Exploration of Neuroprotective Therapy

Table 3. Strain-efficacy mapping of probiotics in Alzheimer’s disease and mild cognitive impairment.

Study (author, year)	Strain(s) used	Dose (CFU)	Route & Duration	Cognitive outcomes	Biomarker outcomes
Akbari et al. [3], 2016	L. acidophilus, L. casei, B. bifidum, L. fermentum	2 × 10⁹ each/day	Oral, 12 weeks	MMSE ↑ 27.9% vs. ↓ 5.03% in controls	hs-CRP ↓, MDA ↓
Akhgarjand et al. [40], 2022	L. rhamnosus HA-114 or B. longum R0175	10¹⁵/day	Oral, 12 weeks	MMSE ↑ by 4.86 points, IADLs improved	No change in basic ADLs
Hsu et al. [41], 2024	Multi-strain Lactobacillus + Bifidobacterium	5 × 10⁷–1 × 10¹⁰/day	Oral, 12 weeks	Slowed cognitive decline	IL-1β ↓, SOD ↑, BDNF ↑
Kobayashi et al. [44], 2017	Bifidobacterium breve A1	2 × 10¹⁰/day	Oral, 12 weeks	Cognitive impairment reduced	Not specified
Agahi et al. [45], 2018	Mixed Lactobacillus + Bifidobacterium strains	Not specified	Oral, 12 weeks	Mild cognitive improvement (stage-dependent)	Not specified

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CFU: colony-forming units; MMSE: mini-mental state examination; hs-CRP: high-sensitivity C-reactive protein; MDA: malondialdehyde; IADLs: instrumental activities of daily living; IL-1β: interleukin-1 beta; SOD: superoxide dismutase; BDNF: brain-derived neurotrophic factor.

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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.

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The authors declare that they have no conflicts of interest.

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