title: Downregulation of TLR4 and 7 mRNA expression levels in broiler's spleen caused by diets supplemented with nickel chloride.
abstract: Toll-like receptors (TLRs) are important immune receptors in discriminating self from nonself and in initiating the innate and adaptive immune response. TLR4 and TLR7 have been proven to be highly expressed in chicken's spleen. Thus, this study was to evaluate the TLR4 and TLR7 messenger RNA (mRNA) expression levels in the spleen of broilers fed diets supplemented with nickel chloride (NiCl2) using the methods of quantitative real-time PCR (qRT-PCR). Two hundred forty-one-day-old avian broilers were equally divided into 4 groups and fed on a corn-soybean basal diet as control diet or the same basal diet supplemented with 300, 600, and 900 mg/kg of NiCl2 for 42 days. Results showed that TLR4 and TLR7 mRNA expression levels in the spleen were lower (P < 0.05 or P < 0.01) in the 300, 600, and 900 mg/kg groups than those in the control group. It was concluded that dietary NiCl2 in excess of 300 mg/kg could lower TLR4 and TLR7 mRNA expression levels in the spleen of broilers, implying that NiCl2 could impair the innate and adaptive immunity in spleen by injuring immunocytes and/or decreasing the content of cytokines through TLRs.
authors.affiliation: Key Laboratory of Animal Diseases and Environmental Hazards of Sichuan Province, Sichuan Agricultural University, Ya'an, Sichuan, China, 625014.
authors.forename: Jianying
authors.initials: J
authors.lastname: Huang
authors.forename: Hengmin
authors.initials: H
authors.lastname: Cui
authors.forename: Xi
authors.initials: X
authors.lastname: Peng
authors.forename: Jing
authors.initials: J
authors.lastname: Fang
authors.forename: Zhicai
authors.initials: Z
authors.lastname: Zuo
authors.forename: Junliang
authors.initials: J
authors.lastname: Deng
authors.forename: Xun
authors.initials: X
authors.lastname: Wang
authors.forename: Bangyuan
authors.initials: B
authors.lastname: Wu
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D030161:Avian Proteins / Q000235:genetics*; D002645:Chickens; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects; D015870:Gene Expression / Q000187:drug effects; D009532:Nickel / Q000008:administration & dosage / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013154:Spleen / Q000378:metabolism*; D013997:Time Factors; D051197:Toll-Like Receptor 4 / Q000235:genetics*; D051199:Toll-Like Receptor 7 / Q000235:genetics*
chemical_list: D030161:Avian Proteins; D012333:RNA, Messenger; D051197:Toll-Like Receptor 4; D051199:Toll-Like Receptor 7; C022838:nickel chloride; D009532:Nickel