Differential effects of leptin on thermoregulation and uncoupling protein abundance in the neonatal lamb.
As the role of leptin in energy balance in neonate is unknown, we investigated the effect of acute (2 h) and chronic (7 days) administration of leptin (100 microg/day) on thermoregulation and mitochondrial protein abundance in adipose tissue. The concentration of uncoupling protein (UCP)1 and voltage-dependent anion channel (VDAC) located on the inner and outer mitochondrial membranes, respectively, were measured. Administration of leptin prevented the normal decline in colonic temperature over the first few hours and days after birth. It subsequently accelerated the loss of both mRNA and protein for UCP1 but had no effect on VDAC abundance. At seven days of age, colonic temperature was correlated strongly with both mRNA abundance and thermogenic potential of UCP1 in leptin-treated but not control lambs, indicating more effective use of UCP1 for heat production following leptin administration. Leptin had no effect on weight gain or adipose tissue deposition; at one day of age only, leptin mRNA was correlated positively with adipose tissue weight. In conclusion, leptin administration to neonatal lambs improves thermoregulation and promotes the loss of UCP1 in brown adipose tissue.
Academic Division of Child Health, School of Human Development, University Hospital, Queen's Medical Centre, Nottingham, NG7 2UH.
Alison
A
Mostyn
Jayson
J
Bispham
Sarah
S
Pearce
Yvonne
Y
Evens
Nina
N
Raver
Duane H
DH
Keisler
Robert
R
Webb
Terence
T
Stephenson
Michael E
ME
Symonds
D002001:Adipose Tissue, Brown / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D000818:Animals; D000831:Animals, Newborn; D001833:Body Temperature Regulation / Q000187:drug effects; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D003106:Colon / Q000502:physiology; D007473:Ion Channels; D020738:Leptin / Q000494:pharmacology*; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D024101:Mitochondrial Proteins; D008954:Models, Biological; D012333:RNA, Messenger / Q000096:biosynthesis; D012756:Sheep; D000071256:Uncoupling Protein 1
D002352:Carrier Proteins; D007473:Ion Channels; D020738:Leptin; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D012333:RNA, Messenger; C000604371:UCP1 protein, human; D000071256:Uncoupling Protein 1