Phytochemical analysis, cytostatic, cytotoxic, and anti-inflammatory effects of Arum palaestinum, Ocimum basilicum, and Trigonella foenum-graecum in human monocytic cell line (THP-1)-derived macrophages

Abstract

The significance of the crosstalk between pro-inflammatory mediators and carcinogenesis is widely discussed. These mediators play decisive roles at different stages of tumor development, including initiation, promotion, and metastasis. Arum palaestinum Boiss., Ocimum basilicum L., and Trigonella foenum-graecum L. and their crude extracts are traditionally used in the Arab and Islamic herbal medicine to treat a variety of cancers and inflammatory illnesses. Human monocytic cell line (THP-1)-derived macrophages were used to evaluate anti-inflammatory, cytotoxic, and cytostatic effects of the ethanolic plant extracts. Cytotoxic and cytostatic effects were measured with the MTT assay. In addition, the production levels of pro-inflammatory mediators (TNF-α, IL-6, and nitric oxide) and anti-inflammatory cytokine (IL-10) were measured in lipopolysaccharide (LPS)-activated THP-1-derived macrophages in the absence and presence of increasing concentrations of the three plant extracts. The three plant extracts suppressed the production of NO and TNF-α and IL-6, and enhanced the production of IL-10 in LPS-activated THP-1-derived macrophages. In addition, these extracts inhibited the growth of THP-1-derived macrophages in a concentration-dependent manner at nontoxic concentrations. T. foenum-graecum exhibited the highest cytostatic effects with an IC50 of 512 µg/ mL compared to O. basilicum (no cytostatic effects) and A. palaestinum (IC50=1274 µg/mL). Even though more studies are needed to elucidate the mechanisms of observed cytostatic and anti-inflammatory effects, to some extent, these effects could be attributed to the flavonoids, phenolic compounds, and tannin content detected in the plants’ extracts.