Studies On The Antagonism Of Selenium To The Fluorine Immunotoxicity In Chicken

In this paper, 8-day-old chicken (n=180) were used as experimental animals, certain concentration of sodium fluoride and sodium selenium were added in the basic diets . Immunotoxicity model caused by subchronic-fluorine toxicities and antagonism model of selenium to fluorine toxicities were duplicated. The sub chronic-fluorine toxicities and antagonism of selenium to fluorine toxicities were deeply studied through observing clinical symptom, pathological changes of immunity tissues, detecting anti-oxidative function, apoptosis,T-Cell subset, the expression level of p53 and Cu-Zn-SOD mRNA in immunity tissues. The results showed as follows:1. The experimental results revealed that fluorine affected the anti-oxidative function of chicken. Activity of SOD and GSH-Px decreased during mid and late period in serum and immunity tissues while the content of MDA increased all through the experimental period, which constituted pathological basis of fluorine damaging the host body. The fact that supplementing selenium may decrease fluorine damage indicated selenium can antagonize the toxicities of fluorine to anti-oxidative system in chicken.2.Fluorine decreased the content of CD4+,CD4+/CD8+ in serum and immunity tissues, which could be inhibited by selenium. This indicated selenium can decrease the immunotoxicity of fluorine and furthermore increase immunological function of fluorisis-chicken.3. The results of TUNEL and ultra structure observation showed that fluorine toxicities caused apoptosis in immunity tissues of chicken, adding selenium relieved the damaging effect of fluorine. Fluorine could make the damage of mitochondrion and selenium decreased the damaging effect of fluorine on mitochondrion. This indicated selenium can antagonize the apoptosis of testicular cell induced by fluorine.4. The effect of fluorine on Cu-Zn-SOD mRNA expression was detected by QT-PCR. It revealed that fluorine can increase the mRNA expression of Cu-Zn-SOD and furthermore decrease the activity of SOD of immunity tissues. Selenium can antagonize the effect of fluorine toxicities by decrease the mRNA expression of Cu-Zn-SOD and furthermore antagonize the toxicities of fluorine to anti-oxidative system in chicken..5. The effect of fluorine on p53 mRNA expression was detected by PT-PCR. It revealed that fluorine can increase the mRNA expression of p53and furthermore induce apoptosis of immunocytes. Selenium can antagonize the effect of fluorine toxicities by decrease the mRNA expression of p53 and furthermore antagonize apoptosis of immunocytes in chicken caused by fluorine.Our study discussed the selenium antagonism to fluorine toxicities in chicken with organ, cellular and molecular view. Results revealed that selenium can antagonize the fluorine toxicities which presented as increasing the content of CD4+,CD4+/CD8+ and improving damaged anti-oxidative system,reducing oxidative stress, decreasing apoptosis of immunocytes and changing the expression of Cu-Zn-SOD and apoptosis-related gene p53. The mechanism of selenium antagonism to fluorine toxicities in chicken were illuminated. This research was significant to offer the theory for protection and treatment of fluorine toxicities in livestock, enriching toxicology and Comparative Medicine. And, it is also meaningful to ensure the healthy development of graziery, to protect wild fowl and to keep the ecological balance.