An Asp49 Phospholipase A2 from Snake Venom Induces Cyclooxygenase-2 Expression and Prostaglandin E2 Production via Activation of NF-κB, p38MAPK, and PKC in Macrophages
Figure 4
Effect of inhibition of p38MAPK, PI3K, and PKC on COX-2 expression, PGE2 production, and NF-B activation induced by MT-III. Resident peritoneal macrophages ( cells) were pretreated with either SB202190 (1 M), Ly294002 (25 M), or H7-dihydro (20 M) and incubated during 4.5 h with MT-III (0.4 M). In electrophoretic mobility shift assay (EMSA), resident macrophages ( cells) were pretreated with kinases inhibitors and incubated during 30 min with MT-III (a) Western blotting of COX-2 and -actin (loading control). (b) Densitometric analysis of immunoreactive COX-2 band intensities. (c) PGE2 was quantified in culture supernatants by enzyme immunoassays (see Section 2). (d) Nuclear extracts were prepared and assayed for B probe activity with 32P-labeled double-stranded oligonucleotide B using EMSA. (f) Densitometric analysis of NF-B band intensities. Results are expressed as mean ± SEM from 3 experiments. * as compared with control values. NS: nonspecific band; C: control.
