Exploration of Neuroprotective Therapy

Table 5. Potential mechanisms of action of probiotics in Alzheimer’s disease.

Mechanism	Key actions
Reduced neuroinflammation and oxidative stress	↓ Pro-inflammatory cytokines (TNF-α, IL-1, IL-6), ↓ ROS, ↑ SOD, ↓ NF-κB activation
Gut-brain axis modulation	↑ Gut barrier integrity, ↓ LPS translocation, ↓ intestinal inflammation
Boosting neuroactive metabolites	↑ SCFAs (butyrate, propionate), ↓ Aβ deposition, ↑ cognitive performance
Synergistic multifactorial effects	Modulates neuroendocrine, neuroimmune, neurometabolic pathways→↑ memory

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TNF-α: tumor necrosis factor-alpha; IL-1: interleukin-1; ROS: reactive oxygen species; SOD: superoxide dismutase; NF-κB: nuclear factor kappa-light-chain-enhancer of activated B cells; LPS: lipopolysaccharides; SCFAs: short-chain fatty acids; Aβ: amyloid-beta.

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AAS: Conceptualization, Investigation, Data curation, Writing—original draft. HSW: Conceptualization, Supervision, Writing—review & editing, Methodology. AP: Investigation, Writing—original draft, Writing—review & editing. ST: Data curation, Writing—review & editing. BS: Data curation, Writing—review & editing. NN: Investigation, Writing—review & editing. All authors read and approved the submitted version.

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The authors declare that they have no conflicts of interest.

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