Secreted proteins and genes in fetal and neonatal pig adipose tissue and stromal-vascular cells1

Abstract

Although microarray and proteomic studies have indicated the expression of unique and unexpected genes and their products in human and rodent adipose tissue, similar studies of meat animal adipose tissue have not been reported. Thus, total RNA was isolated from stromal-vascular (S-V) cell cultures (n = 4; 2 arrays; 2 cultures/array) from 90-d (79% of gestation) fetuses and adipose tissue from 105-d (92% of gestation) fetuses (n = 2) and neonatal (5-d-old) pigs (n = 2). Duplicate adipose tissue microarrays (n = 4) represented RNA samples from a pig and a fetus. Dye-labeled cDNA probes were hybridized to custom microarrays (70-mer oligonucleotides) representing more than 600 pig genes involved in growth and reproduction. Microarray studies showed significant expression of 40 genes encoding for known adipose tissue secreted proteins in fetal S-V cell cultures and adipose tissue. Expression of 10 genes encoding secreted proteins not known to be expressed by adipose tissue was also observed in neonatal adipose tissue and fetal S-V cell cultures. Additionally, the agouti gene was detected by reverse transcription-PCR in pig S-V cultures and adipose tissue. Proteomic analysis of adipose tissue and fetal and young pig S-V cell culture-conditioned media identified multiple secreted proteins including heparin-like epidermal growth factor-like growth factor and several apolipoproteins. Another adipose tissue secreted protein, plasminogen activator inhibitor-1, was identified by ELISA in S-V cell culture media. A group of 20 adipose tissue secreted proteins were detected or identified using the gene microarray and the proteomic and protein assay approaches including apolipoprotein-A1, apolipoprotein-E, relaxin, brain-derived neurotrophic factor, and IGF binding protein-5. These studies demonstrate, for the first time, the expression of several major secreted proteins in pig adipose tissue that may influence local and central metabolism and growth.

Adipose-Derived Stem Cells for Regenerative Medicine

“…Analyses of the ASC and adipocyte proteome by mass spectrometry and other approaches have documented the identity of Ͼ200 proteins in both the undifferentiated and adipose differentiated cells. [73][74][75][76][77][78][79] The human ASC proteome shares features in common to that reported for fibroblasts, MSCs, and other lineages. 74 …”

Adipose Tissue Derived Stem Cells Secretome: Soluble Factors and Their Roles in Regenerative Medicine

“…Nevertheless, the profile of the secretory products of ASCs has only recently begun to be characterized at the mass spectrometry level. Although there are a number of papers dedicated to ASCs proteomic characterization [43][44][45][46] , most of them are actually focused on the proteome of cell lysates rather than the characterization of the secretome itself. A recent study characterized the ASCs secretome in the context of differentiation towards the adipogenic lineage [47].…”

Slow Growing Pre-Weaning Piglets Have Altered Adipokine Gene Expression

“…Hausman et al [9] have previous reported that 5 -7 day old pig adipose tissue expresses a variety of adipokines. However, the present study is the first attempt to examine the relationship of growth rate and adipokine expression within adipose tissue in vivo during the preweaning period.…”

“…Leptin, adiponectin, lipoprotein lipase (LPL) and fatty acid synthase (FAS) were selected because they are markers for adipose differentiation in swine [16]. The interleukins 1β, 6 and 15 were included because they have been identified by Hausman et al [9] to be expressed by neonatal pig adipose tissue using proteomic analysis. Tumor necrosis factor α was examined as it has been the most characterized of all adipokines and has key regulatory roles in the expression of a variety of proteins, including the adipokines MIF and CCL2, which were included in this study.…”