Study on Immune Organs injuries Mechanism of Selenium Deficiency in Chicken.pdf

1、Nutritional trace element selenium(Se)is a valuable component for the normal immune function in various life forms.Selenoproteins and Se play important roles in the immune system.Se is necessary for the immune system in

2、chicken and mediates its physiological functions through selenoproteins.Cytokines are soluble,low molecular weight polypeptides and glycopeptides produced by a broad range of cell types of haematopoietic and nonhaematopo

3、ietic origin that have suppressive or enhansive effects on cellular proliferation,differentiation,activation,and motility.Heat shock proteins(Hsps)are present nearly in all species with their conserved nature,and Hsps ar

4、e used as biomarkers of various stresses condition in animals as well as birds.Autophagy is a process which exerts effect of targeted component and its action in particular cells and system.Selenoprotein,cytokine,Hsps,au

5、tophagy related genes and ultra structures in the immune system of mammals are sensitive to dietary Se levels;however,little is known about the expression of selenoproteins,Hsps mRNAs,Hsp proteins level,mRNAs expression

6、of autophagy-related genes,protein levels of autophagy-related genes,effects on cytokines,and on internal structures of in the chicken spleen,bursa of Fabriciuos and thymus with Se deficiency.We assessed selenoproteins m

7、RNAs expression of(Txnrd1,Txnrd2,Txnrd3,Dio1,Dio2,Dio3,GPx1,GPx2,GPx3,Gpx4,Sepp1,Selo,Sep15,Sepx1,Sels,Seli,Selu,Selh,and SPS2),Hsps mRNAs expression of(Hsp27,Hsp40,Hsp60,Hsp70,and Hsp90),Hsp proteins level of(Hsp40,Hsp6

8、0,Hsp70,and Hsp90),autophagy-related genes mRNAs expression of(LC3-Ⅰ,LC3-Ⅱ,Beclin1,Dynein,ATG5,TOR1),protein levels of autophagy related genes(LC3-Ⅱ,Beclin1,Dynein),cytokine content(IL-2,IL-6,IL-8,IL-10,IL-17,IL-1β,IFN-α

9、,IFN-β,IFN-γand TNF-α)and change in structural integrity in the tissues in the chicken spleen,bursa of Fabricius and thymus in this study.The animals were randomly assigned into two groups as follows:the Se-deficient gro

10、up(L group)was fed a diet containing0.033mg Se/Kg,and the control group was fed the same basal diet supplemented with Se at0.15mg/kg(sodium selenite).Real-time qPCR was used to investigate the expression level of selenop

11、roteins,Hsps and autophagy-related genes on days15,25,35,45,and55,protein level of heat shock protein and autophagy genes were check through western blot analysis on days35,45and55,ELISA was used to evaluate the cytokine

12、 content on days15,35,and55,an electron microscope was used to observed the structural change in chicken immune organs.
　　The result revealed that selenoprotein messenger RNA(mRNA)levels of Txnrd1,Txnrd2,Txnrd3,Dio1,D

13、io2,Dio3,GPx1,GPx2,GPx3,Gpx4,Sepp1,Selo,Sep15,Sepx1,Sels,Seli,Selu,Selh,and SPS2were all significantly decreased in the Se deficiency group compared to the control group in spleen,bursa of Fabricius and thymus of chicken

14、.
　　Cytokines study showed that in spleen IL-2,IL-6,IL-17,IL-1β,IFN-αwere significantly decreased and there was also significant increased in IL-8,IL-10,IFN-β,IFN-γand TNF-αin Se deficiency group.In bursa of Fabricius

15、 the IL-2,IL-6,IL-8,IL-10,IL-17,IL-1β,IFN-α,IFN-β,IFN-γwere significantly decreased,and TNF-αwas significantly increased in the Se deficiency.In thymus a significant decrease in IL-2,IL-10,IL-17,IL-1β,IFN-α,IFN-βwas obse

16、rved in the Se deficiency group,and there also a significant increase in IL-6,IL-8,IFN-γ，and TNF-αin the L group in thymus of chicken.
　　Result of Hsps messenger RNA(mRNA)levels showed that(Hsp27,Hsp40,Hsp60,Hsp70,and

17、 Hsp90)were significantly increased in spleen,bursa of Fahricius and thymus of the Se deficient group.The proteins levels of Hsps(Hsp60,Hsp70,and Hsp90)were significantly increased in spleen,bursa of Fabrieiuos and thymu

18、s of the Se deficient group.
　　Autophagy-related gene expression results showed that in spleen mRNA levels of LC3-Ⅰ,LC3-Ⅱ,Beclin1,Dynein,ATG5,TOR1were high and protein levels LC3-Ⅱ,Beclin1and Dynein was also observed

19、high in Se deficiency group as compared to control group in chicken spleen.In bursa of Fabricius as compared to the control group mRNA level of LC3-Ⅰ,LC3-Ⅱ,Beclin1,Dynein,ATG5,TOR1was increased and protein level of Becli

20、n1and Dynein were increased and LC3-2was low in Se deficiency group.In thymus as compared to the control group mRNA levels of LC3-Ⅰ,Beclin1and AGT5were high and LC3-Ⅱ,Dynein,TOR1were observed low and protein level ofBecl

21、in1was high and LC3-Ⅱand Dynein were recorded low in Se deficiency group.Further cellular morphological changes such as autophagy vacuole,autolysosome and lysosomal degradation were observed in the spleen,bursa of Fabric

22、ius and thymus of Se deficiency group.
　　In summary,Se deficiency results in significant decreased in the expression of selenoproteins,change in the cytokine,and change in autophagy-related genes.Further ultra structu

23、re in chicken immune organs showed histopathology,immuno-supersion,and increased in the Hsps participated in protective mechanism in tissues of spleen,bursa of Fabricius and thymus of Se deficiency group.Our results prov