulated insulin secretion, islet cell hyperplasia, and very high glucagon and GLP-1 levels. However, loss of GLP-1R impaired first-phase insulin secretion in mice with or without liver-specific G(s)α deficiency. Thus, excess GLP-1 action (or at least through GLP-1R) does not contribute to the LGsKO metabolic phenotype, and other unknown factors involved in the cross talk between the liver G(s)α/cAMP pathway and pancreatic islet function need to be further elucidated.

  19. Assessing Interactions Between Ghsr and Mc3r Reveals a Role for AgRP in the Expression of Food Anticipatory Activity in Male Mice

    PubMed Central

    Girardet, Clemence; Mavrikaki, Maria; Southern, Mark R.; Smith, Roy G.

    2014-01-01

    The stomach hormone ghrelin and hypothalamic melanocortin neurons belong to a gut-brain circuit controlling appetite and metabolic homeostasis. Mice lacking melanocortin-3 receptor (Mc3rKO) or growth hormone secretagogue receptor (GhsrKO) genes exhibit attenuated food anticipatory activity (FAA), a rise in locomotor activity anticipating mealtime, suggesting common circuitry regulating anticipatory responses to nutrient loading. To investigate the interaction between Ghsrs and Mc3rs, we compared food anticipatory responses in GhsrKO, Mc3rKO, and double Ghsr;Mc3r knockout (DKO) mice subjected to a hypocaloric restricted feeding (RF) protocol in constant dark or 12-hour light, 12-hour dark settings. DKO are viable, exhibiting no overt behavioral or metabolic phenotypes in ad libitum or fasting conditions. FAA was initially attenuated in all mutant strains in constant darkness. However, GhsrKO eventually exhibited a robust food anticipatory response, suggesting compensation. Mc3rKO and DKO did not compensate, indicating a continued requirement for Mc3rs in maintaining the expression of FAA in situations of RF. Abnormal regulation of hypothalamic agouti-related peptide/neuropeptide Y (AgRP/Npy) neurons previously observed during fasting may contribute to attenuated FAA in Mc3rKO. AgRP and Npy expression measured 1 hour before food presentation correlated positively with FAA. Absence of Mc3rs (but not Ghsrs) was associated with lower AgRP/Npy expression, suggesting attenuated responses to signals of negative energy balance. These observations support the importance of Mc3rs as modulators of anticipatory responses to feeding, with mice able to compensate for loss of Ghsrs. The behavioral deficits of Mc3rKO displayed during RF may be partially explained by reduced hunger sensations owing to abnormal regulation of orexigenic AgRP/Npy neurons. PMID:25211592

  20. Expression of neuronal nitric oxide synthase splice variants in atherosclerotic plaques of apoE knockout mice

    PubMed Central

    Schödel, Johannes; Padmapriya, P.; Marx, Alexander; Huang, Paul L.; Ertl, Georg; Kuhlencordt, Peter J.

    2009-01-01

    Objective We previously reported that deletion of brain type neuronal nitric oxide synthase-α (nNOS-α) accelerates atherosclerosis in apolipoproteinE (apoE) knockout (ko) mice. The regulation of nNOS expression is complex, involving the generation of mRNA splice variants. The current study investigates occurrence and distribution of nNOS variants in atherosclerotic lesions of apoE ko and apoE/nNOS-α double ko (dko) animals. Methods Mice were fed a high fat diet for 20 weeks. Immunohistochemistry and Western blot analysis were performed using antibodies detecting the carboxy terminal-, or amino terminal-residue of the nNOS protein. Confocal microscopy and in situ hybridization were used to identify the compartment of cellular expression. Results In situ hybridization revealed the presence of nNOS-α and -γ mRNA variants in apoE ko plaques, while only nNOS-γ was detectable in apoE/nNOS dko plaques. Consistent with mRNA expression nNOS-α protein can be detected in the neointima of apoE ko, but not apoE/nNOS dko animals. In contrast, the carboxy terminal antibody stained the neointima and media in apoE ko vessels and showed residual nNOS immunoreactivity in apoE/nNOS dko lesions. Confocal microscopy showed predominant nNOS expression in vascular smooth muscle cells, while colocalization with macrophages was less pronounced. Conclusions Our study shows that nNOS-α and -γ splice variants are expressed in atherosclerotic plaques of apoE ko mice. nNOS variants colocalized with markers for vascular smooth muscle cells and macrophages but not for endothelial cells. Since nNOS-α is atheroprotective, other nNOS splice variants which differ in enzyme kinetic and subcellular localization may also influence plaque formation. PMID:19358992

  1. Expression of neuronal nitric oxide synthase splice variants in atherosclerotic plaques of apoE knockout mice.

    PubMed

    Schödel, Johannes; Padmapriya, P; Marx, Alexander; Huang, Paul L; Ertl, Georg; Kuhlencordt, Peter J

    2009-10-01

    We previously reported that deletion of brain type neuronal nitric oxide synthase-alpha (nNOS-alpha) accelerates atherosclerosis in apolipoproteinE (apoE) knockout (ko) mice. The regulation of nNOS expression is complex, involving the generation of mRNA splice variants. The current study investigates occurrence and distribution of nNOS variants in atherosclerotic lesions of apoE ko and apoE/nNOS-alpha double ko (dko) animals. Mice were fed a high fat diet for 20 weeks. Immunohistochemistry and western blot analysis were performed using antibodies detecting the carboxy terminal-, or amino terminal-residue of the nNOS protein. Confocal microscopy and in situ hybridization were used to identify the compartment of cellular expression. In situ hybridization revealed the presence of nNOS-alpha and -gamma mRNA variants in apoE ko plaques, while only nNOS-gamma was detectable in apoE/nNOS dko plaques. Consistent with mRNA expression nNOS-alpha protein can be detected in the neointima of apoE ko, but not apoE/nNOS dko animals. In contrast, the carboxy terminal antibody stained the neointima and media in apoE ko vessels and showed residual nNOS immunoreactivity in apoE/nNOS dko lesions. Confocal microscopy showed predominant nNOS expression in vascular smooth muscle cells, while colocalization with macrophages was less pronounced. Our study shows that nNOS-alpha and -gamma splice variants are expressed in atherosclerotic plaques of apoE ko mice. nNOS variants colocalized with markers for vascular smooth muscle cells and macrophages but not for endothelial cells. Since nNOS-alpha is atheroprotective, other nNOS splice variants which differ in enzyme kinetic and subcellular localization may also influence plaque formation.

  2. Zfp462 deficiency causes anxiety-like behaviors with excessive self-grooming in mice.

    PubMed

    Wang, B; Zheng, Y; Shi, H; Du, X; Zhang, Y; Wei, B; Luo, M; Wang, H; Wu, X; Hua, X; Sun, M; Xu, X

    2017-02-01

    Zfp462 is a newly identified vertebrate-specific zinc finger protein that contains nearly 2500 amino acids and 23 putative C2H2-type zinc finger domains. So far, the functions of Zfp462 remain unclear. In our study, we showed that Zfp462 is expressed predominantly in the developing brain, especially in the cerebral cortex and hippocampus regions from embryonic day 7.5 to early postnatal stage. By using a piggyBac transposon-generated Zfp462 knockout (KO) mouse model, we found that Zfp462 KO mice exhibited prenatal lethality with normal neural tube patterning, whereas heterozygous (Het) Zfp462 KO (Zfp462 +/- ) mice showed developmental delay with low body weight and brain weight. Behavioral studies showed that Zfp462 +/- mice presented anxiety-like behaviors with excessive self-grooming and hair loss, which were similar to the pathological grooming behaviors in Hoxb8 KO mice. Further analysis of grooming microstructure showed the impairment of grooming patterning in Zfp462 +/- mice. In addition, the mRNA levels of Pbx1 (pre-B-cell leukemia homeobox 1, an interacting protein of Zfp462) and Hoxb8 decreased in the brains of Zfp462 +/- mice, which may be the cause of anxiety-like behaviors. Finally, imipramine, a widely used and effective anti-anxiety medicine, rescued anxiety-like behaviors and excessive self-grooming in Zfp462 +/- mice. In conclusion, Zfp462 deficiency causes anxiety-like behaviors with excessive self-grooming in mice. This provides a novel genetic mouse model for anxiety disorders and a useful tool to determine potential therapeutic targets for anxiety disorders and screen anti-anxiety drugs. © 2016 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  3. Disruption of Nrf2 exacerbated the damage after spinal cord injury in mice.

