Jiun-Wen Guo1, Tzu-Kai Lin2, Chin-Han Wu3, Kai-Che Wei4, Cheng-Che E Lan5, Amy Chia-Ying Peng6, Jui-Chen Tsai7, Hamm-Ming Sheu8. 1. Institute of Clinical Pharmacy and Pharmaceutical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan. 2. Department of Dermatology, National Chung Kung University Hospital, College of Medicine, National Chung Kung University, Tainan, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Chung Kung University, Tainan, Taiwan. 3. Department of Dermatology, Kaohsiung Medical University and Hospital, Kaohsiung, Taiwan. 4. Department of Dermatology, Kaohsiung Veterans General Hospital, Taiwan. 5. Department of Dermatology, Kaohsiung Medical University and Hospital, Kaohsiung, Taiwan; Department of Dermatology, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan. 6. Department of Dermatology, National Chung Kung University Hospital, College of Medicine, National Chung Kung University, Tainan, Taiwan. 7. Institute of Clinical Pharmacy and Pharmaceutical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan. Electronic address: jctsai@mail.ncku.edu.tw. 8. Department of Dermatology, National Chung Kung University Hospital, College of Medicine, National Chung Kung University, Tainan, Taiwan; Department of Dermatology, College of Medicine, National Chung Kung University, Tainan, Taiwan. Electronic address: hmsheu@mail.ncku.edu.tw.
Abstract
BACKGROUND: Previous studies have shown that human sebum may play a role in barrier function but with much debate. OBJECTIVE: To elucidate the effects of human sebum on skin barrier function. METHODS: We used hairless mouse skin to study the functional and morphological alternation of epidermis after the application of human sebum. RESULTS: The results showed a significant increase in transepidermal water loss and erythema value, and a decrease in skin hydration, accompanied by epidermal hyperplasia with parakeratosis following sebum application. Nile red staining together with electron microscopic examination confirmed the underlying mechanisms for sebum-induced barrier disruption are related directly to the interaction of sebum with the intracellular lipid lamellae of the SC, thereby leading to the increase in the fluidity of SC intracellular lipids as demonstrated by ATR-FTIR measurement. An inflammatory reaction characterized by an enhanced cytokine cascade, including up-regulation of TNF-α, IL-1α and IL-6, was also observed. On the other hand, there were insignificant expression of thymic stromal lymphopoietin and unchanged serum levels of IgE, suggesting non-immunogenic stimulation by sebum treatment. CONCLUSION: It may be concluded that inflammation induced by excess amount of sebum is more likely an irritant contact dermatitis rather than an allergic one. Moreover, these findings implicated possible relationships between sebum, irritant contact dermatitis, and seborrheic dermatitis.
BACKGROUND: Previous studies have shown that human sebum may play a role in barrier function but with much debate. OBJECTIVE: To elucidate the effects of human sebum on skin barrier function. METHODS: We used hairless mouse skin to study the functional and morphological alternation of epidermis after the application of human sebum. RESULTS: The results showed a significant increase in transepidermal water loss and erythema value, and a decrease in skin hydration, accompanied by epidermal hyperplasia with parakeratosis following sebum application. Nile red staining together with electron microscopic examination confirmed the underlying mechanisms for sebum-induced barrier disruption are related directly to the interaction of sebum with the intracellular lipid lamellae of the SC, thereby leading to the increase in the fluidity of SC intracellular lipids as demonstrated by ATR-FTIR measurement. An inflammatory reaction characterized by an enhanced cytokine cascade, including up-regulation of TNF-α, IL-1α and IL-6, was also observed. On the other hand, there were insignificant expression of thymic stromal lymphopoietin and unchanged serum levels of IgE, suggesting non-immunogenic stimulation by sebum treatment. CONCLUSION: It may be concluded that inflammation induced by excess amount of sebum is more likely an irritant contact dermatitis rather than an allergic one. Moreover, these findings implicated possible relationships between sebum, irritant contact dermatitis, and seborrheic dermatitis.