Perilipin

Perilipin is a protein that coats lipid droplets in adipocytes, the fat storing cells in adipose tissue. Perilipin acts as a protective coating from the body’s natural lipases, such as hormone-sensitive lipase, that break triglycerides into glycerol and free fatty acids for use in metabolism, a process called lipolysis.

Perilipin is hyperphosphorylated by PKA following β-adrenergic receptor activation. Phosphorylated perilipin changes conformation, exposing the stored lipids to hormone-sensitive lipase-mediated lipolysis.

Perilipin is an important regulator of lipid storage. Perilipin expression is elevated in obese animals and humans. Perilipin-null mice eat more food than wild-type mice, but gain 1/3 less fat than wild-type mice on the same diet; Perilipin-null mice are thinner, with more lean muscle mass. Perilipin-null mice also exhibit enhanced leptin production and a greater tendency to develop insulin resistance than wild-type mice. Polymorphisms in the human perilipin (PLIN) gene, 13041A>G and 14995A>T, have been associated with increased risk of obesity in women. The PLIN polymorphism 11482G>A has been associated with decreased perilipin expression and increased lipolysis in women.