    PubMed

    Mao, Lei; Wang, Han-Dong; Wang, Xiao-Liang; Tian, Lei; Xu, Jian-Ya

    2012-01-01

    Nuclear factor erythroid 2-related factor 2 (Nrf2) is a key transcriptional factor for antioxidant response element-regulated genes. After spinal cord injury (SCI), the Nrf2-antioxidant response element pathway is activated in the spinal cord. However, the function of Nrf2 after SCI has not yet been studied. Spinal cord compression injury of Nrf2 knockout (KO) and wild-type (WT) mice was induced by the application of vascular clips (force of 10 g) to the dura. Neurologic function was assayed by the Basso open-field motor score, footprint analysis, and spinal motor-evoked potentials. Degenerating neuronal cells were stained with Fluoro Jade C and observed by a confocal microscopy. Nrf2 DNA-binding activity was assessed by electrophoretic mobility shift assay. The mRNA levels of interleukin (IL)-6, IL-1β, NAD(P)H: quinone oxidoreductase (NQO)-1, and glutathione S-transferase (GST)-α1 were detected by reverse transcriptase-polymerase chain reaction. Enzyme-linked immunosorbent assay was used to detect IL-6 and IL-1β protein expression, and colorimetric method was used to detect the enzyme activity of NQO1 and GST-α1. Nrf2 KO mice developed severer hindlimb motor dysfunction and neuronal death after SCI compared with WT mice. In correlation with neurologic deficits, the release of IL-6 and IL-1β in the spinal cord of KO mice was higher than that in WT mice, whereas the Nrf2 banding activity, the expression and activity of NQO1 and GST-α1 were all lesser in KO mice 24 hours after SCI compared with WT mice. Genetic ablation of Nrf2 exacerbated the neurologic deficit and inflammation after SCI in mice. These findings raise the possibility that Nrf2 could be relevant in improving outcome after SCI.

  4. High-density lipoprotein maintains skeletal muscle function by modulating cellular respiration in mice.

    PubMed

    Lehti, Maarit; Donelan, Elizabeth; Abplanalp, William; Al-Massadi, Omar; Habegger, Kirk M; Weber, Jon; Ress, Chandler; Mansfeld, Johannes; Somvanshi, Sonal; Trivedi, Chitrang; Keuper, Michaela; Ograjsek, Teja; Striese, Cynthia; Cucuruz, Sebastian; Pfluger, Paul T; Krishna, Radhakrishna; Gordon, Scott M; Silva, R A Gangani D; Luquet, Serge; Castel, Julien; Martinez, Sarah; D'Alessio, David; Davidson, W Sean; Hofmann, Susanna M

    2013-11-26

    Abnormal glucose metabolism is a central feature of disorders with increased rates of cardiovascular disease. Low levels of high-density lipoprotein (HDL) are a key predictor for cardiovascular disease. We used genetic mouse models with increased HDL levels (apolipoprotein A-I transgenic [apoA-I tg]) and reduced HDL levels (apoA-I-deficient [apoA-I ko]) to investigate whether HDL modulates mitochondrial bioenergetics in skeletal muscle. ApoA-I ko mice exhibited fasting hyperglycemia and impaired glucose tolerance test compared with wild-type mice. Mitochondria isolated from gastrocnemius muscle of apoA-I ko mice displayed markedly blunted ATP synthesis. Endurance capacity during exercise exhaustion test was impaired in apoA-I ko mice. HDL directly enhanced glucose oxidation by increasing glycolysis and mitochondrial respiration rate in C2C12 muscle cells. ApoA-I tg mice exhibited lower fasting glucose levels, improved glucose tolerance test, increased lactate levels, reduced fat mass, associated with protection against age-induced decline of endurance capacity compared with wild-type mice. Circulating levels of fibroblast growth factor 21, a novel biomarker for mitochondrial respiratory chain deficiencies and inhibitor of white adipose lipolysis, were significantly reduced in apoA-I tg mice. Consistent with an increase in glucose utilization of skeletal muscle, genetically increased HDL and apoA-I levels in mice prevented high-fat diet-induced impairment of glucose homeostasis. In view of impaired mitochondrial function and decreased HDL levels in type 2 diabetes mellitus, our findings indicate that HDL-raising therapies may preserve muscle mitochondrial function and address key aspects of type 2 diabetes mellitus beyond cardiovascular disease.

  5. Mice deficient in PAPP-A show resistance to the development of diabetic nephropathy.

    PubMed

    Mader, Jessica R; Resch, Zachary T; McLean, Gary R; Mikkelsen, Jakob H; Oxvig, Claus; Marler, Ronald J; Conover, Cheryl A

    2013-10-01

    We investigated pregnancy-associated plasma protein-A (PAPP-A) in diabetic nephropathy. Normal human kidney showed specific staining for PAPP-A in glomeruli, and this staining was markedly increased in diabetic kidney. To assess the possible contribution of PAPP-A in the development of diabetic nephropathy, we induced diabetes with streptozotocin in 14-month-old WT and Papp-A knockout (KO) mice. Renal histopathology was evaluated after 4 months of stable hyperglycemia. Kidneys from diabetic WT mice showed multiple abnormalities including thickening of Bowman's capsule (100% of mice), increased glomerular size (80% of mice), tubule dilation (80% of mice), and mononuclear cell infiltration (90% of mice). Kidneys of age-matched non-diabetic WT mice had similar evidence of tubule dilation and mononuclear cell infiltration to those of diabetic WT mice, indicating that these changes were predominantly age-related. However, thickened Bowman's capsule and increased glomerular size appeared specific for the experimental diabetes. Kidneys from diabetic Papp-A KO mice had significantly reduced or no evidence of changes in Bowman's capsule thickening and glomerular size. There was also a shift to larger mesangial area and increased macrophage staining in diabetic WT mice compared with Papp-A KO mice. In summary, elevated PAPP-A expression in glomeruli is associated with diabetic nephropathy in humans and absence of PAPP-A is associated with resistance to the development of indicators of diabetic nephropathy in mice. These data suggest PAPP-A as a potential therapeutic target for diabetic nephropathy.

  6. Editor’s Highlight: Complete Attenuation of Mouse Lung Cell Proliferation and Tumorigenicity in CYP2F2 Knockout and CYP2F1 Humanized Mice Exposed to Inhaled Styrene for up to 2 Years Supports a Lack of Human Relevance

    PubMed Central

    Cruzan, George; Bus, James S.; Banton, Marcy I.; Sarang, Satinder S.; Waites, Robbie; Layko, Debra B.; Raymond, James; Dodd, Darol; Andersen, Melvin E.

    2017-01-01

    Abstract Styrene is a mouse-specific lung carcinogen, and short-term mode of action studies have demonstrated that cytotoxicity and/or cell proliferation, and genomic changes are dependent on CYP2F2 metabolism. The current study examined histopathology, cell proliferation, and genomic changes in CD-1, C57BL/6 (WT), CYP2F2(−/−) (KO), and CYP2F2(−/−) (CYP2F1, 2B6, 2A13-transgene) (TG; humanized) mice following exposure for up to 104 weeks to 0- or 120-ppm styrene vapor. Five mice per treatment group were sacrificed at 1, 26, 52, and 78 weeks. Additional 50 mice per treatment group were followed until death or 104 weeks of exposure. Cytotoxicity was present in the terminal bronchioles of some CD-1 and WT mice exposed to styrene, but not in KO or TG mice. Hyperplasia in the terminal bronchioles was present in CD-1 and WT mice exposed to styrene, but not in KO or TG mice. Increased cell proliferation, measured by KI-67 staining, occurred in CD-1 and WT mice exposed to styrene for 1 week, but not after 26, 52, or 78 weeks, nor in KO or TG mice. Styrene increased the incidence of bronchioloalveolar adenomas and carcinomas in CD-1 mice. No increase in lung tumors was found in WT despite clear evidence of lung toxicity, or, KO or TG mice. The absence of preneoplastic lesions and tumorigenicity in KO and TG mice indicates that mouse-specific CYP2F2 metabolism is responsible for both the short-term and chronic toxicity and tumorigenicity of styrene, and activation of styrene by CYP2F2 is a rodent MOA that is neither quantitatively or qualitatively relevant to humans. PMID:28962520

  7. Acetaminophen-induced liver damage in mice is associated with gender-specific adduction of peroxiredoxin-6.

    PubMed

    Mohar, Isaac; Stamper, Brendan D; Rademacher, Peter M; White, Collin C; Nelson, Sidney D; Kavanagh, Terrance J

    2014-01-01

    The mechanism by which acetaminophen (APAP) causes liver damage evokes many aspects drug metabolism, oxidative chemistry, and genetic-predisposition. In this study, we leverage the relative resistance of female C57BL/6 mice to APAP-induced liver damage (AILD) compared to male C57BL/6 mice in order to identify the cause(s) of sensitivity. Furthermore, we use mice that are either heterozygous (HZ) or null (KO) for glutamate cysteine ligase modifier subunit (Gclm), in order to titrate the toxicity relative to wild-type (WT) mice. Gclm is important for efficient de novo synthesis of glutathione (GSH). APAP (300 mg/kg, ip) or saline was administered and mice were collected at 0, 0.5, 1, 2, 6, 12, and 24 h. Male mice showed marked elevation in serum alanine aminotransferase by 6 h. In contrast, female WT and HZ mice showed minimal toxicity at all time points. Female KO mice, however, showed AILD comparable to male mice. Genotype-matched male and female mice showed comparable APAP-protein adducts, with Gclm KO mice sustaining significantly greater adducts. ATP was depleted in mice showing toxicity, suggesting impaired mitochondria function. Indeed, peroxiredoxin-6, a GSH-dependent peroxiredoxin, was preferentially adducted by APAP in mitochondria of male mice but rarely adducted in female mice. These results support parallel mechanisms of toxicity where APAP adduction of peroxiredoxin-6 and sustained GSH depletion results in the collapse of mitochondria function and hepatocyte death. We conclude that adduction of peroxiredoxin-6 sensitizes male C57BL/6 mice to toxicity by acetaminophen.

