Arginine Relieves the Inflammatory Response and Enhances the Casein Expression in Bovine Mammary Epithelial Cells Induced by Lipopolysaccharide

Abstract

As one of functional active amino acids, L-arginine holds a key position in immunity. However, the mechanism that arginine modulates cow mammary inflammatory response in ruminant is unclear. Therefore, this study was conducted to investigate the effects of L-arginine on inflammatory response and casein expression after challenging the bovine mammary epithelial cells (BMECs) with lipopolysaccharide (LPS). The cells were divided into four groups, stimulated with or without LPS (10 μg/mL) and treated with or without arginine (100 μg/mL) for 12 h. The concentration of proinflammatory cytokines, inducible nitric oxide synthase (iNOS), mammalian target of rapamycin (mTOR), and Toll-like receptor 4 (TLR4) signaling pathways as well as the casein was determined. The results showed that arginine reduced the LPS-induced production like IL-1β, IL-6, TNF-α, and iNOS. Though the expression of NF-κB was attenuated and the mTOR signaling pathway was upregulated, arginine had no effect on TLR4 expression. In addition, our results show that the content of β-casein and the total casein were enhanced after arginine was supplemented in LPS-induced BMECs. In conclusion, arginine could relieve the inflammatory reaction induced by LPS and enhance the concentration of β-casein and the total casein in bovine mammary epithelial cells.

Mastitis Süresince Meme Epitel Hücrelerinin Fonksiyonel Durumunu Değerlendirmek Amacıyla Sığır α-kazein Proteinine Karşı Monoklonal Antikor Geliştirilmesi

“…3D). Our results are consistent with previous studies and showed that the expression of caseins were not significantly changed or even decreased when an animal is in mastitis [15,16] .…”

“…However, the changes of different caseins are different. Using an ELISA method, it was found that β-casein decreased significantly during mastitis, while the content of α-casein did not change significantly [15] , which was in compliance with the results of several other studies [25,27] . In this study, we found that the content of α-casein of primary MECs did not change significantly under the stimulation of various concentrations of LPS, indicating that MA, WANG, GAO, NING LIU, LI, GAO, LU, CHEN the expression level of α-casein does not alter significantly during mastitis.…”

“…Plenty of evidence exists that confirms the ability of MECs to synthesize and secrete casein changes under different conditions [15,26] , and it is very important to measure these changes for the evaluation of cellular function. The total casein content showed a decreasing trend in an in vitro mastitis model.…”

PGN and LTA from Staphylococcus aureus Induced Inflammation and Decreased Lactation through Regulating DNA Methylation and Histone H3 Acetylation in Bovine Mammary Epithelial Cells

“…Meanwhile, the protein expression of CSN2 and CSN3 also was reduced, which was consistent with their gene expression. This indicated that casein expression decreased when inflammation occurred in the bovine mammary epithelial cells after being stimulated by the pathogenic factors [52][53][54].…”

Inhibition of arginase via jugular infusion of Nω-hydroxy-nor-l-arginine inhibits casein synthesis in lactating dairy cows

“…Recently, some studies revealed that Arg, a conditionally essential AA, also has some positive effects on the synthesis of milk protein (Mabjeesh et al, 2002;Doepel and Lapierre, 2011). Some recent studies (Chen et al, 2013;Wu et al, 2016) have demonstrated that the addition of Arg in culture medium increased casein protein synthesis in bovine mammary epithelial cells (BMEC). Moreover, Wang et al infused Arg through jugular vein in dairy cows to measure the effects of Arg infusion on milk protein synthesis in vivo.…”