Gene expression in adipose tissue of dairy cattle changes in early lactation or with supplemental chromium, integrating expression into metabolic models

摘要

The role of adipose tissue in reproduction has been a matter of study for decades. The pinnacle of adipose tissue function is reached in pregnancy and lactation, in which hormonal and neural signals combine to first increase adipose stores and then use them during later pregnancy or lactation, followed by restoration for the next reproductive cycle. In fact, several hormones that function in control of mammalian pregnancy and lactation, such as estrogen, progesterone, prolactin, somatotropin and placental lactogen, have important direct effects on adipose tissue metabolism and gene expression. In our laboratory we have studied intensively the role of adipose tissue in the energetics of pregnancy and lactation in cattle, pigs and laboratory animals.Adipose tissue, in addition to being a major energy storage organ, is also a source of regulatory and health proteins including IGFI, leptin, and immune function proteins. We conducted an analysis of gene expression in adipose tissue of dairy cattle in late pregnancy and early lactation. One objective was to determine changes in gene expression between 30 dprepartum and 30 d postpartum; another objective was to determine if supplemental Chromium Propionate (as KemTRACE brand Chromium Propionate Cr; CrP) altered intake, production, adipose metabolism or gene expression. The long-term objective is to begin to integrate gene expression maps into models of energy and nutrient metabolism.