黑色素和面部皮肤荧光性作为与年龄相关的泛黄变色的标志物。

Melanin and facial skin fluorescence as markers of yellowish discoloration with aging.

机构信息

POLA Laboratories, POLA Chemical Industries Inc, Yokohama, Japan.

出版信息

Skin Res Technol. 2009 Nov;15(4):496-502. doi: 10.1111/j.1600-0846.2009.00396.x.

DOI:10.1111/j.1600-0846.2009.00396.x

PMID:19832964

Abstract

BACKGROUND

Although one clinical sign of aging and/or photoaging is a yellowish discoloration of the facial skin, little is known about the cause of this change. In addition to the increase in the epidermal melanin content, it has been suggested that advanced glycation end products (AGEs), which are known to accumulate in photoaged skin, may affect this discoloration.

AIM

The objective of this pilot study was to non-invasively investigate the roles of melanin and AGEs in this yellowish discoloration of the facial skin.

METHODS

We examined the spectral reflectance at the cheek in 40 healthy Japanese women of various ages (mean age, 38.1 years) using a reflectance spectrophotometer and a spectrofluorimeter. The degree of yellowish tint was evaluated in terms of b(*). The amount of melanin in the skin was evaluated by calculating the melanin index (MI) A(640)-A(670) [A(lambda): log(10) (1/reflectance) at a wavelength of lambda]. The amount of AGEs was roughly evaluated using the AGEs index, which is thought to linearly correlate with the amount of intrinsic fluorescence markers irrespective of the concentration of melanin and is defined as follows: AGEs index=I(5)/SQR (I(1)xI(2)). In this equation, the intensities of reflectance are I(1) at an excitation wavelength of 335 nm, I(2) at an emission wavelength of 390 nm and I(5) at 390 nm under an excitation wavelength of 335 nm.

RESULTS

Both b() and the AGEs index were significantly correlated with subject age (r=0.34, P<0.05 and r=0.68, P<0.0001, respectively). Significant correlations were also observed between MI and b() (r=0.63, P<0.0001) and between the AGEs index and b(*) (r=0.53, P<0.0005). However, no significant correlations were seen between MI and the AGEs index.

CONCLUSION

The AGEs index does not appear to be influenced by the amount of melanin and may be utilized as an indicator of the amount of AGEs in the skin. AGEs are likely to play a role in the yellowish discoloration of skin with aging.

摘要

背景

虽然面部皮肤老化和/或光老化的一个临床特征是皮肤发黄，但对于这种变化的原因知之甚少。除了表皮黑色素含量增加外，还认为已知在光老化皮肤中积累的晚期糖基化终产物 (AGEs) 可能会影响这种变色。

目的

本初步研究的目的是无创性研究黑色素和 AGEs 在面部皮肤发黄中的作用。

方法

我们使用反射分光光度计和分光荧光计检查了 40 名不同年龄（平均年龄 38.1 岁）的日本健康女性脸颊的光谱反射率。使用 b(*) 评估黄色色调的程度。皮肤中的黑色素量通过计算黑色素指数 (MI) A(640)-A(670) [A(lambda)：在波长 lambda 处 1/反射率的 log(10)] 来评估。使用 AGEs 指数粗略评估 AGEs 的量，该指数被认为与内在荧光标志物的量呈线性相关，而与黑色素的浓度无关，定义如下：AGEs 指数=I(5)/SQR (I(1)xI(2))。在这个方程中，反射率的强度是 I(1)在 335nm 的激发波长下，I(2)在 390nm 的发射波长下，I(5)在 335nm 的激发波长下的 390nm。

结果

b() 和 AGEs 指数均与受试者年龄呈显著相关(r=0.34，P<0.05 和 r=0.68，P<0.0001)。MI 与 b() 之间也存在显著相关性(r=0.63，P<0.0001)和 AGEs 指数与 b(*) 之间的相关性(r=0.53，P<0.0005)。然而，MI 与 AGEs 指数之间没有观察到显著相关性。