황화수소 화합물이 자외선을 조사한 흑색마우스의 표피색소세포내 멜라닌 소체의 형태에 미치는 영향

Abstract

Human skin color is related to the number, size, type and distribution of melanosomes. The number of stage Ⅳ melanosomes is increased in white after irradiation of ultraviolet light and the melanosomes of black are larger than those of whites. Increased melanin pigmentation following ultraviolet radiation is due to increase in tyrosinase activity and numerical increase of functioning melanocytes. Sulfhydryl compounds have been to be potent inhibitors of melanogenesis. They inhibit tyrosinase by combining with the copper requied for enzymatic activity and addition of the SH-compounds to dopaquinone with resulting formation of cysteinyldopa is building block of pheomelanin. In this experiment, we induced activation of melanocytes and melainin pigmentation in the epidermis of C57BL black mice by UVB irradiation. After UVB irradiation, we observed the effect of the two sulfhydryl compounds on melanosomal morphology of epidermal melanocytes in UV-irradiated mice. Both ears of 45 mice have been irradiated with WB daily for 10 days. After irradiation, mice were divided into 3 groups and the intraperitoneal injection of SH-compounds on each groups was done as follows. Group I : 1% sodium carboxymethyl cellulose (CMC) ‥‥‥15 Group Ⅱ: 5% Cysteine ‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥15 Group Ⅲ: 5% Glutathione ‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 15 The intraperitoneal injection of the SH-compounds was done daily for 5 weeks and five mice in each group were sacrificed at the end of the 1st, 3rd and 5th week of the intraperitoneal injection. For the observation of the size of melanosomes and the ratio of melanosomal stage, electron microscopic preparation was done. The results are summerized as follows: 1. Both of Cysteine and Glutathione showed significant diminution in the short axis of melanosomes and the percentage of stage Ⅳ melanosomes of epidermal melanocytes in C57BL black mice skin. 2. The length of short axis of melanosomes in Glutathione-treated group is smaller than those in Cysteine-treated group at the end of 3rd week of intraperitoneal injection. The percentage of stage Ⅳ melanosomes significantly decreased in Glutathione-treated group and Cysteine-treated group at the end of 3rd week and 5th week respectively. 3. In Glutathione-treated group, the short axis of melanosomes and the percentage of stage Ⅳ melanosomes both decreased in proportional to the period of intraperitoneal injectlon. In summary, the present study suggests that both SH-compounds of Cysteine and Glutathione inhibit melanogenesis by the action on epidermal melanocytes by decreasing in the size of melanosomes and the percentage of stage Ⅳ melanosomes, and such inhibiting effect was more markedly seen in the Glutathione-treated group than the Cysteine-treated group.;인체에서 피부색 결정의 주요인자는 멜라닌이며, 멜라닌소체의 수, 크기, 형 및 분포와 연관이 있다. 자외선 조사후 유발되는 멜라닌색소의증가는 주로 색소세포내 tyrosinase의 활성화와 활동성 색소세포 수의 증가에 기인하며, 멜라닌소체의 분포양상은 변화되지 않지만, stageⅣ 멜라닌소체의 수가 증가한다. 멜라닌소체의 크기는 부분적으로 유전적 조절을 받아, 백인에 비해 흑인에서 멜라닌소체의 크기가 더 크고, 밀크커피색 반점이나 반문상 모반에서는 거대멜라닌소체로 나타나며, 저색소병변에서는 그 크기가 매우 작다. 황화수소(SH-group, thiol)화합물은 tyrosine 이 dopa로, dopa가 dopaquinone으로 산화될때 tyrosinase의 작용에 필요한 구리(銅)와 결합하여 멜라닌형성을 억제하거나, dopaquinone에 첨가되어 thiol유도반응산물을 형성하여 eumelanin보다는 pheomelanin을 형성한다고 밝혀졌다. 이에 C57BL 흑색마우스에 ultraviolet B(UVB)를 매일 100mJ/㎠씩 10일간 조사하여 표피 색소세포를 활성화시킨후 투여한 5% Cysteine과 5% Glutathione이 표피 색소세포의 멜라닌소체에 미치는 영향을 관찰하여 다음과 같은 성적을 얻었다. 1. 5% Cysteine과 5% Glutathione은 대조군에 비해 표피 색소세포내 멜라닌소체의 단축길이와 stage Ⅳ 멜라닌소체 비율에 유의한 감소에 보여 멜라닌 형성 억제제로서 의의있는 효과를 나타내었다. 2. 두 실험군간의 비교에서 멜라닌소체 단축길이는 Glutathione 투여군에서 투여 3주후에 Cysteine 투여군보다 의의있게 감소되었으며, stageⅣ 멜라닌소체의 비율은 Glutathione 투여군에서는 투여 3주후에, Cysteine 투여군에서는 투여 5주후에 각각 유의한 감소소견을 보였다. 3. Glutathione 투여군에서는 멜라닌소체 단축길이와 stageⅣ 멜라닌소체의 비율이 투여기간에 비례하여 감소되었다. 이상과 같은 결과로 미루어 보아, 황화수소 화합물인 Cysteine과 Glutathione은 활성화된 표피 색소세포내 멜라닌소체의 단축길이와 stageⅣ 멜라닌소체의 비율을 감소시킴으로써 멜라닌형성을 억제하고, Glutathione은 Cysteine보다 멜라닌형성 억제에 우수한 효과를 나타냄을 알 수 있었다.