Variations in the mRNA expression of inflammatory mediators, markers of differentiation and lipid-metabolizing enzymes caused by sodium lauryl sulphate in cultured human keratinocytes.
Detergents are well known irritants. Effects of the detergent sodium lauryl sulphate (SLS) on cell toxicity using the XTT assay and mRNA expression of inflammatory mediators, markers of keratinocyte differentiation and enzymes synthesizing barrier lipids using real-time PCR were studied in cultured differentiated keratinocytes. After exposure for 24 h to SLS concentrations at 0.002% or above, toxic effects were observed. When a lower SLS concentration (0.00075%) was used the mRNA expression of inflammatory mediators peaked around 4-8 h. The expression of enzymes involved in the synthesis of cholesterol, fatty acids and ceramides and markers of keratinocyte differentiation also increased but after 24 h. In cells exposed to 0.000125-0.0015% SLS, a concentration-dependent induction of the expression of inflammatory mediators was found after 4 h. Similar changes were found after 24 h for involucrin and enzymes involved in ceramide synthesis. The mRNA expression of HMG-CoA synthase and reductase, long-chain acyl-CoA synthase and transglutaminase also peaked after 24 h, but maximal induction was observed already at 0.00075% SLS. In conclusion, SLS induces an inflammatory response in keratinocytes and alters the mRNA expression of important barrier lipid enzymes and markers of keratinocyte differentiation, of possible importance for the irritant properties of SLS.
Törmä
Hans
H
Department of Medical Sciences, Uppsala University, Dermatology and Venereology, Akademiska sjukhuset, SE-751 85 Uppsala, Sweden. hans.torma@medsci.uu.se
Geijer
Sophia
S
Gester
Therése
T
Alpholm
Karin
K
Berne
Berit
B
Lindberg
Magnus
M
D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D016207:Cytokines / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004798:Enzymes / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D007509:Irritants / Q000633:toxicity*; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism; D050356:Lipid Metabolism / Q000187:drug effects / Q000502:physiology; D011498:Protein Precursors / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*; D012967:Sodium Dodecyl Sulfate / Q000633:toxicity*; D013501:Surface-Active Agents / Q000633:toxicity*
D016207:Cytokines; D004798:Enzymes; D007509:Irritants; D011498:Protein Precursors; D012333:RNA, Messenger; D013501:Surface-Active Agents; D012967:Sodium Dodecyl Sulfate