IGF-1 Stereotaxic Injection Induces BDNF Expression After Bilateral Common Carotid Artery Occlusion

Insulin-like growth factor-1 (IGF-1) is a neuroprotective growth factor widely expressed in the brain. Prior studies have shown that IGF-1 and phosphorylated protein kinase B (pAKT) are downregulated in the hippocampus of a bilateral common carotid artery (BCCAO) model. However, the relationship between AKT, ERK, and BDNF expression in this BCCAO model remains unclear. In particular, the effects of IGF-1 on pAKT and phosphorylated extracellular signal-related protein kinase (pERK) in the BCCAO model are not understood. In the present study, we investigated the effect of IGF-1 stereotaxic injection on pAKT and pERK in a BCCAO model.

To create the BCCAO model, the carotid arteries of rats were exposed and occluded. Three hours post-occlusion, IGF-1 was injected into BCCAO rats using a stereotaxic injector. Western blotting was conducted on the cerebral cortex and hippocampal tissues collected three days after BCCAO.

Three days after BCCAO model induction, BDNF expression was increased in the cortex and hippocampus. There was a significant difference in cortex and hippocampal pAKT/AKT and pERK/ERK expression between the BCCAO and IGF-1-treated group.

Stereotaxic injection of IGF-1 in rats with BCCAO enhances BDNF expression in the cortex and hippocampus 3 days post-surgery. Further, this treatment simultaneously increased pAKT and pERK levels in both regions.