Exploration of Neuroprotective Therapy

Table 1. Evidence framework for probiotic interventions in Alzheimer’s disease and mild cognitive impairment.

Study (author, year)	Study type	Sample size	Follow-up	Cognitive outcome	Biomarker outcome	Strength of causality
Akbari et al. [3], 2016	RCT	60	12 weeks	↑ MMSE	↓ IL-6	Moderate
Hsu et al. [41], 2024	RCT	80	8 weeks	↑ MoCA	↑ BDNF	Moderate
Akhgarjand et al. [40], 2022	RCT	70	12 weeks	↑ MMSE	↓ TNF-α	Moderate
Guo et al. [1], 2021	Systematic review	N/A	N/A	N/A	N/A	Low
Leblhuber et al. [2], 2018	Cohort	50	24 weeks	Association only	N/A	Low
Tripathi et al. [8], 2024	Meta-analysis	400	Varies	↑ Cognitive domains	↑ BDNF/↓ IL-6	Moderate

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RCT: randomized controlled trial; MMSE: mini-mental state examination; IL-6: interleukin-6; MoCA: Montreal Cognitive Assessment; BDNF: brain-derived neurotrophic factor; TNF-α: tumor necrosis factor-alpha.

Declarations

Author contributions

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.

Conflicts of interest

The authors declare that they have no conflicts of interest.

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Not applicable.

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