title: The Role of Free Radicals in the Photodynamic Treatment of Fibrotic Skin Diseases.
abstract: The first derivatives of gelatin and type I collagen fluorescence spectra were characterized in order to describe the effect of free radicals on pyridinoline (PYD) cross-links. The different gas saturation conditions were used to investigate the effect of different free radicals. An analysis of first derivative fluorescence spectra suggests that PYD cross-link fluorescence emission is composed of three peaks in gelatin, but only two in type I collagen. The PYD cross-link was photo-degraded more than other gases in the presence of O2. This suggests that the singlet oxygen ((1)O2) plays a key role when using photodynamic therapy to treat skin fibrosis disease with Hypocrellin B (HB).
authors.affiliation: Key Laboratory of Natural Pharmaceutical & Chemical Biology of Yunnan Province, Honghe University, Mengzi, Yunnan, Province, P. R. China.|School of science, Honghe University, Mengzi, Yunnan, Province, P. R. China.
authors.forename: Heping
authors.initials: H
authors.lastname: Yan
authors.affiliation: Key Laboratory of Natural Pharmaceutical & Chemical Biology of Yunnan Province, Honghe University, Mengzi, Yunnan, Province, P. R. China.|School of science, Honghe University, Mengzi, Yunnan, Province, P. R. China.
authors.forename: Yashun
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Key Laboratory of Natural Pharmaceutical & Chemical Biology of Yunnan Province, Honghe University, Mengzi, Yunnan, Province, P. R. China. zhangjucheng@163.com.|School of science, Honghe University, Mengzi, Yunnan, Province, P. R. China. zhangjucheng@163.com.
authors.forename: Jucheng
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Natural Pharmaceutical & Chemical Biology of Yunnan Province, Honghe University, Mengzi, Yunnan, Province, P. R. China.|School of science, Honghe University, Mengzi, Yunnan, Province, P. R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: Key Laboratory of Natural Pharmaceutical & Chemical Biology of Yunnan Province, Honghe University, Mengzi, Yunnan, Province, P. R. China.|School of science, Honghe University, Mengzi, Yunnan, Province, P. R. China.
authors.forename: Rui
authors.initials: R
authors.lastname: Chen
mesh_terms: D000596:Amino Acids / Q000737:chemistry* / Q000528:radiation effects; D024042:Collagen Type I / Q000737:chemistry* / Q000528:radiation effects; D005355:Fibrosis; D005780:Gelatin / Q000737:chemistry* / Q000528:radiation effects; D006801:Humans; D017665:Hydroxyl Radical / Q000737:chemistry; D010778:Photochemotherapy / Q000379:methods*; D010782:Photolysis; D017319:Photosensitizing Agents / Q000737:chemistry* / Q000494:pharmacology; D059748:Proteolysis; D026082:Singlet Oxygen / Q000737:chemistry*; D012867:Skin / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D012871:Skin Diseases / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D013050:Spectrometry, Fluorescence
chemical_list: D000596:Amino Acids; D024042:Collagen Type I; D017319:Photosensitizing Agents; D026082:Singlet Oxygen; D017665:Hydroxyl Radical; C015484:pyridinoline; D005780:Gelatin
keywords: Fibrotic skin diseases; Free radical; Hyporellin B; Photodynamic therapy; Pyridinoline cross-link