Characterization of the endocannabinoid system in subcutaneous adipose tissue in periparturient dairy cows and its association to metabolic profiles

• Published in: PloS one 2018-11, Vol.13 (11), p.e0205996-e0205996
• Main Authors: Zachut, Maya, Kra, Gitit, Moallem, Uzi, Livshitz, Lilya, Levin, Yishai, Udi, Shiran, Nemirovski, Alina, Tam, Joseph
• Format: Article
• Language: English
• Subjects: 2-Arachidonoylglycerol; Adaptation; Adaptations; Adipocytes; Adipose tissue; Anandamide; Animal lactation; Animal sciences; Animal tissues; Arachidonic acid; Biology and Life Sciences; Body fat; Body weight; Body weight loss; Cannabinoid receptors; Cattle; Complement activation; Dairy cattle; Endocannabinoid system; Energy; Energy balance; Energy metabolism; Esterification; Fatty acids; Gene expression; Glucagon; Homeostasis; Inflammation; Information systems; Insulin; Insulin resistance; Laboratories; Lactation; Lipase; Lipids; Lipolysis; Medicine; Medicine and Health Sciences; Metabolic response; Metabolism; Obesity; Oleic acid; Oxidative stress; Palmitoylethanolamide; Pharmacy; Physical Sciences; Postpartum; Pregnancy; Receptors; Research and Analysis Methods; Weight control; Weight loss
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0205996

Adipose tissue (AT) plays a major role in metabolic adaptations in postpartum (PP) dairy cows. The endocannabinoid (eCB) system is a key regulator of metabolism and energy homeostasis; however, information about this system in ruminants is scarce. Therefore, this work aimed to assess the eCB system in subcutaneous AT, and to determine its relation to the metabolic profile in peripartum cows. Biopsies of AT were performed at 14 d prepartum, and 4 and 30 d PP from 18 multiparous peripartum cows. Cows were categorized retrospectively according to those with high body weight (BW) loss (HWL, 8.5 ± 1.7% BW loss) or low body weight loss (LWL, 2.9 ± 2.5% BW loss) during the first month PP. The HWL had higher plasma non-esterified fatty acids and a lower insulin/glucagon ratio PP than did LWL. Two-fold elevated AT levels of the main eCBs, N-arachidonoylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG), were found 4 d PP compared with prepartum in HWL, but not in LWL cows. AT levels of the eCB-like molecules oleoylethanolamide, palmitoylethanolamide, and of arachidonic acid were elevated PP compared with prepartum in all cows. The abundance of monoglyceride lipase (MGLL), the 2-AG degrading enzyme, was lower in HWL vs. LWL AT PP. The relative gene expression of the cannabinoid receptors CNR1 and CNR2 in AT tended to be higher in HWL vs. LWL PP. Proteomic analysis of AT showed an enrichment of the inflammatory pathways' acute phase signaling and complement system in HWL vs. LWL cows PP. In summary, eCB levels in AT were elevated at the onset of lactation as part of the metabolic adaptations in PP dairy cows. Furthermore, activating the eCB system in AT is most likely associated with a metabolic response of greater BW loss, lipolysis, and AT inflammation in PP dairy cows.