The mechanism of miR-665 targeting GNB3 in aluminum-induced neuronal apoptosis

Abstract

Background

Aluminum exerts neurotoxic effects through various mechanisms, mainly manifested as impaired learning and memory function.

Methods

Forty SD rats were divided into 0, 10, 20, and 40 mM maltol aluminum [Al(mal)₃] groups. Cell experiments are divided into 0, 100, 200, and 400 μM Al(mal)₃ dose group and control, Al(mal)₃, Al(mal)₃+inhibitor NC, Al(mal)₃+miR-665 inhibitor intervention group. Water maze was used to detect the learning and memory function of rats, HE staining was used to observe the morphology and number of neurons in the CA1 area of the rat hippocampus, Flow cytometry was used to detect the apoptosis of PC12 cells, PCR and Western blotting were used to detect the expression of Caspase3, miR-665 and GNB3/PI3K/AKT proteins. The target binding relationship between miR-665 and GNB3 was verified by double luciferase reporter gene experiment.

Results

In vivo experimental results showed that with the increase of Al(mal)₃ concentration, the escape latency of rats was prolonged, the target quadrant dwell time was shortened, and the number of crossing platform was reduced. Moreover, the arrangement of neurons was loose and the number decreased; the expression of Caspase3 and miR-665 increased, while the expression of GNB3/PI3K/AKT proteins decreased. In vitro experiments, with the increase of Al(mal)₃ concentration, apoptosis rate of PC12 cells increased, the expression of Caspase3, miR-665 and GNB3/PI3K/AKT proteins were consistent with rat results. After inhibiting miR-665 in the intervention group experiment, apoptosis rate of PC12 cells in the aluminum exposure group decreased, the expression of Caspase3 and miR-665 decreased, and the expression of GNB3/PI3K/AKT proteins increased.

Conclusion

MiR-665 plays an important role in aluminum induced neuronal apoptosis by targeting GNB3 and regulating the PI3K/AKT pathway.