Brominated polyunsaturated lipids with protein tyrosine phosphatase-1B inhibitory activity from Chinese marine sponge Xestospongia testudinaria

Abstract

A new brominated polyunsaturated lipid, methyl (E,E)-14,14-dibromo-4,6,13-tetradecatrienoate (1), along with three known related analogues (2–4), were isolated from the Et₂O-soluble portion of the acetone extract of Chinese marine sponge Xestospongia testudinaria treated with diazomethane. The structure of the new compound was elucidated by detailed spectroscopic analysis and by comparison with literature data. Compound 3 exhibited significant inhibitory activity against protein tyrosine phosphatase 1B (PTP1B), a key target for the treatment of type II diabetes and obesity, with an IC₅₀ value of 5.30 ± 0.61 μM, when compared to the positive control oleanolic acid (IC₅₀ = 2.39 ± 0.26 μM).

Keywords::

• brominated polyunsaturated lipid
• sponge
• Xestospongia testudinaria
• PTP1B inhibitory activity

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

^1. These authors contributed to this work equally.

Additional information

Funding

This research work was financially supported by the Natural Science Foundation of China [grant numbers 81273430, 41306130, 81302692 and 41476063], the National Marine ‘863’ Project [grant numbers 2012AA092105 and 2013AA092902], the China Postdoctoral Science Foundation [grant numbers 2012M520956 and 2014T70443], the SKLDR/SIMM Project [grant number 1501ZZ-03], NSFC-Shandong Joint Fund for Marine Science Research Centers [grant number U1406402] and was partially funded by the SCTSM Project [grant number 14431901100].