Toxicity evaluation of some traditional African spices on breast cancer cells and isolated rat hepatic mitochondria

Background

Fagara leprieuri (FL), Fagara xanthoxyloïdes (FX), Mondia whitei (MW) and Xylopia aethiopica (XA) are used in many African countries as food spices or in traditional medicine to treat several maladies. In this work, we (a) investigate whether the crude spice extracts present selective cytotoxicity for breast cancer cell lines and (b) investigate whether the same extracts affect the bioenergetics and calcium susceptibility of isolated liver mitochondrial fractions.

Results

All extracts were cytotoxic to the cell lines studied, with the exception of MW, which was less toxic for a normal cell line. Interestingly, some of the extracts did not depolarize mitochondria in intact breast cancer MCF-7 cells, although this effect was observed in a normal breast cancer cell line (MCF-12A). All extracts increased hepatic mitochondrial state 2/4 respiration and decreased the respiratory control ratio and the transmembrane electric potential. Also, the extracts induced the mitochondrial permeability transition (MPT).

Conclusions

Mitochondrial toxicity may be part of the mechanism by which the spices tested cause inhibition of proliferation and death in the cell lines tested. This study also warrants caution in the excessive use of these spices for human consumption.