Verification of anti-inflammatory activity of Juglans mandshurica Maxim. fruit extracts in LPS-induced RAW 264.7 cells

The objective of this study was to evaluate the anti-inflammatory activities of hot water (JFH) and 70% ethanol (JFE) extracts of Juglans mandshurica Maxim. fruit. JFH and JFE showed cell viability exceeding 90% at 10 μg/mL in RAW 264.7 cells. In lipopolysaccharide (LPS)-treated RAW 264.7 cells, JFH and JFE exhibited inhibitory effects on nitric oxide (NO) production at a concentration of 10 μg/mL, similar to the LPS-untreated group. Anti-inflammatory activity was confirmed by the suppression of protein and mRNA expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-treated RAW 264.7 cells. The protein and mRNA suppression of the inflammation-related mediators iNOS and COX-2 was reduced in a concentration-dependent manner. Futhermore, the production of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in LPS-induced RAW 264.7 cells were evaluated using an enzyme-linked immunosorbent assay (ELISA) kit. The results showed that the production of IL-6 and TNF-α decreased in a concentration-dependent manner. In conclusion, Juglans mandshurica Maxim. fruit extracts may partially modulate inflammatory factors and serve as a potential natural anti-inflammatory agents.