Leptin, through its action in the periphery and CNS, produces neuroprotective effects that improve cognitive function and memory. Its dysfunction in signaling pathways and resistance can cause neurodegeneration. Obesity-related inflammation may contribute to leptin resistance. Anti-inflammatory drugs combined with drugs that reduce leptin resistance could be useful for the treatment of AD. The gene discussed is LEP; the disease is obesity due to melanocortin 4 receptor deficiency.