Syzygium malaccense fruit supplementation protects mice brain against high-fat diet impairment and improves cognitive functions

In this study, we supplemented a high-fat diet (HF) with 5% powder of freeze-dried Syzygium malaccense fruit (HS) and investigated proofs of peripheral insulin resistance, hippocampal AKT-GSK3-beta-tau activation, learning/memory performance, and brain frontal lobe oxidative stress. The intake of HS did not prevent weight gain but promoted peripheral insulin sensitivity, improved AKT signaling in the hippocampus, which prevented the activation of GSK3-beta and lowered tau phosphorylation induced in HF. The results from the Morris water maze cognitive test were consistent with the lower tau-phosphorylation, once the HS group showed lower latency in the acquisition phase and more times crossing the target quadrant when compared with HF. The HS diet improved brain antioxidant enzyme activities. Overall, the intervention with S. malaccense fruit to mice was effective in minimizing cognitive deficit caused by HF consumption and in preventing risk markers associated with Alzheimers disease without reducing weight gain in mice.