bifenthrin and Body-Weight

Topics: Aging; Animals; Antioxidants; Apoptosis; Biological Transport; Biomarkers; Biphenyl Compounds; Body Weight; DNA Fragmentation; Gene Expression Regulation; Male; Malondialdehyde; Mice; MicroRNAs; Nitric Oxide; Organ Size; Picrates; Protective Agents; Protein Carbonylation; Pyrethrins; Reactive Oxygen Species; Reproduction; RNA, Messenger; Spermatogenesis; Spermatozoa; Spirulina; Testis; Testosterone; Transcription, Genetic

Bifenthrin (BF), as a chiral pyrethroid, is widely used to control field and household pests in China. At present, the commercial BF is a mixed compound containing cis isomers (cis-BF) including two enantiomers of 1R-cis-BF and 1S-cis-BF. In the present study, the two individual cis-BF enantiomers were separated by a preparative supercritical fluid chromatography. Then, four week-old adolescent male ICR mice were orally administered 1R-cis-BF and 1S-cis-BF separately daily for 3 weeks at doses of 0, 7.5 and 15 mg/kg/day, respectively. Results showed that the transcription status of some genes involved in cholesterol synthesis and transport as well as testosterone (T) synthesis in the testes were influenced by cis-BF enantiomers. Especially, we observed that the transcription status of key genes on the pathway of T synthesis including cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc) and cytochrome P450 17α-hydroxysteroid dehydrogenase (P45017α)) were selectively altered in the testis of mice when treated with 1S-cis-BF, suggesting that it is the possible reason to explain why the lower serum T concentration in 1S-cis-BF treated group. Taken together, it concluded that both of the cis-BF enantiomers have the endocrine disruption activities, while 1S-cis-BF was higher than 1R-cis-BF in mice when exposed during the puberty. The data was helpful to understand the toxicity of cis-BF in mammals under enantiomeric level.

Topics: Animals; Body Weight; Cholesterol Side-Chain Cleavage Enzyme; Endocrine Disruptors; Enzyme-Linked Immunosorbent Assay; Gene Expression Regulation; Hydroxysteroid Dehydrogenases; Insecticides; Male; Mice; Mice, Inbred ICR; Pyrethrins; Stereoisomerism; Testis; Testosterone

To study the potential endocrine disrupting effects of bifenthrin (BIF) by using uterotrophic assay and Hershberger assay.. In uterotrophic assay, 60 female SD rats were randomly divided into 6 groups, 10 rats per group. Rats in bifenthrin-treated groups were given different doses of bifenthrin (1.47, 4.41 and 13.23 mg/kg BW by gavage for 3 consecutive days). Rats in negative control groups were given corn oil by gavage. Rats in ethinyl estradiol (EE) oral positive control groups were given EE 1.0 microg/kg BW by gavage. Rats in EE injected positive groups were given 0.6 microg/kg BW EE by subcutaneously injection while given corn oil by gavage. At necropsy, the wet and blotted uteri were weighed. The relative uteri weights were calculated, and the histology of uteri was observed. In Hershberger assay, 60 castrated male SD rats were randomly divided into 6 groups, with 10 rats in each group. Rats in BIF-treated groups were given different doses of BIF (1.4, 4.2 and 12.6 mg/kg BW) by gavage. Flutamide (3.0 mg/kg BW) were given to animals in the positive control group by gavage. Rats in the negative control group and testosterone propionate group were given corn oil by gavage for 10 consecutive days. Rats in all groups except the negative control group were also treated with testosterone propionate (TP, 0.2 mg/kg BW) by subcutaneous injection. At necropsy, ventral prostate (VP), seminal vesicle plus fluids and coagulating glands (SVCG), levator ani-bulbocavernosus muscle (LABC), paired Cowper's glands (COW) and the glands penis (GP), liver, kidneys, adrenals were weighed. Serum triiodothyronine (T3) and thyroxine (T4) were determined.. In uterotrophic assay, compared with the negative control group, the mean relative wet weight and relative blotted weight of uterine were increased significantly in the female rats given by BIF at 13.23 mg/kg BW for 3 days (P < 0.05). BIF resulted in a significant increase of epithelial cell heights of uteri at 4.41 and 13.23 mg/kg BW, as compared with control group. In Hershberger assay, compared with the TP group, mean absolute weight and relative weight of VP and LABC in BIF high dose group were significant decreased. Moreover, total T3 and T4 level were decreased also (P < 0.05).. Uterotrophic assay and Hershberger assay used in this study showed that BIF may have endocrine disrupting properties.

Topics: Adrenal Glands; Androgen Antagonists; Animals; Body Weight; Endocrine Disruptors; Female; Humans; Liver; Male; Organ Size; Pyrethrins; Rats; Testosterone Propionate; Thyroxine; Triiodothyronine; Uterus