title: Petrosaspongiolides M-R: new potent and selective phospholipase A2 inhibitors from the New Caledonian marine sponge Petrosaspongia nigra.
abstract: Five new bioactive sesterterpenes (1-5) have been isolated from the New Caledonian marine sponge Petrosaspongia nigra Bergquist and named petrosaspongiolides M-R. Their chemical structures were determined from 1D and 2D NMR studies and MS data. All compounds inhibited different preparations of phospholipase A2 (PLA2) by irreversibly blocking these enzymes (particularly human synovial and bee venom, see Table 3), with IC50 values in the micromolar range. Interestingly, these compounds displayed a much lower activity (or no activity at all) toward porcine pancreas and Naja naja venom PLA2 enzymes. The most potent compound, 1 (IC50 1.6 and 0.6 microM for human synovial and bee venom PLA2 enzymes, respectively), was slightly more active than manoalide (6) (IC50 3.9 and 7.5 microM) under our experimental conditions. Compound 3 is more selective, inhibiting human synovial PLA2 to a greater extent than bee venom PLA2.
authors.affiliation: Dipartimento di Chimica delle Sostanze Naturali, Università degli Studi di Napoli "Federico II", via D. Montesano 49, 80131 Napoli, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Randazzo
authors.forename: C
authors.initials: C
authors.lastname: Debitus
authors.forename: L
authors.initials: L
authors.lastname: Minale
authors.forename: P
authors.initials: P
authors.lastname: García Pastor
authors.forename: M J
authors.initials: MJ
authors.lastname: Alcaraz
authors.forename: M
authors.initials: M
authors.lastname: Payá
authors.forename: L
authors.initials: L
authors.lastname: Gomez-Paloma
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000818:Animals; D001514:Bee Venoms / Q000201:enzymology; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010179:Pancreas / Q000201:enzymology; D010741:Phospholipases A / Q000037:antagonists & inhibitors*; D054467:Phospholipases A2; D011161:Porifera / Q000737:chemistry*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013552:Swine; D013582:Synovial Fluid / Q000201:enzymology; D013729:Terpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D001514:Bee Venoms; D004791:Enzyme Inhibitors; D013729:Terpenes; D010741:Phospholipases A; D054467:Phospholipases A2; D015107:4-Butyrolactone