Sorbitol-induced apoptosis of human leukemia is mediated by caspase activation and cytochrome c release

Arch Toxicol. 2008 Jun;82(6):371-7. doi: 10.1007/s00204-007-0261-y. Epub 2007 Nov 29.

Abstract

It has been reported that sorbitol induces apoptosis in several cancer cell lines. However, the molecular mechanism underlying the sorbitol-induced apoptotic process is not yet clearly understood. In the present study, the intracellular signaling pathways of sorbitol-induced apoptosis in human K562 cells were investigated using both morphological analysis and DNA fragmentation technique. In this study, we demonstrated that sorbitol-induced apoptosis in human K562 cells is a concentration- and time-dependent manner. This sorbitol-induced apoptosis in human K562 cells was also accompanied by the up-regulation of Bax, and down-regulation of p-Bcl-2, but no effect on the levels of Bcl-X(L). Moreover, the sorbitol treatment resulted in a significant reduction of mitochondria membrane potential, increase in the release of mitochondrial cytochrome c (cyt c), and activation of caspase 3. Furthermore, treatment with caspase 3 inhibitor (z-DEVD-fmk) was capable of preventing the sorbitol-induced caspase 3 activity and cell death. These results clearly demonstrate that the induction of apoptosis by sorbitol involves multiple cellular/molecular pathways and strongly suggest that pro- and anti-apoptotic Bcl-2 family proteins, mitochondrial membrane potential, mitochondrial cyt c, and caspase 3, they all participate in sorbitol-induced apoptotic process in human K562 cells.

MeSH terms

  • Antineoplastic Agents / pharmacology*
  • Apoptosis / drug effects*
  • Caspase 3 / biosynthesis*
  • Cytochromes c / biosynthesis*
  • DNA / drug effects
  • DNA Fragmentation
  • Dose-Response Relationship, Drug
  • Drug Screening Assays, Antitumor
  • Humans
  • K562 Cells
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / drug therapy*
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / enzymology
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / pathology
  • Membrane Potential, Mitochondrial / drug effects
  • Mitochondria / drug effects
  • Mitochondria / enzymology
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Sorbitol / pharmacology*

Substances

  • Antineoplastic Agents
  • Proto-Oncogene Proteins c-bcl-2
  • Sorbitol
  • Cytochromes c
  • DNA
  • Caspase 3