IRS1 and early-onset autosomal dominant Alzheimer disease: Because other authors suggested an involvement of the tumor necrosis factor α (TNF-α)/c-Jun n-terminal kinase (JNK) pathway in Alzheimer’s disease triggered by Aβ-oligomers29, we measured TNF-α, pSAP-JNK, and phosphorylated insulin receptor substrate 1 (p-IRS Ser636) as well as synaptophysin and PSD-95 as synaptic markers in hippocampal brain tissue from the groups fed the high-GI diet (Fig. 5).