Effects Of Fluoride On Sperm Chemotaxis And Its Meachanism Study In Male Mice

[Objective] Reproductive process covers lots of procedures, including capacitation, hyperactivation, chemotaxis and the acrosome reaction. Everyone plays an important role in the success of fertilization. Although there have lots of studies about the toxic effects of fluoride on male reproduction, the influence of fluoride on sperm chemotaxis is little known. This study is to detect whether fluoride would affect sperm chemotaxis, and then to reveal the underling mechanisms of fluoride toxicity in sperm chemotaxis if it does.[Method]260healthy Kunming male mice(8weeks old) were randomly divided into4groups and exposed to50,100,150mg NaF/L in their drinking water for8weeks. At the end of the exposure periods, sperm chemotaxis was measured using a microchannel-based device. Ca2+concentration, AC content and mRNA expression of ACIII, ACVIII, Golf alpha, CatSper1,CatSper2were determined to elucidate the possible molecular mechanisms.[Results]1. After8weeks exposure, there were no significant difference in body weight and major organs coefficient were observed between NaF treatment groups and control groups. In the sperm quality assessment,100mg NaF/L treatment group and150mg NaF/L treatment group showed significant difference compared with control group.Besides,HE staining photos showed that high does fluoride would demage the structure of testis.2. In the sperm chemotaxis test,50mg NaF/L treatment group compared to control group had no statistical differnece, however,100mg NaF/L treatment group and150mg NaF/L treatment group showed a significant decent compared with control group, and the significant decreased by32%and45%respectively.3. The result of sperm intracellular Ca2+concentration test showed that100and150mg NaF/L groups were significantly decreased the sperm intracellular Ca2+concentration, and the significant decreased by26.8%and45.3%respectively. However, there was no statistical difference was observed between the low treatment group and control group.4. The result of sperm AC ELISA test showed that NaF treatment had a adversely effect on mice sperm AC content. Compared with control group, the middle and higher treatment groups significantly decreased the AC content. Though the50mg NaF/L treatment group detected no statistical difference, it showed decreased compareing to control group.5. According to the results of QRT-PCR, level of CatSperl mRNA was decreased significantly in the middle and higher treatment groups, and decreased by25.8%and31.5%respectively. Whereas, The other mRNA of target genes detected no statistical difference.[Conclusion] Taken together, our study showed that fluoride would reduced the ratio of chemtactic sperm in mice by administrating with100and150mg NaF/L in drinking water for8weeks. The toxicity mechanism may include the decent of sperm intracellular Ca2+concentration, AC content, and mRNA expression of CatSperl. However,Fluoride induced mouse sperm chemotaxis descending would be one reason of fluoride induced male reproduction damage。...