The Dysregulation Of Movement And Reproductive Capacity In Caenorhabditis Elegans Exposed To Triclosan During Pregnancy

Background:Endocrine disruptors(EDCs), such as Triclosan(TCS) or through binding to hormone receptors on cell signaling pathways, etc. analog or partial simulation hormones play a hormone-like or anti-hormone-like effects, disturb hormone synthesis, secretion, transport,binding, metabolism and development of children.Caenorhabditis elegans as a model animal with a short life cycle, reproduction speed, small individual,easy to train and genetic and developmental context clearly many other advantages, has been widely used in various fields of biological research. C.elegans face variety of drugs, pollutants sensitive and behavioral response patterns stable, reliable, and evaluation of contamination.Objective:To explore the effect and toxicity of Triclosan exposure on the locomotory behavior, brood size, generation time and fat accumulation in C.elegans F1generation.Methods:The model organism C.elegans were classified as control group (no Triclosan treatment), TCS treatment group1(with a100nmol/L TCS treatment), TCS treatment group2(with a1μmol/L TCS treatment), TCS treatment group3(with a10μmol/L TCS treatment), and TCS treatment group4(with a20μmol/L TCS treatment). TCS treatment was began at period L4of C.elegans cultured in100mm plates. After24hr-exposure, C.elegans were transferred into no TCS culture plates for further development. We observed the effects of TCS exposure on locomotory behavior, brood size, generation time, body length, body width and other biological indexes in C.elegans Flgeneration. We detected the triglycerides content and observed the fat accumulation of C.elegans F1generation larvae in period L4by using Sudan black B dyeing. Statistical analysis was performed by SPSS20.0software with values of p<0.05marked as statistically significant. All data are expressed as means±SD. Comparisons between groups were made with one-way analysis ofvariance(ANOVA).Results:1. Compared with the control group, the head thrashes frequency was much lower in TCS treatment groups(P<0.01), the result of one-way ANOVA showed a reduced head thrashes ability of C.elegans Fl generation in TCS treatment groups(F=62.245,P<0.01); Compared to the control group, the body bent frequency of C.elegans F1generation in TCS treatment groups was lower(P<0.01), and the result of one-way ANOVA showed that the body bent ability of C.elegans in TCS treatment groups was significantly inhibited(F=25.636, P<0.01).2. Compared with the control group, the brood sizes of the C.elegans Fl generation exposed to100nmol/L,1μmol/L,10μmol/L,20μmol/L TCS levels, were reduced by4.71%、25.60%、39.45%、58.67%, respectively. One-way ANOVA showed that the reproductive ability of the C.elegans’Fl generation was extremely affected by TCS exposure (F=461.593, P<0.01); The generation time of the C.elegans’F1generation was shortened by2.14%-5.38%in TCS treatment groups compared to the control group (P<0.01), showing a concentration dependence phenotype. ANOVA showed a statistical significance in generation time between groups(F=27.520, P<0.01).3. Compared with the control group, there was no statistical significance in body length or width of C.elegans F1generation larvae (period L4) exposed to100nmol/L,1μmol/L,10μmol/L,20μmol/L TCS levels (P>0.05).4.Microarray results were shown:the control group and TCS20μmol/Lexposure greater than2-fold difference between the two groups, small differences in the group a total of113differentially expressed genes, most of the C.elegans genes were regulation of neurodevelopmental and sports-related.Differences between selected groups of more than3-fold difference in the group of seven genes of small validate and verify the results match the microarray.Conclusion:1.The locomotory behavior, reproductive capacity of C.elegans F1generation can be severely affected by prenatal exposure to different levels of TCS, demonstrating the TCS’s reproductive toxicity and damage to neurobehavioral development.2.GO analysis and Pathway analysis showed that may be because of differences in gene expression after exposure to TCS during pregnancy can severely affected the locomotory behavior and reproductive capacity of the c.elegans Fl generation.3.The result of gene chipin differentially expressed genes, suggesting that exposure to TCS during pregnancy might be produce more long-term effects in c.elegans offspring.