Secondary Metabolites from Three Florida Sponges with Antidepressant Activity

Abstract

Brominated indole alkaloids are a common class of metabolites reported from sponges of the order Verongida. Herein we report the isolation, structure determination, and activity of metabolites from three Florida sponges, namely, Verongula rigida (order Verongida, family Aplysinidae), Smenospongia aurea, and S. cerebriformis (order Dictyoceratida, family Thorectidae). All three species were investigated chemically, revealing similarities in secondary metabolites. Brominated compounds, as well as sesquiterpene quinones and hydroquinones, were identified from both V. rigida and S. aurea despite their apparent taxonomic differences at the ordinal level. Similar metabolites found in these distinct sponge species of two different genera provide evidence for a microbial origin of the metabolites. Isolated compounds were evaluated in the Porsolt forced swim test (FST) and the chick anxiety-depression continuum model. Among the isolated compounds, 5,6-dibromo- N,N-dimethyltryptamine ( 1) exhibited significant antidepressant-like action in the rodent FST model, while 5-bromo- N,N-dimethyltryptamine ( 2) caused significant reduction of locomotor activity indicative of a potential sedative action. The current study provides ample evidence that marine natural products with the diversity of brominated marine alkaloids will provide potential leads for antidepressant and anxiolytic drugs.

Epi-Leptosphaerin: A New L-Isoascorbic Acid Derivative from Marine Sponges

“…The ethanol extracts of the three sponges, V. rigida, S. aurea and S. cerebriformis, 8,9 led to the isolation of a new epi-leptosphaerin (1) as well as known leptosphaerin (2) and verongamine (3). These isolated compounds were subsequently evaluated in terms of their sEH inhibition.…”

“…In our ongoing mission to isolate bioactive metabolites from marine sponges of the orders Verongida and Thorectidae, our earlier studies have demonstrated the antidepressant and cytotoxic activities of numerous compounds and have isolated uncommon metabolites. [8][9][10][11] A survey of the literature reveals that bromotyrosine-types of compounds are the mainstay of the Verongida chemical repertoire. One structural feature that is common to each of these is an amide bond that confers sEH inhibitory activity.…”

“…8,9 Dried ethanol extract (3.6 kg) was subjected to silica-gel vacuum liquid chromatography (VLC) using a stepwise gradient of hexane/acetone/methanol/water to give 13 fractions (Fr. 1-13).…”

Aplysfistularine: a novel dibromotyrosine derivative isolated from Aplysina fistularis

“…[11][12][13][14][15] Sponges of the order Verongida, and the family Aplysinidae, characterized by the absence of terpenes and the production of steroids, produce a wide diversity of bromotyrosine-containing metabolites with interesting biological properties. 16 The richest sources of biogenetically, tyrosine--derived bromo-containing amines, are members of the Verongida order, and the genus Aplysina. [17][18][19][20] Previous and recent reports of Aplysina fistularis have documented the presence of a large number of brominated metabolites including: fistularines, aerothionines, ceratinamines, aplysamines, anamonianes and psammaplysines.…”

A novel natural phenyl alkene with cytotoxic activity

“…1 While investigation of secondary metabolites from marine sponges Smenospongia (order Dictyoceratida, family Thorectidae) and Verongula (order Verongida, family Aplysinidae) has received great attention, only a few chemical groups that belong to alkaloids and terpenoids have been isolated from these marine invertebrates. 2,3 Of these, sesquiterpene quinones and hydroquinones are the best known classes of secondary metabolites, accounting for more than 170 compounds published from these sponges. 4 Our previous study on the isolation of antidepressant compounds from three Florida sponges, Verongula rigida (Esper, 1794), Smenospongia aurea (Hyatt, 1875), and Smenospongia cerebriformis (Duchassaing and Michelotti, 1864), 3c showed that the same brominated alkaloids, as well as sesquiterpene quinones and hydroquinones, were found in both V. rigida and S. aurea despite their apparent taxonomic differences.…”