Anticancer and antioxidant activities of essential oils of Chiliadenus iphionoides from Jordan: in vitro and in vivo study

Medicinal plants have been used since ancient times and may even be considered the origin of modern medicine. Natural products are a potential source for drug discovery and development of cancer treatments. Several pharmacological therapeutic activities were reported for Chiliadenus iphionoides. This research was designed to evaluate the essential oil of Chiliadenus iphionoides antioxidant potential and antiproliferative activity both in vitro and in vivo. The essential oil of Chiliadenus iphionoides was extracted by hydrodistillation. The chemical composition analysis was performed using gas chromatography. The main compounds identified in Chiliadenus iphionoides essential oil were oxygenated monoterpenes, such as eucalyptol (36.08%). A dose-dependent inhibition of cell proliferation was observed after the treatment of various cell lines (A549 (human lung cancer adenocarcinoma), MDA-MB-231 (triple-negative breast cancer cell line), T47 (human breast cancer cell line), EMT6/P (mouse mammary sarcoma cell line)) with increasing concentrations of the essential oil (0.02-2.5 mg/mL). The essential oil of Chiliadenus iphionoides was more cytotoxic against EMT6 and T47 cells with IC50 values of 0.03 +/- 0.03 and 0.08 +/- 0.009 mg/mL, respectively. The essential oil exhibited low cytotoxicity against a normal VERO cell line (IC50 value > 4 mg/ml). Balb/C mice were inoculated with EMT6/p breast cancer cells and then treated with (60 mg/kg/day intraperitoneal injection) of essential extract for ten days. Interestingly, a significant (p < 0.05) reduction occurred in the tumor size of the treated group compared to the control group. Treatment toxicity was evaluated by measuring liver and kidney parameters. The tumor-bearing mice treated with the Chiliadenus iphionoides extract showed normal serum levels of AST, creatinine, and slight elevation in ALT level. The results indicated that Chiliadenus iphionoides have anticancer properties both in vitro and in vivo. We suggest that eucalyptol, a major active component, is a promising candidate for use as an anticancer agent. However, further molecular investigation is required to understand the molecular bearings of Chiliadenus iphionoides activity.