Altered spontaneous brain activity pattern in cognitively normal young adults carrying mutations of APP, presenilin-1/2 and APOE ε4.

OBJECTIVE

To explore genetic effects of amyloid precursor protein (APP), presenilin-1/2 and apolipoprotein E (APOE) ε4 on brain structural and functional alterations in cognitively normal young adults.

MATERIALS AND

METHODS

Eighty healthy adults (mean age 24.0±2.5years; n=18, APP/presenilin-1/2 group; n=31, APOE ε4 group; n=31, control group [without above-mentioned gene mutation]) underwent high-resolution T1-weighted 3D anatomical imaging, resting-state functional MR imaging and neuropsychological assessments. We used voxel-based morphometry and regional homogeneity (ReHo) algorithms to investigate brain structural and functional changes among three groups, and performed correlation analyses between the brain regions with statistically significant difference and neuropsychological results.

RESULTS

No brain structural changes were found, however, ReHo values were increased in right parietal-frontal lobes in APOE ε4 group, and decreased in the left middle temporal gyrus in APP/presenilin-1/2 group compared with controls (all P<0.05). Compared with APOE ε4 group, decreased ReHo values of bilateral temporal lobes were shown in APP/presenilin-1/2 group (P<0.05). ReHo values of right superior frontal gyrus in APOE ε4 group positively correlated with neuropsychological tests scores(P<0.05).

CONCLUSION

Cognitively normal young adults carrying APOE ε4 or APP/presenilin-1/2 had different spontaneous brain activity patterns without cerebral structural differences.