Neuroavailable peptides from hempseed protein hydrolysates reduce hippocampal inflammation and glial activation in a scopolamine-induced Alzheimer’s disease

Abstract

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by cognitive impairment, synaptic dysfunction, and neuronal loss. Neuroinflammation, driven by the activation of microglia and astrocytes, is a key contributor to AD pathology, amplifying oxidative stress and amyloid-β toxicity. Modulation of neuroinflammatory pathways thus represents a promising therapeutic strategy. In this study, we evaluated the effects of a food-grade hempseed protein hydrolysate (HPH20A) on hippocampal inflammation and glial activation in a scopolamine-induced mouse model of AD. Mice were orally supplemented with HPH20A (10 mg/kg/day) for 12 weeks. Hippocampal tissue was analyzed by RT-qPCR and immunohistochemistry to assess the expression of glial and inflammatory markers. To identify peptides capable of reaching the brain, we employed a double transwell in vitro system simulating intestinal and blood–brain barrier (BBB) transport, followed by LC-TIMS-MS/MS peptidomics, in silico bioactivity prediction, and molecular docking. HPH20A supplementation significantly attenuated the expression of pro-inflammatory markers, including GFAP, IBA1, TREM2, CD68, iNOS, COX2, and IL-6, and increased the anti-inflammatory cytokine IL-10. Peptidomic analysis identified two peptides, NVDTELAHKL and DSETVKRL, consistently present across intestinal, systemic, and brain compartments. These peptides were predicted to exhibit anti-inflammatory activity and demonstrated high-affinity binding to AD-related targets (APP, TREM2, and AChE) in docking simulations. Taken together, these findings suggest that HPH20A exerts neuroprotective effects by modulating hippocampal inflammation inflammation, potentially through specific bioactive peptides capable of crossing the BBB. Our results support the potential of hempseed-derived peptides as dietary modulators of neuroinflammation in early stages of neurodegenerative disease.