Lipocalin 13 (LCN13)

Lipocalin 13 (LCN13), also known as Odorant-binding protein 2A (OBP2A) in humans, is a member of the lipocalin superfamily of small secreted proteins that typically bind and transport small hydrophobic ligands (1.2.1, 2.3.1). Primarily expressed in the liver, pancreas, and skeletal muscle, LCN13 acts as a hepatokine that plays a critical role in regulating systemic glucose and lipid homeostasis (1.2.1, 2.2.2). It functions as an endogenous insulin sensitizer, enhancing insulin signaling in adipocytes and hepatocytes while suppressing hepatic gluconeogenesis and lipogenesis (1.2.2, 1.2.5). In preclinical models of obesity and type 2 diabetes, LCN13 levels are significantly downregulated, and its restoration via recombinant protein or gene therapy has been shown to ameliorate hyperglycemia and insulin resistance (1.2.1, 2.2.3). Despite its promising role in metabolic regulation, some recent studies have questioned its necessity for systemic metabolic control, highlighting the complexity of its biological role and the need for further investigation into its human physiological relevance (1.1.1, 2.2.3).

Other names

Odorant-binding protein 2AOBP2AOBP2OBPIIaLcn13

Lipocalin 13 acts as an insulin sensitizer by enhancing insulin signaling in adipocytes and hepatocytes. It suppresses hepatic glucose production and lipogenesis while stimulating fatty acid beta-oxidation. Additionally, it triggers glucose-dependent insulin secretion from pancreatic beta-cells (1.2.1, 1.2.2, 1.2.3).