Abstract
The anti-tumor effect of the Moroccan endemic thyme (Thymus broussonettii) essential oil (EOT) was investigated in vitro using the human ovarian adenocarcinoma IGR-OV1 parental cell line OV1/P and its chemoresistant counterparts OV1/adriamycin (OV1/ADR), OV1/vincristine (OV1/VCR), and OV1/cisplatin (OV1/CDDP). All of these cell lines elicited various degrees of sensitivity to the cytotoxic effect of EOT. The IC50 values (mean +/- SEM, v/v) were 0.40 +/- 0.02, 0.39 +/- 0.02, 0.94 +/- 0.05, and 0.65 +/- 0.03% for OV1/P, OV1/ADR, OV1/VCR, and OV1/CDDP, respectively. Using the DBA-2/P815 (H2d) mouse model, tumors were developed by subcutaneous grafting of tumor fragments of similar size obtained from P815 (murin mastocytoma cell line) injected in donor mouse. Interestingly, intra-tumoral injection of EOT significantly reduced solid tumor development. Indeed, by the 30th day of repeated EOT treatment, the tumor volumes of the animals were 2.00 +/- 0.27, 1.35 +/- 0.20, and 0.85 +/- 0.18 cm(3) after injection with 10, 30, or 50 microL per 72 h (six times), respectively, as opposed to 3.88 +/- 0.50 cm(3) for the control animals. This tumoricidal effect was associated with a marked decrease of mouse mortality. In fact, in these groups of mice, the recorded mortality by the 30th day of treatment was 30 +/- 4, 18 +/- 4, and 8 +/- 3%, respectively, while the control animals showed 75 +/- 10% of mortality. These data indicate that the EOT which contains carvacrol as the major component has an important in vitro cytotoxic activity against tumor cells resistant to chemotherapy as well as a significant antitumor effect in mice. However, our data do not distinguish between carvacrol and the other components of EOT as the active factor.
Highlights
Systemic therapy with cytotoxic drugs is the basis of most effective treatments of disseminated cancers
Given the extensive use of T. broussonettii essential oil in Moroccan traditional medicine, and the hypothesis that this essential oil may have anticancer activity [19,20], we decided to examine the in vitro cytotoxic effect of its essential oil against human ovarian adenocarcinoma IGR-OV1 cell lines, both sensitive and resistant to three chemotherapeutic agents used in the treatment of this gynecological carcinoma, i.e., adriamycin (ADR), cisplatin and vincristine (VCR)
The difference between OV1/CDDP or OV1/ VCR and OV1/P was statistically significant (P < 0.05); no difference in essential oil of thyme (EOT) cytotoxicity was observed between OV1/P and OV1/ADR
Summary
Systemic therapy with cytotoxic drugs is the basis of most effective treatments of disseminated cancers. There is evidence that thymol, a constituent of the essential oil, could be involved in the stimulation of active proliferation of pulp fibroblasts [18] All of these pharmacological activities have been assigned to some widely distributed species of thyme such as T. vulgaris, T. zygis and T. satureioides. Given the extensive use of T. broussonettii essential oil in Moroccan traditional medicine, and the hypothesis that this essential oil may have anticancer activity [19,20], we decided to examine the in vitro cytotoxic effect of its essential oil against human ovarian adenocarcinoma IGR-OV1 cell lines, both sensitive and resistant to three chemotherapeutic agents used in the treatment of this gynecological carcinoma, i.e., adriamycin (ADR), cisplatin and vincristine (VCR). We obtained data on the in vivo antitumor activity of this natural extract
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
