Marked expression of glutathione S-transferase A4-4 detoxifying 4-hydroxy-2(E)-nonenal in the skin of rats irradiated by ultraviolet B-band light (UVB).
Enzyme, Western blot, and immunohistochemical analyses indicated that rat skin cytosol contained no detectable level of the homodimeric, alpha-class glutathione S-transferase (rGST) A4-4 which catalyzes the GSH conjugation of the toxic product, 4-hydroxy-2(E)-nonenal (HNE), nonenzymatically formed from n-6 polyunsaturated fatty acid residues of lipids by lipid peroxidation. Rats irradiated by single doses (4000-24,000 mJ/cm(2)) of ultraviolet B-band light (UVB, 200 mJ/cm(2)/min) markedly expressed rGSTA4-4 in the skin at a level one-fifth that of the liver in apparent specific activity toward HNE at a single dose of 24,000 mJ/cm(2). Skin rGSTA4-4 was isolated, purified to homogeneity, and identified with hepatic rGSTA4-4 by reverse-phase partition HPLC and by amino acid sequence analysis of its CNBr fission peptides. Immunohistochemistry with polyclonal antibody raised against rGSTA4-4 demonstrated the selective expression of rGSTA4-4 in epidermis and sebaceous glands localized in dermis after UVB irradiation.
Department of Drug Metabolism and Molecular Toxicology, School of Pharmacy, Tokyo University of Pharmacy and Life Science, Hachioji-shi, Tokyo, 192-0392, Japan.
A
A
Hiratsuka
H
H
Saito
K
K
Hirose
T
T
Watabe
D000447:Aldehydes / Q000378:metabolism* / Q000633:toxicity; D000818:Animals; D015153:Blotting, Western; D002851:Chromatography, High Pressure Liquid; D003600:Cytosol / Q000201:enzymology / Q000378:metabolism / Q000528:radiation effects; D015971:Gene Expression Regulation, Enzymologic / Q000528:radiation effects*; D005978:Glutathione / Q000378:metabolism; D005982:Glutathione Transferase / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D007150:Immunohistochemistry; D008658:Inactivation, Metabolic; D007527:Isoenzymes / Q000378:metabolism; D008099:Liver / Q000201:enzymology; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D017421:Sequence Analysis; D012867:Skin / Q000166:cytology / Q000201:enzymology / Q000378:metabolism / Q000528:radiation effects*; D014466:Ultraviolet Rays; D015854:Up-Regulation / Q000528:radiation effects
D000447:Aldehydes; D007527:Isoenzymes; D005982:Glutathione Transferase; D005978:Glutathione; C027576:4-hydroxy-2-nonenal