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B H Berg - One of the best experts on this subject based on the ideXlab platform.
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autophosphorylation of degradation products of arginyl trna synthetase protein isolated from bom NMRI Mouse liver
Iubmb Life, 1993Co-Authors: B H BergAbstract:Abstract Proteins of M(r) 140, 60, 57, 50, 22, and 14 kDa, all possessing arginyl-tRNA synthetase activity, were subjected to phosphorylation without addition of exogenous protein kinase activity. All proteins except the 14 kDa were shown to contain endogenous protein kinase activity. The product of autophosphorylation of the 60, 57, 50, and 22 kDa proteins was identified as a phosphorylated 14.9 kDa molecule. In some cases higher molecular weight phosphorylated proteins were also detected. Properties of the 60 kDa species are described.
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purification of aminoacyl trna synthetase kinase activities associated with threonyl and tyrosyl trna synthetases isolated from bom NMRI Mouse liver
Iubmb Life, 1993Co-Authors: B H BergAbstract:Aminoacyl-tRNA synthetase kinase activities and aminoacyl-tRNA synthetase activities prepared from postribosomal supernatants of Bom:NMRI Mouse liver comigrated through the following purification steps: 1 a) gel filtration on Sephadex G-200, 1 b) chromatofocusing, 2) affinity chromatography on immobilised total tRNA (mixture of tRNA's, specific for all aminoacyl-tRNA synthetases) and 3) affinity chromatography on immobilised tRNA, specific for each of threonyl- and tyrosyl-tRNA synthetases. The purification factors for threonyl- and tyrosyl-tRNA synthetases were about 17000x. The purified synthetases showed only one protein band following sodium dodecyl sulphate polyacrylamide gel electrophoresis. The purified threonyl- and tyrosyl-tRNA synthetase proteins were found also to possess threonyl- and tyrosyl-tRNA synthetase kinase activities, respectively. The purification of tRNA(Thr) and tRNA(Tyr) as well as a method for the renaturation and identification of threonyl- and tyrosyl-tRNA synthetase activities in protein bands obtained by SDS PAGE are described.
Mohammad Mehdi Mofatteh - One of the best experts on this subject based on the ideXlab platform.
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an effort toward molecular biology of food deprivation induced food hoarding in gonadectomized NMRI Mouse model focus on neural oxidative status
BMC Neuroscience, 2018Co-Authors: Noushin Nikray, Isaac Karimi, Zahraminoosh Siavashhaghighi, Lora A. Becker, Mohammad Mehdi MofattehAbstract:Environmental uncertainty, such as food deprivation, may alter internal milieu of nervous system through various mechanisms. In combination with circumstances of stress or aging, high consumption of unsaturated fatty acids and oxygen can make neural tissues sensitive to oxidative stress (OS). For adult rats, diminished level of gonadal steroid hormones accelerates OS and may result in special behavioral manifestations. This study was aimed to partially answer the question whether OS mediates trade-off between food hoarding and food intake (fat hoarding) in environmental uncertainty (e.g., fluctuations in food resource) within gonadectomized Mouse model in the presence of food deprivation-induced food hoarding behavior. Hoarding behavior was not uniformly expressed in all male mice that exposed to food deprivation. Extended phenotypes including hoarder and non-hoarder mice stored higher and lower amounts of food respectively as compared to that of low-hoarder mice (normal phenotype) after food deprivation. Results showed that neural oxidative status was not changed in the presence of hoarding behavior in gonadectomized mice regardless of tissue type, however, glutathione levels of brain tissues were increased in the presence of hoarding behavior. Decreased superoxide dismutase activity in brain and spinal cord tissues and increased malondialdehyde in brain tissues of gonadectomized mice were also seen. Although, food deprivation-induced hoarding behavior is a strategic response to food shortage in mice, it did not induce the same amount of hoarding across all colony mates. Hoarding behavior, in this case, is a response to the environmental uncertainty of food shortage, therefore is not an abnormal behavior. Hoarding behavior induced neural OS with regard to an increase in brain glutathione levels but failed to show other markers of neural OS. Decreased superoxide dismutase activity in brain and spinal cord tissues and increased malondialdehyde levels in brain tissues of gonadectomized mice could be a hallmark of debilitated antioxidative defense and more lipid peroxidation due to reduced amount of gonadal steroid hormones during aging.
