Suppressive activity of protease inhibitors from buckwheat seeds against human T-acute lymphoblastic leukemia cell lines.
The buckwheat protease inhibitor designated BWI-1, a member of the potato inhibitor I family, inhibits trypsin, chymotrypsin, and subtilisin, whereas the buckwheat protease inhibitor designated BWI-2a, a novel protease inhibitor homologous to the vicilin family, inhibits only trypsin. We examined the suppressive activity of BWI-1 and BWI-2a against T-acute lymphoblastic leukemia (T-ALL) cells, such as JURKAT and CCRF-CEM, and human normal blood lymphocytes. Both inhibitors significantly suppressed the growth of T-ALL cells as judged by the soluble 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (tetrazolium/formazan assay). JURKAT cells showed slightly higher susceptibility to buckwheat inhibitors than CCRF-CEM cells. Modification of Arg residue(s) in inhibitors by 1,2-cyclohexandione inactivated their trypsin inhibitory activity, considerably abolishing their suppressive activity. This suggests that the trypsin inhibitory activity is involved in the suppression of growth of human T-ALL cell lines. It was further found that both inhibitors triggered programmed cell death (apoptosis) of these cell strains with DNA fragmentation.
Park
Sung-Soo
SS
Cheju Traditional Food Institute, Cheju Halla College, Jeju-si, Jeju-do 690-708, Korea. parkss@hc.ac.kr
Ohba
Hideki
H
D000485:Allergens / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D052179:Antigens, Plant; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis; D045744:Cell Line, Tumor; D002918:Chymotrypsin / Q000037:antagonists & inhibitors; D006801:Humans; D019169:Jurkat Cells; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000188:drug therapy*; D010940:Plant Proteins / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D011480:Protease Inhibitors / Q000494:pharmacology; D020860:Subtilisin / Q000037:antagonists & inhibitors; D014357:Trypsin / Q000737:chemistry
D000485:Allergens; D052179:Antigens, Plant; D000970:Antineoplastic Agents; C095816:BWI-1 protein, Fagopyrum esculentum; C103575:BWI-2 protein, Fagopyrum esculentum; D010940:Plant Proteins; D011480:Protease Inhibitors; D002918:Chymotrypsin; D014357:Trypsin; D020860:Subtilisin