Leptin and its receptors

• This article summarized distribution of co-expression leptin receptor in the brain.
• We have focused the function and distribution the leptin receptor, especially ob–rb isoforms.
• We wrote the characterization of leptin and leptin receptor encode gene (ob and db gene).

Leptin is mainly produced in the white adipose tissue before being secreted into the blood and transported across the blood–brain barrier. Leptin binds to a specific receptor (LepR) that has numerous subtypes (LepRa, LepRb, LepRc, LepRd, LepRe, and LepRf). LepRb, in particular, is expressed in several brain nuclei, including the arcuate nucleus, the paraventricular nucleus, and the dorsomedial, lateral and ventromedial regions of the hypothalamus. LepRb is also co-expressed with several neuropeptides, including proopiomelanocortin, neuropeptide Y, galanin, galanin-like peptide, gonadotropin-releasing hormone, tyrosine hydroxylase and neuropeptide W. Functionally, LepRb induces activation of the JAK2/ERK, /STAT3, /STAT5 and IRS/PI3 kinase signaling cascades, which are important for the regulation of energy homeostasis and appetite in mammals. In this review, we discuss the structure, genetics and distribution of the leptin receptors, and their role in cell signaling mechanisms.