Effects of Calcium on the Epidermis in a Skin Organ Culture / 대한피부과학회지

BACKGROUND: Calcium plays a role in the proliferation and differentiation of keratinocytes. In a normal situation, the calcium concentration forms a gradient across the epidermal layers. Calcium is sparse in the basal layer and spinous layer. Skin organ culture is a useful model for conducting research on various aspects of skin biology. Skin organ culture systems are used for defining factors that affect homeostasis when elucidating the modulatory effects of biologic response modifiers, drugs and physical agents on the skin and also when studying complex aspects of cutaneous biology in normal and diseased skin. OBJECTIVE: In this study, we investigated the effects of extracellular calcium on the epidermis in a skin organ culture. METHODS: We compared the skin organ culture patterns under various culture conditions (calcium 0.1, 0.7, 1.4 and 2.0 mM). RESULTS: H&E staining showed different phenotypes according to the calcium concentration and IHC also showed different phenotyes compared to that of keratin 10, involucrin, filaggrin, loricrin and PCNA. CONCLUSION: As a result, we concluded that the calcium gradient is also an important factor in skin organ culture to maintain the vivo-like environment and the appropriate calcium concentration is 1.4 mM.

Short-term, High Dose Methylprednisolone and Narrowband UVB Combination Therapy for 2 Patients with Vitiligo / 대한피부과학회지

Systemic corticosteroid arrests the progression of vitiligo and leads to repigmentation, but it may produce side effects. It has been reported that the maximum effect for corticosteroid can be achieved without major side effects when it is used at high doses over a short period of time. Recently, narrowband UVB has been used to treat vitiligo. However, there have been no reports on the effectiveness for a combined treatment with narrowband UVB and systemic corticosteroid. We encountered 2 cases of vitiligo patients who had rapid and effective repigmentation after combination therapy with high dose methylprednisolone and narrowband UVB. Intravenous high dose (25 mg/kg) of methylprednisolone for 3 days was followed by narrowband UVB once or twice weekly. After 2 months, rapid improvements were seen in both patients with >75% repigmentation. Combination treatment with high dose methylprednisolone therapy and narrowband UVB may be an effective therapeutic option for vitiligo.

Expression of Neutrophil Gelatinase-Associated Lipocalin in Calcium-Induced Keratinocyte Differentiation

In a previous search for the differentially expressed genes in keratinocyte differentiation, we identified neutrophil gelatinase-associated lipocalin (NGAL) as a calcium- induced gene. In this study, we further verified the expression of NGAL in cultured keratinocytes as well as in several skin diseases. Reverse transcription-polymerase chain reaction (RT-PCR), Western blot, and ELISA clearly showed that NGAL expression was markedly increased in calcium-induced keratinocyte differentiation in vitro. However, in our previous report, NGAL expression was not detected in normal skin tissue except for hair follicle by in situ hybridization and immunohistochemistry, indicating the difference of cell status between in vitro and in vitro conditions. Interestingly, NGAL expression was highly increased in psoriasis-like inflammatory disorders (lichen planus and pityriasis rubura pilaris) and skin cancers (keratoacanthoma and squamous cell carcinoma), implying that NGAL may be related with the epidermal hyperplasia. Collectively, these results reveal the potential importance of NGAL in the maintenance of skin homeostasis.