Journal of Functional Foods (Aug 2021)
Sesquiterpenoids from the rhizomes of Atractylodes macrocephala and their protection against lipopolysaccharide-induced neuroinflammation in microglia BV-2 cells
Abstract
The rhizomes of Atractylodes macrocephala have been widely used in both functional foods and herbal medicines for a long history. A phytochemical investigation of its 95% ethanol extract offered twenty-three sesquiterpenoids, including eight new ones named (4S,5S)-atractylmacrene A (1a), atractylmacrenes B–C (2–3), 4R,5R,8S,9S-diepoxylatractylenolide Ⅱ (4), 4-oxo-8S,9S-epoxylatractylenolide Ⅱ (5), and 8S,9S-epoxylatractylenolide Ⅱ (6), among which three pairs of enantiomers (1a/1b, 2a/2b, and 3a/3b) were successfully isolated by the chiral-phase HPLC resolution. Their structures were elucidated using NMR and HRESIMS analyses, electronic circular dichroism (ECD) and X-ray diffraction analyses. Neuroprotective activity in LPS induced BV-2 microglia cells were performed, and compounds 4 and 6 showed significant NO inhibition with IC50 values of 15.8, and 17.8 μΜ, respectively. Mechanism study showed that 4 exerted its protective effect through inhibiting the production of interleukin-6 (IL-6). The findings disclosed the potential of A. macrocephala to be developed as new neuroprotective functional food and medicine.