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An effort toward molecular biology of food deprivation induced food hoarding in gonadectomized NMRI Mouse model: focus on neural oxidative status
BMC, 2018Co-Authors: Noushin Nikray, Isaac Karimi, Zahraminoosh Siavashhaghighi, Lora A. Becker, Mohammad Mehdi MofattehAbstract:Abstract Background Environmental uncertainty, such as food deprivation, may alter internal milieu of nervous system through various mechanisms. In combination with circumstances of stress or aging, high consumption of unsaturated fatty acids and oxygen can make neural tissues sensitive to oxidative stress (OS). For adult rats, diminished level of gonadal steroid hormones accelerates OS and may result in special behavioral manifestations. This study was aimed to partially answer the question whether OS mediates trade-off between food hoarding and food intake (fat hoarding) in environmental uncertainty (e.g., fluctuations in food resource) within gonadectomized Mouse model in the presence of food deprivation-induced food hoarding behavior. Results Hoarding behavior was not uniformly expressed in all male mice that exposed to food deprivation. Extended phenotypes including hoarder and non-hoarder mice stored higher and lower amounts of food respectively as compared to that of low-hoarder mice (normal phenotype) after food deprivation. Results showed that neural oxidative status was not changed in the presence of hoarding behavior in gonadectomized mice regardless of tissue type, however, glutathione levels of brain tissues were increased in the presence of hoarding behavior. Decreased superoxide dismutase activity in brain and spinal cord tissues and increased malondialdehyde in brain tissues of gonadectomized mice were also seen. Conclusions Although, food deprivation-induced hoarding behavior is a strategic response to food shortage in mice, it did not induce the same amount of hoarding across all colony mates. Hoarding behavior, in this case, is a response to the environmental uncertainty of food shortage, therefore is not an abnormal behavior. Hoarding behavior induced neural OS with regard to an increase in brain glutathione levels but failed to show other markers of neural OS. Decreased superoxide dismutase activity in brain and spinal cord tissues and increased malondialdehyde levels in brain tissues of gonadectomized mice could be a hallmark of debilitated antioxidative defense and more lipid peroxidation due to reduced amount of gonadal steroid hormones during aging
Isaac Karimi - One of the best experts on this subject based on the ideXlab platform.
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an effort toward molecular biology of food deprivation induced food hoarding in gonadectomized NMRI Mouse model focus on neural oxidative status
BMC Neuroscience, 2018Co-Authors: Noushin Nikray, Isaac Karimi, Zahraminoosh Siavashhaghighi, Lora A. Becker, Mohammad Mehdi MofattehAbstract:Environmental uncertainty, such as food deprivation, may alter internal milieu of nervous system through various mechanisms. In combination with circumstances of stress or aging, high consumption of unsaturated fatty acids and oxygen can make neural tissues sensitive to oxidative stress (OS). For adult rats, diminished level of gonadal steroid hormones accelerates OS and may result in special behavioral manifestations. This study was aimed to partially answer the question whether OS mediates trade-off between food hoarding and food intake (fat hoarding) in environmental uncertainty (e.g., fluctuations in food resource) within gonadectomized Mouse model in the presence of food deprivation-induced food hoarding behavior. Hoarding behavior was not uniformly expressed in all male mice that exposed to food deprivation. Extended phenotypes including hoarder and non-hoarder mice stored higher and lower amounts of food respectively as compared to that of low-hoarder mice (normal phenotype) after food deprivation. Results showed that neural oxidative status was not changed in the presence of hoarding behavior in gonadectomized mice regardless of tissue type, however, glutathione levels of brain tissues were increased in the presence of hoarding behavior. Decreased superoxide dismutase activity in brain and spinal cord tissues and increased malondialdehyde in brain tissues of gonadectomized mice were also seen. Although, food deprivation-induced hoarding behavior is a strategic response to food shortage in mice, it did not induce the same amount of hoarding across all colony mates. Hoarding behavior, in this case, is a response to the environmental uncertainty of food shortage, therefore is not an abnormal behavior. Hoarding behavior induced neural OS with regard to an increase in brain glutathione levels but failed to show other markers of neural OS. Decreased superoxide dismutase activity in brain and spinal cord tissues and increased malondialdehyde levels in brain tissues of gonadectomized mice could be a hallmark of debilitated antioxidative defense and more lipid peroxidation due to reduced amount of gonadal steroid hormones during aging.
