Early-life exposure to testosterone programs the hypothalamic melanocortin system

Endocrinology. 2011 Apr;152(4):1661-9. doi: 10.1210/en.2010-1288. Epub 2011 Feb 8.

Abstract

In mammals, males consume more food, which is considered a masculinized behavior, but the underlying mechanism of this sex-specific feeding behavior is unknown. In mice, neonatal testosterone (NT) is critical to masculinize the developing brain, leading to sex differences in reproductive physiology. The proopiomelanocortin (POMC) neurons of the hypothalamic arcuate nucleus (ARC) are critical to suppress energy intake and POMC innervation of hypothalamic feeding circuits develops to a large extent neonatally. We hypothesized that NT programs the masculinization of energy intake by programming POMC neurons. We tested this hypothesis by comparing control females and control males (CMs) with female mice neonatally androgenized with testosterone (NTFs). We show that increased food intake in CMs is associated with reduced POMC expression and decreased intensity of neuronal projections from POMC neurons within the ARC compared with control females. We found that NTFs display a masculinized energy intake and ARC POMC expression and innervation as observed in CMs, which can be mimicked by neonatal exposure to the androgen receptor agonist dihydrotestosterone (DHT). NTFs also exhibit hyperleptinemia and a decreased ability of leptin to up-regulate POMC, suppress food intake, and prevent adipose tissue accumulation, independent of signal transducer and activator of transcription 3. However, this leptin resistance is specific to NTFs, is not a consequence of masculinization, and is reproduced by neonatal exposure to estrogen but not DHT. Thus, NT programs a sexual differentiation of POMC neurons in female mice via DHT but also predisposes to leptin resistance and obesity in an estrogen-dependent manner.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arcuate Nucleus of Hypothalamus / cytology*
  • Arcuate Nucleus of Hypothalamus / drug effects
  • Blotting, Western
  • Eating / drug effects
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Hypothalamus / drug effects
  • Hypothalamus / metabolism*
  • Immunohistochemistry
  • Leptin / pharmacology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Neurons / drug effects
  • Neurons / metabolism*
  • Pro-Opiomelanocortin / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Testosterone / pharmacology*

Substances

  • Leptin
  • Testosterone
  • Pro-Opiomelanocortin