Increased plasma leptin attenuates adaptive metabolism in early lactating dairy cows

Richard A. Ehrhardt, Andreas Foskolos, Sarah L. Giesy, Stephanie R. Wesolowski, Christopher S. Krumm, W. Ronald Butler, Susan M. Quirk, Matthew R. Waldron, Yves R. Boisclair

Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

Crynodeb

Mammals meet the increased nutritional demands of lactation through a combination of increased feed intake and a collection of adaptations known as adaptive metabolism (e.g., glucose sparing via insulin resistance, mobilization of endogenous reserves, and increased metabolic efficiency via reduced thyroid hormones). In the modern dairy cow, adaptive metabolism predominates over increased feed intake at the onset of lactation and develops concurrently with a reduction in plasma leptin. To address the role of leptin in the adaptive metabolism of early lactation, we asked which adaptations could be countered by a constant 96-h intravenous infusion of human leptin (hLeptin) starting on day 8 of lactation. Compared to saline infusion (Control), hLeptin did not alter energy intake or milk energy output but caused a modest increase in body weight loss. hLeptin reduced plasma glucose by 9% and hepatic glycogen content by 73%, and these effects were associated with a 17% increase in glucose disposal during an insulin tolerance test. hLeptin attenuated the accumulation of triglyceride in the liver by 28% in the absence of effects on plasma levels of the anti-lipolytic hormone insulin or plasma levels of free fatty acids, a marker of lipid mobilization from adipose tissue. Finally, hLeptin increased the plasma concentrations of T4 and T3 by nearly 50% without affecting other neurally regulated hormones (i.e., cortisol and luteinizing hormone (LH)). Overall these data implicate the periparturient reduction in plasma leptin as one of the signals promoting conservation of glucose and energy at the onset of lactation in the energy-deficient dairy cow.

Iaith wreiddiolSaesneg
Tudalennau (o-i)145-157
Nifer y tudalennau13
CyfnodolynJournal of Endocrinology
Cyfrol229
Rhif cyhoeddi2
Dynodwyr Gwrthrych Digidol (DOIs)
StatwsCyhoeddwyd - 01 Mai 2016

Ôl bys

Gweld gwybodaeth am bynciau ymchwil 'Increased plasma leptin attenuates adaptive metabolism in early lactating dairy cows'. Gyda’i gilydd, maen nhw’n ffurfio ôl bys unigryw.

Dyfynnu hyn