Thyroid status, but not insulin status, affects expression of avian uncoupling protein mRNA in chicken.
The aim of this study was to investigate the hormonal regulation of the avian homolog of mammalian uncoupling protein (avUCP) by studying the impact of thyroid hormones and insulin on avUCP mRNA expression in chickens (Gallus gallus). For 3 wk, chicks received either a standard diet (control group), or a standard diet supplemented with triiodothyronine (T(3); T3 group) or with the thyroid gland inhibitor methimazole (MMI group). A fourth group received injections of the deiodinase inhibitor iopanoic acid (IOP group). During the 4th wk of age, all animals received two daily injections of either human insulin or saline solution. The results indicate a twofold overexpression of avUCP mRNA in gastrocnemius muscle of T3 birds and a clear downregulation (-74%) in MMI chickens compared with control chickens. Insulin injections had no significant effect on avUCP mRNA expression in chickens. This study describes for the first time induction of avUCP mRNA expression by the thermogenic hormone T(3) in chickens and supports a possible involvement of avUCP in avian thermogenesis.
Collin
Anne
A
Station de Recherches Avicoles, Institut National de la Recherche Agronomique, F-37380 Nouzilly, France. collin@tours.inra.fr
Taouis
Mohammed
M
Buyse
Johan
J
Ifuta
Ndey B
NB
Darras
Veerle M
VM
Van As
Pieter
P
Malheiros
Ramon D
RD
Moraes
Vera M B
VM
Decuypere
Eddy
E
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001833:Body Temperature Regulation / Q000502:physiology; D001835:Body Weight / Q000187:drug effects; D002352:Carrier Proteins / Q000235:genetics*; D002645:Chickens / Q000254:growth & development / Q000378:metabolism*; D004435:Eating / Q000187:drug effects; D005230:Fatty Acids, Nonesterified / Q000097:blood; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007328:Insulin / Q000494:pharmacology*; D007473:Ion Channels; D008099:Liver / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D024101:Mitochondrial Proteins; D012333:RNA, Messenger / Q000032:analysis; D013961:Thyroid Gland / Q000254:growth & development / Q000502:physiology*; D013963:Thyroid Hormones / Q000097:blood; D014280:Triglycerides / Q000097:blood; D000071256:Uncoupling Protein 1
D001786:Blood Glucose; D002352:Carrier Proteins; D005230:Fatty Acids, Nonesterified; D007004:Hypoglycemic Agents; D007328:Insulin; D007473:Ion Channels; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D012333:RNA, Messenger; D013963:Thyroid Hormones; D014280:Triglycerides; D000071256:Uncoupling Protein 1