Six new cytotoxic and anti-inflammatory 11, 20-epoxy-ent-kaurane diterpenoids from Isodon wikstroemioides / 中国天然药物

The present study was designed to determine the chemical constituents of EtOAc extracts of the aerial parts of Isodon wikstroemioides. Compounds 1-8 were isolated and purified by normal-phase silica gel and reversed-phase C18silica gel column chromatography and HPLC. Their structures were elucidated by extensive spectroscopic methods. Most of them were evaluated for their in vitro cytotoxicity against human cancer HL-60, SMMC-7721, A-549, MCF-7, and SW-480 cells and their inhibitory activity against nitric oxide (NO) production in LPS-activated RAW264.7 macrophages. Among the eight 11, 20-epoxy-ent-kauranoids isolated, compounds 1-6 (isowikstroemins H-M) were new diterpenoids. Compounds 1, 3, and 7 exhibited significant cytotoxicity with IC50 values ranging from (0.84 ± 0.02) to (4.09 ± 0.34) μmol · L(-1), while compounds 4 and 5 showed selective cytotoxicity. In addition, compounds 1, 3, 4, and 7 exhibited inhibitory activity against nitric oxide (NO) production in LPS-activated RAW264.7 macrophages. These results provide a basis for future development of these compounds as anti-cancer and anti-inflammatory agents.

Longikaurin A induces apoptosis of multiple myeloma H929 cells / 中国实验血液学杂志

The aim of this study was to investigate the biological effect of longikaurin A on multiple myeloma H929 cells. Effects of oridonin and longikaurin A on proliferation of H929 cells were evaluated by CCK-8 assay. Cell morphological features of H929 cells were examined under inverted phase contrast microscope. Apoptosis was determined by Annexin V/PI staining. Expression of caspase-3, caspase-9, and PARP were detected by Western blot. Reactive oxygen species (ROS) level was determined by DCFDA assay. The results showed that longikaurin A (IC(50) 0.85 µmol/L) was more effective than oridonin ((IC(50) 10.66 µmol/L) to inhibit the proliferation of H929 cells. Treatment with longikaurin 2 µmol/L significantly increased the percentage of Annexin V positive cells. Caspase-3 and caspase-9 were activated and PARP, one substrate of caspase-3, was cleaved into 85 kDa fragments. The ROS scavenger N-acetyl-cysteine significantly blocked apoptosis induced by longikaurin A. However, longikaurin A did not increase the ROS level in H929 cells. It is concluded that longikaurin A is more effective than oridonin to induce apoptosis in multiple myeloma H929 cells without increasing the ROS level.