Apelin production is also altered in obesity, with changes in serumapelin detected in multiple tissues in obese patients compared to non-obese controls.66 These results suggest that apelin might play an important role in obesityas apelin inhibits lipolysis in adipocytes68 and is involved in angiogenesis in adipose tissue.69 Here, APLN is linked to obesity due to melanocortin 4 receptor deficiency.