  8. KoVariome: Korean National Standard Reference Variome database of whole genomes with comprehensive SNV, indel, CNV, and SV analyses.

    PubMed

    Kim, Jungeun; Weber, Jessica A; Jho, Sungwoong; Jang, Jinho; Jun, JeHoon; Cho, Yun Sung; Kim, Hak-Min; Kim, Hyunho; Kim, Yumi; Chung, OkSung; Kim, Chang Geun; Lee, HyeJin; Kim, Byung Chul; Han, Kyudong; Koh, InSong; Chae, Kyun Shik; Lee, Semin; Edwards, Jeremy S; Bhak, Jong

    2018-04-04

    High-coverage whole-genome sequencing data of a single ethnicity can provide a useful catalogue of population-specific genetic variations, and provides a critical resource that can be used to more accurately identify pathogenic genetic variants. We report a comprehensive analysis of the Korean population, and present the Korean National Standard Reference Variome (KoVariome). As a part of the Korean Personal Genome Project (KPGP), we constructed the KoVariome database using 5.5 terabases of whole genome sequence data from 50 healthy Korean individuals in order to characterize the benign ethnicity-relevant genetic variation present in the Korean population. In total, KoVariome includes 12.7M single-nucleotide variants (SNVs), 1.7M short insertions and deletions (indels), 4K structural variations (SVs), and 3.6K copy number variations (CNVs). Among them, 2.4M (19%) SNVs and 0.4M (24%) indels were identified as novel. We also discovered selective enrichment of 3.8M SNVs and 0.5M indels in Korean individuals, which were used to filter out 1,271 coding-SNVs not originally removed from the 1,000 Genomes Project when prioritizing disease-causing variants. KoVariome health records were used to identify novel disease-causing variants in the Korean population, demonstrating the value of high-quality ethnic variation databases for the accurate interpretation of individual genomes and the precise characterization of genetic variations.

  9. Near-Complete Genome Sequence of Thalassospira sp. Strain KO164 Isolated from a Lignin-Enriched Marine Sediment Microcosm

    DOE PAGES

    Woo, Hannah L.; O’Dell, Kaela B.; Utturkar, Sagar; ...

    2016-11-23

    We isolated Thalassospirasp. strain KO164 from eastern Mediterranean seawater and sediment laboratory microcosms enriched on insoluble organosolv lignin under oxic conditions. Furthermore, an analysis of the deep-ocean bacterium’s ability to degrade recalcitrant organics such as lignin near-complete genome sequence, will be presented here.

  10. Methods for In-Flight Wing Shape Predictions of Highly Flexible Unmanned Aerial Vehicles: Formulation of Ko Displacement Theory

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Fleischer, Van Tran

    2010-01-01

    The Ko displacement theory is formulated for a cantilever tubular wing spar under bending, torsion, and combined bending and torsion loading. The Ko displacement equations are expressed in terms of strains measured at multiple sensing stations equally spaced on the surface of the wing spar. The bending and distortion strain data can then be input to the displacement equations to calculate slopes, deflections, and cross-sectional twist angles of the wing spar at the strain-sensing stations for generating the deformed shapes of flexible aircraft wing spars. The displacement equations have been successfully validated for accuracy by finite-element analysis. The Ko displacement theory that has been formulated could also be applied to calculate the deformed shape of simple and tapered beams, plates, and tapered cantilever wing boxes. The Ko displacement theory and associated strain-sensing system (such as fiber optic sensors) form a powerful tool for in-flight deformation monitoring of flexible wings and tails, such as those often employed on unmanned aerial vehicles. Ultimately, the calculated displacement data can be visually displayed in real time to the ground-based pilot for monitoring the deformed shape of unmanned aerial vehicles during flight.

  11. Key on demand (KoD) for software-defined optical networks secured by quantum key distribution (QKD).

    PubMed

    Cao, Yuan; Zhao, Yongli; Colman-Meixner, Carlos; Yu, Xiaosong; Zhang, Jie

    2017-10-30

    Software-defined optical networking (SDON) will become the next generation optical network architecture. However, the optical layer and control layer of SDON are vulnerable to cyberattacks. While, data encryption is an effective method to minimize the negative effects of cyberattacks, secure key interchange is its major challenge which can be addressed by the quantum key distribution (QKD) technique. Hence, in this paper we discuss the integration of QKD with WDM optical networks to secure the SDON architecture by introducing a novel key on demand (KoD) scheme which is enabled by a novel routing, wavelength and key assignment (RWKA) algorithm. The QKD over SDON with KoD model follows two steps to provide security: i) quantum key pools (QKPs) construction for securing the control channels (CChs) and data channels (DChs); ii) the KoD scheme uses RWKA algorithm to allocate and update secret keys for different security requirements. To test our model, we define a security probability index which measures the security gain in CChs and DChs. Simulation results indicate that the security performance of CChs and DChs can be enhanced by provisioning sufficient secret keys in QKPs and performing key-updating considering potential cyberattacks. Also, KoD is beneficial to achieve a positive balance between security requirements and key resource usage.

  12. Acquisition of the Korean Imperfective Aspect Markers "-ko iss-" and "-a iss-" by Japanese Learners: A Multiple-Factor Account

    ERIC Educational Resources Information Center

    Ryu, Ju-Yeon; Horie, Kaoru; Shirai, Yasuhiro

    2015-01-01

    Although cross-linguistic research on second language tense-aspect acquisition has uncovered universal tendencies concerning the association between verbal semantics and tense-aspect markers, it is still unclear what mechanisms underlie this link. This study investigates the acquisition of two imperfective aspect markers ("-ko iss-" and…

  13. Altered lipid partitioning and glucocorticoid availability in CBG-deficient male mice with diet-induced obesity.

    PubMed

    Gulfo, José; Ledda, Angelo; Serra, Elisabet; Cabot, Cristina; Esteve, Montserrat; Grasa, Mar

    2016-08-01

    To evaluate how deficiency in corticosteroid-binding globulin (CBG), the specific carrier of glucocorticoids, affects glucocorticoid availability and adipose tissue in obesity. C57BL/6 (WT) and CBG-deficient (KO) male mice were fed during 12 weeks with standard or hyperlipidic diet (HL). Glucocorticoid availability and metabolic parameters were assessed. Body weight and food intake were increased in KO compared with WT mice fed a standard diet and were similar when fed a HL diet. Expression of CBG was found in white adipose tissue by immunochemistry, real-time PCR, and Western blot. In obesity, the subcutaneous depot developed less in KO mice compared with WT, which was associated with a minor adipocyte area and peroxisome proliferator-activated receptor-γ expression. Conversely, the epididymal depot displayed higher weight and adipocyte area in KO than in WT mice. CBG deficiency caused a fall of hepatic 11β-hydroxysteroid dehydrogenase type 2 expression and an increase in epidymal adipose tissue, particularly in HL mice. Deficiency in CBG drives lipid partitioning from subcutaneous to visceral adipose depot under a context of lipid excess and differentially modulates 11β-hydroxysteroid dehydrogenase type 2 expression. © 2016 The Obesity Society.

  14. Behavioral phenotyping of calcium channel (CACN) subunit α2δ3 knockout mice: Consequences of sensory cross-modal activation.

    PubMed

    Landmann, Julia; Richter, Franziska; Classen, Joseph; Richter, Angelika; Penninger, Josef M; Bechmann, Ingo

    2018-01-02

    Sensory cross-activation is still ill-defined and research concerning the consequences of sensory mergence on normal brain function is very limited. Human studies describe behavioral benefits of people with synesthesia- a peculiar form of perception possibly due to cross-modal activation- regarding sensory and memory abilities. Here, we studied behavioral alterations in calcium channel (CACN) subunit α2δ3 knockout (KO) mice exhibiting pain-induced cortical cross-modal activation. Knockout mice exhibited an increased response upon touch of a pinna and impaired audition, while elementary olfaction, vision, somatosensation and motor function were not altered. In contrast to synesthetic humans for whom enhanced memory function had been described, α2δ3 KO mice might have developed defects for object-based memory. However, in a task requiring use of multiple modalities, mutant mice revealed an enhanced performance compared to wild-type controls. Furthermore, several tests revealed evidence for increased anxiety-like behavior of α2δ3 KO animals. In summary, deficits in single sensory abilities and a potential gain in processing simultaneous sensory information in α2δ3 KO mice might represent behavioral correlates of sensory cross-activation. Further, our data suggest a role of CACNα2δ3 within the functionality of the sensory system, but not the motor system and general health. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Reduced cortical BDNF expression and aberrant memory in Carf knockout mice

    PubMed Central

    McDowell, Kelli A.; Hutchinson, Ashley N.; Wong-Goodrich, Sarah J.E.; Presby, Matthew M.; Su, Dan; Rodriguiz, Ramona M.; Law, Krystal C.; Williams, Christina L.; Wetsel, William C.; West, Anne E.

