In-vitro scientific validation of anti-inflammatory activity of Punica granatum L. on Leukemia monocytic cell line

The induction of the inflammatory cascade results in the production of a number of inflammatory mediators, including prostaglandin E2 (PGE2), nitric oxide (NO), and proinflammatory cytokines like TNF-, IL-, and IL-6. This study examined the cytotoxicity and anti-inflammatory properties of a methanolic crude extract of Punica granatum L. peel (PPM) on monocytic leukaemia cell line (THP-1). The PPM along with Quercetin as reference was used to assess the cytotoxic effect on THP-1 cells and describe its effect on pro-inflammatory cytokines such as COX-2, TNF-α, IL-6 against cancer cell line by flow cytometry. The percentage of viable cells significantly decreased which correlates to non-toxicity whereas quercetin was found to be highly toxic, the IC50 could not be calculated because of drug precipitation. There was a significant decrease in the expressions of inflammatory cytokines upon pre-treatment of the cells with PPM prior to LPS stimulation. Our findings indicate that no cytotoxicity was observed after the treatment of THP-1 cells with PPM (25-400 µg/ml), but at higher concentration (400µg/ml), the cell viability decreased to 84% and attenuated the expression level of inflammatory cytokines. The inhibitory effect of the extract on pro-inflammatory factors production may provide a theoretical source on upcoming treatment of inflammation.