Open AccessIn vitro cytotoxicity of Gymnema montanum in human leukaemia HL ‐60 cells; induction of apoptosis by mitochondrial membrane potential collapse
Author(s) -
Ramkumar K. M.,
Manjula C.,
Elango B.,
Krishnamurthi K.,
Saravana Devi S.,
Rajaguru P.
Publication year - 2013
Publication title -
cell proliferation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.647
H-Index - 74
eISSN - 1365-2184
pISSN - 0960-7722
DOI - 10.1111/cpr.12033
Subject(s) - apoptosis , cytotoxicity , annexin , superoxide dismutase , peripheral blood mononuclear cell , microbiology and biotechnology , chemistry , glutathione peroxidase , glutathione , biology , lipid peroxidation , biochemistry , oxidative stress , in vitro , enzyme
Objectives Gymnema montanum Hook, an Indian Ayurvedic medicinal plant, is used traditionally to treat a variety of ailments. Here, we report anti‐cancer effects and molecular mechanisms of ethanolic extract of G. montanum ( GLE t) on human leukaemia HL ‐60 cells, compared to peripheral blood mononuclear cells. Materials and methods HL ‐60 cells were treated with different concentrations of GLE t (10–50 μg/ml) and cytotoxicity was assessed by MTT assay. Levels of lipid peroxidation, antioxidants, mitochondrial membrane potential and caspase‐3 were measured. Further, apoptosis was studied using annexin‐V staining and the cell cycle was analyzed by flow cytometry. Results GLE t had a potent cytotoxic effect on HL ‐60 cells ( IC 50 ‐20 μg/ml), yet was not toxic to normal peripheral blood mononuclear cells. Exposure of HL ‐60 cells to GLE t led to elevated levels of malonaldehyde formation, but to reduced glutathione, superoxide dismutase, catalase and glutathione peroxidase activities ( P < 0.05). Induction of apoptosis was confirmed by observing annexin‐V positive cells, associated with loss of mitochondrial membrane potential. Cell cycle arrest at G0/G1 was observed in GLE t‐treated HL ‐60 cells, indicating its potential at inducing their apoptosis. Conclusions Findings of the present study suggest that G. montanum induced apoptosis in the human leukaemic cancer cells, mediated by collapse of mitochondrial membrane potential, generation of reactive oxygen species and depletion of intracellular antioxidant potential.