OBJECTIVETo observe the effect of intracerebroventricular injection of rAAV-HIF-1α on hippocampal neuronal apoptosis in a rat model of Alzheimer disease (AD).

METHODSThirty-two male SD rats (250-300 g) were randomized into 4 groups (n=8), including the normal control group without any treatment, AD model group with right intracerebroventricular injection of 2 µl Aβ25-35 (10 mg/m1), sham-operated group with right intracerebroventricular injection of 2 µl normal saline, and AD+ rAAV-HIF-1α group with right intracerebroventricular injection of 10 µl rAAV-HIF-1a (1×10¹² v.g./m1) one week after Aβ25-35 injection. The rats were sacrificed to detect the expression of HIF-1α and apoptosis of hippocampal neurons 5 weeks after Aβ25-35 or saline injection.

RESULTSWestern blotting showed that the expression of HIF-1α was significantly higher in AD+rAAV-HIF-1α group (451.59±34.39) than in normal control group (229.05±41.28) and sham-operated group (216.29±37.08) (P<0.05) without significant difference between the latter two groups. The apoptotic ratio of the hippocampal neurons was significantly higher in AD model group ([19.49±2.59]%) than in normal control group ([5.41±0.75]%) and sham-operated group ([5.28±0.66]%) in (P<0.05), and intracerebroventricular injection of rAAV-HIF-1α resulted in a significant reduction of the apoptotic ratio in the AD rats ([12.07±2.06]%) (P<0.05).

CONCLUSIONIntracerebroventricular injection of rAAV-HIF-1α can inhibit hippocampal neuronal apoptosis in the rat model of AD.