    2010-01-01

    Transcription factors are a key point of convergence between the cell-intrinsic and extracellular signals that guide synaptic development and brain plasticity. Calcium-Response Factor (CaRF) is a unique transcription factor first identified as a binding protein for a calcium-response element in the gene encoding Brain-Derived Neurotrophic Factor (Bdnf). We have now generated Carf knockout (KO) mice to characterize the function of this factor in vivo. Intriguingly, Carf KO mice have selectively reduced expression of Bdnf exon IV-containing mRNA transcripts and BDNF protein in the cerebral cortex while BDNF levels in the hippocampus and striatum remain unchanged, implicating CaRF as a brain region-selective regulator of BDNF expression. At the cellular level, Carf KO mice show altered expression of GABAergic proteins at striatal synapses, raising the possibility that CaRF may contribute to aspects of inhibitory synapse development. Carf KO mice show normal spatial learning in the Morris water maze and normal context-dependent fear conditioning. However they have an enhanced ability to find a new platform location on the first day of reversal training in the water maze and they extinguish conditioned fear more slowly than their wildtype (WT) littermates. Finally, Carf KO mice show normal short-term and long-term memory in a novel object recognition task, but exhibit impairments during the remote memory phase of testing. Taken together these data reveal novel roles for CaRF in the organization and/or function of neural circuits that underlie essential aspects of learning and memory. PMID:20519520

  16. LPS-induced systemic inflammation is more severe in P2Y12 null mice

    PubMed Central

    Liverani, Elisabetta; Rico, Mario C.; Yaratha, Laxmikausthubha; Tsygankov, Alexander Y.; Kilpatrick, Laurie E.; Kunapuli, Satya P.

    2014-01-01

    Thienopyridines are a class of antiplatelet drugs that are metabolized in the liver to several metabolites, of which only one active metabolite can irreversibly antagonize the platelet P2Y12 receptor. Possible effects of these drugs and the role of activated platelets in inflammatory responses have also been investigated in a variety of animal models, demonstrating that thienopyridines could alter inflammation. However, it is not clear whether it is caused only by the P2Y12 antagonism or whether off-target effects of other metabolites also intervene. To address this question, we investigated P2Y12 KO mice during a LPS-induced model of systemic inflammation, and we treated these KO mice with a thienopyridine drug (clopidogrel). Contrary to the reported effects of clopidogrel, numbers of circulating WBCs and plasma levels of cytokines were increased in LPS-exposed KO mice compared with WT in this inflammation model. Moreover, both spleen and bone marrow show an increase in cell content, suggesting a role for P2Y12 in regulation of bone marrow and spleen cellular composition. Finally, the injury was more severe in the lungs of KO mice compared with WT. Interestingly, clopidogrel treatments also exerted protective effects in KO mice, suggesting off-target effects for this drug. In conclusion, the P2Y12 receptor plays an important role during LPS-induced inflammation, and this signaling pathway may be involved in regulating cell content in spleen and bone marrow during LPS systemic inflammation. Furthermore, clopidogrel may have effects that are independent of P2Y12 receptor blockade. PMID:24142066

  17. Feeding, exploratory, anxiety- and depression-related behaviors are not altered in interleukin-6-deficient male mice

    PubMed Central

    Swiergiel, Artur H.; Dunn, Adrian J.

    2007-01-01

    Interleukin-6 (IL-6) has been implicated in behavioral responses associated with inflammation, sickness behavior and various nervous system disorders. We studied a range of different behaviors in IL-6-knockout (IL-6ko) and wild-type (WT) male mice. No significant differences were observed in ambulatory, exploratory, and stereotypic activities in home or novel cages, in an open field (OF), in the multicompartment chamber (MCC), or in the elevated plus-maze (EPM). IL-6ko mice shed fewer fecal boli than WT mice in the OF, in novel cages and in the MCC although this effect was not statistically significant in the OF. In novel cages, intraperitoneal (i.p.) injection of IL-6 (1 μg) depressed ambulatory activity slightly more in IL-6ko than in WT mice. Restraint and interleukin-1β (IL-1β, 100 ng i.p.) decreased exploration of mice in the MCC and EPM, but there was no indication of altered sensitivity in IL-6ko mice. No significant differences were detected in the tail suspension and the Porsolt forced swim tests. IL-1β and lipopolysaccharide (LPS 1 μg i.p.) injection depressed sweetened milk and solid food intake similarly in IL-6ko and WT mice, but IL-6 had no effect, suggesting that IL-6 is not involved in these effects of IL-1 or LPS. However, IL-1β and LPS depressed body weight more in WT than in IL-6ko mice. Plasma corticosterone and basal concentrations of catecholamines, indoleamines and their metabolites in several brain regions were similar. The responses in these measures to IL-1β and LPS were also similar, except that there were no significant changes in tryptophan and serotonin metabolism in IL-6ko mice. This may reflect a role for IL-6 in the tryptophan and serotonin responses to IL-1 and LPS. It is concluded that the lack of IL-6 is not associated with substantial alterations in several different mouse behaviors, and in the responses to restraint, IL-1β, IL-6 and LPS. PMID:16677721

  18. Glutathione-S-transferase A3 knockout mice are sensitive to acute cytotoxic and genotoxic effects of aflatoxin B1

    SciTech Connect

    Ilic, Zoran, E-mail: zxi01@health.state.ny.u; Crawford, Dana, E-mail: crawfod@mail.amc.ed; Egner, Patricia A., E-mail: pegner@jhsph.ed

    2010-02-01

    Aflatoxin B1 (AFB1) is a major risk factor for hepatocellular carcinoma (HCC) in humans. However, mice, a major animal model for the study of AFB1 carcinogenesis, are resistant, due to high constitutive expression, in the mouse liver, of glutathione S-transferase A3 subunit (mGSTA3) that is lacking in humans. Our objective was to establish that a mouse model for AFB1 toxicity could be used to study mechanisms of toxicity that are relevant for human disease, i.e., an mGSTA3 knockout (KO) mouse that responds to toxicants such as AFB1 in a manner similar to humans. Exons 3-6 of the mGSTA3 were replacedmore » with a neomycin cassette by homologous recombination. Southern blotting, RT-PCR, Western blotting, and measurement of AFB1-N{sup 7}-DNA adduct formation were used to evaluate the mGSTA3 KO mice. The KO mice have deletion of exons 3-6 of the mGSTA3 gene, as expected, as well as a lack of mGSTA3 expression at the mRNA and protein levels. Three hours after injection of 5 mg/kg AFB1, mGSTA3 KO mice have more than 100-fold more AFB1-N{sup 7}-DNA adducts in their livers than do similarly treated wild-type (WT) mice. In addition, the mGSTA3 KO mice die of massive hepatic necrosis, at AFB1 doses that have minimal toxic effects in WT mice. We conclude that mGSTA3 KO mice are sensitive to the acute cytotoxic and genotoxic effects of AFB1, confirming the crucial role of GSTA3 subunit in protection of normal mice against AFB1 toxicity. We propose the mGSTA3 KO mouse as a useful model with which to study the interplay of risk factors leading to HCC development in humans, as well as for testing of additional possible functions of mGSTA3.« less

  19. Endothelin receptor antagonist macitentan or deletion of mouse mast cell protease 4 delays lesion development in atherosclerotic mice.

    PubMed

    Houde, Martin; Desbiens, Louisane; Schwertani, Adel; Pejler, Gunnar; Iglarz, Marc; D'Orléans-Juste, Pedro

    2016-08-15

    To determine the impact of mixed endothelin receptor antagonist and mouse mast cell protease-4 (mMCP-4) in the development of atherosclerosis in the mouse model. Apolipoprotein E (ApoE) KO mice were crossed with mMCP-4 KO mice to generate ApoE/mMCP-4 double KO mice. Atherosclerosis was induced with a normal- or high-fat diet for 12, 27 or 52weeks. Macitentan (30mg/kg/day), a dual ETA/ETB receptor antagonist, was given orally for 6weeks (27week protocol). At sacrifice, aortas and brachiocephalic arteries (BCAs) were collected. En face Sudan IV staining was performed on aortas and BCA sections were subjected to Masson's trichrome stain and α-smooth muscle actin labeling. Under normal diet, both macitentan treatment and the absence of mMCP-4 reduced the development of aortic atherosclerotic lesions in 27-week old ApoE KO mice, but mMCP-4 deletion failed to maintain this effect on 52-week old mice. Under high-fat diet (WD), macitentan, but not the absence of mMCP-4, reduced aortic lesion development in ApoE KO mice. On BCA lesions of 27-week old WD mice, macitentan treatment had a small impact while mMCP-4 deletion showed improved features of plaque stability. These results suggest that the inhibition of mMCP-4 reduces lesion spreading in the earlier phases of atherosclerosis development and can help stabilise the more advanced plaque. Macitentan treatment was more effective to prevent lesion spreading but did not improve plaque features to the same extent. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Unaltered Hypothalamic Metabolic Gene Expression in Kiss1r Knockout Mice Despite Obesity and Reduced Energy Expenditure.

