Saussurea gossypiphora extracts reduce inflammation by reversing inflammatory cytokine levels in in-vitro and in-vivo

Abstract

Background

Saussurea gossypiphora D. Don. (SGD) is a medicinal herb found at high altitudes in Himalayan region and has immense medicinal value. This study reports the analysis of biological activity of methanolic extracts of flowers of SGD .

Methods

The antioxidant activities of Methanolic extracts of flowers of Saussurea gossypiphora (MESGD) were examined using 1,1-diphenyl-2-picrylhydrazyl assay. Gas Chromatography Mass Spectrometric investigation revealed the presence of various bio-active constituents. Carrageenan was used to assess the anti-Inflammatory activity in the right hind paw edema of male Wistar rats. Effect of MESGD on inflammasome pathway was studied by performing ELISA for IL-1β, TNF-α and confirmed by immunoblotting for NLRP3 and Caspase 1 in THP1 cells. Finally, RAW 264.7 cells treated with LPS were assessed for the synthesis of Nitric Oxide to confirm anti-inflammatory activity of MESGD.

Results

The analysis of GC–MS of MESGD revealed the presence of various bio-active components such as Spirohexane-1-Carboxylic acid, ethyl ester; 1-Methyl-1-n-decycloxy-1-silacyclobutane; 1, 2, 4-Trioxolane-2-octanoic acid, 5-octyl, methyl ester; DPPH assay showed inhibition of free radicals by 40 - 95.66 % in the range of 25 – 1000 µg/mL concentrations, comparable with Ascorbic acid. The amount of NO in Lipopolysaccharide treated RAW 264.7 cells was decreased in MESGD pre-treated cells. LPS treated THP-1 macrophages pre-treated with MESGD showed significant suppression of pro-Inflammatory cytokines, specifically TNF-α and IL-1β via suppression of NLRP3 mediated inflammasome pathway. Wistar rats upon carrageenan induced paw edema showed significant reduction in paw edema and volume upon oral administration of MESGD within 3 h, indicating its significant anti-inflammatory activity. Rats treated with MESGD showed minimum side effects such as liver damage, hemoglobin, platelet and WBC count were increased when compared with animals treated with standard anti-inflammatory drug Indomethacin.

Conclusion

MESGD showed significant anti-inflammatory activity. This activity seems to be mediated by the suppression of NO by MESGD and also via suppression of NLRP3 mediated inflammasome pathway leading to suppression of inflammatory cytokines IL-1β and TNF-α. These results validate traditional assertions and offer valuable insights for the pharmacological applications of SGD. Further research is needed for devising formulation of natural anti-inflammatory compound based gels/ointments utilizing SGD.