Yunchang Zhang1, Hai Jia1, Yuhang Jin1, Ning Liu1, Jingqing Chen1, Ying Yang1, Zhaolai Dai1, Chao Wang2, Guoyao Wu1,3, Zhenlong Wu1,4. 1. State Key Laboratory of Animal Nutrition, Department of Animal Nutrition and Feed Science, China Agricultural University, Beijing 100193, China. 2. State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China. 3. Department of Animal Science, Texas A&M University, College Station, TX 77843, USA. 4. Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100193, China.
Abstract
BACKGROUND: Liver dysfunction impairs immunological homeostasis. Glycine (Gly) has been reported to have antioxidative and anti-inflammatory effects and to regulate apoptosis in various models. OBJECTIVES: The aim of the present study was to determine whether Gly could attenuate LPS-induced liver injury. METHODS: In Experiment 1, 48 6-week-old male C57BL/6 mice were randomly assigned into one of 4 groups: CON (control), GLY [orally administered Gly, 5 g · kg body weight (BW)-1 · d-1 for 6 d], LPS (5 mg/kg BW, intraperitoneally administered), and GLY + LPS (Gly supplementation, and on day 7 LPS treatment). In Experiment 2, mice were untreated, pretreated with Gly as above, or pretreated with Gly + l-buthionine sulfoximine (BSO) (0.5 g/kg BW, intraperitoneally administered every other day) for 6 d. On day 7, mice were injected with LPS as above. Histological alterations, activities of antioxidative enzymes, apoptosis, and immune cell infiltration were analyzed. RESULTS: In Experiment 1, compared with CON, LPS administration resulted in increased karyolysis and karyopyknosis in the liver by 8- to 10-fold, enhanced serum activities of alanine transaminase (ALT), aspartate transaminase (AST), and lactate dehydrogenase (LDH) by 1- to 1.8-fold, and increased hepatic apoptosis by 5.5-fold. Furthermore, LPS exposure resulted in increased infiltration of macrophages and neutrophils in the liver by 3.2- to 7.5-fold, elevated hepatic concentrations of malondialdehyde and hydrogen peroxide (H2O2), and elevated myeloperoxidase (MPO) activity by 1.5- to 6.3-fold. In Experiment 2, compared with the LPS group, mice in the GLY + LPS group had fewer histological alterations (68.5%-75.9%); lower serum ALT, AST, and LDH activities (24.3%-64.7%); and lower hepatic malondialdehyde and H2O2 concentrations (46.1%-80.2%), lower MPO activity (39.2%), immune cell infiltration (52.3%-85.3%), and apoptosis (69.6%), which were abrogated by BSO. Compared with the GLY + LPS group, mice in the GLY + BSO + LPS group had lower hepatic activities of catalase, superoxide dismutase, and glutathione peroxidase by 33.5%-48.5%; increased activation of NF-κB by 2.3-fold; and impaired nuclear factor (erythroid-derived 2)-like 2 signaling by 38.9%. CONCLUSIONS: Gly is a functional amino acid with an ability to protect the liver against LPS-induced injury in mice.
BACKGROUND:Liver dysfunction impairs immunological homeostasis. Glycine (Gly) has been reported to have antioxidative and anti-inflammatory effects and to regulate apoptosis in various models. OBJECTIVES: The aim of the present study was to determine whether Gly could attenuate LPS-induced liver injury. METHODS: In Experiment 1, 48 6-week-old male C57BL/6 mice were randomly assigned into one of 4 groups: CON (control), GLY [orally administered Gly, 5 g · kg body weight (BW)-1 · d-1 for 6 d], LPS (5 mg/kg BW, intraperitoneally administered), and GLY + LPS (Gly supplementation, and on day 7 LPS treatment). In Experiment 2, mice were untreated, pretreated with Gly as above, or pretreated with Gly + l-buthionine sulfoximine (BSO) (0.5 g/kg BW, intraperitoneally administered every other day) for 6 d. On day 7, mice were injected with LPS as above. Histological alterations, activities of antioxidative enzymes, apoptosis, and immune cell infiltration were analyzed. RESULTS: In Experiment 1, compared with CON, LPS administration resulted in increased karyolysis and karyopyknosis in the liver by 8- to 10-fold, enhanced serum activities of alanine transaminase (ALT), aspartate transaminase (AST), and lactate dehydrogenase (LDH) by 1- to 1.8-fold, and increased hepatic apoptosis by 5.5-fold. Furthermore, LPS exposure resulted in increased infiltration of macrophages and neutrophils in the liver by 3.2- to 7.5-fold, elevated hepatic concentrations of malondialdehyde and hydrogen peroxide (H2O2), and elevated myeloperoxidase (MPO) activity by 1.5- to 6.3-fold. In Experiment 2, compared with the LPS group, mice in the GLY + LPS group had fewer histological alterations (68.5%-75.9%); lower serum ALT, AST, and LDH activities (24.3%-64.7%); and lower hepatic malondialdehyde and H2O2 concentrations (46.1%-80.2%), lower MPO activity (39.2%), immune cell infiltration (52.3%-85.3%), and apoptosis (69.6%), which were abrogated by BSO. Compared with the GLY + LPS group, mice in the GLY + BSO + LPS group had lower hepatic activities of catalase, superoxide dismutase, and glutathione peroxidase by 33.5%-48.5%; increased activation of NF-κB by 2.3-fold; and impaired nuclear factor (erythroid-derived 2)-like 2 signaling by 38.9%. CONCLUSIONS:Gly is a functional amino acid with an ability to protect the liver against LPS-induced injury in mice.
Authors: Fernando Gómez-Chávez; Carlos Cedillo-Peláez; Luis A Zapi-Colín; Guadalupe Gutiérrez-González; Isaí Martínez-Torres; Humberto Peralta; Leslie Chavez-Galan; Erick D Avila-Calderón; Araceli Contreras-Rodríguez; Yaneth Bartolo-Aguilar; Sandra Rodríguez-Martínez; Mario E Cancino-Diaz; Juan C Cancino-Diaz Journal: Int J Mol Sci Date: 2021-12-02 Impact factor: 5.923
Authors: Yunchang Zhang; Xiaoshi Ma; Da Jiang; Jingqing Chen; Hai Jia; Zhenlong Wu; In Ho Kim; Ying Yang Journal: Nutrients Date: 2020-02-26 Impact factor: 5.717