Chemical and cytotoxic constituents from the leaves of Cinnamomum kotoense.
Three new butanolides, kotomolide A (1), isokotomolide A (2), and kotomolide B (3), and a new secobutanolide, secokotomolide A (4), along with 21 known compounds were isolated from the leaves of Cinnamomum kotoense. Their structures were determined by spectroscopic analyses. Compound 4 was found to induce significant cell death in the human HeLa cell line. Apoptotic-related DNA damage can be positively related to the dose of compound 4. The DNA damage was measured by the percentage of subG1 (24 h after the treatment of compound 4) as determined by cell cycle analysis and TUNEL assay. Treatment with 4 significantly increased intracellular H2O2 and/or peroxide, nitric oxide (NO) at 1, 3, and 24 h. Our results also showed that compound 4 induced (a) noticeable reduction of mitochondrial transmembrane potential (DeltaPsi(m)), (b) activation of caspase 3/7, and (c) up-regulation of the p53 expression. Compound 4-induced DNA damage was found to markedly decrease when the cells were pretreated with an intracellular glutathione supplement (glutathione ethyl ester). These results suggest that an increase of H2O2 and/or peroxide by compound 4 is the initial apoptotic event. The intracellular GSH depletion is a critical event in compound 4-induced apoptosis in HeLa cells.
Chen
Ching-Hsein
CH
Graduate Institute of Biopharmaceutics, College of Life Sciences, National Chiayi University, Chiayi 600, Taiwan, Republic of China.
Lo
Wen-Li
WL
Liu
Ya-Chen
YC
Chen
Chung-Yi
CY
D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3; D053179:Caspase 7; D020169:Caspases / Q000378:metabolism; D027424:Cinnamomum / Q000737:chemistry*; D004247:DNA / Q000032:analysis*; D004249:DNA Damage / Q000187:drug effects; D005434:Flow Cytometry; D006367:HeLa Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000032:analysis / Q000378:metabolism; D015394:Molecular Structure; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D013624:Taiwan; D016159:Tumor Suppressor Protein p53 / Q000187:drug effects
D000970:Antineoplastic Agents; D016159:Tumor Suppressor Protein p53; C512093:kotomolide A; C512094:kotomolide B; D004247:DNA; D006861:Hydrogen Peroxide; C505407:CASP3 protein, human; C505520:CASP7 protein, human; D053148:Caspase 3; D053179:Caspase 7; D020169:Caspases; D015107:4-Butyrolactone