    PubMed

    De Bond, Julie-Ann P; Tolson, Kristen P; Nasamran, Chanond; Kauffman, Alexander S; Smith, Jeremy T

    2016-10-01

    Kisspeptin controls reproduction by stimulating gonadotrophin-releasing hormone neurones via its receptor Kiss1r. Kiss1r is also expressed other brain areas and in peripheral tissues, suggesting additional nonreproductive roles. We recently determined that Kiss1r knockout (KO) mice develop an obese and diabetic phenotype. In the present study, we investigated whether Kiss1r KOs develop this metabolic phenotype as a result of alterations in the expression of metabolic genes involved in the appetite regulating system of the hypothalamus, including neuropeptide Y (Npy) and pro-opiomelanocortin (Pomc), as well as leptin receptor (Lepr), ghrelin receptor (Ghsr), and melanocortin receptors 3 and 4 (Mc3r, Mc4r). Body weights, leptin levels and hypothalamic gene expression were measured in both gonad-intact and gonadectomised (GNX) mice at 8 and 20 weeks of age that had received either normal chow or a high-fat diet. We detected significant increases in Pomc expression in gonad-intact Kiss1r KO mice at 8 and 20 weeks, although there were no alterations in the other metabolic-related genes. However, the Pomc increases appeared to reflect genotype differences in circulating sex steroids, because GNX wild-type and Kiss1r KO mice exhibited similar Pomc levels, along with similar Npy levels. The altered Pomc gene expression in gonad-intact Kiss1r KO mice is consistent with previous reports of reduced food intake in these mice and may serve to increase the anorexigenic drive, perhaps compensating for the obese state. However, the surprising overall lack of changes in any of the hypothalamic metabolic genes in GNX KO mice suggests that the aetiology of obesity in the absence of kisspeptin signalling may reflect peripheral rather than central metabolic impairments. © 2016 British Society for Neuroendocrinology.

  1. Increased Metabotropic Glutamate Receptor 5 Signaling Underlies Obsessive-Compulsive Disorder-like Behavioral and Striatal Circuit Abnormalities in Mice.

    PubMed

    Ade, Kristen K; Wan, Yehong; Hamann, Harold C; O'Hare, Justin K; Guo, Weirui; Quian, Anna; Kumar, Sunil; Bhagat, Srishti; Rodriguiz, Ramona M; Wetsel, William C; Conn, P Jeffrey; Dzirasa, Kafui; Huber, Kimberly M; Calakos, Nicole

    2016-10-01

    Development of treatments for obsessive-compulsive disorder (OCD) is hampered by a lack of mechanistic understanding about this prevalent neuropsychiatric condition. Although circuit changes such as elevated frontostriatal activity are linked to OCD, the underlying molecular signaling that drives OCD-related behaviors remains largely unknown. Here, we examine the significance of type 5 metabotropic glutamate receptors (mGluR5s) for behavioral and circuit abnormalities relevant to OCD. Sapap3 knockout (KO) mice treated acutely with an mGluR5 antagonist were evaluated for OCD-relevant phenotypes of self-grooming, anxiety-like behaviors, and increased striatal activity. The role of mGluR5 in the striatal circuit abnormalities of Sapap3 KO mice was further explored using two-photon calcium imaging to monitor striatal output from the direct and indirect pathways. A contribution of constitutive signaling to increased striatal mGluR5 activity in Sapap3 KO mice was investigated using pharmacologic and biochemical approaches. Finally, sufficiency of mGluR5 to drive OCD-like behavior in wild-type mice was tested by potentiating mGluR5 with a positive allosteric modulator. Excessive mGluR5 signaling underlies OCD-like behaviors and striatal circuit abnormalities in Sapap3 KO mice. Accordingly, enhancing mGluR5 activity acutely recapitulates these behavioral phenotypes in wild-type mice. In Sapap3 KO mice, elevated mGluR5 signaling is associated with constitutively active receptors and increased and imbalanced striatal output that is acutely corrected by antagonizing striatal mGluR5. These findings demonstrate a causal role for increased mGluR5 signaling in driving striatal output abnormalities and behaviors with relevance to OCD and show the tractability of acute mGluR5 inhibition to remedy circuit and behavioral abnormalities. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  2. Central ghrelin signaling mediates the metabolic response of C57BL/6 male mice to chronic social defeat stress.

    PubMed

    Patterson, Z R; Khazall, R; Mackay, H; Anisman, H; Abizaid, A

    2013-03-01

    Chronic stressors promote metabolic disturbances, including obesity and metabolic syndrome. Ghrelin, a peptide that promotes appetite and the accumulation of adipose tissue, is also secreted in response to stressors to protect the brain and peripheral tissues from the effects of these stressors. Here we demonstrate that elevated ghrelin levels produced by chronic exposure to social stress are associated with increased caloric intake and body weight gain in male C57BL mice. In contrast, stressed mice lacking ghrelin receptors (GHSR KO mice) or C57BL mice receiving chronic intracerebroventricular delivery of the ghrelin receptor antagonist [d-Lys(3)]-GHRP-6 show attenuated weight gain and feeding responses under the same social stress paradigm. Interestingly, stressed GHSR KO mice showed depleted sc and intrascapular brown fat depots, whereas stressed young wild-type mice did not. In old wild-type mice, chronic social defeat increased visceral and intrascapular brown fat depots in association with increases in obesity markers like hyperleptinemia and hyperinsulinemia along with increased hypothalamic expression of neuropeptide Y and Agouti related peptide. Importantly, the elevated expression of these peptides persisted least for 2 weeks after cessation of the stressor regimen. In contrast, old GHSR KO mice did not show these alterations after chronic social defeat. These results suggest that ghrelin plays an important role in the metabolic adaptations necessary to meet the energetic demands posed by stressors, but chronic exposure to stress-induced ghrelin elevations ultimately could lead to long lasting metabolic dysfunctions.

  3. Increased a-series gangliosides positively regulate leptin/Ob receptor-mediated signals in hypothalamus of GD3 synthase-deficient mice.

    PubMed

    Ji, Shuting; Tokizane, Kyohei; Ohkawa, Yuki; Ohmi, Yuhsuke; Banno, Ryoichi; Okajima, Tetsuya; Kiyama, Hiroshi; Furukawa, Koichi; Furukawa, Keiko

    2016-10-21

    Gangliosides are widely involved in the regulation of cells and organs. However, little is known about their roles in adipose tissues and hypothalamus. In GD3 synthase-knockout (GD3S KO) mice, deletion of b-series gangliosides resulted in the reduction of serum leptin due to disturbed secretion from adipocytes. To examine whether leptin signals altered, leptin/leptin receptor (ObR)-mediated signaling in hypothalamus was analyzed. Hypothalamus of GD3S KO mouse showed increased expression of GM1 and GD1a, and increased activation of ObR-mediated signals such as pSTAT3 and c-Fos. Leptin stimulation of hypothalamus-derived N-41 cells and their transfectants with GD3S cDNA showed that a-series gangliosides positively regulate leptin/ObR-mediated signals. Co-precipitation analysis revealed that ObR interacts with a-series gangliosides with increased association by leptin stimulation. In brown adipose tissues (BAT) of GD3S KO mice, their weights and adipocyte numbers were increased, and BAT markers such as PGC1α and UCP-1 were also up-regulated. These results suggested that leptin/ObRb-mediated signals were enhanced in hypothalamus of GD3S KO mice due to increased a-series gangliosides, leading to the apparently similar features of energy expenditure between the KO and wild type mice. Copyright © 2016 Elsevier Inc. All rights reserved.

