Zoanthamine-Type Alkaloids from the Zoanthid Zoanthus kuroshio Collected in Taiwan and Their Effects on Inflammation

Abstract

Zoanthus kuroshio is a colorful zoanthid with a fluorescent pink oral disc and brown tentacles, which dominates certain parts of the Taiwanese and Japanese coasts. This sea anemone is a rich source of biologically active alkaloids. In the current investigation, two novel halogenated zoanthamines [5α-iodozoanthenamine (1) and 11β-chloro-11-deoxykuroshine A (2)], along with four new zoanthamines [18-epi-kuroshine A (3), 7α-hydroxykuroshine E (4), 5α-methoxykuroshine E (5), and 18-epi-kuroshine E (6)], and six known compounds were isolated from Z. kuroshio. Compounds 1 and 2 are the first examples of halogenated zoanthamine-type alkaloids isolated from nature. Compounds 3 and 6 are the first zoanthamine stereoisomers with a cis-junction of the A/B rings. All isolated compounds were evaluated for their anti-inflammatory activities by measuring their effects on superoxide anion generation and elastase release by human neutrophils in response to fMLP.

Marine Alkaloids with Anti-Inflammatory Activity: Current Knowledge and Future Perspectives

“…Aqueous extracts from the anemones Anemonia sulcata and Actinia equina, whose major detected constituent was the methylpiridinium alkaloid homarine (31), were able to reduce NO and reactive oxygen species (ROS) production in LPS-stimulated RAW 264.7 cells and had an inhibitory effect on the activity of PLA 2 , one of the enzymes involved in the activation of the arachidonic acid pathway during the inflammatory response [87]. The compound 5α-iodozoanthenamine (32), a zoanthamine alkaloid from the cnidarian Zoanthus kuroshio, showed an anti-inflammatory effect on fMLP-stimulated neutrophils, reducing superoxide anion generation and elastase release by these cells [88]. The molecules 3-hydroxinorzoanthamine (33), norzoanthamine (34), and zoanthamine (35), additional zoanthamine alkaloids extracted from Zoanthus cf.…”

Anti-Lymphangiogenesis Components from Zoanthid Palythoa tuberculosa

“…Accordingly, zoanthids are also regarded as rich sources of novel secondary metabolites with diverse bioactivities. For example, ecdysones isolated from Palythoa mutuki suppressed dengue virus production [ 4 ], while alkaloids purified from Zoanthus kuroshio inhibited superoxide anion generation and elastase release [ 5 ]. Compared to octocorals, the natural product investigation of zoanthids is relatively rare and we believe this type of marine invertebrate is a worthy research material.…”

Zoanthamine Alkaloids from the Zoantharian <em>Zoanthus </em>cf<em>. pulchellus</em> and Their Effect in Neuroinflammation

“…The first alkaloid of this group was isolated in 1984 from an unidentified species of Zoanthus, collected off the coast of India by Faulkner and co-workers [1]. Following [4], zoaramine [5], kuroshines [6], epioxyzoanthamine [7], zoanthenol [8], some hydroxylated zoanthamines and norzoanthamines [9] and two halogenated zoanthamines [10]. This interesting family of alkaloids has been structurally classified in two different groups based on the presence of a methyl at C-19 (Type I) or without the methyl (Type II) also called norzoanthamine [10].…”

“…Following [4], zoaramine [5], kuroshines [6], epioxyzoanthamine [7], zoanthenol [8], some hydroxylated zoanthamines and norzoanthamines [9] and two halogenated zoanthamines [10]. This interesting family of alkaloids has been structurally classified in two different groups based on the presence of a methyl at C-19 (Type I) or without the methyl (Type II) also called norzoanthamine [10]. Due to the structural complexity of these natural products, the first total synthesis of norzoanthamine was accomplished by Miyashita et al, later in 2004.…”

“…In the presence of this family of compounds, NO release was significantly inhibited. The anti-inflammatory effect of zoanthamines was previously approached in neutrophils[10].From our results in the BV-2 cellular model, zoanthamine and derivatives show effective properties as protective drugs in neuroinflammation processes Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 3 July 2018 doi:10.20944/preprints201807.0046.v1 Peer-reviewed version available at Mar. Drugs 2018, 16, 242; doi:10.3390/md16070242 Effects of the five zoanthamine derivatives isolated from Z. cf.…”