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941.
Several bacterial and immunogenic factors are involved in the host response to probiotic strains of Lactobacillus. Here, we report the isolation of new intestinal lactobacilli from chicken, with different immunomodulating properties on lymphoid cells from SJL and C57BL/6 mice. Analysis of biochemical markers in the Lactobacillus acidophilus CBA4P, CBA3P, and TPA3P isolates reveal that these bacterial isolates belong to the type 2 prototype, although they differ from each other. The effect of conditioned media (CM) from SJL- and C57BL/6-derived peritoneal macrophages incubated with the 3 sonicated bacterial isolates from chicken, as well as with Lactobacillus rhamnosus 9595, Escherichia coli lipopolysaccharide, or Staphylococcus aureus peptidoglycan were compared. Our results show that the CM of macrophages from C57BL/6 and SJL mice treated with the CBA4P isolate stimulated syngeneic splenic lymphocytes at a level similar to the one induced with CM from peptidoglycan-stimulated macrophages. In contrast, the CM from TPA3P- and CBA3P-treated macrophages promoted low or no stimulation of lymphoid cells. Incubation of splenic cells with CM from macrophages treated with L. rhamnosus or TPA3P led to a relative decrease in the percentages of splenic CD4+ T cells, whereas the relative percentages of B cells increased. The CBA4P and CBA3P isolates induced higher levels of gamma interferon when compared with the TPA3P isolate. The effects of the lactobacilli isolates differed according to the mouse strain used but correlated with the production of macrophagic tumor necrosis factor alpha and interleukins 6, 10, and 12 and with the modulation of the p38 mitogen-activated protein kinase (MAPK). Taken together, these results indicate that the immunomodulating properties of the new L. acidophilus isolates depend on their capacity to induce production of interleukins 10 and 12 by macrophages, which is under genetic control and depends on the p38 MAPK pathway. 相似文献
942.
Statin treatment increases formation of carbon monoxide and bilirubin in mice: a novel mechanism of in vivo antioxidant protection 总被引:1,自引:0,他引:1
Muchova L Wong RJ Hsu M Morioka I Vitek L Zelenka J Schröder H Stevenson DK 《Canadian journal of physiology and pharmacology》2007,85(8):800-810
Heme oxygenase (HO) has a central role in cellular antioxidant defences and vascular protection, and it may mediate pleiotropic actions of drugs used in cardiovascular therapy. We investigated whether long-term use of statins upregulates HO activity and increases carbon monoxide (CO) and bilirubin levels in vivo. Adult FvB mice were given atorvastatin or rosuvastatin (5 mg/kg) daily by i.p. injections for 1, 2, or 3 weeks. HO activity, tissue CO, bilirubin, and antioxidant levels, total plasma bilirubin, and carboxyhemoglobin (COHb) were measured. Fold changes in heart HO activity significantly increased after 1, 2, and 3 weeks of atorvastatin (1.24 +/- 0.06 (p < or = 0.05); 1.29 +/- 0.26 (p < or = 0.03); 1.33 +/- 0.08 (p < 0.01), respectively) and 2 and 3 weeks of rosuvastatin (1.23 +/- 0.20 (p < or = 0.03); 1.63 +/- 0.42 (p < 0.01), respectively). Heart tissue CO and COHb levels also increased after 3 weeks with atorvastatin (1.30 +/- 0.24 (p < or = 0.05); 1.92 +/- 0.17 (p < or = 0.001), respectively) and rosuvastatin (1.47 +/- 0.13 (p < or = 0.004); 1.63 +/- 0.12 (p < or = 0.001), respectively). Significant increases in heart antioxidant levels were observed after statin treatment and corroborated by heart bilirubin content elevations. Antioxidant level increases were abolished by treatment with an HO inhibitor. These findings suggest that the induction of HO and the production of its products, CO and bilirubin, may be a mechanism by which statins exert antioxidant actions and confer cardioprotection in vivo. 相似文献
943.
Clere N Bermont L Fauconnet S Lascombe I Saunier M Vettoretti L Plissonnier ML Mougin C 《Experimental cell research》2007,313(15):3239-3250
944.
945.
Rousseaux C Thuru X Gelot A Barnich N Neut C Dubuquoy L Dubuquoy C Merour E Geboes K Chamaillard M Ouwehand A Leyer G Carcano D Colombel JF Ardid D Desreumaux P 《Nature medicine》2007,13(1):35-37
Abdominal pain is common in the general population and, in patients with irritable bowel syndrome, is attributed to visceral hypersensitivity. We found that oral administration of specific Lactobacillus strains induced the expression of mu-opioid and cannabinoid receptors in intestinal epithelial cells, and mediated analgesic functions in the gut-similar to the effects of morphine. These results suggest that the microbiology of the intestinal tract influences our visceral perception, and suggest new approaches for the treatment of abdominal pain and irritable bowel syndrome. 相似文献
946.
Addis Samantha D. Formel Stephen K. Kim Yeon Ji Varner Paige B. Raudabaugh Daniel B. Lefevre Emilie Bernik Brittany M. Elango Vijaikrishnah Van Bael Sunshine A. Pardue John H. Gunsch Claudia K. 《Biodegradation》2022,33(1):87-98
Biodegradation - The 2010 Deepwater Horizon disaster remains one of the largest oil spills in history. This event caused significant damage to coastal ecosystems, the full extent of which has yet... 相似文献
947.
BioMetals - The aim of this article is to study the impact of both copper (Cu2+) and arsenic (As (V)) at 100 µg/L, with each element being combined with trophic conditions at the... 相似文献
948.
Ximena M. Bustamante-Marin Wei-Ning Yin Patrick R. Sears Michael E. Werner Eva J. Brotslaw Brian J. Mitchell Corey M. Jania Kirby L. Zeman Troy D. Rogers Laura E. Herring Luc Refabért Lucie Thomas Serge Amselem Estelle Escudier Marie Legendre Barbara R. Grubb Michael R. Knowles Maimoona A. Zariwala Lawrence E. Ostrowski 《American journal of human genetics》2019,104(2):229-245
949.
950.
Lucie Marhounov Alexander Kotrschal Kristina Kverkov Niclas Kolm Pavel Nmec 《Evolution; international journal of organic evolution》2019,73(9):2003-2012
Neurons are the basic computational units of the brain, but brain size is the predominant surrogate measure of brain functional capacity in comparative and cognitive neuroscience. This approach is based on the assumption that larger brains harbor higher numbers of neurons and their connections, and therefore have a higher information‐processing capacity. However, recent studies have shown that brain mass may be less strongly correlated with neuron counts than previously thought. Till now, no experimental test has been conducted to examine the relationship between evolutionary changes in brain size and the number of brain neurons. Here, we provide such a test by comparing neuron number in artificial selection lines of female guppies (Poecilia reticulata) with >15% difference in relative brain mass and numerous previously demonstrated cognitive differences. Using the isotropic fractionator, we demonstrate that large‐brained females have a higher overall number of neurons than small‐brained females, but similar neuronal densities. Importantly, this difference holds also for the telencephalon, a key region for cognition. Our study provides the first direct experimental evidence that selection for brain mass leads to matching changes in number of neurons and shows that brain size evolution is intimately linked to the evolution of neuron number and cognition. 相似文献