Defining the Adipose Tissue Proteome of Dairy Cows to Reveal Biomarkers Related to Peripartum Insulin Resistance and Metabolic Status

Abstract

Adipose tissue is a central regulator of metabolism in dairy cows; however, little is known about the association between various proteins in adipose tissue and the metabolic status of peripartum cows. Therefore, the objectives were to (1) examine total protein expression in adipose tissue of dairy cows and (2) identify biomarkers in adipose that are linked to insulin resistance and to cows' metabolic status. Adipose tissue biopsies were obtained from eight multiparous cows at -17 and +4 days relative to parturition. Proteins were analyzed by intensity-based, label-free, quantitative shotgun proteomics (nanoLC-MS/MS). Cows were divided into groups with insulin-resistant (IR) and insulin-sensitive (IS) adipose according to protein kinase B phosphorylation following insulin stimulation. Cows with IR adipose lost more body weight postpartum compared with IS cows. Differential expression of 143 out of 586 proteins was detected in prepartum versus postpartum adipose. Comparing IR to IS adipose revealed differential expression of 18.9% of the proteins; those related to lipolysis (hormone-sensitive lipase, perilipin, monoglycerol lipase) were increased in IR adipose. In conclusion, we found novel biomarkers related to IR in adipose and to metabolic status that could be used to characterize high-yielding dairy cows that are better adapted to peripartum metabolic stress.

Adipose tissue lipolysis and remodeling during the transition period of dairy cows

“…During active AT remodeling, the expression and secretion of IL1-β, IL-6, resistin, and TNF-α by human adipocytes and ATM is increased, leading to impaired AT insulin signaling [74, 88]. In transition dairy cows, AT expression of IL-6, resistin, TNF-α, and other bioactive peptides associated with IR is increased compared to other stages of lactation [120–122]. Recent studies provide evidence for AT-specific IR during early lactation in high-yielding dairy cows.…”

Proteome dataset of subcutaneous adipose tissue obtained from late pregnant dairy cows during summer heat stress and winter seasons

“…Our previous work showed that the degree of BW loss postpartum affects the proteome of adipose tissue in late-pregnant cows [5], and we therefore defined each cow as either high weight loss (HWL) or low weight loss (LWL) according to the percentage of BW loss from week 1 to week 5 postpartum as previously described [5], [9]. These subgroups were added to the statistical model.…”

“…Environmental heat stress is one of the main stressors limiting production in dairy cattle (Fuquay, 1981; West, 2003) [2], [3], and there is a complex interaction between heat stress and the transition period from late pregnancy to onset of lactation, which is manifested in heat-stressed late-gestation cows (Tao and Dahl, 2013) [4]. We recently defined the proteome of adipose tissue in peripartum dairy cows, identifying 586 proteins of which 18.9% were differentially abundant in insulin-resistant compared to insulin-sensitive adipose tissue (Zachut, 2015) [5]. That study showed that proteomic techniques constitute a valuable tool for identifying novel biomarkers in adipose tissue that are related to metabolic adaptation to stress in dairy cows.…”

Unraveling the Adipose Tissue Proteome of Transition Cows through Severe Negative Energy Balance

“…Insulin resistance could represent another important feature to take into account. The differential protein expression of adipose tissue in cows has been evaluated in relation to insulin resistance [10]. We evaluated the differential protein expression of adipose tissue from cows grouped according to insulin resistance or sensitivity following the evaluation of protein kinase B phosphorylation after insulin stimulation.…”

“…However, in dairy cows, little is known about the relation between adipose tissue proteins and the metabolic status in peripartum. Previous studies of adipose tissue of cows among parturition showed a differential abundance of proteins related to the insulin resistance phenomenon [10] and provided novel biomarkers for this condition. Using proteomic studies, Zachut et al also identified novel biomarkers of heat stress in adipose tissue in late-pregnant cows [11].…”