J Korean Neurosurg Soc.  2007 Dec;42(6):470-474. 10.3340/jkns.2007.42.6.470.

Identification of Novel Metabolic Proteins Released by Insulin Signaling of the Rat Hypothalmus Using Liquid Chromatography-Mass Spectrometry (LC-MS)

• Chin C

• KMID: 2189339
• DOI: http://doi.org/10.3340/jkns.2007.42.6.470

Abstract

OBJECTIVE
The brain is dependent on glucose as an energy source. Intricate homeostatic mechanisms have been implicated in maintaining the blood glucose concentration in the brain. The aim of this study is to find the way to identify the metabolic proteins regulating the glucose in rat hypothalamus.
METHODS
In this study, we analysed the secretome from rat hypothalamus in vivo. We introduced 500 nM of insulin into the rat hypothalamus. The chromatographic patterns of the secretome were identified, after which Mass Spectrometry-Mass Spectrometry (MS-MS) analysis was performed.
RESULTS
In Liquid Chromatography-Mass Spectrometry (LC-MS) analysis, 60 proteins were identified in the secretome. Among them, 8 novel proteins were unveiled and were associated with the energy metabolism of insulin signaling in mitochondria of rat hypothalamic neuron. Nineteen other proteins have unknown functions. These ligands were confirmed to be secreting from the rat hypothalmus on insulin signaling by western blotting.
CONCLUSION
The hypothalamus is the master endocrine gland responsible for the regulation of various physiological and metabolic processes. Proteomics using LC-MS analysis offer a efficient means for generating a comprehensive analysis of hypothalamic protein expression by insulin signaling.

Keyword

Insulin; Energy metabolism; Hypothalamus; Liquid chromatography; Mass spectrometry

MeSH Terms

Animals
Blood Glucose
Blotting, Western
Brain
Chromatography, Liquid
Endocrine Glands
Energy Metabolism
Glucose
Hypothalamus
Insulin*
Ligands
Mass Spectrometry
Metabolism
Mitochondria
Neurons
Proteomics
Rats*
Spectrum Analysis*
Tandem Mass Spectrometry
Blood Glucose
Glucose
Insulin
Ligands