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Jean L. Cadet S. F. Ali Richard B. Rothman Charles J. Epstein 《Molecular neurobiology》1995,11(1-3):155-163
Administration of methamphetamine (METH) to animals causes loss of DA terminals in the brain. The manner by which METH causes these changes in neurotoxicity is not known. We have tested the effects of this drug in copper/zinc (CuZn)-superoxide dismutase transgenic (SOD Tg) mice, which express the human CuZnSOD gene. In nontransgenic (non-Tg) mice, acute METH administration causes significant decreases in DA and dihydroxyphenylacetic acid (DOPAC) in the striata of non-Tg mice. In contrast, there were no significant decreases in striatal DA in the SOD Tg mice. The effects of METH on DOPAC were also attenuated in SOD Tg mice. Chronic METH administration caused decreases in striatal DA and DOPAC in the non-Tg mice, but not in the SOD-Tg mice. Similar studies were carried out with 1-methyl-1,2,3,6-tetrahydropyridine (MPTP), which also causes striatal DA and DOPAC depletion. As in the case of METH, MPTP causes marked depletion of DA and DOPAC in the non-Tg mice, but not in the SOD Tg mice. These results suggest that the mechanisms of toxicity of both METH and MPTP involve superoxide radical formation. 相似文献
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Mariarosaria Bucci Anna Cantalupo Valentina Vellecco Elisabetta Panza Maria Chiara Monti Angela Zampella Angela Ianaro Giuseppe Cirino 《PloS one》2013,8(3)
Here we have characterized perthamide C, a cyclopeptide from a Solomon Lithistid sponge Theonella swinhoei, which displays an anti-inflammatory/immunomodulatory activity. The study has been performed using the carragenan-induced mouse paw edema that displays an early (0–6 h) and a late phase (24–96 h). Perthamide C significantly inhibits neutrophils infiltration in tissue both in the early and late phases. This effect was coupled to a reduced expression of the endothelial nitric oxide synthase (eNOS) in the early phase while cyclooxygenase-1 and 2 (COX-1, COX-2), and inducible NOS (iNOS) expression were unaffected. In the late phase perthamide C reduced expression of both NOS isoforms without affecting COXs expression. This peculiar selectivity toward the two enzymes deputed to produce NO lead us to investigate on a possible action of perthamide C on lymphocytes infiltration and activation. We found that perthamide C inhibited the proliferation of peripheral lymphocytes, and that this effect was secondary to its metabolic activation in vivo. Indeed, in vitro perthamide C did not inhibit proliferation as opposite to its metabolite perthamide H.In conclusion, perthamide C selectively interferes with NO generation triggered by either eNOS or iNOS without affecting either COX-1 or COX-2. This in turn leads to modulation of the inflammatory response through a reduction of vascular permeability, neutrophil infiltration as well as lymphocyte proliferation. 相似文献
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Bertero Valentina Goytia Beznec A. Faccio P. Auteri M. Arteaga M. Bonafede M. Bossio E. 《In vitro cellular & developmental biology. Plant》2020,56(6):915-919
In Vitro Cellular & Developmental Biology - Plant - In vitro culture has been recognized as a potential plant clonal propagation tool for a broad variety of commercial, ornamental, and... 相似文献
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Ratajczak Mariusz Z. Adamiak Mateusz Bujko Kamila Thapa Arjun Pensato Valentina Kucia Magda Ratajczak Janina Ulrich Henning 《Purinergic signalling》2020,16(2):153-166
Purinergic Signalling - Bone marrow (BM) as an active hematopoietic organ is highly sensitive to changes in body microenvironments and responds to external physical stimuli from the surrounding... 相似文献