One of the most common unapproved therapies used for early-stage disease is oral 5 or 8-methoxypsoralen
(Psoralen) given with ultraviolet A (UVA) light, referred to as PUVA.
Fifty six patients were randomized into one group receiving PUVA and 8-methoxypsoralen
tablets, and another group receiving NB-UVB with placebo tablets.
Potent tyrosinase activators were further assessed for their potential use as novel melanogenic agents by comparing their melanogenesis-stimulating activities with that of a positive control, 8-Methoxypsoralen
(Lei et al.
Psoralen-UV-A (PUVA) therapy was given using oral 8-methoxypsoralen
and a UV-A dosimetry regimen.
Der-Petrossian M, Seeber A, Honigsmann H, Tanew A: Half-side comparison study on the efficacy of 8-methoxypsoralen
bath-PUVA versus narrow-band ultraviolet B phototherapy in patients with severe chronic atopic dermatitis.
31) Agents with chemopreventive effects in this and other murine models include 8-methoxypsoralen
, (31) farnesol, (32) fatty acid synthase inhibitors, (33) and compounds found in fruits and vegetables, such as hespiridin (34) and quercetin.
Furocoumarins like 8-methoxypsoralen
are present in parsnips and celery.
Pretreatment with UV light renders the chromatin in human fibroblasts more susceptible to the DNA-damaging agents bleomycin, [gamma] radiation and 8-methoxypsoralen
Similar chemicals--primarily 8-methoxypsoralen
and 5-methoxypsoralen--are in celery, parsley, lemons, and other fruits and flora, but usually to a much lesser extent than in limes.
PCR (PerkinElmer, Foster City, CA) and lysis buffers were pretreated with 8-methoxypsoralen
at a final concentration of 25 [micro]g/mL and exposed to long-wave (360 nm) UV light for 15 min to destroy preexisting DNA contaminants.
To combat contamination of Taq preparations, methods have been published to reduce this background PCR by pretreating the Taq polymerase solution with DNase I, ultraviolet irradiation, 8-methoxypsoralen
, or biphasic extractions (54-58).
After sunbathing (a potent source of UVA), the 8-methoxypsoralen
covalently binds to keratinocyte DNA (forming cyclobutane dimers), producing irreversibly damaged DNA (3).