Submitted to: Joint Abstracts of the American Dairy Science and Society of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: 3/30/2015
Publication Date: N/A
Technical Abstract: Alpha 1-acid glycoprotein (AGP) is the most abundant protein in serum of neonatal swine. This protein functions as an immunomodulator in the pig. Recent work has demonstrated that adipose tissue can express AGP mRNA, as well as numerous cytokine mRNA. The present study was designed to determine if AGP can alter expression of pro-inflammatory and/or anti-inflammatory cytokines expression in neonatal porcine subcutaneous adipose tissue (SAT) in vitro. Comparison of the postnatal development of AGP expression in liver with SAT from pre-weaning piglets demonstrated that liver AGP was highly expressed at d1 and decreased five-fold by d7 (P < 0.001), with no further change at d21, while SAT AGP gene expression was much lower than in liver (P < 0.001) and did not vary with pre-weaning age (P > 0.05). Isolation of adipocytes from stromal-vascular cells (SV) at d21 by collagenase digestion and flotation techniques demonstrated that adipocytes specifically express the AGP mRNA, but there is no difference in AGP mRNA abundance between these two cell populations (P > 0.05). Primary cell cultures derived from neonatal SAT were used to examine AGP effects on cytokine gene expression. SV cells were isolated from SAT of 3 to 7 day old piglets and allowed to proliferate to confluency, then differentiated in vitro and permitted to fill with lipid. Subsequently, the adipocyte containing cultures were assessed for response to 24 hours of incubation with 0, 100, 1000 or 5000 ng porcine AGP/mL medium. Interleukin 6 gene expression was reduced by 32% (P < 0.01) as measured by real time PCR. The inhibition of macrophage migration inhibitory factor mRNA abundance by AGP was dose responsive (P < 0.01). AGP treatment also reduced the acute phase protein, plasminogen activator inhibitor 1 by 46% (P < 0.001). Interleukin 10, adiponectin and tumor necrosis a were unaffected by AGP treatment (P > 0.05). These data indicate that porcine AGP has selective anti-inflammatory effects on cytokine expression by neonatal porcine adipose tissue in vitro.