title: Alkannin, HSP70 inducer, protects against UVB-induced apoptosis in human keratinocytes.
abstract: Alkannin is an active constituent from the root extract of Alkanna tinctoria of the Boraginaceae family and it may have utility as a heat shock protein 70 (HSP70) inducer in living organisms. Here, the effects of alkannin-induced HSP70 on ultraviolet (UV) B (40 mJ/cm(2))-induced apoptosis were investigated in human keratinocyte HaCaT cells. Pretreatment of cells with alkannin (1 µM) caused significant inhibition of UVB-induced apoptosis and caspase-3 cleavage. On the other hand, the addition of KNK437 (HSP70 inhibitor) reversed the action of alkannin increasing UVB-induced apoptosis in a dose-dependent manner. In addition, differences in gene expression associated with the suppression of UVB-induced apoptosis in the presence of alkannin were investigated using Gene Chip assay. Our results indicate that alkannin suppresses UVB-induced apoptosis through the induction of HSP70 in human keratinocytes, and therefore, we suggest the usefulness of using alkannin as an antiaging agent.
authors.affiliation: Department of Dermatology, Life Science Research Center, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Yoshihisa
authors.forename: Mariame Ali
authors.initials: MA
authors.lastname: Hassan
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Furusawa
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Tabuchi
authors.forename: Takashi
authors.initials: T
authors.lastname: Kondo
authors.forename: Tadamichi
authors.initials: T
authors.lastname: Shimizu
mesh_terms: D000704:Analysis of Variance; D017209:Apoptosis / Q000187:drug effects* / Q000528:radiation effects; D001559:Benzhydryl Compounds; D015153:Blotting, Western; D053148:Caspase 3 / Q000378:metabolism; D002460:Cell Line; D053938:DNA Fragmentation / Q000187:drug effects / Q000528:radiation effects; D018840:HSP70 Heat-Shock Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D015603:Keratinocytes / Q000187:drug effects* / Q000528:radiation effects; D009285:Naphthoquinones / Q000378:metabolism / Q000494:pharmacology*; D020411:Oligonucleotide Array Sequence Analysis; D011760:Pyrrolidinones; D060888:Real-Time Polymerase Chain Reaction; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D001559:Benzhydryl Compounds; D018840:HSP70 Heat-Shock Proteins; C410027:KNK 437; D009285:Naphthoquinones; D011760:Pyrrolidinones; C018204:alkannin; D053148:Caspase 3