Mitochondrial uncoupling protein 2 (UCP2) in the nonhuman primate brain and pituitary.
Energy dissipating mechanisms and their regulatory components represent key elements of metabolism and may offer novel targets in the treatment of metabolic disorders, such as obesity and diabetes. Recent studies have shown that a mitochondrial uncoupling protein (UCP2), which uncouples mitochondrial oxidation from phosphorylation, is expressed in the rodent brain by neurons that are known to regulate autonomic, metabolic, and endocrine processes. To help establish the relevance of these rodent data to primate physiology, we now examined UCP2 messenger RNA and peptide expressions in the brain and pituitary gland of nonhuman primates. In situ hybridization histochemistry showed that UCP2 messenger RNA is expressed in the paraventricular, supraoptic, suprachiasmatic, and arcuate nuclei of the primate hypothalamus and also in the anterior lobe of the pituitary gland. Immunocytochemistry revealed abundant UCP2 expression in cell bodies and axonal processes in the aforementioned nuclei as well as in other hypothalamic and brain stem regions and all parts of the pituitary gland. In the hypothalamus, UCP2 was coexpressed with neuropeptide Y, CRH, oxytocin, and vasopressin. In the pituitary, vasopressin and oxytocin-producing axonal processes in the posterior lobe and POMC cells in the intermediate and anterior lobes expressed UCP2. On the other hand, none of the GH-producing cells of the anterior pituitary was found to produce UCP2. The abundance and distribution pattern of UCP2 in the primate brain and pituitary suggest that this protein is evolutionary conserved and may relate to central autonomic, endocrine and metabolic regulation.
Diano
S
S
Department of Obstetrics and Gynecology, Yale University School of Medicine, New Haven, Connecticut 06520, USA. sabrina.diano@yale.edu
Urbanski
H F
HF
Horvath
B
B
Bechmann
I
I
Kagiya
A
A
Nemeth
G
G
Naftolin
F
F
Warden
C H
CH
Horvath
T L
TL
D000818:Animals; D001923:Brain Chemistry; D002522:Chlorocebus aethiops; D003346:Corticotropin-Releasing Hormone / Q000032:analysis; D015870:Gene Expression; D007031:Hypothalamus / Q000737:chemistry; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007473:Ion Channels; D008032:Limbic System / Q000737:chemistry; D008252:Macaca fascicularis; D008253:Macaca mulatta; D026901:Membrane Transport Proteins; D008856:Microscopy, Fluorescence; D024101:Mitochondrial Proteins; D009478:Neuropeptide Y / Q000032:analysis; D010121:Oxytocin / Q000032:analysis; D010902:Pituitary Gland / Q000737:chemistry*; D010903:Pituitary Gland, Anterior / Q000737:chemistry; D010904:Pituitary Gland, Posterior / Q000737:chemistry; D011506:Proteins / Q000032:analysis* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D000071246:Uncoupling Protein 2; D014667:Vasopressins / Q000032:analysis
D007473:Ion Channels; D026901:Membrane Transport Proteins; D024101:Mitochondrial Proteins; D009478:Neuropeptide Y; D011506:Proteins; D012333:RNA, Messenger; D000071246:Uncoupling Protein 2; D014667:Vasopressins; D010121:Oxytocin; D003346:Corticotropin-Releasing Hormone