LEP and psoriasis: Indeed, several meta-analyses have evaluated the circulating concentrations of important adipokines and found that the leptin concentrations are significantly higher in non-obese patients with psoriasis [53, 54], either under the fasting or the postprandial status [55, 56], indicating that the increase leptin levels in psoriatic patients might not only originate from adipocytes but also from keratinocytes and endothelial cells [57].