Nutrients, Vol. 17, Pages 2679: Avenanthramide-C Mitigates High-Fat Diet-Accelerated Alzheimer’s Pathologies via NOD1-Driven Neuroinflammation in 5×FAD Mice
Nutrients doi: 10.3390/nu17162679
Authors:
Ming Wang
Baoyuan Jin
Jia Xu
Chuang Wang
Background: Obesity is clinically known to be associated with an increased risk and aggravated pathology of Alzheimer’s disease (AD). A high-fat diet (HFD), the major contributor to obesity, induces neuroinflammation and central insulin resistance, both of which are linked to synaptic dysfunction. Our previous studies demonstrated that avenanthramide-C (Avn-C), a natural oat-derived phenolic compound, exerts anti-inflammatory effects and alleviates synaptic dysfunction in conventional AD models. The present study aimed to elucidate the underlying mechanisms of Avn-C in obesity-accelerated AD. Methods: Two-month-old male 5×FAD mice were fed an HFD to induce obesity and then treated with Avn-C. Cognitive performance, synaptic function, and structure were assessed via behavioral tests, electrophysiological recordings, and Golgi–Cox staining, respectively. Cytokine levels were quantified using ELISA and Western blotting. To explore the underlying mechanism, the NOD1 agonist C12-iE-DAP was administered to evaluate its effect on Avn-C-mediated neuroprotection. Results: Avn-C reduced Aβ deposition, enhanced the expression of synapse proteins, and restored synaptic plasticity, thereby improving both spatial and recognition memory in obese 5×FAD mice. Furthermore, Avn-C reduced neuroinflammation by inhibiting the NOD1/RIP2/NF-κB signaling pathway. Co-treatment with C12-iE-DAP abolished the beneficial effects of Avn-C on neuroinflammation, Aβ pathology, and cognitive function. Conclusions: These results suggest that Avn-C mitigates obesity-exacerbated AD-like pathological features by suppressing NOD1/RIP2/NF-κB-mediated neuroinflammation and could be a new potential therapeutic strategy for obesity-associated AD.
Background: Obesity is clinically known to be associated with an increased risk and aggravated pathology of Alzheimer’s disease (AD). A high-fat diet (HFD), the major contributor to obesity, induces neuroinflammation and central insulin resistance, both of which are linked to synaptic dysfunction. Our previous studies demonstrated that avenanthramide-C (Avn-C), a natural oat-derived phenolic compound, exerts anti-inflammatory effects and alleviates synaptic dysfunction in conventional AD models. The present study aimed to elucidate the underlying mechanisms of Avn-C in obesity-accelerated AD. Methods: Two-month-old male 5×FAD mice were fed an HFD to induce obesity and then treated with Avn-C. Cognitive performance, synaptic function, and structure were assessed via behavioral tests, electrophysiological recordings, and Golgi–Cox staining, respectively. Cytokine levels were quantified using ELISA and Western blotting. To explore the underlying mechanism, the NOD1 agonist C12-iE-DAP was administered to evaluate its effect on Avn-C-mediated neuroprotection. Results: Avn-C reduced Aβ deposition, enhanced the expression of synapse proteins, and restored synaptic plasticity, thereby improving both spatial and recognition memory in obese 5×FAD mice. Furthermore, Avn-C reduced neuroinflammation by inhibiting the NOD1/RIP2/NF-κB signaling pathway. Co-treatment with C12-iE-DAP abolished the beneficial effects of Avn-C on neuroinflammation, Aβ pathology, and cognitive function. Conclusions: These results suggest that Avn-C mitigates obesity-exacerbated AD-like pathological features by suppressing NOD1/RIP2/NF-κB-mediated neuroinflammation and could be a new potential therapeutic strategy for obesity-associated AD. Read More