Antitumor and Immunomodulatory Properties of the Bulgarian Endemic Plant Degen et Neič. (Lamiaceae).

Extracts obtained from different species have been shown to possess important biological properties. The present study aimed to investigate the cytotoxicity, antitumor and immunomodulatory potential of the endemic plant (Lamiaceae) and thus, reveal new aspects of its biological activity. Methanolic extract obtained from inflorescences was analyzed for cytotoxicity against mammalian cell lines. The antitumor potential of the sample was determined using human cervical and lung adenocarcinoma cells (HeLa and A549). Programmed cell death-inducing effects against HeLa cells and peripheral blood lymphocytes, as well as immunomodulatory properties of the extract were determined by flow cytometry analysis. The research results demonstrated that the extract has significant inhibitory potential against HeLa cells (mean IC value 119.2 μg/mL). The sample selectively induced apoptotic death in tumor cells. Cytotoxic effects towards mouse cell lines were detected following treatment with high concentrations of extract (200 and 250 μg/mL). Twenty-four-hour ex vivo incubation of peripheral blood leucocytes in growth medium containing plant extract induced prominent effects in distinct immune cell populations. They included elevated levels of CD25 and CD56 T cells' lymphocytes, particularly CD4CD25 and CD8CD56 cells. The present study demonstrates that inflorescence extract possesses potential beneficial antitumor and immunomodulatory activity and could serve as a source of bioactive compounds with biomedical application.