This Human Leptin (LEP) ELISA Kit is suitable for qualitatively determining LEP concentrations in multiple biological fluids, including human serum, plasma, and tissue homogenates in vitro. Leptin is an adipocyte-secreted peptide, and its synthesis is based on fat stores proportion. Once produced, leptin reaches the brain by the bloodstream and vagal nerve, and enter it by transcytosis across the blood-brain barrier (BBB), through the mechanism of saturating transport. Leptin binding to leptin receptor isoform b (LepRb) recruits and activates JAK2, allowing the activation of Y1138-STAT3, Y1138-STAT4, Y985-ERK, Y1077-STAT2, and IRS-1-PI3K pathways that finally leads to anorexic effects and energy homeostasis. Additionally, leptin can also improve learning and memory, affect hippocampal synaptic plasticity, exert neuroprotective efficacy, and reduce the risk of several neuropsychiatric diseases. This kit uses the quantitative sandwich-based enzyme immunoassay technique to measure the amo...