Anti-inflammatory effect of Varthemia iphionoides extracts against prostate cancer in vitro

Abstract

Varthemia iphionoides is a Jordanian medicinal plant with several health-promoting properties, including antibacterial, antioxidant and anticancer activities. However, its anti-inflammatory properties have been poorly investigated up to date. The current study aimed to investigate the anti-inflammatory effect of V. iphionoides by measuring the production of interleukin-6 in response to a pro-inflammatory stimulus (bacterial lipopolysaccharide) in in vitro cell models of human MRC-5 and PC3 cells. We observed a significant reduction in lipopolysaccharide-induced interleukin-6 release in response to V. iphionoides (125 μg/mL) in both non-cancerous fibroblast MRC-5 and prostate cancerous PC3 cells. However, the anti-inflammatory effect of this medicinal plant was stronger when MRC-5 cells were treated with an aqueous extract, while the methanolic extract was more potent in PC3 cells. The effect of V. iphionoides in reducing interleukin-6 production was not due to its cytotoxicity, and future studies are required to elucidate the mechanisms of action by which this medicinal plant modulates inflammatory responses. In conclusion, the results of our study represent the first report of the potential protective effect of water and methanolic extracts of V. iphionoides against pro-inflammatory stimuli in fibroblasts and cancer cells of human origin, and it is critically important to identify the phytochemical compounds responsible for this effect.