Soluble epoxide hydrolase inhibitory activity of anthraquinone components from Aloe

Aloe is a short-stemmed succulent herb widely used in traditional medicine to treat various diseases and as raw material in cosmetics and heath foods [1, 2]. In this study, we isolated and identified two new anthraquinone derivatives, aloinoside C (6) and aloinoside D (7), together with six known compounds from an aqueous dissolved Aloe exudate. Their structures were identified by spectroscopic analysis [2 – 5]. The inhibitory effects of the isolated compounds on soluble epoxide hydrolase (sEH) were evaluated [3, 4]. Compounds 1-8 inhibited sEH activity potently, with IC₅₀ values ranging from 4.1 ± 0.6 to 41.1 ± 4.2µM. A kinetic analysis of compounds 1-8 revealed that the inhibitory actions of compounds 1, 6 and 8 were non-competitive, whereas those of compounds 2-5 and 7 were the mixed-type. Molecular docking increases our understanding of receptor-ligand binding of all compounds. The Autodock scores for 1-8 were -7.26, -6.92, -7.81, -7.38, -7.38, -8.51, -7.71, and -8.59 kcal/mol, respectively. These results demonstrate that compounds 1-8 from Aloe are potential sEH inhibitors.

Keywords: Aloe, anthraquinone derivatives, soluble epoxide hydrolase (sEH), molecular simulation.

References:

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No conflict of interest has been declared by the author(s).