Submitted to: Journal of Animal Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/28/2007
Publication Date: 7/20/2007
Citation: Hausman, G.J., Barb, C.R., Dean, R.G. 2007. Patterns of gene expression in pig adipose tissue: transforming growth factors, interferons, interleukins and apolipoproteins. Journal of Animal Science. p. 2445-2456. Interpretive Summary: Rodent and human studies show that fat tissue secretes many cytokines indicating that fat tissue plays an unexpected but important role in physiological and inflammatory responses. Identification of cytokines secreted by fat tissue continues on as global approaches are used to study fat tissue proteins and genes. A number of pig fat tissue cytokine genes were studied in growing pigs. Most cytokine gene levels examined did not change with age. However, several cytokine gene levels changed
Technical Abstract: Total RNA was collected at slaughter from outer s.c. adipose tissue (OSQ), middle s.c. adipose tissue (MSQ), ovary, uterus, hypothalamus, and pituitary tissues samples from gilts at 90, 150, and 210 d ( n =5 / age). Dye labeled cDNA probes were hybridized to custom microarrays (70 mer oligonucleotides) representing about 600 pig genes involved in growth and reproduction. In an earlier study, total RNA was isolated from adipose tissue from 105 d fetuses (n =2) and neonatal (5 d old) pigs (n=2) and subjected to microarray analysis as above. Cy3 / Cy5 intensity ratios revealed little change in expression of twenty seven cytokines with age in adipose tissue from growing pigs (90,150 and 210 d). The relative expression or patterns of expression within interleukins, interferons and transforming growth factor ' family members distinguished growing pig adipose tissue from neonatal (fetal + 5 d old pig) adipose tissue. We demonstrated, for the first time, the expression of seven major cytokine genes in pig adipose tissue including RANTES, interleukin (IL)-1B, IL-1A, IL-12A and IL-1 receptor antagonist with microarray and RT-PCR assays or RT-PCR assays alone. Pearsons correlation coefficients and simple linear regression analysis revealed strong and significant relationships between real time RT-PCR assay crossing points and matching microarray intensities. These studies demonstrate the expression of major cytokine genes in pig adipose tissue that may influence local and central metabolism and growth.