  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. Selegiline Ameliorates Depression-Like Behavior in Mice Lacking the CD157/BST1 Gene, a Risk Factor for Parkinson’s Disease

    PubMed Central

    Kasai, Satoka; Yoshihara, Toru; Lopatina, Olga; Ishihara, Katsuhiko; Higashida, Haruhiro

    2017-01-01

    Parkinson’s disease (PD), a neurodegenerative disorder, is accompanied by various non-motor symptoms including depression and anxiety, which may precede the onset of motor symptoms. Selegiline is an irreversible monoamine oxidase-B (MAO-B) inhibitor, and is widely used in the treatment of PD and major depression. However, there are few reports about the effects of selegiline on non-motor symptoms in PD. The aim of this study was to explore the antidepressant and anxiolytic effects of selegiline, using CD157/BST1 knockout (CD157 KO) mouse, a PD-related genetic model displaying depression and anxiety, compared with other antiparkinsonian drugs and an antidepressant, and was to investigate the effects of selegiline on biochemical parameters in emotion-related brain regions. A single administration of selegiline (1–10 mg/kg) dose-dependently reduced immobility time in the forced swimming test (FST) in CD157 KO mice, but not C57BL/6N wild-type (WT) mice. At 10 mg/kg, but not 3 mg/kg, selegiline significantly increased climbing time in CD157 KO mice. A single administration of the antiparkinsonian drugs pramipexole (a dopamine (DA) D2/D3 receptor agonist) or rasagiline (another MAO-B inhibitor), and repeated injections of a noradrenergic and specific serotonergic antidepressant (NaSSA), mirtazapine, also decreased immobility time, but did not increase climbing time, in CD157 KO mice. The antidepressant-like effects of 10 mg/kg selegiline were comparable to those of 10 mg/kg rasagiline, and tended to be stronger than those of 1 mg/kg rasagiline. After the FST, CD157 KO mice showed decreases in striatal and hippocampal serotonin (5-HT) content, cortical norepinephrine (NE) content, and plasma corticosterone concentration. A single administration of selegiline at 10 mg/kg returned striatal 5-HT, cortical NE, and plasma corticosterone levels to those observed in WT mice. In the open field test (OFT), repeated administration of mirtazapine had anxiolytic effects, and

  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. Deletion of nuclear factor-κB p50 upregulates fatty acid utilization and contributes to an anti-obesity and high-endurance phenotype in mice.

    PubMed

    Minegishi, Yoshihiko; Haramizu, Satoshi; Misawa, Koichi; Shimotoyodome, Akira; Hase, Tadashi; Murase, Takatoshi

    2015-09-15

    The transcription factor nuclear factor-κB (NF-κB) plays an important role in regulating physiological processes such as immunity and inflammation. In addition to this primary role, NF-κB interacts physically with peroxisome proliferator-activated receptors regulating lipid metabolism-related gene expression and inhibits their transcriptional activity. Therefore, inhibition of NF-κB may promote fatty acid utilization, which could ameliorate obesity and improve endurance capacity. To test this hypothesis, we attempted to elucidate the energy metabolic status of mice lacking the p50 subunit of NF-κB (p50 KO mice) from the tissue to whole body level. p50 KO mice showed a significantly lower respiratory quotient throughout the day than did wild-type (WT) mice; this decrease was associated with increased fatty acid oxidation activity in liver and gastrocnemius muscle of p50 KO mice. p50 KO mice that were fed a high-fat diet were also resistant to fat accumulation and adipose tissue inflammation. Furthermore, p50 KO mice showed a significantly longer maximum running time compared with WT mice, with a lower respiratory exchange ratio during exercise as well as higher residual muscle glycogen content and lower blood lactate levels after exercise. These results suggest that p50 deletion facilitates fatty acid catabolism, leading to an anti-obesity and high-endurance phenotype of mice and supporting the idea that NF-κB is an important regulator of energy metabolism. Copyright © 2015 the American Physiological Society.

  8. Genetic deletion of MT(1) and MT(2) melatonin receptors differentially abrogates the development and expression of methamphetamine-induced locomotor sensitization during the day and the night in C3H/HeN mice.

    PubMed

    Hutchinson, Anthony J; Hudson, Randall L; Dubocovich, Margarita L

    2012-11-01

    This study explored the role of the melatonin receptors in methamphetamine (METH)-induced locomotor sensitization during the light and dark phases in C3H/HeN mice with genetic deletion of the MT(1) and/or MT(2) melatonin receptors. Six daily treatments with METH (1.2 mg/kg, i.p.) in a novel environment during the light phase led to the development of locomotor sensitization in wild-type (WT), MT(1)KO and MT(2)KO mice. Following four full days of abstinence, METH challenge (1.2 mg/kg, i.p.) triggered the expression of locomotor sensitization in METH-pretreated but not in vehicle (VEH)-pretreated mice. In MT(1)/MT(2)KO mice, the development of sensitization during the light phase was significantly reduced and the expression of sensitization was completely abrogated upon METH challenge. During the dark phase the development of locomotor sensitization in METH-pretreated WT, MT(1)KO and MT(2)KO mice was statistically different from VEH-treated controls. However, WT and MT(2)KO, but not MT(1)KO mice receiving repeated VEH pretreatments during the dark phase expressed a sensitized response to METH challenge that is of an identical magnitude to that observed upon 6 days of METH pretreatment. We conclude that exposure to a novel environment during the dark phase, but not during the light phase, facilitated the expression of sensitization to a METH challenge in a manner dependent on MT(1) melatonin receptor activation by endogenous melatonin. We suggest that MT(1) and MT(2) melatonin receptors are potential targets for pharmacotherapeutic intervention in METH abusers. © 2012 John Wiley & Sons A/S.

  9. Uterine artery dysfunction in pregnant ACE2 knockout mice is associated with placental hypoxia and reduced umbilical blood flow velocity.

    PubMed

    Yamaleyeva, Liliya M; Pulgar, Victor M; Lindsey, Sarah H; Yamane, Larissa; Varagic, Jasmina; McGee, Carolynne; daSilva, Mauro; Lopes Bonfa, Paula; Gurley, Susan B; Brosnihan, K Bridget

    2015-07-01

    Angiotensin-converting enzyme 2 (ACE2) knockout is associated with reduced fetal weight at late gestation; however, whether uteroplacental vascular and/or hemodynamic disturbances underlie this growth-restricted phenotype is unknown. Uterine artery reactivity and flow velocities, umbilical flow velocities, trophoblast invasion, and placental hypoxia were determined in ACE2 knockout (KO) and C57Bl/6 wild-type (WT) mice at day 14 of gestation. Although systolic blood pressure was higher in pregnant ACE2 KO vs. WT mice (102.3 ± 5.1 vs. 85.1 ± 1.9 mmHg, n = 5-6), the magnitude of difference was similar to that observed in nonpregnant ACE2 KO vs. WT mice. Maternal urinary protein excretion, serum creatinine, and kidney or heart weights were not different in ACE2 KO vs. WT. Fetal weight and pup-to-placental weight ratio were lower in ACE2 KO vs. WT mice. A higher sensitivity to Ang II [pD2 8.64 ± 0.04 vs. 8.5 ± 0.03 (-log EC50)] and greater maximal contraction to phenylephrine (169.0 ± 9.0 vs. 139.0 ± 7.0% KMAX), were associated with lower immunostaining for Ang II receptor 2 and fibrinoid content of the uterine artery in ACE2 KO mice. Uterine artery flow velocities and trophoblast invasion were similar between study groups. In contrast, umbilical artery peak systolic velocities (60.2 ± 4.5 vs. 75.1 ± 4.5 mm/s) and the resistance index measured using VEVO 2100 ultrasound were lower in the ACE2 KO vs. WT mice. Immunostaining for pimonidazole, a marker of hypoxia, and hypoxia-inducible factor-2α were higher in the trophospongium and placental labyrinth of the ACE2 KO vs. WT. In summary, placental hypoxia and uterine artery dysfunction develop before major growth of the fetus occurs and may explain the fetal growth restricted phenotype. Copyright © 2015 the American Physiological Society.

  10. Differential roles of α6β2* and α4β2* neuronal nicotinic receptors in nicotine- and cocaine-conditioned reward in mice.

    PubMed

    Sanjakdar, Sarah S; Maldoon, Pretal P; Marks, Michael J; Brunzell, Darlene H; Maskos, Uwe; McIntosh, J Michael; Bowers, M Scott; Damaj, M Imad

    2015-01-01

    Mesolimbic α6* nicotinic acetylcholine receptors (nAChRs) are thought to have an important role in nicotine behavioral effects. However, little is known about the role of the various α6*-nAChRs subtypes in the rewarding effects of nicotine. In this report, we investigated and compared the role of α6*-nAChRs subtypes and their neuro-anatomical locus in nicotine and cocaine reward-like effects in the conditioned place preference (CPP) paradigm, using pharmacological antagonism of α6β2* nAChRs and genetic deletion of the α6 or α4 subunits in mice. We found that α6 KO mice exhibited a rightward shift in the nicotine dose-response curve compared with WT littermates but that α4 KO failed to show nicotine preference, suggesting that α6α4β2*-nAChRs are involved. Furthermore, α6β2* nAChRs in nucleus accumbens were found to have an important role in nicotine-conditioned reward as the intra-accumbal injection of the selective α6β2* α-conotoxin MII [H9A; L15A], blocked nicotine CPP. In contrast to nicotine, α6 KO failed to condition to cocaine, but cocaine CPP in the α4 KO was preserved. Intriguingly, α-conotoxin MII [H9A; L15A], blocked cocaine conditioning in α4 KO mice, implicating α6β2* nAChRs in cocaine reward. Importantly, these effects did not generalize as α6 KO showed both a conditioned place aversion to lithium chloride as well as CPP to palatable food. Finally, dopamine uptake was not different between the α6 KO or WT mice. These data illustrate that the subjective rewarding effects of both nicotine and cocaine may be mediated by mesolimbic α6β2* nAChRs and that antagonists of these receptor subtypes may exhibit therapeutic potential.

