Glucocorticoid receptor mediates the expansion of splenic late erythroid progenitors during chronic psychological stress.

Stress evokes an integrated neuroendocrine response perturbing the homeostasis of different physiological systems. In contrast to well established physiologica linteractions between neuroendocrine and immune systems during chronic stress, there has been relatively little information on the effects of psychological stress on erythroid cells. Since stress-induced erythropoiesis occurs predominantly in the spleen, in the current study, we investigated the influence of chronic psychological stress on splenic erythroid progenitors and examined a role of glucocorticoid receptor (GR) in observed effect using a mouse model of restraint. The adult male mice were subjected to 2 hours daily restraint stress for 7 or 14 consecutive days and the role of GR in erythropoietic response to stress was assessed by pretreatment of mice with GR antagonist mifepristone 60 min prior to restraint. The results showed that chronic restraint stress induced an increase in spleen weight as well as in the cellularity of red pulp, as compared to controls. Furthermore, 7 and 14 days of restraint stress resulted in markedly increased number of both splenic early (BFU-E) and late (CFU-E) erythroid progenitors. Blockade of GR with mifepristone did not affect the number of BFU-E in stressed mice, but it completely abolished the effect of repeated psychological stress on CFU-E cells. Additionally, plasma corticosterone concentration was enhanced whereas the GR expression was significantly decreased within splenic red pulp after one and two weeks of stress exposure. Obtained findings suggest for the first time an indispensable role for GR in the expansion of CFU-E progenitors in the spleen under conditions of chronic psychological stress.

Mitochondrial DNA sequence and phylogenetic evaluation of geographically disparate Sus scrofa breeds.

Next generation sequencing of mitochondrial DNA (mtDNA) facilitates studies into the metabolic characteristics of production animals and their relation to production traits. Sequence analysis of mtDNA from pure-bred swine with highly disparate production characteristics (Mangalica Blonde, Mangalica Swallow-bellied, Meishan, Turopolje, and Yorkshire) was initiated to evaluate the influence of mtDNA polymorphisms on mitochondrial function. Herein, we report the complete mtDNA sequences of five Sus scrofa breeds and evaluate their position within the phylogeny of domestic swine. Phenotypic traits of Yorkshire, Mangalica Blonde, and Swallow-belly swine are presented to demonstrate their metabolic characteristics. Our data support the division of European and Asian breeds noted previously and confirm European ancestry of Mangalica and Turopolje breeds. Furthermore, mtDNA differences between breeds suggest function-altering changes in proteins involved in oxidative phosphorylation such as ATP synthase 6 (MT-ATP6), cytochrome oxidase I (MT-CO1), cytochrome oxidase III (MT-CO3), and cytochrome b (MT-CYB), supporting the hypothesis that mtDNA polymorphisms contribute to differences in metabolic traits between swine breeds. Our sequence data form the basis for future research into the roles of mtDNA in determining production traits in domestic animals. Additionally, such studies should provide insight into how mtDNA haplotype influences the extreme adiposity observed in Mangalica breeds.

Haematology and blood chemistry changes in mice treated with terbuthylazine and its formulation Radazin TZ-50.

TBA is an herbicide in general low acute toxicity and placed into a third category of toxicity. The aim of this study was to determine the effect of TBA and its formulation Radazin TZ-50 in doses of ADI values and 1/100 LD 50 on haematological and biochemical blood parameters in mice. The number of leukocytes was significantly decreased (p < 0.05) in all treated groups compared to non-treated mice (8.81 ± 3.23 × 10(9)/L). The lowest value 3.90 ± 0.74 × 10(9)/L was observed in group treated with TBA (1/100 LD 50) followed by TBA (ADI) 4.49 ± 0.98 × 10(9)/L, Radazin TZ-50 (1/100 LD 50) 4.67 ± 1.24 × 10(9)/L and Radazin TZ-50 (ADI) 4.73 ± 1.15 × 10(9)/L. The values of the enzyme AST was increased from 190.00 ± 26.46-270.00 ± 147.30 U/L in serum of all treated groups as compared to non-treated mice (110.00 ± 20.00). LDH values showed significant increase (3236.67 ± 56.86-4054.33.5 ± 837.16 U/L) as compared to non-treated mice (1010.00 ± 222.71 U/L). Total protein value was significantly (p < 0.05) increased in TBA 1/100 LD50 (63.00 ± 7.48 g/L) and Radazin TZ-50 1/100 LD50 (60.00 ± 2.00 g/L) compared to non-treated mice 52.00 ± 4.00 g/L. Increased serum concentrations of urea and creatinine obtained in mice treated with TBA and Radazin TZ-50 indicates a greater degree of dysfunction of the nephron. TBA and its formulation of Radazin TZ-50 in applied doses demonstrate changes in the number of leukocytes and limited hepatotoxic effects.

Carbendazim combined with imazalil or cypermethrin potentiate DNA damage in hepatocytes of mice.

