Anti-inflammatory evaluation of Scurrula ferruginea (jack) danser parasitizing on Tecoma stans (L.) HBK in LPS/IFN- γ -induced RAW 264.7 macrophages

Ethnopharmacological relevance: Scurrula ferruginea (Jack) Danser (locally known as 'Dedalu' or 'dian nan ji sheng' in Malaysia and China) is a hemi-parasitic shrub that is widely used as herbal medicine to treat inflammation, rheumatism, and stroke. However, the scientific basis of its anti-inflammatory function and mechanism remain to be proven. Aim of the study: To evaluate the anti-inflammatory activity as well as the preliminary mechanism of S. ferruginea parasitizing on Tecoma stans. Materials and methods: The anti-inflammatory capability of freeze-dried stem aqueous extract was assessed via inhibition of inflammatory cytokines interleukin(IL-) 1 beta, IL-6, IL-10, and tumor necrosis factor-alpha (TNF-alpha) production in lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) stimulated RAW 264.7 macrophages. The underlying anti-inflammatory mechanism was deciphered through reverse transcriptase and real time quantitative polymerase chain reactions (RT-PCR and qPCR) for inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), IL-1 beta, and TNF-alpha mRNA expression. Results: The results exhibited that aqueous extract of freeze-dried S. ferruginea stem sample concentration dependently inhibited IL-1 beta protein production along with the down regulation of iNOS and IL-1 beta mRNA expression. Moreover, it significantly suppressed the protein release of IL-6 and IL-10 in a concentration dependent manner. However, it slightly reduced TNF-alpha at higher sample concentration (250 mu g/mL) without affecting the mRNA expression levels of COX-2 and TNF-alpha. Conclusions: This study suggests that S. ferruginea parasitizing on Tecoma stans exerted anti-inflammatory capability attributed to inhibition of iNOS and IL-1 beta mRNA expression, NO creation, IL-1 beta, IL-6, IL-10, and TNF-alpha protein production, indicating this plant might be a useful plant-derived candidate against inflammation.

Automated summary

The study demonstrated that Scurrula ferruginea parasitizing on Tecoma stans showed anti-inflammatory activity by inhibiting the production of inflammatory cytokines and regulating gene expression, suggesting its potential as a plant-derived candidate for inflammation treatment.