Cytotoxicities of alkaloids from processed and unprocessed seeds of Strychnos nux-vomica.
OBJECTIVE
To examine the cytotoxicities of 6 crude Strychnos alkaloid fractions from the seeds of Strychnos nux-vomica unprocessed or processed with various traditional processing methods and 13 pure Strychnos alkaloids from the fractions.


METHODS
Using cell culture, their inhibitory effects on Vero cell growth-inhibition assay, and host cell DNA synthesis by [3H]thymidine ([3H]TdR) uptake assay.


RESULTS
The IC50 of processed seeds were 155% and 212% of unprocessed ones in cell growth-inhibition assay and in [3H]TdR uptake assay, respectively. The IC50 of 13 compounds were 0.45-0.80 mmol.L-1 and 0.50-12 mmol.L-1, respectively. The processing method with sand bath exhibited a wide safety margin compared with other traditional processing methods or no processing. The isomers of Strychnos alkaloids and their N-oxides showed much lower cytotoxicities among these alkaloids. Isobrucine N-oxide showed the lowest cytotoxicity. The contents of isomers and N-oxides of Strychnos alkaloids were the highest in the sand processing.


CONCLUSIONS
Processing of nux vomica plays a critical role in its toxicity.
Cai
B C
BC
Institute of Traditional Chinese Medicine & Pharmacology, Nanjing University of Traditional Chinese Medicine, China. bccai@njutcm.edu.cn
Wang
T S
TS
Kurokawa
M
M
Shiraki
K
K
Hattori
M
M
D000470:Alkaloids / Q000633:toxicity*; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002522:Chlorocebus aethiops; D004247:DNA / Q000096:biosynthesis; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000633:toxicity*; D006358:Hot Temperature; D019684:Magnoliopsida / Q000737:chemistry*; D013331:Strychnine / Q000031:analogs & derivatives / Q000633:toxicity*; D013678:Technology, Pharmaceutical; D014709:Vero Cells / Q000187:drug effects
D000470:Alkaloids; D004365:Drugs, Chinese Herbal; C087930:isobrucine; C083806:brucine; D004247:DNA; D013331:Strychnine