Secoaggregatalactone-A from Lindera aggregata Induces Apoptosis in Human Hepatoma Hep G2 Cells

Abstract

A new secobutanolide, secoaggregatalactone A (1) was isolated from the leaves of Lindera aggregata. Results obtained from the cytotoxicity assay revealed that secoaggregatalactone A exhibited a noticeable cytotoxicity (EC₅₀ = 6.61 μg/mL; 22.1 μM) against the human hepatoma cell line (Hep G2 cell line). According to morphological observations, flow cytometric analysis, and DNA fragmentation analysis, it was proven that the cytotoxicity of secoaggregatalactone A on human cells was due to apoptosis. Moreover, based on the results from the protein expression assay and confocal laser scanning microscope observations, it is assumed that secoaggregatalactone A induced apoptosis through the mitochondria pathway by way of cleavage of Bit to release cytochrome C and activate caspases-9 and -3, and then degradation of PARP.

Key words

Secoaggregatalactone A - apoptosis - cytotoxicity - Lindera aggregata - Lauraceae - mitochondrial pathway

References

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