Two therapeutic challenges: facial vitiligo successfully treated with 1% pimecrolimus cream and 0.005% calcipotriol cream

Pimecrolimus increases the melanogenesis and migration of melanocytes in vitro

Vitiligo is an intriguing depigmentary disorder and is notoriously difficult to be treated. The ultimate goal of vitiligo treatment is to replenish the lost melanocytes by immigration from hair follicle and to restore the normal function of melanogenesis by residual melanocytes. There are two types of topical calcineurin inhibitors called tacrolimus and pimecrolimus, and are recommended as the first-line treatments in vitiligo. Although pimecrolimus is efficacious for the repigmentation of vitiligo, its intrinsic mechanisms have never been investigated in vitro. This research aimed to study the ability of pimecrolimus on stimulating melanogenesis, melanocyte migration and MITF (microphthalmia associated transcription factor) protein expression. Results showed that pimecrolimus at the dosages of 1, 10, 10² nM were neither mitogenic nor cytotoxic to melanocytes. The addition of pimecrolimus at 10, 10² and 10³ nM significantly increased intracellular tyrosinase activity, which was consistent with the elevated content of melanin content at the same concentrations. The peak effect was seen at 72 h in response to 10² nM pimecrolimus. Results of the wound scratch assay and Transwell assays indicate that pimecrolimus is effective in facilitating melanocyte migration on a collagen IV-coated surface. In addition, MITF protein yield reached the highest by pimecrolimus at 10² nM. In brief, pimecrolimus enhances melanin synthesis as well as promotes migration of melanocytes directly, possibly via their effects on MITF protein expression.

Off-label uses of topical vitamin D in dermatology: a systematic review

BACKGROUND

Topical vitamin D is approved by the US Food and Drug Administration for the treatment of psoriasis but is also used off-label in the treatment of a variety of cutaneous diseases despite a lack of evidence-based guidelines.

OBJECTIVE

The objective of this study was to provide evidence-based clinical guidelines for the off-label use of topical vitamin D in the treatment of dermatologic disease.

METHODS

A systematic literature review was conducted via the MEDLINE, Embase, and CENTRAL databases for off-label uses of topical vitamin D analogues in the treatment of dermatologic disease other than psoriasis. The data were synthesized, and evidence-based recommendations were rendered according to the highest level of evidence available.

RESULTS

A total of 165 articles met the inclusion criteria. A moderate to strong recommendation was given for the use of topical vitamin D in combination with corticosteroids and phototherapy in vitiligo and as monotherapy for various ichthyoses, morphea, pityriasis alba, prurigo nodularis, and polymorphous light eruption. There is evidence showing that topical vitamin D is ineffective in the treatment of actinic keratosis, seborrheic keratosis, lichen planus, seborrheic dermatitis, alopecia areata, chemotherapy-induced alopecia, and hypertrophic scars.

CONCLUSION

Topical vitamin D analogues have an important role in the off-label treatment of dermatologic disease, but higher quality studies are still required.

Innovative use of topical calcineurin inhibitors

Topical tacrolimus and pimecrolimus are indicated for treatment of atopic dermatitis, but they have been studied in many off-label uses. Double-blind and open studies have shown favorable results with topical tacrolimus and pimecrolimus in oral lichen planus. In 1 study of oral lichen planus, blood tacrolimus was detected in 54% of patients, but there were no signs of systemic toxicity. Double-blind and open studies of vitiligo have shown favorable results with tacrolimus in combination with excimer laser, especially for lesions over bony prominences and on extremities. Similarly, double-blind studies of vitiligo have shown favorable results when pimecrolimus is combined with narrow-band UVB, especially for facial lesions. Double-blind and open studies of psoriasis have shown favorable results for tacrolimus and pimecrolimus, especially for inverse psoriasis. Topical calcineurin inhibitors have been effective in many other cutaneous disorders, and further studies would help clarify their roles.