title: Betanin a betacyanin pigment purified from fruits of Opuntia ficus-indica induces apoptosis in human chronic myeloid leukemia Cell line-K562.
abstract: Betalains are water-soluble nitrogenous vacuolar pigments present in flowers and fruits of many caryophyllales with potent antioxidant properties. In the present study the antiproliferative effects of betanin, a principle betacyanin pigment, isolated from the fruits of Opuntia ficus-indica, was evaluated on human chronic myeloid leukemia cell line (K562). The results show dose and time dependent decrease in the proliferation of K562 cells treated with betanin with an IC(50) of 40 microM. Further studies involving scanning and transmission electron microscopy revealed the apoptotic characteristics such as chromatin condensation, cell shrinkage and membrane blebbing. Agarose electrophoresis of genomic DNA of cells treated with betanin showed fragmentation pattern typical for apoptotic cells. Flow cytometric analysis of cells treated with 40 microM betanin showed 28.4% of cells in sub G0/G1 phase. Betanin treatment to the cells also induced the release of cytochrome c into the cytosol, poly (ADP) ribose polymerase (PARP) cleavage, down regulation Bcl-2, and reduction in the membrane potentials. Confocal microscopic studies on the cells treated with betanin suggest the entry of betanin into the cells. These studies thus demonstrate that betanin induces apoptosis in K562 cells through the intrinsic pathway and is mediated by the release of cytochrome c from mitochondria into the cytosol, and PARP cleavage. The antiproliferative effects of betanin add further value to the nutritional characteristics of the fruits of O. ficus-indica.
authors.affiliation: School of Life Sciences, University of Hyderabad, Hyderabad 500 046, India.
authors.forename: Devalraju
authors.initials: D
authors.lastname: Sreekanth
authors.forename: M K
authors.initials: MK
authors.lastname: Arunasree
authors.forename: Karnati R
authors.initials: KR
authors.lastname: Roy
authors.forename: T
authors.initials: T
authors.lastname: Chandramohan Reddy
authors.forename: Gorla V
authors.initials: GV
authors.lastname: Reddy
authors.forename: Pallu
authors.initials: P
authors.lastname: Reddanna
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D050859:Betacyanins / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects*; D004396:Coloring Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D005638:Fruit; D006801:Humans; D020128:Inhibitory Concentration 50; D020014:K562 Cells / Q000187:drug effects / Q000648:ultrastructure; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy / Q000473:pathology; D029747:Opuntia; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D050859:Betacyanins; D004396:Coloring Agents; D010936:Plant Extracts; C020228:betanin