Human hair proteins as natural reactive oxygen species scavengers for in vitro applications

• Main Authors: Lai, Hui Ying, Setyawati, Magdiel Inggrid, Duarte, Catarina Vizetto, Chua, Huei Min, Low, Choon Teck, Ng, Kee Woei
• Other Authors: School of Materials Science and Engineering
• Format: Article
• Language: English
• Published: 2022
• Subjects: Engineering::Materials; Engineering::Materials::Biomaterials; Antioxidant; Biomaterial
• Online Access: https://hdl.handle.net/10356/162994
• Institution: Nanyang Technological University

Human hair proteins are recognized for their intrinsically high cysteine content. They can be solubilized while preserving their highly reductive thiol groups for free radical scavenging applications. The presence of aromatic and nucleophilic amino acids such as methionine, serine, phenylalanine and threonine further contribute to the antioxidative potential of this material. Herein, utilizing the DPPH (2,2-diphenyl-1-picrylhydrazyl) and acellular 2',7'- dichlorodihydrofluorescein diacetate (H2DCFDA) assays, keratins are demonstrated to possess the highest radical scavenging activity among the studied hair proteins. Consequently, protection against hydrogen peroxide-induced oxidative stress in Human Dermal Fibroblasts (HDF) cultured in human hair keratin supplemented media is demonstrated. Quenching of reactive oxygen species(ROS) in the HDF is observed using the CellROX Green dye and the expression levels of antioxidant (HMOX1, SOD2, GPX1) and tumor suppressor (TP53) genes is analyzed using qPCR. Collectively, this study presents further evidence and demonstrates the in vitro application potential of hair proteins, especially keratins, as an antioxidizing supplement.