title: Inhibitive effects of nickel chloride (NiCl₂) on thymocytes.
abstract: The purpose of this study was to define the inhibitive effects of dietary nickel chloride (NiCl2) on thymocytes in broilers fed on diets supplemented with 0, 300, 600, and 900 mg/kg of NiCl2 for 42 days. We examined the changes of cell cycle phase, percentages of apoptotic cells, T cell subsets, cytokines, and mRNA expression of apoptotic proteins (bcl-2, bax, and caspase-3) in thymocytes by flow cytometry and quantitative real-time polymerase chain reaction (qRT-PCR). In the NiCl2-treated broilers, the percentages of thymocytes in G0/G1 phase were increased, whereas thymocytes in the S phase and the proliferation index were decreased. The percentages of apoptotic thymocytes were increased. Also, the mRNA expression levels of bax and caspase-3 were increased, and mRNA expression levels of bcl-2 were decreased. The percentages of CD3(+), CD3(+)CD4(+), and CD3(+)CD8(+) T lymphocytes in the thymus and peripheral blood were diminished. Concurrently, thymic cytokine (interleukin-1 beta (IL-1β), interleukin-2 (IL-2), interleukin-10 (IL-10), interleukin-12 p35 subunit (IL-12p35), interleukin-12 p40 subunit (IL-12p40), interleukin-21 (IL-21), interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), thymosin β4, thymosin β10, and thymosin β15) mRNA expression levels were decreased. The abovementioned results showed that dietary NiCl2 in excess of 300 mg/kg inhibited thymocyte growth by arresting cell cycle, increasing apoptosis percentage, altering apoptotic protein mRNA expression levels, and downregulating cytokine expression levels.
authors.affiliation: Key Laboratory of Animal Diseases and Environmental Hazards of Sichuan Province, Sichuan Agricultural University, Ya'an, 625014, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Tang
authors.forename: Hongrui
authors.initials: H
authors.lastname: Guo
authors.forename: Jie
authors.initials: J
authors.lastname: Deng
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: Xun
authors.initials: X
authors.lastname: Wang
authors.forename: Bangyuan
authors.initials: B
authors.lastname: Wu
authors.forename: Jian
authors.initials: J
authors.lastname: Li
authors.forename: Shuang
authors.initials: S
authors.lastname: Yin
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000187:drug effects* / Q000235:genetics; D051017:Apoptosis Regulatory Proteins / Q000235:genetics / Q000378:metabolism*; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects* / Q000235:genetics; D002645:Chickens; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D019587:Dietary Supplements; D005434:Flow Cytometry; D015870:Gene Expression / Q000187:drug effects; D009532:Nickel / Q000008:administration & dosage / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016176:T-Lymphocyte Subsets / Q000187:drug effects / Q000378:metabolism; D060168:Thymocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D013997:Time Factors; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: D051017:Apoptosis Regulatory Proteins; D016207:Cytokines; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; C022838:nickel chloride; D009532:Nickel; D053148:Caspase 3