  11. Mice Deficient in STAT1 but Not STAT2 or IRF9 Develop a Lethal CD4+ T-Cell-Mediated Disease following Infection with Lymphocytic Choriomeningitis Virus

    PubMed Central

    Hofer, Markus J.; Li, Wen; Manders, Peter; Terry, Rachael; Lim, Sue Ling; King, Nicholas J. C.

    2012-01-01

    Interferon (IFN) signaling is crucial for antiviral immunity. While type I IFN signaling is mediated by STAT1, STAT2, and IRF9, type II IFN signaling requires only STAT1. Here, we studied the roles of these signaling factors in the host response to systemic infection with lymphocytic choriomeningitis virus (LCMV). In wild-type (WT) mice and mice lacking either STAT2 or IRF9, LCMV infection was nonlethal, and the virus either was cleared (WT) or established persistence (STAT2 knockout [KO] and IRF9 KO). However, in the case of STAT1 KO mice, LCMV infection was lethal and accompanied by severe multiorgan immune pathology, elevated expression of various cytokine genes in tissues, and cytokines in the serum. This lethal phenotype was unaltered by the coabsence of the gamma interferon (IFN-γ) receptor and hence was not dependent on IFN-γ. Equally, the disease was not due to a combined defect in type I and type II IFN signaling, as IRF9 KO mice lacking the IFN-γ receptor survived infection with LCMV. Clearance of LCMV is mediated normally by CD8+ T cells. However, the depletion of these cells in LCMV-infected STAT1 KO mice was delayed, but did not prevent, lethality. In contrast, depletion of CD4+ T cells prevented lethality in LCMV-infected STAT1 KO mice and was associated with a reduction in tissue immune pathology. These studies highlight a fundamental difference in the role of STAT1 versus STAT2 and IRF9. While all three factors are required to limit viral replication and spread, only STAT1 has the unique function of preventing the emergence of a lethal antiviral CD4+ T-cell response. PMID:22496215

  12. MAFB is dispensable for the fetal testis morphogenesis and the maintenance of spermatogenesis in adult mice

    PubMed Central

    Oishi, Hisashi; Usui, Toshiaki; Kitadate, Yu; Basha, Walaa A.; Abdellatif, Ahmed M.; Hasegawa, Kazunori; Okada, Risa; Mochida, Keiji; El-Shemy, Hany A.; Muratani, Masafumi; Ogura, Atsuo; Yoshida, Shosei; Takahashi, Satoru

    2018-01-01

    The transcription factor MAFB is an important regulator of the development and differentiation of various organs and tissues. Previous studies have shown that MAFB is expressed in embryonic and adult mouse testes and is expected to act as the downstream target of retinoic acid (RA) to initiate spermatogenesis. However, its exact localization and function remain unclear. Here, we localized MAFB expression in embryonic and adult testes and analyzed its gene function using Mafb-deficient mice. We found that MAFB and c-MAF are the only large MAF transcription factors expressed in testes, while MAFA and NRL are not. MAFB was localized in Leydig and Sertoli cells at embryonic day (E) 18.5 but in Leydig cells, Sertoli cells, and pachytene spermatocytes in adults. Mafb-deficient testes at E18.5 showed fully formed seminiferous tubules with no abnormal structure or differences in testicular somatic cell numbers compared with those of control wild-type mice. Additionally, the expression levels of genes related to development and function of testicular cells were unchanged between genotypes. In adults, the expression of MAFB in Sertoli cells was shown to be stage specific and induced by RA. By generating Mafbfl/fl CAG-CreER™ (Mafb-cKO) mice, in which Cre recombinase was activated upon tamoxifen treatment, we found that the neonatal cKO mice died shortly upon Mafb deletion, but adult cKO mice were alive upon deletion. Adult cKO mice were fertile, and spermatogenesis maintenance was normal, as indicated by histological analysis, hormone levels, and germ cell stage-specific markers. Moreover, there were no differences in the proportion of seminiferous stages between cKO mice and controls. However, RNA-Seq analysis of cKO Sertoli cells revealed that the down-regulated genes were related to immune function and phagocytosis activity but not spermatogenesis. In conclusion, we found that MAFB is dispensable for fetal testis morphogenesis and spermatogenesis maintenance in adult

  13. Monoamine oxidase A and A/B knockout mice display autistic-like features

    PubMed Central

    Bortolato, Marco; Godar, Sean C.; Alzghoul, Loai; Zhang, Junlin; Darling, Ryan D.; Simpson, Kimberly L.; Bini, Valentina; Chen, Kevin; Wellman, Cara L.; Lin, Rick C. S.; Shih, Jean C.

    2012-01-01

    Converging lines of evidence show that a sizable subset of autism-spectrum disorders (ASDs) is characterized by increased blood levels of serotonin (5-hydroxytryptamine, 5-HT), yet the mechanistic link between these two phenomena remains unclear. The enzymatic degradation of brain 5-HT is mainly mediated by monoamine oxidase (MAO)A and, in the absence of this enzyme, by its cognate isoenzyme MAOB. MAOA and A/B knockout (KO) mice display high 5-HT levels, particularly during early developmental stages. Here we show that both mutant lines exhibit numerous behavioural hallmarks of ASDs, such as social and communication impairments, perseverative and stereotypical responses, behavioural inflexibility, as well as subtle tactile and motor deficits. Furthermore, both MAOA and A/B KO mice displayed neuropathological alterations reminiscent of typical ASD features, including reduced thickness of the corpus callosum, increased dendritic arborization of pyramidal neurons in the prefrontal cortex and disrupted microarchitecture of the cerebellum. The severity of repetitive responses and neuropathological aberrances was generally greater in MAOA/B KO animals. These findings suggest that the neurochemical imbalances induced by MAOAdeficiency (either by itself or in conjunction with lack of MAOB) may result in an array of abnormalities similar to those observed in ASDs. Thus, MAOA and A/B KO mice may afford valuable models to help elucidate the neurobiological bases of these disorders and related neurodevelopmental problems. PMID:22850464

  14. SIRT1 Activation by Resveratrol Alleviates Cardiac Dysfunction via Mitochondrial Regulation in Diabetic Cardiomyopathy Mice

    PubMed Central

    Zhang, Ran; Chen, Jiangwei; Li, Xiang; Yang, Bo; Li, Xiujuan; Fan, Miaomiao; Li, Congye; Tian, Zuhong

    2017-01-01

    Background Diabetic cardiomyopathy (DCM) is a major threat for diabetic patients. Silent information regulator 1 (SIRT1) has a regulatory effect on mitochondrial dynamics, which is associated with DCM pathological changes. Our study aims to investigate whether resveratrol, a SRIT1 activator, could exert a protective effect against DCM. Methods and Results Cardiac-specific SIRT1 knockout (SIRT1KO) mice were generated using Cre-loxP system. SIRT1KO mice displayed symptoms of DCM, including cardiac hypertrophy and dysfunction, insulin resistance, and abnormal glucose metabolism. DCM and SIRT1KO hearts showed impaired mitochondrial biogenesis and function, while SIRT1 activation by resveratrol reversed this in DCM mice. High glucose caused increased apoptosis, impaired mitochondrial biogenesis, and function in cardiomyocytes, which was alleviated by resveratrol. SIRT1 deletion by both SIRT1KO and shRNA abolished the beneficial effects of resveratrol. Furthermore, the function of SIRT1 is mediated via the deacetylation effect on peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), thus inducing increased expression of nuclear respiratory factor 1 (NRF-1), NRF-2, estrogen-related receptor-α (ERR-α), and mitochondrial transcription factor A (TFAM). Conclusions Cardiac deletion of SIRT1 caused phenotypes resembling DCM. Activation of SIRT1 by resveratrol ameliorated cardiac injuries in DCM through PGC-1α-mediated mitochondrial regulation. Collectively, SIRT1 may serve as a potential therapeutic target for DCM. PMID:28883902

  15. Ethanol-related behaviors in mice lacking the sigma-1 receptor

    PubMed Central

    Valenza, Marta; DiLeo, Alyssa; Steardo, Luca; Cottone, Pietro; Sabino, Valentina

    2015-01-01

    Rationale The Sigma-1 receptor (Sig-1R) is a chaperone protein that has been implicated in drug abuse and addiction. Multiple studies have characterized the role the Sig-1R plays in psychostimulants addiction, but fewer studies have specifically investigated its role in alcohol addiction. We have previously shown that antagonism of the Sig-1R reduces excessive drinking and motivation to drink, whereas agonism induces binge-like drinking in rodents. Objectives The objectives of these studies were to investigate the impact of Sig-1R gene deletion in C57Bl/6J mice on ethanol drinking and other ethanol-related behaviors. Methods We used an extensive panel of behavioral tests to examine ethanol actions in male, adult mice lacking Oprs1, the gene encoding the Sig-1R. To compare ethanol drinking behavior, Sig-1 knockout (KO) and wild type (WT) mice were subject to a two-bottle choice, continuous access paradigm with different concentrations of ethanol (3%–20% v/v) vs. water. Consumption of sweet and bitter solutions was also assessed in Sig-1R KO and WT mice. Finally, motor stimulant sensitivity, taste aversion and ataxic effects of ethanol were assessed. Results Sig-1R KO mice displayed higher ethanol intake compared to WT mice; the two genotypes did not differ in their sweet or bitter taste perception. Sig-1R KO mice showed lower sensitivity to ethanol stimulant effects, but greater sensitivity to its taste aversive effects. Ethanol-induced sedation was unaltered in the mutants. Conclusions Our results suggest that the deletion of the Sig-1R increases ethanol consumption, likely by decreasing its rewarding effects, and therefore indicating that the Sig-1R is involved in modulation of the reinforcing effects of alcohol. PMID:26462569

