The mechanism study of EGCG on improvement of cognitive function and alleviation of hippocampal insulin resistance in APP/PS 1 transgenetic mice / 中国生化药物杂志

ABSTRACT

Objective To explore mechanism of epigallocatechin-3-gallate (EGCG) on improvement of cognitive function and alleviation of hippocampal insulin resistance in APP/PS 1 transgenetic mice. Method 12 months old female APP/PS 1 mice were randomly divided into 3 groups:model group(Tg), EGCG low dose group (Tg/EGCG-L), high dose group(Tg/EGCG-H). C 57 BL/6 J mice were utilized as control. learning and memory ability in 4 group mice were detected by morris water maze test(MWM). The hippocampal TNF-α/JNK signal and IRS-1 pSer 312 expression were detected by Western blot and immunohistochemical staining. Results Compared with NT mice, Tg mice showed a marked prolongation of the escape latency and swimming distance in the MWM test(P<0.05);Abnormal activation of TNF-α/JNK signaling and increased IRS-1 pSer 312 expression in the hippocampus of Tg mice(P<0.05). EGCG-treated Tg mice showed significantly improvement of all these abnormal changes(P<0.05). Conclusion EGCG treatment is able to alleviate hippocampal insulin resistance and improve cognitive function in the APP/PS 1 mice. which may be partly attributed to the reduction of TNF-α/JNK signaling activity in this AD mouse model.