abortus LPS To test whether viable bacteria were necessary to induce MMP from astrocytes, the ability of heat killed B. abor tus to induce the secretion of MMP 9 was ex amined. PMA was used as control. selleck compound The secretion of MMP 9 was markedly enhanced in culture supernatants from astrocytes stimulated with HKBA when compared with the unstimulated cells, as assessed by zymography and gelatinolytic activity test. MMP 9 production was a function of the amount of bacteria present in the culture. A significant MMP 9 activity was detected in cultures containing be tween 1 �� 106 and 1 �� 109 bacteria ml, a similar bacterial concentration that Inhibitors,Modulators,Libraries the one able to elicit the secretion of MMP 9 with live bacteria. These results suggest that the secretion of MMP 9 could be induced by a structural component of B.

abortus. Since we have previously dem onstrated that B. abortus lipoproteins induce cytokine and MMP secretion in different cells types, we hypothesized that lipoproteins could also Inhibitors,Modulators,Libraries mediate such ef fects in astrocytes. To investigate this hypothesis we used recombinant L Omp19 as a Brucella lipoprotein model. Astrocytes were incubated with L Omp19 and cul ture supernatants were Inhibitors,Modulators,Libraries harvested 48 hours later to meas ure the secretion of MMP 9 by zymography, ELISA and gelatinolytic activity test. L Omp19 induced a significant secretion of MMP 9 in a dose dependent fashion. Independently of the way in which MMP 9 activity was evaluated, its induction was dependent on the lipidation of L Omp19, as U Omp19 failed to induce the secretion of MMP 9. To ascertain whether the effects elicited by L Omp19 could be extended to all B.

abortus lipoproteins, the production of MMP 9 was also evaluated in astrocytes in Inhibitors,Modulators,Libraries cubated with a synthetic lipohexapeptide that mimics the structure of the lipoprotein lipid moiety. Pam3Cys also stimulated MMP 9 secretion by astrocytes. These results indicate that the Pam3 modified cysteine is the Inhibitors,Modulators,Libraries molecular structure of L Omp19 that induces MMP 9 secretion. At variance with the results obtained with L Omp19, B. abortus LPS did not induce MMP 9 production even when used at high doses. Altogether, these results indicate that B. abortus lipoproteins induce the secretion of MMP 9 in astrocytes. HKBA and L Omp19 induce phosphorylation of p38 and Erk1 2, but not Jnk1 2 in astrocytes MAPK play a key role in the regulation of pro inflammatory cytokines and MMP production.

Thus, we explored selleck chemical the possibility that MAPK could play a role in mediating MMP 9 secretion, as induced by B. abortus lipoproteins. As a first step, we investigated whether p38 and Erk1 2 MAPK were phosphorylated in astrocytes when these cells were treated with HKBA or L Omp19. PMA stimulation was used as a positive con trol. Both, HKBA and L Omp19 induced p38 and Erk1 2 phosphorylation in a dose dependent fashion. L Omp19 induced phosphorylation depended upon the lipidation of L Omp19, as U Omp19 failed to induce the activation of both p38 and Erk1 2 MAPK.