背景:紫外线照射会引起皮肤刺激,红斑,通过诱导氧化应激和炎症而变黑和屏障破坏。谷胱甘肽,一种主要的抗氧化剂,在皮肤的抗氧化防御网络中起着重要作用。
目的:本研究旨在评估谷胱甘肽氨基酸前体混合物(GAP)对UVB诱导的挑战的转录组和表型终点的体外保护作用。
方法:正常人表皮黑素细胞(NHEM)暴露于GAP,抗坏血酸(AA)及其衍生物。使用CCK8方法评估活力。Melakutis®,色素活体皮肤当量(pLSE)模型,接受重复的50mJ/cm2UVB照射,有或没有GAP治疗。以一致的相机参数捕获模型的图像,并使用分光光度计测量模型的光强度。黑色素含量通过测量405nm处的吸光度来确定。通过Fontana-Masson染色实现黑色素沉积和分布的确认。使用RNA测序(RNA-Seq)进行转录组学分析,并采用机器学习方法进行转录组老化时钟分析。
结果:在NHEM中,与载体对照相比,所有测试化合物均表现出超过85%的活力,表明没有增加的细胞毒性风险。值得注意的是,在相同浓度下,GAP在抑制黑色素产生方面表现出比AA衍生物更大的功效。在pLSE模型中,GAP显著增强了模型的亮度,UVB攻击后黑色素含量和沉积减少,而AA显示最小的影响。GAP有效地抵消了UVB诱导的与色素沉着相关的基因表达改变,炎症和衰老。此外,复发性UVB暴露显著提高了pLSE模型的生物学年龄,GAP治疗缓解的现象。
结论:在NHEM中,与AA衍生物相比,GAP在相同的测试剂量下表现出增强的抑制黑色素产生的效力。在pLSE模型中观察到GAP对UVB照射的显著保护作用,皮肤色素沉着测量和转录组变化证明了这一点。
BACKGROUND: UV radiation exposure causes skin irritation, erythema, darkening and barrier disruption by inducing oxidative stress and inflammation. Glutathione, a master antioxidant, plays an important role in the antioxidant defence network of the skin.
OBJECTIVE: This study aimed to assess the in vitro protective effects of the glutathione amino acid precursors blend (GAP) on transcriptomic and phenotypic endpoints against UVB-induced challenges.
METHODS: Normal human epidermal melanocytes (NHEMs) were exposed to GAP, ascorbic acid (AA) and its derivatives. Viability was assessed using the CCK8 method. Melakutis®, a pigmented living skin equivalent (pLSE) model, underwent repeated 50 mJ/cm2 UVB irradiation with or without GAP treatment. Images of the model were captured with consistent camera parameters, and the model\'s light intensity was measured using a spectrophotometer. Melanin content was determined by measuring absorbance at 405 nm. Confirmation of melanin deposition and distribution was achieved through Fontana-Masson staining. Transcriptomic analysis was conducted using RNA sequencing (RNA-Seq), and a machine learning approach was employed for transcriptomic aging clock analysis.
RESULTS: In NHEMs, all tested compounds exhibited over 85% viability compared to the vehicle control, indicating no heightened risk of cytotoxicity. Notably, GAP demonstrated greater efficacy in inhibiting melanin production than AA derivatives at equivalent concentrations. In pLSE models, GAP notably enhanced model lightness, and reduced melanin content and deposition following the UVB challenge, whereas AA showed minimal impact. GAP effectively counteracted UVB-induced alterations in gene expression linked to pigmentation, inflammation and aging. Moreover, recurrent UVB exposure substantially elevated the biological age of pLSE models, a phenomenon mitigated by GAP treatment.
CONCLUSIONS: In NHEMs, GAP exhibited enhanced effectiveness in inhibiting melanin production at identical tested doses in comparison to AA derivatives. Noteworthy protective effects of GAP against UVB irradiation were observed in the pLSE models, as evidenced by skin pigmentation measurements and transcriptomic changes.