APLN and type 1 diabetes mellitus: Next, the authors explored the mechanism through which Apelin-13 regulates of ER stress and found that it increases the phosphorylation levels of extracellular regulated protein kinases (ERK), protein kinase B (Akt), and AMPK (83), suggesting that Apelin-13 might widely regulate multiple pathways, thereby improving ER stress caused by T1DM.