Cell cytotoxity and anti-glycation activity of taxifolin-rich extract from Japanese larch, Larix kaempferi

Abstract

The larches, the Larix genus of plants are known as a natural source of taxifolin (dihydroquercetin), and extracts of its taxifolin rich xylem are used in dietary supplements to maintain health. In the present study, to assess biological activities of a methanol extract of the Japanese larch, Larix kaempferi (LK-ME), the effects of LK-ME on cell viability, inflammatory cytokine expression, and glycation were investigated. The effects of taxifolin which is known to be a main compound of LK-ME, and its related flavonoids, quercetin and luteolin were also examined. The results show that taxifolin exhibits lower growth inhibition activity and lesser induction activity of inflammatory cytokines in a human monocyte derived cell line, THP-1 cells, while in vitro anti-glycation activities of taxifolin were inhibiting at comparable levels to those of quercetin and luteolin. The growth inhibition and the cytokine induction activities, and the anti-glycation effects of LK-ME are assumed to have properties similar to taxifolin. The results of high performance liquid chromatography (HPLC) analysis indicated that taxifolin was detected as the main peak of LK-ME at the absorbance of 280 nm, and the concentration of taxifolin was measured as 3.12 mg/ml. The actual concentration of taxifolin in LK-ME is lower than the concentration estimated from the IC 50 values calculated by the results of glycation assays, suggesting that other compounds contained in LK-ME are involved in the anti-glycation activity.

In vitro anti-inflammatory and anti-lipid accumulation properties of taxifolin-rich extract from the Japanese larch, Larix kaempferi

“…These lower induction activities of quercetin and luteolin on the expressions of LXRβ and ABCG1 mRNAs are thought to be involved in cell cytotoxicity. Our previous study demonstrated that cell cytotoxicity of taxifolin is significantly lower than that of quercetin and luteolin in undifferentiated (monocyte like) THP-1 cells [ 16 ]. As shown in Figure 6 , taxifolin cytotoxicity is also weaker in quercetin and luteolin in macrophage differentiated THP-1 cells.…”

“…Previously, we have demonstrated that the L. kaempferi methanol extract (LK-ME) exhibits anti-glycation activity [ 16 ]. High performance liquid chromatography (HPLC) analysis has indicated that taxifolin is the main compound in LK-ME, and most of the flavonoids contained in LK-ME are assumed to be taxifolin.…”

Green and Sustainable Valorization of Bioactive Phenolic Compounds from Pinus By-Products

“…nigra bark [ 120 ] with a maximum extraction recovery of 34%. Taxifolin was detected as the major compound in other needle leaved trees such as the Japanese larch, Larix kaempferi [ 175 ]. Its main bioactivities are antioxidant, anticancer, and anti-inflammatory [ 148 , 167 ].…”

The effect of Kappaphycus alvarezii fraction on plasma glucose, Advanced Glycation End-products formation, and renal RAGE gene expression

“…The two extracts were then monitored by the bioassay (BSA-Glucose) method and the chromatography pattern was also observed. In the BSA-Glucose method, the glycation inhibition process can be seen from the formation of fluorescent glycated protein ( Muramatsu et al., 2019 ). This bioassay-guided fractionation method has been previously applied to detect the presence of active fractions from T. diversifolia (Hemsley) A.…”