Ficus sycomorus sap: a psoralene source with potential for the treatment of psoriasis
Psoriasis is a skin disease caused by autoimmune response and affects the 3–8% of population. Several approaches including methotrexate, anthraline, immunosuppresives, vitamin D, and retinoids have been proposed for its treatment, but no effective therapy has been established yet. Novel therapeutic approaches including antibodies such as infliximab, and efalizumab or molecules isolated from natural sources are being under investigation.
Our ongoing research work is focused on the isolation and characterization of psoralene derivatives (furanocoumarins) from the sap of Ficus sycomorus. Since it has been reported that psoralene derivatives have been isolated from aerial parts of Ficus sycomorus, it is expected that psoralenes should also be present in the sap.
A quantity of the sap was collected from the plant stems and was extracted with solvents of different polarity. Furanocoumarins have been detected in the extracts of medium polarity. 1H NMR spectra confirmed the existence of the desirable molecules. Purification of the extracts is in progress to allow for unambiguous structure elucidation of the psoralenes present in the particular sap.
In parallel to the isolation work, small scale clinical trials are being conducted on psoriatic patients. Psoriasis has been confirmed on these patients with histopathologic methods. Psoriatic plaques were coated with crude natural sap. Photos have been taken before, during and after the end of the test and it was shown that the area covered by the psoriatic plaque was decreased.
Acknowledgements: Cyprus Research Promotion Foundation, Grand YGEIA 1104/08