[Time course of gene expression of gamma-glutamylcysteine synthetase subunit and Nrf2 in brain tissues of rats exposed by deltamethrin].
OBJECTIVE
To investigate the time course of mRNA expression of gamma- glutamylcysteine synthetase light (GCSl) and heavy subunit (GCSh), as well as protein expression of both GCSh and NF-E2 related factor 2 (Nrf2) in cerebral cortex and hippocampus in rats exposed at single dose of deltamethrin (DM).


METHODS
Wistar male rats were exposed at single dose of DM (12.50 mg/kg bw) with i.p. At various time points of post-exposure, the rats were sacrificed at indicated time, then their cerebral cortex and hippocampus were isolated. The relative amount of mRNA expression of these genes was measured by the method of reverse transcription polymerase chain reaction (RT-PCR). The protein level was detected by the method of immunohistochemistry and image analysis system.


RESULTS
(1) At 5 and 48h after DM exposure, GCSh mRNA relative levels in cerebral cortex in rats were significantly decreased to 83.9% and 86.0% of mRNA level of corresponding tissue of control group at Oh, respectively (P < 0.05). At 5, 24 and 48h after DM exposure, transcriptional factors Nrf2 mRNA relative levels were more higher than those of both control and 72 h group and increased to 146.4%, 145.2% and 147.9% of those of control group at Oh,respectively (P < 0.05). (2) At 5 and 48h after DM exposure, GCSh mRNA relative levels in hippocampus were significantly increased to 118.4% and 118.4% of those of control group at 0h, respectively (P < 0.05). At 5h after DM exposure, GCSl mRNA relative levels in hippocampus were more higher than those of control,24h and 48h group and increased to 121.4% of those of control group at Oh (P < 0.05).


CONCLUSIONS
After single dose of DM exposure, there are up-regulation of mRNA expression of both GCSh and GCSl gene in rats hippocampus, down-regulation of mRNA expression of GCSh gene and up-regulation of mRNA expression of Nrf2. gene in rats cerebral cortex under the experimental condition.
Li
Huang-yuan
HY
Department of Health Toxicology, MOE Key Lab of Enviornment and health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
Shi
Nian
N
Zhong
Yu-fang
YF
Dai
Zhong-hua
ZH
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism; D005721:Glutamate-Cysteine Ligase / Q000235:genetics / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism; D007306:Insecticides / Q000633:toxicity; D008297:Male; D051267:NF-E2-Related Factor 2 / Q000235:genetics / Q000378:metabolism*; D009570:Nitriles / Q000633:toxicity*; D011722:Pyrethrins / Q000633:toxicity*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D007306:Insecticides; D051267:NF-E2-Related Factor 2; C495637:Nfe2l2 protein, rat; D009570:Nitriles; D011722:Pyrethrins; D012333:RNA, Messenger; C017180:decamethrin; D005721:Glutamate-Cysteine Ligase