Structural Moieties Required for Cinnamaldehyde-Related Compounds to Inhibit Canonical IL-1ß Secretion.

Suppressing canonical NOD-like receptor protein 3 (NLRP3) inflammasome-mediated interleukin (IL)-1ß secretion is a reliable strategy for the development of nutraceutical to prevent chronic inflammatory diseases. This study aimed to find out the functional group responsible for the inhibitory effects of cinnamaldehyde-related compounds on the canonical IL-1ß secretion. To address this, the suppressing capacities of six cinnamaldehyde-related compounds were evaluated and compared by using the lipopolysaccharide (LPS)-primed and adenosine 5'-triphosphate (ATP)-activated macrophages. At concentrations of 25~100 µM, cinnamaldehyde and 2-methoxy cinnamaldehyde dose-dependently inhibited IL-1ß secretion. In contrast, cinnamic acid, cinnamyl acetate, cinnamyl alcohol and α-methyl cinnamaldehyde did not exert any inhibition. Furthermore, cinnamaldehyde and 2-methoxy cinnamaldehyde diminished expressions of NLRP3 and pro-IL-1ß. Meanwhile, cinnamaldehyde and 2-methoxy cinnamaldehyde prevented the ATP-induced reduction of cytosolic pro-caspase-1 and increase of secreted caspase-1. In conclusion, for cinnamaldehyde-related compounds to suppress NLRP3 inflammasome-mediated IL-1ß secretion, the propenal group of the side chain was essential, while the substituted group of the aromatic ring played a modifying role. Cinnamaldehyde and 2-methoxy cinnamaldehyde exerted dual abilities to inhibit canonical IL-1ß secretion at both stages of priming and activation. Therefore, there might be potential to serve as complementary supplements for the prevention of chronic inflammatory diseases.

Anti-neuroinflammatory capacity of fresh ginger is attributed mainly to 10-gingerol.

Despite the anti-neuroinflammatory capacity of ginger, the corresponding active constituents are unclear. This study analyzed the composition of fresh ginger ethanolic extract by using LC-MS. Inhibitory activities of fresh ginger extract and seven gingerol-related compounds on the neuro-inflammation were also evaluated by using a lipopolysaccharide (LPS)-activated BV2 microglia culture model. Except for zingerone and 6-gingerol, other gingerols and shogaols at a concentration of 20 µM inhibited the production of nitric oxide, IL-1ß, IL-6 and TNF-α as well as their mRNA levels in LPS-activated BV2 microglia. Blocking NF-κB activation was the underlying mechanism responsible for inhibiting the proinflammatory gene expression. Increasing the alkyl chain length enhanced the anti-neuroinflammatory capacity of gingerols yet, conversely, attenuated those of shogaols. 6-Gingerol was the most abundant compound in the fresh ginger extract, followed by 10-gingerol. Furthermore, fresh ginger extract exhibited a significant anti-neuroinflammatory capacity, which was largely owing to 10-gingerol, but not 6-gingerol.

Inhibition of neuroinflammation by cinnamon and its main components.

Uncontrolled activation of microglia contributes to neuroinflammation, which is highly involved in the development of neurodegenerative diseases. Although cinnamon has neuro-protective properties, its capacity to inhibit neuroinflammation has not been investigated and its active compounds remain unclear. Therefore, the composition of cinnamon extract was analysed by LC-MS and the ability of cinnamon and its main constituents to inhibit neuroinflammation was evaluated using a lipopolysaccharide (LPS)-activated BV2 microglia culture system. In total, 50 µg/mL cinnamon extract decreased significantly the production and expression of nitric oxide (NO), interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α in LPS-activated BV2 microglia. Blocking of nuclear factor-κB (NF-κB) activation was the most likely mechanism responsible for inhibition by cinnamon of neuroinflammation. Among the eight tested compounds, cinnamaldehyde had the greatest anti-neuroinflammatory capacity. Experimental results suggest that cinnamon may have a potential therapeutic effect against neurodegenerative diseases and its potent anti-neuroinflammatory capacity was primarily attributed to cinnamaldehyde.

Hairy root cultures of Gynostemma pentaphyllum (Thunb.) Makino: a promising approach for the production of gypenosides as an alternative of ginseng saponins.

Hairy root cultures of Gynostemma pentaphyllum were established by infecting leaf discs with Agrobacterium rhizogenes. The dry biomass of hairy roots grown in MS medium for 49 days was 7.3 g l(-1) with a gypenoside content of 38 mg g(-1) dry wt.