Suppression of cadmium-induced JNK/p38 activation and HSP70 family gene expression by LL-Z1640-2 in NIH3T3 cells.
When NIH3T3 cells were exposed to CdCl(2), the three major mitogen-activated protein kinases (MAPKs), extracellular signal-regulated protein kinase (ERK), c-Jun NH(2)-terminal kinase (JNK), and p38, were phosphorylated in a time (1-9 h)- and dose (1-20 microM)-dependent manner. Treatment with a macrocyclic nonaketide compound, LL-Z1640-2 (10-100 ng/ml), suppressed the phosphorylation of MAPKs without affecting the total protein level in cells exposed to 10 microM CdCl(2) for 6 h. CdCl(2)-induced phosphorylation of c-Jun on Ser63 and that on Ser73, and resultant accumulation of total c-Jun protein were also suppressed by LL-Z1640-2 treatment. The in vitro kinase assays also showed significant inhibitory effects of LL-Z1640-2 (at 10 or 25 ng/ml) on JNK and p38 but less markedly. In contrast to JNK and p38, ERK activity was inhibited moderately only at 50 or 100 ng/ml LL-Z1640-2. On the other hand, other JNK inhibitors, SP600125 and L-JNKI1, failed to suppress CdCl(2)-induced activation of the JNK pathway. Among the mouse stress response genes upregulated in response to CdCl(2) exposure, the expressions of hsp68 (encoding for heat shock 70 kDa protein 1; Hsp70-1) and grp78 (encoding for 78 kDa glucose-regulated protein; Grp78) genes were suppressed by treatment with 25 ng/ml LL-Z1640-2. Thus, LL-Z1640-2 could suppress CdCl(2)-induced activation of JNK/p38 pathways and expression of HSP70 family genes in NIH3T3 cells. LL-Z1640-2 seems to be useful to analyze functions of toxic metal-induced JNK/p38 activation.
Sugisawa
Nobusuke
N
Department of Environmental Toxicology, University of Occupational and Environmental Health, Yahatanishi, Kitakyushu 807-8555, Japan.
Matsuoka
Masato
M
Okuno
Takeo
T
Igisu
Hideki
H
D000818:Animals; D000873:Anthracenes / Q000494:pharmacology; D015153:Blotting, Western; D019256:Cadmium Chloride / Q000037:antagonists & inhibitors* / Q000633:toxicity; D004347:Drug Interactions; D000091342:Endoplasmic Reticulum Chaperone BiP; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects; D018840:HSP70 Heat-Shock Proteins / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases; D007783:Lactones / Q000494:pharmacology*; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D041681:NIH 3T3 Cells; D020411:Oligonucleotide Array Sequence Analysis; D010766:Phosphorylation / Q000187:drug effects; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D048051:p38 Mitogen-Activated Protein Kinases
D000873:Anthracenes; D000091342:Endoplasmic Reticulum Chaperone BiP; D004791:Enzyme Inhibitors; D018840:HSP70 Heat-Shock Proteins; C000717248:Hspa5 protein, mouse; C118715:LL Z1640-2; D007783:Lactones; D012333:RNA, Messenger; C432165:pyrazolanthrone; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D019256:Cadmium Chloride