  16. Alkyl-glycerol rescues plasmalogen levels and pathology of ether-phospholipid deficient mice.

    PubMed

    Brites, Pedro; Ferreira, Ana Sofia; da Silva, Tiago Ferreira; Sousa, Vera F; Malheiro, Ana R; Duran, Marinus; Waterham, Hans R; Baes, Myriam; Wanders, Ronald J A

    2011-01-01

    A deficiency of plasmalogens, caused by impaired peroxisomal metabolism affects normal development and multiple organs in adulthood. Treatment options aimed at restoring plasmalogen levels may be relevant for the therapy of peroxisomal and non-peroxisomal disorders. In this study we determined the in vivo efficacy of an alkyl glycerol (AG), namely, 1-O-octadecyl-rac-glycerol, as a therapeutic agent for defects in plasmalogen synthesis. To achieve this, Pex7 knockout mice, a mouse model for Rhizomelic Chondrodysplasia Punctata type 1 characterized by the absence of plasmalogens, and WT mice were fed a control diet or a diet containing 2% alkyl-glycerol. Plasmalogen levels were measured in target organs and the biochemical data were correlated with the histological analysis of affected organs. Plasmalogen levels in all peripheral tissues of Pex7 KO mice fed the AG diet for 2 months normalized to the levels of AG fed WT mice. In nervous tissues of Pex7 KO mice fed the AG-diet, plasmalogen levels were significantly increased compared to control fed KO mice. Histological analysis of target organs revealed that the AG-diet was able to stop the progression of the pathology in testis, adipose tissue and the Harderian gland. Interestingly, the latter tissues are characterized by the presence of lipid droplets which were absent or reduced in size and number when ether-phospholipids are lacking, but which can be restored with the AAG treatment. Furthermore, nerve conduction in peripheral nerves was improved. When given prior to the occurrence of major pathological changes, the AG-diet prevented or ameliorated the pathology observed in Pex7 KO mice depending on the degree of plasmalogen restoration. This study provides evidence of the beneficial effects of treating a plasmalogen deficiency with alkyl-glycerol.

  17. Alkyl-Glycerol Rescues Plasmalogen Levels and Pathology of Ether-Phospholipid Deficient Mice

    PubMed Central

    Brites, Pedro; Ferreira, Ana Sofia; Ferreira da Silva, Tiago; Sousa, Vera F.; Malheiro, Ana R.; Duran, Marinus; Waterham, Hans R.; Baes, Myriam; Wanders, Ronald J. A.

    2011-01-01

    A deficiency of plasmalogens, caused by impaired peroxisomal metabolism affects normal development and multiple organs in adulthood. Treatment options aimed at restoring plasmalogen levels may be relevant for the therapy of peroxisomal and non-peroxisomal disorders. In this study we determined the in vivo efficacy of an alkyl glycerol (AG), namely, 1-O-octadecyl-rac-glycerol, as a therapeutic agent for defects in plasmalogen synthesis. To achieve this, Pex7 knockout mice, a mouse model for Rhizomelic Chondrodysplasia Punctata type 1 characterized by the absence of plasmalogens, and WT mice were fed a control diet or a diet containing 2% alkyl-glycerol. Plasmalogen levels were measured in target organs and the biochemical data were correlated with the histological analysis of affected organs. Plasmalogen levels in all peripheral tissues of Pex7 KO mice fed the AG diet for 2 months normalized to the levels of AG fed WT mice. In nervous tissues of Pex7 KO mice fed the AG-diet, plasmalogen levels were significantly increased compared to control fed KO mice. Histological analysis of target organs revealed that the AG-diet was able to stop the progression of the pathology in testis, adipose tissue and the Harderian gland. Interestingly, the latter tissues are characterized by the presence of lipid droplets which were absent or reduced in size and number when ether-phospholipids are lacking, but which can be restored with the AAG treatment. Furthermore, nerve conduction in peripheral nerves was improved. When given prior to the occurrence of major pathological changes, the AG-diet prevented or ameliorated the pathology observed in Pex7 KO mice depending on the degree of plasmalogen restoration. This study provides evidence of the beneficial effects of treating a plasmalogen deficiency with alkyl-glycerol. PMID:22163031

  18. Ethanol-related behaviors in mice lacking the sigma-1 receptor.

    PubMed

    Valenza, Marta; DiLeo, Alyssa; Steardo, Luca; Cottone, Pietro; Sabino, Valentina

    2016-01-15

    The Sigma-1 receptor (Sig-1R) is a chaperone protein that has been implicated in drug abuse and addiction. Multiple studies have characterized the role the Sig-1R plays in psychostimulant addiction; however, fewer studies have specifically investigated its role in alcohol addiction. We have previously shown that antagonism of the Sig-1R reduces excessive drinking and motivation to drink, whereas agonism induces binge-like drinking in rodents. The objectives of these studies were to investigate the impact of Sig-1R gene deletion in C57Bl/6J mice on ethanol drinking and other ethanol-related behaviors. We used an extensive panel of behavioral tests to examine ethanol actions in male, adult mice lacking Oprs1, the gene encoding the Sig-1R. To compare ethanol drinking behavior, Sig-1 knockout (KO) and wild type (WT) mice were subject to a two-bottle choice, continuous access paradigm with different concentrations of ethanol (3-20% v/v) vs. water. Consumption of sweet and bitter solutions was also assessed in Sig-1R KO and WT mice. Finally, motor stimulant sensitivity, taste aversion and ataxic effects of ethanol were assessed. Sig-1R KO mice displayed higher ethanol intake compared to WT mice; the two genotypes did not differ in their sweet or bitter taste perception. Sig-1R KO mice showed lower sensitivity to ethanol stimulant effects, but greater sensitivity to its taste aversive effects. Ethanol-induced sedation was instead unaltered in the mutants. Our results prove that the deletion of the Sig-1R increases ethanol consumption, likely by decreasing its rewarding effects, and therefore indicating that the Sig-1R is involved in modulation of the reinforcing effects of alcohol. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Podocyte-specific deletion of Rac1 leads to aggravation of renal injury in STZ-induced diabetic mice

    SciTech Connect

    Ishizaka, Masanori; Gohda, Tomohito, E-mail: goda@juntendo.ac.jp; Takagi, Miyuki

    2015-11-20

    Rac1, a GTPase of the Rho subfamily, has a crucial role in cytoskeletal architecture, as well as the regulation of cell migration and growth. However, renal injury in mice with podocyte-specific deletion of Rac1 has yet to be elucidated fully due to conflicting findings. Herein, we identified a possible role for Rac1 in podocytes of streptozotocin- (STZ) induced diabetic mice. The urinary albumin/creatinine ratio (ACR) in the knockout (KO) group was significantly higher than that in the wild type (WT) group at any week of age. A more marked ACR increase was observed in STZ/KO group than STZ/WT group, althoughmore » ACR did increase with weeks of age in both diabetic groups. The kidney sections from diabetic mice revealed a glomerular hypertrophy with mesangial expansion, but there was no appreciable difference in glomerular findings under a light microscope between STZ/WT and STZ/KO mice. However, an electron microscopy analysis revealed that regardless of the presence or absence of diabetes, both KO (KO and STZ/KO) groups had a higher rate of foot process effacement compared with both WT (WT and STZ/WT) groups. The expression levels of the slit diaphragm protein, podocin, was reduced with the induction of diabetes, and the levels in the STZ/KO group experienced a further reduction compared with the STZ/WT group. The number of WT1-positive cells in the STZ/KO group was more significantly decreased than that in the other three groups. In contrast, the numbers of cleaved caspase 3- and TUNEL-positive cells in the glomeruli of the STZ/KO group were more increased than those in the STZ/WT group. Thus, this study provides evidence that podocyte-specific deletion of Rac1 results in morphological alteration in podocytes, and that the induction of apoptosis or decreased expression of the slit diaphragm proteins by hyperglycemic stimuli are associated with the progression of diabetic nephropathy.« less

  20. 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.

  1. Incorporation of Half-Cycle Theory Into Ko Aging Theory for Aerostructural Flight-Life Predictions

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Tran, Van T.; Chen, Tony

    2007-01-01

    The half-cycle crack growth theory was incorporated into the Ko closed-form aging theory to improve accuracy in the predictions of operational flight life of failure-critical aerostructural components. A new crack growth computer program was written for reading the maximum and minimum loads of each half-cycle from the random loading spectra for crack growth calcul