Effects of β-conglycinin on expression of TLR2/NF-κB p65 and inflammatory-related genes in head kidney of juvenile common carp Cyprinus carpio haematopterus
YIN Haicheng, HUANG Jin, JIA Feng, ZHENG Xin
College of Biological Engineering, Henan University of Technology, Zhengzhou
Abstract: A 21 d feeding trial was conducted to investigate the effects of replacement of fish meal protein with β-conglycinin in diets on the expression of TLR2/NF-κB p65, IL-1β, IL-6, TNF-α1 and IFN-γ in head kidney of juvenile common carp, Cyprinuscarpiohaematopterus.A total of 225 juvenile common carp with initial body weight of(41.00±0.12)g were divided into 5 groups with 3 replicates per group and 15 fish per replicate, and fed five isonitrogenous(protein level 38.0%)and isolipidic(lipid level 6.0%)diets formulated by replacing 0%(control group), 1.0%, 3.0%, 5.0% and 7.0% fish meal protein with β-conglycinin on the basis of the basal diet in an automatic circulating aquarium at water temperature of 25-27 ℃.The expression levels of TLR2/NF-κBp65, IL-1β, IL-6, TNF-α1 and IFN-γ gene were analyzed in head kidney of juvenile common carp fed the test diets for 1, 7, 14 d, and 21 d.The results showed that the β-conglycinin levels and the feeding time had a distinct influence on the expression levels of TLR2/NF-κBp65 and cell cytokines including IL-1β, IL-6 and TNF-α1, with a dose and time-dependent, without interaction, only the expression of IFN-γ being dose-dependent.The fish in 3.0% or more β-conglycinin groups had significantly higher relative expression levels of TLR2/NF-κBp65, IL-1β, IL-6 and TNF-α1 gene than that in fish in control group from day 1 to day 21(P<0.05).However, on the 21st day, the expression of each factor tended to be decreased compared with the fish on the 14th day.Compared with the control group, the expression levels of IL-6 and IFN-γ were increased significantly in 1.0%, 3.0% and 5.0% β-conglycinin groups during the experimental period(P<0.05).The findings indicate that β-conglycinin leads to induce the expression of TLR2/NF-κBp65, IL-1β, IL-6, and TNF-α1 in head kidney of juvenile common carp and inflammation response of fish in which the signaling pathway is involved in the expression of TLR2/NF-κBp65 and downstream inflammatory cytokine.From the result above, we postulate that β-conglycinin can cause inflammation response of fish.Therefore, it is not suitable that adding the high dosage of soybean protein in fish diets.
2020, Vol. 35 
