To elucidate the possible mechanisms of CVE against HFD-induced memory impairments and decreases in neurogenesis, BDNF levels were measured in hippocampal homogenates because HFD-induced obesity decreased BDNF levels, which play important roles in memory formation [44] and adult neurogenesis [45]. The gene discussed is BDNF; the disease is obesity due to melanocortin 4 receptor deficiency.