Abstract

CYTOTOXICITY AND APOPTOTIC INDUCTION OF MINTWEED (HYPTIS SUAVEOLENS L. POIT) LEAF EXTRACTS ON HUMAN T-LEUKEMIA CELL LINE, JURKAT CELLS

Sumalee Musika and Korakod Indrapichate*

ABSTRACT

Mintweed, Hyptis suaveolens L. Poit, leaf ethanolic and water extracts (MLE/e and MLE/w) were investigated for cytotoxic effect and apoptotic cell death induction in human T-leukemia cell line, Jurkat cells. The cytotoxicity was evaluated by Alamar blue assay and the apoptosis was detected for nuclear blebbing by Hoechst 33258 staining, DNA fragmentation by SDS-PAGE and related apoptotic protein expression by Western blot analysis. MLE/e and MLE/w significantly reduced the viability of Jurkat cells in concentration dependent manner with IC50 values of 553.52  14.07 and 912.06  16.86 g/ml, respectively. The cell nuclei and nucleosome breakages were detectable as nuclear blebbing and ladders of DNA fragments. Concurrently, Western analysis demonstrated that MLE/e and MLE/w up-regulated Caspase-9, Bcl-2 and Bax expressions. In addition, MLE/e was likely to enhance the growth of normal peripheral blood mononuclear cells, PBMCs, at lower concentrations with IC50 value of 1,356.17  136.78 g/ml. This study is the first report on the cytotoxic and the apoptotic properties of the mintweed extracts on T lymphocyte leukemia. This can be further studied and clinically developed for immunomodulative agents and cancer preventive and therapeutic drugs.

Keywords: Cell proliferation, Nuclear blebbing, DNA fragmentation, Apoptotic proteins.