Calyptranthes grandifolia O.Berg (Myrtaceae) ethanolic extract inhibits TNF-α gene expression and cytokine release in vitro.

Anti-tumor therapies based on anti-inflammatory effects have been considered in cancer treatment. Survival, proliferation and, resultantly, invasion and metastasis of tumor cells are regulated by local inflammatory mediators. Primary inflammatory cytokines, such as tumor necrosis factor (TNF), are targets for anticancer therapy. Several anti‑inflammatory agents isolated from natural products are becoming important chemopreventive and therapeutic agents for cancer. The present study aimed to investigate the expression of TNF‑α, nuclear factor‑κΒ (NF‑κΒ) and p38α mitogen-activated protein kinase (p38α) genes, associated with proliferation and inflammation in the Caco‑2 cell line treated with ethanolic and hexanic extracts of Calyptranthes grandifolia O.Berg (Myrtaceae). Caco‑2 cells were cultured and treated with plant extract at different concentrations (25, 50, 100 and 200 µg/ml) and stimulated with lipopolysaccharide (LPS). For gene expression, analysis was performed by total RNA extraction followed by synthesis of complementary DNA and analysis by quantitative polymerase chain reaction. The release of TNF‑α cytokine was evaluated by ELISA in RAW 264.7 murine macrophages activated by LPS. Among the evaluated genes, there was a decrease in TNF-α expression at 100 and 200 µg/ml concentrations only with the ethanolic extract (P<0.025). The p38α gene exhibited a tendency to increase expression only when treated with ethanolic extract and the NF‑κΒ gene did not significantly differ compared with the positive control when treated with either analyzed extract. The inhibition of TNF-α cytokine in the RAW 264.7 cell line was significant (P<0.05) in ethanolic extract at 200 µg/ml compared with the positive control (LPS 1 µg/ml). In conclusion, the ethanolic extract may exhibit an anti‑inflammatory activity by inhibiting TNF‑α. However, further studies are required to confirm its potential anti-inflammatory effects.