Planta Med 2015; 81 - PW_171
DOI: 10.1055/s-0035-1565795

Absorption of lycopsamine from a comfrey ointment through human skin

N Jedlinszki 1, AD Beretka 1, B Balázs 2, E Csányi 2, D Csupor 1
  • 1University of Szeged, Faculty of Pharmacy, Department of Pharmacognosy, Szeged, Hungary
  • 2University of Szeged, Faculty of Pharmacy, Department of Pharmaceutical Technology, Szeged, Hungary

In the last three decades more than 350 different hepatotoxic pyrrolizidine alkaloids (PAs) have been identified in several plant species. The application of Symphiti radix is restricted in several countries due to its PA content. In medicines, the daily alkaloid quantity and duration of treatment is limited even in case of topical application. Due to the confirmed good absorption of PAs from the gastrointestinal tract the prohibition of oral use is rational, however the limitation of external application is not supported by relevant scientific data. To date such absorption experiments were not carried out on human skin which would justify the maintenance of restriction related to the application.

The aim of our work was to develop and validate a HPLC-MS/MS method for the quantitative determination of a major PA (lycopsamine) of Symphytum officinale and to carry out pharmacokinetic studies on the absorption of lycopsamine from a traditional Symphytum product through a synthetic membrane and human skin. Pharmacokinetic investigations were carried out on vertical Franz diffusion cell and the lycopsamine content of the samples were quantitate by the validated HPLC-MS/MS method.

Our results show that the amount of absorbed lycopsamine on supporting Porafil membrane in function of time changes between 0.07% and 0.72% through the analysis time (24h). On human skin, the maximal absorption was lower (0.07 – 0.22%). These results are in good agreement with the results of an experiment made in rats (0.1 – 0.4) [1], and reassure the relative safety of the analyzed preparation.

Acknowledgements: This research was supported by the European Union and the State of Hungary, co-financed by the European Social Fund in the framework of TÁMOP 4.2.4. A/2 – 11 – 1-2012 – 0001 'National Excellence Program'.

References:

[1] Brauchli J, Lüthy J, Zweifel U, Schlatter C. Pyrrolizidine alkaloids from Symphytum officinale L. and their percutaneous absorption in rats. Experientia 1982; 38: 1085 – 1087