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A high-fat diet induced NMRI Mouse model of metabolic syndrome: focus on brain-derived neurotrophic factor (BDNF)
Metabolic Brain Disease, 2018Co-Authors: Isaac Karimi, Shima Motamedi, Fatemeh RanjbarAbstract:The association of brain-derived neurotrophic factor (BDNF) as a member of neurotrophin family and metabolic syndrome (MetS) has been proposed, however basic evidence necessary to prove (or disprove) this association in non-genetic animal model is rare. Therefore, we investigated the alteration of encephalic BDNF gene expression in a Mouse model of high-fat diet (HFD) induced MetS. To translate MetS, male NMRI mice (9 weeks old; N = 13) fed on a HFD including suet powder (37.50%) and granulated sugar (19.85%) while control mice were fed a diet contained suet powder (6.25%) and granulated sugar (49.09%). We monitored the development of MetS by measuring fasting blood sugar (FBS) and lipid (total cholesterol (TC) and triacylglycerol (TGs)) and lipoprotein (high-density lipoprotein cholesterol (HDL-C), very low-density lipoprotein cholesterol (VLDL-C)) profiles, atherogenic index (AI), and somatic indices after 1 and 3 months of dietary interventions. The HFD intake led to increased body weight, liver weight, FBS, TC, and decreased HDL-C as compared to chow diet in mice after first month of dietary intervention. The increased FBS, body weight, abdominal fat mass, TGs, TC, and VLDL-C and decreased HDL-C were observed in HFD-fed mice as compared to those of chow-fed mice at 3th month. The statistical comparison of two HFD groups in two time intervals of 1st and 3th month confirmed that our HFD-induced MetS model was reliable because FBS, TGs and VLDL-C, TC, and AI have been increased significantly during selected time intervals. The AI increased significantly in HFD-fed mice compared to chow-fed mice after 3 months. The AI in HFD-fed mice treated with HFD for 3 months was increased significantly as compared to mice fed HFD for 1 month. Our diet-induced model more closely mimics the changes observed in human MetS and showed that encephalic BDNF gene in mice fed HFD was under-expressed by 0.30 fold with respect to chow-fed mice after 3 months of dietary intervention.
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An effort toward molecular biology of food deprivation induced food hoarding in gonadectomized NMRI Mouse model: focus on neural oxidative status
BMC, 2018Co-Authors: Noushin Nikray, Isaac Karimi, Zahraminoosh Siavashhaghighi, Lora A. Becker, Mohammad Mehdi MofattehAbstract:Abstract Background Environmental uncertainty, such as food deprivation, may alter internal milieu of nervous system through various mechanisms. In combination with circumstances of stress or aging, high consumption of unsaturated fatty acids and oxygen can make neural tissues sensitive to oxidative stress (OS). For adult rats, diminished level of gonadal steroid hormones accelerates OS and may result in special behavioral manifestations. This study was aimed to partially answer the question whether OS mediates trade-off between food hoarding and food intake (fat hoarding) in environmental uncertainty (e.g., fluctuations in food resource) within gonadectomized Mouse model in the presence of food deprivation-induced food hoarding behavior. Results Hoarding behavior was not uniformly expressed in all male mice that exposed to food deprivation. Extended phenotypes including hoarder and non-hoarder mice stored higher and lower amounts of food respectively as compared to that of low-hoarder mice (normal phenotype) after food deprivation. Results showed that neural oxidative status was not changed in the presence of hoarding behavior in gonadectomized mice regardless of tissue type, however, glutathione levels of brain tissues were increased in the presence of hoarding behavior. Decreased superoxide dismutase activity in brain and spinal cord tissues and increased malondialdehyde in brain tissues of gonadectomized mice were also seen. Conclusions Although, food deprivation-induced hoarding behavior is a strategic response to food shortage in mice, it did not induce the same amount of hoarding across all colony mates. Hoarding behavior, in this case, is a response to the environmental uncertainty of food shortage, therefore is not an abnormal behavior. Hoarding behavior induced neural OS with regard to an increase in brain glutathione levels but failed to show other markers of neural OS. Decreased superoxide dismutase activity in brain and spinal cord tissues and increased malondialdehyde levels in brain tissues of gonadectomized mice could be a hallmark of debilitated antioxidative defense and more lipid peroxidation due to reduced amount of gonadal steroid hormones during aging
Annette Koppschneider - One of the best experts on this subject based on the ideXlab platform.
