Role of leptin in reproduction.
OBJECTIVE
This article focuses on recently gained knowledge concerning the different emerging aspects of the role of leptin in reproduction, through both its central hypothalamus-mediated and peripheral actions.


RESULTS
As delineated in murine models, STAT3-independent signals triggered by the leptin receptor are clearly important in fertility, and candidate pathways such as those via phosphatidylinositol-3 kinase and extracellular signal-related kinase are implicated in leptin-regulated cascades. Another aspect whose importance has recently been revealed is that of the bioavailability of leptin in general, and the fate and action of carrier-bound versus free leptin at central and peripheral sites in particular.


CONCLUSIONS
Besides the well-established role of leptin in the control of appetite and energy expenditure in humans and animals, evidence for a major involvement of the hormone in the function of the reproductive system is rapidly accumulating through physiological and molecular genetic approaches. Powerful animal models that facilitate the dissection of increasingly complex pathways, together with detailed studies in man, will soon delineate in detail the diverse roles of leptin in biological regulation. The development of therapeutic agents primarily directed against obesity must therefore take into consideration the consequences of treatment not only on the amelioration of leptin resistance, but also on the bioactivity of leptin in the context of growth, glucose homeostasis, and last but not least, fertility.
Bajari
Tarek M
TM
Max F. Perutz Laboratories, Institute of Medical Biochemistry, Department of Molecular Genetics, Medical University of Vienna, Dr Bohr Gasse 9/2, A-1030 Vienna, Austria.
Nimpf
Johannes
J
Schneider
Wolfgang J
WJ
D000818:Animals; D004268:DNA-Binding Proteins / Q000502:physiology; D005298:Fertility / Q000502:physiology; D006066:Gonads / Q000502:physiology; D006801:Humans; D007031:Hypothalamus / Q000502:physiology; D007774:Lactation / Q000502:physiology; D020738:Leptin / Q000502:physiology*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010902:Pituitary Gland / Q000502:physiology; D011956:Receptors, Cell Surface / Q000378:metabolism; D054411:Receptors, Leptin; D012098:Reproduction / Q000502:physiology*; D050796:STAT3 Transcription Factor; D015534:Trans-Activators / Q000502:physiology
D004268:DNA-Binding Proteins; D020738:Leptin; D019869:Phosphatidylinositol 3-Kinases; D011956:Receptors, Cell Surface; D054411:Receptors, Leptin; D050796:STAT3 Transcription Factor; D015534:Trans-Activators; C515448:LEPR protein, human; C494086:STAT3 protein, human