Apelin-13 is a 13-amino acid peptide sequence found in the central and peripheral nervous system that is an endogenous ligand for the G protein-coupled receptor angiotensin II protein J (APJ), with an EC50 value of 0.37 nM for APJ.Apelin-13 has vasodilatory and antihypertensive activity and can be used to study type 2 diabetic syndrome. Apelin-13 has vasodilatory and antihypertensive activities and can be used to study type 2 diabetes syndrome.

APJ:0.37 nM

在培养的PC12细胞中，观察到相同的保护效果。用其siRNA沉默Nrf2基因，取消了Apelin 13防止I/R引起的PC12细胞损伤、氧化应激和炎症的作用。AMPK的siRNA抑制削减了Apelin 13诱导的Nrf2表达水平，并减弱了Apelin 13的保护效果。GSK-3β与Nrf2之间的相互作用关系也通过相对过表达得到验证。通过使用选择性抑制剂，我们进一步确认了AMPK/GSK-3β/Nrf2上游是AR/Gα/PLC/IP3/CaMKK。

通过每日腹腔注射200 µg/kg的剂量连续使用4周，Apelin-13能显著改善心脏功能、胰岛素抗性以及脂质代谢。它能显著降低血清中TNF-α与瘦素的水平，并诱导在血清中Apelin-12的表达，同时明显提高GLUT4和p-AMPKα2[2]的水平。当通过单次剂量10和100 μM的脑室内注射给药时，Apelin-13能增加大部分苍白球神经元的自发放电[3]。

For in vitro study, PC12 cells were used,proteases inhibitors or siRNA were used.?Protein levels were investigated by western blotting.

In vivo, the I/R model was induced and Apelin 13 was given intracerebroventricularly 15 min before reperfusion.?The neurobehavioral scores, infarction volumes, and some cytokines in the brain were measured.