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PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1995-11-9
pubmed:abstractText
We previously reported that difluoromethylornithine (DFMO), an inhibitor of polyamine biosynthesis, exerted significant beneficial effects on the lifespan and disease expression of MRL-lpr/lpr mice, which spontaneously develop a lupus-like syndrome. Polyamine levels in splenic T-cells of MRL-lpr/lpr mice were significantly higher than those of Balb/c mice. In the present investigation, we examined the role of endogenous polyamines in transmembrane Ca2+ influx, generation of InsP3 and tyrosine phosphorylation of the p56lck protein in concanavalin A-stimulated splenic T-cells. Cytosolic free calcium concentrations ([Ca2+]i) in concanavalin A-stimulated T-cells of MRL-lpr/lpr and Balb/c mice were 250 +/- 25 and 450 +/- 42 nM respectively. Treatment of MRL-lpr/lpr mice with DFMO increased [Ca2+]i to 360 +/- 30 nM (P < 0.05). InsP3 levels of concanavalin A-stimulated MRL-lpr/lpr splenic T-cells were only 20% higher than those of unstimulated controls, whereas those of Balb/c T-cells were 90% higher. DFMO treatment increased InsP3 levels in concanavalin A-treated MRL-lpr/lpr T-cells to 67%. Western-blot analysis showed a 7-fold higher level of p56lck phosphorylation of MRL-lpr/lpr splenic T-cells than that of Balb/c mice. DFMO treatment reduced tyrosine phosphorylation of p56lck of MRL-lpr/lpr mice significantly (P < 0.001). Two-colour flow-cytometric analysis revealed no significant difference in the CD4+/CD8+ ratio in splenic T-cells of MRL-lpr/lpr mice after DFMO treatment. Polyamine levels in splenocytes were significantly reduced by DFMO treatment. These data show that DFMO treatment could alter signal-transduction pathways of splenic T-cells of MRL-lpr/lpr mice. Increased levels of polyamines in T-cells of untreated lpr mice contribute to defective signal-transduction pathways and the pathogenesis of lupus-like symptoms.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-12412756, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1356108, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1372394, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1385243, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1397089, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1458466, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1459994, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1472637, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1532002, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1551114, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1579166, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1832077, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-1976707, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2023214, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2067204, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2107025, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2187296, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2188673, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2424993, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2432431, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2434867, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2500353, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2505811, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2548204, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2784801, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2786526, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2787933, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2831196, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-2851975, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-3087344, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-3119327, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-3374260, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-3497786, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-3722208, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-3905315, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-393470, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-6097190, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-6206782, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-6456321, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-7150264, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-7391583, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-7578852, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-7682246, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-7688023, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-7756170, http://linkedlifedata.com/resource/pubmed/commentcorrection/7575451-8097908
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0264-6021
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
311 ( Pt 1)
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
175-82
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
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