L'Oréal Research and Innovation, Clichy, France.
L'Oréal Research and Innovation, Rio de Janeiro, Brazil.
J Eur Acad Dermatol Venereol. 2024 Jan;38(1):214-222. doi: 10.1111/jdv.19486. Epub 2023 Sep 12.
Of all ultraviolet (UV) radiations reaching the earth, UVA1 rays have a higher potential of penetrating and producing clinically harmful consequences. While UV radiations up to 370 nm are well-blocked by current sunscreens, a photoprotection gap remains for the UVA1 wavelengths between 370 and 400 nm.
This study was to assess under outdoor summer conditions the impact on pigmentation and skin ageing signs of a protection against UVA1 using methoxypropylamino cyclohexenylidene ethoxyethylcyanoacetate (MCE) filter added to a reference SPF50 sunscreen, in comparison with the same sunscreen without the MCE filter.
This prospective randomized comparative intra-individual study was conducted in 113 women in Brazil and China. Subjects had their face and two forearms exposed twice-daily to a 1-h outdoor sunlight exposure over 8 weeks. Before exposure, the SPF50 sunscreen containing 3% MCE was applied on one half-face and one forearm and the same reference product without MCE on the other half-face and forearm. Primary study endpoint was skin colour changes (chromametry). Other endpoints included expert panel grading of pigmentation and facial skin ageing, and naïve panel assessment of facial skin radiance and homogeneity.
After 8 weeks, the skin was darker on both forearms but the increase in sun-induced pigmentation was smaller with the SPF50/MCE sunscreen. Expert panel evaluations showed no change in severity scores for pigmentation and a decreased severity scores for facial skin ageing in areas protected with the SPF50/MCE product: severity scores in areas protected with the SPF50 alone were either increased (pigmentation) or unchanged (skin ageing). Naïve panel evaluations of skin radiance and homogeneity showed statistically significant superiority of the SPF50/MCE product.
Overall, this study demonstrates that a protection with the SPF50/MCE sunscreen significantly reduces pigmentation and ageing signs compared to the same SPF50 sunscreen.
所有到达地球的紫外线（UV）辐射中，UVA1 射线具有更高的穿透能力，并产生临床上有害的后果。虽然目前的防晒霜能很好地阻挡波长在 370nm 以下的紫外线，但对于波长在 370nm 至 400nm 之间的 UVA1 仍存在防晒保护缺口。
本研究旨在评估在户外夏季条件下，使用添加甲氧基丙氨基环己烯基二乙氧基乙基氰基乙酸酯（MCE）滤光剂的参考 SPF50 防晒霜对色素沉着和皮肤老化迹象的影响，与不含 MCE 滤光剂的相同防晒霜进行比较。
这是一项在巴西和中国进行的前瞻性随机对照个体研究，共纳入 113 名女性。在 8 周内，受试者每天两次将面部和两个前臂暴露于 1 小时的户外阳光照射下。暴露前，将含有 3% MCE 的 SPF50 防晒霜涂抹于一半面部和一半前臂，而另一半面部和前臂则涂抹不含 MCE 的相同参考产品。主要研究终点为皮肤颜色变化（色度计）。其他终点包括专家小组对色素沉着和面部皮肤老化的评分，以及对面部皮肤光泽度和均一性的非专业小组评估。
8 周后，两个前臂的皮肤都变黑了，但使用 SPF50/MCE 防晒霜后，诱导的色素沉着增加较小。专家小组评估显示，使用 SPF50/MCE 产品保护的区域的色素沉着严重程度评分无变化，面部皮肤老化严重程度评分降低：使用 SPF50 单独保护的区域的严重程度评分要么增加（色素沉着），要么不变（皮肤老化）。非专业小组对皮肤光泽度和均一性的评估显示，SPF50/MCE 产品具有统计学上的优越性。
总的来说，这项研究表明，与相同的 SPF50 防晒霜相比，使用 SPF50/MCE 防晒霜能显著减少色素沉着和老化迹象。