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malignant progression of papillomas induced by the initiation promotion protocol in NMRI Mouse skin
Carcinogenesis, 1995Co-Authors: Gerhard Furstenberger, Annette KoppschneiderAbstract:Recording of individual responses to initiation - promotion was used to study the relationship between papilloma and carcinoma formation in NMRI Mouse skin. This type of analysis is without precedent in that it allows a statistical evaluation of the data which was impossible with previously published analyses based upon cumulative tumor response data evaluated in other Mouse strains. Initiation with DMBA and promotion with TPA yielded papillomas consisting of two sub-populations, reversible and persistent papillomas. The ratio of persisting to reversible papillomas was independent of the duration of promotion, indicating comparable growth rates for both types of papillomas. Fifty percent of the persistent and 4% of all papillomas progressed into carcinomas. Promotion for >20 weeks increased neither the total number of papillomas nor the number of carcinomas. Both the maximum number of persistent and the maximum number of reversible papillomas correlated with the risk of malignant progression, excluding persistent papillomas as being the exclusive precursor lesions for malignant progression
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carcinoma formation in NMRI Mouse skin painting studies is a process suggesting greater than two stages
Carcinogenesis, 1995Co-Authors: Annette Koppschneider, Christopher J PortierAbstract:The two-stage model of carcinogenesis, which incorporates clonal growth of intermediate cells, has gained increasing attention in recent years. It was formulated to match tumor incidence data and expanded to encompass observations made in initiation-promotion carcinogenicity experiments. Mouse skin experiments are perceived as supporting this model, with papillomas representing the intermediate cells and carcinomas representing the malignant cells. In this manuscript, the two-stage model is applied to data concerning papilloma and carcinoma formation from an initiation-promotion NMRI Mouse skin painting experiment which included stop-promotion. It is shown that the model is not compatible with these data if all papillomas are considered premalignant lesions. The model was modified to allow for a heterogeneous population of papillomas. In this case, unless one assumes that premalignant and terminally benign papillomas are morphologically different in the sense that both types of papillomas at detection limit contain distinct numbers of actively dividing initiated cells, the model predicts larger numbers of papillomas at the end of the experiment than were actually observed. The best explanation is that the model is not in accordance with these data and that the data indicate the need for stages between initiated and malignant cells.
Karin Wiench - One of the best experts on this subject based on the ideXlab platform.
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critical evaluation of 2 ethylhexyl acrylate dermal carcinogenicity studies using contemporary criteria
Toxicology Letters, 2018Co-Authors: Sandra Murphy, Robert G Ellishutchings, Lavorgie Finch, Stefanie Welz, Karin WienchAbstract:Skin tumors have been observed in C3H/HeJ mice following treatment with high and strongly irritating concentrations of 2-ethylhexyl acrylate (2-EHA). Dermal carcinogenicity studies performed with 2-EHA are reviewed, contrasting the results in two Mouse strains (C3H/HeJ and NMRI) under different dosing regimens. Application of contemporary evaluation criteria to the existing dermal carcinogenicity dataset demonstrates that 2-EHA induces skin tumors only at concentrations exceeding an maximum tolerated dose (MTD) and in the immune-dysregulated C3H/HeJ Mouse model. Overall, the available chronic toxicity and genotoxicity data on 2-EHA support a non-genotoxic chemical irritant mechanism, whereby chronic irritation leads to inflammation, tissue injury, and wound repair, the latter of which is disrupted in C3H/HeJ mice and leads to tumor formation. Tumor response information in excess of an MTD should not be considered in a human hazard or risk assessment paradigm. For the purposes of an appropriate hazard assessment, 2-EHA did not cause or initiate dermal carcinogenesis in an immune competent (NMRI) Mouse model, and, even in the immune compromised C3H/HeJ model, did not induce skin tumors at doses which did not exceed the MTD.