Canna indica L. attenuates high-glucose- and lipopolysaccharide-induced inflammatory mediators in monocyte/macrophage

Ethnopharmacological relevance

Canna indica L. (CI) has been widely used as a folklore medicine in tropical and subtropical areas with beneficial effects in numerous diseases, including infection, rheumatism, hepatitis, and it has also been identified as an antioxidant.

Materials and methods

The present study aimed to investigate the effect of Canna indica CI ethanolic extract (CIE) on productions of nitric oxide (NO), prostaglandin E₂ (PGE₂), and interleukin-1β (IL-1β) in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. In addition, the effects of CIE in high glucose (HG)-induced U937 monocytes on mRNA expressions of IL-8 and monocyte chemoattractant protein-1 (MCP-1), and regulation of mitogen-activated protein kinase (MAPK) pathways were also identified.

Results

CIE was found to inhibit the production of inflammatory mediators including NO, IL-1β, and PGE₂ from LPS-induced RAW 264.7 macrophages. The increases in HG-induced mRNA expressions of IL-8 and MCP-1 were also significantly inhibited by CIE. Stimulation of HG in U937 monocytes resulted in activation of p38 MAPK, ERK1/2, and JNK. However, CIE treatment significantly decreased phosphorylation of p38 MAPK, ERK1/2, and JNK.

Conclusion

The present study demonstrated that CIE suppressed the LPS-induced inflammatory mediator production and also inhibited HG-induced inflammatory mediator expression by the regulation of MAPK pathway.