Periparturient lipolysis and oxylipid biosynthesis in bovine adipose tissues

Abstract

The periparturient period of dairy cows is characterized by intense lipolysis in adipose tissues (AT), which induces the release of free fatty acids (FFA) into circulation. Among FFA, polyunsaturated fatty acids are susceptible to oxidation and can modulate inflammatory responses during lipolysis within AT. Linoleic and arachidonic acid oxidized products (oxylipids) such as hydroxy-octadecadienoic acids (HODE) and hydroxy-eicosatetraenoic acids (HETE), were recently identified as products of lipolysis that could modulate AT inflammation during lipolysis. However, the effect of lipolysis intensity during the transition from gestation to lactation on fatty acid substrate availability and subsequent AT oxylipid biosynthesis is currently unknown. We hypothesized that in periparturient dairy cows, alterations in AT and plasma fatty acids and oxylipid profiles coincide with changes in lipolysis intensity and stage of lactation. Blood and subcutaneous AT samples were collected from periparturient cows at -27±7 (G1) and -10±5 (G2) d prepartum and at 8±3 d postpartum (PP). Targeted lipidomic analysis was performed on plasma and AT using HPLC-MS/MS. We report that FFA concentrations increased as parturition approached and were highest at PP. Cows exhibiting high lipolysis rate at PP (FFA>1.0 mEq/L) had higher body condition scores at G1 compared to cows with low lipolysis rate (FFA<1.0 mEq/L). Concentrations of plasma linoleic and arachidonic acids were increased at PP. In AT, 13-HODE, and 5-, 11- and 15-HETE were increased at PP compared to G1 and G2. Concentrations of beta hydroxybutyrate were positively correlated with those of 13-HODE and 15-HETE in AT. Plasma concentrations of 5- and 20-HETE were increased at PP. These data demonstrate that prepartum adiposity predisposes cows to intense lipolysis post-partum and may exacerbate AT inflammation because of increased production of pro-inflammatory oxylipids including 5- and 15-HETE and 13-HODE. These results support a role for certain linoleic and arachidonic acid-derived oxylipids as positive and negative modulators of AT inflammation during periparturient lipolysis.

Production of 15-F-isoprostane as an assessment of oxidative stress in dairy cows at different stages of lactation

“…Thus, the methods used to measure isoprostanes should 9293 be carefully considered when comparing studies in the scientific literature and interpreting the information. Additional differences, such as those noted between Contreras et al (2017) and the presented results, may stem from differences in the basal redox status of cattle that live under different management conditions and are fed different rations (Hanschke et al, 2016;Khatti et al, 2017). Sampling time may also contribute to published differences because small changes in the physiological state of a cow may significantly affect isoprostane production.…”

Short communication: Effects of body fat mobilization on macrophage infiltration in adipose tissue of early lactation dairy cows

“…Blood and subcutaneous AT samples were taken at 27 ± 2.2 d (far-off) and 10 ± 1.5 d (close-up) before calving and 9 ± 0.3 d after parturition (fresh). The AT samples were collected from the tailhead using minimally invasive surgical techniques as previously described (Contreras et al, 2017a). Three to five grams of subcutaneous AT were obtained from the surgical site.…”

“…Blood samples were collected 2 h before adipose sample collections via coccygeal venipuncture using uncoated serum collection tubes, centrifuged for 20 min at 3,000 × g (15°C) for serum fraction collection, and stored at −80°C until further analysis. Serum concentrations of free fatty acids (FFA) and BHB were determined as described in Contreras et al (2017a).…”

Glutathione metabolism and nuclear factor erythroid 2-like 2 (NFE2L2)-related proteins in adipose tissue are altered by supply of ethyl-cellulose rumen-protected methionine in peripartal Holstein cows

“…When Lys was adequate, feeding RPM to achieve a Lys: Met ratio close to 2.8:1 in the MP during the periparturient period consistently alleviated oxidative stress status and inflammation in dairy cows and improved DMI and milk yield (Osorio et al, 2014b;Batistel et al, 2017;Zhou et al, 2017). Previous data have provided some indication that adipose may play a role in the induction of oxidative stress (Bernabucci et al, 2005;Contreras et al, 2017). For instance, in nonruminants, adipose tissue can secrete several adipokines that are associated with oxidative stress and inflammation (Shoelson et al, 2006;McGown et al, 2014;Murri et al, 2014).…”