Abstract #W81
Section: Physiology and Endocrinology (posters)
Session: Physiology and Endocrinology 2
Format: Poster
Day/Time: Wednesday 7:30 AM–9:30 AM
Location: Exhibit Hall A
Session: Physiology and Endocrinology 2
Format: Poster
Day/Time: Wednesday 7:30 AM–9:30 AM
Location: Exhibit Hall A
# W81
Increasing supply of methionine and arginine at constant Thr:Phe, Lys:Thr, Lys:His, and Lys:Val ratios alters inflammatory and oxidative stress responses during a lipopolysaccharide challenge in bovine mammary epithelial cells.
H. Dai*1,2, D. N. Coleman1, L. Hu1,3, I. Martinez-Cortés1,4, X. Shen2, J. J. Loor1, 1University of Illinois, Urbana, IL, 2Nanjing Agricultural University, Nanjing, Jiangsu, China, 3Yangzhou University, Yangzhou, Jiangsu, China, 4National Autonomous University of Mexico, Mexico City, Mexico.
Key Words: amino acid, lactation, mastitis
Increasing supply of methionine and arginine at constant Thr:Phe, Lys:Thr, Lys:His, and Lys:Val ratios alters inflammatory and oxidative stress responses during a lipopolysaccharide challenge in bovine mammary epithelial cells.
H. Dai*1,2, D. N. Coleman1, L. Hu1,3, I. Martinez-Cortés1,4, X. Shen2, J. J. Loor1, 1University of Illinois, Urbana, IL, 2Nanjing Agricultural University, Nanjing, Jiangsu, China, 3Yangzhou University, Yangzhou, Jiangsu, China, 4National Autonomous University of Mexico, Mexico City, Mexico.
We evaluated whether increased supply of Met and Arg alone or in combination altered inflammation and oxidative stress responses in primary bovine mammary cells (BMEC) challenged with lipopolysaccharide (LPS). The BMEC (n = 4 replicates/treatment) were incubated for 12 h with control medium (IPAA, Lys:Met 2.9:1, Lys:Arg 2:1) or medium supplemented with Met (LM2.5; Lys:Met 2.5:1, Lys:Arg 2:1), Arg (LA; Lys:Met 2.9:1, Lys:Arg 1:1), or LM2.5+LA (Lys:Met 2.5:1, Lys:Arg 1:1). Ratios of Thr:Phe (1.05:1), Lys:Thr (1.8:1), Lys:His (2.38:1), and Lys:Val (1.23:1) were constant across treatments. Cells were then incubated with or without LPS (1,000 ng/mL) for another 6 h. Data were analyzed as a 2 × 2 × 2 factorial arrangement of treatments with the MIXED procedure of SAS 9.4. Target genes were measured by RT-PCR and proteins by Western blotting. LPS downregulated mRNA abundance of the amino acid transporters SLC7A5, SLC7A1 and SLC36A1. However, Arg supply alone attenuated the downregulation of SLC36A1 mRNA and SLC7A1 mRNA. LPS upregulated mRNA abundance of KEAP1 and protein abundance of CUL3, and both of them inhibit the antioxidant transcription factor NFE2L2 which was associated with lower protein abundance of NFE2L2 and the antioxidant proteins NQO1 and GPX1. Protein abundance of phosphorylated p65 (RELA; NFKB1 activator) was greater after LPS stimulation, but the response was attenuated by supply of Met alone. Similar responses to LPS and increased supply of Met plus Arg were observed for the ratio of p-RELA to total RELA. mRNA abundance of proinflammatory cytokines and chemokines (IL1B and CXCL2) was greater after LPS stimulation, but the response was attenuated with greater supply of Met and Arg alone. Although greater supply of Met and Arg could not rescue the inhibition of antioxidant mechanisms controlled by NFE2L2, overall, the data suggest that these amino acids dampened the proinflammatory responses triggered by LPS. One of the underlying mechanisms was through the control of NFKB1 activity and abundance of proinflammatory cytokines and chemokines.
Key Words: amino acid, lactation, mastitis
