Long-term infusion of brain-derived neurotrophic factor reduces food intake and body weight via a corticotrophin-releasing hormone pathway in the paraventricular nucleus of the hypothalamus.
Brain-derived neurotrophic factor (BDNF) has been implicated in learning, depression and energy metabolism. However, the neuronal mechanisms underlying the effects of BDNF on energy metabolism remain unclear. The present study aimed to elucidate the neuronal pathways by which BDNF controls feeding behaviour and energy balance. Using an osmotic mini-pump, BDNF or control artificial cerebrospinal fluid was infused i.c.v. at the lateral ventricle or into the paraventricular nucleus of the hypothalamus (PVN) for 12 days. Intracerebroventricular BDNF up-regulated mRNA expression of corticotrophin-releasing hormone (CRH) and urocortin in the PVN. TrkB, the receptor for BDNF, was expressed in the PVN neurones, including those containing CRH. Both i.c.v. and intra-PVN-administered BDNF decreased food intake and body weight. These effects of BDNF on food intake and body weight were counteracted by the co-administration of alpha-helical-CRH, an antagonist for the CRH and urocortin receptors CRH-R1/R2, and partly attenuated by a selective antagonist for CRH-R2 but not CRH-R1. Intracerebroventricular BDNF also decreased the subcutaneous and visceral fat mass, adipocyte size and serum triglyceride levels, which were all attenuated by alpha-helical-CRH. Furthermore, BDNF decreased the respiratory quotient and raised rectal temperature, which were counteracted by alpha-helical-CRH. These results indicate that the CRH-urocortin-CRH-R2 pathway in the PVN and connected areas mediates the long-term effects of BDNF to depress feeding and promote lipolysis.
Toriya
M
M
Division of Integrative Physiology, Department of Physiology, Jichi Medical University, Shimostuke, Tochigi, Japan.
Maekawa
F
F
Maejima
Y
Y
Onaka
T
T
Fujiwara
K
K
Nakagawa
T
T
Nakata
M
M
Yada
T
T
D000273:Adipose Tissue / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D001835:Body Weight / Q000187:drug effects* / Q000235:genetics; D019208:Brain-Derived Neurotrophic Factor / Q000008:administration & dosage* / Q000494:pharmacology; D003346:Corticotropin-Releasing Hormone / Q000008:administration & dosage / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology*; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D004353:Drug Evaluation, Preclinical; D004435:Eating / Q000187:drug effects* / Q000235:genetics; D057967:Infusions, Intraventricular; D008297:Male; D010286:Paraventricular Hypothalamic Nucleus / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D010446:Peptide Fragments / Q000008:administration & dosage / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D013997:Time Factors; D014280:Triglycerides / Q000097:blood
D019208:Brain-Derived Neurotrophic Factor; D010446:Peptide Fragments; D014280:Triglycerides; D003346:Corticotropin-Releasing Hormone; C045089:corticotropin releasing hormone (9-41)