title: Acute phase response in lactating dairy cows during hyperinsulinemic hypoglycaemic and hyperinsulinemic euglycaemic clamps and after intramammary LPS challenge.
abstract: The link between energy availability, turnover of energy substrates and the onset of inflammation in dairy cows is complex and poorly investigated. To clarify this, plasma inflammatory variables were measured in mid-lactating dairy cows allocated to three groups: hyperinsulinemic hypoglycaemic clamp, induced by insulin infusion (HypoG, n = 5); hyperinsulinemic euglycaemic clamp, induced by insulin and glucose infusion (EuG; n = 6); control, receiving a saline solution infusion (NaCl; n = 6). At 48 h after the start of i.v. infusions, two udder quarters per cow were challenged with 200 μg of E. coli lipopolysaccharide (LPS). Individual blood samples were taken before clamps, before LPS challenge (i.e. 48 h after clamps) and 6.5 h after. At 48 h, positive acute phase proteins (posAPP) did not differ among groups, whereas albumin and cholesterol (index of lipoproteins), negative APP (negAPP), were lower (p < 0.05) in EuG compared to NaCl and HypoG. The concentration of IL-6 was greater in EuG (p < 0.05) but only vs. HypoG. At 6.5 h following LPS challenge, IL-6 increased in the NaCl and EuG clamps (p < 0.05), while TNF-α increased (p < 0.05) in the EuG only. Among the posAPP, haptoglobin markedly increased in EuG (p < 0.05), but not in NaCl (p = 0.76) and in HypoG; ceruloplasmin tended to decline during LPS challenge, the reduction was significant when all animals were considered (p < 0.05). Conversely, all the negAPP showed a marked reduction 6.5 h after LPS challenge in the three groups. In conclusion, EuG caused an inflammatory status after 48-h infusion (i.e. decrease of negAPP) and induced a quicker acute phase response (e.g. marked rise of TNF-α, IL-6) after the intramammary LPS challenge. These data suggest that the simultaneous high availability of glucose and insulin at the tissue-level makes dairy cows more susceptible to inflammatory events. In contrast, HypoG seems to attenuate the inflammatory response.
authors.affiliation: Istituto di Zootecnica, Facoltà di Scienze Agrarie, Alimentari ed Ambientali, Università Cattolica del Sacro Cuore, Piacenza, Italy.
authors.forename: L
authors.initials: L
authors.lastname: De Matteis
authors.affiliation: Istituto di Zootecnica, Facoltà di Scienze Agrarie, Alimentari ed Ambientali, Università Cattolica del Sacro Cuore, Piacenza, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Bertoni
authors.affiliation: Istituto di Zootecnica, Facoltà di Scienze Agrarie, Alimentari ed Ambientali, Università Cattolica del Sacro Cuore, Piacenza, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Lombardelli
authors.affiliation: Veterinary Physiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
authors.forename: O
authors.initials: O
authors.lastname: Wellnitz
authors.affiliation: Veterinary Physiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
authors.forename: H A
authors.initials: HA
authors.lastname: Van Dorland
authors.affiliation: Veterinary Physiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
authors.forename: M C M B
authors.initials: MCMB
authors.lastname: Vernay
authors.affiliation: Veterinary Physiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
authors.forename: R M
authors.initials: RM
authors.lastname: Bruckmaier
authors.affiliation: Istituto di Zootecnica, Facoltà di Scienze Agrarie, Alimentari ed Ambientali, Università Cattolica del Sacro Cuore, Piacenza, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Trevisi
mesh_terms: D000210:Acute-Phase Reaction; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism*; D002417:Cattle; D005260:Female; D005947:Glucose / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D015309:Glucose Clamp Technique / Q000662:veterinary*; D007328:Insulin / Q000097:blood / Q000494:pharmacology*; D007774:Lactation; D008070:Lipopolysaccharides / Q000633:toxicity*; D008321:Mammary Glands, Animal / Q000187:drug effects*
chemical_list: D001786:Blood Glucose; D007328:Insulin; D008070:Lipopolysaccharides; D005947:Glucose
keywords: glucose infusion; inflammation; insulin infusion; interleukin-6; mammary endotoxin challenge; tumour necrosis factor-alpha