The adipocytokine apelin is a peptide, Apelin and its receptor are abundantly 
expressed in the nervous and cardiovascular systems. Previous studies had found 
apelin-13 reduces brain injuries and postischemic cerebral edema through 
blocking programmed cell death, Apelin-13 is also able to inhibit glucose 
deprivation induced cardiomyocyte autophagy in a concentration dependent 
fashion. To observe the effect of Apelin-13 on the brain injury induced by 
traumatic brain injury (TBI), and explore the effect of Apelin-13 on autophagy 
in TBI, We performed The neurological test, and the numbers of TBI-induced 
neural cell death were also counted by propidium iodide labeling. At last, the 
autophagy associated proteins LC3, Beclin-1, Bcl-2, p62 were also assessed with 
western-blotting. Compared with saline vehicle groups, the neural cell death, 
lesion volume, and neural dysfunction were attenuated by apelin-13 after TBI. In 
additionally, Apelin-13 also reversed TBI induced downregulation of LC3, 
Beclin-1, Bcl-2, p62 expression, compared with saline vehicle groups, at 24 and 
48 h post TBI. Apelin-13 attenuates TBI induced brain damage by suppressing 
autophagy. All these results revealed that Apelin-13 suppressed autophagy. The 
autophagy may be involved in the mechanism of Apelin-13 rescue the subsequent 
damaged neuron in TBI.