Jb. Nissen et al., Decrease in enkephalin levels in psoriatic lesions after calcipotriol and mometasone furoate treatment, DERMATOLOGY, 198(1), 1999, pp. 11-17
Background: Enkephalins are opioid peptides that can modulate immune respon
ses and inflammatory processes. Furthermore, they inhibit keratinocyte prol
iferation/differentiation in vitro. Previously, we have shown that enkephal
ins are present in increased amounts in lesional psoriasis. Objective: To d
etermine the effect of topical treatment with the vitamin D analogue calcip
otriol and the corticosteroid mometasone furoate on the level of methionine
-enkephalin (enk) in psoriatic lesions. Methods: Twelve psoriatic patients
were treated with calcipotriol and mometasone furoate for 14 days without o
r with hydrocolloid occlusion. Keratome biopsies were obtained from treated
and untreated skin, and the extracted enk was quantified by radioimmunoass
ay. Furthermore, punch biopsies were obtained for immunohistochemical analy
sis. Results: Clinically, both calcipotriol and mometasone furoate improved
psoriasis to the same degree, the effects being more pronounced after occl
usion, Histologically, treatment with mometasone furoate without occlusion
decreased both the epidermal thickness/parakeratosis and the number of derm
al immunocompetent cells (CD3- and CD68-positive cells). In contrast, treat
ment with calcipotriol without ocelusion reduced the epidermal thickness an
d the degree of parakeratosis but decreased the number of CD3- and CD68-pos
itive cells only slightly. The mean enk level was decreased by 26 and 86% b
y calcipotriol without and with occlusion and by 16 and 63% by mometasone f
uroate without and with occlusion, respectively. The decreases in the enk l
evels corresponded to the degree of clinical improvement but not to the his
tological changes. Conclusion: The increased levels of enk in psoriatic les
ions are reduced in parallel with the clinical improvement induced by a top
ical vitamin D analogue and a corticosteroid. Because enkephalins can modul
ate epidermal differentiation and inflammatory processes, the findings indi
cate that enkephalins may play a role in the pathogenesis of psoriasis.