Apoptosis induced by glycoprotein (150-kDa) isolated from Solanum nigrum L. is not related to intracellular reactive oxygen species (ROS) in HCT-116 cells.
This study was carried out to investigate the apoptotic effects of glycoprotein [Solanum nigrum L. (SNL) glycoprotein, 150-kDa] isolated from Solanum nigrum L., which has been used as an antipyretic and anticancer agent in folk medicine. With the purified SNL glycoprotein, we evaluated the cytotoxic and apoptotic effects of SNL glycoprotein on HCT-116 cells, DNA fragmentation and nuclear staining assays, respectively. SNL glycoprotein has an apparent cytotoxic and apoptotic effect at a concentration of 40 microg/ml after 4 h. To further verify the apoptotic effect, we investigated the changes in activity of the apoptotic-related proteins [Bid, cytochrome c, caspases and poly(ADP-ribose)polymerase (PARP)] triggered by SNL glycoprotein, using a western blot analysis. The results in this study indicated that SNL glycoprotein has a stimulatory effect on Bid activation, resulting in the release of cytochrome c, the stimulation of caspase-8, -9 and -3 activities, and the cleavage of PARP in HCT-116 cells. However, SNL glycoprotein did not significantly stimulate an increase in levels of intracellular reactive oxygen species (ROS). From the results in this experiment, it is suggested that SNL glycoprotein induces apoptosis through the mitochondrial apoptotic signal pathway in HCT-116 cells, rather than through intracellular ROS.
Lee
Sei-Jung
SJ
Molecular Biochemistry Laboratory, Institute of Biotechnology, Chonnam National University, Kwangju, 500-757, South Korea.
Lim
Kye-Taek
KT
D000972:Antineoplastic Agents, Phytogenic / Q000633:toxicity*; D000975:Antioxidants / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D002374:Catalase / Q000378:metabolism; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000187:drug effects / Q000648:ultrastructure; D002470:Cell Survival / Q000187:drug effects; D004396:Coloring Agents; D053938:DNA Fragmentation; D005979:Glutathione Peroxidase / Q000378:metabolism; D006023:Glycoproteins / Q000633:toxicity*; D006801:Humans; D008928:Mitochondria / Q000187:drug effects; D010940:Plant Proteins / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D032324:Solanum nigrum / Q000737:chemistry*; D013482:Superoxide Dismutase / Q000378:metabolism
D000972:Antineoplastic Agents, Phytogenic; D000975:Antioxidants; D004396:Coloring Agents; D006023:Glycoproteins; D010940:Plant Proteins; D017382:Reactive Oxygen Species; C508662:glycoprotein 150-kDa, Solanum nigrum; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase