Screening and Identification of an Anti-inflammatory and Anti-adipogenic Constituent from Ligularia taquetii Nakai

Ligularia taquetii (H. Lev. & Vaniot) Nakai has traditionally been used to treat inflammation and skin swelling in the Jeju Island, Korea. The objective of this study was to investigate the anti-inflammatory and anti-adipogenic effects of Ligularia taquetii ethanoic extract (LTE), in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and 3T3-L1 adipocytes. Lipopolysaccharide-induced inflammation was reduced by LTE in a concentration-dependent manner, via the nuclear factor-κB signaling pathway. Ligularia taquetii ethanoic extract (100 µg/mL) inhibited the LPS-induced production of nitric oxide (NO) and inducible nitric oxide synthase (iNOS), by 60% and 100%, respectively. In comparison, 200 and 100 µg/mL LTE suppressed the LPS-stimulated production of prostaglandin-2 (PGE 2 ) and cyclooxygenase-2 by 50% and 80%, respectively. Ligularia taquetii ethanoic extract also inhibited the secretion of interleukin-1β and interleukin-6 at 300 and 100 μg/mL by 15% and 30%, respectively. High-performance liquid chromatography-photodiode array analysis, combined with mass analysis, revealed chlorogenic acid (CGA) as the anti-inflammatory constituent of LTE. Conversely, 25, 50, 100, and 200 μg/mL LTE lowered the lipid accumulation by 6%, 8%, 25%, and 60%, respectively, while simultaneously increasing cell viability by 7%, 14%, 34%, and 78%. The anti-adipogenic effect of LTE at 100 µg/mL was equivalent to that of CGA at 50 µg/mL. However, LTE treatment promoted cell proliferation by about 30% compared to its CGA-treated counterpart. These results suggest the potential of LTE as a new resource in the discovery of anti-inflammatory and anti-obesity drugs.