Traces of pesticides imazalil, cypermethrin and carbendazim are detected in plants used for human consumption. To explore whether their application in oral combinations will induce DNA breaks in hepatocytes, a subchronic in vivo experiment was performed in Swiss mice. Doses of 10 mg kg(-1) of imazalil (im) and cypermethrin (cy), and 20 mg kg(-1) of carbendazim (car) and their combinations (im, 10 mg kg(-1) + cy, 10 mg kg(-1); im, 10 mg kg(-1) + car, 20 mg kg(-1); car, 20 mg kg(-1) + cy, 10 mg kg(-1)) were applied daily for 28 days. Afterward, DNA damage in hepatocytes was evaluated by comet assay. Individually, imazalil and cypermethrin damaged DNA at alkali-labile sites, while the tail moment (TM) of carbendazim alone was similar to control but with higher tail length. In combination with carbendazim clastogen, properties of imazalils and cypermethrins were potentiated compared to all other treatments and control. There were pronounced sex differences in pattern of fragmentation between treated groups. Higher long tail nuclei (LTN) in females indicate that certain cells in females were especially prone to total nucleus disintegration. Due to synergistic effects, low environmentally present concentrations of imazalil and cypermethrin in food, and especially their mixtures with carbendazim have genotoxic potential that could be particularly dangerous over prolonged exposure in mammalian organism.

DNA damage and repair after exposure to sevoflurane in vivo, evaluated in Swiss albino mice by the alkaline comet assay and micronucleus test.

The relationship between DNA damage and repair of peripheral blood leukocytes, liver, kidney and brain cells was investigated in Swiss albino mice (Mus musculus L.) after exposure to sevoflurane (2.4 vol% for 2 h daily, for 3 days). Genetic damage of mouse cells was investigated by the comet assay and micronucleus test. To perform the comet assay, mice were divided into a control group and 4 groups of exposed mice sacrificed on day 3 of the experiment, at 0, 2, 6 or 24 h after the last exposure to sevoflurane. Mean tail length (TL), tail moment (TM), and tail intensity (TI) values were significantly higher in exposed mice (all examined organs) than in the control group. Significant DNA damage immediately after exposure to sevoflurane was observed in leukocytes. Damage induction in the liver, kidney, and brain occurred 6 h later than in leukocytes, as expected according to the toxicokinetics of the drug, where blood is the first compartment to absorb sevoflurane. However, none of the tested tissues revealed signs of repair until 24 h after the exposure. To distinguish the unrepaired genome damage in vivo, the micronucleus test was applied. Number of micronuclei in reticulocytes showed a statistically significant increase, as compared with the control group at all observed times after the treatment.

The effects of prometryne on subchronically treated mice evaluated by SCGE assay.

Prometryne is a methylthio-s-triazine herbicide used to control annual broadleaf and grass weeds in many cultivated plants. Significant traces are documented in environment, mainly water, soil and plants used for human and domestic animal nutrition. Data on the toxic effects of prometryne and other methylthio-s-triazine have scorcely been published. The goal of this study was to investigate if prometryne, applied orally, could induce DNA damage in mouse leukocytes, in subchronical in vivo experimental design. Three different doses of prometryne were applied per os repeatedly every 48 hours. After the 7th dose (day 14) and the 14th dose (day 28) blood leucocytes were analyzed by alkaline Single Cell Gel Electrophoresis (Comet) assay. The results of three different comet parameters showed general increase in Olive tail moment, tail length and tail intensity values in treated groups of animals. The increase in measured values was almost proportional to the dose received and the time of exposure. We conclude that prometryne or its metabolic residues have the potential to induce processes that cause genotoxic effects on leukocytes on mice in in vivo repeated exposure.

Radioprotective effects of propolis and quercetin in gamma-irradiated mice evaluated by the alkaline comet assay.

The radioprotective effects of ethanolic extract of propolis (EEP) and quercetin on the white blood cells of the whole-body irradiated CBA mice were investigated. Irradiation was performed using a gamma-ray source ((60)Co), and absorbed dose was 9 Gy. The efficiency of test components was evaluated when given intraperitoneally (ip) at a dose of 100 mg kg(-1) for 3 consecutive days before and/or after irradiation. Moreover, possible genotoxic effects of test components were also assessed on non-irradiated animals. For each experimental group leukocyte count was determined and the primary DNA damage in leukocytes was assessed using the alkaline comet assay. The higher efficiency of EEP and quercetin was observed when given preventively. The results suggest that propolis and quercetin given to mice before irradiation protect their white blood cells from lethal effects of irradiation and diminish primary DNA damage as confirmed by the alkaline comet assay. Positive results obtained on gamma-irradiated mice given EEP and quercetin, complementary with our earlier observations on survival of irradiated mice, indicate that these compounds could be considered effective non-toxic radioprotectors. The exact mechanisms of radioprotection by these compounds and their effects on DNA repair processes are still to be elucidated.

Enhanced antitumor activity of irinotecan combined with propolis and its polyphenolic compounds on Ehrlich ascites tumor in mice.

The effects of the anticancer drug irinotecan combined with ethanolic extract of propolis (EEP), a water-soluble derivate of propolis (WSDP), quercetin and naringin on the growth of Ehrlich ascites tumor (EAT) and the life span of tumor-bearing Swiss albino mice were studied. Test components were given to mice intraperitoneally (i.p.) at doses of 100mg kg(-1) for three consecutive days before the i.p. injection of EAT cells (1x10(6)). Irinotecan was administered i.p. at dose of 50mg kg(-1) on days 1, 13, and 19 after tumor cell inoculation. The results clearly demonstrate the synergistic action of irinotecan and EEP on survival time. These results suggest that clinical trials using a propolis preparation EEP combined with irinotecan may be beneficial in maximizing antitumor activity and minimizing post-chemotherapeutic reactions to the cytostatic drug.