Therefore, the possible negative effects induced by proinflammatory molecules (leptin, tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), transforming growth factor β1 (TGF-β1), C-reactive protein, adiponectin and resistin) on AHR and in general on asthma [23,24], may be delayed in time, as they need a latency period before showing their effects. This evidence concerns the gene TGFB1 and asthma.