New Bisabolane-Type Sesquiterpenoids from Curcuma longa and Their Anti-Atherosclerotic Activity

To explore the sesquiterpenoids in Curcuma longa L. and their activity related to anti-atherosclerosis. The chemical compounds of the rhizomes of C. longa were separated and purified by multiple chromatography techniques. Their structures were established by a variety of spectroscopic experiments. The absolute configurations were determined by comparing experimental and calculated NMR chemical shifts and electronic circular dichroism (ECD) spectra. Their anti-inflammatory effects and inhibitory activity against macrophage-derived foam cell formation were evaluated by lipopolysaccharide (LPS) and oxidized low-density lipoprotein (ox-LDL)-injured RAW264.7 macrophages, respectively. This study resulted in the isolation of 10 bisabolane-type sesquiterpenoids (1-10) from C. longa, including two pairs of new epimers (curbisabolanones A-D, 1-4). Compound 4 significantly inhibited LPS-induced nitric oxide (NO), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and prostaglandin E2 (PGE2) production in RAW264.7 cells. Furthermore, compound 4 showed inhibitory activity against macrophage-derived foam cell formation, which was represented by markedly reducing ox-LDL-induced intracellular lipid accumulation as well as total cholesterol (TC), free cholesterol (FC), and cholesterol ester (CE) contents in RAW264.7 cells. These findings suggest that bisabolane-type sesquiterpenoids, one of the main types of components in C. longa, have the potential to alleviate the atherosclerosis process by preventing inflammation and inhibiting macrophage foaming.

Automated summary

This study isolated 10 bisabolane-type sesquiterpenoids from Curcuma longa L., including two pairs of new epimers. One of the compounds significantly inhibited the production of inflammatory mediators and showed inhibitory activity against macrophage-derived foam cell formation. These findings suggest that bisabolane-type sesquiterpenoids have the potential to alleviate the atherosclerosis process by preventing inflammation and inhibiting macrophage foaming.