BENZOPHENANTHRIDINE ALKALOIDS OF CHELIDONIUM-MAJUS .2. POTENT INHIBITORY-ACTION AGAINST THE GROWTH OF HUMAN KERATINOCYTES

The benzophenanthridine alkaloids sanguinarine and chelerythrine of Ch elidonium majus, L. (Papaveraceae), were tested for their action again st the growth of human keratinocytes. Cell proliferation was independe ntly determined by directly counting the cells and in the colorimetric MTT assay. Sanguinarine potently inhibited cell growth with an IC50 o f O.2 mu M. Chelidonine, the main alkaloid of Ch. majus, was much less efficient. The extract of the herb of Ch. majus was also effective wi th an IC50 of 1.9 mu M, calculated on the basis of its alkaloid conten t in terms of chelidonine. Keratinocytes were further tested for their susceptibility for the action of sanguinarine and chelerythrine on pl asma membrane integrity, which resulted in a twofold increase in lacta te dehydrogenase (LDH) activity as compared to controls. On the other hand, the activity of the extract of the herb of Ch. majus was due to cytostatic rather than cytotoxic effects, as LDH release was unchanged as compared to controls.