Leptin has been shown to induce or to potentiate together with interferon γ (IFNγ), with tumor necrosis factor α (TNFα) or with IFNγ and IL-1β, NO production in murine J774A.1 macrophages, rat adipocytes, C6 glioma cell-line, and rat vascular smooth muscle cells (VSMCs) [39–42]. This evidence concerns the gene IL1B and glioma.